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diff --git a/contrib/llvm-project/clang/lib/Sema/SemaInit.cpp b/contrib/llvm-project/clang/lib/Sema/SemaInit.cpp
new file mode 100644
index 000000000000..60f34775c6b2
--- /dev/null
+++ b/contrib/llvm-project/clang/lib/Sema/SemaInit.cpp
@@ -0,0 +1,9566 @@
+//===--- SemaInit.cpp - Semantic Analysis for Initializers ----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements semantic analysis for initializers.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/ExprObjC.h"
+#include "clang/AST/ExprOpenMP.h"
+#include "clang/AST/TypeLoc.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/Sema/Designator.h"
+#include "clang/Sema/Initialization.h"
+#include "clang/Sema/Lookup.h"
+#include "clang/Sema/SemaInternal.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// Sema Initialization Checking
+//===----------------------------------------------------------------------===//
+
+/// Check whether T is compatible with a wide character type (wchar_t,
+/// char16_t or char32_t).
+static bool IsWideCharCompatible(QualType T, ASTContext &Context) {
+  if (Context.typesAreCompatible(Context.getWideCharType(), T))
+    return true;
+  if (Context.getLangOpts().CPlusPlus || Context.getLangOpts().C11) {
+    return Context.typesAreCompatible(Context.Char16Ty, T) ||
+           Context.typesAreCompatible(Context.Char32Ty, T);
+  }
+  return false;
+}
+
+enum StringInitFailureKind {
+  SIF_None,
+  SIF_NarrowStringIntoWideChar,
+  SIF_WideStringIntoChar,
+  SIF_IncompatWideStringIntoWideChar,
+  SIF_UTF8StringIntoPlainChar,
+  SIF_PlainStringIntoUTF8Char,
+  SIF_Other
+};
+
+/// Check whether the array of type AT can be initialized by the Init
+/// expression by means of string initialization. Returns SIF_None if so,
+/// otherwise returns a StringInitFailureKind that describes why the
+/// initialization would not work.
+static StringInitFailureKind IsStringInit(Expr *Init, const ArrayType *AT,
+                                          ASTContext &Context) {
+  if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT))
+    return SIF_Other;
+
+  // See if this is a string literal or @encode.
+  Init = Init->IgnoreParens();
+
+  // Handle @encode, which is a narrow string.
+  if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType())
+    return SIF_None;
+
+  // Otherwise we can only handle string literals.
+  StringLiteral *SL = dyn_cast<StringLiteral>(Init);
+  if (!SL)
+    return SIF_Other;
+
+  const QualType ElemTy =
+      Context.getCanonicalType(AT->getElementType()).getUnqualifiedType();
+
+  switch (SL->getKind()) {
+  case StringLiteral::UTF8:
+    // char8_t array can be initialized with a UTF-8 string.
+    if (ElemTy->isChar8Type())
+      return SIF_None;
+    LLVM_FALLTHROUGH;
+  case StringLiteral::Ascii:
+    // char array can be initialized with a narrow string.
+    // Only allow char x[] = "foo";  not char x[] = L"foo";
+    if (ElemTy->isCharType())
+      return (SL->getKind() == StringLiteral::UTF8 &&
+              Context.getLangOpts().Char8)
+                 ? SIF_UTF8StringIntoPlainChar
+                 : SIF_None;
+    if (ElemTy->isChar8Type())
+      return SIF_PlainStringIntoUTF8Char;
+    if (IsWideCharCompatible(ElemTy, Context))
+      return SIF_NarrowStringIntoWideChar;
+    return SIF_Other;
+  // C99 6.7.8p15 (with correction from DR343), or C11 6.7.9p15:
+  // "An array with element type compatible with a qualified or unqualified
+  // version of wchar_t, char16_t, or char32_t may be initialized by a wide
+  // string literal with the corresponding encoding prefix (L, u, or U,
+  // respectively), optionally enclosed in braces.
+  case StringLiteral::UTF16:
+    if (Context.typesAreCompatible(Context.Char16Ty, ElemTy))
+      return SIF_None;
+    if (ElemTy->isCharType() || ElemTy->isChar8Type())
+      return SIF_WideStringIntoChar;
+    if (IsWideCharCompatible(ElemTy, Context))
+      return SIF_IncompatWideStringIntoWideChar;
+    return SIF_Other;
+  case StringLiteral::UTF32:
+    if (Context.typesAreCompatible(Context.Char32Ty, ElemTy))
+      return SIF_None;
+    if (ElemTy->isCharType() || ElemTy->isChar8Type())
+      return SIF_WideStringIntoChar;
+    if (IsWideCharCompatible(ElemTy, Context))
+      return SIF_IncompatWideStringIntoWideChar;
+    return SIF_Other;
+  case StringLiteral::Wide:
+    if (Context.typesAreCompatible(Context.getWideCharType(), ElemTy))
+      return SIF_None;
+    if (ElemTy->isCharType() || ElemTy->isChar8Type())
+      return SIF_WideStringIntoChar;
+    if (IsWideCharCompatible(ElemTy, Context))
+      return SIF_IncompatWideStringIntoWideChar;
+    return SIF_Other;
+  }
+
+  llvm_unreachable("missed a StringLiteral kind?");
+}
+
+static StringInitFailureKind IsStringInit(Expr *init, QualType declType,
+                                          ASTContext &Context) {
+  const ArrayType *arrayType = Context.getAsArrayType(declType);
+  if (!arrayType)
+    return SIF_Other;
+  return IsStringInit(init, arrayType, Context);
+}
+
+/// Update the type of a string literal, including any surrounding parentheses,
+/// to match the type of the object which it is initializing.
+static void updateStringLiteralType(Expr *E, QualType Ty) {
+  while (true) {
+    E->setType(Ty);
+    E->setValueKind(VK_RValue);
+    if (isa<StringLiteral>(E) || isa<ObjCEncodeExpr>(E)) {
+      break;
+    } else if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
+      E = PE->getSubExpr();
+    } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
+      assert(UO->getOpcode() == UO_Extension);
+      E = UO->getSubExpr();
+    } else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E)) {
+      E = GSE->getResultExpr();
+    } else if (ChooseExpr *CE = dyn_cast<ChooseExpr>(E)) {
+      E = CE->getChosenSubExpr();
+    } else {
+      llvm_unreachable("unexpected expr in string literal init");
+    }
+  }
+}
+
+/// Fix a compound literal initializing an array so it's correctly marked
+/// as an rvalue.
+static void updateGNUCompoundLiteralRValue(Expr *E) {
+  while (true) {
+    E->setValueKind(VK_RValue);
+    if (isa<CompoundLiteralExpr>(E)) {
+      break;
+    } else if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
+      E = PE->getSubExpr();
+    } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
+      assert(UO->getOpcode() == UO_Extension);
+      E = UO->getSubExpr();
+    } else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E)) {
+      E = GSE->getResultExpr();
+    } else if (ChooseExpr *CE = dyn_cast<ChooseExpr>(E)) {
+      E = CE->getChosenSubExpr();
+    } else {
+      llvm_unreachable("unexpected expr in array compound literal init");
+    }
+  }
+}
+
+static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT,
+                            Sema &S) {
+  // Get the length of the string as parsed.
+  auto *ConstantArrayTy =
+      cast<ConstantArrayType>(Str->getType()->getAsArrayTypeUnsafe());
+  uint64_t StrLength = ConstantArrayTy->getSize().getZExtValue();
+
+  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
+    // C99 6.7.8p14. We have an array of character type with unknown size
+    // being initialized to a string literal.
+    llvm::APInt ConstVal(32, StrLength);
+    // Return a new array type (C99 6.7.8p22).
+    DeclT = S.Context.getConstantArrayType(IAT->getElementType(),
+                                           ConstVal,
+                                           ArrayType::Normal, 0);
+    updateStringLiteralType(Str, DeclT);
+    return;
+  }
+
+  const ConstantArrayType *CAT = cast<ConstantArrayType>(AT);
+
+  // We have an array of character type with known size.  However,
+  // the size may be smaller or larger than the string we are initializing.
+  // FIXME: Avoid truncation for 64-bit length strings.
+  if (S.getLangOpts().CPlusPlus) {
+    if (StringLiteral *SL = dyn_cast<StringLiteral>(Str->IgnoreParens())) {
+      // For Pascal strings it's OK to strip off the terminating null character,
+      // so the example below is valid:
+      //
+      // unsigned char a[2] = "\pa";
+      if (SL->isPascal())
+        StrLength--;
+    }
+
+    // [dcl.init.string]p2
+    if (StrLength > CAT->getSize().getZExtValue())
+      S.Diag(Str->getBeginLoc(),
+             diag::err_initializer_string_for_char_array_too_long)
+          << Str->getSourceRange();
+  } else {
+    // C99 6.7.8p14.
+    if (StrLength-1 > CAT->getSize().getZExtValue())
+      S.Diag(Str->getBeginLoc(),
+             diag::ext_initializer_string_for_char_array_too_long)
+          << Str->getSourceRange();
+  }
+
+  // Set the type to the actual size that we are initializing.  If we have
+  // something like:
+  //   char x[1] = "foo";
+  // then this will set the string literal's type to char[1].
+  updateStringLiteralType(Str, DeclT);
+}
+
+//===----------------------------------------------------------------------===//
+// Semantic checking for initializer lists.
+//===----------------------------------------------------------------------===//
+
+namespace {
+
+/// Semantic checking for initializer lists.
+///
+/// The InitListChecker class contains a set of routines that each
+/// handle the initialization of a certain kind of entity, e.g.,
+/// arrays, vectors, struct/union types, scalars, etc. The
+/// InitListChecker itself performs a recursive walk of the subobject
+/// structure of the type to be initialized, while stepping through
+/// the initializer list one element at a time. The IList and Index
+/// parameters to each of the Check* routines contain the active
+/// (syntactic) initializer list and the index into that initializer
+/// list that represents the current initializer. Each routine is
+/// responsible for moving that Index forward as it consumes elements.
+///
+/// Each Check* routine also has a StructuredList/StructuredIndex
+/// arguments, which contains the current "structured" (semantic)
+/// initializer list and the index into that initializer list where we
+/// are copying initializers as we map them over to the semantic
+/// list. Once we have completed our recursive walk of the subobject
+/// structure, we will have constructed a full semantic initializer
+/// list.
+///
+/// C99 designators cause changes in the initializer list traversal,
+/// because they make the initialization "jump" into a specific
+/// subobject and then continue the initialization from that
+/// point. CheckDesignatedInitializer() recursively steps into the
+/// designated subobject and manages backing out the recursion to
+/// initialize the subobjects after the one designated.
+class InitListChecker {
+  Sema &SemaRef;
+  bool hadError;
+  bool VerifyOnly; // no diagnostics, no structure building
+  bool TreatUnavailableAsInvalid; // Used only in VerifyOnly mode.
+  llvm::DenseMap<InitListExpr *, InitListExpr *> SyntacticToSemantic;
+  InitListExpr *FullyStructuredList;
+
+  void CheckImplicitInitList(const InitializedEntity &Entity,
+                             InitListExpr *ParentIList, QualType T,
+                             unsigned &Index, InitListExpr *StructuredList,
+                             unsigned &StructuredIndex);
+  void CheckExplicitInitList(const InitializedEntity &Entity,
+                             InitListExpr *IList, QualType &T,
+                             InitListExpr *StructuredList,
+                             bool TopLevelObject = false);
+  void CheckListElementTypes(const InitializedEntity &Entity,
+                             InitListExpr *IList, QualType &DeclType,
+                             bool SubobjectIsDesignatorContext,
+                             unsigned &Index,
+                             InitListExpr *StructuredList,
+                             unsigned &StructuredIndex,
+                             bool TopLevelObject = false);
+  void CheckSubElementType(const InitializedEntity &Entity,
+                           InitListExpr *IList, QualType ElemType,
+                           unsigned &Index,
+                           InitListExpr *StructuredList,
+                           unsigned &StructuredIndex);
+  void CheckComplexType(const InitializedEntity &Entity,
+                        InitListExpr *IList, QualType DeclType,
+                        unsigned &Index,
+                        InitListExpr *StructuredList,
+                        unsigned &StructuredIndex);
+  void CheckScalarType(const InitializedEntity &Entity,
+                       InitListExpr *IList, QualType DeclType,
+                       unsigned &Index,
+                       InitListExpr *StructuredList,
+                       unsigned &StructuredIndex);
+  void CheckReferenceType(const InitializedEntity &Entity,
+                          InitListExpr *IList, QualType DeclType,
+                          unsigned &Index,
+                          InitListExpr *StructuredList,
+                          unsigned &StructuredIndex);
+  void CheckVectorType(const InitializedEntity &Entity,
+                       InitListExpr *IList, QualType DeclType, unsigned &Index,
+                       InitListExpr *StructuredList,
+                       unsigned &StructuredIndex);
+  void CheckStructUnionTypes(const InitializedEntity &Entity,
+                             InitListExpr *IList, QualType DeclType,
+                             CXXRecordDecl::base_class_range Bases,
+                             RecordDecl::field_iterator Field,
+                             bool SubobjectIsDesignatorContext, unsigned &Index,
+                             InitListExpr *StructuredList,
+                             unsigned &StructuredIndex,
+                             bool TopLevelObject = false);
+  void CheckArrayType(const InitializedEntity &Entity,
+                      InitListExpr *IList, QualType &DeclType,
+                      llvm::APSInt elementIndex,
+                      bool SubobjectIsDesignatorContext, unsigned &Index,
+                      InitListExpr *StructuredList,
+                      unsigned &StructuredIndex);
+  bool CheckDesignatedInitializer(const InitializedEntity &Entity,
+                                  InitListExpr *IList, DesignatedInitExpr *DIE,
+                                  unsigned DesigIdx,
+                                  QualType &CurrentObjectType,
+                                  RecordDecl::field_iterator *NextField,
+                                  llvm::APSInt *NextElementIndex,
+                                  unsigned &Index,
+                                  InitListExpr *StructuredList,
+                                  unsigned &StructuredIndex,
+                                  bool FinishSubobjectInit,
+                                  bool TopLevelObject);
+  InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
+                                           QualType CurrentObjectType,
+                                           InitListExpr *StructuredList,
+                                           unsigned StructuredIndex,
+                                           SourceRange InitRange,
+                                           bool IsFullyOverwritten = false);
+  void UpdateStructuredListElement(InitListExpr *StructuredList,
+                                   unsigned &StructuredIndex,
+                                   Expr *expr);
+  int numArrayElements(QualType DeclType);
+  int numStructUnionElements(QualType DeclType);
+
+  static ExprResult PerformEmptyInit(Sema &SemaRef,
+                                     SourceLocation Loc,
+                                     const InitializedEntity &Entity,
+                                     bool VerifyOnly,
+                                     bool TreatUnavailableAsInvalid);
+
+  // Explanation on the "FillWithNoInit" mode:
+  //
+  // Assume we have the following definitions (Case#1):
+  // struct P { char x[6][6]; } xp = { .x[1] = "bar" };
+  // struct PP { struct P lp; } l = { .lp = xp, .lp.x[1][2] = 'f' };
+  //
+  // l.lp.x[1][0..1] should not be filled with implicit initializers because the
+  // "base" initializer "xp" will provide values for them; l.lp.x[1] will be "baf".
+  //
+  // But if we have (Case#2):
+  // struct PP l = { .lp = xp, .lp.x[1] = { [2] = 'f' } };
+  //
+  // l.lp.x[1][0..1] are implicitly initialized and do not use values from the
+  // "base" initializer; l.lp.x[1] will be "\0\0f\0\0\0".
+  //
+  // To distinguish Case#1 from Case#2, and also to avoid leaving many "holes"
+  // in the InitListExpr, the "holes" in Case#1 are filled not with empty
+  // initializers but with special "NoInitExpr" place holders, which tells the
+  // CodeGen not to generate any initializers for these parts.
+  void FillInEmptyInitForBase(unsigned Init, const CXXBaseSpecifier &Base,
+                              const InitializedEntity &ParentEntity,
+                              InitListExpr *ILE, bool &RequiresSecondPass,
+                              bool FillWithNoInit);
+  void FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
+                               const InitializedEntity &ParentEntity,
+                               InitListExpr *ILE, bool &RequiresSecondPass,
+                               bool FillWithNoInit = false);
+  void FillInEmptyInitializations(const InitializedEntity &Entity,
+                                  InitListExpr *ILE, bool &RequiresSecondPass,
+                                  InitListExpr *OuterILE, unsigned OuterIndex,
+                                  bool FillWithNoInit = false);
+  bool CheckFlexibleArrayInit(const InitializedEntity &Entity,
+                              Expr *InitExpr, FieldDecl *Field,
+                              bool TopLevelObject);
+  void CheckEmptyInitializable(const InitializedEntity &Entity,
+                               SourceLocation Loc);
+
+public:
+  InitListChecker(Sema &S, const InitializedEntity &Entity,
+                  InitListExpr *IL, QualType &T, bool VerifyOnly,
+                  bool TreatUnavailableAsInvalid);
+  bool HadError() { return hadError; }
+
+  // Retrieves the fully-structured initializer list used for
+  // semantic analysis and code generation.
+  InitListExpr *getFullyStructuredList() const { return FullyStructuredList; }
+};
+
+} // end anonymous namespace
+
+ExprResult InitListChecker::PerformEmptyInit(Sema &SemaRef,
+                                             SourceLocation Loc,
+                                             const InitializedEntity &Entity,
+                                             bool VerifyOnly,
+                                             bool TreatUnavailableAsInvalid) {
+  InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc,
+                                                            true);
+  MultiExprArg SubInit;
+  Expr *InitExpr;
+  InitListExpr DummyInitList(SemaRef.Context, Loc, None, Loc);
+
+  // C++ [dcl.init.aggr]p7:
+  //   If there are fewer initializer-clauses in the list than there are
+  //   members in the aggregate, then each member not explicitly initialized
+  //   ...
+  bool EmptyInitList = SemaRef.getLangOpts().CPlusPlus11 &&
+      Entity.getType()->getBaseElementTypeUnsafe()->isRecordType();
+  if (EmptyInitList) {
+    // C++1y / DR1070:
+    //   shall be initialized [...] from an empty initializer list.
+    //
+    // We apply the resolution of this DR to C++11 but not C++98, since C++98
+    // does not have useful semantics for initialization from an init list.
+    // We treat this as copy-initialization, because aggregate initialization
+    // always performs copy-initialization on its elements.
+    //
+    // Only do this if we're initializing a class type, to avoid filling in
+    // the initializer list where possible.
+    InitExpr = VerifyOnly ? &DummyInitList : new (SemaRef.Context)
+                   InitListExpr(SemaRef.Context, Loc, None, Loc);
+    InitExpr->setType(SemaRef.Context.VoidTy);
+    SubInit = InitExpr;
+    Kind = InitializationKind::CreateCopy(Loc, Loc);
+  } else {
+    // C++03:
+    //   shall be value-initialized.
+  }
+
+  InitializationSequence InitSeq(SemaRef, Entity, Kind, SubInit);
+  // libstdc++4.6 marks the vector default constructor as explicit in
+  // _GLIBCXX_DEBUG mode, so recover using the C++03 logic in that case.
+  // stlport does so too. Look for std::__debug for libstdc++, and for
+  // std:: for stlport.  This is effectively a compiler-side implementation of
+  // LWG2193.
+  if (!InitSeq && EmptyInitList && InitSeq.getFailureKind() ==
+          InitializationSequence::FK_ExplicitConstructor) {
+    OverloadCandidateSet::iterator Best;
+    OverloadingResult O =
+        InitSeq.getFailedCandidateSet()
+            .BestViableFunction(SemaRef, Kind.getLocation(), Best);
+    (void)O;
+    assert(O == OR_Success && "Inconsistent overload resolution");
+    CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
+    CXXRecordDecl *R = CtorDecl->getParent();
+
+    if (CtorDecl->getMinRequiredArguments() == 0 &&
+        CtorDecl->isExplicit() && R->getDeclName() &&
+        SemaRef.SourceMgr.isInSystemHeader(CtorDecl->getLocation())) {
+      bool IsInStd = false;
+      for (NamespaceDecl *ND = dyn_cast<NamespaceDecl>(R->getDeclContext());
+           ND && !IsInStd; ND = dyn_cast<NamespaceDecl>(ND->getParent())) {
+        if (SemaRef.getStdNamespace()->InEnclosingNamespaceSetOf(ND))
+          IsInStd = true;
+      }
+
+      if (IsInStd && llvm::StringSwitch<bool>(R->getName())
+              .Cases("basic_string", "deque", "forward_list", true)
+              .Cases("list", "map", "multimap", "multiset", true)
+              .Cases("priority_queue", "queue", "set", "stack", true)
+              .Cases("unordered_map", "unordered_set", "vector", true)
+              .Default(false)) {
+        InitSeq.InitializeFrom(
+            SemaRef, Entity,
+            InitializationKind::CreateValue(Loc, Loc, Loc, true),
+            MultiExprArg(), /*TopLevelOfInitList=*/false,
+            TreatUnavailableAsInvalid);
+        // Emit a warning for this.  System header warnings aren't shown
+        // by default, but people working on system headers should see it.
+        if (!VerifyOnly) {
+          SemaRef.Diag(CtorDecl->getLocation(),
+                       diag::warn_invalid_initializer_from_system_header);
+          if (Entity.getKind() == InitializedEntity::EK_Member)
+            SemaRef.Diag(Entity.getDecl()->getLocation(),
+                         diag::note_used_in_initialization_here);
+          else if (Entity.getKind() == InitializedEntity::EK_ArrayElement)
+            SemaRef.Diag(Loc, diag::note_used_in_initialization_here);
+        }
+      }
+    }
+  }
+  if (!InitSeq) {
+    if (!VerifyOnly) {
+      InitSeq.Diagnose(SemaRef, Entity, Kind, SubInit);
+      if (Entity.getKind() == InitializedEntity::EK_Member)
+        SemaRef.Diag(Entity.getDecl()->getLocation(),
+                     diag::note_in_omitted_aggregate_initializer)
+          << /*field*/1 << Entity.getDecl();
+      else if (Entity.getKind() == InitializedEntity::EK_ArrayElement) {
+        bool IsTrailingArrayNewMember =
+            Entity.getParent() &&
+            Entity.getParent()->isVariableLengthArrayNew();
+        SemaRef.Diag(Loc, diag::note_in_omitted_aggregate_initializer)
+          << (IsTrailingArrayNewMember ? 2 : /*array element*/0)
+          << Entity.getElementIndex();
+      }
+    }
+    return ExprError();
+  }
+
+  return VerifyOnly ? ExprResult(static_cast<Expr *>(nullptr))
+                    : InitSeq.Perform(SemaRef, Entity, Kind, SubInit);
+}
+
+void InitListChecker::CheckEmptyInitializable(const InitializedEntity &Entity,
+                                              SourceLocation Loc) {
+  assert(VerifyOnly &&
+         "CheckEmptyInitializable is only inteded for verification mode.");
+  if (PerformEmptyInit(SemaRef, Loc, Entity, /*VerifyOnly*/true,
+                       TreatUnavailableAsInvalid).isInvalid())
+    hadError = true;
+}
+
+void InitListChecker::FillInEmptyInitForBase(
+    unsigned Init, const CXXBaseSpecifier &Base,
+    const InitializedEntity &ParentEntity, InitListExpr *ILE,
+    bool &RequiresSecondPass, bool FillWithNoInit) {
+  assert(Init < ILE->getNumInits() && "should have been expanded");
+
+  InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
+      SemaRef.Context, &Base, false, &ParentEntity);
+
+  if (!ILE->getInit(Init)) {
+    ExprResult BaseInit =
+        FillWithNoInit
+            ? new (SemaRef.Context) NoInitExpr(Base.getType())
+            : PerformEmptyInit(SemaRef, ILE->getEndLoc(), BaseEntity,
+                               /*VerifyOnly*/ false, TreatUnavailableAsInvalid);
+    if (BaseInit.isInvalid()) {
+      hadError = true;
+      return;
+    }
+
+    ILE->setInit(Init, BaseInit.getAs<Expr>());
+  } else if (InitListExpr *InnerILE =
+                 dyn_cast<InitListExpr>(ILE->getInit(Init))) {
+    FillInEmptyInitializations(BaseEntity, InnerILE, RequiresSecondPass,
+                               ILE, Init, FillWithNoInit);
+  } else if (DesignatedInitUpdateExpr *InnerDIUE =
+               dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init))) {
+    FillInEmptyInitializations(BaseEntity, InnerDIUE->getUpdater(),
+                               RequiresSecondPass, ILE, Init,
+                               /*FillWithNoInit =*/true);
+  }
+}
+
+void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
+                                        const InitializedEntity &ParentEntity,
+                                              InitListExpr *ILE,
+                                              bool &RequiresSecondPass,
+                                              bool FillWithNoInit) {
+  SourceLocation Loc = ILE->getEndLoc();
+  unsigned NumInits = ILE->getNumInits();
+  InitializedEntity MemberEntity
+    = InitializedEntity::InitializeMember(Field, &ParentEntity);
+
+  if (const RecordType *RType = ILE->getType()->getAs<RecordType>())
+    if (!RType->getDecl()->isUnion())
+      assert(Init < NumInits && "This ILE should have been expanded");
+
+  if (Init >= NumInits || !ILE->getInit(Init)) {
+    if (FillWithNoInit) {
+      Expr *Filler = new (SemaRef.Context) NoInitExpr(Field->getType());
+      if (Init < NumInits)
+        ILE->setInit(Init, Filler);
+      else
+        ILE->updateInit(SemaRef.Context, Init, Filler);
+      return;
+    }
+    // C++1y [dcl.init.aggr]p7:
+    //   If there are fewer initializer-clauses in the list than there are
+    //   members in the aggregate, then each member not explicitly initialized
+    //   shall be initialized from its brace-or-equal-initializer [...]
+    if (Field->hasInClassInitializer()) {
+      ExprResult DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field);
+      if (DIE.isInvalid()) {
+        hadError = true;
+        return;
+      }
+      SemaRef.checkInitializerLifetime(MemberEntity, DIE.get());
+      if (Init < NumInits)
+        ILE->setInit(Init, DIE.get());
+      else {
+        ILE->updateInit(SemaRef.Context, Init, DIE.get());
+        RequiresSecondPass = true;
+      }
+      return;
+    }
+
+    if (Field->getType()->isReferenceType()) {
+      // C++ [dcl.init.aggr]p9:
+      //   If an incomplete or empty initializer-list leaves a
+      //   member of reference type uninitialized, the program is
+      //   ill-formed.
+      SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized)
+        << Field->getType()
+        << ILE->getSyntacticForm()->getSourceRange();
+      SemaRef.Diag(Field->getLocation(),
+                   diag::note_uninit_reference_member);
+      hadError = true;
+      return;
+    }
+
+    ExprResult MemberInit = PerformEmptyInit(SemaRef, Loc, MemberEntity,
+                                             /*VerifyOnly*/false,
+                                             TreatUnavailableAsInvalid);
+    if (MemberInit.isInvalid()) {
+      hadError = true;
+      return;
+    }
+
+    if (hadError) {
+      // Do nothing
+    } else if (Init < NumInits) {
+      ILE->setInit(Init, MemberInit.getAs<Expr>());
+    } else if (!isa<ImplicitValueInitExpr>(MemberInit.get())) {
+      // Empty initialization requires a constructor call, so
+      // extend the initializer list to include the constructor
+      // call and make a note that we'll need to take another pass
+      // through the initializer list.
+      ILE->updateInit(SemaRef.Context, Init, MemberInit.getAs<Expr>());
+      RequiresSecondPass = true;
+    }
+  } else if (InitListExpr *InnerILE
+               = dyn_cast<InitListExpr>(ILE->getInit(Init)))
+    FillInEmptyInitializations(MemberEntity, InnerILE,
+                               RequiresSecondPass, ILE, Init, FillWithNoInit);
+  else if (DesignatedInitUpdateExpr *InnerDIUE
+               = dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init)))
+    FillInEmptyInitializations(MemberEntity, InnerDIUE->getUpdater(),
+                               RequiresSecondPass, ILE, Init,
+                               /*FillWithNoInit =*/true);
+}
+
+/// Recursively replaces NULL values within the given initializer list
+/// with expressions that perform value-initialization of the
+/// appropriate type, and finish off the InitListExpr formation.
+void
+InitListChecker::FillInEmptyInitializations(const InitializedEntity &Entity,
+                                            InitListExpr *ILE,
+                                            bool &RequiresSecondPass,
+                                            InitListExpr *OuterILE,
+                                            unsigned OuterIndex,
+                                            bool FillWithNoInit) {
+  assert((ILE->getType() != SemaRef.Context.VoidTy) &&
+         "Should not have void type");
+
+  // If this is a nested initializer list, we might have changed its contents
+  // (and therefore some of its properties, such as instantiation-dependence)
+  // while filling it in. Inform the outer initializer list so that its state
+  // can be updated to match.
+  // FIXME: We should fully build the inner initializers before constructing
+  // the outer InitListExpr instead of mutating AST nodes after they have
+  // been used as subexpressions of other nodes.
+  struct UpdateOuterILEWithUpdatedInit {
+    InitListExpr *Outer;
+    unsigned OuterIndex;
+    ~UpdateOuterILEWithUpdatedInit() {
+      if (Outer)
+        Outer->setInit(OuterIndex, Outer->getInit(OuterIndex));
+    }
+  } UpdateOuterRAII = {OuterILE, OuterIndex};
+
+  // A transparent ILE is not performing aggregate initialization and should
+  // not be filled in.
+  if (ILE->isTransparent())
+    return;
+
+  if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
+    const RecordDecl *RDecl = RType->getDecl();
+    if (RDecl->isUnion() && ILE->getInitializedFieldInUnion())
+      FillInEmptyInitForField(0, ILE->getInitializedFieldInUnion(),
+                              Entity, ILE, RequiresSecondPass, FillWithNoInit);
+    else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) &&
+             cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) {
+      for (auto *Field : RDecl->fields()) {
+        if (Field->hasInClassInitializer()) {
+          FillInEmptyInitForField(0, Field, Entity, ILE, RequiresSecondPass,
+                                  FillWithNoInit);
+          break;
+        }
+      }
+    } else {
+      // The fields beyond ILE->getNumInits() are default initialized, so in
+      // order to leave them uninitialized, the ILE is expanded and the extra
+      // fields are then filled with NoInitExpr.
+      unsigned NumElems = numStructUnionElements(ILE->getType());
+      if (RDecl->hasFlexibleArrayMember())
+        ++NumElems;
+      if (ILE->getNumInits() < NumElems)
+        ILE->resizeInits(SemaRef.Context, NumElems);
+
+      unsigned Init = 0;
+
+      if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RDecl)) {
+        for (auto &Base : CXXRD->bases()) {
+          if (hadError)
+            return;
+
+          FillInEmptyInitForBase(Init, Base, Entity, ILE, RequiresSecondPass,
+                                 FillWithNoInit);
+          ++Init;
+        }
+      }
+
+      for (auto *Field : RDecl->fields()) {
+        if (Field->isUnnamedBitfield())
+          continue;
+
+        if (hadError)
+          return;
+
+        FillInEmptyInitForField(Init, Field, Entity, ILE, RequiresSecondPass,
+                                FillWithNoInit);
+        if (hadError)
+          return;
+
+        ++Init;
+
+        // Only look at the first initialization of a union.
+        if (RDecl->isUnion())
+          break;
+      }
+    }
+
+    return;
+  }
+
+  QualType ElementType;
+
+  InitializedEntity ElementEntity = Entity;
+  unsigned NumInits = ILE->getNumInits();
+  unsigned NumElements = NumInits;
+  if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) {
+    ElementType = AType->getElementType();
+    if (const auto *CAType = dyn_cast<ConstantArrayType>(AType))
+      NumElements = CAType->getSize().getZExtValue();
+    // For an array new with an unknown bound, ask for one additional element
+    // in order to populate the array filler.
+    if (Entity.isVariableLengthArrayNew())
+      ++NumElements;
+    ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
+                                                         0, Entity);
+  } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) {
+    ElementType = VType->getElementType();
+    NumElements = VType->getNumElements();
+    ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
+                                                         0, Entity);
+  } else
+    ElementType = ILE->getType();
+
+  for (unsigned Init = 0; Init != NumElements; ++Init) {
+    if (hadError)
+      return;
+
+    if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement ||
+        ElementEntity.getKind() == InitializedEntity::EK_VectorElement)
+      ElementEntity.setElementIndex(Init);
+
+    if (Init >= NumInits && ILE->hasArrayFiller())
+      return;
+
+    Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : nullptr);
+    if (!InitExpr && Init < NumInits && ILE->hasArrayFiller())
+      ILE->setInit(Init, ILE->getArrayFiller());
+    else if (!InitExpr && !ILE->hasArrayFiller()) {
+      Expr *Filler = nullptr;
+
+      if (FillWithNoInit)
+        Filler = new (SemaRef.Context) NoInitExpr(ElementType);
+      else {
+        ExprResult ElementInit =
+            PerformEmptyInit(SemaRef, ILE->getEndLoc(), ElementEntity,
+                             /*VerifyOnly*/ false, TreatUnavailableAsInvalid);
+        if (ElementInit.isInvalid()) {
+          hadError = true;
+          return;
+        }
+
+        Filler = ElementInit.getAs<Expr>();
+      }
+
+      if (hadError) {
+        // Do nothing
+      } else if (Init < NumInits) {
+        // For arrays, just set the expression used for value-initialization
+        // of the "holes" in the array.
+        if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement)
+          ILE->setArrayFiller(Filler);
+        else
+          ILE->setInit(Init, Filler);
+      } else {
+        // For arrays, just set the expression used for value-initialization
+        // of the rest of elements and exit.
+        if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) {
+          ILE->setArrayFiller(Filler);
+          return;
+        }
+
+        if (!isa<ImplicitValueInitExpr>(Filler) && !isa<NoInitExpr>(Filler)) {
+          // Empty initialization requires a constructor call, so
+          // extend the initializer list to include the constructor
+          // call and make a note that we'll need to take another pass
+          // through the initializer list.
+          ILE->updateInit(SemaRef.Context, Init, Filler);
+          RequiresSecondPass = true;
+        }
+      }
+    } else if (InitListExpr *InnerILE
+                 = dyn_cast_or_null<InitListExpr>(InitExpr))
+      FillInEmptyInitializations(ElementEntity, InnerILE, RequiresSecondPass,
+                                 ILE, Init, FillWithNoInit);
+    else if (DesignatedInitUpdateExpr *InnerDIUE
+                 = dyn_cast_or_null<DesignatedInitUpdateExpr>(InitExpr))
+      FillInEmptyInitializations(ElementEntity, InnerDIUE->getUpdater(),
+                                 RequiresSecondPass, ILE, Init,
+                                 /*FillWithNoInit =*/true);
+  }
+}
+
+InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity,
+                                 InitListExpr *IL, QualType &T,
+                                 bool VerifyOnly,
+                                 bool TreatUnavailableAsInvalid)
+  : SemaRef(S), VerifyOnly(VerifyOnly),
+    TreatUnavailableAsInvalid(TreatUnavailableAsInvalid) {
+  // FIXME: Check that IL isn't already the semantic form of some other
+  // InitListExpr. If it is, we'd create a broken AST.
+
+  hadError = false;
+
+  FullyStructuredList =
+      getStructuredSubobjectInit(IL, 0, T, nullptr, 0, IL->getSourceRange());
+  CheckExplicitInitList(Entity, IL, T, FullyStructuredList,
+                        /*TopLevelObject=*/true);
+
+  if (!hadError && !VerifyOnly) {
+    bool RequiresSecondPass = false;
+    FillInEmptyInitializations(Entity, FullyStructuredList, RequiresSecondPass,
+                               /*OuterILE=*/nullptr, /*OuterIndex=*/0);
+    if (RequiresSecondPass && !hadError)
+      FillInEmptyInitializations(Entity, FullyStructuredList,
+                                 RequiresSecondPass, nullptr, 0);
+  }
+}
+
+int InitListChecker::numArrayElements(QualType DeclType) {
+  // FIXME: use a proper constant
+  int maxElements = 0x7FFFFFFF;
+  if (const ConstantArrayType *CAT =
+        SemaRef.Context.getAsConstantArrayType(DeclType)) {
+    maxElements = static_cast<int>(CAT->getSize().getZExtValue());
+  }
+  return maxElements;
+}
+
+int InitListChecker::numStructUnionElements(QualType DeclType) {
+  RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl();
+  int InitializableMembers = 0;
+  if (auto *CXXRD = dyn_cast<CXXRecordDecl>(structDecl))
+    InitializableMembers += CXXRD->getNumBases();
+  for (const auto *Field : structDecl->fields())
+    if (!Field->isUnnamedBitfield())
+      ++InitializableMembers;
+
+  if (structDecl->isUnion())
+    return std::min(InitializableMembers, 1);
+  return InitializableMembers - structDecl->hasFlexibleArrayMember();
+}
+
+/// Determine whether Entity is an entity for which it is idiomatic to elide
+/// the braces in aggregate initialization.
+static bool isIdiomaticBraceElisionEntity(const InitializedEntity &Entity) {
+  // Recursive initialization of the one and only field within an aggregate
+  // class is considered idiomatic. This case arises in particular for
+  // initialization of std::array, where the C++ standard suggests the idiom of
+  //
+  //   std::array<T, N> arr = {1, 2, 3};
+  //
+  // (where std::array is an aggregate struct containing a single array field.
+
+  // FIXME: Should aggregate initialization of a struct with a single
+  // base class and no members also suppress the warning?
+  if (Entity.getKind() != InitializedEntity::EK_Member || !Entity.getParent())
+    return false;
+
+  auto *ParentRD =
+      Entity.getParent()->getType()->castAs<RecordType>()->getDecl();
+  if (CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(ParentRD))
+    if (CXXRD->getNumBases())
+      return false;
+
+  auto FieldIt = ParentRD->field_begin();
+  assert(FieldIt != ParentRD->field_end() &&
+         "no fields but have initializer for member?");
+  return ++FieldIt == ParentRD->field_end();
+}
+
+/// Check whether the range of the initializer \p ParentIList from element
+/// \p Index onwards can be used to initialize an object of type \p T. Update
+/// \p Index to indicate how many elements of the list were consumed.
+///
+/// This also fills in \p StructuredList, from element \p StructuredIndex
+/// onwards, with the fully-braced, desugared form of the initialization.
+void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity,
+                                            InitListExpr *ParentIList,
+                                            QualType T, unsigned &Index,
+                                            InitListExpr *StructuredList,
+                                            unsigned &StructuredIndex) {
+  int maxElements = 0;
+
+  if (T->isArrayType())
+    maxElements = numArrayElements(T);
+  else if (T->isRecordType())
+    maxElements = numStructUnionElements(T);
+  else if (T->isVectorType())
+    maxElements = T->getAs<VectorType>()->getNumElements();
+  else
+    llvm_unreachable("CheckImplicitInitList(): Illegal type");
+
+  if (maxElements == 0) {
+    if (!VerifyOnly)
+      SemaRef.Diag(ParentIList->getInit(Index)->getBeginLoc(),
+                   diag::err_implicit_empty_initializer);
+    ++Index;
+    hadError = true;
+    return;
+  }
+
+  // Build a structured initializer list corresponding to this subobject.
+  InitListExpr *StructuredSubobjectInitList = getStructuredSubobjectInit(
+      ParentIList, Index, T, StructuredList, StructuredIndex,
+      SourceRange(ParentIList->getInit(Index)->getBeginLoc(),
+                  ParentIList->getSourceRange().getEnd()));
+  unsigned StructuredSubobjectInitIndex = 0;
+
+  // Check the element types and build the structural subobject.
+  unsigned StartIndex = Index;
+  CheckListElementTypes(Entity, ParentIList, T,
+                        /*SubobjectIsDesignatorContext=*/false, Index,
+                        StructuredSubobjectInitList,
+                        StructuredSubobjectInitIndex);
+
+  if (!VerifyOnly) {
+    StructuredSubobjectInitList->setType(T);
+
+    unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1);
+    // Update the structured sub-object initializer so that it's ending
+    // range corresponds with the end of the last initializer it used.
+    if (EndIndex < ParentIList->getNumInits() &&
+        ParentIList->getInit(EndIndex)) {
+      SourceLocation EndLoc
+        = ParentIList->getInit(EndIndex)->getSourceRange().getEnd();
+      StructuredSubobjectInitList->setRBraceLoc(EndLoc);
+    }
+
+    // Complain about missing braces.
+    if ((T->isArrayType() || T->isRecordType()) &&
+        !ParentIList->isIdiomaticZeroInitializer(SemaRef.getLangOpts()) &&
+        !isIdiomaticBraceElisionEntity(Entity)) {
+      SemaRef.Diag(StructuredSubobjectInitList->getBeginLoc(),
+                   diag::warn_missing_braces)
+          << StructuredSubobjectInitList->getSourceRange()
+          << FixItHint::CreateInsertion(
+                 StructuredSubobjectInitList->getBeginLoc(), "{")
+          << FixItHint::CreateInsertion(
+                 SemaRef.getLocForEndOfToken(
+                     StructuredSubobjectInitList->getEndLoc()),
+                 "}");
+    }
+
+    // Warn if this type won't be an aggregate in future versions of C++.
+    auto *CXXRD = T->getAsCXXRecordDecl();
+    if (CXXRD && CXXRD->hasUserDeclaredConstructor()) {
+      SemaRef.Diag(StructuredSubobjectInitList->getBeginLoc(),
+                   diag::warn_cxx2a_compat_aggregate_init_with_ctors)
+          << StructuredSubobjectInitList->getSourceRange() << T;
+    }
+  }
+}
+
+/// Warn that \p Entity was of scalar type and was initialized by a
+/// single-element braced initializer list.
+static void warnBracedScalarInit(Sema &S, const InitializedEntity &Entity,
+                                 SourceRange Braces) {
+  // Don't warn during template instantiation. If the initialization was
+  // non-dependent, we warned during the initial parse; otherwise, the
+  // type might not be scalar in some uses of the template.
+  if (S.inTemplateInstantiation())
+    return;
+
+  unsigned DiagID = 0;
+
+  switch (Entity.getKind()) {
+  case InitializedEntity::EK_VectorElement:
+  case InitializedEntity::EK_ComplexElement:
+  case InitializedEntity::EK_ArrayElement:
+  case InitializedEntity::EK_Parameter:
+  case InitializedEntity::EK_Parameter_CF_Audited:
+  case InitializedEntity::EK_Result:
+    // Extra braces here are suspicious.
+    DiagID = diag::warn_braces_around_scalar_init;
+    break;
+
+  case InitializedEntity::EK_Member:
+    // Warn on aggregate initialization but not on ctor init list or
+    // default member initializer.
+    if (Entity.getParent())
+      DiagID = diag::warn_braces_around_scalar_init;
+    break;
+
+  case InitializedEntity::EK_Variable:
+  case InitializedEntity::EK_LambdaCapture:
+    // No warning, might be direct-list-initialization.
+    // FIXME: Should we warn for copy-list-initialization in these cases?
+    break;
+
+  case InitializedEntity::EK_New:
+  case InitializedEntity::EK_Temporary:
+  case InitializedEntity::EK_CompoundLiteralInit:
+    // No warning, braces are part of the syntax of the underlying construct.
+    break;
+
+  case InitializedEntity::EK_RelatedResult:
+    // No warning, we already warned when initializing the result.
+    break;
+
+  case InitializedEntity::EK_Exception:
+  case InitializedEntity::EK_Base:
+  case InitializedEntity::EK_Delegating:
+  case InitializedEntity::EK_BlockElement:
+  case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
+  case InitializedEntity::EK_Binding:
+  case InitializedEntity::EK_StmtExprResult:
+    llvm_unreachable("unexpected braced scalar init");
+  }
+
+  if (DiagID) {
+    S.Diag(Braces.getBegin(), DiagID)
+      << Braces
+      << FixItHint::CreateRemoval(Braces.getBegin())
+      << FixItHint::CreateRemoval(Braces.getEnd());
+  }
+}
+
+/// Check whether the initializer \p IList (that was written with explicit
+/// braces) can be used to initialize an object of type \p T.
+///
+/// This also fills in \p StructuredList with the fully-braced, desugared
+/// form of the initialization.
+void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity,
+                                            InitListExpr *IList, QualType &T,
+                                            InitListExpr *StructuredList,
+                                            bool TopLevelObject) {
+  if (!VerifyOnly) {
+    SyntacticToSemantic[IList] = StructuredList;
+    StructuredList->setSyntacticForm(IList);
+  }
+
+  unsigned Index = 0, StructuredIndex = 0;
+  CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true,
+                        Index, StructuredList, StructuredIndex, TopLevelObject);
+  if (!VerifyOnly) {
+    QualType ExprTy = T;
+    if (!ExprTy->isArrayType())
+      ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context);
+    IList->setType(ExprTy);
+    StructuredList->setType(ExprTy);
+  }
+  if (hadError)
+    return;
+
+  if (Index < IList->getNumInits()) {
+    // We have leftover initializers
+    if (VerifyOnly) {
+      if (SemaRef.getLangOpts().CPlusPlus ||
+          (SemaRef.getLangOpts().OpenCL &&
+           IList->getType()->isVectorType())) {
+        hadError = true;
+      }
+      return;
+    }
+
+    if (StructuredIndex == 1 &&
+        IsStringInit(StructuredList->getInit(0), T, SemaRef.Context) ==
+            SIF_None) {
+      unsigned DK = diag::ext_excess_initializers_in_char_array_initializer;
+      if (SemaRef.getLangOpts().CPlusPlus) {
+        DK = diag::err_excess_initializers_in_char_array_initializer;
+        hadError = true;
+      }
+      // Special-case
+      SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
+          << IList->getInit(Index)->getSourceRange();
+    } else if (!T->isIncompleteType()) {
+      // Don't complain for incomplete types, since we'll get an error
+      // elsewhere
+      QualType CurrentObjectType = StructuredList->getType();
+      int initKind =
+        CurrentObjectType->isArrayType()? 0 :
+        CurrentObjectType->isVectorType()? 1 :
+        CurrentObjectType->isScalarType()? 2 :
+        CurrentObjectType->isUnionType()? 3 :
+        4;
+
+      unsigned DK = diag::ext_excess_initializers;
+      if (SemaRef.getLangOpts().CPlusPlus) {
+        DK = diag::err_excess_initializers;
+        hadError = true;
+      }
+      if (SemaRef.getLangOpts().OpenCL && initKind == 1) {
+        DK = diag::err_excess_initializers;
+        hadError = true;
+      }
+
+      SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
+          << initKind << IList->getInit(Index)->getSourceRange();
+    }
+  }
+
+  if (!VerifyOnly) {
+    if (T->isScalarType() && IList->getNumInits() == 1 &&
+        !isa<InitListExpr>(IList->getInit(0)))
+      warnBracedScalarInit(SemaRef, Entity, IList->getSourceRange());
+
+    // Warn if this is a class type that won't be an aggregate in future
+    // versions of C++.
