Implement C++17 variable templates for type traits.

	* include/std/chrono (treat_as_floating_point_v): New.
	* include/std/ratio (ratio_equal_v, ratio_not_equal_v)
	(ratio_less_v, ratio_less_equal_v, ratio_greater_v)
	(ratio_greater_equal_v): Likewise.
	* include/std/system_error (is_error_code_enum_v)
	(is_error_condition_enum_v): Likewise.
	* include/std/tuple (tuple_size_v): Likewise.
	* type_traits (conjunction_v, disjunction_v, negation_v)
	(is_void_v, is_null_pointer_v, is_integral_v, is_floating_point_v)
	(is_array_v, is_pointer_v, is_lvalue_reference_v)
	(is_rvalue_reference_v, is_member_object_pointer_v)
	(is_member_function_pointer_v, is_enum_v, is_union_v)
	(is_class_v, is_function_v, is_reference_v, is_arithmetic_v)
	(is_fundamental_v, is_object_v, is_scalar_v, is_compound_v)
	(is_member_pointer_v, is_const_v, is_volatile_v, is_trivial_v)
	(is_trivially_copyable_v, is_standard_layout_v)
	(is_pod_v, is_literal_type_v, is_empty_v, is_polymorphic_v)
	(is_abstract_v, is_final_v, is_signed_v, is_unsigned_v)
	(is_constructible_v, is_default_constructible_v)
	(is_copy_constructible_v, is_move_constructible_v)
	(is_assignable_v, is_copy_assignable_v, is_move_assignable_v)
	(is_destructible_v, is_trivially_constructible_v)
	(is_trivially_default_constructible_v)
 	(is_trivially_copy_constructible_v, is_trivially_move_constructible_v)
	(is_trivially_assignable_v, is_trivially_copy_assignable_v)
	(is_trivially_move_assignable_v, is_trivially_destructible_v)
	(is_nothrow_constructible_v, is_nothrow_default_constructible_v)
	(is_nothrow_copy_constructible_v, is_nothrow_move_constructible_v)
	(is_nothrow_assignable_v, is_nothrow_copy_assignable_v)
	(is_nothrow_move_assignable_v, is_nothrow_destructible_v)
	(has_virtual_destructor_v, alignment_of_v, rank_v, extent_v)
	(is_same_v, is_base_of_v, is_convertible_v): Likewise.
	* testsuite/19_diagnostics/error_code/is_error_code_v.cc: Likewise.
	* testsuite/20_util/duration/requirements/treat_as_floating_point_v.cc:
	Likewise.
	* testsuite/20_util/ratio/requirements/ratio_equal_v.cc: Likewise.
	* testsuite/20_util/tuple/tuple_size_v.cc: Likewise.
	* testsuite/20_util/variable_templates_for_traits.cc: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@238892 138bc75d-0d04-0410-961f-82ee72b054a4

11 files changed, 739 insertions, 1 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 702c137cce4..40102865bce 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,45 @@
+2016-07-29  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	Implement C++17 variable templates for type traits.
+	* include/std/chrono (treat_as_floating_point_v): New.
+	* include/std/ratio (ratio_equal_v, ratio_not_equal_v)
+	(ratio_less_v, ratio_less_equal_v, ratio_greater_v)
+	(ratio_greater_equal_v): Likewise.
+	* include/std/system_error (is_error_code_enum_v)
+	(is_error_condition_enum_v): Likewise.
+	* include/std/tuple (tuple_size_v): Likewise.
+	* type_traits (conjunction_v, disjunction_v, negation_v)
+	(is_void_v, is_null_pointer_v, is_integral_v, is_floating_point_v)
+	(is_array_v, is_pointer_v, is_lvalue_reference_v)
+	(is_rvalue_reference_v, is_member_object_pointer_v)
+	(is_member_function_pointer_v, is_enum_v, is_union_v)
+	(is_class_v, is_function_v, is_reference_v, is_arithmetic_v)
+	(is_fundamental_v, is_object_v, is_scalar_v, is_compound_v)
+	(is_member_pointer_v, is_const_v, is_volatile_v, is_trivial_v)
+	(is_trivially_copyable_v, is_standard_layout_v)
+	(is_pod_v, is_literal_type_v, is_empty_v, is_polymorphic_v)
+	(is_abstract_v, is_final_v, is_signed_v, is_unsigned_v)
+	(is_constructible_v, is_default_constructible_v)
+	(is_copy_constructible_v, is_move_constructible_v)
+	(is_assignable_v, is_copy_assignable_v, is_move_assignable_v)
+	(is_destructible_v, is_trivially_constructible_v)
+	(is_trivially_default_constructible_v)
+ 	(is_trivially_copy_constructible_v, is_trivially_move_constructible_v)
+	(is_trivially_assignable_v, is_trivially_copy_assignable_v)
+	(is_trivially_move_assignable_v, is_trivially_destructible_v)
+	(is_nothrow_constructible_v, is_nothrow_default_constructible_v)
+	(is_nothrow_copy_constructible_v, is_nothrow_move_constructible_v)
+	(is_nothrow_assignable_v, is_nothrow_copy_assignable_v)
+	(is_nothrow_move_assignable_v, is_nothrow_destructible_v)
+	(has_virtual_destructor_v, alignment_of_v, rank_v, extent_v)
+	(is_same_v, is_base_of_v, is_convertible_v): Likewise.
