[TrimmableTypeMap] Remove ForceUnconditionalEntries workaround

src/Microsoft.Android.Sdk.TrimmableTypeMap/Generator/ModelBuilder.cs

@@ -16,13 +16,6 @@ static class ModelBuilder
 {
 	const string ProxyTypeSuffix = "_Proxy";
 
-	// Workaround for https://github.com/dotnet/runtime/issues/127004
-	// When true, all TypeMap entries are emitted as 2-arg (unconditional) to avoid the
-	// trimmer bug that strips TypeMapAssociation attributes when a TypeMap attribute
-	// references the same type. Set to false once the runtime bug is fixed to re-enable
-	// 3-arg conditional entries that allow unused framework bindings to be trimmed away.
-	const bool ForceUnconditionalEntries = true;
-
 	static readonly HashSet<string> EssentialRuntimeTypes = new (StringComparer.Ordinal) {
 		"java/lang/Object",
 		"java/lang/Class",
@@ -189,13 +182,7 @@ static void EmitPeers (TypeMapAssemblyData model, string jniName,
 		}
 
 		// Base JNI name entry → alias holder (self-referencing trim target, kept alive by associations)
-		// When ForceUnconditionalEntries is true we MUST emit this as 2-arg (unconditional) just
-		// like BuildEntry does: dotnet/runtime#127004 strips the TypeMapAssociation that keeps the
-		// holder alive when a TypeMap entry references the same type, leaving the dictionary key
-		// missing at runtime and breaking hierarchy lookups for essential types like
-		// java/lang/String and java/lang/Object.
-		bool aliasBaseUnconditional = ForceUnconditionalEntries
-			|| EssentialRuntimeTypes.Contains (jniName)
+		bool aliasBaseUnconditional = EssentialRuntimeTypes.Contains (jniName)
 			|| peersForName.Any (IsUnconditionalEntry);
 		model.Entries.Add (new TypeMapAttributeData {
 			JniName = jniName,
@@ -406,9 +393,7 @@ static TypeMapAttributeData BuildEntry (JavaPeerInfo peer, JavaPeerProxyData? pr
 			proxyRef = AssemblyQualify (peer.ManagedTypeName, peer.AssemblyName);
 		}
 
-		// When ForceUnconditionalEntries is true, always emit 2-arg (unconditional) TypeMap
-		// attributes to work around https://github.com/dotnet/runtime/issues/127004.
-		bool isUnconditional = ForceUnconditionalEntries || IsUnconditionalEntry (peer);
+		bool isUnconditional = IsUnconditionalEntry (peer);
 		string? targetRef = null;
 		if (!isUnconditional) {
 			targetRef = AssemblyQualify (peer.ManagedTypeName, peer.AssemblyName);

src/Mono.Android/Xamarin.Android.Net/ServerCertificateCustomValidator.cs

@@ -2,6 +2,7 @@
 using System.Diagnostics.CodeAnalysis;
 using System.Net.Http;
 using System.Net.Security;
+using System.Runtime.CompilerServices;
 using System.Security.Cryptography.X509Certificates;
 
 using Android.OS;
@@ -170,34 +171,34 @@ private sealed class AlwaysAcceptingHostnameVerifier : Java.Lang.Object, IHostna
 			public bool Verify (string? hostname, ISSLSession? session) => true;
 		}
 
-		[DynamicDependency(nameof(IX509TrustManager.CheckServerTrusted), typeof(IX509TrustManagerInvoker))]
-		[DynamicDependency(nameof(IX509TrustManager.CheckServerTrusted), typeof(X509ExtendedTrustManagerInvoker))]
 		private static IX509TrustManager FindX509TrustManager(ITrustManager[] trustManagers, out int index)
 		{
+			index = -1;
+
 			for (int i = 0; i < trustManagers.Length; i++) {
 				var trustManager = trustManagers [i];
 				if (trustManager is IX509TrustManager x509TrustManager) {
 					index = i;
 					return x509TrustManager;
 				}
+			}
 
-				// On API 21-23, the default Java trust manager is TrustManagerImpl from Conscrypt. The class implements X509TrustManager
-				// but the .NET pattern matching will fail in this case and we need to cast it explicitly.
-				int apiLevel = (int)Build.VERSION.SdkInt;
-				if (apiLevel <= 23) {
-					if (IsTrustManagerImpl (trustManager)) {
-						index = i;
-						return trustManager.JavaCast<IX509TrustManager> ();
-					}
-				}
+			if (trustManagers.Length > 10_000) {
+				HackToPreserveInvokers(trustManagers);
 			}
 
 			throw new InvalidOperationException($"Could not find {nameof(IX509TrustManager)} in {nameof(ITrustManager)} array.");
+		}
 
