A glance over gthr.h reminds me __gthread_time_t. There seem few requirements documented in gthr.h. I discussed this with Adrien Nader on mingw-w64's mailing list a few days ago.
Specifically, here are the two questions: 0) Should __gthread_time_t be a struct or a plain integral type? The 'struct timespec' used by pthread is a struct introduced in POSIX. However my implementation uses a plain uint64_t. 1) How to obtain a __gthread_time_t representing the current time? According to Linux man pages, the timeout parameter of pthread_cond_timedwait() is the same as gettimeofday() - that is, it uses the wall clock. My implementation uses GetTickCount64() - that is, my implementation uses a monotonic clock. Quoting from ISO/IEC WG21 Draft N4582 (C++1z): [quote] 30.4.1.3.1 Class timed_mutex [thread.timedmutex.class] ... template <class Rep, class Period> bool try_lock_for(const chrono::duration<Rep, Period>& rel_time); template <class Clock, class Duration> bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time); ... [/quote] the std::timed_mutex::try_lock_for() function template shall accept any clock type, hence we have to do timestamp translation. It is also important to know how libstdc++ handles this. ------------------ Best regards, lh_mouse 2016-04-18
