If you can reproduce the crash at will (or you experience this regularly), can you install the "kdegraphics-dbg" package and post a complete backtrace here? Thanks

Hi again!

In order to be sure that the problem is with my machine, on another computer I set up a virtual machine, set up debian testing, all up-to-date, installed the kdegraphics-dbg you told me, installed also gdb, and reproduced the problem as always. 

exact reproduction actions:
Open a folder with jpgs, open a jpg, rotate it, skip 2-3 jpgs, rotate another, skip 2-3 jpg, rotate another, repeat process until you rotate about 10-12 jpgs, then click save-all, and there's always the crash.

Application: Gwenview (gwenview), signal SIGSEGV
[Current thread is 0 (LWP 2410)]

Thread 3 (Thread 0xb46bab90 (LWP 2412)):
#0  0xb8063416 in __kernel_vsyscall ()
#1  0xb6043f65 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/i686/cmov/libpthread.so.0
#2  0xb693785d in pthread_cond_wait () from /lib/i686/cmov/libc.so.6
#3  0xb7aca502 in QWaitCondition::wait (this=0x82c5e98, mutex=0x82c5e94, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#4  0xb7fba09f in Gwenview::SemanticInfoThread::run (this=0x82c5e88) at ../../../gwenview/lib/semanticinfo/nepomuksemanticinfobackend.cpp:135
#5  0xb7ac9522 in QThreadPrivate::start (arg=0x82c5e88) at thread/qthread_unix.cpp:188
#6  0xb60404b5 in start_thread () from /lib/i686/cmov/libpthread.so.0
#7  0xb6928a5e in clone () from /lib/i686/cmov/libc.so.6

Thread 2 (Thread 0xb3866b90 (LWP 2414)):
#0  0xb8063416 in __kernel_vsyscall ()
#1  0xb6044292 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/i686/cmov/libpthread.so.0
#2  0xb69378b4 in pthread_cond_timedwait () from /lib/i686/cmov/libc.so.6
#3  0xb7aca4dc in QWaitCondition::wait (this=0x850f280, mutex=0x850f27c, time=30000) at thread/qwaitcondition_unix.cpp:85
#4  0xb7abfcfe in QThreadPoolThread::run (this=0x850f4f8) at concurrent/qthreadpool.cpp:140
#5  0xb7ac9522 in QThreadPrivate::start (arg=0x850f4f8) at thread/qthread_unix.cpp:188
#6  0xb60404b5 in start_thread () from /lib/i686/cmov/libpthread.so.0
#7  0xb6928a5e in clone () from /lib/i686/cmov/libc.so.6

Thread 1 (Thread 0xb5c3f710 (LWP 2410)):
[KCrash Handler]
#6  QUrlPrivate::parse (this=0x86a4518, parseOptions=QUrlPrivate::ParseAndSet) at io/qurl.cpp:3584
#7  0xb7b7acb0 in QUrl::isValid (this=0x84df844) at io/qurl.cpp:3961
#8  0xb7f91048 in Gwenview::SortedDirModel::indexForUrl (this=0x82af550, url=@0x84df844) at ../../../gwenview/lib/semanticinfo/sorteddirmodel.cpp:152
#9  0x0807edab in Gwenview::MainWindow::generateThumbnailForUrl (this=0x8289ab0, url=@0x84df844) at ../../../gwenview/app/mainwindow.cpp:1153
#10 0x080841c9 in Gwenview::MainWindow::qt_metacall (this=0x8289ab0, _c=QMetaObject::InvokeMetaMethod, _id=30, _a=0xbfb9a42c) at ./mainwindow.moc:154
#11 0xb7bcfad3 in QMetaObject::activate (sender=0xb7fcf7a8, from_signal_index=5, to_signal_index=5, argv=0xbfb9a42c) at kernel/qobject.cpp:3112
#12 0xb7bd0722 in QMetaObject::activate (sender=0xb7fcf7a8, m=0xb7fcb628, local_signal_index=1, argv=0xbfb9a42c) at kernel/qobject.cpp:3186
#13 0xb7f62393 in Gwenview::DocumentFactory::documentChanged (this=0xb7fcf7a8, _t1=@0x84df844) at ./documentfactory.moc:97
#14 0xb7f62c75 in Gwenview::DocumentFactory::slotSaved (this=0xb7fcf7a8, url=@0x84df844) at ../../../gwenview/lib/document/documentfactory.cpp:200
#15 0xb7f62d2a in Gwenview::DocumentFactory::qt_metacall (this=0xb7fcf7a8, _c=QMetaObject::InvokeMetaMethod, _id=3, _a=0xbfb9a54c) at ./documentfactory.moc:78
#16 0xb7bcfad3 in QMetaObject::activate (sender=0x85055d8, from_signal_index=10, to_signal_index=10, argv=0xbfb9a54c) at kernel/qobject.cpp:3112
#17 0xb7bd0722 in QMetaObject::activate (sender=0x85055d8, m=0xb7fcb5ac, local_signal_index=6, argv=0xbfb9a54c) at kernel/qobject.cpp:3186
#18 0xb7f608f3 in Gwenview::Document::saved (this=0x85055d8, _t1=@0x84df844) at ./document.moc:156
#19 0xb7f6094a in Gwenview::Document::slotCleanChanged (this=0x0, clean=true) at ../../../gwenview/lib/document/document.cpp:392
#20 0xb7f60cf5 in Gwenview::Document::qt_metacall (this=0x85055d8, _c=QMetaObject::InvokeMetaMethod, _id=13, _a=0x85231f8) at ./document.moc:103
#21 0xb7bc92db in QMetaCallEvent::placeMetaCall (this=0x86e74f0, object=0x85055d8) at kernel/qobject.cpp:477
#22 0xb7bcadb0 in QObject::event (this=0x85055d8, e=0x86e74f0) at kernel/qobject.cpp:1110
#23 0xb6bd87d4 in QApplicationPrivate::notify_helper (this=0x8235650, receiver=0x85055d8, e=0x86e74f0) at kernel/qapplication.cpp:4056
#24 0xb6be093e in QApplication::notify (this=0xbfb9ac80, receiver=0x85055d8, e=0x86e74f0) at kernel/qapplication.cpp:3603
#25 0xb78495ed in KApplication::notify (this=0xbfb9ac80, receiver=0x85055d8, event=0x86e74f0) at ../../kdeui/kernel/kapplication.cpp:307
#26 0xb7bba96b in QCoreApplication::notifyInternal (this=0xbfb9ac80, receiver=0x85055d8, event=0x86e74f0) at kernel/qcoreapplication.cpp:610
#27 0xb7bbb5ae in QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x821fd10) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#28 0xb7bbb78d in QCoreApplication::sendPostedEvents (receiver=0x0, event_type=0) at kernel/qcoreapplication.cpp:1140
#29 0xb7be5baf in postEventSourceDispatch (s=0x8237910) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#30 0xb608c368 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#31 0xb608f8c3 in ?? () from /usr/lib/libglib-2.0.so.0
#32 0x08237890 in ?? ()
#33 0x00000000 in ?? ()

This is bug 189992, already fixed.
Thanks

*** This bug has been marked as a duplicate of bug 189992 ***