-			static bool IsTrustManagerImpl (ITrustManager trustManager)
-			{
-				var javaClassName = JNIEnv.GetClassNameFromInstance (trustManager.Handle);
-				return javaClassName.Equals ("com/android/org/conscrypt/TrustManagerImpl", StringComparison.Ordinal);
+		[MethodImpl (MethodImplOptions.NoInlining)]
+		static void HackToPreserveInvokers (ITrustManager[] trustManagers)
+		{
+			// HACK - make IX509TrustManagerInvoker visible to the linker so that it doesn't get trimmed out.
+			// These branches are unreachable, but the linker doesn't know that.
+			if (trustManagers.Length > 1_000_000) {
+				_ = new IX509TrustManagerInvoker (IntPtr.Zero, JniHandleOwnership.DoNotTransfer);
+			} else if (trustManagers.Length > 2_000_000) {
+				_ = new X509ExtendedTrustManagerInvoker (IntPtr.Zero, JniHandleOwnership.DoNotTransfer);
 			}
 		}
 

src/Mono.Android/map.csv

@@ -478,9 +478,9 @@ E,36,android/app/appfunctions/AppFunctionException.ERROR_ENTERPRISE_POLICY_DISAL
 E,36,android/app/appfunctions/AppFunctionException.ERROR_FUNCTION_NOT_FOUND,1003,Android.App.AppFunctions.AppFunctionError,FunctionNotFound,remove,
 E,36,android/app/appfunctions/AppFunctionException.ERROR_INVALID_ARGUMENT,1001,Android.App.AppFunctions.AppFunctionError,InvalidArgument,remove,
 E,36,android/app/appfunctions/AppFunctionException.ERROR_SYSTEM_ERROR,2000,Android.App.AppFunctions.AppFunctionError,SystemError,remove,
-E,36,android/app/appfunctions/AppFunctionManager.APP_FUNCTION_STATE_DEFAULT,0,Android.App.AppFunctions.AppFunctionState,Default,remove,
-E,36,android/app/appfunctions/AppFunctionManager.APP_FUNCTION_STATE_DISABLED,2,Android.App.AppFunctions.AppFunctionState,Disabled,remove,
-E,36,android/app/appfunctions/AppFunctionManager.APP_FUNCTION_STATE_ENABLED,1,Android.App.AppFunctions.AppFunctionState,Enabled,remove,
+E,36,android/app/appfunctions/AppFunctionManager.APP_FUNCTION_STATE_DEFAULT,0,Android.App.AppFunctions.AppFunctionEnabledState,Default,remove,
+E,36,android/app/appfunctions/AppFunctionManager.APP_FUNCTION_STATE_DISABLED,2,Android.App.AppFunctions.AppFunctionEnabledState,Disabled,remove,
+E,36,android/app/appfunctions/AppFunctionManager.APP_FUNCTION_STATE_ENABLED,1,Android.App.AppFunctions.AppFunctionEnabledState,Enabled,remove,
 E,37,android/app/appfunctions/AppFunctionMetadata.SCOPE_ACTIVITY,1,Android.App.AppFunctions.AppFunctionMetadataScope,Activity,remove,
 E,37,android/app/appfunctions/AppFunctionMetadata.SCOPE_GLOBAL,0,Android.App.AppFunctions.AppFunctionMetadataScope,Global,remove,
 E,37,android/app/AppInteractionAttribution.INTERACTION_TYPE_OTHER,0,Android.App.AppInteractionAttributionInteractionType,Other,remove,

src/Mono.Android/methodmap.csv

@@ -4100,7 +4100,7 @@
 36,android.app.appfunctions,AppFunctionException,getErrorCategory,return,Android.App.AppFunctions.AppFunctionErrorCategory
 36,android.app.appfunctions,AppFunctionException,getErrorCode,return,Android.App.AppFunctions.AppFunctionError
 36,android.app.appfunctions,AppFunctionException,writeToParcel,flags,Android.OS.ParcelableWriteFlags
-36,android.app.appfunctions,AppFunctionManager,setAppFunctionEnabled,newEnabledState,Android.App.AppFunctions.AppFunctionState
+36,android.app.appfunctions,AppFunctionManager,setAppFunctionEnabled,newEnabledState,Android.App.AppFunctions.AppFunctionEnabledState
 36,android.app.appfunctions,ExecuteAppFunctionRequest,writeToParcel,flags,Android.OS.ParcelableWriteFlags
 36,android.app.appfunctions,ExecuteAppFunctionResponse,writeToParcel,flags,Android.OS.ParcelableWriteFlags
 36,android.app,ApplicationStartInfo,getStartComponent,return,Android.App.ApplicationStartInfoStartComponent

tests/Microsoft.Android.Sdk.TrimmableTypeMap.Tests/Generator/TypeMapModelBuilderTests.cs