+	* testsuite/19_diagnostics/error_code/is_error_code_v.cc: Likewise.
+	* testsuite/20_util/duration/requirements/treat_as_floating_point_v.cc:
+	Likewise.
+	* testsuite/20_util/ratio/requirements/ratio_equal_v.cc: Likewise.
+	* testsuite/20_util/tuple/tuple_size_v.cc: Likewise.
+	* testsuite/20_util/variable_templates_for_traits.cc: Likewise.
+
 2016-07-29  Andreas Schwab  <schwab@linux-m68k.org>
 
 	* config/abi/post/aarch64-linux-gnu/baseline_symbols.txt: Update.
diff --git a/libstdc++-v3/include/std/chrono b/libstdc++-v3/include/std/chrono
index 9104881eb93..fdb21b34d43 100644
--- a/libstdc++-v3/include/std/chrono
+++ b/libstdc++-v3/include/std/chrono
@@ -208,7 +208,11 @@ _GLIBCXX_END_NAMESPACE_VERSION
       struct treat_as_floating_point
       : is_floating_point<_Rep>
       { };
-
+#if __cplusplus > 201402L
+    template <typename _Rep>
+      constexpr bool treat_as_floating_point_v =
+        treat_as_floating_point<_Rep>::value;
+#endif // C++17
     /// duration_values
     template<typename _Rep>
       struct duration_values
diff --git a/libstdc++-v3/include/std/ratio b/libstdc++-v3/include/std/ratio
index 9d7b61cd840..4a243a0cf73 100644
--- a/libstdc++-v3/include/std/ratio
+++ b/libstdc++-v3/include/std/ratio
@@ -401,6 +401,22 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     : integral_constant<bool, !ratio_less<_R1, _R2>::value>
     { };
 
+#if __cplusplus > 201402L
+  template <typename _R1, typename _R2>
+    constexpr bool ratio_equal_v = ratio_equal<_R1, _R2>::value;
+  template <typename _R1, typename _R2>
+    constexpr bool ratio_not_equal_v = ratio_not_equal<_R1, _R2>::value;
+  template <typename _R1, typename _R2>
+    constexpr bool ratio_less_v = ratio_less<_R1, _R2>::value;
+  template <typename _R1, typename _R2>
+    constexpr bool ratio_less_equal_v = ratio_less_equal<_R1, _R2>::value;
+  template <typename _R1, typename _R2>
+    constexpr bool ratio_greater_v = ratio_greater<_R1, _R2>::value;
+  template <typename _R1, typename _R2>
+    constexpr bool ratio_greater_equal_v
+    = ratio_greater_equal<_R1, _R2>::value;
+#endif // C++17
+
   template<typename _R1, typename _R2,
       bool = (_R1::num >= 0),
       bool = (_R2::num >= 0),
diff --git a/libstdc++-v3/include/std/system_error b/libstdc++-v3/include/std/system_error
index 79320fac598..1ef64f46015 100644
--- a/libstdc++-v3/include/std/system_error
+++ b/libstdc++-v3/include/std/system_error
@@ -60,6 +60,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     struct is_error_condition_enum<errc>
     : public true_type { };
 
+#if __cplusplus > 201402L
+  template <typename _Tp>
+    constexpr bool is_error_code_enum_v = is_error_code_enum<_Tp>::value;
+  template <typename _Tp>
+    constexpr bool is_error_condition_enum_v =
+      is_error_condition_enum<_Tp>::value;
+#endif // C++17
   inline namespace _V2 {
 
   /// error_category
diff --git a/libstdc++-v3/include/std/tuple b/libstdc++-v3/include/std/tuple
index 180a34629f8..c1c924c1212 100644
--- a/libstdc++-v3/include/std/tuple
+++ b/libstdc++-v3/include/std/tuple
@@ -1265,6 +1265,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     struct tuple_size<tuple<_Elements...>>
     : public integral_constant<std::size_t, sizeof...(_Elements)> { };
 
+#if __cplusplus > 201402L
+  template <typename _Tp>
+    constexpr size_t tuple_size_v = tuple_size<_Tp>::value;
+#endif
+
   template<std::size_t __i, typename _Head, typename... _Tail>
     constexpr _Head&
     __get_helper(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index e5c0d468f92..bfdc3ba90cf 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -172,6 +172,19 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     struct negation
     : __not_<_Pp>
     { };
+
+  template<typename... _Bn>
+    constexpr bool conjunction_v
+    = conjunction<_Bn...>::value;
+  
+  template<typename... _Bn>
+    constexpr bool disjunction_v
+    = disjunction<_Bn...>::value;
+  
+  template<typename _Pp>
+    constexpr bool negation_v
+    = negation<_Pp>::value;
+
 #endif
 
   // For several sfinae-friendly trait implementations we transport both the
@@ -2765,6 +2778,159 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     constexpr bool is_nothrow_swappable_with_v =
       is_nothrow_swappable_with<_Tp, _Up>::value;
 #endif // __cplusplus >= 201402L
+
+#if __cplusplus > 201402L
+template <typename _Tp>
