Fix zero-length corner case for iterating over a mutating deque.
diff --git a/Misc/NEWS b/Misc/NEWS
index 76ed61e..4df89da 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -129,6 +129,9 @@
 
 - Added support for linking the bsddb module against BerkeleyDB 4.5.x.
 
+- Modifying an empty deque during iteration now raises RuntimeError
+  instead of StopIteration.
+
 
 Library
 -------