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Date: Mon, 19 May 2008 07:55:04 +0200
From: Christoph Hellwig <hch@lst.de>
To: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Al Viro <viro@ZenIV.linux.org.uk>, Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 2/6] ERR_PTR: add ERR_OR_0_PTR
Message-ID: <20080519055504.GB14902@lst.de>
References: <20080513201813.GA5869@joi> <1211148067-16130-1-git-send-email-marcin.slusarz@gmail.com>
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On Mon, May 19, 2008 at 12:01:07AM +0200, Marcin Slusarz wrote:
> Some codepaths call ERR_PTR with possibly 0 argument, which is not
> a valid errno and rely on conversion from 0 to NULL pointer.
> Add ERR_OR_0_PTR function which accepts errnos and 0 as an argument.

Sorry, no.  ERR_PTR(0) is perfectly valid, you just don't want to return
the actualy value.  E.g. we have a common idiom of:

	some_ptr = ERR_PTR(err);
	if (IS_ERR(some_ptr))
		goto out_handle_err;

and obsfucating this with new syntactic sugar is not a good idea.