2008-06-11 Marek Safar <marek.safar@gmail.com>
[mono.git] / mcs / mcs / ecore.cs
index 16ce07bf83888b4c8a730e39cfd8658d0e5196a6..9470b01ac6fc4efaa1107081a56d21971bbb060b 100644 (file)
@@ -5,7 +5,8 @@
 //   Miguel de Icaza (miguel@ximian.com)
 //   Marek Safar (marek.safar@seznam.cz)
 //
-// (C) 2001, 2002, 2003 Ximian, Inc.
+// Copyright 2001, 2002, 2003 Ximian, Inc.
+// Copyright 2003-2008 Novell, Inc.
 //
 //
 
@@ -96,15 +97,10 @@ namespace Mono.CSharp {
                void AddressOf (EmitContext ec, AddressOp mode);
        }
 
-       /// <summary>
-       ///   This interface is implemented by variables
-       /// </summary>
+       // TODO: Rename to something meaningful, this is flow-analysis interface only
        public interface IVariable {
-               VariableInfo VariableInfo {
-                       get;
-               }
-
-               bool VerifyFixed ();
+               VariableInfo VariableInfo { get; }
+               bool IsFixed { get; }
        }
 
        /// <remarks>
@@ -165,8 +161,7 @@ namespace Mono.CSharp {
                                return TypeManager.IsPrivateAccessible (invocation_type, mi.DeclaringType) ||
                                        TypeManager.IsNestedChildOf (invocation_type, mi.DeclaringType);
 
-                       if (mi.DeclaringType.Assembly == invocation_type.Assembly ||
-                                       TypeManager.IsFriendAssembly (mi.DeclaringType.Assembly)) {
+                       if (TypeManager.IsThisOrFriendAssembly (mi.DeclaringType.Assembly)) {
                                if (ma == MethodAttributes.Assembly || ma == MethodAttributes.FamORAssem)
                                        return true;
                        } else {
@@ -229,8 +224,16 @@ namespace Mono.CSharp {
                // This is used if the expression should be resolved as a type or namespace name.
                // the default implementation fails.   
                //
-               public virtual FullNamedExpression ResolveAsTypeStep (IResolveContext ec,  bool silent)
+               public virtual FullNamedExpression ResolveAsTypeStep (IResolveContext rc,  bool silent)
                {
+                       if (!silent) {
+                               Expression e = this;
+                               EmitContext ec = rc as EmitContext;
+                               if (ec != null)
+                                       e = e.Resolve (ec);
+                               if (e != null)
+                                       e.Error_UnexpectedKind (ResolveFlags.Type, loc);
+                       }
                        return null;
                }
 
@@ -377,7 +380,7 @@ namespace Mono.CSharp {
                        if (b ||
                            Convert.ExplicitReferenceConversionExists (Type, target) ||
                            Convert.ExplicitUnsafe (e, target) != null ||
-                           (ec != null && Convert.UserDefinedConversion (ec, this, target, Location.Null, true) != null))
+                           (ec != null && Convert.ExplicitUserConversion (ec, this, target, Location.Null) != null))
                        {
                                Report.Error (266, loc, "Cannot implicitly convert type `{0}' to `{1}'. " +
                                              "An explicit conversion exists (are you missing a cast?)",
@@ -385,12 +388,6 @@ namespace Mono.CSharp {
                                return;
                        }
 
-                       if (Type != TypeManager.string_type && this is Constant && !(this is EmptyConstantCast)) {
-                               Report.Error (31, loc, "Constant value `{0}' cannot be converted to a `{1}'",
-                                       ((Constant)(this)).GetValue ().ToString (), TypeManager.CSharpName (target));
-                               return;
-                       }
-
                        Report.Error (29, loc, "Cannot implicitly convert type `{0}' to `{1}'",
                                TypeManager.CSharpName (type),
                                TypeManager.CSharpName (target));
@@ -577,12 +574,25 @@ namespace Mono.CSharp {
                /// </remarks>
                public abstract void Emit (EmitContext ec);
 
+               // Emit code to branch to @target if this expression is equivalent to @on_true.
+               // The default implementation is to emit the value, and then emit a brtrue or brfalse.
+               // Subclasses can provide more efficient implementations, but those MUST be equivalent,
+               // including the use of conditional branches.  Note also that a branch MUST be emitted
                public virtual void EmitBranchable (EmitContext ec, Label target, bool on_true)
                {
                        Emit (ec);
                        ec.ig.Emit (on_true ? OpCodes.Brtrue : OpCodes.Brfalse, target);
                }
 
+               // Emit this expression for its side effects, not for its value.
+               // The default implementation is to emit the value, and then throw it away.
+               // Subclasses can provide more efficient implementations, but those MUST be equivalent
+               public virtual void EmitSideEffect (EmitContext ec)
+               {
+                       Emit (ec);
+                       ec.ig.Emit (OpCodes.Pop);
+               }
+
                /// <summary>
                ///   Protected constructor.  Only derivate types should
                ///   be able to be created
@@ -893,6 +903,11 @@ namespace Mono.CSharp {
                        throw new NotImplementedException ();
                }
 
+               protected void Error_PointerInsideExpressionTree ()
+               {
+                       Report.Error (1944, loc, "An expression tree cannot contain an unsafe pointer operation");
+               }
+
                /// <summary>
                ///   Returns an expression that can be used to invoke operator true
                ///   on the expression if it exists.
@@ -914,7 +929,8 @@ namespace Mono.CSharp {
                static Expression GetOperatorTrueOrFalse (EmitContext ec, Expression e, bool is_true, Location loc)
                {
                        MethodGroupExpr operator_group;
-                       operator_group = MethodLookup (ec.ContainerType, e.Type, is_true ? "op_True" : "op_False", loc) as MethodGroupExpr;
+                       string mname = Operator.GetMetadataName (is_true ? Operator.OpType.True : Operator.OpType.False);
+                       operator_group = MethodLookup (ec.ContainerType, e.Type, mname, loc) as MethodGroupExpr;
                        if (operator_group == null)
                                return null;
 
@@ -1078,7 +1094,7 @@ namespace Mono.CSharp {
                                if (t == TypeManager.enum_type)
                                        ig.Emit (OpCodes.Ldind_Ref);
                                else
-                                       LoadFromPtr (ig, TypeManager.EnumToUnderlying (t));
+                                       LoadFromPtr (ig, TypeManager.GetEnumUnderlyingType (t));
                        } else if (t.IsValueType || TypeManager.IsGenericParameter (t))
                                ig.Emit (OpCodes.Ldobj, t);
                        else if (t.IsPointer)
@@ -1093,7 +1109,7 @@ namespace Mono.CSharp {
                public static void StoreFromPtr (ILGenerator ig, Type type)
                {
                        if (TypeManager.IsEnumType (type))
-                               type = TypeManager.EnumToUnderlying (type);
+                               type = TypeManager.GetEnumUnderlyingType (type);
                        if (type == TypeManager.int32_type || type == TypeManager.uint32_type)
                                ig.Emit (OpCodes.Stind_I4);
                        else if (type == TypeManager.int64_type || type == TypeManager.uint64_type)
@@ -1230,11 +1246,10 @@ namespace Mono.CSharp {
                        return cloned;
                }
 
