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Re: warning: class 'xxx' has virtual functions but non-virtual destructor

I'm getting this warning:
class 'xxx' has virtual functions but non-virtual destructor

This warning is correct, but what does it really mean?  What are the
gotchas to having a class with virtual functions and a non-virtual
destructor?


Many people have given examples and reasons, but in essence a virtual destructor, like all other virtual things, allows the "right code" to run based on the runtime type of an object. It can be particularly important when destroying objects because, for example, a subclass might allocate gobs of memory that its superclass doesn't, and if you ran only the superclass destructor the extra memory would definitely be leaked.

[Of course, there are all kinds of places where you should use "virtual", which is what makes the "final" keyword in Java so brilliant by comparison, but I digress. :) ]

Kevin G.
http://homepage.mac.com/kmg/
mail to kevin at ieee dot org
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References: 
 >Re: warning: class 'xxx' has virtual functions but non-virtual destructor (From: Clark Cox <email@hidden>)



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