Implement new C++ intrinsics __is_assignable and __is_constructible.

c-family/

Implement new C++ intrinsics __is_assignable and __is_constructible.
* c-common.c (__is_assignable, __is_constructible): New.
* c-common.h (RID_IS_ASSIGNABLE, RID_IS_CONSTRUCTIBLE): Likewise.

cp/

PR c++/80654
PR c++/80682
Implement new C++ intrinsics __is_assignable and __is_constructible.
* cp-tree.h (CPTK_IS_ASSIGNABLE, CPTK_IS_CONSTRUCTIBLE): New.
(is_xible): New.
* cxx-pretty-print.c (pp_cxx_trait_expression): Handle
CPTK_IS_ASSIGNABLE and CPTK_IS_CONSTRUCTIBLE.
* method.c (constructible_expr): Set cp_unevaluated.
(is_xible_helper): New.
(is_trivially_xible): Adjust.
(is_xible): New.
* parser.c (cp_parser_primary_expression): Handle
RID_IS_ASSIGNABLE and RID_IS_CONSTRUCTIBLE.
(cp_parser_trait_expr): Likewise.
* semantics.c (trait_expr_value): Handle
CPTK_IS_ASSIGNABLE and CPTK_IS_CONSTRUCTIBLE.

testsuite/

* g++.dg/ext/80654.C: New.

libstdc++-v3/

Implement new C++ intrinsics __is_assignable and __is_constructible.
* include/std/type_traits (__do_is_static_castable_impl): Remove.
(__is_static_castable_impl, __is_static_castable_safe): Likewise.
(__is_static_castable, __do_is_direct_constructible_impl): Likewise.
(__is_direct_constructible_impl): Likewise.
(__is_direct_constructible_new_safe): Likewise.
(__is_base_to_derived_ref, __is_lvalue_to_rvalue_ref): Likewise.
(__is_direct_constructible_ref_cast): Likewise.
(__is_direct_constructible_new, __is_direct_constructible): Likewise.
(__do_is_nary_constructible_impl): Likewise.
(__is_nary_constructible_impl, __is_nary_constructible): Likewise.
(__is_constructible_impl): Likewise.
(is_constructible): Call the intrinsic.
(__is_assignable_helper): Remove.
(is_assignable): Call the intrinsic.
(is_trivially_constructible): Likewise.
(__is_trivially_copy_constructible_impl): New.
(is_trivially_copy_constructible): Use it.
(__is_trivially_move_constructible_impl): New.
(is_trivially_move_constructible): Use it.
(is_trivially_assignable): Call the intrinsic.
(__is_trivially_copy_assignable_impl): New.
(is_trivially_copy_assignable): Use it.
(__is_trivially_move_assignable_impl): New.
(is_trivially_move_assignable): Use it.
(testsuite/20_util/declval/requirements/1_neg.cc): Adjust.
(testsuite/20_util/is_trivially_copy_assignable/value.cc):
Add test for void.
(testsuite/20_util/is_trivially_copy_constructible/value.cc): Likewise.
(testsuite/20_util/is_trivially_move_assignable/value.cc): Likewise.
(testsuite/20_util/is_trivially_move_constructible/value.cc): Likewise.
(testsuite/20_util/make_signed/requirements/typedefs_neg.cc): Adjust.
(testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc):
Likewise.

From-SVN: r248153

19 files changed, 220 insertions, 242 deletions

diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 4b1c226..428d733 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,9 @@
+2017-05-17  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	Implement new C++ intrinsics __is_assignable and __is_constructible.
+	* c-common.c (__is_assignable, __is_constructible): New.
+	* c-common.h (RID_IS_ASSIGNABLE, RID_IS_CONSTRUCTIBLE): Likewise.
+
 2017-05-17  Martin Liska  <mliska@suse.cz>
 
