I agree in the main. This thread looks relevant to pdump concerns. I have
no experience making my own pdumps as some seem to do.

https://lists.gnu.org/archive/html/emacs-devel/2019-01/msg00558.html

On Tue, Sep 17, 2024 at 6:31 PM Spencer Baugh <sbaugh@janestreet.com> wrote:

> Eli Zaretskii <eliz@gnu.org> writes:
>
> >> From: Ship Mints <shipmints@gmail.com>
> >> Date: Tue, 17 Sep 2024 15:22:18 -0400
> >> Cc: sbaugh@janestreet.com, 73318@debbugs.gnu.org, larsi@gnus.org,
> >>      acorallo@gnu.org
> >> I think the kind of "unreliability" in question is, for example, when a
> process starts and unlinks itself. I doubt
> >> Emacs will ever do this. Using the proc file system is "technically"
> unreliable, unable to cover 100% of all
> >> potential cases, but is practically reliable, especially in this case.
> >
> > I don't remember the details, sorry.  You are welcome to look up the
> > past discussions in the archives.  I think they were triggered by look
> > up of the pdumper file, but the results of that are also used by the
> > code which decides where to look for the *.eln files.
>
> I looked up /proc/self/exe in the archives and the only mention is
> https://lists.gnu.org/archive/html/emacs-devel/2019-05/msg00951.html
>
> Gnulib uses /proc/self/exe to provide support for relocatability (in
> progreloc.c).  If it's reliable enough for Gnulib, it should be reliable
> enough for Emacs.
>
> With all due humility, I think I personally am enough of an expert on
> Linux minutiae to say that /proc/self/exe will be substantially more
> reliable than using argv[0].
>
> I can provide a patch to make invocation-directory use /proc/self/exe,
> why don't we just try installing it on master?  If it's worse, we should
> learn soon enough.
>