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SemaLambda.cpp
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1 //===--- SemaLambda.cpp - Semantic Analysis for C++11 Lambdas -------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements semantic analysis for C++ lambda expressions.
11 //
12 //===----------------------------------------------------------------------===//
13 #include "clang/Sema/DeclSpec.h"
14 #include "TypeLocBuilder.h"
15 #include "clang/AST/ASTLambda.h"
16 #include "clang/AST/ExprCXX.h"
17 #include "clang/Basic/TargetInfo.h"
19 #include "clang/Sema/Lookup.h"
20 #include "clang/Sema/Scope.h"
21 #include "clang/Sema/ScopeInfo.h"
23 #include "clang/Sema/SemaLambda.h"
24 using namespace clang;
25 using namespace sema;
26 
27 /// \brief 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.
61 
62 static inline Optional<unsigned>
65  VarDecl *VarToCapture) {
66  // Label failure to capture.
67  const Optional<unsigned> NoLambdaIsCaptureReady;
68 
69  // Ignore all inner captured regions.
70  unsigned CurScopeIndex = FunctionScopes.size() - 1;
71  while (CurScopeIndex > 0 && isa<clang::sema::CapturedRegionScopeInfo>(
72  FunctionScopes[CurScopeIndex]))
73  --CurScopeIndex;
74  assert(
75  isa<clang::sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]) &&
76  "The function on the top of sema's function-info stack must be a lambda");
77 
78  // If VarToCapture is null, we are attempting to capture 'this'.
79  const bool IsCapturingThis = !VarToCapture;
80  const bool IsCapturingVariable = !IsCapturingThis;
81 
82  // Start with the current lambda at the top of the stack (highest index).
83  DeclContext *EnclosingDC =
84  cast<sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex])->CallOperator;
85 
86  do {
87  const clang::sema::LambdaScopeInfo *LSI =
88  cast<sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]);
89  // IF we have climbed down to an intervening enclosing lambda that contains
90  // the variable declaration - it obviously can/must not capture the
91  // variable.
92  // Since its enclosing DC is dependent, all the lambdas between it and the
93  // innermost nested lambda are dependent (otherwise we wouldn't have
94  // arrived here) - so we don't yet have a lambda that can capture the
95  // variable.
96  if (IsCapturingVariable &&
97  VarToCapture->getDeclContext()->Equals(EnclosingDC))
98  return NoLambdaIsCaptureReady;
99 
100  // For an enclosing lambda to be capture ready for an entity, all
101  // intervening lambda's have to be able to capture that entity. If even
102  // one of the intervening lambda's is not capable of capturing the entity
103  // then no enclosing lambda can ever capture that entity.
104  // For e.g.
105  // const int x = 10;
106  // [=](auto a) { #1
107  // [](auto b) { #2 <-- an intervening lambda that can never capture 'x'
108  // [=](auto c) { #3
109  // f(x, c); <-- can not lead to x's speculative capture by #1 or #2
110  // }; }; };
111  // If they do not have a default implicit capture, check to see
112  // if the entity has already been explicitly captured.
113  // If even a single dependent enclosing lambda lacks the capability
114  // to ever capture this variable, there is no further enclosing
115  // non-dependent lambda that can capture this variable.
117  if (IsCapturingVariable && !LSI->isCaptured(VarToCapture))
118  return NoLambdaIsCaptureReady;
119  if (IsCapturingThis && !LSI->isCXXThisCaptured())
120  return NoLambdaIsCaptureReady;
121  }
122  EnclosingDC = getLambdaAwareParentOfDeclContext(EnclosingDC);
123 
124  assert(CurScopeIndex);
125  --CurScopeIndex;
126  } while (!EnclosingDC->isTranslationUnit() &&
127  EnclosingDC->isDependentContext() &&
128  isLambdaCallOperator(EnclosingDC));
129 
130  assert(CurScopeIndex < (FunctionScopes.size() - 1));
131  // If the enclosingDC is not dependent, then the immediately nested lambda
132  // (one index above) is capture-ready.
133  if (!EnclosingDC->isDependentContext())
134  return CurScopeIndex + 1;
135  return NoLambdaIsCaptureReady;
136 }
137 
138 /// \brief 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.
172 
175  VarDecl *VarToCapture, Sema &S) {
176 
177  const Optional<unsigned> NoLambdaIsCaptureCapable;
178 
179  const Optional<unsigned> OptionalStackIndex =
181  VarToCapture);
182  if (!OptionalStackIndex)
183  return NoLambdaIsCaptureCapable;
184 
185  const unsigned IndexOfCaptureReadyLambda = OptionalStackIndex.getValue();
186  assert(((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) ||
187  S.getCurGenericLambda()) &&
188  "The capture ready lambda for a potential capture can only be the "
189  "current lambda if it is a generic lambda");
190 
191  const sema::LambdaScopeInfo *const CaptureReadyLambdaLSI =
192  cast<sema::LambdaScopeInfo>(FunctionScopes[IndexOfCaptureReadyLambda]);
193 
194  // If VarToCapture is null, we are attempting to capture 'this'
195  const bool IsCapturingThis = !VarToCapture;
196  const bool IsCapturingVariable = !IsCapturingThis;
197 
198  if (IsCapturingVariable) {
199  // Check if the capture-ready lambda can truly capture the variable, by
200  // checking whether all enclosing lambdas of the capture-ready lambda allow
201  // the capture - i.e. make sure it is capture-capable.
202  QualType CaptureType, DeclRefType;
203  const bool CanCaptureVariable =
204  !S.tryCaptureVariable(VarToCapture,
205  /*ExprVarIsUsedInLoc*/ SourceLocation(),
207  /*EllipsisLoc*/ SourceLocation(),
208  /*BuildAndDiagnose*/ false, CaptureType,
209  DeclRefType, &IndexOfCaptureReadyLambda);
210  if (!CanCaptureVariable)
211  return NoLambdaIsCaptureCapable;
212  } else {
213  // Check if the capture-ready lambda can truly capture 'this' by checking
214  // whether all enclosing lambdas of the capture-ready lambda can capture
215  // 'this'.
