/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp

Bug Summary

File:	clang/lib/Sema/SemaCast.cpp
Warning:	line 1260, column 14 Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaCast.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-12/lib/clang/12.0.0 -D CLANG_VENDOR="Debian " -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema -I /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include -I /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/build-llvm/include -I /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-12/lib/clang/12.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2020-09-26-161721-17566-1 -x c++ /build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp

/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp

→

1//===--- SemaCast.cpp - Semantic Analysis for Casts -----------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9//  This file implements semantic analysis for cast expressions, including
10//  1) C-style casts like '(int) x'
11//  2) C++ functional casts like 'int(x)'
12//  3) C++ named casts like 'static_cast<int>(x)'
13//
14//===----------------------------------------------------------------------===//

16#include "clang/Sema/SemaInternal.h"
17#include "clang/AST/ASTContext.h"
18#include "clang/AST/CXXInheritance.h"
19#include "clang/AST/ExprCXX.h"
20#include "clang/AST/ExprObjC.h"
21#include "clang/AST/RecordLayout.h"
22#include "clang/Basic/PartialDiagnostic.h"
23#include "clang/Basic/TargetInfo.h"
24#include "clang/Lex/Preprocessor.h"
25#include "clang/Sema/Initialization.h"
26#include "llvm/ADT/SmallVector.h"
27#include <set>
28using namespace clang;



32enum TryCastResult {
TC_NotApplicable, ///< The cast method is not applicable.
TC_Success,       ///< The cast method is appropriate and successful.
TC_Extension,     ///< The cast method is appropriate and accepted as a
                  ///< language extension.
TC_Failed         ///< The cast method is appropriate, but failed. A
                  ///< diagnostic has been emitted.
39};

41static bool isValidCast(TryCastResult TCR) {
return TCR == TC_Success || TCR == TC_Extension;
43}

45enum CastType {
CT_Const,       ///< const_cast
CT_Static,      ///< static_cast
CT_Reinterpret, ///< reinterpret_cast
CT_Dynamic,     ///< dynamic_cast
CT_CStyle,      ///< (Type)expr
CT_Functional,  ///< Type(expr)
CT_Addrspace    ///< addrspace_cast
53};

55namespace {
struct CastOperation {
  CastOperation(Sema &S, QualType destType, ExprResult src)
    : Self(S), SrcExpr(src), DestType(destType),
      ResultType(destType.getNonLValueExprType(S.Context)),
      ValueKind(Expr::getValueKindForType(destType)),
      Kind(CK_Dependent), IsARCUnbridgedCast(false) {

    if (const BuiltinType *placeholder =
          src.get()->getType()->getAsPlaceholderType()) {
      PlaceholderKind = placeholder->getKind();
    } else {
      PlaceholderKind = (BuiltinType::Kind) 0;
    }
  }

  Sema &Self;
  ExprResult SrcExpr;
  QualType DestType;
  QualType ResultType;
  ExprValueKind ValueKind;
  CastKind Kind;
  BuiltinType::Kind PlaceholderKind;
  CXXCastPath BasePath;
  bool IsARCUnbridgedCast;

  SourceRange OpRange;
  SourceRange DestRange;

  // Top-level semantics-checking routines.
  void CheckConstCast();
  void CheckReinterpretCast();
  void CheckStaticCast();
  void CheckDynamicCast();
  void CheckCXXCStyleCast(bool FunctionalCast, bool ListInitialization);
  void CheckCStyleCast();
  void CheckBuiltinBitCast();
  void CheckAddrspaceCast();

  void updatePartOfExplicitCastFlags(CastExpr *CE) {
    // Walk down from the CE to the OrigSrcExpr, and mark all immediate
    // ImplicitCastExpr's as being part of ExplicitCastExpr. The original CE
    // (which is a ExplicitCastExpr), and the OrigSrcExpr are not touched.
    for (; auto *ICE = dyn_cast<ImplicitCastExpr>(CE->getSubExpr()); CE = ICE)
      ICE->setIsPartOfExplicitCast(true);
  }

  /// Complete an apparently-successful cast operation that yields
  /// the given expression.
  ExprResult complete(CastExpr *castExpr) {
    // If this is an unbridged cast, wrap the result in an implicit
    // cast that yields the unbridged-cast placeholder type.
    if (IsARCUnbridgedCast) {
      castExpr = ImplicitCastExpr::Create(
          Self.Context, Self.Context.ARCUnbridgedCastTy, CK_Dependent,
          castExpr, nullptr, castExpr->getValueKind(),
          Self.CurFPFeatureOverrides());
    }
    updatePartOfExplicitCastFlags(castExpr);
    return castExpr;
  }

  // Internal convenience methods.

  /// Try to handle the given placeholder expression kind.  Return
  /// true if the source expression has the appropriate placeholder
  /// kind.  A placeholder can only be claimed once.
  bool claimPlaceholder(BuiltinType::Kind K) {
    if (PlaceholderKind != K) return false;

    PlaceholderKind = (BuiltinType::Kind) 0;
    return true;
  }

  bool isPlaceholder() const {
    return PlaceholderKind != 0;
  }
  bool isPlaceholder(BuiltinType::Kind K) const {
    return PlaceholderKind == K;
  }

  // Language specific cast restrictions for address spaces.
  void checkAddressSpaceCast(QualType SrcType, QualType DestType);

  void checkCastAlign() {
    Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange);
  }

  void checkObjCConversion(Sema::CheckedConversionKind CCK) {
    assert(Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())((Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers()
) ? static_cast<void> (0) : __assert_fail ("Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers()"
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 144, __PRETTY_FUNCTION__));

    Expr *src = SrcExpr.get();
    if (Self.CheckObjCConversion(OpRange, DestType, src, CCK) ==
        Sema::ACR_unbridged)
      IsARCUnbridgedCast = true;
    SrcExpr = src;
  }

  /// Check for and handle non-overload placeholder expressions.
  void checkNonOverloadPlaceholders() {
    if (!isPlaceholder() || isPlaceholder(BuiltinType::Overload))
      return;

    SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
    if (SrcExpr.isInvalid())
      return;
    PlaceholderKind = (BuiltinType::Kind) 0;
  }
};

void CheckNoDeref(Sema &S, const QualType FromType, const QualType ToType,
                  SourceLocation OpLoc) {
  if (const auto *PtrType = dyn_cast<PointerType>(FromType)) {
    if (PtrType->getPointeeType()->hasAttr(attr::NoDeref)) {
      if (const auto *DestType = dyn_cast<PointerType>(ToType)) {
        if (!DestType->getPointeeType()->hasAttr(attr::NoDeref)) {
          S.Diag(OpLoc, diag::warn_noderef_to_dereferenceable_pointer);
        }
      }
    }
  }
}

struct CheckNoDerefRAII {
  CheckNoDerefRAII(CastOperation &Op) : Op(Op) {}
  ~CheckNoDerefRAII() {
    if (!Op.SrcExpr.isInvalid())
      CheckNoDeref(Op.Self, Op.SrcExpr.get()->getType(), Op.ResultType,
                   Op.OpRange.getBegin());
  }

  CastOperation &Op;
};
188}

190static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
                           QualType DestType);

193// The Try functions attempt a specific way of casting. If they succeed, they
194// return TC_Success. If their way of casting is not appropriate for the given
195// arguments, they return TC_NotApplicable and *may* set diag to a diagnostic
196// to emit if no other way succeeds. If their way of casting is appropriate but
197// fails, they return TC_Failed and *must* set diag; they can set it to 0 if
198// they emit a specialized diagnostic.
199// All diagnostics returned by these functions must expect the same three
200// arguments:
201// %0: Cast Type (a value from the CastType enumeration)
202// %1: Source Type
203// %2: Destination Type
204static TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
                                         QualType DestType, bool CStyle,
                                         CastKind &Kind,
                                         CXXCastPath &BasePath,
                                         unsigned &msg);
209static TryCastResult TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr,
                                             QualType DestType, bool CStyle,
                                             SourceRange OpRange,
                                             unsigned &msg,
                                             CastKind &Kind,
                                             CXXCastPath &BasePath);
215static TryCastResult TryStaticPointerDowncast(Sema &Self, QualType SrcType,
                                            QualType DestType, bool CStyle,
                                            SourceRange OpRange,
                                            unsigned &msg,
                                            CastKind &Kind,
                                            CXXCastPath &BasePath);
221static TryCastResult TryStaticDowncast(Sema &Self, CanQualType SrcType,
                                     CanQualType DestType, bool CStyle,
                                     SourceRange OpRange,
                                     QualType OrigSrcType,
                                     QualType OrigDestType, unsigned &msg,
                                     CastKind &Kind,
                                     CXXCastPath &BasePath);
228static TryCastResult TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr,
                                             QualType SrcType,
                                             QualType DestType,bool CStyle,
                                             SourceRange OpRange,
                                             unsigned &msg,
                                             CastKind &Kind,
                                             CXXCastPath &BasePath);

236static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr,
                                         QualType DestType,
                                         Sema::CheckedConversionKind CCK,
                                         SourceRange OpRange,
                                         unsigned &msg, CastKind &Kind,
                                         bool ListInitialization);
242static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
                                 QualType DestType,
                                 Sema::CheckedConversionKind CCK,
                                 SourceRange OpRange,
                                 unsigned &msg, CastKind &Kind,
                                 CXXCastPath &BasePath,
                                 bool ListInitialization);
249static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
                                QualType DestType, bool CStyle,
                                unsigned &msg);
252static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
                                      QualType DestType, bool CStyle,
                                      SourceRange OpRange, unsigned &msg,
                                      CastKind &Kind);
256static TryCastResult TryAddressSpaceCast(Sema &Self, ExprResult &SrcExpr,
                                       QualType DestType, bool CStyle,
                                       unsigned &msg, CastKind &Kind);

260/// ActOnCXXNamedCast - Parse
261/// {dynamic,static,reinterpret,const,addrspace}_cast's.
262ExprResult
263Sema::ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
                      SourceLocation LAngleBracketLoc, Declarator &D,
                      SourceLocation RAngleBracketLoc,
                      SourceLocation LParenLoc, Expr *E,
                      SourceLocation RParenLoc) {

assert(!D.isInvalidType())((!D.isInvalidType()) ? static_cast<void> (0) : __assert_fail
 ("!D.isInvalidType()", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 269, __PRETTY_FUNCTION__));
1
'?' condition is true→

TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, E->getType());
if (D.isInvalidType())
2
←
Taking false branch→
  return ExprError();

if (getLangOpts().CPlusPlus) {
3
←
Assuming field 'CPlusPlus' is 0→
4
←
Taking false branch→
  // Check that there are no default arguments (C++ only).
  CheckExtraCXXDefaultArguments(D);
}

return BuildCXXNamedCast(OpLoc, Kind, TInfo, E,
5
←
Calling 'Sema::BuildCXXNamedCast'→
                         SourceRange(LAngleBracketLoc, RAngleBracketLoc),
                         SourceRange(LParenLoc, RParenLoc));
283}

285ExprResult
286Sema::BuildCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
                      TypeSourceInfo *DestTInfo, Expr *E,
                      SourceRange AngleBrackets, SourceRange Parens) {
ExprResult Ex = E;
QualType DestType = DestTInfo->getType();

// If the type is dependent, we won't do the semantic analysis now.
bool TypeDependent =
    DestType->isDependentType() || Ex.get()->isTypeDependent();
6
←
Assuming the condition is false→

CastOperation Op(*this, DestType, E);
Op.OpRange = SourceRange(OpLoc, Parens.getEnd());
Op.DestRange = AngleBrackets;

switch (Kind) {
7
←
Control jumps to 'case kw_static_cast:'  at line 356→
default: llvm_unreachable("Unknown C++ cast!")::llvm::llvm_unreachable_internal("Unknown C++ cast!", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 301);

case tok::kw_addrspace_cast:
  if (!TypeDependent) {
    Op.CheckAddrspaceCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
  }
  return Op.complete(CXXAddrspaceCastExpr::Create(
      Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
      DestTInfo, OpLoc, Parens.getEnd(), AngleBrackets));

case tok::kw_const_cast:
  if (!TypeDependent) {
    Op.CheckConstCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
    DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
  }
  return Op.complete(CXXConstCastExpr::Create(Context, Op.ResultType,
                                Op.ValueKind, Op.SrcExpr.get(), DestTInfo,
                                              OpLoc, Parens.getEnd(),
                                              AngleBrackets));

case tok::kw_dynamic_cast: {
  // dynamic_cast is not supported in C++ for OpenCL.
  if (getLangOpts().OpenCLCPlusPlus) {
    return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
                     << "dynamic_cast");
  }

  if (!TypeDependent) {
    Op.CheckDynamicCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
  }
  return Op.complete(CXXDynamicCastExpr::Create(Context, Op.ResultType,
                                  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
                                                &Op.BasePath, DestTInfo,
                                                OpLoc, Parens.getEnd(),
                                                AngleBrackets));
}
case tok::kw_reinterpret_cast: {
  if (!TypeDependent) {
    Op.CheckReinterpretCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
    DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
  }
  return Op.complete(CXXReinterpretCastExpr::Create(Context, Op.ResultType,
                                  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
                                                    nullptr, DestTInfo, OpLoc,
                                                    Parens.getEnd(),
                                                    AngleBrackets));
}
case tok::kw_static_cast: {
  if (!TypeDependent) {
8
←
Assuming 'TypeDependent' is false→
9
←
Taking true branch→
    Op.CheckStaticCast();
10
←
Calling 'CastOperation::CheckStaticCast'→
    if (Op.SrcExpr.isInvalid())
      return ExprError();
    DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
  }

  return Op.complete(CXXStaticCastExpr::Create(
      Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
      &Op.BasePath, DestTInfo, CurFPFeatureOverrides(), OpLoc,
      Parens.getEnd(), AngleBrackets));
}
}
370}

372ExprResult Sema::ActOnBuiltinBitCastExpr(SourceLocation KWLoc, Declarator &D,
                                       ExprResult Operand,
                                       SourceLocation RParenLoc) {
assert(!D.isInvalidType())((!D.isInvalidType()) ? static_cast<void> (0) : __assert_fail
 ("!D.isInvalidType()", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 375, __PRETTY_FUNCTION__));

TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, Operand.get()->getType());
if (D.isInvalidType())
  return ExprError();

return BuildBuiltinBitCastExpr(KWLoc, TInfo, Operand.get(), RParenLoc);
382}

384ExprResult Sema::BuildBuiltinBitCastExpr(SourceLocation KWLoc,
                                       TypeSourceInfo *TSI, Expr *Operand,
                                       SourceLocation RParenLoc) {
CastOperation Op(*this, TSI->getType(), Operand);
Op.OpRange = SourceRange(KWLoc, RParenLoc);
TypeLoc TL = TSI->getTypeLoc();
Op.DestRange = SourceRange(TL.getBeginLoc(), TL.getEndLoc());

if (!Operand->isTypeDependent() && !TSI->getType()->isDependentType()) {
  Op.CheckBuiltinBitCast();
  if (Op.SrcExpr.isInvalid())
    return ExprError();
}

BuiltinBitCastExpr *BCE =
    new (Context) BuiltinBitCastExpr(Op.ResultType, Op.ValueKind, Op.Kind,
                                     Op.SrcExpr.get(), TSI, KWLoc, RParenLoc);
return Op.complete(BCE);
402}

404/// Try to diagnose a failed overloaded cast.  Returns true if
405/// diagnostics were emitted.
406static bool tryDiagnoseOverloadedCast(Sema &S, CastType CT,
                                    SourceRange range, Expr *src,
                                    QualType destType,
                                    bool listInitialization) {
switch (CT) {
// These cast kinds don't consider user-defined conversions.
case CT_Const:
case CT_Reinterpret:
case CT_Dynamic:
case CT_Addrspace:
  return false;

// These do.
case CT_Static:
case CT_CStyle:
case CT_Functional:
  break;
}

QualType srcType = src->getType();
if (!destType->isRecordType() && !srcType->isRecordType())
  return false;

InitializedEntity entity = InitializedEntity::InitializeTemporary(destType);
InitializationKind initKind
  = (CT == CT_CStyle)? InitializationKind::CreateCStyleCast(range.getBegin(),
                                                    range, listInitialization)
  : (CT == CT_Functional)? InitializationKind::CreateFunctionalCast(range,
                                                           listInitialization)
  : InitializationKind::CreateCast(/*type range?*/ range);
InitializationSequence sequence(S, entity, initKind, src);

assert(sequence.Failed() && "initialization succeeded on second try?")((sequence.Failed() && "initialization succeeded on second try?"
) ? static_cast<void> (0) : __assert_fail ("sequence.Failed() && \"initialization succeeded on second try?\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 438, __PRETTY_FUNCTION__));
switch (sequence.getFailureKind()) {
default: return false;

case InitializationSequence::FK_ConstructorOverloadFailed:
case InitializationSequence::FK_UserConversionOverloadFailed:
  break;
}

OverloadCandidateSet &candidates = sequence.getFailedCandidateSet();

unsigned msg = 0;
OverloadCandidateDisplayKind howManyCandidates = OCD_AllCandidates;

switch (sequence.getFailedOverloadResult()) {
case OR_Success: llvm_unreachable("successful failed overload")::llvm::llvm_unreachable_internal("successful failed overload"
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 453);
case OR_No_Viable_Function:
  if (candidates.empty())
    msg = diag::err_ovl_no_conversion_in_cast;
  else
    msg = diag::err_ovl_no_viable_conversion_in_cast;
  howManyCandidates = OCD_AllCandidates;
  break;

case OR_Ambiguous:
  msg = diag::err_ovl_ambiguous_conversion_in_cast;
  howManyCandidates = OCD_AmbiguousCandidates;
  break;

case OR_Deleted:
  msg = diag::err_ovl_deleted_conversion_in_cast;
  howManyCandidates = OCD_ViableCandidates;
  break;
}

candidates.NoteCandidates(
    PartialDiagnosticAt(range.getBegin(),
                        S.PDiag(msg) << CT << srcType << destType << range
                                     << src->getSourceRange()),
    S, howManyCandidates, src);

return true;
480}

482/// Diagnose a failed cast.
483static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType,
                          SourceRange opRange, Expr *src, QualType destType,
                          bool listInitialization) {
if (msg == diag::err_bad_cxx_cast_generic &&
    tryDiagnoseOverloadedCast(S, castType, opRange, src, destType,
                              listInitialization))
  return;

S.Diag(opRange.getBegin(), msg) << castType
  << src->getType() << destType << opRange << src->getSourceRange();

// Detect if both types are (ptr to) class, and note any incompleteness.
int DifferentPtrness = 0;
QualType From = destType;
if (auto Ptr = From->getAs<PointerType>()) {
  From = Ptr->getPointeeType();
  DifferentPtrness++;
}
QualType To = src->getType();
if (auto Ptr = To->getAs<PointerType>()) {
  To = Ptr->getPointeeType();
  DifferentPtrness--;
}
if (!DifferentPtrness) {
  auto RecFrom = From->getAs<RecordType>();
  auto RecTo = To->getAs<RecordType>();
  if (RecFrom && RecTo) {
    auto DeclFrom = RecFrom->getAsCXXRecordDecl();
    if (!DeclFrom->isCompleteDefinition())
      S.Diag(DeclFrom->getLocation(), diag::note_type_incomplete) << DeclFrom;
    auto DeclTo = RecTo->getAsCXXRecordDecl();
    if (!DeclTo->isCompleteDefinition())
      S.Diag(DeclTo->getLocation(), diag::note_type_incomplete) << DeclTo;
  }
}
518}

520namespace {
521/// The kind of unwrapping we did when determining whether a conversion casts
522/// away constness.
523enum CastAwayConstnessKind {
/// The conversion does not cast away constness.
CACK_None = 0,
/// We unwrapped similar types.
CACK_Similar = 1,
/// We unwrapped dissimilar types with similar representations (eg, a pointer
/// versus an Objective-C object pointer).
CACK_SimilarKind = 2,
/// We unwrapped representationally-unrelated types, such as a pointer versus
/// a pointer-to-member.
CACK_Incoherent = 3,
534};
535}

537/// Unwrap one level of types for CastsAwayConstness.
538///
539/// Like Sema::UnwrapSimilarTypes, this removes one level of indirection from
540/// both types, provided that they're both pointer-like or array-like. Unlike
541/// the Sema function, doesn't care if the unwrapped pieces are related.
542///
543/// This function may remove additional levels as necessary for correctness:
544/// the resulting T1 is unwrapped sufficiently that it is never an array type,
545/// so that its qualifiers can be directly compared to those of T2 (which will
546/// have the combined set of qualifiers from all indermediate levels of T2),
547/// as (effectively) required by [expr.const.cast]p7 replacing T1's qualifiers
548/// with those from T2.
549static CastAwayConstnessKind
550unwrapCastAwayConstnessLevel(ASTContext &Context, QualType &T1, QualType &T2) {
enum { None, Ptr, MemPtr, BlockPtr, Array };
auto Classify = [](QualType T) {
  if (T->isAnyPointerType()) return Ptr;
  if (T->isMemberPointerType()) return MemPtr;
  if (T->isBlockPointerType()) return BlockPtr;
  // We somewhat-arbitrarily don't look through VLA types here. This is at
  // least consistent with the behavior of UnwrapSimilarTypes.
  if (T->isConstantArrayType() || T->isIncompleteArrayType()) return Array;
  return None;
};

auto Unwrap = [&](QualType T) {
  if (auto *AT = Context.getAsArrayType(T))
    return AT->getElementType();
  return T->getPointeeType();
};

CastAwayConstnessKind Kind;

if (T2->isReferenceType()) {
  // Special case: if the destination type is a reference type, unwrap it as
  // the first level. (The source will have been an lvalue expression in this
  // case, so there is no corresponding "reference to" in T1 to remove.) This
  // simulates removing a "pointer to" from both sides.
  T2 = T2->getPointeeType();
  Kind = CastAwayConstnessKind::CACK_Similar;
} else if (Context.UnwrapSimilarTypes(T1, T2)) {
  Kind = CastAwayConstnessKind::CACK_Similar;
} else {
  // Try unwrapping mismatching levels.
  int T1Class = Classify(T1);
  if (T1Class == None)
    return CastAwayConstnessKind::CACK_None;

  int T2Class = Classify(T2);
  if (T2Class == None)
    return CastAwayConstnessKind::CACK_None;

  T1 = Unwrap(T1);
  T2 = Unwrap(T2);
  Kind = T1Class == T2Class ? CastAwayConstnessKind::CACK_SimilarKind
                            : CastAwayConstnessKind::CACK_Incoherent;
}

// We've unwrapped at least one level. If the resulting T1 is a (possibly
// multidimensional) array type, any qualifier on any matching layer of
// T2 is considered to correspond to T1. Decompose down to the element
// type of T1 so that we can compare properly.
while (true) {
  Context.UnwrapSimilarArrayTypes(T1, T2);

  if (Classify(T1) != Array)
    break;

  auto T2Class = Classify(T2);
  if (T2Class == None)
    break;

  if (T2Class != Array)
    Kind = CastAwayConstnessKind::CACK_Incoherent;
  else if (Kind != CastAwayConstnessKind::CACK_Incoherent)
    Kind = CastAwayConstnessKind::CACK_SimilarKind;

  T1 = Unwrap(T1);
  T2 = Unwrap(T2).withCVRQualifiers(T2.getCVRQualifiers());
}

return Kind;
619}

621/// Check if the pointer conversion from SrcType to DestType casts away
622/// constness as defined in C++ [expr.const.cast]. This is used by the cast
623/// checkers. Both arguments must denote pointer (possibly to member) types.
624///
625/// \param CheckCVR Whether to check for const/volatile/restrict qualifiers.
626/// \param CheckObjCLifetime Whether to check Objective-C lifetime qualifiers.
627static CastAwayConstnessKind
628CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType,
                 bool CheckCVR, bool CheckObjCLifetime,
                 QualType *TheOffendingSrcType = nullptr,
                 QualType *TheOffendingDestType = nullptr,
                 Qualifiers *CastAwayQualifiers = nullptr) {
// If the only checking we care about is for Objective-C lifetime qualifiers,
// and we're not in ObjC mode, there's nothing to check.
if (!CheckCVR && CheckObjCLifetime && !Self.Context.getLangOpts().ObjC)
  return CastAwayConstnessKind::CACK_None;

if (!DestType->isReferenceType()) {
  assert((SrcType->isAnyPointerType() || SrcType->isMemberPointerType() ||(((SrcType->isAnyPointerType() || SrcType->isMemberPointerType
() || SrcType->isBlockPointerType()) && "Source type is not pointer or pointer to member."
) ? static_cast<void> (0) : __assert_fail ("(SrcType->isAnyPointerType() || SrcType->isMemberPointerType() || SrcType->isBlockPointerType()) && \"Source type is not pointer or pointer to member.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 641, __PRETTY_FUNCTION__))
          SrcType->isBlockPointerType()) &&(((SrcType->isAnyPointerType() || SrcType->isMemberPointerType
() || SrcType->isBlockPointerType()) && "Source type is not pointer or pointer to member."
) ? static_cast<void> (0) : __assert_fail ("(SrcType->isAnyPointerType() || SrcType->isMemberPointerType() || SrcType->isBlockPointerType()) && \"Source type is not pointer or pointer to member.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 641, __PRETTY_FUNCTION__))
         "Source type is not pointer or pointer to member.")(((SrcType->isAnyPointerType() || SrcType->isMemberPointerType
() || SrcType->isBlockPointerType()) && "Source type is not pointer or pointer to member."
) ? static_cast<void> (0) : __assert_fail ("(SrcType->isAnyPointerType() || SrcType->isMemberPointerType() || SrcType->isBlockPointerType()) && \"Source type is not pointer or pointer to member.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 641, __PRETTY_FUNCTION__));
  assert((DestType->isAnyPointerType() || DestType->isMemberPointerType() ||(((DestType->isAnyPointerType() || DestType->isMemberPointerType
() || DestType->isBlockPointerType()) && "Destination type is not pointer or pointer to member."
) ? static_cast<void> (0) : __assert_fail ("(DestType->isAnyPointerType() || DestType->isMemberPointerType() || DestType->isBlockPointerType()) && \"Destination type is not pointer or pointer to member.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 644, __PRETTY_FUNCTION__))
          DestType->isBlockPointerType()) &&(((DestType->isAnyPointerType() || DestType->isMemberPointerType
() || DestType->isBlockPointerType()) && "Destination type is not pointer or pointer to member."
) ? static_cast<void> (0) : __assert_fail ("(DestType->isAnyPointerType() || DestType->isMemberPointerType() || DestType->isBlockPointerType()) && \"Destination type is not pointer or pointer to member.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 644, __PRETTY_FUNCTION__))
         "Destination type is not pointer or pointer to member.")(((DestType->isAnyPointerType() || DestType->isMemberPointerType
() || DestType->isBlockPointerType()) && "Destination type is not pointer or pointer to member."
) ? static_cast<void> (0) : __assert_fail ("(DestType->isAnyPointerType() || DestType->isMemberPointerType() || DestType->isBlockPointerType()) && \"Destination type is not pointer or pointer to member.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 644, __PRETTY_FUNCTION__));
}

QualType UnwrappedSrcType = Self.Context.getCanonicalType(SrcType),
         UnwrappedDestType = Self.Context.getCanonicalType(DestType);

// Find the qualifiers. We only care about cvr-qualifiers for the
// purpose of this check, because other qualifiers (address spaces,
// Objective-C GC, etc.) are part of the type's identity.
QualType PrevUnwrappedSrcType = UnwrappedSrcType;
QualType PrevUnwrappedDestType = UnwrappedDestType;
auto WorstKind = CastAwayConstnessKind::CACK_Similar;
bool AllConstSoFar = true;
while (auto Kind = unwrapCastAwayConstnessLevel(
           Self.Context, UnwrappedSrcType, UnwrappedDestType)) {
  // Track the worst kind of unwrap we needed to do before we found a
  // problem.
  if (Kind > WorstKind)
    WorstKind = Kind;

  // Determine the relevant qualifiers at this level.
  Qualifiers SrcQuals, DestQuals;
  Self.Context.getUnqualifiedArrayType(UnwrappedSrcType, SrcQuals);
  Self.Context.getUnqualifiedArrayType(UnwrappedDestType, DestQuals);

  // We do not meaningfully track object const-ness of Objective-C object
  // types. Remove const from the source type if either the source or
  // the destination is an Objective-C object type.
  if (UnwrappedSrcType->isObjCObjectType() ||
      UnwrappedDestType->isObjCObjectType())
    SrcQuals.removeConst();

  if (CheckCVR) {
    Qualifiers SrcCvrQuals =
        Qualifiers::fromCVRMask(SrcQuals.getCVRQualifiers());
    Qualifiers DestCvrQuals =
        Qualifiers::fromCVRMask(DestQuals.getCVRQualifiers());

    if (SrcCvrQuals != DestCvrQuals) {
      if (CastAwayQualifiers)
        *CastAwayQualifiers = SrcCvrQuals - DestCvrQuals;

      // If we removed a cvr-qualifier, this is casting away 'constness'.
      if (!DestCvrQuals.compatiblyIncludes(SrcCvrQuals)) {
        if (TheOffendingSrcType)
          *TheOffendingSrcType = PrevUnwrappedSrcType;
        if (TheOffendingDestType)
          *TheOffendingDestType = PrevUnwrappedDestType;
        return WorstKind;
      }

      // If any prior level was not 'const', this is also casting away
      // 'constness'. We noted the outermost type missing a 'const' already.
      if (!AllConstSoFar)
        return WorstKind;
    }
  }

  if (CheckObjCLifetime &&
      !DestQuals.compatiblyIncludesObjCLifetime(SrcQuals))
    return WorstKind;

  // If we found our first non-const-qualified type, this may be the place
  // where things start to go wrong.
  if (AllConstSoFar && !DestQuals.hasConst()) {
    AllConstSoFar = false;
    if (TheOffendingSrcType)
      *TheOffendingSrcType = PrevUnwrappedSrcType;
    if (TheOffendingDestType)
      *TheOffendingDestType = PrevUnwrappedDestType;
  }

  PrevUnwrappedSrcType = UnwrappedSrcType;
  PrevUnwrappedDestType = UnwrappedDestType;
}

return CastAwayConstnessKind::CACK_None;
721}

723static TryCastResult getCastAwayConstnessCastKind(CastAwayConstnessKind CACK,
                                                unsigned &DiagID) {
switch (CACK) {
case CastAwayConstnessKind::CACK_None:
  llvm_unreachable("did not cast away constness")::llvm::llvm_unreachable_internal("did not cast away constness"
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 727);

case CastAwayConstnessKind::CACK_Similar:
  // FIXME: Accept these as an extension too?
case CastAwayConstnessKind::CACK_SimilarKind:
  DiagID = diag::err_bad_cxx_cast_qualifiers_away;
  return TC_Failed;

case CastAwayConstnessKind::CACK_Incoherent:
  DiagID = diag::ext_bad_cxx_cast_qualifiers_away_incoherent;
  return TC_Extension;
}

llvm_unreachable("unexpected cast away constness kind")::llvm::llvm_unreachable_internal("unexpected cast away constness kind"
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 740);
741}

743/// CheckDynamicCast - Check that a dynamic_cast\<DestType\>(SrcExpr) is valid.
744/// Refer to C++ 5.2.7 for details. Dynamic casts are used mostly for runtime-
745/// checked downcasts in class hierarchies.
746void CastOperation::CheckDynamicCast() {
CheckNoDerefRAII NoderefCheck(*this);

if (ValueKind == VK_RValue)
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
else if (isPlaceholder())
  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
  return;

QualType OrigSrcType = SrcExpr.get()->getType();
QualType DestType = Self.Context.getCanonicalType(this->DestType);

// C++ 5.2.7p1: T shall be a pointer or reference to a complete class type,
//   or "pointer to cv void".

