mcs/mcs/codegen.cs

   1 //
   2 // codegen.cs: The code generator
   3 //
   4 // Author:
   5 //   Miguel de Icaza (miguel@ximian.com)
   6 //
   7 // Copyright 2001, 2002, 2003 Ximian, Inc.
   8 // Copyright 2004 Novell, Inc.
   9 //
  10
  11 //
  12 // Please leave this defined on SVN: The idea is that when we ship the
  13 // compiler to end users, if the compiler crashes, they have a chance
  14 // to narrow down the problem.
  15 //
  16 // Only remove it if you need to debug locally on your tree.
  17 //
  18 #define PRODUCTION
  19
  20 using System;
  21 using System.IO;
  22 using System.Collections;
  23 using System.Collections.Specialized;
  24 using System.Globalization;
  25 using System.Reflection;
  26 using System.Reflection.Emit;
  27 using System.Runtime.InteropServices;
  28 using System.Security;
  29 using System.Security.Cryptography;
  30 using System.Security.Permissions;
  31
  32 using Mono.Security.Cryptography;
  33
  34 namespace Mono.CSharp {
  35
  36         /// <summary>
  37         ///    Code generator class.
  38         /// </summary>
  39         public class CodeGen {
  40                 static AppDomain current_domain;
  41
  42                 public static AssemblyClass Assembly;
  43                 public static ModuleClass Module;
  44
  45                 static CodeGen ()
  46                 {
  47                         Reset ();
  48                 }
  49
  50                 public static void Reset ()
  51                 {
  52                         Assembly = new AssemblyClass ();
  53                         Module = new ModuleClass (RootContext.Unsafe);
  54                 }
  55
  56                 public static string Basename (string name)
  57                 {
  58                         int pos = name.LastIndexOf ('/');
  59
  60                         if (pos != -1)
  61                                 return name.Substring (pos + 1);
  62
  63                         pos = name.LastIndexOf ('\\');
  64                         if (pos != -1)
  65                                 return name.Substring (pos + 1);
  66
  67                         return name;
  68                 }
  69
  70                 public static string Dirname (string name)
  71                 {
  72                         int pos = name.LastIndexOf ('/');
  73
  74                         if (pos != -1)
  75                                 return name.Substring (0, pos);
  76
  77                         pos = name.LastIndexOf ('\\');
  78                         if (pos != -1)
  79                                 return name.Substring (0, pos);
  80
  81                         return ".";
  82                 }
  83
  84                 static public string FileName;
  85
  86 #if MS_COMPATIBLE
  87                 const AssemblyBuilderAccess COMPILER_ACCESS = 0;
  88 #else
  89                 /* Keep this in sync with System.Reflection.Emit.AssemblyBuilder */
  90                 const AssemblyBuilderAccess COMPILER_ACCESS = (AssemblyBuilderAccess) 0x800;
  91 #endif
  92
  93                 //
  94                 // Initializes the code generator variables for interactive use (repl)
  95                 //
  96                 static public void InitDynamic (string name)
  97                 {
  98                         current_domain = AppDomain.CurrentDomain;
  99                         AssemblyName an = Assembly.GetAssemblyName (name, name);
 100
 101                         Assembly.Builder = current_domain.DefineDynamicAssembly (an, AssemblyBuilderAccess.Run | COMPILER_ACCESS);
 102                         Module.Builder = Assembly.Builder.DefineDynamicModule (Basename (name), false);
 103                 }
 104
 105                 //
 106                 // Initializes the code generator variables
 107                 //
 108                 static public bool Init (string name, string output, bool want_debugging_support)
 109                 {
 110                         FileName = output;
 111                         AssemblyName an = Assembly.GetAssemblyName (name, output);
 112                         if (an == null)
 113                                 return false;
 114
 115                         if (an.KeyPair != null) {
 116                                 // If we are going to strong name our assembly make
 117                                 // sure all its refs are strong named
 118                                 foreach (Assembly a in RootNamespace.Global.Assemblies) {
 119                                         AssemblyName ref_name = a.GetName ();
 120                                         byte [] b = ref_name.GetPublicKeyToken ();
 121                                         if (b == null || b.Length == 0) {
 122                                                 Report.Error (1577, "Assembly generation failed " +
 123                                                                 "-- Referenced assembly '" +
 124                                                                 ref_name.Name +
 125                                                                 "' does not have a strong name.");
 126                                                 //Environment.Exit (1);
 127                                         }
 128                                 }
 129                         }
 130
 131                         current_domain = AppDomain.CurrentDomain;
 132
 133                         try {
 134                                 Assembly.Builder = current_domain.DefineDynamicAssembly (an,
 135                                         AssemblyBuilderAccess.RunAndSave | COMPILER_ACCESS, Dirname (name));
 136                         }
 137                         catch (ArgumentException) {
 138                                 // specified key may not be exportable outside it's container
 139                                 if (RootContext.StrongNameKeyContainer != null) {
 140                                         Report.Error (1548, "Could not access the key inside the container `" +
 141                                                 RootContext.StrongNameKeyContainer + "'.");
 142                                         Environment.Exit (1);
 143                                 }
 144                                 throw;
 145                         }
 146                         catch (CryptographicException) {
 147                                 if ((RootContext.StrongNameKeyContainer != null) || (RootContext.StrongNameKeyFile != null)) {
 148                                         Report.Error (1548, "Could not use the specified key to strongname the assembly.");
 149                                         Environment.Exit (1);
 150                                 }
 151                                 return false;
 152                         }
 153
 154 #if GMCS_SOURCE
 155                         // Get the complete AssemblyName from the builder
 156                         // (We need to get the public key and token)
 157                         Assembly.Name = Assembly.Builder.GetName ();
 158 #endif
 159
 160                         //
 161                         // Pass a path-less name to DefineDynamicModule.  Wonder how
 162                         // this copes with output in different directories then.
 163                         // FIXME: figure out how this copes with --output /tmp/blah
 164                         //
 165                         // If the third argument is true, the ModuleBuilder will dynamically
 166                         // load the default symbol writer.
 167                         //
 168                         try {
 169                                 Module.Builder = Assembly.Builder.DefineDynamicModule (
 170                                         Basename (name), Basename (output), want_debugging_support);
 171
 172 #if !MS_COMPATIBLE
 173                                 // TODO: We should use SymbolWriter from DefineDynamicModule
 174                                 if (want_debugging_support && !SymbolWriter.Initialize (Module.Builder, output)) {
 175                                         Report.Error (40, "Unexpected debug information initialization error `{0}'",
 176                                                 "Could not find the symbol writer assembly (Mono.CompilerServices.SymbolWriter.dll)");
 177                                         return false;
 178                                 }
 179 #endif
 180                         } catch (ExecutionEngineException e) {
 181                                 Report.Error (40, "Unexpected debug information initialization error `{0}'",
 182                                         e.Message);
 183                                 return false;
 184                         }
 185
 186                         return true;
 187                 }
 188
 189                 static public void Save (string name, bool saveDebugInfo)
 190                 {
 191                         try {
 192                                 Assembly.Builder.Save (Basename (name));
 193                         }
 194                         catch (COMException) {
 195                                 if ((RootContext.StrongNameKeyFile == null) || (!RootContext.StrongNameDelaySign))
 196                                         throw;
 197
 198                                 // FIXME: it seems Microsoft AssemblyBuilder doesn't like to delay sign assemblies
 199                                 Report.Error (1548, "Couldn't delay-sign the assembly with the '" +
 200                                         RootContext.StrongNameKeyFile +
 201                                         "', Use MCS with the Mono runtime or CSC to compile this assembly.");
 202                         }
 203                         catch (System.IO.IOException io) {
 204                                 Report.Error (16, "Could not write to file `"+name+"', cause: " + io.Message);
 205                                 return;
 206                         }
 207                         catch (System.UnauthorizedAccessException ua) {
 208                                 Report.Error (16, "Could not write to file `"+name+"', cause: " + ua.Message);
 209                                 return;
 210                         }
 211
 212                         //
 213                         // Write debuger symbol file
 214                         //
 215                         if (saveDebugInfo)
 216                                 SymbolWriter.WriteSymbolFile ();
 217                         }
 218         }
 219
 220
 221         /// <summary>
 222         /// An interface to hold all the information needed in the resolving phase.