 	* c-common.h: Introduce dump_flags_t type and
diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
index f606e94..a3c63d7 100644
--- a/gcc/c-family/c-common.c
+++ b/gcc/c-family/c-common.c
@@ -514,6 +514,8 @@ const struct c_common_resword c_common_reswords[] =
   { "volatile",		RID_VOLATILE,	0 },
   { "wchar_t",		RID_WCHAR,	D_CXXONLY },
   { "while",		RID_WHILE,	0 },
+  { "__is_assignable", RID_IS_ASSIGNABLE, D_CXXONLY },
+  { "__is_constructible", RID_IS_CONSTRUCTIBLE, D_CXXONLY },
 
   /* C++ transactional memory.  */
   { "synchronized",	RID_SYNCHRONIZED, D_CXX_OBJC | D_TRANSMEM },
diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index 5ce3b45..3023b07 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -172,6 +172,7 @@ enum rid
   RID_IS_TRIVIALLY_ASSIGNABLE, RID_IS_TRIVIALLY_CONSTRUCTIBLE,
   RID_IS_TRIVIALLY_COPYABLE,
   RID_IS_UNION,                RID_UNDERLYING_TYPE,
+  RID_IS_ASSIGNABLE,           RID_IS_CONSTRUCTIBLE,
 
   /* C++11 */
   RID_CONSTEXPR, RID_DECLTYPE, RID_NOEXCEPT, RID_NULLPTR, RID_STATIC_ASSERT,
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 7136b5d..f657194 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,22 @@
+2017-05-17  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	PR c++/80654
+	PR c++/80682
+	Implement new C++ intrinsics __is_assignable and __is_constructible.
+	* cp-tree.h (CPTK_IS_ASSIGNABLE, CPTK_IS_CONSTRUCTIBLE): New.
+	(is_xible): New.
+	* cxx-pretty-print.c (pp_cxx_trait_expression): Handle
+	CPTK_IS_ASSIGNABLE and CPTK_IS_CONSTRUCTIBLE.
+	* method.c (constructible_expr): Set cp_unevaluated.
+	(is_xible_helper): New.
+	(is_trivially_xible): Adjust.
+	(is_xible): New.
+	* parser.c (cp_parser_primary_expression): Handle
+	RID_IS_ASSIGNABLE and RID_IS_CONSTRUCTIBLE.
+	(cp_parser_trait_expr): Likewise.
+	* semantics.c (trait_expr_value): Handle
+	CPTK_IS_ASSIGNABLE and CPTK_IS_CONSTRUCTIBLE.
+
 2017-05-17  Nathan Sidwell  <nathan@acm.org>
 
 	* cp-tree.h (ovl_iterator::using_p): New predicate.
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 942ac61..9211186 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -1016,7 +1016,9 @@ enum cp_trait_kind
   CPTK_IS_TRIVIALLY_CONSTRUCTIBLE,
   CPTK_IS_TRIVIALLY_COPYABLE,
   CPTK_IS_UNION,
-  CPTK_UNDERLYING_TYPE
+  CPTK_UNDERLYING_TYPE,
+  CPTK_IS_ASSIGNABLE,
+  CPTK_IS_CONSTRUCTIBLE
 };
 
 /* The types that we are processing.  */
@@ -6227,6 +6229,7 @@ extern void use_thunk				(tree, bool);
 extern bool trivial_fn_p			(tree);
 extern tree forward_parm			(tree);
 extern bool is_trivially_xible			(enum tree_code, tree, tree);
+extern bool is_xible				(enum tree_code, tree, tree);
 extern tree get_defaulted_eh_spec		(tree);
 extern tree unevaluated_noexcept_spec		(void);
 extern void after_nsdmi_defaulted_late_checks   (tree);
diff --git a/gcc/cp/cxx-pretty-print.c b/gcc/cp/cxx-pretty-print.c
index e92a72a..b74a56f 100644
--- a/gcc/cp/cxx-pretty-print.c
+++ b/gcc/cp/cxx-pretty-print.c
@@ -2634,6 +2634,12 @@ pp_cxx_trait_expression (cxx_pretty_printer *pp, tree t)
     case CPTK_IS_LITERAL_TYPE:
       pp_cxx_ws_string (pp, "__is_literal_type");
       break;
+    case CPTK_IS_ASSIGNABLE:
+      pp_cxx_ws_string (pp, "__is_assignable");
+      break;
+    case CPTK_IS_CONSTRUCTIBLE:
+      pp_cxx_ws_string (pp, "__is_constructible");
+      break;
 
