QTextLine::glyphRuns crashs on windows

I've got the following code (m_layout is a member QTextLayout):

    m_layout.setText(my_string);
    m_layout.beginLayout();
    auto line = m_layout.createLine();
    m_layout.endLayout();
    m_layout.clearLayout();

    QGlyphRun gr;
    auto glr = line.glyphRuns();

The call to glyphRuns crashes with a stack trace that goes into qwindows.dll:     

    qwindowsd.dll!QWindowsFontEngine::getGlyphBearings(unsigned int glyph, double * leftBearing, double * rightBearing)  @ line 632

The same code works on macOS and Linux with both Qt 5.8 and 5.9