/usr/src/gnu/usr.bin/clang/libclangSerialization/../../../llvm/clang/lib/Serialization/ASTReaderDecl.cpp

Bug Summary

File:	src/gnu/usr.bin/clang/libclangSerialization/../../../llvm/clang/lib/Serialization/ASTReaderDecl.cpp
Warning:	line 2510, column 16 Called C++ object pointer is null
Annotated Source Code

Press '?' to see keyboard shortcuts
Show analyzer invocation
clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ASTReaderDecl.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model static -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/clang/libclangSerialization/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/libclangSerialization/../../../llvm/clang/include -I /usr/src/gnu/usr.bin/clang/libclangSerialization/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/libclangSerialization/../include -I /usr/src/gnu/usr.bin/clang/libclangSerialization/obj -I /usr/src/gnu/usr.bin/clang/libclangSerialization/obj/../include -D NDEBUG -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D LLVM_PREFIX="/usr" -internal-isystem /usr/include/c++/v1 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/usr/src/gnu/usr.bin/clang/libclangSerialization/obj -ferror-limit 19 -fvisibility-inlines-hidden -fwrapv -stack-protector 2 -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c++ /usr/src/gnu/usr.bin/clang/libclangSerialization/../../../llvm/clang/lib/Serialization/ASTReaderDecl.cpp
1//===- ASTReaderDecl.cpp - Decl Deserialization ---------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the ASTReader::readDeclRecord method, which is the
10// entrypoint for loading a decl.
11//
12//===----------------------------------------------------------------------===//

14#include "ASTCommon.h"
15#include "ASTReaderInternals.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/Attr.h"
18#include "clang/AST/AttrIterator.h"
19#include "clang/AST/Decl.h"
20#include "clang/AST/DeclBase.h"
21#include "clang/AST/DeclCXX.h"
22#include "clang/AST/DeclFriend.h"
23#include "clang/AST/DeclObjC.h"
24#include "clang/AST/DeclOpenMP.h"
25#include "clang/AST/DeclTemplate.h"
26#include "clang/AST/DeclVisitor.h"
27#include "clang/AST/DeclarationName.h"
28#include "clang/AST/Expr.h"
29#include "clang/AST/ExternalASTSource.h"
30#include "clang/AST/LambdaCapture.h"
31#include "clang/AST/NestedNameSpecifier.h"
32#include "clang/AST/OpenMPClause.h"
33#include "clang/AST/Redeclarable.h"
34#include "clang/AST/Stmt.h"
35#include "clang/AST/TemplateBase.h"
36#include "clang/AST/Type.h"
37#include "clang/AST/UnresolvedSet.h"
38#include "clang/Basic/AttrKinds.h"
39#include "clang/Basic/ExceptionSpecificationType.h"
40#include "clang/Basic/IdentifierTable.h"
41#include "clang/Basic/LLVM.h"
42#include "clang/Basic/Lambda.h"
43#include "clang/Basic/LangOptions.h"
44#include "clang/Basic/Linkage.h"
45#include "clang/Basic/Module.h"
46#include "clang/Basic/PragmaKinds.h"
47#include "clang/Basic/SourceLocation.h"
48#include "clang/Basic/Specifiers.h"
49#include "clang/Sema/IdentifierResolver.h"
50#include "clang/Serialization/ASTBitCodes.h"
51#include "clang/Serialization/ASTRecordReader.h"
52#include "clang/Serialization/ContinuousRangeMap.h"
53#include "clang/Serialization/ModuleFile.h"
54#include "llvm/ADT/DenseMap.h"
55#include "llvm/ADT/FoldingSet.h"
56#include "llvm/ADT/STLExtras.h"
57#include "llvm/ADT/SmallPtrSet.h"
58#include "llvm/ADT/SmallVector.h"
59#include "llvm/ADT/iterator_range.h"
60#include "llvm/Bitstream/BitstreamReader.h"
61#include "llvm/Support/Casting.h"
62#include "llvm/Support/ErrorHandling.h"
63#include "llvm/Support/SaveAndRestore.h"
64#include <algorithm>
65#include <cassert>
66#include <cstdint>
67#include <cstring>
68#include <string>
69#include <utility>

71using namespace clang;
72using namespace serialization;

74//===----------------------------------------------------------------------===//
75// Declaration deserialization
76//===----------------------------------------------------------------------===//

78namespace clang {

class ASTDeclReader : public DeclVisitor<ASTDeclReader, void> {
  ASTReader &Reader;
  ASTRecordReader &Record;
  ASTReader::RecordLocation Loc;
  const DeclID ThisDeclID;
  const SourceLocation ThisDeclLoc;

  using RecordData = ASTReader::RecordData;

  TypeID DeferredTypeID = 0;
  unsigned AnonymousDeclNumber;
  GlobalDeclID NamedDeclForTagDecl = 0;
  IdentifierInfo *TypedefNameForLinkage = nullptr;

  bool HasPendingBody = false;

  ///A flag to carry the information for a decl from the entity is
  /// used. We use it to delay the marking of the canonical decl as used until
  /// the entire declaration is deserialized and merged.
  bool IsDeclMarkedUsed = false;

  uint64_t GetCurrentCursorOffset();

  uint64_t ReadLocalOffset() {
    uint64_t LocalOffset = Record.readInt();
    assert(LocalOffset < Loc.Offset && "offset point after current record")((void)0);
    return LocalOffset ? Loc.Offset - LocalOffset : 0;
  }

  uint64_t ReadGlobalOffset() {
    uint64_t Local = ReadLocalOffset();
    return Local ? Record.getGlobalBitOffset(Local) : 0;
  }

  SourceLocation readSourceLocation() {
    return Record.readSourceLocation();
  }

  SourceRange readSourceRange() {
    return Record.readSourceRange();
  }

  TypeSourceInfo *readTypeSourceInfo() {
    return Record.readTypeSourceInfo();
  }

  serialization::DeclID readDeclID() {
    return Record.readDeclID();
  }

  std::string readString() {
    return Record.readString();
  }

  void readDeclIDList(SmallVectorImpl<DeclID> &IDs) {
    for (unsigned I = 0, Size = Record.readInt(); I != Size; ++I)
      IDs.push_back(readDeclID());
  }

  Decl *readDecl() {
    return Record.readDecl();
  }

  template<typename T>
  T *readDeclAs() {
    return Record.readDeclAs<T>();
  }

  serialization::SubmoduleID readSubmoduleID() {
    if (Record.getIdx() == Record.size())
      return 0;

    return Record.getGlobalSubmoduleID(Record.readInt());
  }

  Module *readModule() {
    return Record.getSubmodule(readSubmoduleID());
  }

  void ReadCXXRecordDefinition(CXXRecordDecl *D, bool Update);
  void ReadCXXDefinitionData(struct CXXRecordDecl::DefinitionData &Data,
                             const CXXRecordDecl *D);
  void MergeDefinitionData(CXXRecordDecl *D,
                           struct CXXRecordDecl::DefinitionData &&NewDD);
  void ReadObjCDefinitionData(struct ObjCInterfaceDecl::DefinitionData &Data);
  void MergeDefinitionData(ObjCInterfaceDecl *D,
                           struct ObjCInterfaceDecl::DefinitionData &&NewDD);
  void ReadObjCDefinitionData(struct ObjCProtocolDecl::DefinitionData &Data);
  void MergeDefinitionData(ObjCProtocolDecl *D,
                           struct ObjCProtocolDecl::DefinitionData &&NewDD);

  static DeclContext *getPrimaryDCForAnonymousDecl(DeclContext *LexicalDC);

  static NamedDecl *getAnonymousDeclForMerging(ASTReader &Reader,
                                               DeclContext *DC,
                                               unsigned Index);
  static void setAnonymousDeclForMerging(ASTReader &Reader, DeclContext *DC,
                                         unsigned Index, NamedDecl *D);

  /// Results from loading a RedeclarableDecl.
  class RedeclarableResult {
    Decl *MergeWith;
    GlobalDeclID FirstID;
    bool IsKeyDecl;

  public:
    RedeclarableResult(Decl *MergeWith, GlobalDeclID FirstID, bool IsKeyDecl)
        : MergeWith(MergeWith), FirstID(FirstID), IsKeyDecl(IsKeyDecl) {}

    /// Retrieve the first ID.
    GlobalDeclID getFirstID() const { return FirstID; }

    /// Is this declaration a key declaration?
    bool isKeyDecl() const { return IsKeyDecl; }

    /// Get a known declaration that this should be merged with, if
    /// any.
    Decl *getKnownMergeTarget() const { return MergeWith; }
  };

  /// Class used to capture the result of searching for an existing
  /// declaration of a specific kind and name, along with the ability
  /// to update the place where this result was found (the declaration
  /// chain hanging off an identifier or the DeclContext we searched in)
  /// if requested.
  class FindExistingResult {
    ASTReader &Reader;
    NamedDecl *New = nullptr;
    NamedDecl *Existing = nullptr;
    bool AddResult = false;
    unsigned AnonymousDeclNumber = 0;
    IdentifierInfo *TypedefNameForLinkage = nullptr;

  public:
    FindExistingResult(ASTReader &Reader) : Reader(Reader) {}

    FindExistingResult(ASTReader &Reader, NamedDecl *New, NamedDecl *Existing,
                       unsigned AnonymousDeclNumber,
                       IdentifierInfo *TypedefNameForLinkage)
        : Reader(Reader), New(New), Existing(Existing), AddResult(true),
          AnonymousDeclNumber(AnonymousDeclNumber),
          TypedefNameForLinkage(TypedefNameForLinkage) {}

    FindExistingResult(FindExistingResult &&Other)
        : Reader(Other.Reader), New(Other.New), Existing(Other.Existing),
          AddResult(Other.AddResult),
          AnonymousDeclNumber(Other.AnonymousDeclNumber),
          TypedefNameForLinkage(Other.TypedefNameForLinkage) {
      Other.AddResult = false;
    }

    FindExistingResult &operator=(FindExistingResult &&) = delete;
    ~FindExistingResult();

    /// Suppress the addition of this result into the known set of
    /// names.
    void suppress() { AddResult = false; }

    operator NamedDecl*() const { return Existing; }

    template<typename T>
    operator T*() const { return dyn_cast_or_null<T>(Existing); }
  };

  static DeclContext *getPrimaryContextForMerging(ASTReader &Reader,
                                                  DeclContext *DC);
  FindExistingResult findExisting(NamedDecl *D);

public:
  ASTDeclReader(ASTReader &Reader, ASTRecordReader &Record,
                ASTReader::RecordLocation Loc,
                DeclID thisDeclID, SourceLocation ThisDeclLoc)
      : Reader(Reader), Record(Record), Loc(Loc), ThisDeclID(thisDeclID),
        ThisDeclLoc(ThisDeclLoc) {}

  template <typename T> static
  void AddLazySpecializations(T *D,
                              SmallVectorImpl<serialization::DeclID>& IDs) {
    if (IDs.empty())
      return;

    // FIXME: We should avoid this pattern of getting the ASTContext.
    ASTContext &C = D->getASTContext();

    auto *&LazySpecializations = D->getCommonPtr()->LazySpecializations;

    if (auto &Old = LazySpecializations) {
      IDs.insert(IDs.end(), Old + 1, Old + 1 + Old[0]);
      llvm::sort(IDs);
      IDs.erase(std::unique(IDs.begin(), IDs.end()), IDs.end());
    }

    auto *Result = new (C) serialization::DeclID[1 + IDs.size()];
    *Result = IDs.size();
    std::copy(IDs.begin(), IDs.end(), Result + 1);

    LazySpecializations = Result;
  }

  template <typename DeclT>
  static Decl *getMostRecentDeclImpl(Redeclarable<DeclT> *D);
  static Decl *getMostRecentDeclImpl(...);
  static Decl *getMostRecentDecl(Decl *D);

  static void mergeInheritableAttributes(ASTReader &Reader, Decl *D,
                                         Decl *Previous);

  template <typename DeclT>
  static void attachPreviousDeclImpl(ASTReader &Reader,
                                     Redeclarable<DeclT> *D, Decl *Previous,
                                     Decl *Canon);
  static void attachPreviousDeclImpl(ASTReader &Reader, ...);
  static void attachPreviousDecl(ASTReader &Reader, Decl *D, Decl *Previous,
                                 Decl *Canon);

  template <typename DeclT>
  static void attachLatestDeclImpl(Redeclarable<DeclT> *D, Decl *Latest);
  static void attachLatestDeclImpl(...);
  static void attachLatestDecl(Decl *D, Decl *latest);

  template <typename DeclT>
  static void markIncompleteDeclChainImpl(Redeclarable<DeclT> *D);
  static void markIncompleteDeclChainImpl(...);

  /// Determine whether this declaration has a pending body.
  bool hasPendingBody() const { return HasPendingBody; }

  void ReadFunctionDefinition(FunctionDecl *FD);
  void Visit(Decl *D);

  void UpdateDecl(Decl *D, SmallVectorImpl<serialization::DeclID> &);

  static void setNextObjCCategory(ObjCCategoryDecl *Cat,
                                  ObjCCategoryDecl *Next) {
    Cat->NextClassCategory = Next;
  }

  void VisitDecl(Decl *D);
  void VisitPragmaCommentDecl(PragmaCommentDecl *D);
  void VisitPragmaDetectMismatchDecl(PragmaDetectMismatchDecl *D);
  void VisitTranslationUnitDecl(TranslationUnitDecl *TU);
  void VisitNamedDecl(NamedDecl *ND);
  void VisitLabelDecl(LabelDecl *LD);
  void VisitNamespaceDecl(NamespaceDecl *D);
  void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
  void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
  void VisitTypeDecl(TypeDecl *TD);
  RedeclarableResult VisitTypedefNameDecl(TypedefNameDecl *TD);
  void VisitTypedefDecl(TypedefDecl *TD);
  void VisitTypeAliasDecl(TypeAliasDecl *TD);
  void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
  void VisitUnresolvedUsingIfExistsDecl(UnresolvedUsingIfExistsDecl *D);
  RedeclarableResult VisitTagDecl(TagDecl *TD);
  void VisitEnumDecl(EnumDecl *ED);
  RedeclarableResult VisitRecordDeclImpl(RecordDecl *RD);
  void VisitRecordDecl(RecordDecl *RD) { VisitRecordDeclImpl(RD); }
  RedeclarableResult VisitCXXRecordDeclImpl(CXXRecordDecl *D);
  void VisitCXXRecordDecl(CXXRecordDecl *D) { VisitCXXRecordDeclImpl(D); }
  RedeclarableResult VisitClassTemplateSpecializationDeclImpl(
                                          ClassTemplateSpecializationDecl *D);

  void VisitClassTemplateSpecializationDecl(
      ClassTemplateSpecializationDecl *D) {
    VisitClassTemplateSpecializationDeclImpl(D);
  }

  void VisitClassTemplatePartialSpecializationDecl(
                                   ClassTemplatePartialSpecializationDecl *D);
  void VisitClassScopeFunctionSpecializationDecl(
                                     ClassScopeFunctionSpecializationDecl *D);
  RedeclarableResult
  VisitVarTemplateSpecializationDeclImpl(VarTemplateSpecializationDecl *D);

  void VisitVarTemplateSpecializationDecl(VarTemplateSpecializationDecl *D) {
    VisitVarTemplateSpecializationDeclImpl(D);
  }

  void VisitVarTemplatePartialSpecializationDecl(
      VarTemplatePartialSpecializationDecl *D);
  void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
  void VisitValueDecl(ValueDecl *VD);
  void VisitEnumConstantDecl(EnumConstantDecl *ECD);
  void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
  void VisitDeclaratorDecl(DeclaratorDecl *DD);
  void VisitFunctionDecl(FunctionDecl *FD);
  void VisitCXXDeductionGuideDecl(CXXDeductionGuideDecl *GD);
  void VisitCXXMethodDecl(CXXMethodDecl *D);
  void VisitCXXConstructorDecl(CXXConstructorDecl *D);
  void VisitCXXDestructorDecl(CXXDestructorDecl *D);
  void VisitCXXConversionDecl(CXXConversionDecl *D);
  void VisitFieldDecl(FieldDecl *FD);
  void VisitMSPropertyDecl(MSPropertyDecl *FD);
  void VisitMSGuidDecl(MSGuidDecl *D);
  void VisitTemplateParamObjectDecl(TemplateParamObjectDecl *D);
  void VisitIndirectFieldDecl(IndirectFieldDecl *FD);
  RedeclarableResult VisitVarDeclImpl(VarDecl *D);
  void VisitVarDecl(VarDecl *VD) { VisitVarDeclImpl(VD); }
  void VisitImplicitParamDecl(ImplicitParamDecl *PD);
  void VisitParmVarDecl(ParmVarDecl *PD);
  void VisitDecompositionDecl(DecompositionDecl *DD);
  void VisitBindingDecl(BindingDecl *BD);
  void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
  DeclID VisitTemplateDecl(TemplateDecl *D);
  void VisitConceptDecl(ConceptDecl *D);
  void VisitRequiresExprBodyDecl(RequiresExprBodyDecl *D);
  RedeclarableResult VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
  void VisitClassTemplateDecl(ClassTemplateDecl *D);
  void VisitBuiltinTemplateDecl(BuiltinTemplateDecl *D);
  void VisitVarTemplateDecl(VarTemplateDecl *D);
  void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
  void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
  void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
  void VisitUsingDecl(UsingDecl *D);
  void VisitUsingEnumDecl(UsingEnumDecl *D);
  void VisitUsingPackDecl(UsingPackDecl *D);
  void VisitUsingShadowDecl(UsingShadowDecl *D);
  void VisitConstructorUsingShadowDecl(ConstructorUsingShadowDecl *D);
  void VisitLinkageSpecDecl(LinkageSpecDecl *D);
  void VisitExportDecl(ExportDecl *D);
  void VisitFileScopeAsmDecl(FileScopeAsmDecl *AD);
  void VisitImportDecl(ImportDecl *D);
  void VisitAccessSpecDecl(AccessSpecDecl *D);
  void VisitFriendDecl(FriendDecl *D);
  void VisitFriendTemplateDecl(FriendTemplateDecl *D);
  void VisitStaticAssertDecl(StaticAssertDecl *D);
  void VisitBlockDecl(BlockDecl *BD);
  void VisitCapturedDecl(CapturedDecl *CD);
  void VisitEmptyDecl(EmptyDecl *D);
  void VisitLifetimeExtendedTemporaryDecl(LifetimeExtendedTemporaryDecl *D);

  std::pair<uint64_t, uint64_t> VisitDeclContext(DeclContext *DC);

  template<typename T>
  RedeclarableResult VisitRedeclarable(Redeclarable<T> *D);

  template<typename T>
  void mergeRedeclarable(Redeclarable<T> *D, RedeclarableResult &Redecl,
                         DeclID TemplatePatternID = 0);

  template<typename T>
  void mergeRedeclarable(Redeclarable<T> *D, T *Existing,
                         RedeclarableResult &Redecl,
                         DeclID TemplatePatternID = 0);

  template<typename T>
  void mergeMergeable(Mergeable<T> *D);

  void mergeMergeable(LifetimeExtendedTemporaryDecl *D);

  void mergeTemplatePattern(RedeclarableTemplateDecl *D,
                            RedeclarableTemplateDecl *Existing,
                            DeclID DsID, bool IsKeyDecl);

  ObjCTypeParamList *ReadObjCTypeParamList();

  // FIXME: Reorder according to DeclNodes.td?
  void VisitObjCMethodDecl(ObjCMethodDecl *D);
  void VisitObjCTypeParamDecl(ObjCTypeParamDecl *D);
  void VisitObjCContainerDecl(ObjCContainerDecl *D);
  void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
  void VisitObjCIvarDecl(ObjCIvarDecl *D);
  void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
  void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
  void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
  void VisitObjCImplDecl(ObjCImplDecl *D);
  void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
  void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
  void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
  void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
  void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
  void VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D);
  void VisitOMPAllocateDecl(OMPAllocateDecl *D);
  void VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D);
  void VisitOMPDeclareMapperDecl(OMPDeclareMapperDecl *D);
  void VisitOMPRequiresDecl(OMPRequiresDecl *D);
  void VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D);
};

458} // namespace clang

460namespace {

462/// Iterator over the redeclarations of a declaration that have already
463/// been merged into the same redeclaration chain.
464template<typename DeclT>
465class MergedRedeclIterator {
DeclT *Start;
DeclT *Canonical = nullptr;
DeclT *Current = nullptr;

470public:
MergedRedeclIterator() = default;
MergedRedeclIterator(DeclT *Start) : Start(Start), Current(Start) {}

DeclT *operator*() { return Current; }

MergedRedeclIterator &operator++() {
  if (Current->isFirstDecl()) {
    Canonical = Current;
    Current = Current->getMostRecentDecl();
  } else
    Current = Current->getPreviousDecl();

  // If we started in the merged portion, we'll reach our start position
  // eventually. Otherwise, we'll never reach it, but the second declaration
  // we reached was the canonical declaration, so stop when we see that one
  // again.
  if (Current == Start || Current == Canonical)
    Current = nullptr;
  return *this;
}

friend bool operator!=(const MergedRedeclIterator &A,
                       const MergedRedeclIterator &B) {
  return A.Current != B.Current;
}
496};

498} // namespace

500template <typename DeclT>
501static llvm::iterator_range<MergedRedeclIterator<DeclT>>
502merged_redecls(DeclT *D) {
return llvm::make_range(MergedRedeclIterator<DeclT>(D),
                        MergedRedeclIterator<DeclT>());
505}

507uint64_t ASTDeclReader::GetCurrentCursorOffset() {
return Loc.F->DeclsCursor.GetCurrentBitNo() + Loc.F->GlobalBitOffset;
509}

511void ASTDeclReader::ReadFunctionDefinition(FunctionDecl *FD) {
if (Record.readInt()) {
  Reader.DefinitionSource[FD] =
      Loc.F->Kind == ModuleKind::MK_MainFile ||
      Reader.getContext().getLangOpts().BuildingPCHWithObjectFile;
}
if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
  CD->setNumCtorInitializers(Record.readInt());
  if (CD->getNumCtorInitializers())
    CD->CtorInitializers = ReadGlobalOffset();
}
// Store the offset of the body so we can lazily load it later.
Reader.PendingBodies[FD] = GetCurrentCursorOffset();
HasPendingBody = true;
525}

527void ASTDeclReader::Visit(Decl *D) {
DeclVisitor<ASTDeclReader, void>::Visit(D);

// At this point we have deserialized and merged the decl and it is safe to
// update its canonical decl to signal that the entire entity is used.
D->getCanonicalDecl()->Used |= IsDeclMarkedUsed;
IsDeclMarkedUsed = false;

if (auto *DD = dyn_cast<DeclaratorDecl>(D)) {
  if (auto *TInfo = DD->getTypeSourceInfo())
    Record.readTypeLoc(TInfo->getTypeLoc());
}

if (auto *TD = dyn_cast<TypeDecl>(D)) {
  // We have a fully initialized TypeDecl. Read its type now.
  TD->setTypeForDecl(Reader.GetType(DeferredTypeID).getTypePtrOrNull());

  // If this is a tag declaration with a typedef name for linkage, it's safe
  // to load that typedef now.
  if (NamedDeclForTagDecl)
    cast<TagDecl>(D)->TypedefNameDeclOrQualifier =
        cast<TypedefNameDecl>(Reader.GetDecl(NamedDeclForTagDecl));
} else if (auto *ID = dyn_cast<ObjCInterfaceDecl>(D)) {
  // if we have a fully initialized TypeDecl, we can safely read its type now.
  ID->TypeForDecl = Reader.GetType(DeferredTypeID).getTypePtrOrNull();
} else if (auto *FD = dyn_cast<FunctionDecl>(D)) {
  // FunctionDecl's body was written last after all other Stmts/Exprs.
  // We only read it if FD doesn't already have a body (e.g., from another
  // module).
  // FIXME: Can we diagnose ODR violations somehow?
  if (Record.readInt())
    ReadFunctionDefinition(FD);
}
560}