     default:
       gcc_unreachable ();
diff --git a/gcc/cp/method.c b/gcc/cp/method.c
index 9898ff1..756b59d 100644
--- a/gcc/cp/method.c
+++ b/gcc/cp/method.c
@@ -1162,6 +1162,7 @@ constructible_expr (tree to, tree from)
     {
       tree ctype = to;
       vec<tree, va_gc> *args = NULL;
+      cp_unevaluated cp_uneval_guard;
       if (TREE_CODE (to) != REFERENCE_TYPE)
 	to = cp_build_reference_type (to, /*rval*/false);
       tree ob = build_stub_object (to);
@@ -1198,22 +1199,36 @@ constructible_expr (tree to, tree from)
   return expr;
 }
 
-/* Returns true iff TO is trivially assignable (if CODE is MODIFY_EXPR) or
+/* Returns a tree iff TO is assignable (if CODE is MODIFY_EXPR) or
    constructible (otherwise) from FROM, which is a single type for
    assignment or a list of types for construction.  */
 
-bool
-is_trivially_xible (enum tree_code code, tree to, tree from)
+static tree
+is_xible_helper (enum tree_code code, tree to, tree from, bool trivial)
 {
-  if (VOID_TYPE_P (to))
-    return false;
+  if (VOID_TYPE_P (to) || ABSTRACT_CLASS_TYPE_P (to)
+      || (from && FUNC_OR_METHOD_TYPE_P (from)
+	  && (TYPE_READONLY (from) || FUNCTION_REF_QUALIFIED (from))))
+    return error_mark_node;
   tree expr;
   if (code == MODIFY_EXPR)
     expr = assignable_expr (to, from);
-  else if (from && TREE_CHAIN (from))
-    return false; // only 0- and 1-argument ctors can be trivial
+  else if (trivial && from && TREE_CHAIN (from))
+    return error_mark_node; // only 0- and 1-argument ctors can be trivial
   else
     expr = constructible_expr (to, from);
+  return expr;
+}
+
+/* Returns true iff TO is trivially assignable (if CODE is MODIFY_EXPR) or
+   constructible (otherwise) from FROM, which is a single type for
+   assignment or a list of types for construction.  */
+
+bool
+is_trivially_xible (enum tree_code code, tree to, tree from)
+{
+  tree expr;
+  expr = is_xible_helper (code, to, from, /*trivial*/true);
 
   if (expr == error_mark_node)
     return false;
@@ -1221,6 +1236,19 @@ is_trivially_xible (enum tree_code code, tree to, tree from)
   return !nt;
 }
 
+/* Returns true iff TO is assignable (if CODE is MODIFY_EXPR) or
+   constructible (otherwise) from FROM, which is a single type for
+   assignment or a list of types for construction.  */
+
+bool
+is_xible (enum tree_code code, tree to, tree from)
+{
+  tree expr = is_xible_helper (code, to, from, /*trivial*/false);
+  if (expr == error_mark_node)
+    return false;
+  return !!expr;
+}
+
 /* Subroutine of synthesized_method_walk.  Update SPEC_P, TRIVIAL_P and
    DELETED_P or give an error message MSG with argument ARG.  */
 
diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index 7ba2075..7a87a5e 100644
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -5135,6 +5135,8 @@ cp_parser_primary_expression (cp_parser *parser,
 	case RID_IS_TRIVIALLY_CONSTRUCTIBLE:
 	case RID_IS_TRIVIALLY_COPYABLE:
 	case RID_IS_UNION:
+	case RID_IS_ASSIGNABLE:
+	case RID_IS_CONSTRUCTIBLE:
 	  return cp_parser_trait_expr (parser, token->keyword);
 
