[cxx-abi-dev] Passing non-trivial types through ...

[John McCall]

On Aug 13, 2014, at 3:05 PM, Nelson, Clark <clark.nelson at intel.com> wrote:
>> I agree that this is a problem; we shouldn't "standardize"
>> something that a vendor doesn't feel they can reasonably adopt.
>> 
>> We could document it as a recommendation, I suppose.
> 
> Technically, if the ABI doesn't actually nail it down, then it's not really part of the ABI, is it?

We’ve discussed having recommendations in the document before; I don’t recall what they were specifically for.

> But it doesn't have to be part of the ABI for G++ to allow it and do something for it.

This is clearly the right way for any vendor who wants to accept non-POD variadic arguments to do it: no solution involving memcpy can be correct for all types, and doing something MSVC-like but only for variadics would be very strange.  I think that’s worth documenting.

John.