QualType DestPointee;
const PointerType *DestPointer = DestType->getAs<PointerType>();
const ReferenceType *DestReference = nullptr;
if (DestPointer) {
  DestPointee = DestPointer->getPointeeType();
} else if ((DestReference = DestType->getAs<ReferenceType>())) {
  DestPointee = DestReference->getPointeeType();
} else {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ref_or_ptr)
    << this->DestType << DestRange;
  SrcExpr = ExprError();
  return;
}

const RecordType *DestRecord = DestPointee->getAs<RecordType>();
if (DestPointee->isVoidType()) {
  assert(DestPointer && "Reference to void is not possible")((DestPointer && "Reference to void is not possible")
 ? static_cast<void> (0) : __assert_fail ("DestPointer && \"Reference to void is not possible\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 778, __PRETTY_FUNCTION__));
} else if (DestRecord) {
  if (Self.RequireCompleteType(OpRange.getBegin(), DestPointee,
                               diag::err_bad_cast_incomplete,
                               DestRange)) {
    SrcExpr = ExprError();
    return;
  }
} else {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
    << DestPointee.getUnqualifiedType() << DestRange;
  SrcExpr = ExprError();
  return;
}

// C++0x 5.2.7p2: If T is a pointer type, v shall be an rvalue of a pointer to
//   complete class type, [...]. If T is an lvalue reference type, v shall be
//   an lvalue of a complete class type, [...]. If T is an rvalue reference
//   type, v shall be an expression having a complete class type, [...]
QualType SrcType = Self.Context.getCanonicalType(OrigSrcType);
QualType SrcPointee;
if (DestPointer) {
  if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
    SrcPointee = SrcPointer->getPointeeType();
  } else {
    Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ptr)
        << OrigSrcType << this->DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
} else if (DestReference->isLValueReferenceType()) {
  if (!SrcExpr.get()->isLValue()) {
    Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
      << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
  }
  SrcPointee = SrcType;
} else {
  // If we're dynamic_casting from a prvalue to an rvalue reference, we need
  // to materialize the prvalue before we bind the reference to it.
  if (SrcExpr.get()->isRValue())
    SrcExpr = Self.CreateMaterializeTemporaryExpr(
        SrcType, SrcExpr.get(), /*IsLValueReference*/ false);
  SrcPointee = SrcType;
}

const RecordType *SrcRecord = SrcPointee->getAs<RecordType>();
if (SrcRecord) {
  if (Self.RequireCompleteType(OpRange.getBegin(), SrcPointee,
                               diag::err_bad_cast_incomplete,
                               SrcExpr.get())) {
    SrcExpr = ExprError();
    return;
  }
} else {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
    << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

assert((DestPointer || DestReference) &&(((DestPointer || DestReference) && "Bad destination non-ptr/ref slipped through."
) ? static_cast<void> (0) : __assert_fail ("(DestPointer || DestReference) && \"Bad destination non-ptr/ref slipped through.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 839, __PRETTY_FUNCTION__))
  "Bad destination non-ptr/ref slipped through.")(((DestPointer || DestReference) && "Bad destination non-ptr/ref slipped through."
) ? static_cast<void> (0) : __assert_fail ("(DestPointer || DestReference) && \"Bad destination non-ptr/ref slipped through.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 839, __PRETTY_FUNCTION__));
assert((DestRecord || DestPointee->isVoidType()) &&(((DestRecord || DestPointee->isVoidType()) && "Bad destination pointee slipped through."
) ? static_cast<void> (0) : __assert_fail ("(DestRecord || DestPointee->isVoidType()) && \"Bad destination pointee slipped through.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 841, __PRETTY_FUNCTION__))
  "Bad destination pointee slipped through.")(((DestRecord || DestPointee->isVoidType()) && "Bad destination pointee slipped through."
) ? static_cast<void> (0) : __assert_fail ("(DestRecord || DestPointee->isVoidType()) && \"Bad destination pointee slipped through.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 841, __PRETTY_FUNCTION__));
assert(SrcRecord && "Bad source pointee slipped through.")((SrcRecord && "Bad source pointee slipped through.")
 ? static_cast<void> (0) : __assert_fail ("SrcRecord && \"Bad source pointee slipped through.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 842, __PRETTY_FUNCTION__));

// C++ 5.2.7p1: The dynamic_cast operator shall not cast away constness.
if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
  Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_qualifiers_away)
    << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
  SrcExpr = ExprError();
  return;
}

// C++ 5.2.7p3: If the type of v is the same as the required result type,
//   [except for cv].
if (DestRecord == SrcRecord) {
  Kind = CK_NoOp;
  return;
}

// C++ 5.2.7p5
// Upcasts are resolved statically.
if (DestRecord &&
    Self.IsDerivedFrom(OpRange.getBegin(), SrcPointee, DestPointee)) {
  if (Self.CheckDerivedToBaseConversion(SrcPointee, DestPointee,
                                         OpRange.getBegin(), OpRange,
                                         &BasePath)) {
    SrcExpr = ExprError();
    return;
  }

  Kind = CK_DerivedToBase;
  return;
}

// C++ 5.2.7p6: Otherwise, v shall be [polymorphic].
const RecordDecl *SrcDecl = SrcRecord->getDecl()->getDefinition();
assert(SrcDecl && "Definition missing")((SrcDecl && "Definition missing") ? static_cast<void
> (0) : __assert_fail ("SrcDecl && \"Definition missing\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 876, __PRETTY_FUNCTION__));
if (!cast<CXXRecordDecl>(SrcDecl)->isPolymorphic()) {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_polymorphic)
    << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
}

// dynamic_cast is not available with -fno-rtti.
// As an exception, dynamic_cast to void* is available because it doesn't
// use RTTI.
if (!Self.getLangOpts().RTTI && !DestPointee->isVoidType()) {
  Self.Diag(OpRange.getBegin(), diag::err_no_dynamic_cast_with_fno_rtti);
  SrcExpr = ExprError();
  return;
}

// Warns when dynamic_cast is used with RTTI data disabled.
if (!Self.getLangOpts().RTTIData) {
  bool MicrosoftABI =
      Self.getASTContext().getTargetInfo().getCXXABI().isMicrosoft();
  bool isClangCL = Self.getDiagnostics().getDiagnosticOptions().getFormat() ==
                   DiagnosticOptions::MSVC;
  if (MicrosoftABI || !DestPointee->isVoidType())
    Self.Diag(OpRange.getBegin(),
              diag::warn_no_dynamic_cast_with_rtti_disabled)
        << isClangCL;
}

// Done. Everything else is run-time checks.
Kind = CK_Dynamic;
906}

908/// CheckConstCast - Check that a const_cast\<DestType\>(SrcExpr) is valid.
909/// Refer to C++ 5.2.11 for details. const_cast is typically used in code
910/// like this:
911/// const char *str = "literal";
912/// legacy_function(const_cast\<char*\>(str));
913void CastOperation::CheckConstCast() {
CheckNoDerefRAII NoderefCheck(*this);

if (ValueKind == VK_RValue)
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
else if (isPlaceholder())
  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
  return;

unsigned msg = diag::err_bad_cxx_cast_generic;
auto TCR = TryConstCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg);
if (TCR != TC_Success && msg != 0) {
  Self.Diag(OpRange.getBegin(), msg) << CT_Const
    << SrcExpr.get()->getType() << DestType << OpRange;
}
if (!isValidCast(TCR))
  SrcExpr = ExprError();
931}

933void CastOperation::CheckAddrspaceCast() {
unsigned msg = diag::err_bad_cxx_cast_generic;
auto TCR =
    TryAddressSpaceCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg, Kind);
if (TCR != TC_Success && msg != 0) {
  Self.Diag(OpRange.getBegin(), msg)
      << CT_Addrspace << SrcExpr.get()->getType() << DestType << OpRange;
}
if (!isValidCast(TCR))
  SrcExpr = ExprError();
943}

945/// Check that a reinterpret_cast\<DestType\>(SrcExpr) is not used as upcast
946/// or downcast between respective pointers or references.
947static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
                                        QualType DestType,
                                        SourceRange OpRange) {
QualType SrcType = SrcExpr->getType();
// When casting from pointer or reference, get pointee type; use original
// type otherwise.
const CXXRecordDecl *SrcPointeeRD = SrcType->getPointeeCXXRecordDecl();
const CXXRecordDecl *SrcRD =
  SrcPointeeRD ? SrcPointeeRD : SrcType->getAsCXXRecordDecl();

// Examining subobjects for records is only possible if the complete and
// valid definition is available.  Also, template instantiation is not
// allowed here.
if (!SrcRD || !SrcRD->isCompleteDefinition() || SrcRD->isInvalidDecl())
  return;

const CXXRecordDecl *DestRD = DestType->getPointeeCXXRecordDecl();

if (!DestRD || !DestRD->isCompleteDefinition() || DestRD->isInvalidDecl())
  return;

enum {
  ReinterpretUpcast,
  ReinterpretDowncast
} ReinterpretKind;

CXXBasePaths BasePaths;

if (SrcRD->isDerivedFrom(DestRD, BasePaths))
  ReinterpretKind = ReinterpretUpcast;
else if (DestRD->isDerivedFrom(SrcRD, BasePaths))
  ReinterpretKind = ReinterpretDowncast;
else
  return;

bool VirtualBase = true;
bool NonZeroOffset = false;
for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(),
                                        E = BasePaths.end();
     I != E; ++I) {
  const CXXBasePath &Path = *I;
  CharUnits Offset = CharUnits::Zero();
  bool IsVirtual = false;
  for (CXXBasePath::const_iterator IElem = Path.begin(), EElem = Path.end();
       IElem != EElem; ++IElem) {
    IsVirtual = IElem->Base->isVirtual();
    if (IsVirtual)
      break;
    const CXXRecordDecl *BaseRD = IElem->Base->getType()->getAsCXXRecordDecl();
    assert(BaseRD && "Base type should be a valid unqualified class type")((BaseRD && "Base type should be a valid unqualified class type"
) ? static_cast<void> (0) : __assert_fail ("BaseRD && \"Base type should be a valid unqualified class type\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 996, __PRETTY_FUNCTION__));
    // Don't check if any base has invalid declaration or has no definition
    // since it has no layout info.
    const CXXRecordDecl *Class = IElem->Class,
                        *ClassDefinition = Class->getDefinition();
    if (Class->isInvalidDecl() || !ClassDefinition ||
        !ClassDefinition->isCompleteDefinition())
      return;

    const ASTRecordLayout &DerivedLayout =
        Self.Context.getASTRecordLayout(Class);
    Offset += DerivedLayout.getBaseClassOffset(BaseRD);
  }
  if (!IsVirtual) {
    // Don't warn if any path is a non-virtually derived base at offset zero.
    if (Offset.isZero())
      return;
    // Offset makes sense only for non-virtual bases.
    else
      NonZeroOffset = true;
  }
  VirtualBase = VirtualBase && IsVirtual;
}

(void) NonZeroOffset; // Silence set but not used warning.
assert((VirtualBase || NonZeroOffset) &&(((VirtualBase || NonZeroOffset) && "Should have returned if has non-virtual base with zero offset"
) ? static_cast<void> (0) : __assert_fail ("(VirtualBase || NonZeroOffset) && \"Should have returned if has non-virtual base with zero offset\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 1022, __PRETTY_FUNCTION__))
       "Should have returned if has non-virtual base with zero offset")(((VirtualBase || NonZeroOffset) && "Should have returned if has non-virtual base with zero offset"
) ? static_cast<void> (0) : __assert_fail ("(VirtualBase || NonZeroOffset) && \"Should have returned if has non-virtual base with zero offset\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 1022, __PRETTY_FUNCTION__));

QualType BaseType =
    ReinterpretKind == ReinterpretUpcast? DestType : SrcType;
QualType DerivedType =
    ReinterpretKind == ReinterpretUpcast? SrcType : DestType;

SourceLocation BeginLoc = OpRange.getBegin();
Self.Diag(BeginLoc, diag::warn_reinterpret_different_from_static)
  << DerivedType << BaseType << !VirtualBase << int(ReinterpretKind)
  << OpRange;
Self.Diag(BeginLoc, diag::note_reinterpret_updowncast_use_static)
  << int(ReinterpretKind)
  << FixItHint::CreateReplacement(BeginLoc, "static_cast");
1036}

1038/// CheckReinterpretCast - Check that a reinterpret_cast\<DestType\>(SrcExpr) is
1039/// valid.
1040/// Refer to C++ 5.2.10 for details. reinterpret_cast is typically used in code
1041/// like this:
1042/// char *bytes = reinterpret_cast\<char*\>(int_ptr);
1043void CastOperation::CheckReinterpretCast() {
if (ValueKind == VK_RValue && !isPlaceholder(BuiltinType::Overload))
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
else
  checkNonOverloadPlaceholders();
if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
  return;

unsigned msg = diag::err_bad_cxx_cast_generic;
TryCastResult tcr =
  TryReinterpretCast(Self, SrcExpr, DestType,
                     /*CStyle*/false, OpRange, msg, Kind);
if (tcr != TC_Success && msg != 0) {
  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
    return;
  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
    //FIXME: &f<int>; is overloaded and resolvable
    Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_overload)
      << OverloadExpr::find(SrcExpr.get()).Expression->getName()
      << DestType << OpRange;
    Self.NoteAllOverloadCandidates(SrcExpr.get());

  } else {
    diagnoseBadCast(Self, msg, CT_Reinterpret, OpRange, SrcExpr.get(),
                    DestType, /*listInitialization=*/false);
  }
}

if (isValidCast(tcr)) {
  if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
    checkObjCConversion(Sema::CCK_OtherCast);
  DiagnoseReinterpretUpDownCast(Self, SrcExpr.get(), DestType, OpRange);
} else {
  SrcExpr = ExprError();
}
1078}


1081/// CheckStaticCast - Check that a static_cast\<DestType\>(SrcExpr) is valid.
1082/// Refer to C++ 5.2.9 for details. Static casts are mostly used for making
1083/// implicit conversions explicit and getting rid of data loss warnings.
1084void CastOperation::CheckStaticCast() {
CheckNoDerefRAII NoderefCheck(*this);

if (isPlaceholder()) {
11
←
Taking false branch→
  checkNonOverloadPlaceholders();
  if (SrcExpr.isInvalid())
    return;
}

// This test is outside everything else because it's the only case where
// a non-lvalue-reference target type does not lead to decay.
// C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
if (DestType->isVoidType()) {
12
←
Taking false branch→
  Kind = CK_ToVoid;

  if (claimPlaceholder(BuiltinType::Overload)) {
    Self.ResolveAndFixSingleFunctionTemplateSpecialization(SrcExpr,
              false, // Decay Function to ptr
              true, // Complain
              OpRange, DestType, diag::err_bad_static_cast_overload);
    if (SrcExpr.isInvalid())
      return;
  }

  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
  return;
}

if (ValueKind == VK_RValue && !DestType->isRecordType() &&
13
←
Assuming field 'ValueKind' is not equal to VK_RValue→
    !isPlaceholder(BuiltinType::Overload)) {
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
    return;
}

unsigned msg = diag::err_bad_cxx_cast_generic;
TryCastResult tcr
  = TryStaticCast(Self, SrcExpr, DestType, Sema::CCK_OtherCast, OpRange, msg,
14
←
Calling 'TryStaticCast'→
                  Kind, BasePath, /*ListInitialization=*/false);
if (tcr != TC_Success && msg != 0) {
  if (SrcExpr.isInvalid())
    return;
  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
    OverloadExpr* oe = OverloadExpr::find(SrcExpr.get()).Expression;
    Self.Diag(OpRange.getBegin(), diag::err_bad_static_cast_overload)
      << oe->getName() << DestType << OpRange
      << oe->getQualifierLoc().getSourceRange();
    Self.NoteAllOverloadCandidates(SrcExpr.get());
  } else {
    diagnoseBadCast(Self, msg, CT_Static, OpRange, SrcExpr.get(), DestType,
                    /*listInitialization=*/false);
  }
}

if (isValidCast(tcr)) {
  if (Kind == CK_BitCast)
    checkCastAlign();
  if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
    checkObjCConversion(Sema::CCK_OtherCast);
} else {
  SrcExpr = ExprError();
}
1146}

1148static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType) {
auto *SrcPtrType = SrcType->getAs<PointerType>();
if (!SrcPtrType)
  return false;
auto *DestPtrType = DestType->getAs<PointerType>();
if (!DestPtrType)
  return false;
return SrcPtrType->getPointeeType().getAddressSpace() !=
       DestPtrType->getPointeeType().getAddressSpace();
1157}

1159/// TryStaticCast - Check if a static cast can be performed, and do so if
1160/// possible. If @p CStyle, ignore access restrictions on hierarchy casting
1161/// and casting away constness.
1162static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
                                 QualType DestType,
                                 Sema::CheckedConversionKind CCK,
                                 SourceRange OpRange, unsigned &msg,
                                 CastKind &Kind, CXXCastPath &BasePath,
                                 bool ListInitialization) {
// Determine whether we have the semantics of a C-style cast.
bool CStyle
  = (CCK14.1
'CCK' is not equal to CCK_CStyleCast
1
'CCK' is not equal to CCK_CStyleCast
 == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);

// The order the tests is not entirely arbitrary. There is one conversion
// that can be handled in two different ways. Given:
// struct A {};
// struct B : public A {
//   B(); B(const A&);
// };
// const A &a = B();
// the cast static_cast<const B&>(a) could be seen as either a static
// reference downcast, or an explicit invocation of the user-defined
// conversion using B's conversion constructor.
// DR 427 specifies that the downcast is to be applied here.

// C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
// Done outside this function.

TryCastResult tcr;

// C++ 5.2.9p5, reference downcast.
// See the function for details.
// DR 427 specifies that this is to be applied before paragraph 2.
tcr = TryStaticReferenceDowncast(Self, SrcExpr.get(), DestType, CStyle,
                                 OpRange, msg, Kind, BasePath);
if (tcr14.2
'tcr' is equal to TC_NotApplicable
2
'tcr' is equal to TC_NotApplicable
 != TC_NotApplicable)
15
←
Taking false branch→
  return tcr;

// C++11 [expr.static.cast]p3:
//   A glvalue of type "cv1 T1" can be cast to type "rvalue reference to cv2
//   T2" if "cv2 T2" is reference-compatible with "cv1 T1".
tcr = TryLValueToRValueCast(Self, SrcExpr.get(), DestType, CStyle, Kind,
                            BasePath, msg);
if (tcr15.1
'tcr' is equal to TC_NotApplicable
1
'tcr' is equal to TC_NotApplicable
 != TC_NotApplicable)
16
←
Taking false branch→
  return tcr;

// C++ 5.2.9p2: An expression e can be explicitly converted to a type T
//   [...] if the declaration "T t(e);" is well-formed, [...].
tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg,
                            Kind, ListInitialization);
if (SrcExpr.isInvalid())
17
←
Assuming the condition is false→
18
←
Taking false branch→
  return TC_Failed;
if (tcr18.1
'tcr' is equal to TC_NotApplicable
1
'tcr' is equal to TC_NotApplicable
 != TC_NotApplicable)
19
←
Taking false branch→
  return tcr;

// C++ 5.2.9p6: May apply the reverse of any standard conversion, except
// lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
// conversions, subject to further restrictions.
// Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
// of qualification conversions impossible.
// In the CStyle case, the earlier attempt to const_cast should have taken
// care of reverse qualification conversions.

QualType SrcType = Self.Context.getCanonicalType(SrcExpr.get()->getType());

// C++0x 5.2.9p9: A value of a scoped enumeration type can be explicitly
// converted to an integral type. [...] A value of a scoped enumeration type
// can also be explicitly converted to a floating-point type [...].
if (const EnumType *Enum20.1
'Enum' is null
1
'Enum' is null
 = SrcType->getAs<EnumType>()) {
20
←
Assuming the object is not a 'EnumType'→
21
←
Taking false branch→
  if (Enum->getDecl()->isScoped()) {
    if (DestType->isBooleanType()) {
      Kind = CK_IntegralToBoolean;
      return TC_Success;
    } else if (DestType->isIntegralType(Self.Context)) {
      Kind = CK_IntegralCast;
      return TC_Success;
    } else if (DestType->isRealFloatingType()) {
      Kind = CK_IntegralToFloating;
      return TC_Success;
    }
  }
}

// Reverse integral promotion/conversion. All such conversions are themselves
// again integral promotions or conversions and are thus already handled by
// p2 (TryDirectInitialization above).
// (Note: any data loss warnings should be suppressed.)
// The exception is the reverse of enum->integer, i.e. integer->enum (and
// enum->enum). See also C++ 5.2.9p7.
// The same goes for reverse floating point promotion/conversion and
// floating-integral conversions. Again, only floating->enum is relevant.
if (DestType->isEnumeralType()) {
22
←
Calling 'Type::isEnumeralType'→
25
←
Returning from 'Type::isEnumeralType'→
26
←
Taking true branch→
  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
27
←
Assuming the condition is false→
28
←
Taking false branch→
                               diag::err_bad_cast_incomplete)) {
    SrcExpr = ExprError();
    return TC_Failed;
  }
  if (SrcType->isIntegralOrEnumerationType()) {
29
←
Calling 'Type::isIntegralOrEnumerationType'→
39
←
Returning from 'Type::isIntegralOrEnumerationType'→
40
←
Taking true branch→
    // [expr.static.cast]p10 If the enumeration type has a fixed underlying
    // type, the value is first converted to that type by integral conversion
    const EnumType *Enum = DestType->getAs<EnumType>();
41
←
Assuming the object is not a 'EnumType'→
42
←
'Enum' initialized to a null pointer value→
    Kind = Enum->getDecl()->isFixed() &&
43
←
Called C++ object pointer is null
                   Enum->getDecl()->getIntegerType()->isBooleanType()
               ? CK_IntegralToBoolean
               : CK_IntegralCast;
    return TC_Success;
  } else if (SrcType->isRealFloatingType())   {
    Kind = CK_FloatingToIntegral;
    return TC_Success;
  }
}

// Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
// C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
tcr = TryStaticPointerDowncast(Self, SrcType, DestType, CStyle, OpRange, msg,
                               Kind, BasePath);
if (tcr != TC_NotApplicable)
  return tcr;

// Reverse member pointer conversion. C++ 4.11 specifies member pointer
// conversion. C++ 5.2.9p9 has additional information.
// DR54's access restrictions apply here also.
tcr = TryStaticMemberPointerUpcast(Self, SrcExpr, SrcType, DestType, CStyle,
                                   OpRange, msg, Kind, BasePath);
if (tcr != TC_NotApplicable)
  return tcr;

// Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
// void*. C++ 5.2.9p10 specifies additional restrictions, which really is
// just the usual constness stuff.
if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
  QualType SrcPointee = SrcPointer->getPointeeType();
  if (SrcPointee->isVoidType()) {
    if (const PointerType *DestPointer = DestType->getAs<PointerType>()) {
      QualType DestPointee = DestPointer->getPointeeType();
      if (DestPointee->isIncompleteOrObjectType()) {
        // This is definitely the intended conversion, but it might fail due
        // to a qualifier violation. Note that we permit Objective-C lifetime
        // and GC qualifier mismatches here.
        if (!CStyle) {
          Qualifiers DestPointeeQuals = DestPointee.getQualifiers();
          Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers();
          DestPointeeQuals.removeObjCGCAttr();
          DestPointeeQuals.removeObjCLifetime();
          SrcPointeeQuals.removeObjCGCAttr();
          SrcPointeeQuals.removeObjCLifetime();
          if (DestPointeeQuals != SrcPointeeQuals &&
              !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) {
            msg = diag::err_bad_cxx_cast_qualifiers_away;
            return TC_Failed;
          }
        }
        Kind = IsAddressSpaceConversion(SrcType, DestType)
                   ? CK_AddressSpaceConversion
                   : CK_BitCast;
        return TC_Success;
      }

      // Microsoft permits static_cast from 'pointer-to-void' to
      // 'pointer-to-function'.
      if (!CStyle && Self.getLangOpts().MSVCCompat &&
          DestPointee->isFunctionType()) {
        Self.Diag(OpRange.getBegin(), diag::ext_ms_cast_fn_obj) << OpRange;
        Kind = CK_BitCast;
        return TC_Success;
      }
    }
    else if (DestType->isObjCObjectPointerType()) {
      // allow both c-style cast and static_cast of objective-c pointers as
      // they are pervasive.
      Kind = CK_CPointerToObjCPointerCast;
      return TC_Success;
    }
    else if (CStyle && DestType->isBlockPointerType()) {
      // allow c-style cast of void * to block pointers.
      Kind = CK_AnyPointerToBlockPointerCast;
      return TC_Success;
    }
  }
}
// Allow arbitrary objective-c pointer conversion with static casts.
if (SrcType->isObjCObjectPointerType() &&
    DestType->isObjCObjectPointerType()) {
  Kind = CK_BitCast;
  return TC_Success;
}
// Allow ns-pointer to cf-pointer conversion in either direction
// with static casts.
if (!CStyle &&
    Self.CheckTollFreeBridgeStaticCast(DestType, SrcExpr.get(), Kind))
  return TC_Success;

// See if it looks like the user is trying to convert between
// related record types, and select a better diagnostic if so.
if (auto SrcPointer = SrcType->getAs<PointerType>())
  if (auto DestPointer = DestType->getAs<PointerType>())
    if (SrcPointer->getPointeeType()->getAs<RecordType>() &&
        DestPointer->getPointeeType()->getAs<RecordType>())
     msg = diag::err_bad_cxx_cast_unrelated_class;

// We tried everything. Everything! Nothing works! :-(
return TC_NotApplicable;
1361}

1363/// Tests whether a conversion according to N2844 is valid.
1364TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
                                  QualType DestType, bool CStyle,
                                  CastKind &Kind, CXXCastPath &BasePath,
                                  unsigned &msg) {
// C++11 [expr.static.cast]p3:
//   A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
//   cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
const RValueReferenceType *R = DestType->getAs<RValueReferenceType>();
if (!R)
  return TC_NotApplicable;

if (!SrcExpr->isGLValue())
  return TC_NotApplicable;

// Because we try the reference downcast before this function, from now on
// this is the only cast possibility, so we issue an error if we fail now.
// FIXME: Should allow casting away constness if CStyle.
QualType FromType = SrcExpr->getType();
QualType ToType = R->getPointeeType();
if (CStyle) {
  FromType = FromType.getUnqualifiedType();
  ToType = ToType.getUnqualifiedType();
}

Sema::ReferenceConversions RefConv;
Sema::ReferenceCompareResult RefResult = Self.CompareReferenceRelationship(
    SrcExpr->getBeginLoc(), ToType, FromType, &RefConv);
if (RefResult != Sema::Ref_Compatible) {
  if (CStyle || RefResult == Sema::Ref_Incompatible)
    return TC_NotApplicable;
  // Diagnose types which are reference-related but not compatible here since
  // we can provide better diagnostics. In these cases forwarding to
  // [expr.static.cast]p4 should never result in a well-formed cast.
  msg = SrcExpr->isLValue() ? diag::err_bad_lvalue_to_rvalue_cast
                            : diag::err_bad_rvalue_to_rvalue_cast;
  return TC_Failed;
}

if (RefConv & Sema::ReferenceConversions::DerivedToBase) {
  Kind = CK_DerivedToBase;
  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
                     /*DetectVirtual=*/true);
  if (!Self.IsDerivedFrom(SrcExpr->getBeginLoc(), SrcExpr->getType(),
                          R->getPointeeType(), Paths))
    return TC_NotApplicable;

  Self.BuildBasePathArray(Paths, BasePath);
} else
  Kind = CK_NoOp;

return TC_Success;
1415}

1417/// Tests whether a conversion according to C++ 5.2.9p5 is valid.
1418TryCastResult
1419TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType,
                         bool CStyle, SourceRange OpRange,
                         unsigned &msg, CastKind &Kind,
                         CXXCastPath &BasePath) {
// C++ 5.2.9p5: An lvalue of type "cv1 B", where B is a class type, can be
//   cast to type "reference to cv2 D", where D is a class derived from B,
//   if a valid standard conversion from "pointer to D" to "pointer to B"
//   exists, cv2 >= cv1, and B is not a virtual base class of D.
// In addition, DR54 clarifies that the base must be accessible in the
// current context. Although the wording of DR54 only applies to the pointer
// variant of this rule, the intent is clearly for it to apply to the this
// conversion as well.

const ReferenceType *DestReference = DestType->getAs<ReferenceType>();
if (!DestReference) {
  return TC_NotApplicable;
}
bool RValueRef = DestReference->isRValueReferenceType();
if (!RValueRef && !SrcExpr->isLValue()) {
  // We know the left side is an lvalue reference, so we can suggest a reason.
  msg = diag::err_bad_cxx_cast_rvalue;
  return TC_NotApplicable;
}

QualType DestPointee = DestReference->getPointeeType();

// FIXME: If the source is a prvalue, we should issue a warning (because the
// cast always has undefined behavior), and for AST consistency, we should
// materialize a temporary.
return TryStaticDowncast(Self,
                         Self.Context.getCanonicalType(SrcExpr->getType()),
                         Self.Context.getCanonicalType(DestPointee), CStyle,
                         OpRange, SrcExpr->getType(), DestType, msg, Kind,
                         BasePath);
1453}

1455/// Tests whether a conversion according to C++ 5.2.9p8 is valid.
1456TryCastResult
1457TryStaticPointerDowncast(Sema &Self, QualType SrcType, QualType DestType,
                       bool CStyle, SourceRange OpRange,
                       unsigned &msg, CastKind &Kind,
                       CXXCastPath &BasePath) {
// C++ 5.2.9p8: An rvalue of type "pointer to cv1 B", where B is a class
//   type, can be converted to an rvalue of type "pointer to cv2 D", where D
//   is a class derived from B, if a valid standard conversion from "pointer
//   to D" to "pointer to B" exists, cv2 >= cv1, and B is not a virtual base
//   class of D.
// In addition, DR54 clarifies that the base must be accessible in the
// current context.

const PointerType *DestPointer = DestType->getAs<PointerType>();
if (!DestPointer) {
  return TC_NotApplicable;
}

const PointerType *SrcPointer = SrcType->getAs<PointerType>();
if (!SrcPointer) {
  msg = diag::err_bad_static_cast_pointer_nonpointer;
  return TC_NotApplicable;
}

return TryStaticDowncast(Self,
                 Self.Context.getCanonicalType(SrcPointer->getPointeeType()),
                Self.Context.getCanonicalType(DestPointer->getPointeeType()),
                         CStyle, OpRange, SrcType, DestType, msg, Kind,
                         BasePath);
1485}

1487/// TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and
1488/// TryStaticPointerDowncast. Tests whether a static downcast from SrcType to
1489/// DestType is possible and allowed.
1490TryCastResult
1491TryStaticDowncast(Sema &Self, CanQualType SrcType, CanQualType DestType,
                bool CStyle, SourceRange OpRange, QualType OrigSrcType,
                QualType OrigDestType, unsigned &msg,
                CastKind &Kind, CXXCastPath &BasePath) {
// We can only work with complete types. But don't complain if it doesn't work
if (!Self.isCompleteType(OpRange.getBegin(), SrcType) ||
    !Self.isCompleteType(OpRange.getBegin(), DestType))
  return TC_NotApplicable;

// Downcast can only happen in class hierarchies, so we need classes.
if (!DestType->getAs<RecordType>() || !SrcType->getAs<RecordType>()) {
  return TC_NotApplicable;
}

CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
                   /*DetectVirtual=*/true);
if (!Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths)) {
  return TC_NotApplicable;
}

// Target type does derive from source type. Now we're serious. If an error
// appears now, it's not ignored.
// This may not be entirely in line with the standard. Take for example:
// struct A {};
// struct B : virtual A {
//   B(A&);
// };
//
// void f()
// {
//   (void)static_cast<const B&>(*((A*)0));
// }
// As far as the standard is concerned, p5 does not apply (A is virtual), so
// p2 should be used instead - "const B& t(*((A*)0));" is perfectly valid.
// However, both GCC and Comeau reject this example, and accepting it would
// mean more complex code if we're to preserve the nice error message.
// FIXME: Being 100% compliant here would be nice to have.

