unity-2d-shell crashed with SIGSEGV in QMetaObject::changeGuard()

[Luis Henriques]

Just got an error message stating unity-2d-shell crashed. This happen when I lost connection to Mumble server and closed the application. Also, the following was logged on kernel:

[18223.600264] unity-2d-shell[2087]: segfault at 38 ip 00007f81b7ab1ee9 sp 00007fff9d272e60 error 4 in libQtCore.so.4.8.0[7f81b7921000+2c5000]

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: unity-2d-shell 5.8.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-20.32-generic 3.2.12
Uname: Linux 3.2.0-20-generic x86_64
ApportVersion: 1.95-0ubuntu1
Architecture: amd64
Date: Tue Mar 27 14:07:46 2012
ExecutablePath: /usr/bin/unity-2d-shell
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111011)
ProcCmdline: unity-2d-shell
ProcEnviron:
 LANGUAGE=en_GB:en
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: unity-2d
Title: unity-2d-shell crashed with SIGSEGV in QMetaObject::changeGuard()
UpgradeStatus: Upgraded to precise on 2012-02-28 (27 days ago)
UserGroups: adm admin cdrom dialout kvm lpadmin plugdev sambashare

[Apport retracing service (apport)]

StacktraceTop:
 QMetaObject::changeGuard (ptr=0x3474090, o=0x2971790) at kernel/qobject.cpp:461
 operator= (p=0x2971790, this=0x3474090) at /usr/include/qt4/QtCore/qpointer.h:68
 Application::setBamfApplication (this=0x3474070, application=0x2971790) at /build/buildd/unity-2d-5.8.0/libunity-2d-private/src/application.cpp:428
 ApplicationsList::insertBamfApplication (this=0x1cbaa40, bamf_application=0x2971790) at /build/buildd/unity-2d-5.8.0/libunity-2d-private/src/applicationslist.cpp:259
 QMetaObject::activate (sender=0x61cb90, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fff9d273090) at kernel/qobject.cpp:3547

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.