So I dunno. I still lean toward BOOST_NO_DECLTYPE_N3276 because nothing pithy seems to really get at the gist of it. And I don't expect this macro to be used outside of Boost itself. But I don't have a strong feeling about it.
How about some documentation or at least a comment somewhere in Boost.Config about what it implies, even if it's just a link to the paper?
I'd reckon that anyone that encounters it in source will want to try to find out what it means, in some indirect way.
That's what we do, the docs for that macro just say: The compiler does not support the extension to `decltype` described in [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3276.pdf N3276], accepted in Madrid, March 2011. Which is pretty short granted, but at a link to the paper is there. HTH, John.