mcs/mcs/membercache.cs

   1 //
   2 // membercache.cs: A container for all member lookups
   3 //
   4 // Author: Miguel de Icaza (miguel@gnu.org)
   5 //         Marek Safar (marek.safar@gmail.com)
   6 //
   7 // Dual licensed under the terms of the MIT X11 or GNU GPL
   8 //
   9 // Copyright 2001 Ximian, Inc (http://www.ximian.com)
  10 // Copyright 2004-2010 Novell, Inc
  11 // Copyright 2011 Xamarin Inc
  12 //
  13 //
  14
  15 using System;
  16 using System.Collections.Generic;
  17
  18 namespace Mono.CSharp {
  19
  20         [Flags]
  21         public enum MemberKind
  22         {
  23                 Constructor = 1,
  24                 Event = 1 << 1,
  25                 Field = 1 << 2,
  26                 Method = 1 << 3,
  27                 Property = 1 << 4,
  28                 Indexer = 1 << 5,
  29                 Operator = 1 << 6,
  30                 Destructor      = 1 << 7,
  31
  32                 Class           = 1 << 11,
  33                 Struct          = 1 << 12,
  34                 Delegate        = 1 << 13,
  35                 Enum            = 1 << 14,
  36                 Interface       = 1 << 15,
  37                 TypeParameter = 1 << 16,
  38
  39                 ArrayType = 1 << 19,
  40                 PointerType = 1 << 20,
  41                 InternalCompilerType = 1 << 21,
  42                 MissingType = 1 << 22,
  43                 Void = 1 << 23,
  44                 Namespace = 1 << 24,
  45
  46                 NestedMask = Class | Struct | Delegate | Enum | Interface,
  47                 GenericMask = Method | Class | Struct | Delegate | Interface,
  48                 MaskType = Constructor | Event | Field | Method | Property | Indexer | Operator | Destructor | NestedMask
  49         }
  50
  51         [Flags]
  52         public enum BindingRestriction
  53         {
  54                 None = 0,
  55
  56                 // Inspect only queried type members
  57                 DeclaredOnly = 1 << 1,
  58
  59                 // Exclude static
  60                 InstanceOnly = 1 << 2,
  61
  62                 NoAccessors = 1 << 3,
  63
  64                 // Member has to be override
  65                 OverrideOnly = 1 << 4
  66         }
  67
  68         public struct MemberFilter : IEquatable<MemberSpec>
  69         {
  70                 public readonly string Name;
  71                 public readonly MemberKind Kind;
  72                 public readonly AParametersCollection Parameters;
  73                 public readonly TypeSpec MemberType;
  74                 public readonly int Arity; // -1 to ignore the check
  75
  76                 public MemberFilter (MethodSpec m)
  77                 {
  78                         Name = m.Name;
  79                         Kind = MemberKind.Method;
  80                         Parameters = m.Parameters;
  81                         MemberType = m.ReturnType;
  82                         Arity = m.Arity;
  83                 }
  84
  85                 public MemberFilter (string name, int arity, MemberKind kind, AParametersCollection param, TypeSpec type)
  86                 {
  87                         Name = name;
  88                         Kind = kind;
  89                         Parameters = param;
  90                         MemberType = type;
  91                         this.Arity = arity;
  92                 }
  93
  94                 public static MemberFilter Constructor (AParametersCollection param)
  95                 {
  96                         return new MemberFilter (Mono.CSharp.Constructor.ConstructorName, 0, MemberKind.Constructor, param, null);
  97                 }
  98
  99                 public static MemberFilter Property (string name, TypeSpec type)
 100                 {
 101                         return new MemberFilter (name, 0, MemberKind.Property, null, type);
 102                 }
 103
 104                 public static MemberFilter Field (string name, TypeSpec type)
 105                 {
 106                         return new MemberFilter (name, 0, MemberKind.Field, null, type);
 107                 }
 108
 109                 public static MemberFilter Method (string name, int arity, AParametersCollection param, TypeSpec type)
 110                 {
 111                         return new MemberFilter (name, arity, MemberKind.Method, param, type);
 112                 }
 113
 114                 #region IEquatable<MemberSpec> Members
 115
 116                 public bool Equals (MemberSpec other)
 117                 {
 118                         // Is the member of the correct type ?
 119                         // TODO: Isn't this redundant ?
 120                         if ((other.Kind & Kind & MemberKind.MaskType) == 0)
 121                                 return false;
 122
 123                         // Check arity when not disabled
 124                         if (Arity >= 0 && Arity != other.Arity)
 125                                 return false;
 126
 127                         if (Parameters != null) {
 128                                 if (other is IParametersMember) {
 129                                         var other_param = ((IParametersMember) other).Parameters;
 130                                         if (!TypeSpecComparer.Override.IsEqual (Parameters, other_param))
 131                                                 return false;
 132                                 } else {
 133                                         return false;
 134                                 }
 135                         }
 136
 137                         if (MemberType != null) {
 138                                 if (other is IInterfaceMemberSpec) {
 139                                         var other_type = ((IInterfaceMemberSpec) other).MemberType;
 140                                         if (!TypeSpecComparer.Override.IsEqual (other_type, MemberType))
 141                                                 return false;
 142                                 } else {
 143                                         return false;
 144                                 }
 145                         }
 146
 147                         return true;
 148                 }
 149
 150                 #endregion
 151         }
 152
 153         //
 154         // The MemberCache is the main members container used by compiler. It contains
 155         // all members imported or defined during compilation using on demand filling
 156         // process. Inflated containers are also using MemberCache to make inflated
 157         // members look like normal definition.
 158         //
 159         // All of the methods are performance and memory sensitive as the MemberCache
 160         // is the underlying engine of all member based operations.
 161         //
 162         public class MemberCache
 163         {
 164                 [Flags]
 165                 enum StateFlags
 166                 {
 167                         HasConversionOperator = 1 << 1,
 168                         HasUserOperator = 1 << 2
 169                 }
 170
 171                 readonly Dictionary<string, IList<MemberSpec>> member_hash;
 172                 Dictionary<string, MemberSpec[]> locase_members;
 173                 IList<MethodSpec> missing_abstract;
 174                 StateFlags state;       // TODO: Move to TypeSpec or ITypeDefinition
 175
 176                 public static readonly string IndexerNameAlias = "<this>";
 177
 178                 public static readonly MemberCache Empty = new MemberCache (0);
 179
 180                 public MemberCache ()
 181                         : this (16)
 182                 {
 183                 }
 184
 185                 public MemberCache (int capacity)
 186                 {
 187                         member_hash = new Dictionary<string, IList<MemberSpec>> (capacity);
 188                 }
 189
 190                 public MemberCache (MemberCache cache)
 191                         : this (cache.member_hash.Count)
 192                 {
 193                         this.state = cache.state;
 194                 }
 195
 196                 //
 197                 // Creates a new MemberCache for the given `container'.
