Predefined macros for rvalue reference support?

[Peter Dimov]

David Fang wrote:
>> Can someone please tell me how a library can detect whether the
>> compiler supports rvalue references? I'm trying to enable move
>> support for boost::shared_ptr. Thanks.
>
> Hi,
> Do you mean at configure-time?

No, I need a compile time check. The Boost config system is not 
configure-based; it relies on the predefined preprocessor macros.