Switch to compiler-tester
[mono.git] / mcs / mbas / statement.cs
index fccab1999bc89032acbbc7be7c4b8e366b81a9cc..889bcc852fab7aff74ae93be46291cefe7063fec 100644 (file)
@@ -3,16 +3,21 @@
 //
 // Author:
 //   Miguel de Icaza (miguel@ximian.com)
+//   Martin Baulig (martin@gnome.org)
+//      Anirban Bhattacharjee (banirban@novell.com)
+//   Manjula GHM (mmanjula@novell.com)
+//   Satya Sudha K (ksathyasudha@novell.com)
 //
 // (C) 2001, 2002 Ximian, Inc.
 //
 
 using System;
+using System.Text;
 using System.Reflection;
 using System.Reflection.Emit;
 using System.Diagnostics;
 
-namespace Mono.CSharp {
+namespace Mono.MonoBASIC {
 
        using System.Collections;
        
@@ -31,7 +36,17 @@ namespace Mono.CSharp {
                /// <summary>
                ///   Return value indicates whether all code paths emitted return.
                /// </summary>
-               public abstract bool Emit (EmitContext ec);
+               protected abstract bool DoEmit (EmitContext ec);
+
+               /// <summary>
+               ///   Return value indicates whether all code paths emitted return.
+               /// </summary>
+               public virtual bool Emit (EmitContext ec)
+               {
+                       ec.Mark (loc);
+                       Report.Debug (8, "MARK", this, loc);
+                       return DoEmit (ec);
+               }
                
                public static Expression ResolveBoolean (EmitContext ec, Expression e, Location loc)
                {
@@ -40,26 +55,29 @@ namespace Mono.CSharp {
                                return null;
                        
                        if (e.Type != TypeManager.bool_type){
-                               e = Expression.ConvertImplicit (ec, e, TypeManager.bool_type,
-                                                               new Location (-1));
+                               e = Expression.ConvertImplicit (ec, e, TypeManager.bool_type, Location.Null);
                        }
 
                        if (e == null){
                                Report.Error (
-                                       31, loc, "Can not convert the expression to a boolean");
+                                       30311, loc, "Can not convert the expression to a boolean");
                        }
 
-                       if (CodeGen.SymbolWriter != null)
-                               ec.Mark (loc);
+                       ec.Mark (loc);
 
                        return e;
                }
                
                /// <remarks>
-               ///    Emits a bool expression.
+               ///    Encapsulates the emission of a boolean test and jumping to a
+               ///    destination.
+               ///
+               ///    This will emit the bool expression in `bool_expr' and if
+               ///    `target_is_for_true' is true, then the code will generate a 
+               ///    brtrue to the target.   Otherwise a brfalse. 
                /// </remarks>
                public static void EmitBoolExpression (EmitContext ec, Expression bool_expr,
-                                                      Label target, bool isTrue)
+                                                      Label target, bool target_is_for_true)
                {
                        ILGenerator ig = ec.ig;
                        
@@ -72,12 +90,17 @@ namespace Mono.CSharp {
 
                                        u.EmitLogicalNot (ec);
                                }
-                       } 
+                       } else if (bool_expr is Binary){
+                               Binary b = (Binary) bool_expr;
+
+                               if (b.EmitBranchable (ec, target, target_is_for_true))
+                                       return;
+                       }
 
                        if (!invert)
                                bool_expr.Emit (ec);
 
-                       if (isTrue){
+                       if (target_is_for_true){
                                if (invert)
                                        ig.Emit (OpCodes.Brfalse, target);
                                else
@@ -102,7 +125,7 @@ namespace Mono.CSharp {
                        return true;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        return false;
                }
@@ -133,24 +156,35 @@ namespace Mono.CSharp {
 
                public override bool Resolve (EmitContext ec)
                {
+                       Report.Debug (1, "START IF BLOCK", loc);
+
                        expr = ResolveBoolean (ec, expr, loc);
                        if (expr == null){
                                return false;
                        }
                        
-                       if (TrueStatement.Resolve (ec)){
-                               if (FalseStatement != null){
-                                       if (FalseStatement.Resolve (ec))
-                                               return true;
-                                       
-                                       return false;
-                               }
-                               return true;
+                       ec.StartFlowBranching (FlowBranchingType.BLOCK, loc);
+                       
+                       if (!TrueStatement.Resolve (ec)) {
+                               ec.KillFlowBranching ();
+                               return false;
                        }
-                       return false;
+
+                       ec.CurrentBranching.CreateSibling ();
+
+                       if ((FalseStatement != null) && !FalseStatement.Resolve (ec)) {
+                               ec.KillFlowBranching ();
+                               return false;
+                       }
+                                       
+                       ec.EndFlowBranching ();
+
+                       Report.Debug (1, "END IF BLOCK", loc);
+
+                       return true;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        ILGenerator ig = ec.ig;
                        Label false_target = ig.DefineLabel ();
@@ -176,7 +210,7 @@ namespace Mono.CSharp {
                        }
                        
                        EmitBoolExpression (ec, expr, false_target, false);
-                       
+
                        is_true_ret = TrueStatement.Emit (ec);
                        is_false_ret = is_true_ret;
 
@@ -188,7 +222,7 @@ namespace Mono.CSharp {
                                        ig.Emit (OpCodes.Br, end);
                                        branch_emitted = true;
                                }
-                       
+
                                ig.MarkLabel (false_target);
                                is_false_ret = FalseStatement.Emit (ec);
 
@@ -203,80 +237,124 @@ namespace Mono.CSharp {
                }
        }
 
+       public enum DoOptions {
+               WHILE,
+               UNTIL,
+               TEST_BEFORE,
+               TEST_AFTER
+       };
+
        public class Do : Statement {
                public Expression expr;
                public readonly Statement  EmbeddedStatement;
+               //public DoOptions type;
+               public DoOptions test;
+               bool infinite, may_return;
+
                
-               public Do (Statement statement, Expression boolExpr, Location l)
+               public Do (Statement statement, Expression boolExpr, DoOptions do_test, Location l)
                {
                        expr = boolExpr;
                        EmbeddedStatement = statement;
+//                     type = do_type;
+                       test = do_test;
                        loc = l;
                }
 
                public override bool Resolve (EmitContext ec)
                {
+                       bool ok = true;
+
+                       ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+
+                       if (!EmbeddedStatement.Resolve (ec))
+                               ok = false;
+
                        expr = ResolveBoolean (ec, expr, loc);
                        if (expr == null)
-                               return false;
-                       
-                       return EmbeddedStatement.Resolve (ec);
+                               ok = false;
+                       else if (expr is BoolConstant){
+                               bool res = ((BoolConstant) expr).Value;
+
+                               if (res)
+                                       infinite = true;
+                       }
+
+                       ec.CurrentBranching.Infinite = infinite;
+                       FlowReturns returns = ec.EndFlowBranching ();
+                       may_return = returns != FlowReturns.NEVER;
+
+                       return ok;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        ILGenerator ig = ec.ig;
                        Label loop = ig.DefineLabel ();
                        Label old_begin = ec.LoopBegin;
                        Label old_end = ec.LoopEnd;
                        bool  old_inloop = ec.InLoop;
-                       bool old_breaks = ec.Breaks;
+                       int old_loop_begin_try_catch_level = ec.LoopBeginTryCatchLevel;
                        
                        ec.LoopBegin = ig.DefineLabel ();
                        ec.LoopEnd = ig.DefineLabel ();
                        ec.InLoop = true;
-                               
-                       ig.MarkLabel (loop);
-                       ec.Breaks = false;
-                       EmbeddedStatement.Emit (ec);
-                       bool breaks = ec.Breaks;
-                       ig.MarkLabel (ec.LoopBegin);
+                       ec.LoopBeginTryCatchLevel = ec.TryCatchLevel;
 
-                       //
-                       // Dead code elimination
-                       //
-                       if (expr is BoolConstant){
-                               bool res = ((BoolConstant) expr).Value;
+                       if (test == DoOptions.TEST_AFTER) {
+                               ig.MarkLabel (loop);
+                               EmbeddedStatement.Emit (ec);
+                               ig.MarkLabel (ec.LoopBegin);
 
-                               if (res)
-                                       ec.ig.Emit (OpCodes.Br, loop); 
-                       } else
-                               EmitBoolExpression (ec, expr, loop, true);
-                       
-                       ig.MarkLabel (ec.LoopEnd);
+                               //
+                               // Dead code elimination
+                               //
+                               if (expr is BoolConstant){
+                                       bool res = ((BoolConstant) expr).Value;
 
+                                       if (res)
+                                               ec.ig.Emit (OpCodes.Br, loop);
+                               } else
+                                       EmitBoolExpression (ec, expr, loop, true);
+
+                               ig.MarkLabel (ec.LoopEnd);
+                       }
+                       else
+                       {
+                               ig.MarkLabel (loop);
+                               ig.MarkLabel (ec.LoopBegin);
+
+                               //
+                               // Dead code elimination
+                               //
+                               if (expr is BoolConstant){
+                                       bool res = ((BoolConstant) expr).Value;
+
+                                       if (res)
+                                               ec.ig.Emit (OpCodes.Br, ec.LoopEnd);
+                               } else
+                                       EmitBoolExpression (ec, expr, ec.LoopEnd, true);
+
+                               EmbeddedStatement.Emit (ec);
+                               ec.ig.Emit (OpCodes.Br, loop);
+                               ig.MarkLabel (ec.LoopEnd);
+                       }
+                       ec.LoopBeginTryCatchLevel = old_loop_begin_try_catch_level;
                        ec.LoopBegin = old_begin;
                        ec.LoopEnd = old_end;
                        ec.InLoop = old_inloop;
-                       ec.Breaks = old_breaks;
 
-                       //
-                       // Inform whether we are infinite or not
-                       //
-                       if (expr is BoolConstant){
-                               BoolConstant bc = (BoolConstant) expr;
-
-                               if (bc.Value == true)
-                                       return breaks == false;
-                       }
-                       
-                       return false;
+                       if (infinite)
+                               return may_return == false;
+                       else
+                               return false;
                }
        }
 
        public class While : Statement {
                public Expression expr;
                public readonly Statement Statement;
+               bool may_return, empty, infinite;
                
                public While (Expression boolExpr, Statement statement, Location l)
                {
@@ -287,56 +365,83 @@ namespace Mono.CSharp {
 
                public override bool Resolve (EmitContext ec)
                {
+                       bool ok = true;
+
                        expr = ResolveBoolean (ec, expr, loc);
                        if (expr == null)
                                return false;
-                       
-                       return Statement.Resolve (ec);
+
+                       ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+
+                       //
+                       // Inform whether we are infinite or not
+                       //
+                       if (expr is BoolConstant){
+                               BoolConstant bc = (BoolConstant) expr;
+
+                               if (bc.Value == false){
+                                       Warning_DeadCodeFound (Statement.loc);
+                                       empty = true;
+                               } else
+                                       infinite = true;
+                       } else {
+                               //
+                               // We are not infinite, so the loop may or may not be executed.
+                               //
+                               ec.CurrentBranching.CreateSibling ();
+                       }
+
+                       if (!Statement.Resolve (ec))
+                               ok = false;
+
+                       if (empty)
+                               ec.KillFlowBranching ();
+                       else {
+                               ec.CurrentBranching.Infinite = infinite;
+                               FlowReturns returns = ec.EndFlowBranching ();
+                               may_return = returns != FlowReturns.NEVER;
+                       }
+
+                       return ok;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
+                       if (empty)
+                               return false;
+
                        ILGenerator ig = ec.ig;
                        Label old_begin = ec.LoopBegin;
                        Label old_end = ec.LoopEnd;
                        bool old_inloop = ec.InLoop;
-                       bool old_breaks = ec.Breaks;
-                       Label while_loop = ig.DefineLabel ();
+                       int old_loop_begin_try_catch_level = ec.LoopBeginTryCatchLevel;
                        bool ret;
                        
                        ec.LoopBegin = ig.DefineLabel ();
                        ec.LoopEnd = ig.DefineLabel ();
                        ec.InLoop = true;
-
-                       ig.Emit (OpCodes.Br, ec.LoopBegin);
-                       ig.MarkLabel (while_loop);
+                       ec.LoopBeginTryCatchLevel = ec.TryCatchLevel;
 
                        //
                        // Inform whether we are infinite or not
                        //
                        if (expr is BoolConstant){
-                               BoolConstant bc = (BoolConstant) expr;
-
                                ig.MarkLabel (ec.LoopBegin);
-                               if (bc.Value == false){
-                                       Warning_DeadCodeFound (Statement.loc);
-                                       ret = false;
-                               } else {
-                                       bool breaks;
-                                       
-                                       ec.Breaks = false;
-                                       Statement.Emit (ec);
-                                       breaks = ec.Breaks;
-                                       ig.Emit (OpCodes.Br, ec.LoopBegin);
+                               Statement.Emit (ec);
+                               ig.Emit (OpCodes.Br, ec.LoopBegin);
                                        
-                                       //
-                                       // Inform that we are infinite (ie, `we return'), only
-                                       // if we do not `break' inside the code.
-                                       //
-                                       ret = breaks == false;
-                               }
+                               //
+                               // Inform that we are infinite (ie, `we return'), only
+                               // if we do not `break' inside the code.
+                               //
+                               ret = may_return == false;
                                ig.MarkLabel (ec.LoopEnd);
                        } else {
+                               Label while_loop = ig.DefineLabel ();
+
+                               ig.Emit (OpCodes.Br, ec.LoopBegin);
+                               ig.MarkLabel (while_loop);
+
                                Statement.Emit (ec);
                        
                                ig.MarkLabel (ec.LoopBegin);
@@ -350,39 +455,177 @@ namespace Mono.CSharp {
                        ec.LoopBegin = old_begin;
                        ec.LoopEnd = old_end;
                        ec.InLoop = old_inloop;
-                       ec.Breaks = old_breaks;
+                       ec.LoopBeginTryCatchLevel = old_loop_begin_try_catch_level;
 
                        return ret;
                }
        }
 
        public class For : Statement {
-               Expression Test;
-               readonly Statement InitStatement;
-               readonly Statement Increment;
-               readonly Statement Statement;
-               
-               public For (Statement initStatement,
-                           Expression test,
-                           Statement increment,
+               Expression LoopControlVar;
+               Expression Start;
+               Expression Limit;
+               Expression StepValue;
+               Statement statement, Increment;
+               bool may_return, infinite, empty;
+               private Statement InitStatement;
+               // required when loop control var is of type 'Object'
+               Expression Test, AddnTest;
+               LocalTemporary ltmp;
+               bool is_lcv_object;
+               
+               public For (Expression loopVar,
+                           Expression start,
+                           Expression limit,
+                           Expression stepVal,
                            Statement statement,
                            Location l)
                {
-                       InitStatement = initStatement;
-                       Test = test;
-                       Increment = increment;
-                       Statement = statement;
+                       LoopControlVar = loopVar;
+                       Start = start;
+                       Limit = limit;
+                       StepValue = stepVal;
+                       this.statement = statement;
                        loc = l;
+                       ltmp = null;
+
+                       InitStatement = new StatementExpression ((ExpressionStatement) (new Assign (LoopControlVar, Start, loc)), loc);
+                       Increment = new StatementExpression (
+                                               (ExpressionStatement) (new CompoundAssign (Binary.Operator.Addition, 
+                                                                       LoopControlVar, StepValue, loc)), loc);
+                       AddnTest = null;
+                       is_lcv_object = false;
                }
 
                public override bool Resolve (EmitContext ec)
                {
                        bool ok = true;
 
-                       if (Test != null){
-                               Test = ResolveBoolean (ec, Test, loc);
+                       LoopControlVar = LoopControlVar.Resolve (ec);
+                       if (LoopControlVar == null)
+                               return false;
+
+                       Start = Start.Resolve (ec);
+                       Limit = Limit.Resolve (ec);
+                       StepValue = StepValue.Resolve (ec);
+                       if (StepValue == null || Start == null || Limit == null)
+                               return false;
+
+                       double value = 0;
+                       if (StepValue is Constant) {
+
+                               value = GetValue (StepValue);
+                               if (value > 0) // Positive Step value
+                                       Test = new Binary (Binary.Operator.LessThanOrEqual, LoopControlVar, Limit, loc);
+                               else if (value < 0)
+                                       Test = new Binary (Binary.Operator.GreaterThanOrEqual, LoopControlVar, Limit, loc);
+                       }
+
+                       if (Start is Constant && Limit is Constant) {
+                               if (value > 0)
+                                       AddnTest = ConstantFold.BinaryFold (ec, Binary.Operator.LessThanOrEqual,
+                                                                           (Constant) Start, (Constant) Limit, loc);
+                               else  if (value < 0)
+                                       AddnTest = ConstantFold.BinaryFold (ec, Binary.Operator.GreaterThanOrEqual,
+                                                                           (Constant) Start, (Constant) Limit, loc);
+                       }
+
+
+                       string method_to_call = null;
+                       Binary left, right;
+                       left = right = null;
+
+                       switch (Type.GetTypeCode (LoopControlVar.Type)) {
+                       case TypeCode.Boolean :
+                       case TypeCode.Char :
+                       case TypeCode.DateTime :
+                       case TypeCode.String :
+                               Report.Error (30337,loc,"'For' loop control variable cannot be of type '" + LoopControlVar.Type + "'");
+                               return false;
+                       case TypeCode.Byte :
                                if (Test == null)
-                                       ok = false;
+                                       Test = new Binary (Binary.Operator.LessThanOrEqual, LoopControlVar, Limit, loc);
+                               break;
+                       case TypeCode.Int16 :
+                               if (Test == null) {
+                                       left = new Binary (Binary.Operator.ExclusiveOr, 
+                                                          new Binary (Binary.Operator.RightShift, StepValue, new IntLiteral (15), loc),
+                                                          LoopControlVar, 
+                                                          loc);
+                                       right = new Binary (Binary.Operator.ExclusiveOr, 
+                                                           new Binary (Binary.Operator.RightShift, StepValue, new IntLiteral (15), loc),
+                                                           Limit, 
+                                                           loc);
+                                       Test = new Binary (Binary.Operator.LessThanOrEqual, left, right, loc);
+                               }
+                               break;
+                       case TypeCode.Int32 :
+                               if (Test == null) {
+                                       left = new Binary (Binary.Operator.ExclusiveOr, 
+                                                          new Binary (Binary.Operator.RightShift, StepValue, new IntLiteral (31), loc),
+                                                          LoopControlVar, 
+                                                          loc);
+                                       right = new Binary (Binary.Operator.ExclusiveOr, 
+                                                           new Binary (Binary.Operator.RightShift, StepValue, new IntLiteral (31), loc),
+                                                           Limit, 
+                                                           loc);
+                                       Test = new Binary (Binary.Operator.LessThanOrEqual, left, right, loc);
+                               }
+                               break;
+                       case TypeCode.Int64 :
+                               if (Test == null) {
+                                       left = new Binary (Binary.Operator.ExclusiveOr, 
+                                                          new Binary (Binary.Operator.RightShift, StepValue, new IntLiteral (63), loc),
+                                                          LoopControlVar, 
+                                                          loc);
+                                       right = new Binary (Binary.Operator.ExclusiveOr, 
+                                                           new Binary (Binary.Operator.RightShift, StepValue, new IntLiteral (63), loc),
+                                                           Limit, 
+                                                           loc);
+                                       Test = new Binary (Binary.Operator.LessThanOrEqual, left, right, loc);
+                               }
+                               break;
+                       case TypeCode.Decimal :
+                               method_to_call = "Microsoft.VisualBasic.CompilerServices.FlowControl.ForNextCheckDec";
+                               break;
+                       case TypeCode.Single :
+                               method_to_call = "Microsoft.VisualBasic.CompilerServices.FlowControl.ForNextCheckR4";
+                               break;
+                       case TypeCode.Double :
+                               method_to_call = "Microsoft.VisualBasic.CompilerServices.FlowControl.ForNextCheckR8";
+                               break;
+                       case TypeCode.Object :
+                               is_lcv_object = true;
+                               ArrayList initArgs = new ArrayList ();
+                               initArgs.Add (new Argument (LoopControlVar, Argument.AType.Expression));
+                               initArgs.Add (new Argument (Start, Argument.AType.Expression));
+                               initArgs.Add (new Argument (Limit, Argument.AType.Expression));
+                               initArgs.Add (new Argument (StepValue, Argument.AType.Expression));
+                               ltmp = new LocalTemporary (ec, TypeManager.object_type);
+                               initArgs.Add (new Argument (ltmp, Argument.AType.Ref));
+                               initArgs.Add (new Argument (LoopControlVar, Argument.AType.Ref));
+                               Expression sname  = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.FlowControl.ForLoopInitObj", loc);
+                               AddnTest = new Invocation (sname, initArgs, loc);
+                               //AddnTest = new Binary (Binary.Operator.Inequality, inv, new BoolLiteral (false), loc);
+                               ArrayList args = new ArrayList ();
+                               args.Add (new Argument (LoopControlVar, Argument.AType.Expression));
+                               args.Add (new Argument (ltmp, Argument.AType.Expression));
+                               args.Add (new Argument (LoopControlVar, Argument.AType.Ref));
+                               sname  = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.FlowControl.ForNextCheckObj", loc);
+                               Test = new Invocation (sname, args, loc);
+                               //Test = new Binary (Binary.Operator.Inequality, inv, new BoolLiteral (false), loc);
+                               break;
+                       }
+
+                       if (method_to_call != null && !method_to_call.Equals ("")) {
+                               ArrayList args = null;
+                               args = new ArrayList ();
+                               args.Add (new Argument (LoopControlVar, Argument.AType.Expression));
+                               args.Add (new Argument (Limit, Argument.AType.Expression));
+                               args.Add (new Argument (StepValue, Argument.AType.Expression));
+                               Expression sname = Parser.DecomposeQI (method_to_call, loc);
+                               Test = new Invocation (sname, args, loc);
+                               //Test = new Binary (Binary.Operator.Inequality, invocation, new BoolLiteral (false), loc);
                        }
 
                        if (InitStatement != null){
@@ -390,73 +633,143 @@ namespace Mono.CSharp {
                                        ok = false;
                        }
 
