From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 74571 invoked by alias); 5 Apr 2019 19:55:41 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 74558 invoked by uid 89); 5 Apr 2019 19:55:41 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-5.1 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.1 spammy=rerun X-HELO: mail-qt1-f174.google.com Received: from mail-qt1-f174.google.com (HELO mail-qt1-f174.google.com) (209.85.160.174) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 05 Apr 2019 19:55:39 +0000 Received: by mail-qt1-f174.google.com with SMTP id v20so8781043qtv.12 for ; Fri, 05 Apr 2019 12:55:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:from:subject:message-id:date:user-agent:mime-version :content-language:content-transfer-encoding; bh=JCGqsNKPUIKeXUgw+x1OSxx5h2uK8CdGsDyj+XdtAk8=; b=Kk05CAIFR4qpnnnGBGqKutZPAY/4FGRLNsd0yihT924275fbXcw0/UaCaZTcrt8+Uk /uJlLgKZR1jueuFCCiO/joSjibQN7u2SiTe0JxboMMcziNNUiIWCEEMRFwqcG9C/Fj+e ETrdj9031ec8twINYlrnftS0VZaPr/knwesaplco+UsZkzuFOUFpq3Kv3jx2LrOQ+8Ha oOwiN9SVTjmUb0AYThIp5FHPw4l020xGLSs/si35qZzVY2gStMcLrIMZldOsGjmFHR2/ fMernhREW0KxsUKtyGmfjTuKqYVFczcV3omhaNS8wfjy6i1K8jJRJ/iThcOAd188uNu1 P2cg== Return-Path: Received: from [192.168.0.41] (75-166-119-163.hlrn.qwest.net. [75.166.119.163]) by smtp.gmail.com with ESMTPSA id b37sm19668648qtb.92.2019.04.05.12.55.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 05 Apr 2019 12:55:37 -0700 (PDT) To: gcc mailing list From: Martin Sebor Subject: is re-running bootstrap after a change safe? Message-ID: <52db8781-a1f8-5fe1-7e05-ba3f984d9825@gmail.com> Date: Fri, 05 Apr 2019 19:55:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2019-04/txt/msg00084.txt.bz2 Is it safe to rerun make bootstrap after changing GCC source? Say if the first bootstrap succeeds and I then change a single GCC .c file and rerun make bootstrap, am I guaranteed to see the same fallout of the change as I would if I did a pristine build in a clean directory? I have been assuming this is safe and so after each tweak to a patch I work on I rerun make bootstrap in the same build directory. It can speed things up quite a bit. But the recent bootstrap breakage (PR 89980) makes me wonder if it is, in fact, safe. I can see the broken bootstrap today in a clean build yet the bootstrap I did just before checking in the change went fine. Martin