Any way to prevent dynamic allocation of a class?

Question

I\'m using a C++ base class and subclasses (let\'s call them A and B for the sake of clarity) in my embedded system.

It\'s time- and space-critical, so I really nee

Answer 1

Just make operator new private

Answer 2

You can poison operator new in just the same way as you can a copy constructor. Just be sure not to poison placement new. A virtual destructor would still be a fine recommendation.

int main() {
    char data[sizeof(Derived)];
    if (condition)
        new (data) Derived();
    else
        new (data) Base();
    Base* ptr = reinterpret_cast<Base*>(&data[0]);
    ptr->~Base();
}

Answer 3

class A
{
private:
    void *operator new(size_t);
    ...
};

The elipses are for the other overrides of operator new and the rest of the class.