Re: Skipping installation of .el.gz files

[Spencer Baugh <sbaugh@janestreet.com>]

Eli Zaretskii <eliz@gnu.org> writes:
>> From: Spencer Baugh <sbaugh@janestreet.com>
>> Date: Mon, 23 Oct 2023 12:42:31 -0400
>> 
>> Eli Zaretskii <eliz@gnu.org> writes:
>> >
>> > I suggest to override find-lisp-object-file-name with a similar
>> > definition that does what you want.
>> 
>> Hm, I think what it should do is just, when looking for a Lisp file such
>> as /usr/share/emacs/29.1/lisp/files.elc, if
>> /usr/share/emacs/29.1/lisp/files.el and
>> /usr/share/emacs/29.1/lisp/files.el.gz don't exist, then also check for
>> (concat source-directory "lisp/files.el") and use that if it exists.
>> Only for Lisp files in the Emacs installation directory, of course.
>
> No, because the source directory could hold code different from the
> one which was used to install the files under /usr/share.  Think about
> Emacs installed from a Git repository that got many updates after
> that, for example.

Yes.  And this is an issue today for jumping to the definitions of
functions in C files, since those are not packaged with Emacs.  Today,
that is broken out of the box if source-directory is still around.

So if you think this behavior is bad, then should we fix it to not
happen for the case of C files?  Perhaps by clearing source-directory
when Emacs is installed, so that Emacs cannot find obsolete C files out
of the Git repository?