-                       if (Increment != null){
+                       if (AddnTest != null) {
+                               AddnTest = ResolveBoolean (ec, AddnTest, loc);
+                               if (AddnTest == null)
+                                       ok = false;
+                       }
+
+                       if (Test != null){
+                               Test = ResolveBoolean (ec, Test, loc);
+                               if (Test == null)
+                                       ok = false;
+                               else if (Test is BoolConstant){
+                                       BoolConstant bc = (BoolConstant) Test;
+
+                                       if (bc.Value == false){
+                                               Warning_DeadCodeFound (statement.loc);
+                                               empty = true;
+                                       } else
+                                               infinite = true;
+                               }
+                       } else
+                               infinite = true;
+
+                       if (Increment != null) {
                                if (!Increment.Resolve (ec))
                                        ok = false;
                        }
-                       
-                       return Statement.Resolve (ec) && ok;
+
+                       ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+                       if (!infinite)
+                               ec.CurrentBranching.CreateSibling ();
+
+                       if (!statement.Resolve (ec))
+                               ok = false;
+
+                       if (empty)
+                               ec.KillFlowBranching ();
+                       else {
+                               ec.CurrentBranching.Infinite = infinite;
+                               FlowReturns returns = ec.EndFlowBranching ();
+                               may_return = returns != FlowReturns.NEVER;
+                       }
+
+                       return ok;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
+                       if (empty)
+                               return false;
+
                        ILGenerator ig = ec.ig;
                        Label old_begin = ec.LoopBegin;
                        Label old_end = ec.LoopEnd;
                        bool old_inloop = ec.InLoop;
-                       bool old_breaks = ec.Breaks;
+                       int old_loop_begin_try_catch_level = ec.LoopBeginTryCatchLevel;
                        Label loop = ig.DefineLabel ();
-
-                       if (InitStatement != null)
+                       Label test = ig.DefineLabel ();
+                       
+                       if (!is_lcv_object && InitStatement != null)
                                if (! (InitStatement is EmptyStatement))
                                        InitStatement.Emit (ec);
 
                        ec.LoopBegin = ig.DefineLabel ();
                        ec.LoopEnd = ig.DefineLabel ();
                        ec.InLoop = true;
-
+                       ec.LoopBeginTryCatchLevel = ec.TryCatchLevel;
+
+                       if (AddnTest != null) {
+                               if (AddnTest is BoolConstant) {
+                                       if (!((BoolConstant) AddnTest).Value)
+                                               // We can actually branch to the end of the loop,
+                                               // but vbc does it this way
+                                               ig.Emit (OpCodes.Br, test);
+                               } else if (is_lcv_object)
+                                       EmitBoolExpression (ec, AddnTest, ec.LoopEnd, false);
+                               else 
+                                       EmitBoolExpression (ec, AddnTest, test, false);
+                       } else 
+                               ig.Emit (OpCodes.Br, test);
                        ig.MarkLabel (loop);
+                       statement.Emit (ec);
+
+                       ig.MarkLabel (ec.LoopBegin);
+                       if (!is_lcv_object && !(Increment is EmptyStatement))
+                               Increment.Emit (ec);
 
+                       ig.MarkLabel (test);
                        //
                        // If test is null, there is no test, and we are just
                        // an infinite loop
                        //
                        if (Test != null)
-                               EmitBoolExpression (ec, Test, ec.LoopEnd, false);
-
-                       ec.Breaks = false;
-                       Statement.Emit (ec);
-                       bool breaks = ec.Breaks;
-
-                       ig.MarkLabel (ec.LoopBegin);
-                       if (!(Increment is EmptyStatement))
-                               Increment.Emit (ec);
-                       ig.Emit (OpCodes.Br, loop);
+                               EmitBoolExpression (ec, Test, loop, true);
+                       else
+                               ig.Emit (OpCodes.Br, loop);
                        ig.MarkLabel (ec.LoopEnd);
 
                        ec.LoopBegin = old_begin;
                        ec.LoopEnd = old_end;
                        ec.InLoop = old_inloop;
-                       ec.Breaks = old_breaks;
+                       ec.LoopBeginTryCatchLevel = old_loop_begin_try_catch_level;
                        
                        //
-                       // Inform whether we are infinite or not
+                       // Inform whether we are infinite or not
                        //
+
+                       if (ltmp != null)
+                               ltmp.Release (ec);
                        if (Test != null){
                                if (Test is BoolConstant){
                                        BoolConstant bc = (BoolConstant) Test;
 
                                        if (bc.Value)
-                                               return breaks == false;
+                                               return may_return == false;
                                }
                                return false;
                        } else
-                               return true;
+                               return may_return == false;
+               }
+
+               private double GetValue (Expression e) {
+                       if (e is DoubleConstant)
+                               return ((DoubleConstant) e).Value;
+                       if (e is FloatConstant)
+                               return (double)((FloatConstant) e).Value;
+                       if (e is IntConstant)
+                               return (double)((IntConstant) e).Value;
+                       if (e is LongConstant)
+                               return (double)((LongConstant) e).Value;
+                       if (e is DecimalConstant)
+                               return (double)((DecimalConstant) e).Value;
+                       return 0;
                }
        }
        
        public class StatementExpression : Statement {
-               Expression expr;
+               public Expression expr;
                
                public StatementExpression (ExpressionStatement expr, Location l)
                {
@@ -470,7 +783,7 @@ namespace Mono.CSharp {
                        return expr != null;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        ILGenerator ig = ec.ig;
                        
@@ -478,7 +791,8 @@ namespace Mono.CSharp {
                                ((ExpressionStatement) expr).EmitStatement (ec);
                        else {
                                expr.Emit (ec);
-                               ig.Emit (OpCodes.Pop);
+                               if (! (expr is StatementSequence))
+                                       ig.Emit (OpCodes.Pop);
                        }
 
                        return false;
@@ -509,10 +823,18 @@ namespace Mono.CSharp {
                                if (Expr == null)
                                        return false;
                        }
+
+                       FlowBranching.UsageVector vector = ec.CurrentBranching.CurrentUsageVector;
+
+                       if (ec.CurrentBranching.InTryBlock ())
+                               ec.CurrentBranching.AddFinallyVector (vector);
+
+                       vector.Returns = FlowReturns.ALWAYS;
+                       vector.Breaks = FlowReturns.ALWAYS;
                        return true;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        if (ec.InFinally){
                                Report.Error (157,loc,"Control can not leave the body of the finally block");
@@ -522,14 +844,14 @@ namespace Mono.CSharp {
                        if (ec.ReturnType == null){
                                if (Expr != null){
                                        Report.Error (127, loc, "Return with a value not allowed here");
-                                       return false;
+                                       return true;
                                }
                        } else {
                                if (Expr == null){
                                        Report.Error (126, loc, "An object of type `" +
-                                                     TypeManager.CSharpName (ec.ReturnType) + "' is " +
+                                                     TypeManager.MonoBASIC_Name (ec.ReturnType) + "' is " +
                                                      "expected for the return statement");
-                                       return false;
+                                       return true;
                                }
 
                                if (Expr.Type != ec.ReturnType)
@@ -537,7 +859,7 @@ namespace Mono.CSharp {
                                                ec, Expr, ec.ReturnType, loc);
 
                                if (Expr == null)
-                                       return false;
+                                       return true;
 
                                Expr.Emit (ec);
 
@@ -545,9 +867,13 @@ namespace Mono.CSharp {
                                        ec.ig.Emit (OpCodes.Stloc, ec.TemporaryReturn ());
                        }
 
-                       if (ec.InTry || ec.InCatch)
+                       if (ec.InTry || ec.InCatch) {
+                               if (!ec.HasReturnLabel) {
+                                       ec.ReturnLabel = ec.ig.DefineLabel ();
+                                       ec.HasReturnLabel = true;
+                               }
                                ec.ig.Emit (OpCodes.Leave, ec.ReturnLabel);
-                       else
+                       else
                                ec.ig.Emit (OpCodes.Ret);
 
                        return true; 
@@ -557,9 +883,24 @@ namespace Mono.CSharp {
        public class Goto : Statement {
                string target;
                Block block;
+               LabeledStatement label;
                
                public override bool Resolve (EmitContext ec)
                {
+                       label = block.LookupLabel (target);
+                       if (label == null){
+                               Report.Error (
+                                       30132, loc,
+                                       "No such label `" + target + "' in this scope");
+                               return false;
+                       }
+
+                       // If this is a forward goto.
+                       if (!label.IsDefined)
+                               label.AddUsageVector (ec.CurrentBranching.CurrentUsageVector);
+
+                       ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.ALWAYS;
+
                        return true;
                }
                
@@ -576,34 +917,31 @@ namespace Mono.CSharp {
                        }
                }
 
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
-                       LabeledStatement label = block.LookupLabel (target);
-
-                       if (label == null){
-                               //
-                               // Maybe we should catch this before?
-                               //
-                               Report.Error (
-                                       159, loc,
-                                       "No such label `" + target + "' in this scope");
-                               return false;
-                       }
                        Label l = label.LabelTarget (ec);
-                       ec.ig.Emit (OpCodes.Br, l);
+                        if (ec.InTry || ec.InCatch)
+                               ec.ig.Emit (OpCodes.Leave, l);
+                       else 
+                               ec.ig.Emit (OpCodes.Br, l);
                        
                        return false;
                }
        }
 
        public class LabeledStatement : Statement {
-               string label_name;
+               public readonly Location Location;
+               //string label_name;
                bool defined;
+               bool referenced;
                Label label;
+
+               ArrayList vectors;
                
-               public LabeledStatement (string label_name)
+               public LabeledStatement (string label_name, Location l)
                {
-                       this.label_name = label_name;
+                       //this.label_name = label_name;
+                       this.Location = l;
                }
 
                public Label LabelTarget (EmitContext ec)
@@ -616,7 +954,41 @@ namespace Mono.CSharp {
                        return label;
                }
 
-               public override bool Emit (EmitContext ec)
+               public bool IsDefined {
+                       get {
+                               return defined;
+                       }
+               }
+
+               public bool HasBeenReferenced {
+                       get {
+                               return referenced;
+                       }
+               }
+
+               public void AddUsageVector (FlowBranching.UsageVector vector)
+               {
+                       if (vectors == null)
+                               vectors = new ArrayList ();
+
+                       vectors.Add (vector.Clone ());
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       if (vectors != null)
+                               ec.CurrentBranching.CurrentUsageVector.MergeJumpOrigins (vectors);
+                       else {
+                               ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.NEVER;
+                               ec.CurrentBranching.CurrentUsageVector.Returns = FlowReturns.NEVER;
+                       }
+
+                       referenced = true;
+
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
                {
                        LabelTarget (ec);
                        ec.ig.MarkLabel (label);
@@ -636,7 +1008,13 @@ namespace Mono.CSharp {
                        loc = l;
                }
 
-               public override bool Emit (EmitContext ec)
+               public override bool Resolve (EmitContext ec)
+               {
+                       ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.UNREACHABLE;
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
                {
                        if (ec.Switch == null){
                                Report.Error (153, loc, "goto default is only valid in a switch statement");
@@ -644,181 +1022,1751 @@ namespace Mono.CSharp {
                        }
 
