Bug 396346 - Discover crashes upon launch
Summary: Discover crashes upon launch
Status: RESOLVED UPSTREAM
Alias: None
Product: Discover
Classification: Applications
Component: discover (show other bugs)
Version: 5.13.2
Platform: Neon Linux
: NOR crash
Target Milestone: ---
Assignee: Aleix Pol
URL:
Keywords: drkonqi
: 395762 (view as bug list)
Depends on:
Blocks:
 
Reported: 2018-07-09 20:33 UTC by Øystein Steffensen-Alværvik
Modified: 2018-10-09 11:04 UTC (History)
2 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


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Description Øystein Steffensen-Alværvik 2018-07-09 20:33:33 UTC
Application: plasma-discover (5.13.2)

Qt Version: 5.11.0
Frameworks Version: 5.47.0
Operating System: Linux 4.15.0-24-generic x86_64
Distribution: KDE neon User Edition 5.13

-- Information about the crash:
- What I was doing when the application crashed:
Launched Discover after changing the system colour scheme. Had also recently removed a global menu, but unsure if it's related.

I triggered the crash two times. The second was a freeze – attaching gdb backtrace in next comment .

The crash can be reproduced sometimes.

-- Backtrace:
Application: Oppdag (plasma-discover), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
[Current thread is 1 (Thread 0x7f6bf8ff98c0 (LWP 1898))]

Thread 15 (Thread 0x7f6b8f7fe700 (LWP 1926)):
#0  0x00007f6bf42cf4d9 in syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007f6beef52cfa in g_cond_wait_until (cond=cond@entry=0x2775798, mutex=mutex@entry=0x2775790, end_time=end_time@entry=11076969876) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread-posix.c:1441
#2  0x00007f6beeee2999 in g_async_queue_pop_intern_unlocked (queue=queue@entry=0x2775790, wait=wait@entry=1, end_time=end_time@entry=11076969876) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gasyncqueue.c:422
#3  0x00007f6beeee2fbb in g_async_queue_timeout_pop (queue=0x2775790, timeout=timeout@entry=15000000) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gasyncqueue.c:543
#4  0x00007f6beef3560a in g_thread_pool_thread_proxy () at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthreadpool.c:167
#5  0x00007f6beef3560a in g_thread_pool_thread_proxy (data=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthreadpool.c:364
#6  0x00007f6beef34bb5 in g_thread_proxy (data=0x7f6b7c0024f0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread.c:780
#7  0x00007f6bf0d736ba in start_thread (arg=0x7f6b8f7fe700) at pthread_create.c:333
#8  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 14 (Thread 0x7f6b96ffd700 (LWP 1921)):
#0  0x00007f6bf0d79709 in pthread_cond_timedwait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:225
#1  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x56fd9c0) at thread/qwaitcondition_unix.cpp:133
#2  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x56fd9c0) at thread/qwaitcondition_unix.cpp:141
#3  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (this=this@entry=0x56fd240, mutex=mutex@entry=0x3834ca0, time=30000) at thread/qwaitcondition_unix.cpp:215
#4  0x00007f6bf4cc7e8a in QThreadPoolThread::run() (this=0x56fd230) at thread/qthreadpool.cpp:146
#5  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x56fd230) at thread/qthread_unix.cpp:367
#6  0x00007f6bf0d736ba in start_thread (arg=0x7f6b96ffd700) at pthread_create.c:333
#7  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 13 (Thread 0x7f6b97fff700 (LWP 1918)):
[KCrash Handler]
#6  0x00007f6bb3b5fa13 in _flatpak_dir_ensure_repo (self=self@entry=0x0, allow_empty=allow_empty@entry=0, cancellable=cancellable@entry=0x33bc110 [GCancellable], error=error@entry=0x7f6b97ffec00) at common/flatpak-dir.c:1601
#7  0x00007f6bb3b70c4f in flatpak_dir_list_remote_refs (error=0x7f6b97ffec00, cancellable=0x33bc110 [GCancellable], self=0x0) at common/flatpak-dir.c:1706
#8  0x00007f6bb3b70c4f in flatpak_dir_list_remote_refs (self=self@entry=0x0, remote=remote@entry=0x7f6b80183280 "kdeapps", refs=refs@entry=0x7f6b97ffeb28, cancellable=cancellable@entry=0x33bc110 [GCancellable], error=error@entry=0x7f6b97ffec00) at common/flatpak-dir.c:9490
#9  0x00007f6bb3b5952d in flatpak_installation_list_remote_refs_sync (self=self@entry=0x33d25a0, remote_name=0x7f6b80183280 "kdeapps", cancellable=cancellable@entry=0x33bc110 [GCancellable], error=error@entry=0x7f6b97ffec00) at lib/flatpak-installation.c:1795
#10 0x00007f6bb3b59718 in flatpak_installation_list_installed_refs_for_update (self=0x33d25a0, cancellable=cancellable@entry=0x33bc110 [GCancellable], error=error@entry=0x7f6b97ffec58) at lib/flatpak-installation.c:840
#11 0x00007f6bb3dea225 in QtConcurrent::RunFunctionTask<_GPtrArray*>::run() (__closure=0x5756848) at /workspace/build/libdiscover/backends/FlatpakBackend/FlatpakBackend.cpp:736
#12 0x00007f6bb3dea225 in QtConcurrent::RunFunctionTask<_GPtrArray*>::run() (this=0x5756820) at /usr/include/x86_64-linux-gnu/qt5/QtConcurrent/qtconcurrentstoredfunctioncall.h:60
#13 0x00007f6bb3dea225 in QtConcurrent::RunFunctionTask<_GPtrArray*>::run() (this=0x5756820) at /usr/include/x86_64-linux-gnu/qt5/QtConcurrent/qtconcurrentrunbase.h:108
#14 0x00007f6bf4cc7bc7 in QThreadPoolThread::run() (this=0x56fb9b0) at thread/qthreadpool.cpp:101
#15 0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x56fb9b0) at thread/qthread_unix.cpp:367
#16 0x00007f6bf0d736ba in start_thread (arg=0x7f6b97fff700) at pthread_create.c:333
#17 0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 12 (Thread 0x7f6ba9af5700 (LWP 1912)):
#0  0x00007f6bf42c974d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f6beef0e38c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7f6b9c004da0, timeout=<optimized out>, context=0x7f6b9c000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007f6beef0e38c in g_main_context_iterate (context=context@entry=0x7f6b9c000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007f6beef0e49c in g_main_context_iteration (context=0x7f6b9c000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007f6bf4ee9beb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f6b9c0008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007f6bf4e911ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f6ba9af4cf0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007f6bf4cc65e4 in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:522
#7  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x25030e0) at thread/qthread_unix.cpp:367
#8  0x00007f6bf0d736ba in start_thread (arg=0x7f6ba9af5700) at pthread_create.c:333
#9  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 11 (Thread 0x7f6baad27700 (LWP 1911)):
#0  0x00007f6bf0d79709 in pthread_cond_timedwait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:225
#1  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x7f6ba0003110) at thread/qwaitcondition_unix.cpp:133
#2  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x7f6ba0003110) at thread/qwaitcondition_unix.cpp:141
#3  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (this=this@entry=0x7f6ba0002e20, mutex=mutex@entry=0x7f6ba0002b30, time=30000) at thread/qwaitcondition_unix.cpp:215
