Re: BUG #17066: Cache lookup failed when null (unknown) is passed as anycompatiblemultirange

On Wed, Jul 21, 2021 at 12:54 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Alexander Korotkov <aekorotkov@gmail.com> writes:
> > Do I understand correctly that enforce_generic_type_consistency() is
> > called only after check_generic_type_consistency() returned true?
> > If so, that means some of the checks are redundant.  Therefore, we can
> > replace ereport()'s with Assert()'s.
>
> They are not redundant, IIRC.  I forget the exact mechanism for
> reaching them, but it likely has something to do with aggregates
> or variadic functions.

If checks aren't redundant, there should be cases when they don't
pass.  It would be nice to identify these cases and add them to the
regression tests.  I didn't manage to do this yet.

> In any case, apologies for taking so long to get back to this.  Here's
> a proposed patch (based in part on Neil's earlier patch).

Thank you!  I'll review this and come back to you.

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Regards,
Alexander Korotkov