 198                 //
 199                 public MemberCache (TypeContainer container)
 200                         : this ()                               // TODO: Optimize the size
 201                 {
 202                 }
 203
 204                 //
 205                 // For cases where we need to union cache members
 206                 //
 207                 public void AddBaseType (TypeSpec baseType)
 208                 {
 209                         var cache = baseType.MemberCache;
 210
 211                         IList<MemberSpec> list;
 212                         foreach (var entry in cache.member_hash) {
 213                                 if (!member_hash.TryGetValue (entry.Key, out list)) {
 214                                         if (entry.Value.Count == 1) {
 215                                                 list = entry.Value;
 216                                         } else {
 217                                                 list = new List<MemberSpec> (entry.Value);
 218                                         }
 219
 220                                         member_hash.Add (entry.Key, list);
 221                                         continue;
 222                                 }
 223
 224                                 foreach (var ce in entry.Value) {
 225                                         if (list.Contains (ce))
 226                                                 continue;
 227
 228                                         if (list is MemberSpec[]) {
 229                                                 list = new List<MemberSpec> { list [0] };
 230                                                 member_hash[entry.Key] = list;
 231                                         }
 232
 233                                         list.Add (ce);
 234                                 }
 235                         }
 236                 }
 237
 238                 //
 239                 // Member-cache does not contain base members but it does
 240                 // contain all base interface members, so the Lookup code
 241                 // can use simple inheritance rules.
 242                 //
 243                 // Does not work recursively because of generic interfaces
 244                 //
 245                 public void AddInterface (TypeSpec iface)
 246                 {
 247                         var cache = iface.MemberCache;
 248
 249                         IList<MemberSpec> list;
 250                         foreach (var entry in cache.member_hash) {
 251                                 if (!member_hash.TryGetValue (entry.Key, out list)) {
 252                                         if (entry.Value.Count == 1) {
 253                                                 list = entry.Value;
 254                                         } else {
 255                                                 list = new List<MemberSpec> (entry.Value);
 256                                         }
 257
 258                                         member_hash.Add (entry.Key, list);
 259                                         continue;
 260                                 }
 261
 262                                 foreach (var ce in entry.Value) {
 263                                         //
 264                                         // When two or more different base interfaces implemenent common
 265                                         // interface
 266                                         //
 267                                         // I : IA, IFoo
 268                                         // IA : IFoo
 269                                         //
 270                                         if (list.Contains (ce))
 271                                                 continue;
 272
 273                                         if (AddInterfaceMember (ce, ref list))
 274                                                 member_hash[entry.Key] = list;
 275                                 }
 276                         }
 277                 }
 278
 279                 public void AddMember (InterfaceMemberBase imb, string exlicitName, MemberSpec ms)
 280                 {
 281                         // Explicit names cannot be looked-up but can be used for
 282                         // collision checking (no name mangling needed)
 283                         if (imb.IsExplicitImpl)
 284                                 AddMember (exlicitName, ms, false);
 285                         else
 286                                 AddMember (ms);
 287                 }
 288
 289                 //
 290                 // Add non-explicit member to member cache
 291                 //
 292                 public void AddMember (MemberSpec ms)
 293                 {
 294                         AddMember (GetLookupName (ms), ms, false);
 295                 }
 296
 297                 void AddMember (string name, MemberSpec member, bool removeHiddenMembers)
 298                 {
 299                         if (member.Kind == MemberKind.Operator) {
 300                                 var dt = member.DeclaringType;
 301
 302
 303                                 //
 304                                 // Some core types have user operators but they cannot be used like normal
 305                                 // user operators as they are predefined and therefore having different
 306                                 // rules (e.g. binary operators) by not setting the flag we hide them for
 307                                 // user conversions
 308                                 //
 309                                 if (!BuiltinTypeSpec.IsPrimitiveType (dt) || dt.BuiltinType == BuiltinTypeSpec.Type.Char) {
 310                                         switch (dt.BuiltinType) {
 311                                         case BuiltinTypeSpec.Type.String:
 312                                         case BuiltinTypeSpec.Type.Delegate:
 313                                         case BuiltinTypeSpec.Type.MulticastDelegate:
 314                                                 break;
 315                                         default:
 316                                                 if (name == Operator.GetMetadataName (Operator.OpType.Implicit) || name == Operator.GetMetadataName (Operator.OpType.Explicit)) {
 317                                                         state |= StateFlags.HasConversionOperator;
 318                                                 } else {
 319                                                         state |= StateFlags.HasUserOperator;
 320                                                 }
 321
 322                                                 break;
 323                                         }
 324                                 }
 325                         }
 326
 327                         IList<MemberSpec> list;
 328                         if (!member_hash.TryGetValue (name, out list)) {
 329                                 member_hash.Add (name, new MemberSpec[] { member });
 330                                 return;
 331                         }
 332
 333                         if (removeHiddenMembers && member.DeclaringType.IsInterface) {
 334                                 if (AddInterfaceMember (member, ref list))
 335                                         member_hash[name] = list;
 336                         } else {
 337                                 if (list.Count == 1) {
 338                                         list = new List<MemberSpec> { list[0] };
 339                                         member_hash[name] = list;
 340                                 }
 341
 342                                 list.Add (member);
 343                         }
 344                 }
 345
 346                 public void AddMemberImported (MemberSpec ms)
 347                 {
 348                         AddMember (GetLookupName (ms), ms, true);
 349                 }
 350
 351                 //
 352                 // Ignores any base interface member which can be hidden
 353                 // by this interface
 354                 //
 355                 static bool AddInterfaceMember (MemberSpec member, ref IList<MemberSpec> existing)
 356                 {
 357                         var member_param = member is IParametersMember ? ((IParametersMember) member).Parameters : ParametersCompiled.EmptyReadOnlyParameters;
 358
 359                         //
 360                         // interface IA : IB { int Prop { set; } }
 361                         // interface IB { bool Prop { get; } }
 362                         //
 363                         // IB.Prop is never accessible from IA interface
 364                         //
 365                         for (int i = 0; i < existing.Count; ++i) {
 366                                 var entry = existing[i];
 367
 368                                 if (entry.Arity != member.Arity)
 369                                         continue;
 370
 371                                 if (entry is IParametersMember) {
 372                                         var entry_param = ((IParametersMember) entry).Parameters;
 373                                         if (!TypeSpecComparer.Override.IsEqual (entry_param, member_param))
 374                                                 continue;
 375                                 }
 376
 377                                 if (member.DeclaringType.ImplementsInterface (entry.DeclaringType, false)) {
 378                                         if (existing.Count == 1) {
 379                                                 existing = new MemberSpec[] { member };
 380                                                 return true;
 381                                         }
 382
 383                                         existing.RemoveAt (i--);
 384                                         continue;
 385                                 }
 386
 387                                 if ((entry.DeclaringType == member.DeclaringType && entry.IsAccessor == member.IsAccessor) ||
 388                                         entry.DeclaringType.ImplementsInterface (member.DeclaringType, false))