-               public virtual Expression CreateExpressionTree (EmitContext ec)
-               {
-                       throw new NotImplementedException (
-                               "Expression tree conversion not implemented for " + GetType ());
-               }
+               //
+               // Implementation of expression to expression tree conversion
+               //
+               public abstract Expression CreateExpressionTree (EmitContext ec);
 
                protected Expression CreateExpressionFactoryCall (string name, ArrayList args)
                {
@@ -1248,8 +1263,21 @@ namespace Mono.CSharp {
 
                public static Expression CreateExpressionFactoryCall (string name, TypeArguments typeArguments, ArrayList args, Location loc)
                {
-                       TypeExpression texpr = new TypeExpression (LinqExpression.expression_type, loc);
-                       return new Invocation (new MemberAccess (texpr, name, typeArguments, loc), args);
+                       return new Invocation (new MemberAccess (CreateExpressionTypeExpression (loc), name, typeArguments, loc), args);
+               }
+
+               protected static TypeExpr CreateExpressionTypeExpression (Location loc)
+               {
+                       TypeExpr texpr = TypeManager.expression_type_expr;
+                       if (texpr == null) {
+                               Type t = TypeManager.CoreLookupType ("System.Linq.Expressions", "Expression", Kind.Class, true);
+                               if (t == null)
+                                       return null;
+
+                               TypeManager.expression_type_expr = texpr = new TypeExpression (t, Location.Null);
+                       }
+
+                       return texpr;
                }
        }
 
@@ -1282,6 +1310,11 @@ namespace Mono.CSharp {
                ///   Emit that will always leave a value on the stack).
                /// </summary>
                public abstract void EmitStatement (EmitContext ec);
+
+               public override void EmitSideEffect (EmitContext ec)
+               {
+                       EmitStatement (ec);
+               }
        }
 
        /// <summary>
@@ -1296,32 +1329,27 @@ namespace Mono.CSharp {
        ///   would be "unsigned int".
        ///
        /// </summary>
-       public class EmptyCast : Expression
+       public abstract class TypeCast : Expression
        {
                protected Expression child;
 
-               protected EmptyCast (Expression child, Type return_type)
+               protected TypeCast (Expression child, Type return_type)
                {
                        eclass = child.eclass;
                        loc = child.Location;
                        type = return_type;
                        this.child = child;
                }
-               
-               public static Expression Create (Expression child, Type type)
-               {
-                       Constant c = child as Constant;
-                       if (c != null)
-                               return new EmptyConstantCast (c, type);
-
-                       return new EmptyCast (child, type);
-               }
 
                public override Expression CreateExpressionTree (EmitContext ec)
                {
                        ArrayList args = new ArrayList (2);
                        args.Add (new Argument (child.CreateExpressionTree (ec)));
                        args.Add (new Argument (new TypeOf (new TypeExpression (type, loc), loc)));
+
+                       if (type.IsPointer || child.Type.IsPointer)
+                               Error_PointerInsideExpressionTree ();
+
                        return CreateExpressionFactoryCall (ec.CheckState ? "ConvertChecked" : "Convert", args);
                }
 
@@ -1345,16 +1373,50 @@ namespace Mono.CSharp {
 
                protected override void CloneTo (CloneContext clonectx, Expression t)
                {
-                       EmptyCast target = (EmptyCast) t;
+                       TypeCast target = (TypeCast) t;
 
                        target.child = child.Clone (clonectx);
                }
+
+               public override bool IsNull {
+                       get { return child.IsNull; }
+               }
+       }
+
+       public class EmptyCast : TypeCast {
+               EmptyCast (Expression child, Type target_type)
+                       : base (child, target_type)
+               {
+               }
+
+               public static Expression Create (Expression child, Type type)
+               {
+                       Constant c = child as Constant;
+                       if (c != null)
+                               return new EmptyConstantCast (c, type);
+
+                       EmptyCast e = child as EmptyCast;
+                       if (e != null)
+                               return new EmptyCast (e.child, type);
+
+                       return new EmptyCast (child, type);
+               }
+
+               public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
+               {
+                       child.EmitBranchable (ec, label, on_true);
+               }
+
+               public override void EmitSideEffect (EmitContext ec)
+               {
+                       child.EmitSideEffect (ec);
+               }
        }
 
        /// <summary>
        ///    Performs a cast using an operator (op_Explicit or op_Implicit)
        /// </summary>
-       public class OperatorCast : EmptyCast {
+       public class OperatorCast : TypeCast {
                MethodInfo conversion_operator;
                bool find_explicit;
                        
@@ -1385,7 +1447,7 @@ namespace Mono.CSharp {
                        foreach (MethodInfo oper in mi) {
                                ParameterData pd = TypeManager.GetParameterData (oper);
 
-                               if (pd.ParameterType (0) == child.Type && oper.ReturnType == type)
+                               if (pd.ParameterType (0) == child.Type && TypeManager.TypeToCoreType (oper.ReturnType) == type)
                                        return oper;
                        }
 
@@ -1411,7 +1473,7 @@ namespace Mono.CSharp {
        /// <summary>
        ///     This is a numeric cast to a Decimal
        /// </summary>
-       public class CastToDecimal : EmptyCast {
+       public class CastToDecimal : TypeCast {
                MethodInfo conversion_operator;
 
                public CastToDecimal (Expression child)
@@ -1440,7 +1502,7 @@ namespace Mono.CSharp {
                        foreach (MethodInfo oper in mi) {
                                ParameterData pd = TypeManager.GetParameterData (oper);
 
-                               if (pd.ParameterType (0) == child.Type && oper.ReturnType == type)
+                               if (pd.ParameterType (0) == child.Type && TypeManager.TypeToCoreType (oper.ReturnType) == type)
                                        return oper;
                        }
 
@@ -1458,7 +1520,7 @@ namespace Mono.CSharp {
        /// <summary>
        ///     This is an explicit numeric cast from a Decimal
        /// </summary>
-       public class CastFromDecimal : EmptyCast
+       public class CastFromDecimal : TypeCast
        {
                static IDictionary operators;
 
@@ -1483,7 +1545,7 @@ namespace Mono.CSharp {
                                foreach (MethodInfo oper in all_oper) {
                                        ParameterData pd = TypeManager.GetParameterData (oper);
                                        if (pd.ParameterType (0) == TypeManager.decimal_type)
-                                               operators.Add (oper.ReturnType, oper);
+                                               operators.Add (TypeManager.TypeToCoreType (oper.ReturnType), oper);
                                }
                        }
 
