-#if HAVE_POINTER_SAFE_MAKECONTEXT
-#define generator_wrapper_args_() void *ret
-#else
-#define generator_wrapper_args_() int lo, int hi
-#endif
-typedef void generator_wrapper_(generator_wrapper_args_());
-
-void *generator_new_(generator_wrapper_ *fn, size_t retsize);
-void generator_free_(void *ret);
+void *generator_new_(void (*fn)(void *), size_t retsize);
+void generator_free_(void *ret, size_t retsize);