 389                                         return false;
 390                         }
 391
 392                         if (existing.Count == 1) {
 393                                 existing = new List<MemberSpec> { existing[0], member };
 394                                 return true;
 395                         }
 396
 397                         existing.Add (member);
 398                         return false;
 399                 }
 400
 401                 public static MemberSpec FindMember (TypeSpec container, MemberFilter filter, BindingRestriction restrictions)
 402                 {
 403                         do {
 404                                 IList<MemberSpec> applicable;
 405                                 if (container.MemberCache.member_hash.TryGetValue (filter.Name, out applicable)) {
 406                                         // Start from the end because interface members are in reverse order
 407                                         for (int i = applicable.Count - 1; i >= 0; i--) {
 408                                                 var entry = applicable [i];
 409
 410                                                 if ((restrictions & BindingRestriction.InstanceOnly) != 0 && entry.IsStatic)
 411                                                         continue;
 412
 413                                                 if ((restrictions & BindingRestriction.NoAccessors) != 0 && entry.IsAccessor)
 414                                                         continue;
 415
 416                                                 if ((restrictions & BindingRestriction.OverrideOnly) != 0 && (entry.Modifiers & Modifiers.OVERRIDE) == 0)
 417                                                         continue;
 418
 419                                                 if (!filter.Equals (entry))
 420                                                         continue;
 421
 422                                                 if ((restrictions & BindingRestriction.DeclaredOnly) != 0 && container.IsInterface && entry.DeclaringType != container)
 423                                                         continue;
 424
 425                                                 return entry;
 426                                         }
 427                                 }
 428
 429                                 if ((restrictions & BindingRestriction.DeclaredOnly) != 0)
 430                                         break;
 431
 432                                 container = container.BaseType;
 433                         } while (container != null);
 434
 435                         return null;
 436                 }
 437
 438                 //
 439                 // A special method to work with member lookup only. It returns a list of all members named @name
 440                 // starting from @container. It's very performance sensitive
 441                 //
 442                 // declaredOnlyClass cannot be used interfaces. Manual filtering is required because names are
 443                 // compacted
 444                 //
 445                 public static IList<MemberSpec> FindMembers (TypeSpec container, string name, bool declaredOnlyClass)
 446                 {
 447                         IList<MemberSpec> applicable;
 448
 449                         do {
 450                                 if (container.MemberCache.member_hash.TryGetValue (name, out applicable) || declaredOnlyClass)
 451                                         return applicable;
 452
 453                                 container = container.BaseType;
 454                         } while (container != null);
 455
 456                         return null;
 457                 }
 458
 459                 //
 460                 // Finds the nested type in container
 461                 //
 462                 public static TypeSpec FindNestedType (TypeSpec container, string name, int arity)
 463                 {
 464                         IList<MemberSpec> applicable;
 465                         TypeSpec best_match = null;
 466                         do {
 467 #if !FULL_AOT_RUNTIME
 468                                 // TODO: Don't know how to handle this yet
 469                                 // When resolving base type of nested type, parent type must have
 470                                 // base type resolved to scan full hierarchy correctly
 471                                 // Similarly MemberCacheTypes will inflate BaseType and Interfaces
 472                                 // based on type definition
 473                                 var tc = container.MemberDefinition as TypeContainer;
 474                                 if (tc != null)
 475                                         tc.DefineContainer ();
 476 #endif
 477
 478                                 if (container.MemberCacheTypes.member_hash.TryGetValue (name, out applicable)) {
 479                                         for (int i = applicable.Count - 1; i >= 0; i--) {
 480                                                 var entry = applicable[i];
 481                                                 if ((entry.Kind & MemberKind.NestedMask) == 0)
 482                                                         continue;
 483
 484                                                 var ts = (TypeSpec) entry;
 485                                                 if (arity == ts.Arity)
 486                                                         return ts;
 487
 488                                                 if (arity < 0) {
 489                                                         if (best_match == null) {
 490                                                                 best_match = ts;
 491                                                         } else if (System.Math.Abs (ts.Arity + arity) < System.Math.Abs (ts.Arity + arity)) {
 492                                                                 best_match = ts;
 493                                                         }
 494                                                 }
 495                                         }
 496                                 }
 497
 498                                 container = container.BaseType;
 499                         } while (container != null);
 500
 501                         return best_match;
 502                 }
 503
 504                 //
 505                 // Looks for extension methods with defined name and extension type
 506                 //
 507                 public List<MethodSpec> FindExtensionMethods (IMemberContext invocationContext, string name, int arity)
 508                 {
 509                         IList<MemberSpec> entries;
 510                         if (!member_hash.TryGetValue (name, out entries))
 511                                 return null;
 512
 513                         List<MethodSpec> candidates = null;
 514                         foreach (var entry in entries) {
 515                                 if (entry.Kind != MemberKind.Method || (arity > 0 && entry.Arity != arity))
 516                                         continue;
 517
 518                                 var ms = (MethodSpec) entry;
 519                                 if (!ms.IsExtensionMethod)
 520                                         continue;
 521
 522                                 if (!ms.IsAccessible (invocationContext))
 523                                         continue;
 524
 525                                 //
 526                                 // Extension methods cannot be nested hence checking parent is enough
 527                                 //
 528                                 if ((ms.DeclaringType.Modifiers & Modifiers.INTERNAL) != 0 && !ms.DeclaringType.MemberDefinition.IsInternalAsPublic (invocationContext.Module.DeclaringAssembly))
 529                                         continue;
 530
 531                                 if (candidates == null)
 532                                         candidates = new List<MethodSpec> ();
 533                                 candidates.Add (ms);
 534                         }
 535
 536                         return candidates;
 537                 }
 538
 539                 //
 540                 // Returns base members of @member member if no exact match is found @bestCandidate returns
 541                 // the best match
 542                 //
 543                 public static MemberSpec FindBaseMember (MemberCore member, out MemberSpec bestCandidate, ref bool overrides)
 544                 {
 545                         bestCandidate = null;
 546                         var container = member.Parent.PartialContainer.Definition;
 547                         if (!container.IsInterface) {
 548                                 container = container.BaseType;
 549
 550                                 // It can happen for a user definition of System.Object
 551                                 if (container == null)
 552                                         return null;
 553                         }
 554
 555                         string name = GetLookupName (member);
 556                         var member_param = member is IParametersMember ? ((IParametersMember) member).Parameters : null;
 557
 558                         var mkind = GetMemberCoreKind (member);
 559                         bool member_with_accessors = mkind == MemberKind.Indexer || mkind == MemberKind.Property;
 560
 561                         IList<MemberSpec> applicable;
 562                         MemberSpec ambig_candidate = null;
 563
 564                         do {
 565                                 if (container.MemberCache.member_hash.TryGetValue (name, out applicable)) {
 566                                         for (int i = 0; i < applicable.Count; ++i) {
 567                                                 var entry = applicable [i];
 568
 569                                                 if ((entry.Modifiers & Modifiers.PUBLIC) == 0 && !entry.IsAccessible (member))
 570                                                         continue;
 571
 572                                                 //
 573                                                 // Isn't the member of same kind ?
