Re: [Qemu-devel] [PATCH 2/3] qobject: assume base of a qobject is at offset 0 - Marc-André Lureau

From: "Marc-André Lureau" <marcandre.lureau@redhat.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel <qemu-devel@nongnu.org>,
	"P. Berrange, Daniel" <berrange@redhat.com>,
	"Blake, Eric" <eblake@redhat.com>,
	"Armbruster, Markus" <armbru@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 2/3] qobject: assume base of a qobject is at offset 0
Date: Wed, 21 Mar 2018 17:11:05 +0100	[thread overview]
Message-ID: <CAMxuvawM+oOH7wHEMdcjJAZVaL9PbjfHA+UfMLu5+SbZgchrTw@mail.gmail.com> (raw)
In-Reply-To: <407fd6f2-b88f-02fd-b4f8-9b4abb6a03a9@redhat.com>

Hi

On Wed, Mar 21, 2018 at 5:00 PM, Paolo Bonzini <pbonzini@redhat.com> wrote:
> On 21/03/2018 16:55, Marc-André Lureau wrote:
>> That would work with an anonymous union though:
>>
>> struct QObject {
>>     union {
>>         QType type;
>>         QType base;
>>     };
>>     size_t refcnt;
>> };
>>
>> If it's acceptable, I think I'll take this approach.
>
> You don't need QEMU_GENERIC at all then, don't you?

Ah ah, that's what I thought too, but the type of QObject * &x->base
isn't QObject * :)

I don't think we can fool it there (without loosing some type safety)