From 39505475d60d651aa06f02cdd5ad5203f974bb93 Mon Sep 17 00:00:00 2001
From: ds5678 <49847914+ds5678@users.noreply.github.com>
Date: Sat, 14 Sep 2024 23:32:56 -0700
Subject: [PATCH] Handle unboxing for generic parameters

---
 Il2CppInterop.Generator/Utils/UnstripTranslator.cs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Il2CppInterop.Generator/Utils/UnstripTranslator.cs b/Il2CppInterop.Generator/Utils/UnstripTranslator.cs
index fe1a5261..ee9ce42c 100644
--- a/Il2CppInterop.Generator/Utils/UnstripTranslator.cs
+++ b/Il2CppInterop.Generator/Utils/UnstripTranslator.cs
@@ -214,8 +214,12 @@ public static bool TranslateMethod(MethodDefinition original, MethodDefinition t
                 if (targetType == null)
                     return false;
 
-                if (bodyInstruction.OpCode == OpCodes.Castclass && !targetType.IsValueType)
+                if ((bodyInstruction.OpCode == OpCodes.Castclass && !targetType.IsValueType) ||
+                    (bodyInstruction.OpCode == OpCodes.Unbox_Any && targetType is GenericParameterSignature))
                 {
+                    // Compilers use unbox.any for casting to generic parameter types.
+                    // Castclass is only used for reference types.
+                    // Both can be translated to Il2CppObjectBase.Cast<T>().
                     var newInstruction = targetBuilder.Add(OpCodes.Call,
                         imports.Module.DefaultImporter.ImportMethod(imports.Il2CppObjectBase_Cast.Value.MakeGenericInstanceMethod(targetType)));
                     instructionMap.Add(bodyInstruction, newInstruction);