mruby-test-inline-struct/inline.c: add a comment about istruct protection.
@@ -59,6 +59,9 @@ istruct_test_test_receive_direct(mrb_state *mrb, mrb_value self)
mrb_value is;
struct RClass *klass = mrb_class_get(mrb, "InlineStructTest");
mrb_get_args(mrb, "o", &is);
+ /* if you need to protect istruct retrieval from untrusted code,
+ you need to care about class replacing.
+ See mrbgem/mruby-random/src/random.c for detail */
if (mrb_istruct_p(is) && mrb_obj_is_kind_of(mrb, is, klass)) {
char *ptr = mrb_istruct_ptr(is);;
return mrb_bool_value(ptr[0] == 's');
