Different uses of noexcept

In the book The C++ Programming Language it is written that you can declare a function to be conditionally noexcept. For example:

template<typename T>
void my_fct(T& x) noexcept(std::is_pod<T>::value);

noexcept takes a predicate that must be a constant expression (in the example std::is_pod<T>::value).

However, in the book it is also written:

The noexcept() operator takes an expression as its argument and returns true if the compiler knows that it cannot throw and false otherwise.

Taking this into account, consider:

constexpr bool f() { return true; }

void g() noexcept(f())
{
    f();
}

Is g() marked as noexcept or not? I see two possibilities:

1. The call f() is evaluated at compile-time because it is marked constexpr, it returns true and as a result g() is marked noexcept.
2. The compiler cannot determine that f() cannot throw an exception because f() is not marked noexcept. As a result g() is not marked noexcept.

Which one does happen? How can I select one or other behavior for noexcept?