#0  0xf670205b in KSycocaEntry::name (this=0x0) at /srcbuild/kf5-kservice/src/sycoca/ksycocaentry.cpp:104
#1  0xef18f064 in MostUsedModel::data (this=0x567e8b70, index=..., role=0) at /srcbuild/systemsettings/sidebar/SidebarMode.cpp:181
#2  0xf50a7a4a in QModelIndex::data (arole=0, this=0xffffa540) at /opt/include/QtCore/qabstractitemmodel.h:432

$ gdb systemsettings5 
GNU gdb (Ubuntu 8.0-0ubuntu1) 8.0
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Reading symbols from systemsettings5...Reading symbols from /usr/lib/debug/.build-id/f9/37a8ac61d1d395775f46f635dd61f60ffec9b4.debug...done.
done.
(gdb) r
Starting program: /usr/bin/systemsettings5 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fe442c3b700 (LWP 22192)]
[New Thread 0x7fe43a2cd700 (LWP 22193)]
[New Thread 0x7fe42f424700 (LWP 22195)]
[New Thread 0x7fe425c3c700 (LWP 22196)]

Thread 1 "systemsettings5" received signal SIGSEGV, Segmentation fault.
0x00007fe4538e8dd8 in KSycocaEntry::name() const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5
(gdb) backtrace 
#0  0x00007fe4538e8dd8 in KSycocaEntry::name() const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5
#1  0x00007fe42fac3d49 in MostUsedModel::data (this=0x555555aef330, index=..., role=0) at ./sidebar/SidebarMode.cpp:181
#2  0x00007fe45049a04b in QModelIndex::data (arole=0, this=0x7fffffffaff0) at /usr/include/x86_64-linux-gnu/qt5/QtCore/qabstractitemmodel.h:432
#3  QQmlDMAbstractItemModelData::value (role=0, this=0x555555e54b80) at util/qqmladaptormodel.cpp:420
#4  QQmlDMCachedModelData::metaCall (this=0x555555e54b80, call=<optimized out>, id=<optimized out>, arguments=0x7fffffffb0a0) at util/qqmladaptormodel.cpp:292
#5  0x00007fe450604446 in QQmlPropertyData::readProperty (property=0x7fffffffb080, target=0x555555e54b80, this=0x555555e4d0a8)
    at ../../include/QtQml/5.9.0/QtQml/private/../../../../../src/qml/qml/qqmlpropertycache_p.h:302
#6  loadProperty (v4=0x555555d49870, object=0x555555e54b80, property=...) at jsruntime/qv4qobjectwrapper.cpp:166
#7  0x00007fe4506054be in QV4::QObjectWrapper::getQmlProperty (this=0x7fe42483d3e8, qmlContext=0x555555e55260, name=0x7fe42483d3e0, revisionMode=QV4::QObjectWrapper::IgnoreRevision, hasProperty=0x0, 
    includeImports=<optimized out>) at jsruntime/qv4qobjectwrapper.cpp:279
#8  0x00007fe45061e558 in QV4::Object::get (hasProperty=0x0, name=<optimized out>, this=<optimized out>) at jsruntime/qv4object_p.h:334
#9  QV4::Runtime::method_getProperty (engine=0x555555d49870, object=..., nameIndex=<optimized out>) at jsruntime/qv4runtime.cpp:713
#10 0x00007fe4381373db in ?? ()
#11 0x0000555555d61112 in ?? ()
#12 0x0000555500000029 in ?? ()
#13 0x0000555555d49750 in ?? ()
#14 0x00007fe400000003 in ?? ()
#15 0x7ff0000000000000 in ?? ()
#16 0x4059000000000000 in ?? ()
#17 0x4055400000000000 in ?? ()
#18 0x00007fe42483d370 in ?? ()
#19 0x00007fffffffb4a0 in ?? ()
#20 0x0000555555d7dbb0 in ?? ()
#21 0x0000555555d49870 in ?? ()
#22 0x00007fe450595787 in QV4::ExecutionContext::simpleCall (this=<optimized out>, scope=..., callData=callData@entry=0x7fe42483d328, function=0x7fe42483d3d8) at jsruntime/qv4context.cpp:355
#23 0x00007fe4506af7f9 in QQmlJavaScriptExpression::evaluate (this=this@entry=0x555555e58ce0, callData=0x7fe42483d328, isUndefined=isUndefined@entry=0x7fffffffb3ef, scope=...) at qml/qqmljavascriptexpression.cpp:222
#24 0x00007fe4506b9a88 in QQmlNonbindingBinding::doUpdate (this=0x555555e58ce0, watcher=..., flags=..., scope=...) at qml/qqmlbinding.cpp:206
#25 0x00007fe4506b6cc3 in QQmlBinding::update (this=0x555555e58ce0, flags=...) at qml/qqmlbinding.cpp:167
