private bool UsesIsNullable(TypeSymbol type, ConsList <TypeParameterSymbol> inProgress)
{
if (type is null)
{
return(false);
}
switch (type.TypeKind)
{
case TypeKind.Class:
case TypeKind.Delegate:
case TypeKind.Interface:
case TypeKind.Struct:
case TypeKind.Enum:
if (UsesIsNullable(type.ContainingType, inProgress))
{
return(true);
}
break;
}
switch (type.TypeKind)
{
case TypeKind.Array:
return(UsesIsNullable(((ArrayTypeSymbol)type).ElementType, inProgress));
case TypeKind.Class:
case TypeKind.Delegate:
case TypeKind.Error:
case TypeKind.Interface:
case TypeKind.Struct:
return(UsesIsNullable(((NamedTypeSymbol)type).TypeArgumentsNoUseSiteDiagnostics, inProgress));
case TypeKind.Dynamic:
case TypeKind.Enum:
return(false);
case TypeKind.Pointer:
return(UsesIsNullable(((PointerTypeSymbol)type).PointedAtType, inProgress));
case TypeKind.TypeParameter:
var typeParameter = (TypeParameterSymbol)type;
if (inProgress?.ContainsReference(typeParameter) == true)
{
return(false);
}
inProgress = inProgress ?? ConsList <TypeParameterSymbol> .Empty;
inProgress = inProgress.Prepend(typeParameter);
return(UsesIsNullable(typeParameter.ConstraintTypesNoUseSiteDiagnostics, inProgress) ||
typeParameter.ReferenceTypeConstraintIsNullable == true);
default:
throw ExceptionUtilities.UnexpectedValue(type.TypeKind);
}
}
private bool CheckStruct(ConsList<NamedTypeSymbol> typesWithMembersOfThisType, NamedTypeSymbol nts)
{
// Break recursive cycles. If we find a member that contains us, it is considered empty
if (!typesWithMembersOfThisType.ContainsReference(nts))
{
// Remember that we're in the process of doing this type while checking members.
typesWithMembersOfThisType = new ConsList<NamedTypeSymbol>(nts, typesWithMembersOfThisType);
return CheckStructInstanceFields(typesWithMembersOfThisType, nts);
}
return true;
}
internal override TypeSymbol GetFieldType(ConsList<FieldSymbol> fieldsBeingBound)
{
Debug.Assert(fieldsBeingBound != null);
if ((object)_lazyType != null)
{
return _lazyType;
}
var typeSyntax = TypeSyntax;
var compilation = this.DeclaringCompilation;
var diagnostics = DiagnosticBag.GetInstance();
TypeSymbol type;
var binderFactory = compilation.GetBinderFactory(SyntaxTree);
var binder = binderFactory.GetBinder(typeSyntax);
bool isVar;
type = binder.BindType(typeSyntax, diagnostics, out isVar);
Debug.Assert((object)type != null || isVar);
if (isVar && !fieldsBeingBound.ContainsReference(this))
{
InferFieldType(fieldsBeingBound, binder);
Debug.Assert((object)_lazyType != null);
}
else
{
if (isVar)
{
diagnostics.Add(ErrorCode.ERR_RecursivelyTypedVariable, this.ErrorLocation, this);
type = binder.CreateErrorType("var");
}
SetType(compilation, diagnostics, type);
}
diagnostics.Free();
return _lazyType;
}
/// <summary>
/// Gets the set of interfaces that this type directly implements. This set does not include
/// interfaces that are base interfaces of directly implemented interfaces.
/// </summary>
internal sealed override ImmutableArray<NamedTypeSymbol> InterfacesNoUseSiteDiagnostics(ConsList<Symbol> basesBeingResolved)
{
if (_lazyInterfaces.IsDefault)
{
if (basesBeingResolved != null && basesBeingResolved.ContainsReference(this.OriginalDefinition))
{
return ImmutableArray<NamedTypeSymbol>.Empty;
}
var diagnostics = DiagnosticBag.GetInstance();
var acyclicInterfaces = MakeAcyclicInterfaces(basesBeingResolved, diagnostics);
if (ImmutableInterlocked.InterlockedCompareExchange(ref _lazyInterfaces, acyclicInterfaces, default(ImmutableArray<NamedTypeSymbol>)).IsDefault)
{
AddDeclarationDiagnostics(diagnostics);
}
diagnostics.Free();
}
return _lazyInterfaces;
}
private TypeParameterBounds GetBounds(ConsList<TypeParameterSymbol> inProgress)
{
Debug.Assert(!inProgress.ContainsReference(this));
Debug.Assert(!inProgress.Any() || ReferenceEquals(inProgress.Head.ContainingSymbol, this.ContainingSymbol));
if (ReferenceEquals(_lazyBounds, TypeParameterBounds.Unset))
{
var diagnostics = DiagnosticBag.GetInstance();
var bounds = this.ResolveBounds(inProgress, diagnostics);
if (ReferenceEquals(Interlocked.CompareExchange(ref _lazyBounds, bounds, TypeParameterBounds.Unset), TypeParameterBounds.Unset))
{
this.CheckConstraintTypeConstraints(diagnostics);
this.AddDeclarationDiagnostics(diagnostics);
_state.NotePartComplete(CompletionPart.TypeParameterConstraints);
}
diagnostics.Free();
}
return _lazyBounds;
}
private static TypeSymbol GetNextDeclaredBase(NamedTypeSymbol type, ConsList<Symbol> basesBeingResolved, CSharpCompilation compilation, ref PooledHashSet<NamedTypeSymbol> visited)
{
// We shouldn't have visited this type earlier.
Debug.Assert(visited == null || !visited.Contains(type.OriginalDefinition));
if (basesBeingResolved != null && basesBeingResolved.ContainsReference(type.OriginalDefinition))
{
return null;
}
if (type.SpecialType == SpecialType.System_Object)
{
type.SetKnownToHaveNoDeclaredBaseCycles();
return null;
}
var nextType = type.GetDeclaredBaseType(basesBeingResolved);
// types with no declared bases inherit object's members
if ((object)nextType == null)
{
SetKnownToHaveNoDeclaredBaseCycles(ref visited);
return GetDefaultBaseOrNull(type, compilation);
}
var origType = type.OriginalDefinition;
if (nextType.KnownToHaveNoDeclaredBaseCycles)
{
origType.SetKnownToHaveNoDeclaredBaseCycles();
SetKnownToHaveNoDeclaredBaseCycles(ref visited);
}
else
{
// start cycle tracking
visited = visited ?? PooledHashSet<NamedTypeSymbol>.GetInstance();
visited.Add(origType);
if (visited.Contains(nextType.OriginalDefinition))
{
return GetDefaultBaseOrNull(type, compilation);
}
}
return nextType;
}
private Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> > MakeDeclaredBases(ConsList <TypeSymbol> basesBeingResolved, DiagnosticBag diagnostics)
{
if (this.TypeKind == TypeKind.Enum)
{
// Handled by GetEnumUnderlyingType().
