context: //
  // method.cs: Method based declarations
  //
  // Authors: Miguel de Icaza (miguel@gnu.org)
  //          Martin Baulig (martin@ximian.com)
  //          Marek Safar (marek.safar@gmail.com)
  //
  // Dual licensed under the terms of the MIT X11 or GNU GPL
  //
  // Copyright 2001, 2002, 2003 Ximian, Inc (http://www.ximian.com)
  // Copyright 2004-2008 Novell, Inc
  //
  
  using System;
  using System.Collections.Generic;
  using System.Security;
  using System.Security.Permissions;
  using System.Text;
  using System.Linq;
  
  #if NET_2_1
  using XmlElement = System.Object;
  #else
  using System.Xml;
  #endif
  
  #if STATIC
  using MetaType = IKVM.Reflection.Type;
  using SecurityType = System.Collections.Generic.List<IKVM.Reflection.Emit.CustomAttributeBuilder>;
  using IKVM.Reflection;
  using IKVM.Reflection.Emit;
  #else
  using MetaType = System.Type;
  using SecurityType = System.Collections.Generic.Dictionary<System.Security.Permissions.SecurityAction, System.Security.PermissionSet>;
  using System.Reflection;
  using System.Reflection.Emit;
  #endif
  
  using Mono.CompilerServices.SymbolWriter;
  
  namespace Mono.CSharp {
  
  	public abstract class MethodCore : InterfaceMemberBase, IParametersMember
  	{
  		protected ParametersCompiled parameters;
  		protected ToplevelBlock block;
  		protected MethodSpec spec;
  
  		public MethodCore (DeclSpace parent, GenericMethod generic,
  			FullNamedExpression type, Modifiers mod, Modifiers allowed_mod,
  			MemberName name, Attributes attrs, ParametersCompiled parameters)
  			: base (parent, generic, type, mod, allowed_mod, name, attrs)
  		{
  			this.parameters = parameters;
  		}
  
  		public override Variance ExpectedMemberTypeVariance {
  			get {
  				return Variance.Covariant;
  			}
  		}
  
  		//
  		//  Returns the System.Type array for the parameters of this method
  		//
  		public TypeSpec [] ParameterTypes {
  			get {
  				return parameters.Types;
  			}
  		}
  
  		public ParametersCompiled ParameterInfo {
  			get {
  				return parameters;
  			}
  		}
  
  		AParametersCollection IParametersMember.Parameters {
  			get { return parameters; }
  		}
  		
  		public ToplevelBlock Block {
  			get {
  				return block;
  			}
  
  			set {
  				block = value;
  			}
  		}
  
  		public CallingConventions CallingConventions {
  			get {
  				CallingConventions cc = parameters.CallingConvention;
  				if (!IsInterface)
  					if ((ModFlags & Modifiers.STATIC) == 0)
  						cc |= CallingConventions.HasThis;
  
  				// FIXME: How is `ExplicitThis' used in C#?
  			
  				return cc;
  			}
  		}
  
  		protected override bool CheckOverrideAgainstBase (MemberSpec base_member)
  		{
  			bool res = base.CheckOverrideAgainstBase (base_member);
  
  			//
  			// Check that the permissions are not being changed
  			//
  			if (!CheckAccessModifiers (this, base_member)) {
  				Error_CannotChangeAccessModifiers (this, base_member);
  				res = false;
  			}
  
  			return res;
  		}
  
  		protected override bool CheckBase ()
  		{
  			// Check whether arguments were correct.
  			if (!DefineParameters (parameters))
  				return false;
  
  			return base.CheckBase ();
  		}
  
  		//
  		//   Represents header string for documentation comment.
  		//
  		public override string DocCommentHeader 
  		{
  			get { return "M:"; }
  		}
  
  		public override bool EnableOverloadChecks (MemberCore overload)
  		{
  			if (overload is MethodCore) {
  				caching_flags |= Flags.MethodOverloadsExist;
  				return true;
  			}
  
  			if (overload is AbstractPropertyEventMethod)
  				return true;
  
  			return base.EnableOverloadChecks (overload);
  		}
  
  		public override string GetSignatureForDocumentation ()
  		{
  			string s = base.GetSignatureForDocumentation ();
  			if (MemberName.Arity > 0)
  				s += "``" + MemberName.Arity.ToString ();
  
  			return s + parameters.GetSignatureForDocumentation ();
  		}
  
  		public MethodSpec Spec {
  			get { return spec; }
  		}
  
  		protected override bool VerifyClsCompliance ()
  		{
  			if (!base.VerifyClsCompliance ())
  				return false;
  
  			if (parameters.HasArglist) {
  				Report.Warning (3000, 1, Location, "Methods with variable arguments are not CLS-compliant");
  			}
  
  			if (member_type != null && !member_type.IsCLSCompliant ()) {
  				Report.Warning (3002, 1, Location, "Return type of `{0}' is not CLS-compliant",
  					GetSignatureForError ());
  			}
  
  			parameters.VerifyClsCompliance (this);
  			return true;
  		}
  	}
  
  	public interface IGenericMethodDefinition : IMemberDefinition
  	{
  		TypeParameterSpec[] TypeParameters { get; }
  		int TypeParametersCount { get; }
  
  //		MethodInfo MakeGenericMethod (TypeSpec[] targs);
  	}
  
  	public sealed class MethodSpec : MemberSpec, IParametersMember
  	{
  		MethodBase metaInfo, inflatedMetaInfo;
  		AParametersCollection parameters;
  		TypeSpec returnType;
  
  		TypeSpec[] targs;
  		TypeParameterSpec[] constraints;
  
  		public MethodSpec (MemberKind kind, TypeSpec declaringType, IMemberDefinition details, TypeSpec returnType,
  			MethodBase info, AParametersCollection parameters, Modifiers modifiers)
  			: base (kind, declaringType, details, modifiers)
  		{
  			this.metaInfo = info;
  			this.parameters = parameters;
  			this.returnType = returnType;
  		}
  
  		#region Properties
  
  		public override int Arity {
  			get {
  				return IsGeneric ? GenericDefinition.TypeParametersCount : 0;
  			}
  		}
  
  		public TypeParameterSpec[] Constraints {
  			get {
  				if (constraints == null && IsGeneric)
  					constraints = GenericDefinition.TypeParameters;
  
  				return constraints;
  			}
  		}
  
  		public bool IsConstructor {
  			get {
  				return Kind == MemberKind.Constructor;
  			}
  		}
  
  		public IGenericMethodDefinition GenericDefinition {
  			get {
  				return (IGenericMethodDefinition) definition;
  			}
  		}
  
  		public bool IsExtensionMethod {
  			get {
  				return IsStatic && parameters.HasExtensionMethodType;
  			}
  		}
  
  		public bool IsSealed {
  			get {
  				return (Modifiers & Modifiers.SEALED) != 0;
  			}
  		}
  
  		// When is virtual or abstract
  		public bool IsVirtual {
  			get {
  				return (Modifiers & (Modifiers.VIRTUAL | Modifiers.ABSTRACT | Modifiers.OVERRIDE)) != 0;
  			}
  		}
  
  		public bool IsReservedMethod {
  			get {
  				return Kind == MemberKind.Operator || IsAccessor;
  			}
  		}
  
  		TypeSpec IInterfaceMemberSpec.MemberType {
  			get {
  				return returnType;
  			}
  		}
  
  		public AParametersCollection Parameters {
  			get { 
  				return parameters;
  			}
  		}
  
  		public TypeSpec ReturnType {
  			get {
  				return returnType;
  			}
  		}
  
  		public TypeSpec[] TypeArguments {
  			get {
  				return targs;
  			}
  		}
  
  		#endregion
  
  		public MethodSpec GetGenericMethodDefinition ()
  		{
  			if (!IsGeneric && !DeclaringType.IsGeneric)
  				return this;
  
  			return MemberCache.GetMember (declaringType, this);
  		}
  
  		public MethodBase GetMetaInfo ()
  		{
  			//
  			// inflatedMetaInfo is extra field needed for cases where we
  			// inflate method but another nested type can later inflate
  			// again (the cache would be build with inflated metaInfo) and
  			// TypeBuilder can work with method definitions only
  			//
  			if (inflatedMetaInfo == null) {
  				if ((state & StateFlags.PendingMetaInflate) != 0) {
  					var dt_meta = DeclaringType.GetMetaInfo ();
  
  					if (DeclaringType.IsTypeBuilder) {
  						if (IsConstructor)
  							inflatedMetaInfo = TypeBuilder.GetConstructor (dt_meta, (ConstructorInfo) metaInfo);
  						else
  							inflatedMetaInfo = TypeBuilder.GetMethod (dt_meta, (MethodInfo) metaInfo);
  					} else {
  #if STATIC
  						// it should not be reached
  						throw new NotImplementedException ();
  #else
  						inflatedMetaInfo = MethodInfo.GetMethodFromHandle (metaInfo.MethodHandle, dt_meta.TypeHandle);
  #endif
  					}
  
