44 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8//9// UNSUPPORTED: no-threads10// UNSUPPORTED: c++03, c++1111 12// <shared_mutex>13 14// template <class Mutex> class shared_lock;15 16// void swap(shared_lock& u) noexcept;17 18#include <shared_mutex>19#include <cassert>20 21#include "test_macros.h"22 23struct mutex24{25 void lock_shared() {}26 void unlock_shared() {}27};28 29mutex m;30 31int main(int, char**)32{33 std::shared_lock<mutex> lk1(m);34 std::shared_lock<mutex> lk2;35 lk1.swap(lk2);36 assert(lk1.mutex() == nullptr);37 assert(lk1.owns_lock() == false);38 assert(lk2.mutex() == &m);39 assert(lk2.owns_lock() == true);40 static_assert(noexcept(lk1.swap(lk2)), "member swap must be noexcept");41 42 return 0;43}44