return(new Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> >(null, ImmutableArray <NamedTypeSymbol> .Empty));
}
var reportedPartialConflict = false;
Debug.Assert(basesBeingResolved == null || !basesBeingResolved.ContainsReference(this.OriginalDefinition));
var newBasesBeingResolved = basesBeingResolved.Prepend(this.OriginalDefinition);
var baseInterfaces = ArrayBuilder <NamedTypeSymbol> .GetInstance();
NamedTypeSymbol baseType = null;
SourceLocation baseTypeLocation = null;
var interfaceLocations = SpecializedSymbolCollections.GetPooledSymbolDictionaryInstance <NamedTypeSymbol, SourceLocation>();
foreach (var decl in this.declaration.Declarations)
{
Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> > one = MakeOneDeclaredBases(newBasesBeingResolved, decl, diagnostics);
if ((object)one == null)
{
continue;
}
var partBase = one.Item1;
var partInterfaces = one.Item2;
if (!reportedPartialConflict)
{
if ((object)baseType == null)
{
baseType = partBase;
baseTypeLocation = decl.NameLocation;
}
else if (baseType.TypeKind == TypeKind.Error && (object)partBase != null)
{
// if the old base was an error symbol, copy it to the interfaces list so it doesn't get lost
partInterfaces = partInterfaces.Add(baseType);
baseType = partBase;
baseTypeLocation = decl.NameLocation;
}
else if ((object)partBase != null && !TypeSymbol.Equals(partBase, baseType, TypeCompareKind.ConsiderEverything2) && partBase.TypeKind != TypeKind.Error)
{
// the parts do not agree
var info = diagnostics.Add(ErrorCode.ERR_PartialMultipleBases, Locations[0], this);
baseType = new ExtendedErrorTypeSymbol(baseType, LookupResultKind.Ambiguous, info);
baseTypeLocation = decl.NameLocation;
reportedPartialConflict = true;
}
}
foreach (var t in partInterfaces)
{
if (!interfaceLocations.ContainsKey(t))
{
baseInterfaces.Add(t);
interfaceLocations.Add(t, decl.NameLocation);
}
}
}
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
if (declaration.Kind == DeclarationKind.Record)
{
var type = DeclaringCompilation.GetWellKnownType(WellKnownType.System_IEquatable_T).Construct(this);
if (baseInterfaces.IndexOf(type, SymbolEqualityComparer.AllIgnoreOptions) < 0)
{
baseInterfaces.Add(type);
type.AddUseSiteDiagnostics(ref useSiteDiagnostics);
}
}
if ((object)baseType != null)
{
Debug.Assert(baseTypeLocation != null);
if (baseType.IsStatic)
{
// '{1}': cannot derive from static class '{0}'
diagnostics.Add(ErrorCode.ERR_StaticBaseClass, baseTypeLocation, baseType, this);
}
if (!this.IsNoMoreVisibleThan(baseType, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base class '{1}' is less accessible than class '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseClass, baseTypeLocation, this, baseType);
}
}
var baseInterfacesRO = baseInterfaces.ToImmutableAndFree();
if (DeclaredAccessibility != Accessibility.Private && IsInterface)
{
foreach (var i in baseInterfacesRO)
{
if (!i.IsAtLeastAsVisibleAs(this, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base interface '{1}' is less accessible than interface '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseInterface, interfaceLocations[i], this, i);
}
}
}
interfaceLocations.Free();
diagnostics.Add(Locations[0], useSiteDiagnostics);
return(new Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> >(baseType, baseInterfacesRO));
}
internal sealed override TypeSymbol GetFieldType(ConsList <FieldSymbol> fieldsBeingBound)
{
Debug.Assert(fieldsBeingBound != null);
if ((object)lazyType != null)
{
return(lazyType);
}
var declarator = VariableDeclaratorNode;
var fieldSyntax = GetFieldDeclaration(declarator);
var typeSyntax = fieldSyntax.Declaration.Type;
var compilation = this.DeclaringCompilation;
var diagnostics = DiagnosticBag.GetInstance();
TypeSymbol type;
// When we have multiple declarators, we report the type diagnostics on only the first.
DiagnosticBag diagnosticsForFirstDeclarator = DiagnosticBag.GetInstance();
Symbol associatedPropertyOrEvent = this.AssociatedSymbol;
if ((object)associatedPropertyOrEvent != null && associatedPropertyOrEvent.Kind == SymbolKind.Event)
{
EventSymbol @event = (EventSymbol)associatedPropertyOrEvent;
if (@event.IsWindowsRuntimeEvent)
{
NamedTypeSymbol tokenTableType = this.DeclaringCompilation.GetWellKnownType(WellKnownType.System_Runtime_InteropServices_WindowsRuntime_EventRegistrationTokenTable_T);
Binder.ReportUseSiteDiagnostics(tokenTableType, diagnosticsForFirstDeclarator, this.Location);
// CONSIDER: Do we want to guard against the possibility that someone has created their own EventRegistrationTokenTable<T>
// type that has additional generic constraints?
type = tokenTableType.Construct(@event.Type);
}
else
{
type = @event.Type;
}
}
else
{
var binderFactory = compilation.GetBinderFactory(SyntaxTree);
var binder = binderFactory.GetBinder(typeSyntax);
binder = binder.WithContainingMemberOrLambda(this);
if (!ContainingType.IsScriptClass)
{
type = binder.BindType(typeSyntax, diagnosticsForFirstDeclarator);
if (IsFixed)
{
type = new PointerTypeSymbol(type);
}
}
else
{
bool isVar;
type = binder.BindType(typeSyntax, diagnostics, out isVar);
Debug.Assert((object)type != null || isVar);
if (isVar)
{
if (this.IsConst)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_ImplicitlyTypedVariableCannotBeConst, typeSyntax.Location);
}
if (fieldsBeingBound.ContainsReference(this))
{
diagnostics.Add(ErrorCode.ERR_RecursivelyTypedVariable, this.Location, this);
type = null;
}
else if (fieldSyntax.Declaration.Variables.Count > 1)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_ImplicitlyTypedVariableMultipleDeclarator, typeSyntax.Location);
}
else
{
fieldsBeingBound = new ConsList <FieldSymbol>(this, fieldsBeingBound);
var initializerBinder = new ImplicitlyTypedFieldBinder(binder, fieldsBeingBound);
var initializerOpt = initializerBinder.BindInferredVariableInitializer(diagnostics, declarator.Initializer, declarator);
if (initializerOpt != null)
{
if ((object)initializerOpt.Type != null && !initializerOpt.Type.IsErrorType())
{
type = initializerOpt.Type;
}
this.lazyFieldTypeInferred = 1;
}
}
if ((object)type == null)
{
type = binder.CreateErrorType("var");
}
}
}
if (IsFixed)
{
if (ContainingType.TypeKind != TypeKind.Struct)
{
diagnostics.Add(ErrorCode.ERR_FixedNotInStruct, Location);
}
if (IsStatic)
{
diagnostics.Add(ErrorCode.ERR_BadMemberFlag, Location, SyntaxFacts.GetText(SyntaxKind.StaticKeyword));
}
if (IsVolatile)
{
diagnostics.Add(ErrorCode.ERR_BadMemberFlag, Location, SyntaxFacts.GetText(SyntaxKind.VolatileKeyword));
}
var elementType = ((PointerTypeSymbol)type).PointedAtType;
int elementSize = elementType.FixedBufferElementSizeInBytes();
if (elementSize == 0)
{
var loc = typeSyntax.Location;
diagnostics.Add(ErrorCode.ERR_IllegalFixedType, loc);
}
if (!binder.InUnsafeRegion)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_UnsafeNeeded, declarator.Location);
}
}
}
// update the lazyType only if it contains value last seen by the current thread:
if ((object)Interlocked.CompareExchange(ref lazyType, type, null) == null)
{
TypeChecks(type, fieldSyntax, declarator, diagnostics);
// CONSIDER: SourceEventFieldSymbol would like to suppress these diagnostics.
compilation.SemanticDiagnostics.AddRange(diagnostics);
bool isFirstDeclarator = fieldSyntax.Declaration.Variables[0] == declarator;
if (isFirstDeclarator)
{
compilation.SemanticDiagnostics.AddRange(diagnosticsForFirstDeclarator);
}
state.NotePartComplete(CompletionPart.Type);
}
diagnostics.Free();
diagnosticsForFirstDeclarator.Free();
return(lazyType);
}
internal sealed override TypeSymbolWithAnnotations GetFieldType(ConsList <FieldSymbol> fieldsBeingBound)
{
Debug.Assert(fieldsBeingBound != null);
if (!_lazyType.IsNull)
{
return(_lazyType.ToType());
}
var declarator = VariableDeclaratorNode;
var fieldSyntax = GetFieldDeclaration(declarator);
var typeSyntax = fieldSyntax.Declaration.Type;
var compilation = this.DeclaringCompilation;
var diagnostics = DiagnosticBag.GetInstance();
TypeSymbolWithAnnotations type;
// When we have multiple declarators, we report the type diagnostics on only the first.
