From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D74CDC54EE9 for ; Thu, 22 Sep 2022 19:12:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232518AbiIVTMY (ORCPT ); Thu, 22 Sep 2022 15:12:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230484AbiIVTMV (ORCPT ); Thu, 22 Sep 2022 15:12:21 -0400 Received: from cloud.peff.net (cloud.peff.net [104.130.231.41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E1A3106A10 for ; Thu, 22 Sep 2022 12:12:20 -0700 (PDT) Received: (qmail 6941 invoked by uid 109); 22 Sep 2022 19:12:20 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with ESMTP; Thu, 22 Sep 2022 19:12:20 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 4829 invoked by uid 111); 22 Sep 2022 19:12:20 -0000 Received: from coredump.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Thu, 22 Sep 2022 15:12:20 -0400 Authentication-Results: peff.net; auth=none Date: Thu, 22 Sep 2022 15:12:19 -0400 From: Jeff King To: Derrick Stolee Cc: git@vger.kernel.org, Victoria Dye Subject: Re: t9210-scalar.sh fails with SANITIZE=undefined Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Thu, Sep 22, 2022 at 08:35:22AM -0400, Derrick Stolee wrote: > > I didn't dig further. It's obviously new in v2.38.0-rc1, but I'm not > > sure it's a show-stopper. It _might_ have been there all along, and is > > just now surfacing. Or it might be in an existing experimental feature > > that just wasn't exercised enough in the tests. Or if it really is new > > in scalar, then it will only hurt people using scalar, which didn't > > exist before. So I don't think it's a regression in the strictest sense, > > but it might be nice to get a more accurate understanding of the problem > > before the release. > > Interesting find! > > Here are the index-related settings that Scalar sets as of -rc1: > > * core.preloadIndex=true > * index.threads=true > * index.version=4 > > My gut feeling is that index.version=4 might be the culprit. I thought > we tested GIT_TEST_INDEX_VERSION=4 in some CI modes, but apparently we > do not. Do you get the same error in other tests with that environment > variable? Yeah, that seems by far the most likely of those three. And indeed, running with GIT_TEST_INDEX_VERSION=4 causes even t0000 to fail with the same problem. A minimal reproduction in git.git is just: make SANITIZE=undefined git clone . tmp cd tmp rm .git/index export GIT_INDEX_VERSION=4 ../git reset --hard ;# ok, writes v4 index ../git reset --hard ;# fails reading unaligned v4 index So it seems like a problem with the v4 format in general. Which...yikes. -Peff