  					state &= ~StateFlags.PendingMetaInflate;
  				} else {
  					inflatedMetaInfo = metaInfo;
  				}
  			}
  
  			if ((state & StateFlags.PendingMakeMethod) != 0) {
  				var sre_targs = new MetaType[targs.Length];
  				for (int i = 0; i < sre_targs.Length; ++i)
  					sre_targs[i] = targs[i].GetMetaInfo ();
  
  				inflatedMetaInfo = ((MethodInfo) inflatedMetaInfo).MakeGenericMethod (sre_targs);
  				state &= ~StateFlags.PendingMakeMethod;
  			}
  
  			return inflatedMetaInfo;
  		}
  
  		public override string GetSignatureForDocumentation ()
  		{
  			string name;
  			switch (Kind) {
  			case MemberKind.Constructor:
  				name = "#ctor";
  				break;
  			case MemberKind.Method:
  				if (Arity > 0)
  					name = Name + "``" + Arity.ToString ();
  				else
  					name = Name;
  
  				break;
  			default:
  				name = Name;
  				break;
  			}
  
  			name = DeclaringType.GetSignatureForDocumentation () + "." + name + parameters.GetSignatureForDocumentation ();
  			if (Kind == MemberKind.Operator) {
  				var op = Operator.GetType (Name).Value;
  				if (op == Operator.OpType.Explicit || op == Operator.OpType.Implicit) {
  					name += "~" + ReturnType.GetSignatureForDocumentation ();
  				}
  			}
  
  			return name;
  		}
  
  		public override string GetSignatureForError ()
  		{
  			string name;
  			if (IsConstructor) {
  				name = DeclaringType.GetSignatureForError () + "." + DeclaringType.Name;
  			} else if (Kind == MemberKind.Operator) {
  				var op = Operator.GetType (Name).Value;
  				if (op == Operator.OpType.Implicit || op == Operator.OpType.Explicit) {
  					name = DeclaringType.GetSignatureForError () + "." + Operator.GetName (op) + " operator " + returnType.GetSignatureForError ();
  				} else {
  					name = DeclaringType.GetSignatureForError () + ".operator " + Operator.GetName (op);
  				}
  			} else if (IsAccessor) {
  				int split = Name.IndexOf ('_');
  				name = Name.Substring (split + 1);
  				var postfix = Name.Substring (0, split);
  				if (split == 3) {
  					var pc = parameters.Count;
  					if (pc > 0 && postfix == "get") {
  						name = "this" + parameters.GetSignatureForError ("[", "]", pc);
  					} else if (pc > 1 && postfix == "set") {
  						name = "this" + parameters.GetSignatureForError ("[", "]", pc - 1);
  					}
  				}
  
  				return DeclaringType.GetSignatureForError () + "." + name + "." + postfix;
  			} else {
  				name = base.GetSignatureForError ();
  				if (targs != null)
  					name += "<" + TypeManager.CSharpName (targs) + ">";
  				else if (IsGeneric)
  					name += "<" + TypeManager.CSharpName (GenericDefinition.TypeParameters) + ">";
  			}
  
  			return name + parameters.GetSignatureForError ();
  		}
  
  		public override MemberSpec InflateMember (TypeParameterInflator inflator)
  		{
  			var ms = (MethodSpec) base.InflateMember (inflator);
  			ms.inflatedMetaInfo = null;
  			ms.returnType = inflator.Inflate (returnType);
  			ms.parameters = parameters.Inflate (inflator);
  			if (IsGeneric)
  				ms.constraints = TypeParameterSpec.InflateConstraints (inflator, Constraints);
  
  			return ms;
  		}
  
  		public MethodSpec MakeGenericMethod (IMemberContext context, params TypeSpec[] targs)
  		{
  			if (targs == null)
  				throw new ArgumentNullException ();
  // TODO MemberCache
  //			if (generic_intances != null && generic_intances.TryGetValue (targs, out ginstance))
  //				return ginstance;
  
  			//if (generic_intances == null)
  			//    generic_intances = new Dictionary<TypeSpec[], Method> (TypeSpecArrayComparer.Default);
  
  			var inflator = new TypeParameterInflator (context, DeclaringType, GenericDefinition.TypeParameters, targs);
  
  			var inflated = (MethodSpec) MemberwiseClone ();
  			inflated.declaringType = inflator.TypeInstance;
  			inflated.returnType = inflator.Inflate (returnType);
  			inflated.parameters = parameters.Inflate (inflator);
  			inflated.targs = targs;
  			inflated.constraints = TypeParameterSpec.InflateConstraints (inflator, constraints ?? GenericDefinition.TypeParameters);
  			inflated.state |= StateFlags.PendingMakeMethod;
  
  			//			if (inflated.parent == null)
  			//				inflated.parent = parent;
  
  			//generic_intances.Add (targs, inflated);
  			return inflated;
  		}
  
  		public MethodSpec Mutate (TypeParameterMutator mutator)
  		{
  			var targs = TypeArguments;
  			if (targs != null)
  				targs = mutator.Mutate (targs);
  
  			var decl = DeclaringType;
  			if (DeclaringType.IsGenericOrParentIsGeneric) {
  				decl = mutator.Mutate (decl);
  			}
  
  			if (targs == TypeArguments && decl == DeclaringType)
  				return this;
  
  			var ms = (MethodSpec) MemberwiseClone ();
  			if (decl != DeclaringType) {
  				ms.inflatedMetaInfo = null;
  				ms.declaringType = decl;
  				ms.state |= StateFlags.PendingMetaInflate;
  			}
  
  			if (targs != null) {
  				ms.targs = targs;
  				ms.state |= StateFlags.PendingMakeMethod;
  			}
  
  			return ms;
  		}
  
  		public override List<TypeSpec> ResolveMissingDependencies ()
  		{
  			var missing = returnType.ResolveMissingDependencies ();
  			foreach (var pt in parameters.Types) {
  				var m = pt.GetMissingDependencies ();
  				if (m == null)
  					continue;
  
  				if (missing == null)
  					missing = new List<TypeSpec> ();
  
  				missing.AddRange (m);
  			}
  
  			return missing;			
  		}
  
  		public void SetMetaInfo (MethodInfo info)
  		{
  			if (this.metaInfo != null)
  				throw new InternalErrorException ("MetaInfo reset");
  
  			this.metaInfo = info;
  		}
  	}
  
  	public abstract class MethodOrOperator : MethodCore, IMethodData
  	{
  		public MethodBuilder MethodBuilder;
  		ReturnParameter return_attributes;
  		SecurityType declarative_security;
  		protected MethodData MethodData;
  
  		static readonly string[] attribute_targets = new string [] { "method", "return" };
  
  		protected MethodOrOperator (DeclSpace parent, GenericMethod generic, FullNamedExpression type, Modifiers mod,
  				Modifiers allowed_mod, MemberName name,
  				Attributes attrs, ParametersCompiled parameters)
  			: base (parent, generic, type, mod, allowed_mod, name,
  					attrs, parameters)
  		{
  		}
  
  		public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
  		{
  			if (a.Target == AttributeTargets.ReturnValue) {
  				if (return_attributes == null)
  					return_attributes = new ReturnParameter (this, MethodBuilder, Location);
  
  				return_attributes.ApplyAttributeBuilder (a, ctor, cdata, pa);
  				return;
  			}
  
  			if (a.Type == pa.MethodImpl) {
  				is_external_implementation = a.IsInternalCall ();
  			}
  
  			if (a.Type == pa.DllImport) {
  				const Modifiers extern_static = Modifiers.EXTERN | Modifiers.STATIC;
  				if ((ModFlags & extern_static) != extern_static) {
  					Report.Error (601, a.Location, "The DllImport attribute must be specified on a method marked `static' and `extern'");
  				}
  				is_external_implementation = true;
  			}
  
  			if (a.IsValidSecurityAttribute ()) {
  				a.ExtractSecurityPermissionSet (ctor, ref declarative_security);
  				return;
  			}
  
  			if (MethodBuilder != null)
  				MethodBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), cdata);
  		}
  
  		public override AttributeTargets AttributeTargets {
  			get {
  				return AttributeTargets.Method; 
  			}
  		}
  
  		protected override bool CheckForDuplications ()
  		{
  			return Parent.MemberCache.CheckExistingMembersOverloads (this, parameters);
  		}
  
  		public virtual EmitContext CreateEmitContext (ILGenerator ig)
  		{
  			return new EmitContext (this, ig, MemberType);
  		}
  
  		public override bool Define ()
  		{
  			if (!base.Define ())
  				return false;
  
  			if (!CheckBase ())
  				return false;
  
  			MemberKind kind;
  			if (this is Operator)
  				kind = MemberKind.Operator;
  			else if (this is Destructor)
  				kind = MemberKind.Destructor;
  			else
  				kind = MemberKind.Method;
  
  			if (IsPartialDefinition) {
  				caching_flags &= ~Flags.Excluded_Undetected;
  				caching_flags |= Flags.Excluded;
  
