/build/source/clang/lib/Sema/SemaTemplateInstantiate.cpp

Bug Summary

File:	build/source/clang/lib/Sema/SemaTemplateInstantiate.cpp
Warning:	line 1224, column 15 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 -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name SemaTemplateInstantiate.cpp -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 -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/source/build-llvm -resource-dir /usr/lib/llvm-17/lib/clang/17 -D _DEBUG -D _GLIBCXX_ASSERTIONS -D _GNU_SOURCE -D _LIBCPP_ENABLE_ASSERTIONS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/clang/lib/Sema -I /build/source/clang/lib/Sema -I /build/source/clang/include -I tools/clang/include -I include -I /build/source/llvm/include -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-17/lib/clang/17/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/source/build-llvm=build-llvm -fmacro-prefix-map=/build/source/= -fcoverage-prefix-map=/build/source/build-llvm=build-llvm -fcoverage-prefix-map=/build/source/= -source-date-epoch 1679443490 -O3 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/source/build-llvm -fdebug-prefix-map=/build/source/build-llvm=build-llvm -fdebug-prefix-map=/build/source/= -fdebug-prefix-map=/build/source/build-llvm=build-llvm -fdebug-prefix-map=/build/source/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2023-03-22-005342-16304-1 -x c++ /build/source/clang/lib/Sema/SemaTemplateInstantiate.cpp

/build/source/clang/lib/Sema/SemaTemplateInstantiate.cpp

→

1//===------- SemaTemplateInstantiate.cpp - C++ Template Instantiation ------===/
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//  This file implements C++ template instantiation.
9//
10//===----------------------------------------------------------------------===/

12#include "TreeTransform.h"
13#include "clang/AST/ASTConcept.h"
14#include "clang/AST/ASTConsumer.h"
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/ASTLambda.h"
17#include "clang/AST/ASTMutationListener.h"
18#include "clang/AST/DeclBase.h"
19#include "clang/AST/DeclTemplate.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/ExprConcepts.h"
22#include "clang/AST/PrettyDeclStackTrace.h"
23#include "clang/AST/Type.h"
24#include "clang/AST/TypeVisitor.h"
25#include "clang/Basic/LangOptions.h"
26#include "clang/Basic/Stack.h"
27#include "clang/Basic/TargetInfo.h"
28#include "clang/Sema/DeclSpec.h"
29#include "clang/Sema/Initialization.h"
30#include "clang/Sema/Lookup.h"
31#include "clang/Sema/Sema.h"
32#include "clang/Sema/SemaConcept.h"
33#include "clang/Sema/SemaInternal.h"
34#include "clang/Sema/Template.h"
35#include "clang/Sema/TemplateDeduction.h"
36#include "clang/Sema/TemplateInstCallback.h"
37#include "llvm/Support/ErrorHandling.h"
38#include "llvm/Support/TimeProfiler.h"
39#include <optional>

41using namespace clang;
42using namespace sema;

44//===----------------------------------------------------------------------===/
45// Template Instantiation Support
46//===----------------------------------------------------------------------===/

48namespace {
49namespace TemplateInstArgsHelpers {
50struct Response {
const Decl *NextDecl = nullptr;
bool IsDone = false;
bool ClearRelativeToPrimary = true;
static Response Done() {
  Response R;
  R.IsDone = true;
  return R;
}
static Response ChangeDecl(const Decl *ND) {
  Response R;
  R.NextDecl = ND;
  return R;
}
static Response ChangeDecl(const DeclContext *Ctx) {
  Response R;
  R.NextDecl = Decl::castFromDeclContext(Ctx);
  return R;
}

static Response UseNextDecl(const Decl *CurDecl) {
  return ChangeDecl(CurDecl->getDeclContext());
}

static Response DontClearRelativeToPrimaryNextDecl(const Decl *CurDecl) {
  Response R = Response::UseNextDecl(CurDecl);
  R.ClearRelativeToPrimary = false;
  return R;
}
79};
80// Add template arguments from a variable template instantiation.
81Response
82HandleVarTemplateSpec(const VarTemplateSpecializationDecl *VarTemplSpec,
                    MultiLevelTemplateArgumentList &Result,
                    bool SkipForSpecialization) {
// For a class-scope explicit specialization, there are no template arguments
// at this level, but there may be enclosing template arguments.
if (VarTemplSpec->isClassScopeExplicitSpecialization())
  return Response::DontClearRelativeToPrimaryNextDecl(VarTemplSpec);

// We're done when we hit an explicit specialization.
if (VarTemplSpec->getSpecializationKind() == TSK_ExplicitSpecialization &&
    !isa<VarTemplatePartialSpecializationDecl>(VarTemplSpec))
  return Response::Done();

// If this variable template specialization was instantiated from a
// specialized member that is a variable template, we're done.
assert(VarTemplSpec->getSpecializedTemplate() && "No variable template?")(static_cast <bool> (VarTemplSpec->getSpecializedTemplate
() && "No variable template?") ? void (0) : __assert_fail
 ("VarTemplSpec->getSpecializedTemplate() && \"No variable template?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 97, __extension__
 __PRETTY_FUNCTION__));
llvm::PointerUnion<VarTemplateDecl *, VarTemplatePartialSpecializationDecl *>
    Specialized = VarTemplSpec->getSpecializedTemplateOrPartial();
if (VarTemplatePartialSpecializationDecl *Partial =
        Specialized.dyn_cast<VarTemplatePartialSpecializationDecl *>()) {
  if (!SkipForSpecialization)
    Result.addOuterTemplateArguments(
        Partial, VarTemplSpec->getTemplateInstantiationArgs().asArray(),
        /*Final=*/false);
  if (Partial->isMemberSpecialization())
    return Response::Done();
} else {
  VarTemplateDecl *Tmpl = Specialized.get<VarTemplateDecl *>();
  if (!SkipForSpecialization)
    Result.addOuterTemplateArguments(
        Tmpl, VarTemplSpec->getTemplateInstantiationArgs().asArray(),
        /*Final=*/false);
  if (Tmpl->isMemberSpecialization())
    return Response::Done();
}
return Response::DontClearRelativeToPrimaryNextDecl(VarTemplSpec);
118}

120// If we have a template template parameter with translation unit context,
121// then we're performing substitution into a default template argument of
122// this template template parameter before we've constructed the template
123// that will own this template template parameter. In this case, we
124// use empty template parameter lists for all of the outer templates
125// to avoid performing any substitutions.
126Response
127HandleDefaultTempArgIntoTempTempParam(const TemplateTemplateParmDecl *TTP,
                                    MultiLevelTemplateArgumentList &Result) {
for (unsigned I = 0, N = TTP->getDepth() + 1; I != N; ++I)
  Result.addOuterTemplateArguments(std::nullopt);
return Response::Done();
132}

134// Add template arguments from a class template instantiation.
135Response
136HandleClassTemplateSpec(const ClassTemplateSpecializationDecl *ClassTemplSpec,
                      MultiLevelTemplateArgumentList &Result,
                      bool SkipForSpecialization) {
if (!ClassTemplSpec->isClassScopeExplicitSpecialization()) {
  // We're done when we hit an explicit specialization.
  if (ClassTemplSpec->getSpecializationKind() == TSK_ExplicitSpecialization &&
      !isa<ClassTemplatePartialSpecializationDecl>(ClassTemplSpec))
    return Response::Done();

  if (!SkipForSpecialization)
    Result.addOuterTemplateArguments(
        const_cast<ClassTemplateSpecializationDecl *>(ClassTemplSpec),
        ClassTemplSpec->getTemplateInstantiationArgs().asArray(),
        /*Final=*/false);

  // If this class template specialization was instantiated from a
  // specialized member that is a class template, we're done.
  assert(ClassTemplSpec->getSpecializedTemplate() && "No class template?")(static_cast <bool> (ClassTemplSpec->getSpecializedTemplate
() && "No class template?") ? void (0) : __assert_fail
 ("ClassTemplSpec->getSpecializedTemplate() && \"No class template?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 153, __extension__
 __PRETTY_FUNCTION__));
  if (ClassTemplSpec->getSpecializedTemplate()->isMemberSpecialization())
    return Response::Done();
}
return Response::UseNextDecl(ClassTemplSpec);
158}

160Response HandleFunction(const FunctionDecl *Function,
                      MultiLevelTemplateArgumentList &Result,
                      const FunctionDecl *Pattern, bool RelativeToPrimary,
                      bool ForConstraintInstantiation) {
// Add template arguments from a function template specialization.
if (!RelativeToPrimary &&
    Function->getTemplateSpecializationKindForInstantiation() ==
        TSK_ExplicitSpecialization)
  return Response::Done();

if (!RelativeToPrimary &&
    Function->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) {
  // This is an implicit instantiation of an explicit specialization. We
  // don't get any template arguments from this function but might get
  // some from an enclosing template.
  return Response::UseNextDecl(Function);
} else if (const TemplateArgumentList *TemplateArgs =
               Function->getTemplateSpecializationArgs()) {
  // Add the template arguments for this specialization.
  Result.addOuterTemplateArguments(const_cast<FunctionDecl *>(Function),
                                   TemplateArgs->asArray(),
                                   /*Final=*/false);

  // If this function was instantiated from a specialized member that is
  // a function template, we're done.
  assert(Function->getPrimaryTemplate() && "No function template?")(static_cast <bool> (Function->getPrimaryTemplate() &&
 "No function template?") ? void (0) : __assert_fail ("Function->getPrimaryTemplate() && \"No function template?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 185, __extension__
 __PRETTY_FUNCTION__));
  if (Function->getPrimaryTemplate()->isMemberSpecialization())
    return Response::Done();

  // If this function is a generic lambda specialization, we are done.
  if (!ForConstraintInstantiation &&
      isGenericLambdaCallOperatorOrStaticInvokerSpecialization(Function))
    return Response::Done();

} else if (Function->getDescribedFunctionTemplate()) {
  assert((static_cast <bool> ((ForConstraintInstantiation || Result
.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"
) ? void (0) : __assert_fail ("(ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) && \"Outer template not instantiated?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 197, __extension__
 __PRETTY_FUNCTION__))
      (ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) &&(static_cast <bool> ((ForConstraintInstantiation || Result
.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"
) ? void (0) : __assert_fail ("(ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) && \"Outer template not instantiated?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 197, __extension__
 __PRETTY_FUNCTION__))
      "Outer template not instantiated?")(static_cast <bool> ((ForConstraintInstantiation || Result
.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"
) ? void (0) : __assert_fail ("(ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) && \"Outer template not instantiated?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 197, __extension__
 __PRETTY_FUNCTION__));
}
// If this is a friend or local declaration and it declares an entity at
// namespace scope, take arguments from its lexical parent
// instead of its semantic parent, unless of course the pattern we're
// instantiating actually comes from the file's context!
if ((Function->getFriendObjectKind() || Function->isLocalExternDecl()) &&
    Function->getNonTransparentDeclContext()->isFileContext() &&
    (!Pattern || !Pattern->getLexicalDeclContext()->isFileContext())) {
  return Response::ChangeDecl(Function->getLexicalDeclContext());
}
return Response::UseNextDecl(Function);
209}

211Response HandleRecordDecl(const CXXRecordDecl *Rec,
                        MultiLevelTemplateArgumentList &Result,
                        ASTContext &Context,
                        bool ForConstraintInstantiation) {
if (ClassTemplateDecl *ClassTemplate = Rec->getDescribedClassTemplate()) {
  assert((static_cast <bool> ((ForConstraintInstantiation || Result
.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"
) ? void (0) : __assert_fail ("(ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) && \"Outer template not instantiated?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 218, __extension__
 __PRETTY_FUNCTION__))
      (ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) &&(static_cast <bool> ((ForConstraintInstantiation || Result
.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"
) ? void (0) : __assert_fail ("(ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) && \"Outer template not instantiated?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 218, __extension__
 __PRETTY_FUNCTION__))
      "Outer template not instantiated?")(static_cast <bool> ((ForConstraintInstantiation || Result
.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"
) ? void (0) : __assert_fail ("(ForConstraintInstantiation || Result.getNumSubstitutedLevels() == 0) && \"Outer template not instantiated?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 218, __extension__
 __PRETTY_FUNCTION__));
  if (ClassTemplate->isMemberSpecialization())
    return Response::Done();
  if (ForConstraintInstantiation) {
    QualType RecordType = Context.getTypeDeclType(Rec);
    QualType Injected = cast<InjectedClassNameType>(RecordType)
                            ->getInjectedSpecializationType();
    const auto *InjectedType = cast<TemplateSpecializationType>(Injected);
    Result.addOuterTemplateArguments(const_cast<CXXRecordDecl *>(Rec),
                                     InjectedType->template_arguments(),
                                     /*Final=*/false);
  }
}

bool IsFriend = Rec->getFriendObjectKind() ||
                (Rec->getDescribedClassTemplate() &&
                 Rec->getDescribedClassTemplate()->getFriendObjectKind());
if (ForConstraintInstantiation && IsFriend &&
    Rec->getNonTransparentDeclContext()->isFileContext()) {
  return Response::ChangeDecl(Rec->getLexicalDeclContext());
}

// This is to make sure we pick up the VarTemplateSpecializationDecl that this
// lambda is defined inside of.
if (Rec->isLambda())
  if (const Decl *LCD = Rec->getLambdaContextDecl())
    return Response::ChangeDecl(LCD);

return Response::UseNextDecl(Rec);
247}

249Response HandleImplicitConceptSpecializationDecl(
  const ImplicitConceptSpecializationDecl *CSD,
  MultiLevelTemplateArgumentList &Result) {
Result.addOuterTemplateArguments(
    const_cast<ImplicitConceptSpecializationDecl *>(CSD),
    CSD->getTemplateArguments(),
    /*Final=*/false);
return Response::UseNextDecl(CSD);
257}

259Response HandleGenericDeclContext(const Decl *CurDecl) {
return Response::UseNextDecl(CurDecl);
261}
262} // namespace TemplateInstArgsHelpers
263} // namespace

265/// Retrieve the template argument list(s) that should be used to
266/// instantiate the definition of the given declaration.
267///
268/// \param ND the declaration for which we are computing template instantiation
269/// arguments.
270///
271/// \param Innermost if non-NULL, specifies a template argument list for the
272/// template declaration passed as ND.
273///
274/// \param RelativeToPrimary true if we should get the template
275/// arguments relative to the primary template, even when we're
276/// dealing with a specialization. This is only relevant for function
277/// template specializations.
278///
279/// \param Pattern If non-NULL, indicates the pattern from which we will be
280/// instantiating the definition of the given declaration, \p ND. This is
281/// used to determine the proper set of template instantiation arguments for
282/// friend function template specializations.
283///
284/// \param ForConstraintInstantiation when collecting arguments,
285/// ForConstraintInstantiation indicates we should continue looking when
286/// encountering a lambda generic call operator, and continue looking for
287/// arguments on an enclosing class template.

289MultiLevelTemplateArgumentList Sema::getTemplateInstantiationArgs(
  const NamedDecl *ND, bool Final, const TemplateArgumentList *Innermost,
  bool RelativeToPrimary, const FunctionDecl *Pattern,
  bool ForConstraintInstantiation, bool SkipForSpecialization) {
assert(ND && "Can't find arguments for a decl if one isn't provided")(static_cast <bool> (ND && "Can't find arguments for a decl if one isn't provided"
) ? void (0) : __assert_fail ("ND && \"Can't find arguments for a decl if one isn't provided\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 293, __extension__
 __PRETTY_FUNCTION__));
// Accumulate the set of template argument lists in this structure.
MultiLevelTemplateArgumentList Result;

if (Innermost)
  Result.addOuterTemplateArguments(const_cast<NamedDecl *>(ND),
                                   Innermost->asArray(), Final);

const Decl *CurDecl = ND;

while (!CurDecl->isFileContextDecl()) {
  using namespace TemplateInstArgsHelpers;
  Response R;
  if (const auto *VarTemplSpec =
          dyn_cast<VarTemplateSpecializationDecl>(CurDecl)) {
    R = HandleVarTemplateSpec(VarTemplSpec, Result, SkipForSpecialization);
  } else if (const auto *ClassTemplSpec =
                 dyn_cast<ClassTemplateSpecializationDecl>(CurDecl)) {
    R = HandleClassTemplateSpec(ClassTemplSpec, Result,
                                SkipForSpecialization);
  } else if (const auto *Function = dyn_cast<FunctionDecl>(CurDecl)) {
    R = HandleFunction(Function, Result, Pattern, RelativeToPrimary,
                       ForConstraintInstantiation);
  } else if (const auto *Rec = dyn_cast<CXXRecordDecl>(CurDecl)) {
    R = HandleRecordDecl(Rec, Result, Context, ForConstraintInstantiation);
  } else if (const auto *CSD =
                 dyn_cast<ImplicitConceptSpecializationDecl>(CurDecl)) {
    R = HandleImplicitConceptSpecializationDecl(CSD, Result);
  } else if (!isa<DeclContext>(CurDecl)) {
    R = Response::DontClearRelativeToPrimaryNextDecl(CurDecl);
    if (CurDecl->getDeclContext()->isTranslationUnit()) {
      if (const auto *TTP = dyn_cast<TemplateTemplateParmDecl>(CurDecl)) {
        R = HandleDefaultTempArgIntoTempTempParam(TTP, Result);
      }
    }
  } else {
    R = HandleGenericDeclContext(CurDecl);
  }

  if (R.IsDone)
    return Result;
  if (R.ClearRelativeToPrimary)
    RelativeToPrimary = false;
  assert(R.NextDecl)(static_cast <bool> (R.NextDecl) ? void (0) : __assert_fail
 ("R.NextDecl", "clang/lib/Sema/SemaTemplateInstantiate.cpp",
 336, __extension__ __PRETTY_FUNCTION__));
  CurDecl = R.NextDecl;
}

return Result;
341}

343bool Sema::CodeSynthesisContext::isInstantiationRecord() const {
switch (Kind) {
case TemplateInstantiation:
case ExceptionSpecInstantiation:
case DefaultTemplateArgumentInstantiation:
case DefaultFunctionArgumentInstantiation:
case ExplicitTemplateArgumentSubstitution:
case DeducedTemplateArgumentSubstitution:
case PriorTemplateArgumentSubstitution:
case ConstraintsCheck:
case NestedRequirementConstraintsCheck:
  return true;

case RequirementInstantiation:
case RequirementParameterInstantiation:
case DefaultTemplateArgumentChecking:
case DeclaringSpecialMember:
case DeclaringImplicitEqualityComparison:
case DefiningSynthesizedFunction:
case ExceptionSpecEvaluation:
case ConstraintSubstitution:
case ParameterMappingSubstitution:
case ConstraintNormalization:
case RewritingOperatorAsSpaceship:
case InitializingStructuredBinding:
case MarkingClassDllexported:
case BuildingBuiltinDumpStructCall:
  return false;

// This function should never be called when Kind's value is Memoization.
case Memoization:
  break;
}

llvm_unreachable("Invalid SynthesisKind!")::llvm::llvm_unreachable_internal("Invalid SynthesisKind!", "clang/lib/Sema/SemaTemplateInstantiate.cpp"
, 377);
378}

380Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, CodeSynthesisContext::SynthesisKind Kind,
  SourceLocation PointOfInstantiation, SourceRange InstantiationRange,
  Decl *Entity, NamedDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
  sema::TemplateDeductionInfo *DeductionInfo)
  : SemaRef(SemaRef) {
// Don't allow further instantiation if a fatal error and an uncompilable
// error have occurred. Any diagnostics we might have raised will not be
// visible, and we do not need to construct a correct AST.
if (SemaRef.Diags.hasFatalErrorOccurred() &&
    SemaRef.hasUncompilableErrorOccurred()) {
  Invalid = true;
  return;
}
Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
if (!Invalid) {
  CodeSynthesisContext Inst;
  Inst.Kind = Kind;
  Inst.PointOfInstantiation = PointOfInstantiation;
  Inst.Entity = Entity;
  Inst.Template = Template;
  Inst.TemplateArgs = TemplateArgs.data();
  Inst.NumTemplateArgs = TemplateArgs.size();
  Inst.DeductionInfo = DeductionInfo;
  Inst.InstantiationRange = InstantiationRange;
  SemaRef.pushCodeSynthesisContext(Inst);

  AlreadyInstantiating = !Inst.Entity ? false :
      !SemaRef.InstantiatingSpecializations
           .insert({Inst.Entity->getCanonicalDecl(), Inst.Kind})
           .second;
  atTemplateBegin(SemaRef.TemplateInstCallbacks, SemaRef, Inst);
}
413}

415Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, Decl *Entity,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(SemaRef,
                          CodeSynthesisContext::TemplateInstantiation,
                          PointOfInstantiation, InstantiationRange, Entity) {}

422Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, FunctionDecl *Entity,
  ExceptionSpecification, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::ExceptionSpecInstantiation,
        PointOfInstantiation, InstantiationRange, Entity) {}

429Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateParameter Param,
  TemplateDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef,
        CodeSynthesisContext::DefaultTemplateArgumentInstantiation,
        PointOfInstantiation, InstantiationRange, getAsNamedDecl(Param),
        Template, TemplateArgs) {}

439Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  FunctionTemplateDecl *FunctionTemplate,
  ArrayRef<TemplateArgument> TemplateArgs,
  CodeSynthesisContext::SynthesisKind Kind,
  sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
  : InstantiatingTemplate(SemaRef, Kind, PointOfInstantiation,
                          InstantiationRange, FunctionTemplate, nullptr,
                          TemplateArgs, &DeductionInfo) {
assert((static_cast <bool> (Kind == CodeSynthesisContext::ExplicitTemplateArgumentSubstitution
 || Kind == CodeSynthesisContext::DeducedTemplateArgumentSubstitution
) ? void (0) : __assert_fail ("Kind == CodeSynthesisContext::ExplicitTemplateArgumentSubstitution || Kind == CodeSynthesisContext::DeducedTemplateArgumentSubstitution"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 450, __extension__
 __PRETTY_FUNCTION__))
  Kind == CodeSynthesisContext::ExplicitTemplateArgumentSubstitution ||(static_cast <bool> (Kind == CodeSynthesisContext::ExplicitTemplateArgumentSubstitution
 || Kind == CodeSynthesisContext::DeducedTemplateArgumentSubstitution
) ? void (0) : __assert_fail ("Kind == CodeSynthesisContext::ExplicitTemplateArgumentSubstitution || Kind == CodeSynthesisContext::DeducedTemplateArgumentSubstitution"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 450, __extension__
 __PRETTY_FUNCTION__))
  Kind == CodeSynthesisContext::DeducedTemplateArgumentSubstitution)(static_cast <bool> (Kind == CodeSynthesisContext::ExplicitTemplateArgumentSubstitution
 || Kind == CodeSynthesisContext::DeducedTemplateArgumentSubstitution
) ? void (0) : __assert_fail ("Kind == CodeSynthesisContext::ExplicitTemplateArgumentSubstitution || Kind == CodeSynthesisContext::DeducedTemplateArgumentSubstitution"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 450, __extension__
 __PRETTY_FUNCTION__));
451}

453Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  TemplateDecl *Template,
  ArrayRef<TemplateArgument> TemplateArgs,
  sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef,
        CodeSynthesisContext::DeducedTemplateArgumentSubstitution,
        PointOfInstantiation, InstantiationRange, Template, nullptr,
        TemplateArgs, &DeductionInfo) {}

464Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  ClassTemplatePartialSpecializationDecl *PartialSpec,
  ArrayRef<TemplateArgument> TemplateArgs,
  sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef,
        CodeSynthesisContext::DeducedTemplateArgumentSubstitution,
        PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
        TemplateArgs, &DeductionInfo) {}

475Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  VarTemplatePartialSpecializationDecl *PartialSpec,
  ArrayRef<TemplateArgument> TemplateArgs,
  sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef,
        CodeSynthesisContext::DeducedTemplateArgumentSubstitution,
        PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
        TemplateArgs, &DeductionInfo) {}

486Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, ParmVarDecl *Param,
  ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef,
        CodeSynthesisContext::DefaultFunctionArgumentInstantiation,
        PointOfInstantiation, InstantiationRange, Param, nullptr,
        TemplateArgs) {}

495Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
  NonTypeTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef,
        CodeSynthesisContext::PriorTemplateArgumentSubstitution,
        PointOfInstantiation, InstantiationRange, Param, Template,
        TemplateArgs) {}

505Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
  TemplateTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef,
        CodeSynthesisContext::PriorTemplateArgumentSubstitution,
        PointOfInstantiation, InstantiationRange, Param, Template,
        TemplateArgs) {}

515Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateDecl *Template,
  NamedDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::DefaultTemplateArgumentChecking,
        PointOfInstantiation, InstantiationRange, Param, Template,
        TemplateArgs) {}

524Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  concepts::Requirement *Req, sema::TemplateDeductionInfo &DeductionInfo,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::RequirementInstantiation,
        PointOfInstantiation, InstantiationRange, /*Entity=*/nullptr,
        /*Template=*/nullptr, /*TemplateArgs=*/std::nullopt, &DeductionInfo) {
532}

534Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  concepts::NestedRequirement *Req, ConstraintsCheck,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::NestedRequirementConstraintsCheck,
        PointOfInstantiation, InstantiationRange, /*Entity=*/nullptr,
        /*Template=*/nullptr, /*TemplateArgs=*/std::nullopt) {}

543Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation, const RequiresExpr *RE,
  sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::RequirementParameterInstantiation,
        PointOfInstantiation, InstantiationRange, /*Entity=*/nullptr,
        /*Template=*/nullptr, /*TemplateArgs=*/std::nullopt, &DeductionInfo) {
550}

552Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  ConstraintsCheck, NamedDecl *Template,
  ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::ConstraintsCheck,
        PointOfInstantiation, InstantiationRange, Template, nullptr,
        TemplateArgs) {}

561Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  ConstraintSubstitution, NamedDecl *Template,
  sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::ConstraintSubstitution,
        PointOfInstantiation, InstantiationRange, Template, nullptr,
        {}, &DeductionInfo) {}

570Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  ConstraintNormalization, NamedDecl *Template,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::ConstraintNormalization,
        PointOfInstantiation, InstantiationRange, Template) {}

578Sema::InstantiatingTemplate::InstantiatingTemplate(
  Sema &SemaRef, SourceLocation PointOfInstantiation,
  ParameterMappingSubstitution, NamedDecl *Template,
  SourceRange InstantiationRange)
  : InstantiatingTemplate(
        SemaRef, CodeSynthesisContext::ParameterMappingSubstitution,
        PointOfInstantiation, InstantiationRange, Template) {}


587void Sema::pushCodeSynthesisContext(CodeSynthesisContext Ctx) {
Ctx.SavedInNonInstantiationSFINAEContext = InNonInstantiationSFINAEContext;
InNonInstantiationSFINAEContext = false;

CodeSynthesisContexts.push_back(Ctx);

if (!Ctx.isInstantiationRecord())
  ++NonInstantiationEntries;

// Check to see if we're low on stack space. We can't do anything about this
// from here, but we can at least warn the user.
if (isStackNearlyExhausted())
  warnStackExhausted(Ctx.PointOfInstantiation);
600}

602void Sema::popCodeSynthesisContext() {
auto &Active = CodeSynthesisContexts.back();
if (!Active.isInstantiationRecord()) {
  assert(NonInstantiationEntries > 0)(static_cast <bool> (NonInstantiationEntries > 0) ? void
 (0) : __assert_fail ("NonInstantiationEntries > 0", "clang/lib/Sema/SemaTemplateInstantiate.cpp"
, 605, __extension__ __PRETTY_FUNCTION__));
  --NonInstantiationEntries;
}

InNonInstantiationSFINAEContext = Active.SavedInNonInstantiationSFINAEContext;

// Name lookup no longer looks in this template's defining module.
assert(CodeSynthesisContexts.size() >=(static_cast <bool> (CodeSynthesisContexts.size() >=
 CodeSynthesisContextLookupModules.size() && "forgot to remove a lookup module for a template instantiation"
) ? void (0) : __assert_fail ("CodeSynthesisContexts.size() >= CodeSynthesisContextLookupModules.size() && \"forgot to remove a lookup module for a template instantiation\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 614, __extension__
 __PRETTY_FUNCTION__))
           CodeSynthesisContextLookupModules.size() &&(static_cast <bool> (CodeSynthesisContexts.size() >=
 CodeSynthesisContextLookupModules.size() && "forgot to remove a lookup module for a template instantiation"
) ? void (0) : __assert_fail ("CodeSynthesisContexts.size() >= CodeSynthesisContextLookupModules.size() && \"forgot to remove a lookup module for a template instantiation\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 614, __extension__
 __PRETTY_FUNCTION__))
       "forgot to remove a lookup module for a template instantiation")(static_cast <bool> (CodeSynthesisContexts.size() >=
 CodeSynthesisContextLookupModules.size() && "forgot to remove a lookup module for a template instantiation"
) ? void (0) : __assert_fail ("CodeSynthesisContexts.size() >= CodeSynthesisContextLookupModules.size() && \"forgot to remove a lookup module for a template instantiation\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 614, __extension__
 __PRETTY_FUNCTION__));
if (CodeSynthesisContexts.size() ==
    CodeSynthesisContextLookupModules.size()) {
  if (Module *M = CodeSynthesisContextLookupModules.back())
    LookupModulesCache.erase(M);
  CodeSynthesisContextLookupModules.pop_back();
}

// If we've left the code synthesis context for the current context stack,
// stop remembering that we've emitted that stack.
if (CodeSynthesisContexts.size() ==
    LastEmittedCodeSynthesisContextDepth)
  LastEmittedCodeSynthesisContextDepth = 0;

CodeSynthesisContexts.pop_back();
629}

631void Sema::InstantiatingTemplate::Clear() {
if (!Invalid) {
  if (!AlreadyInstantiating) {
    auto &Active = SemaRef.CodeSynthesisContexts.back();
    if (Active.Entity)
      SemaRef.InstantiatingSpecializations.erase(
          {Active.Entity->getCanonicalDecl(), Active.Kind});
  }

  atTemplateEnd(SemaRef.TemplateInstCallbacks, SemaRef,
                SemaRef.CodeSynthesisContexts.back());

  SemaRef.popCodeSynthesisContext();
  Invalid = true;
}
646}

648static std::string convertCallArgsToString(Sema &S,
                                         llvm::ArrayRef<const Expr *> Args) {
std::string Result;
llvm::raw_string_ostream OS(Result);
llvm::ListSeparator Comma;
for (const Expr *Arg : Args) {
  OS << Comma;
  Arg->IgnoreParens()->printPretty(OS, nullptr,
                                   S.Context.getPrintingPolicy());
}
return Result;
659}

661bool Sema::InstantiatingTemplate::CheckInstantiationDepth(
                                      SourceLocation PointOfInstantiation,
                                         SourceRange InstantiationRange) {
assert(SemaRef.NonInstantiationEntries <=(static_cast <bool> (SemaRef.NonInstantiationEntries <=
 SemaRef.CodeSynthesisContexts.size()) ? void (0) : __assert_fail
 ("SemaRef.NonInstantiationEntries <= SemaRef.CodeSynthesisContexts.size()"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 665, __extension__
 __PRETTY_FUNCTION__))
       SemaRef.CodeSynthesisContexts.size())(static_cast <bool> (SemaRef.NonInstantiationEntries <=
 SemaRef.CodeSynthesisContexts.size()) ? void (0) : __assert_fail
 ("SemaRef.NonInstantiationEntries <= SemaRef.CodeSynthesisContexts.size()"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 665, __extension__
 __PRETTY_FUNCTION__));
if ((SemaRef.CodeSynthesisContexts.size() -
        SemaRef.NonInstantiationEntries)
      <= SemaRef.getLangOpts().InstantiationDepth)
  return false;

SemaRef.Diag(PointOfInstantiation,
             diag::err_template_recursion_depth_exceeded)
  << SemaRef.getLangOpts().InstantiationDepth
  << InstantiationRange;
SemaRef.Diag(PointOfInstantiation, diag::note_template_recursion_depth)
  << SemaRef.getLangOpts().InstantiationDepth;
return true;
678}

680/// Prints the current instantiation stack through a series of
681/// notes.
682void Sema::PrintInstantiationStack() {
// Determine which template instantiations to skip, if any.
unsigned SkipStart = CodeSynthesisContexts.size(), SkipEnd = SkipStart;
unsigned Limit = Diags.getTemplateBacktraceLimit();
if (Limit && Limit < CodeSynthesisContexts.size()) {
  SkipStart = Limit / 2 + Limit % 2;
  SkipEnd = CodeSynthesisContexts.size() - Limit / 2;
}

