Should raise RuntimeError when object frozen
MODIFY
src/array.c
src/array.c
@@ -796,6 +796,7 @@ mrb_ary_aset(mrb_state *mrb, mrb_value self)
mrb_value v1, v2, v3;
mrb_int i, len;
+ mrb_ary_modify(mrb, mrb_ary_ptr(self));
if (mrb_get_args(mrb, "oo|o", &v1, &v2, &v3) == 2) {
switch (mrb_type(v1)) {
/* a[n..m] = v */

Should raise RuntimeError when object frozen