https://bugs.winehq.org/show_bug.cgi?id=57035
--- Comment #2 from LIU Hao lh_mouse@126.com ---
Both are very well within the margin or error, sleeps are never perfectly accurate.
Is there an actual error this causes?
No. I have implemented timed mutex, condition variable, and sleep functions that rely on such behavior, and my tests start to fail since Wine 9.0 because of this.
Not sure about Windows though, let's take POSIX for example: (https://pubs.opengroup.org/onlinepubs/9699919799/functions/clock_nanosleep.h...)
DESCRIPTION (p3) The suspension time caused by this function may be longer than requested because the argument value is rounded up to an integer multiple of the sleep resolution, ...
So if a 'sleep resolution' (schduling gradularity, I suspect) exists, the timeout shall be rounded up, and the suspension may be longer than requested; in no case shall it be shorter.
Also see message of https://github.com/mingw-w64/mingw-w64/commit/52f2ce12c6182bd239e4f1bbffcd42...