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Re: [Xen-devel] uint64_aligned_t not compatible across gcc versions

To: "Keir Fraser" <Keir.Fraser@xxxxxxxxxxxx>
Subject: Re: [Xen-devel] uint64_aligned_t not compatible across gcc versions
From: "Jan Beulich" <jbeulich@xxxxxxxxxx>
Date: Thu, 31 Aug 2006 08:54:16 +0200
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, John Levon <levon@xxxxxxxxxxxxxxxxx>
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>I'll admit there's still the question of whether this is worthwhile for just
>these two hypercalls in the first place. Jan: do you think much code will be
>saved by explicit alignment for domctl/sysctl, or do you think we're just as
>well to remove uint64_aligned_t and XEN_GUEST_HANDLE_64, and do compat shims
>for domctl/sysctl just as we are for all other hypercalls?

Depends on what you mean by code saving - source code or binary size.
The former shouldn't be too much (a simple function with mostly auto-
generated body per translated (sub-)structure), the latter might be
significant (a recompiled version of any non-translated hypercall). Which
variant to use for sysctl and domctl I haven't even started to think about
yet.

But as said in the other mail - it would seem to me that overall it'd be
better to not have this construct.

Jan

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