Subject: Re: bug#79200: 31.0.50; Duplicated elements for '#<marker at' in buffer-undo-list

From: Óscar Fuentes <[email-masked]>
Date: Sat, 09 Aug 2025 11:47:21 +0200

Eli Zaretskii <[email-masked]> writes:

> Your bug report says this is on master branch:
>
>> In GNU Emacs 31.0.50 (build 1, x86_64-pc-linux-gnu, X toolkit, cairo
>>  version 1.18.4) of 2025-08-08 built on zen
>> Repository revision: 12354bcfdc288f111c411c87e8bdebe6dcb41a4d
>> Repository branch: master
>
> But I can only reproduce this on the igc branch.  On master, I see a
> single entry for marker adjustment, not many identical ones.

On master you need more elaborate sequences of typing, undoing and
redoing, but it is definitively reproducible.

Maybe it is easier on igc because it does not do compactation, as Pip
noted.

Also tried your suggestion of calling garbage-collect (on master) before
looking at buffer-undo-list. The sequences of duplicated elements
remained.