Hi Ilia,
Tested on master at 0497318e442, with and without v7:
create temp table t (a int, b int);
insert into t
select i, i from generate_series(1, 100000) i;
create index ti on t (((a not in (42, null)) or b = 1));
analyze t;
set enable_seqscan = off;
explain (costs off)
select * from t where (a not in (42, null)) or b = 1;
master: Index Scan using ti on t
v7: Seq Scan on t
Disabled: true
Filter: (b = 1)
Best regards,
Denis Smirnov