1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // UNSUPPORTED: libcpp-has-no-threads 11 // UNSUPPORTED: c++98, c++03, c++11 12 13 // <shared_mutex> 14 15 // template <class Mutex> class shared_lock; 16 17 // void swap(shared_lock& u) noexcept; 18 19 #include <shared_mutex> 20 #include <cassert> 21 22 struct mutex 23 { 24 void lock_shared() {} 25 void unlock_shared() {} 26 }; 27 28 mutex m; 29 30 int main() 31 { 32 std::shared_lock<mutex> lk1(m); 33 std::shared_lock<mutex> lk2; 34 lk1.swap(lk2); 35 assert(lk1.mutex() == nullptr); 36 assert(lk1.owns_lock() == false); 37 assert(lk2.mutex() == &m); 38 assert(lk2.owns_lock() == true); 39 static_assert(noexcept(lk1.swap(lk2)), "member swap must be noexcept"); 40 } 41
