Re: Suppressing native compilation (short and long term)

[Eli Zaretskii <eliz@gnu.org>]

> From: Andrea Corallo <akrl@sdf.org>
> Cc: Eli Zaretskii <eliz@gnu.org>, rlb@defaultvalue.org,
>         monnier@iro.umontreal.ca, david@tethera.net, emacs-devel@gnu.org
> Date: Thu, 06 Oct 2022 00:45:49 +0000
> 
> > Which reminds me of another thing -- was there a reason that --batch
> > implies "avoid most JIT compilation", like it does now, by the way?
> > It's always seemed pretty odd to me, because JITting could well be quite
> > useful when doing batch stuff, and there's no handy way to switch it on
> > when doing --batch.
> 
> The rational is that "tipically" batch executions are short in time, so
> spawning there native async compilation would be a waste of cycles if
> they do not complete in time.  I think no one has statistical prove of
> this, but the rational was at least discussed and I believe agreed here.

Yes, we discussed that, and yes, we agreed.  And I don't think the
decision was wrong.  For starters, it would be strange to delay
exiting Emacs in batch so it could wait for the async compilation to
complete.  Moreover, in most cases waiting will not help, since the
job of the batch invocation would have been long done anyway, so the
produced *.eln files will not be loaded in time to make any
difference.

We do have batch commands to compile *.eln files explicitly (this is
used when a release tarball is built).  This was deemed to be enough,
at least at the time we discussed these issues.  I don't yet see why
we'd need to revisit that decision.  When does it cause problems?