#4  0x00007f6bf4cc7e8a in QThreadPoolThread::run() (this=0x7f6ba0002e10) at thread/qthreadpool.cpp:146
#5  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x7f6ba0002e10) at thread/qthread_unix.cpp:367
#6  0x00007f6bf0d736ba in start_thread (arg=0x7f6baad27700) at pthread_create.c:333
#7  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 10 (Thread 0x7f6bab528700 (LWP 1910)):
#0  0x00007f6beef52a79 in g_mutex_lock (mutex=mutex@entry=0x7f6ba0000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread-posix.c:1335
#1  0x00007f6beef0e488 in g_main_context_iteration (context=0x7f6ba0000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3900
#2  0x00007f6bf4ee9beb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f6ba00008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#3  0x00007f6bf4e911ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f6bab527cf0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#4  0x00007f6bf4cc65e4 in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:522
#5  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x385b6d0) at thread/qthread_unix.cpp:367
#6  0x00007f6bf0d736ba in start_thread (arg=0x7f6bab528700) at pthread_create.c:333
#7  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 9 (Thread 0x7f6bb1495700 (LWP 1909)):
#0  0x00007f6bf0d79709 in pthread_cond_timedwait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:225
#1  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x3835e60) at thread/qwaitcondition_unix.cpp:133
#2  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x3835e60) at thread/qwaitcondition_unix.cpp:141
#3  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (this=this@entry=0x3467c00, mutex=mutex@entry=0x3834ca0, time=30000) at thread/qwaitcondition_unix.cpp:215
#4  0x00007f6bf4cc7e8a in QThreadPoolThread::run() (this=0x3467bf0) at thread/qthreadpool.cpp:146
#5  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x3467bf0) at thread/qthread_unix.cpp:367
#6  0x00007f6bf0d736ba in start_thread (arg=0x7f6bb1495700) at pthread_create.c:333
#7  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 8 (Thread 0x7f6bb1c96700 (LWP 1908)):
#0  0x00007f6bf0d79709 in pthread_cond_timedwait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:225
#1  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x3468000) at thread/qwaitcondition_unix.cpp:133
#2  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (time=30000, this=0x3468000) at thread/qwaitcondition_unix.cpp:141
#3  0x00007f6bf4cd255f in QWaitCondition::wait(QMutex*, unsigned long) (this=this@entry=0x3464d20, mutex=mutex@entry=0x3834ca0, time=30000) at thread/qwaitcondition_unix.cpp:215
#4  0x00007f6bf4cc7e8a in QThreadPoolThread::run() (this=0x3464d10) at thread/qthreadpool.cpp:146
#5  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x3464d10) at thread/qthread_unix.cpp:367
#6  0x00007f6bf0d736ba in start_thread (arg=0x7f6bb1c96700) at pthread_create.c:333
#7  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 7 (Thread 0x7f6bc102c700 (LWP 1906)):
#0  0x00007f6bf8ec2ce0 in __GI___tls_get_addr (ti=0x7f6bf5315670) at dl-tls.c:832
#1  0x00007f6bf4cd06d6 in QThreadData::current(bool) () at thread/qthread_unix.cpp:184
#2  0x00007f6bf4cd06d6 in QThreadData::current(bool) (createIfNecessary=createIfNecessary@entry=true) at thread/qthread_unix.cpp:239
#3  0x00007f6bf4ee9ff1 in postEventSourceCheck(GSource*) (timeout=0x0, s=0x7f6bb80012d0) at kernel/qeventdispatcher_glib.cpp:252
#4  0x00007f6bf4ee9ff1 in postEventSourceCheck(GSource*) (source=0x7f6bb80012d0) at kernel/qeventdispatcher_glib.cpp:269
#5  0x00007f6beef0ddc1 in g_main_context_check (context=context@entry=0x7f6bb8000990, max_priority=2147483647, fds=fds@entry=0x7f6bb8002870, n_fds=n_fds@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3681
#6  0x00007f6beef0e330 in g_main_context_iterate (context=context@entry=0x7f6bb8000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3837
#7  0x00007f6beef0e49c in g_main_context_iteration (context=0x7f6bb8000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#8  0x00007f6bf4ee9beb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f6bb80008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#9  0x00007f6bf4e911ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f6bc102bcf0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#10 0x00007f6bf4cc65e4 in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:522
#11 0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x206d940) at thread/qthread_unix.cpp:367
#12 0x00007f6bf0d736ba in start_thread (arg=0x7f6bc102c700) at pthread_create.c:333
#13 0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 6 (Thread 0x7f6bc182d700 (LWP 1905)):
#0  0x00007f6beef52a79 in g_mutex_lock (mutex=mutex@entry=0x27760a0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread-posix.c:1335
#1  0x00007f6beef0db41 in g_main_context_query (context=context@entry=0x27760a0, max_priority=2147483647, timeout=timeout@entry=0x7f6bc182cd04, fds=fds@entry=0x7f6bb40010c0, n_fds=n_fds@entry=2) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3544
#2  0x00007f6beef0e307 in g_main_context_iterate (context=0x27760a0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3822
#3  0x00007f6beef0e712 in g_main_loop_run (loop=0x2776030) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4034
#4  0x00007f6bc32059d6 in gdbus_shared_thread_func (user_data=0x2776070) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./gio/gdbusprivate.c:246
#5  0x00007f6beef34bb5 in g_thread_proxy (data=0x273bcf0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread.c:780
#6  0x00007f6bf0d736ba in start_thread (arg=0x7f6bc182d700) at pthread_create.c:333
#7  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 5 (Thread 0x7f6bc202e700 (LWP 1904)):
#0  0x00007f6beef52a94 in g_mutex_unlock (mutex=0x2775880) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread-posix.c:1347
#1  0x00007f6beef0d9a0 in g_main_context_prepare (context=context@entry=0x2775880, priority=priority@entry=0x7f6bc202dd10) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3507
#2  0x00007f6beef0e2bb in g_main_context_iterate (context=context@entry=0x2775880, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3820
#3  0x00007f6beef0e49c in g_main_context_iteration (context=0x2775880, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007f6beef0e4d9 in glib_worker_main (data=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:5672
#5  0x00007f6beef34bb5 in g_thread_proxy (data=0x273bca0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread.c:780
#6  0x00007f6bf0d736ba in start_thread (arg=0x7f6bc202e700) at pthread_create.c:333
#7  0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7f6bcc113700 (LWP 1903)):
