diff --git a/Modules/_pickle.c b/Modules/_pickle.c
index 93bc1c6fee7f3c..0a7e20e10592e1 100644
--- a/Modules/_pickle.c
+++ b/Modules/_pickle.c
@@ -6713,7 +6713,7 @@ _pickle_Unpickler___init___impl(UnpicklerObject *self, PyObject *file,
 
     self->stack = (Pdata *)Pdata_New();
     if (self->stack == NULL)
-        return 1;
+        return -1;
 
     self->memo_size = 32;
     self->memo = _Unpickler_NewMemo(self->memo_size);