Reproducible crashes: dropping an URL (was: SEGV in x_catch_errors_unwind (x86_64-unknown-linux-gnu))

[Reiner Steib]

On Fri, Feb 17 2006, Reiner Steib wrote:

> I updated and recompiled with ENABLE_CHECKING some days ago.  Now I
> got another crash:
[...]
> If I can provide more information, please tell me which gdb commands I
> should use.

I found out a recipe to reproduce the crash with a current trunk build
on both, x86_64 and i586:

- Start with `-Q'

- Open www.gnu.org in Firefox.

- Drag/drop any URL into Emacs' scratch buffer, e.g. "GNU Project".

=> crash.  (My 2006-01-27 built doesn't crash here.)

Nick, does this recipe crash your Emacs too?

Often `bt full' and `xbacktrace' didn't provide much output, if any.
Here is a gdb session on x86_64 with a quite verbose backtrace:

--8<---------------cut here---------------start------------->8---
GNU gdb 6.2.1
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "x86_64-suse-linux"...Using host libthread_db 
library "/lib64/tls/libthread_db.so.1".

DISPLAY = :0.0
TERM = screen
Breakpoint 1 at 0x52f910: file [...]/emacs/src/emacs.c, line 463.
Breakpoint 2 at 0x558db0: file [...]/emacs/src/sysdep.c, line 1373.
(gdb) r -Q
Starting program: [...]/x86_64/src/emacs -Q
[Thread debugging using libthread_db enabled]
[New Thread 182940272320 (LWP 29178)]
[Switching to Thread 182940272320 (LWP 29178)]
Breakpoint 3 at 0x4fc280: file [...]/emacs/src/xterm.c, line 7814.

Emacs fatal error: [...]/emacs/src/alloc.c:3212: assertion failed: 
!handling_signal

Breakpoint 1, abort ()
    at [...]/emacs/src/emacs.c:463
463     {
(gdb) bt
#0  abort () at [...]/emacs/src/emacs.c:463
#1  0x00000000005a2304 in die (msg=Variable "msg" is not available.
)
    at [...]/emacs/src/alloc.c:6193
#2  0x00000000005a6334 in Fmake_symbol (name=16370227)
    at [...]/emacs/src/alloc.c:3236
#3  0x00000000005e6764 in Fintern (string=16370227, obarray=10809332)
    at [...]/emacs/src/lread.c:3218
#4  0x0000000000510cfb in x_atom_to_symbol (dpy=0xf63e40, atom=Variable "atom" 
is not available.
)
    at [...]/emacs/src/xselect.c:383
#5  0x00000000005113de in x_handle_dnd_message (f=0x10119c0, 
    event=0x7fbfffadc0, dpyinfo=Variable "dpyinfo" is not available.
)
    at [...]/emacs/src/xselect.c:2718
#6  0x0000000000500dfe in handle_one_xevent (dpyinfo=0xf99b10, 
    eventp=0x7fbfffb430, finish=0x9e67d4, hold_quit=0x7fbfffc7b0)
    at [...]/emacs/src/xterm.c:5846
#7  0x0000000000502fbc in event_handler_gdk (gxev=Variable "gxev" is not 
available.
)
    at [...]/emacs/src/xterm.c:5627
#8  0x0000002a95aa02b5 in gdk_event_apply_filters ()
   from /opt/gnome/lib64/libgdk-x11-2.0.so.0
#9  0x0000002a95aa1bf8 in gdk_event_translate ()
   from /opt/gnome/lib64/libgdk-x11-2.0.so.0
#10 0x0000002a95aa3041 in _gdk_events_queue ()
   from /opt/gnome/lib64/libgdk-x11-2.0.so.0
#11 0x0000002a95aa33fc in gdk_event_dispatch ()
   from /opt/gnome/lib64/libgdk-x11-2.0.so.0
#12 0x0000002a96623025 in g_main_context_dispatch ()
   from /opt/gnome/lib64/libglib-2.0.so.0
#13 0x0000002a96625669 in g_main_context_iterate ()
   from /opt/gnome/lib64/libglib-2.0.so.0
#14 0x0000002a96625763 in g_main_context_iteration ()
   from /opt/gnome/lib64/libglib-2.0.so.0
#15 0x0000002a9577e66f in gtk_main_iteration ()
   from /opt/gnome/lib64/libgtk-x11-2.0.so.0
#16 0x00000000004fc0ff in XTread_socket (sd=Variable "sd" is not available.
)
    at [...]/emacs/src/xterm.c:7057
#17 0x000000000053abc6 in read_avail_input (expected=1)
    at [...]/emacs/src/keyboard.c:6720
#18 0x000000000053ad6a in handle_async_input ()
    at [...]/emacs/src/keyboard.c:6863
#19 0x000000000053ae22 in input_available_signal (signo=29)
    at [...]/emacs/src/keyboard.c:6905
#20 <signal handler called>
#21 0x0000002a974a42a5 in __select_nocancel () from /lib64/tls/libc.so.6
#22 0x000000000060b1fe in wait_reading_process_output (time_limit=0, 
    microsecs=0, read_kbd=-1, do_display=1, wait_for_cell=10808305, 
    wait_proc=0x0, just_wait_proc=0)
    at [...]/emacs/src/process.c:4490
#23 0x0000000000542bd6 in read_char (commandflag=1, nmaps=2, 
    maps=0x7fbfffd4e0, prev_event=10808305, used_mouse_menu=0x7fbfffd554)
    at [...]/emacs/src/keyboard.c:3940
#24 0x0000000000546e3b in read_key_sequence (keybuf=0x7fbfffd6f0, bufsize=30, 
    prompt=10808305, dont_downcase_last=0, can_return_switch_frame=1, 
    fix_current_buffer=1)
    at [...]/emacs/src/keyboard.c:8874
#25 0x000000000054a672 in command_loop_1 ()
    at [...]/emacs/src/keyboard.c:1536
#26 0x00000000005c3581 in internal_condition_case (
    bfun=0x54a3b0 <command_loop_1>, handlers=10901729, 
    hfun=0x540ed0 <cmd_error>)
    at [...]/emacs/src/eval.c:1465
#27 0x000000000053fcfa in command_loop_2 ()
    at [...]/emacs/src/keyboard.c:1328
#28 0x00000000005c36d0 in internal_catch (tag=Variable "tag" is not available.
)
    at [...]/emacs/src/eval.c:1211
#29 0x00000000005408f8 in command_loop ()
    at [...]/emacs/src/keyboard.c:1307
#30 0x0000000000540991 in recursive_edit_1 ()
    at [...]/emacs/src/keyboard.c:1000
#31 0x0000000000540b30 in Frecursive_edit ()
    at [...]/emacs/src/keyboard.c:1061
#32 0x0000000000530756 in main (argc=2, argv=0x7fbfffdf78)
    at [...]/emacs/src/emacs.c:1789
(gdb) xbacktrace 
(gdb) 
(gdb) p x_error_message
$1 = (struct x_error_message_stack *) 0x0
--8<---------------cut here---------------end--------------->8---

