Re: Buildfarm failure and dubious coding in predicate.c

On Tue, Jul 25, 2017 at 7:24 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Thomas Munro <thomas(dot)munro(at)enterprisedb(dot)com> writes:
>> Ahh, I think I see it. This is an EXEC_BACKEND build farm animal.
>> Theory: After the backend we see had removed the scratch entry and
>> before it had restored it, another backend started up and ran
>> InitPredicateLocks(), which inserted a new scratch entry without
>> interlocking.
>
> Ouch. Yes, I think you're probably right. It needs to skip that if
> IsUnderPostmaster. Seems like there ought to be an Assert(!found)
> there, too. And I don't think I entirely like the fact that there's
> no assertions about the found/not found cases below, either.
>
> Will fix, unless you're already on it?

I was going to send a short patch that would test IsUnderPostmaster,
but I got lost down a rabbit hole trying to figure out how to make my
EXEC_BACKEND builds run on this machine... Please go ahead.

--
Thomas Munro
http://www.enterprisedb.com