linux-kernel - Question with "container

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <1314701099.1728.6.camel@peter-2ci2c>
Date:	Tue, 30 Aug 2011 18:44:59 +0800
From:	peter <lifulong2c2i2c@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: Question with "container_of(ptr, type, member)"

I have a question about the macro " container_of(ptr, type, member) "
I can write it as this,
 #define container_of(ptr, type, member) ({ \
	(type *) ((char *) ptr - offset_of(type, member)); \
	})
It can act the same as 
#define container_of(ptr, type, member) ({            \
	 const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
	 (type *)( (char *)__mptr - offsetof(type,member) );})
So why we don't use the first one ?
Thanks for your answer.
(I am a kernel newbie ,and sorry for my poor english~)


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/