diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
index 8cf0f2d0974..bd517d08843 100644
--- a/gcc/cp/constraint.cc
+++ b/gcc/cp/constraint.cc
@@ -3754,6 +3754,9 @@ diagnose_trait_expr (tree expr, tree args)
     case CPTK_IS_AGGREGATE:
       inform (loc, "  %qT is not an aggregate", t1);
       break;
+    case CPTK_IS_ARITHMETIC:
+      inform (loc, "  %qT is not an arithmetic type", t1);
+      break;
     case CPTK_IS_TRIVIALLY_COPYABLE:
       inform (loc, "  %qT is not trivially copyable", t1);
       break;
diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
index 8b7fece0cc8..a95aeeaf778 100644
--- a/gcc/cp/cp-trait.def
+++ b/gcc/cp/cp-trait.def
@@ -82,6 +82,7 @@ DEFTRAIT_EXPR (IS_TRIVIALLY_ASSIGNABLE, "__is_trivially_assignable", 2)
 DEFTRAIT_EXPR (IS_TRIVIALLY_CONSTRUCTIBLE, "__is_trivially_constructible", -1)
 DEFTRAIT_EXPR (IS_TRIVIALLY_COPYABLE, "__is_trivially_copyable", 1)
 DEFTRAIT_EXPR (IS_UNION, "__is_union", 1)
+DEFTRAIT_EXPR (IS_ARITHMETIC, "__is_arithmetic", 1)
 DEFTRAIT_EXPR (REF_CONSTRUCTS_FROM_TEMPORARY, "__reference_constructs_from_temporary", 2)
 DEFTRAIT_EXPR (REF_CONVERTS_FROM_TEMPORARY, "__reference_converts_from_temporary", 2)
 /* FIXME Added space to avoid direct usage in GCC 13.  */
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 8fb47fd179e..4531f047d73 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -12118,6 +12118,9 @@ trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_UNION:
       return type_code1 == UNION_TYPE;
 
+    case CPTK_IS_ARITHMETIC:
+      return ARITHMETIC_TYPE_P (type1);
+
     case CPTK_IS_ASSIGNABLE:
       return is_xible (MODIFY_EXPR, type1, type2);
 
@@ -12296,6 +12299,7 @@ finish_trait_expr (location_t loc, cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_ENUM:
     case CPTK_IS_UNION:
     case CPTK_IS_SAME:
+    case CPTK_IS_ARITHMETIC:
       break;
 