+    auto *CXXRD = T->getAsCXXRecordDecl();
+    if (CXXRD && CXXRD->hasUserDeclaredConstructor()) {
+      // Don't warn if there's an equivalent default constructor that would be
+      // used instead.
+      bool HasEquivCtor = false;
+      if (IList->getNumInits() == 0) {
+        auto *CD = SemaRef.LookupDefaultConstructor(CXXRD);
+        HasEquivCtor = CD && !CD->isDeleted();
+      }
+
+      if (!HasEquivCtor) {
+        SemaRef.Diag(IList->getBeginLoc(),
+                     diag::warn_cxx2a_compat_aggregate_init_with_ctors)
+            << IList->getSourceRange() << T;
+      }
+    }
+  }
+}
+
+void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity,
+                                            InitListExpr *IList,
+                                            QualType &DeclType,
+                                            bool SubobjectIsDesignatorContext,
+                                            unsigned &Index,
+                                            InitListExpr *StructuredList,
+                                            unsigned &StructuredIndex,
+                                            bool TopLevelObject) {
+  if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) {
+    // Explicitly braced initializer for complex type can be real+imaginary
+    // parts.
+    CheckComplexType(Entity, IList, DeclType, Index,
+                     StructuredList, StructuredIndex);
+  } else if (DeclType->isScalarType()) {
+    CheckScalarType(Entity, IList, DeclType, Index,
+                    StructuredList, StructuredIndex);
+  } else if (DeclType->isVectorType()) {
+    CheckVectorType(Entity, IList, DeclType, Index,
+                    StructuredList, StructuredIndex);
+  } else if (DeclType->isRecordType()) {
+    assert(DeclType->isAggregateType() &&
+           "non-aggregate records should be handed in CheckSubElementType");
+    RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
+    auto Bases =
+        CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
+                                        CXXRecordDecl::base_class_iterator());
+    if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
+      Bases = CXXRD->bases();
+    CheckStructUnionTypes(Entity, IList, DeclType, Bases, RD->field_begin(),
+                          SubobjectIsDesignatorContext, Index, StructuredList,
+                          StructuredIndex, TopLevelObject);
+  } else if (DeclType->isArrayType()) {
+    llvm::APSInt Zero(
+                    SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()),
+                    false);
+    CheckArrayType(Entity, IList, DeclType, Zero,
+                   SubobjectIsDesignatorContext, Index,
+                   StructuredList, StructuredIndex);
+  } else if (DeclType->isVoidType() || DeclType->isFunctionType()) {
+    // This type is invalid, issue a diagnostic.
+    ++Index;
+    if (!VerifyOnly)
+      SemaRef.Diag(IList->getBeginLoc(), diag::err_illegal_initializer_type)
+          << DeclType;
+    hadError = true;
+  } else if (DeclType->isReferenceType()) {
+    CheckReferenceType(Entity, IList, DeclType, Index,
+                       StructuredList, StructuredIndex);
+  } else if (DeclType->isObjCObjectType()) {
+    if (!VerifyOnly)
+      SemaRef.Diag(IList->getBeginLoc(), diag::err_init_objc_class) << DeclType;
+    hadError = true;
+  } else if (DeclType->isOCLIntelSubgroupAVCType()) {
+    // Checks for scalar type are sufficient for these types too.
+    CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
+                    StructuredIndex);
+  } else {
+    if (!VerifyOnly)
+      SemaRef.Diag(IList->getBeginLoc(), diag::err_illegal_initializer_type)
+          << DeclType;
+    hadError = true;
+  }
+}
+
+void InitListChecker::CheckSubElementType(const InitializedEntity &Entity,
+                                          InitListExpr *IList,
+                                          QualType ElemType,
+                                          unsigned &Index,
+                                          InitListExpr *StructuredList,
+                                          unsigned &StructuredIndex) {
+  Expr *expr = IList->getInit(Index);
+
+  if (ElemType->isReferenceType())
+    return CheckReferenceType(Entity, IList, ElemType, Index,
+                              StructuredList, StructuredIndex);
+
+  if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) {
+    if (SubInitList->getNumInits() == 1 &&
+        IsStringInit(SubInitList->getInit(0), ElemType, SemaRef.Context) ==
+        SIF_None) {
+      expr = SubInitList->getInit(0);
+    } else if (!SemaRef.getLangOpts().CPlusPlus) {
+      InitListExpr *InnerStructuredList
+        = getStructuredSubobjectInit(IList, Index, ElemType,
+                                     StructuredList, StructuredIndex,
+                                     SubInitList->getSourceRange(), true);
+      CheckExplicitInitList(Entity, SubInitList, ElemType,
+                            InnerStructuredList);
+
+      if (!hadError && !VerifyOnly) {
+        bool RequiresSecondPass = false;
+        FillInEmptyInitializations(Entity, InnerStructuredList,
+                                   RequiresSecondPass, StructuredList,
+                                   StructuredIndex);
+        if (RequiresSecondPass && !hadError)
+          FillInEmptyInitializations(Entity, InnerStructuredList,
+                                     RequiresSecondPass, StructuredList,
+                                     StructuredIndex);
+      }
+      ++StructuredIndex;
+      ++Index;
+      return;
+    }
+    // C++ initialization is handled later.
+  } else if (isa<ImplicitValueInitExpr>(expr)) {
+    // This happens during template instantiation when we see an InitListExpr
+    // that we've already checked once.
+    assert(SemaRef.Context.hasSameType(expr->getType(), ElemType) &&
+           "found implicit initialization for the wrong type");
+    if (!VerifyOnly)
+      UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
+    ++Index;
+    return;
+  }
+
+  if (SemaRef.getLangOpts().CPlusPlus) {
+    // C++ [dcl.init.aggr]p2:
+    //   Each member is copy-initialized from the corresponding
+    //   initializer-clause.
+
+    // FIXME: Better EqualLoc?
+    InitializationKind Kind =
+        InitializationKind::CreateCopy(expr->getBeginLoc(), SourceLocation());
+
+    // Vector elements can be initialized from other vectors in which case
+    // we need initialization entity with a type of a vector (and not a vector
+    // element!) initializing multiple vector elements.
+    auto TmpEntity =
+        (ElemType->isExtVectorType() && !Entity.getType()->isExtVectorType())
+            ? InitializedEntity::InitializeTemporary(ElemType)
+            : Entity;
+
+    InitializationSequence Seq(SemaRef, TmpEntity, Kind, expr,
+                               /*TopLevelOfInitList*/ true);
+
+    // C++14 [dcl.init.aggr]p13:
+    //   If the assignment-expression can initialize a member, the member is
+    //   initialized. Otherwise [...] brace elision is assumed
+    //
+    // Brace elision is never performed if the element is not an
+    // assignment-expression.
+    if (Seq || isa<InitListExpr>(expr)) {
+      if (!VerifyOnly) {
+        ExprResult Result = Seq.Perform(SemaRef, TmpEntity, Kind, expr);
+        if (Result.isInvalid())
+          hadError = true;
+
+        UpdateStructuredListElement(StructuredList, StructuredIndex,
+                                    Result.getAs<Expr>());
+      } else if (!Seq)
+        hadError = true;
+      ++Index;
+      return;
+    }
+
+    // Fall through for subaggregate initialization
+  } else if (ElemType->isScalarType() || ElemType->isAtomicType()) {
+    // FIXME: Need to handle atomic aggregate types with implicit init lists.
+    return CheckScalarType(Entity, IList, ElemType, Index,
+                           StructuredList, StructuredIndex);
+  } else if (const ArrayType *arrayType =
+                 SemaRef.Context.getAsArrayType(ElemType)) {
+    // arrayType can be incomplete if we're initializing a flexible
+    // array member.  There's nothing we can do with the completed
+    // type here, though.
+
+    if (IsStringInit(expr, arrayType, SemaRef.Context) == SIF_None) {
+      if (!VerifyOnly) {
+        CheckStringInit(expr, ElemType, arrayType, SemaRef);
+        UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
+      }
+      ++Index;
+      return;
+    }
+
+    // Fall through for subaggregate initialization.
+
+  } else {
+    assert((ElemType->isRecordType() || ElemType->isVectorType() ||
+            ElemType->isOpenCLSpecificType()) && "Unexpected type");
+
+    // C99 6.7.8p13:
+    //
+    //   The initializer for a structure or union object that has
+    //   automatic storage duration shall be either an initializer
+    //   list as described below, or a single expression that has
+    //   compatible structure or union type. In the latter case, the
+    //   initial value of the object, including unnamed members, is
+    //   that of the expression.
+    ExprResult ExprRes = expr;
+    if (SemaRef.CheckSingleAssignmentConstraints(
+            ElemType, ExprRes, !VerifyOnly) != Sema::Incompatible) {
+      if (ExprRes.isInvalid())
+        hadError = true;
+      else {
+        ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.get());
+          if (ExprRes.isInvalid())
+            hadError = true;
+      }
+      UpdateStructuredListElement(StructuredList, StructuredIndex,
+                                  ExprRes.getAs<Expr>());
+      ++Index;
+      return;
+    }
+    ExprRes.get();
+    // Fall through for subaggregate initialization
+  }
+
+  // C++ [dcl.init.aggr]p12:
+  //
+  //   [...] Otherwise, if the member is itself a non-empty
+  //   subaggregate, brace elision is assumed and the initializer is
+  //   considered for the initialization of the first member of
+  //   the subaggregate.
+  // OpenCL vector initializer is handled elsewhere.
+  if ((!SemaRef.getLangOpts().OpenCL && ElemType->isVectorType()) ||
+      ElemType->isAggregateType()) {
+    CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList,
+                          StructuredIndex);
+    ++StructuredIndex;
+  } else {
+    if (!VerifyOnly) {
+      // We cannot initialize this element, so let
+      // PerformCopyInitialization produce the appropriate diagnostic.
+      SemaRef.PerformCopyInitialization(Entity, SourceLocation(), expr,
+                                        /*TopLevelOfInitList=*/true);
+    }
+    hadError = true;
+    ++Index;
+    ++StructuredIndex;
+  }
+}
+
+void InitListChecker::CheckComplexType(const InitializedEntity &Entity,
+                                       InitListExpr *IList, QualType DeclType,
+                                       unsigned &Index,
+                                       InitListExpr *StructuredList,
+                                       unsigned &StructuredIndex) {
+  assert(Index == 0 && "Index in explicit init list must be zero");
+
+  // As an extension, clang supports complex initializers, which initialize
+  // a complex number component-wise.  When an explicit initializer list for
+  // a complex number contains two two initializers, this extension kicks in:
+  // it exepcts the initializer list to contain two elements convertible to
+  // the element type of the complex type. The first element initializes
+  // the real part, and the second element intitializes the imaginary part.
+
+  if (IList->getNumInits() != 2)
+    return CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
+                           StructuredIndex);
+
+  // This is an extension in C.  (The builtin _Complex type does not exist
+  // in the C++ standard.)
+  if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly)
+    SemaRef.Diag(IList->getBeginLoc(), diag::ext_complex_component_init)
+        << IList->getSourceRange();
+
+  // Initialize the complex number.
+  QualType elementType = DeclType->getAs<ComplexType>()->getElementType();
+  InitializedEntity ElementEntity =
+    InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
+
+  for (unsigned i = 0; i < 2; ++i) {
+    ElementEntity.setElementIndex(Index);
+    CheckSubElementType(ElementEntity, IList, elementType, Index,
+                        StructuredList, StructuredIndex);
+  }
+}
+
+void InitListChecker::CheckScalarType(const InitializedEntity &Entity,
+                                      InitListExpr *IList, QualType DeclType,
+                                      unsigned &Index,
+                                      InitListExpr *StructuredList,
+                                      unsigned &StructuredIndex) {
+  if (Index >= IList->getNumInits()) {
+    if (!VerifyOnly)
+      SemaRef.Diag(IList->getBeginLoc(),
+                   SemaRef.getLangOpts().CPlusPlus11
+                       ? diag::warn_cxx98_compat_empty_scalar_initializer
+                       : diag::err_empty_scalar_initializer)
+          << IList->getSourceRange();
+    hadError = !SemaRef.getLangOpts().CPlusPlus11;
+    ++Index;
+    ++StructuredIndex;
+    return;
+  }
+
+  Expr *expr = IList->getInit(Index);
+  if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) {
+    // FIXME: This is invalid, and accepting it causes overload resolution
+    // to pick the wrong overload in some corner cases.
+    if (!VerifyOnly)
+      SemaRef.Diag(SubIList->getBeginLoc(),
+                   diag::ext_many_braces_around_scalar_init)
+          << SubIList->getSourceRange();
+
+    CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList,
+                    StructuredIndex);
+    return;
+  } else if (isa<DesignatedInitExpr>(expr)) {
+    if (!VerifyOnly)
+      SemaRef.Diag(expr->getBeginLoc(), diag::err_designator_for_scalar_init)
+          << DeclType << expr->getSourceRange();
+    hadError = true;
+    ++Index;
+    ++StructuredIndex;
+    return;
+  }
+
+  if (VerifyOnly) {
+    if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
+      hadError = true;
+    ++Index;
+    return;
+  }
+
+  ExprResult Result =
+      SemaRef.PerformCopyInitialization(Entity, expr->getBeginLoc(), expr,
+                                        /*TopLevelOfInitList=*/true);
+
+  Expr *ResultExpr = nullptr;
+
+  if (Result.isInvalid())
+    hadError = true; // types weren't compatible.
+  else {
+    ResultExpr = Result.getAs<Expr>();
+
+    if (ResultExpr != expr) {
+      // The type was promoted, update initializer list.
+      IList->setInit(Index, ResultExpr);
+    }
+  }
+  if (hadError)
+    ++StructuredIndex;
+  else
+    UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
+  ++Index;
+}
+
+void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
+                                         InitListExpr *IList, QualType DeclType,
+                                         unsigned &Index,
+                                         InitListExpr *StructuredList,
+                                         unsigned &StructuredIndex) {
+  if (Index >= IList->getNumInits()) {
+    // FIXME: It would be wonderful if we could point at the actual member. In
+    // general, it would be useful to pass location information down the stack,
+    // so that we know the location (or decl) of the "current object" being
+    // initialized.
+    if (!VerifyOnly)
+      SemaRef.Diag(IList->getBeginLoc(),
+                   diag::err_init_reference_member_uninitialized)
+          << DeclType << IList->getSourceRange();
+    hadError = true;
+    ++Index;
+    ++StructuredIndex;
+    return;
+  }
+
+  Expr *expr = IList->getInit(Index);
+  if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus11) {
+    if (!VerifyOnly)
+      SemaRef.Diag(IList->getBeginLoc(), diag::err_init_non_aggr_init_list)
+          << DeclType << IList->getSourceRange();
+    hadError = true;
+    ++Index;
+    ++StructuredIndex;
+    return;
+  }
+
+  if (VerifyOnly) {
+    if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
+      hadError = true;
+    ++Index;
+    return;
+  }
+
+  ExprResult Result =
+      SemaRef.PerformCopyInitialization(Entity, expr->getBeginLoc(), expr,
+                                        /*TopLevelOfInitList=*/true);
+
+  if (Result.isInvalid())
+    hadError = true;
+
+  expr = Result.getAs<Expr>();
+  IList->setInit(Index, expr);
+
+  if (hadError)
+    ++StructuredIndex;
+  else
+    UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
+  ++Index;
+}
+
+void InitListChecker::CheckVectorType(const InitializedEntity &Entity,
+                                      InitListExpr *IList, QualType DeclType,
+                                      unsigned &Index,
+                                      InitListExpr *StructuredList,
+                                      unsigned &StructuredIndex) {
+  const VectorType *VT = DeclType->getAs<VectorType>();
+  unsigned maxElements = VT->getNumElements();
+  unsigned numEltsInit = 0;
+  QualType elementType = VT->getElementType();
+
+  if (Index >= IList->getNumInits()) {
+    // Make sure the element type can be value-initialized.
+    if (VerifyOnly)
+      CheckEmptyInitializable(
+          InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
+          IList->getEndLoc());
+    return;
+  }
+
+  if (!SemaRef.getLangOpts().OpenCL) {
+    // If the initializing element is a vector, try to copy-initialize
+    // instead of breaking it apart (which is doomed to failure anyway).
+    Expr *Init = IList->getInit(Index);
+    if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) {
+      if (VerifyOnly) {
+        if (!SemaRef.CanPerformCopyInitialization(Entity, Init))
+          hadError = true;
+        ++Index;
+        return;
+      }
+
+      ExprResult Result =
+          SemaRef.PerformCopyInitialization(Entity, Init->getBeginLoc(), Init,
+                                            /*TopLevelOfInitList=*/true);
+
+      Expr *ResultExpr = nullptr;
+      if (Result.isInvalid())
+        hadError = true; // types weren't compatible.
+      else {
+        ResultExpr = Result.getAs<Expr>();
+
+        if (ResultExpr != Init) {
+          // The type was promoted, update initializer list.
+          IList->setInit(Index, ResultExpr);
+        }
+      }
+      if (hadError)
+        ++StructuredIndex;
+      else
+        UpdateStructuredListElement(StructuredList, StructuredIndex,
+                                    ResultExpr);
+      ++Index;
+      return;
+    }
+
+    InitializedEntity ElementEntity =
+      InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
+
+    for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) {
+      // Don't attempt to go past the end of the init list
+      if (Index >= IList->getNumInits()) {
+        if (VerifyOnly)
+          CheckEmptyInitializable(ElementEntity, IList->getEndLoc());
+        break;
+      }
+
+      ElementEntity.setElementIndex(Index);
+      CheckSubElementType(ElementEntity, IList, elementType, Index,
+                          StructuredList, StructuredIndex);
+    }
+
+    if (VerifyOnly)
+      return;
+
+    bool isBigEndian = SemaRef.Context.getTargetInfo().isBigEndian();
+    const VectorType *T = Entity.getType()->getAs<VectorType>();
+    if (isBigEndian && (T->getVectorKind() == VectorType::NeonVector ||
+                        T->getVectorKind() == VectorType::NeonPolyVector)) {
+      // The ability to use vector initializer lists is a GNU vector extension
+      // and is unrelated to the NEON intrinsics in arm_neon.h. On little
+      // endian machines it works fine, however on big endian machines it
+      // exhibits surprising behaviour:
+      //
+      //   uint32x2_t x = {42, 64};
+      //   return vget_lane_u32(x, 0); // Will return 64.
+      //
+      // Because of this, explicitly call out that it is non-portable.
+      //
+      SemaRef.Diag(IList->getBeginLoc(),
+                   diag::warn_neon_vector_initializer_non_portable);
+
+      const char *typeCode;
+      unsigned typeSize = SemaRef.Context.getTypeSize(elementType);
+
+      if (elementType->isFloatingType())
+        typeCode = "f";
+      else if (elementType->isSignedIntegerType())
+        typeCode = "s";
+      else if (elementType->isUnsignedIntegerType())
+        typeCode = "u";
+      else
+        llvm_unreachable("Invalid element type!");
+
+      SemaRef.Diag(IList->getBeginLoc(),
+                   SemaRef.Context.getTypeSize(VT) > 64
+                       ? diag::note_neon_vector_initializer_non_portable_q
+                       : diag::note_neon_vector_initializer_non_portable)
+          << typeCode << typeSize;
+    }
+
+    return;
+  }
+
+  InitializedEntity ElementEntity =
+    InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
+
+  // OpenCL initializers allows vectors to be constructed from vectors.
+  for (unsigned i = 0; i < maxElements; ++i) {
+    // Don't attempt to go past the end of the init list
+    if (Index >= IList->getNumInits())
+      break;
+
+    ElementEntity.setElementIndex(Index);
+
+    QualType IType = IList->getInit(Index)->getType();
+    if (!IType->isVectorType()) {
+      CheckSubElementType(ElementEntity, IList, elementType, Index,
+                          StructuredList, StructuredIndex);
+      ++numEltsInit;
+    } else {
+      QualType VecType;
+      const VectorType *IVT = IType->getAs<VectorType>();
+      unsigned numIElts = IVT->getNumElements();
+
+      if (IType->isExtVectorType())
+        VecType = SemaRef.Context.getExtVectorType(elementType, numIElts);
+      else
+        VecType = SemaRef.Context.getVectorType(elementType, numIElts,
+                                                IVT->getVectorKind());
+      CheckSubElementType(ElementEntity, IList, VecType, Index,
+                          StructuredList, StructuredIndex);
+      numEltsInit += numIElts;
+    }
+  }
+
+  // OpenCL requires all elements to be initialized.
+  if (numEltsInit != maxElements) {
+    if (!VerifyOnly)
+      SemaRef.Diag(IList->getBeginLoc(),
+                   diag::err_vector_incorrect_num_initializers)
+          << (numEltsInit < maxElements) << maxElements << numEltsInit;
+    hadError = true;
+  }
+}
+
+/// Check if the type of a class element has an accessible destructor, and marks
+/// it referenced. Returns true if we shouldn't form a reference to the
+/// destructor.
+///
+/// Aggregate initialization requires a class element's destructor be
+/// accessible per 11.6.1 [dcl.init.aggr]:
+///
+/// The destructor for each element of class type is potentially invoked
+/// (15.4 [class.dtor]) from the context where the aggregate initialization
+/// occurs.
+static bool checkDestructorReference(QualType ElementType, SourceLocation Loc,
+                                     Sema &SemaRef) {
+  auto *CXXRD = ElementType->getAsCXXRecordDecl();
+  if (!CXXRD)
+    return false;
+
+  CXXDestructorDecl *Destructor = SemaRef.LookupDestructor(CXXRD);
+  SemaRef.CheckDestructorAccess(Loc, Destructor,
+                                SemaRef.PDiag(diag::err_access_dtor_temp)
+                                << ElementType);
+  SemaRef.MarkFunctionReferenced(Loc, Destructor);
+  return SemaRef.DiagnoseUseOfDecl(Destructor, Loc);
+}
+
+void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
+                                     InitListExpr *IList, QualType &DeclType,
+                                     llvm::APSInt elementIndex,
+                                     bool SubobjectIsDesignatorContext,
+                                     unsigned &Index,
+                                     InitListExpr *StructuredList,
+                                     unsigned &StructuredIndex) {
+  const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType);
+
+  if (!VerifyOnly) {
+    if (checkDestructorReference(arrayType->getElementType(),
+                                 IList->getEndLoc(), SemaRef)) {
+      hadError = true;
+      return;
+    }
+  }
+
+  // Check for the special-case of initializing an array with a string.
+  if (Index < IList->getNumInits()) {
+    if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) ==
+        SIF_None) {
+      // We place the string literal directly into the resulting
+      // initializer list. This is the only place where the structure
+      // of the structured initializer list doesn't match exactly,
+      // because doing so would involve allocating one character
+      // constant for each string.
+      if (!VerifyOnly) {
+        CheckStringInit(IList->getInit(Index), DeclType, arrayType, SemaRef);
+        UpdateStructuredListElement(StructuredList, StructuredIndex,
+                                    IList->getInit(Index));
+        StructuredList->resizeInits(SemaRef.Context, StructuredIndex);
+      }
+      ++Index;
+      return;
+    }
+  }
+  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) {
+    // Check for VLAs; in standard C it would be possible to check this
+    // earlier, but I don't know where clang accepts VLAs (gcc accepts
+    // them in all sorts of strange places).
+    if (!VerifyOnly)
+      SemaRef.Diag(VAT->getSizeExpr()->getBeginLoc(),
+                   diag::err_variable_object_no_init)
+          << VAT->getSizeExpr()->getSourceRange();
+    hadError = true;
+    ++Index;
+    ++StructuredIndex;
+    return;
+  }
+
+  // We might know the maximum number of elements in advance.
+  llvm::APSInt maxElements(elementIndex.getBitWidth(),
+                           elementIndex.isUnsigned());
+  bool maxElementsKnown = false;
+  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) {
+    maxElements = CAT->getSize();
+    elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth());
+    elementIndex.setIsUnsigned(maxElements.isUnsigned());
+    maxElementsKnown = true;
+  }
+
+  QualType elementType = arrayType->getElementType();
+  while (Index < IList->getNumInits()) {
+    Expr *Init = IList->getInit(Index);
+    if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
+      // If we're not the subobject that matches up with the '{' for
+      // the designator, we shouldn't be handling the
+      // designator. Return immediately.
+      if (!SubobjectIsDesignatorContext)
+        return;
+
+      // Handle this designated initializer. elementIndex will be
+      // updated to be the next array element we'll initialize.
+      if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
+                                     DeclType, nullptr, &elementIndex, Index,
+                                     StructuredList, StructuredIndex, true,
+                                     false)) {
+        hadError = true;
+        continue;
+      }
+
+      if (elementIndex.getBitWidth() > maxElements.getBitWidth())
+        maxElements = maxElements.extend(elementIndex.getBitWidth());
+      else if (elementIndex.getBitWidth() < maxElements.getBitWidth())
+        elementIndex = elementIndex.extend(maxElements.getBitWidth());
+      elementIndex.setIsUnsigned(maxElements.isUnsigned());
+
+      // If the array is of incomplete type, keep track of the number of
+      // elements in the initializer.
+      if (!maxElementsKnown && elementIndex > maxElements)
+        maxElements = elementIndex;
+
+      continue;
+    }
+
+    // If we know the maximum number of elements, and we've already
+    // hit it, stop consuming elements in the initializer list.
+    if (maxElementsKnown && elementIndex == maxElements)
+      break;
+
+    InitializedEntity ElementEntity =
+      InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex,
+                                           Entity);
+    // Check this element.
+    CheckSubElementType(ElementEntity, IList, elementType, Index,
+                        StructuredList, StructuredIndex);
+    ++elementIndex;
+
+    // If the array is of incomplete type, keep track of the number of
+    // elements in the initializer.
+    if (!maxElementsKnown && elementIndex > maxElements)
+      maxElements = elementIndex;
+  }
+  if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) {
+    // If this is an incomplete array type, the actual type needs to
+    // be calculated here.
+    llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned());
+    if (maxElements == Zero && !Entity.isVariableLengthArrayNew()) {
+      // Sizing an array implicitly to zero is not allowed by ISO C,
+      // but is supported by GNU.
+      SemaRef.Diag(IList->getBeginLoc(), diag::ext_typecheck_zero_array_size);
+    }
+
+    DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements,
+                                                     ArrayType::Normal, 0);
+  }
+  if (!hadError && VerifyOnly) {
+    // If there are any members of the array that get value-initialized, check
+    // that is possible. That happens if we know the bound and don't have
+    // enough elements, or if we're performing an array new with an unknown
+    // bound.
+    // FIXME: This needs to detect holes left by designated initializers too.
+    if ((maxElementsKnown && elementIndex < maxElements) ||
+        Entity.isVariableLengthArrayNew())
+      CheckEmptyInitializable(
+          InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
+          IList->getEndLoc());
+  }
+}
+
+bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity,
+                                             Expr *InitExpr,
+                                             FieldDecl *Field,
+                                             bool TopLevelObject) {
+  // Handle GNU flexible array initializers.
+  unsigned FlexArrayDiag;
+  if (isa<InitListExpr>(InitExpr) &&
+      cast<InitListExpr>(InitExpr)->getNumInits() == 0) {
+    // Empty flexible array init always allowed as an extension
+    FlexArrayDiag = diag::ext_flexible_array_init;
+  } else if (SemaRef.getLangOpts().CPlusPlus) {
+    // Disallow flexible array init in C++; it is not required for gcc
+    // compatibility, and it needs work to IRGen correctly in general.
+    FlexArrayDiag = diag::err_flexible_array_init;
+  } else if (!TopLevelObject) {
+    // Disallow flexible array init on non-top-level object
+    FlexArrayDiag = diag::err_flexible_array_init;
+  } else if (Entity.getKind() != InitializedEntity::EK_Variable) {
+    // Disallow flexible array init on anything which is not a variable.
+    FlexArrayDiag = diag::err_flexible_array_init;
+  } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) {
+    // Disallow flexible array init on local variables.
+    FlexArrayDiag = diag::err_flexible_array_init;
+  } else {
+    // Allow other cases.
+    FlexArrayDiag = diag::ext_flexible_array_init;
+  }
+
+  if (!VerifyOnly) {
+    SemaRef.Diag(InitExpr->getBeginLoc(), FlexArrayDiag)
+        << InitExpr->getBeginLoc();
+    SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
+      << Field;
+  }
+
+  return FlexArrayDiag != diag::ext_flexible_array_init;
+}
+
+void InitListChecker::CheckStructUnionTypes(
+    const InitializedEntity &Entity, InitListExpr *IList, QualType DeclType,
+    CXXRecordDecl::base_class_range Bases, RecordDecl::field_iterator Field,
+    bool SubobjectIsDesignatorContext, unsigned &Index,
+    InitListExpr *StructuredList, unsigned &StructuredIndex,
+    bool TopLevelObject) {
+  RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl();
+
+  // If the record is invalid, some of it's members are invalid. To avoid
+  // confusion, we forgo checking the intializer for the entire record.
+  if (structDecl->isInvalidDecl()) {
+    // Assume it was supposed to consume a single initializer.
+    ++Index;
+    hadError = true;
+    return;
+  }
+
+  if (DeclType->isUnionType() && IList->getNumInits() == 0) {
+    RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
+
+    if (!VerifyOnly)
+      for (FieldDecl *FD : RD->fields()) {
+        QualType ET = SemaRef.Context.getBaseElementType(FD->getType());
+        if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
+          hadError = true;
+          return;
+        }
+      }
+
+    // If there's a default initializer, use it.
+    if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->hasInClassInitializer()) {
+      if (VerifyOnly)
+        return;
+      for (RecordDecl::field_iterator FieldEnd = RD->field_end();
+           Field != FieldEnd; ++Field) {
+        if (Field->hasInClassInitializer()) {
+          StructuredList->setInitializedFieldInUnion(*Field);
+          // FIXME: Actually build a CXXDefaultInitExpr?
+          return;
+        }
+      }
+    }
+
+    // Value-initialize the first member of the union that isn't an unnamed
+    // bitfield.
+    for (RecordDecl::field_iterator FieldEnd = RD->field_end();
+         Field != FieldEnd; ++Field) {
+      if (!Field->isUnnamedBitfield()) {
+        if (VerifyOnly)
+          CheckEmptyInitializable(
+              InitializedEntity::InitializeMember(*Field, &Entity),
+              IList->getEndLoc());
+        else
+          StructuredList->setInitializedFieldInUnion(*Field);
+        break;
+      }
+    }
+    return;
+  }
+
+  bool InitializedSomething = false;
+
+  // If we have any base classes, they are initialized prior to the fields.
+  for (auto &Base : Bases) {
+    Expr *Init = Index < IList->getNumInits() ? IList->getInit(Index) : nullptr;
+
+    // Designated inits always initialize fields, so if we see one, all
+    // remaining base classes have no explicit initializer.
+    if (Init && isa<DesignatedInitExpr>(Init))
+      Init = nullptr;
+
+    SourceLocation InitLoc = Init ? Init->getBeginLoc() : IList->getEndLoc();
+    InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
+        SemaRef.Context, &Base, false, &Entity);
+    if (Init) {
+      CheckSubElementType(BaseEntity, IList, Base.getType(), Index,
+                          StructuredList, StructuredIndex);
+      InitializedSomething = true;
+    } else if (VerifyOnly) {
+      CheckEmptyInitializable(BaseEntity, InitLoc);
+    }
+
+    if (!VerifyOnly)
+      if (checkDestructorReference(Base.getType(), InitLoc, SemaRef)) {
+        hadError = true;
+        return;
+      }
+  }
+
+  // If structDecl is a forward declaration, this loop won't do
+  // anything except look at designated initializers; That's okay,
+  // because an error should get printed out elsewhere. It might be
+  // worthwhile to skip over the rest of the initializer, though.
+  RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
+  RecordDecl::field_iterator FieldEnd = RD->field_end();
+  bool CheckForMissingFields =
+    !IList->isIdiomaticZeroInitializer(SemaRef.getLangOpts());
+  bool HasDesignatedInit = false;
+
+  while (Index < IList->getNumInits()) {
+    Expr *Init = IList->getInit(Index);
+    SourceLocation InitLoc = Init->getBeginLoc();
+
+    if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
+      // If we're not the subobject that matches up with the '{' for
+      // the designator, we shouldn't be handling the
+      // designator. Return immediately.
+      if (!SubobjectIsDesignatorContext)
+        return;
+
+      HasDesignatedInit = true;
+
+      // Handle this designated initializer. Field will be updated to
+      // the next field that we'll be initializing.
+      if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
+                                     DeclType, &Field, nullptr, Index,
+                                     StructuredList, StructuredIndex,
+                                     true, TopLevelObject))
+        hadError = true;
+      else if (!VerifyOnly) {
+        // Find the field named by the designated initializer.
+        RecordDecl::field_iterator F = RD->field_begin();
+        while (std::next(F) != Field)
+          ++F;
+        QualType ET = SemaRef.Context.getBaseElementType(F->getType());
+        if (checkDestructorReference(ET, InitLoc, SemaRef)) {
+          hadError = true;
+          return;
+        }
+      }
+
+      InitializedSomething = true;
+
+      // Disable check for missing fields when designators are used.
+      // This matches gcc behaviour.
+      CheckForMissingFields = false;
+      continue;
+    }
+
+    if (Field == FieldEnd) {
+      // We've run out of fields. We're done.
+      break;
+    }
+
+    // We've already initialized a member of a union. We're done.
+    if (InitializedSomething && DeclType->isUnionType())
+      break;
+
+    // If we've hit the flexible array member at the end, we're done.
+    if (Field->getType()->isIncompleteArrayType())
+      break;
+
+    if (Field->isUnnamedBitfield()) {
+      // Don't initialize unnamed bitfields, e.g. "int : 20;"
+      ++Field;
+      continue;
+    }
+
+    // Make sure we can use this declaration.
+    bool InvalidUse;
+    if (VerifyOnly)
+      InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
+    else
+      InvalidUse = SemaRef.DiagnoseUseOfDecl(
+          *Field, IList->getInit(Index)->getBeginLoc());
+    if (InvalidUse) {
+      ++Index;
+      ++Field;
+      hadError = true;
+      continue;
+    }
+
+    if (!VerifyOnly) {
+      QualType ET = SemaRef.Context.getBaseElementType(Field->getType());
+      if (checkDestructorReference(ET, InitLoc, SemaRef)) {
+        hadError = true;
+        return;
+      }
+    }
+
+    InitializedEntity MemberEntity =
+      InitializedEntity::InitializeMember(*Field, &Entity);
+    CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
+                        StructuredList, StructuredIndex);
+    InitializedSomething = true;
+
+    if (DeclType->isUnionType() && !VerifyOnly) {
+      // Initialize the first field within the union.
+      StructuredList->setInitializedFieldInUnion(*Field);
+    }
+
+    ++Field;
+  }
+
+  // Emit warnings for missing struct field initializers.
+  if (!VerifyOnly && InitializedSomething && CheckForMissingFields &&
+      Field != FieldEnd && !Field->getType()->isIncompleteArrayType() &&
+      !DeclType->isUnionType()) {
+    // It is possible we have one or more unnamed bitfields remaining.
+    // Find first (if any) named field and emit warning.
+    for (RecordDecl::field_iterator it = Field, end = RD->field_end();
+         it != end; ++it) {
+      if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) {
+        SemaRef.Diag(IList->getSourceRange().getEnd(),
+                     diag::warn_missing_field_initializers) << *it;
+        break;
+      }
+    }
+  }
+
+  // Check that any remaining fields can be value-initialized.
+  if (VerifyOnly && Field != FieldEnd && !DeclType->isUnionType() &&
+      !Field->getType()->isIncompleteArrayType()) {
+    // FIXME: Should check for holes left by designated initializers too.
+    for (; Field != FieldEnd && !hadError; ++Field) {
+      if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer())
+        CheckEmptyInitializable(
+            InitializedEntity::InitializeMember(*Field, &Entity),
+            IList->getEndLoc());
+    }
+  }
+
+  // Check that the types of the remaining fields have accessible destructors.
+  if (!VerifyOnly) {
+    // If the initializer expression has a designated initializer, check the
+    // elements for which a designated initializer is not provided too.
+    RecordDecl::field_iterator I = HasDesignatedInit ? RD->field_begin()
+                                                     : Field;
+    for (RecordDecl::field_iterator E = RD->field_end(); I != E; ++I) {
+      QualType ET = SemaRef.Context.getBaseElementType(I->getType());
+      if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
+        hadError = true;
+        return;
+      }
+    }
+  }
+
+  if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() ||
+      Index >= IList->getNumInits())
+    return;
+
+  if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field,
+                             TopLevelObject)) {
+    hadError = true;
+    ++Index;
+    return;
+  }
+
+  InitializedEntity MemberEntity =
+    InitializedEntity::InitializeMember(*Field, &Entity);
+
+  if (isa<InitListExpr>(IList->getInit(Index)))
+    CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
+                        StructuredList, StructuredIndex);
+  else
+    CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index,
+                          StructuredList, StructuredIndex);
+}
+
+/// Expand a field designator that refers to a member of an
+/// anonymous struct or union into a series of field designators that
+/// refers to the field within the appropriate subobject.
+///
+static void ExpandAnonymousFieldDesignator(Sema &SemaRef,
+                                           DesignatedInitExpr *DIE,
+                                           unsigned DesigIdx,
+                                           IndirectFieldDecl *IndirectField) {
+  typedef DesignatedInitExpr::Designator Designator;
+
+  // Build the replacement designators.
+  SmallVector<Designator, 4> Replacements;
+  for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(),
+       PE = IndirectField->chain_end(); PI != PE; ++PI) {
+    if (PI + 1 == PE)
+      Replacements.push_back(Designator((IdentifierInfo *)nullptr,
+                                    DIE->getDesignator(DesigIdx)->getDotLoc(),
+                                DIE->getDesignator(DesigIdx)->getFieldLoc()));
+    else
+      Replacements.push_back(Designator((IdentifierInfo *)nullptr,
+                                        SourceLocation(), SourceLocation()));
+    assert(isa<FieldDecl>(*PI));
+    Replacements.back().setField(cast<FieldDecl>(*PI));
+  }
+
+  // Expand the current designator into the set of replacement
+  // designators, so we have a full subobject path down to where the
+  // member of the anonymous struct/union is actually stored.
+  DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0],
+                        &Replacements[0] + Replacements.size());
+}
+
+static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef,
+                                                   DesignatedInitExpr *DIE) {
+  unsigned NumIndexExprs = DIE->getNumSubExprs() - 1;
+  SmallVector<Expr*, 4> IndexExprs(NumIndexExprs);
+  for (unsigned I = 0; I < NumIndexExprs; ++I)
+    IndexExprs[I] = DIE->getSubExpr(I + 1);
+  return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators(),
+                                    IndexExprs,
+                                    DIE->getEqualOrColonLoc(),
+                                    DIE->usesGNUSyntax(), DIE->getInit());
+}
+
+namespace {
+
+// Callback to only accept typo corrections that are for field members of
+// the given struct or union.
+class FieldInitializerValidatorCCC final : public CorrectionCandidateCallback {
+ public:
+  explicit FieldInitializerValidatorCCC(RecordDecl *RD)
+      : Record(RD) {}
+
+  bool ValidateCandidate(const TypoCorrection &candidate) override {
+    FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>();
+    return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record);
+  }
+
+  std::unique_ptr<CorrectionCandidateCallback> clone() override {
+    return llvm::make_unique<FieldInitializerValidatorCCC>(*this);
+  }
+
+ private:
+  RecordDecl *Record;
+};
+
+} // end anonymous namespace
+
+/// Check the well-formedness of a C99 designated initializer.
+///
+/// Determines whether the designated initializer @p DIE, which
+/// resides at the given @p Index within the initializer list @p
+/// IList, is well-formed for a current object of type @p DeclType
+/// (C99 6.7.8). The actual subobject that this designator refers to
+/// within the current subobject is returned in either
+/// @p NextField or @p NextElementIndex (whichever is appropriate).
+///
+/// @param IList  The initializer list in which this designated
+/// initializer occurs.
+///
+/// @param DIE The designated initializer expression.
+///
+/// @param DesigIdx  The index of the current designator.
+///
+/// @param CurrentObjectType The type of the "current object" (C99 6.7.8p17),
+/// into which the designation in @p DIE should refer.
+///
+/// @param NextField  If non-NULL and the first designator in @p DIE is
+/// a field, this will be set to the field declaration corresponding
+/// to the field named by the designator.
+///
+/// @param NextElementIndex  If non-NULL and the first designator in @p
+/// DIE is an array designator or GNU array-range designator, this
+/// will be set to the last index initialized by this designator.
+///
+/// @param Index  Index into @p IList where the designated initializer
+/// @p DIE occurs.
+///
+/// @param StructuredList  The initializer list expression that
+/// describes all of the subobject initializers in the order they'll
+/// actually be initialized.
+///
+/// @returns true if there was an error, false otherwise.
+bool
+InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity,
+                                            InitListExpr *IList,
+                                            DesignatedInitExpr *DIE,
+                                            unsigned DesigIdx,
+                                            QualType &CurrentObjectType,
+                                          RecordDecl::field_iterator *NextField,
+                                            llvm::APSInt *NextElementIndex,
+                                            unsigned &Index,
+                                            InitListExpr *StructuredList,
+                                            unsigned &StructuredIndex,
+                                            bool FinishSubobjectInit,
+                                            bool TopLevelObject) {
+  if (DesigIdx == DIE->size()) {
+    // Check the actual initialization for the designated object type.
+    bool prevHadError = hadError;
+
+    // Temporarily remove the designator expression from the
+    // initializer list that the child calls see, so that we don't try
+    // to re-process the designator.
+    unsigned OldIndex = Index;
+    IList->setInit(OldIndex, DIE->getInit());
+
+    CheckSubElementType(Entity, IList, CurrentObjectType, Index,
+                        StructuredList, StructuredIndex);
+
+    // Restore the designated initializer expression in the syntactic
+    // form of the initializer list.
+    if (IList->getInit(OldIndex) != DIE->getInit())
+      DIE->setInit(IList->getInit(OldIndex));
+    IList->setInit(OldIndex, DIE);
+
+    return hadError && !prevHadError;
+  }
+
+  DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx);
+  bool IsFirstDesignator = (DesigIdx == 0);
+  if (!VerifyOnly) {
+    assert((IsFirstDesignator || StructuredList) &&
+           "Need a non-designated initializer list to start from");
+
+    // Determine the structural initializer list that corresponds to the
+    // current subobject.
+    if (IsFirstDesignator)
+      StructuredList = SyntacticToSemantic.lookup(IList);
+    else {
+      Expr *ExistingInit = StructuredIndex < StructuredList->getNumInits() ?
+          StructuredList->getInit(StructuredIndex) : nullptr;
+      if (!ExistingInit && StructuredList->hasArrayFiller())
+        ExistingInit = StructuredList->getArrayFiller();
+
+      if (!ExistingInit)
+        StructuredList = getStructuredSubobjectInit(
+            IList, Index, CurrentObjectType, StructuredList, StructuredIndex,
+            SourceRange(D->getBeginLoc(), DIE->getEndLoc()));
+      else if (InitListExpr *Result = dyn_cast<InitListExpr>(ExistingInit))
+        StructuredList = Result;
+      else {
+        if (DesignatedInitUpdateExpr *E =
+                dyn_cast<DesignatedInitUpdateExpr>(ExistingInit))
+          StructuredList = E->getUpdater();
+        else {
+          DesignatedInitUpdateExpr *DIUE = new (SemaRef.Context)
+              DesignatedInitUpdateExpr(SemaRef.Context, D->getBeginLoc(),
+                                       ExistingInit, DIE->getEndLoc());
+          StructuredList->updateInit(SemaRef.Context, StructuredIndex, DIUE);
+          StructuredList = DIUE->getUpdater();
+        }
+
+        // We need to check on source range validity because the previous
+        // initializer does not have to be an explicit initializer. e.g.,
+        //
+        // struct P { int a, b; };
+        // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
+        //
+        // There is an overwrite taking place because the first braced initializer
+        // list "{ .a = 2 }" already provides value for .p.b (which is zero).
+        if (ExistingInit->getSourceRange().isValid()) {
+          // We are creating an initializer list that initializes the
+          // subobjects of the current object, but there was already an
+          // initialization that completely initialized the current
+          // subobject, e.g., by a compound literal:
+          //
+          // struct X { int a, b; };
+          // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
+          //
+          // Here, xs[0].a == 0 and xs[0].b == 3, since the second,
+          // designated initializer re-initializes the whole
+          // subobject [0], overwriting previous initializers.
+          SemaRef.Diag(D->getBeginLoc(),
+                       diag::warn_subobject_initializer_overrides)
+              << SourceRange(D->getBeginLoc(), DIE->getEndLoc());
+
+          SemaRef.Diag(ExistingInit->getBeginLoc(),
+                       diag::note_previous_initializer)
+              << /*FIXME:has side effects=*/0 << ExistingInit->getSourceRange();
+        }
+      }
+    }
+    assert(StructuredList && "Expected a structured initializer list");
+  }
+
+  if (D->isFieldDesignator()) {
+    // C99 6.7.8p7:
+    //
+    //   If a designator has the form
+    //
+    //      . identifier
+    //
+    //   then the current object (defined below) shall have
+    //   structure or union type and the identifier shall be the
+    //   name of a member of that type.
