bug#31492: 26.1; query-replace-regexp undo fails in regexps w/o printable chars

[Eli Zaretskii]

> From: Tino Calancha <tino.calancha@gmail.com>
> Cc: 31492@debbugs.gnu.org
> Date: Sun, 20 May 2018 20:51:10 +0900
> 
> If the problem arise from using markers istead of integers, then how
> about we just use integers?

Does this work with '^' and 'C-e', if they change text before a match
that was already replaced and recorded?