fix for debug mode

panda/src/glstuff/glmisc_src.cxx

@@ -88,7 +88,7 @@ void CLP(init_classes)() {
   CLP(ShaderContext)::init_type();
   CLP(TextureContext)::init_type();
   CLP(VertexBufferContext)::init_type();
-
+  CLP(GraphicsBuffer)::init_type();
   PandaSystem *ps = PandaSystem::get_global_ptr();
   ps->add_system(GLSYSTEM_NAME);