There is an error as follows when I run my routing protocol which is added by myself:
Scheduler: Event UID not valid!

[Inferior 1 (process 9606) exited with code 01].


usually ，which always cause this problem?

When I run it in GDB.After the error appeared. When I run bt and where.
It shows:[9.454848](node 11) association successful (non-beacon enabled) [channel:11] [PAN_ID:0] [CoordAddr:9]
[9.454848](node 11) begin to transmit beacons
[9.455616](node 11) beacon transmission successful [channel:11] [PAN_ID:0]
[9.661760](node 12) sending data request command ...
[9.663008](node 12) ack for data request command received
[9.665376](node 12) association response command received
[9.665376](node 12) association successful (non-beacon enabled) [channel:11] [PAN_ID:0] [CoordAddr:10]

Transmitting data ...

Scheduler: Event UID not valid!

[Inferior 1 (process 5921) exited with code 01]
(gdb) bt
No stack.


What's wrong with it?
Please help me.