 223         /// </summary>
 224         public interface IResolveContext
 225         {
 226                 DeclSpace DeclContainer { get; }
 227                 bool IsInObsoleteScope { get; }
 228                 bool IsInUnsafeScope { get; }
 229
 230                 // the declcontainer to lookup for type-parameters.  Should only use LookupGeneric on it.
 231                 //
 232                 // FIXME: This is somewhat of a hack.  We don't need a full DeclSpace for this.  We just need the
 233                 //        current type parameters in scope. IUIC, that will require us to rewrite GenericMethod.
 234                 //        Maybe we can replace this with a 'LookupGeneric (string)' instead, but we'll have to
 235                 //        handle generic method overrides differently
 236                 DeclSpace GenericDeclContainer { get; }
 237         }
 238
 239         /// <summary>
 240         ///   An Emit Context is created for each body of code (from methods,
 241         ///   properties bodies, indexer bodies or constructor bodies)
 242         /// </summary>
 243         public class EmitContext : IResolveContext {
 244
 245                 //
 246                 // Holds a varible used during collection or object initialization.
 247                 //
 248                 public Expression CurrentInitializerVariable;
 249
 250                 DeclSpace decl_space;
 251
 252                 public DeclSpace TypeContainer;
 253                 public ILGenerator ig;
 254
 255                 [Flags]
 256                 public enum Flags : int {
 257                         /// <summary>
 258                         ///   This flag tracks the `checked' state of the compilation,
 259                         ///   it controls whether we should generate code that does overflow
 260                         ///   checking, or if we generate code that ignores overflows.
 261                         ///
 262                         ///   The default setting comes from the command line option to generate
 263                         ///   checked or unchecked code plus any source code changes using the
 264                         ///   checked/unchecked statements or expressions.   Contrast this with
 265                         ///   the ConstantCheckState flag.
 266                         /// </summary>
 267                         CheckState = 1 << 0,
 268
 269                         /// <summary>
 270                         ///   The constant check state is always set to `true' and cant be changed
 271                         ///   from the command line.  The source code can change this setting with
 272                         ///   the `checked' and `unchecked' statements and expressions.
 273                         /// </summary>
 274                         ConstantCheckState = 1 << 1,
 275
 276                         AllCheckStateFlags = CheckState | ConstantCheckState,
 277
 278                         /// <summary>
 279                         ///  Whether we are inside an unsafe block
 280                         /// </summary>
 281                         InUnsafe = 1 << 2,
 282
 283                         InCatch = 1 << 3,
 284                         InFinally = 1 << 4,
 285
 286                         /// <summary>
 287                         ///   Whether control flow analysis is enabled
 288                         /// </summary>
 289                         DoFlowAnalysis = 1 << 5,
 290
 291                         /// <summary>
 292                         ///   Whether control flow analysis is disabled on structs
 293                         ///   (only meaningful when DoFlowAnalysis is set)
 294                         /// </summary>
 295                         OmitStructFlowAnalysis = 1 << 6,
 296
 297                         ///
 298                         /// Indicates the current context is in probing mode, no errors are reported.
 299                         ///
 300                         ProbingMode = 1 <<      7,
 301
 302                         //
 303                         // Inside field intializer expression
 304                         //
 305                         InFieldInitializer = 1 << 8,
 306
 307                         InferReturnType = 1 << 9,
 308
 309                         InCompoundAssignment = 1 << 10,
 310
 311                         OmitDebuggingInfo = 1 << 11
 312                 }
 313
 314                 Flags flags;
 315
 316                 /// <summary>
 317                 ///   Whether we are emitting code inside a static or instance method
 318                 /// </summary>
 319                 public bool IsStatic;
 320
 321                 /// <summary>
 322                 ///   Whether the actual created method is static or instance method.
 323                 ///   Althoug the method might be declared as `static', if an anonymous
 324                 ///   method is involved, we might turn this into an instance method.
 325                 ///
 326                 ///   So this reflects the low-level staticness of the method, while
 327                 ///   IsStatic represents the semantic, high-level staticness.
 328                 /// </summary>
 329                 //public bool MethodIsStatic;
 330
 331                 /// <summary>
 332                 ///   The value that is allowed to be returned or NULL if there is no
 333                 ///   return type.
 334                 /// </summary>
 335                 Type return_type;
 336
 337                 /// <summary>
 338                 ///   Points to the Type (extracted from the TypeContainer) that
 339                 ///   declares this body of code
 340                 /// </summary>
 341                 public readonly Type ContainerType;
 342
 343                 /// <summary>
 344                 ///   Whether this is generating code for a constructor
 345                 /// </summary>
 346                 public bool IsConstructor;
 347
 348                 /// <summary>
 349                 ///   Keeps track of the Type to LocalBuilder temporary storage created
 350                 ///   to store structures (used to compute the address of the structure
 351                 ///   value on structure method invocations)
 352                 /// </summary>
 353                 public Hashtable temporary_storage;
 354
 355                 public Block CurrentBlock;
 356
 357                 public int CurrentFile;
 358
 359                 /// <summary>
 360                 ///   The location where we store the return value.
 361                 /// </summary>
 362                 LocalBuilder return_value;
 363
 364                 /// <summary>
 365                 ///   The location where return has to jump to return the
 366                 ///   value
 367                 /// </summary>
 368                 public Label ReturnLabel;
 369
 370                 /// <summary>
 371                 ///   If we already defined the ReturnLabel
 372                 /// </summary>
 373                 public bool HasReturnLabel;
 374
 375                 /// <summary>
 376                 ///  Whether we are in a `fixed' initialization
 377                 /// </summary>
 378                 public bool InFixedInitializer;
 379
 380                 /// <summary>
 381                 ///  Whether we are inside an anonymous method.
 382                 /// </summary>
 383                 public AnonymousExpression CurrentAnonymousMethod;
 384
 385                 /// <summary>
 386                 ///   Location for this EmitContext
 387                 /// </summary>
 388                 public Location loc;
 389
 390                 /// <summary>
 391                 ///   Inside an enum definition, we do not resolve enumeration values
 392                 ///   to their enumerations, but rather to the underlying type/value
 393                 ///   This is so EnumVal + EnumValB can be evaluated.
 394                 ///
 395                 ///   There is no "E operator + (E x, E y)", so during an enum evaluation
 396                 ///   we relax the rules
 397                 /// </summary>
 398                 public bool InEnumContext;
 399
 400                 public readonly IResolveContext ResolveContext;
 401
 402                 /// <summary>
 403                 ///    The current iterator
 404                 /// </summary>
 405                 public Iterator CurrentIterator {
 406                         get { return CurrentAnonymousMethod as Iterator; }
 407                 }
 408
 409                 /// <summary>
 410                 ///    Whether we are in the resolving stage or not
 411                 /// </summary>
 412                 enum Phase {
 413                         Created,
 414                         Resolving,
 415                         Emitting
 416                 }
 417
 418                 bool isAnonymousMethodAllowed = true;
 419
 420                 Phase current_phase;
 421                 FlowBranching current_flow_branching;
 422
 423                 static int next_id = 0;
 424                 int id = ++next_id;
 425
 426                 public override string ToString ()
 427                 {
 428                         return String.Format ("EmitContext ({0}:{1})", id,
 429                                               CurrentAnonymousMethod, loc);
 430                 }
 431
 432                 public EmitContext (IResolveContext rc, DeclSpace parent, DeclSpace ds, Location l, ILGenerator ig,
 433                                     Type return_type, int code_flags, bool is_constructor)
 434                 {
 435                         this.ResolveContext = rc;
 436                         this.ig = ig;
 437
 438                         TypeContainer = parent;
 439                         this.decl_space = ds;
 440                         if (RootContext.Checked)
 441                                 flags |= Flags.CheckState;
 442                         flags |= Flags.ConstantCheckState;
 443
 444                         if (return_type == null)
 445                                 throw new ArgumentNullException ("return_type");
 446 #if GMCS_SOURCE
 447                         if ((return_type is TypeBuilder) && return_type.IsGenericTypeDefinition)
 448                                 throw new InternalErrorException ();
 449 #endif
 450
 451                         IsStatic = (code_flags & Modifiers.STATIC) != 0;
 452                         ReturnType = return_type;
 453                         IsConstructor = is_constructor;
 454                         CurrentBlock = null;
 455                         CurrentFile = 0;
 456                         current_phase = Phase.Created;
 457
 458                         if (parent != null){
 459                                 // Can only be null for the ResolveType contexts.
