A wrong result is returned by the query below for the test case of bug #33389 from mysql-test/t/view.test.

To reproduce the problem first execute the following statements:

create table t1 (a int, key(a));
create table t2 (c int);

create view v1 as select a b from t1;
create view v2 as select 1 a from t2, v1 where c in
(select 1 from t1 where b = a);

insert into t1 values (1), (1);
insert into t2 values (1), (1);

Then run the query
select * from v2.

You'll get:

MariaDB [test]> select * from v2;
Empty set (0.00 sec)

The expected result is:
MariaDB [test]> select * from v2;
---

---

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4 rows in set (0.00 sec)