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Re: C++ PATCH: Old ABI compatibility
>>>>> Chip Salzenberg <chip@valinux.com> writes:
> According to Jason Merrill:
>> >>>>> Chip Salzenberg <chip@valinux.com> writes:
>> > True, BUT: Is it at least safe to assume that single, non-virtual
>> > inheritance results in no deltas?
>>
>> No. If the base class has no virtual functions, but the derived class
>> does, the vptr will be added before the base subobject.
> Good point. Another assumption I didn't think of is that the base
> class already has virtuals, and thus a vtbl.
In that case, the new ABI will not produce deltas in that case. But you
still shouldn't rely on that, since the standard guarantees nothing about
the layout of non-PODs.
Jason