216  const bool CanCaptureThis =
218  CaptureReadyLambdaLSI->PotentialThisCaptureLocation,
219  /*Explicit*/ false, /*BuildAndDiagnose*/ false,
220  &IndexOfCaptureReadyLambda);
221  if (!CanCaptureThis)
222  return NoLambdaIsCaptureCapable;
223  }
224  return IndexOfCaptureReadyLambda;
225 }
226 
227 static inline TemplateParameterList *
229  if (LSI->GLTemplateParameterList)
230  return LSI->GLTemplateParameterList;
231 
232  if (!LSI->AutoTemplateParams.empty()) {
233  SourceRange IntroRange = LSI->IntroducerRange;
234  SourceLocation LAngleLoc = IntroRange.getBegin();
235  SourceLocation RAngleLoc = IntroRange.getEnd();
237  SemaRef.Context,
238  /*Template kw loc*/ SourceLocation(), LAngleLoc,
239  llvm::makeArrayRef((NamedDecl *const *)LSI->AutoTemplateParams.data(),
240  LSI->AutoTemplateParams.size()),
241  RAngleLoc, nullptr);
242  }
243  return LSI->GLTemplateParameterList;
244 }
245 
247  TypeSourceInfo *Info,
248  bool KnownDependent,
249  LambdaCaptureDefault CaptureDefault) {
250  DeclContext *DC = CurContext;
251  while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext()))
252  DC = DC->getParent();
253  bool IsGenericLambda = getGenericLambdaTemplateParameterList(getCurLambda(),
254  *this);
255  // Start constructing the lambda class.
256  CXXRecordDecl *Class = CXXRecordDecl::CreateLambda(Context, DC, Info,
257  IntroducerRange.getBegin(),
258  KnownDependent,
259  IsGenericLambda,
260  CaptureDefault);
261  DC->addDecl(Class);
262 
263  return Class;
264 }
265 
266 /// \brief Determine whether the given context is or is enclosed in an inline
267 /// function.
268 static bool isInInlineFunction(const DeclContext *DC) {
269  while (!DC->isFileContext()) {
270  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(DC))
271  if (FD->isInlined())
272  return true;
273 
274  DC = DC->getLexicalParent();
275  }
276 
277  return false;
278 }
279 
282  Decl *&ManglingContextDecl) {
283  // Compute the context for allocating mangling numbers in the current
284  // expression, if the ABI requires them.
285  ManglingContextDecl = ExprEvalContexts.back().ManglingContextDecl;
286 
287  enum ContextKind {
288  Normal,
289  DefaultArgument,
290  DataMember,
291  StaticDataMember,
292  InlineVariable,
293  VariableTemplate
294  } Kind = Normal;
295 
296  // Default arguments of member function parameters that appear in a class
297  // definition, as well as the initializers of data members, receive special
298  // treatment. Identify them.
299  if (ManglingContextDecl) {
300  if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(ManglingContextDecl)) {
301  if (const DeclContext *LexicalDC
302  = Param->getDeclContext()->getLexicalParent())
303  if (LexicalDC->isRecord())
304  Kind = DefaultArgument;
305  } else if (VarDecl *Var = dyn_cast<VarDecl>(ManglingContextDecl)) {
306  if (Var->getDeclContext()->isRecord())
307  Kind = StaticDataMember;
308  else if (Var->getMostRecentDecl()->isInline())
309  Kind = InlineVariable;
310  else if (Var->getDescribedVarTemplate())
311  Kind = VariableTemplate;
312  else if (auto *VTS = dyn_cast<VarTemplateSpecializationDecl>(Var)) {
313  if (!VTS->isExplicitSpecialization())
314  Kind = VariableTemplate;
315  }
316  } else if (isa<FieldDecl>(ManglingContextDecl)) {
317  Kind = DataMember;
318  }
319  }
320 
321  // Itanium ABI [5.1.7]:
322  // In the following contexts [...] the one-definition rule requires closure
323  // types in different translation units to "correspond":
324  bool IsInNonspecializedTemplate =
325  inTemplateInstantiation() || CurContext->isDependentContext();
326  switch (Kind) {
327  case Normal: {
328  // -- the bodies of non-exported nonspecialized template functions
329  // -- the bodies of inline functions
330  if ((IsInNonspecializedTemplate &&
331  !(ManglingContextDecl && isa<ParmVarDecl>(ManglingContextDecl))) ||
332  isInInlineFunction(CurContext)) {
333  ManglingContextDecl = nullptr;
334  while (auto *CD = dyn_cast<CapturedDecl>(DC))
335  DC = CD->getParent();
336  return &Context.getManglingNumberContext(DC);
337  }
338 
339  ManglingContextDecl = nullptr;
340  return nullptr;
341  }
342 
343  case StaticDataMember:
344  // -- the initializers of nonspecialized static members of template classes
345  if (!IsInNonspecializedTemplate) {
346  ManglingContextDecl = nullptr;
347  return nullptr;
348  }
349  // Fall through to get the current context.
350  LLVM_FALLTHROUGH;
351 
352  case DataMember:
353  // -- the in-class initializers of class members
354  case DefaultArgument:
355  // -- default arguments appearing in class definitions
356  case InlineVariable:
357  // -- the initializers of inline variables
358  case VariableTemplate:
359  // -- the initializers of templated variables
360  return &ExprEvalContexts.back().getMangleNumberingContext(Context);
361  }
362 
363  llvm_unreachable("unexpected context");
364 }
365 
368  ASTContext &Ctx) {
369  assert(ManglingContextDecl && "Need to have a context declaration");
370  if (!MangleNumbering)
371  MangleNumbering = Ctx.createMangleNumberingContext();
372  return *MangleNumbering;
373 }
374 
376  SourceRange IntroducerRange,
377  TypeSourceInfo *MethodTypeInfo,
378  SourceLocation EndLoc,
380  const bool IsConstexprSpecified) {
381  QualType MethodType = MethodTypeInfo->getType();
382  TemplateParameterList *TemplateParams =
383  getGenericLambdaTemplateParameterList(getCurLambda(), *this);
384  // If a lambda appears in a dependent context or is a generic lambda (has
385  // template parameters) and has an 'auto' return type, deduce it to a
386  // dependent type.
