[Python-Dev] GC and ExtensionClass

[skip@pobox.com (Skip Montanaro)]

    Martin> That *should* work, except that it also has its 'methods' field
    Martin> where tp_traverse would go, and its class_flags field where
    Martin> tp_clear would go.

Okay, so I'm completed confused now.  I extended the definition of
ECTypeType to include this after the doc string slot:

      (traverseproc)0,              /* tp_traverse */
      (inquiry)0,                   /* tp_clear */
      (richcmpfunc)0,               /* rich comparisons */
      0L,                           /* weak reference enabler */

    #ifdef COUNT_ALLOCS
      /* these must be last */
      0,                            /* tp_alloc */
      0,                            /* tp_free */
      0,                            /* tp_maxalloc */
      (struct _typeobject *)0,      /* tp_next */
    #endif

When I looked at the definition of ECType, after the doc string I saw

      METHOD_CHAIN(ExtensionClass_methods)

as Martin indicated.  I can't simply insert the same zeroes at the end of
the ECType def'n as I did at the end of the ECTypeType definition.  Where
does this METHOD_CHAIN thing go?  I looked at the def'n of struct
_typeobject in Include/object.h but didn't see a slot that looked suitable.

FWIW, when I build Python and PyGtk with Py_DEBUG defined as Neil suggested,
I get 

    Fatal Python error: UNREF invalid object

when I run my failing script.  This is with and without making any changes
to ECType or ECTypeType.

Skip