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

Bug Summary

File:	build/source/clang/lib/Sema/SemaLambda.cpp
Warning:	line 1241, column 10 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 SemaLambda.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-16/lib/clang/16 -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 _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -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-16/lib/clang/16/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 1673003482 -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-2023-01-06-130334-16210-1 -x c++ /build/source/clang/lib/Sema/SemaLambda.cpp
1//===--- SemaLambda.cpp - Semantic Analysis for C++11 Lambdas -------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9//  This file implements semantic analysis for C++ lambda expressions.
10//
11//===----------------------------------------------------------------------===//
12#include "clang/Sema/DeclSpec.h"
13#include "TypeLocBuilder.h"
14#include "clang/AST/ASTLambda.h"
15#include "clang/AST/ExprCXX.h"
16#include "clang/Basic/TargetInfo.h"
17#include "clang/Sema/Initialization.h"
18#include "clang/Sema/Lookup.h"
19#include "clang/Sema/Scope.h"
20#include "clang/Sema/ScopeInfo.h"
21#include "clang/Sema/SemaInternal.h"
22#include "clang/Sema/SemaLambda.h"
23#include "llvm/ADT/STLExtras.h"
24using namespace clang;
25using namespace sema;

27/// Examines the FunctionScopeInfo stack to determine the nearest
28/// enclosing lambda (to the current lambda) that is 'capture-ready' for
29/// the variable referenced in the current lambda (i.e. \p VarToCapture).
30/// If successful, returns the index into Sema's FunctionScopeInfo stack
31/// of the capture-ready lambda's LambdaScopeInfo.
32///
33/// Climbs down the stack of lambdas (deepest nested lambda - i.e. current
34/// lambda - is on top) to determine the index of the nearest enclosing/outer
35/// lambda that is ready to capture the \p VarToCapture being referenced in
36/// the current lambda.
37/// As we climb down the stack, we want the index of the first such lambda -
38/// that is the lambda with the highest index that is 'capture-ready'.
39///
40/// A lambda 'L' is capture-ready for 'V' (var or this) if:
41///  - its enclosing context is non-dependent
42///  - and if the chain of lambdas between L and the lambda in which
43///    V is potentially used (i.e. the lambda at the top of the scope info
44///    stack), can all capture or have already captured V.
45/// If \p VarToCapture is 'null' then we are trying to capture 'this'.
46///
47/// Note that a lambda that is deemed 'capture-ready' still needs to be checked
48/// for whether it is 'capture-capable' (see
49/// getStackIndexOfNearestEnclosingCaptureCapableLambda), before it can truly
50/// capture.
51///
52/// \param FunctionScopes - Sema's stack of nested FunctionScopeInfo's (which a
53///  LambdaScopeInfo inherits from).  The current/deepest/innermost lambda
54///  is at the top of the stack and has the highest index.
55/// \param VarToCapture - the variable to capture.  If NULL, capture 'this'.
56///
57/// \returns An Optional<unsigned> Index that if evaluates to 'true' contains
58/// the index (into Sema's FunctionScopeInfo stack) of the innermost lambda
59/// which is capture-ready.  If the return value evaluates to 'false' then
60/// no lambda is capture-ready for \p VarToCapture.

62static inline Optional<unsigned>
63getStackIndexOfNearestEnclosingCaptureReadyLambda(
  ArrayRef<const clang::sema::FunctionScopeInfo *> FunctionScopes,
  VarDecl *VarToCapture) {
// Label failure to capture.
const Optional<unsigned> NoLambdaIsCaptureReady;

// Ignore all inner captured regions.
unsigned CurScopeIndex = FunctionScopes.size() - 1;
while (CurScopeIndex > 0 && isa<clang::sema::CapturedRegionScopeInfo>(
                                FunctionScopes[CurScopeIndex]))
  --CurScopeIndex;
assert((static_cast <bool> (isa<clang::sema::LambdaScopeInfo
>(FunctionScopes[CurScopeIndex]) && "The function on the top of sema's function-info stack must be a lambda"
) ? void (0) : __assert_fail ("isa<clang::sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]) && \"The function on the top of sema's function-info stack must be a lambda\""
, "clang/lib/Sema/SemaLambda.cpp", 76, __extension__ __PRETTY_FUNCTION__
))
    isa<clang::sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]) &&(static_cast <bool> (isa<clang::sema::LambdaScopeInfo
>(FunctionScopes[CurScopeIndex]) && "The function on the top of sema's function-info stack must be a lambda"
) ? void (0) : __assert_fail ("isa<clang::sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]) && \"The function on the top of sema's function-info stack must be a lambda\""
, "clang/lib/Sema/SemaLambda.cpp", 76, __extension__ __PRETTY_FUNCTION__
))
    "The function on the top of sema's function-info stack must be a lambda")(static_cast <bool> (isa<clang::sema::LambdaScopeInfo
>(FunctionScopes[CurScopeIndex]) && "The function on the top of sema's function-info stack must be a lambda"
) ? void (0) : __assert_fail ("isa<clang::sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]) && \"The function on the top of sema's function-info stack must be a lambda\""
, "clang/lib/Sema/SemaLambda.cpp", 76, __extension__ __PRETTY_FUNCTION__
));

// If VarToCapture is null, we are attempting to capture 'this'.
const bool IsCapturingThis = !VarToCapture;
const bool IsCapturingVariable = !IsCapturingThis;

// Start with the current lambda at the top of the stack (highest index).
DeclContext *EnclosingDC =
    cast<sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex])->CallOperator;

do {
  const clang::sema::LambdaScopeInfo *LSI =
      cast<sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]);
  // IF we have climbed down to an intervening enclosing lambda that contains
  // the variable declaration - it obviously can/must not capture the
  // variable.
  // Since its enclosing DC is dependent, all the lambdas between it and the
  // innermost nested lambda are dependent (otherwise we wouldn't have
  // arrived here) - so we don't yet have a lambda that can capture the
  // variable.
  if (IsCapturingVariable &&
      VarToCapture->getDeclContext()->Equals(EnclosingDC))
    return NoLambdaIsCaptureReady;

  // For an enclosing lambda to be capture ready for an entity, all
  // intervening lambda's have to be able to capture that entity. If even
  // one of the intervening lambda's is not capable of capturing the entity
  // then no enclosing lambda can ever capture that entity.
  // For e.g.
  // const int x = 10;
  // [=](auto a) {    #1
  //   [](auto b) {   #2 <-- an intervening lambda that can never capture 'x'
  //    [=](auto c) { #3
  //       f(x, c);  <-- can not lead to x's speculative capture by #1 or #2
  //    }; }; };
  // If they do not have a default implicit capture, check to see
  // if the entity has already been explicitly captured.
  // If even a single dependent enclosing lambda lacks the capability
  // to ever capture this variable, there is no further enclosing
  // non-dependent lambda that can capture this variable.
  if (LSI->ImpCaptureStyle == sema::LambdaScopeInfo::ImpCap_None) {
    if (IsCapturingVariable && !LSI->isCaptured(VarToCapture))
      return NoLambdaIsCaptureReady;
    if (IsCapturingThis && !LSI->isCXXThisCaptured())
      return NoLambdaIsCaptureReady;
  }
  EnclosingDC = getLambdaAwareParentOfDeclContext(EnclosingDC);

  assert(CurScopeIndex)(static_cast <bool> (CurScopeIndex) ? void (0) : __assert_fail
 ("CurScopeIndex", "clang/lib/Sema/SemaLambda.cpp", 124, __extension__
 __PRETTY_FUNCTION__));
  --CurScopeIndex;
} while (!EnclosingDC->isTranslationUnit() &&
         EnclosingDC->isDependentContext() &&
         isLambdaCallOperator(EnclosingDC));

assert(CurScopeIndex < (FunctionScopes.size() - 1))(static_cast <bool> (CurScopeIndex < (FunctionScopes
.size() - 1)) ? void (0) : __assert_fail ("CurScopeIndex < (FunctionScopes.size() - 1)"
, "clang/lib/Sema/SemaLambda.cpp", 130, __extension__ __PRETTY_FUNCTION__
));
// If the enclosingDC is not dependent, then the immediately nested lambda
// (one index above) is capture-ready.
if (!EnclosingDC->isDependentContext())
  return CurScopeIndex + 1;
return NoLambdaIsCaptureReady;
136}

138/// Examines the FunctionScopeInfo stack to determine the nearest
139/// enclosing lambda (to the current lambda) that is 'capture-capable' for
140/// the variable referenced in the current lambda (i.e. \p VarToCapture).
141/// If successful, returns the index into Sema's FunctionScopeInfo stack
142/// of the capture-capable lambda's LambdaScopeInfo.
143///
144/// Given the current stack of lambdas being processed by Sema and
145/// the variable of interest, to identify the nearest enclosing lambda (to the
146/// current lambda at the top of the stack) that can truly capture
147/// a variable, it has to have the following two properties:
148///  a) 'capture-ready' - be the innermost lambda that is 'capture-ready':
149///     - climb down the stack (i.e. starting from the innermost and examining
150///       each outer lambda step by step) checking if each enclosing
151///       lambda can either implicitly or explicitly capture the variable.
152///       Record the first such lambda that is enclosed in a non-dependent
153///       context. If no such lambda currently exists return failure.
154///  b) 'capture-capable' - make sure the 'capture-ready' lambda can truly
155///  capture the variable by checking all its enclosing lambdas:
156///     - check if all outer lambdas enclosing the 'capture-ready' lambda
157///       identified above in 'a' can also capture the variable (this is done
158///       via tryCaptureVariable for variables and CheckCXXThisCapture for
159///       'this' by passing in the index of the Lambda identified in step 'a')
160///
161/// \param FunctionScopes - Sema's stack of nested FunctionScopeInfo's (which a
162/// LambdaScopeInfo inherits from).  The current/deepest/innermost lambda
163/// is at the top of the stack.
164///
165/// \param VarToCapture - the variable to capture.  If NULL, capture 'this'.
166///
167///
168/// \returns An Optional<unsigned> Index that if evaluates to 'true' contains
169/// the index (into Sema's FunctionScopeInfo stack) of the innermost lambda
170/// which is capture-capable.  If the return value evaluates to 'false' then
171/// no lambda is capture-capable for \p VarToCapture.

173Optional<unsigned> clang::getStackIndexOfNearestEnclosingCaptureCapableLambda(
  ArrayRef<const sema::FunctionScopeInfo *> FunctionScopes,
  VarDecl *VarToCapture, Sema &S) {

const Optional<unsigned> NoLambdaIsCaptureCapable;

const Optional<unsigned> OptionalStackIndex =
    getStackIndexOfNearestEnclosingCaptureReadyLambda(FunctionScopes,
                                                      VarToCapture);
if (!OptionalStackIndex)
  return NoLambdaIsCaptureCapable;

const unsigned IndexOfCaptureReadyLambda = *OptionalStackIndex;
assert(((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) ||(static_cast <bool> (((IndexOfCaptureReadyLambda != (FunctionScopes
.size() - 1)) || S.getCurGenericLambda()) && "The capture ready lambda for a potential capture can only be the "
 "current lambda if it is a generic lambda") ? void (0) : __assert_fail
 ("((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) || S.getCurGenericLambda()) && \"The capture ready lambda for a potential capture can only be the \" \"current lambda if it is a generic lambda\""
, "clang/lib/Sema/SemaLambda.cpp", 189, __extension__ __PRETTY_FUNCTION__
))
        S.getCurGenericLambda()) &&(static_cast <bool> (((IndexOfCaptureReadyLambda != (FunctionScopes
.size() - 1)) || S.getCurGenericLambda()) && "The capture ready lambda for a potential capture can only be the "
 "current lambda if it is a generic lambda") ? void (0) : __assert_fail
 ("((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) || S.getCurGenericLambda()) && \"The capture ready lambda for a potential capture can only be the \" \"current lambda if it is a generic lambda\""
, "clang/lib/Sema/SemaLambda.cpp", 189, __extension__ __PRETTY_FUNCTION__
))
       "The capture ready lambda for a potential capture can only be the "(static_cast <bool> (((IndexOfCaptureReadyLambda != (FunctionScopes
.size() - 1)) || S.getCurGenericLambda()) && "The capture ready lambda for a potential capture can only be the "
 "current lambda if it is a generic lambda") ? void (0) : __assert_fail
 ("((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) || S.getCurGenericLambda()) && \"The capture ready lambda for a potential capture can only be the \" \"current lambda if it is a generic lambda\""
, "clang/lib/Sema/SemaLambda.cpp", 189, __extension__ __PRETTY_FUNCTION__
))
       "current lambda if it is a generic lambda")(static_cast <bool> (((IndexOfCaptureReadyLambda != (FunctionScopes
.size() - 1)) || S.getCurGenericLambda()) && "The capture ready lambda for a potential capture can only be the "
 "current lambda if it is a generic lambda") ? void (0) : __assert_fail
 ("((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) || S.getCurGenericLambda()) && \"The capture ready lambda for a potential capture can only be the \" \"current lambda if it is a generic lambda\""
, "clang/lib/Sema/SemaLambda.cpp", 189, __extension__ __PRETTY_FUNCTION__
));

const sema::LambdaScopeInfo *const CaptureReadyLambdaLSI =
    cast<sema::LambdaScopeInfo>(FunctionScopes[IndexOfCaptureReadyLambda]);