#26 0x00007fe4506c24ff in QQmlObjectCreator::finalize (this=0x555555e4dc00, interrupt=...) at qml/qqmlobjectcreator.cpp:1223
#27 0x00007fe450646a1a in QQmlIncubatorPrivate::incubate (this=0x555555e4da60, i=...) at qml/qqmlincubator.cpp:347
#28 0x00007fe4506472b7 in QQmlEnginePrivate::incubate (this=0x555555d48d80, i=..., forContext=forContext@entry=0x555555d7ea10) at qml/qqmlincubator.cpp:92
#29 0x00007fe4506eec6c in QQmlDelegateModelItem::incubateObject (this=this@entry=0x555555e54b80, component=<optimized out>, engine=<optimized out>, context=context@entry=0x555555e4db40, 
    forContext=forContext@entry=0x555555d7ea10) at types/qqmldelegatemodel.cpp:1959
#30 0x00007fe4506f5486 in QQmlDelegateModelPrivate::object (this=this@entry=0x555555d897b0, group=QQmlListCompositor::Default, index=index@entry=1, asynchronous=asynchronous@entry=false)
    at types/qqmldelegatemodel.cpp:995
#31 0x00007fe4506f5735 in QQmlDelegateModel::object (this=<optimized out>, index=1, asynchronous=<optimized out>) at types/qqmldelegatemodel.cpp:1031
#32 0x00007fe450c714a1 in QQuickRepeaterPrivate::requestItems (this=0x555555d891c0) at items/qquickrepeater.cpp:400
#33 0x00007fe450c7182c in QQuickRepeater::regenerate (this=this@entry=0x555555d61280) at items/qquickrepeater.cpp:394
#34 0x00007fe450c732da in QQuickRepeater::modelUpdated (this=0x555555d61280, changeSet=..., reset=<optimized out>) at items/qquickrepeater.cpp:456
#35 0x00007fe450c73530 in QQuickRepeater::qt_static_metacall (_o=_o@entry=0x555555d61280, _c=_c@entry=QMetaObject::InvokeMetaMethod, _id=_id@entry=7, _a=_a@entry=0x7fffffffbc10) at .moc/moc_qquickrepeater_p.cpp:140
#36 0x00007fe450c73ab8 in QQuickRepeater::qt_metacall (this=0x555555d61280, _c=QMetaObject::InvokeMetaMethod, _id=7, _a=0x7fffffffbc10) at .moc/moc_qquickrepeater_p.cpp:260
#37 0x00007fe452815e2c in QMetaObject::activate (sender=sender@entry=0x555555d60460, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=1, argv=argv@entry=0x7fffffffbc10)
    at kernel/qobject.cpp:3781
#38 0x00007fe4528165a7 in QMetaObject::activate (sender=sender@entry=0x555555d60460, m=m@entry=0x7fe4509e74e0 <QQmlInstanceModel::staticMetaObject>, local_signal_index=local_signal_index@entry=1, 
    argv=argv@entry=0x7fffffffbc10) at kernel/qobject.cpp:3628
#39 0x00007fe45070e5e6 in QQmlInstanceModel::modelUpdated (this=this@entry=0x555555d60460, _t1=..., _t2=<optimized out>) at .moc/moc_qqmlobjectmodel_p.cpp:222
#40 0x00007fe4506ed608 in QQmlDelegateModelPrivate::emitModelUpdated (this=<optimized out>, changeSet=..., reset=<optimized out>) at types/qqmldelegatemodel.cpp:1454
#41 0x00007fe4506f2f1f in QQmlDelegateModelGroupPrivate::emitModelUpdated (this=0x555555d89a30, reset=reset@entry=true) at types/qqmldelegatemodel.cpp:2267
#42 0x00007fe4506f30c4 in QQmlDelegateModelPrivate::emitChanges (this=0x555555d897b0) at types/qqmldelegatemodel.cpp:1473
#43 0x00007fe4506f9636 in QQmlDelegateModel::_q_modelReset (this=0x555555d60460) at types/qqmldelegatemodel.cpp:1513
#44 0x00007fe4506f9a25 in QQmlDelegateModel::qt_static_metacall (_o=_o@entry=0x555555d60460, _c=_c@entry=QMetaObject::InvokeMetaMethod, _id=_id@entry=7, _a=_a@entry=0x7fffffffbf10)
    at .moc/moc_qqmldelegatemodel_p.cpp:195
#45 0x00007fe4506f9f58 in QQmlDelegateModel::qt_metacall (this=0x555555d60460, _c=QMetaObject::InvokeMetaMethod, _id=7, _a=0x7fffffffbf10) at .moc/moc_qqmldelegatemodel_p.cpp:336
#46 0x00007fe452815e2c in QMetaObject::activate (sender=sender@entry=0x555555aef330, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=18, argv=argv@entry=0x7fffffffbf10)
    at kernel/qobject.cpp:3781
