Deleting a Base pointer that is pointing to a Derived object

Question

Will this work, or will there be slicing (i.e. only the memory corresponding to that occupied by a Base object will be freed, rather than for the whole Derived object):

Base* ptr = new Derived;
delete ptr;

If not, will this?

delete static_cast<Derived*>(ptr);

If the destructor of `Base` is `virtual`, everything will be okay. The compiler will most likely warn you if this is not the case. — arne, Jan 16 '14 at 13:29
http://stackoverflow.com/questions/461203/when-to-use-virtual-destructors — Daniel E., Jan 16 '14 at 13:37

Axel Borja · Accepted Answer · 2014-01-16T14:27:57.763

3

This will work.

Calling methods of a derived object by a base object pointer, is one of polymorphism fundamentals.

However, be sure that the base class destructor is virtual, to properly destruct your object.

edited Jan 16 '14 at 14:27

answered Jan 16 '14 at 13:31

Axel Borja

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Yes, it is. I'm just a bit tired, I think :) Thanks. – d7samurai Jan 16 '14 at 13:36

score 0 · Answer 2 · answered Jan 16 '14 at 13:58

this is not a object slicing . Object slicing happens when you cast a derived object to base object .Here you are manipulating a pointer . you can always make base class destructor virtual will make sure that the objects are deleted in the opposite order of creation

Deleting a Base pointer that is pointing to a Derived object

2 Answers2