At least I think that's what's happening.
I got this crash on boot while testing the unlock-device script that unity8 provides (which basically just reboots and unlocks the greeter).
I'll attach the .crash file, but here's the stacktrace:
Core was generated by `unity-system-compositor --spinner=/usr/bin/unity-system-compositor-spinner --fi'.
Program terminated with signal SIGABRT, Aborted.
#0 __libc_do_syscall ()
at ../ports/sysdeps/unix/sysv/linux/arm/libc-do-syscall.S:44
44 ../ports/sysdeps/unix/sysv/linux/arm/libc-do-syscall.S: No such file or directory.
(gdb) bt
#0 __libc_do_syscall ()
at ../ports/sysdeps/unix/sysv/linux/arm/libc-do-syscall.S:44
#1 0xb67eb05e in __GI_raise (sig=sig@entry=6)
at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
#2 0xb67ebd4e in __GI_abort () at abort.c:89
#3 0xb67e62b8 in __assert_fail_base (
fmt=0x1 <error: Cannot access memory at address 0x1>,
assertion=0xb6ba10f4 "!pending_client_notifications.empty()",
assertion@entry=0x0,
file=0xb6ba0ff0 "/build/buildd/mir-0.5.0+14.10.20140722/src/server/compositor/buffer_queue.cpp", file@entry=0xb4a53000 "\001", line=136,
line@entry=3062534324,
function=function@entry=0xb6ba0cf4 <mir::compositor::BufferQueue::BufferQueue(int, std::shared_ptr<mir::graphics::GraphicBufferAllocator> const&, mir::graphics::BufferProperties const&, mir::compositor::FrameDroppingPolicyFactory const&)::{lambda()#1}::operator()() const::__PRETTY_FUNCTION__> "mir::compositor::BufferQueue::BufferQueue(int, const std::shared_ptr<mir::graphics::GraphicBufferAllocator>&, const mir::graphics::BufferProperties&, const mir::compositor::FrameDroppingPolicyFactory&"...) at assert.c:92
#4 0xb67e634e in __GI___assert_fail (assertion=0x0, file=0xb4a53000 "\001",
line=3062534324,
function=0xb6ba0cf4 <mir::compositor::BufferQueue::BufferQueue(int, std::shared_ptr<mir::graphics::GraphicBufferAllocator> const&, mir::graphics::BufferProperties const&, mir::compositor::FrameDroppingPolicyFactory const&)::{lambda()#1}::operator()() const::__PRETTY_FUNCTION__> "mir::compositor::BufferQueue::BufferQueue(int, const std::shared_ptr<mir::graphics::GraphicBufferAllocator>&, const mir::graphics::BufferProperties&, const mir::compositor::FrameDroppingPolicyFactory&"...) at assert.c:101
#5 0xb6b03f6a in operator() (__closure=0xb68a90b4 <lock>)
at /build/buildd/mir-0.5.0+14.10.20140722/src/server/compositor/buffer_queue.cpp:136
#6 std::_Function_handler<void(), mir::compositor::BufferQueue::BufferQueue(int, const std::shared_ptr<mir::graphics::GraphicBufferAllocator>&, const mir::graphics::BufferProperties&, const mir::compositor::FrameDroppingPolicyFactory&)::<lambda()> >::_M_invoke(const std::_Any_data &) (__functor=...)
at /usr/include/c++/4.9/functional:2039
#7 0xb6b02eec in operator() (this=0xae4018ac)
at /usr/include/c++/4.9/functional:2439
#8 operator() (__closure=0xae4018a8)
at /build/buildd/mir-0.5.0+14.10.20140722/src/server/compositor/timeout_frame_dropping_policy_factory.cpp:59
#9 std::_Function_handler<void(), (anonymous namespace)::TimeoutFrameDroppingPolicy::TimeoutFrameDroppingPolicy(const std::shared_ptr<mir::time::Timer>&, std::chrono::milliseconds, std::function<void()>)::<lambda()> >::_M_invoke(const std::_Any_data &) (__functor=...) at /usr/include/c++/4.9/functional:2039
#10 0xb6aea5ac in operator() (ec=..., __closure=<optimized out>)
at /build/buildd/mir-0.5.0+14.10.20140722/src/server/asio_main_loop.cpp:390
#11 std::_Function_handler<void(const boost::system::error_code&), (anonymous namespace)::make_handler(std::weak_ptr<(anonymous namespace)::AlarmImpl::InternalState>)::<lambda(const boost::system::error_code&)> >::_M_invoke(const std::_Any_data &, const boost::system::error_code &) (__functor=..., __args#0=...)
at /usr/include/c++/4.9/functional:2039
#12 0xb6aefb20 in operator() (__args#0=..., this=0xbea21ac4)
at /usr/include/c++/4.9/functional:2439
#13 operator() (this=0xbea21ac4)
at /usr/include/boost/asio/detail/bind_handler.hpp:47
#14 asio_handler_invoke<boost::asio::detail::binder1<std::function<void(const boost::system::error_code&)>, boost::system::error_code> > (function=...)
at /usr/include/boost/asio/handler_invoke_hook.hpp:69
#15 invoke<boost::asio::detail::binder1<std::function<void(const boost::system::error_code&)>, boost::system::error_code>, std::function<void(const boost::system::error_code&)> > (context=..., function=...)
