bug#36566: 27.0.50; debug is sometimes horribly slow

[Lars Ingebrigtsen]

Gemini Lasswell <gazally@runbox.com> writes:

> The slowness does come from printing large tree-like structures. Here is
> a small example to reproduce the problem.  Paste the following code into
> *scratch*:
>
> (defun my-make-a-tree (depth)
>   (if (natnump depth)
>       (list (my-make-a-tree (1- depth)) (my-make-a-tree (1- depth)))
>     (list 'leaf)))
>
> (defun my-func ()
>   (let ((tree (my-make-a-tree 13)))
>     tree))
>
> (my-func)
>
> Evaluate the first form using C-M-x and the second using C-u C-M-x.
> Then evaluate the third form with C-M-x.  You will enter Edebug; press
> space to step through.
>
> Result: Each step takes a few seconds and creates a message of about
> 150K characters.

Thanks for the recipe; I can reproduce the issue here, too.  I'm not
quite sure what the correct shortening would be here...  anybody got any
ideas?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no