 	// C++ concepts
@@ -9686,6 +9688,14 @@ cp_parser_trait_expr (cp_parser* parser, enum rid keyword)
     case RID_DIRECT_BASES:
       kind = CPTK_DIRECT_BASES;
       break;
+    case RID_IS_ASSIGNABLE:
+      kind = CPTK_IS_ASSIGNABLE;
+      binary = true;
+      break;
+    case RID_IS_CONSTRUCTIBLE:
+      kind = CPTK_IS_CONSTRUCTIBLE;
+      variadic = true;
+      break;
     default:
       gcc_unreachable ();
     }
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index d3249fe..fa02b27 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -9211,6 +9211,12 @@ trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_UNION:
       return type_code1 == UNION_TYPE;
 
+    case CPTK_IS_ASSIGNABLE:
+      return is_xible (MODIFY_EXPR, type1, type2);
+
+    case CPTK_IS_CONSTRUCTIBLE:
+      return is_xible (INIT_EXPR, type1, type2);
+
     default:
       gcc_unreachable ();
       return false;
@@ -9284,6 +9290,10 @@ finish_trait_expr (cp_trait_kind kind, tree type1, tree type2)
 	return error_mark_node;
       break;
 
+    case CPTK_IS_ASSIGNABLE:
+    case CPTK_IS_CONSTRUCTIBLE:
+      break;
+
     case CPTK_IS_TRIVIALLY_ASSIGNABLE:
     case CPTK_IS_TRIVIALLY_CONSTRUCTIBLE:
       if (!check_trait_type (type1)
diff --git a/gcc/testsuite/g++.dg/ext/80654.C b/gcc/testsuite/g++.dg/ext/80654.C
new file mode 100644
index 0000000..8679613
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/80654.C
@@ -0,0 +1,18 @@
+// { dg-do compile { target c++11 } }
+
+template <class T> struct wrap 
+{
+  T t;
+  wrap(const wrap& other) : t(other.t) {}
+};
+
+struct nocopy {
+  nocopy (const nocopy&) = delete;
+};
+
+int main ()
+{
+  static_assert(!__is_trivially_constructible(wrap<nocopy>,
+					      const wrap<nocopy>&), "");
+  return 0;
+}
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index c32dc62..98d363a 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,40 @@
+2017-05-17  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	Implement new C++ intrinsics __is_assignable and __is_constructible.
+	* include/std/type_traits (__do_is_static_castable_impl): Remove.
+	(__is_static_castable_impl, __is_static_castable_safe): Likewise.
+	(__is_static_castable, __do_is_direct_constructible_impl): Likewise.
+	(__is_direct_constructible_impl): Likewise.
+	(__is_direct_constructible_new_safe): Likewise.
+	(__is_base_to_derived_ref, __is_lvalue_to_rvalue_ref): Likewise.
+	(__is_direct_constructible_ref_cast): Likewise.
+	(__is_direct_constructible_new, __is_direct_constructible): Likewise.
+	(__do_is_nary_constructible_impl): Likewise.
+	(__is_nary_constructible_impl, __is_nary_constructible): Likewise.
+	(__is_constructible_impl): Likewise.
+	(is_constructible): Call the intrinsic.
+	(__is_assignable_helper): Remove.
+	(is_assignable): Call the intrinsic.
+	(is_trivially_constructible): Likewise.
+	(__is_trivially_copy_constructible_impl): New.
+	(is_trivially_copy_constructible): Use it.
+	(__is_trivially_move_constructible_impl): New.
+	(is_trivially_move_constructible): Use it.
+	(is_trivially_assignable): Call the intrinsic.
+	(__is_trivially_copy_assignable_impl): New.
+	(is_trivially_copy_assignable): Use it.
+	(__is_trivially_move_assignable_impl): New.
+	(is_trivially_move_assignable): Use it.
+	(testsuite/20_util/declval/requirements/1_neg.cc): Adjust.
+	(testsuite/20_util/is_trivially_copy_assignable/value.cc):
+	Add test for void.
+	(testsuite/20_util/is_trivially_copy_constructible/value.cc): Likewise.
+	(testsuite/20_util/is_trivially_move_assignable/value.cc): Likewise.
+	(testsuite/20_util/is_trivially_move_constructible/value.cc): Likewise.
+	(testsuite/20_util/make_signed/requirements/typedefs_neg.cc): Adjust.
+	(testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc):
+	Likewise.
+
 2017-05-16  Jonathan Wakely  <jwakely@redhat.com>
 
