[Bug c++/58435] New: Applying a type transformation to a list: const ignored

[iavr at image dot ntua.gr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58435

            Bug ID: 58435
           Summary: Applying a type transformation to a list: const
                    ignored
           Product: gcc
           Version: 4.8.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: iavr at image dot ntua.gr

The following applies a type transformation F to a list L of types T..., in
particular for a transformation that adds "const":

------------------------------------------------------------------------

   template <template <typename...> class F, typename P> struct apply;

   template <
       template <typename...> class F,
       template <typename...> class L, typename... T
   > struct apply <F, L <T...> > { typedef L <F <T>...> type; };

   template <typename T> using map = const T;
   template <typename> struct A { };
   template <typename> void dummy();

   int main() { dummy <apply <map, A <int> >::type>(); }

------------------------------------------------------------------------

It fails to link because of

   undefined reference to `void dummy<A<int> >()'

instead of the expected

  undefined reference to `void dummy<A<const int> >()'

i.e., "const" is ignored. It works for any other transformation I have tried.