From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS3215 2.6.0.0/16 X-Spam-Status: No, score=-3.9 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_PASS,URIBL_CSS, URIBL_CSS_A shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from out1.vger.email (out1.vger.email [IPv6:2620:137:e000::1:20]) by dcvr.yhbt.net (Postfix) with ESMTP id 549BD1F54E for ; Sat, 16 Jul 2022 00:01:31 +0000 (UTC) Authentication-Results: dcvr.yhbt.net; dkim=pass (1024-bit key; unprotected) header.d=pobox.com header.i=@pobox.com header.b="BH39JC4J"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229817AbiGPABY (ORCPT ); Fri, 15 Jul 2022 20:01:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229507AbiGPABW (ORCPT ); Fri, 15 Jul 2022 20:01:22 -0400 Received: from pb-smtp21.pobox.com (pb-smtp21.pobox.com [173.228.157.53]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D583095B3B for ; Fri, 15 Jul 2022 17:01:21 -0700 (PDT) Received: from pb-smtp21.pobox.com (unknown [127.0.0.1]) by pb-smtp21.pobox.com (Postfix) with ESMTP id E94F01AB568; Fri, 15 Jul 2022 20:01:20 -0400 (EDT) (envelope-from junio@pobox.com) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=7fJFfl1sAq2IGcAjBxHREaERrsu1JHreYaopzG 7XYeY=; b=BH39JC4J2VV7yof7DylDLNBsmixhITLRZwzhydgYy/2Gr8GJcIFrzQ 9MA+BRjKNWWp++cb6zNVFKdqR5pykChMdHiY6UNxZnXKaqOh5SPRS4PTyECvoGPY LwaIK213NcqcvrC77Iwa6vwr4+rkGhlxnGv2cLaxm3z8ioQgUOJ5U= Received: from pb-smtp21.sea.icgroup.com (unknown [127.0.0.1]) by pb-smtp21.pobox.com (Postfix) with ESMTP id E18C61AB567; Fri, 15 Jul 2022 20:01:20 -0400 (EDT) (envelope-from junio@pobox.com) Received: from pobox.com (unknown [34.83.92.57]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pb-smtp21.pobox.com (Postfix) with ESMTPSA id 8F7E61AB566; Fri, 15 Jul 2022 20:01:17 -0400 (EDT) (envelope-from junio@pobox.com) From: Junio C Hamano To: Taylor Blau Cc: Derrick Stolee , git@vger.kernel.org, peff@peff.net, ps@pks.im, wfc@wfchandler.org Subject: Re: [PATCH 1/3] t5318: demonstrate commit-graph generation v2 corruption References: <0a49c86037bac200bb23e1abf9f67363e99c4b7c.1657667404.git.me@ttaylorr.com> <10d12d6f-6d86-743f-518b-eb45871509a7@github.com> Date: Fri, 15 Jul 2022 17:01:16 -0700 In-Reply-To: (Taylor Blau's message of "Fri, 15 Jul 2022 18:05:13 -0400") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Pobox-Relay-ID: 6A776242-049A-11ED-958C-CBA7845BAAA9-77302942!pb-smtp21.pobox.com Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Taylor Blau writes: > On Thu, Jul 14, 2022 at 11:15:42PM -0400, Derrick Stolee wrote: >> > + # This commit will have a date at two seconds past the Epoch, >> > + # and a (v1) generation number of 1, since it is a root commit. >> > + # >> > + # The offset will then be computed as 2-1, which will underflow >> >> I have verified that your test works, but this explanation is confusing me. >> "2 - 1" is 1, which does not underflow. There must be something else going >> on. >> >> Looking ahead, you describe the situation correctly in Patch 3 to show that >> we take "generation - date", so you really just need s/2-1/1-2/ here. > > Yes, absolutely. Thanks for catching it. > > Junio: you may want to s/2-1/1-2 in this patch's message, or I can send > you a replacement or reroll, whatever is easier. I've already done "rebase -i" to do so. But for future reference, the easiest for me is if the author said, after saying "Thanks for catching it", "Will reroll after waiting for a bit to see if there are other comments". That way, I only have to edit the latest draft of "What's cooking" report to mark the topic to be expecting a reroll (which will prevent me from merging the topic down to 'next' prematurely by mistake) and forget about it, until I actually see the updated set of patches. It would be even easier if the updated set of patches said which topic it is meant to replace. That way, I can trust other reviewers about the details of the change between iterations and play a patch monkey, when I am short of time. It is more work to (1) look at the message you are responding to and understand what "2 minus 1" vs "1 minus 2" being discussed is about, and (2) go one level up in the thread to find the line in the patch that was being discussed, and (3) run "rebase -i" and change "pick" to "edit" and (4) find the line in the file that was affected by the hunk in question and edit it. The worst part of it is I'd either have to do it right away before I forget, or mark the message unread so that I can revisit it when I have enough time. Either way is fine, but a straight resend with two notices (one that says "will reroll", the other that says "this replaces topic X") is the easiest to handle for me. Thanks.