// FIXME: In all of these cases, we need to show the template arguments
unsigned InstantiationIdx = 0;
for (SmallVectorImpl<CodeSynthesisContext>::reverse_iterator
       Active = CodeSynthesisContexts.rbegin(),
       ActiveEnd = CodeSynthesisContexts.rend();
     Active != ActiveEnd;
     ++Active, ++InstantiationIdx) {
  // Skip this instantiation?
  if (InstantiationIdx >= SkipStart && InstantiationIdx < SkipEnd) {
    if (InstantiationIdx == SkipStart) {
      // Note that we're skipping instantiations.
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_instantiation_contexts_suppressed)
        << unsigned(CodeSynthesisContexts.size() - Limit);
    }
    continue;
  }

  switch (Active->Kind) {
  case CodeSynthesisContext::TemplateInstantiation: {
    Decl *D = Active->Entity;
    if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
      unsigned DiagID = diag::note_template_member_class_here;
      if (isa<ClassTemplateSpecializationDecl>(Record))
        DiagID = diag::note_template_class_instantiation_here;
      Diags.Report(Active->PointOfInstantiation, DiagID)
        << Record << Active->InstantiationRange;
    } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
      unsigned DiagID;
      if (Function->getPrimaryTemplate())
        DiagID = diag::note_function_template_spec_here;
      else
        DiagID = diag::note_template_member_function_here;
      Diags.Report(Active->PointOfInstantiation, DiagID)
        << Function
        << Active->InstantiationRange;
    } else if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
      Diags.Report(Active->PointOfInstantiation,
                   VD->isStaticDataMember()?
                     diag::note_template_static_data_member_def_here
                   : diag::note_template_variable_def_here)
        << VD
        << Active->InstantiationRange;
    } else if (EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_template_enum_def_here)
        << ED
        << Active->InstantiationRange;
    } else if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_template_nsdmi_here)
          << FD << Active->InstantiationRange;
    } else {
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_template_type_alias_instantiation_here)
        << cast<TypeAliasTemplateDecl>(D)
        << Active->InstantiationRange;
    }
    break;
  }

  case CodeSynthesisContext::DefaultTemplateArgumentInstantiation: {
    TemplateDecl *Template = cast<TemplateDecl>(Active->Template);
    SmallString<128> TemplateArgsStr;
    llvm::raw_svector_ostream OS(TemplateArgsStr);
    Template->printName(OS, getPrintingPolicy());
    printTemplateArgumentList(OS, Active->template_arguments(),
                              getPrintingPolicy());
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_default_arg_instantiation_here)
      << OS.str()
      << Active->InstantiationRange;
    break;
  }

  case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution: {
    FunctionTemplateDecl *FnTmpl = cast<FunctionTemplateDecl>(Active->Entity);
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_explicit_template_arg_substitution_here)
      << FnTmpl
      << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
                                         Active->TemplateArgs,
                                         Active->NumTemplateArgs)
      << Active->InstantiationRange;
    break;
  }

  case CodeSynthesisContext::DeducedTemplateArgumentSubstitution: {
    if (FunctionTemplateDecl *FnTmpl =
            dyn_cast<FunctionTemplateDecl>(Active->Entity)) {
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_function_template_deduction_instantiation_here)
        << FnTmpl
        << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
                                           Active->TemplateArgs,
                                           Active->NumTemplateArgs)
        << Active->InstantiationRange;
    } else {
      bool IsVar = isa<VarTemplateDecl>(Active->Entity) ||
                   isa<VarTemplateSpecializationDecl>(Active->Entity);
      bool IsTemplate = false;
      TemplateParameterList *Params;
      if (auto *D = dyn_cast<TemplateDecl>(Active->Entity)) {
        IsTemplate = true;
        Params = D->getTemplateParameters();
      } else if (auto *D = dyn_cast<ClassTemplatePartialSpecializationDecl>(
                     Active->Entity)) {
        Params = D->getTemplateParameters();
      } else if (auto *D = dyn_cast<VarTemplatePartialSpecializationDecl>(
                     Active->Entity)) {
        Params = D->getTemplateParameters();
      } else {
        llvm_unreachable("unexpected template kind")::llvm::llvm_unreachable_internal("unexpected template kind",
 "clang/lib/Sema/SemaTemplateInstantiate.cpp", 803);
      }

      Diags.Report(Active->PointOfInstantiation,
                   diag::note_deduced_template_arg_substitution_here)
        << IsVar << IsTemplate << cast<NamedDecl>(Active->Entity)
        << getTemplateArgumentBindingsText(Params, Active->TemplateArgs,
                                           Active->NumTemplateArgs)
        << Active->InstantiationRange;
    }
    break;
  }

  case CodeSynthesisContext::DefaultFunctionArgumentInstantiation: {
    ParmVarDecl *Param = cast<ParmVarDecl>(Active->Entity);
    FunctionDecl *FD = cast<FunctionDecl>(Param->getDeclContext());

    SmallString<128> TemplateArgsStr;
    llvm::raw_svector_ostream OS(TemplateArgsStr);
    FD->printName(OS, getPrintingPolicy());
    printTemplateArgumentList(OS, Active->template_arguments(),
                              getPrintingPolicy());
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_default_function_arg_instantiation_here)
      << OS.str()
      << Active->InstantiationRange;
    break;
  }

  case CodeSynthesisContext::PriorTemplateArgumentSubstitution: {
    NamedDecl *Parm = cast<NamedDecl>(Active->Entity);
    std::string Name;
    if (!Parm->getName().empty())
      Name = std::string(" '") + Parm->getName().str() + "'";

    TemplateParameterList *TemplateParams = nullptr;
    if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
      TemplateParams = Template->getTemplateParameters();
    else
      TemplateParams =
        cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
                                                    ->getTemplateParameters();
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_prior_template_arg_substitution)
      << isa<TemplateTemplateParmDecl>(Parm)
      << Name
      << getTemplateArgumentBindingsText(TemplateParams,
                                         Active->TemplateArgs,
                                         Active->NumTemplateArgs)
      << Active->InstantiationRange;
    break;
  }

  case CodeSynthesisContext::DefaultTemplateArgumentChecking: {
    TemplateParameterList *TemplateParams = nullptr;
    if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
      TemplateParams = Template->getTemplateParameters();
    else
      TemplateParams =
        cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
                                                    ->getTemplateParameters();

    Diags.Report(Active->PointOfInstantiation,
                 diag::note_template_default_arg_checking)
      << getTemplateArgumentBindingsText(TemplateParams,
                                         Active->TemplateArgs,
                                         Active->NumTemplateArgs)
      << Active->InstantiationRange;
    break;
  }

  case CodeSynthesisContext::ExceptionSpecEvaluation:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_evaluating_exception_spec_here)
        << cast<FunctionDecl>(Active->Entity);
    break;

  case CodeSynthesisContext::ExceptionSpecInstantiation:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_template_exception_spec_instantiation_here)
      << cast<FunctionDecl>(Active->Entity)
      << Active->InstantiationRange;
    break;

  case CodeSynthesisContext::RequirementInstantiation:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_template_requirement_instantiation_here)
      << Active->InstantiationRange;
    break;
  case CodeSynthesisContext::RequirementParameterInstantiation:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_template_requirement_params_instantiation_here)
        << Active->InstantiationRange;
    break;

  case CodeSynthesisContext::NestedRequirementConstraintsCheck:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_nested_requirement_here)
      << Active->InstantiationRange;
    break;

  case CodeSynthesisContext::DeclaringSpecialMember:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_in_declaration_of_implicit_special_member)
      << cast<CXXRecordDecl>(Active->Entity) << Active->SpecialMember;
    break;

  case CodeSynthesisContext::DeclaringImplicitEqualityComparison:
    Diags.Report(Active->Entity->getLocation(),
                 diag::note_in_declaration_of_implicit_equality_comparison);
    break;

  case CodeSynthesisContext::DefiningSynthesizedFunction: {
    // FIXME: For synthesized functions that are not defaulted,
    // produce a note.
    auto *FD = dyn_cast<FunctionDecl>(Active->Entity);
    DefaultedFunctionKind DFK =
        FD ? getDefaultedFunctionKind(FD) : DefaultedFunctionKind();
    if (DFK.isSpecialMember()) {
      auto *MD = cast<CXXMethodDecl>(FD);
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_member_synthesized_at)
          << MD->isExplicitlyDefaulted() << DFK.asSpecialMember()
          << Context.getTagDeclType(MD->getParent());
    } else if (DFK.isComparison()) {
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_comparison_synthesized_at)
          << (int)DFK.asComparison()
          << Context.getTagDeclType(
                 cast<CXXRecordDecl>(FD->getLexicalDeclContext()));
    }
    break;
  }

  case CodeSynthesisContext::RewritingOperatorAsSpaceship:
    Diags.Report(Active->Entity->getLocation(),
                 diag::note_rewriting_operator_as_spaceship);
    break;

  case CodeSynthesisContext::InitializingStructuredBinding:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_in_binding_decl_init)
        << cast<BindingDecl>(Active->Entity);
    break;

  case CodeSynthesisContext::MarkingClassDllexported:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_due_to_dllexported_class)
        << cast<CXXRecordDecl>(Active->Entity) << !getLangOpts().CPlusPlus11;
    break;

  case CodeSynthesisContext::BuildingBuiltinDumpStructCall:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_building_builtin_dump_struct_call)
        << convertCallArgsToString(
               *this, llvm::ArrayRef(Active->CallArgs, Active->NumCallArgs));
    break;

  case CodeSynthesisContext::Memoization:
    break;

  case CodeSynthesisContext::ConstraintsCheck: {
    unsigned DiagID = 0;
    if (!Active->Entity) {
      Diags.Report(Active->PointOfInstantiation,
                   diag::note_nested_requirement_here)
        << Active->InstantiationRange;
      break;
    }
    if (isa<ConceptDecl>(Active->Entity))
      DiagID = diag::note_concept_specialization_here;
    else if (isa<TemplateDecl>(Active->Entity))
      DiagID = diag::note_checking_constraints_for_template_id_here;
    else if (isa<VarTemplatePartialSpecializationDecl>(Active->Entity))
      DiagID = diag::note_checking_constraints_for_var_spec_id_here;
    else if (isa<ClassTemplatePartialSpecializationDecl>(Active->Entity))
      DiagID = diag::note_checking_constraints_for_class_spec_id_here;
    else {
      assert(isa<FunctionDecl>(Active->Entity))(static_cast <bool> (isa<FunctionDecl>(Active->
Entity)) ? void (0) : __assert_fail ("isa<FunctionDecl>(Active->Entity)"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 981, __extension__
 __PRETTY_FUNCTION__));
      DiagID = diag::note_checking_constraints_for_function_here;
    }
    SmallString<128> TemplateArgsStr;
    llvm::raw_svector_ostream OS(TemplateArgsStr);
    cast<NamedDecl>(Active->Entity)->printName(OS, getPrintingPolicy());
    if (!isa<FunctionDecl>(Active->Entity)) {
      printTemplateArgumentList(OS, Active->template_arguments(),
                                getPrintingPolicy());
    }
    Diags.Report(Active->PointOfInstantiation, DiagID) << OS.str()
      << Active->InstantiationRange;
    break;
  }
  case CodeSynthesisContext::ConstraintSubstitution:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_constraint_substitution_here)
        << Active->InstantiationRange;
    break;
  case CodeSynthesisContext::ConstraintNormalization:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_constraint_normalization_here)
        << cast<NamedDecl>(Active->Entity)->getName()
        << Active->InstantiationRange;
    break;
  case CodeSynthesisContext::ParameterMappingSubstitution:
    Diags.Report(Active->PointOfInstantiation,
                 diag::note_parameter_mapping_substitution_here)
        << Active->InstantiationRange;
    break;
  }
}
1013}

1015std::optional<TemplateDeductionInfo *> Sema::isSFINAEContext() const {
if (InNonInstantiationSFINAEContext)
  return std::optional<TemplateDeductionInfo *>(nullptr);

for (SmallVectorImpl<CodeSynthesisContext>::const_reverse_iterator
       Active = CodeSynthesisContexts.rbegin(),
       ActiveEnd = CodeSynthesisContexts.rend();
     Active != ActiveEnd;
     ++Active)
{
  switch (Active->Kind) {
  case CodeSynthesisContext::TemplateInstantiation:
    // An instantiation of an alias template may or may not be a SFINAE
    // context, depending on what else is on the stack.
    if (isa<TypeAliasTemplateDecl>(Active->Entity))
      break;
    [[fallthrough]];
  case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
  case CodeSynthesisContext::ExceptionSpecInstantiation:
  case CodeSynthesisContext::ConstraintsCheck:
  case CodeSynthesisContext::ParameterMappingSubstitution:
  case CodeSynthesisContext::ConstraintNormalization:
  case CodeSynthesisContext::NestedRequirementConstraintsCheck:
    // This is a template instantiation, so there is no SFINAE.
    return std::nullopt;

  case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
  case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
  case CodeSynthesisContext::DefaultTemplateArgumentChecking:
  case CodeSynthesisContext::RewritingOperatorAsSpaceship:
    // A default template argument instantiation and substitution into
    // template parameters with arguments for prior parameters may or may
    // not be a SFINAE context; look further up the stack.
    break;

  case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
  case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
  case CodeSynthesisContext::ConstraintSubstitution:
  case CodeSynthesisContext::RequirementInstantiation:
  case CodeSynthesisContext::RequirementParameterInstantiation:
    // We're either substituting explicitly-specified template arguments,
    // deduced template arguments, a constraint expression or a requirement
    // in a requires expression, so SFINAE applies.
    assert(Active->DeductionInfo && "Missing deduction info pointer")(static_cast <bool> (Active->DeductionInfo &&
 "Missing deduction info pointer") ? void (0) : __assert_fail
 ("Active->DeductionInfo && \"Missing deduction info pointer\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1058, __extension__
 __PRETTY_FUNCTION__));
    return Active->DeductionInfo;

  case CodeSynthesisContext::DeclaringSpecialMember:
  case CodeSynthesisContext::DeclaringImplicitEqualityComparison:
  case CodeSynthesisContext::DefiningSynthesizedFunction:
  case CodeSynthesisContext::InitializingStructuredBinding:
  case CodeSynthesisContext::MarkingClassDllexported:
  case CodeSynthesisContext::BuildingBuiltinDumpStructCall:
    // This happens in a context unrelated to template instantiation, so
    // there is no SFINAE.
    return std::nullopt;

  case CodeSynthesisContext::ExceptionSpecEvaluation:
    // FIXME: This should not be treated as a SFINAE context, because
    // we will cache an incorrect exception specification. However, clang
    // bootstrap relies this! See PR31692.
    break;

  case CodeSynthesisContext::Memoization:
    break;
  }

  // The inner context was transparent for SFINAE. If it occurred within a
  // non-instantiation SFINAE context, then SFINAE applies.
  if (Active->SavedInNonInstantiationSFINAEContext)
    return std::optional<TemplateDeductionInfo *>(nullptr);
}

return std::nullopt;
1088}

1090//===----------------------------------------------------------------------===/
1091// Template Instantiation for Types
1092//===----------------------------------------------------------------------===/
1093namespace {
class TemplateInstantiator : public TreeTransform<TemplateInstantiator> {
  const MultiLevelTemplateArgumentList &TemplateArgs;
  SourceLocation Loc;
  DeclarationName Entity;
  bool EvaluateConstraints = true;

public:
  typedef TreeTransform<TemplateInstantiator> inherited;

  TemplateInstantiator(Sema &SemaRef,
                       const MultiLevelTemplateArgumentList &TemplateArgs,
                       SourceLocation Loc, DeclarationName Entity)
      : inherited(SemaRef), TemplateArgs(TemplateArgs), Loc(Loc),
        Entity(Entity) {}

  void setEvaluateConstraints(bool B) {
    EvaluateConstraints = B;
  }
  bool getEvaluateConstraints() {
    return EvaluateConstraints;
  }

  /// Determine whether the given type \p T has already been
  /// transformed.
  ///
  /// For the purposes of template instantiation, a type has already been
  /// transformed if it is NULL or if it is not dependent.
  bool AlreadyTransformed(QualType T);

  /// Returns the location of the entity being instantiated, if known.
  SourceLocation getBaseLocation() { return Loc; }

  /// Returns the name of the entity being instantiated, if any.
  DeclarationName getBaseEntity() { return Entity; }

  /// Sets the "base" location and entity when that
  /// information is known based on another transformation.
  void setBase(SourceLocation Loc, DeclarationName Entity) {
    this->Loc = Loc;
    this->Entity = Entity;
  }

  unsigned TransformTemplateDepth(unsigned Depth) {
    return TemplateArgs.getNewDepth(Depth);
  }

  std::optional<unsigned> getPackIndex(TemplateArgument Pack) {
    int Index = getSema().ArgumentPackSubstitutionIndex;
    if (Index == -1)
      return std::nullopt;
    return Pack.pack_size() - 1 - Index;
  }

  bool TryExpandParameterPacks(SourceLocation EllipsisLoc,
                               SourceRange PatternRange,
                               ArrayRef<UnexpandedParameterPack> Unexpanded,
                               bool &ShouldExpand, bool &RetainExpansion,
                               std::optional<unsigned> &NumExpansions) {
    return getSema().CheckParameterPacksForExpansion(EllipsisLoc,
                                                     PatternRange, Unexpanded,
                                                     TemplateArgs,
                                                     ShouldExpand,
                                                     RetainExpansion,
                                                     NumExpansions);
  }

  void ExpandingFunctionParameterPack(ParmVarDecl *Pack) {
    SemaRef.CurrentInstantiationScope->MakeInstantiatedLocalArgPack(Pack);
  }

  TemplateArgument ForgetPartiallySubstitutedPack() {
    TemplateArgument Result;
    if (NamedDecl *PartialPack
          = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
      MultiLevelTemplateArgumentList &TemplateArgs
        = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
      unsigned Depth, Index;
      std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
      if (TemplateArgs.hasTemplateArgument(Depth, Index)) {
        Result = TemplateArgs(Depth, Index);
        TemplateArgs.setArgument(Depth, Index, TemplateArgument());
      }
    }

    return Result;
  }

  void RememberPartiallySubstitutedPack(TemplateArgument Arg) {
    if (Arg.isNull())
      return;

    if (NamedDecl *PartialPack
          = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
      MultiLevelTemplateArgumentList &TemplateArgs
      = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
      unsigned Depth, Index;
      std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
      TemplateArgs.setArgument(Depth, Index, Arg);
    }
  }

  /// Transform the given declaration by instantiating a reference to
  /// this declaration.
  Decl *TransformDecl(SourceLocation Loc, Decl *D);

  void transformAttrs(Decl *Old, Decl *New) {
    SemaRef.InstantiateAttrs(TemplateArgs, Old, New);
  }

  void transformedLocalDecl(Decl *Old, ArrayRef<Decl *> NewDecls) {
    if (Old->isParameterPack()) {
17
←
Assuming the condition is false→
      SemaRef.CurrentInstantiationScope->MakeInstantiatedLocalArgPack(Old);
      for (auto *New : NewDecls)
        SemaRef.CurrentInstantiationScope->InstantiatedLocalPackArg(
            Old, cast<VarDecl>(New));
      return;
    }

    assert(NewDecls.size() == 1 &&(static_cast <bool> (NewDecls.size() == 1 && "should only have multiple expansions for a pack"
) ? void (0) : __assert_fail ("NewDecls.size() == 1 && \"should only have multiple expansions for a pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1213, __extension__
 __PRETTY_FUNCTION__))
18
←
Taking false branch→
19
←
Assuming the condition is true→
20
←
'?' condition is true→
           "should only have multiple expansions for a pack")(static_cast <bool> (NewDecls.size() == 1 && "should only have multiple expansions for a pack"
) ? void (0) : __assert_fail ("NewDecls.size() == 1 && \"should only have multiple expansions for a pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1213, __extension__
 __PRETTY_FUNCTION__));
    Decl *New = NewDecls.front();

    // If we've instantiated the call operator of a lambda or the call
    // operator template of a generic lambda, update the "instantiation of"
    // information.
    auto *NewMD = dyn_cast<CXXMethodDecl>(New);
21
←
Assuming 'New' is a 'CastReturnType'→
    if (NewMD21.1
'NewMD' is non-null
1
'NewMD' is non-null
 && isLambdaCallOperator(NewMD)) {
22
←
Taking true branch→
      auto *OldMD = dyn_cast<CXXMethodDecl>(Old);
23
←
Assuming 'Old' is not a 'CastReturnType'→
24
←
'OldMD' initialized to a null pointer value→
      if (auto *NewTD = NewMD->getDescribedFunctionTemplate())
25
←
Assuming 'NewTD' is non-null→
26
←
Taking true branch→
        NewTD->setInstantiatedFromMemberTemplate(
            OldMD->getDescribedFunctionTemplate());
27
←
Called C++ object pointer is null
      else
        NewMD->setInstantiationOfMemberFunction(OldMD,
                                                TSK_ImplicitInstantiation);
    }

    SemaRef.CurrentInstantiationScope->InstantiatedLocal(Old, New);

    // We recreated a local declaration, but not by instantiating it. There
    // may be pending dependent diagnostics to produce.
    if (auto *DC = dyn_cast<DeclContext>(Old);
        DC && DC->isDependentContext() && DC->isFunctionOrMethod())
      SemaRef.PerformDependentDiagnostics(DC, TemplateArgs);
  }

  /// Transform the definition of the given declaration by
  /// instantiating it.
  Decl *TransformDefinition(SourceLocation Loc, Decl *D);

  /// Transform the first qualifier within a scope by instantiating the
  /// declaration.
  NamedDecl *TransformFirstQualifierInScope(NamedDecl *D, SourceLocation Loc);

  /// Rebuild the exception declaration and register the declaration
  /// as an instantiated local.
  VarDecl *RebuildExceptionDecl(VarDecl *ExceptionDecl,
                                TypeSourceInfo *Declarator,
                                SourceLocation StartLoc,
                                SourceLocation NameLoc,
                                IdentifierInfo *Name);

  /// Rebuild the Objective-C exception declaration and register the
  /// declaration as an instantiated local.
  VarDecl *RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
                                    TypeSourceInfo *TSInfo, QualType T);

  /// Check for tag mismatches when instantiating an
  /// elaborated type.
  QualType RebuildElaboratedType(SourceLocation KeywordLoc,
                                 ElaboratedTypeKeyword Keyword,
                                 NestedNameSpecifierLoc QualifierLoc,
                                 QualType T);

  TemplateName
  TransformTemplateName(CXXScopeSpec &SS, TemplateName Name,
                        SourceLocation NameLoc,
                        QualType ObjectType = QualType(),
                        NamedDecl *FirstQualifierInScope = nullptr,
                        bool AllowInjectedClassName = false);

  const LoopHintAttr *TransformLoopHintAttr(const LoopHintAttr *LH);
  const NoInlineAttr *TransformStmtNoInlineAttr(const Stmt *OrigS,
                                                const Stmt *InstS,
                                                const NoInlineAttr *A);
  const AlwaysInlineAttr *
  TransformStmtAlwaysInlineAttr(const Stmt *OrigS, const Stmt *InstS,
                                const AlwaysInlineAttr *A);

  ExprResult TransformPredefinedExpr(PredefinedExpr *E);
  ExprResult TransformDeclRefExpr(DeclRefExpr *E);
  ExprResult TransformCXXDefaultArgExpr(CXXDefaultArgExpr *E);

  ExprResult TransformTemplateParmRefExpr(DeclRefExpr *E,
                                          NonTypeTemplateParmDecl *D);
  ExprResult TransformSubstNonTypeTemplateParmPackExpr(
                                         SubstNonTypeTemplateParmPackExpr *E);
  ExprResult TransformSubstNonTypeTemplateParmExpr(
                                         SubstNonTypeTemplateParmExpr *E);

  /// Rebuild a DeclRefExpr for a VarDecl reference.
  ExprResult RebuildVarDeclRefExpr(VarDecl *PD, SourceLocation Loc);

  /// Transform a reference to a function or init-capture parameter pack.
  ExprResult TransformFunctionParmPackRefExpr(DeclRefExpr *E, VarDecl *PD);

  /// Transform a FunctionParmPackExpr which was built when we couldn't
  /// expand a function parameter pack reference which refers to an expanded
  /// pack.
  ExprResult TransformFunctionParmPackExpr(FunctionParmPackExpr *E);

  QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
                                      FunctionProtoTypeLoc TL) {
    // Call the base version; it will forward to our overridden version below.
    return inherited::TransformFunctionProtoType(TLB, TL);
  }

  template<typename Fn>
  QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
                                      FunctionProtoTypeLoc TL,
                                      CXXRecordDecl *ThisContext,
                                      Qualifiers ThisTypeQuals,
                                      Fn TransformExceptionSpec);

  ParmVarDecl *
  TransformFunctionTypeParam(ParmVarDecl *OldParm, int indexAdjustment,
                             std::optional<unsigned> NumExpansions,
                             bool ExpectParameterPack);

  using inherited::TransformTemplateTypeParmType;
  /// Transforms a template type parameter type by performing
  /// substitution of the corresponding template type argument.
  QualType TransformTemplateTypeParmType(TypeLocBuilder &TLB,
                                         TemplateTypeParmTypeLoc TL,
                                         bool SuppressObjCLifetime);

  QualType BuildSubstTemplateTypeParmType(
      TypeLocBuilder &TLB, bool SuppressObjCLifetime, bool Final,
      Decl *AssociatedDecl, unsigned Index, std::optional<unsigned> PackIndex,
      TemplateArgument Arg, SourceLocation NameLoc);

  /// Transforms an already-substituted template type parameter pack
  /// into either itself (if we aren't substituting into its pack expansion)
  /// or the appropriate substituted argument.
  using inherited::TransformSubstTemplateTypeParmPackType;
  QualType
  TransformSubstTemplateTypeParmPackType(TypeLocBuilder &TLB,
                                         SubstTemplateTypeParmPackTypeLoc TL,
                                         bool SuppressObjCLifetime);

  ExprResult TransformLambdaExpr(LambdaExpr *E) {
    LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
    Sema::ConstraintEvalRAII<TemplateInstantiator> RAII(*this);
    ExprResult Result = inherited::TransformLambdaExpr(E);
1
Calling 'TreeTransform::TransformLambdaExpr'→
    if (Result.isInvalid())
      return Result;

    CXXMethodDecl *MD = Result.getAs<LambdaExpr>()->getCallOperator();
    for (ParmVarDecl *PVD : MD->parameters()) {
      if (!PVD || !PVD->hasDefaultArg())
        continue;
      Expr *UninstExpr = PVD->getUninstantiatedDefaultArg();
      // FIXME: Obtain the source location for the '=' token.
      SourceLocation EqualLoc = UninstExpr->getBeginLoc();
      if (SemaRef.SubstDefaultArgument(EqualLoc, PVD, TemplateArgs)) {
        // If substitution fails, the default argument is set to a
        // RecoveryExpr that wraps the uninstantiated default argument so
        // that downstream diagnostics are omitted.
        ExprResult ErrorResult = SemaRef.CreateRecoveryExpr(
            UninstExpr->getBeginLoc(), UninstExpr->getEndLoc(),
            { UninstExpr }, UninstExpr->getType());
        if (ErrorResult.isUsable())
          PVD->setDefaultArg(ErrorResult.get());
      }
    }

    return Result;
  }

  ExprResult TransformRequiresExpr(RequiresExpr *E) {
    LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
    ExprResult TransReq = inherited::TransformRequiresExpr(E);
    if (TransReq.isInvalid())
      return TransReq;
    assert(TransReq.get() != E &&(static_cast <bool> (TransReq.get() != E && "Do not change value of isSatisfied for the existing expression. "
 "Create a new expression instead.") ? void (0) : __assert_fail
 ("TransReq.get() != E && \"Do not change value of isSatisfied for the existing expression. \" \"Create a new expression instead.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1379, __extension__
 __PRETTY_FUNCTION__))
           "Do not change value of isSatisfied for the existing expression. "(static_cast <bool> (TransReq.get() != E && "Do not change value of isSatisfied for the existing expression. "
 "Create a new expression instead.") ? void (0) : __assert_fail
 ("TransReq.get() != E && \"Do not change value of isSatisfied for the existing expression. \" \"Create a new expression instead.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1379, __extension__
 __PRETTY_FUNCTION__))
           "Create a new expression instead.")(static_cast <bool> (TransReq.get() != E && "Do not change value of isSatisfied for the existing expression. "
 "Create a new expression instead.") ? void (0) : __assert_fail
 ("TransReq.get() != E && \"Do not change value of isSatisfied for the existing expression. \" \"Create a new expression instead.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1379, __extension__
 __PRETTY_FUNCTION__));
    if (E->getBody()->isDependentContext()) {
      Sema::SFINAETrap Trap(SemaRef);
      // We recreate the RequiresExpr body, but not by instantiating it.
      // Produce pending diagnostics for dependent access check.
      SemaRef.PerformDependentDiagnostics(E->getBody(), TemplateArgs);
      // FIXME: Store SFINAE diagnostics in RequiresExpr for diagnosis.
      if (Trap.hasErrorOccurred())
        TransReq.getAs<RequiresExpr>()->setSatisfied(false);
    }
    return TransReq;
  }

  bool TransformRequiresExprRequirements(
      ArrayRef<concepts::Requirement *> Reqs,
      SmallVectorImpl<concepts::Requirement *> &Transformed) {
    bool SatisfactionDetermined = false;
    for (concepts::Requirement *Req : Reqs) {
      concepts::Requirement *TransReq = nullptr;
      if (!SatisfactionDetermined) {
        if (auto *TypeReq = dyn_cast<concepts::TypeRequirement>(Req))
          TransReq = TransformTypeRequirement(TypeReq);
        else if (auto *ExprReq = dyn_cast<concepts::ExprRequirement>(Req))
          TransReq = TransformExprRequirement(ExprReq);
        else
          TransReq = TransformNestedRequirement(
              cast<concepts::NestedRequirement>(Req));
        if (!TransReq)
          return true;
        if (!TransReq->isDependent() && !TransReq->isSatisfied())
          // [expr.prim.req]p6
          //   [...]  The substitution and semantic constraint checking
          //   proceeds in lexical order and stops when a condition that
          //   determines the result of the requires-expression is
          //   encountered. [..]
          SatisfactionDetermined = true;
      } else
        TransReq = Req;
      Transformed.push_back(TransReq);
    }
    return false;
  }

  TemplateParameterList *TransformTemplateParameterList(
                            TemplateParameterList *OrigTPL)  {
    if (!OrigTPL || !OrigTPL->size()) return OrigTPL;

    DeclContext *Owner = OrigTPL->getParam(0)->getDeclContext();
    TemplateDeclInstantiator  DeclInstantiator(getSema(),
                      /* DeclContext *Owner */ Owner, TemplateArgs);
    DeclInstantiator.setEvaluateConstraints(EvaluateConstraints);
    return DeclInstantiator.SubstTemplateParams(OrigTPL);
  }

  concepts::TypeRequirement *
  TransformTypeRequirement(concepts::TypeRequirement *Req);
  concepts::ExprRequirement *
  TransformExprRequirement(concepts::ExprRequirement *Req);
  concepts::NestedRequirement *
  TransformNestedRequirement(concepts::NestedRequirement *Req);
  ExprResult TransformRequiresTypeParams(
      SourceLocation KWLoc, SourceLocation RBraceLoc, const RequiresExpr *RE,
      RequiresExprBodyDecl *Body, ArrayRef<ParmVarDecl *> Params,
      SmallVectorImpl<QualType> &PTypes,
      SmallVectorImpl<ParmVarDecl *> &TransParams,
      Sema::ExtParameterInfoBuilder &PInfos);

private:
  ExprResult
  transformNonTypeTemplateParmRef(Decl *AssociatedDecl,
                                  const NonTypeTemplateParmDecl *parm,
                                  SourceLocation loc, TemplateArgument arg,
                                  std::optional<unsigned> PackIndex);
};
1453}

