diff --git a/lib/gssapi/gssapi/gssapi_krb5.h b/lib/gssapi/gssapi/gssapi_krb5.h
index 6841f423b..f4a5fc7d6 100644
--- a/lib/gssapi/gssapi/gssapi_krb5.h
+++ b/lib/gssapi/gssapi/gssapi_krb5.h
@@ -62,6 +62,7 @@ extern gss_OID GSS_KRB5_MECHANISM;
 extern gss_OID GSS_KRB5_COPY_CCACHE_X;
 extern gss_OID GSS_KRB5_COMPAT_DES3_MIC_X;
 extern gss_OID GSS_KRB5_REGISTER_ACCEPTOR_IDENTITY_X;
+extern gss_OID GSS_KRB5_SET_DNS_CANONIZE_X;
 /* Extensions inquire context inre */
 extern gss_OID GSS_KRB5_GET_TKT_FLAGS_X;
 extern gss_OID GSS_KRB5_EXTRACT_AUTHZ_DATA_FROM_SEC_CONTEXT_X;