https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56785
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- The cause is that every N-tuple hierarchy ends with an empty _Tuple_impl<N> base, so when there are several of those in the same hierarchy they need to have separate addresses. It should be possible to fix by eliminating that terminal objet in the inheritance hierarchy. The obvious way duplicates a chunk of code, I think it should be possible to do it in a nicer way, which I'm experimenting with.
