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// UNSUPPORTED: c++03, c++11, c++14, c++17
11
12// XFAIL: availability-synchronization_library-missing
13
14// <semaphore>
15
16#include <semaphore>
17#include <thread>
18
19#include "make_test_thread.h"
20#include "test_macros.h"
21
22int main(int, char**)
23{
24 std::counting_semaphore<> s(0);
25
26 s.release();
27 s.acquire();
28
29 std::thread t = support::make_test_thread([&](){
30 s.acquire();
31 });
32 s.release(2);
33 t.join();
34 s.acquire();
35
36 return 0;
37}
38

source code of libcxx/test/std/thread/thread.semaphore/release.pass.cpp