387  if (Class->isDependentContext() || TemplateParams) {
388  const FunctionProtoType *FPT = MethodType->castAs<FunctionProtoType>();
389  QualType Result = FPT->getReturnType();
390  if (Result->isUndeducedType()) {
391  Result = SubstAutoType(Result, Context.DependentTy);
392  MethodType = Context.getFunctionType(Result, FPT->getParamTypes(),
393  FPT->getExtProtoInfo());
394  }
395  }
396 
397  // C++11 [expr.prim.lambda]p5:
398  // The closure type for a lambda-expression has a public inline function
399  // call operator (13.5.4) whose parameters and return type are described by
400  // the lambda-expression's parameter-declaration-clause and
401  // trailing-return-type respectively.
402  DeclarationName MethodName
403  = Context.DeclarationNames.getCXXOperatorName(OO_Call);
404  DeclarationNameLoc MethodNameLoc;
405  MethodNameLoc.CXXOperatorName.BeginOpNameLoc
406  = IntroducerRange.getBegin().getRawEncoding();
407  MethodNameLoc.CXXOperatorName.EndOpNameLoc
408  = IntroducerRange.getEnd().getRawEncoding();
409  CXXMethodDecl *Method
410  = CXXMethodDecl::Create(Context, Class, EndLoc,
411  DeclarationNameInfo(MethodName,
412  IntroducerRange.getBegin(),
413  MethodNameLoc),
414  MethodType, MethodTypeInfo,
415  SC_None,
416  /*isInline=*/true,
417  IsConstexprSpecified,
418  EndLoc);
419  Method->setAccess(AS_public);
420 
421  // Temporarily set the lexical declaration context to the current
422  // context, so that the Scope stack matches the lexical nesting.
423  Method->setLexicalDeclContext(CurContext);
424  // Create a function template if we have a template parameter list
425  FunctionTemplateDecl *const TemplateMethod = TemplateParams ?
426  FunctionTemplateDecl::Create(Context, Class,
427  Method->getLocation(), MethodName,
428  TemplateParams,
429  Method) : nullptr;
430  if (TemplateMethod) {
431  TemplateMethod->setLexicalDeclContext(CurContext);
432  TemplateMethod->setAccess(AS_public);
433  Method->setDescribedFunctionTemplate(TemplateMethod);
434  }
435 
436  // Add parameters.
437  if (!Params.empty()) {
438  Method->setParams(Params);
439  CheckParmsForFunctionDef(Params,
440  /*CheckParameterNames=*/false);
441 
442  for (auto P : Method->parameters())
443  P->setOwningFunction(Method);
444  }
445 
446  Decl *ManglingContextDecl;
447  if (MangleNumberingContext *MCtx =
448  getCurrentMangleNumberContext(Class->getDeclContext(),
449  ManglingContextDecl)) {
450  unsigned ManglingNumber = MCtx->getManglingNumber(Method);
451  Class->setLambdaMangling(ManglingNumber, ManglingContextDecl);
452  }
453 
454  return Method;
455 }
456 
458  CXXMethodDecl *CallOperator,
459  SourceRange IntroducerRange,
460  LambdaCaptureDefault CaptureDefault,
461  SourceLocation CaptureDefaultLoc,
462  bool ExplicitParams,
463  bool ExplicitResultType,
464  bool Mutable) {
465  LSI->CallOperator = CallOperator;
466  CXXRecordDecl *LambdaClass = CallOperator->getParent();
467  LSI->Lambda = LambdaClass;
468  if (CaptureDefault == LCD_ByCopy)
470  else if (CaptureDefault == LCD_ByRef)
472  LSI->CaptureDefaultLoc = CaptureDefaultLoc;
473  LSI->IntroducerRange = IntroducerRange;
474  LSI->ExplicitParams = ExplicitParams;
475  LSI->Mutable = Mutable;
476 
477  if (ExplicitResultType) {
478  LSI->ReturnType = CallOperator->getReturnType();
479 
480  if (!LSI->ReturnType->isDependentType() &&
481  !LSI->ReturnType->isVoidType()) {
482  if (RequireCompleteType(CallOperator->getLocStart(), LSI->ReturnType,
483  diag::err_lambda_incomplete_result)) {
484  // Do nothing.
485  }
486  }
487  } else {
488  LSI->HasImplicitReturnType = true;
489  }
490 }
491 
494 }
495 
496 void Sema::addLambdaParameters(CXXMethodDecl *CallOperator, Scope *CurScope) {
497  // Introduce our parameters into the function scope
498  for (unsigned p = 0, NumParams = CallOperator->getNumParams();
499  p < NumParams; ++p) {
500  ParmVarDecl *Param = CallOperator->getParamDecl(p);
501 
502  // If this has an identifier, add it to the scope stack.
503  if (CurScope && Param->getIdentifier()) {
504  CheckShadow(CurScope, Param);
505 
506  PushOnScopeChains(Param, CurScope);
507  }
508  }
509 }
510 
511 /// If this expression is an enumerator-like expression of some type
512 /// T, return the type T; otherwise, return null.
513 ///
514 /// Pointer comparisons on the result here should always work because
515 /// it's derived from either the parent of an EnumConstantDecl
516 /// (i.e. the definition) or the declaration returned by
517 /// EnumType::getDecl() (i.e. the definition).
519  // An expression is an enumerator-like expression of type T if,
520  // ignoring parens and parens-like expressions:
521  E = E->IgnoreParens();
522 
523  // - it is an enumerator whose enum type is T or
524  if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
525  if (EnumConstantDecl *D
526  = dyn_cast<EnumConstantDecl>(DRE->getDecl())) {
527  return cast<EnumDecl>(D->getDeclContext());
528  }
529  return nullptr;
530  }
531 
532  // - it is a comma expression whose RHS is an enumerator-like
533  // expression of type T or
534  if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
535  if (BO->getOpcode() == BO_Comma)
536  return findEnumForBlockReturn(BO->getRHS());
537  return nullptr;
538  }
539 
540  // - it is a statement-expression whose value expression is an
541  // enumerator-like expression of type T or
542  if (StmtExpr *SE = dyn_cast<StmtExpr>(E)) {
543  if (Expr *last = dyn_cast_or_null<Expr>(SE->getSubStmt()->body_back()))
544  return findEnumForBlockReturn(last);
545  return nullptr;
546  }
547 
548  // - it is a ternary conditional operator (not the GNU ?:
549  // extension) whose second and third operands are
550  // enumerator-like expressions of type T or
551  if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
552  if (EnumDecl *ED = findEnumForBlockReturn(CO->getTrueExpr()))
553  if (ED == findEnumForBlockReturn(CO->getFalseExpr()))
554  return ED;
555  return nullptr;
556  }
557 
558  // (implicitly:)
559  // - it is an implicit integral conversion applied to an
560  // enumerator-like expression of type T or
561  if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
562  // We can sometimes see integral conversions in valid
563  // enumerator-like expressions.
