How operator new calls the constructor of class?

Question

I know that, new operator will call the constructor of class.

But how it\'s happening, what is ground level techniques used for this.

Answer 1

It's not really the new operator that calls the constructor. It is more the compiler that translate the following line:

MyClass * mine = new MyClass();

Into the following:

MyClass * mine = malloc(sizeof(MyClass));  // Allocates memory
mine->MyClass();                           // Calls constructor

With other error handling code that other answers have noted.