bug#33222: Crash when visiting an org file from within Dired.

[Robert Pluim <rpluim@gmail.com>]

Robert Pluim <rpluim@gmail.com> writes:

> vordoo <vordoo@yahoo.com> writes:
>
>> On 11/1/18 6:05 AM, Eli Zaretskii wrote:
>>> A wild guess: this is bug#30045 again.
>>> Can you try the latest emacs-26 branch of the Emacs repository?
>>
>> Thanks & yes. This bug still stands on GNU Emacs 26.1.50 (build 1,
>> x86_64-pc-linux-gnu, GTK+ Version 3.24.1) of 2018-11-01.
>
> It doesnʼt crash for me. Can you get a backtrace from gdb of the
> crash?

Actually it does crash, you just have to make sure that you haven't
already visited the relevant org file before you change org-mode-hook.

Thread 1 "emacs" received signal SIGSEGV, Segmentation fault.
face_at_buffer_position (w=0x1409c30 <bss_sbrk_buffer+8361648>, pos=<optimized out>, endptr=endptr@entry=0x7fffffff7fe0, limit=<optimized out>, mouse=mouse@entry=false, base_face_id=<optimized out>)
    at xfaces.c:5964
5964	  memcpy (attrs, default_face->lface, sizeof attrs);
(gdb) bt
#0  0x00000000004c2cf4 in face_at_buffer_position (w=0x1409c30 <bss_sbrk_buffer+8361648>, pos=<optimized out>, endptr=endptr@entry=0x7fffffff7fe0, limit=<optimized out>, mouse=mouse@entry=false, base_face_id=<optimized out>) at xfaces.c:5964
#1  0x0000000000447cf1 in handle_face_prop (it=0x7fffffff8090) at xdisp.c:3965
#2  0x00000000004422ea in handle_stop (it=0x7fffffff8090) at xdisp.c:3473
#3  0x0000000000444217 in start_display (it=it@entry=0x7fffffff8090, w=w@entry=0x1409c30 <bss_sbrk_buffer+8361648>, pos=...) at xdisp.c:3104
#4  0x0000000000454deb in try_window (window=..., window@entry=XIL(0x1409c35), pos=..., flags=flags@entry=1) at xdisp.c:17717
#5  0x00000000004684bc in redisplay_window (window=XIL(0x1409c35), just_this_one_p=just_this_one_p@entry=false) at xdisp.c:17170
#6  0x000000000046af4b in redisplay_window_0 (window=..., window@entry=XIL(0x1409c35)) at xdisp.c:14926
#7  0x000000000056d656 in internal_condition_case_1 (bfun=bfun@entry=0x46af20 <redisplay_window_0>, arg=..., arg@entry=XIL(0x1409c35), handlers=..., hfun=hfun@entry=0x42ff40 <redisplay_window_error>)
    at eval.c:1360
#8  0x0000000000434045 in redisplay_windows (window=XIL(0x1409c35)) at xdisp.c:14906
#9  0x000000000045887d in redisplay_internal () at xdisp.c:14395
#10 0x000000000045a585 in redisplay () at xdisp.c:13613
#11 0x000000000050207b in read_char (commandflag=commandflag@entry=1, map=..., 
    map@entry=XIL(0x39424b3), prev_event=..., used_mouse_menu=used_mouse_menu@entry=0x7fffffffd61b, end_time=end_time@entry=0x0) at keyboard.c:2480
#12 0x0000000000504f8c in read_key_sequence (keybuf=keybuf@entry=0x7fffffffd720, prompt=XIL(0x7fffffffd718), 
    prompt@entry=XIL(0), dont_downcase_last=dont_downcase_last@entry=false, can_return_switch_frame=can_return_switch_frame@entry=true, fix_current_buffer=fix_current_buffer@entry=true, prevent_redisplay=prevent_redisplay@entry=false, bufsize=30) at keyboard.c:9148
#13 0x0000000000506a5e in command_loop_1 () at keyboard.c:1368
#14 0x000000000056d5be in internal_condition_case (bfun=bfun@entry=0x506820 <command_loop_1>, handlers=..., handlers@entry=XIL(0x52e0), hfun=hfun@entry=0x4fcee0 <cmd_error>) at eval.c:1336
#15 0x00000000004f8034 in command_loop_2 (ignore=..., ignore@entry=XIL(0)) at keyboard.c:1110
#16 0x000000000056d52d in internal_catch (tag=..., tag@entry=XIL(0xc7e0), func=func@entry=0x4f8010 <command_loop_2>, arg=..., arg@entry=XIL(0)) at eval.c:1101
#17 0x00000000004f7fcb in command_loop () at keyboard.c:1089
#18 0x00000000004fcaf3 in recursive_edit_1 () at keyboard.c:695
#19 0x00000000004fce16 in Frecursive_edit () at keyboard.c:766
#20 0x000000000041a9ce in main (argc=2, argv=0x7fffffffdac8) at emacs.c:1717

Lisp Backtrace:
"redisplay_internal (C function)" (0x0)
(gdb) p attrs
$1 = {make_number(1), XIL(0x55883af632f3f300), XIL(0x6150), make_number(1510779), XIL(0x7), XIL(0x7fffffff7f60), XIL(0x7fffffff7f58), XIL(0x39b6300), XIL(0), XIL(0x2eaae00), make_number(1), 
  XIL(0x7fffffff7dd0), XIL(0x28), XIL(0x55883af632f3f300), XIL(0), XIL(0x7fffffff8090), XIL(0), XIL(0x1), XIL(0x1)}
(gdb) p default_face
$2 = (struct face *) 0x0

I have no idea how default_face can be NULL here.

Robert