Move FixLegacyResourceDesignerStep to post-trim pipeline

src/Microsoft.Android.Sdk.ILLink/Microsoft.Android.Sdk.ILLink.csproj

@@ -16,8 +16,6 @@
     <Compile Include="..\Xamarin.Android.Build.Tasks\Linker\External\Linker\BaseMarkHandler.cs" Link="External\BaseMarkHandler.cs" />
     <Compile Include="..\Xamarin.Android.Build.Tasks\Linker\MonoDroid.Tuner\AndroidLinkConfiguration.cs" Link="MonoDroid.Tuner\AndroidLinkConfiguration.cs" />
     <Compile Include="..\Xamarin.Android.Build.Tasks\Linker\MonoDroid.Tuner\Extensions.cs" Link="MonoDroid.Tuner\Extensions.cs" />
-    <Compile Include="..\Xamarin.Android.Build.Tasks\Linker\MonoDroid.Tuner\FixLegacyResourceDesignerStep.cs" Link="MonoDroid.Tuner\FixLegacyResourceDesignerStep.cs" />
-    <Compile Include="..\Xamarin.Android.Build.Tasks\Linker\MonoDroid.Tuner\LinkDesignerBase.cs" Link="MonoDroid.Tuner\LinkDesignerBase.cs" />
 
     <!--Other .NET for Android / Java.Interop files-->
     <Compile Include="..\..\external\Java.Interop\src\Java.Interop.Tools.Cecil\Java.Interop.Tools.Cecil\CustomAttributeProviderRocks.cs" Link="Java.Interop\CustomAttributeProviderRocks.cs" />

src/Xamarin.Android.Build.Tasks/Linker/External/Linker.Steps/BaseStep.cs

@@ -89,11 +89,7 @@ public virtual void LogMessage (string message)
 
 		public virtual void LogError (int code, string message)
 		{
-#if ILLINK
-			Context.LogMessage (MessageContainer.CreateCustomErrorMessage (message, code, origin: new MessageOrigin ()));
-#else   // !ILLINK
 			Context.LogError ($"XA{code}", message);
-#endif  // !ILLINK
 		}
 	}
 }

src/Xamarin.Android.Build.Tasks/Linker/MonoDroid.Tuner/FixLegacyResourceDesignerStep.cs

@@ -14,18 +14,11 @@
 using Mono.Linker.Steps;
 
 using Mono.Tuner;
-#if ILLINK
-using Resources = Microsoft.Android.Sdk.ILLink.Properties.Resources;
-#else   // !ILLINK
 using Resources = Xamarin.Android.Tasks.Properties.Resources;
-#endif  // ILLINK
 
 namespace MonoDroid.Tuner
 {
-	public class FixLegacyResourceDesignerStep : LinkDesignerBase
-#if !ILLINK
-		, Xamarin.Android.Tasks.IAssemblyModifierPipelineStep
-#endif  // !ILLINK
+	public class FixLegacyResourceDesignerStep : LinkDesignerBase, Xamarin.Android.Tasks.IAssemblyModifierPipelineStep
 	{
 		internal const string DesignerAssemblyName = "_Microsoft.Android.Resource.Designer";
 		internal const string DesignerAssemblyNamespace = "_Microsoft.Android.Resource.Designer";
@@ -36,14 +29,6 @@ public class FixLegacyResourceDesignerStep : LinkDesignerBase
 		Dictionary<string, MethodDefinition> lookup;
 		Dictionary<string, MethodDefinition> lookupCaseInsensitive;
 
-		protected override void EndProcess ()
-		{
-			if (designerAssembly != null) {
-				LogMessage ($"  Setting Action on {designerAssembly.Name} to Link.");
-				Annotations.SetAction (designerAssembly, AssemblyAction.Link);
-			}
-		}
-
 		protected override void LoadDesigner ()
 		{
 			if (designerLoaded)
@@ -72,7 +57,6 @@ protected override void LoadDesigner ()
 			}
 		}
 
