Why not specifying the copy constructor is usually bad

The compiler has only limited knowledge of what you really want to do.

All it can do is to make a member-wise copy of all the data members in your class.

If you have a pointer, it will copy the pointer -- but then your new object has a pointer pointing to somewhere outside the object’s scope.

// the copy constructor

cube::cube (const cube& c)

{

length = c.length;

*color = *c.color;

}

Instead of this

// the copy constructor

cube::cube (const cube& c)

{

length = c.length;

color = c.color;

}

you will get this

and it can lead to a lot of problems.

Once more: Always provide a copy constructor.

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