unity-panel-service crashed with SIGSEGV in main_arena()

Bug Description

Up to date stack, respawning constantly

This is with accessibility set to on:
org.gnome.desktop.interface
tookit-accessibility

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: unity-services 4.4.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.0.0-7.8-generic 3.0.0
Uname: Linux 3.0.0-7-generic i686
NonfreeKernelModules: nvidia
Architecture: i386
CompizPlugins: [core,bailer,detection,composite,opengl,decor,mousepoll,vpswitch,regex,animation,snap,expo,move,compiztoolbox,place,grid,imgpng,gnomecompat,wall,ezoom,workarounds,staticswitcher,resize,fade,unitymtgrabhandles,scale,session,unitydialog,unityshell]
CrashCounter: 1
Date: Thu Jul 28 13:34:16 2011
ExecutablePath: /usr/lib/unity/unity-panel-service
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427)
ProcCmdline: /usr/lib/unity/unity-panel-service
ProcEnviron:
SHELL=/bin/bash
PATH=(custom, user)
LANG=fr_FR.UTF-8
SegvAnalysis:
Segfault happened at: 0xe513f2 <main_arena+50>: pop %ss
PC (0x00e513f2) in non-executable VMA region: 0x00e51000-0x00e54000 rw-p None
source "%ss" ok
destination "(%esp)" (0xbfa67bac) ok
SegvReason: executing writable VMA None
Signal: 11
SourcePackage: unity
StacktraceTop:
main_arena () from /lib/i386-linux-gnu/libc.so.6
?? () from /usr/lib/libgtk-3.so.0
g_cclosure_marshal_VOID__PARAM () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
g_closure_invoke () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
?? () from /usr/lib/i386-linux-gnu/libgobject-2.0.so.0
Title: unity-panel-service crashed with SIGSEGV in main_arena()
UpgradeStatus: Upgraded to oneiric on 2011年05月30日 (59 days ago)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare

StacktraceTop:
main_arena () from /lib/i386-linux-gnu/libc.so.6
notify_cb (obj=0x9e603f8, pspec=0x9dc3000) at /build/buildd/gtk+3.0-3.1.10/./gtk/a11y/gtkwidgetaccessible.c:65
g_cclosure_marshal_VOID__PARAM (closure=0x9e52938, return_value=0x0, n_param_values=2, param_values=0xb0c1bef0, invocation_hint=0xbfa67d00, marshal_data=0x0) at /build/buildd/glib2.0-2.29.14/./gobject/gmarshal.c:539
g_closure_invoke (closure=0x9e52938, return_value=0x0, n_param_values=2, param_values=0xb0c1bef0, invocation_hint=0xbfa67d00) at /build/buildd/glib2.0-2.29.14/./gobject/gclosure.c:773
signal_emit_unlocked_R (node=0x9db8cd0, detail=96, instance=0x9e603f8, emission_return=0x0, instance_and_params=0xb0c1bef0) at /build/buildd/glib2.0-2.29.14/./gobject/gsignal.c:3271

Sorry for the delay. In the end the solution was one line. panel_indicator_entry_accessible_ref_child is a implementation of atk_object_ref_child, and as the name implies, it supposes that a reference count is required.

The branch that I have just linked to this bug also add some NULL check conditions.

This bug was fixed in the package unity - 4.14.2-0ubuntu1

---------------
unity (4.14.2-0ubuntu1) oneiric; urgency=low

* New upstream release.
- unity crashed with AttributeError in reset_unity_compiz_profile(): 'str'
object has no attribute 'get_string' (LP: #809378)
- Trying to minimize Unity Dash to make it fit on a 1024x768 screen makes
Unity freeze and then, after I log out by killing X, never start again
(LP: #839200)
- unity-panel-service crashed with SIGSEGV in main_arena() (LP: #817477)
- UIFe: Panel - Indicators should be orderable regardless of their parent
IndicatorObject (LP: #823061)
- 'Show Desktop' fails to hand focus to desktop (LP: #836315)
- Dash - Functionality of top left close, minimise and maximise/restore
window decorations is confused (LP: #838875)
- unity-panel-service Leaks Memory (LP: #779185)
- Missing lens shortcuts (Super-A, Super-F) (LP: #834078)
- Unity window switcher takes over <alt> key (LP: #835699)
- update assets for window buttons (topleft) with dash opened
(LP: #836655)
- Where the average background colour is either very light or dark, adjust
this value to darken/lighten in order to preserve readability
(LP: #837993)
- Applications don't have priority over other results (LP: #839518)
- task tray icons are misaligned and badly sized (LP: #839354)
- UIFe: Dash - Shape and positioning of most of the elements in the Dash
need adjustment (LP: #841945)
- Cannot drag applications from dash to desktop (LP: #756614)
- systray icons still visible on each desktop in expo mode (LP: #759129)
- transparency on unity panel broken (LP: #827012)
- Window buttons and application menu don't autohide if left edge is
touched (LP: #835637)
- 'Filter results' should be right indented as in the mockups(and unity-
2d) (LP: #838118)
- window title should not appear until cursor leaves the menubar
(LP: #838759)
- Window title is not redrawn on leaving global-menu from buttons
(LP: #839488)
- In the dash, main text field can not be edited, except at the end
(LP: #840862)
- Quicklist can't be correctly hidden (LP: #843425)
- After double clicking on the panel to restore a window, the menus won't
be hidden on mouse-out (LP: #838021)
- After restoring a window the application title doesn't fade-out and it
goes below the menus (LP: #838479)
* debian/control:
- build-dep on latest libunity-dev for ABI/API break, nux
* debian/rules:
- bump shlibs, remove tweak for garantuing the version as the ABI
is considered stable until finale now.
-- Didier Roche <email address hidden> 2011年9月08日 20:07:50 +0200