diff --git a/lib/sl/sl.c b/lib/sl/sl.c
index b6e4fd68b..bc157483f 100644
--- a/lib/sl/sl.c
+++ b/lib/sl/sl.c
@@ -103,7 +103,12 @@ sl_help (SL_cmd *cmds, int argc, char **argv)
     }
 }
 
-#ifndef HAVE_READLINE
+#ifdef HAVE_READLINE
+
+char *readline(char *prompt);
+void add_history(char *p);
+
+#else
 
 static char *
 readline(char *prompt)