LookupResult TypeChecker::lookupMember(DeclContext *dc,
                                       Type type, DeclName name,
                                       NameLookupOptions options) {
  assert(type->mayHaveMembers());

  LookupResult result;
  NLOptions subOptions = NL_QualifiedDefault;
  if (options.contains(NameLookupFlags::KnownPrivate))
    subOptions |= NL_KnownNonCascadingDependency;
  if (options.contains(NameLookupFlags::DynamicLookup))
    subOptions |= NL_DynamicLookup;
  if (options.contains(NameLookupFlags::IgnoreAccessibility))
    subOptions |= NL_IgnoreAccessibility;

  NominalTypeDecl *nominalLookupType = type->getAnyNominal();

  if (options.contains(NameLookupFlags::ProtocolMembers))
    subOptions |= NL_ProtocolMembers;

  // We handle our own overriding/shadowing filtering.
  subOptions &= ~NL_RemoveOverridden;
  subOptions &= ~NL_RemoveNonVisible;

  // Local function that performs lookup.
  auto doLookup = [&]() {
    result.clear();

    LookupResultBuilder builder(*this, result, dc, options,
                                /*memberLookup*/true);
    SmallVector<ValueDecl *, 4> lookupResults;
    dc->lookupQualified(type, name, subOptions, this, lookupResults);

    for (auto found : lookupResults) {
      builder.add(found, nominalLookupType, type);
    }
  };

  doLookup();

  if (result.empty()) {
    // If we didn't find anything, /and/ this is a nominal type, check to see
    // if any of the nominal's protocols are derivable and contain the
    // name we're looking for. (Note that we are not including extensions
    // here -- default derivation doesn't apply in extensions.)
    if (!nominalLookupType)
      return result;
    
    // Force the creation of any delayed members, to ensure proper member
    // lookup.
    this->forceExternalDeclMembers(nominalLookupType);

    // Perform the lookup again.
    // FIXME: This is only because forceExternalDeclMembers() might do something
    // interesting.
    doLookup();
  }

  return result;
}
Exemple #2
0
// Returns true on failure.
static bool
LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 
                         //SourceRange BaseRange,
                         const StructType *STy,
                         SourceLocation OpLoc) {
  StructTypeDecl *SDecl = STy->getDecl();
  DeclContext *DC = SDecl;

  // The record definition is complete, now look up the member.
  SemaRef.LookupQualifiedName(R, DC);

  if (!R.empty())
    return false;

#if 0
  // We didn't find anything with the given name, so try to correct
  // for typos.
  DeclarationName Name = R.getLookupName();
  RecordMemberExprValidatorCCC Validator;
  TypoCorrection Corrected = SemaRef.CorrectTypo(R.getLookupNameInfo(),
                                                 R.getLookupKind(), NULL,
                                                 &SS, Validator, DC);
  R.clear();
  if (NamedDecl *ND = Corrected.getCorrectionDecl()) {
    std::string CorrectedStr(
        Corrected.getAsString(SemaRef.getLangOpts()));
    std::string CorrectedQuotedStr(
        Corrected.getQuoted(SemaRef.getLangOpts()));
    R.setLookupName(Corrected.getCorrection());
    R.addDecl(ND);
    SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest)
      << Name << DC << CorrectedQuotedStr << SS.getRange()
      << FixItHint::CreateReplacement(Corrected.getCorrectionRange(),
                                      CorrectedStr);
    SemaRef.Diag(ND->getLocation(), diag::note_previous_decl)
      << ND->getDeclName();
  }
#endif

  // FIXME: Is this right? (also in clang)
  return false;
}
Exemple #3
0
  bool DeclExtractor::CheckTagDeclaration(TagDecl* NewTD,
                                          LookupResult& Previous){
    // If the decl is already known invalid, don't check it.
    if (NewTD->isInvalidDecl())
      return false;

    IdentifierInfo* Name = NewTD->getIdentifier();
    // If this is not a definition, it must have a name.
    assert((Name != 0 || NewTD->isThisDeclarationADefinition()) &&
           "Nameless record must be a definition!");

    // Figure out the underlying type if this a enum declaration. We need to do
    // this early, because it's needed to detect if this is an incompatible
    // redeclaration.

