Application: systemsettings5 (5.4.1)

Qt Version: 5.4.2
Operating System: Linux 4.2.0-17-generic x86_64
Distribution: Ubuntu 15.10

-- Information about the crash:
- What I was doing when the application crashed:
I used the system settings/file associations to try to associate text files in particular t-c++hdr and t-c++src files with emacs 24.  I didn't read any help files and something happened that makes my file manager unusable.

- Unusual behavior I noticed:
I can bring up the file manager,  and I can even run the cursor over folders, but when I touch a file the file manager disappears.  I looked for mimeapps.list and couldn't find it. I installed Ubuntu Tweak and it showed associations once, and now doesn't even start after the little icon bounces a few times.  If I go into system settings, file associations, the system immediately informs me of a crash.  I tried removing kubuntu-desktop and reinstalling, but it didn't correct my user associations.  Maybe there should be some more protection so that when a user tries to use the file associations application, he can't put something in that causes a segmentation fault.  My bad.  I know.  Sorry.  Probably have to reinstall Kubuntu 15.10.  How to save my files without a file manager?  Arrgghhh.
- Custom settings of the application:

The crash can be reproduced every time.

-- Backtrace:
Application: System Settings (systemsettings5), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f54dbd72800 (LWP 3854))]

Thread 2 (Thread 0x7f54ca8e8700 (LWP 3855)):
#0  0x00007f54d85118dd in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f54d6221bd2 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f54d622374f in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f54cce36a39 in QXcbEventReader::run (this=0x7254f0) at qxcbconnection.cpp:1105
#4  0x00007f54d8c042be in QThreadPrivate::start (arg=0x7254f0) at thread/qthread_unix.cpp:337
#5  0x00007f54d59ac6aa in start_thread (arg=0x7f54ca8e8700) at pthread_create.c:333
#6  0x00007f54d851ceed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f54dbd72800 (LWP 3854)):
[KCrash Handler]
#6  operator== (s1=..., s2=...) at tools/qstring.cpp:2521
#7  0x00007f54d8e6ebb6 in operator!= (s2=..., s1=...) at ../../include/QtCore/../../src/corelib/tools/qstring.h:587
#8  QMimeBinaryProvider::loadMimeTypePrivate (this=<optimized out>, data=...) at mimetypes/qmimeprovider.cpp:626
#9  0x00007f54d8e623ba in QMimeType::comment (this=this@entry=0x12d6820) at mimetypes/qmimetype.cpp:223
#10 0x00007f54bb53c6af in MimeTypeData::initFromQMimeType (this=this@entry=0x12d6820) at ../../keditfiletype/mimetypedata.cpp:89
#11 0x00007f54bb53e055 in MimeTypeData::MimeTypeData (this=0x12d6820, mime=...) at ../../keditfiletype/mimetypedata.cpp:63
#12 0x00007f54bb539949 in TypesListItem::TypesListItem (this=0x12d67e0, parent=<optimized out>, mimetype=...) at ../../keditfiletype/typeslistitem.cpp:38
#13 0x00007f54bb5333f4 in FileTypesView::readFileTypes (this=this@entry=0xb9c430) at ../../keditfiletype/filetypesview.cpp:203
#14 0x00007f54bb5336f8 in FileTypesView::load (this=0xb9c430) at ../../keditfiletype/filetypesview.cpp:464
#15 0x00007f54daf54499 in KCModule::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at moc_kcmodule.cpp:107
#16 0x00007f54d8e15651 in QObject::event (this=this@entry=0xb9c430, e=e@entry=0xc155d0) at kernel/qobject.cpp:1245
#17 0x00007f54da2a9edb in QWidget::event (this=0xb9c430, event=0xc155d0) at kernel/qwidget.cpp:9084
#18 0x00007f54da267b8c in QApplicationPrivate::notify_helper (this=this@entry=0x70d800, receiver=receiver@entry=0xb9c430, e=e@entry=0xc155d0) at kernel/qapplication.cpp:3720
#19 0x00007f54da26d230 in QApplication::notify (this=0x7ffc89d4a3b0, receiver=0xb9c430, e=0xc155d0) at kernel/qapplication.cpp:3503
#20 0x00007f54d8de3f1b in QCoreApplication::notifyInternal (this=0x7ffc89d4a3b0, receiver=0xb9c430, event=event@entry=0xc155d0) at kernel/qcoreapplication.cpp:935
#21 0x00007f54d8de6057 in QCoreApplication::sendEvent (event=0xc155d0, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:228
#22 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x70cf60) at kernel/qcoreapplication.cpp:1552
#23 0x00007f54d8de6588 in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at kernel/qcoreapplication.cpp:1410
#24 0x00007f54d8e3ae73 in postEventSourceDispatch (s=0x7575c0) at kernel/qeventdispatcher_glib.cpp:271
#25 0x00007f54d548cff7 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#26 0x00007f54d548d250 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#27 0x00007f54d548d2fc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#28 0x00007f54d8e3b27f in QEventDispatcherGlib::processEvents (this=0x7575a0, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#29 0x00007f54d8de175a in QEventLoop::exec (this=this@entry=0x7ffc89d4a290, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#30 0x00007f54d8de92cc in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1188
#31 0x00007f54d9cb400c in QGuiApplication::exec () at kernel/qguiapplication.cpp:1510
#32 0x00007f54da264025 in QApplication::exec () at kernel/qapplication.cpp:2956
#33 0x000000000040f04b in main (argc=1, argv=<optimized out>) at ../../app/main.cpp:55

Reported using DrKonqi