Here's is a gdb session on i586:

--8<---------------cut here---------------start------------->8---
GNU gdb 6.2.1
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i586-suse-linux"...Using host libthread_db library 
"/lib/tls/libthread_db.so.1".

DISPLAY = localhost:13.0
TERM = screen
Breakpoint 1 at 0x81612a6: file [...]/emacs/src/emacs.c, line 464.
Breakpoint 2 at 0x8187b19: file [...]/emacs/src/sysdep.c, line 1393.
(gdb) r -Q
Starting program: [...]/i686/src/emacs -Q
[Thread debugging using libthread_db enabled]
[New Thread 1083362592 (LWP 28407)]
[Switching to Thread 1083362592 (LWP 28407)]
Breakpoint 3 at 0x812fdfc: file [...]/emacs/src/xterm.c, line 7820.

Emacs fatal error: [...]/emacs/src/alloc.c:3212: assertion failed: 
!handling_signal

Breakpoint 1, abort ()
    at [...]/emacs/src/emacs.c:464
464       kill (getpid (), SIGABRT);
(gdb) bt full
#0  abort () at [...]/emacs/src/emacs.c:464
No locals.
#1  0x081cdb1b in die (msg=0x82a9e00 "assertion failed: !handling_signal", 
    file=0x82a9614 "[...]/emacs/src/alloc.c", line=3212) at 
[...]/emacs/src/alloc.c:6193
No locals.
#2  0x081d15d5 in Fmake_symbol (name=146264523)
    at [...]/emacs/src/alloc.c:3236
        val = Variable "val" is not available.
(gdb) xbacktrace 
(gdb) p x_error_message
$1 = (struct x_error_message_stack *) 0x0
(gdb) 
--8<---------------cut here---------------end--------------->8---

Bye, Reiner.
-- 
       ,,,
      (o o)
---ooO-(_)-Ooo---  |  PGP key available  |  http://rsteib.home.pages.de/