Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932896AbXAAEbl (ORCPT ); Sun, 31 Dec 2006 23:31:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932898AbXAAEbl (ORCPT ); Sun, 31 Dec 2006 23:31:41 -0500 Received: from gate.crashing.org ([63.228.1.57]:37588 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932896AbXAAEbl (ORCPT ); Sun, 31 Dec 2006 23:31:41 -0500 In-Reply-To: <45987EB0.1020505@oracle.com> References: <20061231194501.GE3730@rhun.ibm.com> <66cc662565c489fa9e604073ced64889@kernel.crashing.org> <45987EB0.1020505@oracle.com> Mime-Version: 1.0 (Apple Message framework v623) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <8952abefff5a73bf24a0c80936fe7091@kernel.crashing.org> Content-Transfer-Encoding: 7bit Cc: Muli Ben-Yehuda , Linux kernel mailing list , "Robert P. J. Day" , trivial@kernel.org From: Segher Boessenkool Subject: Re: [PATCH] Documentation: Explain a second alternative for multi-line macros. Date: Mon, 1 Jan 2007 05:31:32 +0100 To: Randy Dunlap X-Mailer: Apple Mail (2.623) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 866 Lines: 29 >>> #define setcc(cc) ({ \ >>> partial_status &= ~(SW_C0|SW_C1|SW_C2|SW_C3); \ >>> partial_status |= (cc) & (SW_C0|SW_C1|SW_C2|SW_C3); }) >> This _does_ return a value though, bad example. > > Where does it return a value? partial_status |= > I don't see any uses of it Ah, that's a separate thing -- it returns a value, it's just never used. > And with a small change to put it inside a do-while block > instead of ({ ... }), it at least builds cleanly. Well please replace it then, statement expressions should be avoided where possible (to start with, they don't have well- defined semantics). Segher - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/