Update contrib/restricted/abseil-cpp to 20240116.0

158 files changed, 6712 insertions, 5227 deletions

diff --git a/contrib/restricted/abseil-cpp/absl/algorithm/algorithm.h b/contrib/restricted/abseil-cpp/absl/algorithm/algorithm.h
index e9b4733872..59aeed7d26 100644
--- a/contrib/restricted/abseil-cpp/absl/algorithm/algorithm.h
+++ b/contrib/restricted/abseil-cpp/absl/algorithm/algorithm.h
@@ -31,92 +31,17 @@
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
-namespace algorithm_internal {
-
-// Performs comparisons with operator==, similar to C++14's `std::equal_to<>`.
-struct EqualTo {
-  template <typename T, typename U>
-  bool operator()(const T& a, const U& b) const {
-    return a == b;
-  }
-};
-
-template <typename InputIter1, typename InputIter2, typename Pred>
-bool EqualImpl(InputIter1 first1, InputIter1 last1, InputIter2 first2,
-               InputIter2 last2, Pred pred, std::input_iterator_tag,
-               std::input_iterator_tag) {
-  while (true) {
-    if (first1 == last1) return first2 == last2;
-    if (first2 == last2) return false;
-    if (!pred(*first1, *first2)) return false;
-    ++first1;
-    ++first2;
-  }
-}
-
-template <typename InputIter1, typename InputIter2, typename Pred>
-bool EqualImpl(InputIter1 first1, InputIter1 last1, InputIter2 first2,
-               InputIter2 last2, Pred&& pred, std::random_access_iterator_tag,
-               std::random_access_iterator_tag) {
-  return (last1 - first1 == last2 - first2) &&
-         std::equal(first1, last1, first2, std::forward<Pred>(pred));
-}
-
-// When we are using our own internal predicate that just applies operator==, we
-// forward to the non-predicate form of std::equal. This enables an optimization
-// in libstdc++ that can result in std::memcmp being used for integer types.
-template <typename InputIter1, typename InputIter2>
-bool EqualImpl(InputIter1 first1, InputIter1 last1, InputIter2 first2,
-               InputIter2 last2, algorithm_internal::EqualTo /* unused */,
-               std::random_access_iterator_tag,
-               std::random_access_iterator_tag) {
-  return (last1 - first1 == last2 - first2) &&
-         std::equal(first1, last1, first2);
-}
-
-template <typename It>
-It RotateImpl(It first, It middle, It last, std::true_type) {
-  return std::rotate(first, middle, last);
-}
-
-template <typename It>
-It RotateImpl(It first, It middle, It last, std::false_type) {
-  std::rotate(first, middle, last);
-  return std::next(first, std::distance(middle, last));
-}
-
-}  // namespace algorithm_internal
-
 // equal()
+// rotate()
 //
-// Compares the equality of two ranges specified by pairs of iterators, using
-// the given predicate, returning true iff for each corresponding iterator i1
-// and i2 in the first and second range respectively, pred(*i1, *i2) == true
-//
-// This comparison takes at most min(`last1` - `first1`, `last2` - `first2`)
-// invocations of the predicate. Additionally, if InputIter1 and InputIter2 are
-// both random-access iterators, and `last1` - `first1` != `last2` - `first2`,
-// then the predicate is never invoked and the function returns false.
+// Historical note: Abseil once provided implementations of these algorithms
+// prior to their adoption in C++14. New code should prefer to use the std
+// variants.
 //
-// This is a C++11-compatible implementation of C++14 `std::equal`.  See
-// https://en.cppreference.com/w/cpp/algorithm/equal for more information.
-template <typename InputIter1, typename InputIter2, typename Pred>
-bool equal(InputIter1 first1, InputIter1 last1, InputIter2 first2,
-           InputIter2 last2, Pred&& pred) {
-  return algorithm_internal::EqualImpl(
-      first1, last1, first2, last2, std::forward<Pred>(pred),
-      typename std::iterator_traits<InputIter1>::iterator_category{},
-      typename std::iterator_traits<InputIter2>::iterator_category{});
-}
-
-// Overload of equal() that performs comparison of two ranges specified by pairs
-// of iterators using operator==.
-template <typename InputIter1, typename InputIter2>
-bool equal(InputIter1 first1, InputIter1 last1, InputIter2 first2,
-           InputIter2 last2) {
-  return absl::equal(first1, last1, first2, last2,
-                     algorithm_internal::EqualTo{});
-}
+// See the documentation for the STL <algorithm> header for more information:
+// https://en.cppreference.com/w/cpp/header/algorithm
+using std::equal;
+using std::rotate;
 
 // linear_search()
 //
@@ -133,26 +58,6 @@ bool linear_search(InputIterator first, InputIterator last,
   return std::find(first, last, value) != last;
 }
 
-// rotate()
-//
-// Performs a left rotation on a range of elements (`first`, `last`) such that
-// `middle` is now the first element. `rotate()` returns an iterator pointing to
-// the first element before rotation. This function is exactly the same as
-// `std::rotate`, but fixes a bug in gcc
-// <= 4.9 where `std::rotate` returns `void` instead of an iterator.
-//
-// The complexity of this algorithm is the same as that of `std::rotate`, but if
-// `ForwardIterator` is not a random-access iterator, then `absl::rotate`
-// performs an additional pass over the range to construct the return value.
-template <typename ForwardIterator>
-ForwardIterator rotate(ForwardIterator first, ForwardIterator middle,
-                       ForwardIterator last) {
-  return algorithm_internal::RotateImpl(
-      first, middle, last,
-      std::is_same<decltype(std::rotate(first, middle, last)),
-                   ForwardIterator>());
-}
-
 ABSL_NAMESPACE_END
 }  // namespace absl
 
diff --git a/contrib/restricted/abseil-cpp/absl/algorithm/container.h b/contrib/restricted/abseil-cpp/absl/algorithm/container.h
index 679e02676c..c7bafae147 100644
--- a/contrib/restricted/abseil-cpp/absl/algorithm/container.h
+++ b/contrib/restricted/abseil-cpp/absl/algorithm/container.h
@@ -52,6 +52,7 @@
 
 #include "absl/algorithm/algorithm.h"
 #include "absl/base/macros.h"
+#include "absl/base/nullability.h"
 #include "absl/meta/type_traits.h"
 
 namespace absl {
@@ -116,18 +117,6 @@ template <class Key, class Hash, class KeyEqual, class Allocator>
 struct IsUnorderedContainer<std::unordered_set<Key, Hash, KeyEqual, Allocator>>
     : std::true_type {};
 
-// container_algorithm_internal::c_size. It is meant for internal use only.
-
-template <class C>
-auto c_size(C& c) -> decltype(c.size()) {
-  return c.size();
-}
-
-template <class T, std::size_t N>
-constexpr std::size_t c_size(T (&)[N]) {
-  return N;
-}
-
 }  // namespace container_algorithm_internal
 
 // PUBLIC API
@@ -348,20 +337,10 @@ container_algorithm_internal::ContainerDifferenceType<const C> c_count_if(
 template <typename C1, typename C2>
 container_algorithm_internal::ContainerIterPairType<C1, C2> c_mismatch(C1& c1,
                                                                        C2& c2) {
-  auto first1 = container_algorithm_internal::c_begin(c1);
-  auto last1 = container_algorithm_internal::c_end(c1);
-  auto first2 = container_algorithm_internal::c_begin(c2);
-  auto last2 = container_algorithm_internal::c_end(c2);
-
-  for (; first1 != last1 && first2 != last2; ++first1, (void)++first2) {
-    // Negates equality because Cpp17EqualityComparable doesn't require clients
-    // to overload both `operator==` and `operator!=`.
-    if (!(*first1 == *first2)) {
-      break;
-    }
-  }
-
-  return std::make_pair(first1, first2);
+  return std::mismatch(container_algorithm_internal::c_begin(c1),
+                       container_algorithm_internal::c_end(c1),
+                       container_algorithm_internal::c_begin(c2),
+                       container_algorithm_internal::c_end(c2));
 }
 
 // Overload of c_mismatch() for using a predicate evaluation other than `==` as
@@ -370,56 +349,33 @@ container_algorithm_internal::ContainerIterPairType<C1, C2> c_mismatch(C1& c1,
 template <typename C1, typename C2, typename BinaryPredicate>
 container_algorithm_internal::ContainerIterPairType<C1, C2> c_mismatch(
     C1& c1, C2& c2, BinaryPredicate pred) {
-  auto first1 = container_algorithm_internal::c_begin(c1);
-  auto last1 = container_algorithm_internal::c_end(c1);
-  auto first2 = container_algorithm_internal::c_begin(c2);
-  auto last2 = container_algorithm_internal::c_end(c2);
-
-  for (; first1 != last1 && first2 != last2; ++first1, (void)++first2) {
-    if (!pred(*first1, *first2)) {
-      break;
-    }
-  }
-
-  return std::make_pair(first1, first2);
+  return std::mismatch(container_algorithm_internal::c_begin(c1),
+                       container_algorithm_internal::c_end(c1),
+                       container_algorithm_internal::c_begin(c2),
+                       container_algorithm_internal::c_end(c2), pred);
 }
 
 // c_equal()
 //
 // Container-based version of the <algorithm> `std::equal()` function to
 // test whether two containers are equal.
-//
-// NOTE: the semantics of c_equal() are slightly different than those of
-// equal(): while the latter iterates over the second container only up to the
-// size of the first container, c_equal() also checks whether the container
-// sizes are equal.  This better matches expectations about c_equal() based on
-// its signature.
-//
-// Example:
-//   vector v1 = <1, 2, 3>;
-//   vector v2 = <1, 2, 3, 4>;
-//   equal(std::begin(v1), std::end(v1), std::begin(v2)) returns true
-//   c_equal(v1, v2) returns false
-
 template <typename C1, typename C2>
 bool c_equal(const C1& c1, const C2& c2) {
-  return ((container_algorithm_internal::c_size(c1) ==
-           container_algorithm_internal::c_size(c2)) &&
-          std::equal(container_algorithm_internal::c_begin(c1),
-                     container_algorithm_internal::c_end(c1),
-                     container_algorithm_internal::c_begin(c2)));
+  return std::equal(container_algorithm_internal::c_begin(c1),
+                    container_algorithm_internal::c_end(c1),
+                    container_algorithm_internal::c_begin(c2),
+                    container_algorithm_internal::c_end(c2));
 }
 
 // Overload of c_equal() for using a predicate evaluation other than `==` as
 // the function's test condition.
 template <typename C1, typename C2, typename BinaryPredicate>
 bool c_equal(const C1& c1, const C2& c2, BinaryPredicate&& pred) {
-  return ((container_algorithm_internal::c_size(c1) ==
-           container_algorithm_internal::c_size(c2)) &&
-          std::equal(container_algorithm_internal::c_begin(c1),
-                     container_algorithm_internal::c_end(c1),
-                     container_algorithm_internal::c_begin(c2),
-                     std::forward<BinaryPredicate>(pred)));
+  return std::equal(container_algorithm_internal::c_begin(c1),
+                    container_algorithm_internal::c_end(c1),
+                    container_algorithm_internal::c_begin(c2),
+                    container_algorithm_internal::c_end(c2),
+                    std::forward<BinaryPredicate>(pred));
 }
 
 // c_is_permutation()
@@ -428,20 +384,20 @@ bool c_equal(const C1& c1, const C2& c2, BinaryPredicate&& pred) {
 // to test whether a container is a permutation of another.
 template <typename C1, typename C2>
 bool c_is_permutation(const C1& c1, const C2& c2) {
-  using std::begin;
-  using std::end;
-  return c1.size() == c2.size() &&
-         std::is_permutation(begin(c1), end(c1), begin(c2));
+  return std::is_permutation(container_algorithm_internal::c_begin(c1),
+                             container_algorithm_internal::c_end(c1),
+                             container_algorithm_internal::c_begin(c2),
+                             container_algorithm_internal::c_end(c2));
 }
 
 // Overload of c_is_permutation() for using a predicate evaluation other than
 // `==` as the function's test condition.
 template <typename C1, typename C2, typename BinaryPredicate>
 bool c_is_permutation(const C1& c1, const C2& c2, BinaryPredicate&& pred) {
-  using std::begin;
-  using std::end;
-  return c1.size() == c2.size() &&
-         std::is_permutation(begin(c1), end(c1), begin(c2),
+  return std::is_permutation(container_algorithm_internal::c_begin(c1),
+                             container_algorithm_internal::c_end(c1),
+                             container_algorithm_internal::c_begin(c2),
+                             container_algorithm_internal::c_end(c2),
                              std::forward<BinaryPredicate>(pred));
 }
 
@@ -818,6 +774,36 @@ void c_shuffle(RandomAccessContainer& c, UniformRandomBitGenerator&& gen) {
                std::forward<UniformRandomBitGenerator>(gen));
 }
 
+// c_sample()
+//
+// Container-based version of the <algorithm> `std::sample()` function to
+// randomly sample elements from the container without replacement using a
+// `gen()` uniform random number generator and write them to an iterator range.
+template <typename C, typename OutputIterator, typename Distance,
+          typename UniformRandomBitGenerator>
+OutputIterator c_sample(const C& c, OutputIterator result, Distance n,
+                        UniformRandomBitGenerator&& gen) {
+#if defined(__cpp_lib_sample) && __cpp_lib_sample >= 201603L
+  return std::sample(container_algorithm_internal::c_begin(c),
+                     container_algorithm_internal::c_end(c), result, n,
+                     std::forward<UniformRandomBitGenerator>(gen));
+#else
+  // Fall back to a stable selection-sampling implementation.
+  auto first = container_algorithm_internal::c_begin(c);
+  Distance unsampled_elements = c_distance(c);
+  n = (std::min)(n, unsampled_elements);
+  for (; n != 0; ++first) {
+    Distance r =
+        std::uniform_int_distribution<Distance>(0, --unsampled_elements)(gen);
+    if (r < n) {
+      *result++ = *first;
+      --n;
+    }
+  }
+  return result;
+#endif
+}
+
 //------------------------------------------------------------------------------
 // <algorithm> Partition functions
 //------------------------------------------------------------------------------
@@ -1657,7 +1643,7 @@ bool c_prev_permutation(C& c, LessThan&& comp) {
 //
 // Container-based version of the <numeric> `std::iota()` function
 // to compute successive values of `value`, as if incremented with `++value`
-// after each element is written. and write them to the container.
+// after each element is written, and write them to the container.
 template <typename Sequence, typename T>
 void c_iota(Sequence& sequence, const T& value) {
   std::iota(container_algorithm_internal::c_begin(sequence),
diff --git a/contrib/restricted/abseil-cpp/absl/algorithm/ya.make b/contrib/restricted/abseil-cpp/absl/algorithm/ya.make
index 3b66e3e400..3f9af85fe6 100644
--- a/contrib/restricted/abseil-cpp/absl/algorithm/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/algorithm/ya.make
@@ -6,9 +6,9 @@ LICENSE(Apache-2.0)
 
 LICENSE_TEXTS(.yandex_meta/licenses.list.txt)
 
-VERSION(20230802.1)
+VERSION(20240116.0)
 
-ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20230802.1.tar.gz)
+ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20240116.0.tar.gz)
 
 NO_RUNTIME()
 
diff --git a/contrib/restricted/abseil-cpp/absl/base/attributes.h b/contrib/restricted/abseil-cpp/absl/base/attributes.h
index a7f279a025..d4f67a1295 100644
--- a/contrib/restricted/abseil-cpp/absl/base/attributes.h
+++ b/contrib/restricted/abseil-cpp/absl/base/attributes.h
@@ -687,7 +687,7 @@
 
 // When deprecating Abseil code, it is sometimes necessary to turn off the
 // warning within Abseil, until the deprecated code is actually removed. The
-// deprecated code can be surrounded with these directives to acheive that
+// deprecated code can be surrounded with these directives to achieve that
 // result.
 //
 // class ABSL_DEPRECATED("Use Bar instead") Foo;
@@ -747,9 +747,52 @@
 #define ABSL_CONST_INIT
 #endif
 
-// These annotations are not available yet due to fear of breaking code.
-#define ABSL_ATTRIBUTE_PURE_FUNCTION
-#define ABSL_ATTRIBUTE_CONST_FUNCTION
+// ABSL_ATTRIBUTE_PURE_FUNCTION
+//
+// ABSL_ATTRIBUTE_PURE_FUNCTION is used to annotate declarations of "pure"
+// functions. A function is pure if its return value is only a function of its
+// arguments. The pure attribute prohibits a function from modifying the state
+// of the program that is observable by means other than inspecting the
+// function's return value. Declaring such functions with the pure attribute
+// allows the compiler to avoid emitting some calls in repeated invocations of
+// the function with the same argument values.
+//
+// Example:
+//
+//  ABSL_ATTRIBUTE_PURE_FUNCTION std::string FormatTime(Time t);
+#if ABSL_HAVE_CPP_ATTRIBUTE(gnu::pure)
+#define ABSL_ATTRIBUTE_PURE_FUNCTION [[gnu::pure]]
+#elif ABSL_HAVE_ATTRIBUTE(pure)
+#define ABSL_ATTRIBUTE_PURE_FUNCTION __attribute__((pure))
+#else
+// If the attribute isn't defined, we'll fallback to ABSL_MUST_USE_RESULT since
+// pure functions are useless if its return is ignored.
+#define ABSL_ATTRIBUTE_PURE_FUNCTION ABSL_MUST_USE_RESULT
+#endif
+
+// ABSL_ATTRIBUTE_CONST_FUNCTION
+//
+// ABSL_ATTRIBUTE_CONST_FUNCTION is used to annotate declarations of "const"
+// functions. A const function is similar to a pure function, with one
+// exception: Pure functions may return value that depend on a non-volatile
+// object that isn't provided as a function argument, while the const function
+// is guaranteed to return the same result given the same arguments.
+//
+// Example:
+//
+//  ABSL_ATTRIBUTE_CONST_FUNCTION int64_t ToInt64Milliseconds(Duration d);
+#if defined(_MSC_VER) && !defined(__clang__)
+// Put the MSVC case first since MSVC seems to parse const as a C++ keyword.
+#define ABSL_ATTRIBUTE_CONST_FUNCTION ABSL_ATTRIBUTE_PURE_FUNCTION
+#elif ABSL_HAVE_CPP_ATTRIBUTE(gnu::const)
+#define ABSL_ATTRIBUTE_CONST_FUNCTION [[gnu::const]]
+#elif ABSL_HAVE_ATTRIBUTE(const)
+#define ABSL_ATTRIBUTE_CONST_FUNCTION __attribute__((const))
+#else
+// Since const functions are more restrictive pure function, we'll fallback to a
+// pure function if the const attribute is not handled.
+#define ABSL_ATTRIBUTE_CONST_FUNCTION ABSL_ATTRIBUTE_PURE_FUNCTION
+#endif
 
 // ABSL_ATTRIBUTE_LIFETIME_BOUND indicates that a resource owned by a function
 // parameter or implicit object parameter is retained by the return value of the
@@ -800,15 +843,11 @@
 // See also the upstream documentation:
 // https://clang.llvm.org/docs/AttributeReference.html#trivial-abi
 //
-#if ABSL_HAVE_CPP_ATTRIBUTE(clang::trivial_abi)
-#define ABSL_ATTRIBUTE_TRIVIAL_ABI [[clang::trivial_abi]]
-#define ABSL_HAVE_ATTRIBUTE_TRIVIAL_ABI 1
-#elif ABSL_HAVE_ATTRIBUTE(trivial_abi)
-#define ABSL_ATTRIBUTE_TRIVIAL_ABI __attribute__((trivial_abi))
-#define ABSL_HAVE_ATTRIBUTE_TRIVIAL_ABI 1
-#else
+// b/321691395 - This is currently disabled in open-source builds since
+// compiler support differs. If system libraries compiled with GCC are mixed
+// with libraries compiled with Clang, types will have different ideas about
+// their ABI, leading to hard to debug crashes.
 #define ABSL_ATTRIBUTE_TRIVIAL_ABI
-#endif
 
 // ABSL_ATTRIBUTE_NO_UNIQUE_ADDRESS
 //
diff --git a/contrib/restricted/abseil-cpp/absl/base/call_once.h b/contrib/restricted/abseil-cpp/absl/base/call_once.h
index 08436bac8a..7b0e69ccd5 100644
--- a/contrib/restricted/abseil-cpp/absl/base/call_once.h
+++ b/contrib/restricted/abseil-cpp/absl/base/call_once.h
@@ -37,6 +37,7 @@
 #include "absl/base/internal/scheduling_mode.h"
 #include "absl/base/internal/spinlock_wait.h"
 #include "absl/base/macros.h"
+#include "absl/base/nullability.h"
 #include "absl/base/optimization.h"
 #include "absl/base/port.h"
 
@@ -46,7 +47,8 @@ ABSL_NAMESPACE_BEGIN
 class once_flag;
 
 namespace base_internal {
-std::atomic<uint32_t>* ControlWord(absl::once_flag* flag);
+absl::Nonnull<std::atomic<uint32_t>*> ControlWord(
+    absl::Nonnull<absl::once_flag*> flag);
 }  // namespace base_internal
 
 // call_once()
@@ -89,7 +91,8 @@ class once_flag {
   once_flag& operator=(const once_flag&) = delete;
 
  private:
-  friend std::atomic<uint32_t>* base_internal::ControlWord(once_flag* flag);
+  friend absl::Nonnull<std::atomic<uint32_t>*> base_internal::ControlWord(
+      absl::Nonnull<once_flag*> flag);
   std::atomic<uint32_t> control_;
 };
 
@@ -103,7 +106,8 @@ namespace base_internal {
 // Like call_once, but uses KERNEL_ONLY scheduling. Intended to be used to
 // initialize entities used by the scheduler implementation.
 template <typename Callable, typename... Args>
-void LowLevelCallOnce(absl::once_flag* flag, Callable&& fn, Args&&... args);
+void LowLevelCallOnce(absl::Nonnull<absl::once_flag*> flag, Callable&& fn,
+                      Args&&... args);
 
 // Disables scheduling while on stack when scheduling mode is non-cooperative.
 // No effect for cooperative scheduling modes.
@@ -143,10 +147,10 @@ enum {
 };
 
 template <typename Callable, typename... Args>
-ABSL_ATTRIBUTE_NOINLINE
-void CallOnceImpl(std::atomic<uint32_t>* control,
-                  base_internal::SchedulingMode scheduling_mode, Callable&& fn,
-                  Args&&... args) {
+ABSL_ATTRIBUTE_NOINLINE void CallOnceImpl(
+    absl::Nonnull<std::atomic<uint32_t>*> control,
+    base_internal::SchedulingMode scheduling_mode, Callable&& fn,
+    Args&&... args) {
 #ifndef NDEBUG
   {
     uint32_t old_control = control->load(std::memory_order_relaxed);
@@ -185,12 +189,14 @@ void CallOnceImpl(std::atomic<uint32_t>* control,
   }  // else *control is already kOnceDone
 }
 
-inline std::atomic<uint32_t>* ControlWord(once_flag* flag) {
+inline absl::Nonnull<std::atomic<uint32_t>*> ControlWord(
+    absl::Nonnull<once_flag*> flag) {
   return &flag->control_;
 }
 
 template <typename Callable, typename... Args>
-void LowLevelCallOnce(absl::once_flag* flag, Callable&& fn, Args&&... args) {
+void LowLevelCallOnce(absl::Nonnull<absl::once_flag*> flag, Callable&& fn,
+                      Args&&... args) {
   std::atomic<uint32_t>* once = base_internal::ControlWord(flag);
   uint32_t s = once->load(std::memory_order_acquire);
   if (ABSL_PREDICT_FALSE(s != base_internal::kOnceDone)) {
diff --git a/contrib/restricted/abseil-cpp/absl/base/casts.h b/contrib/restricted/abseil-cpp/absl/base/casts.h
index d19588852f..e0b11bbe49 100644
--- a/contrib/restricted/abseil-cpp/absl/base/casts.h
+++ b/contrib/restricted/abseil-cpp/absl/base/casts.h
@@ -90,7 +90,7 @@ ABSL_NAMESPACE_BEGIN
 //
 // Such implicit cast chaining may be useful within template logic.
 template <typename To>
-constexpr To implicit_cast(typename absl::internal::identity_t<To> to) {
+constexpr To implicit_cast(typename absl::internal::type_identity_t<To> to) {
   return to;
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/base/config.h b/contrib/restricted/abseil-cpp/absl/base/config.h
index 334e2767ac..8bd9a6d586 100644
--- a/contrib/restricted/abseil-cpp/absl/base/config.h
+++ b/contrib/restricted/abseil-cpp/absl/base/config.h
@@ -75,6 +75,12 @@
 #define ABSL_INTERNAL_CPLUSPLUS_LANG __cplusplus
 #endif
 
+#if defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
+    ABSL_INTERNAL_CPLUSPLUS_LANG >= 202002L
+// Include library feature test macros.
+#include <version>
+#endif
+
 #if defined(__APPLE__)
 // Included for TARGET_OS_IPHONE, __IPHONE_OS_VERSION_MIN_REQUIRED,
 // __IPHONE_8_0.
@@ -111,8 +117,8 @@
 //
 // LTS releases can be obtained from
 // https://github.com/abseil/abseil-cpp/releases.
-#define ABSL_LTS_RELEASE_VERSION 20230802
-#define ABSL_LTS_RELEASE_PATCH_LEVEL 1
+#define ABSL_LTS_RELEASE_VERSION 20240116
+#define ABSL_LTS_RELEASE_PATCH_LEVEL 0
 
 // Helper macro to convert a CPP variable to a string literal.
 #define ABSL_INTERNAL_DO_TOKEN_STR(x) #x
@@ -332,8 +338,8 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 #ifdef ABSL_HAVE_INTRINSIC_INT128
 #error ABSL_HAVE_INTRINSIC_INT128 cannot be directly set
 #elif defined(__SIZEOF_INT128__)
-#if (defined(__clang__) && !defined(_WIN32)) || \
-    (defined(__CUDACC__) && __CUDACC_VER_MAJOR__ >= 9) ||                \
+#if (defined(__clang__) && !defined(_WIN32)) ||           \
+    (defined(__CUDACC__) && __CUDACC_VER_MAJOR__ >= 9) || \
     (defined(__GNUC__) && !defined(__clang__) && !defined(__CUDACC__))
 #define ABSL_HAVE_INTRINSIC_INT128 1
 #elif defined(__CUDACC__)
@@ -395,7 +401,7 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 //   Windows                           _WIN32
 //   NaCL                              __native_client__
 //   AsmJS                             __asmjs__
-//   WebAssembly                       __wasm__
+//   WebAssembly (Emscripten)          __EMSCRIPTEN__
 //   Fuchsia                           __Fuchsia__
 //
 // Note that since Android defines both __ANDROID__ and __linux__, one
@@ -407,11 +413,11 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // POSIX.1-2001.
 #ifdef ABSL_HAVE_MMAP
 #error ABSL_HAVE_MMAP cannot be directly set
-#elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \
-    defined(_AIX) || defined(__ros__) || defined(__native_client__) ||    \
-    defined(__asmjs__) || defined(__wasm__) || defined(__Fuchsia__) ||    \
-    defined(__sun) || defined(__ASYLO__) || defined(__myriad2__) ||       \
-    defined(__HAIKU__) || defined(__OpenBSD__) || defined(__NetBSD__) ||  \
+#elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) ||    \
+    defined(_AIX) || defined(__ros__) || defined(__native_client__) ||       \
+    defined(__asmjs__) || defined(__EMSCRIPTEN__) || defined(__Fuchsia__) || \
+    defined(__sun) || defined(__ASYLO__) || defined(__myriad2__) ||          \
+    defined(__HAIKU__) || defined(__OpenBSD__) || defined(__NetBSD__) ||     \
     defined(__QNX__) || defined(__VXWORKS__) || defined(__hexagon__)
 #define ABSL_HAVE_MMAP 1
 #endif
@@ -484,6 +490,8 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // https://sourceforge.net/p/mingw-w64/mingw-w64/ci/master/tree/mingw-w64-crt/misc/alarm.c
 #elif defined(__EMSCRIPTEN__)
 // emscripten doesn't support signals
+#elif defined(__wasi__)
+// WASI doesn't support signals
 #elif defined(__Fuchsia__)
 // Signals don't exist on fuchsia.
 #elif defined(__native_client__)
@@ -536,14 +544,14 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // and
 // https://github.com/llvm/llvm-project/commit/0bc451e7e137c4ccadcd3377250874f641ca514a
 // The second has the actually correct versions, thus, is what we copy here.
-#if defined(__APPLE__) &&                                           \
-    ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) &&     \
-      __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101300) ||    \
-     (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) &&    \
-      __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 120000) ||   \
-     (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) &&     \
-      __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 50000) ||     \
-     (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) &&        \
+#if defined(__APPLE__) &&                                         \
+    ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) &&   \
+      __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101300) ||  \
+     (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) &&  \
+      __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 120000) || \
+     (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) &&   \
+      __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 50000) ||   \
+     (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) &&      \
       __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 120000))
 #define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 1
 #else
@@ -555,7 +563,7 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // Checks whether C++17 std::any is available.
 #ifdef ABSL_HAVE_STD_ANY
 #error "ABSL_HAVE_STD_ANY cannot be directly set."
-#elif defined(__cpp_lib_any)
+#elif defined(__cpp_lib_any) && __cpp_lib_any >= 201606L
 #define ABSL_HAVE_STD_ANY 1
 #elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L && \
@@ -568,9 +576,9 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // Checks whether C++17 std::optional is available.
 #ifdef ABSL_HAVE_STD_OPTIONAL
 #error "ABSL_HAVE_STD_OPTIONAL cannot be directly set."
-#elif defined(__cpp_lib_optional)
+#elif defined(__cpp_lib_optional) && __cpp_lib_optional >= 202106L
 #define ABSL_HAVE_STD_OPTIONAL 1
-#elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) &&  \
+#elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L && \
     !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
 #define ABSL_HAVE_STD_OPTIONAL 1
@@ -581,7 +589,7 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // Checks whether C++17 std::variant is available.
 #ifdef ABSL_HAVE_STD_VARIANT
 #error "ABSL_HAVE_STD_VARIANT cannot be directly set."
-#elif defined(__cpp_lib_variant)
+#elif defined(__cpp_lib_variant) && __cpp_lib_variant >= 201606L
 #define ABSL_HAVE_STD_VARIANT 1
 #elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L && \
@@ -594,13 +602,29 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // Checks whether C++17 std::string_view is available.
 #ifdef ABSL_HAVE_STD_STRING_VIEW
 #error "ABSL_HAVE_STD_STRING_VIEW cannot be directly set."
-#elif defined(__cpp_lib_string_view)
+#elif defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L
 #define ABSL_HAVE_STD_STRING_VIEW 1
 #elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L
 #define ABSL_HAVE_STD_STRING_VIEW 1
 #endif
 
+// ABSL_HAVE_STD_ORDERING
+//
+// Checks whether C++20 std::{partial,weak,strong}_ordering are available.
+//
+// __cpp_lib_three_way_comparison is missing on libc++
+// (https://github.com/llvm/llvm-project/issues/73953) so treat it as defined
+// when building in C++20 mode.
+#ifdef ABSL_HAVE_STD_ORDERING
+#error "ABSL_HAVE_STD_ORDERING cannot be directly set."
+#elif (defined(__cpp_lib_three_way_comparison) &&    \
+       __cpp_lib_three_way_comparison >= 201907L) || \
+    (defined(ABSL_INTERNAL_CPLUSPLUS_LANG) &&        \
+     ABSL_INTERNAL_CPLUSPLUS_LANG >= 202002L)
+#define ABSL_HAVE_STD_ORDERING 1
+#endif
+
 // ABSL_USES_STD_ANY
 //
 // Indicates whether absl::any is an alias for std::any.
@@ -663,6 +687,22 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 #error options.h is misconfigured.
 #endif
 
+// ABSL_USES_STD_ORDERING
+//
+// Indicates whether absl::{partial,weak,strong}_ordering are aliases for the
+// std:: ordering types.
+#if !defined(ABSL_OPTION_USE_STD_ORDERING)
+#error options.h is misconfigured.
+#elif ABSL_OPTION_USE_STD_ORDERING == 0 || \
+    (ABSL_OPTION_USE_STD_ORDERING == 2 && !defined(ABSL_HAVE_STD_ORDERING))
+#undef ABSL_USES_STD_ORDERING
+#elif ABSL_OPTION_USE_STD_ORDERING == 1 || \
+    (ABSL_OPTION_USE_STD_ORDERING == 2 && defined(ABSL_HAVE_STD_ORDERING))
+#define ABSL_USES_STD_ORDERING 1
+#else
+#error options.h is misconfigured.
+#endif
+
 // In debug mode, MSVC 2017's std::variant throws a EXCEPTION_ACCESS_VIOLATION
 // SEH exception from emplace for variant<SomeStruct> when constructing the
 // struct can throw. This defeats some of variant_test and
@@ -845,11 +885,30 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 // RTTI support.
 #ifdef ABSL_INTERNAL_HAS_RTTI
 #error ABSL_INTERNAL_HAS_RTTI cannot be directly set
-#elif (defined(__GNUC__) && defined(__GXX_RTTI)) || \
-    (defined(_MSC_VER) && defined(_CPPRTTI)) ||     \
-    (!defined(__GNUC__) && !defined(_MSC_VER))
+#elif ABSL_HAVE_FEATURE(cxx_rtti)
+#define ABSL_INTERNAL_HAS_RTTI 1
+#elif defined(__GNUC__) && defined(__GXX_RTTI)
 #define ABSL_INTERNAL_HAS_RTTI 1
-#endif  // !defined(__GNUC__) || defined(__GXX_RTTI)
+#elif defined(_MSC_VER) && defined(_CPPRTTI)
+#define ABSL_INTERNAL_HAS_RTTI 1
+#elif !defined(__GNUC__) && !defined(_MSC_VER)
+// Unknown compiler, default to RTTI
+#define ABSL_INTERNAL_HAS_RTTI 1
+#endif
+
+// `ABSL_INTERNAL_HAS_CXA_DEMANGLE` determines whether `abi::__cxa_demangle` is
+// available.
+#ifdef ABSL_INTERNAL_HAS_CXA_DEMANGLE
+#error ABSL_INTERNAL_HAS_CXA_DEMANGLE cannot be directly set
+#elif defined(OS_ANDROID) && (defined(__i386__) || defined(__x86_64__))
+#define ABSL_INTERNAL_HAS_CXA_DEMANGLE 0
+#elif defined(__GNUC__) && defined(__GNUC_MINOR__) &&            \
+    (__GNUC__ >= 4 || (__GNUC__ >= 3 && __GNUC_MINOR__ >= 4)) && \
+    !defined(__mips__)
+#define ABSL_INTERNAL_HAS_CXA_DEMANGLE 1
+#elif defined(__clang__) && !defined(_MSC_VER)
+#define ABSL_INTERNAL_HAS_CXA_DEMANGLE 1
+#endif
 
 // ABSL_INTERNAL_HAVE_SSE is used for compile-time detection of SSE support.
 // See https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html for an overview of
@@ -936,8 +995,8 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
 #if __EMSCRIPTEN_tiny__ >= 1000
 #error __EMSCRIPTEN_tiny__ is too big to fit in ABSL_INTERNAL_EMSCRIPTEN_VERSION
 #endif
-#define ABSL_INTERNAL_EMSCRIPTEN_VERSION                          \
-  ((__EMSCRIPTEN_major__)*1000000 + (__EMSCRIPTEN_minor__)*1000 + \
+#define ABSL_INTERNAL_EMSCRIPTEN_VERSION                              \
+  ((__EMSCRIPTEN_major__) * 1000000 + (__EMSCRIPTEN_minor__) * 1000 + \
    (__EMSCRIPTEN_tiny__))
 #endif
 #endif
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/endian.h b/contrib/restricted/abseil-cpp/absl/base/internal/endian.h
index 50747d75ec..943f3d97e7 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/endian.h
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/endian.h
@@ -22,6 +22,7 @@
 #include "absl/base/casts.h"
 #include "absl/base/config.h"
 #include "absl/base/internal/unaligned_access.h"
+#include "absl/base/nullability.h"
 #include "absl/base/port.h"
 
 namespace absl {
@@ -160,27 +161,27 @@ inline int64_t ToHost(int64_t x) {
 }
 
 // Functions to do unaligned loads and stores in little-endian order.
-inline uint16_t Load16(const void *p) {
+inline uint16_t Load16(absl::Nonnull<const void *> p) {
   return ToHost16(ABSL_INTERNAL_UNALIGNED_LOAD16(p));
 }
 
-inline void Store16(void *p, uint16_t v) {
+inline void Store16(absl::Nonnull<void *> p, uint16_t v) {
   ABSL_INTERNAL_UNALIGNED_STORE16(p, FromHost16(v));
 }
 
-inline uint32_t Load32(const void *p) {
+inline uint32_t Load32(absl::Nonnull<const void *> p) {
   return ToHost32(ABSL_INTERNAL_UNALIGNED_LOAD32(p));
 }
 
-inline void Store32(void *p, uint32_t v) {
+inline void Store32(absl::Nonnull<void *> p, uint32_t v) {
   ABSL_INTERNAL_UNALIGNED_STORE32(p, FromHost32(v));
 }
 
-inline uint64_t Load64(const void *p) {
+inline uint64_t Load64(absl::Nonnull<const void *> p) {
   return ToHost64(ABSL_INTERNAL_UNALIGNED_LOAD64(p));
 }
 
-inline void Store64(void *p, uint64_t v) {
+inline void Store64(absl::Nonnull<void *> p, uint64_t v) {
   ABSL_INTERNAL_UNALIGNED_STORE64(p, FromHost64(v));
 }
 
@@ -250,27 +251,27 @@ inline int64_t ToHost(int64_t x) {
 }
 
 // Functions to do unaligned loads and stores in big-endian order.
-inline uint16_t Load16(const void *p) {
+inline uint16_t Load16(absl::Nonnull<const void *> p) {
   return ToHost16(ABSL_INTERNAL_UNALIGNED_LOAD16(p));
 }
 
-inline void Store16(void *p, uint16_t v) {
+inline void Store16(absl::Nonnull<void *> p, uint16_t v) {
   ABSL_INTERNAL_UNALIGNED_STORE16(p, FromHost16(v));
 }
 
-inline uint32_t Load32(const void *p) {
+inline uint32_t Load32(absl::Nonnull<const void *> p) {
   return ToHost32(ABSL_INTERNAL_UNALIGNED_LOAD32(p));
 }
 
-inline void Store32(void *p, uint32_t v) {
+inline void Store32(absl::Nonnull<void *>p, uint32_t v) {
   ABSL_INTERNAL_UNALIGNED_STORE32(p, FromHost32(v));
 }
 
-inline uint64_t Load64(const void *p) {
+inline uint64_t Load64(absl::Nonnull<const void *> p) {
   return ToHost64(ABSL_INTERNAL_UNALIGNED_LOAD64(p));
 }
 
-inline void Store64(void *p, uint64_t v) {
+inline void Store64(absl::Nonnull<void *> p, uint64_t v) {
   ABSL_INTERNAL_UNALIGNED_STORE64(p, FromHost64(v));
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/identity.h b/contrib/restricted/abseil-cpp/absl/base/internal/identity.h
index a3154ed7bc..365207b7e7 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/identity.h
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/identity.h
@@ -22,13 +22,15 @@ namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace internal {
 
+// This is a back-fill of C++20's `std::type_identity`.
 template <typename T>
-struct identity {
+struct type_identity {
   typedef T type;
 };
 
+// This is a back-fill of C++20's `std::type_identity_t`.
 template <typename T>
-using identity_t = typename identity<T>::type;
+using type_identity_t = typename type_identity<T>::type;
 
 }  // namespace internal
 ABSL_NAMESPACE_END
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/inline_variable.h b/contrib/restricted/abseil-cpp/absl/base/internal/inline_variable.h
index df933faff5..09daf0f5b7 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/inline_variable.h
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/inline_variable.h
@@ -63,12 +63,12 @@
 // Bug: https://bugs.llvm.org/show_bug.cgi?id=35862
 //
 // Note:
-//   identity_t is used here so that the const and name are in the
+//   type_identity_t is used here so that the const and name are in the
 //   appropriate place for pointer types, reference types, function pointer
 //   types, etc..
 #if defined(__clang__)
 #define ABSL_INTERNAL_EXTERN_DECL(type, name) \
-  extern const ::absl::internal::identity_t<type> name;
+  extern const ::absl::internal::type_identity_t<type> name;
 #else  // Otherwise, just define the macro to do nothing.
 #define ABSL_INTERNAL_EXTERN_DECL(type, name)
 #endif  // defined(__clang__)
@@ -76,30 +76,31 @@
 // See above comment at top of file for details.
 #define ABSL_INTERNAL_INLINE_CONSTEXPR(type, name, init) \
   ABSL_INTERNAL_EXTERN_DECL(type, name)                  \
-  inline constexpr ::absl::internal::identity_t<type> name = init
+  inline constexpr ::absl::internal::type_identity_t<type> name = init
 
 #else
 
 // See above comment at top of file for details.
 //
 // Note:
-//   identity_t is used here so that the const and name are in the
+//   type_identity_t is used here so that the const and name are in the
 //   appropriate place for pointer types, reference types, function pointer
 //   types, etc..
-#define ABSL_INTERNAL_INLINE_CONSTEXPR(var_type, name, init)                  \
-  template <class /*AbslInternalDummy*/ = void>                               \
-  struct AbslInternalInlineVariableHolder##name {                             \
-    static constexpr ::absl::internal::identity_t<var_type> kInstance = init; \
-  };                                                                          \
-                                                                              \
-  template <class AbslInternalDummy>                                          \
-  constexpr ::absl::internal::identity_t<var_type>                            \
-      AbslInternalInlineVariableHolder##name<AbslInternalDummy>::kInstance;   \
-                                                                              \
-  static constexpr const ::absl::internal::identity_t<var_type>&              \
-      name = /* NOLINT */                                                     \
-      AbslInternalInlineVariableHolder##name<>::kInstance;                    \
-  static_assert(sizeof(void (*)(decltype(name))) != 0,                        \
+#define ABSL_INTERNAL_INLINE_CONSTEXPR(var_type, name, init)                 \
+  template <class /*AbslInternalDummy*/ = void>                              \
+  struct AbslInternalInlineVariableHolder##name {                            \
+    static constexpr ::absl::internal::type_identity_t<var_type> kInstance = \
+        init;                                                                \
+  };                                                                         \
+                                                                             \
+  template <class AbslInternalDummy>                                         \
+  constexpr ::absl::internal::type_identity_t<var_type>                      \
+      AbslInternalInlineVariableHolder##name<AbslInternalDummy>::kInstance;  \
+                                                                             \
+  static constexpr const ::absl::internal::type_identity_t<var_type>&        \
+      name = /* NOLINT */                                                    \
+      AbslInternalInlineVariableHolder##name<>::kInstance;                   \
+  static_assert(sizeof(void (*)(decltype(name))) != 0,                       \
                 "Silence unused variable warnings.")
 
 #endif  // __cpp_inline_variables
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/low_level_alloc.cc b/contrib/restricted/abseil-cpp/absl/base/internal/low_level_alloc.cc
index 6d2cfeac3c..a563f7b9f9 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/low_level_alloc.cc
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/low_level_alloc.cc
@@ -329,7 +329,7 @@ size_t GetPageSize() {
   SYSTEM_INFO system_info;
   GetSystemInfo(&system_info);
   return std::max(system_info.dwPageSize, system_info.dwAllocationGranularity);
-#elif defined(__wasm__) || defined(__asmjs__)
+#elif defined(__wasm__) || defined(__asmjs__) || defined(__hexagon__)
   return getpagesize();
 #else
   return static_cast<size_t>(sysconf(_SC_PAGESIZE));
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/nullability_impl.h b/contrib/restricted/abseil-cpp/absl/base/internal/nullability_impl.h
new file mode 100644
index 0000000000..36e1b33d65
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/nullability_impl.h
@@ -0,0 +1,106 @@
+// Copyright 2023 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef ABSL_BASE_INTERNAL_NULLABILITY_IMPL_H_
+#define ABSL_BASE_INTERNAL_NULLABILITY_IMPL_H_
+
+#include <memory>
+#include <type_traits>
+
+#include "absl/base/attributes.h"
+#include "absl/meta/type_traits.h"
+
+namespace absl {
+
+namespace nullability_internal {
+
+// `IsNullabilityCompatible` checks whether its first argument is a class
+// explicitly tagged as supporting nullability annotations. The tag is the type
+// declaration `absl_nullability_compatible`.
+template <typename, typename = void>
+struct IsNullabilityCompatible : std::false_type {};
+
+template <typename T>
+struct IsNullabilityCompatible<
+    T, absl::void_t<typename T::absl_nullability_compatible>> : std::true_type {
+};
+
+template <typename T>
+constexpr bool IsSupportedType = IsNullabilityCompatible<T>::value;
+
+template <typename T>
+constexpr bool IsSupportedType<T*> = true;
+
+template <typename T, typename U>
+constexpr bool IsSupportedType<T U::*> = true;
+
+template <typename T, typename... Deleter>
+constexpr bool IsSupportedType<std::unique_ptr<T, Deleter...>> = true;
+
+template <typename T>
+constexpr bool IsSupportedType<std::shared_ptr<T>> = true;
+
+template <typename T>
+struct EnableNullable {
+  static_assert(nullability_internal::IsSupportedType<std::remove_cv_t<T>>,
+                "Template argument must be a raw or supported smart pointer "
+                "type. See absl/base/nullability.h.");
+  using type = T;
+};
+
+template <typename T>
+struct EnableNonnull {
+  static_assert(nullability_internal::IsSupportedType<std::remove_cv_t<T>>,
+                "Template argument must be a raw or supported smart pointer "
+                "type. See absl/base/nullability.h.");
+  using type = T;
+};
+
+template <typename T>
+struct EnableNullabilityUnknown {
+  static_assert(nullability_internal::IsSupportedType<std::remove_cv_t<T>>,
+                "Template argument must be a raw or supported smart pointer "
+                "type. See absl/base/nullability.h.");
+  using type = T;
+};
+
+// Note: we do not apply Clang nullability attributes (e.g. _Nullable).  These
+// only support raw pointers, and conditionally enabling them only for raw
+// pointers inhibits template arg deduction.  Ideally, they would support all
+// pointer-like types.
+template <typename T, typename = typename EnableNullable<T>::type>
+using NullableImpl
+#if ABSL_HAVE_CPP_ATTRIBUTE(clang::annotate)
+    [[clang::annotate("Nullable")]]
+#endif
+    = T;
+
+template <typename T, typename = typename EnableNonnull<T>::type>
+using NonnullImpl
+#if ABSL_HAVE_CPP_ATTRIBUTE(clang::annotate)
+    [[clang::annotate("Nonnull")]]
+#endif
+    = T;
+
+template <typename T, typename = typename EnableNullabilityUnknown<T>::type>
+using NullabilityUnknownImpl
+#if ABSL_HAVE_CPP_ATTRIBUTE(clang::annotate)
+    [[clang::annotate("Nullability_Unspecified")]]
+#endif
+    = T;
+
+}  // namespace nullability_internal
+}  // namespace absl
+
+#endif  // ABSL_BASE_INTERNAL_NULLABILITY_IMPL_H_
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.cc b/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.cc
index a1ca876d4e..6f68002a3c 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.cc
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.cc
@@ -42,8 +42,9 @@
 // This preprocessor token is also defined in raw_io.cc.  If you need to copy
 // this, consider moving both to config.h instead.
 #if defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \
-    defined(__Fuchsia__) || defined(__native_client__) ||               \
-    defined(__OpenBSD__) || defined(__EMSCRIPTEN__) || defined(__ASYLO__)
+    defined(__hexagon__) || defined(__Fuchsia__) ||                     \
+    defined(__native_client__) || defined(__OpenBSD__) ||               \
+    defined(__EMSCRIPTEN__) || defined(__ASYLO__)
 
 #include <unistd.h>
 
@@ -56,8 +57,7 @@
 // ABSL_HAVE_SYSCALL_WRITE is defined when the platform provides the syscall
 //   syscall(SYS_write, /*int*/ fd, /*char* */ buf, /*size_t*/ len);
 // for low level operations that want to avoid libc.
-#if (defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__)) && \
-    !defined(__ANDROID__)
+#if (defined(__linux__) || defined(__FreeBSD__)) && !defined(__ANDROID__)
 #include <sys/syscall.h>
 #define ABSL_HAVE_SYSCALL_WRITE 1
 #define ABSL_LOW_LEVEL_WRITE_SUPPORTED 1
@@ -93,8 +93,7 @@ constexpr char kTruncated[] = " ... (message truncated)\n";
 bool VADoRawLog(char** buf, int* size, const char* format, va_list ap)
     ABSL_PRINTF_ATTRIBUTE(3, 0);
 bool VADoRawLog(char** buf, int* size, const char* format, va_list ap) {
-  if (*size < 0)
-    return false;
+  if (*size < 0) return false;
   int n = vsnprintf(*buf, static_cast<size_t>(*size), format, ap);
   bool result = true;
   if (n < 0 || n > *size) {
@@ -122,8 +121,7 @@ constexpr int kLogBufSize = 3000;
 bool DoRawLog(char** buf, int* size, const char* format, ...)
     ABSL_PRINTF_ATTRIBUTE(3, 4);
 bool DoRawLog(char** buf, int* size, const char* format, ...) {
-  if (*size < 0)
-    return false;
+  if (*size < 0) return false;
   va_list ap;
   va_start(ap, format);
   int n = vsnprintf(*buf, static_cast<size_t>(*size), format, ap);
@@ -242,8 +240,8 @@ void AsyncSignalSafeWriteError(const char* s, size_t len) {
   _write(/* stderr */ 2, s, static_cast<unsigned>(len));
 #else
   // stderr logging unsupported on this platform
-  (void) s;
-  (void) len;
+  (void)s;
+  (void)len;
 #endif
 }
 
@@ -258,7 +256,7 @@ void RawLog(absl::LogSeverity severity, const char* file, int line,
 bool RawLoggingFullySupported() {
 #ifdef ABSL_LOW_LEVEL_WRITE_SUPPORTED
   return true;
-#else  // !ABSL_LOW_LEVEL_WRITE_SUPPORTED
+#else   // !ABSL_LOW_LEVEL_WRITE_SUPPORTED
   return false;
 #endif  // !ABSL_LOW_LEVEL_WRITE_SUPPORTED
 }
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.h b/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.h
index b79550b2b7..d7cfbc576b 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.h
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/raw_logging.h
@@ -108,6 +108,7 @@
 #define ABSL_RAW_LOG_INTERNAL_WARNING ::absl::LogSeverity::kWarning
 #define ABSL_RAW_LOG_INTERNAL_ERROR ::absl::LogSeverity::kError
 #define ABSL_RAW_LOG_INTERNAL_FATAL ::absl::LogSeverity::kFatal
+#define ABSL_RAW_LOG_INTERNAL_DFATAL ::absl::kLogDebugFatal
 #define ABSL_RAW_LOG_INTERNAL_LEVEL(severity) \
   ::absl::NormalizeLogSeverity(severity)
 
@@ -115,6 +116,7 @@
 #define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_WARNING
 #define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_ERROR
 #define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_FATAL ABSL_UNREACHABLE()
+#define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_DFATAL
 #define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_LEVEL(severity)
 
 namespace absl {
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/spinlock.h b/contrib/restricted/abseil-cpp/absl/base/internal/spinlock.h
index 09ba5824b1..2929cd6f5c 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/spinlock.h
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/spinlock.h
@@ -19,10 +19,10 @@
 //   - for use by Abseil internal code that Mutex itself depends on
 //   - for async signal safety (see below)
 
-// SpinLock is async signal safe.  If a spinlock is used within a signal
-// handler, all code that acquires the lock must ensure that the signal cannot
-// arrive while they are holding the lock.  Typically, this is done by blocking
-// the signal.
+// SpinLock with a base_internal::SchedulingMode::SCHEDULE_KERNEL_ONLY is async
+// signal safe. If a spinlock is used within a signal handler, all code that
+// acquires the lock must ensure that the signal cannot arrive while they are
+// holding the lock. Typically, this is done by blocking the signal.
 //
 // Threads waiting on a SpinLock may be woken in an arbitrary order.
 
@@ -41,6 +41,14 @@
 #include "absl/base/internal/tsan_mutex_interface.h"
 #include "absl/base/thread_annotations.h"
 
+namespace tcmalloc {
+namespace tcmalloc_internal {
+
+class AllocationGuardSpinLockHolder;
+
+}  // namespace tcmalloc_internal
+}  // namespace tcmalloc
+
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace base_internal {
@@ -137,6 +145,7 @@ class ABSL_LOCKABLE SpinLock {
 
   // Provide access to protected method above.  Use for testing only.
   friend struct SpinLockTest;
+  friend class tcmalloc::tcmalloc_internal::AllocationGuardSpinLockHolder;
 
  private:
   // lockword_ is used to store the following:
@@ -171,6 +180,10 @@ class ABSL_LOCKABLE SpinLock {
     return scheduling_mode == base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL;
   }
 
+  bool IsCooperative() const {
+    return lockword_.load(std::memory_order_relaxed) & kSpinLockCooperative;
+  }
+
   uint32_t TryLockInternal(uint32_t lock_value, uint32_t wait_cycles);
   void SlowLock() ABSL_ATTRIBUTE_COLD;
   void SlowUnlock(uint32_t lock_value) ABSL_ATTRIBUTE_COLD;
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/thread_annotations.h b/contrib/restricted/abseil-cpp/absl/base/internal/thread_annotations.h
deleted file mode 100644
index 8c5c67e0df..0000000000
--- a/contrib/restricted/abseil-cpp/absl/base/internal/thread_annotations.h
+++ /dev/null
@@ -1,280 +0,0 @@
-// Copyright 2019 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-// -----------------------------------------------------------------------------
-// File: thread_annotations.h
-// -----------------------------------------------------------------------------
-//
-// WARNING: This is a backwards compatible header and it will be removed after
-// the migration to prefixed thread annotations is finished; please include
-// "absl/base/thread_annotations.h".
-//
-// This header file contains macro definitions for thread safety annotations
-// that allow developers to document the locking policies of multi-threaded
-// code. The annotations can also help program analysis tools to identify
-// potential thread safety issues.
-//
-// These annotations are implemented using compiler attributes. Using the macros
-// defined here instead of raw attributes allow for portability and future
-// compatibility.
-//
-// When referring to mutexes in the arguments of the attributes, you should
-// use variable names or more complex expressions (e.g. my_object->mutex_)
-// that evaluate to a concrete mutex object whenever possible. If the mutex
-// you want to refer to is not in scope, you may use a member pointer
-// (e.g. &MyClass::mutex_) to refer to a mutex in some (unknown) object.
-
-#ifndef ABSL_BASE_INTERNAL_THREAD_ANNOTATIONS_H_
-#define ABSL_BASE_INTERNAL_THREAD_ANNOTATIONS_H_
-
-// ABSL_LEGACY_THREAD_ANNOTATIONS is a *temporary* compatibility macro that can
-// be defined on the compile command-line to restore the legacy spellings of the
-// thread annotations macros/functions. The macros in this file are available
-// under ABSL_ prefixed spellings in absl/base/thread_annotations.h. This macro
-// and the legacy spellings will be removed in the future.
-#ifdef ABSL_LEGACY_THREAD_ANNOTATIONS
-
-#if defined(__clang__)
-#define THREAD_ANNOTATION_ATTRIBUTE__(x)   __attribute__((x))
-#else
-#define THREAD_ANNOTATION_ATTRIBUTE__(x)   // no-op
-#endif
-
-// GUARDED_BY()
-//
-// Documents if a shared field or global variable needs to be protected by a
-// mutex. GUARDED_BY() allows the user to specify a particular mutex that
-// should be held when accessing the annotated variable.
-//
-// Although this annotation (and PT_GUARDED_BY, below) cannot be applied to
-// local variables, a local variable and its associated mutex can often be
-// combined into a small class or struct, thereby allowing the annotation.
-//
-// Example:
-//
-//   class Foo {
-//     Mutex mu_;
-//     int p1_ GUARDED_BY(mu_);
-//     ...
-//   };
-#define GUARDED_BY(x) THREAD_ANNOTATION_ATTRIBUTE__(guarded_by(x))
-
-// PT_GUARDED_BY()
-//
-// Documents if the memory location pointed to by a pointer should be guarded
-// by a mutex when dereferencing the pointer.
-//
-// Example:
-//   class Foo {
-//     Mutex mu_;
-//     int *p1_ PT_GUARDED_BY(mu_);
-//     ...
-//   };
-//
-// Note that a pointer variable to a shared memory location could itself be a
-// shared variable.
-//
-// Example:
-//
-//   // `q_`, guarded by `mu1_`, points to a shared memory location that is
-//   // guarded by `mu2_`:
-//   int *q_ GUARDED_BY(mu1_) PT_GUARDED_BY(mu2_);
-#define PT_GUARDED_BY(x) THREAD_ANNOTATION_ATTRIBUTE__(pt_guarded_by(x))
-
-// ACQUIRED_AFTER() / ACQUIRED_BEFORE()
-//
-// Documents the acquisition order between locks that can be held
-// simultaneously by a thread. For any two locks that need to be annotated
-// to establish an acquisition order, only one of them needs the annotation.
-// (i.e. You don't have to annotate both locks with both ACQUIRED_AFTER
-// and ACQUIRED_BEFORE.)
-//
-// As with GUARDED_BY, this is only applicable to mutexes that are shared
-// fields or global variables.
-//
-// Example:
-//
-//   Mutex m1_;
-//   Mutex m2_ ACQUIRED_AFTER(m1_);
-#define ACQUIRED_AFTER(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(acquired_after(__VA_ARGS__))
-
-#define ACQUIRED_BEFORE(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(acquired_before(__VA_ARGS__))
-
-// EXCLUSIVE_LOCKS_REQUIRED() / SHARED_LOCKS_REQUIRED()
-//
-// Documents a function that expects a mutex to be held prior to entry.
-// The mutex is expected to be held both on entry to, and exit from, the
-// function.
-//
-// An exclusive lock allows read-write access to the guarded data member(s), and
-// only one thread can acquire a lock exclusively at any one time. A shared lock
-// allows read-only access, and any number of threads can acquire a shared lock
-// concurrently.
-//
-// Generally, non-const methods should be annotated with
-// EXCLUSIVE_LOCKS_REQUIRED, while const methods should be annotated with
-// SHARED_LOCKS_REQUIRED.
-//
-// Example:
-//
-//   Mutex mu1, mu2;
-//   int a GUARDED_BY(mu1);
-//   int b GUARDED_BY(mu2);
-//
-//   void foo() EXCLUSIVE_LOCKS_REQUIRED(mu1, mu2) { ... }
-//   void bar() const SHARED_LOCKS_REQUIRED(mu1, mu2) { ... }
-#define EXCLUSIVE_LOCKS_REQUIRED(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(exclusive_locks_required(__VA_ARGS__))
-
-#define SHARED_LOCKS_REQUIRED(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(shared_locks_required(__VA_ARGS__))
-
-// LOCKS_EXCLUDED()
-//
-// Documents the locks acquired in the body of the function. These locks
-// cannot be held when calling this function (as Abseil's `Mutex` locks are
-// non-reentrant).
-#define LOCKS_EXCLUDED(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(locks_excluded(__VA_ARGS__))
-
-// LOCK_RETURNED()
-//
-// Documents a function that returns a mutex without acquiring it.  For example,
-// a public getter method that returns a pointer to a private mutex should
-// be annotated with LOCK_RETURNED.
-#define LOCK_RETURNED(x) \
-  THREAD_ANNOTATION_ATTRIBUTE__(lock_returned(x))
-
-// LOCKABLE
-//
-// Documents if a class/type is a lockable type (such as the `Mutex` class).
-#define LOCKABLE \
-  THREAD_ANNOTATION_ATTRIBUTE__(lockable)
-
-// SCOPED_LOCKABLE
-//
-// Documents if a class does RAII locking (such as the `MutexLock` class).
-// The constructor should use `LOCK_FUNCTION()` to specify the mutex that is
-// acquired, and the destructor should use `UNLOCK_FUNCTION()` with no
-// arguments; the analysis will assume that the destructor unlocks whatever the
-// constructor locked.
-#define SCOPED_LOCKABLE \
-  THREAD_ANNOTATION_ATTRIBUTE__(scoped_lockable)
-
-// EXCLUSIVE_LOCK_FUNCTION()
-//
-// Documents functions that acquire a lock in the body of a function, and do
-// not release it.
-#define EXCLUSIVE_LOCK_FUNCTION(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(exclusive_lock_function(__VA_ARGS__))
-
-// SHARED_LOCK_FUNCTION()
-//
-// Documents functions that acquire a shared (reader) lock in the body of a
-// function, and do not release it.
-#define SHARED_LOCK_FUNCTION(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(shared_lock_function(__VA_ARGS__))
-
-// UNLOCK_FUNCTION()
-//
-// Documents functions that expect a lock to be held on entry to the function,
-// and release it in the body of the function.
-#define UNLOCK_FUNCTION(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(unlock_function(__VA_ARGS__))
-
-// EXCLUSIVE_TRYLOCK_FUNCTION() / SHARED_TRYLOCK_FUNCTION()
-//
-// Documents functions that try to acquire a lock, and return success or failure
-// (or a non-boolean value that can be interpreted as a boolean).
-// The first argument should be `true` for functions that return `true` on
-// success, or `false` for functions that return `false` on success. The second
-// argument specifies the mutex that is locked on success. If unspecified, this
-// mutex is assumed to be `this`.
-#define EXCLUSIVE_TRYLOCK_FUNCTION(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(exclusive_trylock_function(__VA_ARGS__))
-
-#define SHARED_TRYLOCK_FUNCTION(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(shared_trylock_function(__VA_ARGS__))
-
-// ASSERT_EXCLUSIVE_LOCK() / ASSERT_SHARED_LOCK()
-//
-// Documents functions that dynamically check to see if a lock is held, and fail
-// if it is not held.
-#define ASSERT_EXCLUSIVE_LOCK(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(assert_exclusive_lock(__VA_ARGS__))
-
-#define ASSERT_SHARED_LOCK(...) \
-  THREAD_ANNOTATION_ATTRIBUTE__(assert_shared_lock(__VA_ARGS__))
-
-// NO_THREAD_SAFETY_ANALYSIS
-//
-// Turns off thread safety checking within the body of a particular function.
-// This annotation is used to mark functions that are known to be correct, but
-// the locking behavior is more complicated than the analyzer can handle.
-#define NO_THREAD_SAFETY_ANALYSIS \
-  THREAD_ANNOTATION_ATTRIBUTE__(no_thread_safety_analysis)
-
-//------------------------------------------------------------------------------
-// Tool-Supplied Annotations
-//------------------------------------------------------------------------------
-
-// TS_UNCHECKED should be placed around lock expressions that are not valid
-// C++ syntax, but which are present for documentation purposes.  These
-// annotations will be ignored by the analysis.
-#define TS_UNCHECKED(x) ""
-
-// TS_FIXME is used to mark lock expressions that are not valid C++ syntax.
-// It is used by automated tools to mark and disable invalid expressions.
-// The annotation should either be fixed, or changed to TS_UNCHECKED.
-#define TS_FIXME(x) ""
-
-// Like NO_THREAD_SAFETY_ANALYSIS, this turns off checking within the body of
-// a particular function.  However, this attribute is used to mark functions
-// that are incorrect and need to be fixed.  It is used by automated tools to
-// avoid breaking the build when the analysis is updated.
-// Code owners are expected to eventually fix the routine.
-#define NO_THREAD_SAFETY_ANALYSIS_FIXME  NO_THREAD_SAFETY_ANALYSIS
-
-// Similar to NO_THREAD_SAFETY_ANALYSIS_FIXME, this macro marks a GUARDED_BY
-// annotation that needs to be fixed, because it is producing thread safety
-// warning.  It disables the GUARDED_BY.
-#define GUARDED_BY_FIXME(x)
-
-// Disables warnings for a single read operation.  This can be used to avoid
-// warnings when it is known that the read is not actually involved in a race,
-// but the compiler cannot confirm that.
-#define TS_UNCHECKED_READ(x) thread_safety_analysis::ts_unchecked_read(x)
-
-
-namespace thread_safety_analysis {
-
-// Takes a reference to a guarded data member, and returns an unguarded
-// reference.
-template <typename T>
-inline const T& ts_unchecked_read(const T& v) NO_THREAD_SAFETY_ANALYSIS {
-  return v;
-}
-
-template <typename T>
-inline T& ts_unchecked_read(T& v) NO_THREAD_SAFETY_ANALYSIS {
-  return v;
-}
-
-}  // namespace thread_safety_analysis
-
-#endif  // defined(ABSL_LEGACY_THREAD_ANNOTATIONS)
-
-#endif  // ABSL_BASE_INTERNAL_THREAD_ANNOTATIONS_H_
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/thread_identity.cc b/contrib/restricted/abseil-cpp/absl/base/internal/thread_identity.cc
index 252443ebcd..0471a25dce 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/thread_identity.cc
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/thread_identity.cc
@@ -16,8 +16,12 @@
 
 #if !defined(_WIN32) || defined(__MINGW32__)
 #include <pthread.h>
+#ifndef __wasi__
+// WASI does not provide this header, either way we disable use
+// of signals with it below.
 #include <signal.h>
 #endif
+#endif
 
 #include <atomic>
 #include <cassert>
@@ -80,10 +84,12 @@ void SetCurrentThreadIdentity(ThreadIdentity* identity,
   absl::call_once(init_thread_identity_key_once, AllocateThreadIdentityKey,
                   reclaimer);
 
-#if defined(__EMSCRIPTEN__) || defined(__MINGW32__) || defined(__hexagon__)
-  // Emscripten and MinGW pthread implementations does not support signals.
-  // See https://kripken.github.io/emscripten-site/docs/porting/pthreads.html
-  // for more information.
+#if defined(__wasi__) || defined(__EMSCRIPTEN__) || defined(__MINGW32__) || \
+    defined(__hexagon__)
+  // Emscripten, WASI and MinGW pthread implementations does not support
+  // signals. See
+  // https://kripken.github.io/emscripten-site/docs/porting/pthreads.html for
+  // more information.
   pthread_setspecific(thread_identity_pthread_key,
                       reinterpret_cast<void*>(identity));
 #else
diff --git a/contrib/restricted/abseil-cpp/absl/base/internal/unaligned_access.h b/contrib/restricted/abseil-cpp/absl/base/internal/unaligned_access.h
index 093dd9b499..4fea457491 100644
--- a/contrib/restricted/abseil-cpp/absl/base/internal/unaligned_access.h
+++ b/contrib/restricted/abseil-cpp/absl/base/internal/unaligned_access.h
@@ -23,6 +23,7 @@
 
 #include "absl/base/attributes.h"
 #include "absl/base/config.h"
+#include "absl/base/nullability.h"
 
 // unaligned APIs
 
@@ -35,29 +36,35 @@ namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace base_internal {
 
-inline uint16_t UnalignedLoad16(const void *p) {
+inline uint16_t UnalignedLoad16(absl::Nonnull<const void *> p) {
   uint16_t t;
   memcpy(&t, p, sizeof t);
   return t;
 }
 
-inline uint32_t UnalignedLoad32(const void *p) {
+inline uint32_t UnalignedLoad32(absl::Nonnull<const void *> p) {
   uint32_t t;
   memcpy(&t, p, sizeof t);
   return t;
 }
 
-inline uint64_t UnalignedLoad64(const void *p) {
+inline uint64_t UnalignedLoad64(absl::Nonnull<const void *> p) {
   uint64_t t;
   memcpy(&t, p, sizeof t);
   return t;
 }
 
-inline void UnalignedStore16(void *p, uint16_t v) { memcpy(p, &v, sizeof v); }
+inline void UnalignedStore16(absl::Nonnull<void *> p, uint16_t v) {
+  memcpy(p, &v, sizeof v);
+}
 
-inline void UnalignedStore32(void *p, uint32_t v) { memcpy(p, &v, sizeof v); }
+inline void UnalignedStore32(absl::Nonnull<void *> p, uint32_t v) {
+  memcpy(p, &v, sizeof v);
+}
 
-inline void UnalignedStore64(void *p, uint64_t v) { memcpy(p, &v, sizeof v); }
+inline void UnalignedStore64(absl::Nonnull<void *> p, uint64_t v) {
+  memcpy(p, &v, sizeof v);
+}
 
 }  // namespace base_internal
 ABSL_NAMESPACE_END
diff --git a/contrib/restricted/abseil-cpp/absl/base/log_severity.cc b/contrib/restricted/abseil-cpp/absl/base/log_severity.cc
index 60a8fc1f89..8e7bbbc9e0 100644
--- a/contrib/restricted/abseil-cpp/absl/base/log_severity.cc
+++ b/contrib/restricted/abseil-cpp/absl/base/log_severity.cc
@@ -17,6 +17,7 @@
 #include <ostream>
 
 #include "absl/base/attributes.h"
+#include "absl/base/config.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
diff --git a/contrib/restricted/abseil-cpp/absl/base/log_severity.h b/contrib/restricted/abseil-cpp/absl/base/log_severity.h
index 8bdca38b5f..de9702ab68 100644
--- a/contrib/restricted/abseil-cpp/absl/base/log_severity.h
+++ b/contrib/restricted/abseil-cpp/absl/base/log_severity.h
@@ -64,6 +64,8 @@ ABSL_NAMESPACE_BEGIN
 //   --my_log_level=info
 //   --my_log_level=0
 //
+// `DFATAL` and `kLogDebugFatal` are similarly accepted.
+//
 // Unparsing a flag produces the same result as `absl::LogSeverityName()` for
 // the standard levels and a base-ten integer otherwise.
 enum class LogSeverity : int {
@@ -82,18 +84,28 @@ constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
            absl::LogSeverity::kError, absl::LogSeverity::kFatal}};
 }
 
+// `absl::kLogDebugFatal` equals `absl::LogSeverity::kFatal` in debug builds
+// (i.e. when `NDEBUG` is not defined) and `absl::LogSeverity::kError`
+// otherwise.  Avoid ODR-using this variable as it has internal linkage and thus
+// distinct storage in different TUs.
+#ifdef NDEBUG
+static constexpr absl::LogSeverity kLogDebugFatal = absl::LogSeverity::kError;
+#else
+static constexpr absl::LogSeverity kLogDebugFatal = absl::LogSeverity::kFatal;
+#endif
+
 // LogSeverityName()
 //
 // Returns the all-caps string representation (e.g. "INFO") of the specified
 // severity level if it is one of the standard levels and "UNKNOWN" otherwise.
 constexpr const char* LogSeverityName(absl::LogSeverity s) {
-  return s == absl::LogSeverity::kInfo
-             ? "INFO"
-             : s == absl::LogSeverity::kWarning
-                   ? "WARNING"
-                   : s == absl::LogSeverity::kError
-                         ? "ERROR"
-                         : s == absl::LogSeverity::kFatal ? "FATAL" : "UNKNOWN";
+  switch (s) {
+    case absl::LogSeverity::kInfo: return "INFO";
+    case absl::LogSeverity::kWarning: return "WARNING";
+    case absl::LogSeverity::kError: return "ERROR";
+    case absl::LogSeverity::kFatal: return "FATAL";
+  }
+  return "UNKNOWN";
 }
 
 // NormalizeLogSeverity()
@@ -101,9 +113,10 @@ constexpr const char* LogSeverityName(absl::LogSeverity s) {
 // Values less than `kInfo` normalize to `kInfo`; values greater than `kFatal`
 // normalize to `kError` (**NOT** `kFatal`).
 constexpr absl::LogSeverity NormalizeLogSeverity(absl::LogSeverity s) {
-  return s < absl::LogSeverity::kInfo
-             ? absl::LogSeverity::kInfo
-             : s > absl::LogSeverity::kFatal ? absl::LogSeverity::kError : s;
+  absl::LogSeverity n = s;
+  if (n < absl::LogSeverity::kInfo) n = absl::LogSeverity::kInfo;
+  if (n > absl::LogSeverity::kFatal) n = absl::LogSeverity::kError;
+  return n;
 }
 constexpr absl::LogSeverity NormalizeLogSeverity(int s) {
   return absl::NormalizeLogSeverity(static_cast<absl::LogSeverity>(s));
diff --git a/contrib/restricted/abseil-cpp/absl/base/no_destructor.h b/contrib/restricted/abseil-cpp/absl/base/no_destructor.h
new file mode 100644
index 0000000000..d4b16a6e88
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/base/no_destructor.h
@@ -0,0 +1,217 @@
+// Copyright 2023 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: no_destructor.h
+// -----------------------------------------------------------------------------
+//
+// This header file defines the absl::NoDestructor<T> wrapper for defining a
+// static type that does not need to be destructed upon program exit. Instead,
+// such an object survives during program exit (and can be safely accessed at
+// any time).
+//
+// Objects of such type, if constructed safely and under the right conditions,
+// provide two main benefits over other alternatives:
+//
+//   * Global objects not normally allowed due to concerns of destruction order
+//     (i.e. no "complex globals") can be safely allowed, provided that such
+//     objects can be constant initialized.
+//   * Function scope static objects can be optimized to avoid heap allocation,
+//     pointer chasing, and allow lazy construction.
+//
+// See below for complete details.
+
+
+#ifndef ABSL_BASE_NO_DESTRUCTOR_H_
+#define ABSL_BASE_NO_DESTRUCTOR_H_
+
+#include <new>
+#include <type_traits>
+#include <utility>
+
+#include "absl/base/config.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+
+// absl::NoDestructor<T>
+//
+// NoDestructor<T> is a wrapper around an object of type T that behaves as an
+// object of type T but never calls T's destructor. NoDestructor<T> makes it
+// safer and/or more efficient to use such objects in static storage contexts:
+// as global or function scope static variables.
+//
+// An instance of absl::NoDestructor<T> has similar type semantics to an
+// instance of T:
+//
+// * Constructs in the same manner as an object of type T through perfect
+//   forwarding.
+// * Provides pointer/reference semantic access to the object of type T via
+//   `->`, `*`, and `get()`.
+//   (Note that `const NoDestructor<T>` works like a pointer to const `T`.)
+//
+// An object of type NoDestructor<T> should be defined in static storage:
+// as either a global static object, or as a function scope static variable.
+//
+// Additionally, NoDestructor<T> provides the following benefits:
+//
+// * Never calls T's destructor for the object
+// * If the object is a function-local static variable, the type can be
+//   lazily constructed.
+//
+// An object of type NoDestructor<T> is "trivially destructible" in the notion
+// that its destructor is never run. Provided that an object of this type can be
+// safely initialized and does not need to be cleaned up on program shutdown,
+// NoDestructor<T> allows you to define global static variables, since Google's
+// C++ style guide ban on such objects doesn't apply to objects that are
+// trivially destructible.
+//
+// Usage as Global Static Variables
+//
+// NoDestructor<T> allows declaration of a global object with a non-trivial
+// constructor in static storage without needing to add a destructor.
+// However, such objects still need to worry about initialization order, so
+// such objects should be const initialized:
+//
+//    // Global or namespace scope.
+//    ABSL_CONST_INIT absl::NoDestructor<MyRegistry> reg{"foo", "bar", 8008};
+//
+// Note that if your object already has a trivial destructor, you don't need to
+// use NoDestructor<T>.
+//
+// Usage as Function Scope Static Variables
+//
+// Function static objects will be lazily initialized within static storage:
+//
+//    // Function scope.
+//    const std::string& MyString() {
+//      static const absl::NoDestructor<std::string> x("foo");
+//      return *x;
+//    }
+//
+// For function static variables, NoDestructor avoids heap allocation and can be
+// inlined in static storage, resulting in exactly-once, thread-safe
+// construction of an object, and very fast access thereafter (the cost is a few
+// extra cycles).
+//
+// Using NoDestructor<T> in this manner is generally better than other patterns
+// which require pointer chasing:
+//
+//   // Prefer using absl::NoDestructor<T> instead for the static variable.
+//   const std::string& MyString() {
+//     static const std::string* x = new std::string("foo");
+//     return *x;
+//   }
+//
+template <typename T>
+class NoDestructor {
+ public:
+  // Forwards arguments to the T's constructor: calls T(args...).
+  template <typename... Ts,
+            // Disable this overload when it might collide with copy/move.
+            typename std::enable_if<!std::is_same<void(std::decay_t<Ts>&...),
+                                                  void(NoDestructor&)>::value,
+                                    int>::type = 0>
+  explicit constexpr NoDestructor(Ts&&... args)
+      : impl_(std::forward<Ts>(args)...) {}
+
+  // Forwards copy and move construction for T. Enables usage like this:
+  //   static NoDestructor<std::array<string, 3>> x{{{"1", "2", "3"}}};
+  //   static NoDestructor<std::vector<int>> x{{1, 2, 3}};
+  explicit constexpr NoDestructor(const T& x) : impl_(x) {}
+  explicit constexpr NoDestructor(T&& x)
+      : impl_(std::move(x)) {}
+
+  // No copying.
+  NoDestructor(const NoDestructor&) = delete;
+  NoDestructor& operator=(const NoDestructor&) = delete;
+
+  // Pretend to be a smart pointer to T with deep constness.
+  // Never returns a null pointer.
+  T& operator*() { return *get(); }
+  T* operator->() { return get(); }
+  T* get() { return impl_.get(); }
+  const T& operator*() const { return *get(); }
+  const T* operator->() const { return get(); }
+  const T* get() const { return impl_.get(); }
+
+ private:
+  class DirectImpl {
+   public:
+    template <typename... Args>
+    explicit constexpr DirectImpl(Args&&... args)
+        : value_(std::forward<Args>(args)...) {}
+    const T* get() const { return &value_; }
+    T* get() { return &value_; }
+
+   private:
+    T value_;
+  };
+
+  class PlacementImpl {
+   public:
+    template <typename... Args>
+    explicit PlacementImpl(Args&&... args) {
+      new (&space_) T(std::forward<Args>(args)...);
+    }
+    const T* get() const {
+      return Launder(reinterpret_cast<const T*>(&space_));
+    }
+    T* get() { return Launder(reinterpret_cast<T*>(&space_)); }
+
+   private:
+    template <typename P>
+    static P* Launder(P* p) {
+#if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606L
+      return std::launder(p);
+#elif ABSL_HAVE_BUILTIN(__builtin_launder)
+      return __builtin_launder(p);
+#else
+      // When `std::launder` or equivalent are not available, we rely on
+      // undefined behavior, which works as intended on Abseil's officially
+      // supported platforms as of Q3 2023.
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstrict-aliasing"
+#endif
+      return p;
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+#endif
+    }
+
+    alignas(T) unsigned char space_[sizeof(T)];
+  };
+
+  // If the object is trivially destructible we use a member directly to avoid
+  // potential once-init runtime initialization. It somewhat defeats the
+  // purpose of NoDestructor in this case, but this makes the class more
+  // friendly to generic code.
+  std::conditional_t<std::is_trivially_destructible<T>::value, DirectImpl,
+                     PlacementImpl>
+      impl_;
+};
+
+#ifdef ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION
+// Provide 'Class Template Argument Deduction': the type of NoDestructor's T
+// will be the same type as the argument passed to NoDestructor's constructor.
+template <typename T>
+NoDestructor(T) -> NoDestructor<T>;
+#endif  // ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION
+
+ABSL_NAMESPACE_END
+}  // namespace absl
+
+#endif  // ABSL_BASE_NO_DESTRUCTOR_H_
diff --git a/contrib/restricted/abseil-cpp/absl/base/nullability.h b/contrib/restricted/abseil-cpp/absl/base/nullability.h
new file mode 100644
index 0000000000..6f49b6f535
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/base/nullability.h
@@ -0,0 +1,224 @@
+// Copyright 2023 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: nullability.h
+// -----------------------------------------------------------------------------
+//
+// This header file defines a set of "templated annotations" for designating the
+// expected nullability of pointers. These annotations allow you to designate
+// pointers in one of three classification states:
+//
+//  * "Non-null" (for pointers annotated `Nonnull<T>`), indicating that it is
+//    invalid for the given pointer to ever be null.
+//  * "Nullable" (for pointers annotated `Nullable<T>`), indicating that it is
+//    valid for the given pointer to be null.
+//  * "Unknown" (for pointers annotated `NullabilityUnknown<T>`), indicating
+//    that the given pointer has not been yet classified as either nullable or
+//    non-null. This is the default state of unannotated pointers.
+//
+// NOTE: unannotated pointers implicitly bear the annotation
+// `NullabilityUnknown<T>`; you should rarely, if ever, see this annotation used
+// in the codebase explicitly.
+//
+// -----------------------------------------------------------------------------
+// Nullability and Contracts
+// -----------------------------------------------------------------------------
+//
+// These nullability annotations allow you to more clearly specify contracts on
+// software components by narrowing the *preconditions*, *postconditions*, and
+// *invariants* of pointer state(s) in any given interface. It then depends on
+// context who is responsible for fulfilling the annotation's requirements.
+//
+// For example, a function may receive a pointer argument. Designating that
+// pointer argument as "non-null" tightens the precondition of the contract of
+// that function. It is then the responsibility of anyone calling such a
+// function to ensure that the passed pointer is not null.
+//
+// Similarly, a function may have a pointer as a return value. Designating that
+// return value as "non-null" tightens the postcondition of the contract of that
+// function. In this case, however, it is the responsibility of the function
+// itself to ensure that the returned pointer is not null.
+//
+// Clearly defining these contracts allows providers (and consumers) of such
+// pointers to have more confidence in their null state. If a function declares
+// a return value as "non-null", for example, the caller should not need to
+// check whether the returned value is `nullptr`; it can simply assume the
+// pointer is valid.
+//
+// Of course most interfaces already have expectations on the nullability state
+// of pointers, and these expectations are, in effect, a contract; often,
+// however, those contracts are either poorly or partially specified, assumed,
+// or misunderstood. These nullability annotations are designed to allow you to
+// formalize those contracts within the codebase.
+//
+// -----------------------------------------------------------------------------
+// Using Nullability Annotations
+// -----------------------------------------------------------------------------
+//
+// It is important to note that these annotations are not distinct strong
+// *types*. They are alias templates defined to be equal to the underlying
+// pointer type. A pointer annotated `Nonnull<T*>`, for example, is simply a
+// pointer of type `T*`. Each annotation acts as a form of documentation about
+// the contract for the given pointer. Each annotation requires providers or
+// consumers of these pointers across API boundaries to take appropriate steps
+// when setting or using these pointers:
+//
+// * "Non-null" pointers should never be null. It is the responsibility of the
+//   provider of this pointer to ensure that the pointer may never be set to
+//   null. Consumers of such pointers can treat such pointers as non-null.
+// * "Nullable" pointers may or may not be null. Consumers of such pointers
+//   should precede any usage of that pointer (e.g. a dereference operation)
+//   with a a `nullptr` check.
+// * "Unknown" pointers may be either "non-null" or "nullable" but have not been
+//   definitively determined to be in either classification state. Providers of
+//   such pointers across API boundaries should determine --  over time -- to
+//   annotate the pointer in either of the above two states. Consumers of such
+//   pointers across an API boundary should continue to treat such pointers as
+//   they currently do.
+//
+// Example:
+//
+// // PaySalary() requires the passed pointer to an `Employee` to be non-null.
+// void PaySalary(absl::Nonnull<Employee *> e) {
+//   pay(e->salary);  // OK to dereference
+// }
+//
+// // CompleteTransaction() guarantees the returned pointer to an `Account` to
+// // be non-null.
+// absl::Nonnull<Account *> balance CompleteTransaction(double fee) {
+// ...
+// }
+//
+// // Note that specifying a nullability annotation does not prevent someone
+// // from violating the contract:
+//
+// Nullable<Employee *> find(Map& employees, std::string_view name);
+//
+// void g(Map& employees) {
+//   Employee *e = find(employees, "Pat");
+//   // `e` can now be null.
+//   PaySalary(e); // Violates contract, but compiles!
+// }
+//
+// Nullability annotations, in other words, are useful for defining and
+// narrowing contracts; *enforcement* of those contracts depends on use and any
+// additional (static or dynamic analysis) tooling.
+//
+// NOTE: The "unknown" annotation state indicates that a pointer's contract has
+// not yet been positively identified. The unknown state therefore acts as a
+// form of documentation of your technical debt, and a codebase that adopts
+// nullability annotations should aspire to annotate every pointer as either
+// "non-null" or "nullable".
+//
+// -----------------------------------------------------------------------------
+// Applicability of Nullability Annotations
+// -----------------------------------------------------------------------------
+//
+// By default, nullability annotations are applicable to raw and smart
+// pointers. User-defined types can indicate compatibility with nullability
+// annotations by providing an `absl_nullability_compatible` nested type. The
+// actual definition of this inner type is not relevant as it is used merely as
+// a marker. It is common to use a using declaration of
+// `absl_nullability_compatible` set to void.
+//
+// // Example:
+// struct MyPtr {
+//   using absl_nullability_compatible = void;
+//   ...
+// };
+//
+// DISCLAIMER:
+// ===========================================================================
+// These nullability annotations are primarily a human readable signal about the
+// intended contract of the pointer. They are not *types* and do not currently
+// provide any correctness guarantees. For example, a pointer annotated as
+// `Nonnull<T*>` is *not guaranteed* to be non-null, and the compiler won't
+// alert or prevent assignment of a `Nullable<T*>` to a `Nonnull<T*>`.
+// ===========================================================================
+#ifndef ABSL_BASE_NULLABILITY_H_
+#define ABSL_BASE_NULLABILITY_H_
+
+#include "absl/base/internal/nullability_impl.h"
+
+namespace absl {
+
+// absl::Nonnull
+//
+// The indicated pointer is never null. It is the responsibility of the provider
+// of this pointer across an API boundary to ensure that the pointer is never be
+// set to null. Consumers of this pointer across an API boundary may safely
+// dereference the pointer.
+//
+// Example:
+//
+// // `employee` is designated as not null.
+// void PaySalary(absl::Nonnull<Employee *> employee) {
+//   pay(*employee);  // OK to dereference
+// }
+template <typename T>
+using Nonnull = nullability_internal::NonnullImpl<T>;
+
+// absl::Nullable
+//
+// The indicated pointer may, by design, be either null or non-null. Consumers
+// of this pointer across an API boundary should perform a `nullptr` check
+// before performing any operation using the pointer.
+//
+// Example:
+//
+// // `employee` may  be null.
+// void PaySalary(absl::Nullable<Employee *> employee) {
+//   if (employee != nullptr) {
+//     Pay(*employee);  // OK to dereference
+//   }
+// }
+template <typename T>
+using Nullable = nullability_internal::NullableImpl<T>;
+
+// absl::NullabilityUnknown (default)
+//
+// The indicated pointer has not yet been determined to be definitively
+// "non-null" or "nullable." Providers of such pointers across API boundaries
+// should, over time, annotate such pointers as either "non-null" or "nullable."
+// Consumers of these pointers across an API boundary should treat such pointers
+// with the same caution they treat currently unannotated pointers. Most
+// existing code will have "unknown"  pointers, which should eventually be
+// migrated into one of the above two nullability states: `Nonnull<T>` or
+//  `Nullable<T>`.
+//
+// NOTE: Because this annotation is the global default state, pointers without
+// any annotation are assumed to have "unknown" semantics. This assumption is
+// designed to minimize churn and reduce clutter within the codebase.
+//
+// Example:
+//
+// // `employee`s nullability state is unknown.
+// void PaySalary(absl::NullabilityUnknown<Employee *> employee) {
+//   Pay(*employee); // Potentially dangerous. API provider should investigate.
+// }
+//
+// Note that a pointer without an annotation, by default, is assumed to have the
+// annotation `NullabilityUnknown`.
+//
+// // `employee`s nullability state is unknown.
+// void PaySalary(Employee* employee) {
+//   Pay(*employee); // Potentially dangerous. API provider should investigate.
+// }
+template <typename T>
+using NullabilityUnknown = nullability_internal::NullabilityUnknownImpl<T>;
+
+}  // namespace absl
+
+#endif  // ABSL_BASE_NULLABILITY_H_
diff --git a/contrib/restricted/abseil-cpp/absl/base/optimization.h b/contrib/restricted/abseil-cpp/absl/base/optimization.h
index ad0121ad3b..f985995899 100644
--- a/contrib/restricted/abseil-cpp/absl/base/optimization.h
+++ b/contrib/restricted/abseil-cpp/absl/base/optimization.h
@@ -25,6 +25,7 @@
 #include <assert.h>
 
 #include "absl/base/config.h"
+#include "absl/base/options.h"
 
 // ABSL_BLOCK_TAIL_CALL_OPTIMIZATION
 //
diff --git a/contrib/restricted/abseil-cpp/absl/base/options.h b/contrib/restricted/abseil-cpp/absl/base/options.h
index f308e1bf8b..d7bf8cffe6 100644
--- a/contrib/restricted/abseil-cpp/absl/base/options.h
+++ b/contrib/restricted/abseil-cpp/absl/base/options.h
@@ -176,6 +176,32 @@
 
 #define ABSL_OPTION_USE_STD_VARIANT 2
 
+// ABSL_OPTION_USE_STD_ORDERING
+//
+// This option controls whether absl::{partial,weak,strong}_ordering are
+// implemented as aliases to the std:: ordering types, or as an independent
+// implementation.
+//
+// A value of 0 means to use Abseil's implementation.  This requires only C++11
+// support, and is expected to work on every toolchain we support.
+//
+// A value of 1 means to use aliases.  This requires that all code using Abseil
+// is built in C++20 mode or later.
+//
+// A value of 2 means to detect the C++ version being used to compile Abseil,
+// and use an alias only if working std:: ordering types are available.  This
+// option is useful when you are building your program from source.  It should
+// not be used otherwise -- for example, if you are distributing Abseil in a
+// binary package manager -- since in mode 2, they will name different types,
+// with different mangled names and binary layout, depending on the compiler
+// flags passed by the end user.  For more info, see
+// https://abseil.io/about/design/dropin-types.
+//
+// User code should not inspect this macro.  To check in the preprocessor if
+// the ordering types are aliases of std:: ordering types, use the feature macro
+// ABSL_USES_STD_ORDERING.
+
+#define ABSL_OPTION_USE_STD_ORDERING 2
 
 // ABSL_OPTION_USE_INLINE_NAMESPACE
 // ABSL_OPTION_INLINE_NAMESPACE_NAME
@@ -200,7 +226,7 @@
 // allowed.
 