#0  0x00007f6bf42c974d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f6beef0e38c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7f6bc40013c0, timeout=<optimized out>, context=0x7f6bc4000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007f6beef0e38c in g_main_context_iterate (context=context@entry=0x7f6bc4000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007f6beef0e49c in g_main_context_iteration (context=0x7f6bc4000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007f6bf4ee9beb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f6bc40008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007f6bf4e911ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f6bcc112c80, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007f6bf4cc65e4 in QThread::exec() (this=this@entry=0x26afa40) at thread/qthread.cpp:522
#7  0x00007f6bf810ee66 in QQuickPixmapReader::run() (this=0x26afa40) at util/qquickpixmapcache.cpp:934
#8  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x26afa40) at thread/qthread_unix.cpp:367
#9  0x00007f6bf0d736ba in start_thread (arg=0x7f6bcc113700) at pthread_create.c:333
#10 0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7f6bd7fff700 (LWP 1902)):
#0  0x00007f6bf42c974d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f6beef0e38c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7f6bd0002e70, timeout=<optimized out>, context=0x7f6bd0000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007f6beef0e38c in g_main_context_iterate (context=context@entry=0x7f6bd0000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007f6beef0e49c in g_main_context_iteration (context=0x7f6bd0000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007f6bf4ee9beb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f6bd00008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007f6bf4e911ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f6bd7ffecd0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007f6bf4cc65e4 in QThread::exec() (this=this@entry=0x20cc030) at thread/qthread.cpp:522
#7  0x00007f6bf584ecf5 in QQmlThreadPrivate::run() (this=0x20cc030) at qml/ftw/qqmlthread.cpp:148
#8  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x20cc030) at thread/qthread_unix.cpp:367
#9  0x00007f6bf0d736ba in start_thread (arg=0x7f6bd7fff700) at pthread_create.c:333
#10 0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7f6bdd30d700 (LWP 1901)):
#0  0x00007f6bf42c974d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f6beef0e38c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7f6bd8018ad0, timeout=<optimized out>, context=0x7f6bd8000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007f6beef0e38c in g_main_context_iterate (context=context@entry=0x7f6bd8000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007f6beef0e49c in g_main_context_iteration (context=0x7f6bd8000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007f6bf4ee9beb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f6bd80008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007f6bf4e911ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f6bdd30ccc0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007f6bf4cc65e4 in QThread::exec() (this=this@entry=0x7f6bf6e7fd60 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread.cpp:522
#7  0x00007f6bf6c06f35 in QDBusConnectionManager::run() (this=0x7f6bf6e7fd60 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at qdbusconnection.cpp:178
#8  0x00007f6bf4cd1727 in QThreadPrivate::start(void*) (arg=0x7f6bf6e7fd60 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:367
#9  0x00007f6bf0d736ba in start_thread (arg=0x7f6bdd30d700) at pthread_create.c:333
#10 0x00007f6bf42d541d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f6bf8ff98c0 (LWP 1898)):
#0  0x00007f6bf0d79360 in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f6bf4cd25cb in QWaitCondition::wait(QMutex*, unsigned long) (time=18446744073709551615, this=0x3834cf0) at thread/qwaitcondition_unix.cpp:143
#2  0x00007f6bf4cd25cb in QWaitCondition::wait(QMutex*, unsigned long) (this=this@entry=0x3834cc8, mutex=mutex@entry=0x3834ca0, time=time@entry=18446744073709551615) at thread/qwaitcondition_unix.cpp:215
#3  0x00007f6bf4cc70a5 in QThreadPoolPrivate::waitForDone(int) (this=this@entry=0x3834c30, msecs=msecs@entry=-1) at thread/qthreadpool.cpp:317
#4  0x00007f6bf4cc7481 in QThreadPool::waitForDone(int) (this=this@entry=0x3464968, msecs=msecs@entry=-1) at thread/qthreadpool.cpp:691
#5  0x00007f6bf4cc74bc in QThreadPool::~QThreadPool() (this=0x3464968, __in_chrg=<optimized out>) at thread/qthreadpool.cpp:471
#6  0x00007f6bb3de4622 in FlatpakBackend::~FlatpakBackend() (this=0x3464910, __in_chrg=<optimized out>) at /workspace/build/libdiscover/backends/FlatpakBackend/FlatpakBackend.cpp:102
#7  0x00007f6bb3de4729 in FlatpakBackend::~FlatpakBackend() (this=0x3464910, __in_chrg=<optimized out>) at /workspace/build/libdiscover/backends/FlatpakBackend/FlatpakBackend.cpp:109
#8  0x00007f6bf7d985ae in ResourcesModel::~ResourcesModel() (end=<optimized out>, begin=0x38d0fd0) at /usr/include/x86_64-linux-gnu/qt5/QtCore/qalgorithms.h:320
#9  0x00007f6bf7d985ae in ResourcesModel::~ResourcesModel() (c=...) at /usr/include/x86_64-linux-gnu/qt5/QtCore/qalgorithms.h:328
#10 0x00007f6bf7d985ae in ResourcesModel::~ResourcesModel() (this=0x214b7b0, __in_chrg=<optimized out>) at /workspace/build/libdiscover/resources/ResourcesModel.cpp:93
#11 0x00007f6bf7d98609 in ResourcesModel::~ResourcesModel() (this=0x214b7b0, __in_chrg=<optimized out>) at /workspace/build/libdiscover/resources/ResourcesModel.cpp:94
#12 0x00007f6bf4ec0c00 in QObject::event(QEvent*) (this=0x214b7b0, e=<optimized out>) at kernel/qobject.cpp:1242
#13 0x00007f6bf64e829c in QApplicationPrivate::notify_helper(QObject*, QEvent*) (this=<optimized out>, receiver=0x214b7b0, e=0x58ba210) at kernel/qapplication.cpp:3713
#14 0x00007f6bf64ef917 in QApplication::notify(QObject*, QEvent*) (this=0x7ffe92792d50, receiver=0x214b7b0, e=0x58ba210) at kernel/qapplication.cpp:3472
#15 0x00007f6bf4e92e38 in QCoreApplication::notifyInternal2(QObject*, QEvent*) (receiver=0x214b7b0, event=event@entry=0x58ba210) at kernel/qcoreapplication.cpp:1048
#16 0x00007f6bf4e95a3e in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (event=0x58ba210, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:234
#17 0x00007f6bf4e95a3e in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (receiver=receiver@entry=0x0, event_type=event_type@entry=52, data=0x20219f0) at kernel/qcoreapplication.cpp:1745
#18 0x00007f6bf4e95eb8 in QCoreApplication::sendPostedEvents(QObject*, int) (receiver=receiver@entry=0x0, event_type=event_type@entry=52) at kernel/qcoreapplication.cpp:1599
#19 0x00007f6bf4e95f01 in QCoreApplicationPrivate::execCleanup() (this=<optimized out>) at kernel/qcoreapplication.cpp:1358
#20 0x00007f6bf4e9a2ec in QCoreApplication::exec() () at kernel/qcoreapplication.cpp:1340
#21 0x00007f6bf5cd981c in QGuiApplication::exec() () at kernel/qguiapplication.cpp:1751
#22 0x00007f6bf64e81f5 in QApplication::exec() () at kernel/qapplication.cpp:2898
#23 0x00000000004130df in main(int, char**) (argc=1, argv=<optimized out>) at /workspace/build/discover/main.cpp:156

Reported using DrKonqi
Comment 1 Øystein Steffensen-Alværvik 2018-07-09 20:37:00 UTC
GDB backtrace of the reproduction (freeze). Note that I attached GDB after Discover started to 'freeze'. Hope it's still helpful.

