2 // field.cs: All field handlers
4 // Authors: Miguel de Icaza (miguel@gnu.org)
5 // Martin Baulig (martin@ximian.com)
6 // Marek Safar (marek.safar@seznam.cz)
8 // Dual licensed under the terms of the MIT X11 or GNU GPL
10 // Copyright 2001, 2002, 2003 Ximian, Inc (http://www.ximian.com)
11 // Copyright 2004-2008 Novell, Inc
12 // Copyright 2011 Xamarin Inc
16 using System.Collections.Generic;
17 using System.Runtime.InteropServices;
20 using MetaType = IKVM.Reflection.Type;
21 using IKVM.Reflection;
22 using IKVM.Reflection.Emit;
24 using MetaType = System.Type;
25 using System.Reflection;
26 using System.Reflection.Emit;
31 public class FieldDeclarator
33 public FieldDeclarator (SimpleMemberName name, Expression initializer)
36 this.Initializer = initializer;
41 public SimpleMemberName Name { get; private set; }
42 public Expression Initializer { get; private set; }
46 public virtual FullNamedExpression GetFieldTypeExpression (FieldBase field)
48 return new TypeExpression (field.MemberType, Name.Location);
53 // Abstract class for all fields
55 abstract public class FieldBase : MemberBase
57 protected FieldBuilder FieldBuilder;
58 protected FieldSpec spec;
60 protected Expression initializer;
61 protected List<FieldDeclarator> declarators;
64 public enum Status : byte {
65 HAS_OFFSET = 4 // Used by FieldMember.
68 static readonly string[] attribute_targets = new string [] { "field" };
70 protected FieldBase (TypeDefinition parent, FullNamedExpression type, Modifiers mod, Modifiers allowed_mod, MemberName name, Attributes attrs)
71 : base (parent, type, mod, allowed_mod | Modifiers.ABSTRACT, Modifiers.PRIVATE, name, attrs)
73 if ((mod & Modifiers.ABSTRACT) != 0)
74 Report.Error (681, Location, "The modifier 'abstract' is not valid on fields. Try using a property instead");
79 public override AttributeTargets AttributeTargets {
81 return AttributeTargets.Field;
85 public List<FieldDeclarator> Declarators {
87 return this.declarators;
91 public Expression Initializer {
96 this.initializer = value;
102 return MemberName.Name;
106 public FieldSpec Spec {
112 public override string[] ValidAttributeTargets {
114 return attribute_targets;
120 public void AddDeclarator (FieldDeclarator declarator)
122 if (declarators == null)
123 declarators = new List<FieldDeclarator> (2);
125 declarators.Add (declarator);
127 Parent.AddNameToContainer (this, declarator.Name.Value);
130 public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
132 if (a.Type == pa.FieldOffset) {
133 status |= Status.HAS_OFFSET;
135 if (!Parent.PartialContainer.HasExplicitLayout) {
136 Report.Error (636, Location, "The FieldOffset attribute can only be placed on members of types marked with the StructLayout(LayoutKind.Explicit)");
140 if ((ModFlags & Modifiers.STATIC) != 0 || this is Const) {
141 Report.Error (637, Location, "The FieldOffset attribute is not allowed on static or const fields");
146 if (a.Type == pa.FixedBuffer) {
147 Report.Error (1716, Location, "Do not use 'System.Runtime.CompilerServices.FixedBuffer' attribute. Use the 'fixed' field modifier instead");
152 if (a.Type == pa.MarshalAs) {
153 UnmanagedMarshal marshal = a.GetMarshal (this);
154 if (marshal != null) {
155 FieldBuilder.SetMarshal (marshal);
160 if ((a.HasSecurityAttribute)) {
161 a.Error_InvalidSecurityParent ();
165 if (a.Type == pa.Dynamic) {
166 a.Error_MisusedDynamicAttribute ();
170 FieldBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), cdata);
173 public void SetCustomAttribute (MethodSpec ctor, byte[] data)
175 FieldBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), data);
178 protected override bool CheckBase ()
180 if (!base.CheckBase ())
183 MemberSpec candidate;
184 bool overrides = false;
185 var conflict_symbol = MemberCache.FindBaseMember (this, out candidate, ref overrides);
186 if (conflict_symbol == null)
187 conflict_symbol = candidate;
189 if (conflict_symbol == null) {
190 if ((ModFlags & Modifiers.NEW) != 0) {
191 Report.Warning (109, 4, Location, "The member `{0}' does not hide an inherited member. The new keyword is not required",
192 GetSignatureForError ());
195 if ((ModFlags & (Modifiers.NEW | Modifiers.OVERRIDE | Modifiers.BACKING_FIELD)) == 0) {
196 Report.SymbolRelatedToPreviousError (conflict_symbol);
197 Report.Warning (108, 2, Location, "`{0}' hides inherited member `{1}'. Use the new keyword if hiding was intended",
198 GetSignatureForError (), conflict_symbol.GetSignatureForError ());
201 if (conflict_symbol.IsAbstract) {
202 Report.SymbolRelatedToPreviousError (conflict_symbol);
203 Report.Error (533, Location, "`{0}' hides inherited abstract member `{1}'",
204 GetSignatureForError (), conflict_symbol.GetSignatureForError ());
211 public virtual Constant ConvertInitializer (ResolveContext rc, Constant expr)
213 return expr.ConvertImplicitly (MemberType);
216 protected override void DoMemberTypeDependentChecks ()
218 base.DoMemberTypeDependentChecks ();
220 if (MemberType.IsGenericParameter)
223 if (MemberType.IsStatic)
224 Error_VariableOfStaticClass (Location, GetSignatureForError (), MemberType, Report);
226 if (!IsCompilerGenerated)
233 // Represents header string for documentation comment.
