allocating memory

[vbx_wx]

Is there any diference between:

X* x = new X;
	X* y = operator new X;

[arkoenig]

Yes -- the first one is well-formed C++ (if X is a type and x isn't already defined in the same scope) and the second isn't.

[StuXYZ]

As arkoenig said, as you have written it, it doesn't compile.

If you are using the construct operator new, you need to do it like this:

class X
{
  X() { std::cout<<"Constructor called "<<std::endl; }
  ~X() { std::cout<<"Destructor called "<<std::endl; }
};

int main() 
{
  X *x=new X;
  X *y= static_cast<X*>(operator new (sizeof(X)));
  delete x;
  delete y;
}

BUT be very careful: the constructor is only called ONCE. ie only for x, not for y. Be very very careful calling it, because if you don't have a POD [plain old data] type class, you are opening yourself to a nightmare of runtime problems.

[arkoenig]

Putting it differently: If you have to ask about how to use operator new, you shouldn't be using it.