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=-4.2 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD 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 DB1E820373 for ; Mon, 13 Mar 2017 21:00:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751720AbdCMVA2 (ORCPT ); Mon, 13 Mar 2017 17:00:28 -0400 Received: from cloud.peff.net ([104.130.231.41]:43577 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750871AbdCMVA1 (ORCPT ); Mon, 13 Mar 2017 17:00:27 -0400 Received: (qmail 4993 invoked by uid 109); 13 Mar 2017 21:00:26 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.84) with SMTP; Mon, 13 Mar 2017 21:00:26 +0000 Received: (qmail 23513 invoked by uid 111); 13 Mar 2017 21:00:36 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.84) with SMTP; Mon, 13 Mar 2017 17:00:36 -0400 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Mon, 13 Mar 2017 17:00:23 -0400 Date: Mon, 13 Mar 2017 17:00:23 -0400 From: Jeff King To: Marc Stevens Cc: Linus Torvalds , Dan Shumow , Junio C Hamano , Git Mailing List Subject: Re: [PATCH] Put sha1dc on a diet Message-ID: <20170313210023.bumtp6wyw6blmymp@sigill.intra.peff.net> References: <20170301195302.3pybakmjqztosohj@sigill.intra.peff.net> <20170313151322.ouryghyb5orkpk5g@sigill.intra.peff.net> <20170313194848.2z2dlgpomu6e3dkh@sigill.intra.peff.net> <1e6a592f-7da1-8043-0b29-0bb7c8cda3f3@cwi.nl> <161775901.3349663.1489438074825.JavaMail.zimbra@cwi.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <161775901.3349663.1489438074825.JavaMail.zimbra@cwi.nl> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Mon, Mar 13, 2017 at 09:47:54PM +0100, Marc Stevens wrote: > Linus: > I would be surprised, the dependencies should be automatically determined. > > BTW Did you make local changes to this perf branch? I can reproduce it with: cd sha1collisiondetection git clean -dqfx ;# make sure we are starting from scratch git checkout 9c8e73cadb35776d3310e3f8ceda7183fa75a39f make bin/sha1dcsum $file git checkout 55d1db0980501e582f6cd103a04f493995b1df78 make bin/sha1dcsum $file The final call to sha1dcsum will report a collision, even though the first one did not. It also reproduces with the original snippet I posted. I didn't notice because I was just collecting the timings then (and I originally noticed the problem on the versions I had pulled into Git, where it works as expected; but then I am just pulling in the two source files, without all of the libtool magic). -Peff