+    const RecordType *RT = CurrentObjectType->getAs<RecordType>();
+    if (!RT) {
+      SourceLocation Loc = D->getDotLoc();
+      if (Loc.isInvalid())
+        Loc = D->getFieldLoc();
+      if (!VerifyOnly)
+        SemaRef.Diag(Loc, diag::err_field_designator_non_aggr)
+          << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType;
+      ++Index;
+      return true;
+    }
+
+    FieldDecl *KnownField = D->getField();
+    if (!KnownField) {
+      IdentifierInfo *FieldName = D->getFieldName();
+      DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName);
+      for (NamedDecl *ND : Lookup) {
+        if (auto *FD = dyn_cast<FieldDecl>(ND)) {
+          KnownField = FD;
+          break;
+        }
+        if (auto *IFD = dyn_cast<IndirectFieldDecl>(ND)) {
+          // In verify mode, don't modify the original.
+          if (VerifyOnly)
+            DIE = CloneDesignatedInitExpr(SemaRef, DIE);
+          ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IFD);
+          D = DIE->getDesignator(DesigIdx);
+          KnownField = cast<FieldDecl>(*IFD->chain_begin());
+          break;
+        }
+      }
+      if (!KnownField) {
+        if (VerifyOnly) {
+          ++Index;
+          return true;  // No typo correction when just trying this out.
+        }
+
+        // Name lookup found something, but it wasn't a field.
+        if (!Lookup.empty()) {
+          SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield)
+            << FieldName;
+          SemaRef.Diag(Lookup.front()->getLocation(),
+                       diag::note_field_designator_found);
+          ++Index;
+          return true;
+        }
+
+        // Name lookup didn't find anything.
+        // Determine whether this was a typo for another field name.
+        FieldInitializerValidatorCCC CCC(RT->getDecl());
+        if (TypoCorrection Corrected = SemaRef.CorrectTypo(
+                DeclarationNameInfo(FieldName, D->getFieldLoc()),
+                Sema::LookupMemberName, /*Scope=*/nullptr, /*SS=*/nullptr, CCC,
+                Sema::CTK_ErrorRecovery, RT->getDecl())) {
+          SemaRef.diagnoseTypo(
+              Corrected,
+              SemaRef.PDiag(diag::err_field_designator_unknown_suggest)
+                << FieldName << CurrentObjectType);
+          KnownField = Corrected.getCorrectionDeclAs<FieldDecl>();
+          hadError = true;
+        } else {
+          // Typo correction didn't find anything.
+          SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown)
+            << FieldName << CurrentObjectType;
+          ++Index;
+          return true;
+        }
+      }
+    }
+
+    unsigned FieldIndex = 0;
+
+    if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
+      FieldIndex = CXXRD->getNumBases();
+
+    for (auto *FI : RT->getDecl()->fields()) {
+      if (FI->isUnnamedBitfield())
+        continue;
+      if (declaresSameEntity(KnownField, FI)) {
+        KnownField = FI;
+        break;
+      }
+      ++FieldIndex;
+    }
+
+    RecordDecl::field_iterator Field =
+        RecordDecl::field_iterator(DeclContext::decl_iterator(KnownField));
+
+    // All of the fields of a union are located at the same place in
+    // the initializer list.
+    if (RT->getDecl()->isUnion()) {
+      FieldIndex = 0;
+      if (!VerifyOnly) {
+        FieldDecl *CurrentField = StructuredList->getInitializedFieldInUnion();
+        if (CurrentField && !declaresSameEntity(CurrentField, *Field)) {
+          assert(StructuredList->getNumInits() == 1
+                 && "A union should never have more than one initializer!");
+
+          Expr *ExistingInit = StructuredList->getInit(0);
+          if (ExistingInit) {
+            // We're about to throw away an initializer, emit warning.
+            SemaRef.Diag(D->getFieldLoc(),
+                         diag::warn_initializer_overrides)
+              << D->getSourceRange();
+            SemaRef.Diag(ExistingInit->getBeginLoc(),
+                         diag::note_previous_initializer)
+                << /*FIXME:has side effects=*/0
+                << ExistingInit->getSourceRange();
+          }
+
+          // remove existing initializer
+          StructuredList->resizeInits(SemaRef.Context, 0);
+          StructuredList->setInitializedFieldInUnion(nullptr);
+        }
+
+        StructuredList->setInitializedFieldInUnion(*Field);
+      }
+    }
+
+    // Make sure we can use this declaration.
+    bool InvalidUse;
+    if (VerifyOnly)
+      InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
+    else
+      InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc());
+    if (InvalidUse) {
+      ++Index;
+      return true;
+    }
+
+    if (!VerifyOnly) {
+      // Update the designator with the field declaration.
+      D->setField(*Field);
+
+      // Make sure that our non-designated initializer list has space
+      // for a subobject corresponding to this field.
+      if (FieldIndex >= StructuredList->getNumInits())
+        StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1);
+    }
+
+    // This designator names a flexible array member.
+    if (Field->getType()->isIncompleteArrayType()) {
+      bool Invalid = false;
+      if ((DesigIdx + 1) != DIE->size()) {
+        // We can't designate an object within the flexible array
+        // member (because GCC doesn't allow it).
+        if (!VerifyOnly) {
+          DesignatedInitExpr::Designator *NextD
+            = DIE->getDesignator(DesigIdx + 1);
+          SemaRef.Diag(NextD->getBeginLoc(),
+                       diag::err_designator_into_flexible_array_member)
+              << SourceRange(NextD->getBeginLoc(), DIE->getEndLoc());
+          SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
+            << *Field;
+        }
+        Invalid = true;
+      }
+
+      if (!hadError && !isa<InitListExpr>(DIE->getInit()) &&
+          !isa<StringLiteral>(DIE->getInit())) {
+        // The initializer is not an initializer list.
+        if (!VerifyOnly) {
+          SemaRef.Diag(DIE->getInit()->getBeginLoc(),
+                       diag::err_flexible_array_init_needs_braces)
+              << DIE->getInit()->getSourceRange();
+          SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
+            << *Field;
+        }
+        Invalid = true;
+      }
+
+      // Check GNU flexible array initializer.
+      if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field,
+                                             TopLevelObject))
+        Invalid = true;
+
+      if (Invalid) {
+        ++Index;
+        return true;
+      }
+
+      // Initialize the array.
+      bool prevHadError = hadError;
+      unsigned newStructuredIndex = FieldIndex;
+      unsigned OldIndex = Index;
+      IList->setInit(Index, DIE->getInit());
+
+      InitializedEntity MemberEntity =
+        InitializedEntity::InitializeMember(*Field, &Entity);
+      CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
+                          StructuredList, newStructuredIndex);
+
+      IList->setInit(OldIndex, DIE);
+      if (hadError && !prevHadError) {
+        ++Field;
+        ++FieldIndex;
+        if (NextField)
+          *NextField = Field;
+        StructuredIndex = FieldIndex;
+        return true;
+      }
+    } else {
+      // Recurse to check later designated subobjects.
+      QualType FieldType = Field->getType();
+      unsigned newStructuredIndex = FieldIndex;
+
+      InitializedEntity MemberEntity =
+        InitializedEntity::InitializeMember(*Field, &Entity);
+      if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1,
+                                     FieldType, nullptr, nullptr, Index,
+                                     StructuredList, newStructuredIndex,
+                                     FinishSubobjectInit, false))
+        return true;
+    }
+
+    // Find the position of the next field to be initialized in this
+    // subobject.
+    ++Field;
+    ++FieldIndex;
+
+    // If this the first designator, our caller will continue checking
+    // the rest of this struct/class/union subobject.
+    if (IsFirstDesignator) {
+      if (NextField)
+        *NextField = Field;
+      StructuredIndex = FieldIndex;
+      return false;
+    }
+
+    if (!FinishSubobjectInit)
+      return false;
+
+    // We've already initialized something in the union; we're done.
+    if (RT->getDecl()->isUnion())
+      return hadError;
+
+    // Check the remaining fields within this class/struct/union subobject.
+    bool prevHadError = hadError;
+
+    auto NoBases =
+        CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
+                                        CXXRecordDecl::base_class_iterator());
+    CheckStructUnionTypes(Entity, IList, CurrentObjectType, NoBases, Field,
+                          false, Index, StructuredList, FieldIndex);
+    return hadError && !prevHadError;
+  }
+
+  // C99 6.7.8p6:
+  //
+  //   If a designator has the form
+  //
+  //      [ constant-expression ]
+  //
+  //   then the current object (defined below) shall have array
+  //   type and the expression shall be an integer constant
+  //   expression. If the array is of unknown size, any
+  //   nonnegative value is valid.
+  //
+  // Additionally, cope with the GNU extension that permits
+  // designators of the form
+  //
+  //      [ constant-expression ... constant-expression ]
+  const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType);
+  if (!AT) {
+    if (!VerifyOnly)
+      SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array)
+        << CurrentObjectType;
+    ++Index;
+    return true;
+  }
+
+  Expr *IndexExpr = nullptr;
+  llvm::APSInt DesignatedStartIndex, DesignatedEndIndex;
+  if (D->isArrayDesignator()) {
+    IndexExpr = DIE->getArrayIndex(*D);
+    DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context);
+    DesignatedEndIndex = DesignatedStartIndex;
+  } else {
+    assert(D->isArrayRangeDesignator() && "Need array-range designator");
+
+    DesignatedStartIndex =
+      DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context);
+    DesignatedEndIndex =
+      DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context);
+    IndexExpr = DIE->getArrayRangeEnd(*D);
+
+    // Codegen can't handle evaluating array range designators that have side
+    // effects, because we replicate the AST value for each initialized element.
+    // As such, set the sawArrayRangeDesignator() bit if we initialize multiple
+    // elements with something that has a side effect, so codegen can emit an
+    // "error unsupported" error instead of miscompiling the app.
+    if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&&
+        DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly)
+      FullyStructuredList->sawArrayRangeDesignator();
+  }
+
+  if (isa<ConstantArrayType>(AT)) {
+    llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false);
+    DesignatedStartIndex
+      = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth());
+    DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned());
+    DesignatedEndIndex
+      = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth());
+    DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned());
+    if (DesignatedEndIndex >= MaxElements) {
+      if (!VerifyOnly)
+        SemaRef.Diag(IndexExpr->getBeginLoc(),
+                     diag::err_array_designator_too_large)
+            << DesignatedEndIndex.toString(10) << MaxElements.toString(10)
+            << IndexExpr->getSourceRange();
+      ++Index;
+      return true;
+    }
+  } else {
+    unsigned DesignatedIndexBitWidth =
+      ConstantArrayType::getMaxSizeBits(SemaRef.Context);
+    DesignatedStartIndex =
+      DesignatedStartIndex.extOrTrunc(DesignatedIndexBitWidth);
+    DesignatedEndIndex =
+      DesignatedEndIndex.extOrTrunc(DesignatedIndexBitWidth);
+    DesignatedStartIndex.setIsUnsigned(true);
+    DesignatedEndIndex.setIsUnsigned(true);
+  }
+
+  if (!VerifyOnly && StructuredList->isStringLiteralInit()) {
+    // We're modifying a string literal init; we have to decompose the string
+    // so we can modify the individual characters.
+    ASTContext &Context = SemaRef.Context;
+    Expr *SubExpr = StructuredList->getInit(0)->IgnoreParens();
+
+    // Compute the character type
+    QualType CharTy = AT->getElementType();
+
+    // Compute the type of the integer literals.
+    QualType PromotedCharTy = CharTy;
+    if (CharTy->isPromotableIntegerType())
+      PromotedCharTy = Context.getPromotedIntegerType(CharTy);
+    unsigned PromotedCharTyWidth = Context.getTypeSize(PromotedCharTy);
+
+    if (StringLiteral *SL = dyn_cast<StringLiteral>(SubExpr)) {
+      // Get the length of the string.
+      uint64_t StrLen = SL->getLength();
+      if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
+        StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
+      StructuredList->resizeInits(Context, StrLen);
+
+      // Build a literal for each character in the string, and put them into
+      // the init list.
+      for (unsigned i = 0, e = StrLen; i != e; ++i) {
+        llvm::APInt CodeUnit(PromotedCharTyWidth, SL->getCodeUnit(i));
+        Expr *Init = new (Context) IntegerLiteral(
+            Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
+        if (CharTy != PromotedCharTy)
+          Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
+                                          Init, nullptr, VK_RValue);
+        StructuredList->updateInit(Context, i, Init);
+      }
+    } else {
+      ObjCEncodeExpr *E = cast<ObjCEncodeExpr>(SubExpr);
+      std::string Str;
+      Context.getObjCEncodingForType(E->getEncodedType(), Str);
+
+      // Get the length of the string.
+      uint64_t StrLen = Str.size();
+      if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
+        StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
+      StructuredList->resizeInits(Context, StrLen);
+
+      // Build a literal for each character in the string, and put them into
+      // the init list.
+      for (unsigned i = 0, e = StrLen; i != e; ++i) {
+        llvm::APInt CodeUnit(PromotedCharTyWidth, Str[i]);
+        Expr *Init = new (Context) IntegerLiteral(
+            Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
+        if (CharTy != PromotedCharTy)
+          Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
+                                          Init, nullptr, VK_RValue);
+        StructuredList->updateInit(Context, i, Init);
+      }
+    }
+  }
+
+  // Make sure that our non-designated initializer list has space
+  // for a subobject corresponding to this array element.
+  if (!VerifyOnly &&
+      DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits())
+    StructuredList->resizeInits(SemaRef.Context,
+                                DesignatedEndIndex.getZExtValue() + 1);
+
+  // Repeatedly perform subobject initializations in the range
+  // [DesignatedStartIndex, DesignatedEndIndex].
+
+  // Move to the next designator
+  unsigned ElementIndex = DesignatedStartIndex.getZExtValue();
+  unsigned OldIndex = Index;
+
+  InitializedEntity ElementEntity =
+    InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
+
+  while (DesignatedStartIndex <= DesignatedEndIndex) {
+    // Recurse to check later designated subobjects.
+    QualType ElementType = AT->getElementType();
+    Index = OldIndex;
+
+    ElementEntity.setElementIndex(ElementIndex);
+    if (CheckDesignatedInitializer(
+            ElementEntity, IList, DIE, DesigIdx + 1, ElementType, nullptr,
+            nullptr, Index, StructuredList, ElementIndex,
+            FinishSubobjectInit && (DesignatedStartIndex == DesignatedEndIndex),
+            false))
+      return true;
+
+    // Move to the next index in the array that we'll be initializing.
+    ++DesignatedStartIndex;
+    ElementIndex = DesignatedStartIndex.getZExtValue();
+  }
+
+  // If this the first designator, our caller will continue checking
+  // the rest of this array subobject.
+  if (IsFirstDesignator) {
+    if (NextElementIndex)
+      *NextElementIndex = DesignatedStartIndex;
+    StructuredIndex = ElementIndex;
+    return false;
+  }
+
+  if (!FinishSubobjectInit)
+    return false;
+
+  // Check the remaining elements within this array subobject.
+  bool prevHadError = hadError;
+  CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex,
+                 /*SubobjectIsDesignatorContext=*/false, Index,
+                 StructuredList, ElementIndex);
+  return hadError && !prevHadError;
+}
+
+// Get the structured initializer list for a subobject of type
+// @p CurrentObjectType.
+InitListExpr *
+InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
+                                            QualType CurrentObjectType,
+                                            InitListExpr *StructuredList,
+                                            unsigned StructuredIndex,
+                                            SourceRange InitRange,
+                                            bool IsFullyOverwritten) {
+  if (VerifyOnly)
+    return nullptr; // No structured list in verification-only mode.
+  Expr *ExistingInit = nullptr;
+  if (!StructuredList)
+    ExistingInit = SyntacticToSemantic.lookup(IList);
+  else if (StructuredIndex < StructuredList->getNumInits())
+    ExistingInit = StructuredList->getInit(StructuredIndex);
+
+  if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit))
+    // There might have already been initializers for subobjects of the current
+    // object, but a subsequent initializer list will overwrite the entirety
+    // of the current object. (See DR 253 and C99 6.7.8p21). e.g.,
+    //
+    // struct P { char x[6]; };
+    // struct P l = { .x[2] = 'x', .x = { [0] = 'f' } };
+    //
+    // The first designated initializer is ignored, and l.x is just "f".
+    if (!IsFullyOverwritten)
+      return Result;
+
+  if (ExistingInit) {
+    // We are creating an initializer list that initializes the
+    // subobjects of the current object, but there was already an
+    // initialization that completely initialized the current
+    // subobject, e.g., by a compound literal:
+    //
+    // struct X { int a, b; };
+    // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
+    //
+    // Here, xs[0].a == 0 and xs[0].b == 3, since the second,
+    // designated initializer re-initializes the whole
+    // subobject [0], overwriting previous initializers.
+    SemaRef.Diag(InitRange.getBegin(),
+                 diag::warn_subobject_initializer_overrides)
+      << InitRange;
+    SemaRef.Diag(ExistingInit->getBeginLoc(), diag::note_previous_initializer)
+        << /*FIXME:has side effects=*/0 << ExistingInit->getSourceRange();
+  }
+
+  InitListExpr *Result
+    = new (SemaRef.Context) InitListExpr(SemaRef.Context,
+                                         InitRange.getBegin(), None,
+                                         InitRange.getEnd());
+
+  QualType ResultType = CurrentObjectType;
+  if (!ResultType->isArrayType())
+    ResultType = ResultType.getNonLValueExprType(SemaRef.Context);
+  Result->setType(ResultType);
+
+  // Pre-allocate storage for the structured initializer list.
+  unsigned NumElements = 0;
+  unsigned NumInits = 0;
+  bool GotNumInits = false;
+  if (!StructuredList) {
+    NumInits = IList->getNumInits();
+    GotNumInits = true;
+  } else if (Index < IList->getNumInits()) {
+    if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) {
+      NumInits = SubList->getNumInits();
+      GotNumInits = true;
+    }
+  }
+
+  if (const ArrayType *AType
+      = SemaRef.Context.getAsArrayType(CurrentObjectType)) {
+    if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) {
+      NumElements = CAType->getSize().getZExtValue();
+      // Simple heuristic so that we don't allocate a very large
+      // initializer with many empty entries at the end.
+      if (GotNumInits && NumElements > NumInits)
+        NumElements = 0;
+    }
+  } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>())
+    NumElements = VType->getNumElements();
+  else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) {
+    RecordDecl *RDecl = RType->getDecl();
+    if (RDecl->isUnion())
+      NumElements = 1;
+    else
+      NumElements = std::distance(RDecl->field_begin(), RDecl->field_end());
+  }
+
+  Result->reserveInits(SemaRef.Context, NumElements);
+
+  // Link this new initializer list into the structured initializer
+  // lists.
+  if (StructuredList)
+    StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result);
+  else {
+    Result->setSyntacticForm(IList);
+    SyntacticToSemantic[IList] = Result;
+  }
+
+  return Result;
+}
+
+/// Update the initializer at index @p StructuredIndex within the
+/// structured initializer list to the value @p expr.
+void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList,
+                                                  unsigned &StructuredIndex,
+                                                  Expr *expr) {
+  // No structured initializer list to update
+  if (!StructuredList)
+    return;
+
+  if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context,
+                                                  StructuredIndex, expr)) {
+    // This initializer overwrites a previous initializer. Warn.
+    // We need to check on source range validity because the previous
+    // initializer does not have to be an explicit initializer.
+    // struct P { int a, b; };
+    // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
+    // There is an overwrite taking place because the first braced initializer
+    // list "{ .a = 2 }' already provides value for .p.b (which is zero).
+    if (PrevInit->getSourceRange().isValid()) {
+      SemaRef.Diag(expr->getBeginLoc(), diag::warn_initializer_overrides)
+          << expr->getSourceRange();
+
+      SemaRef.Diag(PrevInit->getBeginLoc(), diag::note_previous_initializer)
+          << /*FIXME:has side effects=*/0 << PrevInit->getSourceRange();
+    }
+  }
+
+  ++StructuredIndex;
+}
+
+/// Check that the given Index expression is a valid array designator
+/// value. This is essentially just a wrapper around
+/// VerifyIntegerConstantExpression that also checks for negative values
+/// and produces a reasonable diagnostic if there is a
+/// failure. Returns the index expression, possibly with an implicit cast
+/// added, on success.  If everything went okay, Value will receive the
+/// value of the constant expression.
+static ExprResult
+CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) {
+  SourceLocation Loc = Index->getBeginLoc();
+
+  // Make sure this is an integer constant expression.
+  ExprResult Result = S.VerifyIntegerConstantExpression(Index, &Value);
+  if (Result.isInvalid())
+    return Result;
+
+  if (Value.isSigned() && Value.isNegative())
+    return S.Diag(Loc, diag::err_array_designator_negative)
+      << Value.toString(10) << Index->getSourceRange();
+
+  Value.setIsUnsigned(true);
+  return Result;
+}
+
+ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig,
+                                            SourceLocation Loc,
+                                            bool GNUSyntax,
+                                            ExprResult Init) {
+  typedef DesignatedInitExpr::Designator ASTDesignator;
+
+  bool Invalid = false;
+  SmallVector<ASTDesignator, 32> Designators;
+  SmallVector<Expr *, 32> InitExpressions;
+
+  // Build designators and check array designator expressions.
+  for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) {
+    const Designator &D = Desig.getDesignator(Idx);
+    switch (D.getKind()) {
+    case Designator::FieldDesignator:
+      Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(),
+                                          D.getFieldLoc()));
+      break;
+
+    case Designator::ArrayDesignator: {
+      Expr *Index = static_cast<Expr *>(D.getArrayIndex());
+      llvm::APSInt IndexValue;
+      if (!Index->isTypeDependent() && !Index->isValueDependent())
+        Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).get();
+      if (!Index)
+        Invalid = true;
+      else {
+        Designators.push_back(ASTDesignator(InitExpressions.size(),
+                                            D.getLBracketLoc(),
+                                            D.getRBracketLoc()));
+        InitExpressions.push_back(Index);
+      }
+      break;
+    }
+
+    case Designator::ArrayRangeDesignator: {
+      Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart());
+      Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd());
+      llvm::APSInt StartValue;
+      llvm::APSInt EndValue;
+      bool StartDependent = StartIndex->isTypeDependent() ||
+                            StartIndex->isValueDependent();
+      bool EndDependent = EndIndex->isTypeDependent() ||
+                          EndIndex->isValueDependent();
+      if (!StartDependent)
+        StartIndex =
+            CheckArrayDesignatorExpr(*this, StartIndex, StartValue).get();
+      if (!EndDependent)
+        EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).get();
+
+      if (!StartIndex || !EndIndex)
+        Invalid = true;
+      else {
+        // Make sure we're comparing values with the same bit width.
+        if (StartDependent || EndDependent) {
+          // Nothing to compute.
+        } else if (StartValue.getBitWidth() > EndValue.getBitWidth())
+          EndValue = EndValue.extend(StartValue.getBitWidth());
+        else if (StartValue.getBitWidth() < EndValue.getBitWidth())
+          StartValue = StartValue.extend(EndValue.getBitWidth());
+
+        if (!StartDependent && !EndDependent && EndValue < StartValue) {
+          Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range)
+            << StartValue.toString(10) << EndValue.toString(10)
+            << StartIndex->getSourceRange() << EndIndex->getSourceRange();
+          Invalid = true;
+        } else {
+          Designators.push_back(ASTDesignator(InitExpressions.size(),
+                                              D.getLBracketLoc(),
+                                              D.getEllipsisLoc(),
+                                              D.getRBracketLoc()));
+          InitExpressions.push_back(StartIndex);
+          InitExpressions.push_back(EndIndex);
+        }
+      }
+      break;
+    }
+    }
+  }
+
+  if (Invalid || Init.isInvalid())
+    return ExprError();
+
+  // Clear out the expressions within the designation.
+  Desig.ClearExprs(*this);
+
+  DesignatedInitExpr *DIE
+    = DesignatedInitExpr::Create(Context,
+                                 Designators,
+                                 InitExpressions, Loc, GNUSyntax,
+                                 Init.getAs<Expr>());
+
+  if (!getLangOpts().C99)
+    Diag(DIE->getBeginLoc(), diag::ext_designated_init)
+        << DIE->getSourceRange();
+
+  return DIE;
+}
+
+//===----------------------------------------------------------------------===//
+// Initialization entity
+//===----------------------------------------------------------------------===//
+
+InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index,
+                                     const InitializedEntity &Parent)
+  : Parent(&Parent), Index(Index)
+{
+  if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) {
+    Kind = EK_ArrayElement;
+    Type = AT->getElementType();
+  } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) {
+    Kind = EK_VectorElement;
+    Type = VT->getElementType();
+  } else {
+    const ComplexType *CT = Parent.getType()->getAs<ComplexType>();
+    assert(CT && "Unexpected type");
+    Kind = EK_ComplexElement;
+    Type = CT->getElementType();
+  }
+}
+
+InitializedEntity
+InitializedEntity::InitializeBase(ASTContext &Context,
+                                  const CXXBaseSpecifier *Base,
+                                  bool IsInheritedVirtualBase,
+                                  const InitializedEntity *Parent) {
+  InitializedEntity Result;
+  Result.Kind = EK_Base;
+  Result.Parent = Parent;
+  Result.Base = reinterpret_cast<uintptr_t>(Base);
+  if (IsInheritedVirtualBase)
+    Result.Base |= 0x01;
+
+  Result.Type = Base->getType();
+  return Result;
+}
+
+DeclarationName InitializedEntity::getName() const {
+  switch (getKind()) {
+  case EK_Parameter:
+  case EK_Parameter_CF_Audited: {
+    ParmVarDecl *D = reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
+    return (D ? D->getDeclName() : DeclarationName());
+  }
+
+  case EK_Variable:
+  case EK_Member:
+  case EK_Binding:
+    return Variable.VariableOrMember->getDeclName();
+
+  case EK_LambdaCapture:
+    return DeclarationName(Capture.VarID);
+
+  case EK_Result:
+  case EK_StmtExprResult:
+  case EK_Exception:
+  case EK_New:
+  case EK_Temporary:
+  case EK_Base:
+  case EK_Delegating:
+  case EK_ArrayElement:
+  case EK_VectorElement:
+  case EK_ComplexElement:
+  case EK_BlockElement:
+  case EK_LambdaToBlockConversionBlockElement:
+  case EK_CompoundLiteralInit:
+  case EK_RelatedResult:
+    return DeclarationName();
+  }
+
+  llvm_unreachable("Invalid EntityKind!");
+}
+
+ValueDecl *InitializedEntity::getDecl() const {
+  switch (getKind()) {
+  case EK_Variable:
+  case EK_Member:
+  case EK_Binding:
+    return Variable.VariableOrMember;
+
+  case EK_Parameter:
+  case EK_Parameter_CF_Audited:
+    return reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
+
+  case EK_Result:
+  case EK_StmtExprResult:
+  case EK_Exception:
+  case EK_New:
+  case EK_Temporary:
+  case EK_Base:
+  case EK_Delegating:
+  case EK_ArrayElement:
+  case EK_VectorElement:
+  case EK_ComplexElement:
+  case EK_BlockElement:
+  case EK_LambdaToBlockConversionBlockElement:
+  case EK_LambdaCapture:
+  case EK_CompoundLiteralInit:
+  case EK_RelatedResult:
+    return nullptr;
+  }
+
+  llvm_unreachable("Invalid EntityKind!");
+}
+
+bool InitializedEntity::allowsNRVO() const {
+  switch (getKind()) {
+  case EK_Result:
+  case EK_Exception:
+    return LocAndNRVO.NRVO;
+
+  case EK_StmtExprResult:
+  case EK_Variable:
+  case EK_Parameter:
+  case EK_Parameter_CF_Audited:
+  case EK_Member:
+  case EK_Binding:
+  case EK_New:
+  case EK_Temporary:
+  case EK_CompoundLiteralInit:
+  case EK_Base:
+  case EK_Delegating:
+  case EK_ArrayElement:
+  case EK_VectorElement:
+  case EK_ComplexElement:
+  case EK_BlockElement:
+  case EK_LambdaToBlockConversionBlockElement:
+  case EK_LambdaCapture:
+  case EK_RelatedResult:
+    break;
+  }
+
+  return false;
+}
+
+unsigned InitializedEntity::dumpImpl(raw_ostream &OS) const {
+  assert(getParent() != this);
+  unsigned Depth = getParent() ? getParent()->dumpImpl(OS) : 0;
+  for (unsigned I = 0; I != Depth; ++I)
+    OS << "`-";
+
+  switch (getKind()) {
+  case EK_Variable: OS << "Variable"; break;
+  case EK_Parameter: OS << "Parameter"; break;
+  case EK_Parameter_CF_Audited: OS << "CF audited function Parameter";
+    break;
+  case EK_Result: OS << "Result"; break;
+  case EK_StmtExprResult: OS << "StmtExprResult"; break;
+  case EK_Exception: OS << "Exception"; break;
+  case EK_Member: OS << "Member"; break;
+  case EK_Binding: OS << "Binding"; break;
+  case EK_New: OS << "New"; break;
+  case EK_Temporary: OS << "Temporary"; break;
+  case EK_CompoundLiteralInit: OS << "CompoundLiteral";break;
+  case EK_RelatedResult: OS << "RelatedResult"; break;
+  case EK_Base: OS << "Base"; break;
+  case EK_Delegating: OS << "Delegating"; break;
+  case EK_ArrayElement: OS << "ArrayElement " << Index; break;
+  case EK_VectorElement: OS << "VectorElement " << Index; break;
+  case EK_ComplexElement: OS << "ComplexElement " << Index; break;
+  case EK_BlockElement: OS << "Block"; break;
+  case EK_LambdaToBlockConversionBlockElement:
+    OS << "Block (lambda)";
+    break;
+  case EK_LambdaCapture:
+    OS << "LambdaCapture ";
+    OS << DeclarationName(Capture.VarID);
+    break;
+  }
+
+  if (auto *D = getDecl()) {
+    OS << " ";
+    D->printQualifiedName(OS);
+  }
+
+  OS << " '" << getType().getAsString() << "'\n";
+
+  return Depth + 1;
+}
+
+LLVM_DUMP_METHOD void InitializedEntity::dump() const {
+  dumpImpl(llvm::errs());
+}
+
+//===----------------------------------------------------------------------===//
+// Initialization sequence
+//===----------------------------------------------------------------------===//
+
+void InitializationSequence::Step::Destroy() {
+  switch (Kind) {
+  case SK_ResolveAddressOfOverloadedFunction:
+  case SK_CastDerivedToBaseRValue:
+  case SK_CastDerivedToBaseXValue:
+  case SK_CastDerivedToBaseLValue:
+  case SK_BindReference:
+  case SK_BindReferenceToTemporary:
+  case SK_FinalCopy:
+  case SK_ExtraneousCopyToTemporary:
+  case SK_UserConversion:
+  case SK_QualificationConversionRValue:
+  case SK_QualificationConversionXValue:
+  case SK_QualificationConversionLValue:
+  case SK_AtomicConversion:
+  case SK_ListInitialization:
+  case SK_UnwrapInitList:
+  case SK_RewrapInitList:
+  case SK_ConstructorInitialization:
+  case SK_ConstructorInitializationFromList:
+  case SK_ZeroInitialization:
+  case SK_CAssignment:
+  case SK_StringInit:
+  case SK_ObjCObjectConversion:
+  case SK_ArrayLoopIndex:
+  case SK_ArrayLoopInit:
+  case SK_ArrayInit:
+  case SK_GNUArrayInit:
+  case SK_ParenthesizedArrayInit:
+  case SK_PassByIndirectCopyRestore:
+  case SK_PassByIndirectRestore:
+  case SK_ProduceObjCObject:
+  case SK_StdInitializerList:
+  case SK_StdInitializerListConstructorCall:
+  case SK_OCLSamplerInit:
+  case SK_OCLZeroOpaqueType:
+    break;
+
+  case SK_ConversionSequence:
+  case SK_ConversionSequenceNoNarrowing:
+    delete ICS;
+  }
+}
+
+bool InitializationSequence::isDirectReferenceBinding() const {
+  // There can be some lvalue adjustments after the SK_BindReference step.
+  for (auto I = Steps.rbegin(); I != Steps.rend(); ++I) {
+    if (I->Kind == SK_BindReference)
+      return true;
+    if (I->Kind == SK_BindReferenceToTemporary)
+      return false;
+  }
+  return false;
+}
+
+bool InitializationSequence::isAmbiguous() const {
+  if (!Failed())
+    return false;
+
+  switch (getFailureKind()) {
+  case FK_TooManyInitsForReference:
+  case FK_ParenthesizedListInitForReference:
+  case FK_ArrayNeedsInitList:
+  case FK_ArrayNeedsInitListOrStringLiteral:
+  case FK_ArrayNeedsInitListOrWideStringLiteral:
+  case FK_NarrowStringIntoWideCharArray:
+  case FK_WideStringIntoCharArray:
+  case FK_IncompatWideStringIntoWideChar:
+  case FK_PlainStringIntoUTF8Char:
+  case FK_UTF8StringIntoPlainChar:
+  case FK_AddressOfOverloadFailed: // FIXME: Could do better
+  case FK_NonConstLValueReferenceBindingToTemporary:
+  case FK_NonConstLValueReferenceBindingToBitfield:
+  case FK_NonConstLValueReferenceBindingToVectorElement:
+  case FK_NonConstLValueReferenceBindingToUnrelated:
+  case FK_RValueReferenceBindingToLValue:
+  case FK_ReferenceAddrspaceMismatchTemporary:
+  case FK_ReferenceInitDropsQualifiers:
+  case FK_ReferenceInitFailed:
+  case FK_ConversionFailed:
+  case FK_ConversionFromPropertyFailed:
+  case FK_TooManyInitsForScalar:
+  case FK_ParenthesizedListInitForScalar:
+  case FK_ReferenceBindingToInitList:
+  case FK_InitListBadDestinationType:
+  case FK_DefaultInitOfConst:
+  case FK_Incomplete:
+  case FK_ArrayTypeMismatch:
+  case FK_NonConstantArrayInit:
+  case FK_ListInitializationFailed:
+  case FK_VariableLengthArrayHasInitializer:
+  case FK_PlaceholderType:
+  case FK_ExplicitConstructor:
+  case FK_AddressOfUnaddressableFunction:
+    return false;
+
+  case FK_ReferenceInitOverloadFailed:
+  case FK_UserConversionOverloadFailed:
+  case FK_ConstructorOverloadFailed:
+  case FK_ListConstructorOverloadFailed:
+    return FailedOverloadResult == OR_Ambiguous;
+  }
+
+  llvm_unreachable("Invalid EntityKind!");
+}
+
+bool InitializationSequence::isConstructorInitialization() const {
+  return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization;
+}
+
+void
+InitializationSequence
+::AddAddressOverloadResolutionStep(FunctionDecl *Function,
+                                   DeclAccessPair Found,
+                                   bool HadMultipleCandidates) {
+  Step S;
+  S.Kind = SK_ResolveAddressOfOverloadedFunction;
+  S.Type = Function->getType();
+  S.Function.HadMultipleCandidates = HadMultipleCandidates;
+  S.Function.Function = Function;
+  S.Function.FoundDecl = Found;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType,
+                                                      ExprValueKind VK) {
+  Step S;
+  switch (VK) {
+  case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break;
+  case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break;
+  case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break;
+  }
+  S.Type = BaseType;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddReferenceBindingStep(QualType T,
+                                                     bool BindingTemporary) {
+  Step S;
+  S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddFinalCopy(QualType T) {
+  Step S;
+  S.Kind = SK_FinalCopy;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) {
+  Step S;
+  S.Kind = SK_ExtraneousCopyToTemporary;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void
+InitializationSequence::AddUserConversionStep(FunctionDecl *Function,
+                                              DeclAccessPair FoundDecl,
+                                              QualType T,
+                                              bool HadMultipleCandidates) {
+  Step S;
+  S.Kind = SK_UserConversion;
+  S.Type = T;
+  S.Function.HadMultipleCandidates = HadMultipleCandidates;
+  S.Function.Function = Function;
+  S.Function.FoundDecl = FoundDecl;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddQualificationConversionStep(QualType Ty,
+                                                            ExprValueKind VK) {
+  Step S;
+  S.Kind = SK_QualificationConversionRValue; // work around a gcc warning
+  switch (VK) {
+  case VK_RValue:
+    S.Kind = SK_QualificationConversionRValue;
+    break;
+  case VK_XValue:
+    S.Kind = SK_QualificationConversionXValue;
+    break;
+  case VK_LValue:
+    S.Kind = SK_QualificationConversionLValue;
+    break;
+  }
+  S.Type = Ty;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddAtomicConversionStep(QualType Ty) {
+  Step S;
+  S.Kind = SK_AtomicConversion;
+  S.Type = Ty;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddConversionSequenceStep(
+    const ImplicitConversionSequence &ICS, QualType T,
+    bool TopLevelOfInitList) {
+  Step S;
+  S.Kind = TopLevelOfInitList ? SK_ConversionSequenceNoNarrowing
+                              : SK_ConversionSequence;
+  S.Type = T;
+  S.ICS = new ImplicitConversionSequence(ICS);
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddListInitializationStep(QualType T) {
+  Step S;
+  S.Kind = SK_ListInitialization;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddConstructorInitializationStep(
+    DeclAccessPair FoundDecl, CXXConstructorDecl *Constructor, QualType T,
+    bool HadMultipleCandidates, bool FromInitList, bool AsInitList) {
+  Step S;
+  S.Kind = FromInitList ? AsInitList ? SK_StdInitializerListConstructorCall
+                                     : SK_ConstructorInitializationFromList
+                        : SK_ConstructorInitialization;
+  S.Type = T;
+  S.Function.HadMultipleCandidates = HadMultipleCandidates;
+  S.Function.Function = Constructor;
+  S.Function.FoundDecl = FoundDecl;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddZeroInitializationStep(QualType T) {
+  Step S;
+  S.Kind = SK_ZeroInitialization;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddCAssignmentStep(QualType T) {
+  Step S;
+  S.Kind = SK_CAssignment;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddStringInitStep(QualType T) {
+  Step S;
+  S.Kind = SK_StringInit;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddObjCObjectConversionStep(QualType T) {
+  Step S;
+  S.Kind = SK_ObjCObjectConversion;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddArrayInitStep(QualType T, bool IsGNUExtension) {
+  Step S;
+  S.Kind = IsGNUExtension ? SK_GNUArrayInit : SK_ArrayInit;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddArrayInitLoopStep(QualType T, QualType EltT) {
+  Step S;
+  S.Kind = SK_ArrayLoopIndex;
+  S.Type = EltT;
+  Steps.insert(Steps.begin(), S);
+
+  S.Kind = SK_ArrayLoopInit;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) {
+  Step S;
+  S.Kind = SK_ParenthesizedArrayInit;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type,
+                                                              bool shouldCopy) {
+  Step s;
+  s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore
+                       : SK_PassByIndirectRestore);
+  s.Type = type;
+  Steps.push_back(s);
+}
+
+void InitializationSequence::AddProduceObjCObjectStep(QualType T) {
+  Step S;
+  S.Kind = SK_ProduceObjCObject;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) {
+  Step S;
+  S.Kind = SK_StdInitializerList;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddOCLSamplerInitStep(QualType T) {
+  Step S;
+  S.Kind = SK_OCLSamplerInit;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::AddOCLZeroOpaqueTypeStep(QualType T) {
+  Step S;
+  S.Kind = SK_OCLZeroOpaqueType;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::RewrapReferenceInitList(QualType T,
+                                                     InitListExpr *Syntactic) {
+  assert(Syntactic->getNumInits() == 1 &&
+         "Can only rewrap trivial init lists.");
+  Step S;
+  S.Kind = SK_UnwrapInitList;
+  S.Type = Syntactic->getInit(0)->getType();
+  Steps.insert(Steps.begin(), S);
+
+  S.Kind = SK_RewrapInitList;
+  S.Type = T;
+  S.WrappingSyntacticList = Syntactic;
+  Steps.push_back(S);
+}
+
+void InitializationSequence::SetOverloadFailure(FailureKind Failure,
+                                                OverloadingResult Result) {
+  setSequenceKind(FailedSequence);
+  this->Failure = Failure;
+  this->FailedOverloadResult = Result;
+}
+
+//===----------------------------------------------------------------------===//
+// Attempt initialization
+//===----------------------------------------------------------------------===//
+
+/// Tries to add a zero initializer. Returns true if that worked.
+static bool
+maybeRecoverWithZeroInitialization(Sema &S, InitializationSequence &Sequence,
+                                   const InitializedEntity &Entity) {
+  if (Entity.getKind() != InitializedEntity::EK_Variable)
+    return false;
+
+  VarDecl *VD = cast<VarDecl>(Entity.getDecl());
+  if (VD->getInit() || VD->getEndLoc().isMacroID())
+    return false;
+
+  QualType VariableTy = VD->getType().getCanonicalType();
+  SourceLocation Loc = S.getLocForEndOfToken(VD->getEndLoc());
+  std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
+  if (!Init.empty()) {
+    Sequence.AddZeroInitializationStep(Entity.getType());
+    Sequence.SetZeroInitializationFixit(Init, Loc);
+    return true;
+  }
+  return false;
+}
+
+static void MaybeProduceObjCObject(Sema &S,
+                                   InitializationSequence &Sequence,
+                                   const InitializedEntity &Entity) {
+  if (!S.getLangOpts().ObjCAutoRefCount) return;
+
+  /// When initializing a parameter, produce the value if it's marked
+  /// __attribute__((ns_consumed)).
+  if (Entity.isParameterKind()) {
+    if (!Entity.isParameterConsumed())
+      return;
+
+    assert(Entity.getType()->isObjCRetainableType() &&
+           "consuming an object of unretainable type?");
+    Sequence.AddProduceObjCObjectStep(Entity.getType());
+
+  /// When initializing a return value, if the return type is a
+  /// retainable type, then returns need to immediately retain the
+  /// object.  If an autorelease is required, it will be done at the
+  /// last instant.
+  } else if (Entity.getKind() == InitializedEntity::EK_Result ||
+             Entity.getKind() == InitializedEntity::EK_StmtExprResult) {
+    if (!Entity.getType()->isObjCRetainableType())
+      return;
+
+    Sequence.AddProduceObjCObjectStep(Entity.getType());
+  }
+}
+
+static void TryListInitialization(Sema &S,
+                                  const InitializedEntity &Entity,
+                                  const InitializationKind &Kind,
+                                  InitListExpr *InitList,
+                                  InitializationSequence &Sequence,
+                                  bool TreatUnavailableAsInvalid);
+
+/// When initializing from init list via constructor, handle
+/// initialization of an object of type std::initializer_list<T>.
+///
+/// \return true if we have handled initialization of an object of type
+/// std::initializer_list<T>, false otherwise.
+static bool TryInitializerListConstruction(Sema &S,
+                                           InitListExpr *List,
+                                           QualType DestType,
+                                           InitializationSequence &Sequence,
+                                           bool TreatUnavailableAsInvalid) {
+  QualType E;
+  if (!S.isStdInitializerList(DestType, &E))
+    return false;
+
+  if (!S.isCompleteType(List->getExprLoc(), E)) {
+    Sequence.setIncompleteTypeFailure(E);
+    return true;
+  }
+
+  // Try initializing a temporary array from the init list.
+  QualType ArrayType = S.Context.getConstantArrayType(
+      E.withConst(), llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
+                                 List->getNumInits()),
+      clang::ArrayType::Normal, 0);
+  InitializedEntity HiddenArray =
+      InitializedEntity::InitializeTemporary(ArrayType);
+  InitializationKind Kind = InitializationKind::CreateDirectList(
+      List->getExprLoc(), List->getBeginLoc(), List->getEndLoc());
+  TryListInitialization(S, HiddenArray, Kind, List, Sequence,
+                        TreatUnavailableAsInvalid);
+  if (Sequence)
+    Sequence.AddStdInitializerListConstructionStep(DestType);
+  return true;
+}
+
+/// Determine if the constructor has the signature of a copy or move
+/// constructor for the type T of the class in which it was found. That is,
+/// determine if its first parameter is of type T or reference to (possibly
+/// cv-qualified) T.
+static bool hasCopyOrMoveCtorParam(ASTContext &Ctx,
+                                   const ConstructorInfo &Info) {
+  if (Info.Constructor->getNumParams() == 0)
+    return false;
+
+  QualType ParmT =
+      Info.Constructor->getParamDecl(0)->getType().getNonReferenceType();
+  QualType ClassT =
+      Ctx.getRecordType(cast<CXXRecordDecl>(Info.FoundDecl->getDeclContext()));
+
+  return Ctx.hasSameUnqualifiedType(ParmT, ClassT);
+}
+
+static OverloadingResult
+ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc,
+                           MultiExprArg Args,
+                           OverloadCandidateSet &CandidateSet,
+                           QualType DestType,
+                           DeclContext::lookup_result Ctors,
+                           OverloadCandidateSet::iterator &Best,
+                           bool CopyInitializing, bool AllowExplicit,
+                           bool OnlyListConstructors, bool IsListInit,
+                           bool SecondStepOfCopyInit = false) {
+  CandidateSet.clear(OverloadCandidateSet::CSK_InitByConstructor);
+  CandidateSet.setDestAS(DestType.getQualifiers().getAddressSpace());
+
+  for (NamedDecl *D : Ctors) {
+    auto Info = getConstructorInfo(D);
+    if (!Info.Constructor || Info.Constructor->isInvalidDecl())
+      continue;
+
+    if (!AllowExplicit && Info.Constructor->isExplicit())
+      continue;
+
+    if (OnlyListConstructors && !S.isInitListConstructor(Info.Constructor))
+      continue;
+
+    // C++11 [over.best.ics]p4:
+    //   ... and the constructor or user-defined conversion function is a
+    //   candidate by
+    //   - 13.3.1.3, when the argument is the temporary in the second step
+    //     of a class copy-initialization, or
+    //   - 13.3.1.4, 13.3.1.5, or 13.3.1.6 (in all cases), [not handled here]
+    //   - the second phase of 13.3.1.7 when the initializer list has exactly
+    //     one element that is itself an initializer list, and the target is
+    //     the first parameter of a constructor of class X, and the conversion
+    //     is to X or reference to (possibly cv-qualified X),
+    //   user-defined conversion sequences are not considered.
