Vendor import of clang trunk r238337:vendor/clang/clang-trunk-r238337

https://llvm.org/svn/llvm-project/cfe/trunk@238337

31 files changed, 3072 insertions, 1153 deletions

diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index c9fb80ceaae2..4a831d90e645 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -738,9 +738,9 @@ ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
       FILEDecl(nullptr), jmp_bufDecl(nullptr), sigjmp_bufDecl(nullptr),
       ucontext_tDecl(nullptr), BlockDescriptorType(nullptr),
       BlockDescriptorExtendedType(nullptr), cudaConfigureCallDecl(nullptr),
-      FirstLocalImport(), LastLocalImport(),
+      FirstLocalImport(), LastLocalImport(), ExternCContext(nullptr),
       SourceMgr(SM), LangOpts(LOpts),
-      SanitizerBL(new SanitizerBlacklist(LangOpts.SanitizerBlacklistFile, SM)),
+      SanitizerBL(new SanitizerBlacklist(LangOpts.SanitizerBlacklistFiles, SM)),
       AddrSpaceMap(nullptr), Target(nullptr), PrintingPolicy(LOpts),
       Idents(idents), Selectors(sels), BuiltinInfo(builtins),
       DeclarationNames(*this), ExternalSource(nullptr), Listener(nullptr),
@@ -866,6 +866,38 @@ void ASTContext::PrintStats() const {
   BumpAlloc.PrintStats();
 }
 
+void ASTContext::mergeDefinitionIntoModule(NamedDecl *ND, Module *M,
+                                           bool NotifyListeners) {
+  if (NotifyListeners)
+    if (auto *Listener = getASTMutationListener())
+      Listener->RedefinedHiddenDefinition(ND, M);
+
+  if (getLangOpts().ModulesLocalVisibility)
+    MergedDefModules[ND].push_back(M);
+  else
+    ND->setHidden(false);
+}
+
+void ASTContext::deduplicateMergedDefinitonsFor(NamedDecl *ND) {
+  auto It = MergedDefModules.find(ND);
+  if (It == MergedDefModules.end())
+    return;
+
+  auto &Merged = It->second;
+  llvm::DenseSet<Module*> Found;
+  for (Module *&M : Merged)
+    if (!Found.insert(M).second)
+      M = nullptr;
+  Merged.erase(std::remove(Merged.begin(), Merged.end(), nullptr), Merged.end());
+}
+
+ExternCContextDecl *ASTContext::getExternCContextDecl() const {
+  if (!ExternCContext)
+    ExternCContext = ExternCContextDecl::Create(*this, getTranslationUnitDecl());
+
+  return ExternCContext;
+}
+
 RecordDecl *ASTContext::buildImplicitRecord(StringRef Name,
                                             RecordDecl::TagKind TK) const {
   SourceLocation Loc;
@@ -877,6 +909,8 @@ RecordDecl *ASTContext::buildImplicitRecord(StringRef Name,
     NewDecl = RecordDecl::Create(*this, TK, getTranslationUnitDecl(), Loc, Loc,
                                  &Idents.get(Name));
   NewDecl->setImplicit();
+  NewDecl->addAttr(TypeVisibilityAttr::CreateImplicit(
+      const_cast<ASTContext &>(*this), TypeVisibilityAttr::Default));
   return NewDecl;
 }
 
@@ -1326,7 +1360,7 @@ CharUnits ASTContext::getDeclAlign(const Decl *D, bool ForAlignof) const {
       }
       Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
       if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
-        if (VD->hasGlobalStorage())
+        if (VD->hasGlobalStorage() && !ForAlignof)
           Align = std::max(Align, getTargetInfo().getMinGlobalAlign());
       }
     }
@@ -1669,13 +1703,23 @@ TypeInfo ASTContext::getTypeInfoImpl(const Type *T) const {
       break;
     }
 
-    if (const EnumType *ET = dyn_cast<EnumType>(TT))
-      return getTypeInfo(ET->getDecl()->getIntegerType());
+    if (const EnumType *ET = dyn_cast<EnumType>(TT)) {
+      const EnumDecl *ED = ET->getDecl();
+      TypeInfo Info =
+          getTypeInfo(ED->getIntegerType()->getUnqualifiedDesugaredType());
+      if (unsigned AttrAlign = ED->getMaxAlignment()) {
+        Info.Align = AttrAlign;
+        Info.AlignIsRequired = true;
+      }
+      return Info;
+    }
 
     const RecordType *RT = cast<RecordType>(TT);
-    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
+    const RecordDecl *RD = RT->getDecl();
+    const ASTRecordLayout &Layout = getASTRecordLayout(RD);
     Width = toBits(Layout.getSize());
     Align = toBits(Layout.getAlignment());
+    AlignIsRequired = RD->hasAttr<AlignedAttr>();
     break;
   }
 
@@ -1778,13 +1822,20 @@ unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
   TypeInfo TI = getTypeInfo(T);
   unsigned ABIAlign = TI.Align;
 
+  T = T->getBaseElementTypeUnsafe();
+
+  // The preferred alignment of member pointers is that of a pointer.
+  if (T->isMemberPointerType())
+    return getPreferredTypeAlign(getPointerDiffType().getTypePtr());
+
   if (Target->getTriple().getArch() == llvm::Triple::xcore)
     return ABIAlign;  // Never overalign on XCore.
 
   // Double and long long should be naturally aligned if possible.
-  T = T->getBaseElementTypeUnsafe();
   if (const ComplexType *CT = T->getAs<ComplexType>())
     T = CT->getElementType().getTypePtr();
+  if (const EnumType *ET = T->getAs<EnumType>())
+    T = ET->getDecl()->getIntegerType().getTypePtr();
   if (T->isSpecificBuiltinType(BuiltinType::Double) ||
       T->isSpecificBuiltinType(BuiltinType::LongLong) ||
       T->isSpecificBuiltinType(BuiltinType::ULongLong))
@@ -1796,6 +1847,13 @@ unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
   return ABIAlign;
 }
 
+/// getTargetDefaultAlignForAttributeAligned - Return the default alignment
+/// for __attribute__((aligned)) on this target, to be used if no alignment
+/// value is specified.
+unsigned ASTContext::getTargetDefaultAlignForAttributeAligned(void) const {
+  return getTargetInfo().getDefaultAlignForAttributeAligned();
+}
+
 /// getAlignOfGlobalVar - Return the alignment in bits that should be given
 /// to a global variable of the specified type.
 unsigned ASTContext::getAlignOfGlobalVar(QualType T) const {
@@ -3337,7 +3395,7 @@ ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
     (void)CheckT;
   }
 
-  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
+  T = new (*this, TypeAlignment) ElaboratedType(Keyword, NNS, NamedType, Canon);
   Types.push_back(T);
   ElaboratedTypes.InsertNode(T, InsertPos);
   return QualType(T, 0);
@@ -3361,7 +3419,7 @@ ASTContext::getParenType(QualType InnerType) const {
     (void)CheckT;
   }
 
-  T = new (*this) ParenType(InnerType, Canon);
+  T = new (*this, TypeAlignment) ParenType(InnerType, Canon);
   Types.push_back(T);
   ParenTypes.InsertNode(T, InsertPos);
   return QualType(T, 0);
@@ -3390,7 +3448,7 @@ QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
   if (T)
     return QualType(T, 0);
 
-  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
+  T = new (*this, TypeAlignment) DependentNameType(Keyword, NNS, Name, Canon);
   Types.push_back(T);
   DependentNameTypes.InsertNode(T, InsertPos);
   return QualType(T, 0);
@@ -3492,7 +3550,8 @@ QualType ASTContext::getPackExpansionType(QualType Pattern,
     }
   }
 
-  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
+  T = new (*this, TypeAlignment)
+      PackExpansionType(Pattern, Canon, NumExpansions);
   Types.push_back(T);
   PackExpansionTypes.InsertNode(T, InsertPos);
   return QualType(T, 0);
@@ -3500,9 +3559,9 @@ QualType ASTContext::getPackExpansionType(QualType Pattern,
 
 /// CmpProtocolNames - Comparison predicate for sorting protocols
 /// alphabetically.
-static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
-                            const ObjCProtocolDecl *RHS) {
-  return LHS->getDeclName() < RHS->getDeclName();
+static int CmpProtocolNames(ObjCProtocolDecl *const *LHS,
+                            ObjCProtocolDecl *const *RHS) {
+  return DeclarationName::compare((*LHS)->getDeclName(), (*RHS)->getDeclName());
 }
 
 static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
@@ -3513,7 +3572,7 @@ static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
     return false;
   
   for (unsigned i = 1; i != NumProtocols; ++i)
-    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
+    if (CmpProtocolNames(&Protocols[i - 1], &Protocols[i]) >= 0 ||
         Protocols[i]->getCanonicalDecl() != Protocols[i])
       return false;
   return true;
@@ -3524,7 +3583,7 @@ static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
   ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
 
   // Sort protocols, keyed by name.
-  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
+  llvm::array_pod_sort(Protocols, ProtocolsEnd, CmpProtocolNames);
 
   // Canonicalize.
   for (unsigned I = 0, N = NumProtocols; I != N; ++I)
@@ -4325,6 +4384,19 @@ QualType ASTContext::getSignatureParameterType(QualType T) const {
   return T.getUnqualifiedType();
 }
 
+QualType ASTContext::getExceptionObjectType(QualType T) const {
+  // C++ [except.throw]p3:
+  //   A throw-expression initializes a temporary object, called the exception
+  //   object, the type of which is determined by removing any top-level
+  //   cv-qualifiers from the static type of the operand of throw and adjusting
+  //   the type from "array of T" or "function returning T" to "pointer to T"
+  //   or "pointer to function returning T", [...]
+  T = getVariableArrayDecayedType(T);
+  if (T->isArrayType() || T->isFunctionType())
+    T = getDecayedType(T);
+  return T.getUnqualifiedType();
+}
+
 /// getArrayDecayedType - Return the properly qualified result of decaying the
 /// specified array type to a pointer.  This operation is non-trivial when
 /// handling typedefs etc.  The canonical type of "T" must be an array type,
@@ -4859,7 +4931,7 @@ CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
 bool ASTContext::isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const {
   return getLangOpts().MSVCCompat && VD->isStaticDataMember() &&
          VD->getType()->isIntegralOrEnumerationType() &&
-         !VD->getFirstDecl()->isOutOfLine() && VD->getFirstDecl()->hasInit();
+         VD->isFirstDecl() && !VD->isOutOfLine() && VD->hasInit();
 }
 
 static inline 
@@ -7544,7 +7616,7 @@ static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
       break;
     case 'U':
       assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
-      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
+      assert(!Unsigned && "Can't use 'U' modifier multiple times!");
       Unsigned = true;
       break;
     case 'L':
@@ -7579,7 +7651,7 @@ static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
     break;
   case 'h':
     assert(HowLong == 0 && !Signed && !Unsigned &&
-           "Bad modifiers used with 'f'!");
+           "Bad modifiers used with 'h'!");
     Type = Context.HalfTy;
     break;
   case 'f':
@@ -7806,6 +7878,9 @@ QualType ASTContext::GetBuiltinType(unsigned Id,
     ArgTypes.push_back(Ty);
   }
 
+  if (Id == Builtin::BI__GetExceptionInfo)
+    return QualType();
+
   assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
          "'.' should only occur at end of builtin type list!");
 
@@ -7909,7 +7984,7 @@ static GVALinkage basicGVALinkageForVariable(const ASTContext &Context,
     while (LexicalContext && !isa<FunctionDecl>(LexicalContext))
       LexicalContext = LexicalContext->getLexicalParent();
 
-    // Let the static local variable inherit it's linkage from the nearest
+    // Let the static local variable inherit its linkage from the nearest
     // enclosing function.
     if (LexicalContext)
       StaticLocalLinkage =
@@ -8042,7 +8117,9 @@ CallingConv ASTContext::getDefaultCallingConvention(bool IsVariadic,
   if (IsCXXMethod)
     return ABI->getDefaultMethodCallConv(IsVariadic);
 
-  return (LangOpts.MRTD && !IsVariadic) ? CC_X86StdCall : CC_C;
+  if (LangOpts.MRTD && !IsVariadic) return CC_X86StdCall;
+
+  return Target->getDefaultCallingConv(TargetInfo::CCMT_Unknown);
 }
 
 bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
@@ -8161,6 +8238,31 @@ MangleNumberingContext *ASTContext::createMangleNumberingContext() const {
   return ABI->createMangleNumberingContext();
 }
 
+const CXXConstructorDecl *
+ASTContext::getCopyConstructorForExceptionObject(CXXRecordDecl *RD) {
+  return ABI->getCopyConstructorForExceptionObject(
+      cast<CXXRecordDecl>(RD->getFirstDecl()));
+}
+
+void ASTContext::addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
+                                                      CXXConstructorDecl *CD) {
+  return ABI->addCopyConstructorForExceptionObject(
+      cast<CXXRecordDecl>(RD->getFirstDecl()),
+      cast<CXXConstructorDecl>(CD->getFirstDecl()));
+}
+
+void ASTContext::addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                                 unsigned ParmIdx, Expr *DAE) {
+  ABI->addDefaultArgExprForConstructor(
+      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx, DAE);
+}
+
+Expr *ASTContext::getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                                  unsigned ParmIdx) {
+  return ABI->getDefaultArgExprForConstructor(
+      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx);
+}
+
 void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
   ParamIndices[D] = index;
 }
diff --git a/lib/AST/ASTDumper.cpp b/lib/AST/ASTDumper.cpp
index ebf5e651ef9a..60cbb0601138 100644
--- a/lib/AST/ASTDumper.cpp
+++ b/lib/AST/ASTDumper.cpp
@@ -508,6 +508,8 @@ namespace  {
     void VisitCXXFunctionalCastExpr(const CXXFunctionalCastExpr *Node);
     void VisitCXXConstructExpr(const CXXConstructExpr *Node);
     void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *Node);
+    void VisitCXXNewExpr(const CXXNewExpr *Node);
+    void VisitCXXDeleteExpr(const CXXDeleteExpr *Node);
     void VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *Node);
     void VisitExprWithCleanups(const ExprWithCleanups *Node);
     void VisitUnresolvedLookupExpr(const UnresolvedLookupExpr *Node);
@@ -516,6 +518,7 @@ namespace  {
       VisitExpr(Node);
       dumpDecl(Node->getLambdaClass());
     }
+    void VisitSizeOfPackExpr(const SizeOfPackExpr *Node);
 
     // ObjC
     void VisitObjCAtCatchStmt(const ObjCAtCatchStmt *Node);
@@ -974,8 +977,10 @@ void ASTDumper::dumpDecl(const Decl *D) {
     dumpSourceRange(D->getSourceRange());
     OS << ' ';
     dumpLocation(D->getLocation());
-    if (Module *M = D->getOwningModule())
+    if (Module *M = D->getImportedOwningModule())
       OS << " in " << M->getFullModuleName();
+    else if (Module *M = D->getLocalOwningModule())
+      OS << " in (local) " << M->getFullModuleName();
     if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
       if (ND->isHidden())
         OS << " hidden";
@@ -1099,10 +1104,13 @@ void ASTDumper::VisitFunctionDecl(const FunctionDecl *D) {
        E = D->getDeclsInPrototypeScope().end(); I != E; ++I)
     dumpDecl(*I);
 
-  for (FunctionDecl::param_const_iterator I = D->param_begin(),
-                                          E = D->param_end();
-       I != E; ++I)
-    dumpDecl(*I);
+  if (!D->param_begin() && D->getNumParams())
+    dumpChild([=] { OS << "<<NULL params x " << D->getNumParams() << ">>"; });
+  else
+    for (FunctionDecl::param_const_iterator I = D->param_begin(),
+                                            E = D->param_end();
+         I != E; ++I)
+      dumpDecl(*I);
 
   if (const CXXConstructorDecl *C = dyn_cast<CXXConstructorDecl>(D))
     for (CXXConstructorDecl::init_const_iterator I = C->init_begin(),
@@ -1913,6 +1921,32 @@ void ASTDumper::VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *Node) {
   dumpCXXTemporary(Node->getTemporary());
 }
 
+void ASTDumper::VisitCXXNewExpr(const CXXNewExpr *Node) {
+  VisitExpr(Node);
+  if (Node->isGlobalNew())
+    OS << " global";
+  if (Node->isArray())
+    OS << " array";
+  if (Node->getOperatorNew()) {
+    OS << ' ';
+    dumpBareDeclRef(Node->getOperatorNew());
+  }
+  // We could dump the deallocation function used in case of error, but it's
+  // usually not that interesting.
+}
+
+void ASTDumper::VisitCXXDeleteExpr(const CXXDeleteExpr *Node) {
+  VisitExpr(Node);
+  if (Node->isGlobalDelete())
+    OS << " global";
+  if (Node->isArrayForm())
+    OS << " array";
+  if (Node->getOperatorDelete()) {
+    OS << ' ';
+    dumpBareDeclRef(Node->getOperatorDelete());
+  }
+}
+
 void
 ASTDumper::VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *Node) {
   VisitExpr(Node);
@@ -1934,6 +1968,13 @@ void ASTDumper::dumpCXXTemporary(const CXXTemporary *Temporary) {
   OS << ")";
 }
 
+void ASTDumper::VisitSizeOfPackExpr(const SizeOfPackExpr *Node) {
+  VisitExpr(Node);
+  dumpPointer(Node->getPack());
+  dumpName(Node->getPack());
+}
+
+
 //===----------------------------------------------------------------------===//
 // Obj-C Expressions
 //===----------------------------------------------------------------------===//
@@ -2255,6 +2296,11 @@ LLVM_DUMP_METHOD void Stmt::dump(raw_ostream &OS, SourceManager &SM) const {
   P.dumpStmt(this);
 }
 
+LLVM_DUMP_METHOD void Stmt::dump(raw_ostream &OS) const {
+  ASTDumper P(OS, nullptr, nullptr);
+  P.dumpStmt(this);
+}
+
 LLVM_DUMP_METHOD void Stmt::dump() const {
   ASTDumper P(llvm::errs(), nullptr, nullptr);
   P.dumpStmt(this);
diff --git a/lib/AST/ASTImporter.cpp b/lib/AST/ASTImporter.cpp
index 2442e8ec25f1..911f1681ce61 100644
--- a/lib/AST/ASTImporter.cpp
+++ b/lib/AST/ASTImporter.cpp
@@ -67,6 +67,7 @@ namespace clang {
     // FIXME: DependentDecltypeType
     QualType VisitRecordType(const RecordType *T);
     QualType VisitEnumType(const EnumType *T);
+    QualType VisitAttributedType(const AttributedType *T);
     // FIXME: TemplateTypeParmType
     // FIXME: SubstTemplateTypeParmType
     QualType VisitTemplateSpecializationType(const TemplateSpecializationType *T);
@@ -80,7 +81,7 @@ namespace clang {
     // Importing declarations                            
     bool ImportDeclParts(NamedDecl *D, DeclContext *&DC, 
                          DeclContext *&LexicalDC, DeclarationName &Name, 
-                         SourceLocation &Loc);
+                         NamedDecl *&ToD, SourceLocation &Loc);
     void ImportDefinitionIfNeeded(Decl *FromD, Decl *ToD = nullptr);
     void ImportDeclarationNameLoc(const DeclarationNameInfo &From,
                                   DeclarationNameInfo& To);
@@ -167,7 +168,44 @@ namespace clang {
     Decl *VisitVarTemplateSpecializationDecl(VarTemplateSpecializationDecl *D);
 
     // Importing statements
+    DeclGroupRef ImportDeclGroup(DeclGroupRef DG);
+
     Stmt *VisitStmt(Stmt *S);
+    Stmt *VisitDeclStmt(DeclStmt *S);
+    Stmt *VisitNullStmt(NullStmt *S);
+    Stmt *VisitCompoundStmt(CompoundStmt *S);
+    Stmt *VisitCaseStmt(CaseStmt *S);
+    Stmt *VisitDefaultStmt(DefaultStmt *S);
+    Stmt *VisitLabelStmt(LabelStmt *S);
+    Stmt *VisitAttributedStmt(AttributedStmt *S);
+    Stmt *VisitIfStmt(IfStmt *S);
+    Stmt *VisitSwitchStmt(SwitchStmt *S);
+    Stmt *VisitWhileStmt(WhileStmt *S);
+    Stmt *VisitDoStmt(DoStmt *S);
+    Stmt *VisitForStmt(ForStmt *S);
+    Stmt *VisitGotoStmt(GotoStmt *S);
+    Stmt *VisitIndirectGotoStmt(IndirectGotoStmt *S);
+    Stmt *VisitContinueStmt(ContinueStmt *S);
+    Stmt *VisitBreakStmt(BreakStmt *S);
+    Stmt *VisitReturnStmt(ReturnStmt *S);
+    // FIXME: GCCAsmStmt
+    // FIXME: MSAsmStmt
+    // FIXME: SEHExceptStmt
+    // FIXME: SEHFinallyStmt
+    // FIXME: SEHTryStmt
+    // FIXME: SEHLeaveStmt
+    // FIXME: CapturedStmt
+    Stmt *VisitCXXCatchStmt(CXXCatchStmt *S);
+    Stmt *VisitCXXTryStmt(CXXTryStmt *S);
+    Stmt *VisitCXXForRangeStmt(CXXForRangeStmt *S);
+    // FIXME: MSDependentExistsStmt
+    Stmt *VisitObjCForCollectionStmt(ObjCForCollectionStmt *S);
+    Stmt *VisitObjCAtCatchStmt(ObjCAtCatchStmt *S);
+    Stmt *VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *S);
+    Stmt *VisitObjCAtTryStmt(ObjCAtTryStmt *S);
+    Stmt *VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S);
+    Stmt *VisitObjCAtThrowStmt(ObjCAtThrowStmt *S);
+    Stmt *VisitObjCAutoreleasePoolStmt(ObjCAutoreleasePoolStmt *S);
 
     // Importing expressions
     Expr *VisitExpr(Expr *E);
@@ -181,6 +219,9 @@ namespace clang {
     Expr *VisitCompoundAssignOperator(CompoundAssignOperator *E);
     Expr *VisitImplicitCastExpr(ImplicitCastExpr *E);
     Expr *VisitCStyleCastExpr(CStyleCastExpr *E);
+    Expr *VisitCXXConstructExpr(CXXConstructExpr *E);
+    Expr *VisitMemberExpr(MemberExpr *E);
+    Expr *VisitCallExpr(CallExpr *E);
   };
 }
 using namespace clang;
@@ -1724,6 +1765,27 @@ QualType ASTNodeImporter::VisitEnumType(const EnumType *T) {
   return Importer.getToContext().getTagDeclType(ToDecl);
 }
 
+QualType ASTNodeImporter::VisitAttributedType(const AttributedType *T) {
+  QualType FromModifiedType = T->getModifiedType();
+  QualType FromEquivalentType = T->getEquivalentType();
+  QualType ToModifiedType;
+  QualType ToEquivalentType;
+
+  if (!FromModifiedType.isNull()) {
+    ToModifiedType = Importer.Import(FromModifiedType);
+    if (ToModifiedType.isNull())
+      return QualType();
+  }
+  if (!FromEquivalentType.isNull()) {
+    ToEquivalentType = Importer.Import(FromEquivalentType);
+    if (ToEquivalentType.isNull())
+      return QualType();
+  }
+
+  return Importer.getToContext().getAttributedType(T->getAttrKind(),
+    ToModifiedType, ToEquivalentType);
+}
+
 QualType ASTNodeImporter::VisitTemplateSpecializationType(
                                        const TemplateSpecializationType *T) {
   TemplateName ToTemplate = Importer.Import(T->getTemplateName());
@@ -1808,6 +1870,7 @@ ASTNodeImporter::VisitObjCObjectPointerType(const ObjCObjectPointerType *T) {
 bool ASTNodeImporter::ImportDeclParts(NamedDecl *D, DeclContext *&DC, 
                                       DeclContext *&LexicalDC, 
                                       DeclarationName &Name, 
+                                      NamedDecl *&ToD,
                                       SourceLocation &Loc) {
   // Import the context of this declaration.
   DC = Importer.ImportContext(D->getDeclContext());
@@ -1828,6 +1891,7 @@ bool ASTNodeImporter::ImportDeclParts(NamedDecl *D, DeclContext *&DC,
   
   // Import the location of this declaration.
   Loc = Importer.Import(D->getLocation());
+  ToD = cast_or_null<NamedDecl>(Importer.GetAlreadyImportedOrNull(D));
   return false;
 }
 
@@ -2009,7 +2073,7 @@ bool ASTNodeImporter::ImportDefinition(RecordDecl *From, RecordDecl *To,
 
 bool ASTNodeImporter::ImportDefinition(VarDecl *From, VarDecl *To,
                                        ImportDefinitionKind Kind) {
-  if (To->getDefinition())
+  if (To->getAnyInitializer())
     return false;
 
   // FIXME: Can we really import any initializer? Alternatively, we could force
@@ -2239,8 +2303,11 @@ Decl *ASTNodeImporter::VisitNamespaceDecl(NamespaceDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   NamespaceDecl *MergeWithNamespace = nullptr;
   if (!Name) {
@@ -2307,8 +2374,11 @@ Decl *ASTNodeImporter::VisitTypedefNameDecl(TypedefNameDecl *D, bool IsAlias) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // If this typedef is not in block scope, determine whether we've
   // seen a typedef with the same name (that we can merge with) or any
@@ -2381,8 +2451,11 @@ Decl *ASTNodeImporter::VisitEnumDecl(EnumDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Figure out what enum name we're looking for.
   unsigned IDNS = Decl::IDNS_Tag;
@@ -2466,8 +2539,11 @@ Decl *ASTNodeImporter::VisitRecordDecl(RecordDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Figure out what structure name we're looking for.
   unsigned IDNS = Decl::IDNS_Tag;
@@ -2592,8 +2668,11 @@ Decl *ASTNodeImporter::VisitEnumConstantDecl(EnumConstantDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   QualType T = Importer.Import(D->getType());
   if (T.isNull())
@@ -2648,8 +2727,11 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Try to find a function in our own ("to") context with the same name, same
   // type, and in the same context as the function we're importing.
@@ -2741,10 +2823,11 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
   // Create the imported function.
   TypeSourceInfo *TInfo = Importer.Import(D->getTypeSourceInfo());
   FunctionDecl *ToFunction = nullptr;
+  SourceLocation InnerLocStart = Importer.Import(D->getInnerLocStart());
   if (CXXConstructorDecl *FromConstructor = dyn_cast<CXXConstructorDecl>(D)) {
     ToFunction = CXXConstructorDecl::Create(Importer.getToContext(),
                                             cast<CXXRecordDecl>(DC),
-                                            D->getInnerLocStart(),
+                                            InnerLocStart,
                                             NameInfo, T, TInfo, 
                                             FromConstructor->isExplicit(),
                                             D->isInlineSpecified(), 
@@ -2753,7 +2836,7 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
   } else if (isa<CXXDestructorDecl>(D)) {
     ToFunction = CXXDestructorDecl::Create(Importer.getToContext(),
                                            cast<CXXRecordDecl>(DC),
-                                           D->getInnerLocStart(),
+                                           InnerLocStart,
                                            NameInfo, T, TInfo,
                                            D->isInlineSpecified(),
                                            D->isImplicit());
@@ -2761,7 +2844,7 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
                                            = dyn_cast<CXXConversionDecl>(D)) {
     ToFunction = CXXConversionDecl::Create(Importer.getToContext(), 
                                            cast<CXXRecordDecl>(DC),
-                                           D->getInnerLocStart(),
+                                           InnerLocStart,
                                            NameInfo, T, TInfo,
                                            D->isInlineSpecified(),
                                            FromConversion->isExplicit(),
@@ -2770,7 +2853,7 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
   } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
     ToFunction = CXXMethodDecl::Create(Importer.getToContext(), 
                                        cast<CXXRecordDecl>(DC),
-                                       D->getInnerLocStart(),
+                                       InnerLocStart,
                                        NameInfo, T, TInfo,
                                        Method->getStorageClass(),
                                        Method->isInlineSpecified(),
@@ -2778,7 +2861,7 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
                                        Importer.Import(D->getLocEnd()));
   } else {
     ToFunction = FunctionDecl::Create(Importer.getToContext(), DC,
-                                      D->getInnerLocStart(),
+                                      InnerLocStart,
                                       NameInfo, T, TInfo, D->getStorageClass(),
                                       D->isInlineSpecified(),
                                       D->hasWrittenPrototype(),
@@ -2809,6 +2892,13 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
     ToFunction->setType(T);
   }
 
+  // Import the body, if any.
+  if (Stmt *FromBody = D->getBody()) {
+    if (Stmt *ToBody = Importer.Import(FromBody)) {
+      ToFunction->setBody(ToBody);
+    }
+  }
+
   // FIXME: Other bits to merge?
 
   // Add this function to the lexical context.
@@ -2855,8 +2945,11 @@ Decl *ASTNodeImporter::VisitFieldDecl(FieldDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Determine whether we've already imported this field. 
   SmallVector<NamedDecl *, 2> FoundDecls;
@@ -2911,8 +3004,11 @@ Decl *ASTNodeImporter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Determine whether we've already imported this field. 
   SmallVector<NamedDecl *, 2> FoundDecls;
@@ -2978,8 +3074,11 @@ Decl *ASTNodeImporter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Determine whether we've already imported this ivar 
   SmallVector<NamedDecl *, 2> FoundDecls;
@@ -3028,8 +3127,11 @@ Decl *ASTNodeImporter::VisitVarDecl(VarDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Try to find a variable in our own ("to") context with the same name and
   // in the same context as the variable we're importing.
@@ -3137,6 +3239,10 @@ Decl *ASTNodeImporter::VisitVarDecl(VarDecl *D) {
   Importer.Imported(D, ToVar);
   LexicalDC->addDeclInternal(ToVar);
 
+  if (!D->isFileVarDecl() &&
+      D->isUsed())
+    ToVar->setIsUsed();
+
   // Merge the initializer.
   if (ImportDefinition(D, ToVar))
     return nullptr;
@@ -3196,6 +3302,10 @@ Decl *ASTNodeImporter::VisitParmVarDecl(ParmVarDecl *D) {
                                             T, TInfo, D->getStorageClass(),
                                             /*FIXME: Default argument*/nullptr);
   ToParm->setHasInheritedDefaultArg(D->hasInheritedDefaultArg());
+
+  if (D->isUsed())
+    ToParm->setIsUsed();
+
   return Importer.Imported(D, ToParm);
 }
 
@@ -3204,8 +3314,11 @@ Decl *ASTNodeImporter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   SmallVector<NamedDecl *, 2> FoundDecls;
   DC->getRedeclContext()->localUncachedLookup(Name, FoundDecls);
@@ -3315,8 +3428,11 @@ Decl *ASTNodeImporter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   ObjCInterfaceDecl *ToInterface
     = cast_or_null<ObjCInterfaceDecl>(Importer.Import(D->getClassInterface()));
@@ -3439,8 +3555,11 @@ Decl *ASTNodeImporter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   ObjCProtocolDecl *MergeWithProtocol = nullptr;
   SmallVector<NamedDecl *, 2> FoundDecls;
@@ -3614,8 +3733,11 @@ Decl *ASTNodeImporter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Look for an existing interface with the same name.
   ObjCInterfaceDecl *MergeWithIface = nullptr;
@@ -3769,8 +3891,11 @@ Decl *ASTNodeImporter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // Check whether we have already imported this property.
   SmallVector<NamedDecl *, 2> FoundDecls;
@@ -4000,8 +4125,11 @@ Decl *ASTNodeImporter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // We may already have a template of the same name; try to find and match it.
   if (!DC->isFunctionOrMethod()) {
@@ -4188,8 +4316,11 @@ Decl *ASTNodeImporter::VisitVarTemplateDecl(VarTemplateDecl *D) {
   DeclContext *DC, *LexicalDC;
   DeclarationName Name;
   SourceLocation Loc;
-  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
+  NamedDecl *ToD;
+  if (ImportDeclParts(D, DC, LexicalDC, Name, ToD, Loc))
     return nullptr;
+  if (ToD)
+    return ToD;
 
   // We may already have a template of the same name; try to find and match it.
   assert(!DC->isFunctionOrMethod() &&
@@ -4371,10 +4502,457 @@ Decl *ASTNodeImporter::VisitVarTemplateSpecializationDecl(
 // Import Statements
 //----------------------------------------------------------------------------
 
