Subject: bug#74438: 29.1; global-mark-ring does not work as described

From: Nikolay Kudryavtsev <[email-masked]>
Date: Wed, 20 Nov 2024 13:18:00 +0300

Emacs won't allow you to set multiple marks in the same position, it's 
just going to activate the current mark. Hence your reproduction recipe 
can be simplified to:

 1. C-x C-f foo
 2. C-SPC => Mark set
 3. C-SPC => Mark deactivated
 4. C-SPC => Mark activated
 5. C-SPC => Mark deactivated
 6. C-SPC => Mark activated

See how you're not getting "Mark set" any time after the first message?

Maybe a couple of sentences should be added to the manual regarding this 
behavior, because mark ring is often a source of confusion for the new 
users.

Also note that the manual recommends you deactivate the mark before 
trying to jump to it:

https://www.gnu.org/software/emacs/manual/html_node/emacs/Setting-Mark.html

"Instead of setting the mark in order to operate on a region, you can 
also use it to remember a position in the buffer (by typing ‘C-<SPC> 
C-<SPC>’), and later jump back there (by typing ‘C-u C-<SPC>’)."