bug#39911: 27.0.90; error in wisent-total-conflicts if no source filename

[Eli Zaretskii <eliz@gnu.org>]

Ping!

> Date: Thu, 05 Mar 2020 11:50:56 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 39911@debbugs.gnu.org
> 
> > From: Neil Okamoto <neil.okamoto@gmail.com>
> > Date: Wed, 4 Mar 2020 09:23:36 -0800
> > 
> > This bug was detected while running docker.el and other packages that depend on tablist [1].  Tablist is an
> > extension of tabulated-list-mode that provides the ability to filter the tabulated list via an expression language. I
> > am not the author of tablist however the author is aware of this issue.
> > 
> > In 27.0.90, tablist is now giving an error when entering its expression editor.  In the debugger I traced the error
> > to wisent-total-conflicts in lisp/cedet/semantic/wisent/comp.el line 2273, in commit
> > 390b4bc1e25fe691548d7ec982eb2f7027fe26a3 [2].  That commit introduced a mechanism to ignore
> > “expected conflicts” via a symbol whose name is constructed on the fly like this:
> > 
> >     (format "wisent-%s--expected-conflicts"
> >                                      (replace-regexp-in-string "\\.el$" "" src)
> > 
> > However, this code doesn’t handle the case where the filename “src” is nil.
> 
> Thank you for your report.
> 
> Lars, could you please look into this?  It's a regression in Emacs 27.
> 
> 
> 
>