-Stmt *ASTNodeImporter::VisitStmt(Stmt *S) {
-  Importer.FromDiag(S->getLocStart(), diag::err_unsupported_ast_node)
-    << S->getStmtClassName();
-  return nullptr;
+DeclGroupRef ASTNodeImporter::ImportDeclGroup(DeclGroupRef DG) {
+  if (DG.isNull())
+    return DeclGroupRef::Create(Importer.getToContext(), nullptr, 0);
+  size_t NumDecls = DG.end() - DG.begin();
+  SmallVector<Decl *, 1> ToDecls(NumDecls);
+  auto &_Importer = this->Importer;
+  std::transform(DG.begin(), DG.end(), ToDecls.begin(),
+    [&_Importer](Decl *D) -> Decl * {
+      return _Importer.Import(D);
+    });
+  return DeclGroupRef::Create(Importer.getToContext(),
+                              ToDecls.begin(),
+                              NumDecls);
+}
+
+ Stmt *ASTNodeImporter::VisitStmt(Stmt *S) {
+   Importer.FromDiag(S->getLocStart(), diag::err_unsupported_ast_node)
+     << S->getStmtClassName();
+   return nullptr;
+ }
+ 
+Stmt *ASTNodeImporter::VisitDeclStmt(DeclStmt *S) {
+  DeclGroupRef ToDG = ImportDeclGroup(S->getDeclGroup());
+  for (Decl *ToD : ToDG) {
+    if (!ToD)
+      return nullptr;
+  }
+  SourceLocation ToStartLoc = Importer.Import(S->getStartLoc());
+  SourceLocation ToEndLoc = Importer.Import(S->getEndLoc());
+  return new (Importer.getToContext()) DeclStmt(ToDG, ToStartLoc, ToEndLoc);
+}
+
+Stmt *ASTNodeImporter::VisitNullStmt(NullStmt *S) {
+  SourceLocation ToSemiLoc = Importer.Import(S->getSemiLoc());
+  return new (Importer.getToContext()) NullStmt(ToSemiLoc,
+                                                S->hasLeadingEmptyMacro());
+}
+
+Stmt *ASTNodeImporter::VisitCompoundStmt(CompoundStmt *S) {
+  SmallVector<Stmt *, 4> ToStmts(S->size());
+  auto &_Importer = this->Importer;
+  std::transform(S->body_begin(), S->body_end(), ToStmts.begin(),
+    [&_Importer](Stmt *CS) -> Stmt * {
+      return _Importer.Import(CS);
+    });
+  for (Stmt *ToS : ToStmts) {
+    if (!ToS)
+      return nullptr;
+  }
+  SourceLocation ToLBraceLoc = Importer.Import(S->getLBracLoc());
+  SourceLocation ToRBraceLoc = Importer.Import(S->getRBracLoc());
+  return new (Importer.getToContext()) CompoundStmt(Importer.getToContext(),
+                                                    ToStmts,
+                                                    ToLBraceLoc, ToRBraceLoc);
+}
+
+Stmt *ASTNodeImporter::VisitCaseStmt(CaseStmt *S) {
+  Expr *ToLHS = Importer.Import(S->getLHS());
+  if (!ToLHS)
+    return nullptr;
+  Expr *ToRHS = Importer.Import(S->getRHS());
+  if (!ToRHS && S->getRHS())
+    return nullptr;
+  SourceLocation ToCaseLoc = Importer.Import(S->getCaseLoc());
+  SourceLocation ToEllipsisLoc = Importer.Import(S->getEllipsisLoc());
+  SourceLocation ToColonLoc = Importer.Import(S->getColonLoc());
+  return new (Importer.getToContext()) CaseStmt(ToLHS, ToRHS,
+                                                ToCaseLoc, ToEllipsisLoc,
+                                                ToColonLoc);
+}
+
+Stmt *ASTNodeImporter::VisitDefaultStmt(DefaultStmt *S) {
+  SourceLocation ToDefaultLoc = Importer.Import(S->getDefaultLoc());
+  SourceLocation ToColonLoc = Importer.Import(S->getColonLoc());
+  Stmt *ToSubStmt = Importer.Import(S->getSubStmt());
+  if (!ToSubStmt && S->getSubStmt())
+    return nullptr;
+  return new (Importer.getToContext()) DefaultStmt(ToDefaultLoc, ToColonLoc,
+                                                   ToSubStmt);
+}
+
+Stmt *ASTNodeImporter::VisitLabelStmt(LabelStmt *S) {
+  SourceLocation ToIdentLoc = Importer.Import(S->getIdentLoc());
+  LabelDecl *ToLabelDecl =
+    cast_or_null<LabelDecl>(Importer.Import(S->getDecl()));
+  if (!ToLabelDecl && S->getDecl())
+    return nullptr;
+  Stmt *ToSubStmt = Importer.Import(S->getSubStmt());
+  if (!ToSubStmt && S->getSubStmt())
+    return nullptr;
+  return new (Importer.getToContext()) LabelStmt(ToIdentLoc, ToLabelDecl,
+                                                 ToSubStmt);
+}
+
+Stmt *ASTNodeImporter::VisitAttributedStmt(AttributedStmt *S) {
+  SourceLocation ToAttrLoc = Importer.Import(S->getAttrLoc());
+  ArrayRef<const Attr*> FromAttrs(S->getAttrs());
+  SmallVector<const Attr *, 1> ToAttrs(FromAttrs.size());
+  ASTContext &_ToContext = Importer.getToContext();
+  std::transform(FromAttrs.begin(), FromAttrs.end(), ToAttrs.begin(),
+    [&_ToContext](const Attr *A) -> const Attr * {
+      return A->clone(_ToContext);
+    });
+  for (const Attr *ToA : ToAttrs) {
+    if (!ToA)
+      return nullptr;
+  }
+  Stmt *ToSubStmt = Importer.Import(S->getSubStmt());
+  if (!ToSubStmt && S->getSubStmt())
+    return nullptr;
+  return AttributedStmt::Create(Importer.getToContext(), ToAttrLoc,
+                                ToAttrs, ToSubStmt);
+}
+
+Stmt *ASTNodeImporter::VisitIfStmt(IfStmt *S) {
+  SourceLocation ToIfLoc = Importer.Import(S->getIfLoc());
+  VarDecl *ToConditionVariable = nullptr;
+  if (VarDecl *FromConditionVariable = S->getConditionVariable()) {
+    ToConditionVariable =
+      dyn_cast_or_null<VarDecl>(Importer.Import(FromConditionVariable));
+    if (!ToConditionVariable)
+      return nullptr;
+  }
+  Expr *ToCondition = Importer.Import(S->getCond());
+  if (!ToCondition && S->getCond())
+    return nullptr;
+  Stmt *ToThenStmt = Importer.Import(S->getThen());
+  if (!ToThenStmt && S->getThen())
+    return nullptr;
+  SourceLocation ToElseLoc = Importer.Import(S->getElseLoc());
+  Stmt *ToElseStmt = Importer.Import(S->getElse());
+  if (!ToElseStmt && S->getElse())
+    return nullptr;
+  return new (Importer.getToContext()) IfStmt(Importer.getToContext(),
+                                              ToIfLoc, ToConditionVariable,
+                                              ToCondition, ToThenStmt,
+                                              ToElseLoc, ToElseStmt);
+}
+
+Stmt *ASTNodeImporter::VisitSwitchStmt(SwitchStmt *S) {
+  VarDecl *ToConditionVariable = nullptr;
+  if (VarDecl *FromConditionVariable = S->getConditionVariable()) {
+    ToConditionVariable =
+      dyn_cast_or_null<VarDecl>(Importer.Import(FromConditionVariable));
+    if (!ToConditionVariable)
+      return nullptr;
+  }
+  Expr *ToCondition = Importer.Import(S->getCond());
+  if (!ToCondition && S->getCond())
+    return nullptr;
+  SwitchStmt *ToStmt = new (Importer.getToContext()) SwitchStmt(
+                         Importer.getToContext(), ToConditionVariable,
+                         ToCondition);
+  Stmt *ToBody = Importer.Import(S->getBody());
+  if (!ToBody && S->getBody())
+    return nullptr;
+  ToStmt->setBody(ToBody);
+  ToStmt->setSwitchLoc(Importer.Import(S->getSwitchLoc()));
+  // Now we have to re-chain the cases.
+  SwitchCase *LastChainedSwitchCase = nullptr;
+  for (SwitchCase *SC = S->getSwitchCaseList(); SC != nullptr;
+       SC = SC->getNextSwitchCase()) {
+    SwitchCase *ToSC = dyn_cast_or_null<SwitchCase>(Importer.Import(SC));
+    if (!ToSC)
+      return nullptr;
+    if (LastChainedSwitchCase)
+      LastChainedSwitchCase->setNextSwitchCase(ToSC);
+    else
+      ToStmt->setSwitchCaseList(ToSC);
+    LastChainedSwitchCase = ToSC;
+  }
+  return ToStmt;
+}
+
+Stmt *ASTNodeImporter::VisitWhileStmt(WhileStmt *S) {
+  VarDecl *ToConditionVariable = nullptr;
+  if (VarDecl *FromConditionVariable = S->getConditionVariable()) {
+    ToConditionVariable =
+      dyn_cast_or_null<VarDecl>(Importer.Import(FromConditionVariable));
+    if (!ToConditionVariable)
+      return nullptr;
+  }
+  Expr *ToCondition = Importer.Import(S->getCond());
+  if (!ToCondition && S->getCond())
+    return nullptr;
+  Stmt *ToBody = Importer.Import(S->getBody());
+  if (!ToBody && S->getBody())
+    return nullptr;
+  SourceLocation ToWhileLoc = Importer.Import(S->getWhileLoc());
+  return new (Importer.getToContext()) WhileStmt(Importer.getToContext(),
+                                                 ToConditionVariable,
+                                                 ToCondition, ToBody,
+                                                 ToWhileLoc);
+}
+
+Stmt *ASTNodeImporter::VisitDoStmt(DoStmt *S) {
+  Stmt *ToBody = Importer.Import(S->getBody());
+  if (!ToBody && S->getBody())
+    return nullptr;
+  Expr *ToCondition = Importer.Import(S->getCond());
+  if (!ToCondition && S->getCond())
+    return nullptr;
+  SourceLocation ToDoLoc = Importer.Import(S->getDoLoc());
+  SourceLocation ToWhileLoc = Importer.Import(S->getWhileLoc());
+  SourceLocation ToRParenLoc = Importer.Import(S->getRParenLoc());
+  return new (Importer.getToContext()) DoStmt(ToBody, ToCondition,
+                                              ToDoLoc, ToWhileLoc,
+                                              ToRParenLoc);
+}
+
+Stmt *ASTNodeImporter::VisitForStmt(ForStmt *S) {
+  Stmt *ToInit = Importer.Import(S->getInit());
+  if (!ToInit && S->getInit())
+    return nullptr;
+  Expr *ToCondition = Importer.Import(S->getCond());
+  if (!ToCondition && S->getCond())
+    return nullptr;
+  VarDecl *ToConditionVariable = nullptr;
+  if (VarDecl *FromConditionVariable = S->getConditionVariable()) {
+    ToConditionVariable =
+      dyn_cast_or_null<VarDecl>(Importer.Import(FromConditionVariable));
+    if (!ToConditionVariable)
+      return nullptr;
+  }
+  Expr *ToInc = Importer.Import(S->getInc());
+  if (!ToInc && S->getInc())
+    return nullptr;
+  Stmt *ToBody = Importer.Import(S->getBody());
+  if (!ToBody && S->getBody())
+    return nullptr;
+  SourceLocation ToForLoc = Importer.Import(S->getForLoc());
+  SourceLocation ToLParenLoc = Importer.Import(S->getLParenLoc());
+  SourceLocation ToRParenLoc = Importer.Import(S->getRParenLoc());
+  return new (Importer.getToContext()) ForStmt(Importer.getToContext(),
+                                               ToInit, ToCondition,
+                                               ToConditionVariable,
+                                               ToInc, ToBody,
+                                               ToForLoc, ToLParenLoc,
+                                               ToRParenLoc);
+}
+
+Stmt *ASTNodeImporter::VisitGotoStmt(GotoStmt *S) {
+  LabelDecl *ToLabel = nullptr;
+  if (LabelDecl *FromLabel = S->getLabel()) {
+    ToLabel = dyn_cast_or_null<LabelDecl>(Importer.Import(FromLabel));
+    if (!ToLabel)
+      return nullptr;
+  }
+  SourceLocation ToGotoLoc = Importer.Import(S->getGotoLoc());
+  SourceLocation ToLabelLoc = Importer.Import(S->getLabelLoc());
+  return new (Importer.getToContext()) GotoStmt(ToLabel,
+                                                ToGotoLoc, ToLabelLoc);
+}
+
+Stmt *ASTNodeImporter::VisitIndirectGotoStmt(IndirectGotoStmt *S) {
+  SourceLocation ToGotoLoc = Importer.Import(S->getGotoLoc());
+  SourceLocation ToStarLoc = Importer.Import(S->getStarLoc());
+  Expr *ToTarget = Importer.Import(S->getTarget());
+  if (!ToTarget && S->getTarget())
+    return nullptr;
+  return new (Importer.getToContext()) IndirectGotoStmt(ToGotoLoc, ToStarLoc,
+                                                        ToTarget);
+}
+
+Stmt *ASTNodeImporter::VisitContinueStmt(ContinueStmt *S) {
+  SourceLocation ToContinueLoc = Importer.Import(S->getContinueLoc());
+  return new (Importer.getToContext()) ContinueStmt(ToContinueLoc);
+}
+
+Stmt *ASTNodeImporter::VisitBreakStmt(BreakStmt *S) {
+  SourceLocation ToBreakLoc = Importer.Import(S->getBreakLoc());
+  return new (Importer.getToContext()) BreakStmt(ToBreakLoc);
+}
+
+Stmt *ASTNodeImporter::VisitReturnStmt(ReturnStmt *S) {
+  SourceLocation ToRetLoc = Importer.Import(S->getReturnLoc());
+  Expr *ToRetExpr = Importer.Import(S->getRetValue());
+  if (!ToRetExpr && S->getRetValue())
+    return nullptr;
+  VarDecl *NRVOCandidate = const_cast<VarDecl*>(S->getNRVOCandidate());
+  VarDecl *ToNRVOCandidate = cast_or_null<VarDecl>(Importer.Import(NRVOCandidate));
+  if (!ToNRVOCandidate && NRVOCandidate)
+    return nullptr;
+  return new (Importer.getToContext()) ReturnStmt(ToRetLoc, ToRetExpr,
+                                                  ToNRVOCandidate);
+}
+
+Stmt *ASTNodeImporter::VisitCXXCatchStmt(CXXCatchStmt *S) {
+  SourceLocation ToCatchLoc = Importer.Import(S->getCatchLoc());
+  VarDecl *ToExceptionDecl = nullptr;
+  if (VarDecl *FromExceptionDecl = S->getExceptionDecl()) {
+    ToExceptionDecl =
+      dyn_cast_or_null<VarDecl>(Importer.Import(FromExceptionDecl));
+    if (!ToExceptionDecl)
+      return nullptr;
+  }
+  Stmt *ToHandlerBlock = Importer.Import(S->getHandlerBlock());
+  if (!ToHandlerBlock && S->getHandlerBlock())
+    return nullptr;
+  return new (Importer.getToContext()) CXXCatchStmt(ToCatchLoc,
+                                                    ToExceptionDecl,
+                                                    ToHandlerBlock);
+}
+
+Stmt *ASTNodeImporter::VisitCXXTryStmt(CXXTryStmt *S) {
+  SourceLocation ToTryLoc = Importer.Import(S->getTryLoc());
+  Stmt *ToTryBlock = Importer.Import(S->getTryBlock());
+  if (!ToTryBlock && S->getTryBlock())
+    return nullptr;
+  SmallVector<Stmt *, 1> ToHandlers(S->getNumHandlers());
+  for (unsigned HI = 0, HE = S->getNumHandlers(); HI != HE; ++HI) {
+    CXXCatchStmt *FromHandler = S->getHandler(HI);
+    if (Stmt *ToHandler = Importer.Import(FromHandler))
+      ToHandlers[HI] = ToHandler;
+    else
+      return nullptr;
+  }
+  return CXXTryStmt::Create(Importer.getToContext(), ToTryLoc, ToTryBlock,
+                            ToHandlers);
+}
+
+Stmt *ASTNodeImporter::VisitCXXForRangeStmt(CXXForRangeStmt *S) {
+  DeclStmt *ToRange =
+    dyn_cast_or_null<DeclStmt>(Importer.Import(S->getRangeStmt()));
+  if (!ToRange && S->getRangeStmt())
+    return nullptr;
+  DeclStmt *ToBeginEnd =
+    dyn_cast_or_null<DeclStmt>(Importer.Import(S->getBeginEndStmt()));
+  if (!ToBeginEnd && S->getBeginEndStmt())
+    return nullptr;
+  Expr *ToCond = Importer.Import(S->getCond());
+  if (!ToCond && S->getCond())
+    return nullptr;
+  Expr *ToInc = Importer.Import(S->getInc());
+  if (!ToInc && S->getInc())
+    return nullptr;
+  DeclStmt *ToLoopVar =
+    dyn_cast_or_null<DeclStmt>(Importer.Import(S->getLoopVarStmt()));
+  if (!ToLoopVar && S->getLoopVarStmt())
+    return nullptr;
+  Stmt *ToBody = Importer.Import(S->getBody());
+  if (!ToBody && S->getBody())
+    return nullptr;
+  SourceLocation ToForLoc = Importer.Import(S->getForLoc());
+  SourceLocation ToColonLoc = Importer.Import(S->getColonLoc());
+  SourceLocation ToRParenLoc = Importer.Import(S->getRParenLoc());
+  return new (Importer.getToContext()) CXXForRangeStmt(ToRange, ToBeginEnd,
+                                                       ToCond, ToInc,
+                                                       ToLoopVar, ToBody,
+                                                       ToForLoc, ToColonLoc,
+                                                       ToRParenLoc);
+}
+
+Stmt *ASTNodeImporter::VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
+  Stmt *ToElem = Importer.Import(S->getElement());
+  if (!ToElem && S->getElement())
+    return nullptr;
+  Expr *ToCollect = Importer.Import(S->getCollection());
+  if (!ToCollect && S->getCollection())
+    return nullptr;
+  Stmt *ToBody = Importer.Import(S->getBody());
+  if (!ToBody && S->getBody())
+    return nullptr;
+  SourceLocation ToForLoc = Importer.Import(S->getForLoc());
+  SourceLocation ToRParenLoc = Importer.Import(S->getRParenLoc());
+  return new (Importer.getToContext()) ObjCForCollectionStmt(ToElem,
+                                                             ToCollect,
+                                                             ToBody, ToForLoc,
+                                                             ToRParenLoc);
+}
+
+Stmt *ASTNodeImporter::VisitObjCAtCatchStmt(ObjCAtCatchStmt *S) {
+  SourceLocation ToAtCatchLoc = Importer.Import(S->getAtCatchLoc());
+  SourceLocation ToRParenLoc = Importer.Import(S->getRParenLoc());
+  VarDecl *ToExceptionDecl = nullptr;
+  if (VarDecl *FromExceptionDecl = S->getCatchParamDecl()) {
+    ToExceptionDecl =
+      dyn_cast_or_null<VarDecl>(Importer.Import(FromExceptionDecl));
+    if (!ToExceptionDecl)
+      return nullptr;
+  }
+  Stmt *ToBody = Importer.Import(S->getCatchBody());
+  if (!ToBody && S->getCatchBody())
+    return nullptr;
+  return new (Importer.getToContext()) ObjCAtCatchStmt(ToAtCatchLoc,
+                                                       ToRParenLoc,
+                                                       ToExceptionDecl,
+                                                       ToBody);
+}
+
+Stmt *ASTNodeImporter::VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *S) {
+  SourceLocation ToAtFinallyLoc = Importer.Import(S->getAtFinallyLoc());
+  Stmt *ToAtFinallyStmt = Importer.Import(S->getFinallyBody());
+  if (!ToAtFinallyStmt && S->getFinallyBody())
+    return nullptr;
+  return new (Importer.getToContext()) ObjCAtFinallyStmt(ToAtFinallyLoc,
+                                                         ToAtFinallyStmt);
+}
+
+Stmt *ASTNodeImporter::VisitObjCAtTryStmt(ObjCAtTryStmt *S) {
+  SourceLocation ToAtTryLoc = Importer.Import(S->getAtTryLoc());
+  Stmt *ToAtTryStmt = Importer.Import(S->getTryBody());
+  if (!ToAtTryStmt && S->getTryBody())
+    return nullptr;
+  SmallVector<Stmt *, 1> ToCatchStmts(S->getNumCatchStmts());
+  for (unsigned CI = 0, CE = S->getNumCatchStmts(); CI != CE; ++CI) {
+    ObjCAtCatchStmt *FromCatchStmt = S->getCatchStmt(CI);
+    if (Stmt *ToCatchStmt = Importer.Import(FromCatchStmt))
+      ToCatchStmts[CI] = ToCatchStmt;
+    else
+      return nullptr;
+  }
+  Stmt *ToAtFinallyStmt = Importer.Import(S->getFinallyStmt());
+  if (!ToAtFinallyStmt && S->getFinallyStmt())
+    return nullptr;
+  return ObjCAtTryStmt::Create(Importer.getToContext(),
+                               ToAtTryLoc, ToAtTryStmt,
+                               ToCatchStmts.begin(), ToCatchStmts.size(),
+                               ToAtFinallyStmt);
+}
+
+Stmt *ASTNodeImporter::VisitObjCAtSynchronizedStmt
+  (ObjCAtSynchronizedStmt *S) {
+  SourceLocation ToAtSynchronizedLoc =
+    Importer.Import(S->getAtSynchronizedLoc());
+  Expr *ToSynchExpr = Importer.Import(S->getSynchExpr());
+  if (!ToSynchExpr && S->getSynchExpr())
+    return nullptr;
+  Stmt *ToSynchBody = Importer.Import(S->getSynchBody());
+  if (!ToSynchBody && S->getSynchBody())
+    return nullptr;
+  return new (Importer.getToContext()) ObjCAtSynchronizedStmt(
+    ToAtSynchronizedLoc, ToSynchExpr, ToSynchBody);
+}
+
+Stmt *ASTNodeImporter::VisitObjCAtThrowStmt(ObjCAtThrowStmt *S) {
+  SourceLocation ToAtThrowLoc = Importer.Import(S->getThrowLoc());
+  Expr *ToThrow = Importer.Import(S->getThrowExpr());
+  if (!ToThrow && S->getThrowExpr())
+    return nullptr;
+  return new (Importer.getToContext()) ObjCAtThrowStmt(ToAtThrowLoc, ToThrow);
+}
+
+Stmt *ASTNodeImporter::VisitObjCAutoreleasePoolStmt
+  (ObjCAutoreleasePoolStmt *S) {
+  SourceLocation ToAtLoc = Importer.Import(S->getAtLoc());
+  Stmt *ToSubStmt = Importer.Import(S->getSubStmt());
+  if (!ToSubStmt && S->getSubStmt())
+    return nullptr;
+  return new (Importer.getToContext()) ObjCAutoreleasePoolStmt(ToAtLoc,
+                                                               ToSubStmt);
 }
 
 //----------------------------------------------------------------------------
@@ -4585,6 +5163,107 @@ Expr *ASTNodeImporter::VisitCStyleCastExpr(CStyleCastExpr *E) {
                                 Importer.Import(E->getRParenLoc()));
 }
 
+Expr *ASTNodeImporter::VisitCXXConstructExpr(CXXConstructExpr *E) {
+  QualType T = Importer.Import(E->getType());
+  if (T.isNull())
+    return nullptr;
+
+  CXXConstructorDecl *ToCCD =
+    dyn_cast<CXXConstructorDecl>(Importer.Import(E->getConstructor()));
+  if (!ToCCD && E->getConstructor())
+    return nullptr;
+
+  size_t NumArgs = E->getNumArgs();
+  SmallVector<Expr *, 1> ToArgs(NumArgs);
+  ASTImporter &_Importer = Importer;
+  std::transform(E->arg_begin(), E->arg_end(), ToArgs.begin(),
+    [&_Importer](Expr *AE) -> Expr * {
+      return _Importer.Import(AE);
+    });
+  for (Expr *ToA : ToArgs) {
+    if (!ToA)
+      return nullptr;
+  }
+
+  return CXXConstructExpr::Create(Importer.getToContext(), T,
+                                  Importer.Import(E->getLocation()),
+                                  ToCCD, E->isElidable(),
+                                  ToArgs, E->hadMultipleCandidates(),
+                                  E->isListInitialization(),
+                                  E->isStdInitListInitialization(),
+                                  E->requiresZeroInitialization(),
+                                  E->getConstructionKind(),
+                                  Importer.Import(E->getParenOrBraceRange()));
+}
+
+Expr *ASTNodeImporter::VisitMemberExpr(MemberExpr *E) {
+  QualType T = Importer.Import(E->getType());
+  if (T.isNull())
+    return nullptr;
+
+  Expr *ToBase = Importer.Import(E->getBase());
+  if (!ToBase && E->getBase())
+    return nullptr;
+
+  ValueDecl *ToMember = dyn_cast<ValueDecl>(Importer.Import(E->getMemberDecl()));
+  if (!ToMember && E->getMemberDecl())
+    return nullptr;
+
+  DeclAccessPair ToFoundDecl = DeclAccessPair::make(
+    dyn_cast<NamedDecl>(Importer.Import(E->getFoundDecl().getDecl())),
+    E->getFoundDecl().getAccess());
+
+  DeclarationNameInfo ToMemberNameInfo(
+    Importer.Import(E->getMemberNameInfo().getName()),
+    Importer.Import(E->getMemberNameInfo().getLoc()));
+
+  if (E->hasExplicitTemplateArgs()) {
+    return nullptr; // FIXME: handle template arguments
+  }
+
+  return MemberExpr::Create(Importer.getToContext(), ToBase,
+                            E->isArrow(),
+                            Importer.Import(E->getOperatorLoc()),
+                            Importer.Import(E->getQualifierLoc()),
+                            Importer.Import(E->getTemplateKeywordLoc()),
+                            ToMember, ToFoundDecl, ToMemberNameInfo,
+                            nullptr, T, E->getValueKind(),
+                            E->getObjectKind());
+}
+
+Expr *ASTNodeImporter::VisitCallExpr(CallExpr *E) {
+  QualType T = Importer.Import(E->getType());
+  if (T.isNull())
+    return nullptr;
+
+  Expr *ToCallee = Importer.Import(E->getCallee());
+  if (!ToCallee && E->getCallee())
+    return nullptr;
+
+  unsigned NumArgs = E->getNumArgs();
+
+  llvm::SmallVector<Expr *, 2> ToArgs(NumArgs);
+
+  for (unsigned ai = 0, ae = NumArgs; ai != ae; ++ai) {
+    Expr *FromArg = E->getArg(ai);
+    Expr *ToArg = Importer.Import(FromArg);
+    if (!ToArg)
+      return nullptr;
+    ToArgs[ai] = ToArg;
+  }
+
+  Expr **ToArgs_Copied = new (Importer.getToContext()) 
+    Expr*[NumArgs];
+
+  for (unsigned ai = 0, ae = NumArgs; ai != ae; ++ai)
+    ToArgs_Copied[ai] = ToArgs[ai];
+
+  return new (Importer.getToContext())
+    CallExpr(Importer.getToContext(), ToCallee, 
+             ArrayRef<Expr*>(ToArgs_Copied, NumArgs), T, E->getValueKind(),
+             Importer.Import(E->getRParenLoc()));
+}
+
 ASTImporter::ASTImporter(ASTContext &ToContext, FileManager &ToFileManager,
                          ASTContext &FromContext, FileManager &FromFileManager,
                          bool MinimalImport)
@@ -4636,6 +5315,17 @@ TypeSourceInfo *ASTImporter::Import(TypeSourceInfo *FromTSI) {
                         FromTSI->getTypeLoc().getLocStart());
 }
 
+Decl *ASTImporter::GetAlreadyImportedOrNull(Decl *FromD) {
+  llvm::DenseMap<Decl *, Decl *>::iterator Pos = ImportedDecls.find(FromD);
+  if (Pos != ImportedDecls.end()) {
+    Decl *ToD = Pos->second;
+    ASTNodeImporter(*this).ImportDefinitionIfNeeded(FromD, ToD);
+    return ToD;
+  } else {
+    return nullptr;
+  }
+}
+
 Decl *ASTImporter::Import(Decl *FromD) {
   if (!FromD)
     return nullptr;
@@ -4927,8 +5617,9 @@ SourceLocation ASTImporter::Import(SourceLocation FromLoc) {
   FileID ToFileID = Import(Decomposed.first);
   if (ToFileID.isInvalid())
     return SourceLocation();
-  return ToSM.getLocForStartOfFile(ToFileID)
-             .getLocWithOffset(Decomposed.second);
+  SourceLocation ret = ToSM.getLocForStartOfFile(ToFileID)
+                           .getLocWithOffset(Decomposed.second);
+  return ret;
 }
 
 SourceRange ASTImporter::Import(SourceRange FromRange) {
@@ -4952,7 +5643,7 @@ FileID ASTImporter::Import(FileID FromID) {
   // Map the FileID for to the "to" source manager.
   FileID ToID;
   const SrcMgr::ContentCache *Cache = FromSLoc.getFile().getContentCache();
-  if (Cache->OrigEntry) {
+  if (Cache->OrigEntry && Cache->OrigEntry->getDir()) {
     // FIXME: We probably want to use getVirtualFile(), so we don't hit the
     // disk again
     // FIXME: We definitely want to re-use the existing MemoryBuffer, rather
diff --git a/lib/AST/AttrImpl.cpp b/lib/AST/AttrImpl.cpp
index 0bf6bcd9092e..cb608700133c 100644
--- a/lib/AST/AttrImpl.cpp
+++ b/lib/AST/AttrImpl.cpp
@@ -7,7 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-//  This file contains out-of-line virtual methods for Attr classes.
+//  This file contains out-of-line methods for Attr classes.
 //
 //===----------------------------------------------------------------------===//
 
@@ -18,10 +18,4 @@
 #include "llvm/ADT/StringSwitch.h"
 using namespace clang;
 
-Attr::~Attr() { }
-
-void InheritableAttr::anchor() { }
-
-void InheritableParamAttr::anchor() { }
-
 #include "clang/AST/AttrImpl.inc"
diff --git a/lib/AST/CXXABI.h b/lib/AST/CXXABI.h
index 8e9e358525e8..dad226474fa7 100644
--- a/lib/AST/CXXABI.h
+++ b/lib/AST/CXXABI.h
@@ -20,6 +20,8 @@
 namespace clang {
 
 class ASTContext;
+class CXXConstructorDecl;
+class Expr;
 class MemberPointerType;
 class MangleNumberingContext;
 
@@ -41,6 +43,20 @@ public:
 
   /// Returns a new mangling number context for this C++ ABI.
   virtual MangleNumberingContext *createMangleNumberingContext() const = 0;
+
+  /// Adds a mapping from class to copy constructor for this C++ ABI.
+  virtual void addCopyConstructorForExceptionObject(CXXRecordDecl *,
+                                                    CXXConstructorDecl *) = 0;
+
+  /// Retrieves the mapping from class to copy constructor for this C++ ABI.
+  virtual const CXXConstructorDecl *
+  getCopyConstructorForExceptionObject(CXXRecordDecl *) = 0;
+
+  virtual void addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                               unsigned ParmIdx, Expr *DAE) = 0;
+
+  virtual Expr *getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                                unsigned ParmIdx) = 0;
 };
 
 /// Creates an instance of a C++ ABI class.
diff --git a/lib/AST/CXXInheritance.cpp b/lib/AST/CXXInheritance.cpp
index 6e80ee7c28a1..800c8f83b880 100644
--- a/lib/AST/CXXInheritance.cpp
+++ b/lib/AST/CXXInheritance.cpp
@@ -318,48 +318,36 @@ bool CXXRecordDecl::lookupInBases(BaseMatchesCallback *BaseMatches,
   //
   // FIXME: This is an O(N^2) algorithm, but DPG doesn't see an easy
   // way to make it any faster.
-  for (CXXBasePaths::paths_iterator P = Paths.begin(), PEnd = Paths.end();
-       P != PEnd; /* increment in loop */) {
-    bool Hidden = false;
-
-    for (CXXBasePath::iterator PE = P->begin(), PEEnd = P->end();
-         PE != PEEnd && !Hidden; ++PE) {
-      if (PE->Base->isVirtual()) {
-        CXXRecordDecl *VBase = nullptr;
-        if (const RecordType *Record = PE->Base->getType()->getAs<RecordType>())
-          VBase = cast<CXXRecordDecl>(Record->getDecl());
-        if (!VBase)
+  Paths.Paths.remove_if([&Paths](const CXXBasePath &Path) {
+    for (const CXXBasePathElement &PE : Path) {
+      if (!PE.Base->isVirtual())
+        continue;
+
+      CXXRecordDecl *VBase = nullptr;
+      if (const RecordType *Record = PE.Base->getType()->getAs<RecordType>())
+        VBase = cast<CXXRecordDecl>(Record->getDecl());
+      if (!VBase)
+        break;
+
+      // The declaration(s) we found along this path were found in a
+      // subobject of a virtual base. Check whether this virtual
+      // base is a subobject of any other path; if so, then the
+      // declaration in this path are hidden by that patch.
+      for (const CXXBasePath &HidingP : Paths) {
+        CXXRecordDecl *HidingClass = nullptr;
+        if (const RecordType *Record =
+                HidingP.back().Base->getType()->getAs<RecordType>())
+          HidingClass = cast<CXXRecordDecl>(Record->getDecl());
+        if (!HidingClass)
           break;
 
-        // The declaration(s) we found along this path were found in a
-        // subobject of a virtual base. Check whether this virtual
-        // base is a subobject of any other path; if so, then the
-        // declaration in this path are hidden by that patch.
-        for (CXXBasePaths::paths_iterator HidingP = Paths.begin(),
-                                       HidingPEnd = Paths.end();
-             HidingP != HidingPEnd;
-             ++HidingP) {
-          CXXRecordDecl *HidingClass = nullptr;
-          if (const RecordType *Record
-                       = HidingP->back().Base->getType()->getAs<RecordType>())
-            HidingClass = cast<CXXRecordDecl>(Record->getDecl());
-          if (!HidingClass)
-            break;
-
-          if (HidingClass->isVirtuallyDerivedFrom(VBase)) {
-            Hidden = true;
-            break;
-          }
-        }
+        if (HidingClass->isVirtuallyDerivedFrom(VBase))
+          return true;
       }
     }
+    return false;
+  });
 
-    if (Hidden)
-      P = Paths.Paths.erase(P);
-    else
-      ++P;
-  }
-  
   return true;
 }
 
@@ -569,18 +557,14 @@ void FinalOverriderCollector::Collect(const CXXRecordDecl *RD,
     // overrider. To do so, we dig down to the original virtual
     // functions using data recursion and update all of the methods it
     // overrides.
-    typedef std::pair<CXXMethodDecl::method_iterator, 
-                      CXXMethodDecl::method_iterator> OverriddenMethods;
+    typedef llvm::iterator_range<CXXMethodDecl::method_iterator>
+        OverriddenMethods;
     SmallVector<OverriddenMethods, 4> Stack;
-    Stack.push_back(std::make_pair(CanonM->begin_overridden_methods(),
-                                   CanonM->end_overridden_methods()));
+    Stack.push_back(llvm::make_range(CanonM->begin_overridden_methods(),
+                                     CanonM->end_overridden_methods()));
     while (!Stack.empty()) {
-      OverriddenMethods OverMethods = Stack.back();
-      Stack.pop_back();
-
-      for (; OverMethods.first != OverMethods.second; ++OverMethods.first) {
-        const CXXMethodDecl *CanonOM
-          = cast<CXXMethodDecl>((*OverMethods.first)->getCanonicalDecl());
+      for (const CXXMethodDecl *OM : Stack.pop_back_val()) {
+        const CXXMethodDecl *CanonOM = OM->getCanonicalDecl();
 
         // C++ [class.virtual]p2:
         //   A virtual member function C::vf of a class object S is
@@ -601,8 +585,8 @@ void FinalOverriderCollector::Collect(const CXXRecordDecl *RD,
 
         // Continue recursion to the methods that this virtual method
         // overrides.
-        Stack.push_back(std::make_pair(CanonOM->begin_overridden_methods(),
-                                       CanonOM->end_overridden_methods()));
+        Stack.push_back(llvm::make_range(CanonOM->begin_overridden_methods(),
+                                         CanonOM->end_overridden_methods()));
       }
     }
 
@@ -630,54 +614,32 @@ CXXRecordDecl::getFinalOverriders(CXXFinalOverriderMap &FinalOverriders) const {
   // Weed out any final overriders that come from virtual base class
   // subobjects that were hidden by other subobjects along any path.
   // This is the final-overrider variant of C++ [class.member.lookup]p10.
-  for (CXXFinalOverriderMap::iterator OM = FinalOverriders.begin(), 
-                           OMEnd = FinalOverriders.end();
-       OM != OMEnd;
-       ++OM) {
-    for (OverridingMethods::iterator SO = OM->second.begin(), 
-                                  SOEnd = OM->second.end();
-         SO != SOEnd; 
-         ++SO) {
-      SmallVectorImpl<UniqueVirtualMethod> &Overriding = SO->second;
+  for (auto &OM : FinalOverriders) {
+    for (auto &SO : OM.second) {
+      SmallVectorImpl<UniqueVirtualMethod> &Overriding = SO.second;
       if (Overriding.size() < 2)
         continue;
 
-      for (SmallVectorImpl<UniqueVirtualMethod>::iterator
-             Pos = Overriding.begin(), PosEnd = Overriding.end();
-           Pos != PosEnd;
-           /* increment in loop */) {
-        if (!Pos->InVirtualSubobject) {
-          ++Pos;
-          continue;
-        }
+      auto IsHidden = [&Overriding](const UniqueVirtualMethod &M) {
+        if (!M.InVirtualSubobject)
+          return false;
 
         // We have an overriding method in a virtual base class
         // subobject (or non-virtual base class subobject thereof);
         // determine whether there exists an other overriding method
         // in a base class subobject that hides the virtual base class
         // subobject.
-        bool Hidden = false;
-        for (SmallVectorImpl<UniqueVirtualMethod>::iterator
-               OP = Overriding.begin(), OPEnd = Overriding.end();
-             OP != OPEnd && !Hidden; 
-             ++OP) {
-          if (Pos == OP)
-            continue;
-
-          if (OP->Method->getParent()->isVirtuallyDerivedFrom(
-                         const_cast<CXXRecordDecl *>(Pos->InVirtualSubobject)))
-            Hidden = true;
-        }
-
-        if (Hidden) {
-          // The current overriding function is hidden by another
-          // overriding function; remove this one.
-          Pos = Overriding.erase(Pos);
-          PosEnd = Overriding.end();
-        } else {
-          ++Pos;
-        }
-      }
+        for (const UniqueVirtualMethod &OP : Overriding)
+          if (&M != &OP &&
+              OP.Method->getParent()->isVirtuallyDerivedFrom(
+                  M.InVirtualSubobject))
+            return true;
+        return false;
+      };
+
+      Overriding.erase(
+          std::remove_if(Overriding.begin(), Overriding.end(), IsHidden),
+          Overriding.end());
     }
   }
 }
diff --git a/lib/AST/CommentLexer.cpp b/lib/AST/CommentLexer.cpp
index 06a08bdad45f..98b7e367950c 100644
--- a/lib/AST/CommentLexer.cpp
+++ b/lib/AST/CommentLexer.cpp
@@ -514,6 +514,12 @@ void Lexer::lexVerbatimBlockBody(Token &T) {
   if (CommentState == LCS_InsideCComment)
     skipLineStartingDecorations();
 
+  if (BufferPtr == CommentEnd) {
+    formTokenWithChars(T, BufferPtr, tok::verbatim_block_line);
+    T.setVerbatimBlockText("");
+    return;
+  }
+
   lexVerbatimBlockFirstLine(T);
 }
 
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index dc08d23a24b5..8eff4c4427b3 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -44,6 +44,12 @@ bool Decl::isOutOfLine() const {
   return !getLexicalDeclContext()->Equals(getDeclContext());
 }
 
+TranslationUnitDecl::TranslationUnitDecl(ASTContext &ctx)
+    : Decl(TranslationUnit, nullptr, SourceLocation()),
+      DeclContext(TranslationUnit), Ctx(ctx), AnonymousNamespace(nullptr) {
+  Hidden = Ctx.getLangOpts().ModulesLocalVisibility;
+}
+
 //===----------------------------------------------------------------------===//
 // NamedDecl Implementation
 //===----------------------------------------------------------------------===//
@@ -894,13 +900,13 @@ static LinkageInfo getLVForClassMember(const NamedDecl *D,
   if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
     // If the type of the function uses a type with unique-external
     // linkage, it's not legally usable from outside this translation unit.
-    // But only look at the type-as-written. If this function has an auto-deduced
-    // return type, we can't compute the linkage of that type because it could
-    // require looking at the linkage of this function, and we don't need this
-    // for correctness because the type is not part of the function's
-    // signature.
-    // FIXME: This is a hack. We should be able to solve this circularity and the
-    // one in getLVForNamespaceScopeDecl for Functions some other way.
+    // But only look at the type-as-written. If this function has an
+    // auto-deduced return type, we can't compute the linkage of that type
+    // because it could require looking at the linkage of this function, and we
+    // don't need this for correctness because the type is not part of the
+    // function's signature.
+    // FIXME: This is a hack. We should be able to solve this circularity and
+    // the one in getLVForNamespaceScopeDecl for Functions some other way.
     {
       QualType TypeAsWritten = MD->getType();
       if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
@@ -1445,74 +1451,127 @@ void NamedDecl::getNameForDiagnostic(raw_ostream &OS,
     printName(OS);
 }
 
-bool NamedDecl::declarationReplaces(NamedDecl *OldD) const {
-  assert(getDeclName() == OldD->getDeclName() && "Declaration name mismatch");
+static bool isKindReplaceableBy(Decl::Kind OldK, Decl::Kind NewK) {
+  // For method declarations, we never replace.
+  if (ObjCMethodDecl::classofKind(NewK))
+    return false;
 
-  // UsingDirectiveDecl's are not really NamedDecl's, and all have same name.
-  // We want to keep it, unless it nominates same namespace.
-  if (getKind() == Decl::UsingDirective) {
-    return cast<UsingDirectiveDecl>(this)->getNominatedNamespace()
-             ->getOriginalNamespace() ==
-           cast<UsingDirectiveDecl>(OldD)->getNominatedNamespace()
-             ->getOriginalNamespace();
+  if (OldK == NewK)
+    return true;
+
+  // A compatibility alias for a class can be replaced by an interface.
+  if (ObjCCompatibleAliasDecl::classofKind(OldK) &&
+      ObjCInterfaceDecl::classofKind(NewK))
+    return true;
+
+  // A typedef-declaration, alias-declaration, or Objective-C class declaration
+  // can replace another declaration of the same type. Semantic analysis checks
+  // that we have matching types.
+  if ((TypedefNameDecl::classofKind(OldK) ||
+       ObjCInterfaceDecl::classofKind(OldK)) &&
+      (TypedefNameDecl::classofKind(NewK) ||
+       ObjCInterfaceDecl::classofKind(NewK)))
+    return true;
+
+  // Otherwise, a kind mismatch implies that the declaration is not replaced.
+  return false;
+}
+
+template<typename T> static bool isRedeclarableImpl(Redeclarable<T> *) {
+  return true;
+}
+static bool isRedeclarableImpl(...) { return false; }
+static bool isRedeclarable(Decl::Kind K) {
+  switch (K) {
+#define DECL(Type, Base) \
+  case Decl::Type: \
+    return isRedeclarableImpl((Type##Decl *)nullptr);
+#define ABSTRACT_DECL(DECL)
+#include "clang/AST/DeclNodes.inc"
   }
+  llvm_unreachable("unknown decl kind");
+}
 
-  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(this))
-    // For function declarations, we keep track of redeclarations.
-    return FD->getPreviousDecl() == OldD;
+bool NamedDecl::declarationReplaces(NamedDecl *OldD, bool IsKnownNewer) const {
+  assert(getDeclName() == OldD->getDeclName() && "Declaration name mismatch");
 
-  // For function templates, the underlying function declarations are linked.
-  if (const FunctionTemplateDecl *FunctionTemplate
-        = dyn_cast<FunctionTemplateDecl>(this))
-    if (const FunctionTemplateDecl *OldFunctionTemplate
-          = dyn_cast<FunctionTemplateDecl>(OldD))
-      return FunctionTemplate->getTemplatedDecl()
-               ->declarationReplaces(OldFunctionTemplate->getTemplatedDecl());
-
-  // For method declarations, we keep track of redeclarations.
-  if (isa<ObjCMethodDecl>(this))
+  // Never replace one imported declaration with another; we need both results
+  // when re-exporting.
+  if (OldD->isFromASTFile() && isFromASTFile())
     return false;
 
-  // FIXME: Is this correct if one of the decls comes from an inline namespace?
-  if (isa<ObjCInterfaceDecl>(this) && isa<ObjCCompatibleAliasDecl>(OldD))
-    return true;
+  if (!isKindReplaceableBy(OldD->getKind(), getKind()))
+    return false;
 
-  if (isa<UsingShadowDecl>(this) && isa<UsingShadowDecl>(OldD))
-    return cast<UsingShadowDecl>(this)->getTargetDecl() ==
-           cast<UsingShadowDecl>(OldD)->getTargetDecl();
+  // Inline namespaces can give us two declarations with the same
+  // name and kind in the same scope but different contexts; we should
+  // keep both declarations in this case.
+  if (!this->getDeclContext()->getRedeclContext()->Equals(
+          OldD->getDeclContext()->getRedeclContext()))
+    return false;
 
-  if (isa<UsingDecl>(this) && isa<UsingDecl>(OldD)) {
+  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(this))
+    // For function declarations, we keep track of redeclarations.
+    // FIXME: This returns false for functions that should in fact be replaced.
+    // Instead, perform some kind of type check?
+    if (FD->getPreviousDecl() != OldD)
+      return false;
+
+  // For function templates, the underlying function declarations are linked.
+  if (const FunctionTemplateDecl *FunctionTemplate =
+          dyn_cast<FunctionTemplateDecl>(this))
+    return FunctionTemplate->getTemplatedDecl()->declarationReplaces(
+        cast<FunctionTemplateDecl>(OldD)->getTemplatedDecl());
+
+  // Using shadow declarations can be overloaded on their target declarations
+  // if they introduce functions.
+  // FIXME: If our target replaces the old target, can we replace the old
+  //        shadow declaration?
+  if (auto *USD = dyn_cast<UsingShadowDecl>(this))
+    if (USD->getTargetDecl() != cast<UsingShadowDecl>(OldD)->getTargetDecl())
+      return false;
+
+  // Using declarations can be overloaded if they introduce functions.
+  if (auto *UD = dyn_cast<UsingDecl>(this)) {
     ASTContext &Context = getASTContext();
-    return Context.getCanonicalNestedNameSpecifier(
-                                     cast<UsingDecl>(this)->getQualifier()) ==
+    return Context.getCanonicalNestedNameSpecifier(UD->getQualifier()) ==
            Context.getCanonicalNestedNameSpecifier(
-                                        cast<UsingDecl>(OldD)->getQualifier());
+               cast<UsingDecl>(OldD)->getQualifier());
   }
-
-  if (isa<UnresolvedUsingValueDecl>(this) &&
-      isa<UnresolvedUsingValueDecl>(OldD)) {
+  if (auto *UUVD = dyn_cast<UnresolvedUsingValueDecl>(this)) {
     ASTContext &Context = getASTContext();
-    return Context.getCanonicalNestedNameSpecifier(
-                      cast<UnresolvedUsingValueDecl>(this)->getQualifier()) ==
+    return Context.getCanonicalNestedNameSpecifier(UUVD->getQualifier()) ==
            Context.getCanonicalNestedNameSpecifier(
                         cast<UnresolvedUsingValueDecl>(OldD)->getQualifier());
   }
 
-  // A typedef of an Objective-C class type can replace an Objective-C class
-  // declaration or definition, and vice versa.
-  // FIXME: Is this correct if one of the decls comes from an inline namespace?
-  if ((isa<TypedefNameDecl>(this) && isa<ObjCInterfaceDecl>(OldD)) ||
-      (isa<ObjCInterfaceDecl>(this) && isa<TypedefNameDecl>(OldD)))
-    return true;
+  // UsingDirectiveDecl's are not really NamedDecl's, and all have same name.
+  // We want to keep it, unless it nominates same namespace.
+  if (auto *UD = dyn_cast<UsingDirectiveDecl>(this))
+    return UD->getNominatedNamespace()->getOriginalNamespace() ==
+           cast<UsingDirectiveDecl>(OldD)->getNominatedNamespace()
+               ->getOriginalNamespace();
+
+  if (!IsKnownNewer && isRedeclarable(getKind())) {
+    // Check whether this is actually newer than OldD. We want to keep the
+    // newer declaration. This loop will usually only iterate once, because
+    // OldD is usually the previous declaration.
+    for (auto D : redecls()) {
+      if (D == OldD)
+        break;
 
-  // For non-function declarations, if the declarations are of the
-  // same kind and have the same parent then this must be a redeclaration,
-  // or semantic analysis would not have given us the new declaration.
-  // Note that inline namespaces can give us two declarations with the same
-  // name and kind in the same scope but different contexts.
-  return this->getKind() == OldD->getKind() &&
-         this->getDeclContext()->getRedeclContext()->Equals(
-             OldD->getDeclContext()->getRedeclContext());
+      // If we reach the canonical declaration, then OldD is not actually older
+      // than this one.
+      //
+      // FIXME: In this case, we should not add this decl to the lookup table.
+      if (D->isCanonicalDecl())
+        return false;
+    }
+  }
+
+  // It's a newer declaration of the same kind of declaration in the same scope,
+  // and not an overload: we want this decl instead of the existing one.
+  return true;
 }
 
 bool NamedDecl::hasLinkage() const {
@@ -1684,8 +1743,7 @@ QualifierInfo::setTemplateParameterListsInfo(ASTContext &Context,
   if (NumTPLists > 0) {
     TemplParamLists = new (Context) TemplateParameterList*[NumTPLists];
     NumTemplParamLists = NumTPLists;
-    for (unsigned i = NumTPLists; i-- > 0; )
-      TemplParamLists[i] = TPLists[i];
+    std::copy(TPLists, TPLists + NumTPLists, TemplParamLists);
   }
 }
 
