New bug

I haven't looked into what's causing it yet but...

postgres=# SELECT res, * FROM (
SELECT 'foo'||i AS test, i AS res
FROM (VALUES (1)) AS x(i)
UNION ALL
SELECT 'foo'||i, i
FROM (VALUES (2)) AS x(i)
) AS x;
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.

TRAP: FailedAssertion("!(child_attr <= new_max_attr)", File: "prepunion.c", Line: 1726)

Works fine on 8.3 so even though that section of code in prepunion.c hasn't
changed:

postgres=# SELECT res, * FROM (SELECT 'foo'||i AS test, i AS res FROM (VALUES (1)) AS x(i) UNION ALL SELECT 'foo'||i, i FROM (VALUES (2)) AS x(i)) AS x ;
res | test | res
-----+------+-----
1 | foo1 | 1
2 | foo2 | 2
(2 rows)

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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