iOS 5.0 ignoring NSSetUncaughtExceptionHandler? - exception

Question

I've noticed some strange behavior in iOS 5: NSSetUncaughtExceptionHandler() doesn't seem to do anything anymore.
I have the following code:
static NSString* documentsDirectory()
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *basePath = ([paths count] > 0) ? [paths objectAtIndex:0] : nil;
return basePath;
}
static void handleException(NSException *exception)
{
// Write something to the documents dir
NSString* path = [documentsDirectory() stringByAppendingPathComponent:#"crashlog.txt"];
NSString* str = #"Handled exception";
NSError* err;
if(![str writeToFile:path atomically:YES encoding:NSUTF8StringEncoding error:&err])
{
NSLog(#"Failed to write to file");
}
NSLog(#"Handled exception");
}
#implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
NSSetUncaughtExceptionHandler(&handleException);
[NSException raise:#"Test" format:#"Testing"];
...
}
The above code works on any device or simulator running 4.x or earlier. However, when I run it on the 5.0 simulator, the exception handler doesn't get called (doesn't write the file to the documents dir, doesn't log, and doesn't trigger if I set a breakpoint inside the handler).
Unfortunately, I don't have a 5.0 device available for testing, so I'm hoping someone could confirm that it's broken on 5.0 so I can file a bug report (or correct me, if there's a problem with my code).

Answer 1

Use iOS 6.0 SDK, build and run it on simulator 5.0! It works!
//////Code:
static NSString* documentsDirectory()
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *basePath = ([paths count] > 0) ? [paths objectAtIndex:0] : nil;
return basePath;
}
static void handleException(NSException *exception)
{
// Write something to the documents dir
NSString* path = [documentsDirectory() stringByAppendingPathComponent:#"crashlog.txt"];
NSString* str = #"Handled exception";
NSError* err;
if(![str writeToFile:path atomically:YES encoding:NSUTF8StringEncoding error:&err])
{
NSLog(#"Failed to write to file");
}
NSLog(#"Handled exception");
}
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
NSSetUncaughtExceptionHandler(&handleException);
[NSException raise:#"Test" format:#"Testing"];
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
// Override point for customization after application launch.
self.viewController = [[[NSSetUncaughtExceptionHandlerTestViewController alloc] initWithNibName:#"NSSetUncaughtExceptionHandlerTestViewController" bundle:nil] autorelease];
self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];
return YES;
}
//////Terminal log:
2012-10-09 20:06:24.726 NSSetUncaughtExceptionHandlerTest[7815:c07] Handled exception
2012-10-09 20:06:24.727 NSSetUncaughtExceptionHandlerTest[7815:c07] *** Terminating app due to uncaught exception 'Test', reason: 'Testing'
*** First throw call stack:
(0x14a4052 0xea4d0a 0x144ca78 0x144c9e9 0x29d7 0x129d6 0x138a6 0x22743 0x231f8 0x16aa9 0x138efa9 0x14781c5 0x13dd022 0x13db90a 0x13dadb4 0x13daccb 0x132a7 0x14a9b 0x28b2 0x27e5)
terminate called throwing an exception(lldb)

Answer 2

I'm seeing the same thing. It works on my iPad, but not in the simulator. If someone confirms on the phone, please feel free to edit this answer to reflect that.