Re: delete [] of Derived objects through Base object which has virtual dtor

From:
xavier <xavier>
Newsgroups:
comp.lang.c++
Date:
Tue, 13 May 2008 00:04:19 +0200
Message-ID:
<4828bee3$0$875$ba4acef3@news.orange.fr>
Barry wrote:

subramanian100in@yahoo.com, India wrote:

* Kai-Uwe Bux <jkherci...@gmx.net> wrote:

subramanian10...@yahoo.com wrote:


Well formed -- maybe. But the code has undefined behavior as per
[5.3.5/3]:

  ... In the second alternative (delete array) if the dynamic type of
the
  object to be deleted differs from its static type, the behavior is
  undefined.


I do not know about static and dynamic type.
Please give me an example so that I can understand them.


class Base
{
public:
  virtual ~Base() {}
};

class Derived : public Base
{};

int main()
{
  Base* p = new Derived(); // static type of p is "pointer to Base"
                           // dynamic type of p is "pointer to Derived"
}


Hello,

in the above example, what will happen if we add 'delete p;' at the end
of main(). What will be deleted ? Only the base class part or both base
and derived part of instantied object ?

thanks

Xavier

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