bug#11604: USE_LISP_UNION_TYPE + USE_LSB_TAG cleanup.

[Eli Zaretskii]

> Date: Sat, 02 Jun 2012 23:50:07 -0700
> From: Paul Eggert <eggert@cs.ucla.edu>
> CC: 11604@debbugs.gnu.org
> 
> >> +  (union Lisp_Object): Don't worry about WORDS_BIGENDIAN; the
> >> +  code works fine either way, and efficiency is not a concern here.
> >
> > why isn't efficiency a concern?
> 
> Because the union type is for debugging, not for production.

I didn't know that.  If that is so, it should be mentioned in the
comments somewhere.  (I actually thought that Stefan wants to move to
that model for production at some point, but maybe I misunderstood.)

> > Also, which parts of gnulib make 'static inline' portable?  If it
> > isn't in a part that is used by the MS-Windows port, the MSVC build is
> > still being screwed by these changes.
> 
> Mostly, it's the AC_C_INLINE stuff in m4/*.

Yes, but where in the gnulib stuff that is compiled does it make
'static inline' portable?  The m4/* files aren't used for compiling
and linking, so that's not the answer I was looking for.

> 'static inline' been used for some time in Emacs, and it works just
> fine with the MSVC build.

I believe you, but I'd like still to make sure I understand all the
aspects of this.