+  constexpr bool is_void_v = is_void<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_null_pointer_v = is_null_pointer<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_integral_v = is_integral<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_floating_point_v = is_floating_point<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_array_v = is_array<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_pointer_v = is_pointer<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_lvalue_reference_v = is_lvalue_reference<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_rvalue_reference_v = is_rvalue_reference<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_member_object_pointer_v =
+    is_member_object_pointer<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_member_function_pointer_v =
+    is_member_function_pointer<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_enum_v = is_enum<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_union_v = is_union<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_class_v = is_class<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_function_v = is_function<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_reference_v = is_reference<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_fundamental_v = is_fundamental<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_object_v = is_object<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_scalar_v = is_scalar<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_compound_v = is_compound<_Tp>::value;
+template <typename _Tp>
+ constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_const_v = is_const<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_volatile_v = is_volatile<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_trivial_v = is_trivial<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_trivially_copyable_v = is_trivially_copyable<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_standard_layout_v = is_standard_layout<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_pod_v = is_pod<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_literal_type_v = is_literal_type<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_empty_v = is_empty<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_polymorphic_v = is_polymorphic<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_abstract_v = is_abstract<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_final_v = is_final<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_signed_v = is_signed<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_unsigned_v = is_unsigned<_Tp>::value;
+template <typename _Tp, typename... _Args>
+  constexpr bool is_constructible_v = is_constructible<_Tp, _Args...>::value;
+template <typename _Tp>
+  constexpr bool is_default_constructible_v =
+    is_default_constructible<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_copy_constructible_v = is_copy_constructible<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_move_constructible_v = is_move_constructible<_Tp>::value;
+template <typename _Tp, typename _Up>
+  constexpr bool is_assignable_v = is_assignable<_Tp, _Up>::value;
+template <typename _Tp>
+  constexpr bool is_copy_assignable_v = is_copy_assignable<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_move_assignable_v = is_move_assignable<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_destructible_v = is_destructible<_Tp>::value;
+template <typename _Tp, typename... _Args>
+  constexpr bool is_trivially_constructible_v =
+    is_trivially_constructible<_Tp, _Args...>::value;
+template <typename _Tp>
+  constexpr bool is_trivially_default_constructible_v =
+    is_trivially_default_constructible<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_trivially_copy_constructible_v =
+    is_trivially_copy_constructible<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_trivially_move_constructible_v =
+    is_trivially_move_constructible<_Tp>::value;
+template <typename _Tp, typename _Up>
+  constexpr bool is_trivially_assignable_v =
+    is_trivially_assignable<_Tp, _Up>::value;
+template <typename _Tp>
+  constexpr bool is_trivially_copy_assignable_v =
+    is_trivially_copy_assignable<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_trivially_move_assignable_v =
+    is_trivially_move_assignable<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_trivially_destructible_v =
+    is_trivially_destructible<_Tp>::value;
+template <typename _Tp, typename... _Args>
+  constexpr bool is_nothrow_constructible_v =
+    is_nothrow_constructible<_Tp, _Args...>::value;
+template <typename _Tp>