GNU gdb (Ubuntu 7.11.1-0ubuntu1~16.5) 7.11.1
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word".
(gdb) handle SIG33 pass nostop noprint
Signal        Stop	Print	Pass to program	Description
SIG33         No	No	Yes		Real-time event 33
(gdb) set pagination 0
(gdb) attach 2379
Attaching to process 2379
[New LWP 2380]
[New LWP 2381]
[New LWP 2382]
[New LWP 2383]
[New LWP 2384]
[New LWP 2385]
[New LWP 2386]
[New LWP 2389]
[New LWP 2391]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
38	../sysdeps/unix/sysv/linux/x86_64/syscall.S: No such file or directory.
(gdb) backtrace full
#0  0x00007fbbb78734d9 in syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007fbbb8266355 in QBasicMutex::lockInternal() (val3=0, addr2=0x0, val2=0, val=3, op=0, addr=<optimized out>) at thread/qfutex_p.h:92
#2  0x00007fbbb8266355 in QBasicMutex::lockInternal() (expectedValue=<optimized out>, futex=...) at thread/qfutex_p.h:107
#3  0x00007fbbb8266355 in QBasicMutex::lockInternal() (timeout=-1, elapsedTimer=0x0, d_ptr=...) at thread/qmutex_linux.cpp:145
#4  0x00007fbbb8266355 in QBasicMutex::lockInternal() (this=0x7fbbb88beb90 <_q_ObjectMutexPool+304>) at thread/qmutex_linux.cpp:162
#5  0x00007fbbb82663b7 in QMutex::lock() (this=this@entry=0x7fbbb88beb90 <_q_ObjectMutexPool+304>) at thread/qmutex.cpp:229
        current = 0x1
#6  0x00007fbbb846731d in QMetaObjectPrivate::disconnect(QObject const*, int, QMetaObject const*, QObject const*, int, void**, QMetaObjectPrivate::DisconnectType) (mtx2=0x7fbbb88beb90 <_q_ObjectMutexPool+304>, mtx1=0x7fbbb88bed60 <_q_ObjectMutexPool+768>) at ../../include/QtCore/5.11.0/QtCore/private/../../../../../src/corelib/thread/qorderedmutexlocker_p.h:109
        mtx2 = 0x7fbbb88beb90 <_q_ObjectMutexPool+304>
        mtx1 = 0x7fbbb88bed60 <_q_ObjectMutexPool+768>
        needToUnlock = false
        receiverMutex = <optimized out>
        success = <optimized out>
        c = <optimized out>
        s = 0x0
        locker = {val = 140444231789921}
        connectionLists = <optimized out>
        success = false
#7  0x00007fbbb846731d in QMetaObjectPrivate::disconnect(QObject const*, int, QMetaObject const*, QObject const*, int, void**, QMetaObjectPrivate::DisconnectType) (slot=0x0, disconnectType=QMetaObjectPrivate::DisconnectAll, senderMutex=0x7fbbb88bed60 <_q_ObjectMutexPool+768>, method_index=<optimized out>, receiver=0x2b03c00, c=0x17b2f30) at kernel/qobject.cpp:3377
        needToUnlock = false
        receiverMutex = <optimized out>
        success = <optimized out>
        c = <optimized out>
        s = 0x0
        locker = {val = 140444231789921}
        connectionLists = <optimized out>
        success = false
#8  0x00007fbbb846731d in QMetaObjectPrivate::disconnect(QObject const*, int, QMetaObject const*, QObject const*, int, void**, QMetaObjectPrivate::DisconnectType) (sender=sender@entry=0x4714650, signal_index=signal_index@entry=10, smeta=<optimized out>, receiver=receiver@entry=0x2b03c00, method_index=method_index@entry=39, disconnectType=disconnectType@entry=QMetaObjectPrivate::DisconnectAll, slot=0x0) at kernel/qobject.cpp:3445
        c = <optimized out>
        s = 0x4714650
        locker = {val = 140444231789921}
        connectionLists = <optimized out>
        success = false
#9  0x00007fbbb8467d24 in QObject::disconnect(QObject const*, char const*, QObject const*, char const*) (sender=0x4714650, signal=0x4aeada9 "Finished(uint,uint)", receiver=0x2b03c00, method=0x4ab1319 "finished(uint,uint)") at kernel/qobject.cpp:3022
        method_index = 39
        rmeta = 0x7fbb8727c7a0 <PackageKit::Transaction::staticMetaObject>
        signal_index = 10
        signal_arg = 0x7fbb8706b4e8 "2Finished(uint,uint)"
        signal_name = {d = 0x4aead90}
        signal_found = true
        method_name = {d = 0x4ab1300}
        method_arg = 0x7fbb8706b548 "1finished(uint,uint)"
        membcode = <optimized out>
        method_found = false
        res = false
        smeta = 0x7fbb8727c960 <OrgFreedesktopPackageKitTransactionInterface::staticMetaObject>
        signalName = {d = 0x2c83d30}
        signalTypes = {a = 10, s = 2, ptr = 0x7fffd667a5c0, {array = "\003\000\000\000\000\000\000\000\020\026\257\002\000\000\000\000\003\000\000\000\000\000\000\000\300\t\257\002\000\000\000\000\060\250g\326\377\177\000\000\204a\177\267\273\177\000\000\000\000\000\000\000\000\000\000t\000\000\000\000\000\000\000.\000\000\000\000\000\000\000\315m'\270\273\177\000\000-\000\000\000\000\000\000\000\060\250g\326\377\177\000\000 \000\000\000\000\000\000\000\023\304.\270\273\177\000\000\023\000\000\000\000\000\000\000,\000\000\000\000\000\000\000\000\250g\326\377\177\000\000W\312.\270\273\177\000\000\000\000\000\000\000\000\000\000.\025\257\002\000\000\000", q_for_alignment_1 = 3, q_for_alignment_2 = 1.4821969375237396e-323}}
        methodName = {d = 0x2c11550}
        methodTypes = {a = 10, s = 2, ptr = 0x7fffd667a670, {array = "\003\000\000\000\000\000\000\000`\024\257\002\000\000\000\000\003\000\000\000\000\000\000\000\260\360\247\004\000\000\000\000,\000\000\000,\000\000\000 k\263\267\273\177\000\000t\000\000\000\000\000\000\000\b\000\000\000\000\000\000\000h0\300\004\000\000\000\000\001\000\000\000\000\000\000\000P\251\005\207\273\177\000\000\204a\177\267\273\177\000\000\000\250g\326\377\177\000\000\000\000\000\000\000\000\000\000.\000\000\000\000\000\000\000\315m'\270\273\177\000\000-\000\000\000\000\000\000\000\200\247g\326\377\177\000\000-\000\000\000\000\000\000\000\023\304.\270\273\177\000", q_for_alignment_1 = 3, q_for_alignment_2 = 1.4821969375237396e-323}}
#10 0x00007fbb870574ab in PackageKit::TransactionPrivate::setupSignal(QString const&, bool) () at /usr/lib/x86_64-linux-gnu/libpackagekitqt5.so.0
#11 0x00007fbb8705aaf9 in PackageKit::Transaction::disconnectNotify(char const*) () at /usr/lib/x86_64-linux-gnu/libpackagekitqt5.so.0
#12 0x00007fbb87056f0a in PackageKit::Transaction::disconnectNotify(QMetaMethod const&) () at /usr/lib/x86_64-linux-gnu/libpackagekitqt5.so.0
