[build] Target net9.0 (#1279)

Context: 356485e
Context: #1258
Context: dotnet/android#9793

We want to add a call to [Debugger.BreakForUserUnhandledException][0]
-- which was added in .NET 9 -- into `Java.Interop.JniRuntime` as
part of Issues #1258.

In order to do this we need to update `dotnet/java-interop` to build
with .NET 9 instead of .NET 8.

This also contains fixes for new trimming warnings that were surfaced
when targeting .NET 9.

Requires companion changes in `dotnet/android`: dotnet/android#9793

Co-authored-by: Jonathan Peppers <[email protected]>

[0]: https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.debugger.breakforuserunhandledexception

Author: jpobst

Directory.Build.props

@@ -9,7 +9,7 @@
     <ProduceReferenceAssemblyInOutDir>true</ProduceReferenceAssemblyInOutDir>
     <!-- Disables the transitive restore of packages like Microsoft.AspNetCore.App.Ref, Microsoft.WindowsDesktop.App.Ref -->
     <DisableTransitiveFrameworkReferenceDownloads>true</DisableTransitiveFrameworkReferenceDownloads>
-    <DotNetTargetFrameworkVersion>8.0</DotNetTargetFrameworkVersion>
+    <DotNetTargetFrameworkVersion>9.0</DotNetTargetFrameworkVersion>
     <DotNetTargetFramework>net$(DotNetTargetFrameworkVersion)</DotNetTargetFramework>
   </PropertyGroup>
 

build-tools/automation/azure-pipelines.yaml

@@ -19,8 +19,8 @@ pr:
 variables:
   RunningOnCI: true
   Build.Configuration: Release
-  DotNetCoreVersion: 8.0.303
-  DotNetTargetFramework: net8.0
+  DotNetCoreVersion: 9.0.200
+  DotNetTargetFramework: net9.0
   NetCoreTargetFrameworkPathSuffix: -$(DotNetTargetFramework)
   HostedPoolName: Azure Pipelines
   HostedWinImage: windows-2022

src/Java.Interop.Export/Java.Interop/MarshalMemberBuilder.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;
@@ -11,8 +12,12 @@
 
 namespace Java.Interop {
 
+	[RequiresDynamicCode (ExpressionRequiresUnreferencedCode)]
+	[RequiresUnreferencedCode (ExpressionRequiresUnreferencedCode)]
 	public class MarshalMemberBuilder : JniRuntime.JniMarshalMemberBuilder
 	{
+		internal const string ExpressionRequiresUnreferencedCode = "System.Linq.Expression usage may trim away required code.";
+
 		public MarshalMemberBuilder ()
 		{
 		}

src/Java.Interop/Java.Interop/JniRuntime.JniMarshalMemberBuilder.cs

@@ -29,8 +29,13 @@ public  JniMarshalMemberBuilder        MarshalMemberBuilder        {
 
 		internal    bool                       UseMarshalMemberBuilder  => marshalMemberBuilder != null;
 
+		const string NotUsedInAndroid = "This code path is not used in Android projects.";
+
+		// FIXME: https://github.com/dotnet/java-interop/issues/1192
 		[DynamicDependency (DynamicallyAccessedMemberTypes.PublicParameterlessConstructor, "Java.Interop.MarshalMemberBuilder", "Java.Interop.Export")]
+		[UnconditionalSuppressMessage ("Trimming", "IL2026", Justification = NotUsedInAndroid)]
 		[UnconditionalSuppressMessage ("Trimming", "IL2035", Justification = "Java.Interop.Export.dll is not always present.")]
+		[UnconditionalSuppressMessage ("Trimming", "IL3050", Justification = NotUsedInAndroid)]
 		partial void SetMarshalMemberBuilder (CreationOptions options)
 		{
 			if (!options.UseMarshalMemberBuilder) {

src/Java.Interop/Java.Interop/JniRuntime.JniTypeManager.cs

@@ -266,18 +266,16 @@ protected virtual IEnumerable<string> GetSimpleReferences (Type type)
 			static  readonly    Type[]      EmptyTypeArray      = Array.Empty<Type> ();
 			const string NotUsedInAndroid = "This code path is not used in Android projects.";
 
