From: =?UTF-8?Q?Am=C3=A9rico_Wang?= <xiyou.wangcong@gmail.com>
Subject: Re: [PATCH] jbd/jbd2: add pointer type conversion on void *arg from
 void * to journal_t * explicitly in kjournald/kjournald2
Date: Wed, 3 Aug 2011 10:52:47 +0800
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Cc: Li Zefan <lizf@cn.fujitsu.com>, "Theodore Ts'o" <tytso@mit.edu>,
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To: Wang Sheng-Hui <shhuiw@gmail.com>
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On Wed, Aug 3, 2011 at 10:17 AM, Wang Sheng-Hui <shhuiw@gmail.com> wrote:
>
> I remember any * can be assigned directly to void * in ANSI C, but
> void * should be converted to specific point * type. Right?
>

C99 6.3.2.3

A pointer to void may be converted to or from a pointer to any
incomplete or object
type. A pointer to any incomplete or object type may be converted to a
pointer to void
and back again; the result shall compare equal to the original pointer.