+    bool SuppressUserConversions =
+        SecondStepOfCopyInit ||
+        (IsListInit && Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
+         hasCopyOrMoveCtorParam(S.Context, Info));
+
+    if (Info.ConstructorTmpl)
+      S.AddTemplateOverloadCandidate(
+          Info.ConstructorTmpl, Info.FoundDecl,
+          /*ExplicitArgs*/ nullptr, Args, CandidateSet, SuppressUserConversions,
+          /*PartialOverloading=*/false, AllowExplicit);
+    else {
+      // C++ [over.match.copy]p1:
+      //   - When initializing a temporary to be bound to the first parameter
+      //     of a constructor [for type T] that takes a reference to possibly
+      //     cv-qualified T as its first argument, called with a single
+      //     argument in the context of direct-initialization, explicit
+      //     conversion functions are also considered.
+      // FIXME: What if a constructor template instantiates to such a signature?
+      bool AllowExplicitConv = AllowExplicit && !CopyInitializing &&
+                               Args.size() == 1 &&
+                               hasCopyOrMoveCtorParam(S.Context, Info);
+      S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl, Args,
+                             CandidateSet, SuppressUserConversions,
+                             /*PartialOverloading=*/false, AllowExplicit,
+                             AllowExplicitConv);
+    }
+  }
+
+  // FIXME: Work around a bug in C++17 guaranteed copy elision.
+  //
+  // When initializing an object of class type T by constructor
+  // ([over.match.ctor]) or by list-initialization ([over.match.list])
+  // from a single expression of class type U, conversion functions of
+  // U that convert to the non-reference type cv T are candidates.
+  // Explicit conversion functions are only candidates during
+  // direct-initialization.
+  //
+  // Note: SecondStepOfCopyInit is only ever true in this case when
+  // evaluating whether to produce a C++98 compatibility warning.
+  if (S.getLangOpts().CPlusPlus17 && Args.size() == 1 &&
+      !SecondStepOfCopyInit) {
+    Expr *Initializer = Args[0];
+    auto *SourceRD = Initializer->getType()->getAsCXXRecordDecl();
+    if (SourceRD && S.isCompleteType(DeclLoc, Initializer->getType())) {
+      const auto &Conversions = SourceRD->getVisibleConversionFunctions();
+      for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
+        NamedDecl *D = *I;
+        CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
+        D = D->getUnderlyingDecl();
+
+        FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
+        CXXConversionDecl *Conv;
+        if (ConvTemplate)
+          Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
+        else
+          Conv = cast<CXXConversionDecl>(D);
+
+        if (AllowExplicit || !Conv->isExplicit()) {
+          if (ConvTemplate)
+            S.AddTemplateConversionCandidate(
+                ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
+                CandidateSet, AllowExplicit, AllowExplicit,
+                /*AllowResultConversion*/ false);
+          else
+            S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Initializer,
+                                     DestType, CandidateSet, AllowExplicit,
+                                     AllowExplicit,
+                                     /*AllowResultConversion*/ false);
+        }
+      }
+    }
+  }
+
+  // Perform overload resolution and return the result.
+  return CandidateSet.BestViableFunction(S, DeclLoc, Best);
+}
+
+/// Attempt initialization by constructor (C++ [dcl.init]), which
+/// enumerates the constructors of the initialized entity and performs overload
+/// resolution to select the best.
+/// \param DestType       The destination class type.
+/// \param DestArrayType  The destination type, which is either DestType or
+///                       a (possibly multidimensional) array of DestType.
+/// \param IsListInit     Is this list-initialization?
+/// \param IsInitListCopy Is this non-list-initialization resulting from a
+///                       list-initialization from {x} where x is the same
+///                       type as the entity?
+static void TryConstructorInitialization(Sema &S,
+                                         const InitializedEntity &Entity,
+                                         const InitializationKind &Kind,
+                                         MultiExprArg Args, QualType DestType,
+                                         QualType DestArrayType,
+                                         InitializationSequence &Sequence,
+                                         bool IsListInit = false,
+                                         bool IsInitListCopy = false) {
+  assert(((!IsListInit && !IsInitListCopy) ||
+          (Args.size() == 1 && isa<InitListExpr>(Args[0]))) &&
+         "IsListInit/IsInitListCopy must come with a single initializer list "
+         "argument.");
+  InitListExpr *ILE =
+      (IsListInit || IsInitListCopy) ? cast<InitListExpr>(Args[0]) : nullptr;
+  MultiExprArg UnwrappedArgs =
+      ILE ? MultiExprArg(ILE->getInits(), ILE->getNumInits()) : Args;
+
+  // The type we're constructing needs to be complete.
+  if (!S.isCompleteType(Kind.getLocation(), DestType)) {
+    Sequence.setIncompleteTypeFailure(DestType);
+    return;
+  }
+
+  // C++17 [dcl.init]p17:
+  //     - If the initializer expression is a prvalue and the cv-unqualified
+  //       version of the source type is the same class as the class of the
+  //       destination, the initializer expression is used to initialize the
+  //       destination object.
+  // Per DR (no number yet), this does not apply when initializing a base
+  // class or delegating to another constructor from a mem-initializer.
+  // ObjC++: Lambda captured by the block in the lambda to block conversion
+  // should avoid copy elision.
+  if (S.getLangOpts().CPlusPlus17 &&
+      Entity.getKind() != InitializedEntity::EK_Base &&
+      Entity.getKind() != InitializedEntity::EK_Delegating &&
+      Entity.getKind() !=
+          InitializedEntity::EK_LambdaToBlockConversionBlockElement &&
+      UnwrappedArgs.size() == 1 && UnwrappedArgs[0]->isRValue() &&
+      S.Context.hasSameUnqualifiedType(UnwrappedArgs[0]->getType(), DestType)) {
+    // Convert qualifications if necessary.
+    Sequence.AddQualificationConversionStep(DestType, VK_RValue);
+    if (ILE)
+      Sequence.RewrapReferenceInitList(DestType, ILE);
+    return;
+  }
+
+  const RecordType *DestRecordType = DestType->getAs<RecordType>();
+  assert(DestRecordType && "Constructor initialization requires record type");
+  CXXRecordDecl *DestRecordDecl
+    = cast<CXXRecordDecl>(DestRecordType->getDecl());
+
+  // Build the candidate set directly in the initialization sequence
+  // structure, so that it will persist if we fail.
+  OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
+
+  // Determine whether we are allowed to call explicit constructors or
+  // explicit conversion operators.
+  bool AllowExplicit = Kind.AllowExplicit() || IsListInit;
+  bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy;
+
+  //   - Otherwise, if T is a class type, constructors are considered. The
+  //     applicable constructors are enumerated, and the best one is chosen
+  //     through overload resolution.
+  DeclContext::lookup_result Ctors = S.LookupConstructors(DestRecordDecl);
+
+  OverloadingResult Result = OR_No_Viable_Function;
+  OverloadCandidateSet::iterator Best;
+  bool AsInitializerList = false;
+
+  // C++11 [over.match.list]p1, per DR1467:
+  //   When objects of non-aggregate type T are list-initialized, such that
+  //   8.5.4 [dcl.init.list] specifies that overload resolution is performed
+  //   according to the rules in this section, overload resolution selects
+  //   the constructor in two phases:
+  //
+  //   - Initially, the candidate functions are the initializer-list
+  //     constructors of the class T and the argument list consists of the
+  //     initializer list as a single argument.
+  if (IsListInit) {
+    AsInitializerList = true;
+
+    // If the initializer list has no elements and T has a default constructor,
+    // the first phase is omitted.
+    if (!(UnwrappedArgs.empty() && DestRecordDecl->hasDefaultConstructor()))
+      Result = ResolveConstructorOverload(S, Kind.getLocation(), Args,
+                                          CandidateSet, DestType, Ctors, Best,
+                                          CopyInitialization, AllowExplicit,
+                                          /*OnlyListConstructors=*/true,
+                                          IsListInit);
+  }
+
+  // C++11 [over.match.list]p1:
+  //   - If no viable initializer-list constructor is found, overload resolution
+  //     is performed again, where the candidate functions are all the
+  //     constructors of the class T and the argument list consists of the
+  //     elements of the initializer list.
+  if (Result == OR_No_Viable_Function) {
+    AsInitializerList = false;
+    Result = ResolveConstructorOverload(S, Kind.getLocation(), UnwrappedArgs,
+                                        CandidateSet, DestType, Ctors, Best,
+                                        CopyInitialization, AllowExplicit,
+                                        /*OnlyListConstructors=*/false,
+                                        IsListInit);
+  }
+  if (Result) {
+    Sequence.SetOverloadFailure(IsListInit ?
+                      InitializationSequence::FK_ListConstructorOverloadFailed :
+                      InitializationSequence::FK_ConstructorOverloadFailed,
+                                Result);
+    return;
+  }
+
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
+  // In C++17, ResolveConstructorOverload can select a conversion function
+  // instead of a constructor.
+  if (auto *CD = dyn_cast<CXXConversionDecl>(Best->Function)) {
+    // Add the user-defined conversion step that calls the conversion function.
+    QualType ConvType = CD->getConversionType();
+    assert(S.Context.hasSameUnqualifiedType(ConvType, DestType) &&
+           "should not have selected this conversion function");
+    Sequence.AddUserConversionStep(CD, Best->FoundDecl, ConvType,
+                                   HadMultipleCandidates);
+    if (!S.Context.hasSameType(ConvType, DestType))
+      Sequence.AddQualificationConversionStep(DestType, VK_RValue);
+    if (IsListInit)
+      Sequence.RewrapReferenceInitList(Entity.getType(), ILE);
+    return;
+  }
+
+  // C++11 [dcl.init]p6:
+  //   If a program calls for the default initialization of an object
+  //   of a const-qualified type T, T shall be a class type with a
+  //   user-provided default constructor.
+  // C++ core issue 253 proposal:
+  //   If the implicit default constructor initializes all subobjects, no
+  //   initializer should be required.
+  // The 253 proposal is for example needed to process libstdc++ headers in 5.x.
+  CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
+  if (Kind.getKind() == InitializationKind::IK_Default &&
+      Entity.getType().isConstQualified()) {
+    if (!CtorDecl->getParent()->allowConstDefaultInit()) {
+      if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
+        Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
+      return;
+    }
+  }
+
+  // C++11 [over.match.list]p1:
+  //   In copy-list-initialization, if an explicit constructor is chosen, the
+  //   initializer is ill-formed.
+  if (IsListInit && !Kind.AllowExplicit() && CtorDecl->isExplicit()) {
+    Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor);
+    return;
+  }
+
+  // Add the constructor initialization step. Any cv-qualification conversion is
+  // subsumed by the initialization.
+  Sequence.AddConstructorInitializationStep(
+      Best->FoundDecl, CtorDecl, DestArrayType, HadMultipleCandidates,
+      IsListInit | IsInitListCopy, AsInitializerList);
+}
+
+static bool
+ResolveOverloadedFunctionForReferenceBinding(Sema &S,
+                                             Expr *Initializer,
+                                             QualType &SourceType,
+                                             QualType &UnqualifiedSourceType,
+                                             QualType UnqualifiedTargetType,
+                                             InitializationSequence &Sequence) {
+  if (S.Context.getCanonicalType(UnqualifiedSourceType) ==
+        S.Context.OverloadTy) {
+    DeclAccessPair Found;
+    bool HadMultipleCandidates = false;
+    if (FunctionDecl *Fn
+        = S.ResolveAddressOfOverloadedFunction(Initializer,
+                                               UnqualifiedTargetType,
+                                               false, Found,
+                                               &HadMultipleCandidates)) {
+      Sequence.AddAddressOverloadResolutionStep(Fn, Found,
+                                                HadMultipleCandidates);
+      SourceType = Fn->getType();
+      UnqualifiedSourceType = SourceType.getUnqualifiedType();
+    } else if (!UnqualifiedTargetType->isRecordType()) {
+      Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
+      return true;
+    }
+  }
+  return false;
+}
+
+static void TryReferenceInitializationCore(Sema &S,
+                                           const InitializedEntity &Entity,
+                                           const InitializationKind &Kind,
+                                           Expr *Initializer,
+                                           QualType cv1T1, QualType T1,
+                                           Qualifiers T1Quals,
+                                           QualType cv2T2, QualType T2,
+                                           Qualifiers T2Quals,
+                                           InitializationSequence &Sequence);
+
+static void TryValueInitialization(Sema &S,
+                                   const InitializedEntity &Entity,
+                                   const InitializationKind &Kind,
+                                   InitializationSequence &Sequence,
+                                   InitListExpr *InitList = nullptr);
+
+/// Attempt list initialization of a reference.
+static void TryReferenceListInitialization(Sema &S,
+                                           const InitializedEntity &Entity,
+                                           const InitializationKind &Kind,
+                                           InitListExpr *InitList,
+                                           InitializationSequence &Sequence,
+                                           bool TreatUnavailableAsInvalid) {
+  // First, catch C++03 where this isn't possible.
+  if (!S.getLangOpts().CPlusPlus11) {
+    Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
+    return;
+  }
+  // Can't reference initialize a compound literal.
+  if (Entity.getKind() == InitializedEntity::EK_CompoundLiteralInit) {
+    Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
+    return;
+  }
+
+  QualType DestType = Entity.getType();
+  QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
+  Qualifiers T1Quals;
+  QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
+
+  // Reference initialization via an initializer list works thus:
+  // If the initializer list consists of a single element that is
+  // reference-related to the referenced type, bind directly to that element
+  // (possibly creating temporaries).
+  // Otherwise, initialize a temporary with the initializer list and
+  // bind to that.
+  if (InitList->getNumInits() == 1) {
+    Expr *Initializer = InitList->getInit(0);
+    QualType cv2T2 = Initializer->getType();
+    Qualifiers T2Quals;
+    QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
+
+    // If this fails, creating a temporary wouldn't work either.
+    if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
+                                                     T1, Sequence))
+      return;
+
+    SourceLocation DeclLoc = Initializer->getBeginLoc();
+    bool dummy1, dummy2, dummy3;
+    Sema::ReferenceCompareResult RefRelationship
+      = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, dummy1,
+                                       dummy2, dummy3);
+    if (RefRelationship >= Sema::Ref_Related) {
+      // Try to bind the reference here.
+      TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
+                                     T1Quals, cv2T2, T2, T2Quals, Sequence);
+      if (Sequence)
+        Sequence.RewrapReferenceInitList(cv1T1, InitList);
+      return;
+    }
+
+    // Update the initializer if we've resolved an overloaded function.
+    if (Sequence.step_begin() != Sequence.step_end())
+      Sequence.RewrapReferenceInitList(cv1T1, InitList);
+  }
+
+  // Not reference-related. Create a temporary and bind to that.
+  InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
+
+  TryListInitialization(S, TempEntity, Kind, InitList, Sequence,
+                        TreatUnavailableAsInvalid);
+  if (Sequence) {
+    if (DestType->isRValueReferenceType() ||
+        (T1Quals.hasConst() && !T1Quals.hasVolatile()))
+      Sequence.AddReferenceBindingStep(cv1T1, /*BindingTemporary=*/true);
+    else
+      Sequence.SetFailed(
+          InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
+  }
+}
+
+/// Attempt list initialization (C++0x [dcl.init.list])
+static void TryListInitialization(Sema &S,
+                                  const InitializedEntity &Entity,
+                                  const InitializationKind &Kind,
+                                  InitListExpr *InitList,
+                                  InitializationSequence &Sequence,
+                                  bool TreatUnavailableAsInvalid) {
+  QualType DestType = Entity.getType();
+
+  // C++ doesn't allow scalar initialization with more than one argument.
+  // But C99 complex numbers are scalars and it makes sense there.
+  if (S.getLangOpts().CPlusPlus && DestType->isScalarType() &&
+      !DestType->isAnyComplexType() && InitList->getNumInits() > 1) {
+    Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar);
+    return;
+  }
+  if (DestType->isReferenceType()) {
+    TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence,
+                                   TreatUnavailableAsInvalid);
+    return;
+  }
+
+  if (DestType->isRecordType() &&
+      !S.isCompleteType(InitList->getBeginLoc(), DestType)) {
+    Sequence.setIncompleteTypeFailure(DestType);
+    return;
+  }
+
+  // C++11 [dcl.init.list]p3, per DR1467:
+  // - If T is a class type and the initializer list has a single element of
+  //   type cv U, where U is T or a class derived from T, the object is
+  //   initialized from that element (by copy-initialization for
+  //   copy-list-initialization, or by direct-initialization for
+  //   direct-list-initialization).
+  // - Otherwise, if T is a character array and the initializer list has a
+  //   single element that is an appropriately-typed string literal
+  //   (8.5.2 [dcl.init.string]), initialization is performed as described
+  //   in that section.
+  // - Otherwise, if T is an aggregate, [...] (continue below).
+  if (S.getLangOpts().CPlusPlus11 && InitList->getNumInits() == 1) {
+    if (DestType->isRecordType()) {
+      QualType InitType = InitList->getInit(0)->getType();
+      if (S.Context.hasSameUnqualifiedType(InitType, DestType) ||
+          S.IsDerivedFrom(InitList->getBeginLoc(), InitType, DestType)) {
+        Expr *InitListAsExpr = InitList;
+        TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
+                                     DestType, Sequence,
+                                     /*InitListSyntax*/false,
+                                     /*IsInitListCopy*/true);
+        return;
+      }
+    }
+    if (const ArrayType *DestAT = S.Context.getAsArrayType(DestType)) {
+      Expr *SubInit[1] = {InitList->getInit(0)};
+      if (!isa<VariableArrayType>(DestAT) &&
+          IsStringInit(SubInit[0], DestAT, S.Context) == SIF_None) {
+        InitializationKind SubKind =
+            Kind.getKind() == InitializationKind::IK_DirectList
+                ? InitializationKind::CreateDirect(Kind.getLocation(),
+                                                   InitList->getLBraceLoc(),
+                                                   InitList->getRBraceLoc())
+                : Kind;
+        Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
+                                /*TopLevelOfInitList*/ true,
+                                TreatUnavailableAsInvalid);
+
+        // TryStringLiteralInitialization() (in InitializeFrom()) will fail if
+        // the element is not an appropriately-typed string literal, in which
+        // case we should proceed as in C++11 (below).
+        if (Sequence) {
+          Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
+          return;
+        }
+      }
+    }
+  }
+
+  // C++11 [dcl.init.list]p3:
+  //   - If T is an aggregate, aggregate initialization is performed.
+  if ((DestType->isRecordType() && !DestType->isAggregateType()) ||
+      (S.getLangOpts().CPlusPlus11 &&
+       S.isStdInitializerList(DestType, nullptr))) {
+    if (S.getLangOpts().CPlusPlus11) {
+      //   - Otherwise, if the initializer list has no elements and T is a
+      //     class type with a default constructor, the object is
+      //     value-initialized.
+      if (InitList->getNumInits() == 0) {
+        CXXRecordDecl *RD = DestType->getAsCXXRecordDecl();
+        if (RD->hasDefaultConstructor()) {
+          TryValueInitialization(S, Entity, Kind, Sequence, InitList);
+          return;
+        }
+      }
+
+      //   - Otherwise, if T is a specialization of std::initializer_list<E>,
+      //     an initializer_list object constructed [...]
+      if (TryInitializerListConstruction(S, InitList, DestType, Sequence,
+                                         TreatUnavailableAsInvalid))
+        return;
+
+      //   - Otherwise, if T is a class type, constructors are considered.
+      Expr *InitListAsExpr = InitList;
+      TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
+                                   DestType, Sequence, /*InitListSyntax*/true);
+    } else
+      Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType);
+    return;
+  }
+
+  if (S.getLangOpts().CPlusPlus && !DestType->isAggregateType() &&
+      InitList->getNumInits() == 1) {
+    Expr *E = InitList->getInit(0);
+
+    //   - Otherwise, if T is an enumeration with a fixed underlying type,
+    //     the initializer-list has a single element v, and the initialization
+    //     is direct-list-initialization, the object is initialized with the
+    //     value T(v); if a narrowing conversion is required to convert v to
+    //     the underlying type of T, the program is ill-formed.
+    auto *ET = DestType->getAs<EnumType>();
+    if (S.getLangOpts().CPlusPlus17 &&
+        Kind.getKind() == InitializationKind::IK_DirectList &&
+        ET && ET->getDecl()->isFixed() &&
+        !S.Context.hasSameUnqualifiedType(E->getType(), DestType) &&
+        (E->getType()->isIntegralOrEnumerationType() ||
+         E->getType()->isFloatingType())) {
+      // There are two ways that T(v) can work when T is an enumeration type.
+      // If there is either an implicit conversion sequence from v to T or
+      // a conversion function that can convert from v to T, then we use that.
+      // Otherwise, if v is of integral, enumeration, or floating-point type,
+      // it is converted to the enumeration type via its underlying type.
+      // There is no overlap possible between these two cases (except when the
+      // source value is already of the destination type), and the first
+      // case is handled by the general case for single-element lists below.
+      ImplicitConversionSequence ICS;
+      ICS.setStandard();
+      ICS.Standard.setAsIdentityConversion();
+      if (!E->isRValue())
+        ICS.Standard.First = ICK_Lvalue_To_Rvalue;
+      // If E is of a floating-point type, then the conversion is ill-formed
+      // due to narrowing, but go through the motions in order to produce the
+      // right diagnostic.
+      ICS.Standard.Second = E->getType()->isFloatingType()
+                                ? ICK_Floating_Integral
+                                : ICK_Integral_Conversion;
+      ICS.Standard.setFromType(E->getType());
+      ICS.Standard.setToType(0, E->getType());
+      ICS.Standard.setToType(1, DestType);
+      ICS.Standard.setToType(2, DestType);
+      Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2),
+                                         /*TopLevelOfInitList*/true);
+      Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
+      return;
+    }
+
+    //   - Otherwise, if the initializer list has a single element of type E
+    //     [...references are handled above...], the object or reference is
+    //     initialized from that element (by copy-initialization for
+    //     copy-list-initialization, or by direct-initialization for
+    //     direct-list-initialization); if a narrowing conversion is required
+    //     to convert the element to T, the program is ill-formed.
+    //
+    // Per core-24034, this is direct-initialization if we were performing
+    // direct-list-initialization and copy-initialization otherwise.
+    // We can't use InitListChecker for this, because it always performs
+    // copy-initialization. This only matters if we might use an 'explicit'
+    // conversion operator, so we only need to handle the cases where the source
+    // is of record type.
+    if (InitList->getInit(0)->getType()->isRecordType()) {
+      InitializationKind SubKind =
+          Kind.getKind() == InitializationKind::IK_DirectList
+              ? InitializationKind::CreateDirect(Kind.getLocation(),
+                                                 InitList->getLBraceLoc(),
+                                                 InitList->getRBraceLoc())
+              : Kind;
+      Expr *SubInit[1] = { InitList->getInit(0) };
+      Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
+                              /*TopLevelOfInitList*/true,
+                              TreatUnavailableAsInvalid);
+      if (Sequence)
+        Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
+      return;
+    }
+  }
+
+  InitListChecker CheckInitList(S, Entity, InitList,
+          DestType, /*VerifyOnly=*/true, TreatUnavailableAsInvalid);
+  if (CheckInitList.HadError()) {
+    Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed);
+    return;
+  }
+
+  // Add the list initialization step with the built init list.
+  Sequence.AddListInitializationStep(DestType);
+}
+
+/// Try a reference initialization that involves calling a conversion
+/// function.
+static OverloadingResult TryRefInitWithConversionFunction(
+    Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind,
+    Expr *Initializer, bool AllowRValues, bool IsLValueRef,
+    InitializationSequence &Sequence) {
+  QualType DestType = Entity.getType();
+  QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
+  QualType T1 = cv1T1.getUnqualifiedType();
+  QualType cv2T2 = Initializer->getType();
+  QualType T2 = cv2T2.getUnqualifiedType();
+
+  bool DerivedToBase;
+  bool ObjCConversion;
+  bool ObjCLifetimeConversion;
+  assert(!S.CompareReferenceRelationship(Initializer->getBeginLoc(), T1, T2,
+                                         DerivedToBase, ObjCConversion,
+                                         ObjCLifetimeConversion) &&
+         "Must have incompatible references when binding via conversion");
+  (void)DerivedToBase;
+  (void)ObjCConversion;
+  (void)ObjCLifetimeConversion;
+
+  // Build the candidate set directly in the initialization sequence
+  // structure, so that it will persist if we fail.
+  OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
+  CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
+
+  // Determine whether we are allowed to call explicit conversion operators.
+  // Note that none of [over.match.copy], [over.match.conv], nor
+  // [over.match.ref] permit an explicit constructor to be chosen when
+  // initializing a reference, not even for direct-initialization.
+  bool AllowExplicitCtors = false;
+  bool AllowExplicitConvs = Kind.allowExplicitConversionFunctionsInRefBinding();
+
+  const RecordType *T1RecordType = nullptr;
+  if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) &&
+      S.isCompleteType(Kind.getLocation(), T1)) {
+    // The type we're converting to is a class type. Enumerate its constructors
+    // to see if there is a suitable conversion.
+    CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl());
+
+    for (NamedDecl *D : S.LookupConstructors(T1RecordDecl)) {
+      auto Info = getConstructorInfo(D);
+      if (!Info.Constructor)
+        continue;
+
+      if (!Info.Constructor->isInvalidDecl() &&
+          Info.Constructor->isConvertingConstructor(AllowExplicitCtors)) {
+        if (Info.ConstructorTmpl)
+          S.AddTemplateOverloadCandidate(
+              Info.ConstructorTmpl, Info.FoundDecl,
+              /*ExplicitArgs*/ nullptr, Initializer, CandidateSet,
+              /*SuppressUserConversions=*/true,
+              /*PartialOverloading*/ false, AllowExplicitCtors);
+        else
+          S.AddOverloadCandidate(
+              Info.Constructor, Info.FoundDecl, Initializer, CandidateSet,
+              /*SuppressUserConversions=*/true,
+              /*PartialOverloading*/ false, AllowExplicitCtors);
+      }
+    }
+  }
+  if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl())
+    return OR_No_Viable_Function;
+
+  const RecordType *T2RecordType = nullptr;
+  if ((T2RecordType = T2->getAs<RecordType>()) &&
+      S.isCompleteType(Kind.getLocation(), T2)) {
+    // The type we're converting from is a class type, enumerate its conversion
+    // functions.
+    CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl());
+
+    const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
+    for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
+      NamedDecl *D = *I;
+      CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
+      if (isa<UsingShadowDecl>(D))
+        D = cast<UsingShadowDecl>(D)->getTargetDecl();
+
+      FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
+      CXXConversionDecl *Conv;
+      if (ConvTemplate)
+        Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
+      else
+        Conv = cast<CXXConversionDecl>(D);
+
+      // If the conversion function doesn't return a reference type,
+      // it can't be considered for this conversion unless we're allowed to
+      // consider rvalues.
+      // FIXME: Do we need to make sure that we only consider conversion
+      // candidates with reference-compatible results? That might be needed to
+      // break recursion.
+      if ((AllowExplicitConvs || !Conv->isExplicit()) &&
+          (AllowRValues ||
+           Conv->getConversionType()->isLValueReferenceType())) {
+        if (ConvTemplate)
+          S.AddTemplateConversionCandidate(
+              ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
+              CandidateSet,
+              /*AllowObjCConversionOnExplicit=*/false, AllowExplicitConvs);
+        else
+          S.AddConversionCandidate(
+              Conv, I.getPair(), ActingDC, Initializer, DestType, CandidateSet,
+              /*AllowObjCConversionOnExplicit=*/false, AllowExplicitConvs);
+      }
+    }
+  }
+  if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl())
+    return OR_No_Viable_Function;
+
+  SourceLocation DeclLoc = Initializer->getBeginLoc();
+
+  // Perform overload resolution. If it fails, return the failed result.
+  OverloadCandidateSet::iterator Best;
+  if (OverloadingResult Result
+        = CandidateSet.BestViableFunction(S, DeclLoc, Best))
+    return Result;
+
+  FunctionDecl *Function = Best->Function;
+  // This is the overload that will be used for this initialization step if we
+  // use this initialization. Mark it as referenced.
+  Function->setReferenced();
+
+  // Compute the returned type and value kind of the conversion.
+  QualType cv3T3;
+  if (isa<CXXConversionDecl>(Function))
+    cv3T3 = Function->getReturnType();
+  else
+    cv3T3 = T1;
+
+  ExprValueKind VK = VK_RValue;
+  if (cv3T3->isLValueReferenceType())
+    VK = VK_LValue;
+  else if (const auto *RRef = cv3T3->getAs<RValueReferenceType>())
+    VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue;
+  cv3T3 = cv3T3.getNonLValueExprType(S.Context);
+
+  // Add the user-defined conversion step.
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+  Sequence.AddUserConversionStep(Function, Best->FoundDecl, cv3T3,
+                                 HadMultipleCandidates);
+
+  // Determine whether we'll need to perform derived-to-base adjustments or
+  // other conversions.
+  bool NewDerivedToBase = false;
+  bool NewObjCConversion = false;
+  bool NewObjCLifetimeConversion = false;
+  Sema::ReferenceCompareResult NewRefRelationship
+    = S.CompareReferenceRelationship(DeclLoc, T1, cv3T3,
+                                     NewDerivedToBase, NewObjCConversion,
+                                     NewObjCLifetimeConversion);
+
+  // Add the final conversion sequence, if necessary.
+  if (NewRefRelationship == Sema::Ref_Incompatible) {
+    assert(!isa<CXXConstructorDecl>(Function) &&
+           "should not have conversion after constructor");
+
+    ImplicitConversionSequence ICS;
+    ICS.setStandard();
+    ICS.Standard = Best->FinalConversion;
+    Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2));
+
+    // Every implicit conversion results in a prvalue, except for a glvalue
+    // derived-to-base conversion, which we handle below.
+    cv3T3 = ICS.Standard.getToType(2);
+    VK = VK_RValue;
+  }
+
+  //   If the converted initializer is a prvalue, its type T4 is adjusted to
+  //   type "cv1 T4" and the temporary materialization conversion is applied.
+  //
+  // We adjust the cv-qualifications to match the reference regardless of
+  // whether we have a prvalue so that the AST records the change. In this
+  // case, T4 is "cv3 T3".
+  QualType cv1T4 = S.Context.getQualifiedType(cv3T3, cv1T1.getQualifiers());
+  if (cv1T4.getQualifiers() != cv3T3.getQualifiers())
+    Sequence.AddQualificationConversionStep(cv1T4, VK);
+  Sequence.AddReferenceBindingStep(cv1T4, VK == VK_RValue);
+  VK = IsLValueRef ? VK_LValue : VK_XValue;
+
+  if (NewDerivedToBase)
+    Sequence.AddDerivedToBaseCastStep(cv1T1, VK);
+  else if (NewObjCConversion)
+    Sequence.AddObjCObjectConversionStep(cv1T1);
+
+  return OR_Success;
+}
+
+static void CheckCXX98CompatAccessibleCopy(Sema &S,
+                                           const InitializedEntity &Entity,
+                                           Expr *CurInitExpr);
+
+/// Attempt reference initialization (C++0x [dcl.init.ref])
+static void TryReferenceInitialization(Sema &S,
+                                       const InitializedEntity &Entity,
+                                       const InitializationKind &Kind,
+                                       Expr *Initializer,
+                                       InitializationSequence &Sequence) {
+  QualType DestType = Entity.getType();
+  QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
+  Qualifiers T1Quals;
+  QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
+  QualType cv2T2 = Initializer->getType();
+  Qualifiers T2Quals;
+  QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
+
+  // If the initializer is the address of an overloaded function, try
+  // to resolve the overloaded function. If all goes well, T2 is the
+  // type of the resulting function.
+  if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
+                                                   T1, Sequence))
+    return;
+
+  // Delegate everything else to a subfunction.
+  TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
+                                 T1Quals, cv2T2, T2, T2Quals, Sequence);
+}
+
+/// Determine whether an expression is a non-referenceable glvalue (one to
+/// which a reference can never bind). Attempting to bind a reference to
+/// such a glvalue will always create a temporary.
+static bool isNonReferenceableGLValue(Expr *E) {
+  return E->refersToBitField() || E->refersToVectorElement();
+}
+
+/// Reference initialization without resolving overloaded functions.
+static void TryReferenceInitializationCore(Sema &S,
+                                           const InitializedEntity &Entity,
+                                           const InitializationKind &Kind,
+                                           Expr *Initializer,
+                                           QualType cv1T1, QualType T1,
+                                           Qualifiers T1Quals,
+                                           QualType cv2T2, QualType T2,
+                                           Qualifiers T2Quals,
+                                           InitializationSequence &Sequence) {
+  QualType DestType = Entity.getType();
+  SourceLocation DeclLoc = Initializer->getBeginLoc();
+  // Compute some basic properties of the types and the initializer.
+  bool isLValueRef = DestType->isLValueReferenceType();
+  bool isRValueRef = !isLValueRef;
+  bool DerivedToBase = false;
+  bool ObjCConversion = false;
+  bool ObjCLifetimeConversion = false;
+  Expr::Classification InitCategory = Initializer->Classify(S.Context);
+  Sema::ReferenceCompareResult RefRelationship
+    = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase,
+                                     ObjCConversion, ObjCLifetimeConversion);
+
+  // C++0x [dcl.init.ref]p5:
+  //   A reference to type "cv1 T1" is initialized by an expression of type
+  //   "cv2 T2" as follows:
+  //
+  //     - If the reference is an lvalue reference and the initializer
+  //       expression
+  // Note the analogous bullet points for rvalue refs to functions. Because
+  // there are no function rvalues in C++, rvalue refs to functions are treated
+  // like lvalue refs.
+  OverloadingResult ConvOvlResult = OR_Success;
+  bool T1Function = T1->isFunctionType();
+  if (isLValueRef || T1Function) {
+    if (InitCategory.isLValue() && !isNonReferenceableGLValue(Initializer) &&
+        (RefRelationship == Sema::Ref_Compatible ||
+         (Kind.isCStyleOrFunctionalCast() &&
+          RefRelationship == Sema::Ref_Related))) {
+      //   - is an lvalue (but is not a bit-field), and "cv1 T1" is
+      //     reference-compatible with "cv2 T2," or
+      if (T1Quals != T2Quals)
+        // Convert to cv1 T2. This should only add qualifiers unless this is a
+        // c-style cast. The removal of qualifiers in that case notionally
+        // happens after the reference binding, but that doesn't matter.
+        Sequence.AddQualificationConversionStep(
+            S.Context.getQualifiedType(T2, T1Quals),
+            Initializer->getValueKind());
+      if (DerivedToBase)
+        Sequence.AddDerivedToBaseCastStep(cv1T1, VK_LValue);
+      else if (ObjCConversion)
+        Sequence.AddObjCObjectConversionStep(cv1T1);
+
+      // We only create a temporary here when binding a reference to a
+      // bit-field or vector element. Those cases are't supposed to be
+      // handled by this bullet, but the outcome is the same either way.
+      Sequence.AddReferenceBindingStep(cv1T1, false);
+      return;
+    }
+
+    //     - has a class type (i.e., T2 is a class type), where T1 is not
+    //       reference-related to T2, and can be implicitly converted to an
+    //       lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible
+    //       with "cv3 T3" (this conversion is selected by enumerating the
+    //       applicable conversion functions (13.3.1.6) and choosing the best
+    //       one through overload resolution (13.3)),
+    // If we have an rvalue ref to function type here, the rhs must be
+    // an rvalue. DR1287 removed the "implicitly" here.
+    if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() &&
+        (isLValueRef || InitCategory.isRValue())) {
+      ConvOvlResult = TryRefInitWithConversionFunction(
+          S, Entity, Kind, Initializer, /*AllowRValues*/ isRValueRef,
+          /*IsLValueRef*/ isLValueRef, Sequence);
+      if (ConvOvlResult == OR_Success)
+        return;
+      if (ConvOvlResult != OR_No_Viable_Function)
+        Sequence.SetOverloadFailure(
+            InitializationSequence::FK_ReferenceInitOverloadFailed,
+            ConvOvlResult);
+    }
+  }
+
+  //     - Otherwise, the reference shall be an lvalue reference to a
+  //       non-volatile const type (i.e., cv1 shall be const), or the reference
+  //       shall be an rvalue reference.
+  //       For address spaces, we interpret this to mean that an addr space
+  //       of a reference "cv1 T1" is a superset of addr space of "cv2 T2".
+  if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile() &&
+                       T1Quals.isAddressSpaceSupersetOf(T2Quals))) {
+    if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
+      Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
+    else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
+      Sequence.SetOverloadFailure(
+                        InitializationSequence::FK_ReferenceInitOverloadFailed,
+                                  ConvOvlResult);
+    else if (!InitCategory.isLValue())
+      Sequence.SetFailed(
+          T1Quals.isAddressSpaceSupersetOf(T2Quals)
+              ? InitializationSequence::
+                    FK_NonConstLValueReferenceBindingToTemporary
+              : InitializationSequence::FK_ReferenceInitDropsQualifiers);
+    else {
+      InitializationSequence::FailureKind FK;
+      switch (RefRelationship) {
+      case Sema::Ref_Compatible:
+        if (Initializer->refersToBitField())
+          FK = InitializationSequence::
+              FK_NonConstLValueReferenceBindingToBitfield;
+        else if (Initializer->refersToVectorElement())
+          FK = InitializationSequence::
+              FK_NonConstLValueReferenceBindingToVectorElement;
+        else
+          llvm_unreachable("unexpected kind of compatible initializer");
+        break;
+      case Sema::Ref_Related:
+        FK = InitializationSequence::FK_ReferenceInitDropsQualifiers;
+        break;
+      case Sema::Ref_Incompatible:
+        FK = InitializationSequence::
+            FK_NonConstLValueReferenceBindingToUnrelated;
+        break;
+      }
+      Sequence.SetFailed(FK);
+    }
+    return;
+  }
+
+  //    - If the initializer expression
+  //      - is an
+  // [<=14] xvalue (but not a bit-field), class prvalue, array prvalue, or
+  // [1z]   rvalue (but not a bit-field) or
+  //        function lvalue and "cv1 T1" is reference-compatible with "cv2 T2"
+  //
+  // Note: functions are handled above and below rather than here...
+  if (!T1Function &&
+      (RefRelationship == Sema::Ref_Compatible ||
+       (Kind.isCStyleOrFunctionalCast() &&
+        RefRelationship == Sema::Ref_Related)) &&
+      ((InitCategory.isXValue() && !isNonReferenceableGLValue(Initializer)) ||
+       (InitCategory.isPRValue() &&
+        (S.getLangOpts().CPlusPlus17 || T2->isRecordType() ||
+         T2->isArrayType())))) {
+    ExprValueKind ValueKind = InitCategory.isXValue() ? VK_XValue : VK_RValue;
+    if (InitCategory.isPRValue() && T2->isRecordType()) {
+      // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the
+      // compiler the freedom to perform a copy here or bind to the
+      // object, while C++0x requires that we bind directly to the
+      // object. Hence, we always bind to the object without making an
+      // extra copy. However, in C++03 requires that we check for the
+      // presence of a suitable copy constructor:
+      //
+      //   The constructor that would be used to make the copy shall
+      //   be callable whether or not the copy is actually done.
+      if (!S.getLangOpts().CPlusPlus11 && !S.getLangOpts().MicrosoftExt)
+        Sequence.AddExtraneousCopyToTemporary(cv2T2);
+      else if (S.getLangOpts().CPlusPlus11)
+        CheckCXX98CompatAccessibleCopy(S, Entity, Initializer);
+    }
+
+    // C++1z [dcl.init.ref]/5.2.1.2:
+    //   If the converted initializer is a prvalue, its type T4 is adjusted
+    //   to type "cv1 T4" and the temporary materialization conversion is
+    //   applied.
+    // Postpone address space conversions to after the temporary materialization
+    // conversion to allow creating temporaries in the alloca address space.
+    auto T1QualsIgnoreAS = T1Quals;
+    auto T2QualsIgnoreAS = T2Quals;
+    if (T1Quals.getAddressSpace() != T2Quals.getAddressSpace()) {
+      T1QualsIgnoreAS.removeAddressSpace();
+      T2QualsIgnoreAS.removeAddressSpace();
+    }
+    QualType cv1T4 = S.Context.getQualifiedType(cv2T2, T1QualsIgnoreAS);
+    if (T1QualsIgnoreAS != T2QualsIgnoreAS)
+      Sequence.AddQualificationConversionStep(cv1T4, ValueKind);
+    Sequence.AddReferenceBindingStep(cv1T4, ValueKind == VK_RValue);
+    ValueKind = isLValueRef ? VK_LValue : VK_XValue;
+    // Add addr space conversion if required.
+    if (T1Quals.getAddressSpace() != T2Quals.getAddressSpace()) {
+      auto T4Quals = cv1T4.getQualifiers();
+      T4Quals.addAddressSpace(T1Quals.getAddressSpace());
+      QualType cv1T4WithAS = S.Context.getQualifiedType(T2, T4Quals);
+      Sequence.AddQualificationConversionStep(cv1T4WithAS, ValueKind);
+    }
+
+    //   In any case, the reference is bound to the resulting glvalue (or to
+    //   an appropriate base class subobject).
+    if (DerivedToBase)
+      Sequence.AddDerivedToBaseCastStep(cv1T1, ValueKind);
+    else if (ObjCConversion)
+      Sequence.AddObjCObjectConversionStep(cv1T1);
+    return;
+  }
+
+  //       - has a class type (i.e., T2 is a class type), where T1 is not
+  //         reference-related to T2, and can be implicitly converted to an
+  //         xvalue, class prvalue, or function lvalue of type "cv3 T3",
+  //         where "cv1 T1" is reference-compatible with "cv3 T3",
+  //
+  // DR1287 removes the "implicitly" here.
+  if (T2->isRecordType()) {
+    if (RefRelationship == Sema::Ref_Incompatible) {
+      ConvOvlResult = TryRefInitWithConversionFunction(
+          S, Entity, Kind, Initializer, /*AllowRValues*/ true,
+          /*IsLValueRef*/ isLValueRef, Sequence);
+      if (ConvOvlResult)
+        Sequence.SetOverloadFailure(
+            InitializationSequence::FK_ReferenceInitOverloadFailed,
+            ConvOvlResult);
+
+      return;
+    }
+
+    if (RefRelationship == Sema::Ref_Compatible &&
+        isRValueRef && InitCategory.isLValue()) {
+      Sequence.SetFailed(
+        InitializationSequence::FK_RValueReferenceBindingToLValue);
+      return;
+    }
+
+    Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
+    return;
+  }
+
+  //      - Otherwise, a temporary of type "cv1 T1" is created and initialized
+  //        from the initializer expression using the rules for a non-reference
+  //        copy-initialization (8.5). The reference is then bound to the
+  //        temporary. [...]
+
+  // Ignore address space of reference type at this point and perform address
+  // space conversion after the reference binding step.
+  QualType cv1T1IgnoreAS =
+      T1Quals.hasAddressSpace()
+          ? S.Context.getQualifiedType(T1, T1Quals.withoutAddressSpace())
+          : cv1T1;
+
+  InitializedEntity TempEntity =
+      InitializedEntity::InitializeTemporary(cv1T1IgnoreAS);
+
+  // FIXME: Why do we use an implicit conversion here rather than trying
+  // copy-initialization?
+  ImplicitConversionSequence ICS
+    = S.TryImplicitConversion(Initializer, TempEntity.getType(),
+                              /*SuppressUserConversions=*/false,
+                              /*AllowExplicit=*/false,
+                              /*FIXME:InOverloadResolution=*/false,
+                              /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
+                              /*AllowObjCWritebackConversion=*/false);
+
+  if (ICS.isBad()) {
+    // FIXME: Use the conversion function set stored in ICS to turn
+    // this into an overloading ambiguity diagnostic. However, we need
+    // to keep that set as an OverloadCandidateSet rather than as some
+    // other kind of set.
+    if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
+      Sequence.SetOverloadFailure(
+                        InitializationSequence::FK_ReferenceInitOverloadFailed,
+                                  ConvOvlResult);
+    else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
+      Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
+    else
+      Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed);
+    return;
+  } else {
+    Sequence.AddConversionSequenceStep(ICS, TempEntity.getType());
+  }
+
+  //        [...] If T1 is reference-related to T2, cv1 must be the
+  //        same cv-qualification as, or greater cv-qualification
+  //        than, cv2; otherwise, the program is ill-formed.
+  unsigned T1CVRQuals = T1Quals.getCVRQualifiers();
+  unsigned T2CVRQuals = T2Quals.getCVRQualifiers();
+  if ((RefRelationship == Sema::Ref_Related &&
+       (T1CVRQuals | T2CVRQuals) != T1CVRQuals) ||
+      !T1Quals.isAddressSpaceSupersetOf(T2Quals)) {
+    Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
+    return;
+  }
+
+  //   [...] If T1 is reference-related to T2 and the reference is an rvalue
+  //   reference, the initializer expression shall not be an lvalue.
+  if (RefRelationship >= Sema::Ref_Related && !isLValueRef &&
+      InitCategory.isLValue()) {
+    Sequence.SetFailed(
+                    InitializationSequence::FK_RValueReferenceBindingToLValue);
+    return;
+  }
+
+  Sequence.AddReferenceBindingStep(cv1T1IgnoreAS, /*BindingTemporary=*/true);
+
+  if (T1Quals.hasAddressSpace()) {
+    if (!Qualifiers::isAddressSpaceSupersetOf(T1Quals.getAddressSpace(),
+                                              LangAS::Default)) {
+      Sequence.SetFailed(
+          InitializationSequence::FK_ReferenceAddrspaceMismatchTemporary);
+      return;
+    }
+    Sequence.AddQualificationConversionStep(cv1T1, isLValueRef ? VK_LValue
+                                                               : VK_XValue);
+  }
+}
+
+/// Attempt character array initialization from a string literal
+/// (C++ [dcl.init.string], C99 6.7.8).