                        if (!ec.Switch.GotDefault){
-                               Report.Error (159, loc, "No default target on switch statement");
+                               Report.Error (30132, loc, "No default target on switch statement");
                                return false;
                        }
                        ec.ig.Emit (OpCodes.Br, ec.Switch.DefaultTarget);
                        return false;
                }
-       }
+       }
+
+       /// <summary>
+       ///   `goto case' statement
+       /// </summary>
+       public class GotoCase : Statement {
+               Expression expr;
+               Label label;
+               
+               public GotoCase (Expression e, Location l)
+               {
+                       expr = e;
+                       loc = l;
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       if (ec.Switch == null){
+                               Report.Error (153, loc, "goto case is only valid in a switch statement");
+                               return false;
+                       }
+
+                       expr = expr.Resolve (ec);
+                       if (expr == null)
+                               return false;
+
+                       if (!(expr is Constant)){
+                               Report.Error (30132, loc, "Target expression for goto case is not constant");
+                               return false;
+                       }
+
+                       object val = Expression.ConvertIntLiteral (
+                               (Constant) expr, ec.Switch.SwitchType, loc);
+
+                       if (val == null)
+                               return false;
+                                       
+                       SwitchLabel sl = (SwitchLabel) ec.Switch.Elements [val];
+
+                       if (sl == null){
+                               Report.Error (
+                                       30132, loc,
+                                       "No such label 'case " + val + "': for the goto case");
+                       }
+
+                       label = sl.ILLabelCode;
+
+                       ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.UNREACHABLE;
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       ec.ig.Emit (OpCodes.Br, label);
+                       return true;
+               }
+       }
+       
+       public class Throw : Statement {
+               Expression expr;
+               
+               public Throw (Expression expr, Location l)
+               {
+                       this.expr = expr;
+                       loc = l;
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       if (expr != null){
+                               expr = expr.Resolve (ec);
+                               if (expr == null)
+                                       return false;
+
+                               ExprClass eclass = expr.eclass;
+
+                               if (!(eclass == ExprClass.Variable || eclass == ExprClass.PropertyAccess ||
+                                     eclass == ExprClass.Value || eclass == ExprClass.IndexerAccess)) {
+                                       expr.Error118 ("value, variable, property or indexer access ");
+                                       return false;
+                               }
+
+                               Type t = expr.Type;
+                               
+                               if ((t != TypeManager.exception_type) &&
+                                   !t.IsSubclassOf (TypeManager.exception_type) &&
+                                   !(expr is NullLiteral)) {
+                                       Report.Error (30665, loc,
+                                                     "The type caught or thrown must be derived " +
+                                                     "from System.Exception");
+                                       return false;
+                               }
+                       }
+
+                       ec.CurrentBranching.CurrentUsageVector.Returns = FlowReturns.EXCEPTION;
+                       ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.EXCEPTION;
+                       return true;
+               }
+                       
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       if (expr == null){
+                               if (ec.InCatch)
+                                       ec.ig.Emit (OpCodes.Rethrow);
+                               else {
+                                       Report.Error (
+                                               156, loc,
+                                               "A throw statement with no argument is only " +
+                                               "allowed in a catch clause");
+                               }
+                               return false;
+                       }
+
+                       expr.Emit (ec);
+
+                       ec.ig.Emit (OpCodes.Throw);
+
+                       return true;
+               }
+       }
+
+       // Support 'End' Statement which terminates execution immediately
+
+         public class End : Statement {
+
+                public End (Location l)
+                {
+                        loc = l;
+                }
+
+                public override bool Resolve (EmitContext ec)
+                {
+                        return true;
+                }
+
+                protected override bool DoEmit (EmitContext ec)
+                {
+                       Expression e = null;
+                        Expression tmp = Mono.MonoBASIC.Parser.DecomposeQI (
+                                                "Microsoft.VisualBasic.CompilerServices.ProjectData.EndApp",
+                                                        Location.Null);
+
+                       e = new Invocation (tmp, null, loc);
+                       e.Resolve (ec);
+
+                       if (e == null)
+                               return false;
+                       e.Emit (ec);
+
+                        return true;
+                }
+        }
+
+
+       public class Break : Statement {
+               
+               public Break (Location l)
+               {
+                       loc = l;
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       ec.CurrentBranching.MayLeaveLoop = true;
+                       ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.ALWAYS;
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       ILGenerator ig = ec.ig;
+
+                       if (ec.InLoop == false && ec.Switch == null){
+                               Report.Error (139, loc, "No enclosing loop or switch to continue to");
+                               return false;
+                       }
+
+                       if (ec.InTry || ec.InCatch)
+                               ig.Emit (OpCodes.Leave, ec.LoopEnd);
+                       else
+                               ig.Emit (OpCodes.Br, ec.LoopEnd);
+
+                       return false;
+               }
+       }
+       
+       public enum ExitType {
+               DO, 
+               FOR, 
+               WHILE,
+               SELECT,
+               SUB,
+               FUNCTION,
+               PROPERTY,
+               TRY                     
+       };
+       
+       public class Exit : Statement {
+               public readonly ExitType type;
+               public Exit (ExitType t, Location l)
+               {
+                       loc = l;
+                       type = t;
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       ec.CurrentBranching.MayLeaveLoop = true;
+                       ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.ALWAYS;
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       ILGenerator ig = ec.ig;
+
+                       if (type != ExitType.SUB && type != ExitType.FUNCTION && 
+                               type != ExitType.PROPERTY && type != ExitType.TRY) {
+                               if (ec.InLoop == false && ec.Switch == null){
+                                       if (type == ExitType.FOR)
+                                               Report.Error (30096, loc, "No enclosing FOR loop to exit from");
+                                       if (type == ExitType.WHILE) 
+                                               Report.Error (30097, loc, "No enclosing WHILE loop to exit from");
+                                       if (type == ExitType.DO)
+                                               Report.Error (30089, loc, "No enclosing DO loop to exit from");
+                                       if (type == ExitType.SELECT)
+                                               Report.Error (30099, loc, "No enclosing SELECT to exit from");
+
+                                       return false;
+                               }
+
+                               if (ec.InTry || ec.InCatch)
+                                       ig.Emit (OpCodes.Leave, ec.LoopEnd);
+                               else
+                                       ig.Emit (OpCodes.Br, ec.LoopEnd);
+                       } else {                        
+                               if (ec.InFinally){
+                                       Report.Error (30393, loc, 
+                                               "Control can not leave the body of the finally block");
+                                       return false;
+                               }
+                       
+                               if (ec.InTry || ec.InCatch) {
+                                       if (!ec.HasReturnLabel) {
+                                               ec.ReturnLabel = ec.ig.DefineLabel ();
+                                               ec.HasReturnLabel = true;
+                                       }
+                                       ec.ig.Emit (OpCodes.Leave, ec.ReturnLabel);
+                               } else {
+                                       if(type == ExitType.SUB) {   
+                                                ec.ig.Emit (OpCodes.Ret);
+                                        } else {
+                                               ec.ig.Emit (OpCodes.Ldloc_0);
+                                               ec.ig.Emit (OpCodes.Ret);
+                                       }
+
+                               }
+
+                               return true; 
+                       }
+                       
+                       return false;
+               }
+       }       
+
+       public class Continue : Statement {
+               
+               public Continue (Location l)
+               {
+                       loc = l;
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.ALWAYS;
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       Label begin = ec.LoopBegin;
+                       
+                       if (!ec.InLoop){
+                               Report.Error (139, loc, "No enclosing loop to continue to");
+                               return false;
+                       } 
+
+                       //
+                       // UGH: Non trivial.  This Br might cross a try/catch boundary
+                       // How can we tell?
+                       //
+                       // while () {
+                       //   try { ... } catch { continue; }
+                       // }
+                       //
+                       // From:
+                       // try {} catch { while () { continue; }}
+                       //
+                       if (ec.TryCatchLevel > ec.LoopBeginTryCatchLevel)
+                               ec.ig.Emit (OpCodes.Leave, begin);
+                       else if (ec.TryCatchLevel < ec.LoopBeginTryCatchLevel)
+                               throw new Exception ("Should never happen");
+                       else
+                               ec.ig.Emit (OpCodes.Br, begin);
+                       return false;
+               }
+       }
+
+       // <summary>
+       //   This is used in the control flow analysis code to specify whether the
+       //   current code block may return to its enclosing block before reaching
+       //   its end.
+       // </summary>
+       public enum FlowReturns {
+               // It can never return.
+               NEVER,
+
+               // This means that the block contains a conditional return statement
+               // somewhere.
+               SOMETIMES,
+
+               // The code always returns, ie. there's an unconditional return / break
+               // statement in it.
+               ALWAYS,
+
+               // The code always throws an exception.
+               EXCEPTION,
+
+               // The current code block is unreachable.  This happens if it's immediately
+               // following a FlowReturns.ALWAYS block.
+               UNREACHABLE
+       }
+
+       // <summary>
+       //   This is a special bit vector which can inherit from another bit vector doing a
+       //   copy-on-write strategy.  The inherited vector may have a smaller size than the
+       //   current one.
+       // </summary>
+       public class MyBitVector {
+               public readonly int Count;
+               public readonly MyBitVector InheritsFrom;
+
+               bool is_dirty;
+               BitArray vector;
+
+               public MyBitVector (int Count)
+                       : this (null, Count)
+               { }
+
+               public MyBitVector (MyBitVector InheritsFrom, int Count)
+               {
+                       this.InheritsFrom = InheritsFrom;
+                       this.Count = Count;
+               }
+
+               // <summary>
+               //   Checks whether this bit vector has been modified.  After setting this to true,
+               //   we won't use the inherited vector anymore, but our own copy of it.
+               // </summary>
+               public bool IsDirty {
+                       get {
+                               return is_dirty;
+                       }
+
+                       set {
+                               if (!is_dirty)
+                                       initialize_vector ();
+                       }
+               }
+
+               // <summary>
+               //   Get/set bit `index' in the bit vector.
+               // </summary>
+               public bool this [int index]
+               {
+                       get {
+                               if (index > Count)
+                                       throw new ArgumentOutOfRangeException ();
+
+                               // We're doing a "copy-on-write" strategy here; as long
+                               // as nobody writes to the array, we can use our parent's
+                               // copy instead of duplicating the vector.
+
+                               if (vector != null)
+                                       return vector [index];
+                               else if (InheritsFrom != null) {
+                                       BitArray inherited = InheritsFrom.Vector;
+
+                                       if (index < inherited.Count)
+                                               return inherited [index];
+                                       else
+                                               return false;
+                               } else
+                                       return false;
+                       }
+
+                       set {
+                               if (index > Count)
+                                       throw new ArgumentOutOfRangeException ();
+
+                               // Only copy the vector if we're actually modifying it.
+
+                               if (this [index] != value) {
+                                       initialize_vector ();
+
+                                       vector [index] = value;
+                               }
+                       }
+               }
+
+               // <summary>
+               //   If you explicitly convert the MyBitVector to a BitArray, you will get a deep
+               //   copy of the bit vector.
+               // </summary>
+               public static explicit operator BitArray (MyBitVector vector)
+               {
+                       vector.initialize_vector ();
+                       return vector.Vector;
+               }
+
+               // <summary>
+               //   Performs an `or' operation on the bit vector.  The `new_vector' may have a
+               //   different size than the current one.
+               // </summary>
+               public void Or (MyBitVector new_vector)
+               {
+                       BitArray new_array = new_vector.Vector;
+
+                       initialize_vector ();
+
+                       int upper;
+                       if (vector.Count < new_array.Count)
+                               upper = vector.Count;
+                       else
+                               upper = new_array.Count;
+
+                       for (int i = 0; i < upper; i++)
+                               vector [i] = vector [i] | new_array [i];
+               }
+
+               // <summary>
+               //   Perfonrms an `and' operation on the bit vector.  The `new_vector' may have
+               //   a different size than the current one.
+               // </summary>
+               public void And (MyBitVector new_vector)
+               {
+                       BitArray new_array = new_vector.Vector;
+
+                       initialize_vector ();
+
+                       int lower, upper;
+                       if (vector.Count < new_array.Count)
+                               lower = upper = vector.Count;
+                       else {
+                               lower = new_array.Count;
+                               upper = vector.Count;
+                       }
+
+                       for (int i = 0; i < lower; i++)
+                               vector [i] = vector [i] & new_array [i];
+
+                       for (int i = lower; i < upper; i++)
+                               vector [i] = false;
+               }
+
+               // <summary>
+               //   This does a deep copy of the bit vector.
+               // </summary>
+               public MyBitVector Clone ()
+               {
+                       MyBitVector retval = new MyBitVector (Count);
+
+                       retval.Vector = Vector;
+
+                       return retval;
+               }
+
+               BitArray Vector {
+                       get {
+                               if (vector != null)
+                                       return vector;
+                               else if (!is_dirty && (InheritsFrom != null))
+                                       return InheritsFrom.Vector;
+
+                               initialize_vector ();
+
+                               return vector;
+                       }
+
+                       set {
+                               initialize_vector ();
+
+                               for (int i = 0; i < System.Math.Min (vector.Count, value.Count); i++)
+                                       vector [i] = value [i];
+                       }
+               }
+
+               void initialize_vector ()
+               {
+                       if (vector != null)
+                               return;
+
+                       vector = new BitArray (Count, false);
+                       if (InheritsFrom != null)
+                               Vector = InheritsFrom.Vector;
+
+                       is_dirty = true;
+               }
+
+               public override string ToString ()
+               {
+                       StringBuilder sb = new StringBuilder ("MyBitVector (");
+
+                       BitArray vector = Vector;
+                       sb.Append (Count);
+                       sb.Append (",");
+                       if (!IsDirty)
+                               sb.Append ("INHERITED - ");
+                       for (int i = 0; i < vector.Count; i++) {
+                               if (i > 0)
+                                       sb.Append (",");
+                               sb.Append (vector [i]);
+                       }
+                       
+                       sb.Append (")");
+                       return sb.ToString ();
+               }
+       }
+
+       // <summary>
+       //   The type of a FlowBranching.
+       // </summary>
+       public enum FlowBranchingType {
+               // Normal (conditional or toplevel) block.
+               BLOCK,
+
+               // A loop block.
+               LOOP_BLOCK,
+
+               // Try/Catch block.
+               EXCEPTION,
+
+               // Switch block.
+               SWITCH,
+
+               // Switch section.
+               SWITCH_SECTION
+       }
+
+       // <summary>
+       //   A new instance of this class is created every time a new block is resolved
+       //   and if there's branching in the block's control flow.
+       // </summary>
+       public class FlowBranching {
+               // <summary>
+               //   The type of this flow branching.
+               // </summary>
+               public readonly FlowBranchingType Type;
+
+               // <summary>
+               //   The block this branching is contained in.  This may be null if it's not
+               //   a top-level block and it doesn't declare any local variables.
+               // </summary>
+               public readonly Block Block;
+
+               // <summary>
+               //   The parent of this branching or null if this is the top-block.
+               // </summary>
+               public readonly FlowBranching Parent;
+
+               // <summary>
+               //   Start-Location of this flow branching.
+               // </summary>
+               public readonly Location Location;
+
+               // <summary>
+               //   A list of UsageVectors.  A new vector is added each time control flow may
+               //   take a different path.
+               // </summary>
+               public ArrayList Siblings;
+
+               // <summary>
+               //   If this is an infinite loop.
+               // </summary>
+               public bool Infinite;
+
+               // <summary>
+               //   If we may leave the current loop.
+               // </summary>
+               public bool MayLeaveLoop;
+
+               //
+               // Private
+               //
+               InternalParameters param_info;
+               int[] param_map;
+               MyStructInfo[] struct_params;
+               int num_params;
+               ArrayList finally_vectors;
+
+               static int next_id = 0;
+               int id;
+
+               // <summary>
+               //   Performs an `And' operation on the FlowReturns status
+               //   (for instance, a block only returns ALWAYS if all its siblings
+               //   always return).
+               // </summary>
+               public static FlowReturns AndFlowReturns (FlowReturns a, FlowReturns b)
+               {
+                       if (b == FlowReturns.UNREACHABLE)
+                               return a;
+
+                       switch (a) {
+                       case FlowReturns.NEVER:
+                               if (b == FlowReturns.NEVER)
+                                       return FlowReturns.NEVER;
+                               else
+                                       return FlowReturns.SOMETIMES;
+
+                       case FlowReturns.SOMETIMES:
+                               return FlowReturns.SOMETIMES;
+
+                       case FlowReturns.ALWAYS:
+                               if ((b == FlowReturns.ALWAYS) || (b == FlowReturns.EXCEPTION))
+                                       return FlowReturns.ALWAYS;
+                               else
+                                       return FlowReturns.SOMETIMES;
+
+                       case FlowReturns.EXCEPTION:
+                               if (b == FlowReturns.EXCEPTION)
+                                       return FlowReturns.EXCEPTION;
+                               else if (b == FlowReturns.ALWAYS)
+                                       return FlowReturns.ALWAYS;
+                               else
+                                       return FlowReturns.SOMETIMES;
+                       }
+
+                       return b;
+               }
+
+               // <summary>
+               //   The vector contains a BitArray with information about which local variables
+               //   and parameters are already initialized at the current code position.
+               // </summary>
+               public class UsageVector {
+                       // <summary>
+                       //   If this is true, then the usage vector has been modified and must be
+                       //   merged when we're done with this branching.
+                       // </summary>
+                       public bool IsDirty;
+
+                       // <summary>
+                       //   The number of parameters in this block.
+                       // </summary>
+                       public readonly int CountParameters;
+
+                       // <summary>
+                       //   The number of locals in this block.
+                       // </summary>
+                       public readonly int CountLocals;
+
+                       // <summary>
+                       //   If not null, then we inherit our state from this vector and do a
+                       //   copy-on-write.  If null, then we're the first sibling in a top-level
+                       //   block and inherit from the empty vector.
+                       // </summary>
+                       public readonly UsageVector InheritsFrom;
+
+                       //
+                       // Private.
+                       //
+                       MyBitVector locals, parameters;
+                       FlowReturns real_returns, real_breaks;
+                       bool is_finally;
+
+                       static int next_id = 0;
+                       int id;
+
+                       //
+                       // Normally, you should not use any of these constructors.
+                       //
+                       public UsageVector (UsageVector parent, int num_params, int num_locals)
+                       {
+                               this.InheritsFrom = parent;
+                               this.CountParameters = num_params;
+                               this.CountLocals = num_locals;
+                               this.real_returns = FlowReturns.NEVER;
+                               this.real_breaks = FlowReturns.NEVER;
+
+                               if (parent != null) {
+                                       locals = new MyBitVector (parent.locals, CountLocals);
+                                       if (num_params > 0)
+                                               parameters = new MyBitVector (parent.parameters, num_params);
+                                       real_returns = parent.Returns;
+                                       real_breaks = parent.Breaks;
+                               } else {
+                                       locals = new MyBitVector (null, CountLocals);
+                                       if (num_params > 0)
+                                               parameters = new MyBitVector (null, num_params);
+                               }
+
+                               id = ++next_id;
+                       }
+
+                       public UsageVector (UsageVector parent)
+                               : this (parent, parent.CountParameters, parent.CountLocals)
+                       { }
+
+                       // <summary>
+                       //   This does a deep copy of the usage vector.
+                       // </summary>
+                       public UsageVector Clone ()
+                       {
+                               UsageVector retval = new UsageVector (null, CountParameters, CountLocals);
+
+                               retval.locals = locals.Clone ();
+                               if (parameters != null)
+                                       retval.parameters = parameters.Clone ();
+                               retval.real_returns = real_returns;
+                               retval.real_breaks = real_breaks;
+
+                               return retval;
+                       }
+
+                       // 
+                       // State of parameter `number'.
+                       //
+                       public bool this [int number]
+                       {
+                               get {
+                                       if (number == -1)
+                                               return true;
+                                       else if (number == 0)
+                                               throw new ArgumentException ();
+
+                                       return parameters [number - 1];
+                               }
+
+                               set {
+                                       if (number == -1)
+                                               return;
+                                       else if (number == 0)
+                                               throw new ArgumentException ();
+
+                                       parameters [number - 1] = value;
+                               }
+                       }
+
+                       //
+                       // State of the local variable `vi'.
+                       // If the local variable is a struct, use a non-zero `field_idx'
+                       // to check an individual field in it.
+                       //
+                       public bool this [VariableInfo vi, int field_idx]
+                       {
+                               get {
+                                       if (vi.Number == -1)
+                                               return true;
+                                       else if (vi.Number == 0)
+                                               throw new ArgumentException ();
+
+                                       return locals [vi.Number + field_idx - 1];
+                               }
+
+                               set {
+                                       if (vi.Number == -1)
+                                               return;
+                                       else if (vi.Number == 0)
+                                               throw new ArgumentException ();
+
+                                       locals [vi.Number + field_idx - 1] = value;
+                               }
+                       }
+
+                       // <summary>
+                       //   Specifies when the current block returns.
+                       //   If this is FlowReturns.UNREACHABLE, then control can never reach the
+                       //   end of the method (so that we don't need to emit a return statement).
+                       //   The same applies for FlowReturns.EXCEPTION, but in this case the return
+                       //   value will never be used.
+                       // </summary>
+                       public FlowReturns Returns {
+                               get {
+                                       return real_returns;
+                               }
+
+                               set {
+                                       real_returns = value;
+                               }
+                       }
+
+                       // <summary>
+                       //   Specifies whether control may return to our containing block
+                       //   before reaching the end of this block.  This happens if there
+                       //   is a break/continue/goto/return in it.
+                       //   This can also be used to find out whether the statement immediately
+                       //   following the current block may be reached or not.
+                       // </summary>
+                       public FlowReturns Breaks {
+                               get {
+                                       return real_breaks;
+                               }
+
+                               set {
+                                       real_breaks = value;
+                               }
+                       }
+
+                       public bool AlwaysBreaks {
+                               get {
+                                       return (Breaks == FlowReturns.ALWAYS) ||
+                                               (Breaks == FlowReturns.EXCEPTION) ||
+                                               (Breaks == FlowReturns.UNREACHABLE);
+                               }
+                       }
+
+                       public bool MayBreak {
+                               get {
+                                       return Breaks != FlowReturns.NEVER;
+                               }
+                       }
+
+                       public bool AlwaysReturns {
+                               get {
+                                       return (Returns == FlowReturns.ALWAYS) ||
+                                               (Returns == FlowReturns.EXCEPTION);
+                               }
+                       }
+
+                       public bool MayReturn {
+                               get {
+                                       return (Returns == FlowReturns.SOMETIMES) ||
+                                               (Returns == FlowReturns.ALWAYS);
+                               }
+                       }
+
+                       // <summary>
+                       //   Merge a child branching.
+                       // </summary>
+                       public FlowReturns MergeChildren (FlowBranching branching, ICollection children)
+                       {
+                               MyBitVector new_locals = null;
+                               MyBitVector new_params = null;
+
+                               FlowReturns new_returns = FlowReturns.NEVER;
+                               FlowReturns new_breaks = FlowReturns.NEVER;
+                               bool new_returns_set = false, new_breaks_set = false;
+
+                               Report.Debug (2, "MERGING CHILDREN", branching, branching.Type,
+                                             this, children.Count);
+
+                               foreach (UsageVector child in children) {
+                                       Report.Debug (2, "  MERGING CHILD", child, child.is_finally);
+                                       
+                                       if (!child.is_finally) {
+                                               if (child.Breaks != FlowReturns.UNREACHABLE) {
+                                                       // If Returns is already set, perform an
+                                                       // `And' operation on it, otherwise just set just.
+                                                       if (!new_returns_set) {
+                                                               new_returns = child.Returns;
+                                                               new_returns_set = true;
+                                                       } else
+                                                               new_returns = AndFlowReturns (
+                                                                       new_returns, child.Returns);
+                                               }
+
+                                               // If Breaks is already set, perform an
+                                               // `And' operation on it, otherwise just set just.
+                                               if (!new_breaks_set) {
+                                                       new_breaks = child.Breaks;
+                                                       new_breaks_set = true;
+                                               } else
+                                                       new_breaks = AndFlowReturns (
+                                                               new_breaks, child.Breaks);
+                                       }
+
+                                       // Ignore unreachable children.
+                                       if (child.Returns == FlowReturns.UNREACHABLE)
+                                               continue;
+
+                                       // A local variable is initialized after a flow branching if it
+                                       // has been initialized in all its branches which do neither
+                                       // always return or always throw an exception.
+                                       //
+                                       // If a branch may return, but does not always return, then we
+                                       // can treat it like a never-returning branch here: control will
+                                       // only reach the code position after the branching if we did not
+                                       // return here.
+                                       //
+                                       // It's important to distinguish between always and sometimes
+                                       // returning branches here:
+                                       //
+                                       //    1   int a;
+                                       //    2   if (something) {
+                                       //    3      return;
+                                       //    4      a = 5;
+                                       //    5   }
+                                       //    6   Console.WriteLine (a);
+                                       //
+                                       // The if block in lines 3-4 always returns, so we must not look
+                                       // at the initialization of `a' in line 4 - thus it'll still be
+                                       // uninitialized in line 6.
+                                       //
+                                       // On the other hand, the following is allowed:
+                                       //
+                                       //    1   int a;
+                                       //    2   if (something)
+                                       //    3      a = 5;
+                                       //    4   else
+                                       //    5      return;
+                                       //    6   Console.WriteLine (a);
+                                       //
+                                       // Here, `a' is initialized in line 3 and we must not look at
+                                       // line 5 since it always returns.
+                                       // 
+                                       if (child.is_finally) {
+                                               if (new_locals == null)
+                                                       new_locals = locals.Clone ();
+                                               new_locals.Or (child.locals);
+
+                                               if (parameters != null) {
+                                                       if (new_params == null)
+                                                               new_params = parameters.Clone ();
+                                                       new_params.Or (child.parameters);
+                                               }
+
+                                       } else {
+                                               if (!child.AlwaysReturns && !child.AlwaysBreaks) {
+                                                       if (new_locals != null)
+                                                               new_locals.And (child.locals);
+                                                       else {
+                                                               new_locals = locals.Clone ();
+                                                               new_locals.Or (child.locals);
+                                                       }
+                                               } else if (children.Count == 1) {
+                                                       new_locals = locals.Clone ();
+                                                       new_locals.Or (child.locals);
+                                               }
+
+                                               // An `out' parameter must be assigned in all branches which do
+                                               // not always throw an exception.
+                                               if (parameters != null) {
+                                                       if (child.Breaks != FlowReturns.EXCEPTION) {
+                                                               if (new_params != null)
+                                                                       new_params.And (child.parameters);
+                                                               else {
+                                                                       new_params = parameters.Clone ();
+                                                                       new_params.Or (child.parameters);
+                                                               }
+                                                       } else if (children.Count == 1) {
+                                                               new_params = parameters.Clone ();
+                                                               new_params.Or (child.parameters);
+                                                       }
+                                               }
+                                       }
+                               }
+
+                               Returns = new_returns;
+                               if ((branching.Type == FlowBranchingType.BLOCK) ||
+                                   (branching.Type == FlowBranchingType.EXCEPTION) ||
+                                   (new_breaks == FlowReturns.UNREACHABLE) ||
+                                   (new_breaks == FlowReturns.EXCEPTION))
+                                       Breaks = new_breaks;
+                               else if (branching.Type == FlowBranchingType.SWITCH_SECTION)
+                                       Breaks = new_returns;
+                               else if (branching.Type == FlowBranchingType.SWITCH){
+                                       if (new_breaks == FlowReturns.ALWAYS)
+                                               Breaks = FlowReturns.ALWAYS;
+                               }
+
+                               //
+                               // We've now either reached the point after the branching or we will
+                               // never get there since we always return or always throw an exception.
+                               //
+                               // If we can reach the point after the branching, mark all locals and
+                               // parameters as initialized which have been initialized in all branches
+                               // we need to look at (see above).
+                               //
+
+                               if (((new_breaks != FlowReturns.ALWAYS) &&
+                                    (new_breaks != FlowReturns.EXCEPTION) &&
+                                    (new_breaks != FlowReturns.UNREACHABLE)) ||
+                                   (children.Count == 1)) {
+                                       if (new_locals != null)
+                                               locals.Or (new_locals);
+
+                                       if (new_params != null)
+                                               parameters.Or (new_params);
+                               }
+
+                               Report.Debug (2, "MERGING CHILDREN DONE", branching.Type,
+                                             new_params, new_locals, new_returns, new_breaks,
+                                             branching.Infinite, branching.MayLeaveLoop, this);
+
+                               if (branching.Type == FlowBranchingType.SWITCH_SECTION) {
+                                       if ((new_breaks != FlowReturns.ALWAYS) &&
+                                           (new_breaks != FlowReturns.EXCEPTION) &&
+                                           (new_breaks != FlowReturns.UNREACHABLE))
+                                               Report.Error (163, branching.Location,
+                                                             "Control cannot fall through from one " +
+                                                             "case label to another");
+                               }
+
+                               if (branching.Infinite && !branching.MayLeaveLoop) {
+                                       Report.Debug (1, "INFINITE", new_returns, new_breaks,
+                                                     Returns, Breaks, this);
+
+                                       // We're actually infinite.
+                                       if (new_returns == FlowReturns.NEVER) {
+                                               Breaks = FlowReturns.UNREACHABLE;
+                                               return FlowReturns.UNREACHABLE;
+                                       }
+
+                                       // If we're an infinite loop and do not break, the code after
+                                       // the loop can never be reached.  However, if we may return
+                                       // from the loop, then we do always return (or stay in the loop
+                                       // forever).
+                                       if ((new_returns == FlowReturns.SOMETIMES) ||
+                                           (new_returns == FlowReturns.ALWAYS)) {
+                                               Returns = FlowReturns.ALWAYS;
+                                               return FlowReturns.ALWAYS;
+                                       }
+                               }
+
+                               return new_returns;
+                       }
+
+                       // <summary>
+                       //   Tells control flow analysis that the current code position may be reached with
+                       //   a forward jump from any of the origins listed in `origin_vectors' which is a
+                       //   list of UsageVectors.
+                       //
+                       //   This is used when resolving forward gotos - in the following example, the
+                       //   variable `a' is uninitialized in line 8 becase this line may be reached via
+                       //   the goto in line 4:
+                       //
+                       //      1     int a;
+                       //
+                       //      3     if (something)
+                       //      4        goto World;
+                       //
+                       //      6     a = 5;
+                       //
+                       //      7  World:
+                       //      8     Console.WriteLine (a);
+                       //
+                       // </summary>
+                       public void MergeJumpOrigins (ICollection origin_vectors)
+                       {
+                               Report.Debug (1, "MERGING JUMP ORIGIN", this);
+
+                               real_breaks = FlowReturns.NEVER;
+                               real_returns = FlowReturns.NEVER;
+
+                               foreach (UsageVector vector in origin_vectors) {
+                                       Report.Debug (1, "  MERGING JUMP ORIGIN", vector);
+
+                                       locals.And (vector.locals);
+                                       if (parameters != null)
+                                               parameters.And (vector.parameters);
+                                       Breaks = AndFlowReturns (Breaks, vector.Breaks);
+                                       Returns = AndFlowReturns (Returns, vector.Returns);
+                               }
+
+                               Report.Debug (1, "MERGING JUMP ORIGIN DONE", this);
+                       }
+
+                       // <summary>
+                       //   This is used at the beginning of a finally block if there were
+                       //   any return statements in the try block or one of the catch blocks.
+                       // </summary>
+                       public void MergeFinallyOrigins (ICollection finally_vectors)
+                       {
+                               Report.Debug (1, "MERGING FINALLY ORIGIN", this);
+
+                               real_breaks = FlowReturns.NEVER;
+
+                               foreach (UsageVector vector in finally_vectors) {
+                                       Report.Debug (1, "  MERGING FINALLY ORIGIN", vector);
+
+                                       if (parameters != null)
+                                               parameters.And (vector.parameters);
+                                       Breaks = AndFlowReturns (Breaks, vector.Breaks);
+                               }
+
+                               is_finally = true;
+
+                               Report.Debug (1, "MERGING FINALLY ORIGIN DONE", this);
+                       }
+                       // <summary>
+                       //   Performs an `or' operation on the locals and the parameters.
+                       // </summary>
+                       public void Or (UsageVector new_vector)
+                       {
+                               locals.Or (new_vector.locals);
+                               if (parameters != null)
+                                       parameters.Or (new_vector.parameters);
+                       }
+
+                       // <summary>
+                       //   Performs an `and' operation on the locals.
+                       // </summary>
+                       public void AndLocals (UsageVector new_vector)
+                       {
+                               locals.And (new_vector.locals);
+                       }
+
+                       // <summary>
+                       //   Returns a deep copy of the parameters.
+                       // </summary>
+                       public MyBitVector Parameters {
+                               get {
+                                       if (parameters != null)
+                                               return parameters.Clone ();
+                                       else
+                                               return null;
+                               }
+                       }
+
+                       // <summary>
+                       //   Returns a deep copy of the locals.
+                       // </summary>
+                       public MyBitVector Locals {
+                               get {
+                                       return locals.Clone ();
+                               }
+                       }
+
+                       //
+                       // Debugging stuff.
+                       //
+
+                       public override string ToString ()
+                       {
+                               StringBuilder sb = new StringBuilder ();
+
+                               sb.Append ("Vector (");
+                               sb.Append (id);
+                               sb.Append (",");
+                               sb.Append (Returns);
+                               sb.Append (",");
+                               sb.Append (Breaks);
+                               if (parameters != null) {
+                                       sb.Append (" - ");
+                                       sb.Append (parameters);
+                               }
+                               sb.Append (" - ");
+                               sb.Append (locals);
+                               sb.Append (")");
+
+                               return sb.ToString ();
+                       }
+               }
+
+               FlowBranching (FlowBranchingType type, Location loc)
+               {
+                       this.Siblings = new ArrayList ();
+                       this.Block = null;
+                       this.Location = loc;
+                       this.Type = type;
+                       id = ++next_id;
+               }
+
+               // <summary>
+               //   Creates a new flow branching for `block'.
+               //   This is used from Block.Resolve to create the top-level branching of
+               //   the block.
+               // </summary>
+               public FlowBranching (Block block, InternalParameters ip, Location loc)
+                       : this (FlowBranchingType.BLOCK, loc)
+               {
+                       Block = block;
+                       Parent = null;
+
+                       int count = (ip != null) ? ip.Count : 0;
+
+                       param_info = ip;
+                       param_map = new int [count];
+                       struct_params = new MyStructInfo [count];
+                       num_params = 0;
+
+                       for (int i = 0; i < count; i++) {
+                               //Parameter.Modifier mod = param_info.ParameterModifier (i);
+
+                       //      if ((mod & Parameter.Modifier.OUT) == 0)
+                       //              continue;
+
+                               param_map [i] = ++num_params;
+
+                               Type param_type = param_info.ParameterType (i);
+
+                               struct_params [i] = MyStructInfo.GetStructInfo (param_type);
+                               if (struct_params [i] != null)
+                                       num_params += struct_params [i].Count;
+                       }
+
+                       Siblings = new ArrayList ();
+                       Siblings.Add (new UsageVector (null, num_params, block.CountVariables));
+               }
+
+               // <summary>
+               //   Creates a new flow branching which is contained in `parent'.
+               //   You should only pass non-null for the `block' argument if this block
+               //   introduces any new variables - in this case, we need to create a new
+               //   usage vector with a different size than our parent's one.
+               // </summary>
+               public FlowBranching (FlowBranching parent, FlowBranchingType type,
+                                     Block block, Location loc)
+                       : this (type, loc)
+               {
+                       Parent = parent;
+                       Block = block;
+
+                       if (parent != null) {
+                               param_info = parent.param_info;
+                               param_map = parent.param_map;
+                               struct_params = parent.struct_params;
+                               num_params = parent.num_params;
+                       }
+
+                       UsageVector vector;
+                       if (Block != null)
+                               vector = new UsageVector (parent.CurrentUsageVector, num_params,
+                                                         Block.CountVariables);
+                       else
+                               vector = new UsageVector (Parent.CurrentUsageVector);
+
+                       Siblings.Add (vector);
+
+                       switch (Type) {
+                       case FlowBranchingType.EXCEPTION:
+                               finally_vectors = new ArrayList ();
+                               break;
+
+                       default:
+                               break;
+                       }
+               }
+
+               // <summary>
+               //   Returns the branching's current usage vector.
+               // </summary>
+               public UsageVector CurrentUsageVector
+               {
+                       get {
+                               return (UsageVector) Siblings [Siblings.Count - 1];
+                       }
+               }
+
+               // <summary>
+               //   Creates a sibling of the current usage vector.
+               // </summary>
+               public void CreateSibling ()
+               {
+                       Siblings.Add (new UsageVector (Parent.CurrentUsageVector));
+
+                       Report.Debug (1, "CREATED SIBLING", CurrentUsageVector);
+               }
+
+               // <summary>
+               //   Creates a sibling for a `finally' block.
+               // </summary>
+               public void CreateSiblingForFinally ()
+               {
+                       if (Type != FlowBranchingType.EXCEPTION)
+                               throw new NotSupportedException ();
+
+                       CreateSibling ();
+
+                       CurrentUsageVector.MergeFinallyOrigins (finally_vectors);
+               }
+
+
+               // <summary>
+               //   Merge a child branching.
+               // </summary>
+               public FlowReturns MergeChild (FlowBranching child)
+               {
+                       FlowReturns returns = CurrentUsageVector.MergeChildren (child, child.Siblings);
+
+                       if (child.Type != FlowBranchingType.LOOP_BLOCK)
+                               MayLeaveLoop |= child.MayLeaveLoop;
+                       else
+                               MayLeaveLoop = false;
+
+                       return returns;
+               }
+               // <summary>
+               //   Does the toplevel merging.
+               // </summary>
+               public FlowReturns MergeTopBlock ()
+               {
+                       if ((Type != FlowBranchingType.BLOCK) || (Block == null))
+                               throw new NotSupportedException ();
+
+                       UsageVector vector = new UsageVector (null, num_params, Block.CountVariables);
+
+                       Report.Debug (1, "MERGING TOP BLOCK", Location, vector);
+
+                       vector.MergeChildren (this, Siblings);
+
+                       Siblings.Clear ();
+                       Siblings.Add (vector);
+
+                       Report.Debug (1, "MERGING TOP BLOCK DONE", Location, vector);
+
+                       if (vector.Breaks != FlowReturns.EXCEPTION) {
+                               return vector.AlwaysBreaks ? FlowReturns.ALWAYS : vector.Returns;
+                       } else
+                               return FlowReturns.EXCEPTION;
+               }
+
+               public bool InTryBlock ()
+               {
+                       if (finally_vectors != null)
+                               return true;
+                       else if (Parent != null)
+                               return Parent.InTryBlock ();
+                       else
+                               return false;
+               }
+
+               public void AddFinallyVector (UsageVector vector)
+               {
+                       if (finally_vectors != null) {
+                               finally_vectors.Add (vector.Clone ());
+                               return;
+                       }
+
+                       if (Parent != null)
+                               Parent.AddFinallyVector (vector);
+                       else
+                               throw new NotSupportedException ();
+               }
+
+               public bool IsVariableAssigned (VariableInfo vi)
+               {
+                       if (CurrentUsageVector.AlwaysBreaks)
+                               return true;
+                       else
+                               return CurrentUsageVector [vi, 0];
+               }
+
+               public bool IsVariableAssigned (VariableInfo vi, int field_idx)
+               {
+                       if (CurrentUsageVector.AlwaysBreaks)
+                               return true;
+                       else
+                               return CurrentUsageVector [vi, field_idx];
+               }
+
+               public void SetVariableAssigned (VariableInfo vi)
+               {
+                       if (CurrentUsageVector.AlwaysBreaks)
+                               return;
+
+                       CurrentUsageVector [vi, 0] = true;
+               }
+
+               public void SetVariableAssigned (VariableInfo vi, int field_idx)
+               {
+                       if (CurrentUsageVector.AlwaysBreaks)
+                               return;
+
+                       CurrentUsageVector [vi, field_idx] = true;
+               }
+
+               public bool IsParameterAssigned (int number)
+               {
+                       int index = param_map [number];
+
+                       if (index == 0)
+                               return true;
+
+                       if (CurrentUsageVector [index])
+                               return true;
+
+                       // Parameter is not assigned, so check whether it's a struct.
+                       // If it's either not a struct or a struct which non-public
+                       // fields, return false.
+                       MyStructInfo struct_info = struct_params [number];
+                       if ((struct_info == null) || struct_info.HasNonPublicFields)
+                               return false;
+
+                       // Ok, so each field must be assigned.
+                       for (int i = 0; i < struct_info.Count; i++)
+                               if (!CurrentUsageVector [index + i])
+                                       return false;
+
+                       return true;
+               }
+
+               public bool IsParameterAssigned (int number, string field_name)
+               {
+                       int index = param_map [number];
+
+                       if (index == 0)
+                               return true;
+
+                       MyStructInfo info = (MyStructInfo) struct_params [number];
+                       if (info == null)
+                               return true;
+
+                       int field_idx = info [field_name];
+
+                       return CurrentUsageVector [index + field_idx];
+               }
+
+               public void SetParameterAssigned (int number)
+               {
+                       if (param_map [number] == 0)
+                               return;
+
+                       if (!CurrentUsageVector.AlwaysBreaks)
+                               CurrentUsageVector [param_map [number]] = true;
+               }
+
+               public void SetParameterAssigned (int number, string field_name)
+               {
+                       int index = param_map [number];
+
+                       if (index == 0)
+                               return;
+
+                       MyStructInfo info = (MyStructInfo) struct_params [number];
+                       if (info == null)
+                               return;
+
+                       int field_idx = info [field_name];
+
+                       if (!CurrentUsageVector.AlwaysBreaks)
+                               CurrentUsageVector [index + field_idx] = true;
+               }
+
+               public bool IsReachable ()
+               {
+                       bool reachable;
+
+                       switch (Type) {
+                       case FlowBranchingType.SWITCH_SECTION:
+                               // The code following a switch block is reachable unless the switch
+                               // block always returns.
+                               reachable = !CurrentUsageVector.AlwaysReturns;
+                               break;
+
+                       case FlowBranchingType.LOOP_BLOCK:
+                               // The code following a loop is reachable unless the loop always
+                               // returns or it's an infinite loop without any `break's in it.
+                               reachable = !CurrentUsageVector.AlwaysReturns &&
+                                       (CurrentUsageVector.Breaks != FlowReturns.UNREACHABLE);
+                               break;
+
+                       default:
+                               // The code following a block or exception is reachable unless the
+                               // block either always returns or always breaks.
+                               reachable = !CurrentUsageVector.AlwaysBreaks &&
+                                       !CurrentUsageVector.AlwaysReturns;
+                               break;
+                       }
+
+                       Report.Debug (1, "REACHABLE", Type, CurrentUsageVector.Returns,
+                                     CurrentUsageVector.Breaks, CurrentUsageVector, reachable);
+
+                       return reachable;
+               }
+
+               public override string ToString ()
+               {
+                       StringBuilder sb = new StringBuilder ("FlowBranching (");
+
+                       sb.Append (id);
+                       sb.Append (",");
+                       sb.Append (Type);
+                       if (Block != null) {
+                               sb.Append (" - ");
+                               sb.Append (Block.ID);
+                               sb.Append (" - ");
+                               sb.Append (Block.StartLocation);
+                       }
+                       sb.Append (" - ");
+                       sb.Append (Siblings.Count);
+                       sb.Append (" - ");
+                       sb.Append (CurrentUsageVector);
+                       sb.Append (")");
+                       return sb.ToString ();
+               }
+       }
+
+       public class MyStructInfo {
+               public readonly Type Type;
+               public readonly FieldInfo[] Fields;
+               public readonly FieldInfo[] NonPublicFields;
+               public readonly int Count;
+               public readonly int CountNonPublic;
+               public readonly bool HasNonPublicFields;
+
+               private static Hashtable field_type_hash = new Hashtable ();
+               private Hashtable field_hash;
+
+               // Private constructor.  To save memory usage, we only need to create one instance
+               // of this class per struct type.
+               private MyStructInfo (Type type)
+               {
+                       this.Type = type;
+
+                       if (type is TypeBuilder) {
+                               TypeContainer tc = TypeManager.LookupTypeContainer (type);
+
+                               ArrayList fields = tc.Fields;
+                               if (fields != null) {
+                                       foreach (Field field in fields) {
+                                               if ((field.ModFlags & Modifiers.STATIC) != 0)
+                                                       continue;
+                                               if ((field.ModFlags & Modifiers.PUBLIC) != 0)
+                                                       ++Count;
+                                               else
+                                                       ++CountNonPublic;
+                                       }
+                               }
+
+                               Fields = new FieldInfo [Count];
+                               NonPublicFields = new FieldInfo [CountNonPublic];
+
+                               Count = CountNonPublic = 0;
+                               if (fields != null) {
+                                       foreach (Field field in fields) {
+                                               if ((field.ModFlags & Modifiers.STATIC) != 0)
+                                                       continue;
+                                               if ((field.ModFlags & Modifiers.PUBLIC) != 0)
+                                                       Fields [Count++] = field.FieldBuilder;
+                                               else
+                                                       NonPublicFields [CountNonPublic++] =
+                                                               field.FieldBuilder;
+                                       }
+                               }
+                               
+                       } else {
+                               Fields = type.GetFields (BindingFlags.Instance|BindingFlags.Public);
+                               Count = Fields.Length;
+
+                               NonPublicFields = type.GetFields (BindingFlags.Instance|BindingFlags.NonPublic);
+                               CountNonPublic = NonPublicFields.Length;
+                       }
+
+                       Count += NonPublicFields.Length;
+
+                       int number = 0;
+                       field_hash = new Hashtable ();
+                       foreach (FieldInfo field in Fields)
+                               field_hash.Add (field.Name, ++number);
+
+                       if (NonPublicFields.Length != 0)
+                               HasNonPublicFields = true;
+
+                       foreach (FieldInfo field in NonPublicFields)
+                               field_hash.Add (field.Name, ++number);
+               }
 
