From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from einhorn.in-berlin.de (einhorn.in-berlin.de [192.109.42.8]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mail.vr.in-berlin.de", Issuer "IN-Berlin Server CA (G2)" (not verified)) by ozlabs.org (Postfix) with ESMTP id 950ADDDE30 for ; Mon, 21 May 2007 04:40:40 +1000 (EST) Message-ID: <4650960E.9010707@s5r6.in-berlin.de> Date: Sun, 20 May 2007 20:40:14 +0200 From: Stefan Richter MIME-Version: 1.0 To: Segher Boessenkool Subject: Re: 2.6.22-rc2 built on ppc References: <20070520112904.GM3253@aragorn.home.lxtec.de> <46506EE0.9000405@s5r6.in-berlin.de> <200705201849.29805.arnd@arndb.de> <8c9e6fe68260187606a8ad7f402a4fd8@kernel.crashing.org> In-Reply-To: <8c9e6fe68260187606a8ad7f402a4fd8@kernel.crashing.org> Content-Type: text/plain; charset=ISO-8859-1 Cc: linuxppc-dev@ozlabs.org, linux1394-devel@lists.sourceforge.net, Elimar Riesebieter , Arnd Bergmann , ben.collins@ubuntu.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Segher Boessenkool wrote: >>> I don't know what's to blame for the warnings --- new gcc versions or >>> the change from do { } while (0) to ((void)0)? Either way, the compiler >>> should comprehend that the arguments stuffed into the dma_unmap_single >>> macro are _not_ unused by accident; it should stay quiet and optimize >>> the unused variables away if run with -Osomething. >> >> There is not much that the compiler can do by itself, since the macro >> expansion happens in the preprocessor. > > Even if the compiler could see that the variables are > used as macro arguments, this doesn't automatically > equate to it being able to infer the variables are > unused on purpose. Strange. I believe we had code before with variables that were only used in macros that expanded to , notably debug logging macros which were usually configured out. Perhaps I'm mistaken. -- Stefan Richter -=====-=-=== -=-= =-=-- http://arcgraph.de/sr/