 #define ABSL_OPTION_USE_INLINE_NAMESPACE 1
-#define ABSL_OPTION_INLINE_NAMESPACE_NAME lts_20230802
+#define ABSL_OPTION_INLINE_NAMESPACE_NAME lts_20240116
 
 // ABSL_OPTION_HARDENED
 //
diff --git a/contrib/restricted/abseil-cpp/absl/base/prefetch.h b/contrib/restricted/abseil-cpp/absl/base/prefetch.h
index de7a180d60..eb40a4453c 100644
--- a/contrib/restricted/abseil-cpp/absl/base/prefetch.h
+++ b/contrib/restricted/abseil-cpp/absl/base/prefetch.h
@@ -24,17 +24,19 @@
 #ifndef ABSL_BASE_PREFETCH_H_
 #define ABSL_BASE_PREFETCH_H_
 
+#include "absl/base/attributes.h"
 #include "absl/base/config.h"
 
 #if defined(ABSL_INTERNAL_HAVE_SSE)
 #include <xmmintrin.h>
 #endif
 
-#if defined(_MSC_VER) && _MSC_VER >= 1900 && \
-    (defined(_M_X64) || defined(_M_IX86))
+#if defined(_MSC_VER)
 #include <intrin.h>
+#if defined(ABSL_INTERNAL_HAVE_SSE)
 #pragma intrinsic(_mm_prefetch)
 #endif
+#endif
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -140,21 +142,24 @@ void PrefetchToLocalCacheForWrite(const void* addr);
 // See __builtin_prefetch:
 // https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html.
 //
-inline void PrefetchToLocalCache(const void* addr) {
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCache(
+    const void* addr) {
   __builtin_prefetch(addr, 0, 3);
 }
 
-inline void PrefetchToLocalCacheNta(const void* addr) {
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheNta(
+    const void* addr) {
   __builtin_prefetch(addr, 0, 0);
 }
 
-inline void PrefetchToLocalCacheForWrite(const void* addr) {
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheForWrite(
+    const void* addr) {
   // [x86] gcc/clang don't generate PREFETCHW for __builtin_prefetch(.., 1)
   // unless -march=broadwell or newer; this is not generally the default, so we
   // manually emit prefetchw. PREFETCHW is recognized as a no-op on older Intel
   // processors and has been present on AMD processors since the K6-2.
-#if defined(__x86_64__)
-  asm("prefetchw (%0)" : : "r"(addr));
+#if defined(__x86_64__) && !defined(__PRFCHW__)
+  asm("prefetchw %0" : : "m"(*reinterpret_cast<const char*>(addr)));
 #else
   __builtin_prefetch(addr, 1, 3);
 #endif
@@ -164,15 +169,18 @@ inline void PrefetchToLocalCacheForWrite(const void* addr) {
 
 #define ABSL_HAVE_PREFETCH 1
 
-inline void PrefetchToLocalCache(const void* addr) {
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCache(
+    const void* addr) {
   _mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_T0);
 }
 
-inline void PrefetchToLocalCacheNta(const void* addr) {
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheNta(
+    const void* addr) {
   _mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_NTA);
 }
 
-inline void PrefetchToLocalCacheForWrite(const void* addr) {
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheForWrite(
+    const void* addr) {
 #if defined(_MM_HINT_ET0)
   _mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_ET0);
 #elif !defined(_MSC_VER) && defined(__x86_64__)
@@ -180,15 +188,18 @@ inline void PrefetchToLocalCacheForWrite(const void* addr) {
   // up, PREFETCHW is recognized as a no-op on older Intel processors
   // and has been present on AMD processors since the K6-2. We have this
   // disabled for MSVC compilers as this miscompiles on older MSVC compilers.
-  asm("prefetchw (%0)" : : "r"(addr));
+  asm("prefetchw %0" : : "m"(*reinterpret_cast<const char*>(addr)));
 #endif
 }
 
 #else
 
-inline void PrefetchToLocalCache(const void* addr) {}
-inline void PrefetchToLocalCacheNta(const void* addr) {}
-inline void PrefetchToLocalCacheForWrite(const void* addr) {}
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCache(
+    const void* addr) {}
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheNta(
+    const void* addr) {}
+ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheForWrite(
+    const void* addr) {}
 
 #endif
 
diff --git a/contrib/restricted/abseil-cpp/absl/base/thread_annotations.h b/contrib/restricted/abseil-cpp/absl/base/thread_annotations.h
index bc8a620347..4a3f3e33e9 100644
--- a/contrib/restricted/abseil-cpp/absl/base/thread_annotations.h
+++ b/contrib/restricted/abseil-cpp/absl/base/thread_annotations.h
@@ -36,8 +36,6 @@
 
 #include "absl/base/attributes.h"
 #include "absl/base/config.h"
-// TODO(mbonadei): Remove after the backward compatibility period.
-#include "absl/base/internal/thread_annotations.h"  // IWYU pragma: export
 
 // ABSL_GUARDED_BY()
 //
diff --git a/contrib/restricted/abseil-cpp/absl/container/flat_hash_map.h b/contrib/restricted/abseil-cpp/absl/container/flat_hash_map.h
index 8f4d993911..acd013b026 100644
--- a/contrib/restricted/abseil-cpp/absl/container/flat_hash_map.h
+++ b/contrib/restricted/abseil-cpp/absl/container/flat_hash_map.h
@@ -64,7 +64,7 @@ struct FlatHashMapPolicy;
 //   `insert()`, provided that the map is provided a compatible heterogeneous
 //   hashing function and equality operator.
 // * Invalidates any references and pointers to elements within the table after
-//   `rehash()`.
+//   `rehash()` and when the table is moved.
 // * Contains a `capacity()` member function indicating the number of element
 //   slots (open, deleted, and empty) within the hash map.
 // * Returns `void` from the `erase(iterator)` overload.
@@ -579,9 +579,9 @@ struct FlatHashMapPolicy {
   }
 
   template <class Allocator>
-  static void transfer(Allocator* alloc, slot_type* new_slot,
+  static auto transfer(Allocator* alloc, slot_type* new_slot,
                        slot_type* old_slot) {
-    slot_policy::transfer(alloc, new_slot, old_slot);
+    return slot_policy::transfer(alloc, new_slot, old_slot);
   }
 
   template <class F, class... Args>
diff --git a/contrib/restricted/abseil-cpp/absl/container/flat_hash_set.h b/contrib/restricted/abseil-cpp/absl/container/flat_hash_set.h
index c789c7ef54..a94a82a0bf 100644
--- a/contrib/restricted/abseil-cpp/absl/container/flat_hash_set.h
+++ b/contrib/restricted/abseil-cpp/absl/container/flat_hash_set.h
@@ -60,7 +60,7 @@ struct FlatHashSetPolicy;
 //   that the set is provided a compatible heterogeneous hashing function and
 //   equality operator.
 // * Invalidates any references and pointers to elements within the table after
-//   `rehash()`.
+//   `rehash()` and when the table is moved.
 // * Contains a `capacity()` member function indicating the number of element
 //   slots (open, deleted, and empty) within the hash set.
 // * Returns `void` from the `erase(iterator)` overload.
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/common_policy_traits.h b/contrib/restricted/abseil-cpp/absl/container/internal/common_policy_traits.h
index 3558a5439b..57eac678fa 100644
--- a/contrib/restricted/abseil-cpp/absl/container/internal/common_policy_traits.h
+++ b/contrib/restricted/abseil-cpp/absl/container/internal/common_policy_traits.h
@@ -93,11 +93,13 @@ struct common_policy_traits {
   struct Rank0 : Rank1 {};
 
   // Use auto -> decltype as an enabler.
+  // P::transfer returns std::true_type if transfer uses memcpy (e.g. in
+  // node_slot_policy).
   template <class Alloc, class P = Policy>
   static auto transfer_impl(Alloc* alloc, slot_type* new_slot,
                             slot_type* old_slot, Rank0)
-      -> decltype((void)P::transfer(alloc, new_slot, old_slot)) {
-    P::transfer(alloc, new_slot, old_slot);
+      -> decltype(P::transfer(alloc, new_slot, old_slot)) {
+    return P::transfer(alloc, new_slot, old_slot);
   }
 #if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606
   // This overload returns true_type for the trait below.
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/container_memory.h b/contrib/restricted/abseil-cpp/absl/container/internal/container_memory.h
index f59ca4ee22..3262d4eb8d 100644
--- a/contrib/restricted/abseil-cpp/absl/container/internal/container_memory.h
+++ b/contrib/restricted/abseil-cpp/absl/container/internal/container_memory.h
@@ -122,10 +122,10 @@ auto TupleRefImpl(T&& t, absl::index_sequence<Is...>)
 // Returns a tuple of references to the elements of the input tuple. T must be a
 // tuple.
 template <class T>
-auto TupleRef(T&& t) -> decltype(
-    TupleRefImpl(std::forward<T>(t),
-                 absl::make_index_sequence<
-                     std::tuple_size<typename std::decay<T>::type>::value>())) {
+auto TupleRef(T&& t) -> decltype(TupleRefImpl(
+    std::forward<T>(t),
+    absl::make_index_sequence<
+        std::tuple_size<typename std::decay<T>::type>::value>())) {
   return TupleRefImpl(
       std::forward<T>(t),
       absl::make_index_sequence<
@@ -156,8 +156,8 @@ void ConstructFromTuple(Alloc* alloc, T* ptr, Tuple&& t) {
 // Constructs T using the args specified in the tuple and calls F with the
 // constructed value.
 template <class T, class Tuple, class F>
-decltype(std::declval<F>()(std::declval<T>())) WithConstructed(
-    Tuple&& t, F&& f) {
+decltype(std::declval<F>()(std::declval<T>())) WithConstructed(Tuple&& t,
+                                                               F&& f) {
   return memory_internal::WithConstructedImpl<T>(
       std::forward<Tuple>(t),
       absl::make_index_sequence<
@@ -423,16 +423,19 @@ struct map_slot_policy {
   }
 
   template <class Allocator>
-  static void transfer(Allocator* alloc, slot_type* new_slot,
+  static auto transfer(Allocator* alloc, slot_type* new_slot,
                        slot_type* old_slot) {
+    auto is_relocatable =
+        typename absl::is_trivially_relocatable<value_type>::type();
+
     emplace(new_slot);
 #if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606
-    if (absl::is_trivially_relocatable<value_type>()) {
+    if (is_relocatable) {
       // TODO(b/247130232,b/251814870): remove casts after fixing warnings.
       std::memcpy(static_cast<void*>(std::launder(&new_slot->value)),
                   static_cast<const void*>(&old_slot->value),
                   sizeof(value_type));
-      return;
+      return is_relocatable;
     }
 #endif
 
@@ -444,6 +447,7 @@ struct map_slot_policy {
                                                    std::move(old_slot->value));
     }
     destroy(alloc, old_slot);
+    return is_relocatable;
   }
 };
 
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/hashtablez_sampler.h b/contrib/restricted/abseil-cpp/absl/container/internal/hashtablez_sampler.h
index d8fd8f34f9..e41ee2d747 100644
--- a/contrib/restricted/abseil-cpp/absl/container/internal/hashtablez_sampler.h
+++ b/contrib/restricted/abseil-cpp/absl/container/internal/hashtablez_sampler.h
@@ -137,18 +137,7 @@ class HashtablezInfoHandle {
     UnsampleSlow(info_);
   }
 
-  HashtablezInfoHandle(const HashtablezInfoHandle&) = delete;
-  HashtablezInfoHandle& operator=(const HashtablezInfoHandle&) = delete;
-
-  HashtablezInfoHandle(HashtablezInfoHandle&& o) noexcept
-      : info_(absl::exchange(o.info_, nullptr)) {}
-  HashtablezInfoHandle& operator=(HashtablezInfoHandle&& o) noexcept {
-    if (ABSL_PREDICT_FALSE(info_ != nullptr)) {
-      UnsampleSlow(info_);
-    }
-    info_ = absl::exchange(o.info_, nullptr);
-    return *this;
-  }
+  inline bool IsSampled() const { return ABSL_PREDICT_FALSE(info_ != nullptr); }
 
   inline void RecordStorageChanged(size_t size, size_t capacity) {
     if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
@@ -198,6 +187,7 @@ class HashtablezInfoHandle {
   explicit HashtablezInfoHandle(std::nullptr_t) {}
 
   inline void Unregister() {}
+  inline bool IsSampled() const { return false; }
   inline void RecordStorageChanged(size_t /*size*/, size_t /*capacity*/) {}
   inline void RecordRehash(size_t /*total_probe_length*/) {}
   inline void RecordReservation(size_t /*target_capacity*/) {}
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/inlined_vector.h b/contrib/restricted/abseil-cpp/absl/container/internal/inlined_vector.h
index b2a602db7e..0eb9c34ddd 100644
--- a/contrib/restricted/abseil-cpp/absl/container/internal/inlined_vector.h
+++ b/contrib/restricted/abseil-cpp/absl/container/internal/inlined_vector.h
@@ -26,6 +26,7 @@
 #include <utility>
 
 #include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/macros.h"
 #include "absl/container/internal/compressed_tuple.h"
 #include "absl/memory/memory.h"
@@ -384,7 +385,17 @@ class Storage {
 
   bool GetIsAllocated() const { return GetSizeAndIsAllocated() & 1; }
 
-  Pointer<A> GetAllocatedData() { return data_.allocated.allocated_data; }
+  Pointer<A> GetAllocatedData() {
+    // GCC 12 has a false-positive -Wmaybe-uninitialized warning here.
+#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
+#endif
+    return data_.allocated.allocated_data;
+#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
+#pragma GCC diagnostic pop
+#endif
+  }
 
   ConstPointer<A> GetAllocatedData() const {
     return data_.allocated.allocated_data;
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/layout.h b/contrib/restricted/abseil-cpp/absl/container/internal/layout.h
deleted file mode 100644
index a59a243059..0000000000
--- a/contrib/restricted/abseil-cpp/absl/container/internal/layout.h
+++ /dev/null
@@ -1,743 +0,0 @@
-// Copyright 2018 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-//                           MOTIVATION AND TUTORIAL
-//
-// If you want to put in a single heap allocation N doubles followed by M ints,
-// it's easy if N and M are known at compile time.
-//
-//   struct S {
-//     double a[N];
-//     int b[M];
-//   };
-//
-//   S* p = new S;
-//
-// But what if N and M are known only in run time? Class template Layout to the
-// rescue! It's a portable generalization of the technique known as struct hack.
-//
-//   // This object will tell us everything we need to know about the memory
-//   // layout of double[N] followed by int[M]. It's structurally identical to
-//   // size_t[2] that stores N and M. It's very cheap to create.
-//   const Layout<double, int> layout(N, M);
-//
-//   // Allocate enough memory for both arrays. `AllocSize()` tells us how much
-//   // memory is needed. We are free to use any allocation function we want as
-//   // long as it returns aligned memory.
-//   std::unique_ptr<unsigned char[]> p(new unsigned char[layout.AllocSize()]);
-//
-//   // Obtain the pointer to the array of doubles.
-//   // Equivalent to `reinterpret_cast<double*>(p.get())`.
-//   //
-//   // We could have written layout.Pointer<0>(p) instead. If all the types are
-//   // unique you can use either form, but if some types are repeated you must
-//   // use the index form.
-//   double* a = layout.Pointer<double>(p.get());
-//
-//   // Obtain the pointer to the array of ints.
-//   // Equivalent to `reinterpret_cast<int*>(p.get() + N * 8)`.
-//   int* b = layout.Pointer<int>(p);
-//
-// If we are unable to specify sizes of all fields, we can pass as many sizes as
-// we can to `Partial()`. In return, it'll allow us to access the fields whose
-// locations and sizes can be computed from the provided information.
-// `Partial()` comes in handy when the array sizes are embedded into the
-// allocation.
-//
-//   // size_t[1] containing N, size_t[1] containing M, double[N], int[M].
-//   using L = Layout<size_t, size_t, double, int>;
-//
-//   unsigned char* Allocate(size_t n, size_t m) {
-//     const L layout(1, 1, n, m);
-//     unsigned char* p = new unsigned char[layout.AllocSize()];
-//     *layout.Pointer<0>(p) = n;
-//     *layout.Pointer<1>(p) = m;
-//     return p;
-//   }
-//
-//   void Use(unsigned char* p) {
-//     // First, extract N and M.
-//     // Specify that the first array has only one element. Using `prefix` we
-//     // can access the first two arrays but not more.
-//     constexpr auto prefix = L::Partial(1);
-//     size_t n = *prefix.Pointer<0>(p);
-//     size_t m = *prefix.Pointer<1>(p);
-//
-//     // Now we can get pointers to the payload.
-//     const L layout(1, 1, n, m);
-//     double* a = layout.Pointer<double>(p);
-//     int* b = layout.Pointer<int>(p);
-//   }
-//
-// The layout we used above combines fixed-size with dynamically-sized fields.
-// This is quite common. Layout is optimized for this use case and generates
-// optimal code. All computations that can be performed at compile time are
-// indeed performed at compile time.
-//
-// Efficiency tip: The order of fields matters. In `Layout<T1, ..., TN>` try to
-// ensure that `alignof(T1) >= ... >= alignof(TN)`. This way you'll have no
-// padding in between arrays.
-//
-// You can manually override the alignment of an array by wrapping the type in
-// `Aligned<T, N>`. `Layout<..., Aligned<T, N>, ...>` has exactly the same API
-// and behavior as `Layout<..., T, ...>` except that the first element of the
-// array of `T` is aligned to `N` (the rest of the elements follow without
-// padding). `N` cannot be less than `alignof(T)`.
-//
-// `AllocSize()` and `Pointer()` are the most basic methods for dealing with
-// memory layouts. Check out the reference or code below to discover more.
-//
-//                            EXAMPLE
-//
-//   // Immutable move-only string with sizeof equal to sizeof(void*). The
-//   // string size and the characters are kept in the same heap allocation.
-//   class CompactString {
-//    public:
-//     CompactString(const char* s = "") {
-//       const size_t size = strlen(s);
-//       // size_t[1] followed by char[size + 1].
-//       const L layout(1, size + 1);
-//       p_.reset(new unsigned char[layout.AllocSize()]);
-//       // If running under ASAN, mark the padding bytes, if any, to catch
-//       // memory errors.
-//       layout.PoisonPadding(p_.get());
-//       // Store the size in the allocation.
-//       *layout.Pointer<size_t>(p_.get()) = size;
-//       // Store the characters in the allocation.
-//       memcpy(layout.Pointer<char>(p_.get()), s, size + 1);
-//     }
-//
-//     size_t size() const {
-//       // Equivalent to reinterpret_cast<size_t&>(*p).
-//       return *L::Partial().Pointer<size_t>(p_.get());
-//     }
-//
-//     const char* c_str() const {
-//       // Equivalent to reinterpret_cast<char*>(p.get() + sizeof(size_t)).
-//       // The argument in Partial(1) specifies that we have size_t[1] in front
-//       // of the characters.
-//       return L::Partial(1).Pointer<char>(p_.get());
-//     }
-//
-//    private:
-//     // Our heap allocation contains a size_t followed by an array of chars.
-//     using L = Layout<size_t, char>;
-//     std::unique_ptr<unsigned char[]> p_;
-//   };
-//
-//   int main() {
-//     CompactString s = "hello";
-//     assert(s.size() == 5);
-//     assert(strcmp(s.c_str(), "hello") == 0);
-//   }
-//
-//                               DOCUMENTATION
-//
-// The interface exported by this file consists of:
-// - class `Layout<>` and its public members.
-// - The public members of class `internal_layout::LayoutImpl<>`. That class
-//   isn't intended to be used directly, and its name and template parameter
-//   list are internal implementation details, but the class itself provides
-//   most of the functionality in this file. See comments on its members for
-//   detailed documentation.
-//
-// `Layout<T1,... Tn>::Partial(count1,..., countm)` (where `m` <= `n`) returns a
-// `LayoutImpl<>` object. `Layout<T1,..., Tn> layout(count1,..., countn)`
-// creates a `Layout` object, which exposes the same functionality by inheriting
-// from `LayoutImpl<>`.
-
-#ifndef ABSL_CONTAINER_INTERNAL_LAYOUT_H_
-#define ABSL_CONTAINER_INTERNAL_LAYOUT_H_
-
-#include <assert.h>
-#include <stddef.h>
-#include <stdint.h>
-
-#include <ostream>
-#include <string>
-#include <tuple>
-#include <type_traits>
-#include <typeinfo>
-#include <utility>
-
-#include "absl/base/config.h"
-#include "absl/meta/type_traits.h"
-#include "absl/strings/str_cat.h"
-#include "absl/types/span.h"
-#include "absl/utility/utility.h"
-
-#ifdef ABSL_HAVE_ADDRESS_SANITIZER
-#include <sanitizer/asan_interface.h>
-#endif
-
-#if defined(__GXX_RTTI)
-#define ABSL_INTERNAL_HAS_CXA_DEMANGLE
-#endif
-
-#ifdef ABSL_INTERNAL_HAS_CXA_DEMANGLE
-#include <cxxabi.h>
-#endif
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace container_internal {
-
-// A type wrapper that instructs `Layout` to use the specific alignment for the
-// array. `Layout<..., Aligned<T, N>, ...>` has exactly the same API
-// and behavior as `Layout<..., T, ...>` except that the first element of the
-// array of `T` is aligned to `N` (the rest of the elements follow without
-// padding).
-//
-// Requires: `N >= alignof(T)` and `N` is a power of 2.
-template <class T, size_t N>
-struct Aligned;
-
-namespace internal_layout {
-
-template <class T>
-struct NotAligned {};
-
-template <class T, size_t N>
-struct NotAligned<const Aligned<T, N>> {
-  static_assert(sizeof(T) == 0, "Aligned<T, N> cannot be const-qualified");
-};
-
-template <size_t>
-using IntToSize = size_t;
-
-template <class>
-using TypeToSize = size_t;
-
-template <class T>
-struct Type : NotAligned<T> {
-  using type = T;
-};
-
-template <class T, size_t N>
-struct Type<Aligned<T, N>> {
-  using type = T;
-};
-
-template <class T>
-struct SizeOf : NotAligned<T>, std::integral_constant<size_t, sizeof(T)> {};
-
-template <class T, size_t N>
-struct SizeOf<Aligned<T, N>> : std::integral_constant<size_t, sizeof(T)> {};
-
-// Note: workaround for https://gcc.gnu.org/PR88115
-template <class T>
-struct AlignOf : NotAligned<T> {
-  static constexpr size_t value = alignof(T);
-};
-
-template <class T, size_t N>
-struct AlignOf<Aligned<T, N>> {
-  static_assert(N % alignof(T) == 0,
-                "Custom alignment can't be lower than the type's alignment");
-  static constexpr size_t value = N;
-};
-
-// Does `Ts...` contain `T`?
-template <class T, class... Ts>
-using Contains = absl::disjunction<std::is_same<T, Ts>...>;
-
-template <class From, class To>
-using CopyConst =
-    typename std::conditional<std::is_const<From>::value, const To, To>::type;
-
-// Note: We're not qualifying this with absl:: because it doesn't compile under
-// MSVC.
-template <class T>
-using SliceType = Span<T>;
-
-// This namespace contains no types. It prevents functions defined in it from
-// being found by ADL.
-namespace adl_barrier {
-
-template <class Needle, class... Ts>
-constexpr size_t Find(Needle, Needle, Ts...) {
-  static_assert(!Contains<Needle, Ts...>(), "Duplicate element type");
-  return 0;
-}
-
-template <class Needle, class T, class... Ts>
-constexpr size_t Find(Needle, T, Ts...) {
-  return adl_barrier::Find(Needle(), Ts()...) + 1;
-}
-
-constexpr bool IsPow2(size_t n) { return !(n & (n - 1)); }
-
-// Returns `q * m` for the smallest `q` such that `q * m >= n`.
-// Requires: `m` is a power of two. It's enforced by IsLegalElementType below.
-constexpr size_t Align(size_t n, size_t m) { return (n + m - 1) & ~(m - 1); }
-
-constexpr size_t Min(size_t a, size_t b) { return b < a ? b : a; }
-
-constexpr size_t Max(size_t a) { return a; }
-
-template <class... Ts>
-constexpr size_t Max(size_t a, size_t b, Ts... rest) {
-  return adl_barrier::Max(b < a ? a : b, rest...);
-}
-
-template <class T>
-std::string TypeName() {
-  std::string out;
-  int status = 0;
-  char* demangled = nullptr;
-#ifdef ABSL_INTERNAL_HAS_CXA_DEMANGLE
-  demangled = abi::__cxa_demangle(typeid(T).name(), nullptr, nullptr, &status);
-#endif
-  if (status == 0 && demangled != nullptr) {  // Demangling succeeded.
-    absl::StrAppend(&out, "<", demangled, ">");
-    free(demangled);
-  } else {
-#if defined(__GXX_RTTI) || defined(_CPPRTTI)
-    absl::StrAppend(&out, "<", typeid(T).name(), ">");
-#endif
-  }
-  return out;
-}
-
-}  // namespace adl_barrier
-
-template <bool C>
-using EnableIf = typename std::enable_if<C, int>::type;
-
-// Can `T` be a template argument of `Layout`?
-template <class T>
-using IsLegalElementType = std::integral_constant<
-    bool, !std::is_reference<T>::value && !std::is_volatile<T>::value &&
-              !std::is_reference<typename Type<T>::type>::value &&
-              !std::is_volatile<typename Type<T>::type>::value &&
-              adl_barrier::IsPow2(AlignOf<T>::value)>;
-
-template <class Elements, class SizeSeq, class OffsetSeq>
-class LayoutImpl;
-
-// Public base class of `Layout` and the result type of `Layout::Partial()`.
-//
-// `Elements...` contains all template arguments of `Layout` that created this
-// instance.
-//
-// `SizeSeq...` is `[0, NumSizes)` where `NumSizes` is the number of arguments
-// passed to `Layout::Partial()` or `Layout::Layout()`.
-//
-// `OffsetSeq...` is `[0, NumOffsets)` where `NumOffsets` is
-// `Min(sizeof...(Elements), NumSizes + 1)` (the number of arrays for which we
-// can compute offsets).
-template <class... Elements, size_t... SizeSeq, size_t... OffsetSeq>
-class LayoutImpl<std::tuple<Elements...>, absl::index_sequence<SizeSeq...>,
-                 absl::index_sequence<OffsetSeq...>> {
- private:
-  static_assert(sizeof...(Elements) > 0, "At least one field is required");
-  static_assert(absl::conjunction<IsLegalElementType<Elements>...>::value,
-                "Invalid element type (see IsLegalElementType)");
-
-  enum {
-    NumTypes = sizeof...(Elements),
-    NumSizes = sizeof...(SizeSeq),
-    NumOffsets = sizeof...(OffsetSeq),
-  };
-
-  // These are guaranteed by `Layout`.
-  static_assert(NumOffsets == adl_barrier::Min(NumTypes, NumSizes + 1),
-                "Internal error");
-  static_assert(NumTypes > 0, "Internal error");
-
-  // Returns the index of `T` in `Elements...`. Results in a compilation error
-  // if `Elements...` doesn't contain exactly one instance of `T`.
-  template <class T>
-  static constexpr size_t ElementIndex() {
-    static_assert(Contains<Type<T>, Type<typename Type<Elements>::type>...>(),
-                  "Type not found");
-    return adl_barrier::Find(Type<T>(),
-                             Type<typename Type<Elements>::type>()...);
-  }
-
-  template <size_t N>
-  using ElementAlignment =
-      AlignOf<typename std::tuple_element<N, std::tuple<Elements...>>::type>;
-
- public:
-  // Element types of all arrays packed in a tuple.
-  using ElementTypes = std::tuple<typename Type<Elements>::type...>;
-
-  // Element type of the Nth array.
-  template <size_t N>
-  using ElementType = typename std::tuple_element<N, ElementTypes>::type;
-
-  constexpr explicit LayoutImpl(IntToSize<SizeSeq>... sizes)
-      : size_{sizes...} {}
-
-  // Alignment of the layout, equal to the strictest alignment of all elements.
-  // All pointers passed to the methods of layout must be aligned to this value.
-  static constexpr size_t Alignment() {
-    return adl_barrier::Max(AlignOf<Elements>::value...);
-  }
-
-  // Offset in bytes of the Nth array.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   assert(x.Offset<0>() == 0);   // The ints starts from 0.
-  //   assert(x.Offset<1>() == 16);  // The doubles starts from 16.
-  //
-  // Requires: `N <= NumSizes && N < sizeof...(Ts)`.
-  template <size_t N, EnableIf<N == 0> = 0>
-  constexpr size_t Offset() const {
-    return 0;
-  }
-
-  template <size_t N, EnableIf<N != 0> = 0>
-  constexpr size_t Offset() const {
-    static_assert(N < NumOffsets, "Index out of bounds");
-    return adl_barrier::Align(
-        Offset<N - 1>() + SizeOf<ElementType<N - 1>>::value * size_[N - 1],
-        ElementAlignment<N>::value);
-  }
-
-  // Offset in bytes of the array with the specified element type. There must
-  // be exactly one such array and its zero-based index must be at most
-  // `NumSizes`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   assert(x.Offset<int>() == 0);      // The ints starts from 0.
-  //   assert(x.Offset<double>() == 16);  // The doubles starts from 16.
-  template <class T>
-  constexpr size_t Offset() const {
-    return Offset<ElementIndex<T>()>();
-  }
-
-  // Offsets in bytes of all arrays for which the offsets are known.
-  constexpr std::array<size_t, NumOffsets> Offsets() const {
-    return {{Offset<OffsetSeq>()...}};
-  }
-
-  // The number of elements in the Nth array. This is the Nth argument of
-  // `Layout::Partial()` or `Layout::Layout()` (zero-based).
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   assert(x.Size<0>() == 3);
-  //   assert(x.Size<1>() == 4);
-  //
-  // Requires: `N < NumSizes`.
-  template <size_t N>
-  constexpr size_t Size() const {
-    static_assert(N < NumSizes, "Index out of bounds");
-    return size_[N];
-  }
-
-  // The number of elements in the array with the specified element type.
-  // There must be exactly one such array and its zero-based index must be
-  // at most `NumSizes`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   assert(x.Size<int>() == 3);
-  //   assert(x.Size<double>() == 4);
-  template <class T>
-  constexpr size_t Size() const {
-    return Size<ElementIndex<T>()>();
-  }
-
-  // The number of elements of all arrays for which they are known.
-  constexpr std::array<size_t, NumSizes> Sizes() const {
-    return {{Size<SizeSeq>()...}};
-  }
-
-  // Pointer to the beginning of the Nth array.
-  //
-  // `Char` must be `[const] [signed|unsigned] char`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   unsigned char* p = new unsigned char[x.AllocSize()];
-  //   int* ints = x.Pointer<0>(p);
-  //   double* doubles = x.Pointer<1>(p);
-  //
-  // Requires: `N <= NumSizes && N < sizeof...(Ts)`.
-  // Requires: `p` is aligned to `Alignment()`.
-  template <size_t N, class Char>
-  CopyConst<Char, ElementType<N>>* Pointer(Char* p) const {
-    using C = typename std::remove_const<Char>::type;
-    static_assert(
-        std::is_same<C, char>() || std::is_same<C, unsigned char>() ||
-            std::is_same<C, signed char>(),
-        "The argument must be a pointer to [const] [signed|unsigned] char");
-    constexpr size_t alignment = Alignment();
-    (void)alignment;
-    assert(reinterpret_cast<uintptr_t>(p) % alignment == 0);
-    return reinterpret_cast<CopyConst<Char, ElementType<N>>*>(p + Offset<N>());
-  }
-
-  // Pointer to the beginning of the array with the specified element type.
-  // There must be exactly one such array and its zero-based index must be at
-  // most `NumSizes`.
-  //
-  // `Char` must be `[const] [signed|unsigned] char`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   unsigned char* p = new unsigned char[x.AllocSize()];
-  //   int* ints = x.Pointer<int>(p);
-  //   double* doubles = x.Pointer<double>(p);
-  //
-  // Requires: `p` is aligned to `Alignment()`.
-  template <class T, class Char>
-  CopyConst<Char, T>* Pointer(Char* p) const {
-    return Pointer<ElementIndex<T>()>(p);
-  }
-
-  // Pointers to all arrays for which pointers are known.
-  //
-  // `Char` must be `[const] [signed|unsigned] char`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   unsigned char* p = new unsigned char[x.AllocSize()];
-  //
-  //   int* ints;
-  //   double* doubles;
-  //   std::tie(ints, doubles) = x.Pointers(p);
-  //
-  // Requires: `p` is aligned to `Alignment()`.
-  //
-  // Note: We're not using ElementType alias here because it does not compile
-  // under MSVC.
-  template <class Char>
-  std::tuple<CopyConst<
-      Char, typename std::tuple_element<OffsetSeq, ElementTypes>::type>*...>
-  Pointers(Char* p) const {
-    return std::tuple<CopyConst<Char, ElementType<OffsetSeq>>*...>(
-        Pointer<OffsetSeq>(p)...);
-  }
-
-  // The Nth array.
-  //
-  // `Char` must be `[const] [signed|unsigned] char`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   unsigned char* p = new unsigned char[x.AllocSize()];
-  //   Span<int> ints = x.Slice<0>(p);
-  //   Span<double> doubles = x.Slice<1>(p);
-  //
-  // Requires: `N < NumSizes`.
-  // Requires: `p` is aligned to `Alignment()`.
-  template <size_t N, class Char>
-  SliceType<CopyConst<Char, ElementType<N>>> Slice(Char* p) const {
-    return SliceType<CopyConst<Char, ElementType<N>>>(Pointer<N>(p), Size<N>());
-  }
-
-  // The array with the specified element type. There must be exactly one
-  // such array and its zero-based index must be less than `NumSizes`.
-  //
-  // `Char` must be `[const] [signed|unsigned] char`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   unsigned char* p = new unsigned char[x.AllocSize()];
-  //   Span<int> ints = x.Slice<int>(p);
-  //   Span<double> doubles = x.Slice<double>(p);
-  //
-  // Requires: `p` is aligned to `Alignment()`.
-  template <class T, class Char>
-  SliceType<CopyConst<Char, T>> Slice(Char* p) const {
-    return Slice<ElementIndex<T>()>(p);
-  }
-
-  // All arrays with known sizes.
-  //
-  // `Char` must be `[const] [signed|unsigned] char`.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   unsigned char* p = new unsigned char[x.AllocSize()];
-  //
-  //   Span<int> ints;
-  //   Span<double> doubles;
-  //   std::tie(ints, doubles) = x.Slices(p);
-  //
-  // Requires: `p` is aligned to `Alignment()`.
-  //
-  // Note: We're not using ElementType alias here because it does not compile
-  // under MSVC.
-  template <class Char>
-  std::tuple<SliceType<CopyConst<
-      Char, typename std::tuple_element<SizeSeq, ElementTypes>::type>>...>
-  Slices(Char* p) const {
-    // Workaround for https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63875 (fixed
-    // in 6.1).
-    (void)p;
-    return std::tuple<SliceType<CopyConst<Char, ElementType<SizeSeq>>>...>(
-        Slice<SizeSeq>(p)...);
-  }
-
-  // The size of the allocation that fits all arrays.
-  //
-  //   // int[3], 4 bytes of padding, double[4].
-  //   Layout<int, double> x(3, 4);
-  //   unsigned char* p = new unsigned char[x.AllocSize()];  // 48 bytes
-  //
-  // Requires: `NumSizes == sizeof...(Ts)`.
-  constexpr size_t AllocSize() const {
-    static_assert(NumTypes == NumSizes, "You must specify sizes of all fields");
-    return Offset<NumTypes - 1>() +
-        SizeOf<ElementType<NumTypes - 1>>::value * size_[NumTypes - 1];
-  }
-
-  // If built with --config=asan, poisons padding bytes (if any) in the
-  // allocation. The pointer must point to a memory block at least
-  // `AllocSize()` bytes in length.
-  //
-  // `Char` must be `[const] [signed|unsigned] char`.
-  //
-  // Requires: `p` is aligned to `Alignment()`.
-  template <class Char, size_t N = NumOffsets - 1, EnableIf<N == 0> = 0>
-  void PoisonPadding(const Char* p) const {
-    Pointer<0>(p);  // verify the requirements on `Char` and `p`
-  }
-
-  template <class Char, size_t N = NumOffsets - 1, EnableIf<N != 0> = 0>
-  void PoisonPadding(const Char* p) const {
-    static_assert(N < NumOffsets, "Index out of bounds");
-    (void)p;
-#ifdef ABSL_HAVE_ADDRESS_SANITIZER
-    PoisonPadding<Char, N - 1>(p);
-    // The `if` is an optimization. It doesn't affect the observable behaviour.
-    if (ElementAlignment<N - 1>::value % ElementAlignment<N>::value) {
-      size_t start =
-          Offset<N - 1>() + SizeOf<ElementType<N - 1>>::value * size_[N - 1];
-      ASAN_POISON_MEMORY_REGION(p + start, Offset<N>() - start);
-    }
-#endif
-  }
-
-  // Human-readable description of the memory layout. Useful for debugging.
-  // Slow.
-  //
-  //   // char[5], 3 bytes of padding, int[3], 4 bytes of padding, followed
-  //   // by an unknown number of doubles.
-  //   auto x = Layout<char, int, double>::Partial(5, 3);
-  //   assert(x.DebugString() ==
-  //          "@0<char>(1)[5]; @8<int>(4)[3]; @24<double>(8)");
-  //
-  // Each field is in the following format: @offset<type>(sizeof)[size] (<type>
-  // may be missing depending on the target platform). For example,
-  // @8<int>(4)[3] means that at offset 8 we have an array of ints, where each
-  // int is 4 bytes, and we have 3 of those ints. The size of the last field may
-  // be missing (as in the example above). Only fields with known offsets are
-  // described. Type names may differ across platforms: one compiler might
-  // produce "unsigned*" where another produces "unsigned int *".
-  std::string DebugString() const {
-    const auto offsets = Offsets();
-    const size_t sizes[] = {SizeOf<ElementType<OffsetSeq>>::value...};
-    const std::string types[] = {
-        adl_barrier::TypeName<ElementType<OffsetSeq>>()...};
-    std::string res = absl::StrCat("@0", types[0], "(", sizes[0], ")");
-    for (size_t i = 0; i != NumOffsets - 1; ++i) {
-      absl::StrAppend(&res, "[", size_[i], "]; @", offsets[i + 1], types[i + 1],
-                      "(", sizes[i + 1], ")");
-    }
-    // NumSizes is a constant that may be zero. Some compilers cannot see that
-    // inside the if statement "size_[NumSizes - 1]" must be valid.
-    int last = static_cast<int>(NumSizes) - 1;
-    if (NumTypes == NumSizes && last >= 0) {
-      absl::StrAppend(&res, "[", size_[last], "]");
-    }
-    return res;
-  }
-
- private:
-  // Arguments of `Layout::Partial()` or `Layout::Layout()`.
-  size_t size_[NumSizes > 0 ? NumSizes : 1];
-};
-
-template <size_t NumSizes, class... Ts>
-using LayoutType = LayoutImpl<
-    std::tuple<Ts...>, absl::make_index_sequence<NumSizes>,
-    absl::make_index_sequence<adl_barrier::Min(sizeof...(Ts), NumSizes + 1)>>;
-
-}  // namespace internal_layout
-
-// Descriptor of arrays of various types and sizes laid out in memory one after
-// another. See the top of the file for documentation.
-//
-// Check out the public API of internal_layout::LayoutImpl above. The type is
-// internal to the library but its methods are public, and they are inherited
-// by `Layout`.
-template <class... Ts>
-class Layout : public internal_layout::LayoutType<sizeof...(Ts), Ts...> {
- public:
-  static_assert(sizeof...(Ts) > 0, "At least one field is required");
-  static_assert(
-      absl::conjunction<internal_layout::IsLegalElementType<Ts>...>::value,
-      "Invalid element type (see IsLegalElementType)");
-
-  // The result type of `Partial()` with `NumSizes` arguments.
-  template <size_t NumSizes>
-  using PartialType = internal_layout::LayoutType<NumSizes, Ts...>;
-
-  // `Layout` knows the element types of the arrays we want to lay out in
-  // memory but not the number of elements in each array.
-  // `Partial(size1, ..., sizeN)` allows us to specify the latter. The
-  // resulting immutable object can be used to obtain pointers to the
-  // individual arrays.
-  //
-  // It's allowed to pass fewer array sizes than the number of arrays. E.g.,
-  // if all you need is to the offset of the second array, you only need to
-  // pass one argument -- the number of elements in the first array.
-  //
-  //   // int[3] followed by 4 bytes of padding and an unknown number of
-  //   // doubles.
-  //   auto x = Layout<int, double>::Partial(3);
-  //   // doubles start at byte 16.
-  //   assert(x.Offset<1>() == 16);
-  //
-  // If you know the number of elements in all arrays, you can still call
-  // `Partial()` but it's more convenient to use the constructor of `Layout`.
-  //
-  //   Layout<int, double> x(3, 5);
-  //
-  // Note: The sizes of the arrays must be specified in number of elements,
-  // not in bytes.
-  //
-  // Requires: `sizeof...(Sizes) <= sizeof...(Ts)`.
-  // Requires: all arguments are convertible to `size_t`.
-  template <class... Sizes>
-  static constexpr PartialType<sizeof...(Sizes)> Partial(Sizes&&... sizes) {
-    static_assert(sizeof...(Sizes) <= sizeof...(Ts), "");
-    return PartialType<sizeof...(Sizes)>(absl::forward<Sizes>(sizes)...);
-  }
-
-  // Creates a layout with the sizes of all arrays specified. If you know
-  // only the sizes of the first N arrays (where N can be zero), you can use
-  // `Partial()` defined above. The constructor is essentially equivalent to
-  // calling `Partial()` and passing in all array sizes; the constructor is
-  // provided as a convenient abbreviation.
-  //
-  // Note: The sizes of the arrays must be specified in number of elements,
-  // not in bytes.
-  constexpr explicit Layout(internal_layout::TypeToSize<Ts>... sizes)
-      : internal_layout::LayoutType<sizeof...(Ts), Ts...>(sizes...) {}
-};
-
-}  // namespace container_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_CONTAINER_INTERNAL_LAYOUT_H_
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_map.h b/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_map.h
index 2d5a8710ad..97182bc7bd 100644
--- a/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_map.h
+++ b/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_map.h
@@ -19,6 +19,8 @@
 #include <type_traits>
 #include <utility>
 
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/throw_delegate.h"
 #include "absl/container/internal/container_memory.h"
 #include "absl/container/internal/raw_hash_set.h"  // IWYU pragma: export
@@ -175,13 +177,20 @@ class raw_hash_map : public raw_hash_set<Policy, Hash, Eq, Alloc> {
   template <class K = key_type, class P = Policy, K* = nullptr>
   MappedReference<P> operator[](key_arg<K>&& key)
       ABSL_ATTRIBUTE_LIFETIME_BOUND {
-    return Policy::value(&*try_emplace(std::forward<K>(key)).first);
+    // It is safe to use unchecked_deref here because try_emplace
+    // will always return an iterator pointing to a valid item in the table,
+    // since it inserts if nothing is found for the given key.
+    return Policy::value(
+        &this->unchecked_deref(try_emplace(std::forward<K>(key)).first));
   }
 
   template <class K = key_type, class P = Policy>
   MappedReference<P> operator[](const key_arg<K>& key)
       ABSL_ATTRIBUTE_LIFETIME_BOUND {
-    return Policy::value(&*try_emplace(key).first);
+    // It is safe to use unchecked_deref here because try_emplace
+    // will always return an iterator pointing to a valid item in the table,
+    // since it inserts if nothing is found for the given key.
+    return Policy::value(&this->unchecked_deref(try_emplace(key).first));
   }
 
  private:
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.cc b/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.cc
index 2ff95b6182..9f8ea51987 100644
--- a/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.cc
+++ b/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.cc
@@ -17,11 +17,13 @@
 #include <atomic>
 #include <cassert>
 #include <cstddef>
+#include <cstdint>
 #include <cstring>
 
 #include "absl/base/attributes.h"
 #include "absl/base/config.h"
 #include "absl/base/dynamic_annotations.h"
+#include "absl/container/internal/container_memory.h"
 #include "absl/hash/hash.h"
 
 namespace absl {
@@ -67,6 +69,16 @@ inline size_t RandomSeed() {
   return value ^ static_cast<size_t>(reinterpret_cast<uintptr_t>(&counter));
 }
 
+bool ShouldRehashForBugDetection(const ctrl_t* ctrl, size_t capacity) {
+  // Note: we can't use the abseil-random library because abseil-random
+  // depends on swisstable. We want to return true with probability
+  // `min(1, RehashProbabilityConstant() / capacity())`. In order to do this,
+  // we probe based on a random hash and see if the offset is less than
+  // RehashProbabilityConstant().
+  return probe(ctrl, capacity, absl::HashOf(RandomSeed())).offset() <
+         RehashProbabilityConstant();
+}
+
 }  // namespace
 
 GenerationType* EmptyGeneration() {
@@ -84,13 +96,12 @@ bool CommonFieldsGenerationInfoEnabled::
                                               size_t capacity) const {
   if (reserved_growth_ == kReservedGrowthJustRanOut) return true;
   if (reserved_growth_ > 0) return false;
-  // Note: we can't use the abseil-random library because abseil-random
-  // depends on swisstable. We want to return true with probability
-  // `min(1, RehashProbabilityConstant() / capacity())`. In order to do this,
-  // we probe based on a random hash and see if the offset is less than
-  // RehashProbabilityConstant().
-  return probe(ctrl, capacity, absl::HashOf(RandomSeed())).offset() <
-         RehashProbabilityConstant();
+  return ShouldRehashForBugDetection(ctrl, capacity);
+}
+
+bool CommonFieldsGenerationInfoEnabled::should_rehash_for_bug_detection_on_move(
+    const ctrl_t* ctrl, size_t capacity) const {
+  return ShouldRehashForBugDetection(ctrl, capacity);
 }
 
 bool ShouldInsertBackwards(size_t hash, const ctrl_t* ctrl) {
@@ -117,14 +128,6 @@ FindInfo find_first_non_full_outofline(const CommonFields& common,
   return find_first_non_full(common, hash);
 }
 
-// Returns the address of the ith slot in slots where each slot occupies
-// slot_size.
-static inline void* SlotAddress(void* slot_array, size_t slot,
-                                size_t slot_size) {
-  return reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(slot_array) +
-                                 (slot * slot_size));
-}
-
 // Returns the address of the slot just after slot assuming each slot has the
 // specified size.
 static inline void* NextSlot(void* slot, size_t slot_size) {
@@ -218,26 +221,35 @@ void DropDeletesWithoutResize(CommonFields& common,
   common.infoz().RecordRehash(total_probe_length);
 }
 
-void EraseMetaOnly(CommonFields& c, ctrl_t* it, size_t slot_size) {
-  assert(IsFull(*it) && "erasing a dangling iterator");
-  c.set_size(c.size() - 1);
-  const auto index = static_cast<size_t>(it - c.control());
+static bool WasNeverFull(CommonFields& c, size_t index) {
+  if (is_single_group(c.capacity())) {
+    return true;
+  }
   const size_t index_before = (index - Group::kWidth) & c.capacity();
-  const auto empty_after = Group(it).MaskEmpty();
+  const auto empty_after = Group(c.control() + index).MaskEmpty();
   const auto empty_before = Group(c.control() + index_before).MaskEmpty();
 
   // We count how many consecutive non empties we have to the right and to the
   // left of `it`. If the sum is >= kWidth then there is at least one probe
   // window that might have seen a full group.
-  bool was_never_full = empty_before && empty_after &&
-                        static_cast<size_t>(empty_after.TrailingZeros()) +
-                                empty_before.LeadingZeros() <
-                            Group::kWidth;
-
-  SetCtrl(c, index, was_never_full ? ctrl_t::kEmpty : ctrl_t::kDeleted,
-          slot_size);
-  c.set_growth_left(c.growth_left() + (was_never_full ? 1 : 0));
+  return empty_before && empty_after &&
+         static_cast<size_t>(empty_after.TrailingZeros()) +
+                 empty_before.LeadingZeros() <
+             Group::kWidth;
+}
+
+void EraseMetaOnly(CommonFields& c, size_t index, size_t slot_size) {
+  assert(IsFull(c.control()[index]) && "erasing a dangling iterator");
+  c.decrement_size();
   c.infoz().RecordErase();
+
+  if (WasNeverFull(c, index)) {
+    SetCtrl(c, index, ctrl_t::kEmpty, slot_size);
+    c.set_growth_left(c.growth_left() + 1);
+    return;
+  }
+
+  SetCtrl(c, index, ctrl_t::kDeleted, slot_size);
 }
 
 void ClearBackingArray(CommonFields& c, const PolicyFunctions& policy,
@@ -245,19 +257,124 @@ void ClearBackingArray(CommonFields& c, const PolicyFunctions& policy,
   c.set_size(0);
   if (reuse) {
     ResetCtrl(c, policy.slot_size);
+    ResetGrowthLeft(c);
     c.infoz().RecordStorageChanged(0, c.capacity());
   } else {
+    // We need to record infoz before calling dealloc, which will unregister
+    // infoz.
+    c.infoz().RecordClearedReservation();
+    c.infoz().RecordStorageChanged(0, 0);
     (*policy.dealloc)(c, policy);
     c.set_control(EmptyGroup());
     c.set_generation_ptr(EmptyGeneration());
     c.set_slots(nullptr);
     c.set_capacity(0);
-    c.infoz().RecordClearedReservation();
-    assert(c.size() == 0);
-    c.infoz().RecordStorageChanged(0, 0);
   }
 }
 
+void HashSetResizeHelper::GrowIntoSingleGroupShuffleControlBytes(
+    ctrl_t* new_ctrl, size_t new_capacity) const {
+  assert(is_single_group(new_capacity));
+  constexpr size_t kHalfWidth = Group::kWidth / 2;
+  assert(old_capacity_ < kHalfWidth);
+
+  const size_t half_old_capacity = old_capacity_ / 2;
+
+  // NOTE: operations are done with compile time known size = kHalfWidth.
+  // Compiler optimizes that into single ASM operation.
+
+  // Copy second half of bytes to the beginning.
+  // We potentially copy more bytes in order to have compile time known size.
+  // Mirrored bytes from the old_ctrl_ will also be copied.
+  // In case of old_capacity_ == 3, we will copy 1st element twice.
+  // Examples:
+  // old_ctrl = 0S0EEEEEEE...
+  // new_ctrl = S0EEEEEEEE...
+  //
+  // old_ctrl = 01S01EEEEE...
+  // new_ctrl = 1S01EEEEEE...
+  //
+  // old_ctrl = 0123456S0123456EE...
+  // new_ctrl = 456S0123?????????...
+  std::memcpy(new_ctrl, old_ctrl_ + half_old_capacity + 1, kHalfWidth);
+  // Clean up copied kSentinel from old_ctrl.
+  new_ctrl[half_old_capacity] = ctrl_t::kEmpty;
+
+  // Clean up damaged or uninitialized bytes.
+
+  // Clean bytes after the intended size of the copy.
+  // Example:
+  // new_ctrl = 1E01EEEEEEE????
+  // *new_ctrl= 1E0EEEEEEEE????
+  // position      /
+  std::memset(new_ctrl + old_capacity_ + 1, static_cast<int8_t>(ctrl_t::kEmpty),
+              kHalfWidth);
+  // Clean non-mirrored bytes that are not initialized.
+  // For small old_capacity that may be inside of mirrored bytes zone.
+  // Examples:
+  // new_ctrl = 1E0EEEEEEEE??????????....
+  // *new_ctrl= 1E0EEEEEEEEEEEEE?????....
+  // position           /
+  //
+  // new_ctrl = 456E0123???????????...
+  // *new_ctrl= 456E0123EEEEEEEE???...
+  // position           /
+  std::memset(new_ctrl + kHalfWidth, static_cast<int8_t>(ctrl_t::kEmpty),
+              kHalfWidth);
+  // Clean last mirrored bytes that are not initialized
+  // and will not be overwritten by mirroring.
+  // Examples:
+  // new_ctrl = 1E0EEEEEEEEEEEEE????????
+  // *new_ctrl= 1E0EEEEEEEEEEEEEEEEEEEEE
+  // position           S       /
+  //
+  // new_ctrl = 456E0123EEEEEEEE???????????????
+  // *new_ctrl= 456E0123EEEEEEEE???????EEEEEEEE
+  // position                  S       /
+  std::memset(new_ctrl + new_capacity + kHalfWidth,
+              static_cast<int8_t>(ctrl_t::kEmpty), kHalfWidth);
+
+  // Create mirrored bytes. old_capacity_ < kHalfWidth
+  // Example:
+  // new_ctrl = 456E0123EEEEEEEE???????EEEEEEEE
+  // *new_ctrl= 456E0123EEEEEEEE456E0123EEEEEEE
+  // position                  S/
+  ctrl_t g[kHalfWidth];
+  std::memcpy(g, new_ctrl, kHalfWidth);
+  std::memcpy(new_ctrl + new_capacity + 1, g, kHalfWidth);
+
+  // Finally set sentinel to its place.
+  new_ctrl[new_capacity] = ctrl_t::kSentinel;
+}
+
+void HashSetResizeHelper::GrowIntoSingleGroupShuffleTransferableSlots(
+    void* old_slots, void* new_slots, size_t slot_size) const {
+  assert(old_capacity_ > 0);
+  const size_t half_old_capacity = old_capacity_ / 2;
+
+  SanitizerUnpoisonMemoryRegion(old_slots, slot_size * old_capacity_);
+  std::memcpy(new_slots,
+              SlotAddress(old_slots, half_old_capacity + 1, slot_size),
+              slot_size * half_old_capacity);
+  std::memcpy(SlotAddress(new_slots, half_old_capacity + 1, slot_size),
+              old_slots, slot_size * (half_old_capacity + 1));
+}
+
+void HashSetResizeHelper::GrowSizeIntoSingleGroupTransferable(
+    CommonFields& c, void* old_slots, size_t slot_size) {
+  assert(old_capacity_ < Group::kWidth / 2);
+  assert(is_single_group(c.capacity()));
+  assert(IsGrowingIntoSingleGroupApplicable(old_capacity_, c.capacity()));
+
+  GrowIntoSingleGroupShuffleControlBytes(c.control(), c.capacity());
+  GrowIntoSingleGroupShuffleTransferableSlots(old_slots, c.slot_array(),
+                                              slot_size);
+
+  // We poison since GrowIntoSingleGroupShuffleTransferableSlots
+  // may leave empty slots unpoisoned.
+  PoisonSingleGroupEmptySlots(c, slot_size);
+}
+
 }  // namespace container_internal
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.h b/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.h
index 5f89d8efee..3518bc3404 100644
--- a/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.h
+++ b/contrib/restricted/abseil-cpp/absl/container/internal/raw_hash_set.h
@@ -62,6 +62,9 @@
 // pseudo-struct:
 //
 //   struct BackingArray {
+//     // Sampling handler. This field isn't present when the sampling is
+//     // disabled or this allocation hasn't been selected for sampling.
+//     HashtablezInfoHandle infoz_;
 //     // The number of elements we can insert before growing the capacity.
 //     size_t growth_left;
 //     // Control bytes for the "real" slots.
@@ -175,25 +178,29 @@
 #define ABSL_CONTAINER_INTERNAL_RAW_HASH_SET_H_
 
 #include <algorithm>
+#include <cassert>
 #include <cmath>
 #include <cstddef>
 #include <cstdint>
 #include <cstring>
+#include <initializer_list>
 #include <iterator>
 #include <limits>
 #include <memory>
-#include <string>
 #include <tuple>
 #include <type_traits>
 #include <utility>
 
+#include "absl/base/attributes.h"
 #include "absl/base/config.h"
 #include "absl/base/internal/endian.h"
 #include "absl/base/internal/raw_logging.h"
+#include "absl/base/macros.h"
 #include "absl/base/optimization.h"
+#include "absl/base/options.h"
 #include "absl/base/port.h"
 #include "absl/base/prefetch.h"
-#include "absl/container/internal/common.h"
+#include "absl/container/internal/common.h"  // IWYU pragma: export // for node_handle
 #include "absl/container/internal/compressed_tuple.h"
 #include "absl/container/internal/container_memory.h"
 #include "absl/container/internal/hash_policy_traits.h"
@@ -227,6 +234,7 @@ namespace container_internal {
 #ifdef ABSL_SWISSTABLE_ENABLE_GENERATIONS
 #error ABSL_SWISSTABLE_ENABLE_GENERATIONS cannot be directly set
 #elif defined(ABSL_HAVE_ADDRESS_SANITIZER) || \
+    defined(ABSL_HAVE_HWADDRESS_SANITIZER) || \
     defined(ABSL_HAVE_MEMORY_SANITIZER)
 // When compiled in sanitizer mode, we add generation integers to the backing
 // array and iterators. In the backing array, we store the generation between
@@ -262,8 +270,21 @@ void SwapAlloc(AllocType& lhs, AllocType& rhs,
   swap(lhs, rhs);
 }
 template <typename AllocType>
-void SwapAlloc(AllocType& /*lhs*/, AllocType& /*rhs*/,
-               std::false_type /* propagate_on_container_swap */) {}
+void SwapAlloc(AllocType& lhs, AllocType& rhs,
+               std::false_type /* propagate_on_container_swap */) {
+  (void)lhs;
+  (void)rhs;
+  assert(lhs == rhs &&
+         "It's UB to call swap with unequal non-propagating allocators.");
+}
+
+template <typename AllocType>
+void CopyAlloc(AllocType& lhs, AllocType& rhs,
+               std::true_type /* propagate_alloc */) {
+  lhs = rhs;
+}
+template <typename AllocType>
+void CopyAlloc(AllocType&, AllocType&, std::false_type /* propagate_alloc */) {}
 
 // The state for a probe sequence.
 //
@@ -361,7 +382,7 @@ uint32_t TrailingZeros(T x) {
 // width of an abstract bit in the representation.
 // This mask provides operations for any number of real bits set in an abstract
 // bit. To add iteration on top of that, implementation must guarantee no more
-// than one real bit is set in an abstract bit.
+// than the most significant real bit is set in a set abstract bit.
 template <class T, int SignificantBits, int Shift = 0>
 class NonIterableBitMask {
  public:
@@ -388,7 +409,9 @@ class NonIterableBitMask {
   uint32_t LeadingZeros() const {
     constexpr int total_significant_bits = SignificantBits << Shift;
     constexpr int extra_bits = sizeof(T) * 8 - total_significant_bits;
-    return static_cast<uint32_t>(countl_zero(mask_ << extra_bits)) >> Shift;
+    return static_cast<uint32_t>(
+               countl_zero(static_cast<T>(mask_ << extra_bits))) >>
+           Shift;
   }
 
   T mask_;
@@ -418,6 +441,10 @@ class BitMask : public NonIterableBitMask<T, SignificantBits, Shift> {
   using const_iterator = BitMask;
 
   BitMask& operator++() {
+    if (Shift == 3) {
+      constexpr uint64_t msbs = 0x8080808080808080ULL;
+      this->mask_ &= msbs;
+    }
     this->mask_ &= (this->mask_ - 1);
     return *this;
   }
@@ -590,29 +617,39 @@ struct GroupSse2Impl {
   }
 
   // Returns a bitmask representing the positions of slots that match hash.
-  BitMask<uint32_t, kWidth> Match(h2_t hash) const {
+  BitMask<uint16_t, kWidth> Match(h2_t hash) const {
     auto match = _mm_set1_epi8(static_cast<char>(hash));
-    return BitMask<uint32_t, kWidth>(
-        static_cast<uint32_t>(_mm_movemask_epi8(_mm_cmpeq_epi8(match, ctrl))));
+    BitMask<uint16_t, kWidth> result = BitMask<uint16_t, kWidth>(0);
+    result = BitMask<uint16_t, kWidth>(
+        static_cast<uint16_t>(_mm_movemask_epi8(_mm_cmpeq_epi8(match, ctrl))));
+    return result;
   }
 
   // Returns a bitmask representing the positions of empty slots.
-  NonIterableBitMask<uint32_t, kWidth> MaskEmpty() const {
+  NonIterableBitMask<uint16_t, kWidth> MaskEmpty() const {
 #ifdef ABSL_INTERNAL_HAVE_SSSE3
     // This only works because ctrl_t::kEmpty is -128.
-    return NonIterableBitMask<uint32_t, kWidth>(
-        static_cast<uint32_t>(_mm_movemask_epi8(_mm_sign_epi8(ctrl, ctrl))));
+    return NonIterableBitMask<uint16_t, kWidth>(
+        static_cast<uint16_t>(_mm_movemask_epi8(_mm_sign_epi8(ctrl, ctrl))));
 #else
     auto match = _mm_set1_epi8(static_cast<char>(ctrl_t::kEmpty));
-    return NonIterableBitMask<uint32_t, kWidth>(
-        static_cast<uint32_t>(_mm_movemask_epi8(_mm_cmpeq_epi8(match, ctrl))));
+    return NonIterableBitMask<uint16_t, kWidth>(
+        static_cast<uint16_t>(_mm_movemask_epi8(_mm_cmpeq_epi8(match, ctrl))));
 #endif
   }
 
+  // Returns a bitmask representing the positions of full slots.
+  // Note: for `is_small()` tables group may contain the "same" slot twice:
+  // original and mirrored.
+  BitMask<uint16_t, kWidth> MaskFull() const {
+    return BitMask<uint16_t, kWidth>(
+        static_cast<uint16_t>(_mm_movemask_epi8(ctrl) ^ 0xffff));
+  }
+
   // Returns a bitmask representing the positions of empty or deleted slots.
-  NonIterableBitMask<uint32_t, kWidth> MaskEmptyOrDeleted() const {
+  NonIterableBitMask<uint16_t, kWidth> MaskEmptyOrDeleted() const {
     auto special = _mm_set1_epi8(static_cast<char>(ctrl_t::kSentinel));
-    return NonIterableBitMask<uint32_t, kWidth>(static_cast<uint32_t>(
+    return NonIterableBitMask<uint16_t, kWidth>(static_cast<uint16_t>(
         _mm_movemask_epi8(_mm_cmpgt_epi8_fixed(special, ctrl))));
   }
 
@@ -651,9 +688,8 @@ struct GroupAArch64Impl {
   BitMask<uint64_t, kWidth, 3> Match(h2_t hash) const {
     uint8x8_t dup = vdup_n_u8(hash);
     auto mask = vceq_u8(ctrl, dup);
-    constexpr uint64_t msbs = 0x8080808080808080ULL;
     return BitMask<uint64_t, kWidth, 3>(
-        vget_lane_u64(vreinterpret_u64_u8(mask), 0) & msbs);
+        vget_lane_u64(vreinterpret_u64_u8(mask), 0));
   }
 
   NonIterableBitMask<uint64_t, kWidth, 3> MaskEmpty() const {
@@ -665,6 +701,17 @@ struct GroupAArch64Impl {
     return NonIterableBitMask<uint64_t, kWidth, 3>(mask);
   }
 
+  // Returns a bitmask representing the positions of full slots.
+  // Note: for `is_small()` tables group may contain the "same" slot twice:
+  // original and mirrored.
+  BitMask<uint64_t, kWidth, 3> MaskFull() const {
+    uint64_t mask = vget_lane_u64(
+        vreinterpret_u64_u8(vcge_s8(vreinterpret_s8_u8(ctrl),
+                                    vdup_n_s8(static_cast<int8_t>(0)))),
+        0);
+    return BitMask<uint64_t, kWidth, 3>(mask);
+  }
+
   NonIterableBitMask<uint64_t, kWidth, 3> MaskEmptyOrDeleted() const {
     uint64_t mask =
         vget_lane_u64(vreinterpret_u64_u8(vcgt_s8(
@@ -729,13 +776,21 @@ struct GroupPortableImpl {
 
   NonIterableBitMask<uint64_t, kWidth, 3> MaskEmpty() const {
     constexpr uint64_t msbs = 0x8080808080808080ULL;
-    return NonIterableBitMask<uint64_t, kWidth, 3>((ctrl & (~ctrl << 6)) &
+    return NonIterableBitMask<uint64_t, kWidth, 3>((ctrl & ~(ctrl << 6)) &
                                                    msbs);
   }
 
+  // Returns a bitmask representing the positions of full slots.
+  // Note: for `is_small()` tables group may contain the "same" slot twice:
+  // original and mirrored.
+  BitMask<uint64_t, kWidth, 3> MaskFull() const {
+    constexpr uint64_t msbs = 0x8080808080808080ULL;
+    return BitMask<uint64_t, kWidth, 3>((ctrl ^ msbs) & msbs);
+  }
+
   NonIterableBitMask<uint64_t, kWidth, 3> MaskEmptyOrDeleted() const {
     constexpr uint64_t msbs = 0x8080808080808080ULL;
-    return NonIterableBitMask<uint64_t, kWidth, 3>((ctrl & (~ctrl << 7)) &
+    return NonIterableBitMask<uint64_t, kWidth, 3>((ctrl & ~(ctrl << 7)) &
                                                    msbs);
   }
 
@@ -760,10 +815,21 @@ struct GroupPortableImpl {
 
 #ifdef ABSL_INTERNAL_HAVE_SSE2
 using Group = GroupSse2Impl;
+using GroupEmptyOrDeleted = GroupSse2Impl;
 #elif defined(ABSL_INTERNAL_HAVE_ARM_NEON) && defined(ABSL_IS_LITTLE_ENDIAN)
 using Group = GroupAArch64Impl;
+// For Aarch64, we use the portable implementation for counting and masking
+// empty or deleted group elements. This is to avoid the latency of moving
+// between data GPRs and Neon registers when it does not provide a benefit.
+// Using Neon is profitable when we call Match(), but is not when we don't,
+// which is the case when we do *EmptyOrDeleted operations. It is difficult to
+// make a similar approach beneficial on other architectures such as x86 since
+// they have much lower GPR <-> vector register transfer latency and 16-wide
+// Groups.
+using GroupEmptyOrDeleted = GroupPortableImpl;
 #else
 using Group = GroupPortableImpl;
+using GroupEmptyOrDeleted = GroupPortableImpl;
 #endif
 
 // When there is an insertion with no reserved growth, we rehash with
@@ -802,15 +868,19 @@ class CommonFieldsGenerationInfoEnabled {
   // whenever reserved_growth_ is zero.
   bool should_rehash_for_bug_detection_on_insert(const ctrl_t* ctrl,
                                                  size_t capacity) const;
+  // Similar to above, except that we don't depend on reserved_growth_.
+  bool should_rehash_for_bug_detection_on_move(const ctrl_t* ctrl,
+                                               size_t capacity) const;
   void maybe_increment_generation_on_insert() {
     if (reserved_growth_ == kReservedGrowthJustRanOut) reserved_growth_ = 0;
 
     if (reserved_growth_ > 0) {
       if (--reserved_growth_ == 0) reserved_growth_ = kReservedGrowthJustRanOut;
     } else {
-      *generation_ = NextGeneration(*generation_);
+      increment_generation();
     }
   }
+  void increment_generation() { *generation_ = NextGeneration(*generation_); }
   void reset_reserved_growth(size_t reservation, size_t size) {
     reserved_growth_ = reservation - size;
   }
@@ -856,7 +926,11 @@ class CommonFieldsGenerationInfoDisabled {
   bool should_rehash_for_bug_detection_on_insert(const ctrl_t*, size_t) const {
     return false;
   }
+  bool should_rehash_for_bug_detection_on_move(const ctrl_t*, size_t) const {
+    return false;
+  }
   void maybe_increment_generation_on_insert() {}
+  void increment_generation() {}
   void reset_reserved_growth(size_t, size_t) {}
   size_t reserved_growth() const { return 0; }
   void set_reserved_growth(size_t) {}
@@ -909,9 +983,11 @@ using HashSetIteratorGenerationInfo = HashSetIteratorGenerationInfoDisabled;
 // A valid capacity is a non-zero integer `2^m - 1`.
 inline bool IsValidCapacity(size_t n) { return ((n + 1) & n) == 0 && n > 0; }
 
-// Computes the offset from the start of the backing allocation of the control
-// bytes. growth_left is stored at the beginning of the backing array.
-inline size_t ControlOffset() { return sizeof(size_t); }
+// Computes the offset from the start of the backing allocation of control.
+// infoz and growth_left are stored at the beginning of the backing array.
+inline size_t ControlOffset(bool has_infoz) {
+  return (has_infoz ? sizeof(HashtablezInfoHandle) : 0) + sizeof(size_t);
+}
 
 // Returns the number of "cloned control bytes".
 //
@@ -922,24 +998,26 @@ constexpr size_t NumClonedBytes() { return Group::kWidth - 1; }
 
 // Given the capacity of a table, computes the offset (from the start of the
 // backing allocation) of the generation counter (if it exists).
-inline size_t GenerationOffset(size_t capacity) {
+inline size_t GenerationOffset(size_t capacity, bool has_infoz) {
   assert(IsValidCapacity(capacity));
   const size_t num_control_bytes = capacity + 1 + NumClonedBytes();
-  return ControlOffset() + num_control_bytes;
+  return ControlOffset(has_infoz) + num_control_bytes;
 }
 
 // Given the capacity of a table, computes the offset (from the start of the
 // backing allocation) at which the slots begin.
-inline size_t SlotOffset(size_t capacity, size_t slot_align) {
+inline size_t SlotOffset(size_t capacity, size_t slot_align, bool has_infoz) {
   assert(IsValidCapacity(capacity));
-  return (GenerationOffset(capacity) + NumGenerationBytes() + slot_align - 1) &
+  return (GenerationOffset(capacity, has_infoz) + NumGenerationBytes() +
+          slot_align - 1) &
          (~slot_align + 1);
 }
 
 // Given the capacity of a table, computes the total size of the backing
 // array.
-inline size_t AllocSize(size_t capacity, size_t slot_size, size_t slot_align) {
-  return SlotOffset(capacity, slot_align) + capacity * slot_size;
+inline size_t AllocSize(size_t capacity, size_t slot_size, size_t slot_align,
+                        bool has_infoz) {
+  return SlotOffset(capacity, slot_align, has_infoz) + capacity * slot_size;
 }
 
 // CommonFields hold the fields in raw_hash_set that do not depend
@@ -954,28 +1032,15 @@ class CommonFields : public CommonFieldsGenerationInfo {
   CommonFields& operator=(const CommonFields&) = delete;
 
   // Movable
-  CommonFields(CommonFields&& that)
-      : CommonFieldsGenerationInfo(
-            std::move(static_cast<CommonFieldsGenerationInfo&&>(that))),
-        // Explicitly copying fields into "this" and then resetting "that"
-        // fields generates less code then calling absl::exchange per field.
-        control_(that.control()),
-        slots_(that.slot_array()),
-        capacity_(that.capacity()),
-        compressed_tuple_(that.size(), std::move(that.infoz())) {
-    that.set_control(EmptyGroup());
-    that.set_slots(nullptr);
-    that.set_capacity(0);
-    that.set_size(0);
-  }
+  CommonFields(CommonFields&& that) = default;
   CommonFields& operator=(CommonFields&&) = default;
 
   ctrl_t* control() const { return control_; }
   void set_control(ctrl_t* c) { control_ = c; }
   void* backing_array_start() const {
-    // growth_left is stored before control bytes.
+    // growth_left (and maybe infoz) is stored before control bytes.
     assert(reinterpret_cast<uintptr_t>(control()) % alignof(size_t) == 0);
-    return control() - sizeof(size_t);
+    return control() - ControlOffset(has_infoz());
   }
 
   // Note: we can't use slots() because Qt defines "slots" as a macro.
@@ -983,8 +1048,18 @@ class CommonFields : public CommonFieldsGenerationInfo {
   void set_slots(void* s) { slots_ = s; }
 
   // The number of filled slots.
-  size_t size() const { return compressed_tuple_.template get<0>(); }
-  void set_size(size_t s) { compressed_tuple_.template get<0>() = s; }
+  size_t size() const { return size_ >> HasInfozShift(); }
+  void set_size(size_t s) {
+    size_ = (s << HasInfozShift()) | (size_ & HasInfozMask());
+  }
+  void increment_size() {
+    assert(size() < capacity());
+    size_ += size_t{1} << HasInfozShift();
+  }
+  void decrement_size() {
+    assert(size() > 0);
+    size_ -= size_t{1} << HasInfozShift();
+  }
 
   // The total number of available slots.
   size_t capacity() const { return capacity_; }
@@ -996,28 +1071,52 @@ class CommonFields : public CommonFieldsGenerationInfo {
   // The number of slots we can still fill without needing to rehash.
   // This is stored in the heap allocation before the control bytes.
   size_t growth_left() const {
-    return *reinterpret_cast<size_t*>(backing_array_start());
+    const size_t* gl_ptr = reinterpret_cast<size_t*>(control()) - 1;
+    assert(reinterpret_cast<uintptr_t>(gl_ptr) % alignof(size_t) == 0);
+    return *gl_ptr;
   }
   void set_growth_left(size_t gl) {
-    *reinterpret_cast<size_t*>(backing_array_start()) = gl;
+    size_t* gl_ptr = reinterpret_cast<size_t*>(control()) - 1;
+    assert(reinterpret_cast<uintptr_t>(gl_ptr) % alignof(size_t) == 0);
+    *gl_ptr = gl;
   }
 
-  HashtablezInfoHandle& infoz() { return compressed_tuple_.template get<1>(); }
-  const HashtablezInfoHandle& infoz() const {
-    return compressed_tuple_.template get<1>();
+  bool has_infoz() const {
+    return ABSL_PREDICT_FALSE((size_ & HasInfozMask()) != 0);
+  }
+  void set_has_infoz(bool has_infoz) {
+    size_ = (size() << HasInfozShift()) | static_cast<size_t>(has_infoz);
+  }
+
+  HashtablezInfoHandle infoz() {
+    return has_infoz()
+               ? *reinterpret_cast<HashtablezInfoHandle*>(backing_array_start())
+               : HashtablezInfoHandle();
+  }
+  void set_infoz(HashtablezInfoHandle infoz) {
+    assert(has_infoz());
+    *reinterpret_cast<HashtablezInfoHandle*>(backing_array_start()) = infoz;
   }
 
   bool should_rehash_for_bug_detection_on_insert() const {
     return CommonFieldsGenerationInfo::
         should_rehash_for_bug_detection_on_insert(control(), capacity());
   }
+  bool should_rehash_for_bug_detection_on_move() const {
+    return CommonFieldsGenerationInfo::
+        should_rehash_for_bug_detection_on_move(control(), capacity());
+  }
+  void maybe_increment_generation_on_move() {
+    if (capacity() == 0) return;
+    increment_generation();
+  }
   void reset_reserved_growth(size_t reservation) {
     CommonFieldsGenerationInfo::reset_reserved_growth(reservation, size());
   }
 
   // The size of the backing array allocation.
   size_t alloc_size(size_t slot_size, size_t slot_align) const {
-    return AllocSize(capacity(), slot_size, slot_align);
+    return AllocSize(capacity(), slot_size, slot_align, has_infoz());
   }
 
   // Returns the number of control bytes set to kDeleted. For testing only.
@@ -1027,9 +1126,14 @@ class CommonFields : public CommonFieldsGenerationInfo {
   }
 
  private:
-  // TODO(b/259599413): Investigate removing some of these fields:
+  // We store the has_infoz bit in the lowest bit of size_.
+  static constexpr size_t HasInfozShift() { return 1; }
+  static constexpr size_t HasInfozMask() {
+    return (size_t{1} << HasInfozShift()) - 1;
+  }
+
+  // TODO(b/182800944): Investigate removing some of these fields:
   // - control/slots can be derived from each other
-  // - we can use 6 bits for capacity since it's always a power of two minus 1
 
   // The control bytes (and, also, a pointer near to the base of the backing
   // array).
@@ -1044,12 +1148,16 @@ class CommonFields : public CommonFieldsGenerationInfo {
   // `control`. May be null for empty tables.
   void* slots_ = nullptr;
 
+  // The number of slots in the backing array. This is always 2^N-1 for an
+  // integer N. NOTE: we tried experimenting with compressing the capacity and
+  // storing it together with size_: (a) using 6 bits to store the corresponding
+  // power (N in 2^N-1), and (b) storing 2^N as the most significant bit of
+  // size_ and storing size in the low bits. Both of these experiments were
+  // regressions, presumably because we need capacity to do find operations.
   size_t capacity_ = 0;
 
-  // Bundle together size and HashtablezInfoHandle to ensure EBO for
-  // HashtablezInfoHandle when sampling is turned off.
-  absl::container_internal::CompressedTuple<size_t, HashtablezInfoHandle>
-      compressed_tuple_{0u, HashtablezInfoHandle{}};
+  // The size and also has one bit that stores whether we have infoz.
+  size_t size_ = 0;
 };
 
 template <class Policy, class Hash, class Eq, class Alloc>
@@ -1139,35 +1247,39 @@ inline void AssertIsFull(const ctrl_t* ctrl, GenerationType generation,
                          const GenerationType* generation_ptr,
                          const char* operation) {
   if (!SwisstableDebugEnabled()) return;
-  if (ctrl == nullptr) {
-    ABSL_INTERNAL_LOG(FATAL,
-                      std::string(operation) + " called on end() iterator.");
-  }
-  if (ctrl == EmptyGroup()) {
-    ABSL_INTERNAL_LOG(FATAL, std::string(operation) +
-                                 " called on default-constructed iterator.");
+  // `SwisstableDebugEnabled()` is also true for release builds with hardening
+  // enabled. To minimize their impact in those builds:
+  // - use `ABSL_PREDICT_FALSE()` to provide a compiler hint for code layout
+  // - use `ABSL_RAW_LOG()` with a format string to reduce code size and improve
+  //   the chances that the hot paths will be inlined.
+  if (ABSL_PREDICT_FALSE(ctrl == nullptr)) {
+    ABSL_RAW_LOG(FATAL, "%s called on end() iterator.", operation);
+  }
+  if (ABSL_PREDICT_FALSE(ctrl == EmptyGroup())) {
+    ABSL_RAW_LOG(FATAL, "%s called on default-constructed iterator.",
+                 operation);
   }
   if (SwisstableGenerationsEnabled()) {
-    if (generation != *generation_ptr) {
-      ABSL_INTERNAL_LOG(FATAL,
-                        std::string(operation) +
-                            " called on invalid iterator. The table could have "
-                            "rehashed since this iterator was initialized.");
+    if (ABSL_PREDICT_FALSE(generation != *generation_ptr)) {
+      ABSL_RAW_LOG(FATAL,
+                   "%s called on invalid iterator. The table could have "
+                   "rehashed or moved since this iterator was initialized.",
+                   operation);
     }
-    if (!IsFull(*ctrl)) {
-      ABSL_INTERNAL_LOG(
+    if (ABSL_PREDICT_FALSE(!IsFull(*ctrl))) {
+      ABSL_RAW_LOG(
           FATAL,
-          std::string(operation) +
-              " called on invalid iterator. The element was likely erased.");
+          "%s called on invalid iterator. The element was likely erased.",
+          operation);
     }
   } else {
-    if (!IsFull(*ctrl)) {
-      ABSL_INTERNAL_LOG(
+    if (ABSL_PREDICT_FALSE(!IsFull(*ctrl))) {
+      ABSL_RAW_LOG(
           FATAL,
-          std::string(operation) +
-              " called on invalid iterator. The element might have been erased "
-              "or the table might have rehashed. Consider running with "
-              "--config=asan to diagnose rehashing issues.");
+          "%s called on invalid iterator. The element might have been erased "
+          "or the table might have rehashed. Consider running with "
+          "--config=asan to diagnose rehashing issues.",
+          operation);
     }
   }
 }
@@ -1180,13 +1292,13 @@ inline void AssertIsValidForComparison(const ctrl_t* ctrl,
   const bool ctrl_is_valid_for_comparison =
       ctrl == nullptr || ctrl == EmptyGroup() || IsFull(*ctrl);
   if (SwisstableGenerationsEnabled()) {
-    if (generation != *generation_ptr) {
-      ABSL_INTERNAL_LOG(FATAL,
-                        "Invalid iterator comparison. The table could have "
-                        "rehashed since this iterator was initialized.");
+    if (ABSL_PREDICT_FALSE(generation != *generation_ptr)) {
+      ABSL_RAW_LOG(FATAL,
+                   "Invalid iterator comparison. The table could have rehashed "
+                   "or moved since this iterator was initialized.");
     }
-    if (!ctrl_is_valid_for_comparison) {
-      ABSL_INTERNAL_LOG(
+    if (ABSL_PREDICT_FALSE(!ctrl_is_valid_for_comparison)) {
+      ABSL_RAW_LOG(
           FATAL, "Invalid iterator comparison. The element was likely erased.");
     }
   } else {
@@ -1226,10 +1338,15 @@ inline void AssertSameContainer(const ctrl_t* ctrl_a, const ctrl_t* ctrl_b,
                                 const GenerationType* generation_ptr_a,
                                 const GenerationType* generation_ptr_b) {
   if (!SwisstableDebugEnabled()) return;
+  // `SwisstableDebugEnabled()` is also true for release builds with hardening
+  // enabled. To minimize their impact in those builds:
+  // - use `ABSL_PREDICT_FALSE()` to provide a compiler hint for code layout
+  // - use `ABSL_RAW_LOG()` with a format string to reduce code size and improve
+  //   the chances that the hot paths will be inlined.
   const bool a_is_default = ctrl_a == EmptyGroup();
   const bool b_is_default = ctrl_b == EmptyGroup();
-  if (a_is_default != b_is_default) {
-    ABSL_INTERNAL_LOG(
+  if (ABSL_PREDICT_FALSE(a_is_default != b_is_default)) {
+    ABSL_RAW_LOG(
         FATAL,
         "Invalid iterator comparison. Comparing default-constructed iterator "
         "with non-default-constructed iterator.");
@@ -1237,36 +1354,36 @@ inline void AssertSameContainer(const ctrl_t* ctrl_a, const ctrl_t* ctrl_b,
   if (a_is_default && b_is_default) return;
 
   if (SwisstableGenerationsEnabled()) {
-    if (generation_ptr_a == generation_ptr_b) return;
+    if (ABSL_PREDICT_TRUE(generation_ptr_a == generation_ptr_b)) return;
     const bool a_is_empty = IsEmptyGeneration(generation_ptr_a);
     const bool b_is_empty = IsEmptyGeneration(generation_ptr_b);
     if (a_is_empty != b_is_empty) {
-      ABSL_INTERNAL_LOG(FATAL,
-                        "Invalid iterator comparison. Comparing iterator from "
-                        "a non-empty hashtable with an iterator from an empty "
-                        "hashtable.");
+      ABSL_RAW_LOG(FATAL,
+                   "Invalid iterator comparison. Comparing iterator from a "
+                   "non-empty hashtable with an iterator from an empty "
+                   "hashtable.");
     }
     if (a_is_empty && b_is_empty) {
-      ABSL_INTERNAL_LOG(FATAL,
-                        "Invalid iterator comparison. Comparing iterators from "
-                        "different empty hashtables.");
+      ABSL_RAW_LOG(FATAL,
+                   "Invalid iterator comparison. Comparing iterators from "
+                   "different empty hashtables.");
     }
     const bool a_is_end = ctrl_a == nullptr;
     const bool b_is_end = ctrl_b == nullptr;
     if (a_is_end || b_is_end) {
-      ABSL_INTERNAL_LOG(FATAL,
-                        "Invalid iterator comparison. Comparing iterator with "
-                        "an end() iterator from a different hashtable.");
+      ABSL_RAW_LOG(FATAL,
+                   "Invalid iterator comparison. Comparing iterator with an "
+                   "end() iterator from a different hashtable.");
     }
-    ABSL_INTERNAL_LOG(FATAL,
-                      "Invalid iterator comparison. Comparing non-end() "
-                      "iterators from different hashtables.");
+    ABSL_RAW_LOG(FATAL,
+                 "Invalid iterator comparison. Comparing non-end() iterators "
+                 "from different hashtables.");
   } else {
     ABSL_HARDENING_ASSERT(
         AreItersFromSameContainer(ctrl_a, ctrl_b, slot_a, slot_b) &&
         "Invalid iterator comparison. The iterators may be from different "
-        "containers or the container might have rehashed. Consider running "
-        "with --config=asan to diagnose rehashing issues.");
+        "containers or the container might have rehashed or moved. Consider "
+        "running with --config=asan to diagnose issues.");
   }
 }
 
@@ -1289,6 +1406,12 @@ struct FindInfo {
 // `ShouldInsertBackwards()` for small tables.
 inline bool is_small(size_t capacity) { return capacity < Group::kWidth - 1; }
 
+// Whether a table fits entirely into a probing group.
+// Arbitrary order of elements in such tables is correct.
+inline bool is_single_group(size_t capacity) {
+  return capacity <= Group::kWidth;
+}
+
 // Begins a probing operation on `common.control`, using `hash`.
 inline probe_seq<Group::kWidth> probe(const ctrl_t* ctrl, const size_t capacity,
                                       size_t hash) {
@@ -1310,7 +1433,7 @@ inline FindInfo find_first_non_full(const CommonFields& common, size_t hash) {
   auto seq = probe(common, hash);
   const ctrl_t* ctrl = common.control();
   while (true) {
-    Group g{ctrl + seq.offset()};
+    GroupEmptyOrDeleted g{ctrl + seq.offset()};
     auto mask = g.MaskEmptyOrDeleted();
     if (mask) {
 #if !defined(NDEBUG)
@@ -1351,7 +1474,6 @@ inline void ResetCtrl(CommonFields& common, size_t slot_size) {
               capacity + 1 + NumClonedBytes());
   ctrl[capacity] = ctrl_t::kSentinel;
   SanitizerPoisonMemoryRegion(common.slot_array(), slot_size * capacity);
-  ResetGrowthLeft(common);
 }
 
 // Sets `ctrl[i]` to `h`.
@@ -1386,38 +1508,263 @@ constexpr size_t BackingArrayAlignment(size_t align_of_slot) {
   return (std::max)(align_of_slot, alignof(size_t));
 }
 
-template <typename Alloc, size_t SizeOfSlot, size_t AlignOfSlot>
-ABSL_ATTRIBUTE_NOINLINE void InitializeSlots(CommonFields& c, Alloc alloc) {
-  assert(c.capacity());
-  // Folks with custom allocators often make unwarranted assumptions about the
-  // behavior of their classes vis-a-vis trivial destructability and what
-  // calls they will or won't make.  Avoid sampling for people with custom
-  // allocators to get us out of this mess.  This is not a hard guarantee but
-  // a workaround while we plan the exact guarantee we want to provide.
-  const size_t sample_size =
-      (std::is_same<Alloc, std::allocator<char>>::value &&
-       c.slot_array() == nullptr)
-          ? SizeOfSlot
-          : 0;
-
-  const size_t cap = c.capacity();
-  const size_t alloc_size = AllocSize(cap, SizeOfSlot, AlignOfSlot);
-  // growth_left (which is a size_t) is stored with the backing array.
-  char* mem = static_cast<char*>(
-      Allocate<BackingArrayAlignment(AlignOfSlot)>(&alloc, alloc_size));
-  const GenerationType old_generation = c.generation();
-  c.set_generation_ptr(
-      reinterpret_cast<GenerationType*>(mem + GenerationOffset(cap)));
-  c.set_generation(NextGeneration(old_generation));
-  c.set_control(reinterpret_cast<ctrl_t*>(mem + ControlOffset()));
-  c.set_slots(mem + SlotOffset(cap, AlignOfSlot));
-  ResetCtrl(c, SizeOfSlot);
-  if (sample_size) {
-    c.infoz() = Sample(sample_size);
-  }
-  c.infoz().RecordStorageChanged(c.size(), cap);
+// Returns the address of the ith slot in slots where each slot occupies
+// slot_size.
+inline void* SlotAddress(void* slot_array, size_t slot, size_t slot_size) {
+  return reinterpret_cast<void*>(reinterpret_cast<char*>(slot_array) +
+                                 (slot * slot_size));
 }
 
+// Helper class to perform resize of the hash set.
+//
+// It contains special optimizations for small group resizes.
+// See GrowIntoSingleGroupShuffleControlBytes for details.
+class HashSetResizeHelper {
+ public:
+  explicit HashSetResizeHelper(CommonFields& c)
+      : old_ctrl_(c.control()),
+        old_capacity_(c.capacity()),
+        had_infoz_(c.has_infoz()) {}
+
+  // Optimized for small groups version of `find_first_non_full` applicable
+  // only right after calling `raw_hash_set::resize`.
+  // It has implicit assumption that `resize` will call
+  // `GrowSizeIntoSingleGroup*` in case `IsGrowingIntoSingleGroupApplicable`.
+  // Falls back to `find_first_non_full` in case of big groups, so it is
+  // safe to use after `rehash_and_grow_if_necessary`.
+  static FindInfo FindFirstNonFullAfterResize(const CommonFields& c,
+                                              size_t old_capacity,
+                                              size_t hash) {
+    if (!IsGrowingIntoSingleGroupApplicable(old_capacity, c.capacity())) {
+      return find_first_non_full(c, hash);
+    }
+    // Find a location for the new element non-deterministically.
+    // Note that any position is correct.
+    // It will located at `half_old_capacity` or one of the other
+    // empty slots with approximately 50% probability each.
+    size_t offset = probe(c, hash).offset();
+
+    // Note that we intentionally use unsigned int underflow.
+    if (offset - (old_capacity + 1) >= old_capacity) {
+      // Offset fall on kSentinel or into the mostly occupied first half.
+      offset = old_capacity / 2;
+    }
+    assert(IsEmpty(c.control()[offset]));
+    return FindInfo{offset, 0};
+  }
+
+  ctrl_t* old_ctrl() const { return old_ctrl_; }
+  size_t old_capacity() const { return old_capacity_; }
+
+  // Allocates a backing array for the hashtable.
+  // Reads `capacity` and updates all other fields based on the result of
+  // the allocation.
+  //
+  // It also may do the folowing actions:
+  // 1. initialize control bytes
+  // 2. initialize slots
+  // 3. deallocate old slots.
+  //
+  // We are bundling a lot of functionality
+  // in one ABSL_ATTRIBUTE_NOINLINE function in order to minimize binary code
+  // duplication in raw_hash_set<>::resize.
+  //
+  // `c.capacity()` must be nonzero.
+  // POSTCONDITIONS:
+  //  1. CommonFields is initialized.
+  //
+  //  if IsGrowingIntoSingleGroupApplicable && TransferUsesMemcpy
+  //    Both control bytes and slots are fully initialized.
+  //    old_slots are deallocated.
+  //    infoz.RecordRehash is called.
+  //
+  //  if IsGrowingIntoSingleGroupApplicable && !TransferUsesMemcpy
+  //    Control bytes are fully initialized.
+  //    infoz.RecordRehash is called.
+  //    GrowSizeIntoSingleGroup must be called to finish slots initialization.
+  //
+  //  if !IsGrowingIntoSingleGroupApplicable
+  //    Control bytes are initialized to empty table via ResetCtrl.
+  //    raw_hash_set<>::resize must insert elements regularly.
+  //    infoz.RecordRehash is called if old_capacity == 0.
+  //
+  //  Returns IsGrowingIntoSingleGroupApplicable result to avoid recomputation.
+  template <typename Alloc, size_t SizeOfSlot, bool TransferUsesMemcpy,
+            size_t AlignOfSlot>
+  ABSL_ATTRIBUTE_NOINLINE bool InitializeSlots(CommonFields& c, void* old_slots,
+                                               Alloc alloc) {
+    assert(c.capacity());
+    // Folks with custom allocators often make unwarranted assumptions about the
+    // behavior of their classes vis-a-vis trivial destructability and what
+    // calls they will or won't make.  Avoid sampling for people with custom
+    // allocators to get us out of this mess.  This is not a hard guarantee but
+    // a workaround while we plan the exact guarantee we want to provide.
+    const size_t sample_size =
+        (std::is_same<Alloc, std::allocator<char>>::value &&
+         c.slot_array() == nullptr)
+            ? SizeOfSlot
+            : 0;
+    HashtablezInfoHandle infoz =
+        sample_size > 0 ? Sample(sample_size) : c.infoz();
+
+    const bool has_infoz = infoz.IsSampled();
+    const size_t cap = c.capacity();
+    const size_t alloc_size =
+        AllocSize(cap, SizeOfSlot, AlignOfSlot, has_infoz);
+    char* mem = static_cast<char*>(
+        Allocate<BackingArrayAlignment(AlignOfSlot)>(&alloc, alloc_size));
+    const GenerationType old_generation = c.generation();
+    c.set_generation_ptr(reinterpret_cast<GenerationType*>(
+        mem + GenerationOffset(cap, has_infoz)));
+    c.set_generation(NextGeneration(old_generation));
+    c.set_control(reinterpret_cast<ctrl_t*>(mem + ControlOffset(has_infoz)));
+    c.set_slots(mem + SlotOffset(cap, AlignOfSlot, has_infoz));
+    ResetGrowthLeft(c);
+
+    const bool grow_single_group =
+        IsGrowingIntoSingleGroupApplicable(old_capacity_, c.capacity());
+    if (old_capacity_ != 0 && grow_single_group) {
+      if (TransferUsesMemcpy) {
+        GrowSizeIntoSingleGroupTransferable(c, old_slots, SizeOfSlot);
+        DeallocateOld<AlignOfSlot>(alloc, SizeOfSlot, old_slots);
+      } else {
+        GrowIntoSingleGroupShuffleControlBytes(c.control(), c.capacity());
+      }
+    } else {
+      ResetCtrl(c, SizeOfSlot);
+    }
+
+    c.set_has_infoz(has_infoz);
+    if (has_infoz) {
+      infoz.RecordStorageChanged(c.size(), cap);
+      if (grow_single_group || old_capacity_ == 0) {
+        infoz.RecordRehash(0);
+      }
+      c.set_infoz(infoz);
+    }
+    return grow_single_group;
+  }
+
+  // Relocates slots into new single group consistent with
+  // GrowIntoSingleGroupShuffleControlBytes.
+  //
+  // PRECONDITIONS:
+  // 1. GrowIntoSingleGroupShuffleControlBytes was already called.
+  template <class PolicyTraits, class Alloc>
+  void GrowSizeIntoSingleGroup(CommonFields& c, Alloc& alloc_ref,
+                               typename PolicyTraits::slot_type* old_slots) {
+    assert(old_capacity_ < Group::kWidth / 2);
+    assert(IsGrowingIntoSingleGroupApplicable(old_capacity_, c.capacity()));
+    using slot_type = typename PolicyTraits::slot_type;
+    assert(is_single_group(c.capacity()));
+
+    auto* new_slots = reinterpret_cast<slot_type*>(c.slot_array());
+
+    size_t shuffle_bit = old_capacity_ / 2 + 1;
+    for (size_t i = 0; i < old_capacity_; ++i) {
+      if (IsFull(old_ctrl_[i])) {
+        size_t new_i = i ^ shuffle_bit;
+        SanitizerUnpoisonMemoryRegion(new_slots + new_i, sizeof(slot_type));
+        PolicyTraits::transfer(&alloc_ref, new_slots + new_i, old_slots + i);
+      }
+    }
+    PoisonSingleGroupEmptySlots(c, sizeof(slot_type));
+  }
+
+  // Deallocates old backing array.
+  template <size_t AlignOfSlot, class CharAlloc>
+  void DeallocateOld(CharAlloc alloc_ref, size_t slot_size, void* old_slots) {
+    SanitizerUnpoisonMemoryRegion(old_slots, slot_size * old_capacity_);
+    Deallocate<BackingArrayAlignment(AlignOfSlot)>(
+        &alloc_ref, old_ctrl_ - ControlOffset(had_infoz_),
+        AllocSize(old_capacity_, slot_size, AlignOfSlot, had_infoz_));
+  }
+
+ private:
+  // Returns true if `GrowSizeIntoSingleGroup` can be used for resizing.
+  static bool IsGrowingIntoSingleGroupApplicable(size_t old_capacity,
+                                                 size_t new_capacity) {
+    // NOTE that `old_capacity < new_capacity` in order to have
+    // `old_capacity < Group::kWidth / 2` to make faster copies of 8 bytes.
+    return is_single_group(new_capacity) && old_capacity < new_capacity;
+  }
+
+  // Relocates control bytes and slots into new single group for
+  // transferable objects.
+  // Must be called only if IsGrowingIntoSingleGroupApplicable returned true.
+  void GrowSizeIntoSingleGroupTransferable(CommonFields& c, void* old_slots,
+                                           size_t slot_size);
+
+  // Shuffle control bits deterministically to the next capacity.
+  // Returns offset for newly added element with given hash.
+  //
+  // PRECONDITIONs:
+  // 1. new_ctrl is allocated for new_capacity,
+  //    but not initialized.
+  // 2. new_capacity is a single group.
+  //
+  // All elements are transferred into the first `old_capacity + 1` positions
+  // of the new_ctrl. Elements are rotated by `old_capacity_ / 2 + 1` positions
+  // in order to change an order and keep it non deterministic.
+  // Although rotation itself deterministic, position of the new added element
+  // will be based on `H1` and is not deterministic.
+  //
+  // Examples:
+  // S = kSentinel, E = kEmpty
+  //
+  // old_ctrl = SEEEEEEEE...
+  // new_ctrl = ESEEEEEEE...
+  //
+  // old_ctrl = 0SEEEEEEE...
+  // new_ctrl = E0ESE0EEE...
+  //
+  // old_ctrl = 012S012EEEEEEEEE...
+  // new_ctrl = 2E01EEES2E01EEE...
+  //
+  // old_ctrl = 0123456S0123456EEEEEEEEEEE...
+  // new_ctrl = 456E0123EEEEEES456E0123EEE...
+  void GrowIntoSingleGroupShuffleControlBytes(ctrl_t* new_ctrl,
+                                              size_t new_capacity) const;
+
+  // Shuffle trivially transferable slots in the way consistent with
+  // GrowIntoSingleGroupShuffleControlBytes.
+  //
+  // PRECONDITIONs:
+  // 1. old_capacity must be non-zero.
+  // 2. new_ctrl is fully initialized using
+  //    GrowIntoSingleGroupShuffleControlBytes.
+  // 3. new_slots is allocated and *not* poisoned.
+  //
+  // POSTCONDITIONS:
+  // 1. new_slots are transferred from old_slots_ consistent with
+  //    GrowIntoSingleGroupShuffleControlBytes.
+  // 2. Empty new_slots are *not* poisoned.
+  void GrowIntoSingleGroupShuffleTransferableSlots(void* old_slots,
+                                                   void* new_slots,
+                                                   size_t slot_size) const;
+
+  // Poison empty slots that were transferred using the deterministic algorithm
+  // described above.
+  // PRECONDITIONs:
+  // 1. new_ctrl is fully initialized using
+  //    GrowIntoSingleGroupShuffleControlBytes.
+  // 2. new_slots is fully initialized consistent with
+  //    GrowIntoSingleGroupShuffleControlBytes.
+  void PoisonSingleGroupEmptySlots(CommonFields& c, size_t slot_size) const {
+    // poison non full items
+    for (size_t i = 0; i < c.capacity(); ++i) {
+      if (!IsFull(c.control()[i])) {
+        SanitizerPoisonMemoryRegion(SlotAddress(c.slot_array(), i, slot_size),
+                                    slot_size);
+      }
+    }
+  }
+
+  ctrl_t* old_ctrl_;
+  size_t old_capacity_;
+  bool had_infoz_;
+};
+
 // PolicyFunctions bundles together some information for a particular
 // raw_hash_set<T, ...> instantiation. This information is passed to
 // type-erased functions that want to do small amounts of type-specific
@@ -1442,7 +1789,7 @@ void ClearBackingArray(CommonFields& c, const PolicyFunctions& policy,
                        bool reuse);
 
 // Type-erased version of raw_hash_set::erase_meta_only.
-void EraseMetaOnly(CommonFields& c, ctrl_t* it, size_t slot_size);
+void EraseMetaOnly(CommonFields& c, size_t index, size_t slot_size);
 
 // Function to place in PolicyFunctions::dealloc for raw_hash_sets
 // that are using std::allocator. This allows us to share the same
@@ -1456,6 +1803,7 @@ ABSL_ATTRIBUTE_NOINLINE void DeallocateStandard(CommonFields& common,
                                 policy.slot_size * common.capacity());
 
   std::allocator<char> alloc;
+  common.infoz().Unregister();
   Deallocate<BackingArrayAlignment(AlignOfSlot)>(
       &alloc, common.backing_array_start(),
       common.alloc_size(policy.slot_size, AlignOfSlot));
@@ -1534,6 +1882,11 @@ class raw_hash_set {
   using AllocTraits = absl::allocator_traits<allocator_type>;
   using SlotAlloc = typename absl::allocator_traits<
       allocator_type>::template rebind_alloc<slot_type>;
+  // People are often sloppy with the exact type of their allocator (sometimes
+  // it has an extra const or is missing the pair, but rebinds made it work
+  // anyway).
+  using CharAlloc =
+      typename absl::allocator_traits<Alloc>::template rebind_alloc<char>;
   using SlotAllocTraits = typename absl::allocator_traits<
       allocator_type>::template rebind_traits<slot_type>;
 
@@ -1590,7 +1943,7 @@ class raw_hash_set {
     // PRECONDITION: not an end() iterator.
     reference operator*() const {
       AssertIsFull(ctrl_, generation(), generation_ptr(), "operator*()");
-      return PolicyTraits::element(slot_);
+      return unchecked_deref();
     }
 
     // PRECONDITION: not an end() iterator.
@@ -1645,13 +1998,17 @@ class raw_hash_set {
     // If a sentinel is reached, we null `ctrl_` out instead.
     void skip_empty_or_deleted() {
       while (IsEmptyOrDeleted(*ctrl_)) {
-        uint32_t shift = Group{ctrl_}.CountLeadingEmptyOrDeleted();
+        uint32_t shift =
+            GroupEmptyOrDeleted{ctrl_}.CountLeadingEmptyOrDeleted();
         ctrl_ += shift;
         slot_ += shift;
       }
       if (ABSL_PREDICT_FALSE(*ctrl_ == ctrl_t::kSentinel)) ctrl_ = nullptr;
     }
 
+    ctrl_t* control() const { return ctrl_; }
+    slot_type* slot() const { return slot_; }
+
     // We use EmptyGroup() for default-constructed iterators so that they can
     // be distinguished from end iterators, which have nullptr ctrl_.
     ctrl_t* ctrl_ = EmptyGroup();
@@ -1660,10 +2017,23 @@ class raw_hash_set {
     union {
       slot_type* slot_;
     };
+
+    // An equality check which skips ABSL Hardening iterator invalidation
+    // checks.
+    // Should be used when the lifetimes of the iterators are well-enough
+    // understood to prove that they cannot be invalid.
+    bool unchecked_equals(const iterator& b) { return ctrl_ == b.control(); }
+
+    // Dereferences the iterator without ABSL Hardening iterator invalidation
+    // checks.
+    reference unchecked_deref() const { return PolicyTraits::element(slot_); }
   };
 
   class const_iterator {
     friend class raw_hash_set;
+    template <class Container, typename Enabler>
+    friend struct absl::container_internal::hashtable_debug_internal::
+        HashtableDebugAccess;
 
    public:
     using iterator_category = typename iterator::iterator_category;
@@ -1697,8 +2067,14 @@ class raw_hash_set {
                    const GenerationType* gen)
         : inner_(const_cast<ctrl_t*>(ctrl), const_cast<slot_type*>(slot), gen) {
     }
+    ctrl_t* control() const { return inner_.control(); }
+    slot_type* slot() const { return inner_.slot(); }
 
     iterator inner_;
+
+    bool unchecked_equals(const const_iterator& b) {
+      return inner_.unchecked_equals(b.inner_);
+    }
   };
 
   using node_type = node_handle<Policy, hash_policy_traits<Policy>, Alloc>;
@@ -1717,8 +2093,7 @@ class raw_hash_set {
       const allocator_type& alloc = allocator_type())
       : settings_(CommonFields{}, hash, eq, alloc) {
     if (bucket_count) {
-      common().set_capacity(NormalizeCapacity(bucket_count));
-      initialize_slots();
+      resize(NormalizeCapacity(bucket_count));
     }
   }
 
@@ -1843,28 +2218,35 @@ class raw_hash_set {
       :  // Hash, equality and allocator are copied instead of moved because
          // `that` must be left valid. If Hash is std::function<Key>, moving it
          // would create a nullptr functor that cannot be called.
-        settings_(absl::exchange(that.common(), CommonFields{}),
-                  that.hash_ref(), that.eq_ref(), that.alloc_ref()) {}
+         // TODO(b/296061262): move instead of copying hash/eq/alloc.
+         // Note: we avoid using exchange for better generated code.
+        settings_(std::move(that.common()), that.hash_ref(), that.eq_ref(),
+                  that.alloc_ref()) {
+    that.common() = CommonFields{};
+    maybe_increment_generation_or_rehash_on_move();
+  }
 
   raw_hash_set(raw_hash_set&& that, const allocator_type& a)
       : settings_(CommonFields{}, that.hash_ref(), that.eq_ref(), a) {
     if (a == that.alloc_ref()) {
       std::swap(common(), that.common());
+      maybe_increment_generation_or_rehash_on_move();
     } else {
-      reserve(that.size());
-      // Note: this will copy elements of dense_set and unordered_set instead of
-      // moving them. This can be fixed if it ever becomes an issue.
-      for (auto& elem : that) insert(std::move(elem));
+      move_elements_allocs_unequal(std::move(that));
     }
   }
 
   raw_hash_set& operator=(const raw_hash_set& that) {
-    raw_hash_set tmp(that,
-                     AllocTraits::propagate_on_container_copy_assignment::value
-                         ? that.alloc_ref()
-                         : alloc_ref());
-    swap(tmp);
-    return *this;
+    if (ABSL_PREDICT_FALSE(this == &that)) return *this;
+    constexpr bool propagate_alloc =
+        AllocTraits::propagate_on_container_copy_assignment::value;
+    // TODO(ezb): maybe avoid allocating a new backing array if this->capacity()
+    // is an exact match for that.size(). If this->capacity() is too big, then
+    // it would make iteration very slow to reuse the allocation. Maybe we can
+    // do the same heuristic as clear() and reuse if it's small enough.
+    raw_hash_set tmp(that, propagate_alloc ? that.alloc_ref() : alloc_ref());
+    // NOLINTNEXTLINE: not returning *this for performance.
+    return assign_impl<propagate_alloc>(std::move(tmp));
   }
 
   raw_hash_set& operator=(raw_hash_set&& that) noexcept(
@@ -1879,19 +2261,7 @@ class raw_hash_set {
         typename AllocTraits::propagate_on_container_move_assignment());
   }
 
-  ~raw_hash_set() {
-    const size_t cap = capacity();
-    if (!cap) return;
-    destroy_slots();
-
-    // Unpoison before returning the memory to the allocator.
-    SanitizerUnpoisonMemoryRegion(slot_array(), sizeof(slot_type) * cap);
-    Deallocate<BackingArrayAlignment(alignof(slot_type))>(
-        &alloc_ref(), common().backing_array_start(),
-        AllocSize(cap, sizeof(slot_type), alignof(slot_type)));
-
-    infoz().Unregister();
-  }
+  ~raw_hash_set() { destructor_impl(); }
 
   iterator begin() ABSL_ATTRIBUTE_LIFETIME_BOUND {
     auto it = iterator_at(0);
@@ -1937,17 +2307,6 @@ class raw_hash_set {
     common().set_reservation_size(0);
   }
 
-  inline void destroy_slots() {
-    const size_t cap = capacity();
-    const ctrl_t* ctrl = control();
-    slot_type* slot = slot_array();
-    for (size_t i = 0; i != cap; ++i) {
-      if (IsFull(ctrl[i])) {
-        PolicyTraits::destroy(&alloc_ref(), slot + i);
-      }
-    }
-  }
-
   // This overload kicks in when the argument is an rvalue of insertable and
   // decomposable type other than init_type.
   //
@@ -2075,7 +2434,7 @@ class raw_hash_set {
     alignas(slot_type) unsigned char raw[sizeof(slot_type)];
     slot_type* slot = reinterpret_cast<slot_type*>(&raw);
 
-    PolicyTraits::construct(&alloc_ref(), slot, std::forward<Args>(args)...);
+    construct(slot, std::forward<Args>(args)...);
     const auto& elem = PolicyTraits::element(slot);
     return PolicyTraits::apply(InsertSlot<true>{*this, std::move(*slot)}, elem);
   }
@@ -2179,8 +2538,8 @@ class raw_hash_set {
   // This overload is necessary because otherwise erase<K>(const K&) would be
   // a better match if non-const iterator is passed as an argument.
   void erase(iterator it) {
-    AssertIsFull(it.ctrl_, it.generation(), it.generation_ptr(), "erase()");
-    PolicyTraits::destroy(&alloc_ref(), it.slot_);
+    AssertIsFull(it.control(), it.generation(), it.generation_ptr(), "erase()");
+    destroy(it.slot());
     erase_meta_only(it);
   }
 
@@ -2211,8 +2570,8 @@ class raw_hash_set {
     assert(this != &src);
     for (auto it = src.begin(), e = src.end(); it != e;) {
       auto next = std::next(it);
-      if (PolicyTraits::apply(InsertSlot<false>{*this, std::move(*it.slot_)},
-                              PolicyTraits::element(it.slot_))
+      if (PolicyTraits::apply(InsertSlot<false>{*this, std::move(*it.slot())},
+                              PolicyTraits::element(it.slot()))
               .second) {
         src.erase_meta_only(it);
       }
@@ -2226,10 +2585,9 @@ class raw_hash_set {
   }
 
   node_type extract(const_iterator position) {
-    AssertIsFull(position.inner_.ctrl_, position.inner_.generation(),
+    AssertIsFull(position.control(), position.inner_.generation(),
                  position.inner_.generation_ptr(), "extract()");
-    auto node =
-        CommonAccess::Transfer<node_type>(alloc_ref(), position.inner_.slot_);
+    auto node = CommonAccess::Transfer<node_type>(alloc_ref(), position.slot());
     erase_meta_only(position);
     return node;
   }
@@ -2364,7 +2722,11 @@ class raw_hash_set {
 
   template <class K = key_type>
   bool contains(const key_arg<K>& key) const {
-    return find(key) != end();
+    // Here neither the iterator returned by `find()` nor `end()` can be invalid
+    // outside of potential thread-safety issues.
+    // `find()`'s return value is constructed, used, and then destructed
+    // all in this context.
+    return !find(key).unchecked_equals(end());
   }
 
   template <class K = key_type>
@@ -2400,8 +2762,10 @@ class raw_hash_set {
     const raw_hash_set* outer = &a;
     const raw_hash_set* inner = &b;
     if (outer->capacity() > inner->capacity()) std::swap(outer, inner);
-    for (const value_type& elem : *outer)
-      if (!inner->has_element(elem)) return false;
+    for (const value_type& elem : *outer) {
+      auto it = PolicyTraits::apply(FindElement{*inner}, elem);
+      if (it == inner->end() || !(*it == elem)) return false;
+    }
     return true;
   }
 
@@ -2471,10 +2835,9 @@ class raw_hash_set {
     std::pair<iterator, bool> operator()(const K& key, Args&&...) && {
       auto res = s.find_or_prepare_insert(key);
       if (res.second) {
-        PolicyTraits::transfer(&s.alloc_ref(), s.slot_array() + res.first,
-                               &slot);
+        s.transfer(s.slot_array() + res.first, &slot);
       } else if (do_destroy) {
-        PolicyTraits::destroy(&s.alloc_ref(), &slot);
+        s.destroy(&slot);
       }
       return {s.iterator_at(res.first), res.second};
     }
@@ -2483,58 +2846,111 @@ class raw_hash_set {
     slot_type&& slot;
   };
 
+  // TODO(b/303305702): re-enable reentrant validation.
+  template <typename... Args>
+  inline void construct(slot_type* slot, Args&&... args) {
+    PolicyTraits::construct(&alloc_ref(), slot, std::forward<Args>(args)...);
+  }
+  inline void destroy(slot_type* slot) {
+    PolicyTraits::destroy(&alloc_ref(), slot);
+  }
+  inline void transfer(slot_type* to, slot_type* from) {
+    PolicyTraits::transfer(&alloc_ref(), to, from);
+  }
+
+  inline void destroy_slots() {
+    const size_t cap = capacity();
+    const ctrl_t* ctrl = control();
+    slot_type* slot = slot_array();
+    for (size_t i = 0; i != cap; ++i) {
+      if (IsFull(ctrl[i])) {
+        destroy(slot + i);
+      }
+    }
+  }
+
+  inline void dealloc() {
+    assert(capacity() != 0);
+    // Unpoison before returning the memory to the allocator.
+    SanitizerUnpoisonMemoryRegion(slot_array(), sizeof(slot_type) * capacity());
+    infoz().Unregister();
+    Deallocate<BackingArrayAlignment(alignof(slot_type))>(
+        &alloc_ref(), common().backing_array_start(),
+        common().alloc_size(sizeof(slot_type), alignof(slot_type)));
+  }
+
+  inline void destructor_impl() {
+    if (capacity() == 0) return;
+    destroy_slots();
+    dealloc();
+  }
+
   // Erases, but does not destroy, the value pointed to by `it`.
   //
   // This merely updates the pertinent control byte. This can be used in
   // conjunction with Policy::transfer to move the object to another place.
   void erase_meta_only(const_iterator it) {
-    EraseMetaOnly(common(), it.inner_.ctrl_, sizeof(slot_type));
+    EraseMetaOnly(common(), static_cast<size_t>(it.control() - control()),
+                  sizeof(slot_type));
   }
 