@@ -1717,6 +1775,8 @@ VarDecl::VarDecl(Kind DK, ASTContext &C, DeclContext *DC,
                 "VarDeclBitfields too large!");
   static_assert(sizeof(ParmVarDeclBitfields) <= sizeof(unsigned),
                 "ParmVarDeclBitfields too large!");
+  static_assert(sizeof(NonParmVarDeclBitfields) <= sizeof(unsigned),
+                "NonParmVarDeclBitfields too large!");
   AllBits = 0;
   VarDeclBits.SClass = SC;
   // Everything else is implicitly initialized to false.
@@ -1743,9 +1803,12 @@ void VarDecl::setStorageClass(StorageClass SC) {
 VarDecl::TLSKind VarDecl::getTLSKind() const {
   switch (VarDeclBits.TSCSpec) {
   case TSCS_unspecified:
-    if (hasAttr<ThreadAttr>())
-      return TLS_Static;
-    return TLS_None;
+    if (!hasAttr<ThreadAttr>())
+      return TLS_None;
+    return getASTContext().getLangOpts().isCompatibleWithMSVC(
+               LangOptions::MSVC2015)
+               ? TLS_Dynamic
+               : TLS_Static;
   case TSCS___thread: // Fall through.
   case TSCS__Thread_local:
       return TLS_Static;
@@ -1825,9 +1888,8 @@ bool VarDecl::isInExternCXXContext() const {
 
 VarDecl *VarDecl::getCanonicalDecl() { return getFirstDecl(); }
 
-VarDecl::DefinitionKind VarDecl::isThisDeclarationADefinition(
-  ASTContext &C) const
-{
+VarDecl::DefinitionKind
+VarDecl::isThisDeclarationADefinition(ASTContext &C) const {
   // C++ [basic.def]p2:
   //   A declaration is a definition unless [...] it contains the 'extern'
   //   specifier or a linkage-specification and neither an initializer [...],
@@ -1867,6 +1929,10 @@ VarDecl::DefinitionKind VarDecl::isThisDeclarationADefinition(
   if (hasAttr<AliasAttr>())
     return Definition;
 
+  if (const auto *SAA = getAttr<SelectAnyAttr>())
+    if (!SAA->isInherited())
+      return Definition;
+
   // A variable template specialization (other than a static data member
   // template or an explicit specialization) is a declaration until we
   // instantiate its initializer.
@@ -2460,39 +2526,6 @@ bool FunctionDecl::isReplaceableGlobalAllocationFunction() const {
   return RD && isNamed(RD, "nothrow_t") && RD->isInStdNamespace();
 }
 
-FunctionDecl *
-FunctionDecl::getCorrespondingUnsizedGlobalDeallocationFunction() const {
-  ASTContext &Ctx = getASTContext();
-  if (!Ctx.getLangOpts().SizedDeallocation)
-    return nullptr;
-
-  if (getDeclName().getNameKind() != DeclarationName::CXXOperatorName)
-    return nullptr;
-  if (getDeclName().getCXXOverloadedOperator() != OO_Delete &&
-      getDeclName().getCXXOverloadedOperator() != OO_Array_Delete)
-    return nullptr;
-  if (isa<CXXRecordDecl>(getDeclContext()))
-    return nullptr;
-
-  if (!getDeclContext()->getRedeclContext()->isTranslationUnit())
-    return nullptr;
-
-  if (getNumParams() != 2 || isVariadic() ||
-      !Ctx.hasSameType(getType()->castAs<FunctionProtoType>()->getParamType(1),
-                       Ctx.getSizeType()))
-    return nullptr;
-
-  // This is a sized deallocation function. Find the corresponding unsized
-  // deallocation function.
-  lookup_const_result R = getDeclContext()->lookup(getDeclName());
-  for (lookup_const_result::iterator RI = R.begin(), RE = R.end(); RI != RE;
-       ++RI)
-    if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*RI))
-      if (FD->getNumParams() == 1 && !FD->isVariadic())
-        return FD;
-  return nullptr;
-}
-
 LanguageLinkage FunctionDecl::getLanguageLinkage() const {
   return getDeclLanguageLinkage(*this);
 }
@@ -2550,10 +2583,6 @@ FunctionDecl::setPreviousDeclaration(FunctionDecl *PrevDecl) {
     IsInline = true;
 }
 
-const FunctionDecl *FunctionDecl::getCanonicalDecl() const {
-  return getFirstDecl();
-}
-
 FunctionDecl *FunctionDecl::getCanonicalDecl() { return getFirstDecl(); }
 
 /// \brief Returns a value indicating whether this function
@@ -2581,7 +2610,14 @@ unsigned FunctionDecl::getBuiltinID() const {
     // extern "C".
     // FIXME: A recognised library function may not be directly in an extern "C"
     // declaration, for instance "extern "C" { namespace std { decl } }".
-    if (!LinkageDecl || LinkageDecl->getLanguage() != LinkageSpecDecl::lang_c)
+    if (!LinkageDecl) {
+      if (BuiltinID == Builtin::BI__GetExceptionInfo &&
+          Context.getTargetInfo().getCXXABI().isMicrosoft() &&
+          isInStdNamespace())
+        return Builtin::BI__GetExceptionInfo;
+      return 0;
+    }
+    if (LinkageDecl->getLanguage() != LinkageSpecDecl::lang_c)
       return 0;
   }
 
@@ -2796,6 +2832,18 @@ SourceRange FunctionDecl::getReturnTypeSourceRange() const {
   return RTRange;
 }
 
+bool FunctionDecl::hasUnusedResultAttr() const {
+  QualType RetType = getReturnType();
+  if (RetType->isRecordType()) {
+    const CXXRecordDecl *Ret = RetType->getAsCXXRecordDecl();
+    const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(this);
+    if (Ret && Ret->hasAttr<WarnUnusedResultAttr>() &&
+        !(MD && MD->getCorrespondingMethodInClass(Ret, true)))
+      return true;
+  }
+  return hasAttr<WarnUnusedResultAttr>();
+}
+
 /// \brief For an inline function definition in C, or for a gnu_inline function
 /// in C++, determine whether the definition will be externally visible.
 ///
@@ -3077,6 +3125,8 @@ DependentFunctionTemplateSpecializationInfo::
 DependentFunctionTemplateSpecializationInfo(const UnresolvedSetImpl &Ts,
                                       const TemplateArgumentListInfo &TArgs)
   : AngleLocs(TArgs.getLAngleLoc(), TArgs.getRAngleLoc()) {
+  static_assert(sizeof(*this) % llvm::AlignOf<void *>::Alignment == 0,
+                "Trailing data is unaligned!");
 
   d.NumTemplates = Ts.size();
   d.NumArgs = TArgs.size();
@@ -3590,7 +3640,7 @@ void RecordDecl::completeDefinition() {
 /// This which can be turned on with an attribute, pragma, or the
 /// -mms-bitfields command-line option.
 bool RecordDecl::isMsStruct(const ASTContext &C) const {
-  return hasAttr<MsStructAttr>() || C.getLangOpts().MSBitfields == 1;
+  return hasAttr<MSStructAttr>() || C.getLangOpts().MSBitfields == 1;
 }
 
 static bool isFieldOrIndirectField(Decl::Kind K) {
@@ -3747,6 +3797,13 @@ TranslationUnitDecl *TranslationUnitDecl::Create(ASTContext &C) {
   return new (C, (DeclContext *)nullptr) TranslationUnitDecl(C);
 }
 
+void ExternCContextDecl::anchor() { }
+
+ExternCContextDecl *ExternCContextDecl::Create(const ASTContext &C,
+                                               TranslationUnitDecl *DC) {
+  return new (C, DC) ExternCContextDecl(DC);
+}
+
 void LabelDecl::anchor() { }
 
 LabelDecl *LabelDecl::Create(ASTContext &C, DeclContext *DC,
@@ -3885,6 +3942,21 @@ TypedefDecl *TypedefDecl::Create(ASTContext &C, DeclContext *DC,
 
 void TypedefNameDecl::anchor() { }
 
+TagDecl *TypedefNameDecl::getAnonDeclWithTypedefName(bool AnyRedecl) const {
+  if (auto *TT = getTypeSourceInfo()->getType()->getAs<TagType>()) {
+    auto *OwningTypedef = TT->getDecl()->getTypedefNameForAnonDecl();
+    auto *ThisTypedef = this;
+    if (AnyRedecl && OwningTypedef) {
+      OwningTypedef = OwningTypedef->getCanonicalDecl();
+      ThisTypedef = ThisTypedef->getCanonicalDecl();
+    }
+    if (OwningTypedef == ThisTypedef)
+      return TT->getDecl();
+  }
+
+  return nullptr;
+}
+
 TypedefDecl *TypedefDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
   return new (C, ID) TypedefDecl(C, nullptr, SourceLocation(), SourceLocation(),
                                  nullptr, nullptr);
diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp
index a46787fb0e8f..79cadcfcb167 100644
--- a/lib/AST/DeclBase.cpp
+++ b/lib/AST/DeclBase.cpp
@@ -66,6 +66,12 @@ void *Decl::operator new(std::size_t Size, const ASTContext &Context,
 void *Decl::operator new(std::size_t Size, const ASTContext &Ctx,
                          DeclContext *Parent, std::size_t Extra) {
   assert(!Parent || &Parent->getParentASTContext() == &Ctx);
+  // With local visibility enabled, we track the owning module even for local
+  // declarations.
+  if (Ctx.getLangOpts().ModulesLocalVisibility) {
+    void *Buffer = ::operator new(sizeof(Module *) + Size + Extra, Ctx);
+    return new (Buffer) Module*(nullptr) + 1;
+  }
   return ::operator new(Size + Extra, Ctx);
 }
 
@@ -336,20 +342,34 @@ bool Decl::isReferenced() const {
 static AvailabilityResult CheckAvailability(ASTContext &Context,
                                             const AvailabilityAttr *A,
                                             std::string *Message) {
-  StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
-  StringRef PrettyPlatformName
-    = AvailabilityAttr::getPrettyPlatformName(TargetPlatform);
-  if (PrettyPlatformName.empty())
-    PrettyPlatformName = TargetPlatform;
+  VersionTuple TargetMinVersion =
+    Context.getTargetInfo().getPlatformMinVersion();
 
-  VersionTuple TargetMinVersion = Context.getTargetInfo().getPlatformMinVersion();
   if (TargetMinVersion.empty())
     return AR_Available;
 
+  // Check if this is an App Extension "platform", and if so chop off
+  // the suffix for matching with the actual platform.
+  StringRef ActualPlatform = A->getPlatform()->getName();
+  StringRef RealizedPlatform = ActualPlatform;
+  if (Context.getLangOpts().AppExt) {
+    size_t suffix = RealizedPlatform.rfind("_app_extension");
+    if (suffix != StringRef::npos)
+      RealizedPlatform = RealizedPlatform.slice(0, suffix);
+  }
+
+  StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
+
   // Match the platform name.
-  if (A->getPlatform()->getName() != TargetPlatform)
+  if (RealizedPlatform != TargetPlatform)
     return AR_Available;
-  
+
+  StringRef PrettyPlatformName
+    = AvailabilityAttr::getPrettyPlatformName(ActualPlatform);
+
+  if (PrettyPlatformName.empty())
+    PrettyPlatformName = ActualPlatform;
+
   std::string HintMessage;
   if (!A->getMessage().empty()) {
     HintMessage = " - ";
@@ -583,6 +603,7 @@ unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
     case Block:
     case Captured:
     case TranslationUnit:
+    case ExternCContext:
 
     case UsingDirective:
     case ClassTemplateSpecialization:
@@ -846,6 +867,10 @@ bool DeclContext::isDependentContext() const {
       return getLexicalParent()->isDependentContext();
   }
 
+  // FIXME: A variable template is a dependent context, but is not a
+  // DeclContext. A context within it (such as a lambda-expression)
+  // should be considered dependent.
+
   return getParent() && getParent()->isDependentContext();
 }
 
@@ -889,6 +914,7 @@ bool DeclContext::Encloses(const DeclContext *DC) const {
 DeclContext *DeclContext::getPrimaryContext() {
   switch (DeclKind) {
   case Decl::TranslationUnit:
+  case Decl::ExternCContext:
   case Decl::LinkageSpec:
   case Decl::Block:
   case Decl::Captured:
@@ -991,23 +1017,24 @@ DeclContext::BuildDeclChain(ArrayRef<Decl*> Decls,
 /// built a lookup map. For every name in the map, pull in the new names from
 /// the external storage.
 void DeclContext::reconcileExternalVisibleStorage() const {
-  assert(NeedToReconcileExternalVisibleStorage && LookupPtr.getPointer());
+  assert(NeedToReconcileExternalVisibleStorage && LookupPtr);
   NeedToReconcileExternalVisibleStorage = false;
 
-  for (auto &Lookup : *LookupPtr.getPointer())
+  for (auto &Lookup : *LookupPtr)
     Lookup.second.setHasExternalDecls();
 }
 
 /// \brief Load the declarations within this lexical storage from an
 /// external source.
-void
+/// \return \c true if any declarations were added.
+bool
 DeclContext::LoadLexicalDeclsFromExternalStorage() const {
   ExternalASTSource *Source = getParentASTContext().getExternalSource();
   assert(hasExternalLexicalStorage() && Source && "No external storage?");
 
   // Notify that we have a DeclContext that is initializing.
   ExternalASTSource::Deserializing ADeclContext(Source);
-  
+
   // Load the external declarations, if any.
   SmallVector<Decl*, 64> Decls;
   ExternalLexicalStorage = false;
@@ -1017,11 +1044,11 @@ DeclContext::LoadLexicalDeclsFromExternalStorage() const {
     
   case ELR_Failure:
   case ELR_AlreadyLoaded:
-    return;
+    return false;
   }
 
   if (Decls.empty())
-    return;
+    return false;
 
   // We may have already loaded just the fields of this record, in which case
   // we need to ignore them.
@@ -1038,6 +1065,7 @@ DeclContext::LoadLexicalDeclsFromExternalStorage() const {
   FirstDecl = ExternalFirst;
   if (!LastDecl)
     LastDecl = ExternalLast;
+  return true;
 }
 
 DeclContext::lookup_result
@@ -1045,7 +1073,7 @@ ExternalASTSource::SetNoExternalVisibleDeclsForName(const DeclContext *DC,
                                                     DeclarationName Name) {
   ASTContext &Context = DC->getParentASTContext();
   StoredDeclsMap *Map;
-  if (!(Map = DC->LookupPtr.getPointer()))
+  if (!(Map = DC->LookupPtr))
     Map = DC->CreateStoredDeclsMap(Context);
   if (DC->NeedToReconcileExternalVisibleStorage)
     DC->reconcileExternalVisibleStorage();
@@ -1061,7 +1089,7 @@ ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
                                                   ArrayRef<NamedDecl*> Decls) {
   ASTContext &Context = DC->getParentASTContext();
   StoredDeclsMap *Map;
-  if (!(Map = DC->LookupPtr.getPointer()))
+  if (!(Map = DC->LookupPtr))
     Map = DC->CreateStoredDeclsMap(Context);
   if (DC->NeedToReconcileExternalVisibleStorage)
     DC->reconcileExternalVisibleStorage();
@@ -1078,7 +1106,7 @@ ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
     // first.
     llvm::SmallVector<unsigned, 8> Skip;
     for (unsigned I = 0, N = Decls.size(); I != N; ++I)
-      if (List.HandleRedeclaration(Decls[I]))
+      if (List.HandleRedeclaration(Decls[I], /*IsKnownNewer*/false))
         Skip.push_back(I);
     Skip.push_back(Decls.size());
 
@@ -1155,7 +1183,7 @@ void DeclContext::removeDecl(Decl *D) {
     // Remove only decls that have a name
     if (!ND->getDeclName()) return;
 
-    StoredDeclsMap *Map = getPrimaryContext()->LookupPtr.getPointer();
+    StoredDeclsMap *Map = getPrimaryContext()->LookupPtr;
     if (!Map) return;
 
     StoredDeclsMap::iterator Pos = Map->find(ND->getDeclName());
@@ -1243,32 +1271,38 @@ static bool shouldBeHidden(NamedDecl *D) {
 StoredDeclsMap *DeclContext::buildLookup() {
   assert(this == getPrimaryContext() && "buildLookup called on non-primary DC");
 
-  // FIXME: Should we keep going if hasExternalVisibleStorage?
-  if (!LookupPtr.getInt())
-    return LookupPtr.getPointer();
+  if (!HasLazyLocalLexicalLookups && !HasLazyExternalLexicalLookups)
+    return LookupPtr;
 
   SmallVector<DeclContext *, 2> Contexts;
   collectAllContexts(Contexts);
-  for (unsigned I = 0, N = Contexts.size(); I != N; ++I)
-    buildLookupImpl<&DeclContext::decls_begin,
-                    &DeclContext::decls_end>(Contexts[I]);
+
+  if (HasLazyExternalLexicalLookups) {
+    HasLazyExternalLexicalLookups = false;
+    for (auto *DC : Contexts) {
+      if (DC->hasExternalLexicalStorage())
+        HasLazyLocalLexicalLookups |=
+            DC->LoadLexicalDeclsFromExternalStorage();
+    }
+
+    if (!HasLazyLocalLexicalLookups)
+      return LookupPtr;
+  }
+
+  for (auto *DC : Contexts)
+    buildLookupImpl(DC, hasExternalVisibleStorage());
 
   // We no longer have any lazy decls.
-  LookupPtr.setInt(false);
-  return LookupPtr.getPointer();
+  HasLazyLocalLexicalLookups = false;
+  return LookupPtr;
 }
 
 /// buildLookupImpl - Build part of the lookup data structure for the
 /// declarations contained within DCtx, which will either be this
 /// DeclContext, a DeclContext linked to it, or a transparent context
 /// nested within it.
-template<DeclContext::decl_iterator (DeclContext::*Begin)() const,
-         DeclContext::decl_iterator (DeclContext::*End)() const>
-void DeclContext::buildLookupImpl(DeclContext *DCtx) {
-  for (decl_iterator I = (DCtx->*Begin)(), E = (DCtx->*End)();
-       I != E; ++I) {
-    Decl *D = *I;
-
+void DeclContext::buildLookupImpl(DeclContext *DCtx, bool Internal) {
+  for (Decl *D : DCtx->noload_decls()) {
     // Insert this declaration into the lookup structure, but only if
     // it's semantically within its decl context. Any other decls which
     // should be found in this context are added eagerly.
@@ -1282,39 +1316,46 @@ void DeclContext::buildLookupImpl(DeclContext *DCtx) {
           (!ND->isFromASTFile() ||
            (isTranslationUnit() &&
             !getParentASTContext().getLangOpts().CPlusPlus)))
-        makeDeclVisibleInContextImpl(ND, false);
+        makeDeclVisibleInContextImpl(ND, Internal);
 
     // If this declaration is itself a transparent declaration context
     // or inline namespace, add the members of this declaration of that
     // context (recursively).
     if (DeclContext *InnerCtx = dyn_cast<DeclContext>(D))
       if (InnerCtx->isTransparentContext() || InnerCtx->isInlineNamespace())
-        buildLookupImpl<Begin, End>(InnerCtx);
+        buildLookupImpl(InnerCtx, Internal);
   }
 }
 
+NamedDecl *const DeclContextLookupResult::SingleElementDummyList = nullptr;
+
 DeclContext::lookup_result
-DeclContext::lookup(DeclarationName Name) {
+DeclContext::lookup(DeclarationName Name) const {
   assert(DeclKind != Decl::LinkageSpec &&
          "Should not perform lookups into linkage specs!");
 
-  DeclContext *PrimaryContext = getPrimaryContext();
+  const DeclContext *PrimaryContext = getPrimaryContext();
   if (PrimaryContext != this)
     return PrimaryContext->lookup(Name);
 
-  // If this is a namespace, ensure that any later redeclarations of it have
-  // been loaded, since they may add names to the result of this lookup.
-  if (auto *ND = dyn_cast<NamespaceDecl>(this))
-    (void)ND->getMostRecentDecl();
+  // If we have an external source, ensure that any later redeclarations of this
+  // context have been loaded, since they may add names to the result of this
+  // lookup (or add external visible storage).
+  ExternalASTSource *Source = getParentASTContext().getExternalSource();
+  if (Source)
+    (void)cast<Decl>(this)->getMostRecentDecl();
 
   if (hasExternalVisibleStorage()) {
+    assert(Source && "external visible storage but no external source?");
+
     if (NeedToReconcileExternalVisibleStorage)
       reconcileExternalVisibleStorage();
 
-    StoredDeclsMap *Map = LookupPtr.getPointer();
+    StoredDeclsMap *Map = LookupPtr;
 
-    if (LookupPtr.getInt())
-      Map = buildLookup();
+    if (HasLazyLocalLexicalLookups || HasLazyExternalLexicalLookups)
+      // FIXME: Make buildLookup const?
+      Map = const_cast<DeclContext*>(this)->buildLookup();
 
     if (!Map)
       Map = CreateStoredDeclsMap(getParentASTContext());
@@ -1325,28 +1366,27 @@ DeclContext::lookup(DeclarationName Name) {
     if (!R.second && !R.first->second.hasExternalDecls())
       return R.first->second.getLookupResult();
 
-    ExternalASTSource *Source = getParentASTContext().getExternalSource();
     if (Source->FindExternalVisibleDeclsByName(this, Name) || !R.second) {
-      if (StoredDeclsMap *Map = LookupPtr.getPointer()) {
+      if (StoredDeclsMap *Map = LookupPtr) {
         StoredDeclsMap::iterator I = Map->find(Name);
         if (I != Map->end())
           return I->second.getLookupResult();
       }
     }
 
-    return lookup_result(lookup_iterator(nullptr), lookup_iterator(nullptr));
+    return lookup_result();
   }
 
-  StoredDeclsMap *Map = LookupPtr.getPointer();
-  if (LookupPtr.getInt())
-    Map = buildLookup();
+  StoredDeclsMap *Map = LookupPtr;
+  if (HasLazyLocalLexicalLookups || HasLazyExternalLexicalLookups)
+    Map = const_cast<DeclContext*>(this)->buildLookup();
 
   if (!Map)
-    return lookup_result(lookup_iterator(nullptr), lookup_iterator(nullptr));
+    return lookup_result();
 
   StoredDeclsMap::iterator I = Map->find(Name);
   if (I == Map->end())
-    return lookup_result(lookup_iterator(nullptr), lookup_iterator(nullptr));
+    return lookup_result();
 
   return I->second.getLookupResult();
 }
@@ -1355,40 +1395,29 @@ DeclContext::lookup_result
 DeclContext::noload_lookup(DeclarationName Name) {
   assert(DeclKind != Decl::LinkageSpec &&
          "Should not perform lookups into linkage specs!");
-  if (!hasExternalVisibleStorage())
-    return lookup(Name);
 
   DeclContext *PrimaryContext = getPrimaryContext();
   if (PrimaryContext != this)
     return PrimaryContext->noload_lookup(Name);
 
-  StoredDeclsMap *Map = LookupPtr.getPointer();
-  if (LookupPtr.getInt()) {
-    // Carefully build the lookup map, without deserializing anything.
+  // If we have any lazy lexical declarations not in our lookup map, add them
+  // now. Don't import any external declarations, not even if we know we have
+  // some missing from the external visible lookups.
+  if (HasLazyLocalLexicalLookups) {
     SmallVector<DeclContext *, 2> Contexts;
     collectAllContexts(Contexts);
     for (unsigned I = 0, N = Contexts.size(); I != N; ++I)
-      buildLookupImpl<&DeclContext::noload_decls_begin,
-                      &DeclContext::noload_decls_end>(Contexts[I]);
-
-    // We no longer have any lazy decls.
-    LookupPtr.setInt(false);
-
-    // There may now be names for which we have local decls but are
-    // missing the external decls. FIXME: Just set the hasExternalDecls
-    // flag on those names that have external decls.
-    NeedToReconcileExternalVisibleStorage = true;
-
-    Map = LookupPtr.getPointer();
+      buildLookupImpl(Contexts[I], hasExternalVisibleStorage());
+    HasLazyLocalLexicalLookups = false;
   }
 
+  StoredDeclsMap *Map = LookupPtr;
   if (!Map)
-    return lookup_result(lookup_iterator(nullptr), lookup_iterator(nullptr));
+    return lookup_result();
 
   StoredDeclsMap::iterator I = Map->find(Name);
   return I != Map->end() ? I->second.getLookupResult()
-                         : lookup_result(lookup_iterator(nullptr),
-                                         lookup_iterator(nullptr));
+                         : lookup_result();
 }
 
 void DeclContext::localUncachedLookup(DeclarationName Name,
@@ -1404,8 +1433,9 @@ void DeclContext::localUncachedLookup(DeclarationName Name,
   }
 
   // If we have a lookup table, check there first. Maybe we'll get lucky.
-  if (Name && !LookupPtr.getInt()) {
-    if (StoredDeclsMap *Map = LookupPtr.getPointer()) {
+  // FIXME: Should we be checking these flags on the primary context?
+  if (Name && !HasLazyLocalLexicalLookups && !HasLazyExternalLexicalLookups) {
+    if (StoredDeclsMap *Map = LookupPtr) {
       StoredDeclsMap::iterator Pos = Map->find(Name);
       if (Pos != Map->end()) {
         Results.insert(Results.end(),
@@ -1418,6 +1448,8 @@ void DeclContext::localUncachedLookup(DeclarationName Name,
 
   // Slow case: grovel through the declarations in our chain looking for 
   // matches.
+  // FIXME: If we have lazy external declarations, this will not find them!
+  // FIXME: Should we CollectAllContexts and walk them all here?
   for (Decl *D = FirstDecl; D; D = D->getNextDeclInContext()) {
     if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
       if (ND->getDeclName() == Name)
@@ -1498,7 +1530,7 @@ void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
   // FIXME: As a performance hack, don't add such decls into the translation
   // unit unless we're in C++, since qualified lookup into the TU is never
   // performed.
-  if (LookupPtr.getPointer() || hasExternalVisibleStorage() ||
+  if (LookupPtr || hasExternalVisibleStorage() ||
       ((!Recoverable || D->getDeclContext() != D->getLexicalDeclContext()) &&
        (getParentASTContext().getLangOpts().CPlusPlus ||
         !isTranslationUnit()))) {
@@ -1508,7 +1540,7 @@ void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
     buildLookup();
     makeDeclVisibleInContextImpl(D, Internal);
   } else {
-    LookupPtr.setInt(true);
+    HasLazyLocalLexicalLookups = true;
   }
 
   // If we are a transparent context or inline namespace, insert into our
@@ -1526,7 +1558,7 @@ void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
 
 void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
   // Find or create the stored declaration map.
-  StoredDeclsMap *Map = LookupPtr.getPointer();
+  StoredDeclsMap *Map = LookupPtr;
   if (!Map) {
     ASTContext *C = &getParentASTContext();
     Map = CreateStoredDeclsMap(*C);
@@ -1555,12 +1587,12 @@ void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
     return;
   }
 
-  else if (DeclNameEntries.isNull()) {
+  if (DeclNameEntries.isNull()) {
     DeclNameEntries.setOnlyValue(D);
     return;
   }
 
-  if (DeclNameEntries.HandleRedeclaration(D)) {
+  if (DeclNameEntries.HandleRedeclaration(D, /*IsKnownNewer*/!Internal)) {
     // This declaration has replaced an existing one for which
     // declarationReplaces returns true.
     return;
@@ -1570,15 +1602,17 @@ void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
   DeclNameEntries.AddSubsequentDecl(D);
 }
 
+UsingDirectiveDecl *DeclContext::udir_iterator::operator*() const {
+  return cast<UsingDirectiveDecl>(*I);
+}
+
 /// Returns iterator range [First, Last) of UsingDirectiveDecls stored within
 /// this context.
 DeclContext::udir_range DeclContext::using_directives() const {
   // FIXME: Use something more efficient than normal lookup for using
   // directives. In C++, using directives are looked up more than anything else.
-  lookup_const_result Result = lookup(UsingDirectiveDecl::getName());
-  return udir_range(
-      reinterpret_cast<UsingDirectiveDecl *const *>(Result.begin()),
-      reinterpret_cast<UsingDirectiveDecl *const *>(Result.end()));
+  lookup_result Result = lookup(UsingDirectiveDecl::getName());
+  return udir_range(Result.begin(), Result.end());
 }
 
 //===----------------------------------------------------------------------===//
@@ -1586,7 +1620,7 @@ DeclContext::udir_range DeclContext::using_directives() const {
 //===----------------------------------------------------------------------===//
 
 StoredDeclsMap *DeclContext::CreateStoredDeclsMap(ASTContext &C) const {
-  assert(!LookupPtr.getPointer() && "context already has a decls map");
+  assert(!LookupPtr && "context already has a decls map");
   assert(getPrimaryContext() == this &&
          "creating decls map on non-primary context");
 
@@ -1598,7 +1632,7 @@ StoredDeclsMap *DeclContext::CreateStoredDeclsMap(ASTContext &C) const {
     M = new StoredDeclsMap();
   M->Previous = C.LastSDM;
   C.LastSDM = llvm::PointerIntPair<StoredDeclsMap*,1>(M, Dependent);
-  LookupPtr.setPointer(M);
+  LookupPtr = M;
   return M;
 }
 
@@ -1630,11 +1664,11 @@ DependentDiagnostic *DependentDiagnostic::Create(ASTContext &C,
   assert(Parent->isDependentContext()
          && "cannot iterate dependent diagnostics of non-dependent context");
   Parent = Parent->getPrimaryContext();
-  if (!Parent->LookupPtr.getPointer())
+  if (!Parent->LookupPtr)
     Parent->CreateStoredDeclsMap(C);
 
-  DependentStoredDeclsMap *Map
-    = static_cast<DependentStoredDeclsMap*>(Parent->LookupPtr.getPointer());
+  DependentStoredDeclsMap *Map =
+      static_cast<DependentStoredDeclsMap *>(Parent->LookupPtr);
 
   // Allocate the copy of the PartialDiagnostic via the ASTContext's
   // BumpPtrAllocator, rather than the ASTContext itself.
diff --git a/lib/AST/DeclCXX.cpp b/lib/AST/DeclCXX.cpp
index 9af8c4b242a6..8dc62dd07f2c 100644
--- a/lib/AST/DeclCXX.cpp
+++ b/lib/AST/DeclCXX.cpp
@@ -991,7 +991,7 @@ CXXMethodDecl* CXXRecordDecl::getLambdaCallOperator() const {
   if (!isLambda()) return nullptr;
   DeclarationName Name = 
     getASTContext().DeclarationNames.getCXXOperatorName(OO_Call);
-  DeclContext::lookup_const_result Calls = lookup(Name);
+  DeclContext::lookup_result Calls = lookup(Name);
 
   assert(!Calls.empty() && "Missing lambda call operator!");
   assert(Calls.size() == 1 && "More than one lambda call operator!"); 
@@ -1008,7 +1008,7 @@ CXXMethodDecl* CXXRecordDecl::getLambdaStaticInvoker() const {
   if (!isLambda()) return nullptr;
   DeclarationName Name = 
     &getASTContext().Idents.get(getLambdaStaticInvokerName());
-  DeclContext::lookup_const_result Invoker = lookup(Name);
+  DeclContext::lookup_result Invoker = lookup(Name);
   if (Invoker.empty()) return nullptr;
   assert(Invoker.size() == 1 && "More than one static invoker operator!");  
   NamedDecl *InvokerFun = Invoker.front();
@@ -1173,7 +1173,7 @@ static void CollectVisibleConversions(ASTContext &Context,
 
 /// getVisibleConversionFunctions - get all conversion functions visible
 /// in current class; including conversion function templates.
-std::pair<CXXRecordDecl::conversion_iterator,CXXRecordDecl::conversion_iterator>
+llvm::iterator_range<CXXRecordDecl::conversion_iterator>
 CXXRecordDecl::getVisibleConversionFunctions() {
   ASTContext &Ctx = getASTContext();
 
@@ -1189,7 +1189,7 @@ CXXRecordDecl::getVisibleConversionFunctions() {
       data().ComputedVisibleConversions = true;
     }
   }
-  return std::make_pair(Set->begin(), Set->end());
+  return llvm::make_range(Set->begin(), Set->end());
 }
 
 void CXXRecordDecl::removeConversion(const NamedDecl *ConvDecl) {
@@ -1307,7 +1307,7 @@ CXXDestructorDecl *CXXRecordDecl::getDestructor() const {
     = Context.DeclarationNames.getCXXDestructorName(
                                           Context.getCanonicalType(ClassType));
 
-  DeclContext::lookup_const_result R = lookup(Name);
+  DeclContext::lookup_result R = lookup(Name);
   if (R.empty())
     return nullptr;
 
@@ -1418,9 +1418,8 @@ CXXMethodDecl::getCorrespondingMethodInClass(const CXXRecordDecl *RD,
     return nullptr;
   }
 
-  lookup_const_result Candidates = RD->lookup(getDeclName());
-  for (NamedDecl * const * I = Candidates.begin(); I != Candidates.end(); ++I) {
-    CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*I);
+  for (auto *ND : RD->lookup(getDeclName())) {
+    CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND);
     if (!MD)
       continue;
     if (recursivelyOverrides(MD, this))
@@ -1491,8 +1490,8 @@ bool CXXMethodDecl::isUsualDeallocationFunction() const {
                  
   // This function is a usual deallocation function if there are no 
   // single-parameter deallocation functions of the same kind.
-  DeclContext::lookup_const_result R = getDeclContext()->lookup(getDeclName());
-  for (DeclContext::lookup_const_result::iterator I = R.begin(), E = R.end();
+  DeclContext::lookup_result R = getDeclContext()->lookup(getDeclName());
+  for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
        I != E; ++I) {
     if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(*I))
       if (FD->getNumParams() == 1)
@@ -1740,6 +1739,10 @@ CXXConstructorDecl::Create(ASTContext &C, CXXRecordDecl *RD,
                                         isImplicitlyDeclared, isConstexpr);
 }
 
+CXXConstructorDecl::init_const_iterator CXXConstructorDecl::init_begin() const {
+  return CtorInitializers.get(getASTContext().getExternalSource());
+}
+
 CXXConstructorDecl *CXXConstructorDecl::getTargetConstructor() const {
   assert(isDelegatingConstructor() && "Not a delegating constructor!");
   Expr *E = (*init_begin())->getInit()->IgnoreImplicit();
@@ -1887,6 +1890,15 @@ CXXDestructorDecl::Create(ASTContext &C, CXXRecordDecl *RD,
                                        isInline, isImplicitlyDeclared);
 }
 
+void CXXDestructorDecl::setOperatorDelete(FunctionDecl *OD) {
+  auto *First = cast<CXXDestructorDecl>(getFirstDecl());
+  if (OD && !First->OperatorDelete) {
+    First->OperatorDelete = OD;
+    if (auto *L = getASTMutationListener())
+      L->ResolvedOperatorDelete(First, OD);
+  }
+}
+
 void CXXConversionDecl::anchor() { }
 
 CXXConversionDecl *
diff --git a/lib/AST/DeclGroup.cpp b/lib/AST/DeclGroup.cpp
index 9861f2278f9a..512837fdf3f4 100644
--- a/lib/AST/DeclGroup.cpp
+++ b/lib/AST/DeclGroup.cpp
@@ -18,6 +18,8 @@
 using namespace clang;
 
 DeclGroup* DeclGroup::Create(ASTContext &C, Decl **Decls, unsigned NumDecls) {
+  static_assert(sizeof(DeclGroup) % llvm::AlignOf<void *>::Alignment == 0,
+                "Trailing data is unaligned!");
   assert(NumDecls > 1 && "Invalid DeclGroup");
   unsigned Size = sizeof(DeclGroup) + sizeof(Decl*) * NumDecls;
   void* Mem = C.Allocate(Size, llvm::AlignOf<DeclGroup>::Alignment);
diff --git a/lib/AST/DeclObjC.cpp b/lib/AST/DeclObjC.cpp
index ed5367514c30..a63ba7e698a8 100644
--- a/lib/AST/DeclObjC.cpp
+++ b/lib/AST/DeclObjC.cpp
@@ -54,8 +54,8 @@ void ObjCContainerDecl::anchor() { }
 ///
 ObjCIvarDecl *
 ObjCContainerDecl::getIvarDecl(IdentifierInfo *Id) const {
-  lookup_const_result R = lookup(Id);
-  for (lookup_const_iterator Ivar = R.begin(), IvarEnd = R.end();
+  lookup_result R = lookup(Id);
+  for (lookup_iterator Ivar = R.begin(), IvarEnd = R.end();
        Ivar != IvarEnd; ++Ivar) {
     if (ObjCIvarDecl *ivar = dyn_cast<ObjCIvarDecl>(*Ivar))
       return ivar;
@@ -83,8 +83,8 @@ ObjCContainerDecl::getMethod(Selector Sel, bool isInstance,
   // + (float) class_method;
   // @end
   //
-  lookup_const_result R = lookup(Sel);
-  for (lookup_const_iterator Meth = R.begin(), MethEnd = R.end();
+  lookup_result R = lookup(Sel);
+  for (lookup_iterator Meth = R.begin(), MethEnd = R.end();
        Meth != MethEnd; ++Meth) {
     ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(*Meth);
     if (MD && MD->isInstanceMethod() == isInstance)
@@ -101,8 +101,8 @@ ObjCContainerDecl::getMethod(Selector Sel, bool isInstance,
 bool ObjCContainerDecl::HasUserDeclaredSetterMethod(
     const ObjCPropertyDecl *Property) const {
   Selector Sel = Property->getSetterName();
-  lookup_const_result R = lookup(Sel);
-  for (lookup_const_iterator Meth = R.begin(), MethEnd = R.end();
+  lookup_result R = lookup(Sel);
+  for (lookup_iterator Meth = R.begin(), MethEnd = R.end();
        Meth != MethEnd; ++Meth) {
     ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(*Meth);
     if (MD && MD->isInstanceMethod() && !MD->isImplicit())
@@ -161,8 +161,8 @@ ObjCPropertyDecl::findPropertyDecl(const DeclContext *DC,
         return nullptr;
   }
 
-  DeclContext::lookup_const_result R = DC->lookup(propertyID);
-  for (DeclContext::lookup_const_iterator I = R.begin(), E = R.end(); I != E;
+  DeclContext::lookup_result R = DC->lookup(propertyID);
+  for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
        ++I)
     if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(*I))
       return PD;
@@ -334,9 +334,8 @@ void ObjCInterfaceDecl::mergeClassExtensionProtocolList(
     return;
 
   // Merge ProtocolRefs into class's protocol list;
-  for (auto *P : all_referenced_protocols()) {
-    ProtocolRefs.push_back(P);
-  }
+  ProtocolRefs.append(all_referenced_protocol_begin(),
+                      all_referenced_protocol_end());
 
   data().AllReferencedProtocols.set(ProtocolRefs.data(), ProtocolRefs.size(),C);
 }
@@ -617,8 +616,7 @@ ObjCMethodDecl *ObjCInterfaceDecl::lookupPrivateMethod(
 
   // Look through local category implementations associated with the class.
   if (!Method)
-    Method = Instance ? getCategoryInstanceMethod(Sel)
-                      : getCategoryClassMethod(Sel);
+    Method = getCategoryMethod(Sel, Instance);
 
   // Before we give up, check if the selector is an instance method.
   // But only in the root. This matches gcc's behavior and what the
@@ -1101,7 +1099,7 @@ ObjCMethodDecl::findPropertyDecl(bool CheckOverrides) const {
   if (NumArgs > 1)
     return nullptr;
 
-  if (!isInstanceMethod() || getMethodFamily() != OMF_None)
+  if (!isInstanceMethod())
     return nullptr;
 
   if (isPropertyAccessor()) {
@@ -1822,6 +1820,11 @@ void ObjCImplementationDecl::setIvarInitializers(ASTContext &C,
   }
 }
 
+ObjCImplementationDecl::init_const_iterator
+ObjCImplementationDecl::init_begin() const {
+  return IvarInitializers.get(getASTContext().getExternalSource());
+}
+
 raw_ostream &clang::operator<<(raw_ostream &OS,
                                const ObjCImplementationDecl &ID) {
   OS << ID.getName();
diff --git a/lib/AST/DeclTemplate.cpp b/lib/AST/DeclTemplate.cpp
index 0d1d2a4613dc..6374a92621a4 100644
--- a/lib/AST/DeclTemplate.cpp
+++ b/lib/AST/DeclTemplate.cpp
@@ -160,17 +160,43 @@ RedeclarableTemplateDecl::CommonBase *RedeclarableTemplateDecl::getCommonPtr() c
   return Common;
 }
 