at /usr/include/boost/asio/detail/handler_invoke_helpers.hpp:37
#16 boost::asio::detail::wait_handler<std::function<void (boost::system::error_code const&)> >::do_complete(boost::asio::detail::task_io_service*, boost::asio::detail::task_io_service_operation*, boost::system::error_code const&, unsigned int) (owner=0x88, base=<optimized out>)
at /usr/include/boost/asio/detail/wait_handler.hpp:70
#17 0xb6aee2f6 in complete (bytes_transferred=<optimized out>, ec=...,
owner=..., this=0xae4039f0)
at /usr/include/boost/asio/detail/task_io_service_operation.hpp:38
#18 do_run_one (ec=..., this_thread=..., lock=..., this=0x147d7a0)
at /usr/include/boost/asio/detail/impl/task_io_service.ipp:384
#19 boost::asio::detail::task_io_service::run (this=0x147d7a0, ec=...)
at /usr/include/boost/asio/detail/impl/task_io_service.ipp:153
#20 0xb6aea404 in run (this=<optimized out>)
at /usr/include/boost/asio/impl/io_service.ipp:59
#21 mir::AsioMainLoop::run (this=<optimized out>)
at /build/buildd/mir-0.5.0+14.10.20140722/src/server/asio_main_loop.cpp:261
#22 0xb6ae391e in mir::DisplayServer::run (this=this@entry=0xbea21bf8)
at /build/buildd/mir-0.5.0+14.10.20140722/src/server/display_server.cpp:223
#23 0xb6ae1434 in mir::run_mir(mir::ServerConfiguration&, std::function<void (mir::DisplayServer&)>) (config=..., init=...)
at /build/buildd/mir-0.5.0+14.10.20140722/src/server/run_mir.cpp:93
#24 0x00037d16 in usc::SystemCompositor::run() ()
#25 0x0002f158 in main ()
Also on a separate boot, an almost identical stacktrace from unity8 this time:
Core was generated by `unity8'. sysdeps/ unix/sysv/ linux/arm/ libc-do- syscall. S:44 sysdeps/ unix/sysv/ linux/raise. c:56 0xb437d0f4 "!pending_ client_ notifications. empty() ", entry=0x0, buildd/ mir-0.5. 0+14.10. 20140722/ src/server/ compositor/ buffer_ queue.cpp" , file@entry= 0xb4612220 "\001", line=136, entry=305636984 4, function@ entry=0xb437ccf 4 <mir::composito r::BufferQueue: :BufferQueue( int, std::shared_ ptr<mir: :graphics: :GraphicBufferA llocator> const&, mir::graphics: :BufferProperti es const&, mir::compositor ::FrameDropping PolicyFactory const&) ::{lambda( )#1}::operator( )() const:: __PRETTY_ FUNCTION_ _> "mir::composito r::BufferQueue: :BufferQueue( int, const std::shared_ ptr<mir: :graphics: :GraphicBufferA llocator> &, const mir::graphics: :BufferProperti es&, const mir::compositor ::FrameDropping PolicyFactory& "...) at assert.c:92 3056369844, 0xb437ccf4 <mir::composito r::BufferQueue: :BufferQueue( int, std::shared_ ptr<mir: :graphics: :GraphicBufferA llocator> const&, mir::graphics: :BufferProperti es const&, mir::compositor ::FrameDropping PolicyFactory const&) ::{lambda( )#1}::operator( )() const:: __PRETTY_ FUNCTION_ _> "mir::composito r::BufferQueue: :BufferQueue( int, const std::shared_ ptr<mir: :graphics: :GraphicBufferA llocator> &, const mir::graphics: :BufferProperti es&, const mir::compositor ::FrameDropping PolicyFactory& "...) at assert.c:101 0xb62c80b4 <lock>) buildd/ mir-0.5. 0+14.10. 20140722/ src/server/ compositor/ buffer_ queue.cpp: 136 handler< void(), mir::compositor ::BufferQueue: :BufferQueue( int, const std::shared_ ptr<mir: :graphics: :GraphicBufferA llocator> &, const mir::graphics: :BufferProperti es&, const mir::compositor ::FrameDropping PolicyFactory& )::<lambda( )> >::_M_invoke(const std::_Any_data &) (__functor=...) c++/4.9/ functional: 2039 c++/4.9/ functional: 2439 0x9d71b778) buildd/ mir-0.5. 0+14.10. 20140722/ src/server/ compositor/ timeout_ frame_dropping_ policy_ factory. cpp:59 handler< void(), (anonymous namespace) ::TimeoutFrameD roppingPolicy: :TimeoutFrameDr oppingPolicy( const std::shared_ ptr<mir: :time:: Timer>& , std::chrono: :milliseconds, std::function< void()> )::<lambda( )> >::_M_invoke(const std::_Any_data &) (__functor=...) at /usr/include/ c++/4.9/ functional: 2039 <optimized out>) buildd/ mir-0.5. 0+14.10. 20140722/ src/server/ asio_main_ loop.cpp: 390 handler< void(const boost:: system: :error_ code&), (anonymous namespace) ::make_ handler( std::weak_ ptr<(anonymous ...
Program terminated with signal SIGABRT, Aborted.
#0 __libc_do_syscall ()
at ../ports/
#1 0xb620a05e in __GI_raise (sig=sig@entry=6)
at ../nptl/
#2 0xb620ad4e in __GI_abort () at abort.c:89
#3 0xb62052b8 in __assert_fail_base (
fmt=0x1 <error: Cannot access memory at address 0x1>,
assertion=
assertion@
file=0xb437cff0 "/build/
line@
function=
#4 0xb620534e in __GI___assert_fail (assertion=0x0, file=0xb4612220 "\001",
line=
function=
#5 0xb42dff6a in operator() (__closure=
at /build/
#6 std::_Function_
at /usr/include/
#7 0xb42deeec in operator() (this=0x9d71b77c)
at /usr/include/
#8 operator() (__closure=
at /build/
#9 std::_Function_
#10 0xb42c65ac in operator() (ec=..., __closure=
at /build/
#11 std::_Function_