  				// Add to member cache only when a partial method implementation has not been found yet
  				if ((caching_flags & Flags.PartialDefinitionExists) == 0) {
  //					MethodBase mb = new PartialMethodDefinitionInfo (this);
  
  					spec = new MethodSpec (kind, Parent.Definition, this, ReturnType, null, parameters, ModFlags);
  					Parent.MemberCache.AddMember (spec);
  				}
  
  				return true;
  			}
  
  			MethodData = new MethodData (
  				this, ModFlags, flags, this, MethodBuilder, GenericMethod, base_method);
  
  			if (!MethodData.Define (Parent.PartialContainer, GetFullName (MemberName), Report))
  				return false;
  					
  			MethodBuilder = MethodData.MethodBuilder;
  
  			spec = new MethodSpec (kind, Parent.Definition, this, ReturnType, MethodBuilder, parameters, ModFlags);
  			if (MemberName.Arity > 0)
  				spec.IsGeneric = true;
  			
  			Parent.MemberCache.AddMember (this, MethodBuilder.Name, spec);
  
  			return true;
  		}
  
  		protected override void DoMemberTypeIndependentChecks ()
  		{
  			base.DoMemberTypeIndependentChecks ();
  
  			CheckAbstractAndExtern (block != null);
  
  			if ((ModFlags & Modifiers.PARTIAL) != 0) {
  				for (int i = 0; i < parameters.Count; ++i) {
  					IParameterData p = parameters.FixedParameters [i];
  					if (p.ModFlags == Parameter.Modifier.OUT) {
  						Report.Error (752, Location, "`{0}': A partial method parameters cannot use `out' modifier",
  							GetSignatureForError ());
  					}
  
  					if (p.HasDefaultValue && IsPartialImplementation)
  						((Parameter) p).Warning_UselessOptionalParameter (Report);
  				}
  			}
  		}
  
  		protected override void DoMemberTypeDependentChecks ()
  		{
  			base.DoMemberTypeDependentChecks ();
  
  			if (MemberType.IsStatic) {
  				Error_StaticReturnType ();
  			}
  		}
  
  		public override void Emit ()
  		{
  			if ((ModFlags & Modifiers.COMPILER_GENERATED) != 0 && !Parent.IsCompilerGenerated)
  				Module.PredefinedAttributes.CompilerGenerated.EmitAttribute (MethodBuilder);
  			if ((ModFlags & Modifiers.DEBUGGER_HIDDEN) != 0)
  				Module.PredefinedAttributes.DebuggerHidden.EmitAttribute (MethodBuilder);
  
  			if (ReturnType.BuiltinType == BuiltinTypeSpec.Type.Dynamic) {
  				return_attributes = new ReturnParameter (this, MethodBuilder, Location);
  				Module.PredefinedAttributes.Dynamic.EmitAttribute (return_attributes.Builder);
  			} else if (ReturnType.HasDynamicElement) {
  				return_attributes = new ReturnParameter (this, MethodBuilder, Location);
  				Module.PredefinedAttributes.Dynamic.EmitAttribute (return_attributes.Builder, ReturnType, Location);
  			}
  
  			if (OptAttributes != null)
  				OptAttributes.Emit ();
  
  			if (declarative_security != null) {
  				foreach (var de in declarative_security) {
  #if STATIC
  					MethodBuilder.__AddDeclarativeSecurity (de);
  #else
  					MethodBuilder.AddDeclarativeSecurity (de.Key, de.Value);
  #endif
  				}
  			}
  
  			if (MethodData != null)
  				MethodData.Emit (Parent);
  
  			base.Emit ();
  
  			Block = null;
  			MethodData = null;
  		}
  
  		protected void Error_ConditionalAttributeIsNotValid ()
  		{
  			Report.Error (577, Location,
  				"Conditional not valid on `{0}' because it is a constructor, destructor, operator or explicit interface implementation",
  				GetSignatureForError ());
  		}
  
  		public bool IsPartialDefinition {
  			get {
  				return (ModFlags & Modifiers.PARTIAL) != 0 && Block == null;
  			}
  		}
  
  		public bool IsPartialImplementation {
  			get {
  				return (ModFlags & Modifiers.PARTIAL) != 0 && Block != null;
  			}
  		}
  
  		public override string[] ValidAttributeTargets {
  			get {
  				return attribute_targets;
  			}
  		}
  
  		#region IMethodData Members
  
  		public TypeSpec ReturnType {
  			get {
  				return MemberType;
  			}
  		}
  
  		public MemberName MethodName {
  			get {
  				return MemberName;
  			}
  		}
  
  		/// <summary>
  		/// Returns true if method has conditional attribute and the conditions is not defined (method is excluded).
  		/// </summary>
  		public override string[] ConditionalConditions ()
  		{
  			if ((caching_flags & (Flags.Excluded_Undetected | Flags.Excluded)) == 0)
  				return null;
  
  			if ((ModFlags & Modifiers.PARTIAL) != 0 && (caching_flags & Flags.Excluded) != 0)
  				return new string [0];
  
  			caching_flags &= ~Flags.Excluded_Undetected;
  			string[] conditions;
  
  			if (base_method == null) {
  				if (OptAttributes == null)
  					return null;
  
  				Attribute[] attrs = OptAttributes.SearchMulti (Module.PredefinedAttributes.Conditional);
  				if (attrs == null)
  					return null;
  
  				conditions = new string[attrs.Length];
  				for (int i = 0; i < conditions.Length; ++i)
  					conditions[i] = attrs[i].GetConditionalAttributeValue ();
  			} else {
  				conditions = base_method.MemberDefinition.ConditionalConditions();
  			}
  
  			if (conditions != null)
  				caching_flags |= Flags.Excluded;
  
  			return conditions;
  		}
  
  		GenericMethod IMethodData.GenericMethod {
  			get {
  				return GenericMethod;
  			}
  		}
  
  		public virtual void EmitExtraSymbolInfo (SourceMethod source)
  		{ }
  
  		#endregion
  
  	}
  
  	public class SourceMethod : IMethodDef
  	{
  		MethodBase method;
  		SourceMethodBuilder builder;
  
  		protected SourceMethod (DeclSpace parent, MethodBase method, ICompileUnit file)
  		{
  			this.method = method;
  			
  			builder = SymbolWriter.OpenMethod (file, parent.NamespaceEntry.SymbolFileID, this);
  		}
  
  		public string Name {
  			get { return method.Name; }
  		}
  
  		public int Token {
  			get {
  				MethodToken token;
  				var mb = method as MethodBuilder;
  				if (mb != null)
  					token = mb.GetToken ();
  				else
  					token = ((ConstructorBuilder) method).GetToken ();
  #if STATIC
  				if (token.IsPseudoToken)
  					return ((ModuleBuilder) method.Module).ResolvePseudoToken (token.Token);
  #endif
  				return token.Token;
  			}
  		}
  
  		public void CloseMethod ()
  		{
  			SymbolWriter.CloseMethod ();
  		}
  
  		public void SetRealMethodName (string name)
  		{
  			if (builder != null)
  				builder.SetRealMethodName (name);
  		}
  
  		public static SourceMethod Create (DeclSpace parent, MethodBase method, Block block)
  		{
  			if (!SymbolWriter.HasSymbolWriter)
  				return null;
  			if (block == null)
  				return null;
  
  			Location start_loc = block.StartLocation;
  			if (start_loc.IsNull)
  				return null;
  
  			ICompileUnit compile_unit = start_loc.CompilationUnit;
  			if (compile_unit == null)
  				return null;
  
  			return new SourceMethod (parent, method, compile_unit);
  		}
  	}
  
  	public class Method : MethodOrOperator, IGenericMethodDefinition
  	{
  		Method partialMethodImplementation;
  
  		public Method (DeclSpace parent, GenericMethod generic,
  			       FullNamedExpression return_type, Modifiers mod,
  			       MemberName name, ParametersCompiled parameters, Attributes attrs)
  			: base (parent, generic, return_type, mod,
  				parent.PartialContainer.Kind == MemberKind.Interface ? AllowedModifiersInterface :
  				parent.PartialContainer.Kind == MemberKind.Struct ? AllowedModifiersStruct :
  				AllowedModifiersClass,
  				name, attrs, parameters)
  		{
  		}
  
  		protected Method (DeclSpace parent, FullNamedExpression return_type, Modifiers mod, Modifiers amod,
  					MemberName name, ParametersCompiled parameters, Attributes attrs)
  			: base (parent, null, return_type, mod, amod, name, attrs, parameters)
  		{
  		}
  
  		#region Properties
  
  		public override TypeParameter[] CurrentTypeParameters {
  			get {
  				if (GenericMethod != null)
  					return GenericMethod.CurrentTypeParameters;
  
  				return null;
  			}
  		}
  
  		public override bool HasUnresolvedConstraints {
  			get {
  				if (CurrentTypeParameters == null)
  					return false;
  
