Regression in Postgres 17?

Hi,

This works in Postgres 15:

pg15> create function json_test(out value text, out json jsonb)
returns record
language sql
as
$$
select null::text, null::jsonb;
$$
;
CREATE FUNCTION
pg15> select * from json_test();
┌───────┬──────┐
│ value │ json │
├───────┼──────┤
│ │ │
└───────┴──────┘
(1 row)

In Postgres 17 trying to create the function yields an error:

pg17> create function json_test(out value text, out json jsonb)
returns record
language sql
as
$$
select null::text, null::jsonb;
$$
;
ERROR: syntax error at or near "jsonb"
LINE 1: create function json_test(out value text, out json jsonb)

Am I doing something wrong? Or is this a regression?

Thanks,

Colin