Submitted by: @asfernandes

Is related to QA556

Test case:

create domain d1 integer not null;
select cast(null as d1) from rdb$database; -- error: ok

    CAST 

============
Statement failed, SQLSTATE = 42000
validation error for CAST, value "*** null ***"

create view v1 as select cast(null as d1) x from rdb$database;
select * from v1; -- returns null: not ok

       X 

============
<null>

Commits: e65fd8f