select date::date
from generate_series(format('%s-%s-%s', syear, 6, 1)::date,
                     format('%s-%s-%s', syear + 1, 5, 31)::date,
                     '1 day'::interval) date;

CREATE OR REPLACE FUNCTION myCycle(syear integer)
RETURNS TABLE(sdate date) AS $$
BEGIN
     RETURN QUERY
         select date::date
         from generate_series(format('%s-%s-%s', syear, 6, 1)::date,
                              format('%s-%s-%s', syear + 1, 5, 31)::date,
                              '1 day'::interval) date;
END;
$$ LANGUAGE plpgsql;

select c.sdate, ot.other_fields
from   myCycle(2015) c
inner  join other_table ot
on     c.sdate = ot.date;