diff --git a/lib/warnless.h b/lib/warnless.h
index ca3737859..2c619bf81 100644
--- a/lib/warnless.h
+++ b/lib/warnless.h
@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -33,8 +33,6 @@ unsigned short curlx_ultous(unsigned long ulnum);
 
 unsigned char curlx_ultouc(unsigned long ulnum);
 
-int curlx_ultosi(unsigned long ulnum);
-
 int curlx_uztosi(size_t uznum);
 
 curl_off_t curlx_uztoso(size_t uznum);