562void ASTDeclReader::VisitDecl(Decl *D) {
if (D->isTemplateParameter() || D->isTemplateParameterPack() ||
    isa<ParmVarDecl>(D) || isa<ObjCTypeParamDecl>(D)) {
  // We don't want to deserialize the DeclContext of a template
  // parameter or of a parameter of a function template immediately.   These
  // entities might be used in the formulation of its DeclContext (for
  // example, a function parameter can be used in decltype() in trailing
  // return type of the function).  Use the translation unit DeclContext as a
  // placeholder.
  GlobalDeclID SemaDCIDForTemplateParmDecl = readDeclID();
  GlobalDeclID LexicalDCIDForTemplateParmDecl = readDeclID();
  if (!LexicalDCIDForTemplateParmDecl)
    LexicalDCIDForTemplateParmDecl = SemaDCIDForTemplateParmDecl;
  Reader.addPendingDeclContextInfo(D,
                                   SemaDCIDForTemplateParmDecl,
                                   LexicalDCIDForTemplateParmDecl);
  D->setDeclContext(Reader.getContext().getTranslationUnitDecl());
} else {
  auto *SemaDC = readDeclAs<DeclContext>();
  auto *LexicalDC = readDeclAs<DeclContext>();
  if (!LexicalDC)
    LexicalDC = SemaDC;
  DeclContext *MergedSemaDC = Reader.MergedDeclContexts.lookup(SemaDC);
  // Avoid calling setLexicalDeclContext() directly because it uses
  // Decl::getASTContext() internally which is unsafe during derialization.
  D->setDeclContextsImpl(MergedSemaDC ? MergedSemaDC : SemaDC, LexicalDC,
                         Reader.getContext());
}
D->setLocation(ThisDeclLoc);
D->InvalidDecl = Record.readInt();
if (Record.readInt()) { // hasAttrs
  AttrVec Attrs;
  Record.readAttributes(Attrs);
  // Avoid calling setAttrs() directly because it uses Decl::getASTContext()
  // internally which is unsafe during derialization.
  D->setAttrsImpl(Attrs, Reader.getContext());
}
D->setImplicit(Record.readInt());
D->Used = Record.readInt();
IsDeclMarkedUsed |= D->Used;
D->setReferenced(Record.readInt());
D->setTopLevelDeclInObjCContainer(Record.readInt());
D->setAccess((AccessSpecifier)Record.readInt());
D->FromASTFile = true;
bool ModulePrivate = Record.readInt();

// Determine whether this declaration is part of a (sub)module. If so, it
// may not yet be visible.
if (unsigned SubmoduleID = readSubmoduleID()) {
  // Store the owning submodule ID in the declaration.
  D->setModuleOwnershipKind(
      ModulePrivate ? Decl::ModuleOwnershipKind::ModulePrivate
                    : Decl::ModuleOwnershipKind::VisibleWhenImported);
  D->setOwningModuleID(SubmoduleID);

  if (ModulePrivate) {
    // Module-private declarations are never visible, so there is no work to
    // do.
  } else if (Reader.getContext().getLangOpts().ModulesLocalVisibility) {
    // If local visibility is being tracked, this declaration will become
    // hidden and visible as the owning module does.
  } else if (Module *Owner = Reader.getSubmodule(SubmoduleID)) {
    // Mark the declaration as visible when its owning module becomes visible.
    if (Owner->NameVisibility == Module::AllVisible)
      D->setVisibleDespiteOwningModule();
    else
      Reader.HiddenNamesMap[Owner].push_back(D);
  }
} else if (ModulePrivate) {
  D->setModuleOwnershipKind(Decl::ModuleOwnershipKind::ModulePrivate);
}
633}

635void ASTDeclReader::VisitPragmaCommentDecl(PragmaCommentDecl *D) {
VisitDecl(D);
D->setLocation(readSourceLocation());
D->CommentKind = (PragmaMSCommentKind)Record.readInt();
std::string Arg = readString();
memcpy(D->getTrailingObjects<char>(), Arg.data(), Arg.size());
D->getTrailingObjects<char>()[Arg.size()] = '\0';
642}

644void ASTDeclReader::VisitPragmaDetectMismatchDecl(PragmaDetectMismatchDecl *D) {
VisitDecl(D);
D->setLocation(readSourceLocation());
std::string Name = readString();
memcpy(D->getTrailingObjects<char>(), Name.data(), Name.size());
D->getTrailingObjects<char>()[Name.size()] = '\0';

D->ValueStart = Name.size() + 1;
std::string Value = readString();
memcpy(D->getTrailingObjects<char>() + D->ValueStart, Value.data(),
       Value.size());
D->getTrailingObjects<char>()[D->ValueStart + Value.size()] = '\0';
656}

658void ASTDeclReader::VisitTranslationUnitDecl(TranslationUnitDecl *TU) {
llvm_unreachable("Translation units are not serialized")__builtin_unreachable();
660}

662void ASTDeclReader::VisitNamedDecl(NamedDecl *ND) {
VisitDecl(ND);
ND->setDeclName(Record.readDeclarationName());
AnonymousDeclNumber = Record.readInt();
666}

668void ASTDeclReader::VisitTypeDecl(TypeDecl *TD) {
VisitNamedDecl(TD);
TD->setLocStart(readSourceLocation());
// Delay type reading until after we have fully initialized the decl.
DeferredTypeID = Record.getGlobalTypeID(Record.readInt());
673}

675ASTDeclReader::RedeclarableResult
676ASTDeclReader::VisitTypedefNameDecl(TypedefNameDecl *TD) {
RedeclarableResult Redecl = VisitRedeclarable(TD);
VisitTypeDecl(TD);
TypeSourceInfo *TInfo = readTypeSourceInfo();
if (Record.readInt()) { // isModed
  QualType modedT = Record.readType();
  TD->setModedTypeSourceInfo(TInfo, modedT);
} else
  TD->setTypeSourceInfo(TInfo);
// Read and discard the declaration for which this is a typedef name for
// linkage, if it exists. We cannot rely on our type to pull in this decl,
// because it might have been merged with a type from another module and
// thus might not refer to our version of the declaration.
readDecl();
return Redecl;
691}

693void ASTDeclReader::VisitTypedefDecl(TypedefDecl *TD) {
RedeclarableResult Redecl = VisitTypedefNameDecl(TD);
mergeRedeclarable(TD, Redecl);
696}

698void ASTDeclReader::VisitTypeAliasDecl(TypeAliasDecl *TD) {
RedeclarableResult Redecl = VisitTypedefNameDecl(TD);
if (auto *Template = readDeclAs<TypeAliasTemplateDecl>())
  // Merged when we merge the template.
  TD->setDescribedAliasTemplate(Template);
else
  mergeRedeclarable(TD, Redecl);
705}

707ASTDeclReader::RedeclarableResult ASTDeclReader::VisitTagDecl(TagDecl *TD) {
RedeclarableResult Redecl = VisitRedeclarable(TD);
VisitTypeDecl(TD);

TD->IdentifierNamespace = Record.readInt();
TD->setTagKind((TagDecl::TagKind)Record.readInt());
if (!isa<CXXRecordDecl>(TD))
  TD->setCompleteDefinition(Record.readInt());
TD->setEmbeddedInDeclarator(Record.readInt());
TD->setFreeStanding(Record.readInt());
TD->setCompleteDefinitionRequired(Record.readInt());
TD->setBraceRange(readSourceRange());

switch (Record.readInt()) {
case 0:
  break;
case 1: { // ExtInfo
  auto *Info = new (Reader.getContext()) TagDecl::ExtInfo();
  Record.readQualifierInfo(*Info);
  TD->TypedefNameDeclOrQualifier = Info;
  break;
}
case 2: // TypedefNameForAnonDecl
  NamedDeclForTagDecl = readDeclID();
  TypedefNameForLinkage = Record.readIdentifier();
  break;
default:
  llvm_unreachable("unexpected tag info kind")__builtin_unreachable();
}

if (!isa<CXXRecordDecl>(TD))
  mergeRedeclarable(TD, Redecl);
return Redecl;
740}

742void ASTDeclReader::VisitEnumDecl(EnumDecl *ED) {
VisitTagDecl(ED);
if (TypeSourceInfo *TI = readTypeSourceInfo())
  ED->setIntegerTypeSourceInfo(TI);
else
  ED->setIntegerType(Record.readType());
ED->setPromotionType(Record.readType());
ED->setNumPositiveBits(Record.readInt());
ED->setNumNegativeBits(Record.readInt());
ED->setScoped(Record.readInt());
ED->setScopedUsingClassTag(Record.readInt());
ED->setFixed(Record.readInt());

ED->setHasODRHash(true);
ED->ODRHash = Record.readInt();

// If this is a definition subject to the ODR, and we already have a
// definition, merge this one into it.
if (ED->isCompleteDefinition() &&
    Reader.getContext().getLangOpts().Modules &&
    Reader.getContext().getLangOpts().CPlusPlus) {
  EnumDecl *&OldDef = Reader.EnumDefinitions[ED->getCanonicalDecl()];
  if (!OldDef) {
    // This is the first time we've seen an imported definition. Look for a
    // local definition before deciding that we are the first definition.
    for (auto *D : merged_redecls(ED->getCanonicalDecl())) {
      if (!D->isFromASTFile() && D->isCompleteDefinition()) {
        OldDef = D;
        break;
      }
    }
  }
  if (OldDef) {
    Reader.MergedDeclContexts.insert(std::make_pair(ED, OldDef));
    ED->setCompleteDefinition(false);
    Reader.mergeDefinitionVisibility(OldDef, ED);
    if (OldDef->getODRHash() != ED->getODRHash())
      Reader.PendingEnumOdrMergeFailures[OldDef].push_back(ED);
  } else {
    OldDef = ED;
  }
}

if (auto *InstED = readDeclAs<EnumDecl>()) {
  auto TSK = (TemplateSpecializationKind)Record.readInt();
  SourceLocation POI = readSourceLocation();
  ED->setInstantiationOfMemberEnum(Reader.getContext(), InstED, TSK);
  ED->getMemberSpecializationInfo()->setPointOfInstantiation(POI);
}
791}

793ASTDeclReader::RedeclarableResult
794ASTDeclReader::VisitRecordDeclImpl(RecordDecl *RD) {
RedeclarableResult Redecl = VisitTagDecl(RD);
RD->setHasFlexibleArrayMember(Record.readInt());
RD->setAnonymousStructOrUnion(Record.readInt());
RD->setHasObjectMember(Record.readInt());
RD->setHasVolatileMember(Record.readInt());
RD->setNonTrivialToPrimitiveDefaultInitialize(Record.readInt());
RD->setNonTrivialToPrimitiveCopy(Record.readInt());
RD->setNonTrivialToPrimitiveDestroy(Record.readInt());
RD->setHasNonTrivialToPrimitiveDefaultInitializeCUnion(Record.readInt());
RD->setHasNonTrivialToPrimitiveDestructCUnion(Record.readInt());
RD->setHasNonTrivialToPrimitiveCopyCUnion(Record.readInt());
RD->setParamDestroyedInCallee(Record.readInt());
RD->setArgPassingRestrictions((RecordDecl::ArgPassingKind)Record.readInt());
return Redecl;
809}

811void ASTDeclReader::VisitValueDecl(ValueDecl *VD) {
VisitNamedDecl(VD);
// For function declarations, defer reading the type in case the function has
// a deduced return type that references an entity declared within the
// function.
if (isa<FunctionDecl>(VD))
  DeferredTypeID = Record.getGlobalTypeID(Record.readInt());
else
  VD->setType(Record.readType());
820}

822void ASTDeclReader::VisitEnumConstantDecl(EnumConstantDecl *ECD) {
VisitValueDecl(ECD);
if (Record.readInt())
  ECD->setInitExpr(Record.readExpr());
ECD->setInitVal(Record.readAPSInt());
mergeMergeable(ECD);
828}

830void ASTDeclReader::VisitDeclaratorDecl(DeclaratorDecl *DD) {
VisitValueDecl(DD);
DD->setInnerLocStart(readSourceLocation());
if (Record.readInt()) { // hasExtInfo
  auto *Info = new (Reader.getContext()) DeclaratorDecl::ExtInfo();
  Record.readQualifierInfo(*Info);
  Info->TrailingRequiresClause = Record.readExpr();
  DD->DeclInfo = Info;
}
QualType TSIType = Record.readType();
DD->setTypeSourceInfo(
    TSIType.isNull() ? nullptr
                     : Reader.getContext().CreateTypeSourceInfo(TSIType));
843}

845void ASTDeclReader::VisitFunctionDecl(FunctionDecl *FD) {
RedeclarableResult Redecl = VisitRedeclarable(FD);
VisitDeclaratorDecl(FD);

// Attach a type to this function. Use the real type if possible, but fall
// back to the type as written if it involves a deduced return type.
if (FD->getTypeSourceInfo() &&
    FD->getTypeSourceInfo()->getType()->castAs<FunctionType>()
                           ->getReturnType()->getContainedAutoType()) {
  // We'll set up the real type in Visit, once we've finished loading the
  // function.
  FD->setType(FD->getTypeSourceInfo()->getType());
  Reader.PendingFunctionTypes.push_back({FD, DeferredTypeID});
} else {
  FD->setType(Reader.GetType(DeferredTypeID));
}
DeferredTypeID = 0;

FD->DNLoc = Record.readDeclarationNameLoc(FD->getDeclName());
FD->IdentifierNamespace = Record.readInt();

// FunctionDecl's body is handled last at ASTDeclReader::Visit,
// after everything else is read.

FD->setStorageClass(static_cast<StorageClass>(Record.readInt()));
FD->setInlineSpecified(Record.readInt());
FD->setImplicitlyInline(Record.readInt());
FD->setVirtualAsWritten(Record.readInt());
// We defer calling `FunctionDecl::setPure()` here as for methods of
// `CXXTemplateSpecializationDecl`s, we may not have connected up the
// definition (which is required for `setPure`).
const bool Pure = Record.readInt();
FD->setHasInheritedPrototype(Record.readInt());
FD->setHasWrittenPrototype(Record.readInt());
FD->setDeletedAsWritten(Record.readInt());
FD->setTrivial(Record.readInt());
FD->setTrivialForCall(Record.readInt());
FD->setDefaulted(Record.readInt());
FD->setExplicitlyDefaulted(Record.readInt());
FD->setHasImplicitReturnZero(Record.readInt());
FD->setConstexprKind(static_cast<ConstexprSpecKind>(Record.readInt()));
FD->setUsesSEHTry(Record.readInt());
FD->setHasSkippedBody(Record.readInt());
FD->setIsMultiVersion(Record.readInt());
FD->setLateTemplateParsed(Record.readInt());

FD->setCachedLinkage(static_cast<Linkage>(Record.readInt()));
FD->EndRangeLoc = readSourceLocation();

FD->ODRHash = Record.readInt();
FD->setHasODRHash(true);

if (FD->isDefaulted()) {
  if (unsigned NumLookups = Record.readInt()) {
    SmallVector<DeclAccessPair, 8> Lookups;
    for (unsigned I = 0; I != NumLookups; ++I) {
      NamedDecl *ND = Record.readDeclAs<NamedDecl>();
      AccessSpecifier AS = (AccessSpecifier)Record.readInt();
      Lookups.push_back(DeclAccessPair::make(ND, AS));
    }
    FD->setDefaultedFunctionInfo(FunctionDecl::DefaultedFunctionInfo::Create(
        Reader.getContext(), Lookups));
  }
}

switch ((FunctionDecl::TemplatedKind)Record.readInt()) {
case FunctionDecl::TK_NonTemplate:
  mergeRedeclarable(FD, Redecl);
  break;
case FunctionDecl::TK_FunctionTemplate:
  // Merged when we merge the template.
  FD->setDescribedFunctionTemplate(readDeclAs<FunctionTemplateDecl>());
  break;
case FunctionDecl::TK_MemberSpecialization: {
  auto *InstFD = readDeclAs<FunctionDecl>();
  auto TSK = (TemplateSpecializationKind)Record.readInt();
  SourceLocation POI = readSourceLocation();
  FD->setInstantiationOfMemberFunction(Reader.getContext(), InstFD, TSK);
  FD->getMemberSpecializationInfo()->setPointOfInstantiation(POI);
  mergeRedeclarable(FD, Redecl);
  break;
}
case FunctionDecl::TK_FunctionTemplateSpecialization: {
  auto *Template = readDeclAs<FunctionTemplateDecl>();
  auto TSK = (TemplateSpecializationKind)Record.readInt();

  // Template arguments.
  SmallVector<TemplateArgument, 8> TemplArgs;
  Record.readTemplateArgumentList(TemplArgs, /*Canonicalize*/ true);

  // Template args as written.
  SmallVector<TemplateArgumentLoc, 8> TemplArgLocs;
  SourceLocation LAngleLoc, RAngleLoc;
  bool HasTemplateArgumentsAsWritten = Record.readInt();
  if (HasTemplateArgumentsAsWritten) {
    unsigned NumTemplateArgLocs = Record.readInt();
    TemplArgLocs.reserve(NumTemplateArgLocs);
    for (unsigned i = 0; i != NumTemplateArgLocs; ++i)
      TemplArgLocs.push_back(Record.readTemplateArgumentLoc());

    LAngleLoc = readSourceLocation();
    RAngleLoc = readSourceLocation();
  }

  SourceLocation POI = readSourceLocation();

  ASTContext &C = Reader.getContext();
  TemplateArgumentList *TemplArgList
    = TemplateArgumentList::CreateCopy(C, TemplArgs);
  TemplateArgumentListInfo TemplArgsInfo(LAngleLoc, RAngleLoc);
  for (unsigned i = 0, e = TemplArgLocs.size(); i != e; ++i)
    TemplArgsInfo.addArgument(TemplArgLocs[i]);

  MemberSpecializationInfo *MSInfo = nullptr;
  if (Record.readInt()) {
    auto *FD = readDeclAs<FunctionDecl>();
    auto TSK = (TemplateSpecializationKind)Record.readInt();
    SourceLocation POI = readSourceLocation();

    MSInfo = new (C) MemberSpecializationInfo(FD, TSK);
    MSInfo->setPointOfInstantiation(POI);
  }

  FunctionTemplateSpecializationInfo *FTInfo =
      FunctionTemplateSpecializationInfo::Create(
          C, FD, Template, TSK, TemplArgList,
          HasTemplateArgumentsAsWritten ? &TemplArgsInfo : nullptr, POI,
          MSInfo);
  FD->TemplateOrSpecialization = FTInfo;

  if (FD->isCanonicalDecl()) { // if canonical add to template's set.
    // The template that contains the specializations set. It's not safe to
    // use getCanonicalDecl on Template since it may still be initializing.
    auto *CanonTemplate = readDeclAs<FunctionTemplateDecl>();
    // Get the InsertPos by FindNodeOrInsertPos() instead of calling
    // InsertNode(FTInfo) directly to avoid the getASTContext() call in
    // FunctionTemplateSpecializationInfo's Profile().
    // We avoid getASTContext because a decl in the parent hierarchy may
    // be initializing.
    llvm::FoldingSetNodeID ID;
    FunctionTemplateSpecializationInfo::Profile(ID, TemplArgs, C);
    void *InsertPos = nullptr;
    FunctionTemplateDecl::Common *CommonPtr = CanonTemplate->getCommonPtr();
    FunctionTemplateSpecializationInfo *ExistingInfo =
        CommonPtr->Specializations.FindNodeOrInsertPos(ID, InsertPos);
    if (InsertPos)
      CommonPtr->Specializations.InsertNode(FTInfo, InsertPos);
    else {
      assert(Reader.getContext().getLangOpts().Modules &&((void)0)
             "already deserialized this template specialization")((void)0);
      mergeRedeclarable(FD, ExistingInfo->getFunction(), Redecl);
    }
  }
  break;
}
case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
  // Templates.
  UnresolvedSet<8> TemplDecls;
  unsigned NumTemplates = Record.readInt();
  while (NumTemplates--)
    TemplDecls.addDecl(readDeclAs<NamedDecl>());

  // Templates args.
  TemplateArgumentListInfo TemplArgs;
  unsigned NumArgs = Record.readInt();
  while (NumArgs--)
    TemplArgs.addArgument(Record.readTemplateArgumentLoc());
  TemplArgs.setLAngleLoc(readSourceLocation());
  TemplArgs.setRAngleLoc(readSourceLocation());

  FD->setDependentTemplateSpecialization(Reader.getContext(),
                                         TemplDecls, TemplArgs);
  // These are not merged; we don't need to merge redeclarations of dependent
  // template friends.
  break;
}
}

// Defer calling `setPure` until merging above has guaranteed we've set
// `DefinitionData` (as this will need to access it).
FD->setPure(Pure);

// Read in the parameters.
unsigned NumParams = Record.readInt();
SmallVector<ParmVarDecl *, 16> Params;
Params.reserve(NumParams);
for (unsigned I = 0; I != NumParams; ++I)
  Params.push_back(readDeclAs<ParmVarDecl>());
FD->setParams(Reader.getContext(), Params);
1034}

1036void ASTDeclReader::VisitObjCMethodDecl(ObjCMethodDecl *MD) {
VisitNamedDecl(MD);
if (Record.readInt()) {
  // Load the body on-demand. Most clients won't care, because method
  // definitions rarely show up in headers.
  Reader.PendingBodies[MD] = GetCurrentCursorOffset();
  HasPendingBody = true;
}
MD->setSelfDecl(readDeclAs<ImplicitParamDecl>());
MD->setCmdDecl(readDeclAs<ImplicitParamDecl>());
MD->setInstanceMethod(Record.readInt());
MD->setVariadic(Record.readInt());
MD->setPropertyAccessor(Record.readInt());
MD->setSynthesizedAccessorStub(Record.readInt());
MD->setDefined(Record.readInt());
MD->setOverriding(Record.readInt());
MD->setHasSkippedBody(Record.readInt());

MD->setIsRedeclaration(Record.readInt());
MD->setHasRedeclaration(Record.readInt());
if (MD->hasRedeclaration())
  Reader.getContext().setObjCMethodRedeclaration(MD,
                                     readDeclAs<ObjCMethodDecl>());

MD->setDeclImplementation((ObjCMethodDecl::ImplementationControl)Record.readInt());
MD->setObjCDeclQualifier((Decl::ObjCDeclQualifier)Record.readInt());
MD->setRelatedResultType(Record.readInt());
MD->setReturnType(Record.readType());
MD->setReturnTypeSourceInfo(readTypeSourceInfo());
MD->DeclEndLoc = readSourceLocation();
unsigned NumParams = Record.readInt();
SmallVector<ParmVarDecl *, 16> Params;
Params.reserve(NumParams);
for (unsigned I = 0; I != NumParams; ++I)
  Params.push_back(readDeclAs<ParmVarDecl>());

MD->setSelLocsKind((SelectorLocationsKind)Record.readInt());
unsigned NumStoredSelLocs = Record.readInt();
SmallVector<SourceLocation, 16> SelLocs;
SelLocs.reserve(NumStoredSelLocs);
for (unsigned i = 0; i != NumStoredSelLocs; ++i)
  SelLocs.push_back(readSourceLocation());

MD->setParamsAndSelLocs(Reader.getContext(), Params, SelLocs);
1080}

1082void ASTDeclReader::VisitObjCTypeParamDecl(ObjCTypeParamDecl *D) {
VisitTypedefNameDecl(D);

D->Variance = Record.readInt();
D->Index = Record.readInt();
D->VarianceLoc = readSourceLocation();
D->ColonLoc = readSourceLocation();
1089}

1091void ASTDeclReader::VisitObjCContainerDecl(ObjCContainerDecl *CD) {
VisitNamedDecl(CD);
CD->setAtStartLoc(readSourceLocation());
CD->setAtEndRange(readSourceRange());
1095}

1097ObjCTypeParamList *ASTDeclReader::ReadObjCTypeParamList() {
unsigned numParams = Record.readInt();
if (numParams == 0)
  return nullptr;

SmallVector<ObjCTypeParamDecl *, 4> typeParams;
typeParams.reserve(numParams);
for (unsigned i = 0; i != numParams; ++i) {
  auto *typeParam = readDeclAs<ObjCTypeParamDecl>();
  if (!typeParam)
    return nullptr;

  typeParams.push_back(typeParam);
}

SourceLocation lAngleLoc = readSourceLocation();
SourceLocation rAngleLoc = readSourceLocation();

return ObjCTypeParamList::create(Reader.getContext(), lAngleLoc,
                                 typeParams, rAngleLoc);
1117}

1119void ASTDeclReader::ReadObjCDefinitionData(
       struct ObjCInterfaceDecl::DefinitionData &Data) {
// Read the superclass.
Data.SuperClassTInfo = readTypeSourceInfo();

Data.EndLoc = readSourceLocation();
Data.HasDesignatedInitializers = Record.readInt();

// Read the directly referenced protocols and their SourceLocations.
unsigned NumProtocols = Record.readInt();
SmallVector<ObjCProtocolDecl *, 16> Protocols;
Protocols.reserve(NumProtocols);
for (unsigned I = 0; I != NumProtocols; ++I)
  Protocols.push_back(readDeclAs<ObjCProtocolDecl>());
SmallVector<SourceLocation, 16> ProtoLocs;
ProtoLocs.reserve(NumProtocols);
for (unsigned I = 0; I != NumProtocols; ++I)
  ProtoLocs.push_back(readSourceLocation());
Data.ReferencedProtocols.set(Protocols.data(), NumProtocols, ProtoLocs.data(),
                             Reader.getContext());

