From Wang Rui, "I've found a possible bug in the new SmoothingVisitor implementation

(with a great 'crease angle' feature), which will crash if the normal
array is already set but without BIND_PER_VERTEX. I just believe that
we should reallocate the normal array in these cases, as the old
implementation does.
"

src/osgUtil/SmoothingVisitor.cpp

@@ -620,7 +620,7 @@ static void smooth_new(osg::Geometry& geom, double creaseAngle)
     if (!vertices) return;
 
     osg::Vec3Array* normals = dynamic_cast<osg::Vec3Array*>(geom.getNormalArray());
-    if (!normals)
+    if (!normals || (normals && normals->size() != vertices->size()))
     {
         normals = new osg::Vec3Array(vertices->size());
         geom.setNormalArray(normals);