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After upgrading to cycle 8 we've been experiencing some apparent issue with stack trace report. It is also possible that something new in our code is trigging this issue...
Nevertheless, something is crashing our app when we hide a controller and show another, which can execute a lot of different code.
We do receive always the same stack trace:
System.NullReferenceException: Object reference not set to an instance of an object
at (wrapper managed-to-native) UIKit.UIApplication:UIApplicationMain (int,string,intptr,intptr)
at UIKit.UIApplication.Main (System.String args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/src/UIKit/UIApplication.cs:79
at UIKit.UIApplication.Main (System.String args, System.String principalClassName, System.String delegateClassName) [0x00038] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/src/UIKit/UIApplication.cs:63
at XXXX.Application.Main (System.String args) [0x00009] in #####/Main.cs:87
Note : Main.cs 87 is UIApplication.Main (args, null, "AppDelegate");
=== Xamarin Studio Community ===
Version 6.1.1 (build 15)
Installation UUID: c9aeb0c6-dfdc-4b35-ae00-01c52d42790e
Mono 4.6.1 (mono-4.6.0-branch-c8sr0/abb06f1) (64-bit)
GTK+ 2.24.23 (Raleigh theme)
Package version: 406010005
=== NuGet ===
=== Xamarin.Profiler ===
=== Xamarin.Android ===
Version: 126.96.36.199 (Xamarin Studio Community)
Android SDK: /Users/XXXX/Library/Developer/Xamarin/android-sdk-macosx
Supported Android versions:
6.0 (API level 23)
SDK Tools Version: 25.1.2
SDK Platform Tools Version: 24.0.0
SDK Build Tools Version: 23.0.2
Java SDK: /usr
java version "1.7.0_71"
Java(TM) SE Runtime Environment (build 1.7.0_71-b14)
Java HotSpot(TM) 64-Bit Server VM (build 24.71-b01, mixed mode)
Android Designer EPL code available here:
=== Xamarin Android Player ===
Location: /Applications/Xamarin Android Player.app
=== Apple Developer Tools ===
Xcode 8.0 (11246)
=== Xamarin.Mac ===
Version: 188.8.131.52 (Xamarin Studio Community)
=== Xamarin.iOS ===
Version: 10.0.1.10 (Xamarin Studio Community)
Build date: 2016-10-03 15:18:44-0400
=== Build Information ===
Release ID: 601010015
Git revision: fa52f02641726146e2589ed86ec4097fbe101888
Build date: 2016-09-22 08:03:02-04
Xamarin addins: 75d65712af93d54dc39ae4c42b21dfa574859fd6
Build lane: monodevelop-lion-cycle8-sr0
=== Operating System ===
Mac OS X 10.12.0
Darwin Manuels-MBP.home 16.0.0 Darwin Kernel Version 16.0.0
Mon Aug 29 17:56:20 PDT 2016
Most likely something is happening on a different thread (e.g. async). Both the device logs and the (symbolicated) crash reports should have more details on where this happened.
It is happening on main thread and not background. For example, if we do this
public override void ViewWillAppear (bool animated)
throw new Exception("Dummy");
we will receive a System.Exception "Dummy" with no stack trace.
If we do it on Thread pool like, for example,
public async override void ViewWillAppear (bool animated)
throw new Exception("Dummy");
stack is reported as expected.
Do you have a small sample app that happens to reproduce the issue? I have written a dummy one and I was not able to do it.
We have not received the requested information. If you are still
experiencing this issue please provide all the requested information
and re-open the bug report. Thanks!