// Read the transitive closure of protocols referenced by this class.
NumProtocols = Record.readInt();
Protocols.clear();
Protocols.reserve(NumProtocols);
for (unsigned I = 0; I != NumProtocols; ++I)
  Protocols.push_back(readDeclAs<ObjCProtocolDecl>());
Data.AllReferencedProtocols.set(Protocols.data(), NumProtocols,
                                Reader.getContext());
1148}

1150void ASTDeclReader::MergeDefinitionData(ObjCInterfaceDecl *D,
       struct ObjCInterfaceDecl::DefinitionData &&NewDD) {
// FIXME: odr checking?
1153}

1155void ASTDeclReader::VisitObjCInterfaceDecl(ObjCInterfaceDecl *ID) {
RedeclarableResult Redecl = VisitRedeclarable(ID);
VisitObjCContainerDecl(ID);
DeferredTypeID = Record.getGlobalTypeID(Record.readInt());
mergeRedeclarable(ID, Redecl);

ID->TypeParamList = ReadObjCTypeParamList();
if (Record.readInt()) {
  // Read the definition.
  ID->allocateDefinitionData();

  ReadObjCDefinitionData(ID->data());
  ObjCInterfaceDecl *Canon = ID->getCanonicalDecl();
  if (Canon->Data.getPointer()) {
    // If we already have a definition, keep the definition invariant and
    // merge the data.
    MergeDefinitionData(Canon, std::move(ID->data()));
    ID->Data = Canon->Data;
  } else {
    // Set the definition data of the canonical declaration, so other
    // redeclarations will see it.
    ID->getCanonicalDecl()->Data = ID->Data;

    // We will rebuild this list lazily.
    ID->setIvarList(nullptr);
  }

  // Note that we have deserialized a definition.
  Reader.PendingDefinitions.insert(ID);

  // Note that we've loaded this Objective-C class.
  Reader.ObjCClassesLoaded.push_back(ID);
} else {
  ID->Data = ID->getCanonicalDecl()->Data;
}
1190}

1192void ASTDeclReader::VisitObjCIvarDecl(ObjCIvarDecl *IVD) {
VisitFieldDecl(IVD);
IVD->setAccessControl((ObjCIvarDecl::AccessControl)Record.readInt());
// This field will be built lazily.
IVD->setNextIvar(nullptr);
bool synth = Record.readInt();
IVD->setSynthesize(synth);
1199}

1201void ASTDeclReader::ReadObjCDefinitionData(
       struct ObjCProtocolDecl::DefinitionData &Data) {
  unsigned NumProtoRefs = Record.readInt();
  SmallVector<ObjCProtocolDecl *, 16> ProtoRefs;
  ProtoRefs.reserve(NumProtoRefs);
  for (unsigned I = 0; I != NumProtoRefs; ++I)
    ProtoRefs.push_back(readDeclAs<ObjCProtocolDecl>());
  SmallVector<SourceLocation, 16> ProtoLocs;
  ProtoLocs.reserve(NumProtoRefs);
  for (unsigned I = 0; I != NumProtoRefs; ++I)
    ProtoLocs.push_back(readSourceLocation());
  Data.ReferencedProtocols.set(ProtoRefs.data(), NumProtoRefs,
                               ProtoLocs.data(), Reader.getContext());
1214}

1216void ASTDeclReader::MergeDefinitionData(ObjCProtocolDecl *D,
       struct ObjCProtocolDecl::DefinitionData &&NewDD) {
// FIXME: odr checking?
1219}

1221void ASTDeclReader::VisitObjCProtocolDecl(ObjCProtocolDecl *PD) {
RedeclarableResult Redecl = VisitRedeclarable(PD);
VisitObjCContainerDecl(PD);
mergeRedeclarable(PD, Redecl);

if (Record.readInt()) {
  // Read the definition.
  PD->allocateDefinitionData();

  ReadObjCDefinitionData(PD->data());

  ObjCProtocolDecl *Canon = PD->getCanonicalDecl();
  if (Canon->Data.getPointer()) {
    // If we already have a definition, keep the definition invariant and
    // merge the data.
    MergeDefinitionData(Canon, std::move(PD->data()));
    PD->Data = Canon->Data;
  } else {
    // Set the definition data of the canonical declaration, so other
    // redeclarations will see it.
    PD->getCanonicalDecl()->Data = PD->Data;
  }
  // Note that we have deserialized a definition.
  Reader.PendingDefinitions.insert(PD);
} else {
  PD->Data = PD->getCanonicalDecl()->Data;
}
1248}

1250void ASTDeclReader::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *FD) {
VisitFieldDecl(FD);
1252}

1254void ASTDeclReader::VisitObjCCategoryDecl(ObjCCategoryDecl *CD) {
VisitObjCContainerDecl(CD);
CD->setCategoryNameLoc(readSourceLocation());
CD->setIvarLBraceLoc(readSourceLocation());
CD->setIvarRBraceLoc(readSourceLocation());

// Note that this category has been deserialized. We do this before
// deserializing the interface declaration, so that it will consider this
/// category.
Reader.CategoriesDeserialized.insert(CD);

CD->ClassInterface = readDeclAs<ObjCInterfaceDecl>();
CD->TypeParamList = ReadObjCTypeParamList();
unsigned NumProtoRefs = Record.readInt();
SmallVector<ObjCProtocolDecl *, 16> ProtoRefs;
ProtoRefs.reserve(NumProtoRefs);
for (unsigned I = 0; I != NumProtoRefs; ++I)
  ProtoRefs.push_back(readDeclAs<ObjCProtocolDecl>());
SmallVector<SourceLocation, 16> ProtoLocs;
ProtoLocs.reserve(NumProtoRefs);
for (unsigned I = 0; I != NumProtoRefs; ++I)
  ProtoLocs.push_back(readSourceLocation());
CD->setProtocolList(ProtoRefs.data(), NumProtoRefs, ProtoLocs.data(),
                    Reader.getContext());

// Protocols in the class extension belong to the class.
if (NumProtoRefs > 0 && CD->ClassInterface && CD->IsClassExtension())
  CD->ClassInterface->mergeClassExtensionProtocolList(
      (ObjCProtocolDecl *const *)ProtoRefs.data(), NumProtoRefs,
      Reader.getContext());
1284}

1286void ASTDeclReader::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *CAD) {
VisitNamedDecl(CAD);
CAD->setClassInterface(readDeclAs<ObjCInterfaceDecl>());
1289}

1291void ASTDeclReader::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
VisitNamedDecl(D);
D->setAtLoc(readSourceLocation());
D->setLParenLoc(readSourceLocation());
QualType T = Record.readType();
TypeSourceInfo *TSI = readTypeSourceInfo();
D->setType(T, TSI);
D->setPropertyAttributes((ObjCPropertyAttribute::Kind)Record.readInt());
D->setPropertyAttributesAsWritten(
    (ObjCPropertyAttribute::Kind)Record.readInt());
D->setPropertyImplementation(
    (ObjCPropertyDecl::PropertyControl)Record.readInt());
DeclarationName GetterName = Record.readDeclarationName();
SourceLocation GetterLoc = readSourceLocation();
D->setGetterName(GetterName.getObjCSelector(), GetterLoc);
DeclarationName SetterName = Record.readDeclarationName();
SourceLocation SetterLoc = readSourceLocation();
D->setSetterName(SetterName.getObjCSelector(), SetterLoc);
D->setGetterMethodDecl(readDeclAs<ObjCMethodDecl>());
D->setSetterMethodDecl(readDeclAs<ObjCMethodDecl>());
D->setPropertyIvarDecl(readDeclAs<ObjCIvarDecl>());
1312}

1314void ASTDeclReader::VisitObjCImplDecl(ObjCImplDecl *D) {
VisitObjCContainerDecl(D);
D->setClassInterface(readDeclAs<ObjCInterfaceDecl>());
1317}

1319void ASTDeclReader::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
VisitObjCImplDecl(D);
D->CategoryNameLoc = readSourceLocation();
1322}

1324void ASTDeclReader::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
VisitObjCImplDecl(D);
D->setSuperClass(readDeclAs<ObjCInterfaceDecl>());
D->SuperLoc = readSourceLocation();
D->setIvarLBraceLoc(readSourceLocation());
D->setIvarRBraceLoc(readSourceLocation());
D->setHasNonZeroConstructors(Record.readInt());
D->setHasDestructors(Record.readInt());
D->NumIvarInitializers = Record.readInt();
if (D->NumIvarInitializers)
  D->IvarInitializers = ReadGlobalOffset();
1335}

1337void ASTDeclReader::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
VisitDecl(D);
D->setAtLoc(readSourceLocation());
D->setPropertyDecl(readDeclAs<ObjCPropertyDecl>());
D->PropertyIvarDecl = readDeclAs<ObjCIvarDecl>();
D->IvarLoc = readSourceLocation();
D->setGetterMethodDecl(readDeclAs<ObjCMethodDecl>());
D->setSetterMethodDecl(readDeclAs<ObjCMethodDecl>());
D->setGetterCXXConstructor(Record.readExpr());
D->setSetterCXXAssignment(Record.readExpr());
1347}

1349void ASTDeclReader::VisitFieldDecl(FieldDecl *FD) {
VisitDeclaratorDecl(FD);
FD->Mutable = Record.readInt();

if (auto ISK = static_cast<FieldDecl::InitStorageKind>(Record.readInt())) {
  FD->InitStorage.setInt(ISK);
  FD->InitStorage.setPointer(ISK == FieldDecl::ISK_CapturedVLAType
                                 ? Record.readType().getAsOpaquePtr()
                                 : Record.readExpr());
}

if (auto *BW = Record.readExpr())
  FD->setBitWidth(BW);

if (!FD->getDeclName()) {
  if (auto *Tmpl = readDeclAs<FieldDecl>())
    Reader.getContext().setInstantiatedFromUnnamedFieldDecl(FD, Tmpl);
}
mergeMergeable(FD);
1368}

1370void ASTDeclReader::VisitMSPropertyDecl(MSPropertyDecl *PD) {
VisitDeclaratorDecl(PD);
PD->GetterId = Record.readIdentifier();
PD->SetterId = Record.readIdentifier();
1374}

1376void ASTDeclReader::VisitMSGuidDecl(MSGuidDecl *D) {
VisitValueDecl(D);
D->PartVal.Part1 = Record.readInt();
D->PartVal.Part2 = Record.readInt();
D->PartVal.Part3 = Record.readInt();
for (auto &C : D->PartVal.Part4And5)
  C = Record.readInt();

// Add this GUID to the AST context's lookup structure, and merge if needed.
if (MSGuidDecl *Existing = Reader.getContext().MSGuidDecls.GetOrInsertNode(D))
  Reader.getContext().setPrimaryMergedDecl(D, Existing->getCanonicalDecl());
1387}

1389void ASTDeclReader::VisitTemplateParamObjectDecl(TemplateParamObjectDecl *D) {
VisitValueDecl(D);
D->Value = Record.readAPValue();

// Add this template parameter object to the AST context's lookup structure,
// and merge if needed.
if (TemplateParamObjectDecl *Existing =
        Reader.getContext().TemplateParamObjectDecls.GetOrInsertNode(D))
  Reader.getContext().setPrimaryMergedDecl(D, Existing->getCanonicalDecl());
1398}

1400void ASTDeclReader::VisitIndirectFieldDecl(IndirectFieldDecl *FD) {
VisitValueDecl(FD);

FD->ChainingSize = Record.readInt();
assert(FD->ChainingSize >= 2 && "Anonymous chaining must be >= 2")((void)0);
FD->Chaining = new (Reader.getContext())NamedDecl*[FD->ChainingSize];

for (unsigned I = 0; I != FD->ChainingSize; ++I)
  FD->Chaining[I] = readDeclAs<NamedDecl>();

mergeMergeable(FD);
1411}

1413ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
RedeclarableResult Redecl = VisitRedeclarable(VD);
VisitDeclaratorDecl(VD);

VD->VarDeclBits.SClass = (StorageClass)Record.readInt();
VD->VarDeclBits.TSCSpec = Record.readInt();
VD->VarDeclBits.InitStyle = Record.readInt();
VD->VarDeclBits.ARCPseudoStrong = Record.readInt();
if (!isa<ParmVarDecl>(VD)) {
  VD->NonParmVarDeclBits.IsThisDeclarationADemotedDefinition =
      Record.readInt();
  VD->NonParmVarDeclBits.ExceptionVar = Record.readInt();
  VD->NonParmVarDeclBits.NRVOVariable = Record.readInt();
  VD->NonParmVarDeclBits.CXXForRangeDecl = Record.readInt();
  VD->NonParmVarDeclBits.ObjCForDecl = Record.readInt();
  VD->NonParmVarDeclBits.IsInline = Record.readInt();
  VD->NonParmVarDeclBits.IsInlineSpecified = Record.readInt();
  VD->NonParmVarDeclBits.IsConstexpr = Record.readInt();
  VD->NonParmVarDeclBits.IsInitCapture = Record.readInt();
  VD->NonParmVarDeclBits.PreviousDeclInSameBlockScope = Record.readInt();
  VD->NonParmVarDeclBits.ImplicitParamKind = Record.readInt();
  VD->NonParmVarDeclBits.EscapingByref = Record.readInt();
}
auto VarLinkage = Linkage(Record.readInt());
VD->setCachedLinkage(VarLinkage);

// Reconstruct the one piece of the IdentifierNamespace that we need.
if (VD->getStorageClass() == SC_Extern && VarLinkage != NoLinkage &&
    VD->getLexicalDeclContext()->isFunctionOrMethod())
  VD->setLocalExternDecl();

if (uint64_t Val = Record.readInt()) {
  VD->setInit(Record.readExpr());
  if (Val != 1) {
    EvaluatedStmt *Eval = VD->ensureEvaluatedStmt();
    Eval->HasConstantInitialization = (Val & 2) != 0;
    Eval->HasConstantDestruction = (Val & 4) != 0;
  }
}

if (VD->hasAttr<BlocksAttr>() && VD->getType()->getAsCXXRecordDecl()) {
  Expr *CopyExpr = Record.readExpr();
  if (CopyExpr)
    Reader.getContext().setBlockVarCopyInit(VD, CopyExpr, Record.readInt());
}

if (VD->getStorageDuration() == SD_Static && Record.readInt()) {
  Reader.DefinitionSource[VD] =
      Loc.F->Kind == ModuleKind::MK_MainFile ||
      Reader.getContext().getLangOpts().BuildingPCHWithObjectFile;
}

enum VarKind {
  VarNotTemplate = 0, VarTemplate, StaticDataMemberSpecialization
};
switch ((VarKind)Record.readInt()) {
case VarNotTemplate:
  // Only true variables (not parameters or implicit parameters) can be
  // merged; the other kinds are not really redeclarable at all.
  if (!isa<ParmVarDecl>(VD) && !isa<ImplicitParamDecl>(VD) &&
      !isa<VarTemplateSpecializationDecl>(VD))
    mergeRedeclarable(VD, Redecl);
  break;
case VarTemplate:
  // Merged when we merge the template.
  VD->setDescribedVarTemplate(readDeclAs<VarTemplateDecl>());
  break;
case StaticDataMemberSpecialization: { // HasMemberSpecializationInfo.
  auto *Tmpl = readDeclAs<VarDecl>();
  auto TSK = (TemplateSpecializationKind)Record.readInt();
  SourceLocation POI = readSourceLocation();
  Reader.getContext().setInstantiatedFromStaticDataMember(VD, Tmpl, TSK,POI);
  mergeRedeclarable(VD, Redecl);
  break;
}
}

return Redecl;
1491}

1493void ASTDeclReader::VisitImplicitParamDecl(ImplicitParamDecl *PD) {
VisitVarDecl(PD);
1495}

1497void ASTDeclReader::VisitParmVarDecl(ParmVarDecl *PD) {
VisitVarDecl(PD);
unsigned isObjCMethodParam = Record.readInt();
unsigned scopeDepth = Record.readInt();
unsigned scopeIndex = Record.readInt();
unsigned declQualifier = Record.readInt();
if (isObjCMethodParam) {
  assert(scopeDepth == 0)((void)0);
  PD->setObjCMethodScopeInfo(scopeIndex);
  PD->ParmVarDeclBits.ScopeDepthOrObjCQuals = declQualifier;
} else {
  PD->setScopeInfo(scopeDepth, scopeIndex);
}
PD->ParmVarDeclBits.IsKNRPromoted = Record.readInt();
PD->ParmVarDeclBits.HasInheritedDefaultArg = Record.readInt();
if (Record.readInt()) // hasUninstantiatedDefaultArg.
  PD->setUninstantiatedDefaultArg(Record.readExpr());

// FIXME: If this is a redeclaration of a function from another module, handle
// inheritance of default arguments.
1517}

1519void ASTDeclReader::VisitDecompositionDecl(DecompositionDecl *DD) {
VisitVarDecl(DD);
auto **BDs = DD->getTrailingObjects<BindingDecl *>();
for (unsigned I = 0; I != DD->NumBindings; ++I) {
  BDs[I] = readDeclAs<BindingDecl>();
  BDs[I]->setDecomposedDecl(DD);
}
1526}

1528void ASTDeclReader::VisitBindingDecl(BindingDecl *BD) {
VisitValueDecl(BD);
BD->Binding = Record.readExpr();
1531}

1533void ASTDeclReader::VisitFileScopeAsmDecl(FileScopeAsmDecl *AD) {
VisitDecl(AD);
AD->setAsmString(cast<StringLiteral>(Record.readExpr()));
AD->setRParenLoc(readSourceLocation());
1537}

1539void ASTDeclReader::VisitBlockDecl(BlockDecl *BD) {
VisitDecl(BD);
BD->setBody(cast_or_null<CompoundStmt>(Record.readStmt()));
BD->setSignatureAsWritten(readTypeSourceInfo());
unsigned NumParams = Record.readInt();
SmallVector<ParmVarDecl *, 16> Params;
Params.reserve(NumParams);
for (unsigned I = 0; I != NumParams; ++I)
  Params.push_back(readDeclAs<ParmVarDecl>());
BD->setParams(Params);

BD->setIsVariadic(Record.readInt());
BD->setBlockMissingReturnType(Record.readInt());
BD->setIsConversionFromLambda(Record.readInt());
BD->setDoesNotEscape(Record.readInt());
BD->setCanAvoidCopyToHeap(Record.readInt());

bool capturesCXXThis = Record.readInt();
unsigned numCaptures = Record.readInt();
SmallVector<BlockDecl::Capture, 16> captures;
captures.reserve(numCaptures);
for (unsigned i = 0; i != numCaptures; ++i) {
  auto *decl = readDeclAs<VarDecl>();
  unsigned flags = Record.readInt();
  bool byRef = (flags & 1);
  bool nested = (flags & 2);
  Expr *copyExpr = ((flags & 4) ? Record.readExpr() : nullptr);

  captures.push_back(BlockDecl::Capture(decl, byRef, nested, copyExpr));
}
BD->setCaptures(Reader.getContext(), captures, capturesCXXThis);
1570}

1572void ASTDeclReader::VisitCapturedDecl(CapturedDecl *CD) {
VisitDecl(CD);
unsigned ContextParamPos = Record.readInt();
CD->setNothrow(Record.readInt() != 0);
// Body is set by VisitCapturedStmt.
for (unsigned I = 0; I < CD->NumParams; ++I) {
  if (I != ContextParamPos)
    CD->setParam(I, readDeclAs<ImplicitParamDecl>());
  else
    CD->setContextParam(I, readDeclAs<ImplicitParamDecl>());
}
1583}

1585void ASTDeclReader::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
VisitDecl(D);
D->setLanguage((LinkageSpecDecl::LanguageIDs)Record.readInt());
D->setExternLoc(readSourceLocation());
D->setRBraceLoc(readSourceLocation());
1590}

1592void ASTDeclReader::VisitExportDecl(ExportDecl *D) {
VisitDecl(D);
D->RBraceLoc = readSourceLocation();
1595}

1597void ASTDeclReader::VisitLabelDecl(LabelDecl *D) {
VisitNamedDecl(D);
D->setLocStart(readSourceLocation());
1600}

1602void ASTDeclReader::VisitNamespaceDecl(NamespaceDecl *D) {
RedeclarableResult Redecl = VisitRedeclarable(D);
1
Calling 'ASTDeclReader::VisitRedeclarable'→
VisitNamedDecl(D);
D->setInline(Record.readInt());
D->LocStart = readSourceLocation();
D->RBraceLoc = readSourceLocation();

// Defer loading the anonymous namespace until we've finished merging
// this namespace; loading it might load a later declaration of the
// same namespace, and we have an invariant that older declarations
// get merged before newer ones try to merge.
GlobalDeclID AnonNamespace = 0;
if (Redecl.getFirstID() == ThisDeclID) {
  AnonNamespace = readDeclID();
} else {
  // Link this namespace back to the first declaration, which has already
  // been deserialized.
  D->AnonOrFirstNamespaceAndInline.setPointer(D->getFirstDecl());
}

mergeRedeclarable(D, Redecl);

if (AnonNamespace) {
  // Each module has its own anonymous namespace, which is disjoint from
  // any other module's anonymous namespaces, so don't attach the anonymous
  // namespace at all.
  auto *Anon = cast<NamespaceDecl>(Reader.GetDecl(AnonNamespace));
  if (!Record.isModule())
    D->setAnonymousNamespace(Anon);
}
1632}

1634void ASTDeclReader::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
RedeclarableResult Redecl = VisitRedeclarable(D);
VisitNamedDecl(D);
D->NamespaceLoc = readSourceLocation();
D->IdentLoc = readSourceLocation();
D->QualifierLoc = Record.readNestedNameSpecifierLoc();
D->Namespace = readDeclAs<NamedDecl>();
mergeRedeclarable(D, Redecl);
1642}

1644void ASTDeclReader::VisitUsingDecl(UsingDecl *D) {
VisitNamedDecl(D);
D->setUsingLoc(readSourceLocation());
D->QualifierLoc = Record.readNestedNameSpecifierLoc();
D->DNLoc = Record.readDeclarationNameLoc(D->getDeclName());
D->FirstUsingShadow.setPointer(readDeclAs<UsingShadowDecl>());
D->setTypename(Record.readInt());
if (auto *Pattern = readDeclAs<NamedDecl>())
  Reader.getContext().setInstantiatedFromUsingDecl(D, Pattern);
mergeMergeable(D);
1654}

1656void ASTDeclReader::VisitUsingEnumDecl(UsingEnumDecl *D) {
VisitNamedDecl(D);
D->setUsingLoc(readSourceLocation());
D->setEnumLoc(readSourceLocation());
D->Enum = readDeclAs<EnumDecl>();
D->FirstUsingShadow.setPointer(readDeclAs<UsingShadowDecl>());
if (auto *Pattern = readDeclAs<UsingEnumDecl>())
  Reader.getContext().setInstantiatedFromUsingEnumDecl(D, Pattern);
mergeMergeable(D);
1665}

1667void ASTDeclReader::VisitUsingPackDecl(UsingPackDecl *D) {
VisitNamedDecl(D);
D->InstantiatedFrom = readDeclAs<NamedDecl>();
auto **Expansions = D->getTrailingObjects<NamedDecl *>();
for (unsigned I = 0; I != D->NumExpansions; ++I)
  Expansions[I] = readDeclAs<NamedDecl>();
mergeMergeable(D);
1674}

1676void ASTDeclReader::VisitUsingShadowDecl(UsingShadowDecl *D) {
RedeclarableResult Redecl = VisitRedeclarable(D);
VisitNamedDecl(D);
D->Underlying = readDeclAs<NamedDecl>();
D->IdentifierNamespace = Record.readInt();
D->UsingOrNextShadow = readDeclAs<NamedDecl>();
auto *Pattern = readDeclAs<UsingShadowDecl>();
if (Pattern)
  Reader.getContext().setInstantiatedFromUsingShadowDecl(D, Pattern);
mergeRedeclarable(D, Redecl);
1686}

1688void ASTDeclReader::VisitConstructorUsingShadowDecl(
  ConstructorUsingShadowDecl *D) {
VisitUsingShadowDecl(D);
D->NominatedBaseClassShadowDecl = readDeclAs<ConstructorUsingShadowDecl>();
D->ConstructedBaseClassShadowDecl = readDeclAs<ConstructorUsingShadowDecl>();
D->IsVirtual = Record.readInt();
1694}

1696void ASTDeclReader::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
VisitNamedDecl(D);
D->UsingLoc = readSourceLocation();
D->NamespaceLoc = readSourceLocation();
D->QualifierLoc = Record.readNestedNameSpecifierLoc();
D->NominatedNamespace = readDeclAs<NamedDecl>();
D->CommonAncestor = readDeclAs<DeclContext>();
1703}