1455bool TemplateInstantiator::AlreadyTransformed(QualType T) {
if (T.isNull())
  return true;

if (T->isInstantiationDependentType() || T->isVariablyModifiedType())
  return false;

getSema().MarkDeclarationsReferencedInType(Loc, T);
return true;
1464}

1466static TemplateArgument
1467getPackSubstitutedTemplateArgument(Sema &S, TemplateArgument Arg) {
assert(S.ArgumentPackSubstitutionIndex >= 0)(static_cast <bool> (S.ArgumentPackSubstitutionIndex >=
 0) ? void (0) : __assert_fail ("S.ArgumentPackSubstitutionIndex >= 0"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1468, __extension__
 __PRETTY_FUNCTION__));
assert(S.ArgumentPackSubstitutionIndex < (int)Arg.pack_size())(static_cast <bool> (S.ArgumentPackSubstitutionIndex <
 (int)Arg.pack_size()) ? void (0) : __assert_fail ("S.ArgumentPackSubstitutionIndex < (int)Arg.pack_size()"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1469, __extension__
 __PRETTY_FUNCTION__));
Arg = Arg.pack_begin()[S.ArgumentPackSubstitutionIndex];
if (Arg.isPackExpansion())
  Arg = Arg.getPackExpansionPattern();
return Arg;
1474}

1476Decl *TemplateInstantiator::TransformDecl(SourceLocation Loc, Decl *D) {
if (!D)
  return nullptr;

if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(D)) {
  if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
    // If the corresponding template argument is NULL or non-existent, it's
    // because we are performing instantiation from explicitly-specified
    // template arguments in a function template, but there were some
    // arguments left unspecified.
    if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
                                          TTP->getPosition()))
      return D;

    TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());

    if (TTP->isParameterPack()) {
      assert(Arg.getKind() == TemplateArgument::Pack &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1494, __extension__
 __PRETTY_FUNCTION__))
             "Missing argument pack")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1494, __extension__
 __PRETTY_FUNCTION__));
      Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
    }

    TemplateName Template = Arg.getAsTemplate().getNameToSubstitute();
    assert(!Template.isNull() && Template.getAsTemplateDecl() &&(static_cast <bool> (!Template.isNull() && Template
.getAsTemplateDecl() && "Wrong kind of template template argument"
) ? void (0) : __assert_fail ("!Template.isNull() && Template.getAsTemplateDecl() && \"Wrong kind of template template argument\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1500, __extension__
 __PRETTY_FUNCTION__))
           "Wrong kind of template template argument")(static_cast <bool> (!Template.isNull() && Template
.getAsTemplateDecl() && "Wrong kind of template template argument"
) ? void (0) : __assert_fail ("!Template.isNull() && Template.getAsTemplateDecl() && \"Wrong kind of template template argument\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1500, __extension__
 __PRETTY_FUNCTION__));
    return Template.getAsTemplateDecl();
  }

  // Fall through to find the instantiated declaration for this template
  // template parameter.
}

return SemaRef.FindInstantiatedDecl(Loc, cast<NamedDecl>(D), TemplateArgs);
1509}

1511Decl *TemplateInstantiator::TransformDefinition(SourceLocation Loc, Decl *D) {
Decl *Inst = getSema().SubstDecl(D, getSema().CurContext, TemplateArgs);
if (!Inst)
  return nullptr;

getSema().CurrentInstantiationScope->InstantiatedLocal(D, Inst);
return Inst;
1518}

1520NamedDecl *
1521TemplateInstantiator::TransformFirstQualifierInScope(NamedDecl *D,
                                                   SourceLocation Loc) {
// If the first part of the nested-name-specifier was a template type
// parameter, instantiate that type parameter down to a tag type.
if (TemplateTypeParmDecl *TTPD = dyn_cast_or_null<TemplateTypeParmDecl>(D)) {
  const TemplateTypeParmType *TTP
    = cast<TemplateTypeParmType>(getSema().Context.getTypeDeclType(TTPD));

  if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
    // FIXME: This needs testing w/ member access expressions.
    TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getIndex());

    if (TTP->isParameterPack()) {
      assert(Arg.getKind() == TemplateArgument::Pack &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1535, __extension__
 __PRETTY_FUNCTION__))
             "Missing argument pack")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1535, __extension__
 __PRETTY_FUNCTION__));

      if (getSema().ArgumentPackSubstitutionIndex == -1)
        return nullptr;

      Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
    }

    QualType T = Arg.getAsType();
    if (T.isNull())
      return cast_or_null<NamedDecl>(TransformDecl(Loc, D));

    if (const TagType *Tag = T->getAs<TagType>())
      return Tag->getDecl();

    // The resulting type is not a tag; complain.
    getSema().Diag(Loc, diag::err_nested_name_spec_non_tag) << T;
    return nullptr;
  }
}

return cast_or_null<NamedDecl>(TransformDecl(Loc, D));
1557}

1559VarDecl *
1560TemplateInstantiator::RebuildExceptionDecl(VarDecl *ExceptionDecl,
                                         TypeSourceInfo *Declarator,
                                         SourceLocation StartLoc,
                                         SourceLocation NameLoc,
                                         IdentifierInfo *Name) {
VarDecl *Var = inherited::RebuildExceptionDecl(ExceptionDecl, Declarator,
                                               StartLoc, NameLoc, Name);
if (Var)
  getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
return Var;
1570}

1572VarDecl *TemplateInstantiator::RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
                                                      TypeSourceInfo *TSInfo,
                                                      QualType T) {
VarDecl *Var = inherited::RebuildObjCExceptionDecl(ExceptionDecl, TSInfo, T);
if (Var)
  getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
return Var;
1579}

1581QualType
1582TemplateInstantiator::RebuildElaboratedType(SourceLocation KeywordLoc,
                                          ElaboratedTypeKeyword Keyword,
                                          NestedNameSpecifierLoc QualifierLoc,
                                          QualType T) {
if (const TagType *TT = T->getAs<TagType>()) {
  TagDecl* TD = TT->getDecl();

  SourceLocation TagLocation = KeywordLoc;

  IdentifierInfo *Id = TD->getIdentifier();

  // TODO: should we even warn on struct/class mismatches for this?  Seems
  // like it's likely to produce a lot of spurious errors.
  if (Id && Keyword != ETK_None && Keyword != ETK_Typename) {
    TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForKeyword(Keyword);
    if (!SemaRef.isAcceptableTagRedeclaration(TD, Kind, /*isDefinition*/false,
                                              TagLocation, Id)) {
      SemaRef.Diag(TagLocation, diag::err_use_with_wrong_tag)
        << Id
        << FixItHint::CreateReplacement(SourceRange(TagLocation),
                                        TD->getKindName());
      SemaRef.Diag(TD->getLocation(), diag::note_previous_use);
    }
  }
}

return inherited::RebuildElaboratedType(KeywordLoc, Keyword, QualifierLoc, T);
1609}

1611TemplateName TemplateInstantiator::TransformTemplateName(
  CXXScopeSpec &SS, TemplateName Name, SourceLocation NameLoc,
  QualType ObjectType, NamedDecl *FirstQualifierInScope,
  bool AllowInjectedClassName) {
if (TemplateTemplateParmDecl *TTP
     = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())) {
  if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
    // If the corresponding template argument is NULL or non-existent, it's
    // because we are performing instantiation from explicitly-specified
    // template arguments in a function template, but there were some
    // arguments left unspecified.
    if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
                                          TTP->getPosition()))
      return Name;

    TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());

    if (TemplateArgs.isRewrite()) {
      // We're rewriting the template parameter as a reference to another
      // template parameter.
      if (Arg.getKind() == TemplateArgument::Pack) {
        assert(Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() &&(static_cast <bool> (Arg.pack_size() == 1 && Arg
.pack_begin()->isPackExpansion() && "unexpected pack arguments in template rewrite"
) ? void (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() && \"unexpected pack arguments in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1633, __extension__
 __PRETTY_FUNCTION__))
               "unexpected pack arguments in template rewrite")(static_cast <bool> (Arg.pack_size() == 1 && Arg
.pack_begin()->isPackExpansion() && "unexpected pack arguments in template rewrite"
) ? void (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() && \"unexpected pack arguments in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1633, __extension__
 __PRETTY_FUNCTION__));
        Arg = Arg.pack_begin()->getPackExpansionPattern();
      }
      assert(Arg.getKind() == TemplateArgument::Template &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Template && "unexpected nontype template argument kind in template rewrite"
) ? void (0) : __assert_fail ("Arg.getKind() == TemplateArgument::Template && \"unexpected nontype template argument kind in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1637, __extension__
 __PRETTY_FUNCTION__))
             "unexpected nontype template argument kind in template rewrite")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Template && "unexpected nontype template argument kind in template rewrite"
) ? void (0) : __assert_fail ("Arg.getKind() == TemplateArgument::Template && \"unexpected nontype template argument kind in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1637, __extension__
 __PRETTY_FUNCTION__));
      return Arg.getAsTemplate();
    }

    auto [AssociatedDecl, Final] =
        TemplateArgs.getAssociatedDecl(TTP->getDepth());
    std::optional<unsigned> PackIndex;
    if (TTP->isParameterPack()) {
      assert(Arg.getKind() == TemplateArgument::Pack &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1646, __extension__
 __PRETTY_FUNCTION__))
             "Missing argument pack")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1646, __extension__
 __PRETTY_FUNCTION__));

      if (getSema().ArgumentPackSubstitutionIndex == -1) {
        // We have the template argument pack to substitute, but we're not
        // actually expanding the enclosing pack expansion yet. So, just
        // keep the entire argument pack.
        return getSema().Context.getSubstTemplateTemplateParmPack(
            Arg, AssociatedDecl, TTP->getIndex(), Final);
      }

      PackIndex = getPackIndex(Arg);
      Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
    }

    TemplateName Template = Arg.getAsTemplate().getNameToSubstitute();
    assert(!Template.isNull() && "Null template template argument")(static_cast <bool> (!Template.isNull() && "Null template template argument"
) ? void (0) : __assert_fail ("!Template.isNull() && \"Null template template argument\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1661, __extension__
 __PRETTY_FUNCTION__));
    assert(!Template.getAsQualifiedTemplateName() &&(static_cast <bool> (!Template.getAsQualifiedTemplateName
() && "template decl to substitute is qualified?") ? void
 (0) : __assert_fail ("!Template.getAsQualifiedTemplateName() && \"template decl to substitute is qualified?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1663, __extension__
 __PRETTY_FUNCTION__))
           "template decl to substitute is qualified?")(static_cast <bool> (!Template.getAsQualifiedTemplateName
() && "template decl to substitute is qualified?") ? void
 (0) : __assert_fail ("!Template.getAsQualifiedTemplateName() && \"template decl to substitute is qualified?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1663, __extension__
 __PRETTY_FUNCTION__));

    if (Final)
      return Template;
    return getSema().Context.getSubstTemplateTemplateParm(
        Template, AssociatedDecl, TTP->getIndex(), PackIndex);
  }
}

if (SubstTemplateTemplateParmPackStorage *SubstPack
    = Name.getAsSubstTemplateTemplateParmPack()) {
  if (getSema().ArgumentPackSubstitutionIndex == -1)
    return Name;

  TemplateArgument Pack = SubstPack->getArgumentPack();
  TemplateName Template =
      getPackSubstitutedTemplateArgument(getSema(), Pack).getAsTemplate();
  if (SubstPack->getFinal())
    return Template;
  return getSema().Context.getSubstTemplateTemplateParm(
      Template.getNameToSubstitute(), SubstPack->getAssociatedDecl(),
      SubstPack->getIndex(), getPackIndex(Pack));
}

return inherited::TransformTemplateName(SS, Name, NameLoc, ObjectType,
                                        FirstQualifierInScope,
                                        AllowInjectedClassName);
1690}

1692ExprResult
1693TemplateInstantiator::TransformPredefinedExpr(PredefinedExpr *E) {
if (!E->isTypeDependent())
  return E;

return getSema().BuildPredefinedExpr(E->getLocation(), E->getIdentKind());
1698}

1700ExprResult
1701TemplateInstantiator::TransformTemplateParmRefExpr(DeclRefExpr *E,
                                             NonTypeTemplateParmDecl *NTTP) {
// If the corresponding template argument is NULL or non-existent, it's
// because we are performing instantiation from explicitly-specified
// template arguments in a function template, but there were some
// arguments left unspecified.
if (!TemplateArgs.hasTemplateArgument(NTTP->getDepth(),
                                      NTTP->getPosition()))
  return E;

TemplateArgument Arg = TemplateArgs(NTTP->getDepth(), NTTP->getPosition());

if (TemplateArgs.isRewrite()) {
  // We're rewriting the template parameter as a reference to another
  // template parameter.
  if (Arg.getKind() == TemplateArgument::Pack) {
    assert(Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() &&(static_cast <bool> (Arg.pack_size() == 1 && Arg
.pack_begin()->isPackExpansion() && "unexpected pack arguments in template rewrite"
) ? void (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() && \"unexpected pack arguments in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1718, __extension__
 __PRETTY_FUNCTION__))
           "unexpected pack arguments in template rewrite")(static_cast <bool> (Arg.pack_size() == 1 && Arg
.pack_begin()->isPackExpansion() && "unexpected pack arguments in template rewrite"
) ? void (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() && \"unexpected pack arguments in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1718, __extension__
 __PRETTY_FUNCTION__));
    Arg = Arg.pack_begin()->getPackExpansionPattern();
  }
  assert(Arg.getKind() == TemplateArgument::Expression &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Expression && "unexpected nontype template argument kind in template rewrite"
) ? void (0) : __assert_fail ("Arg.getKind() == TemplateArgument::Expression && \"unexpected nontype template argument kind in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1722, __extension__
 __PRETTY_FUNCTION__))
         "unexpected nontype template argument kind in template rewrite")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Expression && "unexpected nontype template argument kind in template rewrite"
) ? void (0) : __assert_fail ("Arg.getKind() == TemplateArgument::Expression && \"unexpected nontype template argument kind in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1722, __extension__
 __PRETTY_FUNCTION__));
  // FIXME: This can lead to the same subexpression appearing multiple times
  // in a complete expression.
  return Arg.getAsExpr();
}

auto [AssociatedDecl, _] = TemplateArgs.getAssociatedDecl(NTTP->getDepth());
std::optional<unsigned> PackIndex;
if (NTTP->isParameterPack()) {
  assert(Arg.getKind() == TemplateArgument::Pack &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1732, __extension__
 __PRETTY_FUNCTION__))
         "Missing argument pack")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1732, __extension__
 __PRETTY_FUNCTION__));

  if (getSema().ArgumentPackSubstitutionIndex == -1) {
    // We have an argument pack, but we can't select a particular argument
    // out of it yet. Therefore, we'll build an expression to hold on to that
    // argument pack.
    QualType TargetType = SemaRef.SubstType(NTTP->getType(), TemplateArgs,
                                            E->getLocation(),
                                            NTTP->getDeclName());
    if (TargetType.isNull())
      return ExprError();

    QualType ExprType = TargetType.getNonLValueExprType(SemaRef.Context);
    if (TargetType->isRecordType())
      ExprType.addConst();
    // FIXME: Pass in Final.
    return new (SemaRef.Context) SubstNonTypeTemplateParmPackExpr(
        ExprType, TargetType->isReferenceType() ? VK_LValue : VK_PRValue,
        E->getLocation(), Arg, AssociatedDecl, NTTP->getPosition());
  }
  PackIndex = getPackIndex(Arg);
  Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
}
// FIXME: Don't put subst node on Final replacement.
return transformNonTypeTemplateParmRef(AssociatedDecl, NTTP, E->getLocation(),
                                       Arg, PackIndex);
1758}

1760const LoopHintAttr *
1761TemplateInstantiator::TransformLoopHintAttr(const LoopHintAttr *LH) {
Expr *TransformedExpr = getDerived().TransformExpr(LH->getValue()).get();

if (TransformedExpr == LH->getValue())
  return LH;

// Generate error if there is a problem with the value.
if (getSema().CheckLoopHintExpr(TransformedExpr, LH->getLocation()))
  return LH;

// Create new LoopHintValueAttr with integral expression in place of the
// non-type template parameter.
return LoopHintAttr::CreateImplicit(getSema().Context, LH->getOption(),
                                    LH->getState(), TransformedExpr, *LH);
1775}
1776const NoInlineAttr *TemplateInstantiator::TransformStmtNoInlineAttr(
  const Stmt *OrigS, const Stmt *InstS, const NoInlineAttr *A) {
if (!A || getSema().CheckNoInlineAttr(OrigS, InstS, *A))
  return nullptr;

return A;
1782}
1783const AlwaysInlineAttr *TemplateInstantiator::TransformStmtAlwaysInlineAttr(
  const Stmt *OrigS, const Stmt *InstS, const AlwaysInlineAttr *A) {
if (!A || getSema().CheckAlwaysInlineAttr(OrigS, InstS, *A))
  return nullptr;

return A;
1789}

1791ExprResult TemplateInstantiator::transformNonTypeTemplateParmRef(
  Decl *AssociatedDecl, const NonTypeTemplateParmDecl *parm,
  SourceLocation loc, TemplateArgument arg,
  std::optional<unsigned> PackIndex) {
ExprResult result;

// Determine the substituted parameter type. We can usually infer this from
// the template argument, but not always.
auto SubstParamType = [&] {
  QualType T;
  if (parm->isExpandedParameterPack())
    T = parm->getExpansionType(SemaRef.ArgumentPackSubstitutionIndex);
  else
    T = parm->getType();
  if (parm->isParameterPack() && isa<PackExpansionType>(T))
    T = cast<PackExpansionType>(T)->getPattern();
  return SemaRef.SubstType(T, TemplateArgs, loc, parm->getDeclName());
};

bool refParam = false;

// The template argument itself might be an expression, in which case we just
// return that expression. This happens when substituting into an alias
// template.
if (arg.getKind() == TemplateArgument::Expression) {
  Expr *argExpr = arg.getAsExpr();
  result = argExpr;
  if (argExpr->isLValue()) {
    if (argExpr->getType()->isRecordType()) {
      // Check whether the parameter was actually a reference.
      QualType paramType = SubstParamType();
      if (paramType.isNull())
        return ExprError();
      refParam = paramType->isReferenceType();
    } else {
      refParam = true;
    }
  }
} else if (arg.getKind() == TemplateArgument::Declaration ||
           arg.getKind() == TemplateArgument::NullPtr) {
  ValueDecl *VD;
  if (arg.getKind() == TemplateArgument::Declaration) {
    VD = arg.getAsDecl();

    // Find the instantiation of the template argument.  This is
    // required for nested templates.
    VD = cast_or_null<ValueDecl>(
           getSema().FindInstantiatedDecl(loc, VD, TemplateArgs));
    if (!VD)
      return ExprError();
  } else {
    // Propagate NULL template argument.
    VD = nullptr;
  }

  QualType paramType = VD ? arg.getParamTypeForDecl() : arg.getNullPtrType();
  assert(!paramType.isNull() && "type substitution failed for param type")(static_cast <bool> (!paramType.isNull() && "type substitution failed for param type"
) ? void (0) : __assert_fail ("!paramType.isNull() && \"type substitution failed for param type\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1847, __extension__
 __PRETTY_FUNCTION__));
  assert(!paramType->isDependentType() && "param type still dependent")(static_cast <bool> (!paramType->isDependentType() &&
 "param type still dependent") ? void (0) : __assert_fail ("!paramType->isDependentType() && \"param type still dependent\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1848, __extension__
 __PRETTY_FUNCTION__));
  result = SemaRef.BuildExpressionFromDeclTemplateArgument(arg, paramType, loc);
  refParam = paramType->isReferenceType();
} else {
  result = SemaRef.BuildExpressionFromIntegralTemplateArgument(arg, loc);
  assert(result.isInvalid() ||(static_cast <bool> (result.isInvalid() || SemaRef.Context
.hasSameType(result.get()->getType(), arg.getIntegralType(
))) ? void (0) : __assert_fail ("result.isInvalid() || SemaRef.Context.hasSameType(result.get()->getType(), arg.getIntegralType())"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1855, __extension__
 __PRETTY_FUNCTION__))
         SemaRef.Context.hasSameType(result.get()->getType(),(static_cast <bool> (result.isInvalid() || SemaRef.Context
.hasSameType(result.get()->getType(), arg.getIntegralType(
))) ? void (0) : __assert_fail ("result.isInvalid() || SemaRef.Context.hasSameType(result.get()->getType(), arg.getIntegralType())"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1855, __extension__
 __PRETTY_FUNCTION__))
                                     arg.getIntegralType()))(static_cast <bool> (result.isInvalid() || SemaRef.Context
.hasSameType(result.get()->getType(), arg.getIntegralType(
))) ? void (0) : __assert_fail ("result.isInvalid() || SemaRef.Context.hasSameType(result.get()->getType(), arg.getIntegralType())"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1855, __extension__
 __PRETTY_FUNCTION__));
}

if (result.isInvalid())
  return ExprError();

Expr *resultExpr = result.get();
// FIXME: Don't put subst node on final replacement.
return new (SemaRef.Context) SubstNonTypeTemplateParmExpr(
    resultExpr->getType(), resultExpr->getValueKind(), loc, resultExpr,
    AssociatedDecl, parm->getIndex(), PackIndex, refParam);
1866}

1868ExprResult
1869TemplateInstantiator::TransformSubstNonTypeTemplateParmPackExpr(
                                        SubstNonTypeTemplateParmPackExpr *E) {
if (getSema().ArgumentPackSubstitutionIndex == -1) {
  // We aren't expanding the parameter pack, so just return ourselves.
  return E;
}

TemplateArgument Pack = E->getArgumentPack();
TemplateArgument Arg = getPackSubstitutedTemplateArgument(getSema(), Pack);
// FIXME: Don't put subst node on final replacement.
return transformNonTypeTemplateParmRef(
    E->getAssociatedDecl(), E->getParameterPack(),
    E->getParameterPackLocation(), Arg, getPackIndex(Pack));
1882}

1884ExprResult
1885TemplateInstantiator::TransformSubstNonTypeTemplateParmExpr(
                                        SubstNonTypeTemplateParmExpr *E) {
ExprResult SubstReplacement = E->getReplacement();
if (!isa<ConstantExpr>(SubstReplacement.get()))
  SubstReplacement = TransformExpr(E->getReplacement());
if (SubstReplacement.isInvalid())
  return true;
QualType SubstType = TransformType(E->getParameterType(getSema().Context));
if (SubstType.isNull())
  return true;
// The type may have been previously dependent and not now, which means we
// might have to implicit cast the argument to the new type, for example:
// template<auto T, decltype(T) U>
// concept C = sizeof(U) == 4;
// void foo() requires C<2, 'a'> { }
// When normalizing foo(), we first form the normalized constraints of C:
// AtomicExpr(sizeof(U) == 4,
//            U=SubstNonTypeTemplateParmExpr(Param=U,
//                                           Expr=DeclRef(U),
//                                           Type=decltype(T)))
// Then we substitute T = 2, U = 'a' into the parameter mapping, and need to
// produce:
// AtomicExpr(sizeof(U) == 4,
//            U=SubstNonTypeTemplateParmExpr(Param=U,
//                                           Expr=ImpCast(
//                                               decltype(2),
//                                               SubstNTTPE(Param=U, Expr='a',
//                                                          Type=char)),
//                                           Type=decltype(2)))
// The call to CheckTemplateArgument here produces the ImpCast.
TemplateArgument SugaredConverted, CanonicalConverted;
if (SemaRef
        .CheckTemplateArgument(E->getParameter(), SubstType,
                               SubstReplacement.get(), SugaredConverted,
                               CanonicalConverted, Sema::CTAK_Specified)
        .isInvalid())
  return true;
return transformNonTypeTemplateParmRef(E->getAssociatedDecl(),
                                       E->getParameter(), E->getExprLoc(),
                                       SugaredConverted, E->getPackIndex());
1925}

1927ExprResult TemplateInstantiator::RebuildVarDeclRefExpr(VarDecl *PD,
                                                     SourceLocation Loc) {
DeclarationNameInfo NameInfo(PD->getDeclName(), Loc);
return getSema().BuildDeclarationNameExpr(CXXScopeSpec(), NameInfo, PD);
1931}

1933ExprResult
1934TemplateInstantiator::TransformFunctionParmPackExpr(FunctionParmPackExpr *E) {
if (getSema().ArgumentPackSubstitutionIndex != -1) {
  // We can expand this parameter pack now.
  VarDecl *D = E->getExpansion(getSema().ArgumentPackSubstitutionIndex);
  VarDecl *VD = cast_or_null<VarDecl>(TransformDecl(E->getExprLoc(), D));
  if (!VD)
    return ExprError();
  return RebuildVarDeclRefExpr(VD, E->getExprLoc());
}

QualType T = TransformType(E->getType());
if (T.isNull())
  return ExprError();

// Transform each of the parameter expansions into the corresponding
// parameters in the instantiation of the function decl.
SmallVector<VarDecl *, 8> Vars;
Vars.reserve(E->getNumExpansions());
for (FunctionParmPackExpr::iterator I = E->begin(), End = E->end();
     I != End; ++I) {
  VarDecl *D = cast_or_null<VarDecl>(TransformDecl(E->getExprLoc(), *I));
  if (!D)
    return ExprError();
  Vars.push_back(D);
}

auto *PackExpr =
    FunctionParmPackExpr::Create(getSema().Context, T, E->getParameterPack(),
                                 E->getParameterPackLocation(), Vars);
getSema().MarkFunctionParmPackReferenced(PackExpr);
return PackExpr;
1965}

1967ExprResult
1968TemplateInstantiator::TransformFunctionParmPackRefExpr(DeclRefExpr *E,
                                                     VarDecl *PD) {
typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
llvm::PointerUnion<Decl *, DeclArgumentPack *> *Found
  = getSema().CurrentInstantiationScope->findInstantiationOf(PD);
assert(Found && "no instantiation for parameter pack")(static_cast <bool> (Found && "no instantiation for parameter pack"
) ? void (0) : __assert_fail ("Found && \"no instantiation for parameter pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 1973, __extension__
 __PRETTY_FUNCTION__));

Decl *TransformedDecl;
if (DeclArgumentPack *Pack = Found->dyn_cast<DeclArgumentPack *>()) {
  // If this is a reference to a function parameter pack which we can
  // substitute but can't yet expand, build a FunctionParmPackExpr for it.
  if (getSema().ArgumentPackSubstitutionIndex == -1) {
    QualType T = TransformType(E->getType());
    if (T.isNull())
      return ExprError();
    auto *PackExpr = FunctionParmPackExpr::Create(getSema().Context, T, PD,
                                                  E->getExprLoc(), *Pack);
    getSema().MarkFunctionParmPackReferenced(PackExpr);
    return PackExpr;
  }

  TransformedDecl = (*Pack)[getSema().ArgumentPackSubstitutionIndex];
} else {
  TransformedDecl = Found->get<Decl*>();
}

// We have either an unexpanded pack or a specific expansion.
return RebuildVarDeclRefExpr(cast<VarDecl>(TransformedDecl), E->getExprLoc());
1996}

1998ExprResult
1999TemplateInstantiator::TransformDeclRefExpr(DeclRefExpr *E) {
NamedDecl *D = E->getDecl();

// Handle references to non-type template parameters and non-type template
// parameter packs.
if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D)) {
  if (NTTP->getDepth() < TemplateArgs.getNumLevels())
    return TransformTemplateParmRefExpr(E, NTTP);

  // We have a non-type template parameter that isn't fully substituted;
  // FindInstantiatedDecl will find it in the local instantiation scope.
}

// Handle references to function parameter packs.
if (VarDecl *PD = dyn_cast<VarDecl>(D))
  if (PD->isParameterPack())
    return TransformFunctionParmPackRefExpr(E, PD);

return inherited::TransformDeclRefExpr(E);
2018}

2020ExprResult TemplateInstantiator::TransformCXXDefaultArgExpr(
  CXXDefaultArgExpr *E) {
assert(!cast<FunctionDecl>(E->getParam()->getDeclContext())->(static_cast <bool> (!cast<FunctionDecl>(E->getParam
()->getDeclContext())-> getDescribedFunctionTemplate() &&
 "Default arg expressions are never formed in dependent cases."
) ? void (0) : __assert_fail ("!cast<FunctionDecl>(E->getParam()->getDeclContext())-> getDescribedFunctionTemplate() && \"Default arg expressions are never formed in dependent cases.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2024, __extension__
 __PRETTY_FUNCTION__))
           getDescribedFunctionTemplate() &&(static_cast <bool> (!cast<FunctionDecl>(E->getParam
()->getDeclContext())-> getDescribedFunctionTemplate() &&
 "Default arg expressions are never formed in dependent cases."
) ? void (0) : __assert_fail ("!cast<FunctionDecl>(E->getParam()->getDeclContext())-> getDescribedFunctionTemplate() && \"Default arg expressions are never formed in dependent cases.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2024, __extension__
 __PRETTY_FUNCTION__))
       "Default arg expressions are never formed in dependent cases.")(static_cast <bool> (!cast<FunctionDecl>(E->getParam
()->getDeclContext())-> getDescribedFunctionTemplate() &&
 "Default arg expressions are never formed in dependent cases."
) ? void (0) : __assert_fail ("!cast<FunctionDecl>(E->getParam()->getDeclContext())-> getDescribedFunctionTemplate() && \"Default arg expressions are never formed in dependent cases.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2024, __extension__
 __PRETTY_FUNCTION__));
return SemaRef.BuildCXXDefaultArgExpr(
    E->getUsedLocation(), cast<FunctionDecl>(E->getParam()->getDeclContext()),
    E->getParam());
2028}

2030template<typename Fn>
2031QualType TemplateInstantiator::TransformFunctionProtoType(TypeLocBuilder &TLB,
                               FunctionProtoTypeLoc TL,
                               CXXRecordDecl *ThisContext,
                               Qualifiers ThisTypeQuals,
                               Fn TransformExceptionSpec) {
// We need a local instantiation scope for this function prototype.
LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
return inherited::TransformFunctionProtoType(
    TLB, TL, ThisContext, ThisTypeQuals, TransformExceptionSpec);
2040}

2042ParmVarDecl *TemplateInstantiator::TransformFunctionTypeParam(
  ParmVarDecl *OldParm, int indexAdjustment,
  std::optional<unsigned> NumExpansions, bool ExpectParameterPack) {
auto NewParm = SemaRef.SubstParmVarDecl(
    OldParm, TemplateArgs, indexAdjustment, NumExpansions,
    ExpectParameterPack, EvaluateConstraints);
if (NewParm && SemaRef.getLangOpts().OpenCL)
  SemaRef.deduceOpenCLAddressSpace(NewParm);
return NewParm;
2051}

2053QualType TemplateInstantiator::BuildSubstTemplateTypeParmType(
  TypeLocBuilder &TLB, bool SuppressObjCLifetime, bool Final,
  Decl *AssociatedDecl, unsigned Index, std::optional<unsigned> PackIndex,
  TemplateArgument Arg, SourceLocation NameLoc) {
QualType Replacement = Arg.getAsType();

// If the template parameter had ObjC lifetime qualifiers,
// then any such qualifiers on the replacement type are ignored.
if (SuppressObjCLifetime) {
  Qualifiers RQs;
  RQs = Replacement.getQualifiers();
  RQs.removeObjCLifetime();
  Replacement =
      SemaRef.Context.getQualifiedType(Replacement.getUnqualifiedType(), RQs);
}

if (Final) {
  TLB.pushTrivial(SemaRef.Context, Replacement, NameLoc);
  return Replacement;
}
// TODO: only do this uniquing once, at the start of instantiation.
QualType Result = getSema().Context.getSubstTemplateTypeParmType(
    Replacement, AssociatedDecl, Index, PackIndex);
SubstTemplateTypeParmTypeLoc NewTL =
    TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
NewTL.setNameLoc(NameLoc);
return Result;
2080}

2082QualType
2083TemplateInstantiator::TransformTemplateTypeParmType(TypeLocBuilder &TLB,
                                                  TemplateTypeParmTypeLoc TL,
                                                  bool SuppressObjCLifetime) {
const TemplateTypeParmType *T = TL.getTypePtr();
if (T->getDepth() < TemplateArgs.getNumLevels()) {
  // Replace the template type parameter with its corresponding
  // template argument.

