From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51554) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e7j6p-0005YK-OL for qemu-devel@nongnu.org; Thu, 26 Oct 2017 10:26:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e7j6l-0007Vx-UO for qemu-devel@nongnu.org; Thu, 26 Oct 2017 10:26:11 -0400 Received: from mail-wm0-x22e.google.com ([2a00:1450:400c:c09::22e]:43868) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1e7j6l-0007VD-Ni for qemu-devel@nongnu.org; Thu, 26 Oct 2017 10:26:07 -0400 Received: by mail-wm0-x22e.google.com with SMTP id m72so19652465wmc.0 for ; Thu, 26 Oct 2017 07:26:07 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20171026100645.GA24581@redhat.com> References: <20171025123056.3165-1-richard.henderson@linaro.org> <20171026070608.GC5847@redhat.com> <20171026100645.GA24581@redhat.com> From: Peter Maydell Date: Thu, 26 Oct 2017 15:25:45 +0100 Message-ID: Content-Type: text/plain; charset="UTF-8" Subject: Re: [Qemu-devel] [PULL 00/11] Disassembler patches List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: Richard Henderson , QEMU Developers On 26 October 2017 at 11:06, Daniel P. Berrange wrote: > Do we really expect make/configure todo the right thing when going > backwards in time ? I've always assumed that if you go back in time > when you need to do a 'git clean -f -x d' and re-run configure from > scratch. Certainly in the past various makefile changes in QEMU would > break, or silently not correctly recompile stuff when going backwards > in time. Yes. Occasionally we accidentally break this, as you note, and then git bisection across that kind of boundary requires a painful build from clean. But almost always bisection (across small spans of history) works without having to do that, as do things like "check out this branch I was working on a month ago and do a build without bothering to clean first". In this case you broke my standard workflow for rolling back from an attempted merge that didn't actually build, which IME is a pretty rare thing to have go wrong. thanks -- PMM