Re: emacs-26 9e59de9: Use GCALIGNED properly for GCC

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 10 Nov 2017 08:10:54 +0100
> From: martin rudalics <rudalics@gmx.at>
> Cc: Paul Eggert <eggert@cs.ucla.edu>
> 
> ... and trying my usual 32-bit build of the release branch on Windows
> currently fails as

Paul, maybe we should simply go back a few notches and not mark
main_thread as GCALIGNED, except on that single platform which needed
it (i.e. via #ifdef)?  Then we could return all the other symbols to
their previous syntax.

Or maybe we should move GCALIGNED to yet another position, like at the
beginning or the end of the whole construct.  Like this:

   GCALIGNED struct foo FOO;
or
   struct foo FOO GCALIGNED;

Not sure what else can we do, but this seems to be an exceptionally
fragile feature, at least with GCC 7 that many people are using.