// If VarToCapture is null, we are attempting to capture 'this'
const bool IsCapturingThis = !VarToCapture;
const bool IsCapturingVariable = !IsCapturingThis;

if (IsCapturingVariable) {
  // Check if the capture-ready lambda can truly capture the variable, by
  // checking whether all enclosing lambdas of the capture-ready lambda allow
  // the capture - i.e. make sure it is capture-capable.
  QualType CaptureType, DeclRefType;
  const bool CanCaptureVariable =
      !S.tryCaptureVariable(VarToCapture,
                            /*ExprVarIsUsedInLoc*/ SourceLocation(),
                            clang::Sema::TryCapture_Implicit,
                            /*EllipsisLoc*/ SourceLocation(),
                            /*BuildAndDiagnose*/ false, CaptureType,
                            DeclRefType, &IndexOfCaptureReadyLambda);
  if (!CanCaptureVariable)
    return NoLambdaIsCaptureCapable;
} else {
  // Check if the capture-ready lambda can truly capture 'this' by checking
  // whether all enclosing lambdas of the capture-ready lambda can capture
  // 'this'.
  const bool CanCaptureThis =
      !S.CheckCXXThisCapture(
           CaptureReadyLambdaLSI->PotentialThisCaptureLocation,
           /*Explicit*/ false, /*BuildAndDiagnose*/ false,
           &IndexOfCaptureReadyLambda);
  if (!CanCaptureThis)
    return NoLambdaIsCaptureCapable;
}
return IndexOfCaptureReadyLambda;
225}

227static inline TemplateParameterList *
228getGenericLambdaTemplateParameterList(LambdaScopeInfo *LSI, Sema &SemaRef) {
if (!LSI->GLTemplateParameterList && !LSI->TemplateParams.empty()) {
  LSI->GLTemplateParameterList = TemplateParameterList::Create(
      SemaRef.Context,
      /*Template kw loc*/ SourceLocation(),
      /*L angle loc*/ LSI->ExplicitTemplateParamsRange.getBegin(),
      LSI->TemplateParams,
      /*R angle loc*/LSI->ExplicitTemplateParamsRange.getEnd(),
      LSI->RequiresClause.get());
}
return LSI->GLTemplateParameterList;
239}

241CXXRecordDecl *
242Sema::createLambdaClosureType(SourceRange IntroducerRange, TypeSourceInfo *Info,
                            unsigned LambdaDependencyKind,
                            LambdaCaptureDefault CaptureDefault) {
DeclContext *DC = CurContext;
while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext()))
  DC = DC->getParent();
bool IsGenericLambda = getGenericLambdaTemplateParameterList(getCurLambda(),
                                                             *this);
// Start constructing the lambda class.
CXXRecordDecl *Class = CXXRecordDecl::CreateLambda(
    Context, DC, Info, IntroducerRange.getBegin(), LambdaDependencyKind,
    IsGenericLambda, CaptureDefault);
DC->addDecl(Class);

return Class;
257}

259/// Determine whether the given context is or is enclosed in an inline
260/// function.
261static bool isInInlineFunction(const DeclContext *DC) {
while (!DC->isFileContext()) {
  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(DC))
    if (FD->isInlined())
      return true;

  DC = DC->getLexicalParent();
}

return false;
271}

273std::tuple<MangleNumberingContext *, Decl *>
274Sema::getCurrentMangleNumberContext(const DeclContext *DC) {
// Compute the context for allocating mangling numbers in the current
// expression, if the ABI requires them.
Decl *ManglingContextDecl = ExprEvalContexts.back().ManglingContextDecl;

enum ContextKind {
  Normal,
  DefaultArgument,
  DataMember,
  StaticDataMember,
  InlineVariable,
  VariableTemplate,
  Concept
} Kind = Normal;

// Default arguments of member function parameters that appear in a class
// definition, as well as the initializers of data members, receive special
// treatment. Identify them.
if (ManglingContextDecl) {
  if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(ManglingContextDecl)) {
    if (const DeclContext *LexicalDC
        = Param->getDeclContext()->getLexicalParent())
      if (LexicalDC->isRecord())
        Kind = DefaultArgument;
  } else if (VarDecl *Var = dyn_cast<VarDecl>(ManglingContextDecl)) {
    if (Var->getDeclContext()->isRecord())
      Kind = StaticDataMember;
    else if (Var->getMostRecentDecl()->isInline())
      Kind = InlineVariable;
    else if (Var->getDescribedVarTemplate())
      Kind = VariableTemplate;
    else if (auto *VTS = dyn_cast<VarTemplateSpecializationDecl>(Var)) {
      if (!VTS->isExplicitSpecialization())
        Kind = VariableTemplate;
    }
  } else if (isa<FieldDecl>(ManglingContextDecl)) {
    Kind = DataMember;
  } else if (isa<ImplicitConceptSpecializationDecl>(ManglingContextDecl)) {
    Kind = Concept;
  }
}

// Itanium ABI [5.1.7]:
//   In the following contexts [...] the one-definition rule requires closure
//   types in different translation units to "correspond":
bool IsInNonspecializedTemplate =
    inTemplateInstantiation() || CurContext->isDependentContext();
switch (Kind) {
case Normal: {
  //  -- the bodies of non-exported nonspecialized template functions
  //  -- the bodies of inline functions
  if ((IsInNonspecializedTemplate &&
       !(ManglingContextDecl && isa<ParmVarDecl>(ManglingContextDecl))) ||
      isInInlineFunction(CurContext)) {
    while (auto *CD = dyn_cast<CapturedDecl>(DC))
      DC = CD->getParent();
    return std::make_tuple(&Context.getManglingNumberContext(DC), nullptr);
  }

  return std::make_tuple(nullptr, nullptr);
}

case Concept:
  // Concept definitions aren't code generated and thus aren't mangled,
  // however the ManglingContextDecl is important for the purposes of
  // re-forming the template argument list of the lambda for constraint
  // evaluation.
case StaticDataMember:
  //  -- the initializers of nonspecialized static members of template classes
  if (!IsInNonspecializedTemplate)
    return std::make_tuple(nullptr, ManglingContextDecl);
  // Fall through to get the current context.
  [[fallthrough]];

case DataMember:
  //  -- the in-class initializers of class members
case DefaultArgument:
  //  -- default arguments appearing in class definitions
case InlineVariable:
  //  -- the initializers of inline variables
case VariableTemplate:
  //  -- the initializers of templated variables
  return std::make_tuple(
      &Context.getManglingNumberContext(ASTContext::NeedExtraManglingDecl,
                                        ManglingContextDecl),
      ManglingContextDecl);
}

llvm_unreachable("unexpected context")::llvm::llvm_unreachable_internal("unexpected context", "clang/lib/Sema/SemaLambda.cpp"
, 362);
363}

365CXXMethodDecl *Sema::startLambdaDefinition(
  CXXRecordDecl *Class, SourceRange IntroducerRange,
  TypeSourceInfo *MethodTypeInfo, SourceLocation EndLoc,
  ArrayRef<ParmVarDecl *> Params, ConstexprSpecKind ConstexprKind,
  StorageClass SC, Expr *TrailingRequiresClause) {
QualType MethodType = MethodTypeInfo->getType();
TemplateParameterList *TemplateParams =
    getGenericLambdaTemplateParameterList(getCurLambda(), *this);
// If a lambda appears in a dependent context or is a generic lambda (has
// template parameters) and has an 'auto' return type, deduce it to a
// dependent type.
if (Class->isDependentContext() || TemplateParams) {
  const FunctionProtoType *FPT = MethodType->castAs<FunctionProtoType>();
  QualType Result = FPT->getReturnType();
  if (Result->isUndeducedType()) {
    Result = SubstAutoTypeDependent(Result);
    MethodType = Context.getFunctionType(Result, FPT->getParamTypes(),
                                         FPT->getExtProtoInfo());
  }
}

// C++11 [expr.prim.lambda]p5:
//   The closure type for a lambda-expression has a public inline function
//   call operator (13.5.4) whose parameters and return type are described by
//   the lambda-expression's parameter-declaration-clause and
//   trailing-return-type respectively.
DeclarationName MethodName
  = Context.DeclarationNames.getCXXOperatorName(OO_Call);
DeclarationNameLoc MethodNameLoc =
    DeclarationNameLoc::makeCXXOperatorNameLoc(IntroducerRange);
CXXMethodDecl *Method = CXXMethodDecl::Create(
    Context, Class, EndLoc,
    DeclarationNameInfo(MethodName, IntroducerRange.getBegin(),
                        MethodNameLoc),
    MethodType, MethodTypeInfo, SC, getCurFPFeatures().isFPConstrained(),
    /*isInline=*/true, ConstexprKind, EndLoc, TrailingRequiresClause);
Method->setAccess(AS_public);
if (!TemplateParams)
  Class->addDecl(Method);

// Temporarily set the lexical declaration context to the current
// context, so that the Scope stack matches the lexical nesting.
Method->setLexicalDeclContext(CurContext);
// Create a function template if we have a template parameter list
FunctionTemplateDecl *const TemplateMethod = TemplateParams ?
          FunctionTemplateDecl::Create(Context, Class,
                                       Method->getLocation(), MethodName,
                                       TemplateParams,
                                       Method) : nullptr;
if (TemplateMethod) {
  TemplateMethod->setAccess(AS_public);
  Method->setDescribedFunctionTemplate(TemplateMethod);
  Class->addDecl(TemplateMethod);
  TemplateMethod->setLexicalDeclContext(CurContext);
}

// Add parameters.
if (!Params.empty()) {
  Method->setParams(Params);
  CheckParmsForFunctionDef(Params,
                           /*CheckParameterNames=*/false);

  for (auto *P : Method->parameters())
    P->setOwningFunction(Method);
}

return Method;
432}

434void Sema::handleLambdaNumbering(
  CXXRecordDecl *Class, CXXMethodDecl *Method,
  Optional<std::tuple<bool, unsigned, unsigned, Decl *>> Mangling) {
if (Mangling) {
  bool HasKnownInternalLinkage;
  unsigned ManglingNumber, DeviceManglingNumber;
  Decl *ManglingContextDecl;
  std::tie(HasKnownInternalLinkage, ManglingNumber, DeviceManglingNumber,
           ManglingContextDecl) = *Mangling;
  Class->setLambdaMangling(ManglingNumber, ManglingContextDecl,
                           HasKnownInternalLinkage);
  Class->setDeviceLambdaManglingNumber(DeviceManglingNumber);
  return;
}

auto getMangleNumberingContext =
    [this](CXXRecordDecl *Class,
           Decl *ManglingContextDecl) -> MangleNumberingContext * {
  // Get mangle numbering context if there's any extra decl context.
  if (ManglingContextDecl)
    return &Context.getManglingNumberContext(
        ASTContext::NeedExtraManglingDecl, ManglingContextDecl);
  // Otherwise, from that lambda's decl context.
  auto DC = Class->getDeclContext();
  while (auto *CD = dyn_cast<CapturedDecl>(DC))
    DC = CD->getParent();
  return &Context.getManglingNumberContext(DC);
};

MangleNumberingContext *MCtx;
Decl *ManglingContextDecl;
std::tie(MCtx, ManglingContextDecl) =
    getCurrentMangleNumberContext(Class->getDeclContext());
bool HasKnownInternalLinkage = false;
if (!MCtx && (getLangOpts().CUDA || getLangOpts().SYCLIsDevice ||
              getLangOpts().SYCLIsHost)) {
  // Force lambda numbering in CUDA/HIP as we need to name lambdas following
  // ODR. Both device- and host-compilation need to have a consistent naming
  // on kernel functions. As lambdas are potential part of these `__global__`
  // function names, they needs numbering following ODR.
  // Also force for SYCL, since we need this for the
  // __builtin_sycl_unique_stable_name implementation, which depends on lambda
  // mangling.
  MCtx = getMangleNumberingContext(Class, ManglingContextDecl);
  assert(MCtx && "Retrieving mangle numbering context failed!")(static_cast <bool> (MCtx && "Retrieving mangle numbering context failed!"
) ? void (0) : __assert_fail ("MCtx && \"Retrieving mangle numbering context failed!\""
, "clang/lib/Sema/SemaLambda.cpp", 478, __extension__ __PRETTY_FUNCTION__
));
  HasKnownInternalLinkage = true;
}
if (MCtx) {
  unsigned ManglingNumber = MCtx->getManglingNumber(Method);
  Class->setLambdaMangling(ManglingNumber, ManglingContextDecl,
                           HasKnownInternalLinkage);
  Class->setDeviceLambdaManglingNumber(MCtx->getDeviceManglingNumber(Method));
}
487}

489void Sema::buildLambdaScope(LambdaScopeInfo *LSI,
                                      CXXMethodDecl *CallOperator,
                                      SourceRange IntroducerRange,
                                      LambdaCaptureDefault CaptureDefault,
                                      SourceLocation CaptureDefaultLoc,
                                      bool ExplicitParams,
                                      bool ExplicitResultType,
                                      bool Mutable) {
LSI->CallOperator = CallOperator;
CXXRecordDecl *LambdaClass = CallOperator->getParent();
LSI->Lambda = LambdaClass;
if (CaptureDefault == LCD_ByCopy)
  LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByval;
else if (CaptureDefault == LCD_ByRef)
  LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByref;
LSI->CaptureDefaultLoc = CaptureDefaultLoc;
LSI->IntroducerRange = IntroducerRange;
LSI->ExplicitParams = ExplicitParams;
LSI->Mutable = Mutable;

if (ExplicitResultType) {
  LSI->ReturnType = CallOperator->getReturnType();

  if (!LSI->ReturnType->isDependentType() &&
      !LSI->ReturnType->isVoidType()) {
    if (RequireCompleteType(CallOperator->getBeginLoc(), LSI->ReturnType,
                            diag::err_lambda_incomplete_result)) {
      // Do nothing.
    }
  }
} else {
  LSI->HasImplicitReturnType = true;
}
522}

