Re: Enabling native compilation by default when libgccjit is present

[Eli Zaretskii <eliz@gnu.org>]

> From: Michael Heerdegen <michael_heerdegen@web.de>
> Date: Thu, 09 Dec 2021 23:50:55 +0100
> Cc: emacs-devel@gnu.org
> 
> Michael Heerdegen <michael_heerdegen@web.de> writes:
> 
> > Sure, it miscompiles - but it also fails, and a broken eln is never
> > loaded.  Only because of that it "works".
> 
> What I really wanted to do is to point to the fact that the init file is
> a special case.  Will all users be able to fix the warnings so that they
> don't get a broken .eln init file?  Will all of them understand what the
> problem is - when loading the source works without problems?  Compiled
> stuff behaving differently than interpreted code is something that some
> people don't expect and understand.

These questions are supposed to be answered by collecting user
experience and bug reports for Emacs 28.  We don't have that yet, so
we don't know the answers yet.  We still don't know enough about the
various consequences of this new feature in all the different use
patterns out there.

We do know that if your init file is called ".emacs" or "init.el", and
there's no corresponding .elc file, Emacs will NOT natively-compile
the init file.  So at least users who don't byte-compile their init
files are okay (I'm squarely in that group).

> Only programmers would be able to use an Emacs init file.

See above: this is at least inaccurate, if not incorrect.

> I think eln compiling the user's own files should be opt-in.

We will decide on that after we see how the community reacts to the
feature.  For now, I didn't see too many complaints about this on
relevant forums, and a few questions regarding the warnings, when
answered, were met with understanding and "problem solved"
conclusions.  But the jury is still out on these issues, from my POV,
so we will need to revisit these issues later.