From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752273Ab3KUKzp (ORCPT <rfc822;w@1wt.eu>);
	Thu, 21 Nov 2013 05:55:45 -0500
Received: from mail-pb0-f41.google.com ([209.85.160.41]:44702 "EHLO
	mail-pb0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1750913Ab3KUKzn (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 21 Nov 2013 05:55:43 -0500
Message-ID: <528DE731.6040200@gmail.com>
Date: Thu, 21 Nov 2013 18:57:53 +0800
From: Chen Gang <gang.chen.5i5j@gmail.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2
MIME-Version: 1.0
To: Vineet Gupta <Vineet.Gupta1@synopsys.com>
CC: linux-kernel@vger.kernel.org,
        Francois Bedard <Francois.Bedard@synopsys.com>,
        Ingo Molnar <mingo@kernel.org>, David Howells <dhowells@redhat.com>
Subject: Re: [PATCH] ARC: Add guard macro to uapi/asm/unistd.h
References: <1385029778-26092-1-git-send-email-vgupta@synopsys.com>
In-Reply-To: <1385029778-26092-1-git-send-email-vgupta@synopsys.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 11/21/2013 06:29 PM, Vineet Gupta wrote:
> Chen originally proposed this as "right thing to do" however I
> actually ran into this when building perf tools. Some of the utils
> include unistd.h as well as linux/unistd.h. Since -I includes kernel
> headers too, we end up including the ARC unistd.h twice, leading to
> redefinition nwarnings.
> 
> ------------------>8-------------------
>     CC bench/sched-pipe.o
> In file included from ~/kernel/arch/arc/include/uapi/asm/unistd.h:21:0,
>                  from ~/kernel/include/uapi/linux/unistd.h:7,
>                  from bench/sched-pipe.c:24:
> ~/kernel/include/uapi/asm-generic/unistd.h:889:0: error: "__NR_fcntl64"
> redefined [-Werror]
>  #define __NR_fcntl64 __NR3264_fcntl
>  ^
> In file included from
> ~/gnu/arc-linux-uclibc/sys-include/sys/syscall.h:24:0,
>                  from bench/../perf.h:112,
>                  from bench/sched-pipe.c:13:
> ~/gnu/arc-linux-uclibc/include/bits/sysnum.h:761:0: note: this is the
> location of the previous definition
> ------------------>8-------------------
> 
> Verified that make headers_install works fine with this.
> 
> Suggested-by: Chen Gang <gang.chen.5i5j@gmail.com>
> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
> Cc: David Howells <dhowells@redhat.com>
> ---
> I will be adding this to arc tree for 3.13
> ---
>  arch/arc/include/uapi/asm/unistd.h | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/arch/arc/include/uapi/asm/unistd.h b/arch/arc/include/uapi/asm/unistd.h
> index 6f30484f34b7..68125dd766c6 100644
> --- a/arch/arc/include/uapi/asm/unistd.h
> +++ b/arch/arc/include/uapi/asm/unistd.h
> @@ -8,6 +8,9 @@
>  
>  /******** no-legacy-syscalls-ABI *******/
>  
> +#ifndef _UAPI_ASM_ARC_UNISTD_H
> +#define _UAPI_ASM_ARC_UNISTD_H
> +
>  #define __ARCH_WANT_SYS_EXECVE
>  #define __ARCH_WANT_SYS_CLONE
>  #define __ARCH_WANT_SYS_VFORK
> @@ -32,3 +35,5 @@ __SYSCALL(__NR_arc_gettls, sys_arc_gettls)
>  /* Generic syscall (fs/filesystems.c - lost in asm-generic/unistd.h */
>  #define __NR_sysfs		(__NR_arch_specific_syscall + 3)
>  __SYSCALL(__NR_sysfs, sys_sysfs)
> +
> +#endif
> 

Is it better to append comment for "#endif"?

e.g. "#endif /* _UAPI_ASM_ARC_UNISTD_H */"


Thanks.
-- 
Chen Gang