Don't empty trashcan unless object is GC'd

Author: markshannon

Objects/object.c

@@ -3150,10 +3150,11 @@ void
 _Py_Dealloc(PyObject *op)
 {
     PyTypeObject *type = Py_TYPE(op);
+    unsigned long gc_flags = type->tp_flags & Py_TPFLAGS_HAVE_GC;
     destructor dealloc = type->tp_dealloc;
     PyThreadState *tstate = _PyThreadState_GET();
     intptr_t margin = _Py_RecursionLimit_GetMargin(tstate);
-    if (margin < 2 && PyObject_IS_GC(op)) {
+    if (margin < 2 && gc_flags) {
         _PyTrash_thread_deposit_object(tstate, (PyObject *)op);
         return;
     }
@@ -3199,7 +3200,7 @@ _Py_Dealloc(PyObject *op)
     Py_XDECREF(old_exc);
     Py_DECREF(type);
 #endif
-    if (tstate->delete_later && margin >= 4) {
+    if (tstate->delete_later && margin >= 4 && gc_flags) {
         _PyTrash_thread_destroy_chain(tstate);
     }
 }