bug#50268: 28.0.50; Assertion warning during native compilation

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@gmail.com>
> Cc: Lars Ingebrigtsen <larsi@gnus.org>,  Eli Zaretskii <eliz@gnu.org>,  
> 50268@debbugs.gnu.org
> Date: Tue, 21 Sep 2021 13:09:24 -0400
> 
> Mattias Engdegård <mattiase@acm.org> writes:
> 
> > 21 sep. 2021 kl. 18.11 skrev Lars Ingebrigtsen <larsi@gnus.org>:
> >
> >> I did a quick grep through core and GNU ELPA, and I couldn't find any
> >> instances of it being used, so I'd be fine with either solution (i.e.,
> >> either fixing the bug or signalling an error).
> >
> > I know how to fix it but there's no really elegant way of doing it,
> > and unless a convincing case can be made for permitting anonymous
> > &rest, I'd favour disallowing it.
> >
> > Unless I'm mistaken it was Noam who added it
> > (1d47d777ef24c0be9153b0a1c8ba21918fa1025a), so let's ask him.
> 
> It's been a while, but looking at Bug#29165, the reason I added it is
> that it was supported in Emacs 25 and earlier.  Stefan M had some
> justifications there for &optional without variables, but I think they
> don't apply for &rest.

Stefan, can you please chime in?