+static void TryStringLiteralInitialization(Sema &S,
+                                           const InitializedEntity &Entity,
+                                           const InitializationKind &Kind,
+                                           Expr *Initializer,
+                                       InitializationSequence &Sequence) {
+  Sequence.AddStringInitStep(Entity.getType());
+}
+
+/// Attempt value initialization (C++ [dcl.init]p7).
+static void TryValueInitialization(Sema &S,
+                                   const InitializedEntity &Entity,
+                                   const InitializationKind &Kind,
+                                   InitializationSequence &Sequence,
+                                   InitListExpr *InitList) {
+  assert((!InitList || InitList->getNumInits() == 0) &&
+         "Shouldn't use value-init for non-empty init lists");
+
+  // C++98 [dcl.init]p5, C++11 [dcl.init]p7:
+  //
+  //   To value-initialize an object of type T means:
+  QualType T = Entity.getType();
+
+  //     -- if T is an array type, then each element is value-initialized;
+  T = S.Context.getBaseElementType(T);
+
+  if (const RecordType *RT = T->getAs<RecordType>()) {
+    if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
+      bool NeedZeroInitialization = true;
+      // C++98:
+      // -- if T is a class type (clause 9) with a user-declared constructor
+      //    (12.1), then the default constructor for T is called (and the
+      //    initialization is ill-formed if T has no accessible default
+      //    constructor);
+      // C++11:
+      // -- if T is a class type (clause 9) with either no default constructor
+      //    (12.1 [class.ctor]) or a default constructor that is user-provided
+      //    or deleted, then the object is default-initialized;
+      //
+      // Note that the C++11 rule is the same as the C++98 rule if there are no
+      // defaulted or deleted constructors, so we just use it unconditionally.
+      CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl);
+      if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted())
+        NeedZeroInitialization = false;
+
+      // -- if T is a (possibly cv-qualified) non-union class type without a
+      //    user-provided or deleted default constructor, then the object is
+      //    zero-initialized and, if T has a non-trivial default constructor,
+      //    default-initialized;
+      // The 'non-union' here was removed by DR1502. The 'non-trivial default
+      // constructor' part was removed by DR1507.
+      if (NeedZeroInitialization)
+        Sequence.AddZeroInitializationStep(Entity.getType());
+
+      // C++03:
+      // -- if T is a non-union class type without a user-declared constructor,
+      //    then every non-static data member and base class component of T is
+      //    value-initialized;
+      // [...] A program that calls for [...] value-initialization of an
+      // entity of reference type is ill-formed.
+      //
+      // C++11 doesn't need this handling, because value-initialization does not
+      // occur recursively there, and the implicit default constructor is
+      // defined as deleted in the problematic cases.
+      if (!S.getLangOpts().CPlusPlus11 &&
+          ClassDecl->hasUninitializedReferenceMember()) {
+        Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForReference);
+        return;
+      }
+
+      // If this is list-value-initialization, pass the empty init list on when
+      // building the constructor call. This affects the semantics of a few
+      // things (such as whether an explicit default constructor can be called).
+      Expr *InitListAsExpr = InitList;
+      MultiExprArg Args(&InitListAsExpr, InitList ? 1 : 0);
+      bool InitListSyntax = InitList;
+
+      // FIXME: Instead of creating a CXXConstructExpr of array type here,
+      // wrap a class-typed CXXConstructExpr in an ArrayInitLoopExpr.
+      return TryConstructorInitialization(
+          S, Entity, Kind, Args, T, Entity.getType(), Sequence, InitListSyntax);
+    }
+  }
+
+  Sequence.AddZeroInitializationStep(Entity.getType());
+}
+
+/// Attempt default initialization (C++ [dcl.init]p6).
+static void TryDefaultInitialization(Sema &S,
+                                     const InitializedEntity &Entity,
+                                     const InitializationKind &Kind,
+                                     InitializationSequence &Sequence) {
+  assert(Kind.getKind() == InitializationKind::IK_Default);
+
+  // C++ [dcl.init]p6:
+  //   To default-initialize an object of type T means:
+  //     - if T is an array type, each element is default-initialized;
+  QualType DestType = S.Context.getBaseElementType(Entity.getType());
+
+  //     - if T is a (possibly cv-qualified) class type (Clause 9), the default
+  //       constructor for T is called (and the initialization is ill-formed if
+  //       T has no accessible default constructor);
+  if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) {
+    TryConstructorInitialization(S, Entity, Kind, None, DestType,
+                                 Entity.getType(), Sequence);
+    return;
+  }
+
+  //     - otherwise, no initialization is performed.
+
+  //   If a program calls for the default initialization of an object of
+  //   a const-qualified type T, T shall be a class type with a user-provided
+  //   default constructor.
+  if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) {
+    if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
+      Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
+    return;
+  }
+
+  // If the destination type has a lifetime property, zero-initialize it.
+  if (DestType.getQualifiers().hasObjCLifetime()) {
+    Sequence.AddZeroInitializationStep(Entity.getType());
+    return;
+  }
+}
+
+/// Attempt a user-defined conversion between two types (C++ [dcl.init]),
+/// which enumerates all conversion functions and performs overload resolution
+/// to select the best.
+static void TryUserDefinedConversion(Sema &S,
+                                     QualType DestType,
+                                     const InitializationKind &Kind,
+                                     Expr *Initializer,
+                                     InitializationSequence &Sequence,
+                                     bool TopLevelOfInitList) {
+  assert(!DestType->isReferenceType() && "References are handled elsewhere");
+  QualType SourceType = Initializer->getType();
+  assert((DestType->isRecordType() || SourceType->isRecordType()) &&
+         "Must have a class type to perform a user-defined conversion");
+
+  // Build the candidate set directly in the initialization sequence
+  // structure, so that it will persist if we fail.
+  OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
+  CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
+  CandidateSet.setDestAS(DestType.getQualifiers().getAddressSpace());
+
+  // Determine whether we are allowed to call explicit constructors or
+  // explicit conversion operators.
+  bool AllowExplicit = Kind.AllowExplicit();
+
+  if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) {
+    // The type we're converting to is a class type. Enumerate its constructors
+    // to see if there is a suitable conversion.
+    CXXRecordDecl *DestRecordDecl
+      = cast<CXXRecordDecl>(DestRecordType->getDecl());
+
+    // Try to complete the type we're converting to.
+    if (S.isCompleteType(Kind.getLocation(), DestType)) {
+      for (NamedDecl *D : S.LookupConstructors(DestRecordDecl)) {
+        auto Info = getConstructorInfo(D);
+        if (!Info.Constructor)
+          continue;
+
+        if (!Info.Constructor->isInvalidDecl() &&
+            Info.Constructor->isConvertingConstructor(AllowExplicit)) {
+          if (Info.ConstructorTmpl)
+            S.AddTemplateOverloadCandidate(
+                Info.ConstructorTmpl, Info.FoundDecl,
+                /*ExplicitArgs*/ nullptr, Initializer, CandidateSet,
+                /*SuppressUserConversions=*/true,
+                /*PartialOverloading*/ false, AllowExplicit);
+          else
+            S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
+                                   Initializer, CandidateSet,
+                                   /*SuppressUserConversions=*/true,
+                                   /*PartialOverloading*/ false, AllowExplicit);
+        }
+      }
+    }
+  }
+
+  SourceLocation DeclLoc = Initializer->getBeginLoc();
+
+  if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) {
+    // The type we're converting from is a class type, enumerate its conversion
+    // functions.
+
+    // We can only enumerate the conversion functions for a complete type; if
+    // the type isn't complete, simply skip this step.
+    if (S.isCompleteType(DeclLoc, SourceType)) {
+      CXXRecordDecl *SourceRecordDecl
+        = cast<CXXRecordDecl>(SourceRecordType->getDecl());
+
+      const auto &Conversions =
+          SourceRecordDecl->getVisibleConversionFunctions();
+      for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
+        NamedDecl *D = *I;
+        CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
+        if (isa<UsingShadowDecl>(D))
+          D = cast<UsingShadowDecl>(D)->getTargetDecl();
+
+        FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
+        CXXConversionDecl *Conv;
+        if (ConvTemplate)
+          Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
+        else
+          Conv = cast<CXXConversionDecl>(D);
+
+        if (AllowExplicit || !Conv->isExplicit()) {
+          if (ConvTemplate)
+            S.AddTemplateConversionCandidate(
+                ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
+                CandidateSet, AllowExplicit, AllowExplicit);
+          else
+            S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Initializer,
+                                     DestType, CandidateSet, AllowExplicit,
+                                     AllowExplicit);
+        }
+      }
+    }
+  }
+
+  // Perform overload resolution. If it fails, return the failed result.
+  OverloadCandidateSet::iterator Best;
+  if (OverloadingResult Result
+        = CandidateSet.BestViableFunction(S, DeclLoc, Best)) {
+    Sequence.SetOverloadFailure(
+                        InitializationSequence::FK_UserConversionOverloadFailed,
+                                Result);
+    return;
+  }
+
+  FunctionDecl *Function = Best->Function;
+  Function->setReferenced();
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
+  if (isa<CXXConstructorDecl>(Function)) {
+    // Add the user-defined conversion step. Any cv-qualification conversion is
+    // subsumed by the initialization. Per DR5, the created temporary is of the
+    // cv-unqualified type of the destination.
+    Sequence.AddUserConversionStep(Function, Best->FoundDecl,
+                                   DestType.getUnqualifiedType(),
+                                   HadMultipleCandidates);
+
+    // C++14 and before:
+    //   - if the function is a constructor, the call initializes a temporary
+    //     of the cv-unqualified version of the destination type. The [...]
+    //     temporary [...] is then used to direct-initialize, according to the
+    //     rules above, the object that is the destination of the
+    //     copy-initialization.
+    // Note that this just performs a simple object copy from the temporary.
+    //
+    // C++17:
+    //   - if the function is a constructor, the call is a prvalue of the
+    //     cv-unqualified version of the destination type whose return object
+    //     is initialized by the constructor. The call is used to
+    //     direct-initialize, according to the rules above, the object that
+    //     is the destination of the copy-initialization.
+    // Therefore we need to do nothing further.
+    //
+    // FIXME: Mark this copy as extraneous.
+    if (!S.getLangOpts().CPlusPlus17)
+      Sequence.AddFinalCopy(DestType);
+    else if (DestType.hasQualifiers())
+      Sequence.AddQualificationConversionStep(DestType, VK_RValue);
+    return;
+  }
+
+  // Add the user-defined conversion step that calls the conversion function.
+  QualType ConvType = Function->getCallResultType();
+  Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType,
+                                 HadMultipleCandidates);
+
+  if (ConvType->getAs<RecordType>()) {
+    //   The call is used to direct-initialize [...] the object that is the
+    //   destination of the copy-initialization.
+    //
+    // In C++17, this does not call a constructor if we enter /17.6.1:
+    //   - If the initializer expression is a prvalue and the cv-unqualified
+    //     version of the source type is the same as the class of the
+    //     destination [... do not make an extra copy]
+    //
+    // FIXME: Mark this copy as extraneous.
+    if (!S.getLangOpts().CPlusPlus17 ||
+        Function->getReturnType()->isReferenceType() ||
+        !S.Context.hasSameUnqualifiedType(ConvType, DestType))
+      Sequence.AddFinalCopy(DestType);
+    else if (!S.Context.hasSameType(ConvType, DestType))
+      Sequence.AddQualificationConversionStep(DestType, VK_RValue);
+    return;
+  }
+
+  // If the conversion following the call to the conversion function
+  // is interesting, add it as a separate step.
+  if (Best->FinalConversion.First || Best->FinalConversion.Second ||
+      Best->FinalConversion.Third) {
+    ImplicitConversionSequence ICS;
+    ICS.setStandard();
+    ICS.Standard = Best->FinalConversion;
+    Sequence.AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
+  }
+}
+
+/// An egregious hack for compatibility with libstdc++-4.2: in <tr1/hashtable>,
+/// a function with a pointer return type contains a 'return false;' statement.
+/// In C++11, 'false' is not a null pointer, so this breaks the build of any
+/// code using that header.
+///
+/// Work around this by treating 'return false;' as zero-initializing the result
+/// if it's used in a pointer-returning function in a system header.
+static bool isLibstdcxxPointerReturnFalseHack(Sema &S,
+                                              const InitializedEntity &Entity,
+                                              const Expr *Init) {
+  return S.getLangOpts().CPlusPlus11 &&
+         Entity.getKind() == InitializedEntity::EK_Result &&
+         Entity.getType()->isPointerType() &&
+         isa<CXXBoolLiteralExpr>(Init) &&
+         !cast<CXXBoolLiteralExpr>(Init)->getValue() &&
+         S.getSourceManager().isInSystemHeader(Init->getExprLoc());
+}
+
+/// The non-zero enum values here are indexes into diagnostic alternatives.
+enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar };
+
+/// Determines whether this expression is an acceptable ICR source.
+static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e,
+                                         bool isAddressOf, bool &isWeakAccess) {
+  // Skip parens.
+  e = e->IgnoreParens();
+
+  // Skip address-of nodes.
+  if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
+    if (op->getOpcode() == UO_AddrOf)
+      return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true,
+                                isWeakAccess);
+
+  // Skip certain casts.
+  } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) {
+    switch (ce->getCastKind()) {
+    case CK_Dependent:
+    case CK_BitCast:
+    case CK_LValueBitCast:
+    case CK_NoOp:
+      return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf, isWeakAccess);
+
+    case CK_ArrayToPointerDecay:
+      return IIK_nonscalar;
+
+    case CK_NullToPointer:
+      return IIK_okay;
+
+    default:
+      break;
+    }
+
+  // If we have a declaration reference, it had better be a local variable.
+  } else if (isa<DeclRefExpr>(e)) {
+    // set isWeakAccess to true, to mean that there will be an implicit
+    // load which requires a cleanup.
+    if (e->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
+      isWeakAccess = true;
+
+    if (!isAddressOf) return IIK_nonlocal;
+
+    VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl());
+    if (!var) return IIK_nonlocal;
+
+    return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal);
+
+  // If we have a conditional operator, check both sides.
+  } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) {
+    if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf,
+                                                isWeakAccess))
+      return iik;
+
+    return isInvalidICRSource(C, cond->getRHS(), isAddressOf, isWeakAccess);
+
+  // These are never scalar.
+  } else if (isa<ArraySubscriptExpr>(e)) {
+    return IIK_nonscalar;
+
+  // Otherwise, it needs to be a null pointer constant.
+  } else {
+    return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull)
+            ? IIK_okay : IIK_nonlocal);
+  }
+
+  return IIK_nonlocal;
+}
+
+/// Check whether the given expression is a valid operand for an
+/// indirect copy/restore.
+static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) {
+  assert(src->isRValue());
+  bool isWeakAccess = false;
+  InvalidICRKind iik = isInvalidICRSource(S.Context, src, false, isWeakAccess);
+  // If isWeakAccess to true, there will be an implicit
+  // load which requires a cleanup.
+  if (S.getLangOpts().ObjCAutoRefCount && isWeakAccess)
+    S.Cleanup.setExprNeedsCleanups(true);
+
+  if (iik == IIK_okay) return;
+
+  S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback)
+    << ((unsigned) iik - 1)  // shift index into diagnostic explanations
+    << src->getSourceRange();
+}
+
+/// Determine whether we have compatible array types for the
+/// purposes of GNU by-copy array initialization.
+static bool hasCompatibleArrayTypes(ASTContext &Context, const ArrayType *Dest,
+                                    const ArrayType *Source) {
+  // If the source and destination array types are equivalent, we're
+  // done.
+  if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0)))
+    return true;
+
+  // Make sure that the element types are the same.
+  if (!Context.hasSameType(Dest->getElementType(), Source->getElementType()))
+    return false;
+
+  // The only mismatch we allow is when the destination is an
+  // incomplete array type and the source is a constant array type.
+  return Source->isConstantArrayType() && Dest->isIncompleteArrayType();
+}
+
+static bool tryObjCWritebackConversion(Sema &S,
+                                       InitializationSequence &Sequence,
+                                       const InitializedEntity &Entity,
+                                       Expr *Initializer) {
+  bool ArrayDecay = false;
+  QualType ArgType = Initializer->getType();
+  QualType ArgPointee;
+  if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) {
+    ArrayDecay = true;
+    ArgPointee = ArgArrayType->getElementType();
+    ArgType = S.Context.getPointerType(ArgPointee);
+  }
+
+  // Handle write-back conversion.
+  QualType ConvertedArgType;
+  if (!S.isObjCWritebackConversion(ArgType, Entity.getType(),
+                                   ConvertedArgType))
+    return false;
+
+  // We should copy unless we're passing to an argument explicitly
+  // marked 'out'.
+  bool ShouldCopy = true;
+  if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
+    ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
+
+  // Do we need an lvalue conversion?
+  if (ArrayDecay || Initializer->isGLValue()) {
+    ImplicitConversionSequence ICS;
+    ICS.setStandard();
+    ICS.Standard.setAsIdentityConversion();
+
+    QualType ResultType;
+    if (ArrayDecay) {
+      ICS.Standard.First = ICK_Array_To_Pointer;
+      ResultType = S.Context.getPointerType(ArgPointee);
+    } else {
+      ICS.Standard.First = ICK_Lvalue_To_Rvalue;
+      ResultType = Initializer->getType().getNonLValueExprType(S.Context);
+    }
+
+    Sequence.AddConversionSequenceStep(ICS, ResultType);
+  }
+
+  Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy);
+  return true;
+}
+
+static bool TryOCLSamplerInitialization(Sema &S,
+                                        InitializationSequence &Sequence,
+                                        QualType DestType,
+                                        Expr *Initializer) {
+  if (!S.getLangOpts().OpenCL || !DestType->isSamplerT() ||
+      (!Initializer->isIntegerConstantExpr(S.Context) &&
+      !Initializer->getType()->isSamplerT()))
+    return false;
+
+  Sequence.AddOCLSamplerInitStep(DestType);
+  return true;
+}
+
+static bool IsZeroInitializer(Expr *Initializer, Sema &S) {
+  return Initializer->isIntegerConstantExpr(S.getASTContext()) &&
+    (Initializer->EvaluateKnownConstInt(S.getASTContext()) == 0);
+}
+
+static bool TryOCLZeroOpaqueTypeInitialization(Sema &S,
+                                               InitializationSequence &Sequence,
+                                               QualType DestType,
+                                               Expr *Initializer) {
+  if (!S.getLangOpts().OpenCL)
+    return false;
+
+  //
+  // OpenCL 1.2 spec, s6.12.10
+  //
+  // The event argument can also be used to associate the
+  // async_work_group_copy with a previous async copy allowing
+  // an event to be shared by multiple async copies; otherwise
+  // event should be zero.
+  //
+  if (DestType->isEventT() || DestType->isQueueT()) {
+    if (!IsZeroInitializer(Initializer, S))
+      return false;
+
+    Sequence.AddOCLZeroOpaqueTypeStep(DestType);
+    return true;
+  }
+
+  // We should allow zero initialization for all types defined in the
+  // cl_intel_device_side_avc_motion_estimation extension, except
+  // intel_sub_group_avc_mce_payload_t and intel_sub_group_avc_mce_result_t.
+  if (S.getOpenCLOptions().isEnabled(
+          "cl_intel_device_side_avc_motion_estimation") &&
+      DestType->isOCLIntelSubgroupAVCType()) {
+    if (DestType->isOCLIntelSubgroupAVCMcePayloadType() ||
+        DestType->isOCLIntelSubgroupAVCMceResultType())
+      return false;
+    if (!IsZeroInitializer(Initializer, S))
+      return false;
+
+    Sequence.AddOCLZeroOpaqueTypeStep(DestType);
+    return true;
+  }
+
+  return false;
+}
+
+InitializationSequence::InitializationSequence(Sema &S,
+                                               const InitializedEntity &Entity,
+                                               const InitializationKind &Kind,
+                                               MultiExprArg Args,
+                                               bool TopLevelOfInitList,
+                                               bool TreatUnavailableAsInvalid)
+    : FailedCandidateSet(Kind.getLocation(), OverloadCandidateSet::CSK_Normal) {
+  InitializeFrom(S, Entity, Kind, Args, TopLevelOfInitList,
+                 TreatUnavailableAsInvalid);
+}
+
+/// Tries to get a FunctionDecl out of `E`. If it succeeds and we can take the
+/// address of that function, this returns true. Otherwise, it returns false.
+static bool isExprAnUnaddressableFunction(Sema &S, const Expr *E) {
+  auto *DRE = dyn_cast<DeclRefExpr>(E);
+  if (!DRE || !isa<FunctionDecl>(DRE->getDecl()))
+    return false;
+
+  return !S.checkAddressOfFunctionIsAvailable(
+      cast<FunctionDecl>(DRE->getDecl()));
+}
+
+/// Determine whether we can perform an elementwise array copy for this kind
+/// of entity.
+static bool canPerformArrayCopy(const InitializedEntity &Entity) {
+  switch (Entity.getKind()) {
+  case InitializedEntity::EK_LambdaCapture:
+    // C++ [expr.prim.lambda]p24:
+    //   For array members, the array elements are direct-initialized in
+    //   increasing subscript order.
+    return true;
+
+  case InitializedEntity::EK_Variable:
+    // C++ [dcl.decomp]p1:
+    //   [...] each element is copy-initialized or direct-initialized from the
+    //   corresponding element of the assignment-expression [...]
+    return isa<DecompositionDecl>(Entity.getDecl());
+
+  case InitializedEntity::EK_Member:
+    // C++ [class.copy.ctor]p14:
+    //   - if the member is an array, each element is direct-initialized with
+    //     the corresponding subobject of x
+    return Entity.isImplicitMemberInitializer();
+
+  case InitializedEntity::EK_ArrayElement:
+    // All the above cases are intended to apply recursively, even though none
+    // of them actually say that.
+    if (auto *E = Entity.getParent())
+      return canPerformArrayCopy(*E);
+    break;
+
+  default:
+    break;
+  }
+
+  return false;
+}
+
+void InitializationSequence::InitializeFrom(Sema &S,
+                                            const InitializedEntity &Entity,
+                                            const InitializationKind &Kind,
+                                            MultiExprArg Args,
+                                            bool TopLevelOfInitList,
+                                            bool TreatUnavailableAsInvalid) {
+  ASTContext &Context = S.Context;
+
+  // Eliminate non-overload placeholder types in the arguments.  We
+  // need to do this before checking whether types are dependent
+  // because lowering a pseudo-object expression might well give us
+  // something of dependent type.
+  for (unsigned I = 0, E = Args.size(); I != E; ++I)
+    if (Args[I]->getType()->isNonOverloadPlaceholderType()) {
+      // FIXME: should we be doing this here?
+      ExprResult result = S.CheckPlaceholderExpr(Args[I]);
+      if (result.isInvalid()) {
+        SetFailed(FK_PlaceholderType);
+        return;
+      }
+      Args[I] = result.get();
+    }
+
+  // C++0x [dcl.init]p16:
+  //   The semantics of initializers are as follows. The destination type is
+  //   the type of the object or reference being initialized and the source
+  //   type is the type of the initializer expression. The source type is not
+  //   defined when the initializer is a braced-init-list or when it is a
+  //   parenthesized list of expressions.
+  QualType DestType = Entity.getType();
+
+  if (DestType->isDependentType() ||
+      Expr::hasAnyTypeDependentArguments(Args)) {
+    SequenceKind = DependentSequence;
+    return;
+  }
+
+  // Almost everything is a normal sequence.
+  setSequenceKind(NormalSequence);
+
+  QualType SourceType;
+  Expr *Initializer = nullptr;
+  if (Args.size() == 1) {
+    Initializer = Args[0];
+    if (S.getLangOpts().ObjC) {
+      if (S.CheckObjCBridgeRelatedConversions(Initializer->getBeginLoc(),
+                                              DestType, Initializer->getType(),
+                                              Initializer) ||
+          S.ConversionToObjCStringLiteralCheck(DestType, Initializer))
+        Args[0] = Initializer;
+    }
+    if (!isa<InitListExpr>(Initializer))
+      SourceType = Initializer->getType();
+  }
+
+  //     - If the initializer is a (non-parenthesized) braced-init-list, the
+  //       object is list-initialized (8.5.4).
+  if (Kind.getKind() != InitializationKind::IK_Direct) {
+    if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) {
+      TryListInitialization(S, Entity, Kind, InitList, *this,
+                            TreatUnavailableAsInvalid);
+      return;
+    }
+  }
+
+  //     - If the destination type is a reference type, see 8.5.3.
+  if (DestType->isReferenceType()) {
+    // C++0x [dcl.init.ref]p1:
+    //   A variable declared to be a T& or T&&, that is, "reference to type T"
+    //   (8.3.2), shall be initialized by an object, or function, of type T or
+    //   by an object that can be converted into a T.
+    // (Therefore, multiple arguments are not permitted.)
+    if (Args.size() != 1)
+      SetFailed(FK_TooManyInitsForReference);
+    // C++17 [dcl.init.ref]p5:
+    //   A reference [...] is initialized by an expression [...] as follows:
+    // If the initializer is not an expression, presumably we should reject,
+    // but the standard fails to actually say so.
+    else if (isa<InitListExpr>(Args[0]))
+      SetFailed(FK_ParenthesizedListInitForReference);
+    else
+      TryReferenceInitialization(S, Entity, Kind, Args[0], *this);
+    return;
+  }
+
+  //     - If the initializer is (), the object is value-initialized.
+  if (Kind.getKind() == InitializationKind::IK_Value ||
+      (Kind.getKind() == InitializationKind::IK_Direct && Args.empty())) {
+    TryValueInitialization(S, Entity, Kind, *this);
+    return;
+  }
+
+  // Handle default initialization.
+  if (Kind.getKind() == InitializationKind::IK_Default) {
+    TryDefaultInitialization(S, Entity, Kind, *this);
+    return;
+  }
+
+  //     - If the destination type is an array of characters, an array of
+  //       char16_t, an array of char32_t, or an array of wchar_t, and the
+  //       initializer is a string literal, see 8.5.2.
+  //     - Otherwise, if the destination type is an array, the program is
+  //       ill-formed.
+  if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) {
+    if (Initializer && isa<VariableArrayType>(DestAT)) {
+      SetFailed(FK_VariableLengthArrayHasInitializer);
+      return;
+    }
+
+    if (Initializer) {
+      switch (IsStringInit(Initializer, DestAT, Context)) {
+      case SIF_None:
+        TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this);
+        return;
+      case SIF_NarrowStringIntoWideChar:
+        SetFailed(FK_NarrowStringIntoWideCharArray);
+        return;
+      case SIF_WideStringIntoChar:
+        SetFailed(FK_WideStringIntoCharArray);
+        return;
+      case SIF_IncompatWideStringIntoWideChar:
+        SetFailed(FK_IncompatWideStringIntoWideChar);
+        return;
+      case SIF_PlainStringIntoUTF8Char:
+        SetFailed(FK_PlainStringIntoUTF8Char);
+        return;
+      case SIF_UTF8StringIntoPlainChar:
+        SetFailed(FK_UTF8StringIntoPlainChar);
+        return;
+      case SIF_Other:
+        break;
+      }
+    }
+
+    // Some kinds of initialization permit an array to be initialized from
+    // another array of the same type, and perform elementwise initialization.
+    if (Initializer && isa<ConstantArrayType>(DestAT) &&
+        S.Context.hasSameUnqualifiedType(Initializer->getType(),
+                                         Entity.getType()) &&
+        canPerformArrayCopy(Entity)) {
+      // If source is a prvalue, use it directly.
+      if (Initializer->getValueKind() == VK_RValue) {
+        AddArrayInitStep(DestType, /*IsGNUExtension*/false);
+        return;
+      }
+
+      // Emit element-at-a-time copy loop.
+      InitializedEntity Element =
+          InitializedEntity::InitializeElement(S.Context, 0, Entity);
+      QualType InitEltT =
+          Context.getAsArrayType(Initializer->getType())->getElementType();
+      OpaqueValueExpr OVE(Initializer->getExprLoc(), InitEltT,
+                          Initializer->getValueKind(),
+                          Initializer->getObjectKind());
+      Expr *OVEAsExpr = &OVE;
+      InitializeFrom(S, Element, Kind, OVEAsExpr, TopLevelOfInitList,
+                     TreatUnavailableAsInvalid);
+      if (!Failed())
+        AddArrayInitLoopStep(Entity.getType(), InitEltT);
+      return;
+    }
+
+    // Note: as an GNU C extension, we allow initialization of an
+    // array from a compound literal that creates an array of the same
+    // type, so long as the initializer has no side effects.
+    if (!S.getLangOpts().CPlusPlus && Initializer &&
+        isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) &&
+        Initializer->getType()->isArrayType()) {
+      const ArrayType *SourceAT
+        = Context.getAsArrayType(Initializer->getType());
+      if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT))
+        SetFailed(FK_ArrayTypeMismatch);
+      else if (Initializer->HasSideEffects(S.Context))
+        SetFailed(FK_NonConstantArrayInit);
+      else {
+        AddArrayInitStep(DestType, /*IsGNUExtension*/true);
+      }
+    }
+    // Note: as a GNU C++ extension, we allow list-initialization of a
+    // class member of array type from a parenthesized initializer list.
+    else if (S.getLangOpts().CPlusPlus &&
+             Entity.getKind() == InitializedEntity::EK_Member &&
+             Initializer && isa<InitListExpr>(Initializer)) {
+      TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer),
+                            *this, TreatUnavailableAsInvalid);
+      AddParenthesizedArrayInitStep(DestType);
+    } else if (DestAT->getElementType()->isCharType())
+      SetFailed(FK_ArrayNeedsInitListOrStringLiteral);
+    else if (IsWideCharCompatible(DestAT->getElementType(), Context))
+      SetFailed(FK_ArrayNeedsInitListOrWideStringLiteral);
+    else
+      SetFailed(FK_ArrayNeedsInitList);
+
+    return;
+  }
+
+  // Determine whether we should consider writeback conversions for
+  // Objective-C ARC.
+  bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount &&
+         Entity.isParameterKind();
+
+  if (TryOCLSamplerInitialization(S, *this, DestType, Initializer))
+    return;
+
+  // We're at the end of the line for C: it's either a write-back conversion
+  // or it's a C assignment. There's no need to check anything else.
+  if (!S.getLangOpts().CPlusPlus) {
+    // If allowed, check whether this is an Objective-C writeback conversion.
+    if (allowObjCWritebackConversion &&
+        tryObjCWritebackConversion(S, *this, Entity, Initializer)) {
+      return;
+    }
+
+    if (TryOCLZeroOpaqueTypeInitialization(S, *this, DestType, Initializer))
+      return;
+
+    // Handle initialization in C
+    AddCAssignmentStep(DestType);
+    MaybeProduceObjCObject(S, *this, Entity);
+    return;
+  }
+
+  assert(S.getLangOpts().CPlusPlus);
+
+  //     - If the destination type is a (possibly cv-qualified) class type:
+  if (DestType->isRecordType()) {
+    //     - If the initialization is direct-initialization, or if it is
+    //       copy-initialization where the cv-unqualified version of the
+    //       source type is the same class as, or a derived class of, the
+    //       class of the destination, constructors are considered. [...]
+    if (Kind.getKind() == InitializationKind::IK_Direct ||
+        (Kind.getKind() == InitializationKind::IK_Copy &&
+         (Context.hasSameUnqualifiedType(SourceType, DestType) ||
+          S.IsDerivedFrom(Initializer->getBeginLoc(), SourceType, DestType))))
+      TryConstructorInitialization(S, Entity, Kind, Args,
+                                   DestType, DestType, *this);
+    //     - Otherwise (i.e., for the remaining copy-initialization cases),
+    //       user-defined conversion sequences that can convert from the source
+    //       type to the destination type or (when a conversion function is
+    //       used) to a derived class thereof are enumerated as described in
+    //       13.3.1.4, and the best one is chosen through overload resolution
+    //       (13.3).
+    else
+      TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
+                               TopLevelOfInitList);
+    return;
+  }
+
+  assert(Args.size() >= 1 && "Zero-argument case handled above");
+
+  // The remaining cases all need a source type.
+  if (Args.size() > 1) {
+    SetFailed(FK_TooManyInitsForScalar);
+    return;
+  } else if (isa<InitListExpr>(Args[0])) {
+    SetFailed(FK_ParenthesizedListInitForScalar);
+    return;
+  }
+
+  //    - Otherwise, if the source type is a (possibly cv-qualified) class
+  //      type, conversion functions are considered.
+  if (!SourceType.isNull() && SourceType->isRecordType()) {
+    // For a conversion to _Atomic(T) from either T or a class type derived
+    // from T, initialize the T object then convert to _Atomic type.
+    bool NeedAtomicConversion = false;
+    if (const AtomicType *Atomic = DestType->getAs<AtomicType>()) {
+      if (Context.hasSameUnqualifiedType(SourceType, Atomic->getValueType()) ||
+          S.IsDerivedFrom(Initializer->getBeginLoc(), SourceType,
+                          Atomic->getValueType())) {
+        DestType = Atomic->getValueType();
+        NeedAtomicConversion = true;
+      }
+    }
+
+    TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
+                             TopLevelOfInitList);
+    MaybeProduceObjCObject(S, *this, Entity);
+    if (!Failed() && NeedAtomicConversion)
+      AddAtomicConversionStep(Entity.getType());
+    return;
+  }
+
+  //    - Otherwise, the initial value of the object being initialized is the
+  //      (possibly converted) value of the initializer expression. Standard
+  //      conversions (Clause 4) will be used, if necessary, to convert the
+  //      initializer expression to the cv-unqualified version of the
+  //      destination type; no user-defined conversions are considered.
+
+  ImplicitConversionSequence ICS
+    = S.TryImplicitConversion(Initializer, DestType,
+                              /*SuppressUserConversions*/true,
+                              /*AllowExplicitConversions*/ false,
+                              /*InOverloadResolution*/ false,
+                              /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
+                              allowObjCWritebackConversion);
+
+  if (ICS.isStandard() &&
+      ICS.Standard.Second == ICK_Writeback_Conversion) {
+    // Objective-C ARC writeback conversion.
+
+    // We should copy unless we're passing to an argument explicitly
+    // marked 'out'.
+    bool ShouldCopy = true;
+    if (ParmVarDecl *Param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
+      ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
+
+    // If there was an lvalue adjustment, add it as a separate conversion.
+    if (ICS.Standard.First == ICK_Array_To_Pointer ||
+        ICS.Standard.First == ICK_Lvalue_To_Rvalue) {
+      ImplicitConversionSequence LvalueICS;
+      LvalueICS.setStandard();
+      LvalueICS.Standard.setAsIdentityConversion();
+      LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0));
+      LvalueICS.Standard.First = ICS.Standard.First;
+      AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0));
+    }
+
+    AddPassByIndirectCopyRestoreStep(DestType, ShouldCopy);
+  } else if (ICS.isBad()) {
+    DeclAccessPair dap;
+    if (isLibstdcxxPointerReturnFalseHack(S, Entity, Initializer)) {
+      AddZeroInitializationStep(Entity.getType());
+    } else if (Initializer->getType() == Context.OverloadTy &&
+               !S.ResolveAddressOfOverloadedFunction(Initializer, DestType,
+                                                     false, dap))
+      SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
+    else if (Initializer->getType()->isFunctionType() &&
+             isExprAnUnaddressableFunction(S, Initializer))
+      SetFailed(InitializationSequence::FK_AddressOfUnaddressableFunction);
+    else
+      SetFailed(InitializationSequence::FK_ConversionFailed);
+  } else {
+    AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
+
+    MaybeProduceObjCObject(S, *this, Entity);
+  }
+}
+
+InitializationSequence::~InitializationSequence() {
+  for (auto &S : Steps)
+    S.Destroy();
+}
+
+//===----------------------------------------------------------------------===//
+// Perform initialization
+//===----------------------------------------------------------------------===//
+static Sema::AssignmentAction
+getAssignmentAction(const InitializedEntity &Entity, bool Diagnose = false) {
+  switch(Entity.getKind()) {
+  case InitializedEntity::EK_Variable:
+  case InitializedEntity::EK_New:
+  case InitializedEntity::EK_Exception:
+  case InitializedEntity::EK_Base:
+  case InitializedEntity::EK_Delegating:
+    return Sema::AA_Initializing;
+
+  case InitializedEntity::EK_Parameter:
+    if (Entity.getDecl() &&
+        isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
+      return Sema::AA_Sending;
+
+    return Sema::AA_Passing;
+
+  case InitializedEntity::EK_Parameter_CF_Audited:
+    if (Entity.getDecl() &&
+      isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
+      return Sema::AA_Sending;
+
+    return !Diagnose ? Sema::AA_Passing : Sema::AA_Passing_CFAudited;
+
+  case InitializedEntity::EK_Result:
+  case InitializedEntity::EK_StmtExprResult: // FIXME: Not quite right.
+    return Sema::AA_Returning;
+
+  case InitializedEntity::EK_Temporary:
+  case InitializedEntity::EK_RelatedResult:
+    // FIXME: Can we tell apart casting vs. converting?
+    return Sema::AA_Casting;
+
+  case InitializedEntity::EK_Member:
+  case InitializedEntity::EK_Binding:
+  case InitializedEntity::EK_ArrayElement:
+  case InitializedEntity::EK_VectorElement:
+  case InitializedEntity::EK_ComplexElement:
+  case InitializedEntity::EK_BlockElement:
+  case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
+  case InitializedEntity::EK_LambdaCapture:
+  case InitializedEntity::EK_CompoundLiteralInit:
+    return Sema::AA_Initializing;
+  }
+
+  llvm_unreachable("Invalid EntityKind!");
+}
+
+/// Whether we should bind a created object as a temporary when
+/// initializing the given entity.
+static bool shouldBindAsTemporary(const InitializedEntity &Entity) {
+  switch (Entity.getKind()) {
+  case InitializedEntity::EK_ArrayElement:
+  case InitializedEntity::EK_Member:
+  case InitializedEntity::EK_Result:
+  case InitializedEntity::EK_StmtExprResult:
+  case InitializedEntity::EK_New:
+  case InitializedEntity::EK_Variable:
+  case InitializedEntity::EK_Base:
+  case InitializedEntity::EK_Delegating:
+  case InitializedEntity::EK_VectorElement:
+  case InitializedEntity::EK_ComplexElement:
+  case InitializedEntity::EK_Exception:
+  case InitializedEntity::EK_BlockElement:
+  case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
+  case InitializedEntity::EK_LambdaCapture:
+  case InitializedEntity::EK_CompoundLiteralInit:
+    return false;
+
+  case InitializedEntity::EK_Parameter:
+  case InitializedEntity::EK_Parameter_CF_Audited:
+  case InitializedEntity::EK_Temporary:
+  case InitializedEntity::EK_RelatedResult:
+  case InitializedEntity::EK_Binding:
+    return true;
+  }
+
+  llvm_unreachable("missed an InitializedEntity kind?");
+}
+
+/// Whether the given entity, when initialized with an object
+/// created for that initialization, requires destruction.
+static bool shouldDestroyEntity(const InitializedEntity &Entity) {
+  switch (Entity.getKind()) {
+    case InitializedEntity::EK_Result:
+    case InitializedEntity::EK_StmtExprResult:
+    case InitializedEntity::EK_New:
+    case InitializedEntity::EK_Base:
+    case InitializedEntity::EK_Delegating:
+    case InitializedEntity::EK_VectorElement:
+    case InitializedEntity::EK_ComplexElement:
+    case InitializedEntity::EK_BlockElement:
+    case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
+    case InitializedEntity::EK_LambdaCapture:
+      return false;
+
+    case InitializedEntity::EK_Member:
+    case InitializedEntity::EK_Binding:
+    case InitializedEntity::EK_Variable:
+    case InitializedEntity::EK_Parameter:
+    case InitializedEntity::EK_Parameter_CF_Audited:
+    case InitializedEntity::EK_Temporary:
+    case InitializedEntity::EK_ArrayElement:
+    case InitializedEntity::EK_Exception:
+    case InitializedEntity::EK_CompoundLiteralInit:
+    case InitializedEntity::EK_RelatedResult:
+      return true;
+  }
+
+  llvm_unreachable("missed an InitializedEntity kind?");
+}
+
+/// Get the location at which initialization diagnostics should appear.
+static SourceLocation getInitializationLoc(const InitializedEntity &Entity,
+                                           Expr *Initializer) {
+  switch (Entity.getKind()) {
+  case InitializedEntity::EK_Result:
+  case InitializedEntity::EK_StmtExprResult:
+    return Entity.getReturnLoc();
+
+  case InitializedEntity::EK_Exception:
+    return Entity.getThrowLoc();
+
+  case InitializedEntity::EK_Variable:
+  case InitializedEntity::EK_Binding:
+    return Entity.getDecl()->getLocation();
+
+  case InitializedEntity::EK_LambdaCapture:
+    return Entity.getCaptureLoc();
+
+  case InitializedEntity::EK_ArrayElement:
+  case InitializedEntity::EK_Member:
+  case InitializedEntity::EK_Parameter:
+  case InitializedEntity::EK_Parameter_CF_Audited:
+  case InitializedEntity::EK_Temporary:
+  case InitializedEntity::EK_New:
+  case InitializedEntity::EK_Base:
+  case InitializedEntity::EK_Delegating:
+  case InitializedEntity::EK_VectorElement:
+  case InitializedEntity::EK_ComplexElement:
+  case InitializedEntity::EK_BlockElement:
+  case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
+  case InitializedEntity::EK_CompoundLiteralInit:
+  case InitializedEntity::EK_RelatedResult:
+    return Initializer->getBeginLoc();
+  }
+  llvm_unreachable("missed an InitializedEntity kind?");
+}
+
+/// Make a (potentially elidable) temporary copy of the object
+/// provided by the given initializer by calling the appropriate copy
+/// constructor.
+///
+/// \param S The Sema object used for type-checking.
+///
+/// \param T The type of the temporary object, which must either be
+/// the type of the initializer expression or a superclass thereof.
+///
+/// \param Entity The entity being initialized.
+///
+/// \param CurInit The initializer expression.
+///
+/// \param IsExtraneousCopy Whether this is an "extraneous" copy that
+/// is permitted in C++03 (but not C++0x) when binding a reference to
+/// an rvalue.
+///
+/// \returns An expression that copies the initializer expression into
+/// a temporary object, or an error expression if a copy could not be
+/// created.
+static ExprResult CopyObject(Sema &S,
+                             QualType T,
+                             const InitializedEntity &Entity,
+                             ExprResult CurInit,
+                             bool IsExtraneousCopy) {
+  if (CurInit.isInvalid())
+    return CurInit;
+  // Determine which class type we're copying to.
+  Expr *CurInitExpr = (Expr *)CurInit.get();
+  CXXRecordDecl *Class = nullptr;
+  if (const RecordType *Record = T->getAs<RecordType>())
+    Class = cast<CXXRecordDecl>(Record->getDecl());
+  if (!Class)
+    return CurInit;
+
+  SourceLocation Loc = getInitializationLoc(Entity, CurInit.get());
+
+  // Make sure that the type we are copying is complete.
+  if (S.RequireCompleteType(Loc, T, diag::err_temp_copy_incomplete))
+    return CurInit;
+
+  // Perform overload resolution using the class's constructors. Per
+  // C++11 [dcl.init]p16, second bullet for class types, this initialization
+  // is direct-initialization.
+  OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
+  DeclContext::lookup_result Ctors = S.LookupConstructors(Class);
+
+  OverloadCandidateSet::iterator Best;
+  switch (ResolveConstructorOverload(
+      S, Loc, CurInitExpr, CandidateSet, T, Ctors, Best,
+      /*CopyInitializing=*/false, /*AllowExplicit=*/true,
+      /*OnlyListConstructors=*/false, /*IsListInit=*/false,
+      /*SecondStepOfCopyInit=*/true)) {
+  case OR_Success:
+    break;
+
+  case OR_No_Viable_Function:
+    CandidateSet.NoteCandidates(
+        PartialDiagnosticAt(
+            Loc, S.PDiag(IsExtraneousCopy && !S.isSFINAEContext()
+                             ? diag::ext_rvalue_to_reference_temp_copy_no_viable
+                             : diag::err_temp_copy_no_viable)
+                     << (int)Entity.getKind() << CurInitExpr->getType()
+                     << CurInitExpr->getSourceRange()),
+        S, OCD_AllCandidates, CurInitExpr);
+    if (!IsExtraneousCopy || S.isSFINAEContext())
+      return ExprError();
+    return CurInit;
+
+  case OR_Ambiguous:
+    CandidateSet.NoteCandidates(
+        PartialDiagnosticAt(Loc, S.PDiag(diag::err_temp_copy_ambiguous)
+                                     << (int)Entity.getKind()
+                                     << CurInitExpr->getType()
+                                     << CurInitExpr->getSourceRange()),
+        S, OCD_ViableCandidates, CurInitExpr);
+    return ExprError();
+
+  case OR_Deleted:
+    S.Diag(Loc, diag::err_temp_copy_deleted)
+      << (int)Entity.getKind() << CurInitExpr->getType()
+      << CurInitExpr->getSourceRange();
+    S.NoteDeletedFunction(Best->Function);
+    return ExprError();
+  }
+
+  bool HadMultipleCandidates = CandidateSet.size() > 1;
+
+  CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function);
+  SmallVector<Expr*, 8> ConstructorArgs;
+  CurInit.get(); // Ownership transferred into MultiExprArg, below.
+
+  S.CheckConstructorAccess(Loc, Constructor, Best->FoundDecl, Entity,
+                           IsExtraneousCopy);
+
+  if (IsExtraneousCopy) {
+    // If this is a totally extraneous copy for C++03 reference
+    // binding purposes, just return the original initialization
+    // expression. We don't generate an (elided) copy operation here
+    // because doing so would require us to pass down a flag to avoid
+    // infinite recursion, where each step adds another extraneous,
+    // elidable copy.
+
+    // Instantiate the default arguments of any extra parameters in
+    // the selected copy constructor, as if we were going to create a
+    // proper call to the copy constructor.