DiagnosticBag diagnosticsForFirstDeclarator = DiagnosticBag.GetInstance();
Symbol associatedPropertyOrEvent = this.AssociatedSymbol;
if ((object)associatedPropertyOrEvent != null && associatedPropertyOrEvent.Kind == SymbolKind.Event)
{
EventSymbol @event = (EventSymbol)associatedPropertyOrEvent;
if (@event.IsWindowsRuntimeEvent)
{
NamedTypeSymbol tokenTableType = this.DeclaringCompilation.GetWellKnownType(WellKnownType.System_Runtime_InteropServices_WindowsRuntime_EventRegistrationTokenTable_T);
Binder.ReportUseSiteDiagnostics(tokenTableType, diagnosticsForFirstDeclarator, this.ErrorLocation);
// CONSIDER: Do we want to guard against the possibility that someone has created their own EventRegistrationTokenTable<T>
// type that has additional generic constraints?
type = TypeSymbolWithAnnotations.Create(tokenTableType.Construct(ImmutableArray.Create(@event.Type)));
}
else
{
type = @event.Type;
}
}
else
{
var binderFactory = compilation.GetBinderFactory(SyntaxTree);
var binder = binderFactory.GetBinder(typeSyntax);
binder = binder.WithAdditionalFlagsAndContainingMemberOrLambda(BinderFlags.SuppressConstraintChecks, this);
if (!ContainingType.IsScriptClass)
{
type = binder.BindType(typeSyntax, diagnosticsForFirstDeclarator);
}
else
{
bool isVar;
type = binder.BindTypeOrVarKeyword(typeSyntax, diagnostics, out isVar);
Debug.Assert(!type.IsNull || isVar);
if (isVar)
{
if (this.IsConst)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_ImplicitlyTypedVariableCannotBeConst, typeSyntax.Location);
}
if (fieldsBeingBound.ContainsReference(this))
{
diagnostics.Add(ErrorCode.ERR_RecursivelyTypedVariable, this.ErrorLocation, this);
type = default;
}
else if (fieldSyntax.Declaration.Variables.Count > 1)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_ImplicitlyTypedVariableMultipleDeclarator, typeSyntax.Location);
}
else if (this.IsConst && this.ContainingType.IsScriptClass)
{
// For const var in script, we won't try to bind the initializer (case below), as it can lead to an unbound recursion
type = default;
}
else
{
fieldsBeingBound = new ConsList <FieldSymbol>(this, fieldsBeingBound);
var initializerBinder = new ImplicitlyTypedFieldBinder(binder, fieldsBeingBound);
var initializerOpt = initializerBinder.BindInferredVariableInitializer(diagnostics, RefKind.None, (EqualsValueClauseSyntax)declarator.Initializer, declarator);
if (initializerOpt != null)
{
if ((object)initializerOpt.Type != null && !initializerOpt.Type.IsErrorType())
{
type = TypeSymbolWithAnnotations.Create(initializerOpt.Type);
}
_lazyFieldTypeInferred = 1;
}
}
if (type.IsNull)
{
type = TypeSymbolWithAnnotations.Create(binder.CreateErrorType("var"));
}
}
}
if (IsFixedSizeBuffer)
{
type = TypeSymbolWithAnnotations.Create(new PointerTypeSymbol(type));
if (ContainingType.TypeKind != TypeKind.Struct)
{
diagnostics.Add(ErrorCode.ERR_FixedNotInStruct, ErrorLocation);
}
var elementType = ((PointerTypeSymbol)type.TypeSymbol).PointedAtType.TypeSymbol;
int elementSize = elementType.FixedBufferElementSizeInBytes();
if (elementSize == 0)
{
var loc = typeSyntax.Location;
diagnostics.Add(ErrorCode.ERR_IllegalFixedType, loc);
}
if (!binder.InUnsafeRegion)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_UnsafeNeeded, declarator.Location);
}
}
}
// update the lazyType only if it contains value last seen by the current thread:
if (_lazyType.InterlockedInitialize(type.WithModifiers(this.RequiredCustomModifiers)))
{
TypeChecks(type.TypeSymbol, diagnostics);
// CONSIDER: SourceEventFieldSymbol would like to suppress these diagnostics.
compilation.DeclarationDiagnostics.AddRange(diagnostics);
bool isFirstDeclarator = fieldSyntax.Declaration.Variables[0] == declarator;
if (isFirstDeclarator)
{
compilation.DeclarationDiagnostics.AddRange(diagnosticsForFirstDeclarator);
}
state.NotePartComplete(CompletionPart.Type);
}
diagnostics.Free();
diagnosticsForFirstDeclarator.Free();
return(_lazyType.ToType());
}
private Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol>, ImmutableArray <NamedTypeSymbol> > MakeDeclaredBases(ConsList <Symbol> basesBeingResolved, DiagnosticBag diagnostics)
{
if (this.TypeKind == TypeKind.Enum)
{
// Handled by GetEnumUnderlyingType().