// Must preserve cv, as always, unless we're in C-style mode.
if (!CStyle && !DestType.isAtLeastAsQualifiedAs(SrcType)) {
  msg = diag::err_bad_cxx_cast_qualifiers_away;
  return TC_Failed;
}

if (Paths.isAmbiguous(SrcType.getUnqualifiedType())) {
  // This code is analoguous to that in CheckDerivedToBaseConversion, except
  // that it builds the paths in reverse order.
  // To sum up: record all paths to the base and build a nice string from
  // them. Use it to spice up the error message.
  if (!Paths.isRecordingPaths()) {
    Paths.clear();
    Paths.setRecordingPaths(true);
    Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths);
  }
  std::string PathDisplayStr;
  std::set<unsigned> DisplayedPaths;
  for (clang::CXXBasePath &Path : Paths) {
    if (DisplayedPaths.insert(Path.back().SubobjectNumber).second) {
      // We haven't displayed a path to this particular base
      // class subobject yet.
      PathDisplayStr += "\n    ";
      for (CXXBasePathElement &PE : llvm::reverse(Path))
        PathDisplayStr += PE.Base->getType().getAsString() + " -> ";
      PathDisplayStr += QualType(DestType).getAsString();
    }
  }

  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_base_to_derived_cast)
    << QualType(SrcType).getUnqualifiedType()
    << QualType(DestType).getUnqualifiedType()
    << PathDisplayStr << OpRange;
  msg = 0;
  return TC_Failed;
}

if (Paths.getDetectedVirtual() != nullptr) {
  QualType VirtualBase(Paths.getDetectedVirtual(), 0);
  Self.Diag(OpRange.getBegin(), diag::err_static_downcast_via_virtual)
    << OrigSrcType << OrigDestType << VirtualBase << OpRange;
  msg = 0;
  return TC_Failed;
}

if (!CStyle) {
  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
                                    SrcType, DestType,
                                    Paths.front(),
                              diag::err_downcast_from_inaccessible_base)) {
  case Sema::AR_accessible:
  case Sema::AR_delayed:     // be optimistic
  case Sema::AR_dependent:   // be optimistic
    break;

  case Sema::AR_inaccessible:
    msg = 0;
    return TC_Failed;
  }
}

Self.BuildBasePathArray(Paths, BasePath);
Kind = CK_BaseToDerived;
return TC_Success;
1593}

1595/// TryStaticMemberPointerUpcast - Tests whether a conversion according to
1596/// C++ 5.2.9p9 is valid:
1597///
1598///   An rvalue of type "pointer to member of D of type cv1 T" can be
1599///   converted to an rvalue of type "pointer to member of B of type cv2 T",
1600///   where B is a base class of D [...].
1601///
1602TryCastResult
1603TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr, QualType SrcType,
                           QualType DestType, bool CStyle,
                           SourceRange OpRange,
                           unsigned &msg, CastKind &Kind,
                           CXXCastPath &BasePath) {
const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>();
if (!DestMemPtr)
  return TC_NotApplicable;

bool WasOverloadedFunction = false;
DeclAccessPair FoundOverload;
if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
  if (FunctionDecl *Fn
        = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(), DestType, false,
                                                  FoundOverload)) {
    CXXMethodDecl *M = cast<CXXMethodDecl>(Fn);
    SrcType = Self.Context.getMemberPointerType(Fn->getType(),
                    Self.Context.getTypeDeclType(M->getParent()).getTypePtr());
    WasOverloadedFunction = true;
  }
}

const MemberPointerType *SrcMemPtr = SrcType->getAs<MemberPointerType>();
if (!SrcMemPtr) {
  msg = diag::err_bad_static_cast_member_pointer_nonmp;
  return TC_NotApplicable;
}

// Lock down the inheritance model right now in MS ABI, whether or not the
// pointee types are the same.
if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
}

// T == T, modulo cv
if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
                                         DestMemPtr->getPointeeType()))
  return TC_NotApplicable;

// B base of D
QualType SrcClass(SrcMemPtr->getClass(), 0);
QualType DestClass(DestMemPtr->getClass(), 0);
CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
                /*DetectVirtual=*/true);
if (!Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths))
  return TC_NotApplicable;

// B is a base of D. But is it an allowed base? If not, it's a hard error.
if (Paths.isAmbiguous(Self.Context.getCanonicalType(DestClass))) {
  Paths.clear();
  Paths.setRecordingPaths(true);
  bool StillOkay =
      Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths);
  assert(StillOkay)((StillOkay) ? static_cast<void> (0) : __assert_fail ("StillOkay"
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 1657, __PRETTY_FUNCTION__));
  (void)StillOkay;
  std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
    << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
  msg = 0;
  return TC_Failed;
}

if (const RecordType *VBase = Paths.getDetectedVirtual()) {
  Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
    << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
  msg = 0;
  return TC_Failed;
}

if (!CStyle) {
  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
                                    DestClass, SrcClass,
                                    Paths.front(),
                                    diag::err_upcast_to_inaccessible_base)) {
  case Sema::AR_accessible:
  case Sema::AR_delayed:
  case Sema::AR_dependent:
    // Optimistically assume that the delayed and dependent cases
    // will work out.
    break;

  case Sema::AR_inaccessible:
    msg = 0;
    return TC_Failed;
  }
}

if (WasOverloadedFunction) {
  // Resolve the address of the overloaded function again, this time
  // allowing complaints if something goes wrong.
  FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
                                                             DestType,
                                                             true,
                                                             FoundOverload);
  if (!Fn) {
    msg = 0;
    return TC_Failed;
  }

  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr, FoundOverload, Fn);
  if (!SrcExpr.isUsable()) {
    msg = 0;
    return TC_Failed;
  }
}

Self.BuildBasePathArray(Paths, BasePath);
Kind = CK_DerivedToBaseMemberPointer;
return TC_Success;
1713}

1715/// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
1716/// is valid:
1717///
1718///   An expression e can be explicitly converted to a type T using a
1719///   @c static_cast if the declaration "T t(e);" is well-formed [...].
1720TryCastResult
1721TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType,
                    Sema::CheckedConversionKind CCK,
                    SourceRange OpRange, unsigned &msg,
                    CastKind &Kind, bool ListInitialization) {
if (DestType->isRecordType()) {
  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
                               diag::err_bad_cast_incomplete) ||
      Self.RequireNonAbstractType(OpRange.getBegin(), DestType,
                                  diag::err_allocation_of_abstract_type)) {
    msg = 0;
    return TC_Failed;
  }
}

InitializedEntity Entity = InitializedEntity::InitializeTemporary(DestType);
InitializationKind InitKind
  = (CCK == Sema::CCK_CStyleCast)
      ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange,
                                             ListInitialization)
  : (CCK == Sema::CCK_FunctionalCast)
      ? InitializationKind::CreateFunctionalCast(OpRange, ListInitialization)
  : InitializationKind::CreateCast(OpRange);
Expr *SrcExprRaw = SrcExpr.get();
// FIXME: Per DR242, we should check for an implicit conversion sequence
// or for a constructor that could be invoked by direct-initialization
// here, not for an initialization sequence.
InitializationSequence InitSeq(Self, Entity, InitKind, SrcExprRaw);

// At this point of CheckStaticCast, if the destination is a reference,
// or the expression is an overload expression this has to work.
// There is no other way that works.
// On the other hand, if we're checking a C-style cast, we've still got
// the reinterpret_cast way.
bool CStyle
  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType()))
  return TC_NotApplicable;

ExprResult Result = InitSeq.Perform(Self, Entity, InitKind, SrcExprRaw);
if (Result.isInvalid()) {
  msg = 0;
  return TC_Failed;
}

if (InitSeq.isConstructorInitialization())
  Kind = CK_ConstructorConversion;
else
  Kind = CK_NoOp;

SrcExpr = Result;
return TC_Success;
1772}

1774/// TryConstCast - See if a const_cast from source to destination is allowed,
1775/// and perform it if it is.
1776static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
                                QualType DestType, bool CStyle,
                                unsigned &msg) {
DestType = Self.Context.getCanonicalType(DestType);
QualType SrcType = SrcExpr.get()->getType();
bool NeedToMaterializeTemporary = false;

if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
  // C++11 5.2.11p4:
  //   if a pointer to T1 can be explicitly converted to the type "pointer to
  //   T2" using a const_cast, then the following conversions can also be
  //   made:
  //    -- an lvalue of type T1 can be explicitly converted to an lvalue of
  //       type T2 using the cast const_cast<T2&>;
  //    -- a glvalue of type T1 can be explicitly converted to an xvalue of
  //       type T2 using the cast const_cast<T2&&>; and
  //    -- if T1 is a class type, a prvalue of type T1 can be explicitly
  //       converted to an xvalue of type T2 using the cast const_cast<T2&&>.

  if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr.get()->isLValue()) {
    // Cannot const_cast non-lvalue to lvalue reference type. But if this
    // is C-style, static_cast might find a way, so we simply suggest a
    // message and tell the parent to keep searching.
    msg = diag::err_bad_cxx_cast_rvalue;
    return TC_NotApplicable;
  }

  if (isa<RValueReferenceType>(DestTypeTmp) && SrcExpr.get()->isRValue()) {
    if (!SrcType->isRecordType()) {
      // Cannot const_cast non-class prvalue to rvalue reference type. But if
      // this is C-style, static_cast can do this.
      msg = diag::err_bad_cxx_cast_rvalue;
      return TC_NotApplicable;
    }

    // Materialize the class prvalue so that the const_cast can bind a
    // reference to it.
    NeedToMaterializeTemporary = true;
  }

  // It's not completely clear under the standard whether we can
  // const_cast bit-field gl-values.  Doing so would not be
  // intrinsically complicated, but for now, we say no for
  // consistency with other compilers and await the word of the
  // committee.
  if (SrcExpr.get()->refersToBitField()) {
    msg = diag::err_bad_cxx_cast_bitfield;
    return TC_NotApplicable;
  }

  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
  SrcType = Self.Context.getPointerType(SrcType);
}

// C++ 5.2.11p5: For a const_cast involving pointers to data members [...]
//   the rules for const_cast are the same as those used for pointers.

if (!DestType->isPointerType() &&
    !DestType->isMemberPointerType() &&
    !DestType->isObjCObjectPointerType()) {
  // Cannot cast to non-pointer, non-reference type. Note that, if DestType
  // was a reference type, we converted it to a pointer above.
  // The status of rvalue references isn't entirely clear, but it looks like
  // conversion to them is simply invalid.
  // C++ 5.2.11p3: For two pointer types [...]
  if (!CStyle)
    msg = diag::err_bad_const_cast_dest;
  return TC_NotApplicable;
}
if (DestType->isFunctionPointerType() ||
    DestType->isMemberFunctionPointerType()) {
  // Cannot cast direct function pointers.
  // C++ 5.2.11p2: [...] where T is any object type or the void type [...]
  // T is the ultimate pointee of source and target type.
  if (!CStyle)
    msg = diag::err_bad_const_cast_dest;
  return TC_NotApplicable;
}

// C++ [expr.const.cast]p3:
//   "For two similar types T1 and T2, [...]"
//
// We only allow a const_cast to change cvr-qualifiers, not other kinds of
// type qualifiers. (Likewise, we ignore other changes when determining
// whether a cast casts away constness.)
if (!Self.Context.hasCvrSimilarType(SrcType, DestType))
  return TC_NotApplicable;

if (NeedToMaterializeTemporary)
  // This is a const_cast from a class prvalue to an rvalue reference type.
  // Materialize a temporary to store the result of the conversion.
  SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcExpr.get()->getType(),
                                                SrcExpr.get(),
                                                /*IsLValueReference*/ false);

return TC_Success;
1872}

1874// Checks for undefined behavior in reinterpret_cast.
1875// The cases that is checked for is:
1876// *reinterpret_cast<T*>(&a)
1877// reinterpret_cast<T&>(a)
1878// where accessing 'a' as type 'T' will result in undefined behavior.
1879void Sema::CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType,
                                        bool IsDereference,
                                        SourceRange Range) {
unsigned DiagID = IsDereference ?
                      diag::warn_pointer_indirection_from_incompatible_type :
                      diag::warn_undefined_reinterpret_cast;

if (Diags.isIgnored(DiagID, Range.getBegin()))
  return;

QualType SrcTy, DestTy;
if (IsDereference) {
  if (!SrcType->getAs<PointerType>() || !DestType->getAs<PointerType>()) {
    return;
  }
  SrcTy = SrcType->getPointeeType();
  DestTy = DestType->getPointeeType();
} else {
  if (!DestType->getAs<ReferenceType>()) {
    return;
  }
  SrcTy = SrcType;
  DestTy = DestType->getPointeeType();
}

// Cast is compatible if the types are the same.
if (Context.hasSameUnqualifiedType(DestTy, SrcTy)) {
  return;
}
// or one of the types is a char or void type
if (DestTy->isAnyCharacterType() || DestTy->isVoidType() ||
    SrcTy->isAnyCharacterType() || SrcTy->isVoidType()) {
  return;
}
// or one of the types is a tag type.
if (SrcTy->getAs<TagType>() || DestTy->getAs<TagType>()) {
  return;
}

// FIXME: Scoped enums?
if ((SrcTy->isUnsignedIntegerType() && DestTy->isSignedIntegerType()) ||
    (SrcTy->isSignedIntegerType() && DestTy->isUnsignedIntegerType())) {
  if (Context.getTypeSize(DestTy) == Context.getTypeSize(SrcTy)) {
    return;
  }
}

Diag(Range.getBegin(), DiagID) << SrcType << DestType << Range;
1927}

1929static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr,
                                QualType DestType) {
QualType SrcType = SrcExpr.get()->getType();
if (Self.Context.hasSameType(SrcType, DestType))
  return;
if (const PointerType *SrcPtrTy = SrcType->getAs<PointerType>())
  if (SrcPtrTy->isObjCSelType()) {
    QualType DT = DestType;
    if (isa<PointerType>(DestType))
      DT = DestType->getPointeeType();
    if (!DT.getUnqualifiedType()->isVoidType())
      Self.Diag(SrcExpr.get()->getExprLoc(),
                diag::warn_cast_pointer_from_sel)
      << SrcType << DestType << SrcExpr.get()->getSourceRange();
  }
1944}

1946/// Diagnose casts that change the calling convention of a pointer to a function
1947/// defined in the current TU.
1948static void DiagnoseCallingConvCast(Sema &Self, const ExprResult &SrcExpr,
                                  QualType DstType, SourceRange OpRange) {
// Check if this cast would change the calling convention of a function
// pointer type.
QualType SrcType = SrcExpr.get()->getType();
if (Self.Context.hasSameType(SrcType, DstType) ||
    !SrcType->isFunctionPointerType() || !DstType->isFunctionPointerType())
  return;
const auto *SrcFTy =
    SrcType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
const auto *DstFTy =
    DstType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
CallingConv SrcCC = SrcFTy->getCallConv();
CallingConv DstCC = DstFTy->getCallConv();
if (SrcCC == DstCC)
  return;

// We have a calling convention cast. Check if the source is a pointer to a
// known, specific function that has already been defined.
Expr *Src = SrcExpr.get()->IgnoreParenImpCasts();
if (auto *UO = dyn_cast<UnaryOperator>(Src))
  if (UO->getOpcode() == UO_AddrOf)
    Src = UO->getSubExpr()->IgnoreParenImpCasts();
auto *DRE = dyn_cast<DeclRefExpr>(Src);
if (!DRE)
  return;
auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
if (!FD)
  return;

// Only warn if we are casting from the default convention to a non-default
// convention. This can happen when the programmer forgot to apply the calling
// convention to the function declaration and then inserted this cast to
// satisfy the type system.
CallingConv DefaultCC = Self.getASTContext().getDefaultCallingConvention(
    FD->isVariadic(), FD->isCXXInstanceMember());
if (DstCC == DefaultCC || SrcCC != DefaultCC)
  return;

// Diagnose this cast, as it is probably bad.
StringRef SrcCCName = FunctionType::getNameForCallConv(SrcCC);
StringRef DstCCName = FunctionType::getNameForCallConv(DstCC);
Self.Diag(OpRange.getBegin(), diag::warn_cast_calling_conv)
    << SrcCCName << DstCCName << OpRange;

// The checks above are cheaper than checking if the diagnostic is enabled.
// However, it's worth checking if the warning is enabled before we construct
// a fixit.
if (Self.Diags.isIgnored(diag::warn_cast_calling_conv, OpRange.getBegin()))
  return;

// Try to suggest a fixit to change the calling convention of the function
// whose address was taken. Try to use the latest macro for the convention.
// For example, users probably want to write "WINAPI" instead of "__stdcall"
// to match the Windows header declarations.
SourceLocation NameLoc = FD->getFirstDecl()->getNameInfo().getLoc();
Preprocessor &PP = Self.getPreprocessor();
SmallVector<TokenValue, 6> AttrTokens;
SmallString<64> CCAttrText;
llvm::raw_svector_ostream OS(CCAttrText);
if (Self.getLangOpts().MicrosoftExt) {
  // __stdcall or __vectorcall
  OS << "__" << DstCCName;
  IdentifierInfo *II = PP.getIdentifierInfo(OS.str());
  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
                           ? TokenValue(II->getTokenID())
                           : TokenValue(II));
} else {
  // __attribute__((stdcall)) or __attribute__((vectorcall))
  OS << "__attribute__((" << DstCCName << "))";
  AttrTokens.push_back(tok::kw___attribute);
  AttrTokens.push_back(tok::l_paren);
  AttrTokens.push_back(tok::l_paren);
  IdentifierInfo *II = PP.getIdentifierInfo(DstCCName);
  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
                           ? TokenValue(II->getTokenID())
                           : TokenValue(II));
  AttrTokens.push_back(tok::r_paren);
  AttrTokens.push_back(tok::r_paren);
}
StringRef AttrSpelling = PP.getLastMacroWithSpelling(NameLoc, AttrTokens);
if (!AttrSpelling.empty())
  CCAttrText = AttrSpelling;
OS << ' ';
Self.Diag(NameLoc, diag::note_change_calling_conv_fixit)
    << FD << DstCCName << FixItHint::CreateInsertion(NameLoc, CCAttrText);
2034}

2036static void checkIntToPointerCast(bool CStyle, const SourceRange &OpRange,
                                const Expr *SrcExpr, QualType DestType,
                                Sema &Self) {
QualType SrcType = SrcExpr->getType();

// Not warning on reinterpret_cast, boolean, constant expressions, etc
// are not explicit design choices, but consistent with GCC's behavior.
// Feel free to modify them if you've reason/evidence for an alternative.
if (CStyle && SrcType->isIntegralType(Self.Context)
    && !SrcType->isBooleanType()
    && !SrcType->isEnumeralType()
    && !SrcExpr->isIntegerConstantExpr(Self.Context)
    && Self.Context.getTypeSize(DestType) >
       Self.Context.getTypeSize(SrcType)) {
  // Separate between casts to void* and non-void* pointers.
  // Some APIs use (abuse) void* for something like a user context,
  // and often that value is an integer even if it isn't a pointer itself.
  // Having a separate warning flag allows users to control the warning
  // for their workflow.
  unsigned Diag = DestType->isVoidPointerType() ?
                    diag::warn_int_to_void_pointer_cast
                  : diag::warn_int_to_pointer_cast;
  Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
}
2060}

2062static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType,
                                           ExprResult &Result) {
// We can only fix an overloaded reinterpret_cast if
// - it is a template with explicit arguments that resolves to an lvalue
//   unambiguously, or
// - it is the only function in an overload set that may have its address
//   taken.

Expr *E = Result.get();
// TODO: what if this fails because of DiagnoseUseOfDecl or something
// like it?
if (Self.ResolveAndFixSingleFunctionTemplateSpecialization(
        Result,
        Expr::getValueKindForType(DestType) == VK_RValue // Convert Fun to Ptr
        ) &&
    Result.isUsable())
  return true;

// No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
// preserves Result.
Result = E;
if (!Self.resolveAndFixAddressOfSingleOverloadCandidate(
        Result, /*DoFunctionPointerConversion=*/true))
  return false;
return Result.isUsable();
2087}

2089static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
                                      QualType DestType, bool CStyle,
                                      SourceRange OpRange,
                                      unsigned &msg,
                                      CastKind &Kind) {
bool IsLValueCast = false;

DestType = Self.Context.getCanonicalType(DestType);
QualType SrcType = SrcExpr.get()->getType();

// Is the source an overloaded name? (i.e. &foo)
// If so, reinterpret_cast generally can not help us here (13.4, p1, bullet 5)
if (SrcType == Self.Context.OverloadTy) {
  ExprResult FixedExpr = SrcExpr;
  if (!fixOverloadedReinterpretCastExpr(Self, DestType, FixedExpr))
    return TC_NotApplicable;

  assert(FixedExpr.isUsable() && "Invalid result fixing overloaded expr")((FixedExpr.isUsable() && "Invalid result fixing overloaded expr"
) ? static_cast<void> (0) : __assert_fail ("FixedExpr.isUsable() && \"Invalid result fixing overloaded expr\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2106, __PRETTY_FUNCTION__));
  SrcExpr = FixedExpr;
  SrcType = SrcExpr.get()->getType();
}

if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
  if (!SrcExpr.get()->isGLValue()) {
    // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
    // similar comment in const_cast.
    msg = diag::err_bad_cxx_cast_rvalue;
    return TC_NotApplicable;
  }

  if (!CStyle) {
    Self.CheckCompatibleReinterpretCast(SrcType, DestType,
                                        /*IsDereference=*/false, OpRange);
  }

  // C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
  //   same effect as the conversion *reinterpret_cast<T*>(&x) with the
  //   built-in & and * operators.

  const char *inappropriate = nullptr;
  switch (SrcExpr.get()->getObjectKind()) {
  case OK_Ordinary:
    break;
  case OK_BitField:
    msg = diag::err_bad_cxx_cast_bitfield;
    return TC_NotApplicable;
    // FIXME: Use a specific diagnostic for the rest of these cases.
  case OK_VectorComponent: inappropriate = "vector element";      break;
  case OK_MatrixComponent:
    inappropriate = "matrix element";
    break;
  case OK_ObjCProperty:    inappropriate = "property expression"; break;
  case OK_ObjCSubscript:   inappropriate = "container subscripting expression";
                           break;
  }
  if (inappropriate) {
    Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
        << inappropriate << DestType
        << OpRange << SrcExpr.get()->getSourceRange();
    msg = 0; SrcExpr = ExprError();
    return TC_NotApplicable;
  }

  // This code does this transformation for the checked types.
  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
  SrcType = Self.Context.getPointerType(SrcType);

  IsLValueCast = true;
}

// Canonicalize source for comparison.
SrcType = Self.Context.getCanonicalType(SrcType);

const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>(),
                        *SrcMemPtr = SrcType->getAs<MemberPointerType>();
if (DestMemPtr && SrcMemPtr) {
  // C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
  //   can be explicitly converted to an rvalue of type "pointer to member
  //   of Y of type T2" if T1 and T2 are both function types or both object
  //   types.
  if (DestMemPtr->isMemberFunctionPointer() !=
      SrcMemPtr->isMemberFunctionPointer())
    return TC_NotApplicable;

  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
    // We need to determine the inheritance model that the class will use if
    // haven't yet.
    (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
    (void)Self.isCompleteType(OpRange.getBegin(), DestType);
  }

  // Don't allow casting between member pointers of different sizes.
  if (Self.Context.getTypeSize(DestMemPtr) !=
      Self.Context.getTypeSize(SrcMemPtr)) {
    msg = diag::err_bad_cxx_cast_member_pointer_size;
    return TC_Failed;
  }

  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
  //   constness.
  // A reinterpret_cast followed by a const_cast can, though, so in C-style,
  // we accept it.
  if (auto CACK =
          CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
                             /*CheckObjCLifetime=*/CStyle))
    return getCastAwayConstnessCastKind(CACK, msg);

  // A valid member pointer cast.
  assert(!IsLValueCast)((!IsLValueCast) ? static_cast<void> (0) : __assert_fail
 ("!IsLValueCast", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2197, __PRETTY_FUNCTION__));
  Kind = CK_ReinterpretMemberPointer;
  return TC_Success;
}

// See below for the enumeral issue.
if (SrcType->isNullPtrType() && DestType->isIntegralType(Self.Context)) {
  // C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
  //   type large enough to hold it. A value of std::nullptr_t can be
  //   converted to an integral type; the conversion has the same meaning
  //   and validity as a conversion of (void*)0 to the integral type.
  if (Self.Context.getTypeSize(SrcType) >
      Self.Context.getTypeSize(DestType)) {
    msg = diag::err_bad_reinterpret_cast_small_int;
    return TC_Failed;
  }
  Kind = CK_PointerToIntegral;
  return TC_Success;
}

// Allow reinterpret_casts between vectors of the same size and
// between vectors and integers of the same size.
bool destIsVector = DestType->isVectorType();
bool srcIsVector = SrcType->isVectorType();
if (srcIsVector || destIsVector) {
  // The non-vector type, if any, must have integral type.  This is
  // the same rule that C vector casts use; note, however, that enum
  // types are not integral in C++.
  if ((!destIsVector && !DestType->isIntegralType(Self.Context)) ||
      (!srcIsVector && !SrcType->isIntegralType(Self.Context)))
    return TC_NotApplicable;

  // The size we want to consider is eltCount * eltSize.
  // That's exactly what the lax-conversion rules will check.
  if (Self.areLaxCompatibleVectorTypes(SrcType, DestType)) {
    Kind = CK_BitCast;
    return TC_Success;
  }

  // Otherwise, pick a reasonable diagnostic.
  if (!destIsVector)
    msg = diag::err_bad_cxx_cast_vector_to_scalar_different_size;
  else if (!srcIsVector)
    msg = diag::err_bad_cxx_cast_scalar_to_vector_different_size;
  else
    msg = diag::err_bad_cxx_cast_vector_to_vector_different_size;

  return TC_Failed;
}

if (SrcType == DestType) {
  // C++ 5.2.10p2 has a note that mentions that, subject to all other
  // restrictions, a cast to the same type is allowed so long as it does not
  // cast away constness. In C++98, the intent was not entirely clear here,
  // since all other paragraphs explicitly forbid casts to the same type.
  // C++11 clarifies this case with p2.
  //
  // The only allowed types are: integral, enumeration, pointer, or
  // pointer-to-member types.  We also won't restrict Obj-C pointers either.
  Kind = CK_NoOp;
  TryCastResult Result = TC_NotApplicable;
  if (SrcType->isIntegralOrEnumerationType() ||
      SrcType->isAnyPointerType() ||
      SrcType->isMemberPointerType() ||
      SrcType->isBlockPointerType()) {
    Result = TC_Success;
  }
  return Result;
}

bool destIsPtr = DestType->isAnyPointerType() ||
                 DestType->isBlockPointerType();
bool srcIsPtr = SrcType->isAnyPointerType() ||
                SrcType->isBlockPointerType();
if (!destIsPtr && !srcIsPtr) {
  // Except for std::nullptr_t->integer and lvalue->reference, which are
  // handled above, at least one of the two arguments must be a pointer.
  return TC_NotApplicable;
}

if (DestType->isIntegralType(Self.Context)) {
  assert(srcIsPtr && "One type must be a pointer")((srcIsPtr && "One type must be a pointer") ? static_cast
<void> (0) : __assert_fail ("srcIsPtr && \"One type must be a pointer\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2278, __PRETTY_FUNCTION__));
  // C++ 5.2.10p4: A pointer can be explicitly converted to any integral
  //   type large enough to hold it; except in Microsoft mode, where the
  //   integral type size doesn't matter (except we don't allow bool).
  if ((Self.Context.getTypeSize(SrcType) >
       Self.Context.getTypeSize(DestType))) {
    bool MicrosoftException =
        Self.getLangOpts().MicrosoftExt && !DestType->isBooleanType();
    if (MicrosoftException) {
      unsigned Diag = SrcType->isVoidPointerType()
                          ? diag::warn_void_pointer_to_int_cast
                          : diag::warn_pointer_to_int_cast;
      Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
    } else {
      msg = diag::err_bad_reinterpret_cast_small_int;
      return TC_Failed;
    }
  }
  Kind = CK_PointerToIntegral;
  return TC_Success;
}

if (SrcType->isIntegralOrEnumerationType()) {
  assert(destIsPtr && "One type must be a pointer")((destIsPtr && "One type must be a pointer") ? static_cast
<void> (0) : __assert_fail ("destIsPtr && \"One type must be a pointer\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2301, __PRETTY_FUNCTION__));
  checkIntToPointerCast(CStyle, OpRange, SrcExpr.get(), DestType, Self);
  // C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
  //   converted to a pointer.
  // C++ 5.2.10p9: [Note: ...a null pointer constant of integral type is not
  //   necessarily converted to a null pointer value.]
  Kind = CK_IntegralToPointer;
  return TC_Success;
}

if (!destIsPtr || !srcIsPtr) {
  // With the valid non-pointer conversions out of the way, we can be even
  // more stringent.
  return TC_NotApplicable;
}