#13 0x00007fbbb846b993 in QObject::~QObject() (this=<optimized out>, __in_chrg=<optimized out>) at kernel/qobject.cpp:988
        slotObj = <optimized out>
        sender = 0x2b03c00
        senderLists = <optimized out>
        locker = {val = 140444231789457}
        node = 0x2af14c0
        d = <optimized out>
#14 0x00007fbb872b626b in TransactionSet::~TransactionSet() (this=0x2afc960, __in_chrg=<optimized out>) at /workspace/build/obj-x86_64-linux-gnu/libdiscover/backends/PackageKitBackend/../../../../libdiscover/backends/PackageKitBackend/TransactionSet.h:28
#15 0x00007fbb872b626b in TransactionSet::~TransactionSet() (this=0x2afc960, __in_chrg=<optimized out>) at /workspace/build/obj-x86_64-linux-gnu/libdiscover/backends/PackageKitBackend/../../../../libdiscover/backends/PackageKitBackend/TransactionSet.h:28
#16 0x00007fbbb8464c00 in QObject::event(QEvent*) (this=0x2afc960, e=<optimized out>) at kernel/qobject.cpp:1242
#17 0x00007fbbb9a8c29c in QApplicationPrivate::notify_helper(QObject*, QEvent*) (this=<optimized out>, receiver=0x2afc960, e=0x17adc10) at kernel/qapplication.cpp:3713
        consumed = <optimized out>
        this = <optimized out>
        e = 0x17adc10
        receiver = 0x2afc960
#18 0x00007fbbb9a93917 in QApplication::notify(QObject*, QEvent*) (this=0x7fffd667af70, receiver=0x2afc960, e=0x17adc10) at kernel/qapplication.cpp:3472
        w = 0x2afc960
        extra = <optimized out>
        isProxyWidget = <optimized out>
        res = false
#19 0x00007fbbb8436e38 in QCoreApplication::notifyInternal2(QObject*, QEvent*) (receiver=0x2afc960, event=event@entry=0x17adc10) at kernel/qcoreapplication.cpp:1048
        selfRequired = true
        result = false
        cbdata = {0x2afc960, 0x17adc10, 0x7fffd667ab6f}
        d = <optimized out>
        threadData = 0x132a9f0
        scopeLevelCounter = {threadData = 0x132a9f0}
#20 0x00007fbbb8439a3e in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (event=0x17adc10, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:234
        e = 0x17adc10
        pe = <optimized out>
        r = <optimized out>
        unlocker = {m = <synthetic pointer>}
        event_deleter = {d = 0x17adc10}
        locker = {val = 20097568}
        startOffset = 0
        i = @0x132aa14: 2
        cleanup = {receiver = 0x0, event_type = 0, data = 0x132a9f0, exceptionCaught = true}
#21 0x00007fbbb8439a3e in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x132a9f0) at kernel/qcoreapplication.cpp:1745
        e = 0x17adc10
        pe = <optimized out>
        r = <optimized out>
        unlocker = {m = <synthetic pointer>}
        event_deleter = {d = 0x17adc10}
        locker = {val = 20097568}
        startOffset = 0
        i = @0x132aa14: 2
        cleanup = {receiver = 0x0, event_type = 0, data = 0x132a9f0, exceptionCaught = true}
#22 0x00007fbbb8439eb8 in QCoreApplication::sendPostedEvents(QObject*, int) (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at kernel/qcoreapplication.cpp:1599
        data = <optimized out>
#23 0x00007fbbb848e5c3 in postEventSourceDispatch(GSource*, GSourceFunc, gpointer) (s=0x137e1d0) at kernel/qeventdispatcher_glib.cpp:276
        source = 0x137e1d0
#24 0x00007fbbb24b2197 in g_main_context_dispatch (context=0x7fbba40016f0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3154
        dispatch = 0x7fbbb848e5b0 <postEventSourceDispatch(GSource*, GSourceFunc, gpointer)>
        prev_source = 0x0
        was_in_call = 0
        user_data = 0x0
        callback = 0x0
        cb_funcs = <optimized out>
        cb_data = <optimized out>
        need_destroy = <optimized out>
        source = 0x137e1d0
        current = 0x138ac10
        i = 0
#25 0x00007fbbb24b2197 in g_main_context_dispatch (context=context@entry=0x7fbba40016f0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3769
#26 0x00007fbbb24b23f0 in g_main_context_iterate (context=context@entry=0x7fbba40016f0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3840
        max_priority = 0
        timeout = 0
        some_ready = 1
        nfds = <optimized out>
        allocated_nfds = 6
        fds = 0x49fd100
#27 0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbba40016f0, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
        retval = <optimized out>
#28 0x00007fbbb848dbcf in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x1370e50, flags=...) at kernel/qeventdispatcher_glib.cpp:423
        d = 0x1372860
        canWait = true
        savedFlags = {i = 0}
        result = <optimized out>
#29 0x00007fbbac11cc11 in QPAEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x1370e50, flags=...) at qeventdispatcher_glib.cpp:69
        didSendEvents = <optimized out>
#30 0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fffd667ae90, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
        d = 0x13ddca0
        locker = {val = 20097760}
        ref = {d = 0x13ddca0, locker = @0x7fffd667ae10, exceptionCaught = true}
#31 0x00007fbbb843e2d4 in QCoreApplication::exec() () at kernel/qcoreapplication.cpp:1336
        threadData = 0x132a9f0
        eventLoop = {<QObject> = {_vptr.QObject = 0x7fbbb88b73c8 <vtable for QEventLoop+16>, static staticMetaObject = {d = {superdata = 0x0, stringdata = 0x7fbbb85c0300 <qt_meta_stringdata_QObject>, data = 0x7fbbb85c01e0 <qt_meta_data_QObject>, static_metacall = 0x7fbbb846bcd0 <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x13ddca0}, static staticQtMetaObject = {d = {superdata = 0x0, stringdata = 0x7fbbb85c30c0 <qt_meta_stringdata_Qt>, data = 0x7fbbb85c0420 <qt_meta_data_Qt>, static_metacall = 0x0, relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0x7fbbb88afa40 <QObject::staticMetaObject>, stringdata = 0x7fbbb85bade0 <qt_meta_stringdata_QEventLoop>, data = 0x7fbbb85bad80 <qt_meta_data_QEventLoop>, static_metacall = 0x7fbbb8434f00 <QEventLoop::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}
        returnCode = <optimized out>
