pidgin crashes in g_list_last on new incoming conversation

[Max Kaehn]

Sometimes, when a new conversation starts, pidgin will crash with a segmentation fault. Most recently observed in pidgin 1:2.10.7-0ubuntu4.1 on 13.04 64-bit:

Core was generated by `/usr/bin/pidgin'.
Program terminated with signal 11, Segmentation fault.
#0 0x00007f09b01a6633 in g_list_last ()
   from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1 0x00007f09b01a66ce in g_list_append ()
   from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007f09b2e4d2c3 in pidgin_conv_window_add_gtkconv (win=0x7f09b3bb82f0,
    gtkconv=gtkconv@entry=0x7f09b4af0800)
    at /build/buildd/pidgin-2.10.7/./pidgin/gtkconv.c:9468
#3 0x00007f09b2e51482 in private_gtkconv_new (conv=0x7f09b4a79c50, hidden=1)
    at /build/buildd/pidgin-2.10.7/./pidgin/gtkconv.c:5448
#4 0x00007f09afe8d02d in purple_conversation_new (
    type=type@entry=PURPLE_CONV_TYPE_IM, account=account@entry=0x7f09b393efa0,
    name=name@entry=0x7f09b4ed3e20 "<email address hidden>/windows-24012") at /build/buildd/pidgin-2.10.7/./libpurple/conversation.c:450
#5 0x00007f09b2e521be in received_im_msg_cb (account=0x7f09b393efa0,
    sender=0x7f09b4ed3e20 "<email address hidden>/windows-24012",
    message=<optimized out>, conv=0x0, flags=<optimized out>)
    at /build/buildd/pidgin-2.10.7/./pidgin/gtkconv.c:5503
#6 0x00007f09afebf532 in purple_signal_emit_vargs (instance=<optimized out>,
    signal=signal@entry=0x7f09aff0ce89 "received-im-msg",
    args=args@entry=0x7fffb5fba628)
    at /build/buildd/pidgin-2.10.7/./libpurple/signals.c:482
#7 0x00007f09afebf681 in purple_signal_emit (instance=<optimized out>,
    signal=signal@entry=0x7f09aff0ce89 "received-im-msg")
    at /build/buildd/pidgin-2.10.7/./libpurple/signals.c:434
#8 0x00007f09afebdeec in serv_got_im (gc=gc@entry=0x7f09b40326a0,
    who=<optimized out>, msg=<optimized out>, flags=PURPLE_MESSAGE_RECV,
    flags@entry=(unknown: 0), mtime=1368818098)
    at /build/buildd/pidgin-2.10.7/./libpurple/server.c:608
#9 0x00007f0992ba1988 in handle_chat (jm=0x7f09b5046820)
    at /build/buildd/pidgin-2.10.7/./libpurple/protocols/jabber/message.c:159
#10 jabber_message_parse (js=js@entry=0x7f09b4fe7280, packet=<optimized out>)
    at /build/buildd/pidgin-2.10.7/./libpurple/protocols/jabber/message.c:786
#11 0x00007f0992b96a7b in jabber_process_packet (js=js@entry=0x7f09b4fe7280,
    packet=packet@entry=0x7fffb5fba9b8)
    at /build/buildd/pidgin-2.10.7/./libpurple/protocols/jabber/jabber.c:349
#12 0x00007f0992ba3727 in jabber_parser_element_end_libxml (
    user_data=0x7f09b4fe7280, element_name=<optimized out>,
    prefix=<optimized out>, namespace=<optimized out>)
    at /build/buildd/pidgin-2.10.7/./libpurple/protocols/jabber/parser.c:169
#13 0x00007f09aee1a493 in ?? () from /usr/lib/x86_64-linux-gnu/libxml2.so.2
#14 0x00007f09aee2150e in ?? () from /usr/lib/x86_64-linux-gnu/libxml2.so.2
#15 0x00007f09aee22e0e in xmlParseChunk ()
   from /usr/lib/x86_64-linux-gnu/libxml2.so.2
#16 0x00007f0992ba3bcd in jabber_parser_process (js=0x7f09b4fe7280,
    buf=<optimized out>, len=<optimized out>)
    at /build/buildd/pidgin-2.10.7/./libpurple/protocols/jabber/parser.c:279
#17 0x00007f0992b92736 in jabber_recv_cb_ssl (data=0x7f09b40326a0,
    gsc=0x7f09b49da840, cond=<optimized out>)
    at /build/buildd/pidgin-2.10.7/./libpurple/protocols/jabber/jabber.c:659
#18 0x00007f09b2e5986d in pidgin_io_invoke (source=<optimized out>,
    condition=<optimized out>, data=0x7f09b5299e10)
    at /build/buildd/pidgin-2.10.7/./pidgin/gtkeventloop.c:73
#19 0x00007f09b01a9f05 in g_main_context_dispatch ()
   from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007f09b01aa248 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007f09b01aa6ba in g_main_loop_run ()
   from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#22 0x00007f09b1422fe7 in gtk_main ()
   from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#23 0x00007f09b2e1e3bc in main (argc=1, argv=0x7fffb5fbd208)
    at /build/buildd/pidgin-2.10.7/./pidgin/gtkmain.c:881