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Date: Sat, 11 Jun 2005 19:24:19 +0200
From: Willy Tarreau <willy@w.ods.org>
To: Jan Engelhardt <jengelh@linux01.gwdg.de>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Assuming NULL
Message-ID: <20050611172419.GE28759@alpha.home.local>
References: <Pine.LNX.4.61.0506111823440.19223@yvahk01.tjqt.qr>
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Hi Jan,

On Sat, Jun 11, 2005 at 06:24:22PM +0200, Jan Engelhardt wrote:
(...)
> My question is: Which one is right wrt the case "i_op ==/!= NULL"?
> There are two ways:
> 
> - the kernel assumes i_op (and similar) is always non-NULL
>   => then we can remove a lot of checks, like the first example above
> 
> - the kernel does not assume...
>   => then we need some extra checks, like in the second example above

and in any case, adding a comment telling why it CAN or why it CANNOT
be NULL would prevent other people from having to redo the same work
in 6 months.

Willy