In which situations is the C++ copy constructor called?

Question

I know of the following situations in c++ where the copy constructor would be invoked:

1. when an existing object is assigned an object of it own class

Answer 1

The following are the cases when copy constructor is called.

1. When instantiating one object and initializing it with values from another object.
2. When passing an object by value.
3. When an object is returned from a function by value.