(gdb) bt
#0  0x00007ffff31b0ba5 in raise () from /lib/libc.so.6
#1  0x00007ffff31b46b0 in abort () from /lib/libc.so.6
#2  0x00007ffff31a9a71 in __assert_fail () from /lib/libc.so.6
#3  0x000000000042cdd5 in content_open (h=<value optimised out>, bw=0xb97810,
    page=0xcc8070, index=0, box=0xd9fe60, params=0x0) at content/content.c:1126
#4  0x000000000048f236 in html_open (c=0xcc8070, bw=0xb97810,
    page=<value optimised out>, index=<value optimised out>, box=<value optimised out>,
    params=<value optimised out>) at render/html.c:1883
#5  0x0000000000446c1b in browser_window_callback (c=0xc67960,
    event=<value optimised out>, pw=<value optimised out>) at desktop/browser.c:549
#6  0x0000000000434859 in hlcache_content_callback (c=<value optimised out>,
    msg=<value optimised out>, data=..., pw=0x6a7f) at content/hlcache.c:694
#7  0x000000000042c76b in content_broadcast (c=0xcc8070, msg=CONTENT_MSG_READY, data=...)
    at content/content.c:1102
#8  0x000000000042dcbc in content_set_ready (c=0xcc8070) at content/content.c:712
#9  0x000000000049081d in html_finish_conversion (c=0xcc8070) at render/html.c:559
#10 0x000000000043d865 in nscss_register_imports (c=0xce1240) at css/css.c:570
#11 0x000000000043d925 in nscss_import_complete (ctx=0xd43600) at css/css.c:518
#12 0x000000000043df90 in nscss_import (handle=<value optimised out>, event=0x6a7f,
    pw=0x6) at css/css.c:493
#13 0x0000000000434859 in hlcache_content_callback (c=<value optimised out>,
    msg=<value optimised out>, data=..., pw=0x6a7f) at content/hlcache.c:694
#14 0x000000000042c76b in content_broadcast (c=0x903a30, msg=CONTENT_MSG_DONE, data=...)
    at content/content.c:1102
#15 0x000000000042dc40 in content_set_done (c=0x903a30) at content/content.c:726
#16 0x000000000043d5ec in nscss_content_done (css=0x903a68, pw=<value optimised out>)
    at css/css.c:377
#17 0x000000000043d9da in nscss_convert_css_data (c=0x903a68) at css/css.c:237
#18 0x000000000043daa1 in nscss_convert (c=0x903a30) at css/css.c:203
---Type <return> to continue, or q <return> to quit---
#19 0x000000000042df9a in content_convert (llcache=<value optimised out>,
    event=<value optimised out>, pw=<value optimised out>) at content/content.c:686
#20 content_llcache_callback (llcache=<value optimised out>,
    event=<value optimised out>, pw=<value optimised out>) at content/content.c:572
#21 0x0000000000435a8c in llcache_object_notify_users (object=0xd50940)
    at content/llcache.c:1517
#22 0x0000000000435eb8 in llcache_poll () at content/llcache.c:317
#23 0x0000000000434fb6 in hlcache_poll () at content/hlcache.c:161
#24 0x000000000044e061 in netsurf_main_loop () at desktop/netsurf.c:170
#25 0x0000000000468c84 in main (argc=1, argv=0x7fffffffe778) at gtk/gui.c:495
(gdb)