    TagDecl::TagKind Kind = NewTD->getTagKind();
    bool Invalid = false;
    assert(NewTD->getNumTemplateParameterLists() == 0
           && "Cannot handle that yet!");
    bool isExplicitSpecialization = false;

    if (Kind == TTK_Enum) {
      EnumDecl* ED = cast<EnumDecl>(NewTD);
      bool ScopedEnum = ED->isScoped();
      const QualType QT = ED->getIntegerType();

      if (QT.isNull() && ScopedEnum)
        // No underlying type explicitly specified, or we failed to parse the
        // type, default to int.
        ; //EnumUnderlying = m_Context->IntTy.getTypePtr();
      else if (!QT.isNull()) {
        // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
        // integral type; any cv-qualification is ignored.

        SourceLocation UnderlyingLoc;
        TypeSourceInfo* TI = 0;
        if ((TI = ED->getIntegerTypeSourceInfo()))
          UnderlyingLoc = TI->getTypeLoc().getBeginLoc();

        if (!QT->isDependentType() && !QT->isIntegralType(*m_Context)) {
          m_Sema->Diag(UnderlyingLoc, diag::err_enum_invalid_underlying)
            << QT;
        }
        if (TI)
          m_Sema->DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI,
                                                Sema::UPPC_FixedUnderlyingType);
      }
    }

    DeclContext *SearchDC = m_Sema->CurContext;
    DeclContext *DC = m_Sema->CurContext;
    //bool isStdBadAlloc = false;
    SourceLocation NameLoc = NewTD->getLocation();
    // if (Name && SS.isNotEmpty()) {
    //   // We have a nested-name tag ('struct foo::bar').

    //   // Check for invalid 'foo::'.
    //   if (SS.isInvalid()) {
    //     Name = 0;
    //     goto CreateNewDecl;
    //   }

    //   // If this is a friend or a reference to a class in a dependent
    //   // context, don't try to make a decl for it.
    //   if (TUK == TUK_Friend || TUK == TUK_Reference) {
    //     DC = computeDeclContext(SS, false);
    //     if (!DC) {
    //       IsDependent = true;
    //       return 0;
    //     }
    //   } else {
    //     DC = computeDeclContext(SS, true);
    //     if (!DC) {
    //       Diag(SS.getRange().getBegin(),
    //            diag::err_dependent_nested_name_spec)
    //         << SS.getRange();
    //       return 0;
    //     }
    //   }

    //   if (RequireCompleteDeclContext(SS, DC))
    //     return 0;

    //   SearchDC = DC;
    //   // Look-up name inside 'foo::'.
    //   LookupQualifiedName(Previous, DC);

    //   if (Previous.isAmbiguous())
    //     return 0;

    //   if (Previous.empty()) {
    //     // Name lookup did not find anything. However, if the
    //     // nested-name-specifier refers to the current instantiation,
    //     // and that current instantiation has any dependent base
    //     // classes, we might find something at instantiation time: treat
    //     // this as a dependent elaborated-type-specifier.
    //     // But this only makes any sense for reference-like lookups.
    //     if (Previous.wasNotFoundInCurrentInstantiation() &&
    //         (TUK == TUK_Reference || TUK == TUK_Friend)) {
    //       IsDependent = true;
    //       return 0;
    //     }

    //     // A tag 'foo::bar' must already exist.
    //     Diag(NameLoc, diag::err_not_tag_in_scope)
    //       << Kind << Name << DC << SS.getRange();
    //     Name = 0;
    //     Invalid = true;
    //   goto CreateNewDecl;
    // }
    //} else
    if (Name) {
      // If this is a named struct, check to see if there was a previous forward
      // declaration or definition.
      // FIXME: We're looking into outer scopes here, even when we
      // shouldn't be. Doing so can result in ambiguities that we
      // shouldn't be diagnosing.

