Steven wrote on Saturday, March 19, 2011 at 18:40:26:
Actually, I got it from n3242 which is a recent C++0x draft.
are you sure that this draft is going to become the final version of std? if so further discussion is pointless since the std kills the very opportunity to implement such a feature (and some custom allocation strategies as well)
Okay. Let's do this a different way (a little later in the section):
"In the first alternative (delete object), if the static type of the operand is different from its dynamic type, the static type shall be a base class of the operand’s dynamic type and the static type shall have a virtual destructor or the behavior is undefined."
i believe this part concerns slicing as when one deletes an object of some derived class D using pointer to the base class B this way ~D() destructor has no chance to be executed and we have the whole bunch of unwanted effects furthermore when '::delete operator()' function is called the compiler may miscalculate the size of the object to be deleted since sizeof(D) may differ from sizeof(B) and the deallocation function likely be supplied with wrong size argument which again may cause unexpected effects in my variant of implementation all destructors involved are trivial (read: they are never called) and the global deallocation function ('::operator delete()') is never called on the operand of the delete expression so i believe it shouldn't cause undefined behavior anyway -- Pavel P.S. if you notice a grammar mistake or weird phrasing in my message please point it out