bug#41239: GTK builds crashing in XTread_socket after deleting a frame

[Eli Zaretskii]

> Cc: 41239@debbugs.gnu.org
> From: martin rudalics <rudalics@gmx.at>
> Date: Fri, 15 May 2020 20:07:57 +0200
> 
> Wouldn't that also block any 'yes-or-no-p' questions we ask when running
> these hooks.  Anyway, it doesn't help.  It crashes as soon as we unblock
> input, for example, thusly

So we need to understand why that crashes.

> tcache_get (tc_idx=0) at malloc.c:2951
> 2951  malloc.c: Datei oder Verzeichnis nicht gefunden.
> (gdb) bt
> #0  0x00007ffff549a7be in tcache_get (tc_idx=0) at malloc.c:2951
> #1  0x00007ffff549a7be in __GI___libc_malloc (bytes=16) at malloc.c:3058

Once again, all the crashes are inside memory-allocation functions,
which suggests some kind of memory corruption.  Did someone try to run
this scenario under valgrind?