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Date: Thu, 19 Dec 2013 21:42:58 +0800
From: Chen Gang <gang.chen.5i5j@gmail.com>
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To: Vineet Gupta <Vineet.Gupta1@synopsys.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Francois Bedard <Francois.Bedard@synopsys.com>,
        David Howells <dhowells@redhat.com>, Arnd Bergmann <arnd@arndb.de>
Subject: Re: [PATCH] Revert "ARC: Add guard macro to uapi/asm/unistd.h"
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On 12/19/2013 09:11 PM, Vineet Gupta wrote:
> On 12/19/2013 06:04 PM, Chen Gang wrote:
>> On 12/19/2013 07:13 PM, Vineet Gupta wrote:
>>>> This reverts commit 97bc386fc12deeb41d5bff33548e3002b258d4e0.
>>>>
>>>> Generic syscall table generator relies on ARCH unistd.h as follows:
>>>>
>>>> 	void *sys_call_table[NR_syscalls] = {
>>>> 		[0 ... NR_syscalls-1] = sys_ni_syscall,
>>>> 	#include <asm/unistd.h>
>>>> 	};
>>>>
>>>> And turns out that prior dependencies already include that header by
>>>> the time preprocessor hits the above. Meaning ARCH unistd.h needs to be
>>>> able to included twice.
>>>>
>> OK, thanks, it sounds reasonable to me.
>>
>> But why many other architectures contents these guard macros? (arm, sh,
>> blackfin, cris, frv, ia64, m32r, m68k, mips, s390, microblaze, mn10300,
>> parisc, powerpc, sparc, x86). Do they need improvement too?
>>
>> And for our case, what xtensa has done looks like a better way to me.
> 
> Yeah, looks like that'll work - good find. Linus, please ignore the Revert, I'll
> follow up with a pull request.
> 

Thanks.  :-)

> -Vineet
> 


-- 
Chen Gang

Open, share and attitude like air, water and life which God blessed