524void Sema::finishLambdaExplicitCaptures(LambdaScopeInfo *LSI) {
LSI->finishedExplicitCaptures();
526}

528void Sema::ActOnLambdaExplicitTemplateParameterList(SourceLocation LAngleLoc,
                                                  ArrayRef<NamedDecl *> TParams,
                                                  SourceLocation RAngleLoc,
                                                  ExprResult RequiresClause) {
LambdaScopeInfo *LSI = getCurLambda();
assert(LSI && "Expected a lambda scope")(static_cast <bool> (LSI && "Expected a lambda scope"
) ? void (0) : __assert_fail ("LSI && \"Expected a lambda scope\""
, "clang/lib/Sema/SemaLambda.cpp", 533, __extension__ __PRETTY_FUNCTION__
));
assert(LSI->NumExplicitTemplateParams == 0 &&(static_cast <bool> (LSI->NumExplicitTemplateParams ==
&& "Already acted on explicit template parameters"
) ? void (0) : __assert_fail ("LSI->NumExplicitTemplateParams == 0 && \"Already acted on explicit template parameters\""
, "clang/lib/Sema/SemaLambda.cpp", 535, __extension__ __PRETTY_FUNCTION__
))
       "Already acted on explicit template parameters")(static_cast <bool> (LSI->NumExplicitTemplateParams ==
&& "Already acted on explicit template parameters"
) ? void (0) : __assert_fail ("LSI->NumExplicitTemplateParams == 0 && \"Already acted on explicit template parameters\""
, "clang/lib/Sema/SemaLambda.cpp", 535, __extension__ __PRETTY_FUNCTION__
));
assert(LSI->TemplateParams.empty() &&(static_cast <bool> (LSI->TemplateParams.empty() &&
 "Explicit template parameters should come " "before invented (auto) ones"
) ? void (0) : __assert_fail ("LSI->TemplateParams.empty() && \"Explicit template parameters should come \" \"before invented (auto) ones\""
, "clang/lib/Sema/SemaLambda.cpp", 538, __extension__ __PRETTY_FUNCTION__
))
       "Explicit template parameters should come "(static_cast <bool> (LSI->TemplateParams.empty() &&
 "Explicit template parameters should come " "before invented (auto) ones"
) ? void (0) : __assert_fail ("LSI->TemplateParams.empty() && \"Explicit template parameters should come \" \"before invented (auto) ones\""
, "clang/lib/Sema/SemaLambda.cpp", 538, __extension__ __PRETTY_FUNCTION__
))
       "before invented (auto) ones")(static_cast <bool> (LSI->TemplateParams.empty() &&
 "Explicit template parameters should come " "before invented (auto) ones"
) ? void (0) : __assert_fail ("LSI->TemplateParams.empty() && \"Explicit template parameters should come \" \"before invented (auto) ones\""
, "clang/lib/Sema/SemaLambda.cpp", 538, __extension__ __PRETTY_FUNCTION__
));
assert(!TParams.empty() &&(static_cast <bool> (!TParams.empty() && "No template parameters to act on"
) ? void (0) : __assert_fail ("!TParams.empty() && \"No template parameters to act on\""
, "clang/lib/Sema/SemaLambda.cpp", 540, __extension__ __PRETTY_FUNCTION__
))
       "No template parameters to act on")(static_cast <bool> (!TParams.empty() && "No template parameters to act on"
) ? void (0) : __assert_fail ("!TParams.empty() && \"No template parameters to act on\""
, "clang/lib/Sema/SemaLambda.cpp", 540, __extension__ __PRETTY_FUNCTION__
));
LSI->TemplateParams.append(TParams.begin(), TParams.end());
LSI->NumExplicitTemplateParams = TParams.size();
LSI->ExplicitTemplateParamsRange = {LAngleLoc, RAngleLoc};
LSI->RequiresClause = RequiresClause;
545}

547void Sema::addLambdaParameters(
  ArrayRef<LambdaIntroducer::LambdaCapture> Captures,
  CXXMethodDecl *CallOperator, Scope *CurScope) {
// Introduce our parameters into the function scope
for (unsigned p = 0, NumParams = CallOperator->getNumParams();
     p < NumParams; ++p) {
  ParmVarDecl *Param = CallOperator->getParamDecl(p);

  // If this has an identifier, add it to the scope stack.
  if (CurScope && Param->getIdentifier()) {
    bool Error = false;
    // Resolution of CWG 2211 in C++17 renders shadowing ill-formed, but we
    // retroactively apply it.
    for (const auto &Capture : Captures) {
      if (Capture.Id == Param->getIdentifier()) {
        Error = true;
        Diag(Param->getLocation(), diag::err_parameter_shadow_capture);
        Diag(Capture.Loc, diag::note_var_explicitly_captured_here)
            << Capture.Id << true;
      }
    }
    if (!Error)
      CheckShadow(CurScope, Param);

    PushOnScopeChains(Param, CurScope);
  }
}
574}

576/// If this expression is an enumerator-like expression of some type
577/// T, return the type T; otherwise, return null.
578///
579/// Pointer comparisons on the result here should always work because
580/// it's derived from either the parent of an EnumConstantDecl
581/// (i.e. the definition) or the declaration returned by
582/// EnumType::getDecl() (i.e. the definition).
583static EnumDecl *findEnumForBlockReturn(Expr *E) {
// An expression is an enumerator-like expression of type T if,
// ignoring parens and parens-like expressions:
E = E->IgnoreParens();

//  - it is an enumerator whose enum type is T or
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
  if (EnumConstantDecl *D
        = dyn_cast<EnumConstantDecl>(DRE->getDecl())) {
    return cast<EnumDecl>(D->getDeclContext());
  }
  return nullptr;
}

//  - it is a comma expression whose RHS is an enumerator-like
//    expression of type T or
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
  if (BO->getOpcode() == BO_Comma)
    return findEnumForBlockReturn(BO->getRHS());
  return nullptr;
}

//  - it is a statement-expression whose value expression is an
//    enumerator-like expression of type T or
if (StmtExpr *SE = dyn_cast<StmtExpr>(E)) {
  if (Expr *last = dyn_cast_or_null<Expr>(SE->getSubStmt()->body_back()))
    return findEnumForBlockReturn(last);
  return nullptr;
}

//   - it is a ternary conditional operator (not the GNU ?:
//     extension) whose second and third operands are
//     enumerator-like expressions of type T or
if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
  if (EnumDecl *ED = findEnumForBlockReturn(CO->getTrueExpr()))
    if (ED == findEnumForBlockReturn(CO->getFalseExpr()))
      return ED;
  return nullptr;
}

// (implicitly:)
//   - it is an implicit integral conversion applied to an
//     enumerator-like expression of type T or
if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
  // We can sometimes see integral conversions in valid
  // enumerator-like expressions.
  if (ICE->getCastKind() == CK_IntegralCast)
    return findEnumForBlockReturn(ICE->getSubExpr());

  // Otherwise, just rely on the type.
}

//   - it is an expression of that formal enum type.
if (const EnumType *ET = E->getType()->getAs<EnumType>()) {
  return ET->getDecl();
}

// Otherwise, nope.
return nullptr;
642}

644/// Attempt to find a type T for which the returned expression of the
645/// given statement is an enumerator-like expression of that type.
646static EnumDecl *findEnumForBlockReturn(ReturnStmt *ret) {
if (Expr *retValue = ret->getRetValue())
  return findEnumForBlockReturn(retValue);
return nullptr;
650}

652/// Attempt to find a common type T for which all of the returned
653/// expressions in a block are enumerator-like expressions of that
654/// type.
655static EnumDecl *findCommonEnumForBlockReturns(ArrayRef<ReturnStmt*> returns) {
ArrayRef<ReturnStmt*>::iterator i = returns.begin(), e = returns.end();

// Try to find one for the first return.
EnumDecl *ED = findEnumForBlockReturn(*i);
if (!ED) return nullptr;

// Check that the rest of the returns have the same enum.
for (++i; i != e; ++i) {
  if (findEnumForBlockReturn(*i) != ED)
    return nullptr;
}

// Never infer an anonymous enum type.
if (!ED->hasNameForLinkage()) return nullptr;

return ED;
672}

674/// Adjust the given return statements so that they formally return
675/// the given type.  It should require, at most, an IntegralCast.
676static void adjustBlockReturnsToEnum(Sema &S, ArrayRef<ReturnStmt*> returns,
                                   QualType returnType) {
for (ArrayRef<ReturnStmt*>::iterator
       i = returns.begin(), e = returns.end(); i != e; ++i) {
  ReturnStmt *ret = *i;
  Expr *retValue = ret->getRetValue();
  if (S.Context.hasSameType(retValue->getType(), returnType))
    continue;

  // Right now we only support integral fixup casts.
  assert(returnType->isIntegralOrUnscopedEnumerationType())(static_cast <bool> (returnType->isIntegralOrUnscopedEnumerationType
()) ? void (0) : __assert_fail ("returnType->isIntegralOrUnscopedEnumerationType()"
, "clang/lib/Sema/SemaLambda.cpp", 686, __extension__ __PRETTY_FUNCTION__
));
  assert(retValue->getType()->isIntegralOrUnscopedEnumerationType())(static_cast <bool> (retValue->getType()->isIntegralOrUnscopedEnumerationType
()) ? void (0) : __assert_fail ("retValue->getType()->isIntegralOrUnscopedEnumerationType()"
, "clang/lib/Sema/SemaLambda.cpp", 687, __extension__ __PRETTY_FUNCTION__
));

  ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(retValue);

  Expr *E = (cleanups ? cleanups->getSubExpr() : retValue);
  E = ImplicitCastExpr::Create(S.Context, returnType, CK_IntegralCast, E,
                               /*base path*/ nullptr, VK_PRValue,
                               FPOptionsOverride());
  if (cleanups) {
    cleanups->setSubExpr(E);
  } else {
    ret->setRetValue(E);
  }
}
701}

703void Sema::deduceClosureReturnType(CapturingScopeInfo &CSI) {
assert(CSI.HasImplicitReturnType)(static_cast <bool> (CSI.HasImplicitReturnType) ? void (
0) : __assert_fail ("CSI.HasImplicitReturnType", "clang/lib/Sema/SemaLambda.cpp"
, 704, __extension__ __PRETTY_FUNCTION__));
// If it was ever a placeholder, it had to been deduced to DependentTy.
assert(CSI.ReturnType.isNull() || !CSI.ReturnType->isUndeducedType())(static_cast <bool> (CSI.ReturnType.isNull() || !CSI.ReturnType
->isUndeducedType()) ? void (0) : __assert_fail ("CSI.ReturnType.isNull() || !CSI.ReturnType->isUndeducedType()"
, "clang/lib/Sema/SemaLambda.cpp", 706, __extension__ __PRETTY_FUNCTION__
));
assert((!isa<LambdaScopeInfo>(CSI) || !getLangOpts().CPlusPlus14) &&(static_cast <bool> ((!isa<LambdaScopeInfo>(CSI) ||
 !getLangOpts().CPlusPlus14) && "lambda expressions use auto deduction in C++14 onwards"
) ? void (0) : __assert_fail ("(!isa<LambdaScopeInfo>(CSI) || !getLangOpts().CPlusPlus14) && \"lambda expressions use auto deduction in C++14 onwards\""
, "clang/lib/Sema/SemaLambda.cpp", 708, __extension__ __PRETTY_FUNCTION__
))
       "lambda expressions use auto deduction in C++14 onwards")(static_cast <bool> ((!isa<LambdaScopeInfo>(CSI) ||
 !getLangOpts().CPlusPlus14) && "lambda expressions use auto deduction in C++14 onwards"
) ? void (0) : __assert_fail ("(!isa<LambdaScopeInfo>(CSI) || !getLangOpts().CPlusPlus14) && \"lambda expressions use auto deduction in C++14 onwards\""
, "clang/lib/Sema/SemaLambda.cpp", 708, __extension__ __PRETTY_FUNCTION__
));

// C++ core issue 975:
//   If a lambda-expression does not include a trailing-return-type,
//   it is as if the trailing-return-type denotes the following type:
//     - if there are no return statements in the compound-statement,
//       or all return statements return either an expression of type
//       void or no expression or braced-init-list, the type void;
//     - otherwise, if all return statements return an expression
//       and the types of the returned expressions after
//       lvalue-to-rvalue conversion (4.1 [conv.lval]),
//       array-to-pointer conversion (4.2 [conv.array]), and
//       function-to-pointer conversion (4.3 [conv.func]) are the
//       same, that common type;
//     - otherwise, the program is ill-formed.
//
// C++ core issue 1048 additionally removes top-level cv-qualifiers
// from the types of returned expressions to match the C++14 auto
// deduction rules.
//
// In addition, in blocks in non-C++ modes, if all of the return
// statements are enumerator-like expressions of some type T, where
// T has a name for linkage, then we infer the return type of the
// block to be that type.