#32 0x00007fbbb927d81c in QGuiApplication::exec() () at kernel/qguiapplication.cpp:1751
#33 0x00007fbbb9a8c1f5 in QApplication::exec() () at kernel/qapplication.cpp:2898
#34 0x00000000004130df in main(int, char**) (argc=1, argv=<optimized out>) at /workspace/build/discover/main.cpp:156
        app = {<QGuiApplication> = {<QCoreApplication> = {<QObject> = {_vptr.QObject = 0x7fbbba165a10 <vtable for QApplication+16>, static staticMetaObject = {d = {superdata = 0x0, stringdata = 0x7fbbb85c0300 <qt_meta_stringdata_QObject>, data = 0x7fbbb85c01e0 <qt_meta_data_QObject>, static_metacall = 0x7fbbb846bcd0 <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x132af80}, static staticQtMetaObject = {d = {superdata = 0x0, stringdata = 0x7fbbb85c30c0 <qt_meta_stringdata_Qt>, data = 0x7fbbb85c0420 <qt_meta_data_Qt>, static_metacall = 0x0, relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0x7fbbb88afa40 <QObject::staticMetaObject>, stringdata = 0x7fbbb85bb420 <qt_meta_stringdata_QCoreApplication>, data = 0x7fbbb85bb300 <qt_meta_data_QCoreApplication>, static_metacall = 0x7fbbb8438960 <QCoreApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, static self = 0x7fffd667af70}, static staticMetaObject = {d = {superdata = 0x7fbbb88b7560 <QCoreApplication::staticMetaObject>, stringdata = 0x7fbbb9635e60 <qt_meta_stringdata_QGuiApplication>, data = 0x7fbbb9635be0 <qt_meta_data_QGuiApplication>, static_metacall = 0x7fbbb9288b30 <QGuiApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0x7fbbb991d120 <QGuiApplication::staticMetaObject>, stringdata = 0x7fbbb9e0ba40 <qt_meta_stringdata_QApplication>, data = 0x7fbbb9e0b8c0 <qt_meta_data_QApplication>, static_metacall = 0x7fbbb9a91380 <QApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}
        about = {d = 0x140fdf0}
        mainWindow = 0x13de560
(gdb) info registers
rax            0xfffffffffffffe00	-512
rbx            0x7fbbb88beb90	140444231789456
rcx            0x7fbbb78734d9	140444214703321
rdx            0x3	3
rsi            0x80	128
rdi            0x7fbbb88beb90	140444231789456
rbp            0x3	0x3
rsp            0x7fffd667a368	0x7fffd667a368
r8             0x0	0
r9             0x0	0
r10            0x0	0
r11            0x246	582
r12            0x7fbbb88bed60	140444231789920
r13            0x0	0
r14            0x7fbbb88bea60	140444231789152
r15            0x17b2f30	24850224
rip            0x7fbbb78734d9	0x7fbbb78734d9 <syscall+25>
eflags         0x246	[ PF ZF IF ]
cs             0x33	51
ss             0x2b	43
ds             0x0	0
es             0x0	0
fs             0x0	0
gs             0x0	0
(gdb) x/16i $pc
=> 0x7fbbb78734d9 <syscall+25>:	cmp    $0xfffffffffffff001,%rax
   0x7fbbb78734df <syscall+31>:	jae    0x7fbbb78734e2 <syscall+34>
   0x7fbbb78734e1 <syscall+33>:	retq   
   0x7fbbb78734e2 <syscall+34>:	mov    0x2c298f(%rip),%rcx        # 0x7fbbb7b35e78
   0x7fbbb78734e9 <syscall+41>:	neg    %eax
   0x7fbbb78734eb <syscall+43>:	mov    %eax,%fs:(%rcx)
   0x7fbbb78734ee <syscall+46>:	or     $0xffffffffffffffff,%rax
   0x7fbbb78734f2 <syscall+50>:	retq   
   0x7fbbb78734f3:	nopw   %cs:0x0(%rax,%rax,1)
   0x7fbbb78734fd:	nopl   (%rax)
   0x7fbbb7873500 <daemon>:	push   %r12
   0x7fbbb7873502 <daemon+2>:	push   %rbp
   0x7fbbb7873503 <daemon+3>:	mov    %edi,%r12d
   0x7fbbb7873506 <daemon+6>:	push   %rbx
   0x7fbbb7873507 <daemon+7>:	mov    %esi,%ebp
   0x7fbbb7873509 <daemon+9>:	sub    $0x90,%rsp
(gdb) thread apply all backtrace

Thread 10 (Thread 0x7fbb69430700 (LWP 2391)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7fbb60004da0, timeout=<optimized out>, context=0x7fbb60000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=context@entry=0x7fbb60000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbb60000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007fbbb848dbeb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fbb600008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fbb6942fcf0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007fbbb826a5e4 in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:522
#7  0x00007fbbb8275727 in QThreadPrivate::start(void*) (arg=0x1837700) at thread/qthread_unix.cpp:367
#8  0x00007fbbb43176ba in start_thread (arg=0x7fbb69430700) at pthread_create.c:333
#9  0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 9 (Thread 0x7fbb6ae63700 (LWP 2389)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=2, fds=0x7fbb6400eef0, timeout=<optimized out>, context=0x7fbb64000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=context@entry=0x7fbb64000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbb64000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007fbbb848dbeb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fbb640008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fbb6ae62cf0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007fbbb826a5e4 in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:522
#7  0x00007fbbb8275727 in QThreadPrivate::start(void*) (arg=0x2b581e0) at thread/qthread_unix.cpp:367
#8  0x00007fbbb43176ba in start_thread (arg=0x7fbb6ae63700) at pthread_create.c:333
#9  0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 8 (Thread 0x7fbb7ffff700 (LWP 2386)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7fbb74002870, timeout=<optimized out>, context=0x7fbb74000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=context@entry=0x7fbb74000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbb74000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007fbbb848dbcf in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fbb740008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#5  0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fbb7fffecf0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007fbbb826a5e4 in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:522
#7  0x00007fbbb8275727 in QThreadPrivate::start(void*) (arg=0x19d8340) at thread/qthread_unix.cpp:367
#8  0x00007fbbb43176ba in start_thread (arg=0x7fbb7ffff700) at pthread_create.c:333
