Re: [Qemu-devel] [RFC v0 5/8] object: make interfaces concrete

["Andreas Färber" <afaerber@suse.de>]

Am 13.06.2012 12:03, schrieb Paolo Bonzini:
> Il 13/06/2012 11:38, Peter A. G. Crosthwaite ha scritto:
>> Objects that define interface delegate the creation of the interface object
>> to the interface type. These means that object_new() when called recursively by

I am pretty certain that object_new() is NOT called recursively! The
static helpers of object_instantiate() are, and abstractness should not
matter there or none of the, e.g., CPU subclasses could be created... So
if there is a problem this description is bogus.

>> the interface instantior is going to bork because its trying to instantiate
>> an abstract type. Fixed by making interface types concrete.
>>
>> Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
>> ---
>>  qom/object.c |    2 +-
>>  1 files changed, 1 insertions(+), 1 deletions(-)
>>
>> diff --git a/qom/object.c b/qom/object.c
>> index 1eba795..c3a7a47 100644
>> --- a/qom/object.c
>> +++ b/qom/object.c
>> @@ -191,7 +191,7 @@ static void type_class_interface_init(TypeImpl *ti, InterfaceImpl *iface)
>>          .parent = iface->parent,
>>          .class_size = sizeof(InterfaceClass),
>>          .class_init = iface->interface_initfn,
>> -        .abstract = true,
>> +        .abstract = false,
>>      };
>>      char *name = g_strdup_printf("<%s::%s>", ti->name, iface->parent);
>>  
>>
> 
> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

Why? Object is abstract, too, and in patch 3/8 a type is being derived
from TYPE_INTERFACE. So if we want to make interface non-abstract then
we don't need the Container type either since it is simply the
non-abstract version of Object. My guess is that, if at all, something
else is going wrong and this is papering over it.

Andreas

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