// First case: no return statements, implicit void return type.
ASTContext &Ctx = getASTContext();
if (CSI.Returns.empty()) {
  // It's possible there were simply no /valid/ return statements.
  // In this case, the first one we found may have at least given us a type.
  if (CSI.ReturnType.isNull())
    CSI.ReturnType = Ctx.VoidTy;
  return;
}

// Second case: at least one return statement has dependent type.
// Delay type checking until instantiation.
assert(!CSI.ReturnType.isNull() && "We should have a tentative return type.")(static_cast <bool> (!CSI.ReturnType.isNull() &&
 "We should have a tentative return type.") ? void (0) : __assert_fail
 ("!CSI.ReturnType.isNull() && \"We should have a tentative return type.\""
, "clang/lib/Sema/SemaLambda.cpp", 745, __extension__ __PRETTY_FUNCTION__
));
if (CSI.ReturnType->isDependentType())
  return;

// Try to apply the enum-fuzz rule.
if (!getLangOpts().CPlusPlus) {
  assert(isa<BlockScopeInfo>(CSI))(static_cast <bool> (isa<BlockScopeInfo>(CSI)) ? void
 (0) : __assert_fail ("isa<BlockScopeInfo>(CSI)", "clang/lib/Sema/SemaLambda.cpp"
, 751, __extension__ __PRETTY_FUNCTION__));
  const EnumDecl *ED = findCommonEnumForBlockReturns(CSI.Returns);
  if (ED) {
    CSI.ReturnType = Context.getTypeDeclType(ED);
    adjustBlockReturnsToEnum(*this, CSI.Returns, CSI.ReturnType);
    return;
  }
}

// Third case: only one return statement. Don't bother doing extra work!
if (CSI.Returns.size() == 1)
  return;

// General case: many return statements.
// Check that they all have compatible return types.

// We require the return types to strictly match here.
// Note that we've already done the required promotions as part of
// processing the return statement.
for (const ReturnStmt *RS : CSI.Returns) {
  const Expr *RetE = RS->getRetValue();

  QualType ReturnType =
      (RetE ? RetE->getType() : Context.VoidTy).getUnqualifiedType();
  if (Context.getCanonicalFunctionResultType(ReturnType) ==
        Context.getCanonicalFunctionResultType(CSI.ReturnType)) {
    // Use the return type with the strictest possible nullability annotation.
    auto RetTyNullability = ReturnType->getNullability();
    auto BlockNullability = CSI.ReturnType->getNullability();
    if (BlockNullability &&
        (!RetTyNullability ||
         hasWeakerNullability(*RetTyNullability, *BlockNullability)))
      CSI.ReturnType = ReturnType;
    continue;
  }

  // FIXME: This is a poor diagnostic for ReturnStmts without expressions.
  // TODO: It's possible that the *first* return is the divergent one.
  Diag(RS->getBeginLoc(),
       diag::err_typecheck_missing_return_type_incompatible)
      << ReturnType << CSI.ReturnType << isa<LambdaScopeInfo>(CSI);
  // Continue iterating so that we keep emitting diagnostics.
}
794}

796QualType Sema::buildLambdaInitCaptureInitialization(
  SourceLocation Loc, bool ByRef, SourceLocation EllipsisLoc,
  Optional<unsigned> NumExpansions, IdentifierInfo *Id, bool IsDirectInit,
  Expr *&Init) {
// Create an 'auto' or 'auto&' TypeSourceInfo that we can use to
// deduce against.
QualType DeductType = Context.getAutoDeductType();
TypeLocBuilder TLB;
AutoTypeLoc TL = TLB.push<AutoTypeLoc>(DeductType);
TL.setNameLoc(Loc);
if (ByRef) {
  DeductType = BuildReferenceType(DeductType, true, Loc, Id);
  assert(!DeductType.isNull() && "can't build reference to auto")(static_cast <bool> (!DeductType.isNull() && "can't build reference to auto"
) ? void (0) : __assert_fail ("!DeductType.isNull() && \"can't build reference to auto\""
, "clang/lib/Sema/SemaLambda.cpp", 808, __extension__ __PRETTY_FUNCTION__
));
  TLB.push<ReferenceTypeLoc>(DeductType).setSigilLoc(Loc);
}
if (EllipsisLoc.isValid()) {
  if (Init->containsUnexpandedParameterPack()) {
    Diag(EllipsisLoc, getLangOpts().CPlusPlus20
                          ? diag::warn_cxx17_compat_init_capture_pack
                          : diag::ext_init_capture_pack);
    DeductType = Context.getPackExpansionType(DeductType, NumExpansions,
                                              /*ExpectPackInType=*/false);
    TLB.push<PackExpansionTypeLoc>(DeductType).setEllipsisLoc(EllipsisLoc);
  } else {
    // Just ignore the ellipsis for now and form a non-pack variable. We'll
    // diagnose this later when we try to capture it.
  }
}
TypeSourceInfo *TSI = TLB.getTypeSourceInfo(Context, DeductType);

// Deduce the type of the init capture.
QualType DeducedType = deduceVarTypeFromInitializer(
    /*VarDecl*/nullptr, DeclarationName(Id), DeductType, TSI,
    SourceRange(Loc, Loc), IsDirectInit, Init);
if (DeducedType.isNull())
  return QualType();

// Are we a non-list direct initialization?
ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);

// Perform initialization analysis and ensure any implicit conversions
// (such as lvalue-to-rvalue) are enforced.
InitializedEntity Entity =
    InitializedEntity::InitializeLambdaCapture(Id, DeducedType, Loc);
InitializationKind Kind =
    IsDirectInit
        ? (CXXDirectInit ? InitializationKind::CreateDirect(
                               Loc, Init->getBeginLoc(), Init->getEndLoc())
                         : InitializationKind::CreateDirectList(Loc))
        : InitializationKind::CreateCopy(Loc, Init->getBeginLoc());

MultiExprArg Args = Init;
if (CXXDirectInit)
  Args =
      MultiExprArg(CXXDirectInit->getExprs(), CXXDirectInit->getNumExprs());
QualType DclT;
InitializationSequence InitSeq(*this, Entity, Kind, Args);
ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);

if (Result.isInvalid())
  return QualType();

Init = Result.getAs<Expr>();
return DeducedType;
860}

862VarDecl *Sema::createLambdaInitCaptureVarDecl(SourceLocation Loc,
                                            QualType InitCaptureType,
                                            SourceLocation EllipsisLoc,
                                            IdentifierInfo *Id,
                                            unsigned InitStyle, Expr *Init) {
// FIXME: Retain the TypeSourceInfo from buildLambdaInitCaptureInitialization
// rather than reconstructing it here.
TypeSourceInfo *TSI = Context.getTrivialTypeSourceInfo(InitCaptureType, Loc);
if (auto PETL = TSI->getTypeLoc().getAs<PackExpansionTypeLoc>())
  PETL.setEllipsisLoc(EllipsisLoc);

// Create a dummy variable representing the init-capture. This is not actually
// used as a variable, and only exists as a way to name and refer to the
// init-capture.
// FIXME: Pass in separate source locations for '&' and identifier.
VarDecl *NewVD = VarDecl::Create(Context, CurContext, Loc,
                                 Loc, Id, InitCaptureType, TSI, SC_Auto);
NewVD->setInitCapture(true);
NewVD->setReferenced(true);
// FIXME: Pass in a VarDecl::InitializationStyle.
NewVD->setInitStyle(static_cast<VarDecl::InitializationStyle>(InitStyle));
NewVD->markUsed(Context);
NewVD->setInit(Init);
if (NewVD->isParameterPack())
  getCurLambda()->LocalPacks.push_back(NewVD);
return NewVD;
888}

890void Sema::addInitCapture(LambdaScopeInfo *LSI, VarDecl *Var,
                        bool isReferenceType) {
assert(Var->isInitCapture() && "init capture flag should be set")(static_cast <bool> (Var->isInitCapture() &&
 "init capture flag should be set") ? void (0) : __assert_fail
 ("Var->isInitCapture() && \"init capture flag should be set\""
, "clang/lib/Sema/SemaLambda.cpp", 892, __extension__ __PRETTY_FUNCTION__
));
LSI->addCapture(Var, /*isBlock*/ false, isReferenceType,
                /*isNested*/ false, Var->getLocation(), SourceLocation(),
                Var->getType(), /*Invalid*/ false);
896}

898void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
                                      Declarator &ParamInfo,
                                      Scope *CurScope) {
LambdaScopeInfo *const LSI = getCurLambda();
assert(LSI && "LambdaScopeInfo should be on stack!")(static_cast <bool> (LSI && "LambdaScopeInfo should be on stack!"
) ? void (0) : __assert_fail ("LSI && \"LambdaScopeInfo should be on stack!\""
, "clang/lib/Sema/SemaLambda.cpp", 902, __extension__ __PRETTY_FUNCTION__
));
1
Assuming 'LSI' is non-null→
2
←
'?' condition is true→

// Determine if we're within a context where we know that the lambda will
// be dependent, because there are template parameters in scope.
CXXRecordDecl::LambdaDependencyKind LambdaDependencyKind =
    CXXRecordDecl::LDK_Unknown;
if (LSI->NumExplicitTemplateParams > 0) {
3
←
Assuming field 'NumExplicitTemplateParams' is <= 0→
4
←
Taking false branch→
  auto *TemplateParamScope = CurScope->getTemplateParamParent();
  assert(TemplateParamScope &&(static_cast <bool> (TemplateParamScope && "Lambda with explicit template param list should establish a "
 "template param scope") ? void (0) : __assert_fail ("TemplateParamScope && \"Lambda with explicit template param list should establish a \" \"template param scope\""
, "clang/lib/Sema/SemaLambda.cpp", 912, __extension__ __PRETTY_FUNCTION__
))
         "Lambda with explicit template param list should establish a "(static_cast <bool> (TemplateParamScope && "Lambda with explicit template param list should establish a "
 "template param scope") ? void (0) : __assert_fail ("TemplateParamScope && \"Lambda with explicit template param list should establish a \" \"template param scope\""
, "clang/lib/Sema/SemaLambda.cpp", 912, __extension__ __PRETTY_FUNCTION__
))
         "template param scope")(static_cast <bool> (TemplateParamScope && "Lambda with explicit template param list should establish a "
 "template param scope") ? void (0) : __assert_fail ("TemplateParamScope && \"Lambda with explicit template param list should establish a \" \"template param scope\""
, "clang/lib/Sema/SemaLambda.cpp", 912, __extension__ __PRETTY_FUNCTION__
));
  assert(TemplateParamScope->getParent())(static_cast <bool> (TemplateParamScope->getParent()
) ? void (0) : __assert_fail ("TemplateParamScope->getParent()"
, "clang/lib/Sema/SemaLambda.cpp", 913, __extension__ __PRETTY_FUNCTION__
));
  if (TemplateParamScope->getParent()->getTemplateParamParent() != nullptr)
    LambdaDependencyKind = CXXRecordDecl::LDK_AlwaysDependent;
} else if (CurScope->getTemplateParamParent() != nullptr) {
5
←
Assuming the condition is false→
6
←
Taking false branch→
  LambdaDependencyKind = CXXRecordDecl::LDK_AlwaysDependent;
}

// Determine the signature of the call operator.
TypeSourceInfo *MethodTyInfo;
bool ExplicitParams = true;
bool ExplicitResultType = true;
bool ContainsUnexpandedParameterPack = false;
SourceLocation EndLoc;
SmallVector<ParmVarDecl *, 8> Params;

assert((static_cast <bool> ((ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_static) && "Unexpected storage specifier"
) ? void (0) : __assert_fail ("(ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static) && \"Unexpected storage specifier\""
, "clang/lib/Sema/SemaLambda.cpp", 932, __extension__ __PRETTY_FUNCTION__
))
7
←
Assuming the condition is false→
8
←
Assuming the condition is true→
9
←
'?' condition is true→
    (ParamInfo.getDeclSpec().getStorageClassSpec() ==(static_cast <bool> ((ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_static) && "Unexpected storage specifier"
) ? void (0) : __assert_fail ("(ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static) && \"Unexpected storage specifier\""
, "clang/lib/Sema/SemaLambda.cpp", 932, __extension__ __PRETTY_FUNCTION__
))
         DeclSpec::SCS_unspecified ||(static_cast <bool> ((ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_static) && "Unexpected storage specifier"
) ? void (0) : __assert_fail ("(ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static) && \"Unexpected storage specifier\""
, "clang/lib/Sema/SemaLambda.cpp", 932, __extension__ __PRETTY_FUNCTION__
))
     ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static) &&(static_cast <bool> ((ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_static) && "Unexpected storage specifier"
) ? void (0) : __assert_fail ("(ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static) && \"Unexpected storage specifier\""
, "clang/lib/Sema/SemaLambda.cpp", 932, __extension__ __PRETTY_FUNCTION__
))
    "Unexpected storage specifier")(static_cast <bool> ((ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec
() == DeclSpec::SCS_static) && "Unexpected storage specifier"
) ? void (0) : __assert_fail ("(ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_unspecified || ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static) && \"Unexpected storage specifier\""
, "clang/lib/Sema/SemaLambda.cpp", 932, __extension__ __PRETTY_FUNCTION__
));
bool IsLambdaStatic =
    ParamInfo.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static;

if (ParamInfo.getNumTypeObjects() == 0) {
10
←
Assuming the condition is true→
11
←
Taking true branch→
  // C++11 [expr.prim.lambda]p4:
  //   If a lambda-expression does not include a lambda-declarator, it is as
  //   if the lambda-declarator were ().
  FunctionProtoType::ExtProtoInfo EPI(Context.getDefaultCallingConvention(
      /*IsVariadic=*/false, /*IsCXXMethod=*/true));
  EPI.HasTrailingReturn = true;
  EPI.TypeQuals.addConst();
  LangAS AS = getDefaultCXXMethodAddrSpace();
  if (AS != LangAS::Default)
12
←
Assuming 'AS' is equal to Default→
    EPI.TypeQuals.addAddressSpace(AS);