 460                                 ContainerType = parent.TypeBuilder;
 461                                 if (rc.IsInUnsafeScope)
 462                                         flags |= Flags.InUnsafe;
 463                         }
 464                         loc = l;
 465                 }
 466
 467                 public EmitContext (IResolveContext rc, DeclSpace ds, Location l, ILGenerator ig,
 468                                     Type return_type, int code_flags, bool is_constructor)
 469                         : this (rc, ds, ds, l, ig, return_type, code_flags, is_constructor)
 470                 {
 471                 }
 472
 473                 public EmitContext (IResolveContext rc, DeclSpace ds, Location l, ILGenerator ig,
 474                                     Type return_type, int code_flags)
 475                         : this (rc, ds, ds, l, ig, return_type, code_flags, false)
 476                 {
 477                 }
 478
 479                 // IResolveContext.DeclContainer
 480                 public DeclSpace DeclContainer {
 481                         get { return decl_space; }
 482                         set { decl_space = value; }
 483                 }
 484
 485                 // IResolveContext.GenericDeclContainer
 486                 public DeclSpace GenericDeclContainer {
 487                         get { return DeclContainer; }
 488                 }
 489
 490                 public bool CheckState {
 491                         get { return (flags & Flags.CheckState) != 0; }
 492                 }
 493
 494                 public bool ConstantCheckState {
 495                         get { return (flags & Flags.ConstantCheckState) != 0; }
 496                 }
 497
 498                 public bool InUnsafe {
 499                         get { return (flags & Flags.InUnsafe) != 0; }
 500                 }
 501
 502                 public bool InCatch {
 503                         get { return (flags & Flags.InCatch) != 0; }
 504                 }
 505
 506                 public bool InFinally {
 507                         get { return (flags & Flags.InFinally) != 0; }
 508                 }
 509
 510                 public bool DoFlowAnalysis {
 511                         get { return (flags & Flags.DoFlowAnalysis) != 0; }
 512                 }
 513
 514                 public bool OmitStructFlowAnalysis {
 515                         get { return (flags & Flags.OmitStructFlowAnalysis) != 0; }
 516                 }
 517
 518                 // utility helper for CheckExpr, UnCheckExpr, Checked and Unchecked statements
 519                 // it's public so that we can use a struct at the callsite
 520                 public struct FlagsHandle : IDisposable
 521                 {
 522                         EmitContext ec;
 523                         readonly Flags invmask, oldval;
 524
 525                         public FlagsHandle (EmitContext ec, Flags flagsToSet)
 526                                 : this (ec, flagsToSet, flagsToSet)
 527                         {
 528                         }
 529
 530                         internal FlagsHandle (EmitContext ec, Flags mask, Flags val)
 531                         {
 532                                 this.ec = ec;
 533                                 invmask = ~mask;
 534                                 oldval = ec.flags & mask;
 535                                 ec.flags = (ec.flags & invmask) | (val & mask);
 536
 537                                 if ((mask & Flags.ProbingMode) != 0)
 538                                         Report.DisableReporting ();
 539                         }
 540
 541                         public void Dispose ()
 542                         {
 543                                 if ((invmask & Flags.ProbingMode) == 0)
 544                                         Report.EnableReporting ();
 545
 546                                 ec.flags = (ec.flags & invmask) | oldval;
 547                         }
 548                 }
 549
 550                 // Temporarily set all the given flags to the given value.  Should be used in an 'using' statement
 551                 public FlagsHandle Set (Flags flagsToSet)
 552                 {
 553                         return new FlagsHandle (this, flagsToSet);
 554                 }
 555
 556                 public FlagsHandle With (Flags bits, bool enable)
 557                 {
 558                         return new FlagsHandle (this, bits, enable ? bits : 0);
 559                 }
 560
 561                 public FlagsHandle WithFlowAnalysis (bool do_flow_analysis, bool omit_struct_analysis)
 562                 {
 563                         Flags newflags =
 564                                 (do_flow_analysis ? Flags.DoFlowAnalysis : 0) |
 565                                 (omit_struct_analysis ? Flags.OmitStructFlowAnalysis : 0);
 566                         return new FlagsHandle (this, Flags.DoFlowAnalysis | Flags.OmitStructFlowAnalysis, newflags);
 567                 }
 568
 569                 /// <summary>
 570                 ///   If this is true, then Return and ContextualReturn statements
 571                 ///   will set the ReturnType value based on the expression types
 572                 ///   of each return statement instead of the method return type
 573                 ///   (which is initially null).
 574                 /// </summary>
 575                 public bool InferReturnType {
 576                         get { return (flags & Flags.InferReturnType) != 0; }
 577                 }
 578
 579                 // IResolveContext.IsInObsoleteScope
 580                 public bool IsInObsoleteScope {
 581                         get {
 582                                 // Disables obsolete checks when probing is on
 583                                 return IsInProbingMode || ResolveContext.IsInObsoleteScope;
 584                         }
 585                 }
 586
 587                 public bool IsInProbingMode {
 588                         get { return (flags & Flags.ProbingMode) != 0; }
 589                 }
 590
 591                 // IResolveContext.IsInUnsafeScope
 592                 public bool IsInUnsafeScope {
 593                         get { return InUnsafe || ResolveContext.IsInUnsafeScope; }
 594                 }
 595
 596                 public bool IsAnonymousMethodAllowed {
 597                         get { return isAnonymousMethodAllowed; }
 598                         set { isAnonymousMethodAllowed = value; }
 599                 }
 600
 601                 public bool IsInFieldInitializer {
 602                         get { return (flags & Flags.InFieldInitializer) != 0; }
 603                 }
 604
 605                 public bool IsInCompoundAssignment {
 606                         get { return (flags & Flags.InCompoundAssignment) != 0; }
 607                 }
 608
 609                 public bool IsVariableCapturingRequired {
 610                         get {
 611                                 return !IsInProbingMode && (CurrentBranching == null || !CurrentBranching.CurrentUsageVector.IsUnreachable);
 612                         }
 613                 }
 614
 615                 public FlowBranching CurrentBranching {
 616                         get { return current_flow_branching; }
 617                 }
 618
 619                 public bool OmitDebuggingInfo {
 620                         get { return (flags & Flags.OmitDebuggingInfo) != 0; }
 621                         set {
 622                                 if (value)
 623                                         flags |= Flags.OmitDebuggingInfo;
 624                                 else
 625                                         flags &= ~Flags.OmitDebuggingInfo;
 626                         }
 627                 }
 628
 629                 // <summary>
 630                 //   Starts a new code branching.  This inherits the state of all local
 631                 //   variables and parameters from the current branching.
 632                 // </summary>
 633                 public FlowBranching StartFlowBranching (FlowBranching.BranchingType type, Location loc)
 634                 {
 635                         current_flow_branching = FlowBranching.CreateBranching (CurrentBranching, type, null, loc);
 636                         return current_flow_branching;
 637                 }
 638
 639                 // <summary>
 640                 //   Starts a new code branching for block `block'.
