Re: "corrupted size vs. prev_size"

[Lars Ingebrigtsen <larsi@gnus.org>]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> And I've now managed to catch a backtrace in gdb twice.  The error
> happens here both times:

But now I got a real segfault somewhere else:

#0  0x00005555557210e9 in sweep_conses () at alloc.c:7119
#1  0x0000555555727187 in gc_sweep () at alloc.c:7384
#2  garbage_collect () at alloc.c:6235
#3  0x0000555555727651 in maybe_garbage_collect () at alloc.c:6085
#4  0x0000555555748665 in maybe_gc ()
    at /home/larsi/src/emacs/trunk/src/lisp.h:5522
#5  Ffuncall (nargs=nargs@entry=2, args=args@entry=0x7fffffffd670)
    at eval.c:2868
#6  0x00005555556c3856 in call1 (arg1=0x555579d44a5d, fn=0xf0f0)
    at /home/larsi/src/emacs/trunk/src/lisp.h:3216
#7  timer_check_2 (idle_timers=<optimized out>, timers=<optimized out>)
    at keyboard.c:4591
#8  timer_check () at keyboard.c:4653
#9  0x00005555556c3b65 in readable_events (flags=flags@entry=1)
    at keyboard.c:3484
#10 0x00005555556c47a8 in get_input_pending (flags=flags@entry=1)
    at keyboard.c:7225
#11 0x00005555556cb584 in detect_input_pending_run_timers (do_display=false)
    at keyboard.c:10755
#12 read_char
    (commandflag=1, map=0x55557836f8c3, prev_event=0x0, used_mouse_menu=0x7fffffffdb8b, end_time=0x0) at keyboard.c:2581
#13 0x00005555556cd899 in read_key_sequence

So it's just random out-of-bounds writing.  (In gif_load somewhere,
apparently -- I'm able to trigger the problem with a gif-only test.)

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no