Pg17 Crash in Planning (Arrays + Casting + UDF)

Hackers,

This extremely odd case [2] came in via a report using a lot of PostGIS functions, but it can be reconfigured into a pure-PostgreSQL crasher [1].

CREATE TABLE n (i integer);

CREATE OR REPLACE FUNCTION add(integer)
RETURNS integer
AS 'SELECT 2 * $1 + 4 * $1'
LANGUAGE 'sql' IMMUTABLE STRICT PARALLEL SAFE;

SELECT add(array_length(array_agg(i)::numeric[],1)::integer) FROM n;

The stack trace shows it doesn’t get past planning, and in fact it doesn’t care if the table has data in it or not.

ATB,

P

[1] https://trac.osgeo.org/postgis/ticket/5793#comment:8
[2] https://lists.osgeo.org/pipermail/postgis-devel/2024-October/030428.html