Options: sporadic crashes on "Apply"

There are sporadic crashes after clicking apply in the options dialog:

0 __GI_raise /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.21.so 55 0x7ffff5136267
1 __GI_abort /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.21.so 89 0x7ffff5137eca
2 __libc_message /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.21.so 175 0x7ffff5179c53
3 malloc_printerr /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.21.so 4965 0x7ffff5181c69
4 _int_free /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.21.so 3834 0x7ffff5181c69
5 _GI__libc_free /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.21.so 2950 0x7ffff518589c
6 ?? 0x7fffdf9b3ea7
7 ?? 0x7fffdf9b2cc3
8 QWidget::event(QEvent *) 0x7ffff70550b8
9 QApplicationPrivate::notify_helper(QObject *, QEvent *) 0x7ffff70144dc
10 QApplication::notify(QObject *, QEvent *) 0x7ffff7019640
11 QCoreApplication::notifyInternal(QObject *, QEvent *) 0x7ffff5e9f6a3
12 QWidgetPrivate::sendPaintEvent(QRegion const&) 0x7ffff704e4d9
13 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704eaef
14 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
15 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f67a
16 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f67a
17 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
18 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
19 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f67a
20 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f67a
21 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f67a
22 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
23 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
24 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f67a
25 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
26 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
27 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
28 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
29 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
30 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
31 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
32 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
33 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f67a
34 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
35 QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704f824
36 QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *) 0x7ffff704e692
37 ?? 0x7ffff70213a3
38 ?? 0x7ffff7021781
39 QWidgetPrivate::syncBackingStore() 0x7ffff7040b8f
40 QWidget::event(QEvent *) 0x7ffff7055180
41 QApplicationPrivate::notify_helper(QObject *, QEvent *) 0x7ffff70144dc
42 QApplication::notify(QObject *, QEvent *) 0x7ffff7019640
43 QCoreApplication::notifyInternal(QObject *, QEvent *) 0x7ffff5e9f6a3
44 QCoreApplicationPrivate::sendPostedEvents(QObject *, int, QThreadData *) 0x7ffff5ea1913
45 ?? 0x7ffff5ef46f3
46 g_main_context_dispatch 0x7ffff40a2c3d
47 ?? 0x7ffff40a2f20
48 g_main_context_iteration 0x7ffff40a2fcc
49 QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) 0x7ffff5ef4ae7
50 QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) 0x7ffff5e9d252
51 QDialog::exec() 0x7ffff7205ddd
52 Core::Internal::SettingsDialog::execDialog settingsdialog.cpp 708 0x7fffdf2d4498
53 Core::Internal::MainWindow::showOptionsDialog mainwindow.cpp 819 0x7fffdf23dcac
54 Core::Internal::MainWindow::qt_static_metacall moc_mainwindow.cpp 162 0x7fffdf40813e
55 QMetaObject::activate(QObject *, int, int, void * *) 0x7ffff5ecd36e
56 QAction::triggered(bool) 0x7ffff700aa42
57 QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<bool>, void, void (QAction:: *)(bool)>::call qobjectdefs_impl.h 501 0x7ffff7899bb2
58 QtPrivate::FunctionPointer<void (QAction:: *)(bool)>::call<QtPrivate::List<bool>, void> qobjectdefs_impl.h 520 0x7ffff7899a7d
59 QtPrivate::QSlotObject<void (QAction:: *)(bool), QtPrivate::List<bool>, void>::impl qobject_impl.h 143 0x7ffff7899903
60 QMetaObject::activate(QObject *, int, int, void * *) 0x7ffff5eccd0a
61 QAction::triggered(bool) 0x7ffff700aa42
62 QAction::activate(QAction::ActionEvent) 0x7ffff700ce78
63 ?? 0x7ffff718673a
64 ?? 0x7ffff718c8b4
65 QMenu::mouseReleaseEvent(QMouseEvent *) 0x7ffff7190a46
66 QWidget::event(QEvent *) 0x7ffff70550b8
67 QMenu::event(QEvent *) 0x7ffff7191463
68 QApplicationPrivate::notify_helper(QObject *, QEvent *) 0x7ffff70144dc
69 QApplication::notify(QObject *, QEvent *) 0x7ffff7019e25
70 QCoreApplication::notifyInternal(QObject *, QEvent *) 0x7ffff5e9f6a3
71 ?? 0x7ffff71900bf
72 QMenu::mouseReleaseEvent(QMouseEvent *) 0x7ffff719081e
73 QWidget::event(QEvent *) 0x7ffff70550b8
74 QMenu::event(QEvent *) 0x7ffff7191463
75 QApplicationPrivate::notify_helper(QObject *, QEvent *) 0x7ffff70144dc
76 QApplication::notify(QObject *, QEvent *) 0x7ffff7019e25
77 QCoreApplication::notifyInternal(QObject *, QEvent *) 0x7ffff5e9f6a3
78 QApplicationPrivate::sendMouseEvent(QWidget *, QMouseEvent *, QWidget *, QWidget *, QWidget * *, QPointer<QWidget>&, bool) 0x7ffff7018ab2
79 ?? 0x7ffff706fb8a
80 ?? 0x7ffff707217b
81 QApplicationPrivate::notify_helper(QObject *, QEvent *) 0x7ffff70144dc
82 QApplication::notify(QObject *, QEvent *) 0x7ffff7019640
83 QCoreApplication::notifyInternal(QObject *, QEvent *) 0x7ffff5e9f6a3
84 QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent *) 0x7ffff679b0ad
85 QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent *) 0x7ffff679ca85
86 QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) 0x7ffff6781c4f
87 ?? 0x7fffee607170
88 g_main_context_dispatch 0x7ffff40a2c3d
89 ?? 0x7ffff40a2f20
90 g_main_context_iteration 0x7ffff40a2fcc
91 QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) 0x7ffff5ef4ae7
92 QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) 0x7ffff5e9d252
93 QCoreApplication::exec() 0x7ffff5ea4d3d
94 main main.cpp 521 0x40e6a7