  				// When overriding base method constraints are fetched from
  				// base method but to find it we have to resolve parameters
  				// to find exact base method match
  				if (IsExplicitImpl || (ModFlags & Modifiers.OVERRIDE) != 0)
  					return base_method == null;
  
  				// Even for non-override generic method constraints check has to be
  				// delayed after all constraints are resolved
  				return true;
  			}
  		}
  
  		public TypeParameterSpec[] TypeParameters {
  			get {
  				// TODO: Cache this
  				return CurrentTypeParameters.Select (l => l.Type).ToArray ();
  			}
  		}
  
  		public int TypeParametersCount {
  			get {
  				return CurrentTypeParameters == null ? 0 : CurrentTypeParameters.Length;
  			}
  		}
  
  #endregion
  
  		public override string GetSignatureForError()
  		{
  			return base.GetSignatureForError () + parameters.GetSignatureForError ();
  		}
  
  		void Error_DuplicateEntryPoint (Method b)
  		{
  			Report.Error (17, b.Location,
  				"Program `{0}' has more than one entry point defined: `{1}'",
  				b.Module.Builder.ScopeName, b.GetSignatureForError ());
  		}
  
  		bool IsEntryPoint ()
  		{
  			if (ReturnType.Kind != MemberKind.Void && ReturnType.BuiltinType != BuiltinTypeSpec.Type.Int)
  				return false;
  
  			if (parameters.IsEmpty)
  				return true;
  
  			if (parameters.Count > 1)
  				return false;
  
  			var ac = parameters.Types [0] as ArrayContainer;
  			return ac != null && ac.Rank == 1 && ac.Element.BuiltinType == BuiltinTypeSpec.Type.String &&
  					(parameters[0].ModFlags & ~Parameter.Modifier.PARAMS) == Parameter.Modifier.NONE;
  		}
  
  		public override FullNamedExpression LookupNamespaceOrType (string name, int arity, Location loc, bool ignore_cs0104)
  		{
  			if (arity == 0) {
  				TypeParameter[] tp = CurrentTypeParameters;
  				if (tp != null) {
  					TypeParameter t = TypeParameter.FindTypeParameter (tp, name);
  					if (t != null)
  						return new TypeParameterExpr (t, loc);
  				}
  			}
  
  			return base.LookupNamespaceOrType (name, arity, loc, ignore_cs0104);
  		}
  
  		public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
  		{
  			if (a.Type == pa.Conditional) {
  				if (IsExplicitImpl) {
  					Error_ConditionalAttributeIsNotValid ();
  					return;
  				}
  
  				if ((ModFlags & Modifiers.OVERRIDE) != 0) {
  					Report.Error (243, Location, "Conditional not valid on `{0}' because it is an override method", GetSignatureForError ());
  					return;
  				}
  
  				if (ReturnType.Kind != MemberKind.Void) {
  					Report.Error (578, Location, "Conditional not valid on `{0}' because its return type is not void", GetSignatureForError ());
  					return;
  				}
  
  				if (IsInterface) {
  					Report.Error (582, Location, "Conditional not valid on interface members");
  					return;
  				}
  
  				if (MethodData.implementing != null) {
  					Report.SymbolRelatedToPreviousError (MethodData.implementing.DeclaringType);
  					Report.Error (629, Location, "Conditional member `{0}' cannot implement interface member `{1}'",
  						GetSignatureForError (), TypeManager.CSharpSignature (MethodData.implementing));
  					return;
  				}
  
  				for (int i = 0; i < parameters.Count; ++i) {
  					if (parameters.FixedParameters [i].ModFlags == Parameter.Modifier.OUT) {
  						Report.Error (685, Location, "Conditional method `{0}' cannot have an out parameter", GetSignatureForError ());
  						return;
  					}
  				}
  			}
  
  			if (a.Type == pa.Extension) {
  				a.Error_MisusedExtensionAttribute ();
  				return;
  			}
  
  			base.ApplyAttributeBuilder (a, ctor, cdata, pa);
  		}
  
  		protected virtual void DefineTypeParameters ()
  		{
  			var tparams = CurrentTypeParameters;
  
  			TypeParameterSpec[] base_tparams = null;
  			TypeParameterSpec[] base_decl_tparams = TypeParameterSpec.EmptyTypes;
  			TypeSpec[] base_targs = TypeSpec.EmptyTypes;
  			if (((ModFlags & Modifiers.OVERRIDE) != 0 || IsExplicitImpl)) {
  				if (base_method != null) {
  					base_tparams = base_method.GenericDefinition.TypeParameters;
  				
  					if (base_method.DeclaringType.IsGeneric) {
  						base_decl_tparams = base_method.DeclaringType.MemberDefinition.TypeParameters;
  
  						var base_type_parent = CurrentType;
  						while (base_type_parent.BaseType != base_method.DeclaringType) {
  							base_type_parent = base_type_parent.BaseType;
  						}
  
  						base_targs = base_type_parent.BaseType.TypeArguments;
  					}
  
  					if (base_method.IsGeneric) {
  						ObsoleteAttribute oa;
  						foreach (var base_tp in base_tparams) {
  							oa = base_tp.BaseType.GetAttributeObsolete ();
  							if (oa != null) {
  								AttributeTester.Report_ObsoleteMessage (oa, base_tp.BaseType.GetSignatureForError (), Location, Report);
  							}
  
  							if (base_tp.InterfacesDefined != null) {
  								foreach (var iface in base_tp.InterfacesDefined) {
  									oa = iface.GetAttributeObsolete ();
  									if (oa != null) {
  										AttributeTester.Report_ObsoleteMessage (oa, iface.GetSignatureForError (), Location, Report);
  									}
  								}
  							}
  						}
  
  						if (base_decl_tparams.Length != 0) {
  							base_decl_tparams = base_decl_tparams.Concat (base_tparams).ToArray ();
  							base_targs = base_targs.Concat (tparams.Select<TypeParameter, TypeSpec> (l => l.Type)).ToArray ();
  						} else {
  							base_decl_tparams = base_tparams;
  							base_targs = tparams.Select (l => l.Type).ToArray ();
  						}
  					}
  				} else if (MethodData.implementing != null) {
  					base_tparams = MethodData.implementing.GenericDefinition.TypeParameters;
  					if (MethodData.implementing.DeclaringType.IsGeneric) {
  						base_decl_tparams = MethodData.implementing.DeclaringType.MemberDefinition.TypeParameters;
  						foreach (var iface in Parent.CurrentType.Interfaces) {
  							if (iface == MethodData.implementing.DeclaringType) {
  								base_targs = iface.TypeArguments;
  								break;
  							}
  						}
  					}
  				}
  			}
  
  			for (int i = 0; i < tparams.Length; ++i) {
  				var tp = tparams[i];
  
  				if (!tp.ResolveConstraints (this))
  					continue;
  
  				//
  				// Copy base constraints for override/explicit methods
  				//
  				if (base_tparams != null) {
  					var base_tparam = base_tparams[i];
  					var local_tparam = tp.Type;
  					local_tparam.SpecialConstraint = base_tparam.SpecialConstraint;
  
  					var inflator = new TypeParameterInflator (this, CurrentType, base_decl_tparams, base_targs);
  					base_tparam.InflateConstraints (inflator, local_tparam);
  
  					//
  					// Check all type argument constraints for possible collision
  					// introduced by inflating inherited constraints in this context
  					//
  					// Conflict example:
  					//
  					// class A<T> { virtual void Foo<U> () where U : class, T {} }
  					// class B : A<int> { override void Foo<U> {} }
  					//
  					var local_tparam_targs = local_tparam.TypeArguments;
  					if (local_tparam_targs != null) {					
  						for (int ii = 0; ii < local_tparam_targs.Length; ++ii) {
  							var ta = local_tparam_targs [ii];
  							if (!ta.IsClass && !ta.IsStruct)
  								continue;
  
  							if (Constraints.CheckConflictingInheritedConstraint (local_tparam, ta, this, Location)) {
  								local_tparam.ChangeTypeArgumentToBaseType (ii);
  							}
  						}
  					}
  
  					continue;
  				}
  				
  				if (MethodData.implementing != null) {
  					var base_tp = MethodData.implementing.Constraints[i];
  					if (!tp.Type.HasSameConstraintsImplementation (base_tp)) {
  						Report.SymbolRelatedToPreviousError (MethodData.implementing);
  						Report.Error (425, Location,
  							"The constraints for type parameter `{0}' of method `{1}' must match the constraints for type parameter `{2}' of interface method `{3}'. Consider using an explicit interface implementation instead",
  							tp.GetSignatureForError (), GetSignatureForError (), base_tp.GetSignatureForError (), MethodData.implementing.GetSignatureForError ());
  					}
  				}
  			}
  		}
  
  		public override void Accept (StructuralVisitor visitor)
  		{
  			visitor.Visit (this);
  		}
  
