Subject: Re: [PATCH] ubi: kill homegrown endian macros
From: David Woodhouse <dwmw2@infradead.org>
To: "John Anthony Kazos Jr." <jakj@j-a-k-j.com>
Cc: Matthieu CASTET <castet.matthieu@free.fr>, linux-kernel@vger.kernel.org
In-Reply-To: <alpine.DEB.0.99.0705180750550.8830@sigma.j-a-k-j.com>
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	 <20070517102931.6bbbad1a.akpm@linux-foundation.org>
	 <pan.2007.05.17.20.30.30@free.fr>
	 <1179455959.2859.527.camel@shinybook.infradead.org>
	 <alpine.DEB.0.99.0705172254560.27207@sigma.j-a-k-j.com>
	 <1179458274.2859.538.camel@shinybook.infradead.org>
	 <alpine.DEB.0.99.0705180750550.8830@sigma.j-a-k-j.com>
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Date: Fri, 18 May 2007 22:52:39 +0800
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On Fri, 2007-05-18 at 07:52 -0400, John Anthony Kazos Jr. wrote:
> Out of curiosity, why would a compiler ever insert padding in a structure 
> that has all its elements properly-aligned? 

Well, it might decide it would be nicer if some elements were aligned to
64 bits. Or to a cache line. Or something. I don't care about _why_ --
the point is that it's _allowed_ to. Hence the original use of
__attribute__((packed)).

In practice, there's no real reason why it would do such a thing, which
is why I removed the packed attribute and replaced it with a runtime
check on the size of the structures in question.

-- 
dwmw2

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