@@ -1533,6 +1595,17 @@ namespace Mono.CSharp {
                        return child.ConvertExplicitly (in_checked_context, target_type);
                }
 
+               public override Expression CreateExpressionTree (EmitContext ec)
+               {
+                       ArrayList args = new ArrayList (2);
+                       args.Add (new Argument (child.CreateExpressionTree (ec)));
+                       args.Add (new Argument (new TypeOf (new TypeExpression (type, loc), loc)));
+                       if (type.IsPointer)
+                               Error_PointerInsideExpressionTree ();
+
+                       return CreateExpressionFactoryCall ("Convert", args);
+               }
+
                public override Constant Increment ()
                {
                        return child.Increment ();
@@ -1552,13 +1625,23 @@ namespace Mono.CSharp {
 
                public override bool IsZeroInteger {
                        get { return child.IsZeroInteger; }
-               }               
+               }
                
                public override void Emit (EmitContext ec)
                {
                        child.Emit (ec);
                }
 
+               public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
+               {
+                       child.EmitBranchable (ec, label, on_true);
+               }
+
+               public override void EmitSideEffect (EmitContext ec)
+               {
+                       child.EmitSideEffect (ec);
+               }
+
                public override Constant ConvertImplicitly (Type target_type)
                {
                        // FIXME: Do we need to check user conversions?
@@ -1596,6 +1679,16 @@ namespace Mono.CSharp {
                        Child.Emit (ec);
                }
 
+               public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
+               {
+                       Child.EmitBranchable (ec, label, on_true);
+               }
+
+               public override void EmitSideEffect (EmitContext ec)
+               {
+                       Child.EmitSideEffect (ec);
+               }
+
                public override bool GetAttributableValue (Type value_type, out object value)
                {
                        value = GetTypedValue ();
@@ -1687,7 +1780,7 @@ namespace Mono.CSharp {
        ///   The effect of it is to box the value type emitted by the previous
        ///   operation.
        /// </summary>
-       public class BoxedCast : EmptyCast {
+       public class BoxedCast : TypeCast {
 
                public BoxedCast (Expression expr, Type target_type)
                        : base (expr, target_type)
@@ -1709,9 +1802,20 @@ namespace Mono.CSharp {
                        
                        ec.ig.Emit (OpCodes.Box, child.Type);
                }
+
+               public override void EmitSideEffect (EmitContext ec)
+               {
+                       // boxing is side-effectful, since it involves runtime checks, except when boxing to Object or ValueType
+                       // so, we need to emit the box+pop instructions in most cases
+                       if (child.Type.IsValueType &&
+                           (type == TypeManager.object_type || type == TypeManager.value_type))
+                               child.EmitSideEffect (ec);
+                       else
+                               base.EmitSideEffect (ec);
+               }
        }
 
-       public class UnboxCast : EmptyCast {
+       public class UnboxCast : TypeCast {
                public UnboxCast (Expression expr, Type return_type)
                        : base (expr, return_type)
                {
@@ -1758,7 +1862,7 @@ namespace Mono.CSharp {
        ///   context, so they should generate the conv.ovf opcodes instead of
        ///   conv opcodes.
        /// </summary>
-       public class ConvCast : EmptyCast {
+       public class ConvCast : TypeCast {
                public enum Mode : byte {
                        I1_U1, I1_U2, I1_U4, I1_U8, I1_CH,
                        U1_I1, U1_CH,
@@ -1966,7 +2070,7 @@ namespace Mono.CSharp {
                }
        }
        
-       public class OpcodeCast : EmptyCast {
+       public class OpcodeCast : TypeCast {
                OpCode op, op2;
                bool second_valid;
                
@@ -1987,12 +2091,6 @@ namespace Mono.CSharp {
                        second_valid = true;
                }
 
-               public override Expression CreateExpressionTree (EmitContext ec)
-               {
-                       // This has no expresion tree representation
-                       return this;
-               }
-
                public override Expression DoResolve (EmitContext ec)
                {
                        // This should never be invoked, we are born in fully
@@ -2019,7 +2117,7 @@ namespace Mono.CSharp {
        ///   This kind of cast is used to encapsulate a child and cast it
        ///   to the class requested
        /// </summary>
-       public class ClassCast : EmptyCast {
+       public class ClassCast : TypeCast {
                public ClassCast (Expression child, Type return_type)
                        : base (child, return_type)
                        
@@ -2049,37 +2147,182 @@ namespace Mono.CSharp {
                                ec.ig.Emit (OpCodes.Castclass, type);
                }
        }
+
+       //
+       // Used when resolved expression has different representations for
+       // expression trees and emit phase
+       //
+       public class ReducedExpression : Expression
+       {
+               class ReducedConstantExpression : Constant
+               {
+                       readonly Constant expr;
+                       readonly Expression orig_expr;
+
+                       public ReducedConstantExpression (Constant expr, Expression orig_expr)
+                               : base (expr.Location)
+                       {
+                               this.expr = expr;
+                               this.orig_expr = orig_expr;
+                               eclass = expr.eclass;
+                               type = expr.Type;
+                       }
+
+                       public override string AsString ()
+                       {
+                               return expr.AsString ();
+                       }
+
+                       public override Expression CreateExpressionTree (EmitContext ec)
+                       {
+                               return orig_expr.CreateExpressionTree (ec);
+                       }
+
+                       public override object GetValue ()
+                       {
+                               return expr.GetValue ();
+                       }
+
+                       public override Constant ConvertExplicitly (bool in_checked_context, Type target_type)
+                       {
+                               throw new NotImplementedException ();
+                       }
+
+                       public override Expression DoResolve (EmitContext ec)
+                       {
+                               return this;
+                       }
+
+                       public override Constant Increment ()
+                       {
+                               throw new NotImplementedException ();
+                       }
+
+                       public override bool IsDefaultValue {
+                               get {
+                                       return expr.IsDefaultValue;
+                               }
+                       }
+
+                       public override bool IsNegative {
+                               get {
+                                       return expr.IsNegative;
+                               }
+                       }
+
+                       public override void Emit (EmitContext ec)
+                       {
+                               expr.Emit (ec);
+                       }
+               }
+
+               readonly Expression expr, orig_expr;
+
+               private ReducedExpression (Expression expr, Expression orig_expr)
+               {
+                       this.expr = expr;
+                       this.orig_expr = orig_expr;
+                       this.loc = orig_expr.Location;
+               }
+
+               public static Expression Create (Constant expr, Expression original_expr)
+               {
+                       return new ReducedConstantExpression (expr, original_expr);
+               }
+
+               public static Expression Create (Expression expr, Expression original_expr)
+               {
+                       Constant c = expr as Constant;
+                       if (c != null)
+                               return Create (c, original_expr);
+
+                       return new ReducedExpression (expr, original_expr);
+               }
+
+               public override Expression CreateExpressionTree (EmitContext ec)
+               {
+                       return orig_expr.CreateExpressionTree (ec);
+               }
+
+               public override Expression DoResolve (EmitContext ec)
+               {
+                       eclass = expr.eclass;
+                       type = expr.Type;
+                       return this;
+               }
+
+               public override void Emit (EmitContext ec)
+               {
+                       expr.Emit (ec);
+               }
+
+               public override void EmitBranchable (EmitContext ec, Label target, bool on_true)
+               {
+                       expr.EmitBranchable (ec, target, on_true);
+               }
+       }
+
+       //
+       // Unresolved type name expressions
+       //
+       public abstract class ATypeNameExpression : FullNamedExpression
+       {
+               public readonly string Name;
+               protected TypeArguments targs;
+
+               protected ATypeNameExpression (string name, Location l)
+               {
+                       Name = name;
+                       loc = l;
+               }
+
+               protected ATypeNameExpression (string name, TypeArguments targs, Location l)
+               {
+                       Name = name;
+                       this.targs = targs;
+                       loc = l;
+               }
+
+               public bool HasTypeArguments {
+                       get {
+                               return targs != null;
+                       }
+               }
+
+               public override string GetSignatureForError ()
+               {
+                       if (targs != null) {
+                               return TypeManager.RemoveGenericArity (Name) + "<" +
+                                       targs.GetSignatureForError () + ">";
+                       }
+
+                       return Name;
+               }
+       }
        