  // If the corresponding template argument is NULL or doesn't exist, it's
  // because we are performing instantiation from explicitly-specified
  // template arguments in a function template class, but there were some
  // arguments left unspecified.
  if (!TemplateArgs.hasTemplateArgument(T->getDepth(), T->getIndex())) {
    TemplateTypeParmTypeLoc NewTL
      = TLB.push<TemplateTypeParmTypeLoc>(TL.getType());
    NewTL.setNameLoc(TL.getNameLoc());
    return TL.getType();
  }

  TemplateArgument Arg = TemplateArgs(T->getDepth(), T->getIndex());

  if (TemplateArgs.isRewrite()) {
    // We're rewriting the template parameter as a reference to another
    // template parameter.
    if (Arg.getKind() == TemplateArgument::Pack) {
      assert(Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() &&(static_cast <bool> (Arg.pack_size() == 1 && Arg
.pack_begin()->isPackExpansion() && "unexpected pack arguments in template rewrite"
) ? void (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() && \"unexpected pack arguments in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2109, __extension__
 __PRETTY_FUNCTION__))
             "unexpected pack arguments in template rewrite")(static_cast <bool> (Arg.pack_size() == 1 && Arg
.pack_begin()->isPackExpansion() && "unexpected pack arguments in template rewrite"
) ? void (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion() && \"unexpected pack arguments in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2109, __extension__
 __PRETTY_FUNCTION__));
      Arg = Arg.pack_begin()->getPackExpansionPattern();
    }
    assert(Arg.getKind() == TemplateArgument::Type &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Type && "unexpected nontype template argument kind in template rewrite"
) ? void (0) : __assert_fail ("Arg.getKind() == TemplateArgument::Type && \"unexpected nontype template argument kind in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2113, __extension__
 __PRETTY_FUNCTION__))
           "unexpected nontype template argument kind in template rewrite")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Type && "unexpected nontype template argument kind in template rewrite"
) ? void (0) : __assert_fail ("Arg.getKind() == TemplateArgument::Type && \"unexpected nontype template argument kind in template rewrite\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2113, __extension__
 __PRETTY_FUNCTION__));
    QualType NewT = Arg.getAsType();
    assert(isa<TemplateTypeParmType>(NewT) &&(static_cast <bool> (isa<TemplateTypeParmType>(NewT
) && "type parm not rewritten to type parm") ? void (
0) : __assert_fail ("isa<TemplateTypeParmType>(NewT) && \"type parm not rewritten to type parm\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2116, __extension__
 __PRETTY_FUNCTION__))
           "type parm not rewritten to type parm")(static_cast <bool> (isa<TemplateTypeParmType>(NewT
) && "type parm not rewritten to type parm") ? void (
0) : __assert_fail ("isa<TemplateTypeParmType>(NewT) && \"type parm not rewritten to type parm\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2116, __extension__
 __PRETTY_FUNCTION__));
    auto NewTL = TLB.push<TemplateTypeParmTypeLoc>(NewT);
    NewTL.setNameLoc(TL.getNameLoc());
    return NewT;
  }

  auto [AssociatedDecl, Final] =
      TemplateArgs.getAssociatedDecl(T->getDepth());
  std::optional<unsigned> PackIndex;
  if (T->isParameterPack()) {
    assert(Arg.getKind() == TemplateArgument::Pack &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2127, __extension__
 __PRETTY_FUNCTION__))
           "Missing argument pack")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Pack && "Missing argument pack") ? void (0) : __assert_fail
 ("Arg.getKind() == TemplateArgument::Pack && \"Missing argument pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2127, __extension__
 __PRETTY_FUNCTION__));

    if (getSema().ArgumentPackSubstitutionIndex == -1) {
      // We have the template argument pack, but we're not expanding the
      // enclosing pack expansion yet. Just save the template argument
      // pack for later substitution.
      QualType Result = getSema().Context.getSubstTemplateTypeParmPackType(
          AssociatedDecl, T->getIndex(), Final, Arg);
      SubstTemplateTypeParmPackTypeLoc NewTL
        = TLB.push<SubstTemplateTypeParmPackTypeLoc>(Result);
      NewTL.setNameLoc(TL.getNameLoc());
      return Result;
    }

    // PackIndex starts from last element.
    PackIndex = getPackIndex(Arg);
    Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
  }

  assert(Arg.getKind() == TemplateArgument::Type &&(static_cast <bool> (Arg.getKind() == TemplateArgument::
Type && "Template argument kind mismatch") ? void (0)
 : __assert_fail ("Arg.getKind() == TemplateArgument::Type && \"Template argument kind mismatch\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2147, __extension__
 __PRETTY_FUNCTION__))
         "Template argument kind mismatch")(static_cast <bool> (Arg.getKind() == TemplateArgument::
Type && "Template argument kind mismatch") ? void (0)
 : __assert_fail ("Arg.getKind() == TemplateArgument::Type && \"Template argument kind mismatch\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2147, __extension__
 __PRETTY_FUNCTION__));

  return BuildSubstTemplateTypeParmType(TLB, SuppressObjCLifetime, Final,
                                        AssociatedDecl, T->getIndex(),
                                        PackIndex, Arg, TL.getNameLoc());
}

// The template type parameter comes from an inner template (e.g.,
// the template parameter list of a member template inside the
// template we are instantiating). Create a new template type
// parameter with the template "level" reduced by one.
TemplateTypeParmDecl *NewTTPDecl = nullptr;
if (TemplateTypeParmDecl *OldTTPDecl = T->getDecl())
  NewTTPDecl = cast_or_null<TemplateTypeParmDecl>(
      TransformDecl(TL.getNameLoc(), OldTTPDecl));
QualType Result = getSema().Context.getTemplateTypeParmType(
    T->getDepth() - TemplateArgs.getNumSubstitutedLevels(), T->getIndex(),
    T->isParameterPack(), NewTTPDecl);
TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result);
NewTL.setNameLoc(TL.getNameLoc());
return Result;
2168}

2170QualType TemplateInstantiator::TransformSubstTemplateTypeParmPackType(
  TypeLocBuilder &TLB, SubstTemplateTypeParmPackTypeLoc TL,
  bool SuppressObjCLifetime) {
const SubstTemplateTypeParmPackType *T = TL.getTypePtr();

Decl *NewReplaced = TransformDecl(TL.getNameLoc(), T->getAssociatedDecl());

if (getSema().ArgumentPackSubstitutionIndex == -1) {
  // We aren't expanding the parameter pack, so just return ourselves.
  QualType Result = TL.getType();
  if (NewReplaced != T->getAssociatedDecl())
    Result = getSema().Context.getSubstTemplateTypeParmPackType(
        NewReplaced, T->getIndex(), T->getFinal(), T->getArgumentPack());
  SubstTemplateTypeParmPackTypeLoc NewTL =
      TLB.push<SubstTemplateTypeParmPackTypeLoc>(Result);
  NewTL.setNameLoc(TL.getNameLoc());
  return Result;
}

TemplateArgument Pack = T->getArgumentPack();
TemplateArgument Arg = getPackSubstitutedTemplateArgument(getSema(), Pack);
return BuildSubstTemplateTypeParmType(
    TLB, SuppressObjCLifetime, T->getFinal(), NewReplaced, T->getIndex(),
    getPackIndex(Pack), Arg, TL.getNameLoc());
2194}

2196template<typename EntityPrinter>
2197static concepts::Requirement::SubstitutionDiagnostic *
2198createSubstDiag(Sema &S, TemplateDeductionInfo &Info, EntityPrinter Printer) {
SmallString<128> Message;
SourceLocation ErrorLoc;
if (Info.hasSFINAEDiagnostic()) {
  PartialDiagnosticAt PDA(SourceLocation(),
                          PartialDiagnostic::NullDiagnostic{});
  Info.takeSFINAEDiagnostic(PDA);
  PDA.second.EmitToString(S.getDiagnostics(), Message);
  ErrorLoc = PDA.first;
} else {
  ErrorLoc = Info.getLocation();
}
char *MessageBuf = new (S.Context) char[Message.size()];
std::copy(Message.begin(), Message.end(), MessageBuf);
SmallString<128> Entity;
llvm::raw_svector_ostream OS(Entity);
Printer(OS);
char *EntityBuf = new (S.Context) char[Entity.size()];
std::copy(Entity.begin(), Entity.end(), EntityBuf);
return new (S.Context) concepts::Requirement::SubstitutionDiagnostic{
    StringRef(EntityBuf, Entity.size()), ErrorLoc,
    StringRef(MessageBuf, Message.size())};
2220}

2222ExprResult TemplateInstantiator::TransformRequiresTypeParams(
  SourceLocation KWLoc, SourceLocation RBraceLoc, const RequiresExpr *RE,
  RequiresExprBodyDecl *Body, ArrayRef<ParmVarDecl *> Params,
  SmallVectorImpl<QualType> &PTypes,
  SmallVectorImpl<ParmVarDecl *> &TransParams,
  Sema::ExtParameterInfoBuilder &PInfos) {

TemplateDeductionInfo Info(KWLoc);
Sema::InstantiatingTemplate TypeInst(SemaRef, KWLoc,
                                     RE, Info,
                                     SourceRange{KWLoc, RBraceLoc});
Sema::SFINAETrap Trap(SemaRef);

unsigned ErrorIdx;
if (getDerived().TransformFunctionTypeParams(
        KWLoc, Params, /*ParamTypes=*/nullptr, /*ParamInfos=*/nullptr, PTypes,
        &TransParams, PInfos, &ErrorIdx) ||
    Trap.hasErrorOccurred()) {
  SmallVector<concepts::Requirement *, 4> TransReqs;
  ParmVarDecl *FailedDecl = Params[ErrorIdx];
  // Add a 'failed' Requirement to contain the error that caused the failure
  // here.
  TransReqs.push_back(RebuildTypeRequirement(createSubstDiag(
      SemaRef, Info, [&](llvm::raw_ostream &OS) { OS << *FailedDecl; })));
  return getDerived().RebuildRequiresExpr(KWLoc, Body, TransParams, TransReqs,
                                          RBraceLoc);
}

return ExprResult{};
2251}

2253concepts::TypeRequirement *
2254TemplateInstantiator::TransformTypeRequirement(concepts::TypeRequirement *Req) {
if (!Req->isDependent() && !AlwaysRebuild())
  return Req;
if (Req->isSubstitutionFailure()) {
  if (AlwaysRebuild())
    return RebuildTypeRequirement(
            Req->getSubstitutionDiagnostic());
  return Req;
}

Sema::SFINAETrap Trap(SemaRef);
TemplateDeductionInfo Info(Req->getType()->getTypeLoc().getBeginLoc());
Sema::InstantiatingTemplate TypeInst(SemaRef,
    Req->getType()->getTypeLoc().getBeginLoc(), Req, Info,
    Req->getType()->getTypeLoc().getSourceRange());
if (TypeInst.isInvalid())
  return nullptr;
TypeSourceInfo *TransType = TransformType(Req->getType());
if (!TransType || Trap.hasErrorOccurred())
  return RebuildTypeRequirement(createSubstDiag(SemaRef, Info,
      [&] (llvm::raw_ostream& OS) {
          Req->getType()->getType().print(OS, SemaRef.getPrintingPolicy());
      }));
return RebuildTypeRequirement(TransType);
2278}

2280concepts::ExprRequirement *
2281TemplateInstantiator::TransformExprRequirement(concepts::ExprRequirement *Req) {
if (!Req->isDependent() && !AlwaysRebuild())
  return Req;

Sema::SFINAETrap Trap(SemaRef);

llvm::PointerUnion<Expr *, concepts::Requirement::SubstitutionDiagnostic *>
    TransExpr;
if (Req->isExprSubstitutionFailure())
  TransExpr = Req->getExprSubstitutionDiagnostic();
else {
  Expr *E = Req->getExpr();
  TemplateDeductionInfo Info(E->getBeginLoc());
  Sema::InstantiatingTemplate ExprInst(SemaRef, E->getBeginLoc(), Req, Info,
                                       E->getSourceRange());
  if (ExprInst.isInvalid())
    return nullptr;
  ExprResult TransExprRes = TransformExpr(E);
  if (!TransExprRes.isInvalid() && !Trap.hasErrorOccurred() &&
      TransExprRes.get()->hasPlaceholderType())
    TransExprRes = SemaRef.CheckPlaceholderExpr(TransExprRes.get());
  if (TransExprRes.isInvalid() || Trap.hasErrorOccurred())
    TransExpr = createSubstDiag(SemaRef, Info, [&](llvm::raw_ostream &OS) {
      E->printPretty(OS, nullptr, SemaRef.getPrintingPolicy());
    });
  else
    TransExpr = TransExprRes.get();
}

std::optional<concepts::ExprRequirement::ReturnTypeRequirement> TransRetReq;
const auto &RetReq = Req->getReturnTypeRequirement();
if (RetReq.isEmpty())
  TransRetReq.emplace();
else if (RetReq.isSubstitutionFailure())
  TransRetReq.emplace(RetReq.getSubstitutionDiagnostic());
else if (RetReq.isTypeConstraint()) {
  TemplateParameterList *OrigTPL =
      RetReq.getTypeConstraintTemplateParameterList();
  TemplateDeductionInfo Info(OrigTPL->getTemplateLoc());
  Sema::InstantiatingTemplate TPLInst(SemaRef, OrigTPL->getTemplateLoc(),
                                      Req, Info, OrigTPL->getSourceRange());
  if (TPLInst.isInvalid())
    return nullptr;
  TemplateParameterList *TPL = TransformTemplateParameterList(OrigTPL);
  if (!TPL)
    TransRetReq.emplace(createSubstDiag(SemaRef, Info,
        [&] (llvm::raw_ostream& OS) {
            RetReq.getTypeConstraint()->getImmediatelyDeclaredConstraint()
                ->printPretty(OS, nullptr, SemaRef.getPrintingPolicy());
        }));
  else {
    TPLInst.Clear();
    TransRetReq.emplace(TPL);
  }
}
assert(TransRetReq && "All code paths leading here must set TransRetReq")(static_cast <bool> (TransRetReq && "All code paths leading here must set TransRetReq"
) ? void (0) : __assert_fail ("TransRetReq && \"All code paths leading here must set TransRetReq\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2336, __extension__
 __PRETTY_FUNCTION__));
if (Expr *E = TransExpr.dyn_cast<Expr *>())
  return RebuildExprRequirement(E, Req->isSimple(), Req->getNoexceptLoc(),
                                std::move(*TransRetReq));
return RebuildExprRequirement(
    TransExpr.get<concepts::Requirement::SubstitutionDiagnostic *>(),
    Req->isSimple(), Req->getNoexceptLoc(), std::move(*TransRetReq));
2343}

2345concepts::NestedRequirement *
2346TemplateInstantiator::TransformNestedRequirement(
  concepts::NestedRequirement *Req) {
if (!Req->isDependent() && !AlwaysRebuild())
  return Req;
if (Req->hasInvalidConstraint()) {
  if (AlwaysRebuild())
    return RebuildNestedRequirement(Req->getInvalidConstraintEntity(),
                                    Req->getConstraintSatisfaction());
  return Req;
}
Sema::InstantiatingTemplate ReqInst(SemaRef,
    Req->getConstraintExpr()->getBeginLoc(), Req,
    Sema::InstantiatingTemplate::ConstraintsCheck{},
    Req->getConstraintExpr()->getSourceRange());

ExprResult TransConstraint;
ConstraintSatisfaction Satisfaction;
TemplateDeductionInfo Info(Req->getConstraintExpr()->getBeginLoc());
{
  EnterExpressionEvaluationContext ContextRAII(
      SemaRef, Sema::ExpressionEvaluationContext::ConstantEvaluated);
  Sema::SFINAETrap Trap(SemaRef);
  Sema::InstantiatingTemplate ConstrInst(SemaRef,
      Req->getConstraintExpr()->getBeginLoc(), Req, Info,
      Req->getConstraintExpr()->getSourceRange());
  if (ConstrInst.isInvalid())
    return nullptr;
  llvm::SmallVector<Expr *> Result;
  if (!SemaRef.CheckConstraintSatisfaction(
          nullptr, {Req->getConstraintExpr()}, Result, TemplateArgs,
          Req->getConstraintExpr()->getSourceRange(), Satisfaction) &&
      !Result.empty())
    TransConstraint = Result[0];
  assert(!Trap.hasErrorOccurred() && "Substitution failures must be handled "(static_cast <bool> (!Trap.hasErrorOccurred() &&
 "Substitution failures must be handled " "by CheckConstraintSatisfaction."
) ? void (0) : __assert_fail ("!Trap.hasErrorOccurred() && \"Substitution failures must be handled \" \"by CheckConstraintSatisfaction.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2380, __extension__
 __PRETTY_FUNCTION__))
                                     "by CheckConstraintSatisfaction.")(static_cast <bool> (!Trap.hasErrorOccurred() &&
 "Substitution failures must be handled " "by CheckConstraintSatisfaction."
) ? void (0) : __assert_fail ("!Trap.hasErrorOccurred() && \"Substitution failures must be handled \" \"by CheckConstraintSatisfaction.\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2380, __extension__
 __PRETTY_FUNCTION__));
}
if (TransConstraint.isUsable() &&
    TransConstraint.get()->isInstantiationDependent())
  return new (SemaRef.Context)
      concepts::NestedRequirement(TransConstraint.get());
if (TransConstraint.isInvalid() || !TransConstraint.get() ||
    Satisfaction.HasSubstitutionFailure()) {
  SmallString<128> Entity;
  llvm::raw_svector_ostream OS(Entity);
  Req->getConstraintExpr()->printPretty(OS, nullptr,
                                        SemaRef.getPrintingPolicy());
  char *EntityBuf = new (SemaRef.Context) char[Entity.size()];
  std::copy(Entity.begin(), Entity.end(), EntityBuf);
  return new (SemaRef.Context) concepts::NestedRequirement(
      SemaRef.Context, StringRef(EntityBuf, Entity.size()), Satisfaction);
}
return new (SemaRef.Context) concepts::NestedRequirement(
    SemaRef.Context, TransConstraint.get(), Satisfaction);
2399}


2402/// Perform substitution on the type T with a given set of template
2403/// arguments.
2404///
2405/// This routine substitutes the given template arguments into the
2406/// type T and produces the instantiated type.
2407///
2408/// \param T the type into which the template arguments will be
2409/// substituted. If this type is not dependent, it will be returned
2410/// immediately.
2411///
2412/// \param Args the template arguments that will be
2413/// substituted for the top-level template parameters within T.
2414///
2415/// \param Loc the location in the source code where this substitution
2416/// is being performed. It will typically be the location of the
2417/// declarator (if we're instantiating the type of some declaration)
2418/// or the location of the type in the source code (if, e.g., we're
2419/// instantiating the type of a cast expression).
2420///
2421/// \param Entity the name of the entity associated with a declaration
2422/// being instantiated (if any). May be empty to indicate that there
2423/// is no such entity (if, e.g., this is a type that occurs as part of
2424/// a cast expression) or that the entity has no name (e.g., an
2425/// unnamed function parameter).
2426///
2427/// \param AllowDeducedTST Whether a DeducedTemplateSpecializationType is
2428/// acceptable as the top level type of the result.
2429///
2430/// \returns If the instantiation succeeds, the instantiated
2431/// type. Otherwise, produces diagnostics and returns a NULL type.
2432TypeSourceInfo *Sema::SubstType(TypeSourceInfo *T,
                              const MultiLevelTemplateArgumentList &Args,
                              SourceLocation Loc,
                              DeclarationName Entity,
                              bool AllowDeducedTST) {
assert(!CodeSynthesisContexts.empty() &&(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2439, __extension__
 __PRETTY_FUNCTION__))
       "Cannot perform an instantiation without some context on the "(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2439, __extension__
 __PRETTY_FUNCTION__))
       "instantiation stack")(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2439, __extension__
 __PRETTY_FUNCTION__));

if (!T->getType()->isInstantiationDependentType() &&
    !T->getType()->isVariablyModifiedType())
  return T;

TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
return AllowDeducedTST ? Instantiator.TransformTypeWithDeducedTST(T)
                       : Instantiator.TransformType(T);
2448}

2450TypeSourceInfo *Sema::SubstType(TypeLoc TL,
                              const MultiLevelTemplateArgumentList &Args,
                              SourceLocation Loc,
                              DeclarationName Entity) {
assert(!CodeSynthesisContexts.empty() &&(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2456, __extension__
 __PRETTY_FUNCTION__))
       "Cannot perform an instantiation without some context on the "(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2456, __extension__
 __PRETTY_FUNCTION__))
       "instantiation stack")(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2456, __extension__
 __PRETTY_FUNCTION__));

if (TL.getType().isNull())
  return nullptr;

if (!TL.getType()->isInstantiationDependentType() &&
    !TL.getType()->isVariablyModifiedType()) {
  // FIXME: Make a copy of the TypeLoc data here, so that we can
  // return a new TypeSourceInfo. Inefficient!
  TypeLocBuilder TLB;
  TLB.pushFullCopy(TL);
  return TLB.getTypeSourceInfo(Context, TL.getType());
}

TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
TypeLocBuilder TLB;
TLB.reserve(TL.getFullDataSize());
QualType Result = Instantiator.TransformType(TLB, TL);
if (Result.isNull())
  return nullptr;

return TLB.getTypeSourceInfo(Context, Result);
2478}

2480/// Deprecated form of the above.
2481QualType Sema::SubstType(QualType T,
                       const MultiLevelTemplateArgumentList &TemplateArgs,
                       SourceLocation Loc, DeclarationName Entity) {
assert(!CodeSynthesisContexts.empty() &&(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2486, __extension__
 __PRETTY_FUNCTION__))
       "Cannot perform an instantiation without some context on the "(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2486, __extension__
 __PRETTY_FUNCTION__))
       "instantiation stack")(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2486, __extension__
 __PRETTY_FUNCTION__));

// If T is not a dependent type or a variably-modified type, there
// is nothing to do.
if (!T->isInstantiationDependentType() && !T->isVariablyModifiedType())
  return T;

TemplateInstantiator Instantiator(*this, TemplateArgs, Loc, Entity);
return Instantiator.TransformType(T);
2495}

2497static bool NeedsInstantiationAsFunctionType(TypeSourceInfo *T) {
if (T->getType()->isInstantiationDependentType() ||
    T->getType()->isVariablyModifiedType())
  return true;

TypeLoc TL = T->getTypeLoc().IgnoreParens();
if (!TL.getAs<FunctionProtoTypeLoc>())
  return false;

FunctionProtoTypeLoc FP = TL.castAs<FunctionProtoTypeLoc>();
for (ParmVarDecl *P : FP.getParams()) {
  // This must be synthesized from a typedef.
  if (!P) continue;

  // If there are any parameters, a new TypeSourceInfo that refers to the
  // instantiated parameters must be built.
  return true;
}

return false;
2517}

2519/// A form of SubstType intended specifically for instantiating the
2520/// type of a FunctionDecl.  Its purpose is solely to force the
2521/// instantiation of default-argument expressions and to avoid
2522/// instantiating an exception-specification.
2523TypeSourceInfo *Sema::SubstFunctionDeclType(TypeSourceInfo *T,
                              const MultiLevelTemplateArgumentList &Args,
                              SourceLocation Loc,
                              DeclarationName Entity,
                              CXXRecordDecl *ThisContext,
                              Qualifiers ThisTypeQuals,
                              bool EvaluateConstraints) {
assert(!CodeSynthesisContexts.empty() &&(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2532, __extension__
 __PRETTY_FUNCTION__))
       "Cannot perform an instantiation without some context on the "(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2532, __extension__
 __PRETTY_FUNCTION__))
       "instantiation stack")(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2532, __extension__
 __PRETTY_FUNCTION__));

if (!NeedsInstantiationAsFunctionType(T))
  return T;

TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
Instantiator.setEvaluateConstraints(EvaluateConstraints);

TypeLocBuilder TLB;

TypeLoc TL = T->getTypeLoc();
TLB.reserve(TL.getFullDataSize());

QualType Result;

if (FunctionProtoTypeLoc Proto =
        TL.IgnoreParens().getAs<FunctionProtoTypeLoc>()) {
  // Instantiate the type, other than its exception specification. The
  // exception specification is instantiated in InitFunctionInstantiation
  // once we've built the FunctionDecl.
  // FIXME: Set the exception specification to EST_Uninstantiated here,
  // instead of rebuilding the function type again later.
  Result = Instantiator.TransformFunctionProtoType(
      TLB, Proto, ThisContext, ThisTypeQuals,
      [](FunctionProtoType::ExceptionSpecInfo &ESI,
         bool &Changed) { return false; });
} else {
  Result = Instantiator.TransformType(TLB, TL);
}
if (Result.isNull())
  return nullptr;

return TLB.getTypeSourceInfo(Context, Result);
2565}

2567bool Sema::SubstExceptionSpec(SourceLocation Loc,
                            FunctionProtoType::ExceptionSpecInfo &ESI,
                            SmallVectorImpl<QualType> &ExceptionStorage,
                            const MultiLevelTemplateArgumentList &Args) {
assert(ESI.Type != EST_Uninstantiated)(static_cast <bool> (ESI.Type != EST_Uninstantiated) ? void
 (0) : __assert_fail ("ESI.Type != EST_Uninstantiated", "clang/lib/Sema/SemaTemplateInstantiate.cpp"
, 2571, __extension__ __PRETTY_FUNCTION__));

bool Changed = false;
TemplateInstantiator Instantiator(*this, Args, Loc, DeclarationName());
return Instantiator.TransformExceptionSpec(Loc, ESI, ExceptionStorage,
                                           Changed);
2577}

2579void Sema::SubstExceptionSpec(FunctionDecl *New, const FunctionProtoType *Proto,
                            const MultiLevelTemplateArgumentList &Args) {
FunctionProtoType::ExceptionSpecInfo ESI =
    Proto->getExtProtoInfo().ExceptionSpec;

SmallVector<QualType, 4> ExceptionStorage;
if (SubstExceptionSpec(New->getTypeSourceInfo()->getTypeLoc().getEndLoc(),
                       ESI, ExceptionStorage, Args))
  // On error, recover by dropping the exception specification.
  ESI.Type = EST_None;

UpdateExceptionSpec(New, ESI);
2591}

2593namespace {

struct GetContainedInventedTypeParmVisitor :
  public TypeVisitor<GetContainedInventedTypeParmVisitor,
                     TemplateTypeParmDecl *> {
  using TypeVisitor<GetContainedInventedTypeParmVisitor,
                    TemplateTypeParmDecl *>::Visit;

  TemplateTypeParmDecl *Visit(QualType T) {
    if (T.isNull())
      return nullptr;
    return Visit(T.getTypePtr());
  }
  // The deduced type itself.
  TemplateTypeParmDecl *VisitTemplateTypeParmType(
      const TemplateTypeParmType *T) {
    if (!T->getDecl() || !T->getDecl()->isImplicit())
      return nullptr;
    return T->getDecl();
  }

  // Only these types can contain 'auto' types, and subsequently be replaced
  // by references to invented parameters.

  TemplateTypeParmDecl *VisitElaboratedType(const ElaboratedType *T) {
    return Visit(T->getNamedType());
  }

  TemplateTypeParmDecl *VisitPointerType(const PointerType *T) {
    return Visit(T->getPointeeType());
  }

  TemplateTypeParmDecl *VisitBlockPointerType(const BlockPointerType *T) {
    return Visit(T->getPointeeType());
  }

  TemplateTypeParmDecl *VisitReferenceType(const ReferenceType *T) {
    return Visit(T->getPointeeTypeAsWritten());
  }

  TemplateTypeParmDecl *VisitMemberPointerType(const MemberPointerType *T) {
    return Visit(T->getPointeeType());
  }

  TemplateTypeParmDecl *VisitArrayType(const ArrayType *T) {
    return Visit(T->getElementType());
  }

  TemplateTypeParmDecl *VisitDependentSizedExtVectorType(
    const DependentSizedExtVectorType *T) {
    return Visit(T->getElementType());
  }

  TemplateTypeParmDecl *VisitVectorType(const VectorType *T) {
    return Visit(T->getElementType());
  }

  TemplateTypeParmDecl *VisitFunctionProtoType(const FunctionProtoType *T) {
    return VisitFunctionType(T);
  }

  TemplateTypeParmDecl *VisitFunctionType(const FunctionType *T) {
    return Visit(T->getReturnType());
  }

  TemplateTypeParmDecl *VisitParenType(const ParenType *T) {
    return Visit(T->getInnerType());
  }

  TemplateTypeParmDecl *VisitAttributedType(const AttributedType *T) {
    return Visit(T->getModifiedType());
  }

  TemplateTypeParmDecl *VisitMacroQualifiedType(const MacroQualifiedType *T) {
    return Visit(T->getUnderlyingType());
  }

  TemplateTypeParmDecl *VisitAdjustedType(const AdjustedType *T) {
    return Visit(T->getOriginalType());
  }

  TemplateTypeParmDecl *VisitPackExpansionType(const PackExpansionType *T) {
    return Visit(T->getPattern());
  }
};

2679} // namespace

2681bool Sema::SubstTypeConstraint(
  TemplateTypeParmDecl *Inst, const TypeConstraint *TC,
  const MultiLevelTemplateArgumentList &TemplateArgs,
  bool EvaluateConstraints) {
const ASTTemplateArgumentListInfo *TemplArgInfo =
    TC->getTemplateArgsAsWritten();

if (!EvaluateConstraints) {
  Inst->setTypeConstraint(TC->getNestedNameSpecifierLoc(),
                          TC->getConceptNameInfo(), TC->getNamedConcept(),
                          TC->getNamedConcept(), TemplArgInfo,
                          TC->getImmediatelyDeclaredConstraint());
  return false;
}

TemplateArgumentListInfo InstArgs;

if (TemplArgInfo) {
  InstArgs.setLAngleLoc(TemplArgInfo->LAngleLoc);
  InstArgs.setRAngleLoc(TemplArgInfo->RAngleLoc);
  if (SubstTemplateArguments(TemplArgInfo->arguments(), TemplateArgs,
                             InstArgs))
    return true;
}
return AttachTypeConstraint(
    TC->getNestedNameSpecifierLoc(), TC->getConceptNameInfo(),
    TC->getNamedConcept(), &InstArgs, Inst,
    Inst->isParameterPack()
        ? cast<CXXFoldExpr>(TC->getImmediatelyDeclaredConstraint())
              ->getEllipsisLoc()
        : SourceLocation());
2712}

2714ParmVarDecl *Sema::SubstParmVarDecl(
  ParmVarDecl *OldParm, const MultiLevelTemplateArgumentList &TemplateArgs,
  int indexAdjustment, std::optional<unsigned> NumExpansions,
  bool ExpectParameterPack, bool EvaluateConstraint) {
TypeSourceInfo *OldDI = OldParm->getTypeSourceInfo();
TypeSourceInfo *NewDI = nullptr;

TypeLoc OldTL = OldDI->getTypeLoc();
if (PackExpansionTypeLoc ExpansionTL = OldTL.getAs<PackExpansionTypeLoc>()) {

  // We have a function parameter pack. Substitute into the pattern of the
  // expansion.
  NewDI = SubstType(ExpansionTL.getPatternLoc(), TemplateArgs,
                    OldParm->getLocation(), OldParm->getDeclName());
  if (!NewDI)
    return nullptr;

  if (NewDI->getType()->containsUnexpandedParameterPack()) {
    // We still have unexpanded parameter packs, which means that
    // our function parameter is still a function parameter pack.
    // Therefore, make its type a pack expansion type.
    NewDI = CheckPackExpansion(NewDI, ExpansionTL.getEllipsisLoc(),
                               NumExpansions);
  } else if (ExpectParameterPack) {
    // We expected to get a parameter pack but didn't (because the type
    // itself is not a pack expansion type), so complain. This can occur when
    // the substitution goes through an alias template that "loses" the
    // pack expansion.
    Diag(OldParm->getLocation(),
         diag::err_function_parameter_pack_without_parameter_packs)
      << NewDI->getType();
    return nullptr;
  }
} else {
  NewDI = SubstType(OldDI, TemplateArgs, OldParm->getLocation(),
                    OldParm->getDeclName());
}

if (!NewDI)
  return nullptr;

if (NewDI->getType()->isVoidType()) {
  Diag(OldParm->getLocation(), diag::err_param_with_void_type);
  return nullptr;
}

// In abbreviated templates, TemplateTypeParmDecls with possible
// TypeConstraints are created when the parameter list is originally parsed.
// The TypeConstraints can therefore reference other functions parameters in
// the abbreviated function template, which is why we must instantiate them
// here, when the instantiated versions of those referenced parameters are in
// scope.
if (TemplateTypeParmDecl *TTP =
        GetContainedInventedTypeParmVisitor().Visit(OldDI->getType())) {
  if (const TypeConstraint *TC = TTP->getTypeConstraint()) {
    auto *Inst = cast_or_null<TemplateTypeParmDecl>(
        FindInstantiatedDecl(TTP->getLocation(), TTP, TemplateArgs));
    // We will first get here when instantiating the abbreviated function
    // template's described function, but we might also get here later.
    // Make sure we do not instantiate the TypeConstraint more than once.
    if (Inst && !Inst->getTypeConstraint()) {
      if (SubstTypeConstraint(Inst, TC, TemplateArgs, EvaluateConstraint))
        return nullptr;
    }
  }
}