 	* testsuite/experimental/source_location/1.cc: Change expected result
diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index aac7cff..390b6f4 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -924,213 +924,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     : public __is_default_constructible_safe<_Tp>::type
     { };
 
-
-  // Implementation of is_constructible.
-
-  // The hardest part of this trait is the binary direct-initialization
-  // case, because we hit into a functional cast of the form T(arg).
-  // This implementation uses different strategies depending on the
-  // target type to reduce the test overhead as much as possible:
-  //
-  // a) For a reference target type, we use a static_cast expression
-  //    modulo its extra cases.
-  //
-  // b) For a non-reference target type we use a ::new expression.
-  struct __do_is_static_castable_impl
-  {
-    template<typename _From, typename _To, typename
-             = decltype(static_cast<_To>(declval<_From>()))>
-      static true_type __test(int);
-
-    template<typename, typename>
-      static false_type __test(...);
-  };
-
-  template<typename _From, typename _To>
-    struct __is_static_castable_impl
-    : public __do_is_static_castable_impl
-    {
-      typedef decltype(__test<_From, _To>(0)) type;
-    };
-
-  template<typename _From, typename _To>
-    struct __is_static_castable_safe
-    : public __is_static_castable_impl<_From, _To>::type
-    { };
-
-  // __is_static_castable
-  template<typename _From, typename _To>
-    struct __is_static_castable
-    : public integral_constant<bool, (__is_static_castable_safe<
-				      _From, _To>::value)>
-    { };
-
-  // Implementation for non-reference types. To meet the proper
-  // variable definition semantics, we also need to test for
-  // is_destructible in this case.
-  // This form should be simplified by a single expression:
-  // ::delete ::new _Tp(declval<_Arg>()), see c++/51222.
-  struct __do_is_direct_constructible_impl
-  {
-    template<typename _Tp, typename _Arg, typename
-	     = decltype(::new _Tp(declval<_Arg>()))>
-      static true_type __test(int);
-
-    template<typename, typename>
-      static false_type __test(...);
-  };
-
-  template<typename _Tp, typename _Arg>
-    struct __is_direct_constructible_impl
-    : public __do_is_direct_constructible_impl
-    {
-      typedef decltype(__test<_Tp, _Arg>(0)) type;
-    };
-
-  template<typename _Tp, typename _Arg>
-    struct __is_direct_constructible_new_safe
-    : public __and_<is_destructible<_Tp>,
-                    __is_direct_constructible_impl<_Tp, _Arg>>
-    { };
-
-  template<typename, typename>
-    struct is_same;
-
-  template<typename, typename>
-    struct is_base_of;
-
-  template<typename>
-    struct remove_reference;
-
-  template<typename _From, typename _To, bool
-           = __not_<__or_<is_void<_From>,
-                          is_function<_From>>>::value>
-    struct __is_base_to_derived_ref;
-
-  template<typename _Tp, typename... _Args>
-    struct is_constructible;
-
-  // Detect whether we have a downcast situation during
-  // reference binding.
-  template<typename _From, typename _To>
-    struct __is_base_to_derived_ref<_From, _To, true>
-    {
-      typedef typename remove_cv<typename remove_reference<_From
-        >::type>::type __src_t;
-      typedef typename remove_cv<typename remove_reference<_To
-        >::type>::type __dst_t;
-      typedef __and_<__not_<is_same<__src_t, __dst_t>>,
-		     is_base_of<__src_t, __dst_t>,
-		     __not_<is_constructible<__dst_t, _From>>> type;
-      static constexpr bool value = type::value;
-    };
-
-  template<typename _From, typename _To>
-    struct __is_base_to_derived_ref<_From, _To, false>
-    : public false_type