  // C++1y [expr.prim.lambda]:
  //   The lambda return type is 'auto', which is replaced by the
  //   trailing-return type if provided and/or deduced from 'return'
  //   statements
  // We don't do this before C++1y, because we don't support deduced return
  // types there.
  QualType DefaultTypeForNoTrailingReturn =
13
←
Taking false branch→
      getLangOpts().CPlusPlus14 ? Context.getAutoDeductType()
14
←
Assuming field 'CPlusPlus14' is 0→
15
←
'?' condition is false→
                                : Context.DependentTy;
  QualType MethodTy = Context.getFunctionType(DefaultTypeForNoTrailingReturn,
                                              std::nullopt, EPI);
  MethodTyInfo = Context.getTrivialTypeSourceInfo(MethodTy);
  ExplicitParams = false;
  ExplicitResultType = false;
  EndLoc = Intro.Range.getEnd();
} else {
  assert(ParamInfo.isFunctionDeclarator() &&(static_cast <bool> (ParamInfo.isFunctionDeclarator() &&
 "lambda-declarator is a function") ? void (0) : __assert_fail
 ("ParamInfo.isFunctionDeclarator() && \"lambda-declarator is a function\""
, "clang/lib/Sema/SemaLambda.cpp", 965, __extension__ __PRETTY_FUNCTION__
))
         "lambda-declarator is a function")(static_cast <bool> (ParamInfo.isFunctionDeclarator() &&
 "lambda-declarator is a function") ? void (0) : __assert_fail
 ("ParamInfo.isFunctionDeclarator() && \"lambda-declarator is a function\""
, "clang/lib/Sema/SemaLambda.cpp", 965, __extension__ __PRETTY_FUNCTION__
));
  DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getFunctionTypeInfo();

  // C++11 [expr.prim.lambda]p5:
  //   This function call operator is declared const (9.3.1) if and only if
  //   the lambda-expression's parameter-declaration-clause is not followed
  //   by mutable. It is neither virtual nor declared volatile. [...]
  if (!FTI.hasMutableQualifier() && !IsLambdaStatic) {
    FTI.getOrCreateMethodQualifiers().SetTypeQual(DeclSpec::TQ_const,
                                                  SourceLocation());
  }

  MethodTyInfo = GetTypeForDeclarator(ParamInfo, CurScope);
  assert(MethodTyInfo && "no type from lambda-declarator")(static_cast <bool> (MethodTyInfo && "no type from lambda-declarator"
) ? void (0) : __assert_fail ("MethodTyInfo && \"no type from lambda-declarator\""
, "clang/lib/Sema/SemaLambda.cpp", 978, __extension__ __PRETTY_FUNCTION__
));
  EndLoc = ParamInfo.getSourceRange().getEnd();

  ExplicitResultType = FTI.hasTrailingReturnType();

  if (ExplicitResultType && getLangOpts().HLSL) {
    QualType RetTy = FTI.getTrailingReturnType().get();
    if (!RetTy.isNull()) {
      // HLSL does not support specifying an address space on a lambda return
      // type.
      LangAS AddressSpace = RetTy.getAddressSpace();
      if (AddressSpace != LangAS::Default)
        Diag(FTI.getTrailingReturnTypeLoc(),
             diag::err_return_value_with_address_space);
    }
  }

  if (FTIHasNonVoidParameters(FTI)) {
    Params.reserve(FTI.NumParams);
    for (unsigned i = 0, e = FTI.NumParams; i != e; ++i)
      Params.push_back(cast<ParmVarDecl>(FTI.Params[i].Param));
  }

  // Check for unexpanded parameter packs in the method type.
  if (MethodTyInfo->getType()->containsUnexpandedParameterPack())
    DiagnoseUnexpandedParameterPack(Intro.Range.getBegin(), MethodTyInfo,
                                    UPPC_DeclarationType);
}

CXXRecordDecl *Class = createLambdaClosureType(
    Intro.Range, MethodTyInfo, LambdaDependencyKind, Intro.Default);
CXXMethodDecl *Method =
    startLambdaDefinition(Class, Intro.Range, MethodTyInfo, EndLoc, Params,
                          ParamInfo.getDeclSpec().getConstexprSpecifier(),
                          IsLambdaStatic15.1
'IsLambdaStatic' is true
 ? SC_Static : SC_None,
16
←
'?' condition is true→
                          ParamInfo.getTrailingRequiresClause());
if (ExplicitParams16.1
'ExplicitParams' is false
)
17
←
Taking false branch→
  CheckCXXDefaultArguments(Method);

// This represents the function body for the lambda function, check if we
// have to apply optnone due to a pragma.
AddRangeBasedOptnone(Method);

// code_seg attribute on lambda apply to the method.
if (Attr *A = getImplicitCodeSegOrSectionAttrForFunction(Method, /*IsDefinition=*/true))
18
←
Assuming 'A' is null→
19
←
Taking false branch→
  Method->addAttr(A);

// Attributes on the lambda apply to the method.
ProcessDeclAttributes(CurScope, Method, ParamInfo);

// CUDA lambdas get implicit host and device attributes.
if (getLangOpts().CUDA)
20
←
Assuming field 'CUDA' is 0→
21
←
Taking false branch→
  CUDASetLambdaAttrs(Method);

// OpenMP lambdas might get assumumption attributes.
if (LangOpts.OpenMP)
22
←
Assuming field 'OpenMP' is 0→
23
←
Taking false branch→
  ActOnFinishedFunctionDefinitionInOpenMPAssumeScope(Method);

// Number the lambda for linkage purposes if necessary.
handleLambdaNumbering(Class, Method);

// Introduce the function call operator as the current declaration context.
PushDeclContext(CurScope, Method);

// Build the lambda scope.
buildLambdaScope(LSI, Method, Intro.Range, Intro.Default, Intro.DefaultLoc,
                 ExplicitParams, ExplicitResultType, !Method->isConst());

// C++11 [expr.prim.lambda]p9:
//   A lambda-expression whose smallest enclosing scope is a block scope is a
//   local lambda expression; any other lambda expression shall not have a
//   capture-default or simple-capture in its lambda-introducer.
//
// For simple-captures, this is covered by the check below that any named
// entity is a variable that can be captured.
//
// For DR1632, we also allow a capture-default in any context where we can
// odr-use 'this' (in particular, in a default initializer for a non-static
// data member).
if (Intro.Default != LCD_None && !Class->getParent()->isFunctionOrMethod() &&
24
←
Assuming field 'Default' is equal to LCD_None→
25
←
Taking false branch→
    (getCurrentThisType().isNull() ||
     CheckCXXThisCapture(SourceLocation(), /*Explicit*/true,
                         /*BuildAndDiagnose*/false)))
  Diag(Intro.DefaultLoc, diag::err_capture_default_non_local);

// Distinct capture names, for diagnostics.
llvm::SmallSet<IdentifierInfo*, 8> CaptureNames;

// Handle explicit captures.
SourceLocation PrevCaptureLoc
  = Intro.Default25.1
Field 'Default' is equal to LCD_None
 == LCD_None? Intro.Range.getBegin() : Intro.DefaultLoc;
26
←
'?' condition is true→
for (auto C = Intro.Captures.begin(), E = Intro.Captures.end(); C != E;
27
←
Assuming 'C' is not equal to 'E'→
     PrevCaptureLoc = C->Loc, ++C) {
  if (C->Kind == LCK_This || C->Kind == LCK_StarThis) {
28
←
Assuming field 'Kind' is not equal to LCK_This→
29
←
Assuming field 'Kind' is not equal to LCK_StarThis→
    if (C->Kind == LCK_StarThis)
      Diag(C->Loc, !getLangOpts().CPlusPlus17
                           ? diag::ext_star_this_lambda_capture_cxx17
                           : diag::warn_cxx14_compat_star_this_lambda_capture);

    // C++11 [expr.prim.lambda]p8:
    //   An identifier or this shall not appear more than once in a
    //   lambda-capture.
    if (LSI->isCXXThisCaptured()) {
      Diag(C->Loc, diag::err_capture_more_than_once)
          << "'this'" << SourceRange(LSI->getCXXThisCapture().getLocation())
          << FixItHint::CreateRemoval(
                 SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
      continue;
    }

    // C++2a [expr.prim.lambda]p8:
    //  If a lambda-capture includes a capture-default that is =,
    //  each simple-capture of that lambda-capture shall be of the form
    //  "&identifier", "this", or "* this". [ Note: The form [&,this] is
    //  redundant but accepted for compatibility with ISO C++14. --end note ]
    if (Intro.Default == LCD_ByCopy && C->Kind != LCK_StarThis)
      Diag(C->Loc, !getLangOpts().CPlusPlus20
                       ? diag::ext_equals_this_lambda_capture_cxx20
                       : diag::warn_cxx17_compat_equals_this_lambda_capture);

    // C++11 [expr.prim.lambda]p12:
    //   If this is captured by a local lambda expression, its nearest
    //   enclosing function shall be a non-static member function.
    QualType ThisCaptureType = getCurrentThisType();
    if (ThisCaptureType.isNull()) {
      Diag(C->Loc, diag::err_this_capture) << true;
      continue;
    }

    CheckCXXThisCapture(C->Loc, /*Explicit=*/true, /*BuildAndDiagnose*/ true,
                        /*FunctionScopeIndexToStopAtPtr*/ nullptr,
                        C->Kind == LCK_StarThis);
    if (!LSI->Captures.empty())
      LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange;
    continue;
  }

  assert(C->Id && "missing identifier for capture")(static_cast <bool> (C->Id && "missing identifier for capture"
) ? void (0) : __assert_fail ("C->Id && \"missing identifier for capture\""
, "clang/lib/Sema/SemaLambda.cpp", 1115, __extension__ __PRETTY_FUNCTION__
));
30
←
Taking false branch→
31
←
Assuming field 'Id' is non-null→
32
←
'?' condition is true→

  if (C->Init.isInvalid())
33
←
Assuming the condition is false→
34
←
Taking false branch→
    continue;

  ValueDecl *Var = nullptr;
  if (C->Init.isUsable()) {
    Diag(C->Loc, getLangOpts().CPlusPlus14
                     ? diag::warn_cxx11_compat_init_capture
                     : diag::ext_init_capture);

    // If the initializer expression is usable, but the InitCaptureType
    // is not, then an error has occurred - so ignore the capture for now.
    // for e.g., [n{0}] { }; <-- if no <initializer_list> is included.
    // FIXME: we should create the init capture variable and mark it invalid
    // in this case.
    if (C->InitCaptureType.get().isNull())
      continue;

    if (C->Init.get()->containsUnexpandedParameterPack() &&
        !C->InitCaptureType.get()->getAs<PackExpansionType>())
      DiagnoseUnexpandedParameterPack(C->Init.get(), UPPC_Initializer);

    unsigned InitStyle;
    switch (C->InitKind) {
    case LambdaCaptureInitKind::NoInit:
      llvm_unreachable("not an init-capture?")::llvm::llvm_unreachable_internal("not an init-capture?", "clang/lib/Sema/SemaLambda.cpp"
, 1141);
    case LambdaCaptureInitKind::CopyInit:
      InitStyle = VarDecl::CInit;
      break;
    case LambdaCaptureInitKind::DirectInit:
      InitStyle = VarDecl::CallInit;
      break;
    case LambdaCaptureInitKind::ListInit:
      InitStyle = VarDecl::ListInit;
      break;
    }
    Var = createLambdaInitCaptureVarDecl(C->Loc, C->InitCaptureType.get(),
                                         C->EllipsisLoc, C->Id, InitStyle,
                                         C->Init.get());
    // C++1y [expr.prim.lambda]p11:
    //   An init-capture behaves as if it declares and explicitly
    //   captures a variable [...] whose declarative region is the
    //   lambda-expression's compound-statement
    if (Var)
      PushOnScopeChains(Var, CurScope, false);
  } else {
    assert(C->InitKind == LambdaCaptureInitKind::NoInit &&(static_cast <bool> (C->InitKind == LambdaCaptureInitKind
::NoInit && "init capture has valid but null init?") ?
 void (0) : __assert_fail ("C->InitKind == LambdaCaptureInitKind::NoInit && \"init capture has valid but null init?\""
, "clang/lib/Sema/SemaLambda.cpp", 1163, __extension__ __PRETTY_FUNCTION__
))
35
←
Taking false branch→
36
←
Assuming field 'InitKind' is equal to NoInit→
37
←
'?' condition is true→
           "init capture has valid but null init?")(static_cast <bool> (C->InitKind == LambdaCaptureInitKind
::NoInit && "init capture has valid but null init?") ?
 void (0) : __assert_fail ("C->InitKind == LambdaCaptureInitKind::NoInit && \"init capture has valid but null init?\""
, "clang/lib/Sema/SemaLambda.cpp", 1163, __extension__ __PRETTY_FUNCTION__
));

    // C++11 [expr.prim.lambda]p8:
    //   If a lambda-capture includes a capture-default that is &, the
    //   identifiers in the lambda-capture shall not be preceded by &.
    //   If a lambda-capture includes a capture-default that is =, [...]
    //   each identifier it contains shall be preceded by &.
    if (C->Kind == LCK_ByRef && Intro.Default == LCD_ByRef) {
38
←
Assuming field 'Kind' is not equal to LCK_ByRef→
      Diag(C->Loc, diag::err_reference_capture_with_reference_default)
          << FixItHint::CreateRemoval(
              SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
      continue;
    } else if (C->Kind == LCK_ByCopy && Intro.Default == LCD_ByCopy) {
39
←
Assuming field 'Kind' is not equal to LCK_ByCopy→
      Diag(C->Loc, diag::err_copy_capture_with_copy_default)
          << FixItHint::CreateRemoval(
              SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
      continue;
    }