 641                 // </summary>
 642                 public FlowBranching StartFlowBranching (Block block)
 643                 {
 644                         flags |= Flags.DoFlowAnalysis;
 645
 646                         current_flow_branching = FlowBranching.CreateBranching (
 647                                 CurrentBranching, FlowBranching.BranchingType.Block, block, block.StartLocation);
 648                         return current_flow_branching;
 649                 }
 650
 651                 public FlowBranchingTryCatch StartFlowBranching (TryCatch stmt)
 652                 {
 653                         FlowBranchingTryCatch branching = new FlowBranchingTryCatch (CurrentBranching, stmt);
 654                         current_flow_branching = branching;
 655                         return branching;
 656                 }
 657
 658                 public FlowBranchingException StartFlowBranching (ExceptionStatement stmt)
 659                 {
 660                         FlowBranchingException branching = new FlowBranchingException (CurrentBranching, stmt);
 661                         current_flow_branching = branching;
 662                         return branching;
 663                 }
 664
 665                 public FlowBranchingLabeled StartFlowBranching (LabeledStatement stmt)
 666                 {
 667                         FlowBranchingLabeled branching = new FlowBranchingLabeled (CurrentBranching, stmt);
 668                         current_flow_branching = branching;
 669                         return branching;
 670                 }
 671
 672                 public FlowBranchingIterator StartFlowBranching (Iterator iterator)
 673                 {
 674                         FlowBranchingIterator branching = new FlowBranchingIterator (CurrentBranching, iterator);
 675                         current_flow_branching = branching;
 676                         return branching;
 677                 }
 678
 679                 public FlowBranchingToplevel StartFlowBranching (ToplevelBlock stmt)
 680                 {
 681                         FlowBranchingToplevel branching = new FlowBranchingToplevel (CurrentBranching, stmt);
 682                         current_flow_branching = branching;
 683                         return branching;
 684                 }
 685
 686                 // <summary>
 687                 //   Ends a code branching.  Merges the state of locals and parameters
 688                 //   from all the children of the ending branching.
 689                 // </summary>
 690                 public bool EndFlowBranching ()
 691                 {
 692                         FlowBranching old = current_flow_branching;
 693                         current_flow_branching = current_flow_branching.Parent;
 694
 695                         FlowBranching.UsageVector vector = current_flow_branching.MergeChild (old);
 696                         return vector.IsUnreachable;
 697                 }
 698
 699                 // <summary>
 700                 //   Kills the current code branching.  This throws away any changed state
 701                 //   information and should only be used in case of an error.
 702                 // </summary>
 703                 // FIXME: this is evil
 704                 public void KillFlowBranching ()
 705                 {
 706                         current_flow_branching = current_flow_branching.Parent;
 707                 }
 708
 709                 public bool MustCaptureVariable (LocalInfo local)
 710                 {
 711                         if (CurrentAnonymousMethod == null)
 712                                 return false;
 713
 714                         // FIXME: IsIterator is too aggressive, we should capture only if child
 715                         // block contains yield
 716                         if (CurrentAnonymousMethod.IsIterator)
 717                                 return true;
 718
 719                         return local.Block.Toplevel != CurrentBlock.Toplevel;
 720                 }
 721
 722                 public void EmitMeta (ToplevelBlock b)
 723                 {
 724                         b.EmitMeta (this);
 725
 726                         if (HasReturnLabel)
 727                                 ReturnLabel = ig.DefineLabel ();
 728                 }
 729
 730                 //
 731                 // Here until we can fix the problem with Mono.CSharp.Switch, which
 732                 // currently can not cope with ig == null during resolve (which must
 733                 // be fixed for switch statements to work on anonymous methods).
 734                 //
 735                 public void EmitTopBlock (IMethodData md, ToplevelBlock block)
 736                 {
 737                         if (block == null)
 738                                 return;
 739
 740                         bool unreachable;
 741
 742                         if (ResolveTopBlock (null, block, md.ParameterInfo, md, out unreachable)){
 743                                 if (Report.Errors > 0)
 744                                         return;
 745
 746                                 EmitMeta (block);
 747
 748                                 current_phase = Phase.Emitting;
 749 #if PRODUCTION
 750                                 try {
 751 #endif
 752                                 EmitResolvedTopBlock (block, unreachable);
 753 #if PRODUCTION
 754                                 } catch (Exception e){
 755                                         Console.WriteLine ("Exception caught by the compiler while emitting:");
 756                                         Console.WriteLine ("   Block that caused the problem begin at: " + block.loc);
 757
 758                                         Console.WriteLine (e.GetType ().FullName + ": " + e.Message);
 759                                         throw;
 760                                 }
 761 #endif
 762                         }
 763                 }
 764
 765                 bool resolved;
 766                 bool unreachable;
 767
 768                 public bool ResolveTopBlock (EmitContext anonymous_method_host, ToplevelBlock block,
 769                                              Parameters ip, IMethodData md, out bool unreachable)
 770                 {
 771                         if (resolved) {
 772                                 unreachable = this.unreachable;
 773                                 return true;
 774                         }
 775
 776                         current_phase = Phase.Resolving;
 777                         unreachable = false;
 778
 779                         if (!loc.IsNull)
 780                                 CurrentFile = loc.File;
 781
 782 #if PRODUCTION
 783                         try {
 784 #endif
 785                                 if (!block.ResolveMeta (this, ip))
 786                                         return false;
 787
 788                                 using (this.With (EmitContext.Flags.DoFlowAnalysis, true)) {
 789                                         FlowBranchingToplevel top_level;
 790                                         if (anonymous_method_host != null)
 791                                                 top_level = new FlowBranchingToplevel (anonymous_method_host.CurrentBranching, block);
 792                                         else
 793                                                 top_level = block.TopLevelBranching;
 794
 795                                         current_flow_branching = top_level;
 796                                         bool ok = block.Resolve (this);
 797                                         current_flow_branching = null;
 798
 799                                         if (!ok)
 800                                                 return false;
 801
 802                                         bool flow_unreachable = top_level.End ();
 803                                         if (flow_unreachable)
 804                                                 this.unreachable = unreachable = true;
 805                                 }
 806 #if PRODUCTION
 807                         } catch (Exception e) {
 808                                 Console.WriteLine ("Exception caught by the compiler while compiling:");
 809                                 Console.WriteLine ("   Block that caused the problem begin at: " + loc);
 810
 811                                 if (CurrentBlock != null){
 812                                         Console.WriteLine ("                     Block being compiled: [{0},{1}]",
 813                                                            CurrentBlock.StartLocation, CurrentBlock.EndLocation);
 814                                 }
 815                                 Console.WriteLine (e.GetType ().FullName + ": " + e.Message);
 816                                 throw;
 817                         }
 818 #endif
 819
 820                         if (return_type != TypeManager.void_type && !unreachable) {
 821                                 if (CurrentAnonymousMethod == null) {
 822                                         Report.Error (161, md.Location, "`{0}': not all code paths return a value", md.GetSignatureForError ());
 823                                         return false;
 824                                 } else if (!CurrentAnonymousMethod.IsIterator) {
 825                                         Report.Error (1643, CurrentAnonymousMethod.Location, "Not all code paths return a value in anonymous method of type `{0}'",
 826                                                       CurrentAnonymousMethod.GetSignatureForError ());
 827                                         return false;
 828                                 }
 829                         }
 830
 831                         resolved = true;
 832                         return true;
 833                 }
 834
 835                 public Type ReturnType {
 836                         set {
 837                                 return_type = value;
 838                         }
 839                         get {
 840                                 return return_type;
 841                         }
 842                 }
 843
 844                 public void EmitResolvedTopBlock (ToplevelBlock block, bool unreachable)
 845                 {
 846                         if (block != null)
 847                                 block.Emit (this);
 848
 849                         if (HasReturnLabel)
 850                                 ig.MarkLabel (ReturnLabel);
 851
 852                         if (return_value != null){
 853                                 ig.Emit (OpCodes.Ldloc, return_value);
 854                                 ig.Emit (OpCodes.Ret);
 855                         } else {
 856                                 //
 857                                 // If `HasReturnLabel' is set, then we already emitted a
 858                                 // jump to the end of the method, so we must emit a `ret'
 859                                 // there.
