Pasting attachment inline:

Application: nepomukservicestub (0.2)
KDE Platform Version: 4.6.5 (4.6.5)
Qt Version: 4.7.2
Operating System: Linux 2.6.38-8-generic x86_64
Distribution: Ubuntu 11.04

-- Information about the crash:
Browsing the Web (YouTube on Firefox). I wasn't using Nepomuk Backup at the moment; no unusual symptoms noticed (was it a real crash?)

-- Backtrace:
Application: Nepomuk Service Stub (nepomukservicestub), signal: Aborted
__lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
	in ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S
[Current thread is 1 (Thread 0x7f9894f61780 (LWP 2229))]

Thread 3 (Thread 0x7f9884116700 (LWP 2239)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f989496482b in wait (this=<value optimized out>, mutex=0x13bc3f0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x13bc3f0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007f988474b41f in Nepomuk::IndexFeeder::run (this=0x13bc3d0) at ../../../../nepomuk/services/strigi/nepomukindexfeeder.cpp:188
#4  0x00007f9894964175 in QThreadPrivate::start (arg=0x13bc3d0) at thread/qthread_unix.cpp:320
#5  0x00007f989232bd8c in start_thread (arg=0x7f9884116700) at pthread_create.c:304
#6  0x00007f989262904d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f9881089700 (LWP 2240)):
[KCrash Handler]
#6  0x00007f9892576d05 in raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#7  0x00007f989257aab6 in abort () at abort.c:92
#8  0x00007f98925afd7b in __libc_message (do_abort=2, fmt=0x7f9892698400 "*** glibc detected *** %s: %s: 0x%s ***\n") at ../sysdeps/unix/sysv/linux/libc_fatal.c:189
#9  0x00007f98925bba8f in malloc_printerr (av=<value optimized out>, p=0x7f987c3477b0) at malloc.c:6283
#10 _int_free (av=<value optimized out>, p=0x7f987c3477b0) at malloc.c:4795
#11 0x00007f98925bf8e3 in __libc_free (mem=<value optimized out>) at malloc.c:3738
#12 0x00007f98949a90fc in QString::free (d=0x7f987c3477c0) at tools/qstring.cpp:1185
#13 0x00007f98949a9672 in QString::operator= (this=<value optimized out>, other=...) at tools/qstring.cpp:1359
#14 0x00007f9894a27f5a in QFSFileEngineIterator::advance (this=0x1462b40) at io/qfsfileengine_iterator_unix.cpp:73
#15 0x00007f9894a20390 in QFSFileEngineIterator::next (this=0x1462b40) at io/qfsfileengine_iterator.cpp:65
#16 0x00007f98949df2e4 in QDirIteratorPrivate::advance (this=0x14465e0) at io/qdiriterator.cpp:217
#17 0x00007f98949df48d in QDirIterator::next (this=0x7f9881088bc0) at io/qdiriterator.cpp:457
#18 0x00007f9884741daa in Nepomuk::IndexScheduler::analyzeDir (this=0x1329ff0, dir_=<value optimized out>, flags=...) at ../../../../nepomuk/services/strigi/indexscheduler.cpp:391
#19 0x00007f98847426ec in Nepomuk::IndexScheduler::run (this=0x1329ff0) at ../../../../nepomuk/services/strigi/indexscheduler.cpp:338
#20 0x00007f9894964175 in QThreadPrivate::start (arg=0x1329ff0) at thread/qthread_unix.cpp:320
#21 0x00007f989232bd8c in start_thread (arg=0x7f9881089700) at pthread_create.c:304
#22 0x00007f989262904d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#23 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f9894f61780 (LWP 2229)):
#0  __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
#1  0x00007f98925c180f in _L_lock_12013 () from /lib/x86_64-linux-gnu/libc.so.6
#2  0x00007f98925bf8d8 in __libc_free (mem=0x7f987c000020) at malloc.c:3736
#3  0x00007f98949a90fc in QString::free (d=0x7f987c1dd3c0) at tools/qstring.cpp:1185
#4  0x00007f989469ac2d in ~QString (this=0x12c7a20, object=0x13a7de0, flags=337, msg=...) at ../../include/QtCore/../../src/corelib/tools/qstring.h:883
#5  QDBusConnectionPrivate::activateCall (this=0x12c7a20, object=0x13a7de0, flags=337, msg=...) at qdbusintegrator.cpp:803
#6  0x00007f989469b33a in QDBusConnectionPrivate::activateObject (this=0x12c7a20, node=..., msg=..., pathStartPos=<value optimized out>) at qdbusintegrator.cpp:1410
#7  0x00007f989469b578 in QDBusActivateObjectEvent::placeMetaCall (this=0x7f987c333670) at qdbusintegrator.cpp:1524
#8  0x00007f9894a5f49a in QObject::event (this=0x1344950, e=<value optimized out>) at kernel/qobject.cpp:1226
#9  0x00007f9892d969f4 in QApplicationPrivate::notify_helper (this=0x1232cc0, receiver=0x1344950, e=0x7f987c333670) at kernel/qapplication.cpp:4462
#10 0x00007f9892d9b3ba in QApplication::notify (this=<value optimized out>, receiver=0x1344950, e=0x7f987c333670) at kernel/qapplication.cpp:4341
#11 0x00007f9893d896c6 in KApplication::notify (this=0x7fffef4b7e90, receiver=0x1344950, event=0x7f987c333670) at ../../kdeui/kernel/kapplication.cpp:311
#12 0x00007f9894a4b49c in QCoreApplication::notifyInternal (this=0x7fffef4b7e90, receiver=0x1344950, event=0x7f987c333670) at kernel/qcoreapplication.cpp:731
#13 0x00007f9894a4ec25 in sendEvent (receiver=0x0, event_type=0, data=0x11ef8a0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#14 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x11ef8a0) at kernel/qcoreapplication.cpp:1372
#15 0x00007f9894a76253 in sendPostedEvents (s=0x1236160) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:220
#16 postEventSourceDispatch (s=0x1236160) at kernel/qeventdispatcher_glib.cpp:277
#17 0x00007f989184fbcd in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#18 0x00007f98918503a8 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007f9891850639 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007f9894a763ef in QEventDispatcherGlib::processEvents (this=0x11ef4a0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:422
#21 0x00007f9892e404de in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#22 0x00007f9894a4a882 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#23 0x00007f9894a4aabc in QEventLoop::exec (this=0x7fffef4b7ca0, flags=...) at kernel/qeventloop.cpp:201
#24 0x00007f9894a4eecb in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1008
#25 0x0000000000403d0f in main (argc=2, argv=<value optimized out>) at ../../../nepomuk/servicestub/main.cpp:167

Report to https://bugs.kde.org

*** This bug has been marked as a duplicate of bug 291083 ***