bug#54450: 29.0.50; redisplay--pre-redisplay-functions issue

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 18 Mar 2022 22:25:24 +0100
> From: Ergus <spacibba@aol.com>
> Cc: 54450@debbugs.gnu.org
> 
> On Fri, Mar 18, 2022 at 08:54:00PM +0200, Eli Zaretskii wrote:
> >> Date: Fri, 18 Mar 2022 20:38:18 +0200
> >> From: Eli Zaretskii <eliz@gnu.org>
> >> Cc: 54450@debbugs.gnu.org
> >>
> >> > Yes, this could solve the issue for the region, but not in general for
> >> > redisplay--update-cursor-face-highlight which was the initial problem
> >> > with Juri's code. Same for any other function that goes into the
> >> > pre-redisplay-functions hook.
> >>
> >> I asked for a test case, and this is what you gave me.
> >>
> >> If there's another test case, please show it.
> >
> >But before you do, please try the alternative patch below:
> >
> >diff --git a/src/xdisp.c b/src/xdisp.c
> >index 5cb5839..6d8d4aa 100644
> >--- a/src/xdisp.c
> >+++ b/src/xdisp.c
> >@@ -13211,7 +13211,8 @@ prepare_menu_bars (void)
> > 	      struct window *w = XWINDOW (this);
> > 	      if (w->redisplay
> > 		  || XFRAME (w->frame)->redisplay
> >-		  || XBUFFER (w->contents)->text->redisplay)
> >+		  || XBUFFER (w->contents)->text->redisplay
> >+		  || w->last_point != marker_position (w->pointm))
> > 		{
> > 		  windows = Fcons (this, windows);
> > 		}
> 
> Yes, now this seems to solve the issue for the two use cases described.

Thanks, I installed a slightly modified variant of this on the
emacs-28 branch.