-template <class EntryType>
-typename RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::DeclType*
+template<class EntryType>
+typename RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::DeclType *
 RedeclarableTemplateDecl::findSpecializationImpl(
-                                 llvm::FoldingSetVector<EntryType> &Specs,
-                                 ArrayRef<TemplateArgument> Args,
-                                 void *&InsertPos) {
+    llvm::FoldingSetVector<EntryType> &Specs, ArrayRef<TemplateArgument> Args,
+    void *&InsertPos) {
   typedef SpecEntryTraits<EntryType> SETraits;
   llvm::FoldingSetNodeID ID;
   EntryType::Profile(ID,Args, getASTContext());
   EntryType *Entry = Specs.FindNodeOrInsertPos(ID, InsertPos);
-  return Entry ? SETraits::getMostRecentDecl(Entry) : nullptr;
+  return Entry ? SETraits::getDecl(Entry)->getMostRecentDecl() : nullptr;
+}
+
+template<class Derived, class EntryType>
+void RedeclarableTemplateDecl::addSpecializationImpl(
+    llvm::FoldingSetVector<EntryType> &Specializations, EntryType *Entry,
+    void *InsertPos) {
+  typedef SpecEntryTraits<EntryType> SETraits;
+  if (InsertPos) {
+#ifndef NDEBUG
+    void *CorrectInsertPos;
+    assert(!findSpecializationImpl(Specializations,
+                                   SETraits::getTemplateArgs(Entry),
+                                   CorrectInsertPos) &&
+           InsertPos == CorrectInsertPos &&
+           "given incorrect InsertPos for specialization");
+#endif
+    Specializations.InsertNode(Entry, InsertPos);
+  } else {
+    EntryType *Existing = Specializations.GetOrInsertNode(Entry);
+    (void)Existing;
+    assert(SETraits::getDecl(Existing)->isCanonicalDecl() &&
+           "non-canonical specialization?");
+  }
+
+  if (ASTMutationListener *L = getASTMutationListener())
+    L->AddedCXXTemplateSpecialization(cast<Derived>(this),
+                                      SETraits::getDecl(Entry));
 }
 
 /// \brief Generate the injected template arguments for the given template
@@ -246,7 +272,11 @@ FunctionTemplateDecl::newCommon(ASTContext &C) const {
 }
 
 void FunctionTemplateDecl::LoadLazySpecializations() const {
-  Common *CommonPtr = getCommonPtr();
+  // Grab the most recent declaration to ensure we've loaded any lazy
+  // redeclarations of this template.
+  //
+  // FIXME: Avoid walking the entire redeclaration chain here.
+  Common *CommonPtr = getMostRecentDecl()->getCommonPtr();
   if (CommonPtr->LazySpecializations) {
     ASTContext &Context = getASTContext();
     uint32_t *Specs = CommonPtr->LazySpecializations;
@@ -270,12 +300,8 @@ FunctionTemplateDecl::findSpecialization(ArrayRef<TemplateArgument> Args,
 
 void FunctionTemplateDecl::addSpecialization(
       FunctionTemplateSpecializationInfo *Info, void *InsertPos) {
-  if (InsertPos)
-    getSpecializations().InsertNode(Info, InsertPos);
-  else
-    getSpecializations().GetOrInsertNode(Info);
-  if (ASTMutationListener *L = getASTMutationListener())
-    L->AddedCXXTemplateSpecialization(this, Info->Function);
+  addSpecializationImpl<FunctionTemplateDecl>(getSpecializations(), Info,
+                                              InsertPos);
 }
 
 ArrayRef<TemplateArgument> FunctionTemplateDecl::getInjectedTemplateArgs() {
@@ -320,7 +346,11 @@ ClassTemplateDecl *ClassTemplateDecl::CreateDeserialized(ASTContext &C,
 }
 
 void ClassTemplateDecl::LoadLazySpecializations() const {
-  Common *CommonPtr = getCommonPtr();
+  // Grab the most recent declaration to ensure we've loaded any lazy
+  // redeclarations of this template.
+  //
+  // FIXME: Avoid walking the entire redeclaration chain here.
+  Common *CommonPtr = getMostRecentDecl()->getCommonPtr();
   if (CommonPtr->LazySpecializations) {
     ASTContext &Context = getASTContext();
     uint32_t *Specs = CommonPtr->LazySpecializations;
@@ -357,16 +387,7 @@ ClassTemplateDecl::findSpecialization(ArrayRef<TemplateArgument> Args,
 
 void ClassTemplateDecl::AddSpecialization(ClassTemplateSpecializationDecl *D,
                                           void *InsertPos) {
-  if (InsertPos)
-    getSpecializations().InsertNode(D, InsertPos);
-  else {
-    ClassTemplateSpecializationDecl *Existing 
-      = getSpecializations().GetOrInsertNode(D);
-    (void)Existing;
-    assert(Existing->isCanonicalDecl() && "Non-canonical specialization?");
-  }
-  if (ASTMutationListener *L = getASTMutationListener())
-    L->AddedCXXTemplateSpecialization(this, D);
+  addSpecializationImpl<ClassTemplateDecl>(getSpecializations(), D, InsertPos);
 }
 
 ClassTemplatePartialSpecializationDecl *
@@ -953,7 +974,11 @@ VarTemplateDecl *VarTemplateDecl::CreateDeserialized(ASTContext &C,
 // TODO: Unify across class, function and variable templates?
 //       May require moving this and Common to RedeclarableTemplateDecl.
 void VarTemplateDecl::LoadLazySpecializations() const {
-  Common *CommonPtr = getCommonPtr();
+  // Grab the most recent declaration to ensure we've loaded any lazy
+  // redeclarations of this template.
+  //
+  // FIXME: Avoid walking the entire redeclaration chain here.
+  Common *CommonPtr = getMostRecentDecl()->getCommonPtr();
   if (CommonPtr->LazySpecializations) {
     ASTContext &Context = getASTContext();
     uint32_t *Specs = CommonPtr->LazySpecializations;
@@ -990,16 +1015,7 @@ VarTemplateDecl::findSpecialization(ArrayRef<TemplateArgument> Args,
 
 void VarTemplateDecl::AddSpecialization(VarTemplateSpecializationDecl *D,
                                         void *InsertPos) {
-  if (InsertPos)
-    getSpecializations().InsertNode(D, InsertPos);
-  else {
-    VarTemplateSpecializationDecl *Existing =
-        getSpecializations().GetOrInsertNode(D);
-    (void)Existing;
-    assert(Existing->isCanonicalDecl() && "Non-canonical specialization?");
-  }
-  if (ASTMutationListener *L = getASTMutationListener())
-    L->AddedCXXTemplateSpecialization(this, D);
+  addSpecializationImpl<VarTemplateDecl>(getSpecializations(), D, InsertPos);
 }
 
 VarTemplatePartialSpecializationDecl *
diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 712de5056e8d..76a4da2371b5 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -1141,40 +1141,13 @@ CallExpr::CallExpr(const ASTContext& C, StmtClass SC, Expr *fn,
   RParenLoc = rparenloc;
 }
 
-CallExpr::CallExpr(const ASTContext& C, Expr *fn, ArrayRef<Expr*> args,
+CallExpr::CallExpr(const ASTContext &C, Expr *fn, ArrayRef<Expr *> args,
                    QualType t, ExprValueKind VK, SourceLocation rparenloc)
-  : Expr(CallExprClass, t, VK, OK_Ordinary,
-         fn->isTypeDependent(),
-         fn->isValueDependent(),
-         fn->isInstantiationDependent(),
-         fn->containsUnexpandedParameterPack()),
-    NumArgs(args.size()) {
-
-  SubExprs = new (C) Stmt*[args.size()+PREARGS_START];
-  SubExprs[FN] = fn;
-  for (unsigned i = 0; i != args.size(); ++i) {
-    if (args[i]->isTypeDependent())
-      ExprBits.TypeDependent = true;
-    if (args[i]->isValueDependent())
-      ExprBits.ValueDependent = true;
-    if (args[i]->isInstantiationDependent())
-      ExprBits.InstantiationDependent = true;
-    if (args[i]->containsUnexpandedParameterPack())
-      ExprBits.ContainsUnexpandedParameterPack = true;
-
-    SubExprs[i+PREARGS_START] = args[i];
-  }
-
-  CallExprBits.NumPreArgs = 0;
-  RParenLoc = rparenloc;
+    : CallExpr(C, CallExprClass, fn, /*NumPreArgs=*/0, args, t, VK, rparenloc) {
 }
 
 CallExpr::CallExpr(const ASTContext &C, StmtClass SC, EmptyShell Empty)
-  : Expr(SC, Empty), SubExprs(nullptr), NumArgs(0) {
-  // FIXME: Why do we allocate this?
-  SubExprs = new (C) Stmt*[PREARGS_START];
-  CallExprBits.NumPreArgs = 0;
-}
+    : CallExpr(C, SC, /*NumPreArgs=*/0, Empty) {}
 
 CallExpr::CallExpr(const ASTContext &C, StmtClass SC, unsigned NumPreArgs,
                    EmptyShell Empty)
@@ -1271,16 +1244,21 @@ bool CallExpr::isUnevaluatedBuiltinCall(ASTContext &Ctx) const {
   return false;
 }
 
-QualType CallExpr::getCallReturnType() const {
-  QualType CalleeType = getCallee()->getType();
-  if (const PointerType *FnTypePtr = CalleeType->getAs<PointerType>())
+QualType CallExpr::getCallReturnType(const ASTContext &Ctx) const {
+  const Expr *Callee = getCallee();
+  QualType CalleeType = Callee->getType();
+  if (const auto *FnTypePtr = CalleeType->getAs<PointerType>()) {
     CalleeType = FnTypePtr->getPointeeType();
-  else if (const BlockPointerType *BPT = CalleeType->getAs<BlockPointerType>())
+  } else if (const auto *BPT = CalleeType->getAs<BlockPointerType>()) {
     CalleeType = BPT->getPointeeType();
-  else if (CalleeType->isSpecificPlaceholderType(BuiltinType::BoundMember))
+  } else if (CalleeType->isSpecificPlaceholderType(BuiltinType::BoundMember)) {
+    if (isa<CXXPseudoDestructorExpr>(Callee->IgnoreParens()))
+      return Ctx.VoidTy;
+
     // This should never be overloaded and so should never return null.
-    CalleeType = Expr::findBoundMemberType(getCallee());
-    
+    CalleeType = Expr::findBoundMemberType(Callee);
+  }
+
   const FunctionType *FnType = CalleeType->castAs<FunctionType>();
   return FnType->getReturnType();
 }
@@ -1360,16 +1338,50 @@ IdentifierInfo *OffsetOfExpr::OffsetOfNode::getFieldName() const {
   return reinterpret_cast<IdentifierInfo *> (Data & ~(uintptr_t)Mask);
 }
 
-MemberExpr *MemberExpr::Create(const ASTContext &C, Expr *base, bool isarrow,
-                               NestedNameSpecifierLoc QualifierLoc,
-                               SourceLocation TemplateKWLoc,
-                               ValueDecl *memberdecl,
-                               DeclAccessPair founddecl,
-                               DeclarationNameInfo nameinfo,
-                               const TemplateArgumentListInfo *targs,
-                               QualType ty,
-                               ExprValueKind vk,
-                               ExprObjectKind ok) {
+UnaryExprOrTypeTraitExpr::UnaryExprOrTypeTraitExpr(
+    UnaryExprOrTypeTrait ExprKind, Expr *E, QualType resultType,
+    SourceLocation op, SourceLocation rp)
+    : Expr(UnaryExprOrTypeTraitExprClass, resultType, VK_RValue, OK_Ordinary,
+           false, // Never type-dependent (C++ [temp.dep.expr]p3).
+           // Value-dependent if the argument is type-dependent.
+           E->isTypeDependent(), E->isInstantiationDependent(),
+           E->containsUnexpandedParameterPack()),
+      OpLoc(op), RParenLoc(rp) {
+  UnaryExprOrTypeTraitExprBits.Kind = ExprKind;
+  UnaryExprOrTypeTraitExprBits.IsType = false;
+  Argument.Ex = E;
+
+  // Check to see if we are in the situation where alignof(decl) should be
+  // dependent because decl's alignment is dependent.
+  if (ExprKind == UETT_AlignOf) {
+    if (!isValueDependent() || !isInstantiationDependent()) {
+      E = E->IgnoreParens();
+
+      const ValueDecl *D = nullptr;
+      if (const auto *DRE = dyn_cast<DeclRefExpr>(E))
+        D = DRE->getDecl();
+      else if (const auto *ME = dyn_cast<MemberExpr>(E))
+        D = ME->getMemberDecl();
+
+      if (D) {
+        for (const auto *I : D->specific_attrs<AlignedAttr>()) {
+          if (I->isAlignmentDependent()) {
+            setValueDependent(true);
+            setInstantiationDependent(true);
+            break;
+          }
+        }
+      }
+    }
+  }
+}
+
+MemberExpr *MemberExpr::Create(
+    const ASTContext &C, Expr *base, bool isarrow, SourceLocation OperatorLoc,
+    NestedNameSpecifierLoc QualifierLoc, SourceLocation TemplateKWLoc,
+    ValueDecl *memberdecl, DeclAccessPair founddecl,
+    DeclarationNameInfo nameinfo, const TemplateArgumentListInfo *targs,
+    QualType ty, ExprValueKind vk, ExprObjectKind ok) {
   std::size_t Size = sizeof(MemberExpr);
 
   bool hasQualOrFound = (QualifierLoc ||
@@ -1384,8 +1396,8 @@ MemberExpr *MemberExpr::Create(const ASTContext &C, Expr *base, bool isarrow,
     Size += ASTTemplateKWAndArgsInfo::sizeFor(0);
 
   void *Mem = C.Allocate(Size, llvm::alignOf<MemberExpr>());
-  MemberExpr *E = new (Mem) MemberExpr(base, isarrow, memberdecl, nameinfo,
-                                       ty, vk, ok);
+  MemberExpr *E = new (Mem)
+      MemberExpr(base, isarrow, OperatorLoc, memberdecl, nameinfo, ty, vk, ok);
 
   if (hasQualOrFound) {
     // FIXME: Wrong. We should be looking at the member declaration we found.
@@ -2132,8 +2144,8 @@ bool Expr::isUnusedResultAWarning(const Expr *&WarnE, SourceLocation &Loc,
     case OO_Greater:
     case OO_GreaterEqual:
     case OO_LessEqual:
-      if (Op->getCallReturnType()->isReferenceType() ||
-          Op->getCallReturnType()->isVoidType())
+      if (Op->getCallReturnType(Ctx)->isReferenceType() ||
+          Op->getCallReturnType(Ctx)->isVoidType())
         break;
       WarnE = this;
       Loc = Op->getOperatorLoc();
@@ -2149,12 +2161,16 @@ bool Expr::isUnusedResultAWarning(const Expr *&WarnE, SourceLocation &Loc,
     // If this is a direct call, get the callee.
     const CallExpr *CE = cast<CallExpr>(this);
     if (const Decl *FD = CE->getCalleeDecl()) {
+      const FunctionDecl *Func = dyn_cast<FunctionDecl>(FD);
+      bool HasWarnUnusedResultAttr = Func ? Func->hasUnusedResultAttr()
+                                          : FD->hasAttr<WarnUnusedResultAttr>();
+
       // If the callee has attribute pure, const, or warn_unused_result, warn
       // about it. void foo() { strlen("bar"); } should warn.
       //
       // Note: If new cases are added here, DiagnoseUnusedExprResult should be
       // updated to match for QoI.
-      if (FD->hasAttr<WarnUnusedResultAttr>() ||
+      if (HasWarnUnusedResultAttr ||
           FD->hasAttr<PureAttr>() || FD->hasAttr<ConstAttr>()) {
         WarnE = this;
         Loc = CE->getCallee()->getLocStart();
@@ -2200,9 +2216,7 @@ bool Expr::isUnusedResultAWarning(const Expr *&WarnE, SourceLocation &Loc,
     }
 
     if (const ObjCMethodDecl *MD = ME->getMethodDecl())
-      if (MD->hasAttr<WarnUnusedResultAttr>() ||
-          (MD->isPropertyAccessor() && !MD->getReturnType()->isVoidType() &&
-           !ME->getReceiverType()->isObjCIdType())) {
+      if (MD->hasAttr<WarnUnusedResultAttr>()) {
         WarnE = this;
         Loc = getExprLoc();
         return true;
@@ -2387,7 +2401,7 @@ QualType Expr::findBoundMemberType(const Expr *expr) {
     return type;
   }
 
-  assert(isa<UnresolvedMemberExpr>(expr));
+  assert(isa<UnresolvedMemberExpr>(expr) || isa<CXXPseudoDestructorExpr>(expr));
   return QualType();
 }
 
@@ -2932,11 +2946,19 @@ bool Expr::HasSideEffects(const ASTContext &Ctx,
   case CXXOperatorCallExprClass:
   case CXXMemberCallExprClass:
   case CUDAKernelCallExprClass:
+  case UserDefinedLiteralClass: {
+    // We don't know a call definitely has side effects, except for calls
+    // to pure/const functions that definitely don't.
+    // If the call itself is considered side-effect free, check the operands.
+    const Decl *FD = cast<CallExpr>(this)->getCalleeDecl();
+    bool IsPure = FD && (FD->hasAttr<ConstAttr>() || FD->hasAttr<PureAttr>());
+    if (IsPure || !IncludePossibleEffects)
+      break;
+    return true;
+  }
+
   case BlockExprClass:
   case CXXBindTemporaryExprClass:
-  case UserDefinedLiteralClass:
-    // We don't know a call definitely has side effects, but we can check the
-    // call's operands.
     if (!IncludePossibleEffects)
       break;
     return true;
diff --git a/lib/AST/ExprCXX.cpp b/lib/AST/ExprCXX.cpp
index 93361666183b..d6f2ce63a0a5 100644
--- a/lib/AST/ExprCXX.cpp
+++ b/lib/AST/ExprCXX.cpp
@@ -208,8 +208,9 @@ void CXXNewExpr::AllocateArgsArray(const ASTContext &C, bool isArray,
 }
 
 bool CXXNewExpr::shouldNullCheckAllocation(const ASTContext &Ctx) const {
-  return getOperatorNew()->getType()->
-    castAs<FunctionProtoType>()->isNothrow(Ctx);
+  return getOperatorNew()->getType()->castAs<FunctionProtoType>()->isNothrow(
+             Ctx) &&
+         !getOperatorNew()->isReservedGlobalPlacementOperator();
 }
 
 // CXXDeleteExpr
@@ -237,10 +238,7 @@ CXXPseudoDestructorExpr::CXXPseudoDestructorExpr(const ASTContext &Context,
                 SourceLocation ColonColonLoc, SourceLocation TildeLoc, 
                 PseudoDestructorTypeStorage DestroyedType)
   : Expr(CXXPseudoDestructorExprClass,
-         Context.getPointerType(Context.getFunctionType(
-             Context.VoidTy, None,
-             FunctionProtoType::ExtProtoInfo(
-                 Context.getDefaultCallingConvention(false, true)))),
+         Context.BoundMemberTy,
          VK_RValue, OK_Ordinary,
          /*isTypeDependent=*/(Base->isTypeDependent() ||
            (DestroyedType.getTypeSourceInfo() &&
@@ -359,8 +357,7 @@ OverloadExpr::OverloadExpr(StmtClass K, const ASTContext &C,
     Results = static_cast<DeclAccessPair *>(
                                 C.Allocate(sizeof(DeclAccessPair) * NumResults, 
                                            llvm::alignOf<DeclAccessPair>()));
-    memcpy(Results, &*Begin.getIterator(), 
-           NumResults * sizeof(DeclAccessPair));
+    memcpy(Results, Begin.I, NumResults * sizeof(DeclAccessPair));
   }
 
   // If we have explicit template arguments, check for dependent
@@ -401,8 +398,7 @@ void OverloadExpr::initializeResults(const ASTContext &C,
                                C.Allocate(sizeof(DeclAccessPair) * NumResults,
  
                                           llvm::alignOf<DeclAccessPair>()));
-     memcpy(Results, &*Begin.getIterator(), 
-            NumResults * sizeof(DeclAccessPair));
+     memcpy(Results, Begin.I, NumResults * sizeof(DeclAccessPair));
   }
 }
 
@@ -1031,6 +1027,11 @@ LambdaExpr *LambdaExpr::CreateDeserialized(const ASTContext &C,
   return new (Mem) LambdaExpr(EmptyShell(), NumCaptures, NumArrayIndexVars > 0);
 }
 
+bool LambdaExpr::isInitCapture(const LambdaCapture *C) const {
+  return (C->capturesVariable() && C->getCapturedVar()->isInitCapture() &&
+          (getCallOperator() == C->getCapturedVar()->getDeclContext()));
+}
+
 LambdaExpr::capture_iterator LambdaExpr::capture_begin() const {
   return getLambdaClass()->getLambdaData().Captures;
 }
diff --git a/lib/AST/ExprClassification.cpp b/lib/AST/ExprClassification.cpp
index 933ea97fa2ba..5b320c2694ab 100644
--- a/lib/AST/ExprClassification.cpp
+++ b/lib/AST/ExprClassification.cpp
@@ -283,7 +283,7 @@ static Cl::Kinds ClassifyInternal(ASTContext &Ctx, const Expr *E) {
   case Expr::CXXMemberCallExprClass:
   case Expr::UserDefinedLiteralClass:
   case Expr::CUDAKernelCallExprClass:
-    return ClassifyUnnamed(Ctx, cast<CallExpr>(E)->getCallReturnType());
+    return ClassifyUnnamed(Ctx, cast<CallExpr>(E)->getCallReturnType(Ctx));
 
     // __builtin_choose_expr is equivalent to the chosen expression.
   case Expr::ChooseExprClass:
@@ -418,9 +418,10 @@ static Cl::Kinds ClassifyDecl(ASTContext &Ctx, const Decl *D) {
     islvalue = NTTParm->getType()->isReferenceType();
   else
     islvalue = isa<VarDecl>(D) || isa<FieldDecl>(D) ||
-	  isa<IndirectFieldDecl>(D) ||
-      (Ctx.getLangOpts().CPlusPlus &&
-        (isa<FunctionDecl>(D) || isa<FunctionTemplateDecl>(D)));
+               isa<IndirectFieldDecl>(D) ||
+               (Ctx.getLangOpts().CPlusPlus &&
+                (isa<FunctionDecl>(D) || isa<MSPropertyDecl>(D) ||
+                 isa<FunctionTemplateDecl>(D)));
 
   return islvalue ? Cl::CL_LValue : Cl::CL_PRValue;
 }
@@ -605,7 +606,7 @@ static Cl::ModifiableType IsModifiable(ASTContext &Ctx, const Expr *E,
   if (CT.isConstQualified())
     return Cl::CM_ConstQualified;
   if (CT.getQualifiers().getAddressSpace() == LangAS::opencl_constant)
-    return Cl::CM_ConstQualified;
+    return Cl::CM_ConstAddrSpace;
 
   // Arrays are not modifiable, only their elements are.
   if (CT->isArrayType())
@@ -671,6 +672,7 @@ Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const {
     llvm_unreachable("CM_LValueCast and CL_LValue don't match");
   case Cl::CM_NoSetterProperty: return MLV_NoSetterProperty;
   case Cl::CM_ConstQualified: return MLV_ConstQualified;
+  case Cl::CM_ConstAddrSpace: return MLV_ConstAddrSpace;
   case Cl::CM_ArrayType: return MLV_ArrayType;
   case Cl::CM_IncompleteType: return MLV_IncompleteType;
   }
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index 3d7f2dca7a2f..d1ec7aea1d2a 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -1406,7 +1406,7 @@ static bool CheckConstantExpression(EvalInfo &Info, SourceLocation DiagLoc,
   return true;
 }
 
-const ValueDecl *GetLValueBaseDecl(const LValue &LVal) {
+static const ValueDecl *GetLValueBaseDecl(const LValue &LVal) {
   return LVal.Base.dyn_cast<const ValueDecl*>();
 }
 
@@ -2173,7 +2173,7 @@ struct CompleteObject {
     assert(Value && "missing value for complete object");
   }
 
-  LLVM_EXPLICIT operator bool() const { return Value; }
+  explicit operator bool() const { return Value; }
 };
 
 /// Find the designated sub-object of an rvalue.
@@ -2502,8 +2502,9 @@ static bool AreElementsOfSameArray(QualType ObjType,
 }
 
 /// Find the complete object to which an LValue refers.
-CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E, AccessKinds AK,
-                                  const LValue &LVal, QualType LValType) {
+static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
+                                         AccessKinds AK, const LValue &LVal,
+                                         QualType LValType) {
   if (!LVal.Base) {
     Info.Diag(E, diag::note_constexpr_access_null) << AK;
     return CompleteObject();
@@ -3726,8 +3727,9 @@ static bool HandleFunctionCall(SourceLocation CallLoc,
   // Skip this for non-union classes with no fields; in that case, the defaulted
   // copy/move does not actually read the object.
   const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Callee);
-  if (MD && MD->isDefaulted() && MD->isTrivial() &&
-      (MD->getParent()->isUnion() || hasFields(MD->getParent()))) {
+  if (MD && MD->isDefaulted() &&
+      (MD->getParent()->isUnion() ||
+       (MD->isTrivial() && hasFields(MD->getParent())))) {
     assert(This &&
            (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()));
     LValue RHS;
@@ -3791,11 +3793,9 @@ static bool HandleConstructorCall(SourceLocation CallLoc, const LValue &This,
   // Skip this for empty non-union classes; we should not perform an
   // lvalue-to-rvalue conversion on them because their copy constructor does not
   // actually read them.
-  if (Definition->isDefaulted() &&
-      ((Definition->isCopyConstructor() && Definition->isTrivial()) ||
-       (Definition->isMoveConstructor() && Definition->isTrivial())) &&
+  if (Definition->isDefaulted() && Definition->isCopyOrMoveConstructor() &&
       (Definition->getParent()->isUnion() ||
-       hasFields(Definition->getParent()))) {
+       (Definition->isTrivial() && hasFields(Definition->getParent())))) {
     LValue RHS;
     RHS.setFrom(Info.Ctx, ArgValues[0]);
     return handleLValueToRValueConversion(Info, Args[0], Args[0]->getType(),
@@ -6834,7 +6834,7 @@ void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
 }
 
 bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
-  if (E->isAssignmentOp())
+  if (!Info.keepEvaluatingAfterFailure() && E->isAssignmentOp())
     return Error(E);
 
   if (DataRecursiveIntBinOpEvaluator::shouldEnqueue(E))
@@ -6846,7 +6846,11 @@ bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
   if (LHSTy->isAnyComplexType() || RHSTy->isAnyComplexType()) {
     ComplexValue LHS, RHS;
     bool LHSOK;
-    if (E->getLHS()->getType()->isRealFloatingType()) {
+    if (E->isAssignmentOp()) {
+      LValue LV;
+      EvaluateLValue(E->getLHS(), LV, Info);
+      LHSOK = false;
+    } else if (LHSTy->isRealFloatingType()) {
       LHSOK = EvaluateFloat(E->getLHS(), LHS.FloatReal, Info);
       if (LHSOK) {
         LHS.makeComplexFloat();
@@ -7586,10 +7590,23 @@ static bool TryEvaluateBuiltinNaN(const ASTContext &Context,
   else if (S->getString().getAsInteger(0, fill))
     return false;
 
-  if (SNaN)
-    Result = llvm::APFloat::getSNaN(Sem, false, &fill);
-  else
-    Result = llvm::APFloat::getQNaN(Sem, false, &fill);
+  if (Context.getTargetInfo().isNan2008()) {
+    if (SNaN)
+      Result = llvm::APFloat::getSNaN(Sem, false, &fill);
+    else
+      Result = llvm::APFloat::getQNaN(Sem, false, &fill);
+  } else {
+    // Prior to IEEE 754-2008, architectures were allowed to choose whether
+    // the first bit of their significand was set for qNaN or sNaN. MIPS chose
+    // a different encoding to what became a standard in 2008, and for pre-
+    // 2008 revisions, MIPS interpreted sNaN-2008 as qNan and qNaN-2008 as
+    // sNaN. This is now known as "legacy NaN" encoding.
+    if (SNaN)
+      Result = llvm::APFloat::getQNaN(Sem, false, &fill);
+    else
+      Result = llvm::APFloat::getSNaN(Sem, false, &fill);
+  }
+
   return true;
 }
 
diff --git a/lib/AST/ExternalASTSource.cpp b/lib/AST/ExternalASTSource.cpp
index 88941075dd06..730842a28f6a 100644
--- a/lib/AST/ExternalASTSource.cpp
+++ b/lib/AST/ExternalASTSource.cpp
@@ -66,6 +66,11 @@ Stmt *ExternalASTSource::GetExternalDeclStmt(uint64_t Offset) {
   return nullptr;
 }
 
+CXXCtorInitializer **
+ExternalASTSource::GetExternalCXXCtorInitializers(uint64_t Offset) {
+  return nullptr;
+}
+
 CXXBaseSpecifier *
 ExternalASTSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
   return nullptr;
diff --git a/lib/AST/InheritViz.cpp b/lib/AST/InheritViz.cpp
index eb3020c5f518..0b82da133fa7 100644
--- a/lib/AST/InheritViz.cpp
+++ b/lib/AST/InheritViz.cpp
@@ -22,11 +22,9 @@
 #include "llvm/Support/raw_ostream.h"
 #include <map>
 #include <set>
+using namespace clang;
 
-using namespace llvm;
-
-namespace clang {
-
+namespace {
 /// InheritanceHierarchyWriter - Helper class that writes out a
 /// GraphViz file that diagrams the inheritance hierarchy starting at
 /// a given C++ class type. Note that we do not use LLVM's
@@ -44,7 +42,8 @@ public:
     : Context(Context), Out(Out) { }
 
   void WriteGraph(QualType Type) {
-    Out << "digraph \"" << DOT::EscapeString(Type.getAsString()) << "\" {\n";
+    Out << "digraph \"" << llvm::DOT::EscapeString(Type.getAsString())
+        << "\" {\n";
     WriteNode(Type, false);
     Out << "}\n";
   }
@@ -59,6 +58,7 @@ protected:
   /// (only) virtual base.
   raw_ostream& WriteNodeReference(QualType Type, bool FromVirtual);
 };
+} // namespace
 
 void InheritanceHierarchyWriter::WriteNode(QualType Type, bool FromVirtual) {
   QualType CanonType = Context.getCanonicalType(Type);
@@ -78,7 +78,7 @@ void InheritanceHierarchyWriter::WriteNode(QualType Type, bool FromVirtual) {
 
   // Give the node a label based on the name of the class.
   std::string TypeName = Type.getAsString();
-  Out << " [ shape=\"box\", label=\"" << DOT::EscapeString(TypeName);
+  Out << " [ shape=\"box\", label=\"" << llvm::DOT::EscapeString(TypeName);
 
   // If the name of the class was a typedef or something different
   // from the "real" class name, show the real class name in
@@ -139,9 +139,8 @@ void CXXRecordDecl::viewInheritance(ASTContext& Context) const {
 
   int FD;
   SmallString<128> Filename;
-  std::error_code EC =
-      sys::fs::createTemporaryFile(Self.getAsString(), "dot", FD, Filename);
-  if (EC) {
+  if (std::error_code EC = llvm::sys::fs::createTemporaryFile(
+          Self.getAsString(), "dot", FD, Filename)) {
     llvm::errs() << "Error: " << EC.message() << "\n";
     return;
   }
@@ -159,5 +158,3 @@ void CXXRecordDecl::viewInheritance(ASTContext& Context) const {
   // Display the graph
   DisplayGraph(Filename);
 }
-
-}
diff --git a/lib/AST/ItaniumCXXABI.cpp b/lib/AST/ItaniumCXXABI.cpp
index 378121c8e5b9..7503cbfc9805 100644
--- a/lib/AST/ItaniumCXXABI.cpp
+++ b/lib/AST/ItaniumCXXABI.cpp
@@ -106,7 +106,7 @@ public:
     TargetInfo::IntType PtrDiff = Target.getPtrDiffType(0);
     uint64_t Width = Target.getTypeWidth(PtrDiff);
     unsigned Align = Target.getTypeAlign(PtrDiff);
-    if (MPT->getPointeeType()->isFunctionType())
+    if (MPT->isMemberFunctionPointer())
       Width = 2 * Width;
     return std::make_pair(Width, Align);
   }
@@ -133,6 +133,22 @@ public:
     return Layout.getNonVirtualSize() == PointerSize;
   }
 
+  const CXXConstructorDecl *
+  getCopyConstructorForExceptionObject(CXXRecordDecl *RD) override {
+    return nullptr;
+  }
+
+  void addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
+                                            CXXConstructorDecl *CD) override {}
+
+  void addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                       unsigned ParmIdx, Expr *DAE) override {}
+
+  Expr *getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                        unsigned ParmIdx) override {
+    return nullptr;
+  }
+
   MangleNumberingContext *createMangleNumberingContext() const override {
     return new ItaniumNumberingContext();
   }
diff --git a/lib/AST/ItaniumMangle.cpp b/lib/AST/ItaniumMangle.cpp
index 156ad646fa6d..d07efaee7bba 100644
--- a/lib/AST/ItaniumMangle.cpp
+++ b/lib/AST/ItaniumMangle.cpp
@@ -42,8 +42,8 @@ using namespace clang;
 
 namespace {
 
-/// \brief Retrieve the declaration context that should be used when mangling 
-/// the given declaration.
+/// Retrieve the declaration context that should be used when mangling the given
+/// declaration.
 static const DeclContext *getEffectiveDeclContext(const Decl *D) {
   // The ABI assumes that lambda closure types that occur within 
   // default arguments live in the context of the function. However, due to
@@ -69,6 +69,14 @@ static const DeclContext *getEffectiveDeclContext(const Decl *D) {
   if (const CapturedDecl *CD = dyn_cast<CapturedDecl>(DC))
     return getEffectiveDeclContext(CD);
 
+  if (const auto *VD = dyn_cast<VarDecl>(D))
+    if (VD->isExternC())
+      return VD->getASTContext().getTranslationUnitDecl();
+
+  if (const auto *FD = dyn_cast<FunctionDecl>(D))
+    if (FD->isExternC())
+      return FD->getASTContext().getTranslationUnitDecl();
+
   return DC;
 }
 
@@ -156,12 +164,18 @@ public:
   void mangleDynamicInitializer(const VarDecl *D, raw_ostream &Out) override;
   void mangleDynamicAtExitDestructor(const VarDecl *D,
                                      raw_ostream &Out) override;
+  void mangleSEHFilterExpression(const NamedDecl *EnclosingDecl,
+                                 raw_ostream &Out) override;
+  void mangleSEHFinallyBlock(const NamedDecl *EnclosingDecl,
+                             raw_ostream &Out) override;
   void mangleItaniumThreadLocalInit(const VarDecl *D, raw_ostream &) override;
   void mangleItaniumThreadLocalWrapper(const VarDecl *D,
                                        raw_ostream &) override;
 
   void mangleStringLiteral(const StringLiteral *, raw_ostream &) override;
 
+  void mangleCXXVTableBitSet(const CXXRecordDecl *RD, raw_ostream &) override;
+
   bool getNextDiscriminator(const NamedDecl *ND, unsigned &disc) {
     // Lambda closure types are already numbered.
     if (isLambda(ND))
@@ -196,7 +210,7 @@ public:
   /// @}
 };
 
-/// CXXNameMangler - Manage the mangling of a single name.
+/// Manage the mangling of a single name.
 class CXXNameMangler {
   ItaniumMangleContextImpl &Context;
   raw_ostream &Out;
@@ -207,7 +221,7 @@ class CXXNameMangler {
   const NamedDecl *Structor;
   unsigned StructorType;
 
-  /// SeqID - The next subsitution sequence number.
+  /// The next substitution sequence number.
   unsigned SeqID;
 
   class FunctionTypeDepthState {
@@ -284,7 +298,7 @@ public:
 #endif
   raw_ostream &getStream() { return Out; }
 
-  void mangle(const NamedDecl *D, StringRef Prefix = "_Z");
+  void mangle(const NamedDecl *D);
   void mangleCallOffset(int64_t NonVirtual, int64_t Virtual);
   void mangleNumber(const llvm::APSInt &I);
   void mangleNumber(int64_t Number);
@@ -317,10 +331,8 @@ private:
   void addSubstitution(uintptr_t Ptr);
 
   void mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
-                              NamedDecl *firstQualifierLookup,
                               bool recursive = false);
   void mangleUnresolvedName(NestedNameSpecifier *qualifier,
-                            NamedDecl *firstQualifierLookup,
                             DeclarationName name,
                             unsigned KnownArity = UnknownArity);
 
@@ -350,6 +362,9 @@ private:
   void manglePrefix(QualType type);
   void mangleTemplatePrefix(const TemplateDecl *ND, bool NoFunction=false);
   void mangleTemplatePrefix(TemplateName Template);
+  bool mangleUnresolvedTypeOrSimpleId(QualType DestroyedType,
+                                      StringRef Prefix = "");
+  void mangleOperatorName(DeclarationName Name, unsigned Arity);
   void mangleOperatorName(OverloadedOperatorKind OO, unsigned Arity);
   void mangleQualifiers(Qualifiers Quals);
   void mangleRefQualifier(RefQualifierKind RefQualifier);
@@ -370,12 +385,14 @@ private:
   void mangleAArch64NeonVectorType(const VectorType *T);
 
   void mangleIntegerLiteral(QualType T, const llvm::APSInt &Value);
+  void mangleMemberExprBase(const Expr *base, bool isArrow);
   void mangleMemberExpr(const Expr *base, bool isArrow,
                         NestedNameSpecifier *qualifier,
                         NamedDecl *firstQualifierLookup,
                         DeclarationName name,
                         unsigned knownArity);
   void mangleCastExpression(const Expr *E, StringRef CastEncoding);
+  void mangleInitListElements(const InitListExpr *InitList);
   void mangleExpression(const Expr *E, unsigned Arity = UnknownArity);
   void mangleCXXCtorType(CXXCtorType T);
   void mangleCXXDtorType(CXXDtorType T);
@@ -439,11 +456,11 @@ bool ItaniumMangleContextImpl::shouldMangleCXXName(const NamedDecl *D) {
   return true;
 }
 
-void CXXNameMangler::mangle(const NamedDecl *D, StringRef Prefix) {
+void CXXNameMangler::mangle(const NamedDecl *D) {
   // <mangled-name> ::= _Z <encoding>
   //            ::= <data name>
   //            ::= <special-name>
-  Out << Prefix;
+  Out << "_Z";
   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
     mangleFunctionEncoding(FD);
   else if (const VarDecl *VD = dyn_cast<VarDecl>(D))
@@ -519,7 +536,7 @@ static const DeclContext *IgnoreLinkageSpecDecls(const DeclContext *DC) {
   return DC;
 }
 
-/// isStd - Return whether a given namespace is the 'std' namespace.
+/// Return whether a given namespace is the 'std' namespace.
 static bool isStd(const NamespaceDecl *NS) {
   if (!IgnoreLinkageSpecDecls(getEffectiveParentContext(NS))
                                 ->isTranslationUnit())
@@ -748,8 +765,7 @@ void CXXNameMangler::mangleCallOffset(int64_t NonVirtual, int64_t Virtual) {
 }
 
 void CXXNameMangler::manglePrefix(QualType type) {
-  if (const TemplateSpecializationType *TST =
-        type->getAs<TemplateSpecializationType>()) {
+  if (const auto *TST = type->getAs<TemplateSpecializationType>()) {
     if (!mangleSubstitution(QualType(TST, 0))) {
       mangleTemplatePrefix(TST->getTemplateName());
         
@@ -759,17 +775,19 @@ void CXXNameMangler::manglePrefix(QualType type) {
       mangleTemplateArgs(TST->getArgs(), TST->getNumArgs());
       addSubstitution(QualType(TST, 0));
     }
-  } else if (const DependentTemplateSpecializationType *DTST
-               = type->getAs<DependentTemplateSpecializationType>()) {
-    TemplateName Template
-      = getASTContext().getDependentTemplateName(DTST->getQualifier(), 
-                                                 DTST->getIdentifier());
-    mangleTemplatePrefix(Template);
+  } else if (const auto *DTST =
+                 type->getAs<DependentTemplateSpecializationType>()) {
+    if (!mangleSubstitution(QualType(DTST, 0))) {
+      TemplateName Template = getASTContext().getDependentTemplateName(
+          DTST->getQualifier(), DTST->getIdentifier());
+      mangleTemplatePrefix(Template);
 
-    // FIXME: GCC does not appear to mangle the template arguments when
-    // the template in question is a dependent template name. Should we
-    // emulate that badness?
-    mangleTemplateArgs(DTST->getArgs(), DTST->getNumArgs());
+      // FIXME: GCC does not appear to mangle the template arguments when
+      // the template in question is a dependent template name. Should we
+      // emulate that badness?
+      mangleTemplateArgs(DTST->getArgs(), DTST->getNumArgs());
+      addSubstitution(QualType(DTST, 0));
+    }
   } else {
     // We use the QualType mangle type variant here because it handles
     // substitutions.
@@ -779,12 +797,9 @@ void CXXNameMangler::manglePrefix(QualType type) {
 
 /// Mangle everything prior to the base-unresolved-name in an unresolved-name.
 ///
-/// \param firstQualifierLookup - the entity found by unqualified lookup
-///   for the first name in the qualifier, if this is for a member expression
 /// \param recursive - true if this is being called recursively,
 ///   i.e. if there is more prefix "to the right".
 void CXXNameMangler::mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
-                                            NamedDecl *firstQualifierLookup,
                                             bool recursive) {
 
   // x, ::x
@@ -817,7 +832,7 @@ void CXXNameMangler::mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
 
   case NestedNameSpecifier::Namespace:
     if (qualifier->getPrefix())
-      mangleUnresolvedPrefix(qualifier->getPrefix(), firstQualifierLookup,
+      mangleUnresolvedPrefix(qualifier->getPrefix(),
                              /*recursive*/ true);
     else
       Out << "sr";
@@ -825,7 +840,7 @@ void CXXNameMangler::mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
     break;
   case NestedNameSpecifier::NamespaceAlias:
     if (qualifier->getPrefix())
-      mangleUnresolvedPrefix(qualifier->getPrefix(), firstQualifierLookup,
+      mangleUnresolvedPrefix(qualifier->getPrefix(),
                              /*recursive*/ true);
     else
       Out << "sr";
@@ -842,193 +857,26 @@ void CXXNameMangler::mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
     //   - a template template parameter with arguments
     // In all of these cases, we should have no prefix.
     if (qualifier->getPrefix()) {
-      mangleUnresolvedPrefix(qualifier->getPrefix(), firstQualifierLookup,
+      mangleUnresolvedPrefix(qualifier->getPrefix(),
                              /*recursive*/ true);
     } else {
       // Otherwise, all the cases want this.
       Out << "sr";
     }
 
