diff --git a/include/boost/type_traits/detail/size_t_trait_def.hpp b/include/boost/type_traits/detail/size_t_trait_def.hpp
index ac7e2f8..8cea9b4 100644
--- a/include/boost/type_traits/detail/size_t_trait_def.hpp
+++ b/include/boost/type_traits/detail/size_t_trait_def.hpp
@@ -18,14 +18,14 @@
 
 #include <cstddef>
 
-#define BOOST_TT_AUX_SIZE_T_BASE(C) public ::boost::integral_constant<std::size_t,C>
 // Obsolete. Remove.
+#define BOOST_TT_AUX_SIZE_T_BASE(C) public ::boost::integral_constant<std::size_t,C>
 #define BOOST_TT_AUX_SIZE_T_TRAIT_VALUE_DECL(C) /**/
 
 
 #define BOOST_TT_AUX_SIZE_T_TRAIT_DEF1(trait,T,C) \
 template< typename T > struct trait \
-    : BOOST_TT_AUX_SIZE_T_BASE(C) \
+    : public ::boost::integral_constant<std::size_t,C> \
 { \
 public:\
     BOOST_MPL_AUX_LAMBDA_SUPPORT(1,trait,(T)) \
@@ -36,7 +36,7 @@ BOOST_TT_AUX_TEMPLATE_ARITY_SPEC(1,trait) \
 
 #define BOOST_TT_AUX_SIZE_T_TRAIT_SPEC1(trait,spec,C) \
 template<> struct trait<spec> \
-    : BOOST_TT_AUX_SIZE_T_BASE(C) \
+    : public ::boost::integral_constant<std::size_t,C> \
 { \
 public:\
     BOOST_MPL_AUX_LAMBDA_SUPPORT_SPEC(1,trait,(spec)) \
@@ -45,7 +45,7 @@ public:\
 
 #define BOOST_TT_AUX_SIZE_T_TRAIT_PARTIAL_SPEC1_1(param,trait,spec,C) \
 template< param > struct trait<spec> \
-    : BOOST_TT_AUX_SIZE_T_BASE(C) \
+    : public ::boost::integral_constant<std::size_t,C> \
 { \
 }; \
 /**/