Why C++ does not have a virtual constructor?

The virtual mechanism works only when we have a base class pointer to a derived class object.

In C++, constructor cannot be virtual, because when constructor of a class is executed there is no virtual table in the memory, means no virtual pointer defined yet. So, the constructor should always be non-virtual.

But virtual destructor is possible. Here is an example


using namespace std;
class b {
   { cout<<"Constructing base \n"; }
   virtual ~b()
   { cout<<"Destructing base \n"; }
class d: public b {
      { cout<<"Constructing derived \n"; }
      { cout<<"Destructing derived \n"; }
int main(void) {
   d *derived = new d();
   b *bptr = derived;
   delete bptr;
   return 0;


Constructing base
Constructing derived
Destructing derived
Destructing base