-    // Only certain other types are valid as prefixes;  enumerate them.
-    switch (type->getTypeClass()) {
-    case Type::Builtin:
-    case Type::Complex:
-    case Type::Adjusted:
-    case Type::Decayed:
-    case Type::Pointer:
-    case Type::BlockPointer:
-    case Type::LValueReference:
-    case Type::RValueReference:
-    case Type::MemberPointer:
-    case Type::ConstantArray:
-    case Type::IncompleteArray:
-    case Type::VariableArray:
-    case Type::DependentSizedArray:
-    case Type::DependentSizedExtVector:
-    case Type::Vector:
-    case Type::ExtVector:
-    case Type::FunctionProto:
-    case Type::FunctionNoProto:
-    case Type::Enum:
-    case Type::Paren:
-    case Type::Elaborated:
-    case Type::Attributed:
-    case Type::Auto:
-    case Type::PackExpansion:
-    case Type::ObjCObject:
-    case Type::ObjCInterface:
-    case Type::ObjCObjectPointer:
-    case Type::Atomic:
-      llvm_unreachable("type is illegal as a nested name specifier");
-
-    case Type::SubstTemplateTypeParmPack:
-      // FIXME: not clear how to mangle this!
-      // template <class T...> class A {
-      //   template <class U...> void foo(decltype(T::foo(U())) x...);
-      // };
-      Out << "_SUBSTPACK_";
-      break;
-
-    // <unresolved-type> ::= <template-param>
-    //                   ::= <decltype>
-    //                   ::= <template-template-param> <template-args>
-    // (this last is not official yet)
-    case Type::TypeOfExpr:
-    case Type::TypeOf:
-    case Type::Decltype:
-    case Type::TemplateTypeParm:
-    case Type::UnaryTransform:
-    case Type::SubstTemplateTypeParm:
-    unresolvedType:
-      assert(!qualifier->getPrefix());
-
-      // We only get here recursively if we're followed by identifiers.
-      if (recursive) Out << 'N';
-
-      // This seems to do everything we want.  It's not really
-      // sanctioned for a substituted template parameter, though.
-      mangleType(QualType(type, 0));
-
-      // We never want to print 'E' directly after an unresolved-type,
-      // so we return directly.
+    if (mangleUnresolvedTypeOrSimpleId(QualType(type, 0), recursive ? "N" : ""))
       return;
 
-    case Type::Typedef:
-      mangleSourceName(cast<TypedefType>(type)->getDecl()->getIdentifier());
-      break;
-
-    case Type::UnresolvedUsing:
-      mangleSourceName(cast<UnresolvedUsingType>(type)->getDecl()
-                         ->getIdentifier());
-      break;
-
-    case Type::Record:
-      mangleSourceName(cast<RecordType>(type)->getDecl()->getIdentifier());
-      break;
-
-    case Type::TemplateSpecialization: {
-      const TemplateSpecializationType *tst
-        = cast<TemplateSpecializationType>(type);
-      TemplateName name = tst->getTemplateName();
-      switch (name.getKind()) {
-      case TemplateName::Template:
-      case TemplateName::QualifiedTemplate: {
-        TemplateDecl *temp = name.getAsTemplateDecl();
-
-        // If the base is a template template parameter, this is an
-        // unresolved type.
-        assert(temp && "no template for template specialization type");
-        if (isa<TemplateTemplateParmDecl>(temp)) goto unresolvedType;
-
-        mangleSourceName(temp->getIdentifier());
-        break;
-      }
-
-      case TemplateName::OverloadedTemplate:
-      case TemplateName::DependentTemplate:
-        llvm_unreachable("invalid base for a template specialization type");
-
-      case TemplateName::SubstTemplateTemplateParm: {
-        SubstTemplateTemplateParmStorage *subst
-          = name.getAsSubstTemplateTemplateParm();
-        mangleExistingSubstitution(subst->getReplacement());
-        break;
-      }
-
-      case TemplateName::SubstTemplateTemplateParmPack: {
-        // FIXME: not clear how to mangle this!
-        // template <template <class U> class T...> class A {
-        //   template <class U...> void foo(decltype(T<U>::foo) x...);
-        // };
-        Out << "_SUBSTPACK_";
-        break;
-      }
-      }
-
-      mangleTemplateArgs(tst->getArgs(), tst->getNumArgs());
-      break;
-    }
-
-    case Type::InjectedClassName:
-      mangleSourceName(cast<InjectedClassNameType>(type)->getDecl()
-                         ->getIdentifier());
-      break;
-
-    case Type::DependentName:
-      mangleSourceName(cast<DependentNameType>(type)->getIdentifier());
-      break;
-
-    case Type::DependentTemplateSpecialization: {
-      const DependentTemplateSpecializationType *tst
-        = cast<DependentTemplateSpecializationType>(type);
-      mangleSourceName(tst->getIdentifier());
-      mangleTemplateArgs(tst->getArgs(), tst->getNumArgs());
-      break;
-    }
-    }
     break;
   }
 
   case NestedNameSpecifier::Identifier:
     // Member expressions can have these without prefixes.
-    if (qualifier->getPrefix()) {
-      mangleUnresolvedPrefix(qualifier->getPrefix(), firstQualifierLookup,
+    if (qualifier->getPrefix())
+      mangleUnresolvedPrefix(qualifier->getPrefix(),
                              /*recursive*/ true);
-    } else if (firstQualifierLookup) {
-
-      // Try to make a proper qualifier out of the lookup result, and
-      // then just recurse on that.
-      NestedNameSpecifier *newQualifier;
-      if (TypeDecl *typeDecl = dyn_cast<TypeDecl>(firstQualifierLookup)) {
-        QualType type = getASTContext().getTypeDeclType(typeDecl);
-
-        // Pretend we had a different nested name specifier.
-        newQualifier = NestedNameSpecifier::Create(getASTContext(),
-                                                   /*prefix*/ nullptr,
-                                                   /*template*/ false,
-                                                   type.getTypePtr());
-      } else if (NamespaceDecl *nspace =
-                   dyn_cast<NamespaceDecl>(firstQualifierLookup)) {
-        newQualifier = NestedNameSpecifier::Create(getASTContext(),
-                                                   /*prefix*/ nullptr,
-                                                   nspace);
-      } else if (NamespaceAliasDecl *alias =
-                   dyn_cast<NamespaceAliasDecl>(firstQualifierLookup)) {
-        newQualifier = NestedNameSpecifier::Create(getASTContext(),
-                                                   /*prefix*/ nullptr,
-                                                   alias);
-      } else {
-        // No sensible mangling to do here.
-        newQualifier = nullptr;
-      }
-
-      if (newQualifier)
-        return mangleUnresolvedPrefix(newQualifier, /*lookup*/ nullptr,
-                                      recursive);
-
-    } else {
+    else
       Out << "sr";
-    }
 
     mangleSourceName(qualifier->getAsIdentifier());
     break;
@@ -1043,16 +891,41 @@ void CXXNameMangler::mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
 /// Mangle an unresolved-name, which is generally used for names which
 /// weren't resolved to specific entities.
 void CXXNameMangler::mangleUnresolvedName(NestedNameSpecifier *qualifier,
-                                          NamedDecl *firstQualifierLookup,
                                           DeclarationName name,
                                           unsigned knownArity) {
-  if (qualifier) mangleUnresolvedPrefix(qualifier, firstQualifierLookup);
-  mangleUnqualifiedName(nullptr, name, knownArity);
+  if (qualifier) mangleUnresolvedPrefix(qualifier);
+  switch (name.getNameKind()) {
+    // <base-unresolved-name> ::= <simple-id>
+    case DeclarationName::Identifier:
+      mangleSourceName(name.getAsIdentifierInfo());
+      break;
+    // <base-unresolved-name> ::= dn <destructor-name>
+    case DeclarationName::CXXDestructorName:
+      Out << "dn";
+      mangleUnresolvedTypeOrSimpleId(name.getCXXNameType());
+      break;
+    // <base-unresolved-name> ::= on <operator-name>
+    case DeclarationName::CXXConversionFunctionName:
+    case DeclarationName::CXXLiteralOperatorName:
+    case DeclarationName::CXXOperatorName:
+      Out << "on";
+      mangleOperatorName(name, knownArity);
+      break;
+    case DeclarationName::CXXConstructorName:
+      llvm_unreachable("Can't mangle a constructor name!");
+    case DeclarationName::CXXUsingDirective:
+      llvm_unreachable("Can't mangle a using directive name!");
+    case DeclarationName::ObjCMultiArgSelector:
+    case DeclarationName::ObjCOneArgSelector:
+    case DeclarationName::ObjCZeroArgSelector:
+      llvm_unreachable("Can't mangle Objective-C selector names here!");
+  }
 }
 
 void CXXNameMangler::mangleUnqualifiedName(const NamedDecl *ND,
                                            DeclarationName Name,
                                            unsigned KnownArity) {
+  unsigned Arity = KnownArity;
   //  <unqualified-name> ::= <operator-name>
   //                     ::= <ctor-dtor-name>
   //                     ::= <source-name>
@@ -1163,7 +1036,7 @@ void CXXNameMangler::mangleUnqualifiedName(const NamedDecl *ND,
     Str += llvm::utostr(AnonStructId);
 
     Out << Str.size();
-    Out << Str.str();
+    Out << Str;
     break;
   }
 
@@ -1194,33 +1067,19 @@ void CXXNameMangler::mangleUnqualifiedName(const NamedDecl *ND,
       mangleCXXDtorType(Dtor_Complete);
     break;
 
-  case DeclarationName::CXXConversionFunctionName:
-    // <operator-name> ::= cv <type>    # (cast)
-    Out << "cv";
-    mangleType(Name.getCXXNameType());
-    break;
-
-  case DeclarationName::CXXOperatorName: {
-    unsigned Arity;
-    if (ND) {
+  case DeclarationName::CXXOperatorName:
+    if (ND && Arity == UnknownArity) {
       Arity = cast<FunctionDecl>(ND)->getNumParams();
 
-      // If we have a C++ member function, we need to include the 'this' pointer.
-      // FIXME: This does not make sense for operators that are static, but their
-      // names stay the same regardless of the arity (operator new for instance).
-      if (isa<CXXMethodDecl>(ND))
-        Arity++;
-    } else
-      Arity = KnownArity;
-
-    mangleOperatorName(Name.getCXXOverloadedOperator(), Arity);
-    break;
-  }
-
+      // If we have a member function, we need to include the 'this' pointer.
+      if (const auto *MD = dyn_cast<CXXMethodDecl>(ND))
+        if (!MD->isStatic())
+          Arity++;
+    }
+  // FALLTHROUGH
+  case DeclarationName::CXXConversionFunctionName:
   case DeclarationName::CXXLiteralOperatorName:
-    // FIXME: This mangling is not yet official.
-    Out << "li";
-    mangleSourceName(Name.getCXXLiteralIdentifier());
+    mangleOperatorName(Name, Arity);
     break;
 
   case DeclarationName::CXXUsingDirective:
@@ -1529,7 +1388,8 @@ void CXXNameMangler::mangleTemplatePrefix(TemplateName Template) {
    
   DependentTemplateName *Dependent = Template.getAsDependentTemplateName();
   assert(Dependent && "Unknown template name kind?");
-  manglePrefix(Dependent->getQualifier());
+  if (NestedNameSpecifier *Qualifier = Dependent->getQualifier())
+    manglePrefix(Qualifier);
   mangleUnscopedTemplateName(Template);
 }
 
@@ -1591,7 +1451,7 @@ void CXXNameMangler::mangleType(TemplateName TN) {
 
     // <class-enum-type> ::= <name>
     // <name> ::= <nested-name>
-    mangleUnresolvedPrefix(Dependent->getQualifier(), nullptr);
+    mangleUnresolvedPrefix(Dependent->getQualifier());
     mangleSourceName(Dependent->getIdentifier());
     break;
   }
@@ -1620,6 +1480,181 @@ void CXXNameMangler::mangleType(TemplateName TN) {
   addSubstitution(TN);
 }
 
+bool CXXNameMangler::mangleUnresolvedTypeOrSimpleId(QualType Ty,
+                                                    StringRef Prefix) {
+  // Only certain other types are valid as prefixes;  enumerate them.
+  switch (Ty->getTypeClass()) {
+  case Type::Builtin:
+  case Type::Complex:
+  case Type::Adjusted:
+  case Type::Decayed:
+  case Type::Pointer:
+  case Type::BlockPointer:
+  case Type::LValueReference:
+  case Type::RValueReference:
+  case Type::MemberPointer:
+  case Type::ConstantArray:
+  case Type::IncompleteArray:
+  case Type::VariableArray:
+  case Type::DependentSizedArray:
+  case Type::DependentSizedExtVector:
+  case Type::Vector:
+  case Type::ExtVector:
+  case Type::FunctionProto:
+  case Type::FunctionNoProto:
+  case Type::Paren:
+  case Type::Attributed:
+  case Type::Auto:
+  case Type::PackExpansion:
+  case Type::ObjCObject:
+  case Type::ObjCInterface:
+  case Type::ObjCObjectPointer:
+  case Type::Atomic:
+    llvm_unreachable("type is illegal as a nested name specifier");
+
+  case Type::SubstTemplateTypeParmPack:
+    // FIXME: not clear how to mangle this!
+    // template <class T...> class A {
+    //   template <class U...> void foo(decltype(T::foo(U())) x...);
+    // };
+    Out << "_SUBSTPACK_";
+    break;
+
+  // <unresolved-type> ::= <template-param>
+  //                   ::= <decltype>
+  //                   ::= <template-template-param> <template-args>
+  // (this last is not official yet)
+  case Type::TypeOfExpr:
+  case Type::TypeOf:
+  case Type::Decltype:
+  case Type::TemplateTypeParm:
+  case Type::UnaryTransform:
+  case Type::SubstTemplateTypeParm:
+  unresolvedType:
+    // Some callers want a prefix before the mangled type.
+    Out << Prefix;
+
+    // This seems to do everything we want.  It's not really
+    // sanctioned for a substituted template parameter, though.
+    mangleType(Ty);
+
+    // We never want to print 'E' directly after an unresolved-type,
+    // so we return directly.
+    return true;
+
+  case Type::Typedef:
+    mangleSourceName(cast<TypedefType>(Ty)->getDecl()->getIdentifier());
+    break;
+
+  case Type::UnresolvedUsing:
+    mangleSourceName(
+        cast<UnresolvedUsingType>(Ty)->getDecl()->getIdentifier());
+    break;
+
+  case Type::Enum:
+  case Type::Record:
+    mangleSourceName(cast<TagType>(Ty)->getDecl()->getIdentifier());
+    break;
+
+  case Type::TemplateSpecialization: {
+    const TemplateSpecializationType *TST =
+        cast<TemplateSpecializationType>(Ty);
+    TemplateName TN = TST->getTemplateName();
+    switch (TN.getKind()) {
+    case TemplateName::Template:
+    case TemplateName::QualifiedTemplate: {
+      TemplateDecl *TD = TN.getAsTemplateDecl();
+
+      // If the base is a template template parameter, this is an
+      // unresolved type.
+      assert(TD && "no template for template specialization type");
+      if (isa<TemplateTemplateParmDecl>(TD))
+        goto unresolvedType;
+
+      mangleSourceName(TD->getIdentifier());
+      break;
+    }
+
+    case TemplateName::OverloadedTemplate:
+    case TemplateName::DependentTemplate:
+      llvm_unreachable("invalid base for a template specialization type");
+
+    case TemplateName::SubstTemplateTemplateParm: {
+      SubstTemplateTemplateParmStorage *subst =
+          TN.getAsSubstTemplateTemplateParm();
+      mangleExistingSubstitution(subst->getReplacement());
+      break;
+    }
+
+    case TemplateName::SubstTemplateTemplateParmPack: {
+      // FIXME: not clear how to mangle this!
+      // template <template <class U> class T...> class A {
+      //   template <class U...> void foo(decltype(T<U>::foo) x...);
+      // };
+      Out << "_SUBSTPACK_";
+      break;
+    }
+    }
+
+    mangleTemplateArgs(TST->getArgs(), TST->getNumArgs());
+    break;
+  }
+
+  case Type::InjectedClassName:
+    mangleSourceName(
+        cast<InjectedClassNameType>(Ty)->getDecl()->getIdentifier());
+    break;
+
+  case Type::DependentName:
+    mangleSourceName(cast<DependentNameType>(Ty)->getIdentifier());
+    break;
+
+  case Type::DependentTemplateSpecialization: {
+    const DependentTemplateSpecializationType *DTST =
+        cast<DependentTemplateSpecializationType>(Ty);
+    mangleSourceName(DTST->getIdentifier());
+    mangleTemplateArgs(DTST->getArgs(), DTST->getNumArgs());
+    break;
+  }
+
+  case Type::Elaborated:
+    return mangleUnresolvedTypeOrSimpleId(
+        cast<ElaboratedType>(Ty)->getNamedType(), Prefix);
+  }
+
+  return false;
+}
+
+void CXXNameMangler::mangleOperatorName(DeclarationName Name, unsigned Arity) {
+  switch (Name.getNameKind()) {
+  case DeclarationName::CXXConstructorName:
+  case DeclarationName::CXXDestructorName:
+  case DeclarationName::CXXUsingDirective:
+  case DeclarationName::Identifier:
+  case DeclarationName::ObjCMultiArgSelector:
+  case DeclarationName::ObjCOneArgSelector:
+  case DeclarationName::ObjCZeroArgSelector:
+    llvm_unreachable("Not an operator name");
+
+  case DeclarationName::CXXConversionFunctionName:
+    // <operator-name> ::= cv <type>    # (cast)
+    Out << "cv";
+    mangleType(Name.getCXXNameType());
+    break;
+
+  case DeclarationName::CXXLiteralOperatorName:
+    Out << "li";
+    mangleSourceName(Name.getCXXLiteralIdentifier());
+    return;
+
+  case DeclarationName::CXXOperatorName:
+    mangleOperatorName(Name.getCXXOverloadedOperator(), Arity);
+    break;
+  }
+}
+
+
+
 void
 CXXNameMangler::mangleOperatorName(OverloadedOperatorKind OO, unsigned Arity) {
   switch (OO) {
@@ -2276,6 +2311,7 @@ void CXXNameMangler::mangleAArch64NeonVectorType(const VectorType *T) {
       EltName = "Poly16";
       break;
     case BuiltinType::ULong:
+    case BuiltinType::ULongLong:
       EltName = "Poly64";
       break;
     default:
@@ -2519,6 +2555,29 @@ void CXXNameMangler::mangleIntegerLiteral(QualType T,
 
 }
 
+void CXXNameMangler::mangleMemberExprBase(const Expr *Base, bool IsArrow) {
+  // Ignore member expressions involving anonymous unions.
+  while (const auto *RT = Base->getType()->getAs<RecordType>()) {
+    if (!RT->getDecl()->isAnonymousStructOrUnion())
+      break;
+    const auto *ME = dyn_cast<MemberExpr>(Base);
+    if (!ME)
+      break;
+    Base = ME->getBase();
+    IsArrow = ME->isArrow();
+  }
+
+  if (Base->isImplicitCXXThis()) {
+    // Note: GCC mangles member expressions to the implicit 'this' as
+    // *this., whereas we represent them as this->. The Itanium C++ ABI
+    // does not specify anything here, so we follow GCC.
+    Out << "dtdefpT";
+  } else {
+    Out << (IsArrow ? "pt" : "dt");
+    mangleExpression(Base);
+  }
+}
+
 /// Mangles a member expression.
 void CXXNameMangler::mangleMemberExpr(const Expr *base,
                                       bool isArrow,
@@ -2528,30 +2587,9 @@ void CXXNameMangler::mangleMemberExpr(const Expr *base,
                                       unsigned arity) {
   // <expression> ::= dt <expression> <unresolved-name>
   //              ::= pt <expression> <unresolved-name>
-  if (base) {
-
-    // Ignore member expressions involving anonymous unions.
-    while (const auto *RT = base->getType()->getAs<RecordType>()) {
-      if (!RT->getDecl()->isAnonymousStructOrUnion())
-        break;
-      const auto *ME = dyn_cast<MemberExpr>(base);
-      if (!ME)
-        break;
-      base = ME->getBase();
-      isArrow = ME->isArrow();
-    }
-
-    if (base->isImplicitCXXThis()) {
-      // Note: GCC mangles member expressions to the implicit 'this' as
-      // *this., whereas we represent them as this->. The Itanium C++ ABI
-      // does not specify anything here, so we follow GCC.
-      Out << "dtdefpT";
-    } else {
-      Out << (isArrow ? "pt" : "dt");
-      mangleExpression(base);
-    }
-  }
-  mangleUnresolvedName(qualifier, firstQualifierLookup, member, arity);
+  if (base)
+    mangleMemberExprBase(base, isArrow);
+  mangleUnresolvedName(qualifier, member, arity);
 }
 
 /// Look at the callee of the given call expression and determine if
@@ -2592,6 +2630,13 @@ void CXXNameMangler::mangleCastExpression(const Expr *E, StringRef CastEncoding)
   mangleExpression(ECE->getSubExpr());
 }
 
+void CXXNameMangler::mangleInitListElements(const InitListExpr *InitList) {
+  if (auto *Syntactic = InitList->getSyntacticForm())
+    InitList = Syntactic;
+  for (unsigned i = 0, e = InitList->getNumInits(); i != e; ++i)
+    mangleExpression(InitList->getInit(i));
+}
+
 void CXXNameMangler::mangleExpression(const Expr *E, unsigned Arity) {
   // <expression> ::= <unary operator-name> <expression>
   //              ::= <binary operator-name> <expression> <expression>
@@ -2631,7 +2676,6 @@ recurse:
   // These all can only appear in local or variable-initialization
   // contexts and so should never appear in a mangling.
   case Expr::AddrLabelExprClass:
-  case Expr::DesignatedInitExprClass:
   case Expr::ImplicitValueInitExprClass:
   case Expr::ParenListExprClass:
   case Expr::LambdaExprClass:
@@ -2641,9 +2685,9 @@ recurse:
 
   // FIXME: invent manglings for all these.
   case Expr::BlockExprClass:
-  case Expr::CXXPseudoDestructorExprClass:
   case Expr::ChooseExprClass:
   case Expr::CompoundLiteralExprClass:
+  case Expr::DesignatedInitExprClass:
   case Expr::ExtVectorElementExprClass:
   case Expr::GenericSelectionExprClass:
   case Expr::ObjCEncodeExprClass:
@@ -2713,9 +2757,7 @@ recurse:
 
   case Expr::InitListExprClass: {
     Out << "il";
-    const InitListExpr *InitList = cast<InitListExpr>(E);
-    for (unsigned i = 0, e = InitList->getNumInits(); i != e; ++i)
-      mangleExpression(InitList->getInit(i));
+    mangleInitListElements(cast<InitListExpr>(E));
     Out << "E";
     break;
   }
@@ -2759,9 +2801,14 @@ recurse:
       Out << "cl";
     }
 
-    mangleExpression(CE->getCallee(), CE->getNumArgs());
-    for (unsigned I = 0, N = CE->getNumArgs(); I != N; ++I)
-      mangleExpression(CE->getArg(I));
+    unsigned CallArity = CE->getNumArgs();
+    for (const Expr *Arg : CE->arguments())
+      if (isa<PackExpansionExpr>(Arg))
+        CallArity = UnknownArity;
+
+    mangleExpression(CE->getCallee(), CallArity);
+    for (const Expr *Arg : CE->arguments())
+      mangleExpression(Arg);
     Out << 'E';
     break;
   }
@@ -2793,9 +2840,7 @@ recurse:
       } else if (New->getInitializationStyle() == CXXNewExpr::ListInit &&
                  isa<InitListExpr>(Init)) {
         // Only take InitListExprs apart for list-initialization.
-        const InitListExpr *InitList = cast<InitListExpr>(Init);
-        for (unsigned i = 0, e = InitList->getNumInits(); i != e; ++i)
-          mangleExpression(InitList->getInit(i));
+        mangleInitListElements(cast<InitListExpr>(Init));
       } else
         mangleExpression(Init);
     }
@@ -2803,6 +2848,33 @@ recurse:
     break;
   }
 
+  case Expr::CXXPseudoDestructorExprClass: {
+    const auto *PDE = cast<CXXPseudoDestructorExpr>(E);
+    if (const Expr *Base = PDE->getBase())
+      mangleMemberExprBase(Base, PDE->isArrow());
+    NestedNameSpecifier *Qualifier = PDE->getQualifier();
+    QualType ScopeType;
+    if (TypeSourceInfo *ScopeInfo = PDE->getScopeTypeInfo()) {
+      if (Qualifier) {
+        mangleUnresolvedPrefix(Qualifier,
+                               /*Recursive=*/true);
+        mangleUnresolvedTypeOrSimpleId(ScopeInfo->getType());
+        Out << 'E';
+      } else {
+        Out << "sr";
+        if (!mangleUnresolvedTypeOrSimpleId(ScopeInfo->getType()))
+          Out << 'E';
+      }
+    } else if (Qualifier) {
+      mangleUnresolvedPrefix(Qualifier);
+    }
+    // <base-unresolved-name> ::= dn <destructor-name>
+    Out << "dn";
+    QualType DestroyedType = PDE->getDestroyedType();
+    mangleUnresolvedTypeOrSimpleId(DestroyedType);
+    break;
+  }
+
   case Expr::MemberExprClass: {
     const MemberExpr *ME = cast<MemberExpr>(E);
     mangleMemberExpr(ME->getBase(), ME->isArrow(),
@@ -2813,9 +2885,9 @@ recurse:
 
   case Expr::UnresolvedMemberExprClass: {
     const UnresolvedMemberExpr *ME = cast<UnresolvedMemberExpr>(E);
-    mangleMemberExpr(ME->getBase(), ME->isArrow(),
-                     ME->getQualifier(), nullptr, ME->getMemberName(),
-                     Arity);
+    mangleMemberExpr(ME->isImplicitAccess() ? nullptr : ME->getBase(),
+                     ME->isArrow(), ME->getQualifier(), nullptr,
+                     ME->getMemberName(), Arity);
     if (ME->hasExplicitTemplateArgs())
       mangleTemplateArgs(ME->getExplicitTemplateArgs());
     break;
@@ -2824,8 +2896,9 @@ recurse:
   case Expr::CXXDependentScopeMemberExprClass: {
     const CXXDependentScopeMemberExpr *ME
       = cast<CXXDependentScopeMemberExpr>(E);
-    mangleMemberExpr(ME->getBase(), ME->isArrow(),
-                     ME->getQualifier(), ME->getFirstQualifierFoundInScope(),
+    mangleMemberExpr(ME->isImplicitAccess() ? nullptr : ME->getBase(),
+                     ME->isArrow(), ME->getQualifier(),
+                     ME->getFirstQualifierFoundInScope(),
                      ME->getMember(), Arity);
     if (ME->hasExplicitTemplateArgs())
       mangleTemplateArgs(ME->getExplicitTemplateArgs());
@@ -2834,7 +2907,7 @@ recurse:
 
   case Expr::UnresolvedLookupExprClass: {
     const UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(E);
-    mangleUnresolvedName(ULE->getQualifier(), nullptr, ULE->getName(), Arity);
+    mangleUnresolvedName(ULE->getQualifier(), ULE->getName(), Arity);
 
     // All the <unresolved-name> productions end in a
     // base-unresolved-name, where <template-args> are just tacked
@@ -2856,26 +2929,55 @@ recurse:
     break;
   }
 
-  case Expr::CXXTemporaryObjectExprClass:
   case Expr::CXXConstructExprClass: {
-    const CXXConstructExpr *CE = cast<CXXConstructExpr>(E);
+    const auto *CE = cast<CXXConstructExpr>(E);
+    if (!CE->isListInitialization() || CE->isStdInitListInitialization()) {
+      assert(
+          CE->getNumArgs() >= 1 &&
+          (CE->getNumArgs() == 1 || isa<CXXDefaultArgExpr>(CE->getArg(1))) &&
+          "implicit CXXConstructExpr must have one argument");
+      return mangleExpression(cast<CXXConstructExpr>(E)->getArg(0));
+    }
+    Out << "il";
+    for (auto *E : CE->arguments())
+      mangleExpression(E);
+    Out << "E";
+    break;
+  }
+
+  case Expr::CXXTemporaryObjectExprClass: {
+    const auto *CE = cast<CXXTemporaryObjectExpr>(E);
     unsigned N = CE->getNumArgs();
+    bool List = CE->isListInitialization();
 
-    if (CE->isListInitialization())
+    if (List)
       Out << "tl";
     else
       Out << "cv";
     mangleType(CE->getType());
-    if (N != 1) Out << '_';
-    for (unsigned I = 0; I != N; ++I) mangleExpression(CE->getArg(I));
-    if (N != 1) Out << 'E';
+    if (!List && N != 1)
+      Out << '_';
+    if (CE->isStdInitListInitialization()) {
+      // We implicitly created a std::initializer_list<T> for the first argument
+      // of a constructor of type U in an expression of the form U{a, b, c}.
+      // Strip all the semantic gunk off the initializer list.
+      auto *SILE =
+          cast<CXXStdInitializerListExpr>(CE->getArg(0)->IgnoreImplicit());
+      auto *ILE = cast<InitListExpr>(SILE->getSubExpr()->IgnoreImplicit());
+      mangleInitListElements(ILE);
+    } else {
+      for (auto *E : CE->arguments())
+        mangleExpression(E);
+    }
+    if (List || N != 1)
+      Out << 'E';
     break;
   }
 
   case Expr::CXXScalarValueInitExprClass:
-    Out <<"cv";
+    Out << "cv";
     mangleType(E->getType());
-    Out <<"_E";
+    Out << "_E";
     break;
 
   case Expr::CXXNoexceptExprClass:
@@ -3020,10 +3122,28 @@ recurse:
   // Fall through to mangle the cast itself.
       
   case Expr::CStyleCastExprClass:
-  case Expr::CXXFunctionalCastExprClass:
     mangleCastExpression(E, "cv");
     break;
 
+  case Expr::CXXFunctionalCastExprClass: {
+    auto *Sub = cast<ExplicitCastExpr>(E)->getSubExpr()->IgnoreImplicit();
+    // FIXME: Add isImplicit to CXXConstructExpr.
+    if (auto *CCE = dyn_cast<CXXConstructExpr>(Sub))
+      if (CCE->getParenOrBraceRange().isInvalid())
+        Sub = CCE->getArg(0)->IgnoreImplicit();
+    if (auto *StdInitList = dyn_cast<CXXStdInitializerListExpr>(Sub))
+      Sub = StdInitList->getSubExpr()->IgnoreImplicit();
+    if (auto *IL = dyn_cast<InitListExpr>(Sub)) {
+      Out << "tl";
+      mangleType(E->getType());
+      mangleInitListElements(IL);
+      Out << "E";
+    } else {
+      mangleCastExpression(E, "cv");
+    }
+    break;
+  }
+
   case Expr::CXXStaticCastExprClass:
     mangleCastExpression(E, "sc");
     break;
@@ -3058,7 +3178,7 @@ recurse:
     default:
       //  <expr-primary> ::= L <mangled-name> E # external name
       Out << 'L';
-      mangle(D, "_Z");
+      mangle(D);
       Out << 'E';
       break;
 
@@ -3101,8 +3221,7 @@ recurse:
 
   case Expr::DependentScopeDeclRefExprClass: {
     const DependentScopeDeclRefExpr *DRE = cast<DependentScopeDeclRefExpr>(E);
-    mangleUnresolvedName(DRE->getQualifier(), nullptr, DRE->getDeclName(),
-                         Arity);
+    mangleUnresolvedName(DRE->getQualifier(), DRE->getDeclName(), Arity);
 
     // All the <unresolved-name> productions end in a
     // base-unresolved-name, where <template-args> are just tacked
@@ -3327,6 +3446,9 @@ void CXXNameMangler::mangleCXXCtorType(CXXCtorType T) {
   case Ctor_Comdat:
     Out << "C5";
     break;
+  case Ctor_DefaultClosure:
+  case Ctor_CopyingClosure:
+    llvm_unreachable("closure constructors don't exist for the Itanium ABI!");
   }
 }
 
@@ -3410,8 +3532,8 @@ void CXXNameMangler::mangleTemplateArg(TemplateArgument A) {
     if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
       const ValueDecl *D = DRE->getDecl();
       if (isa<VarDecl>(D) || isa<FunctionDecl>(D)) {
-        Out << "L";
-        mangle(D, "_Z");
+        Out << 'L';
+        mangle(D);
         Out << 'E';
         break;
       }
@@ -3440,13 +3562,7 @@ void CXXNameMangler::mangleTemplateArg(TemplateArgument A) {
     Out << 'L';
     // References to external entities use the mangled name; if the name would
     // not normally be manged then mangle it as unqualified.
-    //
-    // FIXME: The ABI specifies that external names here should have _Z, but
-    // gcc leaves this off.
-    if (compensateMangling)
-      mangle(D, "_Z");
-    else
-      mangle(D, "Z");
+    mangle(D);
     Out << 'E';
 
     if (compensateMangling)
@@ -3524,8 +3640,8 @@ bool CXXNameMangler::mangleSubstitution(const NamedDecl *ND) {
   return mangleSubstitution(reinterpret_cast<uintptr_t>(ND));
 }
 
-/// \brief Determine whether the given type has any qualifiers that are
-/// relevant for substitutions.
+/// Determine whether the given type has any qualifiers that are relevant for
+/// substitutions.
 static bool hasMangledSubstitutionQualifiers(QualType T) {
   Qualifiers Qs = T.getQualifiers();
   return Qs.getCVRQualifiers() || Qs.hasAddressSpace();
@@ -3571,8 +3687,8 @@ static bool isCharType(QualType T) {
     T->isSpecificBuiltinType(BuiltinType::Char_U);
 }
 
-/// isCharSpecialization - Returns whether a given type is a template
-/// specialization of a given name with a single argument of type char.
+/// Returns whether a given type is a template specialization of a given name
+/// with a single argument of type char.
 static bool isCharSpecialization(QualType T, const char *Name) {
   if (T.isNull())
     return false;
@@ -3722,8 +3838,8 @@ void CXXNameMangler::addSubstitution(uintptr_t Ptr) {
 
 //
 
-/// \brief Mangles the name of the declaration D and emits that name to the
-/// given output stream.
+/// Mangles the name of the declaration D and emits that name to the given
+/// output stream.
 ///
 /// If the declaration D requires a mangled name, this routine will emit that
 /// mangled name to \p os and return true. Otherwise, \p os will be unchanged
@@ -3815,8 +3931,7 @@ void ItaniumMangleContextImpl::mangleCXXDtorThunk(
   Mangler.mangleFunctionEncoding(DD);
 }
 
-/// mangleGuardVariable - Returns the mangled name for a guard variable
-/// for the passed in VarDecl.
+/// Returns the mangled name for a guard variable for the passed in VarDecl.
 void ItaniumMangleContextImpl::mangleStaticGuardVariable(const VarDecl *D,
                                                          raw_ostream &Out) {
   //  <special-name> ::= GV <object name>       # Guard variable for one-time
@@ -3845,6 +3960,26 @@ void ItaniumMangleContextImpl::mangleDynamicAtExitDestructor(const VarDecl *D,
     Mangler.getStream() << D->getName();
 }
 
+void ItaniumMangleContextImpl::mangleSEHFilterExpression(
+    const NamedDecl *EnclosingDecl, raw_ostream &Out) {
+  CXXNameMangler Mangler(*this, Out);
+  Mangler.getStream() << "__filt_";
+  if (shouldMangleDeclName(EnclosingDecl))
+    Mangler.mangle(EnclosingDecl);
+  else
+    Mangler.getStream() << EnclosingDecl->getName();
+}
+
+void ItaniumMangleContextImpl::mangleSEHFinallyBlock(
+    const NamedDecl *EnclosingDecl, raw_ostream &Out) {
+  CXXNameMangler Mangler(*this, Out);
+  Mangler.getStream() << "__fin_";
+  if (shouldMangleDeclName(EnclosingDecl))
+    Mangler.mangle(EnclosingDecl);
+  else
+    Mangler.getStream() << EnclosingDecl->getName();
+}
+
 void ItaniumMangleContextImpl::mangleItaniumThreadLocalInit(const VarDecl *D,
                                                             raw_ostream &Out) {
   //  <special-name> ::= TH <object name>
@@ -3923,6 +4058,22 @@ void ItaniumMangleContextImpl::mangleTypeName(QualType Ty, raw_ostream &Out) {
   mangleCXXRTTIName(Ty, Out);
 }
 
+void ItaniumMangleContextImpl::mangleCXXVTableBitSet(const CXXRecordDecl *RD,
+                                                     raw_ostream &Out) {
+  Linkage L = RD->getLinkageInternal();
+  if (L == InternalLinkage || L == UniqueExternalLinkage) {
+    // This part of the identifier needs to be unique across all translation
+    // units in the linked program. The scheme fails if multiple translation
+    // units are compiled using the same relative source file path, or if
+    // multiple translation units are built from the same source file.
+    SourceManager &SM = getASTContext().getSourceManager();
+    Out << "[" << SM.getFileEntryForID(SM.getMainFileID())->getName() << "]";
+  }
+
+  CXXNameMangler Mangler(*this, Out);
+  Mangler.mangleType(QualType(RD->getTypeForDecl(), 0));
+}
+
 void ItaniumMangleContextImpl::mangleStringLiteral(const StringLiteral *, raw_ostream &) {
   llvm_unreachable("Can't mangle string literals");
 }
diff --git a/lib/AST/MicrosoftCXXABI.cpp b/lib/AST/MicrosoftCXXABI.cpp
index 0603d3b7b9b5..93ff77a2e964 100644
--- a/lib/AST/MicrosoftCXXABI.cpp
+++ b/lib/AST/MicrosoftCXXABI.cpp
@@ -31,11 +31,12 @@ class MicrosoftNumberingContext : public MangleNumberingContext {
   llvm::DenseMap<const Type *, unsigned> ManglingNumbers;
   unsigned LambdaManglingNumber;
   unsigned StaticLocalNumber;
+  unsigned StaticThreadlocalNumber;
 
 public:
   MicrosoftNumberingContext()
       : MangleNumberingContext(), LambdaManglingNumber(0),
-        StaticLocalNumber(0) {}
+        StaticLocalNumber(0), StaticThreadlocalNumber(0) {}
 
   unsigned getManglingNumber(const CXXMethodDecl *CallOperator) override {
     return ++LambdaManglingNumber;
@@ -47,6 +48,8 @@ public:
   }
 
   unsigned getStaticLocalNumber(const VarDecl *VD) override {
+    if (VD->getTLSKind())
+      return ++StaticThreadlocalNumber;
     return ++StaticLocalNumber;
   }
 
@@ -63,6 +66,10 @@ public:
 
 class MicrosoftCXXABI : public CXXABI {
   ASTContext &Context;
+  llvm::SmallDenseMap<CXXRecordDecl *, CXXConstructorDecl *> RecordToCopyCtor;
+  llvm::SmallDenseMap<std::pair<const CXXConstructorDecl *, unsigned>, Expr *>
+      CtorToDefaultArgExpr;
+
 public:
   MicrosoftCXXABI(ASTContext &Ctx) : Context(Ctx) { }
 
@@ -82,13 +89,36 @@ public:
       return false;
 
     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
-    
+
     // In the Microsoft ABI, classes can have one or two vtable pointers.
-    CharUnits PointerSize = 
-      Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
+    CharUnits PointerSize =
+        Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
     return Layout.getNonVirtualSize() == PointerSize ||
       Layout.getNonVirtualSize() == PointerSize * 2;
-  }    
+  }
+
+  void addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                       unsigned ParmIdx, Expr *DAE) override {
+    CtorToDefaultArgExpr[std::make_pair(CD, ParmIdx)] = DAE;
+  }
+
+  Expr *getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                        unsigned ParmIdx) override {
+    return CtorToDefaultArgExpr[std::make_pair(CD, ParmIdx)];
+  }
+
+  const CXXConstructorDecl *
+  getCopyConstructorForExceptionObject(CXXRecordDecl *RD) override {
+    return RecordToCopyCtor[RD];
+  }
+
+  void
+  addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
+                                       CXXConstructorDecl *CD) override {
+    assert(CD != nullptr);
+    assert(RecordToCopyCtor[RD] == nullptr || RecordToCopyCtor[RD] == CD);
+    RecordToCopyCtor[RD] = CD;
+  }
 
   MangleNumberingContext *createMangleNumberingContext() const override {
     return new MicrosoftNumberingContext();
@@ -186,29 +216,28 @@ getMSMemberPointerSlots(const MemberPointerType *MPT) {
 
 std::pair<uint64_t, unsigned> MicrosoftCXXABI::getMemberPointerWidthAndAlign(
     const MemberPointerType *MPT) const {
-  const TargetInfo &Target = Context.getTargetInfo();
-  assert(Target.getTriple().getArch() == llvm::Triple::x86 ||
-         Target.getTriple().getArch() == llvm::Triple::x86_64);
-  unsigned Ptrs, Ints;
-  std::tie(Ptrs, Ints) = getMSMemberPointerSlots(MPT);
   // The nominal struct is laid out with pointers followed by ints and aligned
   // to a pointer width if any are present and an int width otherwise.
+  const TargetInfo &Target = Context.getTargetInfo();
   unsigned PtrSize = Target.getPointerWidth(0);
   unsigned IntSize = Target.getIntWidth();
+
+  unsigned Ptrs, Ints;
+  std::tie(Ptrs, Ints) = getMSMemberPointerSlots(MPT);
   uint64_t Width = Ptrs * PtrSize + Ints * IntSize;
   unsigned Align;
 
