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From: Peter Maydell <peter.maydell@linaro.org>
Date: Wed, 18 Jan 2017 21:53:50 +0000
Message-ID: <CAFEAcA96BYS==gR5dyssGSA++fip0OTRnSidBD7SWq55zc7j=w@mail.gmail.com>
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Subject: Re: [Qemu-devel] [PATCH v2 2/4] compiler: drop ; after BUILD_BUG_ON
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: QEMU Developers <qemu-devel@nongnu.org>, Paolo Bonzini <pbonzini@redhat.com>, Eric Blake <eblake@redhat.com>, Richard Henderson <rth@twiddle.net>

On 18 January 2017 at 21:23, Michael S. Tsirkin <mst@redhat.com> wrote:
> On Wed, Jan 18, 2017 at 11:16:07PM +0200, Michael S. Tsirkin wrote:
>> On Wed, Jan 18, 2017 at 09:04:03PM +0000, Peter Maydell wrote:
>> > On 18 January 2017 at 20:55, Michael S. Tsirkin <mst@redhat.com> wrote:
>> > > All users include the trailing ;, let's require that
>> > > so that uses such as if (a) QEMU_BUILD_BUG_ON(); do not
>> > > produce unexpected results.
>> >
>> > When would it ever make sense for a build-time
>> > assert to be the only thing inside a runtime
>> > conditional anyway?
>> >
>> > thanks
>> > -- PMM
>>
>> What do I know? Do you want to keep the trailing ; in there?
>> I can drop this patch.
>
> Maybe a better justification:
>
>
> QEMU_BUILD_BUG_ON(0)
>
> QEMU_BUILD_BUG_ON(0)
>
> looks ugly but is allowed by the current implementation.
> Let's drop the trailing ; within the macro to make sure all
> users include the ';'.

Yeah, sorry, I should have been clearer -- I think dropping
the trailing semicolon is right, I just thought the
motivating example was a little odd. Not worth a respin
just to fix the commit message.

thanks
-- PMM