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 // <atomic>
13 
14 // struct atomic_flag
15 
16 // void atomic_flag_clear(volatile atomic_flag*);
17 // void atomic_flag_clear(atomic_flag*);
18 
19 #include <atomic>
20 #include <cassert>
21 
main()22 int main()
23 {
24     {
25         std::atomic_flag f = ATOMIC_FLAG_INIT;
26         f.test_and_set();
27         atomic_flag_clear(&f);
28         assert(f.test_and_set() == 0);
29     }
30     {
31         volatile std::atomic_flag f = ATOMIC_FLAG_INIT;
32         f.test_and_set();
33         atomic_flag_clear(&f);
34         assert(f.test_and_set() == 0);
35     }
36 }
37