[Patches] Object leak in recursive comparison checker

[Mark Hammond]

Im fairly confident there is a dictionary leak in the new
get_inprogress_dict() function in object.c

It is clear that this function returns a dictionary with _no_ reference
count added.  However, when it creates the dict, it returns an INCREF'd
dict.  Fortunately, we also stash the reference to this object in another
dict, so we can safely DECREF our created reference (well, at least as
safely as the other branch can return the existing dict with no new
reference)

The diff below is a 12 line context diff to help you see all relevant code.
If you look at the usage of this function, you can also see the result is
never DECREFd.

My object reference leak vanished, and the full test suite completes, after
making this change...

Mark.

diff -c -1 -2 -r2.70 object.c
*** object.c	2000/05/03 23:44:35	2.70
--- object.c	2000/06/09 04:16:02
***************
*** 342,365 ****
--- 342,367 ----
  	}
  	inprogress = PyDict_GetItem(tstate_dict, _PyCompareState_Key);
  	if (inprogress == NULL) {
  		PyErr_Clear();
  		inprogress = PyDict_New();
  		if (inprogress == NULL)
  			return NULL;
  		if (PyDict_SetItem(tstate_dict, _PyCompareState_Key,
  				   inprogress) == -1) {
  		    Py_DECREF(inprogress);
  		    return NULL;
  		}
+ 		/* The tstate_dict has a ref - we can now free ours */
+ 		Py_DECREF(inprogress);
  	}
  	return inprogress;
  }

  static PyObject *
  make_pair(v, w)
  	PyObject *v, *w;
  {
  	PyObject *pair;

  	pair = PyTuple_New(2);
  	if (pair == NULL) {




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Mark.