-       /// <summary>
-       ///   `goto case' statement
-       /// </summary>
-       public class GotoCase : Statement {
-               Expression expr;
-               
-               public GotoCase (Expression e, Location l)
-               {
-                       expr = e;
-                       loc = l;
+               public int this [string name] {
+                       get {
+                               if (field_hash.Contains (name))
+                                       return (int) field_hash [name];
+                               else
+                                       return 0;
+                       }
                }
 
-               public override bool Emit (EmitContext ec)
-               {
-                       if (ec.Switch == null){
-                               Report.Error (153, loc, "goto case is only valid in a switch statement");
-                               return false;
+               public FieldInfo this [int index] {
+                       get {
+                               if (index >= Fields.Length)
+                                       return NonPublicFields [index - Fields.Length];
+                               else
+                                       return Fields [index];
                        }
+               }                      
 
-                       expr = expr.Resolve (ec);
-                       if (expr == null)
-                               return false;
+               public static MyStructInfo GetStructInfo (Type type)
+               {
+                       if (!TypeManager.IsValueType (type) || TypeManager.IsEnumType (type))
+                               return null;
 
-                       if (!(expr is Constant)){
-                               Report.Error (159, loc, "Target expression for goto case is not constant");
-                               return false;
-                       }
+                       if (!(type is TypeBuilder) && TypeManager.IsBuiltinType (type))
+                               return null;
 
-                       object val = Expression.ConvertIntLiteral (
-                               (Constant) expr, ec.Switch.SwitchType, loc);
+                       MyStructInfo info = (MyStructInfo) field_type_hash [type];
+                       if (info != null)
+                               return info;
 
-                       if (val == null)
-                               return false;
-                                       
-                       SwitchLabel sl = (SwitchLabel) ec.Switch.Elements [val];
+                       info = new MyStructInfo (type);
+                       field_type_hash.Add (type, info);
+                       return info;
+               }
 
-                       if (sl == null){
-                               Report.Error (
-                                       159, loc,
-                                       "No such label 'case " + val + "': for the goto case");
-                       }
+               public static MyStructInfo GetStructInfo (TypeContainer tc)
+               {
+                       MyStructInfo info = (MyStructInfo) field_type_hash [tc.TypeBuilder];
+                       if (info != null)
+                               return info;
 
-                       ec.ig.Emit (OpCodes.Br, sl.ILLabelCode);
-                       return true;
+                       info = new MyStructInfo (tc.TypeBuilder);
+                       field_type_hash.Add (tc.TypeBuilder, info);
+                       return info;
                }
        }
        
-       public class Throw : Statement {
-               Expression expr;
+       public class VariableInfo : IVariable {
+               public Expression Type;
+               public LocalBuilder LocalBuilder;
+               public Type VariableType;
+               public readonly string Name;
+               public readonly Location Location;
+               public readonly int Block;
+
+               public int Number;
                
-               public Throw (Expression expr, Location l)
+               public bool Used;
+               public bool Assigned;
+               public bool ReadOnly;
+               
+               public VariableInfo (Expression type, string name, int block, Location l)
                {
-                       this.expr = expr;
-                       loc = l;
+                       Type = type;
+                       Name = name;
+                       Block = block;
+                       LocalBuilder = null;
+                       Location = l;
                }
 
-               public override bool Resolve (EmitContext ec)
+               public VariableInfo (TypeContainer tc, int block, Location l)
                {
-                       if (expr != null){
-                               expr = expr.Resolve (ec);
-                               if (expr == null)
-                                       return false;
+                       VariableType = tc.TypeBuilder;
+                       struct_info = MyStructInfo.GetStructInfo (tc);
+                       Block = block;
+                       LocalBuilder = null;
+                       Location = l;
+               }
+
+               MyStructInfo struct_info;
+               public MyStructInfo StructInfo {
+                       get {
+                               return struct_info;
                        }
-                       return true;
                }
-                       
-               public override bool Emit (EmitContext ec)
-               {
-                       if (expr == null){
-                               if (ec.InCatch)
-                                       ec.ig.Emit (OpCodes.Rethrow);
-                               else {
-                                       Report.Error (
-                                               156, loc,
-                                               "A throw statement with no argument is only " +
-                                               "allowed in a catch clause");
-                               }
+
+               public bool IsAssigned (EmitContext ec, Location loc)
+               {/* FIXME: we shouldn't just skip this!!!
+                       if (!ec.DoFlowAnalysis || ec.CurrentBranching.IsVariableAssigned (this))
+                               return true;
+
+                       MyStructInfo struct_info = StructInfo;
+                       if ((struct_info == null) || (struct_info.HasNonPublicFields && (Name != null))) {
+                               Report.Error (165, loc, "Use of unassigned local variable `" + Name + "'");
+                               ec.CurrentBranching.SetVariableAssigned (this);
                                return false;
                        }
-                       
-                       expr.Emit (ec);
 
-                       ec.ig.Emit (OpCodes.Throw);
+                       int count = struct_info.Count;
+
+                       for (int i = 0; i < count; i++) {
+                               if (!ec.CurrentBranching.IsVariableAssigned (this, i+1)) {
+                                       if (Name != null) {
+                                               Report.Error (165, loc,
+                                                             "Use of unassigned local variable `" +
+                                                             Name + "'");
+                                               ec.CurrentBranching.SetVariableAssigned (this);
+                                               return false;
+                                       }
 
+                                       FieldInfo field = struct_info [i];
+                                       Report.Error (171, loc,
+                                                     "Field `" + TypeManager.MonoBASIC_Name (VariableType) +
+                                                     "." + field.Name + "' must be fully initialized " +
+                                                     "before control leaves the constructor");
+                                       return false;
+                               }
+                       }
+*/
                        return true;
                }
-       }
 
-       public class Break : Statement {
-               
-               public Break (Location l)
+               public bool IsFieldAssigned (EmitContext ec, string name, Location loc)
                {
-                       loc = l;
-               }
+                       if (!ec.DoFlowAnalysis || ec.CurrentBranching.IsVariableAssigned (this) ||
+                           (struct_info == null))
+                               return true;
 
-               public override bool Emit (EmitContext ec)
-               {
-                       ILGenerator ig = ec.ig;
+                       int field_idx = StructInfo [name];
+                       if (field_idx == 0)
+                               return true;
 
-                       if (ec.InLoop == false && ec.Switch == null){
-                               Report.Error (139, loc, "No enclosing loop or switch to continue to");
+                       if (!ec.CurrentBranching.IsVariableAssigned (this, field_idx)) {
+                               Report.Error (170, loc,
+                                             "Use of possibly unassigned field `" + name + "'");
+                               ec.CurrentBranching.SetVariableAssigned (this, field_idx);
                                return false;
                        }
 
-                       ec.Breaks = true;
-                       if (ec.InTry || ec.InCatch)
-                               ig.Emit (OpCodes.Leave, ec.LoopEnd);
-                       else
-                               ig.Emit (OpCodes.Br, ec.LoopEnd);
+                       return true;
+               }
 
-                       return false;
+               public void SetAssigned (EmitContext ec)
+               {
+                       if (ec.DoFlowAnalysis)
+                               ec.CurrentBranching.SetVariableAssigned (this);
                }
-       }
 
-       public class Continue : Statement {
-               
-               public Continue (Location l)
+               public void SetFieldAssigned (EmitContext ec, string name)
                {
-                       loc = l;
+                       if (ec.DoFlowAnalysis && (struct_info != null))
+                               ec.CurrentBranching.SetVariableAssigned (this, StructInfo [name]);
                }
 
-               public override bool Emit (EmitContext ec)
+               public bool Resolve (DeclSpace decl)
                {
-                       Label begin = ec.LoopBegin;
-                       
-                       if (!ec.InLoop){
-                               Report.Error (139, loc, "No enclosing loop to continue to");
+                       if (struct_info != null)
+                               return true;
+
+                       if (VariableType == null)
+                               VariableType = decl.ResolveType (Type, false, Location);
+
+                       if (VariableType == null)
                                return false;
-                       } 
 
-                       //
-                       // UGH: Non trivial.  This Br might cross a try/catch boundary
-                       // How can we tell?
-                       //
-                       // while () {
-                       //   try { ... } catch { continue; }
-                       // }
-                       //
-                       // From:
-                       // try {} catch { while () { continue; }}
-                       //
-                       ec.ig.Emit (OpCodes.Br, begin);
-                       return false;
-               }
-       }
-       
-       public class VariableInfo {
-               public readonly string Type;
-               public LocalBuilder LocalBuilder;
-               public Type VariableType;
-               public readonly Location Location;
-               
-               public bool Used;
-               public bool Assigned;
-               public bool ReadOnly;
-               
-               public VariableInfo (string type, Location l)
-               {
-                       Type = type;
-                       LocalBuilder = null;
-                       Location = l;
+                       struct_info = MyStructInfo.GetStructInfo (VariableType);
+
+                       return true;
                }
 
                public void MakePinned ()
                {
                        TypeManager.MakePinned (LocalBuilder);
-               }                               
+               }
+
+               public override string ToString ()
+               {
+                       return "VariableInfo (" + Number + "," + Type + "," + Location + ")";
+               }
        }
                
        /// <summary>
@@ -841,7 +2789,7 @@ namespace Mono.CSharp {
                //
                // The statements in this block
                //
-               ArrayList statements;
+               public ArrayList statements;
 
                //
                // An array of Blocks.  We keep track of children just
@@ -855,21 +2803,28 @@ namespace Mono.CSharp {
                //
                // Labels.  (label, block) pairs.
                //
-               Hashtable labels;
+               CaseInsensitiveHashtable labels;
 
                //
                // Keeps track of (name, type) pairs
                //
-               Hashtable variables;
+               CaseInsensitiveHashtable variables;
 
                //
                // Keeps track of constants
-               Hashtable constants;
+               CaseInsensitiveHashtable constants;
 
                //
                // Maps variable names to ILGenerator.LocalBuilders
                //
-               Hashtable local_builders;
+               //CaseInsensitiveHashtable local_builders;
+
+               // to hold names of variables required for late binding
+               public const string lateBindingArgs = "1_LBArgs";
+               public const string lateBindingArgNames = "1_LBArgsNames";
+               public const string lateBindingCopyBack = "1_LBCopyBack";
+
+               bool isLateBindingRequired = false;
 
                bool used = false;
 
