# Wednesday, 18 July 2012
« IKVM.NET 7.1 Released | Main | New Development Snapshot »
New Development Snapshot

I've been working on IKVM.Reflection to fix some loose ends and add support for various .NET 4.5 features. I also managed to squeeze in some bug fixes for IKVM.NET itself and some improvements to the (experimental and disabled by default) MSIL optimizer. Finally, I added intrinsics for some sun.misc.Unsafe operations to make some of the java.util.concurrent classes more efficient.


  • Bug fix. The interface fields exposed in the __Fields nested type should have a public field type.
  • Interface fields can always be marked as initonly and don't need final access stubs.
  • Disable AppDomain.ProcessExit hook to run shutdown hooks when running on Mono to workaround https://bugzilla.xamarin.com/show_bug.cgi?id=5650
  • Changed NoClassDefFoundError resulting from type initialization failure to be consistent with OpenJDK behavior.
  • Many improvements to the (disabled) MSIL optimizer.
  • Added intrinsics for (some usages of) Unsafe methods: putObject, putOrderedObject, putObjectVolatile, getObjectVolatile, getObject, compareAndSwapObject.
  • Marked String.compareTo(Object) as bridge method.
  • Remove org.omg.PortableInterceptor.UNKNOWN class, that is not part of [Open]JDK rt.jar.
  • Add ZipFile constructor that was added in Java 7.
  • Deprecated the ikvmstub -serialver option and added a -japi option instead that also adds non-public interfaces and members. Also added a hack to fix the fact that String instance methods were all marked as deprecated.
  • Internal stub generator now reproduces exact class modifier bits.
  • Unused class modifier bits are now properly masked and returned.
  • Non-abstract interfaces now properly return ACC_ABSTRACT modifier.
  • IKVM.Reflection: Added .NET 4.5 ModuleBuilder APIs GetMethodToken(MethodInfo, IEnumerable) and GetConstructorToken(MethodInfo, IEnumerable).
  • IKVM.Reflection: Added API extensions ModuleBuilder.__GetMethodToken() and ModuleBuilder.__GetConstructorToken().
  • IKVM.Reflection: Bug fix. SignatureHelper.AddArguments() should accept a null reference for arguments parameter.
  • IKVM.Reflection: Bug fix. SignatureHelper.GetMethodSigHelper(Module, Type, Type[]) should accept null reference for parameterTypes argument.
  • IKVM.Reflection: Bug fix. SignatureHelper.AddArguments(Type[], Type[][], Type[][]) should accept null references for requiredCustomModifiers and optionalCustomModifiers.
  • IKVM.Reflection: Bug fix. SignatureHelper.AddSentinel() should not affect the calling convention.
  • IKVM.Reflection: Simplified SignatureHelper implementation to make it more compatible with .NET and more efficient.
  • IKVM.Reflection: Added .NET 4.5 AssemblyName.ContentType property and ContentType=WindowsRuntime in AssemblyName.
  • IKVM.Reflection: Bug fix. ModuleBuilder.ResolveMethod() should return ConstructorInfo for constructors.
  • IKVM.Reflection: Made MethodSpec handling more consistent with MemberRef handling. This avoids the need for the caching the MethodInfo to token mappings (which leaks memory, because generic method instances are not canonicalized).
  • IKVM.Reflection: Removed unnecessary (and memory leaking) member ref caching level.
  • IKVM.Reflection: Explicitly disallow modifying a method signature after it has been used.
  • IKVM.Reflection: Added experimental support for generating Windows Runtime (.winmd) assemblies.
  • IKVM.Reflection: Added missing DefineResource() APIs to ModuleBuilder and AssemblyBuilder.
  • IKVM.Reflection: Fixed regression. Type.GetConstructor() should also return the class constructor. This also fixes Type.TypeInitializer.
  • IKVM.Reflection: Updated Assembly.CreateQualifiedName() to be compatible with current .NET versions.
  • IKVM.Reflection: Added new .NET 4.5 API Type.IsConstructedGenericType.
  • IKVM.Reflection: Added co-/contra-variance support to Type.IsAssignableFrom().
  • IKVM.Reflection: Added support for using the .NETCore v4.5 aka Metro profile mscorlib.dll.
  • IKVM.Reflection: Ignore HasFieldMarshal attribute and always return the pseudo custom attribute if a FieldMarshal record exists. This is similar to .NET reflection.
  • IKVM.Reflection: If a FieldLayout record exists, always return the pseudo custom attribute FieldOffset, regardless of the declaring type's layout.
  • IKVM.Reflection: Added new API [Field|Parameter]Info.__TryGetFieldMarshal().
  • IKVM.Reflection: Added new API FieldInfo.__TryGetFieldOffset().
  • IKVM.Reflection: Keep track of whether a ModuleBuilder has been saved (and only allow it to be saved once).
  • IKVM.Reflection: Fixed various builders to throw NotImplementedException (like .NET) when getting custom attributes before the type has been baked.
  • IKVM.Reflection: Fixed various builders to properly return custom attributes after the module has been saved.
  • IKVM.Reflection: Bug fix. FieldBuilder.GetRawConstantValue() didn't work after saving the module.
  • IKVM.Reflection: Bug fix. MethodInfo should return PreserveSigAttribute pseudo custom attribute if MethodImplAttributes.PreserveSig is set.
  • IKVM.Reflection: Added new API MethodInfo.__TryGetImplMap().
  • IKVM.Reflection: Changed DllImportAttribute synthesis to always include CharSet, BestFitMapping and ThrowOnUnmappableChar to be compatible with .NET. Now that we have __TryGetImplMap() we don't need to distinguish anymore between not set and set to the default value.
  • IKVM.Reflection: Added .NET 4.5 API CustomAttributeData.AttributeType property.
  • IKVM.Reflection: Made MarshalAsAttribute synthesis more compatible with .NET by always setting ArraySubType, SizeParamIndex, SizeConst and SafeArraySubType properties.
  • IKVM.Reflection: Made CustomAttributeData.ToString() output more compatible with .NET (by "casting" enum values, except zero).
  • IKVM.Reflection: Fixed MarshalAsAttribute values. Use enum underlying values, instead of the enum values.
  • IKVM.Reflection: Added UniverseOptions.DisablePseudoCustomAttributeRetrieval to disable returning pseudo custom attributes.