 574                                                 //
 575                                                 if ((entry.Kind & ~MemberKind.Destructor & mkind & MemberKind.MaskType) == 0) {
 576                                                         // Destructors are ignored as they cannot be overridden by user
 577                                                         if ((entry.Kind & MemberKind.Destructor) != 0)
 578                                                                 continue;
 579
 580                                                         // A method with different arity does not hide base member
 581                                                         if (mkind != MemberKind.Method && member.MemberName.Arity != entry.Arity)
 582                                                                 continue;
 583
 584                                                         bestCandidate = entry;
 585                                                         return null;
 586                                                 }
 587
 588                                                 //
 589                                                 // Same kind of different arity is valid
 590                                                 //
 591                                                 if (member.MemberName.Arity != entry.Arity) {
 592                                                         continue;
 593                                                 }
 594
 595                                                 if ((entry.Kind & mkind & (MemberKind.Method | MemberKind.Indexer)) != 0) {
 596                                                         if (entry.IsAccessor != member is AbstractPropertyEventMethod)
 597                                                                 continue;
 598
 599                                                         var pm = entry as IParametersMember;
 600                                                         if (!TypeSpecComparer.Override.IsEqual (pm.Parameters, member_param))
 601                                                                 continue;
 602                                                 }
 603
 604                                                 //
 605                                                 // Skip override for member with accessors. It may not fully implement the base member
 606                                                 // but keep flag we found an implementation in case the base member is abstract
 607                                                 //
 608                                                 if (member_with_accessors && ((entry.Modifiers & (Modifiers.OVERRIDE | Modifiers.SEALED)) == Modifiers.OVERRIDE)) {
 609                                                         //
 610                                                         // Set candidate to override implementation to flag we found an implementation
 611                                                         //
 612                                                         overrides = true;
 613                                                         continue;
 614                                                 }
 615
 616                                                 //
 617                                                 // For members with parameters we can encounter an ambiguous candidates (they match exactly)
 618                                                 // because generic type parameters could be inflated into same types
 619                                                 //
 620                                                 if (ambig_candidate == null && (entry.Kind & mkind & (MemberKind.Method | MemberKind.Indexer)) != 0) {
 621                                                         bestCandidate = null;
 622                                                         ambig_candidate = entry;
 623                                                         continue;
 624                                                 }
 625
 626                                                 bestCandidate = ambig_candidate;
 627                                                 return entry;
 628                                         }
 629                                 }
 630
 631                                 if (container.IsInterface || ambig_candidate != null)
 632                                         break;
 633
 634                                 container = container.BaseType;
 635                         } while (container != null);
 636
 637                         return ambig_candidate;
 638                 }
 639
 640                 //
 641                 // Returns inflated version of MemberSpec, it works similarly to
 642                 // SRE TypeBuilder.GetMethod
 643                 //
 644                 public static T GetMember<T> (TypeSpec container, T spec) where T : MemberSpec
 645                 {
 646                         IList<MemberSpec> applicable;
 647                         if (container.MemberCache.member_hash.TryGetValue (GetLookupName (spec), out applicable)) {
 648                                 for (int i = applicable.Count - 1; i >= 0; i--) {
 649                                         var entry = applicable[i];
 650                                         if (entry.MemberDefinition == spec.MemberDefinition)
 651                                                 return (T) entry;
 652                                 }
 653                         }
 654
 655                         throw new InternalErrorException ("Missing member `{0}' on inflated type `{1}'",
 656                                 spec.GetSignatureForError (), container.GetSignatureForError ());
 657                 }
 658
 659                 static MemberKind GetMemberCoreKind (MemberCore member)
 660                 {
 661                         if (member is FieldBase)
 662                                 return MemberKind.Field;
 663                         if (member is Indexer)
 664                                 return MemberKind.Indexer;
 665                         if (member is Class)
 666                                 return MemberKind.Class;
 667                         if (member is Struct)
 668                                 return MemberKind.Struct;
 669                         if (member is Destructor)
 670                                 return MemberKind.Destructor;
 671                         if (member is Method)
 672                                 return MemberKind.Method;
 673                         if (member is Property)
 674                                 return MemberKind.Property;
 675                         if (member is EventField)
 676                                 return MemberKind.Event;
 677                         if (member is Interface)
 678                                 return MemberKind.Interface;
 679                         if (member is EventProperty)
 680                                 return MemberKind.Event;
 681                         if (member is Delegate)
 682                                 return MemberKind.Delegate;
 683                         if (member is Enum)
 684                                 return MemberKind.Enum;
 685
 686                         throw new NotImplementedException (member.GetType ().ToString ());
 687                 }
 688
 689                 public static List<FieldSpec> GetAllFieldsForDefiniteAssignment (TypeSpec container, IMemberContext context)
 690                 {
 691                         List<FieldSpec> fields = null;
 692                         bool imported = container.MemberDefinition.IsImported;
 693                         foreach (var entry in container.MemberCache.member_hash) {
 694                                 foreach (var name_entry in entry.Value) {
 695                                         if (name_entry.Kind != MemberKind.Field)
 696                                                 continue;
 697
 698                                         if ((name_entry.Modifiers & Modifiers.STATIC) != 0)
 699                                                 continue;
 700
 701                                         //
 702                                         // Fixed size buffers are not subject to definite assignment checking
 703                                         //
 704                                         if (name_entry is FixedFieldSpec || name_entry is ConstSpec)
 705                                                 continue;
 706
 707                                         var fs = (FieldSpec) name_entry;
 708                                         if (imported && ShouldIgnoreFieldForDefiniteAssignment (fs, context))
 709                                                 continue;
 710
 711                                         //if ((fs.Modifiers & (Modifiers.BACKING_FIELD) != 0)
 712                                         //      continue;
 713
 714                                         if (fields == null)
 715                                                 fields = new List<FieldSpec> ();
 716
 717                                         fields.Add (fs);
 718                                         break;
 719                                 }
 720                         }
 721
 722                         return fields ?? new List<FieldSpec> (0);
 723                 }
 724
 725                 static bool ShouldIgnoreFieldForDefiniteAssignment (FieldSpec fs, IMemberContext context)
 726                 {
 727                         //
 728                         // LAMESPEC: This mimics csc quirk where definitive assignment is not done
 729                         // for all kinds of imported non-public struct fields
 730                         //
 731                         var mod = fs.Modifiers;
 732                         if ((mod & Modifiers.PRIVATE) == 0 && ((mod & Modifiers.INTERNAL) != 0 && fs.DeclaringType.MemberDefinition.IsInternalAsPublic (context.Module.DeclaringAssembly)))
 733                                 return false;
 734
 735                         //
 736                         // Ignore reference type fields except when type is an array or type parameter
 737                         //
 738                         var type = fs.MemberType;
 739                         switch (type.Kind) {
 740                         case MemberKind.ArrayType:
 741                         case MemberKind.TypeParameter:
 742                                 return false;
 743                         default:
 744                                 return TypeSpec.IsReferenceType (type);
 745                         }
 746                 }
 747
 748                 public static IList<MemberSpec> GetCompletitionMembers (IMemberContext ctx, TypeSpec container, string name)
 749                 {
 750                         var matches = new List<MemberSpec> ();
 751                         foreach (var entry in container.MemberCache.member_hash) {
 752                                 foreach (var name_entry in entry.Value) {
 753                                         if (name_entry.IsAccessor)
 754                                                 continue;
 755
 756                                         if ((name_entry.Kind & (MemberKind.Constructor | MemberKind.Destructor | MemberKind.Operator)) != 0)
 757                                                 continue;
 758
 759                                         if (!name_entry.IsAccessible (ctx))
