Comment 2 for bug 978847

The crash is fixed, but the test suite shows yet another bug:
SET optimizer_switch = 'derived_merge=on';
CREATE TABLE t1 ( a INT, b INT );
INSERT INTO t1 VALUES (2,1),(3,2);
select * from t1;
a b
2 1
3 2
INSERT INTO t1 SELECT * FROM
( SELECT * FROM t1 ) AS alias;
select * from t1;
a b
2 1
3 2
3 2
3 2

i.e. it inserts two times (3,2) and no (2,1).