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