forked from OSchip/llvm-project
52 lines
1.1 KiB
C++
52 lines
1.1 KiB
C++
//===----------------------------------------------------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is dual licensed under the MIT and the University of Illinois Open
|
|
// Source Licenses. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// UNSUPPORTED: libcpp-has-no-threads
|
|
|
|
// <mutex>
|
|
|
|
// template <class Mutex> class lock_guard;
|
|
|
|
// lock_guard(mutex_type& m, adopt_lock_t);
|
|
|
|
#include <mutex>
|
|
#include <thread>
|
|
#include <cstdlib>
|
|
#include <cassert>
|
|
|
|
std::mutex m;
|
|
|
|
typedef std::chrono::system_clock Clock;
|
|
typedef Clock::time_point time_point;
|
|
typedef Clock::duration duration;
|
|
typedef std::chrono::milliseconds ms;
|
|
typedef std::chrono::nanoseconds ns;
|
|
|
|
void f()
|
|
{
|
|
time_point t0 = Clock::now();
|
|
time_point t1;
|
|
{
|
|
m.lock();
|
|
std::lock_guard<std::mutex> lg(m, std::adopt_lock);
|
|
t1 = Clock::now();
|
|
}
|
|
ns d = t1 - t0 - ms(250);
|
|
assert(d < ms(50)); // within 50ms
|
|
}
|
|
|
|
int main()
|
|
{
|
|
m.lock();
|
|
std::thread t(f);
|
|
std::this_thread::sleep_for(ms(250));
|
|
m.unlock();
|
|
t.join();
|
|
}
|