+  constexpr bool is_nothrow_default_constructible_v =
+    is_nothrow_default_constructible<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_nothrow_copy_constructible_v =
+    is_nothrow_copy_constructible<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_nothrow_move_constructible_v =
+    is_nothrow_move_constructible<_Tp>::value;
+template <typename _Tp, typename _Up>
+  constexpr bool is_nothrow_assignable_v =
+    is_nothrow_assignable<_Tp, _Up>::value;
+template <typename _Tp>
+  constexpr bool is_nothrow_copy_assignable_v =
+    is_nothrow_copy_assignable<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_nothrow_move_assignable_v =
+    is_nothrow_move_assignable<_Tp>::value;
+template <typename _Tp>
+  constexpr bool is_nothrow_destructible_v =
+    is_nothrow_destructible<_Tp>::value;
+template <typename _Tp>
+  constexpr bool has_virtual_destructor_v =
+    has_virtual_destructor<_Tp>::value;
+template <typename _Tp>
+  constexpr size_t alignment_of_v = alignment_of<_Tp>::value;
+template <typename _Tp>
+  constexpr size_t rank_v = rank<_Tp>::value;
+template <typename _Tp, unsigned _Idx = 0>
+  constexpr size_t extent_v = extent<_Tp, _Idx>::value;
+template <typename _Tp, typename _Up>
+  constexpr bool is_same_v = is_same<_Tp, _Up>::value;
+template <typename _Base, typename _Derived>
+  constexpr bool is_base_of_v = is_base_of<_Base, _Derived>::value;
+template <typename _From, typename _To>
+  constexpr bool is_convertible_v = is_convertible<_From, _To>::value;
+#endif // C++17
 #endif
 
 _GLIBCXX_END_NAMESPACE_VERSION
diff --git a/libstdc++-v3/testsuite/19_diagnostics/error_code/is_error_code_v.cc b/libstdc++-v3/testsuite/19_diagnostics/error_code/is_error_code_v.cc
new file mode 100644
index 00000000000..629cae1fcf8
--- /dev/null
+++ b/libstdc++-v3/testsuite/19_diagnostics/error_code/is_error_code_v.cc
@@ -0,0 +1,39 @@
+// { dg-options "-std=gnu++17" }
+// { dg-do compile }
+
+// Copyright (C) 2014-2016 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a moved_to of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <system_error>
+#include <future>
+using namespace std;
+
+// These tests are rather simple, the front-end tests already test
+// variable templates, and the library tests for the underlying
+// traits are more elaborate. These are just simple sanity tests.
+
+static_assert(is_error_code_enum_v<future_errc>
+	      && is_error_code_enum<future_errc>::value, "");
+
+static_assert(!is_error_code_enum_v<int>
+	      && !is_error_code_enum<int>::value, "");
+
+static_assert(is_error_condition_enum_v<errc>
+	      && is_error_condition_enum<errc>::value, "");
+
+static_assert(!is_error_condition_enum_v<int>
+	      && !is_error_condition_enum<int>::value, "");
diff --git a/libstdc++-v3/testsuite/20_util/duration/requirements/treat_as_floating_point_v.cc b/libstdc++-v3/testsuite/20_util/duration/requirements/treat_as_floating_point_v.cc
new file mode 100644
index 00000000000..0148239f5e0
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/duration/requirements/treat_as_floating_point_v.cc
@@ -0,0 +1,33 @@
+// { dg-options "-std=gnu++17" }
+// { dg-do compile }
+
+// Copyright (C) 2014-2016 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a moved_to of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <chrono>
+
+using namespace std::chrono;
+
+// These tests are rather simple, the front-end tests already test
+// variable templates, and the library tests for the underlying
+// traits are more elaborate. These are just simple sanity tests.
+
+static_assert(!treat_as_floating_point_v<int>
+	      && !treat_as_floating_point<int>::value, "");
+
+static_assert(treat_as_floating_point_v<double>
+	      && treat_as_floating_point<double>::value, "");
diff --git a/libstdc++-v3/testsuite/20_util/ratio/requirements/ratio_equal_v.cc b/libstdc++-v3/testsuite/20_util/ratio/requirements/ratio_equal_v.cc
new file mode 100644
index 00000000000..1158a67dd39
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/ratio/requirements/ratio_equal_v.cc
@@ -0,0 +1,49 @@
+// { dg-options "-std=gnu++17" }
+// { dg-do compile }
+
+// Copyright (C) 2014-2016 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a moved_to of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <ratio>
+
+using namespace std;
+
+// These tests are rather simple, the front-end tests already test
+// variable templates, and the library tests for the underlying
+// traits are more elaborate. These are just simple sanity tests.
