[INFORMATION]
A definition for a pure virtual function is not needed unless explicitly called with the qualified-id syntax (nested-name-specifier [template] unqualified-id).
class A{
public:
virtual void f(void) = 0; // pure virtual function.
};
class B : public A{
public:
void f(void){ int local=0; }
};
void main(void){
B b;
b.A::f(); // generate a linking error cause
// no object is defined.
b.f(); // call the function defined in
// B class.
}
Correct the source.