Trying to delete object with non-zero reference count.

Engineering
1

When my program exits, the title appears. Does it represent my memory leak？

2

Probably. It is hard to tell without more information.

3

do you have any method about checkthe itk memory lack ?

4

I remember that VTK can bring up a dialog with a message similar to “Trying to delete object with non-zero reference count”. But I don’t think ITK does that. @blowekamp @mihail.isakov Do you agree?

5

ITK has the warning here

LightObject::~LightObject()
{
  /**
   * warn user if reference counting is on and the object is being referenced
   * by another object.
   */
  if (m_ReferenceCount > 0)
  {
    // A general exception safety rule is that destructors should
    // never throw.  Something is wrong with a program that reaches
    // this point anyway.  Also this is the least-derived class so the
    // whole object has been destroyed by this point anyway.  Just
    // issue a warning, do not call `itkExceptionMacro`.
    itkWarningMacro("Trying to delete object with non-zero reference count.");
  }
}

I have the warning at one point, seems to be harmless, Valgrind doesn’t detect leak at this point, so far nothing happens. Probably it is my mistake somewhere, not sure. I shall look again little later.

Edit:
Also see this post. There is a minimal example.

1 Like
6

Probably it is my mistake somewhere, not sure. I shall look again little later.

I have found my mistake. I used itk::MapContainer on a stack.

#include <itkMapContainer.h>
int main(int, char**)
{
	itk::MapContainer<int, int> map;
	return 0;
}

r@deb2:~/tmp/test5/build$ ./test 
WARNING: In /home/r/itk/ITK/Modules/Core/Common/src/itkLightObject.cxx, line 182
LightObject (0x7ffc902d3020): Trying to delete object with non-zero reference count.

It should be:

#include <itkMapContainer.h>
int main(int, char**)
{
	itk::MapContainer<int, int>::Pointer map = itk::MapContainer<int, int>::New();
	return 0;
}

r@deb2:~/tmp/test5/build$ ./test 
r@deb2:~/tmp/test5/build$
2 Likes
7

thank you,I resolved an error that is the same as yours, but I still have a warning, and when I debug a breakpoint, the system already prints that warning the first time I enter the destructor.

8

@Niels_Dekker Is this a bug? I thought we had a mechanism to prevent these object from being constructed on the stack?

9

There is a mechanism via a macro which is usually applied to filters. Maybe it was forgotten for MapContainer?

1 Like
10

Apparently the MapContainer() default-constructor was originally declared protected:

It was then afterwards declared public instead, on November 30, 2001, commit ENH:Unified documentation style. · InsightSoftwareConsortium/ITK@e9c0020 · GitHub
Here:
ITK/itkMapContainer.h at e9c002026368eee503bc39d363b9c9344d587385 · InsightSoftwareConsortium/ITK · GitHub

HTH, Niels

11

Since it has a New macro and Pointer type, it should probably use constructor disallow macro. Anyone willing to submit a PR?