[Bug c++/63809] Missing warning on extra template

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63809

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Reduced testcase:
template<typename T1, typename T2, int a>
struct binary_traits{};

template <>
template <typename T1, typename T2>
struct binary_traits <T1, T2, 1>
{
    typedef int result_type;
};

----- CUT ----
This is rejected since GCC 8 with:
<source>:6:8: error: too many template-parameter-lists
 struct binary_traits <T1, T2, 1>
        ^~~~~~~~~~~~~~~~~~~~~~~~~

I suspect there is a dup now.