 860                                 //
 861                                 // Unfortunately, System.Reflection.Emit automatically emits
 862                                 // a leave to the end of a finally block.  This is a problem
 863                                 // if no code is following the try/finally block since we may
 864                                 // jump to a point after the end of the method.
 865                                 // As a workaround, we're always creating a return label in
 866                                 // this case.
 867                                 //
 868
 869                                 if ((block != null) && block.IsDestructor) {
 870                                         // Nothing to do; S.R.E automatically emits a leave.
 871                                 } else if (HasReturnLabel || !unreachable) {
 872                                         if (return_type != TypeManager.void_type)
 873                                                 ig.Emit (OpCodes.Ldloc, TemporaryReturn ());
 874                                         ig.Emit (OpCodes.Ret);
 875                                 }
 876                         }
 877                 }
 878
 879                 /// <summary>
 880                 ///   This is called immediately before emitting an IL opcode to tell the symbol
 881                 ///   writer to which source line this opcode belongs.
 882                 /// </summary>
 883                 public void Mark (Location loc)
 884                 {
 885                         if (!SymbolWriter.HasSymbolWriter || OmitDebuggingInfo || loc.IsNull)
 886                                 return;
 887
 888                         SymbolWriter.MarkSequencePoint (ig, loc);
 889                 }
 890
 891                 public void DefineLocalVariable (string name, LocalBuilder builder)
 892                 {
 893                         SymbolWriter.DefineLocalVariable (name, builder);
 894                 }
 895
 896                 public void BeginScope ()
 897                 {
 898                         ig.BeginScope();
 899                         SymbolWriter.OpenScope(ig);
 900                 }
 901
 902                 public void EndScope ()
 903                 {
 904                         ig.EndScope();
 905                         SymbolWriter.CloseScope(ig);
 906                 }
 907
 908                 /// <summary>
 909                 ///   Returns a temporary storage for a variable of type t as
 910                 ///   a local variable in the current body.
 911                 /// </summary>
 912                 public LocalBuilder GetTemporaryLocal (Type t)
 913                 {
 914                         if (temporary_storage != null) {
 915                                 object o = temporary_storage [t];
 916                                 if (o != null) {
 917                                         if (o is Stack) {
 918                                                 Stack s = (Stack) o;
 919                                                 o = s.Count == 0 ? null : s.Pop ();
 920                                         } else {
 921                                                 temporary_storage.Remove (t);
 922                                         }
 923                                 }
 924                                 if (o != null)
 925                                         return (LocalBuilder) o;
 926                         }
 927                         return ig.DeclareLocal (t);
 928                 }
 929
 930                 public void FreeTemporaryLocal (LocalBuilder b, Type t)
 931                 {
 932                         if (temporary_storage == null) {
 933                                 temporary_storage = new Hashtable ();
 934                                 temporary_storage [t] = b;
 935                                 return;
 936                         }
 937                         object o = temporary_storage [t];
 938                         if (o == null) {
 939                                 temporary_storage [t] = b;
 940                                 return;
 941                         }
 942                         Stack s = o as Stack;
 943                         if (s == null) {
 944                                 s = new Stack ();
 945                                 s.Push (o);
 946                                 temporary_storage [t] = s;
 947                         }
 948                         s.Push (b);
 949                 }
 950
 951                 /// <summary>
 952                 ///   Current loop begin and end labels.
 953                 /// </summary>
 954                 public Label LoopBegin, LoopEnd;
 955
 956                 /// <summary>
 957                 ///   Default target in a switch statement.   Only valid if
 958                 ///   InSwitch is true
 959                 /// </summary>
 960                 public Label DefaultTarget;
 961
 962                 /// <summary>
 963                 ///   If this is non-null, points to the current switch statement
 964                 /// </summary>
 965                 public Switch Switch;
 966
 967                 /// <summary>
 968                 ///   ReturnValue creates on demand the LocalBuilder for the
 969                 ///   return value from the function.  By default this is not
 970                 ///   used.  This is only required when returns are found inside
 971                 ///   Try or Catch statements.
 972                 ///
 973                 ///   This method is typically invoked from the Emit phase, so
 974                 ///   we allow the creation of a return label if it was not
 975                 ///   requested during the resolution phase.   Could be cleaned
 976                 ///   up, but it would replicate a lot of logic in the Emit phase
 977                 ///   of the code that uses it.
 978                 /// </summary>
 979                 public LocalBuilder TemporaryReturn ()
 980                 {
 981                         if (return_value == null){
 982                                 return_value = ig.DeclareLocal (return_type);
 983                                 if (!HasReturnLabel){
 984                                         ReturnLabel = ig.DefineLabel ();
 985                                         HasReturnLabel = true;
 986                                 }
 987                         }
 988
 989                         return return_value;
 990                 }
 991
 992                 /// <summary>
 993                 ///   This method is used during the Resolution phase to flag the
 994                 ///   need to define the ReturnLabel
 995                 /// </summary>
 996                 public void NeedReturnLabel ()
 997                 {
 998                         if (current_phase != Phase.Resolving){
 999                                 //
1000                                 // The reason is that the `ReturnLabel' is declared between
1001                                 // resolution and emission
1002                                 //
1003                                 throw new Exception ("NeedReturnLabel called from Emit phase, should only be called during Resolve");
1004                         }
1005
1006                         if (!HasReturnLabel)
1007                                 HasReturnLabel = true;
1008                 }
1009
1010
1011                 public Expression GetThis (Location loc)
1012                 {
1013                         This my_this;
1014                         if (CurrentBlock != null)
1015                                 my_this = new This (CurrentBlock, loc);
1016                         else
1017                                 my_this = new This (loc);
1018
1019                         if (!my_this.ResolveBase (this))
1020                                 my_this = null;
1021
1022                         return my_this;
1023                 }
1024         }
1025
1026
1027         public abstract class CommonAssemblyModulClass : Attributable, IResolveContext {
1028
1029                 protected CommonAssemblyModulClass ():
1030                         base (null)
1031                 {
1032                 }
1033
1034                 public void AddAttributes (ArrayList attrs)
1035                 {
1036                         foreach (Attribute a in attrs)
1037                                 a.AttachTo (this);
1038
1039                         if (attributes == null) {
1040                                 attributes = new Attributes (attrs);
1041                                 return;
1042                         }
1043                         attributes.AddAttributes (attrs);
1044                 }
1045
1046                 public virtual void Emit (TypeContainer tc)
1047                 {
1048                         if (OptAttributes == null)
1049                                 return;
1050
1051                         OptAttributes.Emit ();
1052                 }
1053
1054                 protected Attribute ResolveAttribute (Type a_type)
1055                 {
1056                         Attribute a = OptAttributes.Search (a_type);
1057                         if (a != null) {
1058                                 a.Resolve ();
1059                         }
1060                         return a;
1061                 }
1062
1063                 public override IResolveContext ResolveContext {
1064                         get { return this; }
1065                 }
1066
1067                 #region IResolveContext Members
1068
1069                 public DeclSpace DeclContainer {
1070                         get { return RootContext.ToplevelTypes; }
1071                 }
1072
1073                 public DeclSpace GenericDeclContainer {
1074                         get { return DeclContainer; }
1075                 }
1076
1077                 public bool IsInObsoleteScope {
1078                         get { return false; }
1079                 }
1080
1081                 public bool IsInUnsafeScope {
1082                         get { return false; }
1083                 }
1084
1085                 #endregion
1086         }
1087
1088         public class AssemblyClass : CommonAssemblyModulClass {
1089                 // TODO: make it private and move all builder based methods here
1090                 public AssemblyBuilder Builder;
1091                 bool is_cls_compliant;
1092                 bool wrap_non_exception_throws;
1093                 Type runtime_compatibility_attr_type;
1094
1095                 public Attribute ClsCompliantAttribute;
1096
1097                 ListDictionary declarative_security;
1098 #if GMCS_SOURCE
1099                 bool has_extension_method;
1100                 public AssemblyName Name;
1101                 MethodInfo add_type_forwarder;
1102                 ListDictionary emitted_forwarders;
1103 #endif
1104
1105                 // Module is here just because of error messages
1106                 static string[] attribute_targets = new string [] { "assembly", "module" };
1107
1108                 public AssemblyClass (): base ()
1109                 {
1110 #if GMCS_SOURCE
1111                         wrap_non_exception_throws = true;
1112 #endif
1113                 }
1114
1115                 public bool HasExtensionMethods {
1116                         set {
1117 #if GMCS_SOURCE
1118                                 has_extension_method = value;
1119 #endif
1120                         }
1121                 }
1122
1123                 public bool IsClsCompliant {
1124                         get {
1125                                 return is_cls_compliant;
1126                         }
1127                 }
1128
1129                 public bool WrapNonExceptionThrows {
1130                         get {
1131                                 return wrap_non_exception_throws;
1132                         }
1133                 }
1134
1135                 public override AttributeTargets AttributeTargets {
1136                         get {
1137                                 return AttributeTargets.Assembly;
1138                         }
1139                 }
1140
1141                 public override bool IsClsComplianceRequired ()
1142                 {
1143                         return is_cls_compliant;
1144                 }
1145
1146                 public void Resolve ()
1147                 {
1148                         runtime_compatibility_attr_type = TypeManager.CoreLookupType (
1149                                 "System.Runtime.CompilerServices", "RuntimeCompatibilityAttribute", Kind.Class, false);
1150
1151                         if (OptAttributes == null)
1152                                 return;
1153
1154                         // Ensure that we only have GlobalAttributes, since the Search isn't safe with other types.