return(Tuple.Create((NamedTypeSymbol)null, ImmutableArray <NamedTypeSymbol> .Empty, ImmutableArray <NamedTypeSymbol> .Empty));
}
var reportedPartialConflict = false;
Debug.Assert(basesBeingResolved == null || !basesBeingResolved.ContainsReference(this.OriginalDefinition));
var newBasesBeingResolved = basesBeingResolved.Prepend(this.OriginalDefinition);
var baseInterfaces = ArrayBuilder <NamedTypeSymbol> .GetInstance();
var interfaceLocations = PooledDictionary <NamedTypeSymbol, SourceLocation> .GetInstance();
var baseConcepts = ArrayBuilder <NamedTypeSymbol> .GetInstance();
var conceptLocations = PooledDictionary <NamedTypeSymbol, SourceLocation> .GetInstance();
NamedTypeSymbol baseType = null;
SourceLocation baseTypeLocation = null;
foreach (var decl in this.declaration.Declarations)
{
var one = MakeOneDeclaredBases(newBasesBeingResolved, decl, diagnostics);
if (!one.HasValue)
{
continue;
}
(var partBase, var partInterfaces, var partConcepts) = one.Value;
if (!reportedPartialConflict)
{
if ((object)baseType == null)
{
baseType = partBase;
baseTypeLocation = decl.NameLocation;
}
else if (baseType.TypeKind == TypeKind.Error && (object)partBase != null)
{
// if the old base was an error symbol, copy it to the interfaces list so it doesn't get lost
partInterfaces = partInterfaces.Add(baseType);
baseType = partBase;
baseTypeLocation = decl.NameLocation;
}
else if ((object)partBase != null && partBase != baseType && partBase.TypeKind != TypeKind.Error)
{
// the parts do not agree
var info = diagnostics.Add(ErrorCode.ERR_PartialMultipleBases, Locations[0], this);
baseType = new ExtendedErrorTypeSymbol(baseType, LookupResultKind.Ambiguous, info);
baseTypeLocation = decl.NameLocation;
reportedPartialConflict = true;
}
}
foreach (var t in partInterfaces)
{
if (!interfaceLocations.ContainsKey(t))
{
baseInterfaces.Add(t);
interfaceLocations.Add(t, decl.NameLocation);
}
}
foreach (var t in partConcepts)
{
if (!conceptLocations.ContainsKey(t))
{
baseConcepts.Add(t);
conceptLocations.Add(t, decl.NameLocation);
}
}
}
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
if ((object)baseType != null)
{
Debug.Assert(baseTypeLocation != null);
if (baseType.IsStatic)
{
// '{1}': cannot derive from static class '{0}'
diagnostics.Add(ErrorCode.ERR_StaticBaseClass, baseTypeLocation, baseType, this);
}
if (!this.IsNoMoreVisibleThan(baseType, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base class '{1}' is less accessible than class '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseClass, baseTypeLocation, this, baseType);
}
}
var baseInterfacesRO = baseInterfaces.ToImmutableAndFree();
if (DeclaredAccessibility != Accessibility.Private && IsInterface)
{
foreach (var i in baseInterfacesRO)
{
if (!i.IsAtLeastAsVisibleAs(this, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base interface '{1}' is less accessible than interface '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseInterface, interfaceLocations[i], this, i);
}
}
}
interfaceLocations.Free();
conceptLocations.Free();
diagnostics.Add(Locations[0], useSiteDiagnostics);
return(Tuple.Create(baseType, baseInterfacesRO, baseConcepts.ToImmutableAndFree()));
}
private TypeParameterBounds GetBounds(ConsList<TypeParameterSymbol> inProgress)
{
Debug.Assert(!inProgress.ContainsReference(this));
Debug.Assert(!inProgress.Any() || ReferenceEquals(inProgress.Head.ContainingSymbol, this.ContainingSymbol));
if (ReferenceEquals(_lazyBounds, TypeParameterBounds.Unset))
{
var constraintTypes = GetDeclaredConstraintTypes();
Debug.Assert(!constraintTypes.IsDefault);
var diagnostics = ArrayBuilder<TypeParameterDiagnosticInfo>.GetInstance();
ArrayBuilder<TypeParameterDiagnosticInfo> useSiteDiagnosticsBuilder = null;
bool inherited = (_containingSymbol.Kind == SymbolKind.Method) && ((MethodSymbol)_containingSymbol).IsOverride;
var bounds = this.ResolveBounds(this.ContainingAssembly.CorLibrary, inProgress.Prepend(this), constraintTypes, inherited, currentCompilation: null,
diagnosticsBuilder: diagnostics, useSiteDiagnosticsBuilder: ref useSiteDiagnosticsBuilder);
DiagnosticInfo errorInfo = null;
if (diagnostics.Count > 0)
{
errorInfo = diagnostics[0].DiagnosticInfo;
}
else if (useSiteDiagnosticsBuilder != null && useSiteDiagnosticsBuilder.Count > 0)
{
foreach (var diag in useSiteDiagnosticsBuilder)
{
if (diag.DiagnosticInfo.Severity == DiagnosticSeverity.Error)
{
errorInfo = diag.DiagnosticInfo;
break;
}
else if ((object)errorInfo == null)
{
errorInfo = diag.DiagnosticInfo;
}
}
}
diagnostics.Free();
Interlocked.CompareExchange(ref _lazyBoundsErrorInfo, errorInfo, CSDiagnosticInfo.EmptyErrorInfo);
Interlocked.CompareExchange(ref _lazyBounds, bounds, TypeParameterBounds.Unset);
}
Debug.Assert(!ReferenceEquals(_lazyBoundsErrorInfo, CSDiagnosticInfo.EmptyErrorInfo));
return _lazyBounds;
}
// Based on SymbolLoader::ResolveBounds.
public static TypeParameterBounds ResolveBounds(
this TypeParameterSymbol typeParameter,
AssemblySymbol corLibrary,
ConsList <TypeParameterSymbol> inProgress,
ImmutableArray <TypeSymbol> constraintTypes,
bool inherited,
CSharpCompilation currentCompilation,
ArrayBuilder <TypeParameterDiagnosticInfo> diagnosticsBuilder,
ref ArrayBuilder <TypeParameterDiagnosticInfo> useSiteDiagnosticsBuilder)
{
Debug.Assert(currentCompilation == null || typeParameter.IsFromCompilation(currentCompilation));
ImmutableArray <NamedTypeSymbol> interfaces;
NamedTypeSymbol effectiveBaseClass = corLibrary.GetSpecialType(typeParameter.HasValueTypeConstraint ? SpecialType.System_ValueType : SpecialType.System_Object);
TypeSymbol deducedBaseType = effectiveBaseClass;
DynamicTypeEraser dynamicEraser = null;
if (constraintTypes.Length == 0)
{
interfaces = ImmutableArray <NamedTypeSymbol> .Empty;
}
else
{
var constraintTypesBuilder = ArrayBuilder <TypeSymbol> .GetInstance();
var interfacesBuilder = ArrayBuilder <NamedTypeSymbol> .GetInstance();
var conversions = new TypeConversions(corLibrary);
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
// Resolve base types, determine the effective base class and
// interfaces, and filter out any constraint types that cause cycles.
foreach (var constraintType in constraintTypes)
{
NamedTypeSymbol constraintEffectiveBase;
TypeSymbol constraintDeducedBase;
switch (constraintType.TypeKind)
{
case TypeKind.Dynamic:
Debug.Assert(inherited || currentCompilation == null);
continue;
case TypeKind.TypeParameter:
{
var containingSymbol = typeParameter.ContainingSymbol;
var constraintTypeParameter = (TypeParameterSymbol)constraintType;
ConsList <TypeParameterSymbol> constraintsInProgress;
if (constraintTypeParameter.ContainingSymbol == containingSymbol)
{
// The constraint type parameter is from the same containing type or method.
if (inProgress.ContainsReference(constraintTypeParameter))
{
// "Circular constraint dependency involving '{0}' and '{1}'"
diagnosticsBuilder.Add(new TypeParameterDiagnosticInfo(constraintTypeParameter, new CSDiagnosticInfo(ErrorCode.ERR_CircularConstraint, constraintTypeParameter, typeParameter)));
continue;
}
constraintsInProgress = inProgress;
}
else
{
// The constraint type parameter is from a different containing symbol so no cycle.
constraintsInProgress = ConsList <TypeParameterSymbol> .Empty;
}
// Use the calculated bounds from the constraint type parameter.