+			// FIXME: https://github.com/dotnet/java-interop/issues/1192
+			[UnconditionalSuppressMessage ("Trimming", "IL3050", Justification = NotUsedInAndroid)]
 			static Type MakeArrayType (Type type) =>
-				// FIXME: https://github.com/dotnet/java-interop/issues/1192
-				#pragma warning disable IL3050
 				type.MakeArrayType ();
-				#pragma warning restore IL3050
 
+			// FIXME: https://github.com/dotnet/java-interop/issues/1192
 			[UnconditionalSuppressMessage ("Trimming", "IL2055", Justification = NotUsedInAndroid)]
+			[UnconditionalSuppressMessage ("Trimming", "IL3050", Justification = NotUsedInAndroid)]
 			static Type MakeGenericType (Type type, Type arrayType) =>
-				// FIXME: https://github.com/dotnet/java-interop/issues/1192
-				#pragma warning disable IL3050
 				type.MakeGenericType (arrayType);
-				#pragma warning restore IL3050
 
 			[UnconditionalSuppressMessage ("Trimming", "IL2073", Justification = "Types returned here should be preserved via other means.")]
 			[return: DynamicallyAccessedMembers (MethodsConstructors)]
@@ -400,16 +398,15 @@ IEnumerable<Type> CreateGetTypesForSimpleReferenceEnumerator (string jniSimpleRe
 				// https://github.com/xamarin/xamarin-android/blob/5472eec991cc075e4b0c09cd98a2331fb93aa0f3/src/Microsoft.Android.Sdk.ILLink/MarkJavaObjects.cs#L176-L186
 				const string makeGenericTypeMessage = "Generic 'Invoker' types are preserved by the MarkJavaObjects trimmer step.";
 
+				// FIXME: https://github.com/dotnet/java-interop/issues/1192
 				[UnconditionalSuppressMessage ("Trimming", "IL2055", Justification = makeGenericTypeMessage)]
+				[UnconditionalSuppressMessage ("Trimming", "IL3050", Justification = makeGenericTypeMessage)]
 				[return: DynamicallyAccessedMembers (Constructors)]
 				static Type MakeGenericType (
 						[DynamicallyAccessedMembers (Constructors)]
 						Type type,
 						Type [] arguments) =>
-					// FIXME: https://github.com/dotnet/java-interop/issues/1192
-					#pragma warning disable IL3050
 					type.MakeGenericType (arguments);
-					#pragma warning restore IL3050
 
 				var signature   = type.GetCustomAttribute<JniTypeSignatureAttribute> ();
 				if (signature == null || signature.InvokerType == null) {

src/Java.Interop/Java.Interop/JniRuntime.JniValueManager.cs

@@ -675,12 +675,11 @@ static JniValueMarshaler GetObjectArrayMarshaler (Type elementType)
 			{
 				const string makeGenericMethodMessage = "This code path is not used in Android projects.";
 
+				// FIXME: https://github.com/dotnet/java-interop/issues/1192
 				[UnconditionalSuppressMessage ("Trimming", "IL2060", Justification = makeGenericMethodMessage)]
+				[UnconditionalSuppressMessage ("Trimming", "IL3050", Justification = makeGenericMethodMessage)]
 				static MethodInfo MakeGenericMethod (MethodInfo method, Type type) =>
-					// FIXME: https://github.com/dotnet/java-interop/issues/1192
-					#pragma warning disable IL3050
 					method.MakeGenericMethod (type);
-					#pragma warning restore IL3050
 
 				Func<JniValueMarshaler> indirect = GetObjectArrayMarshalerHelper<object>;
 				var reifiedMethodInfo = MakeGenericMethod (

src/Java.Interop/Java.Interop/JniRuntime.cs

@@ -446,8 +446,7 @@ public virtual void OnUserUnhandledException (ref JniTransition transition, Exce
 		{
 			transition.SetPendingException (e);
 
-			// TODO: Enable when we move to 'net9.0'
-			//Debugger.BreakForUserUnhandledException (e);
+			Debugger.BreakForUserUnhandledException (e);
 		}
 
 		public virtual void RaisePendingException (Exception pendingException)

src/Java.Interop/Java.Interop/JniValueMarshaler.cs

@@ -177,6 +177,7 @@ Expression CreateSelf (JniValueMarshalerContext context, ParameterExpression sou
 			return self;
 		}
 
