Update libc++ to a7c2a628 (15 Feb 2022).

Notable changes:
* macros for disabling and enabling compile warnings
* replace _VSTD with std in __ranges
* add stdatomic.h
* implement unreachable()
* implement ranges::rbegin, rend, crbegin and crend
* remove experimental/filesystem header

ref:3104f711bf2401dd8b882290fa4fa01f71924406

10 files changed, 39 insertions, 51 deletions

diff --git a/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h b/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h
index b693476518..4e117c3f19 100644
--- a/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h
+++ b/contrib/libs/cxxsupp/libcxx/src/filesystem/filesystem_common.h
@@ -14,11 +14,11 @@
 #include "chrono"
 #include "climits"
 #include "cstdarg"
-#include "cstdlib"
 #include "ctime"
 #include "filesystem"
 #include "ratio"
 #include "system_error"
+#include <utility>
 
 #if defined(_LIBCPP_WIN32API)
 # define WIN32_LEAN_AND_MEAN
@@ -188,7 +188,7 @@ struct ErrorHandler {
     case 2:
       __throw_filesystem_error(what, *p1_, *p2_, ec);
     }
-    _LIBCPP_UNREACHABLE();
+    __libcpp_unreachable();
   }
 
   _LIBCPP_ATTRIBUTE_FORMAT(__printf__, 3, 0)
@@ -207,7 +207,7 @@ struct ErrorHandler {
     case 2:
       __throw_filesystem_error(what, *p1_, *p2_, ec);
     }
-    _LIBCPP_UNREACHABLE();
+    __libcpp_unreachable();
   }
 
   _LIBCPP_ATTRIBUTE_FORMAT(__printf__, 3, 4)
diff --git a/contrib/libs/cxxsupp/libcxx/src/filesystem/operations.cpp b/contrib/libs/cxxsupp/libcxx/src/filesystem/operations.cpp
index 8e1a8ef1ab..39777a316a 100644
--- a/contrib/libs/cxxsupp/libcxx/src/filesystem/operations.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/filesystem/operations.cpp
@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include <__utility/unreachable.h>
 #include "filesystem"
 #include "array"
 #include "iterator"
@@ -154,7 +155,7 @@ public:
       return makeState(PS_AtEnd);
 
     case PS_AtEnd:
-      _LIBCPP_UNREACHABLE();
+      __libcpp_unreachable();
     }
   }
 
@@ -202,7 +203,7 @@ public:
       return makeState(PS_InRootName, Path.data(), RStart + 1);
     case PS_InRootName:
     case PS_BeforeBegin:
-      _LIBCPP_UNREACHABLE();
+      __libcpp_unreachable();
     }
   }
 
@@ -224,7 +225,7 @@ public:
     case PS_InFilenames:
       return RawEntry;
     }
-    _LIBCPP_UNREACHABLE();
+    __libcpp_unreachable();
   }
 
   explicit operator bool() const noexcept {
@@ -285,7 +286,7 @@ private:
     case PS_AtEnd:
       return getAfterBack();
     }
-    _LIBCPP_UNREACHABLE();
+    __libcpp_unreachable();
   }
 
   /// \brief Return a pointer to the first character in the currently lexed
@@ -302,7 +303,7 @@ private:
     case PS_AtEnd:
       return &Path.back() + 1;
     }
-    _LIBCPP_UNREACHABLE();
+    __libcpp_unreachable();
   }
 
   // Consume all consecutive separators.
@@ -685,7 +686,7 @@ void filesystem_error::__create_what(int __num_paths) {
       return detail::format_string("filesystem error: %s [" PATH_CSTR_FMT "] [" PATH_CSTR_FMT "]",
                                    derived_what, path1().c_str(), path2().c_str());
     }
-    _LIBCPP_UNREACHABLE();
+    __libcpp_unreachable();
   }();
 }
 
@@ -1192,7 +1193,7 @@ bool __fs_is_empty(const path& p, error_code* ec) {
   } else if (is_regular_file(st))
     return static_cast<uintmax_t>(pst.st_size) == 0;
 
