bug#81407: 31.0.90; Crash in display_line: stale glyph_row after window-config change from menu-bar :enable eval during redisplay

> From: Sean Whitton <[email protected]>
> Cc: [email protected], [email protected], [email protected]
> Date: Sun, 16 Aug 2026 12:25:21 +0100
> 
> unblock 81521 by 81407
> thanks
> 
> Eli Zaretskii [14/Aug  6:25pm +03] wrote:
> >> From: Sean Whitton <[email protected]>
> >> Cc: [email protected], [email protected]
> >> Date: Fri, 14 Aug 2026 16:02:20 +0100
> >>
> >> Eli Zaretskii [14/Aug  5:59pm +03] wrote:
> >> >> From: Sean Whitton <[email protected]>
> >> >> Cc: [email protected], [email protected]
> >> >> Date: Fri, 14 Aug 2026 15:46:00 +0100
> >> >>
> >> >> Eli Zaretskii [14/Aug  5:27pm +03] wrote:
> >> >> > He did? where?
> >> >>
> >> >> In a message to this bug at 1:10pm zulu.
> >> >
> >> > I think this is all a huge misunderstanding.  Alan was never part of
> >> > discussing this bug, and I see the problem on systems other than
> >> > macOS.  The code involved in this was not changed since Emacs 21.
> >>
> >> https://debbugs.gnu.org/81407#46
> >
> > Yes, I've seen it.
> 
> Okay, then, as you say it seems like I am misunderstanding.

As I said, this code is very old.

It is possible, however, that changes we've done in certain
macOS-specific areas of redisplay somehow made this kind of crash much
more probable.  That would explain Alan's observations.

> At the very least it seems like this should not be blocking.

Agreed.