bug#4558: forw_comment slowdown since 22.3

[Lars Ingebrigtsen]

Dan Nicolaescu <dann@ics.uci.edu> writes:

> $ cd emacs/src
>
> $ cat emacs.c emacs.c emacs.c emacs.c emacs.c > /tmp/emacs.c
>
> $ emacs /tmp/emacs.c
> C-x h
> M-;
> C-x C-s
> C-x C-c
>
> $ cat /tmp/t.el
> (defun myfwd ()
>   (interactive)
>   (dotimes (n 1)
>     (while (forward-comment 1))
>     (while (forward-comment -1)))
>   (save-buffers-kill-emacs))
> ;; increase N if your machine is much faster
>
> Now do:
>
> emacs -Q -l /tmp/t.el /tmp/emacs.c -f myfwd

(I'm going through old bug reports that unfortunately didn't get any
response at the time.)

I've tried this in Emacs 27, and it seems quite fast -- much less than a
second.  But, then again, computers are faster now than they were back
when this was reported.  Are you still seeing slow forw_comment in more
modern Emacs versions?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no