ERREUR: cache lookup failed for function 0 with PostgreSQL 15 beta 2, no error with PostgreSQL 14.4

Hi,

A DSS developer from my company, Julien Roze, reported me an error I cannot explained. Is it a new behavior or a bug ?

Original query is much more complicated but here is a simplified test case with postgresql 14 and 15 beta 2 on Debian 11, packages from pgdg :

Ver Cluster Port Status Owner Data directory Log file
14 main 5432 online postgres /var/lib/postgresql/14/main /var/log/postgresql/postgresql-14-main.log
15 main 5433 online postgres /var/lib/postgresql/15/main /var/log/postgresql/postgresql-15-main.log

psql -p 5432

select version();
version
-----------------------------------------------------------------------------------------------------------------------------
PostgreSQL 14.4 (Debian 14.4-1.pgdg110+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 10.2.1-6) 10.2.1 20210110, 64-bit
(1 ligne)

with fakedata as (
select 'hello' word
union all
select 'world' word
)
select *
from (
select word, count(*) over (partition by word) nb from fakedata
) t where nb = 1;

word | nb
-------+----
hello | 1
world | 1
(2 lignes)

with fakedata as (
select 'hello' word
union all
select 'world' word
)
select *
from (
select word, count(*) nb from fakedata group by word
) t where nb = 1;

word | nb
-------+----
hello | 1
world | 1
(2 lignes)

psql -p 5433

select version();
version
------------------------------------------------------------------------------------------------------------------------------------
PostgreSQL 15beta2 (Debian 15~beta2-1.pgdg110+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 10.2.1-6) 10.2.1 20210110, 64-bit
(1 ligne)

with fakedata as (
select 'hello' word
union all
select 'world' word
)
select *
from (
select word, count(*) over (partition by word) nb from fakedata
) t where nb = 1;
ERREUR: cache lookup failed for function 0

with fakedata as (
select 'hello' word
union all
select 'world' word
)
select *
from (
select word, count(*) nb from fakedata group by word
) t where nb = 1;

word | nb
-------+----
hello | 1
world | 1
(2 lignes)

Best regards,
Phil