diff -r 46567fda0b29 Lib/test/test_bytes.py
--- a/Lib/test/test_bytes.py	Sat Jul 09 11:05:42 2016 +0200
+++ b/Lib/test/test_bytes.py	Sun Jul 10 01:30:07 2016 +0800
@@ -269,6 +269,7 @@
         self.assertNotIn(200, b)
         self.assertRaises(ValueError, lambda: 300 in b)
         self.assertRaises(ValueError, lambda: -1 in b)
+        self.assertRaises(ValueError, lambda: sys.maxsize+1 in b)
         self.assertRaises(TypeError, lambda: None in b)
         self.assertRaises(TypeError, lambda: float(ord('a')) in b)
         self.assertRaises(TypeError, lambda: "a" in b)
diff -r 46567fda0b29 Objects/bytes_methods.c
--- a/Objects/bytes_methods.c	Sat Jul 09 11:05:42 2016 +0200
+++ b/Objects/bytes_methods.c	Sun Jul 10 01:30:07 2016 +0800
@@ -645,7 +645,7 @@
 int
 _Py_bytes_contains(const char *str, Py_ssize_t len, PyObject *arg)
 {
-    Py_ssize_t ival = PyNumber_AsSsize_t(arg, PyExc_ValueError);
+    Py_ssize_t ival = PyNumber_AsSsize_t(arg, NULL);
     if (ival == -1 && PyErr_Occurred()) {
         Py_buffer varg;
         Py_ssize_t pos;