Bug 59691 - MTOUCH : error MT2001: Could not link assemblies. Reason: Object reference not set to an instance of an object
Summary: MTOUCH : error MT2001: Could not link assemblies. Reason: Object reference no...
Status: RESOLVED DUPLICATE of bug 59620
Alias: None
Product: iOS
Classification: Xamarin
Component: Mono runtime / AOT compiler ()
Version: XI 11.0 (xcode9)
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Zoltan Varga
Depends on:
Reported: 2017-09-22 12:58 UTC by Andrii Kaplanovskyi
Modified: 2017-09-22 13:43 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

Build log (3.97 MB, text/rtf)
2017-09-22 12:58 UTC, Andrii Kaplanovskyi

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.

Please create a new report on Developer Community or GitHub with your current version information, steps to reproduce, and relevant error messages or log files if you are hitting an issue that looks similar to this resolved bug and you do not yet see a matching new report.

Related Links:

Description Andrii Kaplanovskyi 2017-09-22 12:58:37 UTC
Created attachment 24890 [details]
Build log

I get 'MTOUCH : error MT2001: Could not link assemblies. Reason: Object reference not set to an instance of an object'

after I installed all the latest updated for Visual Studio: 

=== Visual Studio Community 2017 for Mac ===

Version 7.1.5 (build 2)
Installation UUID: 28c91529-4015-40eb-8772-f3cc31b7a485
	Mono (d15-3/14f2c81) (64-bit)
	GTK+ 2.24.23 (Raleigh theme)

	Package version: 502000224

=== NuGet ===


=== .NET Core ===

Runtime: /usr/local/share/dotnet/dotnet
Runtime Versions:
SDK: /usr/local/share/dotnet/sdk/1.0.3/Sdks
SDK Version: 1.0.3
MSBuild SDKs: /Library/Frameworks/Mono.framework/Versions/5.2.0/lib/mono/msbuild/15.0/bin/Sdks

=== Xamarin.Profiler ===

Version: 1.5.5
Location: /Applications/Xamarin Profiler.app/Contents/MacOS/Xamarin Profiler

=== Apple Developer Tools ===

Xcode 8.2.1 (11766.1)
Build 8C1002

=== Xamarin.Mac ===

Version: (Visual Studio Community)

=== Xamarin.Android ===

Version: (Visual Studio Community)
Android SDK: /Users/dcsl/Library/Developer/Xamarin/android-sdk-macosx
	Supported Android versions:
		2.3   (API level 10)
		4.0.3 (API level 15)
		4.4   (API level 19)
		5.0   (API level 21)
		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.iOS ===

Version: (Visual Studio Community)
Hash: 152b654a
Branch: xcode9
Build date: 2017-09-15 02:25:56-0400

=== Xamarin Inspector ===

Version: 1.3.1
Hash: cbc48dd
Branch: 1.3-release
Build date: Thu, 21 Sep 2017 19:52:53 GMT
Client compatibility: 1

=== Build Information ===

Release ID: 701050002
Git revision: 7afedcaef8e7542e70e3cf8f9bdb26938b8c0876
Build date: 2017-09-15 08:39:58-04
Xamarin addins: 3262aadf811a18c12eac6742532d052b0139a808
Build lane: monodevelop-lion-d15-3-xcode9

=== Operating System ===

Mac OS X 10.11.6
Darwin 15.6.0 Darwin Kernel Version 15.6.0
    Sun Jun  4 21:43:07 PDT 2017
    root:xnu-3248.70.3~1/RELEASE_X86_64 x86_64
Comment 1 John Miller [MSFT] 2017-09-22 13:17:34 UTC
Hi Andrii,

This looks similar to the problem report in Bug 59620. 

Xamarin.iOS 11.0 requires that you update to Xcode 9, however, there is another fix for the root issue in Bug 59620 that did not make it in time for the 11.0 release. 

The fix is in our beta channel. Since you are still using Xcode 8.2.1, you can switch to the beta channel in VS for Mac and install Xamarin.iOS 10.14 to workaround that build issue. 

If you need to build for iOS 11, you'll have to update to Xcode 9. However, you may still hit this same error message for the reasons noted here: https://bugzilla.xamarin.com/show_bug.cgi?id=59620#c5

To fix the root issue here _and_ work with Xamarin.iOS 11 and Xcode 9, you'll need the next version that includes Xcode 9 support and the fix which will be released soon. Please keep an eye on Bug 59620 for when Brendan can comment that it's released.
Comment 2 John Miller [MSFT] 2017-09-22 13:19:35 UTC

*** This bug has been marked as a duplicate of bug 59620 ***
Comment 3 Andrii Kaplanovskyi 2017-09-22 13:43:38 UTC
Thank you very much, installing Xamarin.iOS 10.14 helped!