When I first saw this topic, I thought it was outside the scope of SG10.
Our purpose, as I see it, is to smooth the steps between revisions of
the standard. The ABI is really an implementation detail.

But we can certainly explore the idea.

> libc++ would like to support both the itanium and the Microsoft
> ABIs. This leaks into the header through type_info. The macro
> would help correctly build and configure checks to ensure that the
> ABI matches.
>
> Having the macro defined would allow the headers to inject code into
> the user application to ensure the ABI matches at link time without
> having the user specify the ABI they believe the compiler to be
> using.

Please provide an example of code you would like to write using the
macro you are asking for.

Clark