-    { };
-
-  template<typename _From, typename _To, bool
-           = __and_<is_lvalue_reference<_From>,
-                    is_rvalue_reference<_To>>::value>
-    struct __is_lvalue_to_rvalue_ref;
-
-  // Detect whether we have an lvalue of non-function type
-  // bound to a reference-compatible rvalue-reference.
-  template<typename _From, typename _To>
-    struct __is_lvalue_to_rvalue_ref<_From, _To, true>
-    {
-      typedef typename remove_cv<typename remove_reference<
-        _From>::type>::type __src_t;
-      typedef typename remove_cv<typename remove_reference<
-        _To>::type>::type __dst_t;
-      typedef __and_<__not_<is_function<__src_t>>,
-        __or_<is_same<__src_t, __dst_t>,
-		    is_base_of<__dst_t, __src_t>>> type;
-      static constexpr bool value = type::value;
-    };
-
-  template<typename _From, typename _To>
-    struct __is_lvalue_to_rvalue_ref<_From, _To, false>
-    : public false_type
-    { };
-
-  // Here we handle direct-initialization to a reference type as
-  // equivalent to a static_cast modulo overshooting conversions.
-  // These are restricted to the following conversions:
-  //    a) A base class value to a derived class reference
-  //    b) An lvalue to an rvalue-reference of reference-compatible
-  //       types that are not functions
-  template<typename _Tp, typename _Arg>
-    struct __is_direct_constructible_ref_cast
-    : public __and_<__is_static_castable<_Arg, _Tp>,
-                    __not_<__or_<__is_base_to_derived_ref<_Arg, _Tp>,
-                                 __is_lvalue_to_rvalue_ref<_Arg, _Tp>
-                   >>>
-    { };
-
-  template<typename _Tp, typename _Arg>
-    struct __is_direct_constructible_new
-    : public conditional<is_reference<_Tp>::value,
-			 __is_direct_constructible_ref_cast<_Tp, _Arg>,
-			 __is_direct_constructible_new_safe<_Tp, _Arg>
-			 >::type
-    { };
-
-  template<typename _Tp, typename _Arg>
-    struct __is_direct_constructible
-    : public __is_direct_constructible_new<_Tp, _Arg>::type
-    { };
-
-  // Since default-construction and binary direct-initialization have
-  // been handled separately, the implementation of the remaining
-  // n-ary construction cases is rather straightforward. We can use
-  // here a functional cast, because array types are excluded anyway
-  // and this form is never interpreted as a C cast.
-  struct __do_is_nary_constructible_impl
-  {
-    template<typename _Tp, typename... _Args, typename
-             = decltype(_Tp(declval<_Args>()...))>
-      static true_type __test(int);
-
-    template<typename, typename...>
-      static false_type __test(...);
-  };
-
-  template<typename _Tp, typename... _Args>
-    struct __is_nary_constructible_impl
-    : public __do_is_nary_constructible_impl
-    {
-      typedef decltype(__test<_Tp, _Args...>(0)) type;
-    };
-
-  template<typename _Tp, typename... _Args>
-    struct __is_nary_constructible
-    : public __is_nary_constructible_impl<_Tp, _Args...>::type
-    {
-      static_assert(sizeof...(_Args) > 1,
-                    "Only useful for > 1 arguments");
-    };
-
-  template<typename _Tp, typename... _Args>
-    struct __is_constructible_impl
-    : public __is_nary_constructible<_Tp, _Args...>
-    { };
-
-  template<typename _Tp, typename _Arg>
-    struct __is_constructible_impl<_Tp, _Arg>
-    : public __is_direct_constructible<_Tp, _Arg>
-    { };
-
-  template<typename _Tp>
-    struct __is_constructible_impl<_Tp>
-    : public is_default_constructible<_Tp>
-    { };
-
   /// is_constructible
   template<typename _Tp, typename... _Args>
     struct is_constructible
-    : public __is_constructible_impl<_Tp, _Args...>::type
+      : public __bool_constant<__is_constructible(_Tp, _Args...)>
     { };
 
