bug#70073: 29.3; Emacs-PGTK crashes upon marking some text inside emacs and then middle clicking outside of Emacs

[Eli Zaretskii]

> Date: Fri, 12 Apr 2024 11:54:50 +0200 (CEST)
> From: "Abraham S.A.H." <arash.sah@tuta.io>
> Cc: 70073 <70073@debbugs.gnu.org>
> 
> Sorry for delay.
> 
> I got the opportunity to build Arch's `emacs-wayland` package myself, from 
> the same PKGBUILD file used to build it in Arch's official repositories, 
> including debug and without stripping anything. The result was about 30mg 
> increase in size of the final built Emacs.  And the issue still persist.

The increase of the executable size is because it includes debug info.

> $ gdb emacs
> GNU gdb (GDB) 14.2
> Copyright (C) 2023 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.
> Type "show copying" and "show warranty" for details.
> This GDB was configured as "x86_64-pc-linux-gnu".
> Type "show configuration" for configuration details.
> For bug reporting instructions, please see:
> <https://www.gnu.org/software/gdb/bugs/>.
> Find the GDB manual and other documentation resources online at:
>     <http://www.gnu.org/software/gdb/documentation/>.
> 
> For help, type "help".
> Type "apropos word" to search for commands related to "word"...
> Reading symbols from emacs...
> (gdb) r -Q
> Starting program: /usr/bin/emacs -Q
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/usr/lib/libthread_db.so.1".
> [New Thread 0x7fffeda006c0 (LWP 7410)]
> [New Thread 0x7fffed0006c0 (LWP 7411)]
> [New Thread 0x7fffe7e006c0 (LWP 7412)]
> [New Thread 0x7fffe74006c0 (LWP 7413)]
> [New Thread 0x7fffe6a006c0 (LWP 7414)]
> [New Thread 0x7fffe54006c0 (LWP 7415)]
> [Detaching after vfork from child process 7435]
> 
> Thread 1 "emacs" received signal SIGSEGV, Segmentation fault.
> pgtk_handle_selection_request (event=0x7fffffffbe80)
>     at /usr/src/debug/emacs/emacs-29.3-wayland/src/pgtkselect.c:573
> warning: 573    /usr/src/debug/emacs/emacs-29.3-wayland/src/pgtkselect.c: No 
> such file or directory

At this point, please type at the GDB prompt:

  thread apply all bt

and post the backtrace produced by GDB.  That's the information we
need to try to figure out what causes these crashes.