From: http://osdir.com/ml/digikam-users/2014-09/msg00078.html (opened by somebody with the same bug)

I have the problem that digikam crashes when I try to open it at
exactly the moment when the application shall appear on the screen. It
first checks all albums, and then crashes with always the same
segfault report.

Debug information:
$ gdb digikam
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Reading symbols from digikam...(no debugging symbols found)...done.
(gdb) catch throw 
Catchpoint 1 (throw)
(gdb) run
Starting program: /usr/bin/digikam 
warning: Could not load shared library symbols for linux-vdso.so.1.
Do you need "set solib-search-path" or "set sysroot"?
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[New Thread 0x7fffd0900700 (LWP 3266)]
[New Thread 0x7fffc752d700 (LWP 3267)]
[New Thread 0x7fffc6d2c700 (LWP 3268)]
Object::connect: No such signal org::freedesktop::UPower::DeviceAdded(QString)
Object::connect: No such signal org::freedesktop::UPower::DeviceRemoved(QString)
[New Thread 0x7fffc652b700 (LWP 3269)]
QSqlDatabasePrivate::removeDatabase: connection 'ConnectionTest' is still in use, all queries will cease to work.
[Thread 0x7fffc652b700 (LWP 3269) exited]
[New Thread 0x7fffc652b700 (LWP 3270)]

(digikam:3262): GLib-GObject-WARNING **: specified class size for type 'GstBaseAudioSink' is smaller than the parent type's 'GstBaseSink' class size

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_register_static: assertion 'parent_type > 0' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GStreamer-CRITICAL **: gst_element_register: assertion 'g_type_is_a (type, GST_TYPE_ELEMENT)' failed

(digikam:3262): GLib-GObject-WARNING **: specified class size for type 'GstCapsFilter' is smaller than the parent type's 'GstBaseTransform' class size

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GStreamer-CRITICAL **: gst_element_register: assertion 'g_type_is_a (type, GST_TYPE_ELEMENT)' failed

(digikam:3262): GStreamer-CRITICAL **: gst_bin_add: assertion 'GST_IS_ELEMENT (element)' failed

(digikam:3262): GStreamer-CRITICAL **: gst_element_get_static_pad: assertion 'GST_IS_ELEMENT (element)' failed

(digikam:3262): GStreamer-CRITICAL **: gst_object_unref: assertion 'object != NULL' failed

(digikam:3262): GLib-GObject-WARNING **: specified class size for type 'GstBaseAudioSrc' is smaller than the parent type's 'GstPushSrc' class size

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_register_static: assertion 'parent_type > 0' failed

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GStreamer-CRITICAL **: gst_element_register: assertion 'g_type_is_a (type, GST_TYPE_ELEMENT)' failed

(digikam:3262): GLib-GObject-WARNING **: specified class size for type 'GstAlsaSrc' is smaller than the parent type's 'GstAudioSrc' class size

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GStreamer-CRITICAL **: gst_element_register: assertion 'g_type_is_a (type, GST_TYPE_ELEMENT)' failed

(digikam:3262): GLib-GObject-WARNING **: specified class size for type 'GstOss4Sink' is smaller than the parent type's 'GstAudioSink' class size

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GStreamer-CRITICAL **: gst_element_register: assertion 'g_type_is_a (type, GST_TYPE_ELEMENT)' failed

(digikam:3262): GLib-GObject-WARNING **: specified class size for type 'GstOssSrc' is smaller than the parent type's 'GstAudioSrc' class size

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed

(digikam:3262): GLib-CRITICAL **: g_once_init_leave: assertion 'result != 0' failed

(digikam:3262): GStreamer-CRITICAL **: gst_element_register: assertion 'g_type_is_a (type, GST_TYPE_ELEMENT)' failed

Program received signal SIGSEGV, Segmentation fault.
0x00007fffb333ca3e in ?? () from /usr/lib/gstreamer-0.10/libgstautodetect.so
(gdb) bt
#0  0x00007fffb333ca3e in ?? ()
   from /usr/lib/gstreamer-0.10/libgstautodetect.so
#1  0x00007fffde7dcc92 in gst_element_change_state ()
   from /usr/lib/libgstreamer-0.10.so.0
#2  0x00007fffde7dd303 in ?? () from /usr/lib/libgstreamer-0.10.so.0
#3  0x00007fffde7cb032 in ?? () from /usr/lib/libgstreamer-0.10.so.0
#4  0x00007fffde7dcc92 in gst_element_change_state ()
   from /usr/lib/libgstreamer-0.10.so.0
#5  0x00007fffde7dd303 in ?? () from /usr/lib/libgstreamer-0.10.so.0
#6  0x00007fffb378bb5b in ?? ()
   from /usr/lib/gstreamer-0.10/libgstgconfelements.so
#7  0x00007fffb3789ee1 in ?? ()
   from /usr/lib/gstreamer-0.10/libgstgconfelements.so
#8  0x00007fffb378a135 in ?? ()
   from /usr/lib/gstreamer-0.10/libgstgconfelements.so
#9  0x00007fffde7dcc92 in gst_element_change_state ()
   from /usr/lib/libgstreamer-0.10.so.0
#10 0x00007fffde7dd303 in ?? () from /usr/lib/libgstreamer-0.10.so.0
#11 0x00007fffc43443f8 in ?? ()
   from /usr/lib/kde4/plugins/phonon_backend/phonon_gstreamer.so
#12 0x00007fffc4345892 in ?? ()
   from /usr/lib/kde4/plugins/phonon_backend/phonon_gstreamer.so
#13 0x00007fffc4345b80 in ?? ()
---Type <return> to continue, or q <return> to quit---q
 from /usr/lib/kde4/plugins/phonon_backend/phononQuit
(gdb) quit

Reproducible: Always

Steps to Reproduce:
1. Start digikam
2.
3.

Actual Results:  
KDE crash report appears

Expected Results:  
digikam should launch