diff --git a/cf/krb-irix.m4 b/cf/krb-irix.m4
index 88cb4cb66..16dd2227f 100644
--- a/cf/krb-irix.m4
+++ b/cf/krb-irix.m4
@@ -4,6 +4,7 @@ dnl
 
 dnl requires AC_CANONICAL_HOST
 AC_DEFUN(KRB_IRIX,[
+irix=no
 case "$host_os" in
 irix*) irix=yes ;;
 esac