1155                         if (!OptAttributes.CheckTargets())
1156                                 return;
1157
1158                         if (TypeManager.cls_compliant_attribute_type != null)
1159                                 ClsCompliantAttribute = ResolveAttribute (TypeManager.cls_compliant_attribute_type);
1160
1161                         if (ClsCompliantAttribute != null) {
1162                                 is_cls_compliant = ClsCompliantAttribute.GetClsCompliantAttributeValue ();
1163                         }
1164
1165                         if (runtime_compatibility_attr_type != null) {
1166                                 Attribute a = ResolveAttribute (runtime_compatibility_attr_type);
1167                                 if (a != null) {
1168                                         object val = a.GetPropertyValue ("WrapNonExceptionThrows");
1169                                         if (val != null)
1170                                                 wrap_non_exception_throws = (bool) val;
1171                                 }
1172                         }
1173                 }
1174
1175                 // fix bug #56621
1176                 private void SetPublicKey (AssemblyName an, byte[] strongNameBlob)
1177                 {
1178                         try {
1179                                 // check for possible ECMA key
1180                                 if (strongNameBlob.Length == 16) {
1181                                         // will be rejected if not "the" ECMA key
1182                                         an.SetPublicKey (strongNameBlob);
1183                                 }
1184                                 else {
1185                                         // take it, with or without, a private key
1186                                         RSA rsa = CryptoConvert.FromCapiKeyBlob (strongNameBlob);
1187                                         // and make sure we only feed the public part to Sys.Ref
1188                                         byte[] publickey = CryptoConvert.ToCapiPublicKeyBlob (rsa);
1189
1190                                         // AssemblyName.SetPublicKey requires an additional header
1191                                         byte[] publicKeyHeader = new byte [12] { 0x00, 0x24, 0x00, 0x00, 0x04, 0x80, 0x00, 0x00, 0x94, 0x00, 0x00, 0x00 };
1192
1193                                         byte[] encodedPublicKey = new byte [12 + publickey.Length];
1194                                         Buffer.BlockCopy (publicKeyHeader, 0, encodedPublicKey, 0, 12);
1195                                         Buffer.BlockCopy (publickey, 0, encodedPublicKey, 12, publickey.Length);
1196                                         an.SetPublicKey (encodedPublicKey);
1197                                 }
1198                         }
1199                         catch (Exception) {
1200                                 Error_AssemblySigning ("The specified file `" + RootContext.StrongNameKeyFile + "' is incorrectly encoded");
1201                                 Environment.Exit (1);
1202                         }
1203                 }
1204
1205                 // TODO: rewrite this code (to kill N bugs and make it faster) and use standard ApplyAttribute way.
1206                 public AssemblyName GetAssemblyName (string name, string output)
1207                 {
1208                         if (OptAttributes != null) {
1209                                 foreach (Attribute a in OptAttributes.Attrs) {
1210                                         // cannot rely on any resolve-based members before you call Resolve
1211                                         if (a.ExplicitTarget == null || a.ExplicitTarget != "assembly")
1212                                                 continue;
1213
1214                                         // TODO: This code is buggy: comparing Attribute name without resolving is wrong.
1215                                         //       However, this is invoked by CodeGen.Init, when none of the namespaces
1216                                         //       are loaded yet.
1217                                         // TODO: Does not handle quoted attributes properly
1218                                         switch (a.Name) {
1219                                         case "AssemblyKeyFile":
1220                                         case "AssemblyKeyFileAttribute":
1221                                         case "System.Reflection.AssemblyKeyFileAttribute":
1222                                                 if (RootContext.StrongNameKeyFile != null) {
1223                                                         Report.SymbolRelatedToPreviousError (a.Location, a.Name);
1224                                                         Report.Warning (1616, 1, "Option `{0}' overrides attribute `{1}' given in a source file or added module",
1225                                                                         "keyfile", "System.Reflection.AssemblyKeyFileAttribute");
1226                                                 } else {
1227                                                         string value = a.GetString ();
1228                                                         if (value.Length != 0)
1229                                                                 RootContext.StrongNameKeyFile = value;
1230                                                 }
1231                                                 break;
1232                                         case "AssemblyKeyName":
1233                                         case "AssemblyKeyNameAttribute":
1234                                         case "System.Reflection.AssemblyKeyNameAttribute":
1235                                                 if (RootContext.StrongNameKeyContainer != null) {
1236                                                         Report.SymbolRelatedToPreviousError (a.Location, a.Name);
1237                                                         Report.Warning (1616, 1, "Option `{0}' overrides attribute `{1}' given in a source file or added module",
1238                                                                         "keycontainer", "System.Reflection.AssemblyKeyNameAttribute");
1239                                                 } else {
1240                                                         string value = a.GetString ();
1241                                                         if (value.Length != 0)
1242                                                                 RootContext.StrongNameKeyContainer = value;
1243                                                 }
1244                                                 break;
1245                                         case "AssemblyDelaySign":
1246                                         case "AssemblyDelaySignAttribute":
1247                                         case "System.Reflection.AssemblyDelaySignAttribute":
1248                                                 RootContext.StrongNameDelaySign = a.GetBoolean ();
1249                                                 break;
1250                                         }
1251                                 }
1252                         }
1253
1254                         AssemblyName an = new AssemblyName ();
1255                         an.Name = Path.GetFileNameWithoutExtension (name);
1256
1257                         // note: delay doesn't apply when using a key container
1258                         if (RootContext.StrongNameKeyContainer != null) {
1259                                 an.KeyPair = new StrongNameKeyPair (RootContext.StrongNameKeyContainer);
1260                                 return an;
1261                         }
1262
1263                         // strongname is optional
1264                         if (RootContext.StrongNameKeyFile == null)
1265                                 return an;
1266
1267                         string AssemblyDir = Path.GetDirectoryName (output);
1268
1269                         // the StrongName key file may be relative to (a) the compiled
1270                         // file or (b) to the output assembly. See bugzilla #55320
1271                         // http://bugzilla.ximian.com/show_bug.cgi?id=55320
1272
1273                         // (a) relative to the compiled file
1274                         string filename = Path.GetFullPath (RootContext.StrongNameKeyFile);
1275                         bool exist = File.Exists (filename);
1276                         if ((!exist) && (AssemblyDir != null) && (AssemblyDir != String.Empty)) {
1277                                 // (b) relative to the outputed assembly
1278                                 filename = Path.GetFullPath (Path.Combine (AssemblyDir, RootContext.StrongNameKeyFile));
1279                                 exist = File.Exists (filename);
1280                         }
1281
1282                         if (exist) {
1283                                 using (FileStream fs = new FileStream (filename, FileMode.Open, FileAccess.Read)) {
1284                                         byte[] snkeypair = new byte [fs.Length];
1285                                         fs.Read (snkeypair, 0, snkeypair.Length);
1286
1287                                         if (RootContext.StrongNameDelaySign) {
1288                                                 // delayed signing - DO NOT include private key
1289                                                 SetPublicKey (an, snkeypair);
1290                                         }
1291                                         else {
1292                                                 // no delay so we make sure we have the private key
1293                                                 try {
1294                                                         CryptoConvert.FromCapiPrivateKeyBlob (snkeypair);
1295                                                         an.KeyPair = new StrongNameKeyPair (snkeypair);
1296                                                 }
1297                                                 catch (CryptographicException) {
1298                                                         if (snkeypair.Length == 16) {
1299                                                                 // error # is different for ECMA key
