Re: Building master fails on Windows 10 when testing etc/NEWS file

[Eli Zaretskii <eliz@gnu.org>]

> Date: Wed, 18 Sep 2019 21:33:10 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: rudalics@gmx.at, emacs-devel@gnu.org
> 
> 		  if (result != 0)                              <<<<<<<<<<<
> 		    found = Fsubstring (found, make_fixnum (0), <<<<<<<<<<<
> 					make_fixnum (-1));      <<<<<<<<<<<
>                 }
> 
> The last 3 lines were added as part of the "improved reporting of I/O
> errors" changeset.  What it does is replace the .elc file name with
> the .el filename if 'stat' fails when called on the .el file.  And in
> installed Emacs we compress *.el files, so they are not there.
> 
> Paul, why was this snippet added?  It makes no sense to me: why should
> we replace an existing .elc file name with a non-existing .el file
> name?

I guess the answer is so that file_test_errno could report the
offending file name...  But the change failed to pay attention that
'found' is used further down.

So based on this hypothesis I fixed the code to not clobber the file
name found by openp.