The relation between Forward declaration and destructors
c++, forward-declaration
Solution
Indeed, your forward declaration introduces an incomplete type that is later defined with a non-trivial destructor, and that can't be used in a delete expression:
From n3337, paragraph 5.3.5/5:
5 If the object being deleted has incomplete class type at the point of deletion and the complete class has a non-trivial destructor or a deallocation function, the behavior is undefined.
Problem
I have the following code: ``` #include <iostream> using namespace std; class CForward; void func(CForward* frw) { delete frw; } class CForward { public: ~CForward() { cout << "Forward" << endl; } }; int main() { func(new CForward); cin.get(); } ``` I ran the program, and it printed nothing. Why? in main, I created `new CFoward`, and in `func` I deleted it and called it destructor. It seems that the destructor have not been called. Why? Is that related anyhow to the forward decleration?