Question

Are there any issues, like compile time operator, with sizeof associated with new?

Answer 1

new is an operator so you can overload it for some (or all) of your classes.

EDIT: I’ll try to clarify to address @sbi’s comments below.

Consider two classes:

class Base
{
}

class Derived : public Base
{
}

Let’s assume that new() is a function, and we want to specialize it for the Base class and its descendants. We would have the “basic” new() function:

void *new(size_t size);

Overloaded functions cannot differ by their return types alone, so we can’t do:

Base *new(size_t size);  // Illegal.

We can’t use member functions because they need an existing instance to be called. We could use static member functions:

class Base
{
    static Base *new();
}

But the resulting syntax when allocating a instance of Derived would be quite awkward:

Derived *derived = Base::new();  // Uh?