     case CPTK_IS_LAYOUT_COMPATIBLE:
diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
index f343e153e56..3d63b0101d1 100644
--- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
+++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
@@ -146,3 +146,6 @@
 #if !__has_builtin (__remove_cvref)
 # error "__has_builtin (__remove_cvref) failed"
 #endif
+#if !__has_builtin (__is_arithmetic)
+# error "__has_builtin (__is_arithmetic) failed"
+#endif
diff --git a/gcc/testsuite/g++.dg/ext/is_arithmetic.C b/gcc/testsuite/g++.dg/ext/is_arithmetic.C
new file mode 100644
index 00000000000..fd35831f646
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/is_arithmetic.C
@@ -0,0 +1,33 @@
+// { dg-do compile { target c++11 } }
+
+#include <testsuite_tr1.h>
+
+using namespace __gnu_test;
+
+#define SA(X) static_assert((X),#X)
+#define SA_TEST_CATEGORY(TRAIT, TYPE, EXPECT)	\
+  SA(TRAIT(TYPE) == EXPECT);					\
+  SA(TRAIT(const TYPE) == EXPECT);				\
+  SA(TRAIT(volatile TYPE) == EXPECT);			\
+  SA(TRAIT(const volatile TYPE) == EXPECT)
+
+SA_TEST_CATEGORY(__is_arithmetic, void, false);
+
+SA_TEST_CATEGORY(__is_arithmetic, char, true);
+SA_TEST_CATEGORY(__is_arithmetic, signed char, true);
+SA_TEST_CATEGORY(__is_arithmetic, unsigned char, true);
+SA_TEST_CATEGORY(__is_arithmetic, wchar_t, true);
+SA_TEST_CATEGORY(__is_arithmetic, short, true);
+SA_TEST_CATEGORY(__is_arithmetic, unsigned short, true);
+SA_TEST_CATEGORY(__is_arithmetic, int, true);
+SA_TEST_CATEGORY(__is_arithmetic, unsigned int, true);
+SA_TEST_CATEGORY(__is_arithmetic, long, true);
+SA_TEST_CATEGORY(__is_arithmetic, unsigned long, true);
+SA_TEST_CATEGORY(__is_arithmetic, long long, true);
+SA_TEST_CATEGORY(__is_arithmetic, unsigned long long, true);
+SA_TEST_CATEGORY(__is_arithmetic, float, true);
+SA_TEST_CATEGORY(__is_arithmetic, double, true);
+SA_TEST_CATEGORY(__is_arithmetic, long double, true);
+
+// Sanity check.
+SA_TEST_CATEGORY(__is_arithmetic, ClassType, false);
diff --git a/gcc/testsuite/g++.dg/tm/pr46567.C b/gcc/testsuite/g++.dg/tm/pr46567.C
index 6d791484448..b16f7b685e7 100644
--- a/gcc/testsuite/g++.dg/tm/pr46567.C
+++ b/gcc/testsuite/g++.dg/tm/pr46567.C
@@ -217,16 +217,16 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
       typedef __true_type __type;
     };
   template<typename _Tp>
-    struct __is_arithmetic
+    struct ____is_arithmetic
     : public __traitor<__is_integer<_Tp>, __is_floating<_Tp> >
     { };
   template<typename _Tp>
     struct __is_fundamental
-    : public __traitor<__is_void<_Tp>, __is_arithmetic<_Tp> >
+    : public __traitor<__is_void<_Tp>, ____is_arithmetic<_Tp> >
     { };
   template<typename _Tp>
     struct __is_scalar
-    : public __traitor<__is_arithmetic<_Tp>, __is_pointer<_Tp> >
+    : public __traitor<____is_arithmetic<_Tp>, __is_pointer<_Tp> >
     { };
   template<typename _Tp>
     struct __is_char
diff --git a/gcc/testsuite/g++.dg/torture/pr57107.C b/gcc/testsuite/g++.dg/torture/pr57107.C
index 4dbd32bd298..4329a6eb4e1 100644
--- a/gcc/testsuite/g++.dg/torture/pr57107.C
+++ b/gcc/testsuite/g++.dg/torture/pr57107.C
@@ -25,9 +25,9 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
 	enum {
 	    __value = 0 };
     };
-    template<typename _Tp>     struct __is_arithmetic     : public __traitor<__is_integer<_Tp>, __is_floating<_Tp> >     {
+    template<typename _Tp>     struct ____is_arithmetic     : public __traitor<__is_integer<_Tp>, __is_floating<_Tp> >     {
     };
-    template<typename _Tp>     struct __is_scalar     : public __traitor<__is_arithmetic<_Tp>, __is_pointer<_Tp> >     {
+    template<typename _Tp>     struct __is_scalar     : public __traitor<____is_arithmetic<_Tp>, __is_pointer<_Tp> >     {
     };
 }
 namespace __gnu_cxx __attribute__ ((__visibility__ ("default"))) {
diff --git a/libstdc++-v3/include/bits/cpp_type_traits.h b/libstdc++-v3/include/bits/cpp_type_traits.h
index 4312f32a4e0..95c55433c81 100644
--- a/libstdc++-v3/include/bits/cpp_type_traits.h
+++ b/libstdc++-v3/include/bits/cpp_type_traits.h
@@ -381,7 +381,7 @@ __INT_N(__GLIBCXX_TYPE_INT_N_3)
   // An arithmetic type is an integer type or a floating point type
   //
   template<typename _Tp>
-    struct __is_arithmetic
+    struct ____is_arithmetic
     : public __traitor<__is_integer<_Tp>, __is_floating<_Tp> >
     { };
 
@@ -390,7 +390,7 @@ __INT_N(__GLIBCXX_TYPE_INT_N_3)
   // 
   template<typename _Tp>
     struct __is_scalar
-    : public __traitor<__is_arithmetic<_Tp>, __is_pointer<_Tp> >
+    : public __traitor<____is_arithmetic<_Tp>, __is_pointer<_Tp> >
     { };
 
