C API
-----
+- PyType_Ready(): If a type declares that it participates in gc
+ (Py_TPFLAGS_HAVE_GC), and its base class does not, and its base class's
+ tp_free slot is the default _PyObject_Del, and type does not define
+ a tp_free slot itself, _PyObject_GC_Del is assigned to type->tp_free.
+ Previously _PyObject_Del was inherited, which could at best lead to a
+ segfault. In addition, if even after this magic the type's tp_free
+ slot is _PyObject_Del or NULL, and the type is a base type
+ (Py_TPFLAGS_BASETYPE), TypeError is raised: since the type is a base
+ type, its dealloc function must call type->tp_free, and since the type
+ is gc'able, tp_free must not be NULL or _PyObject_Del.
+
New platforms
-------------
Py_XDECREF(self->inst_pers_func);
Py_XDECREF(self->dispatch_table);
PyMem_Free(self->write_buf);
- PyObject_GC_Del(self);
+ self->ob_type->tp_free((PyObject *)self);
}
static int
free(self->buf);
}
- PyObject_GC_Del(self);
+ self->ob_type->tp_free((PyObject *)self);
}
static int
#define INIT_STR(S) if (!( S ## _str=PyString_InternFromString(#S))) return -1;
+ if (PyType_Ready(&Unpicklertype) < 0)
+ return -1;
+ if (PyType_Ready(&Picklertype) < 0)
+ return -1;
+
INIT_STR(__class__);
INIT_STR(__getinitargs__);
INIT_STR(__dict__);
COPYSLOT(tp_dictoffset);
COPYSLOT(tp_init);
COPYSLOT(tp_alloc);
- COPYSLOT(tp_free);
COPYSLOT(tp_is_gc);
+ if ((type->tp_flags & Py_TPFLAGS_HAVE_GC) ==
+ (base->tp_flags & Py_TPFLAGS_HAVE_GC)) {
+ /* They agree about gc. */
+ COPYSLOT(tp_free);
+ }
+ else if ((type->tp_flags & Py_TPFLAGS_HAVE_GC) &&
+ type->tp_free == NULL &&
+ base->tp_free == _PyObject_Del) {
+ /* A bit of magic to plug in the correct default
+ * tp_free function when a derived class adds gc,
+ * didn't define tp_free, and the base uses the
+ * default non-gc tp_free.
+ */
+ type->tp_free = PyObject_GC_Del;
+ }
+ /* else they didn't agree about gc, and there isn't something
+ * obvious to be done -- the type is on its own.
+ */
}
}
inherit_slots(type, (PyTypeObject *)b);
}
+ /* Sanity check for tp_free. */
+ if (PyType_IS_GC(type) && (type->tp_flags & Py_TPFLAGS_BASETYPE) &&
+ (type->tp_free == NULL || type->tp_free == PyObject_Del)) {
+ /* This base class needs to call tp_free, but doesn't have
+ * one, or its tp_free is for non-gc'ed objects.
+ */
+ PyErr_Format(PyExc_TypeError, "type '%.100s' participates in "
+ "gc and is a base type but has inappropriate "
+ "tp_free slot",
+ type->tp_name);
+ goto error;
+ }
+
/* if the type dictionary doesn't contain a __doc__, set it from
the tp_doc slot.
*/