From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Michael Paquier <michael@paquier.xyz>,
        Postgres hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: REINDEX INDEX results in a crash for an index of pg_class since
 9.6
In-reply-to: <20190502210253.lt4p46dvllxarajg@alap3.anarazel.de>
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Thu, 02 May 2019 14:02:53 -0700"
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Date: Thu, 02 May 2019 17:12:03 -0400
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Andres Freund <andres@anarazel.de> writes:
> On 2019-05-02 16:54:11 -0400, Tom Lane wrote:
>> How do you feel about the other patch to rejigger the order of operations
>> in CommandCounterIncrement?  I think that's a bug, but it's probably
>> noncritical for most people.  What I'm leaning towards for that one is
>> waiting till after the minor releases, then pushing it to all branches.

> I've not yet have the mental cycles to look more deeply into it. I
> thought your explanation why the current way is wrong made sense, but I
> wanted to look a bit more into how it came to be how it is now.

Well, I wrote that code, and I can say pretty confidently that this
failure mode just didn't occur to me at the time.

> I agree
> that pushing after the minors would make sense, it's too subtle to go
> for it now.

It is subtle, and given that it's been there this long, I don't feel
urgency to fix it Right Now.  I think we're already taking plenty of
risk back-patching the REINDEX patch :-(

			regards, tom lane