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Destructor usually deletes any extra resources allocated by the object.

Note:

• Destructor can NOT be allowed to leave! A leave from a destructor may cause the program to terminate abruptly. In S60 3rd edition and later releases a leave is an exception and there can be only one active exception at a time. The destructor may have been called as a part of a routine to handle an exception (leave) and raising another exception will cause the program to be terminated.
  

• Always delete objects your class owns, from the class destructor.
• Don’t delete objects that you don’t own (those that you merely use).
• Don’t allocate twice (this will cause a memory leak).
• Don’t delete twice (this will corrupt the heap).
• When you delete outside of the destructor, immediately set the pointer to zero.
• When you are reallocating, you must use the sequence ‘delete, set pointer to zero, allocate’, just in case the allocation fails.

See also delete.