bug#30653: 25.3; crash inside redisplay_internal

[Eli Zaretskii]

> From: "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
> Date: Wed, 28 Feb 2018 08:47:04 -0800
> 
> 
> I am experiencing multiple crashes from Emacs 25.3 on Fedora 27 with XFCE.

It doesn't crash here (but I'm not on that system).

> The crashes happen inside redisplay_internal and when scrolling a window.
> The following recipe causes a crash.  The crash causes X to freeze and then
> dumps me back in a login screen.
> 
> emacs -Q -g 80x65
> control-X control-F tt.text
> control-V
> control-P
> control-shift-,

What does this last key sequence do on your system?

> The kernel log has the following information
> 
>                                               
> Stack trace of thread 2277:
> #0  0x00007f1a35a6198b raise (libpthread.so.0)
> #1  0x00000000004f1254 terminate_due_to_signal (emacs-25.3)
> #2  0x000000000050abb3 emacs_abort (emacs-25.3)
> #3  0x0000000000456002 redisplay_internal (emacs-25.3)
> #4  0x0000000000457115 redisplay_preserve_echo_area (emacs-25.3)
> #5  0x00000000005a2988 Fdelete_process (emacs-25.3)
> #6  0x00000000005aa3e5 kill_buffer_processes (emacs-25.3)
> #7  0x00000000004f1046 shut_down_emacs (emacs-25.3)
> #8  0x00000000004c0cda x_connection_closed (emacs-25.3)
> #9  0x00000000004c0e37 x_io_error_quitter (emacs-25.3)
> #10 0x00007f1a3d70aede _XIOError (libX11.so.6)
> #11 0x00007f1a3d70876d _XEventsQueued (libX11.so.6)
> #12 0x00007f1a3d6fa2bd XPending (libX11.so.6)
> #13 0x00007f1a3f763c2e gdk_event_source_prepare (libgdk-3.so.0)
> #14 0x00007f1a3e0743f9 g_main_context_prepare (libglib-2.0.so.0)
> #15 0x00007f1a3e074dcb g_main_context_iterate.isra.23 (libglib-2.0.so.0)
> #16 0x00007f1a3e074f57 g_main_context_pending (libglib-2.0.so.0)
> #17 0x00007f1a3fc23d1d gtk_events_pending (libgtk-3.so.0)
> #18 0x00000000004c1707 XTread_socket (emacs-25.3)
> #19 0x00000000004f8121 gobble_input (emacs-25.3)
> #20 0x00000000004f8705 process_pending_signals (emacs-25.3)
> #21 0x00000000005a783d wait_reading_process_output (emacs-25.3)

This is not a crash in redisplay_internal, this is a crash due to GTK
closing the connection to the X display.

> See https://bugzilla.redhat.com/attachment.cgi?id=1400957 for more abrt
> output.

I get access denied if I try this URL.