@@ -885,17 +2840,47 @@ namespace Mono.CSharp {
                        : this (parent, implicit_block, Location.Null, Location.Null)
                { }
 
+               public Block (Block parent, bool implicit_block, Parameters parameters)
+                       : this (parent, implicit_block, parameters, Location.Null, Location.Null)
+               { }
+
                public Block (Block parent, Location start, Location end)
                        : this (parent, false, start, end)
                { }
 
+               public Block (Block parent, Parameters parameters, Location start, Location end)
+                       : this (parent, false, parameters, start, end)
+               { }
+
                public Block (Block parent, bool implicit_block, Location start, Location end)
+                       : this (parent, implicit_block, Parameters.EmptyReadOnlyParameters,
+                               start, end)
+               { }
+
+               public Block (Block parent, bool implicit_block, Parameters parameters,
+                             Location start, Location end)
                {
                        if (parent != null)
                                parent.AddChild (this);
+                       else {
+                               // Top block
+                               // Add variables that may be required for late binding
+                               variables = new CaseInsensitiveHashtable ();
+                               ArrayList rank_specifier = new ArrayList ();
+                               ArrayList element = new ArrayList ();
+                               element.Add (new EmptyExpression ());
+                               rank_specifier.Add (element);
+                               Expression e = Mono.MonoBASIC.Parser.DecomposeQI ("System.Object[]", start);
+                               AddVariable (e, Block.lateBindingArgs, null, start);
+                               e = Mono.MonoBASIC.Parser.DecomposeQI ("System.String[]", start);
+                               AddVariable (e, Block.lateBindingArgNames, null, start);
+                               e = Mono.MonoBASIC.Parser.DecomposeQI ("System.Boolean[]", start);
+                               AddVariable (e, Block.lateBindingCopyBack, null, start);
+                       }
                        
                        this.Parent = parent;
                        this.Implicit = implicit_block;
+                       this.parameters = parameters;
                        this.StartLocation = start;
                        this.EndLocation = end;
                        this.loc = start;
@@ -903,12 +2888,21 @@ namespace Mono.CSharp {
                        statements = new ArrayList ();
                }
 
+               public bool IsLateBindingRequired {
+                       get {
+                               return isLateBindingRequired;
+                       }
+                       set {
+                               isLateBindingRequired = value;
+                       }
+               }
+
                public int ID {
                        get {
                                return this_id;
                        }
                }
-               
+
                void AddChild (Block b)
                {
                        if (children == null)
@@ -934,7 +2928,7 @@ namespace Mono.CSharp {
                public bool AddLabel (string name, LabeledStatement target)
                {
                        if (labels == null)
-                               labels = new Hashtable ();
+                               labels = new CaseInsensitiveHashtable ();
                        if (labels.Contains (name))
                                return false;
                        
@@ -955,36 +2949,149 @@ namespace Mono.CSharp {
                        return null;
                }
 
-               public VariableInfo AddVariable (string type, string name, Parameters pars, Location l)
+               VariableInfo this_variable = null;
+
+               // <summary>
+               //   Returns the "this" instance variable of this block.
+               //   See AddThisVariable() for more information.
+               // </summary>
+               public VariableInfo ThisVariable {
+                       get {
+                               if (this_variable != null)
+                                       return this_variable;
+                               else if (Parent != null)
+                                       return Parent.ThisVariable;
+                               else
+                                       return null;
+                       }
+               }
+
+               Hashtable child_variable_names;
+
+               // <summary>
+               //   Marks a variable with name @name as being used in a child block.
+               //   If a variable name has been used in a child block, it's illegal to
+               //   declare a variable with the same name in the current block.
+               // </summary>
+               public void AddChildVariableName (string name)
+               {
+                       if (child_variable_names == null)
+                               child_variable_names = new CaseInsensitiveHashtable ();
+
+                       if (!child_variable_names.Contains (name))
+                               child_variable_names.Add (name, true);
+               }
+
+               // <summary>
+               //   Marks all variables from block @block and all its children as being
+               //   used in a child block.
+               // </summary>
+               public void AddChildVariableNames (Block block)
+               {
+                       if (block.Variables != null) {
+                               foreach (string name in block.Variables.Keys)
+                                       AddChildVariableName (name);
+                       }
+
+                       foreach (Block child in block.children) {
+                               if (child.Variables != null) {
+                                       foreach (string name in child.Variables.Keys)
+                                               AddChildVariableName (name);
+                               }
+                       }
+               }
+
+               // <summary>
+               //   Checks whether a variable name has already been used in a child block.
+               // </summary>
+               public bool IsVariableNameUsedInChildBlock (string name)
+               {
+                       if (child_variable_names == null)
+                               return false;
+
+                       return child_variable_names.Contains (name);
+               }
+
+               // <summary>
+               //   This is used by non-static `struct' constructors which do not have an
+               //   initializer - in this case, the constructor must initialize all of the
+               //   struct's fields.  To do this, we add a "this" variable and use the flow
+               //   analysis code to ensure that it's been fully initialized before control
+               //   leaves the constructor.
+               // </summary>
+               public VariableInfo AddThisVariable (TypeContainer tc, Location l)
+               {
+                       if (this_variable != null)
+                               return this_variable;
+
+                       this_variable = new VariableInfo (tc, ID, l);
+
+                       if (variables == null)
+                               variables = new CaseInsensitiveHashtable ();
+                       variables.Add ("this", this_variable);
+
+                       return this_variable;
+               }
+
+               public VariableInfo AddVariable (Expression type, string name, Parameters pars, Location l)
                {
                        if (variables == null)
-                               variables = new Hashtable ();
+                               variables = new CaseInsensitiveHashtable ();
+
+                       VariableInfo vi = GetVariableInfo (name);
+                       if (vi != null) {
+                               if (vi.Block != ID)
+                                       Report.Error (30616, l, "A local variable named `" + name + "' " +
+                                                     "cannot be declared in this scope since it would " +
+                                                     "give a different meaning to `" + name + "', which " +
+                                                     "is already used in a `parent or current' scope to " +
+                                                     "denote something else");
+                               else
+                                       Report.Error (30290, l, "A local variable `" + name + "' is already " +
+                                                     "defined in this scope");
+                               return null;
+                       }
 
-                       if (GetVariableType (name) != null)
+                       if (IsVariableNameUsedInChildBlock (name)) {
+                               Report.Error (136, l, "A local variable named `" + name + "' " +
+                                             "cannot be declared in this scope since it would " +
+                                             "give a different meaning to `" + name + "', which " +
+                                             "is already used in a `child' scope to denote something " +
+                                             "else");
                                return null;
+                       }
 
                        if (pars != null) {
                                int idx = 0;
                                Parameter p = pars.GetParameterByName (name, out idx);
-                               if (p != null) 
+                               if (p != null) {
+                                       Report.Error (30616, l, "A local variable named `" + name + "' " +
+                                                     "cannot be declared in this scope since it would " +
+                                                     "give a different meaning to `" + name + "', which " +
+                                                     "is already used in a `parent or current' scope to " +
+                                                     "denote something else");
                                        return null;
+                               }
                        }
                        
-                       VariableInfo vi = new VariableInfo (type, l);
+                       vi = new VariableInfo (type, name, ID, l);
 
                        variables.Add (name, vi);
 
+                       if (variables_initialized)
+                               throw new Exception ();
+
                        // Console.WriteLine ("Adding {0} to {1}", name, ID);
                        return vi;
                }
 
-               public bool AddConstant (string type, string name, Expression value, Parameters pars, Location l)
+               public bool AddConstant (Expression type, string name, Expression value, Parameters pars, Location l)
                {
                        if (AddVariable (type, name, pars, l) == null)
                                return false;
                        
                        if (constants == null)
-                               constants = new Hashtable ();
+                               constants = new CaseInsensitiveHashtable ();
 
                        constants.Add (name, value);
                        return true;
@@ -1013,7 +3120,7 @@ namespace Mono.CSharp {
                        return null;
                }
                
-               public string GetVariableType (string name)
+               public Expression GetVariableType (string name)
                {
                        VariableInfo vi = GetVariableInfo (name);
 
@@ -1078,6 +3185,16 @@ namespace Mono.CSharp {
                        }
                }
 
+               Parameters parameters = null;
+               public Parameters Parameters {
+                       get {
+                               if (Parent != null)
+                                       return Parent.Parameters;
+
+                               return parameters;
+                       }
+               }
+
                /// <returns>
                ///   A list of labels that were not used within this block
                /// </returns>
@@ -1087,23 +3204,67 @@ namespace Mono.CSharp {
                        return null;
                }
 
-               public void AddStatement (Statement s)
-               {
-                       statements.Add (s);
-                       used = true;
+               public void AddStatement (Statement s)
+               {
+                       statements.Add (s);
+                       used = true;
+               }
+
+               public bool Used {
+                       get {
+                               return used;
+                       }
+               }
+
+               public void Use ()
+               {
+                       used = true;
+               }
+
+               bool variables_initialized = false;
+               int count_variables = 0, first_variable = 0;
+
+               void UpdateVariableInfo (EmitContext ec)
+               {
+                       DeclSpace ds = ec.DeclSpace;
+
+                       first_variable = 0;
+
+                       if (Parent != null)
+                               first_variable += Parent.CountVariables;
+
+                       count_variables = first_variable;
+                       if (variables != null) {
+                               foreach (VariableInfo vi in variables.Values) {
+                                       if (!vi.Resolve (ds)) {
+                                               vi.Number = -1;
+                                               continue;
+                                       }
+
+                                       vi.Number = ++count_variables;
+
+                                       if (vi.StructInfo != null)
+                                               count_variables += vi.StructInfo.Count;
+                               }
+                       }
+
+                       variables_initialized = true;
                }
 
-               public bool Used {
+               //
+               // <returns>
+               //   The number of local variables in this block
+               // </returns>
+               public int CountVariables
+               {
                        get {
-                               return used;
+                               if (!variables_initialized)
+                                       throw new Exception ();
+
+                               return count_variables;
                        }
                }
 
-               public void Use ()
-               {
-                       used = true;
-               }
-               
                /// <summary>
                ///   Emits the variable declarations and labels.
                /// </summary>
@@ -1115,26 +3276,34 @@ namespace Mono.CSharp {
                /// </remarks>
                public void EmitMeta (EmitContext ec, Block toplevel)
                {
-                       DeclSpace ds = ec.DeclSpace;
+                       //DeclSpace ds = ec.DeclSpace;
                        ILGenerator ig = ec.ig;
-                               
+
+                       if (!variables_initialized)
+                               UpdateVariableInfo (ec);
+
                        //
                        // Process this block variables
                        //
                        if (variables != null){
-                               local_builders = new Hashtable ();
+                               //local_builders = new CaseInsensitiveHashtable ();
                                
                                foreach (DictionaryEntry de in variables){
                                        string name = (string) de.Key;
+                                       /*
+                                       if (!isLateBindingRequired) {
+                                               if (name.Equals (Block.lateBindingArgs) || 
+                                                   name.Equals (Block.lateBindingArgNames) ||
+                                                   name.Equals (Block.lateBindingCopyBack))
+                                                       continue;
+                                       }
+                                       */
                                        VariableInfo vi = (VariableInfo) de.Value;
-                                       Type t;
 
-                                       t = RootContext.LookupType (ds, vi.Type, false, vi.Location);
-                                       if (t == null)
+                                       if (vi.VariableType == null)
                                                continue;
 
-                                       vi.VariableType = t;
-                                       vi.LocalBuilder = ig.DeclareLocal (t);
+                                       vi.LocalBuilder = ig.DeclareLocal (vi.VariableType);
 
                                        if (CodeGen.SymbolWriter != null)
                                                vi.LocalBuilder.SetLocalSymInfo (name);
@@ -1202,63 +3371,391 @@ namespace Mono.CSharp {
                                        b.UsageWarning ();
                }
 
+               bool has_ret = false;
+
                public override bool Resolve (EmitContext ec)
                {
                        Block prev_block = ec.CurrentBlock;
+                       bool ok = true;
 
                        ec.CurrentBlock = this;
-                       foreach (Statement s in statements){
-                               if (s.Resolve (ec) == false){
-                                       ec.CurrentBlock = prev_block;
-                                       return false;
+
+                       if (!variables_initialized)
+                               UpdateVariableInfo (ec);
+
+                       ec.StartFlowBranching (this);
+
+                       Report.Debug (1, "RESOLVE BLOCK", StartLocation, ec.CurrentBranching);
+
+                       ArrayList new_statements = new ArrayList ();
+                       bool unreachable = false, warning_shown = false;
+
+                       foreach (Statement s in statements){
+                               if (unreachable && !(s is LabeledStatement)) {
+                                       if (!warning_shown && !(s is EmptyStatement)) {
+                                               warning_shown = true;
+                                               Warning_DeadCodeFound (s.loc);
+                                       }
+                                       continue;
+                               }
+
+                               if (s.Resolve (ec) == false) {
+                                       ok = false;
+                                       continue;
                                }
+
+                               if (s is LabeledStatement)
+                                       unreachable = false;
+                               else
+                                       unreachable = ! ec.CurrentBranching.IsReachable ();
+
+                               new_statements.Add (s);
                        }
 
+                       statements = new_statements;
+
+                       Report.Debug (1, "RESOLVE BLOCK DONE", StartLocation, ec.CurrentBranching);
+
+                       FlowReturns returns = ec.EndFlowBranching ();
                        ec.CurrentBlock = prev_block;
-                       return true;
+
+                       // If we're a non-static `struct' constructor which doesn't have an
+                       // initializer, then we must initialize all of the struct's fields.
+                       if ((this_variable != null) && (returns != FlowReturns.EXCEPTION) &&
+                           !this_variable.IsAssigned (ec, loc))
+                               ok = false;
+
+                       if ((labels != null) && (RootContext.WarningLevel >= 2)) {
+                               foreach (LabeledStatement label in labels.Values)
+                                       if (!label.HasBeenReferenced)
+                                               Report.Warning (164, label.Location,
+                                                               "This label has not been referenced");
+                       }
+
+                       if ((returns == FlowReturns.ALWAYS) ||
+                           (returns == FlowReturns.EXCEPTION) ||
+                           (returns == FlowReturns.UNREACHABLE))
+                               has_ret = true;
+
+                       return ok;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
-                       bool is_ret = false;
                        Block prev_block = ec.CurrentBlock;
-                       
+
                        ec.CurrentBlock = this;
 
-                       if (CodeGen.SymbolWriter != null) {
-                               ec.Mark (StartLocation);
+                       ec.Mark (StartLocation);
+                       foreach (Statement s in statements)
+                               s.Emit (ec);
                                
-                               foreach (Statement s in statements) {
-                                       ec.Mark (s.loc);
-                                       
-                                       is_ret = s.Emit (ec);
+                       ec.Mark (EndLocation); 
+                       
+                       ec.CurrentBlock = prev_block;
+                       return has_ret;
+               }
+       }
+
+       public class StatementSequence : Expression {
+               Block stmtBlock;
+               ArrayList args, originalArgs;
+               Expression expr;
+               bool isRetValRequired;
+               bool isLeftHandSide;
+               bool isIndexerAccess;
+               string memberName;
+               Expression type_expr;
+
+               public StatementSequence (Block parent, Location loc, Expression expr) 
+                       : this (parent, loc, expr, null)
+               { }
+
+               public StatementSequence (Block parent, Location loc, Expression expr, string name, 
+                                         Expression type_expr, ArrayList a, bool isRetValRequired,
+                                         bool isLeftHandSide) 
+                       : this (parent, loc, expr, a)
+               {
+                       this.memberName = name;
+                       this.type_expr = type_expr;
+                       this.isRetValRequired = isRetValRequired;
+                       this.isLeftHandSide = isLeftHandSide;
+               }
+
+               public StatementSequence (Block parent, Location loc, Expression expr, ArrayList a,
+                                         bool isRetValRequired, bool isLeftHandSide) 
+                       : this (parent, loc, expr, a)
+               {
+                       this.isRetValRequired = isRetValRequired;
+                       this.isLeftHandSide = isLeftHandSide;
+                       if (expr is MemberAccess) {
+                               this.expr = ((MemberAccess)expr).Expr;
+                               this.memberName = ((MemberAccess)expr).Identifier;
+                               this.isIndexerAccess = false;
+                       } else if (expr is IndexerAccess) {
+                               this.expr = ((IndexerAccess) expr).Instance;
+                               this.memberName = "";
+                               this.isIndexerAccess = true;
+                       }
+               }
+
+               public StatementSequence (Block parent, Location loc, Expression expr, ArrayList a) 
+               {
+                       stmtBlock = new Block (parent);
+                       args = a;
+                       originalArgs = new ArrayList ();
+                       if (args != null) {
+                               for (int index = 0; index < a.Count; index ++) {
+                                       Argument argument = (Argument) args [index];
+                                       originalArgs.Add (new Argument (argument.Expr, argument.ArgType));
                                }
+                       }
 
-                               ec.Mark (EndLocation); 
-                       } else {
-                               foreach (Statement s in statements)
-                                       is_ret = s.Emit (ec);
+                       this.expr = expr;
+                       stmtBlock.IsLateBindingRequired = true;
+                       this.loc = loc;
+                       this.isRetValRequired = this.isLeftHandSide = false;
+                       this.memberName = "";
+                       this.type_expr = null;
+               }
+
+               public ArrayList Arguments {
+                       get {
+                               return args;
+                       }
+                       set {
+                               args = value;
+                       }
+               }
+
+               public bool IsLeftHandSide {
+                       set {
+                               isLeftHandSide = value;
+                       }
+               }
+
+               public Block StmtBlock {
+                       get {
+                               return stmtBlock;
+                       }
+               }
+               
+               public override Expression DoResolve (EmitContext ec)
+               {
+                       if (!stmtBlock.Resolve (ec))
+                               return null;
+                       eclass = ExprClass.Value;
+                       type = TypeManager.object_type;
+                       return this;
+               }
+
+               public bool ResolveArguments (EmitContext ec) {
+               
+                       bool argNamesFound = false;
+                       if (Arguments != null)
+                       {
+                               for (int index = 0; index < Arguments.Count; index ++)
+                               {
+                                       Argument a = (Argument) Arguments [index];
+                                       if (a.ParamName == null || a.ParamName == "") {
+                                               if (argNamesFound) {
+                                                       Report.Error (30241, loc, "Named Argument expected");
+                                                       return false;
+                                               }
+                                       } else
+                                               argNamesFound = true;
+                                       if (a.ArgType == Argument.AType.NoArg)
+                                               a = new Argument (Parser.DecomposeQI ("System.Reflection.Missing.Value", loc), Argument.AType.Expression);
+                                       if (!a.Resolve (ec, loc))
+                                               return false;                           
+                                       Arguments [index] = a;
+                               }
                        }
+                       return true;
+               }
                        