1705void ASTDeclReader::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
VisitValueDecl(D);
D->setUsingLoc(readSourceLocation());
D->QualifierLoc = Record.readNestedNameSpecifierLoc();
D->DNLoc = Record.readDeclarationNameLoc(D->getDeclName());
D->EllipsisLoc = readSourceLocation();
mergeMergeable(D);
1712}

1714void ASTDeclReader::VisitUnresolvedUsingTypenameDecl(
                                             UnresolvedUsingTypenameDecl *D) {
VisitTypeDecl(D);
D->TypenameLocation = readSourceLocation();
D->QualifierLoc = Record.readNestedNameSpecifierLoc();
D->EllipsisLoc = readSourceLocation();
mergeMergeable(D);
1721}

1723void ASTDeclReader::VisitUnresolvedUsingIfExistsDecl(
  UnresolvedUsingIfExistsDecl *D) {
VisitNamedDecl(D);
1726}

1728void ASTDeclReader::ReadCXXDefinitionData(
  struct CXXRecordDecl::DefinitionData &Data, const CXXRecordDecl *D) {
#define FIELD(Name, Width, Merge) \
Data.Name = Record.readInt();
#include "clang/AST/CXXRecordDeclDefinitionBits.def"

// Note: the caller has deserialized the IsLambda bit already.
Data.ODRHash = Record.readInt();
Data.HasODRHash = true;

if (Record.readInt()) {
  Reader.DefinitionSource[D] = 
      Loc.F->Kind == ModuleKind::MK_MainFile ||
      Reader.getContext().getLangOpts().BuildingPCHWithObjectFile;
}

Data.NumBases = Record.readInt();
if (Data.NumBases)
  Data.Bases = ReadGlobalOffset();
Data.NumVBases = Record.readInt();
if (Data.NumVBases)
  Data.VBases = ReadGlobalOffset();

Record.readUnresolvedSet(Data.Conversions);
Data.ComputedVisibleConversions = Record.readInt();
if (Data.ComputedVisibleConversions)
  Record.readUnresolvedSet(Data.VisibleConversions);
assert(Data.Definition && "Data.Definition should be already set!")((void)0);
Data.FirstFriend = readDeclID();

if (Data.IsLambda) {
  using Capture = LambdaCapture;

  auto &Lambda = static_cast<CXXRecordDecl::LambdaDefinitionData &>(Data);
  Lambda.Dependent = Record.readInt();
  Lambda.IsGenericLambda = Record.readInt();
  Lambda.CaptureDefault = Record.readInt();
  Lambda.NumCaptures = Record.readInt();
  Lambda.NumExplicitCaptures = Record.readInt();
  Lambda.HasKnownInternalLinkage = Record.readInt();
  Lambda.ManglingNumber = Record.readInt();
  D->setDeviceLambdaManglingNumber(Record.readInt());
  Lambda.ContextDecl = readDeclID();
  Lambda.Captures = (Capture *)Reader.getContext().Allocate(
      sizeof(Capture) * Lambda.NumCaptures);
  Capture *ToCapture = Lambda.Captures;
  Lambda.MethodTyInfo = readTypeSourceInfo();
  for (unsigned I = 0, N = Lambda.NumCaptures; I != N; ++I) {
    SourceLocation Loc = readSourceLocation();
    bool IsImplicit = Record.readInt();
    auto Kind = static_cast<LambdaCaptureKind>(Record.readInt());
    switch (Kind) {
    case LCK_StarThis:
    case LCK_This:
    case LCK_VLAType:
      *ToCapture++ = Capture(Loc, IsImplicit, Kind, nullptr,SourceLocation());
      break;
    case LCK_ByCopy:
    case LCK_ByRef:
      auto *Var = readDeclAs<VarDecl>();
      SourceLocation EllipsisLoc = readSourceLocation();
      *ToCapture++ = Capture(Loc, IsImplicit, Kind, Var, EllipsisLoc);
      break;
    }
  }
}
1794}

1796void ASTDeclReader::MergeDefinitionData(
  CXXRecordDecl *D, struct CXXRecordDecl::DefinitionData &&MergeDD) {
assert(D->DefinitionData &&((void)0)
       "merging class definition into non-definition")((void)0);
auto &DD = *D->DefinitionData;

if (DD.Definition != MergeDD.Definition) {
  // Track that we merged the definitions.
  Reader.MergedDeclContexts.insert(std::make_pair(MergeDD.Definition,
                                                  DD.Definition));
  Reader.PendingDefinitions.erase(MergeDD.Definition);
  MergeDD.Definition->setCompleteDefinition(false);
  Reader.mergeDefinitionVisibility(DD.Definition, MergeDD.Definition);
  assert(Reader.Lookups.find(MergeDD.Definition) == Reader.Lookups.end() &&((void)0)
         "already loaded pending lookups for merged definition")((void)0);
}

auto PFDI = Reader.PendingFakeDefinitionData.find(&DD);
if (PFDI != Reader.PendingFakeDefinitionData.end() &&
    PFDI->second == ASTReader::PendingFakeDefinitionKind::Fake) {
  // We faked up this definition data because we found a class for which we'd
  // not yet loaded the definition. Replace it with the real thing now.
  assert(!DD.IsLambda && !MergeDD.IsLambda && "faked up lambda definition?")((void)0);
  PFDI->second = ASTReader::PendingFakeDefinitionKind::FakeLoaded;

  // Don't change which declaration is the definition; that is required
  // to be invariant once we select it.
  auto *Def = DD.Definition;
  DD = std::move(MergeDD);
  DD.Definition = Def;
  return;
}

bool DetectedOdrViolation = false;

#define FIELD(Name, Width, Merge) Merge(Name)
#define MERGE_OR(Field) DD.Field |= MergeDD.Field;
#define NO_MERGE(Field) \
  DetectedOdrViolation |= DD.Field != MergeDD.Field; \
  MERGE_OR(Field)
#include "clang/AST/CXXRecordDeclDefinitionBits.def"
NO_MERGE(IsLambda)
#undef NO_MERGE
#undef MERGE_OR

if (DD.NumBases != MergeDD.NumBases || DD.NumVBases != MergeDD.NumVBases)
  DetectedOdrViolation = true;
// FIXME: Issue a diagnostic if the base classes don't match when we come
// to lazily load them.

// FIXME: Issue a diagnostic if the list of conversion functions doesn't
// match when we come to lazily load them.
if (MergeDD.ComputedVisibleConversions && !DD.ComputedVisibleConversions) {
  DD.VisibleConversions = std::move(MergeDD.VisibleConversions);
  DD.ComputedVisibleConversions = true;
}

// FIXME: Issue a diagnostic if FirstFriend doesn't match when we come to
// lazily load it.

if (DD.IsLambda) {
  // FIXME: ODR-checking for merging lambdas (this happens, for instance,
  // when they occur within the body of a function template specialization).
}

if (D->getODRHash() != MergeDD.ODRHash) {
  DetectedOdrViolation = true;
}

if (DetectedOdrViolation)
  Reader.PendingOdrMergeFailures[DD.Definition].push_back(
      {MergeDD.Definition, &MergeDD});
1868}

1870void ASTDeclReader::ReadCXXRecordDefinition(CXXRecordDecl *D, bool Update) {
struct CXXRecordDecl::DefinitionData *DD;
ASTContext &C = Reader.getContext();

// Determine whether this is a lambda closure type, so that we can
// allocate the appropriate DefinitionData structure.
bool IsLambda = Record.readInt();
if (IsLambda)
  DD = new (C) CXXRecordDecl::LambdaDefinitionData(D, nullptr, false, false,
                                                   LCD_None);
else
  DD = new (C) struct CXXRecordDecl::DefinitionData(D);

CXXRecordDecl *Canon = D->getCanonicalDecl();
// Set decl definition data before reading it, so that during deserialization
// when we read CXXRecordDecl, it already has definition data and we don't
// set fake one.
if (!Canon->DefinitionData)
  Canon->DefinitionData = DD;
D->DefinitionData = Canon->DefinitionData;
ReadCXXDefinitionData(*DD, D);

// We might already have a different definition for this record. This can
// happen either because we're reading an update record, or because we've
// already done some merging. Either way, just merge into it.
if (Canon->DefinitionData != DD) {
  MergeDefinitionData(Canon, std::move(*DD));
  return;
}

// Mark this declaration as being a definition.
D->setCompleteDefinition(true);

// If this is not the first declaration or is an update record, we can have
// other redeclarations already. Make a note that we need to propagate the
// DefinitionData pointer onto them.
if (Update || Canon != D)
  Reader.PendingDefinitions.insert(D);
1908}

1910ASTDeclReader::RedeclarableResult
1911ASTDeclReader::VisitCXXRecordDeclImpl(CXXRecordDecl *D) {
RedeclarableResult Redecl = VisitRecordDeclImpl(D);

ASTContext &C = Reader.getContext();

enum CXXRecKind {
  CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
};
switch ((CXXRecKind)Record.readInt()) {
case CXXRecNotTemplate:
  // Merged when we merge the folding set entry in the primary template.
  if (!isa<ClassTemplateSpecializationDecl>(D))
    mergeRedeclarable(D, Redecl);
  break;
case CXXRecTemplate: {
  // Merged when we merge the template.
  auto *Template = readDeclAs<ClassTemplateDecl>();
  D->TemplateOrInstantiation = Template;
  if (!Template->getTemplatedDecl()) {
    // We've not actually loaded the ClassTemplateDecl yet, because we're
    // currently being loaded as its pattern. Rely on it to set up our
    // TypeForDecl (see VisitClassTemplateDecl).
    //
    // Beware: we do not yet know our canonical declaration, and may still
    // get merged once the surrounding class template has got off the ground.
    DeferredTypeID = 0;
  }
  break;
}
case CXXRecMemberSpecialization: {
  auto *RD = readDeclAs<CXXRecordDecl>();
  auto TSK = (TemplateSpecializationKind)Record.readInt();
  SourceLocation POI = readSourceLocation();
  MemberSpecializationInfo *MSI = new (C) MemberSpecializationInfo(RD, TSK);
  MSI->setPointOfInstantiation(POI);
  D->TemplateOrInstantiation = MSI;
  mergeRedeclarable(D, Redecl);
  break;
}
}

bool WasDefinition = Record.readInt();
if (WasDefinition)
  ReadCXXRecordDefinition(D, /*Update*/false);
else
  // Propagate DefinitionData pointer from the canonical declaration.
  D->DefinitionData = D->getCanonicalDecl()->DefinitionData;

// Lazily load the key function to avoid deserializing every method so we can
// compute it.
if (WasDefinition) {
  DeclID KeyFn = readDeclID();
  if (KeyFn && D->isCompleteDefinition())
    // FIXME: This is wrong for the ARM ABI, where some other module may have
    // made this function no longer be a key function. We need an update
    // record or similar for that case.
    C.KeyFunctions[D] = KeyFn;
}

return Redecl;
1971}

1973void ASTDeclReader::VisitCXXDeductionGuideDecl(CXXDeductionGuideDecl *D) {
D->setExplicitSpecifier(Record.readExplicitSpec());
D->Ctor = readDeclAs<CXXConstructorDecl>();
VisitFunctionDecl(D);
D->setIsCopyDeductionCandidate(Record.readInt());
1978}

1980void ASTDeclReader::VisitCXXMethodDecl(CXXMethodDecl *D) {
VisitFunctionDecl(D);

unsigned NumOverridenMethods = Record.readInt();
if (D->isCanonicalDecl()) {
  while (NumOverridenMethods--) {
    // Avoid invariant checking of CXXMethodDecl::addOverriddenMethod,
    // MD may be initializing.
    if (auto *MD = readDeclAs<CXXMethodDecl>())
      Reader.getContext().addOverriddenMethod(D, MD->getCanonicalDecl());
  }
} else {
  // We don't care about which declarations this used to override; we get
  // the relevant information from the canonical declaration.
  Record.skipInts(NumOverridenMethods);
}
1996}

1998void ASTDeclReader::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
// We need the inherited constructor information to merge the declaration,
// so we have to read it before we call VisitCXXMethodDecl.
D->setExplicitSpecifier(Record.readExplicitSpec());
if (D->isInheritingConstructor()) {
  auto *Shadow = readDeclAs<ConstructorUsingShadowDecl>();
  auto *Ctor = readDeclAs<CXXConstructorDecl>();
  *D->getTrailingObjects<InheritedConstructor>() =
      InheritedConstructor(Shadow, Ctor);
}

VisitCXXMethodDecl(D);
2010}

2012void ASTDeclReader::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
VisitCXXMethodDecl(D);

if (auto *OperatorDelete = readDeclAs<FunctionDecl>()) {
  CXXDestructorDecl *Canon = D->getCanonicalDecl();
  auto *ThisArg = Record.readExpr();
  // FIXME: Check consistency if we have an old and new operator delete.
  if (!Canon->OperatorDelete) {
    Canon->OperatorDelete = OperatorDelete;
    Canon->OperatorDeleteThisArg = ThisArg;
  }
}
2024}

2026void ASTDeclReader::VisitCXXConversionDecl(CXXConversionDecl *D) {
D->setExplicitSpecifier(Record.readExplicitSpec());
VisitCXXMethodDecl(D);
2029}

2031void ASTDeclReader::VisitImportDecl(ImportDecl *D) {
VisitDecl(D);
D->ImportedModule = readModule();
D->setImportComplete(Record.readInt());
auto *StoredLocs = D->getTrailingObjects<SourceLocation>();
for (unsigned I = 0, N = Record.back(); I != N; ++I)
  StoredLocs[I] = readSourceLocation();
Record.skipInts(1); // The number of stored source locations.
2039}

2041void ASTDeclReader::VisitAccessSpecDecl(AccessSpecDecl *D) {
VisitDecl(D);
D->setColonLoc(readSourceLocation());
2044}

2046void ASTDeclReader::VisitFriendDecl(FriendDecl *D) {
VisitDecl(D);
if (Record.readInt()) // hasFriendDecl
  D->Friend = readDeclAs<NamedDecl>();
else
  D->Friend = readTypeSourceInfo();
for (unsigned i = 0; i != D->NumTPLists; ++i)
  D->getTrailingObjects<TemplateParameterList *>()[i] =
      Record.readTemplateParameterList();
D->NextFriend = readDeclID();
D->UnsupportedFriend = (Record.readInt() != 0);
D->FriendLoc = readSourceLocation();
2058}

2060void ASTDeclReader::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
VisitDecl(D);
unsigned NumParams = Record.readInt();
D->NumParams = NumParams;
D->Params = new TemplateParameterList*[NumParams];
for (unsigned i = 0; i != NumParams; ++i)
  D->Params[i] = Record.readTemplateParameterList();
if (Record.readInt()) // HasFriendDecl
  D->Friend = readDeclAs<NamedDecl>();
else
  D->Friend = readTypeSourceInfo();
D->FriendLoc = readSourceLocation();
2072}

2074DeclID ASTDeclReader::VisitTemplateDecl(TemplateDecl *D) {
VisitNamedDecl(D);

DeclID PatternID = readDeclID();
auto *TemplatedDecl = cast_or_null<NamedDecl>(Reader.GetDecl(PatternID));
TemplateParameterList *TemplateParams = Record.readTemplateParameterList();
D->init(TemplatedDecl, TemplateParams);

return PatternID;
2083}

2085void ASTDeclReader::VisitConceptDecl(ConceptDecl *D) {
VisitTemplateDecl(D);
D->ConstraintExpr = Record.readExpr();
mergeMergeable(D);
2089}

2091void ASTDeclReader::VisitRequiresExprBodyDecl(RequiresExprBodyDecl *D) {
2092}

2094ASTDeclReader::RedeclarableResult
2095ASTDeclReader::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
RedeclarableResult Redecl = VisitRedeclarable(D);

// Make sure we've allocated the Common pointer first. We do this before
// VisitTemplateDecl so that getCommonPtr() can be used during initialization.
RedeclarableTemplateDecl *CanonD = D->getCanonicalDecl();
if (!CanonD->Common) {
  CanonD->Common = CanonD->newCommon(Reader.getContext());
  Reader.PendingDefinitions.insert(CanonD);
}
D->Common = CanonD->Common;

// If this is the first declaration of the template, fill in the information
// for the 'common' pointer.
if (ThisDeclID == Redecl.getFirstID()) {
  if (auto *RTD = readDeclAs<RedeclarableTemplateDecl>()) {
    assert(RTD->getKind() == D->getKind() &&((void)0)
           "InstantiatedFromMemberTemplate kind mismatch")((void)0);
    D->setInstantiatedFromMemberTemplate(RTD);
    if (Record.readInt())
      D->setMemberSpecialization();
  }
}

DeclID PatternID = VisitTemplateDecl(D);
D->IdentifierNamespace = Record.readInt();

mergeRedeclarable(D, Redecl, PatternID);

// If we merged the template with a prior declaration chain, merge the common
// pointer.
// FIXME: Actually merge here, don't just overwrite.
D->Common = D->getCanonicalDecl()->Common;

return Redecl;
2130}

2132void ASTDeclReader::VisitClassTemplateDecl(ClassTemplateDecl *D) {
RedeclarableResult Redecl = VisitRedeclarableTemplateDecl(D);

if (ThisDeclID == Redecl.getFirstID()) {
  // This ClassTemplateDecl owns a CommonPtr; read it to keep track of all of
  // the specializations.
  SmallVector<serialization::DeclID, 32> SpecIDs;
  readDeclIDList(SpecIDs);
  ASTDeclReader::AddLazySpecializations(D, SpecIDs);
}

if (D->getTemplatedDecl()->TemplateOrInstantiation) {
  // We were loaded before our templated declaration was. We've not set up
  // its corresponding type yet (see VisitCXXRecordDeclImpl), so reconstruct
  // it now.
  Reader.getContext().getInjectedClassNameType(
      D->getTemplatedDecl(), D->getInjectedClassNameSpecialization());
}
2150}

2152void ASTDeclReader::VisitBuiltinTemplateDecl(BuiltinTemplateDecl *D) {
llvm_unreachable("BuiltinTemplates are not serialized")__builtin_unreachable();
2154}

2156/// TODO: Unify with ClassTemplateDecl version?
2157///       May require unifying ClassTemplateDecl and
2158///        VarTemplateDecl beyond TemplateDecl...
2159void ASTDeclReader::VisitVarTemplateDecl(VarTemplateDecl *D) {
RedeclarableResult Redecl = VisitRedeclarableTemplateDecl(D);

if (ThisDeclID == Redecl.getFirstID()) {
  // This VarTemplateDecl owns a CommonPtr; read it to keep track of all of
  // the specializations.
  SmallVector<serialization::DeclID, 32> SpecIDs;
  readDeclIDList(SpecIDs);
  ASTDeclReader::AddLazySpecializations(D, SpecIDs);
}
2169}

2171ASTDeclReader::RedeclarableResult
2172ASTDeclReader::VisitClassTemplateSpecializationDeclImpl(
  ClassTemplateSpecializationDecl *D) {
RedeclarableResult Redecl = VisitCXXRecordDeclImpl(D);

ASTContext &C = Reader.getContext();
if (Decl *InstD = readDecl()) {
  if (auto *CTD = dyn_cast<ClassTemplateDecl>(InstD)) {
    D->SpecializedTemplate = CTD;
  } else {
    SmallVector<TemplateArgument, 8> TemplArgs;
    Record.readTemplateArgumentList(TemplArgs);
    TemplateArgumentList *ArgList
      = TemplateArgumentList::CreateCopy(C, TemplArgs);
    auto *PS =
        new (C) ClassTemplateSpecializationDecl::
                                           SpecializedPartialSpecialization();
    PS->PartialSpecialization
        = cast<ClassTemplatePartialSpecializationDecl>(InstD);
    PS->TemplateArgs = ArgList;
    D->SpecializedTemplate = PS;
  }
}

SmallVector<TemplateArgument, 8> TemplArgs;
Record.readTemplateArgumentList(TemplArgs, /*Canonicalize*/ true);
D->TemplateArgs = TemplateArgumentList::CreateCopy(C, TemplArgs);
D->PointOfInstantiation = readSourceLocation();
D->SpecializationKind = (TemplateSpecializationKind)Record.readInt();

bool writtenAsCanonicalDecl = Record.readInt();
if (writtenAsCanonicalDecl) {
  auto *CanonPattern = readDeclAs<ClassTemplateDecl>();
  if (D->isCanonicalDecl()) { // It's kept in the folding set.
    // Set this as, or find, the canonical declaration for this specialization
    ClassTemplateSpecializationDecl *CanonSpec;
    if (auto *Partial = dyn_cast<ClassTemplatePartialSpecializationDecl>(D)) {
      CanonSpec = CanonPattern->getCommonPtr()->PartialSpecializations
          .GetOrInsertNode(Partial);
    } else {
      CanonSpec =
          CanonPattern->getCommonPtr()->Specializations.GetOrInsertNode(D);
    }
    // If there was already a canonical specialization, merge into it.
    if (CanonSpec != D) {
      mergeRedeclarable<TagDecl>(D, CanonSpec, Redecl);

      // This declaration might be a definition. Merge with any existing
      // definition.
      if (auto *DDD = D->DefinitionData) {
        if (CanonSpec->DefinitionData)
          MergeDefinitionData(CanonSpec, std::move(*DDD));
        else
          CanonSpec->DefinitionData = D->DefinitionData;
      }
      D->DefinitionData = CanonSpec->DefinitionData;
    }
  }
}

// Explicit info.
if (TypeSourceInfo *TyInfo = readTypeSourceInfo()) {
  auto *ExplicitInfo =
      new (C) ClassTemplateSpecializationDecl::ExplicitSpecializationInfo;
  ExplicitInfo->TypeAsWritten = TyInfo;
  ExplicitInfo->ExternLoc = readSourceLocation();
  ExplicitInfo->TemplateKeywordLoc = readSourceLocation();
  D->ExplicitInfo = ExplicitInfo;
}

return Redecl;
2242}

2244void ASTDeclReader::VisitClassTemplatePartialSpecializationDecl(
                                  ClassTemplatePartialSpecializationDecl *D) {
// We need to read the template params first because redeclarable is going to
// need them for profiling
TemplateParameterList *Params = Record.readTemplateParameterList();
D->TemplateParams = Params;
D->ArgsAsWritten = Record.readASTTemplateArgumentListInfo();

RedeclarableResult Redecl = VisitClassTemplateSpecializationDeclImpl(D);

// These are read/set from/to the first declaration.
if (ThisDeclID == Redecl.getFirstID()) {
  D->InstantiatedFromMember.setPointer(
    readDeclAs<ClassTemplatePartialSpecializationDecl>());
  D->InstantiatedFromMember.setInt(Record.readInt());
}
2260}

2262void ASTDeclReader::VisitClassScopeFunctionSpecializationDecl(
                                  ClassScopeFunctionSpecializationDecl *D) {
VisitDecl(D);
D->Specialization = readDeclAs<CXXMethodDecl>();
if (Record.readInt())
  D->TemplateArgs = Record.readASTTemplateArgumentListInfo();
2268}

2270void ASTDeclReader::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
RedeclarableResult Redecl = VisitRedeclarableTemplateDecl(D);

if (ThisDeclID == Redecl.getFirstID()) {
  // This FunctionTemplateDecl owns a CommonPtr; read it.
  SmallVector<serialization::DeclID, 32> SpecIDs;
  readDeclIDList(SpecIDs);
  ASTDeclReader::AddLazySpecializations(D, SpecIDs);
}
2279}

2281/// TODO: Unify with ClassTemplateSpecializationDecl version?
2282///       May require unifying ClassTemplate(Partial)SpecializationDecl and
2283///        VarTemplate(Partial)SpecializationDecl with a new data
2284///        structure Template(Partial)SpecializationDecl, and
2285///        using Template(Partial)SpecializationDecl as input type.
2286ASTDeclReader::RedeclarableResult
2287ASTDeclReader::VisitVarTemplateSpecializationDeclImpl(
  VarTemplateSpecializationDecl *D) {
RedeclarableResult Redecl = VisitVarDeclImpl(D);

ASTContext &C = Reader.getContext();
if (Decl *InstD = readDecl()) {
  if (auto *VTD = dyn_cast<VarTemplateDecl>(InstD)) {
    D->SpecializedTemplate = VTD;
  } else {
    SmallVector<TemplateArgument, 8> TemplArgs;
    Record.readTemplateArgumentList(TemplArgs);
    TemplateArgumentList *ArgList = TemplateArgumentList::CreateCopy(
        C, TemplArgs);
    auto *PS =
        new (C)
        VarTemplateSpecializationDecl::SpecializedPartialSpecialization();
    PS->PartialSpecialization =
        cast<VarTemplatePartialSpecializationDecl>(InstD);
    PS->TemplateArgs = ArgList;
    D->SpecializedTemplate = PS;
  }
}

