bug#46617: 28.0.50; nativecomp: native compile cache is not invalidated when file is re-byte compiled and changes

[Aaron Jensen]

On Mon, Mar 29, 2021 at 3:15 AM Andrea Corallo <akrl@sdf.org> wrote:
> Compares against the .elc.

For some reason, I do not see this behavior. Touching the elc files
and restarting does not trigger a recompile of the elns.

> Do you have a reproducer I can look at?

Yes, you can follow straight.el's installation instructions. Create a
new .emacs.d/init.el with:

(defvar bootstrap-version)
(let ((bootstrap-file
       (expand-file-name "straight/repos/straight.el/bootstrap.el"
user-emacs-directory))
      (bootstrap-version 5))
  (unless (file-exists-p bootstrap-file)
    (with-current-buffer
        (url-retrieve-synchronously
         
"https://raw.githubusercontent.com/raxod502/straight.el/develop/install.el";
         'silent 'inhibit-cookies)
      (goto-char (point-max))
      (eval-print-last-sexp)))
  (load bootstrap-file nil 'nomessage))

Load emacs, let it install straight and do all native compilation.

Restart emacs. It will recompile straight.el every time you restart.

It will also recompile every time you do:

(load "~/.emacs.d/straight/repos/straight.el/straight.elc" nil
'nomessage 'nosuffix)

One thing of note here is that because of the way straight works there
ends up being two straight.elc files. One in straight/build/straight
and another in straight/repos/straight.el. The former has a
straight.el that symlinks to the latter, but the straight.elcs are
both concrete.

If you attempt to load the one in build, multiple "Compilation
finished." messages get written to the Async-native-compile-log, which
is odd as well:

(load "~/.emacs.d/straight/build/straight/straight.elc" nil 'nomessage
'nosuffix)

Thanks,

Aaron