Index: Modules/readline.c
--- Modules/readline.c.orig
+++ Modules/readline.c
@@ -1464,6 +1464,8 @@ static struct PyModuleDef readlinemodule = {
 };
 
 
+/* XXX hack around the visibility attribute being lost when compiled with c99 or c11 */
+#undef __attribute__
 PyMODINIT_FUNC
 PyInit_readline(void)
 {