The idea of compiler-generated functions is that, if some functions of a class are so trivial to write that their code would nearly be boilerplate, the compiler will take care of writing them for you.

This feature has been here since C++98, where the compiler would try to generate:
- a default constructor X(), that calls the default constructor of each class member and base class,
- a copy constructor X(X const& other), that calls a copy constructor on each member and base class,
- a copy assignment operator X& operator=(X const& other), that calls a copy assignment operator on each class member and base class,
- the destructor ~X(), that calls the destructor of each class member and base class. Note that this default-generated destructor is never virtual (unless it is for a class inheriting from one that has a virtual destructor).

With C++11, the compiler generates 2 new functions related to move semantics:
- a move constructor X(X&& other), that calls a move constructor of each class member and base class,
- a move assignment operator X& operator=(X&& other), that calls a move assignment operator on each class member and base class.
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