[cfe-dev] [PATCH] extend __interface support

[David Robins]

On Mon, Aug 13, 2012 at 12:39:05AM -0700, John McCall wrote:
> Is this implicitly an answer to my previous message?  That is, are you
> saying that __interface cannot be used in elaborated type specifiers?
> Please do test this;  the right way to model this feature depends on
> how it fits in the language.

I answered the questions ("can you write...") in a reply to your message
in the previous thread.

You said in a previous message to João Matos:

> Thanks.  In that case, I definitely don't think we want to model this with
> macros and attributes * MSVC is clearly treating __interface as a fourth
> kind of class-key, and that's the appropriate way to model it.

I'm happy to rework the patch; but if you have the time could you
explain the difference? By "fourth kind of class-key" (I understand
class-key from the C++ spec) do you mean that it should have its own
decl spec type TST_interface and TagTypeKind TTK_Interface rather than
the ms_interface attribute?

Note that MS diagnostics refer to __interface as 'struct', e.g.

	int.cpp(4) : warning C4099: 'Y' : type name first seen using 'struct'
	now seen using 'class'

Does that matter at all?