How to detect C++11 features when clang does not have the querying macros?

Clang Frontend
1

Boost.Config recently added a macro to detect support for
local types as template arguments (N2657).
But clang does not have a querying macro for this feature.
How can we detect the support for it?

More generally, what is a reasonable way to detect support for features
when clang does not have the corresponding querying macro?
Do we need nasty version checks in this case?

Regards,
Michel