ILLink: Avoid warning for RUC field rooted as part of a root assembly (…

…#108498)

Similar to #81864, fields
in a RUC class are producing trim analysis warnings in the OOB
trim step (the mentioned issue was specific to library mode, but
it's also a problem for the normal root assembly mode).

This extends the fix from
#84620 to avoid producing
warnings for fields that are marked just because an assembly was
rooted. Arguably rooting an assembly _should_ warn about rooted
RUC members, but that's not the case today for RUC methods, so
this makes the behavior consistent for fields.

---------

Co-authored-by: Jackson Schuster <[email protected]>

src/tools/illink/src/linker/Linker.Steps/MarkStep.cs

@@ -1728,6 +1728,7 @@ void ProcessAnalysisAnnotationsForField (FieldDefinition field, DependencyKind d
 			case DependencyKind.AlreadyMarked:
 			case DependencyKind.TypePreserve:
 			case DependencyKind.PreservedMethod:
+			case DependencyKind.MemberOfType:
 				return;
 
 			case DependencyKind.DynamicallyAccessedMemberOnType:

src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresInRootAllAssembly.cs

@@ -0,0 +1,59 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System;
+using System.Diagnostics.CodeAnalysis;
+using Mono.Linker.Tests.Cases.Expectations.Assertions;
+using Mono.Linker.Tests.Cases.Expectations.Metadata;
+
+namespace Mono.Linker.Tests.Cases.RequiresCapability
+{
+	[SetupLinkerArgument ("-a", "test.exe", "all")]
+
+	[SkipKeptItemsValidation]
+	[ExpectedNoWarnings]
+	public class RequiresInRootAllAssembly
+	{
+		public static void Main ()
+		{
+		}
+
+		[RequiresDynamicCode ("--MethodWhichRequires--")]
+		public static void MethodWhichRequires () { }
+
+		[RequiresDynamicCode ("--InstanceMethodWhichRequires--")]
+		public void InstanceMethodWhichRequires () { }
+
+		public sealed class ClassWithDAMAnnotatedMembers
+		{
+			public static void Method ([DynamicallyAccessedMembers (DynamicallyAccessedMemberTypes.PublicMethods)] Type type) { }
+
+			[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)]
+			public static Type Field;
+		}
+
+		[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)]
+		public sealed class ClassWithDAMAnnotation
+		{
+			public void Method () { }
+		}
+
+		[RequiresUnreferencedCode ("--ClassWithRequires--")]
+		public sealed class ClassWithRequires
+		{
+			public static int Field;
+
+			internal static int InternalField;
+
+			private static int PrivateField;
+
+			public static void Method () { }
+
+			public void InstanceMethod () { }
+
+			public static int Property { get; set; }
+
+			public static event EventHandler PropertyChanged;
+		}
+	}
+}