Bug #4552

Added extra security for fill faces. This function is being used for
importing now too, and it gets called for quite weird fill cases...
nevertheless, it should not crash!

source/blender/src/editmesh_tools.c

@@ -1167,7 +1167,7 @@ void fill_mesh(void)
 			/* normals default pointing up */
 			efan= addfacelist(efa->v3->tmp.v, efa->v2->tmp.v, 
 							  efa->v1->tmp.v, 0, NULL, NULL);
-			EM_select_face(efan, 1);
+			if(efan) EM_select_face(efan, 1);
 			efa= efa->next;
 		}
 	}