From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [PATCH 08 of 15] hvmloader: Add a simple "scratch
	allocator"
Date: Thu, 02 Jun 2011 21:00:47 +0100
Message-ID: <CA0DAA7F.1B8A7%keir.xen@gmail.com>
References: <20110602194331.GA32344@dumpdata.com>
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To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>, Ian Campbell <ian.campbell@citrix.com>
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On 02/06/2011 20:43, "Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com> wrote:

>> +    return (void *)(unsigned long)s;
> 
> Why the double cast?

gcc complains if you cast between a pointer and an integer of a different
size. We assume in many places that a pointer is same size as a long, so we
cast through a long when the original integer type may be different size. In
this case, in hvmloader, we know that pointers/longs/uint32_t are all
32-bit, but still I quite like the principle of always casting through a
long when the integer is not explicitly that type already.

 -- Keir