diff --git a/library/include/dfhack/modules/World.h b/library/include/dfhack/modules/World.h
index 0985e5cfa..82ecb88b8 100644
--- a/library/include/dfhack/modules/World.h
+++ b/library/include/dfhack/modules/World.h
@@ -31,7 +31,7 @@ namespace DFHack
         GM_Kittens = 2, // not sure yet, but I think it will involve kittens
         GM_Menu = 3,
         GM_Arena = 4,
-        GM_MAX
+        GM_MAX = 4,
     };
     struct t_gamemodes
     {