Calling a virtual base class's overloaded constructor

Question

Is there a (practical) way to by-pass the normal (virtual) constructor calling order?

Example:

class A
{
    const int i;

public:
          


        

Answer 1

Such are the rules. There are rules for overriding virtual functions and rules for constructing virtual base subobjects. Although both are very similar conceptually, they follow completely different rules, for a reason: overriding a virtual function is explicit. Calling a constructor is implicit for the default constructor.

Virtual functions in virtual base classes are only required to have one final overrider, an overrider that overrides all others overriders. (Virtual functions in non-virtual base classes cannot possibly have two overriders such that one does not override the other.)

But virtual base class constructors are always called from the most derived class, and usually in the implicit form of not bothering to mention the virtual base class in the ctor-init-list, as most classes designed to be used as virtual base classes are "pure interfaces" with no data members and no user initialization.