-                       ec.CurrentBlock = prev_block;
-                       return is_ret;
+               public void GenerateLateBindingStatements ()
+               {
+                       int argCount = 0;
+                       ArrayList arrayInitializers = new ArrayList ();
+                       ArrayList ArgumentNames = null;
+                       if (args != null) {
+                               //arrayInitializers = new ArrayList ();
+                               argCount = args.Count;
+                               for (int index = 0; index < args.Count; index ++) {
+                                       Argument a = (Argument) args [index];
+                                       Expression argument = a.Expr;
+                                       arrayInitializers.Add (argument);
+                                       if (a.ParamName != null && a.ParamName != "") {
+                                               if (ArgumentNames == null)
+                                                       ArgumentNames = new ArrayList ();
+                                               ArgumentNames.Add (new StringLiteral (a.ParamName));
+                                       }
+                               }
+                       }
+
+                       // __LateBindingArgs = new Object () {arg1, arg2 ...}
+                       ArrayCreation new_expr = new ArrayCreation (Parser.DecomposeQI ("System.Object",  loc), "[]", arrayInitializers, loc);
+                       Assign assign_stmt = null;
+
+                       LocalVariableReference v1 = new LocalVariableReference (stmtBlock, Block.lateBindingArgs, loc);
+                       assign_stmt = new Assign (v1, new_expr, loc);
+                       stmtBlock.AddStatement (new StatementExpression ((ExpressionStatement) assign_stmt, loc));
+                       // __LateBindingArgNames = new string () { argument names}
+                       LocalVariableReference v2 = null;
+                       if (ArgumentNames != null && ArgumentNames.Count > 0) {
+                               new_expr = new ArrayCreation (Parser.DecomposeQI ("System.String",  loc), "[]", ArgumentNames, loc);
+                               v2 = new LocalVariableReference (stmtBlock, Block.lateBindingArgNames, loc);
+                               assign_stmt = new Assign (v2, new_expr, loc);
+                               stmtBlock.AddStatement (new StatementExpression ((ExpressionStatement) assign_stmt, loc));
+                       }
+
+                       //string memName = "";
+                       //bool isIndexerAccess = true;
+
+                       ArrayList invocationArgs = new ArrayList ();
+                       if (isIndexerAccess || memberName == "") {
+                               invocationArgs.Add (new Argument (expr, Argument.AType.Expression));
+                               invocationArgs.Add (new Argument (v1, Argument.AType.Expression));
+                               invocationArgs.Add (new Argument (NullLiteral.Null, Argument.AType.Expression));
+                               Expression tmp = null;
+                               if (!isLeftHandSide)
+                                       tmp = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.LateBinding.LateIndexGet", loc);
+                               else
+                                       tmp = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.LateBinding.LateIndexSet", loc);
+                               Invocation invStmt = new Invocation (tmp, invocationArgs, Location.Null);
+                               invStmt.IsLateBinding = true;
+                               stmtBlock.AddStatement (new StatementExpression ((ExpressionStatement) invStmt, loc));
+                               return;
+                       }
+
+                       if (expr != null)
+                               invocationArgs.Add (new Argument (expr, Argument.AType.Expression));
+                       else
+                               invocationArgs.Add (new Argument (NullLiteral.Null, Argument.AType.Expression));
+                       if (type_expr != null)
+                               invocationArgs.Add (new Argument (type_expr, Argument.AType.Expression));
+                       else
+                               invocationArgs.Add (new Argument (NullLiteral.Null, Argument.AType.Expression));
+                       invocationArgs.Add (new Argument (new StringLiteral (memberName), Argument.AType.Expression));
+                       invocationArgs.Add (new Argument (v1, Argument.AType.Expression));
+                       if (ArgumentNames != null && ArgumentNames.Count > 0)
+                               invocationArgs.Add (new Argument (v2, Argument.AType.Expression));
+                       else
+                               invocationArgs.Add (new Argument (NullLiteral.Null, Argument.AType.Expression));
+
+                       // __LateBindingCopyBack = new Boolean (no_of_args) {}
+                       bool isCopyBackRequired = false;
+                       if (!isLeftHandSide) {
+                               for (int i = 0; i < argCount; i++) {
+                                       Argument origArg = (Argument) Arguments [i];
+                                       Expression origExpr = origArg.Expr; 
+                                       if (!(origExpr is Constant || origArg.ArgType == Argument.AType.NoArg)) 
+                                               isCopyBackRequired = true;
+                               }
+                       }
+
+                       LocalVariableReference v3 = new LocalVariableReference (stmtBlock, Block.lateBindingCopyBack, loc);
+                       if (isCopyBackRequired) {
+                               ArrayList rank_specifier = new ArrayList ();
+                               rank_specifier.Add (new IntLiteral (argCount));
+                               arrayInitializers = new ArrayList ();
+                               for (int i = 0; i < argCount; i++) {
+                                       Argument a = (Argument) Arguments [i];
+                                       Expression origExpr = a.Expr;
+                                       if (origExpr is Constant || a.ArgType == Argument.AType.NoArg || origExpr is New)
+                                               arrayInitializers.Add (new BoolLiteral (false));
+                                       else 
+                                               arrayInitializers.Add (new BoolLiteral (true));
+                               }
+       
+                               new_expr = new ArrayCreation (Parser.DecomposeQI ("System.Boolean",  loc), "[]", arrayInitializers, loc);
+                               assign_stmt = new Assign (v3, new_expr, loc);
+                               stmtBlock.AddStatement (new StatementExpression ((ExpressionStatement) assign_stmt, loc));
+                               invocationArgs.Add (new Argument (v3, Argument.AType.Expression));
+                       } else if (! isLeftHandSide) {
+                               invocationArgs.Add (new Argument (NullLiteral.Null, Argument.AType.Expression));
+                       }
+
+                       Expression etmp = null;
+                       if (isLeftHandSide) {
+                               // LateSet
+                               etmp = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.LateBinding.LateSet", loc);
+                       } else if (isRetValRequired) {
+                               // Late Get
+                               etmp = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.LateBinding.LateGet", loc);
+                       }  else {
+                               etmp = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.LateBinding.LateCall", loc);
+                       }
+
+                       Invocation inv_stmt = new Invocation (etmp, invocationArgs, Location.Null);
+                       inv_stmt.IsLateBinding = true;
+                       stmtBlock.AddStatement (new StatementExpression ((ExpressionStatement) inv_stmt, loc));
+
+                       if (! isCopyBackRequired)
+                               return;
+
+                       for (int i = argCount - 1; i >= 0; i --) {
+                               Argument arg = (Argument) originalArgs [i];
+                               Expression origExpr = (Expression) arg.Expr;
+                               if (arg.ArgType == Argument.AType.NoArg)
+                                       continue;
+                               if (origExpr is Constant)
+                                       continue;
+                               if (origExpr is New)
+                                       continue;
+
+                               Expression intExpr = new IntLiteral (i);
+                               ArrayList argsLocal = new ArrayList ();
+                               argsLocal.Add (new Argument (intExpr, Argument.AType.Expression));
+                               Expression indexExpr = new Invocation (new SimpleName (Block.lateBindingCopyBack, loc), argsLocal, loc);
+                               Expression value = new Invocation (new SimpleName (Block.lateBindingArgs, loc), argsLocal, loc);
+                               assign_stmt = new Assign (origExpr, value,  loc);
+                               Expression boolExpr = new Binary (Binary.Operator.Inequality, indexExpr, new BoolLiteral (false), loc);
+                               Statement ifStmt = new If (boolExpr, new StatementExpression ((ExpressionStatement) assign_stmt, loc), loc);
+                               stmtBlock.AddStatement (ifStmt);
+                       }
+               }
+
+               public override void Emit (EmitContext ec)
+               {
+                       stmtBlock.Emit (ec);
                }
        }
 
        public class SwitchLabel {
-               Expression label;
-               object converted;
+               public enum LabelType : byte {
+                       Operator, Range, Label, Else
+               }
+
+               Expression label, start, end;
+               LabelType label_type;
+               Expression label_condition, start_condition, end_condition;
+               Binary.Operator oper;
                public Location loc;
                public Label ILLabel;
                public Label ILLabelCode;
-               
+
                //
                // if expr == null, then it is the default case.
                //
-               public SwitchLabel (Expression expr, Location l)
+               public SwitchLabel (Expression start, Expression end, LabelType ltype, Binary.Operator oper, Location l) {
+                       this.start = start;
+                       this.end = end;
+                       this.label_type = ltype;
+                       this.oper = oper;
+                       this.loc = l;
+                       label_condition = start_condition = end_condition = null;
+               }
+
+               public SwitchLabel (Expression expr, LabelType ltype, Binary.Operator oper, Location l)
                {
                        label = expr;
+                       start = end = null;
+                       label_condition = start_condition = end_condition = null;
                        loc = l;
+                       this.label_type = ltype;
+                       this.oper = oper;
                }
 
                public Expression Label {
@@ -1267,47 +3764,83 @@ namespace Mono.CSharp {
                        }
                }
 
-               public object Converted {
+               public LabelType Type {
                        get {
-                               return converted;
+                               return label_type;
                        }
                }
-               
+
+               public Expression ConditionStart {
+                       get {
+                               return start_condition;
+                       }
+               }
+
+               public Expression ConditionEnd {
+                       get {
+                               return end_condition;
+                       }
+               }
+
+               public Expression ConditionLabel {
+                       get {
+                               return label_condition;
+                       }
+               }
+
                //
                // Resolves the expression, reduces it to a literal if possible
                // and then converts it to the requested type.
                //
-               public bool ResolveAndReduce (EmitContext ec, Type required_type)
+               public bool ResolveAndReduce (EmitContext ec, Expression expr)
                {
                        ILLabel = ec.ig.DefineLabel ();
                        ILLabelCode = ec.ig.DefineLabel ();
 
-                       if (label == null)
+                       Expression e = null;
+                       switch (label_type) {
+                       case LabelType.Label :
+                               if (label == null)
+                                       return false;
+                               e = label.Resolve (ec);
+                               if (e != null)
+                                       e = Expression.ConvertImplicit (ec, e, expr.Type, loc);
+                               if (e == null)
+                                       return false;
+                               label_condition = new Binary (Binary.Operator.Equality, expr, e, loc);
+                               if ((label_condition = label_condition.DoResolve (ec)) == null)
+                                       return false;
+                               return true;
+                       case LabelType.Operator :
+                               e = label.Resolve (ec);
+                               label_condition = new Binary (oper, expr, e, loc);
+                               if ((label_condition = label_condition.DoResolve (ec)) == null)
+                                       return false;
+                               return true;
+                       case LabelType.Range :
+                               if (start == null || end == null)
+                                       return false;
+                               e = start.Resolve (ec);
+                               if (e != null)
+                                       e = Expression.ConvertImplicit (ec, e, expr.Type, loc);
+                               if (e == null)
+                                       return false;
+                               start_condition = new Binary (Binary.Operator.GreaterThanOrEqual, expr, e, loc);
+                               start_condition = start_condition.Resolve (ec);
+                               e = end.Resolve (ec);
+                               if (e != null)
+                                       e = Expression.ConvertImplicit (ec, e, expr.Type, loc);
+                               if (e == null)
+                                       return false;
+                               end_condition = new Binary (Binary.Operator.LessThanOrEqual, expr, e, loc);
+                               end_condition = end_condition.Resolve (ec);
+                               if (start_condition == null || end_condition == null)
+                                       return false;
                                return true;
-                       
-                       Expression e = label.Resolve (ec);
-
-                       if (e == null)
-                               return false;
-
-                       if (!(e is Constant)){
-                               Console.WriteLine ("Value is: " + label);
-                               Report.Error (150, loc, "A constant value is expected");
-                               return false;
-                       }
 
-                       if (e is StringConstant || e is NullLiteral){
-                               if (required_type == TypeManager.string_type){
-                                       converted = label;
-                                       ILLabel = ec.ig.DefineLabel ();
-                                       return true;
-                               }
+                       case LabelType.Else :
+                               break;
                        }
-
-                       converted = Expression.ConvertIntLiteral ((Constant) e, required_type, loc);
-                       if (converted == null)
-                               return false;
-
                        return true;
                }
        }
@@ -1343,12 +3876,13 @@ namespace Mono.CSharp {
                //
                bool got_default;
                Label default_target;
-               
+               Expression new_expr;
+
                //
                // The types allowed to be implicitly cast from
                // on the governing type
                //
-               static Type [] allowed_types;
+               //static Type [] allowed_types;
                
                public Switch (Expression e, ArrayList sects, Location l)
                {
@@ -1377,20 +3911,21 @@ namespace Mono.CSharp {
                //
                Expression SwitchGoverningType (EmitContext ec, Type t)
                {
-                       if (t == TypeManager.int32_type ||
-                           t == TypeManager.uint32_type ||
-                           t == TypeManager.char_type ||
-                           t == TypeManager.byte_type ||
-                           t == TypeManager.sbyte_type ||
-                           t == TypeManager.ushort_type ||
+                       if (t == TypeManager.byte_type ||
                            t == TypeManager.short_type ||
-                           t == TypeManager.uint64_type ||
+                           t == TypeManager.int32_type ||
                            t == TypeManager.int64_type ||
+                           t == TypeManager.decimal_type ||
+                           t == TypeManager.float_type ||
+                           t == TypeManager.double_type ||
+                           t == TypeManager.date_type ||
+                           t == TypeManager.char_type ||
+                           t == TypeManager.object_type ||
                            t == TypeManager.string_type ||
                                t == TypeManager.bool_type ||
                                t.IsSubclassOf (TypeManager.enum_type))
                                return Expr;
-
+/*
                        if (allowed_types == null){
                                allowed_types = new Type [] {
                                        TypeManager.sbyte_type,
@@ -1424,12 +3959,14 @@ namespace Mono.CSharp {
                                if (converted != null){
                                        Report.Error (-12, loc, "More than one conversion to an integral " +
                                                      " type exists for type `" +
-                                                     TypeManager.CSharpName (Expr.Type)+"'");
+                                                     TypeManager.MonoBASIC_Name (Expr.Type)+"'");
                                        return null;
                                } else
                                        converted = e;
                        }
                        return converted;
+*/
+                       return null;
                }
 
                void error152 (string n)
@@ -1448,25 +3985,29 @@ namespace Mono.CSharp {
                //
                bool CheckSwitch (EmitContext ec)
                {
-                       Type compare_type;
+                       //Type compare_type;
                        bool error = false;
-                       Elements = new Hashtable ();
+                       Elements = new CaseInsensitiveHashtable ();
                                
                        got_default = false;
 
+/*
                        if (TypeManager.IsEnumType (SwitchType)){
                                compare_type = TypeManager.EnumToUnderlying (SwitchType);
                        } else
                                compare_type = SwitchType;
+*/
                        
-                       foreach (SwitchSection ss in Sections){
-                               foreach (SwitchLabel sl in ss.Labels){
-                                       if (!sl.ResolveAndReduce (ec, SwitchType)){
+                       for (int secIndex = 0; secIndex < Sections.Count; secIndex ++) {
+                               SwitchSection ss = (SwitchSection) Sections [secIndex];
+                               for (int labelIndex = 0; labelIndex < ss.Labels.Count; labelIndex ++) {
+                                       SwitchLabel sl  = (SwitchLabel) ss.Labels [labelIndex];
+                                       if (!sl.ResolveAndReduce (ec, Expr)){
                                                error = true;
                                                continue;
                                        }
 
-                                       if (sl.Label == null){
+                                       if (sl.Type == SwitchLabel.LabelType.Else){
                                                if (got_default){
                                                        error152 ("default");
                                                        error = true;
@@ -1474,111 +4015,6 @@ namespace Mono.CSharp {
                                                got_default = true;
                                                continue;
                                        }
-                                       
-                                       object key = sl.Converted;
-
-                                       if (key is Constant)
-                                               key = ((Constant) key).GetValue ();
-
-                                       if (key == null)
-                                               key = NullLiteral.Null;
-                                       
-                                       string lname = null;
-                                       if (compare_type == TypeManager.uint64_type){
-                                               ulong v = (ulong) key;
-
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.int64_type){
-                                               long v = (long) key;
-
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.uint32_type){
-                                               uint v = (uint) key;
-
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.char_type){
-                                               char v = (char) key;
-                                               
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.byte_type){
-                                               byte v = (byte) key;
-                                               
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.sbyte_type){
-                                               sbyte v = (sbyte) key;
-                                               
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.short_type){
-                                               short v = (short) key;
-                                               
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.ushort_type){
-                                               ushort v = (ushort) key;
-                                               
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.string_type){
-                                               if (key is NullLiteral){
-                                                       if (Elements.Contains (NullLiteral.Null))
-                                                               lname = "null";
-                                                       else
-                                                               Elements.Add (NullLiteral.Null, null);
-                                               } else {
-                                                       string s = (string) key;
-
-                                                       if (Elements.Contains (s))
-                                                               lname = s;
-                                                       else
-                                                               Elements.Add (s, sl);
-                                               }
-                                       } else if (compare_type == TypeManager.int32_type) {
-                                               int v = (int) key;
-
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       } else if (compare_type == TypeManager.bool_type) {
-                                               bool v = (bool) key;
-
-                                               if (Elements.Contains (v))
-                                                       lname = v.ToString ();
-                                               else
-                                                       Elements.Add (v, sl);
-                                       }
-                                       else
-                                       {
-                                               throw new Exception ("Unknown switch type!" +
-                                                                    SwitchType + " " + compare_type);
-                                       }
-
-                                       if (lname != null){
-                                               error152 ("case + " + lname);
-                                               error = true;
-                                       }
                                }
                        }
                        if (error)
@@ -1663,6 +4099,7 @@ namespace Mono.CSharp {
                        }
                }
 
+/*
                /// <summary>
                /// This method emits code for a lookup-based switch statement (non-string)
                /// Basically it groups the cases into blocks that are at least half full,
@@ -1846,12 +4283,15 @@ namespace Mono.CSharp {
                                                fFoundDefault = true;
                                        }
                                }
-                               fAllReturn &= ss.Block.Emit (ec);
+                               bool returns = ss.Block.Emit (ec);
+                               fAllReturn &= returns;
                                //ig.Emit (OpCodes.Br, lblEnd);
                        }
                        
-                       if (!fFoundDefault)
+                       if (!fFoundDefault) {
                                ig.MarkLabel (lblDefault);
+                               fAllReturn = false;
+                       }
                        ig.MarkLabel (lblEnd);
 
                        return fAllReturn;
@@ -1892,9 +4332,6 @@ namespace Mono.CSharp {
                                ig.Emit (OpCodes.Call, TypeManager.string_isinterneted_string);
                                ig.Emit (OpCodes.Stloc, val);
                        }
-
-                       SwitchSection last_section;
-                       last_section = (SwitchSection) Sections [Sections.Count-1];
                        
                        foreach (SwitchSection ss in Sections){
                                Label sec_begin = ig.DefineLabel ();
@@ -1947,7 +4384,7 @@ namespace Mono.CSharp {
                                                }
                                        }
                                }
-                               if (label_count != 1 && ss != last_section)
+                               if (label_count != 1)
                                        ig.Emit (OpCodes.Br, next_test);
                                
                                if (null_found)
@@ -1955,7 +4392,9 @@ namespace Mono.CSharp {
                                ig.MarkLabel (sec_begin);
                                foreach (SwitchLabel sl in ss.Labels)
                                        ig.MarkLabel (sl.ILLabelCode);
-                               if (ss.Block.Emit (ec))
+
+                               bool returns = ss.Block.Emit (ec);
+                               if (returns)
                                        pending_goto_end = false;
                                else {
                                        all_return = false;
@@ -1972,26 +4411,17 @@ namespace Mono.CSharp {
                        
                        return all_return;
                }
+*/
 
                public override bool Resolve (EmitContext ec)
-               {
-                       foreach (SwitchSection ss in Sections){
-                               if (ss.Block.Resolve (ec) != true)
-                                       return false;
-                       }
-
-                       return true;
-               }
-               
-               public override bool Emit (EmitContext ec)
                {
                        Expr = Expr.Resolve (ec);
                        if (Expr == null)
                                return false;
 
-                       Expression new_expr = SwitchGoverningType (ec, Expr.Type);
+                       new_expr = SwitchGoverningType (ec, Expr.Type);
                        if (new_expr == null){
-                               Report.Error (151, loc, "An integer type or string was expected for switch");
+                               Report.Error (30338, loc, "'Select' expression cannot be of type '" + Expr.Type +"'");
                                return false;
                        }
 
@@ -2001,15 +4431,36 @@ namespace Mono.CSharp {
                        if (!CheckSwitch (ec))
                                return false;
 
-                       // Store variable for comparission purposes
-                       LocalBuilder value = ec.ig.DeclareLocal (SwitchType);
-                       new_expr.Emit (ec);
-                       ec.ig.Emit (OpCodes.Stloc, value);
+                       Switch old_switch = ec.Switch;
+                       ec.Switch = this;
+                       ec.Switch.SwitchType = SwitchType;
+
+                       ec.StartFlowBranching (FlowBranchingType.SWITCH, loc);
 
-                       ILGenerator ig = ec.ig;
+                       bool first = true;
+                       foreach (SwitchSection ss in Sections){
+                               if (!first)
+                                       ec.CurrentBranching.CreateSibling ();
+                               else
+                                       first = false;
+
+                               if (ss.Block.Resolve (ec) != true)
+                                       return false;
+                       }
 
-                       default_target = ig.DefineLabel ();
 
+                       if (!got_default)
+                               ec.CurrentBranching.CreateSibling ();
+
+                       ec.EndFlowBranching ();
+                       ec.Switch = old_switch;
+
+                       return true;
+               }
+               
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       ILGenerator ig = ec.ig;
                        //
                        // Setup the codegen context
                        //
@@ -2019,12 +4470,47 @@ namespace Mono.CSharp {
                        ec.LoopEnd = ig.DefineLabel ();
                        ec.Switch = this;
 
-                       // Emit Code.
-                       bool all_return;
-                       if (SwitchType == TypeManager.string_type)
-                               all_return = SimpleSwitchEmit (ec, value);
-                       else
-                               all_return = TableSwitchEmit (ec, value);
+                       for (int secIndex = 0; secIndex < Sections.Count; secIndex ++) {
+                               SwitchSection section = (SwitchSection) Sections [secIndex];
+                               Label sLabel = ig.DefineLabel ();
+                               Label lLabel = ig.DefineLabel ();
+                               ArrayList Labels = section.Labels;
+                               for (int labelIndex = 0; labelIndex < Labels.Count; labelIndex ++) {
+                                       SwitchLabel sl = (SwitchLabel) Labels [labelIndex];
+                                       switch (sl.Type) {
+                                       case SwitchLabel.LabelType.Range :
+                                               if (labelIndex + 1 == Labels.Count) {
+                                                       EmitBoolExpression (ec, sl.ConditionStart, sLabel, false);
+                                                       EmitBoolExpression (ec, sl.ConditionEnd, sLabel, false);
+                                                       ig.Emit (OpCodes.Br, lLabel);
+                                               } else {
+                                                       Label newLabel = ig.DefineLabel ();
+                                                       EmitBoolExpression (ec, sl.ConditionStart, newLabel, false);
+                                                       EmitBoolExpression (ec, sl.ConditionEnd, newLabel, false);
+                                                       ig.Emit (OpCodes.Br, lLabel);
+                                                       ig.MarkLabel (newLabel);
+                                               }
+                                               break;
+                                       case SwitchLabel.LabelType.Else :
+                                               // Nothing to be done here
+                                               break;
+                                       case SwitchLabel.LabelType.Operator :
+                                               EmitBoolExpression (ec, sl.ConditionLabel, lLabel, true);
+                                               if (labelIndex + 1 == Labels.Count)
+                                                       ig.Emit (OpCodes.Br, sLabel);
+                                               break;
+                                       case SwitchLabel.LabelType.Label :
+                                               EmitBoolExpression (ec, sl.ConditionLabel, lLabel, true);
+                                               if (labelIndex + 1 == Labels.Count)
+                                                       ig.Emit (OpCodes.Br, sLabel);
+                                               break;
+                                       }
+
+                               }
+                               ig.MarkLabel (lLabel);
+                               section.Block.Emit (ec);
+                               ig.MarkLabel (sLabel);
+                       }
 
                        // Restore context state. 
                        ig.MarkLabel (ec.LoopEnd);
@@ -2034,8 +4520,7 @@ namespace Mono.CSharp {
                        //
                        ec.LoopEnd = old_end;
                        ec.Switch = old_switch;
-                       
-                       return all_return;
+                       return true;
                }
        }
 
@@ -2056,15 +4541,15 @@ namespace Mono.CSharp {
                        return Statement.Resolve (ec) && expr != null;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        Type type = expr.Type;
                        bool val;
                        
                        if (type.IsValueType){
-                               Report.Error (185, loc, "lock statement requires the expression to be " +
+                               Report.Error (30582, loc, "lock statement requires the expression to be " +
                                              " a reference type (type is: `" +
-                                             TypeManager.CSharpName (type) + "'");
+                                             TypeManager.MonoBASIC_Name (type) + "'");
                                return false;
                        }
 
@@ -2077,7 +4562,7 @@ namespace Mono.CSharp {
                        ig.Emit (OpCodes.Call, TypeManager.void_monitor_enter_object);
 
                        // try
-                       Label end = ig.BeginExceptionBlock ();
+                       ig.BeginExceptionBlock ();
                        bool old_in_try = ec.InTry;
                        ec.InTry = true;
                        Label finish = ig.DefineLabel ();
@@ -2110,7 +4595,7 @@ namespace Mono.CSharp {
                        return Block.Resolve (ec);
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        bool previous_state = ec.CheckState;
                        bool previous_state_const = ec.ConstantCheckState;
@@ -2148,7 +4633,7 @@ namespace Mono.CSharp {
                        return ret;
                }
 
