[Bug c++/71737] New: ICE following 2x pack expansion in non-pack with template alias

[pkeir at outlook dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71737

            Bug ID: 71737
           Summary: ICE following 2x pack expansion in non-pack with
                    template alias
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pkeir at outlook dot com
  Target Milestone: ---

The code below (and attached) produces an ICE with gcc (GCC) 7.0.0 20160608
(experimental) when compiled using g++ with "-c -std=c++11".

template <template <typename ...> class TT>
struct quote {
  template <typename ...Ts>
  using apply = TT<Ts...>;
};

template <typename>
using to_int_t = int;

using t = quote<quote<to_int_t>::apply>::apply<int>;