Re: BUG #18832: Segfault in GrantLockLocal

On Thu, Mar 6, 2025 at 9:57 PM PG Bug reporting form
<noreply(at)postgresql(dot)org> wrote:
> While running some tests on a recent HEAD commit (d4a6c847ca), I got 3
> segfaults today (2 for ALTER DEFAULT PRIVILEGES and 1 FOR SELECT
> pg_drop_replication_slot()). I just happen to be testing this commit, so I
> am not suspecting this commit to be the cause, but what I can add is that
> I've run similar workloads last month and these crashes are too close to be
> a coincidence - in effect I wouldn't be surprised if this is owing to a
> recent change.

I encountered the same issue months ago and reported it here [1].
Heikki suspected that commit 3c0fd64fec might be the culprit.
Unfortunately, we haven't been able to track it down because we
couldn't find a reliable way to reproduce it.

Your report shows that this issue still exists on master. I think it
would be great if we could take this chance to trace it down to the
root cause.

[1] https://www.postgresql.org/message-id/flat/CAMbWs4_dNX1SzBmvFdoY-LxJh_4W_BjtVd5i008ihfU-wFF%3Deg%40mail.gmail.com

Thanks
Richard