Server crashes simplifying group by <subquery>

create table t1 (a int) engine=myisam;

insert into t1 values (1),(2);

--echo t1 not const

create table t2 (b int) engine=myisam;

select * from t1, t2 where b in

( select (select a from t1 order by b) as d from t1 group by (select d) );

drop table t1, t2;

/* select#2 */ select (subquery#3) AS d from t1 group by (subquery#4) having <cache>(t1.a) = <ref_null_helper>((subquery#3))

(SUBSELECT_ITEM*)((select `d`))