// Cannot convert between block pointers and Objective-C object pointers.
if ((SrcType->isBlockPointerType() && DestType->isObjCObjectPointerType()) ||
    (DestType->isBlockPointerType() && SrcType->isObjCObjectPointerType()))
  return TC_NotApplicable;

// C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
// The C-style cast operator can.
TryCastResult SuccessResult = TC_Success;
if (auto CACK =
        CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
                           /*CheckObjCLifetime=*/CStyle))
  SuccessResult = getCastAwayConstnessCastKind(CACK, msg);

if (IsAddressSpaceConversion(SrcType, DestType)) {
  Kind = CK_AddressSpaceConversion;
  assert(SrcType->isPointerType() && DestType->isPointerType())((SrcType->isPointerType() && DestType->isPointerType
()) ? static_cast<void> (0) : __assert_fail ("SrcType->isPointerType() && DestType->isPointerType()"
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2332, __PRETTY_FUNCTION__));
  if (!CStyle &&
      !DestType->getPointeeType().getQualifiers().isAddressSpaceSupersetOf(
          SrcType->getPointeeType().getQualifiers())) {
    SuccessResult = TC_Failed;
  }
} else if (IsLValueCast) {
  Kind = CK_LValueBitCast;
} else if (DestType->isObjCObjectPointerType()) {
  Kind = Self.PrepareCastToObjCObjectPointer(SrcExpr);
} else if (DestType->isBlockPointerType()) {
  if (!SrcType->isBlockPointerType()) {
    Kind = CK_AnyPointerToBlockPointerCast;
  } else {
    Kind = CK_BitCast;
  }
} else {
  Kind = CK_BitCast;
}

// Any pointer can be cast to an Objective-C pointer type with a C-style
// cast.
if (CStyle && DestType->isObjCObjectPointerType()) {
  return SuccessResult;
}
if (CStyle)
  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);

DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);

// Not casting away constness, so the only remaining check is for compatible
// pointer categories.

if (SrcType->isFunctionPointerType()) {
  if (DestType->isFunctionPointerType()) {
    // C++ 5.2.10p6: A pointer to a function can be explicitly converted to
    // a pointer to a function of a different type.
    return SuccessResult;
  }

  // C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
  //   an object type or vice versa is conditionally-supported.
  // Compilers support it in C++03 too, though, because it's necessary for
  // casting the return value of dlsym() and GetProcAddress().
  // FIXME: Conditionally-supported behavior should be configurable in the
  // TargetInfo or similar.
  Self.Diag(OpRange.getBegin(),
            Self.getLangOpts().CPlusPlus11 ?
              diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
    << OpRange;
  return SuccessResult;
}

if (DestType->isFunctionPointerType()) {
  // See above.
  Self.Diag(OpRange.getBegin(),
            Self.getLangOpts().CPlusPlus11 ?
              diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
    << OpRange;
  return SuccessResult;
}

// Diagnose address space conversion in nested pointers.
QualType DestPtee = DestType->getPointeeType().isNull()
                        ? DestType->getPointeeType()
                        : DestType->getPointeeType()->getPointeeType();
QualType SrcPtee = SrcType->getPointeeType().isNull()
                       ? SrcType->getPointeeType()
                       : SrcType->getPointeeType()->getPointeeType();
while (!DestPtee.isNull() && !SrcPtee.isNull()) {
  if (DestPtee.getAddressSpace() != SrcPtee.getAddressSpace()) {
    Self.Diag(OpRange.getBegin(),
              diag::warn_bad_cxx_cast_nested_pointer_addr_space)
        << CStyle << SrcType << DestType << SrcExpr.get()->getSourceRange();
    break;
  }
  DestPtee = DestPtee->getPointeeType();
  SrcPtee = SrcPtee->getPointeeType();
}

// C++ 5.2.10p7: A pointer to an object can be explicitly converted to
//   a pointer to an object of different type.
// Void pointers are not specified, but supported by every compiler out there.
// So we finish by allowing everything that remains - it's got to be two
// object pointers.
return SuccessResult;
2418}

2420static TryCastResult TryAddressSpaceCast(Sema &Self, ExprResult &SrcExpr,
                                       QualType DestType, bool CStyle,
                                       unsigned &msg, CastKind &Kind) {
if (!Self.getLangOpts().OpenCL)
  // FIXME: As compiler doesn't have any information about overlapping addr
  // spaces at the moment we have to be permissive here.
  return TC_NotApplicable;
// Even though the logic below is general enough and can be applied to
// non-OpenCL mode too, we fast-path above because no other languages
// define overlapping address spaces currently.
auto SrcType = SrcExpr.get()->getType();
// FIXME: Should this be generalized to references? The reference parameter
// however becomes a reference pointee type here and therefore rejected.
// Perhaps this is the right behavior though according to C++.
auto SrcPtrType = SrcType->getAs<PointerType>();
if (!SrcPtrType)
  return TC_NotApplicable;
auto DestPtrType = DestType->getAs<PointerType>();
if (!DestPtrType)
  return TC_NotApplicable;
auto SrcPointeeType = SrcPtrType->getPointeeType();
auto DestPointeeType = DestPtrType->getPointeeType();
if (!DestPointeeType.isAddressSpaceOverlapping(SrcPointeeType)) {
  msg = diag::err_bad_cxx_cast_addr_space_mismatch;
  return TC_Failed;
}
auto SrcPointeeTypeWithoutAS =
    Self.Context.removeAddrSpaceQualType(SrcPointeeType.getCanonicalType());
auto DestPointeeTypeWithoutAS =
    Self.Context.removeAddrSpaceQualType(DestPointeeType.getCanonicalType());
if (Self.Context.hasSameType(SrcPointeeTypeWithoutAS,
                             DestPointeeTypeWithoutAS)) {
  Kind = SrcPointeeType.getAddressSpace() == DestPointeeType.getAddressSpace()
             ? CK_NoOp
             : CK_AddressSpaceConversion;
  return TC_Success;
} else {
  return TC_NotApplicable;
}
2459}

2461void CastOperation::checkAddressSpaceCast(QualType SrcType, QualType DestType) {
// In OpenCL only conversions between pointers to objects in overlapping
// addr spaces are allowed. v2.0 s6.5.5 - Generic addr space overlaps
// with any named one, except for constant.

// Converting the top level pointee addrspace is permitted for compatible
// addrspaces (such as 'generic int *' to 'local int *' or vice versa), but
// if any of the nested pointee addrspaces differ, we emit a warning
// regardless of addrspace compatibility. This makes
//   local int ** p;
//   return (generic int **) p;
// warn even though local -> generic is permitted.
if (Self.getLangOpts().OpenCL) {
  const Type *DestPtr, *SrcPtr;
  bool Nested = false;
  unsigned DiagID = diag::err_typecheck_incompatible_address_space;
  DestPtr = Self.getASTContext().getCanonicalType(DestType.getTypePtr()),
  SrcPtr  = Self.getASTContext().getCanonicalType(SrcType.getTypePtr());

  while (isa<PointerType>(DestPtr) && isa<PointerType>(SrcPtr)) {
    const PointerType *DestPPtr = cast<PointerType>(DestPtr);
    const PointerType *SrcPPtr = cast<PointerType>(SrcPtr);
    QualType DestPPointee = DestPPtr->getPointeeType();
    QualType SrcPPointee = SrcPPtr->getPointeeType();
    if (Nested
            ? DestPPointee.getAddressSpace() != SrcPPointee.getAddressSpace()
            : !DestPPointee.isAddressSpaceOverlapping(SrcPPointee)) {
      Self.Diag(OpRange.getBegin(), DiagID)
          << SrcType << DestType << Sema::AA_Casting
          << SrcExpr.get()->getSourceRange();
      if (!Nested)
        SrcExpr = ExprError();
      return;
    }

    DestPtr = DestPPtr->getPointeeType().getTypePtr();
    SrcPtr = SrcPPtr->getPointeeType().getTypePtr();
    Nested = true;
    DiagID = diag::ext_nested_pointer_qualifier_mismatch;
  }
}
2502}

2504void CastOperation::CheckCXXCStyleCast(bool FunctionalStyle,
                                     bool ListInitialization) {
assert(Self.getLangOpts().CPlusPlus)((Self.getLangOpts().CPlusPlus) ? static_cast<void> (0)
 : __assert_fail ("Self.getLangOpts().CPlusPlus", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2506, __PRETTY_FUNCTION__));

// Handle placeholders.
if (isPlaceholder()) {
  // C-style casts can resolve __unknown_any types.
  if (claimPlaceholder(BuiltinType::UnknownAny)) {
    SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
                                       SrcExpr.get(), Kind,
                                       ValueKind, BasePath);
    return;
  }

  checkNonOverloadPlaceholders();
  if (SrcExpr.isInvalid())
    return;
}

// C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
// This test is outside everything else because it's the only case where
// a non-lvalue-reference target type does not lead to decay.
if (DestType->isVoidType()) {
  Kind = CK_ToVoid;

  if (claimPlaceholder(BuiltinType::Overload)) {
    Self.ResolveAndFixSingleFunctionTemplateSpecialization(
                SrcExpr, /* Decay Function to ptr */ false,
                /* Complain */ true, DestRange, DestType,
                diag::err_bad_cstyle_cast_overload);
    if (SrcExpr.isInvalid())
      return;
  }

  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
  return;
}

// If the type is dependent, we won't do any other semantic analysis now.
if (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
    SrcExpr.get()->isValueDependent()) {
  assert(Kind == CK_Dependent)((Kind == CK_Dependent) ? static_cast<void> (0) : __assert_fail
 ("Kind == CK_Dependent", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2545, __PRETTY_FUNCTION__));
  return;
}

if (ValueKind == VK_RValue && !DestType->isRecordType() &&
    !isPlaceholder(BuiltinType::Overload)) {
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
  if (SrcExpr.isInvalid())
    return;
}

// AltiVec vector initialization with a single literal.
if (const VectorType *vecTy = DestType->getAs<VectorType>())
  if (vecTy->getVectorKind() == VectorType::AltiVecVector
      && (SrcExpr.get()->getType()->isIntegerType()
          || SrcExpr.get()->getType()->isFloatingType())) {
    Kind = CK_VectorSplat;
    SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
    return;
  }

// C++ [expr.cast]p5: The conversions performed by
//   - a const_cast,
//   - a static_cast,
//   - a static_cast followed by a const_cast,
//   - a reinterpret_cast, or
//   - a reinterpret_cast followed by a const_cast,
//   can be performed using the cast notation of explicit type conversion.
//   [...] If a conversion can be interpreted in more than one of the ways
//   listed above, the interpretation that appears first in the list is used,
//   even if a cast resulting from that interpretation is ill-formed.
// In plain language, this means trying a const_cast ...
// Note that for address space we check compatibility after const_cast.
unsigned msg = diag::err_bad_cxx_cast_generic;
TryCastResult tcr = TryConstCast(Self, SrcExpr, DestType,
                                 /*CStyle*/ true, msg);
if (SrcExpr.isInvalid())
  return;
if (isValidCast(tcr))
  Kind = CK_NoOp;

Sema::CheckedConversionKind CCK =
    FunctionalStyle ? Sema::CCK_FunctionalCast : Sema::CCK_CStyleCast;
if (tcr == TC_NotApplicable) {
  tcr = TryAddressSpaceCast(Self, SrcExpr, DestType, /*CStyle*/ true, msg,
                            Kind);
  if (SrcExpr.isInvalid())
    return;

  if (tcr == TC_NotApplicable) {
    // ... or if that is not possible, a static_cast, ignoring const and
    // addr space, ...
    tcr = TryStaticCast(Self, SrcExpr, DestType, CCK, OpRange, msg, Kind,
                        BasePath, ListInitialization);
    if (SrcExpr.isInvalid())
      return;

    if (tcr == TC_NotApplicable) {
      // ... and finally a reinterpret_cast, ignoring const and addr space.
      tcr = TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/ true,
                               OpRange, msg, Kind);
      if (SrcExpr.isInvalid())
        return;
    }
  }
}

if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
    isValidCast(tcr))
  checkObjCConversion(CCK);

if (tcr != TC_Success && msg != 0) {
  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
    DeclAccessPair Found;
    FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
                              DestType,
                              /*Complain*/ true,
                              Found);
    if (Fn) {
      // If DestType is a function type (not to be confused with the function
      // pointer type), it will be possible to resolve the function address,
      // but the type cast should be considered as failure.
      OverloadExpr *OE = OverloadExpr::find(SrcExpr.get()).Expression;
      Self.Diag(OpRange.getBegin(), diag::err_bad_cstyle_cast_overload)
        << OE->getName() << DestType << OpRange
        << OE->getQualifierLoc().getSourceRange();
      Self.NoteAllOverloadCandidates(SrcExpr.get());
    }
  } else {
    diagnoseBadCast(Self, msg, (FunctionalStyle ? CT_Functional : CT_CStyle),
                    OpRange, SrcExpr.get(), DestType, ListInitialization);
  }
}

if (isValidCast(tcr)) {
  if (Kind == CK_BitCast)
    checkCastAlign();
} else {
  SrcExpr = ExprError();
}
2645}

2647/// DiagnoseBadFunctionCast - Warn whenever a function call is cast to a
2648///  non-matching type. Such as enum function call to int, int call to
2649/// pointer; etc. Cast to 'void' is an exception.
2650static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr,
                                QualType DestType) {
if (Self.Diags.isIgnored(diag::warn_bad_function_cast,
                         SrcExpr.get()->getExprLoc()))
  return;

if (!isa<CallExpr>(SrcExpr.get()))
  return;

QualType SrcType = SrcExpr.get()->getType();
if (DestType.getUnqualifiedType()->isVoidType())
  return;
if ((SrcType->isAnyPointerType() || SrcType->isBlockPointerType())
    && (DestType->isAnyPointerType() || DestType->isBlockPointerType()))
  return;
if (SrcType->isIntegerType() && DestType->isIntegerType() &&
    (SrcType->isBooleanType() == DestType->isBooleanType()) &&
    (SrcType->isEnumeralType() == DestType->isEnumeralType()))
  return;
if (SrcType->isRealFloatingType() && DestType->isRealFloatingType())
  return;
if (SrcType->isEnumeralType() && DestType->isEnumeralType())
  return;
if (SrcType->isComplexType() && DestType->isComplexType())
  return;
if (SrcType->isComplexIntegerType() && DestType->isComplexIntegerType())
  return;
if (SrcType->isFixedPointType() && DestType->isFixedPointType())
  return;

Self.Diag(SrcExpr.get()->getExprLoc(),
          diag::warn_bad_function_cast)
          << SrcType << DestType << SrcExpr.get()->getSourceRange();
2683}

2685/// Check the semantics of a C-style cast operation, in C.
2686void CastOperation::CheckCStyleCast() {
assert(!Self.getLangOpts().CPlusPlus)((!Self.getLangOpts().CPlusPlus) ? static_cast<void> (0
) : __assert_fail ("!Self.getLangOpts().CPlusPlus", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2687, __PRETTY_FUNCTION__));

// C-style casts can resolve __unknown_any types.
if (claimPlaceholder(BuiltinType::UnknownAny)) {
  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
                                     SrcExpr.get(), Kind,
                                     ValueKind, BasePath);
  return;
}

// C99 6.5.4p2: the cast type needs to be void or scalar and the expression
// type needs to be scalar.
if (DestType->isVoidType()) {
  // We don't necessarily do lvalue-to-rvalue conversions on this.
  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
  if (SrcExpr.isInvalid())
    return;

  // Cast to void allows any expr type.
  Kind = CK_ToVoid;
  return;
}

// Overloads are allowed with C extensions, so we need to support them.
if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
  DeclAccessPair DAP;
  if (FunctionDecl *FD = Self.ResolveAddressOfOverloadedFunction(
          SrcExpr.get(), DestType, /*Complain=*/true, DAP))
    SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr.get(), DAP, FD);
  else
    return;
  assert(SrcExpr.isUsable())((SrcExpr.isUsable()) ? static_cast<void> (0) : __assert_fail
 ("SrcExpr.isUsable()", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2718, __PRETTY_FUNCTION__));
}
SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
if (SrcExpr.isInvalid())
  return;
QualType SrcType = SrcExpr.get()->getType();

assert(!SrcType->isPlaceholderType())((!SrcType->isPlaceholderType()) ? static_cast<void>
 (0) : __assert_fail ("!SrcType->isPlaceholderType()", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 2725, __PRETTY_FUNCTION__));

checkAddressSpaceCast(SrcType, DestType);
if (SrcExpr.isInvalid())
  return;

if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
                             diag::err_typecheck_cast_to_incomplete)) {
  SrcExpr = ExprError();
  return;
}

// Allow casting a sizeless built-in type to itself.
if (DestType->isSizelessBuiltinType() &&
    Self.Context.hasSameUnqualifiedType(DestType, SrcType)) {
  Kind = CK_NoOp;
  return;
}

if (!DestType->isScalarType() && !DestType->isVectorType()) {
  const RecordType *DestRecordTy = DestType->getAs<RecordType>();

  if (DestRecordTy && Self.Context.hasSameUnqualifiedType(DestType, SrcType)){
    // GCC struct/union extension: allow cast to self.
    Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_nonscalar)
      << DestType << SrcExpr.get()->getSourceRange();
    Kind = CK_NoOp;
    return;
  }

  // GCC's cast to union extension.
  if (DestRecordTy && DestRecordTy->getDecl()->isUnion()) {
    RecordDecl *RD = DestRecordTy->getDecl();
    if (CastExpr::getTargetFieldForToUnionCast(RD, SrcType)) {
      Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_to_union)
        << SrcExpr.get()->getSourceRange();
      Kind = CK_ToUnion;
      return;
    } else {
      Self.Diag(OpRange.getBegin(), diag::err_typecheck_cast_to_union_no_type)
        << SrcType << SrcExpr.get()->getSourceRange();
      SrcExpr = ExprError();
      return;
    }
  }

  // OpenCL v2.0 s6.13.10 - Allow casts from '0' to event_t type.
  if (Self.getLangOpts().OpenCL && DestType->isEventT()) {
    Expr::EvalResult Result;
    if (SrcExpr.get()->EvaluateAsInt(Result, Self.Context)) {
      llvm::APSInt CastInt = Result.Val.getInt();
      if (0 == CastInt) {
        Kind = CK_ZeroToOCLOpaqueType;
        return;
      }
      Self.Diag(OpRange.getBegin(),
                diag::err_opencl_cast_non_zero_to_event_t)
                << CastInt.toString(10) << SrcExpr.get()->getSourceRange();
      SrcExpr = ExprError();
      return;
    }
  }

  // Reject any other conversions to non-scalar types.
  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cond_expect_scalar)
    << DestType << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

// The type we're casting to is known to be a scalar or vector.

// Require the operand to be a scalar or vector.
if (!SrcType->isScalarType() && !SrcType->isVectorType()) {
  Self.Diag(SrcExpr.get()->getExprLoc(),
            diag::err_typecheck_expect_scalar_operand)
    << SrcType << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

if (DestType->isExtVectorType()) {
  SrcExpr = Self.CheckExtVectorCast(OpRange, DestType, SrcExpr.get(), Kind);
  return;
}

if (const VectorType *DestVecTy = DestType->getAs<VectorType>()) {
  if (DestVecTy->getVectorKind() == VectorType::AltiVecVector &&
        (SrcType->isIntegerType() || SrcType->isFloatingType())) {
    Kind = CK_VectorSplat;
    SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
  } else if (Self.CheckVectorCast(OpRange, DestType, SrcType, Kind)) {
    SrcExpr = ExprError();
  }
  return;
}

if (SrcType->isVectorType()) {
  if (Self.CheckVectorCast(OpRange, SrcType, DestType, Kind))
    SrcExpr = ExprError();
  return;
}

// The source and target types are both scalars, i.e.
//   - arithmetic types (fundamental, enum, and complex)
//   - all kinds of pointers
// Note that member pointers were filtered out with C++, above.

if (isa<ObjCSelectorExpr>(SrcExpr.get())) {
  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_selector_expr);
  SrcExpr = ExprError();
  return;
}

// Can't cast to or from bfloat
if (DestType->isBFloat16Type() && !SrcType->isBFloat16Type()) {
  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_to_bfloat16)
      << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}
if (SrcType->isBFloat16Type() && !DestType->isBFloat16Type()) {
  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_from_bfloat16)
      << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

// If either type is a pointer, the other type has to be either an
// integer or a pointer.
if (!DestType->isArithmeticType()) {
  if (!SrcType->isIntegralType(Self.Context) && SrcType->isArithmeticType()) {
    Self.Diag(SrcExpr.get()->getExprLoc(),
              diag::err_cast_pointer_from_non_pointer_int)
      << SrcType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
  checkIntToPointerCast(/* CStyle */ true, OpRange, SrcExpr.get(), DestType,
                        Self);
} else if (!SrcType->isArithmeticType()) {
  if (!DestType->isIntegralType(Self.Context) &&
      DestType->isArithmeticType()) {
    Self.Diag(SrcExpr.get()->getBeginLoc(),
              diag::err_cast_pointer_to_non_pointer_int)
        << DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }

  if ((Self.Context.getTypeSize(SrcType) >
       Self.Context.getTypeSize(DestType)) &&
      !DestType->isBooleanType()) {
    // C 6.3.2.3p6: Any pointer type may be converted to an integer type.
    // Except as previously specified, the result is implementation-defined.
    // If the result cannot be represented in the integer type, the behavior
    // is undefined. The result need not be in the range of values of any
    // integer type.
    unsigned Diag;
    if (SrcType->isVoidPointerType())
      Diag = DestType->isEnumeralType() ? diag::warn_void_pointer_to_enum_cast
                                        : diag::warn_void_pointer_to_int_cast;
    else if (DestType->isEnumeralType())
      Diag = diag::warn_pointer_to_enum_cast;
    else
      Diag = diag::warn_pointer_to_int_cast;
    Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
  }
}

if (Self.getLangOpts().OpenCL &&
    !Self.getOpenCLOptions().isEnabled("cl_khr_fp16")) {
  if (DestType->isHalfType()) {
    Self.Diag(SrcExpr.get()->getBeginLoc(), diag::err_opencl_cast_to_half)
        << DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
}

// ARC imposes extra restrictions on casts.
if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers()) {
  checkObjCConversion(Sema::CCK_CStyleCast);
  if (SrcExpr.isInvalid())
    return;

  const PointerType *CastPtr = DestType->getAs<PointerType>();
  if (Self.getLangOpts().ObjCAutoRefCount && CastPtr) {
    if (const PointerType *ExprPtr = SrcType->getAs<PointerType>()) {
      Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers();
      Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers();
      if (CastPtr->getPointeeType()->isObjCLifetimeType() &&
          ExprPtr->getPointeeType()->isObjCLifetimeType() &&
          !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) {
        Self.Diag(SrcExpr.get()->getBeginLoc(),
                  diag::err_typecheck_incompatible_ownership)
            << SrcType << DestType << Sema::AA_Casting
            << SrcExpr.get()->getSourceRange();
        return;
      }
    }
  }
  else if (!Self.CheckObjCARCUnavailableWeakConversion(DestType, SrcType)) {
    Self.Diag(SrcExpr.get()->getBeginLoc(),
              diag::err_arc_convesion_of_weak_unavailable)
        << 1 << SrcType << DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
}

DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
DiagnoseBadFunctionCast(Self, SrcExpr, DestType);
Kind = Self.PrepareScalarCast(SrcExpr, DestType);
if (SrcExpr.isInvalid())
  return;

if (Kind == CK_BitCast)
  checkCastAlign();
2945}

2947void CastOperation::CheckBuiltinBitCast() {
QualType SrcType = SrcExpr.get()->getType();

if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
                             diag::err_typecheck_cast_to_incomplete) ||
    Self.RequireCompleteType(OpRange.getBegin(), SrcType,
                             diag::err_incomplete_type)) {
  SrcExpr = ExprError();
  return;
}

if (SrcExpr.get()->isRValue())
  SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcType, SrcExpr.get(),
                                                /*IsLValueReference=*/false);

CharUnits DestSize = Self.Context.getTypeSizeInChars(DestType);
CharUnits SourceSize = Self.Context.getTypeSizeInChars(SrcType);
if (DestSize != SourceSize) {
  Self.Diag(OpRange.getBegin(), diag::err_bit_cast_type_size_mismatch)
      << (int)SourceSize.getQuantity() << (int)DestSize.getQuantity();
  SrcExpr = ExprError();
  return;
}

if (!DestType.isTriviallyCopyableType(Self.Context)) {
  Self.Diag(OpRange.getBegin(), diag::err_bit_cast_non_trivially_copyable)
      << 1;
  SrcExpr = ExprError();
  return;
}

if (!SrcType.isTriviallyCopyableType(Self.Context)) {
  Self.Diag(OpRange.getBegin(), diag::err_bit_cast_non_trivially_copyable)
      << 0;
  SrcExpr = ExprError();
  return;
}

Kind = CK_LValueToRValueBitCast;
2986}

2988/// DiagnoseCastQual - Warn whenever casts discards a qualifiers, be it either
2989/// const, volatile or both.
2990static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
                           QualType DestType) {
if (SrcExpr.isInvalid())
  return;

QualType SrcType = SrcExpr.get()->getType();
if (!((SrcType->isAnyPointerType() && DestType->isAnyPointerType()) ||
      DestType->isLValueReferenceType()))
  return;

QualType TheOffendingSrcType, TheOffendingDestType;
Qualifiers CastAwayQualifiers;
if (CastsAwayConstness(Self, SrcType, DestType, true, false,
                       &TheOffendingSrcType, &TheOffendingDestType,
                       &CastAwayQualifiers) !=
    CastAwayConstnessKind::CACK_Similar)
  return;

// FIXME: 'restrict' is not properly handled here.
int qualifiers = -1;
if (CastAwayQualifiers.hasConst() && CastAwayQualifiers.hasVolatile()) {
  qualifiers = 0;
} else if (CastAwayQualifiers.hasConst()) {
  qualifiers = 1;
} else if (CastAwayQualifiers.hasVolatile()) {
  qualifiers = 2;
}
// This is a variant of int **x; const int **y = (const int **)x;
if (qualifiers == -1)
  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual2)
      << SrcType << DestType;
else
  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual)
      << TheOffendingSrcType << TheOffendingDestType << qualifiers;
3024}

3026ExprResult Sema::BuildCStyleCastExpr(SourceLocation LPLoc,
                                   TypeSourceInfo *CastTypeInfo,
                                   SourceLocation RPLoc,
                                   Expr *CastExpr) {
CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
Op.OpRange = SourceRange(LPLoc, CastExpr->getEndLoc());

if (getLangOpts().CPlusPlus) {
  Op.CheckCXXCStyleCast(/*FunctionalCast=*/ false,
                        isa<InitListExpr>(CastExpr));
} else {
  Op.CheckCStyleCast();
}

if (Op.SrcExpr.isInvalid())
  return ExprError();

// -Wcast-qual
DiagnoseCastQual(Op.Self, Op.SrcExpr, Op.DestType);

return Op.complete(CStyleCastExpr::Create(
    Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
    &Op.BasePath, CurFPFeatureOverrides(), CastTypeInfo, LPLoc, RPLoc));
3050}

3052ExprResult Sema::BuildCXXFunctionalCastExpr(TypeSourceInfo *CastTypeInfo,
                                          QualType Type,
                                          SourceLocation LPLoc,
                                          Expr *CastExpr,
                                          SourceLocation RPLoc) {
assert(LPLoc.isValid() && "List-initialization shouldn't get here.")((LPLoc.isValid() && "List-initialization shouldn't get here."
) ? static_cast<void> (0) : __assert_fail ("LPLoc.isValid() && \"List-initialization shouldn't get here.\""
, "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/lib/Sema/SemaCast.cpp"
, 3057, __PRETTY_FUNCTION__));
CastOperation Op(*this, Type, CastExpr);
Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
Op.OpRange = SourceRange(Op.DestRange.getBegin(), CastExpr->getEndLoc());

Op.CheckCXXCStyleCast(/*FunctionalCast=*/true, /*ListInit=*/false);
if (Op.SrcExpr.isInvalid())
  return ExprError();

auto *SubExpr = Op.SrcExpr.get();
if (auto *BindExpr = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
  SubExpr = BindExpr->getSubExpr();
if (auto *ConstructExpr = dyn_cast<CXXConstructExpr>(SubExpr))
  ConstructExpr->setParenOrBraceRange(SourceRange(LPLoc, RPLoc));

return Op.complete(CXXFunctionalCastExpr::Create(
    Context, Op.ResultType, Op.ValueKind, CastTypeInfo, Op.Kind,
    Op.SrcExpr.get(), &Op.BasePath, CurFPFeatureOverrides(), LPLoc, RPLoc));
3075}