 760                                                 continue;
 761
 762                                         if (name == null || name_entry.Name.StartsWith (name)) {
 763                                                 matches.Add (name_entry);
 764                                         }
 765                                 }
 766                         }
 767
 768                         return matches;
 769                 }
 770
 771                 //
 772                 // Returns members of @iface only, base members are ignored
 773                 //
 774                 public static List<MethodSpec> GetInterfaceMethods (TypeSpec iface)
 775                 {
 776                         //
 777                         // MemberCache flatten interfaces, therefore in cases like this one
 778                         //
 779                         // interface IA : IB {}
 780                         // interface IB { void Foo () }
 781                         //
 782                         // we would return Foo inside IA which is not expected in this case
 783                         //
 784                         var methods = new List<MethodSpec> ();
 785                         foreach (var entry in iface.MemberCache.member_hash.Values) {
 786                                 foreach (var name_entry in entry) {
 787                                         if (iface == name_entry.DeclaringType) {
 788                                                 if (name_entry.Kind == MemberKind.Method) {
 789                                                         methods.Add ((MethodSpec) name_entry);
 790                                                 }
 791                                         }
 792                                 }
 793                         }
 794
 795                         return methods;
 796                 }
 797
 798                 //
 799                 // Returns all not implememted abstract members inside abstract type
 800                 // NOTE: Returned list is shared and must not be modified
 801                 //
 802                 public static IList<MethodSpec> GetNotImplementedAbstractMethods (TypeSpec type)
 803                 {
 804                         if (type.MemberCache.missing_abstract != null)
 805                                 return type.MemberCache.missing_abstract;
 806
 807                         var abstract_methods = new List<MethodSpec> ();
 808                         List<TypeSpec> hierarchy = null;
 809
 810                         //
 811                         // Stage 1: top-to-bottom scan for abstract members
 812                         //
 813                         var abstract_type = type;
 814                         while (true) {
 815                                 foreach (var entry in abstract_type.MemberCache.member_hash) {
 816                                         foreach (var name_entry in entry.Value) {
 817                                                 if ((name_entry.Modifiers & Modifiers.ABSTRACT) == 0)
 818                                                         continue;
 819
 820                                                 var ms = name_entry as MethodSpec;
 821                                                 if (ms == null)
 822                                                         continue;
 823
 824                                                 abstract_methods.Add (ms);
 825                                         }
 826                                 }
 827
 828                                 var base_type = abstract_type.BaseType;
 829                                 if (!base_type.IsAbstract)
 830                                         break;
 831
 832                                 if (hierarchy == null)
 833                                         hierarchy = new List<TypeSpec> ();
 834
 835                                 hierarchy.Add (abstract_type);
 836                                 abstract_type = base_type;
 837                         }
 838
 839                         int not_implemented_count = abstract_methods.Count;
 840                         if (not_implemented_count == 0 || hierarchy == null) {
 841                                 type.MemberCache.missing_abstract = abstract_methods;
 842                                 return type.MemberCache.missing_abstract;
 843                         }
 844
 845                         //
 846                         // Stage 2: Remove already implemented methods
 847                         //
 848                         foreach (var type_up in hierarchy) {
 849                                 var members = type_up.MemberCache.member_hash;
 850                                 if (members.Count == 0)
 851                                         continue;
 852
 853                                 for (int i = 0; i < abstract_methods.Count; ++i) {
 854                                         var candidate = abstract_methods [i];
 855                                         if (candidate == null)
 856                                                 continue;
 857
 858                                         IList<MemberSpec> applicable;
 859                                         if (!members.TryGetValue (candidate.Name, out applicable))
 860                                                 continue;
 861
 862                                         var filter = new MemberFilter (candidate);
 863                                         foreach (var item in applicable) {
 864                                                 if ((item.Modifiers & (Modifiers.OVERRIDE | Modifiers.VIRTUAL)) == 0)
 865                                                         continue;
 866
 867                                                 //
 868                                                 // Abstract override does not override anything
 869                                                 //
 870                                                 if ((item.Modifiers & Modifiers.ABSTRACT) != 0)
 871                                                         continue;
 872
 873                                                 if (filter.Equals (item)) {
 874                                                         --not_implemented_count;
 875                                                         abstract_methods [i] = null;
 876                                                         break;
 877                                                 }
 878                                         }
 879                                 }
 880                         }
 881
 882                         if (not_implemented_count == abstract_methods.Count) {
 883                                 type.MemberCache.missing_abstract = abstract_methods;
 884                                 return type.MemberCache.missing_abstract;
 885                         }
 886
 887                         var not_implemented = new MethodSpec[not_implemented_count];
 888                         int counter = 0;
 889                         foreach (var m in abstract_methods) {
 890                                 if (m == null)
 891                                         continue;
 892
 893                                 not_implemented[counter++] = m;
 894                         }
 895
 896                         type.MemberCache.missing_abstract = not_implemented;
 897                         return type.MemberCache.missing_abstract;
 898                 }
 899
 900                 static string GetLookupName (MemberSpec ms)
 901                 {
 902                         if (ms.Kind == MemberKind.Indexer)
 903                                 return IndexerNameAlias;
 904
 905                         if (ms.Kind == MemberKind.Constructor) {
 906                                 if (ms.IsStatic)
 907                                         return Constructor.TypeConstructorName;
 908
 909                                 return Constructor.ConstructorName;
 910                         }
 911
 912                         return ms.Name;
 913                 }
 914
 915                 static string GetLookupName (MemberCore mc)
 916                 {
 917                         if (mc is Indexer)
 918                                 return IndexerNameAlias;
 919
 920                         if (mc is Constructor)
 921                                 return mc.IsStatic ? Constructor.TypeConstructorName : Constructor.ConstructorName;
 922
 923                         return mc.MemberName.Name;
 924                 }
 925
 926                 //
 927                 // Returns all operators declared on container and its base types (until declaredOnly is used)
 928                 //
 929                 public static IList<MemberSpec> GetUserOperator (TypeSpec container, Operator.OpType op, bool declaredOnly)
 930                 {
 931                         IList<MemberSpec> found = null;
 932                         bool shared_list = true;
 933                         IList<MemberSpec> applicable;
 934                         do {
 935                                 var mc = container.MemberCache;
 936
 937                                 if (((op == Operator.OpType.Implicit || op == Operator.OpType.Explicit) && (mc.state & StateFlags.HasConversionOperator) != 0) ||
 938                                          (mc.state & StateFlags.HasUserOperator) != 0) {
 939
 940                                         if (mc.member_hash.TryGetValue (Operator.GetMetadataName (op), out applicable)) {
 941                                                 int i;
 942                                                 for (i = 0; i < applicable.Count; ++i) {
 943                                                         if (applicable[i].Kind != MemberKind.Operator) {
 944                                                                 break;
 945                                                         }
 946                                                 }
 947
 948                                                 //
 949                                                 // Handles very rare case where a method with same name as operator (op_xxxx) exists
 950                                                 // and we have to resize the applicable list
 951                                                 //
 952                                                 if (i != applicable.Count) {
 953                                                         for (i = 0; i < applicable.Count; ++i) {
 954                                                                 if (applicable[i].Kind != MemberKind.Operator) {
 955                                                                         continue;
 956                                                                 }
 957
 958                                                                 if (found == null) {
 959                                                                         found = new List<MemberSpec> ();
 960                                                                         found.Add (applicable[i]);
 961                                                                 } else {
 962                                                                         List<MemberSpec> prev;
 963                                                                         if (shared_list) {
 964                                                                                 shared_list = false;
