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Question

How can I check whether my compiler supports rvalue references or not? Is there a standard preprocessor macro, or do different compilers have different macros? Ideally, I would want to write this:

#ifdef RVALUE_REFERENCES_SUPPORTED

foobar(foobar&& that)
{
    // ...
}

#endif

Answer 1

I'm not aware of any standard preprocessor macro, but:

• Visual Studio introduced support in VC2010, whose internal version is 1600, so you can check with _MSC_VER >= 1600
• GCC has supported rvalue references since version 4.3 , so you can check for that version along with __GXX_EXPERIMENTAL_CXX0X__
• Clang defines __has_feature macros for doing exactly what you need: __has_feature(cxx_rvalue_references)

So for most common compilers, it should be fairly easy to cobble something together yourself.

I am also pretty sure that Boost has a macro for this purpose, which you may be able to use if your project includes Boost (otherwise you could look at their implementation)

Answer 2

Boost.Config有BOOST_NO_RVALUE_REFERENCES 。

Answer 3

The standard method is to check the standard version : If __cplusplus==199711L then you don't have (standard) rvalue references. If __cplusplus==201103L , you do. Obviously, this doesn't cover non-standard compilers or non-standard extensions to C++98.