   //
diff --git a/libstdc++-v3/include/c_global/cmath b/libstdc++-v3/include/c_global/cmath
index b0ba395eb5c..9f11e652418 100644
--- a/libstdc++-v3/include/c_global/cmath
+++ b/libstdc++-v3/include/c_global/cmath
@@ -1255,8 +1255,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #ifndef __CORRECT_ISO_CPP11_MATH_H_PROTO_INT
   template<typename _Tp, typename _Up>
     constexpr typename
-    __gnu_cxx::__enable_if<(__is_arithmetic<_Tp>::__value
-			    && __is_arithmetic<_Up>::__value), bool>::__type
+    __gnu_cxx::__enable_if<(____is_arithmetic<_Tp>::__value
+			    && ____is_arithmetic<_Up>::__value), bool>::__type
     isgreater(_Tp __x, _Up __y)
     {
       typedef typename __gnu_cxx::__promote_2<_Tp, _Up>::__type __type;
@@ -1281,8 +1281,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #ifndef __CORRECT_ISO_CPP11_MATH_H_PROTO_INT
   template<typename _Tp, typename _Up>
     constexpr typename
-    __gnu_cxx::__enable_if<(__is_arithmetic<_Tp>::__value
-			    && __is_arithmetic<_Up>::__value), bool>::__type
+    __gnu_cxx::__enable_if<(____is_arithmetic<_Tp>::__value
+			    && ____is_arithmetic<_Up>::__value), bool>::__type
     isgreaterequal(_Tp __x, _Up __y)
     {
       typedef typename __gnu_cxx::__promote_2<_Tp, _Up>::__type __type;
@@ -1307,8 +1307,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #ifndef __CORRECT_ISO_CPP11_MATH_H_PROTO_INT
   template<typename _Tp, typename _Up>
     constexpr typename
-    __gnu_cxx::__enable_if<(__is_arithmetic<_Tp>::__value
-			    && __is_arithmetic<_Up>::__value), bool>::__type
+    __gnu_cxx::__enable_if<(____is_arithmetic<_Tp>::__value
+			    && ____is_arithmetic<_Up>::__value), bool>::__type
     isless(_Tp __x, _Up __y)
     {
       typedef typename __gnu_cxx::__promote_2<_Tp, _Up>::__type __type;
@@ -1333,8 +1333,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #ifndef __CORRECT_ISO_CPP11_MATH_H_PROTO_INT
   template<typename _Tp, typename _Up>
     constexpr typename
-    __gnu_cxx::__enable_if<(__is_arithmetic<_Tp>::__value
-			    && __is_arithmetic<_Up>::__value), bool>::__type
+    __gnu_cxx::__enable_if<(____is_arithmetic<_Tp>::__value
+			    && ____is_arithmetic<_Up>::__value), bool>::__type
     islessequal(_Tp __x, _Up __y)
     {
       typedef typename __gnu_cxx::__promote_2<_Tp, _Up>::__type __type;
@@ -1359,8 +1359,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #ifndef __CORRECT_ISO_CPP11_MATH_H_PROTO_INT
   template<typename _Tp, typename _Up>
     constexpr typename
-    __gnu_cxx::__enable_if<(__is_arithmetic<_Tp>::__value
-			    && __is_arithmetic<_Up>::__value), bool>::__type
+    __gnu_cxx::__enable_if<(____is_arithmetic<_Tp>::__value
+			    && ____is_arithmetic<_Up>::__value), bool>::__type
     islessgreater(_Tp __x, _Up __y)
     {
       typedef typename __gnu_cxx::__promote_2<_Tp, _Up>::__type __type;
@@ -1385,8 +1385,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #ifndef __CORRECT_ISO_CPP11_MATH_H_PROTO_INT
   template<typename _Tp, typename _Up>
     constexpr typename
-    __gnu_cxx::__enable_if<(__is_arithmetic<_Tp>::__value
-			    && __is_arithmetic<_Up>::__value), bool>::__type
+    __gnu_cxx::__enable_if<(____is_arithmetic<_Tp>::__value
+			    && ____is_arithmetic<_Up>::__value), bool>::__type
     isunordered(_Tp __x, _Up __y)
     {
       typedef typename __gnu_cxx::__promote_2<_Tp, _Up>::__type __type;
@@ -1397,7 +1397,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #else
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     fpclassify(_Tp __f)
     {
@@ -1407,7 +1407,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isfinite(_Tp __f)
     {
@@ -1416,7 +1416,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isinf(_Tp __f)
     {
@@ -1425,7 +1425,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isnan(_Tp __f)
     {
@@ -1434,7 +1434,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isnormal(_Tp __f)
     {
@@ -1443,7 +1443,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     signbit(_Tp __f)
     {
@@ -1452,7 +1452,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isgreater(_Tp __f1, _Tp __f2)
     {
@@ -1461,7 +1461,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isgreaterequal(_Tp __f1, _Tp __f2)
     {
@@ -1470,7 +1470,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isless(_Tp __f1, _Tp __f2)
     {
@@ -1479,7 +1479,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     islessequal(_Tp __f1, _Tp __f2)
     {
@@ -1488,7 +1488,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     islessgreater(_Tp __f1, _Tp __f2)
     {
@@ -1497,7 +1497,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isunordered(_Tp __f1, _Tp __f2)
     {
diff --git a/libstdc++-v3/include/c_std/cmath b/libstdc++-v3/include/c_std/cmath
index 588ee1e6dc4..fe351182f53 100644
--- a/libstdc++-v3/include/c_std/cmath
+++ b/libstdc++-v3/include/c_std/cmath
@@ -467,7 +467,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #undef isunordered
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     fpclassify(_Tp __f)
     {
@@ -477,7 +477,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isfinite(_Tp __f)
     {
@@ -486,7 +486,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isinf(_Tp __f)
     {
@@ -495,7 +495,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isnan(_Tp __f)
     {
@@ -504,7 +504,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isnormal(_Tp __f)
     {
@@ -513,7 +513,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     signbit(_Tp __f)
     {
@@ -522,7 +522,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isgreater(_Tp __f1, _Tp __f2)
     {
@@ -531,7 +531,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isgreaterequal(_Tp __f1, _Tp __f2)
     {
@@ -540,7 +540,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isless(_Tp __f1, _Tp __f2)
     {
@@ -549,7 +549,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value, 
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     islessequal(_Tp __f1, _Tp __f2)
     {
@@ -558,7 +558,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     islessgreater(_Tp __f1, _Tp __f2)
     {
@@ -567,7 +567,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isunordered(_Tp __f1, _Tp __f2)
     {
diff --git a/libstdc++-v3/include/tr1/cmath b/libstdc++-v3/include/tr1/cmath
index ba1b60cc945..07a66d06a01 100644
--- a/libstdc++-v3/include/tr1/cmath
+++ b/libstdc++-v3/include/tr1/cmath
@@ -307,7 +307,7 @@ namespace tr1
 