  		//
  		// Creates the type
  		//
  		public override bool Define ()
  		{
  			if (!base.Define ())
  				return false;
  
  			if (type_expr.Type.Kind == MemberKind.Void && parameters.IsEmpty && MemberName.Arity == 0 && MemberName.Name == Destructor.MetadataName) {
  				Report.Warning (465, 1, Location,
  					"Introducing `Finalize' method can interfere with destructor invocation. Did you intend to declare a destructor?");
  			}
  
  			if (partialMethodImplementation != null && IsPartialDefinition)
  				MethodBuilder = partialMethodImplementation.MethodBuilder;
  
  			if (Compiler.Settings.StdLib && ReturnType.IsSpecialRuntimeType) {
  				Error1599 (Location, ReturnType, Report);
  				return false;
  			}
  
  			if (CurrentTypeParameters == null) {
  				if (base_method != null) {
  					if (parameters.Count == 1 && ParameterTypes[0].BuiltinType == BuiltinTypeSpec.Type.Object && Name == "Equals")
  						Parent.PartialContainer.Mark_HasEquals ();
  					else if (parameters.IsEmpty && Name == "GetHashCode")
  						Parent.PartialContainer.Mark_HasGetHashCode ();
  				}
  					
  			} else {
  				DefineTypeParameters ();
  			}
  
  			if (block != null && block.IsIterator) {
  				//
  				// Current method is turned into automatically generated
  				// wrapper which creates an instance of iterator
  				//
  				Iterator.CreateIterator (this, Parent.PartialContainer, ModFlags);
  				ModFlags |= Modifiers.DEBUGGER_HIDDEN;
  			}
  
  			if ((ModFlags & Modifiers.STATIC) == 0)
  				return true;
  
  			if (parameters.HasExtensionMethodType) {
  				if (Parent.PartialContainer.IsStatic && !Parent.IsGeneric) {
  					if (!Parent.IsTopLevel)
  						Report.Error (1109, Location, "`{0}': Extension methods cannot be defined in a nested class",
  							GetSignatureForError ());
  
  					PredefinedAttribute pa = Module.PredefinedAttributes.Extension;
  					if (!pa.IsDefined) {
  						Report.Error (1110, Location,
  							"`{0}': Extension methods cannot be declared without a reference to System.Core.dll assembly. Add the assembly reference or remove `this' modifer from the first parameter",
  							GetSignatureForError ());
  					}
  
  					ModFlags |= Modifiers.METHOD_EXTENSION;
  					Parent.PartialContainer.ModFlags |= Modifiers.METHOD_EXTENSION;
  					Spec.DeclaringType.SetExtensionMethodContainer ();
  					Parent.Module.HasExtensionMethod = true;
  				} else {
  					Report.Error (1106, Location, "`{0}': Extension methods must be defined in a non-generic static class",
  						GetSignatureForError ());
  				}
  			}
  
  			//
  			// This is used to track the Entry Point,
  			//
  			var settings = Compiler.Settings;
  			if (settings.NeedsEntryPoint && Name == "Main" && (settings.MainClass == null || settings.MainClass == Parent.TypeBuilder.FullName)) {
  				if (IsEntryPoint ()) {
  					if (Parent.DeclaringAssembly.EntryPoint == null) {
  						if (Parent.IsGeneric || MemberName.IsGeneric) {
  							Report.Warning (402, 4, Location, "`{0}': an entry point cannot be generic or in a generic type",
  								GetSignatureForError ());
  						} else {
  							SetIsUsed ();
  							Parent.DeclaringAssembly.EntryPoint = this;
  						}
  					} else {
  						Error_DuplicateEntryPoint (Parent.DeclaringAssembly.EntryPoint);
  						Error_DuplicateEntryPoint (this);
  					}
  				} else {
  					Report.Warning (28, 4, Location, "`{0}' has the wrong signature to be an entry point",
  						GetSignatureForError ());
  				}
  			}
  
  			return true;
  		}
  
  		//
  		// Emits the code
  		// 
  		public override void Emit ()
  		{
  			try {
  				if (IsPartialDefinition) {
  					//
  					// Use partial method implementation builder for partial method declaration attributes
  					//
  					if (partialMethodImplementation != null) {
  						MethodBuilder = partialMethodImplementation.MethodBuilder;
  					}
  
  					return;
  				}
  				
  				if ((ModFlags & Modifiers.PARTIAL) != 0 && (caching_flags & Flags.PartialDefinitionExists) == 0) {
  					Report.Error (759, Location, "A partial method `{0}' implementation is missing a partial method declaration",
  						GetSignatureForError ());
  				}
  
  				if (CurrentTypeParameters != null) {
  					var ge = type_expr as GenericTypeExpr;
  					if (ge != null)
  						ge.CheckConstraints (this);
  
  					foreach (Parameter p in parameters.FixedParameters) {
  						ge = p.TypeExpression as GenericTypeExpr;
  						if (ge != null)
  							ge.CheckConstraints (this);
  					}
  
  					for (int i = 0; i < CurrentTypeParameters.Length; ++i) {
  						var tp = CurrentTypeParameters [i];
  						tp.CheckGenericConstraints ();
  						tp.Emit ();
  					}
  				}
  
  				base.Emit ();
  				
  				if ((ModFlags & Modifiers.METHOD_EXTENSION) != 0)
  					Module.PredefinedAttributes.Extension.EmitAttribute (MethodBuilder);
  			} catch {
  				Console.WriteLine ("Internal compiler error at {0}: exception caught while emitting {1}",
  						   Location, MethodBuilder);
  				throw;
  			}
  		}
  
  		public override bool EnableOverloadChecks (MemberCore overload)
  		{
  			// TODO: It can be deleted when members will be defined in correct order
  			if (overload is Operator)
  				return overload.EnableOverloadChecks (this);
  
  			if (overload is Indexer)
  				return false;
  
  			return base.EnableOverloadChecks (overload);
  		}
  
  		public static void Error1599 (Location loc, TypeSpec t, Report Report)
  		{
  			Report.Error (1599, loc, "Method or delegate cannot return type `{0}'", TypeManager.CSharpName (t));
  		}
  
  		protected override bool ResolveMemberType ()
  		{
  			if (GenericMethod != null) {
  				MethodBuilder = Parent.TypeBuilder.DefineMethod (GetFullName (MemberName), flags);
  				if (!GenericMethod.Define (this))
  					return false;
  			}
  
  			return base.ResolveMemberType ();
  		}
  
  		public void SetPartialDefinition (Method methodDefinition)
  		{
  			caching_flags |= Flags.PartialDefinitionExists;
  			methodDefinition.partialMethodImplementation = this;
  
  			// Ensure we are always using method declaration parameters
  			for (int i = 0; i < methodDefinition.parameters.Count; ++i ) {
  				parameters [i].Name = methodDefinition.parameters [i].Name;
  				parameters [i].DefaultValue = methodDefinition.parameters [i].DefaultValue;
  			}
  
  			if (methodDefinition.attributes == null)
  				return;
  
  			if (attributes == null) {
  				attributes = methodDefinition.attributes;
  			} else {
  				attributes.Attrs.AddRange (methodDefinition.attributes.Attrs);
  			}
  		}
  	}
  
  	public abstract class ConstructorInitializer : ExpressionStatement
  	{
  		Arguments argument_list;
  		MethodSpec base_ctor;
  
  		public ConstructorInitializer (Arguments argument_list, Location loc)
  		{
  			this.argument_list = argument_list;
  			this.loc = loc;
  		}
  
  		public Arguments Arguments {
  			get {
  				return argument_list;
  			}
  		}
  
  		public override Expression CreateExpressionTree (ResolveContext ec)
  		{
  			throw new NotSupportedException ("ET");
  		}
  
  		protected override Expression DoResolve (ResolveContext ec)
  		{
  			eclass = ExprClass.Value;
  
  			// FIXME: Hack
  			var caller_builder = (Constructor) ec.MemberContext;
  
  			//
  			// Spec mandates that constructor initializer will not have `this' access
  			//
  			using (ec.Set (ResolveContext.Options.BaseInitializer)) {
  				if (argument_list != null) {
  					bool dynamic;
  					argument_list.Resolve (ec, out dynamic);
  
  					if (dynamic) {
  						ec.Report.Error (1975, loc,
  							"The constructor call cannot be dynamically dispatched within constructor initializer");
  
  						return null;
  					}
  				}
  
  				type = ec.CurrentType;
  				if (this is ConstructorBaseInitializer) {
  					if (ec.CurrentType.BaseType == null)
  						return this;
  
  					type = ec.CurrentType.BaseType;
  					if (ec.CurrentType.IsStruct) {
  						ec.Report.Error (522, loc,
  							"`{0}': Struct constructors cannot call base constructors", caller_builder.GetSignatureForError ());
  						return this;
  					}
  				} else {
  					//
  					// It is legal to have "this" initializers that take no arguments
  					// in structs, they are just no-ops.
  					//
  					// struct D { public D (int a) : this () {}
  					//
  					if (ec.CurrentType.IsStruct && argument_list == null)
  						return this;
  				}
  
  				base_ctor = ConstructorLookup (ec, type, ref argument_list, loc);
  			}
  	
  			// TODO MemberCache: Does it work for inflated types ?
  			if (base_ctor == caller_builder.Spec){
  				ec.Report.Error (516, loc, "Constructor `{0}' cannot call itself",
  					caller_builder.GetSignatureForError ());
  			}
  						
  			return this;
  		}
  
  		public override void Emit (EmitContext ec)
  		{
  			// It can be null for static initializers
  			if (base_ctor == null)
  				return;
  			
  			ec.Mark (loc);
  