constraintEffectiveBase = constraintTypeParameter.GetEffectiveBaseClass(constraintsInProgress);
constraintDeducedBase = constraintTypeParameter.GetDeducedBaseType(constraintsInProgress);
AddInterfaces(interfacesBuilder, constraintTypeParameter.GetInterfaces(constraintsInProgress));
if (constraintTypeParameter.HasValueTypeConstraint && !inherited && currentCompilation != null && constraintTypeParameter.IsFromCompilation(currentCompilation))
{
// "Type parameter '{1}' has the 'struct' constraint so '{1}' cannot be used as a constraint for '{0}'"
diagnosticsBuilder.Add(new TypeParameterDiagnosticInfo(typeParameter, new CSDiagnosticInfo(ErrorCode.ERR_ConWithValCon, typeParameter, constraintTypeParameter)));
continue;
}
}
break;
case TypeKind.Interface:
case TypeKind.Class:
case TypeKind.Delegate:
NamedTypeSymbol erasedConstraintType;
if (inherited || currentCompilation == null)
{
// only inherited constraints may contain dynamic
if (dynamicEraser == null)
{
dynamicEraser = new DynamicTypeEraser(corLibrary.GetSpecialType(SpecialType.System_Object));
}
erasedConstraintType = (NamedTypeSymbol)dynamicEraser.EraseDynamic(constraintType);
}
else
{
Debug.Assert(!constraintType.ContainsDynamic());
Debug.Assert(constraintType.TypeKind != TypeKind.Delegate);
erasedConstraintType = (NamedTypeSymbol)constraintType;
}
if (constraintType.IsInterfaceType())
{
AddInterface(interfacesBuilder, erasedConstraintType);
constraintTypesBuilder.Add(constraintType);
continue;
}
else
{
constraintEffectiveBase = erasedConstraintType;
constraintDeducedBase = constraintType;
break;
}
case TypeKind.Struct:
Debug.Assert(inherited || currentCompilation == null);
constraintEffectiveBase = corLibrary.GetSpecialType(SpecialType.System_ValueType);
constraintDeducedBase = constraintType;
break;
case TypeKind.Enum:
Debug.Assert(inherited || currentCompilation == null);
constraintEffectiveBase = corLibrary.GetSpecialType(SpecialType.System_Enum);
constraintDeducedBase = constraintType;
break;
case TypeKind.Array:
Debug.Assert(inherited || currentCompilation == null);
constraintEffectiveBase = corLibrary.GetSpecialType(SpecialType.System_Array);
constraintDeducedBase = constraintType;
break;
case TypeKind.Error:
constraintEffectiveBase = (NamedTypeSymbol)constraintType;
constraintDeducedBase = constraintType;
break;
case TypeKind.Submission:
default:
throw ExceptionUtilities.UnexpectedValue(constraintType.TypeKind);
}
CheckEffectiveAndDeducedBaseTypes(conversions, constraintEffectiveBase, constraintDeducedBase);
constraintTypesBuilder.Add(constraintType);
// Determine the more encompassed of the current effective base
// class and the previously computed effective base class.
if (!deducedBaseType.IsErrorType() && !constraintDeducedBase.IsErrorType())
{
if (!IsEncompassedBy(conversions, deducedBaseType, constraintDeducedBase, ref useSiteDiagnostics))
{
if (!IsEncompassedBy(conversions, constraintDeducedBase, deducedBaseType, ref useSiteDiagnostics))
{
// "Type parameter '{0}' inherits conflicting constraints '{1}' and '{2}'"
diagnosticsBuilder.Add(new TypeParameterDiagnosticInfo(typeParameter, new CSDiagnosticInfo(ErrorCode.ERR_BaseConstraintConflict, typeParameter, constraintDeducedBase, deducedBaseType)));
}
else
{
deducedBaseType = constraintDeducedBase;
effectiveBaseClass = constraintEffectiveBase;
}
}
}
}
AppendUseSiteDiagnostics(useSiteDiagnostics, typeParameter, ref useSiteDiagnosticsBuilder);
CheckEffectiveAndDeducedBaseTypes(conversions, effectiveBaseClass, deducedBaseType);
constraintTypes = constraintTypesBuilder.ToImmutableAndFree();
interfaces = interfacesBuilder.ToImmutableAndFree();
}
Debug.Assert((effectiveBaseClass.SpecialType == SpecialType.System_Object) || (deducedBaseType.SpecialType != SpecialType.System_Object));
// Only create a TypeParameterBounds instance for this type
// parameter if the bounds are not the default values.
if ((constraintTypes.Length == 0) && (deducedBaseType.SpecialType == SpecialType.System_Object))
{
Debug.Assert(effectiveBaseClass.SpecialType == SpecialType.System_Object);
Debug.Assert(interfaces.Length == 0);
return(null);
}
var bounds = new TypeParameterBounds(constraintTypes, interfaces, effectiveBaseClass, deducedBaseType);
// Additional constraint checks for overrides.
if (inherited)
{
CheckOverrideConstraints(typeParameter, bounds, diagnosticsBuilder);
}
return(bounds);
}
private Tuple<NamedTypeSymbol, ImmutableArray<NamedTypeSymbol>> MakeDeclaredBases(ConsList<Symbol> basesBeingResolved, DiagnosticBag diagnostics)
{
if (this.TypeKind == TypeKind.Enum)
{
// Handled by GetEnumUnderlyingType().
return new Tuple<NamedTypeSymbol, ImmutableArray<NamedTypeSymbol>>(null, ImmutableArray<NamedTypeSymbol>.Empty);
}
var reportedPartialConflict = false;
Debug.Assert(basesBeingResolved == null || !basesBeingResolved.ContainsReference(this.OriginalDefinition));
var newBasesBeingResolved = basesBeingResolved.Prepend(this.OriginalDefinition);
var baseInterfaces = ArrayBuilder<NamedTypeSymbol>.GetInstance();
NamedTypeSymbol baseType = null;
foreach (var decl in this.declaration.Declarations)
{
Tuple<NamedTypeSymbol, ImmutableArray<NamedTypeSymbol>> one = MakeOneDeclaredBases(newBasesBeingResolved, decl, diagnostics);
if ((object)one == null) continue;
var partBase = one.Item1;
var partInterfaces = one.Item2;
if (!reportedPartialConflict)
{
if ((object)baseType == null)
{
baseType = partBase;
}
else if (baseType.TypeKind == TypeKind.Error && (object)partBase != null)
{
// if the old base was an error symbol, copy it to the interfaces list so it doesn't get lost
partInterfaces = partInterfaces.Add(baseType);
baseType = partBase;
}
else if ((object)partBase != null && partBase != baseType && partBase.TypeKind != TypeKind.Error)
{
// the parts do not agree
var info = diagnostics.Add(ErrorCode.ERR_PartialMultipleBases, Locations[0], this);
baseType = new ExtendedErrorTypeSymbol(baseType, LookupResultKind.Ambiguous, info);
reportedPartialConflict = true;
}
}
int n = baseInterfaces.Count;
foreach (var t in partInterfaces) // this could probably be done more efficiently with a side hash table if it proves necessary
{
for (int i = 0; i < n; i++)
{
if (t == baseInterfaces[i])
{
goto alreadyInInterfaceList;
}
}
baseInterfaces.Add(t);
alreadyInInterfaceList:;
}
}
if ((object)baseType != null && baseType.IsStatic)
{
// '{1}': cannot derive from static class '{0}'
diagnostics.Add(ErrorCode.ERR_StaticBaseClass, Locations[0], baseType, this);
}
HashSet<DiagnosticInfo> useSiteDiagnostics = null;
if ((object)baseType != null && !this.IsNoMoreVisibleThan(baseType, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base class '{1}' is less accessible than class '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseClass, Locations[0], this, baseType);
}
var baseInterfacesRO = baseInterfaces.ToImmutableAndFree();
if (DeclaredAccessibility != Accessibility.Private && IsInterface)
{
foreach (var i in baseInterfacesRO)
{
if (!i.IsAtLeastAsVisibleAs(this, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base interface '{1}' is less accessible than interface '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseInterface, Locations[0], this, i);
}
}
}
diagnostics.Add(Locations[0], useSiteDiagnostics);
return new Tuple<NamedTypeSymbol, ImmutableArray<NamedTypeSymbol>>(baseType, baseInterfacesRO);
}
private Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> > MakeDeclaredBases(ConsList <TypeSymbol> basesBeingResolved, BindingDiagnosticBag diagnostics)
{
if (this.TypeKind == TypeKind.Enum)
{
// Handled by GetEnumUnderlyingType().
