From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755628AbeDZTZr (ORCPT ); Thu, 26 Apr 2018 15:25:47 -0400 Received: from mail-wr0-f178.google.com ([209.85.128.178]:36164 "EHLO mail-wr0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755422AbeDZTZn (ORCPT ); Thu, 26 Apr 2018 15:25:43 -0400 X-Google-Smtp-Source: AIpwx4+nXElH3uhRQaXEi4F0wcwfrah23SUd9PE+Bzo1FQUjFFqC9DUmDF24OniR5obBH7BTedLhvA== Date: Thu, 26 Apr 2018 22:25:38 +0300 From: Alexey Dobriyan To: Christoph Hellwig Cc: dsterba@suse.cz, akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] proc: use #pragma once Message-ID: <20180426192538.GB4919@avx2> References: <20180423213534.GA9043@avx2> <20180424135409.GA22709@infradead.org> <20180425205531.GA9020@avx2> <20180426102629.scwtdeijbo3342gp@twin.jikos.cz> <20180426103304.GA4639@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180426103304.GA4639@infradead.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 26, 2018 at 03:33:04AM -0700, Christoph Hellwig wrote: > On Thu, Apr 26, 2018 at 12:26:29PM +0200, David Sterba wrote: > > There are about 20k header files, none of them has #pragma once. > > Updating that will bring many unnesessry git commits. > > > > I doubt that one more define in preprocessor tables is a problem we > > should fix. The LOC argument also does not sound very convincing. The > > include protection is at the top of the file, not mixed among other > > code. Replacing 2-3 lines with one will be barely noticeable. > > Let's put it another way: does this make any noticable difference > for compile times? Should be the same as include guard pattern is recognized and becomes #pragma once internally.