Prefer to use the __is_XXX compiler intrinsics to the (old, busted) __has_XXX intrinsics when implementing type traits. Thanks to Richard Smith for the patch.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@344254 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/type_traits b/include/type_traits
index 7ff67bf..4a50437 100644
--- a/include/type_traits
+++ b/include/type_traits
@@ -3686,7 +3686,12 @@
// is_trivially_destructible
-#if __has_feature(has_trivial_destructor) || (_GNUC_VER >= 403)
+#if __has_keyword(__is_trivially_destructible)
+
+template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_destructible
+ : public integral_constant<bool, __is_trivially_destructible(_Tp)> {};
+
+#elif __has_feature(has_trivial_destructor) || (_GNUC_VER >= 403)
template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_destructible
: public integral_constant<bool, is_destructible<_Tp>::value && __has_trivial_destructor(_Tp)> {};
@@ -3713,18 +3718,15 @@
// is_nothrow_constructible
-#if 0
-template <class _Tp, class... _Args>
-struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
- : public integral_constant<bool, __is_nothrow_constructible(_Tp(_Args...))>
-{
-};
-
-#else
-
#ifndef _LIBCPP_HAS_NO_VARIADICS
-#if __has_feature(cxx_noexcept) || (_GNUC_VER >= 407 && __cplusplus >= 201103L)
+#if __has_keyword(__is_nothrow_constructible)
+
+template <class _Tp, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
+ : public integral_constant<bool, __is_nothrow_constructible(_Tp, _Args...)> {};
+
+#elif __has_feature(cxx_noexcept) || (_GNUC_VER >= 407 && __cplusplus >= 201103L)
template <bool, bool, class _Tp, class... _Args> struct __libcpp_is_nothrow_constructible;
@@ -3761,7 +3763,7 @@
{
};
-#else // __has_feature(cxx_noexcept)
+#else // __has_keyword(__is_nothrow_constructible) || __has_feature(cxx_noexcept)
template <class _Tp, class... _Args>
struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
@@ -3817,6 +3819,23 @@
#else // _LIBCPP_HAS_NO_VARIADICS
+#if __has_keyword(__is_nothrow_constructible)
+
+template <class _Tp, class _A0 = __is_construct::__nat,
+ class _A1 = __is_construct::__nat>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
+ : public integral_constant<bool, __is_nothrow_constructible(_Tp, _A0, _A1)> {};
+
+template <class _Tp, class _A0>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, _A0>
+ : public integral_constant<bool, __is_nothrow_constructible(_Tp, _A0)> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp>
+ : public integral_constant<bool, __is_nothrow_constructible(_Tp)> {};
+
+#else // __has_keyword(__is_nothrow_constructible)
+
template <class _Tp, class _A0 = __is_construct::__nat,
class _A1 = __is_construct::__nat>
struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
@@ -3868,8 +3887,8 @@
{
};
+#endif // __has_keyword(__is_nothrow_constructible)
#endif // _LIBCPP_HAS_NO_VARIADICS
-#endif // __has_feature(is_nothrow_constructible)
#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
template <class _Tp, class ..._Args>
@@ -3919,7 +3938,13 @@
// is_nothrow_assignable
-#if __has_feature(cxx_noexcept) || (_GNUC_VER >= 407 && __cplusplus >= 201103L)
+#if __has_keyword(__is_nothrow_assignable)
+
+template <class _Tp, class _Arg>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable
+ : public integral_constant<bool, __is_nothrow_assignable(_Tp, _Arg)> {};
+
+#elif __has_feature(cxx_noexcept) || (_GNUC_VER >= 407 && __cplusplus >= 201103L)
template <bool, class _Tp, class _Arg> struct __libcpp_is_nothrow_assignable;
@@ -3941,7 +3966,7 @@
{
};
-#else // __has_feature(cxx_noexcept)
+#else // __has_keyword(__is_nothrow_assignable) || __has_feature(cxx_noexcept)
template <class _Tp, class _Arg>
struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable