When compiling with Clang 5.0.1 one gets two warnings about nested type
specifiers that were probably not intended to be there in the first
place. The first one is asking a *_t type trait for ::type and the
second one is asking for Entity::Entity.

The exact warnings given by Clang were:

/duneci/modules/dune-subgrid/dune/subgrid/common/variant.hh:31:66: warning: ISO C++ specifies that qualified reference to 'type' is a constructor name rather than a type in this context, despite preceding 'typename' keyword [-Winjected-class-name]
    using Storage = typename std::aligned_storage_t<sizeof(Tp)>::type;
                                                                 ^

/duneci/modules/dune-subgrid/dune/subgrid/subgrid.hh:1190:67: warning: ISO C++ specifies that qualified reference to 'Entity' is a constructor name rather than a type in this context, despite preceding 'typename' keyword [-Winjected-class-name]
            typedef typename HostGrid::template Codim<0>::Entity::Entity HostGridElement;
                                                                  ^