diff --git a/include/boost/mp11/detail/mp_with_index.hpp b/include/boost/mp11/detail/mp_with_index.hpp
index 2d2a66f..1062877 100644
--- a/include/boost/mp11/detail/mp_with_index.hpp
+++ b/include/boost/mp11/detail/mp_with_index.hpp
@@ -80,9 +80,9 @@ template<> struct mp_with_index_impl_<2>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -93,10 +93,10 @@ template<> struct mp_with_index_impl_<3>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -107,11 +107,11 @@ template<> struct mp_with_index_impl_<4>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
         case 3: return std::forward<F>(f)( mp_size_t<K+3>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -122,12 +122,12 @@ template<> struct mp_with_index_impl_<5>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
         case 3: return std::forward<F>(f)( mp_size_t<K+3>() );
         case 4: return std::forward<F>(f)( mp_size_t<K+4>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -138,13 +138,13 @@ template<> struct mp_with_index_impl_<6>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
         case 3: return std::forward<F>(f)( mp_size_t<K+3>() );
         case 4: return std::forward<F>(f)( mp_size_t<K+4>() );
         case 5: return std::forward<F>(f)( mp_size_t<K+5>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -155,6 +155,7 @@ template<> struct mp_with_index_impl_<7>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -162,7 +163,6 @@ template<> struct mp_with_index_impl_<7>
         case 4: return std::forward<F>(f)( mp_size_t<K+4>() );
         case 5: return std::forward<F>(f)( mp_size_t<K+5>() );
         case 6: return std::forward<F>(f)( mp_size_t<K+6>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -173,6 +173,7 @@ template<> struct mp_with_index_impl_<8>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -181,7 +182,6 @@ template<> struct mp_with_index_impl_<8>
         case 5: return std::forward<F>(f)( mp_size_t<K+5>() );
         case 6: return std::forward<F>(f)( mp_size_t<K+6>() );
         case 7: return std::forward<F>(f)( mp_size_t<K+7>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -192,6 +192,7 @@ template<> struct mp_with_index_impl_<9>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -201,7 +202,6 @@ template<> struct mp_with_index_impl_<9>
         case 6: return std::forward<F>(f)( mp_size_t<K+6>() );
         case 7: return std::forward<F>(f)( mp_size_t<K+7>() );
         case 8: return std::forward<F>(f)( mp_size_t<K+8>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -212,6 +212,7 @@ template<> struct mp_with_index_impl_<10>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -222,7 +223,6 @@ template<> struct mp_with_index_impl_<10>
         case 7: return std::forward<F>(f)( mp_size_t<K+7>() );
         case 8: return std::forward<F>(f)( mp_size_t<K+8>() );
         case 9: return std::forward<F>(f)( mp_size_t<K+9>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -233,6 +233,7 @@ template<> struct mp_with_index_impl_<11>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -244,7 +245,6 @@ template<> struct mp_with_index_impl_<11>
         case 8: return std::forward<F>(f)( mp_size_t<K+8>() );
         case 9: return std::forward<F>(f)( mp_size_t<K+9>() );
         case 10: return std::forward<F>(f)( mp_size_t<K+10>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -255,6 +255,7 @@ template<> struct mp_with_index_impl_<12>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -267,7 +268,6 @@ template<> struct mp_with_index_impl_<12>
         case 9: return std::forward<F>(f)( mp_size_t<K+9>() );
         case 10: return std::forward<F>(f)( mp_size_t<K+10>() );
         case 11: return std::forward<F>(f)( mp_size_t<K+11>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -278,6 +278,7 @@ template<> struct mp_with_index_impl_<13>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -291,7 +292,6 @@ template<> struct mp_with_index_impl_<13>
         case 10: return std::forward<F>(f)( mp_size_t<K+10>() );
         case 11: return std::forward<F>(f)( mp_size_t<K+11>() );
         case 12: return std::forward<F>(f)( mp_size_t<K+12>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -302,6 +302,7 @@ template<> struct mp_with_index_impl_<14>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -316,7 +317,6 @@ template<> struct mp_with_index_impl_<14>
         case 11: return std::forward<F>(f)( mp_size_t<K+11>() );
         case 12: return std::forward<F>(f)( mp_size_t<K+12>() );
         case 13: return std::forward<F>(f)( mp_size_t<K+13>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -327,6 +327,7 @@ template<> struct mp_with_index_impl_<15>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -342,7 +343,6 @@ template<> struct mp_with_index_impl_<15>
         case 12: return std::forward<F>(f)( mp_size_t<K+12>() );
         case 13: return std::forward<F>(f)( mp_size_t<K+13>() );
         case 14: return std::forward<F>(f)( mp_size_t<K+14>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };
@@ -353,6 +353,7 @@ template<> struct mp_with_index_impl_<16>
     {
         switch( i )
         {
+        default: BOOST_MP11_UNREACHABLE();
         case 0: return std::forward<F>(f)( mp_size_t<K+0>() );
         case 1: return std::forward<F>(f)( mp_size_t<K+1>() );
         case 2: return std::forward<F>(f)( mp_size_t<K+2>() );
@@ -369,7 +370,6 @@ template<> struct mp_with_index_impl_<16>
         case 13: return std::forward<F>(f)( mp_size_t<K+13>() );
         case 14: return std::forward<F>(f)( mp_size_t<K+14>() );
         case 15: return std::forward<F>(f)( mp_size_t<K+15>() );
-        default: BOOST_MP11_UNREACHABLE();
         }
     }
 };