+
+static_assert(ratio_equal_v<ratio<1, 3>, ratio<2, 6>>
+	      && ratio_equal<ratio<1, 3>, ratio<2, 6>>::value, "");
+
+static_assert(ratio_not_equal_v<ratio<1, 3>, ratio<2, 5>>
+	      && ratio_not_equal<ratio<1, 3>, ratio<2, 5>>::value, "");
+
+static_assert(ratio_less_v<ratio<1, 4>, ratio<1, 3>>
+	      && ratio_less<ratio<1, 4>, ratio<1, 3>>::value, "");
+
+static_assert(ratio_less_equal_v<ratio<1, 4>, ratio<1, 4>>
+	      && ratio_less_equal_v<ratio<1, 4>, ratio<1, 3>>
+	      && ratio_less_equal<ratio<1, 4>, ratio<1, 4>>::value
+	      && ratio_less_equal<ratio<1, 4>, ratio<1, 3>>::value, "");
+
+static_assert(ratio_greater_v<ratio<1, 3>, ratio<1, 4>>
+	      && ratio_greater<ratio<1, 3>, ratio<1, 4>>::value, "");
+
+static_assert(ratio_greater_equal_v<ratio<1, 4>, ratio<1, 4>>
+	      && ratio_greater_equal_v<ratio<1, 3>, ratio<1, 4>>
+	      && ratio_greater_equal<ratio<1, 4>, ratio<1, 4>>::value
+	      && ratio_greater_equal<ratio<1, 3>, ratio<1, 4>>::value, "");
diff --git a/libstdc++-v3/testsuite/20_util/tuple/tuple_size_v.cc b/libstdc++-v3/testsuite/20_util/tuple/tuple_size_v.cc
new file mode 100644
index 00000000000..29ce5c1701f
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/tuple/tuple_size_v.cc
@@ -0,0 +1,33 @@
+// { dg-options "-std=gnu++17" }
+// { dg-do compile }
+
+// Copyright (C) 2014-2016 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a moved_to of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <tuple>
+
+using namespace std;
+
+// These tests are rather simple, the front-end tests already test
+// variable templates, and the library tests for the underlying
+// traits are more elaborate. These are just simple sanity tests.
+
+static_assert(tuple_size_v<tuple<int>> == 1
+	      && tuple_size<tuple<int>>::value == 1, "");
+
+static_assert(tuple_size_v<tuple<int, int>> == 2
+	      && tuple_size<tuple<int, int>>::value == 2, "");
diff --git a/libstdc++-v3/testsuite/20_util/variable_templates_for_traits.cc b/libstdc++-v3/testsuite/20_util/variable_templates_for_traits.cc
new file mode 100644
index 00000000000..5a497f12445
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/variable_templates_for_traits.cc
@@ -0,0 +1,344 @@
+// { dg-options "-std=gnu++17" }
+// { dg-do compile }
+
+// Copyright (C) 2014-2016 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a moved_to of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <type_traits>
+
+using namespace std;
+
+// These tests are rather simple, the front-end tests already test
+// variable templates, and the library tests for the underlying
+// traits are more elaborate. These are just simple sanity tests.