←

/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h

1	//===- Type.h - C Language Family Type Representation ------------ C++ --===//
2	//
3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4	// See https://llvm.org/LICENSE.txt for license information.
5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6	//
7	//===----------------------------------------------------------------------===//
8	//
9	/// \file
10	/// C Language Family Type Representation
11	///
12	/// This file defines the clang::Type interface and subclasses, used to
13	/// represent types for languages in the C family.
14	//
15	//===----------------------------------------------------------------------===//
16
17	#ifndef LLVM_CLANG_AST_TYPE_H
18	#define LLVM_CLANG_AST_TYPE_H
19
20	#include "clang/AST/DependenceFlags.h"
21	#include "clang/AST/NestedNameSpecifier.h"
22	#include "clang/AST/TemplateName.h"
23	#include "clang/Basic/AddressSpaces.h"
24	#include "clang/Basic/AttrKinds.h"
25	#include "clang/Basic/Diagnostic.h"
26	#include "clang/Basic/ExceptionSpecificationType.h"
27	#include "clang/Basic/LLVM.h"
28	#include "clang/Basic/Linkage.h"
29	#include "clang/Basic/PartialDiagnostic.h"
30	#include "clang/Basic/SourceLocation.h"
31	#include "clang/Basic/Specifiers.h"
32	#include "clang/Basic/Visibility.h"
33	#include "llvm/ADT/APInt.h"
34	#include "llvm/ADT/APSInt.h"
35	#include "llvm/ADT/ArrayRef.h"
36	#include "llvm/ADT/FoldingSet.h"
37	#include "llvm/ADT/None.h"
38	#include "llvm/ADT/Optional.h"
39	#include "llvm/ADT/PointerIntPair.h"
40	#include "llvm/ADT/PointerUnion.h"
41	#include "llvm/ADT/StringRef.h"
42	#include "llvm/ADT/Twine.h"
43	#include "llvm/ADT/iterator_range.h"
44	#include "llvm/Support/Casting.h"
45	#include "llvm/Support/Compiler.h"
46	#include "llvm/Support/ErrorHandling.h"
47	#include "llvm/Support/PointerLikeTypeTraits.h"
48	#include "llvm/Support/TrailingObjects.h"
49	#include "llvm/Support/type_traits.h"
50	#include <cassert>
51	#include <cstddef>
52	#include <cstdint>
53	#include <cstring>
54	#include <string>
55	#include <type_traits>
56	#include <utility>
57
58	namespace clang {
59
60	class ExtQuals;
61	class QualType;
62	class ConceptDecl;
63	class TagDecl;
64	class Type;
65
66	enum {
67	TypeAlignmentInBits = 4,
68	TypeAlignment = 1 << TypeAlignmentInBits
69	};
70
71	namespace serialization {
72	template <class T> class AbstractTypeReader;
73	template <class T> class AbstractTypeWriter;
74	}
75
76	} // namespace clang
77
78	namespace llvm {
79
80	template <typename T>
81	struct PointerLikeTypeTraits;
82	template<>
83	struct PointerLikeTypeTraits< ::clang::Type*> {
84	static inline void getAsVoidPointer(::clang::Type P) { return P; }
85
86	static inline ::clang::Type getFromVoidPointer(void P) {
87	return static_cast< ::clang::Type*>(P);
88	}
89
90	static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
91	};
92
93	template<>
94	struct PointerLikeTypeTraits< ::clang::ExtQuals*> {
95	static inline void getAsVoidPointer(::clang::ExtQuals P) { return P; }
96
97	static inline ::clang::ExtQuals getFromVoidPointer(void P) {
98	return static_cast< ::clang::ExtQuals*>(P);
99	}
100
101	static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
102	};
103
104	} // namespace llvm
105
106	namespace clang {
107
108	class ASTContext;
109	template <typename> class CanQual;
110	class CXXRecordDecl;
111	class DeclContext;
112	class EnumDecl;
113	class Expr;
114	class ExtQualsTypeCommonBase;
115	class FunctionDecl;
116	class IdentifierInfo;
117	class NamedDecl;
118	class ObjCInterfaceDecl;
119	class ObjCProtocolDecl;
120	class ObjCTypeParamDecl;
121	struct PrintingPolicy;
122	class RecordDecl;
123	class Stmt;
124	class TagDecl;
125	class TemplateArgument;
126	class TemplateArgumentListInfo;
127	class TemplateArgumentLoc;
128	class TemplateTypeParmDecl;
129	class TypedefNameDecl;
130	class UnresolvedUsingTypenameDecl;
131
132	using CanQualType = CanQual<Type>;
133
134	// Provide forward declarations for all of the *Type classes.
135	#define TYPE(Class, Base) class Class##Type;
136	#include "clang/AST/TypeNodes.inc"
137
138	/// The collection of all-type qualifiers we support.
139	/// Clang supports five independent qualifiers:
140	/// * C99: const, volatile, and restrict
141	/// * MS: __unaligned
142	/// * Embedded C (TR18037): address spaces
143	/// * Objective C: the GC attributes (none, weak, or strong)
144	class Qualifiers {
145	public:
146	enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
147	Const = 0x1,
148	Restrict = 0x2,
149	Volatile = 0x4,
150	CVRMask = Const \| Volatile \| Restrict
151	};
152
153	enum GC {
154	GCNone = 0,
155	Weak,
156	Strong
157	};
158
159	enum ObjCLifetime {
160	/// There is no lifetime qualification on this type.
161	OCL_None,
162
163	/// This object can be modified without requiring retains or
164	/// releases.
165	OCL_ExplicitNone,
166
167	/// Assigning into this object requires the old value to be
168	/// released and the new value to be retained. The timing of the
169	/// release of the old value is inexact: it may be moved to
170	/// immediately after the last known point where the value is
171	/// live.
172	OCL_Strong,
173
174	/// Reading or writing from this object requires a barrier call.
175	OCL_Weak,
176
177	/// Assigning into this object requires a lifetime extension.
178	OCL_Autoreleasing
179	};
180
181	enum {
182	/// The maximum supported address space number.
183	/// 23 bits should be enough for anyone.
184	MaxAddressSpace = 0x7fffffu,
185
186	/// The width of the "fast" qualifier mask.
187	FastWidth = 3,
188
189	/// The fast qualifier mask.
190	FastMask = (1 << FastWidth) - 1
191	};
192
193	/// Returns the common set of qualifiers while removing them from
194	/// the given sets.
195	static Qualifiers removeCommonQualifiers(Qualifiers &L, Qualifiers &R) {
196	// If both are only CVR-qualified, bit operations are sufficient.
197	if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
198	Qualifiers Q;
199	Q.Mask = L.Mask & R.Mask;
200	L.Mask &= ~Q.Mask;
201	R.Mask &= ~Q.Mask;
202	return Q;
203	}
204
205	Qualifiers Q;
206	unsigned CommonCRV = L.getCVRQualifiers() & R.getCVRQualifiers();
207	Q.addCVRQualifiers(CommonCRV);
208	L.removeCVRQualifiers(CommonCRV);
209	R.removeCVRQualifiers(CommonCRV);
210
211	if (L.getObjCGCAttr() == R.getObjCGCAttr()) {
212	Q.setObjCGCAttr(L.getObjCGCAttr());
213	L.removeObjCGCAttr();
214	R.removeObjCGCAttr();
215	}
216
217	if (L.getObjCLifetime() == R.getObjCLifetime()) {
218	Q.setObjCLifetime(L.getObjCLifetime());
219	L.removeObjCLifetime();
220	R.removeObjCLifetime();
221	}
222
223	if (L.getAddressSpace() == R.getAddressSpace()) {
224	Q.setAddressSpace(L.getAddressSpace());
225	L.removeAddressSpace();
226	R.removeAddressSpace();
227	}
228	return Q;
229	}
230
231	static Qualifiers fromFastMask(unsigned Mask) {
232	Qualifiers Qs;
233	Qs.addFastQualifiers(Mask);
234	return Qs;
235	}
236
237	static Qualifiers fromCVRMask(unsigned CVR) {
238	Qualifiers Qs;
239	Qs.addCVRQualifiers(CVR);
240	return Qs;
241	}
242
243	static Qualifiers fromCVRUMask(unsigned CVRU) {
244	Qualifiers Qs;
245	Qs.addCVRUQualifiers(CVRU);
246	return Qs;
247	}
248
249	// Deserialize qualifiers from an opaque representation.
250	static Qualifiers fromOpaqueValue(unsigned opaque) {
251	Qualifiers Qs;
252	Qs.Mask = opaque;
253	return Qs;
254	}
255
256	// Serialize these qualifiers into an opaque representation.
257	unsigned getAsOpaqueValue() const {
258	return Mask;
259	}
260
261	bool hasConst() const { return Mask & Const; }
262	bool hasOnlyConst() const { return Mask == Const; }
263	void removeConst() { Mask &= ~Const; }
264	void addConst() { Mask \|= Const; }
265
266	bool hasVolatile() const { return Mask & Volatile; }
267	bool hasOnlyVolatile() const { return Mask == Volatile; }
268	void removeVolatile() { Mask &= ~Volatile; }
269	void addVolatile() { Mask \|= Volatile; }
270
271	bool hasRestrict() const { return Mask & Restrict; }
272	bool hasOnlyRestrict() const { return Mask == Restrict; }
273	void removeRestrict() { Mask &= ~Restrict; }
274	void addRestrict() { Mask \|= Restrict; }
275
276	bool hasCVRQualifiers() const { return getCVRQualifiers(); }
277	unsigned getCVRQualifiers() const { return Mask & CVRMask; }
278	unsigned getCVRUQualifiers() const { return Mask & (CVRMask \| UMask); }
279
280	void setCVRQualifiers(unsigned mask) {
281	assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((!(mask & ~CVRMask) && "bitmask contains non-CVR bits" ) ? static_cast<void> (0) : __assert_fail ("!(mask & ~CVRMask) && \"bitmask contains non-CVR bits\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 281, __PRETTY_FUNCTION__));
282	Mask = (Mask & ~CVRMask) \| mask;
283	}
284	void removeCVRQualifiers(unsigned mask) {
285	assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((!(mask & ~CVRMask) && "bitmask contains non-CVR bits" ) ? static_cast<void> (0) : __assert_fail ("!(mask & ~CVRMask) && \"bitmask contains non-CVR bits\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 285, __PRETTY_FUNCTION__));
286	Mask &= ~mask;
287	}
288	void removeCVRQualifiers() {
289	removeCVRQualifiers(CVRMask);
290	}
291	void addCVRQualifiers(unsigned mask) {
292	assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((!(mask & ~CVRMask) && "bitmask contains non-CVR bits" ) ? static_cast<void> (0) : __assert_fail ("!(mask & ~CVRMask) && \"bitmask contains non-CVR bits\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 292, __PRETTY_FUNCTION__));
293	Mask \|= mask;
294	}
295	void addCVRUQualifiers(unsigned mask) {
296	assert(!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits")((!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits" ) ? static_cast<void> (0) : __assert_fail ("!(mask & ~CVRMask & ~UMask) && \"bitmask contains non-CVRU bits\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 296, __PRETTY_FUNCTION__));
297	Mask \|= mask;
298	}
299
300	bool hasUnaligned() const { return Mask & UMask; }
301	void setUnaligned(bool flag) {
302	Mask = (Mask & ~UMask) \| (flag ? UMask : 0);
303	}
304	void removeUnaligned() { Mask &= ~UMask; }
305	void addUnaligned() { Mask \|= UMask; }
306
307	bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
308	GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
309	void setObjCGCAttr(GC type) {
310	Mask = (Mask & ~GCAttrMask) \| (type << GCAttrShift);
311	}
312	void removeObjCGCAttr() { setObjCGCAttr(GCNone); }
313	void addObjCGCAttr(GC type) {
314	assert(type)((type) ? static_cast<void> (0) : __assert_fail ("type" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 314, __PRETTY_FUNCTION__));
315	setObjCGCAttr(type);
316	}
317	Qualifiers withoutObjCGCAttr() const {
318	Qualifiers qs = *this;
319	qs.removeObjCGCAttr();
320	return qs;
321	}
322	Qualifiers withoutObjCLifetime() const {
323	Qualifiers qs = *this;
324	qs.removeObjCLifetime();
325	return qs;
326	}
327	Qualifiers withoutAddressSpace() const {
328	Qualifiers qs = *this;
329	qs.removeAddressSpace();
330	return qs;
331	}
332
333	bool hasObjCLifetime() const { return Mask & LifetimeMask; }
334	ObjCLifetime getObjCLifetime() const {
335	return ObjCLifetime((Mask & LifetimeMask) >> LifetimeShift);
336	}
337	void setObjCLifetime(ObjCLifetime type) {
338	Mask = (Mask & ~LifetimeMask) \| (type << LifetimeShift);
339	}
340	void removeObjCLifetime() { setObjCLifetime(OCL_None); }
341	void addObjCLifetime(ObjCLifetime type) {
342	assert(type)((type) ? static_cast<void> (0) : __assert_fail ("type" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 342, __PRETTY_FUNCTION__));
343	assert(!hasObjCLifetime())((!hasObjCLifetime()) ? static_cast<void> (0) : __assert_fail ("!hasObjCLifetime()", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 343, __PRETTY_FUNCTION__));
344	Mask \|= (type << LifetimeShift);
345	}
346
347	/// True if the lifetime is neither None or ExplicitNone.
348	bool hasNonTrivialObjCLifetime() const {
349	ObjCLifetime lifetime = getObjCLifetime();
350	return (lifetime > OCL_ExplicitNone);
351	}
352
353	/// True if the lifetime is either strong or weak.
354	bool hasStrongOrWeakObjCLifetime() const {
355	ObjCLifetime lifetime = getObjCLifetime();
356	return (lifetime == OCL_Strong \|\| lifetime == OCL_Weak);
357	}
358
359	bool hasAddressSpace() const { return Mask & AddressSpaceMask; }
360	LangAS getAddressSpace() const {
361	return static_cast<LangAS>(Mask >> AddressSpaceShift);
362	}
363	bool hasTargetSpecificAddressSpace() const {
364	return isTargetAddressSpace(getAddressSpace());
365	}
366	/// Get the address space attribute value to be printed by diagnostics.
367	unsigned getAddressSpaceAttributePrintValue() const {
368	auto Addr = getAddressSpace();
369	// This function is not supposed to be used with language specific
370	// address spaces. If that happens, the diagnostic message should consider
371	// printing the QualType instead of the address space value.
372	assert(Addr == LangAS::Default \|\| hasTargetSpecificAddressSpace())((Addr == LangAS::Default \|\| hasTargetSpecificAddressSpace()) ? static_cast<void> (0) : __assert_fail ("Addr == LangAS::Default \|\| hasTargetSpecificAddressSpace()" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 372, __PRETTY_FUNCTION__));
373	if (Addr != LangAS::Default)
374	return toTargetAddressSpace(Addr);
375	// TODO: The diagnostic messages where Addr may be 0 should be fixed
376	// since it cannot differentiate the situation where 0 denotes the default
377	// address space or user specified __attribute__((address_space(0))).
378	return 0;
379	}
380	void setAddressSpace(LangAS space) {
381	assert((unsigned)space <= MaxAddressSpace)(((unsigned)space <= MaxAddressSpace) ? static_cast<void > (0) : __assert_fail ("(unsigned)space <= MaxAddressSpace" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 381, __PRETTY_FUNCTION__));
382	Mask = (Mask & ~AddressSpaceMask)
383	\| (((uint32_t) space) << AddressSpaceShift);
384	}
385	void removeAddressSpace() { setAddressSpace(LangAS::Default); }
386	void addAddressSpace(LangAS space) {
387	assert(space != LangAS::Default)((space != LangAS::Default) ? static_cast<void> (0) : __assert_fail ("space != LangAS::Default", "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 387, __PRETTY_FUNCTION__));
388	setAddressSpace(space);
389	}
390
391	// Fast qualifiers are those that can be allocated directly
392	// on a QualType object.
393	bool hasFastQualifiers() const { return getFastQualifiers(); }
394	unsigned getFastQualifiers() const { return Mask & FastMask; }
395	void setFastQualifiers(unsigned mask) {
396	assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits" ) ? static_cast<void> (0) : __assert_fail ("!(mask & ~FastMask) && \"bitmask contains non-fast qualifier bits\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 396, __PRETTY_FUNCTION__));
397	Mask = (Mask & ~FastMask) \| mask;
398	}
399	void removeFastQualifiers(unsigned mask) {
400	assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits" ) ? static_cast<void> (0) : __assert_fail ("!(mask & ~FastMask) && \"bitmask contains non-fast qualifier bits\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 400, __PRETTY_FUNCTION__));
401	Mask &= ~mask;
402	}
403	void removeFastQualifiers() {
404	removeFastQualifiers(FastMask);
405	}
406	void addFastQualifiers(unsigned mask) {
407	assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits" ) ? static_cast<void> (0) : __assert_fail ("!(mask & ~FastMask) && \"bitmask contains non-fast qualifier bits\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 407, __PRETTY_FUNCTION__));
408	Mask \|= mask;
409	}
410
411	/// Return true if the set contains any qualifiers which require an ExtQuals
412	/// node to be allocated.
413	bool hasNonFastQualifiers() const { return Mask & ~FastMask; }
414	Qualifiers getNonFastQualifiers() const {
415	Qualifiers Quals = *this;
416	Quals.setFastQualifiers(0);
417	return Quals;
418	}
419
420	/// Return true if the set contains any qualifiers.
421	bool hasQualifiers() const { return Mask; }
422	bool empty() const { return !Mask; }
423
424	/// Add the qualifiers from the given set to this set.
425	void addQualifiers(Qualifiers Q) {
426	// If the other set doesn't have any non-boolean qualifiers, just
427	// bit-or it in.
428	if (!(Q.Mask & ~CVRMask))
429	Mask \|= Q.Mask;
430	else {
431	Mask \|= (Q.Mask & CVRMask);
432	if (Q.hasAddressSpace())
433	addAddressSpace(Q.getAddressSpace());
434	if (Q.hasObjCGCAttr())
435	addObjCGCAttr(Q.getObjCGCAttr());
436	if (Q.hasObjCLifetime())
437	addObjCLifetime(Q.getObjCLifetime());
438	}
439	}
440
441	/// Remove the qualifiers from the given set from this set.
442	void removeQualifiers(Qualifiers Q) {
443	// If the other set doesn't have any non-boolean qualifiers, just
444	// bit-and the inverse in.
445	if (!(Q.Mask & ~CVRMask))
446	Mask &= ~Q.Mask;
447	else {
448	Mask &= ~(Q.Mask & CVRMask);
449	if (getObjCGCAttr() == Q.getObjCGCAttr())
450	removeObjCGCAttr();
451	if (getObjCLifetime() == Q.getObjCLifetime())
452	removeObjCLifetime();
453	if (getAddressSpace() == Q.getAddressSpace())
454	removeAddressSpace();
455	}
456	}
457
458	/// Add the qualifiers from the given set to this set, given that
459	/// they don't conflict.
460	void addConsistentQualifiers(Qualifiers qs) {
461	assert(getAddressSpace() == qs.getAddressSpace() \|\|((getAddressSpace() == qs.getAddressSpace() \|\| !hasAddressSpace () \|\| !qs.hasAddressSpace()) ? static_cast<void> (0) : __assert_fail ("getAddressSpace() == qs.getAddressSpace() \|\| !hasAddressSpace() \|\| !qs.hasAddressSpace()" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 462, __PRETTY_FUNCTION__))
462	!hasAddressSpace() \|\| !qs.hasAddressSpace())((getAddressSpace() == qs.getAddressSpace() \|\| !hasAddressSpace () \|\| !qs.hasAddressSpace()) ? static_cast<void> (0) : __assert_fail ("getAddressSpace() == qs.getAddressSpace() \|\| !hasAddressSpace() \|\| !qs.hasAddressSpace()" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 462, __PRETTY_FUNCTION__));
463	assert(getObjCGCAttr() == qs.getObjCGCAttr() \|\|((getObjCGCAttr() == qs.getObjCGCAttr() \|\| !hasObjCGCAttr() \|\| !qs.hasObjCGCAttr()) ? static_cast<void> (0) : __assert_fail ("getObjCGCAttr() == qs.getObjCGCAttr() \|\| !hasObjCGCAttr() \|\| !qs.hasObjCGCAttr()" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 464, __PRETTY_FUNCTION__))
464	!hasObjCGCAttr() \|\| !qs.hasObjCGCAttr())((getObjCGCAttr() == qs.getObjCGCAttr() \|\| !hasObjCGCAttr() \|\| !qs.hasObjCGCAttr()) ? static_cast<void> (0) : __assert_fail ("getObjCGCAttr() == qs.getObjCGCAttr() \|\| !hasObjCGCAttr() \|\| !qs.hasObjCGCAttr()" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 464, __PRETTY_FUNCTION__));
465	assert(getObjCLifetime() == qs.getObjCLifetime() \|\|((getObjCLifetime() == qs.getObjCLifetime() \|\| !hasObjCLifetime () \|\| !qs.hasObjCLifetime()) ? static_cast<void> (0) : __assert_fail ("getObjCLifetime() == qs.getObjCLifetime() \|\| !hasObjCLifetime() \|\| !qs.hasObjCLifetime()" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 466, __PRETTY_FUNCTION__))
466	!hasObjCLifetime() \|\| !qs.hasObjCLifetime())((getObjCLifetime() == qs.getObjCLifetime() \|\| !hasObjCLifetime () \|\| !qs.hasObjCLifetime()) ? static_cast<void> (0) : __assert_fail ("getObjCLifetime() == qs.getObjCLifetime() \|\| !hasObjCLifetime() \|\| !qs.hasObjCLifetime()" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 466, __PRETTY_FUNCTION__));
467	Mask \|= qs.Mask;
468	}
469
470	/// Returns true if address space A is equal to or a superset of B.
471	/// OpenCL v2.0 defines conversion rules (OpenCLC v2.0 s6.5.5) and notion of
472	/// overlapping address spaces.
473	/// CL1.1 or CL1.2:
474	/// every address space is a superset of itself.
475	/// CL2.0 adds:
476	/// __generic is a superset of any address space except for __constant.
477	static bool isAddressSpaceSupersetOf(LangAS A, LangAS B) {
478	// Address spaces must match exactly.
479	return A == B \|\|
480	// Otherwise in OpenCLC v2.0 s6.5.5: every address space except
481	// for __constant can be used as __generic.
482	(A == LangAS::opencl_generic && B != LangAS::opencl_constant) \|\|
483	// We also define global_device and global_host address spaces,
484	// to distinguish global pointers allocated on host from pointers
485	// allocated on device, which are a subset of __global.
486	(A == LangAS::opencl_global && (B == LangAS::opencl_global_device \|\|
487	B == LangAS::opencl_global_host)) \|\|
488	// Consider pointer size address spaces to be equivalent to default.
489	((isPtrSizeAddressSpace(A) \|\| A == LangAS::Default) &&
490	(isPtrSizeAddressSpace(B) \|\| B == LangAS::Default));
491	}
492
493	/// Returns true if the address space in these qualifiers is equal to or
494	/// a superset of the address space in the argument qualifiers.
495	bool isAddressSpaceSupersetOf(Qualifiers other) const {
496	return isAddressSpaceSupersetOf(getAddressSpace(), other.getAddressSpace());
497	}
498
499	/// Determines if these qualifiers compatibly include another set.
500	/// Generally this answers the question of whether an object with the other
501	/// qualifiers can be safely used as an object with these qualifiers.
502	bool compatiblyIncludes(Qualifiers other) const {
503	return isAddressSpaceSupersetOf(other) &&
504	// ObjC GC qualifiers can match, be added, or be removed, but can't
505	// be changed.
506	(getObjCGCAttr() == other.getObjCGCAttr() \|\| !hasObjCGCAttr() \|\|
507	!other.hasObjCGCAttr()) &&
508	// ObjC lifetime qualifiers must match exactly.
509	getObjCLifetime() == other.getObjCLifetime() &&
510	// CVR qualifiers may subset.
511	(((Mask & CVRMask) \| (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
512	// U qualifier may superset.
513	(!other.hasUnaligned() \|\| hasUnaligned());
514	}
515
516	/// Determines if these qualifiers compatibly include another set of
517	/// qualifiers from the narrow perspective of Objective-C ARC lifetime.
518	///
519	/// One set of Objective-C lifetime qualifiers compatibly includes the other
520	/// if the lifetime qualifiers match, or if both are non-__weak and the
521	/// including set also contains the 'const' qualifier, or both are non-__weak
522	/// and one is None (which can only happen in non-ARC modes).
523	bool compatiblyIncludesObjCLifetime(Qualifiers other) const {
524	if (getObjCLifetime() == other.getObjCLifetime())
525	return true;
526
527	if (getObjCLifetime() == OCL_Weak \|\| other.getObjCLifetime() == OCL_Weak)
528	return false;
529
530	if (getObjCLifetime() == OCL_None \|\| other.getObjCLifetime() == OCL_None)
531	return true;
532
533	return hasConst();
534	}
535
536	/// Determine whether this set of qualifiers is a strict superset of
537	/// another set of qualifiers, not considering qualifier compatibility.
538	bool isStrictSupersetOf(Qualifiers Other) const;
539
540	bool operator==(Qualifiers Other) const { return Mask == Other.Mask; }
541	bool operator!=(Qualifiers Other) const { return Mask != Other.Mask; }
542
543	explicit operator bool() const { return hasQualifiers(); }
544
545	Qualifiers &operator+=(Qualifiers R) {
546	addQualifiers(R);
547	return *this;
548	}
549
550	// Union two qualifier sets. If an enumerated qualifier appears
551	// in both sets, use the one from the right.
552	friend Qualifiers operator+(Qualifiers L, Qualifiers R) {
553	L += R;
554	return L;
555	}
556
557	Qualifiers &operator-=(Qualifiers R) {
558	removeQualifiers(R);
559	return *this;
560	}
561
562	/// Compute the difference between two qualifier sets.
563	friend Qualifiers operator-(Qualifiers L, Qualifiers R) {
564	L -= R;
565	return L;
566	}
567
568	std::string getAsString() const;
569	std::string getAsString(const PrintingPolicy &Policy) const;
570
571	static std::string getAddrSpaceAsString(LangAS AS);
572
573	bool isEmptyWhenPrinted(const PrintingPolicy &Policy) const;
574	void print(raw_ostream &OS, const PrintingPolicy &Policy,
575	bool appendSpaceIfNonEmpty = false) const;
576
577	void Profile(llvm::FoldingSetNodeID &ID) const {
578	ID.AddInteger(Mask);
579	}
580
581	private:
582	// bits: \|0 1 2\|3\|4 .. 5\|6 .. 8\|9 ... 31\|
583	// \|C R V\|U\|GCAttr\|Lifetime\|AddressSpace\|
584	uint32_t Mask = 0;
585
586	static const uint32_t UMask = 0x8;
587	static const uint32_t UShift = 3;
588	static const uint32_t GCAttrMask = 0x30;
589	static const uint32_t GCAttrShift = 4;
590	static const uint32_t LifetimeMask = 0x1C0;
591	static const uint32_t LifetimeShift = 6;
592	static const uint32_t AddressSpaceMask =
593	~(CVRMask \| UMask \| GCAttrMask \| LifetimeMask);
594	static const uint32_t AddressSpaceShift = 9;
595	};
596
597	/// A std::pair-like structure for storing a qualified type split
598	/// into its local qualifiers and its locally-unqualified type.
599	struct SplitQualType {
600	/// The locally-unqualified type.
601	const Type *Ty = nullptr;
602
603	/// The local qualifiers.
604	Qualifiers Quals;
605
606	SplitQualType() = default;
607	SplitQualType(const Type *ty, Qualifiers qs) : Ty(ty), Quals(qs) {}
608
609	SplitQualType getSingleStepDesugaredType() const; // end of this file
610
611	// Make std::tie work.
612	std::pair<const Type *,Qualifiers> asPair() const {
613	return std::pair<const Type *, Qualifiers>(Ty, Quals);
614	}
615
616	friend bool operator==(SplitQualType a, SplitQualType b) {
617	return a.Ty == b.Ty && a.Quals == b.Quals;
618	}
619	friend bool operator!=(SplitQualType a, SplitQualType b) {
620	return a.Ty != b.Ty \|\| a.Quals != b.Quals;
621	}
622	};
623
624	/// The kind of type we are substituting Objective-C type arguments into.
625	///
626	/// The kind of substitution affects the replacement of type parameters when
627	/// no concrete type information is provided, e.g., when dealing with an
628	/// unspecialized type.
629	enum class ObjCSubstitutionContext {
630	/// An ordinary type.
631	Ordinary,
632
633	/// The result type of a method or function.
634	Result,
635
636	/// The parameter type of a method or function.
637	Parameter,
638
639	/// The type of a property.
640	Property,
641
642	/// The superclass of a type.
643	Superclass,
644	};
645
646	/// A (possibly-)qualified type.
647	///
648	/// For efficiency, we don't store CV-qualified types as nodes on their
649	/// own: instead each reference to a type stores the qualifiers. This
650	/// greatly reduces the number of nodes we need to allocate for types (for
651	/// example we only need one for 'int', 'const int', 'volatile int',
652	/// 'const volatile int', etc).
653	///
654	/// As an added efficiency bonus, instead of making this a pair, we
655	/// just store the two bits we care about in the low bits of the
656	/// pointer. To handle the packing/unpacking, we make QualType be a
657	/// simple wrapper class that acts like a smart pointer. A third bit
658	/// indicates whether there are extended qualifiers present, in which
659	/// case the pointer points to a special structure.
660	class QualType {
661	friend class QualifierCollector;
662
663	// Thankfully, these are efficiently composable.
664	llvm::PointerIntPair<llvm::PointerUnion<const Type , const ExtQuals >,
665	Qualifiers::FastWidth> Value;
666
667	const ExtQuals *getExtQualsUnsafe() const {
668	return Value.getPointer().get<const ExtQuals*>();
669	}
670
671	const Type *getTypePtrUnsafe() const {
672	return Value.getPointer().get<const Type*>();
673	}
674
675	const ExtQualsTypeCommonBase *getCommonPtr() const {
676	assert(!isNull() && "Cannot retrieve a NULL type pointer")((!isNull() && "Cannot retrieve a NULL type pointer") ? static_cast<void> (0) : __assert_fail ("!isNull() && \"Cannot retrieve a NULL type pointer\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 676, __PRETTY_FUNCTION__));
677	auto CommonPtrVal = reinterpret_cast<uintptr_t>(Value.getOpaqueValue());
678	CommonPtrVal &= ~(uintptr_t)((1 << TypeAlignmentInBits) - 1);
679	return reinterpret_cast<ExtQualsTypeCommonBase*>(CommonPtrVal);
680	}
681
682	public:
683	QualType() = default;
684	QualType(const Type *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
685	QualType(const ExtQuals *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
686
687	unsigned getLocalFastQualifiers() const { return Value.getInt(); }
688	void setLocalFastQualifiers(unsigned Quals) { Value.setInt(Quals); }
689
690	/// Retrieves a pointer to the underlying (unqualified) type.
691	///
692	/// This function requires that the type not be NULL. If the type might be
693	/// NULL, use the (slightly less efficient) \c getTypePtrOrNull().
694	const Type *getTypePtr() const;
695
696	const Type *getTypePtrOrNull() const;
697
698	/// Retrieves a pointer to the name of the base type.
699	const IdentifierInfo *getBaseTypeIdentifier() const;
700
701	/// Divides a QualType into its unqualified type and a set of local
702	/// qualifiers.
703	SplitQualType split() const;
704
705	void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }
706
707	static QualType getFromOpaquePtr(const void *Ptr) {
708	QualType T;
709	T.Value.setFromOpaqueValue(const_cast<void*>(Ptr));
710	return T;
711	}
712