235 public override string DocCommentHeader {
239 public override void Emit ()
241 if (member_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic) {
242 Module.PredefinedAttributes.Dynamic.EmitAttribute (FieldBuilder);
243 } else if (!Parent.IsCompilerGenerated && member_type.HasDynamicElement) {
244 Module.PredefinedAttributes.Dynamic.EmitAttribute (FieldBuilder, member_type, Location);
247 if (member_type.HasNamedTupleElement) {
248 Module.PredefinedAttributes.TupleElementNames.EmitAttribute (FieldBuilder, member_type, Location);
251 if ((ModFlags & Modifiers.COMPILER_GENERATED) != 0 && !Parent.IsCompilerGenerated)
252 Module.PredefinedAttributes.CompilerGenerated.EmitAttribute (FieldBuilder);
253 if ((ModFlags & Modifiers.DEBUGGER_HIDDEN) != 0)
254 Module.PredefinedAttributes.DebuggerBrowsable.EmitAttribute (FieldBuilder, System.Diagnostics.DebuggerBrowsableState.Never);
256 if (OptAttributes != null) {
257 OptAttributes.Emit ();
260 if (((status & Status.HAS_OFFSET) == 0) && (ModFlags & (Modifiers.STATIC | Modifiers.BACKING_FIELD)) == 0 && Parent.PartialContainer.HasExplicitLayout) {
261 Report.Error (625, Location, "`{0}': Instance field types marked with StructLayout(LayoutKind.Explicit) must have a FieldOffset attribute", GetSignatureForError ());
264 if (!IsCompilerGenerated)
265 ConstraintChecker.Check (this, member_type, type_expr.Location);
270 public static void Error_VariableOfStaticClass (Location loc, string variable_name, TypeSpec static_class, Report Report)
272 Report.SymbolRelatedToPreviousError (static_class);
273 Report.Error (723, loc, "`{0}': cannot declare variables of static types",
277 protected override bool VerifyClsCompliance ()
279 if (!base.VerifyClsCompliance ())
282 if (!MemberType.IsCLSCompliant () || this is FixedField) {
283 Report.Warning (3003, 1, Location, "Type of `{0}' is not CLS-compliant",
284 GetSignatureForError ());
291 // Field specification
293 public class FieldSpec : MemberSpec, IInterfaceMemberSpec
298 public FieldSpec (TypeSpec declaringType, IMemberDefinition definition, TypeSpec memberType, FieldInfo info, Modifiers modifiers)
299 : base (MemberKind.Field, declaringType, definition, modifiers)
301 this.metaInfo = info;
302 this.memberType = memberType;
307 public bool IsReadOnly {
309 return (Modifiers & Modifiers.READONLY) != 0;
313 public TypeSpec MemberType {
321 public FieldInfo GetMetaInfo ()
323 if ((state & StateFlags.PendingMetaInflate) != 0) {
324 var decl_meta = DeclaringType.GetMetaInfo ();
325 if (DeclaringType.IsTypeBuilder) {
326 metaInfo = TypeBuilder.GetField (decl_meta, metaInfo);
328 var orig_token = metaInfo.MetadataToken;
329 metaInfo = decl_meta.GetField (Name, BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static);
330 if (metaInfo.MetadataToken != orig_token)
331 throw new NotImplementedException ("Resolved to wrong meta token");
333 // What a stupid API, does not work because field handle is imported
334 // metaInfo = FieldInfo.GetFieldFromHandle (metaInfo.FieldHandle, DeclaringType.MetaInfo.TypeHandle);
337 state &= ~StateFlags.PendingMetaInflate;
343 public override MemberSpec InflateMember (TypeParameterInflator inflator)
345 var fs = (FieldSpec) base.InflateMember (inflator);
346 fs.memberType = inflator.Inflate (memberType);
