Re: Why is it so difficult to get a Lisp backtrace?

[Eli Zaretskii]

> Date: Sat, 25 Jun 2022 15:59:52 +0000
> Cc: emacs-devel@gnu.org
> From: Alan Mackenzie <acm@muc.de>
> 
> Another thing I'd like to be able to do is get a backtrace when there's
> an error in font-locking during redisplay.  That's a whole order of
> magnitude difference in complexity.

The only two ways of having that, AFAIK, are:

  . emit the backtrace int *Messages*
  . add the backtrace to delayed-warnings-list

You _cannot_ have a *backtrace* buffer popping up when the error comes
from some Lisp called by redisplay, because we explicitly disable
that, and for a good reason.