10b57cec5SDimitry Andric //===--------------------- mutex_destructor.cpp ---------------------------===//
20b57cec5SDimitry Andric //
30b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
40b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
50b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
60b57cec5SDimitry Andric //
70b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
80b57cec5SDimitry Andric 
90b57cec5SDimitry Andric // Define ~mutex.
100b57cec5SDimitry Andric //
110b57cec5SDimitry Andric // On some platforms ~mutex has been made trivial and the definition is only
120b57cec5SDimitry Andric // provided for ABI compatibility.
130b57cec5SDimitry Andric //
140b57cec5SDimitry Andric // In order to avoid ODR violations within libc++ itself, we need to ensure
150b57cec5SDimitry Andric // that *nothing* sees the non-trivial mutex declaration. For this reason
160b57cec5SDimitry Andric // we re-declare the entire class in this file instead of using
170b57cec5SDimitry Andric // _LIBCPP_BUILDING_LIBRARY to change the definition in the headers.
180b57cec5SDimitry Andric 
190b57cec5SDimitry Andric #include "__config"
200b57cec5SDimitry Andric #include "__threading_support"
210b57cec5SDimitry Andric 
220b57cec5SDimitry Andric #if !defined(_LIBCPP_HAS_NO_THREADS)
230b57cec5SDimitry Andric #if _LIBCPP_ABI_VERSION == 1 || !defined(_LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION)
240b57cec5SDimitry Andric #define NEEDS_MUTEX_DESTRUCTOR
250b57cec5SDimitry Andric #endif
260b57cec5SDimitry Andric #endif
270b57cec5SDimitry Andric 
280b57cec5SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
290b57cec5SDimitry Andric 
300b57cec5SDimitry Andric #ifdef NEEDS_MUTEX_DESTRUCTOR
310b57cec5SDimitry Andric class _LIBCPP_TYPE_VIS mutex
320b57cec5SDimitry Andric {
330b57cec5SDimitry Andric     __libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER;
340b57cec5SDimitry Andric 
350b57cec5SDimitry Andric public:
360b57cec5SDimitry Andric     _LIBCPP_ALWAYS_INLINE _LIBCPP_INLINE_VISIBILITY
370b57cec5SDimitry Andric     constexpr mutex() = default;
380b57cec5SDimitry Andric     mutex(const mutex&) = delete;
390b57cec5SDimitry Andric     mutex& operator=(const mutex&) = delete;
400b57cec5SDimitry Andric     ~mutex() noexcept;
410b57cec5SDimitry Andric };
420b57cec5SDimitry Andric 
430b57cec5SDimitry Andric 
~mutex()44*5f7ddb14SDimitry Andric mutex::~mutex() noexcept
450b57cec5SDimitry Andric {
460b57cec5SDimitry Andric     __libcpp_mutex_destroy(&__m_);
470b57cec5SDimitry Andric }
480b57cec5SDimitry Andric 
490b57cec5SDimitry Andric #endif // !_LIBCPP_HAS_NO_THREADS
500b57cec5SDimitry Andric _LIBCPP_END_NAMESPACE_STD
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