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        bool previous_state = ec.CheckState;
                        bool previous_state_const = ec.ConstantCheckState;
@@ -2174,10 +4659,17 @@ namespace Mono.CSharp {
 
                public override bool Resolve (EmitContext ec)
                {
-                       return Block.Resolve (ec);
+                       bool previous_state = ec.InUnsafe;
+                       bool val;
+                       
+                       ec.InUnsafe = true;
+                       val = Block.Resolve (ec);
+                       ec.InUnsafe = previous_state;
+
+                       return val;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        bool previous_state = ec.InUnsafe;
                        bool val;
@@ -2194,11 +4686,20 @@ namespace Mono.CSharp {
        // Fixed statement
        //
        public class Fixed : Statement {
-               string    type;
+               Expression type;
                ArrayList declarators;
                Statement statement;
+               Type expr_type;
+               FixedData[] data;
+
+               struct FixedData {
+                       public bool is_object;
+                       public VariableInfo vi;
+                       public Expression expr;
+                       public Expression converted;
+               }                       
 
-               public Fixed (string type, ArrayList decls, Statement stmt, Location l)
+               public Fixed (Expression type, ArrayList decls, Statement stmt, Location l)
                {
                        this.type = type;
                        declarators = decls;
@@ -2208,24 +4709,19 @@ namespace Mono.CSharp {
 
                public override bool Resolve (EmitContext ec)
                {
-                       return statement.Resolve (ec);
-               }
-               
-               public override bool Emit (EmitContext ec)
-               {
-                       ILGenerator ig = ec.ig;
-                       Type t;
-                       
-                       t = RootContext.LookupType (ec.DeclSpace, type, false, loc);
-                       if (t == null)
+                       expr_type = ec.DeclSpace.ResolveType (type, false, loc);
+                       if (expr_type == null)
                                return false;
 
-                       bool is_ret = false;
+                       data = new FixedData [declarators.Count];
 
+                       int i = 0;
                        foreach (Pair p in declarators){
                                VariableInfo vi = (VariableInfo) p.First;
                                Expression e = (Expression) p.Second;
 
+                               vi.Number = -1;
+
                                //
                                // The rules for the possible declarators are pretty wise,
                                // but the production on the grammar is more concise.
@@ -2250,37 +4746,30 @@ namespace Mono.CSharp {
                                                        "No need to use fixed statement for parameters or " +
                                                        "local variable declarations (address is already " +
                                                        "fixed)");
-                                               continue;
+                                               return false;
                                        }
                                        
                                        e = e.Resolve (ec);
                                        if (e == null)
-                                               continue;
+                                               return false;
 
                                        child = ((Unary) e).Expr;
                                        
                                        if (!TypeManager.VerifyUnManaged (child.Type, loc))
-                                               continue;
-
-                                       //
-                                       // Store pointer in pinned location
-                                       //
-                                       e.Emit (ec);
-                                       ig.Emit (OpCodes.Stloc, vi.LocalBuilder);
-
-                                       is_ret = statement.Emit (ec);
+                                               return false;
 
-                                       // Clear the pinned variable.
-                                       ig.Emit (OpCodes.Ldc_I4_0);
-                                       ig.Emit (OpCodes.Conv_U);
-                                       ig.Emit (OpCodes.Stloc, vi.LocalBuilder);
+                                       data [i].is_object = true;
+                                       data [i].expr = e;
+                                       data [i].converted = null;
+                                       data [i].vi = vi;
+                                       i++;
 
                                        continue;
                                }
 
                                e = e.Resolve (ec);
                                if (e == null)
-                                       continue;
+                                       return false;
 
                                //
                                // Case 2: Array
@@ -2293,23 +4782,80 @@ namespace Mono.CSharp {
                                        // Provided that array_type is unmanaged,
                                        //
                                        if (!TypeManager.VerifyUnManaged (array_type, loc))
-                                               continue;
+                                               return false;
 
                                        //
                                        // and T* is implicitly convertible to the
                                        // pointer type given in the fixed statement.
                                        //
-                                       ArrayPtr array_ptr = new ArrayPtr (e);
+                                       ArrayPtr array_ptr = new ArrayPtr (e, loc);
                                        
                                        Expression converted = Expression.ConvertImplicitRequired (
                                                ec, array_ptr, vi.VariableType, loc);
                                        if (converted == null)
-                                               continue;
+                                               return false;
+
+                                       data [i].is_object = false;
+                                       data [i].expr = e;
+                                       data [i].converted = converted;
+                                       data [i].vi = vi;
+                                       i++;
+
+                                       continue;
+                               }
+
+                               //
+                               // Case 3: string
+                               //
+                               if (e.Type == TypeManager.string_type){
+                                       data [i].is_object = false;
+                                       data [i].expr = e;
+                                       data [i].converted = null;
+                                       data [i].vi = vi;
+                                       i++;
+                               }
+                       }
+
+                       return statement.Resolve (ec);
+               }
+               
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       ILGenerator ig = ec.ig;
 
+                       bool is_ret = false;
+
+                       for (int i = 0; i < data.Length; i++) {
+                               VariableInfo vi = data [i].vi;
+
+                               //
+                               // Case 1: & object.
+                               //
+                               if (data [i].is_object) {
                                        //
                                        // Store pointer in pinned location
                                        //
-                                       converted.Emit (ec);
+                                       data [i].expr.Emit (ec);
+                                       ig.Emit (OpCodes.Stloc, vi.LocalBuilder);
+
+                                       is_ret = statement.Emit (ec);
+
+                                       // Clear the pinned variable.
+                                       ig.Emit (OpCodes.Ldc_I4_0);
+                                       ig.Emit (OpCodes.Conv_U);
+                                       ig.Emit (OpCodes.Stloc, vi.LocalBuilder);
+
+                                       continue;
+                               }
+
+                               //
+                               // Case 2: Array
+                               //
+                               if (data [i].expr.Type.IsArray){
+                                       //
+                                       // Store pointer in pinned location
+                                       //
+                                       data [i].converted.Emit (ec);
                                        
                                        ig.Emit (OpCodes.Stloc, vi.LocalBuilder);
 
@@ -2326,14 +4872,14 @@ namespace Mono.CSharp {
                                //
                                // Case 3: string
                                //
-                               if (e.Type == TypeManager.string_type){
+                               if (data [i].expr.Type == TypeManager.string_type){
                                        LocalBuilder pinned_string = ig.DeclareLocal (TypeManager.string_type);
                                        TypeManager.MakePinned (pinned_string);
                                        
-                                       e.Emit (ec);
+                                       data [i].expr.Emit (ec);
                                        ig.Emit (OpCodes.Stloc, pinned_string);
 
-                                       Expression sptr = new StringPtr (pinned_string);
+                                       Expression sptr = new StringPtr (pinned_string, loc);
                                        Expression converted = Expression.ConvertImplicitRequired (
                                                ec, sptr, vi.VariableType, loc);
                                        
@@ -2356,18 +4902,64 @@ namespace Mono.CSharp {
        }
        
        public class Catch {
-               public readonly string Type;
                public readonly string Name;
                public readonly Block  Block;
+               public Expression Clause;
                public readonly Location Location;
+
+               Expression type_expr;
+               //Expression clus_expr;
+               Type type;
                
-               public Catch (string type, string name, Block block, Location l)
+               public Catch (Expression type, string name, Block block, Expression clause, Location l)
                {
-                       Type = type;
+                       type_expr = type;
                        Name = name;
                        Block = block;
+                       Clause = clause;
                        Location = l;
                }
+
+               public Type CatchType {
+                       get {
+                               return type;
+                       }
+               }
+
+               public bool IsGeneral {
+                       get {
+                               return type_expr == null;
+                       }
+               }
+
+               public bool Resolve (EmitContext ec)
+               {
+                       if (type_expr != null) {
+                               type = ec.DeclSpace.ResolveType (type_expr, false, Location);
+                               if (type == null)
+                                       return false;
+
+                               if (type != TypeManager.exception_type && !type.IsSubclassOf (TypeManager.exception_type)){
+                                       Report.Error (30665, Location,
+                                                     "The type caught or thrown must be derived " +
+                                                     "from System.Exception");
+                                       return false;
+                               }
+                       } else
+                               type = null;
+
+                       if (Clause != null)     {
+                               Clause = Statement.ResolveBoolean (ec, Clause, Location);
+                               if (Clause == null) {
+                                       return false;
+                               }
+                       }
+
+                       if (!Block.Resolve (ec))
+                               return false;
+
+                       return true;
+               }
        }
 
        public class Try : Statement {
@@ -2378,7 +4970,7 @@ namespace Mono.CSharp {
                //
                // specific, general and fini might all be null.
                //
-               public Try (Block block, ArrayList specific, Catch general, Block fini)
+               public Try (Block block, ArrayList specific, Catch general, Block fini, Location l)
                {
                        if (specific == null && general == null){
                                Console.WriteLine ("CIR.Try: Either specific or general have to be non-null");
@@ -2388,39 +4980,110 @@ namespace Mono.CSharp {
                        this.Specific = specific;
                        this.General = general;
                        this.Fini = fini;
+                       loc = l;
                }
 
                public override bool Resolve (EmitContext ec)
                {
                        bool ok = true;
                        
-                       if (General != null)
-                               if (!General.Block.Resolve (ec))
-                                       ok = false;
+                       ec.StartFlowBranching (FlowBranchingType.EXCEPTION, Block.StartLocation);
+
+                       Report.Debug (1, "START OF TRY BLOCK", Block.StartLocation);
+
+                       bool old_in_try = ec.InTry;
+                       ec.InTry = true;
+
+                       if (!Block.Resolve (ec))
+                               ok = false;
+
+                       ec.InTry = old_in_try;
+
+                       FlowBranching.UsageVector vector = ec.CurrentBranching.CurrentUsageVector;
+
+                       Report.Debug (1, "START OF CATCH BLOCKS", vector);
 
                        foreach (Catch c in Specific){
-                               if (!c.Block.Resolve (ec))
+                               ec.CurrentBranching.CreateSibling ();
+                               Report.Debug (1, "STARTED SIBLING FOR CATCH", ec.CurrentBranching);
+
+                               if (c.Name != null) {
+                                       VariableInfo vi = c.Block.GetVariableInfo (c.Name);
+                                       if (vi == null)
+                                               throw new Exception ();
+
+                                       vi.Number = -1;
+                               }
+
+                               bool old_in_catch = ec.InCatch;
+                               ec.InCatch = true;
+
+                               if (!c.Resolve (ec))
                                        ok = false;
+
+                               ec.InCatch = old_in_catch;
+
+                               FlowBranching.UsageVector current = ec.CurrentBranching.CurrentUsageVector;
+
+                               if (!current.AlwaysReturns && !current.AlwaysBreaks)
+                                       vector.AndLocals (current);
                        }
 
-                       if (!Block.Resolve (ec))
-                               ok = false;
+                       Report.Debug (1, "END OF CATCH BLOCKS", ec.CurrentBranching);
+
+                       if (General != null){
+                               ec.CurrentBranching.CreateSibling ();
+                               Report.Debug (1, "STARTED SIBLING FOR GENERAL", ec.CurrentBranching);
+
+                               bool old_in_catch = ec.InCatch;
+                               ec.InCatch = true;
+
+                               if (!General.Resolve (ec))
+                                       ok = false;
+
+                               ec.InCatch = old_in_catch;
+
+                               FlowBranching.UsageVector current = ec.CurrentBranching.CurrentUsageVector;
+
+                               if (!current.AlwaysReturns && !current.AlwaysBreaks)
+                                       vector.AndLocals (current);
+                       }
+
+                       Report.Debug (1, "END OF GENERAL CATCH BLOCKS", ec.CurrentBranching);
+
+                       if (Fini != null) {
+                               ec.CurrentBranching.CreateSiblingForFinally ();
+                               Report.Debug (1, "STARTED SIBLING FOR FINALLY", ec.CurrentBranching, vector);
+
+                               bool old_in_finally = ec.InFinally;
+                               ec.InFinally = true;
 
-                       if (Fini != null)
                                if (!Fini.Resolve (ec))
                                        ok = false;
-                       
+
+                               ec.InFinally = old_in_finally;
+                       }
+
+                       FlowReturns returns = ec.EndFlowBranching ();
+
+                       FlowBranching.UsageVector f_vector = ec.CurrentBranching.CurrentUsageVector;
+
+                       Report.Debug (1, "END OF FINALLY", ec.CurrentBranching, returns, vector, f_vector);
+                       ec.CurrentBranching.CurrentUsageVector.Or (vector);
+
+                       Report.Debug (1, "END OF TRY", ec.CurrentBranching);
+
                        return ok;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
                        ILGenerator ig = ec.ig;
-                       Label end;
                        Label finish = ig.DefineLabel ();;
                        bool returns;
-                       
-                       end = ig.BeginExceptionBlock ();
+
+                       ec.TryCatchLevel++;
+                       ig.BeginExceptionBlock ();
                        bool old_in_try = ec.InTry;
                        ec.InTry = true;
                        returns = Block.Emit (ec);
@@ -2432,38 +5095,62 @@ namespace Mono.CSharp {
 
                        bool old_in_catch = ec.InCatch;
                        ec.InCatch = true;
-                       DeclSpace ds = ec.DeclSpace;
+                       //DeclSpace ds = ec.DeclSpace;
 
                        foreach (Catch c in Specific){
-                               Type catch_type = RootContext.LookupType (ds, c.Type, false, c.Location);
                                VariableInfo vi;
                                
-                               if (catch_type == null)
-                                       return false;
-
-                               ig.BeginCatchBlock (catch_type);
+                               ig.BeginCatchBlock (c.CatchType);
 
                                if (c.Name != null){
                                        vi = c.Block.GetVariableInfo (c.Name);
-                                       if (vi == null){
-                                               Console.WriteLine ("This should not happen! variable does not exist in this block");
-                                               Environment.Exit (0);
-                                       }
-                               
+                                       if (vi == null)
+                                               throw new Exception ("Variable does not exist in this block");
+
                                        ig.Emit (OpCodes.Stloc, vi.LocalBuilder);
                                } else
                                        ig.Emit (OpCodes.Pop);
-                               
-                               if (!c.Block.Emit (ec))
-                                       returns = false;
+
+                               //
+                               // if when clause is there
+                               //
+                               if (c.Clause != null) {
+                                       if (c.Clause is BoolConstant) {
+                                               bool take = ((BoolConstant) c.Clause).Value;
+
+                                               if (take) 
+                                                       if (!c.Block.Emit (ec))
+                                                               returns = false;
+                                       } else {
+                                               EmitBoolExpression (ec, c.Clause, finish, false);
+                                               if (!c.Block.Emit (ec))
+                                                       returns = false;
+                                       }
+                               } else 
+                                       if (!c.Block.Emit (ec))
+                                               returns = false;
                        }
 
                        if (General != null){
                                ig.BeginCatchBlock (TypeManager.object_type);
                                ig.Emit (OpCodes.Pop);
-                               if (!General.Block.Emit (ec))
-                                       returns = false;
+
+                               if (General.Clause != null) {
+                                       if (General.Clause is BoolConstant) {
+                                               bool take = ((BoolConstant) General.Clause).Value;
+                                               if (take) 
+                                                       if (!General.Block.Emit (ec))
+                                                               returns = false;
+                                       } else {
+                                               EmitBoolExpression (ec, General.Clause, finish, false);
+                                               if (!General.Block.Emit (ec))
+                                                       returns = false;
+                                       }
+                               } else 
+                                       if (!General.Block.Emit (ec))
+                                               returns = false;
                        }
+
                        ec.InCatch = old_in_catch;
 
                        ig.MarkLabel (finish);
@@ -2476,23 +5163,33 @@ namespace Mono.CSharp {
                        }
                        
                        ig.EndExceptionBlock ();
+                       ec.TryCatchLevel--;
 
-                       //
-                       // FIXME: Is this correct?
-                       // Replace with `returns' and check test-18, maybe we can
-                       // perform an optimization here.
-                       //
-                       return returns;
+                       if (!returns || ec.InTry || ec.InCatch)
+                               return returns;
+
+                       // Unfortunately, System.Reflection.Emit automatically emits a leave
+                       // to the end of the finally block.  This is a problem if `returns'
+                       // is true since we may jump to a point after the end of the method.
+                       // As a workaround, emit an explicit ret here.
+
+                       if (ec.ReturnType != null)
+                               ec.ig.Emit (OpCodes.Ldloc, ec.TemporaryReturn ());
+                       ec.ig.Emit (OpCodes.Ret);
+
+                       return true;
                }
        }
 
-       //
-       // FIXME: We still do not support the expression variant of the using
-       // statement.
-       //
        public class Using : Statement {
                object expression_or_block;
                Statement Statement;
+               ArrayList var_list;
+               Expression expr;
+               Type expr_type;
+               Expression conv;
+               Expression [] converted_vars;
+               ExpressionStatement [] assign;
                
                public Using (object expression_or_block, Statement stmt, Location l)
                {
@@ -2502,33 +5199,32 @@ namespace Mono.CSharp {
                }
 
                //
-               // Emits the code for the case of using using a local variable declaration.
+               // Resolves for the case of using using a local variable declaration.
                //
-               bool EmitLocalVariableDecls (EmitContext ec, string type_name, ArrayList var_list)
+               bool ResolveLocalVariableDecls (EmitContext ec)
                {
-                       ILGenerator ig = ec.ig;
-                       Expression [] converted_vars;
                        bool need_conv = false;
-                       Type type = RootContext.LookupType (ec.DeclSpace, type_name, false, loc);
+                       expr_type = ec.DeclSpace.ResolveType (expr, false, loc);
                        int i = 0;
 
-                       if (type == null)
+                       if (expr_type == null)
                                return false;
-                       
+
                        //
                        // The type must be an IDisposable or an implicit conversion
                        // must exist.
                        //
                        converted_vars = new Expression [var_list.Count];
-                       if (!TypeManager.ImplementsInterface (type, TypeManager.idisposable_type)){
+                       assign = new ExpressionStatement [var_list.Count];
+                       if (!TypeManager.ImplementsInterface (expr_type, TypeManager.idisposable_type)){
                                foreach (DictionaryEntry e in var_list){
                                        Expression var = (Expression) e.Key;
 
-                                       var = var.Resolve (ec);
+                                       var = var.ResolveLValue (ec, new EmptyExpression ());
                                        if (var == null)
                                                return false;
                                        
-                                       converted_vars [i] = Expression.ConvertImplicit (
+                                       converted_vars [i] = Expression.ConvertImplicitRequired (
                                                ec, var, TypeManager.idisposable_type, loc);
 
                                        if (converted_vars [i] == null)
@@ -2537,32 +5233,55 @@ namespace Mono.CSharp {
                                }
                                need_conv = true;
                        }
-                       
+
                        i = 0;
-                       bool old_in_try = ec.InTry;
-                       ec.InTry = true;
-                       bool error = false;
                        foreach (DictionaryEntry e in var_list){
                                LocalVariableReference var = (LocalVariableReference) e.Key;
-                               Expression expr = (Expression) e.Value;
+                               Expression new_expr = (Expression) e.Value;
                                Expression a;
 
-                               a = new Assign (var, expr, loc);
+                               a = new Assign (var, new_expr, loc);
                                a = a.Resolve (ec);
+                               if (a == null)
+                                       return false;
+
                                if (!need_conv)
                                        converted_vars [i] = var;
+                               assign [i] = (ExpressionStatement) a;
                                i++;
-                               if (a == null){
-                                       error = true;
-                                       continue;
-                               }
-                               ((ExpressionStatement) a).EmitStatement (ec);
+                       }
+
+                       return true;
+               }
+
+               bool ResolveExpression (EmitContext ec)
+               {
+                       if (!TypeManager.ImplementsInterface (expr_type, TypeManager.idisposable_type)){
+                               conv = Expression.ConvertImplicitRequired (
+                                       ec, expr, TypeManager.idisposable_type, loc);
+
+                               if (conv == null)
+                                       return false;
+                       }
+
+                       return true;
+               }
+               
+               //
+               // Emits the code for the case of using using a local variable declaration.
+               //
+               bool EmitLocalVariableDecls (EmitContext ec)
+               {
+                       ILGenerator ig = ec.ig;
+                       int i = 0;
+
+                       bool old_in_try = ec.InTry;
+                       ec.InTry = true;
+                       for (i = 0; i < assign.Length; i++) {
+                               assign [i].EmitStatement (ec);
                                
                                ig.BeginExceptionBlock ();
-
                        }
-                       if (error)
-                               return false;
                        Statement.Emit (ec);
                        ec.InTry = old_in_try;
 
@@ -2588,19 +5307,8 @@ namespace Mono.CSharp {
                        return false;
                }
 
-               bool EmitExpression (EmitContext ec, Expression expr)
+               bool EmitExpression (EmitContext ec)
                {
-                       Type expr_type = expr.Type;
-                       Expression conv = null;
-                       
-                       if (!TypeManager.ImplementsInterface (expr_type, TypeManager.idisposable_type)){
-                               conv = Expression.ConvertImplicit (
-                                       ec, expr, TypeManager.idisposable_type, loc);
-
-                               if (conv == null)
-                                       return false;
-                       }
-
                        //
                        // Make a copy of the expression and operate on that.
                        //
@@ -2634,42 +5342,64 @@ namespace Mono.CSharp {
                
                public override bool Resolve (EmitContext ec)
                {
+                       if (expression_or_block is DictionaryEntry){
+                               expr = (Expression) ((DictionaryEntry) expression_or_block).Key;
+                               var_list = (ArrayList)((DictionaryEntry)expression_or_block).Value;
+
+                               if (!ResolveLocalVariableDecls (ec))
+                                       return false;
+
+                       } else if (expression_or_block is Expression){
+                               expr = (Expression) expression_or_block;
+
+                               expr = expr.Resolve (ec);
+                               if (expr == null)
+                                       return false;
+
+                               expr_type = expr.Type;
+
+                               if (!ResolveExpression (ec))
+                                       return false;
+                       }                       
+
                        return Statement.Resolve (ec);
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
-                       if (expression_or_block is DictionaryEntry){
-                               string t = (string) ((DictionaryEntry) expression_or_block).Key;
-                               ArrayList var_list = (ArrayList)((DictionaryEntry)expression_or_block).Value;
-
-                               return EmitLocalVariableDecls (ec, t, var_list);
-                       } if (expression_or_block is Expression){
-                               Expression e = (Expression) expression_or_block;
-
-                               e = e.Resolve (ec);
-                               if (e == null)
-                                       return false;
+                       if (expression_or_block is DictionaryEntry)
+                               return EmitLocalVariableDecls (ec);
+                       else if (expression_or_block is Expression)
+                               return EmitExpression (ec);
 