 965                                                                                 prev = new List<MemberSpec> (found.Count + 1);
 966                                                                                 prev.AddRange (found);
 967                                                                         } else {
 968                                                                                 prev = (List<MemberSpec>) found;
 969                                                                         }
 970
 971                                                                         prev.Add (applicable[i]);
 972                                                                 }
 973                                                         }
 974                                                 } else {
 975                                                         if (found == null) {
 976                                                                 found = applicable;
 977                                                                 shared_list = true;
 978                                                         } else {
 979                                                                 List<MemberSpec> merged;
 980                                                                 if (shared_list) {
 981                                                                         shared_list = false;
 982                                                                         merged = new List<MemberSpec> (found.Count + applicable.Count);
 983                                                                         merged.AddRange (found);
 984                                                                         found = merged;
 985                                                                 } else {
 986                                                                         merged = (List<MemberSpec>) found;
 987                                                                 }
 988
 989                                                                 merged.AddRange (applicable);
 990                                                         }
 991                                                 }
 992                                         }
 993                                 }
 994
 995                                 // BaseType call can be expensive
 996                                 if (declaredOnly)
 997                                         break;
 998
 999                                 container = container.BaseType;
1000                         } while (container != null);
1001
1002                         return found;
1003                 }
1004
1005                 //
1006                 // Inflates all member cache nested types
1007                 //
1008                 public void InflateTypes (MemberCache inflated_cache, TypeParameterInflator inflator)
1009                 {
1010                         foreach (var item in member_hash) {
1011                                 IList<MemberSpec> inflated_members = null;
1012                                 for (int i = 0; i < item.Value.Count; ++i ) {
1013                                         var member = item.Value[i];
1014
1015                                         // FIXME: When inflating members refering nested types before they are inflated
1016                                         if (member == null)
1017                                                 continue;
1018
1019                                         if ((member.Kind & MemberKind.NestedMask) != 0 &&
1020                                                 (member.Modifiers & Modifiers.COMPILER_GENERATED) == 0) {
1021                                                 if (inflated_members == null) {
1022                                                         inflated_members = new MemberSpec[item.Value.Count];
1023                                                         inflated_cache.member_hash.Add (item.Key, inflated_members);
1024                                                 }
1025
1026                                                 inflated_members [i] = member.InflateMember (inflator);
1027                                         }
1028                                 }
1029                         }
1030                 }
1031
1032                 //
1033                 // Inflates all open type members, requires InflateTypes to be called before
1034                 //
1035                 public void InflateMembers (MemberCache cacheToInflate, TypeSpec inflatedType, TypeParameterInflator inflator)
1036                 {
1037                         var inflated_member_hash = cacheToInflate.member_hash;
1038                         Dictionary<MemberSpec, MethodSpec> accessor_relation = null;
1039                         List<MemberSpec> accessor_members = null;
1040
1041                         // Copy member specific flags when all members were added
1042                         cacheToInflate.state = state;
1043
1044                         foreach (var item in member_hash) {
1045                                 var members = item.Value;
1046                                 IList<MemberSpec> inflated_members = null;
1047                                 for (int i = 0; i < members.Count; ++i ) {
1048                                         var member = members[i];
1049
1050                                         //
1051                                         // All nested types have been inflated earlier except for
1052                                         // compiler types which are created later and could miss InflateTypes
1053                                         //
1054                                         if ((member.Kind & MemberKind.NestedMask) != 0 &&
1055                                                 (member.Modifiers & Modifiers.COMPILER_GENERATED) == 0) {
1056                                                 if (inflated_members == null)
1057                                                         inflated_members = inflated_member_hash[item.Key];
1058
1059                                                 continue;
1060                                         }
1061
1062                                         //
1063                                         // Clone the container first
1064                                         //
1065                                         if (inflated_members == null) {
1066                                                 inflated_members = new MemberSpec [item.Value.Count];
1067                                                 inflated_member_hash.Add (item.Key, inflated_members);
1068                                         }
1069
1070                                         var local_inflator = inflator;
1071
1072                                         if (member.DeclaringType != inflatedType) {
1073                                                 //
1074                                                 // Don't inflate top-level non-generic interface members
1075                                                 // merged into generic interface
1076                                                 //
1077                                                 if (!member.DeclaringType.IsGeneric && !member.DeclaringType.IsNested) {
1078                                                         inflated_members [i] = member;
1079                                                         continue;
1080                                                 }
1081
1082                                                 //
1083                                                 // Needed when inflating flatten interfaces. It inflates
1084                                                 // container type only, type parameters are already done
1085                                                 //
1086                                                 // Handles cases like:
1087                                                 //
1088                                                 // interface I<T> {}
1089                                                 // interface I<U, V> : I<U> {}
1090                                                 //
1091                                                 // class C: I<int, bool> {}
1092                                                 //
1093                                                 var inflated_parent = inflator.Inflate (member.DeclaringType);
1094                                                 if (inflated_parent != inflator.TypeInstance)
1095                                                         local_inflator = new TypeParameterInflator (inflator, inflated_parent);
1096                                         }
1097
1098                                         //
1099                                         // Inflate every member, its parent is now different
1100                                         //
1101                                         var inflated = member.InflateMember (local_inflator);
1102                                         inflated_members [i] = inflated;
1103
1104                                         if (member is PropertySpec || member is EventSpec) {
1105                                                 if (accessor_members == null)
1106                                                         accessor_members = new List<MemberSpec> ();
1107
1108                                                 accessor_members.Add (inflated);
1109                                                 continue;
1110                                         }
1111
1112                                         if (member.IsAccessor) {
1113                                                 if (accessor_relation == null)
1114                                                         accessor_relation = new Dictionary<MemberSpec, MethodSpec> ();
1115                                                 accessor_relation.Add (member, (MethodSpec) inflated);
1116                                         }
1117                                 }
1118                         }
1119
1120                         if (accessor_members != null) {
1121                                 foreach (var member in accessor_members) {
1122                                         var prop = member as PropertySpec;
1123                                         if (prop != null) {
1124                                                 if (prop.Get != null)
1125                                                         prop.Get = accessor_relation[prop.Get];
1126                                                 if (prop.Set != null)
1127                                                         prop.Set = accessor_relation[prop.Set];
1128
1129                                                 continue;
1130                                         }
1131
1132                                         var ev = (EventSpec) member;
1133                                         ev.AccessorAdd = accessor_relation[ev.AccessorAdd];
1134                                         ev.AccessorRemove = accessor_relation[ev.AccessorRemove];
1135                                 }
1136                         }
1137                 }
1138
1139                 //
1140                 // Removes hidden base members of an interface. For compiled interfaces we cannot
1141                 // do name filtering during Add (as we do for import) because we need all base
1142                 // names to be valid during type definition.