#9  0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 7 (Thread 0x7fbb84f4e700 (LWP 2385)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=2, fds=0x7fbb780010c0, timeout=<optimized out>, context=0x19c8190) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=0x19c8190, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b2712 in g_main_loop_run (loop=0x19c8120) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4034
#4  0x00007fbb869269d6 in gdbus_shared_thread_func (user_data=0x19c8160) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./gio/gdbusprivate.c:246
#5  0x00007fbbb24d8bb5 in g_thread_proxy (data=0x19a18f0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread.c:780
#6  0x00007fbbb43176ba in start_thread (arg=0x7fbb84f4e700) at pthread_create.c:333
#7  0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 6 (Thread 0x7fbb8574f700 (LWP 2384)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7fbb800008c0, timeout=<optimized out>, context=0x19c7970) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=context@entry=0x19c7970, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b249c in g_main_context_iteration (context=0x19c7970, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007fbbb24b24d9 in glib_worker_main (data=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:5672
#5  0x00007fbbb24d8bb5 in g_thread_proxy (data=0x19a18a0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gthread.c:780
#6  0x00007fbbb43176ba in start_thread (arg=0x7fbb8574f700) at pthread_create.c:333
#7  0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 5 (Thread 0x7fbb8f7c9700 (LWP 2383)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7fbb880013c0, timeout=<optimized out>, context=0x7fbb88000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=context@entry=0x7fbb88000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbb88000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007fbbb848dbeb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fbb880008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fbb8f7c8c80, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007fbbb826a5e4 in QThread::exec() (this=this@entry=0x1930c40) at thread/qthread.cpp:522
#7  0x00007fbbbb6b2e66 in QQuickPixmapReader::run() (this=0x1930c40) at util/qquickpixmapcache.cpp:934
#8  0x00007fbbb8275727 in QThreadPrivate::start(void*) (arg=0x1930c40) at thread/qthread_unix.cpp:367
#9  0x00007fbbb43176ba in start_thread (arg=0x7fbb8f7c9700) at pthread_create.c:333
#10 0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7fbb9b5ef700 (LWP 2382)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7fbb94002e70, timeout=<optimized out>, context=0x7fbb94000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=context@entry=0x7fbb94000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbb94000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007fbbb848dbcf in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fbb940008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#5  0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fbb9b5eecd0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007fbbb826a5e4 in QThread::exec() (this=this@entry=0x13e0060) at thread/qthread.cpp:522
#7  0x00007fbbb8df2cf5 in QQmlThreadPrivate::run() (this=0x13e0060) at qml/ftw/qqmlthread.cpp:148
#8  0x00007fbbb8275727 in QThreadPrivate::start(void*) (arg=0x13e0060) at thread/qthread_unix.cpp:367
#9  0x00007fbbb43176ba in start_thread (arg=0x7fbb9b5ef700) at pthread_create.c:333
#10 0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7fbba0896700 (LWP 2381)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb24b238c in g_main_context_iterate (priority=2147483647, n_fds=4, fds=0x7fbb9c018ad0, timeout=<optimized out>, context=0x7fbb9c000990) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:4135
#2  0x00007fbbb24b238c in g_main_context_iterate (context=context@entry=0x7fbb9c000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3835
#3  0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbb9c000990, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#4  0x00007fbbb848dbeb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fbb9c0008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fbba0895cc0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#6  0x00007fbbb826a5e4 in QThread::exec() (this=this@entry=0x7fbbba423d60 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread.cpp:522
#7  0x00007fbbba1aaf35 in QDBusConnectionManager::run() (this=0x7fbbba423d60 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at qdbusconnection.cpp:178
#8  0x00007fbbb8275727 in QThreadPrivate::start(void*) (arg=0x7fbbba423d60 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:367
#9  0x00007fbbb43176ba in start_thread (arg=0x7fbba0896700) at pthread_create.c:333
#10 0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7fbba967f700 (LWP 2380)):
#0  0x00007fbbb786d74d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fbbb224fc62 in _xcb_conn_wait (__timeout=-1, __nfds=1, __fds=0x7fbba967ebf0) at /usr/include/x86_64-linux-gnu/bits/poll2.h:46
#2  0x00007fbbb224fc62 in _xcb_conn_wait (c=c@entry=0x133b5a0, cond=cond@entry=0x133b5e0, vector=vector@entry=0x0, count=count@entry=0x0) at ../../src/xcb_conn.c:459
#3  0x00007fbbb22518d7 in xcb_wait_for_event (c=0x133b5a0) at ../../src/xcb_in.c:693
#4  0x00007fbbac094029 in QXcbEventReader::run() (this=0x13465f0) at qxcbconnection.cpp:1384
#5  0x00007fbbb8275727 in QThreadPrivate::start(void*) (arg=0x13465f0) at thread/qthread_unix.cpp:367
#6  0x00007fbbb43176ba in start_thread (arg=0x7fbba967f700) at pthread_create.c:333
#7  0x00007fbbb787941d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7fbbbc59d8c0 (LWP 2379)):
#0  0x00007fbbb78734d9 in syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007fbbb8266355 in QBasicMutex::lockInternal() (val3=0, addr2=0x0, val2=0, val=3, op=0, addr=<optimized out>) at thread/qfutex_p.h:92