// Explicit info.
if (TypeSourceInfo *TyInfo = readTypeSourceInfo()) {
  auto *ExplicitInfo =
      new (C) VarTemplateSpecializationDecl::ExplicitSpecializationInfo;
  ExplicitInfo->TypeAsWritten = TyInfo;
  ExplicitInfo->ExternLoc = readSourceLocation();
  ExplicitInfo->TemplateKeywordLoc = readSourceLocation();
  D->ExplicitInfo = ExplicitInfo;
}

SmallVector<TemplateArgument, 8> TemplArgs;
Record.readTemplateArgumentList(TemplArgs, /*Canonicalize*/ true);
D->TemplateArgs = TemplateArgumentList::CreateCopy(C, TemplArgs);
D->PointOfInstantiation = readSourceLocation();
D->SpecializationKind = (TemplateSpecializationKind)Record.readInt();
D->IsCompleteDefinition = Record.readInt();

bool writtenAsCanonicalDecl = Record.readInt();
if (writtenAsCanonicalDecl) {
  auto *CanonPattern = readDeclAs<VarTemplateDecl>();
  if (D->isCanonicalDecl()) { // It's kept in the folding set.
    // FIXME: If it's already present, merge it.
    if (auto *Partial = dyn_cast<VarTemplatePartialSpecializationDecl>(D)) {
      CanonPattern->getCommonPtr()->PartialSpecializations
          .GetOrInsertNode(Partial);
    } else {
      CanonPattern->getCommonPtr()->Specializations.GetOrInsertNode(D);
    }
  }
}

return Redecl;
2342}

2344/// TODO: Unify with ClassTemplatePartialSpecializationDecl version?
2345///       May require unifying ClassTemplate(Partial)SpecializationDecl and
2346///        VarTemplate(Partial)SpecializationDecl with a new data
2347///        structure Template(Partial)SpecializationDecl, and
2348///        using Template(Partial)SpecializationDecl as input type.
2349void ASTDeclReader::VisitVarTemplatePartialSpecializationDecl(
  VarTemplatePartialSpecializationDecl *D) {
TemplateParameterList *Params = Record.readTemplateParameterList();
D->TemplateParams = Params;
D->ArgsAsWritten = Record.readASTTemplateArgumentListInfo();

RedeclarableResult Redecl = VisitVarTemplateSpecializationDeclImpl(D);

// These are read/set from/to the first declaration.
if (ThisDeclID == Redecl.getFirstID()) {
  D->InstantiatedFromMember.setPointer(
      readDeclAs<VarTemplatePartialSpecializationDecl>());
  D->InstantiatedFromMember.setInt(Record.readInt());
}
2363}

2365void ASTDeclReader::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
VisitTypeDecl(D);

D->setDeclaredWithTypename(Record.readInt());

if (Record.readBool()) {
  NestedNameSpecifierLoc NNS = Record.readNestedNameSpecifierLoc();
  DeclarationNameInfo DN = Record.readDeclarationNameInfo();
  ConceptDecl *NamedConcept = Record.readDeclAs<ConceptDecl>();
  const ASTTemplateArgumentListInfo *ArgsAsWritten = nullptr;
  if (Record.readBool())
      ArgsAsWritten = Record.readASTTemplateArgumentListInfo();
  Expr *ImmediatelyDeclaredConstraint = Record.readExpr();
  D->setTypeConstraint(NNS, DN, /*FoundDecl=*/nullptr, NamedConcept,
                       ArgsAsWritten, ImmediatelyDeclaredConstraint);
  if ((D->ExpandedParameterPack = Record.readInt()))
    D->NumExpanded = Record.readInt();
}

if (Record.readInt())
  D->setDefaultArgument(readTypeSourceInfo());
2386}

2388void ASTDeclReader::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
VisitDeclaratorDecl(D);
// TemplateParmPosition.
D->setDepth(Record.readInt());
D->setPosition(Record.readInt());
if (D->hasPlaceholderTypeConstraint())
  D->setPlaceholderTypeConstraint(Record.readExpr());
if (D->isExpandedParameterPack()) {
  auto TypesAndInfos =
      D->getTrailingObjects<std::pair<QualType, TypeSourceInfo *>>();
  for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
    new (&TypesAndInfos[I].first) QualType(Record.readType());
    TypesAndInfos[I].second = readTypeSourceInfo();
  }
} else {
  // Rest of NonTypeTemplateParmDecl.
  D->ParameterPack = Record.readInt();
  if (Record.readInt())
    D->setDefaultArgument(Record.readExpr());
}
2408}

2410void ASTDeclReader::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
VisitTemplateDecl(D);
// TemplateParmPosition.
D->setDepth(Record.readInt());
D->setPosition(Record.readInt());
if (D->isExpandedParameterPack()) {
  auto **Data = D->getTrailingObjects<TemplateParameterList *>();
  for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
       I != N; ++I)
    Data[I] = Record.readTemplateParameterList();
} else {
  // Rest of TemplateTemplateParmDecl.
  D->ParameterPack = Record.readInt();
  if (Record.readInt())
    D->setDefaultArgument(Reader.getContext(),
                          Record.readTemplateArgumentLoc());
}
2427}

2429void ASTDeclReader::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
VisitRedeclarableTemplateDecl(D);
2431}

2433void ASTDeclReader::VisitStaticAssertDecl(StaticAssertDecl *D) {
VisitDecl(D);
D->AssertExprAndFailed.setPointer(Record.readExpr());
D->AssertExprAndFailed.setInt(Record.readInt());
D->Message = cast_or_null<StringLiteral>(Record.readExpr());
D->RParenLoc = readSourceLocation();
2439}

2441void ASTDeclReader::VisitEmptyDecl(EmptyDecl *D) {
VisitDecl(D);
2443}

2445void ASTDeclReader::VisitLifetimeExtendedTemporaryDecl(
  LifetimeExtendedTemporaryDecl *D) {
VisitDecl(D);
D->ExtendingDecl = readDeclAs<ValueDecl>();
D->ExprWithTemporary = Record.readStmt();
if (Record.readInt()) {
  D->Value = new (D->getASTContext()) APValue(Record.readAPValue());
  D->getASTContext().addDestruction(D->Value);
}
D->ManglingNumber = Record.readInt();
mergeMergeable(D);
2456}

2458std::pair<uint64_t, uint64_t>
2459ASTDeclReader::VisitDeclContext(DeclContext *DC) {
uint64_t LexicalOffset = ReadLocalOffset();
uint64_t VisibleOffset = ReadLocalOffset();
return std::make_pair(LexicalOffset, VisibleOffset);
2463}

2465template <typename T>
2466ASTDeclReader::RedeclarableResult
2467ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
DeclID FirstDeclID = readDeclID();
Decl *MergeWith = nullptr;

bool IsKeyDecl = ThisDeclID == FirstDeclID;
2
←
Assuming 'FirstDeclID' is not equal to field 'ThisDeclID'→
bool IsFirstLocalDecl = false;

uint64_t RedeclOffset = 0;

// 0 indicates that this declaration was the only declaration of its entity,
// and is used for space optimization.
if (FirstDeclID == 0) {
3
←
Assuming 'FirstDeclID' is equal to 0→
4
←
Taking true branch→
  FirstDeclID = ThisDeclID;
  IsKeyDecl = true;
  IsFirstLocalDecl = true;
} else if (unsigned N = Record.readInt()) {
  // This declaration was the first local declaration, but may have imported
  // other declarations.
  IsKeyDecl = N == 1;
  IsFirstLocalDecl = true;

  // We have some declarations that must be before us in our redeclaration
  // chain. Read them now, and remember that we ought to merge with one of
  // them.
  // FIXME: Provide a known merge target to the second and subsequent such
  // declaration.
  for (unsigned I = 0; I != N - 1; ++I)
    MergeWith = readDecl();

  RedeclOffset = ReadLocalOffset();
} else {
  // This declaration was not the first local declaration. Read the first
  // local declaration now, to trigger the import of other redeclarations.
  (void)readDecl();
}

auto *FirstDecl = cast_or_null<T>(Reader.GetDecl(FirstDeclID));
5
←
Assuming null pointer is passed into cast→
6
←
'FirstDecl' initialized to a null pointer value→
if (FirstDecl != D) {
7
←
Assuming 'FirstDecl' is not equal to 'D'→
8
←
Taking true branch→
  // We delay loading of the redeclaration chain to avoid deeply nested calls.
  // We temporarily set the first (canonical) declaration as the previous one
  // which is the one that matters and mark the real previous DeclID to be
  // loaded & attached later on.
  D->RedeclLink = Redeclarable<T>::PreviousDeclLink(FirstDecl);
  D->First = FirstDecl->getCanonicalDecl();
9
←
Called C++ object pointer is null
}

auto *DAsT = static_cast<T *>(D);

// Note that we need to load local redeclarations of this decl and build a
// decl chain for them. This must happen *after* we perform the preloading
// above; this ensures that the redeclaration chain is built in the correct
// order.
if (IsFirstLocalDecl)
  Reader.PendingDeclChains.push_back(std::make_pair(DAsT, RedeclOffset));

return RedeclarableResult(MergeWith, FirstDeclID, IsKeyDecl);
2523}

2525/// Attempts to merge the given declaration (D) with another declaration
2526/// of the same entity.
2527template<typename T>
2528void ASTDeclReader::mergeRedeclarable(Redeclarable<T> *DBase,
                                    RedeclarableResult &Redecl,
                                    DeclID TemplatePatternID) {
// If modules are not available, there is no reason to perform this merge.
if (!Reader.getContext().getLangOpts().Modules)
  return;

// If we're not the canonical declaration, we don't need to merge.
if (!DBase->isFirstDecl())
  return;

auto *D = static_cast<T *>(DBase);

if (auto *Existing = Redecl.getKnownMergeTarget())
  // We already know of an existing declaration we should merge with.
  mergeRedeclarable(D, cast<T>(Existing), Redecl, TemplatePatternID);
else if (FindExistingResult ExistingRes = findExisting(D))
  if (T *Existing = ExistingRes)
    mergeRedeclarable(D, Existing, Redecl, TemplatePatternID);
2547}

2549/// "Cast" to type T, asserting if we don't have an implicit conversion.
2550/// We use this to put code in a template that will only be valid for certain
2551/// instantiations.
2552template<typename T> static T assert_cast(T t) { return t; }
2553template<typename T> static T assert_cast(...) {
llvm_unreachable("bad assert_cast")__builtin_unreachable();
2555}

2557/// Merge together the pattern declarations from two template
2558/// declarations.
2559void ASTDeclReader::mergeTemplatePattern(RedeclarableTemplateDecl *D,
                                       RedeclarableTemplateDecl *Existing,
                                       DeclID DsID, bool IsKeyDecl) {
auto *DPattern = D->getTemplatedDecl();
auto *ExistingPattern = Existing->getTemplatedDecl();
RedeclarableResult Result(/*MergeWith*/ ExistingPattern,
                          DPattern->getCanonicalDecl()->getGlobalID(),
                          IsKeyDecl);

if (auto *DClass = dyn_cast<CXXRecordDecl>(DPattern)) {
  // Merge with any existing definition.
  // FIXME: This is duplicated in several places. Refactor.
  auto *ExistingClass =
      cast<CXXRecordDecl>(ExistingPattern)->getCanonicalDecl();
  if (auto *DDD = DClass->DefinitionData) {
    if (ExistingClass->DefinitionData) {
      MergeDefinitionData(ExistingClass, std::move(*DDD));
    } else {
      ExistingClass->DefinitionData = DClass->DefinitionData;
      // We may have skipped this before because we thought that DClass
      // was the canonical declaration.
      Reader.PendingDefinitions.insert(DClass);
    }
  }
  DClass->DefinitionData = ExistingClass->DefinitionData;

  return mergeRedeclarable(DClass, cast<TagDecl>(ExistingPattern),
                           Result);
}
if (auto *DFunction = dyn_cast<FunctionDecl>(DPattern))
  return mergeRedeclarable(DFunction, cast<FunctionDecl>(ExistingPattern),
                           Result);
if (auto *DVar = dyn_cast<VarDecl>(DPattern))
  return mergeRedeclarable(DVar, cast<VarDecl>(ExistingPattern), Result);
if (auto *DAlias = dyn_cast<TypeAliasDecl>(DPattern))
  return mergeRedeclarable(DAlias, cast<TypedefNameDecl>(ExistingPattern),
                           Result);
llvm_unreachable("merged an unknown kind of redeclarable template")__builtin_unreachable();
2597}

2599/// Attempts to merge the given declaration (D) with another declaration
2600/// of the same entity.
2601template<typename T>
2602void ASTDeclReader::mergeRedeclarable(Redeclarable<T> *DBase, T *Existing,
                                    RedeclarableResult &Redecl,
                                    DeclID TemplatePatternID) {
auto *D = static_cast<T *>(DBase);
T *ExistingCanon = Existing->getCanonicalDecl();
T *DCanon = D->getCanonicalDecl();
if (ExistingCanon != DCanon) {
  assert(DCanon->getGlobalID() == Redecl.getFirstID() &&((void)0)
         "already merged this declaration")((void)0);

  // Have our redeclaration link point back at the canonical declaration
  // of the existing declaration, so that this declaration has the
  // appropriate canonical declaration.
  D->RedeclLink = Redeclarable<T>::PreviousDeclLink(ExistingCanon);
  D->First = ExistingCanon;
  ExistingCanon->Used |= D->Used;
  D->Used = false;

  // When we merge a namespace, update its pointer to the first namespace.
  // We cannot have loaded any redeclarations of this declaration yet, so
  // there's nothing else that needs to be updated.
  if (auto *Namespace = dyn_cast<NamespaceDecl>(D))
    Namespace->AnonOrFirstNamespaceAndInline.setPointer(
        assert_cast<NamespaceDecl*>(ExistingCanon));

  // When we merge a template, merge its pattern.
  if (auto *DTemplate = dyn_cast<RedeclarableTemplateDecl>(D))
    mergeTemplatePattern(
        DTemplate, assert_cast<RedeclarableTemplateDecl*>(ExistingCanon),
        TemplatePatternID, Redecl.isKeyDecl());

  // If this declaration is a key declaration, make a note of that.
  if (Redecl.isKeyDecl())
    Reader.KeyDecls[ExistingCanon].push_back(Redecl.getFirstID());
}
2637}

2639/// ODR-like semantics for C/ObjC allow us to merge tag types and a structural
2640/// check in Sema guarantees the types can be merged (see C11 6.2.7/1 or C89
2641/// 6.1.2.6/1). Although most merging is done in Sema, we need to guarantee
2642/// that some types are mergeable during deserialization, otherwise name
2643/// lookup fails. This is the case for EnumConstantDecl.
2644static bool allowODRLikeMergeInC(NamedDecl *ND) {
if (!ND)
  return false;
// TODO: implement merge for other necessary decls.
if (isa<EnumConstantDecl>(ND))
  return true;
return false;
2651}

2653/// Attempts to merge LifetimeExtendedTemporaryDecl with
2654/// identical class definitions from two different modules.
2655void ASTDeclReader::mergeMergeable(LifetimeExtendedTemporaryDecl *D) {
// If modules are not available, there is no reason to perform this merge.
if (!Reader.getContext().getLangOpts().Modules)
  return;

LifetimeExtendedTemporaryDecl *LETDecl = D;

LifetimeExtendedTemporaryDecl *&LookupResult =
    Reader.LETemporaryForMerging[std::make_pair(
        LETDecl->getExtendingDecl(), LETDecl->getManglingNumber())];
if (LookupResult)
  Reader.getContext().setPrimaryMergedDecl(LETDecl,
                                           LookupResult->getCanonicalDecl());
else
  LookupResult = LETDecl;
2670}

2672/// Attempts to merge the given declaration (D) with another declaration
2673/// of the same entity, for the case where the entity is not actually
2674/// redeclarable. This happens, for instance, when merging the fields of
2675/// identical class definitions from two different modules.
2676template<typename T>
2677void ASTDeclReader::mergeMergeable(Mergeable<T> *D) {
// If modules are not available, there is no reason to perform this merge.
if (!Reader.getContext().getLangOpts().Modules)
  return;

// ODR-based merging is performed in C++ and in some cases (tag types) in C.
// Note that C identically-named things in different translation units are
// not redeclarations, but may still have compatible types, where ODR-like
// semantics may apply.
if (!Reader.getContext().getLangOpts().CPlusPlus &&
    !allowODRLikeMergeInC(dyn_cast<NamedDecl>(static_cast<T*>(D))))
  return;

if (FindExistingResult ExistingRes = findExisting(static_cast<T*>(D)))
  if (T *Existing = ExistingRes)
    Reader.getContext().setPrimaryMergedDecl(static_cast<T *>(D),
                                             Existing->getCanonicalDecl());
2694}

2696void ASTDeclReader::VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D) {
Record.readOMPChildren(D->Data);
VisitDecl(D);
2699}

2701void ASTDeclReader::VisitOMPAllocateDecl(OMPAllocateDecl *D) {
Record.readOMPChildren(D->Data);
VisitDecl(D);
2704}

2706void ASTDeclReader::VisitOMPRequiresDecl(OMPRequiresDecl * D) {
Record.readOMPChildren(D->Data);
VisitDecl(D);
2709}

2711void ASTDeclReader::VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D) {
VisitValueDecl(D);
D->setLocation(readSourceLocation());
Expr *In = Record.readExpr();
Expr *Out = Record.readExpr();
D->setCombinerData(In, Out);
Expr *Combiner = Record.readExpr();
D->setCombiner(Combiner);
Expr *Orig = Record.readExpr();
Expr *Priv = Record.readExpr();
D->setInitializerData(Orig, Priv);
Expr *Init = Record.readExpr();
auto IK = static_cast<OMPDeclareReductionDecl::InitKind>(Record.readInt());
D->setInitializer(Init, IK);
D->PrevDeclInScope = readDeclID();
2726}

2728void ASTDeclReader::VisitOMPDeclareMapperDecl(OMPDeclareMapperDecl *D) {
Record.readOMPChildren(D->Data);
VisitValueDecl(D);
D->VarName = Record.readDeclarationName();
D->PrevDeclInScope = readDeclID();
2733}

2735void ASTDeclReader::VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D) {
VisitVarDecl(D);
2737}

2739//===----------------------------------------------------------------------===//
2740// Attribute Reading
2741//===----------------------------------------------------------------------===//

2743namespace {
2744class AttrReader {
ASTRecordReader &Reader;

2747public:
AttrReader(ASTRecordReader &Reader) : Reader(Reader) {}

uint64_t readInt() {
  return Reader.readInt();
}

SourceRange readSourceRange() {
  return Reader.readSourceRange();
}

SourceLocation readSourceLocation() {
  return Reader.readSourceLocation();
}

Expr *readExpr() { return Reader.readExpr(); }

std::string readString() {
  return Reader.readString();
}

TypeSourceInfo *readTypeSourceInfo() {
  return Reader.readTypeSourceInfo();
}

IdentifierInfo *readIdentifier() {
  return Reader.readIdentifier();
}

VersionTuple readVersionTuple() {
  return Reader.readVersionTuple();
}

OMPTraitInfo *readOMPTraitInfo() { return Reader.readOMPTraitInfo(); }

template <typename T> T *GetLocalDeclAs(uint32_t LocalID) {
  return Reader.GetLocalDeclAs<T>(LocalID);
}
2785};
2786}

2788Attr *ASTRecordReader::readAttr() {
AttrReader Record(*this);
auto V = Record.readInt();
if (!V)
  return nullptr;

Attr *New = nullptr;
// Kind is stored as a 1-based integer because 0 is used to indicate a null
// Attr pointer.
auto Kind = static_cast<attr::Kind>(V - 1);
ASTContext &Context = getContext();

IdentifierInfo *AttrName = Record.readIdentifier();
IdentifierInfo *ScopeName = Record.readIdentifier();
SourceRange AttrRange = Record.readSourceRange();
SourceLocation ScopeLoc = Record.readSourceLocation();
unsigned ParsedKind = Record.readInt();
unsigned Syntax = Record.readInt();
unsigned SpellingIndex = Record.readInt();

AttributeCommonInfo Info(AttrName, ScopeName, AttrRange, ScopeLoc,
                         AttributeCommonInfo::Kind(ParsedKind),
                         AttributeCommonInfo::Syntax(Syntax), SpellingIndex);

2812#include "clang/Serialization/AttrPCHRead.inc"

assert(New && "Unable to decode attribute?")((void)0);
return New;
2816}

2818/// Reads attributes from the current stream position.
2819void ASTRecordReader::readAttributes(AttrVec &Attrs) {
for (unsigned I = 0, E = readInt(); I != E; ++I)
  Attrs.push_back(readAttr());
2822}

2824//===----------------------------------------------------------------------===//
2825// ASTReader Implementation
2826//===----------------------------------------------------------------------===//

2828/// Note that we have loaded the declaration with the given
2829/// Index.
2830///
2831/// This routine notes that this declaration has already been loaded,
2832/// so that future GetDecl calls will return this declaration rather
2833/// than trying to load a new declaration.
2834inline void ASTReader::LoadedDecl(unsigned Index, Decl *D) {
assert(!DeclsLoaded[Index] && "Decl loaded twice?")((void)0);
DeclsLoaded[Index] = D;
2837}

2839/// Determine whether the consumer will be interested in seeing
2840/// this declaration (via HandleTopLevelDecl).
2841///
2842/// This routine should return true for anything that might affect
2843/// code generation, e.g., inline function definitions, Objective-C
2844/// declarations with metadata, etc.
2845static bool isConsumerInterestedIn(ASTContext &Ctx, Decl *D, bool HasBody) {
// An ObjCMethodDecl is never considered as "interesting" because its
// implementation container always is.