   /// Function template definitions [8.16.3].
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     fpclassify(_Tp __f)
     {
@@ -317,7 +317,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isfinite(_Tp __f)
     {
@@ -326,7 +326,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isinf(_Tp __f)
     {
@@ -335,7 +335,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isnan(_Tp __f)
     {
@@ -344,7 +344,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isnormal(_Tp __f)
     {
@@ -353,7 +353,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     signbit(_Tp __f)
     {
@@ -362,7 +362,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isgreater(_Tp __f1, _Tp __f2)
     {
@@ -371,7 +371,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isgreaterequal(_Tp __f1, _Tp __f2)
     {
@@ -380,7 +380,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isless(_Tp __f1, _Tp __f2)
     {
@@ -389,7 +389,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     islessequal(_Tp __f1, _Tp __f2)
     {
@@ -398,7 +398,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     islessgreater(_Tp __f1, _Tp __f2)
     {
@@ -407,7 +407,7 @@ namespace tr1
     }
 
   template<typename _Tp>
-    inline typename __gnu_cxx::__enable_if<__is_arithmetic<_Tp>::__value,
+    inline typename __gnu_cxx::__enable_if<____is_arithmetic<_Tp>::__value,
 					   int>::__type
     isunordered(_Tp __f1, _Tp __f2)
     {