return(new Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> >(null, ImmutableArray <NamedTypeSymbol> .Empty));
}
var reportedPartialConflict = false;
Debug.Assert(basesBeingResolved == null || !basesBeingResolved.ContainsReference(this.OriginalDefinition));
var newBasesBeingResolved = basesBeingResolved.Prepend(this.OriginalDefinition);
var baseInterfaces = ArrayBuilder <NamedTypeSymbol> .GetInstance();
NamedTypeSymbol baseType = null;
SourceLocation baseTypeLocation = null;
var interfaceLocations = SpecializedSymbolCollections.GetPooledSymbolDictionaryInstance <NamedTypeSymbol, SourceLocation>();
foreach (var decl in this.declaration.Declarations)
{
Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> > one = MakeOneDeclaredBases(newBasesBeingResolved, decl, diagnostics);
if ((object)one == null)
{
continue;
}
var partBase = one.Item1;
var partInterfaces = one.Item2;
if (!reportedPartialConflict)
{
if ((object)baseType == null)
{
baseType = partBase;
baseTypeLocation = decl.NameLocation;
}
else if (baseType.TypeKind == TypeKind.Error && (object)partBase != null)
{
// if the old base was an error symbol, copy it to the interfaces list so it doesn't get lost
partInterfaces = partInterfaces.Add(baseType);
baseType = partBase;
baseTypeLocation = decl.NameLocation;
}
else if ((object)partBase != null && !TypeSymbol.Equals(partBase, baseType, TypeCompareKind.ConsiderEverything) && partBase.TypeKind != TypeKind.Error)
{
// the parts do not agree
if (partBase.Equals(baseType, TypeCompareKind.ObliviousNullableModifierMatchesAny))
{
if (containsOnlyOblivious(baseType))
{
baseType = partBase;
baseTypeLocation = decl.NameLocation;
continue;
}
else if (containsOnlyOblivious(partBase))
{
continue;
}
}
var info = diagnostics.Add(ErrorCode.ERR_PartialMultipleBases, Locations[0], this);
baseType = new ExtendedErrorTypeSymbol(baseType, LookupResultKind.Ambiguous, info);
baseTypeLocation = decl.NameLocation;
reportedPartialConflict = true;
private Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> > MakeDeclaredBases(ConsList <Symbol> basesBeingResolved, DiagnosticBag diagnostics)
{
if (this.TypeKind == TypeKind.Enum)
{
// Handled by GetEnumUnderlyingType().
return(new Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> >(null, ImmutableArray <NamedTypeSymbol> .Empty));
}
var reportedPartialConflict = false;
Debug.Assert(basesBeingResolved == null || !basesBeingResolved.ContainsReference(this.OriginalDefinition));
var newBasesBeingResolved = basesBeingResolved.Prepend(this.OriginalDefinition);
var baseInterfaces = ArrayBuilder <NamedTypeSymbol> .GetInstance();
NamedTypeSymbol baseType = null;
foreach (var decl in this.declaration.Declarations)
{
Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> > one = MakeOneDeclaredBases(newBasesBeingResolved, decl, diagnostics);
if ((object)one == null)
{
continue;
}
var partBase = one.Item1;
var partInterfaces = one.Item2;
if (!reportedPartialConflict)
{
if ((object)baseType == null)
{
baseType = partBase;
}
else if (baseType.TypeKind == TypeKind.Error && (object)partBase != null)
{
// if the old base was an error symbol, copy it to the interfaces list so it doesn't get lost
partInterfaces = partInterfaces.Add(baseType);
baseType = partBase;
}
else if ((object)partBase != null && partBase != baseType && partBase.TypeKind != TypeKind.Error)
{
// the parts do not agree
var info = diagnostics.Add(ErrorCode.ERR_PartialMultipleBases, Locations[0], this);
baseType = new ExtendedErrorTypeSymbol(baseType, LookupResultKind.Ambiguous, info);
reportedPartialConflict = true;
}
}
int n = baseInterfaces.Count;
foreach (var t in partInterfaces) // this could probably be done more efficiently with a side hash table if it proves necessary
{
for (int i = 0; i < n; i++)
{
if (t == baseInterfaces[i])
{
goto alreadyInInterfaceList;
}
}
baseInterfaces.Add(t);
alreadyInInterfaceList :;
}
}
if ((object)baseType != null && baseType.IsStatic)
{
// '{1}': cannot derive from static class '{0}'
diagnostics.Add(ErrorCode.ERR_StaticBaseClass, Locations[0], baseType, this);
}
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
if ((object)baseType != null && !this.IsNoMoreVisibleThan(baseType, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base class '{1}' is less accessible than class '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseClass, Locations[0], this, baseType);
}
var baseInterfacesRO = baseInterfaces.ToImmutableAndFree();
if (DeclaredAccessibility != Accessibility.Private && IsInterface)
{
foreach (var i in baseInterfacesRO)
{
if (!i.IsAtLeastAsVisibleAs(this, ref useSiteDiagnostics))
{
// Inconsistent accessibility: base interface '{1}' is less accessible than interface '{0}'
diagnostics.Add(ErrorCode.ERR_BadVisBaseInterface, Locations[0], this, i);
}
}
}
diagnostics.Add(Locations[0], useSiteDiagnostics);
return(new Tuple <NamedTypeSymbol, ImmutableArray <NamedTypeSymbol> >(baseType, baseInterfacesRO));
}
// Based on SymbolLoader::ResolveBounds.
public static TypeParameterBounds ResolveBounds(
this TypeParameterSymbol typeParameter,
AssemblySymbol corLibrary,
ConsList<TypeParameterSymbol> inProgress,
ImmutableArray<TypeSymbol> constraintTypes,
bool inherited,
CSharpCompilation currentCompilation,
ArrayBuilder<TypeParameterDiagnosticInfo> diagnosticsBuilder,
ref ArrayBuilder<TypeParameterDiagnosticInfo> useSiteDiagnosticsBuilder)
{
Debug.Assert(currentCompilation == null || typeParameter.IsFromCompilation(currentCompilation));
ImmutableArray<NamedTypeSymbol> interfaces;
NamedTypeSymbol effectiveBaseClass = corLibrary.GetSpecialType(typeParameter.HasValueTypeConstraint ? SpecialType.System_ValueType : SpecialType.System_Object);
TypeSymbol deducedBaseType = effectiveBaseClass;
DynamicTypeEraser dynamicEraser = null;
if (constraintTypes.Length == 0)
{
interfaces = ImmutableArray<NamedTypeSymbol>.Empty;
}
else
{
var constraintTypesBuilder = ArrayBuilder<TypeSymbol>.GetInstance();
var interfacesBuilder = ArrayBuilder<NamedTypeSymbol>.GetInstance();
var conversions = new TypeConversions(corLibrary);
HashSet<DiagnosticInfo> useSiteDiagnostics = null;
// Resolve base types, determine the effective base class and
// interfaces, and filter out any constraint types that cause cycles.