1143                 // Add replaces hidden base member with current one which means any name collision
1144                 // (CS0108) of non-first name would be unnoticed because the name was replaced
1145                 // with the one from compiled type
1146                 //
1147                 public void RemoveHiddenMembers (TypeSpec container)
1148                 {
1149                         foreach (var entry in member_hash) {
1150                                 var values = entry.Value;
1151
1152                                 int container_members_start_at = 0;
1153                                 while (values[container_members_start_at].DeclaringType != container && ++container_members_start_at < entry.Value.Count);
1154
1155                                 if (container_members_start_at == 0 || container_members_start_at == values.Count)
1156                                         continue;
1157
1158                                 for (int i = 0; i < container_members_start_at; ++i) {
1159                                         var member = values[i];
1160
1161                                         if (!container.ImplementsInterface (member.DeclaringType, false))
1162                                                 continue;
1163
1164                                         var member_param = member is IParametersMember ? ((IParametersMember) member).Parameters : ParametersCompiled.EmptyReadOnlyParameters;
1165
1166                                         for (int ii = container_members_start_at; ii < values.Count; ++ii) {
1167                                                 var container_entry = values[ii];
1168
1169                                                 if (container_entry.Arity != member.Arity)
1170                                                         continue;
1171
1172                                                 if (container_entry is IParametersMember) {
1173                                                         if (!TypeSpecComparer.Override.IsEqual (((IParametersMember) container_entry).Parameters, member_param))
1174                                                                 continue;
1175                                                 }
1176
1177                                                 values.RemoveAt (i);
1178                                                 --container_members_start_at;
1179                                                 --ii;
1180                                                 --i;
1181                                         }
1182                                 }
1183                         }
1184                 }
1185
1186                 //
1187                 // Checks all appropriate container members for CLS compliance
1188                 //
1189                 public void VerifyClsCompliance (TypeSpec container, Report report)
1190                 {
1191                         if (locase_members != null)
1192                                 return;
1193
1194                         if (container.BaseType == null) {
1195                                 locase_members = new Dictionary<string, MemberSpec[]> (member_hash.Count); // StringComparer.OrdinalIgnoreCase);
1196                         } else {
1197                                 var btype = container.BaseType.GetDefinition ();
1198                                 btype.MemberCache.VerifyClsCompliance (btype, report);
1199                                 locase_members = new Dictionary<string, MemberSpec[]> (btype.MemberCache.locase_members); //, StringComparer.OrdinalIgnoreCase);
1200                         }
1201
1202                         var is_imported_type = container.MemberDefinition.IsImported;
1203                         foreach (var entry in container.MemberCache.member_hash) {
1204                                 for (int i = 0; i < entry.Value.Count; ++i ) {
1205                                         var name_entry = entry.Value[i];
1206                                         if ((name_entry.Modifiers & (Modifiers.PUBLIC | Modifiers.PROTECTED)) == 0)
1207                                                 continue;
1208
1209                                         if ((name_entry.Modifiers & (Modifiers.OVERRIDE | Modifiers.COMPILER_GENERATED)) != 0)
1210                                                 continue;
1211
1212                                         if ((name_entry.Kind & MemberKind.MaskType) == 0)
1213                                                 continue;
1214
1215                                         if (name_entry.MemberDefinition.CLSAttributeValue == false)
1216                                             continue;
1217
1218                                         IParametersMember p_a = null;
1219                                         if (!is_imported_type) {
1220                                                 p_a = name_entry as IParametersMember;
1221                                                 if (p_a != null && !name_entry.IsAccessor) {
1222                                                         var p_a_pd = p_a.Parameters;
1223                                                         //
1224                                                         // Check differing overloads in @container
1225                                                         //
1226                                                         for (int ii = i + 1; ii < entry.Value.Count; ++ii) {
1227                                                                 var checked_entry = entry.Value[ii];
1228                                                                 IParametersMember p_b = checked_entry as IParametersMember;
1229                                                                 if (p_b == null)
1230                                                                         continue;
1231
1232                                                                 if (p_a_pd.Count != p_b.Parameters.Count)
1233                                                                         continue;
1234
1235                                                                 if (checked_entry.IsAccessor)
1236                                                                         continue;
1237
1238                                                                 var res = ParametersCompiled.IsSameClsSignature (p_a.Parameters, p_b.Parameters);
1239                                                                 if (res != 0) {
1240                                                                         ReportOverloadedMethodClsDifference (name_entry, checked_entry, res, report);
1241                                                                 }
1242                                                         }
1243                                                 }
1244                                         }
1245
1246                                         if (i > 0 || name_entry.Kind == MemberKind.Constructor || name_entry.Kind == MemberKind.Indexer)
1247                                                 continue;
1248
1249                                         var name_entry_locase = name_entry.Name.ToLowerInvariant ();
1250
1251                                         MemberSpec[] found;
1252                                         if (!locase_members.TryGetValue (name_entry_locase, out found)) {
1253                                                 found = new MemberSpec[] { name_entry };
1254                                                 locase_members.Add (name_entry_locase, found);
1255                                         } else {
1256                                                 bool same_names_only = true;
1257                                                 foreach (var f in found) {
1258                                                         if (f.Name == name_entry.Name) {
1259                                                                 if (p_a != null) {
1260                                                                         IParametersMember p_b = f as IParametersMember;
1261                                                                         if (p_b == null)
1262                                                                                 continue;
1263
1264                                                                         if (p_a.Parameters.Count != p_b.Parameters.Count)
1265                                                                                 continue;
1266
1267                                                                         if (f.IsAccessor)
1268                                                                                 continue;
1269
1270                                                                         var res = ParametersCompiled.IsSameClsSignature (p_a.Parameters, p_b.Parameters);
1271                                                                         if (res != 0) {
1272                                                                                 ReportOverloadedMethodClsDifference (f, name_entry, res, report);
1273                                                                         }
1274                                                                 }
1275
1276                                                                 continue;
1277                                                         }
1278
1279                                                         same_names_only = false;
1280                                                         if (!is_imported_type) {
1281                                                                 var last = GetLaterDefinedMember (f, name_entry);
1282                                                                 if (last == f.MemberDefinition) {
1283                                                                         report.SymbolRelatedToPreviousError (name_entry);
1284                                                                 } else {
1285                                                                         report.SymbolRelatedToPreviousError (f);
1286                                                                 }
1287
1288                                                                 report.Warning (3005, 1, last.Location,
1289                                                                         "Identifier `{0}' differing only in case is not CLS-compliant", last.GetSignatureForError ());
1290                                                         }
1291                                                 }
1292
1293                                                 if (!same_names_only) {
1294                                                         Array.Resize (ref found, found.Length + 1);
1295                                                         found[found.Length - 1] = name_entry;
1296                                                         locase_members[name_entry_locase] = found;
1297                                                 }
1298                                         }
1299                                 }
1300                         }
1301                 }
1302
1303                 //
1304                 // Local report helper to issue correctly ordered members stored in hashtable
1305                 //
1306                 static MemberCore GetLaterDefinedMember (MemberSpec a, MemberSpec b)
1307                 {
1308                         var mc_a = a.MemberDefinition as MemberCore;
1309                         var mc_b = b.MemberDefinition as MemberCore;
1310                         if (mc_a == null)
1311                                 return mc_b;
1312
1313                         if (mc_b == null)
1314                                 return mc_a;
1315
1316                         if (a.DeclaringType.MemberDefinition != b.DeclaringType.MemberDefinition)
1317                                 return mc_b;
1318
1319                         if (mc_a.Location.File != mc_a.Location.File)
1320                                 return mc_b;
1321
1322                         return mc_b.Location.Row > mc_a.Location.Row ? mc_b : mc_a;
1323                 }
1324
1325                 static void ReportOverloadedMethodClsDifference (MemberSpec a, MemberSpec b, int res, Report report)
1326                 {
1327                         var last = GetLaterDefinedMember (a, b);
1328                         if (last == a.MemberDefinition) {
1329                                 report.SymbolRelatedToPreviousError (b);
1330                         } else {
1331                                 report.SymbolRelatedToPreviousError (a);
1332                         }
1333
1334                         if ((res & 1) != 0) {
1335                                 report.Warning (3006, 1, last.Location,
1336                                                 "Overloaded method `{0}' differing only in ref or out, or in array rank, is not CLS-compliant",
1337                                                 last.GetSignatureForError ());
1338                         }
1339
1340                         if ((res & 2) != 0) {
1341                                 report.Warning (3007, 1, last.Location,