1300                                                                 Report.Error (1606, "Could not sign the assembly. " +
1301                                                                         "ECMA key can only be used to delay-sign assemblies");
1302                                                         }
1303                                                         else {
1304                                                                 Error_AssemblySigning ("The specified file `" + RootContext.StrongNameKeyFile + "' does not have a private key");
1305                                                         }
1306                                                         return null;
1307                                                 }
1308                                         }
1309                                 }
1310                         }
1311                         else {
1312                                 Error_AssemblySigning ("The specified file `" + RootContext.StrongNameKeyFile + "' does not exist");
1313                                 return null;
1314                         }
1315                         return an;
1316                 }
1317
1318                 void Error_AssemblySigning (string text)
1319                 {
1320                         Report.Error (1548, "Error during assembly signing. " + text);
1321                 }
1322
1323 #if GMCS_SOURCE
1324                 bool CheckInternalsVisibleAttribute (Attribute a)
1325                 {
1326                         string assembly_name = a.GetString ();
1327                         if (assembly_name.Length == 0)
1328                                 return false;
1329
1330                         AssemblyName aname = null;
1331                         try {
1332                                 aname = new AssemblyName (assembly_name);
1333                         } catch (FileLoadException) {
1334                         } catch (ArgumentException) {
1335                         }
1336
1337                         // Bad assembly name format
1338                         if (aname == null)
1339                                 Report.Warning (1700, 3, a.Location, "Assembly reference `" + assembly_name + "' is invalid and cannot be resolved");
1340                         // Report error if we have defined Version or Culture
1341                         else if (aname.Version != null || aname.CultureInfo != null)
1342                                 throw new Exception ("Friend assembly `" + a.GetString () +
1343                                                 "' is invalid. InternalsVisibleTo cannot have version or culture specified.");
1344                         else if (aname.GetPublicKey () == null && Name.GetPublicKey () != null && Name.GetPublicKey ().Length != 0) {
1345                                 Report.Error (1726, a.Location, "Friend assembly reference `" + aname.FullName + "' is invalid." +
1346                                                 " Strong named assemblies must specify a public key in their InternalsVisibleTo declarations");
1347                                 return false;
1348                         }
1349
1350                         return true;
1351                 }
1352 #endif
1353
1354                 static bool IsValidAssemblyVersion (string version)
1355                 {
1356                         Version v;
1357                         try {
1358                                 v = new Version (version);
1359                         } catch {
1360                                 try {
1361                                         int major = int.Parse (version, CultureInfo.InvariantCulture);
1362                                         v = new Version (major, 0);
1363                                 } catch {
1364                                         return false;
1365                                 }
1366                         }
1367
1368                         foreach (int candidate in new int [] { v.Major, v.Minor, v.Build, v.Revision }) {
1369                                 if (candidate > ushort.MaxValue)
1370                                         return false;
1371                         }
1372
1373                         return true;
1374                 }
1375
1376                 public override void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder customBuilder)
1377                 {
1378                         if (a.IsValidSecurityAttribute ()) {
1379                                 if (declarative_security == null)
1380                                         declarative_security = new ListDictionary ();
1381
1382                                 a.ExtractSecurityPermissionSet (declarative_security);
1383                                 return;
1384                         }
1385
1386                         if (a.Type == TypeManager.assembly_culture_attribute_type) {
1387                                 string value = a.GetString ();
1388                                 if (value == null || value.Length == 0)
1389                                         return;
1390
1391                                 if (RootContext.Target == Target.Exe) {
1392                                         a.Error_AttributeEmitError ("The executables cannot be satelite assemblies, remove the attribute or keep it empty");
1393                                         return;
1394                                 }
1395                         }
1396
1397                         if (a.Type == TypeManager.assembly_version_attribute_type) {
1398                                 string value = a.GetString ();
1399                                 if (value == null || value.Length == 0)
1400                                         return;
1401
1402                                 value = value.Replace ('*', '0');
1403
1404                                 if (!IsValidAssemblyVersion (value)) {
1405                                         a.Error_AttributeEmitError (string.Format ("Specified version `{0}' is not valid", value));
1406                                         return;
1407                                 }
1408                         }
1409
1410 #if GMCS_SOURCE
1411                         if (a.Type == TypeManager.internals_visible_attr_type && !CheckInternalsVisibleAttribute (a))
1412                                 return;
1413
1414                         if (a.Type == TypeManager.type_forwarder_attr_type) {
1415                                 Type t = a.GetArgumentType ();
1416                                 if (t == null || TypeManager.HasElementType (t)) {
1417                                         Report.Error (735, a.Location, "Invalid type specified as an argument for TypeForwardedTo attribute");
1418                                         return;
1419                                 }
1420
1421                                 if (emitted_forwarders == null) {
1422                                         emitted_forwarders = new ListDictionary();
1423                                 } else if (emitted_forwarders.Contains(t)) {
1424                                         Report.SymbolRelatedToPreviousError(((Attribute)emitted_forwarders[t]).Location, null);
1425                                         Report.Error(739, a.Location, "A duplicate type forward of type `{0}'",
1426                                                 TypeManager.CSharpName(t));
1427                                         return;
1428                                 }
1429
1430                                 emitted_forwarders.Add(t, a);
1431
1432                                 if (TypeManager.LookupDeclSpace (t) != null) {
1433                                         Report.SymbolRelatedToPreviousError (t);
1434                                         Report.Error (729, a.Location, "Cannot forward type `{0}' because it is defined in this assembly",
1435                                                 TypeManager.CSharpName (t));
1436                                         return;
1437                                 }
1438
1439                                 if (t.IsNested) {
1440                                         Report.Error (730, a.Location, "Cannot forward type `{0}' because it is a nested type",
1441                                                 TypeManager.CSharpName (t));
1442                                         return;
1443                                 }
1444
1445                                 if (t.IsGenericType) {
1446                                         Report.Error (733, a.Location, "Cannot forward generic type `{0}'", TypeManager.CSharpName (t));
1447                                         return;
1448                                 }
1449
1450                                 if (add_type_forwarder == null) {
1451                                         add_type_forwarder = typeof (AssemblyBuilder).GetMethod ("AddTypeForwarder",
1452                                                 BindingFlags.NonPublic | BindingFlags.Instance);
1453
1454                                         if (add_type_forwarder == null) {
1455                                                 Report.RuntimeMissingSupport (a.Location, "TypeForwardedTo attribute");
1456                                                 return;
1457                                         }
1458                                 }
1459
1460                                 add_type_forwarder.Invoke (Builder, new object[] { t });
1461                                 return;
1462                         }
1463
1464                         if (a.Type == TypeManager.extension_attribute_type) {
1465                                 a.Error_MisusedExtensionAttribute ();
1466                                 return;
1467                         }
1468 #endif
1469                         Builder.SetCustomAttribute (customBuilder);
1470                 }
1471
1472                 public override void Emit (TypeContainer tc)
1473                 {
1474                         base.Emit (tc);
1475
1476 #if GMCS_SOURCE
1477                         if (has_extension_method)
1478                                 Builder.SetCustomAttribute (TypeManager.extension_attribute_attr);
1479 #endif
1480
1481                         if (runtime_compatibility_attr_type != null) {
1482                                 // FIXME: Does this belong inside SRE.AssemblyBuilder instead?
