compiz crashed with SIGSEGV in g_main_context_dispatch()

I was moving the mouse fast and then directly (immediately) went to type in the Ubuntu search box, and the GUI froze for a minute or so.

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: unity 5.18.0-0ubuntu2
ProcVersionSignature: Ubuntu 3.2.0-48.74-generic 3.2.46
Uname: Linux 3.2.0-48-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu17.3
Architecture: amd64
CrashCounter: 1
Date: Sun Jun 16 15:37:46 2013
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
MarkForUpload: True
ProcCmdline: compiz
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x7fc3c29c457e: mov 0x8(%rsi),%rax
 PC (0x7fc3c29c457e) ok
 source "0x8(%rsi)" (0xd63d3d3dd63e3e46) not located in a known VMA region (needed readable region)!
 destination "%rax" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 ?? () from /usr/lib/compiz/libunityshell.so
 ?? () from /usr/lib/compiz/libunityshell.so
 g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
Title: compiz crashed with SIGSEGV in g_main_context_dispatch()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm admin audio cdrom dialout floppy fuse lpadmin netdev plugdev powerdev sambashare scanner tomcat6 video