class.c: set `MRB_FL_CLASS_IS_INHERITED` flag for bootstrapped classes.
@@ -1376,6 +1376,7 @@ boot_defclass(mrb_state *mrb, struct RClass *super)
if (super) {
c->super = super;
mrb_field_write_barrier(mrb, (struct RBasic*)c, (struct RBasic*)super);
+ c->flags |= MRB_FL_CLASS_IS_INHERITED;
}
else {
c->super = mrb->object_class;
