Re: Bootstrap speed

[Eli Zaretskii]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Sun, 02 Jan 2022 00:44:33 -0500
> 
> With the native compiler, I get the impression that the compilation from
> `.el` to `.elc` files is faster but I also see that we spent an insane
> amount of time in:
> 
>     ELC+ELN  emacs-lisp/macroexp.elc
>     ELC+ELN  emacs-lisp/cconv.elc
>     ELC+ELN  emacs-lisp/byte-opt.elc
>     ELC+ELN  emacs-lisp/bytecomp.elc
>     ELC+ELN  emacs-lisp/comp.elc
>     ELC+ELN  emacs-lisp/comp-cstr.elc
> 
> right after the first dump.

Yes.  See bug#48921.  (comp.el is the worst offender in the above
group.)  Sadly, we didn't make any tangible progress in that matter
since the bug was filed.

> I suspect this can be sped up significantly if we did something like:
> 
>     ELC  emacs-lisp/macroexp.elc
>     ELC  emacs-lisp/cconv.elc
>     ELC  emacs-lisp/byte-opt.elc
>     ELC  emacs-lisp/bytecomp.elc
>     ELC  emacs-lisp/comp.elc
>     ELC  emacs-lisp/comp-cstr.elc
>     ELN  emacs-lisp/macroexp.elc
>     ELN  emacs-lisp/cconv.elc
>     ELN  emacs-lisp/byte-opt.elc
>     ELN  emacs-lisp/bytecomp.elc
>     ELN  emacs-lisp/comp.elc
>     ELN  emacs-lisp/comp-cstr.elc
> 
> Instead.

Please time that (including in parallel builds), maybe it's a good
speedup.  But note that this might require non-trivial changes to the
Makefile's, since the rules we currently use for native compilation
are kludgey workarounds due to the fact that we cannot easily explain
to Make when *.eln files need to be regenerated.