564  if (ICE->getCastKind() == CK_IntegralCast)
565  return findEnumForBlockReturn(ICE->getSubExpr());
566 
567  // Otherwise, just rely on the type.
568  }
569 
570  // - it is an expression of that formal enum type.
571  if (const EnumType *ET = E->getType()->getAs<EnumType>()) {
572  return ET->getDecl();
573  }
574 
575  // Otherwise, nope.
576  return nullptr;
577 }
578 
579 /// Attempt to find a type T for which the returned expression of the
580 /// given statement is an enumerator-like expression of that type.
582  if (Expr *retValue = ret->getRetValue())
583  return findEnumForBlockReturn(retValue);
584  return nullptr;
585 }
586 
587 /// Attempt to find a common type T for which all of the returned
588 /// expressions in a block are enumerator-like expressions of that
589 /// type.
591  ArrayRef<ReturnStmt*>::iterator i = returns.begin(), e = returns.end();
592 
593  // Try to find one for the first return.
595  if (!ED) return nullptr;
596 
597  // Check that the rest of the returns have the same enum.
598  for (++i; i != e; ++i) {
599  if (findEnumForBlockReturn(*i) != ED)
600  return nullptr;
601  }
602 
603  // Never infer an anonymous enum type.
604  if (!ED->hasNameForLinkage()) return nullptr;
605 
606  return ED;
607 }
608 
609 /// Adjust the given return statements so that they formally return
610 /// the given type. It should require, at most, an IntegralCast.
612  QualType returnType) {
614  i = returns.begin(), e = returns.end(); i != e; ++i) {
615  ReturnStmt *ret = *i;
616  Expr *retValue = ret->getRetValue();
617  if (S.Context.hasSameType(retValue->getType(), returnType))
618  continue;
619 
620  // Right now we only support integral fixup casts.
621  assert(returnType->isIntegralOrUnscopedEnumerationType());
622  assert(retValue->getType()->isIntegralOrUnscopedEnumerationType());
623 
624  ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(retValue);
625 
626  Expr *E = (cleanups ? cleanups->getSubExpr() : retValue);
627  E = ImplicitCastExpr::Create(S.Context, returnType, CK_IntegralCast,
628  E, /*base path*/ nullptr, VK_RValue);
629  if (cleanups) {
630  cleanups->setSubExpr(E);
631  } else {
632  ret->setRetValue(E);
633  }
634  }
635 }
636 
638  assert(CSI.HasImplicitReturnType);
639  // If it was ever a placeholder, it had to been deduced to DependentTy.
640  assert(CSI.ReturnType.isNull() || !CSI.ReturnType->isUndeducedType());
641  assert((!isa<LambdaScopeInfo>(CSI) || !getLangOpts().CPlusPlus14) &&
642  "lambda expressions use auto deduction in C++14 onwards");
643 
644  // C++ core issue 975:
645  // If a lambda-expression does not include a trailing-return-type,
646  // it is as if the trailing-return-type denotes the following type:
647  // - if there are no return statements in the compound-statement,
648  // or all return statements return either an expression of type
649  // void or no expression or braced-init-list, the type void;
650  // - otherwise, if all return statements return an expression
651  // and the types of the returned expressions after
652  // lvalue-to-rvalue conversion (4.1 [conv.lval]),
653  // array-to-pointer conversion (4.2 [conv.array]), and
654  // function-to-pointer conversion (4.3 [conv.func]) are the
655  // same, that common type;
656  // - otherwise, the program is ill-formed.
657  //
658  // C++ core issue 1048 additionally removes top-level cv-qualifiers
659  // from the types of returned expressions to match the C++14 auto
660  // deduction rules.
661  //
662  // In addition, in blocks in non-C++ modes, if all of the return
663  // statements are enumerator-like expressions of some type T, where
664  // T has a name for linkage, then we infer the return type of the
665  // block to be that type.
666 
667  // First case: no return statements, implicit void return type.
668  ASTContext &Ctx = getASTContext();
669  if (CSI.Returns.empty()) {
670  // It's possible there were simply no /valid/ return statements.
671  // In this case, the first one we found may have at least given us a type.
672  if (CSI.ReturnType.isNull())
673  CSI.ReturnType = Ctx.VoidTy;
674  return;
675  }
676 
677  // Second case: at least one return statement has dependent type.
678  // Delay type checking until instantiation.
679  assert(!CSI.ReturnType.isNull() && "We should have a tentative return type.");
680  if (CSI.ReturnType->isDependentType())
681  return;
682 
683  // Try to apply the enum-fuzz rule.
684  if (!getLangOpts().CPlusPlus) {
685  assert(isa<BlockScopeInfo>(CSI));
687  if (ED) {
688  CSI.ReturnType = Context.getTypeDeclType(ED);
690  return;
691  }
692  }
693 
694  // Third case: only one return statement. Don't bother doing extra work!
696  E = CSI.Returns.end();
697  if (I+1 == E)
698  return;
699 
700  // General case: many return statements.
701  // Check that they all have compatible return types.
702 
703  // We require the return types to strictly match here.
704  // Note that we've already done the required promotions as part of
705  // processing the return statement.
706  for (; I != E; ++I) {
707  const ReturnStmt *RS = *I;
708  const Expr *RetE = RS->getRetValue();
709 
710  QualType ReturnType =
711  (RetE ? RetE->getType() : Context.VoidTy).getUnqualifiedType();
712  if (Context.getCanonicalFunctionResultType(ReturnType) ==
714  continue;
715 
716  // FIXME: This is a poor diagnostic for ReturnStmts without expressions.
717  // TODO: It's possible that the *first* return is the divergent one.
718  Diag(RS->getLocStart(),
719  diag::err_typecheck_missing_return_type_incompatible)
720  << ReturnType << CSI.ReturnType
721  << isa<LambdaScopeInfo>(CSI);
722  // Continue iterating so that we keep emitting diagnostics.
723  }
724 }
725 
727  bool ByRef,
729  bool IsDirectInit,
730  Expr *&Init) {
731  // Create an 'auto' or 'auto&' TypeSourceInfo that we can use to
732  // deduce against.