713	const Type &operator*() const {
714	return *getTypePtr();
715	}
716
717	const Type *operator->() const {
718	return getTypePtr();
719	}
720
721	bool isCanonical() const;
722	bool isCanonicalAsParam() const;
723
724	/// Return true if this QualType doesn't point to a type yet.
725	bool isNull() const {
726	return Value.getPointer().isNull();
727	}
728
729	/// Determine whether this particular QualType instance has the
730	/// "const" qualifier set, without looking through typedefs that may have
731	/// added "const" at a different level.
732	bool isLocalConstQualified() const {
733	return (getLocalFastQualifiers() & Qualifiers::Const);
734	}
735
736	/// Determine whether this type is const-qualified.
737	bool isConstQualified() const;
738
739	/// Determine whether this particular QualType instance has the
740	/// "restrict" qualifier set, without looking through typedefs that may have
741	/// added "restrict" at a different level.
742	bool isLocalRestrictQualified() const {
743	return (getLocalFastQualifiers() & Qualifiers::Restrict);
744	}
745
746	/// Determine whether this type is restrict-qualified.
747	bool isRestrictQualified() const;
748
749	/// Determine whether this particular QualType instance has the
750	/// "volatile" qualifier set, without looking through typedefs that may have
751	/// added "volatile" at a different level.
752	bool isLocalVolatileQualified() const {
753	return (getLocalFastQualifiers() & Qualifiers::Volatile);
754	}
755
756	/// Determine whether this type is volatile-qualified.
757	bool isVolatileQualified() const;
758
759	/// Determine whether this particular QualType instance has any
760	/// qualifiers, without looking through any typedefs that might add
761	/// qualifiers at a different level.
762	bool hasLocalQualifiers() const {
763	return getLocalFastQualifiers() \|\| hasLocalNonFastQualifiers();
764	}
765
766	/// Determine whether this type has any qualifiers.
767	bool hasQualifiers() const;
768
769	/// Determine whether this particular QualType instance has any
770	/// "non-fast" qualifiers, e.g., those that are stored in an ExtQualType
771	/// instance.
772	bool hasLocalNonFastQualifiers() const {
773	return Value.getPointer().is<const ExtQuals*>();
774	}
775
776	/// Retrieve the set of qualifiers local to this particular QualType
777	/// instance, not including any qualifiers acquired through typedefs or
778	/// other sugar.
779	Qualifiers getLocalQualifiers() const;
780
781	/// Retrieve the set of qualifiers applied to this type.
782	Qualifiers getQualifiers() const;
783
784	/// Retrieve the set of CVR (const-volatile-restrict) qualifiers
785	/// local to this particular QualType instance, not including any qualifiers
786	/// acquired through typedefs or other sugar.
787	unsigned getLocalCVRQualifiers() const {
788	return getLocalFastQualifiers();
789	}
790
791	/// Retrieve the set of CVR (const-volatile-restrict) qualifiers
792	/// applied to this type.
793	unsigned getCVRQualifiers() const;
794
795	bool isConstant(const ASTContext& Ctx) const {
796	return QualType::isConstant(*this, Ctx);
797	}
798
799	/// Determine whether this is a Plain Old Data (POD) type (C++ 3.9p10).
800	bool isPODType(const ASTContext &Context) const;
801
802	/// Return true if this is a POD type according to the rules of the C++98
803	/// standard, regardless of the current compilation's language.
804	bool isCXX98PODType(const ASTContext &Context) const;
805
806	/// Return true if this is a POD type according to the more relaxed rules
807	/// of the C++11 standard, regardless of the current compilation's language.
808	/// (C++0x [basic.types]p9). Note that, unlike
809	/// CXXRecordDecl::isCXX11StandardLayout, this takes DRs into account.
810	bool isCXX11PODType(const ASTContext &Context) const;
811
812	/// Return true if this is a trivial type per (C++0x [basic.types]p9)
813	bool isTrivialType(const ASTContext &Context) const;
814
815	/// Return true if this is a trivially copyable type (C++0x [basic.types]p9)
816	bool isTriviallyCopyableType(const ASTContext &Context) const;
817
818
819	/// Returns true if it is a class and it might be dynamic.
820	bool mayBeDynamicClass() const;
821
822	/// Returns true if it is not a class or if the class might not be dynamic.
823	bool mayBeNotDynamicClass() const;
824
825	// Don't promise in the API that anything besides 'const' can be
826	// easily added.
827
828	/// Add the `const` type qualifier to this QualType.
829	void addConst() {
830	addFastQualifiers(Qualifiers::Const);
831	}
832	QualType withConst() const {
833	return withFastQualifiers(Qualifiers::Const);
834	}
835
836	/// Add the `volatile` type qualifier to this QualType.
837	void addVolatile() {
838	addFastQualifiers(Qualifiers::Volatile);
839	}
840	QualType withVolatile() const {
841	return withFastQualifiers(Qualifiers::Volatile);
842	}
843
844	/// Add the `restrict` qualifier to this QualType.
845	void addRestrict() {
846	addFastQualifiers(Qualifiers::Restrict);
847	}
848	QualType withRestrict() const {
849	return withFastQualifiers(Qualifiers::Restrict);
850	}
851
852	QualType withCVRQualifiers(unsigned CVR) const {
853	return withFastQualifiers(CVR);
854	}
855
856	void addFastQualifiers(unsigned TQs) {
857	assert(!(TQs & ~Qualifiers::FastMask)((!(TQs & ~Qualifiers::FastMask) && "non-fast qualifier bits set in mask!" ) ? static_cast<void> (0) : __assert_fail ("!(TQs & ~Qualifiers::FastMask) && \"non-fast qualifier bits set in mask!\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 858, __PRETTY_FUNCTION__))
858	&& "non-fast qualifier bits set in mask!")((!(TQs & ~Qualifiers::FastMask) && "non-fast qualifier bits set in mask!" ) ? static_cast<void> (0) : __assert_fail ("!(TQs & ~Qualifiers::FastMask) && \"non-fast qualifier bits set in mask!\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 858, __PRETTY_FUNCTION__));
859	Value.setInt(Value.getInt() \| TQs);
860	}
861
862	void removeLocalConst();
863	void removeLocalVolatile();
864	void removeLocalRestrict();
865	void removeLocalCVRQualifiers(unsigned Mask);
866
867	void removeLocalFastQualifiers() { Value.setInt(0); }
868	void removeLocalFastQualifiers(unsigned Mask) {
869	assert(!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers")((!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers" ) ? static_cast<void> (0) : __assert_fail ("!(Mask & ~Qualifiers::FastMask) && \"mask has non-fast qualifiers\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 869, __PRETTY_FUNCTION__));
870	Value.setInt(Value.getInt() & ~Mask);
871	}
872
873	// Creates a type with the given qualifiers in addition to any
874	// qualifiers already on this type.
875	QualType withFastQualifiers(unsigned TQs) const {
876	QualType T = *this;
877	T.addFastQualifiers(TQs);
878	return T;
879	}
880
881	// Creates a type with exactly the given fast qualifiers, removing
882	// any existing fast qualifiers.
883	QualType withExactLocalFastQualifiers(unsigned TQs) const {
884	return withoutLocalFastQualifiers().withFastQualifiers(TQs);
885	}
886
887	// Removes fast qualifiers, but leaves any extended qualifiers in place.
888	QualType withoutLocalFastQualifiers() const {
889	QualType T = *this;
890	T.removeLocalFastQualifiers();
891	return T;
892	}
893
894	QualType getCanonicalType() const;
895
896	/// Return this type with all of the instance-specific qualifiers
897	/// removed, but without removing any qualifiers that may have been applied
898	/// through typedefs.
899	QualType getLocalUnqualifiedType() const { return QualType(getTypePtr(), 0); }
900
901	/// Retrieve the unqualified variant of the given type,
902	/// removing as little sugar as possible.
903	///
904	/// This routine looks through various kinds of sugar to find the
905	/// least-desugared type that is unqualified. For example, given:
906	///
907	/// \code
908	/// typedef int Integer;
909	/// typedef const Integer CInteger;
910	/// typedef CInteger DifferenceType;
911	/// \endcode
912	///
913	/// Executing \c getUnqualifiedType() on the type \c DifferenceType will
914	/// desugar until we hit the type \c Integer, which has no qualifiers on it.
915	///
916	/// The resulting type might still be qualified if it's sugar for an array
917	/// type. To strip qualifiers even from within a sugared array type, use
918	/// ASTContext::getUnqualifiedArrayType.
919	inline QualType getUnqualifiedType() const;
920
921	/// Retrieve the unqualified variant of the given type, removing as little
922	/// sugar as possible.
923	///
924	/// Like getUnqualifiedType(), but also returns the set of
925	/// qualifiers that were built up.
926	///
927	/// The resulting type might still be qualified if it's sugar for an array
928	/// type. To strip qualifiers even from within a sugared array type, use
929	/// ASTContext::getUnqualifiedArrayType.
930	inline SplitQualType getSplitUnqualifiedType() const;
931
932	/// Determine whether this type is more qualified than the other
933	/// given type, requiring exact equality for non-CVR qualifiers.
934	bool isMoreQualifiedThan(QualType Other) const;
935
936	/// Determine whether this type is at least as qualified as the other
937	/// given type, requiring exact equality for non-CVR qualifiers.
938	bool isAtLeastAsQualifiedAs(QualType Other) const;
939
940	QualType getNonReferenceType() const;
941
942	/// Determine the type of a (typically non-lvalue) expression with the
943	/// specified result type.
944	///
945	/// This routine should be used for expressions for which the return type is
946	/// explicitly specified (e.g., in a cast or call) and isn't necessarily
947	/// an lvalue. It removes a top-level reference (since there are no
948	/// expressions of reference type) and deletes top-level cvr-qualifiers
949	/// from non-class types (in C++) or all types (in C).
950	QualType getNonLValueExprType(const ASTContext &Context) const;
951
952	/// Remove an outer pack expansion type (if any) from this type. Used as part
953	/// of converting the type of a declaration to the type of an expression that
954	/// references that expression. It's meaningless for an expression to have a
955	/// pack expansion type.
956	QualType getNonPackExpansionType() const;
957
958	/// Return the specified type with any "sugar" removed from
959	/// the type. This takes off typedefs, typeof's etc. If the outer level of
960	/// the type is already concrete, it returns it unmodified. This is similar
961	/// to getting the canonical type, but it doesn't remove all typedefs. For
962	/// example, it returns "T" as "T", (not as "int*"), because the pointer is
963	/// concrete.
964	///
965	/// Qualifiers are left in place.
966	QualType getDesugaredType(const ASTContext &Context) const {
967	return getDesugaredType(*this, Context);
968	}
969
970	SplitQualType getSplitDesugaredType() const {
971	return getSplitDesugaredType(*this);
972	}
973
974	/// Return the specified type with one level of "sugar" removed from
975	/// the type.
976	///
977	/// This routine takes off the first typedef, typeof, etc. If the outer level
978	/// of the type is already concrete, it returns it unmodified.
979	QualType getSingleStepDesugaredType(const ASTContext &Context) const {
980	return getSingleStepDesugaredTypeImpl(*this, Context);
981	}
982
983	/// Returns the specified type after dropping any
984	/// outer-level parentheses.
985	QualType IgnoreParens() const {
986	if (isa<ParenType>(*this))
987	return QualType::IgnoreParens(*this);
988	return *this;
989	}
990
991	/// Indicate whether the specified types and qualifiers are identical.
992	friend bool operator==(const QualType &LHS, const QualType &RHS) {
993	return LHS.Value == RHS.Value;
994	}
995	friend bool operator!=(const QualType &LHS, const QualType &RHS) {
996	return LHS.Value != RHS.Value;
997	}
998	friend bool operator<(const QualType &LHS, const QualType &RHS) {
999	return LHS.Value < RHS.Value;
1000	}
1001
1002	static std::string getAsString(SplitQualType split,
1003	const PrintingPolicy &Policy) {
1004	return getAsString(split.Ty, split.Quals, Policy);
1005	}
1006	static std::string getAsString(const Type *ty, Qualifiers qs,
1007	const PrintingPolicy &Policy);
1008
1009	std::string getAsString() const;
1010	std::string getAsString(const PrintingPolicy &Policy) const;
1011
1012	void print(raw_ostream &OS, const PrintingPolicy &Policy,
1013	const Twine &PlaceHolder = Twine(),
1014	unsigned Indentation = 0) const;
1015
1016	static void print(SplitQualType split, raw_ostream &OS,
1017	const PrintingPolicy &policy, const Twine &PlaceHolder,
1018	unsigned Indentation = 0) {
1019	return print(split.Ty, split.Quals, OS, policy, PlaceHolder, Indentation);
1020	}
1021
1022	static void print(const Type *ty, Qualifiers qs,
1023	raw_ostream &OS, const PrintingPolicy &policy,
1024	const Twine &PlaceHolder,
1025	unsigned Indentation = 0);
1026
1027	void getAsStringInternal(std::string &Str,
1028	const PrintingPolicy &Policy) const;
1029
1030	static void getAsStringInternal(SplitQualType split, std::string &out,
1031	const PrintingPolicy &policy) {
1032	return getAsStringInternal(split.Ty, split.Quals, out, policy);
1033	}
1034
1035	static void getAsStringInternal(const Type *ty, Qualifiers qs,
1036	std::string &out,
1037	const PrintingPolicy &policy);
1038
1039	class StreamedQualTypeHelper {
1040	const QualType &T;
1041	const PrintingPolicy &Policy;
1042	const Twine &PlaceHolder;
1043	unsigned Indentation;
1044
1045	public:
1046	StreamedQualTypeHelper(const QualType &T, const PrintingPolicy &Policy,
1047	const Twine &PlaceHolder, unsigned Indentation)
1048	: T(T), Policy(Policy), PlaceHolder(PlaceHolder),
1049	Indentation(Indentation) {}
1050
1051	friend raw_ostream &operator<<(raw_ostream &OS,
1052	const StreamedQualTypeHelper &SQT) {
1053	SQT.T.print(OS, SQT.Policy, SQT.PlaceHolder, SQT.Indentation);
1054	return OS;
1055	}
1056	};
1057
1058	StreamedQualTypeHelper stream(const PrintingPolicy &Policy,
1059	const Twine &PlaceHolder = Twine(),
1060	unsigned Indentation = 0) const {
1061	return StreamedQualTypeHelper(*this, Policy, PlaceHolder, Indentation);
1062	}
1063
1064	void dump(const char *s) const;
1065	void dump() const;
1066	void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
1067
1068	void Profile(llvm::FoldingSetNodeID &ID) const {
1069	ID.AddPointer(getAsOpaquePtr());
1070	}
1071
1072	/// Check if this type has any address space qualifier.
1073	inline bool hasAddressSpace() const;
1074
1075	/// Return the address space of this type.
1076	inline LangAS getAddressSpace() const;
1077
1078	/// Returns true if address space qualifiers overlap with T address space
1079	/// qualifiers.
1080	/// OpenCL C defines conversion rules for pointers to different address spaces
1081	/// and notion of overlapping address spaces.
1082	/// CL1.1 or CL1.2:
1083	/// address spaces overlap iff they are they same.
1084	/// OpenCL C v2.0 s6.5.5 adds:
1085	/// __generic overlaps with any address space except for __constant.
1086	bool isAddressSpaceOverlapping(QualType T) const {
1087	Qualifiers Q = getQualifiers();
1088	Qualifiers TQ = T.getQualifiers();
1089	// Address spaces overlap if at least one of them is a superset of another
1090	return Q.isAddressSpaceSupersetOf(TQ) \|\| TQ.isAddressSpaceSupersetOf(Q);
1091	}
1092
1093	/// Returns gc attribute of this type.
1094	inline Qualifiers::GC getObjCGCAttr() const;
1095
1096	/// true when Type is objc's weak.
1097	bool isObjCGCWeak() const {
1098	return getObjCGCAttr() == Qualifiers::Weak;
1099	}
1100
1101	/// true when Type is objc's strong.
1102	bool isObjCGCStrong() const {
1103	return getObjCGCAttr() == Qualifiers::Strong;
1104	}
1105
1106	/// Returns lifetime attribute of this type.
1107	Qualifiers::ObjCLifetime getObjCLifetime() const {
1108	return getQualifiers().getObjCLifetime();
1109	}
1110
1111	bool hasNonTrivialObjCLifetime() const {
1112	return getQualifiers().hasNonTrivialObjCLifetime();
1113	}
1114
1115	bool hasStrongOrWeakObjCLifetime() const {
1116	return getQualifiers().hasStrongOrWeakObjCLifetime();
1117	}
1118
1119	// true when Type is objc's weak and weak is enabled but ARC isn't.
1120	bool isNonWeakInMRRWithObjCWeak(const ASTContext &Context) const;
1121
1122	enum PrimitiveDefaultInitializeKind {
1123	/// The type does not fall into any of the following categories. Note that
1124	/// this case is zero-valued so that values of this enum can be used as a
1125	/// boolean condition for non-triviality.
1126	PDIK_Trivial,
1127
1128	/// The type is an Objective-C retainable pointer type that is qualified
1129	/// with the ARC __strong qualifier.
1130	PDIK_ARCStrong,
1131
1132	/// The type is an Objective-C retainable pointer type that is qualified
1133	/// with the ARC __weak qualifier.
1134	PDIK_ARCWeak,
1135
1136	/// The type is a struct containing a field whose type is not PCK_Trivial.
1137	PDIK_Struct
1138	};
1139
1140	/// Functions to query basic properties of non-trivial C struct types.
1141
1142	/// Check if this is a non-trivial type that would cause a C struct
1143	/// transitively containing this type to be non-trivial to default initialize
1144	/// and return the kind.
1145	PrimitiveDefaultInitializeKind
1146	isNonTrivialToPrimitiveDefaultInitialize() const;
1147
1148	enum PrimitiveCopyKind {
1149	/// The type does not fall into any of the following categories. Note that
1150	/// this case is zero-valued so that values of this enum can be used as a
1151	/// boolean condition for non-triviality.
1152	PCK_Trivial,
1153
1154	/// The type would be trivial except that it is volatile-qualified. Types
1155	/// that fall into one of the other non-trivial cases may additionally be
1156	/// volatile-qualified.
1157	PCK_VolatileTrivial,
1158
1159	/// The type is an Objective-C retainable pointer type that is qualified
1160	/// with the ARC __strong qualifier.
1161	PCK_ARCStrong,
1162
1163	/// The type is an Objective-C retainable pointer type that is qualified
1164	/// with the ARC __weak qualifier.
1165	PCK_ARCWeak,
1166
1167	/// The type is a struct containing a field whose type is neither
1168	/// PCK_Trivial nor PCK_VolatileTrivial.
1169	/// Note that a C++ struct type does not necessarily match this; C++ copying
1170	/// semantics are too complex to express here, in part because they depend
1171	/// on the exact constructor or assignment operator that is chosen by
1172	/// overload resolution to do the copy.
1173	PCK_Struct
1174	};
1175
1176	/// Check if this is a non-trivial type that would cause a C struct
1177	/// transitively containing this type to be non-trivial to copy and return the
1178	/// kind.
1179	PrimitiveCopyKind isNonTrivialToPrimitiveCopy() const;
1180
1181	/// Check if this is a non-trivial type that would cause a C struct
1182	/// transitively containing this type to be non-trivial to destructively
1183	/// move and return the kind. Destructive move in this context is a C++-style
1184	/// move in which the source object is placed in a valid but unspecified state
1185	/// after it is moved, as opposed to a truly destructive move in which the
1186	/// source object is placed in an uninitialized state.
1187	PrimitiveCopyKind isNonTrivialToPrimitiveDestructiveMove() const;
1188
1189	enum DestructionKind {
1190	DK_none,
1191	DK_cxx_destructor,
1192	DK_objc_strong_lifetime,
1193	DK_objc_weak_lifetime,
1194	DK_nontrivial_c_struct
1195	};
1196
1197	/// Returns a nonzero value if objects of this type require
1198	/// non-trivial work to clean up after. Non-zero because it's
1199	/// conceivable that qualifiers (objc_gc(weak)?) could make
1200	/// something require destruction.
1201	DestructionKind isDestructedType() const {
1202	return isDestructedTypeImpl(*this);
1203	}
1204
1205	/// Check if this is or contains a C union that is non-trivial to
1206	/// default-initialize, which is a union that has a member that is non-trivial
1207	/// to default-initialize. If this returns true,
1208	/// isNonTrivialToPrimitiveDefaultInitialize returns PDIK_Struct.
1209	bool hasNonTrivialToPrimitiveDefaultInitializeCUnion() const;
1210
1211	/// Check if this is or contains a C union that is non-trivial to destruct,
1212	/// which is a union that has a member that is non-trivial to destruct. If
1213	/// this returns true, isDestructedType returns DK_nontrivial_c_struct.
1214	bool hasNonTrivialToPrimitiveDestructCUnion() const;
1215
1216	/// Check if this is or contains a C union that is non-trivial to copy, which
1217	/// is a union that has a member that is non-trivial to copy. If this returns
1218	/// true, isNonTrivialToPrimitiveCopy returns PCK_Struct.
1219	bool hasNonTrivialToPrimitiveCopyCUnion() const;
1220
1221	/// Determine whether expressions of the given type are forbidden
1222	/// from being lvalues in C.
1223	///
1224	/// The expression types that are forbidden to be lvalues are:
1225	/// - 'void', but not qualified void
1226	/// - function types
1227	///
1228	/// The exact rule here is C99 6.3.2.1:
1229	/// An lvalue is an expression with an object type or an incomplete
1230	/// type other than void.
1231	bool isCForbiddenLValueType() const;
1232
1233	/// Substitute type arguments for the Objective-C type parameters used in the
1234	/// subject type.
1235	///
1236	/// \param ctx ASTContext in which the type exists.
1237	///
1238	/// \param typeArgs The type arguments that will be substituted for the
1239	/// Objective-C type parameters in the subject type, which are generally
1240	/// computed via \c Type::getObjCSubstitutions. If empty, the type
1241	/// parameters will be replaced with their bounds or id/Class, as appropriate
1242	/// for the context.
1243	///
1244	/// \param context The context in which the subject type was written.
1245	///
1246	/// \returns the resulting type.
1247	QualType substObjCTypeArgs(ASTContext &ctx,
1248	ArrayRef<QualType> typeArgs,
1249	ObjCSubstitutionContext context) const;
1250
1251	/// Substitute type arguments from an object type for the Objective-C type
1252	/// parameters used in the subject type.
1253	///
1254	/// This operation combines the computation of type arguments for
1255	/// substitution (\c Type::getObjCSubstitutions) with the actual process of
1256	/// substitution (\c QualType::substObjCTypeArgs) for the convenience of
1257	/// callers that need to perform a single substitution in isolation.
1258	///
1259	/// \param objectType The type of the object whose member type we're
1260	/// substituting into. For example, this might be the receiver of a message
1261	/// or the base of a property access.
1262	///
1263	/// \param dc The declaration context from which the subject type was
1264	/// retrieved, which indicates (for example) which type parameters should
1265	/// be substituted.
1266	///
1267	/// \param context The context in which the subject type was written.
1268	///
1269	/// \returns the subject type after replacing all of the Objective-C type
1270	/// parameters with their corresponding arguments.
1271	QualType substObjCMemberType(QualType objectType,
1272	const DeclContext *dc,
1273	ObjCSubstitutionContext context) const;
1274
1275	/// Strip Objective-C "__kindof" types from the given type.
1276	QualType stripObjCKindOfType(const ASTContext &ctx) const;
1277
1278	/// Remove all qualifiers including _Atomic.
1279	QualType getAtomicUnqualifiedType() const;
1280
1281	private:
1282	// These methods are implemented in a separate translation unit;
1283	// "static"-ize them to avoid creating temporary QualTypes in the
1284	// caller.
1285	static bool isConstant(QualType T, const ASTContext& Ctx);
1286	static QualType getDesugaredType(QualType T, const ASTContext &Context);
1287	static SplitQualType getSplitDesugaredType(QualType T);
1288	static SplitQualType getSplitUnqualifiedTypeImpl(QualType type);
1289	static QualType getSingleStepDesugaredTypeImpl(QualType type,
1290	const ASTContext &C);
1291	static QualType IgnoreParens(QualType T);
1292	static DestructionKind isDestructedTypeImpl(QualType type);
1293
1294	/// Check if \param RD is or contains a non-trivial C union.
1295	static bool hasNonTrivialToPrimitiveDefaultInitializeCUnion(const RecordDecl *RD);
1296	static bool hasNonTrivialToPrimitiveDestructCUnion(const RecordDecl *RD);
1297	static bool hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD);
1298	};
1299
1300	} // namespace clang
1301
1302	namespace llvm {
1303
1304	/// Implement simplify_type for QualType, so that we can dyn_cast from QualType
1305	/// to a specific Type class.
1306	template<> struct simplify_type< ::clang::QualType> {
1307	using SimpleType = const ::clang::Type *;
1308
1309	static SimpleType getSimplifiedValue(::clang::QualType Val) {
1310	return Val.getTypePtr();
1311	}
1312	};
1313
1314	// Teach SmallPtrSet that QualType is "basically a pointer".
1315	template<>
1316	struct PointerLikeTypeTraits<clang::QualType> {
1317	static inline void *getAsVoidPointer(clang::QualType P) {
1318	return P.getAsOpaquePtr();
1319	}
1320
1321	static inline clang::QualType getFromVoidPointer(void *P) {
1322	return clang::QualType::getFromOpaquePtr(P);
1323	}
1324
1325	// Various qualifiers go in low bits.
1326	static constexpr int NumLowBitsAvailable = 0;
1327	};
1328
1329	} // namespace llvm
1330
1331	namespace clang {
1332
1333	/// Base class that is common to both the \c ExtQuals and \c Type
1334	/// classes, which allows \c QualType to access the common fields between the
1335	/// two.
1336	class ExtQualsTypeCommonBase {
1337	friend class ExtQuals;
1338	friend class QualType;
1339	friend class Type;
1340
1341	/// The "base" type of an extended qualifiers type (\c ExtQuals) or
1342	/// a self-referential pointer (for \c Type).
1343	///
1344	/// This pointer allows an efficient mapping from a QualType to its
1345	/// underlying type pointer.
1346	const Type *const BaseType;
1347
1348	/// The canonical type of this type. A QualType.
1349	QualType CanonicalType;
1350
1351	ExtQualsTypeCommonBase(const Type *baseType, QualType canon)
1352	: BaseType(baseType), CanonicalType(canon) {}
1353	};
1354
1355	/// We can encode up to four bits in the low bits of a
1356	/// type pointer, but there are many more type qualifiers that we want
1357	/// to be able to apply to an arbitrary type. Therefore we have this
1358	/// struct, intended to be heap-allocated and used by QualType to
1359	/// store qualifiers.
1360	///
1361	/// The current design tags the 'const', 'restrict', and 'volatile' qualifiers
1362	/// in three low bits on the QualType pointer; a fourth bit records whether
1363	/// the pointer is an ExtQuals node. The extended qualifiers (address spaces,
1364	/// Objective-C GC attributes) are much more rare.
1365	class ExtQuals : public ExtQualsTypeCommonBase, public llvm::FoldingSetNode {
1366	// NOTE: changing the fast qualifiers should be straightforward as
1367	// long as you don't make 'const' non-fast.
1368	// 1. Qualifiers:
1369	// a) Modify the bitmasks (Qualifiers::TQ and DeclSpec::TQ).
1370	// Fast qualifiers must occupy the low-order bits.
1371	// b) Update Qualifiers::FastWidth and FastMask.
1372	// 2. QualType:
1373	// a) Update is{Volatile,Restrict}Qualified(), defined inline.
1374	// b) Update remove{Volatile,Restrict}, defined near the end of
1375	// this header.
1376	// 3. ASTContext:
1377	// a) Update get{Volatile,Restrict}Type.
1378
1379	/// The immutable set of qualifiers applied by this node. Always contains
1380	/// extended qualifiers.
1381	Qualifiers Quals;
1382
1383	ExtQuals *this_() { return this; }
1384
1385	public:
1386	ExtQuals(const Type *baseType, QualType canon, Qualifiers quals)
1387	: ExtQualsTypeCommonBase(baseType,
1388	canon.isNull() ? QualType(this_(), 0) : canon),
1389	Quals(quals) {
1390	assert(Quals.hasNonFastQualifiers()((Quals.hasNonFastQualifiers() && "ExtQuals created with no fast qualifiers" ) ? static_cast<void> (0) : __assert_fail ("Quals.hasNonFastQualifiers() && \"ExtQuals created with no fast qualifiers\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 1391, __PRETTY_FUNCTION__))
1391	&& "ExtQuals created with no fast qualifiers")((Quals.hasNonFastQualifiers() && "ExtQuals created with no fast qualifiers" ) ? static_cast<void> (0) : __assert_fail ("Quals.hasNonFastQualifiers() && \"ExtQuals created with no fast qualifiers\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 1391, __PRETTY_FUNCTION__));
1392	assert(!Quals.hasFastQualifiers()((!Quals.hasFastQualifiers() && "ExtQuals created with fast qualifiers" ) ? static_cast<void> (0) : __assert_fail ("!Quals.hasFastQualifiers() && \"ExtQuals created with fast qualifiers\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 1393, __PRETTY_FUNCTION__))
1393	&& "ExtQuals created with fast qualifiers")((!Quals.hasFastQualifiers() && "ExtQuals created with fast qualifiers" ) ? static_cast<void> (0) : __assert_fail ("!Quals.hasFastQualifiers() && \"ExtQuals created with fast qualifiers\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 1393, __PRETTY_FUNCTION__));
1394	}
1395
1396	Qualifiers getQualifiers() const { return Quals; }
1397