    // C++11 [expr.prim.lambda]p10:
    //   The identifiers in a capture-list are looked up using the usual
    //   rules for unqualified name lookup (3.4.1)
    DeclarationNameInfo Name(C->Id, C->Loc);
    LookupResult R(*this, Name, LookupOrdinaryName);
    LookupName(R, CurScope);
    if (R.isAmbiguous())
40
←
Assuming the condition is false→
41
←
Taking false branch→
      continue;
    if (R.empty()) {
42
←
Assuming the condition is false→
43
←
Taking false branch→
      // FIXME: Disable corrections that would add qualification?
      CXXScopeSpec ScopeSpec;
      DeclFilterCCC<VarDecl> Validator{};
      if (DiagnoseEmptyLookup(CurScope, ScopeSpec, R, Validator))
        continue;
    }

    if (auto *BD = R.getAsSingle<BindingDecl>())
44
←
Assuming 'BD' is non-null→
45
←
Taking true branch→
      Var = BD;
    else
      Var = R.getAsSingle<VarDecl>();
    if (Var45.1
'Var' is non-null
 && DiagnoseUseOfDecl(Var, C->Loc))
46
←
Assuming the condition is false→
47
←
Taking false branch→
      continue;
  }

  // C++11 [expr.prim.lambda]p8:
  //   An identifier or this shall not appear more than once in a
  //   lambda-capture.
  if (!CaptureNames.insert(C->Id).second) {
48
←
Assuming field 'second' is true→
49
←
Taking false branch→
    if (Var && LSI->isCaptured(Var)) {
      Diag(C->Loc, diag::err_capture_more_than_once)
          << C->Id << SourceRange(LSI->getCapture(Var).getLocation())
          << FixItHint::CreateRemoval(
                 SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
    } else
      // Previous capture captured something different (one or both was
      // an init-cpature): no fixit.
      Diag(C->Loc, diag::err_capture_more_than_once) << C->Id;
    continue;
  }

  // C++11 [expr.prim.lambda]p10:
  //   [...] each such lookup shall find a variable with automatic storage
  //   duration declared in the reaching scope of the local lambda expression.
  // Note that the 'reaching scope' check happens in tryCaptureVariable().
  if (!Var49.1
'Var' is non-null
) {
50
←
Taking false branch→
    Diag(C->Loc, diag::err_capture_does_not_name_variable) << C->Id;
    continue;
  }

  // Ignore invalid decls; they'll just confuse the code later.
  if (Var->isInvalidDecl())
51
←
Assuming the condition is false→
52
←
Taking false branch→
    continue;

  VarDecl *Underlying;
  if (auto *BD53.1
'BD' is non-null
 = dyn_cast<BindingDecl>(Var))
53
←
Assuming 'Var' is a 'CastReturnType'→
54
←
Taking true branch→
    Underlying = dyn_cast<VarDecl>(BD->getDecomposedDecl());
55
←
Assuming the object is not a 'CastReturnType'→
56
←
Null pointer value stored to 'Underlying'→
  else
    Underlying = cast<VarDecl>(Var);

  if (!Underlying->hasLocalStorage()) {
57
←
Called C++ object pointer is null
    Diag(C->Loc, diag::err_capture_non_automatic_variable) << C->Id;
    Diag(Var->getLocation(), diag::note_previous_decl) << C->Id;
    continue;
  }

  // C++11 [expr.prim.lambda]p23:
  //   A capture followed by an ellipsis is a pack expansion (14.5.3).
  SourceLocation EllipsisLoc;
  if (C->EllipsisLoc.isValid()) {
    if (Var->isParameterPack()) {
      EllipsisLoc = C->EllipsisLoc;
    } else {
      Diag(C->EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
          << (C->Init.isUsable() ? C->Init.get()->getSourceRange()
                                 : SourceRange(C->Loc));

      // Just ignore the ellipsis.
    }
  } else if (Var->isParameterPack()) {
    ContainsUnexpandedParameterPack = true;
  }

  if (C->Init.isUsable()) {
    addInitCapture(LSI, cast<VarDecl>(Var), C->Kind == LCK_ByRef);
  } else {
    TryCaptureKind Kind = C->Kind == LCK_ByRef ? TryCapture_ExplicitByRef :
                                                 TryCapture_ExplicitByVal;
    tryCaptureVariable(Var, C->Loc, Kind, EllipsisLoc);
  }
  if (!LSI->Captures.empty())
    LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange;
}
finishLambdaExplicitCaptures(LSI);

LSI->ContainsUnexpandedParameterPack |= ContainsUnexpandedParameterPack;

// Add lambda parameters into scope.
addLambdaParameters(Intro.Captures, Method, CurScope);

// Enter a new evaluation context to insulate the lambda from any
// cleanups from the enclosing full-expression.
PushExpressionEvaluationContext(
    LSI->CallOperator->isConsteval()
        ? ExpressionEvaluationContext::ImmediateFunctionContext
        : ExpressionEvaluationContext::PotentiallyEvaluated);
1287}

1289void Sema::ActOnLambdaError(SourceLocation StartLoc, Scope *CurScope,
                          bool IsInstantiation) {
LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(FunctionScopes.back());

// Leave the expression-evaluation context.
DiscardCleanupsInEvaluationContext();
PopExpressionEvaluationContext();

// Leave the context of the lambda.
if (!IsInstantiation)
  PopDeclContext();

// Finalize the lambda.
CXXRecordDecl *Class = LSI->Lambda;
Class->setInvalidDecl();
SmallVector<Decl*, 4> Fields(Class->fields());
ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
            SourceLocation(), ParsedAttributesView());
CheckCompletedCXXClass(nullptr, Class);

PopFunctionScopeInfo();
1310}

1312template <typename Func>
1313static void repeatForLambdaConversionFunctionCallingConvs(
  Sema &S, const FunctionProtoType &CallOpProto, Func F) {
CallingConv DefaultFree = S.Context.getDefaultCallingConvention(
    CallOpProto.isVariadic(), /*IsCXXMethod=*/false);
CallingConv DefaultMember = S.Context.getDefaultCallingConvention(
    CallOpProto.isVariadic(), /*IsCXXMethod=*/true);
CallingConv CallOpCC = CallOpProto.getCallConv();

/// Implement emitting a version of the operator for many of the calling
/// conventions for MSVC, as described here:
/// https://devblogs.microsoft.com/oldnewthing/20150220-00/?p=44623.
/// Experimentally, we determined that cdecl, stdcall, fastcall, and
/// vectorcall are generated by MSVC when it is supported by the target.
/// Additionally, we are ensuring that the default-free/default-member and
/// call-operator calling convention are generated as well.
/// NOTE: We intentionally generate a 'thiscall' on Win32 implicitly from the
/// 'member default', despite MSVC not doing so. We do this in order to ensure
/// that someone who intentionally places 'thiscall' on the lambda call
/// operator will still get that overload, since we don't have the a way of
/// detecting the attribute by the time we get here.
if (S.getLangOpts().MSVCCompat) {
  CallingConv Convs[] = {
      CC_C,        CC_X86StdCall, CC_X86FastCall, CC_X86VectorCall,
      DefaultFree, DefaultMember, CallOpCC};
  llvm::sort(Convs);
  llvm::iterator_range<CallingConv *> Range(
      std::begin(Convs), std::unique(std::begin(Convs), std::end(Convs)));
  const TargetInfo &TI = S.getASTContext().getTargetInfo();

  for (CallingConv C : Range) {
    if (TI.checkCallingConvention(C) == TargetInfo::CCCR_OK)
      F(C);
  }
  return;
}

if (CallOpCC == DefaultMember && DefaultMember != DefaultFree) {
  F(DefaultFree);
  F(DefaultMember);
} else {
  F(CallOpCC);
}
1355}

1357// Returns the 'standard' calling convention to be used for the lambda
1358// conversion function, that is, the 'free' function calling convention unless
1359// it is overridden by a non-default calling convention attribute.
1360static CallingConv
1361getLambdaConversionFunctionCallConv(Sema &S,
                                  const FunctionProtoType *CallOpProto) {
CallingConv DefaultFree = S.Context.getDefaultCallingConvention(
    CallOpProto->isVariadic(), /*IsCXXMethod=*/false);
CallingConv DefaultMember = S.Context.getDefaultCallingConvention(
    CallOpProto->isVariadic(), /*IsCXXMethod=*/true);
CallingConv CallOpCC = CallOpProto->getCallConv();

// If the call-operator hasn't been changed, return both the 'free' and
// 'member' function calling convention.
if (CallOpCC == DefaultMember && DefaultMember != DefaultFree)
  return DefaultFree;
return CallOpCC;
1374}

1376QualType Sema::getLambdaConversionFunctionResultType(
  const FunctionProtoType *CallOpProto, CallingConv CC) {
const FunctionProtoType::ExtProtoInfo CallOpExtInfo =
    CallOpProto->getExtProtoInfo();
FunctionProtoType::ExtProtoInfo InvokerExtInfo = CallOpExtInfo;
InvokerExtInfo.ExtInfo = InvokerExtInfo.ExtInfo.withCallingConv(CC);
InvokerExtInfo.TypeQuals = Qualifiers();
assert(InvokerExtInfo.RefQualifier == RQ_None &&(static_cast <bool> (InvokerExtInfo.RefQualifier == RQ_None
 && "Lambda's call operator should not have a reference qualifier"
) ? void (0) : __assert_fail ("InvokerExtInfo.RefQualifier == RQ_None && \"Lambda's call operator should not have a reference qualifier\""
, "clang/lib/Sema/SemaLambda.cpp", 1384, __extension__ __PRETTY_FUNCTION__
))
       "Lambda's call operator should not have a reference qualifier")(static_cast <bool> (InvokerExtInfo.RefQualifier == RQ_None
 && "Lambda's call operator should not have a reference qualifier"
) ? void (0) : __assert_fail ("InvokerExtInfo.RefQualifier == RQ_None && \"Lambda's call operator should not have a reference qualifier\""
, "clang/lib/Sema/SemaLambda.cpp", 1384, __extension__ __PRETTY_FUNCTION__
));
return Context.getFunctionType(CallOpProto->getReturnType(),
                               CallOpProto->getParamTypes(), InvokerExtInfo);
1387}

1389/// Add a lambda's conversion to function pointer, as described in
1390/// C++11 [expr.prim.lambda]p6.
1391static void addFunctionPointerConversion(Sema &S, SourceRange IntroducerRange,
                                       CXXRecordDecl *Class,
                                       CXXMethodDecl *CallOperator,
                                       QualType InvokerFunctionTy) {
// This conversion is explicitly disabled if the lambda's function has
// pass_object_size attributes on any of its parameters.
auto HasPassObjectSizeAttr = [](const ParmVarDecl *P) {
  return P->hasAttr<PassObjectSizeAttr>();
};
if (llvm::any_of(CallOperator->parameters(), HasPassObjectSizeAttr))
  return;

// Add the conversion to function pointer.
QualType PtrToFunctionTy = S.Context.getPointerType(InvokerFunctionTy);

// Create the type of the conversion function.
FunctionProtoType::ExtProtoInfo ConvExtInfo(
    S.Context.getDefaultCallingConvention(
    /*IsVariadic=*/false, /*IsCXXMethod=*/true));
// The conversion function is always const and noexcept.
ConvExtInfo.TypeQuals = Qualifiers();
ConvExtInfo.TypeQuals.addConst();
ConvExtInfo.ExceptionSpec.Type = EST_BasicNoexcept;
QualType ConvTy =
    S.Context.getFunctionType(PtrToFunctionTy, std::nullopt, ConvExtInfo);

SourceLocation Loc = IntroducerRange.getBegin();
DeclarationName ConversionName
  = S.Context.DeclarationNames.getCXXConversionFunctionName(
      S.Context.getCanonicalType(PtrToFunctionTy));
// Construct a TypeSourceInfo for the conversion function, and wire
// all the parameters appropriately for the FunctionProtoTypeLoc
// so that everything works during transformation/instantiation of
// generic lambdas.
// The main reason for wiring up the parameters of the conversion
// function with that of the call operator is so that constructs
// like the following work:
// auto L = [](auto b) {                <-- 1
//   return [](auto a) -> decltype(a) { <-- 2
//      return a;
//   };
// };
// int (*fp)(int) = L(5);
// Because the trailing return type can contain DeclRefExprs that refer
// to the original call operator's variables, we hijack the call
// operators ParmVarDecls below.
TypeSourceInfo *ConvNamePtrToFunctionTSI =
    S.Context.getTrivialTypeSourceInfo(PtrToFunctionTy, Loc);
DeclarationNameLoc ConvNameLoc =
    DeclarationNameLoc::makeNamedTypeLoc(ConvNamePtrToFunctionTSI);

// The conversion function is a conversion to a pointer-to-function.
TypeSourceInfo *ConvTSI = S.Context.getTrivialTypeSourceInfo(ConvTy, Loc);
FunctionProtoTypeLoc ConvTL =
    ConvTSI->getTypeLoc().getAs<FunctionProtoTypeLoc>();
// Get the result of the conversion function which is a pointer-to-function.
PointerTypeLoc PtrToFunctionTL =
    ConvTL.getReturnLoc().getAs<PointerTypeLoc>();
// Do the same for the TypeSourceInfo that is used to name the conversion
// operator.
PointerTypeLoc ConvNamePtrToFunctionTL =
    ConvNamePtrToFunctionTSI->getTypeLoc().getAs<PointerTypeLoc>();

// Get the underlying function types that the conversion function will
// be converting to (should match the type of the call operator).
FunctionProtoTypeLoc CallOpConvTL =
    PtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();
FunctionProtoTypeLoc CallOpConvNameTL =
  ConvNamePtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();

// Wire up the FunctionProtoTypeLocs with the call operator's parameters.
// These parameter's are essentially used to transform the name and
// the type of the conversion operator.  By using the same parameters
// as the call operator's we don't have to fix any back references that
// the trailing return type of the call operator's uses (such as
// decltype(some_type<decltype(a)>::type{} + decltype(a){}) etc.)
// - we can simply use the return type of the call operator, and
// everything should work.
SmallVector<ParmVarDecl *, 4> InvokerParams;
for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I) {
  ParmVarDecl *From = CallOperator->getParamDecl(I);

