bug#33091: 27.0.50; Daily+ crashes in auto-save-hook

[Mark A. Hershberger]

Stefan Kangas <stefan@marxist.se> writes:

> Eli Zaretskii <eliz@gnu.org> writes:
>
>>> From: "Mark A. Hershberger" <mah@everybody.org>
>>> Cc: 33091@debbugs.gnu.org
>>> Date: Thu, 18 Oct 2018 16:15:51 -0400
>>>
>>> Eli Zaretskii <eliz@gnu.org> writes:
>>>
>>> > IOW, GC segfaults, and then Emacs tries to auto-save the session,
>>> > which fails.
>>> >
>>> > Is it possible that GC hits a stack overflow?  Can you try manually
>>> > establishing whether that is the case by doing what stack_overflow in
>>> > sysdep.c does?
>>>
>>> I don't know how to do this. I can follow directions if you can tell me
>>> what to do, though.
>>
>> Given the backtrace you show in your report, I believe the commands
>> below should do that:
>>
>>   (gdb) frame 13
>>   (gdb) p/x siginfo->si_addr
>>   (gdb) p/x stack_bottom
>>   (gdb) p/x current_thread->stack_top
>>
>> Stack frame #13 is inside handle_sigsegv, according to your backtrace.
>
> It seems like we need more information from you to make any progress
> here.  Did you have a chance to look into this?

I did, but never followed up here.  It has been a couple of years, but I
may be experiencing this again with emacs built from HEAD.

In the meantime, I have emacs with debugging available, so maybe I can
get some more information from it if I can get something reproducible.

Mark.