diff -r 8fbbc7c8748e Python/marshal.c
--- a/Python/marshal.c	Sat Jul 28 12:25:55 2012 +0200
+++ b/Python/marshal.c	Sat Jul 28 12:45:25 2012 +0200
@@ -121,15 +121,6 @@
     w_byte((char)((x>>24) & 0xff), p);
 }
 
-#if SIZEOF_LONG > 4
-static void
-w_long64(long x, WFILE *p)
-{
-    w_long(x, p);
-    w_long(x>>32, p);
-}
-#endif
-
 /* We assume that Python longs are stored internally in base some power of
    2**15; for the sake of portability we'll always read and write them in base
    exactly 2**15. */
@@ -219,8 +210,8 @@
 #if SIZEOF_LONG > 4
             long y = Py_ARITHMETIC_RIGHT_SHIFT(long, x, 31);
             if (y && y != -1) {
-                w_byte(TYPE_INT64, p);
-                w_long64(x, p);
+                /* Too large for TYPE_INT */
+                w_PyLong((PyLongObject*)v, p);
             }
             else
 #endif