  InvokerParams.push_back(ParmVarDecl::Create(
      S.Context,
      // Temporarily add to the TU. This is set to the invoker below.
      S.Context.getTranslationUnitDecl(), From->getBeginLoc(),
      From->getLocation(), From->getIdentifier(), From->getType(),
      From->getTypeSourceInfo(), From->getStorageClass(),
      /*DefArg=*/nullptr));
  CallOpConvTL.setParam(I, From);
  CallOpConvNameTL.setParam(I, From);
}

CXXConversionDecl *Conversion = CXXConversionDecl::Create(
    S.Context, Class, Loc,
    DeclarationNameInfo(ConversionName, Loc, ConvNameLoc), ConvTy, ConvTSI,
    S.getCurFPFeatures().isFPConstrained(),
    /*isInline=*/true, ExplicitSpecifier(),
    S.getLangOpts().CPlusPlus17 ? ConstexprSpecKind::Constexpr
                                : ConstexprSpecKind::Unspecified,
    CallOperator->getBody()->getEndLoc());
Conversion->setAccess(AS_public);
Conversion->setImplicit(true);

if (Class->isGenericLambda()) {
  // Create a template version of the conversion operator, using the template
  // parameter list of the function call operator.
  FunctionTemplateDecl *TemplateCallOperator =
          CallOperator->getDescribedFunctionTemplate();
  FunctionTemplateDecl *ConversionTemplate =
                FunctionTemplateDecl::Create(S.Context, Class,
                                    Loc, ConversionName,
                                    TemplateCallOperator->getTemplateParameters(),
                                    Conversion);
  ConversionTemplate->setAccess(AS_public);
  ConversionTemplate->setImplicit(true);
  Conversion->setDescribedFunctionTemplate(ConversionTemplate);
  Class->addDecl(ConversionTemplate);
} else
  Class->addDecl(Conversion);

// If the lambda is not static, we need to add a static member
// function that will be the result of the conversion with a
// certain unique ID.
// When it is static we just return the static call operator instead.
if (CallOperator->isInstance()) {
  DeclarationName InvokerName =
      &S.Context.Idents.get(getLambdaStaticInvokerName());
  // FIXME: Instead of passing in the CallOperator->getTypeSourceInfo()
  // we should get a prebuilt TrivialTypeSourceInfo from Context
  // using FunctionTy & Loc and get its TypeLoc as a FunctionProtoTypeLoc
  // then rewire the parameters accordingly, by hoisting up the InvokeParams
  // loop below and then use its Params to set Invoke->setParams(...) below.
  // This would avoid the 'const' qualifier of the calloperator from
  // contaminating the type of the invoker, which is currently adjusted
  // in SemaTemplateDeduction.cpp:DeduceTemplateArguments.  Fixing the
  // trailing return type of the invoker would require a visitor to rebuild
  // the trailing return type and adjusting all back DeclRefExpr's to refer
  // to the new static invoker parameters - not the call operator's.
  CXXMethodDecl *Invoke = CXXMethodDecl::Create(
      S.Context, Class, Loc, DeclarationNameInfo(InvokerName, Loc),
      InvokerFunctionTy, CallOperator->getTypeSourceInfo(), SC_Static,
      S.getCurFPFeatures().isFPConstrained(),
      /*isInline=*/true, ConstexprSpecKind::Unspecified,
      CallOperator->getBody()->getEndLoc());
  for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I)
    InvokerParams[I]->setOwningFunction(Invoke);
  Invoke->setParams(InvokerParams);
  Invoke->setAccess(AS_private);
  Invoke->setImplicit(true);
  if (Class->isGenericLambda()) {
    FunctionTemplateDecl *TemplateCallOperator =
        CallOperator->getDescribedFunctionTemplate();
    FunctionTemplateDecl *StaticInvokerTemplate =
        FunctionTemplateDecl::Create(
            S.Context, Class, Loc, InvokerName,
            TemplateCallOperator->getTemplateParameters(), Invoke);
    StaticInvokerTemplate->setAccess(AS_private);
    StaticInvokerTemplate->setImplicit(true);
    Invoke->setDescribedFunctionTemplate(StaticInvokerTemplate);
    Class->addDecl(StaticInvokerTemplate);
  } else
    Class->addDecl(Invoke);
}
1555}

1557/// Add a lambda's conversion to function pointers, as described in
1558/// C++11 [expr.prim.lambda]p6. Note that in most cases, this should emit only a
1559/// single pointer conversion. In the event that the default calling convention
1560/// for free and member functions is different, it will emit both conventions.
1561static void addFunctionPointerConversions(Sema &S, SourceRange IntroducerRange,
                                        CXXRecordDecl *Class,
                                        CXXMethodDecl *CallOperator) {
const FunctionProtoType *CallOpProto =
    CallOperator->getType()->castAs<FunctionProtoType>();

repeatForLambdaConversionFunctionCallingConvs(
    S, *CallOpProto, [&](CallingConv CC) {
      QualType InvokerFunctionTy =
          S.getLambdaConversionFunctionResultType(CallOpProto, CC);
      addFunctionPointerConversion(S, IntroducerRange, Class, CallOperator,
                                   InvokerFunctionTy);
    });
1574}

1576/// Add a lambda's conversion to block pointer.
1577static void addBlockPointerConversion(Sema &S,
                                    SourceRange IntroducerRange,
                                    CXXRecordDecl *Class,
                                    CXXMethodDecl *CallOperator) {
const FunctionProtoType *CallOpProto =
    CallOperator->getType()->castAs<FunctionProtoType>();
QualType FunctionTy = S.getLambdaConversionFunctionResultType(
    CallOpProto, getLambdaConversionFunctionCallConv(S, CallOpProto));
QualType BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);

FunctionProtoType::ExtProtoInfo ConversionEPI(
    S.Context.getDefaultCallingConvention(
        /*IsVariadic=*/false, /*IsCXXMethod=*/true));
ConversionEPI.TypeQuals = Qualifiers();
ConversionEPI.TypeQuals.addConst();
QualType ConvTy =
    S.Context.getFunctionType(BlockPtrTy, std::nullopt, ConversionEPI);

SourceLocation Loc = IntroducerRange.getBegin();
DeclarationName Name
  = S.Context.DeclarationNames.getCXXConversionFunctionName(
      S.Context.getCanonicalType(BlockPtrTy));
DeclarationNameLoc NameLoc = DeclarationNameLoc::makeNamedTypeLoc(
    S.Context.getTrivialTypeSourceInfo(BlockPtrTy, Loc));
CXXConversionDecl *Conversion = CXXConversionDecl::Create(
    S.Context, Class, Loc, DeclarationNameInfo(Name, Loc, NameLoc), ConvTy,
    S.Context.getTrivialTypeSourceInfo(ConvTy, Loc),
    S.getCurFPFeatures().isFPConstrained(),
    /*isInline=*/true, ExplicitSpecifier(), ConstexprSpecKind::Unspecified,
    CallOperator->getBody()->getEndLoc());
Conversion->setAccess(AS_public);
Conversion->setImplicit(true);
Class->addDecl(Conversion);
1610}

1612ExprResult Sema::BuildCaptureInit(const Capture &Cap,
                                SourceLocation ImplicitCaptureLoc,
                                bool IsOpenMPMapping) {
// VLA captures don't have a stored initialization expression.
if (Cap.isVLATypeCapture())
  return ExprResult();

// An init-capture is initialized directly from its stored initializer.
if (Cap.isInitCapture())
  return cast<VarDecl>(Cap.getVariable())->getInit();

// For anything else, build an initialization expression. For an implicit
// capture, the capture notionally happens at the capture-default, so use
// that location here.
SourceLocation Loc =
    ImplicitCaptureLoc.isValid() ? ImplicitCaptureLoc : Cap.getLocation();

// C++11 [expr.prim.lambda]p21:
//   When the lambda-expression is evaluated, the entities that
//   are captured by copy are used to direct-initialize each
//   corresponding non-static data member of the resulting closure
//   object. (For array members, the array elements are
//   direct-initialized in increasing subscript order.) These
//   initializations are performed in the (unspecified) order in
//   which the non-static data members are declared.

// C++ [expr.prim.lambda]p12:
//   An entity captured by a lambda-expression is odr-used (3.2) in
//   the scope containing the lambda-expression.
ExprResult Init;
IdentifierInfo *Name = nullptr;
if (Cap.isThisCapture()) {
  QualType ThisTy = getCurrentThisType();
  Expr *This = BuildCXXThisExpr(Loc, ThisTy, ImplicitCaptureLoc.isValid());
  if (Cap.isCopyCapture())
    Init = CreateBuiltinUnaryOp(Loc, UO_Deref, This);
  else
    Init = This;
} else {
  assert(Cap.isVariableCapture() && "unknown kind of capture")(static_cast <bool> (Cap.isVariableCapture() &&
 "unknown kind of capture") ? void (0) : __assert_fail ("Cap.isVariableCapture() && \"unknown kind of capture\""
, "clang/lib/Sema/SemaLambda.cpp", 1651, __extension__ __PRETTY_FUNCTION__
));
  ValueDecl *Var = Cap.getVariable();
  Name = Var->getIdentifier();
  Init = BuildDeclarationNameExpr(
    CXXScopeSpec(), DeclarationNameInfo(Var->getDeclName(), Loc), Var);
}

// In OpenMP, the capture kind doesn't actually describe how to capture:
// variables are "mapped" onto the device in a process that does not formally
// make a copy, even for a "copy capture".
if (IsOpenMPMapping)
  return Init;

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

Expr *InitExpr = Init.get();
InitializedEntity Entity = InitializedEntity::InitializeLambdaCapture(
    Name, Cap.getCaptureType(), Loc);
InitializationKind InitKind =
    InitializationKind::CreateDirect(Loc, Loc, Loc);
InitializationSequence InitSeq(*this, Entity, InitKind, InitExpr);
return InitSeq.Perform(*this, Entity, InitKind, InitExpr);
1674}

1676ExprResult Sema::ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
                               Scope *CurScope) {
LambdaScopeInfo LSI = *cast<LambdaScopeInfo>(FunctionScopes.back());
ActOnFinishFunctionBody(LSI.CallOperator, Body);
return BuildLambdaExpr(StartLoc, Body->getEndLoc(), &LSI);
1681}

1683static LambdaCaptureDefault
1684mapImplicitCaptureStyle(CapturingScopeInfo::ImplicitCaptureStyle ICS) {
switch (ICS) {
case CapturingScopeInfo::ImpCap_None:
  return LCD_None;
case CapturingScopeInfo::ImpCap_LambdaByval:
  return LCD_ByCopy;
case CapturingScopeInfo::ImpCap_CapturedRegion:
case CapturingScopeInfo::ImpCap_LambdaByref:
  return LCD_ByRef;
case CapturingScopeInfo::ImpCap_Block:
  llvm_unreachable("block capture in lambda")::llvm::llvm_unreachable_internal("block capture in lambda", "clang/lib/Sema/SemaLambda.cpp"
, 1694);
}
llvm_unreachable("Unknown implicit capture style")::llvm::llvm_unreachable_internal("Unknown implicit capture style"
, "clang/lib/Sema/SemaLambda.cpp", 1696);
1697}

1699bool Sema::CaptureHasSideEffects(const Capture &From) {
if (From.isInitCapture()) {
  Expr *Init = cast<VarDecl>(From.getVariable())->getInit();
  if (Init && Init->HasSideEffects(Context))
    return true;
}

if (!From.isCopyCapture())
  return false;

const QualType T = From.isThisCapture()
                       ? getCurrentThisType()->getPointeeType()
                       : From.getCaptureType();

if (T.isVolatileQualified())
  return true;

const Type *BaseT = T->getBaseElementTypeUnsafe();
if (const CXXRecordDecl *RD = BaseT->getAsCXXRecordDecl())
  return !RD->isCompleteDefinition() || !RD->hasTrivialCopyConstructor() ||
         !RD->hasTrivialDestructor();

return false;
1722}

1724bool Sema::DiagnoseUnusedLambdaCapture(SourceRange CaptureRange,
                                     const Capture &From) {
if (CaptureHasSideEffects(From))
  return false;

if (From.isVLATypeCapture())
  return false;

auto diag = Diag(From.getLocation(), diag::warn_unused_lambda_capture);
if (From.isThisCapture())
  diag << "'this'";
else
  diag << From.getVariable();
diag << From.isNonODRUsed();
diag << FixItHint::CreateRemoval(CaptureRange);
return true;
1740}

1742/// Create a field within the lambda class or captured statement record for the
1743/// given capture.
1744FieldDecl *Sema::BuildCaptureField(RecordDecl *RD,
                                 const sema::Capture &Capture) {
SourceLocation Loc = Capture.getLocation();
QualType FieldType = Capture.getCaptureType();

TypeSourceInfo *TSI = nullptr;
if (Capture.isVariableCapture()) {
  const auto *Var = dyn_cast_or_null<VarDecl>(Capture.getVariable());
  if (Var && Var->isInitCapture())
    TSI = Var->getTypeSourceInfo();
}

// FIXME: Should we really be doing this? A null TypeSourceInfo seems more
// appropriate, at least for an implicit capture.
if (!TSI)
  TSI = Context.getTrivialTypeSourceInfo(FieldType, Loc);

