I have noticed that some exceptions, like NSGenericException or NSManagedObject Exceptions do not contain a lot of details in output when app crashes on iOS 11. But in the same time if I run and make it crashed on iOS 9 or 10, it will contain a lot of useful details.
For example. Same app, same crash, on iOS 11:
libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)On iOS 9-10:
2018-01-02 23:51:22.967 CafeManager[3726:130232] *** Terminating app due to uncaught exception 'NSGenericException', reason: 'Your application has presented a UIAlertController (<UIAlertController: 0x7f959a7634c0>) of style UIAlertControllerStyleActionSheet. The modalPresentationStyle of a UIAlertController with this style is UIModalPresentationPopover. You must provide location information for this popover through the alert controller's popoverPresentationController. You must provide either a sourceView and sourceRect or a barButtonItem. If this information is not known when you present the alert controller, you may provide it in the UIPopoverPresentationControllerDelegate method -prepareForPopoverPresentation.' *** First throw call stack: ( 0 CoreFoundation 0x000000010f61eb0b __exceptionPreprocess + 171 1 libobjc.A.dylib 0x000000010ec6f141 objc_exception_throw + 48 2 UIKit 0x0000000110c04d67 -[UIPopoverPresentationController presentationTransitionWillBegin] + 3291 3 UIKit 0x00000001102ac3c2 __71-[UIPresentationController _initViewHierarchyForPresentationSuperview:]_block_invoke + 2278 4 UIKit 0x00000001102a9d20 __56-[UIPresentationController runTransitionForCurrentState]_block_invoke + 426 5 UIKit 0x0000000110137853 _runAfterCACommitDeferredBlocks + 318 6 UIKit 0x000000011012481c _cleanUpAfterCAFlushAndRunDeferredBlocks + 532 7 UIKit 0x0000000110156560 _afterCACommitHandler + 137 8 CoreFoundation 0x000000010f5c4717 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23 9 CoreFoundation 0x000000010f5c4687 __CFRunLoopDoObservers + 391 10 CoreFoundation 0x000000010f5a9720 __CFRunLoopRun + 1200 11 CoreFoundation 0x000000010f5a9016 CFRunLoopRunSpecific + 406 12 GraphicsServices 0x0000000114cc1a24 GSEventRunModal + 62 13 UIKit 0x000000011012b134 UIApplicationMain + 159 14 CafeManager 0x000000010dd37747 main + 55 15 libdyld.dylib 0x0000000113d1c65d start + 1 16 ??? 0x0000000000000001 0x0 + 1 ) libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)
As you can see, it really makes the difference. What have I missed? Any debugger settings or is it iOS 11-related issue?
Issue was resolved by enabling OS_ACTIVITY_MODE variable. I believe I disabled it in XCode 8 to prevent unwanted output.
Select from Xcode menu Product -> Scheme -> Edit Scheme.. Select the Run scheme and look under Arguments. If you see the OS_ACTIVITY_MODE variable checked, deselect it.