Submitted by: @dyemanov

Is related to QA25

create table tb1 (id int, col int);
create index tbi1 on tb1 (id);
create index tbi2 on tb1 (col);

insert into tb1 values (1, 1)
insert into tb1 values (2, 2)
insert into tb1 values (1, null)

select *
from tb1 a
left join tb1 b on http://a.id = http://b.id
where a.col is null and a.col+0 is null
--where a.col+0 is null and a.col is null
PLAN JOIN (A NATURAL, B INDEX (TBI1))

select *
from tb1 a
left join tb1 b on http://a.id = http://b.id
--where a.col is null and a.col+0 is null
where a.col+0 is null and a.col is null
PLAN JOIN (A INDEX (TBI2), B INDEX (TBI1))

The bug is inside OPT_compile(), related to handling of missingStack.

Commits: 4bdeba3 c239258