-  // Allocates a backing array for `self` and initializes its control bytes.
-  // This reads `capacity` and updates all other fields based on the result of
-  // the allocation.
+  // Resizes table to the new capacity and move all elements to the new
+  // positions accordingly.
   //
-  // This does not free the currently held array; `capacity` must be nonzero.
-  inline void initialize_slots() {
-    // People are often sloppy with the exact type of their allocator (sometimes
-    // it has an extra const or is missing the pair, but rebinds made it work
-    // anyway).
-    using CharAlloc =
-        typename absl::allocator_traits<Alloc>::template rebind_alloc<char>;
-    InitializeSlots<CharAlloc, sizeof(slot_type), alignof(slot_type)>(
-        common(), CharAlloc(alloc_ref()));
-  }
-
+  // Note that for better performance instead of
+  // find_first_non_full(common(), hash),
+  // HashSetResizeHelper::FindFirstNonFullAfterResize(
+  //    common(), old_capacity, hash)
+  // can be called right after `resize`.
   ABSL_ATTRIBUTE_NOINLINE void resize(size_t new_capacity) {
     assert(IsValidCapacity(new_capacity));
-    auto* old_ctrl = control();
+    HashSetResizeHelper resize_helper(common());
     auto* old_slots = slot_array();
-    const size_t old_capacity = common().capacity();
     common().set_capacity(new_capacity);
-    initialize_slots();
-
-    auto* new_slots = slot_array();
-    size_t total_probe_length = 0;
-    for (size_t i = 0; i != old_capacity; ++i) {
-      if (IsFull(old_ctrl[i])) {
-        size_t hash = PolicyTraits::apply(HashElement{hash_ref()},
-                                          PolicyTraits::element(old_slots + i));
-        auto target = find_first_non_full(common(), hash);
-        size_t new_i = target.offset;
-        total_probe_length += target.probe_length;
-        SetCtrl(common(), new_i, H2(hash), sizeof(slot_type));
-        PolicyTraits::transfer(&alloc_ref(), new_slots + new_i, old_slots + i);
-      }
+    // Note that `InitializeSlots` does different number initialization steps
+    // depending on the values of `transfer_uses_memcpy` and capacities.
+    // Refer to the comment in `InitializeSlots` for more details.
+    const bool grow_single_group =
+        resize_helper.InitializeSlots<CharAlloc, sizeof(slot_type),
+                                      PolicyTraits::transfer_uses_memcpy(),
+                                      alignof(slot_type)>(
+            common(), const_cast<std::remove_const_t<slot_type>*>(old_slots),
+            CharAlloc(alloc_ref()));
+
+    if (resize_helper.old_capacity() == 0) {
+      // InitializeSlots did all the work including infoz().RecordRehash().
+      return;
     }
-    if (old_capacity) {
-      SanitizerUnpoisonMemoryRegion(old_slots,
-                                    sizeof(slot_type) * old_capacity);
-      Deallocate<BackingArrayAlignment(alignof(slot_type))>(
-          &alloc_ref(), old_ctrl - ControlOffset(),
-          AllocSize(old_capacity, sizeof(slot_type), alignof(slot_type)));
+
+    if (grow_single_group) {
+      if (PolicyTraits::transfer_uses_memcpy()) {
+        // InitializeSlots did all the work.
+        return;
+      }
+      // We want GrowSizeIntoSingleGroup to be called here in order to make
+      // InitializeSlots not depend on PolicyTraits.
+      resize_helper.GrowSizeIntoSingleGroup<PolicyTraits>(common(), alloc_ref(),
+                                                          old_slots);
+    } else {
+      // InitializeSlots prepares control bytes to correspond to empty table.
+      auto* new_slots = slot_array();
+      size_t total_probe_length = 0;
+      for (size_t i = 0; i != resize_helper.old_capacity(); ++i) {
+        if (IsFull(resize_helper.old_ctrl()[i])) {
+          size_t hash = PolicyTraits::apply(
+              HashElement{hash_ref()}, PolicyTraits::element(old_slots + i));
+          auto target = find_first_non_full(common(), hash);
+          size_t new_i = target.offset;
+          total_probe_length += target.probe_length;
+          SetCtrl(common(), new_i, H2(hash), sizeof(slot_type));
+          transfer(new_slots + new_i, old_slots + i);
+        }
+      }
+      infoz().RecordRehash(total_probe_length);
     }
-    infoz().RecordRehash(total_probe_length);
+    resize_helper.DeallocateOld<alignof(slot_type)>(
+        CharAlloc(alloc_ref()), sizeof(slot_type),
+        const_cast<std::remove_const_t<slot_type>*>(old_slots));
   }
 
   // Prunes control bytes to remove as many tombstones as possible.
@@ -2604,36 +3020,64 @@ class raw_hash_set {
     }
   }
 
-  bool has_element(const value_type& elem) const {
-    size_t hash = PolicyTraits::apply(HashElement{hash_ref()}, elem);
-    auto seq = probe(common(), hash);
-    const ctrl_t* ctrl = control();
-    while (true) {
-      Group g{ctrl + seq.offset()};
-      for (uint32_t i : g.Match(H2(hash))) {
-        if (ABSL_PREDICT_TRUE(
-                PolicyTraits::element(slot_array() + seq.offset(i)) == elem))
-          return true;
-      }
-      if (ABSL_PREDICT_TRUE(g.MaskEmpty())) return false;
-      seq.next();
-      assert(seq.index() <= capacity() && "full table!");
+  void maybe_increment_generation_or_rehash_on_move() {
+    common().maybe_increment_generation_on_move();
+    if (!empty() && common().should_rehash_for_bug_detection_on_move()) {
+      resize(capacity());
     }
-    return false;
   }
 
-  // TODO(alkis): Optimize this assuming *this and that don't overlap.
-  raw_hash_set& move_assign(raw_hash_set&& that, std::true_type) {
-    raw_hash_set tmp(std::move(that));
-    swap(tmp);
+  template<bool propagate_alloc>
+  raw_hash_set& assign_impl(raw_hash_set&& that) {
+    // We don't bother checking for this/that aliasing. We just need to avoid
+    // breaking the invariants in that case.
+    destructor_impl();
+    common() = std::move(that.common());
+    // TODO(b/296061262): move instead of copying hash/eq/alloc.
+    hash_ref() = that.hash_ref();
+    eq_ref() = that.eq_ref();
+    CopyAlloc(alloc_ref(), that.alloc_ref(),
+              std::integral_constant<bool, propagate_alloc>());
+    that.common() = CommonFields{};
+    maybe_increment_generation_or_rehash_on_move();
     return *this;
   }
-  raw_hash_set& move_assign(raw_hash_set&& that, std::false_type) {
-    raw_hash_set tmp(std::move(that), alloc_ref());
-    swap(tmp);
+
+  raw_hash_set& move_elements_allocs_unequal(raw_hash_set&& that) {
+    const size_t size = that.size();
+    if (size == 0) return *this;
+    reserve(size);
+    for (iterator it = that.begin(); it != that.end(); ++it) {
+      insert(std::move(PolicyTraits::element(it.slot())));
+      that.destroy(it.slot());
+    }
+    that.dealloc();
+    that.common() = CommonFields{};
+    maybe_increment_generation_or_rehash_on_move();
     return *this;
   }
 
+  raw_hash_set& move_assign(raw_hash_set&& that,
+                            std::true_type /*propagate_alloc*/) {
+    return assign_impl<true>(std::move(that));
+  }
+  raw_hash_set& move_assign(raw_hash_set&& that,
+                            std::false_type /*propagate_alloc*/) {
+    if (alloc_ref() == that.alloc_ref()) {
+      return assign_impl<false>(std::move(that));
+    }
+    // Aliasing can't happen here because allocs would compare equal above.
+    assert(this != &that);
+    destructor_impl();
+    // We can't take over that's memory so we need to move each element.
+    // While moving elements, this should have that's hash/eq so copy hash/eq
+    // before moving elements.
+    // TODO(b/296061262): move instead of copying hash/eq.
+    hash_ref() = that.hash_ref();
+    eq_ref() = that.eq_ref();
+    return move_elements_allocs_unequal(std::move(that));
+  }
+
  protected:
   // Attempts to find `key` in the table; if it isn't found, returns a slot that
   // the value can be inserted into, with the control byte already set to
@@ -2675,10 +3119,19 @@ class raw_hash_set {
     if (!rehash_for_bug_detection &&
         ABSL_PREDICT_FALSE(growth_left() == 0 &&
                            !IsDeleted(control()[target.offset]))) {
+      size_t old_capacity = capacity();
       rehash_and_grow_if_necessary();
-      target = find_first_non_full(common(), hash);
+      // NOTE: It is safe to use `FindFirstNonFullAfterResize`.
+      // `FindFirstNonFullAfterResize` must be called right after resize.
+      // `rehash_and_grow_if_necessary` may *not* call `resize`
+      // and perform `drop_deletes_without_resize` instead. But this
+      // could happen only on big tables.
+      // For big tables `FindFirstNonFullAfterResize` will always
+      // fallback to normal `find_first_non_full`, so it is safe to use it.
+      target = HashSetResizeHelper::FindFirstNonFullAfterResize(
+          common(), old_capacity, hash);
     }
-    common().set_size(common().size() + 1);
+    common().increment_size();
     set_growth_left(growth_left() - IsEmpty(control()[target.offset]));
     SetCtrl(common(), target.offset, H2(hash), sizeof(slot_type));
     common().maybe_increment_generation_on_insert();
@@ -2696,8 +3149,7 @@ class raw_hash_set {
   // POSTCONDITION: *m.iterator_at(i) == value_type(forward<Args>(args)...).
   template <class... Args>
   void emplace_at(size_t i, Args&&... args) {
-    PolicyTraits::construct(&alloc_ref(), slot_array() + i,
-                            std::forward<Args>(args)...);
+    construct(slot_array() + i, std::forward<Args>(args)...);
 
     assert(PolicyTraits::apply(FindElement{*this}, *iterator_at(i)) ==
                iterator_at(i) &&
@@ -2711,6 +3163,8 @@ class raw_hash_set {
     return {control() + i, slot_array() + i, common().generation_ptr()};
   }
 
+  reference unchecked_deref(iterator it) { return it.unchecked_deref(); }
+
  private:
   friend struct RawHashSetTestOnlyAccess;
 
@@ -2743,7 +3197,7 @@ class raw_hash_set {
   slot_type* slot_array() const {
     return static_cast<slot_type*>(common().slot_array());
   }
-  HashtablezInfoHandle& infoz() { return common().infoz(); }
+  HashtablezInfoHandle infoz() { return common().infoz(); }
 
   hasher& hash_ref() { return settings_.template get<1>(); }
   const hasher& hash_ref() const { return settings_.template get<1>(); }
@@ -2763,8 +3217,7 @@ class raw_hash_set {
   }
   static void transfer_slot_fn(void* set, void* dst, void* src) {
     auto* h = static_cast<raw_hash_set*>(set);
-    PolicyTraits::transfer(&h->alloc_ref(), static_cast<slot_type*>(dst),
-                           static_cast<slot_type*>(src));
+    h->transfer(static_cast<slot_type*>(dst), static_cast<slot_type*>(src));
   }
   // Note: dealloc_fn will only be used if we have a non-standard allocator.
   static void dealloc_fn(CommonFields& common, const PolicyFunctions&) {
@@ -2774,6 +3227,7 @@ class raw_hash_set {
     SanitizerUnpoisonMemoryRegion(common.slot_array(),
                                   sizeof(slot_type) * common.capacity());
 
+    common.infoz().Unregister();
     Deallocate<BackingArrayAlignment(alignof(slot_type))>(
         &set->alloc_ref(), common.backing_array_start(),
         common.alloc_size(sizeof(slot_type), alignof(slot_type)));
@@ -2847,33 +3301,18 @@ struct HashtableDebugAccess<Set, absl::void_t<typename Set::raw_hash_set>> {
   static size_t AllocatedByteSize(const Set& c) {
     size_t capacity = c.capacity();
     if (capacity == 0) return 0;
-    size_t m = AllocSize(capacity, sizeof(Slot), alignof(Slot));
+    size_t m = c.common().alloc_size(sizeof(Slot), alignof(Slot));
 
     size_t per_slot = Traits::space_used(static_cast<const Slot*>(nullptr));
     if (per_slot != ~size_t{}) {
       m += per_slot * c.size();
     } else {
-      const ctrl_t* ctrl = c.control();
-      for (size_t i = 0; i != capacity; ++i) {
-        if (container_internal::IsFull(ctrl[i])) {
-          m += Traits::space_used(c.slot_array() + i);
-        }
+      for (auto it = c.begin(); it != c.end(); ++it) {
+        m += Traits::space_used(it.slot());
       }
     }
     return m;
   }
-
-  static size_t LowerBoundAllocatedByteSize(size_t size) {
-    size_t capacity = GrowthToLowerboundCapacity(size);
-    if (capacity == 0) return 0;
-    size_t m =
-        AllocSize(NormalizeCapacity(capacity), sizeof(Slot), alignof(Slot));
-    size_t per_slot = Traits::space_used(static_cast<const Slot*>(nullptr));
-    if (per_slot != ~size_t{}) {
-      m += per_slot * size;
-    }
-    return m;
-  }
 };
 
 }  // namespace hashtable_debug_internal
diff --git a/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.cc b/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.cc
index 838380854f..d7eedd1ca4 100644
--- a/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.cc
+++ b/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.cc
@@ -189,8 +189,14 @@ CpuType GetAmdCpuType() {
       break;
     case 0x19:
       switch (model_num) {
+        case 0x0:  // Stepping Ax
         case 0x1:  // Stepping B0
           return CpuType::kAmdMilan;
+        case 0x10:  // Stepping A0
+        case 0x11:  // Stepping B0
+          return CpuType::kAmdGenoa;
+        case 0x44:  // Stepping A0
+          return CpuType::kAmdRyzenV3000;
         default:
           return CpuType::kUnknown;
       }
@@ -237,8 +243,26 @@ CpuType GetCpuType() {
     ABSL_INTERNAL_AARCH64_ID_REG_READ(MIDR_EL1, midr);
     uint32_t implementer = (midr >> 24) & 0xff;
     uint32_t part_number = (midr >> 4) & 0xfff;
-    if (implementer == 0x41 && part_number == 0xd0c) {
-      return CpuType::kArmNeoverseN1;
+    switch (implementer) {
+      case 0x41:
+        switch (part_number) {
+          case 0xd0c: return CpuType::kArmNeoverseN1;
+          case 0xd40: return CpuType::kArmNeoverseV1;
+          case 0xd49: return CpuType::kArmNeoverseN2;
+          case 0xd4f: return CpuType::kArmNeoverseV2;
+          default:
+            return CpuType::kUnknown;
+        }
+        break;
+      case 0xc0:
+        switch (part_number) {
+          case 0xac3: return CpuType::kAmpereSiryn;
+          default:
+            return CpuType::kUnknown;
+        }
+        break;
+      default:
+        return CpuType::kUnknown;
     }
   }
   return CpuType::kUnknown;
diff --git a/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.h b/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.h
index 6054f6960d..01e19590ca 100644
--- a/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.h
+++ b/contrib/restricted/abseil-cpp/absl/crc/internal/cpu_detect.h
@@ -29,6 +29,8 @@ enum class CpuType {
   kAmdRome,
   kAmdNaples,
   kAmdMilan,
+  kAmdGenoa,
+  kAmdRyzenV3000,
   kIntelCascadelakeXeon,
   kIntelSkylakeXeon,
   kIntelBroadwell,
@@ -37,6 +39,10 @@ enum class CpuType {
   kIntelSandybridge,
   kIntelWestmere,
   kArmNeoverseN1,
+  kArmNeoverseV1,
+  kAmpereSiryn,
+  kArmNeoverseN2,
+  kArmNeoverseV2
 };
 
 // Returns the type of host CPU this code is running on.  Returns kUnknown if
diff --git a/contrib/restricted/abseil-cpp/absl/crc/internal/crc32_x86_arm_combined_simd.h b/contrib/restricted/abseil-cpp/absl/crc/internal/crc32_x86_arm_combined_simd.h
index 39e53dd08e..59995ae3e2 100644
--- a/contrib/restricted/abseil-cpp/absl/crc/internal/crc32_x86_arm_combined_simd.h
+++ b/contrib/restricted/abseil-cpp/absl/crc/internal/crc32_x86_arm_combined_simd.h
@@ -59,6 +59,8 @@ namespace crc_internal {
 #if defined(ABSL_CRC_INTERNAL_HAVE_ARM_SIMD)
 using V128 = uint64x2_t;
 #else
+// Note: Do not use __m128i_u, it is not portable.
+// Use V128_LoadU() perform an unaligned load from __m128i*.
 using V128 = __m128i;
 #endif
 
@@ -78,6 +80,9 @@ V128 V128_Load(const V128* src);
 // Load 128 bits of integer data. |src| does not need to be aligned.
 V128 V128_LoadU(const V128* src);
 
+// Store 128 bits of integer data. |src| must be 16-byte aligned.
+void V128_Store(V128* dst, V128 data);
+
 // Polynomially multiplies the high 64 bits of |l| and |r|.
 V128 V128_PMulHi(const V128 l, const V128 r);
 
@@ -109,6 +114,10 @@ V128 V128_ShiftRight(const V128 l);
 template <int imm>
 int V128_Extract32(const V128 l);
 
+// Extracts a 64-bit integer from |l|, selected with |imm|.
+template <int imm>
+uint64_t V128_Extract64(const V128 l);
+
 // Extracts the low 64 bits from V128.
 int64_t V128_Low64(const V128 l);
 
@@ -139,6 +148,8 @@ inline V128 V128_Load(const V128* src) { return _mm_load_si128(src); }
 
 inline V128 V128_LoadU(const V128* src) { return _mm_loadu_si128(src); }
 
+inline void V128_Store(V128* dst, V128 data) { _mm_store_si128(dst, data); }
+
 inline V128 V128_PMulHi(const V128 l, const V128 r) {
   return _mm_clmulepi64_si128(l, r, 0x11);
 }
@@ -173,6 +184,11 @@ inline int V128_Extract32(const V128 l) {
   return _mm_extract_epi32(l, imm);
 }
 
+template <int imm>
+inline uint64_t V128_Extract64(const V128 l) {
+  return static_cast<uint64_t>(_mm_extract_epi64(l, imm));
+}
+
 inline int64_t V128_Low64(const V128 l) { return _mm_cvtsi128_si64(l); }
 
 inline V128 V128_ShiftLeft64(const V128 l, const V128 r) {
@@ -203,10 +219,14 @@ inline V128 V128_LoadU(const V128* src) {
   return vld1q_u64(reinterpret_cast<const uint64_t*>(src));
 }
 
+inline void V128_Store(V128* dst, V128 data) {
+  vst1q_u64(reinterpret_cast<uint64_t*>(dst), data);
+}
+
 // Using inline assembly as clang does not generate the pmull2 instruction and
 // performance drops by 15-20%.
-// TODO(b/193678732): Investigate why the compiler decides not to generate
-// such instructions and why it becomes so much worse.
+// TODO(b/193678732): Investigate why there is a slight performance hit when
+// using intrinsics instead of inline assembly.
 inline V128 V128_PMulHi(const V128 l, const V128 r) {
   uint64x2_t res;
   __asm__ __volatile__("pmull2 %0.1q, %1.2d, %2.2d \n\t"
@@ -215,10 +235,14 @@ inline V128 V128_PMulHi(const V128 l, const V128 r) {
   return res;
 }
 
+// TODO(b/193678732): Investigate why the compiler decides to move the constant
+// loop multiplicands from GPR to Neon registers every loop iteration.
 inline V128 V128_PMulLow(const V128 l, const V128 r) {
-  return reinterpret_cast<V128>(vmull_p64(
-      reinterpret_cast<poly64_t>(vget_low_p64(vreinterpretq_p64_u64(l))),
-      reinterpret_cast<poly64_t>(vget_low_p64(vreinterpretq_p64_u64(r)))));
+  uint64x2_t res;
+  __asm__ __volatile__("pmull %0.1q, %1.1d, %2.1d \n\t"
+                       : "=w"(res)
+                       : "w"(l), "w"(r));
+  return res;
 }
 
 inline V128 V128_PMul01(const V128 l, const V128 r) {
@@ -252,6 +276,11 @@ inline int V128_Extract32(const V128 l) {
   return vgetq_lane_s32(vreinterpretq_s32_u64(l), imm);
 }
 
+template <int imm>
+inline uint64_t V128_Extract64(const V128 l) {
+  return vgetq_lane_u64(l, imm);
+}
+
 inline int64_t V128_Low64(const V128 l) {
   return vgetq_lane_s64(vreinterpretq_s64_u64(l), 0);
 }
diff --git a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy.h b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy.h
index 4909d43366..a0fed65afa 100644
--- a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy.h
+++ b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy.h
@@ -20,12 +20,15 @@
 
 #include "absl/base/config.h"
 #include "absl/crc/crc32c.h"
+#include "absl/crc/internal/crc32_x86_arm_combined_simd.h"
 
 // Defined if the class AcceleratedCrcMemcpyEngine exists.
-#if defined(__x86_64__) && defined(__SSE4_2__)
-#define ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE 1
-#elif defined(_MSC_VER) && defined(__AVX__)
+// TODO(b/299127771): Consider relaxing the pclmul requirement once the other
+// intrinsics are conditionally compiled without it.
+#if defined(ABSL_CRC_INTERNAL_HAVE_X86_SIMD)
 #define ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE 1
+#elif defined(ABSL_CRC_INTERNAL_HAVE_ARM_SIMD)
+#define ABSL_INTERNAL_HAVE_ARM_ACCELERATED_CRC_MEMCPY_ENGINE 1
 #endif
 
 namespace absl {
diff --git a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_fallback.cc b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_fallback.cc
index 15b4b05594..07795504e3 100644
--- a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_fallback.cc
+++ b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_fallback.cc
@@ -54,7 +54,8 @@ absl::crc32c_t FallbackCrcMemcpyEngine::Compute(void* __restrict dst,
 }
 
 // Compile the following only if we don't have
-#ifndef ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE
+#if !defined(ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE) && \
+    !defined(ABSL_INTERNAL_HAVE_ARM_ACCELERATED_CRC_MEMCPY_ENGINE)
 
 CrcMemcpy::ArchSpecificEngines CrcMemcpy::GetArchSpecificEngines() {
   CrcMemcpy::ArchSpecificEngines engines;
@@ -68,7 +69,8 @@ std::unique_ptr<CrcMemcpyEngine> CrcMemcpy::GetTestEngine(int /*vector*/,
   return std::make_unique<FallbackCrcMemcpyEngine>();
 }
 
-#endif  // ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE
+#endif  // !ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE &&
+        // !ABSL_INTERNAL_HAVE_ARM_ACCELERATED_CRC_MEMCPY_ENGINE
 
 }  // namespace crc_internal
 ABSL_NAMESPACE_END
diff --git a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_x86_64.cc b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_x86_arm_combined.cc
index d42b08dc9f..968e9ae359 100644
--- a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_x86_64.cc
+++ b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_memcpy_x86_arm_combined.cc
@@ -12,9 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Simultaneous memcopy and CRC-32C for x86-64.  Uses integer registers because
-// XMM registers do not support the CRC instruction (yet).  While copying,
-// compute the running CRC of the data being copied.
+// Simultaneous memcopy and CRC-32C for x86-64 and ARM 64. Uses integer
+// registers because XMM registers do not support the CRC instruction (yet).
+// While copying, compute the running CRC of the data being copied.
 //
 // It is assumed that any CPU running this code has SSE4.2 instructions
 // available (for CRC32C).  This file will do nothing if that is not true.
@@ -49,17 +49,20 @@
 #include <array>
 #include <cstddef>
 #include <cstdint>
-#include <type_traits>
+#include <cstring>
+#include <memory>
 
-#include "absl/base/dynamic_annotations.h"
+#include "absl/base/config.h"
 #include "absl/base/optimization.h"
 #include "absl/base/prefetch.h"
 #include "absl/crc/crc32c.h"
 #include "absl/crc/internal/cpu_detect.h"
+#include "absl/crc/internal/crc32_x86_arm_combined_simd.h"
 #include "absl/crc/internal/crc_memcpy.h"
 #include "absl/strings/string_view.h"
 
-#ifdef ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE
+#if defined(ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE) || \
+    defined(ABSL_INTERNAL_HAVE_ARM_ACCELERATED_CRC_MEMCPY_ENGINE)
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -74,7 +77,7 @@ inline crc32c_t ShortCrcCopy(char* dst, const char* src, std::size_t length,
   uint32_t crc_uint32 = static_cast<uint32_t>(crc);
   for (std::size_t i = 0; i < length; i++) {
     uint8_t data = *reinterpret_cast<const uint8_t*>(src);
-    crc_uint32 = _mm_crc32_u8(crc_uint32, data);
+    crc_uint32 = CRC32_u8(crc_uint32, data);
     *reinterpret_cast<uint8_t*>(dst) = data;
     ++src;
     ++dst;
@@ -82,36 +85,35 @@ inline crc32c_t ShortCrcCopy(char* dst, const char* src, std::size_t length,
   return crc32c_t{crc_uint32};
 }
 
-constexpr size_t kIntLoadsPerVec = sizeof(__m128i) / sizeof(uint64_t);
+constexpr size_t kIntLoadsPerVec = sizeof(V128) / sizeof(uint64_t);
 
 // Common function for copying the tails of multiple large regions.
 template <size_t vec_regions, size_t int_regions>
 inline void LargeTailCopy(crc32c_t* crcs, char** dst, const char** src,
                           size_t region_size, size_t copy_rounds) {
-  std::array<__m128i, vec_regions> data;
+  std::array<V128, vec_regions> data;
   std::array<uint64_t, kIntLoadsPerVec * int_regions> int_data;
 
   while (copy_rounds > 0) {
     for (size_t i = 0; i < vec_regions; i++) {
       size_t region = i;
 
-      auto* vsrc =
-          reinterpret_cast<const __m128i*>(*src + region_size * region);
-      auto* vdst = reinterpret_cast<__m128i*>(*dst + region_size * region);
+      auto* vsrc = reinterpret_cast<const V128*>(*src + region_size * region);
+      auto* vdst = reinterpret_cast<V128*>(*dst + region_size * region);
 
       // Load the blocks, unaligned
-      data[i] = _mm_loadu_si128(vsrc);
+      data[i] = V128_LoadU(vsrc);
 
       // Store the blocks, aligned
-      _mm_store_si128(vdst, data[i]);
+      V128_Store(vdst, data[i]);
 
       // Compute the running CRC
       crcs[region] = crc32c_t{static_cast<uint32_t>(
-          _mm_crc32_u64(static_cast<uint32_t>(crcs[region]),
-                        static_cast<uint64_t>(_mm_extract_epi64(data[i], 0))))};
+          CRC32_u64(static_cast<uint32_t>(crcs[region]),
+                    static_cast<uint64_t>(V128_Extract64<0>(data[i]))))};
       crcs[region] = crc32c_t{static_cast<uint32_t>(
-          _mm_crc32_u64(static_cast<uint32_t>(crcs[region]),
-                        static_cast<uint64_t>(_mm_extract_epi64(data[i], 1))))};
+          CRC32_u64(static_cast<uint32_t>(crcs[region]),
+                    static_cast<uint64_t>(V128_Extract64<1>(data[i]))))};
     }
 
     for (size_t i = 0; i < int_regions; i++) {
@@ -125,7 +127,7 @@ inline void LargeTailCopy(crc32c_t* crcs, char** dst, const char** src,
         size_t data_index = i * kIntLoadsPerVec + j;
 
         int_data[data_index] = *(usrc + j);
-        crcs[region] = crc32c_t{static_cast<uint32_t>(_mm_crc32_u64(
+        crcs[region] = crc32c_t{static_cast<uint32_t>(CRC32_u64(
             static_cast<uint32_t>(crcs[region]), int_data[data_index]))};
 
         *(udst + j) = int_data[data_index];
@@ -133,8 +135,8 @@ inline void LargeTailCopy(crc32c_t* crcs, char** dst, const char** src,
     }
 
     // Increment pointers
-    *src += sizeof(__m128i);
-    *dst += sizeof(__m128i);
+    *src += sizeof(V128);
+    *dst += sizeof(V128);
     --copy_rounds;
   }
 }
@@ -158,8 +160,9 @@ crc32c_t AcceleratedCrcMemcpyEngine<vec_regions, int_regions>::Compute(
     void* __restrict dst, const void* __restrict src, std::size_t length,
     crc32c_t initial_crc) const {
   constexpr std::size_t kRegions = vec_regions + int_regions;
+  static_assert(kRegions > 0, "Must specify at least one region.");
   constexpr uint32_t kCrcDataXor = uint32_t{0xffffffff};
-  constexpr std::size_t kBlockSize = sizeof(__m128i);
+  constexpr std::size_t kBlockSize = sizeof(V128);
   constexpr std::size_t kCopyRoundSize = kRegions * kBlockSize;
 
   // Number of blocks per cacheline.
@@ -235,7 +238,7 @@ crc32c_t AcceleratedCrcMemcpyEngine<vec_regions, int_regions>::Compute(
   const std::size_t tail_size = length - (kRegions * region_size);
 
   // Holding registers for data in each region.
-  std::array<__m128i, vec_regions> vec_data;
+  std::array<V128, vec_regions> vec_data;
   std::array<uint64_t, int_regions * kIntLoadsPerVec> int_data;
 
   // Main loop.
@@ -243,7 +246,10 @@ crc32c_t AcceleratedCrcMemcpyEngine<vec_regions, int_regions>::Compute(
     // Prefetch kPrefetchAhead bytes ahead of each pointer.
     for (size_t i = 0; i < kRegions; i++) {
       absl::PrefetchToLocalCache(src_bytes + kPrefetchAhead + region_size * i);
+#ifdef ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE
+      // TODO(b/297082454): investigate dropping prefetch on x86.
       absl::PrefetchToLocalCache(dst_bytes + kPrefetchAhead + region_size * i);
+#endif
     }
 
     // Load and store data, computing CRC on the way.
@@ -256,21 +262,20 @@ crc32c_t AcceleratedCrcMemcpyEngine<vec_regions, int_regions>::Compute(
         size_t region = (j + i) % kRegions;
 
         auto* vsrc =
-            reinterpret_cast<const __m128i*>(src_bytes + region_size * region);
-        auto* vdst =
-            reinterpret_cast<__m128i*>(dst_bytes + region_size * region);
+            reinterpret_cast<const V128*>(src_bytes + region_size * region);
+        auto* vdst = reinterpret_cast<V128*>(dst_bytes + region_size * region);
 
         // Load and CRC data.
-        vec_data[j] = _mm_loadu_si128(vsrc + i);
-        crcs[region] = crc32c_t{static_cast<uint32_t>(_mm_crc32_u64(
-            static_cast<uint32_t>(crcs[region]),
-            static_cast<uint64_t>(_mm_extract_epi64(vec_data[j], 0))))};
-        crcs[region] = crc32c_t{static_cast<uint32_t>(_mm_crc32_u64(
-            static_cast<uint32_t>(crcs[region]),
-            static_cast<uint64_t>(_mm_extract_epi64(vec_data[j], 1))))};
+        vec_data[j] = V128_LoadU(vsrc + i);
+        crcs[region] = crc32c_t{static_cast<uint32_t>(
+            CRC32_u64(static_cast<uint32_t>(crcs[region]),
+                      static_cast<uint64_t>(V128_Extract64<0>(vec_data[j]))))};
+        crcs[region] = crc32c_t{static_cast<uint32_t>(
+            CRC32_u64(static_cast<uint32_t>(crcs[region]),
+                      static_cast<uint64_t>(V128_Extract64<1>(vec_data[j]))))};
 
         // Store the data.
-        _mm_store_si128(vdst + i, vec_data[j]);
+        V128_Store(vdst + i, vec_data[j]);
       }
 
       // Preload the partial CRCs for the CLMUL subregions.
@@ -290,7 +295,7 @@ crc32c_t AcceleratedCrcMemcpyEngine<vec_regions, int_regions>::Compute(
 
           // Load and CRC the data.
           int_data[data_index] = *(usrc + i * kIntLoadsPerVec + k);
-          crcs[region] = crc32c_t{static_cast<uint32_t>(_mm_crc32_u64(
+          crcs[region] = crc32c_t{static_cast<uint32_t>(CRC32_u64(
               static_cast<uint32_t>(crcs[region]), int_data[data_index]))};
 
           // Store the data.
@@ -313,6 +318,21 @@ crc32c_t AcceleratedCrcMemcpyEngine<vec_regions, int_regions>::Compute(
   src_bytes += region_size * (kRegions - 1);
   dst_bytes += region_size * (kRegions - 1);
 
+  // Copy and CRC the tail through the XMM registers.
+  std::size_t tail_blocks = tail_size / kBlockSize;
+  LargeTailCopy<0, 1>(&crcs[kRegions - 1], &dst_bytes, &src_bytes, 0,
+                      tail_blocks);
+
+  // Final tail copy for under 16 bytes.
+  crcs[kRegions - 1] =
+      ShortCrcCopy(dst_bytes, src_bytes, tail_size - tail_blocks * kBlockSize,
+                   crcs[kRegions - 1]);
+
+  if (kRegions == 1) {
+    // If there is only one region, finalize and return its CRC.
+    return crc32c_t{static_cast<uint32_t>(crcs[0]) ^ kCrcDataXor};
+  }
+
   // Finalize the first CRCs: XOR the internal CRCs by the XOR mask to undo the
   // XOR done before doing block copy + CRCs.
   for (size_t i = 0; i + 1 < kRegions; i++) {
@@ -325,16 +345,6 @@ crc32c_t AcceleratedCrcMemcpyEngine<vec_regions, int_regions>::Compute(
     full_crc = ConcatCrc32c(full_crc, crcs[i], region_size);
   }
 
-  // Copy and CRC the tail through the XMM registers.
-  std::size_t tail_blocks = tail_size / kBlockSize;
-  LargeTailCopy<0, 1>(&crcs[kRegions - 1], &dst_bytes, &src_bytes, 0,
-                      tail_blocks);
-
-  // Final tail copy for under 16 bytes.
-  crcs[kRegions - 1] =
-      ShortCrcCopy(dst_bytes, src_bytes, tail_size - tail_blocks * kBlockSize,
-                   crcs[kRegions - 1]);
-
   // Finalize and concatenate the final CRC, then return.
   crcs[kRegions - 1] =
       crc32c_t{static_cast<uint32_t>(crcs[kRegions - 1]) ^ kCrcDataXor};
@@ -347,9 +357,11 @@ CrcMemcpy::ArchSpecificEngines CrcMemcpy::GetArchSpecificEngines() {
   // Get the underlying architecture.
   CpuType cpu_type = GetCpuType();
   switch (cpu_type) {
-    case CpuType::kUnknown:
     case CpuType::kAmdRome:
     case CpuType::kAmdNaples:
+    case CpuType::kAmdMilan:
+    case CpuType::kAmdGenoa:
+    case CpuType::kAmdRyzenV3000:
     case CpuType::kIntelCascadelakeXeon:
     case CpuType::kIntelSkylakeXeon:
     case CpuType::kIntelSkylake:
@@ -385,6 +397,9 @@ CrcMemcpy::ArchSpecificEngines CrcMemcpy::GetArchSpecificEngines() {
     // strided access to each region, and do the right thing.
     case CpuType::kAmdRome:
     case CpuType::kAmdNaples:
+    case CpuType::kAmdMilan:
+    case CpuType::kAmdGenoa:
+    case CpuType::kAmdRyzenV3000:
       return {
           /*.temporal=*/new AcceleratedCrcMemcpyEngine<1, 2>(),
           /*.non_temporal=*/new CrcNonTemporalMemcpyAVXEngine(),
@@ -421,6 +436,8 @@ std::unique_ptr<CrcMemcpyEngine> CrcMemcpy::GetTestEngine(int vector,
     return std::make_unique<AcceleratedCrcMemcpyEngine<3, 0>>();
   } else if (vector == 1 && integer == 2) {
     return std::make_unique<AcceleratedCrcMemcpyEngine<1, 2>>();
+  } else if (vector == 1 && integer == 0) {
+    return std::make_unique<AcceleratedCrcMemcpyEngine<1, 0>>();
   }
   return nullptr;
 }
@@ -429,4 +446,5 @@ std::unique_ptr<CrcMemcpyEngine> CrcMemcpy::GetTestEngine(int vector,
 ABSL_NAMESPACE_END
 }  // namespace absl
 
-#endif  // ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE
+#endif  // ABSL_INTERNAL_HAVE_X86_64_ACCELERATED_CRC_MEMCPY_ENGINE ||
+        // ABSL_INTERNAL_HAVE_ARM_ACCELERATED_CRC_MEMCPY_ENGINE
diff --git a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_x86_arm_combined.cc b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_x86_arm_combined.cc
index ef521d22d1..51eff4eddc 100644
--- a/contrib/restricted/abseil-cpp/absl/crc/internal/crc_x86_arm_combined.cc
+++ b/contrib/restricted/abseil-cpp/absl/crc/internal/crc_x86_arm_combined.cc
@@ -16,14 +16,14 @@
 
 #include <cstddef>
 #include <cstdint>
+#include <memory>
+#include <vector>
 
 #include "absl/base/attributes.h"
 #include "absl/base/config.h"
-#include "absl/base/dynamic_annotations.h"
 #include "absl/base/internal/endian.h"
 #include "absl/base/prefetch.h"
 #include "absl/crc/internal/cpu_detect.h"
-#include "absl/crc/internal/crc.h"
 #include "absl/crc/internal/crc32_x86_arm_combined_simd.h"
 #include "absl/crc/internal/crc_internal.h"
 #include "absl/memory/memory.h"
@@ -634,8 +634,16 @@ CRCImpl* TryNewCRC32AcceleratedX86ARMCombined() {
       return new CRC32AcceleratedX86ARMCombinedMultipleStreams<
           3, 0, CutoffStrategy::Fold3>();
     case CpuType::kArmNeoverseN1:
+    case CpuType::kArmNeoverseN2:
+    case CpuType::kArmNeoverseV1:
       return new CRC32AcceleratedX86ARMCombinedMultipleStreams<
           1, 1, CutoffStrategy::Unroll64CRC>();
+    case CpuType::kAmpereSiryn:
+      return new CRC32AcceleratedX86ARMCombinedMultipleStreams<
+          3, 2, CutoffStrategy::Fold3>();
+    case CpuType::kArmNeoverseV2:
+      return new CRC32AcceleratedX86ARMCombinedMultipleStreams<
+          1, 2, CutoffStrategy::Unroll64CRC>();
 #if defined(__aarch64__)
     default:
       // Not all ARM processors support the needed instructions, so check here
diff --git a/contrib/restricted/abseil-cpp/absl/debugging/failure_signal_handler.cc b/contrib/restricted/abseil-cpp/absl/debugging/failure_signal_handler.cc
index 992c89c390..570d1e504d 100644
--- a/contrib/restricted/abseil-cpp/absl/debugging/failure_signal_handler.cc
+++ b/contrib/restricted/abseil-cpp/absl/debugging/failure_signal_handler.cc
@@ -54,7 +54,7 @@
 #include "absl/debugging/internal/examine_stack.h"
 #include "absl/debugging/stacktrace.h"
 
-#ifndef _WIN32
+#if !defined(_WIN32) && !defined(__wasi__)
 #define ABSL_HAVE_SIGACTION
 // Apple WatchOS and TVOS don't allow sigaltstack
 // Apple macOS has sigaltstack, but using it makes backtrace() unusable.
diff --git a/contrib/restricted/abseil-cpp/absl/debugging/internal/address_is_readable.cc b/contrib/restricted/abseil-cpp/absl/debugging/internal/address_is_readable.cc
index 91eaa76f8a..be17a10591 100644
--- a/contrib/restricted/abseil-cpp/absl/debugging/internal/address_is_readable.cc
+++ b/contrib/restricted/abseil-cpp/absl/debugging/internal/address_is_readable.cc
@@ -50,8 +50,10 @@ namespace debugging_internal {
 // NOTE: any new system calls here may also require sandbox reconfiguration.
 //
 bool AddressIsReadable(const void *addr) {
-  // Align address on 8-byte boundary. On aarch64, checking last
-  // byte before inaccessible page returned unexpected EFAULT.
+  // rt_sigprocmask below checks 8 contiguous bytes. If addr resides in the
+  // last 7 bytes of a page (unaligned), rt_sigprocmask would additionally
+  // check the readability of the next page, which is not desired. Align
+  // address on 8-byte boundary to check only the current page.
   const uintptr_t u_addr = reinterpret_cast<uintptr_t>(addr) & ~uintptr_t{7};
   addr = reinterpret_cast<const void *>(u_addr);
 
diff --git a/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.cc b/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.cc
index f2832915bf..381a2b504b 100644
--- a/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.cc
+++ b/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.cc
@@ -21,7 +21,15 @@
 
 #include <cstdint>
 #include <cstdio>
+#include <cstdlib>
 #include <limits>
+#include <string>
+
+#include "absl/base/config.h"
+
+#if ABSL_INTERNAL_HAS_CXA_DEMANGLE
+#include <cxxabi.h>
+#endif
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -1983,6 +1991,22 @@ bool Demangle(const char* mangled, char* out, size_t out_size) {
          state.parse_state.out_cur_idx > 0;
 }
 
+std::string DemangleString(const char* mangled) {
+  std::string out;
+  int status = 0;
+  char* demangled = nullptr;
+#if ABSL_INTERNAL_HAS_CXA_DEMANGLE
+  demangled = abi::__cxa_demangle(mangled, nullptr, nullptr, &status);
+#endif
+  if (status == 0 && demangled != nullptr) {
+    out.append(demangled);
+    free(demangled);
+  } else {
+    out.append(mangled);
+  }
+  return out;
+}
+
 }  // namespace debugging_internal
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.h b/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.h
index e1f156989f..146d1150ef 100644
--- a/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.h
+++ b/contrib/restricted/abseil-cpp/absl/debugging/internal/demangle.h
@@ -12,13 +12,23 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// An async-signal-safe and thread-safe demangler for Itanium C++ ABI
-// (aka G++ V3 ABI).
+#ifndef ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
+#define ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
+
+#include <string>
+#include "absl/base/config.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace debugging_internal {
+
+// Demangle `mangled`.  On success, return true and write the
+// demangled symbol name to `out`.  Otherwise, return false.
+// `out` is modified even if demangling is unsuccessful.
 //
-// The demangler is implemented to be used in async signal handlers to
-// symbolize stack traces.  We cannot use libstdc++'s
-// abi::__cxa_demangle() in such signal handlers since it's not async
-// signal safe (it uses malloc() internally).
+// This function provides an alternative to libstdc++'s abi::__cxa_demangle,
+// which is not async signal safe (it uses malloc internally).  It's intended to
+// be used in async signal handlers to symbolize stack traces.
 //
 // Note that this demangler doesn't support full demangling.  More
 // specifically, it doesn't print types of function parameters and
@@ -30,40 +40,32 @@
 //
 // Example:
 //
-// | Mangled Name  | The Demangler | abi::__cxa_demangle()
-// |---------------|---------------|-----------------------
-// | _Z1fv         | f()           | f()
-// | _Z1fi         | f()           | f(int)
-// | _Z3foo3bar    | foo()         | foo(bar)
-// | _Z1fIiEvi     | f<>()         | void f<int>(int)
-// | _ZN1N1fE      | N::f          | N::f
-// | _ZN3Foo3BarEv | Foo::Bar()    | Foo::Bar()
-// | _Zrm1XS_"     | operator%()   | operator%(X, X)
-// | _ZN3FooC1Ev   | Foo::Foo()    | Foo::Foo()
-// | _Z1fSs        | f()           | f(std::basic_string<char,
-// |               |               |   std::char_traits<char>,
-// |               |               |   std::allocator<char> >)
+// | Mangled Name  | Demangle    | DemangleString
+// |---------------|-------------|-----------------------
+// | _Z1fv         | f()         | f()
+// | _Z1fi         | f()         | f(int)
+// | _Z3foo3bar    | foo()       | foo(bar)
+// | _Z1fIiEvi     | f<>()       | void f<int>(int)
+// | _ZN1N1fE      | N::f        | N::f
+// | _ZN3Foo3BarEv | Foo::Bar()  | Foo::Bar()
+// | _Zrm1XS_"     | operator%() | operator%(X, X)
+// | _ZN3FooC1Ev   | Foo::Foo()  | Foo::Foo()
+// | _Z1fSs        | f()         | f(std::basic_string<char,
+// |               |             |   std::char_traits<char>,
+// |               |             |   std::allocator<char> >)
 //
 // See the unit test for more examples.
 //
 // Note: we might want to write demanglers for ABIs other than Itanium
 // C++ ABI in the future.
-//
-
-#ifndef ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
-#define ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
-
-#include "absl/base/config.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace debugging_internal {
-
-// Demangle `mangled`.  On success, return true and write the
-// demangled symbol name to `out`.  Otherwise, return false.
-// `out` is modified even if demangling is unsuccessful.
 bool Demangle(const char* mangled, char* out, size_t out_size);
 
+// A wrapper around `abi::__cxa_demangle()`.  On success, returns the demangled
+// name.  On failure, returns the input mangled name.
+//
+// This function is not async-signal-safe.
+std::string DemangleString(const char* mangled);
+
 }  // namespace debugging_internal
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc b/contrib/restricted/abseil-cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc
index 3f08716202..1caf7bbe35 100644
--- a/contrib/restricted/abseil-cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc
+++ b/contrib/restricted/abseil-cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc
@@ -4,6 +4,7 @@
 // Generate stack tracer for aarch64
 
 #if defined(__linux__)
+#include <signal.h>
 #include <sys/mman.h>
 #include <ucontext.h>
 #include <unistd.h>
@@ -70,7 +71,7 @@ static const unsigned char* GetKernelRtSigreturnAddress() {
 // Compute the size of a stack frame in [low..high).  We assume that
 // low < high.  Return size of kUnknownFrameSize.
 template<typename T>
-static inline size_t ComputeStackFrameSize(const T* low,
+static size_t ComputeStackFrameSize(const T* low,
                                            const T* high) {
   const char* low_char_ptr = reinterpret_cast<const char *>(low);
   const char* high_char_ptr = reinterpret_cast<const char *>(high);
@@ -78,6 +79,20 @@ static inline size_t ComputeStackFrameSize(const T* low,
                     : kUnknownFrameSize;
 }
 
+// Saves stack info that is expensive to calculate to avoid recalculating per frame.
+struct StackInfo {
+  uintptr_t stack_low;
+  uintptr_t stack_high;
+  uintptr_t sig_stack_low;
+  uintptr_t sig_stack_high;
+};
+
+static bool InsideSignalStack(void** ptr, const StackInfo* stack_info) {
+  uintptr_t comparable_ptr = reinterpret_cast<uintptr_t>(ptr);
+  return (comparable_ptr >= stack_info->sig_stack_low &&
+          comparable_ptr < stack_info->sig_stack_high);
+}
+
 // Given a pointer to a stack frame, locate and return the calling
 // stackframe, or return null if no stackframe can be found. Perform sanity
 // checks (the strictness of which is controlled by the boolean parameter
@@ -86,9 +101,8 @@ template<bool STRICT_UNWINDING, bool WITH_CONTEXT>
 ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS  // May read random elements from stack.
 ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY  // May read random elements from stack.
 static void **NextStackFrame(void **old_frame_pointer, const void *uc,
-                             size_t stack_low, size_t stack_high) {
+                             const StackInfo *stack_info) {
   void **new_frame_pointer = reinterpret_cast<void**>(*old_frame_pointer);
-  bool check_frame_size = true;
 
 #if defined(__linux__)
   if (WITH_CONTEXT && uc != nullptr) {
@@ -114,10 +128,6 @@ static void **NextStackFrame(void **old_frame_pointer, const void *uc,
       if (!absl::debugging_internal::AddressIsReadable(
               new_frame_pointer))
         return nullptr;
-
-      // Skip frame size check if we return from a signal. We may be using a
-      // an alternate stack for signals.
-      check_frame_size = false;
     }
   }
 #endif
@@ -126,9 +136,11 @@ static void **NextStackFrame(void **old_frame_pointer, const void *uc,
   if ((reinterpret_cast<uintptr_t>(new_frame_pointer) & 7) != 0)
     return nullptr;
 
-  // Check frame size.  In strict mode, we assume frames to be under
-  // 100,000 bytes.  In non-strict mode, we relax the limit to 1MB.
-  if (check_frame_size) {
+  // Only check the size if both frames are in the same stack.
+  if (InsideSignalStack(new_frame_pointer, stack_info) ==
+      InsideSignalStack(old_frame_pointer, stack_info)) {
+    // Check frame size.  In strict mode, we assume frames to be under
+    // 100,000 bytes.  In non-strict mode, we relax the limit to 1MB.
     const size_t max_size = STRICT_UNWINDING ? 100000 : 1000000;
     const size_t frame_size =
         ComputeStackFrameSize(old_frame_pointer, new_frame_pointer);
@@ -136,15 +148,21 @@ static void **NextStackFrame(void **old_frame_pointer, const void *uc,
        return nullptr;
     // A very large frame may mean corrupt memory or an erroneous frame
     // pointer. But also maybe just a plain-old large frame.  Assume that if the
-    // frame is within the known stack, then it is valid.
+    // frame is within a known stack, then it is valid.
     if (frame_size > max_size) {
-       if (stack_high < kUnknownStackEnd &&
+      size_t stack_low = stack_info->stack_low;
+      size_t stack_high = stack_info->stack_high;
+      if (InsideSignalStack(new_frame_pointer, stack_info)) {
+        stack_low = stack_info->sig_stack_low;
+        stack_high = stack_info->sig_stack_high;
+      }
+      if (stack_high < kUnknownStackEnd &&
           static_cast<size_t>(getpagesize()) < stack_low) {
         const uintptr_t new_fp_u =
             reinterpret_cast<uintptr_t>(new_frame_pointer);
         // Stack bounds are known.
         if (!(stack_low < new_fp_u && new_fp_u <= stack_high)) {
-          // new_frame_pointer is not within the known stack.
+          // new_frame_pointer is not within a known stack.
           return nullptr;
         }
       } else {
@@ -158,6 +176,9 @@ static void **NextStackFrame(void **old_frame_pointer, const void *uc,
 }
 
 template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT>
+// We count on the bottom frame being this one. See the comment
+// at prev_return_address
+ABSL_ATTRIBUTE_NOINLINE
 ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS  // May read random elements from stack.
 ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY   // May read random elements from stack.
 static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
@@ -171,8 +192,11 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
   int n = 0;
 
   // Assume that the first page is not stack.
-  size_t stack_low = static_cast<size_t>(getpagesize());
-  size_t stack_high = kUnknownStackEnd;
+  StackInfo stack_info;
+  stack_info.stack_low = static_cast<uintptr_t>(getpagesize());
+  stack_info.stack_high = kUnknownStackEnd;
+  stack_info.sig_stack_low = stack_info.stack_low;
+  stack_info.sig_stack_high = kUnknownStackEnd;
 
   // The frame pointer points to low address of a frame.  The first 64-bit
   // word of a frame points to the next frame up the call chain, which normally
@@ -207,7 +231,7 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
     // that is as complete as possible (even if it contains a few bogus
     // entries in some rare cases).
     frame_pointer = NextStackFrame<!IS_STACK_FRAMES, IS_WITH_CONTEXT>(
-        frame_pointer, ucp, stack_low, stack_high);
+        frame_pointer, ucp, &stack_info);
   }
 
   if (min_dropped_frames != nullptr) {
@@ -222,7 +246,7 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
         num_dropped_frames++;
       }
       frame_pointer = NextStackFrame<!IS_STACK_FRAMES, IS_WITH_CONTEXT>(
-          frame_pointer, ucp, stack_low, stack_high);
+          frame_pointer, ucp, &stack_info);
     }
     *min_dropped_frames = num_dropped_frames;
   }
diff --git a/contrib/restricted/abseil-cpp/absl/debugging/symbolize_elf.inc b/contrib/restricted/abseil-cpp/absl/debugging/symbolize_elf.inc
index 30638cb2dc..ae75cd4153 100644
--- a/contrib/restricted/abseil-cpp/absl/debugging/symbolize_elf.inc
+++ b/contrib/restricted/abseil-cpp/absl/debugging/symbolize_elf.inc
@@ -289,6 +289,30 @@ ObjFile *AddrMap::Add() {
   return new (&obj_[size_++]) ObjFile;
 }
 
+class CachingFile {
+ public:
+  // Setup reader for fd that uses buf[0, buf_size-1] as a cache.
+  CachingFile(int fd, char *buf, size_t buf_size)
+      : fd_(fd),
+        cache_(buf),
+        cache_size_(buf_size),
+        cache_start_(0),
+        cache_limit_(0) {}
+
+  int fd() const { return fd_; }
+  ssize_t ReadFromOffset(void *buf, size_t count, off_t offset);
+  bool ReadFromOffsetExact(void *buf, size_t count, off_t offset);
+
+ private:
+  // Bytes [cache_start_, cache_limit_-1] from fd_ are stored in
+  // a prefix of cache_[0, cache_size_-1].
+  int fd_;
+  char *cache_;
+  size_t cache_size_;
+  off_t cache_start_;
+  off_t cache_limit_;
+};
+
 // ---------------------------------------------------------------
 
 enum FindSymbolResult { SYMBOL_NOT_FOUND = 1, SYMBOL_TRUNCATED, SYMBOL_FOUND };
@@ -330,6 +354,7 @@ class Symbolizer {
     SYMBOL_BUF_SIZE = 3072,
     TMP_BUF_SIZE = 1024,
     SYMBOL_CACHE_LINES = 128,
+    FILE_CACHE_SIZE = 8192,
   };
 
   AddrMap addr_map_;
@@ -338,6 +363,7 @@ class Symbolizer {
   bool addr_map_read_;
 
   char symbol_buf_[SYMBOL_BUF_SIZE];
+  char file_cache_[FILE_CACHE_SIZE];
 
   // tmp_buf_ will be used to store arrays of ElfW(Shdr) and ElfW(Sym)
   // so we ensure that tmp_buf_ is properly aligned to store either.
@@ -436,34 +462,58 @@ static ssize_t ReadPersistent(int fd, void *buf, size_t count) {
   return static_cast<ssize_t>(num_bytes);
 }
 
-// Read up to "count" bytes from "offset" in the file pointed by file
-// descriptor "fd" into the buffer starting at "buf".  On success,
-// return the number of bytes read.  Otherwise, return -1.
-static ssize_t ReadFromOffset(const int fd, void *buf, const size_t count,
-                              const off_t offset) {
-  off_t off = lseek(fd, offset, SEEK_SET);
-  if (off == (off_t)-1) {
-    ABSL_RAW_LOG(WARNING, "lseek(%d, %jd, SEEK_SET) failed: errno=%d", fd,
-                 static_cast<intmax_t>(offset), errno);
-    return -1;
+// Read up to "count" bytes from "offset" into the buffer starting at "buf",
+// while handling short reads and EINTR.  On success, return the number of bytes
+// read.  Otherwise, return -1.
+ssize_t CachingFile::ReadFromOffset(void *buf, size_t count, off_t offset) {
+  char *dst = static_cast<char *>(buf);
+  size_t read = 0;
+  while (read < count) {
+    // Look in cache first.
+    if (offset >= cache_start_ && offset < cache_limit_) {
+      const char *hit_start = &cache_[offset - cache_start_];
+      const size_t n =
+          std::min(count - read, static_cast<size_t>(cache_limit_ - offset));
+      memcpy(dst, hit_start, n);
+      dst += n;
+      read += static_cast<size_t>(n);
+      offset += static_cast<off_t>(n);
+      continue;
+    }
+
+    cache_start_ = 0;
+    cache_limit_ = 0;
+    ssize_t n = pread(fd_, cache_, cache_size_, offset);
+    if (n < 0) {
+      if (errno == EINTR) {
+        continue;
+      }
+      ABSL_RAW_LOG(WARNING, "read failed: errno=%d", errno);
+      return -1;
+    }
+    if (n == 0) {  // Reached EOF.
+      break;
+    }
+
+    cache_start_ = offset;
+    cache_limit_ = offset + static_cast<off_t>(n);
+    // Next iteration will copy from cache into dst.
   }
-  return ReadPersistent(fd, buf, count);
+  return static_cast<ssize_t>(read);
 }
 
-// Try reading exactly "count" bytes from "offset" bytes in a file
-// pointed by "fd" into the buffer starting at "buf" while handling
-// short reads and EINTR.  On success, return true. Otherwise, return
-// false.
-static bool ReadFromOffsetExact(const int fd, void *buf, const size_t count,
-                                const off_t offset) {
-  ssize_t len = ReadFromOffset(fd, buf, count, offset);
+// Try reading exactly "count" bytes from "offset" bytes into the buffer
+// starting at "buf" while handling short reads and EINTR.  On success, return
+// true. Otherwise, return false.
+bool CachingFile::ReadFromOffsetExact(void *buf, size_t count, off_t offset) {
+  ssize_t len = ReadFromOffset(buf, count, offset);
   return len >= 0 && static_cast<size_t>(len) == count;
 }
 
 // Returns elf_header.e_type if the file pointed by fd is an ELF binary.
-static int FileGetElfType(const int fd) {
+static int FileGetElfType(CachingFile *file) {
   ElfW(Ehdr) elf_header;
-  if (!ReadFromOffsetExact(fd, &elf_header, sizeof(elf_header), 0)) {
+  if (!file->ReadFromOffsetExact(&elf_header, sizeof(elf_header), 0)) {
     return -1;
   }
   if (memcmp(elf_header.e_ident, ELFMAG, SELFMAG) != 0) {
@@ -478,8 +528,8 @@ static int FileGetElfType(const int fd) {
 // To keep stack consumption low, we would like this function to not get
 // inlined.
 static ABSL_ATTRIBUTE_NOINLINE bool GetSectionHeaderByType(
-    const int fd, ElfW(Half) sh_num, const off_t sh_offset, ElfW(Word) type,
-    ElfW(Shdr) * out, char *tmp_buf, size_t tmp_buf_size) {
+    CachingFile *file, ElfW(Half) sh_num, const off_t sh_offset,
+    ElfW(Word) type, ElfW(Shdr) * out, char *tmp_buf, size_t tmp_buf_size) {
   ElfW(Shdr) *buf = reinterpret_cast<ElfW(Shdr) *>(tmp_buf);
   const size_t buf_entries = tmp_buf_size / sizeof(buf[0]);
   const size_t buf_bytes = buf_entries * sizeof(buf[0]);
@@ -490,7 +540,7 @@ static ABSL_ATTRIBUTE_NOINLINE bool GetSectionHeaderByType(
     const size_t num_bytes_to_read =
         (buf_bytes > num_bytes_left) ? num_bytes_left : buf_bytes;
     const off_t offset = sh_offset + static_cast<off_t>(i * sizeof(buf[0]));
-    const ssize_t len = ReadFromOffset(fd, buf, num_bytes_to_read, offset);
+    const ssize_t len = file->ReadFromOffset(buf, num_bytes_to_read, offset);
     if (len < 0) {
       ABSL_RAW_LOG(
           WARNING,
@@ -524,11 +574,17 @@ static ABSL_ATTRIBUTE_NOINLINE bool GetSectionHeaderByType(
 // but there has (as yet) been no need for anything longer either.
 const int kMaxSectionNameLen = 64;
 
+// Small cache to use for miscellaneous file reads.
+const int kSmallFileCacheSize = 100;
+
 bool ForEachSection(int fd,
                     const std::function<bool(absl::string_view name,
                                              const ElfW(Shdr) &)> &callback) {
+  char buf[kSmallFileCacheSize];
+  CachingFile file(fd, buf, sizeof(buf));
+
   ElfW(Ehdr) elf_header;
-  if (!ReadFromOffsetExact(fd, &elf_header, sizeof(elf_header), 0)) {
+  if (!file.ReadFromOffsetExact(&elf_header, sizeof(elf_header), 0)) {
     return false;
   }
 
@@ -540,7 +596,7 @@ bool ForEachSection(int fd,
   ElfW(Shdr) shstrtab;
   off_t shstrtab_offset = static_cast<off_t>(elf_header.e_shoff) +
                           elf_header.e_shentsize * elf_header.e_shstrndx;
-  if (!ReadFromOffsetExact(fd, &shstrtab, sizeof(shstrtab), shstrtab_offset)) {
+  if (!file.ReadFromOffsetExact(&shstrtab, sizeof(shstrtab), shstrtab_offset)) {
     return false;
   }
 
@@ -548,13 +604,13 @@ bool ForEachSection(int fd,
     ElfW(Shdr) out;
     off_t section_header_offset =
         static_cast<off_t>(elf_header.e_shoff) + elf_header.e_shentsize * i;
-    if (!ReadFromOffsetExact(fd, &out, sizeof(out), section_header_offset)) {
+    if (!file.ReadFromOffsetExact(&out, sizeof(out), section_header_offset)) {
       return false;
     }
     off_t name_offset = static_cast<off_t>(shstrtab.sh_offset) + out.sh_name;
     char header_name[kMaxSectionNameLen];
     ssize_t n_read =
-        ReadFromOffset(fd, &header_name, kMaxSectionNameLen, name_offset);
+        file.ReadFromOffset(&header_name, kMaxSectionNameLen, name_offset);
     if (n_read < 0) {
       return false;
     } else if (n_read > kMaxSectionNameLen) {
@@ -584,8 +640,10 @@ bool GetSectionHeaderByName(int fd, const char *name, size_t name_len,
     return false;
   }
 
+  char buf[kSmallFileCacheSize];
+  CachingFile file(fd, buf, sizeof(buf));
   ElfW(Ehdr) elf_header;
-  if (!ReadFromOffsetExact(fd, &elf_header, sizeof(elf_header), 0)) {
+  if (!file.ReadFromOffsetExact(&elf_header, sizeof(elf_header), 0)) {
     return false;
   }
 
@@ -597,18 +655,18 @@ bool GetSectionHeaderByName(int fd, const char *name, size_t name_len,
   ElfW(Shdr) shstrtab;
   off_t shstrtab_offset = static_cast<off_t>(elf_header.e_shoff) +
                           elf_header.e_shentsize * elf_header.e_shstrndx;
-  if (!ReadFromOffsetExact(fd, &shstrtab, sizeof(shstrtab), shstrtab_offset)) {
+  if (!file.ReadFromOffsetExact(&shstrtab, sizeof(shstrtab), shstrtab_offset)) {
     return false;
   }
 
   for (int i = 0; i < elf_header.e_shnum; ++i) {
     off_t section_header_offset =
         static_cast<off_t>(elf_header.e_shoff) + elf_header.e_shentsize * i;
-    if (!ReadFromOffsetExact(fd, out, sizeof(*out), section_header_offset)) {
+    if (!file.ReadFromOffsetExact(out, sizeof(*out), section_header_offset)) {
       return false;
     }
     off_t name_offset = static_cast<off_t>(shstrtab.sh_offset) + out->sh_name;
-    ssize_t n_read = ReadFromOffset(fd, &header_name, name_len, name_offset);
+    ssize_t n_read = file.ReadFromOffset(&header_name, name_len, name_offset);
     if (n_read < 0) {
       return false;
     } else if (static_cast<size_t>(n_read) != name_len) {
@@ -683,7 +741,7 @@ static const char *ComputeOffset(const char *base, ptrdiff_t offset) {
 // To keep stack consumption low, we would like this function to not get
 // inlined.
 static ABSL_ATTRIBUTE_NOINLINE FindSymbolResult FindSymbol(
-    const void *const pc, const int fd, char *out, size_t out_size,
+    const void *const pc, CachingFile *file, char *out, size_t out_size,
     ptrdiff_t relocation, const ElfW(Shdr) * strtab, const ElfW(Shdr) * symtab,
     const ElfW(Shdr) * opd, char *tmp_buf, size_t tmp_buf_size) {
   if (symtab == nullptr) {
@@ -716,7 +774,7 @@ static ABSL_ATTRIBUTE_NOINLINE FindSymbolResult FindSymbol(
     const size_t entries_in_chunk =
         std::min(num_remaining_symbols, buf_entries);
     const size_t bytes_in_chunk = entries_in_chunk * sizeof(buf[0]);
-    const ssize_t len = ReadFromOffset(fd, buf, bytes_in_chunk, offset);
+    const ssize_t len = file->ReadFromOffset(buf, bytes_in_chunk, offset);
     SAFE_ASSERT(len >= 0);
     SAFE_ASSERT(static_cast<size_t>(len) % sizeof(buf[0]) == 0);
     const size_t num_symbols_in_buf = static_cast<size_t>(len) / sizeof(buf[0]);
@@ -772,12 +830,12 @@ static ABSL_ATTRIBUTE_NOINLINE FindSymbolResult FindSymbol(
   if (found_match) {
     const off_t off =
         static_cast<off_t>(strtab->sh_offset) + best_match.st_name;
-    const ssize_t n_read = ReadFromOffset(fd, out, out_size, off);
+    const ssize_t n_read = file->ReadFromOffset(out, out_size, off);
     if (n_read <= 0) {
       // This should never happen.
       ABSL_RAW_LOG(WARNING,
-                   "Unable to read from fd %d at offset %lld: n_read = %zd", fd,
-                   static_cast<long long>(off), n_read);
+                   "Unable to read from fd %d at offset %lld: n_read = %zd",
+                   file->fd(), static_cast<long long>(off), n_read);
       return SYMBOL_NOT_FOUND;
     }
     ABSL_RAW_CHECK(static_cast<size_t>(n_read) <= out_size,
@@ -827,22 +885,24 @@ FindSymbolResult Symbolizer::GetSymbolFromObjectFile(
     }
   }
 
+  CachingFile file(obj.fd, file_cache_, sizeof(file_cache_));
+
   // Consult a regular symbol table, then fall back to the dynamic symbol table.
   for (const auto symbol_table_type : {SHT_SYMTAB, SHT_DYNSYM}) {
-    if (!GetSectionHeaderByType(obj.fd, obj.elf_header.e_shnum,
+    if (!GetSectionHeaderByType(&file, obj.elf_header.e_shnum,
                                 static_cast<off_t>(obj.elf_header.e_shoff),
                                 static_cast<ElfW(Word)>(symbol_table_type),
                                 &symtab, tmp_buf, tmp_buf_size)) {
       continue;
     }
-    if (!ReadFromOffsetExact(
-            obj.fd, &strtab, sizeof(strtab),
+    if (!file.ReadFromOffsetExact(
+            &strtab, sizeof(strtab),
             static_cast<off_t>(obj.elf_header.e_shoff +
                                symtab.sh_link * sizeof(symtab)))) {
       continue;
     }
     const FindSymbolResult rc =
-        FindSymbol(pc, obj.fd, out, out_size, relocation, &strtab, &symtab,
+        FindSymbol(pc, &file, out, out_size, relocation, &strtab, &symtab,
                    opd_ptr, tmp_buf, tmp_buf_size);
     if (rc != SYMBOL_NOT_FOUND) {
       return rc;
@@ -1323,15 +1383,19 @@ static bool MaybeInitializeObjFile(ObjFile *obj) {
       ABSL_RAW_LOG(WARNING, "%s: open failed: errno=%d", obj->filename, errno);
       return false;
     }
-    obj->elf_type = FileGetElfType(obj->fd);
+
+    char buf[kSmallFileCacheSize];
+    CachingFile file(obj->fd, buf, sizeof(buf));
+
+    obj->elf_type = FileGetElfType(&file);
     if (obj->elf_type < 0) {
       ABSL_RAW_LOG(WARNING, "%s: wrong elf type: %d", obj->filename,
                    obj->elf_type);
       return false;
     }
 
-    if (!ReadFromOffsetExact(obj->fd, &obj->elf_header, sizeof(obj->elf_header),
-                             0)) {
+    if (!file.ReadFromOffsetExact(&obj->elf_header, sizeof(obj->elf_header),
+                                  0)) {
       ABSL_RAW_LOG(WARNING, "%s: failed to read elf header", obj->filename);
       return false;
     }
@@ -1341,7 +1405,7 @@ static bool MaybeInitializeObjFile(ObjFile *obj) {
     size_t num_interesting_load_segments = 0;
     for (int j = 0; j < phnum; j++) {
       ElfW(Phdr) phdr;
-      if (!ReadFromOffsetExact(obj->fd, &phdr, sizeof(phdr), phoff)) {
+      if (!file.ReadFromOffsetExact(&phdr, sizeof(phdr), phoff)) {
         ABSL_RAW_LOG(WARNING, "%s: failed to read program header %d",
                      obj->filename, j);
         return false;
diff --git a/contrib/restricted/abseil-cpp/absl/flags/declare.h b/contrib/restricted/abseil-cpp/absl/flags/declare.h
index d1437bb9f6..8d2a856e3b 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/declare.h
+++ b/contrib/restricted/abseil-cpp/absl/flags/declare.h
@@ -40,13 +40,8 @@ class Flag;
 // Flag
 //
 // Forward declaration of the `absl::Flag` type for use in defining the macro.
-#if defined(_MSC_VER) && !defined(__clang__)
-template <typename T>
-class Flag;
-#else
 template <typename T>
 using Flag = flags_internal::Flag<T>;
-#endif
 
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/flags/flag.h b/contrib/restricted/abseil-cpp/absl/flags/flag.h
index b7f94be7c5..06ea6932f9 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/flag.h
+++ b/contrib/restricted/abseil-cpp/absl/flags/flag.h
@@ -71,12 +71,9 @@ ABSL_NAMESPACE_BEGIN
 // For type support of Abseil Flags, see the marshalling.h header file, which
 // discusses supported standard types, optional flags, and additional Abseil
 // type support.
-#if !defined(_MSC_VER) || defined(__clang__)
+
 template <typename T>
 using Flag = flags_internal::Flag<T>;
-#else
-#include "absl/flags/internal/flag_msvc.inc"
-#endif
 
 // GetFlag()
 //
@@ -196,18 +193,12 @@ ABSL_NAMESPACE_END
 // -----------------------------------------------------------------------------
 
 // ABSL_FLAG_IMPL macro definition conditional on ABSL_FLAGS_STRIP_NAMES
-#if !defined(_MSC_VER) || defined(__clang__)
 #define ABSL_FLAG_IMPL_FLAG_PTR(flag) flag
 #define ABSL_FLAG_IMPL_HELP_ARG(name)                      \
   absl::flags_internal::HelpArg<AbslFlagHelpGenFor##name>( \
       FLAGS_help_storage_##name)
 #define ABSL_FLAG_IMPL_DEFAULT_ARG(Type, name) \
   absl::flags_internal::DefaultArg<Type, AbslFlagDefaultGenFor##name>(0)
-#else
-#define ABSL_FLAG_IMPL_FLAG_PTR(flag) flag.GetImpl()
-#define ABSL_FLAG_IMPL_HELP_ARG(name) &AbslFlagHelpGenFor##name::NonConst
-#define ABSL_FLAG_IMPL_DEFAULT_ARG(Type, name) &AbslFlagDefaultGenFor##name::Gen
-#endif
 
 #if ABSL_FLAGS_STRIP_NAMES
 #define ABSL_FLAG_IMPL_FLAGNAME(txt) ""
diff --git a/contrib/restricted/abseil-cpp/absl/flags/internal/flag.h b/contrib/restricted/abseil-cpp/absl/flags/internal/flag.h
index b41f9a69f8..2e6e6b8742 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/internal/flag.h
+++ b/contrib/restricted/abseil-cpp/absl/flags/internal/flag.h
@@ -54,13 +54,8 @@ template <typename T>
 class Flag;
 }  // namespace flags_internal
 
-#if defined(_MSC_VER) && !defined(__clang__)
-template <typename T>
-class Flag;
-#else
 template <typename T>
 using Flag = flags_internal::Flag<T>;
-#endif
 
 template <typename T>
 ABSL_MUST_USE_RESULT T GetFlag(const absl::Flag<T>& flag);
diff --git a/contrib/restricted/abseil-cpp/absl/flags/internal/flag_msvc.inc b/contrib/restricted/abseil-cpp/absl/flags/internal/flag_msvc.inc
deleted file mode 100644
index 614d09fd1a..0000000000
--- a/contrib/restricted/abseil-cpp/absl/flags/internal/flag_msvc.inc
+++ /dev/null
@@ -1,116 +0,0 @@
-//
-//  Copyright 2021 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Do not include this file directly.
-// Include absl/flags/flag.h instead.
-
-// MSVC debug builds do not implement initialization with constexpr constructors
-// correctly. To work around this we add a level of indirection, so that the
-// class `absl::Flag` contains an `internal::Flag*` (instead of being an alias
-// to that class) and dynamically allocates an instance when necessary. We also
-// forward all calls to internal::Flag methods via trampoline methods. In this
-// setup the `absl::Flag` class does not have constructor and virtual methods,
-// all the data members are public and thus MSVC is able to initialize it at
-// link time. To deal with multiple threads accessing the flag for the first
-// time concurrently we use an atomic boolean indicating if flag object is
-// initialized. We also employ the double-checked locking pattern where the
-// second level of protection is a global Mutex, so if two threads attempt to
-// construct the flag concurrently only one wins.
-//
-// This solution is based on a recommendation here:
-// https://developercommunity.visualstudio.com/content/problem/336946/class-with-constexpr-constructor-not-using-static.html?childToView=648454#comment-648454
-
-namespace flags_internal {
-absl::Mutex* GetGlobalConstructionGuard();
-}  // namespace flags_internal
-
-// Public methods of `absl::Flag<T>` are NOT part of the Abseil Flags API.
-// See https://abseil.io/docs/cpp/guides/flags
-template <typename T>
-class Flag {
- public:
-  // No constructor and destructor to ensure this is an aggregate type.
-  // Visual Studio 2015 still requires the constructor for class to be
-  // constexpr initializable.
-#if _MSC_VER <= 1900
-  constexpr Flag(const char* name, const char* filename,
-                 const flags_internal::HelpGenFunc help_gen,
-                 const flags_internal::FlagDfltGenFunc default_value_gen)
-      : name_(name),
-        filename_(filename),
-        help_gen_(help_gen),
-        default_value_gen_(default_value_gen),
-        inited_(false),
-        impl_(nullptr) {}
-#endif
-
-  flags_internal::Flag<T>& GetImpl() const {
-    if (!inited_.load(std::memory_order_acquire)) {
-      absl::MutexLock l(flags_internal::GetGlobalConstructionGuard());
-
-      if (inited_.load(std::memory_order_acquire)) {
-        return *impl_;
-      }
-
-      impl_ = new flags_internal::Flag<T>(
-          name_, filename_,
-          {flags_internal::FlagHelpMsg(help_gen_),
-           flags_internal::FlagHelpKind::kGenFunc},
-          {flags_internal::FlagDefaultSrc(default_value_gen_),
-           flags_internal::FlagDefaultKind::kGenFunc});
-      inited_.store(true, std::memory_order_release);
-    }
-
-    return *impl_;
-  }
-
-  // Public methods of `absl::Flag<T>` are NOT part of the Abseil Flags API.
-  // See https://abseil.io/docs/cpp/guides/flags
-  bool IsRetired() const { return GetImpl().IsRetired(); }
-  absl::string_view Name() const { return GetImpl().Name(); }
-  std::string Help() const { return GetImpl().Help(); }
-  bool IsModified() const { return GetImpl().IsModified(); }
-  bool IsSpecifiedOnCommandLine() const {
-    return GetImpl().IsSpecifiedOnCommandLine();
-  }
-  std::string Filename() const { return GetImpl().Filename(); }
-  std::string DefaultValue() const { return GetImpl().DefaultValue(); }
-  std::string CurrentValue() const { return GetImpl().CurrentValue(); }
-  template <typename U>
-  inline bool IsOfType() const {
-    return GetImpl().template IsOfType<U>();
-  }
-  T Get() const {
-    return flags_internal::FlagImplPeer::InvokeGet<T>(GetImpl());
-  }
-  void Set(const T& v) {
-    flags_internal::FlagImplPeer::InvokeSet(GetImpl(), v);
-  }
-  void InvokeCallback() { GetImpl().InvokeCallback(); }
-
-  const CommandLineFlag& Reflect() const {
-    return flags_internal::FlagImplPeer::InvokeReflect(GetImpl());
-  }
-
-  // The data members are logically private, but they need to be public for
-  // this to be an aggregate type.
-  const char* name_;
-  const char* filename_;
-  const flags_internal::HelpGenFunc help_gen_;
-  const flags_internal::FlagDfltGenFunc default_value_gen_;
-
-  mutable std::atomic<bool> inited_;
-  mutable flags_internal::Flag<T>* impl_;
-};
diff --git a/contrib/restricted/abseil-cpp/absl/flags/internal/usage.cc b/contrib/restricted/abseil-cpp/absl/flags/internal/usage.cc
index 13852e1467..8b169bcdc2 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/internal/usage.cc
+++ b/contrib/restricted/abseil-cpp/absl/flags/internal/usage.cc
@@ -27,7 +27,10 @@
 #include <utility>
 #include <vector>
 
+#include "absl/base/attributes.h"
 #include "absl/base/config.h"
+#include "absl/base/const_init.h"
+#include "absl/base/thread_annotations.h"
 #include "absl/flags/commandlineflag.h"
 #include "absl/flags/flag.h"
 #include "absl/flags/internal/flag.h"
@@ -40,6 +43,8 @@
 #include "absl/strings/str_cat.h"
 #include "absl/strings/str_split.h"
 #include "absl/strings/string_view.h"
+#include "absl/strings/strip.h"
+#include "absl/synchronization/mutex.h"
 
 // Dummy global variables to prevent anyone else defining these.
 bool FLAGS_help = false;
diff --git a/contrib/restricted/abseil-cpp/absl/flags/marshalling.cc b/contrib/restricted/abseil-cpp/absl/flags/marshalling.cc
index dc69754f00..ca4a130572 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/marshalling.cc
+++ b/contrib/restricted/abseil-cpp/absl/flags/marshalling.cc
@@ -247,6 +247,14 @@ bool AbslParseFlag(absl::string_view text, absl::LogSeverity* dst,
     *err = "no value provided";
     return false;
   }
+  if (absl::EqualsIgnoreCase(text, "dfatal")) {
+    *dst = absl::kLogDebugFatal;
+    return true;
+  }
+  if (absl::EqualsIgnoreCase(text, "klogdebugfatal")) {
+    *dst = absl::kLogDebugFatal;
+    return true;
+  }
   if (text.front() == 'k' || text.front() == 'K') text.remove_prefix(1);
   if (absl::EqualsIgnoreCase(text, "info")) {
     *dst = absl::LogSeverity::kInfo;
@@ -269,7 +277,8 @@ bool AbslParseFlag(absl::string_view text, absl::LogSeverity* dst,
     *dst = static_cast<absl::LogSeverity>(numeric_value);
     return true;
   }
-  *err = "only integers and absl::LogSeverity enumerators are accepted";
+  *err =
+      "only integers, absl::LogSeverity enumerators, and DFATAL are accepted";
   return false;
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/flags/parse.cc b/contrib/restricted/abseil-cpp/absl/flags/parse.cc
index 4cdd9d0ad3..526b61d1d1 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/parse.cc
+++ b/contrib/restricted/abseil-cpp/absl/flags/parse.cc
@@ -637,7 +637,7 @@ void ReportUnrecognizedFlags(
 // --------------------------------------------------------------------
 
 bool WasPresentOnCommandLine(absl::string_view flag_name) {
-  absl::MutexLock l(&specified_flags_guard);
+  absl::ReaderMutexLock l(&specified_flags_guard);
   ABSL_INTERNAL_CHECK(specified_flags != nullptr,
                       "ParseCommandLine is not invoked yet");
 
diff --git a/contrib/restricted/abseil-cpp/absl/flags/reflection.cc b/contrib/restricted/abseil-cpp/absl/flags/reflection.cc
index dbce4032ab..841921a926 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/reflection.cc
+++ b/contrib/restricted/abseil-cpp/absl/flags/reflection.cc
@@ -21,6 +21,7 @@
 #include <string>
 
 #include "absl/base/config.h"
+#include "absl/base/no_destructor.h"
 #include "absl/base/thread_annotations.h"
 #include "absl/container/flat_hash_map.h"
 #include "absl/flags/commandlineflag.h"
@@ -169,7 +170,7 @@ void FlagRegistry::RegisterFlag(CommandLineFlag& flag, const char* filename) {
 }
 
 FlagRegistry& FlagRegistry::GlobalRegistry() {
-  static FlagRegistry* global_registry = new FlagRegistry;
+  static absl::NoDestructor<FlagRegistry> global_registry;
   return *global_registry;
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/flags/ya.make b/contrib/restricted/abseil-cpp/absl/flags/ya.make
index f0006d104f..7e6fae43d6 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/flags/ya.make
@@ -30,7 +30,6 @@ NO_UTIL()
 
 SRCS(
     commandlineflag.cc
-    flag.cc
     internal/commandlineflag.cc
     internal/flag.cc
     internal/private_handle_accessor.cc
diff --git a/contrib/restricted/abseil-cpp/absl/functional/function_ref.h b/contrib/restricted/abseil-cpp/absl/functional/function_ref.h
index 2b9139d374..96cece551b 100644
--- a/contrib/restricted/abseil-cpp/absl/functional/function_ref.h
+++ b/contrib/restricted/abseil-cpp/absl/functional/function_ref.h
@@ -137,6 +137,14 @@ class FunctionRef<R(Args...)> {
   absl::functional_internal::Invoker<R, Args...> invoker_;
 };
 
+// Allow const qualified function signatures. Since FunctionRef requires
+// constness anyway we can just make this a no-op.
+template <typename R, typename... Args>
+class FunctionRef<R(Args...) const> : public FunctionRef<R(Args...)> {
+ public:
+  using FunctionRef<R(Args...)>::FunctionRef;
+};
+
 ABSL_NAMESPACE_END
 }  // namespace absl
 
diff --git a/contrib/restricted/abseil-cpp/absl/functional/internal/any_invocable.h b/contrib/restricted/abseil-cpp/absl/functional/internal/any_invocable.h
index f096bb02e1..b04436d1d6 100644
--- a/contrib/restricted/abseil-cpp/absl/functional/internal/any_invocable.h
+++ b/contrib/restricted/abseil-cpp/absl/functional/internal/any_invocable.h
@@ -215,8 +215,8 @@ T& ObjectInLocalStorage(TypeErasedState* const state) {
   // behavior, which works as intended on Abseil's officially supported
   // platforms as of Q2 2022.
 #if !defined(__clang__) && defined(__GNUC__)
-#pragma GCC diagnostic ignored "-Wstrict-aliasing"
 #pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstrict-aliasing"
 #endif
   return *reinterpret_cast<T*>(&state->storage);
 #if !defined(__clang__) && defined(__GNUC__)
@@ -526,10 +526,10 @@ class CoreImpl {
 // Since this is template-heavy code, we prefer to disable these warnings
 // locally instead of adding yet another overload of this function.
 #if !defined(__clang__) && defined(__GNUC__)
+#pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wpragmas"
 #pragma GCC diagnostic ignored "-Waddress"
 #pragma GCC diagnostic ignored "-Wnonnull-compare"
-#pragma GCC diagnostic push
 #endif
     if (static_cast<RemoveCVRef<QualDecayedTRef>>(f) == nullptr) {
 #if !defined(__clang__) && defined(__GNUC__)
diff --git a/contrib/restricted/abseil-cpp/absl/functional/ya.make b/contrib/restricted/abseil-cpp/absl/functional/ya.make
index 3b66e3e400..3f9af85fe6 100644
--- a/contrib/restricted/abseil-cpp/absl/functional/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/functional/ya.make
@@ -6,9 +6,9 @@ LICENSE(Apache-2.0)
 
 LICENSE_TEXTS(.yandex_meta/licenses.list.txt)
 
-VERSION(20230802.1)
+VERSION(20240116.0)
 
-ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20230802.1.tar.gz)
+ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20240116.0.tar.gz)
 
 NO_RUNTIME()
 
diff --git a/contrib/restricted/abseil-cpp/absl/hash/internal/hash.h b/contrib/restricted/abseil-cpp/absl/hash/internal/hash.h
index ef3f366471..f4a94f9129 100644
--- a/contrib/restricted/abseil-cpp/absl/hash/internal/hash.h
+++ b/contrib/restricted/abseil-cpp/absl/hash/internal/hash.h
@@ -19,6 +19,11 @@
 #ifndef ABSL_HASH_INTERNAL_HASH_H_
 #define ABSL_HASH_INTERNAL_HASH_H_
 
+#ifdef __APPLE__
+#include <Availability.h>
+#include <TargetConditionals.h>
+#endif
+
 #include <algorithm>
 #include <array>
 #include <bitset>
@@ -56,6 +61,11 @@
 #include "absl/types/variant.h"
 #include "absl/utility/utility.h"
 
+#if ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L && \
+    !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
+#include <filesystem>  // NOLINT
+#endif
+
 #ifdef ABSL_HAVE_STD_STRING_VIEW
 #include <string_view>
 #endif
@@ -409,9 +419,23 @@ AbslHashValue(H hash_state, LongDouble value) {
   return H::combine(std::move(hash_state), category);
 }
 
+// Without this overload, an array decays to a pointer and we hash that, which
+// is not likely to be what the caller intended.
+template <typename H, typename T, size_t N>
+H AbslHashValue(H hash_state, T (&)[N]) {
+  static_assert(
+      sizeof(T) == -1,
+      "Hashing C arrays is not allowed. For string literals, wrap the literal "
+      "in absl::string_view(). To hash the array contents, use "
+      "absl::MakeSpan() or make the array an std::array. To hash the array "
+      "address, use &array[0].");
+  return hash_state;
+}
+
 // AbslHashValue() for hashing pointers
 template <typename H, typename T>
-H AbslHashValue(H hash_state, T* ptr) {
+std::enable_if_t<std::is_pointer<T>::value, H> AbslHashValue(H hash_state,
+                                                             T ptr) {
   auto v = reinterpret_cast<uintptr_t>(ptr);
   // Due to alignment, pointers tend to have low bits as zero, and the next few
   // bits follow a pattern since they are also multiples of some base value.
@@ -564,6 +588,29 @@ H AbslHashValue(H hash_state, std::basic_string_view<Char> str) {
 
 #endif  // ABSL_HAVE_STD_STRING_VIEW
 
+#if defined(__cpp_lib_filesystem) && __cpp_lib_filesystem >= 201703L && \
+    !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY) && \
+    (!defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) ||        \
+     __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ >= 130000)
+
+#define ABSL_INTERNAL_STD_FILESYSTEM_PATH_HASH_AVAILABLE 1
+
+// Support std::filesystem::path. The SFINAE is required because some string
+// types are implicitly convertible to std::filesystem::path.
+template <typename Path, typename H,
+          typename = absl::enable_if_t<
+              std::is_same_v<Path, std::filesystem::path>>>
+H AbslHashValue(H hash_state, const Path& path) {
+  // This is implemented by deferring to the standard library to compute the
+  // hash.  The standard library requires that for two paths, `p1 == p2`, then
+  // `hash_value(p1) == hash_value(p2)`. `AbslHashValue` has the same
+  // requirement. Since `operator==` does platform specific matching, deferring
+  // to the standard library is the simplest approach.
+  return H::combine(std::move(hash_state), std::filesystem::hash_value(path));
+}
+
+#endif  // ABSL_INTERNAL_STD_FILESYSTEM_PATH_HASH_AVAILABLE
+
 // -----------------------------------------------------------------------------
 // AbslHashValue for Sequence Containers
 // -----------------------------------------------------------------------------
@@ -818,7 +865,7 @@ AbslHashValue(H hash_state, const absl::variant<T...>& v) {
 template <typename H, size_t N>
 H AbslHashValue(H hash_state, const std::bitset<N>& set) {
   typename H::AbslInternalPiecewiseCombiner combiner;
-  for (int i = 0; i < N; i++) {
+  for (size_t i = 0; i < N; i++) {
     unsigned char c = static_cast<unsigned char>(set[i]);
     hash_state = combiner.add_buffer(std::move(hash_state), &c, sizeof(c));
   }
diff --git a/contrib/restricted/abseil-cpp/absl/log/absl_vlog_is_on.h b/contrib/restricted/abseil-cpp/absl/log/absl_vlog_is_on.h
new file mode 100644
index 0000000000..29096b4857
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/log/absl_vlog_is_on.h
@@ -0,0 +1,93 @@
+// Copyright 2022 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: log/absl_vlog_is_on.h
+// -----------------------------------------------------------------------------
+//
+// This header defines the `ABSL_VLOG_IS_ON()` macro that controls the
+// variable-verbosity conditional logging.
+//
+// It's used by `VLOG` in log.h, or it can also be used directly like this:
+//
+//   if (ABSL_VLOG_IS_ON(2)) {
+//     foo_server.RecomputeStatisticsExpensive();
+//     LOG(INFO) << foo_server.LastStatisticsAsString();
+//   }
+//
+// Each source file has an effective verbosity level that's a non-negative
+// integer computed from the `--vmodule` and `--v` flags.
+// `ABSL_VLOG_IS_ON(n)` is true, and `VLOG(n)` logs, if that effective verbosity
+// level is greater than or equal to `n`.
+//
+// `--vmodule` takes a comma-delimited list of key=value pairs.  Each key is a
+// pattern matched against filenames, and the values give the effective severity
+// level applied to matching files.  '?' and '*' characters in patterns are
+// interpreted as single-character and zero-or-more-character wildcards.
+// Patterns including a slash character are matched against full pathnames,
+// while those without are matched against basenames only.  One suffix (i.e. the
+// last . and everything after it) is stripped from each filename prior to
+// matching, as is the special suffix "-inl".
+//
+// Files are matched against globs in `--vmodule` in order, and the first match
+// determines the verbosity level.
+//
+// Files which do not match any pattern in `--vmodule` use the value of `--v` as
+// their effective verbosity level.  The default is 0.
+//
+// SetVLOGLevel helper function is provided to do limited dynamic control over
+// V-logging by appending to `--vmodule`. Because these go at the beginning of
+// the list, they take priority over any globs previously added.
+//
+// Resetting --vmodule will override all previous modifications to `--vmodule`,
+// including via SetVLOGLevel.
+
+#ifndef ABSL_LOG_ABSL_VLOG_IS_ON_H_
+#define ABSL_LOG_ABSL_VLOG_IS_ON_H_
+
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/log/internal/vlog_config.h"  // IWYU pragma: export
+#include "absl/strings/string_view.h"
+
+// IWYU pragma: private, include "absl/log/log.h"
+
+// This is expanded at the callsite to allow the compiler to optimize
+// always-false cases out of the build.
+// An ABSL_MAX_VLOG_VERBOSITY of 2 means that VLOG(3) and above should never
+// log.
+#ifdef ABSL_MAX_VLOG_VERBOSITY
+#define ABSL_LOG_INTERNAL_MAX_LOG_VERBOSITY_CHECK(x) \
+  ((x) <= ABSL_MAX_VLOG_VERBOSITY)&&
+#else
+#define ABSL_LOG_INTERNAL_MAX_LOG_VERBOSITY_CHECK(x)
+#endif
+
+// Each ABSL_VLOG_IS_ON call site gets its own VLogSite that registers with the
+// global linked list of sites to asynchronously update its verbosity level on
+// changes to --v or --vmodule. The verbosity can also be set by manually
+// calling SetVLOGLevel.
+//
+// ABSL_VLOG_IS_ON is not async signal safe, but it is guaranteed not to
+// allocate new memory.
+#define ABSL_VLOG_IS_ON(verbose_level)                                     \
+  (ABSL_LOG_INTERNAL_MAX_LOG_VERBOSITY_CHECK(verbose_level)[]()            \
+       ->::absl::log_internal::VLogSite *                                  \
+   {                                                                       \
+     ABSL_CONST_INIT static ::absl::log_internal::VLogSite site(__FILE__); \
+     return &site;                                                         \
+   }()                                                                     \
+       ->IsEnabled(verbose_level))
+
+#endif  // ABSL_LOG_ABSL_VLOG_IS_ON_H_
diff --git a/contrib/restricted/abseil-cpp/absl/log/flags.cc b/contrib/restricted/abseil-cpp/absl/log/flags.cc
index 215b7bd580..287b3e96c7 100644
--- a/contrib/restricted/abseil-cpp/absl/log/flags.cc
+++ b/contrib/restricted/abseil-cpp/absl/log/flags.cc
@@ -28,6 +28,7 @@
 #include "absl/flags/marshalling.h"
 #include "absl/log/globals.h"
 #include "absl/log/internal/config.h"
+#include "absl/log/internal/vlog_config.h"
 #include "absl/strings/numbers.h"
 #include "absl/strings/string_view.h"
 
@@ -118,3 +119,25 @@ ABSL_FLAG(bool, log_prefix, true,
     .OnUpdate([] {
       absl::log_internal::RawEnableLogPrefix(absl::GetFlag(FLAGS_log_prefix));
     });
+
+ABSL_FLAG(int, v, 0,
+          "Show all VLOG(m) messages for m <= this. Overridable by --vmodule.")
+    .OnUpdate([] {
+      absl::log_internal::UpdateGlobalVLogLevel(absl::GetFlag(FLAGS_v));
+    });
+
+ABSL_FLAG(
+    std::string, vmodule, "",
+    "per-module log verbosity level."
+    " Argument is a comma-separated list of <module name>=<log level>."
+    " <module name> is a glob pattern, matched against the filename base"
+    " (that is, name ignoring .cc/.h./-inl.h)."
+    " A pattern without slashes matches just the file name portion, otherwise"
+    " the whole file path below the workspace root"
+    " (still without .cc/.h./-inl.h) is matched."
+    " ? and * in the glob pattern match any single or sequence of characters"
+    " respectively including slashes."
+    " <log level> overrides any value given by --v.")
+    .OnUpdate([] {
+      absl::log_internal::UpdateVModule(absl::GetFlag(FLAGS_vmodule));
+    });
diff --git a/contrib/restricted/abseil-cpp/absl/log/globals.h b/contrib/restricted/abseil-cpp/absl/log/globals.h
index bc3864c110..b36e47e6d1 100644
--- a/contrib/restricted/abseil-cpp/absl/log/globals.h
+++ b/contrib/restricted/abseil-cpp/absl/log/globals.h
@@ -24,6 +24,7 @@
 #include "absl/base/attributes.h"
 #include "absl/base/config.h"
 #include "absl/base/log_severity.h"
+#include "absl/log/internal/vlog_config.h"
 #include "absl/strings/string_view.h"
 
 namespace absl {
@@ -153,6 +154,28 @@ ABSL_MUST_USE_RESULT bool ShouldPrependLogPrefix();
 void EnableLogPrefix(bool on_off);
 
 //------------------------------------------------------------------------------
+// Set Global VLOG Level
+//------------------------------------------------------------------------------
+//
+// Sets the global `(ABSL_)VLOG(_IS_ON)` level to `log_level`.  This level is
+// applied to any sites whose filename doesn't match any `module_pattern`.
+// Returns the prior value.
+inline int SetGlobalVLogLevel(int log_level) {
+  return absl::log_internal::UpdateGlobalVLogLevel(log_level);
+}
+
+//------------------------------------------------------------------------------
+// Set VLOG Level
+//------------------------------------------------------------------------------
+//
+// Sets `(ABSL_)VLOG(_IS_ON)` level for `module_pattern` to `log_level`.  This
+// allows programmatic control of what is normally set by the --vmodule flag.
+// Returns the level that previously applied to `module_pattern`.
+inline int SetVLogLevel(absl::string_view module_pattern, int log_level) {
+  return absl::log_internal::PrependVModule(module_pattern, log_level);
+}
+
+//------------------------------------------------------------------------------
 // Configure Android Native Log Tag
 //------------------------------------------------------------------------------
 //
diff --git a/contrib/restricted/abseil-cpp/absl/log/initialize.cc b/contrib/restricted/abseil-cpp/absl/log/initialize.cc
index a3f6d6c142..ef5d31469a 100644
--- a/contrib/restricted/abseil-cpp/absl/log/initialize.cc
+++ b/contrib/restricted/abseil-cpp/absl/log/initialize.cc
@@ -21,14 +21,18 @@
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
-void InitializeLog() {
+namespace {
+void InitializeLogImpl(absl::TimeZone time_zone) {
   // This comes first since it is used by RAW_LOG.
-  absl::log_internal::SetTimeZone(absl::LocalTimeZone());
+  absl::log_internal::SetTimeZone(time_zone);
 
   // Note that initialization is complete, so logs can now be sent to their
   // proper destinations rather than stderr.
   log_internal::SetInitialized();
 }
+}  // namespace
+
+void InitializeLog() { InitializeLogImpl(absl::LocalTimeZone()); }
 
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/check_op.h b/contrib/restricted/abseil-cpp/absl/log/internal/check_op.h
index 20b01b5e84..11f0f4078b 100644
--- a/contrib/restricted/abseil-cpp/absl/log/internal/check_op.h
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/check_op.h
@@ -65,6 +65,7 @@
               ::absl::log_internal::GetReferenceableValue(val2),               \
               ABSL_LOG_INTERNAL_STRIP_STRING_LITERAL(val1_text                 \
                                                      " " #op " " val2_text)))  \
+    ABSL_LOG_INTERNAL_CONDITION_FATAL(STATELESS, true)                         \
   ABSL_LOG_INTERNAL_CHECK(*absl_log_internal_check_op_result).InternalStream()
 #define ABSL_LOG_INTERNAL_QCHECK_OP(name, op, val1, val1_text, val2, \
                                     val2_text)                       \
@@ -74,6 +75,7 @@
                  ::absl::log_internal::GetReferenceableValue(val2),  \
                  ABSL_LOG_INTERNAL_STRIP_STRING_LITERAL(             \
                      val1_text " " #op " " val2_text)))              \
+    ABSL_LOG_INTERNAL_CONDITION_QFATAL(STATELESS, true)              \
   ABSL_LOG_INTERNAL_QCHECK(*absl_log_internal_qcheck_op_result).InternalStream()
 #define ABSL_LOG_INTERNAL_CHECK_STROP(func, op, expected, s1, s1_text, s2,     \
                                       s2_text)                                 \
@@ -82,6 +84,7 @@
                  (s1), (s2),                                                   \
                  ABSL_LOG_INTERNAL_STRIP_STRING_LITERAL(s1_text " " #op        \
                                                                 " " s2_text))) \
+    ABSL_LOG_INTERNAL_CONDITION_FATAL(STATELESS, true)                         \
   ABSL_LOG_INTERNAL_CHECK(*absl_log_internal_check_strop_result)               \
       .InternalStream()
 #define ABSL_LOG_INTERNAL_QCHECK_STROP(func, op, expected, s1, s1_text, s2,    \
@@ -91,6 +94,7 @@
                  (s1), (s2),                                                   \
                  ABSL_LOG_INTERNAL_STRIP_STRING_LITERAL(s1_text " " #op        \
                                                                 " " s2_text))) \
+    ABSL_LOG_INTERNAL_CONDITION_QFATAL(STATELESS, true)                        \
   ABSL_LOG_INTERNAL_QCHECK(*absl_log_internal_qcheck_strop_result)             \
       .InternalStream()
 // This one is tricky:
@@ -113,6 +117,10 @@
 // * As usual, no braces so we can stream into the expansion with `operator<<`.
 // * Also as usual, it must expand to a single (partial) statement with no
 //   ambiguous-else problems.
+// * When stripped by `ABSL_MIN_LOG_LEVEL`, we must discard the `<expr> is OK`
+//   string literal and abort without doing any streaming.  We don't need to
+//   strip the call to stringify the non-ok `Status` as long as we don't log it;
+//   dropping the `Status`'s message text is out of scope.
 #define ABSL_LOG_INTERNAL_CHECK_OK(val, val_text)                        \
   for (::std::pair<const ::absl::Status*, ::std::string*>                \
            absl_log_internal_check_ok_goo;                               \
@@ -126,22 +134,24 @@
                      ABSL_LOG_INTERNAL_STRIP_STRING_LITERAL(val_text     \
                                                             " is OK")),  \
        !ABSL_PREDICT_TRUE(absl_log_internal_check_ok_goo.first->ok());)  \
+    ABSL_LOG_INTERNAL_CONDITION_FATAL(STATELESS, true)                   \
   ABSL_LOG_INTERNAL_CHECK(*absl_log_internal_check_ok_goo.second)        \
       .InternalStream()
-#define ABSL_LOG_INTERNAL_QCHECK_OK(val, val_text)                       \
-  for (::std::pair<const ::absl::Status*, ::std::string*>                \
-           absl_log_internal_check_ok_goo;                               \
-       absl_log_internal_check_ok_goo.first =                            \
-           ::absl::log_internal::AsStatus(val),                          \
-       absl_log_internal_check_ok_goo.second =                           \
-           ABSL_PREDICT_TRUE(absl_log_internal_check_ok_goo.first->ok()) \
-               ? nullptr                                                 \
-               : ::absl::status_internal::MakeCheckFailString(           \
-                     absl_log_internal_check_ok_goo.first,               \
-                     ABSL_LOG_INTERNAL_STRIP_STRING_LITERAL(val_text     \
-                                                            " is OK")),  \
-       !ABSL_PREDICT_TRUE(absl_log_internal_check_ok_goo.first->ok());)  \
-  ABSL_LOG_INTERNAL_QCHECK(*absl_log_internal_check_ok_goo.second)       \
+#define ABSL_LOG_INTERNAL_QCHECK_OK(val, val_text)                        \
+  for (::std::pair<const ::absl::Status*, ::std::string*>                 \
+           absl_log_internal_qcheck_ok_goo;                               \
+       absl_log_internal_qcheck_ok_goo.first =                            \
+           ::absl::log_internal::AsStatus(val),                           \
+       absl_log_internal_qcheck_ok_goo.second =                           \
+           ABSL_PREDICT_TRUE(absl_log_internal_qcheck_ok_goo.first->ok()) \
+               ? nullptr                                                  \
+               : ::absl::status_internal::MakeCheckFailString(            \
+                     absl_log_internal_qcheck_ok_goo.first,               \
+                     ABSL_LOG_INTERNAL_STRIP_STRING_LITERAL(val_text      \
+                                                            " is OK")),   \
+       !ABSL_PREDICT_TRUE(absl_log_internal_qcheck_ok_goo.first->ok());)  \
+    ABSL_LOG_INTERNAL_CONDITION_QFATAL(STATELESS, true)                   \
+  ABSL_LOG_INTERNAL_QCHECK(*absl_log_internal_qcheck_ok_goo.second)       \
       .InternalStream()
 
 namespace absl {
@@ -152,8 +162,8 @@ template <typename T>
 class StatusOr;
 
 namespace status_internal {
-std::string* MakeCheckFailString(const absl::Status* status,
-                                 const char* prefix);
+ABSL_ATTRIBUTE_PURE_FUNCTION std::string* MakeCheckFailString(
+    const absl::Status* status, const char* prefix);
 }  // namespace status_internal
 
 namespace log_internal {
@@ -314,6 +324,20 @@ ABSL_LOG_INTERNAL_DEFINE_MAKE_CHECK_OP_STRING_EXTERN(const unsigned char*);
 ABSL_LOG_INTERNAL_DEFINE_MAKE_CHECK_OP_STRING_EXTERN(const void*);
 #undef ABSL_LOG_INTERNAL_DEFINE_MAKE_CHECK_OP_STRING_EXTERN
 
