#include <iostream>

class Base{
  private:
   int a;
  public:
   Base():a(5){ 
  }

  virtual void print(){
   std::cout<<"In base "<<this->a<<std::endl;
  }
}

int main(){
 Base* b = new Base;
 b->print();
 return 0;
}

Line 15: error: new types may not be defined in a return type
compilation terminated due to -Wfatal-errors.