+
+static_assert(is_void_v<void> && is_void<void>::value, "");
+static_assert(!is_void_v<int> && !is_void<int>::value, "");
+
+static_assert(is_null_pointer_v<nullptr_t>
+	      && is_null_pointer<nullptr_t>::value, "");
+static_assert(!is_null_pointer_v<void*>
+	      && !is_null_pointer<void*>::value, "");
+
+static_assert(is_integral_v<int> && is_integral<int>::value, "");
+static_assert(!is_integral_v<int*> && !is_integral<int*>::value, "");
+
+static_assert(is_floating_point_v<float>
+	      && is_floating_point<float>::value, "");
+static_assert(!is_floating_point_v<int>
+	      && !is_floating_point<int>::value, "");
+
+static_assert(is_array_v<char[42]> && is_array<char[42]>::value, "");
+static_assert(!is_array_v<char*> && !is_array<char*>::value, "");
+
+static_assert(is_pointer_v<int*> && is_pointer<int*>::value, "");
+static_assert(!is_pointer_v<int> && !is_pointer<int>::value, "");
+
+static_assert(is_lvalue_reference_v<int&>
+	      && is_lvalue_reference<int&>::value, "");
+static_assert(!is_lvalue_reference_v<int>
+	      && !is_lvalue_reference<int>::value, "");
+
+static_assert(is_rvalue_reference_v<int&&>
+	      && is_rvalue_reference<int&&>::value, "");
+static_assert(!is_rvalue_reference_v<int>
+	      && !is_rvalue_reference<int>::value, "");
+
+struct EmptyFinal final {};
+
+static_assert(is_member_object_pointer_v<int (EmptyFinal::*)>
+	      && is_member_object_pointer<int (EmptyFinal::*)>::value, "");
+static_assert(!is_member_object_pointer_v<void*>
+	      && !is_member_object_pointer<void*>::value, "");
+
+static_assert(is_member_function_pointer_v<int (EmptyFinal::*)()>
+	      && is_member_function_pointer<int (EmptyFinal::*)()>::value, "");
+static_assert(!is_member_function_pointer_v<void*>
+	      && !is_member_function_pointer<void*>::value, "");
+
+enum Enum {};
+
+static_assert(is_enum_v<Enum> && is_enum<Enum>::value, "");
+static_assert(!is_enum_v<int> && !is_enum<int>::value, "");
+
+union Union;
+
+static_assert(is_union_v<Union> && is_union<Union>::value, "");
+static_assert(!is_union_v<int> && !is_union<int>::value, "");
+
+static_assert(is_class_v<EmptyFinal> && is_class<EmptyFinal>::value, "");
+static_assert(!is_class_v<int> && !is_class<int>::value, "");
+
+static_assert(is_function_v<void()> && is_function<void()>::value, "");
+static_assert(!is_function_v<void(*)()> && !is_function<void(*)()>::value, "");
+
+static_assert(is_reference_v<int&> && is_reference<int&>::value, "");
+static_assert(!is_reference_v<int> && !is_reference<int>::value, "");
+
+static_assert(is_arithmetic_v<int> && is_arithmetic<int>::value, "");
+static_assert(!is_arithmetic_v<void*> && !is_arithmetic<void*>::value, "");
+
+static_assert(is_fundamental_v<int> && is_fundamental<int>::value, "");
+static_assert(!is_fundamental_v<EmptyFinal>
+	      && !is_fundamental<EmptyFinal>::value, "");
+
+static_assert(is_object_v<int> && is_object<int>::value, "");
+static_assert(!is_object_v<int&> && !is_object<int&>::value, "");
+
+static_assert(is_scalar_v<int> && is_scalar<int>::value, "");
+static_assert(!is_scalar_v<int&> && !is_scalar<int&>::value, "");
+
+static_assert(is_compound_v<EmptyFinal>
+	      && is_compound<EmptyFinal>::value, "");
+static_assert(!is_compound_v<int> && !is_compound<int>::value, "");
+
+static_assert(is_member_pointer_v<int (EmptyFinal::*)>
+	      && is_member_pointer<int (EmptyFinal::*)>::value, "");
+static_assert(!is_member_pointer_v<void*>
+	      && !is_member_pointer<void*>::value, "");
+
+static_assert(is_const_v<const int> && is_const<const int>::value, "");
+static_assert(!is_const_v<int> && !is_const<int>::value, "");
+
+static_assert(is_volatile_v<volatile int>
+	      && is_volatile<volatile int>::value, "");
+static_assert(!is_volatile_v<int> && !is_volatile<int>::value, "");
+
+struct NType
+{
+  NType(int);
+  ~NType();
+  int i;
+private:
+  NType(const NType&);
+  NType& operator=(const NType&);
+  int i2;
+};
+
+static_assert(is_trivial_v<int> && is_trivial<int>::value, "");
+static_assert(!is_trivial_v<NType> && !is_trivial<NType>::value, "");
+
+static_assert(is_trivially_copyable_v<int>
+	      && is_trivially_copyable<int>::value, "");
+static_assert(!is_trivially_copyable_v<NType>
