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From: "jlame646 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/107945] static constexpr incomplete (depedent) data member
 of a class template and in-member initialized incorrectly accepted
Date: Tue, 02 Apr 2024 14:26:50 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107945

--- Comment #4 from Jason Liam <jlame646 at gmail dot com> ---
Here is another invalid snippet that gcc accepts but both clang and msvc
rejects correctly. https://godbolt.org/z/sz4rczEaG

```
#include <array>

template<class T, std::size_t N>
    requires std::is_arithmetic_v<T> && (N >=3D 1)
class Vector
{
    static constexpr std::size_t Dimension =3D N;
    std::array<T, Dimension> Elements;

public:
    constexpr Vector() noexcept : Elements{} {}
    constexpr ~Vector() =3D default;
    static constexpr Vector ZeroVector{};
};

int main()
{
    Vector<float, 7> boo =3D Vector<float, 7>::ZeroVector;
}
```

Related thread
https://stackoverflow.com/questions/78248691/static-data-member-of-template=
-class-type-constexpr-vs-const-constinit=