diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index efe5074..6949c90 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -1901,7 +1901,7 @@
 	/* assume encoded strings wont more than double no of chars */
 	char inbuf[MAX_PATH*2];
 	char *inbufp = inbuf;
-	Py_ssize_t insize;
+	Py_ssize_t insize = sizeof(inbuf);
 	char outbuf[MAX_PATH*2];
 	char *temp;
 #ifdef Py_WIN_WIDE_FILENAMES
@@ -1921,7 +1921,6 @@
 		PyErr_Clear();
 	}
 #endif
-	/* XXX(twouters) Why use 'et#' here at all? insize isn't used */
 	if (!PyArg_ParseTuple (args, "et#:_getfullpathname",
 	                       Py_FileSystemDefaultEncoding, &inbufp,
 	                       &insize))