   template<typename _Tp, bool = __is_referenceable<_Tp>::value>
@@ -1255,26 +1052,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     : public __is_nothrow_move_constructible_impl<_Tp>
     { };
 
-  template<typename _Tp, typename _Up>
-    class __is_assignable_helper
-    {
-      template<typename _Tp1, typename _Up1,
-	       typename = decltype(declval<_Tp1>() = declval<_Up1>())>
-	static true_type
-	__test(int);
-
-      template<typename, typename>
-	static false_type
-	__test(...);
-
-    public:
-      typedef decltype(__test<_Tp, _Up>(0)) type;
-    };
-
   /// is_assignable
   template<typename _Tp, typename _Up>
     struct is_assignable
-      : public __is_assignable_helper<_Tp, _Up>::type
+      : public __bool_constant<__is_assignable(_Tp, _Up)>
     { };
 
   template<typename _Tp, bool = __is_referenceable<_Tp>::value>
@@ -1364,8 +1145,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   /// is_trivially_constructible
   template<typename _Tp, typename... _Args>
     struct is_trivially_constructible
-    : public __and_<is_constructible<_Tp, _Args...>, integral_constant<bool,
-			__is_trivially_constructible(_Tp, _Args...)>>
+    : public __bool_constant<__is_trivially_constructible(_Tp, _Args...)>
     { };
 
   /// is_trivially_default_constructible
@@ -1405,45 +1185,95 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   { };
 
   /// is_trivially_copy_constructible
+
+  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
+    struct __is_trivially_copy_constructible_impl;
+
   template<typename _Tp>
-    struct is_trivially_copy_constructible
+    struct __is_trivially_copy_constructible_impl<_Tp, false>
+    : public false_type { };
+
+  template<typename _Tp>
+    struct __is_trivially_copy_constructible_impl<_Tp, true>
     : public __and_<is_copy_constructible<_Tp>,
 		    integral_constant<bool,
 			__is_trivially_constructible(_Tp, const _Tp&)>>
     { };
 
+  template<typename _Tp>
+    struct is_trivially_copy_constructible
+    : public __is_trivially_copy_constructible_impl<_Tp>
+    { };
+
   /// is_trivially_move_constructible
+
+  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
+    struct __is_trivially_move_constructible_impl;
+
   template<typename _Tp>
-    struct is_trivially_move_constructible
+    struct __is_trivially_move_constructible_impl<_Tp, false>
+    : public false_type { };
+
+  template<typename _Tp>
+    struct __is_trivially_move_constructible_impl<_Tp, true>
     : public __and_<is_move_constructible<_Tp>,
 		    integral_constant<bool,
 			__is_trivially_constructible(_Tp, _Tp&&)>>
     { };
 
+  template<typename _Tp>
+    struct is_trivially_move_constructible
+    : public __is_trivially_move_constructible_impl<_Tp>
+    { };
+
   /// is_trivially_assignable
   template<typename _Tp, typename _Up>
     struct is_trivially_assignable
-    : public __and_<is_assignable<_Tp, _Up>,
-		    integral_constant<bool,
-			__is_trivially_assignable(_Tp, _Up)>>
+    : public __bool_constant<__is_trivially_assignable(_Tp, _Up)>
     { };
 
   /// is_trivially_copy_assignable
+
+  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
+    struct __is_trivially_copy_assignable_impl;
+
   template<typename _Tp>
-    struct is_trivially_copy_assignable
+    struct __is_trivially_copy_assignable_impl<_Tp, false>
+    : public false_type { };
+
+  template<typename _Tp>
+    struct __is_trivially_copy_assignable_impl<_Tp, true>
     : public __and_<is_copy_assignable<_Tp>,
 		    integral_constant<bool,
 			__is_trivially_assignable(_Tp&, const _Tp&)>>
     { };
 
+  template<typename _Tp>
+    struct is_trivially_copy_assignable
+    : public __is_trivially_copy_assignable_impl<_Tp>
+    { };
+
   /// is_trivially_move_assignable
+
+  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
+    struct __is_trivially_move_assignable_impl;
+
   template<typename _Tp>
-    struct is_trivially_move_assignable
+    struct __is_trivially_move_assignable_impl<_Tp, false>
+    : public false_type { };
+
+  template<typename _Tp>
+    struct __is_trivially_move_assignable_impl<_Tp, true>
     : public __and_<is_move_assignable<_Tp>,
 		    integral_constant<bool,
 			__is_trivially_assignable(_Tp&, _Tp&&)>>
     { };
 
