From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Casting away noderef and address spaces?
Date: Mon, 22 Dec 2008 16:06:13 +1030
Message-ID: <200812221606.13910.rusty@rustcorp.com.au>
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Hi all,

  I need to use typeof(), but I want to change address spaces.  I can't see
how to do that: AFAICT it's not possible.  This doesn't work:

#define __percpu __attribute__((noderef, address_space(3)))

/* Turn v back into a normal var. */
#define convert(v) \
	(*(__attribute__((address_space(0), force)) typeof(&v))(v))

int main(int argc, char *argv)
{
	unsigned int __percpu x;

	convert(x) = 0;
	return 0;
}

Thanks,
Rusty.