Xamarin Android build failing because of Linking=Sdk Assemblies Only

[HelenMamalaki]

I get the an "MSB4018: The "LinkAssemblies" task failed unexpectedly" error when building my Xamarin Android app. I am compiling using the Latest Platform Android 7.0, and Target Android version is the same. I cannot replicate on my local machine.

Full error from build script:
C:\Program Files (x86)\MSBuild\Xamarin\Android\Xamarin.Android.Common.targets (1616, 5)
C:\Program Files (x86)\MSBuild\Xamarin\Android\Xamarin.Android.Common.targets(1616,5): Error MSB4018: The "LinkAssemblies" task failed unexpectedly.
Xamarin.Android.XamarinAndroidException: error XA2006: Reference to metadata item 'Mono.Security.Cryptography.SymmetricTransform' (defined in 'System.Core, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e') from 'System.Core, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e' could not be resolved. ---> Mono.Cecil.ResolutionException: Failed to resolve Mono.Security.Cryptography.SymmetricTransform
at Mono.Linker.Steps.MarkStep.MarkType(TypeReference reference)
at MonoDroid.Tuner.MonoDroidMarkStep.MarkType(TypeReference reference)
at Mono.Linker.Steps.MarkStep.MarkType(TypeReference reference)
at MonoDroid.Tuner.MonoDroidMarkStep.MarkType(TypeReference reference)
at Mono.Linker.Steps.MarkStep.InitializeType(TypeDefinition type)
at Mono.Linker.Steps.MarkStep.InitializeAssembly(AssemblyDefinition assembly)
at Mono.Linker.Steps.MarkStep.Initialize()
at Mono.Linker.Steps.MarkStep.Process(LinkContext context)
at Mono.Linker.Pipeline.Process(LinkContext context)
at MonoDroid.Tuner.Linker.Process(LinkerOptions options, LinkContext& context)
at Xamarin.Android.Tasks.LinkAssemblies.Execute()
--- End of inner exception stack trace ---
at Xamarin.Android.Diagnostic.Error(Int32 code, Exception innerException, String message, Object[] args)
at Xamarin.Android.Tasks.LinkAssemblies.Execute()
at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
at Microsoft.Build.BackEnd.TaskBuilder.d__26.MoveNext()
Process 'msbuild.exe' exited with code '1'.

[yacaovsnc]

Thank you for reporting this issue. We are working on updating the hosted build VM to work with latest Xamarin Android.

Duplicate of #3191.

Update: sorry after reading the issue a little bit more, I see the two issues report different exceptions. While updating the build VM may solve the issue, I will leave both open and track as separate issues for now. Thanks.

[madhurig]

The Linker error you are seeing is due the hosted build VMs not having Xamarin.Android 7.0 support though the Android SDK 24 is installed. We will be updating them early next year after the holidays.
I see this other issue xamarin/app-crm#110 which was resolved by targeting 6.0 as well.

Thanks,
Madhuri

[shortstuffsushi]

@madhurig could you please add a comment noting why you close issues in the future? By digging through linked issues, I saw that it was fixed, but it's not clear in this issue.

[madhurig]

@shortstuffsushi : Sure. The hosted build VMs were updated with Xamarin.Android 7.0 support in the last week of December.

[shortstuffsushi]

@madhurig in this instance, I already saw it. I mean to say, in the future, please provide context when closing an issue for those of us watching.

[danieljaguiar]

@madhurig I am getting this error now. Does this one came back? I am using 7.1...

[madhurig]

@danieljaguiar: We were tracking this issue for Android 7. If you are seeing an issue with 7.1, please open a new issue with the build logs.

[anobik]

Now I am facing this issue

Severity Code Description Project File Line Suppression State
Error The "LinkAssemblies" task failed unexpectedly.
Mono.Linker.MarkException: Error processing method: 'System.Linq.ParallelQuery`1 System.Linq.ParallelQuery::Cast()' in assembly: 'System.Core.dll' ---> Mono.Cecil.ResolutionException: Failed to resolve System.Void System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverageAttribute::.ctor()
at Mono.Linker.Steps.MarkStep.HandleUnresolvedMethod(MethodReference reference)
at Mono.Linker.Steps.MarkStep.MarkMethod(MethodReference reference)
at Mono.Linker.Steps.MarkStep.MarkCustomAttribute(CustomAttribute ca)
at Mono.Linker.Steps.MarkStep.MarkCustomAttributes(ICustomAttributeProvider provider)
at Mono.Linker.Steps.MarkStep.ProcessMethod(MethodDefinition method)
at Mono.Linker.Steps.MarkStep.ProcessQueue()
--- End of inner exception stack trace ---
at Mono.Linker.Steps.MarkStep.ProcessQueue()
at Mono.Linker.Steps.MarkStep.ProcessEntireQueue()
at Mono.Linker.Steps.MarkStep.Process()
at Mono.Linker.Steps.MarkStep.Process(LinkContext context)
at Mono.Linker.Pipeline.Process(LinkContext context)
at MonoDroid.Tuner.Linker.Process(LinkerOptions options, ILogger logger, LinkContext& context)
at Xamarin.Android.Tasks.LinkAssemblies.Execute(DirectoryAssemblyResolver res)
at Xamarin.Android.Tasks.LinkAssemblies.Execute()
at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
at Microsoft.Build.BackEnd.TaskBuilder.d__26.MoveNext()

VS 2017Enterprise
Android 7.1
Dot Net Framework 4.6.2

Please suggest a way out.

[madhurig]

@anobik: This issue is a year old. Please open a new issue.

[anobik]

@madhurig already raised one

#6834

Please let me know if any more details required.

Thanks,
Anobik