350 public FieldSpec Mutate (TypeParameterMutator mutator)
352 var decl = DeclaringType;
353 if (DeclaringType.IsGenericOrParentIsGeneric)
354 decl = mutator.Mutate (decl);
356 if (decl == DeclaringType)
359 var fs = (FieldSpec) MemberwiseClone ();
360 fs.declaringType = decl;
361 fs.state |= StateFlags.PendingMetaInflate;
363 // Gets back FieldInfo in case of metaInfo was inflated
364 fs.metaInfo = MemberCache.GetMember (TypeParameterMutator.GetMemberDeclaringType (DeclaringType), this).metaInfo;
368 public override List<MissingTypeSpecReference> ResolveMissingDependencies (MemberSpec caller)
370 return memberType.ResolveMissingDependencies (this);
375 /// Fixed buffer implementation
377 public class FixedField : FieldBase
379 public const string FixedElementName = "FixedElementField";
380 static int GlobalCounter;
382 TypeBuilder fixed_buffer_type;
384 const Modifiers AllowedModifiers =
387 Modifiers.PROTECTED |
392 public FixedField (TypeDefinition parent, FullNamedExpression type, Modifiers mod, MemberName name, Attributes attrs)
393 : base (parent, type, mod, AllowedModifiers, name, attrs)
400 // Explicit struct layout set by parent
402 public CharSet? CharSetValue {
408 public override Constant ConvertInitializer (ResolveContext rc, Constant expr)
410 return expr.ImplicitConversionRequired (rc, rc.BuiltinTypes.Int);
413 public override bool Define ()
418 if (!BuiltinTypeSpec.IsPrimitiveType (MemberType)) {
419 Report.Error (1663, Location,
420 "`{0}': Fixed size buffers type must be one of the following: bool, byte, short, int, long, char, sbyte, ushort, uint, ulong, float or double",
421 GetSignatureForError ());
422 } else if (declarators != null) {
423 foreach (var d in declarators) {
424 var f = new FixedField (Parent, d.GetFieldTypeExpression (this), ModFlags, new MemberName (d.Name.Value, d.Name.Location), OptAttributes);
425 f.initializer = d.Initializer;
426 ((ConstInitializer) f.initializer).Name = d.Name.Value;
428 Parent.PartialContainer.Members.Add (f);
432 // Create nested fixed buffer container
433 string name = String.Format ("<{0}>__FixedBuffer{1}", TypeDefinition.FilterNestedName (Name), GlobalCounter++);
434 fixed_buffer_type = Parent.TypeBuilder.DefineNestedType (name,
435 TypeAttributes.NestedPublic | TypeAttributes.Sealed | TypeAttributes.BeforeFieldInit,
436 Compiler.BuiltinTypes.ValueType.GetMetaInfo ());
438 var ffield = fixed_buffer_type.DefineField (FixedElementName, MemberType.GetMetaInfo (), FieldAttributes.Public);
440 FieldBuilder = Parent.TypeBuilder.DefineField (Name, fixed_buffer_type, ModifiersExtensions.FieldAttr (ModFlags));
442 var element_spec = new FieldSpec (null, this, MemberType, ffield, ModFlags);
443 spec = new FixedFieldSpec (Module, Parent.Definition, this, FieldBuilder, element_spec, ModFlags);
445 Parent.MemberCache.AddMember (spec);
449 protected override void DoMemberTypeIndependentChecks ()
451 base.DoMemberTypeIndependentChecks ();
454 Expression.UnsafeError (Report, Location);
456 if (Parent.PartialContainer.Kind != MemberKind.Struct) {
457 Report.Error (1642, Location, "`{0}': Fixed size buffer fields may only be members of structs",
458 GetSignatureForError ());
462 public override void Emit()
464 ResolveContext rc = new ResolveContext (this);
465 IntConstant buffer_size_const = initializer.Resolve (rc) as IntConstant;
