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: libcpp-has-no-threads
10 // UNSUPPORTED: c++03, c++11
11 
12 // This test requires the dylib support introduced in D68480, which shipped in macOS 11.0.
13 // XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14|15}}
14 
15 // TODO(ldionne): This test fails on Ubuntu Focal on our CI nodes (and only there), in 32 bit mode.
16 // UNSUPPORTED: linux && 32bits-on-64bits
17 
18 // <semaphore>
19 
20 #include <cassert>
21 #include <semaphore>
22 #include <thread>
23 
24 #include "make_test_thread.h"
25 #include "test_macros.h"
26 
27 int main(int, char**)
28 {
29   std::counting_semaphore<> s(1);
30 
31   assert(s.try_acquire());
32   assert(!s.try_acquire());
33   s.release();
34   assert(s.try_acquire());
35   assert(!s.try_acquire());
36   s.release(2);
37   std::thread t = support::make_test_thread([&](){
38     assert(s.try_acquire());
39   });
40   t.join();
41   assert(s.try_acquire());
42   assert(!s.try_acquire());
43 
44   return 0;
45 }
46