      //LookupName(Previous, S);

      if (Previous.isAmbiguous()) {
        LookupResult::Filter F = Previous.makeFilter();
        while (F.hasNext()) {
          NamedDecl *ND = F.next();
          if (ND->getDeclContext()->getRedeclContext() != SearchDC)
            F.erase();
        }
        F.done();
      }

      // Note:  there used to be some attempt at recovery here.
      if (Previous.isAmbiguous()) {
        return false;
      }

      if (!m_Sema->getLangOpts().CPlusPlus) {
        // FIXME: This makes sure that we ignore the contexts associated
        // with C structs, unions, and enums when looking for a matching
        // tag declaration or definition. See the similar lookup tweak
        // in Sema::LookupName; is there a better way to deal with this?
        while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
          SearchDC = SearchDC->getParent();
      }
    } else if (m_Sema->getScopeForContext(m_Sema->CurContext)
               ->isFunctionPrototypeScope()) {
      // If this is an enum declaration in function prototype scope, set its
      // initial context to the translation unit.
      SearchDC = m_Context->getTranslationUnitDecl();
    }

    if (Previous.isSingleResult() &&
        Previous.getFoundDecl()->isTemplateParameter()) {
      // Maybe we will complain about the shadowed template parameter.
      m_Sema->DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
      // Just pretend that we didn't see the previous declaration.
      Previous.clear();
    }

    if (m_Sema->getLangOpts().CPlusPlus && Name && DC && m_Sema->StdNamespace
        && DC->Equals(m_Sema->getStdNamespace()) && Name->isStr("bad_alloc")) {
      // This is a declaration of or a reference to "std::bad_alloc".
      //isStdBadAlloc = true;

      if (Previous.empty() && m_Sema->StdBadAlloc) {
        // std::bad_alloc has been implicitly declared (but made invisible to
        // name lookup). Fill in this implicit declaration as the previous
        // declaration, so that the declarations get chained appropriately.
        Previous.addDecl(m_Sema->getStdBadAlloc());
      }
    }

    if (!Previous.empty()) {
      NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl();

      // It's okay to have a tag decl in the same scope as a typedef
      // which hides a tag decl in the same scope.  Finding this
      // insanity with a redeclaration lookup can only actually happen
      // in C++.
      //
      // This is also okay for elaborated-type-specifiers, which is
      // technically forbidden by the current standard but which is
      // okay according to the likely resolution of an open issue;
      // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
      if (m_Sema->getLangOpts().CPlusPlus) {
        if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
          if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
            TagDecl *Tag = TT->getDecl();
            if (Tag->getDeclName() == Name &&
                Tag->getDeclContext()->getRedeclContext()
                ->Equals(TD->getDeclContext()->getRedeclContext())) {
              PrevDecl = Tag;
              Previous.clear();
              Previous.addDecl(Tag);
              Previous.resolveKind();
            }
          }
        }
      }

      if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
        // If this is a use of a previous tag, or if the tag is already declared
        // in the same scope (so that the definition/declaration completes or
        // rementions the tag), reuse the decl.
        if (m_Sema->isDeclInScope(PrevDecl, SearchDC,
                                 m_Sema->getScopeForContext(m_Sema->CurContext),
                                  isExplicitSpecialization)) {
          // Make sure that this wasn't declared as an enum and now used as a
          // struct or something similar.
          SourceLocation KWLoc = NewTD->getLocStart();
          if (!m_Sema->isAcceptableTagRedeclaration(PrevTagDecl, Kind,
                                          NewTD->isThisDeclarationADefinition(),
                                                    KWLoc, *Name)) {
            bool SafeToContinue
              = (PrevTagDecl->getTagKind() != TTK_Enum && Kind != TTK_Enum);

            if (SafeToContinue)
              m_Sema->Diag(KWLoc, diag::err_use_with_wrong_tag)
                << Name
                << FixItHint::CreateReplacement(SourceRange(KWLoc),
                                                PrevTagDecl->getKindName());
            else
              m_Sema->Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
            m_Sema->Diag(PrevTagDecl->getLocation(), diag::note_previous_use);

            if (SafeToContinue)
              Kind = PrevTagDecl->getTagKind();
            else {
              // Recover by making this an anonymous redefinition.
              Name = 0;
              Previous.clear();
              Invalid = true;
            }
          }

          if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
            const EnumDecl *NewEnum = cast<EnumDecl>(NewTD);
            const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);