+// `ABSL_LOG_INTERNAL_CHECK_OP_IMPL_RESULT` skips formatting the Check_OP result
+// string iff `ABSL_MIN_LOG_LEVEL` exceeds `kFatal`, instead returning an empty
+// string.
+#ifdef ABSL_MIN_LOG_LEVEL
+#define ABSL_LOG_INTERNAL_CHECK_OP_IMPL_RESULT(U1, U2, v1, v2, exprtext) \
+  ((::absl::LogSeverity::kFatal >=                                       \
+    static_cast<::absl::LogSeverity>(ABSL_MIN_LOG_LEVEL))                \
+       ? MakeCheckOpString<U1, U2>(v1, v2, exprtext)                     \
+       : new std::string())
+#else
+#define ABSL_LOG_INTERNAL_CHECK_OP_IMPL_RESULT(U1, U2, v1, v2, exprtext) \
+  MakeCheckOpString<U1, U2>(v1, v2, exprtext)
+#endif
+
 // Helper functions for `ABSL_LOG_INTERNAL_CHECK_OP` macro family.  The
 // `(int, int)` override works around the issue that the compiler will not
 // instantiate the template version of the function on values of unnamed enum
@@ -326,7 +350,8 @@ ABSL_LOG_INTERNAL_DEFINE_MAKE_CHECK_OP_STRING_EXTERN(const void*);
     using U2 = CheckOpStreamType<T2>;                                    \
     return ABSL_PREDICT_TRUE(v1 op v2)                                   \
                ? nullptr                                                 \
-               : MakeCheckOpString<U1, U2>(v1, v2, exprtext);            \
+               : ABSL_LOG_INTERNAL_CHECK_OP_IMPL_RESULT(U1, U2, v1, v2,  \
+                                                        exprtext);       \
   }                                                                      \
   inline constexpr ::std::string* name##Impl(int v1, int v2,             \
                                              const char* exprtext) {     \
@@ -339,6 +364,7 @@ ABSL_LOG_INTERNAL_CHECK_OP_IMPL(Check_LE, <=)
 ABSL_LOG_INTERNAL_CHECK_OP_IMPL(Check_LT, <)
 ABSL_LOG_INTERNAL_CHECK_OP_IMPL(Check_GE, >=)
 ABSL_LOG_INTERNAL_CHECK_OP_IMPL(Check_GT, >)
+#undef ABSL_LOG_INTERNAL_CHECK_OP_IMPL_RESULT
 #undef ABSL_LOG_INTERNAL_CHECK_OP_IMPL
 
 std::string* CheckstrcmptrueImpl(const char* s1, const char* s2,
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/conditions.h b/contrib/restricted/abseil-cpp/absl/log/internal/conditions.h
index f576d6500b..645f3c23ea 100644
--- a/contrib/restricted/abseil-cpp/absl/log/internal/conditions.h
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/conditions.h
@@ -57,7 +57,7 @@
 // (dangling else, missing switch case) and preserving noreturn semantics (e.g.
 // on `LOG(FATAL)`) without requiring braces.
 //
-// The `switch` ensures that this expansion is the begnning of a statement (as
+// The `switch` ensures that this expansion is the beginning of a statement (as
 // opposed to an expression) and prevents shenanigans like
 // `AFunction(LOG(INFO))` and `decltype(LOG(INFO))`.  The apparently-redundant
 // `default` case makes the condition more amenable to Clang dataflow analysis.
@@ -68,7 +68,7 @@
     !(condition) ? (void)0 : ::absl::log_internal::Voidify()&&
 
 // `ABSL_LOG_INTERNAL_STATEFUL_CONDITION` applies a condition like
-// `ABSL_LOG_INTERNAL_CONDITION` but adds to that a series of variable
+// `ABSL_LOG_INTERNAL_STATELESS_CONDITION` but adds to that a series of variable
 // declarations, including a local static object which stores the state needed
 // to implement the stateful macros like `LOG_EVERY_N`.
 //
@@ -137,21 +137,30 @@
                   ? true                                                   \
                   : (::absl::log_internal::ExitQuietly(), false))          \
            : false))
-
-#define ABSL_LOG_INTERNAL_CONDITION_LEVEL(severity)                    \
-  for (int log_internal_severity_loop = 1; log_internal_severity_loop; \
-       log_internal_severity_loop = 0)                                 \
-    for (const absl::LogSeverity log_internal_severity =               \
-             ::absl::NormalizeLogSeverity(severity);                   \
-         log_internal_severity_loop; log_internal_severity_loop = 0)   \
+#define ABSL_LOG_INTERNAL_CONDITION_DFATAL(type, condition)             \
+  ABSL_LOG_INTERNAL_##type##_CONDITION(                                 \
+      (ABSL_ASSUME(absl::kLogDebugFatal == absl::LogSeverity::kError || \
+                   absl::kLogDebugFatal == absl::LogSeverity::kFatal),  \
+       (condition) &&                                                   \
+           (::absl::kLogDebugFatal >=                                   \
+                static_cast<::absl::LogSeverity>(ABSL_MIN_LOG_LEVEL) || \
+            (::absl::kLogDebugFatal == ::absl::LogSeverity::kFatal &&   \
+             (::absl::log_internal::AbortQuietly(), false)))))
+
+#define ABSL_LOG_INTERNAL_CONDITION_LEVEL(severity)                            \
+  for (int absl_log_internal_severity_loop = 1;                                \
+       absl_log_internal_severity_loop; absl_log_internal_severity_loop = 0)   \
+    for (const absl::LogSeverity absl_log_internal_severity =                  \
+             ::absl::NormalizeLogSeverity(severity);                           \
+         absl_log_internal_severity_loop; absl_log_internal_severity_loop = 0) \
   ABSL_LOG_INTERNAL_CONDITION_LEVEL_IMPL
-#define ABSL_LOG_INTERNAL_CONDITION_LEVEL_IMPL(type, condition)    \
-  ABSL_LOG_INTERNAL_##type##_CONDITION(                            \
-      (condition) &&                                               \
-      (log_internal_severity >=                                    \
-           static_cast<::absl::LogSeverity>(ABSL_MIN_LOG_LEVEL) || \
-       (log_internal_severity == ::absl::LogSeverity::kFatal &&    \
-        (::absl::log_internal::AbortQuietly(), false))))
+#define ABSL_LOG_INTERNAL_CONDITION_LEVEL_IMPL(type, condition)          \
+  ABSL_LOG_INTERNAL_##type##_CONDITION((                                  \
+      (condition) &&                                                     \
+          (absl_log_internal_severity >=                                 \
+               static_cast<::absl::LogSeverity>(ABSL_MIN_LOG_LEVEL) ||   \
+           (absl_log_internal_severity == ::absl::LogSeverity::kFatal && \
+            (::absl::log_internal::AbortQuietly(), false)))))
 #else  // ndef ABSL_MIN_LOG_LEVEL
 #define ABSL_LOG_INTERNAL_CONDITION_INFO(type, condition) \
   ABSL_LOG_INTERNAL_##type##_CONDITION(condition)
@@ -163,12 +172,14 @@
   ABSL_LOG_INTERNAL_##type##_CONDITION(condition)
 #define ABSL_LOG_INTERNAL_CONDITION_QFATAL(type, condition) \
   ABSL_LOG_INTERNAL_##type##_CONDITION(condition)
-#define ABSL_LOG_INTERNAL_CONDITION_LEVEL(severity)                    \
-  for (int log_internal_severity_loop = 1; log_internal_severity_loop; \
-       log_internal_severity_loop = 0)                                 \
-    for (const absl::LogSeverity log_internal_severity =               \
-             ::absl::NormalizeLogSeverity(severity);                   \
-         log_internal_severity_loop; log_internal_severity_loop = 0)   \
+#define ABSL_LOG_INTERNAL_CONDITION_DFATAL(type, condition) \
+  ABSL_LOG_INTERNAL_##type##_CONDITION(condition)
+#define ABSL_LOG_INTERNAL_CONDITION_LEVEL(severity)                            \
+  for (int absl_log_internal_severity_loop = 1;                                \
+       absl_log_internal_severity_loop; absl_log_internal_severity_loop = 0)   \
+    for (const absl::LogSeverity absl_log_internal_severity =                  \
+             ::absl::NormalizeLogSeverity(severity);                           \
+         absl_log_internal_severity_loop; absl_log_internal_severity_loop = 0) \
   ABSL_LOG_INTERNAL_CONDITION_LEVEL_IMPL
 #define ABSL_LOG_INTERNAL_CONDITION_LEVEL_IMPL(type, condition) \
   ABSL_LOG_INTERNAL_##type##_CONDITION(condition)
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/flags.h b/contrib/restricted/abseil-cpp/absl/log/internal/flags.h
index 0c5e81edee..c4539785ad 100644
--- a/contrib/restricted/abseil-cpp/absl/log/internal/flags.h
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/flags.h
@@ -33,7 +33,7 @@
 // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
 // Log messages at this severity or above are sent to stderr in *addition* to
-// logfiles.  Defaults to `ERROR`.  See log_severity.h for numeric values of
+// `LogSink`s.  Defaults to `ERROR`.  See log_severity.h for numeric values of
 // severity levels.
 ABSL_DECLARE_FLAG(int, stderrthreshold);
 
@@ -50,4 +50,10 @@ ABSL_DECLARE_FLAG(std::string, log_backtrace_at);
 // each message logged. Defaults to true.
 ABSL_DECLARE_FLAG(bool, log_prefix);
 
+// Global log verbosity level. Default is 0.
+ABSL_DECLARE_FLAG(int, v);
+
+// Per-module log verbosity level. By default is empty and is unused.
+ABSL_DECLARE_FLAG(std::string, vmodule);
+
 #endif  // ABSL_LOG_INTERNAL_FLAGS_H_
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/fnmatch.cc b/contrib/restricted/abseil-cpp/absl/log/internal/fnmatch.cc
new file mode 100644
index 0000000000..26e1e57fe4
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/fnmatch.cc
@@ -0,0 +1,73 @@
+// Copyright 2023 The Abseil Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/log/internal/fnmatch.h"
+
+#include <cstddef>
+
+#include "absl/base/config.h"
+#include "absl/strings/string_view.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace log_internal {
+bool FNMatch(absl::string_view pattern, absl::string_view str) {
+  bool in_wildcard_match = false;
+  while (true) {
+    if (pattern.empty()) {
+      // `pattern` is exhausted; succeed if all of `str` was consumed matching
+      // it.
+      return in_wildcard_match || str.empty();
+    }
+    if (str.empty()) {
+      // `str` is exhausted; succeed if `pattern` is empty or all '*'s.
+      return pattern.find_first_not_of('*') == pattern.npos;
+    }
+    switch (pattern.front()) {
+      case '*':
+        pattern.remove_prefix(1);
+        in_wildcard_match = true;
+        break;
+      case '?':
+        pattern.remove_prefix(1);
+        str.remove_prefix(1);
+        break;
+      default:
+        if (in_wildcard_match) {
+          absl::string_view fixed_portion = pattern;
+          const size_t end = fixed_portion.find_first_of("*?");
+          if (end != fixed_portion.npos) {
+            fixed_portion = fixed_portion.substr(0, end);
+          }
+          const size_t match = str.find(fixed_portion);
+          if (match == str.npos) {
+            return false;
+          }
+          pattern.remove_prefix(fixed_portion.size());
+          str.remove_prefix(match + fixed_portion.size());
+          in_wildcard_match = false;
+        } else {
+          if (pattern.front() != str.front()) {
+            return false;
+          }
+          pattern.remove_prefix(1);
+          str.remove_prefix(1);
+        }
+        break;
+    }
+  }
+}
+}  // namespace log_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/flags/flag.cc b/contrib/restricted/abseil-cpp/absl/log/internal/fnmatch.h
index 531df1287a..4ea147cc6f 100644
--- a/contrib/restricted/abseil-cpp/absl/flags/flag.cc
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/fnmatch.h
@@ -1,11 +1,10 @@
-//
-//  Copyright 2019 The Abseil Authors.
+// Copyright 2023 The Abseil Authors
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
-//      https://www.apache.org/licenses/LICENSE-2.0
+//     https://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ -13,26 +12,24 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "absl/flags/flag.h"
+#ifndef ABSL_LOG_INTERNAL_FNMATCH_H_
+#define ABSL_LOG_INTERNAL_FNMATCH_H_
 
 #include "absl/base/config.h"
+#include "absl/strings/string_view.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
-
-// This global mutex protects on-demand construction of flag objects in MSVC
-// builds.
-#if defined(_MSC_VER) && !defined(__clang__)
-
-namespace flags_internal {
-
-ABSL_CONST_INIT static absl::Mutex construction_guard(absl::kConstInit);
-
-absl::Mutex* GetGlobalConstructionGuard() { return &construction_guard; }
-
-}  // namespace flags_internal
-
-#endif
-
+namespace log_internal {
+// Like POSIX `fnmatch`, but:
+// * accepts `string_view`
+// * does not allocate any dynamic memory
+// * only supports * and ? wildcards and not bracket expressions [...]
+// * wildcards may match /
+// * no backslash-escaping
+bool FNMatch(absl::string_view pattern, absl::string_view str);
+}  // namespace log_internal
 ABSL_NAMESPACE_END
 }  // namespace absl
+
+#endif  // ABSL_LOG_INTERNAL_FNMATCH_H_
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/log_impl.h b/contrib/restricted/abseil-cpp/absl/log/internal/log_impl.h
index 9326780dc6..99de6dbb24 100644
--- a/contrib/restricted/abseil-cpp/absl/log/internal/log_impl.h
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/log_impl.h
@@ -15,6 +15,7 @@
 #ifndef ABSL_LOG_INTERNAL_LOG_IMPL_H_
 #define ABSL_LOG_INTERNAL_LOG_IMPL_H_
 
+#include "absl/log/absl_vlog_is_on.h"
 #include "absl/log/internal/conditions.h"
 #include "absl/log/internal/log_message.h"
 #include "absl/log/internal/strip.h"
@@ -41,6 +42,35 @@
       ABSL_LOGGING_INTERNAL_LOG##severity.InternalStream()
 #endif
 
+// The `switch` ensures that this expansion is the begnning of a statement (as
+// opposed to an expression). The use of both `case 0` and `default` is to
+// suppress a compiler warning.
+#define ABSL_LOG_INTERNAL_VLOG_IMPL(verbose_level)                         \
+  switch (const int absl_logging_internal_verbose_level = (verbose_level)) \
+  case 0:                                                                  \
+  default:                                                                 \
+    ABSL_LOG_INTERNAL_LOG_IF_IMPL(                                         \
+        _INFO, ABSL_VLOG_IS_ON(absl_logging_internal_verbose_level))       \
+        .WithVerbosity(absl_logging_internal_verbose_level)
+
+#ifndef NDEBUG
+#define ABSL_LOG_INTERNAL_DVLOG_IMPL(verbose_level)                        \
+  switch (const int absl_logging_internal_verbose_level = (verbose_level)) \
+  case 0:                                                                  \
+  default:                                                                 \
+    ABSL_LOG_INTERNAL_LOG_IF_IMPL(                                         \
+        _INFO, ABSL_VLOG_IS_ON(absl_logging_internal_verbose_level))       \
+        .WithVerbosity(absl_logging_internal_verbose_level)
+#else
+#define ABSL_LOG_INTERNAL_DVLOG_IMPL(verbose_level)                           \
+  switch (const int absl_logging_internal_verbose_level = (verbose_level))    \
+  case 0:                                                                     \
+  default:                                                                    \
+    ABSL_LOG_INTERNAL_LOG_IF_IMPL(                                            \
+        _INFO, false && ABSL_VLOG_IS_ON(absl_logging_internal_verbose_level)) \
+        .WithVerbosity(absl_logging_internal_verbose_level)
+#endif
+
 #define ABSL_LOG_INTERNAL_LOG_IF_IMPL(severity, condition)    \
   ABSL_LOG_INTERNAL_CONDITION##severity(STATELESS, condition) \
       ABSL_LOGGING_INTERNAL_LOG##severity.InternalStream()
@@ -134,6 +164,42 @@
   (EveryNSec, n_seconds) ABSL_LOGGING_INTERNAL_LOG##severity.InternalStream()
 #endif  // def NDEBUG
 
+#define ABSL_LOG_INTERNAL_VLOG_EVERY_N_IMPL(verbose_level, n)                \
+  switch (const int absl_logging_internal_verbose_level = (verbose_level))   \
+  case 0:                                                                    \
+  default:                                                                   \
+    ABSL_LOG_INTERNAL_CONDITION_INFO(                                        \
+        STATEFUL, ABSL_VLOG_IS_ON(absl_logging_internal_verbose_level))      \
+  (EveryN, n) ABSL_LOGGING_INTERNAL_LOG_INFO.InternalStream().WithVerbosity( \
+      absl_logging_internal_verbose_level)
+
+#define ABSL_LOG_INTERNAL_VLOG_FIRST_N_IMPL(verbose_level, n)                \
+  switch (const int absl_logging_internal_verbose_level = (verbose_level))   \
+  case 0:                                                                    \
+  default:                                                                   \
+    ABSL_LOG_INTERNAL_CONDITION_INFO(                                        \
+        STATEFUL, ABSL_VLOG_IS_ON(absl_logging_internal_verbose_level))      \
+  (FirstN, n) ABSL_LOGGING_INTERNAL_LOG_INFO.InternalStream().WithVerbosity( \
+      absl_logging_internal_verbose_level)
+
+#define ABSL_LOG_INTERNAL_VLOG_EVERY_POW_2_IMPL(verbose_level)               \
+  switch (const int absl_logging_internal_verbose_level = (verbose_level))   \
+  case 0:                                                                    \
+  default:                                                                   \
+    ABSL_LOG_INTERNAL_CONDITION_INFO(                                        \
+        STATEFUL, ABSL_VLOG_IS_ON(absl_logging_internal_verbose_level))      \
+  (EveryPow2) ABSL_LOGGING_INTERNAL_LOG_INFO.InternalStream().WithVerbosity( \
+      absl_logging_internal_verbose_level)
+
+#define ABSL_LOG_INTERNAL_VLOG_EVERY_N_SEC_IMPL(verbose_level, n_seconds)  \
+  switch (const int absl_logging_internal_verbose_level = (verbose_level)) \
+  case 0:                                                                  \
+  default:                                                                 \
+    ABSL_LOG_INTERNAL_CONDITION_INFO(                                      \
+        STATEFUL, ABSL_VLOG_IS_ON(absl_logging_internal_verbose_level))    \
+  (EveryNSec, n_seconds) ABSL_LOGGING_INTERNAL_LOG_INFO.InternalStream()   \
+      .WithVerbosity(absl_logging_internal_verbose_level)
+
 #define ABSL_LOG_INTERNAL_LOG_IF_EVERY_N_IMPL(severity, condition, n)   \
   ABSL_LOG_INTERNAL_CONDITION##severity(STATEFUL, condition)(EveryN, n) \
       ABSL_LOGGING_INTERNAL_LOG##severity.InternalStream()
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/log_message.h b/contrib/restricted/abseil-cpp/absl/log/internal/log_message.h
index 46937728cb..4ecb8a1498 100644
--- a/contrib/restricted/abseil-cpp/absl/log/internal/log_message.h
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/log_message.h
@@ -40,7 +40,7 @@
 #include "absl/log/internal/nullguard.h"
 #include "absl/log/log_entry.h"
 #include "absl/log/log_sink.h"
-#include "absl/strings/internal/has_absl_stringify.h"
+#include "absl/strings/has_absl_stringify.h"
 #include "absl/strings/string_view.h"
 #include "absl/time/time.h"
 
@@ -170,15 +170,15 @@ class LogMessage {
 
   // Types that support `AbslStringify()` are serialized that way.
   template <typename T,
-            typename std::enable_if<
-                strings_internal::HasAbslStringify<T>::value, int>::type = 0>
+            typename std::enable_if<absl::HasAbslStringify<T>::value,
+                                    int>::type = 0>
   LogMessage& operator<<(const T& v) ABSL_ATTRIBUTE_NOINLINE;
 
   // Types that don't support `AbslStringify()` but do support streaming into a
   // `std::ostream&` are serialized that way.
   template <typename T,
-            typename std::enable_if<
-                !strings_internal::HasAbslStringify<T>::value, int>::type = 0>
+            typename std::enable_if<!absl::HasAbslStringify<T>::value,
+                                    int>::type = 0>
   LogMessage& operator<<(const T& v) ABSL_ATTRIBUTE_NOINLINE;
 
   // Note: We explicitly do not support `operator<<` for non-const references
@@ -283,8 +283,7 @@ class StringifySink final {
 
 // Note: the following is declared `ABSL_ATTRIBUTE_NOINLINE`
 template <typename T,
-          typename std::enable_if<strings_internal::HasAbslStringify<T>::value,
-                                  int>::type>
+          typename std::enable_if<absl::HasAbslStringify<T>::value, int>::type>
 LogMessage& LogMessage::operator<<(const T& v) {
   StringifySink sink(*this);
   // Replace with public API.
@@ -294,8 +293,7 @@ LogMessage& LogMessage::operator<<(const T& v) {
 
 // Note: the following is declared `ABSL_ATTRIBUTE_NOINLINE`
 template <typename T,
-          typename std::enable_if<!strings_internal::HasAbslStringify<T>::value,
-                                  int>::type>
+          typename std::enable_if<!absl::HasAbslStringify<T>::value, int>::type>
 LogMessage& LogMessage::operator<<(const T& v) {
   OstreamView view(*data_);
   view.stream() << log_internal::NullGuard<T>().Guard(v);
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/log_sink_set.cc b/contrib/restricted/abseil-cpp/absl/log/internal/log_sink_set.cc
index b7cbe36455..3d5c69952c 100644
--- a/contrib/restricted/abseil-cpp/absl/log/internal/log_sink_set.cc
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/log_sink_set.cc
@@ -35,6 +35,7 @@
 #include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/base/log_severity.h"
+#include "absl/base/no_destructor.h"
 #include "absl/base/thread_annotations.h"
 #include "absl/cleanup/cleanup.h"
 #include "absl/log/globals.h"
@@ -168,17 +169,16 @@ class GlobalLogSinkSet final {
 #if defined(__myriad2__) || defined(__Fuchsia__)
     // myriad2 and Fuchsia do not log to stderr by default.
 #else
-    static StderrLogSink* stderr_log_sink = new StderrLogSink;
-    AddLogSink(stderr_log_sink);
+    static absl::NoDestructor<StderrLogSink> stderr_log_sink;
+    AddLogSink(stderr_log_sink.get());
 #endif
 #ifdef __ANDROID__
-    static AndroidLogSink* android_log_sink = new AndroidLogSink;
-    AddLogSink(android_log_sink);
+    static absl::NoDestructor<AndroidLogSink> android_log_sink;
+    AddLogSink(android_log_sink.get());
 #endif
 #if defined(_WIN32)
-    static WindowsDebuggerLogSink* debugger_log_sink =
-        new WindowsDebuggerLogSink;
-    AddLogSink(debugger_log_sink);
+    static absl::NoDestructor<WindowsDebuggerLogSink> debugger_log_sink;
+    AddLogSink(debugger_log_sink.get());
 #endif  // !defined(_WIN32)
   }
 
@@ -268,7 +268,7 @@ class GlobalLogSinkSet final {
 
 // Returns reference to the global LogSinks set.
 GlobalLogSinkSet& GlobalSinks() {
-  static GlobalLogSinkSet* global_sinks = new GlobalLogSinkSet;
+  static absl::NoDestructor<GlobalLogSinkSet> global_sinks;
   return *global_sinks;
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/strip.h b/contrib/restricted/abseil-cpp/absl/log/internal/strip.h
index adc86ffdfa..f8d2786939 100644
--- a/contrib/restricted/abseil-cpp/absl/log/internal/strip.h
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/strip.h
@@ -37,7 +37,7 @@
 #define ABSL_LOGGING_INTERNAL_LOG_DFATAL \
   ::absl::log_internal::NullStreamMaybeFatal(::absl::kLogDebugFatal)
 #define ABSL_LOGGING_INTERNAL_LOG_LEVEL(severity) \
-  ::absl::log_internal::NullStreamMaybeFatal(log_internal_severity)
+  ::absl::log_internal::NullStreamMaybeFatal(absl_log_internal_severity)
 #define ABSL_LOG_INTERNAL_CHECK(failure_message) ABSL_LOGGING_INTERNAL_LOG_FATAL
 #define ABSL_LOG_INTERNAL_QCHECK(failure_message) \
   ABSL_LOGGING_INTERNAL_LOG_QFATAL
@@ -57,8 +57,9 @@
   ::absl::log_internal::LogMessageQuietlyFatal(__FILE__, __LINE__)
 #define ABSL_LOGGING_INTERNAL_LOG_DFATAL \
   ::absl::log_internal::LogMessage(__FILE__, __LINE__, ::absl::kLogDebugFatal)
-#define ABSL_LOGGING_INTERNAL_LOG_LEVEL(severity) \
-  ::absl::log_internal::LogMessage(__FILE__, __LINE__, log_internal_severity)
+#define ABSL_LOGGING_INTERNAL_LOG_LEVEL(severity)      \
+  ::absl::log_internal::LogMessage(__FILE__, __LINE__, \
+                                   absl_log_internal_severity)
 // These special cases dispatch to special-case constructors that allow us to
 // avoid an extra function call and shrink non-LTO binaries by a percent or so.
 #define ABSL_LOG_INTERNAL_CHECK(failure_message) \
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/vlog_config.cc b/contrib/restricted/abseil-cpp/absl/log/internal/vlog_config.cc
new file mode 100644
index 0000000000..b578850041
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/vlog_config.cc
@@ -0,0 +1,340 @@
+// Copyright 2022 The Abseil Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/log/internal/vlog_config.h"
+
+#include <stddef.h>
+
+#include <algorithm>
+#include <atomic>
+#include <functional>
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/const_init.h"
+#include "absl/base/internal/spinlock.h"
+#include "absl/base/no_destructor.h"
+#include "absl/base/optimization.h"
+#include "absl/base/thread_annotations.h"
+#include "absl/log/internal/fnmatch.h"
+#include "absl/memory/memory.h"
+#include "absl/strings/numbers.h"
+#include "absl/strings/str_split.h"
+#include "absl/strings/string_view.h"
+#include "absl/strings/strip.h"
+#include "absl/synchronization/mutex.h"
+#include "absl/types/optional.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace log_internal {
+
+namespace {
+bool ModuleIsPath(absl::string_view module_pattern) {
+#ifdef _WIN32
+  return module_pattern.find_first_of("/\\") != module_pattern.npos;
+#else
+  return module_pattern.find('/') != module_pattern.npos;
+#endif
+}
+}  // namespace
+
+bool VLogSite::SlowIsEnabled(int stale_v, int level) {
+  if (ABSL_PREDICT_TRUE(stale_v != kUninitialized)) {
+    // Because of the prerequisites to this function, we know that stale_v is
+    // either uninitialized or >= level. If it's not uninitialized, that means
+    // it must be >= level, thus we should log.
+    return true;
+  }
+  stale_v = log_internal::RegisterAndInitialize(this);
+  return ABSL_PREDICT_FALSE(stale_v >= level);
+}
+
+bool VLogSite::SlowIsEnabled0(int stale_v) { return SlowIsEnabled(stale_v, 0); }
+bool VLogSite::SlowIsEnabled1(int stale_v) { return SlowIsEnabled(stale_v, 1); }
+bool VLogSite::SlowIsEnabled2(int stale_v) { return SlowIsEnabled(stale_v, 2); }
+bool VLogSite::SlowIsEnabled3(int stale_v) { return SlowIsEnabled(stale_v, 3); }
+bool VLogSite::SlowIsEnabled4(int stale_v) { return SlowIsEnabled(stale_v, 4); }
+bool VLogSite::SlowIsEnabled5(int stale_v) { return SlowIsEnabled(stale_v, 5); }
+
+namespace {
+struct VModuleInfo final {
+  std::string module_pattern;
+  bool module_is_path;  // i.e. it contains a path separator.
+  int vlog_level;
+
+  // Allocates memory.
+  VModuleInfo(absl::string_view module_pattern_arg, bool module_is_path_arg,
+              int vlog_level_arg)
+      : module_pattern(std::string(module_pattern_arg)),
+        module_is_path(module_is_path_arg),
+        vlog_level(vlog_level_arg) {}
+};
+
+// `mutex` guards all of the data structures that aren't lock-free.
+// To avoid problems with the heap checker which calls into `VLOG`, `mutex` must
+// be a `SpinLock` that prevents fiber scheduling instead of a `Mutex`.
+ABSL_CONST_INIT absl::base_internal::SpinLock mutex(
+    absl::kConstInit, absl::base_internal::SCHEDULE_KERNEL_ONLY);
+
+// `GetUpdateSitesMutex()` serializes updates to all of the sites (i.e. those in
+// `site_list_head`) themselves.
+absl::Mutex* GetUpdateSitesMutex() {
+  // Chromium requires no global destructors, so we can't use the
+  // absl::kConstInit idiom since absl::Mutex as a non-trivial destructor.
+  static absl::NoDestructor<absl::Mutex> update_sites_mutex ABSL_ACQUIRED_AFTER(
+      mutex);
+  return update_sites_mutex.get();
+}
+
+ABSL_CONST_INIT int global_v ABSL_GUARDED_BY(mutex) = 0;
+// `site_list_head` is the head of a singly-linked list.  Traversal, insertion,
+// and reads are atomic, so no locks are required, but updates to existing
+// elements are guarded by `GetUpdateSitesMutex()`.
+ABSL_CONST_INIT std::atomic<VLogSite*> site_list_head{nullptr};
+ABSL_CONST_INIT std::vector<VModuleInfo>* vmodule_info ABSL_GUARDED_BY(mutex)
+    ABSL_PT_GUARDED_BY(mutex){nullptr};
+
+// Only used for lisp.
+ABSL_CONST_INIT std::vector<std::function<void()>>* update_callbacks
+    ABSL_GUARDED_BY(GetUpdateSitesMutex())
+        ABSL_PT_GUARDED_BY(GetUpdateSitesMutex()){nullptr};
+
+// Allocates memory.
+std::vector<VModuleInfo>& get_vmodule_info()
+    ABSL_EXCLUSIVE_LOCKS_REQUIRED(mutex) {
+  if (!vmodule_info) vmodule_info = new std::vector<VModuleInfo>;
+  return *vmodule_info;
+}
+
+// Does not allocate or take locks.
+int VLogLevel(absl::string_view file, const std::vector<VModuleInfo>* infos,
+              int current_global_v) {
+  // `infos` is null during a call to `VLOG` prior to setting `vmodule` (e.g. by
+  // parsing flags).  We can't allocate in `VLOG`, so we treat null as empty
+  // here and press on.
+  if (!infos || infos->empty()) return current_global_v;
+  // Get basename for file
+  absl::string_view basename = file;
+  {
+    const size_t sep = basename.rfind('/');
+    if (sep != basename.npos) {
+      basename.remove_prefix(sep + 1);
+#ifdef _WIN32
+    } else {
+      const size_t sep = basename.rfind('\\');
+      if (sep != basename.npos) basename.remove_prefix(sep + 1);
+#endif
+    }
+  }
+
+  absl::string_view stem = file, stem_basename = basename;
+  {
+    const size_t sep = stem_basename.find('.');
+    if (sep != stem_basename.npos) {
+      stem.remove_suffix(stem_basename.size() - sep);
+      stem_basename.remove_suffix(stem_basename.size() - sep);
+    }
+    if (absl::ConsumeSuffix(&stem_basename, "-inl")) {
+      stem.remove_suffix(absl::string_view("-inl").size());
+    }
+  }
+  for (const auto& info : *infos) {
+    if (info.module_is_path) {
+      // If there are any slashes in the pattern, try to match the full
+      // name.
+      if (FNMatch(info.module_pattern, stem)) {
+        return info.vlog_level == kUseFlag ? current_global_v : info.vlog_level;
+      }
+    } else if (FNMatch(info.module_pattern, stem_basename)) {
+      return info.vlog_level == kUseFlag ? current_global_v : info.vlog_level;
+    }
+  }
+
+  return current_global_v;
+}
+
+// Allocates memory.
+int AppendVModuleLocked(absl::string_view module_pattern, int log_level)
+    ABSL_EXCLUSIVE_LOCKS_REQUIRED(mutex) {
+  for (const auto& info : get_vmodule_info()) {
+    if (FNMatch(info.module_pattern, module_pattern)) {
+      // This is a memory optimization to avoid storing patterns that will never
+      // match due to exit early semantics. Primarily optimized for our own unit
+      // tests.
+      return info.vlog_level;
+    }
+  }
+  bool module_is_path = ModuleIsPath(module_pattern);
+  get_vmodule_info().emplace_back(std::string(module_pattern), module_is_path,
+                                  log_level);
+  return global_v;
+}
+
+// Allocates memory.
+int PrependVModuleLocked(absl::string_view module_pattern, int log_level)
+    ABSL_EXCLUSIVE_LOCKS_REQUIRED(mutex) {
+  absl::optional<int> old_log_level;
+  for (const auto& info : get_vmodule_info()) {
+    if (FNMatch(info.module_pattern, module_pattern)) {
+      old_log_level = info.vlog_level;
+      break;
+    }
+  }
+  bool module_is_path = ModuleIsPath(module_pattern);
+  auto iter = get_vmodule_info().emplace(get_vmodule_info().cbegin(),
+                                         std::string(module_pattern),
+                                         module_is_path, log_level);
+
+  // This is a memory optimization to avoid storing patterns that will never
+  // match due to exit early semantics. Primarily optimized for our own unit
+  // tests.
+  get_vmodule_info().erase(
+      std::remove_if(++iter, get_vmodule_info().end(),
+                     [module_pattern](const VModuleInfo& info) {
+                       return FNMatch(info.module_pattern, module_pattern);
+                     }),
+      get_vmodule_info().cend());
+  return old_log_level.value_or(global_v);
+}
+}  // namespace
+
+int VLogLevel(absl::string_view file) ABSL_LOCKS_EXCLUDED(mutex) {
+  absl::base_internal::SpinLockHolder l(&mutex);
+  return VLogLevel(file, vmodule_info, global_v);
+}
+
+int RegisterAndInitialize(VLogSite* v) ABSL_LOCKS_EXCLUDED(mutex) {
+  // std::memory_order_seq_cst is overkill in this function, but given that this
+  // path is intended to be slow, it's not worth the brain power to relax that.
+  VLogSite* h = site_list_head.load(std::memory_order_seq_cst);
+
+  VLogSite* old = nullptr;
+  if (v->next_.compare_exchange_strong(old, h, std::memory_order_seq_cst,
+                                       std::memory_order_seq_cst)) {
+    // Multiple threads may attempt to register this site concurrently.
+    // By successfully setting `v->next` this thread commits to being *the*
+    // thread that installs `v` in the list.
+    while (!site_list_head.compare_exchange_weak(
+        h, v, std::memory_order_seq_cst, std::memory_order_seq_cst)) {
+      v->next_.store(h, std::memory_order_seq_cst);
+    }
+  }
+
+  int old_v = VLogSite::kUninitialized;
+  int new_v = VLogLevel(v->file_);
+  // No loop, if someone else set this, we should respect their evaluation of
+  // `VLogLevel`. This may mean we return a stale `v`, but `v` itself will
+  // always arrive at the freshest value.  Otherwise, we could be writing a
+  // stale value and clobbering the fresher one.
+  if (v->v_.compare_exchange_strong(old_v, new_v, std::memory_order_seq_cst,
+                                    std::memory_order_seq_cst)) {
+    return new_v;
+  }
+  return old_v;
+}
+
+void UpdateVLogSites() ABSL_UNLOCK_FUNCTION(mutex)
+    ABSL_LOCKS_EXCLUDED(GetUpdateSitesMutex()) {
+  std::vector<VModuleInfo> infos = get_vmodule_info();
+  int current_global_v = global_v;
+  // We need to grab `GetUpdateSitesMutex()` before we release `mutex` to ensure
+  // that updates are not interleaved (resulting in an inconsistent final state)
+  // and to ensure that the final state in the sites matches the final state of
+  // `vmodule_info`. We unlock `mutex` to ensure that uninitialized sites don't
+  // have to wait on all updates in order to acquire `mutex` and initialize
+  // themselves.
+  absl::MutexLock ul(GetUpdateSitesMutex());
+  mutex.Unlock();
+  VLogSite* n = site_list_head.load(std::memory_order_seq_cst);
+  // Because sites are added to the list in the order they are executed, there
+  // tend to be clusters of entries with the same file.
+  const char* last_file = nullptr;
+  int last_file_level = 0;
+  while (n != nullptr) {
+    if (n->file_ != last_file) {
+      last_file = n->file_;
+      last_file_level = VLogLevel(n->file_, &infos, current_global_v);
+    }
+    n->v_.store(last_file_level, std::memory_order_seq_cst);
+    n = n->next_.load(std::memory_order_seq_cst);
+  }
+  if (update_callbacks) {
+    for (auto& cb : *update_callbacks) {
+      cb();
+    }
+  }
+}
+
+void UpdateVModule(absl::string_view vmodule)
+    ABSL_LOCKS_EXCLUDED(mutex, GetUpdateSitesMutex()) {
+  std::vector<std::pair<absl::string_view, int>> glob_levels;
+  for (absl::string_view glob_level : absl::StrSplit(vmodule, ',')) {
+    const size_t eq = glob_level.rfind('=');
+    if (eq == glob_level.npos) continue;
+    const absl::string_view glob = glob_level.substr(0, eq);
+    int level;
+    if (!absl::SimpleAtoi(glob_level.substr(eq + 1), &level)) continue;
+    glob_levels.emplace_back(glob, level);
+  }
+  mutex.Lock();  // Unlocked by UpdateVLogSites().
+  get_vmodule_info().clear();
+  for (const auto& it : glob_levels) {
+    const absl::string_view glob = it.first;
+    const int level = it.second;
+    AppendVModuleLocked(glob, level);
+  }
+  UpdateVLogSites();
+}
+
+int UpdateGlobalVLogLevel(int v)
+    ABSL_LOCKS_EXCLUDED(mutex, GetUpdateSitesMutex()) {
+  mutex.Lock();  // Unlocked by UpdateVLogSites().
+  const int old_global_v = global_v;
+  if (v == global_v) {
+    mutex.Unlock();
+    return old_global_v;
+  }
+  global_v = v;
+  UpdateVLogSites();
+  return old_global_v;
+}
+
+int PrependVModule(absl::string_view module_pattern, int log_level)
+    ABSL_LOCKS_EXCLUDED(mutex, GetUpdateSitesMutex()) {
+  mutex.Lock();  // Unlocked by UpdateVLogSites().
+  int old_v = PrependVModuleLocked(module_pattern, log_level);
+  UpdateVLogSites();
+  return old_v;
+}
+
+void OnVLogVerbosityUpdate(std::function<void()> cb)
+    ABSL_LOCKS_EXCLUDED(GetUpdateSitesMutex()) {
+  absl::MutexLock ul(GetUpdateSitesMutex());
+  if (!update_callbacks)
+    update_callbacks = new std::vector<std::function<void()>>;
+  update_callbacks->push_back(std::move(cb));
+}
+
+VLogSite* SetVModuleListHeadForTestOnly(VLogSite* v) {
+  return site_list_head.exchange(v, std::memory_order_seq_cst);
+}
+
+}  // namespace log_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/log/internal/vlog_config.h b/contrib/restricted/abseil-cpp/absl/log/internal/vlog_config.h
new file mode 100644
index 0000000000..b6e322c468
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/log/internal/vlog_config.h
@@ -0,0 +1,163 @@
+// Copyright 2022 The Abseil Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// vlog_config.h
+// -----------------------------------------------------------------------------
+//
+// This header file defines `VLogSite`, a public primitive that represents
+// a callsite for the `VLOG` family of macros and related libraries.
+// It also declares and defines multiple internal utilities used to implement
+// `VLOG`, such as `VLogSiteManager`.
+
+#ifndef ABSL_LOG_INTERNAL_VLOG_CONFIG_H_
+#define ABSL_LOG_INTERNAL_VLOG_CONFIG_H_
+
+// IWYU pragma: private, include "absl/log/log.h"
+
+#include <atomic>
+#include <cstdint>
+#include <functional>
+#include <limits>
+#include <type_traits>
+
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/optimization.h"
+#include "absl/base/thread_annotations.h"
+#include "absl/strings/string_view.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace log_internal {
+
+class SyntheticBinary;
+class VLogSite;
+
+int RegisterAndInitialize(VLogSite* v);
+void UpdateVLogSites();
+constexpr int kUseFlag = (std::numeric_limits<int16_t>::min)();
+
+// Represents a unique callsite for a `VLOG()` or `VLOG_IS_ON()` call.
+//
+// Libraries that provide `VLOG`-like functionality should use this to
+// efficiently handle --vmodule.
+//
+// VLogSite objects must not be destroyed until the program exits. Doing so will
+// probably yield nasty segfaults in VLogSiteManager::UpdateLogSites(). The
+// recommendation is to make all such objects function-local statics.
+class VLogSite final {
+ public:
+  // `f` must not be destroyed until the program exits.
+  explicit constexpr VLogSite(const char* f)
+      : file_(f), v_(kUninitialized), next_(nullptr) {}
+  VLogSite(const VLogSite&) = delete;
+  VLogSite& operator=(const VLogSite&) = delete;
+
+  // Inlining the function yields a ~3x performance improvement at the cost of a
+  // 1.5x code size increase at the call site.
+  // Takes locks but does not allocate memory.
+  ABSL_ATTRIBUTE_ALWAYS_INLINE
+  bool IsEnabled(int level) {
+    int stale_v = v_.load(std::memory_order_relaxed);
+    if (ABSL_PREDICT_TRUE(level > stale_v)) {
+      return false;
+    }
+
+    // We put everything other than the fast path, i.e. vlogging is initialized
+    // but not on, behind an out-of-line function to reduce code size.
+    // "level" is almost always a call-site constant, so we can save a bit
+    // of code space by special-casing for a few common levels.
+#if ABSL_HAVE_BUILTIN(__builtin_constant_p) || defined(__GNUC__)
+    if (__builtin_constant_p(level)) {
+      if (level == 0) return SlowIsEnabled0(stale_v);
+      if (level == 1) return SlowIsEnabled1(stale_v);
+      if (level == 2) return SlowIsEnabled2(stale_v);
+      if (level == 3) return SlowIsEnabled3(stale_v);
+      if (level == 4) return SlowIsEnabled4(stale_v);
+      if (level == 5) return SlowIsEnabled5(stale_v);
+    }
+#endif
+    return SlowIsEnabled(stale_v, level);
+  }
+
+ private:
+  friend int log_internal::RegisterAndInitialize(VLogSite* v);
+  friend void log_internal::UpdateVLogSites();
+  friend class log_internal::SyntheticBinary;
+  static constexpr int kUninitialized = (std::numeric_limits<int>::max)();
+
+  // SlowIsEnabled performs slower checks to determine whether a log site is
+  // enabled. Because it is expected to be called somewhat rarely
+  // (comparatively), it is not inlined to save on code size.
+  //
+  // Prerequisites to calling SlowIsEnabled:
+  //   1) stale_v is uninitialized OR
+  //   2) stale_v is initialized and >= level (meaning we must log).
+  // Takes locks but does not allocate memory.
+  ABSL_ATTRIBUTE_NOINLINE
+  bool SlowIsEnabled(int stale_v, int level);
+  ABSL_ATTRIBUTE_NOINLINE bool SlowIsEnabled0(int stale_v);
+  ABSL_ATTRIBUTE_NOINLINE bool SlowIsEnabled1(int stale_v);
+  ABSL_ATTRIBUTE_NOINLINE bool SlowIsEnabled2(int stale_v);
+  ABSL_ATTRIBUTE_NOINLINE bool SlowIsEnabled3(int stale_v);
+  ABSL_ATTRIBUTE_NOINLINE bool SlowIsEnabled4(int stale_v);
+  ABSL_ATTRIBUTE_NOINLINE bool SlowIsEnabled5(int stale_v);
+
+  // This object is too size-sensitive to use absl::string_view.
+  const char* const file_;
+  std::atomic<int> v_;
+  std::atomic<VLogSite*> next_;
+};
+static_assert(std::is_trivially_destructible<VLogSite>::value,
+              "VLogSite must be trivially destructible");
+
+// Returns the current verbose log level of `file`.
+// Does not allocate memory.
+int VLogLevel(absl::string_view file);
+
+// Registers a site `v` to get updated as `vmodule` and `v` change.  Also
+// initializes the site based on their current values, and returns that result.
+// Does not allocate memory.
+int RegisterAndInitialize(VLogSite* v);
+
+// Allocates memory.
+void UpdateVLogSites();
+
+// Completely overwrites the saved value of `vmodule`.
+// Allocates memory.
+void UpdateVModule(absl::string_view vmodule);
+
+// Updates the global verbosity level to `v` and returns the prior value.
+// Allocates memory.
+int UpdateGlobalVLogLevel(int v);
+
+// Atomically prepends `module_pattern=log_level` to the start of vmodule.
+// Returns the prior value for `module_pattern` if there was an exact match and
+// `global_v` otherwise.
+// Allocates memory.
+int PrependVModule(absl::string_view module_pattern, int log_level);
+
+// Registers `on_update` to be called whenever `v` or `vmodule` change.
+// Allocates memory.
+void OnVLogVerbosityUpdate(std::function<void()> cb);
+
+// Does not allocate memory.
+VLogSite* SetVModuleListHeadForTestOnly(VLogSite* v);
+
+}  // namespace log_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
+
+#endif  // ABSL_LOG_INTERNAL_VLOG_CONFIG_H_
diff --git a/contrib/restricted/abseil-cpp/absl/log/log.h b/contrib/restricted/abseil-cpp/absl/log/log.h
index 602b5acf07..b721b087cc 100644
--- a/contrib/restricted/abseil-cpp/absl/log/log.h
+++ b/contrib/restricted/abseil-cpp/absl/log/log.h
@@ -32,6 +32,8 @@
 // * The `QFATAL` pseudo-severity level is equivalent to `FATAL` but triggers
 //   quieter termination messages, e.g. without a full stack trace, and skips
 //   running registered error handlers.
+// * The `DFATAL` pseudo-severity level is defined as `FATAL` in debug mode and
+//   as `ERROR` otherwise.
 // Some preprocessor shenanigans are used to ensure that e.g. `LOG(INFO)` has
 // the same meaning even if a local symbol or preprocessor macro named `INFO` is
 // defined.  To specify a severity level using an expression instead of a
@@ -51,6 +53,14 @@
 //   * .NoPrefix()
 //     Omits the prefix from this line.  The prefix includes metadata about the
 //     logged data such as source code location and timestamp.
+//   * .WithVerbosity(int verbose_level)
+//     Sets the verbosity field of the logged message as if it was logged by
+//     `VLOG(verbose_level)`.  Unlike `VLOG`, this method does not affect
+//     evaluation of the statement when the specified `verbose_level` has been
+//     disabled.  The only effect is on `LogSink` implementations which make use
+//     of the `absl::LogSink::verbosity()` value.  The value
+//     `absl::LogEntry::kNoVerbosityLevel` can be specified to mark the message
+//     not verbose.
 //   * .WithTimestamp(absl::Time timestamp)
 //     Uses the specified timestamp instead of one collected at the time of
 //     execution.
@@ -188,6 +198,7 @@
 #define ABSL_LOG_LOG_H_
 
 #include "absl/log/internal/log_impl.h"
+#include "absl/log/vlog_is_on.h"  // IWYU pragma: export
 
 // LOG()
 //
@@ -211,11 +222,32 @@
 // terminate the program if `NDEBUG` is defined.
 #define DLOG(severity) ABSL_LOG_INTERNAL_DLOG_IMPL(_##severity)
 
+// `VLOG` uses numeric levels to provide verbose logging that can configured at
+// runtime, including at a per-module level.  `VLOG` statements are logged at
+// `INFO` severity if they are logged at all; the numeric levels are on a
+// different scale than the proper severity levels.  Positive levels are
+// disabled by default.  Negative levels should not be used.
+// Example:
+//
+//   VLOG(1) << "I print when you run the program with --v=1 or higher";
+//   VLOG(2) << "I print when you run the program with --v=2 or higher";
+//
+// See vlog_is_on.h for further documentation, including the usage of the
+// --vmodule flag to log at different levels in different source files.
+#define VLOG(severity) ABSL_LOG_INTERNAL_VLOG_IMPL(severity)
+
+// `DVLOG` behaves like `VLOG` in debug mode (i.e. `#ifndef NDEBUG`).
+// Otherwise, it compiles away and does nothing.
+#define DVLOG(severity) ABSL_LOG_INTERNAL_DVLOG_IMPL(severity)
+
 // `LOG_IF` and friends add a second argument which specifies a condition.  If
 // the condition is false, nothing is logged.
 // Example:
 //
 //   LOG_IF(INFO, num_cookies > 10) << "Got lots of cookies";
+//
+// There is no `VLOG_IF` because the order of evaluation of the arguments is
+// ambiguous and the alternate spelling with an `if`-statement is trivial.
 #define LOG_IF(severity, condition) \
   ABSL_LOG_INTERNAL_LOG_IF_IMPL(_##severity, condition)
 #define PLOG_IF(severity, condition) \
@@ -283,6 +315,15 @@
 #define DLOG_EVERY_N_SEC(severity, n_seconds) \
   ABSL_LOG_INTERNAL_DLOG_EVERY_N_SEC_IMPL(_##severity, n_seconds)
 
+#define VLOG_EVERY_N(severity, n) \
+  ABSL_LOG_INTERNAL_VLOG_EVERY_N_IMPL(severity, n)
+#define VLOG_FIRST_N(severity, n) \
+  ABSL_LOG_INTERNAL_VLOG_FIRST_N_IMPL(severity, n)
+#define VLOG_EVERY_POW_2(severity) \
+  ABSL_LOG_INTERNAL_VLOG_EVERY_POW_2_IMPL(severity)
+#define VLOG_EVERY_N_SEC(severity, n_seconds) \
+  ABSL_LOG_INTERNAL_VLOG_EVERY_N_SEC_IMPL(severity, n_seconds)
+
 // `LOG_IF_EVERY_N` and friends behave as the corresponding `LOG_EVERY_N`
 // but neither increment a counter nor log a message if condition is false (as
 // `LOG_IF`).
diff --git a/contrib/restricted/abseil-cpp/absl/log/log_entry.cc b/contrib/restricted/abseil-cpp/absl/log/log_entry.cc
index 19c3b3f1be..fe58a576b5 100644
--- a/contrib/restricted/abseil-cpp/absl/log/log_entry.cc
+++ b/contrib/restricted/abseil-cpp/absl/log/log_entry.cc
@@ -25,5 +25,17 @@ constexpr int LogEntry::kNoVerbosityLevel;
 constexpr int LogEntry::kNoVerboseLevel;
 #endif
 
+// https://github.com/abseil/abseil-cpp/issues/1465
+// CMake builds on Apple platforms error when libraries are empty.
+// Our CMake configuration can avoid this error on header-only libraries,
+// but since this library is conditionally empty, including a single
+// variable is an easy workaround.
+#ifdef __APPLE__
+namespace log_internal {
+extern const char kAvoidEmptyLogEntryLibraryWarning;
+const char kAvoidEmptyLogEntryLibraryWarning = 0;
+}  // namespace log_internal
+#endif  // __APPLE__
+
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/log/log_entry.h b/contrib/restricted/abseil-cpp/absl/log/log_entry.h
index 9e4ae8eb76..7a55dfe29e 100644
--- a/contrib/restricted/abseil-cpp/absl/log/log_entry.h
+++ b/contrib/restricted/abseil-cpp/absl/log/log_entry.h
@@ -96,7 +96,8 @@ class LogEntry final {
   // LogEntry::verbosity()
   //
   // Returns this entry's verbosity, or `kNoVerbosityLevel` for a non-verbose
-  // entry.  Verbosity control is not available outside of Google yet.
+  // entry. Taken from the argument to `VLOG` or from
+  // `LOG(...).WithVerbosity(...)`.
   int verbosity() const { return verbose_level_; }
 
   // LogEntry::timestamp()
diff --git a/contrib/restricted/abseil-cpp/absl/log/vlog_is_on.h b/contrib/restricted/abseil-cpp/absl/log/vlog_is_on.h
new file mode 100644
index 0000000000..7898651380
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/log/vlog_is_on.h
@@ -0,0 +1,72 @@
+// Copyright 2022 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: log/vlog_is_on.h
+// -----------------------------------------------------------------------------
+//
+// This header defines the `VLOG_IS_ON()` macro that controls the
+// variable-verbosity conditional logging.
+//
+// It's used by `VLOG` in log.h, or it can also be used directly like this:
+//
+//   if (VLOG_IS_ON(2)) {
+//     foo_server.RecomputeStatisticsExpensive();
+//     LOG(INFO) << foo_server.LastStatisticsAsString();
+//   }
+//
+// Each source file has an effective verbosity level that's a non-negative
+// integer computed from the `--vmodule` and `--v` flags.
+// `VLOG_IS_ON(n)` is true, and `VLOG(n)` logs, if that effective verbosity
+// level is greater than or equal to `n`.
+//
+// `--vmodule` takes a comma-delimited list of key=value pairs.  Each key is a
+// pattern matched against filenames, and the values give the effective severity
+// level applied to matching files.  '?' and '*' characters in patterns are
+// interpreted as single-character and zero-or-more-character wildcards.
+// Patterns including a slash character are matched against full pathnames,
+// while those without are matched against basenames only.  One suffix (i.e. the
+// last . and everything after it) is stripped from each filename prior to
+// matching, as is the special suffix "-inl".
+//
+// Files are matched against globs in `--vmodule` in order, and the first match
+// determines the verbosity level.
+//
+// Files which do not match any pattern in `--vmodule` use the value of `--v` as
+// their effective verbosity level.  The default is 0.
+//
+// SetVLOGLevel helper function is provided to do limited dynamic control over
+// V-logging by appending to `--vmodule`. Because these go at the beginning of
+// the list, they take priority over any globs previously added.
+//
+// Resetting --vmodule will override all previous modifications to `--vmodule`,
+// including via SetVLOGLevel.
+
+#ifndef ABSL_LOG_VLOG_IS_ON_H_
+#define ABSL_LOG_VLOG_IS_ON_H_
+
+#include "absl/log/absl_vlog_is_on.h"  // IWYU pragma: export
+
+// IWYU pragma: private, include "absl/log/log.h"
+
+// Each VLOG_IS_ON call site gets its own VLogSite that registers with the
+// global linked list of sites to asynchronously update its verbosity level on
+// changes to --v or --vmodule. The verbosity can also be set by manually
+// calling SetVLOGLevel.
+//
+// VLOG_IS_ON is not async signal safe, but it is guaranteed not to allocate
+// new memory.
+#define VLOG_IS_ON(verbose_level) ABSL_VLOG_IS_ON(verbose_level)
+
+#endif  // ABSL_LOG_VLOG_IS_ON_H_
diff --git a/contrib/restricted/abseil-cpp/absl/log/ya.make b/contrib/restricted/abseil-cpp/absl/log/ya.make
index cb73fdb2b2..f35baf8a56 100644
--- a/contrib/restricted/abseil-cpp/absl/log/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/log/ya.make
@@ -35,12 +35,14 @@ SRCS(
     initialize.cc
     internal/check_op.cc
     internal/conditions.cc
+    internal/fnmatch.cc
     internal/globals.cc
     internal/log_format.cc
     internal/log_message.cc
     internal/log_sink_set.cc
     internal/nullguard.cc
     internal/proto.cc
+    internal/vlog_config.cc
     log_entry.cc
     log_sink.cc
 )
diff --git a/contrib/restricted/abseil-cpp/absl/memory/ya.make b/contrib/restricted/abseil-cpp/absl/memory/ya.make
index 2d3aab1c79..4f191bfa0b 100644
--- a/contrib/restricted/abseil-cpp/absl/memory/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/memory/ya.make
@@ -6,9 +6,9 @@ LICENSE(Apache-2.0)
 
 LICENSE_TEXTS(.yandex_meta/licenses.list.txt)
 
-VERSION(20230802.1)
+VERSION(20240116.0)
 
-ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20230802.1.tar.gz)
+ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20240116.0.tar.gz)
 
 PEERDIR(
     contrib/restricted/abseil-cpp/absl/meta
diff --git a/contrib/restricted/abseil-cpp/absl/meta/ya.make b/contrib/restricted/abseil-cpp/absl/meta/ya.make
index 39b472c0fa..8a0016666e 100644
--- a/contrib/restricted/abseil-cpp/absl/meta/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/meta/ya.make
@@ -6,9 +6,9 @@ LICENSE(Apache-2.0)
 
 LICENSE_TEXTS(.yandex_meta/licenses.list.txt)
 
-VERSION(20230802.1)
+VERSION(20240116.0)
 
-ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20230802.1.tar.gz)
+ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20240116.0.tar.gz)
 
 PEERDIR(
     contrib/restricted/abseil-cpp/absl/base
diff --git a/contrib/restricted/abseil-cpp/absl/numeric/bits.h b/contrib/restricted/abseil-cpp/absl/numeric/bits.h
index 5ed36f5296..c76454c8fb 100644
--- a/contrib/restricted/abseil-cpp/absl/numeric/bits.h
+++ b/contrib/restricted/abseil-cpp/absl/numeric/bits.h
@@ -49,9 +49,19 @@
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
-#if !(defined(__cpp_lib_bitops) && __cpp_lib_bitops >= 201907L)
 
-// rotating
+// https://github.com/llvm/llvm-project/issues/64544
+// libc++ had the wrong signature for std::rotl and std::rotr
+// prior to libc++ 18.0.
+//
+#if (defined(__cpp_lib_bitops) && __cpp_lib_bitops >= 201907L) &&     \
+    (!defined(_LIBCPP_VERSION) || _LIBCPP_VERSION >= 180000)
+using std::rotl;
+using std::rotr;
+
+#else
+
+// Rotating functions
 template <class T>
 ABSL_MUST_USE_RESULT constexpr
     typename std::enable_if<std::is_unsigned<T>::value, T>::type
@@ -66,6 +76,22 @@ ABSL_MUST_USE_RESULT constexpr
   return numeric_internal::RotateRight(x, s);
 }
 
+#endif
+
+// https://github.com/llvm/llvm-project/issues/64544
+// libc++ had the wrong signature for std::rotl and std::rotr
+// prior to libc++ 18.0.
+//
+#if (defined(__cpp_lib_bitops) && __cpp_lib_bitops >= 201907L)
+
+using std::countl_one;
+using std::countl_zero;
+using std::countr_one;
+using std::countr_zero;
+using std::popcount;
+
+#else
+
 // Counting functions
 //
 // While these functions are typically constexpr, on some platforms, they may
@@ -107,19 +133,18 @@ ABSL_INTERNAL_CONSTEXPR_POPCOUNT inline
     popcount(T x) noexcept {
   return numeric_internal::Popcount(x);
 }
-#else  // defined(__cpp_lib_bitops) && __cpp_lib_bitops >= 201907L
-
-using std::countl_one;
-using std::countl_zero;
-using std::countr_one;
-using std::countr_zero;
-using std::popcount;
-using std::rotl;
-using std::rotr;
 
 #endif
 
-#if !(defined(__cpp_lib_int_pow2) && __cpp_lib_int_pow2 >= 202002L)
+#if (defined(__cpp_lib_int_pow2) && __cpp_lib_int_pow2 >= 202002L)
+
+using std::bit_ceil;
+using std::bit_floor;
+using std::bit_width;
+using std::has_single_bit;
+
+#else
+
 // Returns: true if x is an integral power of two; false otherwise.
 template <class T>
 constexpr inline typename std::enable_if<std::is_unsigned<T>::value, bool>::type
@@ -162,12 +187,6 @@ ABSL_INTERNAL_CONSTEXPR_CLZ inline
   return has_single_bit(x) ? T{1} << (bit_width(x) - 1)
                            : numeric_internal::BitCeilNonPowerOf2(x);
 }
-#else  // defined(__cpp_lib_int_pow2) && __cpp_lib_int_pow2 >= 202002L
-
-using std::bit_ceil;
-using std::bit_floor;
-using std::bit_width;
-using std::has_single_bit;
 
 #endif
 
diff --git a/contrib/restricted/abseil-cpp/absl/status/internal/status_internal.cc b/contrib/restricted/abseil-cpp/absl/status/internal/status_internal.cc
new file mode 100644
index 0000000000..a91567549e
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/status/internal/status_internal.cc
@@ -0,0 +1,248 @@
+// Copyright 2023 The Abseil Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/status/internal/status_internal.h"
+
+#include <atomic>
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
+#include <cstring>
+#include <memory>
+#include <string>
+#include <utility>
+
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/macros.h"
+#include "absl/base/nullability.h"
+#include "absl/debugging/stacktrace.h"
+#include "absl/debugging/symbolize.h"
+#include "absl/memory/memory.h"
+#include "absl/status/status.h"
+#include "absl/status/status_payload_printer.h"
+#include "absl/strings/cord.h"
+#include "absl/strings/escaping.h"
+#include "absl/strings/str_cat.h"
+#include "absl/strings/str_format.h"
+#include "absl/strings/str_split.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/optional.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace status_internal {
+
+void StatusRep::Unref() const {
+  // Fast path: if ref==1, there is no need for a RefCountDec (since
+  // this is the only reference and therefore no other thread is
+  // allowed to be mucking with r).
+  if (ref_.load(std::memory_order_acquire) == 1 ||
+      ref_.fetch_sub(1, std::memory_order_acq_rel) - 1 == 0) {
+    delete this;
+  }
+}
+
+static absl::optional<size_t> FindPayloadIndexByUrl(
+    const Payloads* payloads, absl::string_view type_url) {
+  if (payloads == nullptr) return absl::nullopt;
+
+  for (size_t i = 0; i < payloads->size(); ++i) {
+    if ((*payloads)[i].type_url == type_url) return i;
+  }
+
+  return absl::nullopt;
+}
+
+absl::optional<absl::Cord> StatusRep::GetPayload(
+    absl::string_view type_url) const {
+  absl::optional<size_t> index =
+      status_internal::FindPayloadIndexByUrl(payloads_.get(), type_url);
+  if (index.has_value()) return (*payloads_)[index.value()].payload;
+
+  return absl::nullopt;
+}
+
+void StatusRep::SetPayload(absl::string_view type_url, absl::Cord payload) {
+  if (payloads_ == nullptr) {
+    payloads_ = absl::make_unique<status_internal::Payloads>();
+  }
+
+  absl::optional<size_t> index =
+      status_internal::FindPayloadIndexByUrl(payloads_.get(), type_url);
+  if (index.has_value()) {
+    (*payloads_)[index.value()].payload = std::move(payload);
+    return;
+  }
+
+  payloads_->push_back({std::string(type_url), std::move(payload)});
+}
+
+StatusRep::EraseResult StatusRep::ErasePayload(absl::string_view type_url) {
+  absl::optional<size_t> index =
+      status_internal::FindPayloadIndexByUrl(payloads_.get(), type_url);
+  if (!index.has_value()) return {false, Status::PointerToRep(this)};
+  payloads_->erase(payloads_->begin() + index.value());
+  if (payloads_->empty() && message_.empty()) {
+    // Special case: If this can be represented inlined, it MUST be inlined
+    // (== depends on this behavior).
+    EraseResult result = {true, Status::CodeToInlinedRep(code_)};
+    Unref();
+    return result;
+  }
+  return {true, Status::PointerToRep(this)};
+}
+
+void StatusRep::ForEachPayload(
+    absl::FunctionRef<void(absl::string_view, const absl::Cord&)> visitor)
+    const {
+  if (auto* payloads = payloads_.get()) {
+    bool in_reverse =
+        payloads->size() > 1 && reinterpret_cast<uintptr_t>(payloads) % 13 > 6;
+
+    for (size_t index = 0; index < payloads->size(); ++index) {
+      const auto& elem =
+          (*payloads)[in_reverse ? payloads->size() - 1 - index : index];
+
+#ifdef NDEBUG
+      visitor(elem.type_url, elem.payload);
+#else
+      // In debug mode invalidate the type url to prevent users from relying on
+      // this string lifetime.
+
+      // NOLINTNEXTLINE intentional extra conversion to force temporary.
+      visitor(std::string(elem.type_url), elem.payload);
+#endif  // NDEBUG
+    }
+  }
+}
+
+std::string StatusRep::ToString(StatusToStringMode mode) const {
+  std::string text;
+  absl::StrAppend(&text, absl::StatusCodeToString(code()), ": ", message());
+
+  const bool with_payload = (mode & StatusToStringMode::kWithPayload) ==
+                            StatusToStringMode::kWithPayload;
+
+  if (with_payload) {
+    status_internal::StatusPayloadPrinter printer =
+        status_internal::GetStatusPayloadPrinter();
+    this->ForEachPayload([&](absl::string_view type_url,
+                             const absl::Cord& payload) {
+      absl::optional<std::string> result;
+      if (printer) result = printer(type_url, payload);
+      absl::StrAppend(
+          &text, " [", type_url, "='",
+          result.has_value() ? *result : absl::CHexEscape(std::string(payload)),
+          "']");
+    });
+  }
+
+  return text;
+}
+
+bool StatusRep::operator==(const StatusRep& other) const {
+  assert(this != &other);
+  if (code_ != other.code_) return false;
+  if (message_ != other.message_) return false;
+  const status_internal::Payloads* this_payloads = payloads_.get();
+  const status_internal::Payloads* other_payloads = other.payloads_.get();
+
+  const status_internal::Payloads no_payloads;
+  const status_internal::Payloads* larger_payloads =
+      this_payloads ? this_payloads : &no_payloads;
+  const status_internal::Payloads* smaller_payloads =
+      other_payloads ? other_payloads : &no_payloads;
+  if (larger_payloads->size() < smaller_payloads->size()) {
+    std::swap(larger_payloads, smaller_payloads);
+  }
+  if ((larger_payloads->size() - smaller_payloads->size()) > 1) return false;
+  // Payloads can be ordered differently, so we can't just compare payload
+  // vectors.
+  for (const auto& payload : *larger_payloads) {
+
+    bool found = false;
+    for (const auto& other_payload : *smaller_payloads) {
+      if (payload.type_url == other_payload.type_url) {
+        if (payload.payload != other_payload.payload) {
+          return false;
+        }
+        found = true;
+        break;
+      }
+    }
+    if (!found) return false;
+  }
+  return true;
+}
+
+absl::Nonnull<StatusRep*> StatusRep::CloneAndUnref() const {
+  // Optimization: no need to create a clone if we already have a refcount of 1.
+  if (ref_.load(std::memory_order_acquire) == 1) {
+    // All StatusRep instances are heap allocated and mutable, therefore this
+    // const_cast will never cast away const from a stack instance.
+    //
+    // CloneAndUnref is the only method that doesn't involve an external cast to
+    // get a mutable StatusRep* from the uintptr_t rep stored in Status.
+    return const_cast<StatusRep*>(this);
+  }
+  std::unique_ptr<status_internal::Payloads> payloads;
+  if (payloads_) {
+    payloads = absl::make_unique<status_internal::Payloads>(*payloads_);
+  }
+  auto* new_rep = new StatusRep(code_, message_, std::move(payloads));
+  Unref();
+  return new_rep;
+}
+
+// Convert canonical code to a value known to this binary.
+absl::StatusCode MapToLocalCode(int value) {
+  absl::StatusCode code = static_cast<absl::StatusCode>(value);
+  switch (code) {
+    case absl::StatusCode::kOk:
+    case absl::StatusCode::kCancelled:
+    case absl::StatusCode::kUnknown:
+    case absl::StatusCode::kInvalidArgument:
+    case absl::StatusCode::kDeadlineExceeded:
+    case absl::StatusCode::kNotFound:
+    case absl::StatusCode::kAlreadyExists:
+    case absl::StatusCode::kPermissionDenied:
+    case absl::StatusCode::kResourceExhausted:
+    case absl::StatusCode::kFailedPrecondition:
+    case absl::StatusCode::kAborted:
+    case absl::StatusCode::kOutOfRange:
+    case absl::StatusCode::kUnimplemented:
+    case absl::StatusCode::kInternal:
+    case absl::StatusCode::kUnavailable:
+    case absl::StatusCode::kDataLoss:
+    case absl::StatusCode::kUnauthenticated:
+      return code;
+    default:
+      return absl::StatusCode::kUnknown;
+  }
+}
+
+absl::Nonnull<std::string*> MakeCheckFailString(
+    absl::Nonnull<const absl::Status*> status,
+    absl::Nonnull<const char*> prefix) {
+  return new std::string(
+      absl::StrCat(prefix, " (",
+                   status->ToString(StatusToStringMode::kWithEverything), ")"));
+}
+
+}  // namespace status_internal
+
+ABSL_NAMESPACE_END
+}  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/status/internal/status_internal.h b/contrib/restricted/abseil-cpp/absl/status/internal/status_internal.h
index 6198e726b3..c9f4383272 100644
--- a/contrib/restricted/abseil-cpp/absl/status/internal/status_internal.h
+++ b/contrib/restricted/abseil-cpp/absl/status/internal/status_internal.h
@@ -14,13 +14,19 @@
 #ifndef ABSL_STATUS_INTERNAL_STATUS_INTERNAL_H_
 #define ABSL_STATUS_INTERNAL_STATUS_INTERNAL_H_
 
+#include <atomic>
+#include <cstdint>
 #include <memory>
 #include <string>
 #include <utility>
 
 #include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/nullability.h"
 #include "absl/container/inlined_vector.h"
 #include "absl/strings/cord.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/optional.h"
 
 #ifndef SWIG
 // Disabled for SWIG as it doesn't parse attributes correctly.
@@ -32,9 +38,9 @@ ABSL_NAMESPACE_BEGIN
 // TODO(b/176172494): ABSL_MUST_USE_RESULT should expand to the more strict
 // [[nodiscard]]. For now, just use [[nodiscard]] directly when it is available.
 #if ABSL_HAVE_CPP_ATTRIBUTE(nodiscard)
-class [[nodiscard]] Status;
+class [[nodiscard]] ABSL_ATTRIBUTE_TRIVIAL_ABI Status;
 #else
-class ABSL_MUST_USE_RESULT Status;
+class ABSL_MUST_USE_RESULT ABSL_ATTRIBUTE_TRIVIAL_ABI Status;
 #endif
 ABSL_NAMESPACE_END
 }  // namespace absl
@@ -44,6 +50,7 @@ namespace absl {
 ABSL_NAMESPACE_BEGIN
 
 enum class StatusCode : int;
+enum class StatusToStringMode : int;
 
 namespace status_internal {
 
@@ -56,22 +63,54 @@ struct Payload {
 using Payloads = absl::InlinedVector<Payload, 1>;
 
 // Reference-counted representation of Status data.
-struct StatusRep {
+class StatusRep {
+ public:
   StatusRep(absl::StatusCode code_arg, absl::string_view message_arg,
             std::unique_ptr<status_internal::Payloads> payloads_arg)
-      : ref(int32_t{1}),
-        code(code_arg),
-        message(message_arg),
-        payloads(std::move(payloads_arg)) {}
-
-  std::atomic<int32_t> ref;
-  absl::StatusCode code;
+      : ref_(int32_t{1}),
+        code_(code_arg),
+        message_(message_arg),
+        payloads_(std::move(payloads_arg)) {}
+
+  absl::StatusCode code() const { return code_; }
+  const std::string& message() const { return message_; }
+
+  // Ref and unref are const to allow access through a const pointer, and are
+  // used during copying operations.
+  void Ref() const { ref_.fetch_add(1, std::memory_order_relaxed); }
+  void Unref() const;
+
+  // Payload methods correspond to the same methods in absl::Status.
+  absl::optional<absl::Cord> GetPayload(absl::string_view type_url) const;
+  void SetPayload(absl::string_view type_url, absl::Cord payload);
+  struct EraseResult {
+    bool erased;
+    uintptr_t new_rep;
+  };
+  EraseResult ErasePayload(absl::string_view type_url);
+  void ForEachPayload(
+      absl::FunctionRef<void(absl::string_view, const absl::Cord&)> visitor)
+      const;
+
+  std::string ToString(StatusToStringMode mode) const;
+
+  bool operator==(const StatusRep& other) const;
+  bool operator!=(const StatusRep& other) const { return !(*this == other); }
+
+  // Returns an equivalent heap allocated StatusRep with refcount 1.
+  //
+  // `this` is not safe to be used after calling as it may have been deleted.
+  absl::Nonnull<StatusRep*> CloneAndUnref() const;
+
+ private:
+  mutable std::atomic<int32_t> ref_;
+  absl::StatusCode code_;
 
   // As an internal implementation detail, we guarantee that if status.message()
   // is non-empty, then the resulting string_view is null terminated.
   // This is required to implement 'StatusMessageAsCStr(...)'
-  std::string message;
-  std::unique_ptr<status_internal::Payloads> payloads;
+  std::string message_;
+  std::unique_ptr<status_internal::Payloads> payloads_;
 };
 
 absl::StatusCode MapToLocalCode(int value);
@@ -80,8 +119,10 @@ absl::StatusCode MapToLocalCode(int value);
 // suitable for output as an error message in assertion/`CHECK()` failures.
 //
 // This is an internal implementation detail for Abseil logging.
-std::string* MakeCheckFailString(const absl::Status* status,
-                                 const char* prefix);
+ABSL_ATTRIBUTE_PURE_FUNCTION
+absl::Nonnull<std::string*> MakeCheckFailString(
+    absl::Nonnull<const absl::Status*> status,
+    absl::Nonnull<const char*> prefix);
 
 }  // namespace status_internal
 
diff --git a/contrib/restricted/abseil-cpp/absl/status/internal/statusor_internal.h b/contrib/restricted/abseil-cpp/absl/status/internal/statusor_internal.h
index 49cead7a7f..5be94903b7 100644
--- a/contrib/restricted/abseil-cpp/absl/status/internal/statusor_internal.h
+++ b/contrib/restricted/abseil-cpp/absl/status/internal/statusor_internal.h
@@ -14,12 +14,15 @@
 #ifndef ABSL_STATUS_INTERNAL_STATUSOR_INTERNAL_H_
 #define ABSL_STATUS_INTERNAL_STATUSOR_INTERNAL_H_
 
+#include <cstdint>
 #include <type_traits>
 #include <utility>
 
 #include "absl/base/attributes.h"
+#include "absl/base/nullability.h"
 #include "absl/meta/type_traits.h"
 #include "absl/status/status.h"
+#include "absl/strings/string_view.h"
 #include "absl/utility/utility.h"
 
 namespace absl {
@@ -123,7 +126,7 @@ using IsForwardingAssignmentValid = absl::disjunction<
 class Helper {
  public:
   // Move type-agnostic error handling to the .cc.
-  static void HandleInvalidStatusCtorArg(Status*);
+  static void HandleInvalidStatusCtorArg(absl::Nonnull<Status*>);
   ABSL_ATTRIBUTE_NORETURN static void Crash(const absl::Status& status);
 };
 
@@ -131,7 +134,8 @@ class Helper {
 // the constructor.
 // This abstraction is here mostly for the gcc performance fix.
 template <typename T, typename... Args>
-ABSL_ATTRIBUTE_NONNULL(1) void PlacementNew(void* p, Args&&... args) {
+ABSL_ATTRIBUTE_NONNULL(1)
+void PlacementNew(absl::Nonnull<void*> p, Args&&... args) {
   new (p) T(std::forward<Args>(args)...);
 }
 
@@ -377,6 +381,53 @@ struct MoveAssignBase<T, false> {
 
 ABSL_ATTRIBUTE_NORETURN void ThrowBadStatusOrAccess(absl::Status status);
 
+// Used to introduce jitter into the output of printing functions for
+// `StatusOr` (i.e. `AbslStringify` and `operator<<`).
+class StringifyRandom {
+  enum BracesType {
+    kBareParens = 0,
+    kSpaceParens,
+    kBareBrackets,
+    kSpaceBrackets,
+  };
+
+  // Returns a random `BracesType` determined once per binary load.
+  static BracesType RandomBraces() {
+    static const BracesType kRandomBraces = static_cast<BracesType>(
+        (reinterpret_cast<uintptr_t>(&kRandomBraces) >> 4) % 4);
+    return kRandomBraces;
+  }
+
+ public:
+  static inline absl::string_view OpenBrackets() {
+    switch (RandomBraces()) {
+      case kBareParens:
+        return "(";
+      case kSpaceParens:
+        return "( ";
+      case kBareBrackets:
+        return "[";
+      case kSpaceBrackets:
+        return "[ ";
+    }
+    return "(";
+  }
+
+  static inline absl::string_view CloseBrackets() {
+    switch (RandomBraces()) {
+      case kBareParens:
+        return ")";
+      case kSpaceParens:
+        return " )";
+      case kBareBrackets:
+        return "]";
+      case kSpaceBrackets:
+        return " ]";
+    }
+    return ")";
+  }
+};
+
 }  // namespace internal_statusor
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/status/status.cc b/contrib/restricted/abseil-cpp/absl/status/status.cc
index 26e68294ac..4dd5ae06ce 100644
--- a/contrib/restricted/abseil-cpp/absl/status/status.cc
+++ b/contrib/restricted/abseil-cpp/absl/status/status.cc
@@ -15,23 +15,37 @@
 
 #include <errno.h>
 
-#include <cassert>
-#include <utility>
-
+#include <atomic>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+#include <memory>
+#include <ostream>
+#include <string>
+
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/base/internal/strerror.h"
 #include "absl/base/macros.h"
+#include "absl/base/no_destructor.h"
+#include "absl/base/nullability.h"
 #include "absl/debugging/stacktrace.h"
 #include "absl/debugging/symbolize.h"
-#include "absl/status/status_payload_printer.h"
-#include "absl/strings/escaping.h"
+#include "absl/status/internal/status_internal.h"
 #include "absl/strings/str_cat.h"
 #include "absl/strings/str_format.h"
 #include "absl/strings/str_split.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/optional.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
+static_assert(
+    alignof(status_internal::StatusRep) >= 4,
+    "absl::Status assumes it can use the bottom 2 bits of a StatusRep*.");
+
 std::string StatusCodeToString(StatusCode code) {
   switch (code) {
     case StatusCode::kOk:
@@ -77,146 +91,18 @@ std::ostream& operator<<(std::ostream& os, StatusCode code) {
   return os << StatusCodeToString(code);
 }
 
-namespace status_internal {
-
-static absl::optional<size_t> FindPayloadIndexByUrl(
-    const Payloads* payloads, absl::string_view type_url) {
-  if (payloads == nullptr) return absl::nullopt;
-
-  for (size_t i = 0; i < payloads->size(); ++i) {
-    if ((*payloads)[i].type_url == type_url) return i;
-  }
-
-  return absl::nullopt;
-}
-
-// Convert canonical code to a value known to this binary.
-absl::StatusCode MapToLocalCode(int value) {
-  absl::StatusCode code = static_cast<absl::StatusCode>(value);
-  switch (code) {
-    case absl::StatusCode::kOk:
-    case absl::StatusCode::kCancelled:
-    case absl::StatusCode::kUnknown:
-    case absl::StatusCode::kInvalidArgument:
-    case absl::StatusCode::kDeadlineExceeded:
-    case absl::StatusCode::kNotFound:
-    case absl::StatusCode::kAlreadyExists:
-    case absl::StatusCode::kPermissionDenied:
-    case absl::StatusCode::kResourceExhausted:
-    case absl::StatusCode::kFailedPrecondition:
-    case absl::StatusCode::kAborted:
-    case absl::StatusCode::kOutOfRange:
-    case absl::StatusCode::kUnimplemented:
-    case absl::StatusCode::kInternal:
-    case absl::StatusCode::kUnavailable:
-    case absl::StatusCode::kDataLoss:
-    case absl::StatusCode::kUnauthenticated:
-      return code;
-    default:
-      return absl::StatusCode::kUnknown;
-  }
-}
-}  // namespace status_internal
-
-absl::optional<absl::Cord> Status::GetPayload(
-    absl::string_view type_url) const {
-  const auto* payloads = GetPayloads();
-  absl::optional<size_t> index =
-      status_internal::FindPayloadIndexByUrl(payloads, type_url);
-  if (index.has_value()) return (*payloads)[index.value()].payload;
-
-  return absl::nullopt;
-}
-
-void Status::SetPayload(absl::string_view type_url, absl::Cord payload) {
-  if (ok()) return;
-
-  PrepareToModify();
-
-  status_internal::StatusRep* rep = RepToPointer(rep_);
-  if (!rep->payloads) {
-    rep->payloads = absl::make_unique<status_internal::Payloads>();
-  }
-
-  absl::optional<size_t> index =
-      status_internal::FindPayloadIndexByUrl(rep->payloads.get(), type_url);
-  if (index.has_value()) {
-    (*rep->payloads)[index.value()].payload = std::move(payload);
-    return;
-  }
-
-  rep->payloads->push_back({std::string(type_url), std::move(payload)});
-}
-
-bool Status::ErasePayload(absl::string_view type_url) {
-  absl::optional<size_t> index =
-      status_internal::FindPayloadIndexByUrl(GetPayloads(), type_url);
-  if (index.has_value()) {
-    PrepareToModify();
-    GetPayloads()->erase(GetPayloads()->begin() + index.value());
-    if (GetPayloads()->empty() && message().empty()) {
-      // Special case: If this can be represented inlined, it MUST be
-      // inlined (EqualsSlow depends on this behavior).
-      StatusCode c = static_cast<StatusCode>(raw_code());
-      Unref(rep_);
-      rep_ = CodeToInlinedRep(c);
-    }
-    return true;
-  }
-
-  return false;
-}
-
-void Status::ForEachPayload(
-    absl::FunctionRef<void(absl::string_view, const absl::Cord&)> visitor)
-    const {
-  if (auto* payloads = GetPayloads()) {
-    bool in_reverse =
-        payloads->size() > 1 && reinterpret_cast<uintptr_t>(payloads) % 13 > 6;
-
-    for (size_t index = 0; index < payloads->size(); ++index) {
-      const auto& elem =
-          (*payloads)[in_reverse ? payloads->size() - 1 - index : index];
-
-#ifdef NDEBUG
-      visitor(elem.type_url, elem.payload);
-#else
-      // In debug mode invalidate the type url to prevent users from relying on
-      // this string lifetime.
-
-      // NOLINTNEXTLINE intentional extra conversion to force temporary.
-      visitor(std::string(elem.type_url), elem.payload);
-#endif  // NDEBUG
-    }
-  }
-}
-
-const std::string* Status::EmptyString() {
-  static union EmptyString {
-    std::string str;
-    ~EmptyString() {}
-  } empty = {{}};
-  return &empty.str;
+absl::Nonnull<const std::string*> Status::EmptyString() {
+  static const absl::NoDestructor<std::string> kEmpty;
+  return kEmpty.get();
 }
 
 #ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
 constexpr const char Status::kMovedFromString[];
 #endif
 
-const std::string* Status::MovedFromString() {
-  static std::string* moved_from_string = new std::string(kMovedFromString);
-  return moved_from_string;
-}
-
-void Status::UnrefNonInlined(uintptr_t rep) {
-  status_internal::StatusRep* r = RepToPointer(rep);
-  // Fast path: if ref==1, there is no need for a RefCountDec (since
-  // this is the only reference and therefore no other thread is
-  // allowed to be mucking with r).
-  if (r->ref.load(std::memory_order_acquire) == 1 ||
-      r->ref.fetch_sub(1, std::memory_order_acq_rel) - 1 == 0) {
-    delete r;
-  }
+absl::Nonnull<const std::string*> Status::MovedFromString() {
+  static const absl::NoDestructor<std::string> kMovedFrom(kMovedFromString);
+  return kMovedFrom.get();
 }
 
 Status::Status(absl::StatusCode code, absl::string_view msg)
@@ -226,97 +112,20 @@ Status::Status(absl::StatusCode code, absl::string_view msg)
   }
 }
 
-int Status::raw_code() const {
-  if (IsInlined(rep_)) {
-    return static_cast<int>(InlinedRepToCode(rep_));
+absl::Nonnull<status_internal::StatusRep*> Status::PrepareToModify(
+    uintptr_t rep) {
+  if (IsInlined(rep)) {
+    return new status_internal::StatusRep(InlinedRepToCode(rep),
+                                          absl::string_view(), nullptr);
   }
-  status_internal::StatusRep* rep = RepToPointer(rep_);
-  return static_cast<int>(rep->code);
+  return RepToPointer(rep)->CloneAndUnref();
 }
 
-absl::StatusCode Status::code() const {
-  return status_internal::MapToLocalCode(raw_code());
-}
-
-void Status::PrepareToModify() {
-  ABSL_RAW_CHECK(!ok(), "PrepareToModify shouldn't be called on OK status.");
-  if (IsInlined(rep_)) {
-    rep_ = PointerToRep(new status_internal::StatusRep(
-        static_cast<absl::StatusCode>(raw_code()), absl::string_view(),
-        nullptr));
-    return;
+std::string Status::ToStringSlow(uintptr_t rep, StatusToStringMode mode) {
+  if (IsInlined(rep)) {
+    return absl::StrCat(absl::StatusCodeToString(InlinedRepToCode(rep)), ": ");
   }
-
-  uintptr_t rep_i = rep_;
-  status_internal::StatusRep* rep = RepToPointer(rep_);
-  if (rep->ref.load(std::memory_order_acquire) != 1) {
-    std::unique_ptr<status_internal::Payloads> payloads;
-    if (rep->payloads) {
-      payloads = absl::make_unique<status_internal::Payloads>(*rep->payloads);
-    }
-    status_internal::StatusRep* const new_rep = new status_internal::StatusRep(
-        rep->code, message(), std::move(payloads));
-    rep_ = PointerToRep(new_rep);
-    UnrefNonInlined(rep_i);
-  }
-}
-
-bool Status::EqualsSlow(const absl::Status& a, const absl::Status& b) {
-  if (IsInlined(a.rep_) != IsInlined(b.rep_)) return false;
-  if (a.message() != b.message()) return false;
-  if (a.raw_code() != b.raw_code()) return false;
-  if (a.GetPayloads() == b.GetPayloads()) return true;
-
-  const status_internal::Payloads no_payloads;
-  const status_internal::Payloads* larger_payloads =
-      a.GetPayloads() ? a.GetPayloads() : &no_payloads;
-  const status_internal::Payloads* smaller_payloads =
-      b.GetPayloads() ? b.GetPayloads() : &no_payloads;
-  if (larger_payloads->size() < smaller_payloads->size()) {
-    std::swap(larger_payloads, smaller_payloads);
-  }
-  if ((larger_payloads->size() - smaller_payloads->size()) > 1) return false;
-  // Payloads can be ordered differently, so we can't just compare payload
-  // vectors.
-  for (const auto& payload : *larger_payloads) {
-
-    bool found = false;
-    for (const auto& other_payload : *smaller_payloads) {
-      if (payload.type_url == other_payload.type_url) {
-        if (payload.payload != other_payload.payload) {
-          return false;
-        }
-        found = true;
-        break;
-      }
-    }
-    if (!found) return false;
-  }
-  return true;
-}
-
-std::string Status::ToStringSlow(StatusToStringMode mode) const {
-  std::string text;
-  absl::StrAppend(&text, absl::StatusCodeToString(code()), ": ", message());
-
-  const bool with_payload = (mode & StatusToStringMode::kWithPayload) ==
-                            StatusToStringMode::kWithPayload;
-
-  if (with_payload) {
-    status_internal::StatusPayloadPrinter printer =
-        status_internal::GetStatusPayloadPrinter();
-    this->ForEachPayload([&](absl::string_view type_url,
-                             const absl::Cord& payload) {
-      absl::optional<std::string> result;
-      if (printer) result = printer(type_url, payload);
-      absl::StrAppend(
-          &text, " [", type_url, "='",
-          result.has_value() ? *result : absl::CHexEscape(std::string(payload)),
-          "']");
-    });
-  }
-
-  return text;
+  return RepToPointer(rep)->ToString(mode);
 }
 
 std::ostream& operator<<(std::ostream& os, const Status& x) {
@@ -605,18 +414,7 @@ Status ErrnoToStatus(int error_number, absl::string_view message) {
                 MessageForErrnoToStatus(error_number, message));
 }
 
-namespace status_internal {
-
-std::string* MakeCheckFailString(const absl::Status* status,
-                                 const char* prefix) {
-  return new std::string(
-      absl::StrCat(prefix, " (",
-                   status->ToString(StatusToStringMode::kWithEverything), ")"));
-}
-
-}  // namespace status_internal
-
-const char* StatusMessageAsCStr(const Status& status) {
+absl::Nonnull<const char*> StatusMessageAsCStr(const Status& status) {
   // As an internal implementation detail, we guarantee that if status.message()
   // is non-empty, then the resulting string_view is null terminated.
   auto sv_message = status.message();
diff --git a/contrib/restricted/abseil-cpp/absl/status/status.h b/contrib/restricted/abseil-cpp/absl/status/status.h
index 595064c0f1..9ce16db961 100644
--- a/contrib/restricted/abseil-cpp/absl/status/status.h
+++ b/contrib/restricted/abseil-cpp/absl/status/status.h
@@ -51,10 +51,17 @@
 #ifndef ABSL_STATUS_STATUS_H_
 #define ABSL_STATUS_STATUS_H_
 
+#include <cassert>
+#include <cstdint>
 #include <ostream>
 #include <string>
 #include <utility>
 
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/macros.h"
+#include "absl/base/nullability.h"
+#include "absl/base/optimization.h"
 #include "absl/functional/function_ref.h"
 #include "absl/status/internal/status_internal.h"
 #include "absl/strings/cord.h"
@@ -421,7 +428,7 @@ inline StatusToStringMode& operator^=(StatusToStringMode& lhs,
 // Returned Status objects may not be ignored. status_internal.h has a forward
 // declaration of the form
 // class ABSL_MUST_USE_RESULT Status;
-class Status final {
+class ABSL_ATTRIBUTE_TRIVIAL_ABI Status final {
  public:
   // Constructors
 
@@ -516,6 +523,12 @@ class Status final {
   std::string ToString(
       StatusToStringMode mode = StatusToStringMode::kDefault) const;
 
+  // Support `absl::StrCat`, `absl::StrFormat`, etc.
+  template <typename Sink>
+  friend void AbslStringify(Sink& sink, const Status& status) {
+    sink.Append(status.ToString(StatusToStringMode::kWithEverything));
+  }
+
   // Status::IgnoreError()
   //
   // Ignores any errors. This method does nothing except potentially suppress
@@ -602,56 +615,57 @@ class Status final {
   // code, and an empty error message.
   explicit Status(absl::StatusCode code);
 
-  static void UnrefNonInlined(uintptr_t rep);
+  // Underlying constructor for status from a rep_.
+  explicit Status(uintptr_t rep) : rep_(rep) {}
+
   static void Ref(uintptr_t rep);
   static void Unref(uintptr_t rep);
 
   // REQUIRES: !ok()
-  // Ensures rep_ is not shared with any other Status.
-  void PrepareToModify();
-
-  const status_internal::Payloads* GetPayloads() const;
-  status_internal::Payloads* GetPayloads();
-
-  static bool EqualsSlow(const absl::Status& a, const absl::Status& b);
+  // Ensures rep is not inlined or shared with any other Status.
+  static absl::Nonnull<status_internal::StatusRep*> PrepareToModify(
+      uintptr_t rep);
 
   // MSVC 14.0 limitation requires the const.
   static constexpr const char kMovedFromString[] =
       "Status accessed after move.";
 
-  static const std::string* EmptyString();
-  static const std::string* MovedFromString();
+  static absl::Nonnull<const std::string*> EmptyString();
+  static absl::Nonnull<const std::string*> MovedFromString();
 
   // Returns whether rep contains an inlined representation.
   // See rep_ for details.
-  static bool IsInlined(uintptr_t rep);
+  static constexpr bool IsInlined(uintptr_t rep);
 
   // Indicates whether this Status was the rhs of a move operation. See rep_
   // for details.
-  static bool IsMovedFrom(uintptr_t rep);
-  static uintptr_t MovedFromRep();
+  static constexpr bool IsMovedFrom(uintptr_t rep);
+  static constexpr uintptr_t MovedFromRep();
 
   // Convert between error::Code and the inlined uintptr_t representation used
   // by rep_. See rep_ for details.
-  static uintptr_t CodeToInlinedRep(absl::StatusCode code);
-  static absl::StatusCode InlinedRepToCode(uintptr_t rep);
+  static constexpr uintptr_t CodeToInlinedRep(absl::StatusCode code);
+  static constexpr absl::StatusCode InlinedRepToCode(uintptr_t rep);
 
   // Converts between StatusRep* and the external uintptr_t representation used
   // by rep_. See rep_ for details.
   static uintptr_t PointerToRep(status_internal::StatusRep* r);
-  static status_internal::StatusRep* RepToPointer(uintptr_t r);
+  static absl::Nonnull<const status_internal::StatusRep*> RepToPointer(
+      uintptr_t r);
 
-  std::string ToStringSlow(StatusToStringMode mode) const;
+  static std::string ToStringSlow(uintptr_t rep, StatusToStringMode mode);
 
   // Status supports two different representations.
-  //  - When the low bit is off it is an inlined representation.
+  //  - When the low bit is set it is an inlined representation.
   //    It uses the canonical error space, no message or payload.
   //    The error code is (rep_ >> 2).
   //    The (rep_ & 2) bit is the "moved from" indicator, used in IsMovedFrom().
-  //  - When the low bit is on it is an external representation.
+  //  - When the low bit is off it is an external representation.
   //    In this case all the data comes from a heap allocated Rep object.
-  //    (rep_ - 1) is a status_internal::StatusRep* pointer to that structure.
+  //    rep_ is a status_internal::StatusRep* pointer to that structure.
   uintptr_t rep_;
+
+  friend class status_internal::StatusRep;
 };
 
 // OkStatus()
@@ -755,11 +769,11 @@ Status ErrnoToStatus(int error_number, absl::string_view message);
 // Implementation details follow
 //------------------------------------------------------------------------------
 
-inline Status::Status() : rep_(CodeToInlinedRep(absl::StatusCode::kOk)) {}
+inline Status::Status() : Status(absl::StatusCode::kOk) {}
 
-inline Status::Status(absl::StatusCode code) : rep_(CodeToInlinedRep(code)) {}
+inline Status::Status(absl::StatusCode code) : Status(CodeToInlinedRep(code)) {}
 
-inline Status::Status(const Status& x) : rep_(x.rep_) { Ref(rep_); }
+inline Status::Status(const Status& x) : Status(x.rep_) { Ref(rep_); }
 
 inline Status& Status::operator=(const Status& x) {
   uintptr_t old_rep = rep_;
@@ -771,7 +785,7 @@ inline Status& Status::operator=(const Status& x) {
   return *this;
 }
 
-inline Status::Status(Status&& x) noexcept : rep_(x.rep_) {
+inline Status::Status(Status&& x) noexcept : Status(x.rep_) {
   x.rep_ = MovedFromRep();
 }
 
@@ -803,15 +817,27 @@ inline bool Status::ok() const {
   return rep_ == CodeToInlinedRep(absl::StatusCode::kOk);
 }
 
+inline absl::StatusCode Status::code() const {
+  return status_internal::MapToLocalCode(raw_code());
+}
+
+inline int Status::raw_code() const {
+  if (IsInlined(rep_)) return static_cast<int>(InlinedRepToCode(rep_));
+  return static_cast<int>(RepToPointer(rep_)->code());
+}
+
 inline absl::string_view Status::message() const {
   return !IsInlined(rep_)
-             ? RepToPointer(rep_)->message
+             ? RepToPointer(rep_)->message()
              : (IsMovedFrom(rep_) ? absl::string_view(kMovedFromString)
                                   : absl::string_view());
 }
 
 inline bool operator==(const Status& lhs, const Status& rhs) {
-  return lhs.rep_ == rhs.rep_ || Status::EqualsSlow(lhs, rhs);
+  if (lhs.rep_ == rhs.rep_) return true;
+  if (Status::IsInlined(lhs.rep_)) return false;
+  if (Status::IsInlined(rhs.rep_)) return false;
+  return *Status::RepToPointer(lhs.rep_) == *Status::RepToPointer(rhs.rep_);
 }
 
 inline bool operator!=(const Status& lhs, const Status& rhs) {
@@ -819,7 +845,7 @@ inline bool operator!=(const Status& lhs, const Status& rhs) {
 }
 
 inline std::string Status::ToString(StatusToStringMode mode) const {
-  return ok() ? "OK" : ToStringSlow(mode);
+  return ok() ? "OK" : ToStringSlow(rep_, mode);
 }
 
 inline void Status::IgnoreError() const {
@@ -831,52 +857,68 @@ inline void swap(absl::Status& a, absl::Status& b) {
   swap(a.rep_, b.rep_);
 }
 
-inline const status_internal::Payloads* Status::GetPayloads() const {
-  return IsInlined(rep_) ? nullptr : RepToPointer(rep_)->payloads.get();
+inline absl::optional<absl::Cord> Status::GetPayload(
+    absl::string_view type_url) const {
+  if (IsInlined(rep_)) return absl::nullopt;
+  return RepToPointer(rep_)->GetPayload(type_url);
 }
 
-inline status_internal::Payloads* Status::GetPayloads() {
-  return IsInlined(rep_) ? nullptr : RepToPointer(rep_)->payloads.get();
+inline void Status::SetPayload(absl::string_view type_url, absl::Cord payload) {
+  if (ok()) return;
+  status_internal::StatusRep* rep = PrepareToModify(rep_);
+  rep->SetPayload(type_url, std::move(payload));
+  rep_ = PointerToRep(rep);
 }
 
-inline bool Status::IsInlined(uintptr_t rep) { return (rep & 1) == 0; }
-
-inline bool Status::IsMovedFrom(uintptr_t rep) {
-  return IsInlined(rep) && (rep & 2) != 0;
+inline bool Status::ErasePayload(absl::string_view type_url) {
+  if (IsInlined(rep_)) return false;
+  status_internal::StatusRep* rep = PrepareToModify(rep_);
+  auto res = rep->ErasePayload(type_url);
+  rep_ = res.new_rep;
+  return res.erased;
 }
 
-inline uintptr_t Status::MovedFromRep() {
-  return CodeToInlinedRep(absl::StatusCode::kInternal) | 2;
+inline void Status::ForEachPayload(
+    absl::FunctionRef<void(absl::string_view, const absl::Cord&)> visitor)
+    const {
+  if (IsInlined(rep_)) return;
+  RepToPointer(rep_)->ForEachPayload(visitor);
 }
 
-inline uintptr_t Status::CodeToInlinedRep(absl::StatusCode code) {
-  return static_cast<uintptr_t>(code) << 2;
+constexpr bool Status::IsInlined(uintptr_t rep) { return (rep & 1) != 0; }
+
+constexpr bool Status::IsMovedFrom(uintptr_t rep) { return (rep & 2) != 0; }
+
+constexpr uintptr_t Status::CodeToInlinedRep(absl::StatusCode code) {
+  return (static_cast<uintptr_t>(code) << 2) + 1;
 }
 
-inline absl::StatusCode Status::InlinedRepToCode(uintptr_t rep) {
-  assert(IsInlined(rep));
+constexpr absl::StatusCode Status::InlinedRepToCode(uintptr_t rep) {
+  ABSL_ASSERT(IsInlined(rep));
   return static_cast<absl::StatusCode>(rep >> 2);
 }
 
-inline status_internal::StatusRep* Status::RepToPointer(uintptr_t rep) {
+constexpr uintptr_t Status::MovedFromRep() {
+  return CodeToInlinedRep(absl::StatusCode::kInternal) | 2;
+}
+
+inline absl::Nonnull<const status_internal::StatusRep*> Status::RepToPointer(
+    uintptr_t rep) {
   assert(!IsInlined(rep));
-  return reinterpret_cast<status_internal::StatusRep*>(rep - 1);
+  return reinterpret_cast<const status_internal::StatusRep*>(rep);
 }
 
-inline uintptr_t Status::PointerToRep(status_internal::StatusRep* rep) {
-  return reinterpret_cast<uintptr_t>(rep) + 1;
+inline uintptr_t Status::PointerToRep(
+    absl::Nonnull<status_internal::StatusRep*> rep) {
+  return reinterpret_cast<uintptr_t>(rep);
 }
 
 inline void Status::Ref(uintptr_t rep) {
-  if (!IsInlined(rep)) {
-    RepToPointer(rep)->ref.fetch_add(1, std::memory_order_relaxed);
-  }
+  if (!IsInlined(rep)) RepToPointer(rep)->Ref();
 }
 
 inline void Status::Unref(uintptr_t rep) {
-  if (!IsInlined(rep)) {
-    UnrefNonInlined(rep);
-  }
+  if (!IsInlined(rep)) RepToPointer(rep)->Unref();
 }
 
 inline Status OkStatus() { return Status(); }
@@ -892,7 +934,7 @@ inline Status CancelledError() { return Status(absl::StatusCode::kCancelled); }
 // If the status's message is empty, the empty string is returned.
 //
 // StatusMessageAsCStr exists for C support. Use `status.message()` in C++.
-const char* StatusMessageAsCStr(
+absl::Nonnull<const char*> StatusMessageAsCStr(
     const Status& status ABSL_ATTRIBUTE_LIFETIME_BOUND);
 
 ABSL_NAMESPACE_END
diff --git a/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.cc b/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.cc
index a47aea11c2..98401e9072 100644
--- a/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.cc
+++ b/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.cc
@@ -13,9 +13,7 @@
 // limitations under the License.
 #include "absl/status/status_payload_printer.h"
 
-#include <atomic>
-
-#include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/atomic_hook.h"
 
 namespace absl {
diff --git a/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.h b/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.h
index 5e0937f67d..f22255e1c6 100644
--- a/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.h
+++ b/contrib/restricted/abseil-cpp/absl/status/status_payload_printer.h
@@ -16,6 +16,7 @@
 
 #include <string>
 
+#include "absl/base/nullability.h"
 #include "absl/strings/cord.h"
 #include "absl/strings/string_view.h"
 #include "absl/types/optional.h"
@@ -34,8 +35,8 @@ namespace status_internal {
 // NOTE: This is an internal API and the design is subject to change in the
 // future in a non-backward-compatible way. Since it's only meant for debugging
 // purpose, you should not rely on it in any critical logic.
-using StatusPayloadPrinter = absl::optional<std::string> (*)(absl::string_view,
-                                                             const absl::Cord&);
+using StatusPayloadPrinter = absl::Nullable<absl::optional<std::string> (*)(
+    absl::string_view, const absl::Cord&)>;
 
 // Sets the global payload printer. Only one printer should be set per process.
 // If multiple printers are set, it's undefined which one will be used.
diff --git a/contrib/restricted/abseil-cpp/absl/status/statusor.cc b/contrib/restricted/abseil-cpp/absl/status/statusor.cc
index 96642b340f..7e6b334c74 100644
--- a/contrib/restricted/abseil-cpp/absl/status/statusor.cc
+++ b/contrib/restricted/abseil-cpp/absl/status/statusor.cc
@@ -17,7 +17,10 @@
 #include <utility>
 
 #include "absl/base/call_once.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
+#include "absl/base/nullability.h"
+#include "absl/status/internal/statusor_internal.h"
 #include "absl/status/status.h"
 #include "absl/strings/str_cat.h"
 
@@ -52,7 +55,7 @@ BadStatusOrAccess& BadStatusOrAccess::operator=(BadStatusOrAccess&& other) {
 BadStatusOrAccess::BadStatusOrAccess(BadStatusOrAccess&& other)
     : status_(std::move(other.status_)) {}
 
-const char* BadStatusOrAccess::what() const noexcept {
+absl::Nonnull<const char*> BadStatusOrAccess::what() const noexcept {
   InitWhat();
   return what_.c_str();
 }
@@ -67,7 +70,7 @@ void BadStatusOrAccess::InitWhat() const {
 
 namespace internal_statusor {
 
-void Helper::HandleInvalidStatusCtorArg(absl::Status* status) {
+void Helper::HandleInvalidStatusCtorArg(absl::Nonnull<absl::Status*> status) {
   const char* kMessage =
       "An OK status is not a valid constructor argument to StatusOr<T>";
 #ifdef NDEBUG
diff --git a/contrib/restricted/abseil-cpp/absl/status/statusor.h b/contrib/restricted/abseil-cpp/absl/status/statusor.h
index 54c7ce023f..cd35e5b436 100644
--- a/contrib/restricted/abseil-cpp/absl/status/statusor.h
+++ b/contrib/restricted/abseil-cpp/absl/status/statusor.h
@@ -39,15 +39,20 @@
 #include <exception>
 #include <initializer_list>
 #include <new>
+#include <ostream>
 #include <string>
 #include <type_traits>
 #include <utility>
 
