bug#50666: 28.0.50; Fix native compilation on Cygwin

[Eli Zaretskii]

> Cc: 50666@debbugs.gnu.org
> Date: Fri, 24 Sep 2021 07:32:11 +0000
> From:  Andrea Corallo via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> > Can you point me to the part of the discussion where it was determined
> > that the absolute location of the file was making a difference that was
> > not covered with the hash of the content?
> 
> Not at the moment sorry, this was discussed more the once in different
> threads in the last 1-2 years.

Right.

One situation that comes to mind is that a .el file could be
native-compiled with different versions of macros in scope, although
that is not necessarily evidenced by the file's absolute name.