+    for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) {
+      ParmVarDecl *Parm = Constructor->getParamDecl(I);
+      if (S.RequireCompleteType(Loc, Parm->getType(),
+                                diag::err_call_incomplete_argument))
+        break;
+
+      // Build the default argument expression; we don't actually care
+      // if this succeeds or not, because this routine will complain
+      // if there was a problem.
+      S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm);
+    }
+
+    return CurInitExpr;
+  }
+
+  // Determine the arguments required to actually perform the
+  // constructor call (we might have derived-to-base conversions, or
+  // the copy constructor may have default arguments).
+  if (S.CompleteConstructorCall(Constructor, CurInitExpr, Loc, ConstructorArgs))
+    return ExprError();
+
+  // C++0x [class.copy]p32:
+  //   When certain criteria are met, an implementation is allowed to
+  //   omit the copy/move construction of a class object, even if the
+  //   copy/move constructor and/or destructor for the object have
+  //   side effects. [...]
+  //     - when a temporary class object that has not been bound to a
+  //       reference (12.2) would be copied/moved to a class object
+  //       with the same cv-unqualified type, the copy/move operation
+  //       can be omitted by constructing the temporary object
+  //       directly into the target of the omitted copy/move
+  //
+  // Note that the other three bullets are handled elsewhere. Copy
+  // elision for return statements and throw expressions are handled as part
+  // of constructor initialization, while copy elision for exception handlers
+  // is handled by the run-time.
+  //
+  // FIXME: If the function parameter is not the same type as the temporary, we
+  // should still be able to elide the copy, but we don't have a way to
+  // represent in the AST how much should be elided in this case.
+  bool Elidable =
+      CurInitExpr->isTemporaryObject(S.Context, Class) &&
+      S.Context.hasSameUnqualifiedType(
+          Best->Function->getParamDecl(0)->getType().getNonReferenceType(),
+          CurInitExpr->getType());
+
+  // Actually perform the constructor call.
+  CurInit = S.BuildCXXConstructExpr(Loc, T, Best->FoundDecl, Constructor,
+                                    Elidable,
+                                    ConstructorArgs,
+                                    HadMultipleCandidates,
+                                    /*ListInit*/ false,
+                                    /*StdInitListInit*/ false,
+                                    /*ZeroInit*/ false,
+                                    CXXConstructExpr::CK_Complete,
+                                    SourceRange());
+
+  // If we're supposed to bind temporaries, do so.
+  if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity))
+    CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
+  return CurInit;
+}
+
+/// Check whether elidable copy construction for binding a reference to
+/// a temporary would have succeeded if we were building in C++98 mode, for
+/// -Wc++98-compat.
+static void CheckCXX98CompatAccessibleCopy(Sema &S,
+                                           const InitializedEntity &Entity,
+                                           Expr *CurInitExpr) {
+  assert(S.getLangOpts().CPlusPlus11);
+
+  const RecordType *Record = CurInitExpr->getType()->getAs<RecordType>();
+  if (!Record)
+    return;
+
+  SourceLocation Loc = getInitializationLoc(Entity, CurInitExpr);
+  if (S.Diags.isIgnored(diag::warn_cxx98_compat_temp_copy, Loc))
+    return;
+
+  // Find constructors which would have been considered.
+  OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
+  DeclContext::lookup_result Ctors =
+      S.LookupConstructors(cast<CXXRecordDecl>(Record->getDecl()));
+
+  // Perform overload resolution.
+  OverloadCandidateSet::iterator Best;
+  OverloadingResult OR = ResolveConstructorOverload(
+      S, Loc, CurInitExpr, CandidateSet, CurInitExpr->getType(), Ctors, Best,
+      /*CopyInitializing=*/false, /*AllowExplicit=*/true,
+      /*OnlyListConstructors=*/false, /*IsListInit=*/false,
+      /*SecondStepOfCopyInit=*/true);
+
+  PartialDiagnostic Diag = S.PDiag(diag::warn_cxx98_compat_temp_copy)
+    << OR << (int)Entity.getKind() << CurInitExpr->getType()
+    << CurInitExpr->getSourceRange();
+
+  switch (OR) {
+  case OR_Success:
+    S.CheckConstructorAccess(Loc, cast<CXXConstructorDecl>(Best->Function),
+                             Best->FoundDecl, Entity, Diag);
+    // FIXME: Check default arguments as far as that's possible.
+    break;
+
+  case OR_No_Viable_Function:
+    CandidateSet.NoteCandidates(PartialDiagnosticAt(Loc, Diag), S,
+                                OCD_AllCandidates, CurInitExpr);
+    break;
+
+  case OR_Ambiguous:
+    CandidateSet.NoteCandidates(PartialDiagnosticAt(Loc, Diag), S,
+                                OCD_ViableCandidates, CurInitExpr);
+    break;
+
+  case OR_Deleted:
+    S.Diag(Loc, Diag);
+    S.NoteDeletedFunction(Best->Function);
+    break;
+  }
+}
+
+void InitializationSequence::PrintInitLocationNote(Sema &S,
+                                              const InitializedEntity &Entity) {
+  if (Entity.isParameterKind() && Entity.getDecl()) {
+    if (Entity.getDecl()->getLocation().isInvalid())
+      return;
+
+    if (Entity.getDecl()->getDeclName())
+      S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here)
+        << Entity.getDecl()->getDeclName();
+    else
+      S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here);
+  }
+  else if (Entity.getKind() == InitializedEntity::EK_RelatedResult &&
+           Entity.getMethodDecl())
+    S.Diag(Entity.getMethodDecl()->getLocation(),
+           diag::note_method_return_type_change)
+      << Entity.getMethodDecl()->getDeclName();
+}
+
+/// Returns true if the parameters describe a constructor initialization of
+/// an explicit temporary object, e.g. "Point(x, y)".
+static bool isExplicitTemporary(const InitializedEntity &Entity,
+                                const InitializationKind &Kind,
+                                unsigned NumArgs) {
+  switch (Entity.getKind()) {
+  case InitializedEntity::EK_Temporary:
+  case InitializedEntity::EK_CompoundLiteralInit:
+  case InitializedEntity::EK_RelatedResult:
+    break;
+  default:
+    return false;
+  }
+
+  switch (Kind.getKind()) {
+  case InitializationKind::IK_DirectList:
+    return true;
+  // FIXME: Hack to work around cast weirdness.
+  case InitializationKind::IK_Direct:
+  case InitializationKind::IK_Value:
+    return NumArgs != 1;
+  default:
+    return false;
+  }
+}
+
+static ExprResult
+PerformConstructorInitialization(Sema &S,
+                                 const InitializedEntity &Entity,
+                                 const InitializationKind &Kind,
+                                 MultiExprArg Args,
+                                 const InitializationSequence::Step& Step,
+                                 bool &ConstructorInitRequiresZeroInit,
+                                 bool IsListInitialization,
+                                 bool IsStdInitListInitialization,
+                                 SourceLocation LBraceLoc,
+                                 SourceLocation RBraceLoc) {
+  unsigned NumArgs = Args.size();
+  CXXConstructorDecl *Constructor
+    = cast<CXXConstructorDecl>(Step.Function.Function);
+  bool HadMultipleCandidates = Step.Function.HadMultipleCandidates;
+
+  // Build a call to the selected constructor.
+  SmallVector<Expr*, 8> ConstructorArgs;
+  SourceLocation Loc = (Kind.isCopyInit() && Kind.getEqualLoc().isValid())
+                         ? Kind.getEqualLoc()
+                         : Kind.getLocation();
+
+  if (Kind.getKind() == InitializationKind::IK_Default) {
+    // Force even a trivial, implicit default constructor to be
+    // semantically checked. We do this explicitly because we don't build
+    // the definition for completely trivial constructors.
+    assert(Constructor->getParent() && "No parent class for constructor.");
+    if (Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
+        Constructor->isTrivial() && !Constructor->isUsed(false))
+      S.DefineImplicitDefaultConstructor(Loc, Constructor);
+  }
+
+  ExprResult CurInit((Expr *)nullptr);
+
+  // C++ [over.match.copy]p1:
+  //   - When initializing a temporary to be bound to the first parameter
+  //     of a constructor that takes a reference to possibly cv-qualified
+  //     T as its first argument, called with a single argument in the
+  //     context of direct-initialization, explicit conversion functions
+  //     are also considered.
+  bool AllowExplicitConv =
+      Kind.AllowExplicit() && !Kind.isCopyInit() && Args.size() == 1 &&
+      hasCopyOrMoveCtorParam(S.Context,
+                             getConstructorInfo(Step.Function.FoundDecl));
+
+  // Determine the arguments required to actually perform the constructor
+  // call.
+  if (S.CompleteConstructorCall(Constructor, Args,
+                                Loc, ConstructorArgs,
+                                AllowExplicitConv,
+                                IsListInitialization))
+    return ExprError();
+
+
+  if (isExplicitTemporary(Entity, Kind, NumArgs)) {
+    // An explicitly-constructed temporary, e.g., X(1, 2).
+    if (S.DiagnoseUseOfDecl(Constructor, Loc))
+      return ExprError();
+
+    TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
+    if (!TSInfo)
+      TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc);
+    SourceRange ParenOrBraceRange =
+        (Kind.getKind() == InitializationKind::IK_DirectList)
+        ? SourceRange(LBraceLoc, RBraceLoc)
+        : Kind.getParenOrBraceRange();
+
+    if (auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(
+            Step.Function.FoundDecl.getDecl())) {
+      Constructor = S.findInheritingConstructor(Loc, Constructor, Shadow);
+      if (S.DiagnoseUseOfDecl(Constructor, Loc))
+        return ExprError();
+    }
+    S.MarkFunctionReferenced(Loc, Constructor);
+
+    CurInit = CXXTemporaryObjectExpr::Create(
+        S.Context, Constructor,
+        Entity.getType().getNonLValueExprType(S.Context), TSInfo,
+        ConstructorArgs, ParenOrBraceRange, HadMultipleCandidates,
+        IsListInitialization, IsStdInitListInitialization,
+        ConstructorInitRequiresZeroInit);
+  } else {
+    CXXConstructExpr::ConstructionKind ConstructKind =
+      CXXConstructExpr::CK_Complete;
+
+    if (Entity.getKind() == InitializedEntity::EK_Base) {
+      ConstructKind = Entity.getBaseSpecifier()->isVirtual() ?
+        CXXConstructExpr::CK_VirtualBase :
+        CXXConstructExpr::CK_NonVirtualBase;
+    } else if (Entity.getKind() == InitializedEntity::EK_Delegating) {
+      ConstructKind = CXXConstructExpr::CK_Delegating;
+    }
+
+    // Only get the parenthesis or brace range if it is a list initialization or
+    // direct construction.
+    SourceRange ParenOrBraceRange;
+    if (IsListInitialization)
+      ParenOrBraceRange = SourceRange(LBraceLoc, RBraceLoc);
+    else if (Kind.getKind() == InitializationKind::IK_Direct)
+      ParenOrBraceRange = Kind.getParenOrBraceRange();
+
+    // If the entity allows NRVO, mark the construction as elidable
+    // unconditionally.
+    if (Entity.allowsNRVO())
+      CurInit = S.BuildCXXConstructExpr(Loc, Step.Type,
+                                        Step.Function.FoundDecl,
+                                        Constructor, /*Elidable=*/true,
+                                        ConstructorArgs,
+                                        HadMultipleCandidates,
+                                        IsListInitialization,
+                                        IsStdInitListInitialization,
+                                        ConstructorInitRequiresZeroInit,
+                                        ConstructKind,
+                                        ParenOrBraceRange);
+    else
+      CurInit = S.BuildCXXConstructExpr(Loc, Step.Type,
+                                        Step.Function.FoundDecl,
+                                        Constructor,
+                                        ConstructorArgs,
+                                        HadMultipleCandidates,
+                                        IsListInitialization,
+                                        IsStdInitListInitialization,
+                                        ConstructorInitRequiresZeroInit,
+                                        ConstructKind,
+                                        ParenOrBraceRange);
+  }
+  if (CurInit.isInvalid())
+    return ExprError();
+
+  // Only check access if all of that succeeded.
+  S.CheckConstructorAccess(Loc, Constructor, Step.Function.FoundDecl, Entity);
+  if (S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc))
+    return ExprError();
+
+  if (const ArrayType *AT = S.Context.getAsArrayType(Entity.getType()))
+    if (checkDestructorReference(S.Context.getBaseElementType(AT), Loc, S))
+      return ExprError();
+
+  if (shouldBindAsTemporary(Entity))
+    CurInit = S.MaybeBindToTemporary(CurInit.get());
+
+  return CurInit;
+}
+
+namespace {
+enum LifetimeKind {
+  /// The lifetime of a temporary bound to this entity ends at the end of the
+  /// full-expression, and that's (probably) fine.
+  LK_FullExpression,
+
+  /// The lifetime of a temporary bound to this entity is extended to the
+  /// lifeitme of the entity itself.
+  LK_Extended,
+
+  /// The lifetime of a temporary bound to this entity probably ends too soon,
+  /// because the entity is allocated in a new-expression.
+  LK_New,
+
+  /// The lifetime of a temporary bound to this entity ends too soon, because
+  /// the entity is a return object.
+  LK_Return,
+
+  /// The lifetime of a temporary bound to this entity ends too soon, because
+  /// the entity is the result of a statement expression.
+  LK_StmtExprResult,
+
+  /// This is a mem-initializer: if it would extend a temporary (other than via
+  /// a default member initializer), the program is ill-formed.
+  LK_MemInitializer,
+};
+using LifetimeResult =
+    llvm::PointerIntPair<const InitializedEntity *, 3, LifetimeKind>;
+}
+
+/// Determine the declaration which an initialized entity ultimately refers to,
+/// for the purpose of lifetime-extending a temporary bound to a reference in
+/// the initialization of \p Entity.
+static LifetimeResult getEntityLifetime(
+    const InitializedEntity *Entity,
+    const InitializedEntity *InitField = nullptr) {
+  // C++11 [class.temporary]p5:
+  switch (Entity->getKind()) {
+  case InitializedEntity::EK_Variable:
+    //   The temporary [...] persists for the lifetime of the reference
+    return {Entity, LK_Extended};
+
+  case InitializedEntity::EK_Member:
+    // For subobjects, we look at the complete object.
+    if (Entity->getParent())
+      return getEntityLifetime(Entity->getParent(), Entity);
+
+    //   except:
+    // C++17 [class.base.init]p8:
+    //   A temporary expression bound to a reference member in a
+    //   mem-initializer is ill-formed.
+    // C++17 [class.base.init]p11:
+    //   A temporary expression bound to a reference member from a
+    //   default member initializer is ill-formed.
+    //
+    // The context of p11 and its example suggest that it's only the use of a
+    // default member initializer from a constructor that makes the program
+    // ill-formed, not its mere existence, and that it can even be used by
+    // aggregate initialization.
+    return {Entity, Entity->isDefaultMemberInitializer() ? LK_Extended
+                                                         : LK_MemInitializer};
+
+  case InitializedEntity::EK_Binding:
+    // Per [dcl.decomp]p3, the binding is treated as a variable of reference
+    // type.
+    return {Entity, LK_Extended};
+
+  case InitializedEntity::EK_Parameter:
+  case InitializedEntity::EK_Parameter_CF_Audited:
+    //   -- A temporary bound to a reference parameter in a function call
+    //      persists until the completion of the full-expression containing
+    //      the call.
+    return {nullptr, LK_FullExpression};
+
+  case InitializedEntity::EK_Result:
+    //   -- The lifetime of a temporary bound to the returned value in a
+    //      function return statement is not extended; the temporary is
+    //      destroyed at the end of the full-expression in the return statement.
+    return {nullptr, LK_Return};
+
+  case InitializedEntity::EK_StmtExprResult:
+    // FIXME: Should we lifetime-extend through the result of a statement
+    // expression?
+    return {nullptr, LK_StmtExprResult};
+
+  case InitializedEntity::EK_New:
+    //   -- A temporary bound to a reference in a new-initializer persists
+    //      until the completion of the full-expression containing the
+    //      new-initializer.
+    return {nullptr, LK_New};
+
+  case InitializedEntity::EK_Temporary:
+  case InitializedEntity::EK_CompoundLiteralInit:
+  case InitializedEntity::EK_RelatedResult:
+    // We don't yet know the storage duration of the surrounding temporary.
+    // Assume it's got full-expression duration for now, it will patch up our
+    // storage duration if that's not correct.
+    return {nullptr, LK_FullExpression};
+
+  case InitializedEntity::EK_ArrayElement:
+    // For subobjects, we look at the complete object.
+    return getEntityLifetime(Entity->getParent(), InitField);
+
+  case InitializedEntity::EK_Base:
+    // For subobjects, we look at the complete object.
+    if (Entity->getParent())
+      return getEntityLifetime(Entity->getParent(), InitField);
+    return {InitField, LK_MemInitializer};
+
+  case InitializedEntity::EK_Delegating:
+    // We can reach this case for aggregate initialization in a constructor:
+    //   struct A { int &&r; };
+    //   struct B : A { B() : A{0} {} };
+    // In this case, use the outermost field decl as the context.
+    return {InitField, LK_MemInitializer};
+
+  case InitializedEntity::EK_BlockElement:
+  case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
+  case InitializedEntity::EK_LambdaCapture:
+  case InitializedEntity::EK_VectorElement:
+  case InitializedEntity::EK_ComplexElement:
+    return {nullptr, LK_FullExpression};
+
+  case InitializedEntity::EK_Exception:
+    // FIXME: Can we diagnose lifetime problems with exceptions?
+    return {nullptr, LK_FullExpression};
+  }
+  llvm_unreachable("unknown entity kind");
+}
+
+namespace {
+enum ReferenceKind {
+  /// Lifetime would be extended by a reference binding to a temporary.
+  RK_ReferenceBinding,
+  /// Lifetime would be extended by a std::initializer_list object binding to
+  /// its backing array.
+  RK_StdInitializerList,
+};
+
+/// A temporary or local variable. This will be one of:
+///  * A MaterializeTemporaryExpr.
+///  * A DeclRefExpr whose declaration is a local.
+///  * An AddrLabelExpr.
+///  * A BlockExpr for a block with captures.
+using Local = Expr*;
+
+/// Expressions we stepped over when looking for the local state. Any steps
+/// that would inhibit lifetime extension or take us out of subexpressions of
+/// the initializer are included.
+struct IndirectLocalPathEntry {
+  enum EntryKind {
+    DefaultInit,
+    AddressOf,
+    VarInit,
+    LValToRVal,
+    LifetimeBoundCall,
+  } Kind;
+  Expr *E;
+  const Decl *D = nullptr;
+  IndirectLocalPathEntry() {}
+  IndirectLocalPathEntry(EntryKind K, Expr *E) : Kind(K), E(E) {}
+  IndirectLocalPathEntry(EntryKind K, Expr *E, const Decl *D)
+      : Kind(K), E(E), D(D) {}
+};
+
+using IndirectLocalPath = llvm::SmallVectorImpl<IndirectLocalPathEntry>;
+
+struct RevertToOldSizeRAII {
+  IndirectLocalPath &Path;
+  unsigned OldSize = Path.size();
+  RevertToOldSizeRAII(IndirectLocalPath &Path) : Path(Path) {}
+  ~RevertToOldSizeRAII() { Path.resize(OldSize); }
+};
+
+using LocalVisitor = llvm::function_ref<bool(IndirectLocalPath &Path, Local L,
+                                             ReferenceKind RK)>;
+}
+
+static bool isVarOnPath(IndirectLocalPath &Path, VarDecl *VD) {
+  for (auto E : Path)
+    if (E.Kind == IndirectLocalPathEntry::VarInit && E.D == VD)
+      return true;
+  return false;
+}
+
+static bool pathContainsInit(IndirectLocalPath &Path) {
+  return llvm::any_of(Path, [=](IndirectLocalPathEntry E) {
+    return E.Kind == IndirectLocalPathEntry::DefaultInit ||
+           E.Kind == IndirectLocalPathEntry::VarInit;
+  });
+}
+
+static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
+                                             Expr *Init, LocalVisitor Visit,
+                                             bool RevisitSubinits);
+
+static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
+                                                  Expr *Init, ReferenceKind RK,
+                                                  LocalVisitor Visit);
+
+static bool implicitObjectParamIsLifetimeBound(const FunctionDecl *FD) {
+  const TypeSourceInfo *TSI = FD->getTypeSourceInfo();
+  if (!TSI)
+    return false;
+  // Don't declare this variable in the second operand of the for-statement;
+  // GCC miscompiles that by ending its lifetime before evaluating the
+  // third operand. See gcc.gnu.org/PR86769.
+  AttributedTypeLoc ATL;
+  for (TypeLoc TL = TSI->getTypeLoc();
+       (ATL = TL.getAsAdjusted<AttributedTypeLoc>());
+       TL = ATL.getModifiedLoc()) {
+    if (ATL.getAttrAs<LifetimeBoundAttr>())
+      return true;
+  }
+  return false;
+}
+
+static void visitLifetimeBoundArguments(IndirectLocalPath &Path, Expr *Call,
+                                        LocalVisitor Visit) {
+  const FunctionDecl *Callee;
+  ArrayRef<Expr*> Args;
+
+  if (auto *CE = dyn_cast<CallExpr>(Call)) {
+    Callee = CE->getDirectCallee();
+    Args = llvm::makeArrayRef(CE->getArgs(), CE->getNumArgs());
+  } else {
+    auto *CCE = cast<CXXConstructExpr>(Call);
+    Callee = CCE->getConstructor();
+    Args = llvm::makeArrayRef(CCE->getArgs(), CCE->getNumArgs());
+  }
+  if (!Callee)
+    return;
+
+  Expr *ObjectArg = nullptr;
+  if (isa<CXXOperatorCallExpr>(Call) && Callee->isCXXInstanceMember()) {
+    ObjectArg = Args[0];
+    Args = Args.slice(1);
+  } else if (auto *MCE = dyn_cast<CXXMemberCallExpr>(Call)) {
+    ObjectArg = MCE->getImplicitObjectArgument();
+  }
+
+  auto VisitLifetimeBoundArg = [&](const Decl *D, Expr *Arg) {
+    Path.push_back({IndirectLocalPathEntry::LifetimeBoundCall, Arg, D});
+    if (Arg->isGLValue())
+      visitLocalsRetainedByReferenceBinding(Path, Arg, RK_ReferenceBinding,
+                                            Visit);
+    else
+      visitLocalsRetainedByInitializer(Path, Arg, Visit, true);
+    Path.pop_back();
+  };
+
+  if (ObjectArg && implicitObjectParamIsLifetimeBound(Callee))
+    VisitLifetimeBoundArg(Callee, ObjectArg);
+
+  for (unsigned I = 0,
+                N = std::min<unsigned>(Callee->getNumParams(), Args.size());
+       I != N; ++I) {
+    if (Callee->getParamDecl(I)->hasAttr<LifetimeBoundAttr>())
+      VisitLifetimeBoundArg(Callee->getParamDecl(I), Args[I]);
+  }
+}
+
+/// Visit the locals that would be reachable through a reference bound to the
+/// glvalue expression \c Init.
+static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
+                                                  Expr *Init, ReferenceKind RK,
+                                                  LocalVisitor Visit) {
+  RevertToOldSizeRAII RAII(Path);
+
+  // Walk past any constructs which we can lifetime-extend across.
+  Expr *Old;
+  do {
+    Old = Init;
+
+    if (auto *FE = dyn_cast<FullExpr>(Init))
+      Init = FE->getSubExpr();
+
+    if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
+      // If this is just redundant braces around an initializer, step over it.
+      if (ILE->isTransparent())
+        Init = ILE->getInit(0);
+    }
+
+    // Step over any subobject adjustments; we may have a materialized
+    // temporary inside them.
+    Init = const_cast<Expr *>(Init->skipRValueSubobjectAdjustments());
+
+    // Per current approach for DR1376, look through casts to reference type
+    // when performing lifetime extension.
+    if (CastExpr *CE = dyn_cast<CastExpr>(Init))
+      if (CE->getSubExpr()->isGLValue())
+        Init = CE->getSubExpr();
+
+    // Per the current approach for DR1299, look through array element access
+    // on array glvalues when performing lifetime extension.
+    if (auto *ASE = dyn_cast<ArraySubscriptExpr>(Init)) {
+      Init = ASE->getBase();
+      auto *ICE = dyn_cast<ImplicitCastExpr>(Init);
+      if (ICE && ICE->getCastKind() == CK_ArrayToPointerDecay)
+        Init = ICE->getSubExpr();
+      else
+        // We can't lifetime extend through this but we might still find some
+        // retained temporaries.
+        return visitLocalsRetainedByInitializer(Path, Init, Visit, true);
+    }
+
+    // Step into CXXDefaultInitExprs so we can diagnose cases where a
+    // constructor inherits one as an implicit mem-initializer.
+    if (auto *DIE = dyn_cast<CXXDefaultInitExpr>(Init)) {
+      Path.push_back(
+          {IndirectLocalPathEntry::DefaultInit, DIE, DIE->getField()});
+      Init = DIE->getExpr();
+    }
+  } while (Init != Old);
+
+  if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Init)) {
+    if (Visit(Path, Local(MTE), RK))
+      visitLocalsRetainedByInitializer(Path, MTE->GetTemporaryExpr(), Visit,
+                                       true);
+  }
+
+  if (isa<CallExpr>(Init))
+    return visitLifetimeBoundArguments(Path, Init, Visit);
+
+  switch (Init->getStmtClass()) {
+  case Stmt::DeclRefExprClass: {
+    // If we find the name of a local non-reference parameter, we could have a
+    // lifetime problem.
+    auto *DRE = cast<DeclRefExpr>(Init);
+    auto *VD = dyn_cast<VarDecl>(DRE->getDecl());
+    if (VD && VD->hasLocalStorage() &&
+        !DRE->refersToEnclosingVariableOrCapture()) {
+      if (!VD->getType()->isReferenceType()) {
+        Visit(Path, Local(DRE), RK);
+      } else if (isa<ParmVarDecl>(DRE->getDecl())) {
+        // The lifetime of a reference parameter is unknown; assume it's OK
+        // for now.
+        break;
+      } else if (VD->getInit() && !isVarOnPath(Path, VD)) {
+        Path.push_back({IndirectLocalPathEntry::VarInit, DRE, VD});
+        visitLocalsRetainedByReferenceBinding(Path, VD->getInit(),
+                                              RK_ReferenceBinding, Visit);
+      }
+    }
+    break;
+  }
+
+  case Stmt::UnaryOperatorClass: {
+    // The only unary operator that make sense to handle here
+    // is Deref.  All others don't resolve to a "name."  This includes
+    // handling all sorts of rvalues passed to a unary operator.
+    const UnaryOperator *U = cast<UnaryOperator>(Init);
+    if (U->getOpcode() == UO_Deref)
+      visitLocalsRetainedByInitializer(Path, U->getSubExpr(), Visit, true);
+    break;
+  }
+
+  case Stmt::OMPArraySectionExprClass: {
+    visitLocalsRetainedByInitializer(
+        Path, cast<OMPArraySectionExpr>(Init)->getBase(), Visit, true);
+    break;
+  }
+
+  case Stmt::ConditionalOperatorClass:
+  case Stmt::BinaryConditionalOperatorClass: {
+    auto *C = cast<AbstractConditionalOperator>(Init);
+    if (!C->getTrueExpr()->getType()->isVoidType())
+      visitLocalsRetainedByReferenceBinding(Path, C->getTrueExpr(), RK, Visit);
+    if (!C->getFalseExpr()->getType()->isVoidType())
+      visitLocalsRetainedByReferenceBinding(Path, C->getFalseExpr(), RK, Visit);
+    break;
+  }
+
+  // FIXME: Visit the left-hand side of an -> or ->*.
+
+  default:
+    break;
+  }
+}
+
+/// Visit the locals that would be reachable through an object initialized by
+/// the prvalue expression \c Init.
+static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
+                                             Expr *Init, LocalVisitor Visit,
+                                             bool RevisitSubinits) {
+  RevertToOldSizeRAII RAII(Path);
+
+  Expr *Old;
+  do {
+    Old = Init;
+
+    // Step into CXXDefaultInitExprs so we can diagnose cases where a
+    // constructor inherits one as an implicit mem-initializer.
+    if (auto *DIE = dyn_cast<CXXDefaultInitExpr>(Init)) {
+      Path.push_back({IndirectLocalPathEntry::DefaultInit, DIE, DIE->getField()});
+      Init = DIE->getExpr();
+    }
+
+    if (auto *FE = dyn_cast<FullExpr>(Init))
+      Init = FE->getSubExpr();
+
+    // Dig out the expression which constructs the extended temporary.
+    Init = const_cast<Expr *>(Init->skipRValueSubobjectAdjustments());
+
+    if (CXXBindTemporaryExpr *BTE = dyn_cast<CXXBindTemporaryExpr>(Init))
+      Init = BTE->getSubExpr();
+
+    Init = Init->IgnoreParens();
+
+    // Step over value-preserving rvalue casts.
+    if (auto *CE = dyn_cast<CastExpr>(Init)) {
+      switch (CE->getCastKind()) {
+      case CK_LValueToRValue:
+        // If we can match the lvalue to a const object, we can look at its
+        // initializer.
+        Path.push_back({IndirectLocalPathEntry::LValToRVal, CE});
+        return visitLocalsRetainedByReferenceBinding(
+            Path, Init, RK_ReferenceBinding,
+            [&](IndirectLocalPath &Path, Local L, ReferenceKind RK) -> bool {
+          if (auto *DRE = dyn_cast<DeclRefExpr>(L)) {
+            auto *VD = dyn_cast<VarDecl>(DRE->getDecl());
+            if (VD && VD->getType().isConstQualified() && VD->getInit() &&
+                !isVarOnPath(Path, VD)) {
+              Path.push_back({IndirectLocalPathEntry::VarInit, DRE, VD});
+              visitLocalsRetainedByInitializer(Path, VD->getInit(), Visit, true);
+            }
+          } else if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(L)) {
+            if (MTE->getType().isConstQualified())
+              visitLocalsRetainedByInitializer(Path, MTE->GetTemporaryExpr(),
+                                               Visit, true);
+          }
+          return false;
+        });
+
+        // We assume that objects can be retained by pointers cast to integers,
+        // but not if the integer is cast to floating-point type or to _Complex.
+        // We assume that casts to 'bool' do not preserve enough information to
+        // retain a local object.
+      case CK_NoOp:
+      case CK_BitCast:
+      case CK_BaseToDerived:
+      case CK_DerivedToBase:
+      case CK_UncheckedDerivedToBase:
+      case CK_Dynamic:
+      case CK_ToUnion:
+      case CK_UserDefinedConversion:
+      case CK_ConstructorConversion:
+      case CK_IntegralToPointer:
+      case CK_PointerToIntegral:
+      case CK_VectorSplat:
+      case CK_IntegralCast:
+      case CK_CPointerToObjCPointerCast:
+      case CK_BlockPointerToObjCPointerCast:
+      case CK_AnyPointerToBlockPointerCast:
+      case CK_AddressSpaceConversion:
+        break;
+
+      case CK_ArrayToPointerDecay:
+        // Model array-to-pointer decay as taking the address of the array
+        // lvalue.
+        Path.push_back({IndirectLocalPathEntry::AddressOf, CE});
+        return visitLocalsRetainedByReferenceBinding(Path, CE->getSubExpr(),
+                                                     RK_ReferenceBinding, Visit);
+
+      default:
+        return;
+      }
+
+      Init = CE->getSubExpr();
+    }
+  } while (Old != Init);
+
+  // C++17 [dcl.init.list]p6:
+  //   initializing an initializer_list object from the array extends the
+  //   lifetime of the array exactly like binding a reference to a temporary.
+  if (auto *ILE = dyn_cast<CXXStdInitializerListExpr>(Init))
+    return visitLocalsRetainedByReferenceBinding(Path, ILE->getSubExpr(),
+                                                 RK_StdInitializerList, Visit);
+
+  if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
+    // We already visited the elements of this initializer list while
+    // performing the initialization. Don't visit them again unless we've
+    // changed the lifetime of the initialized entity.
+    if (!RevisitSubinits)
+      return;
+
+    if (ILE->isTransparent())
+      return visitLocalsRetainedByInitializer(Path, ILE->getInit(0), Visit,
+                                              RevisitSubinits);
+
+    if (ILE->getType()->isArrayType()) {
+      for (unsigned I = 0, N = ILE->getNumInits(); I != N; ++I)
+        visitLocalsRetainedByInitializer(Path, ILE->getInit(I), Visit,
+                                         RevisitSubinits);
+      return;
+    }
+
+    if (CXXRecordDecl *RD = ILE->getType()->getAsCXXRecordDecl()) {
+      assert(RD->isAggregate() && "aggregate init on non-aggregate");
+
+      // If we lifetime-extend a braced initializer which is initializing an
+      // aggregate, and that aggregate contains reference members which are
+      // bound to temporaries, those temporaries are also lifetime-extended.
+      if (RD->isUnion() && ILE->getInitializedFieldInUnion() &&
+          ILE->getInitializedFieldInUnion()->getType()->isReferenceType())
+        visitLocalsRetainedByReferenceBinding(Path, ILE->getInit(0),
+                                              RK_ReferenceBinding, Visit);
+      else {
+        unsigned Index = 0;
+        for (; Index < RD->getNumBases() && Index < ILE->getNumInits(); ++Index)
+          visitLocalsRetainedByInitializer(Path, ILE->getInit(Index), Visit,
+                                           RevisitSubinits);
+        for (const auto *I : RD->fields()) {
+          if (Index >= ILE->getNumInits())
+            break;
+          if (I->isUnnamedBitfield())
+            continue;
+          Expr *SubInit = ILE->getInit(Index);
+          if (I->getType()->isReferenceType())
+            visitLocalsRetainedByReferenceBinding(Path, SubInit,
+                                                  RK_ReferenceBinding, Visit);
+          else
+            // This might be either aggregate-initialization of a member or
+            // initialization of a std::initializer_list object. Regardless,
+            // we should recursively lifetime-extend that initializer.
+            visitLocalsRetainedByInitializer(Path, SubInit, Visit,
+                                             RevisitSubinits);
+          ++Index;
+        }
+      }
+    }
+    return;
+  }
+
+  // The lifetime of an init-capture is that of the closure object constructed
+  // by a lambda-expression.
+  if (auto *LE = dyn_cast<LambdaExpr>(Init)) {
+    for (Expr *E : LE->capture_inits()) {
+      if (!E)
+        continue;
+      if (E->isGLValue())
+        visitLocalsRetainedByReferenceBinding(Path, E, RK_ReferenceBinding,
+                                              Visit);
+      else
+        visitLocalsRetainedByInitializer(Path, E, Visit, true);
+    }
+  }
+
+  if (isa<CallExpr>(Init) || isa<CXXConstructExpr>(Init))
+    return visitLifetimeBoundArguments(Path, Init, Visit);
+
+  switch (Init->getStmtClass()) {
+  case Stmt::UnaryOperatorClass: {
+    auto *UO = cast<UnaryOperator>(Init);
+    // If the initializer is the address of a local, we could have a lifetime
+    // problem.
+    if (UO->getOpcode() == UO_AddrOf) {
+      // If this is &rvalue, then it's ill-formed and we have already diagnosed
+      // it. Don't produce a redundant warning about the lifetime of the
+      // temporary.
+      if (isa<MaterializeTemporaryExpr>(UO->getSubExpr()))
+        return;
+
+      Path.push_back({IndirectLocalPathEntry::AddressOf, UO});
+      visitLocalsRetainedByReferenceBinding(Path, UO->getSubExpr(),
+                                            RK_ReferenceBinding, Visit);
+    }
+    break;
+  }
+
+  case Stmt::BinaryOperatorClass: {
+    // Handle pointer arithmetic.
+    auto *BO = cast<BinaryOperator>(Init);
+    BinaryOperatorKind BOK = BO->getOpcode();
+    if (!BO->getType()->isPointerType() || (BOK != BO_Add && BOK != BO_Sub))
+      break;
+
+    if (BO->getLHS()->getType()->isPointerType())
+      visitLocalsRetainedByInitializer(Path, BO->getLHS(), Visit, true);
+    else if (BO->getRHS()->getType()->isPointerType())
+      visitLocalsRetainedByInitializer(Path, BO->getRHS(), Visit, true);
+    break;
+  }
+
+  case Stmt::ConditionalOperatorClass:
+  case Stmt::BinaryConditionalOperatorClass: {
+    auto *C = cast<AbstractConditionalOperator>(Init);
+    // In C++, we can have a throw-expression operand, which has 'void' type
+    // and isn't interesting from a lifetime perspective.
+    if (!C->getTrueExpr()->getType()->isVoidType())
+      visitLocalsRetainedByInitializer(Path, C->getTrueExpr(), Visit, true);
+    if (!C->getFalseExpr()->getType()->isVoidType())
+      visitLocalsRetainedByInitializer(Path, C->getFalseExpr(), Visit, true);
+    break;
+  }
+
+  case Stmt::BlockExprClass:
+    if (cast<BlockExpr>(Init)->getBlockDecl()->hasCaptures()) {
+      // This is a local block, whose lifetime is that of the function.
+      Visit(Path, Local(cast<BlockExpr>(Init)), RK_ReferenceBinding);
+    }
+    break;
+
+  case Stmt::AddrLabelExprClass:
+    // We want to warn if the address of a label would escape the function.
+    Visit(Path, Local(cast<AddrLabelExpr>(Init)), RK_ReferenceBinding);
+    break;
+
+  default:
+    break;
+  }
+}
+
+/// Determine whether this is an indirect path to a temporary that we are
+/// supposed to lifetime-extend along (but don't).
+static bool shouldLifetimeExtendThroughPath(const IndirectLocalPath &Path) {
+  for (auto Elem : Path) {
+    if (Elem.Kind != IndirectLocalPathEntry::DefaultInit)
+      return false;
+  }
+  return true;
+}
+
+/// Find the range for the first interesting entry in the path at or after I.
+static SourceRange nextPathEntryRange(const IndirectLocalPath &Path, unsigned I,
+                                      Expr *E) {
+  for (unsigned N = Path.size(); I != N; ++I) {
+    switch (Path[I].Kind) {
+    case IndirectLocalPathEntry::AddressOf:
+    case IndirectLocalPathEntry::LValToRVal:
+    case IndirectLocalPathEntry::LifetimeBoundCall:
+      // These exist primarily to mark the path as not permitting or
+      // supporting lifetime extension.
+      break;
+
+    case IndirectLocalPathEntry::DefaultInit:
+    case IndirectLocalPathEntry::VarInit:
+      return Path[I].E->getSourceRange();
+    }
+  }
+  return E->getSourceRange();
+}
+
+void Sema::checkInitializerLifetime(const InitializedEntity &Entity,
+                                    Expr *Init) {
+  LifetimeResult LR = getEntityLifetime(&Entity);
+  LifetimeKind LK = LR.getInt();
+  const InitializedEntity *ExtendingEntity = LR.getPointer();
+
+  // If this entity doesn't have an interesting lifetime, don't bother looking
+  // for temporaries within its initializer.
+  if (LK == LK_FullExpression)
+    return;
+
+  auto TemporaryVisitor = [&](IndirectLocalPath &Path, Local L,
+                              ReferenceKind RK) -> bool {
+    SourceRange DiagRange = nextPathEntryRange(Path, 0, L);
+    SourceLocation DiagLoc = DiagRange.getBegin();
+
+    switch (LK) {
+    case LK_FullExpression:
+      llvm_unreachable("already handled this");
+
+    case LK_Extended: {
+      auto *MTE = dyn_cast<MaterializeTemporaryExpr>(L);
+      if (!MTE) {
+        // The initialized entity has lifetime beyond the full-expression,
+        // and the local entity does too, so don't warn.
+        //
+        // FIXME: We should consider warning if a static / thread storage
+        // duration variable retains an automatic storage duration local.
+        return false;
+      }
+
+      // Lifetime-extend the temporary.
+      if (Path.empty()) {
+        // Update the storage duration of the materialized temporary.
+        // FIXME: Rebuild the expression instead of mutating it.
+        MTE->setExtendingDecl(ExtendingEntity->getDecl(),
+                              ExtendingEntity->allocateManglingNumber());
+        // Also visit the temporaries lifetime-extended by this initializer.
+        return true;
+      }
+
+      if (shouldLifetimeExtendThroughPath(Path)) {
+        // We're supposed to lifetime-extend the temporary along this path (per
+        // the resolution of DR1815), but we don't support that yet.
+        //
+        // FIXME: Properly handle this situation. Perhaps the easiest approach
+        // would be to clone the initializer expression on each use that would
+        // lifetime extend its temporaries.
+        Diag(DiagLoc, diag::warn_unsupported_lifetime_extension)
+            << RK << DiagRange;
+      } else {
+        // If the path goes through the initialization of a variable or field,
+        // it can't possibly reach a temporary created in this full-expression.
+        // We will have already diagnosed any problems with the initializer.
+        if (pathContainsInit(Path))
+          return false;
+
+        Diag(DiagLoc, diag::warn_dangling_variable)
+            << RK << !Entity.getParent()
+            << ExtendingEntity->getDecl()->isImplicit()
+            << ExtendingEntity->getDecl() << Init->isGLValue() << DiagRange;
+      }
+      break;
+    }
+
+    case LK_MemInitializer: {
+      if (isa<MaterializeTemporaryExpr>(L)) {
+        // Under C++ DR1696, if a mem-initializer (or a default member
+        // initializer used by the absence of one) would lifetime-extend a
+        // temporary, the program is ill-formed.
+        if (auto *ExtendingDecl =
+                ExtendingEntity ? ExtendingEntity->getDecl() : nullptr) {
+          bool IsSubobjectMember = ExtendingEntity != &Entity;
+          Diag(DiagLoc, shouldLifetimeExtendThroughPath(Path)
+                            ? diag::err_dangling_member
+                            : diag::warn_dangling_member)
+              << ExtendingDecl << IsSubobjectMember << RK << DiagRange;
+          // Don't bother adding a note pointing to the field if we're inside
+          // its default member initializer; our primary diagnostic points to
+          // the same place in that case.
+          if (Path.empty() ||
+              Path.back().Kind != IndirectLocalPathEntry::DefaultInit) {
+            Diag(ExtendingDecl->getLocation(),
+                 diag::note_lifetime_extending_member_declared_here)
+                << RK << IsSubobjectMember;
+          }
+        } else {
+          // We have a mem-initializer but no particular field within it; this
+          // is either a base class or a delegating initializer directly
+          // initializing the base-class from something that doesn't live long
+          // enough.
+          //
+          // FIXME: Warn on this.
+          return false;
+        }
+      } else {
+        // Paths via a default initializer can only occur during error recovery
+        // (there's no other way that a default initializer can refer to a
+        // local). Don't produce a bogus warning on those cases.
+        if (pathContainsInit(Path))
+          return false;
+
+        auto *DRE = dyn_cast<DeclRefExpr>(L);
+        auto *VD = DRE ? dyn_cast<VarDecl>(DRE->getDecl()) : nullptr;
+        if (!VD) {
+          // A member was initialized to a local block.
+          // FIXME: Warn on this.
+          return false;
+        }
+
+        if (auto *Member =
+                ExtendingEntity ? ExtendingEntity->getDecl() : nullptr) {
+          bool IsPointer = Member->getType()->isAnyPointerType();
+          Diag(DiagLoc, IsPointer ? diag::warn_init_ptr_member_to_parameter_addr
+                                  : diag::warn_bind_ref_member_to_parameter)
+              << Member << VD << isa<ParmVarDecl>(VD) << DiagRange;
+          Diag(Member->getLocation(),
+               diag::note_ref_or_ptr_member_declared_here)
+              << (unsigned)IsPointer;
+        }
+      }
+      break;
+    }
+
+    case LK_New:
+      if (isa<MaterializeTemporaryExpr>(L)) {
+        Diag(DiagLoc, RK == RK_ReferenceBinding
+                          ? diag::warn_new_dangling_reference
+                          : diag::warn_new_dangling_initializer_list)
+            << !Entity.getParent() << DiagRange;
+      } else {
+        // We can't determine if the allocation outlives the local declaration.
+        return false;
+      }
+      break;
+
+    case LK_Return:
+    case LK_StmtExprResult:
+      if (auto *DRE = dyn_cast<DeclRefExpr>(L)) {
+        // We can't determine if the local variable outlives the statement
+        // expression.
+        if (LK == LK_StmtExprResult)
+          return false;
+        Diag(DiagLoc, diag::warn_ret_stack_addr_ref)
+            << Entity.getType()->isReferenceType() << DRE->getDecl()
+            << isa<ParmVarDecl>(DRE->getDecl()) << DiagRange;
+      } else if (isa<BlockExpr>(L)) {
+        Diag(DiagLoc, diag::err_ret_local_block) << DiagRange;
+      } else if (isa<AddrLabelExpr>(L)) {
+        // Don't warn when returning a label from a statement expression.
+        // Leaving the scope doesn't end its lifetime.
+        if (LK == LK_StmtExprResult)
+          return false;
+        Diag(DiagLoc, diag::warn_ret_addr_label) << DiagRange;
+      } else {
+        Diag(DiagLoc, diag::warn_ret_local_temp_addr_ref)
+         << Entity.getType()->isReferenceType() << DiagRange;
+      }
+      break;
+    }
+
+    for (unsigned I = 0; I != Path.size(); ++I) {
+      auto Elem = Path[I];
+
+      switch (Elem.Kind) {
+      case IndirectLocalPathEntry::AddressOf:
+      case IndirectLocalPathEntry::LValToRVal:
+        // These exist primarily to mark the path as not permitting or
+        // supporting lifetime extension.
+        break;
+
+      case IndirectLocalPathEntry::LifetimeBoundCall:
+        // FIXME: Consider adding a note for this.