   // When MSVC does x86_32 record layout, it aligns aggregate member pointers to
   // 8 bytes.  However, __alignof usually returns 4 for data memptrs and 8 for
   // function memptrs.
-  if (Ptrs + Ints > 1 && Target.getTriple().getArch() == llvm::Triple::x86)
-    Align = 8 * 8;
+  if (Ptrs + Ints > 1 && Target.getTriple().isArch32Bit())
+    Align = 64;
   else if (Ptrs)
     Align = Target.getPointerAlign(0);
   else
     Align = Target.getIntAlign();
 
-  if (Target.getTriple().getArch() == llvm::Triple::x86_64)
+  if (Target.getTriple().isArch64Bit())
     Width = llvm::RoundUpToAlignment(Width, Align);
   return std::make_pair(Width, Align);
 }
diff --git a/lib/AST/MicrosoftMangle.cpp b/lib/AST/MicrosoftMangle.cpp
index 72f90f67cbdf..77522c1f9c5d 100644
--- a/lib/AST/MicrosoftMangle.cpp
+++ b/lib/AST/MicrosoftMangle.cpp
@@ -67,11 +67,15 @@ static const DeclContext *getEffectiveParentContext(const DeclContext *DC) {
   return getEffectiveDeclContext(cast<Decl>(DC));
 }
 
-static const FunctionDecl *getStructor(const FunctionDecl *fn) {
-  if (const FunctionTemplateDecl *ftd = fn->getPrimaryTemplate())
-    return ftd->getTemplatedDecl();
+static const FunctionDecl *getStructor(const NamedDecl *ND) {
+  if (const auto *FTD = dyn_cast<FunctionTemplateDecl>(ND))
+    return FTD->getTemplatedDecl();
 
-  return fn;
+  const auto *FD = cast<FunctionDecl>(ND);
+  if (const auto *FTD = FD->getPrimaryTemplate())
+    return FTD->getTemplatedDecl();
+
+  return FD;
 }
 
 static bool isLambda(const NamedDecl *ND) {
@@ -89,6 +93,8 @@ class MicrosoftMangleContextImpl : public MicrosoftMangleContext {
   llvm::DenseMap<DiscriminatorKeyTy, unsigned> Discriminator;
   llvm::DenseMap<const NamedDecl *, unsigned> Uniquifier;
   llvm::DenseMap<const CXXRecordDecl *, unsigned> LambdaIds;
+  llvm::DenseMap<const NamedDecl *, unsigned> SEHFilterIds;
+  llvm::DenseMap<const NamedDecl *, unsigned> SEHFinallyIds;
 
 public:
   MicrosoftMangleContextImpl(ASTContext &Context, DiagnosticsEngine &Diags)
@@ -109,6 +115,16 @@ public:
   void mangleCXXVBTable(const CXXRecordDecl *Derived,
                         ArrayRef<const CXXRecordDecl *> BasePath,
                         raw_ostream &Out) override;
+  void mangleCXXThrowInfo(QualType T, bool IsConst, bool IsVolatile,
+                          uint32_t NumEntries, raw_ostream &Out) override;
+  void mangleCXXCatchableTypeArray(QualType T, uint32_t NumEntries,
+                                   raw_ostream &Out) override;
+  void mangleCXXCatchableType(QualType T, const CXXConstructorDecl *CD,
+                              CXXCtorType CT, uint32_t Size, uint32_t NVOffset,
+                              int32_t VBPtrOffset, uint32_t VBIndex,
+                              raw_ostream &Out) override;
+  void mangleCXXCatchHandlerType(QualType T, uint32_t Flags,
+                                 raw_ostream &Out) override;
   void mangleCXXRTTI(QualType T, raw_ostream &Out) override;
   void mangleCXXRTTIName(QualType T, raw_ostream &Out) override;
   void mangleCXXRTTIBaseClassDescriptor(const CXXRecordDecl *Derived,
@@ -131,10 +147,18 @@ public:
   void mangleReferenceTemporary(const VarDecl *, unsigned ManglingNumber,
                                 raw_ostream &) override;
   void mangleStaticGuardVariable(const VarDecl *D, raw_ostream &Out) override;
+  void mangleThreadSafeStaticGuardVariable(const VarDecl *D, unsigned GuardNum,
+                                           raw_ostream &Out) override;
   void mangleDynamicInitializer(const VarDecl *D, raw_ostream &Out) override;
   void mangleDynamicAtExitDestructor(const VarDecl *D,
                                      raw_ostream &Out) override;
+  void mangleSEHFilterExpression(const NamedDecl *EnclosingDecl,
+                                 raw_ostream &Out) override;
+  void mangleSEHFinallyBlock(const NamedDecl *EnclosingDecl,
+                             raw_ostream &Out) override;
   void mangleStringLiteral(const StringLiteral *SL, raw_ostream &Out) override;
+  void mangleCXXVTableBitSet(const CXXRecordDecl *RD,
+                             raw_ostream &Out) override;
   bool getNextDiscriminator(const NamedDecl *ND, unsigned &disc) {
     // Lambda closure types are already numbered.
     if (isLambda(ND))
@@ -211,6 +235,12 @@ public:
                          64) {}
 
   MicrosoftCXXNameMangler(MicrosoftMangleContextImpl &C, raw_ostream &Out_,
+                          const CXXConstructorDecl *D, CXXCtorType Type)
+      : Context(C), Out(Out_), Structor(getStructor(D)), StructorType(Type),
+        PointersAre64Bit(C.getASTContext().getTargetInfo().getPointerWidth(0) ==
+                         64) {}
+
+  MicrosoftCXXNameMangler(MicrosoftMangleContextImpl &C, raw_ostream &Out_,
                           const CXXDestructorDecl *D, CXXDtorType Type)
       : Context(C), Out(Out_), Structor(getStructor(D)), StructorType(Type),
         PointersAre64Bit(C.getASTContext().getTargetInfo().getPointerWidth(0) ==
@@ -220,7 +250,7 @@ public:
 
   void mangle(const NamedDecl *D, StringRef Prefix = "\01?");
   void mangleName(const NamedDecl *ND);
-  void mangleFunctionEncoding(const FunctionDecl *FD);
+  void mangleFunctionEncoding(const FunctionDecl *FD, bool ShouldMangle);
   void mangleVariableEncoding(const VarDecl *VD);
   void mangleMemberDataPointer(const CXXRecordDecl *RD, const ValueDecl *VD);
   void mangleMemberFunctionPointer(const CXXRecordDecl *RD,
@@ -247,7 +277,7 @@ private:
   void mangleQualifiers(Qualifiers Quals, bool IsMember);
   void mangleRefQualifier(RefQualifierKind RefQualifier);
   void manglePointerCVQualifiers(Qualifiers Quals);
-  void manglePointerExtQualifiers(Qualifiers Quals, const Type *PointeeType);
+  void manglePointerExtQualifiers(Qualifiers Quals, QualType PointeeType);
 
   void mangleUnscopedTemplateName(const TemplateDecl *ND);
   void
@@ -261,6 +291,7 @@ private:
 #define ABSTRACT_TYPE(CLASS, PARENT)
 #define NON_CANONICAL_TYPE(CLASS, PARENT)
 #define TYPE(CLASS, PARENT) void mangleType(const CLASS##Type *T, \
+                                            Qualifiers Quals, \
                                             SourceRange Range);
 #include "clang/AST/TypeNodes.def"
 #undef ABSTRACT_TYPE
@@ -271,6 +302,7 @@ private:
   void mangleDecayedArrayType(const ArrayType *T);
   void mangleArrayType(const ArrayType *T);
   void mangleFunctionClass(const FunctionDecl *FD);
+  void mangleCallingConvention(CallingConv CC);
   void mangleCallingConvention(const FunctionType *T);
   void mangleIntegerLiteral(const llvm::APSInt &Number, bool IsBoolean);
   void mangleExpression(const Expr *E);
@@ -352,7 +384,7 @@ void MicrosoftCXXNameMangler::mangle(const NamedDecl *D, StringRef Prefix) {
   Out << Prefix;
   mangleName(D);
   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
-    mangleFunctionEncoding(FD);
+    mangleFunctionEncoding(FD, Context.shouldMangleDeclName(FD));
   else if (const VarDecl *VD = dyn_cast<VarDecl>(D))
     mangleVariableEncoding(VD);
   else {
@@ -365,7 +397,8 @@ void MicrosoftCXXNameMangler::mangle(const NamedDecl *D, StringRef Prefix) {
   }
 }
 
-void MicrosoftCXXNameMangler::mangleFunctionEncoding(const FunctionDecl *FD) {
+void MicrosoftCXXNameMangler::mangleFunctionEncoding(const FunctionDecl *FD,
+                                                     bool ShouldMangle) {
   // <type-encoding> ::= <function-class> <function-type>
 
   // Since MSVC operates on the type as written and not the canonical type, it
@@ -380,13 +413,20 @@ void MicrosoftCXXNameMangler::mangleFunctionEncoding(const FunctionDecl *FD) {
   // extern "C" functions can hold entities that must be mangled.
   // As it stands, these functions still need to get expressed in the full
   // external name.  They have their class and type omitted, replaced with '9'.
-  if (Context.shouldMangleDeclName(FD)) {
-    // First, the function class.
+  if (ShouldMangle) {
+    // We would like to mangle all extern "C" functions using this additional
+    // component but this would break compatibility with MSVC's behavior.
+    // Instead, do this when we know that compatibility isn't important (in
+    // other words, when it is an overloaded extern "C" funciton).
+    if (FD->isExternC() && FD->hasAttr<OverloadableAttr>())
+      Out << "$$J0";
+
     mangleFunctionClass(FD);
 
     mangleFunctionType(FT, FD);
-  } else
+  } else {
     Out << '9';
+  }
 }
 
 void MicrosoftCXXNameMangler::mangleVariableEncoding(const VarDecl *VD) {
@@ -422,7 +462,7 @@ void MicrosoftCXXNameMangler::mangleVariableEncoding(const VarDecl *VD) {
       Ty->isMemberPointerType()) {
     mangleType(Ty, SR, QMM_Drop);
     manglePointerExtQualifiers(
-        Ty.getDesugaredType(getASTContext()).getLocalQualifiers(), nullptr);
+        Ty.getDesugaredType(getASTContext()).getLocalQualifiers(), QualType());
     if (const MemberPointerType *MPT = Ty->getAs<MemberPointerType>()) {
       mangleQualifiers(MPT->getPointeeType().getQualifiers(), true);
       // Member pointers are suffixed with a back reference to the member
@@ -525,7 +565,7 @@ MicrosoftCXXNameMangler::mangleMemberFunctionPointer(const CXXRecordDecl *RD,
       }
     } else {
       mangleName(MD);
-      mangleFunctionEncoding(MD);
+      mangleFunctionEncoding(MD, /*ShouldMangle=*/true);
     }
   } else {
     // Null single inheritance member functions are encoded as a simple nullptr.
@@ -559,7 +599,7 @@ void MicrosoftCXXNameMangler::mangleVirtualMemPtrThunk(
   Out << "$B";
   mangleNumber(OffsetInVFTable);
   Out << 'A';
-  Out << (PointersAre64Bit ? 'A' : 'E');
+  mangleCallingConvention(MD->getType()->getAs<FunctionProtoType>());
 }
 
 void MicrosoftCXXNameMangler::mangleName(const NamedDecl *ND) {
@@ -757,12 +797,18 @@ void MicrosoftCXXNameMangler::mangleUnqualifiedName(const NamedDecl *ND,
       llvm_unreachable("Can't mangle Objective-C selector names here!");
 
     case DeclarationName::CXXConstructorName:
-      if (ND == Structor) {
-        assert(StructorType == Ctor_Complete &&
-               "Should never be asked to mangle a ctor other than complete");
+      if (Structor == getStructor(ND)) {
+        if (StructorType == Ctor_CopyingClosure) {
+          Out << "?_O";
+          return;
+        }
+        if (StructorType == Ctor_DefaultClosure) {
+          Out << "?_F";
+          return;
+        }
       }
       Out << "?0";
-      break;
+      return;
 
     case DeclarationName::CXXDestructorName:
       if (ND == Structor)
@@ -1134,10 +1180,13 @@ void MicrosoftCXXNameMangler::mangleTemplateArg(const TemplateDecl *TD,
           cast<ValueDecl>(ND));
     } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) {
       const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
-      if (MD && MD->isInstance())
+      if (MD && MD->isInstance()) {
         mangleMemberFunctionPointer(MD->getParent()->getMostRecentDecl(), MD);
-      else
-        mangle(FD, "$1?");
+      } else {
+        Out << "$1?";
+        mangleName(FD);
+        mangleFunctionEncoding(FD, /*ShouldMangle=*/true);
+      }
     } else {
       mangle(ND, TA.getParamTypeForDecl()->isReferenceType() ? "$E?" : "$1?");
     }
@@ -1171,7 +1220,12 @@ void MicrosoftCXXNameMangler::mangleTemplateArg(const TemplateDecl *TD,
     if (TemplateArgs.empty()) {
       if (isa<TemplateTypeParmDecl>(Parm) ||
           isa<TemplateTemplateParmDecl>(Parm))
-        Out << "$$V";
+        // MSVC 2015 changed the mangling for empty expanded template packs,
+        // use the old mangling for link compatibility for old versions.
+        Out << (Context.getASTContext().getLangOpts().isCompatibleWithMSVC(
+                    LangOptions::MSVC2015)
+                    ? "$$V"
+                    : "$$$V");
       else if (isa<NonTypeTemplateParmDecl>(Parm))
         Out << "$S";
       else
@@ -1298,11 +1352,11 @@ MicrosoftCXXNameMangler::mangleRefQualifier(RefQualifierKind RefQualifier) {
   }
 }
 
-void
-MicrosoftCXXNameMangler::manglePointerExtQualifiers(Qualifiers Quals,
-                                                    const Type *PointeeType) {
+void MicrosoftCXXNameMangler::manglePointerExtQualifiers(Qualifiers Quals,
+                                                         QualType PointeeType) {
   bool HasRestrict = Quals.hasRestrict();
-  if (PointersAre64Bit && (!PointeeType || !PointeeType->isFunctionType()))
+  if (PointersAre64Bit &&
+      (PointeeType.isNull() || !PointeeType->isFunctionType()))
     Out << 'E';
 
   if (HasRestrict)
@@ -1338,29 +1392,38 @@ void MicrosoftCXXNameMangler::mangleArgumentType(QualType T,
   // e.g.
   // void (*x)(void) will not form a backreference with void x(void)
   void *TypePtr;
-  if (const DecayedType *DT = T->getAs<DecayedType>()) {
-    TypePtr = DT->getOriginalType().getCanonicalType().getAsOpaquePtr();
+  if (const auto *DT = T->getAs<DecayedType>()) {
+    QualType OriginalType = DT->getOriginalType();
+    // All decayed ArrayTypes should be treated identically; as-if they were
+    // a decayed IncompleteArrayType.
+    if (const auto *AT = getASTContext().getAsArrayType(OriginalType))
+      OriginalType = getASTContext().getIncompleteArrayType(
+          AT->getElementType(), AT->getSizeModifier(),
+          AT->getIndexTypeCVRQualifiers());
+
+    TypePtr = OriginalType.getCanonicalType().getAsOpaquePtr();
     // If the original parameter was textually written as an array,
     // instead treat the decayed parameter like it's const.
     //
     // e.g.
     // int [] -> int * const
-    if (DT->getOriginalType()->isArrayType())
+    if (OriginalType->isArrayType())
       T = T.withConst();
-  } else
+  } else {
     TypePtr = T.getCanonicalType().getAsOpaquePtr();
+  }
 
   ArgBackRefMap::iterator Found = TypeBackReferences.find(TypePtr);
 
   if (Found == TypeBackReferences.end()) {
-    size_t OutSizeBefore = Out.GetNumBytesInBuffer();
+    size_t OutSizeBefore = Out.tell();
 
     mangleType(T, Range, QMM_Drop);
 
     // See if it's worth creating a back reference.
     // Only types longer than 1 character are considered
     // and only 10 back references slots are available:
-    bool LongerThanOneChar = (Out.GetNumBytesInBuffer() - OutSizeBefore > 1);
+    bool LongerThanOneChar = (Out.tell() - OutSizeBefore > 1);
     if (LongerThanOneChar && TypeBackReferences.size() < 10) {
       size_t Size = TypeBackReferences.size();
       TypeBackReferences[TypePtr] = Size;
@@ -1388,7 +1451,7 @@ void MicrosoftCXXNameMangler::mangleType(QualType T, SourceRange Range,
   }
 
   bool IsPointer = T->isAnyPointerType() || T->isMemberPointerType() ||
-                   T->isBlockPointerType();
+                   T->isReferenceType() || T->isBlockPointerType();
 
   switch (QMM) {
   case QMM_Drop:
@@ -1415,11 +1478,6 @@ void MicrosoftCXXNameMangler::mangleType(QualType T, SourceRange Range,
     break;
   }
 
-  // We have to mangle these now, while we still have enough information.
-  if (IsPointer) {
-    manglePointerCVQualifiers(Quals);
-    manglePointerExtQualifiers(Quals, T->getPointeeType().getTypePtr());
-  }
   const Type *ty = T.getTypePtr();
 
   switch (ty->getTypeClass()) {
@@ -1430,7 +1488,7 @@ void MicrosoftCXXNameMangler::mangleType(QualType T, SourceRange Range,
     return;
 #define TYPE(CLASS, PARENT) \
   case Type::CLASS: \
-    mangleType(cast<CLASS##Type>(ty), Range); \
+    mangleType(cast<CLASS##Type>(ty), Quals, Range); \
     break;
 #include "clang/AST/TypeNodes.def"
 #undef ABSTRACT_TYPE
@@ -1439,7 +1497,7 @@ void MicrosoftCXXNameMangler::mangleType(QualType T, SourceRange Range,
   }
 }
 
-void MicrosoftCXXNameMangler::mangleType(const BuiltinType *T,
+void MicrosoftCXXNameMangler::mangleType(const BuiltinType *T, Qualifiers,
                                          SourceRange Range) {
   //  <type>         ::= <builtin-type>
   //  <builtin-type> ::= X  # void
@@ -1525,7 +1583,7 @@ void MicrosoftCXXNameMangler::mangleType(const BuiltinType *T,
 }
 
 // <type>          ::= <function-type>
-void MicrosoftCXXNameMangler::mangleType(const FunctionProtoType *T,
+void MicrosoftCXXNameMangler::mangleType(const FunctionProtoType *T, Qualifiers,
                                          SourceRange) {
   // Structors only appear in decls, so at this point we know it's not a
   // structor type.
@@ -1539,7 +1597,7 @@ void MicrosoftCXXNameMangler::mangleType(const FunctionProtoType *T,
   }
 }
 void MicrosoftCXXNameMangler::mangleType(const FunctionNoProtoType *T,
-                                         SourceRange) {
+                                         Qualifiers, SourceRange) {
   llvm_unreachable("Can't mangle K&R function prototypes");
 }
 
@@ -1553,24 +1611,34 @@ void MicrosoftCXXNameMangler::mangleFunctionType(const FunctionType *T,
   SourceRange Range;
   if (D) Range = D->getSourceRange();
 
-  bool IsStructor = false, HasThisQuals = ForceThisQuals;
+  bool IsStructor = false, HasThisQuals = ForceThisQuals, IsCtorClosure = false;
+  CallingConv CC = T->getCallConv();
   if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(D)) {
     if (MD->isInstance())
       HasThisQuals = true;
-    if (isa<CXXConstructorDecl>(MD) || isa<CXXDestructorDecl>(MD))
+    if (isa<CXXDestructorDecl>(MD)) {
+      IsStructor = true;
+    } else if (isa<CXXConstructorDecl>(MD)) {
       IsStructor = true;
+      IsCtorClosure = (StructorType == Ctor_CopyingClosure ||
+                       StructorType == Ctor_DefaultClosure) &&
+                      getStructor(MD) == Structor;
+      if (IsCtorClosure)
+        CC = getASTContext().getDefaultCallingConvention(
+            /*IsVariadic=*/false, /*IsCXXMethod=*/true);
+    }
   }
 
   // If this is a C++ instance method, mangle the CVR qualifiers for the
   // this pointer.
   if (HasThisQuals) {
     Qualifiers Quals = Qualifiers::fromCVRMask(Proto->getTypeQuals());
-    manglePointerExtQualifiers(Quals, /*PointeeType=*/nullptr);
+    manglePointerExtQualifiers(Quals, /*PointeeType=*/QualType());
     mangleRefQualifier(Proto->getRefQualifier());
     mangleQualifiers(Quals, /*IsMember=*/false);
   }
 
-  mangleCallingConvention(T);
+  mangleCallingConvention(CC);
 
   // <return-type> ::= <type>
   //               ::= @ # structors (they have no declared return type)
@@ -1584,6 +1652,29 @@ void MicrosoftCXXNameMangler::mangleFunctionType(const FunctionType *T,
       Out << (PointersAre64Bit ? "PEAXI@Z" : "PAXI@Z");
       return;
     }
+    if (IsCtorClosure) {
+      // Default constructor closure and copy constructor closure both return
+      // void.
+      Out << 'X';
+
+      if (StructorType == Ctor_DefaultClosure) {
+        // Default constructor closure always has no arguments.
+        Out << 'X';
+      } else if (StructorType == Ctor_CopyingClosure) {
+        // Copy constructor closure always takes an unqualified reference.
+        mangleArgumentType(getASTContext().getLValueReferenceType(
+                               Proto->getParamType(0)
+                                   ->getAs<LValueReferenceType>()
+                                   ->getPointeeType(),
+                               /*SpelledAsLValue=*/true),
+                           Range);
+        Out << '@';
+      } else {
+        llvm_unreachable("unexpected constructor closure!");
+      }
+      Out << 'Z';
+      return;
+    }
     Out << '@';
   } else {
     QualType ResultType = Proto->getReturnType();
@@ -1608,7 +1699,7 @@ void MicrosoftCXXNameMangler::mangleFunctionType(const FunctionType *T,
     Out << 'X';
   } else {
     // Happens for function pointer type arguments for example.
-    for (const QualType Arg : Proto->param_types())
+    for (const QualType &Arg : Proto->param_types())
       mangleArgumentType(Arg, Range);
     // <builtin-type>      ::= Z  # ellipsis
     if (Proto->isVariadic())
@@ -1673,10 +1764,11 @@ void MicrosoftCXXNameMangler::mangleFunctionClass(const FunctionDecl *FD) {
         else
           Out << 'Q';
     }
-  } else
+  } else {
     Out << 'Y';
+  }
 }
-void MicrosoftCXXNameMangler::mangleCallingConvention(const FunctionType *T) {
+void MicrosoftCXXNameMangler::mangleCallingConvention(CallingConv CC) {
   // <calling-convention> ::= A # __cdecl
   //                      ::= B # __export __cdecl
   //                      ::= C # __pascal
@@ -1693,7 +1785,7 @@ void MicrosoftCXXNameMangler::mangleCallingConvention(const FunctionType *T) {
   // that keyword. (It didn't actually export them, it just made them so
   // that they could be in a DLL and somebody from another module could call
   // them.)
-  CallingConv CC = T->getCallConv();
+
   switch (CC) {
     default:
       llvm_unreachable("Unsupported CC for mangling");
@@ -1707,6 +1799,9 @@ void MicrosoftCXXNameMangler::mangleCallingConvention(const FunctionType *T) {
     case CC_X86VectorCall: Out << 'Q'; break;
   }
 }
+void MicrosoftCXXNameMangler::mangleCallingConvention(const FunctionType *T) {
+  mangleCallingConvention(T->getCallConv());
+}
 void MicrosoftCXXNameMangler::mangleThrowSpecification(
                                                 const FunctionProtoType *FT) {
   // <throw-spec> ::= Z # throw(...) (default)
@@ -1719,7 +1814,7 @@ void MicrosoftCXXNameMangler::mangleThrowSpecification(
 }
 
 void MicrosoftCXXNameMangler::mangleType(const UnresolvedUsingType *T,
-                                         SourceRange Range) {
+                                         Qualifiers, SourceRange Range) {
   // Probably should be mangled as a template instantiation; need to see what
   // VC does first.
   DiagnosticsEngine &Diags = Context.getDiags();
@@ -1734,10 +1829,12 @@ void MicrosoftCXXNameMangler::mangleType(const UnresolvedUsingType *T,
 // <struct-type> ::= U <name>
 // <class-type>  ::= V <name>
 // <enum-type>   ::= W4 <name>
-void MicrosoftCXXNameMangler::mangleType(const EnumType *T, SourceRange) {
+void MicrosoftCXXNameMangler::mangleType(const EnumType *T, Qualifiers,
+                                         SourceRange) {
   mangleType(cast<TagType>(T)->getDecl());
 }
-void MicrosoftCXXNameMangler::mangleType(const RecordType *T, SourceRange) {
+void MicrosoftCXXNameMangler::mangleType(const RecordType *T, Qualifiers,
+                                         SourceRange) {
   mangleType(cast<TagType>(T)->getDecl());
 }
 void MicrosoftCXXNameMangler::mangleType(const TagDecl *TD) {
@@ -1772,39 +1869,41 @@ void MicrosoftCXXNameMangler::mangleDecayedArrayType(const ArrayType *T) {
   manglePointerCVQualifiers(T->getElementType().getQualifiers());
   mangleType(T->getElementType(), SourceRange());
 }
-void MicrosoftCXXNameMangler::mangleType(const ConstantArrayType *T,
+void MicrosoftCXXNameMangler::mangleType(const ConstantArrayType *T, Qualifiers,
                                          SourceRange) {
   llvm_unreachable("Should have been special cased");
 }
-void MicrosoftCXXNameMangler::mangleType(const VariableArrayType *T,
+void MicrosoftCXXNameMangler::mangleType(const VariableArrayType *T, Qualifiers,
                                          SourceRange) {
   llvm_unreachable("Should have been special cased");
 }
 void MicrosoftCXXNameMangler::mangleType(const DependentSizedArrayType *T,
-                                         SourceRange) {
+                                         Qualifiers, SourceRange) {
   llvm_unreachable("Should have been special cased");
 }
 void MicrosoftCXXNameMangler::mangleType(const IncompleteArrayType *T,
-                                         SourceRange) {
+                                         Qualifiers, SourceRange) {
   llvm_unreachable("Should have been special cased");
 }
 void MicrosoftCXXNameMangler::mangleArrayType(const ArrayType *T) {
   QualType ElementTy(T, 0);
   SmallVector<llvm::APInt, 3> Dimensions;
   for (;;) {
-    if (const ConstantArrayType *CAT =
-            getASTContext().getAsConstantArrayType(ElementTy)) {
+    if (ElementTy->isConstantArrayType()) {
+      const ConstantArrayType *CAT =
+          getASTContext().getAsConstantArrayType(ElementTy);
       Dimensions.push_back(CAT->getSize());
       ElementTy = CAT->getElementType();
+    } else if (ElementTy->isIncompleteArrayType()) {
+      const IncompleteArrayType *IAT =
+          getASTContext().getAsIncompleteArrayType(ElementTy);
+      Dimensions.push_back(llvm::APInt(32, 0));
+      ElementTy = IAT->getElementType();
     } else if (ElementTy->isVariableArrayType()) {
       const VariableArrayType *VAT =
         getASTContext().getAsVariableArrayType(ElementTy);
-      DiagnosticsEngine &Diags = Context.getDiags();
-      unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
-        "cannot mangle this variable-length array yet");
-      Diags.Report(VAT->getSizeExpr()->getExprLoc(), DiagID)
-        << VAT->getBracketsRange();
-      return;
+      Dimensions.push_back(llvm::APInt(32, 0));
+      ElementTy = VAT->getElementType();
     } else if (ElementTy->isDependentSizedArrayType()) {
       // The dependent expression has to be folded into a constant (TODO).
       const DependentSizedArrayType *DSAT =
@@ -1815,12 +1914,9 @@ void MicrosoftCXXNameMangler::mangleArrayType(const ArrayType *T) {
       Diags.Report(DSAT->getSizeExpr()->getExprLoc(), DiagID)
         << DSAT->getBracketsRange();
       return;
-    } else if (const IncompleteArrayType *IAT =
-                   getASTContext().getAsIncompleteArrayType(ElementTy)) {
-      Dimensions.push_back(llvm::APInt(32, 0));
-      ElementTy = IAT->getElementType();
+    } else {
+      break;
     }
-    else break;
   }
   Out << 'Y';
   // <dimension-count> ::= <number> # number of extra dimensions
@@ -1833,9 +1929,11 @@ void MicrosoftCXXNameMangler::mangleArrayType(const ArrayType *T) {
 // <type>                   ::= <pointer-to-member-type>
 // <pointer-to-member-type> ::= <pointer-cvr-qualifiers> <cvr-qualifiers>
 //                                                          <class name> <type>
-void MicrosoftCXXNameMangler::mangleType(const MemberPointerType *T,
+void MicrosoftCXXNameMangler::mangleType(const MemberPointerType *T, Qualifiers Quals,
                                          SourceRange Range) {
   QualType PointeeType = T->getPointeeType();
+  manglePointerCVQualifiers(Quals);
+  manglePointerExtQualifiers(Quals, PointeeType);
   if (const FunctionProtoType *FPT = PointeeType->getAs<FunctionProtoType>()) {
     Out << '8';
     mangleName(T->getClass()->castAs<RecordType>()->getDecl());
@@ -1848,7 +1946,7 @@ void MicrosoftCXXNameMangler::mangleType(const MemberPointerType *T,
 }
 
 void MicrosoftCXXNameMangler::mangleType(const TemplateTypeParmType *T,
-                                         SourceRange Range) {
+                                         Qualifiers, SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
     "cannot mangle this template type parameter type yet");
@@ -1856,9 +1954,8 @@ void MicrosoftCXXNameMangler::mangleType(const TemplateTypeParmType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(
-                                       const SubstTemplateTypeParmPackType *T,
-                                       SourceRange Range) {
+void MicrosoftCXXNameMangler::mangleType(const SubstTemplateTypeParmPackType *T,
+                                         Qualifiers, SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
     "cannot mangle this substituted parameter pack yet");
@@ -1869,40 +1966,46 @@ void MicrosoftCXXNameMangler::mangleType(
 // <type> ::= <pointer-type>
 // <pointer-type> ::= E? <pointer-cvr-qualifiers> <cvr-qualifiers> <type>
 //                       # the E is required for 64-bit non-static pointers
-void MicrosoftCXXNameMangler::mangleType(const PointerType *T,
+void MicrosoftCXXNameMangler::mangleType(const PointerType *T, Qualifiers Quals,
                                          SourceRange Range) {
-  QualType PointeeTy = T->getPointeeType();
-  mangleType(PointeeTy, Range);
+  QualType PointeeType = T->getPointeeType();
+  manglePointerCVQualifiers(Quals);
+  manglePointerExtQualifiers(Quals, PointeeType);
+  mangleType(PointeeType, Range);
 }
 void MicrosoftCXXNameMangler::mangleType(const ObjCObjectPointerType *T,
-                                         SourceRange Range) {
+                                         Qualifiers Quals, SourceRange Range) {
+  QualType PointeeType = T->getPointeeType();
+  manglePointerCVQualifiers(Quals);
+  manglePointerExtQualifiers(Quals, PointeeType);
   // Object pointers never have qualifiers.
   Out << 'A';
-  manglePointerExtQualifiers(Qualifiers(), T->getPointeeType().getTypePtr());
-  mangleType(T->getPointeeType(), Range);
+  mangleType(PointeeType, Range);
 }
 
 // <type> ::= <reference-type>
 // <reference-type> ::= A E? <cvr-qualifiers> <type>
 //                 # the E is required for 64-bit non-static lvalue references
 void MicrosoftCXXNameMangler::mangleType(const LValueReferenceType *T,
-                                         SourceRange Range) {
-  Out << 'A';
-  manglePointerExtQualifiers(Qualifiers(), T->getPointeeType().getTypePtr());
-  mangleType(T->getPointeeType(), Range);
+                                         Qualifiers Quals, SourceRange Range) {
+  QualType PointeeType = T->getPointeeType();
+  Out << (Quals.hasVolatile() ? 'B' : 'A');
+  manglePointerExtQualifiers(Quals, PointeeType);
+  mangleType(PointeeType, Range);
 }
 
 // <type> ::= <r-value-reference-type>
 // <r-value-reference-type> ::= $$Q E? <cvr-qualifiers> <type>
 //                 # the E is required for 64-bit non-static rvalue references
 void MicrosoftCXXNameMangler::mangleType(const RValueReferenceType *T,
-                                         SourceRange Range) {
-  Out << "$$Q";
-  manglePointerExtQualifiers(Qualifiers(), T->getPointeeType().getTypePtr());
-  mangleType(T->getPointeeType(), Range);
+                                         Qualifiers Quals, SourceRange Range) {
+  QualType PointeeType = T->getPointeeType();
+  Out << (Quals.hasVolatile() ? "$$R" : "$$Q");
+  manglePointerExtQualifiers(Quals, PointeeType);
+  mangleType(PointeeType, Range);
 }
 
-void MicrosoftCXXNameMangler::mangleType(const ComplexType *T,
+void MicrosoftCXXNameMangler::mangleType(const ComplexType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -1911,7 +2014,7 @@ void MicrosoftCXXNameMangler::mangleType(const ComplexType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const VectorType *T,
+void MicrosoftCXXNameMangler::mangleType(const VectorType *T, Qualifiers Quals,
                                          SourceRange Range) {
   const BuiltinType *ET = T->getElementType()->getAs<BuiltinType>();
   assert(ET && "vectors with non-builtin elements are unsupported");
@@ -1939,13 +2042,13 @@ void MicrosoftCXXNameMangler::mangleType(const VectorType *T,
     // our own mangling to handle uses of __vector_size__ on user-specified
     // types, and for extensions like __v4sf.
     Out << "T__clang_vec" << T->getNumElements() << '_';
-    mangleType(ET, Range);
+    mangleType(ET, Quals, Range);
   }
 
   Out << "@@";
 }
 
-void MicrosoftCXXNameMangler::mangleType(const ExtVectorType *T,
+void MicrosoftCXXNameMangler::mangleType(const ExtVectorType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -1954,7 +2057,7 @@ void MicrosoftCXXNameMangler::mangleType(const ExtVectorType *T,
     << Range;
 }
 void MicrosoftCXXNameMangler::mangleType(const DependentSizedExtVectorType *T,
-                                         SourceRange Range) {
+                                         Qualifiers, SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
     "cannot mangle this dependent-sized extended vector type yet");
@@ -1962,14 +2065,14 @@ void MicrosoftCXXNameMangler::mangleType(const DependentSizedExtVectorType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const ObjCInterfaceType *T,
+void MicrosoftCXXNameMangler::mangleType(const ObjCInterfaceType *T, Qualifiers,
                                          SourceRange) {
   // ObjC interfaces have structs underlying them.
   Out << 'U';
   mangleName(T->getDecl());
 }
 
-void MicrosoftCXXNameMangler::mangleType(const ObjCObjectType *T,
+void MicrosoftCXXNameMangler::mangleType(const ObjCObjectType *T, Qualifiers,
                                          SourceRange Range) {
   // We don't allow overloading by different protocol qualification,
   // so mangling them isn't necessary.
@@ -1977,20 +2080,23 @@ void MicrosoftCXXNameMangler::mangleType(const ObjCObjectType *T,
 }
 
 void MicrosoftCXXNameMangler::mangleType(const BlockPointerType *T,
-                                         SourceRange Range) {
+                                         Qualifiers Quals, SourceRange Range) {
+  QualType PointeeType = T->getPointeeType();
+  manglePointerCVQualifiers(Quals);
+  manglePointerExtQualifiers(Quals, PointeeType);
+
   Out << "_E";
 
-  QualType pointee = T->getPointeeType();
-  mangleFunctionType(pointee->castAs<FunctionProtoType>());
+  mangleFunctionType(PointeeType->castAs<FunctionProtoType>());
 }
 
 void MicrosoftCXXNameMangler::mangleType(const InjectedClassNameType *,
-                                         SourceRange) {
+                                         Qualifiers, SourceRange) {
   llvm_unreachable("Cannot mangle injected class name type.");
 }
 
 void MicrosoftCXXNameMangler::mangleType(const TemplateSpecializationType *T,
-                                         SourceRange Range) {
+                                         Qualifiers, SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
     "cannot mangle this template specialization type yet");
@@ -1998,7 +2104,7 @@ void MicrosoftCXXNameMangler::mangleType(const TemplateSpecializationType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const DependentNameType *T,
+void MicrosoftCXXNameMangler::mangleType(const DependentNameType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -2008,8 +2114,8 @@ void MicrosoftCXXNameMangler::mangleType(const DependentNameType *T,
 }
 
 void MicrosoftCXXNameMangler::mangleType(
-                                 const DependentTemplateSpecializationType *T,
-                                 SourceRange Range) {
+    const DependentTemplateSpecializationType *T, Qualifiers,
+    SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
     "cannot mangle this dependent template specialization type yet");
@@ -2017,7 +2123,7 @@ void MicrosoftCXXNameMangler::mangleType(
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const PackExpansionType *T,
+void MicrosoftCXXNameMangler::mangleType(const PackExpansionType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -2026,7 +2132,7 @@ void MicrosoftCXXNameMangler::mangleType(const PackExpansionType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const TypeOfType *T,
+void MicrosoftCXXNameMangler::mangleType(const TypeOfType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -2035,7 +2141,7 @@ void MicrosoftCXXNameMangler::mangleType(const TypeOfType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const TypeOfExprType *T,
+void MicrosoftCXXNameMangler::mangleType(const TypeOfExprType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -2044,7 +2150,7 @@ void MicrosoftCXXNameMangler::mangleType(const TypeOfExprType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const DecltypeType *T,
+void MicrosoftCXXNameMangler::mangleType(const DecltypeType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -2054,7 +2160,7 @@ void MicrosoftCXXNameMangler::mangleType(const DecltypeType *T,
 }
 
 void MicrosoftCXXNameMangler::mangleType(const UnaryTransformType *T,
-                                         SourceRange Range) {
+                                         Qualifiers, SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
     "cannot mangle this unary transform type yet");
@@ -2062,7 +2168,8 @@ void MicrosoftCXXNameMangler::mangleType(const UnaryTransformType *T,
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const AutoType *T, SourceRange Range) {
+void MicrosoftCXXNameMangler::mangleType(const AutoType *T, Qualifiers,
+                                         SourceRange Range) {
   assert(T->getDeducedType().isNull() && "expecting a dependent type!");
 
   DiagnosticsEngine &Diags = Context.getDiags();
@@ -2072,7 +2179,7 @@ void MicrosoftCXXNameMangler::mangleType(const AutoType *T, SourceRange Range) {
     << Range;
 }
 
-void MicrosoftCXXNameMangler::mangleType(const AtomicType *T,
+void MicrosoftCXXNameMangler::mangleType(const AtomicType *T, Qualifiers,
                                          SourceRange Range) {
   DiagnosticsEngine &Diags = Context.getDiags();
   unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
@@ -2273,6 +2380,74 @@ void MicrosoftMangleContextImpl::mangleCXXRTTIName(QualType T,
   Mangler.mangleType(T, SourceRange(), MicrosoftCXXNameMangler::QMM_Result);
 }
 
