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 
12 // <mutex>
13 
14 // template <class Mutex> class unique_lock;
15 
16 // mutex_type* release() noexcept;
17 
18 #include <mutex>
19 #include <cassert>
20 
21 struct mutex
22 {
23     static int lock_count;
24     static int unlock_count;
lockmutex25     void lock() {++lock_count;}
unlockmutex26     void unlock() {++unlock_count;}
27 };
28 
29 int mutex::lock_count = 0;
30 int mutex::unlock_count = 0;
31 
32 mutex m;
33 
main()34 int main()
35 {
36     std::unique_lock<mutex> lk(m);
37     assert(lk.mutex() == &m);
38     assert(lk.owns_lock() == true);
39     assert(mutex::lock_count == 1);
40     assert(mutex::unlock_count == 0);
41     assert(lk.release() == &m);
42     assert(lk.mutex() == nullptr);
43     assert(lk.owns_lock() == false);
44     assert(mutex::lock_count == 1);
45     assert(mutex::unlock_count == 0);
46 }
47