From e2e66e0eec59e8692f95977f2a867ed8f9d67785 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Fri, 30 Dec 2022 00:08:32 +0100
Subject: [PATCH] Fix crash when unboxing integer value type from managed
 callback via generated bindings

---
 .../Bindings/BindingsGenerator.Cpp.cs         | 25 ++++++++++++++-----
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs b/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs
index 624f54d39..0fd5ead49 100644
--- a/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs
+++ b/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs
@@ -1277,7 +1277,8 @@ namespace Flax.Build.Bindings
                 thunkCall += GenerateCppWrapperNativeToBox(buildData, parameterInfo.Type, classInfo, parameterInfo.Name);
             }
 
-            if (functionInfo.ReturnType.IsVoid)
+            var returnType = functionInfo.ReturnType;
+            if (returnType.IsVoid)
             {
                 contents.AppendLine($"        typedef void (*Thunk)(void* instance{thunkParams}, MonoObject** exception);");
                 contents.AppendLine("        const auto thunk = (Thunk)method->GetThunk();");
@@ -1295,18 +1296,30 @@ namespace Flax.Build.Bindings
             contents.AppendLine("        if (exception)");
             contents.AppendLine("            DebugLog::LogException(exception);");
 
-            if (!functionInfo.ReturnType.IsVoid)
+            if (!returnType.IsVoid)
             {
-                if (functionInfo.ReturnType.IsRef)
+                if (returnType.IsRef)
                     throw new NotSupportedException($"Passing return value by reference is not supported for virtual API methods. Used on method '{functionInfo}'.");
 
-                switch (functionInfo.ReturnType.Type)
+                switch (returnType.Type)
                 {
                 case "bool":
-                    contents.AppendLine($"        return __result != 0;");
+                    contents.AppendLine("        return __result != 0;");
+                    break;
+                case "int8":
+                case "int16":
+                case "int32":
+                case "int64":
+                    contents.AppendLine($"        return ({returnType.Type})(intptr)__result;");
+                    break;
+                case "uint8":
+                case "uint16":
+                case "uint32":
+                case "uint64":
+                    contents.AppendLine($"        return ({returnType.Type})(uintptr)__result;");
                     break;
                 default:
-                    contents.AppendLine($"        return MUtils::Unbox<{functionInfo.ReturnType}>(__result);");
+                    contents.AppendLine($"        return MUtils::Unbox<{returnType}>(__result);");
                     break;
                 }
             }