BUG #6336: SQL stored procedure returing 'int' calling into SRF does not raise error ...

The following bug has been logged on the website:

Bug reference:      6336
Logged by:          James Robinson
Email address:      jlrobins@socialserve.com
PostgreSQL version: 9.1.2
Operating system:   OSX
Description:=20=20=20=20=20=20=20=20

calling into generate_series() within a 'returns int' (singular) SQL stored
function doesn't raise error (plpgsql does):

-- SQL function elides over fact that generate_series() is a SRF
create function foo_sql()
returns int as
$$
  select * from generate_series(1,5)
$$ language sql stable;

select foo_sql();

/*

whoa --- returns, and just one int.
 foo
-----
   1
*/


create function foo_plpgsql()
returns int as
$$
declare
  retvar int;
begin
  retvar :=3D generate_series(1,5);
  return retvar;
end;
$$ language plpgsql stable;

-- properly fails --- ERROR:  query "SELECT generate_series(1,5)" returned
more than one row
select foo_plpgsql();