Update libc++ to revision ab0554b2 (31 Jan 2022).

Notable changes:
* allow using thread safety annotation in MinGW mode
* implement compare_{strong,weak,partial}_fallback
* omit atomic_{,un}signed_lock_free on platforms that doesn't support lock free atomics
* set enable_borrowed_range template variable for ref_view and empty_view
* fix bug in reverse_iterator::operator=
* move some function from directory_iterator.cpp to a header so that they can be reused
* fix bug in ranges::advance when try to advance by 0
* fix missing constraint which affects common_iterator for output iterators
* correctly handle move-only iterators in move_iterator
* make base() method in counted_iterator and transform_view::iterator noexcept
* remove C++03 workarounds in reference_wrapper, since clang supports necessary features in C++03 mode
* simplify convertible_to concept implementation
* fix issue with __convertible_to_non_slicing rejecting correct case
* remove excessive wrapping in std::ref and std::cref
* fix std::seed_seq constructors
* remove std::basic_string base class when using ABI v2
* std::basic_string::reserve now never shrinks in all C++ modes

ref:b62ec6bac0283b075dd2348bad7e8a271155b378

3 files changed, 83 insertions, 90 deletions

diff --git a/contrib/libs/cxxsupp/libcxx/src/filesystem/directory_iterator.cpp b/contrib/libs/cxxsupp/libcxx/src/filesystem/directory_iterator.cpp
index de7ded45140..fa793f68295 100644
--- a/contrib/libs/cxxsupp/libcxx/src/filesystem/directory_iterator.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/filesystem/directory_iterator.cpp
@@ -9,97 +9,12 @@
 #include "__config"
 #include "filesystem"
 #include "stack"
-#if defined(_LIBCPP_WIN32API)
-#define WIN32_LEAN_AND_MEAN
-#define NOMINMAX
-#include <windows.h>
-#else
-#include <dirent.h>
-#endif
 #include <errno.h>
 
 #include "filesystem_common.h"
 
 _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
 
-namespace detail {
-namespace {
-
-#if !defined(_LIBCPP_WIN32API)
-
-#if defined(DT_BLK)
-template <class DirEntT, class = decltype(DirEntT::d_type)>
-static file_type get_file_type(DirEntT* ent, int) {
-  switch (ent->d_type) {
-  case DT_BLK:
-    return file_type::block;
-  case DT_CHR:
-    return file_type::character;
-  case DT_DIR:
-    return file_type::directory;
-  case DT_FIFO:
-    return file_type::fifo;
-  case DT_LNK:
-    return file_type::symlink;
-  case DT_REG:
-    return file_type::regular;
-  case DT_SOCK:
-    return file_type::socket;
-  // Unlike in lstat, hitting "unknown" here simply means that the underlying
-  // filesystem doesn't support d_type. Report is as 'none' so we correctly
-  // set the cache to empty.
-  case DT_UNKNOWN:
-    break;
-  }
-  return file_type::none;
-}
-#endif // defined(DT_BLK)
-
-template <class DirEntT>
-static file_type get_file_type(DirEntT*, long) {
-  return file_type::none;
-}
-
-static pair<string_view, file_type> posix_readdir(DIR* dir_stream,
-                                                  error_code& ec) {
-  struct dirent* dir_entry_ptr = nullptr;
-  errno = 0; // zero errno in order to detect errors
-  ec.clear();
-  if ((dir_entry_ptr = ::readdir(dir_stream)) == nullptr) {
-    if (errno)
-      ec = capture_errno();
-    return {};
-  } else {
-    return {dir_entry_ptr->d_name, get_file_type(dir_entry_ptr, 0)};
-  }
-}
-#else
-// defined(_LIBCPP_WIN32API)
-
-static file_type get_file_type(const WIN32_FIND_DATAW& data) {
-  if (data.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT &&
-      data.dwReserved0 == IO_REPARSE_TAG_SYMLINK)
-    return file_type::symlink;
-  if (data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
-    return file_type::directory;
-  return file_type::regular;
-}
-static uintmax_t get_file_size(const WIN32_FIND_DATAW& data) {
-  return (static_cast<uint64_t>(data.nFileSizeHigh) << 32) + data.nFileSizeLow;
-}
-static file_time_type get_write_time(const WIN32_FIND_DATAW& data) {
-  ULARGE_INTEGER tmp;
-  const FILETIME& time = data.ftLastWriteTime;
-  tmp.u.LowPart = time.dwLowDateTime;
-  tmp.u.HighPart = time.dwHighDateTime;
-  return file_time_type(file_time_type::duration(tmp.QuadPart));
-}
-
-#endif
-
-} // namespace
-} // namespace detail
-
 using detail::ErrorHandler;
 
