@@ -1185,6 +1185,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
};
/// @cond undocumented
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__add_rvalue_reference)
+ template<typename _Tp>
+ struct __add_rvalue_reference_helper
+ { using type = __add_rvalue_reference(_Tp); };
+#else
template<typename _Tp, typename = void>
struct __add_rvalue_reference_helper
{ using type = _Tp; };
@@ -1192,6 +1197,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Tp>
struct __add_rvalue_reference_helper<_Tp, __void_t<_Tp&&>>
{ using type = _Tp&&; };
+#endif
template<typename _Tp>
using __add_rval_ref_t = typename __add_rvalue_reference_helper<_Tp>::type;
@@ -1748,9 +1754,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
#endif
/// add_rvalue_reference
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__add_rvalue_reference)
+ template<typename _Tp>
+ struct add_rvalue_reference
+ { using type = __add_rvalue_reference(_Tp); };
+#else
template<typename _Tp>
struct add_rvalue_reference
{ using type = __add_rval_ref_t<_Tp>; };
+#endif
#if __cplusplus > 201103L
/// Alias template for remove_reference
This patch optimizes the compilation performance of std::add_rvalue_reference by dispatching to the new __add_rvalue_reference built-in trait. libstdc++-v3/ChangeLog: * include/std/type_traits (add_rvalue_reference): Use __add_rvalue_reference built-in trait. (__add_rvalue_reference_helper): Likewise. Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org> --- libstdc++-v3/include/std/type_traits | 12 ++++++++++++ 1 file changed, 12 insertions(+)