Crash on cursorForPosition on a wrapped line inside QPlainTextEdit.

#include <QApplication>
#include <QPlainTextEdit>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QPlainTextEdit pe;
    pe.setLineWrapMode(QPlainTextEdit::WidgetWidth);
    QTextOption opt = pe.document()->defaultTextOption();
    opt.setFlags(opt.flags() | QTextOption::IncludeTrailingSpaces);
    pe.document()->setDefaultTextOption(opt);
    pe.setPlainText(QString(50, ' ') + QString ("line2"));
    pe.show();

    // manually resize the editor until "line2" is wrapped and click inside the first now wrapped line... BOOM

    return a.exec();
}

#0  0x00007fb4fe377312 in QTextLine::xToCursor(double, QTextLine::CursorPosition) const ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Gui.so.5
#1  0x00007fb4fe3c5c04 in QTextCursorPrivate::movePosition(QTextCursor::MoveOperation, QTextCursor::MoveMode) () from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Gui.so.5
#2  0x00007fb4fe3c65e5 in QTextCursor::movePosition(QTextCursor::MoveOperation, QTextCursor::MoveMode, int) () from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Gui.so.5
#3  0x00007fb4eb9ab6c8 in ?? () from /opt/qtcreator-410b1/lib/qtcreator/plugins/libTextEditor.so
#4  0x00007fb4eb9c878e in TextEditor::TextEditorWidget::keyPressEvent(QKeyEvent*) ()
   from /opt/qtcreator-410b1/lib/qtcreator/plugins/libTextEditor.so
#5  0x00007fb4feaa1db4 in QWidget::event(QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#6  0x00007fb4feb84c0e in QFrame::event(QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#7  0x00007fb4fec083a3 in QAbstractScrollArea::event(QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#8  0x00007fb4fec30075 in QPlainTextEdit::event(QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#9  0x00007fb4fea5c52c in QApplicationPrivate::notify_helper(QObject*, QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#10 0x00007fb4fea63029 in QApplication::notify(QObject*, QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#11 0x00007fb4fd752ae0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Core.so.5
#12 0x00007fb4feabf52b in ?? () from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#13 0x00007fb4fea5c52c in QApplicationPrivate::notify_helper(QObject*, QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#14 0x00007fb4fea63220 in QApplication::notify(QObject*, QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Widgets.so.5
#15 0x00007fb4fd752ae0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Core.so.5
#16 0x00007fb4fe256a58 in QGuiApplicationPrivate::processKeyEvent(QWindowSystemInterfacePrivate::KeyEvent*) () from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Gui.so.5
#17 0x00007fb4fe25b725 in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Gui.so.5
#18 0x00007fb4fe23ce73 in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Gui.so.5
#19 0x00007fb4f4a75080 in ?? ()
   from /opt/qtcreator-410b1/lib/Qt/plugins/platforms/../../lib/libQt5XcbQpa.so.5
#20 0x00007fb4f9099e04 in g_main_dispatch (context=0x7fb4ec001e10)
    at /build/buildd/glib2.0-2.40.2/./glib/gmain.c:3064
#21 g_main_context_dispatch (context=context@entry=0x7fb4ec001e10)
    at /build/buildd/glib2.0-2.40.2/./glib/gmain.c:3663
#22 0x00007fb4f909a048 in g_main_context_iterate (context=context@entry=0x7fb4ec001e10, 
    block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>)
    at /build/buildd/glib2.0-2.40.2/./glib/gmain.c:3734
#23 0x00007fb4f909a0ec in g_main_context_iteration (context=0x7fb4ec001e10, may_block=1)
    at /build/buildd/glib2.0-2.40.2/./glib/gmain.c:3795
#24 0x00007fb4fd7a0047 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Core.so.5
#25 0x00007fb4fd750dca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Core.so.5
#26 0x00007fb4fd758bad in QCoreApplication::exec() ()
   from /opt/qtcreator-410b1/bin/../lib/Qt/lib/libQt5Core.so.5
#27 0x0000000000409731 in ?? ()
#28 0x00007fb4fc3cff45 in __libc_start_main (main=0x406b20, argc=1, argv=0x7ffdc600d8b8, 

import QtQuick 2.7

MouseArea {
    property bool hoversOnCanvas: distance(1.0 - mouseX / width,
                                           mouseY / height,
                                           volatiles.mainAnnotation.center[0],
                                           volatiles.mainAnnotation.center[1])
    // Window width should be so that this line exactly doesn't wrap: ----------------------------------
    onMouseXChanged: console.log('===== mouseX', mouseX, 'hoversOnCanvas', hoversOnCanvas, 'distance', );
}