[Bug c++/116769] Instantiation of defaulted default constructor with non default constructible NDSMIs

[dangelog at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116769

--- Comment #4 from Giuseppe D'Angelo <dangelog at gmail dot com> ---
Hi, thanks for investigating.

That divergence is a bit worrying, I can't quite understand what's going on.

Also, all compilers seem to accept this variation, which one would naively
assume "equivalent" to the previous testcase:


struct NDC { NDC(int); };

template <typename T>
struct Wrap
{
    Wrap() : t() {}
    Wrap(const T &t) : t(t) {}

    T t;
};

static_assert(std::is_default_constructible_v<Wrap<NDC>>);