bug#30874: 27.0.50; Emacs crashes

[Jan Synacek]

On Tue, Mar 20, 2018 at 1:44 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: Jan Synacek <jsynacek@redhat.com>
>> Date: Tue, 20 Mar 2018 13:12:53 +0100
>> Cc: 30874@debbugs.gnu.org
>>
>> > Please show a C-level backtrace from the crash.
>>
>> Since the reproducer is so trivial, I didn't consider it important,
>
> It is always important.  I couldn't reproduce this on my system.
>
>> but there you go (just basic backtrace, the full one is hilariously
>> huge):
>
> Thanks.  Sounds like a duplicate of bug#30045.
>
> Can you run this in X synchronous mode, so that we see which operation
> triggers the original X error?  etc/DEBUG tells how to do that under
> "If you encounter X protocol errors".

I tried the following but it doesn't work:

gdb --args ./src/emacs -Q --eval='(setq x-command-line-resources
"emacs.synchronous: true")' --eval="(switch-to-buffer \"*scratch*\")"
--eval="(insert-char #x274c)" --eval="(set-fontset-font
\"fontset-default\" 'unicode \"Dejavu Sans Mono\")"
--eval="(debug-on-entry 'Fdelete_frame)"

I forgot to mention that this issue is reproducible on the latest
Fedora 27 running gnome and gdm. And as far as I know, I'm not running
wayland.

-- 
Jan Synacek
Software Engineer, Red Hat