        /// <summary>
        ///   SimpleName expressions are formed of a single word and only happen at the beginning 
        ///   of a dotted-name.
        /// </summary>
-       public class SimpleName : Expression {
-               public readonly string Name;
-               public readonly TypeArguments Arguments;
+       public class SimpleName : ATypeNameExpression {
                bool in_transit;
 
                public SimpleName (string name, Location l)
+                       : base (name, l)
                {
-                       Name = name;
-                       loc = l;
                }
 
                public SimpleName (string name, TypeArguments args, Location l)
+                       : base (name, args, l)
                {
-                       Name = name;
-                       Arguments = args;
-                       loc = l;
                }
 
                public SimpleName (string name, TypeParameter[] type_params, Location l)
+                       : base (name, l)
                {
-                       Name = name;
-                       loc = l;
-
-                       Arguments = new TypeArguments (l);
+                       targs = new TypeArguments (l);
                        foreach (TypeParameter type_param in type_params)
-                               Arguments.Add (new TypeParameterExpr (type_param, l));
+                               targs.Add (new TypeParameterExpr (type_param, l));
                }
 
                public static string RemoveGenericArity (string name)
@@ -2112,7 +2355,7 @@ namespace Mono.CSharp {
 
                public SimpleName GetMethodGroup ()
                {
-                       return new SimpleName (RemoveGenericArity (Name), Arguments, loc);
+                       return new SimpleName (RemoveGenericArity (Name), targs, loc);
                }
 
                public static void Error_ObjectRefRequired (EmitContext ec, Location l, string name)
@@ -2176,7 +2419,7 @@ namespace Mono.CSharp {
 
                        Type[] gen_params = TypeManager.GetTypeArguments (t);
 
-                       int arg_count = Arguments != null ? Arguments.Count : 0;
+                       int arg_count = targs != null ? targs.Count : 0;
 
                        for (; (ds != null) && ds.IsGeneric; ds = ds.Parent) {
                                if (arg_count + ds.CountTypeParameters == gen_params.Length) {
@@ -2184,8 +2427,8 @@ namespace Mono.CSharp {
                                        foreach (TypeParameter param in ds.TypeParameters)
                                                new_args.Add (new TypeParameterExpr (param, loc));
 
-                                       if (Arguments != null)
-                                               new_args.Add (Arguments);
+                                       if (targs != null)
+                                               new_args.Add (targs);
 
                                        return new ConstructedType (t, new_args, loc);
                                }
@@ -2211,8 +2454,8 @@ namespace Mono.CSharp {
                                if (nested != null)
                                        return nested.ResolveAsTypeStep (ec, false);
 
-                               if (Arguments != null) {
-                                       ConstructedType ct = new ConstructedType (fne, Arguments, loc);
+                               if (targs != null) {
+                                       ConstructedType ct = new ConstructedType (fne, targs, loc);
                                        return ct.ResolveAsTypeStep (ec, false);
                                }
 
@@ -2251,7 +2494,7 @@ namespace Mono.CSharp {
                                return;
                        }
 
-                       if (Arguments != null) {
+                       if (targs != null) {
                                FullNamedExpression retval = ec.DeclContainer.LookupNamespaceOrType (SimpleName.RemoveGenericArity (Name), loc, true);
                                if (retval != null) {
                                        Namespace.Error_TypeArgumentsCannotBeUsed (retval.Type, loc);
@@ -2328,7 +2571,7 @@ namespace Mono.CSharp {
                        if (current_block != null){
                                LocalInfo vi = current_block.GetLocalInfo (Name);
                                if (vi != null){
-                                       if (Arguments != null) {
+                                       if (targs != null) {
                                                Report.Error (307, loc,
                                                              "The variable `{0}' cannot be used with type arguments",
                                                              Name);
@@ -2348,7 +2591,7 @@ namespace Mono.CSharp {
 
                                ParameterReference pref = current_block.Toplevel.GetParameterReference (Name, loc);
                                if (pref != null) {
-                                       if (Arguments != null) {
+                                       if (targs != null) {
                                                Report.Error (307, loc,
                                                              "The variable `{0}' cannot be used with type arguments",
                                                              Name);
@@ -2434,11 +2677,11 @@ namespace Mono.CSharp {
                        }
 
                        if (e is TypeExpr) {
-                               if (Arguments == null)
+                               if (targs == null)
                                        return e;
 
                                ConstructedType ct = new ConstructedType (
-                                       (FullNamedExpression) e, Arguments, loc);
+                                       e.Type, targs, loc);
                                return ct.ResolveAsTypeStep (ec, false);
                        }
 
@@ -2476,9 +2719,9 @@ namespace Mono.CSharp {
                                if (me == null)
                                        return null;
 
-                               if (Arguments != null) {
-                                       Arguments.Resolve (ec);
-                                       me.SetTypeArguments (Arguments);
+                               if (targs != null) {
+                                       targs.Resolve (ec);
+                                       me.SetTypeArguments (targs);
                                }
 
                                if (!me.IsStatic && (me.InstanceExpression != null) &&
@@ -2499,26 +2742,6 @@ namespace Mono.CSharp {
                        return e;
                }
                
