Tests passing

Signed-off-by: Matthew A Johnson <matjoh@microsoft.com>

Author: matajoh

Include/internal/pycore_object.h

@@ -100,6 +100,15 @@ static inline void _Py_SetImmutable(PyObject *op)
 }
 #define _Py_SetImmutable(op) _Py_SetImmutable(_PyObject_CAST(op))
 
+/* _Py_ClearImmutable() should only be used during object deallocation and runtime finalization. */
+static inline void _Py_ClearImmutable(PyObject *op)
+{
+    if (op) {
+        op->ob_refcnt &= _Py_REFCNT_MASK;
+    }
+}
+#define _Py_ClearImmutable(op) _Py_ClearImmutable(_PyObject_CAST(op))
+
 #define Py_CHECKWRITE(op) ((op) && (!_Py_IsImmutable(op)))
 #define Py_REQUIREWRITE(op, msg) {if (Py_CHECKWRITE(op)) { _PyObject_ASSERT_FAILED_MSG(op, msg); }}
 

Lib/test/test_freeze.py

@@ -149,8 +149,8 @@ def test_update(self):
 
 class TestSet(BaseObjectTest):
     def __init__(self, *args, **kwargs):
-        obj = {1: self.C(), "two": self.C()}
-        BaseObjectTest.__init__(self, *args, obj={1, "two", None, True}, **kwargs)
+        obj = {1, "two", None, True}
+        BaseObjectTest.__init__(self, *args, obj=obj, **kwargs)
 
     def test_add(self):
         with self.assertRaises(NotWriteableError):

Modules/gcmodule.c

@@ -1026,6 +1026,7 @@ delete_garbage(PyThreadState *tstate, GCState *gcstate,
             inquiry clear;
             if ((clear = Py_TYPE(op)->tp_clear) != NULL) {
                 Py_INCREF(op);
+                _Py_ClearImmutable(op);
                 (void) clear(op);
                 if (_PyErr_Occurred(tstate)) {
                     _PyErr_WriteUnraisableMsg("in tp_clear of",

Objects/object.c

@@ -2625,6 +2625,7 @@ _PyObject_AssertFailed(PyObject *obj, const char *expr, const char *msg,
 void
 _Py_Dealloc(PyObject *op)
 {
+    _Py_ClearImmutable(op);
     PyTypeObject *type = Py_TYPE(op);
     destructor dealloc = type->tp_dealloc;
 #ifdef Py_DEBUG

Objects/typeobject.c

@@ -5304,6 +5304,7 @@ type_clear(PyTypeObject *type)
     PyType_Modified(type);
     PyObject *dict = lookup_tp_dict(type);
     if (dict) {
+        _Py_ClearImmutable(dict);
         PyDict_Clear(dict);
     }
     Py_CLEAR(((PyHeapTypeObject *)type)->ht_module);

Python/bytecodes.c

@@ -1969,7 +1969,6 @@ dummy_func(
             if (!Py_CHECKWRITE(owner))
             {
                 format_exc_notwriteable(tstate, frame->f_code, oparg);
-                Py_DECREF(owner);
                 goto error;
             }
             PyDictValues *values = _PyDictOrValues_GetValues(dorv);
@@ -1996,7 +1995,6 @@ dummy_func(
             if (!Py_CHECKWRITE(owner))
             {
                 format_exc_notwriteable(tstate, frame->f_code, oparg);
-                Py_DECREF(owner);
                 goto error;
             }
             assert(PyDict_CheckExact((PyObject *)dict));
@@ -2046,7 +2044,6 @@ dummy_func(
             if (!Py_CHECKWRITE(owner))
             {
                 format_exc_notwriteable(tstate, frame->f_code, oparg);
-                Py_DECREF(owner);
                 goto error;
             }
             char *addr = (char *)owner + index;