-  _LIBCPP_UNREACHABLE();
+  __libcpp_unreachable();
 }
 
 static file_time_type __extract_last_write_time(const path& p, const StatT& st,
@@ -1805,7 +1806,7 @@ path path::lexically_normal() const {
       break;
     }
     case PK_None:
-      _LIBCPP_UNREACHABLE();
+      __libcpp_unreachable();
     }
   }
   // [fs.path.generic]p6.8: If the path is empty, add a dot.
diff --git a/contrib/libs/cxxsupp/libcxx/src/future.cpp b/contrib/libs/cxxsupp/libcxx/src/future.cpp
index 177fe7523e..07ae9389ec 100644
--- a/contrib/libs/cxxsupp/libcxx/src/future.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/future.cpp
@@ -29,13 +29,9 @@ __future_error_category::name() const noexcept
     return "future";
 }
 
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wswitch"
-#elif defined(__GNUC__) || defined(__GNUG__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wswitch"
-#endif
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wswitch")
+_LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wswitch")
 
 string
 __future_error_category::message(int ev) const
@@ -58,11 +54,7 @@ __future_error_category::message(int ev) const
     return string("unspecified future_errc value\n");
 }
 
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#elif defined(__GNUC__) || defined(__GNUG__)
-#pragma GCC diagnostic pop
-#endif
+_LIBCPP_DIAGNOSTIC_POP
 
 const error_category&
 future_category() noexcept
diff --git a/contrib/libs/cxxsupp/libcxx/src/hash.cpp b/contrib/libs/cxxsupp/libcxx/src/hash.cpp
index b8e921ad06..daf276f5b7 100644
--- a/contrib/libs/cxxsupp/libcxx/src/hash.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/hash.cpp
@@ -11,9 +11,7 @@
 #include "stdexcept"
 #include "type_traits"
 
-#ifdef __clang__
-#pragma clang diagnostic ignored "-Wtautological-constant-out-of-range-compare"
-#endif
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wtautological-constant-out-of-range-compare")
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/src/include/ryu/d2s_intrinsics.h b/contrib/libs/cxxsupp/libcxx/src/include/ryu/d2s_intrinsics.h
index 95912818ac..756fe1e831 100644
--- a/contrib/libs/cxxsupp/libcxx/src/include/ryu/d2s_intrinsics.h
+++ b/contrib/libs/cxxsupp/libcxx/src/include/ryu/d2s_intrinsics.h
@@ -46,6 +46,8 @@
 
 #include "include/ryu/ryu.h"
 
+#include "include/ryu/ryu.h"
+
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 #if defined(_M_X64) && defined(_MSC_VER)
diff --git a/contrib/libs/cxxsupp/libcxx/src/include/ryu/ryu.h b/contrib/libs/cxxsupp/libcxx/src/include/ryu/ryu.h
index 78c04e81ab..cfd5303472 100644
--- a/contrib/libs/cxxsupp/libcxx/src/include/ryu/ryu.h
+++ b/contrib/libs/cxxsupp/libcxx/src/include/ryu/ryu.h
@@ -68,7 +68,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 // https://github.com/ulfjack/ryu/tree/59661c3/ryu
 
-#if !defined(_LIBCPP_COMPILER_MSVC)
+#if !defined(_MSC_VER)
 _LIBCPP_HIDE_FROM_ABI inline unsigned char _BitScanForward64(unsigned long* __index, unsigned long long __mask) {
   if (__mask == 0) {
     return false;
@@ -84,7 +84,7 @@ _LIBCPP_HIDE_FROM_ABI inline unsigned char _BitScanForward(unsigned long* __inde
   *__index = __builtin_ctz(__mask);
   return true;
 }
-#endif  // _LIBCPP_COMPILER_MSVC
+#endif  // !_MSC_VER
 
 template <class _Floating>
 [[nodiscard]] to_chars_result _Floating_to_chars_ryu(
diff --git a/contrib/libs/cxxsupp/libcxx/src/locale.cpp b/contrib/libs/cxxsupp/libcxx/src/locale.cpp
index c9ecfb24ff..92fd8d7445 100644
--- a/contrib/libs/cxxsupp/libcxx/src/locale.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/locale.cpp
@@ -12,6 +12,8 @@
 #define _LCONV_C99
 #endif
 
+#include <__utility/unreachable.h>
+#include "algorithm"
 #include "clocale"
 #include "codecvt"
 #include "cstdio"
@@ -46,9 +48,7 @@
 
