--- a/cpdup.c
+++ b/cpdup.c
@@ -1543,7 +1543,11 @@
  */
 
 static int
+#ifdef _ST_FLAGS_PRESENT_
 xrename(const char *src, const char *dst, u_long flags)
+#else
+xrename(const char *src, const char *dst, u_long flags __unused)
+#endif
 {
     int r;