-               public override void Emit (EmitContext ec)
-               {
-                       throw new InternalErrorException ("The resolve phase was not executed");
-               }
-
-               public override string ToString ()
-               {
-                       return Name;
-               }
-
-               public override string GetSignatureForError ()
-               {
-                       if (Arguments != null) {
-                               return TypeManager.RemoveGenericArity (Name) + "<" +
-                                       Arguments.GetSignatureForError () + ">";
-                       }
-
-                       return Name;
-               }
-
                protected override void CloneTo (CloneContext clonectx, Expression target)
                {
                        // CloneTo: Nothing, we do not keep any state on this expression
@@ -2530,13 +2753,21 @@ namespace Mono.CSharp {
        ///   section 10.8.1 (Fully Qualified Names).
        /// </summary>
        public abstract class FullNamedExpression : Expression {
+
+               public override Expression CreateExpressionTree (EmitContext ec)
+               {
+                       throw new NotSupportedException ("ET");
+               }
+
                public override FullNamedExpression ResolveAsTypeStep (IResolveContext ec, bool silent)
                {
                        return this;
                }
 
-               public abstract string FullName {
-                       get;
+               public override void Emit (EmitContext ec)
+               {
+                       throw new InternalErrorException ("FullNamedExpression `{0}' found in resolved tree",
+                               GetSignatureForError ());
                }
        }
        
@@ -2559,11 +2790,6 @@ namespace Mono.CSharp {
                        return ResolveAsTypeTerminal (ec, false);
                }
 
-               override public void Emit (EmitContext ec)
-               {
-                       throw new Exception ("Should never be called");
-               }
-
                public virtual bool CheckAccessLevel (DeclSpace ds)
                {
                        return ds.CheckAccessLevel (Type);
@@ -2604,10 +2830,6 @@ namespace Mono.CSharp {
 
                protected abstract TypeExpr DoResolveAsTypeStep (IResolveContext ec);
 
-               public abstract string Name {
-                       get;
-               }
-
                public override bool Equals (object obj)
                {
                        TypeExpr tobj = obj as TypeExpr;
@@ -2621,11 +2843,6 @@ namespace Mono.CSharp {
                {
                        return Type.GetHashCode ();
                }
-               
-               public override string ToString ()
-               {
-                       return Name;
-               }
        }
 
        /// <summary>
@@ -2648,14 +2865,6 @@ namespace Mono.CSharp {
                {
                        return this;
                }
-
-               public override string Name {
-                       get { return Type.ToString (); }
-               }
-
-               public override string FullName {
-                       get { return Type.FullName; }
-               }
        }
 
        /// <summary>
@@ -2789,14 +2998,6 @@ namespace Mono.CSharp {
                        return this;
                }
 
-               public override string Name {
-                       get { return name; }
-               }
-
-               public override string FullName {
-                       get { return name; }
-               }
-
                protected override void CloneTo (CloneContext clonectx, Expression target)
                {
                        // CloneTo: Nothing, we do not keep any state on this expression
@@ -2825,6 +3026,11 @@ namespace Mono.CSharp {
                        loc = l;
                }
 
+               protected override void CloneTo (CloneContext clonectx, Expression target)
+               {
+                       // Nothing to clone
+               }
+
                protected override TypeExpr DoResolveAsTypeStep (IResolveContext ec)
                {
                        Expression expr;
@@ -2842,99 +3048,6 @@ namespace Mono.CSharp {
                        type = fne.Type;
                        return new TypeExpression (type, loc);
                }
-
-               public override string Name {
-                       get { return name.FullName; }
-               }
-
-               public override string FullName {
-                       get { return name.FullName; }
-               }
-       }
-
-       public class TypeAliasExpression : TypeExpr {
-               FullNamedExpression alias;
-               TypeExpr texpr;
-               TypeArguments args;
-               string name;
-
-               public TypeAliasExpression (FullNamedExpression alias, TypeArguments args, Location l)
-               {
-                       this.alias = alias;
-                       this.args = args;
-                       loc = l;
-
-                       eclass = ExprClass.Type;
-                       if (args != null)
-                               name = alias.FullName + "<" + args.ToString () + ">";
-                       else
-                               name = alias.FullName;
-               }
-
-               public override string Name {
-                       get { return alias.FullName; }
-               }
-
-               public override string FullName {
-                       get { return name; }
-               }
-
-               protected override TypeExpr DoResolveAsTypeStep (IResolveContext ec)
-               {
-                       texpr = alias.ResolveAsTypeTerminal (ec, false);
-                       if (texpr == null)
-                               return null;
-
-                       Type type = texpr.Type;
-                       int num_args = TypeManager.GetNumberOfTypeArguments (type);
-
-                       if (args != null) {
-                               if (num_args == 0) {
-                                       Report.Error (308, loc,
-                                                     "The non-generic type `{0}' cannot " +
-                                                     "be used with type arguments.",
-                                                     TypeManager.CSharpName (type));
-                                       return null;
-                               }
-
-                               ConstructedType ctype = new ConstructedType (type, args, loc);
-                               return ctype.ResolveAsTypeTerminal (ec, false);
-                       } else if (num_args > 0) {
-                               Report.Error (305, loc,
-                                             "Using the generic type `{0}' " +
-                                             "requires {1} type arguments",
-                                             TypeManager.CSharpName (type), num_args.ToString ());
-                               return null;
-                       }
-
-                       return texpr;
-               }
-
-               public override bool CheckAccessLevel (DeclSpace ds)
-               {
-                       return texpr.CheckAccessLevel (ds);
-               }
-
-               public override bool AsAccessible (DeclSpace ds)
-               {
-                       return texpr.AsAccessible (ds);
-               }
-
-               public override bool IsClass {
-                       get { return texpr.IsClass; }
-               }
-
-               public override bool IsValueType {
-                       get { return texpr.IsValueType; }
-               }
-
-               public override bool IsInterface {
-                       get { return texpr.IsInterface; }
-               }
-
-               public override bool IsSealed {
-                       get { return texpr.IsSealed; }
-               }
        }
 
        /// <summary>
@@ -2993,6 +3106,11 @@ namespace Mono.CSharp {
                                      "with an instance reference, qualify it with a type name instead", name);
                }
 
+               public static void Error_BaseAccessInExpressionTree (Location loc)
+               {
+                       Report.Error (831, loc, "An expression tree may not contain a base access");
+               }
+
                // TODO: possible optimalization
                // Cache resolved constant result in FieldBuilder <-> expression map
                public virtual MemberExpr ResolveMemberAccess (EmitContext ec, Expression left, Location loc,
@@ -3133,7 +3251,7 @@ namespace Mono.CSharp {
                                return null;
 