1398	bool hasObjCGCAttr() const { return Quals.hasObjCGCAttr(); }
1399	Qualifiers::GC getObjCGCAttr() const { return Quals.getObjCGCAttr(); }
1400
1401	bool hasObjCLifetime() const { return Quals.hasObjCLifetime(); }
1402	Qualifiers::ObjCLifetime getObjCLifetime() const {
1403	return Quals.getObjCLifetime();
1404	}
1405
1406	bool hasAddressSpace() const { return Quals.hasAddressSpace(); }
1407	LangAS getAddressSpace() const { return Quals.getAddressSpace(); }
1408
1409	const Type *getBaseType() const { return BaseType; }
1410
1411	public:
1412	void Profile(llvm::FoldingSetNodeID &ID) const {
1413	Profile(ID, getBaseType(), Quals);
1414	}
1415
1416	static void Profile(llvm::FoldingSetNodeID &ID,
1417	const Type *BaseType,
1418	Qualifiers Quals) {
1419	assert(!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!")((!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!" ) ? static_cast<void> (0) : __assert_fail ("!Quals.hasFastQualifiers() && \"fast qualifiers in ExtQuals hash!\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 1419, __PRETTY_FUNCTION__));
1420	ID.AddPointer(BaseType);
1421	Quals.Profile(ID);
1422	}
1423	};
1424
1425	/// The kind of C++11 ref-qualifier associated with a function type.
1426	/// This determines whether a member function's "this" object can be an
1427	/// lvalue, rvalue, or neither.
1428	enum RefQualifierKind {
1429	/// No ref-qualifier was provided.
1430	RQ_None = 0,
1431
1432	/// An lvalue ref-qualifier was provided (\c &).
1433	RQ_LValue,
1434
1435	/// An rvalue ref-qualifier was provided (\c &&).
1436	RQ_RValue
1437	};
1438
1439	/// Which keyword(s) were used to create an AutoType.
1440	enum class AutoTypeKeyword {
1441	/// auto
1442	Auto,
1443
1444	/// decltype(auto)
1445	DecltypeAuto,
1446
1447	/// __auto_type (GNU extension)
1448	GNUAutoType
1449	};
1450
1451	/// The base class of the type hierarchy.
1452	///
1453	/// A central concept with types is that each type always has a canonical
1454	/// type. A canonical type is the type with any typedef names stripped out
1455	/// of it or the types it references. For example, consider:
1456	///
1457	/// typedef int foo;
1458	/// typedef foo* bar;
1459	/// 'int ' 'foo ' 'bar'
1460	///
1461	/// There will be a Type object created for 'int'. Since int is canonical, its
1462	/// CanonicalType pointer points to itself. There is also a Type for 'foo' (a
1463	/// TypedefType). Its CanonicalType pointer points to the 'int' Type. Next
1464	/// there is a PointerType that represents 'int*', which, like 'int', is
1465	/// canonical. Finally, there is a PointerType type for 'foo*' whose canonical
1466	/// type is 'int*', and there is a TypedefType for 'bar', whose canonical type
1467	/// is also 'int*'.
1468	///
1469	/// Non-canonical types are useful for emitting diagnostics, without losing
1470	/// information about typedefs being used. Canonical types are useful for type
1471	/// comparisons (they allow by-pointer equality tests) and useful for reasoning
1472	/// about whether something has a particular form (e.g. is a function type),
1473	/// because they implicitly, recursively, strip all typedefs out of a type.
1474	///
1475	/// Types, once created, are immutable.
1476	///
1477	class alignas(8) Type : public ExtQualsTypeCommonBase {
1478	public:
1479	enum TypeClass {
1480	#define TYPE(Class, Base) Class,
1481	#define LAST_TYPE(Class) TypeLast = Class
1482	#define ABSTRACT_TYPE(Class, Base)
1483	#include "clang/AST/TypeNodes.inc"
1484	};
1485
1486	private:
1487	/// Bitfields required by the Type class.
1488	class TypeBitfields {
1489	friend class Type;
1490	template <class T> friend class TypePropertyCache;
1491
1492	/// TypeClass bitfield - Enum that specifies what subclass this belongs to.
1493	unsigned TC : 8;
1494
1495	/// Store information on the type dependency.
1496	unsigned Dependence : llvm::BitWidth<TypeDependence>;
1497
1498	/// True if the cache (i.e. the bitfields here starting with
1499	/// 'Cache') is valid.
1500	mutable unsigned CacheValid : 1;
1501
1502	/// Linkage of this type.
1503	mutable unsigned CachedLinkage : 3;
1504
1505	/// Whether this type involves and local or unnamed types.
1506	mutable unsigned CachedLocalOrUnnamed : 1;
1507
1508	/// Whether this type comes from an AST file.
1509	mutable unsigned FromAST : 1;
1510
1511	bool isCacheValid() const {
1512	return CacheValid;
1513	}
1514
1515	Linkage getLinkage() const {
1516	assert(isCacheValid() && "getting linkage from invalid cache")((isCacheValid() && "getting linkage from invalid cache" ) ? static_cast<void> (0) : __assert_fail ("isCacheValid() && \"getting linkage from invalid cache\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 1516, __PRETTY_FUNCTION__));
1517	return static_cast<Linkage>(CachedLinkage);
1518	}
1519
1520	bool hasLocalOrUnnamedType() const {
1521	assert(isCacheValid() && "getting linkage from invalid cache")((isCacheValid() && "getting linkage from invalid cache" ) ? static_cast<void> (0) : __assert_fail ("isCacheValid() && \"getting linkage from invalid cache\"" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 1521, __PRETTY_FUNCTION__));
1522	return CachedLocalOrUnnamed;
1523	}
1524	};
1525	enum { NumTypeBits = 8 + llvm::BitWidth<TypeDependence> + 6 };
1526
1527	protected:
1528	// These classes allow subclasses to somewhat cleanly pack bitfields
1529	// into Type.
1530
1531	class ArrayTypeBitfields {
1532	friend class ArrayType;
1533
1534	unsigned : NumTypeBits;
1535
1536	/// CVR qualifiers from declarations like
1537	/// 'int X[static restrict 4]'. For function parameters only.
1538	unsigned IndexTypeQuals : 3;
1539
1540	/// Storage class qualifiers from declarations like
1541	/// 'int X[static restrict 4]'. For function parameters only.
1542	/// Actually an ArrayType::ArraySizeModifier.
1543	unsigned SizeModifier : 3;
1544	};
1545
1546	class ConstantArrayTypeBitfields {
1547	friend class ConstantArrayType;
1548
1549	unsigned : NumTypeBits + 3 + 3;
1550
1551	/// Whether we have a stored size expression.
1552	unsigned HasStoredSizeExpr : 1;
1553	};
1554
1555	class BuiltinTypeBitfields {
1556	friend class BuiltinType;
1557
1558	unsigned : NumTypeBits;
1559
1560	/// The kind (BuiltinType::Kind) of builtin type this is.
1561	unsigned Kind : 8;
1562	};
1563
1564	/// FunctionTypeBitfields store various bits belonging to FunctionProtoType.
1565	/// Only common bits are stored here. Additional uncommon bits are stored
1566	/// in a trailing object after FunctionProtoType.
1567	class FunctionTypeBitfields {
1568	friend class FunctionProtoType;
1569	friend class FunctionType;
1570
1571	unsigned : NumTypeBits;
1572
1573	/// Extra information which affects how the function is called, like
1574	/// regparm and the calling convention.
1575	unsigned ExtInfo : 13;
1576
1577	/// The ref-qualifier associated with a \c FunctionProtoType.
1578	///
1579	/// This is a value of type \c RefQualifierKind.
1580	unsigned RefQualifier : 2;
1581
1582	/// Used only by FunctionProtoType, put here to pack with the
1583	/// other bitfields.
1584	/// The qualifiers are part of FunctionProtoType because...
1585	///
1586	/// C++ 8.3.5p4: The return type, the parameter type list and the
1587	/// cv-qualifier-seq, [...], are part of the function type.
1588	unsigned FastTypeQuals : Qualifiers::FastWidth;
1589	/// Whether this function has extended Qualifiers.
1590	unsigned HasExtQuals : 1;
1591
1592	/// The number of parameters this function has, not counting '...'.
1593	/// According to [implimits] 8 bits should be enough here but this is
1594	/// somewhat easy to exceed with metaprogramming and so we would like to
1595	/// keep NumParams as wide as reasonably possible.
1596	unsigned NumParams : 16;
1597
1598	/// The type of exception specification this function has.
1599	unsigned ExceptionSpecType : 4;
1600
1601	/// Whether this function has extended parameter information.
1602	unsigned HasExtParameterInfos : 1;
1603
1604	/// Whether the function is variadic.
1605	unsigned Variadic : 1;
1606
1607	/// Whether this function has a trailing return type.
1608	unsigned HasTrailingReturn : 1;
1609	};
1610
1611	class ObjCObjectTypeBitfields {
1612	friend class ObjCObjectType;
1613
1614	unsigned : NumTypeBits;
1615
1616	/// The number of type arguments stored directly on this object type.
1617	unsigned NumTypeArgs : 7;
1618
1619	/// The number of protocols stored directly on this object type.
1620	unsigned NumProtocols : 6;
1621
1622	/// Whether this is a "kindof" type.
1623	unsigned IsKindOf : 1;
1624	};
1625
1626	class ReferenceTypeBitfields {
1627	friend class ReferenceType;
1628
1629	unsigned : NumTypeBits;
1630
1631	/// True if the type was originally spelled with an lvalue sigil.
1632	/// This is never true of rvalue references but can also be false
1633	/// on lvalue references because of C++0x [dcl.typedef]p9,
1634	/// as follows:
1635	///
1636	/// typedef int &ref; // lvalue, spelled lvalue
1637	/// typedef int &&rvref; // rvalue
1638	/// ref &a; // lvalue, inner ref, spelled lvalue
1639	/// ref &&a; // lvalue, inner ref
1640	/// rvref &a; // lvalue, inner ref, spelled lvalue
1641	/// rvref &&a; // rvalue, inner ref
1642	unsigned SpelledAsLValue : 1;
1643
1644	/// True if the inner type is a reference type. This only happens
1645	/// in non-canonical forms.
1646	unsigned InnerRef : 1;
1647	};
1648
1649	class TypeWithKeywordBitfields {
1650	friend class TypeWithKeyword;
1651
1652	unsigned : NumTypeBits;
1653
1654	/// An ElaboratedTypeKeyword. 8 bits for efficient access.
1655	unsigned Keyword : 8;
1656	};
1657
1658	enum { NumTypeWithKeywordBits = 8 };
1659
1660	class ElaboratedTypeBitfields {
1661	friend class ElaboratedType;
1662
1663	unsigned : NumTypeBits;
1664	unsigned : NumTypeWithKeywordBits;
1665
1666	/// Whether the ElaboratedType has a trailing OwnedTagDecl.
1667	unsigned HasOwnedTagDecl : 1;
1668	};
1669
1670	class VectorTypeBitfields {
1671	friend class VectorType;
1672	friend class DependentVectorType;
1673
1674	unsigned : NumTypeBits;
1675
1676	/// The kind of vector, either a generic vector type or some
1677	/// target-specific vector type such as for AltiVec or Neon.
1678	unsigned VecKind : 3;
1679	/// The number of elements in the vector.
1680	uint32_t NumElements;
1681	};
1682
1683	class AttributedTypeBitfields {
1684	friend class AttributedType;
1685
1686	unsigned : NumTypeBits;
1687
1688	/// An AttributedType::Kind
1689	unsigned AttrKind : 32 - NumTypeBits;
1690	};
1691
1692	class AutoTypeBitfields {
1693	friend class AutoType;
1694
1695	unsigned : NumTypeBits;
1696
1697	/// Was this placeholder type spelled as 'auto', 'decltype(auto)',
1698	/// or '__auto_type'? AutoTypeKeyword value.
1699	unsigned Keyword : 2;
1700
1701	/// The number of template arguments in the type-constraints, which is
1702	/// expected to be able to hold at least 1024 according to [implimits].
1703	/// However as this limit is somewhat easy to hit with template
1704	/// metaprogramming we'd prefer to keep it as large as possible.
1705	/// At the moment it has been left as a non-bitfield since this type
1706	/// safely fits in 64 bits as an unsigned, so there is no reason to
1707	/// introduce the performance impact of a bitfield.
1708	unsigned NumArgs;
1709	};
1710
1711	class SubstTemplateTypeParmPackTypeBitfields {
1712	friend class SubstTemplateTypeParmPackType;
1713
1714	unsigned : NumTypeBits;
1715
1716	/// The number of template arguments in \c Arguments, which is
1717	/// expected to be able to hold at least 1024 according to [implimits].
1718	/// However as this limit is somewhat easy to hit with template
1719	/// metaprogramming we'd prefer to keep it as large as possible.
1720	/// At the moment it has been left as a non-bitfield since this type
1721	/// safely fits in 64 bits as an unsigned, so there is no reason to
1722	/// introduce the performance impact of a bitfield.
1723	unsigned NumArgs;
1724	};
1725
1726	class TemplateSpecializationTypeBitfields {
1727	friend class TemplateSpecializationType;
1728
1729	unsigned : NumTypeBits;
1730
1731	/// Whether this template specialization type is a substituted type alias.
1732	unsigned TypeAlias : 1;
1733
1734	/// The number of template arguments named in this class template
1735	/// specialization, which is expected to be able to hold at least 1024
1736	/// according to [implimits]. However, as this limit is somewhat easy to
1737	/// hit with template metaprogramming we'd prefer to keep it as large
1738	/// as possible. At the moment it has been left as a non-bitfield since
1739	/// this type safely fits in 64 bits as an unsigned, so there is no reason
1740	/// to introduce the performance impact of a bitfield.
1741	unsigned NumArgs;
1742	};
1743
1744	class DependentTemplateSpecializationTypeBitfields {
1745	friend class DependentTemplateSpecializationType;
1746
1747	unsigned : NumTypeBits;
1748	unsigned : NumTypeWithKeywordBits;
1749
1750	/// The number of template arguments named in this class template
1751	/// specialization, which is expected to be able to hold at least 1024
1752	/// according to [implimits]. However, as this limit is somewhat easy to
1753	/// hit with template metaprogramming we'd prefer to keep it as large
1754	/// as possible. At the moment it has been left as a non-bitfield since
1755	/// this type safely fits in 64 bits as an unsigned, so there is no reason
1756	/// to introduce the performance impact of a bitfield.
1757	unsigned NumArgs;
1758	};
1759
1760	class PackExpansionTypeBitfields {
1761	friend class PackExpansionType;
1762
1763	unsigned : NumTypeBits;
1764
1765	/// The number of expansions that this pack expansion will
1766	/// generate when substituted (+1), which is expected to be able to
1767	/// hold at least 1024 according to [implimits]. However, as this limit
1768	/// is somewhat easy to hit with template metaprogramming we'd prefer to
1769	/// keep it as large as possible. At the moment it has been left as a
1770	/// non-bitfield since this type safely fits in 64 bits as an unsigned, so
1771	/// there is no reason to introduce the performance impact of a bitfield.
1772	///
1773	/// This field will only have a non-zero value when some of the parameter
1774	/// packs that occur within the pattern have been substituted but others
1775	/// have not.
1776	unsigned NumExpansions;
1777	};
1778
1779	union {
1780	TypeBitfields TypeBits;
1781	ArrayTypeBitfields ArrayTypeBits;
1782	ConstantArrayTypeBitfields ConstantArrayTypeBits;
1783	AttributedTypeBitfields AttributedTypeBits;
1784	AutoTypeBitfields AutoTypeBits;
1785	BuiltinTypeBitfields BuiltinTypeBits;
1786	FunctionTypeBitfields FunctionTypeBits;
1787	ObjCObjectTypeBitfields ObjCObjectTypeBits;
1788	ReferenceTypeBitfields ReferenceTypeBits;
1789	TypeWithKeywordBitfields TypeWithKeywordBits;
1790	ElaboratedTypeBitfields ElaboratedTypeBits;
1791	VectorTypeBitfields VectorTypeBits;
1792	SubstTemplateTypeParmPackTypeBitfields SubstTemplateTypeParmPackTypeBits;
1793	TemplateSpecializationTypeBitfields TemplateSpecializationTypeBits;
1794	DependentTemplateSpecializationTypeBitfields
1795	DependentTemplateSpecializationTypeBits;
1796	PackExpansionTypeBitfields PackExpansionTypeBits;
1797	};
1798
1799	private:
1800	template <class T> friend class TypePropertyCache;
1801
1802	/// Set whether this type comes from an AST file.
1803	void setFromAST(bool V = true) const {
1804	TypeBits.FromAST = V;
1805	}
1806
1807	protected:
1808	friend class ASTContext;
1809
1810	Type(TypeClass tc, QualType canon, TypeDependence Dependence)
1811	: ExtQualsTypeCommonBase(this,
1812	canon.isNull() ? QualType(this_(), 0) : canon) {
1813	static_assert(sizeof(*this) <= 8 + sizeof(ExtQualsTypeCommonBase),
1814	"changing bitfields changed sizeof(Type)!");
1815	static_assert(alignof(decltype(this)) % sizeof(void ) == 0,
1816	"Insufficient alignment!");
1817	TypeBits.TC = tc;
1818	TypeBits.Dependence = static_cast<unsigned>(Dependence);
1819	TypeBits.CacheValid = false;
1820	TypeBits.CachedLocalOrUnnamed = false;
1821	TypeBits.CachedLinkage = NoLinkage;
1822	TypeBits.FromAST = false;
1823	}
1824
1825	// silence VC++ warning C4355: 'this' : used in base member initializer list
1826	Type *this_() { return this; }
1827
1828	void setDependence(TypeDependence D) {
1829	TypeBits.Dependence = static_cast<unsigned>(D);
1830	}
1831
1832	void addDependence(TypeDependence D) { setDependence(getDependence() \| D); }
1833
1834	public:
1835	friend class ASTReader;
1836	friend class ASTWriter;
1837	template <class T> friend class serialization::AbstractTypeReader;
1838	template <class T> friend class serialization::AbstractTypeWriter;
1839
1840	Type(const Type &) = delete;
1841	Type(Type &&) = delete;
1842	Type &operator=(const Type &) = delete;
1843	Type &operator=(Type &&) = delete;
1844
1845	TypeClass getTypeClass() const { return static_cast<TypeClass>(TypeBits.TC); }
1846
1847	/// Whether this type comes from an AST file.
1848	bool isFromAST() const { return TypeBits.FromAST; }
1849
1850	/// Whether this type is or contains an unexpanded parameter
1851	/// pack, used to support C++0x variadic templates.
1852	///
1853	/// A type that contains a parameter pack shall be expanded by the
1854	/// ellipsis operator at some point. For example, the typedef in the
1855	/// following example contains an unexpanded parameter pack 'T':
1856	///
1857	/// \code
1858	/// template<typename ...T>
1859	/// struct X {
1860	/// typedef T* pointer_types; // ill-formed; T is a parameter pack.
1861	/// };
1862	/// \endcode
1863	///
1864	/// Note that this routine does not specify which
1865	bool containsUnexpandedParameterPack() const {
1866	return getDependence() & TypeDependence::UnexpandedPack;
1867	}
1868
1869	/// Determines if this type would be canonical if it had no further
1870	/// qualification.
1871	bool isCanonicalUnqualified() const {
1872	return CanonicalType == QualType(this, 0);
1873	}
1874
1875	/// Pull a single level of sugar off of this locally-unqualified type.
1876	/// Users should generally prefer SplitQualType::getSingleStepDesugaredType()
1877	/// or QualType::getSingleStepDesugaredType(const ASTContext&).
1878	QualType getLocallyUnqualifiedSingleStepDesugaredType() const;
1879
1880	/// As an extension, we classify types as one of "sized" or "sizeless";
1881	/// every type is one or the other. Standard types are all sized;
1882	/// sizeless types are purely an extension.
1883	///
1884	/// Sizeless types contain data with no specified size, alignment,
1885	/// or layout.
1886	bool isSizelessType() const;
1887	bool isSizelessBuiltinType() const;
1888
1889	/// Determines if this is a sizeless type supported by the
1890	/// 'arm_sve_vector_bits' type attribute, which can be applied to a single
1891	/// SVE vector or predicate, excluding tuple types such as svint32x4_t.
1892	bool isVLSTBuiltinType() const;
1893
1894	/// Returns the representative type for the element of an SVE builtin type.
1895	/// This is used to represent fixed-length SVE vectors created with the
1896	/// 'arm_sve_vector_bits' type attribute as VectorType.
1897	QualType getSveEltType(const ASTContext &Ctx) const;
1898
1899	/// Types are partitioned into 3 broad categories (C99 6.2.5p1):
1900	/// object types, function types, and incomplete types.
1901
1902	/// Return true if this is an incomplete type.
1903	/// A type that can describe objects, but which lacks information needed to
1904	/// determine its size (e.g. void, or a fwd declared struct). Clients of this
1905	/// routine will need to determine if the size is actually required.
1906	///
1907	/// Def If non-null, and the type refers to some kind of declaration
1908	/// that can be completed (such as a C struct, C++ class, or Objective-C
1909	/// class), will be set to the declaration.
1910	bool isIncompleteType(NamedDecl **Def = nullptr) const;
1911
1912	/// Return true if this is an incomplete or object
1913	/// type, in other words, not a function type.
1914	bool isIncompleteOrObjectType() const {
1915	return !isFunctionType();
1916	}
1917
1918	/// Determine whether this type is an object type.
1919	bool isObjectType() const {
1920	// C++ [basic.types]p8:
1921	// An object type is a (possibly cv-qualified) type that is not a
1922	// function type, not a reference type, and not a void type.
1923	return !isReferenceType() && !isFunctionType() && !isVoidType();
1924	}
1925
1926	/// Return true if this is a literal type
1927	/// (C++11 [basic.types]p10)
1928	bool isLiteralType(const ASTContext &Ctx) const;
1929
1930	/// Determine if this type is a structural type, per C++20 [temp.param]p7.
1931	bool isStructuralType() const;
1932
1933	/// Test if this type is a standard-layout type.
1934	/// (C++0x [basic.type]p9)
1935	bool isStandardLayoutType() const;
1936
1937	/// Helper methods to distinguish type categories. All type predicates
1938	/// operate on the canonical type, ignoring typedefs and qualifiers.
1939
1940	/// Returns true if the type is a builtin type.
1941	bool isBuiltinType() const;
1942
1943	/// Test for a particular builtin type.
1944	bool isSpecificBuiltinType(unsigned K) const;
1945
1946	/// Test for a type which does not represent an actual type-system type but
1947	/// is instead used as a placeholder for various convenient purposes within
1948	/// Clang. All such types are BuiltinTypes.
1949	bool isPlaceholderType() const;
1950	const BuiltinType *getAsPlaceholderType() const;
1951
1952	/// Test for a specific placeholder type.
1953	bool isSpecificPlaceholderType(unsigned K) const;
1954
1955	/// Test for a placeholder type other than Overload; see
1956	/// BuiltinType::isNonOverloadPlaceholderType.
1957	bool isNonOverloadPlaceholderType() const;
1958
1959	/// isIntegerType() does not include complex integers (a GCC extension).
1960	/// isComplexIntegerType() can be used to test for complex integers.
1961	bool isIntegerType() const; // C99 6.2.5p17 (int, char, bool, enum)
1962	bool isEnumeralType() const;
1963
1964	/// Determine whether this type is a scoped enumeration type.
1965	bool isScopedEnumeralType() const;
1966	bool isBooleanType() const;
1967	bool isCharType() const;
1968	bool isWideCharType() const;
1969	bool isChar8Type() const;
1970	bool isChar16Type() const;
1971	bool isChar32Type() const;
1972	bool isAnyCharacterType() const;
1973	bool isIntegralType(const ASTContext &Ctx) const;
1974
1975	/// Determine whether this type is an integral or enumeration type.
1976	bool isIntegralOrEnumerationType() const;
1977
1978	/// Determine whether this type is an integral or unscoped enumeration type.
1979	bool isIntegralOrUnscopedEnumerationType() const;
1980	bool isUnscopedEnumerationType() const;
1981
1982	/// Floating point categories.
1983	bool isRealFloatingType() const; // C99 6.2.5p10 (float, double, long double)
1984	/// isComplexType() does not include complex integers (a GCC extension).
1985	/// isComplexIntegerType() can be used to test for complex integers.
1986	bool isComplexType() const; // C99 6.2.5p11 (complex)
1987	bool isAnyComplexType() const; // C99 6.2.5p11 (complex) + Complex Int.
1988	bool isFloatingType() const; // C99 6.2.5p11 (real floating + complex)
1989	bool isHalfType() const; // OpenCL 6.1.1.1, NEON (IEEE 754-2008 half)
1990	bool isFloat16Type() const; // C11 extension ISO/IEC TS 18661
1991	bool isBFloat16Type() const;
1992	bool isFloat128Type() const;
1993	bool isRealType() const; // C99 6.2.5p17 (real floating + integer)
1994	bool isArithmeticType() const; // C99 6.2.5p18 (integer + floating)
1995	bool isVoidType() const; // C99 6.2.5p19
1996	bool isScalarType() const; // C99 6.2.5p21 (arithmetic + pointers)
1997	bool isAggregateType() const;
1998	bool isFundamentalType() const;
1999	bool isCompoundType() const;
2000
2001	// Type Predicates: Check to see if this type is structurally the specified
2002	// type, ignoring typedefs and qualifiers.
2003	bool isFunctionType() const;
2004	bool isFunctionNoProtoType() const { return getAs<FunctionNoProtoType>(); }
2005	bool isFunctionProtoType() const { return getAs<FunctionProtoType>(); }
2006	bool isPointerType() const;
2007	bool isAnyPointerType() const; // Any C pointer or ObjC object pointer
2008	bool isBlockPointerType() const;
2009	bool isVoidPointerType() const;
2010	bool isReferenceType() const;
2011	bool isLValueReferenceType() const;
2012	bool isRValueReferenceType() const;
2013	bool isObjectPointerType() const;
2014	bool isFunctionPointerType() const;
2015	bool isFunctionReferenceType() const;
2016	bool isMemberPointerType() const;
2017	bool isMemberFunctionPointerType() const;
2018	bool isMemberDataPointerType() const;
2019	bool isArrayType() const;
2020	bool isConstantArrayType() const;
2021	bool isIncompleteArrayType() const;
2022	bool isVariableArrayType() const;
2023	bool isDependentSizedArrayType() const;
2024	bool isRecordType() const;
2025	bool isClassType() const;
2026	bool isStructureType() const;
2027	bool isObjCBoxableRecordType() const;
2028	bool isInterfaceType() const;
2029	bool isStructureOrClassType() const;
2030	bool isUnionType() const;
2031	bool isComplexIntegerType() const; // GCC _Complex integer type.
2032	bool isVectorType() const; // GCC vector type.
2033	bool isExtVectorType() const; // Extended vector type.
2034	bool isMatrixType() const; // Matrix type.
2035	bool isConstantMatrixType() const; // Constant matrix type.
2036	bool isDependentAddressSpaceType() const; // value-dependent address space qualifier
2037	bool isObjCObjectPointerType() const; // pointer to ObjC object
2038	bool isObjCRetainableType() const; // ObjC object or block pointer
2039	bool isObjCLifetimeType() const; // (array of)* retainable type
2040	bool isObjCIndirectLifetimeType() const; // (pointer to)* lifetime type
2041	bool isObjCNSObjectType() const; // __attribute__((NSObject))
2042	bool isObjCIndependentClassType() const; // __attribute__((objc_independent_class))
2043	// FIXME: change this to 'raw' interface type, so we can used 'interface' type
2044	// for the common case.
2045	bool isObjCObjectType() const; // NSString or typeof(*(id)0)
2046	bool isObjCQualifiedInterfaceType() const; // NSString<foo>
2047	bool isObjCQualifiedIdType() const; // id<foo>
2048	bool isObjCQualifiedClassType() const; // Class<foo>
2049	bool isObjCObjectOrInterfaceType() const;
2050	bool isObjCIdType() const; // id
2051	bool isDecltypeType() const;
2052	/// Was this type written with the special inert-in-ARC __unsafe_unretained
2053	/// qualifier?
2054	///
2055	/// This approximates the answer to the following question: if this
2056	/// translation unit were compiled in ARC, would this type be qualified
2057	/// with __unsafe_unretained?
2058	bool isObjCInertUnsafeUnretainedType() const {
2059	return hasAttr(attr::ObjCInertUnsafeUnretained);
2060	}
2061
2062	/// Whether the type is Objective-C 'id' or a __kindof type of an
2063	/// object type, e.g., __kindof NSView * or __kindof id
2064	/// <NSCopying>.
2065	///
2066	/// \param bound Will be set to the bound on non-id subtype types,
2067	/// which will be (possibly specialized) Objective-C class type, or
2068	/// null for 'id.
2069	bool isObjCIdOrObjectKindOfType(const ASTContext &ctx,
2070	const ObjCObjectType *&bound) const;
2071
2072	bool isObjCClassType() const; // Class
2073
2074	/// Whether the type is Objective-C 'Class' or a __kindof type of an
2075	/// Class type, e.g., __kindof Class <NSCopying>.
2076	///
2077	/// Unlike \c isObjCIdOrObjectKindOfType, there is no relevant bound
2078	/// here because Objective-C's type system cannot express "a class
2079	/// object for a subclass of NSFoo".
2080	bool isObjCClassOrClassKindOfType() const;
2081
2082	bool isBlockCompatibleObjCPointerType(ASTContext &ctx) const;
2083	bool isObjCSelType() const; // Class
2084	bool isObjCBuiltinType() const; // 'id' or 'Class'
2085	bool isObjCARCBridgableType() const;
2086	bool isCARCBridgableType() const;
2087	bool isTemplateTypeParmType() const; // C++ template type parameter
2088	bool isNullPtrType() const; // C++11 std::nullptr_t
2089	bool isNothrowT() const; // C++ std::nothrow_t
2090	bool isAlignValT() const; // C++17 std::align_val_t
2091	bool isStdByteType() const; // C++17 std::byte
2092	bool isAtomicType() const; // C11 _Atomic()
2093	bool isUndeducedAutoType() const; // C++11 auto or
2094	// C++14 decltype(auto)
2095
2096	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
2097	bool is##Id##Type() const;
2098	#include "clang/Basic/OpenCLImageTypes.def"
2099
2100	bool isImageType() const; // Any OpenCL image type
2101
2102	bool isSamplerT() const; // OpenCL sampler_t
2103	bool isEventT() const; // OpenCL event_t
2104	bool isClkEventT() const; // OpenCL clk_event_t
2105	bool isQueueT() const; // OpenCL queue_t
2106	bool isReserveIDT() const; // OpenCL reserve_id_t
2107
2108	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
2109	bool is##Id##Type() const;
2110	#include "clang/Basic/OpenCLExtensionTypes.def"
2111	// Type defined in cl_intel_device_side_avc_motion_estimation OpenCL extension