+void MicrosoftMangleContextImpl::mangleCXXCatchHandlerType(QualType T,
+                                                           uint32_t Flags,
+                                                           raw_ostream &Out) {
+  MicrosoftCXXNameMangler Mangler(*this, Out);
+  Mangler.getStream() << "llvm.eh.handlertype.";
+  Mangler.mangleType(T, SourceRange(), MicrosoftCXXNameMangler::QMM_Result);
+  Mangler.getStream() << '.' << Flags;
+}
+
+void MicrosoftMangleContextImpl::mangleCXXThrowInfo(QualType T,
+                                                    bool IsConst,
+                                                    bool IsVolatile,
+                                                    uint32_t NumEntries,
+                                                    raw_ostream &Out) {
+  MicrosoftCXXNameMangler Mangler(*this, Out);
+  Mangler.getStream() << "_TI";
+  if (IsConst)
+    Mangler.getStream() << 'C';
+  if (IsVolatile)
+    Mangler.getStream() << 'V';
+  Mangler.getStream() << NumEntries;
+  Mangler.mangleType(T, SourceRange(), MicrosoftCXXNameMangler::QMM_Result);
+}
+
+void MicrosoftMangleContextImpl::mangleCXXCatchableTypeArray(
+    QualType T, uint32_t NumEntries, raw_ostream &Out) {
+  MicrosoftCXXNameMangler Mangler(*this, Out);
+  Mangler.getStream() << "_CTA";
+  Mangler.getStream() << NumEntries;
+  Mangler.mangleType(T, SourceRange(), MicrosoftCXXNameMangler::QMM_Result);
+}
+
+void MicrosoftMangleContextImpl::mangleCXXCatchableType(
+    QualType T, const CXXConstructorDecl *CD, CXXCtorType CT, uint32_t Size,
+    uint32_t NVOffset, int32_t VBPtrOffset, uint32_t VBIndex,
+    raw_ostream &Out) {
+  MicrosoftCXXNameMangler Mangler(*this, Out);
+  Mangler.getStream() << "_CT";
+
+  llvm::SmallString<64> RTTIMangling;
+  {
+    llvm::raw_svector_ostream Stream(RTTIMangling);
+    mangleCXXRTTI(T, Stream);
+  }
+  Mangler.getStream() << RTTIMangling.substr(1);
+
+  // VS2015 CTP6 omits the copy-constructor in the mangled name.  This name is,
+  // in fact, superfluous but I'm not sure the change was made consciously.
+  // TODO: Revisit this when VS2015 gets released.
+  llvm::SmallString<64> CopyCtorMangling;
+  if (CD) {
+    llvm::raw_svector_ostream Stream(CopyCtorMangling);
+    mangleCXXCtor(CD, CT, Stream);
+  }
+  Mangler.getStream() << CopyCtorMangling.substr(1);
+
+  Mangler.getStream() << Size;
+  if (VBPtrOffset == -1) {
+    if (NVOffset) {
+      Mangler.getStream() << NVOffset;
+    }
+  } else {
+    Mangler.getStream() << NVOffset;
+    Mangler.getStream() << VBPtrOffset;
+    Mangler.getStream() << VBIndex;
+  }
+}
+
 void MicrosoftMangleContextImpl::mangleCXXRTTIBaseClassDescriptor(
     const CXXRecordDecl *Derived, uint32_t NVOffset, int32_t VBPtrOffset,
     uint32_t VBTableOffset, uint32_t Flags, raw_ostream &Out) {
@@ -2318,6 +2493,28 @@ void MicrosoftMangleContextImpl::mangleCXXRTTICompleteObjectLocator(
   Mangler.getStream() << '@';
 }
 
+void MicrosoftMangleContextImpl::mangleSEHFilterExpression(
+    const NamedDecl *EnclosingDecl, raw_ostream &Out) {
+  MicrosoftCXXNameMangler Mangler(*this, Out);
+  // The function body is in the same comdat as the function with the handler,
+  // so the numbering here doesn't have to be the same across TUs.
+  //
+  // <mangled-name> ::= ?filt$ <filter-number> @0
+  Mangler.getStream() << "\01?filt$" << SEHFilterIds[EnclosingDecl]++ << "@0@";
+  Mangler.mangleName(EnclosingDecl);
+}
+
+void MicrosoftMangleContextImpl::mangleSEHFinallyBlock(
+    const NamedDecl *EnclosingDecl, raw_ostream &Out) {
+  MicrosoftCXXNameMangler Mangler(*this, Out);
+  // The function body is in the same comdat as the function with the handler,
+  // so the numbering here doesn't have to be the same across TUs.
+  //
+  // <mangled-name> ::= ?fin$ <filter-number> @0
+  Mangler.getStream() << "\01?fin$" << SEHFinallyIds[EnclosingDecl]++ << "@0@";
+  Mangler.mangleName(EnclosingDecl);
+}
+
 void MicrosoftMangleContextImpl::mangleTypeName(QualType T, raw_ostream &Out) {
   // This is just a made up unique string for the purposes of tbaa.  undname
   // does *not* know how to demangle it.
@@ -2329,7 +2526,7 @@ void MicrosoftMangleContextImpl::mangleTypeName(QualType T, raw_ostream &Out) {
 void MicrosoftMangleContextImpl::mangleCXXCtor(const CXXConstructorDecl *D,
                                                CXXCtorType Type,
                                                raw_ostream &Out) {
-  MicrosoftCXXNameMangler mangler(*this, Out);
+  MicrosoftCXXNameMangler mangler(*this, Out, D, Type);
   mangler.mangle(D);
 }
 
@@ -2348,18 +2545,18 @@ void MicrosoftMangleContextImpl::mangleReferenceTemporary(const VarDecl *VD,
   getDiags().Report(VD->getLocation(), DiagID);
 }
 
+void MicrosoftMangleContextImpl::mangleThreadSafeStaticGuardVariable(
+    const VarDecl *VD, unsigned GuardNum, raw_ostream &Out) {
+  MicrosoftCXXNameMangler Mangler(*this, Out);
+
+  Mangler.getStream() << "\01?$TSS" << GuardNum << '@';
+  Mangler.mangleNestedName(VD);
+}
+
 void MicrosoftMangleContextImpl::mangleStaticGuardVariable(const VarDecl *VD,
                                                            raw_ostream &Out) {
-  // TODO: This is not correct, especially with respect to VS "14".  VS "14"
-  // utilizes thread local variables to implement thread safe, re-entrant
-  // initialization for statics.  They no longer differentiate between an
-  // externally visible and non-externally visible static with respect to
-  // mangling, they all get $TSS <number>.
-  //
-  // N.B. This means that they can get more than 32 static variable guards in a
-  // scope.  It also means that they broke compatibility with their own ABI.
-
   // <guard-name> ::= ?_B <postfix> @5 <scope-depth>
+  //              ::= ?__J <postfix> @5 <scope-depth>
   //              ::= ?$S <guard-num> @ <postfix> @4IA
 
   // The first mangling is what MSVC uses to guard static locals in inline
@@ -2371,8 +2568,11 @@ void MicrosoftMangleContextImpl::mangleStaticGuardVariable(const VarDecl *VD,
   MicrosoftCXXNameMangler Mangler(*this, Out);
 
   bool Visible = VD->isExternallyVisible();
-  // <operator-name> ::= ?_B # local static guard
-  Mangler.getStream() << (Visible ? "\01??_B" : "\01?$S1@");
+  if (Visible) {
+    Mangler.getStream() << (VD->getTLSKind() ? "\01??__J" : "\01??_B");
+  } else {
+    Mangler.getStream() << "\01?$S1@";
+  }
   unsigned ScopeDepth = 0;
   if (Visible && !getNextDiscriminator(VD, ScopeDepth))
     // If we do not have a discriminator and are emitting a guard variable for
@@ -2553,6 +2753,11 @@ void MicrosoftMangleContextImpl::mangleStringLiteral(const StringLiteral *SL,
   Mangler.getStream() << '@';
 }
 
+void MicrosoftMangleContextImpl::mangleCXXVTableBitSet(const CXXRecordDecl *RD,
+                                                       raw_ostream &Out) {
+  llvm::report_fatal_error("Cannot mangle bitsets yet");
+}
+
 MicrosoftMangleContext *
 MicrosoftMangleContext::create(ASTContext &Context, DiagnosticsEngine &Diags) {
   return new MicrosoftMangleContextImpl(Context, Diags);
diff --git a/lib/AST/NSAPI.cpp b/lib/AST/NSAPI.cpp
index 3dc750a81787..2749100e14a2 100644
--- a/lib/AST/NSAPI.cpp
+++ b/lib/AST/NSAPI.cpp
@@ -27,7 +27,10 @@ IdentifierInfo *NSAPI::getNSClassId(NSClassIdKindKind K) const {
     "NSMutableArray",
     "NSDictionary",
     "NSMutableDictionary",
-    "NSNumber"
+    "NSNumber",
+    "NSMutableSet",
+    "NSCountedSet",
+    "NSMutableOrderedSet"
   };
 
   if (!ClassIds[K])
@@ -124,6 +127,25 @@ Selector NSAPI::getNSArraySelector(NSArrayMethodKind MK) const {
       Sel = Ctx.Selectors.getSelector(2, KeyIdents);
       break;
     }
+    case NSMutableArr_addObject:
+      Sel = Ctx.Selectors.getUnarySelector(&Ctx.Idents.get("addObject"));
+      break;
+    case NSMutableArr_insertObjectAtIndex: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("insertObject"),
+        &Ctx.Idents.get("atIndex")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
+    case NSMutableArr_setObjectAtIndexedSubscript: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("setObject"),
+        &Ctx.Idents.get("atIndexedSubscript")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
     }
     return (NSArraySelectors[MK] = Sel);
   }
@@ -209,6 +231,22 @@ Selector NSAPI::getNSDictionarySelector(
       Sel = Ctx.Selectors.getSelector(2, KeyIdents);
       break;
     }
+    case NSMutableDict_setObjectForKeyedSubscript: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("setObject"),
+        &Ctx.Idents.get("forKeyedSubscript")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
+    case NSMutableDict_setValueForKey: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("setValue"),
+        &Ctx.Idents.get("forKey")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
     }
     return (NSDictionarySelectors[MK] = Sel);
   }
@@ -227,6 +265,63 @@ NSAPI::getNSDictionaryMethodKind(Selector Sel) {
   return None;
 }
 
+Selector NSAPI::getNSSetSelector(NSSetMethodKind MK) const {
+  if (NSSetSelectors[MK].isNull()) {
+    Selector Sel;
+    switch (MK) {
+    case NSMutableSet_addObject:
+      Sel = Ctx.Selectors.getUnarySelector(&Ctx.Idents.get("addObject"));
+      break;
+    case NSOrderedSet_insertObjectAtIndex: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("insertObject"),
+        &Ctx.Idents.get("atIndex")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
+    case NSOrderedSet_setObjectAtIndex: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("setObject"),
+        &Ctx.Idents.get("atIndex")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
+    case NSOrderedSet_setObjectAtIndexedSubscript: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("setObject"),
+        &Ctx.Idents.get("atIndexedSubscript")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
+    case NSOrderedSet_replaceObjectAtIndexWithObject: {
+      IdentifierInfo *KeyIdents[] = {
+        &Ctx.Idents.get("replaceObjectAtIndex"),
+        &Ctx.Idents.get("withObject")
+      };
+      Sel = Ctx.Selectors.getSelector(2, KeyIdents);
+      break;
+    }
+    }
+    return (NSSetSelectors[MK] = Sel);
+  }
+
+  return NSSetSelectors[MK];
+}
+
+Optional<NSAPI::NSSetMethodKind>
+NSAPI::getNSSetMethodKind(Selector Sel) {
+  for (unsigned i = 0; i != NumNSSetMethods; ++i) {
+    NSSetMethodKind MK = NSSetMethodKind(i);
+    if (Sel == getNSSetSelector(MK))
+      return MK;
+  }
+
+  return None;
+}
+
 Selector NSAPI::getNSNumberLiteralSelector(NSNumberLiteralMethodKind MK,
                                            bool Instance) const {
   static const char *ClassSelectorName[NumNSNumberLiteralMethods] = {
@@ -410,6 +505,11 @@ StringRef NSAPI::GetNSIntegralKind(QualType T) const {
   return StringRef();
 }
 
+bool NSAPI::isMacroDefined(StringRef Id) const {
+  // FIXME: Check whether the relevant module macros are visible.
+  return Ctx.Idents.get(Id).hasMacroDefinition();
+}
+
 bool NSAPI::isObjCTypedef(QualType T,
                           StringRef name, IdentifierInfo *&II) const {
   if (!Ctx.getLangOpts().ObjC1)
diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp
index 0d070a4bfbfc..2101a5534a6b 100644
--- a/lib/AST/RecordLayoutBuilder.cpp
+++ b/lib/AST/RecordLayoutBuilder.cpp
@@ -55,6 +55,52 @@ struct BaseSubobjectInfo {
   const BaseSubobjectInfo *Derived;
 };
 
+/// \brief Externally provided layout. Typically used when the AST source, such
+/// as DWARF, lacks all the information that was available at compile time, such
+/// as alignment attributes on fields and pragmas in effect.
+struct ExternalLayout {
+  ExternalLayout() : Size(0), Align(0) {}
+
+  /// \brief Overall record size in bits.
+  uint64_t Size;
+
+  /// \brief Overall record alignment in bits.
+  uint64_t Align;
+
+  /// \brief Record field offsets in bits.
+  llvm::DenseMap<const FieldDecl *, uint64_t> FieldOffsets;
+
+  /// \brief Direct, non-virtual base offsets.
+  llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsets;
+
+  /// \brief Virtual base offsets.
+  llvm::DenseMap<const CXXRecordDecl *, CharUnits> VirtualBaseOffsets;
+
+  /// Get the offset of the given field. The external source must provide
+  /// entries for all fields in the record.
+  uint64_t getExternalFieldOffset(const FieldDecl *FD) {
+    assert(FieldOffsets.count(FD) &&
+           "Field does not have an external offset");
+    return FieldOffsets[FD];
+  }
+
+  bool getExternalNVBaseOffset(const CXXRecordDecl *RD, CharUnits &BaseOffset) {
+    auto Known = BaseOffsets.find(RD);
+    if (Known == BaseOffsets.end())
+      return false;
+    BaseOffset = Known->second;
+    return true;
+  }
+
+  bool getExternalVBaseOffset(const CXXRecordDecl *RD, CharUnits &BaseOffset) {
+    auto Known = VirtualBaseOffsets.find(RD);
+    if (Known == VirtualBaseOffsets.end())
+      return false;
+    BaseOffset = Known->second;
+    return true;
+  }
+};
+
 /// EmptySubobjectMap - Keeps track of which empty subobjects exist at different
 /// offsets while laying out a C++ class.
 class EmptySubobjectMap {
@@ -541,7 +587,7 @@ protected:
 
   /// \brief Whether the external AST source has provided a layout for this
   /// record.
-  unsigned ExternalLayout : 1;
+  unsigned UseExternalLayout : 1;
 
   /// \brief Whether we need to infer alignment, even when we have an 
   /// externally-provided layout.
@@ -607,26 +653,14 @@ protected:
   /// avoid visiting virtual bases more than once.
   llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBases;
 
-  /// \brief Externally-provided size.
-  uint64_t ExternalSize;
-  
-  /// \brief Externally-provided alignment.
-  uint64_t ExternalAlign;
-  
-  /// \brief Externally-provided field offsets.
-  llvm::DenseMap<const FieldDecl *, uint64_t> ExternalFieldOffsets;
-
-  /// \brief Externally-provided direct, non-virtual base offsets.
-  llvm::DenseMap<const CXXRecordDecl *, CharUnits> ExternalBaseOffsets;
-
-  /// \brief Externally-provided virtual base offsets.
-  llvm::DenseMap<const CXXRecordDecl *, CharUnits> ExternalVirtualBaseOffsets;
+  /// Valid if UseExternalLayout is true.
+  ExternalLayout External;
 
   RecordLayoutBuilder(const ASTContext &Context,
                       EmptySubobjectMap *EmptySubobjects)
     : Context(Context), EmptySubobjects(EmptySubobjects), Size(0), 
       Alignment(CharUnits::One()), UnpackedAlignment(CharUnits::One()),
-      ExternalLayout(false), InferAlignment(false), 
+      UseExternalLayout(false), InferAlignment(false),
       Packed(false), IsUnion(false), IsMac68kAlign(false), IsMsStruct(false),
       UnfilledBitsInLastUnit(0), LastBitfieldTypeSize(0),
       MaxFieldAlignment(CharUnits::Zero()), 
@@ -748,8 +782,8 @@ protected:
   void setDataSize(CharUnits NewSize) { DataSize = Context.toBits(NewSize); }
   void setDataSize(uint64_t NewSize) { DataSize = NewSize; }
 
-  RecordLayoutBuilder(const RecordLayoutBuilder &) LLVM_DELETED_FUNCTION;
-  void operator=(const RecordLayoutBuilder &) LLVM_DELETED_FUNCTION;
+  RecordLayoutBuilder(const RecordLayoutBuilder &) = delete;
+  void operator=(const RecordLayoutBuilder &) = delete;
 };
 } // end anonymous namespace
 
@@ -1134,21 +1168,12 @@ CharUnits RecordLayoutBuilder::LayoutBase(const BaseSubobjectInfo *Base) {
   
   // Query the external layout to see if it provides an offset.
   bool HasExternalLayout = false;
-  if (ExternalLayout) {
+  if (UseExternalLayout) {
     llvm::DenseMap<const CXXRecordDecl *, CharUnits>::iterator Known;
-    if (Base->IsVirtual) {
-      Known = ExternalVirtualBaseOffsets.find(Base->Class);
-      if (Known != ExternalVirtualBaseOffsets.end()) {
-        Offset = Known->second;
-        HasExternalLayout = true;
-      }
-    } else {
-      Known = ExternalBaseOffsets.find(Base->Class);
-      if (Known != ExternalBaseOffsets.end()) {
-        Offset = Known->second;
-        HasExternalLayout = true;
-      }
-    }
+    if (Base->IsVirtual)
+      HasExternalLayout = External.getExternalNVBaseOffset(Base->Class, Offset);
+    else
+      HasExternalLayout = External.getExternalVBaseOffset(Base->Class, Offset);
   }
   
   CharUnits UnpackedBaseAlign = Layout.getNonVirtualAlignment();
@@ -1235,18 +1260,15 @@ void RecordLayoutBuilder::InitializeLayout(const Decl *D) {
   
   // If there is an external AST source, ask it for the various offsets.
   if (const RecordDecl *RD = dyn_cast<RecordDecl>(D))
-    if (ExternalASTSource *External = Context.getExternalSource()) {
-      ExternalLayout = External->layoutRecordType(RD, 
-                                                  ExternalSize,
-                                                  ExternalAlign,
-                                                  ExternalFieldOffsets,
-                                                  ExternalBaseOffsets,
-                                                  ExternalVirtualBaseOffsets);
-      
+    if (ExternalASTSource *Source = Context.getExternalSource()) {
+      UseExternalLayout = Source->layoutRecordType(
+          RD, External.Size, External.Align, External.FieldOffsets,
+          External.BaseOffsets, External.VirtualBaseOffsets);
+
       // Update based on external alignment.
-      if (ExternalLayout) {
-        if (ExternalAlign > 0) {
-          Alignment = Context.toCharUnitsFromBits(ExternalAlign);
+      if (UseExternalLayout) {
+        if (External.Align > 0) {
+          Alignment = Context.toCharUnitsFromBits(External.Align);
         } else {
           // The external source didn't have alignment information; infer it.
           InferAlignment = true;
@@ -1588,7 +1610,7 @@ void RecordLayoutBuilder::LayoutBitField(const FieldDecl *D) {
 
   // If we're using external layout, give the external layout a chance
   // to override this information.
-  if (ExternalLayout)
+  if (UseExternalLayout)
     FieldOffset = updateExternalFieldOffset(D, FieldOffset);
 
   // Okay, place the bitfield at the calculated offset.
@@ -1604,7 +1626,7 @@ void RecordLayoutBuilder::LayoutBitField(const FieldDecl *D) {
     FieldAlign = UnpackedFieldAlign = 1;
 
   // Diagnose differences in layout due to padding or packing.
-  if (!ExternalLayout)
+  if (!UseExternalLayout)
     CheckFieldPadding(FieldOffset, UnpaddedFieldOffset, UnpackedFieldOffset,
                       UnpackedFieldAlign, FieldPacked, D);
 
@@ -1727,7 +1749,7 @@ void RecordLayoutBuilder::LayoutField(const FieldDecl *D,
   UnpackedFieldOffset = 
     UnpackedFieldOffset.RoundUpToAlignment(UnpackedFieldAlign);
 
-  if (ExternalLayout) {
+  if (UseExternalLayout) {
     FieldOffset = Context.toCharUnitsFromBits(
                     updateExternalFieldOffset(D, Context.toBits(FieldOffset)));
     
@@ -1750,7 +1772,7 @@ void RecordLayoutBuilder::LayoutField(const FieldDecl *D,
   // Place this field at the current location.
   FieldOffsets.push_back(Context.toBits(FieldOffset));
 
-  if (!ExternalLayout)
+  if (!UseExternalLayout)
     CheckFieldPadding(Context.toBits(FieldOffset), UnpaddedFieldOffset, 
                       Context.toBits(UnpackedFieldOffset),
                       Context.toBits(UnpackedFieldAlign), FieldPacked, D);
@@ -1802,15 +1824,15 @@ void RecordLayoutBuilder::FinishLayout(const NamedDecl *D) {
   uint64_t RoundedSize
     = llvm::RoundUpToAlignment(getSizeInBits(), Context.toBits(Alignment));
 
-  if (ExternalLayout) {
+  if (UseExternalLayout) {
     // If we're inferring alignment, and the external size is smaller than
     // our size after we've rounded up to alignment, conservatively set the
     // alignment to 1.
-    if (InferAlignment && ExternalSize < RoundedSize) {
+    if (InferAlignment && External.Size < RoundedSize) {
       Alignment = CharUnits::One();
       InferAlignment = false;
     }
-    setSize(ExternalSize);
+    setSize(External.Size);
     return;
   }
 
@@ -1846,18 +1868,18 @@ void RecordLayoutBuilder::UpdateAlignment(CharUnits NewAlignment,
                                           CharUnits UnpackedNewAlignment) {
   // The alignment is not modified when using 'mac68k' alignment or when
   // we have an externally-supplied layout that also provides overall alignment.
-  if (IsMac68kAlign || (ExternalLayout && !InferAlignment))
+  if (IsMac68kAlign || (UseExternalLayout && !InferAlignment))
     return;
 
   if (NewAlignment > Alignment) {
-    assert(llvm::isPowerOf2_32(NewAlignment.getQuantity() && 
-           "Alignment not a power of 2"));
+    assert(llvm::isPowerOf2_64(NewAlignment.getQuantity()) &&
+           "Alignment not a power of 2");
     Alignment = NewAlignment;
   }
 
   if (UnpackedNewAlignment > UnpackedAlignment) {
-    assert(llvm::isPowerOf2_32(UnpackedNewAlignment.getQuantity() &&
-           "Alignment not a power of 2"));
+    assert(llvm::isPowerOf2_64(UnpackedNewAlignment.getQuantity()) &&
+           "Alignment not a power of 2");
     UnpackedAlignment = UnpackedNewAlignment;
   }
 }
@@ -1865,11 +1887,8 @@ void RecordLayoutBuilder::UpdateAlignment(CharUnits NewAlignment,
 uint64_t
 RecordLayoutBuilder::updateExternalFieldOffset(const FieldDecl *Field, 
                                                uint64_t ComputedOffset) {
-  assert(ExternalFieldOffsets.find(Field) != ExternalFieldOffsets.end() &&
-         "Field does not have an external offset");
-  
-  uint64_t ExternalFieldOffset = ExternalFieldOffsets[Field];
-  
+  uint64_t ExternalFieldOffset = External.getExternalFieldOffset(Field);
+
   if (InferAlignment && ExternalFieldOffset < ComputedOffset) {
     // The externally-supplied field offset is before the field offset we
     // computed. Assume that the structure is packed.
@@ -2152,9 +2171,8 @@ struct MicrosoftRecordLayoutBuilder {
   typedef llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsetsMapTy;
   MicrosoftRecordLayoutBuilder(const ASTContext &Context) : Context(Context) {}
 private:
-  MicrosoftRecordLayoutBuilder(const MicrosoftRecordLayoutBuilder &)
-  LLVM_DELETED_FUNCTION;
-  void operator=(const MicrosoftRecordLayoutBuilder &) LLVM_DELETED_FUNCTION;
+  MicrosoftRecordLayoutBuilder(const MicrosoftRecordLayoutBuilder &) = delete;
+  void operator=(const MicrosoftRecordLayoutBuilder &) = delete;
 public:
   void layout(const RecordDecl *RD);
   void cxxLayout(const CXXRecordDecl *RD);
@@ -2252,6 +2270,13 @@ public:
   /// \brief True if this class is zero sized or first base is zero sized or
   /// has this property.  Only used for MS-ABI.
   bool LeadsWithZeroSizedBase : 1;
+
+  /// \brief True if the external AST source provided a layout for this record.
+  bool UseExternalLayout : 1;
+
+  /// \brief The layout provided by the external AST source. Only active if
+  /// UseExternalLayout is true.
+  ExternalLayout External;
 };
 } // namespace
 
@@ -2354,8 +2379,9 @@ void MicrosoftRecordLayoutBuilder::initializeLayout(const RecordDecl *RD) {
   // In 64-bit mode we always perform an alignment step after laying out vbases.
   // In 32-bit mode we do not.  The check to see if we need to perform alignment
   // checks the RequiredAlignment field and performs alignment if it isn't 0.
-  RequiredAlignment = Context.getTargetInfo().getPointerWidth(0) == 64 ?
-                      CharUnits::One() : CharUnits::Zero();
+  RequiredAlignment = Context.getTargetInfo().getTriple().isArch64Bit()
+                          ? CharUnits::One()
+                          : CharUnits::Zero();
   // Compute the maximum field alignment.
   MaxFieldAlignment = CharUnits::Zero();
   // Honor the default struct packing maximum alignment flag.
@@ -2371,6 +2397,13 @@ void MicrosoftRecordLayoutBuilder::initializeLayout(const RecordDecl *RD) {
   // Packed attribute forces max field alignment to be 1.
   if (RD->hasAttr<PackedAttr>())
     MaxFieldAlignment = CharUnits::One();
+
+  // Try to respect the external layout if present.
+  UseExternalLayout = false;
+  if (ExternalASTSource *Source = Context.getExternalSource())
+    UseExternalLayout = Source->layoutRecordType(
+        RD, External.Size, External.Align, External.FieldOffsets,
+        External.BaseOffsets, External.VirtualBaseOffsets);
 }
 
 void
@@ -2385,7 +2418,8 @@ MicrosoftRecordLayoutBuilder::initializeCXXLayout(const CXXRecordDecl *RD) {
   // injection.
   PointerInfo.Size =
       Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
-  PointerInfo.Alignment = PointerInfo.Size;
+  PointerInfo.Alignment =
+      Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerAlign(0));
   // Respect pragma pack.
   if (!MaxFieldAlignment.isZero())
     PointerInfo.Alignment = std::min(PointerInfo.Alignment, MaxFieldAlignment);
@@ -2475,7 +2509,18 @@ void MicrosoftRecordLayoutBuilder::layoutNonVirtualBase(
       BaseLayout.leadsWithZeroSizedBase())
     Size++;
   ElementInfo Info = getAdjustedElementInfo(BaseLayout);
-  CharUnits BaseOffset = Size.RoundUpToAlignment(Info.Alignment);
+  CharUnits BaseOffset;
+
+  // Respect the external AST source base offset, if present.
+  bool FoundBase = false;
+  if (UseExternalLayout) {
+    FoundBase = External.getExternalNVBaseOffset(BaseDecl, BaseOffset);
+    if (FoundBase)
+      assert(BaseOffset >= Size && "base offset already allocated");
+  }
+
+  if (!FoundBase)
+    BaseOffset = Size.RoundUpToAlignment(Info.Alignment);
   Bases.insert(std::make_pair(BaseDecl, BaseOffset));
   Size = BaseOffset + BaseLayout.getNonVirtualSize();
   PreviousBaseLayout = &BaseLayout;
@@ -2499,7 +2544,14 @@ void MicrosoftRecordLayoutBuilder::layoutField(const FieldDecl *FD) {
     placeFieldAtOffset(CharUnits::Zero());
     Size = std::max(Size, Info.Size);
   } else {
-    CharUnits FieldOffset = Size.RoundUpToAlignment(Info.Alignment);
+    CharUnits FieldOffset;
+    if (UseExternalLayout) {
+      FieldOffset =
+          Context.toCharUnitsFromBits(External.getExternalFieldOffset(FD));
+      assert(FieldOffset >= Size && "field offset already allocated");
+    } else {
+      FieldOffset = Size.RoundUpToAlignment(Info.Alignment);
+    }
     placeFieldAtOffset(FieldOffset);
     Size = FieldOffset + Info.Size;
   }
@@ -2573,14 +2625,16 @@ void MicrosoftRecordLayoutBuilder::injectVBPtr(const CXXRecordDecl *RD) {
   CharUnits InjectionSite = VBPtrOffset;
   // But before we do, make sure it's properly aligned.
   VBPtrOffset = VBPtrOffset.RoundUpToAlignment(PointerInfo.Alignment);
+  // Shift everything after the vbptr down, unless we're using an external
+  // layout.
+  if (UseExternalLayout)
+    return;
   // Determine where the first field should be laid out after the vbptr.
   CharUnits FieldStart = VBPtrOffset + PointerInfo.Size;
   // Make sure that the amount we push the fields back by is a multiple of the
   // alignment.
   CharUnits Offset = (FieldStart - InjectionSite).RoundUpToAlignment(
       std::max(RequiredAlignment, Alignment));
-  // Increase the size of the object and push back all fields by the offset
-  // amount.
   Size += Offset;
   for (uint64_t &FieldOffset : FieldOffsets)
     FieldOffset += Context.toBits(Offset);
@@ -2647,7 +2701,18 @@ void MicrosoftRecordLayoutBuilder::layoutVirtualBases(const CXXRecordDecl *RD) {
     }
     // Insert the virtual base.
     ElementInfo Info = getAdjustedElementInfo(BaseLayout);
-    CharUnits BaseOffset = Size.RoundUpToAlignment(Info.Alignment);
+    CharUnits BaseOffset;
+
+    // Respect the external AST source base offset, if present.
+    bool FoundBase = false;
+    if (UseExternalLayout) {
+      FoundBase = External.getExternalVBaseOffset(BaseDecl, BaseOffset);
+      if (FoundBase)
+        assert(BaseOffset >= Size && "base offset already allocated");
+    }
+    if (!FoundBase)
+      BaseOffset = Size.RoundUpToAlignment(Info.Alignment);
+
     VBases.insert(std::make_pair(BaseDecl,
         ASTRecordLayout::VBaseInfo(BaseOffset, HasVtordisp)));
     Size = BaseOffset + BaseLayout.getNonVirtualSize();
@@ -2677,6 +2742,12 @@ void MicrosoftRecordLayoutBuilder::finalizeLayout(const RecordDecl *RD) {
     else
       Size = MinEmptyStructSize;
   }
+
+  if (UseExternalLayout) {
+    Size = Context.toCharUnitsFromBits(External.Size);
+    if (External.Align)
+      Alignment = Context.toCharUnitsFromBits(External.Align);
+  }
 }
 
 // Recursively walks the non-virtual bases of a class and determines if any of
@@ -2815,7 +2886,7 @@ ASTContext::getASTRecordLayout(const RecordDecl *D) const {
 
   const ASTRecordLayout *NewEntry = nullptr;
 
-  if (isMsLayout(D) && !D->getASTContext().getExternalSource()) {
+  if (isMsLayout(D)) {
     NewEntry = BuildMicrosoftASTRecordLayout(D);
   } else if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
     EmptySubobjectMap EmptySubobjects(*this, RD);
@@ -2905,11 +2976,11 @@ void ASTContext::setNonKeyFunction(const CXXMethodDecl *Method) {
   // Look up the cache entry.  Since we're working with the first
   // declaration, its parent must be the class definition, which is
   // the correct key for the KeyFunctions hash.
-  llvm::DenseMap<const CXXRecordDecl*, LazyDeclPtr>::iterator
-    I = KeyFunctions.find(Method->getParent());
+  const auto &Map = KeyFunctions;
+  auto I = Map.find(Method->getParent());
 
   // If it's not cached, there's nothing to do.
-  if (I == KeyFunctions.end()) return;
+  if (I == Map.end()) return;
 
   // If it is cached, check whether it's the target method, and if so,
   // remove it from the cache. Note, the call to 'get' might invalidate
diff --git a/lib/AST/Stmt.cpp b/lib/AST/Stmt.cpp
index 68c7e7278432..6baa99bbc5bf 100644
--- a/lib/AST/Stmt.cpp
+++ b/lib/AST/Stmt.cpp
@@ -95,10 +95,16 @@ void Stmt::EnableStatistics() {
 Stmt *Stmt::IgnoreImplicit() {
   Stmt *s = this;
 
-  if (ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(s))
+  if (auto *ewc = dyn_cast<ExprWithCleanups>(s))
     s = ewc->getSubExpr();
 
-  while (ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(s))
+  if (auto *mte = dyn_cast<MaterializeTemporaryExpr>(s))
+    s = mte->GetTemporaryExpr();
+
+  if (auto *bte = dyn_cast<CXXBindTemporaryExpr>(s))
+    s = bte->getSubExpr();
+
+  while (auto *ice = dyn_cast<ImplicitCastExpr>(s))
     s = ice->getSubExpr();
 
   return s;
@@ -934,8 +940,7 @@ void ForStmt::setConditionVariable(const ASTContext &C, VarDecl *V) {
 }
 
 SwitchStmt::SwitchStmt(const ASTContext &C, VarDecl *Var, Expr *cond)
-  : Stmt(SwitchStmtClass), FirstCase(nullptr), AllEnumCasesCovered(0)
-{
+    : Stmt(SwitchStmtClass), FirstCase(nullptr, false) {
   setConditionVariable(C, Var);
   SubExprs[COND] = cond;
   SubExprs[BODY] = nullptr;
@@ -1241,17 +1246,47 @@ OMPFirstprivateClause *OMPFirstprivateClause::CreateEmpty(const ASTContext &C,
   return new (Mem) OMPFirstprivateClause(N);
 }
 
-OMPLastprivateClause *OMPLastprivateClause::Create(const ASTContext &C,
-                                                   SourceLocation StartLoc,
-                                                   SourceLocation LParenLoc,
-                                                   SourceLocation EndLoc,
-                                                   ArrayRef<Expr *> VL) {
+void OMPLastprivateClause::setPrivateCopies(ArrayRef<Expr *> PrivateCopies) {
+  assert(PrivateCopies.size() == varlist_size() &&
+         "Number of private copies is not the same as the preallocated buffer");
+  std::copy(PrivateCopies.begin(), PrivateCopies.end(), varlist_end());
+}
+
+void OMPLastprivateClause::setSourceExprs(ArrayRef<Expr *> SrcExprs) {
+  assert(SrcExprs.size() == varlist_size() && "Number of source expressions is "
+                                              "not the same as the "
+                                              "preallocated buffer");
+  std::copy(SrcExprs.begin(), SrcExprs.end(), getPrivateCopies().end());
+}
+
+void OMPLastprivateClause::setDestinationExprs(ArrayRef<Expr *> DstExprs) {
+  assert(DstExprs.size() == varlist_size() && "Number of destination "
+                                              "expressions is not the same as "
+                                              "the preallocated buffer");
+  std::copy(DstExprs.begin(), DstExprs.end(), getSourceExprs().end());
+}
+
+void OMPLastprivateClause::setAssignmentOps(ArrayRef<Expr *> AssignmentOps) {
+  assert(AssignmentOps.size() == varlist_size() &&
+         "Number of assignment expressions is not the same as the preallocated "
+         "buffer");
+  std::copy(AssignmentOps.begin(), AssignmentOps.end(),
+            getDestinationExprs().end());
+}
+
+OMPLastprivateClause *OMPLastprivateClause::Create(
+    const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
+    SourceLocation EndLoc, ArrayRef<Expr *> VL, ArrayRef<Expr *> SrcExprs,
+    ArrayRef<Expr *> DstExprs, ArrayRef<Expr *> AssignmentOps) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPLastprivateClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * VL.size());
+                         5 * sizeof(Expr *) * VL.size());
   OMPLastprivateClause *Clause =
       new (Mem) OMPLastprivateClause(StartLoc, LParenLoc, EndLoc, VL.size());
   Clause->setVarRefs(VL);
+  Clause->setSourceExprs(SrcExprs);
+  Clause->setDestinationExprs(DstExprs);
+  Clause->setAssignmentOps(AssignmentOps);
   return Clause;
 }
 
@@ -1259,7 +1294,7 @@ OMPLastprivateClause *OMPLastprivateClause::CreateEmpty(const ASTContext &C,
                                                         unsigned N) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPLastprivateClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * N);
+                         5 * sizeof(Expr *) * N);
   return new (Mem) OMPLastprivateClause(N);
 }
 
@@ -1285,27 +1320,56 @@ OMPSharedClause *OMPSharedClause::CreateEmpty(const ASTContext &C,
   return new (Mem) OMPSharedClause(N);
 }
 
-OMPLinearClause *OMPLinearClause::Create(const ASTContext &C,
-                                         SourceLocation StartLoc,
-                                         SourceLocation LParenLoc,
-                                         SourceLocation ColonLoc,
-                                         SourceLocation EndLoc,
-                                         ArrayRef<Expr *> VL, Expr *Step) {
+void OMPLinearClause::setInits(ArrayRef<Expr *> IL) {
+  assert(IL.size() == varlist_size() &&
+         "Number of inits is not the same as the preallocated buffer");
+  std::copy(IL.begin(), IL.end(), varlist_end());
+}
+
+void OMPLinearClause::setUpdates(ArrayRef<Expr *> UL) {
+  assert(UL.size() == varlist_size() &&
+         "Number of updates is not the same as the preallocated buffer");
+  std::copy(UL.begin(), UL.end(), getInits().end());
+}
+
+void OMPLinearClause::setFinals(ArrayRef<Expr *> FL) {
+  assert(FL.size() == varlist_size() &&
+         "Number of final updates is not the same as the preallocated buffer");
+  std::copy(FL.begin(), FL.end(), getUpdates().end());
+}
+
+OMPLinearClause *
+OMPLinearClause::Create(const ASTContext &C, SourceLocation StartLoc,
+                        SourceLocation LParenLoc, SourceLocation ColonLoc,
+                        SourceLocation EndLoc, ArrayRef<Expr *> VL,
+                        ArrayRef<Expr *> IL, Expr *Step, Expr *CalcStep) {
+  // Allocate space for 4 lists (Vars, Inits, Updates, Finals) and 2 expressions
+  // (Step and CalcStep).
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPLinearClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * (VL.size() + 1));
+                         (4 * VL.size() + 2) * sizeof(Expr *));
   OMPLinearClause *Clause = new (Mem)
       OMPLinearClause(StartLoc, LParenLoc, ColonLoc, EndLoc, VL.size());
   Clause->setVarRefs(VL);
+  Clause->setInits(IL);
+  // Fill update and final expressions with zeroes, they are provided later,
+  // after the directive construction.
+  std::fill(Clause->getInits().end(), Clause->getInits().end() + VL.size(),
+            nullptr);
+  std::fill(Clause->getUpdates().end(), Clause->getUpdates().end() + VL.size(),
+            nullptr);
   Clause->setStep(Step);
+  Clause->setCalcStep(CalcStep);
   return Clause;
 }
 
 OMPLinearClause *OMPLinearClause::CreateEmpty(const ASTContext &C,
                                               unsigned NumVars) {
+  // Allocate space for 4 lists (Vars, Inits, Updates, Finals) and 2 expressions
+  // (Step and CalcStep).
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPLinearClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * (NumVars + 1));
+                         (4 * NumVars + 2) * sizeof(Expr *));
   return new (Mem) OMPLinearClause(NumVars);
 }
 
@@ -1331,17 +1395,41 @@ OMPAlignedClause *OMPAlignedClause::CreateEmpty(const ASTContext &C,
   return new (Mem) OMPAlignedClause(NumVars);
 }
 
-OMPCopyinClause *OMPCopyinClause::Create(const ASTContext &C,
-                                         SourceLocation StartLoc,
-                                         SourceLocation LParenLoc,
-                                         SourceLocation EndLoc,
-                                         ArrayRef<Expr *> VL) {
+void OMPCopyinClause::setSourceExprs(ArrayRef<Expr *> SrcExprs) {
+  assert(SrcExprs.size() == varlist_size() && "Number of source expressions is "
+                                              "not the same as the "
+                                              "preallocated buffer");
+  std::copy(SrcExprs.begin(), SrcExprs.end(), varlist_end());
+}
+
+void OMPCopyinClause::setDestinationExprs(ArrayRef<Expr *> DstExprs) {
+  assert(DstExprs.size() == varlist_size() && "Number of destination "
+                                              "expressions is not the same as "
+                                              "the preallocated buffer");
+  std::copy(DstExprs.begin(), DstExprs.end(), getSourceExprs().end());
+}
+
+void OMPCopyinClause::setAssignmentOps(ArrayRef<Expr *> AssignmentOps) {
+  assert(AssignmentOps.size() == varlist_size() &&
+         "Number of assignment expressions is not the same as the preallocated "
+         "buffer");
+  std::copy(AssignmentOps.begin(), AssignmentOps.end(),
+            getDestinationExprs().end());
+}
+
+OMPCopyinClause *OMPCopyinClause::Create(
+    const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
+    SourceLocation EndLoc, ArrayRef<Expr *> VL, ArrayRef<Expr *> SrcExprs,
+    ArrayRef<Expr *> DstExprs, ArrayRef<Expr *> AssignmentOps) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPCopyinClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * VL.size());
+                         4 * sizeof(Expr *) * VL.size());
   OMPCopyinClause *Clause = new (Mem) OMPCopyinClause(StartLoc, LParenLoc,
                                                       EndLoc, VL.size());
   Clause->setVarRefs(VL);
+  Clause->setSourceExprs(SrcExprs);
+  Clause->setDestinationExprs(DstExprs);
+  Clause->setAssignmentOps(AssignmentOps);
   return Clause;
 }
 
@@ -1349,21 +1437,45 @@ OMPCopyinClause *OMPCopyinClause::CreateEmpty(const ASTContext &C,
                                               unsigned N) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPCopyinClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * N);
+                         4 * sizeof(Expr *) * N);
   return new (Mem) OMPCopyinClause(N);
 }
 
