nullptr vtable vs2017

test.cpp

#include <functional>
struct Base {
  virtual void f() const = 0;
};
int main() {
  struct : public Base {
    void f() const override {}
  } a, b; // vTables of 'a' and 'b' contain nulls

  // not crucial for problem, helps to emphasize problem
  std::invoke(&Base::f, a); 
  return 0;
}