Re: SIGSEGV reading email in Gnus - GIF support problem?

[Eli Zaretskii]

> From: Charles Sebold <sebold@lcms.org>
> Date: Wed, 05 Dec 2001 10:25:52 -0600
> 
> 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)

Can you try building with a different version of libungif?  I use
4.1.0b1, with no visible problems.

> (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

A crash in `free', eh?  That might mean some code corrupts the malloc
data structures, in which case the offending code could be anywhere.

Can you reproduce the crash at will, by just displaying that specific
GIF image?  If so, does it happen with "emacs -q --no-site-file", if
you, e.g., turn on the auto-image-file-mode and then visit that GIF
file with C-x C-f?