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From: Erik Cederstrand <erik@cederstrand.dk>
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Date: Sun, 14 Nov 2010 21:57:25 +0100
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To: Dimitry Andric <dim@FreeBSD.org>
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Subject: Re: Deterministic builds?
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Den 14/11/2010 kl. 21.32 skrev Dimitry Andric:

> On 2010-11-14 21:22, Erik Cederstrand wrote:
>> I'm curious as to why this might be useful? Would the mtime of the
>> file not be be sufficient? I can only think of debugging purposes, =
but
>> apart from the timestamp, two kernels with the same rev. would be
>> bitwise identical,
>=20
> This does not have to be the case.  For example, if you have have =
local
> modifications, or use different settings in make.conf or src.conf.

In this case the timestamp + rev. is not sufficient to reproduce the =
kernel anyway. You'd need to store externally the non-standard contents =
of conf files, local diffs etc. on all your non-standard builds. You =
could do all sorts of fun stuff, even fool the rev. number or timestamp =
if you wanted.

I'm just saying that for the standard user on a standard GENERIC kernel =
(and world for that matter) - the revision number should be sufficient =
for e.g. filing a PR. If you need the timestamp, there's the mtime.

Erik=

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