From 8f1cdc65ee9db0040d031f7da6284cc72d44c9ba Mon Sep 17 00:00:00 2001
From: Benjamin Peterson <benjamin@python.org>
Date: Wed, 5 Oct 2016 23:32:09 -0700
Subject: [PATCH] ensure read size is initialized

---
 Modules/mmapmodule.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Modules/mmapmodule.c b/Modules/mmapmodule.c
index e01de441bd6..4eb9274c665 100644
--- a/Modules/mmapmodule.c
+++ b/Modules/mmapmodule.c
@@ -267,7 +267,7 @@ static PyObject *
 mmap_read_method(mmap_object *self,
                  PyObject *args)
 {
-    Py_ssize_t num_bytes, remaining;
+    Py_ssize_t num_bytes = PY_SSIZE_T_MAX, remaining;
     PyObject *result;
 
     CHECK_VALID(NULL);