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