                        // Search continues
-                       ExtensionMethodGroupExpr e = ns.LookupExtensionMethod (type, null, Name);
+                       ExtensionMethodGroupExpr e = ns.LookupExtensionMethod (type, null, Name, loc);
                        if (e == null)
                                return base.OverloadResolve (ec, ref arguments, false, loc);
 
@@ -3284,8 +3402,11 @@ namespace Mono.CSharp {
                                //
                                if (TypeManager.DropGenericTypeArguments (p) == TypeManager.expression_type) {
                                        p = TypeManager.GetTypeArguments (p) [0];
+                               }
+                               if (TypeManager.DropGenericTypeArguments (q) == TypeManager.expression_type) {
                                        q = TypeManager.GetTypeArguments (q) [0];
                                }
+                               
                                p = Delegate.GetInvokeMethod (null, p).ReturnType;
                                q = Delegate.GetInvokeMethod (null, q).ReturnType;
                        } else {
@@ -3511,8 +3632,20 @@ namespace Mono.CSharp {
 
                public override Expression CreateExpressionTree (EmitContext ec)
                {
-                       return new Cast (new TypeExpression (typeof (MethodInfo), loc),
-                               new TypeOfMethod ((MethodInfo)best_candidate, loc));
+                       if (best_candidate == null) {
+                               Report.Error (1953, loc, "An expression tree cannot contain an expression with method group");
+                               return null;
+                       }
+
+                       if (best_candidate.IsConstructor)
+                               return new TypeOfConstructorInfo (best_candidate, loc);
+
+                       IMethodData md = TypeManager.GetMethod (best_candidate);
+                       if (md != null && md.IsExcluded ())
+                               Report.Error (765, loc,
+                                       "Partial methods with only a defining declaration or removed conditional methods cannot be used in an expression tree");
+                       
+                       return new TypeOfMethodInfo (best_candidate, loc);
                }
                
                override public Expression DoResolve (EmitContext ec)
@@ -3590,6 +3723,12 @@ namespace Mono.CSharp {
                                Report.Error (1503, loc, "Argument {0}: Cannot convert type `{1}' to `{2}'", index, p1, p2);
                        }
                }
+
+               public override void Error_ValueCannotBeConverted (EmitContext ec, Location loc, Type target, bool expl)
+               {
+                       Report.Error (428, loc, "Cannot convert method group `{0}' to non-delegate type `{1}'. Consider using parentheses to invoke the method",
+                               Name, TypeManager.CSharpName (target));
+               }
                
                protected virtual int GetApplicableParametersCount (MethodBase method, ParameterData parameters)
                {
@@ -3724,21 +3863,13 @@ namespace Mono.CSharp {
                                return 0;
                        }
 
-                       // FIXME: Kill this abomination (EmitContext.TempEc)
-                       EmitContext prevec = EmitContext.TempEc;
-                       EmitContext.TempEc = ec;
-                       try {
-                               if (delegate_type != null ?
-                                       !Delegate.IsTypeCovariant (argument.Expr, parameter) :
-                                       !Convert.ImplicitConversionExists (ec, argument.Expr, parameter))
-                                       return 2;
-
-                               if (arg_mod != param_mod)
-                                       return 1;
+                       if (delegate_type != null ?
+                               !Delegate.IsTypeCovariant (argument.Expr, parameter) :
+                               !Convert.ImplicitConversionExists (ec, argument.Expr, parameter))
+                               return 2;
 
-                       } finally {
-                               EmitContext.TempEc = prevec;
-                       }
+                       if (arg_mod != param_mod)
+                               return 1;
 
                        return 0;
                }
@@ -3996,7 +4127,7 @@ namespace Mono.CSharp {
                                // not an extension method. We start extension methods lookup from here
                                //
                                if (InstanceExpression != null) {
-                                       ExtensionMethodGroupExpr ex_method_lookup = ec.TypeContainer.LookupExtensionMethod (type, Name);
+                                       ExtensionMethodGroupExpr ex_method_lookup = ec.TypeContainer.LookupExtensionMethod (type, Name, loc);
                                        if (ex_method_lookup != null) {
                                                ex_method_lookup.ExtensionExpression = InstanceExpression;
                                                ex_method_lookup.SetTypeArguments (type_arguments);
@@ -4150,7 +4281,7 @@ namespace Mono.CSharp {
                        // should be better than all the others
                        //
                        MethodBase ambiguous = null;
-                       for (int ix = 0; ix < candidate_top; ix++) {
+                       for (int ix = 1; ix < candidate_top; ix++) {
                                MethodBase candidate = (MethodBase) candidates [ix];
 
                                if (candidate == best_candidate)
@@ -4301,7 +4432,7 @@ namespace Mono.CSharp {
 
                                        continue;
                                }
-               
+
                                Expression conv;
                                if (TypeManager.IsEqual (a.Type, pt)) {
                                        conv = a.Expr;
@@ -4315,12 +4446,14 @@ namespace Mono.CSharp {
                                // Convert params arguments to an array initializer
                                //
                                if (params_initializers != null) {
-                                       params_initializers.Add (conv);
+                                       // we choose to use 'a.Expr' rather than 'conv' so that
+                                       // we don't hide the kind of expression we have (esp. CompoundAssign.Helper)
+                                       params_initializers.Add (a.Expr);
                                        arguments.RemoveAt (a_idx--);
                                        --arg_count;
                                        continue;
                                }
-                               
+
                                // Update the argument with the implicit conversion
                                a.Expr = conv;
                        }
@@ -4328,7 +4461,7 @@ namespace Mono.CSharp {
                        //
                        // Fill not provided arguments required by params modifier
                        //
-                       if (params_initializers == null && pd.HasParams && arg_count < pd.Count) {
+                       if (params_initializers == null && pd.HasParams && arg_count < pd.Count && a_idx + 1 == pd.Count) {
                                if (arguments == null)
                                        arguments = new ArrayList (1);
 
@@ -4405,6 +4538,11 @@ namespace Mono.CSharp {
                        return base.ResolveMemberAccess (ec, left, loc, original);
                }
 
+               public override Expression CreateExpressionTree (EmitContext ec)
+               {
+                       throw new NotSupportedException ("ET");
+               }
+
                public override Expression DoResolve (EmitContext ec)
                {
                        IConstant ic = TypeManager.GetConstant (constant);
@@ -4500,6 +4638,26 @@ namespace Mono.CSharp {
                        return base.ResolveMemberAccess (ec, left, loc, original);
                }
 
+               public override Expression CreateExpressionTree (EmitContext ec)
+               {
+                       Expression instance;
+                       if (InstanceExpression == null) {
+                               instance = new NullLiteral (loc);
+                       } else {
+                               instance = InstanceExpression.CreateExpressionTree (ec);
+                       }
+
+                       ArrayList args = new ArrayList (2);
+                       args.Add (new Argument (instance));
+                       args.Add (new Argument (CreateTypeOfExpression ()));
+                       return CreateExpressionFactoryCall ("Field", args);
+               }
+
+               public Expression CreateTypeOfExpression ()
+               {
+                       return new TypeOfField (FieldInfo, loc);
+               }
+
                override public Expression DoResolve (EmitContext ec)
                {
                        return DoResolve (ec, false, false);
@@ -4584,7 +4742,7 @@ namespace Mono.CSharp {
 
