compiz crashed with SIGSEGV in sigc::signal_base::impl()

[Rocko]

Binary package hint: unity

I was using the desktop and it crashed. Unity/compiz had got confused about a gnome-terminal window and was making it act as if 'always-on-top' were set, and then it froze, so I ctrl-alt-f1'd to a tty session and then back, whereupon I got gdm-greeter, telling me I was logged in, so I logged into the active session and it crashed and threw me back to gdm-greeter.

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: unity 3.8.4-0ubuntu1
Uname: Linux 2.6.39-rc2-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
CheckboxSubmission: 1bd8e90541d49b96c13cbfcc9baf103b
CheckboxSystem: d00f84de8a555815fa1c4660280da308
CrashCounter: 1
Date: Mon Apr 11 12:09:05 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20100224.1)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=en_AU:en
 PATH=(custom, user)
 LANG=en_AU.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x7f6e704422f6 <_ZNK4sigc11signal_base4implEv+22>: mov 0x8(%rdi),%rbx
 PC (0x7f6e704422f6) ok
 source "0x8(%rdi)" (0x000000e8) not located in a known VMA region (needed readable region)!
 destination "%rbx" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 sigc::signal_base::impl() const () from /usr/lib/libsigc-2.0.so.0
 sigc::signal_base::connect(sigc::slot_base const&) () from /usr/lib/libsigc-2.0.so.0
 UnityScreen::UnityScreen(CompScreen*) () from /usr/lib/compiz/libunityshell.so
 CompPlugin::VTableForScreenAndWindow<UnityScreen, UnityWindow>::initScreen(CompScreen*) () from /usr/lib/compiz/libunityshell.so
 CompManager::initPlugin(CompPlugin*) ()
Title: compiz crashed with SIGSEGV in sigc::signal_base::impl()
UpgradeStatus: Upgraded to natty on 2011-04-08 (2 days ago)
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