Unity8 (QtMir) crashed on login with SIGSEGV in deref() from qtmir::serializeMimeData()

[roberto]

crashes on login
black screen

ProblemType: Crash
DistroRelease: Ubuntu 16.04
Package: unity8 8.11+16.04.20160308-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-12.28-generic 4.4.4
Uname: Linux 4.4.0-12-generic x86_64
ApportVersion: 2.20-0ubuntu3
Architecture: amd64
Date: Sat Mar 12 00:16:50 2016
ExecutablePath: /usr/bin/unity8
InstallationDate: Installed on 2015-11-15 (117 days ago)
InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Alpha amd64 (20150924)
ProcCmdline: unity8
ProcEnviron:
 LANGUAGE=it
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
Signal: 11
SourcePackage: unity8
StacktraceTop:
 ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqpa-mirserver.so
 ?? () from /usr/lib/x86_64-linux-gnu/libmirserver.so.38
 ?? () from /usr/lib/x86_64-linux-gnu/libmirserver.so.38
 TiledDisplayConfigurationPolicy::apply_to(mir::graphics::DisplayConfiguration&) () from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqpa-mirserver.so
 ?? () from /usr/lib/x86_64-linux-gnu/libmirserver.so.38
Title: unity8 crashed with SIGSEGV in TiledDisplayConfigurationPolicy::apply_to()
UpgradeStatus: Upgraded to xenial on 2016-02-19 (20 days ago)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo

[Apport retracing service (apport)]

StacktraceTop:
 deref (this=0x7f883fdaf920) at /usr/include/x86_64-linux-gnu/qt5/QtCore/qrefcount.h:65
 ~QByteArray (this=0x0, __in_chrg=<optimized out>) at /usr/include/x86_64-linux-gnu/qt5/QtCore/qbytearray.h:459
 qtmir::serializeMimeData (mimeData=0x7f8849398f30 <mir::graphics::nested::NestedDisplayConfiguration::<lambda(MirDisplayOutput&)>::operator()(MirDisplayOutput &) const+656>) at /build/qtmir-gles-atu9Uh/qtmir-gles-0.4.7+16.04.20160310.1/src/platforms/mirserver/clipboard.cpp:73
 ?? ()
 ?? ()

[Albert Astals Cid (aacid)]

The ThreadStacktrace looks weird

#2 qtmir::serializeMimeData (mimeData=0x7f8849398f30 <mir::graphics::nested::NestedDisplayConfiguration::<lambda(MirDisplayOutput&)>::operator()(MirDisplayOutput &) const+656>) at /build/qtmir-gles-atu9Uh/qtmir-gles-0.4.7+16.04.20160310.1/src/platforms/mirserver/clipboard.cpp:73
....
#29 qtmir::serializeMimeData (mimeData=0x7f883404cae0) at /build/qtmir-gles-atu9Uh/qtmir-gles-0.4.7+16.04.20160310.1/src/platforms/mirserver/clipboard.cpp:75

I don't see how clipboard.cpp:75 can call anything that makes us end again in the same function :/

[Daniel van Vugt (vanvugt)]

That kind of stack trace confusion sometimes means some private/local/inline function has been called. And it shows the nearest public function instead.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.