Re: [Qemu-devel] [PATCH v3 14/14] pci: Tidy up PCI host bridges

[Andreas Färber]

Am 05.07.2012 11:53, schrieb Paolo Bonzini:
> Il 05/07/2012 00:34, Andreas Färber ha scritto:
>>>> Just to clarify: replacing upcasts which are always safe
>>>> with downcasts which can fail is what I consider especially ugly.
>> As per Anthony the parent field in the QOM instance structs is not
>> supposed to be touched (cf. object.h). We mark it /*< private >*/ so
>> that it doesn't even show up in gtk-doc documentation. If it is unused,
>> its name becomes irrelevant and could even be "reserved" if we so
>> wanted. Renaming it to whatever proves that all old references are gone.
> 
> I disagree with removing static checks whenever possible.
> 
>> Background is that qdev and QOM work differently with regards to
>> inheritance: as mentioned in the preceding patch, for qdev the parent
>> was (had to be) identified by name and could be anywhere in the struct;
> 
> Not entirely true, being at the beginning of the struct is already
> enforced by using DO_UPCAST (which is admittedly a strange name for a
> downcast macro) instead of container_of.

If you look at the patchset you will find that it was not properly enforced!

Andreas

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