733  QualType DeductType = Context.getAutoDeductType();
734  TypeLocBuilder TLB;
735  TLB.pushTypeSpec(DeductType).setNameLoc(Loc);
736  if (ByRef) {
737  DeductType = BuildReferenceType(DeductType, true, Loc, Id);
738  assert(!DeductType.isNull() && "can't build reference to auto");
739  TLB.push<ReferenceTypeLoc>(DeductType).setSigilLoc(Loc);
740  }
741  TypeSourceInfo *TSI = TLB.getTypeSourceInfo(Context, DeductType);
742 
743  // Deduce the type of the init capture.
744  QualType DeducedType = deduceVarTypeFromInitializer(
745  /*VarDecl*/nullptr, DeclarationName(Id), DeductType, TSI,
746  SourceRange(Loc, Loc), IsDirectInit, Init);
747  if (DeducedType.isNull())
748  return QualType();
749 
750  // Are we a non-list direct initialization?
751  ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
752 
753  // Perform initialization analysis and ensure any implicit conversions
754  // (such as lvalue-to-rvalue) are enforced.
755  InitializedEntity Entity =
756  InitializedEntity::InitializeLambdaCapture(Id, DeducedType, Loc);
758  IsDirectInit
759  ? (CXXDirectInit ? InitializationKind::CreateDirect(
760  Loc, Init->getLocStart(), Init->getLocEnd())
763 
764  MultiExprArg Args = Init;
765  if (CXXDirectInit)
766  Args =
767  MultiExprArg(CXXDirectInit->getExprs(), CXXDirectInit->getNumExprs());
768  QualType DclT;
769  InitializationSequence InitSeq(*this, Entity, Kind, Args);
770  ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
771 
772  if (Result.isInvalid())
773  return QualType();
774  Init = Result.getAs<Expr>();
775 
776  // The init-capture initialization is a full-expression that must be
777  // processed as one before we enter the declcontext of the lambda's
778  // call-operator.
779  Result = ActOnFinishFullExpr(Init, Loc, /*DiscardedValue*/ false,
780  /*IsConstexpr*/ false,
781  /*IsLambdaInitCaptureInitializer*/ true);
782  if (Result.isInvalid())
783  return QualType();
784 
785  Init = Result.getAs<Expr>();
786  return DeducedType;
787 }
788 
790  QualType InitCaptureType,
792  unsigned InitStyle, Expr *Init) {
793  TypeSourceInfo *TSI = Context.getTrivialTypeSourceInfo(InitCaptureType,
794  Loc);
795  // Create a dummy variable representing the init-capture. This is not actually
796  // used as a variable, and only exists as a way to name and refer to the
797  // init-capture.
798  // FIXME: Pass in separate source locations for '&' and identifier.
799  VarDecl *NewVD = VarDecl::Create(Context, CurContext, Loc,
800  Loc, Id, InitCaptureType, TSI, SC_Auto);
801  NewVD->setInitCapture(true);
802  NewVD->setReferenced(true);
803  // FIXME: Pass in a VarDecl::InitializationStyle.
804  NewVD->setInitStyle(static_cast<VarDecl::InitializationStyle>(InitStyle));
805  NewVD->markUsed(Context);
806  NewVD->setInit(Init);
807  return NewVD;
808 }
809 
811  FieldDecl *Field = FieldDecl::Create(
812  Context, LSI->Lambda, Var->getLocation(), Var->getLocation(),
813  nullptr, Var->getType(), Var->getTypeSourceInfo(), nullptr, false,
814  ICIS_NoInit);
815  Field->setImplicit(true);
816  Field->setAccess(AS_private);
817  LSI->Lambda->addDecl(Field);
818 
819  LSI->addCapture(Var, /*isBlock*/false, Var->getType()->isReferenceType(),
820  /*isNested*/false, Var->getLocation(), SourceLocation(),
821  Var->getType(), Var->getInit());
822  return Field;
823 }
824 
826  Declarator &ParamInfo,
827  Scope *CurScope) {
828  // Determine if we're within a context where we know that the lambda will
829  // be dependent, because there are template parameters in scope.
830  bool KnownDependent = false;
831  LambdaScopeInfo *const LSI = getCurLambda();
832  assert(LSI && "LambdaScopeInfo should be on stack!");
833 
834  // The lambda-expression's closure type might be dependent even if its
835  // semantic context isn't, if it appears within a default argument of a
836  // function template.
837  if (CurScope->getTemplateParamParent())
838  KnownDependent = true;
839 
840  // Determine the signature of the call operator.
841  TypeSourceInfo *MethodTyInfo;
842  bool ExplicitParams = true;
843  bool ExplicitResultType = true;
844  bool ContainsUnexpandedParameterPack = false;
845  SourceLocation EndLoc;
847  if (ParamInfo.getNumTypeObjects() == 0) {
848  // C++11 [expr.prim.lambda]p4:
849  // If a lambda-expression does not include a lambda-declarator, it is as
850  // if the lambda-declarator were ().
852  /*IsVariadic=*/false, /*IsCXXMethod=*/true));
853  EPI.HasTrailingReturn = true;
854  EPI.TypeQuals |= DeclSpec::TQ_const;
855  // C++1y [expr.prim.lambda]:
856  // The lambda return type is 'auto', which is replaced by the
857  // trailing-return type if provided and/or deduced from 'return'
858  // statements
859  // We don't do this before C++1y, because we don't support deduced return
860  // types there.
861  QualType DefaultTypeForNoTrailingReturn =
862  getLangOpts().CPlusPlus14 ? Context.getAutoDeductType()
863  : Context.DependentTy;
864  QualType MethodTy =
865  Context.getFunctionType(DefaultTypeForNoTrailingReturn, None, EPI);
866  MethodTyInfo = Context.getTrivialTypeSourceInfo(MethodTy);
867  ExplicitParams = false;
868  ExplicitResultType = false;
869  EndLoc = Intro.Range.getEnd();
870  } else {
871  assert(ParamInfo.isFunctionDeclarator() &&
872  "lambda-declarator is a function");
874 
875  // C++11 [expr.prim.lambda]p5:
876  // This function call operator is declared const (9.3.1) if and only if
877  // the lambda-expression's parameter-declaration-clause is not followed
878  // by mutable. It is neither virtual nor declared volatile. [...]
