[Insight-developers] destructor/smart pointer clean up causin g crashes?

[Miller, James V (CRD)]

I fixed the problem I was having, I had code in this test like

  itk::XMLFileOutputWindow::Pointer logger = itk::XMLFileOutputWindow::New();
  logger->SetInstance(logger);
  logger->Delete();

I was calling logger->Delete() to reduce the number of references to the 
output window since the output window class keeps a static handle to the
output window.

When the code is like the above, my program crashes on exit.  It looks
as though the logger is getting deleted twice on output.  Once for 
when the logger variable goes out of scope and once when the static
handle to logger gets deleted.  This is one too many times.

When I remove the logger->Delete() line, the program exits without error
and Purify reports no leaks.

Calling Delete() on my smartpointer, just propagated the Delete() call
to the underlying object.  The smartpointer itself did not release zero
out its pointer. So when the smart pointer went out of scope, it tried 
to delete its reference again.

Can we keep people from calling Delete() on a smart pointer (perhaps by making it 
protected)?



-----Original Message-----
From: Miller, James V (CRD) 
Sent: Wednesday, October 03, 2001 2:05 PM
To: 'Bill Hoffman'; Wilson M Chang;
insight-developers@public.kitware.com
Subject: RE: [Insight-developers] destructor/smart pointer clean up
causin g crashes?


We are having some other problems with crashes on exit.

The Testing/Code/BasicFilters/itkStreamingImageFilterTest2 is 
crashing on exit.  This particular test using a subclass of the
FileOutputWindow.  Walking through the debugger, an exception
is thrown when the smart pointer to the "static instance" of the 
output window is destroyed.


-----Original Message-----
From: Bill Hoffman [mailto:bill.hoffman@kitware.com]
Sent: Wednesday, October 03, 2001 1:02 PM
To: Wilson M Chang; insight-developers@public.kitware.com
Subject: Re: [Insight-developers] destructor/smart pointer clean up
causing crashes?


I would have to see the code to tell. 


-Bill


At 12:30 PM 10/3/2001 -0400, Wilson M Chang wrote:
>I was writing a file reader following very closely the PNG file reader
>code that is currently in place.  I noticed that it was causing the
>program to crash when the program was exiting (on the last bracket of 
>main() ) while calling of destructors for ImageIO and such, as well as
>cleaning up the smart pointers. Miraculously, this crashing went away as
>soon as the image reader (and corresponding factory) was added to the
>ITKIO library.  Has anybody had similar problems or have any idea why this
>was happening when the code was external to ITK?  
>
>wilson  
>
>_______________________________________________
>Insight-developers mailing list
>Insight-developers@public.kitware.com
>http://public.kitware.com/mailman/listinfo/insight-developers 

_______________________________________________
Insight-developers mailing list
Insight-developers@public.kitware.com
http://public.kitware.com/mailman/listinfo/insight-developers
_______________________________________________
Insight-developers mailing list
Insight-developers@public.kitware.com
http://public.kitware.com/mailman/listinfo/insight-developers