Ejemplo n.º 1
0
DeclContext *DeclContext::getPrimaryContext() {
  switch (DeclKind) {
  case Decl::TranslationUnit:
  case Decl::LinkageSpec:
  case Decl::Block:
    // There is only one DeclContext for these entities.
    return this;

  case Decl::Namespace:
    // The original namespace is our primary context.
    return static_cast<NamespaceDecl*>(this)->getOriginalNamespace();

  case Decl::ObjCMethod:
    return this;

  case Decl::ObjCInterface:
    if (ObjCInterfaceDecl *Def = cast<ObjCInterfaceDecl>(this)->getDefinition())
      return Def;
      
    return this;
      
  case Decl::ObjCProtocol:
    // FIXME: Update when protocols properly model forward declarations.
    // For now, it's fine to fall through
      
  case Decl::ObjCCategory:
    return this;

  case Decl::ObjCImplementation:
  case Decl::ObjCCategoryImpl:
    return this;

  default:
    if (DeclKind >= Decl::firstTag && DeclKind <= Decl::lastTag) {
      // If this is a tag type that has a definition or is currently
      // being defined, that definition is our primary context.
      TagDecl *Tag = cast<TagDecl>(this);
      assert(isa<TagType>(Tag->TypeForDecl) ||
             isa<InjectedClassNameType>(Tag->TypeForDecl));

      if (TagDecl *Def = Tag->getDefinition())
        return Def;

      if (!isa<InjectedClassNameType>(Tag->TypeForDecl)) {
        const TagType *TagTy = cast<TagType>(Tag->TypeForDecl);
        if (TagTy->isBeingDefined())
          // FIXME: is it necessarily being defined in the decl
          // that owns the type?
          return TagTy->getDecl();
      }

      return Tag;
    }

    assert(DeclKind >= Decl::firstFunction && DeclKind <= Decl::lastFunction &&
          "Unknown DeclContext kind");
    return this;
  }
}
Ejemplo n.º 2
0
/// \brief Require that the context specified by SS be complete.
///
/// If SS refers to a type, this routine checks whether the type is
/// complete enough (or can be made complete enough) for name lookup
/// into the DeclContext. A type that is not yet completed can be
/// considered "complete enough" if it is a class/struct/union/enum
/// that is currently being defined. Or, if we have a type that names
/// a class template specialization that is not a complete type, we
/// will attempt to instantiate that class template.
bool Sema::RequireCompleteDeclContext(CXXScopeSpec &SS,
                                      DeclContext *&DC) {
  assert(DC && "given null context");

  TagDecl *tag = dyn_cast<TagDecl>(DC);

  // If this is a dependent type, then we consider it complete.
  // FIXME: This is wrong; we should require a (visible) definition to
  // exist in this case too.
  if (!tag || tag->isDependentContext())
    return false;

  // If we're currently defining this type, then lookup into the
  // type is okay: don't complain that it isn't complete yet.
  QualType type = Context.getTypeDeclType(tag);
  const TagType *tagType = type->getAs<TagType>();
  if (tagType && tagType->isBeingDefined())
    return false;

  SourceLocation loc = SS.getLastQualifierNameLoc();
  if (loc.isInvalid()) loc = SS.getRange().getBegin();

  // The type must be complete.
  if (RequireCompleteType(loc, type, diag::err_incomplete_nested_name_spec,
                          SS.getRange())) {
    // The actual information about the decl may have been loaded via an
    // external source that created a new AST node/decl for the definition
    // rather than reusing the one we had (DC) like the ASTReader does.
    // To avoid the caller to continue using the still incomplete decl, let's
    // set it to the definition.
    DC = tag->getDefinition();
    SS.SetInvalid(SS.getRange());
    return true;
  }

  // Fixed enum types are complete, but they aren't valid as scopes
  // until we see a definition, so awkwardly pull out this special
  // case.
  const EnumType *enumType = dyn_cast_or_null<EnumType>(tagType);
  if (!enumType)
    return false;
  if (enumType->getDecl()->isCompleteDefinition()) {
    // If we know about the definition but it is not visible, complain.
    NamedDecl *SuggestedDef = nullptr;
    if (!hasVisibleDefinition(enumType->getDecl(), &SuggestedDef,
                              /*OnlyNeedComplete*/false)) {
      // If the user is going to see an error here, recover by making the
      // definition visible.
      bool TreatAsComplete = !isSFINAEContext();
      diagnoseMissingImport(loc, SuggestedDef, MissingImportKind::Definition,
                            /*Recover*/TreatAsComplete);
      return !TreatAsComplete;
    }
    return false;
  }

  // Try to instantiate the definition, if this is a specialization of an
  // enumeration temploid.
  EnumDecl *ED = enumType->getDecl();
  if (EnumDecl *Pattern = ED->getInstantiatedFromMemberEnum()) {
    MemberSpecializationInfo *MSI = ED->getMemberSpecializationInfo();
    if (MSI->getTemplateSpecializationKind() != TSK_ExplicitSpecialization) {
      if (InstantiateEnum(loc, ED, Pattern, getTemplateInstantiationArgs(ED),
                          TSK_ImplicitInstantiation)) {
        SS.SetInvalid(SS.getRange());
        return true;
      }
      return false;
    }
  }

  Diag(loc, diag::err_incomplete_nested_name_spec)
    << type << SS.getRange();
  SS.SetInvalid(SS.getRange());
  return true;
}