466 if (buffer_size_const == null)
469 int buffer_size = buffer_size_const.Value;
471 if (buffer_size <= 0) {
472 Report.Error (1665, Location, "`{0}': Fixed size buffers must have a length greater than zero", GetSignatureForError ());
476 EmitFieldSize (buffer_size);
479 if (Module.HasDefaultCharSet)
480 fixed_buffer_type.__SetAttributes (fixed_buffer_type.Attributes | Module.DefaultCharSetType);
483 Module.PredefinedAttributes.UnsafeValueType.EmitAttribute (fixed_buffer_type);
484 Module.PredefinedAttributes.CompilerGenerated.EmitAttribute (fixed_buffer_type);
485 fixed_buffer_type.CreateType ();
490 void EmitFieldSize (int buffer_size)
492 int type_size = BuiltinTypeSpec.GetSize (MemberType);
494 if (buffer_size > int.MaxValue / type_size) {
495 Report.Error (1664, Location, "Fixed size buffer `{0}' of length `{1}' and type `{2}' exceeded 2^31 limit",
496 GetSignatureForError (), buffer_size.ToString (), MemberType.GetSignatureForError ());
500 AttributeEncoder encoder;
503 var char_set = CharSetValue ?? Module.DefaultCharSet ?? 0;
506 // Set struct layout without resolving StructLayoutAttribute which is not always available
509 TypeAttributes attribs = TypeAttributes.SequentialLayout;
513 attribs |= TypeAttributes.AnsiClass;
516 attribs |= TypeAttributes.AutoClass;
518 case CharSet.Unicode:
519 attribs |= TypeAttributes.UnicodeClass;
523 fixed_buffer_type.__SetAttributes (fixed_buffer_type.Attributes | attribs);
524 fixed_buffer_type.__SetLayout (0, buffer_size * type_size);
526 ctor = Module.PredefinedMembers.StructLayoutAttributeCtor.Resolve (Location);
530 var field_size = Module.PredefinedMembers.StructLayoutSize.Resolve (Location);
531 var field_charset = Module.PredefinedMembers.StructLayoutCharSet.Resolve (Location);
532 if (field_size == null || field_charset == null)
535 encoder = new AttributeEncoder ();
536 encoder.Encode ((short)LayoutKind.Sequential);
537 encoder.EncodeNamedArguments (
538 new [] { field_size, field_charset },
540 new IntConstant (Compiler.BuiltinTypes, buffer_size * type_size, Location),
541 new IntConstant (Compiler.BuiltinTypes, (int) char_set, Location)
545 fixed_buffer_type.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), encoder.ToArray ());
548 // Don't emit FixedBufferAttribute attribute for private types
550 if ((ModFlags & Modifiers.PRIVATE) != 0)
553 ctor = Module.PredefinedMembers.FixedBufferAttributeCtor.Resolve (Location);
557 encoder = new AttributeEncoder ();
558 encoder.EncodeTypeName (MemberType);
559 encoder.Encode (buffer_size);
560 encoder.EncodeEmptyNamedArguments ();
562 FieldBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), encoder.ToArray ());
566 class FixedFieldSpec : FieldSpec
568 readonly FieldSpec element;
570 public FixedFieldSpec (ModuleContainer module, TypeSpec declaringType, IMemberDefinition definition, FieldInfo info, FieldSpec element, Modifiers modifiers)
571 : base (declaringType, definition, PointerContainer.MakeType (module, element.MemberType), info, modifiers)
573 this.element = element;
575 // It's never CLS-Compliant
576 state &= ~StateFlags.CLSCompliant_Undetected;
579 public FieldSpec Element {
585 public TypeSpec ElementType {
587 return element.MemberType;
593 // The Field class is used to represents class/struct fields during parsing.
