firefox 11 SIGSEGV on startup when ocra/accessibility are enabled

[Xerxes Rånby]

Testcase:
enable the ocra screenreader in ubuntu system settings under accessibility
firefox now crash on startup with a segmentation fault casued by firefox and libatk-1.0.so.0 interaction.

quit ocra and disable the screen reader
firefox can now start normally again

Tested using Ubuntu 12.04 precise using
firefox_11.0~b5+build1-0ubuntu1_i386.deb
and
libatk1.0-0_2.3.91-0ubuntu1_i386.deb

Backtrace:
xranby@xranby-ESPRIMO-P7935:~$ firefox -g
GNU gdb (Ubuntu/Linaro 7.4-0ubuntu1) 7.4
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "i686-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/lib/firefox-11.0/firefox...Reading symbols from /usr/lib/debug/usr/lib/firefox-11.0/firefox...done.
done.
(gdb) run
Starting program: /usr/lib/firefox-11.0/firefox
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
[New Thread 0xb77ffb40 (LWP 18856)]
...
[New Thread 0xa70fdb40 (LWP 18876)]

Program received signal SIGSEGV, Segmentation fault.
0x00c25d82 in nsAttrAndChildArray::IndexOfAttr (this=0xab5b3f4c, aLocalName=0xb3731040, aNamespaceID=0)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/base/src/nsAttrAndChildArray.cpp:534
534 /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/base/src/nsAttrAndChildArray.cpp: Filen eller katalogen finns inte.
(gdb) bt
#0 0x00c25d82 in nsAttrAndChildArray::IndexOfAttr (this=0xab5b3f4c, aLocalName=0xb3731040, aNamespaceID=0)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/base/src/nsAttrAndChildArray.cpp:534
#1 0x00c72331 in nsGenericElement::GetAttrInfo (this=0xab5b3f10, aNamespaceID=0, aName=0xb3731040)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/base/src/nsGenericElement.cpp:4697
#2 0x00fa154a in nsXULElement::GetAttrInfo (this=0xab5b3f10, aNamespaceID=0, aName=0xb3731040)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/xul/content/src/nsXULElement.cpp:2229
#3 0x00fa15b5 in nsXULElement::FindLocalOrProtoAttr (this=0xab5b3f10, aNameSpaceID=0, aName=0xb3731040)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/xul/content/src/nsXULElement.h:625
#4 0x00fa17ac in nsXULElement::GetAttr (this=0xab5b3f10, aNameSpaceID=0, aName=0xb3731040, aResult=...)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/xul/content/src/nsXULElement.cpp:1221
#5 0x00c57735 in nsDocument::GetTitle (this=0xac0c7000, aTitle=...)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/content/base/src/nsDocument.cpp:5200
#6 0x0130169d in GetName (aName=..., this=0xa81ca500)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/accessible/src/base/nsRootAccessible.cpp:142
#7 nsRootAccessible::GetName (this=0xa81ca500, aName=...)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/accessible/src/base/nsRootAccessible.cpp:126
#8 0x01317698 in getNameCB (aAtkObj=0xa8fdd7f0)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/accessible/src/atk/nsAccessibleWrap.cpp:710
#9 0x02c3d8d6 in atk_object_get_name () from /usr/lib/i386-linux-gnu/libatk-1.0.so.0
#10 0x02c3e483 in atk_object_set_name () from /usr/lib/i386-linux-gnu/libatk-1.0.so.0
#11 0x013176f5 in getNameCB (aAtkObj=0xa8fdd7f0)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/accessible/src/atk/nsAccessibleWrap.cpp:716
#12 0x02c3d8d6 in atk_object_get_name () from /usr/lib/i386-linux-gnu/libatk-1.0.so.0
#13 0x02c3e483 in atk_object_set_name () from /usr/lib/i386-linux-gnu/libatk-1.0.so.0
#14 0x013176f5 in getNameCB (aAtkObj=0xa8fdd7f0)
    at /build/buildd/firefox-11.0~b5+build1/build-tree/mozilla/accessible/src/atk/nsAccessibleWrap.cpp:716
#15 0x02c3d8d6 in atk_object_get_name () from /usr/lib/i386-linux-gnu/libatk-1.0.so.0
#16 0x02c3e483 in atk_object_set_name () from /usr/lib/i386-linux-gnu/libatk-1.0.so.0
...

[Xerxes Rånby (xranby)]

After upgrading my system to libatk1.0-0 2.3.91-0ubuntu2 firefox starts fine while ocra are running.