From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Dunstan <andrew@dunslane.net>
cc: pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Update time zone data files to tzdata release 2024b.
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Wed, 30 Oct 2024 19:07:56 -0400"
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Date: Wed, 30 Oct 2024 19:20:05 -0400
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I wrote:
> So the problem is precisely that *our* interpretation of EST5EDT
> changed when we adopted tzdata 2024b, and that is affecting how
> we dump these old timestamps.  Or at least, that seems like what
> should be happening, but then why is only crake showing a failure?

Oh, got it: of the machines in question, only crake is selecting
EST5EDT as default timezone.  I can see from the buildfarm logs
that drongo and fairywren are using UTC, and as said, my test
instance is selecting America/New_York.  Both UTC and America/New_York
would have rendered these old timestamps the same way all along,
but EST5EDT just changed its interpretation of them.

That means that simply forcing a re-run of the old branches on
crake won't fix it, because pre-v12 branches will still think
that EST5EDT means what it used to.  We need to make sure that
the dumps are taken in a completely stable zone, i.e. UTC.

			regards, tom lane