Re: Enabling hi-res timestamps on Windows

> From: Jeffrey Walton <[email protected]>
> Date: Wed, 19 Feb 2025 09:04:27 -0500
> Cc: Eldred HABERT <[email protected]>, [email protected]
> 
> On Wed, Feb 19, 2025 at 7:41 AM Eli Zaretskii <[email protected]> wrote:
> >
> > It is not that simple.  GNU Make uses 'stat' to retrieve the time
> > stamp of files, and the Windows implementation of 'stat' reports times
> > without hi-res data.  So to define FILE_TIMESTAMP_HI_RES in the native
> > Windows port of GNU Make, someone will need to produce a
> > reimplementation of 'stat' that returns higher-resolution time stamp.
> >
> > Patches are welcome.
> >
> > (The MSYS2 port uses the Cygwin runtime library, whose 'stat' does
> > provide hi-res times.  But the native port cannot use the Cygwin
> > runtime, it must use the native runtime or the Win32 APIs.)
> 
> Another sharp edge is, the hi-res timer on Windows may appear to move
> backwards in time as queries are made on different cores. Also see
> <https://stackoverflow.com/q/44020619>.

Right.  But that's not the hi-res time information I had in mind.  I
meant to use the 0.1 usec resolution of file times, and the
corresponding APIs that return system time with that resolution.
Those do not use the hi-res time described in the above SO article,
and they don't move back, AFAIK.