diff --git a/debug/fdelt_chk.c b/debug/fdelt_chk.c
index c5f16462ad..30f5a4bec1 100644
--- a/debug/fdelt_chk.c
+++ b/debug/fdelt_chk.c
@@ -15,6 +15,7 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <stdio.h>
 #include <sys/select.h>
 
 
@@ -22,7 +23,7 @@ long int
 __fdelt_chk (long int d)
 {
   if (d < 0 || d >= FD_SETSIZE)
-    __chk_fail ();
+    __fortify_fail ("bit out of range 0 - FD_SETSIZE on fd_set");
 
   return d / __NFDBITS;
 }