Re: Instability of phycodorus in pg_upgrade tests with JIT

Andres Freund <andres@anarazel.de> writes:
> On 2025-10-15 19:39:03 -0400, Tom Lane wrote:
>> phycodorus seems to be running a remarkably ancient LLVM version.

> It intentionally tests the oldest supported version... If we don't care, I'm
> happy enough to just remove the animal.

Sure, we'd need to change our docs about the oldest supported LLVM
version if we go that way.

>> I wonder if we should just write these off as "probably an LLVM bug".

> I'm not sure that's really convincing, given that REL_16_STABLE seems to not
> have an issue?

The other side of that coin is that no other LLVM-using animal is
showing similar instability.  Sure, it's plausible that we changed
something in v15 or so that stopped the problem, but is it worth the
effort to try to find out what?  And if we did find it, would we
care to risk back-porting it?

(If you want to research this, I'm not standing in the way.
But I think there are better uses for your time.)

            regards, tom lane