+  template<typename _Tp>
+    struct is_trivially_move_assignable
+    : public __is_trivially_move_assignable_impl<_Tp>
+    { };
+
   /// is_trivially_destructible
   template<typename _Tp>
     struct is_trivially_destructible
diff --git a/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc b/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc
index dc9daeb..4e254e8 100644
--- a/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc
+++ b/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc
@@ -18,7 +18,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-error "static assertion failed" "" { target *-*-* } 2259 }
+// { dg-error "static assertion failed" "" { target *-*-* } 2089 }
 
 #include <utility>
 
diff --git a/libstdc++-v3/testsuite/20_util/is_trivially_copy_assignable/value.cc b/libstdc++-v3/testsuite/20_util/is_trivially_copy_assignable/value.cc
index b002246..902aa5e 100644
--- a/libstdc++-v3/testsuite/20_util/is_trivially_copy_assignable/value.cc
+++ b/libstdc++-v3/testsuite/20_util/is_trivially_copy_assignable/value.cc
@@ -88,4 +88,6 @@ void test01()
 		MoveOnly>(false), "");
   static_assert(test_property<is_trivially_copy_assignable, 
 		MoveOnly2>(false), "");
+  static_assert(test_property<is_trivially_copy_assignable,
+		void>(false), "");
 }
diff --git a/libstdc++-v3/testsuite/20_util/is_trivially_copy_constructible/value.cc b/libstdc++-v3/testsuite/20_util/is_trivially_copy_constructible/value.cc
index 845e058..627410b 100644
--- a/libstdc++-v3/testsuite/20_util/is_trivially_copy_constructible/value.cc
+++ b/libstdc++-v3/testsuite/20_util/is_trivially_copy_constructible/value.cc
@@ -82,4 +82,6 @@ void test01()
 		MoveOnly>(false), "");
   static_assert(test_property<is_trivially_copy_constructible, 
 		MoveOnly2>(false), "");
+  static_assert(test_property<is_trivially_copy_constructible,
+		void>(false), "");
 }
diff --git a/libstdc++-v3/testsuite/20_util/is_trivially_move_assignable/value.cc b/libstdc++-v3/testsuite/20_util/is_trivially_move_assignable/value.cc
index 68833b6..2210483 100644
--- a/libstdc++-v3/testsuite/20_util/is_trivially_move_assignable/value.cc
+++ b/libstdc++-v3/testsuite/20_util/is_trivially_move_assignable/value.cc
@@ -88,4 +88,6 @@ void test01()
 		MoveOnly>(true), "");
   static_assert(test_property<is_trivially_move_assignable, 
 		MoveOnly2>(false), "");
+  static_assert(test_property<is_trivially_move_assignable, 
+		void>(false), "");
 }
diff --git a/libstdc++-v3/testsuite/20_util/is_trivially_move_constructible/value.cc b/libstdc++-v3/testsuite/20_util/is_trivially_move_constructible/value.cc
index ad6045b..9a21b6e 100644
--- a/libstdc++-v3/testsuite/20_util/is_trivially_move_constructible/value.cc
+++ b/libstdc++-v3/testsuite/20_util/is_trivially_move_constructible/value.cc
@@ -82,4 +82,6 @@ void test01()
 		MoveOnly>(true), "");
   static_assert(test_property<is_trivially_move_constructible, 
 		MoveOnly2>(false), "");
+  static_assert(test_property<is_trivially_move_constructible,
+		void>(false), "");
 }
diff --git a/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc b/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc
index 664fb70..e3e80f9 100644
--- a/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc
+++ b/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc
@@ -47,4 +47,4 @@ void test01()
 // { dg-error "required from here" "" { target *-*-* } 39 }
 // { dg-error "required from here" "" { target *-*-* } 41 }
 
-// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1924 }
+// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1754 }
diff --git a/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc b/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc
index 6d64717..86b0c2d 100644
--- a/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc
+++ b/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc
@@ -47,5 +47,5 @@ void test01()
 // { dg-error "required from here" "" { target *-*-* } 39 }
 // { dg-error "required from here" "" { target *-*-* } 41 }
 
-// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1820 }
-// { dg-error "declaration of" "" { target *-*-* } 1777 }
+// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1650 }
+