-                               return EmitExpression (ec, e);
-                       }
                        return false;
                }
        }
 
        /// <summary>
-       ///   Implementation of the foreach C# statement
+       ///   Implementation of the for each statement
        /// </summary>
        public class Foreach : Statement {
-               string type;
+               Expression type;
                LocalVariableReference variable;
                Expression expr;
                Statement statement;
+               ForeachHelperMethods hm;
+               Expression empty, conv;
+               Type array_type, element_type;
+               Type var_type;
                
-               public Foreach (string type, LocalVariableReference var, Expression expr,
+               public Foreach (Expression type, LocalVariableReference var, Expression expr,
                                Statement stmt, Location l)
                {
-                       this.type = type;
+                       if (type != null) {
+                               this.type = type;
+                       }
+                       else
+                       {
+                               VariableInfo vi = var.VariableInfo;
+                               this.type = vi.Type;
+                       }
                        this.variable = var;
                        this.expr = expr;
                        statement = stmt;
@@ -2677,9 +5407,70 @@ namespace Mono.CSharp {
                }
                
                public override bool Resolve (EmitContext ec)
-               {
+               {       
                        expr = expr.Resolve (ec);
-                       return statement.Resolve (ec) && expr != null;
+                       if (expr == null)
+                               return false;
+
+                       var_type = ec.DeclSpace.ResolveType (type, false, loc);
+                       if (var_type == null)
+                               return false;
+                       
+                       //
+                       // We need an instance variable.  Not sure this is the best
+                       // way of doing this.
+                       //
+                       // FIXME: When we implement propertyaccess, will those turn
+                       // out to return values in ExprClass?  I think they should.
+                       //
+                       if (!(expr.eclass == ExprClass.Variable || expr.eclass == ExprClass.Value ||
+                             expr.eclass == ExprClass.PropertyAccess || expr.eclass == ExprClass.IndexerAccess)){
+                               error1579 (expr.Type);
+                               return false;
+                       }
+
+                       if (expr.Type.IsArray) {
+                               array_type = expr.Type;
+                               element_type = array_type.GetElementType ();
+
+                               empty = new EmptyExpression (element_type);
+                       } else {
+                               hm = ProbeCollectionType (ec, expr.Type);
+                               if (hm == null){
+                                       error1579 (expr.Type);
+                                       return false;
+                               }
+
+                               array_type = expr.Type;
+                               element_type = hm.element_type;
+
+                               empty = new EmptyExpression (hm.element_type);
+                       }
+
+                       ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+                       ec.CurrentBranching.CreateSibling ();
+
+                       //
+                       //
+                       // FIXME: maybe we can apply the same trick we do in the
+                       // array handling to avoid creating empty and conv in some cases.
+                       //
+                       // Although it is not as important in this case, as the type
+                       // will not likely be object (what the enumerator will return).
+                       //
+                       conv = Expression.ConvertExplicit (ec, empty, var_type, false, loc);
+                       if (conv == null)
+                               return false;
+
+                       if (variable.ResolveLValue (ec, empty) == null)
+                               return false;
+                       
+                       if (!statement.Resolve (ec))
+                               return false;
+
+                       //FlowReturns returns = ec.EndFlowBranching ();
+                       ec.EndFlowBranching ();
+                       return true;
                }
                
                //
@@ -2687,13 +5478,13 @@ namespace Mono.CSharp {
                //
                static MethodInfo FetchMethodMoveNext (Type t)
                {
-                       MemberInfo [] move_next_list;
+                       MemberList move_next_list;
                        
                        move_next_list = TypeContainer.FindMembers (
                                t, MemberTypes.Method,
                                BindingFlags.Public | BindingFlags.Instance,
                                Type.FilterName, "MoveNext");
-                       if (move_next_list == null || move_next_list.Length == 0)
+                       if (move_next_list.Count == 0)
                                return null;
 
                        foreach (MemberInfo m in move_next_list){
@@ -2714,19 +5505,19 @@ namespace Mono.CSharp {
                //
                static MethodInfo FetchMethodGetCurrent (Type t)
                {
-                       MemberInfo [] move_next_list;
+                       MemberList move_next_list;
                        
                        move_next_list = TypeContainer.FindMembers (
                                t, MemberTypes.Method,
                                BindingFlags.Public | BindingFlags.Instance,
                                Type.FilterName, "get_Current");
-                       if (move_next_list == null || move_next_list.Length == 0)
+                       if (move_next_list.Count == 0)
                                return null;
 
                        foreach (MemberInfo m in move_next_list){
                                MethodInfo mi = (MethodInfo) m;
                                Type [] args;
-                               
+
                                args = TypeManager.GetArgumentTypes (mi);
                                if (args != null && args.Length == 0)
                                        return mi;
@@ -2742,10 +5533,16 @@ namespace Mono.CSharp {
                        public MethodInfo get_enumerator;
                        public MethodInfo move_next;
                        public MethodInfo get_current;
+                       public Type element_type;
+                       public Type enumerator_type;
+                       public bool is_disposable;
 
                        public ForeachHelperMethods (EmitContext ec)
                        {
                                this.ec = ec;
+                               this.element_type = TypeManager.object_type;
+                               this.enumerator_type = TypeManager.ienumerator_type;
+                               this.is_disposable = true;
                        }
                }
                
@@ -2768,7 +5565,7 @@ namespace Mono.CSharp {
                        }
                        ForeachHelperMethods hm = (ForeachHelperMethods) criteria;
                        EmitContext ec = hm.ec;
-                       
+
                        //
                        // Check whether GetEnumerator is accessible to us
                        //
@@ -2804,8 +5601,10 @@ namespace Mono.CSharp {
                        // Ok, we can access it, now make sure that we can do something
                        // with this `GetEnumerator'
                        //
-                       if (mi.ReturnType == TypeManager.ienumerator_type || 
-                           TypeManager.ienumerator_type.IsAssignableFrom (mi.ReturnType)){
+
+                       if (mi.ReturnType == TypeManager.ienumerator_type ||
+                           TypeManager.ienumerator_type.IsAssignableFrom (mi.ReturnType) ||
+                           (!RootContext.StdLib && TypeManager.ImplementsInterface (mi.ReturnType, TypeManager.ienumerator_type))) {
                                hm.move_next = TypeManager.bool_movenext_void;
                                hm.get_current = TypeManager.object_getcurrent_void;
                                return true;
@@ -2824,6 +5623,11 @@ namespace Mono.CSharp {
                        if (hm.get_current == null)
                                return false;
 
+                       hm.element_type = hm.get_current.ReturnType;
+                       hm.enumerator_type = return_type;
+                       hm.is_disposable = TypeManager.ImplementsInterface (
+                               hm.enumerator_type, TypeManager.idisposable_type);
+
                        return true;
                }
                
@@ -2848,14 +5652,14 @@ namespace Mono.CSharp {
 
                static bool TryType (Type t, ForeachHelperMethods hm)
                {
-                       MemberInfo [] mi;
+                       MemberList mi;
                        
                        mi = TypeContainer.FindMembers (t, MemberTypes.Method,
                                                        BindingFlags.Public | BindingFlags.NonPublic |
                                                        BindingFlags.Instance,
                                                        FilterEnumerator, hm);
 
-                       if (mi == null || mi.Length == 0)
+                       if (mi.Count == 0)
                                return false;
 
                        hm.get_enumerator = (MethodInfo) mi [0];
@@ -2903,26 +5707,16 @@ namespace Mono.CSharp {
                // FIXME: possible optimization.
                // We might be able to avoid creating `empty' if the type is the sam
                //
-               bool EmitCollectionForeach (EmitContext ec, Type var_type, ForeachHelperMethods hm)
+               bool EmitCollectionForeach (EmitContext ec)
                {
                        ILGenerator ig = ec.ig;
                        LocalBuilder enumerator, disposable;
-                       Expression empty = new EmptyExpression ();
-                       Expression conv;
 
-                       //
-                       // FIXME: maybe we can apply the same trick we do in the
-                       // array handling to avoid creating empty and conv in some cases.
-                       //
-                       // Although it is not as important in this case, as the type
-                       // will not likely be object (what the enumerator will return).
-                       //
-                       conv = Expression.ConvertExplicit (ec, empty, var_type, loc);
-                       if (conv == null)
-                               return false;
-                       
-                       enumerator = ig.DeclareLocal (TypeManager.ienumerator_type);
-                       disposable = ig.DeclareLocal (TypeManager.idisposable_type);
+                       enumerator = ig.DeclareLocal (hm.enumerator_type);
+                       if (hm.is_disposable)
+                               disposable = ig.DeclareLocal (TypeManager.idisposable_type);
+                       else
+                               disposable = null;
                        
                        //
                        // Instantiate the enumerator
@@ -2946,9 +5740,12 @@ namespace Mono.CSharp {
                        // Protect the code in a try/finalize block, so that
                        // if the beast implement IDisposable, we get rid of it
                        //
-                       Label l = ig.BeginExceptionBlock ();
                        bool old_in_try = ec.InTry;
-                       ec.InTry = true;
+
+                       if (hm.is_disposable) {
+                               ig.BeginExceptionBlock ();
+                               ec.InTry = true;
+                       }
                        
                        Label end_try = ig.DefineLabel ();
                        
@@ -2970,25 +5767,27 @@ namespace Mono.CSharp {
                        //
                        // Now the finally block
                        //
-                       Label end_finally = ig.DefineLabel ();
-                       bool old_in_finally = ec.InFinally;
-                       ec.InFinally = true;
-                       ig.BeginFinallyBlock ();
+                       if (hm.is_disposable) {
+                               Label end_finally = ig.DefineLabel ();
+                               bool old_in_finally = ec.InFinally;
+                               ec.InFinally = true;
+                               ig.BeginFinallyBlock ();
                        
-                       ig.Emit (OpCodes.Ldloc, enumerator);
-                       ig.Emit (OpCodes.Isinst, TypeManager.idisposable_type);
-                       ig.Emit (OpCodes.Stloc, disposable);
-                       ig.Emit (OpCodes.Ldloc, disposable);
-                       ig.Emit (OpCodes.Brfalse, end_finally);
-                       ig.Emit (OpCodes.Ldloc, disposable);
-                       ig.Emit (OpCodes.Callvirt, TypeManager.void_dispose_void);
-                       ig.MarkLabel (end_finally);
-                       ec.InFinally = old_in_finally;
+                               ig.Emit (OpCodes.Ldloc, enumerator);
+                               ig.Emit (OpCodes.Isinst, TypeManager.idisposable_type);
+                               ig.Emit (OpCodes.Stloc, disposable);
+                               ig.Emit (OpCodes.Ldloc, disposable);
+                               ig.Emit (OpCodes.Brfalse, end_finally);
+                               ig.Emit (OpCodes.Ldloc, disposable);
+                               ig.Emit (OpCodes.Callvirt, TypeManager.void_dispose_void);
+                               ig.MarkLabel (end_finally);
+                               ec.InFinally = old_in_finally;
 
-                       // The runtime generates this anyways.
-                       // ig.Emit (OpCodes.Endfinally);
+                               // The runtime generates this anyways.
+                               // ig.Emit (OpCodes.Endfinally);
 
-                       ig.EndExceptionBlock ();
+                               ig.EndExceptionBlock ();
+                       }
 
                        ig.MarkLabel (ec.LoopEnd);
                        return false;
@@ -2998,17 +5797,8 @@ namespace Mono.CSharp {
                // FIXME: possible optimization.
                // We might be able to avoid creating `empty' if the type is the sam
                //
-               bool EmitArrayForeach (EmitContext ec, Type var_type)
+               bool EmitArrayForeach (EmitContext ec)
                {
-                       Type array_type = expr.Type;
-                       Type element_type = array_type.GetElementType ();
-                       Expression conv = null;
-                       Expression empty = new EmptyExpression (element_type);
-                       
-                       conv = Expression.ConvertExplicit (ec, empty, var_type, loc);
-                       if (conv == null)
-                               return false;
-
                        int rank = array_type.GetArrayRank ();
                        ILGenerator ig = ec.ig;
 
@@ -3120,56 +5910,291 @@ namespace Mono.CSharp {
                        return false;
                }
                
-               public override bool Emit (EmitContext ec)
+               protected override bool DoEmit (EmitContext ec)
                {
-                       Type var_type;
                        bool ret_val;
                        
-                       var_type = RootContext.LookupType (ec.DeclSpace, type, false, loc);
-                       if (var_type == null)
-                               return false;
-                       
-                       //
-                       // We need an instance variable.  Not sure this is the best
-                       // way of doing this.
-                       //
-                       // FIXME: When we implement propertyaccess, will those turn
-                       // out to return values in ExprClass?  I think they should.
-                       //
-                       if (!(expr.eclass == ExprClass.Variable || expr.eclass == ExprClass.Value ||
-                             expr.eclass == ExprClass.PropertyAccess)){
-                               error1579 (expr.Type);
-                               return false;
-                       }
-
                        ILGenerator ig = ec.ig;
                        
                        Label old_begin = ec.LoopBegin, old_end = ec.LoopEnd;
                        bool old_inloop = ec.InLoop;
+                       int old_loop_begin_try_catch_level = ec.LoopBeginTryCatchLevel;
                        ec.LoopBegin = ig.DefineLabel ();
                        ec.LoopEnd = ig.DefineLabel ();
                        ec.InLoop = true;
+                       ec.LoopBeginTryCatchLevel = ec.TryCatchLevel;
                        
-                       if (expr.Type.IsArray)
-                               ret_val = EmitArrayForeach (ec, var_type);
-                       else {
-                               ForeachHelperMethods hm;
-                               
-                               hm = ProbeCollectionType (ec, expr.Type);
-                               if (hm == null){
-                                       error1579 (expr.Type);
-                                       return false;
-                               }
-
-                               ret_val = EmitCollectionForeach (ec, var_type, hm);
-                       }
+                       if (hm != null)
+                               ret_val = EmitCollectionForeach (ec);
+                       else
+                               ret_val = EmitArrayForeach (ec);
                        
                        ec.LoopBegin = old_begin;
                        ec.LoopEnd = old_end;
                        ec.InLoop = old_inloop;
+                       ec.LoopBeginTryCatchLevel = old_loop_begin_try_catch_level;
 
                        return ret_val;
                }
        }
-}
+       
+       /// <summary>
+       ///   AddHandler statement
+       /// </summary>
+       public class AddHandler : Statement {
+               Expression EvtId;
+               Expression EvtHandler;
+
+               //
+               // keeps track whether EvtId is already resolved
+               //
+               bool resolved;
+
+               public AddHandler (Expression evt_id, Expression evt_handler, Location l)
+               {
+                       EvtId = evt_id;
+                       EvtHandler = evt_handler;
+                       loc = l;
+                       resolved = false;
+                       //Console.WriteLine ("Adding handler '" + evt_handler + "' for Event '" + evt_id +"'");
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       //
+                       // if EvetId is of EventExpr type that means
+                       // this is already resolved 
+                       //
+                       if (EvtId is EventExpr) {
+                               resolved = true;
+                               return true;
+                       }
+
+                       EvtId = EvtId.Resolve(ec);
+                       EvtHandler = EvtHandler.Resolve(ec,ResolveFlags.MethodGroup);
+                       if (EvtId == null || (!(EvtId is EventExpr))) {
+                               Report.Error (30676, "Need an event designator.");
+                               return false;
+                       }
+
+                       if (EvtHandler == null) 
+                       {
+                               Report.Error (999, "'AddHandler' statement needs an event handler.");
+                               return false;
+                       }
+
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       //
+                       // Already resolved and emitted don't do anything
+                       //
+                       if (resolved)
+                               return true;
+
+                       Expression e, d;
+                       ArrayList args = new ArrayList();
+                       Argument arg = new Argument (EvtHandler, Argument.AType.Expression);
+                       args.Add (arg);
+                       
+                       
+
+                       // The even type was already resolved to a delegate, so
+                       // we must un-resolve its name to generate a type expression
+                       string ts = (EvtId.Type.ToString()).Replace ('+','.');
+                       Expression dtype = Mono.MonoBASIC.Parser.DecomposeQI (ts, Location.Null);
+
+                       // which we can use to declare a new event handler
+                       // of the same type
+                       d = new New (dtype, args, Location.Null);
+                       d = d.Resolve(ec);
+                       e = new CompoundAssign(Binary.Operator.Addition, EvtId, d, Location.Null);
+
+                       // we resolve it all and emit the code
+                       e = e.Resolve(ec);
+                       if (e != null) 
+                       {
+                               e.Emit(ec);
+                               return true;
+                       }
+
+                       return false;
+               }
+       }
+
+       /// <summary>
+       ///   RemoveHandler statement
+       /// </summary>
+       public class RemoveHandler : Statement \r
+       {
+               Expression EvtId;
+               Expression EvtHandler;
+
+               public RemoveHandler (Expression evt_id, Expression evt_handler, Location l)
+               {
+                       EvtId = evt_id;
+                       EvtHandler = evt_handler;
+                       loc = l;
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       EvtId = EvtId.Resolve(ec);
+                       EvtHandler = EvtHandler.Resolve(ec,ResolveFlags.MethodGroup);
+                       if (EvtId == null || (!(EvtId is EventExpr))) \r
+                       {
+                               Report.Error (30676, "Need an event designator.");
+                               return false;
+                       }
+
+                       if (EvtHandler == null) 
+                       {
+                               Report.Error (999, "'AddHandler' statement needs an event handler.");
+                               return false;
+                       }
+                       return true;
+               }
+
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       Expression e, d;
+                       ArrayList args = new ArrayList();
+                       Argument arg = new Argument (EvtHandler, Argument.AType.Expression);
+                       args.Add (arg);
+                       
+                       // The even type was already resolved to a delegate, so
+                       // we must un-resolve its name to generate a type expression
+                       string ts = (EvtId.Type.ToString()).Replace ('+','.');
+                       Expression dtype = Mono.MonoBASIC.Parser.DecomposeQI (ts, Location.Null);
+
+                       // which we can use to declare a new event handler
+                       // of the same type
+                       d = new New (dtype, args, Location.Null);
+                       d = d.Resolve(ec);
+                       // detach the event
+                       e = new CompoundAssign(Binary.Operator.Subtraction, EvtId, d, Location.Null);
+
+                       // we resolve it all and emit the code
+                       e = e.Resolve(ec);
+                       if (e != null) 
+                       {
+                               e.Emit(ec);
+                               return true;
+                       }
+
+                       return false;
+               }
+       }
+
+       public class RedimClause {
+               public Expression Expr;
+               public ArrayList NewIndexes;
+               
+               public RedimClause (Expression e, ArrayList args)
+               {
+                       Expr = e;
+                       NewIndexes = args;
+               }
+       }
+
+       public class ReDim : Statement {
+               ArrayList RedimTargets;
+               Type BaseType;
+               bool Preserve;
+
+               private StatementExpression ReDimExpr;
+
+               public ReDim (ArrayList targets, bool opt_preserve, Location l)
+               {
+                       loc = l;
+                       RedimTargets = targets;
+                       Preserve = opt_preserve;
+               }
+
+               public override bool Resolve (EmitContext ec)
+               {
+                       Expression RedimTarget;
+                       ArrayList NewIndexes;
+
+                       foreach (RedimClause rc in RedimTargets) {
+                               RedimTarget = rc.Expr;
+                               NewIndexes = rc.NewIndexes;
+
+                               RedimTarget = RedimTarget.Resolve (ec);
+                               if (!RedimTarget.Type.IsArray)
+                                       Report.Error (49, "'ReDim' statement requires an array");
+
+                               ArrayList args = new ArrayList();
+                               foreach (Argument a in NewIndexes) {
+                                       if (a.Resolve(ec, loc))
+                                               args.Add (a.Expr);
+                               }
+
+                               for (int x = 0; x < args.Count; x++) {
+                                       args[x] = new Binary (Binary.Operator.Addition,
+                                                               (Expression) args[x], new IntLiteral (1), Location.Null);       
+                               }
+
+                               NewIndexes = args;
+                               if (RedimTarget.Type.GetArrayRank() != args.Count)
+                                       Report.Error (30415, "'ReDim' cannot change the number of dimensions of an array.");
 
+                               BaseType = RedimTarget.Type.GetElementType();
+                               Expression BaseTypeExpr = MonoBASIC.Parser.DecomposeQI(BaseType.FullName.ToString(), Location.Null);
+                               ArrayCreation acExpr = new ArrayCreation (BaseTypeExpr, NewIndexes, "", null, Location.Null);   
+                               // TODO: we are in a foreach we probably can't reuse ReDimExpr, must turn it into an array(list)
+                               if (Preserve)
+                               {
+                                       ExpressionStatement PreserveExpr = (ExpressionStatement) new Preserve(RedimTarget, acExpr, loc);
+                                       ReDimExpr = (StatementExpression) new StatementExpression ((ExpressionStatement) new Assign (RedimTarget, PreserveExpr, loc), loc);
+                               }
+                               else
+                                       ReDimExpr = (StatementExpression) new StatementExpression ((ExpressionStatement) new Assign (RedimTarget, acExpr, loc), loc);
+                               ReDimExpr.Resolve(ec);
+                       }
+                       return true;
+               }
+                               
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       ReDimExpr.Emit(ec);
+                       return false;
+               }               
+               
+       }
+       
+       public class Erase : Statement {
+               Expression EraseTarget;
+               
+               private StatementExpression EraseExpr;
+               
+               public Erase (Expression expr, Location l)
+               {
+                       loc = l;
+                       EraseTarget = expr;
+               }
+               
+               public override bool Resolve (EmitContext ec)
+               {
+                       EraseTarget = EraseTarget.Resolve (ec);
+                       if (!EraseTarget.Type.IsArray) 
+                               Report.Error (49, "'Erase' statement requires an array");
+
+                       EraseExpr = (StatementExpression) new StatementExpression ((ExpressionStatement) new Assign (EraseTarget, NullLiteral.Null, loc), loc);
+                       EraseExpr.Resolve(ec);
+                       
+                       return true;
+               }
+                               
+               protected override bool DoEmit (EmitContext ec)
+               {
+                       EraseExpr.Emit(ec);
+                       return false;
+               }               
+               
+       }
+       
+       
+}