diff --git a/net-libs/ldns/files/ldns-1.9.0-std23-bool.patch b/net-libs/ldns/files/ldns-1.9.0-std23-bool.patch
index 264e6f8e47093..be55db9f5e160 100644
--- a/net-libs/ldns/files/ldns-1.9.0-std23-bool.patch
+++ b/net-libs/ldns/files/ldns-1.9.0-std23-bool.patch
@@ -16,3 +16,12 @@ From: Petr Menšík <pemensik@redhat.com>
  #ifndef __bool_true_false_are_defined
  # ifdef HAVE_STDBOOL_H
  #  include <stdbool.h>
+@@ -47,6 +51,8 @@
+ #  ifndef HAVE__BOOL
+ #   ifdef __cplusplus
+ typedef bool _Bool;
++#   elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
++/* _Bool is a built-in keyword since C99; no macro definition needed.  */
+ #   else
+ #    define _Bool signed char
+ #   endif