LP:884175 - Wrong result with aggregate + varchar key

The following query:

SELECT MAX(f2) FROM t1 where f2 = 'abc';

returns rows even though f2 is defined as VARCHAR(1) and does not contain the value 'abc'. If the column does not have an index, no rows are returned.

Explain: Select tables optimized away
select max(`test`.`t1`.`f2`) AS `MAX(f2)` from `test`.`t1` where multiple equal('abc', `test`.`t1`.`f2`)

repeatable in maria-5.2, mysql-5.5

test case:

DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (f1 VARCHAR(1), f2 VARCHAR(1), KEY (f2));
INSERT INTO t1 VALUES ('a','a');

SELECT MAX(f1) FROM t1 where f1 = 'abc';
SELECT MAX(f2) FROM t1 where f2 = 'abc';