 #include "absl/base/attributes.h"
+#include "absl/base/nullability.h"
 #include "absl/base/call_once.h"
 #include "absl/meta/type_traits.h"
 #include "absl/status/internal/statusor_internal.h"
 #include "absl/status/status.h"
+#include "absl/strings/has_absl_stringify.h"
+#include "absl/strings/has_ostream_operator.h"
+#include "absl/strings/str_format.h"
 #include "absl/types/variant.h"
 #include "absl/utility/utility.h"
 
@@ -88,7 +93,7 @@ class BadStatusOrAccess : public std::exception {
   //
   // The pointer of this string is guaranteed to be valid until any non-const
   // function is invoked on the exception object.
-  const char* what() const noexcept override;
+  absl::Nonnull<const char*> what() const noexcept override;
 
   // BadStatusOrAccess::status()
   //
@@ -650,6 +655,41 @@ bool operator!=(const StatusOr<T>& lhs, const StatusOr<T>& rhs) {
   return !(lhs == rhs);
 }
 
+// Prints the `value` or the status in brackets to `os`.
+//
+// Requires `T` supports `operator<<`.  Do not rely on the output format which
+// may change without notice.
+template <typename T, typename std::enable_if<
+                          absl::HasOstreamOperator<T>::value, int>::type = 0>
+std::ostream& operator<<(std::ostream& os, const StatusOr<T>& status_or) {
+  if (status_or.ok()) {
+    os << status_or.value();
+  } else {
+    os << internal_statusor::StringifyRandom::OpenBrackets()
+       << status_or.status()
+       << internal_statusor::StringifyRandom::CloseBrackets();
+  }
+  return os;
+}
+
+// As above, but supports `StrCat`, `StrFormat`, etc.
+//
+// Requires `T` has `AbslStringify`.  Do not rely on the output format which
+// may change without notice.
+template <
+    typename Sink, typename T,
+    typename std::enable_if<absl::HasAbslStringify<T>::value, int>::type = 0>
+void AbslStringify(Sink& sink, const StatusOr<T>& status_or) {
+  if (status_or.ok()) {
+    absl::Format(&sink, "%v", status_or.value());
+  } else {
+    absl::Format(&sink, "%s%v%s",
+                 internal_statusor::StringifyRandom::OpenBrackets(),
+                 status_or.status(),
+                 internal_statusor::StringifyRandom::CloseBrackets());
+  }
+}
+
 //------------------------------------------------------------------------------
 // Implementation details for StatusOr<T>
 //------------------------------------------------------------------------------
@@ -750,13 +790,13 @@ T&& StatusOr<T>::operator*() && {
 }
 
 template <typename T>
-const T* StatusOr<T>::operator->() const {
+absl::Nonnull<const T*> StatusOr<T>::operator->() const {
   this->EnsureOk();
   return &this->data_;
 }
 
 template <typename T>
-T* StatusOr<T>::operator->() {
+absl::Nonnull<T*> StatusOr<T>::operator->() {
   this->EnsureOk();
   return &this->data_;
 }
diff --git a/contrib/restricted/abseil-cpp/absl/status/ya.make b/contrib/restricted/abseil-cpp/absl/status/ya.make
index f4a990c542..48ab349f07 100644
--- a/contrib/restricted/abseil-cpp/absl/status/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/status/ya.make
@@ -26,6 +26,7 @@ NO_COMPILER_WARNINGS()
 NO_UTIL()
 
 SRCS(
+    internal/status_internal.cc
     status.cc
     status_payload_printer.cc
 )
diff --git a/contrib/restricted/abseil-cpp/absl/strings/ascii.cc b/contrib/restricted/abseil-cpp/absl/strings/ascii.cc
index 16c9689961..5460b2c6dc 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/ascii.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/ascii.cc
@@ -15,8 +15,13 @@
 #include "absl/strings/ascii.h"
 
 #include <climits>
+#include <cstdint>
 #include <cstring>
 #include <string>
+#include <type_traits>
+
+#include "absl/base/config.h"
+#include "absl/base/nullability.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -157,8 +162,74 @@ ABSL_DLL const char kToUpper[256] = {
 };
 // clang-format on
 
+template <class T>
+static constexpr T BroadcastByte(unsigned char value) {
+  static_assert(std::is_integral<T>::value && sizeof(T) <= sizeof(uint64_t) &&
+                    std::is_unsigned<T>::value,
+                "only unsigned integers up to 64-bit allowed");
+  T result = value;
+  constexpr size_t result_bit_width = sizeof(result) * CHAR_BIT;
+  result |= result << ((CHAR_BIT << 0) & (result_bit_width - 1));
+  result |= result << ((CHAR_BIT << 1) & (result_bit_width - 1));
+  result |= result << ((CHAR_BIT << 2) & (result_bit_width - 1));
+  return result;
+}
+
+// Returns whether `c` is in the a-z/A-Z range (w.r.t. `ToUpper`).
+// Implemented by:
+//  1. Pushing the a-z/A-Z range to [SCHAR_MIN, SCHAR_MIN + 26).
+//  2. Comparing to SCHAR_MIN + 26.
+template <bool ToUpper>
+constexpr bool AsciiInAZRange(unsigned char c) {
+  constexpr unsigned char sub = (ToUpper ? 'a' : 'A') - SCHAR_MIN;
+  constexpr signed char threshold = SCHAR_MIN + 26;  // 26 = alphabet size.
+  // Using unsigned arithmetic as overflows/underflows are well defined.
+  unsigned char u = c - sub;
+  // Using signed cmp, as SIMD unsigned cmp isn't available in many platforms.
+  return static_cast<signed char>(u) < threshold;
+}
+
 template <bool ToUpper>
-constexpr void AsciiStrCaseFold(char* p, char* end) {
+static constexpr char* PartialAsciiStrCaseFold(absl::Nonnull<char*> p,
+                                               absl::Nonnull<char*> end) {
+  using vec_t = size_t;
+  const size_t n = static_cast<size_t>(end - p);
+
+  // SWAR algorithm: http://0x80.pl/notesen/2016-01-06-swar-swap-case.html
+  constexpr char ch_a = ToUpper ? 'a' : 'A', ch_z = ToUpper ? 'z' : 'Z';
+  char* const swar_end = p + (n / sizeof(vec_t)) * sizeof(vec_t);
+  while (p < swar_end) {
+    vec_t v = vec_t();
+
+    // memcpy the vector, but constexpr
+    for (size_t i = 0; i < sizeof(vec_t); ++i) {
+      v |= static_cast<vec_t>(static_cast<unsigned char>(p[i]))
+           << (i * CHAR_BIT);
+    }
+
+    constexpr unsigned int msb = 1u << (CHAR_BIT - 1);
+    const vec_t v_msb = v & BroadcastByte<vec_t>(msb);
+    const vec_t v_nonascii_mask = (v_msb << 1) - (v_msb >> (CHAR_BIT - 1));
+    const vec_t v_nonascii = v & v_nonascii_mask;
+    const vec_t v_ascii = v & ~v_nonascii_mask;
+    const vec_t a = v_ascii + BroadcastByte<vec_t>(msb - ch_a - 0),
+                z = v_ascii + BroadcastByte<vec_t>(msb - ch_z - 1);
+    v = v_nonascii | (v_ascii ^ ((a ^ z) & BroadcastByte<vec_t>(msb)) >> 2);
+
+    // memcpy the vector, but constexpr
+    for (size_t i = 0; i < sizeof(vec_t); ++i) {
+      p[i] = static_cast<char>(v >> (i * CHAR_BIT));
+    }
+
+    p += sizeof(v);
+  }
+
+  return p;
+}
+
+template <bool ToUpper>
+static constexpr void AsciiStrCaseFold(absl::Nonnull<char*> p,
+                                       absl::Nonnull<char*> end) {
   // The upper- and lowercase versions of ASCII characters differ by only 1 bit.
   // When we need to flip the case, we can xor with this bit to achieve the
   // desired result. Note that the choice of 'a' and 'A' here is arbitrary. We
@@ -166,16 +237,17 @@ constexpr void AsciiStrCaseFold(char* p, char* end) {
   // have the same single bit difference.
   constexpr unsigned char kAsciiCaseBitFlip = 'a' ^ 'A';
 
-  constexpr char ch_a = ToUpper ? 'a' : 'A';
-  constexpr char ch_z = ToUpper ? 'z' : 'Z';
-  for (; p < end; ++p) {
+  using vec_t = size_t;
+  // TODO(b/316380338): When FDO becomes able to vectorize these,
+  // revert this manual optimization and just leave the naive loop.
+  if (static_cast<size_t>(end - p) >= sizeof(vec_t)) {
+    p = ascii_internal::PartialAsciiStrCaseFold<ToUpper>(p, end);
+  }
+  while (p < end) {
     unsigned char v = static_cast<unsigned char>(*p);
-    // We use & instead of && to ensure this always stays branchless
-    // We use static_cast<int> to suppress -Wbitwise-instead-of-logical
-    bool is_in_range = static_cast<bool>(static_cast<int>(ch_a <= v) &
-                                         static_cast<int>(v <= ch_z));
-    v ^= is_in_range ? kAsciiCaseBitFlip : 0;
+    v ^= AsciiInAZRange<ToUpper>(v) ? kAsciiCaseBitFlip : 0;
     *p = static_cast<char>(v);
+    ++p;
   }
 }
 
@@ -205,17 +277,17 @@ static_assert(ValidateAsciiCasefold() == 0, "error in case conversion");
 
 }  // namespace ascii_internal
 
-void AsciiStrToLower(std::string* s) {
+void AsciiStrToLower(absl::Nonnull<std::string*> s) {
   char* p = &(*s)[0];  // Guaranteed to be valid for empty strings
   return ascii_internal::AsciiStrCaseFold<false>(p, p + s->size());
 }
 
-void AsciiStrToUpper(std::string* s) {
+void AsciiStrToUpper(absl::Nonnull<std::string*> s) {
   char* p = &(*s)[0];  // Guaranteed to be valid for empty strings
   return ascii_internal::AsciiStrCaseFold<true>(p, p + s->size());
 }
 
-void RemoveExtraAsciiWhitespace(std::string* str) {
+void RemoveExtraAsciiWhitespace(absl::Nonnull<std::string*> str) {
   auto stripped = StripAsciiWhitespace(*str);
 
   if (stripped.empty()) {
diff --git a/contrib/restricted/abseil-cpp/absl/strings/ascii.h b/contrib/restricted/abseil-cpp/absl/strings/ascii.h
index 42eadaea6c..c238f4de82 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/ascii.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/ascii.h
@@ -53,10 +53,12 @@
 #define ABSL_STRINGS_ASCII_H_
 
 #include <algorithm>
+#include <cstddef>
 #include <string>
 
 #include "absl/base/attributes.h"
 #include "absl/base/config.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/string_view.h"
 
 namespace absl {
@@ -165,7 +167,7 @@ inline char ascii_tolower(unsigned char c) {
 }
 
 // Converts the characters in `s` to lowercase, changing the contents of `s`.
-void AsciiStrToLower(std::string* s);
+void AsciiStrToLower(absl::Nonnull<std::string*> s);
 
 // Creates a lowercase string from a given absl::string_view.
 ABSL_MUST_USE_RESULT inline std::string AsciiStrToLower(absl::string_view s) {
@@ -183,7 +185,7 @@ inline char ascii_toupper(unsigned char c) {
 }
 
 // Converts the characters in `s` to uppercase, changing the contents of `s`.
-void AsciiStrToUpper(std::string* s);
+void AsciiStrToUpper(absl::Nonnull<std::string*> s);
 
 // Creates an uppercase string from a given absl::string_view.
 ABSL_MUST_USE_RESULT inline std::string AsciiStrToUpper(absl::string_view s) {
@@ -201,7 +203,7 @@ ABSL_MUST_USE_RESULT inline absl::string_view StripLeadingAsciiWhitespace(
 }
 
 // Strips in place whitespace from the beginning of the given string.
-inline void StripLeadingAsciiWhitespace(std::string* str) {
+inline void StripLeadingAsciiWhitespace(absl::Nonnull<std::string*> str) {
   auto it = std::find_if_not(str->begin(), str->end(), absl::ascii_isspace);
   str->erase(str->begin(), it);
 }
@@ -215,7 +217,7 @@ ABSL_MUST_USE_RESULT inline absl::string_view StripTrailingAsciiWhitespace(
 }
 
 // Strips in place whitespace from the end of the given string
-inline void StripTrailingAsciiWhitespace(std::string* str) {
+inline void StripTrailingAsciiWhitespace(absl::Nonnull<std::string*> str) {
   auto it = std::find_if_not(str->rbegin(), str->rend(), absl::ascii_isspace);
   str->erase(static_cast<size_t>(str->rend() - it));
 }
@@ -228,13 +230,13 @@ ABSL_MUST_USE_RESULT inline absl::string_view StripAsciiWhitespace(
 }
 
 // Strips in place whitespace from both ends of the given string
-inline void StripAsciiWhitespace(std::string* str) {
+inline void StripAsciiWhitespace(absl::Nonnull<std::string*> str) {
   StripTrailingAsciiWhitespace(str);
   StripLeadingAsciiWhitespace(str);
 }
 
 // Removes leading, trailing, and consecutive internal whitespace.
-void RemoveExtraAsciiWhitespace(std::string*);
+void RemoveExtraAsciiWhitespace(absl::Nonnull<std::string*> str);
 
 ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/strings/charconv.cc b/contrib/restricted/abseil-cpp/absl/strings/charconv.cc
index 778a1c75a5..0c9227f849 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/charconv.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/charconv.cc
@@ -16,12 +16,14 @@
 
 #include <algorithm>
 #include <cassert>
-#include <cmath>
-#include <cstring>
+#include <cstddef>
+#include <cstdint>
 #include <limits>
+#include <system_error>  // NOLINT(build/c++11)
 
 #include "absl/base/casts.h"
 #include "absl/base/config.h"
+#include "absl/base/nullability.h"
 #include "absl/numeric/bits.h"
 #include "absl/numeric/int128.h"
 #include "absl/strings/internal/charconv_bigint.h"
@@ -118,7 +120,7 @@ struct FloatTraits<double> {
   // Parsing a smaller N will produce something finite.
   static constexpr int kEiselLemireMaxExclusiveExp10 = 309;
 
-  static double MakeNan(const char* tagp) {
+  static double MakeNan(absl::Nonnull<const char*> tagp) {
 #if ABSL_HAVE_BUILTIN(__builtin_nan)
     // Use __builtin_nan() if available since it has a fix for
     // https://bugs.llvm.org/show_bug.cgi?id=37778
@@ -191,7 +193,7 @@ struct FloatTraits<float> {
   static constexpr int kEiselLemireMinInclusiveExp10 = -46 - 18;
   static constexpr int kEiselLemireMaxExclusiveExp10 = 39;
 
-  static float MakeNan(const char* tagp) {
+  static float MakeNan(absl::Nonnull<const char*> tagp) {
 #if ABSL_HAVE_BUILTIN(__builtin_nanf)
     // Use __builtin_nanf() if available since it has a fix for
     // https://bugs.llvm.org/show_bug.cgi?id=37778
@@ -343,7 +345,7 @@ int NormalizedShiftSize(int mantissa_width, int binary_exponent) {
 // `value` must be wider than the requested bit width.
 //
 // Returns the number of bits shifted.
-int TruncateToBitWidth(int bit_width, uint128* value) {
+int TruncateToBitWidth(int bit_width, absl::Nonnull<uint128*> value) {
   const int current_bit_width = BitWidth(*value);
   const int shift = current_bit_width - bit_width;
   *value >>= shift;
@@ -355,7 +357,7 @@ int TruncateToBitWidth(int bit_width, uint128* value) {
 // the appropriate double, and returns true.
 template <typename FloatType>
 bool HandleEdgeCase(const strings_internal::ParsedFloat& input, bool negative,
-                    FloatType* value) {
+                    absl::Nonnull<FloatType*> value) {
   if (input.type == strings_internal::FloatType::kNan) {
     // A bug in both clang < 7 and gcc would cause the compiler to optimize
     // away the buffer we are building below.  Declaring the buffer volatile
@@ -404,7 +406,8 @@ bool HandleEdgeCase(const strings_internal::ParsedFloat& input, bool negative,
 // number is stored in *value.
 template <typename FloatType>
 void EncodeResult(const CalculatedFloat& calculated, bool negative,
-                  absl::from_chars_result* result, FloatType* value) {
+                  absl::Nonnull<absl::from_chars_result*> result,
+                  absl::Nonnull<FloatType*> value) {
   if (calculated.exponent == kOverflow) {
     result->ec = std::errc::result_out_of_range;
     *value = negative ? -std::numeric_limits<FloatType>::max()
@@ -450,7 +453,7 @@ void EncodeResult(const CalculatedFloat& calculated, bool negative,
 // Zero and negative values of `shift` are accepted, in which case the word is
 // shifted left, as necessary.
 uint64_t ShiftRightAndRound(uint128 value, int shift, bool input_exact,
-                            bool* output_exact) {
+                            absl::Nonnull<bool*> output_exact) {
   if (shift <= 0) {
     *output_exact = input_exact;
     return static_cast<uint64_t>(value << -shift);
@@ -684,7 +687,8 @@ CalculatedFloat CalculateFromParsedDecimal(
 // this function returns false) is both fast and correct.
 template <typename FloatType>
 bool EiselLemire(const strings_internal::ParsedFloat& input, bool negative,
-                 FloatType* value, std::errc* ec) {
+                 absl::Nonnull<FloatType*> value,
+                 absl::Nonnull<std::errc*> ec) {
   uint64_t man = input.mantissa;
   int exp10 = input.exponent;
   if (exp10 < FloatTraits<FloatType>::kEiselLemireMinInclusiveExp10) {
@@ -857,7 +861,8 @@ bool EiselLemire(const strings_internal::ParsedFloat& input, bool negative,
 }
 
 template <typename FloatType>
-from_chars_result FromCharsImpl(const char* first, const char* last,
+from_chars_result FromCharsImpl(absl::Nonnull<const char*> first,
+                                absl::Nonnull<const char*> last,
                                 FloatType& value, chars_format fmt_flags) {
   from_chars_result result;
   result.ptr = first;  // overwritten on successful parse
@@ -943,12 +948,14 @@ from_chars_result FromCharsImpl(const char* first, const char* last,
 }
 }  // namespace
 
-from_chars_result from_chars(const char* first, const char* last, double& value,
+from_chars_result from_chars(absl::Nonnull<const char*> first,
+                             absl::Nonnull<const char*> last, double& value,
                              chars_format fmt) {
   return FromCharsImpl(first, last, value, fmt);
 }
 
-from_chars_result from_chars(const char* first, const char* last, float& value,
+from_chars_result from_chars(absl::Nonnull<const char*> first,
+                             absl::Nonnull<const char*> last, float& value,
                              chars_format fmt) {
   return FromCharsImpl(first, last, value, fmt);
 }
diff --git a/contrib/restricted/abseil-cpp/absl/strings/charconv.h b/contrib/restricted/abseil-cpp/absl/strings/charconv.h
index 111c7120de..be250902ad 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/charconv.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/charconv.h
@@ -18,6 +18,7 @@
 #include <system_error>  // NOLINT(build/c++11)
 
 #include "absl/base/config.h"
+#include "absl/base/nullability.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -44,7 +45,7 @@ enum class chars_format {
 // characters that were successfully parsed.  If none was found, `ptr` is set
 // to the `first` argument to from_chars.
 struct from_chars_result {
-  const char* ptr;
+  absl::Nonnull<const char*> ptr;
   std::errc ec;
 };
 
@@ -76,11 +77,13 @@ struct from_chars_result {
 // format that strtod() accepts, except that a "0x" prefix is NOT matched.
 // (In particular, in `hex` mode, the input "0xff" results in the largest
 // matching pattern "0".)
-absl::from_chars_result from_chars(const char* first, const char* last,
+absl::from_chars_result from_chars(absl::Nonnull<const char*> first,
+                                   absl::Nonnull<const char*> last,
                                    double& value,  // NOLINT
                                    chars_format fmt = chars_format::general);
 
-absl::from_chars_result from_chars(const char* first, const char* last,
+absl::from_chars_result from_chars(absl::Nonnull<const char*> first,
+                                   absl::Nonnull<const char*> last,
                                    float& value,  // NOLINT
                                    chars_format fmt = chars_format::general);
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/charset.h b/contrib/restricted/abseil-cpp/absl/strings/charset.h
new file mode 100644
index 0000000000..ff4e81a41f
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/strings/charset.h
@@ -0,0 +1,164 @@
+// Copyright 2022 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: charset.h
+// -----------------------------------------------------------------------------
+//
+// This file contains absl::CharSet, a fast, bit-vector set of 8-bit unsigned
+// characters.
+//
+// Instances can be initialized as constexpr constants. For example:
+//
+//   constexpr absl::CharSet kJustX = absl::CharSet::Char('x');
+//   constexpr absl::CharSet kMySymbols = absl::CharSet("$@!");
+//   constexpr absl::CharSet kLetters = absl::CharSet::Range('a', 'z');
+//
+// Multiple instances can be combined that still forms a constexpr expression.
+// For example:
+//
+//   constexpr absl::CharSet kLettersAndNumbers =
+//       absl::CharSet::Range('a', 'z') | absl::CharSet::Range('0', '9');
+//
+// Several pre-defined character classes are available that mirror the methods
+// from <cctype>. For example:
+//
+//   constexpr absl::CharSet kLettersAndWhitespace =
+//       absl::CharSet::AsciiAlphabet() | absl::CharSet::AsciiWhitespace();
+//
+// To check membership, use the .contains method, e.g.
+//
+//   absl::CharSet hex_letters("abcdef");
+//   hex_letters.contains('a');  // true
+//   hex_letters.contains('g');  // false
+
+#ifndef ABSL_STRINGS_CHARSET_H_
+#define ABSL_STRINGS_CHARSET_H_
+
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+
+#include "absl/base/macros.h"
+#include "absl/base/port.h"
+#include "absl/strings/string_view.h"
+
+namespace absl {
+
+class CharSet {
+ public:
+  constexpr CharSet() : m_() {}
+
+  // Initializes with a given string_view.
+  constexpr explicit CharSet(absl::string_view str) : m_() {
+    for (char c : str) {
+      SetChar(static_cast<unsigned char>(c));
+    }
+  }
+
+  constexpr bool contains(char c) const {
+    return ((m_[static_cast<unsigned char>(c) / 64] >>
+             (static_cast<unsigned char>(c) % 64)) &
+            0x1) == 0x1;
+  }
+
+  constexpr bool empty() const {
+    for (uint64_t c : m_) {
+      if (c != 0) return false;
+    }
+    return true;
+  }
+
+  // Containing only a single specified char.
+  static constexpr CharSet Char(char x) {
+    return CharSet(CharMaskForWord(x, 0), CharMaskForWord(x, 1),
+                   CharMaskForWord(x, 2), CharMaskForWord(x, 3));
+  }
+
+  // Containing all the chars in the closed interval [lo,hi].
+  static constexpr CharSet Range(char lo, char hi) {
+    return CharSet(RangeForWord(lo, hi, 0), RangeForWord(lo, hi, 1),
+                   RangeForWord(lo, hi, 2), RangeForWord(lo, hi, 3));
+  }
+
+  friend constexpr CharSet operator&(const CharSet& a, const CharSet& b) {
+    return CharSet(a.m_[0] & b.m_[0], a.m_[1] & b.m_[1], a.m_[2] & b.m_[2],
+                   a.m_[3] & b.m_[3]);
+  }
+
+  friend constexpr CharSet operator|(const CharSet& a, const CharSet& b) {
+    return CharSet(a.m_[0] | b.m_[0], a.m_[1] | b.m_[1], a.m_[2] | b.m_[2],
+                   a.m_[3] | b.m_[3]);
+  }
+
+  friend constexpr CharSet operator~(const CharSet& a) {
+    return CharSet(~a.m_[0], ~a.m_[1], ~a.m_[2], ~a.m_[3]);
+  }
+
+  // Mirrors the char-classifying predicates in <cctype>.
+  static constexpr CharSet AsciiUppercase() { return CharSet::Range('A', 'Z'); }
+  static constexpr CharSet AsciiLowercase() { return CharSet::Range('a', 'z'); }
+  static constexpr CharSet AsciiDigits() { return CharSet::Range('0', '9'); }
+  static constexpr CharSet AsciiAlphabet() {
+    return AsciiLowercase() | AsciiUppercase();
+  }
+  static constexpr CharSet AsciiAlphanumerics() {
+    return AsciiDigits() | AsciiAlphabet();
+  }
+  static constexpr CharSet AsciiHexDigits() {
+    return AsciiDigits() | CharSet::Range('A', 'F') | CharSet::Range('a', 'f');
+  }
+  static constexpr CharSet AsciiPrintable() {
+    return CharSet::Range(0x20, 0x7e);
+  }
+  static constexpr CharSet AsciiWhitespace() { return CharSet("\t\n\v\f\r "); }
+  static constexpr CharSet AsciiPunctuation() {
+    return AsciiPrintable() & ~AsciiWhitespace() & ~AsciiAlphanumerics();
+  }
+
+ private:
+  constexpr CharSet(uint64_t b0, uint64_t b1, uint64_t b2, uint64_t b3)
+      : m_{b0, b1, b2, b3} {}
+
+  static constexpr uint64_t RangeForWord(char lo, char hi, uint64_t word) {
+    return OpenRangeFromZeroForWord(static_cast<unsigned char>(hi) + 1, word) &
+           ~OpenRangeFromZeroForWord(static_cast<unsigned char>(lo), word);
+  }
+
+  // All the chars in the specified word of the range [0, upper).
+  static constexpr uint64_t OpenRangeFromZeroForWord(uint64_t upper,
+                                                     uint64_t word) {
+    return (upper <= 64 * word) ? 0
+           : (upper >= 64 * (word + 1))
+               ? ~static_cast<uint64_t>(0)
+               : (~static_cast<uint64_t>(0) >> (64 - upper % 64));
+  }
+
+  static constexpr uint64_t CharMaskForWord(char x, uint64_t word) {
+    return (static_cast<unsigned char>(x) / 64 == word)
+               ? (static_cast<uint64_t>(1)
+                  << (static_cast<unsigned char>(x) % 64))
+               : 0;
+  }
+
+  constexpr void SetChar(unsigned char c) {
+    m_[c / 64] |= static_cast<uint64_t>(1) << (c % 64);
+  }
+
+  uint64_t m_[4];
+};
+
+}  // namespace absl
+
+#endif  // ABSL_STRINGS_CHARSET_H_
diff --git a/contrib/restricted/abseil-cpp/absl/strings/cord.cc b/contrib/restricted/abseil-cpp/absl/strings/cord.cc
index 14976aef58..f67326fdef 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/cord.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/cord.cc
@@ -15,27 +15,33 @@
 #include "absl/strings/cord.h"
 
 #include <algorithm>
-#include <atomic>
+#include <cassert>
 #include <cstddef>
+#include <cstdint>
 #include <cstdio>
 #include <cstdlib>
+#include <cstring>
 #include <iomanip>
 #include <ios>
 #include <iostream>
 #include <limits>
+#include <memory>
 #include <ostream>
 #include <sstream>
-#include <type_traits>
-#include <unordered_set>
-#include <vector>
+#include <string>
+#include <utility>
 
-#include "absl/base/casts.h"
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/internal/endian.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/base/macros.h"
-#include "absl/base/port.h"
-#include "absl/container/fixed_array.h"
+#include "absl/base/optimization.h"
+#include "absl/base/nullability.h"
 #include "absl/container/inlined_vector.h"
+#include "absl/crc/crc32c.h"
 #include "absl/crc/internal/crc_cord_state.h"
+#include "absl/functional/function_ref.h"
 #include "absl/strings/cord_buffer.h"
 #include "absl/strings/escaping.h"
 #include "absl/strings/internal/cord_data_edge.h"
@@ -43,13 +49,14 @@
 #include "absl/strings/internal/cord_rep_btree.h"
 #include "absl/strings/internal/cord_rep_crc.h"
 #include "absl/strings/internal/cord_rep_flat.h"
-#include "absl/strings/internal/cordz_statistics.h"
-#include "absl/strings/internal/cordz_update_scope.h"
 #include "absl/strings/internal/cordz_update_tracker.h"
 #include "absl/strings/internal/resize_uninitialized.h"
+#include "absl/strings/match.h"
 #include "absl/strings/str_cat.h"
-#include "absl/strings/str_join.h"
 #include "absl/strings/string_view.h"
+#include "absl/strings/strip.h"
+#include "absl/types/optional.h"
+#include "absl/types/span.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -68,29 +75,21 @@ using ::absl::cord_internal::kMinFlatLength;
 using ::absl::cord_internal::kInlinedVectorSize;
 using ::absl::cord_internal::kMaxBytesToCopy;
 
-static void DumpNode(CordRep* rep, bool include_data, std::ostream* os,
-                     int indent = 0);
-static bool VerifyNode(CordRep* root, CordRep* start_node,
-                       bool full_validation);
-
-static inline CordRep* VerifyTree(CordRep* node) {
-  // Verification is expensive, so only do it in debug mode.
-  // Even in debug mode we normally do only light validation.
-  // If you are debugging Cord itself, you should define the
-  // macro EXTRA_CORD_VALIDATION, e.g. by adding
-  // --copt=-DEXTRA_CORD_VALIDATION to the blaze line.
-#ifdef EXTRA_CORD_VALIDATION
-  assert(node == nullptr || VerifyNode(node, node, /*full_validation=*/true));
-#else   // EXTRA_CORD_VALIDATION
-  assert(node == nullptr || VerifyNode(node, node, /*full_validation=*/false));
-#endif  // EXTRA_CORD_VALIDATION
-  static_cast<void>(&VerifyNode);
+static void DumpNode(absl::Nonnull<CordRep*> rep, bool include_data,
+                     absl::Nonnull<std::ostream*> os, int indent = 0);
+static bool VerifyNode(absl::Nonnull<CordRep*> root,
+                       absl::Nonnull<CordRep*> start_node);
 
+static inline absl::Nullable<CordRep*> VerifyTree(
+    absl::Nullable<CordRep*> node) {
+  assert(node == nullptr || VerifyNode(node, node));
+  static_cast<void>(&VerifyNode);
   return node;
 }
 
-static CordRepFlat* CreateFlat(const char* data, size_t length,
-                               size_t alloc_hint) {
+static absl::Nonnull<CordRepFlat*> CreateFlat(absl::Nonnull<const char*> data,
+                                              size_t length,
+                                              size_t alloc_hint) {
   CordRepFlat* flat = CordRepFlat::New(length + alloc_hint);
   flat->length = length;
   memcpy(flat->Data(), data, length);
@@ -99,7 +98,8 @@ static CordRepFlat* CreateFlat(const char* data, size_t length,
 
 // Creates a new flat or Btree out of the specified array.
 // The returned node has a refcount of 1.
-static CordRep* NewBtree(const char* data, size_t length, size_t alloc_hint) {
+static absl::Nonnull<CordRep*> NewBtree(absl::Nonnull<const char*> data,
+                                        size_t length, size_t alloc_hint) {
   if (length <= kMaxFlatLength) {
     return CreateFlat(data, length, alloc_hint);
   }
@@ -112,14 +112,16 @@ static CordRep* NewBtree(const char* data, size_t length, size_t alloc_hint) {
 
 // Create a new tree out of the specified array.
 // The returned node has a refcount of 1.
-static CordRep* NewTree(const char* data, size_t length, size_t alloc_hint) {
+static absl::Nullable<CordRep*> NewTree(absl::Nullable<const char*> data,
+                                        size_t length, size_t alloc_hint) {
   if (length == 0) return nullptr;
   return NewBtree(data, length, alloc_hint);
 }
 
 namespace cord_internal {
 
-void InitializeCordRepExternal(absl::string_view data, CordRepExternal* rep) {
+void InitializeCordRepExternal(absl::string_view data,
+                               absl::Nonnull<CordRepExternal*> rep) {
   assert(!data.empty());
   rep->length = data.size();
   rep->tag = EXTERNAL;
@@ -133,7 +135,7 @@ void InitializeCordRepExternal(absl::string_view data, CordRepExternal* rep) {
 // and not wasteful, we move the string into an external cord rep, preserving
 // the already allocated string contents.
 // Requires the provided string length to be larger than `kMaxInline`.
-static CordRep* CordRepFromString(std::string&& src) {
+static absl::Nonnull<CordRep*> CordRepFromString(std::string&& src) {
   assert(src.length() > cord_internal::kMaxInline);
   if (
       // String is short: copy data to avoid external block overhead.
@@ -165,12 +167,13 @@ static CordRep* CordRepFromString(std::string&& src) {
 constexpr unsigned char Cord::InlineRep::kMaxInline;
 #endif
 
-inline void Cord::InlineRep::set_data(const char* data, size_t n) {
+inline void Cord::InlineRep::set_data(absl::Nonnull<const char*> data,
+                                      size_t n) {
   static_assert(kMaxInline == 15, "set_data is hard-coded for a length of 15");
   data_.set_inline_data(data, n);
 }
 
-inline char* Cord::InlineRep::set_data(size_t n) {
+inline absl::Nonnull<char*> Cord::InlineRep::set_data(size_t n) {
   assert(n <= kMaxInline);
   ResetToEmpty();
   set_inline_size(n);
@@ -194,13 +197,13 @@ inline void Cord::InlineRep::remove_prefix(size_t n) {
 
 // Returns `rep` converted into a CordRepBtree.
 // Directly returns `rep` if `rep` is already a CordRepBtree.
-static CordRepBtree* ForceBtree(CordRep* rep) {
+static absl::Nonnull<CordRepBtree*> ForceBtree(CordRep* rep) {
   return rep->IsBtree()
              ? rep->btree()
              : CordRepBtree::Create(cord_internal::RemoveCrcNode(rep));
 }
 
-void Cord::InlineRep::AppendTreeToInlined(CordRep* tree,
+void Cord::InlineRep::AppendTreeToInlined(absl::Nonnull<CordRep*> tree,
                                           MethodIdentifier method) {
   assert(!is_tree());
   if (!data_.is_empty()) {
@@ -210,14 +213,16 @@ void Cord::InlineRep::AppendTreeToInlined(CordRep* tree,
   EmplaceTree(tree, method);
 }
 
-void Cord::InlineRep::AppendTreeToTree(CordRep* tree, MethodIdentifier method) {
+void Cord::InlineRep::AppendTreeToTree(absl::Nonnull<CordRep*> tree,
+                                       MethodIdentifier method) {
   assert(is_tree());
   const CordzUpdateScope scope(data_.cordz_info(), method);
   tree = CordRepBtree::Append(ForceBtree(data_.as_tree()), tree);
   SetTree(tree, scope);
 }
 
-void Cord::InlineRep::AppendTree(CordRep* tree, MethodIdentifier method) {
+void Cord::InlineRep::AppendTree(absl::Nonnull<CordRep*> tree,
+                                 MethodIdentifier method) {
   assert(tree != nullptr);
   assert(tree->length != 0);
   assert(!tree->IsCrc());
@@ -228,7 +233,7 @@ void Cord::InlineRep::AppendTree(CordRep* tree, MethodIdentifier method) {
   }
 }
 
-void Cord::InlineRep::PrependTreeToInlined(CordRep* tree,
+void Cord::InlineRep::PrependTreeToInlined(absl::Nonnull<CordRep*> tree,
                                            MethodIdentifier method) {
   assert(!is_tree());
   if (!data_.is_empty()) {
@@ -238,7 +243,7 @@ void Cord::InlineRep::PrependTreeToInlined(CordRep* tree,
   EmplaceTree(tree, method);
 }
 
-void Cord::InlineRep::PrependTreeToTree(CordRep* tree,
+void Cord::InlineRep::PrependTreeToTree(absl::Nonnull<CordRep*> tree,
                                         MethodIdentifier method) {
   assert(is_tree());
   const CordzUpdateScope scope(data_.cordz_info(), method);
@@ -246,7 +251,8 @@ void Cord::InlineRep::PrependTreeToTree(CordRep* tree,
   SetTree(tree, scope);
 }
 
-void Cord::InlineRep::PrependTree(CordRep* tree, MethodIdentifier method) {
+void Cord::InlineRep::PrependTree(absl::Nonnull<CordRep*> tree,
+                                  MethodIdentifier method) {
   assert(tree != nullptr);
   assert(tree->length != 0);
   assert(!tree->IsCrc());
@@ -261,8 +267,9 @@ void Cord::InlineRep::PrependTree(CordRep* tree, MethodIdentifier method) {
 // suitable leaf is found, the function will update the length field for all
 // nodes to account for the size increase. The append region address will be
 // written to region and the actual size increase will be written to size.
-static inline bool PrepareAppendRegion(CordRep* root, char** region,
-                                       size_t* size, size_t max_length) {
+static inline bool PrepareAppendRegion(
+    absl::Nonnull<CordRep*> root, absl::Nonnull<absl::Nullable<char*>*> region,
+    absl::Nonnull<size_t*> size, size_t max_length) {
   if (root->IsBtree() && root->refcount.IsOne()) {
     Span<char> span = root->btree()->GetAppendBuffer(max_length);
     if (!span.empty()) {
@@ -465,11 +472,11 @@ void Cord::InlineRep::AppendArray(absl::string_view src,
   CommitTree(root, rep, scope, method);
 }
 
-inline CordRep* Cord::TakeRep() const& {
+inline absl::Nonnull<CordRep*> Cord::TakeRep() const& {
   return CordRep::Ref(contents_.tree());
 }
 
-inline CordRep* Cord::TakeRep() && {
+inline absl::Nonnull<CordRep*> Cord::TakeRep() && {
   CordRep* rep = contents_.tree();
   contents_.clear();
   return rep;
@@ -527,7 +534,7 @@ inline void Cord::AppendImpl(C&& src) {
   contents_.AppendTree(rep, CordzUpdateTracker::kAppendCord);
 }
 
-static CordRep::ExtractResult ExtractAppendBuffer(CordRep* rep,
+static CordRep::ExtractResult ExtractAppendBuffer(absl::Nonnull<CordRep*> rep,
                                                   size_t min_capacity) {
   switch (rep->tag) {
     case cord_internal::BTREE:
@@ -573,13 +580,9 @@ CordBuffer Cord::GetAppendBufferSlowPath(size_t block_size, size_t capacity,
   return CreateAppendBuffer(contents_.data_, block_size, capacity);
 }
 
-void Cord::Append(const Cord& src) {
-  AppendImpl(src);
-}
+void Cord::Append(const Cord& src) { AppendImpl(src); }
 
-void Cord::Append(Cord&& src) {
-  AppendImpl(std::move(src));
-}
+void Cord::Append(Cord&& src) { AppendImpl(std::move(src)); }
 
 template <typename T, Cord::EnableIfString<T>>
 void Cord::Append(T&& src) {
@@ -778,8 +781,9 @@ int ClampResult(int memcmp_res) {
   return static_cast<int>(memcmp_res > 0) - static_cast<int>(memcmp_res < 0);
 }
 
-int CompareChunks(absl::string_view* lhs, absl::string_view* rhs,
-                  size_t* size_to_compare) {
+int CompareChunks(absl::Nonnull<absl::string_view*> lhs,
+                  absl::Nonnull<absl::string_view*> rhs,
+                  absl::Nonnull<size_t*> size_to_compare) {
   size_t compared_size = std::min(lhs->size(), rhs->size());
   assert(*size_to_compare >= compared_size);
   *size_to_compare -= compared_size;
@@ -877,7 +881,8 @@ void Cord::SetExpectedChecksum(uint32_t crc) {
   SetCrcCordState(std::move(state));
 }
 
-const crc_internal::CrcCordState* Cord::MaybeGetCrcCordState() const {
+absl::Nullable<const crc_internal::CrcCordState*> Cord::MaybeGetCrcCordState()
+    const {
   if (!contents_.is_tree() || !contents_.tree()->IsCrc()) {
     return nullptr;
   }
@@ -894,7 +899,8 @@ absl::optional<uint32_t> Cord::ExpectedChecksum() const {
 
 inline int Cord::CompareSlowPath(absl::string_view rhs, size_t compared_size,
                                  size_t size_to_compare) const {
-  auto advance = [](Cord::ChunkIterator* it, absl::string_view* chunk) {
+  auto advance = [](absl::Nonnull<Cord::ChunkIterator*> it,
+                    absl::Nonnull<absl::string_view*> chunk) {
     if (!chunk->empty()) return true;
     ++*it;
     if (it->bytes_remaining_ == 0) return false;
@@ -924,7 +930,8 @@ inline int Cord::CompareSlowPath(absl::string_view rhs, size_t compared_size,
 
 inline int Cord::CompareSlowPath(const Cord& rhs, size_t compared_size,
                                  size_t size_to_compare) const {
-  auto advance = [](Cord::ChunkIterator* it, absl::string_view* chunk) {
+  auto advance = [](absl::Nonnull<Cord::ChunkIterator*> it,
+                    absl::Nonnull<absl::string_view*> chunk) {
     if (!chunk->empty()) return true;
     ++*it;
     if (it->bytes_remaining_ == 0) return false;
@@ -1046,7 +1053,7 @@ Cord::operator std::string() const {
   return s;
 }
 
-void CopyCordToString(const Cord& src, std::string* dst) {
+void CopyCordToString(const Cord& src, absl::Nonnull<std::string*> dst) {
   if (!src.contents_.is_tree()) {
     src.contents_.CopyTo(dst);
   } else {
@@ -1055,7 +1062,7 @@ void CopyCordToString(const Cord& src, std::string* dst) {
   }
 }
 
-void Cord::CopyToArraySlowPath(char* dst) const {
+void Cord::CopyToArraySlowPath(absl::Nonnull<char*> dst) const {
   assert(contents_.is_tree());
   absl::string_view fragment;
   if (GetFlatAux(contents_.tree(), &fragment)) {
@@ -1165,6 +1172,194 @@ char Cord::operator[](size_t i) const {
   }
 }
 
+namespace {
+
+// Tests whether the sequence of chunks beginning at `position` starts with
+// `needle`.
+//
+// REQUIRES: remaining `absl::Cord` starting at `position` is greater than or
+// equal to `needle.size()`.
+bool IsSubstringInCordAt(absl::Cord::CharIterator position,
+                         absl::string_view needle) {
+  auto haystack_chunk = absl::Cord::ChunkRemaining(position);
+  while (true) {
+    // Precondition is that `absl::Cord::ChunkRemaining(position)` is not
+    // empty. This assert will trigger if that is not true.
+    assert(!haystack_chunk.empty());
+    auto min_length = std::min(haystack_chunk.size(), needle.size());
+    if (!absl::ConsumePrefix(&needle, haystack_chunk.substr(0, min_length))) {
+      return false;
+    }
+    if (needle.empty()) {
+      return true;
+    }
+    absl::Cord::Advance(&position, min_length);
+    haystack_chunk = absl::Cord::ChunkRemaining(position);
+  }
+}
+
+}  // namespace
+
+// A few options how this could be implemented:
+// (a) Flatten the Cord and find, i.e.
+//       haystack.Flatten().find(needle)
+//     For large 'haystack' (where Cord makes sense to be used), this copies
+//     the whole 'haystack' and can be slow.
+// (b) Use std::search, i.e.
+//       std::search(haystack.char_begin(), haystack.char_end(),
+//                   needle.begin(), needle.end())
+//     This avoids the copy, but compares one byte at a time, and branches a
+//     lot every time it has to advance. It is also not possible to use
+//     std::search as is, because CharIterator is only an input iterator, not a
+//     forward iterator.
+// (c) Use string_view::find in each fragment, and specifically handle fragment
+//     boundaries.
+//
+// This currently implements option (b).
+absl::Cord::CharIterator absl::Cord::FindImpl(CharIterator it,
+                                              absl::string_view needle) const {
+  // Ensure preconditions are met by callers first.
+
+  // Needle must not be empty.
+  assert(!needle.empty());
+  // Haystack must be at least as large as needle.
+  assert(it.chunk_iterator_.bytes_remaining_ >= needle.size());
+
+  // Cord is a sequence of chunks. To find `needle` we go chunk by chunk looking
+  // for the first char of needle, up until we have advanced `N` defined as
+  // `haystack.size() - needle.size()`. If we find the first char of needle at
+  // `P` and `P` is less than `N`, we then call `IsSubstringInCordAt` to
+  // see if this is the needle. If not, we advance to `P + 1` and try again.
+  while (it.chunk_iterator_.bytes_remaining_ >= needle.size()) {
+    auto haystack_chunk = Cord::ChunkRemaining(it);
+    assert(!haystack_chunk.empty());
+    // Look for the first char of `needle` in the current chunk.
+    auto idx = haystack_chunk.find(needle.front());
+    if (idx == absl::string_view::npos) {
+      // No potential match in this chunk, advance past it.
+      Cord::Advance(&it, haystack_chunk.size());
+      continue;
+    }
+    // We found the start of a potential match in the chunk. Advance the
+    // iterator and haystack chunk to the match the position.
+    Cord::Advance(&it, idx);
+    // Check if there is enough haystack remaining to actually have a match.
+    if (it.chunk_iterator_.bytes_remaining_ < needle.size()) {
+      break;
+    }
+    // Check if this is `needle`.
+    if (IsSubstringInCordAt(it, needle)) {
+      return it;
+    }
+    // No match, increment the iterator for the next attempt.
+    Cord::Advance(&it, 1);
+  }
+  // If we got here, we did not find `needle`.
+  return char_end();
+}
+
+absl::Cord::CharIterator absl::Cord::Find(absl::string_view needle) const {
+  if (needle.empty()) {
+    return char_begin();
+  }
+  if (needle.size() > size()) {
+    return char_end();
+  }
+  if (needle.size() == size()) {
+    return *this == needle ? char_begin() : char_end();
+  }
+  return FindImpl(char_begin(), needle);
+}
+
+namespace {
+
+// Tests whether the sequence of chunks beginning at `haystack` starts with the
+// sequence of chunks beginning at `needle_begin` and extending to `needle_end`.
+//
+// REQUIRES: remaining `absl::Cord` starting at `position` is greater than or
+// equal to `needle_end - needle_begin` and `advance`.
+bool IsSubcordInCordAt(absl::Cord::CharIterator haystack,
+                       absl::Cord::CharIterator needle_begin,
+                       absl::Cord::CharIterator needle_end) {
+  while (needle_begin != needle_end) {
+    auto haystack_chunk = absl::Cord::ChunkRemaining(haystack);
+    assert(!haystack_chunk.empty());
+    auto needle_chunk = absl::Cord::ChunkRemaining(needle_begin);
+    auto min_length = std::min(haystack_chunk.size(), needle_chunk.size());
+    if (haystack_chunk.substr(0, min_length) !=
+        needle_chunk.substr(0, min_length)) {
+      return false;
+    }
+    absl::Cord::Advance(&haystack, min_length);
+    absl::Cord::Advance(&needle_begin, min_length);
+  }
+  return true;
+}
+
+// Tests whether the sequence of chunks beginning at `position` starts with the
+// cord `needle`.
+//
+// REQUIRES: remaining `absl::Cord` starting at `position` is greater than or
+// equal to `needle.size()`.
+bool IsSubcordInCordAt(absl::Cord::CharIterator position,
+                       const absl::Cord& needle) {
+  return IsSubcordInCordAt(position, needle.char_begin(), needle.char_end());
+}
+
+}  // namespace
+
+absl::Cord::CharIterator absl::Cord::Find(const absl::Cord& needle) const {
+  if (needle.empty()) {
+    return char_begin();
+  }
+  const auto needle_size = needle.size();
+  if (needle_size > size()) {
+    return char_end();
+  }
+  if (needle_size == size()) {
+    return *this == needle ? char_begin() : char_end();
+  }
+  const auto needle_chunk = Cord::ChunkRemaining(needle.char_begin());
+  auto haystack_it = char_begin();
+  while (true) {
+    haystack_it = FindImpl(haystack_it, needle_chunk);
+    if (haystack_it == char_end() ||
+        haystack_it.chunk_iterator_.bytes_remaining_ < needle_size) {
+      break;
+    }
+    // We found the first chunk of `needle` at `haystack_it` but not the entire
+    // subcord. Advance past the first chunk and check for the remainder.
+    auto haystack_advanced_it = haystack_it;
+    auto needle_it = needle.char_begin();
+    Cord::Advance(&haystack_advanced_it, needle_chunk.size());
+    Cord::Advance(&needle_it, needle_chunk.size());
+    if (IsSubcordInCordAt(haystack_advanced_it, needle_it, needle.char_end())) {
+      return haystack_it;
+    }
+    Cord::Advance(&haystack_it, 1);
+    if (haystack_it.chunk_iterator_.bytes_remaining_ < needle_size) {
+      break;
+    }
+    if (haystack_it.chunk_iterator_.bytes_remaining_ == needle_size) {
+      // Special case, if there is exactly `needle_size` bytes remaining, the
+      // subcord is either at `haystack_it` or not at all.
+      if (IsSubcordInCordAt(haystack_it, needle)) {
+        return haystack_it;
+      }
+      break;
+    }
+  }
+  return char_end();
+}
+
+bool Cord::Contains(absl::string_view rhs) const {
+  return rhs.empty() || Find(rhs) != char_end();
+}
+
+bool Cord::Contains(const absl::Cord& rhs) const {
+  return rhs.empty() || Find(rhs) != char_end();
+}
+
 absl::string_view Cord::FlattenSlowPath() {
   assert(contents_.is_tree());
   size_t total_size = size();
@@ -1193,7 +1388,8 @@ absl::string_view Cord::FlattenSlowPath() {
   return absl::string_view(new_buffer, total_size);
 }
 
-/* static */ bool Cord::GetFlatAux(CordRep* rep, absl::string_view* fragment) {
+/* static */ bool Cord::GetFlatAux(absl::Nonnull<CordRep*> rep,
+                                   absl::Nonnull<absl::string_view*> fragment) {
   assert(rep != nullptr);
   if (rep->length == 0) {
     *fragment = absl::string_view();
@@ -1227,7 +1423,7 @@ absl::string_view Cord::FlattenSlowPath() {
 }
 
 /* static */ void Cord::ForEachChunkAux(
-    absl::cord_internal::CordRep* rep,
+    absl::Nonnull<absl::cord_internal::CordRep*> rep,
     absl::FunctionRef<void(absl::string_view)> callback) {
   assert(rep != nullptr);
   if (rep->length == 0) return;
@@ -1252,8 +1448,8 @@ absl::string_view Cord::FlattenSlowPath() {
   }
 }
 
-static void DumpNode(CordRep* rep, bool include_data, std::ostream* os,
-                     int indent) {
+static void DumpNode(absl::Nonnull<CordRep*> rep, bool include_data,
+                     absl::Nonnull<std::ostream*> os, int indent) {
   const int kIndentStep = 1;
   absl::InlinedVector<CordRep*, kInlinedVectorSize> stack;
   absl::InlinedVector<int, kInlinedVectorSize> indents;
@@ -1289,7 +1485,7 @@ static void DumpNode(CordRep* rep, bool include_data, std::ostream* os,
           *os << absl::CEscape(std::string(rep->flat()->Data(), rep->length));
         *os << "]\n";
       } else {
-        CordRepBtree::Dump(rep, /*label=*/ "", include_data, *os);
+        CordRepBtree::Dump(rep, /*label=*/"", include_data, *os);
       }
     }
     if (leaf) {
@@ -1303,16 +1499,17 @@ static void DumpNode(CordRep* rep, bool include_data, std::ostream* os,
   ABSL_INTERNAL_CHECK(indents.empty(), "");
 }
 
-static std::string ReportError(CordRep* root, CordRep* node) {
+static std::string ReportError(absl::Nonnull<CordRep*> root,
+                               absl::Nonnull<CordRep*> node) {
   std::ostringstream buf;
   buf << "Error at node " << node << " in:";
   DumpNode(root, true, &buf);
   return buf.str();
 }
 
-static bool VerifyNode(CordRep* root, CordRep* start_node,
-                       bool /* full_validation */) {
-  absl::InlinedVector<CordRep*, 2> worklist;
+static bool VerifyNode(absl::Nonnull<CordRep*> root,
+                       absl::Nonnull<CordRep*> start_node) {
+  absl::InlinedVector<absl::Nonnull<CordRep*>, 2> worklist;
   worklist.push_back(start_node);
   do {
     CordRep* node = worklist.back();
diff --git a/contrib/restricted/abseil-cpp/absl/strings/cord.h b/contrib/restricted/abseil-cpp/absl/strings/cord.h
index 457ccf0609..b3e556b6b4 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/cord.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/cord.h
@@ -74,6 +74,7 @@
 #include "absl/base/internal/endian.h"
 #include "absl/base/internal/per_thread_tls.h"
 #include "absl/base/macros.h"
+#include "absl/base/nullability.h"
 #include "absl/base/port.h"
 #include "absl/container/inlined_vector.h"
 #include "absl/crc/internal/crc_cord_state.h"
@@ -86,7 +87,6 @@
 #include "absl/strings/internal/cord_rep_btree.h"
 #include "absl/strings/internal/cord_rep_btree_reader.h"
 #include "absl/strings/internal/cord_rep_crc.h"
-#include "absl/strings/internal/cord_rep_ring.h"
 #include "absl/strings/internal/cordz_functions.h"
 #include "absl/strings/internal/cordz_info.h"
 #include "absl/strings/internal/cordz_statistics.h"
@@ -103,7 +103,7 @@ class Cord;
 class CordTestPeer;
 template <typename Releaser>
 Cord MakeCordFromExternal(absl::string_view, Releaser&&);
-void CopyCordToString(const Cord& src, std::string* dst);
+void CopyCordToString(const Cord& src, absl::Nonnull<std::string*> dst);
 
 // Cord memory accounting modes
 enum class CordMemoryAccounting {
@@ -120,8 +120,8 @@ enum class CordMemoryAccounting {
   //
   // For example:
   //   absl::Cord cord;
-  //   cord.append(some_other_cord);
-  //   cord.append(some_other_cord);
+  //   cord.Append(some_other_cord);
+  //   cord.Append(some_other_cord);
   //   // Counts `some_other_cord` twice:
   //   cord.EstimatedMemoryUsage(kTotal);
   //   // Counts `some_other_cord` once:
@@ -362,7 +362,7 @@ class Cord {
 
   // Cord::empty()
   //
-  // Determines whether the given Cord is empty, returning `true` is so.
+  // Determines whether the given Cord is empty, returning `true` if so.
   bool empty() const;
 
   // Cord::EstimatedMemoryUsage()
@@ -396,6 +396,12 @@ class Cord {
   bool EndsWith(absl::string_view rhs) const;
   bool EndsWith(const Cord& rhs) const;
 
+  // Cord::Contains()
+  //
+  // Determines whether the Cord contains the passed string data `rhs`.
+  bool Contains(absl::string_view rhs) const;
+  bool Contains(const Cord& rhs) const;
+
   // Cord::operator std::string()
   //
   // Converts a Cord into a `std::string()`. This operator is marked explicit to
@@ -411,7 +417,8 @@ class Cord {
   // guarantee that pointers previously returned by `dst->data()` remain valid
   // even if `*dst` had enough capacity to hold `src`. If `*dst` is a new
   // object, prefer to simply use the conversion operator to `std::string`.
-  friend void CopyCordToString(const Cord& src, std::string* dst);
+  friend void CopyCordToString(const Cord& src,
+                               absl::Nonnull<std::string*> dst);
 
   class CharIterator;
 
@@ -448,7 +455,7 @@ class Cord {
     using iterator_category = std::input_iterator_tag;
     using value_type = absl::string_view;
     using difference_type = ptrdiff_t;
-    using pointer = const value_type*;
+    using pointer = absl::Nonnull<const value_type*>;
     using reference = value_type;
 
     ChunkIterator() = default;
@@ -468,14 +475,14 @@ class Cord {
     using CordRepBtree = absl::cord_internal::CordRepBtree;
     using CordRepBtreeReader = absl::cord_internal::CordRepBtreeReader;
 
-    // Constructs a `begin()` iterator from `tree`. `tree` must not be null.
-    explicit ChunkIterator(cord_internal::CordRep* tree);
+    // Constructs a `begin()` iterator from `tree`.
+    explicit ChunkIterator(absl::Nonnull<cord_internal::CordRep*> tree);
 
     // Constructs a `begin()` iterator from `cord`.
-    explicit ChunkIterator(const Cord* cord);
+    explicit ChunkIterator(absl::Nonnull<const Cord*> cord);
 
     // Initializes this instance from a tree. Invoked by constructors.
-    void InitTree(cord_internal::CordRep* tree);
+    void InitTree(absl::Nonnull<cord_internal::CordRep*> tree);
 
     // Removes `n` bytes from `current_chunk_`. Expects `n` to be smaller than
     // `current_chunk_.size()`.
@@ -493,7 +500,7 @@ class Cord {
     // The current leaf, or `nullptr` if the iterator points to short data.
     // If the current chunk is a substring node, current_leaf_ points to the
     // underlying flat or external node.
-    absl::cord_internal::CordRep* current_leaf_ = nullptr;
+    absl::Nullable<absl::cord_internal::CordRep*> current_leaf_ = nullptr;
     // The number of bytes left in the `Cord` over which we are iterating.
     size_t bytes_remaining_ = 0;
 
@@ -515,7 +522,7 @@ class Cord {
   //                                         absl::string_view s) {
   //     return std::find(c.chunk_begin(), c.chunk_end(), s);
   //   }
-  ChunkIterator chunk_begin() const;
+  ChunkIterator chunk_begin() const ABSL_ATTRIBUTE_LIFETIME_BOUND;
 
   // Cord::chunk_end()
   //
@@ -524,7 +531,7 @@ class Cord {
   // Generally, prefer using `Cord::Chunks()` within a range-based for loop for
   // iterating over the chunks of a Cord. This method may be useful for getting
   // a `ChunkIterator` where range-based for-loops may not be available.
-  ChunkIterator chunk_end() const;
+  ChunkIterator chunk_end() const ABSL_ATTRIBUTE_LIFETIME_BOUND;
 
   //----------------------------------------------------------------------------
   // Cord::ChunkRange
@@ -550,13 +557,13 @@ class Cord {
     using iterator = ChunkIterator;
     using const_iterator = ChunkIterator;
 
-    explicit ChunkRange(const Cord* cord) : cord_(cord) {}
+    explicit ChunkRange(absl::Nonnull<const Cord*> cord) : cord_(cord) {}
 
     ChunkIterator begin() const;
     ChunkIterator end() const;
 
    private:
-    const Cord* cord_;
+    absl::Nonnull<const Cord*> cord_;
   };
 
   // Cord::Chunks()
@@ -578,7 +585,7 @@ class Cord {
   //       // The temporary Cord returned by CordFactory has been destroyed!
   //     }
   //   }
-  ChunkRange Chunks() const;
+  ChunkRange Chunks() const ABSL_ATTRIBUTE_LIFETIME_BOUND;
 
   //----------------------------------------------------------------------------
   // Cord::CharIterator
@@ -609,7 +616,7 @@ class Cord {
     using iterator_category = std::input_iterator_tag;
     using value_type = char;
     using difference_type = ptrdiff_t;
-    using pointer = const char*;
+    using pointer = absl::Nonnull<const char*>;
     using reference = const char&;
 
     CharIterator() = default;
@@ -624,7 +631,8 @@ class Cord {
     friend Cord;
 
    private:
-    explicit CharIterator(const Cord* cord) : chunk_iterator_(cord) {}
+    explicit CharIterator(absl::Nonnull<const Cord*> cord)
+        : chunk_iterator_(cord) {}
 
     ChunkIterator chunk_iterator_;
   };
@@ -635,14 +643,14 @@ class Cord {
   // advanced as a separate `Cord`. `n_bytes` must be less than or equal to the
   // number of bytes within the Cord; otherwise, behavior is undefined. It is
   // valid to pass `char_end()` and `0`.
-  static Cord AdvanceAndRead(CharIterator* it, size_t n_bytes);
+  static Cord AdvanceAndRead(absl::Nonnull<CharIterator*> it, size_t n_bytes);
 
   // Cord::Advance()
   //
   // Advances the `Cord::CharIterator` by `n_bytes`. `n_bytes` must be less than
   // or equal to the number of bytes remaining within the Cord; otherwise,
   // behavior is undefined. It is valid to pass `char_end()` and `0`.
-  static void Advance(CharIterator* it, size_t n_bytes);
+  static void Advance(absl::Nonnull<CharIterator*> it, size_t n_bytes);
 
   // Cord::ChunkRemaining()
   //
@@ -658,7 +666,7 @@ class Cord {
   // Generally, prefer using `Cord::Chars()` within a range-based for loop for
   // iterating over the chunks of a Cord. This method may be useful for getting
   // a `CharIterator` where range-based for-loops may not be available.
-  CharIterator char_begin() const;
+  CharIterator char_begin() const ABSL_ATTRIBUTE_LIFETIME_BOUND;
 
   // Cord::char_end()
   //
@@ -667,7 +675,7 @@ class Cord {
   // Generally, prefer using `Cord::Chars()` within a range-based for loop for
   // iterating over the chunks of a Cord. This method may be useful for getting
   // a `CharIterator` where range-based for-loops are not useful.
-  CharIterator char_end() const;
+  CharIterator char_end() const ABSL_ATTRIBUTE_LIFETIME_BOUND;
 
   // Cord::CharRange
   //
@@ -691,13 +699,13 @@ class Cord {
     using iterator = CharIterator;
     using const_iterator = CharIterator;
 
-    explicit CharRange(const Cord* cord) : cord_(cord) {}
+    explicit CharRange(absl::Nonnull<const Cord*> cord) : cord_(cord) {}
 
     CharIterator begin() const;
     CharIterator end() const;
 
    private:
-    const Cord* cord_;
+    absl::Nonnull<const Cord*> cord_;
   };
 
   // Cord::Chars()
@@ -719,7 +727,7 @@ class Cord {
   //       // The temporary Cord returned by CordFactory has been destroyed!
   //     }
   //   }
-  CharRange Chars() const;
+  CharRange Chars() const ABSL_ATTRIBUTE_LIFETIME_BOUND;
 
   // Cord::operator[]
   //
@@ -737,20 +745,38 @@ class Cord {
   //
   // If this cord's representation is a single flat array, returns a
   // string_view referencing that array.  Otherwise returns nullopt.
-  absl::optional<absl::string_view> TryFlat() const;
+  absl::optional<absl::string_view> TryFlat() const
+      ABSL_ATTRIBUTE_LIFETIME_BOUND;
 
   // Cord::Flatten()
   //
   // Flattens the cord into a single array and returns a view of the data.
   //
   // If the cord was already flat, the contents are not modified.
-  absl::string_view Flatten();
+  absl::string_view Flatten() ABSL_ATTRIBUTE_LIFETIME_BOUND;
+
+  // Cord::Find()
+  //
+  // Returns an iterator to the first occurrance of the substring `needle`.
+  //
+  // If the substring `needle` does not occur, `Cord::char_end()` is returned.
+  CharIterator Find(absl::string_view needle) const;
+  CharIterator Find(const absl::Cord& needle) const;
 
   // Supports absl::Cord as a sink object for absl::Format().
-  friend void AbslFormatFlush(absl::Cord* cord, absl::string_view part) {
+  friend void AbslFormatFlush(absl::Nonnull<absl::Cord*> cord,
+                              absl::string_view part) {
     cord->Append(part);
   }
 
+  // Support automatic stringification with absl::StrCat and absl::StrFormat.
+  template <typename Sink>
+  friend void AbslStringify(Sink& sink, const absl::Cord& cord) {
+    for (absl::string_view chunk : cord.Chunks()) {
+      sink.Append(chunk);
+    }
+  }
+
   // Cord::SetExpectedChecksum()
   //
   // Stores a checksum value with this non-empty cord instance, for later
@@ -809,7 +835,8 @@ class Cord {
   friend bool operator==(const Cord& lhs, const Cord& rhs);
   friend bool operator==(const Cord& lhs, absl::string_view rhs);
 
-  friend const CordzInfo* GetCordzInfoForTesting(const Cord& cord);
+  friend absl::Nullable<const CordzInfo*> GetCordzInfoForTesting(
+      const Cord& cord);
 
   // Calls the provided function once for each cord chunk, in order.  Unlike
   // Chunks(), this API will not allocate memory.
@@ -836,20 +863,22 @@ class Cord {
     InlineRep& operator=(const InlineRep& src);
     InlineRep& operator=(InlineRep&& src) noexcept;
 
-    explicit constexpr InlineRep(absl::string_view sv, CordRep* rep);
+    explicit constexpr InlineRep(absl::string_view sv,
+                                 absl::Nullable<CordRep*> rep);
 
-    void Swap(InlineRep* rhs);
-    bool empty() const;
+    void Swap(absl::Nonnull<InlineRep*> rhs);
     size_t size() const;
-    const char* data() const;  // Returns nullptr if holding pointer
-    void set_data(const char* data, size_t n);  // Discards pointer, if any
-    char* set_data(size_t n);                   // Write data to the result
+    // Returns nullptr if holding pointer
+    absl::Nullable<const char*> data() const;
+    // Discards pointer, if any
+    void set_data(absl::Nonnull<const char*> data, size_t n);
+    absl::Nonnull<char*> set_data(size_t n);  // Write data to the result
     // Returns nullptr if holding bytes
-    absl::cord_internal::CordRep* tree() const;
-    absl::cord_internal::CordRep* as_tree() const;
-    const char* as_chars() const;
+    absl::Nullable<absl::cord_internal::CordRep*> tree() const;
+    absl::Nonnull<absl::cord_internal::CordRep*> as_tree() const;
+    absl::Nonnull<const char*> as_chars() const;
     // Returns non-null iff was holding a pointer
-    absl::cord_internal::CordRep* clear();
+    absl::Nullable<absl::cord_internal::CordRep*> clear();
     // Converts to pointer if necessary.
     void reduce_size(size_t n);    // REQUIRES: holding data
     void remove_prefix(size_t n);  // REQUIRES: holding data
@@ -858,46 +887,52 @@ class Cord {
 
     // Creates a CordRepFlat instance from the current inlined data with `extra'
     // bytes of desired additional capacity.
-    CordRepFlat* MakeFlatWithExtraCapacity(size_t extra);
+    absl::Nonnull<CordRepFlat*> MakeFlatWithExtraCapacity(size_t extra);
 
     // Sets the tree value for this instance. `rep` must not be null.
     // Requires the current instance to hold a tree, and a lock to be held on
     // any CordzInfo referenced by this instance. The latter is enforced through
     // the CordzUpdateScope argument. If the current instance is sampled, then
     // the CordzInfo instance is updated to reference the new `rep` value.
-    void SetTree(CordRep* rep, const CordzUpdateScope& scope);
+    void SetTree(absl::Nonnull<CordRep*> rep, const CordzUpdateScope& scope);
 
     // Identical to SetTree(), except that `rep` is allowed to be null, in
     // which case the current instance is reset to an empty value.
-    void SetTreeOrEmpty(CordRep* rep, const CordzUpdateScope& scope);
+    void SetTreeOrEmpty(absl::Nullable<CordRep*> rep,
+                        const CordzUpdateScope& scope);
 
     // Sets the tree value for this instance, and randomly samples this cord.
     // This function disregards existing contents in `data_`, and should be
     // called when a Cord is 'promoted' from an 'uninitialized' or 'inlined'
     // value to a non-inlined (tree / ring) value.
-    void EmplaceTree(CordRep* rep, MethodIdentifier method);
+    void EmplaceTree(absl::Nonnull<CordRep*> rep, MethodIdentifier method);
 
     // Identical to EmplaceTree, except that it copies the parent stack from
     // the provided `parent` data if the parent is sampled.
-    void EmplaceTree(CordRep* rep, const InlineData& parent,
+    void EmplaceTree(absl::Nonnull<CordRep*> rep, const InlineData& parent,
                      MethodIdentifier method);
 
     // Commits the change of a newly created, or updated `rep` root value into
     // this cord. `old_rep` indicates the old (inlined or tree) value of the
     // cord, and determines if the commit invokes SetTree() or EmplaceTree().
-    void CommitTree(const CordRep* old_rep, CordRep* rep,
-                    const CordzUpdateScope& scope, MethodIdentifier method);
-
-    void AppendTreeToInlined(CordRep* tree, MethodIdentifier method);
-    void AppendTreeToTree(CordRep* tree, MethodIdentifier method);
-    void AppendTree(CordRep* tree, MethodIdentifier method);
-    void PrependTreeToInlined(CordRep* tree, MethodIdentifier method);
-    void PrependTreeToTree(CordRep* tree, MethodIdentifier method);
-    void PrependTree(CordRep* tree, MethodIdentifier method);
+    void CommitTree(absl::Nullable<const CordRep*> old_rep,
+                    absl::Nonnull<CordRep*> rep, const CordzUpdateScope& scope,
+                    MethodIdentifier method);
+
+    void AppendTreeToInlined(absl::Nonnull<CordRep*> tree,
+                             MethodIdentifier method);
+    void AppendTreeToTree(absl::Nonnull<CordRep*> tree,
+                          MethodIdentifier method);
+    void AppendTree(absl::Nonnull<CordRep*> tree, MethodIdentifier method);
+    void PrependTreeToInlined(absl::Nonnull<CordRep*> tree,
+                              MethodIdentifier method);
+    void PrependTreeToTree(absl::Nonnull<CordRep*> tree,
+                           MethodIdentifier method);
+    void PrependTree(absl::Nonnull<CordRep*> tree, MethodIdentifier method);
 
     bool IsSame(const InlineRep& other) const { return data_ == other.data_; }
 
-    void CopyTo(std::string* dst) const {
+    void CopyTo(absl::Nonnull<std::string*> dst) const {
       // memcpy is much faster when operating on a known size. On most supported
       // platforms, the small string optimization is large enough that resizing
       // to 15 bytes does not cause a memory allocation.
@@ -909,7 +944,7 @@ class Cord {
     }
 
     // Copies the inline contents into `dst`. Assumes the cord is not empty.
-    void CopyToArray(char* dst) const;
+    void CopyToArray(absl::Nonnull<char*> dst) const;
 
     bool is_tree() const { return data_.is_tree(); }
 
@@ -922,12 +957,12 @@ class Cord {
     }
 
     // Returns the profiled CordzInfo, or nullptr if not sampled.
-    absl::cord_internal::CordzInfo* cordz_info() const {
+    absl::Nullable<absl::cord_internal::CordzInfo*> cordz_info() const {
       return data_.cordz_info();
     }
 
-    // Sets the profiled CordzInfo. `cordz_info` must not be null.
-    void set_cordz_info(cord_internal::CordzInfo* cordz_info) {
+    // Sets the profiled CordzInfo.
+    void set_cordz_info(absl::Nonnull<cord_internal::CordzInfo*> cordz_info) {
       assert(cordz_info != nullptr);
       data_.set_cordz_info(cordz_info);
     }
@@ -959,19 +994,19 @@ class Cord {
   InlineRep contents_;
 
   // Helper for GetFlat() and TryFlat().
-  static bool GetFlatAux(absl::cord_internal::CordRep* rep,
-                         absl::string_view* fragment);
+  static bool GetFlatAux(absl::Nonnull<absl::cord_internal::CordRep*> rep,
+                         absl::Nonnull<absl::string_view*> fragment);
 
   // Helper for ForEachChunk().
   static void ForEachChunkAux(
-      absl::cord_internal::CordRep* rep,
+      absl::Nonnull<absl::cord_internal::CordRep*> rep,
       absl::FunctionRef<void(absl::string_view)> callback);
 
   // The destructor for non-empty Cords.
   void DestroyCordSlow();
 
   // Out-of-line implementation of slower parts of logic.
-  void CopyToArraySlowPath(char* dst) const;
+  void CopyToArraySlowPath(absl::Nonnull<char*> dst) const;
   int CompareSlowPath(absl::string_view rhs, size_t compared_size,
                       size_t size_to_compare) const;
   int CompareSlowPath(const Cord& rhs, size_t compared_size,
@@ -988,8 +1023,8 @@ class Cord {
 
   // Returns a new reference to contents_.tree(), or steals an existing
   // reference if called on an rvalue.
-  absl::cord_internal::CordRep* TakeRep() const&;
-  absl::cord_internal::CordRep* TakeRep() &&;
+  absl::Nonnull<absl::cord_internal::CordRep*> TakeRep() const&;
+  absl::Nonnull<absl::cord_internal::CordRep*> TakeRep() &&;
 
   // Helper for Append().
   template <typename C>
@@ -1026,7 +1061,10 @@ class Cord {
 
   friend class CrcCord;
   void SetCrcCordState(crc_internal::CrcCordState state);
-  const crc_internal::CrcCordState* MaybeGetCrcCordState() const;
+  absl::Nullable<const crc_internal::CrcCordState*> MaybeGetCrcCordState()
+      const;
+
+  CharIterator FindImpl(CharIterator it, absl::string_view needle) const;
 };
 
 ABSL_NAMESPACE_END
@@ -1045,13 +1083,15 @@ namespace cord_internal {
 
 // Does non-template-specific `CordRepExternal` initialization.
 // Requires `data` to be non-empty.
-void InitializeCordRepExternal(absl::string_view data, CordRepExternal* rep);
+void InitializeCordRepExternal(absl::string_view data,
+                               absl::Nonnull<CordRepExternal*> rep);
 
 // Creates a new `CordRep` that owns `data` and `releaser` and returns a pointer
 // to it. Requires `data` to be non-empty.
 template <typename Releaser>
 // NOLINTNEXTLINE - suppress clang-tidy raw pointer return.
-CordRep* NewExternalRep(absl::string_view data, Releaser&& releaser) {
+absl::Nonnull<CordRep*> NewExternalRep(absl::string_view data,
+                                       Releaser&& releaser) {
   assert(!data.empty());
   using ReleaserType = absl::decay_t<Releaser>;
   CordRepExternal* rep = new CordRepExternalImpl<ReleaserType>(
@@ -1063,7 +1103,7 @@ CordRep* NewExternalRep(absl::string_view data, Releaser&& releaser) {
 // Overload for function reference types that dispatches using a function
 // pointer because there are no `alignof()` or `sizeof()` a function reference.
 // NOLINTNEXTLINE - suppress clang-tidy raw pointer return.
-inline CordRep* NewExternalRep(absl::string_view data,
+inline absl::Nonnull<CordRep*> NewExternalRep(absl::string_view data,
                                void (&releaser)(absl::string_view)) {
   return NewExternalRep(data, &releaser);
 }
@@ -1086,7 +1126,8 @@ Cord MakeCordFromExternal(absl::string_view data, Releaser&& releaser) {
   return cord;
 }
 
-constexpr Cord::InlineRep::InlineRep(absl::string_view sv, CordRep* rep)
+constexpr Cord::InlineRep::InlineRep(absl::string_view sv,
+                                     absl::Nullable<CordRep*> rep)
     : data_(sv, rep) {}
 
 inline Cord::InlineRep::InlineRep(const Cord::InlineRep& src)
@@ -1125,28 +1166,30 @@ inline Cord::InlineRep& Cord::InlineRep::operator=(
   return *this;
 }
 
-inline void Cord::InlineRep::Swap(Cord::InlineRep* rhs) {
+inline void Cord::InlineRep::Swap(absl::Nonnull<Cord::InlineRep*> rhs) {
   if (rhs == this) {
     return;
   }
   std::swap(data_, rhs->data_);
 }
 
-inline const char* Cord::InlineRep::data() const {
+inline absl::Nullable<const char*> Cord::InlineRep::data() const {
   return is_tree() ? nullptr : data_.as_chars();
 }
 
-inline const char* Cord::InlineRep::as_chars() const {
+inline absl::Nonnull<const char*> Cord::InlineRep::as_chars() const {
   assert(!data_.is_tree());
   return data_.as_chars();
 }
 
-inline absl::cord_internal::CordRep* Cord::InlineRep::as_tree() const {
+inline absl::Nonnull<absl::cord_internal::CordRep*> Cord::InlineRep::as_tree()
+    const {
   assert(data_.is_tree());
   return data_.as_tree();
 }
 
-inline absl::cord_internal::CordRep* Cord::InlineRep::tree() const {
+inline absl::Nullable<absl::cord_internal::CordRep*> Cord::InlineRep::tree()
+    const {
   if (is_tree()) {
     return as_tree();
   } else {
@@ -1154,14 +1197,12 @@ inline absl::cord_internal::CordRep* Cord::InlineRep::tree() const {
   }
 }
 
-inline bool Cord::InlineRep::empty() const { return data_.is_empty(); }
-
 inline size_t Cord::InlineRep::size() const {
   return is_tree() ? as_tree()->length : inline_size();
 }
 
-inline cord_internal::CordRepFlat* Cord::InlineRep::MakeFlatWithExtraCapacity(
-    size_t extra) {
+inline absl::Nonnull<cord_internal::CordRepFlat*>
+Cord::InlineRep::MakeFlatWithExtraCapacity(size_t extra) {
   static_assert(cord_internal::kMinFlatLength >= sizeof(data_), "");
   size_t len = data_.inline_size();
   auto* result = CordRepFlat::New(len + extra);
@@ -1170,20 +1211,21 @@ inline cord_internal::CordRepFlat* Cord::InlineRep::MakeFlatWithExtraCapacity(
   return result;
 }
 
-inline void Cord::InlineRep::EmplaceTree(CordRep* rep,
+inline void Cord::InlineRep::EmplaceTree(absl::Nonnull<CordRep*> rep,
                                          MethodIdentifier method) {
   assert(rep);
   data_.make_tree(rep);
   CordzInfo::MaybeTrackCord(data_, method);
 }
 
-inline void Cord::InlineRep::EmplaceTree(CordRep* rep, const InlineData& parent,
+inline void Cord::InlineRep::EmplaceTree(absl::Nonnull<CordRep*> rep,
+                                         const InlineData& parent,
                                          MethodIdentifier method) {
   data_.make_tree(rep);
   CordzInfo::MaybeTrackCord(data_, parent, method);
 }
 
-inline void Cord::InlineRep::SetTree(CordRep* rep,
+inline void Cord::InlineRep::SetTree(absl::Nonnull<CordRep*> rep,
                                      const CordzUpdateScope& scope) {
   assert(rep);
   assert(data_.is_tree());
@@ -1191,7 +1233,7 @@ inline void Cord::InlineRep::SetTree(CordRep* rep,
   scope.SetCordRep(rep);
 }
 
-inline void Cord::InlineRep::SetTreeOrEmpty(CordRep* rep,
+inline void Cord::InlineRep::SetTreeOrEmpty(absl::Nullable<CordRep*> rep,
                                             const CordzUpdateScope& scope) {
   assert(data_.is_tree());
   if (rep) {
@@ -1202,7 +1244,8 @@ inline void Cord::InlineRep::SetTreeOrEmpty(CordRep* rep,
   scope.SetCordRep(rep);
 }
 
-inline void Cord::InlineRep::CommitTree(const CordRep* old_rep, CordRep* rep,
+inline void Cord::InlineRep::CommitTree(absl::Nullable<const CordRep*> old_rep,
+                                        absl::Nonnull<CordRep*> rep,
                                         const CordzUpdateScope& scope,
                                         MethodIdentifier method) {
   if (old_rep) {
@@ -1212,7 +1255,7 @@ inline void Cord::InlineRep::CommitTree(const CordRep* old_rep, CordRep* rep,
   }
 }
 
-inline absl::cord_internal::CordRep* Cord::InlineRep::clear() {
+inline absl::Nullable<absl::cord_internal::CordRep*> Cord::InlineRep::clear() {
   if (is_tree()) {
     CordzInfo::MaybeUntrackCord(cordz_info());
   }
@@ -1221,7 +1264,7 @@ inline absl::cord_internal::CordRep* Cord::InlineRep::clear() {
   return result;
 }
 
-inline void Cord::InlineRep::CopyToArray(char* dst) const {
+inline void Cord::InlineRep::CopyToArray(absl::Nonnull<char*> dst) const {
   assert(!is_tree());
   size_t n = inline_size();
   assert(n != 0);
@@ -1402,7 +1445,8 @@ inline bool Cord::StartsWith(absl::string_view rhs) const {
   return EqualsImpl(rhs, rhs_size);
 }
 
-inline void Cord::ChunkIterator::InitTree(cord_internal::CordRep* tree) {
+inline void Cord::ChunkIterator::InitTree(
+    absl::Nonnull<cord_internal::CordRep*> tree) {
   tree = cord_internal::SkipCrcNode(tree);
   if (tree->tag == cord_internal::BTREE) {
     current_chunk_ = btree_reader_.Init(tree->btree());
@@ -1412,12 +1456,13 @@ inline void Cord::ChunkIterator::InitTree(cord_internal::CordRep* tree) {
   }
 }
 
-inline Cord::ChunkIterator::ChunkIterator(cord_internal::CordRep* tree) {
+inline Cord::ChunkIterator::ChunkIterator(
+    absl::Nonnull<cord_internal::CordRep*> tree) {
   bytes_remaining_ = tree->length;
   InitTree(tree);
 }
 
-inline Cord::ChunkIterator::ChunkIterator(const Cord* cord) {
+inline Cord::ChunkIterator::ChunkIterator(absl::Nonnull<const Cord*> cord) {
   if (CordRep* tree = cord->contents_.tree()) {
     bytes_remaining_ = tree->length;
     if (ABSL_PREDICT_TRUE(bytes_remaining_ != 0)) {
@@ -1557,12 +1602,13 @@ inline Cord::CharIterator::pointer Cord::CharIterator::operator->() const {
   return chunk_iterator_->data();
 }
 
-inline Cord Cord::AdvanceAndRead(CharIterator* it, size_t n_bytes) {
+inline Cord Cord::AdvanceAndRead(absl::Nonnull<CharIterator*> it,
+                                 size_t n_bytes) {
   assert(it != nullptr);
   return it->chunk_iterator_.AdvanceAndReadBytes(n_bytes);
 }
 
-inline void Cord::Advance(CharIterator* it, size_t n_bytes) {
+inline void Cord::Advance(absl::Nonnull<CharIterator*> it, size_t n_bytes) {
   assert(it != nullptr);
   it->chunk_iterator_.AdvanceBytes(n_bytes);
 }
@@ -1618,7 +1664,7 @@ inline bool operator>=(const Cord& x, const Cord& y) {
 // Nonmember Cord-to-absl::string_view relational operators.
 //
 // Due to implicit conversions, these also enable comparisons of Cord with
-// with std::string, ::string, and const char*.
+// std::string and const char*.
 inline bool operator==(const Cord& lhs, absl::string_view rhs) {
   size_t lhs_size = lhs.size();
   size_t rhs_size = rhs.size();
diff --git a/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.cc b/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.cc
index e859b0db06..19b0fa4436 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.cc
@@ -14,23 +14,17 @@
 
 #include "absl/strings/cord_analysis.h"
 
+#include <cassert>
 #include <cstddef>
 #include <cstdint>
 #include <unordered_set>
 
-#include "absl/base/attributes.h"
 #include "absl/base/config.h"
-#include "absl/container/inlined_vector.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/internal/cord_data_edge.h"
 #include "absl/strings/internal/cord_internal.h"
 #include "absl/strings/internal/cord_rep_btree.h"
 #include "absl/strings/internal/cord_rep_crc.h"
-#include "absl/strings/internal/cord_rep_flat.h"
-#include "absl/strings/internal/cord_rep_ring.h"
-//
-#include "absl/base/macros.h"
-#include "absl/base/port.h"
-#include "absl/functional/function_ref.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -45,13 +39,15 @@ enum class Mode { kFairShare, kTotal, kTotalMorePrecise };
 template <Mode mode>
 struct CordRepRef {
   // Instantiates a CordRepRef instance.
-  explicit CordRepRef(const CordRep* r) : rep(r) {}
+  explicit CordRepRef(absl::Nonnull<const CordRep*> r) : rep(r) {}
 
   // Creates a child reference holding the provided child.
   // Overloaded to add cumulative reference count for kFairShare.
-  CordRepRef Child(const CordRep* child) const { return CordRepRef(child); }
+  CordRepRef Child(absl::Nonnull<const CordRep*> child) const {
+    return CordRepRef(child);
+  }
 
-  const CordRep* rep;
+  absl::Nonnull<const CordRep*> rep;
 };
 
 // RawUsage holds the computed total number of bytes.
@@ -70,11 +66,10 @@ template <>
 struct RawUsage<Mode::kTotalMorePrecise> {
   size_t total = 0;
   // TODO(b/289250880): Replace this with a flat_hash_set.
-  std::unordered_set<const CordRep*> counted;
+  std::unordered_set<absl::Nonnull<const CordRep*>> counted;
 
   void Add(size_t size, CordRepRef<Mode::kTotalMorePrecise> repref) {
-    if (counted.find(repref.rep) == counted.end()) {
-      counted.insert(repref.rep);
+    if (counted.insert(repref.rep).second) {
       total += size;
     }
   }
@@ -95,15 +90,15 @@ double MaybeDiv(double d, refcount_t refcount) {
 template <>
 struct CordRepRef<Mode::kFairShare> {
   // Creates a CordRepRef with the provided rep and top (parent) fraction.
-  explicit CordRepRef(const CordRep* r, double frac = 1.0)
+  explicit CordRepRef(absl::Nonnull<const CordRep*> r, double frac = 1.0)
       : rep(r), fraction(MaybeDiv(frac, r->refcount.Get())) {}
 
   // Returns a CordRepRef with a fraction of `this->fraction / child.refcount`
-  CordRepRef Child(const CordRep* child) const {
+  CordRepRef Child(absl::Nonnull<const CordRep*> child) const {
     return CordRepRef(child, fraction);
   }
 
-  const CordRep* rep;
+  absl::Nonnull<const CordRep*> rep;
   double fraction;
 };
 
@@ -138,16 +133,6 @@ void AnalyzeDataEdge(CordRepRef<mode> rep, RawUsage<mode>& raw_usage) {
   raw_usage.Add(size, rep);
 }
 
-// Computes the memory size of the provided Ring tree.
-template <Mode mode>
-void AnalyzeRing(CordRepRef<mode> rep, RawUsage<mode>& raw_usage) {
-  const CordRepRing* ring = rep.rep->ring();
-  raw_usage.Add(CordRepRing::AllocSize(ring->capacity()), rep);
-  ring->ForEach([&](CordRepRing::index_type pos) {
-    AnalyzeDataEdge(rep.Child(ring->entry_child(pos)), raw_usage);
-  });
-}
-
 // Computes the memory size of the provided Btree tree.
 template <Mode mode>
 void AnalyzeBtree(CordRepRef<mode> rep, RawUsage<mode>& raw_usage) {
@@ -165,7 +150,7 @@ void AnalyzeBtree(CordRepRef<mode> rep, RawUsage<mode>& raw_usage) {
 }
 
 template <Mode mode>
-size_t GetEstimatedUsage(const CordRep* rep) {
+size_t GetEstimatedUsage(absl::Nonnull<const CordRep*> rep) {
   // Zero initialized memory usage totals.
   RawUsage<mode> raw_usage;
 
@@ -175,6 +160,9 @@ size_t GetEstimatedUsage(const CordRep* rep) {
   // Consume the top level CRC node if present.
   if (repref.rep->tag == CRC) {
     raw_usage.Add(sizeof(CordRepCrc), repref);
+    if (repref.rep->crc()->child == nullptr) {
+      return static_cast<size_t>(raw_usage.total);
+    }
     repref = repref.Child(repref.rep->crc()->child);
   }
 
@@ -182,8 +170,6 @@ size_t GetEstimatedUsage(const CordRep* rep) {
     AnalyzeDataEdge(repref, raw_usage);
   } else if (repref.rep->tag == BTREE) {
     AnalyzeBtree(repref, raw_usage);
-  } else if (repref.rep->tag == RING) {
-    AnalyzeRing(repref, raw_usage);
   } else {
     assert(false);
   }
@@ -193,15 +179,15 @@ size_t GetEstimatedUsage(const CordRep* rep) {
 
 }  // namespace
 
-size_t GetEstimatedMemoryUsage(const CordRep* rep) {
+size_t GetEstimatedMemoryUsage(absl::Nonnull<const CordRep*> rep) {
   return GetEstimatedUsage<Mode::kTotal>(rep);
 }
 
-size_t GetEstimatedFairShareMemoryUsage(const CordRep* rep) {
+size_t GetEstimatedFairShareMemoryUsage(absl::Nonnull<const CordRep*> rep) {
   return GetEstimatedUsage<Mode::kFairShare>(rep);
 }
 
-size_t GetMorePreciseMemoryUsage(const CordRep* rep) {
+size_t GetMorePreciseMemoryUsage(absl::Nonnull<const CordRep*> rep) {
   return GetEstimatedUsage<Mode::kTotalMorePrecise>(rep);
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.h b/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.h
index 9b9527a57d..f8ce348984 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/cord_analysis.h
@@ -19,6 +19,7 @@
 #include <cstdint>
 
 #include "absl/base/config.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/internal/cord_internal.h"
 
 namespace absl {
@@ -28,7 +29,7 @@ namespace cord_internal {
 // Returns the *approximate* number of bytes held in full or in part by this
 // Cord (which may not remain the same between invocations). Cords that share
 // memory could each be "charged" independently for the same shared memory.
-size_t GetEstimatedMemoryUsage(const CordRep* rep);
+size_t GetEstimatedMemoryUsage(absl::Nonnull<const CordRep*> rep);
 
 // Returns the *approximate* number of bytes held in full or in part by this
 // Cord for the distinct memory held by this cord. This is similar to
@@ -46,13 +47,13 @@ size_t GetEstimatedMemoryUsage(const CordRep* rep);
 //
 // This is more expensive than `GetEstimatedMemoryUsage()` as it requires
 // deduplicating all memory references.
-size_t GetMorePreciseMemoryUsage(const CordRep* rep);
+size_t GetMorePreciseMemoryUsage(absl::Nonnull<const CordRep*> rep);
 
 // Returns the *approximate* number of bytes held in full or in part by this
 // CordRep weighted by the sharing ratio of that data. For example, if some data
 // edge is shared by 4 different Cords, then each cord is attribute 1/4th of
 // the total memory usage as a 'fair share' of the total memory usage.
-size_t GetEstimatedFairShareMemoryUsage(const CordRep* rep);
+size_t GetEstimatedFairShareMemoryUsage(absl::Nonnull<const CordRep*> rep);
 
 }  // namespace cord_internal
 ABSL_NAMESPACE_END
diff --git a/contrib/restricted/abseil-cpp/absl/strings/escaping.cc b/contrib/restricted/abseil-cpp/absl/strings/escaping.cc
index 2827fbaa37..1c0eac42d7 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/escaping.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/escaping.cc
@@ -16,21 +16,22 @@
 
 #include <algorithm>
 #include <cassert>
+#include <cstddef>
 #include <cstdint>
 #include <cstring>
-#include <iterator>
 #include <limits>
 #include <string>
 
-#include "absl/base/internal/endian.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/base/internal/unaligned_access.h"
-#include "absl/strings/internal/char_map.h"
+#include "absl/strings/ascii.h"
+#include "absl/strings/charset.h"
 #include "absl/strings/internal/escaping.h"
 #include "absl/strings/internal/resize_uninitialized.h"
 #include "absl/strings/internal/utf8.h"
+#include "absl/strings/numbers.h"
 #include "absl/strings/str_cat.h"
-#include "absl/strings/str_join.h"
 #include "absl/strings/string_view.h"
 
 namespace absl {
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/has_absl_stringify.h b/contrib/restricted/abseil-cpp/absl/strings/has_absl_stringify.h
index 55a0850829..274a7865d1 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/has_absl_stringify.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/has_absl_stringify.h
@@ -12,9 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#ifndef ABSL_STRINGS_INTERNAL_HAS_ABSL_STRINGIFY_H_
-#define ABSL_STRINGS_INTERNAL_HAS_ABSL_STRINGIFY_H_
-#include <string>
+#ifndef ABSL_STRINGS_HAS_ABSL_STRINGIFY_H_
+#define ABSL_STRINGS_HAS_ABSL_STRINGIFY_H_
+
 #include <type_traits>
 #include <utility>
 
@@ -38,6 +38,16 @@ class UnimplementedSink {
   friend void AbslFormatFlush(UnimplementedSink* sink, absl::string_view v);
 };
 
+}  // namespace strings_internal
+
+// `HasAbslStringify<T>` detects if type `T` supports the `AbslStringify()`
+// customization point (see
+// https://abseil.io/docs/cpp/guides/format#abslstringify for the
+// documentation).
+//
+// Note that there are types that can be `StrCat`-ed that do not use the
+// `AbslStringify` customization point (for example, `int`).
+
 template <typename T, typename = void>
 struct HasAbslStringify : std::false_type {};
 
@@ -47,9 +57,7 @@ struct HasAbslStringify<
            std::declval<strings_internal::UnimplementedSink&>(),
            std::declval<const T&>()))>::value>> : std::true_type {};
 
-}  // namespace strings_internal
-
 ABSL_NAMESPACE_END
 }  // namespace absl
 
-#endif  // ABSL_STRINGS_INTERNAL_HAS_ABSL_STRINGIFY_H_
+#endif  // ABSL_STRINGS_HAS_ABSL_STRINGIFY_H_
diff --git a/contrib/restricted/abseil-cpp/absl/strings/has_ostream_operator.h b/contrib/restricted/abseil-cpp/absl/strings/has_ostream_operator.h
new file mode 100644
index 0000000000..156ffc743d
--- /dev/null
+++ b/contrib/restricted/abseil-cpp/absl/strings/has_ostream_operator.h
@@ -0,0 +1,42 @@
+// Copyright 2023 The Abseil Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef ABSL_STRINGS_HAS_OSTREAM_OPERATOR_H_
+#define ABSL_STRINGS_HAS_OSTREAM_OPERATOR_H_
+
+#include <ostream>
+#include <type_traits>
+#include <utility>
+
+#include "absl/base/config.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+
+// Detects if type `T` supports streaming to `std::ostream`s with `operator<<`.
+
+template <typename T, typename = void>
+struct HasOstreamOperator : std::false_type {};
+
+template <typename T>
+struct HasOstreamOperator<
+    T, std::enable_if_t<std::is_same<
+           std::ostream&, decltype(std::declval<std::ostream&>()
+                                   << std::declval<const T&>())>::value>>
+    : std::true_type {};
+
+ABSL_NAMESPACE_END
+}  // namespace absl
+
+#endif  // ABSL_STRINGS_HAS_OSTREAM_OPERATOR_H_
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/char_map.h b/contrib/restricted/abseil-cpp/absl/strings/internal/char_map.h
deleted file mode 100644
index 70a9034336..0000000000
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/char_map.h
+++ /dev/null
@@ -1,158 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-// Character Map Class
-//
-// A fast, bit-vector map for 8-bit unsigned characters.
-// This class is useful for non-character purposes as well.
-
-#ifndef ABSL_STRINGS_INTERNAL_CHAR_MAP_H_
-#define ABSL_STRINGS_INTERNAL_CHAR_MAP_H_
-
-#include <cstddef>
-#include <cstdint>
-#include <cstring>
-
-#include "absl/base/macros.h"
-#include "absl/base/port.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace strings_internal {
-
-class Charmap {
- public:
-  constexpr Charmap() : m_() {}
-
-  // Initializes with a given char*.  Note that NUL is not treated as
-  // a terminator, but rather a char to be flicked.
-  Charmap(const char* str, int len) : m_() {
-    while (len--) SetChar(*str++);
-  }
-
-  // Initializes with a given char*.  NUL is treated as a terminator
-  // and will not be in the charmap.
-  explicit Charmap(const char* str) : m_() {
-    while (*str) SetChar(*str++);
-  }
-
-  constexpr bool contains(unsigned char c) const {
-    return (m_[c / 64] >> (c % 64)) & 0x1;
-  }
-
-  // Returns true if and only if a character exists in both maps.
-  bool IntersectsWith(const Charmap& c) const {
-    for (size_t i = 0; i < ABSL_ARRAYSIZE(m_); ++i) {
-      if ((m_[i] & c.m_[i]) != 0) return true;
-    }
-    return false;
-  }
-
-  bool IsZero() const {
-    for (uint64_t c : m_) {
-      if (c != 0) return false;
-    }
-    return true;
-  }
-
-  // Containing only a single specified char.
-  static constexpr Charmap Char(char x) {
-    return Charmap(CharMaskForWord(x, 0), CharMaskForWord(x, 1),
-                   CharMaskForWord(x, 2), CharMaskForWord(x, 3));
-  }
-
-  // Containing all the chars in the C-string 's'.
-  static constexpr Charmap FromString(const char* s) {
-    Charmap ret;
-    while (*s) ret = ret | Char(*s++);
-    return ret;
-  }
-
-  // Containing all the chars in the closed interval [lo,hi].
-  static constexpr Charmap Range(char lo, char hi) {
-    return Charmap(RangeForWord(lo, hi, 0), RangeForWord(lo, hi, 1),
-                   RangeForWord(lo, hi, 2), RangeForWord(lo, hi, 3));
-  }
-
-  friend constexpr Charmap operator&(const Charmap& a, const Charmap& b) {
-    return Charmap(a.m_[0] & b.m_[0], a.m_[1] & b.m_[1], a.m_[2] & b.m_[2],
-                   a.m_[3] & b.m_[3]);
-  }
-
-  friend constexpr Charmap operator|(const Charmap& a, const Charmap& b) {
-    return Charmap(a.m_[0] | b.m_[0], a.m_[1] | b.m_[1], a.m_[2] | b.m_[2],
-                   a.m_[3] | b.m_[3]);
-  }
-
-  friend constexpr Charmap operator~(const Charmap& a) {
-    return Charmap(~a.m_[0], ~a.m_[1], ~a.m_[2], ~a.m_[3]);
-  }
-
- private:
-  constexpr Charmap(uint64_t b0, uint64_t b1, uint64_t b2, uint64_t b3)
-      : m_{b0, b1, b2, b3} {}
-
-  static constexpr uint64_t RangeForWord(char lo, char hi, uint64_t word) {
-    return OpenRangeFromZeroForWord(static_cast<unsigned char>(hi) + 1, word) &
-           ~OpenRangeFromZeroForWord(static_cast<unsigned char>(lo), word);
-  }
-
-  // All the chars in the specified word of the range [0, upper).
-  static constexpr uint64_t OpenRangeFromZeroForWord(uint64_t upper,
-                                                     uint64_t word) {
-    return (upper <= 64 * word)
-               ? 0
-               : (upper >= 64 * (word + 1))
-                     ? ~static_cast<uint64_t>(0)
-                     : (~static_cast<uint64_t>(0) >> (64 - upper % 64));
-  }
-
-  static constexpr uint64_t CharMaskForWord(char x, uint64_t word) {
-    const auto unsigned_x = static_cast<unsigned char>(x);
-    return (unsigned_x / 64 == word)
-               ? (static_cast<uint64_t>(1) << (unsigned_x % 64))
-               : 0;
-  }
-
-  void SetChar(char c) {
-    const auto unsigned_c = static_cast<unsigned char>(c);
-    m_[unsigned_c / 64] |= static_cast<uint64_t>(1) << (unsigned_c % 64);
-  }
-
-  uint64_t m_[4];
-};
-
-// Mirror the char-classifying predicates in <cctype>
-constexpr Charmap UpperCharmap() { return Charmap::Range('A', 'Z'); }
-constexpr Charmap LowerCharmap() { return Charmap::Range('a', 'z'); }
-constexpr Charmap DigitCharmap() { return Charmap::Range('0', '9'); }
-constexpr Charmap AlphaCharmap() { return LowerCharmap() | UpperCharmap(); }
-constexpr Charmap AlnumCharmap() { return DigitCharmap() | AlphaCharmap(); }
-constexpr Charmap XDigitCharmap() {
-  return DigitCharmap() | Charmap::Range('A', 'F') | Charmap::Range('a', 'f');
-}
-constexpr Charmap PrintCharmap() { return Charmap::Range(0x20, 0x7e); }
-constexpr Charmap SpaceCharmap() { return Charmap::FromString("\t\n\v\f\r "); }
-constexpr Charmap CntrlCharmap() {
-  return Charmap::Range(0, 0x7f) & ~PrintCharmap();
-}
-constexpr Charmap BlankCharmap() { return Charmap::FromString("\t "); }
-constexpr Charmap GraphCharmap() { return PrintCharmap() & ~SpaceCharmap(); }
-constexpr Charmap PunctCharmap() { return GraphCharmap() & ~AlnumCharmap(); }
-
-}  // namespace strings_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_STRINGS_INTERNAL_CHAR_MAP_H_
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.cc b/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.cc
index b7874385de..57d9d385b3 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.cc
@@ -22,15 +22,12 @@
 #include "absl/strings/internal/cord_rep_btree.h"
 #include "absl/strings/internal/cord_rep_crc.h"
 #include "absl/strings/internal/cord_rep_flat.h"
-#include "absl/strings/internal/cord_rep_ring.h"
 #include "absl/strings/str_cat.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace cord_internal {
 
-ABSL_CONST_INIT std::atomic<bool> cord_ring_buffer_enabled(
-    kCordEnableRingBufferDefault);
 ABSL_CONST_INIT std::atomic<bool> shallow_subcords_enabled(
     kCordShallowSubcordsDefault);
 
@@ -47,9 +44,6 @@ void CordRep::Destroy(CordRep* rep) {
     if (rep->tag == BTREE) {
       CordRepBtree::Destroy(rep->btree());
       return;
-    } else if (rep->tag == RING) {
-      CordRepRing::Destroy(rep->ring());
-      return;
     } else if (rep->tag == EXTERNAL) {
       CordRepExternal::Delete(rep);
       return;
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.h b/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.h
index 20dd008cfa..8744540e2a 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/cord_internal.h
@@ -55,24 +55,15 @@ struct CordRepExternal;
 struct CordRepFlat;
 struct CordRepSubstring;
 struct CordRepCrc;
-class CordRepRing;
 class CordRepBtree;
 
 class CordzInfo;
 
 // Default feature enable states for cord ring buffers
-enum CordFeatureDefaults {
-  kCordEnableRingBufferDefault = false,
-  kCordShallowSubcordsDefault = false
-};
+enum CordFeatureDefaults { kCordShallowSubcordsDefault = false };
 
-extern std::atomic<bool> cord_ring_buffer_enabled;
 extern std::atomic<bool> shallow_subcords_enabled;
 