#2  0x00007fbbb8266355 in QBasicMutex::lockInternal() (expectedValue=<optimized out>, futex=...) at thread/qfutex_p.h:107
#3  0x00007fbbb8266355 in QBasicMutex::lockInternal() (timeout=-1, elapsedTimer=0x0, d_ptr=...) at thread/qmutex_linux.cpp:145
#4  0x00007fbbb8266355 in QBasicMutex::lockInternal() (this=0x7fbbb88beb90 <_q_ObjectMutexPool+304>) at thread/qmutex_linux.cpp:162
#5  0x00007fbbb82663b7 in QMutex::lock() (this=this@entry=0x7fbbb88beb90 <_q_ObjectMutexPool+304>) at thread/qmutex.cpp:229
#6  0x00007fbbb846731d in QMetaObjectPrivate::disconnect(QObject const*, int, QMetaObject const*, QObject const*, int, void**, QMetaObjectPrivate::DisconnectType) (mtx2=0x7fbbb88beb90 <_q_ObjectMutexPool+304>, mtx1=0x7fbbb88bed60 <_q_ObjectMutexPool+768>) at ../../include/QtCore/5.11.0/QtCore/private/../../../../../src/corelib/thread/qorderedmutexlocker_p.h:109
#7  0x00007fbbb846731d in QMetaObjectPrivate::disconnect(QObject const*, int, QMetaObject const*, QObject const*, int, void**, QMetaObjectPrivate::DisconnectType) (slot=0x0, disconnectType=QMetaObjectPrivate::DisconnectAll, senderMutex=0x7fbbb88bed60 <_q_ObjectMutexPool+768>, method_index=<optimized out>, receiver=0x2b03c00, c=0x17b2f30) at kernel/qobject.cpp:3377
#8  0x00007fbbb846731d in QMetaObjectPrivate::disconnect(QObject const*, int, QMetaObject const*, QObject const*, int, void**, QMetaObjectPrivate::DisconnectType) (sender=sender@entry=0x4714650, signal_index=signal_index@entry=10, smeta=<optimized out>, receiver=receiver@entry=0x2b03c00, method_index=method_index@entry=39, disconnectType=disconnectType@entry=QMetaObjectPrivate::DisconnectAll, slot=0x0) at kernel/qobject.cpp:3445
#9  0x00007fbbb8467d24 in QObject::disconnect(QObject const*, char const*, QObject const*, char const*) (sender=0x4714650, signal=0x4aeada9 "Finished(uint,uint)", receiver=0x2b03c00, method=0x4ab1319 "finished(uint,uint)") at kernel/qobject.cpp:3022
#10 0x00007fbb870574ab in PackageKit::TransactionPrivate::setupSignal(QString const&, bool) () at /usr/lib/x86_64-linux-gnu/libpackagekitqt5.so.0
#11 0x00007fbb8705aaf9 in PackageKit::Transaction::disconnectNotify(char const*) () at /usr/lib/x86_64-linux-gnu/libpackagekitqt5.so.0
#12 0x00007fbb87056f0a in PackageKit::Transaction::disconnectNotify(QMetaMethod const&) () at /usr/lib/x86_64-linux-gnu/libpackagekitqt5.so.0
#13 0x00007fbbb846b993 in QObject::~QObject() (this=<optimized out>, __in_chrg=<optimized out>) at kernel/qobject.cpp:988
#14 0x00007fbb872b626b in TransactionSet::~TransactionSet() (this=0x2afc960, __in_chrg=<optimized out>) at /workspace/build/obj-x86_64-linux-gnu/libdiscover/backends/PackageKitBackend/../../../../libdiscover/backends/PackageKitBackend/TransactionSet.h:28
#15 0x00007fbb872b626b in TransactionSet::~TransactionSet() (this=0x2afc960, __in_chrg=<optimized out>) at /workspace/build/obj-x86_64-linux-gnu/libdiscover/backends/PackageKitBackend/../../../../libdiscover/backends/PackageKitBackend/TransactionSet.h:28
#16 0x00007fbbb8464c00 in QObject::event(QEvent*) (this=0x2afc960, e=<optimized out>) at kernel/qobject.cpp:1242
#17 0x00007fbbb9a8c29c in QApplicationPrivate::notify_helper(QObject*, QEvent*) (this=<optimized out>, receiver=0x2afc960, e=0x17adc10) at kernel/qapplication.cpp:3713
#18 0x00007fbbb9a93917 in QApplication::notify(QObject*, QEvent*) (this=0x7fffd667af70, receiver=0x2afc960, e=0x17adc10) at kernel/qapplication.cpp:3472
#19 0x00007fbbb8436e38 in QCoreApplication::notifyInternal2(QObject*, QEvent*) (receiver=0x2afc960, event=event@entry=0x17adc10) at kernel/qcoreapplication.cpp:1048
#20 0x00007fbbb8439a3e in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (event=0x17adc10, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:234
#21 0x00007fbbb8439a3e in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x132a9f0) at kernel/qcoreapplication.cpp:1745
#22 0x00007fbbb8439eb8 in QCoreApplication::sendPostedEvents(QObject*, int) (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at kernel/qcoreapplication.cpp:1599
#23 0x00007fbbb848e5c3 in postEventSourceDispatch(GSource*, GSourceFunc, gpointer) (s=0x137e1d0) at kernel/qeventdispatcher_glib.cpp:276
#24 0x00007fbbb24b2197 in g_main_context_dispatch (context=0x7fbba40016f0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3154
#25 0x00007fbbb24b2197 in g_main_context_dispatch (context=context@entry=0x7fbba40016f0) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3769
#26 0x00007fbbb24b23f0 in g_main_context_iterate (context=context@entry=0x7fbba40016f0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3840
#27 0x00007fbbb24b249c in g_main_context_iteration (context=0x7fbba40016f0, may_block=may_block@entry=1) at /build/glib2.0-prJhLS/glib2.0-2.48.2/./glib/gmain.c:3901
#28 0x00007fbbb848dbcf in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x1370e50, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#29 0x00007fbbac11cc11 in QPAEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x1370e50, flags=...) at qeventdispatcher_glib.cpp:69
#30 0x00007fbbb84351ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fffd667ae90, flags=..., flags@entry=...) at kernel/qeventloop.cpp:214
#31 0x00007fbbb843e2d4 in QCoreApplication::exec() () at kernel/qcoreapplication.cpp:1336
#32 0x00007fbbb927d81c in QGuiApplication::exec() () at kernel/qguiapplication.cpp:1751
#33 0x00007fbbb9a8c1f5 in QApplication::exec() () at kernel/qapplication.cpp:2898
#34 0x00000000004130df in main(int, char**) (argc=1, argv=<optimized out>) at /workspace/build/discover/main.cpp:156
(gdb) quit
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	Inferior 1 [process 2379] will be detached.

Quit anyway? (y or n) y
Detaching from program: /usr/bin/plasma-discover, process 2379
Comment 2 Aleix Pol 2018-08-03 14:34:42 UTC
This is an issue upstream in Flatpak. Will send them in case they can see to fixing it.
Comment 3 Aleix Pol 2018-10-09 11:04:47 UTC
*** Bug 395762 has been marked as a duplicate of this bug. ***