879  if (!FTI.hasMutableQualifier())
881 
882  MethodTyInfo = GetTypeForDeclarator(ParamInfo, CurScope);
883  assert(MethodTyInfo && "no type from lambda-declarator");
884  EndLoc = ParamInfo.getSourceRange().getEnd();
885 
886  ExplicitResultType = FTI.hasTrailingReturnType();
887 
888  if (FTIHasNonVoidParameters(FTI)) {
889  Params.reserve(FTI.NumParams);
890  for (unsigned i = 0, e = FTI.NumParams; i != e; ++i)
891  Params.push_back(cast<ParmVarDecl>(FTI.Params[i].Param));
892  }
893 
894  // Check for unexpanded parameter packs in the method type.
895  if (MethodTyInfo->getType()->containsUnexpandedParameterPack())
896  ContainsUnexpandedParameterPack = true;
897  }
898 
899  CXXRecordDecl *Class = createLambdaClosureType(Intro.Range, MethodTyInfo,
900  KnownDependent, Intro.Default);
901 
902  CXXMethodDecl *Method =
903  startLambdaDefinition(Class, Intro.Range, MethodTyInfo, EndLoc, Params,
904  ParamInfo.getDeclSpec().isConstexprSpecified());
905  if (ExplicitParams)
906  CheckCXXDefaultArguments(Method);
907 
908  // Attributes on the lambda apply to the method.
909  ProcessDeclAttributes(CurScope, Method, ParamInfo);
910 
911  // CUDA lambdas get implicit attributes based on the scope in which they're
912  // declared.
913  if (getLangOpts().CUDA)
914  CUDASetLambdaAttrs(Method);
915 
916  // Introduce the function call operator as the current declaration context.
917  PushDeclContext(CurScope, Method);
918 
919  // Build the lambda scope.
920  buildLambdaScope(LSI, Method, Intro.Range, Intro.Default, Intro.DefaultLoc,
921  ExplicitParams, ExplicitResultType, !Method->isConst());
922 
923  // C++11 [expr.prim.lambda]p9:
924  // A lambda-expression whose smallest enclosing scope is a block scope is a
925  // local lambda expression; any other lambda expression shall not have a
926  // capture-default or simple-capture in its lambda-introducer.
927  //
928  // For simple-captures, this is covered by the check below that any named
929  // entity is a variable that can be captured.
930  //
931  // For DR1632, we also allow a capture-default in any context where we can
932  // odr-use 'this' (in particular, in a default initializer for a non-static
933  // data member).
934  if (Intro.Default != LCD_None && !Class->getParent()->isFunctionOrMethod() &&
935  (getCurrentThisType().isNull() ||
936  CheckCXXThisCapture(SourceLocation(), /*Explicit*/true,
937  /*BuildAndDiagnose*/false)))
938  Diag(Intro.DefaultLoc, diag::err_capture_default_non_local);
939 
940  // Distinct capture names, for diagnostics.
941  llvm::SmallSet<IdentifierInfo*, 8> CaptureNames;
942 
943  // Handle explicit captures.
944  SourceLocation PrevCaptureLoc
945  = Intro.Default == LCD_None? Intro.Range.getBegin() : Intro.DefaultLoc;
946  for (auto C = Intro.Captures.begin(), E = Intro.Captures.end(); C != E;
947  PrevCaptureLoc = C->Loc, ++C) {
948  if (C->Kind == LCK_This || C->Kind == LCK_StarThis) {
949  if (C->Kind == LCK_StarThis)
950  Diag(C->Loc, !getLangOpts().CPlusPlus17
951  ? diag::ext_star_this_lambda_capture_cxx17
952  : diag::warn_cxx14_compat_star_this_lambda_capture);
953 
954  // C++11 [expr.prim.lambda]p8:
955  // An identifier or this shall not appear more than once in a
956  // lambda-capture.
957  if (LSI->isCXXThisCaptured()) {
958  Diag(C->Loc, diag::err_capture_more_than_once)
959  << "'this'" << SourceRange(LSI->getCXXThisCapture().getLocation())
961  SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
962  continue;
963  }
964 
965  // C++2a [expr.prim.lambda]p8:
966  // If a lambda-capture includes a capture-default that is =,
967  // each simple-capture of that lambda-capture shall be of the form
968  // "&identifier", "this", or "* this". [ Note: The form [&,this] is
969  // redundant but accepted for compatibility with ISO C++14. --end note ]
970  if (Intro.Default == LCD_ByCopy && C->Kind != LCK_StarThis)
971  Diag(C->Loc, !getLangOpts().CPlusPlus2a
972  ? diag::ext_equals_this_lambda_capture_cxx2a
973  : diag::warn_cxx17_compat_equals_this_lambda_capture);
974 
975  // C++11 [expr.prim.lambda]p12:
976  // If this is captured by a local lambda expression, its nearest
977  // enclosing function shall be a non-static member function.
978  QualType ThisCaptureType = getCurrentThisType();
979  if (ThisCaptureType.isNull()) {
980  Diag(C->Loc, diag::err_this_capture) << true;
981  continue;
982  }
983 
984  CheckCXXThisCapture(C->Loc, /*Explicit=*/true, /*BuildAndDiagnose*/ true,
985  /*FunctionScopeIndexToStopAtPtr*/ nullptr,
986  C->Kind == LCK_StarThis);
987  continue;
988  }
989 
990  assert(C->Id && "missing identifier for capture");
991 
992  if (C->Init.isInvalid())
993  continue;
994 
995  VarDecl *Var = nullptr;
996  if (C->Init.isUsable()) {
997  Diag(C->Loc, getLangOpts().CPlusPlus14
998  ? diag::warn_cxx11_compat_init_capture
999  : diag::ext_init_capture);
1000 
1001  if (C->Init.get()->containsUnexpandedParameterPack())
1002  ContainsUnexpandedParameterPack = true;
1003  // If the initializer expression is usable, but the InitCaptureType
1004  // is not, then an error has occurred - so ignore the capture for now.
1005  // for e.g., [n{0}] { }; <-- if no <initializer_list> is included.
1006  // FIXME: we should create the init capture variable and mark it invalid
1007  // in this case.