-inline void enable_cord_ring_buffer(bool enable) {
-  cord_ring_buffer_enabled.store(enable, std::memory_order_relaxed);
-}
-
 inline void enable_shallow_subcords(bool enable) {
   shallow_subcords_enabled.store(enable, std::memory_order_relaxed);
 }
@@ -110,8 +101,16 @@ inline void SmallMemmove(char* dst, const char* src, size_t n) {
     if (nullify_tail) {
       memset(dst + 7, 0, 8);
     }
+    // GCC 12 has a false-positive -Wstringop-overflow warning here.
+#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstringop-overflow"
+#endif
     memcpy(dst, &buf1, 8);
     memcpy(dst + n - 8, &buf2, 8);
+#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
+#pragma GCC diagnostic pop
+#endif
   } else if (n >= 4) {
     uint32_t buf1;
     uint32_t buf2;
@@ -158,18 +157,18 @@ class RefcountAndFlags {
   // false.  Always returns false when the immortal bit is set.
   inline bool Decrement() {
     int32_t refcount = count_.load(std::memory_order_acquire);
-    assert((refcount & kRefcountMask) > 0 || refcount & kImmortalFlag);
+    assert(refcount > 0 || refcount & kImmortalFlag);
     return refcount != kRefIncrement &&
-           (count_.fetch_sub(kRefIncrement, std::memory_order_acq_rel) &
-            kHighRefcountMask) != 0;
+           count_.fetch_sub(kRefIncrement, std::memory_order_acq_rel) !=
+               kRefIncrement;
   }
 
   // Same as Decrement but expect that refcount is greater than 1.
   inline bool DecrementExpectHighRefcount() {
     int32_t refcount =
         count_.fetch_sub(kRefIncrement, std::memory_order_acq_rel);
-    assert((refcount & kRefcountMask) > 0 || refcount & kImmortalFlag);
-    return (refcount & kHighRefcountMask) != 0;
+    assert(refcount > 0 || refcount & kImmortalFlag);
+    return refcount != kRefIncrement;
   }
 
   // Returns the current reference count using acquire semantics.
@@ -185,10 +184,9 @@ class RefcountAndFlags {
   // This call performs the test for a reference count of one, and
   // performs the memory barrier needed for the owning thread
   // to act on the object, knowing that it has exclusive access to the
-  // object.  Always returns false when the immortal bit is set.
+  // object. Always returns false when the immortal bit is set.
   inline bool IsOne() {
-    return (count_.load(std::memory_order_acquire) & kRefcountMask) ==
-           kRefIncrement;
+    return count_.load(std::memory_order_acquire) == kRefIncrement;
   }
 
   bool IsImmortal() const {
@@ -196,32 +194,15 @@ class RefcountAndFlags {
   }
 
  private:
-  // We reserve the bottom bits for flags.
+  // We reserve the bottom bit for flag.
   // kImmortalBit indicates that this entity should never be collected; it is
   // used for the StringConstant constructor to avoid collecting immutable
   // constant cords.
-  // kReservedFlag is reserved for future use.
   enum Flags {
-    kNumFlags = 2,
+    kNumFlags = 1,
 
     kImmortalFlag = 0x1,
-    kReservedFlag = 0x2,
     kRefIncrement = (1 << kNumFlags),
-
-    // Bitmask to use when checking refcount by equality.  This masks out
-    // all flags except kImmortalFlag, which is part of the refcount for
-    // purposes of equality.  (A refcount of 0 or 1 does not count as 0 or 1
-    // if the immortal bit is set.)
-    kRefcountMask = ~kReservedFlag,
-
-    // Bitmask to use when checking if refcount is equal to 1 and not
-    // immortal when decrementing the refcount. This masks out kRefIncrement and
-    // all flags except kImmortalFlag. If the masked RefcountAndFlags is 0, we
-    // assume the refcount is equal to 1, since we know it's not immortal and
-    // not greater than 1. If the masked RefcountAndFlags is not 0, we can
-    // assume the refcount is not equal to 1 since either a higher bit in the
-    // refcount is set, or kImmortal is set.
-    kHighRefcountMask = kRefcountMask & ~kRefIncrement,
   };
 
   std::atomic<int32_t> count_;
@@ -233,7 +214,7 @@ enum CordRepKind {
   SUBSTRING = 1,
   CRC = 2,
   BTREE = 3,
-  RING = 4,
+  UNUSED_4 = 4,
   EXTERNAL = 5,
 
   // We have different tags for different sized flat arrays,
@@ -252,12 +233,8 @@ enum CordRepKind {
 // There are various locations where we want to check if some rep is a 'plain'
 // data edge, i.e. an external or flat rep. By having FLAT == EXTERNAL + 1, we
 // can perform this check in a single branch as 'tag >= EXTERNAL'
-// Likewise, we have some locations where we check for 'ring or external/flat',
-// so likewise align RING to EXTERNAL.
 // Note that we can leave this optimization to the compiler. The compiler will
 // DTRT when it sees a condition like `tag == EXTERNAL || tag >= FLAT`.
-static_assert(RING == BTREE + 1, "BTREE and RING not consecutive");
-static_assert(EXTERNAL == RING + 1, "BTREE and EXTERNAL not consecutive");
 static_assert(FLAT == EXTERNAL + 1, "EXTERNAL and FLAT not consecutive");
 
 struct CordRep {
@@ -301,15 +278,12 @@ struct CordRep {
   // # LINT.ThenChange(cord_rep_btree.h:copy_raw)
 
   // Returns true if this instance's tag matches the requested type.
-  constexpr bool IsRing() const { return tag == RING; }
   constexpr bool IsSubstring() const { return tag == SUBSTRING; }
   constexpr bool IsCrc() const { return tag == CRC; }
   constexpr bool IsExternal() const { return tag == EXTERNAL; }
   constexpr bool IsFlat() const { return tag >= FLAT; }
   constexpr bool IsBtree() const { return tag == BTREE; }
 
-  inline CordRepRing* ring();
-  inline const CordRepRing* ring() const;
   inline CordRepSubstring* substring();
   inline const CordRepSubstring* substring() const;
   inline CordRepCrc* crc();
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_rep_ring.cc b/contrib/restricted/abseil-cpp/absl/strings/internal/cord_rep_ring.cc
deleted file mode 100644
index af2fc7683d..0000000000
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_rep_ring.cc
+++ /dev/null
@@ -1,773 +0,0 @@
-// Copyright 2020 The Abseil Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-#include "absl/strings/internal/cord_rep_ring.h"
-
-#include <cassert>
-#include <cstddef>
-#include <cstdint>
-#include <iostream>
-#include <limits>
-#include <memory>
-#include <string>
-
-#include "absl/base/internal/raw_logging.h"
-#include "absl/base/internal/throw_delegate.h"
-#include "absl/base/macros.h"
-#include "absl/container/inlined_vector.h"
-#include "absl/strings/internal/cord_internal.h"
-#include "absl/strings/internal/cord_rep_consume.h"
-#include "absl/strings/internal/cord_rep_flat.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace cord_internal {
-
-namespace {
-
-using index_type = CordRepRing::index_type;
-
-enum class Direction { kForward, kReversed };
-
-inline bool IsFlatOrExternal(CordRep* rep) {
-  return rep->IsFlat() || rep->IsExternal();
-}
-
-// Verifies that n + extra <= kMaxCapacity: throws std::length_error otherwise.
-inline void CheckCapacity(size_t n, size_t extra) {
-  if (ABSL_PREDICT_FALSE(extra > CordRepRing::kMaxCapacity - n)) {
-    base_internal::ThrowStdLengthError("Maximum capacity exceeded");
-  }
-}
-
-// Creates a flat from the provided string data, allocating up to `extra`
-// capacity in the returned flat depending on kMaxFlatLength limitations.
-// Requires `len` to be less or equal to `kMaxFlatLength`
-CordRepFlat* CreateFlat(const char* s, size_t n, size_t extra = 0) {  // NOLINT
-  assert(n <= kMaxFlatLength);
-  auto* rep = CordRepFlat::New(n + extra);
-  rep->length = n;
-  memcpy(rep->Data(), s, n);
-  return rep;
-}
-
-// Unrefs the entries in `[head, tail)`.
-// Requires all entries to be a FLAT or EXTERNAL node.
-void UnrefEntries(const CordRepRing* rep, index_type head, index_type tail) {
-  rep->ForEach(head, tail, [rep](index_type ix) {
-    CordRep* child = rep->entry_child(ix);
-    if (!child->refcount.Decrement()) {
-      if (child->tag >= FLAT) {
-        CordRepFlat::Delete(child->flat());
-      } else {
-        CordRepExternal::Delete(child->external());
-      }
-    }
-  });
-}
-
-}  // namespace
-
-std::ostream& operator<<(std::ostream& s, const CordRepRing& rep) {
-  // Note: 'pos' values are defined as size_t (for overflow reasons), but that
-  // prints really awkward for small prepended values such as -5. ssize_t is not
-  // portable (POSIX), so we use ptrdiff_t instead to cast to signed values.
-  s << "  CordRepRing(" << &rep << ", length = " << rep.length
-    << ", head = " << rep.head_ << ", tail = " << rep.tail_
-    << ", cap = " << rep.capacity_ << ", rc = " << rep.refcount.Get()
-    << ", begin_pos_ = " << static_cast<ptrdiff_t>(rep.begin_pos_) << ") {\n";
-  CordRepRing::index_type head = rep.head();
-  do {
-    CordRep* child = rep.entry_child(head);
-    s << " entry[" << head << "] length = " << rep.entry_length(head)
-      << ", child " << child << ", clen = " << child->length
-      << ", tag = " << static_cast<int>(child->tag)
-      << ", rc = " << child->refcount.Get()
-      << ", offset = " << rep.entry_data_offset(head)
-      << ", end_pos = " << static_cast<ptrdiff_t>(rep.entry_end_pos(head))
-      << "\n";
-    head = rep.advance(head);
-  } while (head != rep.tail());
-  return s << "}\n";
-}
-
-void CordRepRing::AddDataOffset(index_type index, size_t n) {
-  entry_data_offset()[index] += static_cast<offset_type>(n);
-}
-
-void CordRepRing::SubLength(index_type index, size_t n) {
-  entry_end_pos()[index] -= n;
-}
-
-class CordRepRing::Filler {
- public:
-  Filler(CordRepRing* rep, index_type pos) : rep_(rep), head_(pos), pos_(pos) {}
-
-  index_type head() const { return head_; }
-  index_type pos() const { return pos_; }
-
-  void Add(CordRep* child, size_t offset, pos_type end_pos) {
-    rep_->entry_end_pos()[pos_] = end_pos;
-    rep_->entry_child()[pos_] = child;
-    rep_->entry_data_offset()[pos_] = static_cast<offset_type>(offset);
-    pos_ = rep_->advance(pos_);
-  }
-
- private:
-  CordRepRing* rep_;
-  index_type head_;
-  index_type pos_;
-};
-
-#ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
-constexpr size_t CordRepRing::kMaxCapacity;
-#endif
-
-bool CordRepRing::IsValid(std::ostream& output) const {
-  if (capacity_ == 0) {
-    output << "capacity == 0";
-    return false;
-  }
-
-  if (head_ >= capacity_ || tail_ >= capacity_) {
-    output << "head " << head_ << " and/or tail " << tail_ << "exceed capacity "
-           << capacity_;
-    return false;
-  }
-
-  const index_type back = retreat(tail_);
-  size_t pos_length = Distance(begin_pos_, entry_end_pos(back));
-  if (pos_length != length) {
-    output << "length " << length << " does not match positional length "
-           << pos_length << " from begin_pos " << begin_pos_ << " and entry["
-           << back << "].end_pos " << entry_end_pos(back);
-    return false;
-  }
-
-  index_type head = head_;
-  pos_type begin_pos = begin_pos_;
-  do {
-    pos_type end_pos = entry_end_pos(head);
-    size_t entry_length = Distance(begin_pos, end_pos);
-    if (entry_length == 0) {
-      output << "entry[" << head << "] has an invalid length " << entry_length
-             << " from begin_pos " << begin_pos << " and end_pos " << end_pos;
-      return false;
-    }
-
-    CordRep* child = entry_child(head);
-    if (child == nullptr) {
-      output << "entry[" << head << "].child == nullptr";
-      return false;
-    }
-    if (child->tag < FLAT && child->tag != EXTERNAL) {
-      output << "entry[" << head << "].child has an invalid tag "
-             << static_cast<int>(child->tag);
-      return false;
-    }
-
-    size_t offset = entry_data_offset(head);
-    if (offset >= child->length || entry_length > child->length - offset) {
-      output << "entry[" << head << "] has offset " << offset
-             << " and entry length " << entry_length
-             << " which are outside of the child's length of " << child->length;
-      return false;
-    }
-
-    begin_pos = end_pos;
-    head = advance(head);
-  } while (head != tail_);
-
-  return true;
-}
-
-#ifdef EXTRA_CORD_RING_VALIDATION
-CordRepRing* CordRepRing::Validate(CordRepRing* rep, const char* file,
-                                   int line) {
-  if (!rep->IsValid(std::cerr)) {
-    std::cerr << "\nERROR: CordRepRing corrupted";
-    if (line) std::cerr << " at line " << line;
-    if (file) std::cerr << " in file " << file;
-    std::cerr << "\nContent = " << *rep;
-    abort();
-  }
-  return rep;
-}
-#endif  // EXTRA_CORD_RING_VALIDATION
-
-CordRepRing* CordRepRing::New(size_t capacity, size_t extra) {
-  CheckCapacity(capacity, extra);
-
-  size_t size = AllocSize(capacity += extra);
-  void* mem = ::operator new(size);
-  auto* rep = new (mem) CordRepRing(static_cast<index_type>(capacity));
-  rep->tag = RING;
-  rep->capacity_ = static_cast<index_type>(capacity);
-  rep->begin_pos_ = 0;
-  return rep;
-}
-
-void CordRepRing::SetCapacityForTesting(size_t capacity) {
-  // Adjust for the changed layout
-  assert(capacity <= capacity_);
-  assert(head() == 0 || head() < tail());
-  memmove(Layout::Partial(capacity).Pointer<1>(data_) + head(),
-          Layout::Partial(capacity_).Pointer<1>(data_) + head(),
-          entries() * sizeof(Layout::ElementType<1>));
-  memmove(Layout::Partial(capacity, capacity).Pointer<2>(data_) + head(),
-          Layout::Partial(capacity_, capacity_).Pointer<2>(data_) + head(),
-          entries() * sizeof(Layout::ElementType<2>));
-  capacity_ = static_cast<index_type>(capacity);
-}
-
-void CordRepRing::Delete(CordRepRing* rep) {
-  assert(rep != nullptr && rep->IsRing());
-#if defined(__cpp_sized_deallocation)
-  size_t size = AllocSize(rep->capacity_);
-  rep->~CordRepRing();
-  ::operator delete(rep, size);
-#else
-  rep->~CordRepRing();
-  ::operator delete(rep);
-#endif
-}
-
-void CordRepRing::Destroy(CordRepRing* rep) {
-  UnrefEntries(rep, rep->head(), rep->tail());
-  Delete(rep);
-}
-
-template <bool ref>
-void CordRepRing::Fill(const CordRepRing* src, index_type head,
-                       index_type tail) {
-  this->length = src->length;
-  head_ = 0;
-  tail_ = advance(0, src->entries(head, tail));
-  begin_pos_ = src->begin_pos_;
-
-  // TODO(mvels): there may be opportunities here for large buffers.
-  auto* dst_pos = entry_end_pos();
-  auto* dst_child = entry_child();
-  auto* dst_offset = entry_data_offset();
-  src->ForEach(head, tail, [&](index_type index) {
-    *dst_pos++ = src->entry_end_pos(index);
-    CordRep* child = src->entry_child(index);
-    *dst_child++ = ref ? CordRep::Ref(child) : child;
-    *dst_offset++ = src->entry_data_offset(index);
-  });
-}
-
-CordRepRing* CordRepRing::Copy(CordRepRing* rep, index_type head,
-                               index_type tail, size_t extra) {
-  CordRepRing* newrep = CordRepRing::New(rep->entries(head, tail), extra);
-  newrep->Fill<true>(rep, head, tail);
-  CordRep::Unref(rep);
-  return newrep;
-}
-
-CordRepRing* CordRepRing::Mutable(CordRepRing* rep, size_t extra) {
-  // Get current number of entries, and check for max capacity.
-  size_t entries = rep->entries();
-
-  if (!rep->refcount.IsOne()) {
-    return Copy(rep, rep->head(), rep->tail(), extra);
-  } else if (entries + extra > rep->capacity()) {
-    const size_t min_grow = rep->capacity() + rep->capacity() / 2;
-    const size_t min_extra = (std::max)(extra, min_grow - entries);
-    CordRepRing* newrep = CordRepRing::New(entries, min_extra);
-    newrep->Fill<false>(rep, rep->head(), rep->tail());
-    CordRepRing::Delete(rep);
-    return newrep;
-  } else {
-    return rep;
-  }
-}
-
-Span<char> CordRepRing::GetAppendBuffer(size_t size) {
-  assert(refcount.IsOne());
-  index_type back = retreat(tail_);
-  CordRep* child = entry_child(back);
-  if (child->tag >= FLAT && child->refcount.IsOne()) {
-    size_t capacity = child->flat()->Capacity();
-    pos_type end_pos = entry_end_pos(back);
-    size_t data_offset = entry_data_offset(back);
-    size_t entry_length = Distance(entry_begin_pos(back), end_pos);
-    size_t used = data_offset + entry_length;
-    if (size_t n = (std::min)(capacity - used, size)) {
-      child->length = data_offset + entry_length + n;
-      entry_end_pos()[back] = end_pos + n;
-      this->length += n;
-      return {child->flat()->Data() + used, n};
-    }
-  }
-  return {nullptr, 0};
-}
-
-Span<char> CordRepRing::GetPrependBuffer(size_t size) {
-  assert(refcount.IsOne());
-  CordRep* child = entry_child(head_);
-  size_t data_offset = entry_data_offset(head_);
-  if (data_offset && child->refcount.IsOne() && child->tag >= FLAT) {
-    size_t n = (std::min)(data_offset, size);
-    this->length += n;
-    begin_pos_ -= n;
-    data_offset -= n;
-    entry_data_offset()[head_] = static_cast<offset_type>(data_offset);
-    return {child->flat()->Data() + data_offset, n};
-  }
-  return {nullptr, 0};
-}
-
-CordRepRing* CordRepRing::CreateFromLeaf(CordRep* child, size_t offset,
-                                         size_t len, size_t extra) {
-  CordRepRing* rep = CordRepRing::New(1, extra);
-  rep->head_ = 0;
-  rep->tail_ = rep->advance(0);
-  rep->length = len;
-  rep->entry_end_pos()[0] = len;
-  rep->entry_child()[0] = child;
-  rep->entry_data_offset()[0] = static_cast<offset_type>(offset);
-  return Validate(rep);
-}
-
-CordRepRing* CordRepRing::CreateSlow(CordRep* child, size_t extra) {
-  CordRepRing* rep = nullptr;
-  Consume(child, [&](CordRep* child_arg, size_t offset, size_t len) {
-    if (IsFlatOrExternal(child_arg)) {
-      rep = rep ? AppendLeaf(rep, child_arg, offset, len)
-                : CreateFromLeaf(child_arg, offset, len, extra);
-    } else if (rep) {
-      rep = AddRing<AddMode::kAppend>(rep, child_arg->ring(), offset, len);
-    } else if (offset == 0 && child_arg->length == len) {
-      rep = Mutable(child_arg->ring(), extra);
-    } else {
-      rep = SubRing(child_arg->ring(), offset, len, extra);
-    }
-  });
-  return Validate(rep, nullptr, __LINE__);
-}
-
-CordRepRing* CordRepRing::Create(CordRep* child, size_t extra) {
-  size_t length = child->length;
-  if (IsFlatOrExternal(child)) {
-    return CreateFromLeaf(child, 0, length, extra);
-  }
-  if (child->IsRing()) {
-    return Mutable(child->ring(), extra);
-  }
-  return CreateSlow(child, extra);
-}
-
-template <CordRepRing::AddMode mode>
-CordRepRing* CordRepRing::AddRing(CordRepRing* rep, CordRepRing* ring,
-                                  size_t offset, size_t len) {
-  assert(offset < ring->length);
-  constexpr bool append = mode == AddMode::kAppend;
-  Position head = ring->Find(offset);
-  Position tail = ring->FindTail(head.index, offset + len);
-  const index_type entries = ring->entries(head.index, tail.index);
-
-  rep = Mutable(rep, entries);
-
-  // The delta for making ring[head].end_pos into 'len - offset'
-  const pos_type delta_length =
-      (append ? rep->begin_pos_ + rep->length : rep->begin_pos_ - len) -
-      ring->entry_begin_pos(head.index) - head.offset;
-
-  // Start filling at `tail`, or `entries` before `head`
-  Filler filler(rep, append ? rep->tail_ : rep->retreat(rep->head_, entries));
-
-  if (ring->refcount.IsOne()) {
-    // Copy entries from source stealing the ref and adjusting the end position.
-    // Commit the filler as this is no-op.
-    ring->ForEach(head.index, tail.index, [&](index_type ix) {
-      filler.Add(ring->entry_child(ix), ring->entry_data_offset(ix),
-                 ring->entry_end_pos(ix) + delta_length);
-    });
-
-    // Unref entries we did not copy over, and delete source.
-    if (head.index != ring->head_) UnrefEntries(ring, ring->head_, head.index);
-    if (tail.index != ring->tail_) UnrefEntries(ring, tail.index, ring->tail_);
-    CordRepRing::Delete(ring);
-  } else {
-    ring->ForEach(head.index, tail.index, [&](index_type ix) {
-      CordRep* child = ring->entry_child(ix);
-      filler.Add(child, ring->entry_data_offset(ix),
-                 ring->entry_end_pos(ix) + delta_length);
-      CordRep::Ref(child);
-    });
-    CordRepRing::Unref(ring);
-  }
-
-  if (head.offset) {
-    // Increase offset of first 'source' entry appended or prepended.
-    // This is always the entry in `filler.head()`
-    rep->AddDataOffset(filler.head(), head.offset);
-  }
-
-  if (tail.offset) {
-    // Reduce length of last 'source' entry appended or prepended.
-    // This is always the entry tailed by `filler.pos()`
-    rep->SubLength(rep->retreat(filler.pos()), tail.offset);
-  }
-
-  // Commit changes
-  rep->length += len;
-  if (append) {
-    rep->tail_ = filler.pos();
-  } else {
-    rep->head_ = filler.head();
-    rep->begin_pos_ -= len;
-  }
-
-  return Validate(rep);
-}
-
-CordRepRing* CordRepRing::AppendSlow(CordRepRing* rep, CordRep* child) {
-  Consume(child, [&rep](CordRep* child_arg, size_t offset, size_t len) {
-    if (child_arg->IsRing()) {
-      rep = AddRing<AddMode::kAppend>(rep, child_arg->ring(), offset, len);
-    } else {
-      rep = AppendLeaf(rep, child_arg, offset, len);
-    }
-  });
-  return rep;
-}
-
-CordRepRing* CordRepRing::AppendLeaf(CordRepRing* rep, CordRep* child,
-                                     size_t offset, size_t len) {
-  rep = Mutable(rep, 1);
-  index_type back = rep->tail_;
-  const pos_type begin_pos = rep->begin_pos_ + rep->length;
-  rep->tail_ = rep->advance(rep->tail_);
-  rep->length += len;
-  rep->entry_end_pos()[back] = begin_pos + len;
-  rep->entry_child()[back] = child;
-  rep->entry_data_offset()[back] = static_cast<offset_type>(offset);
-  return Validate(rep, nullptr, __LINE__);
-}
-
-CordRepRing* CordRepRing::Append(CordRepRing* rep, CordRep* child) {
-  size_t length = child->length;
-  if (IsFlatOrExternal(child)) {
-    return AppendLeaf(rep, child, 0, length);
-  }
-  if (child->IsRing()) {
-    return AddRing<AddMode::kAppend>(rep, child->ring(), 0, length);
-  }
-  return AppendSlow(rep, child);
-}
-
-CordRepRing* CordRepRing::PrependSlow(CordRepRing* rep, CordRep* child) {
-  ReverseConsume(child, [&](CordRep* child_arg, size_t offset, size_t len) {
-    if (IsFlatOrExternal(child_arg)) {
-      rep = PrependLeaf(rep, child_arg, offset, len);
-    } else {
-      rep = AddRing<AddMode::kPrepend>(rep, child_arg->ring(), offset, len);
-    }
-  });
-  return Validate(rep);
-}
-
-CordRepRing* CordRepRing::PrependLeaf(CordRepRing* rep, CordRep* child,
-                                      size_t offset, size_t len) {
-  rep = Mutable(rep, 1);
-  index_type head = rep->retreat(rep->head_);
-  pos_type end_pos = rep->begin_pos_;
-  rep->head_ = head;
-  rep->length += len;
-  rep->begin_pos_ -= len;
-  rep->entry_end_pos()[head] = end_pos;
-  rep->entry_child()[head] = child;
-  rep->entry_data_offset()[head] = static_cast<offset_type>(offset);
-  return Validate(rep);
-}
-
-CordRepRing* CordRepRing::Prepend(CordRepRing* rep, CordRep* child) {
-  size_t length = child->length;
-  if (IsFlatOrExternal(child)) {
-    return PrependLeaf(rep, child, 0, length);
-  }
-  if (child->IsRing()) {
-    return AddRing<AddMode::kPrepend>(rep, child->ring(), 0, length);
-  }
-  return PrependSlow(rep, child);
-}
-
-CordRepRing* CordRepRing::Append(CordRepRing* rep, absl::string_view data,
-                                 size_t extra) {
-  if (rep->refcount.IsOne()) {
-    Span<char> avail = rep->GetAppendBuffer(data.length());
-    if (!avail.empty()) {
-      memcpy(avail.data(), data.data(), avail.length());
-      data.remove_prefix(avail.length());
-    }
-  }
-  if (data.empty()) return Validate(rep);
-
-  const size_t flats = (data.length() - 1) / kMaxFlatLength + 1;
-  rep = Mutable(rep, flats);
-
-  Filler filler(rep, rep->tail_);
-  pos_type pos = rep->begin_pos_ + rep->length;
-
-  while (data.length() >= kMaxFlatLength) {
-    auto* flat = CreateFlat(data.data(), kMaxFlatLength);
-    filler.Add(flat, 0, pos += kMaxFlatLength);
-    data.remove_prefix(kMaxFlatLength);
-  }
-
-  if (data.length()) {
-    auto* flat = CreateFlat(data.data(), data.length(), extra);
-    filler.Add(flat, 0, pos += data.length());
-  }
-
-  rep->length = pos - rep->begin_pos_;
-  rep->tail_ = filler.pos();
-
-  return Validate(rep);
-}
-
-CordRepRing* CordRepRing::Prepend(CordRepRing* rep, absl::string_view data,
-                                  size_t extra) {
-  if (rep->refcount.IsOne()) {
-    Span<char> avail = rep->GetPrependBuffer(data.length());
-    if (!avail.empty()) {
-      const char* tail = data.data() + data.length() - avail.length();
-      memcpy(avail.data(), tail, avail.length());
-      data.remove_suffix(avail.length());
-    }
-  }
-  if (data.empty()) return rep;
-
-  const size_t flats = (data.length() - 1) / kMaxFlatLength + 1;
-  rep = Mutable(rep, flats);
-  pos_type pos = rep->begin_pos_;
-  Filler filler(rep, rep->retreat(rep->head_, static_cast<index_type>(flats)));
-
-  size_t first_size = data.size() - (flats - 1) * kMaxFlatLength;
-  CordRepFlat* flat = CordRepFlat::New(first_size + extra);
-  flat->length = first_size + extra;
-  memcpy(flat->Data() + extra, data.data(), first_size);
-  data.remove_prefix(first_size);
-  filler.Add(flat, extra, pos);
-  pos -= first_size;
-
-  while (!data.empty()) {
-    assert(data.size() >= kMaxFlatLength);
-    flat = CreateFlat(data.data(), kMaxFlatLength);
-    filler.Add(flat, 0, pos);
-    pos -= kMaxFlatLength;
-    data.remove_prefix(kMaxFlatLength);
-  }
-
-  rep->head_ = filler.head();
-  rep->length += rep->begin_pos_ - pos;
-  rep->begin_pos_ = pos;
-
-  return Validate(rep);
-}
-
-// 32 entries is 32 * sizeof(pos_type) = 4 cache lines on x86
-static constexpr index_type kBinarySearchThreshold = 32;
-static constexpr index_type kBinarySearchEndCount = 8;
-
-template <bool wrap>
-CordRepRing::index_type CordRepRing::FindBinary(index_type head,
-                                                index_type tail,
-                                                size_t offset) const {
-  index_type count = tail + (wrap ? capacity_ : 0) - head;
-  do {
-    count = (count - 1) / 2;
-    assert(count < entries(head, tail_));
-    index_type mid = wrap ? advance(head, count) : head + count;
-    index_type after_mid = wrap ? advance(mid) : mid + 1;
-    bool larger = (offset >= entry_end_offset(mid));
-    head = larger ? after_mid : head;
-    tail = larger ? tail : mid;
-    assert(head != tail);
-  } while (ABSL_PREDICT_TRUE(count > kBinarySearchEndCount));
-  return head;
-}
-
-CordRepRing::Position CordRepRing::FindSlow(index_type head,
-                                            size_t offset) const {
-  index_type tail = tail_;
-
-  // Binary search until we are good for linear search
-  // Optimize for branchless / non wrapping ops
-  if (tail > head) {
-    index_type count = tail - head;
-    if (count > kBinarySearchThreshold) {
-      head = FindBinary<false>(head, tail, offset);
-    }
-  } else {
-    index_type count = capacity_ + tail - head;
-    if (count > kBinarySearchThreshold) {
-      head = FindBinary<true>(head, tail, offset);
-    }
-  }
-
-  pos_type pos = entry_begin_pos(head);
-  pos_type end_pos = entry_end_pos(head);
-  while (offset >= Distance(begin_pos_, end_pos)) {
-    head = advance(head);
-    pos = end_pos;
-    end_pos = entry_end_pos(head);
-  }
-
-  return {head, offset - Distance(begin_pos_, pos)};
-}
-
-CordRepRing::Position CordRepRing::FindTailSlow(index_type head,
-                                                size_t offset) const {
-  index_type tail = tail_;
-  const size_t tail_offset = offset - 1;
-
-  // Binary search until we are good for linear search
-  // Optimize for branchless / non wrapping ops
-  if (tail > head) {
-    index_type count = tail - head;
-    if (count > kBinarySearchThreshold) {
-      head = FindBinary<false>(head, tail, tail_offset);
-    }
-  } else {
-    index_type count = capacity_ + tail - head;
-    if (count > kBinarySearchThreshold) {
-      head = FindBinary<true>(head, tail, tail_offset);
-    }
-  }
-
-  size_t end_offset = entry_end_offset(head);
-  while (tail_offset >= end_offset) {
-    head = advance(head);
-    end_offset = entry_end_offset(head);
-  }
-
-  return {advance(head), end_offset - offset};
-}
-
-char CordRepRing::GetCharacter(size_t offset) const {
-  assert(offset < length);
-
-  Position pos = Find(offset);
-  size_t data_offset = entry_data_offset(pos.index) + pos.offset;
-  return GetRepData(entry_child(pos.index))[data_offset];
-}
-
-CordRepRing* CordRepRing::SubRing(CordRepRing* rep, size_t offset,
-                                  size_t len, size_t extra) {
-  assert(offset <= rep->length);
-  assert(offset <= rep->length - len);
-
-  if (len == 0) {
-    CordRep::Unref(rep);
-    return nullptr;
-  }
-
-  // Find position of first byte
-  Position head = rep->Find(offset);
-  Position tail = rep->FindTail(head.index, offset + len);
-  const size_t new_entries = rep->entries(head.index, tail.index);
-
-  if (rep->refcount.IsOne() && extra <= (rep->capacity() - new_entries)) {
-    // We adopt a privately owned rep and no extra entries needed.
-    if (head.index != rep->head_) UnrefEntries(rep, rep->head_, head.index);
-    if (tail.index != rep->tail_) UnrefEntries(rep, tail.index, rep->tail_);
-    rep->head_ = head.index;
-    rep->tail_ = tail.index;
-  } else {
-    // Copy subset to new rep
-    rep = Copy(rep, head.index, tail.index, extra);
-    head.index = rep->head_;
-    tail.index = rep->tail_;
-  }
-
-  // Adjust begin_pos and length
-  rep->length = len;
-  rep->begin_pos_ += offset;
-
-  // Adjust head and tail blocks
-  if (head.offset) {
-    rep->AddDataOffset(head.index, head.offset);
-  }
-  if (tail.offset) {
-    rep->SubLength(rep->retreat(tail.index), tail.offset);
-  }
-
-  return Validate(rep);
-}
-
-CordRepRing* CordRepRing::RemovePrefix(CordRepRing* rep, size_t len,
-                                       size_t extra) {
-  assert(len <= rep->length);
-  if (len == rep->length) {
-    CordRep::Unref(rep);
-    return nullptr;
-  }
-
-  Position head = rep->Find(len);
-  if (rep->refcount.IsOne()) {
-    if (head.index != rep->head_) UnrefEntries(rep, rep->head_, head.index);
-    rep->head_ = head.index;
-  } else {
-    rep = Copy(rep, head.index, rep->tail_, extra);
-    head.index = rep->head_;
-  }
-
-  // Adjust begin_pos and length
-  rep->length -= len;
-  rep->begin_pos_ += len;
-
-  // Adjust head block
-  if (head.offset) {
-    rep->AddDataOffset(head.index, head.offset);
-  }
-
-  return Validate(rep);
-}
-
-CordRepRing* CordRepRing::RemoveSuffix(CordRepRing* rep, size_t len,
-                                       size_t extra) {
-  assert(len <= rep->length);
-
-  if (len == rep->length) {
-    CordRep::Unref(rep);
-    return nullptr;
-  }
-
-  Position tail = rep->FindTail(rep->length - len);
-  if (rep->refcount.IsOne()) {
-    // We adopt a privately owned rep, scrub.
-    if (tail.index != rep->tail_) UnrefEntries(rep, tail.index, rep->tail_);
-    rep->tail_ = tail.index;
-  } else {
-    // Copy subset to new rep
-    rep = Copy(rep, rep->head_, tail.index, extra);
-    tail.index = rep->tail_;
-  }
-
-  // Adjust length
-  rep->length -= len;
-
-  // Adjust tail block
-  if (tail.offset) {
-    rep->SubLength(rep->retreat(tail.index), tail.offset);
-  }
-
-  return Validate(rep);
-}
-
-}  // namespace cord_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_rep_ring.h b/contrib/restricted/abseil-cpp/absl/strings/internal/cord_rep_ring.h
deleted file mode 100644
index 79a2fdb1c3..0000000000
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/cord_rep_ring.h
+++ /dev/null
@@ -1,607 +0,0 @@
-// Copyright 2020 The Abseil Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef ABSL_STRINGS_INTERNAL_CORD_REP_RING_H_
-#define ABSL_STRINGS_INTERNAL_CORD_REP_RING_H_
-
-#include <cassert>
-#include <cstddef>
-#include <cstdint>
-#include <iosfwd>
-#include <limits>
-#include <memory>
-
-#include "absl/container/internal/layout.h"
-#include "absl/strings/internal/cord_internal.h"
-#include "absl/strings/internal/cord_rep_flat.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace cord_internal {
-
-// All operations modifying a ring buffer are implemented as static methods
-// requiring a CordRepRing instance with a reference adopted by the method.
-//
-// The methods return the modified ring buffer, which may be equal to the input
-// if the input was not shared, and having large enough capacity to accommodate
-// any newly added node(s). Otherwise, a copy of the input rep with the new
-// node(s) added is returned.
-//
-// Any modification on non shared ring buffers with enough capacity will then
-// require minimum atomic operations. Caller should where possible provide
-// reasonable `extra` hints for both anticipated extra `flat` byte space, as
-// well as anticipated extra nodes required for complex operations.
-//
-// Example of code creating a ring buffer, adding some data to it,
-// and discarding the buffer when done:
-//
-//   void FunWithRings() {
-//     // Create ring with 3 flats
-//     CordRep* flat = CreateFlat("Hello");
-//     CordRepRing* ring = CordRepRing::Create(flat, 2);
-//     ring = CordRepRing::Append(ring, CreateFlat(" "));
-//     ring = CordRepRing::Append(ring, CreateFlat("world"));
-//     DoSomethingWithRing(ring);
-//     CordRep::Unref(ring);
-//   }
-//
-// Example of code Copying an existing ring buffer and modifying it:
-//
-//   void MoreFunWithRings(CordRepRing* src) {
-//     CordRepRing* ring = CordRep::Ref(src)->ring();
-//     ring = CordRepRing::Append(ring, CreateFlat("Hello"));
-//     ring = CordRepRing::Append(ring, CreateFlat(" "));
-//     ring = CordRepRing::Append(ring, CreateFlat("world"));
-//     DoSomethingWithRing(ring);
-//     CordRep::Unref(ring);
-//   }
-//
-class CordRepRing : public CordRep {
- public:
-  // `pos_type` represents a 'logical position'. A CordRepRing instance has a
-  // `begin_pos` (default 0), and each node inside the buffer will have an
-  // `end_pos` which is the `end_pos` of the previous node (or `begin_pos`) plus
-  // this node's length. The purpose is to allow for a binary search on this
-  // position, while allowing O(1) prepend and append operations.
-  using pos_type = size_t;
-
-  // `index_type` is the type for the `head`, `tail` and `capacity` indexes.
-  // Ring buffers are limited to having no more than four billion entries.
-  using index_type = uint32_t;
-
-  // `offset_type` is the type for the data offset inside a child rep's data.
-  using offset_type = uint32_t;
-
-  // Position holds the node index and relative offset into the node for
-  // some physical offset in the contained data as returned by the Find()
-  // and FindTail() methods.
-  struct Position {
-    index_type index;
-    size_t offset;
-  };
-
-  // The maximum # of child nodes that can be hosted inside a CordRepRing.
-  static constexpr size_t kMaxCapacity = (std::numeric_limits<uint32_t>::max)();
-
-  // CordRepring can not be default constructed, moved, copied or assigned.
-  CordRepRing() = delete;
-  CordRepRing(const CordRepRing&) = delete;
-  CordRepRing& operator=(const CordRepRing&) = delete;
-
-  // Returns true if this instance is valid, false if some or all of the
-  // invariants are broken. Intended for debug purposes only.
-  // `output` receives an explanation of the broken invariants.
-  bool IsValid(std::ostream& output) const;
-
-  // Returns the size in bytes for a CordRepRing with `capacity' entries.
-  static constexpr size_t AllocSize(size_t capacity);
-
-  // Returns the distance in bytes from `pos` to `end_pos`.
-  static constexpr size_t Distance(pos_type pos, pos_type end_pos);
-
-  // Creates a new ring buffer from the provided `rep`. Adopts a reference
-  // on `rep`. The returned ring buffer has a capacity of at least `extra + 1`
-  static CordRepRing* Create(CordRep* child, size_t extra = 0);
-
-  // `head`, `tail` and `capacity` indexes defining the ring buffer boundaries.
-  index_type head() const { return head_; }
-  index_type tail() const { return tail_; }
-  index_type capacity() const { return capacity_; }
-
-  // Returns the number of entries in this instance.
-  index_type entries() const { return entries(head_, tail_); }
-
-  // Returns the logical begin position of this instance.
-  pos_type begin_pos() const { return begin_pos_; }
-
-  // Returns the number of entries for a given head-tail range.
-  // Requires `head` and `tail` values to be less than `capacity()`.
-  index_type entries(index_type head, index_type tail) const {
-    assert(head < capacity_ && tail < capacity_);
-    return tail - head + ((tail > head) ? 0 : capacity_);
-  }
-
-  // Returns the logical end position of entry `index`.
-  pos_type const& entry_end_pos(index_type index) const {
-    assert(IsValidIndex(index));
-    return Layout::Partial().Pointer<0>(data_)[index];
-  }
-
-  // Returns the child pointer of entry `index`.
-  CordRep* const& entry_child(index_type index) const {
-    assert(IsValidIndex(index));
-    return Layout::Partial(capacity()).Pointer<1>(data_)[index];
-  }
-
-  // Returns the data offset of entry `index`
-  offset_type const& entry_data_offset(index_type index) const {
-    assert(IsValidIndex(index));
-    return Layout::Partial(capacity(), capacity()).Pointer<2>(data_)[index];
-  }
-
-  // Appends the provided child node to the `rep` instance.
-  // Adopts a reference from `rep` and `child` which may not be null.
-  // If the provided child is a FLAT or EXTERNAL node, or a SUBSTRING node
-  // containing a FLAT or EXTERNAL node, then flat or external the node is added
-  // 'as is', with an offset added for the SUBSTRING case.
-  // If the provided child is a RING or CONCAT tree, or a SUBSTRING of a RING or
-  // CONCAT tree, then all child nodes not excluded by any start offset or
-  // length values are added recursively.
-  static CordRepRing* Append(CordRepRing* rep, CordRep* child);
-
-  // Appends the provided string data to the `rep` instance.
-  // This function will attempt to utilize any remaining capacity in the last
-  // node of the input if that node is not shared (directly or indirectly), and
-  // of type FLAT. Remaining data will be added as one or more FLAT nodes.
-  // Any last node added to the ring buffer will be allocated with up to
-  // `extra` bytes of capacity for (anticipated) subsequent append actions.
-  static CordRepRing* Append(CordRepRing* rep, string_view data,
-                             size_t extra = 0);
-
-  // Prepends the provided child node to the `rep` instance.
-  // Adopts a reference from `rep` and `child` which may not be null.
-  // If the provided child is a FLAT or EXTERNAL node, or a SUBSTRING node
-  // containing a FLAT or EXTERNAL node, then flat or external the node is
-  // prepended 'as is', with an optional offset added for the SUBSTRING case.
-  // If the provided child is a RING or CONCAT tree, or a SUBSTRING of a RING
-  // or CONCAT tree, then all child nodes not excluded by any start offset or
-  // length values are added recursively.
-  static CordRepRing* Prepend(CordRepRing* rep, CordRep* child);
-
-  // Prepends the provided string data to the `rep` instance.
-  // This function will attempt to utilize any remaining capacity in the first
-  // node of the input if that node is not shared (directly or indirectly), and
-  // of type FLAT. Remaining data will be added as one or more FLAT nodes.
-  // Any first node prepnded to the ring buffer will be allocated with up to
-  // `extra` bytes of capacity for (anticipated) subsequent prepend actions.
-  static CordRepRing* Prepend(CordRepRing* rep, string_view data,
-                              size_t extra = 0);
-
-  // Returns a span referencing potentially unused capacity in the last node.
-  // The returned span may be empty if no such capacity is available, or if the
-  // current instance is shared. Else, a span of size `n <= size` is returned.
-  // If non empty, the ring buffer is adjusted to the new length, with the newly
-  // added capacity left uninitialized. Callers should assign a value to the
-  // entire span before any other operations on this instance.
-  Span<char> GetAppendBuffer(size_t size);
-
-  // Returns a span referencing potentially unused capacity in the first node.
-  // This function is identical to GetAppendBuffer except that it returns a span
-  // referencing up to `size` capacity directly before the existing data.
-  Span<char> GetPrependBuffer(size_t size);
-
-  // Returns a cord ring buffer containing `len` bytes of data starting at
-  // `offset`. If the input is not shared, this function will remove all head
-  // and tail child nodes outside of the requested range, and adjust the new
-  // head and tail nodes as required. If the input is shared, this function
-  // returns a new instance sharing some or all of the nodes from the input.
-  static CordRepRing* SubRing(CordRepRing* r, size_t offset, size_t len,
-                              size_t extra = 0);
-
-  // Returns a cord ring buffer with the first `len` bytes removed.
-  // If the input is not shared, this function will remove all head child nodes
-  // fully inside the first `length` bytes, and adjust the new head as required.
-  // If the input is shared, this function returns a new instance sharing some
-  // or all of the nodes from the input.
-  static CordRepRing* RemoveSuffix(CordRepRing* r, size_t len,
-                                   size_t extra = 0);
-
-  // Returns a cord ring buffer with the last `len` bytes removed.
-  // If the input is not shared, this function will remove all head child nodes
-  // fully inside the first `length` bytes, and adjust the new head as required.
-  // If the input is shared, this function returns a new instance sharing some
-  // or all of the nodes from the input.
-  static CordRepRing* RemovePrefix(CordRepRing* r, size_t len,
-                                   size_t extra = 0);
-
-  // Returns the character at `offset`. Requires that `offset < length`.
-  char GetCharacter(size_t offset) const;
-
-  // Returns true if this instance manages a single contiguous buffer, in which
-  // case the (optional) output parameter `fragment` is set. Otherwise, the
-  // function returns false, and `fragment` is left unchanged.
-  bool IsFlat(absl::string_view* fragment) const;
-
-  // Returns true if the data starting at `offset` with length `len` is
-  // managed by this instance inside a single contiguous buffer, in which case
-  // the (optional) output parameter `fragment` is set to the contiguous memory
-  // starting at offset `offset` with length `length`. Otherwise, the function
-  // returns false, and `fragment` is left unchanged.
-  bool IsFlat(size_t offset, size_t len, absl::string_view* fragment) const;
-
-  // Testing only: set capacity to requested capacity.
-  void SetCapacityForTesting(size_t capacity);
-
-  // Returns the CordRep data pointer for the provided CordRep.
-  // Requires that the provided `rep` is either a FLAT or EXTERNAL CordRep.
-  static const char* GetLeafData(const CordRep* rep);
-
-  // Returns the CordRep data pointer for the provided CordRep.
-  // Requires that `rep` is either a FLAT, EXTERNAL, or SUBSTRING CordRep.
-  static const char* GetRepData(const CordRep* rep);
-
-  // Advances the provided position, wrapping around capacity as needed.
-  // Requires `index` < capacity()
-  inline index_type advance(index_type index) const;
-
-  // Advances the provided position by 'n`, wrapping around capacity as needed.
-  // Requires `index` < capacity() and `n` <= capacity.
-  inline index_type advance(index_type index, index_type n) const;
-
-  // Retreats the provided position, wrapping around 0 as needed.
-  // Requires `index` < capacity()
-  inline index_type retreat(index_type index) const;
-
-  // Retreats the provided position by 'n', wrapping around 0 as needed.
-  // Requires `index` < capacity()
-  inline index_type retreat(index_type index, index_type n) const;
-
-  // Returns the logical begin position of entry `index`
-  pos_type const& entry_begin_pos(index_type index) const {
-    return (index == head_) ? begin_pos_ : entry_end_pos(retreat(index));
-  }
-
-  // Returns the physical start offset of entry `index`
-  size_t entry_start_offset(index_type index) const {
-    return Distance(begin_pos_, entry_begin_pos(index));
-  }
-
-  // Returns the physical end offset of entry `index`
-  size_t entry_end_offset(index_type index) const {
-    return Distance(begin_pos_, entry_end_pos(index));
-  }
-
-  // Returns the data length for entry `index`
-  size_t entry_length(index_type index) const {
-    return Distance(entry_begin_pos(index), entry_end_pos(index));
-  }
-
-  // Returns the data for entry `index`
-  absl::string_view entry_data(index_type index) const;
-
-  // Returns the position for `offset` as {index, prefix}. `index` holds the
-  // index of the entry at the specified offset and `prefix` holds the relative
-  // offset inside that entry.
-  // Requires `offset` < length.
-  //
-  // For example we can implement GetCharacter(offset) as:
-  //   char GetCharacter(size_t offset) {
-  //     Position pos = this->Find(offset);
-  //     return this->entry_data(pos.pos)[pos.offset];
-  //   }
-  inline Position Find(size_t offset) const;
-
-  // Find starting at `head`
-  inline Position Find(index_type head, size_t offset) const;
-
-  // Returns the tail position for `offset` as {tail index, suffix}.
-  // `tail index` holds holds the index of the entry holding the offset directly
-  // before 'offset` advanced by one. 'suffix` holds the relative offset from
-  // that relative offset in the entry to the end of the entry.
-  // For example, FindTail(length) will return {tail(), 0}, FindTail(length - 5)
-  // will return {retreat(tail), 5)} provided the preceding entry contains at
-  // least 5 bytes of data.
-  // Requires offset >= 1 && offset <= length.
-  //
-  // This function is very useful in functions that need to clip the end of some
-  // ring buffer such as 'RemovePrefix'.
-  // For example, we could implement RemovePrefix for non shared instances as:
-  //   void RemoveSuffix(size_t n) {
-  //     Position pos = FindTail(length - n);
-  //     UnrefEntries(pos.pos, this->tail_);
-  //     this->tail_ = pos.pos;
-  //     entry(retreat(pos.pos)).end_pos -= pos.offset;
-  //   }
-  inline Position FindTail(size_t offset) const;
-
-  // Find tail starting at `head`
-  inline Position FindTail(index_type head, size_t offset) const;
-
-  // Invokes f(index_type index) for each entry inside the range [head, tail>
-  template <typename F>
-  void ForEach(index_type head, index_type tail, F&& f) const {
-    index_type n1 = (tail > head) ? tail : capacity_;
-    for (index_type i = head; i < n1; ++i) f(i);
-    if (tail <= head) {
-      for (index_type i = 0; i < tail; ++i) f(i);
-    }
-  }
-
-  // Invokes f(index_type index) for each entry inside this instance.
-  template <typename F>
-  void ForEach(F&& f) const {
-    ForEach(head_, tail_, std::forward<F>(f));
-  }
-
-  // Dump this instance's data tp stream `s` in human readable format, excluding
-  // the actual data content itself. Intended for debug purposes only.
-  friend std::ostream& operator<<(std::ostream& s, const CordRepRing& rep);
-
- private:
-  enum class AddMode { kAppend, kPrepend };
-
-  using Layout = container_internal::Layout<pos_type, CordRep*, offset_type>;
-
-  class Filler;
-  class Transaction;
-  class CreateTransaction;
-
-  static constexpr size_t kLayoutAlignment = Layout::Partial().Alignment();
-
-  // Creates a new CordRepRing.
-  explicit CordRepRing(index_type capacity) : capacity_(capacity) {}
-
-  // Returns true if `index` is a valid index into this instance.
-  bool IsValidIndex(index_type index) const;
-
-  // Debug use only: validates the provided CordRepRing invariants.
-  // Verification of all CordRepRing methods can be enabled by defining
-  // EXTRA_CORD_RING_VALIDATION, i.e.: `--copts=-DEXTRA_CORD_RING_VALIDATION`
-  // Verification is VERY expensive, so only do it for debugging purposes.
-  static CordRepRing* Validate(CordRepRing* rep, const char* file = nullptr,
-                               int line = 0);
-
-  // Allocates a CordRepRing large enough to hold `capacity + extra' entries.
-  // The returned capacity may be larger if the allocated memory allows for it.
-  // The maximum capacity of a CordRepRing is capped at kMaxCapacity.
-  // Throws `std::length_error` if `capacity + extra' exceeds kMaxCapacity.
-  static CordRepRing* New(size_t capacity, size_t extra);
-
-  // Deallocates (but does not destroy) the provided ring buffer.
-  static void Delete(CordRepRing* rep);
-
-  // Destroys the provided ring buffer, decrementing the reference count of all
-  // contained child CordReps. The provided 1\`rep` should have a ref count of
-  // one (pre decrement destroy call observing `refcount.IsOne()`) or zero
-  // (post decrement destroy call observing `!refcount.Decrement()`).
-  static void Destroy(CordRepRing* rep);
-
-  // Returns a mutable reference to the logical end position array.
-  pos_type* entry_end_pos() {
-    return Layout::Partial().Pointer<0>(data_);
-  }
-
-  // Returns a mutable reference to the child pointer array.
-  CordRep** entry_child() {
-    return Layout::Partial(capacity()).Pointer<1>(data_);
-  }
-
-  // Returns a mutable reference to the data offset array.
-  offset_type* entry_data_offset() {
-    return Layout::Partial(capacity(), capacity()).Pointer<2>(data_);
-  }
-
-  // Find implementations for the non fast path 0 / length cases.
-  Position FindSlow(index_type head, size_t offset) const;
-  Position FindTailSlow(index_type head, size_t offset) const;
-
-  // Finds the index of the first node that is inside a reasonable distance
-  // of the node at `offset` from which we can continue with a linear search.
-  template <bool wrap>
-  index_type FindBinary(index_type head, index_type tail, size_t offset) const;
-
-  // Fills the current (initialized) instance from the provided source, copying
-  // entries [head, tail). Adds a reference to copied entries if `ref` is true.
-  template <bool ref>
-  void Fill(const CordRepRing* src, index_type head, index_type tail);
-
-  // Create a copy of 'rep', copying all entries [head, tail), allocating room
-  // for `extra` entries. Adds a reference on all copied entries.
-  static CordRepRing* Copy(CordRepRing* rep, index_type head, index_type tail,
-                           size_t extra = 0);
-
-  // Returns a Mutable CordRepRing reference from `rep` with room for at least
-  // `extra` additional nodes. Adopts a reference count from `rep`.
-  // This function will return `rep` if, and only if:
-  // - rep.entries + extra <= rep.capacity
-  // - rep.refcount == 1
-  // Otherwise, this function will create a new copy of `rep` with additional
-  // capacity to satisfy `extra` extra nodes, and unref the old `rep` instance.
-  //
-  // If a new CordRepRing can not be allocated, or the new capacity would exceed
-  // the maximum capacity, then the input is consumed only, and an exception is
-  // thrown.
-  static CordRepRing* Mutable(CordRepRing* rep, size_t extra);
-
-  // Slow path for Append(CordRepRing* rep, CordRep* child). This function is
-  // exercised if the provided `child` in Append() is not a leaf node, i.e., a
-  // ring buffer or old (concat) cord tree.
-  static CordRepRing* AppendSlow(CordRepRing* rep, CordRep* child);
-
-  // Appends the provided leaf node. Requires `child` to be FLAT or EXTERNAL.
-  static CordRepRing* AppendLeaf(CordRepRing* rep, CordRep* child,
-                                 size_t offset, size_t length);
-
-  // Prepends the provided leaf node. Requires `child` to be FLAT or EXTERNAL.
-  static CordRepRing* PrependLeaf(CordRepRing* rep, CordRep* child,
-                                  size_t offset, size_t length);
-
-  // Slow path for Prepend(CordRepRing* rep, CordRep* child). This function is
-  // exercised if the provided `child` in Prepend() is not a leaf node, i.e., a
-  // ring buffer or old (concat) cord tree.
-  static CordRepRing* PrependSlow(CordRepRing* rep, CordRep* child);
-
-  // Slow path for Create(CordRep* child, size_t extra). This function is
-  // exercised if the provided `child` in Prepend() is not a leaf node, i.e., a
-  // ring buffer or old (concat) cord tree.
-  static CordRepRing* CreateSlow(CordRep* child, size_t extra);
-
-  // Creates a new ring buffer from the provided `child` leaf node. Requires
-  // `child` to be FLAT or EXTERNAL. on `rep`.
-  // The returned ring buffer has a capacity of at least `1 + extra`
-  static CordRepRing* CreateFromLeaf(CordRep* child, size_t offset,
-                                     size_t length, size_t extra);
-
-  // Appends or prepends (depending on AddMode) the ring buffer in `ring' to
-  // `rep` starting at `offset` with length `len`.
-  template <AddMode mode>
-  static CordRepRing* AddRing(CordRepRing* rep, CordRepRing* ring,
-                              size_t offset, size_t len);
-
-  // Increases the data offset for entry `index` by `n`.
-  void AddDataOffset(index_type index, size_t n);
-
-  // Decreases the length for entry `index` by `n`.
-  void SubLength(index_type index, size_t n);
-
-  index_type head_;
-  index_type tail_;
-  index_type capacity_;
-  pos_type begin_pos_;
-
-  alignas(kLayoutAlignment) char data_[kLayoutAlignment];
-
-  friend struct CordRep;
-};
-
-constexpr size_t CordRepRing::AllocSize(size_t capacity) {
-  return sizeof(CordRepRing) - sizeof(data_) +
-         Layout(capacity, capacity, capacity).AllocSize();
-}
-
-inline constexpr size_t CordRepRing::Distance(pos_type pos, pos_type end_pos) {
-  return (end_pos - pos);
-}
-
-inline const char* CordRepRing::GetLeafData(const CordRep* rep) {
-  return rep->tag != EXTERNAL ? rep->flat()->Data() : rep->external()->base;
-}
-
-inline const char* CordRepRing::GetRepData(const CordRep* rep) {
-  if (rep->tag >= FLAT) return rep->flat()->Data();
-  if (rep->tag == EXTERNAL) return rep->external()->base;
-  return GetLeafData(rep->substring()->child) + rep->substring()->start;
-}
-
-inline CordRepRing::index_type CordRepRing::advance(index_type index) const {
-  assert(index < capacity_);
-  return ++index == capacity_ ? 0 : index;
-}
-
-inline CordRepRing::index_type CordRepRing::advance(index_type index,
-                                                    index_type n) const {
-  assert(index < capacity_ && n <= capacity_);
-  return (index += n) >= capacity_ ? index - capacity_ : index;
-}
-
-inline CordRepRing::index_type CordRepRing::retreat(index_type index) const {
-  assert(index < capacity_);
-  return (index > 0 ? index : capacity_) - 1;
-}
-
-inline CordRepRing::index_type CordRepRing::retreat(index_type index,
-                                                    index_type n) const {
-  assert(index < capacity_ && n <= capacity_);
-  return index >= n ? index - n : capacity_ - n + index;
-}
-
-inline absl::string_view CordRepRing::entry_data(index_type index) const {
-  size_t data_offset = entry_data_offset(index);
-  return {GetRepData(entry_child(index)) + data_offset, entry_length(index)};
-}
-
-inline bool CordRepRing::IsValidIndex(index_type index) const {
-  if (index >= capacity_) return false;
-  return (tail_ > head_) ? (index >= head_ && index < tail_)
-                         : (index >= head_ || index < tail_);
-}
-
-#ifndef EXTRA_CORD_RING_VALIDATION
-inline CordRepRing* CordRepRing::Validate(CordRepRing* rep,
-                                          const char* /*file*/, int /*line*/) {
-  return rep;
-}
-#endif
-
-inline CordRepRing::Position CordRepRing::Find(size_t offset) const {
-  assert(offset < length);
-  return (offset == 0) ? Position{head_, 0} : FindSlow(head_, offset);
-}
-
-inline CordRepRing::Position CordRepRing::Find(index_type head,
-                                               size_t offset) const {
-  assert(offset < length);
-  assert(IsValidIndex(head) && offset >= entry_start_offset(head));
-  return (offset == 0) ? Position{head_, 0} : FindSlow(head, offset);
-}
-
-inline CordRepRing::Position CordRepRing::FindTail(size_t offset) const {
-  assert(offset > 0 && offset <= length);
-  return (offset == length) ? Position{tail_, 0} : FindTailSlow(head_, offset);
-}
-
-inline CordRepRing::Position CordRepRing::FindTail(index_type head,
-                                                   size_t offset) const {
-  assert(offset > 0 && offset <= length);
-  assert(IsValidIndex(head) && offset >= entry_start_offset(head) + 1);
-  return (offset == length) ? Position{tail_, 0} : FindTailSlow(head, offset);
-}
-
-// Now that CordRepRing is defined, we can define CordRep's helper casts:
-inline CordRepRing* CordRep::ring() {
-  assert(IsRing());
-  return static_cast<CordRepRing*>(this);
-}
-
-inline const CordRepRing* CordRep::ring() const {
-  assert(IsRing());
-  return static_cast<const CordRepRing*>(this);
-}
-
-inline bool CordRepRing::IsFlat(absl::string_view* fragment) const {
-  if (entries() == 1) {
-    if (fragment) *fragment = entry_data(head());
-    return true;
-  }
-  return false;
-}
-
-inline bool CordRepRing::IsFlat(size_t offset, size_t len,
-                                absl::string_view* fragment) const {
-  const Position pos = Find(offset);
-  const absl::string_view data = entry_data(pos.index);
-  if (data.length() >= len && data.length() - len >= pos.offset) {
-    if (fragment) *fragment = data.substr(pos.offset, len);
-    return true;
-  }
-  return false;
-}
-
-std::ostream& operator<<(std::ostream& s, const CordRepRing& rep);
-
-}  // namespace cord_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_STRINGS_INTERNAL_CORD_REP_RING_H_
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/cordz_info.cc b/contrib/restricted/abseil-cpp/absl/strings/internal/cordz_info.cc
index 515dfafbb3..b24c3da712 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/cordz_info.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/cordz_info.cc
@@ -21,7 +21,6 @@
 #include "absl/strings/internal/cord_internal.h"
 #include "absl/strings/internal/cord_rep_btree.h"
 #include "absl/strings/internal/cord_rep_crc.h"
-#include "absl/strings/internal/cord_rep_ring.h"
 #include "absl/strings/internal/cordz_handle.h"
 #include "absl/strings/internal/cordz_statistics.h"
 #include "absl/strings/internal/cordz_update_tracker.h"
@@ -33,8 +32,6 @@ namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace cord_internal {
 
-using ::absl::base_internal::SpinLockHolder;
-
 #ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
 constexpr size_t CordzInfo::kMaxStackDepth;
 #endif
@@ -79,6 +76,8 @@ class CordRepAnalyzer {
   // adds the results to `statistics`. Note that node counts and memory sizes
   // are not initialized, computed values are added to any existing values.
   void AnalyzeCordRep(const CordRep* rep) {
+    ABSL_ASSERT(rep != nullptr);
+
     // Process all linear nodes.
     // As per the class comments, use refcout - 1 on the top level node, as the
     // top level node is assumed to be referenced only for analysis purposes.
@@ -86,7 +85,7 @@ class CordRepAnalyzer {
     RepRef repref{rep, (refcount > 1) ? refcount - 1 : 1};
 
     // Process the top level CRC node, if present.
-    if (repref.rep->tag == CRC) {
+    if (repref.tag() == CRC) {
       statistics_.node_count++;
       statistics_.node_counts.crc++;
       memory_usage_.Add(sizeof(CordRepCrc), repref.refcount);
@@ -96,15 +95,14 @@ class CordRepAnalyzer {
     // Process all top level linear nodes (substrings and flats).
     repref = CountLinearReps(repref, memory_usage_);
 
-    if (repref.rep != nullptr) {
-      if (repref.rep->tag == RING) {
-        AnalyzeRing(repref);
-      } else if (repref.rep->tag == BTREE) {
+    switch (repref.tag()) {
+      case CordRepKind::BTREE:
         AnalyzeBtree(repref);
-      } else {
-        // We should have either a concat, btree, or ring node if not null.
-        assert(false);
-      }
+        break;
+      default:
+        // We should have a btree node if not null.
+        ABSL_ASSERT(repref.tag() == CordRepKind::UNUSED_0);
+        break;
     }
 
     // Adds values to output
@@ -122,11 +120,19 @@ class CordRepAnalyzer {
     const CordRep* rep;
     size_t refcount;
 
-    // Returns a 'child' RepRef which contains the cumulative reference count of
-    // this instance multiplied by the child's reference count.
+    // Returns a 'child' RepRef which contains the cumulative reference count
+    // of this instance multiplied by the child's reference count. Returns a
+    // nullptr RepRef value with a refcount of 0 if `child` is nullptr.
     RepRef Child(const CordRep* child) const {
+      if (child == nullptr) return RepRef{nullptr, 0};
       return RepRef{child, refcount * child->refcount.Get()};
     }
+
+    // Returns the tag of this rep, or UNUSED_0 if this instance is null
+    constexpr CordRepKind tag() const {
+      ABSL_ASSERT(rep == nullptr || rep->tag != CordRepKind::UNUSED_0);
+      return rep ? static_cast<CordRepKind>(rep->tag) : CordRepKind::UNUSED_0;
+    }
   };
 
   // Memory usage values
@@ -167,7 +173,7 @@ class CordRepAnalyzer {
   // buffers where we count children unrounded.
   RepRef CountLinearReps(RepRef rep, MemoryUsage& memory_usage) {
     // Consume all substrings
-    while (rep.rep->tag == SUBSTRING) {
+    while (rep.tag() == SUBSTRING) {
       statistics_.node_count++;
       statistics_.node_counts.substring++;
       memory_usage.Add(sizeof(CordRepSubstring), rep.refcount);
@@ -175,7 +181,7 @@ class CordRepAnalyzer {
     }
 
     // Consume possible FLAT
-    if (rep.rep->tag >= FLAT) {
+    if (rep.tag() >= FLAT) {
       size_t size = rep.rep->flat()->AllocatedSize();
       CountFlat(size);
       memory_usage.Add(size, rep.refcount);
@@ -183,7 +189,7 @@ class CordRepAnalyzer {
     }
 
     // Consume possible external
-    if (rep.rep->tag == EXTERNAL) {
+    if (rep.tag() == EXTERNAL) {
       statistics_.node_count++;
       statistics_.node_counts.external++;
       size_t size = rep.rep->length + sizeof(CordRepExternalImpl<intptr_t>);
@@ -194,17 +200,6 @@ class CordRepAnalyzer {
     return rep;
   }
 
-  // Analyzes the provided ring.
-  void AnalyzeRing(RepRef rep) {
-    statistics_.node_count++;
-    statistics_.node_counts.ring++;
-    const CordRepRing* ring = rep.rep->ring();
-    memory_usage_.Add(CordRepRing::AllocSize(ring->capacity()), rep.refcount);
-    ring->ForEach([&](CordRepRing::index_type pos) {
-      CountLinearReps(rep.Child(ring->entry_child(pos)), memory_usage_);
-    });
-  }
-
   // Analyzes the provided btree.
   void AnalyzeBtree(RepRef rep) {
     statistics_.node_count++;
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/memutil.cc b/contrib/restricted/abseil-cpp/absl/strings/internal/memutil.cc
index e2e7347c49..0bbd8aa1bd 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/memutil.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/memutil.cc
@@ -27,10 +27,18 @@ int memcasecmp(const char* s1, const char* s2, size_t len) {
   const unsigned char* us2 = reinterpret_cast<const unsigned char*>(s2);
 
   for (size_t i = 0; i < len; i++) {
-    const int diff =
-        int{static_cast<unsigned char>(absl::ascii_tolower(us1[i]))} -
-        int{static_cast<unsigned char>(absl::ascii_tolower(us2[i]))};
-    if (diff != 0) return diff;
+    unsigned char c1 = us1[i];
+    unsigned char c2 = us2[i];
+    // If bytes are the same, they will be the same when converted to lower.
+    // So we only need to convert if bytes are not equal.
+    // NOTE(b/308193381): We do not use `absl::ascii_tolower` here in order
+    // to avoid its lookup table and improve performance.
+    if (c1 != c2) {
+      c1 = c1 >= 'A' && c1 <= 'Z' ? c1 - 'A' + 'a' : c1;
+      c2 = c2 >= 'A' && c2 <= 'Z' ? c2 - 'A' + 'a' : c2;
+      const int diff = int{c1} - int{c2};
+      if (diff != 0) return diff;
+    }
   }
   return 0;
 }
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.cc b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.cc
index c0a9a28ef9..eeb2108154 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.cc
@@ -18,15 +18,28 @@
 //
 #include "absl/strings/internal/str_format/arg.h"
 
+#include <algorithm>
 #include <cassert>
-#include <cerrno>
+#include <cstddef>
+#include <cstdint>
 #include <cstdlib>
+#include <cstring>
+#include <cwchar>
 #include <string>
 #include <type_traits>
 
-#include "absl/base/port.h"
+#include "absl/base/config.h"
+#include "absl/base/optimization.h"
+#include "absl/container/fixed_array.h"
+#include "absl/numeric/int128.h"
+#include "absl/strings/internal/str_format/extension.h"
 #include "absl/strings/internal/str_format/float_conversion.h"
 #include "absl/strings/numbers.h"
+#include "absl/strings/string_view.h"
+
+#if defined(ABSL_HAVE_STD_STRING_VIEW)
+#include <string_view>
+#endif
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -298,6 +311,83 @@ inline bool ConvertStringArg(string_view v, const FormatConversionSpecImpl conv,
                                conv.has_left_flag());
 }
 
+struct ShiftState {
+  bool saw_high_surrogate = false;
+  uint8_t bits = 0;
+};
+
+// Converts `v` from UTF-16 or UTF-32 to UTF-8 and writes to `buf`. `buf` is
+// assumed to have enough space for the output. `s` is used to carry state
+// between successive calls with a UTF-16 surrogate pair. Returns the number of
+// chars written, or `static_cast<size_t>(-1)` on failure.
+//
+// This is basically std::wcrtomb(), but always outputting UTF-8 instead of
+// respecting the current locale.
+inline size_t WideToUtf8(wchar_t wc, char *buf, ShiftState &s) {
+  const auto v = static_cast<uint32_t>(wc);
+  if (v < 0x80) {
+    *buf = static_cast<char>(v);
+    return 1;
+  } else if (v < 0x800) {
+    *buf++ = static_cast<char>(0xc0 | (v >> 6));
+    *buf = static_cast<char>(0x80 | (v & 0x3f));
+    return 2;
+  } else if (v < 0xd800 || (v - 0xe000) < 0x2000) {
+    *buf++ = static_cast<char>(0xe0 | (v >> 12));
+    *buf++ = static_cast<char>(0x80 | ((v >> 6) & 0x3f));
+    *buf = static_cast<char>(0x80 | (v & 0x3f));
+    return 3;
+  } else if ((v - 0x10000) < 0x100000) {
+    *buf++ = static_cast<char>(0xf0 | (v >> 18));
+    *buf++ = static_cast<char>(0x80 | ((v >> 12) & 0x3f));
+    *buf++ = static_cast<char>(0x80 | ((v >> 6) & 0x3f));
+    *buf = static_cast<char>(0x80 | (v & 0x3f));
+    return 4;
+  } else if (v < 0xdc00) {
+    s.saw_high_surrogate = true;
+    s.bits = static_cast<uint8_t>(v & 0x3);
+    const uint8_t high_bits = ((v >> 6) & 0xf) + 1;
+    *buf++ = static_cast<char>(0xf0 | (high_bits >> 2));
+    *buf =
+        static_cast<char>(0x80 | static_cast<uint8_t>((high_bits & 0x3) << 4) |
+                          static_cast<uint8_t>((v >> 2) & 0xf));
+    return 2;
+  } else if (v < 0xe000 && s.saw_high_surrogate) {
+    *buf++ = static_cast<char>(0x80 | static_cast<uint8_t>(s.bits << 4) |
+                               static_cast<uint8_t>((v >> 6) & 0xf));
+    *buf = static_cast<char>(0x80 | (v & 0x3f));
+    s.saw_high_surrogate = false;
+    s.bits = 0;
+    return 2;
+  } else {
+    return static_cast<size_t>(-1);
+  }
+}
+
+inline bool ConvertStringArg(const wchar_t *v,
+                             size_t len,
+                             const FormatConversionSpecImpl conv,
+                             FormatSinkImpl *sink) {
+  FixedArray<char> mb(len * 4);
+  ShiftState s;
+  size_t chars_written = 0;
+  for (size_t i = 0; i < len; ++i) {
+    const size_t chars = WideToUtf8(v[i], &mb[chars_written], s);
+    if (chars == static_cast<size_t>(-1)) { return false; }
+    chars_written += chars;
+  }
+  return ConvertStringArg(string_view(mb.data(), chars_written), conv, sink);
+}
+
+bool ConvertWCharTImpl(wchar_t v, const FormatConversionSpecImpl conv,
+                       FormatSinkImpl *sink) {
+  char mb[4];
+  ShiftState s;
+  const size_t chars_written = WideToUtf8(v, mb, s);
+  return chars_written != static_cast<size_t>(-1) && !s.saw_high_surrogate &&
+         ConvertStringArg(string_view(mb, chars_written), conv, sink);
+}
+
 }  // namespace
 
 bool ConvertBoolArg(bool v, FormatSinkImpl *sink) {
@@ -316,11 +406,14 @@ bool ConvertIntArg(T v, FormatConversionSpecImpl conv, FormatSinkImpl *sink) {
 
   // This odd casting is due to a bug in -Wswitch behavior in gcc49 which causes
   // it to complain about a switch/case type mismatch, even though both are
-  // FormatConverionChar.  Likely this is because at this point
+  // FormatConversionChar.  Likely this is because at this point
   // FormatConversionChar is declared, but not defined.
   switch (static_cast<uint8_t>(conv.conversion_char())) {
     case static_cast<uint8_t>(FormatConversionCharInternal::c):
-      return ConvertCharImpl(static_cast<char>(v), conv, sink);
+      return (std::is_same<T, wchar_t>::value ||
+              (conv.length_mod() == LengthMod::l))
+                 ? ConvertWCharTImpl(static_cast<wchar_t>(v), conv, sink)
+                 : ConvertCharImpl(static_cast<char>(v), conv, sink);
 
     case static_cast<uint8_t>(FormatConversionCharInternal::o):
       as_digits.PrintAsOct(static_cast<U>(v));
@@ -372,6 +465,8 @@ template bool ConvertIntArg<signed char>(signed char v,
 template bool ConvertIntArg<unsigned char>(unsigned char v,
                                            FormatConversionSpecImpl conv,
                                            FormatSinkImpl *sink);
+template bool ConvertIntArg<wchar_t>(wchar_t v, FormatConversionSpecImpl conv,
+                                     FormatSinkImpl *sink);
 template bool ConvertIntArg<short>(short v,  // NOLINT
                                    FormatConversionSpecImpl conv,
                                    FormatSinkImpl *sink);
@@ -403,16 +498,29 @@ StringConvertResult FormatConvertImpl(const std::string &v,
   return {ConvertStringArg(v, conv, sink)};
 }
 
+StringConvertResult FormatConvertImpl(const std::wstring &v,
+                                      const FormatConversionSpecImpl conv,
+                                      FormatSinkImpl *sink) {
+  return {ConvertStringArg(v.data(), v.size(), conv, sink)};
+}
+
 StringConvertResult FormatConvertImpl(string_view v,
                                       const FormatConversionSpecImpl conv,
                                       FormatSinkImpl *sink) {
   return {ConvertStringArg(v, conv, sink)};
 }
 
-ArgConvertResult<FormatConversionCharSetUnion(
-    FormatConversionCharSetInternal::s, FormatConversionCharSetInternal::p)>
-FormatConvertImpl(const char *v, const FormatConversionSpecImpl conv,
-                  FormatSinkImpl *sink) {
+#if defined(ABSL_HAVE_STD_STRING_VIEW)
+StringConvertResult FormatConvertImpl(std::wstring_view v,
+                                      const FormatConversionSpecImpl conv,
+                                      FormatSinkImpl* sink) {
+  return {ConvertStringArg(v.data(), v.size(), conv, sink)};
+}
+#endif
+
+StringPtrConvertResult FormatConvertImpl(const char* v,
+                                         const FormatConversionSpecImpl conv,
+                                         FormatSinkImpl* sink) {
   if (conv.conversion_char() == FormatConversionCharInternal::p)
     return {FormatConvertImpl(VoidPtr(v), conv, sink).value};
   size_t len;
@@ -427,6 +535,30 @@ FormatConvertImpl(const char *v, const FormatConversionSpecImpl conv,
   return {ConvertStringArg(string_view(v, len), conv, sink)};
 }
 
+StringPtrConvertResult FormatConvertImpl(const wchar_t* v,
+                                         const FormatConversionSpecImpl conv,
+                                         FormatSinkImpl* sink) {
+  if (conv.conversion_char() == FormatConversionCharInternal::p) {
+    return {FormatConvertImpl(VoidPtr(v), conv, sink).value};
+  }
+  size_t len;
+  if (v == nullptr) {
+    len = 0;
+  } else if (conv.precision() < 0) {
+    len = std::wcslen(v);
+  } else {
+    // If precision is set, we look for the NUL-terminator on the valid range.
+    len = static_cast<size_t>(std::find(v, v + conv.precision(), L'\0') - v);
+  }
+  return {ConvertStringArg(v, len, conv, sink)};
+}
+
+StringPtrConvertResult FormatConvertImpl(std::nullptr_t,
+                                         const FormatConversionSpecImpl conv,
+                                         FormatSinkImpl* sink) {
+  return FormatConvertImpl(static_cast<const char*>(nullptr), conv, sink);
+}
+
 // ==================== Raw pointers ====================
 ArgConvertResult<FormatConversionCharSetInternal::p> FormatConvertImpl(
     VoidPtr v, const FormatConversionSpecImpl conv, FormatSinkImpl *sink) {
@@ -461,6 +593,11 @@ CharConvertResult FormatConvertImpl(char v, const FormatConversionSpecImpl conv,
                                     FormatSinkImpl *sink) {
   return {ConvertIntArg(v, conv, sink)};
 }
+CharConvertResult FormatConvertImpl(wchar_t v,
+                                    const FormatConversionSpecImpl conv,
+                                    FormatSinkImpl* sink) {
+  return {ConvertIntArg(v, conv, sink)};
+}
 
 // ==================== Ints ====================
 IntegralConvertResult FormatConvertImpl(signed char v,
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.h b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.h
index 3ce30feb49..309161d591 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/arg.h
@@ -19,8 +19,9 @@
 #include <wchar.h>
 
 #include <algorithm>
+#include <cstddef>
+#include <cstdint>
 #include <cstdio>
-#include <iomanip>
 #include <limits>
 #include <memory>
 #include <sstream>
@@ -28,13 +29,18 @@
 #include <type_traits>
 #include <utility>
 
-#include "absl/base/port.h"
+#include "absl/base/config.h"
+#include "absl/base/optimization.h"
 #include "absl/meta/type_traits.h"
 #include "absl/numeric/int128.h"
-#include "absl/strings/internal/has_absl_stringify.h"
+#include "absl/strings/has_absl_stringify.h"
 #include "absl/strings/internal/str_format/extension.h"
 #include "absl/strings/string_view.h"
 
+#if defined(ABSL_HAVE_STD_STRING_VIEW)
+#include <string_view>
+#endif
+
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
@@ -97,6 +103,9 @@ extern template bool ConvertIntArg<signed char>(signed char v,
 extern template bool ConvertIntArg<unsigned char>(unsigned char v,
                                                   FormatConversionSpecImpl conv,
                                                   FormatSinkImpl* sink);
+extern template bool ConvertIntArg<wchar_t>(wchar_t v,
+                                            FormatConversionSpecImpl conv,
+                                            FormatSinkImpl* sink);
 extern template bool ConvertIntArg<short>(short v,  // NOLINT
                                           FormatConversionSpecImpl conv,
                                           FormatSinkImpl* sink);
@@ -158,6 +167,7 @@ template <typename T>
 auto FormatConvertImpl(const T& v, FormatConversionSpecImpl,
                        FormatSinkImpl* sink)
     -> std::enable_if_t<!std::is_enum<T>::value &&
+                            !std::is_same<T, absl::Cord>::value &&
                             std::is_void<decltype(AbslStringify(
                                 std::declval<FormatSink&>(), v))>::value,
                         ArgConvertResult<FormatConversionCharSetInternal::v>> {
@@ -202,30 +212,49 @@ constexpr FormatConversionCharSet ExtractCharSet(ArgConvertResult<C>) {
   return C;
 }
 
-using StringConvertResult = ArgConvertResult<FormatConversionCharSetUnion(
-    FormatConversionCharSetInternal::s, FormatConversionCharSetInternal::v)>;
 ArgConvertResult<FormatConversionCharSetInternal::p> FormatConvertImpl(
     VoidPtr v, FormatConversionSpecImpl conv, FormatSinkImpl* sink);
 
 // Strings.
+using StringConvertResult = ArgConvertResult<FormatConversionCharSetUnion(
+    FormatConversionCharSetInternal::s,
+    FormatConversionCharSetInternal::v)>;
 StringConvertResult FormatConvertImpl(const std::string& v,
                                       FormatConversionSpecImpl conv,
                                       FormatSinkImpl* sink);
+StringConvertResult FormatConvertImpl(const std::wstring& v,
+                                      FormatConversionSpecImpl conv,
+                                      FormatSinkImpl* sink);
 StringConvertResult FormatConvertImpl(string_view v,
                                       FormatConversionSpecImpl conv,
                                       FormatSinkImpl* sink);
-#if defined(ABSL_HAVE_STD_STRING_VIEW) && !defined(ABSL_USES_STD_STRING_VIEW)
+#if defined(ABSL_HAVE_STD_STRING_VIEW)
+StringConvertResult FormatConvertImpl(std::wstring_view v,
+                                      FormatConversionSpecImpl conv,
+                                      FormatSinkImpl* sink);
+#if !defined(ABSL_USES_STD_STRING_VIEW)
 inline StringConvertResult FormatConvertImpl(std::string_view v,
                                              FormatConversionSpecImpl conv,
                                              FormatSinkImpl* sink) {
   return FormatConvertImpl(absl::string_view(v.data(), v.size()), conv, sink);
 }
-#endif  // ABSL_HAVE_STD_STRING_VIEW && !ABSL_USES_STD_STRING_VIEW
-
-ArgConvertResult<FormatConversionCharSetUnion(
-    FormatConversionCharSetInternal::s, FormatConversionCharSetInternal::p)>
-FormatConvertImpl(const char* v, const FormatConversionSpecImpl conv,
-                  FormatSinkImpl* sink);
+#endif  // !ABSL_USES_STD_STRING_VIEW
+#endif  // ABSL_HAVE_STD_STRING_VIEW
+
+using StringPtrConvertResult = ArgConvertResult<FormatConversionCharSetUnion(
+    FormatConversionCharSetInternal::s,
+    FormatConversionCharSetInternal::p)>;
+StringPtrConvertResult FormatConvertImpl(const char* v,
+                                         FormatConversionSpecImpl conv,
+                                         FormatSinkImpl* sink);
+StringPtrConvertResult FormatConvertImpl(const wchar_t* v,
+                                         FormatConversionSpecImpl conv,
+                                         FormatSinkImpl* sink);
+// This overload is needed to disambiguate, since `nullptr` could match either
+// of the other overloads equally well.
+StringPtrConvertResult FormatConvertImpl(std::nullptr_t,
+                                         FormatConversionSpecImpl conv,
+                                         FormatSinkImpl* sink);
 
 template <class AbslCord, typename std::enable_if<std::is_same<
                               AbslCord, absl::Cord>::value>::type* = nullptr>
@@ -279,6 +308,9 @@ FloatingConvertResult FormatConvertImpl(long double v,
 // Chars.
 CharConvertResult FormatConvertImpl(char v, FormatConversionSpecImpl conv,
                                     FormatSinkImpl* sink);
+CharConvertResult FormatConvertImpl(wchar_t v,
+                                    FormatConversionSpecImpl conv,
+                                    FormatSinkImpl* sink);
 
 // Ints.
 IntegralConvertResult FormatConvertImpl(signed char v,
@@ -333,7 +365,7 @@ IntegralConvertResult FormatConvertImpl(T v, FormatConversionSpecImpl conv,
 template <typename T>
 typename std::enable_if<std::is_enum<T>::value &&
                             !HasUserDefinedConvert<T>::value &&
-                            !strings_internal::HasAbslStringify<T>::value,
+                            !HasAbslStringify<T>::value,
                         IntegralConvertResult>::type
 FormatConvertImpl(T v, FormatConversionSpecImpl conv, FormatSinkImpl* sink);
 
@@ -440,6 +472,7 @@ class FormatArgImpl {
   // Anything with a user-defined Convert will get its own vtable.
   // For everything else:
   //   - Decay char* and char arrays into `const char*`
+  //   - Decay wchar_t* and wchar_t arrays into `const wchar_t*`
   //   - Decay any other pointer to `const void*`
   //   - Decay all enums to the integral promotion of their underlying type.
   //   - Decay function pointers to void*.
@@ -447,20 +480,23 @@ class FormatArgImpl {
   struct DecayType {
     static constexpr bool kHasUserDefined =
         str_format_internal::HasUserDefinedConvert<T>::value ||
-        strings_internal::HasAbslStringify<T>::value;
+        HasAbslStringify<T>::value;
     using type = typename std::conditional<
         !kHasUserDefined && std::is_convertible<T, const char*>::value,
         const char*,
-        typename std::conditional<!kHasUserDefined &&
-                                      std::is_convertible<T, VoidPtr>::value,
-                                  VoidPtr, const T&>::type>::type;
+        typename std::conditional<
+            !kHasUserDefined && std::is_convertible<T, const wchar_t*>::value,
+            const wchar_t*,
+            typename std::conditional<
+                !kHasUserDefined && std::is_convertible<T, VoidPtr>::value,
+                VoidPtr,
+                const T&>::type>::type>::type;
   };
   template <typename T>
-  struct DecayType<T,
-                   typename std::enable_if<
-                       !str_format_internal::HasUserDefinedConvert<T>::value &&
-                       !strings_internal::HasAbslStringify<T>::value &&
-                       std::is_enum<T>::value>::type> {
+  struct DecayType<
+      T, typename std::enable_if<
+             !str_format_internal::HasUserDefinedConvert<T>::value &&
+             !HasAbslStringify<T>::value && std::is_enum<T>::value>::type> {
     using type = decltype(+typename std::underlying_type<T>::type());
   };
 
@@ -585,7 +621,7 @@ class FormatArgImpl {
   E template bool FormatArgImpl::Dispatch<T>(Data, FormatConversionSpecImpl, \
                                              void*)
 
-#define ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_(...)                   \
+#define ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_NO_WSTRING_VIEW_(...)   \
   ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(str_format_internal::VoidPtr,     \
                                              __VA_ARGS__);                     \
   ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(bool, __VA_ARGS__);               \
@@ -611,7 +647,19 @@ class FormatArgImpl {
   ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(long double, __VA_ARGS__);        \
   ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(const char*, __VA_ARGS__);        \
   ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(std::string, __VA_ARGS__);        \
-  ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(string_view, __VA_ARGS__)
+  ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(string_view, __VA_ARGS__);        \
+  ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(const wchar_t*, __VA_ARGS__);     \
+  ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(std::wstring, __VA_ARGS__)
+
+#if defined(ABSL_HAVE_STD_STRING_VIEW)
+#define ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_(...)       \
+  ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_NO_WSTRING_VIEW_( \
+      __VA_ARGS__);                                                \
+  ABSL_INTERNAL_FORMAT_DISPATCH_INSTANTIATE_(std::wstring_view, __VA_ARGS__)
+#else
+#define ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_(...) \
+  ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_NO_WSTRING_VIEW_(__VA_ARGS__)
+#endif
 
 ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_(extern);
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.cc b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.cc
index 77a4222337..87e23b565c 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.cc
@@ -14,10 +14,24 @@
 
 #include "absl/strings/internal/str_format/bind.h"
 
+#include <algorithm>
+#include <cassert>
 #include <cerrno>
+#include <cstddef>
+#include <cstdio>
+#include <ios>
 #include <limits>
+#include <ostream>
 #include <sstream>
 #include <string>
+#include "absl/base/config.h"
+#include "absl/base/optimization.h"
+#include "absl/strings/internal/str_format/arg.h"
+#include "absl/strings/internal/str_format/constexpr_parser.h"
+#include "absl/strings/internal/str_format/extension.h"
+#include "absl/strings/internal/str_format/output.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/span.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -90,6 +104,8 @@ inline bool ArgContext::Bind(const UnboundConversion* unbound,
     } else {
       FormatConversionSpecImplFriend::SetFlags(unbound->flags, bound);
     }
+
+    FormatConversionSpecImplFriend::SetLengthMod(unbound->length_mod, bound);
   } else {
     FormatConversionSpecImplFriend::SetFlags(unbound->flags, bound);
     FormatConversionSpecImplFriend::SetWidth(-1, bound);
@@ -215,7 +231,7 @@ std::string& AppendPack(std::string* out, const UntypedFormatSpecImpl format,
   return *out;
 }
 
-std::string FormatPack(const UntypedFormatSpecImpl format,
+std::string FormatPack(UntypedFormatSpecImpl format,
                        absl::Span<const FormatArgImpl> args) {
   std::string out;
   if (ABSL_PREDICT_FALSE(!FormatUntyped(&out, format, args))) {
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.h b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.h
index 5e2a43d5c9..120bc355c7 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/bind.h
@@ -15,16 +15,19 @@
 #ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_BIND_H_
 #define ABSL_STRINGS_INTERNAL_STR_FORMAT_BIND_H_
 
-#include <array>
+#include <cassert>
 #include <cstdio>
-#include <sstream>
+#include <ostream>
 #include <string>
 
-#include "absl/base/port.h"
+#include "absl/base/config.h"
 #include "absl/container/inlined_vector.h"
 #include "absl/strings/internal/str_format/arg.h"
 #include "absl/strings/internal/str_format/checker.h"
+#include "absl/strings/internal/str_format/constexpr_parser.h"
+#include "absl/strings/internal/str_format/extension.h"
 #include "absl/strings/internal/str_format/parser.h"
+#include "absl/strings/string_view.h"
 #include "absl/types/span.h"
 #include "absl/utility/utility.h"
 
@@ -203,7 +206,7 @@ bool FormatUntyped(FormatRawSinkImpl raw_sink, UntypedFormatSpecImpl format,
 std::string& AppendPack(std::string* out, UntypedFormatSpecImpl format,
                         absl::Span<const FormatArgImpl> args);
 
-std::string FormatPack(const UntypedFormatSpecImpl format,
+std::string FormatPack(UntypedFormatSpecImpl format,
                        absl::Span<const FormatArgImpl> args);
 
 int FprintF(std::FILE* output, UntypedFormatSpecImpl format,
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/constexpr_parser.h b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/constexpr_parser.h
index b70a16e40c..8f59387047 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/constexpr_parser.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/constexpr_parser.h
@@ -17,17 +17,18 @@
 
 #include <cassert>
 #include <cstdint>
+#include <cstdio>
 #include <limits>
 
+#include "absl/base/config.h"
 #include "absl/base/const_init.h"
+#include "absl/base/optimization.h"
 #include "absl/strings/internal/str_format/extension.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
-enum class LengthMod : std::uint8_t { h, hh, l, ll, L, j, z, t, q, none };
-
 // The analyzed properties of a single specified conversion.
 struct UnboundConversion {
   // This is a user defined default constructor on purpose to skip the
@@ -306,7 +307,6 @@ constexpr const char* ConsumeConversion(const char* pos, const char* const end,
     if (ABSL_PREDICT_FALSE(!tag.is_length())) return nullptr;
 
     // It is a length modifier.
-    using str_format_internal::LengthMod;
     LengthMod length_mod = tag.as_length();
     ABSL_FORMAT_PARSER_INTERNAL_GET_CHAR();
     if (c == 'h' && length_mod == LengthMod::h) {
@@ -322,6 +322,11 @@ constexpr const char* ConsumeConversion(const char* pos, const char* const end,
 
     if (ABSL_PREDICT_FALSE(c == 'v')) return nullptr;
     if (ABSL_PREDICT_FALSE(!tag.is_conv())) return nullptr;
+
+    // `wchar_t` args are marked non-basic so `Bind()` will copy the length mod.
+    if (conv->length_mod == LengthMod::l && c == 'c') {
+      conv->flags = conv->flags | Flags::kNonBasic;
+    }
   }
 #undef ABSL_FORMAT_PARSER_INTERNAL_GET_CHAR
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/extension.h b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/extension.h
index 8de42d2cfc..173284c6c7 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/extension.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/extension.h
@@ -16,16 +16,14 @@
 #ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_EXTENSION_H_
 #define ABSL_STRINGS_INTERNAL_STR_FORMAT_EXTENSION_H_
 
-#include <limits.h>
 
 #include <cstddef>
 #include <cstdint>
 #include <cstring>
 #include <ostream>
+#include <string>
 
 #include "absl/base/config.h"
-#include "absl/base/port.h"
-#include "absl/meta/type_traits.h"
 #include "absl/strings/internal/str_format/output.h"
 #include "absl/strings/string_view.h"
 
@@ -34,6 +32,7 @@ ABSL_NAMESPACE_BEGIN
 
 enum class FormatConversionChar : uint8_t;
 enum class FormatConversionCharSet : uint64_t;
+enum class LengthMod : std::uint8_t { h, hh, l, ll, L, j, z, t, q, none };
 
 namespace str_format_internal {
 
@@ -139,7 +138,8 @@ enum class Flags : uint8_t {
   kAlt = 1 << 3,
   kZero = 1 << 4,
   // This is not a real flag. It just exists to turn off kBasic when no other
-  // flags are set. This is for when width/precision are specified.
+  // flags are set. This is for when width/precision are specified, or a length
+  // modifier affects the behavior ("%lc").
   kNonBasic = 1 << 5,
 };
 
@@ -285,6 +285,8 @@ class FormatConversionSpecImpl {
   bool has_alt_flag() const { return FlagsContains(flags_, Flags::kAlt); }
   bool has_zero_flag() const { return FlagsContains(flags_, Flags::kZero); }
 
+  LengthMod length_mod() const { return length_mod_; }
+
   FormatConversionChar conversion_char() const {
     // Keep this field first in the struct . It generates better code when
     // accessing it when ConversionSpec is passed by value in registers.
@@ -310,6 +312,7 @@ class FormatConversionSpecImpl {
   friend struct str_format_internal::FormatConversionSpecImplFriend;
   FormatConversionChar conv_ = FormatConversionCharInternal::kNone;
   Flags flags_;
+  LengthMod length_mod_ = LengthMod::none;
   int width_;
   int precision_;
 };
@@ -318,6 +321,9 @@ struct FormatConversionSpecImplFriend final {
   static void SetFlags(Flags f, FormatConversionSpecImpl* conv) {
     conv->flags_ = f;
   }
+  static void SetLengthMod(LengthMod l, FormatConversionSpecImpl* conv) {
+    conv->length_mod_ = l;
+  }
   static void SetConversionChar(FormatConversionChar c,
                                 FormatConversionSpecImpl* conv) {
     conv->conv_ = c;
diff --git a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/parser.h b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/parser.h
index 35b6d49c14..b1d6d5fd0e 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/parser.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/internal/str_format/parser.h
@@ -15,22 +15,23 @@
 #ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_PARSER_H_
 #define ABSL_STRINGS_INTERNAL_STR_FORMAT_PARSER_H_
 
-#include <limits.h>
 #include <stddef.h>
 #include <stdlib.h>
 
 #include <cassert>
-#include <cstdint>
+#include <cstring>
 #include <initializer_list>
-#include <iosfwd>
-#include <iterator>
 #include <memory>
 #include <string>
+#include <utility>
 #include <vector>
 
+#include "absl/base/config.h"
+#include "absl/base/optimization.h"
 #include "absl/strings/internal/str_format/checker.h"
 #include "absl/strings/internal/str_format/constexpr_parser.h"
 #include "absl/strings/internal/str_format/extension.h"
+#include "absl/strings/string_view.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
diff --git a/contrib/restricted/abseil-cpp/absl/strings/match.cc b/contrib/restricted/abseil-cpp/absl/strings/match.cc
index 3b81b2c052..72ae6a430a 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/match.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/match.cc
@@ -17,10 +17,13 @@
 #include <algorithm>
 #include <cstdint>
 
+#include "absl/base/config.h"
 #include "absl/base/internal/endian.h"
+#include "absl/base/optimization.h"
 #include "absl/numeric/bits.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/internal/memutil.h"
+#include "absl/strings/string_view.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
diff --git a/contrib/restricted/abseil-cpp/absl/strings/numbers.cc b/contrib/restricted/abseil-cpp/absl/strings/numbers.cc
index c43c6bcc19..882c3a8b85 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/numbers.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/numbers.cc
@@ -20,32 +20,36 @@
 #include <algorithm>
 #include <cassert>
 #include <cfloat>  // for DBL_DIG and FLT_DIG
+#include <climits>
 #include <cmath>   // for HUGE_VAL
+#include <cstddef>
 #include <cstdint>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <iterator>
 #include <limits>
-#include <memory>
+#include <system_error>  // NOLINT(build/c++11)
+#include <type_traits>
 #include <utility>
 
 #include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/endian.h"
 #include "absl/base/internal/raw_logging.h"
+#include "absl/base/nullability.h"
 #include "absl/base/optimization.h"
 #include "absl/numeric/bits.h"
+#include "absl/numeric/int128.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/charconv.h"
-#include "absl/strings/escaping.h"
-#include "absl/strings/internal/memutil.h"
 #include "absl/strings/match.h"
-#include "absl/strings/str_cat.h"
+#include "absl/strings/string_view.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
-bool SimpleAtof(absl::string_view str, float* out) {
+bool SimpleAtof(absl::string_view str, absl::Nonnull<float*> out) {
   *out = 0.0;
   str = StripAsciiWhitespace(str);
   // std::from_chars doesn't accept an initial +, but SimpleAtof does, so if one
@@ -76,7 +80,7 @@ bool SimpleAtof(absl::string_view str, float* out) {
   return true;
 }
 
-bool SimpleAtod(absl::string_view str, double* out) {
+bool SimpleAtod(absl::string_view str, absl::Nonnull<double*> out) {
   *out = 0.0;
   str = StripAsciiWhitespace(str);
   // std::from_chars doesn't accept an initial +, but SimpleAtod does, so if one
@@ -107,7 +111,7 @@ bool SimpleAtod(absl::string_view str, double* out) {
   return true;
 }
 
-bool SimpleAtob(absl::string_view str, bool* out) {
+bool SimpleAtob(absl::string_view str, absl::Nonnull<bool*> out) {
   ABSL_RAW_CHECK(out != nullptr, "Output pointer must not be nullptr.");
   if (EqualsIgnoreCase(str, "true") || EqualsIgnoreCase(str, "t") ||
       EqualsIgnoreCase(str, "yes") || EqualsIgnoreCase(str, "y") ||
@@ -155,29 +159,71 @@ constexpr uint32_t kTwoZeroBytes = 0x0101 * '0';
 constexpr uint64_t kFourZeroBytes = 0x01010101 * '0';
 constexpr uint64_t kEightZeroBytes = 0x0101010101010101ull * '0';
 
-// * 103 / 1024 is a division by 10 for values from 0 to 99. It's also a
-// division of a structure [k takes 2 bytes][m takes 2 bytes], then * 103 / 1024
-// will be [k / 10][m / 10]. It allows parallel division.
-constexpr uint64_t kDivisionBy10Mul = 103u;
+template <typename T>
+constexpr T Pow(T base, uint32_t n) {
+  // Exponentiation by squaring
+  return static_cast<T>((n > 1 ? Pow(base * base, n >> 1) : static_cast<T>(1)) *
+                        ((n & 1) ? base : static_cast<T>(1)));
+}
+
+// Given n, calculates C where the following holds for all 0 <= x < Pow(100, n):
+// x / Pow(10, n) == x * C / Pow(2, n * 10)
+// In other words, it allows us to divide by a power of 10 via a single
+// multiplication and bit shifts, assuming the input will be smaller than the
+// square of that power of 10.
+template <typename T>
+constexpr T ComputePowerOf100DivisionCoefficient(uint32_t n) {
+  if (n > 4) {
+    // This doesn't work for large powers of 100, due to overflow
+    abort();
+  }
+  T denom = 16 - 1;
+  T num = (denom + 1) - 10;
+  T gcd = 3;  // Greatest common divisor of numerator and denominator
+  denom = Pow(denom / gcd, n);
+  num = Pow(num / gcd, 9 * n);
+  T quotient = num / denom;
+  if (num % denom >= denom / 2) {
+    // Round up, since the remainder is more than half the denominator
+    ++quotient;
+  }
+  return quotient;
+}
+
+// * kDivisionBy10Mul / kDivisionBy10Div is a division by 10 for values from 0
+// to 99. It's also a division of a structure [k takes 2 bytes][m takes 2
+// bytes], then * kDivisionBy10Mul / kDivisionBy10Div will be [k / 10][m / 10].
+// It allows parallel division.
+constexpr uint64_t kDivisionBy10Mul =
+    ComputePowerOf100DivisionCoefficient<uint64_t>(1);
+static_assert(kDivisionBy10Mul == 103,
+              "division coefficient for 10 is incorrect");
 constexpr uint64_t kDivisionBy10Div = 1 << 10;
 
-// * 10486 / 1048576 is a division by 100 for values from 0 to 9999.
-constexpr uint64_t kDivisionBy100Mul = 10486u;
+// * kDivisionBy100Mul / kDivisionBy100Div is a division by 100 for values from
+// 0 to 9999.
+constexpr uint64_t kDivisionBy100Mul =
+    ComputePowerOf100DivisionCoefficient<uint64_t>(2);
+static_assert(kDivisionBy100Mul == 10486,
+              "division coefficient for 100 is incorrect");
 constexpr uint64_t kDivisionBy100Div = 1 << 20;
 
-// Encode functions write the ASCII output of input `n` to `out_str`.
-inline char* EncodeHundred(uint32_t n, char* out_str) {
-  int num_digits = static_cast<int>(n - 10) >> 8;
-  uint32_t base = kTwoZeroBytes;
-  uint32_t div10 = (n * kDivisionBy10Mul) / kDivisionBy10Div;
-  uint32_t mod10 = n - 10u * div10;
-  base += div10 + (mod10 << 8);
-  base >>= num_digits & 8;
-  little_endian::Store16(out_str, static_cast<uint16_t>(base));
-  return out_str + 2 + num_digits;
+static_assert(ComputePowerOf100DivisionCoefficient<uint64_t>(3) == 1073742,
+              "division coefficient for 1000 is incorrect");
+
+// Same as `PrepareEightDigits`, but produces 2 digits for integers < 100.
+inline uint32_t PrepareTwoDigitsImpl(uint32_t i, bool reversed) {
+  assert(i < 100);
+  uint32_t div10 = (i * kDivisionBy10Mul) / kDivisionBy10Div;
+  uint32_t mod10 = i - 10u * div10;
+  return (div10 << (reversed ? 8 : 0)) + (mod10 << (reversed ? 0 : 8));
+}
+inline uint32_t PrepareTwoDigits(uint32_t i) {
+  return PrepareTwoDigitsImpl(i, false);
 }
 
-inline char* EncodeTenThousand(uint32_t n, char* out_str) {
+// Same as `PrepareEightDigits`, but produces 4 digits for integers < 10000.
+inline uint32_t PrepareFourDigitsImpl(uint32_t n, bool reversed) {
   // We split lower 2 digits and upper 2 digits of n into 2 byte consecutive
   // blocks. 123 ->  [\0\1][\0\23]. We divide by 10 both blocks
   // (it's 1 division + zeroing upper bits), and compute modulo 10 as well "in
@@ -185,146 +231,335 @@ inline char* EncodeTenThousand(uint32_t n, char* out_str) {
   // strip trailing zeros, add ASCII '0000' and return.
   uint32_t div100 = (n * kDivisionBy100Mul) / kDivisionBy100Div;
   uint32_t mod100 = n - 100ull * div100;
-  uint32_t hundreds = (mod100 << 16) + div100;
+  uint32_t hundreds =
+      (mod100 << (reversed ? 0 : 16)) + (div100 << (reversed ? 16 : 0));
   uint32_t tens = (hundreds * kDivisionBy10Mul) / kDivisionBy10Div;
   tens &= (0xFull << 16) | 0xFull;
-  tens += (hundreds - 10ull * tens) << 8;
-  ABSL_ASSUME(tens != 0);
-  // The result can contain trailing zero bits, we need to strip them to a first
-  // significant byte in a final representation. For example, for n = 123, we
-  // have tens to have representation \0\1\2\3. We do `& -8` to round
-  // to a multiple to 8 to strip zero bytes, not all zero bits.
-  // countr_zero to help.
-  // 0 minus 8 to make MSVC happy.
-  uint32_t zeroes = static_cast<uint32_t>(absl::countr_zero(tens)) & (0 - 8ull);
-  tens += kFourZeroBytes;
-  tens >>= zeroes;
-  little_endian::Store32(out_str, tens);
-  return out_str + sizeof(tens) - zeroes / 8;
+  tens = (tens << (reversed ? 8 : 0)) +
+         static_cast<uint32_t>((hundreds - 10ull * tens) << (reversed ? 0 : 8));
+  return tens;
+}
+inline uint32_t PrepareFourDigits(uint32_t n) {
+  return PrepareFourDigitsImpl(n, false);
+}
+inline uint32_t PrepareFourDigitsReversed(uint32_t n) {
+  return PrepareFourDigitsImpl(n, true);
 }
 
