name hiding and fragile base problem

I've seen it stated that C++ has name hiding for the purposes of reducing the fragile base class problem. However, I definitely don't see how this helps. If the base class introduces a function or overload that previously did not exist, it might conflict with those introduced by the derived class, or unqualified calls to global functions or member functions- but what I don't see is how this is different for overloads. Why should overloads of virtual functions be treated differently to, well, any other function?

Edit: Let me show you a little more what I'm talking about.

struct base {
    virtual void foo();
    virtual void foo(int);
    virtual void bar();
    virtual ~base();
};
struct derived : base {
    virtual void foo();
};

int main() {
    derived d;
    d.foo(1); // Error- foo(int) is hidden
    d.bar(); // Fine- calls base::bar()
}

Here, foo(int) is treated differently to bar(), because it's an overload.