CUDA 12.1, 12.2, 12.3, 12.4 constexpr issues, FIXED in CUDA 12.5

[havogt]

CUDA 12.1 and CUDA 12.2 seem to have (once again) problems with constexpr construction.

E.g. the following was fine in 12.0, but fails to compile now:

template <class T>
struct foo {
    T m;
    constexpr foo(T const &a) : m(a) {}
};
int main() {
    auto f = foo([]{});
}

where foo can be std::tuple.

[havogt]

12.3 affected as well #1768

[havogt]

12.4 fixed the above example, but this small variation still fails

template <class T>
struct foo {
    T m;
    constexpr foo(T const &a) : m(a) {}
};

template <class T>
struct bar {
    T m;
    constexpr bar(T const &a) : m(a) {}
};

int main() {
    auto f = foo(bar([] {}));
}

[havogt]

The issues are fixed in CUDA 12.5.

Leaving this open for reference.