+	      && !is_trivially_copyable<NType>::value, "");
+
+static_assert(is_standard_layout_v<int>
+	      && is_standard_layout<int>::value, "");
+static_assert(!is_standard_layout_v<NType>
+	      && !is_standard_layout<NType>::value, "");
+
+static_assert(is_pod_v<int>
+	      && is_pod<int>::value, "");
+static_assert(!is_pod_v<NType>
+	      && !is_pod<NType>::value, "");
+
+static_assert(is_literal_type_v<int>
+	      && is_literal_type<int>::value, "");
+static_assert(!is_literal_type_v<NType>
+	      && !is_literal_type<NType>::value, "");
+
+static_assert(is_empty_v<EmptyFinal>
+	      && is_empty<EmptyFinal>::value, "");
+static_assert(!is_empty_v<NType>
+	      && !is_empty<NType>::value, "");
+
+struct Abstract {protected: virtual ~Abstract() = 0;};
+struct Poly : Abstract {virtual ~Poly();};
+
+static_assert(is_polymorphic_v<Poly>
+	      && is_polymorphic<Poly>::value, "");
+static_assert(!is_polymorphic_v<EmptyFinal>
+	      && !is_polymorphic<EmptyFinal>::value, "");
+
+
+
+static_assert(is_abstract_v<Abstract>
+	      && is_abstract<Abstract>::value, "");
+static_assert(!is_abstract_v<EmptyFinal>
+	      && !is_abstract<EmptyFinal>::value, "");
+
+static_assert(is_final_v<EmptyFinal>
+	      && is_final<EmptyFinal>::value, "");
+static_assert(!is_final_v<Abstract>
+	      && !is_final<Abstract>::value, "");
+
+static_assert(is_signed_v<int> && is_signed<int>::value, "");
+static_assert(!is_signed_v<unsigned int>
+	      && !is_signed<unsigned int>::value, "");
+
+static_assert(is_constructible_v<int, int>
+	      && is_constructible<int, int>::value, "");
+static_assert(!is_constructible_v<int, void*>
+	      && !is_constructible<int, void*>::value, "");
+
+static_assert(is_default_constructible_v<int>
+	      && is_default_constructible<int>::value, "");
+static_assert(!is_default_constructible_v<NType>
+	      && !is_default_constructible<NType>::value, "");
+
+static_assert(is_copy_constructible_v<int>
+	      && is_copy_constructible<int>::value, "");
+static_assert(!is_copy_constructible_v<NType>
+	      && !is_copy_constructible<NType>::value, "");
+
+static_assert(is_move_constructible_v<int>
+	      && is_copy_constructible<int>::value, "");
+static_assert(!is_move_constructible_v<NType>
+	      && !is_copy_constructible<NType>::value, "");
+
+static_assert(is_assignable_v<int&, int>
+	      && is_assignable<int&, int>::value, "");
+static_assert(!is_assignable_v<int, int>
+	      && !is_assignable<int, int>::value, "");
+
+static_assert(is_copy_assignable_v<int>
+	      && is_copy_assignable<int>::value, "");
+static_assert(!is_copy_assignable_v<NType>
+	      && !is_copy_assignable<NType>::value, "");
+
+static_assert(is_move_assignable_v<int>
+	      && is_move_assignable<int>::value, "");
+static_assert(!is_move_assignable_v<NType>
+	      && !is_move_assignable<NType>::value, "");
+
+static_assert(is_destructible_v<int>
+	      && is_destructible<int>::value, "");
+static_assert(!is_destructible_v<Abstract>
+	      && !is_destructible<Abstract>::value, "");
+
+static_assert(is_trivially_constructible_v<int, int>
+	      && is_trivially_constructible<int, int>::value, "");
+static_assert(!is_trivially_constructible_v<NType, NType>
+	      && !is_trivially_constructible<NType, NType>::value, "");
+
+static_assert(is_trivially_default_constructible_v<int>
+	      && is_trivially_default_constructible<int>::value, "");
+static_assert(!is_trivially_default_constructible_v<NType>
+	      && !is_trivially_default_constructible<NType>::value, "");
+
+static_assert(is_trivially_copy_constructible_v<int>
+	      && is_trivially_copy_constructible<int>::value, "");
+static_assert(!is_trivially_copy_constructible_v<NType>
+	      && !is_trivially_copy_constructible<NType>::value, "");
+
+static_assert(is_trivially_move_constructible_v<int>
+	      && is_trivially_move_constructible<int>::value, "");
+static_assert(!is_trivially_move_constructible_v<NType>
+	      && !is_trivially_move_constructible<NType>::value, "");
+
+static_assert(is_trivially_assignable_v<int&, int>
+	      && is_trivially_assignable<int&, int>::value, "");
+static_assert(!is_trivially_assignable_v<NType, NType>
+	      && !is_trivially_assignable<NType, NType>::value, "");
+
