Prefer the dedecated conversion function

enum.c

@@ -1224,7 +1224,7 @@ enum_tally(int argc, VALUE *argv, VALUE obj)
 {
     VALUE hash;
     if (rb_check_arity(argc, 0, 1)) {
-        hash = rb_convert_type(argv[0], T_HASH, "Hash", "to_hash");
+        hash = rb_to_hash_type(argv[0]);
         rb_check_frozen(hash);
     }
     else {