The copy constructor is used in the previous situations. If a copy constructor is not used in the first two cases, it will lead to an object pointer pointing to deleted memory. For the third case, the ...

Make the copy constructor private. Of course, this might also have the side-effect of preventing the use of the STL container, given that being copy constructible is, y'know, a requirement. Use a ...

From a purely object-oriented perspective, 'copy semantics' is the right way to preserve control over object ownership. But in those scenarios where ownership becomes irrelevant, C++11 'move semantics ...