Re: [PATCH 1/3] t5318: demonstrate commit-graph generation v2 corruption

From: Taylor Blau <me@ttaylorr.com>
Date: Jul 15, 2022, 22:05 UTC
Message-ID: <YtHkmb4Qwvo9n00A@nand.local>
In-Reply-To: <10d12d6f-6d86-743f-518b-eb45871509a7@github.com>

On Thu, Jul 14, 2022 at 11:15:42PM -0400, Derrick Stolee wrote:

Show 11 quoted lines

> > +		# This commit will have a date at two seconds past the Epoch,
> > +		# and a (v1) generation number of 1, since it is a root commit.
> > +		#
> > +		# The offset will then be computed as 2-1, which will underflow
>
> I have verified that your test works, but this explanation is confusing me.
> "2 - 1" is 1, which does not underflow. There must be something else going
> on.
>
> Looking ahead, you describe the situation correctly in Patch 3 to show that
> we take "generation - date", so you really just need s/2-1/1-2/ here.

Yes, absolutely. Thanks for catching it.

Junio: you may want to s/2-1/1-2 in this patch's message, or I can send
you a replacement or reroll, whatever is easier.

Thanks, Taylor