boost::mutex m;

#if defined BOOST_THREAD_USES_CHRONO

typedef boost::chrono::high_resolution_clock Clock;
typedef Clock::time_point time_point;
typedef Clock::duration duration;
typedef boost::chrono::milliseconds ms;
typedef boost::chrono::nanoseconds ns;
time_point t0;
time_point t1;
#else
#endif

const ms max_diff(BOOST_THREAD_TEST_TIME_MS);

void f()
{
#if defined BOOST_THREAD_USES_CHRONO
  t0 = Clock::now();
  {
#if ! defined(BOOST_NO_CXX11_AUTO_DECLARATIONS)
  auto
#else
  boost::unique_lock<boost::mutex>
#endif
    //&&
    _ = boost::make_unique_lock(m); (void)_;
    t1 = Clock::now();
  }
#else
  //time_point t0 = Clock::now();
  //time_point t1;
  {
#if ! defined(BOOST_NO_CXX11_AUTO_DECLARATIONS)
  auto
#else
  boost::unique_lock<boost::mutex>
#endif
  //&&
  _ = boost::make_unique_lock(m); (void)_;
    //t1 = Clock::now();
  }
  //ns d = t1 - t0 - ms(250);
  //BOOST_TEST(d < max_diff);
#endif
}

int main()
{
  m.lock();
  boost::thread t(f);
#if defined BOOST_THREAD_USES_CHRONO
  time_point t2 = Clock::now();
  boost::this_thread::sleep_for(ms(250));
  time_point t3 = Clock::now();
#else
#endif
  m.unlock();
  t.join();

#if defined BOOST_THREAD_USES_CHRONO
  ns sleep_time = t3 - t2;
  ns d_ns = t1 - t0 - sleep_time;
  ms d_ms = boost::chrono::duration_cast<boost::chrono::milliseconds>(d_ns);
  // BOOST_TEST_GE(d_ms.count(), 0);
  BOOST_THREAD_TEST_IT(d_ms, max_diff);
  BOOST_THREAD_TEST_IT(d_ns, ns(max_diff));
#endif

  return boost::report_errors();
}
//#else
//int main()
//{
//  return boost::report_errors();
//}
//#endif

