Query returns wrong type

[systay]

The TPC-H query #7 is returning a different type on Vitess than it does on MySQL.

Error from the vitess-tester run:

for column l_year field types do not match
Not equal: 
MySQL: INT32
Vitess: INT64

The query is:

select supp_nation,
       cust_nation,
       l_year,
       sum(volume) as revenue
from (select n1.n_name                          as supp_nation,
             n2.n_name                          as cust_nation,
             extract(year from l_shipdate)      as l_year,
             l_extendedprice * (1 - l_discount) as volume
      from supplier,
           lineitem,
           orders,
           customer,
           nation n1,
           nation n2
      where s_suppkey = l_suppkey
        and o_orderkey = l_orderkey
        and c_custkey = o_custkey
        and s_nationkey = n1.n_nationkey
        and c_nationkey = n2.n_nationkey
        and (
          (n1.n_name = 'JAPAN' and n2.n_name = 'INDIA')
              or (n1.n_name = 'INDIA' and n2.n_name = 'JAPAN')
          )
        and l_shipdate between '1995-01-01' and '1996-12-31') as shipping
group by supp_nation,
         cust_nation,
         l_year
order by supp_nation,
         cust_nation,
         l_year;