diff --git a/Modules/mmapmodule.c b/Modules/mmapmodule.c
index 6abdc71bbb8..95d42d6dc5e 100644
--- a/Modules/mmapmodule.c
+++ b/Modules/mmapmodule.c
@@ -1050,7 +1050,7 @@ static PyObject *
 new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
 {
     struct _Py_stat_struct status;
-    int fstat_result;
+    int fstat_result = -1;
     mmap_object *m_obj;
     Py_ssize_t map_size;
     off_t offset = 0;