bug#55672: 29.0.50; Emacs crashes when calling start-process-shell-command xdg-open with process-connection-type set to nil

[Ihor Radchenko]

Po Lu <luangruo@yahoo.com> writes:

> Please follow the instructions in the file etc/DEBUG on debugging X
> errors, and show a complete backtrace (type "bt" at the gdb prompt).

> Unless the error happens at a very early stage of display setup, you
> should run Emacs with "-q -xrm Emacs.synchronous: true", to ensure that
> X errors are reported immediately after the call that caused them,
> instead of at the next synchronization point.

Note that it is the first time I am using GDB. I appreciate the
guidance.

Following your latest instructions:

> gdb --args ./emacs -Q -xrm 'Emacs.synchronous: true' -l ~/bug.el
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Reading symbols from ./emacs...
SIGINT is used by the debugger.
Are you sure you want to change it? (y or n) [answered Y; input not from 
terminal]
DISPLAY = :0
TERM = xterm-kitty
Breakpoint 1 at 0x2083b5: file emacs.c, line 420.
Breakpoint 2 at 0x1cc1d1: file xterm.c, line 21573.
(gdb) run
Starting program: /home/yantar92/Git/emacs/src/emacs -Q -xrm 
Emacs.synchronous:\ true -l /home/yantar92/bug.el
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 0x7ffff049d640 (LWP 25230)]
[Detaching after vfork from child process 25399]

[Detaching after vfork from child process 25801]
[Detaching after vfork from child process 25996]

Thread 1 "emacs" hit Breakpoint 2, x_error_quitter (display=0x5555562ffee0, 
event=0x7fffffffa150) at xterm.c:21573
21573   {
(gdb) 
(gdb) bt
#0  x_error_quitter (display=0x5555562ffee0, event=0x7fffffffa150) at 
xterm.c:21573
#1  0x00005555557201b1 in x_error_handler (display=0x5555562ffee0, 
event=0x7fffffffa150) at xterm.c:21561
#2  0x00007ffff7ca3947 in _XError () at /usr/lib64/libX11.so.6
#3  0x00007ffff7ca03e7 in  () at /usr/lib64/libX11.so.6
#4  0x00007ffff7ca0cda in _XEventsQueued () at /usr/lib64/libX11.so.6
#5  0x00007ffff7ca4195 in _XGetRequest () at /usr/lib64/libX11.so.6
#6  0x00007ffff7c99e20 in _XSetClipRectangles () at /usr/lib64/libX11.so.6
#7  0x00007ffff7c9a00e in XSetClipRectangles () at /usr/lib64/libX11.so.6
#8  0x00005555556fcf2a in x_set_clip_rectangles (f=0x555556bd6028, 
gc=0x5555560142a0, rectangles=0x7fffffffa4c0, n=1) at xterm.c:5136
#9  0x000055555570312a in x_draw_relief_rect
    (f=0x555556bd6028, left_x=36, top_y=15, right_x=69, bottom_y=50, hwidth=1, 
vwidth=1, raised_p=true, top_p=true, bot_p=true, left_p=false, right_p=false, 
clip_rect=0x7fffffffa4c0)
    at xterm.c:7832
#10 0x0000555555703b5d in x_draw_glyph_string_box (s=0x7fffffffb0b0) at 
xterm.c:8118
#11 0x0000555555705550 in x_draw_glyph_string (s=0x7fffffffb0b0) at xterm.c:8955
#12 0x000055555563709d in draw_glyphs (w=0x55555c11a420, x=373, 
row=0x5555562a3ca0, area=TEXT_AREA, start=0, end=13, hl=DRAW_NORMAL_TEXT, 
overlaps=0) at xdisp.c:29917
#13 0x000055555563ea1b in gui_write_glyphs (w=0x55555c11a420, 
updated_row=0x5555562a3ca0, start=0x55555e131de0, updated_area=TEXT_AREA, 
len=13) at xdisp.c:31951
#14 0x00005555555a207e in update_text_area (w=0x55555c11a420, 
updated_row=0x5555562a3ca0, vpos=0, partial_p=0x7fffffffb67d) at dispnew.c:3944
#15 0x00005555555a2c09 in update_window_line (w=0x55555c11a420, vpos=0, 
mouse_face_overwritten_p=0x7fffffffb6c8) at dispnew.c:4202
#16 0x00005555555a13ad in update_window (w=0x55555c11a420, force_p=true) at 
dispnew.c:3682
#17 0x00005555555a02b7 in update_frame (f=0x555556bd6028, force_p=true, 
inhibit_hairy_id_p=false) at dispnew.c:3229
#18 0x000055555560274f in redisplay_internal () at xdisp.c:16675
#19 0x0000555555603358 in redisplay_preserve_echo_area (from_where=12) at 
xdisp.c:16944
#20 0x00005555558eca26 in wait_reading_process_output (time_limit=30, nsecs=0, 
read_kbd=-1, do_display=true, wait_for_cell=XIL(0), wait_proc=0x0, 
just_wait_proc=0) at process.c:5834
#21 0x00005555555a9238 in sit_for (timeout=make_fixnum(30), reading=true, 
display_option=1) at dispnew.c:6201
#22 0x000055555576a803 in read_char (commandflag=1, map=XIL(0x55555625bf23), 
prev_event=XIL(0), used_mouse_menu=0x7fffffffd3bd, end_time=0x0) at 
keyboard.c:2835
#23 0x0000555555780154 in read_key_sequence
    (keybuf=0x7fffffffd590, prompt=XIL(0), dont_downcase_last=false, 
can_return_switch_frame=true, fix_current_buffer=true, prevent_redisplay=false) 
at keyboard.c:9957
#24 0x0000555555765a92 in command_loop_1 () at keyboard.c:1399
#25 0x0000555555859268 in internal_condition_case (bfun=0x5555557655db 
<command_loop_1>, handlers=XIL(0x90), hfun=0x5555557649a9 <cmd_error>) at 
eval.c:1478
#26 0x0000555555765194 in command_loop_2 (handlers=XIL(0x90)) at keyboard.c:1140
#27 0x000055555585834b in internal_catch (tag=XIL(0xf5d0), func=0x55555576516a 
<command_loop_2>, arg=XIL(0x90)) at eval.c:1208
#28 0x0000555555765126 in command_loop () at keyboard.c:1118
#29 0x000055555576444b in recursive_edit_1 () at keyboard.c:727
#30 0x0000555555764677 in Frecursive_edit () at keyboard.c:810
#31 0x000055555575f9dc in main (argc=6, argv=0x7fffffffda38) at emacs.c:2488

Lisp Backtrace:
"redisplay_internal (C function)" (0x0)
(gdb) 
quit
A debugging session is active.

        Inferior 1 [process 25227] will be killed.

Quit anyway? (y or n) y


Best,
Ihor