// An ImportDecl or VarDecl imported from a module map module will get
// emitted when we import the relevant module.
if (isPartOfPerModuleInitializer(D)) {
  auto *M = D->getImportedOwningModule();
  if (M && M->Kind == Module::ModuleMapModule &&
      Ctx.DeclMustBeEmitted(D))
    return false;
}

if (isa<FileScopeAsmDecl>(D) ||
    isa<ObjCProtocolDecl>(D) ||
    isa<ObjCImplDecl>(D) ||
    isa<ImportDecl>(D) ||
    isa<PragmaCommentDecl>(D) ||
    isa<PragmaDetectMismatchDecl>(D))
  return true;
if (isa<OMPThreadPrivateDecl>(D) || isa<OMPDeclareReductionDecl>(D) ||
    isa<OMPDeclareMapperDecl>(D) || isa<OMPAllocateDecl>(D) ||
    isa<OMPRequiresDecl>(D))
  return !D->getDeclContext()->isFunctionOrMethod();
if (const auto *Var = dyn_cast<VarDecl>(D))
  return Var->isFileVarDecl() &&
         (Var->isThisDeclarationADefinition() == VarDecl::Definition ||
          OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(Var));
if (const auto *Func = dyn_cast<FunctionDecl>(D))
  return Func->doesThisDeclarationHaveABody() || HasBody;

if (auto *ES = D->getASTContext().getExternalSource())
  if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never)
    return true;

return false;
2881}

2883/// Get the correct cursor and offset for loading a declaration.
2884ASTReader::RecordLocation
2885ASTReader::DeclCursorForID(DeclID ID, SourceLocation &Loc) {
GlobalDeclMapType::iterator I = GlobalDeclMap.find(ID);
assert(I != GlobalDeclMap.end() && "Corrupted global declaration map")((void)0);
ModuleFile *M = I->second;
const DeclOffset &DOffs =
    M->DeclOffsets[ID - M->BaseDeclID - NUM_PREDEF_DECL_IDS];
Loc = TranslateSourceLocation(*M, DOffs.getLocation());
return RecordLocation(M, DOffs.getBitOffset(M->DeclsBlockStartOffset));
2893}

2895ASTReader::RecordLocation ASTReader::getLocalBitOffset(uint64_t GlobalOffset) {
auto I = GlobalBitOffsetsMap.find(GlobalOffset);

assert(I != GlobalBitOffsetsMap.end() && "Corrupted global bit offsets map")((void)0);
return RecordLocation(I->second, GlobalOffset - I->second->GlobalBitOffset);
2900}

2902uint64_t ASTReader::getGlobalBitOffset(ModuleFile &M, uint64_t LocalOffset) {
return LocalOffset + M.GlobalBitOffset;
2904}

2906static bool isSameTemplateParameterList(const ASTContext &C,
                                      const TemplateParameterList *X,
                                      const TemplateParameterList *Y);

2910/// Determine whether two template parameters are similar enough
2911/// that they may be used in declarations of the same template.
2912static bool isSameTemplateParameter(const NamedDecl *X,
                                  const NamedDecl *Y) {
if (X->getKind() != Y->getKind())
  return false;

if (const auto *TX = dyn_cast<TemplateTypeParmDecl>(X)) {
  const auto *TY = cast<TemplateTypeParmDecl>(Y);
  if (TX->isParameterPack() != TY->isParameterPack())
    return false;
  if (TX->hasTypeConstraint() != TY->hasTypeConstraint())
    return false;
  const TypeConstraint *TXTC = TX->getTypeConstraint();
  const TypeConstraint *TYTC = TY->getTypeConstraint();
  if (!TXTC != !TYTC)
    return false;
  if (TXTC && TYTC) {
    if (TXTC->getNamedConcept() != TYTC->getNamedConcept())
      return false;
    if (TXTC->hasExplicitTemplateArgs() != TYTC->hasExplicitTemplateArgs())
      return false;
    if (TXTC->hasExplicitTemplateArgs()) {
      const auto *TXTCArgs = TXTC->getTemplateArgsAsWritten();
      const auto *TYTCArgs = TYTC->getTemplateArgsAsWritten();
      if (TXTCArgs->NumTemplateArgs != TYTCArgs->NumTemplateArgs)
        return false;
      llvm::FoldingSetNodeID XID, YID;
      for (const auto &ArgLoc : TXTCArgs->arguments())
        ArgLoc.getArgument().Profile(XID, X->getASTContext());
      for (const auto &ArgLoc : TYTCArgs->arguments())
        ArgLoc.getArgument().Profile(YID, Y->getASTContext());
      if (XID != YID)
        return false;
    }
  }
  return true;
}

if (const auto *TX = dyn_cast<NonTypeTemplateParmDecl>(X)) {
  const auto *TY = cast<NonTypeTemplateParmDecl>(Y);
  return TX->isParameterPack() == TY->isParameterPack() &&
         TX->getASTContext().hasSameType(TX->getType(), TY->getType());
}

const auto *TX = cast<TemplateTemplateParmDecl>(X);
const auto *TY = cast<TemplateTemplateParmDecl>(Y);
return TX->isParameterPack() == TY->isParameterPack() &&
       isSameTemplateParameterList(TX->getASTContext(),
                                   TX->getTemplateParameters(),
                                   TY->getTemplateParameters());
2961}

2963static NamespaceDecl *getNamespace(const NestedNameSpecifier *X) {
if (auto *NS = X->getAsNamespace())
  return NS;
if (auto *NAS = X->getAsNamespaceAlias())
  return NAS->getNamespace();
return nullptr;
2969}

2971static bool isSameQualifier(const NestedNameSpecifier *X,
                          const NestedNameSpecifier *Y) {
if (auto *NSX = getNamespace(X)) {
  auto *NSY = getNamespace(Y);
  if (!NSY || NSX->getCanonicalDecl() != NSY->getCanonicalDecl())
    return false;
} else if (X->getKind() != Y->getKind())
  return false;

// FIXME: For namespaces and types, we're permitted to check that the entity
// is named via the same tokens. We should probably do so.
switch (X->getKind()) {
case NestedNameSpecifier::Identifier:
  if (X->getAsIdentifier() != Y->getAsIdentifier())
    return false;
  break;
case NestedNameSpecifier::Namespace:
case NestedNameSpecifier::NamespaceAlias:
  // We've already checked that we named the same namespace.
  break;
case NestedNameSpecifier::TypeSpec:
case NestedNameSpecifier::TypeSpecWithTemplate:
  if (X->getAsType()->getCanonicalTypeInternal() !=
      Y->getAsType()->getCanonicalTypeInternal())
    return false;
  break;
case NestedNameSpecifier::Global:
case NestedNameSpecifier::Super:
  return true;
}

// Recurse into earlier portion of NNS, if any.
auto *PX = X->getPrefix();
auto *PY = Y->getPrefix();
if (PX && PY)
  return isSameQualifier(PX, PY);
return !PX && !PY;
3008}

3010/// Determine whether two template parameter lists are similar enough
3011/// that they may be used in declarations of the same template.
3012static bool isSameTemplateParameterList(const ASTContext &C,
                                      const TemplateParameterList *X,
                                      const TemplateParameterList *Y) {
if (X->size() != Y->size())
  return false;

for (unsigned I = 0, N = X->size(); I != N; ++I)
  if (!isSameTemplateParameter(X->getParam(I), Y->getParam(I)))
    return false;

const Expr *XRC = X->getRequiresClause();
const Expr *YRC = Y->getRequiresClause();
if (!XRC != !YRC)
  return false;
if (XRC) {
  llvm::FoldingSetNodeID XRCID, YRCID;
  XRC->Profile(XRCID, C, /*Canonical=*/true);
  YRC->Profile(YRCID, C, /*Canonical=*/true);
  if (XRCID != YRCID)
    return false;
}

return true;
3035}

3037/// Determine whether the attributes we can overload on are identical for A and
3038/// B. Will ignore any overloadable attrs represented in the type of A and B.
3039static bool hasSameOverloadableAttrs(const FunctionDecl *A,
                                   const FunctionDecl *B) {
// Note that pass_object_size attributes are represented in the function's
// ExtParameterInfo, so we don't need to check them here.

llvm::FoldingSetNodeID Cand1ID, Cand2ID;
auto AEnableIfAttrs = A->specific_attrs<EnableIfAttr>();
auto BEnableIfAttrs = B->specific_attrs<EnableIfAttr>();

for (auto Pair : zip_longest(AEnableIfAttrs, BEnableIfAttrs)) {
  Optional<EnableIfAttr *> Cand1A = std::get<0>(Pair);
  Optional<EnableIfAttr *> Cand2A = std::get<1>(Pair);

  // Return false if the number of enable_if attributes is different.
  if (!Cand1A || !Cand2A)
    return false;

  Cand1ID.clear();
  Cand2ID.clear();

  (*Cand1A)->getCond()->Profile(Cand1ID, A->getASTContext(), true);
  (*Cand2A)->getCond()->Profile(Cand2ID, B->getASTContext(), true);

  // Return false if any of the enable_if expressions of A and B are
  // different.
  if (Cand1ID != Cand2ID)
    return false;
}
return true;
3068}

3070/// Determine whether the two declarations refer to the same entity.
3071static bool isSameEntity(NamedDecl *X, NamedDecl *Y) {
assert(X->getDeclName() == Y->getDeclName() && "Declaration name mismatch!")((void)0);

if (X == Y)
  return true;

// Must be in the same context.
//
// Note that we can't use DeclContext::Equals here, because the DeclContexts
// could be two different declarations of the same function. (We will fix the
// semantic DC to refer to the primary definition after merging.)
if (!declaresSameEntity(cast<Decl>(X->getDeclContext()->getRedeclContext()),
                        cast<Decl>(Y->getDeclContext()->getRedeclContext())))
  return false;

// Two typedefs refer to the same entity if they have the same underlying
// type.
if (const auto *TypedefX = dyn_cast<TypedefNameDecl>(X))
  if (const auto *TypedefY = dyn_cast<TypedefNameDecl>(Y))
    return X->getASTContext().hasSameType(TypedefX->getUnderlyingType(),
                                          TypedefY->getUnderlyingType());

// Must have the same kind.
if (X->getKind() != Y->getKind())
  return false;

// Objective-C classes and protocols with the same name always match.
if (isa<ObjCInterfaceDecl>(X) || isa<ObjCProtocolDecl>(X))
  return true;

if (isa<ClassTemplateSpecializationDecl>(X)) {
  // No need to handle these here: we merge them when adding them to the
  // template.
  return false;
}

// Compatible tags match.
if (const auto *TagX = dyn_cast<TagDecl>(X)) {
  const auto *TagY = cast<TagDecl>(Y);
  return (TagX->getTagKind() == TagY->getTagKind()) ||
    ((TagX->getTagKind() == TTK_Struct || TagX->getTagKind() == TTK_Class ||
      TagX->getTagKind() == TTK_Interface) &&
     (TagY->getTagKind() == TTK_Struct || TagY->getTagKind() == TTK_Class ||
      TagY->getTagKind() == TTK_Interface));
}

// Functions with the same type and linkage match.
// FIXME: This needs to cope with merging of prototyped/non-prototyped
// functions, etc.
if (const auto *FuncX = dyn_cast<FunctionDecl>(X)) {
  const auto *FuncY = cast<FunctionDecl>(Y);
  if (const auto *CtorX = dyn_cast<CXXConstructorDecl>(X)) {
    const auto *CtorY = cast<CXXConstructorDecl>(Y);
    if (CtorX->getInheritedConstructor() &&
        !isSameEntity(CtorX->getInheritedConstructor().getConstructor(),
                      CtorY->getInheritedConstructor().getConstructor()))
      return false;
  }

  if (FuncX->isMultiVersion() != FuncY->isMultiVersion())
    return false;

  // Multiversioned functions with different feature strings are represented
  // as separate declarations.
  if (FuncX->isMultiVersion()) {
    const auto *TAX = FuncX->getAttr<TargetAttr>();
    const auto *TAY = FuncY->getAttr<TargetAttr>();
    assert(TAX && TAY && "Multiversion Function without target attribute")((void)0);

    if (TAX->getFeaturesStr() != TAY->getFeaturesStr())
      return false;
  }

  ASTContext &C = FuncX->getASTContext();

  const Expr *XRC = FuncX->getTrailingRequiresClause();
  const Expr *YRC = FuncY->getTrailingRequiresClause();
  if (!XRC != !YRC)
    return false;
  if (XRC) {
    llvm::FoldingSetNodeID XRCID, YRCID;
    XRC->Profile(XRCID, C, /*Canonical=*/true);
    YRC->Profile(YRCID, C, /*Canonical=*/true);
    if (XRCID != YRCID)
      return false;
  }

  auto GetTypeAsWritten = [](const FunctionDecl *FD) {
    // Map to the first declaration that we've already merged into this one.
    // The TSI of redeclarations might not match (due to calling conventions
    // being inherited onto the type but not the TSI), but the TSI type of
    // the first declaration of the function should match across modules.
    FD = FD->getCanonicalDecl();
    return FD->getTypeSourceInfo() ? FD->getTypeSourceInfo()->getType()
                                   : FD->getType();
  };
  QualType XT = GetTypeAsWritten(FuncX), YT = GetTypeAsWritten(FuncY);
  if (!C.hasSameType(XT, YT)) {
    // We can get functions with different types on the redecl chain in C++17
    // if they have differing exception specifications and at least one of
    // the excpetion specs is unresolved.
    auto *XFPT = XT->getAs<FunctionProtoType>();
    auto *YFPT = YT->getAs<FunctionProtoType>();
    if (C.getLangOpts().CPlusPlus17 && XFPT && YFPT &&
        (isUnresolvedExceptionSpec(XFPT->getExceptionSpecType()) ||
         isUnresolvedExceptionSpec(YFPT->getExceptionSpecType())) &&
        C.hasSameFunctionTypeIgnoringExceptionSpec(XT, YT))
      return true;
    return false;
  }

  return FuncX->getLinkageInternal() == FuncY->getLinkageInternal() &&
         hasSameOverloadableAttrs(FuncX, FuncY);
}

// Variables with the same type and linkage match.
if (const auto *VarX = dyn_cast<VarDecl>(X)) {
  const auto *VarY = cast<VarDecl>(Y);
  if (VarX->getLinkageInternal() == VarY->getLinkageInternal()) {
    ASTContext &C = VarX->getASTContext();
    if (C.hasSameType(VarX->getType(), VarY->getType()))
      return true;

    // We can get decls with different types on the redecl chain. Eg.
    // template <typename T> struct S { static T Var[]; }; // #1
    // template <typename T> T S<T>::Var[sizeof(T)]; // #2
    // Only? happens when completing an incomplete array type. In this case
    // when comparing #1 and #2 we should go through their element type.
    const ArrayType *VarXTy = C.getAsArrayType(VarX->getType());
    const ArrayType *VarYTy = C.getAsArrayType(VarY->getType());
    if (!VarXTy || !VarYTy)
      return false;
    if (VarXTy->isIncompleteArrayType() || VarYTy->isIncompleteArrayType())
      return C.hasSameType(VarXTy->getElementType(), VarYTy->getElementType());
  }
  return false;
}

// Namespaces with the same name and inlinedness match.
if (const auto *NamespaceX = dyn_cast<NamespaceDecl>(X)) {
  const auto *NamespaceY = cast<NamespaceDecl>(Y);
  return NamespaceX->isInline() == NamespaceY->isInline();
}

// Identical template names and kinds match if their template parameter lists
// and patterns match.
if (const auto *TemplateX = dyn_cast<TemplateDecl>(X)) {
  const auto *TemplateY = cast<TemplateDecl>(Y);
  return isSameEntity(TemplateX->getTemplatedDecl(),
                      TemplateY->getTemplatedDecl()) &&
         isSameTemplateParameterList(TemplateX->getASTContext(),
                                     TemplateX->getTemplateParameters(),
                                     TemplateY->getTemplateParameters());
}

// Fields with the same name and the same type match.
if (const auto *FDX = dyn_cast<FieldDecl>(X)) {
  const auto *FDY = cast<FieldDecl>(Y);
  // FIXME: Also check the bitwidth is odr-equivalent, if any.
  return X->getASTContext().hasSameType(FDX->getType(), FDY->getType());
}

// Indirect fields with the same target field match.
if (const auto *IFDX = dyn_cast<IndirectFieldDecl>(X)) {
  const auto *IFDY = cast<IndirectFieldDecl>(Y);
  return IFDX->getAnonField()->getCanonicalDecl() ==
         IFDY->getAnonField()->getCanonicalDecl();
}

// Enumerators with the same name match.
if (isa<EnumConstantDecl>(X))
  // FIXME: Also check the value is odr-equivalent.
  return true;

// Using shadow declarations with the same target match.
if (const auto *USX = dyn_cast<UsingShadowDecl>(X)) {
  const auto *USY = cast<UsingShadowDecl>(Y);
  return USX->getTargetDecl() == USY->getTargetDecl();
}

// Using declarations with the same qualifier match. (We already know that
// the name matches.)
if (const auto *UX = dyn_cast<UsingDecl>(X)) {
  const auto *UY = cast<UsingDecl>(Y);
  return isSameQualifier(UX->getQualifier(), UY->getQualifier()) &&
         UX->hasTypename() == UY->hasTypename() &&
         UX->isAccessDeclaration() == UY->isAccessDeclaration();
}
if (const auto *UX = dyn_cast<UnresolvedUsingValueDecl>(X)) {
  const auto *UY = cast<UnresolvedUsingValueDecl>(Y);
  return isSameQualifier(UX->getQualifier(), UY->getQualifier()) &&
         UX->isAccessDeclaration() == UY->isAccessDeclaration();
}
if (const auto *UX = dyn_cast<UnresolvedUsingTypenameDecl>(X)) {
  return isSameQualifier(
      UX->getQualifier(),
      cast<UnresolvedUsingTypenameDecl>(Y)->getQualifier());
}

// Using-pack declarations are only created by instantiation, and match if
// they're instantiated from matching UnresolvedUsing...Decls.
if (const auto *UX = dyn_cast<UsingPackDecl>(X)) {
  return declaresSameEntity(
      UX->getInstantiatedFromUsingDecl(),
      cast<UsingPackDecl>(Y)->getInstantiatedFromUsingDecl());
}

// Namespace alias definitions with the same target match.
if (const auto *NAX = dyn_cast<NamespaceAliasDecl>(X)) {
  const auto *NAY = cast<NamespaceAliasDecl>(Y);
  return NAX->getNamespace()->Equals(NAY->getNamespace());
}

return false;
3285}

3287/// Find the context in which we should search for previous declarations when
3288/// looking for declarations to merge.
3289DeclContext *ASTDeclReader::getPrimaryContextForMerging(ASTReader &Reader,
                                                      DeclContext *DC) {
if (auto *ND = dyn_cast<NamespaceDecl>(DC))
  return ND->getOriginalNamespace();

if (auto *RD = dyn_cast<CXXRecordDecl>(DC)) {
  // Try to dig out the definition.
  auto *DD = RD->DefinitionData;
  if (!DD)
    DD = RD->getCanonicalDecl()->DefinitionData;

  // If there's no definition yet, then DC's definition is added by an update
  // record, but we've not yet loaded that update record. In this case, we
  // commit to DC being the canonical definition now, and will fix this when
  // we load the update record.
  if (!DD) {
    DD = new (Reader.getContext()) struct CXXRecordDecl::DefinitionData(RD);
    RD->setCompleteDefinition(true);
    RD->DefinitionData = DD;
    RD->getCanonicalDecl()->DefinitionData = DD;

    // Track that we did this horrible thing so that we can fix it later.
    Reader.PendingFakeDefinitionData.insert(
        std::make_pair(DD, ASTReader::PendingFakeDefinitionKind::Fake));
  }

  return DD->Definition;
}

if (auto *ED = dyn_cast<EnumDecl>(DC))
  return ED->getASTContext().getLangOpts().CPlusPlus? ED->getDefinition()
                                                    : nullptr;

// We can see the TU here only if we have no Sema object. In that case,
// there's no TU scope to look in, so using the DC alone is sufficient.
if (auto *TU = dyn_cast<TranslationUnitDecl>(DC))
  return TU;

return nullptr;
3328}

3330ASTDeclReader::FindExistingResult::~FindExistingResult() {
// Record that we had a typedef name for linkage whether or not we merge
// with that declaration.
if (TypedefNameForLinkage) {
  DeclContext *DC = New->getDeclContext()->getRedeclContext();
  Reader.ImportedTypedefNamesForLinkage.insert(
      std::make_pair(std::make_pair(DC, TypedefNameForLinkage), New));
  return;
}

if (!AddResult || Existing)
  return;

DeclarationName Name = New->getDeclName();
DeclContext *DC = New->getDeclContext()->getRedeclContext();
if (needsAnonymousDeclarationNumber(New)) {
  setAnonymousDeclForMerging(Reader, New->getLexicalDeclContext(),
                             AnonymousDeclNumber, New);
} else if (DC->isTranslationUnit() &&
           !Reader.getContext().getLangOpts().CPlusPlus) {
  if (Reader.getIdResolver().tryAddTopLevelDecl(New, Name))
    Reader.PendingFakeLookupResults[Name.getAsIdentifierInfo()]
          .push_back(New);
} else if (DeclContext *MergeDC = getPrimaryContextForMerging(Reader, DC)) {
  // Add the declaration to its redeclaration context so later merging
  // lookups will find it.
  MergeDC->makeDeclVisibleInContextImpl(New, /*Internal*/true);
}
3358}

3360/// Find the declaration that should be merged into, given the declaration found
3361/// by name lookup. If we're merging an anonymous declaration within a typedef,
3362/// we need a matching typedef, and we merge with the type inside it.
3363static NamedDecl *getDeclForMerging(NamedDecl *Found,
                                  bool IsTypedefNameForLinkage) {
if (!IsTypedefNameForLinkage)
  return Found;

// If we found a typedef declaration that gives a name to some other
// declaration, then we want that inner declaration. Declarations from
// AST files are handled via ImportedTypedefNamesForLinkage.
if (Found->isFromASTFile())
  return nullptr;

if (auto *TND = dyn_cast<TypedefNameDecl>(Found))
  return TND->getAnonDeclWithTypedefName(/*AnyRedecl*/true);

return nullptr;
3378}

3380/// Find the declaration to use to populate the anonymous declaration table
3381/// for the given lexical DeclContext. We only care about finding local
3382/// definitions of the context; we'll merge imported ones as we go.
3383DeclContext *
3384ASTDeclReader::getPrimaryDCForAnonymousDecl(DeclContext *LexicalDC) {
// For classes, we track the definition as we merge.
if (auto *RD = dyn_cast<CXXRecordDecl>(LexicalDC)) {
  auto *DD = RD->getCanonicalDecl()->DefinitionData;
  return DD ? DD->Definition : nullptr;
}

// For anything else, walk its merged redeclarations looking for a definition.
// Note that we can't just call getDefinition here because the redeclaration
// chain isn't wired up.
for (auto *D : merged_redecls(cast<Decl>(LexicalDC))) {
  if (auto *FD = dyn_cast<FunctionDecl>(D))
    if (FD->isThisDeclarationADefinition())
      return FD;
  if (auto *MD = dyn_cast<ObjCMethodDecl>(D))
    if (MD->isThisDeclarationADefinition())
      return MD;
}

// No merged definition yet.
return nullptr;
3405}

3407NamedDecl *ASTDeclReader::getAnonymousDeclForMerging(ASTReader &Reader,
                                                   DeclContext *DC,
                                                   unsigned Index) {
// If the lexical context has been merged, look into the now-canonical
// definition.
auto *CanonDC = cast<Decl>(DC)->getCanonicalDecl();

// If we've seen this before, return the canonical declaration.
auto &Previous = Reader.AnonymousDeclarationsForMerging[CanonDC];
if (Index < Previous.size() && Previous[Index])
  return Previous[Index];

// If this is the first time, but we have parsed a declaration of the context,
// build the anonymous declaration list from the parsed declaration.
auto *PrimaryDC = getPrimaryDCForAnonymousDecl(DC);
if (PrimaryDC && !cast<Decl>(PrimaryDC)->isFromASTFile()) {
  numberAnonymousDeclsWithin(PrimaryDC, [&](NamedDecl *ND, unsigned Number) {
    if (Previous.size() == Number)
      Previous.push_back(cast<NamedDecl>(ND->getCanonicalDecl()));
    else
      Previous[Number] = cast<NamedDecl>(ND->getCanonicalDecl());
  });
}

return Index < Previous.size() ? Previous[Index] : nullptr;
3432}

3434void ASTDeclReader::setAnonymousDeclForMerging(ASTReader &Reader,
                                             DeclContext *DC, unsigned Index,
                                             NamedDecl *D) {
auto *CanonDC = cast<Decl>(DC)->getCanonicalDecl();

auto &Previous = Reader.AnonymousDeclarationsForMerging[CanonDC];
if (Index >= Previous.size())
  Previous.resize(Index + 1);
if (!Previous[Index])
  Previous[Index] = D;
3444}

3446ASTDeclReader::FindExistingResult ASTDeclReader::findExisting(NamedDecl *D) {
DeclarationName Name = TypedefNameForLinkage ? TypedefNameForLinkage
                                             : D->getDeclName();

if (!Name && !needsAnonymousDeclarationNumber(D)) {
  // Don't bother trying to find unnamed declarations that are in
  // unmergeable contexts.
  FindExistingResult Result(Reader, D, /*Existing=*/nullptr,
                            AnonymousDeclNumber, TypedefNameForLinkage);
  Result.suppress();
  return Result;
}

DeclContext *DC = D->getDeclContext()->getRedeclContext();
if (TypedefNameForLinkage) {
  auto It = Reader.ImportedTypedefNamesForLinkage.find(
      std::make_pair(DC, TypedefNameForLinkage));
  if (It != Reader.ImportedTypedefNamesForLinkage.end())
    if (isSameEntity(It->second, D))
      return FindExistingResult(Reader, D, It->second, AnonymousDeclNumber,
                                TypedefNameForLinkage);
  // Go on to check in other places in case an existing typedef name
  // was not imported.
}

if (needsAnonymousDeclarationNumber(D)) {
  // This is an anonymous declaration that we may need to merge. Look it up
  // in its context by number.
  if (auto *Existing = getAnonymousDeclForMerging(
          Reader, D->getLexicalDeclContext(), AnonymousDeclNumber))
    if (isSameEntity(Existing, D))
      return FindExistingResult(Reader, D, Existing, AnonymousDeclNumber,
                                TypedefNameForLinkage);
} else if (DC->isTranslationUnit() &&
           !Reader.getContext().getLangOpts().CPlusPlus) {
  IdentifierResolver &IdResolver = Reader.getIdResolver();

  // Temporarily consider the identifier to be up-to-date. We don't want to
  // cause additional lookups here.
  class UpToDateIdentifierRAII {
    IdentifierInfo *II;
    bool WasOutToDate = false;

  public:
    explicit UpToDateIdentifierRAII(IdentifierInfo *II) : II(II) {
      if (II) {
        WasOutToDate = II->isOutOfDate();
        if (WasOutToDate)
          II->setOutOfDate(false);
      }
    }

    ~UpToDateIdentifierRAII() {
      if (WasOutToDate)
        II->setOutOfDate(true);
    }
  } UpToDate(Name.getAsIdentifierInfo());

  for (IdentifierResolver::iterator I = IdResolver.begin(Name),
                                 IEnd = IdResolver.end();
       I != IEnd; ++I) {
    if (NamedDecl *Existing = getDeclForMerging(*I, TypedefNameForLinkage))
      if (isSameEntity(Existing, D))
        return FindExistingResult(Reader, D, Existing, AnonymousDeclNumber,
                                  TypedefNameForLinkage);
  }
} else if (DeclContext *MergeDC = getPrimaryContextForMerging(Reader, DC)) {
  DeclContext::lookup_result R = MergeDC->noload_lookup(Name);
  for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E; ++I) {
    if (NamedDecl *Existing = getDeclForMerging(*I, TypedefNameForLinkage))
      if (isSameEntity(Existing, D))
        return FindExistingResult(Reader, D, Existing, AnonymousDeclNumber,
                                  TypedefNameForLinkage);
  }
} else {
  // Not in a mergeable context.
  return FindExistingResult(Reader);
}

