From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH] diff: add a config option to control orderfile Date: Tue, 17 Sep 2013 14:52:45 -0700 Message-ID: References: <20130915080830.GA30465@redhat.com> <20130917164226.GB20672@redhat.com> <20130917172829.GA21121@redhat.com> <20130917201401.GA22000@redhat.com> <20130917201604.GA22008@redhat.com> <20130917201828.GC16860@sigill.intra.peff.net> <20130917203807.GA22059@redhat.com> <20130917205615.GA20178@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Michael S. Tsirkin" , git@vger.kernel.org To: Jeff King X-From: git-owner@vger.kernel.org Tue Sep 17 23:52:59 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1VM3CX-0003GI-SZ for gcvg-git-2@plane.gmane.org; Tue, 17 Sep 2013 23:52:54 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754025Ab3IQVwt (ORCPT ); Tue, 17 Sep 2013 17:52:49 -0400 Received: from b-pb-sasl-quonix.pobox.com ([208.72.237.35]:47209 "EHLO smtp.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753271Ab3IQVws (ORCPT ); Tue, 17 Sep 2013 17:52:48 -0400 Received: from smtp.pobox.com (unknown [127.0.0.1]) by b-sasl-quonix.pobox.com (Postfix) with ESMTP id 49D2D430BE; Tue, 17 Sep 2013 21:52:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=RlO67LBhlBlSM0T3Ab0ekr8vsy0=; b=rZousx LChn7zLXizGwWSmVhtNtJ4eTs0wzzzQcxx6Se5kqK/zENMwGjolWFNXDHqtps3iL EqYgVPJMh91xOtv/EQuXSfSBquU01+QuPtk2wUUQzVMyHOrcM38Oy/4LFvzkGyqX A6bfbKEtSLlKsafJ7ijdL3x9e+ufTPOZEN8VQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; q=dns; s=sasl; b=fTkHWvdtRMrIshCMWln+sOTnTcSZqYVF exYglNLw1JRM3/aX4PULbbHzfW1NgSERgJ/vxJpyHOdJ06d9UDpJNM8/YWkKlZOB uJX5YWn60VuumCZVoFK/hrK+r9q0gCPnJJRRwTraSZat07QbsPZLjT+Ms9PHigrr 8M/QJBTXoW0= Received: from b-pb-sasl-quonix.pobox.com (unknown [127.0.0.1]) by b-sasl-quonix.pobox.com (Postfix) with ESMTP id 3CFD3430BC; Tue, 17 Sep 2013 21:52:48 +0000 (UTC) Received: from pobox.com (unknown [72.14.226.9]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by b-sasl-quonix.pobox.com (Postfix) with ESMTPSA id A25B1430BB; Tue, 17 Sep 2013 21:52:47 +0000 (UTC) In-Reply-To: <20130917205615.GA20178@sigill.intra.peff.net> (Jeff King's message of "Tue, 17 Sep 2013 16:56:16 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.3 (gnu/linux) X-Pobox-Relay-ID: 7D9D7744-1FE3-11E3-BDBD-CA9B8506CD1E-77302942!b-pb-sasl-quonix.pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Jeff King writes: > I am mostly thinking of the problems we had with the "kup" tool, which > expected stability across diffs that would be signed by both kernel.org. > But as far as I know, they do not use patch-id. More details in case you > are curious (including me arguing that we should not care, and it is > kup's problem!) are here: > > http://thread.gmane.org/gmane.comp.version-control.git/192331/focus=192424 > > rerere is mentioned in that thread, but I believe that it does its own > hash, and does not rely on patch-id. It does not. The reason rerere is relevant in that thread but is not directly relevant here is because the thread is about changing the diff algorithm, hence changing the common-sequence matches between preimage and postimage, resulting in a different shape of the conflicted section. The hash rerere does still depends on the patch text, but it is restricted to the conflicted region, so whatever we do in patch-id will not affect it. Also the rerere database is not keyed by pathname (a conflict in _any_ file as long as they have the same ours/theirs conflicted text is recognised as the same conflict we have already seen), so changing the orderfile would not affect it at all.