bug#44494: etags.el xref-location-marker does not handle TAGS references to .el.gz files

[Eli Zaretskii]

> From: Pierre Rouleau <prouleau001@gmail.com>
> Date: Sat, 7 Nov 2020 09:15:12 -0500
> Cc: dgutov@yandex.ru, 44494@debbugs.gnu.org
> 
> With both emacs 26.3 and 27.1, iI do:
> . emacs -Q
> . C-x C-f lisp/simple.el
> . C-u M-x cc-require
> ==> message: No definitions found for cc-require
> 
> At this point:
> - the xref backend is the default for .el files; etags.
> - xref-backend-functions is set to (elisp--xref-backend t), a local setting.
> - the abbrev feature is loaded, as M-: (featurep 'abbrev) returns t.
> - So looking for kill-all-abbrevs using the elisp--xref-backend works, my 
>   understanding is that it works because the file that holds the definition 
>   is loaded.

How does this explain the fact that find-tag also worked for me?  Does
it work for you?