// If this declaration is from a merged context, make a note that we need to
// check that the canonical definition of that context contains the decl.
//
// FIXME: We should do something similar if we merge two definitions of the
// same template specialization into the same CXXRecordDecl.
auto MergedDCIt = Reader.MergedDeclContexts.find(D->getLexicalDeclContext());
if (MergedDCIt != Reader.MergedDeclContexts.end() &&
    MergedDCIt->second == D->getDeclContext())
  Reader.PendingOdrMergeChecks.push_back(D);

return FindExistingResult(Reader, D, /*Existing=*/nullptr,
                          AnonymousDeclNumber, TypedefNameForLinkage);
3537}

3539template<typename DeclT>
3540Decl *ASTDeclReader::getMostRecentDeclImpl(Redeclarable<DeclT> *D) {
return D->RedeclLink.getLatestNotUpdated();
3542}

3544Decl *ASTDeclReader::getMostRecentDeclImpl(...) {
llvm_unreachable("getMostRecentDecl on non-redeclarable declaration")__builtin_unreachable();
3546}

3548Decl *ASTDeclReader::getMostRecentDecl(Decl *D) {
assert(D)((void)0);

switch (D->getKind()) {
3552#define ABSTRACT_DECL(TYPE)
3553#define DECL(TYPE, BASE)                               \
case Decl::TYPE:                                     \
  return getMostRecentDeclImpl(cast<TYPE##Decl>(D));
3556#include "clang/AST/DeclNodes.inc"
}
llvm_unreachable("unknown decl kind")__builtin_unreachable();
3559}

3561Decl *ASTReader::getMostRecentExistingDecl(Decl *D) {
return ASTDeclReader::getMostRecentDecl(D->getCanonicalDecl());
3563}

3565void ASTDeclReader::mergeInheritableAttributes(ASTReader &Reader, Decl *D,
                                             Decl *Previous) {
InheritableAttr *NewAttr = nullptr;
ASTContext &Context = Reader.getContext();
const auto *IA = Previous->getAttr<MSInheritanceAttr>();

if (IA && !D->hasAttr<MSInheritanceAttr>()) {
  NewAttr = cast<InheritableAttr>(IA->clone(Context));
  NewAttr->setInherited(true);
  D->addAttr(NewAttr);
}
3576}

3578template<typename DeclT>
3579void ASTDeclReader::attachPreviousDeclImpl(ASTReader &Reader,
                                         Redeclarable<DeclT> *D,
                                         Decl *Previous, Decl *Canon) {
D->RedeclLink.setPrevious(cast<DeclT>(Previous));
D->First = cast<DeclT>(Previous)->First;
3584}

3586namespace clang {

3588template<>
3589void ASTDeclReader::attachPreviousDeclImpl(ASTReader &Reader,
                                         Redeclarable<VarDecl> *D,
                                         Decl *Previous, Decl *Canon) {
auto *VD = static_cast<VarDecl *>(D);
auto *PrevVD = cast<VarDecl>(Previous);
D->RedeclLink.setPrevious(PrevVD);
D->First = PrevVD->First;

// We should keep at most one definition on the chain.
// FIXME: Cache the definition once we've found it. Building a chain with
// N definitions currently takes O(N^2) time here.
if (VD->isThisDeclarationADefinition() == VarDecl::Definition) {
  for (VarDecl *CurD = PrevVD; CurD; CurD = CurD->getPreviousDecl()) {
    if (CurD->isThisDeclarationADefinition() == VarDecl::Definition) {
      Reader.mergeDefinitionVisibility(CurD, VD);
      VD->demoteThisDefinitionToDeclaration();
      break;
    }
  }
}
3609}

3611static bool isUndeducedReturnType(QualType T) {
auto *DT = T->getContainedDeducedType();
return DT && !DT->isDeduced();
3614}

3616template<>
3617void ASTDeclReader::attachPreviousDeclImpl(ASTReader &Reader,
                                         Redeclarable<FunctionDecl> *D,
                                         Decl *Previous, Decl *Canon) {
auto *FD = static_cast<FunctionDecl *>(D);
auto *PrevFD = cast<FunctionDecl>(Previous);

FD->RedeclLink.setPrevious(PrevFD);
FD->First = PrevFD->First;

// If the previous declaration is an inline function declaration, then this
// declaration is too.
if (PrevFD->isInlined() != FD->isInlined()) {
  // FIXME: [dcl.fct.spec]p4:
  //   If a function with external linkage is declared inline in one
  //   translation unit, it shall be declared inline in all translation
  //   units in which it appears.
  //
  // Be careful of this case:
  //
  // module A:
  //   template<typename T> struct X { void f(); };
  //   template<typename T> inline void X<T>::f() {}
  //
  // module B instantiates the declaration of X<int>::f
  // module C instantiates the definition of X<int>::f
  //
  // If module B and C are merged, we do not have a violation of this rule.
  FD->setImplicitlyInline(true);
}

auto *FPT = FD->getType()->getAs<FunctionProtoType>();
auto *PrevFPT = PrevFD->getType()->getAs<FunctionProtoType>();
if (FPT && PrevFPT) {
  // If we need to propagate an exception specification along the redecl
  // chain, make a note of that so that we can do so later.
  bool IsUnresolved = isUnresolvedExceptionSpec(FPT->getExceptionSpecType());
  bool WasUnresolved =
      isUnresolvedExceptionSpec(PrevFPT->getExceptionSpecType());
  if (IsUnresolved != WasUnresolved)
    Reader.PendingExceptionSpecUpdates.insert(
        {Canon, IsUnresolved ? PrevFD : FD});

  // If we need to propagate a deduced return type along the redecl chain,
  // make a note of that so that we can do it later.
  bool IsUndeduced = isUndeducedReturnType(FPT->getReturnType());
  bool WasUndeduced = isUndeducedReturnType(PrevFPT->getReturnType());
  if (IsUndeduced != WasUndeduced)
    Reader.PendingDeducedTypeUpdates.insert(
        {cast<FunctionDecl>(Canon),
         (IsUndeduced ? PrevFPT : FPT)->getReturnType()});
}
3668}

3670} // namespace clang

3672void ASTDeclReader::attachPreviousDeclImpl(ASTReader &Reader, ...) {
llvm_unreachable("attachPreviousDecl on non-redeclarable declaration")__builtin_unreachable();
3674}

3676/// Inherit the default template argument from \p From to \p To. Returns
3677/// \c false if there is no default template for \p From.
3678template <typename ParmDecl>
3679static bool inheritDefaultTemplateArgument(ASTContext &Context, ParmDecl *From,
                                         Decl *ToD) {
auto *To = cast<ParmDecl>(ToD);
if (!From->hasDefaultArgument())
  return false;
To->setInheritedDefaultArgument(Context, From);
return true;
3686}

3688static void inheritDefaultTemplateArguments(ASTContext &Context,
                                          TemplateDecl *From,
                                          TemplateDecl *To) {
auto *FromTP = From->getTemplateParameters();
auto *ToTP = To->getTemplateParameters();
assert(FromTP->size() == ToTP->size() && "merged mismatched templates?")((void)0);

for (unsigned I = 0, N = FromTP->size(); I != N; ++I) {
  NamedDecl *FromParam = FromTP->getParam(I);
  NamedDecl *ToParam = ToTP->getParam(I);

  if (auto *FTTP = dyn_cast<TemplateTypeParmDecl>(FromParam))
    inheritDefaultTemplateArgument(Context, FTTP, ToParam);
  else if (auto *FNTTP = dyn_cast<NonTypeTemplateParmDecl>(FromParam))
    inheritDefaultTemplateArgument(Context, FNTTP, ToParam);
  else
    inheritDefaultTemplateArgument(
            Context, cast<TemplateTemplateParmDecl>(FromParam), ToParam);
}
3707}

3709void ASTDeclReader::attachPreviousDecl(ASTReader &Reader, Decl *D,
                                     Decl *Previous, Decl *Canon) {
assert(D && Previous)((void)0);

switch (D->getKind()) {
3714#define ABSTRACT_DECL(TYPE)
3715#define DECL(TYPE, BASE)                                                  \
case Decl::TYPE:                                                        \
  attachPreviousDeclImpl(Reader, cast<TYPE##Decl>(D), Previous, Canon); \
  break;
3719#include "clang/AST/DeclNodes.inc"
}

// If the declaration was visible in one module, a redeclaration of it in
// another module remains visible even if it wouldn't be visible by itself.
//
// FIXME: In this case, the declaration should only be visible if a module
//        that makes it visible has been imported.
D->IdentifierNamespace |=
    Previous->IdentifierNamespace &
    (Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Type);

// If the declaration declares a template, it may inherit default arguments
// from the previous declaration.
if (auto *TD = dyn_cast<TemplateDecl>(D))
  inheritDefaultTemplateArguments(Reader.getContext(),
                                  cast<TemplateDecl>(Previous), TD);

// If any of the declaration in the chain contains an Inheritable attribute,
// it needs to be added to all the declarations in the redeclarable chain.
// FIXME: Only the logic of merging MSInheritableAttr is present, it should
// be extended for all inheritable attributes.
mergeInheritableAttributes(Reader, D, Previous);
3742}

3744template<typename DeclT>
3745void ASTDeclReader::attachLatestDeclImpl(Redeclarable<DeclT> *D, Decl *Latest) {
D->RedeclLink.setLatest(cast<DeclT>(Latest));
3747}

3749void ASTDeclReader::attachLatestDeclImpl(...) {
llvm_unreachable("attachLatestDecl on non-redeclarable declaration")__builtin_unreachable();
3751}

3753void ASTDeclReader::attachLatestDecl(Decl *D, Decl *Latest) {
assert(D && Latest)((void)0);

switch (D->getKind()) {
3757#define ABSTRACT_DECL(TYPE)
3758#define DECL(TYPE, BASE)                                  \
case Decl::TYPE:                                        \
  attachLatestDeclImpl(cast<TYPE##Decl>(D), Latest); \
  break;
3762#include "clang/AST/DeclNodes.inc"
}
3764}

3766template<typename DeclT>
3767void ASTDeclReader::markIncompleteDeclChainImpl(Redeclarable<DeclT> *D) {
D->RedeclLink.markIncomplete();
3769}

3771void ASTDeclReader::markIncompleteDeclChainImpl(...) {
llvm_unreachable("markIncompleteDeclChain on non-redeclarable declaration")__builtin_unreachable();
3773}

3775void ASTReader::markIncompleteDeclChain(Decl *D) {
switch (D->getKind()) {
3777#define ABSTRACT_DECL(TYPE)
3778#define DECL(TYPE, BASE)                                             \
case Decl::TYPE:                                                   \
  ASTDeclReader::markIncompleteDeclChainImpl(cast<TYPE##Decl>(D)); \
  break;
3782#include "clang/AST/DeclNodes.inc"
}
3784}

3786/// Read the declaration at the given offset from the AST file.
3787Decl *ASTReader::ReadDeclRecord(DeclID ID) {
unsigned Index = ID - NUM_PREDEF_DECL_IDS;
SourceLocation DeclLoc;
RecordLocation Loc = DeclCursorForID(ID, DeclLoc);
llvm::BitstreamCursor &DeclsCursor = Loc.F->DeclsCursor;
// Keep track of where we are in the stream, then jump back there
// after reading this declaration.
SavedStreamPosition SavedPosition(DeclsCursor);

ReadingKindTracker ReadingKind(Read_Decl, *this);

// Note that we are loading a declaration record.
Deserializing ADecl(this);

auto Fail = [](const char *what, llvm::Error &&Err) {
  llvm::report_fatal_error(Twine("ASTReader::readDeclRecord failed ") + what +
                           ": " + toString(std::move(Err)));
};

if (llvm::Error JumpFailed = DeclsCursor.JumpToBit(Loc.Offset))
  Fail("jumping", std::move(JumpFailed));
ASTRecordReader Record(*this, *Loc.F);
ASTDeclReader Reader(*this, Record, Loc, ID, DeclLoc);
Expected<unsigned> MaybeCode = DeclsCursor.ReadCode();
if (!MaybeCode)
  Fail("reading code", MaybeCode.takeError());
unsigned Code = MaybeCode.get();

ASTContext &Context = getContext();
Decl *D = nullptr;
Expected<unsigned> MaybeDeclCode = Record.readRecord(DeclsCursor, Code);
if (!MaybeDeclCode)
  llvm::report_fatal_error(
      "ASTReader::readDeclRecord failed reading decl code: " +
      toString(MaybeDeclCode.takeError()));
switch ((DeclCode)MaybeDeclCode.get()) {
case DECL_CONTEXT_LEXICAL:
case DECL_CONTEXT_VISIBLE:
  llvm_unreachable("Record cannot be de-serialized with readDeclRecord")__builtin_unreachable();
case DECL_TYPEDEF:
  D = TypedefDecl::CreateDeserialized(Context, ID);
  break;
case DECL_TYPEALIAS:
  D = TypeAliasDecl::CreateDeserialized(Context, ID);
  break;
case DECL_ENUM:
  D = EnumDecl::CreateDeserialized(Context, ID);
  break;
case DECL_RECORD:
  D = RecordDecl::CreateDeserialized(Context, ID);
  break;
case DECL_ENUM_CONSTANT:
  D = EnumConstantDecl::CreateDeserialized(Context, ID);
  break;
case DECL_FUNCTION:
  D = FunctionDecl::CreateDeserialized(Context, ID);
  break;
case DECL_LINKAGE_SPEC:
  D = LinkageSpecDecl::CreateDeserialized(Context, ID);
  break;
case DECL_EXPORT:
  D = ExportDecl::CreateDeserialized(Context, ID);
  break;
case DECL_LABEL:
  D = LabelDecl::CreateDeserialized(Context, ID);
  break;
case DECL_NAMESPACE:
  D = NamespaceDecl::CreateDeserialized(Context, ID);
  break;
case DECL_NAMESPACE_ALIAS:
  D = NamespaceAliasDecl::CreateDeserialized(Context, ID);
  break;
case DECL_USING:
  D = UsingDecl::CreateDeserialized(Context, ID);
  break;
case DECL_USING_PACK:
  D = UsingPackDecl::CreateDeserialized(Context, ID, Record.readInt());
  break;
case DECL_USING_SHADOW:
  D = UsingShadowDecl::CreateDeserialized(Context, ID);
  break;
case DECL_USING_ENUM:
  D = UsingEnumDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CONSTRUCTOR_USING_SHADOW:
  D = ConstructorUsingShadowDecl::CreateDeserialized(Context, ID);
  break;
case DECL_USING_DIRECTIVE:
  D = UsingDirectiveDecl::CreateDeserialized(Context, ID);
  break;
case DECL_UNRESOLVED_USING_VALUE:
  D = UnresolvedUsingValueDecl::CreateDeserialized(Context, ID);
  break;
case DECL_UNRESOLVED_USING_TYPENAME:
  D = UnresolvedUsingTypenameDecl::CreateDeserialized(Context, ID);
  break;
case DECL_UNRESOLVED_USING_IF_EXISTS:
  D = UnresolvedUsingIfExistsDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CXX_RECORD:
  D = CXXRecordDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CXX_DEDUCTION_GUIDE:
  D = CXXDeductionGuideDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CXX_METHOD:
  D = CXXMethodDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CXX_CONSTRUCTOR:
  D = CXXConstructorDecl::CreateDeserialized(Context, ID, Record.readInt());
  break;
case DECL_CXX_DESTRUCTOR:
  D = CXXDestructorDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CXX_CONVERSION:
  D = CXXConversionDecl::CreateDeserialized(Context, ID);
  break;
case DECL_ACCESS_SPEC:
  D = AccessSpecDecl::CreateDeserialized(Context, ID);
  break;
case DECL_FRIEND:
  D = FriendDecl::CreateDeserialized(Context, ID, Record.readInt());
  break;
case DECL_FRIEND_TEMPLATE:
  D = FriendTemplateDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CLASS_TEMPLATE:
  D = ClassTemplateDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CLASS_TEMPLATE_SPECIALIZATION:
  D = ClassTemplateSpecializationDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION:
  D = ClassTemplatePartialSpecializationDecl::CreateDeserialized(Context, ID);
  break;
case DECL_VAR_TEMPLATE:
  D = VarTemplateDecl::CreateDeserialized(Context, ID);
  break;
case DECL_VAR_TEMPLATE_SPECIALIZATION:
  D = VarTemplateSpecializationDecl::CreateDeserialized(Context, ID);
  break;
case DECL_VAR_TEMPLATE_PARTIAL_SPECIALIZATION:
  D = VarTemplatePartialSpecializationDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION:
  D = ClassScopeFunctionSpecializationDecl::CreateDeserialized(Context, ID);
  break;
case DECL_FUNCTION_TEMPLATE:
  D = FunctionTemplateDecl::CreateDeserialized(Context, ID);
  break;
case DECL_TEMPLATE_TYPE_PARM: {
  bool HasTypeConstraint = Record.readInt();
  D = TemplateTypeParmDecl::CreateDeserialized(Context, ID,
                                               HasTypeConstraint);
  break;
}
case DECL_NON_TYPE_TEMPLATE_PARM: {
  bool HasTypeConstraint = Record.readInt();
  D = NonTypeTemplateParmDecl::CreateDeserialized(Context, ID,
                                                  HasTypeConstraint);
  break;
}
case DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK: {
  bool HasTypeConstraint = Record.readInt();
  D = NonTypeTemplateParmDecl::CreateDeserialized(Context, ID,
                                                  Record.readInt(),
                                                  HasTypeConstraint);
  break;
}
case DECL_TEMPLATE_TEMPLATE_PARM:
  D = TemplateTemplateParmDecl::CreateDeserialized(Context, ID);
  break;
case DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK:
  D = TemplateTemplateParmDecl::CreateDeserialized(Context, ID,
                                                   Record.readInt());
  break;
case DECL_TYPE_ALIAS_TEMPLATE:
  D = TypeAliasTemplateDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CONCEPT:
  D = ConceptDecl::CreateDeserialized(Context, ID);
  break;
case DECL_REQUIRES_EXPR_BODY:
  D = RequiresExprBodyDecl::CreateDeserialized(Context, ID);
  break;
case DECL_STATIC_ASSERT:
  D = StaticAssertDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_METHOD:
  D = ObjCMethodDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_INTERFACE:
  D = ObjCInterfaceDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_IVAR:
  D = ObjCIvarDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_PROTOCOL:
  D = ObjCProtocolDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_AT_DEFS_FIELD:
  D = ObjCAtDefsFieldDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_CATEGORY:
  D = ObjCCategoryDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_CATEGORY_IMPL:
  D = ObjCCategoryImplDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_IMPLEMENTATION:
  D = ObjCImplementationDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_COMPATIBLE_ALIAS:
  D = ObjCCompatibleAliasDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_PROPERTY:
  D = ObjCPropertyDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_PROPERTY_IMPL:
  D = ObjCPropertyImplDecl::CreateDeserialized(Context, ID);
  break;
case DECL_FIELD:
  D = FieldDecl::CreateDeserialized(Context, ID);
  break;
case DECL_INDIRECTFIELD:
  D = IndirectFieldDecl::CreateDeserialized(Context, ID);
  break;
case DECL_VAR:
  D = VarDecl::CreateDeserialized(Context, ID);
  break;
case DECL_IMPLICIT_PARAM:
  D = ImplicitParamDecl::CreateDeserialized(Context, ID);
  break;
case DECL_PARM_VAR:
  D = ParmVarDecl::CreateDeserialized(Context, ID);
  break;
case DECL_DECOMPOSITION:
  D = DecompositionDecl::CreateDeserialized(Context, ID, Record.readInt());
  break;
case DECL_BINDING:
  D = BindingDecl::CreateDeserialized(Context, ID);
  break;
case DECL_FILE_SCOPE_ASM:
  D = FileScopeAsmDecl::CreateDeserialized(Context, ID);
  break;
case DECL_BLOCK:
  D = BlockDecl::CreateDeserialized(Context, ID);
  break;
case DECL_MS_PROPERTY:
  D = MSPropertyDecl::CreateDeserialized(Context, ID);
  break;
case DECL_MS_GUID:
  D = MSGuidDecl::CreateDeserialized(Context, ID);
  break;
case DECL_TEMPLATE_PARAM_OBJECT:
  D = TemplateParamObjectDecl::CreateDeserialized(Context, ID);
  break;
case DECL_CAPTURED:
  D = CapturedDecl::CreateDeserialized(Context, ID, Record.readInt());
  break;
case DECL_CXX_BASE_SPECIFIERS:
  Error("attempt to read a C++ base-specifier record as a declaration");
  return nullptr;
case DECL_CXX_CTOR_INITIALIZERS:
  Error("attempt to read a C++ ctor initializer record as a declaration");
  return nullptr;
case DECL_IMPORT:
  // Note: last entry of the ImportDecl record is the number of stored source
  // locations.
  D = ImportDecl::CreateDeserialized(Context, ID, Record.back());
  break;
case DECL_OMP_THREADPRIVATE: {
  Record.skipInts(1);
  unsigned NumChildren = Record.readInt();
  Record.skipInts(1);
  D = OMPThreadPrivateDecl::CreateDeserialized(Context, ID, NumChildren);
  break;
}
case DECL_OMP_ALLOCATE: {
  unsigned NumClauses = Record.readInt();
  unsigned NumVars = Record.readInt();
  Record.skipInts(1);
  D = OMPAllocateDecl::CreateDeserialized(Context, ID, NumVars, NumClauses);
  break;
}
case DECL_OMP_REQUIRES: {
  unsigned NumClauses = Record.readInt();
  Record.skipInts(2);
  D = OMPRequiresDecl::CreateDeserialized(Context, ID, NumClauses);
  break;
}
case DECL_OMP_DECLARE_REDUCTION:
  D = OMPDeclareReductionDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OMP_DECLARE_MAPPER: {
  unsigned NumClauses = Record.readInt();
  Record.skipInts(2);
  D = OMPDeclareMapperDecl::CreateDeserialized(Context, ID, NumClauses);
  break;
}
case DECL_OMP_CAPTUREDEXPR:
  D = OMPCapturedExprDecl::CreateDeserialized(Context, ID);
  break;
case DECL_PRAGMA_COMMENT:
  D = PragmaCommentDecl::CreateDeserialized(Context, ID, Record.readInt());
  break;
case DECL_PRAGMA_DETECT_MISMATCH:
  D = PragmaDetectMismatchDecl::CreateDeserialized(Context, ID,
                                                   Record.readInt());
  break;
case DECL_EMPTY:
  D = EmptyDecl::CreateDeserialized(Context, ID);
  break;
case DECL_LIFETIME_EXTENDED_TEMPORARY:
  D = LifetimeExtendedTemporaryDecl::CreateDeserialized(Context, ID);
  break;
case DECL_OBJC_TYPE_PARAM:
  D = ObjCTypeParamDecl::CreateDeserialized(Context, ID);
  break;
}

assert(D && "Unknown declaration reading AST file")((void)0);
LoadedDecl(Index, D);
// Set the DeclContext before doing any deserialization, to make sure internal
// calls to Decl::getASTContext() by Decl's methods will find the
// TranslationUnitDecl without crashing.
D->setDeclContext(Context.getTranslationUnitDecl());
Reader.Visit(D);

// If this declaration is also a declaration context, get the
// offsets for its tables of lexical and visible declarations.
if (auto *DC = dyn_cast<DeclContext>(D)) {
  std::pair<uint64_t, uint64_t> Offsets = Reader.VisitDeclContext(DC);
  if (Offsets.first &&
      ReadLexicalDeclContextStorage(*Loc.F, DeclsCursor, Offsets.first, DC))
    return nullptr;
  if (Offsets.second &&
      ReadVisibleDeclContextStorage(*Loc.F, DeclsCursor, Offsets.second, ID))
    return nullptr;
}
assert(Record.getIdx() == Record.size())((void)0);

// Load any relevant update records.
PendingUpdateRecords.push_back(
    PendingUpdateRecord(ID, D, /*JustLoaded=*/true));

// Load the categories after recursive loading is finished.
if (auto *Class = dyn_cast<ObjCInterfaceDecl>(D))
  // If we already have a definition when deserializing the ObjCInterfaceDecl,
  // we put the Decl in PendingDefinitions so we can pull the categories here.
  if (Class->isThisDeclarationADefinition() ||
      PendingDefinitions.count(Class))
    loadObjCCategories(ID, Class);

