How much different is this from slicing in C++?

IE:

  #include <iostream>
  using namespace std;

  struct Greeter {
    void greet() {
        cout << "Hello, World!" << endl;
    }
  };

  struct BaseGreeter: Greeter {};

  struct LazyGreeter: BaseGreeter {
    void greet() {
        cout << "sup" << endl;
    }
  };

  int main() {
    Greeter greeter = LazyGreeter();
    greeter.greet(); // Prints "Hello, World"

    return 0;
  }