Which has non-virtual destructor?
A C++ class containing virtual member functions has a non-virtual destructor. Since this class has virtual member functions, it will be used as a base class. The use of non-virtual destructors in base classes is dangerous because it can cause objects to be torn down incorrectly.
What is a non-virtual destructor?
A non-virtual destructor signifies that a class should not be used as a base-class. Not really; a non-virtual destructor signifies that deleting an instance of derived via a base pointer will not work.
What happens if base class destructor is not virtual?
Deleting a derived class object using a pointer of base class type that has a non-virtual destructor results in undefined behavior. To correct this situation, the base class should be defined with a virtual destructor.
Do derived classes need a virtual destructor?
All base classes with a virtual function should define a virtual destructor. If an application attempts to delete a derived class object through a base class pointer, the result is undefined if the base class destructor is non-virtual.
Can C++ have virtual destructors?
Can a destructor be pure virtual in C++? Yes, it is possible to have a pure virtual destructor. Pure virtual destructors are legal in standard C++ and one of the most important things to remember is that if a class contains a pure virtual destructor, it must provide a function body for the pure virtual destructor.
Can destructors be private in CPP?
Private Destructor in C++ Destructors with the access modifier as private are known as Private Destructors. Whenever we want to prevent the destruction of an object, we can make the destructor private.
Can a destructor be virtual in C++?
Is virtual constructor possible in C++?
In C++, the constructor cannot be virtual, because when a 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.
Can destructor be virtual?
Yes, it is possible to have a pure virtual destructor. Pure virtual destructors are legal in standard C++ and one of the most important things to remember is that if a class contains a pure virtual destructor, it must provide a function body for the pure virtual destructor.
Is the default destructor virtual?
The implicitly-declared destructor is virtual (because the base class has a virtual destructor) and the lookup for the deallocation function (operator delete()) results in a call to ambiguous, deleted, or inaccessible function.
Can we have virtual destructor?
Does a derived class need a destructor?
No. You never need to explicitly call a destructor (except with placement new). A derived class’s destructor (whether or not you explicitly define one) automagically invokes the destructors for base class subobjects. Base classes are destructed after member objects.
A non-virtual destructor signifies that a class should not be used as a base-class. Not really; a non-virtual destructor signifies that deleting an instance of derived via a base pointer will not work. For example: class Base {}; class Derived : public Base {}; Base* b = new Derived; delete b; // Does not call Derived’s destructor!
Can I use derived from a class without a virtual destructor?
And there are certainly cases where it makes sense to derive from a class which doesn’t have a virtual destructor. The reason why the base class destructor should be virtual is so that you can delete through a pointer to the base class. If the derivation is private, you don’t have to worry about this, since your Derived* won’t convert to a Base* .
How to turn off Virtuality in a derived class?
You’re question isn’t really clear. If the base class has a virtual destructor, the derived class will have one, regardless. There’s no way to turn virtuality off, once it’s been declared. And there are certainly cases where it makes sense to derive from a class which doesn’t have a virtual destructor.
Is it possible to have empty virtual base destructor in compilator?
In this case compilator knows what you want and no warnings generate. The decision with empty virtual base destructor is not too well but acceptable. You needn’t set attribute final. But this isn’t the thing you want.You also needn’t define empty virtual base method Foo too Best is: