title: Xamarin.iOS MT2002 Failed to resolve BindingImplAttribute on Xamarin 11.9.1
body: <p>Xamarin.iOS app build in AppCenter fails with the following error.</p>
  
  <pre><code>  MTOUCH : error MT2002: 
    Failed to resolve "System.Void.ObjCRuntime.BindingImplAttribute::.ctor(ObjCRuntime.BindingImplOptions)" 
    reference from "Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065"
  </code></pre>
  
  <p>Tried using Mono 5.8.1 and Xamarin iOS with XCode 9.3 (and 9.3.1) - same problem. 
  The project does not reference Lottie (<a href="https://github.com/martijn00/LottieXamarin/issues/159" rel="nofollow noreferrer">see issue on Github</a>), but has lots of other references.</p>
  
  <p>Adding <code>-v -v -v -v</code> to mtouch arguments shows this stack:</p>
  
  <pre><code>     /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/bin/mtouch --cache=/Users/vsts/agent/2.133.3/work/1/s/co.MyApp.ios/obj/iPhone/AppStore/mtouch-cache --dev=/Users/vsts/agent/2.133.3/work/1/s/co.MyApp.ios/bin/iPhone/AppStore/co.MyApp.ios.app --executable=co.MyApp.ios --linksdkonly --sdkroot=/Applications/Xcode_9.3.1.app/Contents/Developer --sdk=11.3 --targetver=10.0 --aot-options=-O=-float32 --http-message-handler=HttpClientHandler --abi=armv7,arm64 --symbollist=/Users/vsts/agent/2.133.3/work/1/s/co.MyApp.ios/obj/iPhone/AppStore/mtouch-symbols.list --dsym=no -v -v -v -v -r=/Users/vsts/agent/2.133.3/work/1/s/Vendor/co.MyApp.Red5.Timeshift.iOS/bin/Release/co.MyApp.Red5.Timeshift.iOS.dll -r=/Users/vsts/agent/2.133.3/work/1/s/packages/DT.Xamarin.Red5Pro.Streaming.iOS.4.6.0-beta1/lib/Xamarin.iOS10/DT.Xamarin.Red5Pro.Streaming.iOS.dll -r=/Users/vsts/agent/2.133.3/work/1/s/packages/Fabric.1.4/lib/Xamarin.iOS10/FabricSdk.dll -r=/Users/vsts/agent/2.133.3/work/1/s/packages/Fabric.1.4/lib/Xamarin...
      MTOUCH : error MT2002: Failed to resolve "System.Void ObjCRuntime.BindingImplAttribute::.ctor(ObjCRuntime.BindingImplOptions)" reference from "Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065" [/Users/vsts/agent/2.133.3/work/1/s/co.MyApp.ios/co.MyApp.iOS.csproj]
        --- inner exception
        Mono.Cecil.ResolutionException: Failed to resolve System.Void ObjCRuntime.BindingImplAttribute::.ctor(ObjCRuntime.BindingImplOptions)
          at Mono.Linker.Steps.MarkStep.HandleUnresolvedMethod (Mono.Cecil.MethodReference reference) [0x0001b] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:1573 
          at Mono.Linker.Steps.MarkStep.MarkMethod (Mono.Cecil.MethodReference reference) [0x00063] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:1291 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkMethod (Mono.Cecil.MethodReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:140 
          at Xamarin.Linker.Steps.CoreMarkStep.MarkMethod (Mono.Cecil.MethodReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:212 
          at MonoTouch.Tuner.MonoTouchMarkStep.MarkMethod (Mono.Cecil.MethodReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:98 
          at Mono.Linker.Steps.MarkStep.MarkCustomAttribute (Mono.Cecil.CustomAttribute ca) [0x00019] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:280 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkCustomAttribute (Mono.Cecil.CustomAttribute ca) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:162 
          at Mono.Linker.Steps.MarkStep.MarkCustomAttributes (Mono.Cecil.ICustomAttributeProvider provider) [0x00035] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:261 
          at Mono.Linker.Steps.MarkStep.MarkField (Mono.Cecil.FieldReference reference) [0x0005e] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:559 
          at Mono.Linker.Steps.MarkStep.MarkFields (Mono.Cecil.TypeDefinition type, System.Boolean includeStatic, System.Boolean markBackingFieldsOnlyIfPropertyMarked) [0x00083] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:1230 
          at Mono.Linker.Steps.MarkStep.ApplyPreserveInfo (Mono.Cecil.TypeDefinition type) [0x00041] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:1179 
          at Mono.Linker.Steps.MarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00203] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:666 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:71 
          at Xamarin.Linker.Steps.CoreMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00046] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:156 
          at MonoTouch.Tuner.MonoTouchMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:84 
          at Mono.Linker.Steps.MarkStep.MarkWithResolvedScope (Mono.Cecil.TypeReference type) [0x000a4] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:480 
          at Mono.Linker.Steps.MarkStep.MarkIfType (Mono.Cecil.CustomAttributeArgument argument) [0x00088] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:448 
          at Mono.Linker.Steps.MarkStep.MarkCustomAttributeProperty (Mono.Cecil.CustomAttributeNamedArgument namedArgument, Mono.Cecil.TypeDefinition attribute) [0x00032] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:365 
          at Mono.Linker.Steps.MarkStep.MarkCustomAttributeProperties (Mono.Cecil.CustomAttribute ca, Mono.Cecil.TypeDefinition attribute) [0x00027] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:355 
          at Mono.Linker.Steps.MarkStep.MarkCustomAttribute (Mono.Cecil.CustomAttribute ca) [0x00054] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:292 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkCustomAttribute (Mono.Cecil.CustomAttribute ca) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:162 
          at Mono.Linker.Steps.MarkStep.MarkCustomAttributes (Mono.Cecil.ICustomAttributeProvider provider) [0x00035] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:261 
          at Mono.Linker.Steps.MarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x000ad] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:626 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:71 
          at Xamarin.Linker.Steps.CoreMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00046] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:156 
          at MonoTouch.Tuner.MonoTouchMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:84 
          at Mono.Linker.Steps.MarkStep.MarkInterfaceImplementation (Mono.Cecil.TypeDefinition type, Mono.Cecil.InterfaceImplementation iface) [0x00009] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:1578 
          at Mono.Linker.Steps.MarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00163] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:650 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:71 
          at Xamarin.Linker.Steps.CoreMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00046] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:156 
          at MonoTouch.Tuner.MonoTouchMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:84 
          at Mono.Linker.Steps.MarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00093] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:624 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:71 
          at Xamarin.Linker.Steps.CoreMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00046] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:156 
          at MonoTouch.Tuner.MonoTouchMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:84 
          at Mono.Linker.Steps.MarkStep.MarkField (Mono.Cecil.FieldReference reference) [0x00051] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:558 
          at Mono.Linker.Steps.MarkStep.MarkFields (Mono.Cecil.TypeDefinition type, System.Boolean includeStatic, System.Boolean markBackingFieldsOnlyIfPropertyMarked) [0x00083] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:1230 
          at Mono.Linker.Steps.MarkStep.ApplyPreserveInfo (Mono.Cecil.TypeDefinition type) [0x00041] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:1179 
          at Mono.Linker.Steps.MarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00203] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:666 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:71 
          at Xamarin.Linker.Steps.CoreMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00046] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:156 
          at MonoTouch.Tuner.MonoTouchMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:84 
          at Mono.Linker.Steps.MarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x000a0] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:625 
          at Xamarin.Linker.Steps.MobileMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:71 
          at Xamarin.Linker.Steps.CoreMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00046] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:156 
          at MonoTouch.Tuner.MonoTouchMarkStep.MarkType (Mono.Cecil.TypeReference reference) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:84 
          at Mono.Linker.Steps.MarkStep.InitializeType (Mono.Cecil.TypeDefinition type) [0x0005b] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:101 
          at Mono.Linker.Steps.MarkStep.InitializeType (Mono.Cecil.TypeDefinition type) [0x00023] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:95 
          at Mono.Linker.Steps.MarkStep.InitializeAssembly (Mono.Cecil.AssemblyDefinition assembly) [0x00033] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:85 
          at Mono.Linker.Steps.MarkStep.Initialize () [0x00016] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:75 
          at Mono.Linker.Steps.MarkStep.Process (Mono.Linker.LinkContext context) [0x00008] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker.Steps/MarkStep.cs:68 
          at Xamarin.Linker.Steps.MobileMarkStep.Process (Mono.Linker.LinkContext context) [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MobileMarkStep.cs:33 
          at Xamarin.Linker.Steps.CoreMarkStep.Process (Mono.Linker.LinkContext context) [0x00017] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/CoreMarkStep.cs:26 
          at MonoTouch.Tuner.MonoTouchMarkStep.Process (Mono.Linker.LinkContext context) [0x0001d] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/linker/MonoTouch.Tuner/MonoTouchMarkStep.cs:36 
          at Mono.Linker.Pipeline.Process (Mono.Linker.LinkContext context) [0x0001e] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/external/mono/external/linker/linker/Mono.Linker/Pipeline.cs:127 
          at MonoTouch.Tuner.Linker.Process (MonoTouch.Tuner.LinkerOptions options, MonoTouch.Tuner.MonoTouchLinkContext&amp; context, System.Collections.Generic.List`1[Mono.Cecil.AssemblyDefinition]&amp; assemblies) [0x000e0] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Tuning.cs:82 
        ---
          at MonoTouch.Tuner.Linker.Process (MonoTouch.Tuner.LinkerOptions options, MonoTouch.Tuner.MonoTouchLinkContext&amp; context, System.Collections.Generic.List`1[Mono.Cecil.AssemblyDefinition]&amp; assemblies) [0x00257] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Tuning.cs:106 
          at Xamarin.Bundler.Target.LinkAssemblies (System.Collections.Generic.List`1[Mono.Cecil.AssemblyDefinition]&amp; assemblies, System.String output_dir, System.Collections.Generic.IEnumerable`1[T] sharedCodeTargets) [0x0029f] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Target.cs:496 
          at Xamarin.Bundler.Target.ManagedLink () [0x005c5] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Target.cs:619 
          at Xamarin.Bundler.Target.ProcessAssemblies () [0x000c2] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Target.cs:807 
          at Xamarin.Bundler.Application.ProcessAssemblies () [0x0002f] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Application.cs:1409 
          at Xamarin.Bundler.Application.BuildManaged () [0x00001] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Application.cs:836 
          at Xamarin.Bundler.Application+&lt;&gt;c.&lt;BuildAll&gt;b__138_1 (Xamarin.Bundler.Application v) [0x00000] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Application.cs:784 
          at System.Collections.Generic.List`1[T].ForEach (System.Action`1[T] action) [0x00024] in &lt;e22c1963d07746cd9708456620d50e1a&gt;:0 
          at Xamarin.Bundler.Application.BuildAll () [0x00050] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/Application.cs:784 
          at Xamarin.Bundler.Driver.Main2 (System.String[] args) [0x00488] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/mtouch.cs:1408 
          at Xamarin.Bundler.Driver.Main (System.String[] args) [0x00015] in /Users/builder/data/lanes/5909/f62de472/source/xamarin-macios/tools/mtouch/mtouch.cs:933 
      Done Building Project "/Users/vsts/agent/2.133.3/work/1/s/co.MyApp.ios/co.MyApp.iOS.csproj" (Rebuild target(s)) -- FAILED.
      Done Building Project "/Users/vsts/agent/2.133.3/work/1/s/MyApp.Mobile.sln" (Rebuild target(s)) -- FAILED.
  </code></pre>
  
  <p><strong>UPDATE</strong>
  Got some more information from AppCenter by adding few environment variables to the build and disabling linking for the configuration:</p>
  
  <p>MTOUCH_ENV_OPTIONS '-v -v -v -v'</p>
  
  <p>I wonder how is that different from adding <code>-v -v -v -v</code> to mtouch arguments in the .csproject.
  Anyway, I can now pinpoint <em>which reference exactly is causing trouble</em>.</p>
  
  <pre><code>      Can't find custom attr constructor image: /Users/vsts/agent/2.133.3/work/1/s/co.myapp.ios/obj/iPhone/AppStore/mtouch-cache/64/Build/SomeReference.dll mtoken: 0x0a000004 due to: Could not resolve type with token 01000006 (from typeref, class/assembly ObjCRuntime.BindingImplAttribute, Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065) assembly:Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065 type:ObjCRuntime.BindingImplAttribute member:&lt;none&gt;
        Can't find custom attr constructor image: /Users/vsts/agent/2.133.3/work/1/s/co.myapp.ios/obj/iPhone/AppStore/mtouch-cache/64/Build/SomeReference.dll mtoken: 0x0a000004 due to: Could not resolve type with token 01000006 (from typeref, class/assembly ObjCRuntime.BindingImplAttribute, Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065) assembly:Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065 type:ObjCRuntime.BindingImplAttribute member:&lt;none&gt;
        Can't find custom attr constructor image: /Users/vsts/agent/2.133.3/work/1/s/co.myapp.ios/obj/iPhone/AppStore/mtouch-cache/64/Build/SomeReference.dll mtoken: 0x0a000004 due to: Could not resolve type with token 01000006 (from typeref, class/assembly ObjCRuntime.BindingImplAttribute, Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065) assembly:Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065 type:ObjCRuntime.BindingImplAttribute member:&lt;none&gt;
        Can't find custom attr constructor image: /Users/vsts/agent/2.133.3/work/1/s/co.myapp.ios/obj/iPhone/AppStore/mtouch-cache/64/Build/SomeReference.dll mtoken: 0x0a000004 due to: Could not resolve type with token 01000006 (from typeref, class/assembly ObjCRuntime.BindingImplAttribute, Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065) assembly:Xamarin.iOS, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065 type:ObjCRuntime.BindingImplAttribute member:&lt;none&gt;
  </code></pre>
  
  <p>packages.config:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;packages&gt;
    &lt;package id="Fabric" version="1.4" targetFramework="xamarinios10" /&gt;
    &lt;package id="linqtotwitter" version="4.1.0" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.AppCenter" version="1.6.0" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.AppCenter.Analytics" version="1.6.0" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.AppCenter.Crashes" version="1.6.0" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.Bcl" version="1.1.10" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.Bcl.Build" version="1.0.21" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.Bcl.Compression" version="3.9.85" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.CSharp" version="4.4.0" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.Net.Http" version="2.2.29" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.NETCore.Platforms" version="2.0.1" targetFramework="xamarinios10" /&gt;
    &lt;package id="Microsoft.Win32.Primitives" version="4.3.0" targetFramework="xamarinios10" /&gt;
    &lt;package id="modernhttpclient" version="2.4.2" targetFramework="xamarinios10" /&gt;
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