diff options
Diffstat (limited to 'contrib/libc++/include')
-rw-r--r-- | contrib/libc++/include/type_traits | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/contrib/libc++/include/type_traits b/contrib/libc++/include/type_traits index f467735..8612e57 100644 --- a/contrib/libc++/include/type_traits +++ b/contrib/libc++/include/type_traits @@ -842,7 +842,16 @@ template <class _T1, class _T2> struct _LIBCPP_TYPE_VIS_ONLY is_convertible namespace __is_convertible_imp { -template <class _Tp> char __test(_Tp); +template <class _Tp> void __test_convert(_Tp); + +template <class _From, class _To, class = void> +struct __is_convertible_test : public false_type {}; + +template <class _From, class _To> +struct __is_convertible_test<_From, _To, + decltype(__test_convert<_To>(_VSTD::declval<_From>()))> : public true_type +{}; + template <class _Tp> __two __test(...); #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES template <class _Tp> _Tp&& __source(); @@ -877,10 +886,8 @@ template <class _T1, class _T2, unsigned _T2_is_array_function_or_void = __is_convertible_imp::__is_array_function_or_void<_T2>::value> struct __is_convertible : public integral_constant<bool, -#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES - sizeof(__is_convertible_imp::__test<_T2>(__is_convertible_imp::__source<_T1>())) == 1 -#else - sizeof(__is_convertible_imp::__test<_T2>(__is_convertible_imp::__source<_T1>())) == 1 + __is_convertible_imp::__is_convertible_test<_T1, _T2>::value +#if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !(!is_function<_T1>::value && !is_reference<_T1>::value && is_reference<_T2>::value && (!is_const<typename remove_reference<_T2>::type>::value || is_volatile<typename remove_reference<_T2>::type>::value) |