-#if !ILLINK
 		public void ProcessAssembly (AssemblyDefinition assembly, Xamarin.Android.Tasks.StepContext context)
 		{
 			// Only run this step on non-main user Android assemblies
@@ -81,7 +65,6 @@ public void ProcessAssembly (AssemblyDefinition assembly, Xamarin.Android.Tasks.
 
 			context.IsAssemblyModified |= ProcessAssemblyDesigner (assembly);
 		}
-#endif  // !ILLINK
 
 		internal override bool ProcessAssemblyDesigner (AssemblyDefinition assembly)
 		{

src/Xamarin.Android.Build.Tasks/Linker/MonoDroid.Tuner/LinkDesignerBase.cs

@@ -4,43 +4,27 @@
 using Mono.Linker;
 using Mono.Linker.Steps;
 using System;
-using System.Linq;
 using Xamarin.Android.Tasks;
 using System.Collections.Generic;
 using System.Globalization;
 using Mono.Cecil.Cil;
 using System.Text.RegularExpressions;
 using Mono.Collections.Generic;
-#if ILLINK
-using Microsoft.Android.Sdk.ILLink;
-#endif
 
 
 namespace MonoDroid.Tuner  {
 	public abstract class LinkDesignerBase : BaseStep
 	{
 		protected IMetadataResolver Cache => Context;
 
-		public
-#if !ILLINK
-		override
-#endif
-		void LogMessage (string message)
+		public override void LogMessage (string message)
 		{
 			Context.LogMessage (message);
 		}
 
-		public
-#if !ILLINK
-		override
-#endif
-		void LogError (int code, string error)
+		public override void LogError (int code, string error)
 		{
-#if ILLINK
-			Context.LogMessage (MessageContainer.CreateCustomErrorMessage (error, code, origin: new MessageOrigin ()));
-#else   // !ILLINK
 			Context.LogError ($"XA{code}", error);
-#endif  // !ILLINK
 		}
 
 		public virtual AssemblyDefinition Resolve (AssemblyNameReference name)

src/Xamarin.Android.Build.Tasks/MSBuild/Xamarin/Android/Xamarin.Android.Resource.Designer.targets

@@ -226,18 +226,37 @@ Copyright (C) 2016 Xamarin. All rights reserved.
     In additon we MUST set the `PostprocessAssembly` metadata to `true` so that the file
     is processed by the ILLink step. If we do not do this then the reference to
     `netstandard.dll` is not replaced with `System.Private.CoreLib` and the app crashes.
+
+    We use a TrimmerRootDescriptor (not TrimmerRootAssembly) to prevent ILLink from
+    trimming the designer's resource properties. FixLegacyResourceDesignerStep runs
+    after ILLink and needs all properties present when rewriting library assemblies.
+    A descriptor (-x) preserves types without making the assembly an entry point,
+    which avoids pulling netstandard.dll into the output.
 -->
 <Target Name="_AddResourceDesignerToPublishFiles"
     Condition=" '$(AndroidUseDesignerAssembly)' == 'True' "
     AfterTargets="ComputeResolvedFilesToPublishList"
     DependsOnTargets="_SetupDesignerProperties">
+  <PropertyGroup>
+    <_DesignerLinkerDescriptor>$(IntermediateOutputPath)_Microsoft.Android.Resource.Designer.xml</_DesignerLinkerDescriptor>
+  </PropertyGroup>
+  <WriteLinesToFile
+      File="$(_DesignerLinkerDescriptor)"
+      Overwrite="true"
+      Lines="&lt;linker&gt;&lt;assembly fullname=&quot;$(_DesignerAssemblyName)&quot;&gt;&lt;type fullname=&quot;*&quot; preserve=&quot;all&quot; /&gt;&lt;/assembly&gt;&lt;/linker&gt;"
+  />
   <ItemGroup>
     <ResolvedFileToPublish Include="$(_GenerateResourceDesignerAssemblyOutput)">
       <RelativePath>$(_DesignerAssemblyName).dll</RelativePath>
       <CopyToPublishDirectory>PreserveNewest</CopyToPublishDirectory>
       <PostprocessAssembly>true</PostprocessAssembly>
       <IsTrimmable>true</IsTrimmable>
     </ResolvedFileToPublish>
+    <!-- Preserve all designer types/members via descriptor so ILLink keeps resource
+         properties. Using a descriptor (not TrimmerRootAssembly) avoids making the
+         assembly an entry point, which would pull netstandard.dll into the output. -->
+    <TrimmerRootDescriptor Include="$(_DesignerLinkerDescriptor)" />
+    <FileWrites Include="$(_DesignerLinkerDescriptor)" />
   </ItemGroup>
 </Target>
 