  			Invocation.EmitCall (ec, new CompilerGeneratedThis (type, loc), base_ctor, argument_list, loc);
  		}
  
  		public override void EmitStatement (EmitContext ec)
  		{
  			Emit (ec);
  		}
  	}
  
  	public class ConstructorBaseInitializer : ConstructorInitializer {
  		public ConstructorBaseInitializer (Arguments argument_list, Location l) :
  			base (argument_list, l)
  		{
  		}
  	}
  
  	class GeneratedBaseInitializer: ConstructorBaseInitializer {
  		public GeneratedBaseInitializer (Location loc):
  			base (null, loc)
  		{
  		}
  	}
  
  	public class ConstructorThisInitializer : ConstructorInitializer {
  		public ConstructorThisInitializer (Arguments argument_list, Location l) :
  			base (argument_list, l)
  		{
  		}
  	}
  	
  	public class Constructor : MethodCore, IMethodData {
  		public ConstructorBuilder ConstructorBuilder;
  		public ConstructorInitializer Initializer;
  		SecurityType declarative_security;
  		bool has_compliant_args;
  
  		// <summary>
  		//   Modifiers allowed for a constructor.
  		// </summary>
  		public const Modifiers AllowedModifiers =
  			Modifiers.PUBLIC |
  			Modifiers.PROTECTED |
  			Modifiers.INTERNAL |
  			Modifiers.STATIC |
  			Modifiers.UNSAFE |
  			Modifiers.EXTERN |		
  			Modifiers.PRIVATE;
  
  		static readonly string[] attribute_targets = new string [] { "method" };
  
  		public static readonly string ConstructorName = ".ctor";
  		public static readonly string TypeConstructorName = ".cctor";
  
  		//
  		// The spec claims that static is not permitted, but
  		// my very own code has static constructors.
  		//
  		public Constructor (DeclSpace parent, string name, Modifiers mod, Attributes attrs, ParametersCompiled args,
  				    ConstructorInitializer init, Location loc)
  			: base (parent, null, null, mod, AllowedModifiers,
  				new MemberName (name, loc), attrs, args)
  		{
  			Initializer = init;
  		}
  
  		public bool HasCompliantArgs {
  			get { return has_compliant_args; }
  		}
  
  		public override AttributeTargets AttributeTargets {
  			get { return AttributeTargets.Constructor; }
  		}
  
  		//
  		// Returns true if this is a default constructor
  		//
  		public bool IsDefault ()
  		{
  			if ((ModFlags & Modifiers.STATIC) != 0)
  				return parameters.IsEmpty;
  
  			return parameters.IsEmpty &&
  					(Initializer is ConstructorBaseInitializer) &&
  					(Initializer.Arguments == null);
  		}
  
  		public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
  		{
  			if (a.IsValidSecurityAttribute ()) {
  				a.ExtractSecurityPermissionSet (ctor, ref declarative_security);
  				return;
  			}
  
  			if (a.Type == pa.MethodImpl) {
  				is_external_implementation = a.IsInternalCall ();
  			}
  
  			ConstructorBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), cdata);
  		}
  
  		protected override bool CheckBase ()
  		{
  			if ((ModFlags & Modifiers.STATIC) != 0) {
  				if (!parameters.IsEmpty) {
  					Report.Error (132, Location, "`{0}': The static constructor must be parameterless",
  						GetSignatureForError ());
  					return false;
  				}
  
  				// the rest can be ignored
  				return true;
  			}
  
  			// Check whether arguments were correct.
  			if (!DefineParameters (parameters))
  				return false;
  
  			if ((caching_flags & Flags.MethodOverloadsExist) != 0)
  				Parent.MemberCache.CheckExistingMembersOverloads (this, parameters);
  
  			if (Parent.PartialContainer.Kind == MemberKind.Struct && parameters.IsEmpty) {
  				Report.Error (568, Location, 
  					"Structs cannot contain explicit parameterless constructors");
  				return false;
  			}
  
  			CheckProtectedModifier ();
  			
  			return true;
  		}
  		
  		public override void Accept (StructuralVisitor visitor)
  		{
  			visitor.Visit (this);
  		}
  		
  		//
  		// Creates the ConstructorBuilder
  		//
  		public override bool Define ()
  		{
  			if (ConstructorBuilder != null)
  				return true;
  
  			var ca = MethodAttributes.RTSpecialName | MethodAttributes.SpecialName;
  			
  			if ((ModFlags & Modifiers.STATIC) != 0) {
  				ca |= MethodAttributes.Static | MethodAttributes.Private;
  			} else {
  				ca |= ModifiersExtensions.MethodAttr (ModFlags);
  			}
  
  			if (!CheckAbstractAndExtern (block != null))
  				return false;
  			
  			// Check if arguments were correct.
  			if (!CheckBase ())
  				return false;
  
  			ConstructorBuilder = Parent.TypeBuilder.DefineConstructor (
  				ca, CallingConventions,
  				parameters.GetMetaInfo ());
  
  			spec = new MethodSpec (MemberKind.Constructor, Parent.Definition, this, Compiler.BuiltinTypes.Void, ConstructorBuilder, parameters, ModFlags);
  			
  			Parent.MemberCache.AddMember (spec);
  			
  			// It's here only to report an error
  			if (block != null && block.IsIterator) {
  				member_type = Compiler.BuiltinTypes.Void;
  				Iterator.CreateIterator (this, Parent.PartialContainer, ModFlags);
  			}
  
  			return true;
  		}
  
  		//
  		// Emits the code
  		//
  		public override void Emit ()
  		{
  			if (Parent.PartialContainer.IsComImport) {
  				if (!IsDefault ()) {
  					Report.Error (669, Location, "`{0}': A class with the ComImport attribute cannot have a user-defined constructor",
  						Parent.GetSignatureForError ());
  				}
  
  				// Set as internal implementation and reset block data
  				// to ensure no IL is generated
  				ConstructorBuilder.SetImplementationFlags (MethodImplAttributes.InternalCall);
  				block = null;
  			}
  
  			if ((ModFlags & Modifiers.DEBUGGER_HIDDEN) != 0)
  				Module.PredefinedAttributes.DebuggerHidden.EmitAttribute (ConstructorBuilder);
  
  			if (OptAttributes != null)
  				OptAttributes.Emit ();
  
  			base.Emit ();
  
  			//
  			// If we use a "this (...)" constructor initializer, then
  			// do not emit field initializers, they are initialized in the other constructor
  			//
  			bool emit_field_initializers = ((ModFlags & Modifiers.STATIC) != 0) ||
  				!(Initializer is ConstructorThisInitializer);
  
  			BlockContext bc = new BlockContext (this, block, Compiler.BuiltinTypes.Void);
  			bc.Set (ResolveContext.Options.ConstructorScope);
  
  			if (emit_field_initializers)
  				Parent.PartialContainer.ResolveFieldInitializers (bc);
  
  			if (block != null) {
  				// If this is a non-static `struct' constructor and doesn't have any
  				// initializer, it must initialize all of the struct's fields.
  				if ((Parent.PartialContainer.Kind == MemberKind.Struct) &&
  					((ModFlags & Modifiers.STATIC) == 0) && (Initializer == null))
  					block.AddThisVariable (bc, Parent, Location);
  
  				if (block != null && (ModFlags & Modifiers.STATIC) == 0){
  					if (Parent.PartialContainer.Kind == MemberKind.Class && Initializer == null)
  						Initializer = new GeneratedBaseInitializer (Location);
  
  					if (Initializer != null) {
  						block.AddScopeStatement (new StatementExpression (Initializer));
  					}
  				}
  			}
  
  			parameters.ApplyAttributes (this, ConstructorBuilder);
  