foreach (var constraintType in constraintTypes)
{
NamedTypeSymbol constraintEffectiveBase;
TypeSymbol constraintDeducedBase;
switch (constraintType.TypeKind)
{
case TypeKind.Dynamic:
Debug.Assert(inherited || currentCompilation == null);
continue;
case TypeKind.TypeParameter:
{
var containingSymbol = typeParameter.ContainingSymbol;
var constraintTypeParameter = (TypeParameterSymbol)constraintType;
ConsList<TypeParameterSymbol> constraintsInProgress;
if (constraintTypeParameter.ContainingSymbol == containingSymbol)
{
// The constraint type parameter is from the same containing type or method.
if (inProgress.ContainsReference(constraintTypeParameter))
{
// "Circular constraint dependency involving '{0}' and '{1}'"
diagnosticsBuilder.Add(new TypeParameterDiagnosticInfo(constraintTypeParameter, new CSDiagnosticInfo(ErrorCode.ERR_CircularConstraint, constraintTypeParameter, typeParameter)));
continue;
}
constraintsInProgress = inProgress;
}
else
{
// The constraint type parameter is from a different containing symbol so no cycle.
constraintsInProgress = ConsList<TypeParameterSymbol>.Empty;
}
// Use the calculated bounds from the constraint type parameter.
constraintEffectiveBase = constraintTypeParameter.GetEffectiveBaseClass(constraintsInProgress);
constraintDeducedBase = constraintTypeParameter.GetDeducedBaseType(constraintsInProgress);
AddInterfaces(interfacesBuilder, constraintTypeParameter.GetInterfaces(constraintsInProgress));
if (constraintTypeParameter.HasValueTypeConstraint && !inherited && currentCompilation != null && constraintTypeParameter.IsFromCompilation(currentCompilation))
{
// "Type parameter '{1}' has the 'struct' constraint so '{1}' cannot be used as a constraint for '{0}'"
diagnosticsBuilder.Add(new TypeParameterDiagnosticInfo(typeParameter, new CSDiagnosticInfo(ErrorCode.ERR_ConWithValCon, typeParameter, constraintTypeParameter)));
continue;
}
}
break;
case TypeKind.Interface:
case TypeKind.Class:
case TypeKind.Delegate:
NamedTypeSymbol erasedConstraintType;
if (inherited || currentCompilation == null)
{
// only inherited constraints may contain dynamic
if (dynamicEraser == null)
{
dynamicEraser = new DynamicTypeEraser(corLibrary.GetSpecialType(SpecialType.System_Object));
}
erasedConstraintType = (NamedTypeSymbol)dynamicEraser.EraseDynamic(constraintType);
}
else
{
Debug.Assert(!constraintType.ContainsDynamic());
Debug.Assert(constraintType.TypeKind != TypeKind.Delegate);
erasedConstraintType = (NamedTypeSymbol)constraintType;
}
if (constraintType.IsInterfaceType())
{
AddInterface(interfacesBuilder, erasedConstraintType);
constraintTypesBuilder.Add(constraintType);
continue;
}
else
{
constraintEffectiveBase = erasedConstraintType;
constraintDeducedBase = constraintType;
break;
}
case TypeKind.Struct:
Debug.Assert(inherited || currentCompilation == null);
constraintEffectiveBase = corLibrary.GetSpecialType(SpecialType.System_ValueType);
constraintDeducedBase = constraintType;
break;
case TypeKind.Enum:
Debug.Assert(inherited || currentCompilation == null);
constraintEffectiveBase = corLibrary.GetSpecialType(SpecialType.System_Enum);
constraintDeducedBase = constraintType;
break;
case TypeKind.Array:
Debug.Assert(inherited || currentCompilation == null);
constraintEffectiveBase = corLibrary.GetSpecialType(SpecialType.System_Array);
constraintDeducedBase = constraintType;
break;
case TypeKind.Error:
constraintEffectiveBase = (NamedTypeSymbol)constraintType;
constraintDeducedBase = constraintType;
break;
case TypeKind.Submission:
default:
throw ExceptionUtilities.UnexpectedValue(constraintType.TypeKind);
}
CheckEffectiveAndDeducedBaseTypes(conversions, constraintEffectiveBase, constraintDeducedBase);
constraintTypesBuilder.Add(constraintType);
// Determine the more encompassed of the current effective base
// class and the previously computed effective base class.
if (!deducedBaseType.IsErrorType() && !constraintDeducedBase.IsErrorType())
{
if (!IsEncompassedBy(conversions, deducedBaseType, constraintDeducedBase, ref useSiteDiagnostics))
{
if (!IsEncompassedBy(conversions, constraintDeducedBase, deducedBaseType, ref useSiteDiagnostics))
{
// "Type parameter '{0}' inherits conflicting constraints '{1}' and '{2}'"
diagnosticsBuilder.Add(new TypeParameterDiagnosticInfo(typeParameter, new CSDiagnosticInfo(ErrorCode.ERR_BaseConstraintConflict, typeParameter, constraintDeducedBase, deducedBaseType)));
}
else
{
deducedBaseType = constraintDeducedBase;
effectiveBaseClass = constraintEffectiveBase;
}
}
}
}
AppendUseSiteDiagnostics(useSiteDiagnostics, typeParameter, ref useSiteDiagnosticsBuilder);
CheckEffectiveAndDeducedBaseTypes(conversions, effectiveBaseClass, deducedBaseType);
constraintTypes = constraintTypesBuilder.ToImmutableAndFree();
interfaces = interfacesBuilder.ToImmutableAndFree();
}
Debug.Assert((effectiveBaseClass.SpecialType == SpecialType.System_Object) || (deducedBaseType.SpecialType != SpecialType.System_Object));
// Only create a TypeParameterBounds instance for this type
// parameter if the bounds are not the default values.
if ((constraintTypes.Length == 0) && (deducedBaseType.SpecialType == SpecialType.System_Object))
{
Debug.Assert(effectiveBaseClass.SpecialType == SpecialType.System_Object);
Debug.Assert(interfaces.Length == 0);
return null;
}
var bounds = new TypeParameterBounds(constraintTypes, interfaces, effectiveBaseClass, deducedBaseType);
// Additional constraint checks for overrides.
if (inherited)
{
CheckOverrideConstraints(typeParameter, bounds, diagnosticsBuilder);
}
return bounds;
}
internal sealed override TypeSymbol GetFieldType(ConsList<FieldSymbol> fieldsBeingBound)
{
Debug.Assert(fieldsBeingBound != null);
if ((object)_lazyType != null)
{
return _lazyType;
}
var declarator = VariableDeclaratorNode;
var fieldSyntax = GetFieldDeclaration(declarator);
var typeSyntax = fieldSyntax.Declaration.Type;
var compilation = this.DeclaringCompilation;
var diagnostics = DiagnosticBag.GetInstance();
TypeSymbol type;
// When we have multiple declarators, we report the type diagnostics on only the first.
