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// <thread> -*- C++ -*- |
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// Copyright (C) 2008-2021 Free Software Foundation, Inc. |
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// |
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// This file is part of the GNU ISO C++ Library. This library is free |
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// software; you can redistribute it and/or modify it under the |
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// terms of the GNU General Public License as published by the |
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// Free Software Foundation; either version 3, or (at your option) |
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// any later version. |
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|
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// This library is distributed in the hope that it will be useful, |
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// but WITHOUT ANY WARRANTY; without even the implied warranty of |
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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// GNU General Public License for more details. |
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|
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// Under Section 7 of GPL version 3, you are granted additional |
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// permissions described in the GCC Runtime Library Exception, version |
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// 3.1, as published by the Free Software Foundation. |
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// You should have received a copy of the GNU General Public License and |
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// a copy of the GCC Runtime Library Exception along with this program; |
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
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// <http://www.gnu.org/licenses/>. |
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|
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/** @file include/thread |
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* This is a Standard C++ Library header. |
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*/ |
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#ifndef _GLIBCXX_THREAD |
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#define _GLIBCXX_THREAD 1 |
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#pragma GCC system_header |
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#if __cplusplus < 201103L |
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# include <bits/c++0x_warning.h> |
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#else |
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#if __cplusplus > 201703L |
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# include <compare> // std::strong_ordering |
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# include <stop_token> // std::stop_source, std::stop_token, std::nostopstate |
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#endif |
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#include <bits/std_thread.h> // std::thread, get_id, yield |
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#include <bits/this_thread_sleep.h> // std::this_thread::sleep_for, sleep_until |
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|
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namespace std _GLIBCXX_VISIBILITY(default) |
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{ |
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_GLIBCXX_BEGIN_NAMESPACE_VERSION |
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|
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/** |
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* @defgroup threads Threads |
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* @ingroup concurrency |
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* |
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* Classes for thread support. |
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* @{ |
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*/ |
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// std::thread is defined in <bits/std_thread.h> |
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#if __cpp_lib_three_way_comparison |
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inline strong_ordering |
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operator<=>(thread::id __x, thread::id __y) noexcept |
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{ return __x._M_thread <=> __y._M_thread; } |
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#else |
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inline bool |
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operator!=(thread::id __x, thread::id __y) noexcept |
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{ return !(__x == __y); } |
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|
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inline bool |
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operator<(thread::id __x, thread::id __y) noexcept |
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{ |
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// Pthreads doesn't define any way to do this, so we just have to |
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// assume native_handle_type is LessThanComparable. |
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return __x._M_thread < __y._M_thread; |
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} |
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inline bool |
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operator<=(thread::id __x, thread::id __y) noexcept |
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{ return !(__y < __x); } |
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|
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inline bool |
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operator>(thread::id __x, thread::id __y) noexcept |
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{ return __y < __x; } |
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inline bool |
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operator>=(thread::id __x, thread::id __y) noexcept |
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{ return !(__x < __y); } |
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#endif // __cpp_lib_three_way_comparison |
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|
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template<class _CharT, class _Traits> |
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inline basic_ostream<_CharT, _Traits>& |
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operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id) |
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{ |
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if (__id == thread::id()) |
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return __out << "thread::id of a non-executing thread"; |
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else |
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return __out << __id._M_thread; |
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} |
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#ifdef __cpp_lib_jthread |
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/// A thread that can be requested to stop and automatically joined. |
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class jthread |
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{ |
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public: |
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using id = thread::id; |
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using native_handle_type = thread::native_handle_type; |
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jthread() noexcept |
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: _M_stop_source{nostopstate} |
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{ } |
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template<typename _Callable, typename... _Args, |
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typename = enable_if_t<!is_same_v<remove_cvref_t<_Callable>, |
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jthread>>> |
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explicit |
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jthread(_Callable&& __f, _Args&&... __args) |
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: _M_thread{_S_create(_M_stop_source, std::forward<_Callable>(__f), |
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std::forward<_Args>(__args)...)} |
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{ } |
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jthread(const jthread&) = delete; |
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jthread(jthread&&) noexcept = default; |
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~jthread() |
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{ |
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if (joinable()) |
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{ |
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request_stop(); |
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join(); |
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} |
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} |
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jthread& |
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operator=(const jthread&) = delete; |
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|
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jthread& |
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operator=(jthread&& __other) noexcept |
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{ |
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std::jthread(std::move(__other)).swap(*this); |
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return *this; |
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} |
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|
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void |
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swap(jthread& __other) noexcept |
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{ |
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std::swap(_M_stop_source, __other._M_stop_source); |
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std::swap(_M_thread, __other._M_thread); |
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} |
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[[nodiscard]] bool |
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joinable() const noexcept |
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{ |
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return _M_thread.joinable(); |
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} |
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|
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void |
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join() |
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{ |
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_M_thread.join(); |
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} |
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|
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void |
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detach() |
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{ |
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_M_thread.detach(); |
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} |
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[[nodiscard]] id |
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get_id() const noexcept |
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{ |
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return _M_thread.get_id(); |
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} |
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[[nodiscard]] native_handle_type |
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native_handle() |
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{ |
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return _M_thread.native_handle(); |
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} |
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[[nodiscard]] static unsigned |
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hardware_concurrency() noexcept |
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{ |
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return thread::hardware_concurrency(); |
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} |
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|
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[[nodiscard]] stop_source |
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get_stop_source() noexcept |
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{ |
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return _M_stop_source; |
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} |
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|
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[[nodiscard]] stop_token |
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get_stop_token() const noexcept |
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{ |
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return _M_stop_source.get_token(); |
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} |
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bool request_stop() noexcept |
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{ |
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return _M_stop_source.request_stop(); |
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} |
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friend void swap(jthread& __lhs, jthread& __rhs) noexcept |
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{ |
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__lhs.swap(__rhs); |
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} |
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private: |
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template<typename _Callable, typename... _Args> |
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static thread |
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_S_create(stop_source& __ssrc, _Callable&& __f, _Args&&... __args) |
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{ |
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if constexpr(is_invocable_v<decay_t<_Callable>, stop_token, |
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decay_t<_Args>...>) |
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return thread{std::forward<_Callable>(__f), __ssrc.get_token(), |
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std::forward<_Args>(__args)...}; |
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else |
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{ |
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static_assert(is_invocable_v<decay_t<_Callable>, |
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decay_t<_Args>...>, |
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"std::thread arguments must be invocable after" |
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" conversion to rvalues"); |
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return thread{std::forward<_Callable>(__f), |
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std::forward<_Args>(__args)...}; |
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} |
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} |
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stop_source _M_stop_source; |
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thread _M_thread; |
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}; |
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#endif // __cpp_lib_jthread |
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/// @} group threads |
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_GLIBCXX_END_NAMESPACE_VERSION |
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} // namespace |
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#endif // C++11 |
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#endif // _GLIBCXX_THREAD |
