Index: include/asterisk/linkedlists.h
===================================================================
--- include/asterisk/linkedlists.h	(revision 328266)
+++ include/asterisk/linkedlists.h	(working copy)
@@ -854,7 +854,9 @@
 				(head)->last = curelm;				\
 		} \
 	}								\
-	(elm)->field.next = NULL;                                       \
+	if (__res) { \
+		(__res)->field.next = NULL; \
+	} \
 	(__res); \
 })