bug#71774: 31.0.50; Hash table weakness broken?

[Pip Cet]

On Tuesday, June 25th, 2024 at 13:57, martin rudalics via "Bug reports for GNU 
Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org> wrote:
> With Emacs -Q evaluate the following forms in scratch step by step:
> 
> 
> (defvar table (make-hash-table :weakness t))
> 
> (puthash t (split-window) table)
> 
> (delete-other-windows)
> 
> (garbage-collect)
> 
> (gethash t table)

Is it possible the problem is fixed by running (setq values nil) before 
(garbage-collect), or after it, or in between calls to (garbage-collect)? I've 
not had time to test on current emacs -Q, but on my running emacs session that 
appears to fix the problem.

Of course I have no idea why it worked differently in older emacs versions.

Pip