Ok I tried it not sure if the result is different. I also was not able to pass --ignore-plugins to gdb session so it is without the ignoring stuff
#0 0x00007fffed58dd3a in ?? () from /media/DRIVE/opt/calibre-dev/lib/libQt5Widgets.so.5
#1 0x00007fffed5bab41 in QWidget::removeAction(QAction*) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Widgets.so.5
#2 0x00007fffede3d886 in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/site-packages/PyQt5/QtWidgets.so
#3 0x00007ffff7545052 in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#4 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#5 0x00007ffff7543b2d in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#6 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#7 0x00007ffff7543b2d in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#8 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#9 0x00007ffff7543b2d in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#10 0x00007ffff7545353 in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#11 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#12 0x00007ffff74c7cf6 in ?? () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#13 0x00007ffff749c70e in PyObject_Call () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#14 0x00007ffff74aac90 in ?? () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#15 0x00007ffff749c70e in PyObject_Call () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#16 0x00007ffff6379791 in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/lib-dynload/_functools.so
#17 0x00007ffff749c70e in PyObject_Call () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#18 0x00007ffff753efa7 in PyEval_CallObjectWithKeywords () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#19 0x00007fffe7f37325 in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/site-packages/PyQt5/QtCore.so
#20 0x00007fffe7f376b0 in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/site-packages/PyQt5/QtCore.so
#21 0x00007fffe7f31b5b in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/site-packages/PyQt5/QtCore.so
#22 0x00007fffe7f31c2b in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/site-packages/PyQt5/QtCore.so
#23 0x00007fffec833a46 in QObject::event(QEvent*) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Core.so.5
#24 0x00007fffed586b3c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Widgets.so.5
#25 0x00007fffed58a49e in QApplication::notify(QObject*, QEvent*) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Widgets.so.5
#26 0x00007fffede7752e in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/site-packages/PyQt5/QtWidgets.so
#27 0x00007fffec8004e6 in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Core.so.5
#28 0x00007fffec80327a in QCoreApplicationPrivate::sendPostedEvents(QObject* , int, QThreadData*) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Core.so.5
#29 0x00007fffec858443 in ?? () from /media/DRIVE/opt/calibre-dev/lib/libQt5Core.so.5
#30 0x00007fffef567ade in ?? () from /media/DRIVE/opt/calibre-dev/lib/libglib-2.0.so.0
#31 0x00007fffef568910 in g_main_context_dispatch () from /media/DRIVE/opt/calibre-dev/lib/libglib-2.0.so.0
#32 0x00007fffef568af3 in ?? () from /media/DRIVE/opt/calibre-dev/lib/libglib-2.0.so.0
#33 0x00007fffef568bb7 in g_main_context_iteration () from /media/DRIVE/opt/calibre-dev/lib/libglib-2.0.so.0
#34 0x00007fffec85889c in QEventDispatcherGlib:
rocessEvents(QFlags<QEventL oop::ProcessEventsFlag>) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Core.so.5
#35 0x00007fffec7feb9b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsF lag>) () from /media/DRIVE/opt/calibre-dev/lib/libQt5Core.so.5
#36 0x00007fffec8038e5 in QCoreApplication::exec() () from /media/DRIVE/opt/calibre-dev/lib/libQt5Core.so.5
#37 0x00007fffede61edb in ?? () from /media/DRIVE/opt/calibre-dev/lib/python2.7/site-packages/PyQt5/QtWidgets.so
#38 0x00007ffff7545052 in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#39 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#40 0x00007ffff7543b2d in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#41 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#42 0x00007ffff7543b2d in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#43 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#44 0x00007ffff7543b2d in PyEval_EvalFrameEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#45 0x00007ffff7545eb0 in PyEval_EvalCodeEx () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#46 0x00007ffff74c7cf6 in ?? () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#47 0x00007ffff749c70e in PyObject_Call () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#48 0x00007ffff753efa7 in PyEval_CallObjectWithKeywords () from /media/DRIVE/opt/calibre-dev/lib/../lib/libpython2.7.so.1.0
#49 0x00007ffff7bd2569 in execute_python_entrypoint () from /media/DRIVE/opt/calibre-dev/lib/libcalibre-launcher.so
#50 0x0000000000400628 in ?? ()
#51 0x00007ffff78522b1 in __libc_start_main (main=0x4005f0, argc=1, argv=0x7fffffffdf48, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffdf38) at ../csu/libc-start.c:291
#52 0x0000000000400659 in ?? ()
#53 0x00007fffffffdf38 in ?? ()
#54 0x000000000000001c in ?? ()
#55 0x0000000000000001 in ?? ()
#56 0x00007fffffffe284 in ?? ()
#57 0x0000000000000000 in ?? ()