diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 146dae0..e2efabd 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -2740,4 +2740,6 @@
 }
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */
 
+int mbedtls_ssl_tls13_finalize_write_client_hello(mbedtls_ssl_context *ssl);
+
 #endif /* ssl_misc.h */