Binaries available here: ikvmbin-7.2.4582.zip

Wednesday, 18 July 2012 08:35:08 (W. Europe Daylight Time, UTC+02:00)  #    Comments [2]
Friday, 20 July 2012 01:38:01 (W. Europe Daylight Time, UTC+02:00)

I'm trying to convert an applet to a dll. When I try to, an exception is thrown:

System.NotSupportedException: 'Backward branch constraints' violated
at IKVM.Reflection.Emit.ILGenerator.Emit(OpCode opc, Label label)
at IKVM.Internal.CodeEmitter.RealEmitOpCode(OpCode opcode, Object arg)
at IKVM.Internal.CodeEmitter.DoEmit()
at IKVM.Internal.DynamicTypeWrapper.FinishContext.FinishImpl()
at IKVM.Internal.DynamicTypeWrapper.JavaTypeImpl.FinishCore()
at IKVM.Internal.DynamicTypeWrapper.JavaTypeImpl.Finish()
at IKVM.Internal.AotTypeWrapper.Finish()
at IKVM.Internal.DynamicClassLoader.FinishAll()
at IKVM.Internal.CompilerClassLoader.Compile(String runtimeAssembly, List`1
at IkvmcCompiler.Compile(String[] args)
at IkvmcCompiler.Main(String[] args)

It would be nice if you reply and try to fix it.
Tuesday, 24 July 2012 08:13:01 (W. Europe Daylight Time, UTC+02:00)
Thanks for reporting this. The bug is fixed in the new development snapshot:
Home page

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Anti-Spam Question: What method on java.lang.System returns an object's original hashcode (i.e. the one that would be returned by java.lang.Object.hashCode() if it wasn't overridden)? (case is significant)

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