updated for version 7.3.820
Problem:    Build errors and warnings when building with small features and
            Lua, Perl or Ruby.
Solution:   Add #ifdefs and UNUSED.
diff --git a/src/if_lua.c b/src/if_lua.c
index ce65fd2..1458593 100644
--- a/src/if_lua.c
+++ b/src/if_lua.c
@@ -845,8 +845,9 @@
 }
 
     static int
-luaV_dict_iter (lua_State *L)
+luaV_dict_iter (lua_State *L UNUSED)
 {
+#ifdef FEAT_EVAL
     hashitem_T *hi = (hashitem_T *) lua_touserdata(L, lua_upvalueindex(2));
     int n = lua_tointeger(L, lua_upvalueindex(3));
     dictitem_T *di;
@@ -860,6 +861,9 @@
     lua_pushinteger(L, n - 1);
     lua_replace(L, lua_upvalueindex(3));
     return 2;
+#else
+    return 0;
+#endif
 }
 
     static int