SIGSEGV reading email in Gnus - GIF support problem?

[Charles Sebold]

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In GNU Emacs 21.1.1 (i686-pc-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2001-10-24 on sebold
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: 
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: C
  locale-coding-system: nil
  default-enable-multibyte-characters: t

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

Displaying a certain GIF in Emacs 21.1 causes it to SIGSEGV.  I
discovered this when it was mailed to me by somebody and I tried to view
it in Gnus.  I am running Debian unstable, up-to-date as of this
morning.

The following are the versions of GIF libraries that I have on this
system, according to Debian's package management.  I compiled this
binary of Emacs myself with no patches.

ii  giflib3g       3.0-6          shared library for GIF images (runtime lib)
ii  libungif4-dev  4.1-9          shared library for GIF images (development f
ii  libungif4g     4.1-9          shared library for GIF images (runtime lib)


Here's the backtrace from GDB:

Program received signal SIGSEGV, Segmentation fault.
0x40361a5b in free () from /lib/libc.so.6
(gdb) bt
#0  0x40361a5b in free () from /lib/libc.so.6
#1  0x0810f1ba in emacs_blocked_free (ptr=0x10) at alloc.c:688
#2  0x40361a49 in free () from /lib/libc.so.6
#3  0x401c2956 in FreeMapObject () from /usr/lib/libungif.so.4
#4  0x401c2e98 in FreeSavedImages () from /usr/lib/libungif.so.4
#5  0x401c084b in DGifCloseFile () from /usr/lib/libungif.so.4
#6  0x080c4b88 in gif_load (f=0x844ae38, img=0x8a0ab10) at xfns.c:9899
#7  0x080bffea in lookup_image (f=0x844ae38, spec=1483533092) at xfns.c:6099
#8  0x0805ec79 in handle_single_display_prop (it=0xbfffe734, prop=1483533092, 
    object=1217783288, position=0xbfffe7b8, display_replaced_before_p=0)
    at xdisp.c:3044
#9  0x0805e3f4 in handle_display_prop (it=0xbfffe734) at xdisp.c:2758
#10 0x0805d491 in handle_stop (it=0xbfffe734) at xdisp.c:2002
#11 0x080602cd in reseat (it=0xbfffe734, pos={charpos = 1, bytepos = 1}, 
    force_p=1) at xdisp.c:4008
#12 0x0805cf4f in init_iterator (it=0xbfffe734, w=0x844af60, charpos=1, 
    bytepos=1, row=0x84f70b0, base_face_id=DEFAULT_FACE_ID) at xdisp.c:1691
#13 0x0805cfea in start_display (it=0xbfffe734, w=0x844af60, pos=
      {charpos = 1, bytepos = 1}) at xdisp.c:1710
#14 0x08069d34 in try_window (window=1212460896, pos=
      {charpos = 1, bytepos = 1}) at xdisp.c:10557
#15 0x080691e2 in redisplay_window (window=1212460896, just_this_one_p=0)
    at xdisp.c:10230
#16 0x08066f11 in redisplay_windows (window=1212460896) at xdisp.c:9182
#17 0x08066f04 in redisplay_windows (window=1217706600) at xdisp.c:9180
#18 0x080666bb in redisplay_internal (preserve_echo_area=1) at xdisp.c:8786
#19 0x08066b3a in redisplay_preserve_echo_area (from_where=2) at xdisp.c:9006
#20 0x08056c92 in sit_for (sec=0, usec=100000, reading=0, display=1, 
    initial_display=1) at dispnew.c:6233
#21 0x080d19d5 in command_loop_1 () at keyboard.c:1669
#22 0x08121ea9 in internal_condition_case (bfun=0x80d0dd0 <command_loop_1>, 
    handlers=405283356, hfun=0x80d0a14 <cmd_error>) at eval.c:1267
#23 0x080d0ca8 in command_loop_2 () at keyboard.c:1245
#24 0x08121a3d in internal_catch (tag=405244964, 
    func=0x80d0c84 <command_loop_2>, arg=405187036) at eval.c:1030
#25 0x080d0c57 in command_loop () at keyboard.c:1224
#26 0x080d07d1 in recursive_edit_1 () at keyboard.c:950
#27 0x080d0900 in Frecursive_edit () at keyboard.c:1006
#28 0x080cf86f in main (argc=1, argv=0xbffff724, envp=0xbffff72c)
    at emacs.c:1547
#29 0x4030c65f in __libc_start_main () from /lib/libc.so.6

I have the GIF itself uploaded to my homepage if you are interested in
trying it on your own.

http://www.livingtorah.org/~csebold/breaksemacs.gif

If you want more information I would be happy to supply it.  Sorry I
know nothing about GDB or I would try to supply more now.

Recent input:
<help-echo> C-x 1 <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
C-h d C-g C-h C-h SPC SPC SPC ESC C-x C-f / u s <tab> 
l o c <tab> s h <tab> e m <tab> 2 1 <tab> e t <tab> 
D <tab> E <tab> <return> C-v C-v C-v C-v C-v C-v C-v 
C-v M-x e m <tab> <backspace> <backspace> C-g <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <menu-bar> 
<help-menu> <report-emacs-bug>

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-- 
Charles Sebold                                      20th of Kislev, 5762
LCMS - Office of Information Systems                http://unix.ois.org/
        *** Opinions expressed herein are not necessarily ***
        *** those of the Lutheran Church - Missouri Synod ***