DiagnosticBag diagnosticsForFirstDeclarator = DiagnosticBag.GetInstance();
Symbol associatedPropertyOrEvent = this.AssociatedSymbol;
if ((object)associatedPropertyOrEvent != null && associatedPropertyOrEvent.Kind == SymbolKind.Event)
{
EventSymbol @event = (EventSymbol)associatedPropertyOrEvent;
if (@event.IsWindowsRuntimeEvent)
{
NamedTypeSymbol tokenTableType = this.DeclaringCompilation.GetWellKnownType(WellKnownType.System_Runtime_InteropServices_WindowsRuntime_EventRegistrationTokenTable_T);
Binder.ReportUseSiteDiagnostics(tokenTableType, diagnosticsForFirstDeclarator, this.ErrorLocation);
// CONSIDER: Do we want to guard against the possibility that someone has created their own EventRegistrationTokenTable<T>
// type that has additional generic constraints?
type = tokenTableType.Construct(@event.Type);
}
else
{
type = @event.Type;
}
}
else
{
var binderFactory = compilation.GetBinderFactory(SyntaxTree);
var binder = binderFactory.GetBinder(typeSyntax);
binder = binder.WithContainingMemberOrLambda(this);
if (!ContainingType.IsScriptClass)
{
type = binder.BindType(typeSyntax, diagnosticsForFirstDeclarator);
if (IsFixed)
{
type = new PointerTypeSymbol(type);
}
}
else
{
bool isVar;
type = binder.BindType(typeSyntax, diagnostics, out isVar);
Debug.Assert((object)type != null || isVar);
if (isVar)
{
if (this.IsConst)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_ImplicitlyTypedVariableCannotBeConst, typeSyntax.Location);
}
if (fieldsBeingBound.ContainsReference(this))
{
diagnostics.Add(ErrorCode.ERR_RecursivelyTypedVariable, this.ErrorLocation, this);
type = null;
}
else if (fieldSyntax.Declaration.Variables.Count > 1)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_ImplicitlyTypedVariableMultipleDeclarator, typeSyntax.Location);
}
else
{
fieldsBeingBound = new ConsList<FieldSymbol>(this, fieldsBeingBound);
var initializerBinder = new ImplicitlyTypedFieldBinder(binder, fieldsBeingBound);
var initializerOpt = initializerBinder.BindInferredVariableInitializer(diagnostics, declarator.Initializer, declarator);
if (initializerOpt != null)
{
if ((object)initializerOpt.Type != null && !initializerOpt.Type.IsErrorType())
{
type = initializerOpt.Type;
}
_lazyFieldTypeInferred = 1;
}
}
if ((object)type == null)
{
type = binder.CreateErrorType("var");
}
}
}
if (IsFixed)
{
if (ContainingType.TypeKind != TypeKind.Struct)
{
diagnostics.Add(ErrorCode.ERR_FixedNotInStruct, ErrorLocation);
}
var elementType = ((PointerTypeSymbol)type).PointedAtType;
int elementSize = elementType.FixedBufferElementSizeInBytes();
if (elementSize == 0)
{
var loc = typeSyntax.Location;
diagnostics.Add(ErrorCode.ERR_IllegalFixedType, loc);
}
if (!binder.InUnsafeRegion)
{
diagnosticsForFirstDeclarator.Add(ErrorCode.ERR_UnsafeNeeded, declarator.Location);
}
}
}
// update the lazyType only if it contains value last seen by the current thread:
if ((object)Interlocked.CompareExchange(ref _lazyType, type, null) == null)
{
TypeChecks(type, fieldSyntax, declarator, diagnostics);
// CONSIDER: SourceEventFieldSymbol would like to suppress these diagnostics.
compilation.DeclarationDiagnostics.AddRange(diagnostics);
bool isFirstDeclarator = fieldSyntax.Declaration.Variables[0] == declarator;
if (isFirstDeclarator)
{
compilation.DeclarationDiagnostics.AddRange(diagnosticsForFirstDeclarator);
}
state.NotePartComplete(CompletionPart.Type);
}
diagnostics.Free();
diagnosticsForFirstDeclarator.Free();
return _lazyType;
}
private ImmutableArray <TypeWithAnnotations> GetDeclaredConstraintTypes(ConsList <PETypeParameterSymbol> inProgress)
{
Debug.Assert(!inProgress.ContainsReference(this));
Debug.Assert(!inProgress.Any() || ReferenceEquals(inProgress.Head.ContainingSymbol, this.ContainingSymbol));
if (_lazyDeclaredConstraintTypes.IsDefault)
{
ImmutableArray <TypeWithAnnotations> declaredConstraintTypes;
var moduleSymbol = ((PEModuleSymbol)this.ContainingModule);
PEModule peModule = moduleSymbol.Module;
GenericParameterConstraintHandleCollection constraints = GetConstraintHandleCollection(peModule);
bool hasUnmanagedModreqPattern = false;
if (constraints.Count > 0)
{
var symbolsBuilder = ArrayBuilder <TypeWithAnnotations> .GetInstance();
MetadataDecoder tokenDecoder = GetDecoderForConstraintTypes(moduleSymbol);
TypeWithAnnotations bestObjectConstraint = default;
var metadataReader = peModule.MetadataReader;
foreach (var constraintHandle in constraints)
{
TypeWithAnnotations type = GetConstraintTypeOrDefault(moduleSymbol, metadataReader, tokenDecoder, constraintHandle, ref hasUnmanagedModreqPattern);
if (!type.HasType)
{
// Dropped 'System.ValueType' constraint type when the 'valuetype' constraint was also specified.
continue;
}
// Drop 'System.Object' constraint type.
if (ConstraintsHelper.IsObjectConstraint(type, ref bestObjectConstraint))
{
continue;
}
symbolsBuilder.Add(type);
}
if (bestObjectConstraint.HasType)
{
// See if we need to put Object! or Object~ back in order to preserve nullability information for the type parameter.
if (ConstraintsHelper.IsObjectConstraintSignificant(CalculateIsNotNullableFromNonTypeConstraints(), bestObjectConstraint))
{
Debug.Assert(!HasNotNullConstraint && !HasValueTypeConstraint);
if (symbolsBuilder.Count == 0)
{
if (bestObjectConstraint.NullableAnnotation.IsOblivious() && !HasReferenceTypeConstraint)
{
bestObjectConstraint = default;
}
}
else
{
inProgress = inProgress.Prepend(this);
foreach (TypeWithAnnotations constraintType in symbolsBuilder)
{
if (!ConstraintsHelper.IsObjectConstraintSignificant(IsNotNullableFromConstraintType(constraintType, inProgress, out _), bestObjectConstraint))
{
bestObjectConstraint = default;
break;
}
}
}
if (bestObjectConstraint.HasType)
{
symbolsBuilder.Insert(0, bestObjectConstraint);
}
}
}
declaredConstraintTypes = symbolsBuilder.ToImmutableAndFree();
}
else
{
declaredConstraintTypes = ImmutableArray <TypeWithAnnotations> .Empty;
}
// - presence of unmanaged pattern has to be matched with `valuetype`
// - IsUnmanagedAttribute is allowed iff there is an unmanaged pattern
if (hasUnmanagedModreqPattern && (_flags & GenericParameterAttributes.NotNullableValueTypeConstraint) == 0 ||
hasUnmanagedModreqPattern != peModule.HasIsUnmanagedAttribute(_handle))
{
// we do not recognize these combinations as "unmanaged"
hasUnmanagedModreqPattern = false;
Interlocked.CompareExchange(ref _lazyConstraintsUseSiteErrorInfo, new CSDiagnosticInfo(ErrorCode.ERR_BindToBogus, this), CSDiagnosticInfo.EmptyErrorInfo);
}
_lazyHasIsUnmanagedConstraint = hasUnmanagedModreqPattern.ToThreeState();
ImmutableInterlocked.InterlockedInitialize(ref _lazyDeclaredConstraintTypes, declaredConstraintTypes);
}
return(_lazyDeclaredConstraintTypes);
}