diff --git a/Objects/rangeobject.c b/Objects/rangeobject.c
index 0fee40f..f45b771 100644
--- a/Objects/rangeobject.c
+++ b/Objects/rangeobject.c
@@ -316,7 +316,7 @@
 	   calculation is also done modulo ULONG_MAX+1.
 	*/
 	it->start = (long)(start + (unsigned long)(len-1) * step);
-	it->step = (long)(-(unsigned long)step);
+	it->step = (long)(0UL-step);
 
 	return (PyObject *)it;
 }