How can I set a breakpoint on _NSLockError()

Question

I am trying to debug multiple threads.

 *** -[NSLock lock]: deadlock (<NSLock: 0xc388ab0> '(null)')
 *** Break on _NSLockError() to debug.

How can I debug this?

Answer 1

If you're using the Xcode debugger (which uses gdb under the hood), pause the app and in the console enter:

b _NSLockError

Then the debugger will stop the app when _NSLockError happens, which you should be able to check the backtrace.