bug#48925: [PATCH] Set `minibuffer-completion-*` variables buffer-locally in a few more places

[Eli Zaretskii]

> Cc: 48925@debbugs.gnu.org
> Date: Thu, 11 Nov 2021 11:42:34 +0100
> From: miha--- via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> >> To be on the safer side, I guess we could replace the
> >>
> >>     specbind (Qminibuffer_completion_table, Qnil);
> >>
> >> with a use of `minibuffer-with-setup-hook` that sets the var to nil in
> >> the new minibuffer.  But doing it in C is awkward so it would best be
> >> done by moving the function to subr.el.
> >
> > Sounds like a good idea to me.  Miha, could you do that?
> 
> Okay, patch attached.

Moving read-string to subr.el means the function will be unavailable
during loadup until subr.elc is loaded.

What is awkward to do in C?  Maybe I could help with that, so that we
wouldn't need to move this to Lisp.

Thanks.