Re: New warnings on emacs-26 branch with gcc 8.2.0

[Eli Zaretskii <eliz@gnu.org>]

> From: Paul Eggert <eggert@cs.ucla.edu>
> Date: Sun, 5 Aug 2018 12:56:45 -0700
> 
> > cc1.exe: warning: -Wabi won't warn about anything [-Wabi]
> > cc1.exe: note: -Wabi warns about differences from the most up-to-date ABI, which is also used by default
> > cc1.exe: note: use e.g. -Wabi=11 to warn about changes from GCC 7
> 
> I noticed this problem a while ago on Fedora in several GNU projects, and fixed 
> it for Emacs master in commit 2018-06-30T00:31:04!eggert@cs.ucla.edu.
> 
> To avoid the problem entirely in the emacs-26 I'd run admin/merge-gnulib and 
> update everything from Gnulib as it's not worth the trouble to cherry-pick these 
> sorts of fixes from master. If we'd rather not do admin/merge-gnulib, then we 
> can just suggest './configure --disable-gcc-warnings' and/or 'make 
> WERROR_CFLAGS=' to emacs-26 developers; either of these should work around the 
> problem. (Builders from tarballs needn't worry about this, as GCC warnings are 
> disabled for them by default.)

Since this warning is disabled when building the tarball, I'd like to
avoid excessive changes on its behalf.  Would it make sense instead to
disable -Wabi on emacs-26?  If not, I'd leave these warnings alone.