C2022: Pure virtual can be called only using explicit scope resolution

[ERROR]

Pure virtual functions can be called from a constructor of an abstract class; the effect of calling a pure virtual function directly or indirectly for the object being created from such a constructor is an error.

  class A{

  

  public:

  

    virtual void f(void) = 0;

  

    A(){

  

      f();

  

    }

  

  };

  

A pure virtual can be defined. It can be called using explicit qualification only.

  class A{

  

  public:

  

    virtual void f(void) = 0;

  

    A(){

  

      A::f();

  

    }

  

  };

  

  void A::f(void){ // defined somewhere

  

    //...

  

  }