Re: shm_mq_set_sender() crash

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> Of course, it's also possible that the ParallelWorkerNumber code is
> entirely correct and something overwrote the null bytes that were
> supposed to be found at that location. It would be very useful to see
> (a) the value of ParallelWorkerNumber and (b) the contents of
> vmq->mq_sender, and in particular whether that's actually a valid
> pointer to a PGPROC in the ProcArray. But unless we can reproduce
> this I don't see how to manage that.

Is it worth replacing that Assert with a test-and-elog that would
print those values?

Given that we've seen only one such instance in the buildfarm, this
might've been just a cosmic ray bit-flip. So one part of me says
not to worry too much until we see it again. OTOH, if it is real
but rare, missing an opportunity to diagnose would be bad.

regards, tom lane