[Bug c++/67593] New: Partial specialization: "Template argument involves template parameters"

[columbo@gmx-topmail.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67593

            Bug ID: 67593
           Summary: Partial specialization: "Template argument involves
                    template parameters"
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: columbo@gmx-topmail.de
  Target Milestone: ---

template <typename T>
struct outer
{
        template <T...> struct inner {};
        template <T... Ts> struct inner<T{}, Ts...> {};
};

This fails to compile, although the code is well-formed (in particular,
[temp.class.spec]/(8.1) and (8.2) are not violated); Apparently, GCC fails to
correctly distinguish nested levels of template parameters.