From b6609f25fad5abb834550256eb46f23348d90e29 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 13 Jul 2026 18:53:07 +0000
Subject: [PATCH 1/2] Initial plan


From 860048e3fa9c978bfa8662a8b585fb55e378d181 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 13 Jul 2026 19:44:54 +0000
Subject: [PATCH 2/2] Add ILLink unused annotation regression coverage

Co-authored-by: jtschuster <36744439+jtschuster@users.noreply.github.com>
---
 .../UnusedVirtualMethodAnnotations.cs         | 84 +++++++++++++++++++
 1 file changed, 84 insertions(+)
 create mode 100644 src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/UnusedVirtualMethodAnnotations.cs

diff --git a/src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/UnusedVirtualMethodAnnotations.cs b/src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/UnusedVirtualMethodAnnotations.cs
new file mode 100644
index 00000000000000..9137a74c34d030
--- /dev/null
+++ b/src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/UnusedVirtualMethodAnnotations.cs
@@ -0,0 +1,84 @@
+// 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.Helpers;
+
+namespace Mono.Linker.Tests.Cases.DataFlow
+{
+    [SkipKeptItemsValidation]
+    [ExpectedNoWarnings]
+    class UnusedVirtualMethodAnnotations
+    {
+        [UnconditionalSuppressMessage("Test", "IL2026")]
+        public static void Main()
+        {
+            _ = typeof(TypeOnlyImplementation);
+
+            IUsed used = new UsedImplementation();
+            used.Method(typeof(object));
+
+            IPartiallyUsed partiallyUsed = new PartiallyUsedImplementation();
+            partiallyUsed.Method(typeof(object));
+        }
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)]
+        interface IUnused
+        {
+            [RequiresUnreferencedCode(nameof(Method))]
+            void Method([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)] Type type);
+        }
+
+        class UnusedImplementation : IUnused
+        {
+            public void Method(Type type) { }
+        }
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)]
+        interface ITypeOnly
+        {
+            [RequiresUnreferencedCode(nameof(Method))]
+            void Method([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)] Type type);
+        }
+
+        class TypeOnlyImplementation : ITypeOnly
+        {
+            public void Method(Type type) { }
+        }
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)]
+        interface IUsed
+        {
+            [RequiresUnreferencedCode(nameof(Method))]
+            void Method([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)] Type type);
+        }
+
+        class UsedImplementation : IUsed
+        {
+            [ExpectedWarning("IL2046")]
+            [ExpectedWarning("IL2092")]
+            public void Method(Type type) { }
+        }
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)]
+        interface IPartiallyUsed
+        {
+            [RequiresUnreferencedCode(nameof(Method))]
+            void Method([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods)] Type type);
+        }
+
+        class PartiallyUsedImplementation : IPartiallyUsed
+        {
+            [ExpectedWarning("IL2046")]
+            [ExpectedWarning("IL2092")]
+            public void Method(Type type) { }
+        }
+
+        class UnusedImplementationOfPartiallyUsedInterface : IPartiallyUsed
+        {
+            public void Method(Type type) { }
+        }
+    }
+}