diff --git a/mrbgems/mruby-struct/src/struct.c b/mrbgems/mruby-struct/src/struct.c
index 909bf597b..e25843741 100644
--- a/mrbgems/mruby-struct/src/struct.c
+++ b/mrbgems/mruby-struct/src/struct.c
@@ -280,10 +280,10 @@ mrb_struct_s_def(mrb_state *mrb, mrb_value klass)
   /* Check for keyword_init option in arguments */
   if (argc > 0 && mrb_hash_p(argv[argc-1])) {
     mrb_value options = argv[argc-1];
-    mrb_sym keyword_init_sym = mrb_intern_lit(mrb, "keyword_init");
+    mrb_value keyword_init_sym = mrb_symbol_value(MRB_SYM(keyword_init));
 
-    if (mrb_hash_key_p(mrb, options, mrb_symbol_value(keyword_init_sym))) {
-      keyword_init_val = mrb_hash_get(mrb, options, mrb_symbol_value(keyword_init_sym));
+    if (mrb_hash_key_p(mrb, options, keyword_init_sym)) {
+      keyword_init_val = mrb_hash_get(mrb, options, keyword_init_sym);
       argc--; /* Don't treat the options hash as a member name */
     }
   }
@@ -316,7 +316,7 @@ mrb_struct_s_def(mrb_state *mrb, mrb_value klass)
   mrb_value st = make_struct(mrb, name, members, mrb_class_ptr(klass));
 
   /* Set keyword_init value on the struct class */
-  mrb_iv_set(mrb, st, mrb_intern_lit(mrb, "@__keyword_init__"), keyword_init_val);
+  mrb_iv_set(mrb, st, MRB_IVSYM(__keyword_init__), keyword_init_val);
 
   if (!mrb_nil_p(b)) {
     mrb_yield_with_class(mrb, b, 1, &st, st, mrb_class_ptr(st));
@@ -381,7 +381,7 @@ mrb_struct_initialize_withKw(mrb_state *mrb, mrb_value hash, mrb_value self)
 
   /* If there are any invalid keys, raise an error with all of them */
   if (RARRAY_LEN(invalid_keys) > 0) {
-    mrb_value keys_str = mrb_funcall(mrb, invalid_keys, "join", 1, mrb_str_new_lit(mrb, ", "));
+    mrb_value keys_str = mrb_funcall_id(mrb, invalid_keys, MRB_SYM(join), 1, mrb_str_new_lit(mrb, ", "));
     mrb_raisef(mrb, E_ARGUMENT_ERROR, "unknown keywords: %S", keys_str);
   }
 
@@ -398,7 +398,7 @@ mrb_struct_initialize(mrb_state *mrb, mrb_value self)
   mrb_get_args(mrb, "*", &argv, &argc);
 
   klass = mrb_obj_value(mrb_obj_class(mrb, self));
-  keyword_init = mrb_iv_get(mrb, klass, mrb_intern_lit(mrb, "@__keyword_init__"));
+  keyword_init = mrb_iv_get(mrb, klass, MRB_IVSYM(__keyword_init__));
 
   if (mrb_test(keyword_init)) { /* keyword_init: true or other truthy value */
     if (argc > 1 || (argc == 1 && !mrb_hash_p(argv[0]))) {