+		[UnconditionalSuppressMessage ("Trimming", "IL2073", Justification = ExpressionRequiresUnreferencedCode)]
 		[return: DynamicallyAccessedMembers (DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)]
 		Type _GetType () => GetType ();
 

src/Java.Runtime.Environment/Java.Interop/JreTypeManager.cs

@@ -4,6 +4,7 @@
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -17,7 +18,13 @@ namespace Java.Interop {
 
 	public class JreTypeManager : JniRuntime.JniTypeManager {
 
-		public override void RegisterNativeMembers (JniType nativeClass, Type type, ReadOnlySpan<char> methods)
+		const string NotUsedInAndroid = "This code path is not used in Android projects.";
+
+		public override void RegisterNativeMembers (
+				JniType nativeClass,
+				[DynamicallyAccessedMembers (MethodsAndPrivateNested)]
+				Type type,
+				ReadOnlySpan<char> methods)
 		{
 			if (base.TryRegisterNativeMembers (nativeClass, type, methods)) {
 				return;
@@ -63,6 +70,10 @@ public override void RegisterNativeMembers (JniType nativeClass, Type type, Read
 			nativeClass.RegisterNativeMethods (registrations.ToArray ());
 		}
 
+		// FIXME: https://github.com/dotnet/java-interop/issues/1192
+		[UnconditionalSuppressMessage ("Trimming", "IL2062", Justification = NotUsedInAndroid)]
+		[UnconditionalSuppressMessage ("Trimming", "IL2070", Justification = NotUsedInAndroid)]
+		[UnconditionalSuppressMessage ("Trimming", "IL2078", Justification = NotUsedInAndroid)]
 		static void AddInterfaceMethods (JniMethodMap toRegister, Type type)
 		{
 			foreach (var iface in type.GetInterfaces ()) {
@@ -86,7 +97,9 @@ static void AddJniMethod (JniMethodMap toRegister, MethodInfo declaringMethod, M
 			toRegister [("n_" + signature.MemberName, signature.MemberSignature)]   = targetMethod ?? declaringMethod;
 		}
 
-		static void AddClassMethods (JniMethodMap toRegister, Type type)
+		// FIXME: https://github.com/dotnet/java-interop/issues/1192
+		[UnconditionalSuppressMessage ("Trimming", "IL2070", Justification = NotUsedInAndroid)]
+		static void AddClassMethods (JniMethodMap toRegister, [DynamicallyAccessedMembers (Methods)] Type type)
 		{
 			const BindingFlags Flags = BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance;
 			foreach (var method in type.GetMethods (Flags)) {

src/Java.Runtime.Environment/Java.Interop/ManagedValueManager.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -231,12 +232,17 @@ void ActivateViaReflection (JniObjectReference reference, ConstructorInfo cinfo,
 		{
 			var declType  = cinfo.DeclaringType ?? throw new NotSupportedException ("Do not know the type to create!");
 
-#pragma warning disable IL2072
-			var self      = (IJavaPeerable) System.Runtime.CompilerServices.RuntimeHelpers.GetUninitializedObject (declType);
-#pragma warning restore IL2072
+			var self      = GetUninitializedObject (declType);
 			self.SetPeerReference (reference);
 
 			cinfo.Invoke (self, argumentValues);
+
+			// FIXME: https://github.com/dotnet/java-interop/issues/1192
+			const string getUninitializedObject = "This code path is not used in Android projects.";
+			[UnconditionalSuppressMessage ("Trimming", "IL2067", Justification = getUninitializedObject)]
+			[UnconditionalSuppressMessage ("Trimming", "IL2072", Justification = getUninitializedObject)]
+			static IJavaPeerable GetUninitializedObject (Type type) =>
+				(IJavaPeerable) System.Runtime.CompilerServices.RuntimeHelpers.GetUninitializedObject (type);
 		}
 
 		public override List<JniSurfacedPeerInfo> GetSurfacedPeers ()