Hard deadlock between ALTER TABLE and INSERT

--source include/have_debug_sync.inc

--source include/have_metadata_lock_info.inc

CREATE TABLE t1(a INT) ENGINE=Aria;

connect con1, localhost, root;

SET debug_sync='thr_multi_lock_before_thr_lock SIGNAL ready WAIT_FOR go';

send INSERT INTO t1 VALUES(1);

connection default;

SET debug_sync='now WAIT_FOR ready';

SET debug_sync='alter_table_inplace_before_lock_upgrade SIGNAL go';

ALTER TABLE t1 MODIFY a INT DEFAULT NULL;

connection con1;

reap;

disconnect con1;

DROP TABLE t1;

SET debug_sync='RESET';