Wrong result with range access

--source include/have_innodb.inc

CREATE TABLE t (pk int, a int, PRIMARY KEY (pk), KEY(a)) ENGINE=InnoDB;

INSERT INTO t VALUES (1,3),(2,6),(3,9);

SELECT * FROM t WHERE a < 8 OR ( pk BETWEEN 1 AND 5 AND a BETWEEN 7 AND 10 );

# Cleanup

DROP TABLE t;

SELECT * FROM t WHERE a < 8 OR ( pk BETWEEN 1 AND 5 AND a BETWEEN 7 AND 10 );

pk	a

1	3

2	6

EXPLAIN EXTENDED SELECT * FROM t WHERE a < 8 OR ( pk BETWEEN 1 AND 5 AND a BETWEEN 7 AND 10 );

id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra

1	SIMPLE	t	range	PRIMARY,a	a	5	NULL	2	100.00	Using where; Using index

Warnings:

Note	1003	select `test`.`t`.`pk` AS `pk`,`test`.`t`.`a` AS `a` from `test`.`t` where `test`.`t`.`a` < 8 or `test`.`t`.`pk` between 1 and 5 and `test`.`t`.`a` between 7 and 10

pk	a

1	3

2	6

3	9

EXPLAIN EXTENDED SELECT * FROM t WHERE a < 8 OR ( pk BETWEEN 1 AND 5 AND a BETWEEN 7 AND 10 );

id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra

1	SIMPLE	t	range	PRIMARY,a	a	9	NULL	3	100.00	Using where; Using index

Warnings:

Note	1003	select `test`.`t`.`pk` AS `pk`,`test`.`t`.`a` AS `a` from `test`.`t` where `test`.`t`.`a` < 8 or `test`.`t`.`pk` between 1 and 5 and `test`.`t`.`a` between 7 and 10