Question

Can anyone tell me how to tackle this exception? The debugger is at an exception breakpoint and as you can see there seems to be zero actionable information about the exception. Where did it occur? Pretty sure it’s not in my code but I’m at a loss about how to proceed…

Many thanks for any help.

Edit 1:
Here’s the console contents

* Terminating app due to uncaught exception ‘NSRangeException’, reason: ‘*
-[__NSArrayM objectAtIndex:]: index 0 beyond bounds for empty array’

*** First throw call stack: (0x30ce188f 0x3627e259 0x30c2a9db 0x8d029 0x915c5 0x35723c59 0x35725ee7 0x30cb42ad 0x30c374a5 0x30c3736d 0x36ffb439 0x32917cd5 0x72e4d 0x72de8)
terminate called throwing an exception

Edit 2:
Here’s the backtrace

thread #1: tid = 0x1c03, 0x3627e238 libobjc.A.dylib`objc_exception_throw, stop reason = breakpoint 1.1

frame #0: 0x3627e238 libobjc.A.dylib`objc_exception_throw

frame #1: 0x30c2a9da CoreFoundation`-[__NSArrayM objectAtIndex:] + 270

Edit 3 (the solution):
Here’s the backtrace using the main() approach

2012-08-31 10:27:21.489 <>[820:707] Uncaught exception *** -[__NSArrayM objectAtIndex:]: index 0 beyond bounds for empty array

2012-08-31 10:27:32.908 <>[820:707] Stack trace: (

0   CoreFoundation                      0x30ce18a7 __exceptionPreprocess + 186
1   libobjc.A.dylib                     0x3627e259 objc_exception_throw + 32
2   CoreFoundation                      0x30c2a9db -[__NSArrayM objectAtIndex:] + 270
3   <>                                  0x00050ed1 __55-[SFSummaryCard retrieveAndDisplayFirstImageForString:]_block_invoke_0 + 148
4   <>                                  0x0005546d __block_global_1 + 40
5   libdispatch.dylib                   0x35723c59 _dispatch_call_block_and_release + 12
6   libdispatch.dylib                   0x35725ee7 _dispatch_main_queue_callback_4CF$VARIANT$mp + 194
7   CoreFoundation                      0x30cb42ad __CFRunLoopRun + 1268
8   CoreFoundation                      0x30c374a5 CFRunLoopRunSpecific + 300
9   CoreFoundation                      0x30c3736d CFRunLoopRunInMode + 104
10  GraphicsServices                    0x36ffb439 GSEventRunModal + 136
11  UIKit                               0x32917cd5 UIApplicationMain + 1080
12  <>                                  0x00036c01 main + 220
13  <>                                  0x00036b20 start + 40

)

The key element being: retrieveAndDisplayFirstImageForString()

Answer 1

There is a problem on Xcode 4/iOS 5 that sometimes you don’t get the exception traceback in the emulator, due to an apparent bug in the emulator’s pseudo OS. The solution is to add an explicit traceback in your main, along the lines of

@try {
    retVal = UIApplicationMain...
}
@catch (NSException* exception) {
    NSLog(@"Uncaught exception %@", exception);
    NSLog(@"Stack trace: %@", [exception callStackSymbols]);
}