ParmVarDecl *NewParm = CheckParameter(Context.getTranslationUnitDecl(),
                                      OldParm->getInnerLocStart(),
                                      OldParm->getLocation(),
                                      OldParm->getIdentifier(),
                                      NewDI->getType(), NewDI,
                                      OldParm->getStorageClass());
if (!NewParm)
  return nullptr;

// Mark the (new) default argument as uninstantiated (if any).
if (OldParm->hasUninstantiatedDefaultArg()) {
  Expr *Arg = OldParm->getUninstantiatedDefaultArg();
  NewParm->setUninstantiatedDefaultArg(Arg);
} else if (OldParm->hasUnparsedDefaultArg()) {
  NewParm->setUnparsedDefaultArg();
  UnparsedDefaultArgInstantiations[OldParm].push_back(NewParm);
} else if (Expr *Arg = OldParm->getDefaultArg()) {
  // Default arguments cannot be substituted until the declaration context
  // for the associated function or lambda capture class is available.
  // This is necessary for cases like the following where construction of
  // the lambda capture class for the outer lambda is dependent on the
  // parameter types but where the default argument is dependent on the
  // outer lambda's declaration context.
  //   template <typename T>
  //   auto f() {
  //     return [](T = []{ return T{}; }()) { return 0; };
  //   }
  NewParm->setUninstantiatedDefaultArg(Arg);
}

NewParm->setHasInheritedDefaultArg(OldParm->hasInheritedDefaultArg());

if (OldParm->isParameterPack() && !NewParm->isParameterPack()) {
  // Add the new parameter to the instantiated parameter pack.
  CurrentInstantiationScope->InstantiatedLocalPackArg(OldParm, NewParm);
} else {
  // Introduce an Old -> New mapping
  CurrentInstantiationScope->InstantiatedLocal(OldParm, NewParm);
}

// FIXME: OldParm may come from a FunctionProtoType, in which case CurContext
// can be anything, is this right ?
NewParm->setDeclContext(CurContext);

NewParm->setScopeInfo(OldParm->getFunctionScopeDepth(),
                      OldParm->getFunctionScopeIndex() + indexAdjustment);

InstantiateAttrs(TemplateArgs, OldParm, NewParm);

return NewParm;
2831}

2833/// Substitute the given template arguments into the given set of
2834/// parameters, producing the set of parameter types that would be generated
2835/// from such a substitution.
2836bool Sema::SubstParmTypes(
  SourceLocation Loc, ArrayRef<ParmVarDecl *> Params,
  const FunctionProtoType::ExtParameterInfo *ExtParamInfos,
  const MultiLevelTemplateArgumentList &TemplateArgs,
  SmallVectorImpl<QualType> &ParamTypes,
  SmallVectorImpl<ParmVarDecl *> *OutParams,
  ExtParameterInfoBuilder &ParamInfos) {
assert(!CodeSynthesisContexts.empty() &&(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2845, __extension__
 __PRETTY_FUNCTION__))
       "Cannot perform an instantiation without some context on the "(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2845, __extension__
 __PRETTY_FUNCTION__))
       "instantiation stack")(static_cast <bool> (!CodeSynthesisContexts.empty() &&
 "Cannot perform an instantiation without some context on the "
 "instantiation stack") ? void (0) : __assert_fail ("!CodeSynthesisContexts.empty() && \"Cannot perform an instantiation without some context on the \" \"instantiation stack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 2845, __extension__
 __PRETTY_FUNCTION__));

TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
                                  DeclarationName());
return Instantiator.TransformFunctionTypeParams(
    Loc, Params, nullptr, ExtParamInfos, ParamTypes, OutParams, ParamInfos);
2851}

2853/// Substitute the given template arguments into the default argument.
2854bool Sema::SubstDefaultArgument(
  SourceLocation Loc,
  ParmVarDecl *Param,
  const MultiLevelTemplateArgumentList &TemplateArgs,
  bool ForCallExpr) {
FunctionDecl *FD = cast<FunctionDecl>(Param->getDeclContext());
Expr *PatternExpr = Param->getUninstantiatedDefaultArg();

EnterExpressionEvaluationContext EvalContext(
    *this, ExpressionEvaluationContext::PotentiallyEvaluated, Param);

InstantiatingTemplate Inst(*this, Loc, Param, TemplateArgs.getInnermost());
if (Inst.isInvalid())
  return true;
if (Inst.isAlreadyInstantiating()) {
  Diag(Param->getBeginLoc(), diag::err_recursive_default_argument) << FD;
  Param->setInvalidDecl();
  return true;
}

ExprResult Result;
{
  // C++ [dcl.fct.default]p5:
  //   The names in the [default argument] expression are bound, and
  //   the semantic constraints are checked, at the point where the
  //   default argument expression appears.
  ContextRAII SavedContext(*this, FD);
  std::unique_ptr<LocalInstantiationScope> LIS;

  if (ForCallExpr) {
    // When instantiating a default argument due to use in a call expression,
    // an instantiation scope that includes the parameters of the callee is
    // required to satisfy references from the default argument. For example:
    //   template<typename T> void f(T a, int = decltype(a)());
    //   void g() { f(0); }
    LIS = std::make_unique<LocalInstantiationScope>(*this);
    FunctionDecl *PatternFD = FD->getTemplateInstantiationPattern(
        /*ForDefinition*/ false);
    if (addInstantiatedParametersToScope(FD, PatternFD, *LIS, TemplateArgs))
      return true;
  }

  runWithSufficientStackSpace(Loc, [&] {
    Result = SubstInitializer(PatternExpr, TemplateArgs,
                              /*DirectInit*/false);
  });
}
if (Result.isInvalid())
  return true;

if (ForCallExpr) {
  // Check the expression as an initializer for the parameter.
  InitializedEntity Entity
    = InitializedEntity::InitializeParameter(Context, Param);
  InitializationKind Kind = InitializationKind::CreateCopy(
      Param->getLocation(),
      /*FIXME:EqualLoc*/ PatternExpr->getBeginLoc());
  Expr *ResultE = Result.getAs<Expr>();

  InitializationSequence InitSeq(*this, Entity, Kind, ResultE);
  Result = InitSeq.Perform(*this, Entity, Kind, ResultE);
  if (Result.isInvalid())
    return true;

  Result =
      ActOnFinishFullExpr(Result.getAs<Expr>(), Param->getOuterLocStart(),
                          /*DiscardedValue*/ false);
} else {
  // FIXME: Obtain the source location for the '=' token.
  SourceLocation EqualLoc = PatternExpr->getBeginLoc();
  Result = ConvertParamDefaultArgument(Param, Result.getAs<Expr>(), EqualLoc);
}
if (Result.isInvalid())
    return true;

// Remember the instantiated default argument.
Param->setDefaultArg(Result.getAs<Expr>());

return false;
2933}

2935/// Perform substitution on the base class specifiers of the
2936/// given class template specialization.
2937///
2938/// Produces a diagnostic and returns true on error, returns false and
2939/// attaches the instantiated base classes to the class template
2940/// specialization if successful.
2941bool
2942Sema::SubstBaseSpecifiers(CXXRecordDecl *Instantiation,
                        CXXRecordDecl *Pattern,
                        const MultiLevelTemplateArgumentList &TemplateArgs) {
bool Invalid = false;
SmallVector<CXXBaseSpecifier*, 4> InstantiatedBases;
for (const auto &Base : Pattern->bases()) {
  if (!Base.getType()->isDependentType()) {
    if (const CXXRecordDecl *RD = Base.getType()->getAsCXXRecordDecl()) {
      if (RD->isInvalidDecl())
        Instantiation->setInvalidDecl();
    }
    InstantiatedBases.push_back(new (Context) CXXBaseSpecifier(Base));
    continue;
  }

  SourceLocation EllipsisLoc;
  TypeSourceInfo *BaseTypeLoc;
  if (Base.isPackExpansion()) {
    // This is a pack expansion. See whether we should expand it now, or
    // wait until later.
    SmallVector<UnexpandedParameterPack, 2> Unexpanded;
    collectUnexpandedParameterPacks(Base.getTypeSourceInfo()->getTypeLoc(),
                                    Unexpanded);
    bool ShouldExpand = false;
    bool RetainExpansion = false;
    std::optional<unsigned> NumExpansions;
    if (CheckParameterPacksForExpansion(Base.getEllipsisLoc(),
                                        Base.getSourceRange(),
                                        Unexpanded,
                                        TemplateArgs, ShouldExpand,
                                        RetainExpansion,
                                        NumExpansions)) {
      Invalid = true;
      continue;
    }

    // If we should expand this pack expansion now, do so.
    if (ShouldExpand) {
      for (unsigned I = 0; I != *NumExpansions; ++I) {
          Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);

        TypeSourceInfo *BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
                                                TemplateArgs,
                                            Base.getSourceRange().getBegin(),
                                                DeclarationName());
        if (!BaseTypeLoc) {
          Invalid = true;
          continue;
        }

        if (CXXBaseSpecifier *InstantiatedBase
              = CheckBaseSpecifier(Instantiation,
                                   Base.getSourceRange(),
                                   Base.isVirtual(),
                                   Base.getAccessSpecifierAsWritten(),
                                   BaseTypeLoc,
                                   SourceLocation()))
          InstantiatedBases.push_back(InstantiatedBase);
        else
          Invalid = true;
      }

      continue;
    }

    // The resulting base specifier will (still) be a pack expansion.
    EllipsisLoc = Base.getEllipsisLoc();
    Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, -1);
    BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
                            TemplateArgs,
                            Base.getSourceRange().getBegin(),
                            DeclarationName());
  } else {
    BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
                            TemplateArgs,
                            Base.getSourceRange().getBegin(),
                            DeclarationName());
  }

  if (!BaseTypeLoc) {
    Invalid = true;
    continue;
  }

  if (CXXBaseSpecifier *InstantiatedBase
        = CheckBaseSpecifier(Instantiation,
                             Base.getSourceRange(),
                             Base.isVirtual(),
                             Base.getAccessSpecifierAsWritten(),
                             BaseTypeLoc,
                             EllipsisLoc))
    InstantiatedBases.push_back(InstantiatedBase);
  else
    Invalid = true;
}

if (!Invalid && AttachBaseSpecifiers(Instantiation, InstantiatedBases))
  Invalid = true;

return Invalid;
3042}

3044// Defined via #include from SemaTemplateInstantiateDecl.cpp
3045namespace clang {
namespace sema {
  Attr *instantiateTemplateAttribute(const Attr *At, ASTContext &C, Sema &S,
                          const MultiLevelTemplateArgumentList &TemplateArgs);
  Attr *instantiateTemplateAttributeForDecl(
      const Attr *At, ASTContext &C, Sema &S,
      const MultiLevelTemplateArgumentList &TemplateArgs);
}
3053}

3055/// Instantiate the definition of a class from a given pattern.
3056///
3057/// \param PointOfInstantiation The point of instantiation within the
3058/// source code.
3059///
3060/// \param Instantiation is the declaration whose definition is being
3061/// instantiated. This will be either a class template specialization
3062/// or a member class of a class template specialization.
3063///
3064/// \param Pattern is the pattern from which the instantiation
3065/// occurs. This will be either the declaration of a class template or
3066/// the declaration of a member class of a class template.
3067///
3068/// \param TemplateArgs The template arguments to be substituted into
3069/// the pattern.
3070///
3071/// \param TSK the kind of implicit or explicit instantiation to perform.
3072///
3073/// \param Complain whether to complain if the class cannot be instantiated due
3074/// to the lack of a definition.
3075///
3076/// \returns true if an error occurred, false otherwise.
3077bool
3078Sema::InstantiateClass(SourceLocation PointOfInstantiation,
                     CXXRecordDecl *Instantiation, CXXRecordDecl *Pattern,
                     const MultiLevelTemplateArgumentList &TemplateArgs,
                     TemplateSpecializationKind TSK,
                     bool Complain) {
CXXRecordDecl *PatternDef
  = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Instantiation,
                              Instantiation->getInstantiatedFromMemberClass(),
                                   Pattern, PatternDef, TSK, Complain))
  return true;

llvm::TimeTraceScope TimeScope("InstantiateClass", [&]() {
  std::string Name;
  llvm::raw_string_ostream OS(Name);
  Instantiation->getNameForDiagnostic(OS, getPrintingPolicy(),
                                      /*Qualified=*/true);
  return Name;
});

Pattern = PatternDef;

// Record the point of instantiation.
if (MemberSpecializationInfo *MSInfo
      = Instantiation->getMemberSpecializationInfo()) {
  MSInfo->setTemplateSpecializationKind(TSK);
  MSInfo->setPointOfInstantiation(PointOfInstantiation);
} else if (ClassTemplateSpecializationDecl *Spec
      = dyn_cast<ClassTemplateSpecializationDecl>(Instantiation)) {
  Spec->setTemplateSpecializationKind(TSK);
  Spec->setPointOfInstantiation(PointOfInstantiation);
}

InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
if (Inst.isInvalid())
  return true;
assert(!Inst.isAlreadyInstantiating() && "should have been caught by caller")(static_cast <bool> (!Inst.isAlreadyInstantiating() &&
 "should have been caught by caller") ? void (0) : __assert_fail
 ("!Inst.isAlreadyInstantiating() && \"should have been caught by caller\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3114, __extension__
 __PRETTY_FUNCTION__));
PrettyDeclStackTraceEntry CrashInfo(Context, Instantiation, SourceLocation(),
                                    "instantiating class definition");

// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
ContextRAII SavedContext(*this, Instantiation);
EnterExpressionEvaluationContext EvalContext(
    *this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated);

// If this is an instantiation of a local class, merge this local
// instantiation scope with the enclosing scope. Otherwise, every
// instantiation of a class has its own local instantiation scope.
bool MergeWithParentScope = !Instantiation->isDefinedOutsideFunctionOrMethod();
LocalInstantiationScope Scope(*this, MergeWithParentScope);

// Some class state isn't processed immediately but delayed till class
// instantiation completes. We may not be ready to handle any delayed state
// already on the stack as it might correspond to a different class, so save
// it now and put it back later.
SavePendingParsedClassStateRAII SavedPendingParsedClassState(*this);

// Pull attributes from the pattern onto the instantiation.
InstantiateAttrs(TemplateArgs, Pattern, Instantiation);

// Start the definition of this instantiation.
Instantiation->startDefinition();

// The instantiation is visible here, even if it was first declared in an
// unimported module.
Instantiation->setVisibleDespiteOwningModule();

// FIXME: This loses the as-written tag kind for an explicit instantiation.
Instantiation->setTagKind(Pattern->getTagKind());

// Do substitution on the base class specifiers.
if (SubstBaseSpecifiers(Instantiation, Pattern, TemplateArgs))
  Instantiation->setInvalidDecl();

TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
Instantiator.setEvaluateConstraints(false);
SmallVector<Decl*, 4> Fields;
// Delay instantiation of late parsed attributes.
LateInstantiatedAttrVec LateAttrs;
Instantiator.enableLateAttributeInstantiation(&LateAttrs);

bool MightHaveConstexprVirtualFunctions = false;
for (auto *Member : Pattern->decls()) {
  // Don't instantiate members not belonging in this semantic context.
  // e.g. for:
  // @code
  //    template <int i> class A {
  //      class B *g;
  //    };
  // @endcode
  // 'class B' has the template as lexical context but semantically it is
  // introduced in namespace scope.
  if (Member->getDeclContext() != Pattern)
    continue;

  // BlockDecls can appear in a default-member-initializer. They must be the
  // child of a BlockExpr, so we only know how to instantiate them from there.
  // Similarly, lambda closure types are recreated when instantiating the
  // corresponding LambdaExpr.
  if (isa<BlockDecl>(Member) ||
      (isa<CXXRecordDecl>(Member) && cast<CXXRecordDecl>(Member)->isLambda()))
    continue;

  if (Member->isInvalidDecl()) {
    Instantiation->setInvalidDecl();
    continue;
  }

  Decl *NewMember = Instantiator.Visit(Member);
  if (NewMember) {
    if (FieldDecl *Field = dyn_cast<FieldDecl>(NewMember)) {
      Fields.push_back(Field);
    } else if (EnumDecl *Enum = dyn_cast<EnumDecl>(NewMember)) {
      // C++11 [temp.inst]p1: The implicit instantiation of a class template
      // specialization causes the implicit instantiation of the definitions
      // of unscoped member enumerations.
      // Record a point of instantiation for this implicit instantiation.
      if (TSK == TSK_ImplicitInstantiation && !Enum->isScoped() &&
          Enum->isCompleteDefinition()) {
        MemberSpecializationInfo *MSInfo =Enum->getMemberSpecializationInfo();
        assert(MSInfo && "no spec info for member enum specialization")(static_cast <bool> (MSInfo && "no spec info for member enum specialization"
) ? void (0) : __assert_fail ("MSInfo && \"no spec info for member enum specialization\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3199, __extension__
 __PRETTY_FUNCTION__));
        MSInfo->setTemplateSpecializationKind(TSK_ImplicitInstantiation);
        MSInfo->setPointOfInstantiation(PointOfInstantiation);
      }
    } else if (StaticAssertDecl *SA = dyn_cast<StaticAssertDecl>(NewMember)) {
      if (SA->isFailed()) {
        // A static_assert failed. Bail out; instantiating this
        // class is probably not meaningful.
        Instantiation->setInvalidDecl();
        break;
      }
    } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewMember)) {
      if (MD->isConstexpr() && !MD->getFriendObjectKind() &&
          (MD->isVirtualAsWritten() || Instantiation->getNumBases()))
        MightHaveConstexprVirtualFunctions = true;
    }

    if (NewMember->isInvalidDecl())
      Instantiation->setInvalidDecl();
  } else {
    // FIXME: Eventually, a NULL return will mean that one of the
    // instantiations was a semantic disaster, and we'll want to mark the
    // declaration invalid.
    // For now, we expect to skip some members that we can't yet handle.
  }
}

// Finish checking fields.
ActOnFields(nullptr, Instantiation->getLocation(), Instantiation, Fields,
            SourceLocation(), SourceLocation(), ParsedAttributesView());
CheckCompletedCXXClass(nullptr, Instantiation);

// Default arguments are parsed, if not instantiated. We can go instantiate
// default arg exprs for default constructors if necessary now. Unless we're
// parsing a class, in which case wait until that's finished.
if (ParsingClassDepth == 0)
  ActOnFinishCXXNonNestedClass();

// Instantiate late parsed attributes, and attach them to their decls.
// See Sema::InstantiateAttrs
for (LateInstantiatedAttrVec::iterator I = LateAttrs.begin(),
     E = LateAttrs.end(); I != E; ++I) {
  assert(CurrentInstantiationScope == Instantiator.getStartingScope())(static_cast <bool> (CurrentInstantiationScope == Instantiator
.getStartingScope()) ? void (0) : __assert_fail ("CurrentInstantiationScope == Instantiator.getStartingScope()"
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3241, __extension__
 __PRETTY_FUNCTION__));
  CurrentInstantiationScope = I->Scope;

  // Allow 'this' within late-parsed attributes.
  auto *ND = cast<NamedDecl>(I->NewDecl);
  auto *ThisContext = dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
  CXXThisScopeRAII ThisScope(*this, ThisContext, Qualifiers(),
                             ND->isCXXInstanceMember());

  Attr *NewAttr =
    instantiateTemplateAttribute(I->TmplAttr, Context, *this, TemplateArgs);
  if (NewAttr)
    I->NewDecl->addAttr(NewAttr);
  LocalInstantiationScope::deleteScopes(I->Scope,
                                        Instantiator.getStartingScope());
}
Instantiator.disableLateAttributeInstantiation();
LateAttrs.clear();

ActOnFinishDelayedMemberInitializers(Instantiation);

// FIXME: We should do something similar for explicit instantiations so they
// end up in the right module.
if (TSK == TSK_ImplicitInstantiation) {
  Instantiation->setLocation(Pattern->getLocation());
  Instantiation->setLocStart(Pattern->getInnerLocStart());
  Instantiation->setBraceRange(Pattern->getBraceRange());
}

if (!Instantiation->isInvalidDecl()) {
  // Perform any dependent diagnostics from the pattern.
  if (Pattern->isDependentContext())
    PerformDependentDiagnostics(Pattern, TemplateArgs);

  // Instantiate any out-of-line class template partial
  // specializations now.
  for (TemplateDeclInstantiator::delayed_partial_spec_iterator
            P = Instantiator.delayed_partial_spec_begin(),
         PEnd = Instantiator.delayed_partial_spec_end();
       P != PEnd; ++P) {
    if (!Instantiator.InstantiateClassTemplatePartialSpecialization(
            P->first, P->second)) {
      Instantiation->setInvalidDecl();
      break;
    }
  }

  // Instantiate any out-of-line variable template partial
  // specializations now.
  for (TemplateDeclInstantiator::delayed_var_partial_spec_iterator
            P = Instantiator.delayed_var_partial_spec_begin(),
         PEnd = Instantiator.delayed_var_partial_spec_end();
       P != PEnd; ++P) {
    if (!Instantiator.InstantiateVarTemplatePartialSpecialization(
            P->first, P->second)) {
      Instantiation->setInvalidDecl();
      break;
    }
  }
}

// Exit the scope of this instantiation.
SavedContext.pop();

if (!Instantiation->isInvalidDecl()) {
  // Always emit the vtable for an explicit instantiation definition
  // of a polymorphic class template specialization. Otherwise, eagerly
  // instantiate only constexpr virtual functions in preparation for their use
  // in constant evaluation.
  if (TSK == TSK_ExplicitInstantiationDefinition)
    MarkVTableUsed(PointOfInstantiation, Instantiation, true);
  else if (MightHaveConstexprVirtualFunctions)
    MarkVirtualMembersReferenced(PointOfInstantiation, Instantiation,
                                 /*ConstexprOnly*/ true);
}

Consumer.HandleTagDeclDefinition(Instantiation);

return Instantiation->isInvalidDecl();
3320}

3322/// Instantiate the definition of an enum from a given pattern.
3323///
3324/// \param PointOfInstantiation The point of instantiation within the
3325///        source code.
3326/// \param Instantiation is the declaration whose definition is being
3327///        instantiated. This will be a member enumeration of a class
3328///        temploid specialization, or a local enumeration within a
3329///        function temploid specialization.
3330/// \param Pattern The templated declaration from which the instantiation
3331///        occurs.
3332/// \param TemplateArgs The template arguments to be substituted into
3333///        the pattern.
3334/// \param TSK The kind of implicit or explicit instantiation to perform.
3335///
3336/// \return \c true if an error occurred, \c false otherwise.
3337bool Sema::InstantiateEnum(SourceLocation PointOfInstantiation,
                         EnumDecl *Instantiation, EnumDecl *Pattern,
                         const MultiLevelTemplateArgumentList &TemplateArgs,
                         TemplateSpecializationKind TSK) {
EnumDecl *PatternDef = Pattern->getDefinition();
if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Instantiation,
                               Instantiation->getInstantiatedFromMemberEnum(),
                                   Pattern, PatternDef, TSK,/*Complain*/true))
  return true;
Pattern = PatternDef;

// Record the point of instantiation.
if (MemberSpecializationInfo *MSInfo
      = Instantiation->getMemberSpecializationInfo()) {
  MSInfo->setTemplateSpecializationKind(TSK);
  MSInfo->setPointOfInstantiation(PointOfInstantiation);
}

InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
if (Inst.isInvalid())
  return true;
if (Inst.isAlreadyInstantiating())
  return false;
PrettyDeclStackTraceEntry CrashInfo(Context, Instantiation, SourceLocation(),
                                    "instantiating enum definition");

// The instantiation is visible here, even if it was first declared in an
// unimported module.
Instantiation->setVisibleDespiteOwningModule();

// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
ContextRAII SavedContext(*this, Instantiation);
EnterExpressionEvaluationContext EvalContext(
    *this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated);

LocalInstantiationScope Scope(*this, /*MergeWithParentScope*/true);

// Pull attributes from the pattern onto the instantiation.
InstantiateAttrs(TemplateArgs, Pattern, Instantiation);

TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
Instantiator.InstantiateEnumDefinition(Instantiation, Pattern);

// Exit the scope of this instantiation.
SavedContext.pop();

return Instantiation->isInvalidDecl();
3385}


3388/// Instantiate the definition of a field from the given pattern.
3389///
3390/// \param PointOfInstantiation The point of instantiation within the
3391///        source code.
3392/// \param Instantiation is the declaration whose definition is being
3393///        instantiated. This will be a class of a class temploid
3394///        specialization, or a local enumeration within a function temploid
3395///        specialization.
3396/// \param Pattern The templated declaration from which the instantiation
3397///        occurs.
3398/// \param TemplateArgs The template arguments to be substituted into
3399///        the pattern.
3400///
3401/// \return \c true if an error occurred, \c false otherwise.
3402bool Sema::InstantiateInClassInitializer(
  SourceLocation PointOfInstantiation, FieldDecl *Instantiation,
  FieldDecl *Pattern, const MultiLevelTemplateArgumentList &TemplateArgs) {
// If there is no initializer, we don't need to do anything.
if (!Pattern->hasInClassInitializer())
  return false;

assert(Instantiation->getInClassInitStyle() ==(static_cast <bool> (Instantiation->getInClassInitStyle
() == Pattern->getInClassInitStyle() && "pattern and instantiation disagree about init style"
) ? void (0) : __assert_fail ("Instantiation->getInClassInitStyle() == Pattern->getInClassInitStyle() && \"pattern and instantiation disagree about init style\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3411, __extension__
 __PRETTY_FUNCTION__))
           Pattern->getInClassInitStyle() &&(static_cast <bool> (Instantiation->getInClassInitStyle
() == Pattern->getInClassInitStyle() && "pattern and instantiation disagree about init style"
) ? void (0) : __assert_fail ("Instantiation->getInClassInitStyle() == Pattern->getInClassInitStyle() && \"pattern and instantiation disagree about init style\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3411, __extension__
 __PRETTY_FUNCTION__))
       "pattern and instantiation disagree about init style")(static_cast <bool> (Instantiation->getInClassInitStyle
() == Pattern->getInClassInitStyle() && "pattern and instantiation disagree about init style"
) ? void (0) : __assert_fail ("Instantiation->getInClassInitStyle() == Pattern->getInClassInitStyle() && \"pattern and instantiation disagree about init style\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3411, __extension__
 __PRETTY_FUNCTION__));

// Error out if we haven't parsed the initializer of the pattern yet because
// we are waiting for the closing brace of the outer class.
Expr *OldInit = Pattern->getInClassInitializer();
if (!OldInit) {
  RecordDecl *PatternRD = Pattern->getParent();
  RecordDecl *OutermostClass = PatternRD->getOuterLexicalRecordContext();
  Diag(PointOfInstantiation,
       diag::err_default_member_initializer_not_yet_parsed)
      << OutermostClass << Pattern;
  Diag(Pattern->getEndLoc(),
       diag::note_default_member_initializer_not_yet_parsed);
  Instantiation->setInvalidDecl();
  return true;
}

InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
if (Inst.isInvalid())
  return true;
if (Inst.isAlreadyInstantiating()) {
  // Error out if we hit an instantiation cycle for this initializer.
  Diag(PointOfInstantiation, diag::err_default_member_initializer_cycle)
    << Instantiation;
  return true;
}
PrettyDeclStackTraceEntry CrashInfo(Context, Instantiation, SourceLocation(),
                                    "instantiating default member init");

// Enter the scope of this instantiation. We don't use PushDeclContext because
// we don't have a scope.
ContextRAII SavedContext(*this, Instantiation->getParent());
EnterExpressionEvaluationContext EvalContext(
    *this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated);
ExprEvalContexts.back().DelayedDefaultInitializationContext = {
    PointOfInstantiation, Instantiation, CurContext};

LocalInstantiationScope Scope(*this, true);

// Instantiate the initializer.
ActOnStartCXXInClassMemberInitializer();
CXXThisScopeRAII ThisScope(*this, Instantiation->getParent(), Qualifiers());

ExprResult NewInit = SubstInitializer(OldInit, TemplateArgs,
                                      /*CXXDirectInit=*/false);
Expr *Init = NewInit.get();
assert((!Init || !isa<ParenListExpr>(Init)) && "call-style init in class")(static_cast <bool> ((!Init || !isa<ParenListExpr>
(Init)) && "call-style init in class") ? void (0) : __assert_fail
 ("(!Init || !isa<ParenListExpr>(Init)) && \"call-style init in class\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3457, __extension__
 __PRETTY_FUNCTION__));
ActOnFinishCXXInClassMemberInitializer(
    Instantiation, Init ? Init->getBeginLoc() : SourceLocation(), Init);

if (auto *L = getASTMutationListener())
  L->DefaultMemberInitializerInstantiated(Instantiation);

// Return true if the in-class initializer is still missing.
return !Instantiation->getInClassInitializer();
3466}

3468namespace {
/// A partial specialization whose template arguments have matched
/// a given template-id.
struct PartialSpecMatchResult {
  ClassTemplatePartialSpecializationDecl *Partial;
  TemplateArgumentList *Args;
};
3475}

3477bool Sema::usesPartialOrExplicitSpecialization(
  SourceLocation Loc, ClassTemplateSpecializationDecl *ClassTemplateSpec) {
if (ClassTemplateSpec->getTemplateSpecializationKind() ==
    TSK_ExplicitSpecialization)
  return true;

SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
ClassTemplateSpec->getSpecializedTemplate()
                 ->getPartialSpecializations(PartialSpecs);
for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I) {
  TemplateDeductionInfo Info(Loc);
  if (!DeduceTemplateArguments(PartialSpecs[I],
                               ClassTemplateSpec->getTemplateArgs(), Info))
    return true;
}

return false;
3494}

3496/// Get the instantiation pattern to use to instantiate the definition of a
3497/// given ClassTemplateSpecializationDecl (either the pattern of the primary
3498/// template or of a partial specialization).
3499static ActionResult<CXXRecordDecl *>
3500getPatternForClassTemplateSpecialization(
  Sema &S, SourceLocation PointOfInstantiation,
  ClassTemplateSpecializationDecl *ClassTemplateSpec,
  TemplateSpecializationKind TSK) {
Sema::InstantiatingTemplate Inst(S, PointOfInstantiation, ClassTemplateSpec);
if (Inst.isInvalid())
  return {/*Invalid=*/true};
if (Inst.isAlreadyInstantiating())
  return {/*Invalid=*/false};

llvm::PointerUnion<ClassTemplateDecl *,
                   ClassTemplatePartialSpecializationDecl *>
    Specialized = ClassTemplateSpec->getSpecializedTemplateOrPartial();
if (!Specialized.is<ClassTemplatePartialSpecializationDecl *>()) {
  // Find best matching specialization.
  ClassTemplateDecl *Template = ClassTemplateSpec->getSpecializedTemplate();

  // C++ [temp.class.spec.match]p1:
  //   When a class template is used in a context that requires an
  //   instantiation of the class, it is necessary to determine
  //   whether the instantiation is to be generated using the primary
  //   template or one of the partial specializations. This is done by
  //   matching the template arguments of the class template
  //   specialization with the template argument lists of the partial
  //   specializations.
  typedef PartialSpecMatchResult MatchResult;
  SmallVector<MatchResult, 4> Matched;
  SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
  Template->getPartialSpecializations(PartialSpecs);
  TemplateSpecCandidateSet FailedCandidates(PointOfInstantiation);
  for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I) {
    ClassTemplatePartialSpecializationDecl *Partial = PartialSpecs[I];
    TemplateDeductionInfo Info(FailedCandidates.getLocation());
    if (Sema::TemplateDeductionResult Result = S.DeduceTemplateArguments(
            Partial, ClassTemplateSpec->getTemplateArgs(), Info)) {
      // Store the failed-deduction information for use in diagnostics, later.
      // TODO: Actually use the failed-deduction info?
      FailedCandidates.addCandidate().set(
          DeclAccessPair::make(Template, AS_public), Partial,
          MakeDeductionFailureInfo(S.Context, Result, Info));
      (void)Result;
    } else {
      Matched.push_back(PartialSpecMatchResult());
      Matched.back().Partial = Partial;
      Matched.back().Args = Info.takeCanonical();
    }
  }

  // If we're dealing with a member template where the template parameters
  // have been instantiated, this provides the original template parameters
  // from which the member template's parameters were instantiated.

