libstdc++-v3/src/c++11/compatibility-condvar.cc

   1 // Compatibility symbols for previous versions, C++0x bits -*- C++ -*-
   2
   3 // Copyright (C) 2013-2024 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 #include <bits/c++config.h>
  26
  27 #if __cplusplus < 201103L
  28 # error "compatibility-condvar-c++0x.cc must be compiled with -std=gnu++11"
  29 #endif
  30
  31 #if _GLIBCXX_INLINE_VERSION
  32 # error "compatibility-thread-c++0x.cc is not needed for gnu-versioned-namespace"
  33 #endif
  34
  35 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
  36
  37 #define condition_variable_any condition_variable_anyXX
  38 #include <condition_variable>
  39 #undef condition_variable_any
  40
  41 // XXX GLIBCXX_ABI Deprecated
  42 // gcc-4.9.0
  43 // std::condition_variable_any replaced with std::_V2::condition_variable_any
  44 namespace std _GLIBCXX_VISIBILITY(default)
  45 {
  46 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  47   class condition_variable_any
  48   {
  49     condition_variable                  _M_cond;
  50     mutex                               _M_mutex;
  51
  52   public:
  53     condition_variable_any() noexcept;
  54     ~condition_variable_any() noexcept;
  55   };
  56   condition_variable_any::condition_variable_any() noexcept = default;
  57   condition_variable_any::~condition_variable_any() noexcept = default;
  58 _GLIBCXX_END_NAMESPACE_VERSION
  59 } // namespace std
  60
  61 #if ! _GLIBCXX_INLINE_VERSION
  62 // XXX GLIBCXX_ABI Deprecated
  63 // gcc-12.1
  64 // std::condition_variable::wait changed to noexcept(false)
  65 #if defined(_GLIBCXX_SYMVER_GNU) && defined(_GLIBCXX_SHARED) \
  66     && defined(_GLIBCXX_HAVE_AS_SYMVER_DIRECTIVE) \
  67     && defined(_GLIBCXX_HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
  68 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
  69 {
  70 namespace
  71 {
  72   // Pointer-to-member for private std::condition_variable::_M_cond member.
  73   std::__condvar std::condition_variable::* __base_member;
  74
  75   template<std::__condvar std::condition_variable::*X>
  76     struct cracker
  77     { static std::__condvar std::condition_variable::* value; };
  78
  79   // Initializer for this static member also initializes __base_member.
  80   template<std::__condvar std::condition_variable::*X>
  81     std::__condvar std::condition_variable::*
  82       cracker<X>::value = __base_member = X;
  83
  84   // Explicit instantiation is allowed to access the private member.
  85   template class cracker<&std::condition_variable::_M_cond>;
  86 }
  87
  88 struct __nothrow_wait_cv : std::condition_variable
  89 {
  90   void wait(std::unique_lock<std::mutex>&) noexcept;
  91 };
  92
  93 __attribute__((used))
  94 void
  95 __nothrow_wait_cv::wait(std::unique_lock<std::mutex>& lock) noexcept
  96 {
  97   // In theory this could be simply this->std::condition_variable::wait(lock)
  98   // but with uclibc that binds to the @GLIBCXX_3.4.11 symbol, see PR 105730.
  99   (this->*__base_member).wait(*lock.mutex());
 100 }
 101 } // namespace __gnu_cxx
 102
 103 // Export a noexcept wrapper around std::condition_variable::wait
 104 // with the original @GLIBCXX_3.4.11 symbol version.
 105 asm(
 106   ".symver _ZN9__gnu_cxx17__nothrow_wait_cv4waitERSt11unique_lockISt5mutexE,"
 107   "_ZNSt18condition_variable4waitERSt11unique_lockISt5mutexE@GLIBCXX_3.4.11"
 108 );
 109 #endif
 110 #endif
 111
 112 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1