diff --git a/lib/stdlib/stdlib.mk b/lib/stdlib/stdlib.mk
index cdf3d29..4ff405f 100644
--- a/lib/stdlib/stdlib.mk
+++ b/lib/stdlib/stdlib.mk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are met:
@@ -41,6 +41,7 @@
 			strcmp.c			\
 			strlen.c			\
 			strncmp.c			\
+			strnlen.c			\
 			subr_prf.c)
 
 INCLUDES	+=	-Iinclude/lib/stdlib		\