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// <condition_variable>
13
14// class condition_variable;
15
16// void wait(unique_lock<mutex>& lock);
17
18#include <condition_variable>
19#include <mutex>
20#include <thread>
21#include <cassert>
22
23std::condition_variable cv;
24std::mutex mut;
25
26int test1 = 0;
27int test2 = 0;
28
29void f()
30{
31    std::unique_lock<std::mutex> lk(mut);
32    assert(test2 == 0);
33    test1 = 1;
34    cv.notify_one();
35    while (test2 == 0)
36        cv.wait(lk);
37    assert(test2 != 0);
38}
39
40int main()
41{
42    std::unique_lock<std::mutex>lk(mut);
43    std::thread t(f);
44    assert(test1 == 0);
45    while (test1 == 0)
46        cv.wait(lk);
47    assert(test1 != 0);
48    test2 = 1;
49    lk.unlock();
50    cv.notify_one();
51    t.join();
52}
53