@@ -172,14 +172,12 @@ public void Build_UserAcwType_IsUnconditional ()
 		public void Build_McwBinding_IsTrimmable ()
 		{
 			// MCW binding types (DoNotGenerateAcw=true) are trimmable unless essential.
-			// When ForceUnconditionalEntries is enabled (workaround for dotnet/runtime#127004),
-			// all entries become unconditional.
 			var peer = MakeMcwPeer ("android/app/Activity", "Android.App.Activity", "Mono.Android") with { DoNotGenerateAcw = true };
 			var model = BuildModel (new [] { peer });
 
 			Assert.Single (model.Entries);
-			Assert.True (model.Entries [0].IsUnconditional);
-			Assert.Null (model.Entries [0].TargetTypeReference);
+			Assert.False (model.Entries [0].IsUnconditional);
+			Assert.Equal ("Android.App.Activity, Mono.Android", model.Entries [0].TargetTypeReference);
 		}
 
 		[Fact]
@@ -248,8 +246,8 @@ public void Build_PeerWithActivation_CreatesNamedProxy (string jniName, string m
 		[Fact]
 		public void Build_SinglePeer_HasAssociation ()
 		{
-			// When ForceUnconditionalEntries is enabled, single peers emit associations
-			// so the runtime proxy type map is populated.
+			// Single peers with generated proxies emit associations so the runtime proxy
+			// type map is populated.
 			var peer = MakePeerWithActivation ("my/app/MainActivity", "MyApp.MainActivity", "App");
 			var model = BuildModel (new [] { peer }, "MyTypeMap");
 
@@ -338,8 +336,8 @@ public void Fixture_McwBinding_IsTrimmable (string javaName)
 			var peer = FindFixtureByJavaName (javaName);
 			Assert.True (peer.DoNotGenerateAcw);
 			var model = BuildModel (new [] { peer });
-			// ForceUnconditionalEntries workaround makes all entries unconditional
-			Assert.True (model.Entries [0].IsUnconditional);
+			Assert.False (model.Entries [0].IsUnconditional);
+			Assert.NotNull (model.Entries [0].TargetTypeReference);
 		}
 	}
 
@@ -776,7 +774,6 @@ public class PeBlobValidation
 		[Fact]
 		public void FullPipeline_Mixed2ArgAnd3Arg_BothSurviveRoundTrip ()
 		{
-			// With ForceUnconditionalEntries, both are emitted as 2-arg unconditional
 			var objectPeer = FindFixtureByJavaName ("java/lang/Object");
 			var activityPeer = FindFixtureByJavaName ("android/app/Activity");
 
@@ -793,7 +790,7 @@ public void FullPipeline_Mixed2ArgAnd3Arg_BothSurviveRoundTrip ()
 
 				var activityEntry = attrs.FirstOrDefault (a => a.jniName == "android/app/Activity");
 				Assert.NotNull (activityEntry.jniName);
-				Assert.Null (activityEntry.targetRef); // unconditional due to ForceUnconditionalEntries
+				Assert.Equal ("Android.App.Activity, TestFixtures", activityEntry.targetRef);
 			});
 		}
 
@@ -818,22 +815,20 @@ public void FullPipeline_UnconditionalType_Emits2ArgAttribute (string javaName,
 		}
 
 		[Fact]
-		public void FullPipeline_McwBinding_Emits2ArgAttribute_WithWorkaround ()
+		public void FullPipeline_McwBinding_Emits3ArgAttribute ()
 		{
-			// With ForceUnconditionalEntries workaround for dotnet/runtime#127004,
-			// MCW bindings are emitted as 2-arg unconditional.
 			var peer = FindFixtureByJavaName ("android/app/Activity");
-			var model = BuildModel (new [] { peer }, "Blob2ArgWorkaround");
+			var model = BuildModel (new [] { peer }, "Blob3ArgConditional");
 			Assert.Single (model.Entries);
-			Assert.True (model.Entries [0].IsUnconditional);
+			Assert.False (model.Entries [0].IsUnconditional);
 
-			EmitAndVerify (model, "Blob2ArgWorkaround", (pe, reader) => {
+			EmitAndVerify (model, "Blob3ArgConditional", (pe, reader) => {
 				var (jniName, proxyRef, targetRef) = ReadFirstTypeMapAttributeBlob (reader);
 
 				Assert.Equal ("android/app/Activity", jniName);
 				Assert.NotNull (proxyRef);
 				Assert.Contains ("Android_App_Activity_Proxy", proxyRef!);
-				Assert.Null (targetRef); // unconditional due to ForceUnconditionalEntries
+				Assert.Equal ("Android.App.Activity, TestFixtures", targetRef);
 			});
 		}
 	}