-// Prepare functions return an integer that should be written to out_str
-// (but possibly include trailing zeros).
-// For hi < 10000, lo < 10000 returns uint64_t as encoded in ASCII with
-// possibly trailing zeroes of the number hi * 10000 + lo.
-inline uint64_t PrepareTenThousands(uint64_t hi, uint64_t lo) {
-  uint64_t merged = hi | (lo << 32);
+// Helper function to produce an ASCII representation of `i`.
+//
+// Function returns an 8-byte integer which when summed with `kEightZeroBytes`,
+// can be treated as a printable buffer with ascii representation of `i`,
+// possibly with leading zeros.
+//
+// Example:
+//
+//  uint64_t buffer = PrepareEightDigits(102030) + kEightZeroBytes;
+//  char* ascii = reinterpret_cast<char*>(&buffer);
+//  // Note two leading zeros:
+//  EXPECT_EQ(absl::string_view(ascii, 8), "00102030");
+//
+// If `Reversed` is set to true, the result becomes reversed to "03020100".
+//
+// Pre-condition: `i` must be less than 100000000.
+inline uint64_t PrepareEightDigitsImpl(uint32_t i, bool reversed) {
+  ABSL_ASSUME(i < 10000'0000);
+  // Prepare 2 blocks of 4 digits "in parallel".
+  uint32_t hi = i / 10000;
+  uint32_t lo = i % 10000;
+  uint64_t merged = (uint64_t{hi} << (reversed ? 32 : 0)) |
+                    (uint64_t{lo} << (reversed ? 0 : 32));
   uint64_t div100 = ((merged * kDivisionBy100Mul) / kDivisionBy100Div) &
                     ((0x7Full << 32) | 0x7Full);
   uint64_t mod100 = merged - 100ull * div100;
-  uint64_t hundreds = (mod100 << 16) + div100;
+  uint64_t hundreds =
+      (mod100 << (reversed ? 0 : 16)) + (div100 << (reversed ? 16 : 0));
   uint64_t tens = (hundreds * kDivisionBy10Mul) / kDivisionBy10Div;
   tens &= (0xFull << 48) | (0xFull << 32) | (0xFull << 16) | 0xFull;
-  tens += (hundreds - 10ull * tens) << 8;
+  tens = (tens << (reversed ? 8 : 0)) +
+         ((hundreds - 10ull * tens) << (reversed ? 0 : 8));
   return tens;
 }
+inline uint64_t PrepareEightDigits(uint32_t i) {
+  return PrepareEightDigitsImpl(i, false);
+}
+inline uint64_t PrepareEightDigitsReversed(uint32_t i) {
+  return PrepareEightDigitsImpl(i, true);
+}
+
+template <typename T, typename BackwardIt>
+class FastUIntToStringConverter {
+  static_assert(
+      std::is_same<T, decltype(+std::declval<T>())>::value,
+      "to avoid code bloat, only instantiate this for int and larger types");
+  static_assert(std::is_unsigned<T>::value,
+                "this class is only for unsigned types");
+
+ public:
+  // Outputs the given number backward (like with std::copy_backward),
+  // starting from the end of the string.
+  // The number of digits in the number must have been already measured and
+  // passed *exactly*, otherwise the behavior is undefined.
+  // (This is an optimization, as calculating the number of digits again would
+  // slow down the hot path.)
+  // Returns an iterator to the start of the suffix that was appended.
+  static BackwardIt FastIntToBufferBackward(T v, BackwardIt end) {
+    // THIS IS A HOT FUNCTION with a very deliberate structure to exploit branch
+    // prediction and shorten the critical path for smaller numbers.
+    // Do not move around the if/else blocks or attempt to simplify it
+    // without benchmarking any changes.
+
+    if (v < 10) {
+      goto AT_LEAST_1 /* NOTE: mandatory for the 0 case */;
+    }
+    if (v < 1000) {
+      goto AT_LEAST_10;
+    }
+    if (v < 10000000) {
+      goto AT_LEAST_1000;
+    }
+
+    if (v >= 100000000 / 10) {
+      if (v >= 10000000000000000 / 10) {
+        DoFastIntToBufferBackward<8>(v, end);
+      }
+      DoFastIntToBufferBackward<8>(v, end);
+    }
+
+    if (v >= 10000 / 10) {
+    AT_LEAST_1000:
+      DoFastIntToBufferBackward<4>(v, end);
+    }
+
+    if (v >= 100 / 10) {
+    AT_LEAST_10:
+      DoFastIntToBufferBackward<2>(v, end);
+    }
 
-inline char* EncodeFullU32(uint32_t n, char* out_str) {
-  if (n < 100'000'000) {
-    uint64_t bottom = PrepareTenThousands(n / 10000, n % 10000);
-    ABSL_ASSUME(bottom != 0);
-    // 0 minus 8 to make MSVC happy.
-    uint32_t zeroes = static_cast<uint32_t>(absl::countr_zero(bottom))
-        & (0 - 8ull);
-    uint64_t bottom_res = bottom + kEightZeroBytes;
-    bottom_res >>= zeroes;
-    little_endian::Store64(out_str, bottom_res);
-    return out_str + sizeof(bottom) - zeroes / 8;
+    if (v >= 10 / 10) {
+    AT_LEAST_1:
+      end = DoFastIntToBufferBackward(v, end, std::integral_constant<int, 1>());
+    }
+    return end;
   }
-  uint32_t top = n / 100'000'000;
-  n %= 100'000'000;
-  uint64_t bottom = PrepareTenThousands(n / 10000, n % 10000);
-  uint64_t bottom_res = bottom + kEightZeroBytes;
-  out_str = EncodeHundred(top, out_str);
-  little_endian::Store64(out_str, bottom_res);
-  return out_str + sizeof(bottom);
-}
 
-}  // namespace
+ private:
+  // Only assume pointers are contiguous for now. String and vector iterators
+  // could be special-cased as well, but there's no need for them here.
+  // With C++20 we can probably switch to std::contiguous_iterator_tag.
+  static constexpr bool kIsContiguousIterator =
+      std::is_pointer<BackwardIt>::value;
+
+  template <int Exponent>
+  static void DoFastIntToBufferBackward(T& v, BackwardIt& end) {
+    constexpr T kModulus = Pow<T>(10, Exponent);
+    T remainder = static_cast<T>(v % kModulus);
+    v = static_cast<T>(v / kModulus);
+    end = DoFastIntToBufferBackward(remainder, end,
+                                    std::integral_constant<int, Exponent>());
+  }
 
-void numbers_internal::PutTwoDigits(uint32_t i, char* buf) {
-  assert(i < 100);
-  uint32_t base = kTwoZeroBytes;
-  uint32_t div10 = (i * kDivisionBy10Mul) / kDivisionBy10Div;
-  uint32_t mod10 = i - 10u * div10;
-  base += div10 + (mod10 << 8);
-  little_endian::Store16(buf, static_cast<uint16_t>(base));
-}
+  static BackwardIt DoFastIntToBufferBackward(const T&, BackwardIt end,
+                                              std::integral_constant<int, 0>) {
+    return end;
+  }
 
-char* numbers_internal::FastIntToBuffer(uint32_t n, char* out_str) {
-  if (n < 100) {
-    out_str = EncodeHundred(n, out_str);
-    goto set_last_zero;
+  static BackwardIt DoFastIntToBufferBackward(T v, BackwardIt end,
+                                              std::integral_constant<int, 1>) {
+    *--end = static_cast<char>('0' + v);
+    return DoFastIntToBufferBackward(v, end, std::integral_constant<int, 0>());
   }
-  if (n < 10000) {
-    out_str = EncodeTenThousand(n, out_str);
-    goto set_last_zero;
+
+  static BackwardIt DoFastIntToBufferBackward(T v, BackwardIt end,
+                                              std::integral_constant<int, 4>) {
+    if (kIsContiguousIterator) {
+      const uint32_t digits =
+          PrepareFourDigits(static_cast<uint32_t>(v)) + kFourZeroBytes;
+      end -= sizeof(digits);
+      little_endian::Store32(&*end, digits);
+    } else {
+      uint32_t digits =
+          PrepareFourDigitsReversed(static_cast<uint32_t>(v)) + kFourZeroBytes;
+      for (size_t i = 0; i < sizeof(digits); ++i) {
+        *--end = static_cast<char>(digits);
+        digits >>= CHAR_BIT;
+      }
+    }
+    return end;
   }
-  out_str = EncodeFullU32(n, out_str);
-set_last_zero:
-  *out_str = '\0';
-  return out_str;
-}
 
-char* numbers_internal::FastIntToBuffer(int32_t i, char* buffer) {
-  uint32_t u = static_cast<uint32_t>(i);
-  if (i < 0) {
-    *buffer++ = '-';
-    // We need to do the negation in modular (i.e., "unsigned")
-    // arithmetic; MSVC++ apparently warns for plain "-u", so
-    // we write the equivalent expression "0 - u" instead.
-    u = 0 - u;
+  static BackwardIt DoFastIntToBufferBackward(T v, BackwardIt end,
+                                              std::integral_constant<int, 8>) {
+    if (kIsContiguousIterator) {
+      const uint64_t digits =
+          PrepareEightDigits(static_cast<uint32_t>(v)) + kEightZeroBytes;
+      end -= sizeof(digits);
+      little_endian::Store64(&*end, digits);
+    } else {
+      uint64_t digits = PrepareEightDigitsReversed(static_cast<uint32_t>(v)) +
+                        kEightZeroBytes;
+      for (size_t i = 0; i < sizeof(digits); ++i) {
+        *--end = static_cast<char>(digits);
+        digits >>= CHAR_BIT;
+      }
+    }
+    return end;
   }
-  return numbers_internal::FastIntToBuffer(u, buffer);
-}
 
-char* numbers_internal::FastIntToBuffer(uint64_t i, char* buffer) {
-  uint32_t u32 = static_cast<uint32_t>(i);
-  if (u32 == i) return numbers_internal::FastIntToBuffer(u32, buffer);
-
-  // 10**9 < 2**32 <= i < 10**10, we can do 2+8
-  uint64_t div08 = i / 100'000'000ull;
-  uint64_t mod08 = i % 100'000'000ull;
-  uint64_t mod_result =
-      PrepareTenThousands(mod08 / 10000, mod08 % 10000) + kEightZeroBytes;
-  if (i < 10'000'000'000ull) {
-    buffer = EncodeHundred(static_cast<uint32_t>(div08), buffer);
-    little_endian::Store64(buffer, mod_result);
-    buffer += 8;
-    goto set_last_zero;
+  template <int Digits>
+  static BackwardIt DoFastIntToBufferBackward(
+      T v, BackwardIt end, std::integral_constant<int, Digits>) {
+    constexpr int kLogModulus = Digits - Digits / 2;
+    constexpr T kModulus = Pow(static_cast<T>(10), kLogModulus);
+    bool is_safe_to_use_division_trick = Digits <= 8;
+    T quotient, remainder;
+    if (is_safe_to_use_division_trick) {
+      constexpr uint64_t kCoefficient =
+          ComputePowerOf100DivisionCoefficient<uint64_t>(kLogModulus);
+      quotient = (v * kCoefficient) >> (10 * kLogModulus);
+      remainder = v - quotient * kModulus;
+    } else {
+      quotient = v / kModulus;
+      remainder = v % kModulus;
+    }
+    end = DoFastIntToBufferBackward(remainder, end,
+                                    std::integral_constant<int, kLogModulus>());
+    return DoFastIntToBufferBackward(
+        quotient, end, std::integral_constant<int, Digits - kLogModulus>());
   }
+};
 
-  // i < 10**16, in this case 8+8
-  if (i < 10'000'000'000'000'000ull) {
-    buffer = EncodeFullU32(static_cast<uint32_t>(div08), buffer);
-    little_endian::Store64(buffer, mod_result);
-    buffer += 8;
-    goto set_last_zero;
-  } else {
-    // 4 + 8 + 8
-    uint64_t div016 = i / 10'000'000'000'000'000ull;
-    buffer = EncodeTenThousand(static_cast<uint32_t>(div016), buffer);
-    uint64_t mid_result = div08 - div016 * 100'000'000ull;
-    mid_result = PrepareTenThousands(mid_result / 10000, mid_result % 10000) +
-                 kEightZeroBytes;
-    little_endian::Store64(buffer, mid_result);
-    buffer += 8;
-    little_endian::Store64(buffer, mod_result);
-    buffer += 8;
-    goto set_last_zero;
+// Returns an iterator to the start of the suffix that was appended
+template <typename T, typename BackwardIt>
+std::enable_if_t<std::is_unsigned<T>::value, BackwardIt>
+DoFastIntToBufferBackward(T v, BackwardIt end, uint32_t digits) {
+  using PromotedT = std::decay_t<decltype(+v)>;
+  using Converter = FastUIntToStringConverter<PromotedT, BackwardIt>;
+  (void)digits;
+  return Converter().FastIntToBufferBackward(v, end);
+}
+
+template <typename T, typename BackwardIt>
+std::enable_if_t<std::is_signed<T>::value, BackwardIt>
+DoFastIntToBufferBackward(T v, BackwardIt end, uint32_t digits) {
+  if (absl::numbers_internal::IsNegative(v)) {
+    // Store the minus sign *before* we produce the number itself, not after.
+    // This gets us a tail call.
+    end[-static_cast<ptrdiff_t>(digits) - 1] = '-';
   }
-set_last_zero:
-  *buffer = '\0';
+  return DoFastIntToBufferBackward(
+      absl::numbers_internal::UnsignedAbsoluteValue(v), end, digits);
+}
+
+template <class T>
+std::enable_if_t<std::is_integral<T>::value, int>
+GetNumDigitsOrNegativeIfNegativeImpl(T v) {
+  const auto /* either bool or std::false_type */ is_negative =
+      absl::numbers_internal::IsNegative(v);
+  const int digits = static_cast<int>(absl::numbers_internal::Base10Digits(
+      absl::numbers_internal::UnsignedAbsoluteValue(v)));
+  return is_negative ? ~digits : digits;
+}
+
+}  // namespace
+
+void numbers_internal::PutTwoDigits(uint32_t i, absl::Nonnull<char*> buf) {
+  little_endian::Store16(
+      buf, static_cast<uint16_t>(PrepareTwoDigits(i) + kTwoZeroBytes));
+}
+
+absl::Nonnull<char*> numbers_internal::FastIntToBuffer(
+    uint32_t i, absl::Nonnull<char*> buffer) {
+  const uint32_t digits = absl::numbers_internal::Base10Digits(i);
+  buffer += digits;
+  *buffer = '\0';  // We're going backward, so store this first
+  FastIntToBufferBackward(i, buffer, digits);
   return buffer;
 }
 
-char* numbers_internal::FastIntToBuffer(int64_t i, char* buffer) {
-  uint64_t u = static_cast<uint64_t>(i);
-  if (i < 0) {
-    *buffer++ = '-';
-    u = 0 - u;
-  }
-  return numbers_internal::FastIntToBuffer(u, buffer);
+absl::Nonnull<char*> numbers_internal::FastIntToBuffer(
+    int32_t i, absl::Nonnull<char*> buffer) {
+  buffer += static_cast<int>(i < 0);
+  uint32_t digits = absl::numbers_internal::Base10Digits(
+      absl::numbers_internal::UnsignedAbsoluteValue(i));
+  buffer += digits;
+  *buffer = '\0';  // We're going backward, so store this first
+  FastIntToBufferBackward(i, buffer, digits);
+  return buffer;
+}
+
+absl::Nonnull<char*> numbers_internal::FastIntToBuffer(
+    uint64_t i, absl::Nonnull<char*> buffer) {
+  uint32_t digits = absl::numbers_internal::Base10Digits(i);
+  buffer += digits;
+  *buffer = '\0';  // We're going backward, so store this first
+  FastIntToBufferBackward(i, buffer, digits);
+  return buffer;
+}
+
+absl::Nonnull<char*> numbers_internal::FastIntToBuffer(
+    int64_t i, absl::Nonnull<char*> buffer) {
+  buffer += static_cast<int>(i < 0);
+  uint32_t digits = absl::numbers_internal::Base10Digits(
+      absl::numbers_internal::UnsignedAbsoluteValue(i));
+  buffer += digits;
+  *buffer = '\0';  // We're going backward, so store this first
+  FastIntToBufferBackward(i, buffer, digits);
+  return buffer;
+}
+
+absl::Nonnull<char*> numbers_internal::FastIntToBufferBackward(
+    uint32_t i, absl::Nonnull<char*> buffer_end, uint32_t exact_digit_count) {
+  return DoFastIntToBufferBackward(i, buffer_end, exact_digit_count);
+}
+
+absl::Nonnull<char*> numbers_internal::FastIntToBufferBackward(
+    int32_t i, absl::Nonnull<char*> buffer_end, uint32_t exact_digit_count) {
+  return DoFastIntToBufferBackward(i, buffer_end, exact_digit_count);
+}
+
+absl::Nonnull<char*> numbers_internal::FastIntToBufferBackward(
+    uint64_t i, absl::Nonnull<char*> buffer_end, uint32_t exact_digit_count) {
+  return DoFastIntToBufferBackward(i, buffer_end, exact_digit_count);
+}
+
+absl::Nonnull<char*> numbers_internal::FastIntToBufferBackward(
+    int64_t i, absl::Nonnull<char*> buffer_end, uint32_t exact_digit_count) {
+  return DoFastIntToBufferBackward(i, buffer_end, exact_digit_count);
+}
+
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(signed char v) {
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(unsigned char v) {
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(short v) {  // NOLINT
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(
+    unsigned short v) {  // NOLINT
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(int v) {
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(unsigned int v) {
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(long v) {  // NOLINT
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(
+    unsigned long v) {  // NOLINT
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(long long v) {  // NOLINT
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
+}
+int numbers_internal::GetNumDigitsOrNegativeIfNegative(
+    unsigned long long v) {  // NOLINT
+  return GetNumDigitsOrNegativeIfNegativeImpl(v);
 }
 
 // Given a 128-bit number expressed as a pair of uint64_t, high half first,
@@ -534,7 +769,8 @@ static ExpDigits SplitToSix(const double value) {
 
 // Helper function for fast formatting of floating-point.
 // The result is the same as "%g", a.k.a. "%.6g".
-size_t numbers_internal::SixDigitsToBuffer(double d, char* const buffer) {
+size_t numbers_internal::SixDigitsToBuffer(double d,
+                                           absl::Nonnull<char*> const buffer) {
   static_assert(std::numeric_limits<float>::is_iec559,
                 "IEEE-754/IEC-559 support only");
 
@@ -681,9 +917,10 @@ static const int8_t kAsciiToInt[256] = {
     36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36};
 
 // Parse the sign and optional hex or oct prefix in text.
-inline bool safe_parse_sign_and_base(absl::string_view* text /*inout*/,
-                                     int* base_ptr /*inout*/,
-                                     bool* negative_ptr /*output*/) {
+inline bool safe_parse_sign_and_base(
+    absl::Nonnull<absl::string_view*> text /*inout*/,
+    absl::Nonnull<int*> base_ptr /*inout*/,
+    absl::Nonnull<bool*> negative_ptr /*output*/) {
   if (text->data() == nullptr) {
     return false;
   }
@@ -968,7 +1205,7 @@ ABSL_CONST_INIT const IntType LookupTables<IntType>::kVminOverBase[] =
 
 template <typename IntType>
 inline bool safe_parse_positive_int(absl::string_view text, int base,
-                                    IntType* value_p) {
+                                    absl::Nonnull<IntType*> value_p) {
   IntType value = 0;
   const IntType vmax = std::numeric_limits<IntType>::max();
   assert(vmax > 0);
@@ -1005,7 +1242,7 @@ inline bool safe_parse_positive_int(absl::string_view text, int base,
 
 template <typename IntType>
 inline bool safe_parse_negative_int(absl::string_view text, int base,
-                                    IntType* value_p) {
+                                    absl::Nonnull<IntType*> value_p) {
   IntType value = 0;
   const IntType vmin = std::numeric_limits<IntType>::min();
   assert(vmin < 0);
@@ -1049,8 +1286,8 @@ inline bool safe_parse_negative_int(absl::string_view text, int base,
 // Input format based on POSIX.1-2008 strtol
 // http://pubs.opengroup.org/onlinepubs/9699919799/functions/strtol.html
 template <typename IntType>
-inline bool safe_int_internal(absl::string_view text, IntType* value_p,
-                              int base) {
+inline bool safe_int_internal(absl::string_view text,
+                              absl::Nonnull<IntType*> value_p, int base) {
   *value_p = 0;
   bool negative;
   if (!safe_parse_sign_and_base(&text, &base, &negative)) {
@@ -1064,8 +1301,8 @@ inline bool safe_int_internal(absl::string_view text, IntType* value_p,
 }
 
 template <typename IntType>
-inline bool safe_uint_internal(absl::string_view text, IntType* value_p,
-                               int base) {
+inline bool safe_uint_internal(absl::string_view text,
+                               absl::Nonnull<IntType*> value_p, int base) {
   *value_p = 0;
   bool negative;
   if (!safe_parse_sign_and_base(&text, &base, &negative) || negative) {
@@ -1099,27 +1336,33 @@ ABSL_CONST_INIT ABSL_DLL const char kHexTable[513] =
     "e0e1e2e3e4e5e6e7e8e9eaebecedeeef"
     "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff";
 
-bool safe_strto32_base(absl::string_view text, int32_t* value, int base) {
+bool safe_strto32_base(absl::string_view text, absl::Nonnull<int32_t*> value,
+                       int base) {
   return safe_int_internal<int32_t>(text, value, base);
 }
 
-bool safe_strto64_base(absl::string_view text, int64_t* value, int base) {
+bool safe_strto64_base(absl::string_view text, absl::Nonnull<int64_t*> value,
+                       int base) {
   return safe_int_internal<int64_t>(text, value, base);
 }
 
-bool safe_strto128_base(absl::string_view text, int128* value, int base) {
+bool safe_strto128_base(absl::string_view text, absl::Nonnull<int128*> value,
+                        int base) {
   return safe_int_internal<absl::int128>(text, value, base);
 }
 
-bool safe_strtou32_base(absl::string_view text, uint32_t* value, int base) {
+bool safe_strtou32_base(absl::string_view text, absl::Nonnull<uint32_t*> value,
+                        int base) {
   return safe_uint_internal<uint32_t>(text, value, base);
 }
 
-bool safe_strtou64_base(absl::string_view text, uint64_t* value, int base) {
+bool safe_strtou64_base(absl::string_view text, absl::Nonnull<uint64_t*> value,
+                        int base) {
   return safe_uint_internal<uint64_t>(text, value, base);
 }
 
-bool safe_strtou128_base(absl::string_view text, uint128* value, int base) {
+bool safe_strtou128_base(absl::string_view text, absl::Nonnull<uint128*> value,
+                         int base) {
   return safe_uint_internal<absl::uint128>(text, value, base);
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/numbers.h b/contrib/restricted/abseil-cpp/absl/strings/numbers.h
index d7630cef9c..ad4e66b634 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/numbers.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/numbers.h
@@ -32,6 +32,7 @@
 #endif
 
 #include <cstddef>
+#include <cstdint>
 #include <cstdlib>
 #include <cstring>
 #include <ctime>
@@ -39,9 +40,12 @@
 #include <string>
 #include <type_traits>
 
+#include "absl/base/attributes.h"
 #include "absl/base/config.h"
 #include "absl/base/internal/endian.h"
 #include "absl/base/macros.h"
+#include "absl/base/nullability.h"
+#include "absl/base/optimization.h"
 #include "absl/base/port.h"
 #include "absl/numeric/bits.h"
 #include "absl/numeric/int128.h"
@@ -59,7 +63,8 @@ ABSL_NAMESPACE_BEGIN
 // encountered, this function returns `false`, leaving `out` in an unspecified
 // state.
 template <typename int_type>
-ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str, int_type* out);
+ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str,
+                                     absl::Nonnull<int_type*> out);
 
 // SimpleAtof()
 //
@@ -70,7 +75,8 @@ ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str, int_type* out);
 // allowed formats for `str`, except SimpleAtof() is locale-independent and will
 // always use the "C" locale. If any errors are encountered, this function
 // returns `false`, leaving `out` in an unspecified state.
-ABSL_MUST_USE_RESULT bool SimpleAtof(absl::string_view str, float* out);
+ABSL_MUST_USE_RESULT bool SimpleAtof(absl::string_view str,
+                                     absl::Nonnull<float*> out);
 
 // SimpleAtod()
 //
@@ -81,7 +87,8 @@ ABSL_MUST_USE_RESULT bool SimpleAtof(absl::string_view str, float* out);
 // allowed formats for `str`, except SimpleAtod is locale-independent and will
 // always use the "C" locale. If any errors are encountered, this function
 // returns `false`, leaving `out` in an unspecified state.
-ABSL_MUST_USE_RESULT bool SimpleAtod(absl::string_view str, double* out);
+ABSL_MUST_USE_RESULT bool SimpleAtod(absl::string_view str,
+                                     absl::Nonnull<double*> out);
 
 // SimpleAtob()
 //
@@ -91,7 +98,8 @@ ABSL_MUST_USE_RESULT bool SimpleAtod(absl::string_view str, double* out);
 // are interpreted as boolean `false`: "false", "f", "no", "n", "0". If any
 // errors are encountered, this function returns `false`, leaving `out` in an
 // unspecified state.
-ABSL_MUST_USE_RESULT bool SimpleAtob(absl::string_view str, bool* out);
+ABSL_MUST_USE_RESULT bool SimpleAtob(absl::string_view str,
+                                     absl::Nonnull<bool*> out);
 
 // SimpleHexAtoi()
 //
@@ -104,13 +112,14 @@ ABSL_MUST_USE_RESULT bool SimpleAtob(absl::string_view str, bool* out);
 // by this function. If any errors are encountered, this function returns
 // `false`, leaving `out` in an unspecified state.
 template <typename int_type>
-ABSL_MUST_USE_RESULT bool SimpleHexAtoi(absl::string_view str, int_type* out);
+ABSL_MUST_USE_RESULT bool SimpleHexAtoi(absl::string_view str,
+                                        absl::Nonnull<int_type*> out);
 
 // Overloads of SimpleHexAtoi() for 128 bit integers.
-ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(absl::string_view str,
-                                               absl::int128* out);
-ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(absl::string_view str,
-                                               absl::uint128* out);
+ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(
+    absl::string_view str, absl::Nonnull<absl::int128*> out);
+ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(
+    absl::string_view str, absl::Nonnull<absl::uint128*> out);
 
 ABSL_NAMESPACE_END
 }  // namespace absl
@@ -132,42 +141,136 @@ ABSL_DLL extern const char
 //   PutTwoDigits(42, buf);
 //   // buf[0] == '4'
 //   // buf[1] == '2'
-void PutTwoDigits(uint32_t i, char* buf);
+void PutTwoDigits(uint32_t i, absl::Nonnull<char*> buf);
 
 // safe_strto?() functions for implementing SimpleAtoi()
 
-bool safe_strto32_base(absl::string_view text, int32_t* value, int base);
-bool safe_strto64_base(absl::string_view text, int64_t* value, int base);
-bool safe_strto128_base(absl::string_view text, absl::int128* value,
-                         int base);
-bool safe_strtou32_base(absl::string_view text, uint32_t* value, int base);
-bool safe_strtou64_base(absl::string_view text, uint64_t* value, int base);
-bool safe_strtou128_base(absl::string_view text, absl::uint128* value,
-                         int base);
+bool safe_strto32_base(absl::string_view text, absl::Nonnull<int32_t*> value,
+                       int base);
+bool safe_strto64_base(absl::string_view text, absl::Nonnull<int64_t*> value,
+                       int base);
+bool safe_strto128_base(absl::string_view text,
+                        absl::Nonnull<absl::int128*> value, int base);
+bool safe_strtou32_base(absl::string_view text, absl::Nonnull<uint32_t*> value,
+                        int base);
+bool safe_strtou64_base(absl::string_view text, absl::Nonnull<uint64_t*> value,
+                        int base);
+bool safe_strtou128_base(absl::string_view text,
+                         absl::Nonnull<absl::uint128*> value, int base);
 
 static const int kFastToBufferSize = 32;
 static const int kSixDigitsToBufferSize = 16;
 
+template <class T>
+std::enable_if_t<!std::is_unsigned<T>::value, bool> IsNegative(const T& v) {
+  return v < T();
+}
+
+template <class T>
+std::enable_if_t<std::is_unsigned<T>::value, std::false_type> IsNegative(
+    const T&) {
+  // The integer is unsigned, so return a compile-time constant.
+  // This can help the optimizer avoid having to prove bool to be false later.
+  return std::false_type();
+}
+
+template <class T>
+std::enable_if_t<std::is_unsigned<std::decay_t<T>>::value, T&&>
+UnsignedAbsoluteValue(T&& v ABSL_ATTRIBUTE_LIFETIME_BOUND) {
+  // The value is unsigned; just return the original.
+  return std::forward<T>(v);
+}
+
+template <class T>
+ABSL_ATTRIBUTE_CONST_FUNCTION
+    std::enable_if_t<!std::is_unsigned<T>::value, std::make_unsigned_t<T>>
+    UnsignedAbsoluteValue(T v) {
+  using U = std::make_unsigned_t<T>;
+  return IsNegative(v) ? U() - static_cast<U>(v) : static_cast<U>(v);
+}
+
+// Returns the number of base-10 digits in the given number.
+// Note that this strictly counts digits. It does not count the sign.
+// The `initial_digits` parameter is the starting point, which is normally equal
+// to 1 because the number of digits in 0 is 1 (a special case).
+// However, callers may e.g. wish to change it to 2 to account for the sign.
+template <typename T>
+std::enable_if_t<std::is_unsigned<T>::value, uint32_t> Base10Digits(
+    T v, const uint32_t initial_digits = 1) {
+  uint32_t r = initial_digits;
+  // If code size becomes an issue, the 'if' stage can be removed for a minor
+  // performance loss.
+  for (;;) {
+    if (ABSL_PREDICT_TRUE(v < 10 * 10)) {
+      r += (v >= 10);
+      break;
+    }
+    if (ABSL_PREDICT_TRUE(v < 1000 * 10)) {
+      r += (v >= 1000) + 2;
+      break;
+    }
+    if (ABSL_PREDICT_TRUE(v < 100000 * 10)) {
+      r += (v >= 100000) + 4;
+      break;
+    }
+    r += 6;
+    v = static_cast<T>(v / 1000000);
+  }
+  return r;
+}
+
+template <typename T>
+std::enable_if_t<std::is_signed<T>::value, uint32_t> Base10Digits(
+    T v, uint32_t r = 1) {
+  // Branchlessly add 1 to account for a minus sign.
+  r += static_cast<uint32_t>(IsNegative(v));
+  return Base10Digits(UnsignedAbsoluteValue(v), r);
+}
+
+// These functions return the number of base-10 digits, but multiplied by -1 if
+// the input itself is negative. This is handy and efficient for later usage,
+// since the bitwise complement of the result becomes equal to the number of
+// characters required.
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    signed char v);
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    unsigned char v);
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    short v);  // NOLINT
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    unsigned short v);  // NOLINT
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(int v);
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    unsigned int v);
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    long v);  // NOLINT
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    unsigned long v);  // NOLINT
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    long long v);  // NOLINT
+ABSL_ATTRIBUTE_CONST_FUNCTION int GetNumDigitsOrNegativeIfNegative(
+    unsigned long long v);  // NOLINT
+
 // Helper function for fast formatting of floating-point values.
 // The result is the same as printf's "%g", a.k.a. "%.6g"; that is, six
 // significant digits are returned, trailing zeros are removed, and numbers
 // outside the range 0.0001-999999 are output using scientific notation
 // (1.23456e+06). This routine is heavily optimized.
 // Required buffer size is `kSixDigitsToBufferSize`.
-size_t SixDigitsToBuffer(double d, char* buffer);
+size_t SixDigitsToBuffer(double d, absl::Nonnull<char*> buffer);
 
-// These functions are intended for speed. All functions take an output buffer
+// All of these functions take an output buffer
 // as an argument and return a pointer to the last byte they wrote, which is the
 // terminating '\0'. At most `kFastToBufferSize` bytes are written.
-char* FastIntToBuffer(int32_t, char*);
-char* FastIntToBuffer(uint32_t, char*);
-char* FastIntToBuffer(int64_t, char*);
-char* FastIntToBuffer(uint64_t, char*);
+absl::Nonnull<char*> FastIntToBuffer(int32_t i, absl::Nonnull<char*> buffer);
+absl::Nonnull<char*> FastIntToBuffer(uint32_t i, absl::Nonnull<char*> buffer);
+absl::Nonnull<char*> FastIntToBuffer(int64_t i, absl::Nonnull<char*> buffer);
+absl::Nonnull<char*> FastIntToBuffer(uint64_t i, absl::Nonnull<char*> buffer);
 
 // For enums and integer types that are not an exact match for the types above,
 // use templates to call the appropriate one of the four overloads above.
 template <typename int_type>
-char* FastIntToBuffer(int_type i, char* buffer) {
+absl::Nonnull<char*> FastIntToBuffer(int_type i, absl::Nonnull<char*> buffer) {
   static_assert(sizeof(i) <= 64 / 8,
                 "FastIntToBuffer works only with 64-bit-or-less integers.");
   // TODO(jorg): This signed-ness check is used because it works correctly
@@ -191,10 +294,63 @@ char* FastIntToBuffer(int_type i, char* buffer) {
   }
 }
 
+// These functions do NOT add any null-terminator.
+// They return a pointer to the beginning of the written string.
+// The digit counts provided must *exactly* match the number of base-10 digits
+// in the number, or the behavior is undefined.
+// (i.e. do NOT count the minus sign, or over- or under-count the digits.)
+absl::Nonnull<char*> FastIntToBufferBackward(int32_t i,
+                                             absl::Nonnull<char*> buffer_end,
+                                             uint32_t exact_digit_count);
+absl::Nonnull<char*> FastIntToBufferBackward(uint32_t i,
+                                             absl::Nonnull<char*> buffer_end,
+                                             uint32_t exact_digit_count);
+absl::Nonnull<char*> FastIntToBufferBackward(int64_t i,
+                                             absl::Nonnull<char*> buffer_end,
+                                             uint32_t exact_digit_count);
+absl::Nonnull<char*> FastIntToBufferBackward(uint64_t i,
+                                             absl::Nonnull<char*> buffer_end,
+                                             uint32_t exact_digit_count);
+
+// For enums and integer types that are not an exact match for the types above,
+// use templates to call the appropriate one of the four overloads above.
+template <typename int_type>
+absl::Nonnull<char*> FastIntToBufferBackward(int_type i,
+                                             absl::Nonnull<char*> buffer_end,
+                                             uint32_t exact_digit_count) {
+  static_assert(
+      sizeof(i) <= 64 / 8,
+      "FastIntToBufferBackward works only with 64-bit-or-less integers.");
+  // This signed-ness check is used because it works correctly
+  // with enums, and it also serves to check that int_type is not a pointer.
+  // If one day something like std::is_signed<enum E> works, switch to it.
+  // These conditions are constexpr bools to suppress MSVC warning C4127.
+  constexpr bool kIsSigned = static_cast<int_type>(1) - 2 < 0;
+  constexpr bool kUse64Bit = sizeof(i) > 32 / 8;
+  if (kIsSigned) {
+    if (kUse64Bit) {
+      return FastIntToBufferBackward(static_cast<int64_t>(i), buffer_end,
+                                     exact_digit_count);
+    } else {
+      return FastIntToBufferBackward(static_cast<int32_t>(i), buffer_end,
+                                     exact_digit_count);
+    }
+  } else {
+    if (kUse64Bit) {
+      return FastIntToBufferBackward(static_cast<uint64_t>(i), buffer_end,
+                                     exact_digit_count);
+    } else {
+      return FastIntToBufferBackward(static_cast<uint32_t>(i), buffer_end,
+                                     exact_digit_count);
+    }
+  }
+}
+
 // Implementation of SimpleAtoi, generalized to support arbitrary base (used
 // with base different from 10 elsewhere in Abseil implementation).
 template <typename int_type>
-ABSL_MUST_USE_RESULT bool safe_strtoi_base(absl::string_view s, int_type* out,
+ABSL_MUST_USE_RESULT bool safe_strtoi_base(absl::string_view s,
+                                           absl::Nonnull<int_type*> out,
                                            int base) {
   static_assert(sizeof(*out) == 4 || sizeof(*out) == 8,
                 "SimpleAtoi works only with 32-bit or 64-bit integers.");
@@ -237,7 +393,7 @@ ABSL_MUST_USE_RESULT bool safe_strtoi_base(absl::string_view s, int_type* out,
 // without the terminating null character. Thus `out` must be of length >= 16.
 // Returns the number of non-pad digits of the output (it can never be zero
 // since 0 has one digit).
-inline size_t FastHexToBufferZeroPad16(uint64_t val, char* out) {
+inline size_t FastHexToBufferZeroPad16(uint64_t val, absl::Nonnull<char*> out) {
 #ifdef ABSL_INTERNAL_HAVE_SSSE3
   uint64_t be = absl::big_endian::FromHost64(val);
   const auto kNibbleMask = _mm_set1_epi8(0xf);
@@ -263,32 +419,34 @@ inline size_t FastHexToBufferZeroPad16(uint64_t val, char* out) {
 }  // namespace numbers_internal
 
 template <typename int_type>
-ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str, int_type* out) {
+ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str,
+                                     absl::Nonnull<int_type*> out) {
   return numbers_internal::safe_strtoi_base(str, out, 10);
 }
 
 ABSL_MUST_USE_RESULT inline bool SimpleAtoi(absl::string_view str,
-                                            absl::int128* out) {
+                                            absl::Nonnull<absl::int128*> out) {
   return numbers_internal::safe_strto128_base(str, out, 10);
 }
 
 ABSL_MUST_USE_RESULT inline bool SimpleAtoi(absl::string_view str,
-                                            absl::uint128* out) {
+                                            absl::Nonnull<absl::uint128*> out) {
   return numbers_internal::safe_strtou128_base(str, out, 10);
 }
 
 template <typename int_type>
-ABSL_MUST_USE_RESULT bool SimpleHexAtoi(absl::string_view str, int_type* out) {
+ABSL_MUST_USE_RESULT bool SimpleHexAtoi(absl::string_view str,
+                                        absl::Nonnull<int_type*> out) {
   return numbers_internal::safe_strtoi_base(str, out, 16);
 }
 
-ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(absl::string_view str,
-                                               absl::int128* out) {
+ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(
+    absl::string_view str, absl::Nonnull<absl::int128*> out) {
   return numbers_internal::safe_strto128_base(str, out, 16);
 }
 
-ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(absl::string_view str,
-                                               absl::uint128* out) {
+ABSL_MUST_USE_RESULT inline bool SimpleHexAtoi(
+    absl::string_view str, absl::Nonnull<absl::uint128*> out) {
   return numbers_internal::safe_strtou128_base(str, out, 16);
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_cat.cc b/contrib/restricted/abseil-cpp/absl/strings/str_cat.cc
index 2e49c31b68..098ab18388 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_cat.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_cat.cc
@@ -16,13 +16,15 @@
 
 #include <assert.h>
 
-#include <algorithm>
 #include <cstddef>
 #include <cstdint>
 #include <cstring>
+#include <initializer_list>
 #include <string>
+#include <type_traits>
 
-#include "absl/strings/ascii.h"
+#include "absl/base/config.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/internal/resize_uninitialized.h"
 #include "absl/strings/numbers.h"
 #include "absl/strings/string_view.h"
@@ -30,6 +32,7 @@
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
+
 // ----------------------------------------------------------------------
 // StrCat()
 //    This merges the given strings or integers, with no delimiter. This
@@ -37,9 +40,10 @@ ABSL_NAMESPACE_BEGIN
 //    of a mix of raw C strings, string_views, strings, and integer values.
 // ----------------------------------------------------------------------
 
+namespace {
 // Append is merely a version of memcpy that returns the address of the byte
 // after the area just overwritten.
-static char* Append(char* out, const AlphaNum& x) {
+absl::Nonnull<char*> Append(absl::Nonnull<char*> out, const AlphaNum& x) {
   // memcpy is allowed to overwrite arbitrary memory, so doing this after the
   // call would force an extra fetch of x.size().
   char* after = out + x.size();
@@ -49,6 +53,8 @@ static char* Append(char* out, const AlphaNum& x) {
   return after;
 }
 
+}  // namespace
+
 std::string StrCat(const AlphaNum& a, const AlphaNum& b) {
   std::string result;
   absl::strings_internal::STLStringResizeUninitialized(&result,
@@ -92,6 +98,130 @@ std::string StrCat(const AlphaNum& a, const AlphaNum& b, const AlphaNum& c,
 namespace strings_internal {
 
 // Do not call directly - these are not part of the public API.
+void STLStringAppendUninitializedAmortized(std::string* dest,
+                                           size_t to_append) {
+  strings_internal::AppendUninitializedTraits<std::string>::Append(dest,
+                                                                   to_append);
+}
+
+template <typename Integer>
+std::enable_if_t<std::is_integral<Integer>::value, std::string> IntegerToString(
+    Integer i) {
+  std::string str;
+  const auto /* either bool or std::false_type */ is_negative =
+      absl::numbers_internal::IsNegative(i);
+  const uint32_t digits = absl::numbers_internal::Base10Digits(
+      absl::numbers_internal::UnsignedAbsoluteValue(i));
+  absl::strings_internal::STLStringResizeUninitialized(
+      &str, digits + static_cast<uint32_t>(is_negative));
+  absl::numbers_internal::FastIntToBufferBackward(i, &str[str.size()], digits);
+  return str;
+}
+
+template <>
+std::string IntegerToString(long i) {  // NOLINT
+  if (sizeof(i) <= sizeof(int)) {
+    return IntegerToString(static_cast<int>(i));
+  } else {
+    return IntegerToString(static_cast<long long>(i));  // NOLINT
+  }
+}
+
+template <>
+std::string IntegerToString(unsigned long i) {  // NOLINT
+  if (sizeof(i) <= sizeof(unsigned int)) {
+    return IntegerToString(static_cast<unsigned int>(i));
+  } else {
+    return IntegerToString(static_cast<unsigned long long>(i));  // NOLINT
+  }
+}
+
+template <typename Float>
+std::enable_if_t<std::is_floating_point<Float>::value, std::string>
+FloatToString(Float f) {
+  std::string result;
+  strings_internal::STLStringResizeUninitialized(
+      &result, numbers_internal::kSixDigitsToBufferSize);
+  char* start = &result[0];
+  result.erase(numbers_internal::SixDigitsToBuffer(f, start));
+  return result;
+}
+
+std::string SingleArgStrCat(int x) { return IntegerToString(x); }
+std::string SingleArgStrCat(unsigned int x) { return IntegerToString(x); }
+// NOLINTNEXTLINE
+std::string SingleArgStrCat(long x) { return IntegerToString(x); }
+// NOLINTNEXTLINE
+std::string SingleArgStrCat(unsigned long x) { return IntegerToString(x); }
+// NOLINTNEXTLINE
+std::string SingleArgStrCat(long long x) { return IntegerToString(x); }
+// NOLINTNEXTLINE
+std::string SingleArgStrCat(unsigned long long x) { return IntegerToString(x); }
+std::string SingleArgStrCat(float x) { return FloatToString(x); }
+std::string SingleArgStrCat(double x) { return FloatToString(x); }
+
+template <class Integer>
+std::enable_if_t<std::is_integral<Integer>::value, void> AppendIntegerToString(
+    std::string& str, Integer i) {
+  const auto /* either bool or std::false_type */ is_negative =
+      absl::numbers_internal::IsNegative(i);
+  const uint32_t digits = absl::numbers_internal::Base10Digits(
+      absl::numbers_internal::UnsignedAbsoluteValue(i));
+  absl::strings_internal::STLStringAppendUninitializedAmortized(
+      &str, digits + static_cast<uint32_t>(is_negative));
+  absl::numbers_internal::FastIntToBufferBackward(i, &str[str.size()], digits);
+}
+
+template <>
+void AppendIntegerToString(std::string& str, long i) {  // NOLINT
+  if (sizeof(i) <= sizeof(int)) {
+    return AppendIntegerToString(str, static_cast<int>(i));
+  } else {
+    return AppendIntegerToString(str, static_cast<long long>(i));  // NOLINT
+  }
+}
+
+template <>
+void AppendIntegerToString(std::string& str,
+                           unsigned long i) {  // NOLINT
+  if (sizeof(i) <= sizeof(unsigned int)) {
+    return AppendIntegerToString(str, static_cast<unsigned int>(i));
+  } else {
+    return AppendIntegerToString(str,
+                                 static_cast<unsigned long long>(i));  // NOLINT
+  }
+}
+
+// `SingleArgStrAppend` overloads are defined here for the same reasons as with
+// `SingleArgStrCat` above.
+void SingleArgStrAppend(std::string& str, int x) {
+  return AppendIntegerToString(str, x);
+}
+
+void SingleArgStrAppend(std::string& str, unsigned int x) {
+  return AppendIntegerToString(str, x);
+}
+
+// NOLINTNEXTLINE
+void SingleArgStrAppend(std::string& str, long x) {
+  return AppendIntegerToString(str, x);
+}
+
+// NOLINTNEXTLINE
+void SingleArgStrAppend(std::string& str, unsigned long x) {
+  return AppendIntegerToString(str, x);
+}
+
+// NOLINTNEXTLINE
+void SingleArgStrAppend(std::string& str, long long x) {
+  return AppendIntegerToString(str, x);
+}
+
+// NOLINTNEXTLINE
+void SingleArgStrAppend(std::string& str, unsigned long long x) {
+  return AppendIntegerToString(str, x);
+}
+
 std::string CatPieces(std::initializer_list<absl::string_view> pieces) {
   std::string result;
   size_t total_size = 0;
@@ -120,15 +250,15 @@ std::string CatPieces(std::initializer_list<absl::string_view> pieces) {
   assert(((src).size() == 0) ||      \
          (uintptr_t((src).data() - (dest).data()) > uintptr_t((dest).size())))
 
-void AppendPieces(std::string* dest,
+void AppendPieces(absl::Nonnull<std::string*> dest,
                   std::initializer_list<absl::string_view> pieces) {
   size_t old_size = dest->size();
-  size_t total_size = old_size;
+  size_t to_append = 0;
   for (absl::string_view piece : pieces) {
     ASSERT_NO_OVERLAP(*dest, piece);
-    total_size += piece.size();
+    to_append += piece.size();
   }
-  strings_internal::STLStringResizeUninitializedAmortized(dest, total_size);
+  strings_internal::STLStringAppendUninitializedAmortized(dest, to_append);
 
   char* const begin = &(*dest)[0];
   char* out = begin + old_size;
@@ -144,23 +274,23 @@ void AppendPieces(std::string* dest,
 
 }  // namespace strings_internal
 
-void StrAppend(std::string* dest, const AlphaNum& a) {
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a) {
   ASSERT_NO_OVERLAP(*dest, a);
   std::string::size_type old_size = dest->size();
-  strings_internal::STLStringResizeUninitializedAmortized(dest,
-                                                          old_size + a.size());
+  strings_internal::STLStringAppendUninitializedAmortized(dest, a.size());
   char* const begin = &(*dest)[0];
   char* out = begin + old_size;
   out = Append(out, a);
   assert(out == begin + dest->size());
 }
 
-void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b) {
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a,
+               const AlphaNum& b) {
   ASSERT_NO_OVERLAP(*dest, a);
   ASSERT_NO_OVERLAP(*dest, b);
   std::string::size_type old_size = dest->size();
-  strings_internal::STLStringResizeUninitializedAmortized(
-      dest, old_size + a.size() + b.size());
+  strings_internal::STLStringAppendUninitializedAmortized(dest,
+                                                          a.size() + b.size());
   char* const begin = &(*dest)[0];
   char* out = begin + old_size;
   out = Append(out, a);
@@ -168,14 +298,14 @@ void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b) {
   assert(out == begin + dest->size());
 }
 
-void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b,
-               const AlphaNum& c) {
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a,
+               const AlphaNum& b, const AlphaNum& c) {
   ASSERT_NO_OVERLAP(*dest, a);
   ASSERT_NO_OVERLAP(*dest, b);
   ASSERT_NO_OVERLAP(*dest, c);
   std::string::size_type old_size = dest->size();
-  strings_internal::STLStringResizeUninitializedAmortized(
-      dest, old_size + a.size() + b.size() + c.size());
+  strings_internal::STLStringAppendUninitializedAmortized(
+      dest, a.size() + b.size() + c.size());
   char* const begin = &(*dest)[0];
   char* out = begin + old_size;
   out = Append(out, a);
@@ -184,15 +314,15 @@ void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b,
   assert(out == begin + dest->size());
 }
 
-void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b,
-               const AlphaNum& c, const AlphaNum& d) {
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a,
+               const AlphaNum& b, const AlphaNum& c, const AlphaNum& d) {
   ASSERT_NO_OVERLAP(*dest, a);
   ASSERT_NO_OVERLAP(*dest, b);
   ASSERT_NO_OVERLAP(*dest, c);
   ASSERT_NO_OVERLAP(*dest, d);
   std::string::size_type old_size = dest->size();
-  strings_internal::STLStringResizeUninitializedAmortized(
-      dest, old_size + a.size() + b.size() + c.size() + d.size());
+  strings_internal::STLStringAppendUninitializedAmortized(
+      dest, a.size() + b.size() + c.size() + d.size());
   char* const begin = &(*dest)[0];
   char* out = begin + old_size;
   out = Append(out, a);
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_cat.h b/contrib/restricted/abseil-cpp/absl/strings/str_cat.h
index d5f71ff003..ea2c4dcad8 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_cat.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_cat.h
@@ -89,6 +89,8 @@
 
 #include <algorithm>
 #include <array>
+#include <cassert>
+#include <cstddef>
 #include <cstdint>
 #include <cstring>
 #include <string>
@@ -97,8 +99,11 @@
 #include <vector>
 
 #include "absl/base/attributes.h"
+#include "absl/base/nullability.h"
 #include "absl/base/port.h"
-#include "absl/strings/internal/has_absl_stringify.h"
+#include "absl/meta/type_traits.h"
+#include "absl/strings/has_absl_stringify.h"
+#include "absl/strings/internal/resize_uninitialized.h"
 #include "absl/strings/internal/stringify_sink.h"
 #include "absl/strings/numbers.h"
 #include "absl/strings/string_view.h"
@@ -201,7 +206,7 @@ struct Hex {
                               !std::is_pointer<Int>::value>::type* = nullptr)
       : Hex(spec, static_cast<uint64_t>(v)) {}
   template <typename Pointee>
-  explicit Hex(Pointee* v, PadSpec spec = absl::kNoPad)
+  explicit Hex(absl::Nullable<Pointee*> v, PadSpec spec = absl::kNoPad)
       : Hex(spec, reinterpret_cast<uintptr_t>(v)) {}
 
   template <typename S>
@@ -253,10 +258,9 @@ struct Dec {
                typename std::enable_if<(sizeof(Int) <= 8)>::type* = nullptr)
       : value(v >= 0 ? static_cast<uint64_t>(v)
                      : uint64_t{0} - static_cast<uint64_t>(v)),
-        width(spec == absl::kNoPad
-                  ? 1
-                  : spec >= absl::kSpacePad2 ? spec - absl::kSpacePad2 + 2
-                                             : spec - absl::kZeroPad2 + 2),
+        width(spec == absl::kNoPad       ? 1
+              : spec >= absl::kSpacePad2 ? spec - absl::kSpacePad2 + 2
+                                         : spec - absl::kZeroPad2 + 2),
         fill(spec >= absl::kSpacePad2 ? ' ' : '0'),
         neg(v < 0) {}
 
@@ -344,7 +348,7 @@ class AlphaNum {
           ABSL_ATTRIBUTE_LIFETIME_BOUND)
       : piece_(&buf.data[0], buf.size) {}
 
-  AlphaNum(const char* c_str  // NOLINT(runtime/explicit)
+  AlphaNum(absl::Nullable<const char*> c_str  // NOLINT(runtime/explicit)
                ABSL_ATTRIBUTE_LIFETIME_BOUND)
       : piece_(NullSafeStringView(c_str)) {}
   AlphaNum(absl::string_view pc  // NOLINT(runtime/explicit)
@@ -352,7 +356,7 @@ class AlphaNum {
       : piece_(pc) {}
 
   template <typename T, typename = typename std::enable_if<
-                            strings_internal::HasAbslStringify<T>::value>::type>
+                            HasAbslStringify<T>::value>::type>
   AlphaNum(  // NOLINT(runtime/explicit)
       const T& v ABSL_ATTRIBUTE_LIFETIME_BOUND,
       strings_internal::StringifySink&& sink ABSL_ATTRIBUTE_LIFETIME_BOUND = {})
@@ -371,7 +375,7 @@ class AlphaNum {
   AlphaNum& operator=(const AlphaNum&) = delete;
 
   absl::string_view::size_type size() const { return piece_.size(); }
-  const char* data() const { return piece_.data(); }
+  absl::Nullable<const char*> data() const { return piece_.data(); }
   absl::string_view Piece() const { return piece_; }
 
   // Match unscoped enums.  Use integral promotion so that a `char`-backed
@@ -379,17 +383,17 @@ class AlphaNum {
   template <typename T,
             typename = typename std::enable_if<
                 std::is_enum<T>{} && std::is_convertible<T, int>{} &&
-                !strings_internal::HasAbslStringify<T>::value>::type>
+                !HasAbslStringify<T>::value>::type>
   AlphaNum(T e)  // NOLINT(runtime/explicit)
       : AlphaNum(+e) {}
 
   // This overload matches scoped enums.  We must explicitly cast to the
   // underlying type, but use integral promotion for the same reason as above.
   template <typename T,
-            typename std::enable_if<
-                std::is_enum<T>{} && !std::is_convertible<T, int>{} &&
-                    !strings_internal::HasAbslStringify<T>::value,
-                char*>::type = nullptr>
+            typename std::enable_if<std::is_enum<T>{} &&
+                                        !std::is_convertible<T, int>{} &&
+                                        !HasAbslStringify<T>::value,
+                                    char*>::type = nullptr>
   AlphaNum(T e)  // NOLINT(runtime/explicit)
       : AlphaNum(+static_cast<typename std::underlying_type<T>::type>(e)) {}
 
@@ -441,13 +445,48 @@ namespace strings_internal {
 
 // Do not call directly - this is not part of the public API.
 std::string CatPieces(std::initializer_list<absl::string_view> pieces);
-void AppendPieces(std::string* dest,
+void AppendPieces(absl::Nonnull<std::string*> dest,
                   std::initializer_list<absl::string_view> pieces);
 
+void STLStringAppendUninitializedAmortized(std::string* dest, size_t to_append);
+
+// `SingleArgStrCat` overloads take built-in `int`, `long` and `long long` types
+// (signed / unsigned) to avoid ambiguity on the call side. If we used int32_t
+// and int64_t, then at least one of the three (`int` / `long` / `long long`)
+// would have been ambiguous when passed to `SingleArgStrCat`.
+std::string SingleArgStrCat(int x);
+std::string SingleArgStrCat(unsigned int x);
+std::string SingleArgStrCat(long x);                // NOLINT
+std::string SingleArgStrCat(unsigned long x);       // NOLINT
+std::string SingleArgStrCat(long long x);           // NOLINT
+std::string SingleArgStrCat(unsigned long long x);  // NOLINT
+std::string SingleArgStrCat(float x);
+std::string SingleArgStrCat(double x);
+
+// `SingleArgStrAppend` overloads are defined here for the same reasons as with
+// `SingleArgStrCat` above.
+void SingleArgStrAppend(std::string& str, int x);
+void SingleArgStrAppend(std::string& str, unsigned int x);
+void SingleArgStrAppend(std::string& str, long x);                // NOLINT
+void SingleArgStrAppend(std::string& str, unsigned long x);       // NOLINT
+void SingleArgStrAppend(std::string& str, long long x);           // NOLINT
+void SingleArgStrAppend(std::string& str, unsigned long long x);  // NOLINT
+
+template <typename T,
+          typename = std::enable_if_t<std::is_arithmetic<T>::value &&
+                                      !std::is_same<T, char>::value &&
+                                      !std::is_same<T, bool>::value>>
+using EnableIfFastCase = T;
+
 }  // namespace strings_internal
 
 ABSL_MUST_USE_RESULT inline std::string StrCat() { return std::string(); }
 
+template <typename T>
+ABSL_MUST_USE_RESULT inline std::string StrCat(
+    strings_internal::EnableIfFastCase<T> a) {
+  return strings_internal::SingleArgStrCat(a);
+}
 ABSL_MUST_USE_RESULT inline std::string StrCat(const AlphaNum& a) {
   return std::string(a.data(), a.size());
 }
@@ -495,24 +534,87 @@ ABSL_MUST_USE_RESULT inline std::string StrCat(
 //   absl::string_view p = s;
 //   StrAppend(&s, p);
 
-inline void StrAppend(std::string*) {}
-void StrAppend(std::string* dest, const AlphaNum& a);
-void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b);
-void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b,
-               const AlphaNum& c);
-void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b,
-               const AlphaNum& c, const AlphaNum& d);
+inline void StrAppend(absl::Nonnull<std::string*>) {}
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a);
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a,
+               const AlphaNum& b);
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a,
+               const AlphaNum& b, const AlphaNum& c);
+void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a,
+               const AlphaNum& b, const AlphaNum& c, const AlphaNum& d);
 
 // Support 5 or more arguments
 template <typename... AV>
-inline void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b,
-                      const AlphaNum& c, const AlphaNum& d, const AlphaNum& e,
-                      const AV&... args) {
+inline void StrAppend(absl::Nonnull<std::string*> dest, const AlphaNum& a,
+                      const AlphaNum& b, const AlphaNum& c, const AlphaNum& d,
+                      const AlphaNum& e, const AV&... args) {
   strings_internal::AppendPieces(
       dest, {a.Piece(), b.Piece(), c.Piece(), d.Piece(), e.Piece(),
              static_cast<const AlphaNum&>(args).Piece()...});
 }
 
+template <class String, class T>
+std::enable_if_t<
+    std::is_integral<absl::strings_internal::EnableIfFastCase<T>>::value, void>
+StrAppend(absl::Nonnull<String*> result, T i) {
+  return absl::strings_internal::SingleArgStrAppend(*result, i);
+}
+
+// This overload is only selected if all the parameters are numbers that can be
+// handled quickly.
+// Later we can look into how we can extend this to more general argument
+// mixtures without bloating codegen too much, or copying unnecessarily.
+template <typename String, typename... T>
+std::enable_if_t<
+    (sizeof...(T) > 1),
+    std::common_type_t<std::conditional_t<
+        true, void, absl::strings_internal::EnableIfFastCase<T>>...>>
+StrAppend(absl::Nonnull<String*> str, T... args) {
+  // Do not add unnecessary variables, logic, or even "free" lambdas here.
+  // They can add overhead for the compiler and/or at run time.
+  // Furthermore, assume this function will be inlined.
+  // This function is carefully tailored to be able to be largely optimized away
+  // so that it becomes near-equivalent to the caller handling each argument
+  // individually while minimizing register pressure, so that the compiler
+  // can inline it with minimal overhead.
+
+  // First, calculate the total length, so we can perform just a single resize.
+  // Save all the lengths for later.
+  size_t total_length = 0;
+  const ptrdiff_t lengths[] = {
+      absl::numbers_internal::GetNumDigitsOrNegativeIfNegative(args)...};
+  for (const ptrdiff_t possibly_negative_length : lengths) {
+    // Lengths are negative for negative numbers. Keep them for later use, but
+    // take their absolute values for calculating total lengths;
+    total_length += possibly_negative_length < 0
+                        ? static_cast<size_t>(-possibly_negative_length)
+                        : static_cast<size_t>(possibly_negative_length);
+  }
+
+  // Now reserve space for all the arguments.
+  const size_t old_size = str->size();
+  absl::strings_internal::STLStringAppendUninitializedAmortized(str,
+                                                                total_length);
+
+  // Finally, output each argument one-by-one, from left to right.
+  size_t i = 0;  // The current argument we're processing
+  ptrdiff_t n;   // The length of the current argument
+  typename String::pointer pos = &(*str)[old_size];
+  using SomeTrivialEmptyType = std::false_type;
+  // Ugly code due to the lack of C++14 fold expression makes us.
+  const SomeTrivialEmptyType dummy1;
+  for (const SomeTrivialEmptyType& dummy2 :
+       {(/* Comma expressions are poor man's C++17 fold expression for C++14 */
+         (void)(n = lengths[i]),
+         (void)(n < 0 ? (void)(*pos++ = '-'), (n = ~n) : 0),
+         (void)absl::numbers_internal::FastIntToBufferBackward(
+             absl::numbers_internal::UnsignedAbsoluteValue(std::move(args)),
+             pos += n, static_cast<uint32_t>(n)),
+         (void)++i, dummy1)...}) {
+    (void)dummy2;  // Remove & migrate to fold expressions in C++17
+  }
+}
+
 // Helper function for the future StrCat default floating-point format, %.6g
 // This is fast.
 inline strings_internal::AlphaNumBuffer<
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_format.h b/contrib/restricted/abseil-cpp/absl/strings/str_format.h
index 023e4350d3..66b6af5854 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_format.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_format.h
@@ -72,14 +72,21 @@
 #ifndef ABSL_STRINGS_STR_FORMAT_H_
 #define ABSL_STRINGS_STR_FORMAT_H_
 
+#include <cstdint>
 #include <cstdio>
 #include <string>
+#include <type_traits>
 
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/internal/str_format/arg.h"  // IWYU pragma: export
 #include "absl/strings/internal/str_format/bind.h"  // IWYU pragma: export
 #include "absl/strings/internal/str_format/checker.h"  // IWYU pragma: export
 #include "absl/strings/internal/str_format/extension.h"  // IWYU pragma: export
 #include "absl/strings/internal/str_format/parser.h"  // IWYU pragma: export
+#include "absl/strings/string_view.h"
+#include "absl/types/span.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -104,7 +111,8 @@ class UntypedFormatSpec {
   explicit UntypedFormatSpec(string_view s) : spec_(s) {}
 
  protected:
-  explicit UntypedFormatSpec(const str_format_internal::ParsedFormatBase* pc)
+  explicit UntypedFormatSpec(
+      absl::Nonnull<const str_format_internal::ParsedFormatBase*> pc)
       : spec_(pc) {}
 
  private:
@@ -144,7 +152,7 @@ str_format_internal::StreamedWrapper<T> FormatStreamed(const T& v) {
 //   EXPECT_EQ(8, n);
 class FormatCountCapture {
  public:
-  explicit FormatCountCapture(int* p) : p_(p) {}
+  explicit FormatCountCapture(absl::Nonnull<int*> p) : p_(p) {}
 
  private:
   // FormatCountCaptureHelper is used to define FormatConvertImpl() for this
@@ -153,8 +161,8 @@ class FormatCountCapture {
   // Unused() is here because of the false positive from -Wunused-private-field
   // p_ is used in the templated function of the friend FormatCountCaptureHelper
   // class.
-  int* Unused() { return p_; }
-  int* p_;
+  absl::Nonnull<int*> Unused() { return p_; }
+  absl::Nonnull<int*> p_;
 };
 
 // FormatSpec
@@ -250,13 +258,13 @@ class FormatCountCapture {
 // `v` uses `d` for signed integer values, `u` for unsigned integer values, `g`
 // for floating point values, and formats boolean values as "true"/"false"
 // (instead of 1 or 0 for booleans formatted using d). `const char*` is not
-// supported; please use `std:string` and `string_view`. `char` is also not
+// supported; please use `std::string` and `string_view`. `char` is also not
 // supported due to ambiguity of the type. This specifier does not support
 // modifiers.
 //
 // The `FormatSpec` intrinsically supports all of these fundamental C++ types:
 //
-// *   Characters: `char`, `signed char`, `unsigned char`
+// *   Characters: `char`, `signed char`, `unsigned char`, `wchar_t`
 // *   Integers: `int`, `short`, `unsigned short`, `unsigned`, `long`,
 //         `unsigned long`, `long long`, `unsigned long long`
 // *   Enums: printed as their underlying integral value
@@ -264,9 +272,9 @@ class FormatCountCapture {
 //
 // However, in the `str_format` library, a format conversion specifies a broader
 // C++ conceptual category instead of an exact type. For example, `%s` binds to
-// any string-like argument, so `std::string`, `absl::string_view`, and
-// `const char*` are all accepted. Likewise, `%d` accepts any integer-like
-// argument, etc.
+// any string-like argument, so `std::string`, `std::wstring`,
+// `absl::string_view`, `const char*`, and `const wchar_t*` are all accepted.
+// Likewise, `%d` accepts any integer-like argument, etc.
 
 template <typename... Args>
 using FormatSpec = str_format_internal::FormatSpecTemplate<
@@ -287,8 +295,8 @@ using FormatSpec = str_format_internal::FormatSpecTemplate<
 // Example:
 //
 //   // Verified at compile time.
-//   absl::ParsedFormat<'s', 'd'> formatString("Welcome to %s, Number %d!");
-//   absl::StrFormat(formatString, "TheVillage", 6);
+//   absl::ParsedFormat<'s', 'd'> format_string("Welcome to %s, Number %d!");
+//   absl::StrFormat(format_string, "TheVillage", 6);
 //
 //   // Verified at runtime.
 //   auto format_runtime = absl::ParsedFormat<'d'>::New(format_string);
@@ -369,7 +377,7 @@ ABSL_MUST_USE_RESULT std::string StrFormat(const FormatSpec<Args...>& format,
 //   std::string orig("For example PI is approximately ");
 //   std::cout << StrAppendFormat(&orig, "%12.6f", 3.14);
 template <typename... Args>
-std::string& StrAppendFormat(std::string* dst,
+std::string& StrAppendFormat(absl::Nonnull<std::string*> dst,
                              const FormatSpec<Args...>& format,
                              const Args&... args) {
   return str_format_internal::AppendPack(
@@ -381,7 +389,7 @@ std::string& StrAppendFormat(std::string* dst,
 //
 // Writes to an output stream given a format string and zero or more arguments,
 // generally in a manner that is more efficient than streaming the result of
-// `absl:: StrFormat()`. The returned object must be streamed before the full
+// `absl::StrFormat()`. The returned object must be streamed before the full
 // expression ends.
 //
 // Example:
@@ -429,7 +437,7 @@ int PrintF(const FormatSpec<Args...>& format, const Args&... args) {
 //   Outputs: "The capital of Mongolia is Ulaanbaatar"
 //
 template <typename... Args>
-int FPrintF(std::FILE* output, const FormatSpec<Args...>& format,
+int FPrintF(absl::Nonnull<std::FILE*> output, const FormatSpec<Args...>& format,
             const Args&... args) {
   return str_format_internal::FprintF(
       output, str_format_internal::UntypedFormatSpecImpl::Extract(format),
@@ -458,8 +466,8 @@ int FPrintF(std::FILE* output, const FormatSpec<Args...>& format,
 //   Post-condition: output == "The capital of Mongolia is Ulaanbaatar"
 //
 template <typename... Args>
-int SNPrintF(char* output, std::size_t size, const FormatSpec<Args...>& format,
-             const Args&... args) {
+int SNPrintF(absl::Nonnull<char*> output, std::size_t size,
+             const FormatSpec<Args...>& format, const Args&... args) {
   return str_format_internal::SnprintF(
       output, size, str_format_internal::UntypedFormatSpecImpl::Extract(format),
       {str_format_internal::FormatArgImpl(args)...});
@@ -492,7 +500,7 @@ class FormatRawSink {
   template <typename T,
             typename = typename std::enable_if<std::is_constructible<
                 str_format_internal::FormatRawSinkImpl, T*>::value>::type>
-  FormatRawSink(T* raw)  // NOLINT
+  FormatRawSink(absl::Nonnull<T*> raw)  // NOLINT
       : sink_(raw) {}
 
  private:
@@ -849,14 +857,16 @@ class FormatSink {
   }
 
   // Support `absl::Format(&sink, format, args...)`.
-  friend void AbslFormatFlush(FormatSink* sink, absl::string_view v) {
+  friend void AbslFormatFlush(absl::Nonnull<FormatSink*> sink,
+                              absl::string_view v) {
     sink->Append(v);
   }
 
  private:
   friend str_format_internal::FormatSinkImpl;
-  explicit FormatSink(str_format_internal::FormatSinkImpl* s) : sink_(s) {}
-  str_format_internal::FormatSinkImpl* sink_;
+  explicit FormatSink(absl::Nonnull<str_format_internal::FormatSinkImpl*> s)
+      : sink_(s) {}
+  absl::Nonnull<str_format_internal::FormatSinkImpl*> sink_;
 };
 
 // FormatConvertResult
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_join.h b/contrib/restricted/abseil-cpp/absl/strings/str_join.h
index ee5ae7efdf..6a92c0f53a 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_join.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_join.h
@@ -80,7 +80,7 @@ ABSL_NAMESPACE_BEGIN
 //       absl::StrJoin(v, ", ", [](std::string* out, absl::Duration dur) {
 //         absl::StrAppend(out, absl::FormatDuration(dur));
 //       });
-//   EXPECT_EQ("1s, 10ms", s);
+//   EXPECT_EQ(s, "1s, 10ms");
 //
 // The following standard formatters are provided within this file:
 //
@@ -164,21 +164,21 @@ DereferenceFormatter() {
 //   // of `absl::string_view` or even `const char*`.
 //   std::vector<std::string> v = {"foo", "bar", "baz"};
 //   std::string s = absl::StrJoin(v, "-");
-//   EXPECT_EQ("foo-bar-baz", s);
+//   EXPECT_EQ(s, "foo-bar-baz");
 //
 // Example 2:
 //   // Joins the values in the given `std::initializer_list<>` specified using
 //   // brace initialization. This pattern also works with an initializer_list
 //   // of ints or `absl::string_view` -- any `AlphaNum`-compatible type.
 //   std::string s = absl::StrJoin({"foo", "bar", "baz"}, "-");
-//   EXPECT_EQ("foo-bar-baz", s);
+//   EXPECT_EQs, "foo-bar-baz");
 //
 // Example 3:
 //   // Joins a collection of ints. This pattern also works with floats,
 //   // doubles, int64s -- any `StrCat()`-compatible type.
 //   std::vector<int> v = {1, 2, 3, -4};
 //   std::string s = absl::StrJoin(v, "-");
-//   EXPECT_EQ("1-2-3--4", s);
+//   EXPECT_EQ(s, "1-2-3--4");
 //
 // Example 4:
 //   // Joins a collection of pointer-to-int. By default, pointers are
@@ -189,7 +189,7 @@ DereferenceFormatter() {
 //   int x = 1, y = 2, z = 3;
 //   std::vector<int*> v = {&x, &y, &z};
 //   std::string s = absl::StrJoin(v, "-");
-//   EXPECT_EQ("1-2-3", s);
+//   EXPECT_EQ(s, "1-2-3");
 //
 // Example 5:
 //   // Dereferencing of `std::unique_ptr<>` is also supported:
@@ -198,42 +198,42 @@ DereferenceFormatter() {
 //   v.emplace_back(new int(2));
 //   v.emplace_back(new int(3));
 //   std::string s = absl::StrJoin(v, "-");
-//   EXPECT_EQ("1-2-3", s);
+//   EXPECT_EQ(s, "1-2-3");
 //
 // Example 6:
 //   // Joins a `std::map`, with each key-value pair separated by an equals
 //   // sign. This pattern would also work with, say, a
 //   // `std::vector<std::pair<>>`.
 //   std::map<std::string, int> m = {
-//       std::make_pair("a", 1),
-//       std::make_pair("b", 2),
-//       std::make_pair("c", 3)};
+//       {"a", 1},
+//       {"b", 2},
+//       {"c", 3}};
 //   std::string s = absl::StrJoin(m, ",", absl::PairFormatter("="));
-//   EXPECT_EQ("a=1,b=2,c=3", s);
+//   EXPECT_EQ(s, "a=1,b=2,c=3");
 //
 // Example 7:
 //   // These examples show how `absl::StrJoin()` handles a few common edge
 //   // cases:
 //   std::vector<std::string> v_empty;
-//   EXPECT_EQ("", absl::StrJoin(v_empty, "-"));
+//   EXPECT_EQ(absl::StrJoin(v_empty, "-"), "");
 //
 //   std::vector<std::string> v_one_item = {"foo"};
-//   EXPECT_EQ("foo", absl::StrJoin(v_one_item, "-"));
+//   EXPECT_EQ(absl::StrJoin(v_one_item, "-"), "foo");
 //
 //   std::vector<std::string> v_empty_string = {""};
-//   EXPECT_EQ("", absl::StrJoin(v_empty_string, "-"));
+//   EXPECT_EQ(absl::StrJoin(v_empty_string, "-"), "");
 //
 //   std::vector<std::string> v_one_item_empty_string = {"a", ""};
-//   EXPECT_EQ("a-", absl::StrJoin(v_one_item_empty_string, "-"));
+//   EXPECT_EQ(absl::StrJoin(v_one_item_empty_string, "-"), "a-");
 //
 //   std::vector<std::string> v_two_empty_string = {"", ""};
-//   EXPECT_EQ("-", absl::StrJoin(v_two_empty_string, "-"));
+//   EXPECT_EQ(absl::StrJoin(v_two_empty_string, "-"), "-");
 //
 // Example 8:
 //   // Joins a `std::tuple<T...>` of heterogeneous types, converting each to
 //   // a std::string using the `absl::AlphaNum` class.
 //   std::string s = absl::StrJoin(std::make_tuple(123, "abc", 0.456), "-");
-//   EXPECT_EQ("123-abc-0.456", s);
+//   EXPECT_EQ(s, "123-abc-0.456");
 
 template <typename Iterator, typename Formatter>
 std::string StrJoin(Iterator start, Iterator end, absl::string_view sep,
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_replace.cc b/contrib/restricted/abseil-cpp/absl/strings/str_replace.cc
index 2bd5fa9821..a7ab52fed5 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_replace.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_replace.cc
@@ -14,7 +14,16 @@
 
 #include "absl/strings/str_replace.h"
 
+#include <cstddef>
+#include <initializer_list>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "absl/base/config.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/str_cat.h"
+#include "absl/strings/string_view.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -28,8 +37,8 @@ using FixedMapping =
 // occurred.
 int ApplySubstitutions(
     absl::string_view s,
-    std::vector<strings_internal::ViableSubstitution>* subs_ptr,
-    std::string* result_ptr) {
+    absl::Nonnull<std::vector<strings_internal::ViableSubstitution>*> subs_ptr,
+    absl::Nonnull<std::string*> result_ptr) {
   auto& subs = *subs_ptr;
   int substitutions = 0;
   size_t pos = 0;
@@ -74,7 +83,7 @@ std::string StrReplaceAll(absl::string_view s,
 }
 
 int StrReplaceAll(strings_internal::FixedMapping replacements,
-                  std::string* target) {
+                  absl::Nonnull<std::string*> target) {
   return StrReplaceAll<strings_internal::FixedMapping>(replacements, target);
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_replace.h b/contrib/restricted/abseil-cpp/absl/strings/str_replace.h
index 273c707735..e77ced3e57 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_replace.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_replace.h
@@ -43,6 +43,7 @@
 #include <vector>
 
 #include "absl/base/attributes.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/string_view.h"
 
 namespace absl {
@@ -113,7 +114,7 @@ std::string StrReplaceAll(absl::string_view s,
 int StrReplaceAll(
     std::initializer_list<std::pair<absl::string_view, absl::string_view>>
         replacements,
-    std::string* target);
+    absl::Nonnull<std::string*> target);
 
 // Overload of `StrReplaceAll()` to replace patterns within a given output
 // string *in place* with replacements provided within a container of key/value
@@ -128,7 +129,8 @@ int StrReplaceAll(
 //  EXPECT_EQ(count, 2);
 //  EXPECT_EQ("if (ptr &lt; &amp;foo)", s);
 template <typename StrToStrMapping>
-int StrReplaceAll(const StrToStrMapping& replacements, std::string* target);
+int StrReplaceAll(const StrToStrMapping& replacements,
+                  absl::Nonnull<std::string*> target);
 
 // Implementation details only, past this point.
 namespace strings_internal {
@@ -185,8 +187,8 @@ std::vector<ViableSubstitution> FindSubstitutions(
 }
 
 int ApplySubstitutions(absl::string_view s,
-                       std::vector<ViableSubstitution>* subs_ptr,
-                       std::string* result_ptr);
+                       absl::Nonnull<std::vector<ViableSubstitution>*> subs_ptr,
+                       absl::Nonnull<std::string*> result_ptr);
 
 }  // namespace strings_internal
 
@@ -201,7 +203,8 @@ std::string StrReplaceAll(absl::string_view s,
 }
 
 template <typename StrToStrMapping>
-int StrReplaceAll(const StrToStrMapping& replacements, std::string* target) {
+int StrReplaceAll(const StrToStrMapping& replacements,
+                  absl::Nonnull<std::string*> target) {
   auto subs = strings_internal::FindSubstitutions(*target, replacements);
   if (subs.empty()) return 0;
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_split.cc b/contrib/restricted/abseil-cpp/absl/strings/str_split.cc
index 72ba7c02df..abe486b915 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_split.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_split.cc
@@ -15,16 +15,13 @@
 #include "absl/strings/str_split.h"
 
 #include <algorithm>
-#include <cassert>
-#include <cstdint>
+#include <cstddef>
 #include <cstdlib>
 #include <cstring>
-#include <iterator>
-#include <limits>
-#include <memory>
 
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
-#include "absl/strings/ascii.h"
+#include "absl/strings/string_view.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
@@ -99,6 +96,11 @@ absl::string_view ByString::Find(absl::string_view text, size_t pos) const {
   return GenericFind(text, delimiter_, pos, LiteralPolicy());
 }
 
+absl::string_view ByAsciiWhitespace::Find(absl::string_view text,
+                                          size_t pos) const {
+  return GenericFind(text, " \t\v\f\r\n", pos, AnyOfPolicy());
+}
+
 //
 // ByChar
 //
diff --git a/contrib/restricted/abseil-cpp/absl/strings/str_split.h b/contrib/restricted/abseil-cpp/absl/strings/str_split.h
index 7bbb68a343..87540278ad 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/str_split.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/str_split.h
@@ -130,6 +130,24 @@ class ByString {
   const std::string delimiter_;
 };
 
+// ByAsciiWhitespace
+//
+// A sub-string delimiter that splits by ASCII whitespace
+// (space, tab, vertical tab, formfeed, linefeed, or carriage return).
+// Note: you probably want to use absl::SkipEmpty() as well!
+//
+// This class is equivalent to ByAnyChar with ASCII whitespace chars.
+//
+// Example:
+//
+//   std::vector<std::string> v = absl::StrSplit(
+//       "a b\tc\n  d  \n", absl::ByAsciiWhitespace(), absl::SkipEmpty());
+//   // v[0] == "a", v[1] == "b", v[2] == "c", v[3] == "d"
+class ByAsciiWhitespace {
+ public:
+  absl::string_view Find(absl::string_view text, size_t pos) const;
+};
+
 // ByChar
 //
 // A single character delimiter. `ByChar` is functionally equivalent to a
diff --git a/contrib/restricted/abseil-cpp/absl/strings/string_view.cc b/contrib/restricted/abseil-cpp/absl/strings/string_view.cc
index f20ff5306e..97025c32a5 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/string_view.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/string_view.cc
@@ -21,6 +21,8 @@
 #include <cstring>
 #include <ostream>
 
+#include "absl/base/nullability.h"
+
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
@@ -28,8 +30,10 @@ namespace {
 
 // This is significantly faster for case-sensitive matches with very
 // few possible matches.
-const char* memmatch(const char* phaystack, size_t haylen, const char* pneedle,
-                     size_t neelen) {
+absl::Nullable<const char*> memmatch(absl::Nullable<const char*> phaystack,
+                                     size_t haylen,
+                                     absl::Nullable<const char*> pneedle,
+                                     size_t neelen) {
   if (0 == neelen) {
     return phaystack;  // even if haylen is 0
   }
@@ -37,8 +41,8 @@ const char* memmatch(const char* phaystack, size_t haylen, const char* pneedle,
 
   const char* match;
   const char* hayend = phaystack + haylen - neelen + 1;
-  // A static cast is used here to work around the fact that memchr returns
-  // a void* on Posix-compliant systems and const void* on Windows.
+  // A static cast is used here as memchr returns a const void *, and pointer
+  // arithmetic is not allowed on pointers to void.
   while (
       (match = static_cast<const char*>(memchr(
            phaystack, pneedle[0], static_cast<size_t>(hayend - phaystack))))) {
@@ -229,7 +233,6 @@ string_view::size_type string_view::find_last_not_of(
   return npos;
 }
 
-
 #ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
 constexpr string_view::size_type string_view::npos;
 constexpr string_view::size_type string_view::kMaxSize;
@@ -238,4 +241,22 @@ constexpr string_view::size_type string_view::kMaxSize;
 ABSL_NAMESPACE_END
 }  // namespace absl
 
+#else
+
+// https://github.com/abseil/abseil-cpp/issues/1465
+// CMake builds on Apple platforms error when libraries are empty.
+// Our CMake configuration can avoid this error on header-only libraries,
+// but since this library is conditionally empty, including a single
+// variable is an easy workaround.
+#ifdef __APPLE__
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace strings_internal {
+extern const char kAvoidEmptyStringViewLibraryWarning;
+const char kAvoidEmptyStringViewLibraryWarning = 0;
+}  // namespace strings_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
+#endif  // __APPLE__
+
 #endif  // ABSL_USES_STD_STRING_VIEW
diff --git a/contrib/restricted/abseil-cpp/absl/strings/string_view.h b/contrib/restricted/abseil-cpp/absl/strings/string_view.h
index eae11b2ab6..04ca0a38ae 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/string_view.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/string_view.h
@@ -37,6 +37,7 @@
 #include <string>
 
 #include "absl/base/attributes.h"
+#include "absl/base/nullability.h"
 #include "absl/base/config.h"
 #include "absl/base/internal/throw_delegate.h"
 #include "absl/base/macros.h"
@@ -162,11 +163,11 @@ class string_view {
  public:
   using traits_type = std::char_traits<char>;
   using value_type = char;
-  using pointer = char*;
-  using const_pointer = const char*;
+  using pointer = absl::Nullable<char*>;
+  using const_pointer = absl::Nullable<const char*>;
   using reference = char&;
   using const_reference = const char&;
-  using const_iterator = const char*;
+  using const_iterator = absl::Nullable<const char*>;
   using iterator = const_iterator;
   using const_reverse_iterator = std::reverse_iterator<const_iterator>;
   using reverse_iterator = const_reverse_iterator;
@@ -194,11 +195,12 @@ class string_view {
   // accepting possibly null strings, use `absl::NullSafeStringView(str)`
   // instead (see below).
   // The length check is skipped since it is unnecessary and causes code bloat.
-  constexpr string_view(const char* str)  // NOLINT(runtime/explicit)
+  constexpr string_view(  // NOLINT(runtime/explicit)
+      absl::Nonnull<const char*> str)
       : ptr_(str), length_(str ? StrlenInternal(str) : 0) {}
 
   // Implicit constructor of a `string_view` from a `const char*` and length.
-  constexpr string_view(const char* data, size_type len)
+  constexpr string_view(absl::Nullable<const char*> data, size_type len)
       : ptr_(data), length_(CheckLengthInternal(len)) {}
 
   // NOTE: Harmlessly omitted to work around gdb bug.
@@ -427,18 +429,21 @@ class string_view {
 
   // Overload of `string_view::compare()` for comparing a `string_view` and a
   // a different C-style string `s`.
-  constexpr int compare(const char* s) const { return compare(string_view(s)); }
+  constexpr int compare(absl::Nonnull<const char*> s) const {
+    return compare(string_view(s));
+  }
 
   // Overload of `string_view::compare()` for comparing a substring of the
   // `string_view` and a different string C-style string `s`.
-  constexpr int compare(size_type pos1, size_type count1, const char* s) const {
+  constexpr int compare(size_type pos1, size_type count1,
+                        absl::Nonnull<const char*> s) const {
     return substr(pos1, count1).compare(string_view(s));
   }
 
   // Overload of `string_view::compare()` for comparing a substring of the
   // `string_view` and a substring of a different C-style string `s`.
-  constexpr int compare(size_type pos1, size_type count1, const char* s,
-                        size_type count2) const {
+  constexpr int compare(size_type pos1, size_type count1,
+                        absl::Nonnull<const char*> s, size_type count2) const {
     return substr(pos1, count1).compare(string_view(s, count2));
   }
 
@@ -457,13 +462,14 @@ class string_view {
 
   // Overload of `string_view::find()` for finding a substring of a different
   // C-style string `s` within the `string_view`.
-  size_type find(const char* s, size_type pos, size_type count) const {
+  size_type find(absl::Nonnull<const char*> s, size_type pos,
+                 size_type count) const {
     return find(string_view(s, count), pos);
   }
 
   // Overload of `string_view::find()` for finding a different C-style string
   // `s` within the `string_view`.
-  size_type find(const char* s, size_type pos = 0) const {
+  size_type find(absl::Nonnull<const char *> s, size_type pos = 0) const {
     return find(string_view(s), pos);
   }
 
@@ -480,13 +486,14 @@ class string_view {
 
   // Overload of `string_view::rfind()` for finding a substring of a different
   // C-style string `s` within the `string_view`.
-  size_type rfind(const char* s, size_type pos, size_type count) const {
+  size_type rfind(absl::Nonnull<const char*> s, size_type pos,
+                  size_type count) const {
     return rfind(string_view(s, count), pos);
   }
 
   // Overload of `string_view::rfind()` for finding a different C-style string
   // `s` within the `string_view`.
-  size_type rfind(const char* s, size_type pos = npos) const {
+  size_type rfind(absl::Nonnull<const char*> s, size_type pos = npos) const {
     return rfind(string_view(s), pos);
   }
 
@@ -505,14 +512,15 @@ class string_view {
 
   // Overload of `string_view::find_first_of()` for finding a substring of a
   // different C-style string `s` within the `string_view`.
-  size_type find_first_of(const char* s, size_type pos,
-                                    size_type count) const {
+  size_type find_first_of(absl::Nonnull<const char*> s, size_type pos,
+                          size_type count) const {
     return find_first_of(string_view(s, count), pos);
   }
 
   // Overload of `string_view::find_first_of()` for finding a different C-style
   // string `s` within the `string_view`.
-  size_type find_first_of(const char* s, size_type pos = 0) const {
+  size_type find_first_of(absl::Nonnull<const char*> s,
+                          size_type pos = 0) const {
     return find_first_of(string_view(s), pos);
   }
 
@@ -531,13 +539,15 @@ class string_view {
 
   // Overload of `string_view::find_last_of()` for finding a substring of a
   // different C-style string `s` within the `string_view`.
-  size_type find_last_of(const char* s, size_type pos, size_type count) const {
+  size_type find_last_of(absl::Nonnull<const char*> s, size_type pos,
+                         size_type count) const {
     return find_last_of(string_view(s, count), pos);
   }
 
   // Overload of `string_view::find_last_of()` for finding a different C-style
   // string `s` within the `string_view`.
-  size_type find_last_of(const char* s, size_type pos = npos) const {
+  size_type find_last_of(absl::Nonnull<const char*> s,
+                         size_type pos = npos) const {
     return find_last_of(string_view(s), pos);
   }
 
@@ -554,14 +564,15 @@ class string_view {
 
   // Overload of `string_view::find_first_not_of()` for finding a substring of a
   // different C-style string `s` within the `string_view`.
-  size_type find_first_not_of(const char* s, size_type pos,
+  size_type find_first_not_of(absl::Nonnull<const char*> s, size_type pos,
                               size_type count) const {
     return find_first_not_of(string_view(s, count), pos);
   }
 
   // Overload of `string_view::find_first_not_of()` for finding a different
   // C-style string `s` within the `string_view`.
-  size_type find_first_not_of(const char* s, size_type pos = 0) const {
+  size_type find_first_not_of(absl::Nonnull<const char*> s,
+                              size_type pos = 0) const {
     return find_first_not_of(string_view(s), pos);
   }
 
@@ -579,22 +590,76 @@ class string_view {
 
   // Overload of `string_view::find_last_not_of()` for finding a substring of a
   // different C-style string `s` within the `string_view`.
-  size_type find_last_not_of(const char* s, size_type pos,
+  size_type find_last_not_of(absl::Nonnull<const char*> s, size_type pos,
                              size_type count) const {
     return find_last_not_of(string_view(s, count), pos);
   }
 
   // Overload of `string_view::find_last_not_of()` for finding a different
   // C-style string `s` within the `string_view`.
-  size_type find_last_not_of(const char* s, size_type pos = npos) const {
+  size_type find_last_not_of(absl::Nonnull<const char*> s,
+                             size_type pos = npos) const {
     return find_last_not_of(string_view(s), pos);
   }
 
+#if ABSL_INTERNAL_CPLUSPLUS_LANG >= 202002L
+  // string_view::starts_with()
+  //
+  // Returns true if the `string_view` starts with the prefix `s`.
+  //
+  // This method only exists when targeting at least C++20.
+  // If support for C++ prior to C++20 is required, use `absl::StartsWith()`
+  // from `//absl/strings/match.h` for compatibility.
+  constexpr bool starts_with(string_view s) const noexcept {
+    return s.empty() ||
+           (size() >= s.size() &&
+            ABSL_INTERNAL_STRING_VIEW_MEMCMP(data(), s.data(), s.size()) == 0);
+  }
+
+  // Overload of `string_view::starts_with()` that returns true if `c` is the
+  // first character of the `string_view`.
+  constexpr bool starts_with(char c) const noexcept {
+    return !empty() && front() == c;
+  }
+
+  // Overload of `string_view::starts_with()` that returns true if the
+  // `string_view` starts with the C-style prefix `s`.
+  constexpr bool starts_with(const char* s) const {
+    return starts_with(string_view(s));
+  }
+
+  // string_view::ends_with()
+  //
+  // Returns true if the `string_view` ends with the suffix `s`.
+  //
+  // This method only exists when targeting at least C++20.
+  // If support for C++ prior to C++20 is required, use `absl::EndsWith()`
+  // from `//absl/strings/match.h` for compatibility.
+  constexpr bool ends_with(string_view s) const noexcept {
+    return s.empty() || (size() >= s.size() && ABSL_INTERNAL_STRING_VIEW_MEMCMP(
+                                                   data() + (size() - s.size()),
+                                                   s.data(), s.size()) == 0);
+  }
+
+  // Overload of `string_view::ends_with()` that returns true if `c` is the
+  // last character of the `string_view`.
+  constexpr bool ends_with(char c) const noexcept {
+    return !empty() && back() == c;
+  }
+
+  // Overload of `string_view::ends_with()` that returns true if the
+  // `string_view` ends with the C-style suffix `s`.
+  constexpr bool ends_with(const char* s) const {
+    return ends_with(string_view(s));
+  }
+#endif  // ABSL_INTERNAL_CPLUSPLUS_LANG >= 202002L
+
  private:
   // The constructor from std::string delegates to this constructor.
   // See the comment on that constructor for the rationale.
   struct SkipCheckLengthTag {};
-  string_view(const char* data, size_type len, SkipCheckLengthTag) noexcept
+  string_view(absl::Nullable<const char*> data, size_type len,
+              SkipCheckLengthTag) noexcept
       : ptr_(data), length_(len) {}
 
   static constexpr size_type kMaxSize =
@@ -604,7 +669,7 @@ class string_view {
     return ABSL_HARDENING_ASSERT(len <= kMaxSize), len;
   }
 
-  static constexpr size_type StrlenInternal(const char* str) {
+  static constexpr size_type StrlenInternal(absl::Nonnull<const char*> str) {
 #if defined(_MSC_VER) && _MSC_VER >= 1910 && !defined(__clang__)
     // MSVC 2017+ can evaluate this at compile-time.
     const char* begin = str;
@@ -633,7 +698,7 @@ class string_view {
                                : (compare_result < 0 ? -1 : 1);
   }
 
-  const char* ptr_;
+  absl::Nullable<const char*> ptr_;
   size_type length_;
 };
 
@@ -694,7 +759,7 @@ inline string_view ClippedSubstr(string_view s, size_t pos,
 // Creates an `absl::string_view` from a pointer `p` even if it's null-valued.
 // This function should be used where an `absl::string_view` can be created from
 // a possibly-null pointer.
-constexpr string_view NullSafeStringView(const char* p) {
+constexpr string_view NullSafeStringView(absl::Nullable<const char*> p) {
   return p ? string_view(p) : string_view();
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/strings/strip.h b/contrib/restricted/abseil-cpp/absl/strings/strip.h
index 341e66fc92..e3cda5bac3 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/strip.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/strip.h
@@ -25,6 +25,7 @@
 #include <string>
 
 #include "absl/base/macros.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/match.h"
 #include "absl/strings/string_view.h"
@@ -43,7 +44,8 @@ ABSL_NAMESPACE_BEGIN
 //   absl::string_view input("abc");
 //   EXPECT_TRUE(absl::ConsumePrefix(&input, "a"));
 //   EXPECT_EQ(input, "bc");
-inline bool ConsumePrefix(absl::string_view* str, absl::string_view expected) {
+inline bool ConsumePrefix(absl::Nonnull<absl::string_view*> str,
+                          absl::string_view expected) {
   if (!absl::StartsWith(*str, expected)) return false;
   str->remove_prefix(expected.size());
   return true;
@@ -59,7 +61,8 @@ inline bool ConsumePrefix(absl::string_view* str, absl::string_view expected) {
 //   absl::string_view input("abcdef");
 //   EXPECT_TRUE(absl::ConsumeSuffix(&input, "def"));
 //   EXPECT_EQ(input, "abc");
-inline bool ConsumeSuffix(absl::string_view* str, absl::string_view expected) {
+inline bool ConsumeSuffix(absl::Nonnull<absl::string_view*> str,
+                          absl::string_view expected) {
   if (!absl::EndsWith(*str, expected)) return false;
   str->remove_suffix(expected.size());
   return true;
diff --git a/contrib/restricted/abseil-cpp/absl/strings/substitute.cc b/contrib/restricted/abseil-cpp/absl/strings/substitute.cc
index 33a39305db..dd32c75f69 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/substitute.cc
+++ b/contrib/restricted/abseil-cpp/absl/strings/substitute.cc
@@ -15,20 +15,28 @@
 #include "absl/strings/substitute.h"
 
 #include <algorithm>
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <string>
 
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
+#include "absl/base/nullability.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/escaping.h"
 #include "absl/strings/internal/resize_uninitialized.h"
+#include "absl/strings/numbers.h"
+#include "absl/strings/str_cat.h"
 #include "absl/strings/string_view.h"
 
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace substitute_internal {
 
-void SubstituteAndAppendArray(std::string* output, absl::string_view format,
-                              const absl::string_view* args_array,
-                              size_t num_args) {
+void SubstituteAndAppendArray(
+    absl::Nonnull<std::string*> output, absl::string_view format,
+    absl::Nullable<const absl::string_view*> args_array, size_t num_args) {
   // Determine total size needed.
   size_t size = 0;
   for (size_t i = 0; i < format.size(); i++) {
@@ -97,7 +105,7 @@ void SubstituteAndAppendArray(std::string* output, absl::string_view format,
   assert(target == output->data() + output->size());
 }
 
-Arg::Arg(const void* value) {
+Arg::Arg(absl::Nullable<const void*> value) {
   static_assert(sizeof(scratch_) >= sizeof(value) * 2 + 2,
                 "fix sizeof(scratch_)");
   if (value == nullptr) {
diff --git a/contrib/restricted/abseil-cpp/absl/strings/substitute.h b/contrib/restricted/abseil-cpp/absl/strings/substitute.h
index d6a5a690d7..6c7cba4be5 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/substitute.h
+++ b/contrib/restricted/abseil-cpp/absl/strings/substitute.h
@@ -78,6 +78,7 @@
 #include <vector>
 
 #include "absl/base/macros.h"
+#include "absl/base/nullability.h"
 #include "absl/base/port.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/escaping.h"
@@ -105,7 +106,7 @@ class Arg {
   // Overloads for string-y things
   //
   // Explicitly overload `const char*` so the compiler doesn't cast to `bool`.
-  Arg(const char* value)  // NOLINT(google-explicit-constructor)
+  Arg(absl::Nullable<const char*> value)  // NOLINT(google-explicit-constructor)
       : piece_(absl::NullSafeStringView(value)) {}
   template <typename Allocator>
   Arg(  // NOLINT
@@ -176,7 +177,7 @@ class Arg {
       : piece_(value ? "true" : "false") {}
 
   template <typename T, typename = typename std::enable_if<
-                            strings_internal::HasAbslStringify<T>::value>::type>
+                            HasAbslStringify<T>::value>::type>
   Arg(  // NOLINT(google-explicit-constructor)
       const T& v, strings_internal::StringifySink&& sink = {})
       : piece_(strings_internal::ExtractStringification(sink, v)) {}
@@ -197,14 +198,15 @@ class Arg {
 
   // `void*` values, with the exception of `char*`, are printed as
   // "0x<hex value>". However, in the case of `nullptr`, "NULL" is printed.
-  Arg(const void* value);  // NOLINT(google-explicit-constructor)
+  Arg(  // NOLINT(google-explicit-constructor)
+      absl::Nullable<const void*> value);
 
   // Normal enums are already handled by the integer formatters.
   // This overload matches only scoped enums.
   template <typename T,
             typename = typename std::enable_if<
                 std::is_enum<T>{} && !std::is_convertible<T, int>{} &&
-                !strings_internal::HasAbslStringify<T>::value>::type>
+                !HasAbslStringify<T>::value>::type>
   Arg(T value)  // NOLINT(google-explicit-constructor)
       : Arg(static_cast<typename std::underlying_type<T>::type>(value)) {}
 
@@ -220,12 +222,12 @@ class Arg {
 
 // Internal helper function. Don't call this from outside this implementation.
 // This interface may change without notice.
-void SubstituteAndAppendArray(std::string* output, absl::string_view format,
-                              const absl::string_view* args_array,
-                              size_t num_args);
+void SubstituteAndAppendArray(
+    absl::Nonnull<std::string*> output, absl::string_view format,
+    absl::Nullable<const absl::string_view*> args_array, size_t num_args);
 
 #if defined(ABSL_BAD_CALL_IF)
-constexpr int CalculateOneBit(const char* format) {
+constexpr int CalculateOneBit(absl::Nonnull<const char*> format) {
   // Returns:
   // * 2^N for '$N' when N is in [0-9]
   // * 0 for correct '$' escaping: '$$'.
@@ -234,11 +236,11 @@ constexpr int CalculateOneBit(const char* format) {
                                           : (1 << (*format - '0'));
 }
 
-constexpr const char* SkipNumber(const char* format) {
+constexpr const char* SkipNumber(absl::Nonnull<const char*> format) {
   return !*format ? format : (format + 1);
 }
 
-constexpr int PlaceholderBitmask(const char* format) {
+constexpr int PlaceholderBitmask(absl::Nonnull<const char*> format) {
   return !*format
              ? 0
              : *format != '$' ? PlaceholderBitmask(format + 1)
@@ -271,18 +273,21 @@ constexpr int PlaceholderBitmask(const char* format) {
 //    absl::SubstituteAndAppend(boilerplate, format, args...);
 //  }
 //
-inline void SubstituteAndAppend(std::string* output, absl::string_view format) {
+inline void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                                absl::string_view format) {
   substitute_internal::SubstituteAndAppendArray(output, format, nullptr, 0);
 }
 
-inline void SubstituteAndAppend(std::string* output, absl::string_view format,
+inline void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                                absl::string_view format,
                                 const substitute_internal::Arg& a0) {
   const absl::string_view args[] = {a0.piece()};
   substitute_internal::SubstituteAndAppendArray(output, format, args,
                                                 ABSL_ARRAYSIZE(args));
 }
 
-inline void SubstituteAndAppend(std::string* output, absl::string_view format,
+inline void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                                absl::string_view format,
                                 const substitute_internal::Arg& a0,
                                 const substitute_internal::Arg& a1) {
   const absl::string_view args[] = {a0.piece(), a1.piece()};
@@ -290,7 +295,8 @@ inline void SubstituteAndAppend(std::string* output, absl::string_view format,
                                                 ABSL_ARRAYSIZE(args));
 }
 
-inline void SubstituteAndAppend(std::string* output, absl::string_view format,
+inline void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                                absl::string_view format,
                                 const substitute_internal::Arg& a0,
                                 const substitute_internal::Arg& a1,
                                 const substitute_internal::Arg& a2) {
@@ -299,7 +305,8 @@ inline void SubstituteAndAppend(std::string* output, absl::string_view format,
                                                 ABSL_ARRAYSIZE(args));
 }
 
-inline void SubstituteAndAppend(std::string* output, absl::string_view format,
+inline void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                                absl::string_view format,
                                 const substitute_internal::Arg& a0,
                                 const substitute_internal::Arg& a1,
                                 const substitute_internal::Arg& a2,
@@ -310,7 +317,8 @@ inline void SubstituteAndAppend(std::string* output, absl::string_view format,
                                                 ABSL_ARRAYSIZE(args));
 }
 
-inline void SubstituteAndAppend(std::string* output, absl::string_view format,
+inline void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                                absl::string_view format,
                                 const substitute_internal::Arg& a0,
                                 const substitute_internal::Arg& a1,
                                 const substitute_internal::Arg& a2,
@@ -322,27 +330,23 @@ inline void SubstituteAndAppend(std::string* output, absl::string_view format,
                                                 ABSL_ARRAYSIZE(args));
 }
 
-inline void SubstituteAndAppend(std::string* output, absl::string_view format,
-                                const substitute_internal::Arg& a0,
-                                const substitute_internal::Arg& a1,
-                                const substitute_internal::Arg& a2,
-                                const substitute_internal::Arg& a3,
-                                const substitute_internal::Arg& a4,
-                                const substitute_internal::Arg& a5) {
+inline void SubstituteAndAppend(
+    absl::Nonnull<std::string*> output, absl::string_view format,
+    const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
+    const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
+    const substitute_internal::Arg& a4, const substitute_internal::Arg& a5) {
   const absl::string_view args[] = {a0.piece(), a1.piece(), a2.piece(),
                                     a3.piece(), a4.piece(), a5.piece()};
   substitute_internal::SubstituteAndAppendArray(output, format, args,
                                                 ABSL_ARRAYSIZE(args));
 }
 
