From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.4 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, T_DKIM_INVALID shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 7A8481F404 for ; Wed, 25 Apr 2018 08:48:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751324AbeDYIsp (ORCPT ); Wed, 25 Apr 2018 04:48:45 -0400 Received: from mail-wm0-f45.google.com ([74.125.82.45]:37659 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751278AbeDYIsk (ORCPT ); Wed, 25 Apr 2018 04:48:40 -0400 Received: by mail-wm0-f45.google.com with SMTP id l16so5376226wmh.2 for ; Wed, 25 Apr 2018 01:48:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version; bh=0Ft0iMjbKc3ZjAYvSGjYGcF/EJtaPYiBu9rvDvZIaPw=; b=b2xWSQsnUnXx4oavYcNYoQFqyQ9YFZ0KOw/UfyHLgfYsP1ZuX2C8bri1pZfVZSRYlJ h/7tw4RmGUzcec9zeNN9FwPOLXnIvhW1HpENZDBwiz8z9zhXB+zidS62BZuBabB9dXOy Y5VlOy8M3R+XNwI+0DwxWkUdc2+BwPOIkKTgU2EOr9xpi9FllLv0SbIgzTfSbgmxlByH WbAZILkERm7tdGgOrCC8ZFBe2PAqVu4WPMpMEc6N/sOUx92Z8kgm0wjncAD/s6Id8xLW VBRbdJTkigpfR8f7CUIviX9U2lUbd3eTW2UvekFYs5EoiVG7LGrvKvIX6EH8JcYVTOQV MX2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:references:date :in-reply-to:message-id:user-agent:mime-version; bh=0Ft0iMjbKc3ZjAYvSGjYGcF/EJtaPYiBu9rvDvZIaPw=; b=j18oe6mUUbK0NgzmVTkx+Ym2ieUR/d3p16Cq6frJ5dzW3DXW/Cvuymi+rsraSCb45L J6AfbT+V0sVmOo8SN8NawY4xcREdgeLmfMqDeWGIAcvTLAguLMJCSq4HFxJFemYHYNYB vyEvxFWrIDkUxxLIkeIze3O/PdJdLAM2RBEZU3GjOuY7osWJ1ZUj3FV1nzMy/hkkRM/O Y53rzDpe9id/do1uyz39gF9ZTmpkbTXbEaEg+2biVOkoXGKlOv5UtP9JvX0zcftgO66z GsVzaOPwnM+RMgYy1Q/Gfn9fNl8HEa5LhtFupBeY6Bt6sN0KjkAmy4FeiWZsc0yFloL9 3YlA== X-Gm-Message-State: ALQs6tAEBaqBEPpSKOULrj/voY2r9da84UAkQtVFm0XRogRA0bCVmqAq Fk/uv4Ox2maM0gprnXwnRWU= X-Google-Smtp-Source: AB8JxZphzJWSaokejBB/cuuMbc9BZNSI2jFdkb7LCRIImZ4Rt0DeJQ4Z5XByZc9BGIKGys7+7LoauQ== X-Received: by 10.28.88.195 with SMTP id m186mr15189090wmb.113.1524646118935; Wed, 25 Apr 2018 01:48:38 -0700 (PDT) Received: from localhost (168.50.187.35.bc.googleusercontent.com. [35.187.50.168]) by smtp.gmail.com with ESMTPSA id q188sm16683637wmb.37.2018.04.25.01.48.37 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 25 Apr 2018 01:48:38 -0700 (PDT) From: Junio C Hamano To: "Robin H. Johnson" Cc: Git Mailing List , =?utf-8?B?TWljaGHFgiBHw7Ny?= =?utf-8?B?bnk=?= , Jeff King , Lars Schneider , Marc Branchaud Subject: Re: [RFC PATCH] checkout: Force matching mtime between files References: <20180413170129.15310-1-mgorny@gentoo.org> Date: Wed, 25 Apr 2018 17:48:37 +0900 In-Reply-To: (Robin H. Johnson's message of "Wed, 25 Apr 2018 07:13:38 +0000") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org "Robin H. Johnson" writes: > In the thread from 6 years ago, you asked about tar's behavior for > mtimes. 'tar xf' restores mtimes from the tar archive, so relative > ordering after restore would be the same, and would only rebuild if the > original source happened to be dirty. > > This behavior is already non-deterministic in Git, and would be improved > by the patch. But Git is not an archiver (tar), but is a source code control system, so I do not think we should spend any extra cycles to "improve" its behaviour wrt the relative ordering, at least for the default case. Only those who rely on having build artifact *and* source should pay the runtime (and preferrably also the maintainance) cost. The best approach to do so is to have those people do the "touch" thing in their own post-checkout hook. People who use Git as the source control system won't have to pay runtime cost of doing the touch thing, and we do not have to maintain such a hook script. Only those who use the "feature" would.