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Re: [Xen-devel] netfront: rx->offset: 12, size: 4294967295

To: keir@xxxxxxxxxxxxx (Keir Fraser)
Subject: Re: [Xen-devel] netfront: rx->offset: 12, size: 4294967295
From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Date: Wed, 06 Jun 2007 07:48:23 +1000
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, jajcus@xxxxxxxxxx
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Keir Fraser <keir@xxxxxxxxxxxxx> wrote:
> 
> My suspicion is that, strictly speaking, the assignment of 1 to
> copying_receiver is invalid because a single-bit bitfield can only hold the
> values -1 and 0. Older gcc perhaps mapped 1 to -1, but 4.2.0 is mapping 1 to
> 0 (or choosing to do that as an optimisation, since it has the choice, and
> hence can simplify the code to always write zero in this case). That sucks.

That's why we always use unsigned for bitfields in Linux.

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@xxxxxxxxxxxxxxxxxxx>
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