            // All conflicts with previous declarations are recovered by
            // returning the previous declaration.
            if (NewEnum->isScoped() != PrevEnum->isScoped()) {
              m_Sema->Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch)
                << PrevEnum->isScoped();
              m_Sema->Diag(PrevTagDecl->getLocation(), diag::note_previous_use);

              return false;
            }
            else if (PrevEnum->isFixed()) {
              QualType T = NewEnum->getIntegerType();

              if (!m_Context->hasSameUnqualifiedType(T,
                                                  PrevEnum->getIntegerType())) {
                m_Sema->Diag(NameLoc.isValid() ? NameLoc : KWLoc,
                             diag::err_enum_redeclare_type_mismatch)
                  << T
                  << PrevEnum->getIntegerType();
                m_Sema->Diag(PrevTagDecl->getLocation(),
                             diag::note_previous_use);

                return false;
              }
            }
            else if (NewEnum->isFixed() != PrevEnum->isFixed()) {
              m_Sema->Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch)
                << PrevEnum->isFixed();
              m_Sema->Diag(PrevTagDecl->getLocation(), diag::note_previous_use);

              return false;
            }
          }

          if (!Invalid) {
            // If this is a use, just return the declaration we found.

            // Diagnose attempts to redefine a tag.
            if (NewTD->isThisDeclarationADefinition()) {
              if (TagDecl* Def = PrevTagDecl->getDefinition()) {
                // If we're defining a specialization and the previous
                // definition is from an implicit instantiation, don't emit an
                // error here; we'll catch this in the general case below.
                if (!isExplicitSpecialization ||
                    !isa<CXXRecordDecl>(Def) ||
                    cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind()
                    == TSK_ExplicitSpecialization) {
                  m_Sema->Diag(NameLoc, diag::err_redefinition) << Name;
                  m_Sema->Diag(Def->getLocation(),
                               diag::note_previous_definition);
                  // If this is a redefinition, recover by making this
                  // struct be anonymous, which will make any later
                  // references get the previous definition.
                  Name = 0;
                  Previous.clear();
                  Invalid = true;
                }
              } else {
                // If the type is currently being defined, complain
                // about a nested redefinition.
                const TagType *Tag
                  = cast<TagType>(m_Context->getTagDeclType(PrevTagDecl));
                if (Tag->isBeingDefined()) {
                  m_Sema->Diag(NameLoc, diag::err_nested_redefinition) << Name;
                  m_Sema->Diag(PrevTagDecl->getLocation(),
                               diag::note_previous_definition);
                  Name = 0;
                  Previous.clear();
                  Invalid = true;
                }
              }

              // Okay, this is definition of a previously declared or referenced
              // tag PrevDecl. We're going to create a new Decl for it.
            }
          }
          // If we get here we have (another) forward declaration or we
          // have a definition.  Just create a new decl.

        } else {
          // If we get here, this is a definition of a new tag type in a nested
          // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
          // new decl/type.  We set PrevDecl to NULL so that the entities
          // have distinct types.
          Previous.clear();
        }
        // If we get here, we're going to create a new Decl. If PrevDecl
        // is non-NULL, it's a definition of the tag declared by
        // PrevDecl. If it's NULL, we have a new definition.