-inline void SubstituteAndAppend(std::string* output, absl::string_view format,
-                                const substitute_internal::Arg& a0,
-                                const substitute_internal::Arg& a1,
-                                const substitute_internal::Arg& a2,
-                                const substitute_internal::Arg& a3,
-                                const substitute_internal::Arg& a4,
-                                const substitute_internal::Arg& a5,
-                                const substitute_internal::Arg& a6) {
+inline void SubstituteAndAppend(
+    absl::Nonnull<std::string*> output, absl::string_view format,
+    const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
+    const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
+    const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
+    const substitute_internal::Arg& a6) {
   const absl::string_view args[] = {a0.piece(), a1.piece(), a2.piece(),
                                     a3.piece(), a4.piece(), a5.piece(),
                                     a6.piece()};
@@ -351,7 +355,7 @@ inline void SubstituteAndAppend(std::string* output, absl::string_view format,
 }
 
 inline void SubstituteAndAppend(
-    std::string* output, absl::string_view format,
+    absl::Nonnull<std::string*> output, absl::string_view format,
     const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
     const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
     const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
@@ -364,7 +368,7 @@ inline void SubstituteAndAppend(
 }
 
 inline void SubstituteAndAppend(
-    std::string* output, absl::string_view format,
+    absl::Nonnull<std::string*> output, absl::string_view format,
     const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
     const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
     const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
@@ -378,7 +382,7 @@ inline void SubstituteAndAppend(
 }
 
 inline void SubstituteAndAppend(
-    std::string* output, absl::string_view format,
+    absl::Nonnull<std::string*> output, absl::string_view format,
     const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
     const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
     const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
@@ -394,14 +398,16 @@ inline void SubstituteAndAppend(
 #if defined(ABSL_BAD_CALL_IF)
 // This body of functions catches cases where the number of placeholders
 // doesn't match the number of data arguments.
-void SubstituteAndAppend(std::string* output, const char* format)
+void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                         absl::Nonnull<const char*> format)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 0,
         "There were no substitution arguments "
         "but this format string either has a $[0-9] in it or contains "
         "an unescaped $ character (use $$ instead)");
 
-void SubstituteAndAppend(std::string* output, const char* format,
+void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                         absl::Nonnull<const char*> format,
                          const substitute_internal::Arg& a0)
     ABSL_BAD_CALL_IF(substitute_internal::PlaceholderBitmask(format) != 1,
                      "There was 1 substitution argument given, but "
@@ -409,7 +415,8 @@ void SubstituteAndAppend(std::string* output, const char* format,
                      "one of $1-$9, or contains an unescaped $ character (use "
                      "$$ instead)");
 
-void SubstituteAndAppend(std::string* output, const char* format,
+void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                         absl::Nonnull<const char*> format,
                          const substitute_internal::Arg& a0,
                          const substitute_internal::Arg& a1)
     ABSL_BAD_CALL_IF(
@@ -418,7 +425,8 @@ void SubstituteAndAppend(std::string* output, const char* format,
         "missing its $0/$1, contains one of $2-$9, or contains an "
         "unescaped $ character (use $$ instead)");
 
-void SubstituteAndAppend(std::string* output, const char* format,
+void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                         absl::Nonnull<const char*> format,
                          const substitute_internal::Arg& a0,
                          const substitute_internal::Arg& a1,
                          const substitute_internal::Arg& a2)
@@ -428,7 +436,8 @@ void SubstituteAndAppend(std::string* output, const char* format,
         "this format string is missing its $0/$1/$2, contains one of "
         "$3-$9, or contains an unescaped $ character (use $$ instead)");
 
-void SubstituteAndAppend(std::string* output, const char* format,
+void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                         absl::Nonnull<const char*> format,
                          const substitute_internal::Arg& a0,
                          const substitute_internal::Arg& a1,
                          const substitute_internal::Arg& a2,
@@ -439,7 +448,8 @@ void SubstituteAndAppend(std::string* output, const char* format,
         "this format string is missing its $0-$3, contains one of "
         "$4-$9, or contains an unescaped $ character (use $$ instead)");
 
-void SubstituteAndAppend(std::string* output, const char* format,
+void SubstituteAndAppend(absl::Nonnull<std::string*> output,
+                         absl::Nonnull<const char*> format,
                          const substitute_internal::Arg& a0,
                          const substitute_internal::Arg& a1,
                          const substitute_internal::Arg& a2,
@@ -451,13 +461,11 @@ void SubstituteAndAppend(std::string* output, const char* format,
         "this format string is missing its $0-$4, contains one of "
         "$5-$9, or contains an unescaped $ character (use $$ instead)");
 
-void SubstituteAndAppend(std::string* output, const char* format,
-                         const substitute_internal::Arg& a0,
-                         const substitute_internal::Arg& a1,
-                         const substitute_internal::Arg& a2,
-                         const substitute_internal::Arg& a3,
-                         const substitute_internal::Arg& a4,
-                         const substitute_internal::Arg& a5)
+void SubstituteAndAppend(
+    absl::Nonnull<std::string*> output, absl::Nonnull<const char*> format,
+    const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
+    const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
+    const substitute_internal::Arg& a4, const substitute_internal::Arg& a5)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 63,
         "There were 6 substitution arguments given, but "
@@ -465,10 +473,11 @@ void SubstituteAndAppend(std::string* output, const char* format,
         "$6-$9, or contains an unescaped $ character (use $$ instead)");
 
 void SubstituteAndAppend(
-    std::string* output, const char* format, const substitute_internal::Arg& a0,
-    const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
-    const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
-    const substitute_internal::Arg& a5, const substitute_internal::Arg& a6)
+    absl::Nonnull<std::string*> output, absl::Nonnull<const char*> format,
+    const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
+    const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
+    const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
+    const substitute_internal::Arg& a6)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 127,
         "There were 7 substitution arguments given, but "
@@ -476,11 +485,11 @@ void SubstituteAndAppend(
         "$7-$9, or contains an unescaped $ character (use $$ instead)");
 
 void SubstituteAndAppend(
-    std::string* output, const char* format, const substitute_internal::Arg& a0,
-    const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
-    const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
-    const substitute_internal::Arg& a5, const substitute_internal::Arg& a6,
-    const substitute_internal::Arg& a7)
+    absl::Nonnull<std::string*> output, absl::Nonnull<const char*> format,
+    const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
+    const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
+    const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
+    const substitute_internal::Arg& a6, const substitute_internal::Arg& a7)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 255,
         "There were 8 substitution arguments given, but "
@@ -488,11 +497,12 @@ void SubstituteAndAppend(
         "$8-$9, or contains an unescaped $ character (use $$ instead)");
 
 void SubstituteAndAppend(
-    std::string* output, const char* format, const substitute_internal::Arg& a0,
-    const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
-    const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
-    const substitute_internal::Arg& a5, const substitute_internal::Arg& a6,
-    const substitute_internal::Arg& a7, const substitute_internal::Arg& a8)
+    absl::Nonnull<std::string*> output, absl::Nonnull<const char*> format,
+    const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
+    const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
+    const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
+    const substitute_internal::Arg& a6, const substitute_internal::Arg& a7,
+    const substitute_internal::Arg& a8)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 511,
         "There were 9 substitution arguments given, but "
@@ -500,12 +510,12 @@ void SubstituteAndAppend(
         "contains an unescaped $ character (use $$ instead)");
 
 void SubstituteAndAppend(
-    std::string* output, const char* format, const substitute_internal::Arg& a0,
-    const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
-    const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
-    const substitute_internal::Arg& a5, const substitute_internal::Arg& a6,
-    const substitute_internal::Arg& a7, const substitute_internal::Arg& a8,
-    const substitute_internal::Arg& a9)
+    absl::Nonnull<std::string*> output, absl::Nonnull<const char*> format,
+    const substitute_internal::Arg& a0, const substitute_internal::Arg& a1,
+    const substitute_internal::Arg& a2, const substitute_internal::Arg& a3,
+    const substitute_internal::Arg& a4, const substitute_internal::Arg& a5,
+    const substitute_internal::Arg& a6, const substitute_internal::Arg& a7,
+    const substitute_internal::Arg& a8, const substitute_internal::Arg& a9)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 1023,
         "There were 10 substitution arguments given, but this "
@@ -633,20 +643,22 @@ ABSL_MUST_USE_RESULT inline std::string Substitute(
 #if defined(ABSL_BAD_CALL_IF)
 // This body of functions catches cases where the number of placeholders
 // doesn't match the number of data arguments.
-std::string Substitute(const char* format)
+std::string Substitute(absl::Nonnull<const char*> format)
     ABSL_BAD_CALL_IF(substitute_internal::PlaceholderBitmask(format) != 0,
                      "There were no substitution arguments "
                      "but this format string either has a $[0-9] in it or "
                      "contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0)
+std::string Substitute(absl::Nonnull<const char*> format,
+                       const substitute_internal::Arg& a0)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 1,
         "There was 1 substitution argument given, but "
         "this format string is missing its $0, contains one of $1-$9, "
         "or contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0,
+std::string Substitute(absl::Nonnull<const char*> format,
+                       const substitute_internal::Arg& a0,
                        const substitute_internal::Arg& a1)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 3,
@@ -654,7 +666,8 @@ std::string Substitute(const char* format, const substitute_internal::Arg& a0,
         "this format string is missing its $0/$1, contains one of "
         "$2-$9, or contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0,
+std::string Substitute(absl::Nonnull<const char*> format,
+                       const substitute_internal::Arg& a0,
                        const substitute_internal::Arg& a1,
                        const substitute_internal::Arg& a2)
     ABSL_BAD_CALL_IF(
@@ -663,7 +676,8 @@ std::string Substitute(const char* format, const substitute_internal::Arg& a0,
         "this format string is missing its $0/$1/$2, contains one of "
         "$3-$9, or contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0,
+std::string Substitute(absl::Nonnull<const char*> format,
+                       const substitute_internal::Arg& a0,
                        const substitute_internal::Arg& a1,
                        const substitute_internal::Arg& a2,
                        const substitute_internal::Arg& a3)
@@ -673,7 +687,8 @@ std::string Substitute(const char* format, const substitute_internal::Arg& a0,
         "this format string is missing its $0-$3, contains one of "
         "$4-$9, or contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0,
+std::string Substitute(absl::Nonnull<const char*> format,
+                       const substitute_internal::Arg& a0,
                        const substitute_internal::Arg& a1,
                        const substitute_internal::Arg& a2,
                        const substitute_internal::Arg& a3,
@@ -684,7 +699,8 @@ std::string Substitute(const char* format, const substitute_internal::Arg& a0,
         "this format string is missing its $0-$4, contains one of "
         "$5-$9, or contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0,
+std::string Substitute(absl::Nonnull<const char*> format,
+                       const substitute_internal::Arg& a0,
                        const substitute_internal::Arg& a1,
                        const substitute_internal::Arg& a2,
                        const substitute_internal::Arg& a3,
@@ -696,27 +712,23 @@ std::string Substitute(const char* format, const substitute_internal::Arg& a0,
         "this format string is missing its $0-$5, contains one of "
         "$6-$9, or contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0,
-                       const substitute_internal::Arg& a1,
-                       const substitute_internal::Arg& a2,
-                       const substitute_internal::Arg& a3,
-                       const substitute_internal::Arg& a4,
-                       const substitute_internal::Arg& a5,
-                       const substitute_internal::Arg& a6)
+std::string Substitute(
+    absl::Nonnull<const char*> format, const substitute_internal::Arg& a0,
+    const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
+    const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
+    const substitute_internal::Arg& a5, const substitute_internal::Arg& a6)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 127,
         "There were 7 substitution arguments given, but "
         "this format string is missing its $0-$6, contains one of "
         "$7-$9, or contains an unescaped $ character (use $$ instead)");
 
-std::string Substitute(const char* format, const substitute_internal::Arg& a0,
-                       const substitute_internal::Arg& a1,
-                       const substitute_internal::Arg& a2,
-                       const substitute_internal::Arg& a3,
-                       const substitute_internal::Arg& a4,
-                       const substitute_internal::Arg& a5,
-                       const substitute_internal::Arg& a6,
-                       const substitute_internal::Arg& a7)
+std::string Substitute(
+    absl::Nonnull<const char*> format, const substitute_internal::Arg& a0,
+    const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
+    const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
+    const substitute_internal::Arg& a5, const substitute_internal::Arg& a6,
+    const substitute_internal::Arg& a7)
     ABSL_BAD_CALL_IF(
         substitute_internal::PlaceholderBitmask(format) != 255,
         "There were 8 substitution arguments given, but "
@@ -724,7 +736,7 @@ std::string Substitute(const char* format, const substitute_internal::Arg& a0,
         "$8-$9, or contains an unescaped $ character (use $$ instead)");
 
 std::string Substitute(
-    const char* format, const substitute_internal::Arg& a0,
+    absl::Nonnull<const char*> format, const substitute_internal::Arg& a0,
     const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
     const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
     const substitute_internal::Arg& a5, const substitute_internal::Arg& a6,
@@ -736,7 +748,7 @@ std::string Substitute(
         "contains an unescaped $ character (use $$ instead)");
 
 std::string Substitute(
-    const char* format, const substitute_internal::Arg& a0,
+    absl::Nonnull<const char*> format, const substitute_internal::Arg& a0,
     const substitute_internal::Arg& a1, const substitute_internal::Arg& a2,
     const substitute_internal::Arg& a3, const substitute_internal::Arg& a4,
     const substitute_internal::Arg& a5, const substitute_internal::Arg& a6,
diff --git a/contrib/restricted/abseil-cpp/absl/strings/ya.make b/contrib/restricted/abseil-cpp/absl/strings/ya.make
index 99b03d7bd6..dffec44d18 100644
--- a/contrib/restricted/abseil-cpp/absl/strings/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/strings/ya.make
@@ -27,7 +27,7 @@ SRCS(
     crc/internal/crc.cc
     crc/internal/crc_cord_state.cc
     crc/internal/crc_memcpy_fallback.cc
-    crc/internal/crc_memcpy_x86_64.cc
+    crc/internal/crc_memcpy_x86_arm_combined.cc
     crc/internal/crc_non_temporal_memcpy.cc
     crc/internal/crc_x86_arm_combined.cc
     status/statusor.cc
@@ -45,7 +45,6 @@ SRCS(
     strings/internal/cord_rep_btree_reader.cc
     strings/internal/cord_rep_consume.cc
     strings/internal/cord_rep_crc.cc
-    strings/internal/cord_rep_ring.cc
     strings/internal/cordz_functions.cc
     strings/internal/cordz_handle.cc
     strings/internal/cordz_info.cc
diff --git a/contrib/restricted/abseil-cpp/absl/synchronization/internal/pthread_waiter.h b/contrib/restricted/abseil-cpp/absl/synchronization/internal/pthread_waiter.h
index 206aefa47c..23db76ad44 100644
--- a/contrib/restricted/abseil-cpp/absl/synchronization/internal/pthread_waiter.h
+++ b/contrib/restricted/abseil-cpp/absl/synchronization/internal/pthread_waiter.h
@@ -16,7 +16,7 @@
 #ifndef ABSL_SYNCHRONIZATION_INTERNAL_PTHREAD_WAITER_H_
 #define ABSL_SYNCHRONIZATION_INTERNAL_PTHREAD_WAITER_H_
 
-#ifndef _WIN32
+#if !defined(_WIN32) && !defined(__MINGW32__)
 #include <pthread.h>
 
 #include "absl/base/config.h"
@@ -55,6 +55,6 @@ class PthreadWaiter : public WaiterCrtp<PthreadWaiter> {
 ABSL_NAMESPACE_END
 }  // namespace absl
 
-#endif  // ndef _WIN32
+#endif  // !defined(_WIN32) && !defined(__MINGW32__)
 
 #endif  // ABSL_SYNCHRONIZATION_INTERNAL_PTHREAD_WAITER_H_
diff --git a/contrib/restricted/abseil-cpp/absl/synchronization/internal/win32_waiter.h b/contrib/restricted/abseil-cpp/absl/synchronization/internal/win32_waiter.h
index 87eb617cbd..fdab264e8c 100644
--- a/contrib/restricted/abseil-cpp/absl/synchronization/internal/win32_waiter.h
+++ b/contrib/restricted/abseil-cpp/absl/synchronization/internal/win32_waiter.h
@@ -20,7 +20,8 @@
 #include <sdkddkver.h>
 #endif
 
-#if defined(_WIN32) && _WIN32_WINNT >= _WIN32_WINNT_VISTA
+#if defined(_WIN32) && !defined(__MINGW32__) && \
+    _WIN32_WINNT >= _WIN32_WINNT_VISTA
 
 #include "absl/base/config.h"
 #include "absl/synchronization/internal/kernel_timeout.h"
@@ -65,6 +66,7 @@ class Win32Waiter : public WaiterCrtp<Win32Waiter> {
 ABSL_NAMESPACE_END
 }  // namespace absl
 
-#endif  // defined(_WIN32) && _WIN32_WINNT >= _WIN32_WINNT_VISTA
+#endif  // defined(_WIN32) && !defined(__MINGW32__) &&
+        // _WIN32_WINNT >= _WIN32_WINNT_VISTA
 
 #endif  // ABSL_SYNCHRONIZATION_INTERNAL_WIN32_WAITER_H_
diff --git a/contrib/restricted/abseil-cpp/absl/synchronization/mutex.cc b/contrib/restricted/abseil-cpp/absl/synchronization/mutex.cc
index 3aa5560a32..cb3c7e74ec 100644
--- a/contrib/restricted/abseil-cpp/absl/synchronization/mutex.cc
+++ b/contrib/restricted/abseil-cpp/absl/synchronization/mutex.cc
@@ -129,11 +129,15 @@ enum DelayMode { AGGRESSIVE, GENTLE };
 
 struct ABSL_CACHELINE_ALIGNED MutexGlobals {
   absl::once_flag once;
-  int spinloop_iterations = 0;
+  // Note: this variable is initialized separately in Mutex::LockSlow,
+  // so that Mutex::Lock does not have a stack frame in optimized build.
+  std::atomic<int> spinloop_iterations{0};
   int32_t mutex_sleep_spins[2] = {};
   absl::Duration mutex_sleep_time;
 };
 
+ABSL_CONST_INIT static MutexGlobals globals;
+
 absl::Duration MeasureTimeToYield() {
   absl::Time before = absl::Now();
   ABSL_INTERNAL_C_SYMBOL(AbslInternalMutexYield)();
@@ -141,33 +145,30 @@ absl::Duration MeasureTimeToYield() {
 }
 
 const MutexGlobals& GetMutexGlobals() {
-  ABSL_CONST_INIT static MutexGlobals data;
-  absl::base_internal::LowLevelCallOnce(&data.once, [&]() {
+  absl::base_internal::LowLevelCallOnce(&globals.once, [&]() {
     if (absl::base_internal::NumCPUs() > 1) {
-      // If this is multiprocessor, allow spinning. If the mode is
-      // aggressive then spin many times before yielding. If the mode is
-      // gentle then spin only a few times before yielding. Aggressive spinning
-      // is used to ensure that an Unlock() call, which must get the spin lock
-      // for any thread to make progress gets it without undue delay.
-      data.spinloop_iterations = 1500;
-      data.mutex_sleep_spins[AGGRESSIVE] = 5000;
-      data.mutex_sleep_spins[GENTLE] = 250;
-      data.mutex_sleep_time = absl::Microseconds(10);
+      // If the mode is aggressive then spin many times before yielding.
+      // If the mode is gentle then spin only a few times before yielding.
+      // Aggressive spinning is used to ensure that an Unlock() call,
+      // which must get the spin lock for any thread to make progress gets it
+      // without undue delay.
+      globals.mutex_sleep_spins[AGGRESSIVE] = 5000;
+      globals.mutex_sleep_spins[GENTLE] = 250;
+      globals.mutex_sleep_time = absl::Microseconds(10);
     } else {
       // If this a uniprocessor, only yield/sleep. Real-time threads are often
       // unable to yield, so the sleep time needs to be long enough to keep
       // the calling thread asleep until scheduling happens.
-      data.spinloop_iterations = 0;
-      data.mutex_sleep_spins[AGGRESSIVE] = 0;
-      data.mutex_sleep_spins[GENTLE] = 0;
-      data.mutex_sleep_time = MeasureTimeToYield() * 5;
-      data.mutex_sleep_time =
-          std::min(data.mutex_sleep_time, absl::Milliseconds(1));
-      data.mutex_sleep_time =
-          std::max(data.mutex_sleep_time, absl::Microseconds(10));
+      globals.mutex_sleep_spins[AGGRESSIVE] = 0;
+      globals.mutex_sleep_spins[GENTLE] = 0;
+      globals.mutex_sleep_time = MeasureTimeToYield() * 5;
+      globals.mutex_sleep_time =
+          std::min(globals.mutex_sleep_time, absl::Milliseconds(1));
+      globals.mutex_sleep_time =
+          std::max(globals.mutex_sleep_time, absl::Microseconds(10));
     }
   });
-  return data;
+  return globals;
 }
 }  // namespace
 
@@ -202,31 +203,23 @@ int MutexDelay(int32_t c, int mode) {
 // Ensure that "(*pv & bits) == bits" by doing an atomic update of "*pv" to
 // "*pv | bits" if necessary.  Wait until (*pv & wait_until_clear)==0
 // before making any change.
+// Returns true if bits were previously unset and set by the call.
 // This is used to set flags in mutex and condition variable words.
-static void AtomicSetBits(std::atomic<intptr_t>* pv, intptr_t bits,
+static bool AtomicSetBits(std::atomic<intptr_t>* pv, intptr_t bits,
                           intptr_t wait_until_clear) {
-  intptr_t v;
-  do {
-    v = pv->load(std::memory_order_relaxed);
-  } while ((v & bits) != bits &&
-           ((v & wait_until_clear) != 0 ||
-            !pv->compare_exchange_weak(v, v | bits, std::memory_order_release,
-                                       std::memory_order_relaxed)));
-}
-
-// Ensure that "(*pv & bits) == 0" by doing an atomic update of "*pv" to
-// "*pv & ~bits" if necessary.  Wait until (*pv & wait_until_clear)==0
-// before making any change.
-// This is used to unset flags in mutex and condition variable words.
-static void AtomicClearBits(std::atomic<intptr_t>* pv, intptr_t bits,
-                            intptr_t wait_until_clear) {
-  intptr_t v;
-  do {
-    v = pv->load(std::memory_order_relaxed);
-  } while ((v & bits) != 0 &&
-           ((v & wait_until_clear) != 0 ||
-            !pv->compare_exchange_weak(v, v & ~bits, std::memory_order_release,
-                                       std::memory_order_relaxed)));
+  for (;;) {
+    intptr_t v = pv->load(std::memory_order_relaxed);
+    if ((v & bits) == bits) {
+      return false;
+    }
+    if ((v & wait_until_clear) != 0) {
+      continue;
+    }
+    if (pv->compare_exchange_weak(v, v | bits, std::memory_order_release,
+                                  std::memory_order_relaxed)) {
+      return true;
+    }
+  }
 }
 
 //------------------------------------------------------------------
@@ -337,12 +330,49 @@ static SynchEvent* EnsureSynchEvent(std::atomic<intptr_t>* addr,
                                     const char* name, intptr_t bits,
                                     intptr_t lockbit) {
   uint32_t h = reinterpret_cast<uintptr_t>(addr) % kNSynchEvent;
-  SynchEvent* e;
-  // first look for existing SynchEvent struct..
   synch_event_mu.Lock();
-  for (e = synch_event[h];
-       e != nullptr && e->masked_addr != base_internal::HidePtr(addr);
-       e = e->next) {
+  // When a Mutex/CondVar is destroyed, we don't remove the associated
+  // SynchEvent to keep destructors empty in release builds for performance
+  // reasons. If the current call is the first to set bits (kMuEvent/kCVEvent),
+  // we don't look up the existing even because (if it exists, it must be for
+  // the previous Mutex/CondVar that existed at the same address).
+  // The leaking events must not be a problem for tests, which should create
+  // bounded amount of events. And debug logging is not supposed to be enabled
+  // in production. However, if it's accidentally enabled, or briefly enabled
+  // for some debugging, we don't want to crash the program. Instead we drop
+  // all events, if we accumulated too many of them. Size of a single event
+  // is ~48 bytes, so 100K events is ~5 MB.
+  // Additionally we could delete the old event for the same address,
+  // but it would require a better hashmap (if we accumulate too many events,
+  // linked lists will grow and traversing them will be very slow).
+  constexpr size_t kMaxSynchEventCount = 100 << 10;
+  // Total number of live synch events.
+  static size_t synch_event_count ABSL_GUARDED_BY(synch_event_mu);
+  if (++synch_event_count > kMaxSynchEventCount) {
+    synch_event_count = 0;
+    ABSL_RAW_LOG(ERROR,
+                 "Accumulated %zu Mutex debug objects. If you see this"
+                 " in production, it may mean that the production code"
+                 " accidentally calls "
+                 "Mutex/CondVar::EnableDebugLog/EnableInvariantDebugging.",
+                 kMaxSynchEventCount);
+    for (auto*& head : synch_event) {
+      for (auto* e = head; e != nullptr;) {
+        SynchEvent* next = e->next;
+        if (--(e->refcount) == 0) {
+          base_internal::LowLevelAlloc::Free(e);
+        }
+        e = next;
+      }
+      head = nullptr;
+    }
+  }
+  SynchEvent* e = nullptr;
+  if (!AtomicSetBits(addr, bits, lockbit)) {
+    for (e = synch_event[h];
+         e != nullptr && e->masked_addr != base_internal::HidePtr(addr);
+         e = e->next) {
+    }
   }
   if (e == nullptr) {  // no SynchEvent struct found; make one.
     if (name == nullptr) {
@@ -358,7 +388,6 @@ static SynchEvent* EnsureSynchEvent(std::atomic<intptr_t>* addr,
     e->log = false;
     strcpy(e->name, name);  // NOLINT(runtime/printf)
     e->next = synch_event[h];
-    AtomicSetBits(addr, bits, lockbit);
     synch_event[h] = e;
   } else {
     e->refcount++;  // for return value
@@ -367,11 +396,6 @@ static SynchEvent* EnsureSynchEvent(std::atomic<intptr_t>* addr,
   return e;
 }
 
-// Deallocate the SynchEvent *e, whose refcount has fallen to zero.
-static void DeleteSynchEvent(SynchEvent* e) {
-  base_internal::LowLevelAlloc::Free(e);
-}
-
 // Decrement the reference count of *e, or do nothing if e==null.
 static void UnrefSynchEvent(SynchEvent* e) {
   if (e != nullptr) {
@@ -379,36 +403,11 @@ static void UnrefSynchEvent(SynchEvent* e) {
     bool del = (--(e->refcount) == 0);
     synch_event_mu.Unlock();
     if (del) {
-      DeleteSynchEvent(e);
+      base_internal::LowLevelAlloc::Free(e);
     }
   }
 }
 
-// Forget the mapping from the object (Mutex or CondVar) at address addr
-// to SynchEvent object, and clear "bits" in its word (waiting until lockbit
-// is clear before doing so).
-static void ForgetSynchEvent(std::atomic<intptr_t>* addr, intptr_t bits,
-                             intptr_t lockbit) {
-  uint32_t h = reinterpret_cast<uintptr_t>(addr) % kNSynchEvent;
-  SynchEvent** pe;
-  SynchEvent* e;
-  synch_event_mu.Lock();
-  for (pe = &synch_event[h];
-       (e = *pe) != nullptr && e->masked_addr != base_internal::HidePtr(addr);
-       pe = &e->next) {
-  }
-  bool del = false;
-  if (e != nullptr) {
-    *pe = e->next;
-    del = (--(e->refcount) == 0);
-  }
-  AtomicClearBits(addr, bits, lockbit);
-  synch_event_mu.Unlock();
-  if (del) {
-    DeleteSynchEvent(e);
-  }
-}
-
 // Return a refcounted reference to the SynchEvent of the object at address
 // "addr", if any.  The pointer returned is valid until the UnrefSynchEvent() is
 // called.
@@ -579,31 +578,25 @@ static SynchLocksHeld* Synch_GetAllLocks() {
 
 // Post on "w"'s associated PerThreadSem.
 void Mutex::IncrementSynchSem(Mutex* mu, PerThreadSynch* w) {
-  if (mu) {
-    ABSL_TSAN_MUTEX_PRE_DIVERT(mu, 0);
-    // We miss synchronization around passing PerThreadSynch between threads
-    // since it happens inside of the Mutex code, so we need to ignore all
-    // accesses to the object.
-    ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN();
-    PerThreadSem::Post(w->thread_identity());
-    ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END();
-    ABSL_TSAN_MUTEX_POST_DIVERT(mu, 0);
-  } else {
-    PerThreadSem::Post(w->thread_identity());
-  }
+  static_cast<void>(mu);  // Prevent unused param warning in non-TSAN builds.
+  ABSL_TSAN_MUTEX_PRE_DIVERT(mu, 0);
+  // We miss synchronization around passing PerThreadSynch between threads
+  // since it happens inside of the Mutex code, so we need to ignore all
+  // accesses to the object.
+  ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN();
+  PerThreadSem::Post(w->thread_identity());
+  ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END();
+  ABSL_TSAN_MUTEX_POST_DIVERT(mu, 0);
 }
 
 // Wait on "w"'s associated PerThreadSem; returns false if timeout expired.
 bool Mutex::DecrementSynchSem(Mutex* mu, PerThreadSynch* w, KernelTimeout t) {
-  if (mu) {
-    ABSL_TSAN_MUTEX_PRE_DIVERT(mu, 0);
-  }
+  static_cast<void>(mu);  // Prevent unused param warning in non-TSAN builds.
+  ABSL_TSAN_MUTEX_PRE_DIVERT(mu, 0);
   assert(w == Synch_GetPerThread());
   static_cast<void>(w);
   bool res = PerThreadSem::Wait(t);
-  if (mu) {
-    ABSL_TSAN_MUTEX_POST_DIVERT(mu, 0);
-  }
+  ABSL_TSAN_MUTEX_POST_DIVERT(mu, 0);
   return res;
 }
 
@@ -682,6 +675,7 @@ static const intptr_t kMuOne = 0x0100;  // a count of one reader
 // flags passed to Enqueue and LockSlow{,WithTimeout,Loop}
 static const int kMuHasBlocked = 0x01;  // already blocked (MUST == 1)
 static const int kMuIsCond = 0x02;      // conditional waiter (CV or Condition)
+static const int kMuIsFer = 0x04;       // wait morphing from a CondVar
 
 static_assert(PerThreadSynch::kAlignment > kMuLow,
               "PerThreadSynch::kAlignment must be greater than kMuLow");
@@ -737,25 +731,43 @@ static unsigned TsanFlags(Mutex::MuHow how) {
 }
 #endif
 
-static bool DebugOnlyIsExiting() {
-  return false;
-}
+#if defined(__APPLE__) || defined(ABSL_BUILD_DLL)
+// When building a dll symbol export lists may reference the destructor
+// and want it to be an exported symbol rather than an inline function.
+// Some apple builds also do dynamic library build but don't say it explicitly.
+Mutex::~Mutex() { Dtor(); }
+#endif
 
-Mutex::~Mutex() {
-  intptr_t v = mu_.load(std::memory_order_relaxed);
-  if ((v & kMuEvent) != 0 && !DebugOnlyIsExiting()) {
-    ForgetSynchEvent(&this->mu_, kMuEvent, kMuSpin);
-  }
+#if !defined(NDEBUG) || defined(ABSL_HAVE_THREAD_SANITIZER)
+void Mutex::Dtor() {
   if (kDebugMode) {
     this->ForgetDeadlockInfo();
   }
   ABSL_TSAN_MUTEX_DESTROY(this, __tsan_mutex_not_static);
 }
+#endif
 
 void Mutex::EnableDebugLog(const char* name) {
+  // Need to disable writes here and in EnableInvariantDebugging to prevent
+  // false race reports on SynchEvent objects. TSan ignores synchronization
+  // on synch_event_mu in Lock/Unlock/etc methods due to mutex annotations,
+  // but it sees few accesses to SynchEvent in EvalConditionAnnotated.
+  // If we don't ignore accesses here, it can result in false races
+  // between EvalConditionAnnotated and SynchEvent reuse in EnsureSynchEvent.
+  ABSL_ANNOTATE_IGNORE_WRITES_BEGIN();
   SynchEvent* e = EnsureSynchEvent(&this->mu_, name, kMuEvent, kMuSpin);
   e->log = true;
   UnrefSynchEvent(e);
+  // This prevents "error: undefined symbol: absl::Mutex::~Mutex()"
+  // in a release build (NDEBUG defined) when a test does "#undef NDEBUG"
+  // to use assert macro. In such case, the test does not get the dtor
+  // definition because it's supposed to be outline when NDEBUG is not defined,
+  // and this source file does not define one either because NDEBUG is defined.
+  // Since it's not possible to take address of a destructor, we move the
+  // actual destructor code into the separate Dtor function and force the
+  // compiler to emit this function even if it's inline by taking its address.
+  ABSL_ATTRIBUTE_UNUSED volatile auto dtor = &Mutex::Dtor;
+  ABSL_ANNOTATE_IGNORE_WRITES_END();
 }
 
 void EnableMutexInvariantDebugging(bool enabled) {
@@ -763,6 +775,7 @@ void EnableMutexInvariantDebugging(bool enabled) {
 }
 
 void Mutex::EnableInvariantDebugging(void (*invariant)(void*), void* arg) {
+  ABSL_ANNOTATE_IGNORE_WRITES_BEGIN();
   if (synch_check_invariants.load(std::memory_order_acquire) &&
       invariant != nullptr) {
     SynchEvent* e = EnsureSynchEvent(&this->mu_, nullptr, kMuEvent, kMuSpin);
@@ -770,6 +783,7 @@ void Mutex::EnableInvariantDebugging(void (*invariant)(void*), void* arg) {
     e->arg = arg;
     UnrefSynchEvent(e);
   }
+  ABSL_ANNOTATE_IGNORE_WRITES_END();
 }
 
 void SetMutexDeadlockDetectionMode(OnDeadlockCycle mode) {
@@ -920,20 +934,23 @@ static PerThreadSynch* Enqueue(PerThreadSynch* head, SynchWaitParams* waitp,
   s->wake = false;     // not being woken
   s->cond_waiter = ((flags & kMuIsCond) != 0);
 #ifdef ABSL_HAVE_PTHREAD_GETSCHEDPARAM
-  int64_t now_cycles = CycleClock::Now();
-  if (s->next_priority_read_cycles < now_cycles) {
-    // Every so often, update our idea of the thread's priority.
-    // pthread_getschedparam() is 5% of the block/wakeup time;
-    // CycleClock::Now() is 0.5%.
-    int policy;
-    struct sched_param param;
-    const int err = pthread_getschedparam(pthread_self(), &policy, &param);
-    if (err != 0) {
-      ABSL_RAW_LOG(ERROR, "pthread_getschedparam failed: %d", err);
-    } else {
-      s->priority = param.sched_priority;
-      s->next_priority_read_cycles =
-          now_cycles + static_cast<int64_t>(CycleClock::Frequency());
+  if ((flags & kMuIsFer) == 0) {
+    assert(s == Synch_GetPerThread());
+    int64_t now_cycles = CycleClock::Now();
+    if (s->next_priority_read_cycles < now_cycles) {
+      // Every so often, update our idea of the thread's priority.
+      // pthread_getschedparam() is 5% of the block/wakeup time;
+      // CycleClock::Now() is 0.5%.
+      int policy;
+      struct sched_param param;
+      const int err = pthread_getschedparam(pthread_self(), &policy, &param);
+      if (err != 0) {
+        ABSL_RAW_LOG(ERROR, "pthread_getschedparam failed: %d", err);
+      } else {
+        s->priority = param.sched_priority;
+        s->next_priority_read_cycles =
+            now_cycles + static_cast<int64_t>(CycleClock::Frequency());
+      }
     }
   }
 #endif
@@ -962,8 +979,7 @@ static PerThreadSynch* Enqueue(PerThreadSynch* head, SynchWaitParams* waitp,
         } while (s->priority <= advance_to->priority);
         // termination guaranteed because s->priority > head->priority
         // and head is the end of a skip chain
-      } else if (waitp->how == kExclusive &&
-                 Condition::GuaranteedEqual(waitp->cond, nullptr)) {
+      } else if (waitp->how == kExclusive && waitp->cond == nullptr) {
         // An unlocker could be scanning the queue, but we know it will recheck
         // the queue front for writers that have no condition, which is what s
         // is, so an insert at front is safe.
@@ -994,6 +1010,24 @@ static PerThreadSynch* Enqueue(PerThreadSynch* head, SynchWaitParams* waitp,
       if (MuEquivalentWaiter(s, s->next)) {  // s->may_skip is known to be true
         s->skip = s->next;                   // s may skip to its successor
       }
+    } else if ((flags & kMuHasBlocked) &&
+               (s->priority >= head->next->priority) &&
+               (!head->maybe_unlocking ||
+                (waitp->how == kExclusive &&
+                 Condition::GuaranteedEqual(waitp->cond, nullptr)))) {
+      // This thread has already waited, then was woken, then failed to acquire
+      // the mutex and now tries to requeue. Try to requeue it at head,
+      // otherwise it can suffer bad latency (wait whole queue several times).
+      // However, we need to be conservative. First, we need to ensure that we
+      // respect priorities. Then, we need to be careful to not break wait
+      // queue invariants: we require either that unlocker is not scanning
+      // the queue or that the current thread is a writer with no condition
+      // (unlocker will recheck the queue for such waiters).
+      s->next = head->next;
+      head->next = s;
+      if (MuEquivalentWaiter(s, s->next)) {  // s->may_skip is known to be true
+        s->skip = s->next;                   // s may skip to its successor
+      }
     } else {  // enqueue not done any other way, so
               // we're inserting s at the back
       // s will become new head; copy data from head into it
@@ -1472,7 +1506,7 @@ void Mutex::AssertNotHeld() const {
 // Attempt to acquire *mu, and return whether successful.  The implementation
 // may spin for a short while if the lock cannot be acquired immediately.
 static bool TryAcquireWithSpinning(std::atomic<intptr_t>* mu) {
-  int c = GetMutexGlobals().spinloop_iterations;
+  int c = globals.spinloop_iterations.load(std::memory_order_relaxed);
   do {  // do/while somewhat faster on AMD
     intptr_t v = mu->load(std::memory_order_relaxed);
     if ((v & (kMuReader | kMuEvent)) != 0) {
@@ -1492,11 +1526,12 @@ void Mutex::Lock() {
   GraphId id = DebugOnlyDeadlockCheck(this);
   intptr_t v = mu_.load(std::memory_order_relaxed);
   // try fast acquire, then spin loop
-  if ((v & (kMuWriter | kMuReader | kMuEvent)) != 0 ||
-      !mu_.compare_exchange_strong(v, kMuWriter | v, std::memory_order_acquire,
-                                   std::memory_order_relaxed)) {
+  if (ABSL_PREDICT_FALSE((v & (kMuWriter | kMuReader | kMuEvent)) != 0) ||
+      ABSL_PREDICT_FALSE(!mu_.compare_exchange_strong(
+          v, kMuWriter | v, std::memory_order_acquire,
+          std::memory_order_relaxed))) {
     // try spin acquire, then slow loop
-    if (!TryAcquireWithSpinning(&this->mu_)) {
+    if (ABSL_PREDICT_FALSE(!TryAcquireWithSpinning(&this->mu_))) {
       this->LockSlow(kExclusive, nullptr, 0);
     }
   }
@@ -1508,159 +1543,95 @@ void Mutex::ReaderLock() {
   ABSL_TSAN_MUTEX_PRE_LOCK(this, __tsan_mutex_read_lock);
   GraphId id = DebugOnlyDeadlockCheck(this);
   intptr_t v = mu_.load(std::memory_order_relaxed);
-  // try fast acquire, then slow loop
-  if ((v & (kMuWriter | kMuWait | kMuEvent)) != 0 ||
-      !mu_.compare_exchange_strong(v, (kMuReader | v) + kMuOne,
-                                   std::memory_order_acquire,
-                                   std::memory_order_relaxed)) {
-    this->LockSlow(kShared, nullptr, 0);
+  for (;;) {
+    // If there are non-readers holding the lock, use the slow loop.
+    if (ABSL_PREDICT_FALSE(v & (kMuWriter | kMuWait | kMuEvent)) != 0) {
+      this->LockSlow(kShared, nullptr, 0);
+      break;
+    }
+    // We can avoid the loop and only use the CAS when the lock is free or
+    // only held by readers.
+    if (ABSL_PREDICT_TRUE(mu_.compare_exchange_weak(
+            v, (kMuReader | v) + kMuOne, std::memory_order_acquire,
+            std::memory_order_relaxed))) {
+      break;
+    }
   }
   DebugOnlyLockEnter(this, id);
   ABSL_TSAN_MUTEX_POST_LOCK(this, __tsan_mutex_read_lock, 0);
 }
 
-void Mutex::LockWhen(const Condition& cond) {
-  ABSL_TSAN_MUTEX_PRE_LOCK(this, 0);
-  GraphId id = DebugOnlyDeadlockCheck(this);
-  this->LockSlow(kExclusive, &cond, 0);
-  DebugOnlyLockEnter(this, id);
-  ABSL_TSAN_MUTEX_POST_LOCK(this, 0, 0);
-}
-
-bool Mutex::LockWhenWithTimeout(const Condition& cond, absl::Duration timeout) {
-  ABSL_TSAN_MUTEX_PRE_LOCK(this, 0);
-  GraphId id = DebugOnlyDeadlockCheck(this);
-  bool res = LockSlowWithDeadline(kExclusive, &cond, KernelTimeout(timeout), 0);
-  DebugOnlyLockEnter(this, id);
-  ABSL_TSAN_MUTEX_POST_LOCK(this, 0, 0);
-  return res;
-}
-
-bool Mutex::LockWhenWithDeadline(const Condition& cond, absl::Time deadline) {
-  ABSL_TSAN_MUTEX_PRE_LOCK(this, 0);
-  GraphId id = DebugOnlyDeadlockCheck(this);
-  bool res =
-      LockSlowWithDeadline(kExclusive, &cond, KernelTimeout(deadline), 0);
-  DebugOnlyLockEnter(this, id);
-  ABSL_TSAN_MUTEX_POST_LOCK(this, 0, 0);
-  return res;
-}
-
-void Mutex::ReaderLockWhen(const Condition& cond) {
-  ABSL_TSAN_MUTEX_PRE_LOCK(this, __tsan_mutex_read_lock);
-  GraphId id = DebugOnlyDeadlockCheck(this);
-  this->LockSlow(kShared, &cond, 0);
-  DebugOnlyLockEnter(this, id);
-  ABSL_TSAN_MUTEX_POST_LOCK(this, __tsan_mutex_read_lock, 0);
-}
-
-bool Mutex::ReaderLockWhenWithTimeout(const Condition& cond,
-                                      absl::Duration timeout) {
-  ABSL_TSAN_MUTEX_PRE_LOCK(this, __tsan_mutex_read_lock);
-  GraphId id = DebugOnlyDeadlockCheck(this);
-  bool res = LockSlowWithDeadline(kShared, &cond, KernelTimeout(timeout), 0);
-  DebugOnlyLockEnter(this, id);
-  ABSL_TSAN_MUTEX_POST_LOCK(this, __tsan_mutex_read_lock, 0);
-  return res;
-}
-
-bool Mutex::ReaderLockWhenWithDeadline(const Condition& cond,
-                                       absl::Time deadline) {
-  ABSL_TSAN_MUTEX_PRE_LOCK(this, __tsan_mutex_read_lock);
+bool Mutex::LockWhenCommon(const Condition& cond,
+                           synchronization_internal::KernelTimeout t,
+                           bool write) {
+  MuHow how = write ? kExclusive : kShared;
+  ABSL_TSAN_MUTEX_PRE_LOCK(this, TsanFlags(how));
   GraphId id = DebugOnlyDeadlockCheck(this);
-  bool res = LockSlowWithDeadline(kShared, &cond, KernelTimeout(deadline), 0);
+  bool res = LockSlowWithDeadline(how, &cond, t, 0);
   DebugOnlyLockEnter(this, id);
-  ABSL_TSAN_MUTEX_POST_LOCK(this, __tsan_mutex_read_lock, 0);
+  ABSL_TSAN_MUTEX_POST_LOCK(this, TsanFlags(how), 0);
   return res;
 }
 
-void Mutex::Await(const Condition& cond) {
-  if (cond.Eval()) {  // condition already true; nothing to do
-    if (kDebugMode) {
-      this->AssertReaderHeld();
-    }
-  } else {  // normal case
-    ABSL_RAW_CHECK(this->AwaitCommon(cond, KernelTimeout::Never()),
-                   "condition untrue on return from Await");
-  }
-}
-
-bool Mutex::AwaitWithTimeout(const Condition& cond, absl::Duration timeout) {
-  if (cond.Eval()) {  // condition already true; nothing to do
-    if (kDebugMode) {
-      this->AssertReaderHeld();
-    }
-    return true;
+bool Mutex::AwaitCommon(const Condition& cond, KernelTimeout t) {
+  if (kDebugMode) {
+    this->AssertReaderHeld();
   }
-
-  KernelTimeout t{timeout};
-  bool res = this->AwaitCommon(cond, t);
-  ABSL_RAW_CHECK(res || t.has_timeout(),
-                 "condition untrue on return from Await");
-  return res;
-}
-
-bool Mutex::AwaitWithDeadline(const Condition& cond, absl::Time deadline) {
   if (cond.Eval()) {  // condition already true; nothing to do
-    if (kDebugMode) {
-      this->AssertReaderHeld();
-    }
     return true;
   }
-
-  KernelTimeout t{deadline};
-  bool res = this->AwaitCommon(cond, t);
-  ABSL_RAW_CHECK(res || t.has_timeout(),
-                 "condition untrue on return from Await");
-  return res;
-}
-
-bool Mutex::AwaitCommon(const Condition& cond, KernelTimeout t) {
-  this->AssertReaderHeld();
   MuHow how =
       (mu_.load(std::memory_order_relaxed) & kMuWriter) ? kExclusive : kShared;
   ABSL_TSAN_MUTEX_PRE_UNLOCK(this, TsanFlags(how));
   SynchWaitParams waitp(how, &cond, t, nullptr /*no cvmu*/,
                         Synch_GetPerThreadAnnotated(this),
                         nullptr /*no cv_word*/);
-  int flags = kMuHasBlocked;
-  if (!Condition::GuaranteedEqual(&cond, nullptr)) {
-    flags |= kMuIsCond;
-  }
   this->UnlockSlow(&waitp);
   this->Block(waitp.thread);
   ABSL_TSAN_MUTEX_POST_UNLOCK(this, TsanFlags(how));
   ABSL_TSAN_MUTEX_PRE_LOCK(this, TsanFlags(how));
-  this->LockSlowLoop(&waitp, flags);
+  this->LockSlowLoop(&waitp, kMuHasBlocked | kMuIsCond);
   bool res = waitp.cond != nullptr ||  // => cond known true from LockSlowLoop
              EvalConditionAnnotated(&cond, this, true, false, how == kShared);
   ABSL_TSAN_MUTEX_POST_LOCK(this, TsanFlags(how), 0);
+  ABSL_RAW_CHECK(res || t.has_timeout(),
+                 "condition untrue on return from Await");
   return res;
 }
 
 bool Mutex::TryLock() {
   ABSL_TSAN_MUTEX_PRE_LOCK(this, __tsan_mutex_try_lock);
   intptr_t v = mu_.load(std::memory_order_relaxed);
-  if ((v & (kMuWriter | kMuReader | kMuEvent)) == 0 &&  // try fast acquire
-      mu_.compare_exchange_strong(v, kMuWriter | v, std::memory_order_acquire,
-                                  std::memory_order_relaxed)) {
-    DebugOnlyLockEnter(this);
-    ABSL_TSAN_MUTEX_POST_LOCK(this, __tsan_mutex_try_lock, 0);
-    return true;
-  }
-  if ((v & kMuEvent) != 0) {                      // we're recording events
-    if ((v & kExclusive->slow_need_zero) == 0 &&  // try fast acquire
-        mu_.compare_exchange_strong(
-            v, (kExclusive->fast_or | v) + kExclusive->fast_add,
-            std::memory_order_acquire, std::memory_order_relaxed)) {
+  // Try fast acquire.
+  if (ABSL_PREDICT_TRUE((v & (kMuWriter | kMuReader | kMuEvent)) == 0)) {
+    if (ABSL_PREDICT_TRUE(mu_.compare_exchange_strong(
+            v, kMuWriter | v, std::memory_order_acquire,
+            std::memory_order_relaxed))) {
       DebugOnlyLockEnter(this);
-      PostSynchEvent(this, SYNCH_EV_TRYLOCK_SUCCESS);
       ABSL_TSAN_MUTEX_POST_LOCK(this, __tsan_mutex_try_lock, 0);
       return true;
-    } else {
-      PostSynchEvent(this, SYNCH_EV_TRYLOCK_FAILED);
     }
+  } else if (ABSL_PREDICT_FALSE((v & kMuEvent) != 0)) {
+    // We're recording events.
+    return TryLockSlow();
+  }
+  ABSL_TSAN_MUTEX_POST_LOCK(
+      this, __tsan_mutex_try_lock | __tsan_mutex_try_lock_failed, 0);
+  return false;
+}
+
+ABSL_ATTRIBUTE_NOINLINE bool Mutex::TryLockSlow() {
+  intptr_t v = mu_.load(std::memory_order_relaxed);
+  if ((v & kExclusive->slow_need_zero) == 0 &&  // try fast acquire
+      mu_.compare_exchange_strong(
+          v, (kExclusive->fast_or | v) + kExclusive->fast_add,
+          std::memory_order_acquire, std::memory_order_relaxed)) {
+    DebugOnlyLockEnter(this);
+    PostSynchEvent(this, SYNCH_EV_TRYLOCK_SUCCESS);
+    ABSL_TSAN_MUTEX_POST_LOCK(this, __tsan_mutex_try_lock, 0);
+    return true;
   }
+  PostSynchEvent(this, SYNCH_EV_TRYLOCK_FAILED);
   ABSL_TSAN_MUTEX_POST_LOCK(
       this, __tsan_mutex_try_lock | __tsan_mutex_try_lock_failed, 0);
   return false;
@@ -1670,41 +1641,57 @@ bool Mutex::ReaderTryLock() {
   ABSL_TSAN_MUTEX_PRE_LOCK(this,
                            __tsan_mutex_read_lock | __tsan_mutex_try_lock);
   intptr_t v = mu_.load(std::memory_order_relaxed);
+  // Clang tends to unroll the loop when compiling with optimization.
+  // But in this case it just unnecessary increases code size.
+  // If CAS is failing due to contention, the jump cost is negligible.
+#if defined(__clang__)
+#pragma nounroll
+#endif
   // The while-loops (here and below) iterate only if the mutex word keeps
-  // changing (typically because the reader count changes) under the CAS.  We
-  // limit the number of attempts to avoid having to think about livelock.
-  int loop_limit = 5;
-  while ((v & (kMuWriter | kMuWait | kMuEvent)) == 0 && loop_limit != 0) {
-    if (mu_.compare_exchange_strong(v, (kMuReader | v) + kMuOne,
-                                    std::memory_order_acquire,
-                                    std::memory_order_relaxed)) {
+  // changing (typically because the reader count changes) under the CAS.
+  // We limit the number of attempts to avoid having to think about livelock.
+  for (int loop_limit = 5; loop_limit != 0; loop_limit--) {
+    if (ABSL_PREDICT_FALSE((v & (kMuWriter | kMuWait | kMuEvent)) != 0)) {
+      break;
+    }
+    if (ABSL_PREDICT_TRUE(mu_.compare_exchange_strong(
+            v, (kMuReader | v) + kMuOne, std::memory_order_acquire,
+            std::memory_order_relaxed))) {
       DebugOnlyLockEnter(this);
       ABSL_TSAN_MUTEX_POST_LOCK(
           this, __tsan_mutex_read_lock | __tsan_mutex_try_lock, 0);
       return true;
     }
-    loop_limit--;
-    v = mu_.load(std::memory_order_relaxed);
   }
-  if ((v & kMuEvent) != 0) {  // we're recording events
-    loop_limit = 5;
-    while ((v & kShared->slow_need_zero) == 0 && loop_limit != 0) {
-      if (mu_.compare_exchange_strong(v, (kMuReader | v) + kMuOne,
-                                      std::memory_order_acquire,
-                                      std::memory_order_relaxed)) {
-        DebugOnlyLockEnter(this);
-        PostSynchEvent(this, SYNCH_EV_READERTRYLOCK_SUCCESS);
-        ABSL_TSAN_MUTEX_POST_LOCK(
-            this, __tsan_mutex_read_lock | __tsan_mutex_try_lock, 0);
-        return true;
-      }
-      loop_limit--;
-      v = mu_.load(std::memory_order_relaxed);
-    }
-    if ((v & kMuEvent) != 0) {
-      PostSynchEvent(this, SYNCH_EV_READERTRYLOCK_FAILED);
+  if (ABSL_PREDICT_TRUE((v & kMuEvent) == 0)) {
+    ABSL_TSAN_MUTEX_POST_LOCK(this,
+                              __tsan_mutex_read_lock | __tsan_mutex_try_lock |
+                                  __tsan_mutex_try_lock_failed,
+                              0);
+    return false;
+  }
+  // we're recording events
+  return ReaderTryLockSlow();
+}
+
+ABSL_ATTRIBUTE_NOINLINE bool Mutex::ReaderTryLockSlow() {
+  intptr_t v = mu_.load(std::memory_order_relaxed);
+#if defined(__clang__)
+#pragma nounroll
+#endif
+  for (int loop_limit = 5; loop_limit != 0; loop_limit--) {
+    if ((v & kShared->slow_need_zero) == 0 &&
+        mu_.compare_exchange_strong(v, (kMuReader | v) + kMuOne,
+                                    std::memory_order_acquire,
+                                    std::memory_order_relaxed)) {
+      DebugOnlyLockEnter(this);
+      PostSynchEvent(this, SYNCH_EV_READERTRYLOCK_SUCCESS);
+      ABSL_TSAN_MUTEX_POST_LOCK(
+          this, __tsan_mutex_read_lock | __tsan_mutex_try_lock, 0);
+      return true;
     }
   }
+  PostSynchEvent(this, SYNCH_EV_READERTRYLOCK_FAILED);
   ABSL_TSAN_MUTEX_POST_LOCK(this,
                             __tsan_mutex_read_lock | __tsan_mutex_try_lock |
                                 __tsan_mutex_try_lock_failed,
@@ -1768,16 +1755,20 @@ void Mutex::ReaderUnlock() {
   DebugOnlyLockLeave(this);
   intptr_t v = mu_.load(std::memory_order_relaxed);
   assert((v & (kMuWriter | kMuReader)) == kMuReader);
-  if ((v & (kMuReader | kMuWait | kMuEvent)) == kMuReader) {
+  for (;;) {
+    if (ABSL_PREDICT_FALSE((v & (kMuReader | kMuWait | kMuEvent)) !=
+                           kMuReader)) {
+      this->UnlockSlow(nullptr /*no waitp*/);  // take slow path
+      break;
+    }
     // fast reader release (reader with no waiters)
     intptr_t clear = ExactlyOneReader(v) ? kMuReader | kMuOne : kMuOne;
-    if (mu_.compare_exchange_strong(v, v - clear, std::memory_order_release,
-                                    std::memory_order_relaxed)) {
-      ABSL_TSAN_MUTEX_POST_UNLOCK(this, __tsan_mutex_read_lock);
-      return;
+    if (ABSL_PREDICT_TRUE(
+            mu_.compare_exchange_strong(v, v - clear, std::memory_order_release,
+                                        std::memory_order_relaxed))) {
+      break;
     }
   }
-  this->UnlockSlow(nullptr /*no waitp*/);  // take slow path
   ABSL_TSAN_MUTEX_POST_UNLOCK(this, __tsan_mutex_read_lock);
 }
 
@@ -1812,6 +1803,22 @@ static intptr_t IgnoreWaitingWritersMask(int flag) {
 // Internal version of LockWhen().  See LockSlowWithDeadline()
 ABSL_ATTRIBUTE_NOINLINE void Mutex::LockSlow(MuHow how, const Condition* cond,
                                              int flags) {
+  // Note: we specifically initialize spinloop_iterations after the first use
+  // in TryAcquireWithSpinning so that Lock function does not have any non-tail
+  // calls and consequently a stack frame. It's fine to have spinloop_iterations
+  // uninitialized (meaning no spinning) in all initial uncontended Lock calls
+  // and in the first contended call. After that we will have
+  // spinloop_iterations properly initialized.
+  if (ABSL_PREDICT_FALSE(
+          globals.spinloop_iterations.load(std::memory_order_relaxed) == 0)) {
+    if (absl::base_internal::NumCPUs() > 1) {
+      // If this is multiprocessor, allow spinning.
+      globals.spinloop_iterations.store(1500, std::memory_order_relaxed);
+    } else {
+      // If this a uniprocessor, only yield/sleep.
+      globals.spinloop_iterations.store(-1, std::memory_order_relaxed);
+    }
+  }
   ABSL_RAW_CHECK(
       this->LockSlowWithDeadline(how, cond, KernelTimeout::Never(), flags),
       "condition untrue on return from LockSlow");
@@ -1913,7 +1920,7 @@ bool Mutex::LockSlowWithDeadline(MuHow how, const Condition* cond,
   SynchWaitParams waitp(how, cond, t, nullptr /*no cvmu*/,
                         Synch_GetPerThreadAnnotated(this),
                         nullptr /*no cv_word*/);
-  if (!Condition::GuaranteedEqual(cond, nullptr)) {
+  if (cond != nullptr) {
     flags |= kMuIsCond;
   }
   if (unlock) {
@@ -2103,7 +2110,6 @@ ABSL_ATTRIBUTE_NOINLINE void Mutex::UnlockSlow(SynchWaitParams* waitp) {
   // head of the list searched previously, or zero
   PerThreadSynch* old_h = nullptr;
   // a condition that's known to be false.
-  const Condition* known_false = nullptr;
   PerThreadSynch* wake_list = kPerThreadSynchNull;  // list of threads to wake
   intptr_t wr_wait = 0;  // set to kMuWrWait if we wake a reader and a
                          // later writer could have acquired the lock
@@ -2207,7 +2213,7 @@ ABSL_ATTRIBUTE_NOINLINE void Mutex::UnlockSlow(SynchWaitParams* waitp) {
         }
       }
       if (h->next->waitp->how == kExclusive &&
-          Condition::GuaranteedEqual(h->next->waitp->cond, nullptr)) {
+          h->next->waitp->cond == nullptr) {
         // easy case: writer with no condition; no need to search
         pw = h;  // wake w, the successor of h (=pw)
         w = h->next;
@@ -2290,10 +2296,8 @@ ABSL_ATTRIBUTE_NOINLINE void Mutex::UnlockSlow(SynchWaitParams* waitp) {
           w_walk->wake = false;
           if (w_walk->waitp->cond ==
                   nullptr ||  // no condition => vacuously true OR
-              (w_walk->waitp->cond != known_false &&
-               // this thread's condition is not known false, AND
-               //  is in fact true
-               EvalConditionIgnored(this, w_walk->waitp->cond))) {
+                              // this thread's condition is true
+              EvalConditionIgnored(this, w_walk->waitp->cond)) {
             if (w == nullptr) {
               w_walk->wake = true;  // can wake this waiter
               w = w_walk;
@@ -2307,8 +2311,6 @@ ABSL_ATTRIBUTE_NOINLINE void Mutex::UnlockSlow(SynchWaitParams* waitp) {
             } else {  // writer with true condition
               wr_wait = kMuWrWait;
             }
-          } else {                              // can't wake; condition false
-            known_false = w_walk->waitp->cond;  // remember last false condition
           }
           if (w_walk->wake) {  // we're waking reader w_walk
             pw_walk = w_walk;  // don't skip similar waiters
@@ -2414,10 +2416,10 @@ void Mutex::Fer(PerThreadSynch* w) {
   int c = 0;
   ABSL_RAW_CHECK(w->waitp->cond == nullptr,
                  "Mutex::Fer while waiting on Condition");
-  ABSL_RAW_CHECK(!w->waitp->timeout.has_timeout(),
-                 "Mutex::Fer while in timed wait");
   ABSL_RAW_CHECK(w->waitp->cv_word == nullptr,
                  "Mutex::Fer with pending CondVar queueing");
+  // The CondVar timeout is not relevant for the Mutex wait.
+  w->waitp->timeout = {};
   for (;;) {
     intptr_t v = mu_.load(std::memory_order_relaxed);
     // Note: must not queue if the mutex is unlocked (nobody will wake it).
@@ -2436,7 +2438,8 @@ void Mutex::Fer(PerThreadSynch* w) {
     } else {
       if ((v & (kMuSpin | kMuWait)) == 0) {  // no waiters
         // This thread tries to become the one and only waiter.
-        PerThreadSynch* new_h = Enqueue(nullptr, w->waitp, v, kMuIsCond);
+        PerThreadSynch* new_h =
+            Enqueue(nullptr, w->waitp, v, kMuIsCond | kMuIsFer);
         ABSL_RAW_CHECK(new_h != nullptr,
                        "Enqueue failed");  // we must queue ourselves
         if (mu_.compare_exchange_strong(
@@ -2447,7 +2450,7 @@ void Mutex::Fer(PerThreadSynch* w) {
       } else if ((v & kMuSpin) == 0 &&
                  mu_.compare_exchange_strong(v, v | kMuSpin | kMuWait)) {
         PerThreadSynch* h = GetPerThreadSynch(v);
-        PerThreadSynch* new_h = Enqueue(h, w->waitp, v, kMuIsCond);
+        PerThreadSynch* new_h = Enqueue(h, w->waitp, v, kMuIsCond | kMuIsFer);
         ABSL_RAW_CHECK(new_h != nullptr,
                        "Enqueue failed");  // we must queue ourselves
         do {
@@ -2503,12 +2506,6 @@ void CondVar::EnableDebugLog(const char* name) {
   UnrefSynchEvent(e);
 }
 
-CondVar::~CondVar() {
-  if ((cv_.load(std::memory_order_relaxed) & kCvEvent) != 0) {
-    ForgetSynchEvent(&this->cv_, kCvEvent, kCvSpin);
-  }
-}
-
 // Remove thread s from the list of waiters on this condition variable.
 void CondVar::Remove(PerThreadSynch* s) {
   SchedulingGuard::ScopedDisable disable_rescheduling;
@@ -2659,33 +2656,6 @@ bool CondVar::WaitCommon(Mutex* mutex, KernelTimeout t) {
   return rc;
 }
 
-bool CondVar::WaitWithTimeout(Mutex* mu, absl::Duration timeout) {
-  return WaitCommon(mu, KernelTimeout(timeout));
-}
-
-bool CondVar::WaitWithDeadline(Mutex* mu, absl::Time deadline) {
-  return WaitCommon(mu, KernelTimeout(deadline));
-}
-
-void CondVar::Wait(Mutex* mu) { WaitCommon(mu, KernelTimeout::Never()); }
-
-// Wake thread w
-// If it was a timed wait, w will be waiting on w->cv
-// Otherwise, if it was not a Mutex mutex, w will be waiting on w->sem
-// Otherwise, w is transferred to the Mutex mutex via Mutex::Fer().
-void CondVar::Wakeup(PerThreadSynch* w) {
-  if (w->waitp->timeout.has_timeout() || w->waitp->cvmu == nullptr) {
-    // The waiting thread only needs to observe "w->state == kAvailable" to be
-    // released, we must cache "cvmu" before clearing "next".
-    Mutex* mu = w->waitp->cvmu;
-    w->next = nullptr;
-    w->state.store(PerThreadSynch::kAvailable, std::memory_order_release);
-    Mutex::IncrementSynchSem(mu, w);
-  } else {
-    w->waitp->cvmu->Fer(w);
-  }
-}
-
 void CondVar::Signal() {
   SchedulingGuard::ScopedDisable disable_rescheduling;
   ABSL_TSAN_MUTEX_PRE_SIGNAL(nullptr, 0);
@@ -2710,7 +2680,7 @@ void CondVar::Signal() {
       cv_.store((v & kCvEvent) | reinterpret_cast<intptr_t>(h),
                 std::memory_order_release);
       if (w != nullptr) {
-        CondVar::Wakeup(w);  // wake waiter, if there was one
+        w->waitp->cvmu->Fer(w);  // wake waiter, if there was one
         cond_var_tracer("Signal wakeup", this);
       }
       if ((v & kCvEvent) != 0) {
@@ -2746,7 +2716,7 @@ void CondVar::SignalAll() {
         do {  // for every thread, wake it up
           w = n;
           n = n->next;
-          CondVar::Wakeup(w);
+          w->waitp->cvmu->Fer(w);
         } while (w != h);
         cond_var_tracer("SignalAll wakeup", this);
       }
@@ -2810,17 +2780,11 @@ Condition::Condition(const bool* cond)
   StoreCallback(dereference);
 }
 
-bool Condition::Eval() const {
-  // eval_ == null for kTrue
-  return (this->eval_ == nullptr) || (*this->eval_)(this);
-}
+bool Condition::Eval() const { return (*this->eval_)(this); }
 
 bool Condition::GuaranteedEqual(const Condition* a, const Condition* b) {
-  // kTrue logic.
-  if (a == nullptr || a->eval_ == nullptr) {
-    return b == nullptr || b->eval_ == nullptr;
-  } else if (b == nullptr || b->eval_ == nullptr) {
-    return false;
+  if (a == nullptr || b == nullptr) {
+    return a == b;
   }
   // Check equality of the representative fields.
   return a->eval_ == b->eval_ && a->arg_ == b->arg_ &&
diff --git a/contrib/restricted/abseil-cpp/absl/synchronization/mutex.h b/contrib/restricted/abseil-cpp/absl/synchronization/mutex.h
index 645c26d9c3..d53a22bbd9 100644
--- a/contrib/restricted/abseil-cpp/absl/synchronization/mutex.h
+++ b/contrib/restricted/abseil-cpp/absl/synchronization/mutex.h
@@ -64,6 +64,7 @@
 #include <iterator>
 #include <string>
 
+#include "absl/base/attributes.h"
 #include "absl/base/const_init.h"
 #include "absl/base/internal/identity.h"
 #include "absl/base/internal/low_level_alloc.h"
@@ -324,7 +325,9 @@ class ABSL_LOCKABLE Mutex {
   // `true`, `Await()` *may* skip the release/re-acquire step.
   //
   // `Await()` requires that this thread holds this `Mutex` in some mode.
-  void Await(const Condition& cond);
+  void Await(const Condition& cond) {
+    AwaitCommon(cond, synchronization_internal::KernelTimeout::Never());
+  }
 
   // Mutex::LockWhen()
   // Mutex::ReaderLockWhen()
@@ -334,9 +337,15 @@ class ABSL_LOCKABLE Mutex {
   // be acquired, then atomically acquires this `Mutex`. `LockWhen()` is
   // logically equivalent to `*Lock(); Await();` though they may have different
   // performance characteristics.
-  void LockWhen(const Condition& cond) ABSL_EXCLUSIVE_LOCK_FUNCTION();
+  void LockWhen(const Condition& cond) ABSL_EXCLUSIVE_LOCK_FUNCTION() {
+    LockWhenCommon(cond, synchronization_internal::KernelTimeout::Never(),
+                   true);
+  }
 
-  void ReaderLockWhen(const Condition& cond) ABSL_SHARED_LOCK_FUNCTION();
+  void ReaderLockWhen(const Condition& cond) ABSL_SHARED_LOCK_FUNCTION() {
+    LockWhenCommon(cond, synchronization_internal::KernelTimeout::Never(),
+                   false);
+  }
 
   void WriterLockWhen(const Condition& cond) ABSL_EXCLUSIVE_LOCK_FUNCTION() {
     this->LockWhen(cond);
@@ -363,9 +372,13 @@ class ABSL_LOCKABLE Mutex {
   // Negative timeouts are equivalent to a zero timeout.
   //
   // This method requires that this thread holds this `Mutex` in some mode.
-  bool AwaitWithTimeout(const Condition& cond, absl::Duration timeout);
+  bool AwaitWithTimeout(const Condition& cond, absl::Duration timeout) {
+    return AwaitCommon(cond, synchronization_internal::KernelTimeout{timeout});
+  }
 
-  bool AwaitWithDeadline(const Condition& cond, absl::Time deadline);
+  bool AwaitWithDeadline(const Condition& cond, absl::Time deadline) {
+    return AwaitCommon(cond, synchronization_internal::KernelTimeout{deadline});
+  }
 
   // Mutex::LockWhenWithTimeout()
   // Mutex::ReaderLockWhenWithTimeout()
@@ -379,9 +392,15 @@ class ABSL_LOCKABLE Mutex {
   //
   // Negative timeouts are equivalent to a zero timeout.
   bool LockWhenWithTimeout(const Condition& cond, absl::Duration timeout)
-      ABSL_EXCLUSIVE_LOCK_FUNCTION();
+      ABSL_EXCLUSIVE_LOCK_FUNCTION() {
+    return LockWhenCommon(
+        cond, synchronization_internal::KernelTimeout{timeout}, true);
+  }
   bool ReaderLockWhenWithTimeout(const Condition& cond, absl::Duration timeout)
-      ABSL_SHARED_LOCK_FUNCTION();
+      ABSL_SHARED_LOCK_FUNCTION() {
+    return LockWhenCommon(
+        cond, synchronization_internal::KernelTimeout{timeout}, false);
+  }
   bool WriterLockWhenWithTimeout(const Condition& cond, absl::Duration timeout)
       ABSL_EXCLUSIVE_LOCK_FUNCTION() {
     return this->LockWhenWithTimeout(cond, timeout);
@@ -399,9 +418,15 @@ class ABSL_LOCKABLE Mutex {
   //
   // Deadlines in the past are equivalent to an immediate deadline.
   bool LockWhenWithDeadline(const Condition& cond, absl::Time deadline)
-      ABSL_EXCLUSIVE_LOCK_FUNCTION();
+      ABSL_EXCLUSIVE_LOCK_FUNCTION() {
+    return LockWhenCommon(
+        cond, synchronization_internal::KernelTimeout{deadline}, true);
+  }
   bool ReaderLockWhenWithDeadline(const Condition& cond, absl::Time deadline)
-      ABSL_SHARED_LOCK_FUNCTION();
+      ABSL_SHARED_LOCK_FUNCTION() {
+    return LockWhenCommon(
+        cond, synchronization_internal::KernelTimeout{deadline}, false);
+  }
   bool WriterLockWhenWithDeadline(const Condition& cond, absl::Time deadline)
       ABSL_EXCLUSIVE_LOCK_FUNCTION() {
     return this->LockWhenWithDeadline(cond, deadline);
@@ -497,15 +522,22 @@ class ABSL_LOCKABLE Mutex {
                 int flags) ABSL_ATTRIBUTE_COLD;
   // slow path release
   void UnlockSlow(SynchWaitParams* waitp) ABSL_ATTRIBUTE_COLD;
+  // TryLock slow path.
+  bool TryLockSlow();
+  // ReaderTryLock slow path.
+  bool ReaderTryLockSlow();
   // Common code between Await() and AwaitWithTimeout/Deadline()
   bool AwaitCommon(const Condition& cond,
                    synchronization_internal::KernelTimeout t);
+  bool LockWhenCommon(const Condition& cond,
+                      synchronization_internal::KernelTimeout t, bool write);
   // Attempt to remove thread s from queue.
   void TryRemove(base_internal::PerThreadSynch* s);
   // Block a thread on mutex.
   void Block(base_internal::PerThreadSynch* s);
   // Wake a thread; return successor.
   base_internal::PerThreadSynch* Wakeup(base_internal::PerThreadSynch* w);
+  void Dtor();
 
   friend class CondVar;   // for access to Trans()/Fer().
   void Trans(MuHow how);  // used for CondVar->Mutex transfer
@@ -708,23 +740,25 @@ class Condition {
   // a function template is passed as `func`. Also, the dummy `typename = void`
   // template parameter exists just to work around a MSVC mangling bug.
   template <typename T, typename = void>
-  Condition(bool (*func)(T*), typename absl::internal::identity<T>::type* arg);
+  Condition(bool (*func)(T*),
+            typename absl::internal::type_identity<T>::type* arg);
 
   // Templated version for invoking a method that returns a `bool`.
   //
   // `Condition(object, &Class::Method)` constructs a `Condition` that evaluates
   // `object->Method()`.
   //
-  // Implementation Note: `absl::internal::identity` is used to allow methods to
-  // come from base classes. A simpler signature like
+  // Implementation Note: `absl::internal::type_identity` is used to allow
+  // methods to come from base classes. A simpler signature like
   // `Condition(T*, bool (T::*)())` does not suffice.
   template <typename T>
-  Condition(T* object, bool (absl::internal::identity<T>::type::*method)());
+  Condition(T* object,
+            bool (absl::internal::type_identity<T>::type::*method)());
 
   // Same as above, for const members
   template <typename T>
   Condition(const T* object,
-            bool (absl::internal::identity<T>::type::*method)() const);
+            bool (absl::internal::type_identity<T>::type::*method)() const);
 
   // A Condition that returns the value of `*cond`
   explicit Condition(const bool* cond);
@@ -816,7 +850,7 @@ class Condition {
   static bool CallVoidPtrFunction(const Condition*);
   template <typename T>
   static bool CastAndCallFunction(const Condition* c);
-  template <typename T>
+  template <typename T, typename ConditionMethodPtr>
   static bool CastAndCallMethod(const Condition* c);
 
   // Helper methods for storing, validating, and reading callback arguments.
@@ -833,8 +867,10 @@ class Condition {
     std::memcpy(callback, callback_, sizeof(*callback));
   }
 
+  static bool AlwaysTrue(const Condition*) { return true; }
+
   // Used only to create kTrue.
-  constexpr Condition() = default;
+  constexpr Condition() : eval_(AlwaysTrue), arg_(nullptr) {}
 };
 
 // -----------------------------------------------------------------------------
@@ -877,7 +913,6 @@ class CondVar {
   // A `CondVar` allocated on the heap or on the stack can use the this
   // constructor.
   CondVar();
-  ~CondVar();
 
   // CondVar::Wait()
   //
@@ -886,7 +921,9 @@ class CondVar {
   // spurious wakeup), then reacquires the `Mutex` and returns.
   //
   // Requires and ensures that the current thread holds the `Mutex`.
-  void Wait(Mutex* mu);
+  void Wait(Mutex* mu) {
+    WaitCommon(mu, synchronization_internal::KernelTimeout::Never());
+  }
 
   // CondVar::WaitWithTimeout()
   //
@@ -901,7 +938,9 @@ class CondVar {
   // to return `true` or `false`.
   //
   // Requires and ensures that the current thread holds the `Mutex`.
-  bool WaitWithTimeout(Mutex* mu, absl::Duration timeout);
+  bool WaitWithTimeout(Mutex* mu, absl::Duration timeout) {
+    return WaitCommon(mu, synchronization_internal::KernelTimeout(timeout));
+  }
 
   // CondVar::WaitWithDeadline()
   //
@@ -918,7 +957,9 @@ class CondVar {
   // to return `true` or `false`.
   //
   // Requires and ensures that the current thread holds the `Mutex`.
-  bool WaitWithDeadline(Mutex* mu, absl::Time deadline);
+  bool WaitWithDeadline(Mutex* mu, absl::Time deadline) {
+    return WaitCommon(mu, synchronization_internal::KernelTimeout(deadline));
+  }
 
   // CondVar::Signal()
   //
@@ -940,7 +981,6 @@ class CondVar {
  private:
   bool WaitCommon(Mutex* mutex, synchronization_internal::KernelTimeout t);
   void Remove(base_internal::PerThreadSynch* s);
-  void Wakeup(base_internal::PerThreadSynch* w);
   std::atomic<intptr_t> cv_;  // Condition variable state.
   CondVar(const CondVar&) = delete;
   CondVar& operator=(const CondVar&) = delete;
@@ -1024,15 +1064,30 @@ inline Mutex::Mutex() : mu_(0) {
 
 inline constexpr Mutex::Mutex(absl::ConstInitType) : mu_(0) {}
 
+#if !defined(__APPLE__) && !defined(ABSL_BUILD_DLL)
+ABSL_ATTRIBUTE_ALWAYS_INLINE
+inline Mutex::~Mutex() { Dtor(); }
+#endif
+
+#if defined(NDEBUG) && !defined(ABSL_HAVE_THREAD_SANITIZER)
+// Use default (empty) destructor in release build for performance reasons.
+// We need to mark both Dtor and ~Mutex as always inline for inconsistent
+// builds that use both NDEBUG and !NDEBUG with dynamic libraries. In these
+// cases we want the empty functions to dissolve entirely rather than being
+// exported from dynamic libraries and potentially override the non-empty ones.
+ABSL_ATTRIBUTE_ALWAYS_INLINE
+inline void Mutex::Dtor() {}
+#endif
+
 inline CondVar::CondVar() : cv_(0) {}
 
 // static
-template <typename T>
+template <typename T, typename ConditionMethodPtr>
 bool Condition::CastAndCallMethod(const Condition* c) {
   T* object = static_cast<T*>(c->arg_);
-  bool (T::*method_pointer)();
-  c->ReadCallback(&method_pointer);
-  return (object->*method_pointer)();
+  ConditionMethodPtr condition_method_pointer;
+  c->ReadCallback(&condition_method_pointer);
+  return (object->*condition_method_pointer)();
 }
 
 // static
@@ -1054,25 +1109,25 @@ inline Condition::Condition(bool (*func)(T*), T* arg)
 }
 
 template <typename T, typename>
-inline Condition::Condition(bool (*func)(T*),
-                            typename absl::internal::identity<T>::type* arg)
+inline Condition::Condition(
+    bool (*func)(T*), typename absl::internal::type_identity<T>::type* arg)
     // Just delegate to the overload above.
     : Condition(func, arg) {}
 
 template <typename T>
-inline Condition::Condition(T* object,
-                            bool (absl::internal::identity<T>::type::*method)())
-    : eval_(&CastAndCallMethod<T>), arg_(object) {
+inline Condition::Condition(
+    T* object, bool (absl::internal::type_identity<T>::type::*method)())
+    : eval_(&CastAndCallMethod<T, decltype(method)>), arg_(object) {
   static_assert(sizeof(&method) <= sizeof(callback_),
                 "An overlarge method pointer was passed to Condition.");
   StoreCallback(method);
 }
 
 template <typename T>
-inline Condition::Condition(const T* object,
-                            bool (absl::internal::identity<T>::type::*method)()
-                                const)
-    : eval_(&CastAndCallMethod<T>),
+inline Condition::Condition(
+    const T* object,
+    bool (absl::internal::type_identity<T>::type::*method)() const)
+    : eval_(&CastAndCallMethod<const T, decltype(method)>),
       arg_(reinterpret_cast<void*>(const_cast<T*>(object))) {
   StoreCallback(method);
 }
diff --git a/contrib/restricted/abseil-cpp/absl/time/civil_time.h b/contrib/restricted/abseil-cpp/absl/time/civil_time.h
index 5855bc73a1..3e904a113d 100644
--- a/contrib/restricted/abseil-cpp/absl/time/civil_time.h
+++ b/contrib/restricted/abseil-cpp/absl/time/civil_time.h
@@ -462,6 +462,32 @@ std::string FormatCivilTime(CivilDay c);
 std::string FormatCivilTime(CivilMonth c);
 std::string FormatCivilTime(CivilYear c);
 
+// Support for StrFormat(), StrCat(), etc
+template <typename Sink>
+void AbslStringify(Sink& sink, CivilSecond c) {
+  sink.Append(FormatCivilTime(c));
+}
+template <typename Sink>
+void AbslStringify(Sink& sink, CivilMinute c) {
+  sink.Append(FormatCivilTime(c));
+}
+template <typename Sink>
+void AbslStringify(Sink& sink, CivilHour c) {
+  sink.Append(FormatCivilTime(c));
+}
+template <typename Sink>
+void AbslStringify(Sink& sink, CivilDay c) {
+  sink.Append(FormatCivilTime(c));
+}
+template <typename Sink>
+void AbslStringify(Sink& sink, CivilMonth c) {
+  sink.Append(FormatCivilTime(c));
+}
+template <typename Sink>
+void AbslStringify(Sink& sink, CivilYear c) {
+  sink.Append(FormatCivilTime(c));
+}
+
 // absl::ParseCivilTime()
 //
 // Parses a civil-time value from the specified `absl::string_view` into the
diff --git a/contrib/restricted/abseil-cpp/absl/time/clock.h b/contrib/restricted/abseil-cpp/absl/time/clock.h
index 5fe244d638..41d2cf2770 100644
--- a/contrib/restricted/abseil-cpp/absl/time/clock.h
+++ b/contrib/restricted/abseil-cpp/absl/time/clock.h
@@ -22,6 +22,9 @@
 #ifndef ABSL_TIME_CLOCK_H_
 #define ABSL_TIME_CLOCK_H_
 
+#include <cstdint>
+
+#include "absl/base/config.h"
 #include "absl/base/macros.h"
 #include "absl/time/time.h"
 
@@ -64,7 +67,8 @@ ABSL_NAMESPACE_END
 // By changing our extension points to be extern "C", we dodge this
 // check.
 extern "C" {
-void ABSL_INTERNAL_C_SYMBOL(AbslInternalSleepFor)(absl::Duration duration);
+ABSL_DLL void ABSL_INTERNAL_C_SYMBOL(AbslInternalSleepFor)(
+    absl::Duration duration);
 }  // extern "C"
 
 inline void absl::SleepFor(absl::Duration duration) {
diff --git a/contrib/restricted/abseil-cpp/absl/time/duration.cc b/contrib/restricted/abseil-cpp/absl/time/duration.cc
index 634e5d5845..bdb16e2109 100644
--- a/contrib/restricted/abseil-cpp/absl/time/duration.cc
+++ b/contrib/restricted/abseil-cpp/absl/time/duration.cc
@@ -55,8 +55,7 @@
 
 #include <algorithm>
 #include <cassert>
-#include <cctype>
-#include <cerrno>
+#include <chrono>  // NOLINT(build/c++11)
 #include <cmath>
 #include <cstdint>
 #include <cstdlib>
@@ -66,8 +65,9 @@
 #include <limits>
 #include <string>
 
+#include "absl/base/attributes.h"
 #include "absl/base/casts.h"
-#include "absl/base/macros.h"
+#include "absl/base/config.h"
 #include "absl/numeric/int128.h"
 #include "absl/strings/string_view.h"
 #include "absl/strings/strip.h"
diff --git a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/include/cctz/civil_time_detail.h b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/include/cctz/civil_time_detail.h
index a5b084e6be..2b0aed56c3 100644
--- a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/include/cctz/civil_time_detail.h
+++ b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/include/cctz/civil_time_detail.h
@@ -401,11 +401,11 @@ class civil_time {
       : civil_time(ct.f_) {}
 
   // Factories for the maximum/minimum representable civil_time.
-  static CONSTEXPR_F civil_time(max)() {
+  static CONSTEXPR_F auto(max)() -> civil_time {
     const auto max_year = (std::numeric_limits<std::int_least64_t>::max)();
     return civil_time(max_year, 12, 31, 23, 59, 59);
   }
-  static CONSTEXPR_F civil_time(min)() {
+  static CONSTEXPR_F auto(min)() -> civil_time {
     const auto min_year = (std::numeric_limits<std::int_least64_t>::min)();
     return civil_time(min_year, 1, 1, 0, 0, 0);
   }
diff --git a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_format.cc b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_format.cc
index 9b91f61cf0..e7e30a2fb7 100644
--- a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_format.cc
+++ b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_format.cc
@@ -19,7 +19,7 @@
 #endif
 
 #if defined(HAS_STRPTIME) && HAS_STRPTIME
-#if !defined(_XOPEN_SOURCE) && !defined(__OpenBSD__)
+#if !defined(_XOPEN_SOURCE) && !defined(__FreeBSD__) && !defined(__OpenBSD__)
 #define _XOPEN_SOURCE 500  // Exposes definitions for SUSv2 (UNIX 98).
 #endif
 #endif
diff --git a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_info.cc b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_info.cc
index f46198ffaa..b7178a6b67 100644
--- a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_info.cc
+++ b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/time_zone_info.cc
@@ -474,7 +474,8 @@ std::unique_ptr<ZoneInfoSource> AndroidZoneInfoSource::Open(
   const std::size_t pos = (name.compare(0, 5, "file:") == 0) ? 5 : 0;
 
   // See Android's libc/tzcode/bionic.cpp for additional information.
-  for (const char* tzdata : {"/data/misc/zoneinfo/current/tzdata",
+  for (const char* tzdata : {"/apex/com.android.tzdata/etc/tz/tzdata",
+                             "/data/misc/zoneinfo/current/tzdata",
                              "/system/usr/share/zoneinfo/tzdata"}) {
     auto fp = FOpen(tzdata, "rb");
     if (fp == nullptr) continue;
@@ -539,9 +540,16 @@ std::unique_ptr<ZoneInfoSource> FuchsiaZoneInfoSource::Open(
   // Prefixes where a Fuchsia component might find zoneinfo files,
   // in descending order of preference.
   const auto kTzdataPrefixes = {
+      // The tzdata from `config-data`.
       "/config/data/tzdata/",
+      // The tzdata bundled in the component's package.
       "/pkg/data/tzdata/",
+      // General data storage.
       "/data/tzdata/",
+      // The recommended path for routed-in tzdata files.
+      // See for details:
+      // https://fuchsia.dev/fuchsia-src/concepts/process/namespaces?hl=en#typical_directory_structure
+      "/config/tzdata/",
   };
   const auto kEmptyPrefix = {""};
   const bool name_absolute = (pos != name.size() && name[pos] == '/');
@@ -744,19 +752,6 @@ bool TimeZoneInfo::Load(ZoneInfoSource* zip) {
     version_ = zip->Version();
   }
 
-  // Trim redundant transitions. zic may have added these to work around
-  // differences between the glibc and reference implementations (see
-  // zic.c:dontmerge) or to avoid bugs in old readers. For us, they just
-  // get in the way when we do future_spec_ extension.
-  while (hdr.timecnt > 1) {
-    if (!EquivTransitions(transitions_[hdr.timecnt - 1].type_index,
-                          transitions_[hdr.timecnt - 2].type_index)) {
-      break;
-    }
-    hdr.timecnt -= 1;
-  }
-  transitions_.resize(hdr.timecnt);
-
   // Ensure that there is always a transition in the first half of the
   // time line (the second half is handled below) so that the signed
   // difference between a civil_second and the civil_second of its
diff --git a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/tzfile.h b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/tzfile.h
index 9613055db7..114026d066 100644
--- a/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/tzfile.h
+++ b/contrib/restricted/abseil-cpp/absl/time/internal/cctz/src/tzfile.h
@@ -21,14 +21,6 @@
 ** Information about time zone files.
 */
 
-#ifndef TZDIR
-#define TZDIR "/usr/share/zoneinfo" /* Time zone object file directory */
-#endif                              /* !defined TZDIR */
-
-#ifndef TZDEFAULT
-#define TZDEFAULT "/etc/localtime"
-#endif /* !defined TZDEFAULT */
-
 #ifndef TZDEFRULES
 #define TZDEFRULES "posixrules"
 #endif /* !defined TZDEFRULES */
diff --git a/contrib/restricted/abseil-cpp/absl/types/bad_any_cast.cc b/contrib/restricted/abseil-cpp/absl/types/bad_any_cast.cc
index b0592cc9bc..22558b48c2 100644
--- a/contrib/restricted/abseil-cpp/absl/types/bad_any_cast.cc
+++ b/contrib/restricted/abseil-cpp/absl/types/bad_any_cast.cc
@@ -43,4 +43,22 @@ void ThrowBadAnyCast() {
 ABSL_NAMESPACE_END
 }  // namespace absl
 
+#else
+
+// https://github.com/abseil/abseil-cpp/issues/1465
+// CMake builds on Apple platforms error when libraries are empty.
+// Our CMake configuration can avoid this error on header-only libraries,
+// but since this library is conditionally empty, including a single
+// variable is an easy workaround.
+#ifdef __APPLE__
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace types_internal {
+extern const char kAvoidEmptyBadAnyCastLibraryWarning;
+const char kAvoidEmptyBadAnyCastLibraryWarning = 0;
+}  // namespace types_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
+#endif  // __APPLE__
+
 #endif  // ABSL_USES_STD_ANY
diff --git a/contrib/restricted/abseil-cpp/absl/types/bad_optional_access.cc b/contrib/restricted/abseil-cpp/absl/types/bad_optional_access.cc
index 26aca70d9c..2552cc853a 100644
--- a/contrib/restricted/abseil-cpp/absl/types/bad_optional_access.cc
+++ b/contrib/restricted/abseil-cpp/absl/types/bad_optional_access.cc
@@ -45,4 +45,22 @@ void throw_bad_optional_access() {
 ABSL_NAMESPACE_END
 }  // namespace absl
 
+#else
+
+// https://github.com/abseil/abseil-cpp/issues/1465
+// CMake builds on Apple platforms error when libraries are empty.
+// Our CMake configuration can avoid this error on header-only libraries,
+// but since this library is conditionally empty, including a single
+// variable is an easy workaround.
+#ifdef __APPLE__
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace types_internal {
+extern const char kAvoidEmptyBadOptionalAccessLibraryWarning;
+const char kAvoidEmptyBadOptionalAccessLibraryWarning = 0;
+}  // namespace types_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
+#endif  // __APPLE__
+
 #endif  // ABSL_USES_STD_OPTIONAL
diff --git a/contrib/restricted/abseil-cpp/absl/types/bad_variant_access.cc b/contrib/restricted/abseil-cpp/absl/types/bad_variant_access.cc
index 3dc88cc09f..a76aa80dfa 100644
--- a/contrib/restricted/abseil-cpp/absl/types/bad_variant_access.cc
+++ b/contrib/restricted/abseil-cpp/absl/types/bad_variant_access.cc
@@ -61,4 +61,22 @@ void Rethrow() {
 ABSL_NAMESPACE_END
 }  // namespace absl
 
+#else
+
+// https://github.com/abseil/abseil-cpp/issues/1465
+// CMake builds on Apple platforms error when libraries are empty.
+// Our CMake configuration can avoid this error on header-only libraries,
+// but since this library is conditionally empty, including a single
+// variable is an easy workaround.
+#ifdef __APPLE__
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace types_internal {
+extern const char kAvoidEmptyBadVariantAccessLibraryWarning;
+const char kAvoidEmptyBadVariantAccessLibraryWarning = 0;
+}  // namespace types_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
+#endif  // __APPLE__
+
 #endif  // ABSL_USES_STD_VARIANT
diff --git a/contrib/restricted/abseil-cpp/absl/types/internal/variant.h b/contrib/restricted/abseil-cpp/absl/types/internal/variant.h
index fc8829e5d8..263d7b0947 100644
--- a/contrib/restricted/abseil-cpp/absl/types/internal/variant.h
+++ b/contrib/restricted/abseil-cpp/absl/types/internal/variant.h
@@ -1047,11 +1047,11 @@ class VariantStateBase {
   std::size_t index_;
 };
 
-using absl::internal::identity;
+using absl::internal::type_identity;
 
 // OverloadSet::Overload() is a unary function which is overloaded to
 // take any of the element types of the variant, by reference-to-const.
-// The return type of the overload on T is identity<T>, so that you
+// The return type of the overload on T is type_identity<T>, so that you
 // can statically determine which overload was called.
 //
 // Overload() is not defined, so it can only be called in unevaluated
@@ -1062,7 +1062,7 @@ struct OverloadSet;
 template <typename T, typename... Ts>
 struct OverloadSet<T, Ts...> : OverloadSet<Ts...> {
   using Base = OverloadSet<Ts...>;
-  static identity<T> Overload(const T&);
+  static type_identity<T> Overload(const T&);
   using Base::Overload;
 };
 
diff --git a/contrib/restricted/abseil-cpp/absl/types/optional.h b/contrib/restricted/abseil-cpp/absl/types/optional.h
index 0a8080dc1a..395fe62f29 100644
--- a/contrib/restricted/abseil-cpp/absl/types/optional.h
+++ b/contrib/restricted/abseil-cpp/absl/types/optional.h
@@ -61,6 +61,7 @@ ABSL_NAMESPACE_END
 #include <utility>
 
 #include "absl/base/attributes.h"
+#include "absl/base/nullability.h"
 #include "absl/base/internal/inline_variable.h"
 #include "absl/meta/type_traits.h"
 #include "absl/types/bad_optional_access.h"
@@ -415,11 +416,11 @@ class optional : private optional_internal::optional_data<T>,
   // `optional` is empty, behavior is undefined.
   //
   // If you need myOpt->foo in constexpr, use (*myOpt).foo instead.
-  const T* operator->() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
+  absl::Nonnull<const T*> operator->() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
     ABSL_HARDENING_ASSERT(this->engaged_);
     return std::addressof(this->data_);
   }
-  T* operator->() ABSL_ATTRIBUTE_LIFETIME_BOUND {
+  absl::Nonnull<T*> operator->() ABSL_ATTRIBUTE_LIFETIME_BOUND {
     ABSL_HARDENING_ASSERT(this->engaged_);
     return std::addressof(this->data_);
   }
diff --git a/contrib/restricted/abseil-cpp/absl/types/span.h b/contrib/restricted/abseil-cpp/absl/types/span.h
index 70ed8eb6fa..88cd759540 100644
--- a/contrib/restricted/abseil-cpp/absl/types/span.h
+++ b/contrib/restricted/abseil-cpp/absl/types/span.h
@@ -63,6 +63,7 @@
 #include "absl/base/attributes.h"
 #include "absl/base/internal/throw_delegate.h"
 #include "absl/base/macros.h"
+#include "absl/base/nullability.h"
 #include "absl/base/optimization.h"
 #include "absl/base/port.h"    // TODO(strel): remove this include
 #include "absl/meta/type_traits.h"
@@ -172,6 +173,8 @@ class Span {
  public:
   using element_type = T;
   using value_type = absl::remove_cv_t<T>;
+  // TODO(b/316099902) - pointer should be Nullable<T*>, but this makes it hard
+  // to recognize foreach loops as safe.
   using pointer = T*;
   using const_pointer = const T*;
   using reference = T&;
@@ -679,12 +682,12 @@ bool operator>=(Span<T> a, const U& b) {
 //   }
 //
 template <int&... ExplicitArgumentBarrier, typename T>
-constexpr Span<T> MakeSpan(T* ptr, size_t size) noexcept {
+constexpr Span<T> MakeSpan(absl::Nullable<T*> ptr, size_t size) noexcept {
   return Span<T>(ptr, size);
 }
 
 template <int&... ExplicitArgumentBarrier, typename T>
-Span<T> MakeSpan(T* begin, T* end) noexcept {
+Span<T> MakeSpan(absl::Nullable<T*> begin, absl::Nullable<T*> end) noexcept {
   return ABSL_HARDENING_ASSERT(begin <= end),
          Span<T>(begin, static_cast<size_t>(end - begin));
 }
@@ -725,12 +728,14 @@ constexpr Span<T> MakeSpan(T (&array)[N]) noexcept {
 //   ProcessInts(absl::MakeConstSpan(std::vector<int>{ 0, 0, 0 }));
 //
 template <int&... ExplicitArgumentBarrier, typename T>
-constexpr Span<const T> MakeConstSpan(T* ptr, size_t size) noexcept {
+constexpr Span<const T> MakeConstSpan(absl::Nullable<T*> ptr,
+                                      size_t size) noexcept {
   return Span<const T>(ptr, size);
 }
 
 template <int&... ExplicitArgumentBarrier, typename T>
-Span<const T> MakeConstSpan(T* begin, T* end) noexcept {
+Span<const T> MakeConstSpan(absl::Nullable<T*> begin,
+                            absl::Nullable<T*> end) noexcept {
   return ABSL_HARDENING_ASSERT(begin <= end), Span<const T>(begin, end - begin);
 }
 
diff --git a/contrib/restricted/abseil-cpp/absl/utility/utility.h b/contrib/restricted/abseil-cpp/absl/utility/utility.h
index bf9232209a..fc0d1f6551 100644
--- a/contrib/restricted/abseil-cpp/absl/utility/utility.h
+++ b/contrib/restricted/abseil-cpp/absl/utility/utility.h
@@ -12,17 +12,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //
-// This header file contains C++11 versions of standard <utility> header
-// abstractions available within C++14 and C++17, and are designed to be drop-in
+// This header file contains C++14 versions of standard <utility> header
+// abstractions available within C++17, and are designed to be drop-in
 // replacement for code compliant with C++14 and C++17.
 //
 // The following abstractions are defined:
 //
-//   * integer_sequence<T, Ints...>  == std::integer_sequence<T, Ints...>
-//   * index_sequence<Ints...>       == std::index_sequence<Ints...>
-//   * make_integer_sequence<T, N>   == std::make_integer_sequence<T, N>
-//   * make_index_sequence<N>        == std::make_index_sequence<N>
-//   * index_sequence_for<Ts...>     == std::index_sequence_for<Ts...>
 //   * apply<Functor, Tuple>         == std::apply<Functor, Tuple>
 //   * exchange<T>                   == std::exchange<T>
 //   * make_from_tuple<T>            == std::make_from_tuple<T>
@@ -33,7 +28,6 @@
 //
 // References:
 //
-//  https://en.cppreference.com/w/cpp/utility/integer_sequence
 //  https://en.cppreference.com/w/cpp/utility/apply
 //  http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3658.html
 
@@ -53,68 +47,18 @@
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
-// integer_sequence
-//
-// Class template representing a compile-time integer sequence. An instantiation
-// of `integer_sequence<T, Ints...>` has a sequence of integers encoded in its
-// type through its template arguments (which is a common need when
-// working with C++11 variadic templates). `absl::integer_sequence` is designed
-// to be a drop-in replacement for C++14's `std::integer_sequence`.
-//
-// Example:
-//
-//   template< class T, T... Ints >
-//   void user_function(integer_sequence<T, Ints...>);
-//
-//   int main()
-//   {
-//     // user_function's `T` will be deduced to `int` and `Ints...`
-//     // will be deduced to `0, 1, 2, 3, 4`.
-//     user_function(make_integer_sequence<int, 5>());
-//   }
-template <typename T, T... Ints>
-struct integer_sequence {
-  using value_type = T;
-  static constexpr size_t size() noexcept { return sizeof...(Ints); }
-};
-
-// index_sequence
-//
-// A helper template for an `integer_sequence` of `size_t`,
-// `absl::index_sequence` is designed to be a drop-in replacement for C++14's
-// `std::index_sequence`.
-template <size_t... Ints>
-using index_sequence = integer_sequence<size_t, Ints...>;
+// Historical note: Abseil once provided implementations of these
+// abstractions for platforms that had not yet provided them. Those
+// platforms are no longer supported. New code should simply use the
+// the ones from std directly.
+using std::index_sequence;
+using std::index_sequence_for;
+using std::integer_sequence;
+using std::make_index_sequence;
+using std::make_integer_sequence;
 
 namespace utility_internal {
 
-template <typename Seq, size_t SeqSize, size_t Rem>
-struct Extend;
-
-// Note that SeqSize == sizeof...(Ints). It's passed explicitly for efficiency.
-template <typename T, T... Ints, size_t SeqSize>
-struct Extend<integer_sequence<T, Ints...>, SeqSize, 0> {
-  using type = integer_sequence<T, Ints..., (Ints + SeqSize)...>;
-};
-
-template <typename T, T... Ints, size_t SeqSize>
-struct Extend<integer_sequence<T, Ints...>, SeqSize, 1> {
-  using type = integer_sequence<T, Ints..., (Ints + SeqSize)..., 2 * SeqSize>;
-};
-
-// Recursion helper for 'make_integer_sequence<T, N>'.
-// 'Gen<T, N>::type' is an alias for 'integer_sequence<T, 0, 1, ... N-1>'.
-template <typename T, size_t N>
-struct Gen {
-  using type =
-      typename Extend<typename Gen<T, N / 2>::type, N / 2, N % 2>::type;
-};
-
-template <typename T>
-struct Gen<T, 0> {
-  using type = integer_sequence<T>;
-};
-
 template <typename T>
 struct InPlaceTypeTag {
   explicit InPlaceTypeTag() = delete;
@@ -131,32 +75,6 @@ struct InPlaceIndexTag {
 
 }  // namespace utility_internal
 
-// Compile-time sequences of integers
-
-// make_integer_sequence
-//
-// This template alias is equivalent to
-// `integer_sequence<int, 0, 1, ..., N-1>`, and is designed to be a drop-in
-// replacement for C++14's `std::make_integer_sequence`.
-template <typename T, T N>
-using make_integer_sequence = typename utility_internal::Gen<T, N>::type;
-
-// make_index_sequence
-//
-// This template alias is equivalent to `index_sequence<0, 1, ..., N-1>`,
-// and is designed to be a drop-in replacement for C++14's
-// `std::make_index_sequence`.
-template <size_t N>
-using make_index_sequence = make_integer_sequence<size_t, N>;
-
-// index_sequence_for
-//
-// Converts a typename pack into an index sequence of the same length, and
-// is designed to be a drop-in replacement for C++14's
-// `std::index_sequence_for()`
-template <typename... Ts>
-using index_sequence_for = make_index_sequence<sizeof...(Ts)>;
-
 // Tag types
 
 #ifdef ABSL_USES_STD_OPTIONAL
diff --git a/contrib/restricted/abseil-cpp/absl/utility/ya.make b/contrib/restricted/abseil-cpp/absl/utility/ya.make
index 3b66e3e400..3f9af85fe6 100644
--- a/contrib/restricted/abseil-cpp/absl/utility/ya.make
+++ b/contrib/restricted/abseil-cpp/absl/utility/ya.make
@@ -6,9 +6,9 @@ LICENSE(Apache-2.0)
 
 LICENSE_TEXTS(.yandex_meta/licenses.list.txt)
 
-VERSION(20230802.1)
+VERSION(20240116.0)
 
-ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20230802.1.tar.gz)
+ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20240116.0.tar.gz)
 
 NO_RUNTIME()
 
diff --git a/contrib/restricted/abseil-cpp/ya.make b/contrib/restricted/abseil-cpp/ya.make
index c89fe4570a..36452ac10e 100644
--- a/contrib/restricted/abseil-cpp/ya.make
+++ b/contrib/restricted/abseil-cpp/ya.make
@@ -6,9 +6,9 @@ LICENSE(Apache-2.0)
 
 LICENSE_TEXTS(.yandex_meta/licenses.list.txt)
 
-VERSION(20230802.1)
+VERSION(20240116.0)
 
-ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20230802.1.tar.gz)
+ORIGINAL_SOURCE(https://github.com/abseil/abseil-cpp/archive/20240116.0.tar.gz)
 
 PEERDIR(
     contrib/restricted/abseil-cpp/absl/algorithm