+        break;
+
+      case IndirectLocalPathEntry::DefaultInit: {
+        auto *FD = cast<FieldDecl>(Elem.D);
+        Diag(FD->getLocation(), diag::note_init_with_default_member_initalizer)
+            << FD << nextPathEntryRange(Path, I + 1, L);
+        break;
+      }
+
+      case IndirectLocalPathEntry::VarInit:
+        const VarDecl *VD = cast<VarDecl>(Elem.D);
+        Diag(VD->getLocation(), diag::note_local_var_initializer)
+            << VD->getType()->isReferenceType()
+            << VD->isImplicit() << VD->getDeclName()
+            << nextPathEntryRange(Path, I + 1, L);
+        break;
+      }
+    }
+
+    // We didn't lifetime-extend, so don't go any further; we don't need more
+    // warnings or errors on inner temporaries within this one's initializer.
+    return false;
+  };
+
+  llvm::SmallVector<IndirectLocalPathEntry, 8> Path;
+  if (Init->isGLValue())
+    visitLocalsRetainedByReferenceBinding(Path, Init, RK_ReferenceBinding,
+                                          TemporaryVisitor);
+  else
+    visitLocalsRetainedByInitializer(Path, Init, TemporaryVisitor, false);
+}
+
+static void DiagnoseNarrowingInInitList(Sema &S,
+                                        const ImplicitConversionSequence &ICS,
+                                        QualType PreNarrowingType,
+                                        QualType EntityType,
+                                        const Expr *PostInit);
+
+/// Provide warnings when std::move is used on construction.
+static void CheckMoveOnConstruction(Sema &S, const Expr *InitExpr,
+                                    bool IsReturnStmt) {
+  if (!InitExpr)
+    return;
+
+  if (S.inTemplateInstantiation())
+    return;
+
+  QualType DestType = InitExpr->getType();
+  if (!DestType->isRecordType())
+    return;
+
+  unsigned DiagID = 0;
+  if (IsReturnStmt) {
+    const CXXConstructExpr *CCE =
+        dyn_cast<CXXConstructExpr>(InitExpr->IgnoreParens());
+    if (!CCE || CCE->getNumArgs() != 1)
+      return;
+
+    if (!CCE->getConstructor()->isCopyOrMoveConstructor())
+      return;
+
+    InitExpr = CCE->getArg(0)->IgnoreImpCasts();
+  }
+
+  // Find the std::move call and get the argument.
+  const CallExpr *CE = dyn_cast<CallExpr>(InitExpr->IgnoreParens());
+  if (!CE || !CE->isCallToStdMove())
+    return;
+
+  const Expr *Arg = CE->getArg(0)->IgnoreImplicit();
+
+  if (IsReturnStmt) {
+    const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg->IgnoreParenImpCasts());
+    if (!DRE || DRE->refersToEnclosingVariableOrCapture())
+      return;
+
+    const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl());
+    if (!VD || !VD->hasLocalStorage())
+      return;
+
+    // __block variables are not moved implicitly.
+    if (VD->hasAttr<BlocksAttr>())
+      return;
+
+    QualType SourceType = VD->getType();
+    if (!SourceType->isRecordType())
+      return;
+
+    if (!S.Context.hasSameUnqualifiedType(DestType, SourceType)) {
+      return;
+    }
+
+    // If we're returning a function parameter, copy elision
+    // is not possible.
+    if (isa<ParmVarDecl>(VD))
+      DiagID = diag::warn_redundant_move_on_return;
+    else
+      DiagID = diag::warn_pessimizing_move_on_return;
+  } else {
+    DiagID = diag::warn_pessimizing_move_on_initialization;
+    const Expr *ArgStripped = Arg->IgnoreImplicit()->IgnoreParens();
+    if (!ArgStripped->isRValue() || !ArgStripped->getType()->isRecordType())
+      return;
+  }
+
+  S.Diag(CE->getBeginLoc(), DiagID);
+
+  // Get all the locations for a fix-it.  Don't emit the fix-it if any location
+  // is within a macro.
+  SourceLocation CallBegin = CE->getCallee()->getBeginLoc();
+  if (CallBegin.isMacroID())
+    return;
+  SourceLocation RParen = CE->getRParenLoc();
+  if (RParen.isMacroID())
+    return;
+  SourceLocation LParen;
+  SourceLocation ArgLoc = Arg->getBeginLoc();
+
+  // Special testing for the argument location.  Since the fix-it needs the
+  // location right before the argument, the argument location can be in a
+  // macro only if it is at the beginning of the macro.
+  while (ArgLoc.isMacroID() &&
+         S.getSourceManager().isAtStartOfImmediateMacroExpansion(ArgLoc)) {
+    ArgLoc = S.getSourceManager().getImmediateExpansionRange(ArgLoc).getBegin();
+  }
+
+  if (LParen.isMacroID())
+    return;
+
+  LParen = ArgLoc.getLocWithOffset(-1);
+
+  S.Diag(CE->getBeginLoc(), diag::note_remove_move)
+      << FixItHint::CreateRemoval(SourceRange(CallBegin, LParen))
+      << FixItHint::CreateRemoval(SourceRange(RParen, RParen));
+}
+
+static void CheckForNullPointerDereference(Sema &S, const Expr *E) {
+  // Check to see if we are dereferencing a null pointer.  If so, this is
+  // undefined behavior, so warn about it.  This only handles the pattern
+  // "*null", which is a very syntactic check.
+  if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts()))
+    if (UO->getOpcode() == UO_Deref &&
+        UO->getSubExpr()->IgnoreParenCasts()->
+        isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull)) {
+    S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
+                          S.PDiag(diag::warn_binding_null_to_reference)
+                            << UO->getSubExpr()->getSourceRange());
+  }
+}
+
+MaterializeTemporaryExpr *
+Sema::CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary,
+                                     bool BoundToLvalueReference) {
+  auto MTE = new (Context)
+      MaterializeTemporaryExpr(T, Temporary, BoundToLvalueReference);
+
+  // Order an ExprWithCleanups for lifetime marks.
+  //
+  // TODO: It'll be good to have a single place to check the access of the
+  // destructor and generate ExprWithCleanups for various uses. Currently these
+  // are done in both CreateMaterializeTemporaryExpr and MaybeBindToTemporary,
+  // but there may be a chance to merge them.
+  Cleanup.setExprNeedsCleanups(false);
+  return MTE;
+}
+
+ExprResult Sema::TemporaryMaterializationConversion(Expr *E) {
+  // In C++98, we don't want to implicitly create an xvalue.
+  // FIXME: This means that AST consumers need to deal with "prvalues" that
+  // denote materialized temporaries. Maybe we should add another ValueKind
+  // for "xvalue pretending to be a prvalue" for C++98 support.
+  if (!E->isRValue() || !getLangOpts().CPlusPlus11)
+    return E;
+
+  // C++1z [conv.rval]/1: T shall be a complete type.
+  // FIXME: Does this ever matter (can we form a prvalue of incomplete type)?
+  // If so, we should check for a non-abstract class type here too.
+  QualType T = E->getType();
+  if (RequireCompleteType(E->getExprLoc(), T, diag::err_incomplete_type))
+    return ExprError();
+
+  return CreateMaterializeTemporaryExpr(E->getType(), E, false);
+}
+
+ExprResult Sema::PerformQualificationConversion(Expr *E, QualType Ty,
+                                                ExprValueKind VK,
+                                                CheckedConversionKind CCK) {
+
+  CastKind CK = CK_NoOp;
+
+  if (VK == VK_RValue) {
+    auto PointeeTy = Ty->getPointeeType();
+    auto ExprPointeeTy = E->getType()->getPointeeType();
+    if (!PointeeTy.isNull() &&
+        PointeeTy.getAddressSpace() != ExprPointeeTy.getAddressSpace())
+      CK = CK_AddressSpaceConversion;
+  } else if (Ty.getAddressSpace() != E->getType().getAddressSpace()) {
+    CK = CK_AddressSpaceConversion;
+  }
+
+  return ImpCastExprToType(E, Ty, CK, VK, /*BasePath=*/nullptr, CCK);
+}
+
+ExprResult InitializationSequence::Perform(Sema &S,
+                                           const InitializedEntity &Entity,
+                                           const InitializationKind &Kind,
+                                           MultiExprArg Args,
+                                           QualType *ResultType) {
+  if (Failed()) {
+    Diagnose(S, Entity, Kind, Args);
+    return ExprError();
+  }
+  if (!ZeroInitializationFixit.empty()) {
+    unsigned DiagID = diag::err_default_init_const;
+    if (Decl *D = Entity.getDecl())
+      if (S.getLangOpts().MSVCCompat && D->hasAttr<SelectAnyAttr>())
+        DiagID = diag::ext_default_init_const;
+
+    // The initialization would have succeeded with this fixit. Since the fixit
+    // is on the error, we need to build a valid AST in this case, so this isn't
+    // handled in the Failed() branch above.
+    QualType DestType = Entity.getType();
+    S.Diag(Kind.getLocation(), DiagID)
+        << DestType << (bool)DestType->getAs<RecordType>()
+        << FixItHint::CreateInsertion(ZeroInitializationFixitLoc,
+                                      ZeroInitializationFixit);
+  }
+
+  if (getKind() == DependentSequence) {
+    // If the declaration is a non-dependent, incomplete array type
+    // that has an initializer, then its type will be completed once
+    // the initializer is instantiated.
+    if (ResultType && !Entity.getType()->isDependentType() &&
+        Args.size() == 1) {
+      QualType DeclType = Entity.getType();
+      if (const IncompleteArrayType *ArrayT
+                           = S.Context.getAsIncompleteArrayType(DeclType)) {
+        // FIXME: We don't currently have the ability to accurately
+        // compute the length of an initializer list without
+        // performing full type-checking of the initializer list
+        // (since we have to determine where braces are implicitly
+        // introduced and such).  So, we fall back to making the array
+        // type a dependently-sized array type with no specified
+        // bound.
+        if (isa<InitListExpr>((Expr *)Args[0])) {
+          SourceRange Brackets;
+
+          // Scavange the location of the brackets from the entity, if we can.
+          if (auto *DD = dyn_cast_or_null<DeclaratorDecl>(Entity.getDecl())) {
+            if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) {
+              TypeLoc TL = TInfo->getTypeLoc();
+              if (IncompleteArrayTypeLoc ArrayLoc =
+                      TL.getAs<IncompleteArrayTypeLoc>())
+                Brackets = ArrayLoc.getBracketsRange();
+            }
+          }
+
+          *ResultType
+            = S.Context.getDependentSizedArrayType(ArrayT->getElementType(),
+                                                   /*NumElts=*/nullptr,
+                                                   ArrayT->getSizeModifier(),
+                                       ArrayT->getIndexTypeCVRQualifiers(),
+                                                   Brackets);
+        }
+
+      }
+    }
+    if (Kind.getKind() == InitializationKind::IK_Direct &&
+        !Kind.isExplicitCast()) {
+      // Rebuild the ParenListExpr.
+      SourceRange ParenRange = Kind.getParenOrBraceRange();
+      return S.ActOnParenListExpr(ParenRange.getBegin(), ParenRange.getEnd(),
+                                  Args);
+    }
+    assert(Kind.getKind() == InitializationKind::IK_Copy ||
+           Kind.isExplicitCast() ||
+           Kind.getKind() == InitializationKind::IK_DirectList);
+    return ExprResult(Args[0]);
+  }
+
+  // No steps means no initialization.
+  if (Steps.empty())
+    return ExprResult((Expr *)nullptr);
+
+  if (S.getLangOpts().CPlusPlus11 && Entity.getType()->isReferenceType() &&
+      Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
+      !Entity.isParameterKind()) {
+    // Produce a C++98 compatibility warning if we are initializing a reference
+    // from an initializer list. For parameters, we produce a better warning
+    // elsewhere.
+    Expr *Init = Args[0];
+    S.Diag(Init->getBeginLoc(), diag::warn_cxx98_compat_reference_list_init)
+        << Init->getSourceRange();
+  }
+
+  // OpenCL v2.0 s6.13.11.1. atomic variables can be initialized in global scope
+  QualType ETy = Entity.getType();
+  Qualifiers TyQualifiers = ETy.getQualifiers();
+  bool HasGlobalAS = TyQualifiers.hasAddressSpace() &&
+                     TyQualifiers.getAddressSpace() == LangAS::opencl_global;
+
+  if (S.getLangOpts().OpenCLVersion >= 200 &&
+      ETy->isAtomicType() && !HasGlobalAS &&
+      Entity.getKind() == InitializedEntity::EK_Variable && Args.size() > 0) {
+    S.Diag(Args[0]->getBeginLoc(), diag::err_opencl_atomic_init)
+        << 1
+        << SourceRange(Entity.getDecl()->getBeginLoc(), Args[0]->getEndLoc());
+    return ExprError();
+  }
+
+  QualType DestType = Entity.getType().getNonReferenceType();
+  // FIXME: Ugly hack around the fact that Entity.getType() is not
+  // the same as Entity.getDecl()->getType() in cases involving type merging,
+  //  and we want latter when it makes sense.
+  if (ResultType)
+    *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() :
+                                     Entity.getType();
+
+  ExprResult CurInit((Expr *)nullptr);
+  SmallVector<Expr*, 4> ArrayLoopCommonExprs;
+
+  // For initialization steps that start with a single initializer,
+  // grab the only argument out the Args and place it into the "current"
+  // initializer.
+  switch (Steps.front().Kind) {
+  case SK_ResolveAddressOfOverloadedFunction:
+  case SK_CastDerivedToBaseRValue:
+  case SK_CastDerivedToBaseXValue:
+  case SK_CastDerivedToBaseLValue:
+  case SK_BindReference:
+  case SK_BindReferenceToTemporary:
+  case SK_FinalCopy:
+  case SK_ExtraneousCopyToTemporary:
+  case SK_UserConversion:
+  case SK_QualificationConversionLValue:
+  case SK_QualificationConversionXValue:
+  case SK_QualificationConversionRValue:
+  case SK_AtomicConversion:
+  case SK_ConversionSequence:
+  case SK_ConversionSequenceNoNarrowing:
+  case SK_ListInitialization:
+  case SK_UnwrapInitList:
+  case SK_RewrapInitList:
+  case SK_CAssignment:
+  case SK_StringInit:
+  case SK_ObjCObjectConversion:
+  case SK_ArrayLoopIndex:
+  case SK_ArrayLoopInit:
+  case SK_ArrayInit:
+  case SK_GNUArrayInit:
+  case SK_ParenthesizedArrayInit:
+  case SK_PassByIndirectCopyRestore:
+  case SK_PassByIndirectRestore:
+  case SK_ProduceObjCObject:
+  case SK_StdInitializerList:
+  case SK_OCLSamplerInit:
+  case SK_OCLZeroOpaqueType: {
+    assert(Args.size() == 1);
+    CurInit = Args[0];
+    if (!CurInit.get()) return ExprError();
+    break;
+  }
+
+  case SK_ConstructorInitialization:
+  case SK_ConstructorInitializationFromList:
+  case SK_StdInitializerListConstructorCall:
+  case SK_ZeroInitialization:
+    break;
+  }
+
+  // Promote from an unevaluated context to an unevaluated list context in
+  // C++11 list-initialization; we need to instantiate entities usable in
+  // constant expressions here in order to perform narrowing checks =(
+  EnterExpressionEvaluationContext Evaluated(
+      S, EnterExpressionEvaluationContext::InitList,
+      CurInit.get() && isa<InitListExpr>(CurInit.get()));
+
+  // C++ [class.abstract]p2:
+  //   no objects of an abstract class can be created except as subobjects
+  //   of a class derived from it
+  auto checkAbstractType = [&](QualType T) -> bool {
+    if (Entity.getKind() == InitializedEntity::EK_Base ||
+        Entity.getKind() == InitializedEntity::EK_Delegating)
+      return false;
+    return S.RequireNonAbstractType(Kind.getLocation(), T,
+                                    diag::err_allocation_of_abstract_type);
+  };
+
+  // Walk through the computed steps for the initialization sequence,
+  // performing the specified conversions along the way.
+  bool ConstructorInitRequiresZeroInit = false;
+  for (step_iterator Step = step_begin(), StepEnd = step_end();
+       Step != StepEnd; ++Step) {
+    if (CurInit.isInvalid())
+      return ExprError();
+
+    QualType SourceType = CurInit.get() ? CurInit.get()->getType() : QualType();
+
+    switch (Step->Kind) {
+    case SK_ResolveAddressOfOverloadedFunction:
+      // Overload resolution determined which function invoke; update the
+      // initializer to reflect that choice.
+      S.CheckAddressOfMemberAccess(CurInit.get(), Step->Function.FoundDecl);
+      if (S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation()))
+        return ExprError();
+      CurInit = S.FixOverloadedFunctionReference(CurInit,
+                                                 Step->Function.FoundDecl,
+                                                 Step->Function.Function);
+      break;
+
+    case SK_CastDerivedToBaseRValue:
+    case SK_CastDerivedToBaseXValue:
+    case SK_CastDerivedToBaseLValue: {
+      // We have a derived-to-base cast that produces either an rvalue or an
+      // lvalue. Perform that cast.
+
+      CXXCastPath BasePath;
+
+      // Casts to inaccessible base classes are allowed with C-style casts.
+      bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast();
+      if (S.CheckDerivedToBaseConversion(
+              SourceType, Step->Type, CurInit.get()->getBeginLoc(),
+              CurInit.get()->getSourceRange(), &BasePath, IgnoreBaseAccess))
+        return ExprError();
+
+      ExprValueKind VK =
+          Step->Kind == SK_CastDerivedToBaseLValue ?
+              VK_LValue :
+              (Step->Kind == SK_CastDerivedToBaseXValue ?
+                   VK_XValue :
+                   VK_RValue);
+      CurInit =
+          ImplicitCastExpr::Create(S.Context, Step->Type, CK_DerivedToBase,
+                                   CurInit.get(), &BasePath, VK);
+      break;
+    }
+
+    case SK_BindReference:
+      // Reference binding does not have any corresponding ASTs.
+
+      // Check exception specifications
+      if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
+        return ExprError();
+
+      // We don't check for e.g. function pointers here, since address
+      // availability checks should only occur when the function first decays
+      // into a pointer or reference.
+      if (CurInit.get()->getType()->isFunctionProtoType()) {
+        if (auto *DRE = dyn_cast<DeclRefExpr>(CurInit.get()->IgnoreParens())) {
+          if (auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
+            if (!S.checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
+                                                     DRE->getBeginLoc()))
+              return ExprError();
+          }
+        }
+      }
+
+      CheckForNullPointerDereference(S, CurInit.get());
+      break;
+
+    case SK_BindReferenceToTemporary: {
+      // Make sure the "temporary" is actually an rvalue.
+      assert(CurInit.get()->isRValue() && "not a temporary");
+
+      // Check exception specifications
+      if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
+        return ExprError();
+
+      // Materialize the temporary into memory.
+      MaterializeTemporaryExpr *MTE = S.CreateMaterializeTemporaryExpr(
+          Step->Type, CurInit.get(), Entity.getType()->isLValueReferenceType());
+      CurInit = MTE;
+
+      // If we're extending this temporary to automatic storage duration -- we
+      // need to register its cleanup during the full-expression's cleanups.
+      if (MTE->getStorageDuration() == SD_Automatic &&
+          MTE->getType().isDestructedType())
+        S.Cleanup.setExprNeedsCleanups(true);
+      break;
+    }
+
+    case SK_FinalCopy:
+      if (checkAbstractType(Step->Type))
+        return ExprError();
+
+      // If the overall initialization is initializing a temporary, we already
+      // bound our argument if it was necessary to do so. If not (if we're
+      // ultimately initializing a non-temporary), our argument needs to be
+      // bound since it's initializing a function parameter.
+      // FIXME: This is a mess. Rationalize temporary destruction.
+      if (!shouldBindAsTemporary(Entity))
+        CurInit = S.MaybeBindToTemporary(CurInit.get());
+      CurInit = CopyObject(S, Step->Type, Entity, CurInit,
+                           /*IsExtraneousCopy=*/false);
+      break;
+
+    case SK_ExtraneousCopyToTemporary:
+      CurInit = CopyObject(S, Step->Type, Entity, CurInit,
+                           /*IsExtraneousCopy=*/true);
+      break;
+
+    case SK_UserConversion: {
+      // We have a user-defined conversion that invokes either a constructor
+      // or a conversion function.
+      CastKind CastKind;
+      FunctionDecl *Fn = Step->Function.Function;
+      DeclAccessPair FoundFn = Step->Function.FoundDecl;
+      bool HadMultipleCandidates = Step->Function.HadMultipleCandidates;
+      bool CreatedObject = false;
+      if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) {
+        // Build a call to the selected constructor.
+        SmallVector<Expr*, 8> ConstructorArgs;
+        SourceLocation Loc = CurInit.get()->getBeginLoc();
+
+        // Determine the arguments required to actually perform the constructor
+        // call.
+        Expr *Arg = CurInit.get();
+        if (S.CompleteConstructorCall(Constructor,
+                                      MultiExprArg(&Arg, 1),
+                                      Loc, ConstructorArgs))
+          return ExprError();
+
+        // Build an expression that constructs a temporary.
+        CurInit = S.BuildCXXConstructExpr(Loc, Step->Type,
+                                          FoundFn, Constructor,
+                                          ConstructorArgs,
+                                          HadMultipleCandidates,
+                                          /*ListInit*/ false,
+                                          /*StdInitListInit*/ false,
+                                          /*ZeroInit*/ false,
+                                          CXXConstructExpr::CK_Complete,
+                                          SourceRange());
+        if (CurInit.isInvalid())
+          return ExprError();
+
+        S.CheckConstructorAccess(Kind.getLocation(), Constructor, FoundFn,
+                                 Entity);
+        if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
+          return ExprError();
+
+        CastKind = CK_ConstructorConversion;
+        CreatedObject = true;
+      } else {
+        // Build a call to the conversion function.
+        CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn);
+        S.CheckMemberOperatorAccess(Kind.getLocation(), CurInit.get(), nullptr,
+                                    FoundFn);
+        if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
+          return ExprError();
+
+        CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion,
+                                           HadMultipleCandidates);
+        if (CurInit.isInvalid())
+          return ExprError();
+
+        CastKind = CK_UserDefinedConversion;
+        CreatedObject = Conversion->getReturnType()->isRecordType();
+      }
+
+      if (CreatedObject && checkAbstractType(CurInit.get()->getType()))
+        return ExprError();
+
+      CurInit = ImplicitCastExpr::Create(S.Context, CurInit.get()->getType(),
+                                         CastKind, CurInit.get(), nullptr,
+                                         CurInit.get()->getValueKind());
+
+      if (shouldBindAsTemporary(Entity))
+        // The overall entity is temporary, so this expression should be
+        // destroyed at the end of its full-expression.
+        CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
+      else if (CreatedObject && shouldDestroyEntity(Entity)) {
+        // The object outlasts the full-expression, but we need to prepare for
+        // a destructor being run on it.
+        // FIXME: It makes no sense to do this here. This should happen
+        // regardless of how we initialized the entity.
+        QualType T = CurInit.get()->getType();
+        if (const RecordType *Record = T->getAs<RecordType>()) {
+          CXXDestructorDecl *Destructor
+            = S.LookupDestructor(cast<CXXRecordDecl>(Record->getDecl()));
+          S.CheckDestructorAccess(CurInit.get()->getBeginLoc(), Destructor,
+                                  S.PDiag(diag::err_access_dtor_temp) << T);
+          S.MarkFunctionReferenced(CurInit.get()->getBeginLoc(), Destructor);
+          if (S.DiagnoseUseOfDecl(Destructor, CurInit.get()->getBeginLoc()))
+            return ExprError();
+        }
+      }
+      break;
+    }
+
+    case SK_QualificationConversionLValue:
+    case SK_QualificationConversionXValue:
+    case SK_QualificationConversionRValue: {
+      // Perform a qualification conversion; these can never go wrong.
+      ExprValueKind VK =
+          Step->Kind == SK_QualificationConversionLValue
+              ? VK_LValue
+              : (Step->Kind == SK_QualificationConversionXValue ? VK_XValue
+                                                                : VK_RValue);
+      CurInit = S.PerformQualificationConversion(CurInit.get(), Step->Type, VK);
+      break;
+    }
+
+    case SK_AtomicConversion: {
+      assert(CurInit.get()->isRValue() && "cannot convert glvalue to atomic");
+      CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
+                                    CK_NonAtomicToAtomic, VK_RValue);
+      break;
+    }
+
+    case SK_ConversionSequence:
+    case SK_ConversionSequenceNoNarrowing: {
+      if (const auto *FromPtrType =
+              CurInit.get()->getType()->getAs<PointerType>()) {
+        if (const auto *ToPtrType = Step->Type->getAs<PointerType>()) {
+          if (FromPtrType->getPointeeType()->hasAttr(attr::NoDeref) &&
+              !ToPtrType->getPointeeType()->hasAttr(attr::NoDeref)) {
+            S.Diag(CurInit.get()->getExprLoc(),
+                   diag::warn_noderef_to_dereferenceable_pointer)
+                << CurInit.get()->getSourceRange();
+          }
+        }
+      }
+
+      Sema::CheckedConversionKind CCK
+        = Kind.isCStyleCast()? Sema::CCK_CStyleCast
+        : Kind.isFunctionalCast()? Sema::CCK_FunctionalCast
+        : Kind.isExplicitCast()? Sema::CCK_OtherCast
+        : Sema::CCK_ImplicitConversion;
+      ExprResult CurInitExprRes =
+        S.PerformImplicitConversion(CurInit.get(), Step->Type, *Step->ICS,
+                                    getAssignmentAction(Entity), CCK);
+      if (CurInitExprRes.isInvalid())
+        return ExprError();
+
+      S.DiscardMisalignedMemberAddress(Step->Type.getTypePtr(), CurInit.get());
+
+      CurInit = CurInitExprRes;
+
+      if (Step->Kind == SK_ConversionSequenceNoNarrowing &&
+          S.getLangOpts().CPlusPlus)
+        DiagnoseNarrowingInInitList(S, *Step->ICS, SourceType, Entity.getType(),
+                                    CurInit.get());
+
+      break;
+    }
+
+    case SK_ListInitialization: {
+      if (checkAbstractType(Step->Type))
+        return ExprError();
+
+      InitListExpr *InitList = cast<InitListExpr>(CurInit.get());
+      // If we're not initializing the top-level entity, we need to create an
+      // InitializeTemporary entity for our target type.
+      QualType Ty = Step->Type;
+      bool IsTemporary = !S.Context.hasSameType(Entity.getType(), Ty);
+      InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(Ty);
+      InitializedEntity InitEntity = IsTemporary ? TempEntity : Entity;
+      InitListChecker PerformInitList(S, InitEntity,
+          InitList, Ty, /*VerifyOnly=*/false,
+          /*TreatUnavailableAsInvalid=*/false);
+      if (PerformInitList.HadError())
+        return ExprError();
+
+      // Hack: We must update *ResultType if available in order to set the
+      // bounds of arrays, e.g. in 'int ar[] = {1, 2, 3};'.
+      // Worst case: 'const int (&arref)[] = {1, 2, 3};'.
+      if (ResultType &&
+          ResultType->getNonReferenceType()->isIncompleteArrayType()) {
+        if ((*ResultType)->isRValueReferenceType())
+          Ty = S.Context.getRValueReferenceType(Ty);
+        else if ((*ResultType)->isLValueReferenceType())
+          Ty = S.Context.getLValueReferenceType(Ty,
+            (*ResultType)->getAs<LValueReferenceType>()->isSpelledAsLValue());
+        *ResultType = Ty;
+      }
+
+      InitListExpr *StructuredInitList =
+          PerformInitList.getFullyStructuredList();
+      CurInit.get();
+      CurInit = shouldBindAsTemporary(InitEntity)
+          ? S.MaybeBindToTemporary(StructuredInitList)
+          : StructuredInitList;
+      break;
+    }
+
+    case SK_ConstructorInitializationFromList: {
+      if (checkAbstractType(Step->Type))
+        return ExprError();
+
+      // When an initializer list is passed for a parameter of type "reference
+      // to object", we don't get an EK_Temporary entity, but instead an
+      // EK_Parameter entity with reference type.
+      // FIXME: This is a hack. What we really should do is create a user
+      // conversion step for this case, but this makes it considerably more
+      // complicated. For now, this will do.
+      InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
+                                        Entity.getType().getNonReferenceType());
+      bool UseTemporary = Entity.getType()->isReferenceType();
+      assert(Args.size() == 1 && "expected a single argument for list init");
+      InitListExpr *InitList = cast<InitListExpr>(Args[0]);
+      S.Diag(InitList->getExprLoc(), diag::warn_cxx98_compat_ctor_list_init)
+        << InitList->getSourceRange();
+      MultiExprArg Arg(InitList->getInits(), InitList->getNumInits());
+      CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity :
+                                                                   Entity,
+                                                 Kind, Arg, *Step,
+                                               ConstructorInitRequiresZeroInit,
+                                               /*IsListInitialization*/true,
+                                               /*IsStdInitListInit*/false,
+                                               InitList->getLBraceLoc(),
+                                               InitList->getRBraceLoc());
+      break;
+    }
+
+    case SK_UnwrapInitList:
+      CurInit = cast<InitListExpr>(CurInit.get())->getInit(0);
+      break;
+
+    case SK_RewrapInitList: {
+      Expr *E = CurInit.get();
+      InitListExpr *Syntactic = Step->WrappingSyntacticList;
+      InitListExpr *ILE = new (S.Context) InitListExpr(S.Context,
+          Syntactic->getLBraceLoc(), E, Syntactic->getRBraceLoc());
+      ILE->setSyntacticForm(Syntactic);
+      ILE->setType(E->getType());
+      ILE->setValueKind(E->getValueKind());
+      CurInit = ILE;
+      break;
+    }
+
+    case SK_ConstructorInitialization:
+    case SK_StdInitializerListConstructorCall: {
+      if (checkAbstractType(Step->Type))
+        return ExprError();
+
+      // When an initializer list is passed for a parameter of type "reference
+      // to object", we don't get an EK_Temporary entity, but instead an
+      // EK_Parameter entity with reference type.
+      // FIXME: This is a hack. What we really should do is create a user
+      // conversion step for this case, but this makes it considerably more
+      // complicated. For now, this will do.
+      InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
+                                        Entity.getType().getNonReferenceType());
+      bool UseTemporary = Entity.getType()->isReferenceType();
+      bool IsStdInitListInit =
+          Step->Kind == SK_StdInitializerListConstructorCall;
+      Expr *Source = CurInit.get();
+      SourceRange Range = Kind.hasParenOrBraceRange()
+                              ? Kind.getParenOrBraceRange()
+                              : SourceRange();
+      CurInit = PerformConstructorInitialization(
+          S, UseTemporary ? TempEntity : Entity, Kind,
+          Source ? MultiExprArg(Source) : Args, *Step,
+          ConstructorInitRequiresZeroInit,
+          /*IsListInitialization*/ IsStdInitListInit,
+          /*IsStdInitListInitialization*/ IsStdInitListInit,
+          /*LBraceLoc*/ Range.getBegin(),
+          /*RBraceLoc*/ Range.getEnd());
+      break;
+    }
+
+    case SK_ZeroInitialization: {
+      step_iterator NextStep = Step;
+      ++NextStep;
+      if (NextStep != StepEnd &&
+          (NextStep->Kind == SK_ConstructorInitialization ||
+           NextStep->Kind == SK_ConstructorInitializationFromList)) {
+        // The need for zero-initialization is recorded directly into
+        // the call to the object's constructor within the next step.
+        ConstructorInitRequiresZeroInit = true;
+      } else if (Kind.getKind() == InitializationKind::IK_Value &&
+                 S.getLangOpts().CPlusPlus &&
+                 !Kind.isImplicitValueInit()) {
+        TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
+        if (!TSInfo)
+          TSInfo = S.Context.getTrivialTypeSourceInfo(Step->Type,
+                                                    Kind.getRange().getBegin());
+
+        CurInit = new (S.Context) CXXScalarValueInitExpr(
+            Entity.getType().getNonLValueExprType(S.Context), TSInfo,
+            Kind.getRange().getEnd());
+      } else {
+        CurInit = new (S.Context) ImplicitValueInitExpr(Step->Type);
+      }
+      break;
+    }
+
+    case SK_CAssignment: {
+      QualType SourceType = CurInit.get()->getType();
+
+      // Save off the initial CurInit in case we need to emit a diagnostic
+      ExprResult InitialCurInit = CurInit;
+      ExprResult Result = CurInit;
+      Sema::AssignConvertType ConvTy =
+        S.CheckSingleAssignmentConstraints(Step->Type, Result, true,
+            Entity.getKind() == InitializedEntity::EK_Parameter_CF_Audited);
+      if (Result.isInvalid())
+        return ExprError();
+      CurInit = Result;
+
+      // If this is a call, allow conversion to a transparent union.
+      ExprResult CurInitExprRes = CurInit;
+      if (ConvTy != Sema::Compatible &&
+          Entity.isParameterKind() &&
+          S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExprRes)
+            == Sema::Compatible)
+        ConvTy = Sema::Compatible;
+      if (CurInitExprRes.isInvalid())
+        return ExprError();
+      CurInit = CurInitExprRes;
+
+      bool Complained;
+      if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(),
+                                     Step->Type, SourceType,
+                                     InitialCurInit.get(),
+                                     getAssignmentAction(Entity, true),
+                                     &Complained)) {
+        PrintInitLocationNote(S, Entity);
+        return ExprError();
+      } else if (Complained)
+        PrintInitLocationNote(S, Entity);
+      break;
+    }
+
+    case SK_StringInit: {
+      QualType Ty = Step->Type;
+      CheckStringInit(CurInit.get(), ResultType ? *ResultType : Ty,
+                      S.Context.getAsArrayType(Ty), S);
+      break;
+    }
+
+    case SK_ObjCObjectConversion:
+      CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
+                          CK_ObjCObjectLValueCast,
+                          CurInit.get()->getValueKind());
+      break;
+
+    case SK_ArrayLoopIndex: {
+      Expr *Cur = CurInit.get();
+      Expr *BaseExpr = new (S.Context)
+          OpaqueValueExpr(Cur->getExprLoc(), Cur->getType(),
+                          Cur->getValueKind(), Cur->getObjectKind(), Cur);
+      Expr *IndexExpr =
+          new (S.Context) ArrayInitIndexExpr(S.Context.getSizeType());
+      CurInit = S.CreateBuiltinArraySubscriptExpr(
+          BaseExpr, Kind.getLocation(), IndexExpr, Kind.getLocation());
+      ArrayLoopCommonExprs.push_back(BaseExpr);
+      break;
+    }
+
+    case SK_ArrayLoopInit: {
+      assert(!ArrayLoopCommonExprs.empty() &&
+             "mismatched SK_ArrayLoopIndex and SK_ArrayLoopInit");
+      Expr *Common = ArrayLoopCommonExprs.pop_back_val();
+      CurInit = new (S.Context) ArrayInitLoopExpr(Step->Type, Common,
+                                                  CurInit.get());
+      break;
+    }
+
+    case SK_GNUArrayInit:
+      // Okay: we checked everything before creating this step. Note that
+      // this is a GNU extension.
+      S.Diag(Kind.getLocation(), diag::ext_array_init_copy)
+        << Step->Type << CurInit.get()->getType()
+        << CurInit.get()->getSourceRange();
+      updateGNUCompoundLiteralRValue(CurInit.get());
+      LLVM_FALLTHROUGH;
+    case SK_ArrayInit:
+      // If the destination type is an incomplete array type, update the
+      // type accordingly.
+      if (ResultType) {
+        if (const IncompleteArrayType *IncompleteDest
+                           = S.Context.getAsIncompleteArrayType(Step->Type)) {
+          if (const ConstantArrayType *ConstantSource
+                 = S.Context.getAsConstantArrayType(CurInit.get()->getType())) {
+            *ResultType = S.Context.getConstantArrayType(
+                                             IncompleteDest->getElementType(),
+                                             ConstantSource->getSize(),
+                                             ArrayType::Normal, 0);
+          }
+        }
+      }
+      break;
+
+    case SK_ParenthesizedArrayInit:
+      // Okay: we checked everything before creating this step. Note that
+      // this is a GNU extension.
+      S.Diag(Kind.getLocation(), diag::ext_array_init_parens)
+        << CurInit.get()->getSourceRange();
+      break;
+
+    case SK_PassByIndirectCopyRestore:
+    case SK_PassByIndirectRestore:
+      checkIndirectCopyRestoreSource(S, CurInit.get());
+      CurInit = new (S.Context) ObjCIndirectCopyRestoreExpr(
+          CurInit.get(), Step->Type,
+          Step->Kind == SK_PassByIndirectCopyRestore);
+      break;
+
+    case SK_ProduceObjCObject:
+      CurInit =
+          ImplicitCastExpr::Create(S.Context, Step->Type, CK_ARCProduceObject,
+                                   CurInit.get(), nullptr, VK_RValue);
+      break;
+
+    case SK_StdInitializerList: {
+      S.Diag(CurInit.get()->getExprLoc(),
+             diag::warn_cxx98_compat_initializer_list_init)
+        << CurInit.get()->getSourceRange();
+
+      // Materialize the temporary into memory.
+      MaterializeTemporaryExpr *MTE = S.CreateMaterializeTemporaryExpr(
+          CurInit.get()->getType(), CurInit.get(),
+          /*BoundToLvalueReference=*/false);
+
+      // Wrap it in a construction of a std::initializer_list<T>.
+      CurInit = new (S.Context) CXXStdInitializerListExpr(Step->Type, MTE);
+
+      // Bind the result, in case the library has given initializer_list a
+      // non-trivial destructor.
+      if (shouldBindAsTemporary(Entity))
+        CurInit = S.MaybeBindToTemporary(CurInit.get());
+      break;
+    }
+
+    case SK_OCLSamplerInit: {
+      // Sampler initialization have 5 cases:
+      //   1. function argument passing
+      //      1a. argument is a file-scope variable
+      //      1b. argument is a function-scope variable
+      //      1c. argument is one of caller function's parameters
+      //   2. variable initialization
+      //      2a. initializing a file-scope variable
+      //      2b. initializing a function-scope variable
+      //
+      // For file-scope variables, since they cannot be initialized by function
+      // call of __translate_sampler_initializer in LLVM IR, their references
+      // need to be replaced by a cast from their literal initializers to
+      // sampler type. Since sampler variables can only be used in function
+      // calls as arguments, we only need to replace them when handling the
+      // argument passing.
+      assert(Step->Type->isSamplerT() &&
+             "Sampler initialization on non-sampler type.");
+      Expr *Init = CurInit.get()->IgnoreParens();
+      QualType SourceType = Init->getType();
+      // Case 1
+      if (Entity.isParameterKind()) {
+        if (!SourceType->isSamplerT() && !SourceType->isIntegerType()) {
+          S.Diag(Kind.getLocation(), diag::err_sampler_argument_required)
+            << SourceType;
+          break;
+        } else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Init)) {
+          auto Var = cast<VarDecl>(DRE->getDecl());
+          // Case 1b and 1c
+          // No cast from integer to sampler is needed.
+          if (!Var->hasGlobalStorage()) {
+            CurInit = ImplicitCastExpr::Create(S.Context, Step->Type,
+                                               CK_LValueToRValue, Init,
+                                               /*BasePath=*/nullptr, VK_RValue);
+            break;
+          }
+          // Case 1a
+          // For function call with a file-scope sampler variable as argument,
+          // get the integer literal.
+          // Do not diagnose if the file-scope variable does not have initializer
+          // since this has already been diagnosed when parsing the variable
+          // declaration.
+          if (!Var->getInit() || !isa<ImplicitCastExpr>(Var->getInit()))
+            break;
+          Init = cast<ImplicitCastExpr>(const_cast<Expr*>(
+            Var->getInit()))->getSubExpr();
+          SourceType = Init->getType();
+        }
+      } else {
+        // Case 2
+        // Check initializer is 32 bit integer constant.
+        // If the initializer is taken from global variable, do not diagnose since
+        // this has already been done when parsing the variable declaration.
+        if (!Init->isConstantInitializer(S.Context, false))
+          break;
+
+        if (!SourceType->isIntegerType() ||
+            32 != S.Context.getIntWidth(SourceType)) {
+          S.Diag(Kind.getLocation(), diag::err_sampler_initializer_not_integer)
+            << SourceType;
+          break;
+        }
+
+        Expr::EvalResult EVResult;
+        Init->EvaluateAsInt(EVResult, S.Context);
+        llvm::APSInt Result = EVResult.Val.getInt();
+        const uint64_t SamplerValue = Result.getLimitedValue();
+        // 32-bit value of sampler's initializer is interpreted as
+        // bit-field with the following structure:
+        // |unspecified|Filter|Addressing Mode| Normalized Coords|
+        // |31        6|5    4|3             1|                 0|
+        // This structure corresponds to enum values of sampler properties
+        // defined in SPIR spec v1.2 and also opencl-c.h
+        unsigned AddressingMode  = (0x0E & SamplerValue) >> 1;
+        unsigned FilterMode      = (0x30 & SamplerValue) >> 4;
+        if (FilterMode != 1 && FilterMode != 2 &&
+            !S.getOpenCLOptions().isEnabled(
+                "cl_intel_device_side_avc_motion_estimation"))
+          S.Diag(Kind.getLocation(),
+                 diag::warn_sampler_initializer_invalid_bits)
+                 << "Filter Mode";
+        if (AddressingMode > 4)
+          S.Diag(Kind.getLocation(),
+                 diag::warn_sampler_initializer_invalid_bits)
+                 << "Addressing Mode";
+      }
+
+      // Cases 1a, 2a and 2b
+      // Insert cast from integer to sampler.
+      CurInit = S.ImpCastExprToType(Init, S.Context.OCLSamplerTy,
+                                      CK_IntToOCLSampler);
+      break;
+    }
+    case SK_OCLZeroOpaqueType: {
+      assert((Step->Type->isEventT() || Step->Type->isQueueT() ||
+              Step->Type->isOCLIntelSubgroupAVCType()) &&
+             "Wrong type for initialization of OpenCL opaque type.");
+
+      CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
+                                    CK_ZeroToOCLOpaqueType,
+                                    CurInit.get()->getValueKind());
+      break;
+    }
+    }
+  }
+
+  // Check whether the initializer has a shorter lifetime than the initialized
+  // entity, and if not, either lifetime-extend or warn as appropriate.
+  if (auto *Init = CurInit.get())
+    S.checkInitializerLifetime(Entity, Init);
+
+  // Diagnose non-fatal problems with the completed initialization.
+  if (Entity.getKind() == InitializedEntity::EK_Member &&
+      cast<FieldDecl>(Entity.getDecl())->isBitField())
+    S.CheckBitFieldInitialization(Kind.getLocation(),
+                                  cast<FieldDecl>(Entity.getDecl()),
+                                  CurInit.get());
+
+  // Check for std::move on construction.
+  if (const Expr *E = CurInit.get()) {
+    CheckMoveOnConstruction(S, E,
+                            Entity.getKind() == InitializedEntity::EK_Result);
+  }
+
+  return CurInit;
+}
+
+/// Somewhere within T there is an uninitialized reference subobject.
+/// Dig it out and diagnose it.
+static bool DiagnoseUninitializedReference(Sema &S, SourceLocation Loc,
+                                           QualType T) {
+  if (T->isReferenceType()) {
+    S.Diag(Loc, diag::err_reference_without_init)
+      << T.getNonReferenceType();
+    return true;
+  }
+
+  CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
+  if (!RD || !RD->hasUninitializedReferenceMember())
+    return false;
+
+  for (const auto *FI : RD->fields()) {
+    if (FI->isUnnamedBitfield())
+      continue;
+
+    if (DiagnoseUninitializedReference(S, FI->getLocation(), FI->getType())) {
+      S.Diag(Loc, diag::note_value_initialization_here) << RD;
+      return true;
+    }
+  }
+
+  for (const auto &BI : RD->bases()) {
+    if (DiagnoseUninitializedReference(S, BI.getBeginLoc(), BI.getType())) {
+      S.Diag(Loc, diag::note_value_initialization_here) << RD;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+
+//===----------------------------------------------------------------------===//
+// Diagnose initialization failures
+//===----------------------------------------------------------------------===//
+
+/// Emit notes associated with an initialization that failed due to a
+/// "simple" conversion failure.
+static void emitBadConversionNotes(Sema &S, const InitializedEntity &entity,
+                                   Expr *op) {
+  QualType destType = entity.getType();
+  if (destType.getNonReferenceType()->isObjCObjectPointerType() &&
+      op->getType()->isObjCObjectPointerType()) {
+
+    // Emit a possible note about the conversion failing because the
+    // operand is a message send with a related result type.
+    S.EmitRelatedResultTypeNote(op);
+
+    // Emit a possible note about a return failing because we're
+    // expecting a related result type.
+    if (entity.getKind() == InitializedEntity::EK_Result)
+      S.EmitRelatedResultTypeNoteForReturn(destType);
+  }
+}
+
+static void diagnoseListInit(Sema &S, const InitializedEntity &Entity,
+                             InitListExpr *InitList) {
+  QualType DestType = Entity.getType();
+
+  QualType E;
+  if (S.getLangOpts().CPlusPlus11 && S.isStdInitializerList(DestType, &E)) {
+    QualType ArrayType = S.Context.getConstantArrayType(
+        E.withConst(),
+        llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
+                    InitList->getNumInits()),
+        clang::ArrayType::Normal, 0);
+    InitializedEntity HiddenArray =
+        InitializedEntity::InitializeTemporary(ArrayType);
+    return diagnoseListInit(S, HiddenArray, InitList);
+  }
+
+  if (DestType->isReferenceType()) {
+    // A list-initialization failure for a reference means that we tried to
+    // create a temporary of the inner type (per [dcl.init.list]p3.6) and the
+    // inner initialization failed.
+    QualType T = DestType->getAs<ReferenceType>()->getPointeeType();
+    diagnoseListInit(S, InitializedEntity::InitializeTemporary(T), InitList);
+    SourceLocation Loc = InitList->getBeginLoc();
+    if (auto *D = Entity.getDecl())
+      Loc = D->getLocation();
+    S.Diag(Loc, diag::note_in_reference_temporary_list_initializer) << T;
+    return;
+  }
+
+  InitListChecker DiagnoseInitList(S, Entity, InitList, DestType,
+                                   /*VerifyOnly=*/false,
+                                   /*TreatUnavailableAsInvalid=*/false);
+  assert(DiagnoseInitList.HadError() &&
+         "Inconsistent init list check result.");
+}
+
+bool InitializationSequence::Diagnose(Sema &S,
+                                      const InitializedEntity &Entity,
+                                      const InitializationKind &Kind,
+                                      ArrayRef<Expr *> Args) {
+  if (!Failed())
+    return false;
+
+  // When we want to diagnose only one element of a braced-init-list,
+  // we need to factor it out.