1483                                 if (OptAttributes == null || !OptAttributes.Contains (runtime_compatibility_attr_type)) {
1484                                         ConstructorInfo ci = TypeManager.GetPredefinedConstructor (
1485                                                 runtime_compatibility_attr_type, Location.Null, Type.EmptyTypes);
1486                                         PropertyInfo [] pis = new PropertyInfo [1];
1487                                         pis [0] = TypeManager.GetPredefinedProperty (runtime_compatibility_attr_type,
1488                                                 "WrapNonExceptionThrows", Location.Null, TypeManager.bool_type);
1489                                         object [] pargs = new object [1];
1490                                         pargs [0] = true;
1491                                         Builder.SetCustomAttribute (new CustomAttributeBuilder (ci, new object [0], pis, pargs));
1492                                 }
1493                         }
1494
1495                         if (declarative_security != null) {
1496
1497                                 MethodInfo add_permission = typeof (AssemblyBuilder).GetMethod ("AddPermissionRequests", BindingFlags.Instance | BindingFlags.NonPublic);
1498                                 object builder_instance = Builder;
1499
1500                                 try {
1501                                         // Microsoft runtime hacking
1502                                         if (add_permission == null) {
1503                                                 Type assembly_builder = typeof (AssemblyBuilder).Assembly.GetType ("System.Reflection.Emit.AssemblyBuilderData");
1504                                                 add_permission = assembly_builder.GetMethod ("AddPermissionRequests", BindingFlags.Instance | BindingFlags.NonPublic);
1505
1506                                                 FieldInfo fi = typeof (AssemblyBuilder).GetField ("m_assemblyData", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.GetField);
1507                                                 builder_instance = fi.GetValue (Builder);
1508                                         }
1509
1510                                         object[] args = new object [] { declarative_security [SecurityAction.RequestMinimum],
1511                                                                                                   declarative_security [SecurityAction.RequestOptional],
1512                                                                                                   declarative_security [SecurityAction.RequestRefuse] };
1513                                         add_permission.Invoke (builder_instance, args);
1514                                 }
1515                                 catch {
1516                                         Report.RuntimeMissingSupport (Location.Null, "assembly permission setting");
1517                                 }
1518                         }
1519                 }
1520
1521                 public override string[] ValidAttributeTargets {
1522                         get {
1523                                 return attribute_targets;
1524                         }
1525                 }
1526
1527                 // Wrapper for AssemblyBuilder.AddModule
1528                 static MethodInfo adder_method;
1529                 static public MethodInfo AddModule_Method {
1530                         get {
1531                                 if (adder_method == null)
1532                                         adder_method = typeof (AssemblyBuilder).GetMethod ("AddModule", BindingFlags.Instance|BindingFlags.NonPublic);
1533                                 return adder_method;
1534                         }
1535                 }
1536                 public Module AddModule (string module)
1537                 {
1538                         MethodInfo m = AddModule_Method;
1539                         if (m == null) {
1540                                 Report.RuntimeMissingSupport (Location.Null, "/addmodule");
1541                                 Environment.Exit (1);
1542                         }
1543
1544                         try {
1545                                 return (Module) m.Invoke (Builder, new object [] { module });
1546                         } catch (TargetInvocationException ex) {
1547                                 throw ex.InnerException;
1548                         }
1549                 }
1550         }
1551
1552         public class ModuleClass : CommonAssemblyModulClass {
1553                 // TODO: make it private and move all builder based methods here
1554                 public ModuleBuilder Builder;
1555                 bool m_module_is_unsafe;
1556 #if GMCS_SOURCE
1557                 bool has_default_charset;
1558 #endif
1559
1560                 public CharSet DefaultCharSet = CharSet.Ansi;
1561                 public TypeAttributes DefaultCharSetType = TypeAttributes.AnsiClass;
1562
1563                 static string[] attribute_targets = new string [] { "module" };
1564
1565                 public ModuleClass (bool is_unsafe)
1566                 {
1567                         m_module_is_unsafe = is_unsafe;
1568                 }
1569
1570                 public override AttributeTargets AttributeTargets {
1571                         get {
1572                                 return AttributeTargets.Module;
1573                         }
1574                 }
1575
1576                 public override bool IsClsComplianceRequired ()
1577                 {
1578                         return CodeGen.Assembly.IsClsCompliant;
1579                 }
1580
1581                 public override void Emit (TypeContainer tc)
1582                 {
1583                         base.Emit (tc);
1584
1585                         if (m_module_is_unsafe) {
1586                                 Type t = TypeManager.CoreLookupType ("System.Security", "UnverifiableCodeAttribute", Kind.Class, true);
1587                                 if (t != null) {
1588                                         ConstructorInfo unverifiable_code_ctor = TypeManager.GetPredefinedConstructor (t, Location.Null, Type.EmptyTypes);
1589                                         if (unverifiable_code_ctor != null)
1590                                                 Builder.SetCustomAttribute (new CustomAttributeBuilder (unverifiable_code_ctor, new object [0]));
1591                                 }
1592                         }
1593                 }
1594
1595                 public override void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder customBuilder)
1596                 {
1597                         if (a.Type == TypeManager.cls_compliant_attribute_type) {
1598                                 if (CodeGen.Assembly.ClsCompliantAttribute == null) {
1599                                         Report.Warning (3012, 1, a.Location, "You must specify the CLSCompliant attribute on the assembly, not the module, to enable CLS compliance checking");
1600                                 }
1601                                 else if (CodeGen.Assembly.IsClsCompliant != a.GetBoolean ()) {
1602                                         Report.SymbolRelatedToPreviousError (CodeGen.Assembly.ClsCompliantAttribute.Location, CodeGen.Assembly.ClsCompliantAttribute.GetSignatureForError ());
1603                                         Report.Warning (3017, 1, a.Location, "You cannot specify the CLSCompliant attribute on a module that differs from the CLSCompliant attribute on the assembly");
1604                                         return;
1605                                 }
1606                         }
1607
1608                         Builder.SetCustomAttribute (customBuilder);
1609                 }
1610
1611                 public bool HasDefaultCharSet {
1612                         get {
1613 #if GMCS_SOURCE
1614                                 return has_default_charset;
1615 #else
1616                                 return false;
1617 #endif
1618                         }
1619                 }
1620
1621                 /// <summary>
1622                 /// It is called very early therefore can resolve only predefined attributes
1623                 /// </summary>
1624                 public void Resolve ()
1625                 {
1626 #if GMCS_SOURCE
1627                         if (OptAttributes == null)
1628                                 return;
1629
1630                         if (!OptAttributes.CheckTargets())
1631                                 return;
1632
1633                         if (TypeManager.default_charset_type == null)
1634                                 return;
1635
1636                         Attribute a = ResolveAttribute (TypeManager.default_charset_type);
1637                         if (a != null) {
1638                                 has_default_charset = true;
1639                                 DefaultCharSet = a.GetCharSetValue ();
1640                                 switch (DefaultCharSet) {
1641                                 case CharSet.Ansi:
1642                                 case CharSet.None:
1643                                         break;
1644                                 case CharSet.Auto:
1645                                         DefaultCharSetType = TypeAttributes.AutoClass;
1646                                         break;
1647                                 case CharSet.Unicode:
1648                                         DefaultCharSetType = TypeAttributes.UnicodeClass;
1649                                         break;
1650                                 default:
1651                                         Report.Error (1724, a.Location, "Value specified for the argument to 'System.Runtime.InteropServices.DefaultCharSetAttribute' is not valid");
1652                                         break;
1653                                 }
1654                         }
1655 #endif
1656                 }
1657
1658                 public override string[] ValidAttributeTargets {
1659                         get {
1660                                 return attribute_targets;
1661                         }
1662                 }
1663         }
1664 }