1008  if (C->InitCaptureType.get().isNull())
1009  continue;
1010 
1011  unsigned InitStyle;
1012  switch (C->InitKind) {
1014  llvm_unreachable("not an init-capture?");
1016  InitStyle = VarDecl::CInit;
1017  break;
1019  InitStyle = VarDecl::CallInit;
1020  break;
1022  InitStyle = VarDecl::ListInit;
1023  break;
1024  }
1025  Var = createLambdaInitCaptureVarDecl(C->Loc, C->InitCaptureType.get(),
1026  C->Id, InitStyle, C->Init.get());
1027  // C++1y [expr.prim.lambda]p11:
1028  // An init-capture behaves as if it declares and explicitly
1029  // captures a variable [...] whose declarative region is the
1030  // lambda-expression's compound-statement
1031  if (Var)
1032  PushOnScopeChains(Var, CurScope, false);
1033  } else {
1034  assert(C->InitKind == LambdaCaptureInitKind::NoInit &&
1035  "init capture has valid but null init?");
1036 
1037  // C++11 [expr.prim.lambda]p8:
1038  // If a lambda-capture includes a capture-default that is &, the
1039  // identifiers in the lambda-capture shall not be preceded by &.
1040  // If a lambda-capture includes a capture-default that is =, [...]
1041  // each identifier it contains shall be preceded by &.
1042  if (C->Kind == LCK_ByRef && Intro.Default == LCD_ByRef) {
1043  Diag(C->Loc, diag::err_reference_capture_with_reference_default)
1045  SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
1046  continue;
1047  } else if (C->Kind == LCK_ByCopy && Intro.Default == LCD_ByCopy) {
1048  Diag(C->Loc, diag::err_copy_capture_with_copy_default)
1050  SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
1051  continue;
1052  }
1053 
1054  // C++11 [expr.prim.lambda]p10:
1055  // The identifiers in a capture-list are looked up using the usual
1056  // rules for unqualified name lookup (3.4.1)
1057  DeclarationNameInfo Name(C->Id, C->Loc);
1058  LookupResult R(*this, Name, LookupOrdinaryName);
1059  LookupName(R, CurScope);
1060  if (R.isAmbiguous())
1061  continue;
1062  if (R.empty()) {
1063  // FIXME: Disable corrections that would add qualification?
1064  CXXScopeSpec ScopeSpec;
1065  if (DiagnoseEmptyLookup(CurScope, ScopeSpec, R,
1066  llvm::make_unique<DeclFilterCCC<VarDecl>>()))
1067  continue;
1068  }
1069 
1070  Var = R.getAsSingle<VarDecl>();
1071  if (Var && DiagnoseUseOfDecl(Var, C->Loc))
1072  continue;
1073  }
1074 
1075  // C++11 [expr.prim.lambda]p8:
1076  // An identifier or this shall not appear more than once in a
1077  // lambda-capture.
1078  if (!CaptureNames.insert(C->Id).second) {
1079  if (Var && LSI->isCaptured(Var)) {
1080  Diag(C->Loc, diag::err_capture_more_than_once)
1081  << C->Id << SourceRange(LSI->getCapture(Var).getLocation())
1083  SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
1084  } else
1085  // Previous capture captured something different (one or both was
1086  // an init-cpature): no fixit.
1087  Diag(C->Loc, diag::err_capture_more_than_once) << C->Id;
1088  continue;
1089  }
1090 
1091  // C++11 [expr.prim.lambda]p10:
1092  // [...] each such lookup shall find a variable with automatic storage
1093  // duration declared in the reaching scope of the local lambda expression.
1094  // Note that the 'reaching scope' check happens in tryCaptureVariable().
1095  if (!Var) {
1096  Diag(C->Loc, diag::err_capture_does_not_name_variable) << C->Id;
1097  continue;
1098  }
1099 
1100  // Ignore invalid decls; they'll just confuse the code later.
1101  if (Var->isInvalidDecl())
1102  continue;
1103 
1104  if (!Var->hasLocalStorage()) {
1105  Diag(C->Loc, diag::err_capture_non_automatic_variable) << C->Id;
1106  Diag(Var->getLocation(), diag::note_previous_decl) << C->Id;
1107  continue;
1108  }
1109 
1110  // C++11 [expr.prim.lambda]p23:
1111  // A capture followed by an ellipsis is a pack expansion (14.5.3).
1112  SourceLocation EllipsisLoc;
1113  if (C->EllipsisLoc.isValid()) {
1114  if (Var->isParameterPack()) {
1115  EllipsisLoc = C->EllipsisLoc;
1116  } else {
1117  Diag(C->EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
1118  << SourceRange(C->Loc);
1119 
1120  // Just ignore the ellipsis.
1121  }
1122  } else if (Var->isParameterPack()) {
1123  ContainsUnexpandedParameterPack = true;
1124  }
1125 
1126  if (C->Init.isUsable()) {
1127  buildInitCaptureField(LSI, Var);
1128  } else {
1129  TryCaptureKind Kind = C->Kind == LCK_ByRef ? TryCapture_ExplicitByRef :
1130  TryCapture_ExplicitByVal;
1131  tryCaptureVariable(Var, C->Loc, Kind, EllipsisLoc);
1132  }
1133  }
1134  finishLambdaExplicitCaptures(LSI);
1135 
1136  LSI->ContainsUnexpandedParameterPack = ContainsUnexpandedParameterPack;
1137 
1138  // Add lambda parameters into scope.
1139  addLambdaParameters(Method, CurScope);
1140 
1141  // Enter a new evaluation context to insulate the lambda from any
1142  // cleanups from the enclosing full-expression.
1143  PushExpressionEvaluationContext(
1144  ExpressionEvaluationContext::PotentiallyEvaluated);
1145 }
1146 
1148  bool IsInstantiation) {
1149  LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(FunctionScopes.back());
1150 
1151  // Leave the expression-evaluation context.
1152  DiscardCleanupsInEvaluationContext();
1153  PopExpressionEvaluationContext();
1154 
1155  // Leave the context of the lambda.
1156  if (!IsInstantiation)
1157  PopDeclContext();
1158 
1159  // Finalize the lambda.
1160  CXXRecordDecl *Class = LSI->Lambda;
1161  Class->setInvalidDecl();
1162  SmallVector<Decl*, 4> Fields(Class->fields());
1163  ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
1164  SourceLocation(), nullptr);
1165  CheckCompletedCXXClass(Class);
1166 
1167  PopFunctionScopeInfo();
1168 }
1169 
1170 /// \brief Add a lambda's conversion to function pointer, as described in
1171 /// C++11 [expr.prim.lambda]p6.
