diff --git a/src/lua.h b/src/lua.h
index 352d29f3..3d527401 100644
--- a/src/lua.h
+++ b/src/lua.h
@@ -39,7 +39,8 @@
 #define lua_upvalueindex(i)	(LUA_GLOBALSINDEX-(i))
 
 
-/* thread status; 0 is OK */
+/* thread status */
+#define LUA_OK		0
 #define LUA_YIELD	1
 #define LUA_ERRRUN	2
 #define LUA_ERRSYNTAX	3