 // On Linux, wint_t and wchar_t have different signed-ness, and this causes
 // lots of noise in the build log, but no bugs that I know of.
-#if defined(__clang__)
-#pragma clang diagnostic ignored "-Wsign-conversion"
-#endif
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wsign-conversion")
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
@@ -4641,7 +4641,7 @@ static bool checked_string_to_char_convert(char& dest,
 
   return false;
 #endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
-  _LIBCPP_UNREACHABLE();
+  __libcpp_unreachable();
 }
 
 
@@ -5218,12 +5218,8 @@ __time_get::~__time_get()
 {
     freelocale(__loc_);
 }
-#if defined(__clang__)
-#pragma clang diagnostic ignored "-Wmissing-field-initializers"
-#endif
-#if defined(__GNUG__)
-#pragma GCC   diagnostic ignored "-Wmissing-field-initializers"
-#endif
+
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wmissing-field-initializers")
 
 template <>
 string
@@ -5369,9 +5365,7 @@ __time_get_storage<char>::__analyze(char fmt, const ctype<char>& ct)
     return result;
 }
 
-#if defined(__clang__)
-#pragma clang diagnostic ignored "-Wmissing-braces"
-#endif
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wmissing-braces")
 
 #ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
 template <>
diff --git a/contrib/libs/cxxsupp/libcxx/src/strstream.cpp b/contrib/libs/cxxsupp/libcxx/src/strstream.cpp
index e62c07768b..fe7e2d4120 100644
--- a/contrib/libs/cxxsupp/libcxx/src/strstream.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/strstream.cpp
@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include <__utility/unreachable.h>
 #include "strstream"
 #include "algorithm"
 #include "climits"
@@ -268,7 +269,7 @@ strstreambuf::seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmod
             newoff = seekhigh - eback();
             break;
         default:
-            _LIBCPP_UNREACHABLE();
+            __libcpp_unreachable();
         }
         newoff += __off;
         if (0 <= newoff && newoff <= seekhigh - eback())
diff --git a/contrib/libs/cxxsupp/libcxx/src/support/win32/locale_win32.cpp b/contrib/libs/cxxsupp/libcxx/src/support/win32/locale_win32.cpp
index 43e5c9a572..67f4d1341a 100644
--- a/contrib/libs/cxxsupp/libcxx/src/support/win32/locale_win32.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/support/win32/locale_win32.cpp
@@ -97,10 +97,10 @@ int snprintf_l(char *ret, size_t n, locale_t loc, const char *format, ...)
         ret, n, format, loc, ap);
 #else
     __libcpp_locale_guard __current(loc);
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wformat-nonliteral"
+    _LIBCPP_DIAGNOSTIC_PUSH
+    _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wformat-nonliteral")
     int result = vsnprintf( ret, n, format, ap );
-#pragma clang diagnostic pop
+    _LIBCPP_DIAGNOSTIC_POP
 #endif
     va_end(ap);
     return result;
diff --git a/contrib/libs/cxxsupp/libcxx/src/support/win32/support.cpp b/contrib/libs/cxxsupp/libcxx/src/support/win32/support.cpp
index 6d4b371f3d..dbec4083cb 100644
--- a/contrib/libs/cxxsupp/libcxx/src/support/win32/support.cpp
+++ b/contrib/libs/cxxsupp/libcxx/src/support/win32/support.cpp
@@ -23,10 +23,10 @@ int __libcpp_vasprintf( char **sptr, const char *__restrict format, va_list ap )
     // Query the count required.
     va_list ap_copy;
     va_copy(ap_copy, ap);
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wformat-nonliteral"
+    _LIBCPP_DIAGNOSTIC_PUSH
+    _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wformat-nonliteral")
     int count = vsnprintf( NULL, 0, format, ap_copy );
-#pragma clang diagnostic pop
+    _LIBCPP_DIAGNOSTIC_POP
     va_end(ap_copy);
     if (count < 0)
         return count;
@@ -36,10 +36,10 @@ int __libcpp_vasprintf( char **sptr, const char *__restrict format, va_list ap )
         return -1;
     // If we haven't used exactly what was required, something is wrong.
     // Maybe bug in vsnprintf. Report the error and return.
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wformat-nonliteral"
+    _LIBCPP_DIAGNOSTIC_PUSH
+    _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wformat-nonliteral")
     if (vsnprintf(p, buffer_size, format, ap) != count) {
-#pragma clang diagnostic pop
+    _LIBCPP_DIAGNOSTIC_POP
         free(p);
         return -1;
     }