1 files changed, 4 insertions, 0 deletions
diff --git a/ev.c b/ev.c
index 7af2358..83c643a 100644
--- a/ev.c
+++ b/ev.c
@@ -796,6 +796,8 @@ timers_reify (EV_P)
     {
       struct ev_timer *w = timers [0];
 
+      assert (("inactive timer on timer heap detected", ev_is_active (w)));
+
       /* first reschedule or stop timer */
       if (w->repeat)
         {
@@ -817,6 +819,8 @@ periodics_reify (EV_P)
     {
       struct ev_periodic *w = periodics [0];
 
+      assert (("inactive timer on periodic heap detected", ev_is_active (w)));
+
       /* first reschedule or stop timer */
       if (w->interval)
         {