1342                                         "Overloaded method `{0}' differing only by unnamed array types is not CLS-compliant",
1343                                         last.GetSignatureForError ());
1344                         }
1345                 }
1346
1347                 public bool CheckExistingMembersOverloads (MemberCore member, AParametersCollection parameters)
1348                 {
1349                         var name = GetLookupName (member);
1350                         var imb = member as InterfaceMemberBase;
1351                         if (imb != null && imb.IsExplicitImpl) {
1352                                 name = imb.GetFullName (name);
1353                         }
1354
1355                         return CheckExistingMembersOverloads (member, name, parameters);
1356                 }
1357
1358                 public bool CheckExistingMembersOverloads (MemberCore member, string name, AParametersCollection parameters)
1359                 {
1360                         IList<MemberSpec> entries;
1361                         if (!member_hash.TryGetValue (name, out entries))
1362                                 return false;
1363
1364                         var Report = member.Compiler.Report;
1365
1366                         int method_param_count = parameters.Count;
1367                         for (int i = entries.Count - 1; i >= 0; --i) {
1368                                 var ce = entries[i];
1369                                 var pm = ce as IParametersMember;
1370                                 var pd = pm == null ? ParametersCompiled.EmptyReadOnlyParameters : pm.Parameters;
1371                                 if (pd.Count != method_param_count)
1372                                         continue;
1373
1374                                 if (ce.Arity != member.MemberName.Arity)
1375                                         continue;
1376
1377                                 // Ignore merged interface members
1378                                 if (member.Parent.PartialContainer != ce.DeclaringType.MemberDefinition)
1379                                         continue;
1380
1381                                 var p_types = pd.Types;
1382                                 if (method_param_count > 0) {
1383                                         int ii = method_param_count - 1;
1384                                         TypeSpec type_a, type_b;
1385                                         do {
1386                                                 type_a = parameters.Types [ii];
1387                                                 type_b = p_types [ii];
1388
1389                                                 var a_byref = (pd.FixedParameters[ii].ModFlags & Parameter.Modifier.RefOutMask) != 0;
1390                                                 var b_byref = (parameters.FixedParameters[ii].ModFlags & Parameter.Modifier.RefOutMask) != 0;
1391
1392                                                 if (a_byref != b_byref)
1393                                                         break;
1394
1395                                         } while (TypeSpecComparer.Override.IsEqual (type_a, type_b) && ii-- != 0);
1396
1397                                         if (ii >= 0)
1398                                                 continue;
1399
1400                                         //
1401                                         // Operators can differ in return type only
1402                                         //
1403                                         if (member is Operator && ce.Kind == MemberKind.Operator && ((MethodSpec) ce).ReturnType != ((Operator) member).ReturnType)
1404                                                 continue;
1405
1406                                         //
1407                                         // Report difference in parameter modifiers only
1408                                         //
1409                                         if (pd != null && member is MethodCore) {
1410                                                 ii = method_param_count;
1411                                                 while (ii-- != 0 &&
1412                                                         (parameters.FixedParameters[ii].ModFlags & Parameter.Modifier.ModifierMask) ==
1413                                                         (pd.FixedParameters[ii].ModFlags & Parameter.Modifier.ModifierMask) &&
1414                                                         parameters.ExtensionMethodType == pd.ExtensionMethodType) ;
1415
1416                                                 if (ii >= 0) {
1417                                                         var mc = ce as MethodSpec;
1418                                                         member.Compiler.Report.SymbolRelatedToPreviousError (ce);
1419                                                         if ((member.ModFlags & Modifiers.PARTIAL) != 0 && (mc.Modifiers & Modifiers.PARTIAL) != 0) {
1420                                                                 if (parameters.HasParams || pd.HasParams) {
1421                                                                         Report.Error (758, member.Location,
1422                                                                                 "A partial method declaration and partial method implementation cannot differ on use of `params' modifier");
1423                                                                 } else {
1424                                                                         Report.Error (755, member.Location,
1425                                                                                 "A partial method declaration and partial method implementation must be both an extension method or neither");
1426                                                                 }
1427                                                         } else if (member is Constructor) {
1428                                                                 Report.Error (851, member.Location,
1429                                                                         "Overloaded contructor `{0}' cannot differ on use of parameter modifiers only",
1430                                                                         member.GetSignatureForError ());
1431                                                         } else {
1432                                                                 Report.Error (663, member.Location,
1433                                                                         "Overloaded method `{0}' cannot differ on use of parameter modifiers only",
1434                                                                         member.GetSignatureForError ());
1435                                                         }
1436                                                         return false;
1437                                                 }
1438                                         }
1439                                 }
1440
1441                                 if ((ce.Kind & MemberKind.Method) != 0) {
1442                                         Method method_a = member as Method;
1443                                         Method method_b = ce.MemberDefinition as Method;
1444                                         if (method_a != null && method_b != null && (method_a.ModFlags & method_b.ModFlags & Modifiers.PARTIAL) != 0) {
1445                                                 const Modifiers partial_modifiers = Modifiers.STATIC | Modifiers.UNSAFE;
1446                                                 if (method_a.IsPartialDefinition == method_b.IsPartialImplementation) {
1447                                                         if ((method_a.ModFlags & partial_modifiers) == (method_b.ModFlags & partial_modifiers) ||
1448                                                                 method_a.Parent.IsUnsafe && method_b.Parent.IsUnsafe) {
1449                                                                 if (method_a.IsPartialImplementation) {
1450                                                                         method_a.SetPartialDefinition (method_b);
1451                                                                         if (entries.Count == 1)
1452                                                                                 member_hash.Remove (name);
1453                                                                         else
1454                                                                                 entries.RemoveAt (i);
1455                                                                 } else {
1456                                                                         method_b.SetPartialDefinition (method_a);
1457                                                                         method_a.caching_flags |= MemberCore.Flags.PartialDefinitionExists;
1458                                                                 }
1459                                                                 continue;
1460                                                         }
1461
1462                                                         if (method_a.IsStatic != method_b.IsStatic) {
1463                                                                 Report.SymbolRelatedToPreviousError (ce);
1464                                                                 Report.Error (763, member.Location,
1465                                                                         "A partial method declaration and partial method implementation must be both `static' or neither");
1466                                                         }
1467
1468                                                         if ((method_a.ModFlags & Modifiers.UNSAFE) != (method_b.ModFlags & Modifiers.UNSAFE)) {
1469                                                                 Report.SymbolRelatedToPreviousError (ce);
1470                                                                 Report.Error (764, member.Location,
1471                                                                         "A partial method declaration and partial method implementation must be both `unsafe' or neither");
1472                                                         }
1473
1474                                                         return false;
1475                                                 }
1476
1477                                                 Report.SymbolRelatedToPreviousError (ce);
1478                                                 if (method_a.IsPartialDefinition) {
1479                                                         Report.Error (756, member.Location, "A partial method `{0}' declaration is already defined",
1480                                                                 member.GetSignatureForError ());
1481                                                 }
1482
1483                                                 Report.Error (757, member.Location, "A partial method `{0}' implementation is already defined",
1484                                                         member.GetSignatureForError ());
1485                                                 return false;
1486                                         }
1487
1488                                         Report.SymbolRelatedToPreviousError (ce);
1489
1490                                         bool is_reserved_a = member is AbstractPropertyEventMethod || member is Operator;
1491                                         bool is_reserved_b = ((MethodSpec) ce).IsReservedMethod;
1492
1493                                         if (is_reserved_a || is_reserved_b) {
1494                                                 Report.Error (82, member.Location, "A member `{0}' is already reserved",
1495                                                         is_reserved_a ?
1496                                                         ce.GetSignatureForError () :
1497                                                         member.GetSignatureForError ());
1498                                                 return false;
1499                                         }
1500                                 } else {
1501                                         Report.SymbolRelatedToPreviousError (ce);
1502                                 }
1503
1504                                 if (member is Operator && ce.Kind == MemberKind.Operator) {
1505                                         Report.Error (557, member.Location, "Duplicate user-defined conversion in type `{0}'",
1506                                                 member.Parent.GetSignatureForError ());
1507                                         return false;
1508                                 }
1509
1510                                 Report.Error (111, member.Location,
1511                                         "A member `{0}' is already defined. Rename this member or use different parameter types",
1512                                         member.GetSignatureForError ());
1513                                 return false;
1514                         }
1515
1516                         return true;
1517                 }
1518         }
1519 }