 #if defined(_LIBCPP_WIN32API)
@@ -197,9 +112,9 @@ public:
       : __stream_(nullptr), __root_(root) {
     if ((__stream_ = ::opendir(root.c_str())) == nullptr) {
       ec = detail::capture_errno();
-      const bool allow_eacess =
+      const bool allow_eacces =
           bool(opts & directory_options::skip_permission_denied);
-      if (allow_eacess && ec.value() == EACCES)
+      if (allow_eacces && ec.value() == EACCES)
         ec.clear();
       return;
     }
diff --git a/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h b/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h
index a3642df4486..b693476518f 100644
--- a/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h
+++ b/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h
@@ -20,12 +20,19 @@
 #include "ratio"
 #include "system_error"
 
+#if defined(_LIBCPP_WIN32API)
+# define WIN32_LEAN_AND_MEAN
+# define NOMINMAX
+# include <windows.h>
+#endif
+
 #if !defined(_LIBCPP_WIN32API)
-# include <unistd.h>
+# include <dirent.h>   // for DIR & friends
+# include <fcntl.h>    /* values for fchmodat */
 # include <sys/stat.h>
 # include <sys/statvfs.h>
 # include <sys/time.h> // for ::utimes as used in __last_write_time
-# include <fcntl.h>    /* values for fchmodat */
+# include <unistd.h>
 #endif
 
 #include "../include/apple_availability.h"
@@ -537,7 +544,76 @@ bool set_file_times(const path& p, std::array<TimeSpec, 2> const& TS,
   return posix_utimensat(p, TS, ec);
 #endif
 }
-#endif /* !_LIBCPP_WIN32API */
+
+#if defined(DT_BLK)
+template <class DirEntT, class = decltype(DirEntT::d_type)>
+static file_type get_file_type(DirEntT* ent, int) {
+  switch (ent->d_type) {
+  case DT_BLK:
+    return file_type::block;
+  case DT_CHR:
+    return file_type::character;
+  case DT_DIR:
+    return file_type::directory;
+  case DT_FIFO:
+    return file_type::fifo;
+  case DT_LNK:
+    return file_type::symlink;
+  case DT_REG:
+    return file_type::regular;
+  case DT_SOCK:
+    return file_type::socket;
+  // Unlike in lstat, hitting "unknown" here simply means that the underlying
+  // filesystem doesn't support d_type. Report is as 'none' so we correctly
+  // set the cache to empty.
+  case DT_UNKNOWN:
+    break;
+  }
+  return file_type::none;
+}
+#endif // defined(DT_BLK)
+
+template <class DirEntT>
+static file_type get_file_type(DirEntT*, long) {
+  return file_type::none;
+}
+
+static pair<string_view, file_type> posix_readdir(DIR* dir_stream,
+                                                  error_code& ec) {
+  struct dirent* dir_entry_ptr = nullptr;
+  errno = 0; // zero errno in order to detect errors
+  ec.clear();
+  if ((dir_entry_ptr = ::readdir(dir_stream)) == nullptr) {
+    if (errno)
+      ec = capture_errno();
+    return {};
+  } else {
+    return {dir_entry_ptr->d_name, get_file_type(dir_entry_ptr, 0)};
+  }
+}
+
+#else // _LIBCPP_WIN32API
+
+static file_type get_file_type(const WIN32_FIND_DATAW& data) {
+  if (data.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT &&
+      data.dwReserved0 == IO_REPARSE_TAG_SYMLINK)
+    return file_type::symlink;
+  if (data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+    return file_type::directory;
+  return file_type::regular;
+}
+static uintmax_t get_file_size(const WIN32_FIND_DATAW& data) {
+  return (static_cast<uint64_t>(data.nFileSizeHigh) << 32) + data.nFileSizeLow;
+}
+static file_time_type get_write_time(const WIN32_FIND_DATAW& data) {
+  ULARGE_INTEGER tmp;
+  const FILETIME& time = data.ftLastWriteTime;
+  tmp.u.LowPart = time.dwLowDateTime;
+  tmp.u.HighPart = time.dwHighDateTime;
+  return file_time_type(file_time_type::duration(tmp.QuadPart));
+}
+
+#endif // !_LIBCPP_WIN32API
 
 } // namespace
 } // end namespace detail
diff --git a/contrib/libs/cxxsupp/libcxx/src/string.cpp b/contrib/libs/cxxsupp/libcxx/src/string.cpp
index 608dcb2c586..3c63f408240 100644
--- a/contrib/libs/cxxsupp/libcxx/src/string.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/string.cpp
@@ -21,6 +21,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
+#ifndef _LIBCPP_ABI_NO_BASIC_STRING_BASE_CLASS
 void __basic_string_common<true>::__throw_length_error() const {
     _VSTD::__throw_length_error("basic_string");
 }
@@ -28,6 +29,7 @@ void __basic_string_common<true>::__throw_length_error() const {
 void __basic_string_common<true>::__throw_out_of_range() const {
     _VSTD::__throw_out_of_range("basic_string");
 }
+#endif
 
 #define _LIBCPP_EXTERN_TEMPLATE_DEFINE(...) template __VA_ARGS__;
 #ifdef _LIBCPP_ABI_STRING_OPTIMIZED_EXTERNAL_INSTANTIATION