compiz crashed with SIGSEGV in __memcpy_ssse3_back()

I have no idea why this happened, I just upgraded and restarted.

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: libnux-0.9-0 0.9.34-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.38-7.37-generic 2.6.38
Uname: Linux 2.6.38-7-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
CrashCounter: 1
Date: Tue Mar 22 11:02:59 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Beta amd64 (20100901.1)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=en_US:en
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x7f9348a4c1db <__memcpy_ssse3_back+6827>: movdqu -0x40(%rsi),%xmm4
 PC (0x7f9348a4c1db) ok
 source "-0x40(%rsi)" (0x009e0ff0) not located in a known VMA region (needed readable region)!
 destination "%xmm4" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: nux
StacktraceTop:
 __memcpy_ssse3_back () at ../sysdeps/x86_64/multiarch/memcpy-ssse3-back.S:1625
 nux::CairoGraphics::GetBitmap() () from /usr/lib/libnux-image-0.9.so.0
 PanelMenuView::Refresh() () from /usr/lib/compiz/libunityshell.so
 PanelMenuView::OnActiveWindowChanged(_BamfView*, _BamfView*) () from /usr/lib/compiz/libunityshell.so
 g_closure_invoke (closure=0x150b800, return_value=0x0, n_param_values=3, param_values=0xa2ade0, invocation_hint=0x7fff4b97dd30) at /build/buildd/glib2.0-2.28.4/./gobject/gclosure.c:767
Title: compiz crashed with SIGSEGV in __memcpy_ssse3_back()
UpgradeStatus: Upgraded to natty on 2011-02-17 (32 days ago)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
XsessionErrors: (nautilus:1579): GConf-CRITICAL **: gconf_value_free: assertion `value != NULL' failed