From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?UTF-8?Q?Court=C3=A8s?=)
Subject: bug#26734: Snippets (even empty ones) of tar sources reset the
	timestamps of all files
Date: Thu, 04 May 2017 00:01:21 +0200
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References: <874lx4d6j7.fsf@lassieur.org> <87h913h0rj.fsf@gnu.org>
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	<87r305iphr.fsf@netris.org>
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In-Reply-To: <87r305iphr.fsf@netris.org> (Mark H. Weaver's message of "Wed, 03
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To: Mark H Weaver <mhw@netris.org>
Cc: 26734@debbugs.gnu.org, =?UTF-8?Q?Cl=C3=A9ment?= Lassieur <clement@lassieur.org>

Mark H Weaver <mhw@netris.org> skribis:

> ludo@gnu.org (Ludovic Court=C3=A8s) writes:
>
>> BTW, what timestamps to we put on the modified files?  We want that to
>> be deterministic so we cannot use the build time.  We cannot use a date
>> in the future, either.  We cannot use Jan. 1 1970 either because that
>> means that modified files may now be older than the unmodified files,
>> which may break build systems; for the same reason, we cannot leave the
>> mtime of modified files unchanged.
>>
>> Now that I think about it, it=E2=80=99s not clear to me what can be done=
 without
>> breaking something.
>>
>> Thoughts?
>
> We could set the timestamp of modified files to be 1 second newer than
> the newest file in the original source archive.

Sounds like a good idea.

Thanks,
Ludo=E2=80=99.