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Date: Wed, 9 May 2007 00:07:46 +0300
From: Giorgos Keramidas <keramida@ceid.upatras.gr>
To: John Baldwin <jhb@freebsd.org>
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Cc: freebsd-arch@freebsd.org, Julian Elischer <julian@elischer.org>,
	Hans Petter Selasky <hselasky@c2i.net>
Subject: Re: Missing LIST_PREV() ?
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On 2007-05-08 16:58, John Baldwin <jhb@freebsd.org> wrote:
> On Tuesday 08 May 2007 03:00:51 pm Hans Petter Selasky wrote:
> > I suggested the following at hacker's:
> >
> > #define LIST_PREV(head,elm,field,type) \
> >  (((elm) == LIST_FIRST(head)) ? ((struct type *)0) : \
> >   ((struct type *)(((uint8_t *)((elm)->field.le_prev)) - \
> >                    ((uint8_t *)&LIST_NEXT((struct type *)0,field)))))
> >
> > What do you think?
>
> Just use a TAILQ, that's what it is there for.

The macro is interesting, but I wouldn't feel safe using it.

I didn't receive the hackers post, but I fully agree.  Please just use
TAILQ.  No pointer-hacks are needed, it's there already, it works as
expected on all the cases I've seen... what more do we need?