+  Expr *OnlyArg;
+  if (Args.size() == 1) {
+    auto *List = dyn_cast<InitListExpr>(Args[0]);
+    if (List && List->getNumInits() == 1)
+      OnlyArg = List->getInit(0);
+    else
+      OnlyArg = Args[0];
+  }
+  else
+    OnlyArg = nullptr;
+
+  QualType DestType = Entity.getType();
+  switch (Failure) {
+  case FK_TooManyInitsForReference:
+    // FIXME: Customize for the initialized entity?
+    if (Args.empty()) {
+      // Dig out the reference subobject which is uninitialized and diagnose it.
+      // If this is value-initialization, this could be nested some way within
+      // the target type.
+      assert(Kind.getKind() == InitializationKind::IK_Value ||
+             DestType->isReferenceType());
+      bool Diagnosed =
+        DiagnoseUninitializedReference(S, Kind.getLocation(), DestType);
+      assert(Diagnosed && "couldn't find uninitialized reference to diagnose");
+      (void)Diagnosed;
+    } else  // FIXME: diagnostic below could be better!
+      S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits)
+          << SourceRange(Args.front()->getBeginLoc(), Args.back()->getEndLoc());
+    break;
+  case FK_ParenthesizedListInitForReference:
+    S.Diag(Kind.getLocation(), diag::err_list_init_in_parens)
+      << 1 << Entity.getType() << Args[0]->getSourceRange();
+    break;
+
+  case FK_ArrayNeedsInitList:
+    S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 0;
+    break;
+  case FK_ArrayNeedsInitListOrStringLiteral:
+    S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 1;
+    break;
+  case FK_ArrayNeedsInitListOrWideStringLiteral:
+    S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 2;
+    break;
+  case FK_NarrowStringIntoWideCharArray:
+    S.Diag(Kind.getLocation(), diag::err_array_init_narrow_string_into_wchar);
+    break;
+  case FK_WideStringIntoCharArray:
+    S.Diag(Kind.getLocation(), diag::err_array_init_wide_string_into_char);
+    break;
+  case FK_IncompatWideStringIntoWideChar:
+    S.Diag(Kind.getLocation(),
+           diag::err_array_init_incompat_wide_string_into_wchar);
+    break;
+  case FK_PlainStringIntoUTF8Char:
+    S.Diag(Kind.getLocation(),
+           diag::err_array_init_plain_string_into_char8_t);
+    S.Diag(Args.front()->getBeginLoc(),
+           diag::note_array_init_plain_string_into_char8_t)
+        << FixItHint::CreateInsertion(Args.front()->getBeginLoc(), "u8");
+    break;
+  case FK_UTF8StringIntoPlainChar:
+    S.Diag(Kind.getLocation(),
+           diag::err_array_init_utf8_string_into_char)
+      << S.getLangOpts().CPlusPlus2a;
+    break;
+  case FK_ArrayTypeMismatch:
+  case FK_NonConstantArrayInit:
+    S.Diag(Kind.getLocation(),
+           (Failure == FK_ArrayTypeMismatch
+              ? diag::err_array_init_different_type
+              : diag::err_array_init_non_constant_array))
+      << DestType.getNonReferenceType()
+      << OnlyArg->getType()
+      << Args[0]->getSourceRange();
+    break;
+
+  case FK_VariableLengthArrayHasInitializer:
+    S.Diag(Kind.getLocation(), diag::err_variable_object_no_init)
+      << Args[0]->getSourceRange();
+    break;
+
+  case FK_AddressOfOverloadFailed: {
+    DeclAccessPair Found;
+    S.ResolveAddressOfOverloadedFunction(OnlyArg,
+                                         DestType.getNonReferenceType(),
+                                         true,
+                                         Found);
+    break;
+  }
+
+  case FK_AddressOfUnaddressableFunction: {
+    auto *FD = cast<FunctionDecl>(cast<DeclRefExpr>(OnlyArg)->getDecl());
+    S.checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
+                                        OnlyArg->getBeginLoc());
+    break;
+  }
+
+  case FK_ReferenceInitOverloadFailed:
+  case FK_UserConversionOverloadFailed:
+    switch (FailedOverloadResult) {
+    case OR_Ambiguous:
+
+      FailedCandidateSet.NoteCandidates(
+          PartialDiagnosticAt(
+              Kind.getLocation(),
+              Failure == FK_UserConversionOverloadFailed
+                  ? (S.PDiag(diag::err_typecheck_ambiguous_condition)
+                     << OnlyArg->getType() << DestType
+                     << Args[0]->getSourceRange())
+                  : (S.PDiag(diag::err_ref_init_ambiguous)
+                     << DestType << OnlyArg->getType()
+                     << Args[0]->getSourceRange())),
+          S, OCD_ViableCandidates, Args);
+      break;
+
+    case OR_No_Viable_Function: {
+      auto Cands = FailedCandidateSet.CompleteCandidates(S, OCD_AllCandidates, Args);
+      if (!S.RequireCompleteType(Kind.getLocation(),
+                                 DestType.getNonReferenceType(),
+                          diag::err_typecheck_nonviable_condition_incomplete,
+                               OnlyArg->getType(), Args[0]->getSourceRange()))
+        S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition)
+          << (Entity.getKind() == InitializedEntity::EK_Result)
+          << OnlyArg->getType() << Args[0]->getSourceRange()
+          << DestType.getNonReferenceType();
+
+      FailedCandidateSet.NoteCandidates(S, Args, Cands);
+      break;
+    }
+    case OR_Deleted: {
+      S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function)
+        << OnlyArg->getType() << DestType.getNonReferenceType()
+        << Args[0]->getSourceRange();
+      OverloadCandidateSet::iterator Best;
+      OverloadingResult Ovl
+        = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
+      if (Ovl == OR_Deleted) {
+        S.NoteDeletedFunction(Best->Function);
+      } else {
+        llvm_unreachable("Inconsistent overload resolution?");
+      }
+      break;
+    }
+
+    case OR_Success:
+      llvm_unreachable("Conversion did not fail!");
+    }
+    break;
+
+  case FK_NonConstLValueReferenceBindingToTemporary:
+    if (isa<InitListExpr>(Args[0])) {
+      S.Diag(Kind.getLocation(),
+             diag::err_lvalue_reference_bind_to_initlist)
+      << DestType.getNonReferenceType().isVolatileQualified()
+      << DestType.getNonReferenceType()
+      << Args[0]->getSourceRange();
+      break;
+    }
+    LLVM_FALLTHROUGH;
+
+  case FK_NonConstLValueReferenceBindingToUnrelated:
+    S.Diag(Kind.getLocation(),
+           Failure == FK_NonConstLValueReferenceBindingToTemporary
+             ? diag::err_lvalue_reference_bind_to_temporary
+             : diag::err_lvalue_reference_bind_to_unrelated)
+      << DestType.getNonReferenceType().isVolatileQualified()
+      << DestType.getNonReferenceType()
+      << OnlyArg->getType()
+      << Args[0]->getSourceRange();
+    break;
+
+  case FK_NonConstLValueReferenceBindingToBitfield: {
+    // We don't necessarily have an unambiguous source bit-field.
+    FieldDecl *BitField = Args[0]->getSourceBitField();
+    S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield)
+      << DestType.isVolatileQualified()
+      << (BitField ? BitField->getDeclName() : DeclarationName())
+      << (BitField != nullptr)
+      << Args[0]->getSourceRange();
+    if (BitField)
+      S.Diag(BitField->getLocation(), diag::note_bitfield_decl);
+    break;
+  }
+
+  case FK_NonConstLValueReferenceBindingToVectorElement:
+    S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element)
+      << DestType.isVolatileQualified()
+      << Args[0]->getSourceRange();
+    break;
+
+  case FK_RValueReferenceBindingToLValue:
+    S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref)
+      << DestType.getNonReferenceType() << OnlyArg->getType()
+      << Args[0]->getSourceRange();
+    break;
+
+  case FK_ReferenceAddrspaceMismatchTemporary:
+    S.Diag(Kind.getLocation(), diag::err_reference_bind_temporary_addrspace)
+        << DestType << Args[0]->getSourceRange();
+    break;
+
+  case FK_ReferenceInitDropsQualifiers: {
+    QualType SourceType = OnlyArg->getType();
+    QualType NonRefType = DestType.getNonReferenceType();
+    Qualifiers DroppedQualifiers =
+        SourceType.getQualifiers() - NonRefType.getQualifiers();
+
+    if (!NonRefType.getQualifiers().isAddressSpaceSupersetOf(
+            SourceType.getQualifiers()))
+      S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals)
+          << NonRefType << SourceType << 1 /*addr space*/
+          << Args[0]->getSourceRange();
+    else
+      S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals)
+          << NonRefType << SourceType << 0 /*cv quals*/
+          << Qualifiers::fromCVRMask(DroppedQualifiers.getCVRQualifiers())
+          << DroppedQualifiers.getCVRQualifiers() << Args[0]->getSourceRange();
+    break;
+  }
+
+  case FK_ReferenceInitFailed:
+    S.Diag(Kind.getLocation(), diag::err_reference_bind_failed)
+      << DestType.getNonReferenceType()
+      << DestType.getNonReferenceType()->isIncompleteType()
+      << OnlyArg->isLValue()
+      << OnlyArg->getType()
+      << Args[0]->getSourceRange();
+    emitBadConversionNotes(S, Entity, Args[0]);
+    break;
+
+  case FK_ConversionFailed: {
+    QualType FromType = OnlyArg->getType();
+    PartialDiagnostic PDiag = S.PDiag(diag::err_init_conversion_failed)
+      << (int)Entity.getKind()
+      << DestType
+      << OnlyArg->isLValue()
+      << FromType
+      << Args[0]->getSourceRange();
+    S.HandleFunctionTypeMismatch(PDiag, FromType, DestType);
+    S.Diag(Kind.getLocation(), PDiag);
+    emitBadConversionNotes(S, Entity, Args[0]);
+    break;
+  }
+
+  case FK_ConversionFromPropertyFailed:
+    // No-op. This error has already been reported.
+    break;
+
+  case FK_TooManyInitsForScalar: {
+    SourceRange R;
+
+    auto *InitList = dyn_cast<InitListExpr>(Args[0]);
+    if (InitList && InitList->getNumInits() >= 1) {
+      R = SourceRange(InitList->getInit(0)->getEndLoc(), InitList->getEndLoc());
+    } else {
+      assert(Args.size() > 1 && "Expected multiple initializers!");
+      R = SourceRange(Args.front()->getEndLoc(), Args.back()->getEndLoc());
+    }
+
+    R.setBegin(S.getLocForEndOfToken(R.getBegin()));
+    if (Kind.isCStyleOrFunctionalCast())
+      S.Diag(Kind.getLocation(), diag::err_builtin_func_cast_more_than_one_arg)
+        << R;
+    else
+      S.Diag(Kind.getLocation(), diag::err_excess_initializers)
+        << /*scalar=*/2 << R;
+    break;
+  }
+
+  case FK_ParenthesizedListInitForScalar:
+    S.Diag(Kind.getLocation(), diag::err_list_init_in_parens)
+      << 0 << Entity.getType() << Args[0]->getSourceRange();
+    break;
+
+  case FK_ReferenceBindingToInitList:
+    S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list)
+      << DestType.getNonReferenceType() << Args[0]->getSourceRange();
+    break;
+
+  case FK_InitListBadDestinationType:
+    S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type)
+      << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange();
+    break;
+
+  case FK_ListConstructorOverloadFailed:
+  case FK_ConstructorOverloadFailed: {
+    SourceRange ArgsRange;
+    if (Args.size())
+      ArgsRange =
+          SourceRange(Args.front()->getBeginLoc(), Args.back()->getEndLoc());
+
+    if (Failure == FK_ListConstructorOverloadFailed) {
+      assert(Args.size() == 1 &&
+             "List construction from other than 1 argument.");
+      InitListExpr *InitList = cast<InitListExpr>(Args[0]);
+      Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
+    }
+
+    // FIXME: Using "DestType" for the entity we're printing is probably
+    // bad.
+    switch (FailedOverloadResult) {
+      case OR_Ambiguous:
+        FailedCandidateSet.NoteCandidates(
+            PartialDiagnosticAt(Kind.getLocation(),
+                                S.PDiag(diag::err_ovl_ambiguous_init)
+                                    << DestType << ArgsRange),
+            S, OCD_ViableCandidates, Args);
+        break;
+
+      case OR_No_Viable_Function:
+        if (Kind.getKind() == InitializationKind::IK_Default &&
+            (Entity.getKind() == InitializedEntity::EK_Base ||
+             Entity.getKind() == InitializedEntity::EK_Member) &&
+            isa<CXXConstructorDecl>(S.CurContext)) {
+          // This is implicit default initialization of a member or
+          // base within a constructor. If no viable function was
+          // found, notify the user that they need to explicitly
+          // initialize this base/member.
+          CXXConstructorDecl *Constructor
+            = cast<CXXConstructorDecl>(S.CurContext);
+          const CXXRecordDecl *InheritedFrom = nullptr;
+          if (auto Inherited = Constructor->getInheritedConstructor())
+            InheritedFrom = Inherited.getShadowDecl()->getNominatedBaseClass();
+          if (Entity.getKind() == InitializedEntity::EK_Base) {
+            S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
+              << (InheritedFrom ? 2 : Constructor->isImplicit() ? 1 : 0)
+              << S.Context.getTypeDeclType(Constructor->getParent())
+              << /*base=*/0
+              << Entity.getType()
+              << InheritedFrom;
+
+            RecordDecl *BaseDecl
+              = Entity.getBaseSpecifier()->getType()->getAs<RecordType>()
+                                                                  ->getDecl();
+            S.Diag(BaseDecl->getLocation(), diag::note_previous_decl)
+              << S.Context.getTagDeclType(BaseDecl);
+          } else {
+            S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
+              << (InheritedFrom ? 2 : Constructor->isImplicit() ? 1 : 0)
+              << S.Context.getTypeDeclType(Constructor->getParent())
+              << /*member=*/1
+              << Entity.getName()
+              << InheritedFrom;
+            S.Diag(Entity.getDecl()->getLocation(),
+                   diag::note_member_declared_at);
+
+            if (const RecordType *Record
+                                 = Entity.getType()->getAs<RecordType>())
+              S.Diag(Record->getDecl()->getLocation(),
+                     diag::note_previous_decl)
+                << S.Context.getTagDeclType(Record->getDecl());
+          }
+          break;
+        }
+
+        FailedCandidateSet.NoteCandidates(
+            PartialDiagnosticAt(
+                Kind.getLocation(),
+                S.PDiag(diag::err_ovl_no_viable_function_in_init)
+                    << DestType << ArgsRange),
+            S, OCD_AllCandidates, Args);
+        break;
+
+      case OR_Deleted: {
+        OverloadCandidateSet::iterator Best;
+        OverloadingResult Ovl
+          = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
+        if (Ovl != OR_Deleted) {
+          S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
+              << DestType << ArgsRange;
+          llvm_unreachable("Inconsistent overload resolution?");
+          break;
+        }
+
+        // If this is a defaulted or implicitly-declared function, then
+        // it was implicitly deleted. Make it clear that the deletion was
+        // implicit.
+        if (S.isImplicitlyDeleted(Best->Function))
+          S.Diag(Kind.getLocation(), diag::err_ovl_deleted_special_init)
+            << S.getSpecialMember(cast<CXXMethodDecl>(Best->Function))
+            << DestType << ArgsRange;
+        else
+          S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
+              << DestType << ArgsRange;
+
+        S.NoteDeletedFunction(Best->Function);
+        break;
+      }
+
+      case OR_Success:
+        llvm_unreachable("Conversion did not fail!");
+    }
+  }
+  break;
+
+  case FK_DefaultInitOfConst:
+    if (Entity.getKind() == InitializedEntity::EK_Member &&
+        isa<CXXConstructorDecl>(S.CurContext)) {
+      // This is implicit default-initialization of a const member in
+      // a constructor. Complain that it needs to be explicitly
+      // initialized.
+      CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext);
+      S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor)
+        << (Constructor->getInheritedConstructor() ? 2 :
+            Constructor->isImplicit() ? 1 : 0)
+        << S.Context.getTypeDeclType(Constructor->getParent())
+        << /*const=*/1
+        << Entity.getName();
+      S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl)
+        << Entity.getName();
+    } else {
+      S.Diag(Kind.getLocation(), diag::err_default_init_const)
+          << DestType << (bool)DestType->getAs<RecordType>();
+    }
+    break;
+
+  case FK_Incomplete:
+    S.RequireCompleteType(Kind.getLocation(), FailedIncompleteType,
+                          diag::err_init_incomplete_type);
+    break;
+
+  case FK_ListInitializationFailed: {
+    // Run the init list checker again to emit diagnostics.
+    InitListExpr *InitList = cast<InitListExpr>(Args[0]);
+    diagnoseListInit(S, Entity, InitList);
+    break;
+  }
+
+  case FK_PlaceholderType: {
+    // FIXME: Already diagnosed!
+    break;
+  }
+
+  case FK_ExplicitConstructor: {
+    S.Diag(Kind.getLocation(), diag::err_selected_explicit_constructor)
+      << Args[0]->getSourceRange();
+    OverloadCandidateSet::iterator Best;
+    OverloadingResult Ovl
+      = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
+    (void)Ovl;
+    assert(Ovl == OR_Success && "Inconsistent overload resolution");
+    CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
+    S.Diag(CtorDecl->getLocation(),
+           diag::note_explicit_ctor_deduction_guide_here) << false;
+    break;
+  }
+  }
+
+  PrintInitLocationNote(S, Entity);
+  return true;
+}
+
+void InitializationSequence::dump(raw_ostream &OS) const {
+  switch (SequenceKind) {
+  case FailedSequence: {
+    OS << "Failed sequence: ";
+    switch (Failure) {
+    case FK_TooManyInitsForReference:
+      OS << "too many initializers for reference";
+      break;
+
+    case FK_ParenthesizedListInitForReference:
+      OS << "parenthesized list init for reference";
+      break;
+
+    case FK_ArrayNeedsInitList:
+      OS << "array requires initializer list";
+      break;
+
+    case FK_AddressOfUnaddressableFunction:
+      OS << "address of unaddressable function was taken";
+      break;
+
+    case FK_ArrayNeedsInitListOrStringLiteral:
+      OS << "array requires initializer list or string literal";
+      break;
+
+    case FK_ArrayNeedsInitListOrWideStringLiteral:
+      OS << "array requires initializer list or wide string literal";
+      break;
+
+    case FK_NarrowStringIntoWideCharArray:
+      OS << "narrow string into wide char array";
+      break;
+
+    case FK_WideStringIntoCharArray:
+      OS << "wide string into char array";
+      break;
+
+    case FK_IncompatWideStringIntoWideChar:
+      OS << "incompatible wide string into wide char array";
+      break;
+
+    case FK_PlainStringIntoUTF8Char:
+      OS << "plain string literal into char8_t array";
+      break;
+
+    case FK_UTF8StringIntoPlainChar:
+      OS << "u8 string literal into char array";
+      break;
+
+    case FK_ArrayTypeMismatch:
+      OS << "array type mismatch";
+      break;
+
+    case FK_NonConstantArrayInit:
+      OS << "non-constant array initializer";
+      break;
+
+    case FK_AddressOfOverloadFailed:
+      OS << "address of overloaded function failed";
+      break;
+
+    case FK_ReferenceInitOverloadFailed:
+      OS << "overload resolution for reference initialization failed";
+      break;
+
+    case FK_NonConstLValueReferenceBindingToTemporary:
+      OS << "non-const lvalue reference bound to temporary";
+      break;
+
+    case FK_NonConstLValueReferenceBindingToBitfield:
+      OS << "non-const lvalue reference bound to bit-field";
+      break;
+
+    case FK_NonConstLValueReferenceBindingToVectorElement:
+      OS << "non-const lvalue reference bound to vector element";
+      break;
+
+    case FK_NonConstLValueReferenceBindingToUnrelated:
+      OS << "non-const lvalue reference bound to unrelated type";
+      break;
+
+    case FK_RValueReferenceBindingToLValue:
+      OS << "rvalue reference bound to an lvalue";
+      break;
+
+    case FK_ReferenceInitDropsQualifiers:
+      OS << "reference initialization drops qualifiers";
+      break;
+
+    case FK_ReferenceAddrspaceMismatchTemporary:
+      OS << "reference with mismatching address space bound to temporary";
+      break;
+
+    case FK_ReferenceInitFailed:
+      OS << "reference initialization failed";
+      break;
+
+    case FK_ConversionFailed:
+      OS << "conversion failed";
+      break;
+
+    case FK_ConversionFromPropertyFailed:
+      OS << "conversion from property failed";
+      break;
+
+    case FK_TooManyInitsForScalar:
+      OS << "too many initializers for scalar";
+      break;
+
+    case FK_ParenthesizedListInitForScalar:
+      OS << "parenthesized list init for reference";
+      break;
+
+    case FK_ReferenceBindingToInitList:
+      OS << "referencing binding to initializer list";
+      break;
+
+    case FK_InitListBadDestinationType:
+      OS << "initializer list for non-aggregate, non-scalar type";
+      break;
+
+    case FK_UserConversionOverloadFailed:
+      OS << "overloading failed for user-defined conversion";
+      break;
+
+    case FK_ConstructorOverloadFailed:
+      OS << "constructor overloading failed";
+      break;
+
+    case FK_DefaultInitOfConst:
+      OS << "default initialization of a const variable";
+      break;
+
+    case FK_Incomplete:
+      OS << "initialization of incomplete type";
+      break;
+
+    case FK_ListInitializationFailed:
+      OS << "list initialization checker failure";
+      break;
+
+    case FK_VariableLengthArrayHasInitializer:
+      OS << "variable length array has an initializer";
+      break;
+
+    case FK_PlaceholderType:
+      OS << "initializer expression isn't contextually valid";
+      break;
+
+    case FK_ListConstructorOverloadFailed:
+      OS << "list constructor overloading failed";
+      break;
+
+    case FK_ExplicitConstructor:
+      OS << "list copy initialization chose explicit constructor";
+      break;
+    }
+    OS << '\n';
+    return;
+  }
+
+  case DependentSequence:
+    OS << "Dependent sequence\n";
+    return;
+
+  case NormalSequence:
+    OS << "Normal sequence: ";
+    break;
+  }
+
+  for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) {
+    if (S != step_begin()) {
+      OS << " -> ";
+    }
+
+    switch (S->Kind) {
+    case SK_ResolveAddressOfOverloadedFunction:
+      OS << "resolve address of overloaded function";
+      break;
+
+    case SK_CastDerivedToBaseRValue:
+      OS << "derived-to-base (rvalue)";
+      break;
+
+    case SK_CastDerivedToBaseXValue:
+      OS << "derived-to-base (xvalue)";
+      break;
+
+    case SK_CastDerivedToBaseLValue:
+      OS << "derived-to-base (lvalue)";
+      break;
+
+    case SK_BindReference:
+      OS << "bind reference to lvalue";
+      break;
+
+    case SK_BindReferenceToTemporary:
+      OS << "bind reference to a temporary";
+      break;
+
+    case SK_FinalCopy:
+      OS << "final copy in class direct-initialization";
+      break;
+
+    case SK_ExtraneousCopyToTemporary:
+      OS << "extraneous C++03 copy to temporary";
+      break;
+
+    case SK_UserConversion:
+      OS << "user-defined conversion via " << *S->Function.Function;
+      break;
+
+    case SK_QualificationConversionRValue:
+      OS << "qualification conversion (rvalue)";
+      break;
+
+    case SK_QualificationConversionXValue:
+      OS << "qualification conversion (xvalue)";
+      break;
+
+    case SK_QualificationConversionLValue:
+      OS << "qualification conversion (lvalue)";
+      break;
+
+    case SK_AtomicConversion:
+      OS << "non-atomic-to-atomic conversion";
+      break;
+
+    case SK_ConversionSequence:
+      OS << "implicit conversion sequence (";
+      S->ICS->dump(); // FIXME: use OS
+      OS << ")";
+      break;
+
+    case SK_ConversionSequenceNoNarrowing:
+      OS << "implicit conversion sequence with narrowing prohibited (";
+      S->ICS->dump(); // FIXME: use OS
+      OS << ")";
+      break;
+
+    case SK_ListInitialization:
+      OS << "list aggregate initialization";
+      break;
+
+    case SK_UnwrapInitList:
+      OS << "unwrap reference initializer list";
+      break;
+
+    case SK_RewrapInitList:
+      OS << "rewrap reference initializer list";
+      break;
+
+    case SK_ConstructorInitialization:
+      OS << "constructor initialization";
+      break;
+
+    case SK_ConstructorInitializationFromList:
+      OS << "list initialization via constructor";
+      break;
+
+    case SK_ZeroInitialization:
+      OS << "zero initialization";
+      break;
+
+    case SK_CAssignment:
+      OS << "C assignment";
+      break;
+
+    case SK_StringInit:
+      OS << "string initialization";
+      break;
+
+    case SK_ObjCObjectConversion:
+      OS << "Objective-C object conversion";
+      break;
+
+    case SK_ArrayLoopIndex:
+      OS << "indexing for array initialization loop";
+      break;
+
+    case SK_ArrayLoopInit:
+      OS << "array initialization loop";
+      break;
+
+    case SK_ArrayInit:
+      OS << "array initialization";
+      break;
+
+    case SK_GNUArrayInit:
+      OS << "array initialization (GNU extension)";
+      break;
+
+    case SK_ParenthesizedArrayInit:
+      OS << "parenthesized array initialization";
+      break;
+
+    case SK_PassByIndirectCopyRestore:
+      OS << "pass by indirect copy and restore";
+      break;
+
+    case SK_PassByIndirectRestore:
+      OS << "pass by indirect restore";
+      break;
+
+    case SK_ProduceObjCObject:
+      OS << "Objective-C object retension";
+      break;
+
+    case SK_StdInitializerList:
+      OS << "std::initializer_list from initializer list";
+      break;
+
+    case SK_StdInitializerListConstructorCall:
+      OS << "list initialization from std::initializer_list";
+      break;
+
+    case SK_OCLSamplerInit:
+      OS << "OpenCL sampler_t from integer constant";
+      break;
+
+    case SK_OCLZeroOpaqueType:
+      OS << "OpenCL opaque type from zero";
+      break;
+    }
+
+    OS << " [" << S->Type.getAsString() << ']';
+  }
+
+  OS << '\n';
+}
+
+void InitializationSequence::dump() const {
+  dump(llvm::errs());
+}
+
+static bool NarrowingErrs(const LangOptions &L) {
+  return L.CPlusPlus11 &&
+         (!L.MicrosoftExt || L.isCompatibleWithMSVC(LangOptions::MSVC2015));
+}
+
+static void DiagnoseNarrowingInInitList(Sema &S,
+                                        const ImplicitConversionSequence &ICS,
+                                        QualType PreNarrowingType,
+                                        QualType EntityType,
+                                        const Expr *PostInit) {
+  const StandardConversionSequence *SCS = nullptr;
+  switch (ICS.getKind()) {
+  case ImplicitConversionSequence::StandardConversion:
+    SCS = &ICS.Standard;
+    break;
+  case ImplicitConversionSequence::UserDefinedConversion:
+    SCS = &ICS.UserDefined.After;
+    break;
+  case ImplicitConversionSequence::AmbiguousConversion:
+  case ImplicitConversionSequence::EllipsisConversion:
+  case ImplicitConversionSequence::BadConversion:
+    return;
+  }
+
+  // C++11 [dcl.init.list]p7: Check whether this is a narrowing conversion.
+  APValue ConstantValue;
+  QualType ConstantType;
+  switch (SCS->getNarrowingKind(S.Context, PostInit, ConstantValue,
+                                ConstantType)) {
+  case NK_Not_Narrowing:
+  case NK_Dependent_Narrowing:
+    // No narrowing occurred.
+    return;
+
+  case NK_Type_Narrowing:
+    // This was a floating-to-integer conversion, which is always considered a
+    // narrowing conversion even if the value is a constant and can be
+    // represented exactly as an integer.
+    S.Diag(PostInit->getBeginLoc(), NarrowingErrs(S.getLangOpts())
+                                        ? diag::ext_init_list_type_narrowing
+                                        : diag::warn_init_list_type_narrowing)
+        << PostInit->getSourceRange()
+        << PreNarrowingType.getLocalUnqualifiedType()
+        << EntityType.getLocalUnqualifiedType();
+    break;
+
+  case NK_Constant_Narrowing:
+    // A constant value was narrowed.
+    S.Diag(PostInit->getBeginLoc(),
+           NarrowingErrs(S.getLangOpts())
+               ? diag::ext_init_list_constant_narrowing
+               : diag::warn_init_list_constant_narrowing)
+        << PostInit->getSourceRange()
+        << ConstantValue.getAsString(S.getASTContext(), ConstantType)
+        << EntityType.getLocalUnqualifiedType();
+    break;
+
+  case NK_Variable_Narrowing:
+    // A variable's value may have been narrowed.
+    S.Diag(PostInit->getBeginLoc(),
+           NarrowingErrs(S.getLangOpts())
+               ? diag::ext_init_list_variable_narrowing
+               : diag::warn_init_list_variable_narrowing)
+        << PostInit->getSourceRange()
+        << PreNarrowingType.getLocalUnqualifiedType()
+        << EntityType.getLocalUnqualifiedType();
+    break;
+  }
+
+  SmallString<128> StaticCast;
+  llvm::raw_svector_ostream OS(StaticCast);
+  OS << "static_cast<";
+  if (const TypedefType *TT = EntityType->getAs<TypedefType>()) {
+    // It's important to use the typedef's name if there is one so that the
+    // fixit doesn't break code using types like int64_t.
+    //
+    // FIXME: This will break if the typedef requires qualification.  But
+    // getQualifiedNameAsString() includes non-machine-parsable components.
+    OS << *TT->getDecl();
+  } else if (const BuiltinType *BT = EntityType->getAs<BuiltinType>())
+    OS << BT->getName(S.getLangOpts());
+  else {
+    // Oops, we didn't find the actual type of the variable.  Don't emit a fixit
+    // with a broken cast.
+    return;
+  }
+  OS << ">(";
+  S.Diag(PostInit->getBeginLoc(), diag::note_init_list_narrowing_silence)
+      << PostInit->getSourceRange()
+      << FixItHint::CreateInsertion(PostInit->getBeginLoc(), OS.str())
+      << FixItHint::CreateInsertion(
+             S.getLocForEndOfToken(PostInit->getEndLoc()), ")");
+}
+
+//===----------------------------------------------------------------------===//
+// Initialization helper functions
+//===----------------------------------------------------------------------===//
+bool
+Sema::CanPerformCopyInitialization(const InitializedEntity &Entity,
+                                   ExprResult Init) {
+  if (Init.isInvalid())
+    return false;
+
+  Expr *InitE = Init.get();
+  assert(InitE && "No initialization expression");
+
+  InitializationKind Kind =
+      InitializationKind::CreateCopy(InitE->getBeginLoc(), SourceLocation());
+  InitializationSequence Seq(*this, Entity, Kind, InitE);
+  return !Seq.Failed();
+}
+
+ExprResult
+Sema::PerformCopyInitialization(const InitializedEntity &Entity,
+                                SourceLocation EqualLoc,
+                                ExprResult Init,
+                                bool TopLevelOfInitList,
+                                bool AllowExplicit) {
+  if (Init.isInvalid())
+    return ExprError();
+
+  Expr *InitE = Init.get();
+  assert(InitE && "No initialization expression?");
+
+  if (EqualLoc.isInvalid())
+    EqualLoc = InitE->getBeginLoc();
+
+  InitializationKind Kind = InitializationKind::CreateCopy(
+      InitE->getBeginLoc(), EqualLoc, AllowExplicit);
+  InitializationSequence Seq(*this, Entity, Kind, InitE, TopLevelOfInitList);
+
+  // Prevent infinite recursion when performing parameter copy-initialization.
+  const bool ShouldTrackCopy =
+      Entity.isParameterKind() && Seq.isConstructorInitialization();
+  if (ShouldTrackCopy) {
+    if (llvm::find(CurrentParameterCopyTypes, Entity.getType()) !=
+        CurrentParameterCopyTypes.end()) {
+      Seq.SetOverloadFailure(
+          InitializationSequence::FK_ConstructorOverloadFailed,
+          OR_No_Viable_Function);
+
+      // Try to give a meaningful diagnostic note for the problematic
+      // constructor.
+      const auto LastStep = Seq.step_end() - 1;
+      assert(LastStep->Kind ==
+             InitializationSequence::SK_ConstructorInitialization);
+      const FunctionDecl *Function = LastStep->Function.Function;
+      auto Candidate =
+          llvm::find_if(Seq.getFailedCandidateSet(),
+                        [Function](const OverloadCandidate &Candidate) -> bool {
+                          return Candidate.Viable &&
+                                 Candidate.Function == Function &&
+                                 Candidate.Conversions.size() > 0;
+                        });
+      if (Candidate != Seq.getFailedCandidateSet().end() &&
+          Function->getNumParams() > 0) {
+        Candidate->Viable = false;
+        Candidate->FailureKind = ovl_fail_bad_conversion;
+        Candidate->Conversions[0].setBad(BadConversionSequence::no_conversion,
+                                         InitE,
+                                         Function->getParamDecl(0)->getType());
+      }
+    }
+    CurrentParameterCopyTypes.push_back(Entity.getType());
+  }
+
+  ExprResult Result = Seq.Perform(*this, Entity, Kind, InitE);
+
+  if (ShouldTrackCopy)
+    CurrentParameterCopyTypes.pop_back();
+
+  return Result;
+}
+
+/// Determine whether RD is, or is derived from, a specialization of CTD.
+static bool isOrIsDerivedFromSpecializationOf(CXXRecordDecl *RD,
+                                              ClassTemplateDecl *CTD) {
+  auto NotSpecialization = [&] (const CXXRecordDecl *Candidate) {
+    auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(Candidate);
+    return !CTSD || !declaresSameEntity(CTSD->getSpecializedTemplate(), CTD);
+  };
+  return !(NotSpecialization(RD) && RD->forallBases(NotSpecialization));
+}
+
+QualType Sema::DeduceTemplateSpecializationFromInitializer(
+    TypeSourceInfo *TSInfo, const InitializedEntity &Entity,
+    const InitializationKind &Kind, MultiExprArg Inits) {
+  auto *DeducedTST = dyn_cast<DeducedTemplateSpecializationType>(
+      TSInfo->getType()->getContainedDeducedType());
+  assert(DeducedTST && "not a deduced template specialization type");
+
+  auto TemplateName = DeducedTST->getTemplateName();
+  if (TemplateName.isDependent())
+    return Context.DependentTy;
+
+  // We can only perform deduction for class templates.
+  auto *Template =
+      dyn_cast_or_null<ClassTemplateDecl>(TemplateName.getAsTemplateDecl());
+  if (!Template) {
+    Diag(Kind.getLocation(),
+         diag::err_deduced_non_class_template_specialization_type)
+      << (int)getTemplateNameKindForDiagnostics(TemplateName) << TemplateName;
+    if (auto *TD = TemplateName.getAsTemplateDecl())
+      Diag(TD->getLocation(), diag::note_template_decl_here);
+    return QualType();
+  }
+
+  // Can't deduce from dependent arguments.
+  if (Expr::hasAnyTypeDependentArguments(Inits)) {
+    Diag(TSInfo->getTypeLoc().getBeginLoc(),
+         diag::warn_cxx14_compat_class_template_argument_deduction)
+        << TSInfo->getTypeLoc().getSourceRange() << 0;
+    return Context.DependentTy;
+  }
+
+  // FIXME: Perform "exact type" matching first, per CWG discussion?
+  //        Or implement this via an implied 'T(T) -> T' deduction guide?
+
+  // FIXME: Do we need/want a std::initializer_list<T> special case?
+
+  // Look up deduction guides, including those synthesized from constructors.
+  //
+  // C++1z [over.match.class.deduct]p1:
+  //   A set of functions and function templates is formed comprising:
+  //   - For each constructor of the class template designated by the
+  //     template-name, a function template [...]
+  //  - For each deduction-guide, a function or function template [...]
+  DeclarationNameInfo NameInfo(
+      Context.DeclarationNames.getCXXDeductionGuideName(Template),
+      TSInfo->getTypeLoc().getEndLoc());
+  LookupResult Guides(*this, NameInfo, LookupOrdinaryName);
+  LookupQualifiedName(Guides, Template->getDeclContext());
+
+  // FIXME: Do not diagnose inaccessible deduction guides. The standard isn't
+  // clear on this, but they're not found by name so access does not apply.
+  Guides.suppressDiagnostics();
+
+  // Figure out if this is list-initialization.
+  InitListExpr *ListInit =
+      (Inits.size() == 1 && Kind.getKind() != InitializationKind::IK_Direct)
+          ? dyn_cast<InitListExpr>(Inits[0])
+          : nullptr;
+
+  // C++1z [over.match.class.deduct]p1:
+  //   Initialization and overload resolution are performed as described in
+  //   [dcl.init] and [over.match.ctor], [over.match.copy], or [over.match.list]
+  //   (as appropriate for the type of initialization performed) for an object
+  //   of a hypothetical class type, where the selected functions and function
+  //   templates are considered to be the constructors of that class type
+  //
+  // Since we know we're initializing a class type of a type unrelated to that
+  // of the initializer, this reduces to something fairly reasonable.
+  OverloadCandidateSet Candidates(Kind.getLocation(),
+                                  OverloadCandidateSet::CSK_Normal);
+  OverloadCandidateSet::iterator Best;
+
+  bool HasAnyDeductionGuide = false;
+  bool AllowExplicit = !Kind.isCopyInit() || ListInit;
+
+  auto tryToResolveOverload =
+      [&](bool OnlyListConstructors) -> OverloadingResult {
+    Candidates.clear(OverloadCandidateSet::CSK_Normal);
+    HasAnyDeductionGuide = false;
+
+    for (auto I = Guides.begin(), E = Guides.end(); I != E; ++I) {
+      NamedDecl *D = (*I)->getUnderlyingDecl();
+      if (D->isInvalidDecl())
+        continue;
+
+      auto *TD = dyn_cast<FunctionTemplateDecl>(D);
+      auto *GD = dyn_cast_or_null<CXXDeductionGuideDecl>(
+          TD ? TD->getTemplatedDecl() : dyn_cast<FunctionDecl>(D));
+      if (!GD)
+        continue;
+
+      if (!GD->isImplicit())
+        HasAnyDeductionGuide = true;
+
+      // C++ [over.match.ctor]p1: (non-list copy-initialization from non-class)
+      //   For copy-initialization, the candidate functions are all the
+      //   converting constructors (12.3.1) of that class.
+      // C++ [over.match.copy]p1: (non-list copy-initialization from class)
+      //   The converting constructors of T are candidate functions.
+      if (!AllowExplicit) {
+        // Only consider converting constructors.
+        if (GD->isExplicit())
+          continue;
+
+        // When looking for a converting constructor, deduction guides that
+        // could never be called with one argument are not interesting to
+        // check or note.
+        if (GD->getMinRequiredArguments() > 1 ||
+            (GD->getNumParams() == 0 && !GD->isVariadic()))
+          continue;
+      }
+
+      // C++ [over.match.list]p1.1: (first phase list initialization)
+      //   Initially, the candidate functions are the initializer-list
+      //   constructors of the class T
+      if (OnlyListConstructors && !isInitListConstructor(GD))
+        continue;
+
+      // C++ [over.match.list]p1.2: (second phase list initialization)
+      //   the candidate functions are all the constructors of the class T
+      // C++ [over.match.ctor]p1: (all other cases)
+      //   the candidate functions are all the constructors of the class of
+      //   the object being initialized
+
+      // C++ [over.best.ics]p4:
+      //   When [...] the constructor [...] is a candidate by
+      //    - [over.match.copy] (in all cases)
+      // FIXME: The "second phase of [over.match.list] case can also
+      // theoretically happen here, but it's not clear whether we can
+      // ever have a parameter of the right type.
+      bool SuppressUserConversions = Kind.isCopyInit();
+
+      if (TD)
+        AddTemplateOverloadCandidate(TD, I.getPair(), /*ExplicitArgs*/ nullptr,
+                                     Inits, Candidates, SuppressUserConversions,
+                                     /*PartialOverloading*/ false,
+                                     AllowExplicit);
+      else
+        AddOverloadCandidate(GD, I.getPair(), Inits, Candidates,
+                             SuppressUserConversions,
+                             /*PartialOverloading*/ false, AllowExplicit);
+    }
+    return Candidates.BestViableFunction(*this, Kind.getLocation(), Best);
+  };
+
+  OverloadingResult Result = OR_No_Viable_Function;
+
+  // C++11 [over.match.list]p1, per DR1467: for list-initialization, first
+  // try initializer-list constructors.
+  if (ListInit) {
+    bool TryListConstructors = true;
+
+    // Try list constructors unless the list is empty and the class has one or
+    // more default constructors, in which case those constructors win.
+    if (!ListInit->getNumInits()) {
+      for (NamedDecl *D : Guides) {
+        auto *FD = dyn_cast<FunctionDecl>(D->getUnderlyingDecl());
+        if (FD && FD->getMinRequiredArguments() == 0) {
+          TryListConstructors = false;
+          break;
+        }
+      }
+    } else if (ListInit->getNumInits() == 1) {
+      // C++ [over.match.class.deduct]:
+      //   As an exception, the first phase in [over.match.list] (considering
+      //   initializer-list constructors) is omitted if the initializer list
+      //   consists of a single expression of type cv U, where U is a
+      //   specialization of C or a class derived from a specialization of C.
+      Expr *E = ListInit->getInit(0);
+      auto *RD = E->getType()->getAsCXXRecordDecl();
+      if (!isa<InitListExpr>(E) && RD &&
+          isCompleteType(Kind.getLocation(), E->getType()) &&
+          isOrIsDerivedFromSpecializationOf(RD, Template))
+        TryListConstructors = false;
+    }
+
+    if (TryListConstructors)
+      Result = tryToResolveOverload(/*OnlyListConstructor*/true);
+    // Then unwrap the initializer list and try again considering all
+    // constructors.
+    Inits = MultiExprArg(ListInit->getInits(), ListInit->getNumInits());
+  }
+
+  // If list-initialization fails, or if we're doing any other kind of
+  // initialization, we (eventually) consider constructors.
+  if (Result == OR_No_Viable_Function)
+    Result = tryToResolveOverload(/*OnlyListConstructor*/false);
+
+  switch (Result) {
+  case OR_Ambiguous:
+    // FIXME: For list-initialization candidates, it'd usually be better to
+    // list why they were not viable when given the initializer list itself as
+    // an argument.
+    Candidates.NoteCandidates(
+        PartialDiagnosticAt(
+            Kind.getLocation(),
+            PDiag(diag::err_deduced_class_template_ctor_ambiguous)
+                << TemplateName),
+        *this, OCD_ViableCandidates, Inits);
+    return QualType();
+
+  case OR_No_Viable_Function: {
+    CXXRecordDecl *Primary =
+        cast<ClassTemplateDecl>(Template)->getTemplatedDecl();
+    bool Complete =
+        isCompleteType(Kind.getLocation(), Context.getTypeDeclType(Primary));
+    Candidates.NoteCandidates(
+        PartialDiagnosticAt(
+            Kind.getLocation(),
+            PDiag(Complete ? diag::err_deduced_class_template_ctor_no_viable
+                           : diag::err_deduced_class_template_incomplete)
+                << TemplateName << !Guides.empty()),
+        *this, OCD_AllCandidates, Inits);
+    return QualType();
+  }
+
+  case OR_Deleted: {
+    Diag(Kind.getLocation(), diag::err_deduced_class_template_deleted)
+      << TemplateName;
+    NoteDeletedFunction(Best->Function);
+    return QualType();
+  }
+
+  case OR_Success:
+    // C++ [over.match.list]p1:
+    //   In copy-list-initialization, if an explicit constructor is chosen, the
+    //   initialization is ill-formed.
+    if (Kind.isCopyInit() && ListInit &&
+        cast<CXXDeductionGuideDecl>(Best->Function)->isExplicit()) {
+      bool IsDeductionGuide = !Best->Function->isImplicit();
+      Diag(Kind.getLocation(), diag::err_deduced_class_template_explicit)
+          << TemplateName << IsDeductionGuide;
+      Diag(Best->Function->getLocation(),
+           diag::note_explicit_ctor_deduction_guide_here)
+          << IsDeductionGuide;
+      return QualType();
+    }
+
+    // Make sure we didn't select an unusable deduction guide, and mark it
+    // as referenced.
+    DiagnoseUseOfDecl(Best->Function, Kind.getLocation());
+    MarkFunctionReferenced(Kind.getLocation(), Best->Function);
+    break;
+  }
+
+  // C++ [dcl.type.class.deduct]p1:
+  //  The placeholder is replaced by the return type of the function selected
+  //  by overload resolution for class template deduction.
+  QualType DeducedType =
+      SubstAutoType(TSInfo->getType(), Best->Function->getReturnType());
+  Diag(TSInfo->getTypeLoc().getBeginLoc(),
+       diag::warn_cxx14_compat_class_template_argument_deduction)
+      << TSInfo->getTypeLoc().getSourceRange() << 1 << DeducedType;
+
+  // Warn if CTAD was used on a type that does not have any user-defined
+  // deduction guides.
+  if (!HasAnyDeductionGuide) {
+    Diag(TSInfo->getTypeLoc().getBeginLoc(),
+         diag::warn_ctad_maybe_unsupported)
+        << TemplateName;
+    Diag(Template->getLocation(), diag::note_suppress_ctad_maybe_unsupported);
+  }
+
+  return DeducedType;
+}