diff --git a/lib/krb5/krb5.h b/lib/krb5/krb5.h
index 9e1ec9685..50773dd6f 100644
--- a/lib/krb5/krb5.h
+++ b/lib/krb5/krb5.h
@@ -363,6 +363,7 @@ typedef union {
 #define KRB5_GC_FORWARDABLE		(1U << 4)
 #define KRB5_GC_NO_TRANSIT_CHECK	(1U << 5)
 #define KRB5_GC_CONSTRAINED_DELEGATION	(1U << 6)
+#define KRB5_GC_CANONICALIZE		(1U << 7)
 
 /* constants for compare_creds (and cc_retrieve_cred) */
 #define KRB5_TC_DONT_MATCH_REALM	(1U << 31)