                        // If the instance expression is a local variable or parameter.
                        IVariable var = InstanceExpression as IVariable;
-                       if ((var == null) || (var.VariableInfo == null))
+                       if (var == null || var.VariableInfo == null)
                                return this;
 
                        VariableInfo vi = var.VariableInfo;
@@ -4635,7 +4793,7 @@ namespace Mono.CSharp {
                override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
                {
                        IVariable var = InstanceExpression as IVariable;
-                       if ((var != null) && (var.VariableInfo != null))
+                       if (var != null && var.VariableInfo != null)
                                var.VariableInfo.SetFieldAssigned (ec, FieldInfo.Name);
 
                        bool lvalue_instance = !FieldInfo.IsStatic && FieldInfo.DeclaringType.IsValueType;
@@ -4683,28 +4841,34 @@ namespace Mono.CSharp {
                        return this;
                }
 
+               bool is_marshal_by_ref ()
+               {
+                       return !IsStatic && Type.IsValueType && TypeManager.mbr_type != null && TypeManager.IsSubclassOf (DeclaringType, TypeManager.mbr_type);
+               }
+
                public override void CheckMarshalByRefAccess (EmitContext ec)
                {
-                       if (!IsStatic && Type.IsValueType && !(InstanceExpression is This) && TypeManager.mbr_type != null && TypeManager.IsSubclassOf (DeclaringType, TypeManager.mbr_type)) {
+                       if (is_marshal_by_ref () && !(InstanceExpression is This)) {
                                Report.SymbolRelatedToPreviousError (DeclaringType);
                                Report.Warning (1690, 1, loc, "Cannot call methods, properties, or indexers on `{0}' because it is a value type member of a marshal-by-reference class",
                                                GetSignatureForError ());
                        }
                }
 
-               public bool VerifyFixed ()
-               {
-                       IVariable variable = InstanceExpression as IVariable;
-                       // A variable of the form V.I is fixed when V is a fixed variable of a struct type.
-                       // We defer the InstanceExpression check after the variable check to avoid a 
-                       // separate null check on InstanceExpression.
-                       return variable != null && InstanceExpression.Type.IsValueType && variable.VerifyFixed ();
-               }
-
                public override int GetHashCode ()
                {
                        return FieldInfo.GetHashCode ();
                }
+               
+               public bool IsFixed {
+                       get {
+                               IVariable variable = InstanceExpression as IVariable;
+                               // A variable of the form V.I is fixed when V is a fixed variable of a struct type.
+                               // We defer the InstanceExpression check after the variable check to avoid a 
+                               // separate null check on InstanceExpression.
+                               return variable != null && InstanceExpression.Type.IsValueType && variable.IsFixed;
+                       }
+               }               
 
                public override bool Equals (object obj)
                {
@@ -4776,10 +4940,7 @@ namespace Mono.CSharp {
                                return;
                        }
 
-                       //
-                       // String concatenation creates a new string instance 
-                       //
-                       prepared = prepare_for_load && !(source is StringConcat);
+                       prepared = prepare_for_load;
                        EmitInstance (ec, prepared);
 
                        source.Emit (ec);                       
@@ -4815,6 +4976,15 @@ namespace Mono.CSharp {
                        Emit (ec, false);
                }
 
+               public override void EmitSideEffect (EmitContext ec)
+               {
+                       FieldBase f = TypeManager.GetField (FieldInfo);
+                       bool is_volatile = f != null && (f.ModFlags & Modifiers.VOLATILE) != 0;
+
+                       if (is_volatile || is_marshal_by_ref ())
+                               base.EmitSideEffect (ec);
+               }
+
                public void AddressOf (EmitContext ec, AddressOp mode)
                {
                        ILGenerator ig = ec.ig;
@@ -4919,18 +5089,30 @@ namespace Mono.CSharp {
 
                public override Expression CreateExpressionTree (EmitContext ec)
                {
+                       ArrayList args;
                        if (IsSingleDimensionalArrayLength ()) {
-                               ArrayList args = new ArrayList (1);
+                               args = new ArrayList (1);
                                args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
                                return CreateExpressionFactoryCall ("ArrayLength", args);
                        }
 
-                       // TODO: it's waiting for PropertyExpr refactoring
-                       //ArrayList args = new ArrayList (2);
-                       //args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
-                       //args.Add (getter expression);
-                       //return CreateExpressionFactoryCall ("Property", args);
-                       return base.CreateExpressionTree (ec);
+                       if (is_base) {
+                               Error_BaseAccessInExpressionTree (loc);
+                               return null;
+                       }
+
+                       args = new ArrayList (2);
+                       if (InstanceExpression == null)
+                               args.Add (new Argument (new NullLiteral (loc)));
+                       else
+                               args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
+                       args.Add (new Argument (new TypeOfMethodInfo (getter, loc)));
+                       return CreateExpressionFactoryCall ("Property", args);
+               }
+
+               public Expression CreateSetterTypeOfExpression ()
+               {
+                       return new TypeOfMethodInfo (setter, loc);
                }
 
                public override Type DeclaringType {
@@ -5046,7 +5228,7 @@ namespace Mono.CSharp {
                                Error_TypeDoesNotContainDefinition (loc, PropertyInfo.DeclaringType, Name);
                                return;
                        }
-
+                       
                        StringBuilder sig = new StringBuilder (TypeManager.CSharpName (mi.DeclaringType));
                        sig.Append ('.');
                        ParameterData iparams = TypeManager.GetParameterData (mi);
@@ -5070,18 +5252,12 @@ namespace Mono.CSharp {
 
                bool IsSingleDimensionalArrayLength ()
                {
-                       if (getter == TypeManager.system_int_array_get_length ||
-                               getter == TypeManager.int_array_get_length) {
-                               Type iet = InstanceExpression.Type;
-
-                               //
-                               // System.Array.Length can be called, but the Type does not
-                               // support invoking GetArrayRank, so test for that case first
-                               //
-                               return iet != TypeManager.array_type && (iet.GetArrayRank () == 1);
-                       }
+                       if (DeclaringType != TypeManager.array_type || getter == null || Name != "Length")
+                               return false;
 
-                       return false;
+                       string t_name = InstanceExpression.Type.Name;
+                       int t_name_len = t_name.Length;
+                       return t_name_len > 2 && t_name [t_name_len - 2] == '[';
                }
 
                override public Expression DoResolve (EmitContext ec)
@@ -5252,14 +5428,9 @@ namespace Mono.CSharp {
                        Expression my_source = source;
 