-OMPCopyprivateClause *OMPCopyprivateClause::Create(const ASTContext &C,
-                                                   SourceLocation StartLoc,
-                                                   SourceLocation LParenLoc,
-                                                   SourceLocation EndLoc,
-                                                   ArrayRef<Expr *> VL) {
+void OMPCopyprivateClause::setSourceExprs(ArrayRef<Expr *> SrcExprs) {
+  assert(SrcExprs.size() == varlist_size() && "Number of source expressions is "
+                                              "not the same as the "
+                                              "preallocated buffer");
+  std::copy(SrcExprs.begin(), SrcExprs.end(), varlist_end());
+}
+
+void OMPCopyprivateClause::setDestinationExprs(ArrayRef<Expr *> DstExprs) {
+  assert(DstExprs.size() == varlist_size() && "Number of destination "
+                                              "expressions is not the same as "
+                                              "the preallocated buffer");
+  std::copy(DstExprs.begin(), DstExprs.end(), getSourceExprs().end());
+}
+
+void OMPCopyprivateClause::setAssignmentOps(ArrayRef<Expr *> AssignmentOps) {
+  assert(AssignmentOps.size() == varlist_size() &&
+         "Number of assignment expressions is not the same as the preallocated "
+         "buffer");
+  std::copy(AssignmentOps.begin(), AssignmentOps.end(),
+            getDestinationExprs().end());
+}
+
+OMPCopyprivateClause *OMPCopyprivateClause::Create(
+    const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
+    SourceLocation EndLoc, ArrayRef<Expr *> VL, ArrayRef<Expr *> SrcExprs,
+    ArrayRef<Expr *> DstExprs, ArrayRef<Expr *> AssignmentOps) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPCopyprivateClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * VL.size());
+                         4 * sizeof(Expr *) * VL.size());
   OMPCopyprivateClause *Clause =
       new (Mem) OMPCopyprivateClause(StartLoc, LParenLoc, EndLoc, VL.size());
   Clause->setVarRefs(VL);
+  Clause->setSourceExprs(SrcExprs);
+  Clause->setDestinationExprs(DstExprs);
+  Clause->setAssignmentOps(AssignmentOps);
   return Clause;
 }
 
@@ -1371,7 +1483,7 @@ OMPCopyprivateClause *OMPCopyprivateClause::CreateEmpty(const ASTContext &C,
                                                         unsigned N) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPCopyprivateClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * N);
+                         4 * sizeof(Expr *) * N);
   return new (Mem) OMPCopyprivateClause(N);
 }
 
@@ -1399,16 +1511,42 @@ void OMPLoopDirective::setFinals(ArrayRef<Expr *> A) {
   std::copy(A.begin(), A.end(), getFinals().begin());
 }
 
+void OMPReductionClause::setLHSExprs(ArrayRef<Expr *> LHSExprs) {
+  assert(
+      LHSExprs.size() == varlist_size() &&
+      "Number of LHS expressions is not the same as the preallocated buffer");
+  std::copy(LHSExprs.begin(), LHSExprs.end(), varlist_end());
+}
+
+void OMPReductionClause::setRHSExprs(ArrayRef<Expr *> RHSExprs) {
+  assert(
+      RHSExprs.size() == varlist_size() &&
+      "Number of RHS expressions is not the same as the preallocated buffer");
+  std::copy(RHSExprs.begin(), RHSExprs.end(), getLHSExprs().end());
+}
+
+void OMPReductionClause::setReductionOps(ArrayRef<Expr *> ReductionOps) {
+  assert(ReductionOps.size() == varlist_size() && "Number of reduction "
+                                                  "expressions is not the same "
+                                                  "as the preallocated buffer");
+  std::copy(ReductionOps.begin(), ReductionOps.end(), getRHSExprs().end());
+}
+
 OMPReductionClause *OMPReductionClause::Create(
     const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
     SourceLocation EndLoc, SourceLocation ColonLoc, ArrayRef<Expr *> VL,
-    NestedNameSpecifierLoc QualifierLoc, const DeclarationNameInfo &NameInfo) {
+    NestedNameSpecifierLoc QualifierLoc, const DeclarationNameInfo &NameInfo,
+    ArrayRef<Expr *> LHSExprs, ArrayRef<Expr *> RHSExprs,
+    ArrayRef<Expr *> ReductionOps) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPReductionClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * VL.size());
+                         4 * sizeof(Expr *) * VL.size());
   OMPReductionClause *Clause = new (Mem) OMPReductionClause(
       StartLoc, LParenLoc, EndLoc, ColonLoc, VL.size(), QualifierLoc, NameInfo);
   Clause->setVarRefs(VL);
+  Clause->setLHSExprs(LHSExprs);
+  Clause->setRHSExprs(RHSExprs);
+  Clause->setReductionOps(ReductionOps);
   return Clause;
 }
 
@@ -1416,7 +1554,7 @@ OMPReductionClause *OMPReductionClause::CreateEmpty(const ASTContext &C,
                                                     unsigned N) {
   void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPReductionClause),
                                                   llvm::alignOf<Expr *>()) +
-                         sizeof(Expr *) * N);
+                         4 * sizeof(Expr *) * N);
   return new (Mem) OMPReductionClause(N);
 }
 
@@ -1443,10 +1581,7 @@ OMPFlushClause *OMPFlushClause::CreateEmpty(const ASTContext &C, unsigned N) {
 
 const OMPClause *
 OMPExecutableDirective::getSingleClause(OpenMPClauseKind K) const {
-  auto ClauseFilter =
-      [=](const OMPClause *C) -> bool { return C->getClauseKind() == K; };
-  OMPExecutableDirective::filtered_clause_iterator<decltype(ClauseFilter)> I(
-      clauses(), ClauseFilter);
+  auto &&I = getClausesOfKind(K);
 
   if (I) {
     auto *Clause = *I;
@@ -1948,14 +2083,14 @@ OMPOrderedDirective *OMPOrderedDirective::CreateEmpty(const ASTContext &C,
   return new (Mem) OMPOrderedDirective();
 }
 
-OMPAtomicDirective *
-OMPAtomicDirective::Create(const ASTContext &C, SourceLocation StartLoc,
-                           SourceLocation EndLoc, ArrayRef<OMPClause *> Clauses,
-                           Stmt *AssociatedStmt, Expr *X, Expr *V, Expr *E) {
+OMPAtomicDirective *OMPAtomicDirective::Create(
+    const ASTContext &C, SourceLocation StartLoc, SourceLocation EndLoc,
+    ArrayRef<OMPClause *> Clauses, Stmt *AssociatedStmt, Expr *X, Expr *V,
+    Expr *E, Expr *UE, bool IsXLHSInRHSPart, bool IsPostfixUpdate) {
   unsigned Size = llvm::RoundUpToAlignment(sizeof(OMPAtomicDirective),
                                            llvm::alignOf<OMPClause *>());
   void *Mem = C.Allocate(Size + sizeof(OMPClause *) * Clauses.size() +
-                         4 * sizeof(Stmt *));
+                         5 * sizeof(Stmt *));
   OMPAtomicDirective *Dir =
       new (Mem) OMPAtomicDirective(StartLoc, EndLoc, Clauses.size());
   Dir->setClauses(Clauses);
@@ -1963,6 +2098,9 @@ OMPAtomicDirective::Create(const ASTContext &C, SourceLocation StartLoc,
   Dir->setX(X);
   Dir->setV(V);
   Dir->setExpr(E);
+  Dir->setUpdateExpr(UE);
+  Dir->IsXLHSInRHSPart = IsXLHSInRHSPart;
+  Dir->IsPostfixUpdate = IsPostfixUpdate;
   return Dir;
 }
 
@@ -1972,7 +2110,7 @@ OMPAtomicDirective *OMPAtomicDirective::CreateEmpty(const ASTContext &C,
   unsigned Size = llvm::RoundUpToAlignment(sizeof(OMPAtomicDirective),
                                            llvm::alignOf<OMPClause *>());
   void *Mem =
-      C.Allocate(Size + sizeof(OMPClause *) * NumClauses + 4 * sizeof(Stmt *));
+      C.Allocate(Size + sizeof(OMPClause *) * NumClauses + 5 * sizeof(Stmt *));
   return new (Mem) OMPAtomicDirective(NumClauses);
 }
 
diff --git a/lib/AST/StmtPrinter.cpp b/lib/AST/StmtPrinter.cpp
index 927a679244b5..dc4f9964c7a6 100644
--- a/lib/AST/StmtPrinter.cpp
+++ b/lib/AST/StmtPrinter.cpp
@@ -1069,7 +1069,8 @@ void StmtPrinter::VisitIntegerLiteral(IntegerLiteral *Node) {
   // Emit suffixes.  Integer literals are always a builtin integer type.
   switch (Node->getType()->getAs<BuiltinType>()->getKind()) {
   default: llvm_unreachable("Unexpected type for integer literal!");
-  case BuiltinType::SChar:     OS << "i8"; break;
+  case BuiltinType::Char_S:
+  case BuiltinType::Char_U:    OS << "i8"; break;
   case BuiltinType::UChar:     OS << "Ui8"; break;
   case BuiltinType::Short:     OS << "i16"; break;
   case BuiltinType::UShort:    OS << "Ui16"; break;
@@ -1373,24 +1374,24 @@ void StmtPrinter::VisitInitListExpr(InitListExpr* Node) {
     return;
   }
 
-  OS << "{ ";
+  OS << "{";
   for (unsigned i = 0, e = Node->getNumInits(); i != e; ++i) {
     if (i) OS << ", ";
     if (Node->getInit(i))
       PrintExpr(Node->getInit(i));
     else
-      OS << "0";
+      OS << "{}";
   }
-  OS << " }";
+  OS << "}";
 }
 
 void StmtPrinter::VisitParenListExpr(ParenListExpr* Node) {
-  OS << "( ";
+  OS << "(";
   for (unsigned i = 0, e = Node->getNumExprs(); i != e; ++i) {
     if (i) OS << ", ";
     PrintExpr(Node->getExpr(i));
   }
-  OS << " )";
+  OS << ")";
 }
 
 void StmtPrinter::VisitDesignatedInitExpr(DesignatedInitExpr *Node) {
@@ -1621,6 +1622,15 @@ void StmtPrinter::VisitUserDefinedLiteral(UserDefinedLiteral *Node) {
     const TemplateArgumentList *Args =
       cast<FunctionDecl>(DRE->getDecl())->getTemplateSpecializationArgs();
     assert(Args);
+
+    if (Args->size() != 1) {
+      OS << "operator \"\" " << Node->getUDSuffix()->getName();
+      TemplateSpecializationType::PrintTemplateArgumentList(
+          OS, Args->data(), Args->size(), Policy);
+      OS << "()";
+      return;
+    }
+
     const TemplateArgument &Pack = Args->get(0);
     for (const auto &P : Pack.pack_elements()) {
       char C = (char)P.getAsIntegral().getZExtValue();
@@ -1679,9 +1689,13 @@ void StmtPrinter::VisitCXXDefaultInitExpr(CXXDefaultInitExpr *Node) {
 
 void StmtPrinter::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *Node) {
   Node->getType().print(OS, Policy);
-  OS << "(";
+  // If there are no parens, this is list-initialization, and the braces are
+  // part of the syntax of the inner construct.
+  if (Node->getLParenLoc().isValid())
+    OS << "(";
   PrintExpr(Node->getSubExpr());
-  OS << ")";
+  if (Node->getLParenLoc().isValid())
+    OS << ")";
 }
 
 void StmtPrinter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *Node) {
@@ -1690,7 +1704,12 @@ void StmtPrinter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *Node) {
 
 void StmtPrinter::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *Node) {
   Node->getType().print(OS, Policy);
-  OS << "(";
+  if (Node->isStdInitListInitialization())
+    /* Nothing to do; braces are part of creating the std::initializer_list. */;
+  else if (Node->isListInitialization())
+    OS << "{";
+  else
+    OS << "(";
   for (CXXTemporaryObjectExpr::arg_iterator Arg = Node->arg_begin(),
                                          ArgEnd = Node->arg_end();
        Arg != ArgEnd; ++Arg) {
@@ -1700,7 +1719,12 @@ void StmtPrinter::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *Node) {
       OS << ", ";
     PrintExpr(*Arg);
   }
-  OS << ")";
+  if (Node->isStdInitListInitialization())
+    /* See above. */;
+  else if (Node->isListInitialization())
+    OS << "}";
+  else
+    OS << ")";
 }
 
 void StmtPrinter::VisitLambdaExpr(LambdaExpr *Node) {
@@ -1734,7 +1758,7 @@ void StmtPrinter::VisitLambdaExpr(LambdaExpr *Node) {
       break;
 
     case LCK_ByRef:
-      if (Node->getCaptureDefault() != LCD_ByRef || C->isInitCapture())
+      if (Node->getCaptureDefault() != LCD_ByRef || Node->isInitCapture(C))
         OS << '&';
       OS << C->getCapturedVar()->getName();
       break;
@@ -1746,7 +1770,7 @@ void StmtPrinter::VisitLambdaExpr(LambdaExpr *Node) {
       llvm_unreachable("VLA type in explicit captures.");
     }
 
-    if (C->isInitCapture())
+    if (Node->isInitCapture(C))
       PrintExpr(C->getCapturedVar()->getInit());
   }
   OS << ']';
@@ -1866,8 +1890,8 @@ void StmtPrinter::VisitCXXPseudoDestructorExpr(CXXPseudoDestructorExpr *E) {
 }
 
 void StmtPrinter::VisitCXXConstructExpr(CXXConstructExpr *E) {
-  if (E->isListInitialization())
-    OS << "{ ";
+  if (E->isListInitialization() && !E->isStdInitListInitialization())
+    OS << "{";
 
   for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
     if (isa<CXXDefaultArgExpr>(E->getArg(i))) {
@@ -1879,8 +1903,8 @@ void StmtPrinter::VisitCXXConstructExpr(CXXConstructExpr *E) {
     PrintExpr(E->getArg(i));
   }
 
-  if (E->isListInitialization())
-    OS << " }";
+  if (E->isListInitialization() && !E->isStdInitListInitialization())
+    OS << "}";
 }
 
 void StmtPrinter::VisitCXXStdInitializerListExpr(CXXStdInitializerListExpr *E) {
diff --git a/lib/AST/StmtProfile.cpp b/lib/AST/StmtProfile.cpp
index d1f25d63b3f9..c66b153eadbb 100644
--- a/lib/AST/StmtProfile.cpp
+++ b/lib/AST/StmtProfile.cpp
@@ -298,8 +298,12 @@ void OMPClauseProfiler::VisitOMPDefaultClause(const OMPDefaultClause *C) { }
 void OMPClauseProfiler::VisitOMPProcBindClause(const OMPProcBindClause *C) { }
 
 void OMPClauseProfiler::VisitOMPScheduleClause(const OMPScheduleClause *C) {
-  if (C->getChunkSize())
+  if (C->getChunkSize()) {
     Profiler->VisitStmt(C->getChunkSize());
+    if (C->getHelperChunkSize()) {
+      Profiler->VisitStmt(C->getChunkSize());
+    }
+  }
 }
 
 void OMPClauseProfiler::VisitOMPOrderedClause(const OMPOrderedClause *) {}
@@ -346,6 +350,15 @@ OMPClauseProfiler::VisitOMPFirstprivateClause(const OMPFirstprivateClause *C) {
 void
 OMPClauseProfiler::VisitOMPLastprivateClause(const OMPLastprivateClause *C) {
   VisitOMPClauseList(C);
+  for (auto *E : C->source_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->destination_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->assignment_ops()) {
+    Profiler->VisitStmt(E);
+  }
 }
 void OMPClauseProfiler::VisitOMPSharedClause(const OMPSharedClause *C) {
   VisitOMPClauseList(C);
@@ -356,10 +369,29 @@ void OMPClauseProfiler::VisitOMPReductionClause(
       C->getQualifierLoc().getNestedNameSpecifier());
   Profiler->VisitName(C->getNameInfo().getName());
   VisitOMPClauseList(C);
+  for (auto *E : C->lhs_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->rhs_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->reduction_ops()) {
+    Profiler->VisitStmt(E);
+  }
 }
 void OMPClauseProfiler::VisitOMPLinearClause(const OMPLinearClause *C) {
   VisitOMPClauseList(C);
+  for (auto *E : C->inits()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->updates()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->finals()) {
+    Profiler->VisitStmt(E);
+  }
   Profiler->VisitStmt(C->getStep());
+  Profiler->VisitStmt(C->getCalcStep());
 }
 void OMPClauseProfiler::VisitOMPAlignedClause(const OMPAlignedClause *C) {
   VisitOMPClauseList(C);
@@ -367,10 +399,28 @@ void OMPClauseProfiler::VisitOMPAlignedClause(const OMPAlignedClause *C) {
 }
 void OMPClauseProfiler::VisitOMPCopyinClause(const OMPCopyinClause *C) {
   VisitOMPClauseList(C);
+  for (auto *E : C->source_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->destination_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->assignment_ops()) {
+    Profiler->VisitStmt(E);
+  }
 }
 void
 OMPClauseProfiler::VisitOMPCopyprivateClause(const OMPCopyprivateClause *C) {
   VisitOMPClauseList(C);
+  for (auto *E : C->source_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->destination_exprs()) {
+    Profiler->VisitStmt(E);
+  }
+  for (auto *E : C->assignment_ops()) {
+    Profiler->VisitStmt(E);
+  }
 }
 void OMPClauseProfiler::VisitOMPFlushClause(const OMPFlushClause *C) {
   VisitOMPClauseList(C);
diff --git a/lib/AST/Type.cpp b/lib/AST/Type.cpp
index e4f364d04f86..09bb7692596c 100644
--- a/lib/AST/Type.cpp
+++ b/lib/AST/Type.cpp
@@ -170,15 +170,7 @@ DependentSizedExtVectorType::Profile(llvm::FoldingSetNodeID &ID,
 
 VectorType::VectorType(QualType vecType, unsigned nElements, QualType canonType,
                        VectorKind vecKind)
-  : Type(Vector, canonType, vecType->isDependentType(),
-         vecType->isInstantiationDependentType(),
-         vecType->isVariablyModifiedType(),
-         vecType->containsUnexpandedParameterPack()),
-    ElementType(vecType) 
-{
-  VectorTypeBits.VecKind = vecKind;
-  VectorTypeBits.NumElements = nElements;
-}
+    : VectorType(Vector, vecType, nElements, canonType, vecKind) {}
 
 VectorType::VectorType(TypeClass tc, QualType vecType, unsigned nElements,
                        QualType canonType, VectorKind vecKind)
@@ -640,12 +632,13 @@ bool Type::hasIntegerRepresentation() const {
 bool Type::isIntegralType(ASTContext &Ctx) const {
   if (const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType))
     return BT->getKind() >= BuiltinType::Bool &&
-    BT->getKind() <= BuiltinType::Int128;
-  
+           BT->getKind() <= BuiltinType::Int128;
+
+  // Complete enum types are integral in C.
   if (!Ctx.getLangOpts().CPlusPlus)
     if (const EnumType *ET = dyn_cast<EnumType>(CanonicalType))
-      return ET->getDecl()->isComplete(); // Complete enum types are integral in C.
-  
+      return ET->getDecl()->isComplete();
+
   return false;
 }
 
@@ -736,7 +729,7 @@ bool Type::isSignedIntegerType() const {
 bool Type::isSignedIntegerOrEnumerationType() const {
   if (const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType)) {
     return BT->getKind() >= BuiltinType::Char_S &&
-    BT->getKind() <= BuiltinType::Int128;
+           BT->getKind() <= BuiltinType::Int128;
   }
   
   if (const EnumType *ET = dyn_cast<EnumType>(CanonicalType)) {
@@ -1089,7 +1082,7 @@ bool QualType::isTrivialType(ASTContext &Context) const {
 
 bool QualType::isTriviallyCopyableType(ASTContext &Context) const {
   if ((*this)->isArrayType())
-    return Context.getBaseElementType(*this).isTrivialType(Context);
+    return Context.getBaseElementType(*this).isTriviallyCopyableType(Context);
 
   if (Context.getLangOpts().ObjCAutoRefCount) {
     switch (getObjCLifetime()) {
@@ -1586,8 +1579,9 @@ StringRef FunctionType::getNameForCallConv(CallingConv CC) {
   case CC_X86_64SysV: return "sysv_abi";
   case CC_AAPCS: return "aapcs";
   case CC_AAPCS_VFP: return "aapcs-vfp";
-  case CC_PnaclCall: return "pnaclcall";
   case CC_IntelOclBicc: return "intel_ocl_bicc";
+  case CC_SpirFunction: return "spir_function";
+  case CC_SpirKernel: return "spir_kernel";
   }
 
   llvm_unreachable("Invalid calling convention.");
@@ -1720,7 +1714,7 @@ bool FunctionProtoType::isNothrow(const ASTContext &Ctx,
   if (EST == EST_DynamicNone || EST == EST_BasicNoexcept)
     return true;
 
-  if (EST == EST_Dynamic && ResultIfDependent == true) {
+  if (EST == EST_Dynamic && ResultIfDependent) {
     // A dynamic exception specification is throwing unless every exception
     // type is an (unexpanded) pack expansion type.
     for (unsigned I = 0, N = NumExceptions; I != N; ++I)
@@ -1936,7 +1930,6 @@ bool AttributedType::isCallingConv() const {
   case attr_pascal:
   case attr_ms_abi:
   case attr_sysv_abi:
-  case attr_pnaclcall:
   case attr_inteloclbicc:
     return true;
   }
@@ -2378,6 +2371,11 @@ bool Type::isObjCNSObjectType() const {
     return typedefType->getDecl()->hasAttr<ObjCNSObjectAttr>();
   return false;
 }
+bool Type::isObjCIndependentClassType() const {
+  if (const TypedefType *typedefType = dyn_cast<TypedefType>(this))
+    return typedefType->getDecl()->hasAttr<ObjCIndependentClassAttr>();
+  return false;
+}
 bool Type::isObjCRetainableType() const {
   return isObjCObjectPointerType() ||
          isBlockPointerType() ||
diff --git a/lib/AST/TypePrinter.cpp b/lib/AST/TypePrinter.cpp
index e36fc175c449..3928fe8f8942 100644
--- a/lib/AST/TypePrinter.cpp
+++ b/lib/AST/TypePrinter.cpp
@@ -110,7 +110,7 @@ namespace {
   };
 }
 
-static void AppendTypeQualList(raw_ostream &OS, unsigned TypeQuals) {
+static void AppendTypeQualList(raw_ostream &OS, unsigned TypeQuals, bool C99) {
   bool appendSpace = false;
   if (TypeQuals & Qualifiers::Const) {
     OS << "const";
@@ -123,7 +123,11 @@ static void AppendTypeQualList(raw_ostream &OS, unsigned TypeQuals) {
   }
   if (TypeQuals & Qualifiers::Restrict) {
     if (appendSpace) OS << ' ';
-    OS << "restrict";
+    if (C99) {
+      OS << "restrict";
+    } else {
+      OS << "__restrict";
+    }
   }
 }
 
@@ -432,7 +436,7 @@ void TypePrinter::printConstantArrayAfter(const ConstantArrayType *T,
                                           raw_ostream &OS) {
   OS << '[';
   if (T->getIndexTypeQualifiers().hasQualifiers()) {
-    AppendTypeQualList(OS, T->getIndexTypeCVRQualifiers());
+    AppendTypeQualList(OS, T->getIndexTypeCVRQualifiers(), Policy.LangOpts.C99);
     OS << ' ';
   }
 
@@ -465,7 +469,7 @@ void TypePrinter::printVariableArrayAfter(const VariableArrayType *T,
                                           raw_ostream &OS) {
   OS << '[';
   if (T->getIndexTypeQualifiers().hasQualifiers()) {
-    AppendTypeQualList(OS, T->getIndexTypeCVRQualifiers());
+    AppendTypeQualList(OS, T->getIndexTypeCVRQualifiers(), Policy.LangOpts.C99);
     OS << ' ';
   }
 
@@ -685,9 +689,6 @@ void TypePrinter::printFunctionProtoAfter(const FunctionProtoType *T,
     case CC_AAPCS_VFP:
       OS << " __attribute__((pcs(\"aapcs-vfp\")))";
       break;
-    case CC_PnaclCall:
-      OS << " __attribute__((pnaclcall))";
-      break;
     case CC_IntelOclBicc:
       OS << " __attribute__((intel_ocl_bicc))";
       break;
@@ -697,6 +698,10 @@ void TypePrinter::printFunctionProtoAfter(const FunctionProtoType *T,
     case CC_X86_64SysV:
       OS << " __attribute__((sysv_abi))";
       break;
+    case CC_SpirFunction:
+    case CC_SpirKernel:
+      // Do nothing. These CCs are not available as attributes.
+      break;
     }
   }
 
@@ -708,7 +713,7 @@ void TypePrinter::printFunctionProtoAfter(const FunctionProtoType *T,
 
   if (unsigned quals = T->getTypeQuals()) {
     OS << ' ';
-    AppendTypeQualList(OS, quals);
+    AppendTypeQualList(OS, quals, Policy.LangOpts.C99);
   }
 
   switch (T->getRefQualifier()) {
@@ -1253,7 +1258,6 @@ void TypePrinter::printAttributedAfter(const AttributedType *T,
    OS << ')';
    break;
   }
-  case AttributedType::attr_pnaclcall: OS << "pnaclcall"; break;
   case AttributedType::attr_inteloclbicc: OS << "inteloclbicc"; break;
   }
   OS << "))";
@@ -1473,7 +1477,7 @@ void Qualifiers::print(raw_ostream &OS, const PrintingPolicy& Policy,
 
   unsigned quals = getCVRQualifiers();
   if (quals) {
-    AppendTypeQualList(OS, quals);
+    AppendTypeQualList(OS, quals, Policy.LangOpts.C99);
     addSpace = true;
   }
   if (unsigned addrspace = getAddressSpace()) {
diff --git a/lib/AST/VTableBuilder.cpp b/lib/AST/VTableBuilder.cpp
index ddb1f057ac8e..ca5f0aad0013 100644
--- a/lib/AST/VTableBuilder.cpp
+++ b/lib/AST/VTableBuilder.cpp
@@ -13,9 +13,11 @@
 
 #include "clang/AST/VTableBuilder.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/AST/ASTDiagnostic.h"
 #include "clang/AST/CXXInheritance.h"
 #include "clang/AST/RecordLayout.h"
 #include "clang/Basic/TargetInfo.h"
+#include "llvm/ADT/SetOperations.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/raw_ostream.h"
@@ -216,7 +218,7 @@ FinalOverriders::FinalOverriders(const CXXRecordDecl *MostDerivedClass,
 #endif
 }
 
-static BaseOffset ComputeBaseOffset(ASTContext &Context, 
+static BaseOffset ComputeBaseOffset(const ASTContext &Context,
                                     const CXXRecordDecl *DerivedRD,
                                     const CXXBasePath &Path) {
   CharUnits NonVirtualOffset = CharUnits::Zero();
@@ -255,7 +257,7 @@ static BaseOffset ComputeBaseOffset(ASTContext &Context,
   
 }
 
-static BaseOffset ComputeBaseOffset(ASTContext &Context, 
+static BaseOffset ComputeBaseOffset(const ASTContext &Context,
                                     const CXXRecordDecl *BaseRD,
                                     const CXXRecordDecl *DerivedRD) {
   CXXBasePaths Paths(/*FindAmbiguities=*/false,
@@ -411,7 +413,8 @@ void FinalOverriders::dump(raw_ostream &Out, BaseSubobject Base,
   for (const auto *MD : RD->methods()) {
     if (!MD->isVirtual())
       continue;
-  
+    MD = MD->getCanonicalDecl();
+
     OverriderInfo Overrider = getOverrider(MD, Base.getBaseOffset());
 
     Out << "  ";
@@ -695,6 +698,7 @@ void VCallAndVBaseOffsetBuilder::AddVCallOffsets(BaseSubobject Base,
   for (const auto *MD : RD->methods()) {
     if (!MD->isVirtual())
       continue;
+    MD = MD->getCanonicalDecl();
 
     CharUnits OffsetOffset = getCurrentOffsetOffset();
     
@@ -1514,6 +1518,7 @@ void ItaniumVTableBuilder::AddMethods(
   for (const auto *MD : RD->methods()) {
     if (!MD->isVirtual())
       continue;
+    MD = MD->getCanonicalDecl();
 
     // Get the final overrider.
     FinalOverriders::OverriderInfo Overrider = 
@@ -2196,6 +2201,7 @@ void ItaniumVTableBuilder::dumpLayout(raw_ostream &Out) {
     // We only want virtual member functions.
     if (!MD->isVirtual())
       continue;
+    MD = MD->getCanonicalDecl();
 
     std::string MethodName =
       PredefinedExpr::ComputeName(PredefinedExpr::PrettyFunctionNoVirtual,
@@ -2585,7 +2591,9 @@ public:
     // Only include the RTTI component if we know that we will provide a
     // definition of the vftable.
     HasRTTIComponent = Context.getLangOpts().RTTIData &&
-                       !MostDerivedClass->hasAttr<DLLImportAttr>();
+                       !MostDerivedClass->hasAttr<DLLImportAttr>() &&
+                       MostDerivedClass->getTemplateSpecializationKind() !=
+                           TSK_ExplicitInstantiationDeclaration;
 
     LayoutVFTable();
 
@@ -2625,8 +2633,6 @@ public:
   void dumpLayout(raw_ostream &);
 };
 
-} // end namespace
-
 /// InitialOverriddenDefinitionCollector - Finds the set of least derived bases
 /// that define the given method.
 struct InitialOverriddenDefinitionCollector {
@@ -2641,6 +2647,8 @@ struct InitialOverriddenDefinitionCollector {
   }
 };
 
+} // end namespace
+
 static bool BaseInSet(const CXXBaseSpecifier *Specifier,
                       CXXBasePath &Path, void *BasesSet) {
   BasesSetVectorTy *Bases = (BasesSetVectorTy *)BasesSet;
@@ -2730,8 +2738,9 @@ VFTableBuilder::ComputeThisOffset(FinalOverriders::OverriderInfo Overrider) {
     CharUnits ThisOffset = Overrider.Offset;
     CharUnits LastVBaseOffset;
 
-    // For each path from the overrider to the parents of the overridden methods,
-    // traverse the path, calculating the this offset in the most derived class.
+    // For each path from the overrider to the parents of the overridden
+    // methods, traverse the path, calculating the this offset in the most
+    // derived class.
     for (int J = 0, F = Path.size(); J != F; ++J) {
       const CXXBasePathElement &Element = Path[J];
       QualType CurTy = Element.Base->getType();
@@ -2930,6 +2939,7 @@ static void GroupNewVirtualOverloads(
   typedef llvm::DenseMap<DeclarationName, unsigned> VisitedGroupIndicesTy;
   VisitedGroupIndicesTy VisitedGroupIndices;
   for (const auto *MD : RD->methods()) {
+    MD = MD->getCanonicalDecl();
     VisitedGroupIndicesTy::iterator J;
     bool Inserted;
     std::tie(J, Inserted) = VisitedGroupIndices.insert(
@@ -2962,7 +2972,8 @@ void VFTableBuilder::AddMethods(BaseSubobject Base, unsigned BaseDepth,
   const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
 
   // See if this class expands a vftable of the base we look at, which is either
-  // the one defined by the vfptr base path or the primary base of the current class.
+  // the one defined by the vfptr base path or the primary base of the current
+  // class.
   const CXXRecordDecl *NextBase = nullptr, *NextLastVBase = LastVBase;
   CharUnits NextBaseOffset;
   if (BaseDepth < WhichVFPtr.PathToBaseWithVPtr.size()) {
@@ -3020,7 +3031,8 @@ void VFTableBuilder::AddMethods(BaseSubobject Base, unsigned BaseDepth,
                                   ThisAdjustmentOffset);
 
     if (OverriddenMD) {
-      // If MD overrides anything in this vftable, we need to update the entries.
+      // If MD overrides anything in this vftable, we need to update the
+      // entries.
       MethodInfoMapTy::iterator OverriddenMDIterator =
           MethodInfoMap.find(OverriddenMD);
 
@@ -3435,55 +3447,176 @@ MicrosoftVTableContext::~MicrosoftVTableContext() {
   llvm::DeleteContainerSeconds(VBaseInfo);
 }
 
-static bool
-findPathForVPtr(ASTContext &Context, const ASTRecordLayout &MostDerivedLayout,
-                const CXXRecordDecl *RD, CharUnits Offset,
-                llvm::SmallPtrSetImpl<const CXXRecordDecl *> &VBasesSeen,
-                VPtrInfo::BasePath &FullPath, VPtrInfo *Info) {
-  if (RD == Info->BaseWithVPtr && Offset == Info->FullOffsetInMDC) {
-    Info->PathToBaseWithVPtr = FullPath;
-    return true;
+namespace {
+typedef llvm::SetVector<BaseSubobject, std::vector<BaseSubobject>,
+                        llvm::DenseSet<BaseSubobject>> FullPathTy;
+}
+
+// This recursive function finds all paths from a subobject centered at
+// (RD, Offset) to the subobject located at BaseWithVPtr.
+static void findPathsToSubobject(ASTContext &Context,
+                                 const ASTRecordLayout &MostDerivedLayout,
+                                 const CXXRecordDecl *RD, CharUnits Offset,
+                                 BaseSubobject BaseWithVPtr,
+                                 FullPathTy &FullPath,
+                                 std::list<FullPathTy> &Paths) {
+  if (BaseSubobject(RD, Offset) == BaseWithVPtr) {
+    Paths.push_back(FullPath);
+    return;
   }
 
   const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
 
-  // Recurse with non-virtual bases first.
-  // FIXME: Does this need to be in layout order? Virtual bases will be in base
-  // specifier order, which isn't necessarily layout order.
-  SmallVector<CXXBaseSpecifier, 4> Bases(RD->bases_begin(), RD->bases_end());
-  std::stable_partition(Bases.begin(), Bases.end(),
-                        [](CXXBaseSpecifier bs) { return !bs.isVirtual(); });
-
-  for (const auto &B : Bases) {
-    const CXXRecordDecl *Base = B.getType()->getAsCXXRecordDecl();
-    CharUnits NewOffset;
-    if (!B.isVirtual())
-      NewOffset = Offset + Layout.getBaseClassOffset(Base);
-    else {
-      if (!VBasesSeen.insert(Base).second)
-        return false;
-      NewOffset = MostDerivedLayout.getVBaseClassOffset(Base);
-    }
-    FullPath.push_back(Base);
-    if (findPathForVPtr(Context, MostDerivedLayout, Base, NewOffset, VBasesSeen,
-                        FullPath, Info))
-      return true;
+  for (const CXXBaseSpecifier &BS : RD->bases()) {
+    const CXXRecordDecl *Base = BS.getType()->getAsCXXRecordDecl();
+    CharUnits NewOffset = BS.isVirtual()
+                              ? MostDerivedLayout.getVBaseClassOffset(Base)
+                              : Offset + Layout.getBaseClassOffset(Base);
+    FullPath.insert(BaseSubobject(Base, NewOffset));
+    findPathsToSubobject(Context, MostDerivedLayout, Base, NewOffset,
+                         BaseWithVPtr, FullPath, Paths);
     FullPath.pop_back();
   }
-  return false;
+}
+
+// Return the paths which are not subsets of other paths.
+static void removeRedundantPaths(std::list<FullPathTy> &FullPaths) {
+  FullPaths.remove_if([&](const FullPathTy &SpecificPath) {
+    for (const FullPathTy &OtherPath : FullPaths) {
+      if (&SpecificPath == &OtherPath)
+        continue;
+      if (std::all_of(SpecificPath.begin(), SpecificPath.end(),
+                      [&](const BaseSubobject &BSO) {
+                        return OtherPath.count(BSO) != 0;
+                      })) {
+        return true;
+      }
+    }
+    return false;
+  });
+}
+
+static CharUnits getOffsetOfFullPath(ASTContext &Context,
+                                     const CXXRecordDecl *RD,
+                                     const FullPathTy &FullPath) {
+  const ASTRecordLayout &MostDerivedLayout =
+      Context.getASTRecordLayout(RD);
+  CharUnits Offset = CharUnits::fromQuantity(-1);
+  for (const BaseSubobject &BSO : FullPath) {
+    const CXXRecordDecl *Base = BSO.getBase();
+    // The first entry in the path is always the most derived record, skip it.
+    if (Base == RD) {
+      assert(Offset.getQuantity() == -1);
+      Offset = CharUnits::Zero();
+      continue;
+    }
+    assert(Offset.getQuantity() != -1);
+    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
+    // While we know which base has to be traversed, we don't know if that base
+    // was a virtual base.
+    const CXXBaseSpecifier *BaseBS = std::find_if(
+        RD->bases_begin(), RD->bases_end(), [&](const CXXBaseSpecifier &BS) {
+          return BS.getType()->getAsCXXRecordDecl() == Base;
+        });
+    Offset = BaseBS->isVirtual() ? MostDerivedLayout.getVBaseClassOffset(Base)
+                                 : Offset + Layout.getBaseClassOffset(Base);
+    RD = Base;
+  }
+  return Offset;
+}
+
+// We want to select the path which introduces the most covariant overrides.  If
+// two paths introduce overrides which the other path doesn't contain, issue a
+// diagnostic.
+static const FullPathTy *selectBestPath(ASTContext &Context,
+                                        const CXXRecordDecl *RD, VPtrInfo *Info,
+                                        std::list<FullPathTy> &FullPaths) {
+  // Handle some easy cases first.
+  if (FullPaths.empty())
+    return nullptr;
+  if (FullPaths.size() == 1)
+    return &FullPaths.front();
+
+  const FullPathTy *BestPath = nullptr;
+  typedef std::set<const CXXMethodDecl *> OverriderSetTy;
+  OverriderSetTy LastOverrides;
+  for (const FullPathTy &SpecificPath : FullPaths) {
+    assert(!SpecificPath.empty());
+    OverriderSetTy CurrentOverrides;
+    const CXXRecordDecl *TopLevelRD = SpecificPath.begin()->getBase();
+    // Find the distance from the start of the path to the subobject with the
+    // VPtr.
+    CharUnits BaseOffset =
+        getOffsetOfFullPath(Context, TopLevelRD, SpecificPath);
+    FinalOverriders Overriders(TopLevelRD, CharUnits::Zero(), TopLevelRD);
+    for (const CXXMethodDecl *MD : Info->BaseWithVPtr->methods()) {
+      if (!MD->isVirtual())
+        continue;
+      FinalOverriders::OverriderInfo OI =
+          Overriders.getOverrider(MD->getCanonicalDecl(), BaseOffset);
+      const CXXMethodDecl *OverridingMethod = OI.Method;
+      // Only overriders which have a return adjustment introduce problematic
+      // thunks.
+      if (ComputeReturnAdjustmentBaseOffset(Context, OverridingMethod, MD)
+              .isEmpty())
+        continue;
+      // It's possible that the overrider isn't in this path.  If so, skip it
+      // because this path didn't introduce it.
+      const CXXRecordDecl *OverridingParent = OverridingMethod->getParent();
+      if (std::none_of(SpecificPath.begin(), SpecificPath.end(),
+                       [&](const BaseSubobject &BSO) {
+                         return BSO.getBase() == OverridingParent;
+                       }))
+        continue;
+      CurrentOverrides.insert(OverridingMethod);
+    }
+    OverriderSetTy NewOverrides =
+        llvm::set_difference(CurrentOverrides, LastOverrides);
+    if (NewOverrides.empty())
+      continue;
+    OverriderSetTy MissingOverrides =
+        llvm::set_difference(LastOverrides, CurrentOverrides);
+    if (MissingOverrides.empty()) {
+      // This path is a strict improvement over the last path, let's use it.
+      BestPath = &SpecificPath;
+      std::swap(CurrentOverrides, LastOverrides);
+    } else {
+      // This path introduces an overrider with a conflicting covariant thunk.
+      DiagnosticsEngine &Diags = Context.getDiagnostics();
+      const CXXMethodDecl *CovariantMD = *NewOverrides.begin();
+      const CXXMethodDecl *ConflictMD = *MissingOverrides.begin();
+      Diags.Report(RD->getLocation(), diag::err_vftable_ambiguous_component)
+          << RD;
+      Diags.Report(CovariantMD->getLocation(), diag::note_covariant_thunk)
+          << CovariantMD;
+      Diags.Report(ConflictMD->getLocation(), diag::note_covariant_thunk)
+          << ConflictMD;
+    }
+  }
+  // Go with the path that introduced the most covariant overrides.  If there is
+  // no such path, pick the first path.
+  return BestPath ? BestPath : &FullPaths.front();
 }
 
 static void computeFullPathsForVFTables(ASTContext &Context,
                                         const CXXRecordDecl *RD,
                                         VPtrInfoVector &Paths) {
-  llvm::SmallPtrSet<const CXXRecordDecl*, 4> VBasesSeen;
   const ASTRecordLayout &MostDerivedLayout = Context.getASTRecordLayout(RD);
-  VPtrInfo::BasePath FullPath;
+  FullPathTy FullPath;
+  std::list<FullPathTy> FullPaths;
   for (VPtrInfo *Info : Paths) {
-    findPathForVPtr(Context, MostDerivedLayout, RD, CharUnits::Zero(),
-                    VBasesSeen, FullPath, Info);
-    VBasesSeen.clear();
+    findPathsToSubobject(
+        Context, MostDerivedLayout, RD, CharUnits::Zero(),
+        BaseSubobject(Info->BaseWithVPtr, Info->FullOffsetInMDC), FullPath,
+        FullPaths);
     FullPath.clear();
+    removeRedundantPaths(FullPaths);
+    Info->PathToBaseWithVPtr.clear();
+    if (const FullPathTy *BestPath =
+            selectBestPath(Context, RD, Info, FullPaths))
+      for (const BaseSubobject &BSO : *BestPath)
+        Info->PathToBaseWithVPtr.push_back(BSO.getBase());
+    FullPaths.clear();
   }
 }