  			SourceMethod source = SourceMethod.Create (Parent, ConstructorBuilder, block);
  
  			if (block != null) {
  				if (block.Resolve (null, bc, this)) {
  					EmitContext ec = new EmitContext (this, ConstructorBuilder.GetILGenerator (), bc.ReturnType);
  					ec.With (EmitContext.Options.ConstructorScope, true);
  
  					if (!ec.HasReturnLabel && bc.HasReturnLabel) {
  						ec.ReturnLabel = bc.ReturnLabel;
  						ec.HasReturnLabel = true;
  					}
  
  					block.Emit (ec);
  				}
  			}
  
  			if (source != null)
  				source.CloseMethod ();
  
  			if (declarative_security != null) {
  				foreach (var de in declarative_security) {
  #if STATIC
  					ConstructorBuilder.__AddDeclarativeSecurity (de);
  #else
  					ConstructorBuilder.AddDeclarativeSecurity (de.Key, de.Value);
  #endif
  				}
  			}
  
  			block = null;
  		}
  
  		protected override MemberSpec FindBaseMember (out MemberSpec bestCandidate)
  		{
  			// Is never override
  			bestCandidate = null;
  			return null;
  		}
  
  		public override string GetSignatureForDocumentation ()
  		{
  			return Parent.GetSignatureForDocumentation () + ".#ctor" + parameters.GetSignatureForDocumentation ();
  		}
  
  		public override string GetSignatureForError()
  		{
  			return base.GetSignatureForError () + parameters.GetSignatureForError ();
  		}
  
  		public override string[] ValidAttributeTargets {
  			get {
  				return attribute_targets;
  			}
  		}
  
  		protected override bool VerifyClsCompliance ()
  		{
  			if (!base.VerifyClsCompliance () || !IsExposedFromAssembly ()) {
  				return false;
  			}
  
  			if (!parameters.IsEmpty && Parent.Definition.IsAttribute) {
  				foreach (TypeSpec param in parameters.Types) {
  					if (param.IsArray) {
  						return true;
  					}
  				}
  			}
  
  			has_compliant_args = true;
  			return true;
  		}
  
  		#region IMethodData Members
  
  		public MemberName MethodName {
  			get {
  				return MemberName;
  			}
  		}
  
  		public TypeSpec ReturnType {
  			get {
  				return MemberType;
  			}
  		}
  
  		public EmitContext CreateEmitContext (ILGenerator ig)
  		{
  			throw new NotImplementedException ();
  		}
  
  		public bool IsExcluded()
  		{
  			return false;
  		}
  
  		GenericMethod IMethodData.GenericMethod {
  			get {
  				return null;
  			}
  		}
  
  		void IMethodData.EmitExtraSymbolInfo (SourceMethod source)
  		{ }
  
  		#endregion
  	}
  
  	/// <summary>
  	/// Interface for MethodData class. Holds links to parent members to avoid member duplication.
  	/// </summary>
  	public interface IMethodData : IMemberContext
  	{
  		CallingConventions CallingConventions { get; }
  		Location Location { get; }
  		MemberName MethodName { get; }
  		TypeSpec ReturnType { get; }
  		GenericMethod GenericMethod { get; }
  		ParametersCompiled ParameterInfo { get; }
  		MethodSpec Spec { get; }
  
  		Attributes OptAttributes { get; }
  		ToplevelBlock Block { get; set; }
  
  		EmitContext CreateEmitContext (ILGenerator ig);
  		void EmitExtraSymbolInfo (SourceMethod source);
  	}
  
  	//
  	// Encapsulates most of the Method's state
  	//
  	public class MethodData
  	{
  #if !STATIC
  		static FieldInfo methodbuilder_attrs_field;
  #endif
  
  		public readonly IMethodData method;
  
  		public readonly GenericMethod GenericMethod;
  
  		//
  		// Are we implementing an interface ?
  		//
  		public MethodSpec implementing;
  
  		//
  		// Protected data.
  		//
  		protected InterfaceMemberBase member;
  		protected Modifiers modifiers;
  		protected MethodAttributes flags;
  		protected TypeSpec declaring_type;
  		protected MethodSpec parent_method;
  
  		MethodBuilder builder;
  		public MethodBuilder MethodBuilder {
  			get {
  				return builder;
  			}
  		}
  
  		public TypeSpec DeclaringType {
  			get {
  				return declaring_type;
  			}
  		}
  
  		public MethodData (InterfaceMemberBase member,
  				   Modifiers modifiers, MethodAttributes flags, IMethodData method)
  		{
  			this.member = member;
  			this.modifiers = modifiers;
  			this.flags = flags;
  
  			this.method = method;
  		}
  
  		public MethodData (InterfaceMemberBase member,
  				   Modifiers modifiers, MethodAttributes flags, 
  				   IMethodData method, MethodBuilder builder,
  				   GenericMethod generic, MethodSpec parent_method)
  			: this (member, modifiers, flags, method)
  		{
  			this.builder = builder;
  			this.GenericMethod = generic;
  			this.parent_method = parent_method;
  		}
  
  		public bool Define (DeclSpace parent, string method_full_name, Report Report)
  		{
  			TypeContainer container = parent.PartialContainer;
  
  			PendingImplementation pending = container.PendingImplementations;
  			if (pending != null){
  				implementing = pending.IsInterfaceMethod (method.MethodName, member.InterfaceType, this);
  
  				if (member.InterfaceType != null){
  					if (implementing == null){
  						if (member is PropertyBase) {
  							Report.Error (550, method.Location, "`{0}' is an accessor not found in interface member `{1}{2}'",
  								      method.GetSignatureForError (), TypeManager.CSharpName (member.InterfaceType),
  								      member.GetSignatureForError ().Substring (member.GetSignatureForError ().LastIndexOf ('.')));
  
  						} else {
  							Report.Error (539, method.Location,
  								      "`{0}.{1}' in explicit interface declaration is not a member of interface",
  								      TypeManager.CSharpName (member.InterfaceType), member.ShortName);
  						}
  						return false;
  					}
  					if (implementing.IsAccessor && !(method is AbstractPropertyEventMethod)) {
  						Report.SymbolRelatedToPreviousError (implementing);
  						Report.Error (683, method.Location, "`{0}' explicit method implementation cannot implement `{1}' because it is an accessor",
  							member.GetSignatureForError (), TypeManager.CSharpSignature (implementing));
  						return false;
  					}
  				} else {
  					if (implementing != null) {
  						AbstractPropertyEventMethod prop_method = method as AbstractPropertyEventMethod;
  						if (prop_method == null) {
  							if (implementing.IsAccessor) {
  								Report.SymbolRelatedToPreviousError (implementing);
  								Report.Error (470, method.Location, "Method `{0}' cannot implement interface accessor `{1}'",
  									method.GetSignatureForError (), TypeManager.CSharpSignature (implementing));
  							}
  						} else if (implementing.DeclaringType.IsInterface) {
  							if (!implementing.IsAccessor) {
  								Report.SymbolRelatedToPreviousError (implementing);
  								Report.Error (686, method.Location, "Accessor `{0}' cannot implement interface member `{1}' for type `{2}'. Use an explicit interface implementation",
  									method.GetSignatureForError (), TypeManager.CSharpSignature (implementing), container.GetSignatureForError ());
  							} else {
  								PropertyBase.PropertyMethod pm = prop_method as PropertyBase.PropertyMethod;
  								if (pm != null && pm.HasCustomAccessModifier && (pm.ModFlags & Modifiers.PUBLIC) == 0) {
  									Report.SymbolRelatedToPreviousError (implementing);
  									Report.Error (277, method.Location, "Accessor `{0}' must be declared public to implement interface member `{1}'",
  										method.GetSignatureForError (), implementing.GetSignatureForError ());
  								}
  							}
  						}
  					}
  				}
  			}
  
  			//
  			// For implicit implementations, make sure we are public, for
  			// explicit implementations, make sure we are private.
  			//
  			if (implementing != null){
  				//
  				// Setting null inside this block will trigger a more
  				// verbose error reporting for missing interface implementations
  				//
  				// The "candidate" function has been flagged already
  				// but it wont get cleared
  				//
  				if (member.IsExplicitImpl){
  					if (method.ParameterInfo.HasParams && !implementing.Parameters.HasParams) {
  						Report.SymbolRelatedToPreviousError (implementing);
  						Report.Error (466, method.Location, "`{0}': the explicit interface implementation cannot introduce the params modifier",
  							method.GetSignatureForError ());
  					}
  				} else {
  					if (implementing.DeclaringType.IsInterface) {
  						//
  						// If this is an interface method implementation,
  						// check for public accessibility
  						//
  						if ((flags & MethodAttributes.MemberAccessMask) != MethodAttributes.Public)
  						{
  							implementing = null;
  						}
  					} else if ((flags & MethodAttributes.MemberAccessMask) == MethodAttributes.Private){
  						// We may never be private.
  						implementing = null;
  
  					} else if ((modifiers & Modifiers.OVERRIDE) == 0){
  						//
  						// We may be protected if we're overriding something.
  						//
  						implementing = null;
  					}
  				}
  					
  				//
  				// Static is not allowed
  				//
  				if ((modifiers & Modifiers.STATIC) != 0){
  					implementing = null;
  				}
  			}
  			
  			//
  			// If implementing is still valid, set flags
  			//
  			if (implementing != null){
  				//
  				// When implementing interface methods, set NewSlot
  				// unless, we are overwriting a method.
  				//
  				if (implementing.DeclaringType.IsInterface){
  					if ((modifiers & Modifiers.OVERRIDE) == 0)
  						flags |= MethodAttributes.NewSlot;
  				}
  
  				flags |= MethodAttributes.Virtual | MethodAttributes.HideBySig;
  
