8.2.0 build fails with Qt 5.15.1

Fedora rawhide just updated from Qt 5.14.2 to 5.15.1 and now the vtk build fails with:

/builddir/build/BUILD/VTK-8.2.0/Rendering/Qt/vtkQtLabelRenderStrategy.cxx: In member function 'virtual void vtkQtLabelRenderStrategy::ComputeLabelBounds(vtkTextProperty*, vtkUnicodeString, double*)':
/builddir/build/BUILD/VTK-8.2.0/Rendering/Qt/vtkQtLabelRenderStrategy.cxx:229:18: error: aggregate 'QPainterPath path' has incomplete type and cannot be defined
  229 |     QPainterPath path;
      |                  ^~~~
/builddir/build/BUILD/VTK-8.2.0/Rendering/Qt/vtkQtLabelRenderStrategy.cxx: In member function 'virtual void vtkQtLabelRenderStrategy::RenderLabel(int*, vtkTextProperty*, vtkUnicodeString, int)':
/builddir/build/BUILD/VTK-8.2.0/Rendering/Qt/vtkQtLabelRenderStrategy.cxx:331:16: error: aggregate 'QPainterPath path' has incomplete type and cannot be defined
  331 |   QPainterPath path;
      |                ^~~~
/builddir/build/BUILD/VTK-8.2.0/Rendering/Qt/vtkQtLabelRenderStrategy.cxx: In member function 'virtual void vtkQtLabelRenderStrategy::RenderLabel(int*, vtkTextProperty*, vtkUnicodeString)':
/builddir/build/BUILD/VTK-8.2.0/Rendering/Qt/vtkQtLabelRenderStrategy.cxx:442:18: error: aggregate 'QPainterPath path' has incomplete type and cannot be defined
  442 |     QPainterPath path;
      |                  ^~~~

Full logs at https://koschei.fedoraproject.org/package/vtk?collection=f34