// If we have deserialized a declaration that has a definition the
// AST consumer might need to know about, queue it.
// We don't pass it to the consumer immediately because we may be in recursive
// loading, and some declarations may still be initializing.
PotentiallyInterestingDecls.push_back(
    InterestingDecl(D, Reader.hasPendingBody()));

return D;
4149}

4151void ASTReader::PassInterestingDeclsToConsumer() {
assert(Consumer)((void)0);

if (PassingDeclsToConsumer)
  return;

// Guard variable to avoid recursively redoing the process of passing
// decls to consumer.
SaveAndRestore<bool> GuardPassingDeclsToConsumer(PassingDeclsToConsumer,
                                                 true);

// Ensure that we've loaded all potentially-interesting declarations
// that need to be eagerly loaded.
for (auto ID : EagerlyDeserializedDecls)
  GetDecl(ID);
EagerlyDeserializedDecls.clear();

while (!PotentiallyInterestingDecls.empty()) {
  InterestingDecl D = PotentiallyInterestingDecls.front();
  PotentiallyInterestingDecls.pop_front();
  if (isConsumerInterestedIn(getContext(), D.getDecl(), D.hasPendingBody()))
    PassInterestingDeclToConsumer(D.getDecl());
}
4174}

4176void ASTReader::loadDeclUpdateRecords(PendingUpdateRecord &Record) {
// The declaration may have been modified by files later in the chain.
// If this is the case, read the record containing the updates from each file
// and pass it to ASTDeclReader to make the modifications.
serialization::GlobalDeclID ID = Record.ID;
Decl *D = Record.D;
ProcessingUpdatesRAIIObj ProcessingUpdates(*this);
DeclUpdateOffsetsMap::iterator UpdI = DeclUpdateOffsets.find(ID);

SmallVector<serialization::DeclID, 8> PendingLazySpecializationIDs;

if (UpdI != DeclUpdateOffsets.end()) {
  auto UpdateOffsets = std::move(UpdI->second);
  DeclUpdateOffsets.erase(UpdI);

  // Check if this decl was interesting to the consumer. If we just loaded
  // the declaration, then we know it was interesting and we skip the call
  // to isConsumerInterestedIn because it is unsafe to call in the
  // current ASTReader state.
  bool WasInteresting =
      Record.JustLoaded || isConsumerInterestedIn(getContext(), D, false);
  for (auto &FileAndOffset : UpdateOffsets) {
    ModuleFile *F = FileAndOffset.first;
    uint64_t Offset = FileAndOffset.second;
    llvm::BitstreamCursor &Cursor = F->DeclsCursor;
    SavedStreamPosition SavedPosition(Cursor);
    if (llvm::Error JumpFailed = Cursor.JumpToBit(Offset))
      // FIXME don't do a fatal error.
      llvm::report_fatal_error(
          "ASTReader::loadDeclUpdateRecords failed jumping: " +
          toString(std::move(JumpFailed)));
    Expected<unsigned> MaybeCode = Cursor.ReadCode();
    if (!MaybeCode)
      llvm::report_fatal_error(
          "ASTReader::loadDeclUpdateRecords failed reading code: " +
          toString(MaybeCode.takeError()));
    unsigned Code = MaybeCode.get();
    ASTRecordReader Record(*this, *F);
    if (Expected<unsigned> MaybeRecCode = Record.readRecord(Cursor, Code))
      assert(MaybeRecCode.get() == DECL_UPDATES &&((void)0)
             "Expected DECL_UPDATES record!")((void)0);
    else
      llvm::report_fatal_error(
          "ASTReader::loadDeclUpdateRecords failed reading rec code: " +
          toString(MaybeCode.takeError()));

    ASTDeclReader Reader(*this, Record, RecordLocation(F, Offset), ID,
                         SourceLocation());
    Reader.UpdateDecl(D, PendingLazySpecializationIDs);

    // We might have made this declaration interesting. If so, remember that
    // we need to hand it off to the consumer.
    if (!WasInteresting &&
        isConsumerInterestedIn(getContext(), D, Reader.hasPendingBody())) {
      PotentiallyInterestingDecls.push_back(
          InterestingDecl(D, Reader.hasPendingBody()));
      WasInteresting = true;
    }
  }
}
// Add the lazy specializations to the template.
assert((PendingLazySpecializationIDs.empty() || isa<ClassTemplateDecl>(D) ||((void)0)
        isa<FunctionTemplateDecl>(D) || isa<VarTemplateDecl>(D)) &&((void)0)
       "Must not have pending specializations")((void)0);
if (auto *CTD = dyn_cast<ClassTemplateDecl>(D))
  ASTDeclReader::AddLazySpecializations(CTD, PendingLazySpecializationIDs);
else if (auto *FTD = dyn_cast<FunctionTemplateDecl>(D))
  ASTDeclReader::AddLazySpecializations(FTD, PendingLazySpecializationIDs);
else if (auto *VTD = dyn_cast<VarTemplateDecl>(D))
  ASTDeclReader::AddLazySpecializations(VTD, PendingLazySpecializationIDs);
PendingLazySpecializationIDs.clear();

// Load the pending visible updates for this decl context, if it has any.
auto I = PendingVisibleUpdates.find(ID);
if (I != PendingVisibleUpdates.end()) {
  auto VisibleUpdates = std::move(I->second);
  PendingVisibleUpdates.erase(I);

  auto *DC = cast<DeclContext>(D)->getPrimaryContext();
  for (const auto &Update : VisibleUpdates)
    Lookups[DC].Table.add(
        Update.Mod, Update.Data,
        reader::ASTDeclContextNameLookupTrait(*this, *Update.Mod));
  DC->setHasExternalVisibleStorage(true);
}
4261}

4263void ASTReader::loadPendingDeclChain(Decl *FirstLocal, uint64_t LocalOffset) {
// Attach FirstLocal to the end of the decl chain.
Decl *CanonDecl = FirstLocal->getCanonicalDecl();
if (FirstLocal != CanonDecl) {
  Decl *PrevMostRecent = ASTDeclReader::getMostRecentDecl(CanonDecl);
  ASTDeclReader::attachPreviousDecl(
      *this, FirstLocal, PrevMostRecent ? PrevMostRecent : CanonDecl,
      CanonDecl);
}

if (!LocalOffset) {
  ASTDeclReader::attachLatestDecl(CanonDecl, FirstLocal);
  return;
}

// Load the list of other redeclarations from this module file.
ModuleFile *M = getOwningModuleFile(FirstLocal);
assert(M && "imported decl from no module file")((void)0);

llvm::BitstreamCursor &Cursor = M->DeclsCursor;
SavedStreamPosition SavedPosition(Cursor);
if (llvm::Error JumpFailed = Cursor.JumpToBit(LocalOffset))
  llvm::report_fatal_error(
      "ASTReader::loadPendingDeclChain failed jumping: " +
      toString(std::move(JumpFailed)));

RecordData Record;
Expected<unsigned> MaybeCode = Cursor.ReadCode();
if (!MaybeCode)
  llvm::report_fatal_error(
      "ASTReader::loadPendingDeclChain failed reading code: " +
      toString(MaybeCode.takeError()));
unsigned Code = MaybeCode.get();
if (Expected<unsigned> MaybeRecCode = Cursor.readRecord(Code, Record))
  assert(MaybeRecCode.get() == LOCAL_REDECLARATIONS &&((void)0)
         "expected LOCAL_REDECLARATIONS record!")((void)0);
else
  llvm::report_fatal_error(
      "ASTReader::loadPendingDeclChain failed reading rec code: " +
      toString(MaybeCode.takeError()));

// FIXME: We have several different dispatches on decl kind here; maybe
// we should instead generate one loop per kind and dispatch up-front?
Decl *MostRecent = FirstLocal;
for (unsigned I = 0, N = Record.size(); I != N; ++I) {
  auto *D = GetLocalDecl(*M, Record[N - I - 1]);
  ASTDeclReader::attachPreviousDecl(*this, D, MostRecent, CanonDecl);
  MostRecent = D;
}
ASTDeclReader::attachLatestDecl(CanonDecl, MostRecent);
4313}

4315namespace {

/// Given an ObjC interface, goes through the modules and links to the
/// interface all the categories for it.
class ObjCCategoriesVisitor {
  ASTReader &Reader;
  ObjCInterfaceDecl *Interface;
  llvm::SmallPtrSetImpl<ObjCCategoryDecl *> &Deserialized;
  ObjCCategoryDecl *Tail = nullptr;
  llvm::DenseMap<DeclarationName, ObjCCategoryDecl *> NameCategoryMap;
  serialization::GlobalDeclID InterfaceID;
  unsigned PreviousGeneration;

  void add(ObjCCategoryDecl *Cat) {
    // Only process each category once.
    if (!Deserialized.erase(Cat))
      return;

    // Check for duplicate categories.
    if (Cat->getDeclName()) {
      ObjCCategoryDecl *&Existing = NameCategoryMap[Cat->getDeclName()];
      if (Existing &&
          Reader.getOwningModuleFile(Existing)
                                        != Reader.getOwningModuleFile(Cat)) {
        // FIXME: We should not warn for duplicates in diamond:
        //
        //   MT     //
        //  /  \    //
        // ML  MR   //
        //  \  /    //
        //   MB     //
        //
        // If there are duplicates in ML/MR, there will be warning when
        // creating MB *and* when importing MB. We should not warn when
        // importing.
        Reader.Diag(Cat->getLocation(), diag::warn_dup_category_def)
          << Interface->getDeclName() << Cat->getDeclName();
        Reader.Diag(Existing->getLocation(), diag::note_previous_definition);
      } else if (!Existing) {
        // Record this category.
        Existing = Cat;
      }
    }

    // Add this category to the end of the chain.
    if (Tail)
      ASTDeclReader::setNextObjCCategory(Tail, Cat);
    else
      Interface->setCategoryListRaw(Cat);
    Tail = Cat;
  }

public:
  ObjCCategoriesVisitor(ASTReader &Reader,
                        ObjCInterfaceDecl *Interface,
                        llvm::SmallPtrSetImpl<ObjCCategoryDecl *> &Deserialized,
                        serialization::GlobalDeclID InterfaceID,
                        unsigned PreviousGeneration)
      : Reader(Reader), Interface(Interface), Deserialized(Deserialized),
        InterfaceID(InterfaceID), PreviousGeneration(PreviousGeneration) {
    // Populate the name -> category map with the set of known categories.
    for (auto *Cat : Interface->known_categories()) {
      if (Cat->getDeclName())
        NameCategoryMap[Cat->getDeclName()] = Cat;

      // Keep track of the tail of the category list.
      Tail = Cat;
    }
  }

  bool operator()(ModuleFile &M) {
    // If we've loaded all of the category information we care about from
    // this module file, we're done.
    if (M.Generation <= PreviousGeneration)
      return true;

    // Map global ID of the definition down to the local ID used in this
    // module file. If there is no such mapping, we'll find nothing here
    // (or in any module it imports).
    DeclID LocalID = Reader.mapGlobalIDToModuleFileGlobalID(M, InterfaceID);
    if (!LocalID)
      return true;

    // Perform a binary search to find the local redeclarations for this
    // declaration (if any).
    const ObjCCategoriesInfo Compare = { LocalID, 0 };
    const ObjCCategoriesInfo *Result
      = std::lower_bound(M.ObjCCategoriesMap,
                         M.ObjCCategoriesMap + M.LocalNumObjCCategoriesInMap,
                         Compare);
    if (Result == M.ObjCCategoriesMap + M.LocalNumObjCCategoriesInMap ||
        Result->DefinitionID != LocalID) {
      // We didn't find anything. If the class definition is in this module
      // file, then the module files it depends on cannot have any categories,
      // so suppress further lookup.
      return Reader.isDeclIDFromModule(InterfaceID, M);
    }

    // We found something. Dig out all of the categories.
    unsigned Offset = Result->Offset;
    unsigned N = M.ObjCCategories[Offset];
    M.ObjCCategories[Offset++] = 0; // Don't try to deserialize again
    for (unsigned I = 0; I != N; ++I)
      add(cast_or_null<ObjCCategoryDecl>(
            Reader.GetLocalDecl(M, M.ObjCCategories[Offset++])));
    return true;
  }
};

4424} // namespace

4426void ASTReader::loadObjCCategories(serialization::GlobalDeclID ID,
                                 ObjCInterfaceDecl *D,
                                 unsigned PreviousGeneration) {
ObjCCategoriesVisitor Visitor(*this, D, CategoriesDeserialized, ID,
                              PreviousGeneration);
ModuleMgr.visit(Visitor);
4432}

4434template<typename DeclT, typename Fn>
4435static void forAllLaterRedecls(DeclT *D, Fn F) {
F(D);

// Check whether we've already merged D into its redeclaration chain.
// MostRecent may or may not be nullptr if D has not been merged. If
// not, walk the merged redecl chain and see if it's there.
auto *MostRecent = D->getMostRecentDecl();
bool Found = false;
for (auto *Redecl = MostRecent; Redecl && !Found;
     Redecl = Redecl->getPreviousDecl())
  Found = (Redecl == D);

// If this declaration is merged, apply the functor to all later decls.
if (Found) {
  for (auto *Redecl = MostRecent; Redecl != D;
       Redecl = Redecl->getPreviousDecl())
    F(Redecl);
}
4453}

4455void ASTDeclReader::UpdateDecl(Decl *D,
 llvm::SmallVectorImpl<serialization::DeclID> &PendingLazySpecializationIDs) {
while (Record.getIdx() < Record.size()) {
  switch ((DeclUpdateKind)Record.readInt()) {
  case UPD_CXX_ADDED_IMPLICIT_MEMBER: {
    auto *RD = cast<CXXRecordDecl>(D);
    // FIXME: If we also have an update record for instantiating the
    // definition of D, we need that to happen before we get here.
    Decl *MD = Record.readDecl();
    assert(MD && "couldn't read decl from update record")((void)0);
    // FIXME: We should call addHiddenDecl instead, to add the member
    // to its DeclContext.
    RD->addedMember(MD);
    break;
  }

  case UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION:
    // It will be added to the template's lazy specialization set.
    PendingLazySpecializationIDs.push_back(readDeclID());
    break;

  case UPD_CXX_ADDED_ANONYMOUS_NAMESPACE: {
    auto *Anon = readDeclAs<NamespaceDecl>();

    // Each module has its own anonymous namespace, which is disjoint from
    // any other module's anonymous namespaces, so don't attach the anonymous
    // namespace at all.
    if (!Record.isModule()) {
      if (auto *TU = dyn_cast<TranslationUnitDecl>(D))
        TU->setAnonymousNamespace(Anon);
      else
        cast<NamespaceDecl>(D)->setAnonymousNamespace(Anon);
    }
    break;
  }

  case UPD_CXX_ADDED_VAR_DEFINITION: {
    auto *VD = cast<VarDecl>(D);
    VD->NonParmVarDeclBits.IsInline = Record.readInt();
    VD->NonParmVarDeclBits.IsInlineSpecified = Record.readInt();
    uint64_t Val = Record.readInt();
    if (Val && !VD->getInit()) {
      VD->setInit(Record.readExpr());
      if (Val != 1) {
        EvaluatedStmt *Eval = VD->ensureEvaluatedStmt();
        Eval->HasConstantInitialization = (Val & 2) != 0;
        Eval->HasConstantDestruction = (Val & 4) != 0;
      }
    }
    break;
  }

  case UPD_CXX_POINT_OF_INSTANTIATION: {
    SourceLocation POI = Record.readSourceLocation();
    if (auto *VTSD = dyn_cast<VarTemplateSpecializationDecl>(D)) {
      VTSD->setPointOfInstantiation(POI);
    } else if (auto *VD = dyn_cast<VarDecl>(D)) {
      VD->getMemberSpecializationInfo()->setPointOfInstantiation(POI);
    } else {
      auto *FD = cast<FunctionDecl>(D);
      if (auto *FTSInfo = FD->TemplateOrSpecialization
                  .dyn_cast<FunctionTemplateSpecializationInfo *>())
        FTSInfo->setPointOfInstantiation(POI);
      else
        FD->TemplateOrSpecialization.get<MemberSpecializationInfo *>()
            ->setPointOfInstantiation(POI);
    }
    break;
  }

  case UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT: {
    auto *Param = cast<ParmVarDecl>(D);

    // We have to read the default argument regardless of whether we use it
    // so that hypothetical further update records aren't messed up.
    // TODO: Add a function to skip over the next expr record.
    auto *DefaultArg = Record.readExpr();

    // Only apply the update if the parameter still has an uninstantiated
    // default argument.
    if (Param->hasUninstantiatedDefaultArg())
      Param->setDefaultArg(DefaultArg);
    break;
  }

  case UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER: {
    auto *FD = cast<FieldDecl>(D);
    auto *DefaultInit = Record.readExpr();

    // Only apply the update if the field still has an uninstantiated
    // default member initializer.
    if (FD->hasInClassInitializer() && !FD->getInClassInitializer()) {
      if (DefaultInit)
        FD->setInClassInitializer(DefaultInit);
      else
        // Instantiation failed. We can get here if we serialized an AST for
        // an invalid program.
        FD->removeInClassInitializer();
    }
    break;
  }

  case UPD_CXX_ADDED_FUNCTION_DEFINITION: {
    auto *FD = cast<FunctionDecl>(D);
    if (Reader.PendingBodies[FD]) {
      // FIXME: Maybe check for ODR violations.
      // It's safe to stop now because this update record is always last.
      return;
    }

    if (Record.readInt()) {
      // Maintain AST consistency: any later redeclarations of this function
      // are inline if this one is. (We might have merged another declaration
      // into this one.)
      forAllLaterRedecls(FD, [](FunctionDecl *FD) {
        FD->setImplicitlyInline();
      });
    }
    FD->setInnerLocStart(readSourceLocation());
    ReadFunctionDefinition(FD);
    assert(Record.getIdx() == Record.size() && "lazy body must be last")((void)0);
    break;
  }

  case UPD_CXX_INSTANTIATED_CLASS_DEFINITION: {
    auto *RD = cast<CXXRecordDecl>(D);
    auto *OldDD = RD->getCanonicalDecl()->DefinitionData;
    bool HadRealDefinition =
        OldDD && (OldDD->Definition != RD ||
                  !Reader.PendingFakeDefinitionData.count(OldDD));
    RD->setParamDestroyedInCallee(Record.readInt());
    RD->setArgPassingRestrictions(
        (RecordDecl::ArgPassingKind)Record.readInt());
    ReadCXXRecordDefinition(RD, /*Update*/true);

    // Visible update is handled separately.
    uint64_t LexicalOffset = ReadLocalOffset();
    if (!HadRealDefinition && LexicalOffset) {
      Record.readLexicalDeclContextStorage(LexicalOffset, RD);
      Reader.PendingFakeDefinitionData.erase(OldDD);
    }

    auto TSK = (TemplateSpecializationKind)Record.readInt();
    SourceLocation POI = readSourceLocation();
    if (MemberSpecializationInfo *MSInfo =
            RD->getMemberSpecializationInfo()) {
      MSInfo->setTemplateSpecializationKind(TSK);
      MSInfo->setPointOfInstantiation(POI);
    } else {
      auto *Spec = cast<ClassTemplateSpecializationDecl>(RD);
      Spec->setTemplateSpecializationKind(TSK);
      Spec->setPointOfInstantiation(POI);

      if (Record.readInt()) {
        auto *PartialSpec =
            readDeclAs<ClassTemplatePartialSpecializationDecl>();
        SmallVector<TemplateArgument, 8> TemplArgs;
        Record.readTemplateArgumentList(TemplArgs);
        auto *TemplArgList = TemplateArgumentList::CreateCopy(
            Reader.getContext(), TemplArgs);

        // FIXME: If we already have a partial specialization set,
        // check that it matches.
        if (!Spec->getSpecializedTemplateOrPartial()
                 .is<ClassTemplatePartialSpecializationDecl *>())
          Spec->setInstantiationOf(PartialSpec, TemplArgList);
      }
    }

    RD->setTagKind((TagTypeKind)Record.readInt());
    RD->setLocation(readSourceLocation());
    RD->setLocStart(readSourceLocation());
    RD->setBraceRange(readSourceRange());

    if (Record.readInt()) {
      AttrVec Attrs;
      Record.readAttributes(Attrs);
      // If the declaration already has attributes, we assume that some other
      // AST file already loaded them.
      if (!D->hasAttrs())
        D->setAttrsImpl(Attrs, Reader.getContext());
    }
    break;
  }

  case UPD_CXX_RESOLVED_DTOR_DELETE: {
    // Set the 'operator delete' directly to avoid emitting another update
    // record.
    auto *Del = readDeclAs<FunctionDecl>();
    auto *First = cast<CXXDestructorDecl>(D->getCanonicalDecl());
    auto *ThisArg = Record.readExpr();
    // FIXME: Check consistency if we have an old and new operator delete.
    if (!First->OperatorDelete) {
      First->OperatorDelete = Del;
      First->OperatorDeleteThisArg = ThisArg;
    }
    break;
  }

  case UPD_CXX_RESOLVED_EXCEPTION_SPEC: {
    SmallVector<QualType, 8> ExceptionStorage;
    auto ESI = Record.readExceptionSpecInfo(ExceptionStorage);

    // Update this declaration's exception specification, if needed.
    auto *FD = cast<FunctionDecl>(D);
    auto *FPT = FD->getType()->castAs<FunctionProtoType>();
    // FIXME: If the exception specification is already present, check that it
    // matches.
    if (isUnresolvedExceptionSpec(FPT->getExceptionSpecType())) {
      FD->setType(Reader.getContext().getFunctionType(
          FPT->getReturnType(), FPT->getParamTypes(),
          FPT->getExtProtoInfo().withExceptionSpec(ESI)));

      // When we get to the end of deserializing, see if there are other decls
      // that we need to propagate this exception specification onto.
      Reader.PendingExceptionSpecUpdates.insert(
          std::make_pair(FD->getCanonicalDecl(), FD));
    }
    break;
  }

  case UPD_CXX_DEDUCED_RETURN_TYPE: {
    auto *FD = cast<FunctionDecl>(D);
    QualType DeducedResultType = Record.readType();
    Reader.PendingDeducedTypeUpdates.insert(
        {FD->getCanonicalDecl(), DeducedResultType});
    break;
  }

  case UPD_DECL_MARKED_USED:
    // Maintain AST consistency: any later redeclarations are used too.
    D->markUsed(Reader.getContext());
    break;

  case UPD_MANGLING_NUMBER:
    Reader.getContext().setManglingNumber(cast<NamedDecl>(D),
                                          Record.readInt());
    break;

  case UPD_STATIC_LOCAL_NUMBER:
    Reader.getContext().setStaticLocalNumber(cast<VarDecl>(D),
                                             Record.readInt());
    break;

  case UPD_DECL_MARKED_OPENMP_THREADPRIVATE:
    D->addAttr(OMPThreadPrivateDeclAttr::CreateImplicit(
        Reader.getContext(), readSourceRange(),
        AttributeCommonInfo::AS_Pragma));
    break;

  case UPD_DECL_MARKED_OPENMP_ALLOCATE: {
    auto AllocatorKind =
        static_cast<OMPAllocateDeclAttr::AllocatorTypeTy>(Record.readInt());
    Expr *Allocator = Record.readExpr();
    SourceRange SR = readSourceRange();
    D->addAttr(OMPAllocateDeclAttr::CreateImplicit(
        Reader.getContext(), AllocatorKind, Allocator, SR,
        AttributeCommonInfo::AS_Pragma));
    break;
  }

  case UPD_DECL_EXPORTED: {
    unsigned SubmoduleID = readSubmoduleID();
    auto *Exported = cast<NamedDecl>(D);
    Module *Owner = SubmoduleID ? Reader.getSubmodule(SubmoduleID) : nullptr;
    Reader.getContext().mergeDefinitionIntoModule(Exported, Owner);
    Reader.PendingMergedDefinitionsToDeduplicate.insert(Exported);
    break;
  }

  case UPD_DECL_MARKED_OPENMP_DECLARETARGET: {
    auto MapType = Record.readEnum<OMPDeclareTargetDeclAttr::MapTypeTy>();
    auto DevType = Record.readEnum<OMPDeclareTargetDeclAttr::DevTypeTy>();
    unsigned Level = Record.readInt();
    D->addAttr(OMPDeclareTargetDeclAttr::CreateImplicit(
        Reader.getContext(), MapType, DevType, Level, readSourceRange(),
        AttributeCommonInfo::AS_Pragma));
    break;
  }

  case UPD_ADDED_ATTR_TO_RECORD:
    AttrVec Attrs;
    Record.readAttributes(Attrs);
    assert(Attrs.size() == 1)((void)0);
    D->addAttr(Attrs[0]);
    break;
  }
}
4743}