[Bug c++/61401] Wrong treatment of empty template-argument packs during deduction

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61401

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |INVALID

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The template Y can only be instantiated with an empty parameter pack, which
makes it invalid.  [temp.res] p8 says:

"If every valid specialization of a variadic template requires an empty
template parameter pack, the template is ill-formed, no diagnostic required"