Re: [Qemu-devel] [PATCH v3 2/4] qobject: introduce QObjectCommon

[Eric Blake <eblake@redhat.com>]

On 03/29/2018 10:48 AM, Marc-André Lureau wrote:
> By moving the common fields to a QObjectCommon, QObject can be a type
> which also has a 'base' QObjectCommon field. This allows to write a
> generic QOBJECT() macro that will work with any QObject type,
> including QObject itself. The container_of() macro ensures that the
> object to cast has a QObjectCommon base field, give me some type
> safety guarantees. However, for it to work properly, all QObject types
> must have 'base' at offset 0 (which is ensured by static checking from
> previous patch)

Commit message should mention the rationale you gave in v2 of NOT using 
a typedef for QObjectCommon (which was intentional so as to minimize the 
chance that the type gets abused).  We could even go so far as to name 
it QObject_, with trailing underscore, rather than QObjectCommon, to 
make it obvious it is not for normal use.

> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---


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Eric Blake, Principal Software Engineer
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