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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/91798] Compiler rejects code due to template specialization
 of auto parameter value.
Date: Sat, 06 Apr 2024 02:45:24 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D91798

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |SUSPENDED

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1647

And maybe others.

Note my other testcase was a full specialization rather than a partial.
Here is one with a partial which removes the variadic :
```
//Get type parameter at given index.
template<auto i, class T>
struct param
{
    static_assert(i > 0, "Index into parameter pack cannot be negative!");
    using type =3D typename param<i - 1, T>::type;
};

template<class T>
struct param<0, T>
{
    using type =3D T;
};

int main()
{
    typename param<0u, int>::type x =3D 'a';
    static_cast<void>(x);
}
```

Both GCC and EDG agree on this while clang and MSVC disagree. This is
definitely DR 1647 then.=20

So suspended as the defect report is still active.=