libcxx/include/__atomic/is_always_lock_free.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef _LIBCPP___ATOMIC_IS_ALWAYS_LOCK_FREE_H
  10 #define _LIBCPP___ATOMIC_IS_ALWAYS_LOCK_FREE_H
  11
  12 #include <__config>
  13
  14 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  15 #  pragma GCC system_header
  16 #endif
  17
  18 _LIBCPP_BEGIN_NAMESPACE_STD
  19
  20 template <class _Tp>
  21 struct __libcpp_is_always_lock_free {
  22   // __atomic_always_lock_free is available in all Standard modes
  23   static const bool __value = __atomic_always_lock_free(sizeof(_Tp), nullptr);
  24 };
  25
  26 _LIBCPP_END_NAMESPACE_STD
  27
  28 #endif // _LIBCPP___ATOMIC_IS_ALWAYS_LOCK_FREE_H