Does destroying and recreating an object make all pointers to this object invalid?

Question

This is a follow-up to this question. Suppose I have this code:

class Class {
    public virtual method()
    {
        this->~Class();
        new( this          


        

Answer 1

The object pointer doesn't become invalid at any time (assuming your destructor doesn't call delete this). Your object was never deallocated, it has only called it's destructor, i.e. it has cleaned up its internal state (with regard to implementation, please note that standard strictly defines that the object is destroyed after destructor call). As you have used placement new to instantiate the new object at the exactly same address, it is technically ok.

This exact scenario is covered by section 3.8.7 of C++ standard:

If, after the lifetime of an object has ended and before the storage which the object occupied is reused or released, a new object is created at the storage location which the original object occupied, a pointer that pointed to the original object, a reference that referred to the original object, or the name of the original object will automatically refer to the new object and, once the lifetime of the new object has started, can be used to manipulate the new object [...]

That said, this is interesting only as learning code, as production code, this is horrible :)