[Bug libstdc++/63400] [C++11]precision of std::chrono::high_resolution_clock

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63400

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |mingw-w64

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Which of macros are defined on mingw-w64?

Preprocessing this should tell you

#include <chrono>
#ifdef _GLIBCXX_USE_CLOCK_REALTIME
#ifdef _GLIBCXX_USE_CLOCK_GETTIME_SYSCALL
#warning system_clock using syscall(SYS_clock_gettime, CLOCK_REALTIME, &tp);
#else
#warning system_clock using clock_gettime(CLOCK_REALTIME, &tp);
#endif
#elif defined(_GLIBCXX_USE_GETTIMEOFDAY)
#warning system_clock using gettimeofday(&tv, 0);
#else
#warning system_clock using std::time(0);
#endif

#ifdef _GLIBCXX_USE_CLOCK_MONOTONIC
#ifdef _GLIBCXX_USE_CLOCK_GETTIME_SYSCALL
#warning steady_clock using syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &tp);
#else
#warning steady_clock using clock_gettime(CLOCK_MONOTONIC, &tp);
#endif
#else
#warning steady_clock using time_point(system_clock::now().time_since_epoch());
#endif