$12.8/2 - 'A non-template constructor for class X is a copy constructor if its first parameter is of type X&, const X&, volatile X& or const volatile X&, and either there are no other parameters or else all other parameters have default arguments (8.3.6).106)'
So far, I have not come across any example of a situation where there is a need to declare a copy constructor with additional default parameters.
Would like to know any real time use of such a copy constructor which take more than one parameter.