Thread 42 "Thread (pooled)" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7ffed77fe700 (LWP 12342)] std::_Rb_tree_increment (__x=0x52) at /build/gcc/src/gcc/libstdc++-v3/src/c++98/tree.cc:85 85 /build/gcc/src/gcc/libstdc++-v3/src/c++98/tree.cc: No such file or directory. (gdb) bt #0 0x00007ffff3505b60 in std::_Rb_tree_increment(std::_Rb_tree_node_base*) (__x=0x52) at /build/gcc/src/gcc/libstdc++-v3/src/c++98/tree.cc:85 #1 0x00007ffff29751a9 in cv::face::FaceRecognizer::getLabelsByString(cv::String const&) const () at /usr/lib/libopencv_face.so.3.4 #2 0x00007ffff2974faf in cv::face::FaceRecognizer::predict(cv::_InputArray const&, int&, double&) const () at /usr/lib/libopencv_face.so.3.4 #3 0x00007ffff73d0e54 in () at /usr/lib/libdigikamgui.so.5.8.0 #4 0x00007ffff73c7a34 in Digikam::RecognitionDatabase::recognizeFaces(Digikam::ImageListProvider*) () at /usr/lib/libdigikamgui.so.5.8.0 #5 0x00007ffff73c7f00 in Digikam::RecognitionDatabase::recognizeFaces(QList const&) () at /usr/lib/libdigikamgui.so.5.8.0 #6 0x00007ffff777dcf5 in () at /usr/lib/libdigikamgui.so.5.8.0 #7 0x00007ffff778c174 in () at /usr/lib/libdigikamgui.so.5.8.0 #8 0x00007ffff3ebb112 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5 #9 0x00007ffff4c07fec in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5 #10 0x00007ffff4c0f9c6 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5 #11 0x00007ffff3e89da0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5 #12 0x00007ffff3e8ca06 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/libQt5Core.so.5 #13 0x00007ffff3ee6d04 in () at /usr/lib/libQt5Core.so.5 #14 0x00007fffe591ce38 in g_main_context_dispatch () at /usr/lib/libglib-2.0.so.0 #15 0x00007fffe591d081 in () at /usr/lib/libglib-2.0.so.0 #16 0x00007fffe591d10e in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0 #17 0x00007ffff3ee62f1 in QEventDispatcherGlib::processEvents(QFlags to continue, or q to quit--- EventsFlag>) () at /usr/lib/libQt5Core.so.5 #18 0x00007ffff3e883db in QEventLoop::exec(QFlags) () at /usr/lib/libQt5Core.so.5 #19 0x00007ffff63f19d9 in () at /usr/lib/libdigikamcore.so.5.8.0 #20 0x00007ffff3c99b22 in () at /usr/lib/libQt5Core.so.5 #21 0x00007ffff3c9cb4d in () at /usr/lib/libQt5Core.so.5 #22 0x00007fffecfca08c in start_thread () at /usr/lib/libpthread.so.0 #23 0x00007ffff2f88e7f in clone () at /usr/lib/libc.so.6