From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from [140.186.70.92] (port=56697 helo=eggs.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1OTFDS-00034G-Lx
	for qemu-devel@nongnu.org; Mon, 28 Jun 2010 10:21:47 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69)
	(envelope-from <blauwirbel@gmail.com>) id 1OTFDR-0006e8-Iy
	for qemu-devel@nongnu.org; Mon, 28 Jun 2010 10:21:42 -0400
Received: from mail-pv0-f173.google.com ([74.125.83.173]:40720)
	by eggs.gnu.org with esmtp (Exim 4.69)
	(envelope-from <blauwirbel@gmail.com>) id 1OTFDR-0006dt-E2
	for qemu-devel@nongnu.org; Mon, 28 Jun 2010 10:21:41 -0400
Received: by pvg12 with SMTP id 12so2572424pvg.4
	for <qemu-devel@nongnu.org>; Mon, 28 Jun 2010 07:21:40 -0700 (PDT)
MIME-Version: 1.0
In-Reply-To: <4C2857A5.20206@redhat.com>
References: <1277470342-5861-1-git-send-email-pbonzini@redhat.com>
	<1277470342-5861-5-git-send-email-pbonzini@redhat.com>
	<AANLkTikFdQFCcaMfc_gTGpp-gg1njv0khAgh5LEeLVKZ@mail.gmail.com>
	<4C2857A5.20206@redhat.com>
From: Blue Swirl <blauwirbel@gmail.com>
Date: Mon, 28 Jun 2010 14:21:20 +0000
Message-ID: <AANLkTin7paGTSyemmA4z04w9NU4avaZtosO6QnJ5AFoj@mail.gmail.com>
Subject: Re: [Qemu-devel] [PATCH 4/7] provide opaque CPUState to files that
	are compiled once
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>, Isaku Yamahata <yamahata@valinux.co.jp>, qemu-devel@nongnu.org

On Mon, Jun 28, 2010 at 8:04 AM, Paolo Bonzini <pbonzini@redhat.com> wrote:
> On 06/27/2010 09:17 PM, Blue Swirl wrote:
>>
>> I'm not comfortable with this part. Accidental use of the global
>> register variable can cause subtle bugs. I'd rather rename 'env' to
>> something more obvious and less likely to collide, like
>> 'global_reg_env' and always poison that. Then we could replace 'env1'
>> etc with just 'env'.
>
> This is not very different from before thanks to the reordering of includ=
es
> done in this patch.
>
> All target-*/exec.h files now start with
>
> #include "config.h"
> #include "dyngen-exec.h"
> #include "cpu.h"
> #include "exec-all.h"
>
> // sometimes a few #defines
>
> register struct CPUAlphaState *env asm(AREG0);
>
> And so they cannot use the global env unless NEED_CPU_H is defined. =C2=
=A0If
> anything, it's clearer than before because the structure of the initial
> #includes is the same for all targets.
>
> It's true that a "NEED_GLOBAL_ENV" would provide even better safety, but
> that's something for a separate patch series. =C2=A0It's particularly eas=
y to do
> after replacing CPU<Target>State with CPUState, so that it can be moved i=
nto
> exec-all.h, but this series is already big enough IMO. =C2=A0Let's do cle=
anups
> one thing at a time please.

Fine, but then let's not unpoison env with this patch set, please.