                        if (prepare_for_load) {
-                               if (source is StringConcat)
-                                       EmitInstance (ec, false);
-                               else
-                                       prepared = true;                                        
-
+                               prepared = true;
                                source.Emit (ec);
                                
-                               prepared = true;
                                if (leave_copy) {
                                        ec.ig.Emit (OpCodes.Dup);
                                        if (!is_static) {
@@ -5376,7 +5547,6 @@ namespace Mono.CSharp {
                        return base.ResolveMemberAccess (ec, left, loc, original);
                }
 
-
                bool InstanceResolve (EmitContext ec, bool must_do_cs1540_check)
                {
                        if (is_static) {
@@ -5420,9 +5590,16 @@ namespace Mono.CSharp {
                                IsAccessorAccessible (invocation_type, remove_accessor, out dummy);
                }
 
+               public override Expression CreateExpressionTree (EmitContext ec)
+               {
+                       throw new NotSupportedException ("ET");
+               }
+
                public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
                {
-                       return DoResolve (ec);
+                       // contexts where an LValue is valid have already devolved to FieldExprs
+                       Error_CannotAssign ();
+                       return null;
                }
 
                public override Expression DoResolve (EmitContext ec)
@@ -5437,14 +5614,25 @@ namespace Mono.CSharp {
 
                        if (!InstanceResolve (ec, must_do_cs1540_check))
                                return null;
+
+                       if (!ec.IsInCompoundAssignment) {
+                               Error_CannotAssign ();
+                               return null;
+                       }
                        
                        return this;
                }               
 
                public override void Emit (EmitContext ec)
                {
-                       Report.Error (70, loc, "The event `{0}' can only appear on the left hand side of += or -= "+
-                                     "(except on the defining type)", GetSignatureForError ());
+                       Error_CannotAssign ();
+               }
+
+               public void Error_CannotAssign ()
+               {
+                       Report.Error (70, loc,
+                               "The event `{0}' can only appear on the left hand side of += or -= when used outside of the type `{1}'",
+                               GetSignatureForError (), TypeManager.CSharpName (EventInfo.DeclaringType));
                }
 
                public override string GetSignatureForError ()
@@ -5452,46 +5640,36 @@ namespace Mono.CSharp {
                        return TypeManager.CSharpSignature (EventInfo);
                }
 
-               public void EmitAddOrRemove (EmitContext ec, Expression source)
+               public void EmitAddOrRemove (EmitContext ec, bool is_add, Expression source)
                {
-                       BinaryDelegate source_del = source as BinaryDelegate;
-                       if (source_del == null) {
-                               Emit (ec);
-                               return;
-                       }
-                       Expression handler = source_del.Right;
-                       
-                       Argument arg = new Argument (handler, Argument.AType.Expression);
-                       ArrayList args = new ArrayList ();
-                               
-                       args.Add (arg);
-                       
-                       if (source_del.IsAddition)
-                               Invocation.EmitCall (
-                                       ec, IsBase, InstanceExpression, add_accessor, args, loc);
-                       else
-                               Invocation.EmitCall (
-                                       ec, IsBase, InstanceExpression, remove_accessor, args, loc);
+                       ArrayList args = new ArrayList (1);
+                       args.Add (new Argument (source, Argument.AType.Expression));
+                       Invocation.EmitCall (ec, IsBase, InstanceExpression, is_add ? add_accessor : remove_accessor, args, loc);
                }
        }
 
-       public class TemporaryVariable : Expression, IMemoryLocation
+       public class TemporaryVariable : VariableReference
        {
                LocalInfo li;
                Variable var;
-               
+
                public TemporaryVariable (Type type, Location loc)
                {
                        this.type = type;
                        this.loc = loc;
-                       eclass = ExprClass.Value;
+                       eclass = ExprClass.Variable;
                }
-               
+
+               public override Expression CreateExpressionTree (EmitContext ec)
+               {
+                       throw new NotSupportedException ("ET");
+               }
+
                public override Expression DoResolve (EmitContext ec)
                {
                        if (li != null)
                                return this;
-                       
+
                        TypeExpr te = new TypeExpression (type, loc);
                        li = ec.CurrentBlock.AddTemporaryVariable (te, loc);
                        if (!li.Resolve (ec))
@@ -5502,46 +5680,34 @@ namespace Mono.CSharp {
                                var = scope.AddLocal (li);
                                type = var.Type;
                        }
-                       
+
                        return this;
                }
 
-               public Variable Variable {
-                       get { return var != null ? var : li.Variable; }
-               }
-               
                public override void Emit (EmitContext ec)
                {
-                       Variable.EmitInstance (ec);
-                       Variable.Emit (ec);
+                       Emit (ec, false);
                }
-               
-               public void EmitLoadAddress (EmitContext ec)
+
+               public void EmitAssign (EmitContext ec, Expression source)
                {
-                       Variable.EmitInstance (ec);
-                       Variable.EmitAddressOf (ec);
+                       EmitAssign (ec, source, false, false);
                }
-               
-               public void Store (EmitContext ec, Expression right_side)
-               {
-                       Variable.EmitInstance (ec);
-                       right_side.Emit (ec);
-                       Variable.EmitAssign (ec);
+
+               public override bool IsFixed {
+                       get { return true; }
                }
-               
-               public void EmitThis (EmitContext ec)
-               {
-                       Variable.EmitInstance (ec);
+
+               public override bool IsRef {
+                       get { return false; }
                }
-               
-               public void EmitStore (EmitContext ec)
-               {
-                       Variable.EmitAssign (ec);
+
+               public override Variable Variable {
+                       get { return var != null ? var : li.Variable; }
                }
-               
-               public void AddressOf (EmitContext ec, AddressOp mode)
-               {
-                       EmitLoadAddress (ec);
+
+               public override VariableInfo VariableInfo {
+                       get { throw new NotImplementedException (); }
                }
        }
 
@@ -5565,7 +5731,7 @@ namespace Mono.CSharp {
                        }
                }
 
-               public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
+               public bool InferType (EmitContext ec, Expression right_side)
                {
                        if (type != null)
                                throw new InternalErrorException ("An implicitly typed local variable could not be redefined");
@@ -5574,11 +5740,11 @@ namespace Mono.CSharp {
                        if (type == TypeManager.null_type || type == TypeManager.void_type || type == TypeManager.anonymous_method_type) {
                                Report.Error (815, loc, "An implicitly typed local variable declaration cannot be initialized with `{0}'",
                                              right_side.GetSignatureForError ());
-                               return null;
+                               return false;
                        }
 
                        eclass = ExprClass.Variable;
-                       return this;
+                       return true;
                }
 
                protected override void Error_TypeOrNamespaceNotFound (IResolveContext ec)