2112	bool isOCLIntelSubgroupAVCType() const;
2113	bool isOCLExtOpaqueType() const; // Any OpenCL extension type
2114
2115	bool isPipeType() const; // OpenCL pipe type
2116	bool isExtIntType() const; // Extended Int Type
2117	bool isOpenCLSpecificType() const; // Any OpenCL specific type
2118
2119	/// Determines if this type, which must satisfy
2120	/// isObjCLifetimeType(), is implicitly __unsafe_unretained rather
2121	/// than implicitly __strong.
2122	bool isObjCARCImplicitlyUnretainedType() const;
2123
2124	/// Check if the type is the CUDA device builtin surface type.
2125	bool isCUDADeviceBuiltinSurfaceType() const;
2126	/// Check if the type is the CUDA device builtin texture type.
2127	bool isCUDADeviceBuiltinTextureType() const;
2128
2129	/// Return the implicit lifetime for this type, which must not be dependent.
2130	Qualifiers::ObjCLifetime getObjCARCImplicitLifetime() const;
2131
2132	enum ScalarTypeKind {
2133	STK_CPointer,
2134	STK_BlockPointer,
2135	STK_ObjCObjectPointer,
2136	STK_MemberPointer,
2137	STK_Bool,
2138	STK_Integral,
2139	STK_Floating,
2140	STK_IntegralComplex,
2141	STK_FloatingComplex,
2142	STK_FixedPoint
2143	};
2144
2145	/// Given that this is a scalar type, classify it.
2146	ScalarTypeKind getScalarTypeKind() const;
2147
2148	TypeDependence getDependence() const {
2149	return static_cast<TypeDependence>(TypeBits.Dependence);
2150	}
2151
2152	/// Whether this type is an error type.
2153	bool containsErrors() const {
2154	return getDependence() & TypeDependence::Error;
2155	}
2156
2157	/// Whether this type is a dependent type, meaning that its definition
2158	/// somehow depends on a template parameter (C++ [temp.dep.type]).
2159	bool isDependentType() const {
2160	return getDependence() & TypeDependence::Dependent;
2161	}
2162
2163	/// Determine whether this type is an instantiation-dependent type,
2164	/// meaning that the type involves a template parameter (even if the
2165	/// definition does not actually depend on the type substituted for that
2166	/// template parameter).
2167	bool isInstantiationDependentType() const {
2168	return getDependence() & TypeDependence::Instantiation;
2169	}
2170
2171	/// Determine whether this type is an undeduced type, meaning that
2172	/// it somehow involves a C++11 'auto' type or similar which has not yet been
2173	/// deduced.
2174	bool isUndeducedType() const;
2175
2176	/// Whether this type is a variably-modified type (C99 6.7.5).
2177	bool isVariablyModifiedType() const {
2178	return getDependence() & TypeDependence::VariablyModified;
2179	}
2180
2181	/// Whether this type involves a variable-length array type
2182	/// with a definite size.
2183	bool hasSizedVLAType() const;
2184
2185	/// Whether this type is or contains a local or unnamed type.
2186	bool hasUnnamedOrLocalType() const;
2187
2188	bool isOverloadableType() const;
2189
2190	/// Determine wither this type is a C++ elaborated-type-specifier.
2191	bool isElaboratedTypeSpecifier() const;
2192
2193	bool canDecayToPointerType() const;
2194
2195	/// Whether this type is represented natively as a pointer. This includes
2196	/// pointers, references, block pointers, and Objective-C interface,
2197	/// qualified id, and qualified interface types, as well as nullptr_t.
2198	bool hasPointerRepresentation() const;
2199
2200	/// Whether this type can represent an objective pointer type for the
2201	/// purpose of GC'ability
2202	bool hasObjCPointerRepresentation() const;
2203
2204	/// Determine whether this type has an integer representation
2205	/// of some sort, e.g., it is an integer type or a vector.
2206	bool hasIntegerRepresentation() const;
2207
2208	/// Determine whether this type has an signed integer representation
2209	/// of some sort, e.g., it is an signed integer type or a vector.
2210	bool hasSignedIntegerRepresentation() const;
2211
2212	/// Determine whether this type has an unsigned integer representation
2213	/// of some sort, e.g., it is an unsigned integer type or a vector.
2214	bool hasUnsignedIntegerRepresentation() const;
2215
2216	/// Determine whether this type has a floating-point representation
2217	/// of some sort, e.g., it is a floating-point type or a vector thereof.
2218	bool hasFloatingRepresentation() const;
2219
2220	// Type Checking Functions: Check to see if this type is structurally the
2221	// specified type, ignoring typedefs and qualifiers, and return a pointer to
2222	// the best type we can.
2223	const RecordType *getAsStructureType() const;
2224	/// NOTE: getAs*ArrayType are methods on ASTContext.
2225	const RecordType *getAsUnionType() const;
2226	const ComplexType *getAsComplexIntegerType() const; // GCC complex int type.
2227	const ObjCObjectType *getAsObjCInterfaceType() const;
2228
2229	// The following is a convenience method that returns an ObjCObjectPointerType
2230	// for object declared using an interface.
2231	const ObjCObjectPointerType *getAsObjCInterfacePointerType() const;
2232	const ObjCObjectPointerType *getAsObjCQualifiedIdType() const;
2233	const ObjCObjectPointerType *getAsObjCQualifiedClassType() const;
2234	const ObjCObjectType *getAsObjCQualifiedInterfaceType() const;
2235
2236	/// Retrieves the CXXRecordDecl that this type refers to, either
2237	/// because the type is a RecordType or because it is the injected-class-name
2238	/// type of a class template or class template partial specialization.
2239	CXXRecordDecl *getAsCXXRecordDecl() const;
2240
2241	/// Retrieves the RecordDecl this type refers to.
2242	RecordDecl *getAsRecordDecl() const;
2243
2244	/// Retrieves the TagDecl that this type refers to, either
2245	/// because the type is a TagType or because it is the injected-class-name
2246	/// type of a class template or class template partial specialization.
2247	TagDecl *getAsTagDecl() const;
2248
2249	/// If this is a pointer or reference to a RecordType, return the
2250	/// CXXRecordDecl that the type refers to.
2251	///
2252	/// If this is not a pointer or reference, or the type being pointed to does
2253	/// not refer to a CXXRecordDecl, returns NULL.
2254	const CXXRecordDecl *getPointeeCXXRecordDecl() const;
2255
2256	/// Get the DeducedType whose type will be deduced for a variable with
2257	/// an initializer of this type. This looks through declarators like pointer
2258	/// types, but not through decltype or typedefs.
2259	DeducedType *getContainedDeducedType() const;
2260
2261	/// Get the AutoType whose type will be deduced for a variable with
2262	/// an initializer of this type. This looks through declarators like pointer
2263	/// types, but not through decltype or typedefs.
2264	AutoType *getContainedAutoType() const {
2265	return dyn_cast_or_null<AutoType>(getContainedDeducedType());
2266	}
2267
2268	/// Determine whether this type was written with a leading 'auto'
2269	/// corresponding to a trailing return type (possibly for a nested
2270	/// function type within a pointer to function type or similar).
2271	bool hasAutoForTrailingReturnType() const;
2272
2273	/// Member-template getAs<specific type>'. Look through sugar for
2274	/// an instance of \<specific type>. This scheme will eventually
2275	/// replace the specific getAsXXXX methods above.
2276	///
2277	/// There are some specializations of this member template listed
2278	/// immediately following this class.
2279	template <typename T> const T *getAs() const;
2280
2281	/// Member-template getAsAdjusted<specific type>. Look through specific kinds
2282	/// of sugar (parens, attributes, etc) for an instance of \<specific type>.
2283	/// This is used when you need to walk over sugar nodes that represent some
2284	/// kind of type adjustment from a type that was written as a \<specific type>
2285	/// to another type that is still canonically a \<specific type>.
2286	template <typename T> const T *getAsAdjusted() const;
2287
2288	/// A variant of getAs<> for array types which silently discards
2289	/// qualifiers from the outermost type.
2290	const ArrayType *getAsArrayTypeUnsafe() const;
2291
2292	/// Member-template castAs<specific type>. Look through sugar for
2293	/// the underlying instance of \<specific type>.
2294	///
2295	/// This method has the same relationship to getAs<T> as cast<T> has
2296	/// to dyn_cast<T>; which is to say, the underlying type must
2297	/// have the intended type, and this method will never return null.
2298	template <typename T> const T *castAs() const;
2299
2300	/// A variant of castAs<> for array type which silently discards
2301	/// qualifiers from the outermost type.
2302	const ArrayType *castAsArrayTypeUnsafe() const;
2303
2304	/// Determine whether this type had the specified attribute applied to it
2305	/// (looking through top-level type sugar).
2306	bool hasAttr(attr::Kind AK) const;
2307
2308	/// Get the base element type of this type, potentially discarding type
2309	/// qualifiers. This should never be used when type qualifiers
2310	/// are meaningful.
2311	const Type *getBaseElementTypeUnsafe() const;
2312
2313	/// If this is an array type, return the element type of the array,
2314	/// potentially with type qualifiers missing.
2315	/// This should never be used when type qualifiers are meaningful.
2316	const Type *getArrayElementTypeNoTypeQual() const;
2317
2318	/// If this is a pointer type, return the pointee type.
2319	/// If this is an array type, return the array element type.
2320	/// This should never be used when type qualifiers are meaningful.
2321	const Type *getPointeeOrArrayElementType() const;
2322
2323	/// If this is a pointer, ObjC object pointer, or block
2324	/// pointer, this returns the respective pointee.
2325	QualType getPointeeType() const;
2326
2327	/// Return the specified type with any "sugar" removed from the type,
2328	/// removing any typedefs, typeofs, etc., as well as any qualifiers.
2329	const Type *getUnqualifiedDesugaredType() const;
2330
2331	/// More type predicates useful for type checking/promotion
2332	bool isPromotableIntegerType() const; // C99 6.3.1.1p2
2333
2334	/// Return true if this is an integer type that is
2335	/// signed, according to C99 6.2.5p4 [char, signed char, short, int, long..],
2336	/// or an enum decl which has a signed representation.
2337	bool isSignedIntegerType() const;
2338
2339	/// Return true if this is an integer type that is
2340	/// unsigned, according to C99 6.2.5p6 [which returns true for _Bool],
2341	/// or an enum decl which has an unsigned representation.
2342	bool isUnsignedIntegerType() const;
2343
2344	/// Determines whether this is an integer type that is signed or an
2345	/// enumeration types whose underlying type is a signed integer type.
2346	bool isSignedIntegerOrEnumerationType() const;
2347
2348	/// Determines whether this is an integer type that is unsigned or an
2349	/// enumeration types whose underlying type is a unsigned integer type.
2350	bool isUnsignedIntegerOrEnumerationType() const;
2351
2352	/// Return true if this is a fixed point type according to
2353	/// ISO/IEC JTC1 SC22 WG14 N1169.
2354	bool isFixedPointType() const;
2355
2356	/// Return true if this is a fixed point or integer type.
2357	bool isFixedPointOrIntegerType() const;
2358
2359	/// Return true if this is a saturated fixed point type according to
2360	/// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2361	bool isSaturatedFixedPointType() const;
2362
2363	/// Return true if this is a saturated fixed point type according to
2364	/// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2365	bool isUnsaturatedFixedPointType() const;
2366
2367	/// Return true if this is a fixed point type that is signed according
2368	/// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2369	bool isSignedFixedPointType() const;
2370
2371	/// Return true if this is a fixed point type that is unsigned according
2372	/// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2373	bool isUnsignedFixedPointType() const;
2374
2375	/// Return true if this is not a variable sized type,
2376	/// according to the rules of C99 6.7.5p3. It is not legal to call this on
2377	/// incomplete types.
2378	bool isConstantSizeType() const;
2379
2380	/// Returns true if this type can be represented by some
2381	/// set of type specifiers.
2382	bool isSpecifierType() const;
2383
2384	/// Determine the linkage of this type.
2385	Linkage getLinkage() const;
2386
2387	/// Determine the visibility of this type.
2388	Visibility getVisibility() const {
2389	return getLinkageAndVisibility().getVisibility();
2390	}
2391
2392	/// Return true if the visibility was explicitly set is the code.
2393	bool isVisibilityExplicit() const {
2394	return getLinkageAndVisibility().isVisibilityExplicit();
2395	}
2396
2397	/// Determine the linkage and visibility of this type.
2398	LinkageInfo getLinkageAndVisibility() const;
2399
2400	/// True if the computed linkage is valid. Used for consistency
2401	/// checking. Should always return true.
2402	bool isLinkageValid() const;
2403
2404	/// Determine the nullability of the given type.
2405	///
2406	/// Note that nullability is only captured as sugar within the type
2407	/// system, not as part of the canonical type, so nullability will
2408	/// be lost by canonicalization and desugaring.
2409	Optional<NullabilityKind> getNullability(const ASTContext &context) const;
2410
2411	/// Determine whether the given type can have a nullability
2412	/// specifier applied to it, i.e., if it is any kind of pointer type.
2413	///
2414	/// \param ResultIfUnknown The value to return if we don't yet know whether
2415	/// this type can have nullability because it is dependent.
2416	bool canHaveNullability(bool ResultIfUnknown = true) const;
2417
2418	/// Retrieve the set of substitutions required when accessing a member
2419	/// of the Objective-C receiver type that is declared in the given context.
2420	///
2421	/// \c *this is the type of the object we're operating on, e.g., the
2422	/// receiver for a message send or the base of a property access, and is
2423	/// expected to be of some object or object pointer type.
2424	///
2425	/// \param dc The declaration context for which we are building up a
2426	/// substitution mapping, which should be an Objective-C class, extension,
2427	/// category, or method within.
2428	///
2429	/// \returns an array of type arguments that can be substituted for
2430	/// the type parameters of the given declaration context in any type described
2431	/// within that context, or an empty optional to indicate that no
2432	/// substitution is required.
2433	Optional<ArrayRef<QualType>>
2434	getObjCSubstitutions(const DeclContext *dc) const;
2435
2436	/// Determines if this is an ObjC interface type that may accept type
2437	/// parameters.
2438	bool acceptsObjCTypeParams() const;
2439
2440	const char *getTypeClassName() const;
2441
2442	QualType getCanonicalTypeInternal() const {
2443	return CanonicalType;
2444	}
2445
2446	CanQualType getCanonicalTypeUnqualified() const; // in CanonicalType.h
2447	void dump() const;
2448	void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
2449	};
2450
2451	/// This will check for a TypedefType by removing any existing sugar
2452	/// until it reaches a TypedefType or a non-sugared type.
2453	template <> const TypedefType *Type::getAs() const;
2454
2455	/// This will check for a TemplateSpecializationType by removing any
2456	/// existing sugar until it reaches a TemplateSpecializationType or a
2457	/// non-sugared type.
2458	template <> const TemplateSpecializationType *Type::getAs() const;
2459
2460	/// This will check for an AttributedType by removing any existing sugar
2461	/// until it reaches an AttributedType or a non-sugared type.
2462	template <> const AttributedType *Type::getAs() const;
2463
2464	// We can do canonical leaf types faster, because we don't have to
2465	// worry about preserving child type decoration.
2466	#define TYPE(Class, Base)
2467	#define LEAF_TYPE(Class) \
2468	template <> inline const Class##Type *Type::getAs() const { \
2469	return dyn_cast<Class##Type>(CanonicalType); \
2470	} \
2471	template <> inline const Class##Type *Type::castAs() const { \
2472	return cast<Class##Type>(CanonicalType); \
2473	}
2474	#include "clang/AST/TypeNodes.inc"
2475
2476	/// This class is used for builtin types like 'int'. Builtin
2477	/// types are always canonical and have a literal name field.
2478	class BuiltinType : public Type {
2479	public:
2480	enum Kind {
2481	// OpenCL image types
2482	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) Id,
2483	#include "clang/Basic/OpenCLImageTypes.def"
2484	// OpenCL extension types
2485	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) Id,
2486	#include "clang/Basic/OpenCLExtensionTypes.def"
2487	// SVE Types
2488	#define SVE_TYPE(Name, Id, SingletonId) Id,
2489	#include "clang/Basic/AArch64SVEACLETypes.def"
2490	// All other builtin types
2491	#define BUILTIN_TYPE(Id, SingletonId) Id,
2492	#define LAST_BUILTIN_TYPE(Id) LastKind = Id
2493	#include "clang/AST/BuiltinTypes.def"
2494	};
2495
2496	private:
2497	friend class ASTContext; // ASTContext creates these.
2498
2499	BuiltinType(Kind K)
2500	: Type(Builtin, QualType(),
2501	K == Dependent ? TypeDependence::DependentInstantiation
2502	: TypeDependence::None) {
2503	BuiltinTypeBits.Kind = K;
2504	}
2505
2506	public:
2507	Kind getKind() const { return static_cast<Kind>(BuiltinTypeBits.Kind); }
2508	StringRef getName(const PrintingPolicy &Policy) const;
2509
2510	const char *getNameAsCString(const PrintingPolicy &Policy) const {
2511	// The StringRef is null-terminated.
2512	StringRef str = getName(Policy);
2513	assert(!str.empty() && str.data()[str.size()] == '\0')((!str.empty() && str.data()[str.size()] == '\0') ? static_cast <void> (0) : __assert_fail ("!str.empty() && str.data()[str.size()] == '\\0'" , "/build/llvm-toolchain-snapshot-12~++20200926111128+c6c5629f2fb/clang/include/clang/AST/Type.h" , 2513, __PRETTY_FUNCTION__));
2514	return str.data();
2515	}
2516
2517	bool isSugared() const { return false; }
2518	QualType desugar() const { return QualType(this, 0); }
2519
2520	bool isInteger() const {
2521	return getKind() >= Bool && getKind() <= Int128;
2522	}
2523
2524	bool isSignedInteger() const {
2525	return getKind() >= Char_S && getKind() <= Int128;
2526	}
2527
2528	bool isUnsignedInteger() const {
2529	return getKind() >= Bool && getKind() <= UInt128;
2530	}
2531
2532	bool isFloatingPoint() const {
2533	return getKind() >= Half && getKind() <= Float128;
2534	}
2535
2536	/// Determines whether the given kind corresponds to a placeholder type.
2537	static bool isPlaceholderTypeKind(Kind K) {
2538	return K >= Overload;
2539	}
2540
2541	/// Determines whether this type is a placeholder type, i.e. a type
2542	/// which cannot appear in arbitrary positions in a fully-formed
2543	/// expression.
2544	bool isPlaceholderType() const {
2545	return isPlaceholderTypeKind(getKind());
2546	}
2547
2548	/// Determines whether this type is a placeholder type other than
2549	/// Overload. Most placeholder types require only syntactic
2550	/// information about their context in order to be resolved (e.g.
2551	/// whether it is a call expression), which means they can (and
2552	/// should) be resolved in an earlier "phase" of analysis.
2553	/// Overload expressions sometimes pick up further information
2554	/// from their context, like whether the context expects a
2555	/// specific function-pointer type, and so frequently need
2556	/// special treatment.
2557	bool isNonOverloadPlaceholderType() const {
2558	return getKind() > Overload;
2559	}
2560
2561	static bool classof(const Type *T) { return T->getTypeClass() == Builtin; }
2562	};
2563
2564	/// Complex values, per C99 6.2.5p11. This supports the C99 complex
2565	/// types (_Complex float etc) as well as the GCC integer complex extensions.
2566	class ComplexType : public Type, public llvm::FoldingSetNode {
2567	friend class ASTContext; // ASTContext creates these.
2568
2569	QualType ElementType;
2570
2571	ComplexType(QualType Element, QualType CanonicalPtr)
2572	: Type(Complex, CanonicalPtr, Element->getDependence()),
2573	ElementType(Element) {}
2574
2575	public:
2576	QualType getElementType() const { return ElementType; }
2577
2578	bool isSugared() const { return false; }
2579	QualType desugar() const { return QualType(this, 0); }
2580
2581	void Profile(llvm::FoldingSetNodeID &ID) {
2582	Profile(ID, getElementType());
2583	}
2584
2585	static void Profile(llvm::FoldingSetNodeID &ID, QualType Element) {
2586	ID.AddPointer(Element.getAsOpaquePtr());
2587	}
2588
2589	static bool classof(const Type *T) { return T->getTypeClass() == Complex; }
2590	};
2591
2592	/// Sugar for parentheses used when specifying types.
2593	class ParenType : public Type, public llvm::FoldingSetNode {
2594	friend class ASTContext; // ASTContext creates these.
2595
2596	QualType Inner;
2597
2598	ParenType(QualType InnerType, QualType CanonType)
2599	: Type(Paren, CanonType, InnerType->getDependence()), Inner(InnerType) {}
2600
2601	public:
2602	QualType getInnerType() const { return Inner; }
2603
2604	bool isSugared() const { return true; }
2605	QualType desugar() const { return getInnerType(); }
2606
2607	void Profile(llvm::FoldingSetNodeID &ID) {
2608	Profile(ID, getInnerType());
2609	}
2610
2611	static void Profile(llvm::FoldingSetNodeID &ID, QualType Inner) {
2612	Inner.Profile(ID);
2613	}
2614
2615	static bool classof(const Type *T) { return T->getTypeClass() == Paren; }
2616	};
2617
2618	/// PointerType - C99 6.7.5.1 - Pointer Declarators.
2619	class PointerType : public Type, public llvm::FoldingSetNode {
2620	friend class ASTContext; // ASTContext creates these.
2621
2622	QualType PointeeType;
2623
2624	PointerType(QualType Pointee, QualType CanonicalPtr)
2625	: Type(Pointer, CanonicalPtr, Pointee->getDependence()),
2626	PointeeType(Pointee) {}
2627
2628	public:
2629	QualType getPointeeType() const { return PointeeType; }
2630
2631	bool isSugared() const { return false; }
2632	QualType desugar() const { return QualType(this, 0); }
2633
2634	void Profile(llvm::FoldingSetNodeID &ID) {
2635	Profile(ID, getPointeeType());
2636	}
2637
2638	static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2639	ID.AddPointer(Pointee.getAsOpaquePtr());
2640	}
2641
2642	static bool classof(const Type *T) { return T->getTypeClass() == Pointer; }
2643	};
2644
2645	/// Represents a type which was implicitly adjusted by the semantic
2646	/// engine for arbitrary reasons. For example, array and function types can
2647	/// decay, and function types can have their calling conventions adjusted.
2648	class AdjustedType : public Type, public llvm::FoldingSetNode {
2649	QualType OriginalTy;
2650	QualType AdjustedTy;
2651
2652	protected:
2653	friend class ASTContext; // ASTContext creates these.
2654
2655	AdjustedType(TypeClass TC, QualType OriginalTy, QualType AdjustedTy,
2656	QualType CanonicalPtr)
2657	: Type(TC, CanonicalPtr, OriginalTy->getDependence()),
2658	OriginalTy(OriginalTy), AdjustedTy(AdjustedTy) {}
2659
2660	public:
2661	QualType getOriginalType() const { return OriginalTy; }
2662	QualType getAdjustedType() const { return AdjustedTy; }
2663
2664	bool isSugared() const { return true; }
2665	QualType desugar() const { return AdjustedTy; }
2666
2667	void Profile(llvm::FoldingSetNodeID &ID) {
2668	Profile(ID, OriginalTy, AdjustedTy);
2669	}
2670
2671	static void Profile(llvm::FoldingSetNodeID &ID, QualType Orig, QualType New) {
2672	ID.AddPointer(Orig.getAsOpaquePtr());
2673	ID.AddPointer(New.getAsOpaquePtr());
2674	}
2675
2676	static bool classof(const Type *T) {
2677	return T->getTypeClass() == Adjusted \|\| T->getTypeClass() == Decayed;
2678	}
2679	};
2680
2681	/// Represents a pointer type decayed from an array or function type.
2682	class DecayedType : public AdjustedType {
2683	friend class ASTContext; // ASTContext creates these.
2684
2685	inline
2686	DecayedType(QualType OriginalType, QualType Decayed, QualType Canonical);
2687
2688	public:
2689	QualType getDecayedType() const { return getAdjustedType(); }
2690
2691	inline QualType getPointeeType() const;
2692
2693	static bool classof(const Type *T) { return T->getTypeClass() == Decayed; }
2694	};
2695
2696	/// Pointer to a block type.
2697	/// This type is to represent types syntactically represented as
2698	/// "void (^)(int)", etc. Pointee is required to always be a function type.
2699	class BlockPointerType : public Type, public llvm::FoldingSetNode {
2700	friend class ASTContext; // ASTContext creates these.
2701
2702	// Block is some kind of pointer type
2703	QualType PointeeType;
2704
2705	BlockPointerType(QualType Pointee, QualType CanonicalCls)
2706	: Type(BlockPointer, CanonicalCls, Pointee->getDependence()),
2707	PointeeType(Pointee) {}
2708
2709	public:
2710	// Get the pointee type. Pointee is required to always be a function type.
2711	QualType getPointeeType() const { return PointeeType; }
2712
2713	bool isSugared() const { return false; }
2714	QualType desugar() const { return QualType(this, 0); }
2715
2716	void Profile(llvm::FoldingSetNodeID &ID) {
2717	Profile(ID, getPointeeType());
2718	}
2719
2720	static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2721	ID.AddPointer(Pointee.getAsOpaquePtr());
2722	}
2723
2724	static bool classof(const Type *T) {
2725	return T->getTypeClass() == BlockPointer;
2726	}
2727	};
2728
2729	/// Base for LValueReferenceType and RValueReferenceType
2730	class ReferenceType : public Type, public llvm::FoldingSetNode {
2731	QualType PointeeType;
2732
2733	protected:
2734	ReferenceType(TypeClass tc, QualType Referencee, QualType CanonicalRef,
2735	bool SpelledAsLValue)
2736	: Type(tc, CanonicalRef, Referencee->getDependence()),
2737	PointeeType(Referencee) {
2738	ReferenceTypeBits.SpelledAsLValue = SpelledAsLValue;
2739	ReferenceTypeBits.InnerRef = Referencee->isReferenceType();
2740	}
2741
2742	public:
2743	bool isSpelledAsLValue() const { return ReferenceTypeBits.SpelledAsLValue; }
2744	bool isInnerRef() const { return ReferenceTypeBits.InnerRef; }
2745
2746	QualType getPointeeTypeAsWritten() const { return PointeeType; }
2747
2748	QualType getPointeeType() const {
2749	// FIXME: this might strip inner qualifiers; okay?
2750	const ReferenceType *T = this;
2751	while (T->isInnerRef())
2752	T = T->PointeeType->castAs<ReferenceType>();
2753	return T->PointeeType;
2754	}
2755
2756	void Profile(llvm::FoldingSetNodeID &ID) {
2757	Profile(ID, PointeeType, isSpelledAsLValue());
2758	}
2759
2760	static void Profile(llvm::FoldingSetNodeID &ID,
2761	QualType Referencee,
2762	bool SpelledAsLValue) {
2763	ID.AddPointer(Referencee.getAsOpaquePtr());
2764	ID.AddBoolean(SpelledAsLValue);
2765	}
2766
2767	static bool classof(const Type *T) {
2768	return T->getTypeClass() == LValueReference \|\|
2769	T->getTypeClass() == RValueReference;
2770	}
2771	};
2772
2773	/// An lvalue reference type, per C++11 [dcl.ref].
2774	class LValueReferenceType : public ReferenceType {
2775	friend class ASTContext; // ASTContext creates these
2776
2777	LValueReferenceType(QualType Referencee, QualType CanonicalRef,
2778	bool SpelledAsLValue)
2779	: ReferenceType(LValueReference, Referencee, CanonicalRef,
2780	SpelledAsLValue) {}
2781
2782	public:
2783	bool isSugared() const { return false; }
2784	QualType desugar() const { return QualType(this, 0); }
2785
2786	static bool classof(const Type *T) {
2787	return T->getTypeClass() == LValueReference;
2788	}
2789	};
2790
2791	/// An rvalue reference type, per C++11 [dcl.ref].
2792	class RValueReferenceType : public ReferenceType {
2793	friend class ASTContext; // ASTContext creates these
2794
2795	RValueReferenceType(QualType Referencee, QualType CanonicalRef)
2796	: ReferenceType(RValueReference, Referencee, CanonicalRef, false) {}
2797
2798	public:
2799	bool isSugared() const { return false; }
2800	QualType desugar() const { return QualType(this, 0); }
2801
2802	static bool classof(const Type *T) {
2803	return T->getTypeClass() == RValueReference;
2804	}
2805	};
2806
2807	/// A pointer to member type per C++ 8.3.3 - Pointers to members.
2808	///
2809	/// This includes both pointers to data members and pointer to member functions.
2810	class MemberPointerType : public Type, public llvm::FoldingSetNode {
2811	friend class ASTContext; // ASTContext creates these.
2812
2813	QualType PointeeType;
2814
2815	/// The class of which the pointee is a member. Must ultimately be a
2816	/// RecordType, but could be a typedef or a template parameter too.
2817	const Type *Class;
2818
2819	MemberPointerType(QualType Pointee, const Type *Cls, QualType CanonicalPtr)
2820	: Type(MemberPointer, CanonicalPtr,
2821	(Cls->getDependence() & ~TypeDependence::VariablyModified) \|
2822	Pointee->getDependence()),
2823	PointeeType(Pointee), Class(Cls) {}
2824
2825	public:
2826	QualType getPointeeType() const { return PointeeType; }
2827
2828	/// Returns true if the member type (i.e. the pointee type) is a
2829	/// function type rather than a data-member type.
2830	bool isMemberFunctionPointer() const {
2831