+static_assert(is_trivially_copy_assignable_v<int>
+	      && is_trivially_copy_assignable<int>::value, "");
+static_assert(!is_trivially_copy_assignable_v<NType>
+	      && !is_trivially_copy_assignable<NType>::value, "");
+
+static_assert(is_trivially_move_assignable_v<int>
+	      && is_trivially_move_assignable<int>::value, "");
+static_assert(!is_trivially_move_assignable_v<NType>
+	      && !is_trivially_move_assignable<NType>::value, "");
+
+static_assert(is_trivially_destructible_v<int>
+	      && is_trivially_destructible<int>::value, "");
+static_assert(!is_trivially_destructible_v<Abstract>
+	      && !is_trivially_destructible<Abstract>::value, "");
+
+static_assert(is_nothrow_constructible_v<int, int>
+	      && is_nothrow_constructible<int, int>::value, "");
+static_assert(!is_nothrow_constructible_v<NType, NType>
+	      && !is_nothrow_constructible<NType, NType>::value, "");
+
+static_assert(is_nothrow_default_constructible_v<int>
+	      && is_nothrow_default_constructible<int>::value, "");
+static_assert(!is_nothrow_default_constructible_v<NType>
+	      && !is_nothrow_default_constructible<NType>::value, "");
+
+static_assert(is_nothrow_copy_constructible_v<int>
+	      && is_nothrow_copy_constructible<int>::value, "");
+static_assert(!is_nothrow_copy_constructible_v<NType>
+	      && !is_nothrow_copy_constructible<NType>::value, "");
+
+static_assert(is_nothrow_move_constructible_v<int>
+	      && is_nothrow_move_constructible<int>::value, "");
+static_assert(!is_nothrow_move_constructible_v<NType>
+	      && !is_nothrow_move_constructible<NType>::value, "");
+
+static_assert(is_nothrow_assignable_v<int&, int>
+	      && is_nothrow_assignable<int&, int>::value, "");
+static_assert(!is_nothrow_assignable_v<NType, NType>
+	      && !is_nothrow_assignable<NType, NType>::value, "");
+
+static_assert(is_nothrow_copy_assignable_v<int>
+	      && is_nothrow_copy_assignable<int>::value, "");
+static_assert(!is_nothrow_copy_assignable_v<NType>
+	      && !is_nothrow_copy_assignable<NType>::value, "");
+
+static_assert(is_nothrow_move_assignable_v<int>
+	      && is_nothrow_move_assignable<int>::value, "");
+static_assert(!is_nothrow_move_assignable_v<NType>
+	      && !is_nothrow_move_assignable<NType>::value, "");
+
+static_assert(has_virtual_destructor_v<Abstract>
+	      && has_virtual_destructor<Abstract>::value, "");
+static_assert(!has_virtual_destructor_v<NType>
+	      && !has_virtual_destructor<NType>::value, "");
+
+static_assert(alignment_of_v<int> == alignof(int)
+	      && alignment_of<int>::value == alignof(int) , "");
+
+static_assert(rank_v<int[1][1]> == rank<int[1][1]>::value, "");
+
+static_assert(extent_v<int[1][2], 1> == 2
+	      && extent<int[1][2], 1>::value == 2, "");
+
+static_assert(is_same_v<int, int> && is_same<int, int>::value, "");
+static_assert(!is_same_v<int, char> && !is_same<int, char>::value, "");
+
+static_assert(is_base_of_v<Abstract, Poly>
+	      && is_base_of<Abstract, Poly>::value, "");
+static_assert(!is_base_of_v<Abstract, NType>
+	      && !is_base_of<Abstract, NType>::value, "");
+
+static_assert(is_convertible_v<int&, const int&>
+	      && is_convertible<int&, const int&>::value, "");
+static_assert(!is_convertible_v<const int&, int&>
+	      && !is_convertible<const int&, int&>::value, "");
+
+static_assert(negation_v<false_type>, "");
+static_assert(!negation_v<true_type>, "");
+static_assert(conjunction_v<>, "");
+static_assert(!disjunction_v<>, "");
+static_assert(conjunction_v<true_type>, "");
+static_assert(!conjunction_v<false_type>, "");
+static_assert(disjunction_v<true_type>, "");
+static_assert(!disjunction_v<false_type>, "");
+static_assert(conjunction_v<true_type, true_type>, "");
+static_assert(!conjunction_v<true_type, false_type>, "");
+static_assert(disjunction_v<false_type, true_type>, "");
+static_assert(!disjunction_v<false_type, false_type>, "");
+static_assert(conjunction_v<true_type, true_type,
+              true_type>, "");
+static_assert(!conjunction_v<true_type, true_type,
+              false_type>, "");
+static_assert(disjunction_v<false_type, false_type,
+              true_type>, "");
+static_assert(!disjunction_v<false_type, false_type,
+              false_type>, "");