compiz crashed with SIGSEGV in unity::ui::EdgeBarrierController::Impl::OnPointerBarrierEvent()

got this while zoomed out (super +s ) and moving the firefox browser window around between workspaces

if you need any more debug info please le tme know

daz

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: unity 5.10.0-0ubuntu3
ProcVersionSignature: Ubuntu 3.2.0-23.36-generic 3.2.14
Uname: Linux 3.2.0-23-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.0.1-0ubuntu3
Architecture: amd64
Date: Sat Apr 14 10:50:42 2012
Disassembly: => 0x0: Cannot access memory at address 0x0
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=en_US:en
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x0: Cannot access memory at address 0x0
 PC (0x00000000) not located in a known VMA region (needed executable region)!
SegvReason: executing NULL VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 ?? ()
 unity::ui::EdgeBarrierController::Impl::OnPointerBarrierEvent(unity::ui::PointerBarrierWrapper*, std::shared_ptr<unity::ui::BarrierEvent>) () from /usr/lib/compiz/libunityshell.so
 sigc::internal::slot_call2<sigc::bound_mem_functor2<void, unity::ui::EdgeBarrierController::Impl, unity::ui::PointerBarrierWrapper*, std::shared_ptr<unity::ui::BarrierEvent> >, void, unity::ui::PointerBarrierWrapper*, std::shared_ptr<unity::ui::BarrierEvent> >::call_it(sigc::internal::slot_rep*, unity::ui::PointerBarrierWrapper* const&, std::shared_ptr<unity::ui::BarrierEvent> const&) () from /usr/lib/compiz/libunityshell.so
 unity::ui::PointerBarrierWrapper::EmitCurrentData() () from /usr/lib/compiz/libunityshell.so
 ?? () from /usr/lib/compiz/libunityshell.so
Title: compiz crashed with SIGSEGV in unity::ui::EdgeBarrierController::Impl::OnPointerBarrierEvent()
UpgradeStatus: No upgrade log present (probably fresh install)
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