  if (Matched.size() >= 1) {
    SmallVectorImpl<MatchResult>::iterator Best = Matched.begin();
    if (Matched.size() == 1) {
      //   -- If exactly one matching specialization is found, the
      //      instantiation is generated from that specialization.
      // We don't need to do anything for this.
    } else {
      //   -- If more than one matching specialization is found, the
      //      partial order rules (14.5.4.2) are used to determine
      //      whether one of the specializations is more specialized
      //      than the others. If none of the specializations is more
      //      specialized than all of the other matching
      //      specializations, then the use of the class template is
      //      ambiguous and the program is ill-formed.
      for (SmallVectorImpl<MatchResult>::iterator P = Best + 1,
                                               PEnd = Matched.end();
           P != PEnd; ++P) {
        if (S.getMoreSpecializedPartialSpecialization(
                P->Partial, Best->Partial, PointOfInstantiation) ==
            P->Partial)
          Best = P;
      }

      // Determine if the best partial specialization is more specialized than
      // the others.
      bool Ambiguous = false;
      for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
                                               PEnd = Matched.end();
           P != PEnd; ++P) {
        if (P != Best && S.getMoreSpecializedPartialSpecialization(
                             P->Partial, Best->Partial,
                             PointOfInstantiation) != Best->Partial) {
          Ambiguous = true;
          break;
        }
      }

      if (Ambiguous) {
        // Partial ordering did not produce a clear winner. Complain.
        Inst.Clear();
        ClassTemplateSpec->setInvalidDecl();
        S.Diag(PointOfInstantiation,
               diag::err_partial_spec_ordering_ambiguous)
            << ClassTemplateSpec;

        // Print the matching partial specializations.
        for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
                                                 PEnd = Matched.end();
             P != PEnd; ++P)
          S.Diag(P->Partial->getLocation(), diag::note_partial_spec_match)
              << S.getTemplateArgumentBindingsText(
                     P->Partial->getTemplateParameters(), *P->Args);

        return {/*Invalid=*/true};
      }
    }

    ClassTemplateSpec->setInstantiationOf(Best->Partial, Best->Args);
  } else {
    //   -- If no matches are found, the instantiation is generated
    //      from the primary template.
  }
}

CXXRecordDecl *Pattern = nullptr;
Specialized = ClassTemplateSpec->getSpecializedTemplateOrPartial();
if (auto *PartialSpec =
        Specialized.dyn_cast<ClassTemplatePartialSpecializationDecl *>()) {
  // Instantiate using the best class template partial specialization.
  while (PartialSpec->getInstantiatedFromMember()) {
    // If we've found an explicit specialization of this class template,
    // stop here and use that as the pattern.
    if (PartialSpec->isMemberSpecialization())
      break;

    PartialSpec = PartialSpec->getInstantiatedFromMember();
  }
  Pattern = PartialSpec;
} else {
  ClassTemplateDecl *Template = ClassTemplateSpec->getSpecializedTemplate();
  while (Template->getInstantiatedFromMemberTemplate()) {
    // If we've found an explicit specialization of this class template,
    // stop here and use that as the pattern.
    if (Template->isMemberSpecialization())
      break;

    Template = Template->getInstantiatedFromMemberTemplate();
  }
  Pattern = Template->getTemplatedDecl();
}

return Pattern;
3644}

3646bool Sema::InstantiateClassTemplateSpecialization(
  SourceLocation PointOfInstantiation,
  ClassTemplateSpecializationDecl *ClassTemplateSpec,
  TemplateSpecializationKind TSK, bool Complain) {
// Perform the actual instantiation on the canonical declaration.
ClassTemplateSpec = cast<ClassTemplateSpecializationDecl>(
    ClassTemplateSpec->getCanonicalDecl());
if (ClassTemplateSpec->isInvalidDecl())
  return true;

ActionResult<CXXRecordDecl *> Pattern =
    getPatternForClassTemplateSpecialization(*this, PointOfInstantiation,
                                             ClassTemplateSpec, TSK);
if (!Pattern.isUsable())
  return Pattern.isInvalid();

return InstantiateClass(
    PointOfInstantiation, ClassTemplateSpec, Pattern.get(),
    getTemplateInstantiationArgs(ClassTemplateSpec), TSK, Complain);
3665}

3667/// Instantiates the definitions of all of the member
3668/// of the given class, which is an instantiation of a class template
3669/// or a member class of a template.
3670void
3671Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
                            CXXRecordDecl *Instantiation,
                      const MultiLevelTemplateArgumentList &TemplateArgs,
                            TemplateSpecializationKind TSK) {
// FIXME: We need to notify the ASTMutationListener that we did all of these
// things, in case we have an explicit instantiation definition in a PCM, a
// module, or preamble, and the declaration is in an imported AST.
assert((static_cast <bool> ((TSK == TSK_ExplicitInstantiationDefinition
 || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation
 && Instantiation->isLocalClass())) && "Unexpected template specialization kind!"
) ? void (0) : __assert_fail ("(TSK == TSK_ExplicitInstantiationDefinition || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) && \"Unexpected template specialization kind!\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3682, __extension__
 __PRETTY_FUNCTION__))
    (TSK == TSK_ExplicitInstantiationDefinition ||(static_cast <bool> ((TSK == TSK_ExplicitInstantiationDefinition
 || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation
 && Instantiation->isLocalClass())) && "Unexpected template specialization kind!"
) ? void (0) : __assert_fail ("(TSK == TSK_ExplicitInstantiationDefinition || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) && \"Unexpected template specialization kind!\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3682, __extension__
 __PRETTY_FUNCTION__))
     TSK == TSK_ExplicitInstantiationDeclaration ||(static_cast <bool> ((TSK == TSK_ExplicitInstantiationDefinition
 || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation
 && Instantiation->isLocalClass())) && "Unexpected template specialization kind!"
) ? void (0) : __assert_fail ("(TSK == TSK_ExplicitInstantiationDefinition || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) && \"Unexpected template specialization kind!\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3682, __extension__
 __PRETTY_FUNCTION__))
     (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) &&(static_cast <bool> ((TSK == TSK_ExplicitInstantiationDefinition
 || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation
 && Instantiation->isLocalClass())) && "Unexpected template specialization kind!"
) ? void (0) : __assert_fail ("(TSK == TSK_ExplicitInstantiationDefinition || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) && \"Unexpected template specialization kind!\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3682, __extension__
 __PRETTY_FUNCTION__))
    "Unexpected template specialization kind!")(static_cast <bool> ((TSK == TSK_ExplicitInstantiationDefinition
 || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation
 && Instantiation->isLocalClass())) && "Unexpected template specialization kind!"
) ? void (0) : __assert_fail ("(TSK == TSK_ExplicitInstantiationDefinition || TSK == TSK_ExplicitInstantiationDeclaration || (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) && \"Unexpected template specialization kind!\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3682, __extension__
 __PRETTY_FUNCTION__));
for (auto *D : Instantiation->decls()) {
  bool SuppressNew = false;
  if (auto *Function = dyn_cast<FunctionDecl>(D)) {
    if (FunctionDecl *Pattern =
            Function->getInstantiatedFromMemberFunction()) {

      if (Function->isIneligibleOrNotSelected())
        continue;

      if (Function->getTrailingRequiresClause()) {
        ConstraintSatisfaction Satisfaction;
        if (CheckFunctionConstraints(Function, Satisfaction) ||
            !Satisfaction.IsSatisfied) {
          continue;
        }
      }

      if (Function->hasAttr<ExcludeFromExplicitInstantiationAttr>())
        continue;

      MemberSpecializationInfo *MSInfo =
          Function->getMemberSpecializationInfo();
      assert(MSInfo && "No member specialization information?")(static_cast <bool> (MSInfo && "No member specialization information?"
) ? void (0) : __assert_fail ("MSInfo && \"No member specialization information?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3705, __extension__
 __PRETTY_FUNCTION__));
      if (MSInfo->getTemplateSpecializationKind()
                                               == TSK_ExplicitSpecialization)
        continue;

      if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
                                                 Function,
                                      MSInfo->getTemplateSpecializationKind(),
                                            MSInfo->getPointOfInstantiation(),
                                                 SuppressNew) ||
          SuppressNew)
        continue;

      // C++11 [temp.explicit]p8:
      //   An explicit instantiation definition that names a class template
      //   specialization explicitly instantiates the class template
      //   specialization and is only an explicit instantiation definition
      //   of members whose definition is visible at the point of
      //   instantiation.
      if (TSK == TSK_ExplicitInstantiationDefinition && !Pattern->isDefined())
        continue;

      Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);

      if (Function->isDefined()) {
        // Let the ASTConsumer know that this function has been explicitly
        // instantiated now, and its linkage might have changed.
        Consumer.HandleTopLevelDecl(DeclGroupRef(Function));
      } else if (TSK == TSK_ExplicitInstantiationDefinition) {
        InstantiateFunctionDefinition(PointOfInstantiation, Function);
      } else if (TSK == TSK_ImplicitInstantiation) {
        PendingLocalImplicitInstantiations.push_back(
            std::make_pair(Function, PointOfInstantiation));
      }
    }
  } else if (auto *Var = dyn_cast<VarDecl>(D)) {
    if (isa<VarTemplateSpecializationDecl>(Var))
      continue;

    if (Var->isStaticDataMember()) {
      if (Var->hasAttr<ExcludeFromExplicitInstantiationAttr>())
        continue;

      MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo();
      assert(MSInfo && "No member specialization information?")(static_cast <bool> (MSInfo && "No member specialization information?"
) ? void (0) : __assert_fail ("MSInfo && \"No member specialization information?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3749, __extension__
 __PRETTY_FUNCTION__));
      if (MSInfo->getTemplateSpecializationKind()
                                               == TSK_ExplicitSpecialization)
        continue;

      if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
                                                 Var,
                                      MSInfo->getTemplateSpecializationKind(),
                                            MSInfo->getPointOfInstantiation(),
                                                 SuppressNew) ||
          SuppressNew)
        continue;

      if (TSK == TSK_ExplicitInstantiationDefinition) {
        // C++0x [temp.explicit]p8:
        //   An explicit instantiation definition that names a class template
        //   specialization explicitly instantiates the class template
        //   specialization and is only an explicit instantiation definition
        //   of members whose definition is visible at the point of
        //   instantiation.
        if (!Var->getInstantiatedFromStaticDataMember()->getDefinition())
          continue;

        Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
        InstantiateVariableDefinition(PointOfInstantiation, Var);
      } else {
        Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
      }
    }
  } else if (auto *Record = dyn_cast<CXXRecordDecl>(D)) {
    if (Record->hasAttr<ExcludeFromExplicitInstantiationAttr>())
      continue;

    // Always skip the injected-class-name, along with any
    // redeclarations of nested classes, since both would cause us
    // to try to instantiate the members of a class twice.
    // Skip closure types; they'll get instantiated when we instantiate
    // the corresponding lambda-expression.
    if (Record->isInjectedClassName() || Record->getPreviousDecl() ||
        Record->isLambda())
      continue;

    MemberSpecializationInfo *MSInfo = Record->getMemberSpecializationInfo();
    assert(MSInfo && "No member specialization information?")(static_cast <bool> (MSInfo && "No member specialization information?"
) ? void (0) : __assert_fail ("MSInfo && \"No member specialization information?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3792, __extension__
 __PRETTY_FUNCTION__));

    if (MSInfo->getTemplateSpecializationKind()
                                              == TSK_ExplicitSpecialization)
      continue;

    if (Context.getTargetInfo().getTriple().isOSWindows() &&
        TSK == TSK_ExplicitInstantiationDeclaration) {
      // On Windows, explicit instantiation decl of the outer class doesn't
      // affect the inner class. Typically extern template declarations are
      // used in combination with dll import/export annotations, but those
      // are not propagated from the outer class templates to inner classes.
      // Therefore, do not instantiate inner classes on this platform, so
      // that users don't end up with undefined symbols during linking.
      continue;
    }

    if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
                                               Record,
                                      MSInfo->getTemplateSpecializationKind(),
                                            MSInfo->getPointOfInstantiation(),
                                               SuppressNew) ||
        SuppressNew)
      continue;

    CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
    assert(Pattern && "Missing instantiated-from-template information")(static_cast <bool> (Pattern && "Missing instantiated-from-template information"
) ? void (0) : __assert_fail ("Pattern && \"Missing instantiated-from-template information\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3818, __extension__
 __PRETTY_FUNCTION__));

    if (!Record->getDefinition()) {
      if (!Pattern->getDefinition()) {
        // C++0x [temp.explicit]p8:
        //   An explicit instantiation definition that names a class template
        //   specialization explicitly instantiates the class template
        //   specialization and is only an explicit instantiation definition
        //   of members whose definition is visible at the point of
        //   instantiation.
        if (TSK == TSK_ExplicitInstantiationDeclaration) {
          MSInfo->setTemplateSpecializationKind(TSK);
          MSInfo->setPointOfInstantiation(PointOfInstantiation);
        }

        continue;
      }

      InstantiateClass(PointOfInstantiation, Record, Pattern,
                       TemplateArgs,
                       TSK);
    } else {
      if (TSK == TSK_ExplicitInstantiationDefinition &&
          Record->getTemplateSpecializationKind() ==
              TSK_ExplicitInstantiationDeclaration) {
        Record->setTemplateSpecializationKind(TSK);
        MarkVTableUsed(PointOfInstantiation, Record, true);
      }
    }

    Pattern = cast_or_null<CXXRecordDecl>(Record->getDefinition());
    if (Pattern)
      InstantiateClassMembers(PointOfInstantiation, Pattern, TemplateArgs,
                              TSK);
  } else if (auto *Enum = dyn_cast<EnumDecl>(D)) {
    MemberSpecializationInfo *MSInfo = Enum->getMemberSpecializationInfo();
    assert(MSInfo && "No member specialization information?")(static_cast <bool> (MSInfo && "No member specialization information?"
) ? void (0) : __assert_fail ("MSInfo && \"No member specialization information?\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3854, __extension__
 __PRETTY_FUNCTION__));

    if (MSInfo->getTemplateSpecializationKind()
          == TSK_ExplicitSpecialization)
      continue;

    if (CheckSpecializationInstantiationRedecl(
          PointOfInstantiation, TSK, Enum,
          MSInfo->getTemplateSpecializationKind(),
          MSInfo->getPointOfInstantiation(), SuppressNew) ||
        SuppressNew)
      continue;

    if (Enum->getDefinition())
      continue;

    EnumDecl *Pattern = Enum->getTemplateInstantiationPattern();
    assert(Pattern && "Missing instantiated-from-template information")(static_cast <bool> (Pattern && "Missing instantiated-from-template information"
) ? void (0) : __assert_fail ("Pattern && \"Missing instantiated-from-template information\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3871, __extension__
 __PRETTY_FUNCTION__));

    if (TSK == TSK_ExplicitInstantiationDefinition) {
      if (!Pattern->getDefinition())
        continue;

      InstantiateEnum(PointOfInstantiation, Enum, Pattern, TemplateArgs, TSK);
    } else {
      MSInfo->setTemplateSpecializationKind(TSK);
      MSInfo->setPointOfInstantiation(PointOfInstantiation);
    }
  } else if (auto *Field = dyn_cast<FieldDecl>(D)) {
    // No need to instantiate in-class initializers during explicit
    // instantiation.
    if (Field->hasInClassInitializer() && TSK == TSK_ImplicitInstantiation) {
      CXXRecordDecl *ClassPattern =
          Instantiation->getTemplateInstantiationPattern();
      DeclContext::lookup_result Lookup =
          ClassPattern->lookup(Field->getDeclName());
      FieldDecl *Pattern = Lookup.find_first<FieldDecl>();
      assert(Pattern)(static_cast <bool> (Pattern) ? void (0) : __assert_fail
 ("Pattern", "clang/lib/Sema/SemaTemplateInstantiate.cpp", 3891
, __extension__ __PRETTY_FUNCTION__));
      InstantiateInClassInitializer(PointOfInstantiation, Field, Pattern,
                                    TemplateArgs);
    }
  }
}
3897}

3899/// Instantiate the definitions of all of the members of the
3900/// given class template specialization, which was named as part of an
3901/// explicit instantiation.
3902void
3903Sema::InstantiateClassTemplateSpecializationMembers(
                                         SourceLocation PointOfInstantiation,
                          ClassTemplateSpecializationDecl *ClassTemplateSpec,
                                             TemplateSpecializationKind TSK) {
// C++0x [temp.explicit]p7:
//   An explicit instantiation that names a class template
//   specialization is an explicit instantion of the same kind
//   (declaration or definition) of each of its members (not
//   including members inherited from base classes) that has not
//   been previously explicitly specialized in the translation unit
//   containing the explicit instantiation, except as described
//   below.
InstantiateClassMembers(PointOfInstantiation, ClassTemplateSpec,
                        getTemplateInstantiationArgs(ClassTemplateSpec),
                        TSK);
3918}

3920StmtResult
3921Sema::SubstStmt(Stmt *S, const MultiLevelTemplateArgumentList &TemplateArgs) {
if (!S)
  return S;

TemplateInstantiator Instantiator(*this, TemplateArgs,
                                  SourceLocation(),
                                  DeclarationName());
return Instantiator.TransformStmt(S);
3929}

3931bool Sema::SubstTemplateArguments(
  ArrayRef<TemplateArgumentLoc> Args,
  const MultiLevelTemplateArgumentList &TemplateArgs,
  TemplateArgumentListInfo &Out) {
TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
                                  DeclarationName());
return Instantiator.TransformTemplateArguments(Args.begin(), Args.end(), Out);
3938}

3940ExprResult
3941Sema::SubstExpr(Expr *E, const MultiLevelTemplateArgumentList &TemplateArgs) {
if (!E)
  return E;

TemplateInstantiator Instantiator(*this, TemplateArgs,
                                  SourceLocation(),
                                  DeclarationName());
return Instantiator.TransformExpr(E);
3949}

3951ExprResult
3952Sema::SubstConstraintExpr(Expr *E,
                        const MultiLevelTemplateArgumentList &TemplateArgs) {
if (!E)
  return E;

// This is where we need to make sure we 'know' constraint checking needs to
// happen.
TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
                                  DeclarationName());
return Instantiator.TransformExpr(E);
3962}

3964ExprResult Sema::SubstInitializer(Expr *Init,
                        const MultiLevelTemplateArgumentList &TemplateArgs,
                        bool CXXDirectInit) {
TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
                                  DeclarationName());
return Instantiator.TransformInitializer(Init, CXXDirectInit);
3970}

3972bool Sema::SubstExprs(ArrayRef<Expr *> Exprs, bool IsCall,
                    const MultiLevelTemplateArgumentList &TemplateArgs,
                    SmallVectorImpl<Expr *> &Outputs) {
if (Exprs.empty())
  return false;

TemplateInstantiator Instantiator(*this, TemplateArgs,
                                  SourceLocation(),
                                  DeclarationName());
return Instantiator.TransformExprs(Exprs.data(), Exprs.size(),
                                   IsCall, Outputs);
3983}

3985NestedNameSpecifierLoc
3986Sema::SubstNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,
                      const MultiLevelTemplateArgumentList &TemplateArgs) {
if (!NNS)
  return NestedNameSpecifierLoc();

TemplateInstantiator Instantiator(*this, TemplateArgs, NNS.getBeginLoc(),
                                  DeclarationName());
return Instantiator.TransformNestedNameSpecifierLoc(NNS);
3994}

3996/// Do template substitution on declaration name info.
3997DeclarationNameInfo
3998Sema::SubstDeclarationNameInfo(const DeclarationNameInfo &NameInfo,
                       const MultiLevelTemplateArgumentList &TemplateArgs) {
TemplateInstantiator Instantiator(*this, TemplateArgs, NameInfo.getLoc(),
                                  NameInfo.getName());
return Instantiator.TransformDeclarationNameInfo(NameInfo);
4003}

4005TemplateName
4006Sema::SubstTemplateName(NestedNameSpecifierLoc QualifierLoc,
                      TemplateName Name, SourceLocation Loc,
                      const MultiLevelTemplateArgumentList &TemplateArgs) {
TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
                                  DeclarationName());
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
return Instantiator.TransformTemplateName(SS, Name, Loc);
4014}

4016static const Decl *getCanonicalParmVarDecl(const Decl *D) {
// When storing ParmVarDecls in the local instantiation scope, we always
// want to use the ParmVarDecl from the canonical function declaration,
// since the map is then valid for any redeclaration or definition of that
// function.
if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(D)) {
  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(PV->getDeclContext())) {
    unsigned i = PV->getFunctionScopeIndex();
    // This parameter might be from a freestanding function type within the
    // function and isn't necessarily referring to one of FD's parameters.
    if (i < FD->getNumParams() && FD->getParamDecl(i) == PV)
      return FD->getCanonicalDecl()->getParamDecl(i);
  }
}
return D;
4031}


4034llvm::PointerUnion<Decl *, LocalInstantiationScope::DeclArgumentPack *> *
4035LocalInstantiationScope::findInstantiationOf(const Decl *D) {
D = getCanonicalParmVarDecl(D);
for (LocalInstantiationScope *Current = this; Current;
     Current = Current->Outer) {

  // Check if we found something within this scope.
  const Decl *CheckD = D;
  do {
    LocalDeclsMap::iterator Found = Current->LocalDecls.find(CheckD);
    if (Found != Current->LocalDecls.end())
      return &Found->second;

    // If this is a tag declaration, it's possible that we need to look for
    // a previous declaration.
    if (const TagDecl *Tag = dyn_cast<TagDecl>(CheckD))
      CheckD = Tag->getPreviousDecl();
    else
      CheckD = nullptr;
  } while (CheckD);

  // If we aren't combined with our outer scope, we're done.
  if (!Current->CombineWithOuterScope)
    break;
}

// If we're performing a partial substitution during template argument
// deduction, we may not have values for template parameters yet.
if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
    isa<TemplateTemplateParmDecl>(D))
  return nullptr;

// Local types referenced prior to definition may require instantiation.
if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D))
  if (RD->isLocalClass())
    return nullptr;

// Enumeration types referenced prior to definition may appear as a result of
// error recovery.
if (isa<EnumDecl>(D))
  return nullptr;

// Materialized typedefs/type alias for implicit deduction guides may require
// instantiation.
if (isa<TypedefNameDecl>(D) &&
    isa<CXXDeductionGuideDecl>(D->getDeclContext()))
  return nullptr;

// If we didn't find the decl, then we either have a sema bug, or we have a
// forward reference to a label declaration.  Return null to indicate that
// we have an uninstantiated label.
assert(isa<LabelDecl>(D) && "declaration not instantiated in this scope")(static_cast <bool> (isa<LabelDecl>(D) &&
 "declaration not instantiated in this scope") ? void (0) : __assert_fail
 ("isa<LabelDecl>(D) && \"declaration not instantiated in this scope\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4085, __extension__
 __PRETTY_FUNCTION__));
return nullptr;
4087}

4089void LocalInstantiationScope::InstantiatedLocal(const Decl *D, Decl *Inst) {
D = getCanonicalParmVarDecl(D);
llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
if (Stored.isNull()) {
4093#ifndef NDEBUG
  // It should not be present in any surrounding scope either.
  LocalInstantiationScope *Current = this;
  while (Current->CombineWithOuterScope && Current->Outer) {
    Current = Current->Outer;
    assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&(static_cast <bool> (Current->LocalDecls.find(D) == Current
->LocalDecls.end() && "Instantiated local in inner and outer scopes"
) ? void (0) : __assert_fail ("Current->LocalDecls.find(D) == Current->LocalDecls.end() && \"Instantiated local in inner and outer scopes\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4099, __extension__
 __PRETTY_FUNCTION__))
           "Instantiated local in inner and outer scopes")(static_cast <bool> (Current->LocalDecls.find(D) == Current
->LocalDecls.end() && "Instantiated local in inner and outer scopes"
) ? void (0) : __assert_fail ("Current->LocalDecls.find(D) == Current->LocalDecls.end() && \"Instantiated local in inner and outer scopes\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4099, __extension__
 __PRETTY_FUNCTION__));
  }
4101#endif
  Stored = Inst;
} else if (DeclArgumentPack *Pack = Stored.dyn_cast<DeclArgumentPack *>()) {
  Pack->push_back(cast<VarDecl>(Inst));
} else {
  assert(Stored.get<Decl *>() == Inst && "Already instantiated this local")(static_cast <bool> (Stored.get<Decl *>() == Inst
 && "Already instantiated this local") ? void (0) : __assert_fail
 ("Stored.get<Decl *>() == Inst && \"Already instantiated this local\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4106, __extension__
 __PRETTY_FUNCTION__));
}
4108}

4110void LocalInstantiationScope::InstantiatedLocalPackArg(const Decl *D,
                                                     VarDecl *Inst) {
D = getCanonicalParmVarDecl(D);
DeclArgumentPack *Pack = LocalDecls[D].get<DeclArgumentPack *>();
Pack->push_back(Inst);
4115}

4117void LocalInstantiationScope::MakeInstantiatedLocalArgPack(const Decl *D) {
4118#ifndef NDEBUG
// This should be the first time we've been told about this decl.
for (LocalInstantiationScope *Current = this;
     Current && Current->CombineWithOuterScope; Current = Current->Outer)
  assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&(static_cast <bool> (Current->LocalDecls.find(D) == Current
->LocalDecls.end() && "Creating local pack after instantiation of local"
) ? void (0) : __assert_fail ("Current->LocalDecls.find(D) == Current->LocalDecls.end() && \"Creating local pack after instantiation of local\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4123, __extension__
 __PRETTY_FUNCTION__))
         "Creating local pack after instantiation of local")(static_cast <bool> (Current->LocalDecls.find(D) == Current
->LocalDecls.end() && "Creating local pack after instantiation of local"
) ? void (0) : __assert_fail ("Current->LocalDecls.find(D) == Current->LocalDecls.end() && \"Creating local pack after instantiation of local\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4123, __extension__
 __PRETTY_FUNCTION__));
4124#endif

D = getCanonicalParmVarDecl(D);
llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
DeclArgumentPack *Pack = new DeclArgumentPack;
Stored = Pack;
ArgumentPacks.push_back(Pack);
4131}

4133bool LocalInstantiationScope::isLocalPackExpansion(const Decl *D) {
for (DeclArgumentPack *Pack : ArgumentPacks)
  if (llvm::is_contained(*Pack, D))
    return true;
return false;
4138}

4140void LocalInstantiationScope::SetPartiallySubstitutedPack(NamedDecl *Pack,
                                        const TemplateArgument *ExplicitArgs,
                                                  unsigned NumExplicitArgs) {
assert((!PartiallySubstitutedPack || PartiallySubstitutedPack == Pack) &&(static_cast <bool> ((!PartiallySubstitutedPack || PartiallySubstitutedPack
 == Pack) && "Already have a partially-substituted pack"
) ? void (0) : __assert_fail ("(!PartiallySubstitutedPack || PartiallySubstitutedPack == Pack) && \"Already have a partially-substituted pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4144, __extension__
 __PRETTY_FUNCTION__))
       "Already have a partially-substituted pack")(static_cast <bool> ((!PartiallySubstitutedPack || PartiallySubstitutedPack
 == Pack) && "Already have a partially-substituted pack"
) ? void (0) : __assert_fail ("(!PartiallySubstitutedPack || PartiallySubstitutedPack == Pack) && \"Already have a partially-substituted pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4144, __extension__
 __PRETTY_FUNCTION__));
assert((!PartiallySubstitutedPack(static_cast <bool> ((!PartiallySubstitutedPack || NumArgsInPartiallySubstitutedPack
 == NumExplicitArgs) && "Wrong number of arguments in partially-substituted pack"
) ? void (0) : __assert_fail ("(!PartiallySubstitutedPack || NumArgsInPartiallySubstitutedPack == NumExplicitArgs) && \"Wrong number of arguments in partially-substituted pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4147, __extension__
 __PRETTY_FUNCTION__))
        || NumArgsInPartiallySubstitutedPack == NumExplicitArgs) &&(static_cast <bool> ((!PartiallySubstitutedPack || NumArgsInPartiallySubstitutedPack
 == NumExplicitArgs) && "Wrong number of arguments in partially-substituted pack"
) ? void (0) : __assert_fail ("(!PartiallySubstitutedPack || NumArgsInPartiallySubstitutedPack == NumExplicitArgs) && \"Wrong number of arguments in partially-substituted pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4147, __extension__
 __PRETTY_FUNCTION__))
       "Wrong number of arguments in partially-substituted pack")(static_cast <bool> ((!PartiallySubstitutedPack || NumArgsInPartiallySubstitutedPack
 == NumExplicitArgs) && "Wrong number of arguments in partially-substituted pack"
) ? void (0) : __assert_fail ("(!PartiallySubstitutedPack || NumArgsInPartiallySubstitutedPack == NumExplicitArgs) && \"Wrong number of arguments in partially-substituted pack\""
, "clang/lib/Sema/SemaTemplateInstantiate.cpp", 4147, __extension__
 __PRETTY_FUNCTION__));
PartiallySubstitutedPack = Pack;
ArgsInPartiallySubstitutedPack = ExplicitArgs;
NumArgsInPartiallySubstitutedPack = NumExplicitArgs;
4151}

