diff -r 0308f97616a3 Modules/posixmodule.c
--- a/Modules/posixmodule.c	Fri Sep 16 13:54:05 2016 -0400
+++ b/Modules/posixmodule.c	Mon Sep 19 00:53:15 2016 +0200
@@ -920,7 +920,7 @@ path_converter(PyObject *o, void *p)
 
     if (is_unicode) {
 #ifdef MS_WINDOWS
-        wide = PyUnicode_AsWideCharString(o, &length);
+        wide = PyUnicode_AsUnicodeAndSize(o, &length);
         if (!wide) {
             goto exit;
         }