+#ifndef __has_feature
+# define __has_feature(x) 0
+#endif
+
+/// LLVM_HAS_RVALUE_REFERENCES - Does the compiler provide r-value references?
+/// This implies that <utility> provides the one-argument std::move; it
+/// does not imply the existence of any other C++ library features.
+#if (__has_feature(cxx_rvalue_references) \
+ || defined(__GXX_EXPERIMENTAL_CXX0X__) \
+ || _MSC_VER >= 1600)
+#define LLVM_USE_RVALUE_REFERENCES 1
+#else
+#define LLVM_USE_RVALUE_REFERENCES 0
+#endif
+
+/// llvm_move - Expands to ::std::move if the compiler supports
+/// r-value references; otherwise, expands to the argument.
+#if LLVM_USE_RVALUE_REFERENCES
+#define llvm_move(value) (::std::move(value))
+#else
+#define llvm_move(value) (value)
+#endif
+
+/// LLVM_DELETED_FUNCTION - Expands to = delete if the compiler supports it.
+/// Use to mark functions as uncallable. Member functions with this should
+/// be declared private so that some behaivor is kept in C++03 mode.
+///
+/// class DontCopy {
+/// private:
+/// DontCopy(const DontCopy&) LLVM_DELETED_FUNCTION;
+/// DontCopy &operator =(const DontCopy&) LLVM_DELETED_FUNCTION;
+/// public:
+/// ...
+/// };
+#if (__has_feature(cxx_deleted_functions) \
+ || defined(__GXX_EXPERIMENTAL_CXX0X__))
+ // No version of MSVC currently supports this.
+#define LLVM_DELETED_FUNCTION = delete
+#else
+#define LLVM_DELETED_FUNCTION
+#endif
+