--- libev/ev.c	2010/01/26 04:19:37	1.326
+++ libev/ev.c	2010/02/14 19:09:04	1.327
@@ -2510,7 +2510,7 @@
     return;
 
   assert (("libev: ev_io_start called with negative fd", fd >= 0));
-  assert (("libev: ev_io start called with illegal event mask", !(w->events & ~(EV__IOFDSET | EV_READ | EV_WRITE))));
+  assert (("libev: ev_io_start called with illegal event mask", !(w->events & ~(EV__IOFDSET | EV_READ | EV_WRITE))));
 
   EV_FREQUENT_CHECK;