From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27423 invoked by alias); 28 Nov 2007 13:59:47 -0000 Received: (qmail 27409 invoked by uid 22791); 28 Nov 2007 13:59:46 -0000 X-Spam-Check-By: sourceware.org Received: from mail5.primus.ca (HELO mail-07.primus.ca) (216.254.141.172) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 28 Nov 2007 13:59:24 +0000 Received: from ottawa-hs-209-217-122-41.s-ip.magma.ca ([209.217.122.41] helo=[192.168.8.125]) by mail-07.primus.ca with esmtpa (Exim 4.63) (envelope-from ) id 1IxNRg-0002wf-0R; Wed, 28 Nov 2007 08:59:20 -0500 Message-ID: <474D7465.1040603@ellipticsemi.com> Date: Wed, 28 Nov 2007 14:35:00 -0000 From: Tom St Denis User-Agent: Thunderbird 2.0.0.6 (X11/20071022) MIME-Version: 1.0 To: Duft Markus CC: Fabian Cenedese , gcc-help@gcc.gnu.org Subject: Re: reduce compilation times? References: <18597F2B47F1394A9B309945EC72411201344D6A@servex01.wamas.com> In-Reply-To: <18597F2B47F1394A9B309945EC72411201344D6A@servex01.wamas.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated: elp125 - ottawa-hs-209-217-122-41.s-ip.magma.ca ([192.168.8.125]) [209.217.122.41] X-IsSubscribed: yes Mailing-List: contact gcc-help-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-help-owner@gcc.gnu.org X-SW-Source: 2007-11/txt/msg00371.txt.bz2 Duft Markus wrote: > You didn't get the question: i was asking if a *change* in a header is > recognized to affect a *certain* .cpp file, not how make handles > dependencies and updates targets. Micorosft recognizes that a change in > a certain struct inside a header file may not require a recompilation of > a certain .cpp file if it doesn't use that struct. Thats what i asked > for. > Sounds like a nice feature, but honestly, I'm a bit paranoid, most of the time when I edit header files I just do a "make clean" first anyways. In a lot of our smaller SDKs, we often do a clean as part of the "code/test/verify" cycle. It's just simpler to make sure everything is fresh then have some lingering files that weren't picked up properly in a makefile. On the larger projects we only clean if the headers change for obvious reasons. But I can't say honestly that I spend more time editing header files than source files. Tom