bug#50934: 28.0.60; paren.el should be preloaded

[Eli Zaretskii <eliz@gnu.org>]

> Date: Sat, 02 Oct 2021 11:13:45 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 50934@debbugs.gnu.org
> 
> > From: Andrea Corallo <akrl@sdf.org>
> > Cc: 50934@debbugs.gnu.org
> > Date: Fri, 01 Oct 2021 13:35:57 +0000
> > 
> > > The native-compilation build is already painfully slow, and most of it
> > > isn't spent in COMPILE_FIRST.  We could, of course, add those files to
> > > shortlisp instead, if you think this is better.
> > 
> > I suspect shortlisp might be a better option (the number of threads of
> > the machine here comes into play as well), but I guess a measure is the
> > only way to get an answer.  IOW just wanted to raise the warning.
> 
> I tried to add these to shortlisp, after the value is exported as
> $LISP_PRELOADED, but that didn't work: the added files were only
> byte-compiled, not ELC+ELN-compiled.  I cannot figure out why this
> happens.  I think this mystery should be resolved, so we would know
> how to add files to AOT native compilation without adding them to
> COMPILE_FIRST and without putting them into preloaded/.  I also cannot
> figure out how come some files not mentioned in shortlisp end up being
> ELC+ELN-compiled (for example emoji-zwj.el), also something that's
> worth understanding.
> 
> For now, I just added those files to COMPILE_FIRST.

The problem is solved, so I'm marking the bug done.