4153NamedDecl *LocalInstantiationScope::getPartiallySubstitutedPack(
                                       const TemplateArgument **ExplicitArgs,
                                            unsigned *NumExplicitArgs) const {
if (ExplicitArgs)
  *ExplicitArgs = nullptr;
if (NumExplicitArgs)
  *NumExplicitArgs = 0;

for (const LocalInstantiationScope *Current = this; Current;
     Current = Current->Outer) {
  if (Current->PartiallySubstitutedPack) {
    if (ExplicitArgs)
      *ExplicitArgs = Current->ArgsInPartiallySubstitutedPack;
    if (NumExplicitArgs)
      *NumExplicitArgs = Current->NumArgsInPartiallySubstitutedPack;

    return Current->PartiallySubstitutedPack;
  }

  if (!Current->CombineWithOuterScope)
    break;
}

return nullptr;
4177}

←

/build/source/clang/lib/Sema/TreeTransform.h

1	//===------- TreeTransform.h - Semantic Tree Transformation ------ 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	// This file implements a semantic tree transformation that takes a given
9	// AST and rebuilds it, possibly transforming some nodes in the process.
10	//
11	//===----------------------------------------------------------------------===//
12
13	#ifndef LLVM_CLANG_LIB_SEMA_TREETRANSFORM_H
14	#define LLVM_CLANG_LIB_SEMA_TREETRANSFORM_H
15
16	#include "CoroutineStmtBuilder.h"
17	#include "TypeLocBuilder.h"
18	#include "clang/AST/Decl.h"
19	#include "clang/AST/DeclObjC.h"
20	#include "clang/AST/DeclTemplate.h"
21	#include "clang/AST/Expr.h"
22	#include "clang/AST/ExprConcepts.h"
23	#include "clang/AST/ExprCXX.h"
24	#include "clang/AST/ExprObjC.h"
25	#include "clang/AST/ExprOpenMP.h"
26	#include "clang/AST/OpenMPClause.h"
27	#include "clang/AST/Stmt.h"
28	#include "clang/AST/StmtCXX.h"
29	#include "clang/AST/StmtObjC.h"
30	#include "clang/AST/StmtOpenMP.h"
31	#include "clang/Basic/DiagnosticParse.h"
32	#include "clang/Basic/OpenMPKinds.h"
33	#include "clang/Sema/Designator.h"
34	#include "clang/Sema/Lookup.h"
35	#include "clang/Sema/Ownership.h"
36	#include "clang/Sema/ParsedTemplate.h"
37	#include "clang/Sema/ScopeInfo.h"
38	#include "clang/Sema/SemaDiagnostic.h"
39	#include "clang/Sema/SemaInternal.h"
40	#include "llvm/ADT/ArrayRef.h"
41	#include "llvm/Support/ErrorHandling.h"
42	#include <algorithm>
43	#include <optional>
44
45	using namespace llvm::omp;
46
47	namespace clang {
48	using namespace sema;
49
50	/// A semantic tree transformation that allows one to transform one
51	/// abstract syntax tree into another.
52	///
53	/// A new tree transformation is defined by creating a new subclass \c X of
54	/// \c TreeTransform<X> and then overriding certain operations to provide
55	/// behavior specific to that transformation. For example, template
56	/// instantiation is implemented as a tree transformation where the
57	/// transformation of TemplateTypeParmType nodes involves substituting the
58	/// template arguments for their corresponding template parameters; a similar
59	/// transformation is performed for non-type template parameters and
60	/// template template parameters.
61	///
62	/// This tree-transformation template uses static polymorphism to allow
63	/// subclasses to customize any of its operations. Thus, a subclass can
64	/// override any of the transformation or rebuild operators by providing an
65	/// operation with the same signature as the default implementation. The
66	/// overriding function should not be virtual.
67	///
68	/// Semantic tree transformations are split into two stages, either of which
69	/// can be replaced by a subclass. The "transform" step transforms an AST node
70	/// or the parts of an AST node using the various transformation functions,
71	/// then passes the pieces on to the "rebuild" step, which constructs a new AST
72	/// node of the appropriate kind from the pieces. The default transformation
73	/// routines recursively transform the operands to composite AST nodes (e.g.,
74	/// the pointee type of a PointerType node) and, if any of those operand nodes
75	/// were changed by the transformation, invokes the rebuild operation to create
76	/// a new AST node.
77	///
78	/// Subclasses can customize the transformation at various levels. The
79	/// most coarse-grained transformations involve replacing TransformType(),
80	/// TransformExpr(), TransformDecl(), TransformNestedNameSpecifierLoc(),
81	/// TransformTemplateName(), or TransformTemplateArgument() with entirely
82	/// new implementations.
83	///
84	/// For more fine-grained transformations, subclasses can replace any of the
85	/// \c TransformXXX functions (where XXX is the name of an AST node, e.g.,
86	/// PointerType, StmtExpr) to alter the transformation. As mentioned previously,
87	/// replacing TransformTemplateTypeParmType() allows template instantiation
88	/// to substitute template arguments for their corresponding template
89	/// parameters. Additionally, subclasses can override the \c RebuildXXX
90	/// functions to control how AST nodes are rebuilt when their operands change.
91	/// By default, \c TreeTransform will invoke semantic analysis to rebuild
92	/// AST nodes. However, certain other tree transformations (e.g, cloning) may
93	/// be able to use more efficient rebuild steps.
94	///
95	/// There are a handful of other functions that can be overridden, allowing one
96	/// to avoid traversing nodes that don't need any transformation
97	/// (\c AlreadyTransformed()), force rebuilding AST nodes even when their
98	/// operands have not changed (\c AlwaysRebuild()), and customize the
99	/// default locations and entity names used for type-checking
100	/// (\c getBaseLocation(), \c getBaseEntity()).
101	template<typename Derived>
102	class TreeTransform {
103	/// Private RAII object that helps us forget and then re-remember
104	/// the template argument corresponding to a partially-substituted parameter
105	/// pack.
106	class ForgetPartiallySubstitutedPackRAII {
107	Derived &Self;
108	TemplateArgument Old;
109
110	public:
111	ForgetPartiallySubstitutedPackRAII(Derived &Self) : Self(Self) {
112	Old = Self.ForgetPartiallySubstitutedPack();
113	}
114
115	~ForgetPartiallySubstitutedPackRAII() {
116	Self.RememberPartiallySubstitutedPack(Old);
117	}
118	};
119
120	protected:
121	Sema &SemaRef;
122
123	/// The set of local declarations that have been transformed, for
124	/// cases where we are forced to build new declarations within the transformer
125	/// rather than in the subclass (e.g., lambda closure types).
126	llvm::DenseMap<Decl , Decl > TransformedLocalDecls;
127
128	public:
129	/// Initializes a new tree transformer.
130	TreeTransform(Sema &SemaRef) : SemaRef(SemaRef) { }
131
132	/// Retrieves a reference to the derived class.
133	Derived &getDerived() { return static_cast<Derived&>(*this); }
134
135	/// Retrieves a reference to the derived class.
136	const Derived &getDerived() const {
137	return static_cast<const Derived&>(*this);
138	}
139
140	static inline ExprResult Owned(Expr *E) { return E; }
141	static inline StmtResult Owned(Stmt *S) { return S; }
142
143	/// Retrieves a reference to the semantic analysis object used for
144	/// this tree transform.
145	Sema &getSema() const { return SemaRef; }
146
147	/// Whether the transformation should always rebuild AST nodes, even
148	/// if none of the children have changed.
149	///
150	/// Subclasses may override this function to specify when the transformation
151	/// should rebuild all AST nodes.
152	///
153	/// We must always rebuild all AST nodes when performing variadic template
154	/// pack expansion, in order to avoid violating the AST invariant that each
155	/// statement node appears at most once in its containing declaration.
156	bool AlwaysRebuild() { return SemaRef.ArgumentPackSubstitutionIndex != -1; }
157
158	/// Whether the transformation is forming an expression or statement that
159	/// replaces the original. In this case, we'll reuse mangling numbers from
160	/// existing lambdas.
161	bool ReplacingOriginal() { return false; }
162
163	/// Wether CXXConstructExpr can be skipped when they are implicit.
164	/// They will be reconstructed when used if needed.
165	/// This is useful when the user that cause rebuilding of the
166	/// CXXConstructExpr is outside of the expression at which the TreeTransform
167	/// started.
168	bool AllowSkippingCXXConstructExpr() { return true; }
169
170	/// Returns the location of the entity being transformed, if that
171	/// information was not available elsewhere in the AST.
172	///
173	/// By default, returns no source-location information. Subclasses can
174	/// provide an alternative implementation that provides better location
175	/// information.
176	SourceLocation getBaseLocation() { return SourceLocation(); }
177
178	/// Returns the name of the entity being transformed, if that
179	/// information was not available elsewhere in the AST.
180	///
181	/// By default, returns an empty name. Subclasses can provide an alternative
182	/// implementation with a more precise name.
183	DeclarationName getBaseEntity() { return DeclarationName(); }
184
185	/// Sets the "base" location and entity when that
186	/// information is known based on another transformation.
187	///
188	/// By default, the source location and entity are ignored. Subclasses can
189	/// override this function to provide a customized implementation.
190	void setBase(SourceLocation Loc, DeclarationName Entity) { }
191
192	/// RAII object that temporarily sets the base location and entity
193	/// used for reporting diagnostics in types.
194	class TemporaryBase {
195	TreeTransform &Self;
196	SourceLocation OldLocation;
197	DeclarationName OldEntity;
198
199	public:
200	TemporaryBase(TreeTransform &Self, SourceLocation Location,
201	DeclarationName Entity) : Self(Self) {
202	OldLocation = Self.getDerived().getBaseLocation();
203	OldEntity = Self.getDerived().getBaseEntity();
204
205	if (Location.isValid())
206	Self.getDerived().setBase(Location, Entity);
207	}
208
209	~TemporaryBase() {
210	Self.getDerived().setBase(OldLocation, OldEntity);
211	}
212	};
213
214	/// Determine whether the given type \p T has already been
215	/// transformed.
216	///
217	/// Subclasses can provide an alternative implementation of this routine
218	/// to short-circuit evaluation when it is known that a given type will
219	/// not change. For example, template instantiation need not traverse
220	/// non-dependent types.
221	bool AlreadyTransformed(QualType T) {
222	return T.isNull();
223	}
224
225	/// Transform a template parameter depth level.
226	///
227	/// During a transformation that transforms template parameters, this maps
228	/// an old template parameter depth to a new depth.
229	unsigned TransformTemplateDepth(unsigned Depth) {
230	return Depth;
231	}
232
233	/// Determine whether the given call argument should be dropped, e.g.,
234	/// because it is a default argument.
235	///
236	/// Subclasses can provide an alternative implementation of this routine to
237	/// determine which kinds of call arguments get dropped. By default,
238	/// CXXDefaultArgument nodes are dropped (prior to transformation).
239	bool DropCallArgument(Expr *E) {
240	return E->isDefaultArgument();
241	}
242
243	/// Determine whether we should expand a pack expansion with the
244	/// given set of parameter packs into separate arguments by repeatedly
245	/// transforming the pattern.
246	///
247	/// By default, the transformer never tries to expand pack expansions.
248	/// Subclasses can override this routine to provide different behavior.
249	///
250	/// \param EllipsisLoc The location of the ellipsis that identifies the
251	/// pack expansion.
252	///
253	/// \param PatternRange The source range that covers the entire pattern of
254	/// the pack expansion.
255	///
256	/// \param Unexpanded The set of unexpanded parameter packs within the
257	/// pattern.
258	///
259	/// \param ShouldExpand Will be set to \c true if the transformer should
260	/// expand the corresponding pack expansions into separate arguments. When
261	/// set, \c NumExpansions must also be set.
262	///
263	/// \param RetainExpansion Whether the caller should add an unexpanded
264	/// pack expansion after all of the expanded arguments. This is used
265	/// when extending explicitly-specified template argument packs per
266	/// C++0x [temp.arg.explicit]p9.
267	///
268	/// \param NumExpansions The number of separate arguments that will be in
269	/// the expanded form of the corresponding pack expansion. This is both an
270	/// input and an output parameter, which can be set by the caller if the
271	/// number of expansions is known a priori (e.g., due to a prior substitution)
272	/// and will be set by the callee when the number of expansions is known.
273	/// The callee must set this value when \c ShouldExpand is \c true; it may
274	/// set this value in other cases.
275	///
276	/// \returns true if an error occurred (e.g., because the parameter packs
277	/// are to be instantiated with arguments of different lengths), false
278	/// otherwise. If false, \c ShouldExpand (and possibly \c NumExpansions)
279	/// must be set.
280	bool TryExpandParameterPacks(SourceLocation EllipsisLoc,
281	SourceRange PatternRange,
282	ArrayRef<UnexpandedParameterPack> Unexpanded,
283	bool &ShouldExpand, bool &RetainExpansion,
284	std::optional<unsigned> &NumExpansions) {
285	ShouldExpand = false;
286	return false;
287	}
288
289	/// "Forget" about the partially-substituted pack template argument,
290	/// when performing an instantiation that must preserve the parameter pack
291	/// use.
292	///
293	/// This routine is meant to be overridden by the template instantiator.
294	TemplateArgument ForgetPartiallySubstitutedPack() {
295	return TemplateArgument();
296	}
297
298	/// "Remember" the partially-substituted pack template argument
299	/// after performing an instantiation that must preserve the parameter pack
300	/// use.
301	///
302	/// This routine is meant to be overridden by the template instantiator.
303	void RememberPartiallySubstitutedPack(TemplateArgument Arg) { }
304
305	/// Note to the derived class when a function parameter pack is
306	/// being expanded.
307	void ExpandingFunctionParameterPack(ParmVarDecl *Pack) { }
308
309	/// Transforms the given type into another type.
310	///
311	/// By default, this routine transforms a type by creating a
312	/// TypeSourceInfo for it and delegating to the appropriate
313	/// function. This is expensive, but we don't mind, because
314	/// this method is deprecated anyway; all users should be
315	/// switched to storing TypeSourceInfos.
316	///
317	/// \returns the transformed type.
318	QualType TransformType(QualType T);
319
320	/// Transforms the given type-with-location into a new
321	/// type-with-location.
322	///
323	/// By default, this routine transforms a type by delegating to the
324	/// appropriate TransformXXXType to build a new type. Subclasses
325	/// may override this function (to take over all type
326	/// transformations) or some set of the TransformXXXType functions
327	/// to alter the transformation.
328	TypeSourceInfo TransformType(TypeSourceInfo DI);
329
330	/// Transform the given type-with-location into a new
331	/// type, collecting location information in the given builder
332	/// as necessary.
333	///
334	QualType TransformType(TypeLocBuilder &TLB, TypeLoc TL);
335
336	/// Transform a type that is permitted to produce a
337	/// DeducedTemplateSpecializationType.
338	///
339	/// This is used in the (relatively rare) contexts where it is acceptable
340	/// for transformation to produce a class template type with deduced
341	/// template arguments.
342	/// @{
343	QualType TransformTypeWithDeducedTST(QualType T);
344	TypeSourceInfo TransformTypeWithDeducedTST(TypeSourceInfo DI);
345	/// @}
346
347	/// The reason why the value of a statement is not discarded, if any.
348	enum StmtDiscardKind {
349	SDK_Discarded,
350	SDK_NotDiscarded,
351	SDK_StmtExprResult,
352	};
353
354	/// Transform the given statement.
355	///
356	/// By default, this routine transforms a statement by delegating to the
357	/// appropriate TransformXXXStmt function to transform a specific kind of
358	/// statement or the TransformExpr() function to transform an expression.
359	/// Subclasses may override this function to transform statements using some
360	/// other mechanism.
361	///
362	/// \returns the transformed statement.
363	StmtResult TransformStmt(Stmt *S, StmtDiscardKind SDK = SDK_Discarded);
364
365	/// Transform the given statement.
366	///
367	/// By default, this routine transforms a statement by delegating to the
368	/// appropriate TransformOMPXXXClause function to transform a specific kind
369	/// of clause. Subclasses may override this function to transform statements
370	/// using some other mechanism.
371	///
372	/// \returns the transformed OpenMP clause.
373	OMPClause TransformOMPClause(OMPClause S);
374
375	/// Transform the given attribute.
376	///
377	/// By default, this routine transforms a statement by delegating to the
378	/// appropriate TransformXXXAttr function to transform a specific kind
379	/// of attribute. Subclasses may override this function to transform
380	/// attributed statements/types using some other mechanism.
381	///
382	/// \returns the transformed attribute
383	const Attr TransformAttr(const Attr S);
384
385	// Transform the given statement attribute.
386	//
387	// Delegates to the appropriate TransformXXXAttr function to transform a
388	// specific kind of statement attribute. Unlike the non-statement taking
389	// version of this, this implements all attributes, not just pragmas.
390	const Attr TransformStmtAttr(const Stmt OrigS, const Stmt *InstS,
391	const Attr *A);
392
393	// Transform the specified attribute.
394	//
395	// Subclasses should override the transformation of attributes with a pragma
396	// spelling to transform expressions stored within the attribute.
397	//
398	// \returns the transformed attribute.
399	#define ATTR(X) \
400	const X##Attr Transform##X##Attr(const X##Attr R) { return R; }
401	#include "clang/Basic/AttrList.inc"
402
403	// Transform the specified attribute.
404	//
405	// Subclasses should override the transformation of attributes to do
406	// transformation and checking of statement attributes. By default, this
407	// delegates to the non-statement taking version.
408	//
409	// \returns the transformed attribute.
410	#define ATTR(X) \
411	const X##Attr TransformStmt##X##Attr(const Stmt , const Stmt *, \
412	const X##Attr *A) { \
413	return getDerived().Transform##X##Attr(A); \
414	}
415	#include "clang/Basic/AttrList.inc"
416
417	/// Transform the given expression.
418	///
419	/// By default, this routine transforms an expression by delegating to the
420	/// appropriate TransformXXXExpr function to build a new expression.
421	/// Subclasses may override this function to transform expressions using some
422	/// other mechanism.
423	///
424	/// \returns the transformed expression.
425	ExprResult TransformExpr(Expr *E);
426
427	/// Transform the given initializer.
428	///
429	/// By default, this routine transforms an initializer by stripping off the
430	/// semantic nodes added by initialization, then passing the result to
431	/// TransformExpr or TransformExprs.
432	///
433	/// \returns the transformed initializer.
434	ExprResult TransformInitializer(Expr *Init, bool NotCopyInit);
435
436	/// Transform the given list of expressions.
437	///
438	/// This routine transforms a list of expressions by invoking
439	/// \c TransformExpr() for each subexpression. However, it also provides
440	/// support for variadic templates by expanding any pack expansions (if the
441	/// derived class permits such expansion) along the way. When pack expansions
442	/// are present, the number of outputs may not equal the number of inputs.
443	///
444	/// \param Inputs The set of expressions to be transformed.
445	///
446	/// \param NumInputs The number of expressions in \c Inputs.
447	///
448	/// \param IsCall If \c true, then this transform is being performed on
449	/// function-call arguments, and any arguments that should be dropped, will
450	/// be.
451	///
452	/// \param Outputs The transformed input expressions will be added to this
453	/// vector.
454	///
455	/// \param ArgChanged If non-NULL, will be set \c true if any argument changed
456	/// due to transformation.
457	///
458	/// \returns true if an error occurred, false otherwise.
459	bool TransformExprs(Expr const Inputs, unsigned NumInputs, bool IsCall,
460	SmallVectorImpl<Expr *> &Outputs,
461	bool *ArgChanged = nullptr);
462
463	/// Transform the given declaration, which is referenced from a type
464	/// or expression.
465	///
466	/// By default, acts as the identity function on declarations, unless the
467	/// transformer has had to transform the declaration itself. Subclasses
468	/// may override this function to provide alternate behavior.
469	Decl TransformDecl(SourceLocation Loc, Decl D) {
470	llvm::DenseMap<Decl , Decl >::iterator Known
471	= TransformedLocalDecls.find(D);
472	if (Known != TransformedLocalDecls.end())
473	return Known->second;
474
475	return D;
476	}
477
478	/// Transform the specified condition.
479	///
480	/// By default, this transforms the variable and expression and rebuilds
481	/// the condition.
482	Sema::ConditionResult TransformCondition(SourceLocation Loc, VarDecl *Var,
483	Expr *Expr,
484	Sema::ConditionKind Kind);
485
486	/// Transform the attributes associated with the given declaration and
487	/// place them on the new declaration.
488	///
489	/// By default, this operation does nothing. Subclasses may override this
490	/// behavior to transform attributes.
491	void transformAttrs(Decl Old, Decl New) { }
492
493	/// Note that a local declaration has been transformed by this
494	/// transformer.
495	///
496	/// Local declarations are typically transformed via a call to
497	/// TransformDefinition. However, in some cases (e.g., lambda expressions),
498	/// the transformer itself has to transform the declarations. This routine
499	/// can be overridden by a subclass that keeps track of such mappings.
500	void transformedLocalDecl(Decl Old, ArrayRef<Decl > New) {
501	assert(New.size() == 1 &&(static_cast <bool> (New.size() == 1 && "must override transformedLocalDecl if performing pack expansion" ) ? void (0) : __assert_fail ("New.size() == 1 && \"must override transformedLocalDecl if performing pack expansion\"" , "clang/lib/Sema/TreeTransform.h", 502, __extension__ __PRETTY_FUNCTION__ ))
502	"must override transformedLocalDecl if performing pack expansion")(static_cast <bool> (New.size() == 1 && "must override transformedLocalDecl if performing pack expansion" ) ? void (0) : __assert_fail ("New.size() == 1 && \"must override transformedLocalDecl if performing pack expansion\"" , "clang/lib/Sema/TreeTransform.h", 502, __extension__ __PRETTY_FUNCTION__ ));
503	TransformedLocalDecls[Old] = New.front();
504	}
505
506	/// Transform the definition of the given declaration.
507	///
508	/// By default, invokes TransformDecl() to transform the declaration.
509	/// Subclasses may override this function to provide alternate behavior.
510	Decl TransformDefinition(SourceLocation Loc, Decl D) {
511	return getDerived().TransformDecl(Loc, D);
512	}
513
514	/// Transform the given declaration, which was the first part of a
515	/// nested-name-specifier in a member access expression.
516	///
517	/// This specific declaration transformation only applies to the first
518	/// identifier in a nested-name-specifier of a member access expression, e.g.,
519	/// the \c T in \c x->T::member
520	///
521	/// By default, invokes TransformDecl() to transform the declaration.
522	/// Subclasses may override this function to provide alternate behavior.
523	NamedDecl TransformFirstQualifierInScope(NamedDecl D, SourceLocation Loc) {
524	return cast_or_null<NamedDecl>(getDerived().TransformDecl(Loc, D));
525	}
526
527	/// Transform the set of declarations in an OverloadExpr.
528	bool TransformOverloadExprDecls(OverloadExpr *Old, bool RequiresADL,
529	LookupResult &R);
530
531	/// Transform the given nested-name-specifier with source-location
532	/// information.
533	///
534	/// By default, transforms all of the types and declarations within the
535	/// nested-name-specifier. Subclasses may override this function to provide
536	/// alternate behavior.
537	NestedNameSpecifierLoc
538	TransformNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,
539	QualType ObjectType = QualType(),
540	NamedDecl *FirstQualifierInScope = nullptr);
541
542	/// Transform the given declaration name.
543	///
544	/// By default, transforms the types of conversion function, constructor,
545	/// and destructor names and then (if needed) rebuilds the declaration name.
546	/// Identifiers and selectors are returned unmodified. Subclasses may
547	/// override this function to provide alternate behavior.
548	DeclarationNameInfo
549	TransformDeclarationNameInfo(const DeclarationNameInfo &NameInfo);
550
551	bool TransformRequiresExprRequirements(ArrayRef<concepts::Requirement *> Reqs,
552	llvm::SmallVectorImpl<concepts::Requirement *> &Transformed);
553	concepts::TypeRequirement *
554	TransformTypeRequirement(concepts::TypeRequirement *Req);
555	concepts::ExprRequirement *
556	TransformExprRequirement(concepts::ExprRequirement *Req);
557	concepts::NestedRequirement *
558	TransformNestedRequirement(concepts::NestedRequirement *Req);
559
560	/// Transform the given template name.
561	///
562	/// \param SS The nested-name-specifier that qualifies the template
563	/// name. This nested-name-specifier must already have been transformed.
564	///
565	/// \param Name The template name to transform.
566	///
567	/// \param NameLoc The source location of the template name.
568	///
569	/// \param ObjectType If we're translating a template name within a member
570	/// access expression, this is the type of the object whose member template
571	/// is being referenced.
572	///
573	/// \param FirstQualifierInScope If the first part of a nested-name-specifier
574	/// also refers to a name within the current (lexical) scope, this is the
575	/// declaration it refers to.
576	///
577	/// By default, transforms the template name by transforming the declarations
578	/// and nested-name-specifiers that occur within the template name.
579	/// Subclasses may override this function to provide alternate behavior.
580	TemplateName
581	TransformTemplateName(CXXScopeSpec &SS, TemplateName Name,
582	SourceLocation NameLoc,
583	QualType ObjectType = QualType(),
584	NamedDecl *FirstQualifierInScope = nullptr,
585	bool AllowInjectedClassName = false);
586
587	/// Transform the given template argument.
588	///
589	/// By default, this operation transforms the type, expression, or
590	/// declaration stored within the template argument and constructs a
591	/// new template argument from the transformed result. Subclasses may
592	/// override this function to provide alternate behavior.
593	///
594	/// Returns true if there was an error.
595	bool TransformTemplateArgument(const TemplateArgumentLoc &Input,
596	TemplateArgumentLoc &Output,
597	bool Uneval = false);
598
599	/// Transform the given set of template arguments.
600	///
601	/// By default, this operation transforms all of the template arguments
602	/// in the input set using \c TransformTemplateArgument(), and appends
603	/// the transformed arguments to the output list.
604	///
605	/// Note that this overload of \c TransformTemplateArguments() is merely
606	/// a convenience function. Subclasses that wish to override this behavior
607	/// should override the iterator-based member template version.
608	///
609	/// \param Inputs The set of template arguments to be transformed.
610	///
611	/// \param NumInputs The number of template arguments in \p Inputs.
612	///
613	/// \param Outputs The set of transformed template arguments output by this
614	/// routine.
615	///
616	/// Returns true if an error occurred.
617	bool TransformTemplateArguments(const TemplateArgumentLoc *Inputs,
618	unsigned NumInputs,
619	TemplateArgumentListInfo &Outputs,
620	bool Uneval = false) {
621	return TransformTemplateArguments(Inputs, Inputs + NumInputs, Outputs,
622	Uneval);
623	}
624
625	/// Transform the given set of template arguments.
626	///
627	/// By default, this operation transforms all of the template arguments
628	/// in the input set using \c TransformTemplateArgument(), and appends
629	/// the transformed arguments to the output list.
630	///
631	/// \param First An iterator to the first template argument.
632	///
633	/// \param Last An iterator one step past the last template argument.
634	///
635	/// \param Outputs The set of transformed template arguments output by this
636	/// routine.
637	///
638	/// Returns true if an error occurred.
639	template<typename InputIterator>
640	bool TransformTemplateArguments(InputIterator First,
641	InputIterator Last,
642	TemplateArgumentListInfo &Outputs,
643	bool Uneval = false);
644
645	/// Fakes up a TemplateArgumentLoc for a given TemplateArgument.
646	void InventTemplateArgumentLoc(const TemplateArgument &Arg,
647	TemplateArgumentLoc &ArgLoc);
648
649	/// Fakes up a TypeSourceInfo for a type.
650	TypeSourceInfo *InventTypeSourceInfo(QualType T) {
651	return SemaRef.Context.getTrivialTypeSourceInfo(T,
652	getDerived().getBaseLocation());
653	}
654
655	#define ABSTRACT_TYPELOC(CLASS, PARENT)
656	#define TYPELOC(CLASS, PARENT) \
657	QualType Transform##CLASS##Type(TypeLocBuilder &TLB, CLASS##TypeLoc T);
658	#include "clang/AST/TypeLocNodes.def"
659
660	QualType TransformTemplateTypeParmType(TypeLocBuilder &TLB,
661	TemplateTypeParmTypeLoc TL,
662	bool SuppressObjCLifetime);
663	QualType
664	TransformSubstTemplateTypeParmPackType(TypeLocBuilder &TLB,
665	SubstTemplateTypeParmPackTypeLoc TL,
666	bool SuppressObjCLifetime);
667
668	template<typename Fn>
669	QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
670	FunctionProtoTypeLoc TL,
671	CXXRecordDecl *ThisContext,
672	Qualifiers ThisTypeQuals,
673	Fn TransformExceptionSpec);
674
675	bool TransformExceptionSpec(SourceLocation Loc,
676	FunctionProtoType::ExceptionSpecInfo &ESI,
677	SmallVectorImpl<QualType> &Exceptions,
678	bool &Changed);
679
680	StmtResult TransformSEHHandler(Stmt *Handler);
681
682	QualType
683	TransformTemplateSpecializationType(TypeLocBuilder &TLB,
684	TemplateSpecializationTypeLoc TL,
685	TemplateName Template);
686
687	QualType
688	TransformDependentTemplateSpecializationType(TypeLocBuilder &TLB,
689	DependentTemplateSpecializationTypeLoc TL,
690	TemplateName Template,
691	CXXScopeSpec &SS);
692
693	QualType TransformDependentTemplateSpecializationType(
694	TypeLocBuilder &TLB, DependentTemplateSpecializationTypeLoc TL,
695	NestedNameSpecifierLoc QualifierLoc);
696
697	/// Transforms the parameters of a function type into the
698	/// given vectors.
699	///
700	/// The result vectors should be kept in sync; null entries in the
701	/// variables vector are acceptable.
702	///
703	/// LastParamTransformed, if non-null, will be set to the index of the last
704	/// parameter on which transfromation was started. In the event of an error,
705	/// this will contain the parameter which failed to instantiate.
706	///
707	/// Return true on error.
708	bool TransformFunctionTypeParams(
709	SourceLocation Loc, ArrayRef<ParmVarDecl *> Params,
710	const QualType *ParamTypes,
711	const FunctionProtoType::ExtParameterInfo *ParamInfos,
712	SmallVectorImpl<QualType> &PTypes, SmallVectorImpl<ParmVarDecl > PVars,
713	Sema::ExtParameterInfoBuilder &PInfos, unsigned *LastParamTransformed);
714
715	bool TransformFunctionTypeParams(
716	SourceLocation Loc, ArrayRef<ParmVarDecl *> Params,
717	const QualType *ParamTypes,
718	const FunctionProtoType::ExtParameterInfo *ParamInfos,
719	SmallVectorImpl<QualType> &PTypes, SmallVectorImpl<ParmVarDecl > PVars,
720	Sema::ExtParameterInfoBuilder &PInfos) {
721	return getDerived().TransformFunctionTypeParams(
722	Loc, Params, ParamTypes, ParamInfos, PTypes, PVars, PInfos, nullptr);
723	}
724
725	/// Transforms the parameters of a requires expresison into the given vectors.
726	///
727	/// The result vectors should be kept in sync; null entries in the
728	/// variables vector are acceptable.
729	///
730	/// Returns an unset ExprResult on success. Returns an ExprResult the 'not
731	/// satisfied' RequiresExpr if subsitution failed, OR an ExprError, both of
732	/// which are cases where transformation shouldn't continue.
733	ExprResult TransformRequiresTypeParams(
734	SourceLocation KWLoc, SourceLocation RBraceLoc, const RequiresExpr *RE,
735	RequiresExprBodyDecl Body, ArrayRef<ParmVarDecl > Params,
736	SmallVectorImpl<QualType> &PTypes,
737	SmallVectorImpl<ParmVarDecl *> &TransParams,
738	Sema::ExtParameterInfoBuilder &PInfos) {
739	if (getDerived().TransformFunctionTypeParams(
740	KWLoc, Params, /ParamTypes=/nullptr,
741	/ParamInfos=/nullptr, PTypes, &TransParams, PInfos))
742	return ExprError();
743
744	return ExprResult{};
745	}
746
747	/// Transforms a single function-type parameter. Return null
748	/// on error.
749	///
750	/// \param indexAdjustment - A number to add to the parameter's
751	/// scope index; can be negative
752	ParmVarDecl TransformFunctionTypeParam(ParmVarDecl OldParm,
753	int indexAdjustment,
754	std::optional<unsigned> NumExpansions,
755	bool ExpectParameterPack);
756
757	/// Transform the body of a lambda-expression.
