crash when grouping by values()

Invalid read of size 1

at: hp_rec_hashnr (hp_hash.c:320)

by: hp_write_key (hp_write.c:351)

by: heap_write (hp_write.c:52)

by: ha_heap::write_row (ha_heap.cc:249)

by: end_write (sql_class.h:4492)

by: evaluate_join_record (sql_select.cc:16478)

by: sub_select (sql_select.cc:16259)

by: do_select (sql_select.cc:15929)

by: JOIN::exec_inner (sql_select.cc:2496)

by: JOIN::exec (sql_select.cc:2255)

by: mysql_select (sql_select.cc:3192)

by: handle_select (sql_select.cc:363)

by: execute_sqlcom_select (sql_parse.cc:5004)

by: mysql_execute_command (sql_parse.cc:2472)

by: mysql_parse (sql_parse.cc:6124)

by: dispatch_command (sql_parse.cc:1266)

by: do_handle_one_connection (sql_connect.cc:1267)

by: handle_one_connection (sql_connect.cc:1181)

by: start_thread (pthread_create.c:309)

by: clone (clone.S:115)

Address 0x1010ebfa8 is not stack'd, malloc'd or (recently) free'd

--source include/have_innodb.inc

set storage_engine=innodb;

drop table if exists y;

create table y select 1 b;

select 1 from y group by values(b);