CREATE TABLE t (a int PRIMARY KEY, b int) engine = InnoDB STATS_PERSISTENT=0;
CREATE TABLE t2 (a int PRIMARY KEY) engine = InnoDB STATS_PERSISTENT=0;
INSERT INTO t VALUES (10, 10), (20, 20), (30, 30);
INSERT INTO t2 VALUES (10), (20), (30);
BEGIN;
UPDATE t2 SET a = a + 100;
SELECT * FROM t WHERE a = 20 FOR UPDATE;
a	b
20	20
connect con_2,localhost,root,,;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
BEGIN;
SET DEBUG_SYNC = 'lock_trx_handle_wait_before_unlocked_wait_lock_check SIGNAL upd_locked WAIT_FOR upd_cont';
UPDATE t SET b = 100;
connection default;
SET DEBUG_SYNC="now WAIT_FOR upd_locked";
SET DEBUG_SYNC="lock_wait_before_suspend SIGNAL upd_cont";
SELECT * FROM t WHERE a = 10 FOR UPDATE;
connection con_2;
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
disconnect con_2;
connection default;
a	b
10	10
SET DEBUG_SYNC = 'RESET';
DROP TABLE t;
DROP TABLE t2;