Differing return type for virtual functions

Question

A virtual function\'s return type should be the same type that is in base class, or covariant. But why do we have this restriction?

Answer 1

Because how would the code that's using the return value cope with all sorts of unrelated types coming back? e.g.:

class A
{
public:
    virtual float func();
};

class B: public A
{
public:
    virtual char *func();
};

A *p = (some_condition) ? new A() : new B();
p->func();  // Oh no! What is the type?