// Build the non-static data member.
FieldDecl *Field =
    FieldDecl::Create(Context, RD, /*StartLoc=*/Loc, /*IdLoc=*/Loc,
                      /*Id=*/nullptr, FieldType, TSI, /*BW=*/nullptr,
                      /*Mutable=*/false, ICIS_NoInit);
// If the variable being captured has an invalid type, mark the class as
// invalid as well.
if (!FieldType->isDependentType()) {
  if (RequireCompleteSizedType(Loc, FieldType,
                               diag::err_field_incomplete_or_sizeless)) {
    RD->setInvalidDecl();
    Field->setInvalidDecl();
  } else {
    NamedDecl *Def;
    FieldType->isIncompleteType(&Def);
    if (Def && Def->isInvalidDecl()) {
      RD->setInvalidDecl();
      Field->setInvalidDecl();
    }
  }
}
Field->setImplicit(true);
Field->setAccess(AS_private);
RD->addDecl(Field);

if (Capture.isVLATypeCapture())
  Field->setCapturedVLAType(Capture.getCapturedVLAType());

return Field;
1790}

1792ExprResult Sema::BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
                               LambdaScopeInfo *LSI) {
// Collect information from the lambda scope.
SmallVector<LambdaCapture, 4> Captures;
SmallVector<Expr *, 4> CaptureInits;
SourceLocation CaptureDefaultLoc = LSI->CaptureDefaultLoc;
LambdaCaptureDefault CaptureDefault =
    mapImplicitCaptureStyle(LSI->ImpCaptureStyle);
CXXRecordDecl *Class;
CXXMethodDecl *CallOperator;
SourceRange IntroducerRange;
bool ExplicitParams;
bool ExplicitResultType;
CleanupInfo LambdaCleanup;
bool ContainsUnexpandedParameterPack;
bool IsGenericLambda;
{
  CallOperator = LSI->CallOperator;
  Class = LSI->Lambda;
  IntroducerRange = LSI->IntroducerRange;
  ExplicitParams = LSI->ExplicitParams;
  ExplicitResultType = !LSI->HasImplicitReturnType;
  LambdaCleanup = LSI->Cleanup;
  ContainsUnexpandedParameterPack = LSI->ContainsUnexpandedParameterPack;
  IsGenericLambda = Class->isGenericLambda();

  CallOperator->setLexicalDeclContext(Class);
  Decl *TemplateOrNonTemplateCallOperatorDecl =
      CallOperator->getDescribedFunctionTemplate()
      ? CallOperator->getDescribedFunctionTemplate()
      : cast<Decl>(CallOperator);

  // FIXME: Is this really the best choice? Keeping the lexical decl context
  // set as CurContext seems more faithful to the source.
  TemplateOrNonTemplateCallOperatorDecl->setLexicalDeclContext(Class);

  PopExpressionEvaluationContext();

  // True if the current capture has a used capture or default before it.
  bool CurHasPreviousCapture = CaptureDefault != LCD_None;
  SourceLocation PrevCaptureLoc = CurHasPreviousCapture ?
      CaptureDefaultLoc : IntroducerRange.getBegin();

  for (unsigned I = 0, N = LSI->Captures.size(); I != N; ++I) {
    const Capture &From = LSI->Captures[I];

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

    assert(!From.isBlockCapture() && "Cannot capture __block variables")(static_cast <bool> (!From.isBlockCapture() && "Cannot capture __block variables"
) ? void (0) : __assert_fail ("!From.isBlockCapture() && \"Cannot capture __block variables\""
, "clang/lib/Sema/SemaLambda.cpp", 1841, __extension__ __PRETTY_FUNCTION__
));
    bool IsImplicit = I >= LSI->NumExplicitCaptures;
    SourceLocation ImplicitCaptureLoc =
        IsImplicit ? CaptureDefaultLoc : SourceLocation();

    // Use source ranges of explicit captures for fixits where available.
    SourceRange CaptureRange = LSI->ExplicitCaptureRanges[I];

    // Warn about unused explicit captures.
    bool IsCaptureUsed = true;
    if (!CurContext->isDependentContext() && !IsImplicit &&
        !From.isODRUsed()) {
      // Initialized captures that are non-ODR used may not be eliminated.
      // FIXME: Where did the IsGenericLambda here come from?
      bool NonODRUsedInitCapture =
          IsGenericLambda && From.isNonODRUsed() && From.isInitCapture();
      if (!NonODRUsedInitCapture) {
        bool IsLast = (I + 1) == LSI->NumExplicitCaptures;
        SourceRange FixItRange;
        if (CaptureRange.isValid()) {
          if (!CurHasPreviousCapture && !IsLast) {
            // If there are no captures preceding this capture, remove the
            // following comma.
            FixItRange = SourceRange(CaptureRange.getBegin(),
                                     getLocForEndOfToken(CaptureRange.getEnd()));
          } else {
            // Otherwise, remove the comma since the last used capture.
            FixItRange = SourceRange(getLocForEndOfToken(PrevCaptureLoc),
                                     CaptureRange.getEnd());
          }
        }

        IsCaptureUsed = !DiagnoseUnusedLambdaCapture(FixItRange, From);
      }
    }

    if (CaptureRange.isValid()) {
      CurHasPreviousCapture |= IsCaptureUsed;
      PrevCaptureLoc = CaptureRange.getEnd();
    }

    // Map the capture to our AST representation.
    LambdaCapture Capture = [&] {
      if (From.isThisCapture()) {
        // Capturing 'this' implicitly with a default of '[=]' is deprecated,
        // because it results in a reference capture. Don't warn prior to
        // C++2a; there's nothing that can be done about it before then.
        if (getLangOpts().CPlusPlus20 && IsImplicit &&
            CaptureDefault == LCD_ByCopy) {
          Diag(From.getLocation(), diag::warn_deprecated_this_capture);
          Diag(CaptureDefaultLoc, diag::note_deprecated_this_capture)
              << FixItHint::CreateInsertion(
                     getLocForEndOfToken(CaptureDefaultLoc), ", this");
        }
        return LambdaCapture(From.getLocation(), IsImplicit,
                             From.isCopyCapture() ? LCK_StarThis : LCK_This);
      } else if (From.isVLATypeCapture()) {
        return LambdaCapture(From.getLocation(), IsImplicit, LCK_VLAType);
      } else {
        assert(From.isVariableCapture() && "unknown kind of capture")(static_cast <bool> (From.isVariableCapture() &&
 "unknown kind of capture") ? void (0) : __assert_fail ("From.isVariableCapture() && \"unknown kind of capture\""
, "clang/lib/Sema/SemaLambda.cpp", 1900, __extension__ __PRETTY_FUNCTION__
));
        ValueDecl *Var = From.getVariable();
        LambdaCaptureKind Kind =
            From.isCopyCapture() ? LCK_ByCopy : LCK_ByRef;
        return LambdaCapture(From.getLocation(), IsImplicit, Kind, Var,
                             From.getEllipsisLoc());
      }
    }();

    // Form the initializer for the capture field.
    ExprResult Init = BuildCaptureInit(From, ImplicitCaptureLoc);

    // FIXME: Skip this capture if the capture is not used, the initializer
    // has no side-effects, the type of the capture is trivial, and the
    // lambda is not externally visible.

    // Add a FieldDecl for the capture and form its initializer.
    BuildCaptureField(Class, From);
    Captures.push_back(Capture);
    CaptureInits.push_back(Init.get());

    if (LangOpts.CUDA)
      CUDACheckLambdaCapture(CallOperator, From);
  }

  Class->setCaptures(Context, Captures);

  // C++11 [expr.prim.lambda]p6:
  //   The closure type for a lambda-expression with no lambda-capture
  //   has a public non-virtual non-explicit const conversion function
  //   to pointer to function having the same parameter and return
  //   types as the closure type's function call operator.
  if (Captures.empty() && CaptureDefault == LCD_None)
    addFunctionPointerConversions(*this, IntroducerRange, Class,
                                  CallOperator);

  // Objective-C++:
  //   The closure type for a lambda-expression has a public non-virtual
  //   non-explicit const conversion function to a block pointer having the
  //   same parameter and return types as the closure type's function call
  //   operator.
  // FIXME: Fix generic lambda to block conversions.
  if (getLangOpts().Blocks && getLangOpts().ObjC && !IsGenericLambda)
    addBlockPointerConversion(*this, IntroducerRange, Class, CallOperator);

  // Finalize the lambda class.
  SmallVector<Decl*, 4> Fields(Class->fields());
  ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
              SourceLocation(), ParsedAttributesView());
  CheckCompletedCXXClass(nullptr, Class);
}

Cleanup.mergeFrom(LambdaCleanup);

LambdaExpr *Lambda = LambdaExpr::Create(Context, Class, IntroducerRange,
                                        CaptureDefault, CaptureDefaultLoc,
                                        ExplicitParams, ExplicitResultType,
                                        CaptureInits, EndLoc,
                                        ContainsUnexpandedParameterPack);
// If the lambda expression's call operator is not explicitly marked constexpr
// and we are not in a dependent context, analyze the call operator to infer
// its constexpr-ness, suppressing diagnostics while doing so.
if (getLangOpts().CPlusPlus17 && !CallOperator->isInvalidDecl() &&
    !CallOperator->isConstexpr() &&
    !isa<CoroutineBodyStmt>(CallOperator->getBody()) &&
    !Class->getDeclContext()->isDependentContext()) {
  CallOperator->setConstexprKind(
      CheckConstexprFunctionDefinition(CallOperator,
                                       CheckConstexprKind::CheckValid)
          ? ConstexprSpecKind::Constexpr
          : ConstexprSpecKind::Unspecified);
}

// Emit delayed shadowing warnings now that the full capture list is known.
DiagnoseShadowingLambdaDecls(LSI);

if (!CurContext->isDependentContext()) {
  switch (ExprEvalContexts.back().Context) {
  // C++11 [expr.prim.lambda]p2:
  //   A lambda-expression shall not appear in an unevaluated operand
  //   (Clause 5).
  case ExpressionEvaluationContext::Unevaluated:
  case ExpressionEvaluationContext::UnevaluatedList:
  case ExpressionEvaluationContext::UnevaluatedAbstract:
  // C++1y [expr.const]p2:
  //   A conditional-expression e is a core constant expression unless the
  //   evaluation of e, following the rules of the abstract machine, would
  //   evaluate [...] a lambda-expression.
  //
  // This is technically incorrect, there are some constant evaluated contexts
  // where this should be allowed.  We should probably fix this when DR1607 is
  // ratified, it lays out the exact set of conditions where we shouldn't
  // allow a lambda-expression.
  case ExpressionEvaluationContext::ConstantEvaluated:
  case ExpressionEvaluationContext::ImmediateFunctionContext:
    // We don't actually diagnose this case immediately, because we
    // could be within a context where we might find out later that
    // the expression is potentially evaluated (e.g., for typeid).
    ExprEvalContexts.back().Lambdas.push_back(Lambda);
    break;

  case ExpressionEvaluationContext::DiscardedStatement:
  case ExpressionEvaluationContext::PotentiallyEvaluated:
  case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
    break;
  }
}

return MaybeBindToTemporary(Lambda);
2009}

2011ExprResult Sema::BuildBlockForLambdaConversion(SourceLocation CurrentLocation,
                                             SourceLocation ConvLocation,
                                             CXXConversionDecl *Conv,
                                             Expr *Src) {
// Make sure that the lambda call operator is marked used.
CXXRecordDecl *Lambda = Conv->getParent();
CXXMethodDecl *CallOperator
  = cast<CXXMethodDecl>(
      Lambda->lookup(
        Context.DeclarationNames.getCXXOperatorName(OO_Call)).front());
CallOperator->setReferenced();
CallOperator->markUsed(Context);

ExprResult Init = PerformCopyInitialization(
    InitializedEntity::InitializeLambdaToBlock(ConvLocation, Src->getType()),
    CurrentLocation, Src);
if (!Init.isInvalid())
  Init = ActOnFinishFullExpr(Init.get(), /*DiscardedValue*/ false);

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

// Create the new block to be returned.
BlockDecl *Block = BlockDecl::Create(Context, CurContext, ConvLocation);

// Set the type information.
Block->setSignatureAsWritten(CallOperator->getTypeSourceInfo());
Block->setIsVariadic(CallOperator->isVariadic());
Block->setBlockMissingReturnType(false);

// Add parameters.
SmallVector<ParmVarDecl *, 4> BlockParams;
for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I) {
  ParmVarDecl *From = CallOperator->getParamDecl(I);
  BlockParams.push_back(ParmVarDecl::Create(
      Context, Block, From->getBeginLoc(), From->getLocation(),
      From->getIdentifier(), From->getType(), From->getTypeSourceInfo(),
      From->getStorageClass(),
      /*DefArg=*/nullptr));
}
Block->setParams(BlockParams);

Block->setIsConversionFromLambda(true);

// Add capture. The capture uses a fake variable, which doesn't correspond
// to any actual memory location. However, the initializer copy-initializes
// the lambda object.
TypeSourceInfo *CapVarTSI =
    Context.getTrivialTypeSourceInfo(Src->getType());
VarDecl *CapVar = VarDecl::Create(Context, Block, ConvLocation,
                                  ConvLocation, nullptr,
                                  Src->getType(), CapVarTSI,
                                  SC_None);
BlockDecl::Capture Capture(/*variable=*/CapVar, /*byRef=*/false,
                           /*nested=*/false, /*copy=*/Init.get());
Block->setCaptures(Context, Capture, /*CapturesCXXThis=*/false);

// Add a fake function body to the block. IR generation is responsible
// for filling in the actual body, which cannot be expressed as an AST.
Block->setBody(new (Context) CompoundStmt(ConvLocation));

// Create the block literal expression.
Expr *BuildBlock = new (Context) BlockExpr(Block, Conv->getConversionType());
ExprCleanupObjects.push_back(Block);
Cleanup.setExprNeedsCleanups(true);

return BuildBlock;
2078}