timevar: use gethrxtime to get wall clock time clock_gettime is not portable. gethrxtime takes the best available option to get the wall clock time, including clock_gettime (monotonic clock), and gettime (non monotonic). Also, using xtime_t instead of float preserves the precision. Suggested by Bruno Haible. * lib/xtime.h (xtime_make): Handle overflows of nanoseconds. * modules/timevar (Depends-on): We need gethrxtime. We no longer use times(). (Link): Update. * lib/timevar.h (timevar_time_def): Use xtime_t. * lib/timevar.c (set_to_current_time): Use gethrxtime. (timevar_print): Instead of checking whether the timings themselves are large enough for the timevar to be printed, check the percentages.