diff --git a/cf/roken-frag.m4 b/cf/roken-frag.m4
index 5bb773dc1..34550c7c8 100644
--- a/cf/roken-frag.m4
+++ b/cf/roken-frag.m4
@@ -169,7 +169,6 @@ AC_CHECK_FUNCS([				\
 	strunvis				\
 	strvis					\
 	strvisx					\
-	strvisx					\
 	svis					\
 	sysconf					\
 	sysctl					\