bug#63283: Emacs crash within fontset

[Eli Zaretskii]

[Please use Reply All to reply, so that the bug address is on the CC
list, and this discussion is recorded by our bug tracker.]

> Date: Fri, 05 May 2023 21:19:18 +0000
> From: Seppo Ronkainen <sodr80@protonmail.com>
> 
> I was not aware about report-emacs-bug   thanks for the guidance
> 
> Following instructions from (share/emacs/29.0.90/etc/DEBUG:19) I rebuilt with 
> options
> 
>   ./configure --enable-checking='yes,glyphs' --enable-check-lisp-object-type \
>     CFLAGS='-O0 -g3'
> 
> 
> 
> TL;DR
> Now it looks as if (of course) Emacs never crashed, but it seems as if 
> insufficient font data caused an abort is that right? Hope this helps
> 
> fontset.c:970: Emacs fatal error: assertion failed: fontset_id_valid_p 
> (face->fontset)
> Fatal error 6: Aborted

Thanks, but this is not enough info to find the root cause of the
problem.  Please run Emacs under GDB, like this:

  $ gdb /path/to/src/emacs
  ...
  (gdb) run

Then, when Emacs crashes or aborts, GDB will kick in and show its
"(gdb)" prompt.  Please type at the GDB prompt:

  (gdb) thread apply all bt

and post here everything that GDB prints in response.

Also, please show what this displays inside Emacs built --without-all:

  M-: system-configuration-features RET