  				// Set Final unless we're virtual, abstract or already overriding a method.
  				if ((modifiers & (Modifiers.VIRTUAL | Modifiers.ABSTRACT | Modifiers.OVERRIDE)) == 0)
  					flags |= MethodAttributes.Final;
  
  				//
  				// clear the pending implementation flag (requires explicit methods to be defined first)
  				//
  				parent.PartialContainer.PendingImplementations.ImplementMethod (method.MethodName,
  					member.InterfaceType, this, member.IsExplicitImpl);
  
  				//
  				// Update indexer accessor name to match implementing abstract accessor
  				//
  				if (!implementing.DeclaringType.IsInterface && !member.IsExplicitImpl && implementing.IsAccessor)
  					method_full_name = implementing.MemberDefinition.Name;
  			}
  
  			DefineMethodBuilder (container, method_full_name, method.ParameterInfo);
  
  			if (builder == null)
  				return false;
  
  //			if (container.CurrentType != null)
  //				declaring_type = container.CurrentType;
  //			else
  				declaring_type = container.Definition;
  
  			if (implementing != null && member.IsExplicitImpl) {
  				container.TypeBuilder.DefineMethodOverride (builder, (MethodInfo) implementing.GetMetaInfo ());
  			}
  
  			return true;
  		}
  
  
  		/// <summary>
  		/// Create the MethodBuilder for the method 
  		/// </summary>
  		void DefineMethodBuilder (TypeContainer container, string method_name, ParametersCompiled param)
  		{
  			var return_type = method.ReturnType.GetMetaInfo ();
  			var p_types = param.GetMetaInfo ();
  
  			if (builder == null) {
  				builder = container.TypeBuilder.DefineMethod (
  					method_name, flags, method.CallingConventions,
  					return_type, p_types);
  				return;
  			}
  
  			//
  			// Generic method has been already defined to resolve method parameters
  			// correctly when they use type parameters
  			//
  			builder.SetParameters (p_types);
  			builder.SetReturnType (return_type);
  			if (builder.Attributes != flags) {
  #if STATIC
  				builder.__SetAttributes (flags);
  #else
  				try {
  					if (methodbuilder_attrs_field == null)
  						methodbuilder_attrs_field = typeof (MethodBuilder).GetField ("attrs", BindingFlags.NonPublic | BindingFlags.Instance);
  					methodbuilder_attrs_field.SetValue (builder, flags);
  				} catch {
  					container.Compiler.Report.RuntimeMissingSupport (method.Location, "Generic method MethodAttributes");
  				}
  #endif
  			}
  		}
  
  		//
  		// Emits the code
  		// 
  		public void Emit (DeclSpace parent)
  		{
  			if (GenericMethod != null)
  				GenericMethod.EmitAttributes ();
  
  			var mc = (IMemberContext) method;
  
  			method.ParameterInfo.ApplyAttributes (mc, MethodBuilder);
  
  			SourceMethod source = SourceMethod.Create (parent, MethodBuilder, method.Block);
  
  			ToplevelBlock block = method.Block;
  			if (block != null) {
  				BlockContext bc = new BlockContext (mc, block, method.ReturnType);
  				if (block.Resolve (null, bc, method)) {
  					EmitContext ec = method.CreateEmitContext (MethodBuilder.GetILGenerator ());
  					if (!ec.HasReturnLabel && bc.HasReturnLabel) {
  						ec.ReturnLabel = bc.ReturnLabel;
  						ec.HasReturnLabel = true;
  					}
  
  					block.Emit (ec);
  				}
  			}
  
  			if (source != null) {
  				method.EmitExtraSymbolInfo (source);
  				source.CloseMethod ();
  			}
  		}
  	}
  
  	public class Destructor : MethodOrOperator
  	{
  		const Modifiers AllowedModifiers =
  			Modifiers.UNSAFE |
  			Modifiers.EXTERN;
  
  		static readonly string[] attribute_targets = new string [] { "method" };
  
  		public static readonly string MetadataName = "Finalize";
  
  		public Destructor (DeclSpace parent, Modifiers mod, ParametersCompiled parameters, Attributes attrs, Location l)
  			: base (parent, null, null, mod, AllowedModifiers,
  				new MemberName (MetadataName, l), attrs, parameters)
  		{
  			ModFlags &= ~Modifiers.PRIVATE;
  			ModFlags |= Modifiers.PROTECTED | Modifiers.OVERRIDE;
  		}
  
  		public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
  		{
  			if (a.Type == pa.Conditional) {
  				Error_ConditionalAttributeIsNotValid ();
  				return;
  			}
  
  			base.ApplyAttributeBuilder (a, ctor, cdata, pa);
  		}
  		public override void Accept (StructuralVisitor visitor)
  		{
  			visitor.Visit (this);
  		}
  		
  		protected override bool CheckBase ()
  		{
  			// Don't check base, destructors have special syntax
  			return true;
  		}
  
  		public override void Emit()
  		{
  			var base_type = Parent.PartialContainer.BaseType;
  			if (base_type != null && Block != null) {
  				var base_dtor = MemberCache.FindMember (base_type,
  					new MemberFilter (MetadataName, 0, MemberKind.Destructor, null, null), BindingRestriction.InstanceOnly) as MethodSpec;
  
  				if (base_dtor == null)
  					throw new NotImplementedException ();
  
  				MethodGroupExpr method_expr = MethodGroupExpr.CreatePredefined (base_dtor, base_type, Location);
  				method_expr.InstanceExpression = new BaseThis (base_type, Location);
  
  				var try_block = new ExplicitBlock (block, block.StartLocation, block.EndLocation);
  				var finaly_block = new ExplicitBlock (block, Location, Location);
  
  				//
  				// 0-size arguments to avoid CS0250 error
  				// TODO: Should use AddScopeStatement or something else which emits correct
  				// debugger scope
  				//
  				finaly_block.AddStatement (new StatementExpression (new Invocation (method_expr, new Arguments (0))));
  
  				var tf = new TryFinally (try_block, finaly_block, Location);
  				block.WrapIntoDestructor (tf, try_block);
  			}
  
  			base.Emit ();
  		}
  
  		public override string GetSignatureForError ()
  		{
  			return Parent.GetSignatureForError () + ".~" + Parent.MemberName.Name + "()";
  		}
  
  		protected override bool ResolveMemberType ()
  		{
  			member_type = Compiler.BuiltinTypes.Void;
  			return true;
  		}
  
  		public override string[] ValidAttributeTargets {
  			get {
  				return attribute_targets;
  			}
  		}
  	}
  
  	// Ooouh Martin, templates are missing here.
  	// When it will be possible move here a lot of child code and template method type.
  	public abstract class AbstractPropertyEventMethod : MemberCore, IMethodData {
  		protected MethodData method_data;
  		protected ToplevelBlock block;
  		protected SecurityType declarative_security;
  
  		protected readonly string prefix;
  
  		ReturnParameter return_attributes;
  
  		public AbstractPropertyEventMethod (InterfaceMemberBase member, string prefix, Attributes attrs, Location loc)
  			: base (member.Parent, SetupName (prefix, member, loc), attrs)
  		{
  			this.prefix = prefix;
  		}
  
  		static MemberName SetupName (string prefix, InterfaceMemberBase member, Location loc)
  		{
  			return new MemberName (member.MemberName.Left, prefix + member.ShortName, loc);
  		}
  
  		public void UpdateName (InterfaceMemberBase member)
  		{
  			SetMemberName (SetupName (prefix, member, Location));
  		}
  
  		#region IMethodData Members
  
  		public ToplevelBlock Block {
  			get {
  				return block;
  			}
  
  			set {
  				block = value;
  			}
  		}
  
  		public CallingConventions CallingConventions {
  			get {
  				return CallingConventions.Standard;
  			}
  		}
  
  		public EmitContext CreateEmitContext (ILGenerator ig)
  		{
  			return new EmitContext (this, ig, ReturnType);
  		}
  
  		public bool IsExcluded ()
  		{
  			return false;
  		}
  
  		GenericMethod IMethodData.GenericMethod {
  			get {
  				return null;
  			}
  		}
  
  		public MemberName MethodName {
  			get {
  				return MemberName;
  			}
  		}
  
  		public TypeSpec[] ParameterTypes { 
  			get {
  				return ParameterInfo.Types;
  			}
  		}
  
  		public abstract ParametersCompiled ParameterInfo { get ; }
  		public abstract TypeSpec ReturnType { get; }
  
  		#endregion
  
  		public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
  		{
  			if (a.Type == pa.CLSCompliant || a.Type == pa.Obsolete || a.Type == pa.Conditional) {
  				Report.Error (1667, a.Location,
  					"Attribute `{0}' is not valid on property or event accessors. It is valid on `{1}' declarations only",
  					TypeManager.CSharpName (a.Type), a.GetValidTargets ());
  				return;
  			}
  
  			if (a.IsValidSecurityAttribute ()) {
  
gt: 				a.ExtractSecurityPermissionSet (ctor, ref declarative_security);