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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// Define ~mutex.
//
// On some platforms ~mutex has been made trivial and the definition is only
// provided for ABI compatibility.
//
// In order to avoid ODR violations within libc++ itself, we need to ensure
// that *nothing* sees the non-trivial mutex declaration. For this reason
// we re-declare the entire class in this file instead of using
// _LIBCPP_BUILDING_LIBRARY to change the definition in the headers.
#include <__config>
#include <__threading_support>
#if _LIBCPP_ABI_VERSION == 1 || !defined(_LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION)
# define NEEDS_MUTEX_DESTRUCTOR
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#ifdef NEEDS_MUTEX_DESTRUCTOR
class _LIBCPP_EXPORTED_FROM_ABI mutex {
__libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER;
public:
_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI constexpr mutex() = default;
mutex(const mutex&) = delete;
mutex& operator=(const mutex&) = delete;
~mutex() noexcept;
};
mutex::~mutex() noexcept { __libcpp_mutex_destroy(&__m_); }
#endif // !NEEDS_MUTEX_DESTRUCTOR
_LIBCPP_END_NAMESPACE_STD
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