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-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // UNSUPPORTED: no-threads
10 
11 // <mutex>
12 
13 // template <class Mutex> class unique_lock;
14 
15 // void swap(unique_lock& u);
16 
17 #include <mutex>
18 #include <cassert>
19 
20 #include "test_macros.h"
21 
22 struct mutex
23 {
lockmutex24     void lock() {}
unlockmutex25     void unlock() {}
26 };
27 
28 mutex m;
29 
main(int,char **)30 int main(int, char**)
31 {
32     std::unique_lock<mutex> lk1(m);
33     std::unique_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 
40   return 0;
41 }
42