src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.TypeMap.LlvmIr.targets

@@ -160,7 +160,7 @@
   <Target Name="_PrepareLinking"
       Condition=" '$(PublishTrimmed)' == 'true' "
       AfterTargets="ComputeResolvedFilesToPublishList"
-      DependsOnTargets="GetReferenceAssemblyPaths;_CreatePropertiesCache">
+      DependsOnTargets="GetReferenceAssemblyPaths;_CreatePropertiesCache;_AddResourceDesignerToPublishFiles">
     <PropertyGroup>
       <TrimmerRemoveSymbols Condition=" '$(AndroidIncludeDebugSymbols)' != 'true' ">true</TrimmerRemoveSymbols>
       <_ExtraTrimmerArgs Condition=" '$(_EnableSerializationDiscovery)' != 'false' ">--enable-serialization-discovery $(_ExtraTrimmerArgs)</_ExtraTrimmerArgs>
@@ -197,12 +197,6 @@
       <_TrimmerCustomSteps Include="$(_AndroidLinkerCustomStepAssembly)" Type="Microsoft.Android.Sdk.ILLink.PreserveJavaInterfaces" />
       <!-- Custom steps that run after MarkStep -->
       <!-- Custom steps that run after CleanStep -->
-      <_TrimmerCustomSteps
-          Condition=" '$(AndroidUseDesignerAssembly)' == 'true' "
-          Include="$(_AndroidLinkerCustomStepAssembly)"
-          BeforeStep="MarkStep"
-          Type="MonoDroid.Tuner.FixLegacyResourceDesignerStep"
-      />
       <_TrimmerCustomSteps
           Condition=" '$(_AndroidTypeMapImplementation)' == 'managed' "
           Include="$(_AndroidLinkerCustomStepAssembly)"
@@ -247,7 +241,8 @@
         Assemblies="@(_PostTrimmingAssembly)"
         AddKeepAlives="$(AndroidAddKeepAlives)"
         AndroidLinkResources="$(AndroidLinkResources)"
-        Deterministic="$(Deterministic)" />
+        Deterministic="$(Deterministic)"
+        UseDesignerAssembly="$(AndroidUseDesignerAssembly)" />
   </Target>
 
   <!-- Inject _TypeMapKind into the property cache -->

src/Xamarin.Android.Build.Tasks/Tasks/PostTrimmingPipeline.cs

@@ -6,6 +6,7 @@
 using Microsoft.Android.Build.Tasks;
 using Microsoft.Build.Framework;
 using Mono.Cecil;
+using Mono.Linker;
 using MonoDroid.Tuner;
 
 namespace Xamarin.Android.Tasks;
@@ -34,6 +35,8 @@ public class PostTrimmingPipeline : AndroidTask
 
 	public bool Deterministic { get; set; }
 
+	public bool UseDesignerAssembly { get; set; }
+
 	public override bool RunTask ()
 	{
 		using var resolver = new DirectoryAssemblyResolver (
@@ -100,6 +103,15 @@ public override bool RunTask ()
 				},
 				(msg) => Log.LogDebugMessage (msg)));
 		}
+		if (UseDesignerAssembly) {
+			// Create an MSBuildLinkContext so FixLegacyResourceDesignerStep can resolve assemblies
+			// and log messages. The resolver is owned by the outer 'using' block, so we intentionally
+			// do not dispose this context (LinkContext.Dispose would double-dispose the resolver).
+			var linkContext = new MSBuildLinkContext (resolver, Log);
+			var fixLegacyStep = new FixLegacyResourceDesignerStep ();
+			fixLegacyStep.Initialize (linkContext);
+			steps.Add (new PostTrimmingFixLegacyResourceDesignerStep (fixLegacyStep));
+		}
 
