diff -r feed6d2097b1 Objects/listobject.c
--- a/Objects/listobject.c      Wed Sep 14 15:19:42 2011 +0200
+++ b/Objects/listobject.c      Thu Sep 15 19:27:36 2011 +0200
@@ -551,9 +551,9 @@
     PyObject *elem;
     if (n < 0)
         n = 0;
+    if (Py_SIZE(a) > 0 && n > PY_SSIZE_T_MAX/Py_SIZE(a))
+        return PyErr_NoMemory();
     size = Py_SIZE(a) * n;
-    if (n && size/n != Py_SIZE(a))
-        return PyErr_NoMemory();
     if (size == 0)
         return PyList_New(0);
     np = (PyListObject *) PyList_New(size);