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Subject: Re: [PATCH v8 2/6] time: sync read_boot_clock64() with persistent
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To: Pavel Tatashin <pasha.tatashin@oracle.com>
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From: Dou Liyang <douly.fnst@cn.fujitsu.com>
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Date: Wed, 15 Nov 2017 10:47:45 +0800
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Hi Pavel,

At 11/15/2017 03:57 AM, Pavel Tatashin wrote:
>> why we should remove the *extern* keyword?
>
> Hi Dou,
>
> While, I am not sure why it was decided to stop using externs in
> headers, this is a warning printed by scripts/checkpatch.pl:
>
> CHECK: extern prototypes should be avoided in .h files
>
> To have a clean checkpatch output I removed externs.
>

I see.

IMO, using the extern keyword on function prototypes in *.h files
is superfluous, but, It doesn't matter for functionality. *extern*
is default keywords.

AFAIK, it's a code style problem. In x86 arch, we prefer to
keep *extern* explicitly, so, let's keep it like before for
code consistency.

Thank,
	dou