compiz crashed with SIGSEGV in unity::switcher::Controller::Impl::GetCurrentSelection()

[Akshay Bhat]

Screen froze when I was trying to switch between work-spaces.

ProblemType: Crash
DistroRelease: Ubuntu 16.04
Package: compiz-core 1:0.9.12.2+16.04.20160415-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
Uname: Linux 4.4.0-21-generic x86_64
.tmp.unity_support_test.0:

ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Mon May 2 12:02:46 2016
DistUpgraded: 2016-04-25 10:06:45,569 DEBUG icon theme changed, re-reading
DistroCodename: xenial
DistroVariant: ubuntu
DkmsStatus:
 backfire, 0.84-2, 4.2.0-35-generic, x86_64: installedError! Could not locate dkms.conf file.
 File: does not exist.

 backfire, 0.84-2, 4.4.0-21-generic, x86_64: installed
ExecutablePath: /usr/bin/compiz
GraphicsCard:
 Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06) (prog-if 00 [VGA controller])
   Subsystem: CLEVO/KAPOK Computer 4th Gen Core Processor Integrated Graphics Controller [1558:0655]
MachineType: System76, Inc. Gazelle Professional
ProcCmdline: compiz
ProcEnviron:
 PATH=(custom, user)
 SHELL=/bin/bash
 LANG=en_US.UTF-8
 LANGUAGE=en_US
 XDG_RUNTIME_DIR=<set>
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-21-generic root=UUID=fd2a1529-14bd-4e1d-bb45-13cd9cbe5651 ro quiet splash vt.handoff=7
SegvAnalysis:
 Segfault happened at: 0x7f2e071c8c63 <_ZNK5unity8switcher10Controller4Impl19GetCurrentSelectionEv+339>: mov (%rdi),%rbp
 PC (0x7f2e071c8c63) ok
 source "(%rdi)" (0x00000000) not located in a known VMA region (needed readable region)!
 destination "%rbp" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: compiz
StacktraceTop:
 unity::switcher::Controller::Impl::GetCurrentSelection() const () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
 unity::switcher::Controller::Impl::Hide(bool) () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
 unity::UnityScreen::altTabTerminateCommon(CompAction*, unsigned int, std::vector<CompOption, std::allocator<CompOption> >&) () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
 compiz::private_screen::EventManager::triggerRelease(CompAction*, unsigned int, std::vector<CompOption, std::allocator<CompOption> >&) () from /usr/lib/x86_64-linux-gnu/libcompiz_core.so.ABI-20151010
 PrivateScreen::triggerStateNotifyBindings(std::vector<CompOption, std::allocator<CompOption> >&, std::vector<CompAction, std::allocator<CompAction> >&, _XkbStateNotifyEvent*, std::vector<CompOption, std::allocator<CompOption> >&) () from /usr/lib/x86_64-linux-gnu/libcompiz_core.so.ABI-20151010
Title: compiz crashed with SIGSEGV in unity::switcher::Controller::Impl::GetCurrentSelection()
UpgradeStatus: Upgraded to xenial on 2016-04-25 (7 days ago)
UserGroups: adm cdrom dialout dip lpadmin plugdev sambashare sudo vboxusers
dmi.bios.date: 07/28/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 1.03.06RS761
dmi.board.asset.tag: Tag 12345
dmi.board.name: Gazelle Professional
dmi.board.vendor: System76, Inc.
dmi.board.version: gazp9b
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 9
dmi.chassis.vendor: System76, Inc.
dmi.chassis.version: gazp9b
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1.03.06RS761:bd07/28/2014:svnSystem76,Inc.:pnGazelleProfessional:pvrgazp9b:rvnSystem76,Inc.:rnGazelleProfessional:rvrgazp9b:cvnSystem76,Inc.:ct9:cvrgazp9b:
dmi.product.name: Gazelle Professional
dmi.product.version: gazp9b
dmi.sys.vendor: System76, Inc.
version.compiz: compiz 1:0.9.12.2+16.04.20160415-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.67-1
version.libgl1-mesa-dri: libgl1-mesa-dri 11.2.0-1ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 11.2.0-1ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.18.3-1ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.1-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-1build2
xserver.bootTime: Mon Apr 25 10:07:11 2016
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 5563
 vendor CMN
xserver.version: 2:1.18.3-1ubuntu2

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1540012, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.