diff --git a/src/libraries/libisc-new/src/isc_output.c b/src/libraries/libisc-new/src/isc_output.c
index 032c12798b45085ed80de79ce696b5cb1da1cb18..3081b374cc98769c14fb391c674cb3fb69b23646 100644
--- a/src/libraries/libisc-new/src/isc_output.c
+++ b/src/libraries/libisc-new/src/isc_output.c
@@ -19,11 +19,6 @@
 #include "intern.h"
 
 
-/*
- * External function declarations
- */
-extern char *strerror(int);
-
 
 void isc_flush(IscSession *scb)
 {