NSRangeException occurs when I perform [receiveMessage:]

[chenweiyj]

Hi all,
I have met a bug that sometimes may happen sometimes may not when calling [receiveMessage:].

I perform an async request to server to get a list of messages of 50 items. And I use a for loop to call [self receiveMessage:message];, and then an exception occurs as follows:

2014-08-02 17:37:08.157 Foyo[3355:4607] *** Terminating app due to uncaught exception 'NSRangeException', reason: '-[UITableView _contentOffsetForScrollingToRowAtIndexPath:atScrollPosition:]: row (25) beyond bounds (25) for section (0).'
*** First throw call stack:
(0x2dc63f83 0x384deccf 0x2dc63ec5 0x306a0a41 0x306a07cb 0xf43ed 0xf4193 0xf921d 0xfea67 0xfaa9b 0x2e679f35 0x2e5a83c7 0x2e5985ab 0x2e63c76d 0x389cc293 0x389cdad7 0x389cdd29 0x38b08bd3 0x38b08a98)
libc++abi.dylib: terminating with uncaught exception of type NSException

Anyone could help me?