758	StmtResult TransformLambdaBody(LambdaExpr E, Stmt Body);
759	/// Alternative implementation of TransformLambdaBody that skips transforming
760	/// the body.
761	StmtResult SkipLambdaBody(LambdaExpr E, Stmt Body);
762
763	QualType TransformReferenceType(TypeLocBuilder &TLB, ReferenceTypeLoc TL);
764
765	StmtResult TransformCompoundStmt(CompoundStmt *S, bool IsStmtExpr);
766	ExprResult TransformCXXNamedCastExpr(CXXNamedCastExpr *E);
767
768	TemplateParameterList *TransformTemplateParameterList(
769	TemplateParameterList *TPL) {
770	return TPL;
771	}
772
773	ExprResult TransformAddressOfOperand(Expr *E);
774
775	ExprResult TransformDependentScopeDeclRefExpr(DependentScopeDeclRefExpr *E,
776	bool IsAddressOfOperand,
777	TypeSourceInfo **RecoveryTSI);
778
779	ExprResult TransformParenDependentScopeDeclRefExpr(
780	ParenExpr PE, DependentScopeDeclRefExpr DRE, bool IsAddressOfOperand,
781	TypeSourceInfo **RecoveryTSI);
782
783	StmtResult TransformOMPExecutableDirective(OMPExecutableDirective *S);
784
785	// FIXME: We use LLVM_ATTRIBUTE_NOINLINE because inlining causes a ridiculous
786	// amount of stack usage with clang.
787	#define STMT(Node, Parent) \
788	LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) \
789	StmtResult Transform##Node(Node *S);
790	#define VALUESTMT(Node, Parent) \
791	LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) \
792	StmtResult Transform##Node(Node *S, StmtDiscardKind SDK);
793	#define EXPR(Node, Parent) \
794	LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) \
795	ExprResult Transform##Node(Node *E);
796	#define ABSTRACT_STMT(Stmt)
797	#include "clang/AST/StmtNodes.inc"
798
799	#define GEN_CLANG_CLAUSE_CLASS
800	#define CLAUSE_CLASS(Enum, Str, Class) \
801	LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) \
802	OMPClause Transform##Class(Class S);
803	#include "llvm/Frontend/OpenMP/OMP.inc"
804
805	/// Build a new qualified type given its unqualified type and type location.
806	///
807	/// By default, this routine adds type qualifiers only to types that can
808	/// have qualifiers, and silently suppresses those qualifiers that are not
809	/// permitted. Subclasses may override this routine to provide different
810	/// behavior.
811	QualType RebuildQualifiedType(QualType T, QualifiedTypeLoc TL);
812
813	/// Build a new pointer type given its pointee type.
814	///
815	/// By default, performs semantic analysis when building the pointer type.
816	/// Subclasses may override this routine to provide different behavior.
817	QualType RebuildPointerType(QualType PointeeType, SourceLocation Sigil);
818
819	/// Build a new block pointer type given its pointee type.
820	///
821	/// By default, performs semantic analysis when building the block pointer
822	/// type. Subclasses may override this routine to provide different behavior.
823	QualType RebuildBlockPointerType(QualType PointeeType, SourceLocation Sigil);
824
825	/// Build a new reference type given the type it references.
826	///
827	/// By default, performs semantic analysis when building the
828	/// reference type. Subclasses may override this routine to provide
829	/// different behavior.
830	///
831	/// \param LValue whether the type was written with an lvalue sigil
832	/// or an rvalue sigil.
833	QualType RebuildReferenceType(QualType ReferentType,
834	bool LValue,
835	SourceLocation Sigil);
836
837	/// Build a new member pointer type given the pointee type and the
838	/// class type it refers into.
839	///
840	/// By default, performs semantic analysis when building the member pointer
841	/// type. Subclasses may override this routine to provide different behavior.
842	QualType RebuildMemberPointerType(QualType PointeeType, QualType ClassType,
843	SourceLocation Sigil);
844
845	QualType RebuildObjCTypeParamType(const ObjCTypeParamDecl *Decl,
846	SourceLocation ProtocolLAngleLoc,
847	ArrayRef<ObjCProtocolDecl *> Protocols,
848	ArrayRef<SourceLocation> ProtocolLocs,
849	SourceLocation ProtocolRAngleLoc);
850
851	/// Build an Objective-C object type.
852	///
853	/// By default, performs semantic analysis when building the object type.
854	/// Subclasses may override this routine to provide different behavior.
855	QualType RebuildObjCObjectType(QualType BaseType,
856	SourceLocation Loc,
857	SourceLocation TypeArgsLAngleLoc,
858	ArrayRef<TypeSourceInfo *> TypeArgs,
859	SourceLocation TypeArgsRAngleLoc,
860	SourceLocation ProtocolLAngleLoc,
861	ArrayRef<ObjCProtocolDecl *> Protocols,
862	ArrayRef<SourceLocation> ProtocolLocs,
863	SourceLocation ProtocolRAngleLoc);
864
865	/// Build a new Objective-C object pointer type given the pointee type.
866	///
867	/// By default, directly builds the pointer type, with no additional semantic
868	/// analysis.
869	QualType RebuildObjCObjectPointerType(QualType PointeeType,
870	SourceLocation Star);
871
872	/// Build a new array type given the element type, size
873	/// modifier, size of the array (if known), size expression, and index type
874	/// qualifiers.
875	///
876	/// By default, performs semantic analysis when building the array type.
877	/// Subclasses may override this routine to provide different behavior.
878	/// Also by default, all of the other Rebuild*Array
879	QualType RebuildArrayType(QualType ElementType,
880	ArrayType::ArraySizeModifier SizeMod,
881	const llvm::APInt *Size,
882	Expr *SizeExpr,
883	unsigned IndexTypeQuals,
884	SourceRange BracketsRange);
885
886	/// Build a new constant array type given the element type, size
887	/// modifier, (known) size of the array, and index type qualifiers.
888	///
889	/// By default, performs semantic analysis when building the array type.
890	/// Subclasses may override this routine to provide different behavior.
891	QualType RebuildConstantArrayType(QualType ElementType,
892	ArrayType::ArraySizeModifier SizeMod,
893	const llvm::APInt &Size,
894	Expr *SizeExpr,
895	unsigned IndexTypeQuals,
896	SourceRange BracketsRange);
897
898	/// Build a new incomplete array type given the element type, size
899	/// modifier, and index type qualifiers.
900	///
901	/// By default, performs semantic analysis when building the array type.
902	/// Subclasses may override this routine to provide different behavior.
903	QualType RebuildIncompleteArrayType(QualType ElementType,
904	ArrayType::ArraySizeModifier SizeMod,
905	unsigned IndexTypeQuals,
906	SourceRange BracketsRange);
907
908	/// Build a new variable-length array type given the element type,
909	/// size modifier, size expression, and index type qualifiers.
910	///
911	/// By default, performs semantic analysis when building the array type.
912	/// Subclasses may override this routine to provide different behavior.
913	QualType RebuildVariableArrayType(QualType ElementType,
914	ArrayType::ArraySizeModifier SizeMod,
915	Expr *SizeExpr,
916	unsigned IndexTypeQuals,
917	SourceRange BracketsRange);
918
919	/// Build a new dependent-sized array type given the element type,
920	/// size modifier, size expression, and index type qualifiers.
921	///
922	/// By default, performs semantic analysis when building the array type.
923	/// Subclasses may override this routine to provide different behavior.
924	QualType RebuildDependentSizedArrayType(QualType ElementType,
925	ArrayType::ArraySizeModifier SizeMod,
926	Expr *SizeExpr,
927	unsigned IndexTypeQuals,
928	SourceRange BracketsRange);
929
930	/// Build a new vector type given the element type and
931	/// number of elements.
932	///
933	/// By default, performs semantic analysis when building the vector type.
934	/// Subclasses may override this routine to provide different behavior.
935	QualType RebuildVectorType(QualType ElementType, unsigned NumElements,
936	VectorType::VectorKind VecKind);
937
938	/// Build a new potentially dependently-sized extended vector type
939	/// given the element type and number of elements.
940	///
941	/// By default, performs semantic analysis when building the vector type.
942	/// Subclasses may override this routine to provide different behavior.
943	QualType RebuildDependentVectorType(QualType ElementType, Expr *SizeExpr,
944	SourceLocation AttributeLoc,
945	VectorType::VectorKind);
946
947	/// Build a new extended vector type given the element type and
948	/// number of elements.
949	///
950	/// By default, performs semantic analysis when building the vector type.
951	/// Subclasses may override this routine to provide different behavior.
952	QualType RebuildExtVectorType(QualType ElementType, unsigned NumElements,
953	SourceLocation AttributeLoc);
954
955	/// Build a new potentially dependently-sized extended vector type
956	/// given the element type and number of elements.
957	///
958	/// By default, performs semantic analysis when building the vector type.
959	/// Subclasses may override this routine to provide different behavior.
960	QualType RebuildDependentSizedExtVectorType(QualType ElementType,
961	Expr *SizeExpr,
962	SourceLocation AttributeLoc);
963
964	/// Build a new matrix type given the element type and dimensions.
965	QualType RebuildConstantMatrixType(QualType ElementType, unsigned NumRows,
966	unsigned NumColumns);
967
968	/// Build a new matrix type given the type and dependently-defined
969	/// dimensions.
970	QualType RebuildDependentSizedMatrixType(QualType ElementType, Expr *RowExpr,
971	Expr *ColumnExpr,
972	SourceLocation AttributeLoc);
973
974	/// Build a new DependentAddressSpaceType or return the pointee
975	/// type variable with the correct address space (retrieved from
976	/// AddrSpaceExpr) applied to it. The former will be returned in cases
977	/// where the address space remains dependent.
978	///
979	/// By default, performs semantic analysis when building the type with address
980	/// space applied. Subclasses may override this routine to provide different
981	/// behavior.
982	QualType RebuildDependentAddressSpaceType(QualType PointeeType,
983	Expr *AddrSpaceExpr,
984	SourceLocation AttributeLoc);
985
986	/// Build a new function type.
987	///
988	/// By default, performs semantic analysis when building the function type.
989	/// Subclasses may override this routine to provide different behavior.
990	QualType RebuildFunctionProtoType(QualType T,
991	MutableArrayRef<QualType> ParamTypes,
992	const FunctionProtoType::ExtProtoInfo &EPI);
993
994	/// Build a new unprototyped function type.
995	QualType RebuildFunctionNoProtoType(QualType ResultType);
996
997	/// Rebuild an unresolved typename type, given the decl that
998	/// the UnresolvedUsingTypenameDecl was transformed to.
999	QualType RebuildUnresolvedUsingType(SourceLocation NameLoc, Decl *D);
1000
1001	/// Build a new type found via an alias.
1002	QualType RebuildUsingType(UsingShadowDecl *Found, QualType Underlying) {
1003	return SemaRef.Context.getUsingType(Found, Underlying);
1004	}
1005
1006	/// Build a new typedef type.
1007	QualType RebuildTypedefType(TypedefNameDecl *Typedef) {
1008	return SemaRef.Context.getTypeDeclType(Typedef);
1009	}
1010
1011	/// Build a new MacroDefined type.
1012	QualType RebuildMacroQualifiedType(QualType T,
1013	const IdentifierInfo *MacroII) {
1014	return SemaRef.Context.getMacroQualifiedType(T, MacroII);
1015	}
1016
1017	/// Build a new class/struct/union type.
1018	QualType RebuildRecordType(RecordDecl *Record) {
1019	return SemaRef.Context.getTypeDeclType(Record);
1020	}
1021
1022	/// Build a new Enum type.
1023	QualType RebuildEnumType(EnumDecl *Enum) {
1024	return SemaRef.Context.getTypeDeclType(Enum);
1025	}
1026
1027	/// Build a new typeof(expr) type.
1028	///
1029	/// By default, performs semantic analysis when building the typeof type.
1030	/// Subclasses may override this routine to provide different behavior.
1031	QualType RebuildTypeOfExprType(Expr *Underlying, SourceLocation Loc,
1032	TypeOfKind Kind);
1033
1034	/// Build a new typeof(type) type.
1035	///
1036	/// By default, builds a new TypeOfType with the given underlying type.
1037	QualType RebuildTypeOfType(QualType Underlying, TypeOfKind Kind);
1038
1039	/// Build a new unary transform type.
1040	QualType RebuildUnaryTransformType(QualType BaseType,
1041	UnaryTransformType::UTTKind UKind,
1042	SourceLocation Loc);
1043
1044	/// Build a new C++11 decltype type.
1045	///
1046	/// By default, performs semantic analysis when building the decltype type.
1047	/// Subclasses may override this routine to provide different behavior.
1048	QualType RebuildDecltypeType(Expr *Underlying, SourceLocation Loc);
1049
1050	/// Build a new C++11 auto type.
1051	///
1052	/// By default, builds a new AutoType with the given deduced type.
1053	QualType RebuildAutoType(QualType Deduced, AutoTypeKeyword Keyword,
1054	ConceptDecl *TypeConstraintConcept,
1055	ArrayRef<TemplateArgument> TypeConstraintArgs) {
1056	// Note, IsDependent is always false here: we implicitly convert an 'auto'
1057	// which has been deduced to a dependent type into an undeduced 'auto', so
1058	// that we'll retry deduction after the transformation.
1059	return SemaRef.Context.getAutoType(Deduced, Keyword,
1060	/IsDependent/ false, /IsPack=/false,
1061	TypeConstraintConcept,
1062	TypeConstraintArgs);
1063	}
1064
1065	/// By default, builds a new DeducedTemplateSpecializationType with the given
1066	/// deduced type.
1067	QualType RebuildDeducedTemplateSpecializationType(TemplateName Template,
1068	QualType Deduced) {
1069	return SemaRef.Context.getDeducedTemplateSpecializationType(
1070	Template, Deduced, /IsDependent/ false);
1071	}
1072
1073	/// Build a new template specialization type.
1074	///
1075	/// By default, performs semantic analysis when building the template
1076	/// specialization type. Subclasses may override this routine to provide
1077	/// different behavior.
1078	QualType RebuildTemplateSpecializationType(TemplateName Template,
1079	SourceLocation TemplateLoc,
1080	TemplateArgumentListInfo &Args);
1081
1082	/// Build a new parenthesized type.
1083	///
1084	/// By default, builds a new ParenType type from the inner type.
1085	/// Subclasses may override this routine to provide different behavior.
1086	QualType RebuildParenType(QualType InnerType) {
1087	return SemaRef.BuildParenType(InnerType);
1088	}
1089
1090	/// Build a new qualified name type.
1091	///
1092	/// By default, builds a new ElaboratedType type from the keyword,
1093	/// the nested-name-specifier and the named type.
1094	/// Subclasses may override this routine to provide different behavior.
1095	QualType RebuildElaboratedType(SourceLocation KeywordLoc,
1096	ElaboratedTypeKeyword Keyword,
1097	NestedNameSpecifierLoc QualifierLoc,
1098	QualType Named) {
1099	return SemaRef.Context.getElaboratedType(Keyword,
1100	QualifierLoc.getNestedNameSpecifier(),
1101	Named);
1102	}
1103
1104	/// Build a new typename type that refers to a template-id.
1105	///
1106	/// By default, builds a new DependentNameType type from the
1107	/// nested-name-specifier and the given type. Subclasses may override
1108	/// this routine to provide different behavior.
1109	QualType RebuildDependentTemplateSpecializationType(
1110	ElaboratedTypeKeyword Keyword,
1111	NestedNameSpecifierLoc QualifierLoc,
1112	SourceLocation TemplateKWLoc,
1113	const IdentifierInfo *Name,
1114	SourceLocation NameLoc,
1115	TemplateArgumentListInfo &Args,
1116	bool AllowInjectedClassName) {
1117	// Rebuild the template name.
1118	// TODO: avoid TemplateName abstraction
1119	CXXScopeSpec SS;
1120	SS.Adopt(QualifierLoc);
1121	TemplateName InstName = getDerived().RebuildTemplateName(
1122	SS, TemplateKWLoc, *Name, NameLoc, QualType(), nullptr,
1123	AllowInjectedClassName);
1124
1125	if (InstName.isNull())
1126	return QualType();
1127
1128	// If it's still dependent, make a dependent specialization.
1129	if (InstName.getAsDependentTemplateName())
1130	return SemaRef.Context.getDependentTemplateSpecializationType(
1131	Keyword, QualifierLoc.getNestedNameSpecifier(), Name,
1132	Args.arguments());
1133
1134	// Otherwise, make an elaborated type wrapping a non-dependent
1135	// specialization.
1136	QualType T =
1137	getDerived().RebuildTemplateSpecializationType(InstName, NameLoc, Args);
1138	if (T.isNull())
1139	return QualType();
1140	return SemaRef.Context.getElaboratedType(
1141	Keyword, QualifierLoc.getNestedNameSpecifier(), T);
1142	}
1143
1144	/// Build a new typename type that refers to an identifier.
1145	///
1146	/// By default, performs semantic analysis when building the typename type
1147	/// (or elaborated type). Subclasses may override this routine to provide
1148	/// different behavior.
1149	QualType RebuildDependentNameType(ElaboratedTypeKeyword Keyword,
1150	SourceLocation KeywordLoc,
1151	NestedNameSpecifierLoc QualifierLoc,
1152	const IdentifierInfo *Id,
1153	SourceLocation IdLoc,
1154	bool DeducedTSTContext) {
1155	CXXScopeSpec SS;
1156	SS.Adopt(QualifierLoc);
1157
1158	if (QualifierLoc.getNestedNameSpecifier()->isDependent()) {
1159	// If the name is still dependent, just build a new dependent name type.
1160	if (!SemaRef.computeDeclContext(SS))
1161	return SemaRef.Context.getDependentNameType(Keyword,
1162	QualifierLoc.getNestedNameSpecifier(),
1163	Id);
1164	}
1165
1166	if (Keyword == ETK_None \|\| Keyword == ETK_Typename) {
1167	return SemaRef.CheckTypenameType(Keyword, KeywordLoc, QualifierLoc,
1168	*Id, IdLoc, DeducedTSTContext);
1169	}
1170
1171	TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForKeyword(Keyword);
1172
1173	// We had a dependent elaborated-type-specifier that has been transformed
1174	// into a non-dependent elaborated-type-specifier. Find the tag we're
1175	// referring to.
1176	LookupResult Result(SemaRef, Id, IdLoc, Sema::LookupTagName);
1177	DeclContext *DC = SemaRef.computeDeclContext(SS, false);
1178	if (!DC)
1179	return QualType();
1180
1181	if (SemaRef.RequireCompleteDeclContext(SS, DC))
1182	return QualType();
1183
1184	TagDecl *Tag = nullptr;
1185	SemaRef.LookupQualifiedName(Result, DC);
1186	switch (Result.getResultKind()) {
1187	case LookupResult::NotFound:
1188	case LookupResult::NotFoundInCurrentInstantiation:
1189	break;
1190
1191	case LookupResult::Found:
1192	Tag = Result.getAsSingle<TagDecl>();
1193	break;
1194
1195	case LookupResult::FoundOverloaded:
1196	case LookupResult::FoundUnresolvedValue:
1197	llvm_unreachable("Tag lookup cannot find non-tags")::llvm::llvm_unreachable_internal("Tag lookup cannot find non-tags" , "clang/lib/Sema/TreeTransform.h", 1197);
1198
1199	case LookupResult::Ambiguous:
1200	// Let the LookupResult structure handle ambiguities.
1201	return QualType();
1202	}
1203
1204	if (!Tag) {
1205	// Check where the name exists but isn't a tag type and use that to emit
1206	// better diagnostics.
1207	LookupResult Result(SemaRef, Id, IdLoc, Sema::LookupTagName);
1208	SemaRef.LookupQualifiedName(Result, DC);
1209	switch (Result.getResultKind()) {
1210	case LookupResult::Found:
1211	case LookupResult::FoundOverloaded:
1212	case LookupResult::FoundUnresolvedValue: {
1213	NamedDecl *SomeDecl = Result.getRepresentativeDecl();
1214	Sema::NonTagKind NTK = SemaRef.getNonTagTypeDeclKind(SomeDecl, Kind);
1215	SemaRef.Diag(IdLoc, diag::err_tag_reference_non_tag) << SomeDecl
1216	<< NTK << Kind;
1217	SemaRef.Diag(SomeDecl->getLocation(), diag::note_declared_at);
1218	break;
1219	}
1220	default:
1221	SemaRef.Diag(IdLoc, diag::err_not_tag_in_scope)
1222	<< Kind << Id << DC << QualifierLoc.getSourceRange();
1223	break;
1224	}
1225	return QualType();
1226	}
1227
1228	if (!SemaRef.isAcceptableTagRedeclaration(Tag, Kind, /isDefinition/false,
1229	IdLoc, Id)) {
1230	SemaRef.Diag(KeywordLoc, diag::err_use_with_wrong_tag) << Id;
1231	SemaRef.Diag(Tag->getLocation(), diag::note_previous_use);
1232	return QualType();
1233	}
1234
1235	// Build the elaborated-type-specifier type.
1236	QualType T = SemaRef.Context.getTypeDeclType(Tag);
1237	return SemaRef.Context.getElaboratedType(Keyword,
1238	QualifierLoc.getNestedNameSpecifier(),
1239	T);
1240	}
1241
1242	/// Build a new pack expansion type.
1243	///
1244	/// By default, builds a new PackExpansionType type from the given pattern.
1245	/// Subclasses may override this routine to provide different behavior.
1246	QualType RebuildPackExpansionType(QualType Pattern, SourceRange PatternRange,
1247	SourceLocation EllipsisLoc,
1248	std::optional<unsigned> NumExpansions) {
1249	return getSema().CheckPackExpansion(Pattern, PatternRange, EllipsisLoc,
1250	NumExpansions);
1251	}
1252
1253	/// Build a new atomic type given its value type.
1254	///
1255	/// By default, performs semantic analysis when building the atomic type.
1256	/// Subclasses may override this routine to provide different behavior.
1257	QualType RebuildAtomicType(QualType ValueType, SourceLocation KWLoc);
1258
1259	/// Build a new pipe type given its value type.
1260	QualType RebuildPipeType(QualType ValueType, SourceLocation KWLoc,
1261	bool isReadPipe);
1262
1263	/// Build a bit-precise int given its value type.
1264	QualType RebuildBitIntType(bool IsUnsigned, unsigned NumBits,
1265	SourceLocation Loc);
1266
1267	/// Build a dependent bit-precise int given its value type.
1268	QualType RebuildDependentBitIntType(bool IsUnsigned, Expr *NumBitsExpr,
1269	SourceLocation Loc);
1270
1271	/// Build a new template name given a nested name specifier, a flag
1272	/// indicating whether the "template" keyword was provided, and the template
1273	/// that the template name refers to.
1274	///
1275	/// By default, builds the new template name directly. Subclasses may override
1276	/// this routine to provide different behavior.
1277	TemplateName RebuildTemplateName(CXXScopeSpec &SS,
1278	bool TemplateKW,
1279	TemplateDecl *Template);
1280
1281	/// Build a new template name given a nested name specifier and the
1282	/// name that is referred to as a template.
1283	///
1284	/// By default, performs semantic analysis to determine whether the name can
1285	/// be resolved to a specific template, then builds the appropriate kind of
1286	/// template name. Subclasses may override this routine to provide different
1287	/// behavior.
1288	TemplateName RebuildTemplateName(CXXScopeSpec &SS,
1289	SourceLocation TemplateKWLoc,
1290	const IdentifierInfo &Name,
1291	SourceLocation NameLoc, QualType ObjectType,
1292	NamedDecl *FirstQualifierInScope,
1293	bool AllowInjectedClassName);
1294
1295	/// Build a new template name given a nested name specifier and the
1296	/// overloaded operator name that is referred to as a template.
1297	///
1298	/// By default, performs semantic analysis to determine whether the name can
1299	/// be resolved to a specific template, then builds the appropriate kind of
1300	/// template name. Subclasses may override this routine to provide different
1301	/// behavior.
1302	TemplateName RebuildTemplateName(CXXScopeSpec &SS,
1303	SourceLocation TemplateKWLoc,
1304	OverloadedOperatorKind Operator,
1305	SourceLocation NameLoc, QualType ObjectType,
1306	bool AllowInjectedClassName);
1307
1308	/// Build a new template name given a template template parameter pack
1309	/// and the
1310	///
1311	/// By default, performs semantic analysis to determine whether the name can
1312	/// be resolved to a specific template, then builds the appropriate kind of
1313	/// template name. Subclasses may override this routine to provide different
1314	/// behavior.
1315	TemplateName RebuildTemplateName(const TemplateArgument &ArgPack,
1316	Decl *AssociatedDecl, unsigned Index,
1317	bool Final) {
1318	return getSema().Context.getSubstTemplateTemplateParmPack(
1319	ArgPack, AssociatedDecl, Index, Final);
1320	}
1321
1322	/// Build a new compound statement.
1323	///
1324	/// By default, performs semantic analysis to build the new statement.
1325	/// Subclasses may override this routine to provide different behavior.
1326	StmtResult RebuildCompoundStmt(SourceLocation LBraceLoc,
1327	MultiStmtArg Statements,
1328	SourceLocation RBraceLoc,
1329	bool IsStmtExpr) {
1330	return getSema().ActOnCompoundStmt(LBraceLoc, RBraceLoc, Statements,
1331	IsStmtExpr);
1332	}
1333
1334	/// Build a new case statement.
1335	///
1336	/// By default, performs semantic analysis to build the new statement.
1337	/// Subclasses may override this routine to provide different behavior.
1338	StmtResult RebuildCaseStmt(SourceLocation CaseLoc,
1339	Expr *LHS,
1340	SourceLocation EllipsisLoc,
1341	Expr *RHS,
1342	SourceLocation ColonLoc) {
1343	return getSema().ActOnCaseStmt(CaseLoc, LHS, EllipsisLoc, RHS,
1344	ColonLoc);
1345	}
1346
1347	/// Attach the body to a new case statement.
1348	///
1349	/// By default, performs semantic analysis to build the new statement.
1350	/// Subclasses may override this routine to provide different behavior.
1351	StmtResult RebuildCaseStmtBody(Stmt S, Stmt Body) {
1352	getSema().ActOnCaseStmtBody(S, Body);
1353	return S;
1354	}
1355
1356	/// Build a new default statement.
1357	///
1358	/// By default, performs semantic analysis to build the new statement.
1359	/// Subclasses may override this routine to provide different behavior.
1360	StmtResult RebuildDefaultStmt(SourceLocation DefaultLoc,
1361	SourceLocation ColonLoc,
1362	Stmt *SubStmt) {
1363	return getSema().ActOnDefaultStmt(DefaultLoc, ColonLoc, SubStmt,
1364	/CurScope=/nullptr);
1365	}
1366
1367	/// Build a new label statement.
1368	///
1369	/// By default, performs semantic analysis to build the new statement.
1370	/// Subclasses may override this routine to provide different behavior.
1371	StmtResult RebuildLabelStmt(SourceLocation IdentLoc, LabelDecl *L,
1372	SourceLocation ColonLoc, Stmt *SubStmt) {
1373	return SemaRef.ActOnLabelStmt(IdentLoc, L, ColonLoc, SubStmt);
1374	}
1375
1376	/// Build a new attributed statement.
1377	///
1378	/// By default, performs semantic analysis to build the new statement.
1379	/// Subclasses may override this routine to provide different behavior.
1380	StmtResult RebuildAttributedStmt(SourceLocation AttrLoc,
1381	ArrayRef<const Attr *> Attrs,
1382	Stmt *SubStmt) {
1383	return SemaRef.BuildAttributedStmt(AttrLoc, Attrs, SubStmt);
1384	}
1385
1386	/// Build a new "if" statement.
1387	///
1388	/// By default, performs semantic analysis to build the new statement.
1389	/// Subclasses may override this routine to provide different behavior.
1390	StmtResult RebuildIfStmt(SourceLocation IfLoc, IfStatementKind Kind,
1391	SourceLocation LParenLoc, Sema::ConditionResult Cond,
1392	SourceLocation RParenLoc, Stmt Init, Stmt Then,
1393	SourceLocation ElseLoc, Stmt *Else) {
1394	return getSema().ActOnIfStmt(IfLoc, Kind, LParenLoc, Init, Cond, RParenLoc,
1395	Then, ElseLoc, Else);
1396	}
1397
1398	/// Start building a new switch statement.
1399	///
1400	/// By default, performs semantic analysis to build the new statement.
1401	/// Subclasses may override this routine to provide different behavior.
1402	StmtResult RebuildSwitchStmtStart(SourceLocation SwitchLoc,
1403	SourceLocation LParenLoc, Stmt *Init,
1404	Sema::ConditionResult Cond,
1405	SourceLocation RParenLoc) {
1406	return getSema().ActOnStartOfSwitchStmt(SwitchLoc, LParenLoc, Init, Cond,
1407	RParenLoc);
1408	}
1409
1410	/// Attach the body to the switch statement.
1411	///
1412	/// By default, performs semantic analysis to build the new statement.
1413	/// Subclasses may override this routine to provide different behavior.
1414	StmtResult RebuildSwitchStmtBody(SourceLocation SwitchLoc,
1415	Stmt Switch, Stmt Body) {
1416	return getSema().ActOnFinishSwitchStmt(SwitchLoc, Switch, Body);
1417	}
1418
1419	/// Build a new while statement.
1420	///
1421	/// By default, performs semantic analysis to build the new statement.
1422	/// Subclasses may override this routine to provide different behavior.
1423	StmtResult RebuildWhileStmt(SourceLocation WhileLoc, SourceLocation LParenLoc,
1424	Sema::ConditionResult Cond,
1425	SourceLocation RParenLoc, Stmt *Body) {
1426	return getSema().ActOnWhileStmt(WhileLoc, LParenLoc, Cond, RParenLoc, Body);
1427	}
1428
1429	/// Build a new do-while statement.
1430	///
1431	/// By default, performs semantic analysis to build the new statement.
1432	/// Subclasses may override this routine to provide different behavior.
1433	StmtResult RebuildDoStmt(SourceLocation DoLoc, Stmt *Body,
1434	SourceLocation WhileLoc, SourceLocation LParenLoc,
1435	Expr *Cond, SourceLocation RParenLoc) {
1436	return getSema().ActOnDoStmt(DoLoc, Body, WhileLoc, LParenLoc,
1437	Cond, RParenLoc);
1438	}
1439
1440	/// Build a new for statement.
1441	///
1442	/// By default, performs semantic analysis to build the new statement.
1443	/// Subclasses may override this routine to provide different behavior.
1444	StmtResult RebuildForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
1445	Stmt *Init, Sema::ConditionResult Cond,
1446	Sema::FullExprArg Inc, SourceLocation RParenLoc,
1447	Stmt *Body) {
1448	return getSema().ActOnForStmt(ForLoc, LParenLoc, Init, Cond,
1449	Inc, RParenLoc, Body);
1450	}
1451
1452	/// Build a new goto statement.
1453	///
1454	/// By default, performs semantic analysis to build the new statement.
1455	/// Subclasses may override this routine to provide different behavior.
1456	StmtResult RebuildGotoStmt(SourceLocation GotoLoc, SourceLocation LabelLoc,
1457	LabelDecl *Label) {
1458	return getSema().ActOnGotoStmt(GotoLoc, LabelLoc, Label);
1459	}
1460
1461	/// Build a new indirect goto statement.
1462	///
1463	/// By default, performs semantic analysis to build the new statement.
1464	/// Subclasses may override this routine to provide different behavior.
1465	StmtResult RebuildIndirectGotoStmt(SourceLocation GotoLoc,
1466	SourceLocation StarLoc,
1467	Expr *Target) {
1468	return getSema().ActOnIndirectGotoStmt(GotoLoc, StarLoc, Target);
1469	}
1470
1471	/// Build a new return statement.
1472	///
1473	/// By default, performs semantic analysis to build the new statement.
1474	/// Subclasses may override this routine to provide different behavior.
1475	StmtResult RebuildReturnStmt(SourceLocation ReturnLoc, Expr *Result) {
1476	return getSema().BuildReturnStmt(ReturnLoc, Result);
1477	}
1478
1479	/// Build a new declaration statement.
1480	///
1481	/// By default, performs semantic analysis to build the new statement.
1482	/// Subclasses may override this routine to provide different behavior.
1483	StmtResult RebuildDeclStmt(MutableArrayRef<Decl *> Decls,
1484	SourceLocation StartLoc, SourceLocation EndLoc) {
1485	Sema::DeclGroupPtrTy DG = getSema().BuildDeclaratorGroup(Decls);
1486	return getSema().ActOnDeclStmt(DG, StartLoc, EndLoc);
1487	}
1488
1489	/// Build a new inline asm statement.
1490	///
1491	/// By default, performs semantic analysis to build the new statement.
1492	/// Subclasses may override this routine to provide different behavior.
1493	StmtResult RebuildGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
1494	bool IsVolatile, unsigned NumOutputs,
1495	unsigned NumInputs, IdentifierInfo **Names,
1496	MultiExprArg Constraints, MultiExprArg Exprs,
1497	Expr *AsmString, MultiExprArg Clobbers,
1498	unsigned NumLabels,
1499	SourceLocation RParenLoc) {
1500	return getSema().ActOnGCCAsmStmt(AsmLoc, IsSimple, IsVolatile, NumOutputs,
1501	NumInputs, Names, Constraints, Exprs,
1502	AsmString, Clobbers, NumLabels, RParenLoc);
1503	}
1504
1505	/// Build a new MS style inline asm statement.
1506	///
1507	/// By default, performs semantic analysis to build the new statement.
1508	/// Subclasses may override this routine to provide different behavior.
1509	StmtResult RebuildMSAsmStmt(SourceLocation AsmLoc, SourceLocation LBraceLoc,
1510	ArrayRef<Token> AsmToks,
1511	StringRef AsmString,
1512	unsigned NumOutputs, unsigned NumInputs,
1513	ArrayRef<StringRef> Constraints,
1514	ArrayRef<StringRef> Clobbers,
1515	ArrayRef<Expr*> Exprs,
1516	SourceLocation EndLoc) {
1517	return getSema().ActOnMSAsmStmt(AsmLoc, LBraceLoc, AsmToks, AsmString,
1518	NumOutputs, NumInputs,
1519	Constraints, Clobbers, Exprs, EndLoc);
1520	}
1521
1522	/// Build a new co_return statement.
1523	///
1524	/// By default, performs semantic analysis to build the new statement.
1525	/// Subclasses may override this routine to provide different behavior.
1526	StmtResult RebuildCoreturnStmt(SourceLocation CoreturnLoc, Expr *Result,
1527	bool IsImplicit) {
1528	return getSema().BuildCoreturnStmt(CoreturnLoc, Result, IsImplicit);
1529	}
1530
1531	/// Build a new co_await expression.
1532	///
1533	/// By default, performs semantic analysis to build the new expression.
1534	/// Subclasses may override this routine to provide different behavior.
1535	ExprResult RebuildCoawaitExpr(SourceLocation CoawaitLoc, Expr *Operand,
1536	UnresolvedLookupExpr *OpCoawaitLookup,
1537	bool IsImplicit) {
1538	// This function rebuilds a coawait-expr given its operator.
1539	// For an explicit coawait-expr, the rebuild involves the full set
1540	// of transformations performed by BuildUnresolvedCoawaitExpr(),
1541	// including calling await_transform().
1542	// For an implicit coawait-expr, we need to rebuild the "operator
1543	// coawait" but not await_transform(), so use BuildResolvedCoawaitExpr().
1544	// This mirrors how the implicit CoawaitExpr is originally created
1545	// in Sema::ActOnCoroutineBodyStart().
1546	if (IsImplicit) {
1547	ExprResult Suspend = getSema().BuildOperatorCoawaitCall(
1548	CoawaitLoc, Operand, OpCoawaitLookup);
1549	if (Suspend.isInvalid())
1550	return ExprError();
1551	return getSema().BuildResolvedCoawaitExpr(CoawaitLoc, Operand,
1552	Suspend.get(), true);
1553	}
1554
1555	return getSema().BuildUnresolvedCoawaitExpr(CoawaitLoc, Operand,
1556