I've been struggling with an weird issue for some time now. When running my app with the iOS Simulator initially closed it launches correctly. But if I then run it again without closing the simulator it crashes and just prints (lldb) in the error log. If I then run it again (without closing the simulator) it launches correctly. And if I do the same again it crashes. So it seems to be every second time. It works when using a iOS device and I have a college with the exact same project who doesn't experience this problem in the iOS Simulator. What I've tried is cleaning, reset contents and settings, manually removing the app, restarting my computer and reinstalling Xcode.
There's an issue with OS X 10.8.4 that causes random simulator crashes.
https://devforums.apple.com/message/817179#817179
A couple of workarounds have been suggested, including switching to GDB. See here:
We have found the issue. It is a process killing race condition in "debugserver" when it is killing the application it is debugging which causes this problem to occur.
The work around that should work for all folks is to kill the app first, wait for it to go away, then hit CMD+R. The quick turn around of just pressing CMD+R is now showing this thread race condition more often in 10.8.4.
Apple resolved this issue in June 13th, 2013 build:
Yes, I meet it too. In Product -> edit scheme change the debugger from lldb to gdb. Can simply solve it. Hope Apple can fix it asap.
来源：https://stackoverflow.com/questions/16957602/random-lldb-crashes-in-ios-simulator-on-mac-os-x-10-8-4