 		foreach (var (item, assembly) in loadedAssemblies) {
 			var context = new StepContext (item, item);
@@ -118,3 +130,24 @@ public override bool RunTask ()
 		return !Log.HasLoggedErrors;
 	}
 }
+
+/// <summary>
+/// Thin wrapper around <see cref="FixLegacyResourceDesignerStep"/> for the post-trimming pipeline.
+/// Calls <see cref="FixLegacyResourceDesignerStep.ProcessAssemblyDesigner"/> directly, matching the
+/// behavior of the former ILLink path which processed all assemblies without StepContext flag filtering.
+/// Assemblies without a resource designer are skipped internally by ProcessAssemblyDesigner.
+/// </summary>
+class PostTrimmingFixLegacyResourceDesignerStep : IAssemblyModifierPipelineStep
+{
+	readonly FixLegacyResourceDesignerStep _inner;
+
+	public PostTrimmingFixLegacyResourceDesignerStep (FixLegacyResourceDesignerStep inner)
+	{
+		_inner = inner;
+	}
+
+	public void ProcessAssembly (AssemblyDefinition assembly, StepContext context)
+	{
+		context.IsAssemblyModified |= _inner.ProcessAssemblyDesigner (assembly);
+	}
+}

src/Xamarin.Android.Build.Tasks/Xamarin.Android.Build.Tasks.csproj

@@ -45,7 +45,7 @@
     <Compile Include="..\..\bin\Build$(Configuration)\XABuildConfig.cs" />
 
     <!-- Include only the linker sources required for the build tasks (LinkAssembliesNoShrink and PostTrimmingPipeline) -->
-    <!-- These include: AddKeepAlivesStep, AddKeepAlivesHelper, CheckForObsoletePreserveAttributeStep, StripEmbeddedLibrariesStep, PostTrimmingAddKeepAlivesStep, FixAbstractMethodsStep, FixLegacyResourceDesignerStep -->
+    <!-- These include: AddKeepAlivesStep, AddKeepAlivesHelper, CheckForObsoletePreserveAttributeStep, StripEmbeddedLibrariesStep, PostTrimmingAddKeepAlivesStep, FixAbstractMethodsStep, FixLegacyResourceDesignerStep, LinkDesignerBase -->
     <Compile Remove="Linker\**" />
     <Compile Include="Linker\MonoDroid.Tuner\FindTypeMapObjectsStep.cs" />
     <Compile Include="Linker\MonoDroid.Tuner\FindJavaObjectsStep.cs" />

tests/MSBuildDeviceIntegration/Tests/InstallAndRunTests.cs

@@ -1423,7 +1423,7 @@ private void OnPaintSurface(object sender, SKPaintSurfaceEventArgs e)
 				// TODO: fix for NativeAOT
 				if (!addResource && runtime != AndroidRuntime.NativeAOT) {
 					Assert.IsFalse (b.Build (app, doNotCleanupOnUpdate: true), $"Build of {app.ProjectName} should have failed.");
-					Assert.IsTrue (b.LastBuildOutput.ContainsText (isRelease ? "IL8000" : "XA8000"));
+					Assert.IsTrue (b.LastBuildOutput.ContainsText ("XA8000"));
 					Assert.IsTrue (b.LastBuildOutput.ContainsText ("@styleable/SKCanvasView"), "Expected '@styleable/SKCanvasView' in build output.");
 					Assert.IsTrue (b.LastBuildOutput.ContainsText ("@styleable/SKCanvasView_ignorePixelScaling"), "Expected '@styleable/SKCanvasView_ignorePixelScaling' in build output.");
 					return;