MSVC fails to compile
#include <iostream>
template<int N, int = N>
struct A;
template<int, int V>
struct A{static constexpr int VALUE = V;};
int main() {
A<1> a;
std::cout << a.VALUE;
}
with (3): error C2065: 'N': unknown identifier
(10): error C2975: 'V': invalid template argument 'A', constant expression expected (roughly translated).
clang compiles it silently.
So, the question: rotten code or demented MSVC?
MSVC version = VS 2019.