bug#72759: 31.0.50; Emacs hangs with open-paren-in-column-0-is-defun-start set to nil

[Eli Zaretskii <eliz@gnu.org>]

> From: Eshel Yaron <me@eshelyaron.com>
> Cc: 72759@debbugs.gnu.org
> Date: Fri, 23 Aug 2024 07:54:25 +0200
> 
> Hi Eli,
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> >> diff --git a/lisp/emacs-lisp/checkdoc.el b/lisp/emacs-lisp/checkdoc.el
> >> >> index 949ca6b74ad..65226d8ee44 100644
> >> >> --- a/lisp/emacs-lisp/checkdoc.el
> >> >> +++ b/lisp/emacs-lisp/checkdoc.el
> >> >> @@ -981,7 +981,7 @@ checkdoc-next-docstring
> >> >>  Return nil if there are no more doc strings."
> >> >>    (let (found)
> >> >>      (while (and (not (setq found (checkdoc--next-docstring)))
> >> >> -                (beginning-of-defun -1)))
> >> >> +                (beginning-of-defun-raw -1)))
> >> >>      found))
> 
> > I'm trying to understand what kind of behavior change could be caused
> > by your proposed change, which is why what beginning-of-defun-raw does
> > and beginning-of-defun doesn't is important, especially if some user
> > options can affect that.  E.g., does anything change in this scenario
> > if defun-prompt-regexp is non-nil?
> 
> This change is the correct also when defun-prompt-regexp is non-nil.
> Take a look at beginning-of-defun, it just calls beginning-of-defun-raw
> after possibly pushing a mark, and then it calls beginning-of-line.
> We're not interested in pushing a mark here, neither do we want to move
> back to beginning of the line after each call (that yields an infloop),
> so beginning-of-defun-raw fits the bill precisely.

Thanks, feel free to install this, then.