diff --git a/src/libsystemd-network/ndisc-option.h b/src/libsystemd-network/ndisc-option.h
index d92ff6813c..2a10af5e47 100644
--- a/src/libsystemd-network/ndisc-option.h
+++ b/src/libsystemd-network/ndisc-option.h
@@ -333,7 +333,6 @@ static inline int ndisc_option_add_encrypted_dns(
 }
 static inline int ndisc_option_set_encrypted_dns(
                 Set **options,
-                size_t offset,
                 sd_dns_resolver *res,
                 usec_t lifetime,
                 usec_t valid_until) {