595 public class Field : FieldBase {
597 // Modifiers allowed in a class declaration
599 const Modifiers AllowedModifiers =
602 Modifiers.PROTECTED |
610 public Field (TypeDefinition parent, FullNamedExpression type, Modifiers mod, MemberName name, Attributes attrs)
611 : base (parent, type, mod, AllowedModifiers, name, attrs)
615 bool CanBeVolatile ()
617 switch (MemberType.BuiltinType) {
618 case BuiltinTypeSpec.Type.Bool:
619 case BuiltinTypeSpec.Type.Char:
620 case BuiltinTypeSpec.Type.SByte:
621 case BuiltinTypeSpec.Type.Byte:
622 case BuiltinTypeSpec.Type.Short:
623 case BuiltinTypeSpec.Type.UShort:
624 case BuiltinTypeSpec.Type.Int:
625 case BuiltinTypeSpec.Type.UInt:
626 case BuiltinTypeSpec.Type.Float:
627 case BuiltinTypeSpec.Type.UIntPtr:
628 case BuiltinTypeSpec.Type.IntPtr:
632 if (TypeSpec.IsReferenceType (MemberType))
635 if (MemberType.IsPointer)
638 if (MemberType.IsEnum) {
639 switch (EnumSpec.GetUnderlyingType (MemberType).BuiltinType) {
640 case BuiltinTypeSpec.Type.SByte:
641 case BuiltinTypeSpec.Type.Byte:
642 case BuiltinTypeSpec.Type.Short:
643 case BuiltinTypeSpec.Type.UShort:
644 case BuiltinTypeSpec.Type.Int:
645 case BuiltinTypeSpec.Type.UInt:
655 public override void Accept (StructuralVisitor visitor)
657 visitor.Visit (this);
660 public override bool Define ()
665 MetaType[] required_modifier = null;
666 if ((ModFlags & Modifiers.VOLATILE) != 0) {
667 var mod = Module.PredefinedTypes.IsVolatile.Resolve ();
669 required_modifier = new MetaType[] { mod.GetMetaInfo () };
672 FieldBuilder = Parent.TypeBuilder.DefineField (
673 Name, member_type.GetMetaInfo (), required_modifier, null, ModifiersExtensions.FieldAttr (ModFlags));
675 spec = new FieldSpec (Parent.Definition, this, MemberType, FieldBuilder, ModFlags);
678 // Don't cache inaccessible fields except for struct where we
679 // need them for definitive assignment checks
681 if ((ModFlags & Modifiers.BACKING_FIELD) == 0 || Parent.Kind == MemberKind.Struct) {
682 Parent.MemberCache.AddMember (spec);
685 if (initializer != null) {
686 Parent.RegisterFieldForInitialization (this, new FieldInitializer (this, initializer, TypeExpression.Location));
689 if (declarators != null) {
690 foreach (var d in declarators) {
691 var f = new Field (Parent, d.GetFieldTypeExpression (this), ModFlags, new MemberName (d.Name.Value, d.Name.Location), OptAttributes);
692 if (d.Initializer != null)
693 f.initializer = d.Initializer;
696 Parent.PartialContainer.Members.Add (f);
703 protected override void DoMemberTypeIndependentChecks ()
705 if ((Parent.PartialContainer.ModFlags & Modifiers.READONLY) != 0 && (ModFlags & (Modifiers.READONLY | Modifiers.STATIC)) == 0) {
706 Report.Error (8340, Location, "`{0}': Instance fields in readonly structs must be readonly",
707 GetSignatureForError ());
710 base.DoMemberTypeIndependentChecks ();
713 protected override void DoMemberTypeDependentChecks ()
715 if ((ModFlags & Modifiers.BACKING_FIELD) != 0)
718 base.DoMemberTypeDependentChecks ();
720 if ((ModFlags & Modifiers.VOLATILE) != 0) {
721 if (!CanBeVolatile ()) {
722 Report.Error (677, Location, "`{0}': A volatile field cannot be of the type `{1}'",
723 GetSignatureForError (), MemberType.GetSignatureForError ());
726 if ((ModFlags & Modifiers.READONLY) != 0) {
727 Report.Error (678, Location, "`{0}': A field cannot be both volatile and readonly",
728 GetSignatureForError ());
733 protected override bool VerifyClsCompliance ()
735 if (!base.VerifyClsCompliance ())
738 if ((ModFlags & Modifiers.VOLATILE) != 0) {
739 Report.Warning (3026, 1, Location, "CLS-compliant field `{0}' cannot be volatile", GetSignatureForError ());
746 class PrimaryConstructorField : Field
749 // Proxy resolved parameter type expression to avoid type double resolve
750 // and problems with correct resolve context on partial classes
752 sealed class TypeExpressionFromParameter : TypeExpr
756 public TypeExpressionFromParameter (Parameter parameter)
758 this.parameter = parameter;
759 eclass = ExprClass.Type;
760 loc = parameter.Location;
763 public override TypeSpec ResolveAsType (IMemberContext mc, bool allowUnboundTypeArguments)
765 return parameter.Type;
769 public PrimaryConstructorField (TypeDefinition parent, Parameter parameter)
770 : base (parent, new TypeExpressionFromParameter (parameter), Modifiers.PRIVATE, new MemberName (parameter.Name, parameter.Location), null)
772 caching_flags |= Flags.IsUsed | Flags.IsAssigned;
775 public override string GetSignatureForError ()
777 return MemberName.Name;