bug#66326: 29.1.50; There should be a way to promote warnings to errors

[Stefan Kangas <stefankangas@gmail.com>]

Eli Zaretskii <eliz@gnu.org> writes:

> More generally, I'm worried by the tendency of people to submit
> patches for Emacs as soon as they find something they think is missing
> in Emacs that they need for some one-time job.  Emacs is not supposed
> to be a huge heap of random features that someone at some time found
> useful for some random job.  Emacs is Free Software: you can easily
> implement this stuff in your local copy and use it as much as you
> want; no need to add that to the Emacs core, unless there's a real
> need for it expressed by enough people, and no better solutions in
> hand.  I do this for my local jobs all the time.

FWIW, I'm generally always in favor of features that make the Emacs Lisp
developers' lives easier, and as much as I appreciate that some users
might want to debug warnings, I don't think I understand the use case(s).

These questions come to mind:

- Are there many warnings during startup?
- Why are they a problem (can't they just be ignored)?
- If some code warns, presumably it's a real issue and should be fixed
  by the user, not in the code.  Otherwise it should be an error.  No?
- Why can't users add an advice to `display-warning' that simply calls
  `error' or somesuch?  Or even just redefine it?

Perhaps this feature would be better as a GNU ELPA package
`debug-warnings' or something like that, so that the community could get
more experience with it.  If it catches on, perhaps we could consider
adding it to core.  Would that way of working make sense?