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From: Duncan Sands <baldrick@wanadoo.fr>
To: Dave Jones <davej@codemonkey.org.uk>
Subject: Re: BUGed to death
Date: Mon, 14 Apr 2003 23:10:05 +0200
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Cc: "Martin J. Bligh" <mbligh@aracnet.com>, Andrew Morton <akpm@digeo.com>,
       linux-kernel <linux-kernel@vger.kernel.org>
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> BUG_ON is already marked unlikely.
> See include/linux/kernel.h
>
> The costs here are doing the actual checks, nothing to do with
> the branch prediction.

Some places don't seem to know about BUG_ON, for example
(from include/linux/skbuff.h):

static inline char *__skb_pull(struct sk_buff *skb, unsigned int len)
{
        skb->len -= len;
        if (skb->len < skb->data_len)
                BUG();
        return skb->data += len;
}