grOGL1.c: pipehandler() XEvent processing NULL deref

SonarCloud
Access to field 'w_flags' results in a dereference of a null pointer (loaded from variable 'mw')
https://sonarcloud.io/project/issues?open=AZJB16z6NGfDNup0Risq&id=dlmiles_magic

graphics/grOGL1.c

@@ -527,6 +527,8 @@ pipehandler()
 
 	    entry = HashLookOnly(&grOGLWindowTable, (char *)VisEvent->window);
 	    mw = (entry)?(MagWindow *)HashGetValue(entry):0;
+	    if (!mw)
+		break;
 
 	    switch(VisEvent->state)
 	    {