#47 0x00007fe4528165a7 in QMetaObject::activate (sender=sender@entry=0x555555aef330, m=m@entry=0x7fe452ca7e00 <QAbstractItemModel::staticMetaObject>, local_signal_index=local_signal_index@entry=18, 
    argv=argv@entry=0x7fffffffbf10) at kernel/qobject.cpp:3628
#48 0x00007fe45288d67a in QAbstractItemModel::modelReset (this=this@entry=0x555555aef330, _t1=...) at .moc/moc_qabstractitemmodel.cpp:659
#49 0x00007fe45278b48c in QAbstractItemModel::endResetModel (this=this@entry=0x555555aef330) at itemmodels/qabstractitemmodel.cpp:3230
---Type <return> to continue, or q <return> to quit---
#50 0x00007fe4527b7622 in QSortFilterProxyModel::setSourceModel (this=0x555555aef330, sourceModel=0x555555aef7d0) at itemmodels/qsortfilterproxymodel.cpp:1816
#51 0x00007fe42fac1fa1 in MostUsedModel::setResultModel(KActivities::Stats::ResultModel*)::{lambda()#1}::operator()() const (__closure=<synthetic pointer>) at ./sidebar/SidebarMode.cpp:137
#52 MostUsedModel::setResultModel (model=0x555555db8f70, this=0x555555aef330) at ./sidebar/SidebarMode.cpp:146
#53 SidebarMode::initWidget (this=this@entry=0x555555aeea70) at ./sidebar/SidebarMode.cpp:469
#54 0x00007fe42fac22e9 in SidebarMode::mainWidget (this=0x555555aeea70) at ./sidebar/SidebarMode.cpp:261
#55 0x00005555555624b7 in SettingsBase::changePlugin (this=this@entry=0x555555868480) at ./app/SettingsBase.cpp:328
#56 0x00005555555647e4 in SettingsBase::initApplication (this=<optimized out>) at ./app/SettingsBase.cpp:125
#57 0x00007fe452822286 in QtPrivate::QSlotObjectBase::call (a=0x7fffffffc2e0, r=<optimized out>, this=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qobject_impl.h:101
#58 QSingleShotTimer::timerEvent (this=0x555555a5f6d0) at kernel/qtimer.cpp:318
#59 0x00007fe452816cb3 in QObject::event (this=0x555555a5f6d0, e=<optimized out>) at kernel/qobject.cpp:1268
#60 0x00007fe4543d3a5c in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x555555a5f6d0, e=0x7fffffffc5b0) at kernel/qapplication.cpp:3717
#61 0x00007fe4543db361 in QApplication::notify (this=0x7fffffffc8e0, receiver=0x555555a5f6d0, e=0x7fffffffc5b0) at kernel/qapplication.cpp:3476
#62 0x00007fe4527e8e70 in QCoreApplication::notifyInternal2 (receiver=0x555555a5f6d0, event=event@entry=0x7fffffffc5b0) at kernel/qcoreapplication.cpp:1018
#63 0x00007fe45283d43e in QCoreApplication::sendEvent (event=0x7fffffffc5b0, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:233
#64 QTimerInfoList::activateTimers (this=0x5555557d86c0) at kernel/qtimerinfo_unix.cpp:643
#65 0x00007fe45283dc91 in timerSourceDispatch (source=<optimized out>) at kernel/qeventdispatcher_glib.cpp:182
#66 0x00007fe44bc76587 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#67 0x00007fe44bc767f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#68 0x00007fe44bc7689c in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#69 0x00007fe45283e7cf in QEventDispatcherGlib::processEvents (this=0x5555557e14c0, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#70 0x00007fe4527e706a in QEventLoop::exec (this=this@entry=0x7fffffffc800, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#71 0x00007fe4527efbb4 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1291
#72 0x000055555555fcba in main (argc=<optimized out>, argv=<optimized out>) at ./app/main.cpp:62
(gdb)

Git commit c72349a81b1302f33ffb4c6bb83163f5b2e58d17 by Marco Martin.
Committed on 06/07/2017 at 12:43.
Pushed by mart into branch 'master'.

kservices in MenuItem can be not valid

M  +10   -2    sidebar/SidebarMode.cpp

https://commits.kde.org/systemsettings/c72349a81b1302f33ffb4c6bb83163f5b2e58d17