        // Otherwise, PrevDecl is not a tag, but was found with tag
        // lookup.  This is only actually possible in C++, where a few
        // things like templates still live in the tag namespace.
      } else {
        assert(m_Sema->getLangOpts().CPlusPlus);

        // Diagnose if the declaration is in scope.
        if (!m_Sema->isDeclInScope(PrevDecl, SearchDC,
                                 m_Sema->getScopeForContext(m_Sema->CurContext),
                                   isExplicitSpecialization)) {
          // do nothing

          // Otherwise it's a declaration.  Call out a particularly common
          // case here.
        } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
          unsigned Kind = 0;
          if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
          m_Sema->Diag(NameLoc, diag::err_tag_definition_of_typedef)
            << Name << Kind << TND->getUnderlyingType();
          m_Sema->Diag(PrevDecl->getLocation(),
                       diag::note_previous_decl) << PrevDecl;
          Invalid = true;

          // Otherwise, diagnose.
        } else {
          // The tag name clashes with something else in the target scope,
          // issue an error and recover by making this tag be anonymous.
          m_Sema->Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
          m_Sema->Diag(PrevDecl->getLocation(), diag::note_previous_definition);
          Name = 0;
          Invalid = true;
        }

        // The existing declaration isn't relevant to us; we're in a
        // new scope, so clear out the previous declaration.
        Previous.clear();
      }
    }
    if (Invalid) {
      return false;
    }

    return true;
  }
LookupResult TypeChecker::lookupMember(DeclContext *dc,
                                       Type type, DeclName name,
                                       NameLookupOptions options) {
  LookupResult result;
  NLOptions subOptions = NL_QualifiedDefault;
  if (options.contains(NameLookupFlags::KnownPrivate))
    subOptions |= NL_KnownNonCascadingDependency;
  if (options.contains(NameLookupFlags::DynamicLookup))
    subOptions |= NL_DynamicLookup;
  if (options.contains(NameLookupFlags::IgnoreAccessibility))
    subOptions |= NL_IgnoreAccessibility;

  // Dig out the type that we'll actually be looking into, and determine
  // whether it is a nominal type.
  Type lookupType = type;
  if (auto lvalueType = lookupType->getAs<LValueType>()) {
    lookupType = lvalueType->getObjectType();
  }
  if (auto metaType = lookupType->getAs<MetatypeType>()) {
    lookupType = metaType->getInstanceType();
  }
  NominalTypeDecl *nominalLookupType = lookupType->getAnyNominal();

  /// Whether to consider protocol members or not.
  bool considerProtocolMembers
    = nominalLookupType && !isa<ProtocolDecl>(nominalLookupType) &&
      options.contains(NameLookupFlags::ProtocolMembers);
  if (considerProtocolMembers)
    subOptions |= NL_ProtocolMembers;

  // We handle our own overriding/shadowing filtering.
  subOptions &= ~NL_RemoveOverridden;
  subOptions &= ~NL_RemoveNonVisible;

  // We can't have tuple types here; they need to be handled elsewhere.
  assert(!type->is<TupleType>());

  // Local function that performs lookup.
  auto doLookup = [&]() {
    result.clear();

    LookupResultBuilder builder(*this, result, dc, options,
                                considerProtocolMembers,
                                false);
    SmallVector<ValueDecl *, 4> lookupResults;
    dc->lookupQualified(type, name, subOptions, this, lookupResults);

    for (auto found : lookupResults) {
      builder.add(found, nominalLookupType, type);
    }
  };

  doLookup();

  if (result.empty()) {
    // If we didn't find anything, /and/ this is a nominal type, check to see
    // if any of the nominal's protocols are derivable and contain the
    // name we're looking for. (Note that we are not including extensions
    // here -- default derivation doesn't apply in extensions.)
    if (!nominalLookupType)
      return result;
    
    // Force the creation of any delayed members, to ensure proper member
    // lookup.
    this->forceExternalDeclMembers(nominalLookupType);

    // Perform the lookup again.
    // FIXME: This is only because forceExternalDeclMembers() might do something
    // interesting.
    doLookup();
  }

  return result;
}