Core was generated by `ubuntu-download-manager/ubuntu-download-manager -self-signed-certs /home/barry/'.
Program terminated with signal 11, Segmentation fault.
#0  0x00007fdfdfb75be4 in Download::state() ()
   from libubuntudownloadmanager/libubuntudownloadmanager.so.1
(gdb) where
#0  0x00007fdfdfb75be4 in Download::state() ()
   from libubuntudownloadmanager/libubuntudownloadmanager.so.1
#1  0x00007fdfdfb8a201 in GroupDownloadPrivate::cancelDownload() ()
   from libubuntudownloadmanager/libubuntudownloadmanager.so.1
#2  0x00007fdfdfb82472 in DownloadQueue::qt_static_metacall(QObject*, QMetaObject::Call, int, void**) ()
   from libubuntudownloadmanager/libubuntudownloadmanager.so.1
#3  0x00007fdfdf76f066 in QMetaObject::activate(QObject*, int, int, void**) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fdfdfb76345 in Download::qt_static_metacall(QObject*, QMetaObject::Call, int, void**) () from libubuntudownloadmanager/libubuntudownloadmanager.so.1
#5  0x00007fdfdf75398b in QMetaMethod::invoke(QObject*, Qt::ConnectionType, QGenericReturnArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument) const ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fdfdf757128 in QMetaObject::invokeMethod(QObject*, char const*, Qt::ConnectionType, QGenericReturnArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fdfdfb8b6b1 in GroupDownloadAdaptor::cancel() ()
   from libubuntudownloadmanager/libubuntudownloadmanager.so.1
#8  0x00007fdfdfba9fdd in GroupDownloadAdaptor::qt_static_metacall(QObject*, QMetaObject::Call, int, void**) ()
   from libubuntudownloadmanager/libubuntudownloadmanager.so.1
#9  0x00007fdfdfbaa2f3 in GroupDownloadAdaptor::qt_metacall(QMetaObject::Call, int, void**) () from libubuntudownloadmanager/libubuntudownloadmanager.so.1
#10 0x00007fdfde38b0df in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#11 0x00007fdfde38bfe1 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#12 0x00007fdfde38cca3 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#13 0x00007fdfde38cd2e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#14 0x00007fdfdf77006e in QObject::event(QEvent*) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007fdfdf74ae5d in QCoreApplication::notify(QObject*, QEvent*) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007fdfdf74ab8d in QCoreApplication::notifyInternal(QObject*, QEvent*)
    () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007fdfdf74c367 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#18 0x00007fdfdf78fd13 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x00007fdfdcfff446 in g_main_context_dispatch ()
   from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007fdfdcfff798 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007fdfdcfff83c in g_main_context_iteration ()
   from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#22 0x00007fdfdf78f9dc in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#23 0x00007fdfdf749a3b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#24 0x00007fdfdf74f1d1 in QCoreApplication::exec() ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#25 0x0000000000400993 in main ()