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++98, c++03, c++11
11 
12 // <shared_mutex>
13 
14 // template <class Mutex> class shared_lock;
15 
16 // shared_lock();
17 
18 #include <shared_mutex>
19 #include <cassert>
20 
21 int main(int, char**)
22 {
23     std::shared_lock<std::shared_timed_mutex> ul;
24     assert(!ul.owns_lock());
25     assert(ul.mutex() == nullptr);
26 
27   return 0;
28 }
29