Static assertions and SFINAE

Consider this:

template <typename T>
struct hash
{
     static_assert(false,"Not implemented.");
};

struct unhashable {};

template <typename T>
auto test(const T &t) -> decltype((*(hash<T> const *)nullptr)(t),int);

void test(...);

int main()
{
    std::cout << std::is_same<decltype(test(std::declval<unhashable>())),void>::value;
}

Apart from obviously missing headers, should this compile?

In other words, I am asking if the static assertion failure triggering inside a trailing decltype while deducing the return value of an overloaded function template is requested to halt the compilation, or if the overload has simply to be discarded.

On gcc 4.7, compilation fails. I am pretty positive though that this will compile ok in gcc 4.8 (but cannot check at this very moment). Who is right?