'auto_ptr' has destructive copy semantics which may be non-intuitive and can lead to erroneous usage.

   
   void foo( auto_ptr<int> ai );
   
   void bar()
   {
      auto_ptr<int> ai( new int );
      foo( ai );   // destructive copy
      *ai = 10;    // error ai no longer exists
   }

If you use 'auto_ptr' take note of the following:

- Do not use auto_ptr with array types.

- Only use auto_ptr with dynamically allocated variables.

- Be aware that implicit conversions can take place between auto_ptrs of different types where a conversion exists for the underlying pointer types.

- Use auto_ptr where "ownership-transfer semantics" are required, for example do not use auto_ptr where you need two pointers to the same object concurrently.