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Date: Wed, 11 Jan 2006 00:36:08 -0800 (PST)
Message-Id: <20060111.003608.126208924.davem@davemloft.net>
To: arjan@infradead.org
Cc: drepper@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: ntohs/ntohl and bitops
From: "David S. Miller" <davem@davemloft.net>
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From: Arjan van de Ven <arjan@infradead.org>
Date: Wed, 11 Jan 2006 09:13:11 +0100

> > The first suggestion isn't considered ugly, and the best form is:
> > 
> > 	if (ih->frag_off & __constant_htons(IP_OFFSET))
> 
> why this __constant_htons and not just plain htons ??
> htons() gets auto-remapped to that anyway via the builtin "is this a
> constant" thing...... and to be honest htons() is more readable.

You're right.

We use the __constant_*() things for structure initialization
which needs to be compile time.