1173  SourceRange IntroducerRange,
1174  CXXRecordDecl *Class,
1175  CXXMethodDecl *CallOperator) {
1176  // This conversion is explicitly disabled if the lambda's function has
1177  // pass_object_size attributes on any of its parameters.
1178  auto HasPassObjectSizeAttr = [](const ParmVarDecl *P) {
1179  return P->hasAttr<PassObjectSizeAttr>();
1180  };
1181  if (llvm::any_of(CallOperator->parameters(), HasPassObjectSizeAttr))
1182  return;
1183 
1184  // Add the conversion to function pointer.
1185  const FunctionProtoType *CallOpProto =
1186  CallOperator->getType()->getAs<FunctionProtoType>();
1187  const FunctionProtoType::ExtProtoInfo CallOpExtInfo =
1188  CallOpProto->getExtProtoInfo();
1189  QualType PtrToFunctionTy;
1190  QualType InvokerFunctionTy;
1191  {
1192  FunctionProtoType::ExtProtoInfo InvokerExtInfo = CallOpExtInfo;
1194  CallOpProto->isVariadic(), /*IsCXXMethod=*/false);
1195  InvokerExtInfo.ExtInfo = InvokerExtInfo.ExtInfo.withCallingConv(CC);
1196  InvokerExtInfo.TypeQuals = 0;
1197  assert(InvokerExtInfo.RefQualifier == RQ_None &&
1198  "Lambda's call operator should not have a reference qualifier");
1199  InvokerFunctionTy =
1200  S.Context.getFunctionType(CallOpProto->getReturnType(),
1201  CallOpProto->getParamTypes(), InvokerExtInfo);
1202  PtrToFunctionTy = S.Context.getPointerType(InvokerFunctionTy);
1203  }
1204 
1205  // Create the type of the conversion function.
1206  FunctionProtoType::ExtProtoInfo ConvExtInfo(
1208  /*IsVariadic=*/false, /*IsCXXMethod=*/true));
1209  // The conversion function is always const.
1210  ConvExtInfo.TypeQuals = Qualifiers::Const;
1211  QualType ConvTy =
1212  S.Context.getFunctionType(PtrToFunctionTy, None, ConvExtInfo);
1213 
1214  SourceLocation Loc = IntroducerRange.getBegin();
1215  DeclarationName ConversionName
1217  S.Context.getCanonicalType(PtrToFunctionTy));
1218  DeclarationNameLoc ConvNameLoc;
1219  // Construct a TypeSourceInfo for the conversion function, and wire
1220  // all the parameters appropriately for the FunctionProtoTypeLoc
1221  // so that everything works during transformation/instantiation of
1222  // generic lambdas.
1223  // The main reason for wiring up the parameters of the conversion
1224  // function with that of the call operator is so that constructs
1225  // like the following work:
1226  // auto L = [](auto b) { <-- 1
1227  // return [](auto a) -> decltype(a) { <-- 2
1228  // return a;
1229  // };
1230  // };
1231  // int (*fp)(int) = L(5);
1232  // Because the trailing return type can contain DeclRefExprs that refer
1233  // to the original call operator's variables, we hijack the call
1234  // operators ParmVarDecls below.
1235  TypeSourceInfo *ConvNamePtrToFunctionTSI =
1236  S.Context.getTrivialTypeSourceInfo(PtrToFunctionTy, Loc);
1237  ConvNameLoc.NamedType.TInfo = ConvNamePtrToFunctionTSI;
1238 
1239  // The conversion function is a conversion to a pointer-to-function.
1240  TypeSourceInfo *ConvTSI = S.Context.getTrivialTypeSourceInfo(ConvTy, Loc);
1241  FunctionProtoTypeLoc ConvTL =
1242  ConvTSI->getTypeLoc().getAs<FunctionProtoTypeLoc>();
1243  // Get the result of the conversion function which is a pointer-to-function.
1244  PointerTypeLoc PtrToFunctionTL =
1245  ConvTL.getReturnLoc().getAs<PointerTypeLoc>();
1246  // Do the same for the TypeSourceInfo that is used to name the conversion
1247  // operator.
1248  PointerTypeLoc ConvNamePtrToFunctionTL =
1249  ConvNamePtrToFunctionTSI->getTypeLoc().getAs<PointerTypeLoc>();
1250 
1251  // Get the underlying function types that the conversion function will
1252  // be converting to (should match the type of the call operator).
1253  FunctionProtoTypeLoc CallOpConvTL =
1254  PtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();
1255  FunctionProtoTypeLoc CallOpConvNameTL =
1256  ConvNamePtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();
1257 
1258  // Wire up the FunctionProtoTypeLocs with the call operator's parameters.
1259  // These parameter's are essentially used to transform the name and
1260  // the type of the conversion operator. By using the same parameters
1261  // as the call operator's we don't have to fix any back references that
1262  // the trailing return type of the call operator's uses (such as
1263  // decltype(some_type<decltype(a)>::type{} + decltype(a){}) etc.)
1264  // - we can simply use the return type of the call operator, and
1265  // everything should work.
1266  SmallVector<ParmVarDecl *, 4> InvokerParams;
1267  for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I) {
1268  ParmVarDecl *From = CallOperator->getParamDecl(I);
1269 
1270  InvokerParams.push_back(ParmVarDecl::Create(S.Context,
1271  // Temporarily add to the TU. This is set to the invoker below.
1273  From->getLocStart(),
1274  From->getLocation(),
1275  From->getIdentifier(),
1276  From->getType(),
1277  From->getTypeSourceInfo(),
1278  From->getStorageClass(),
1279  /*DefaultArg=*/nullptr));
1280  CallOpConvTL.setParam(I, From);
1281  CallOpConvNameTL.setParam(I, From);
1282  }
1283 
1284  CXXConversionDecl *Conversion
1285  = CXXConversionDecl::Create(S.Context, Class, Loc,
1286  DeclarationNameInfo(ConversionName,
1287  Loc, ConvNameLoc),
1288  ConvTy,
1289  ConvTSI,
1290  /*isInline=*/true, /*isExplicit=*/false,
1291  /*isConstexpr=*/S.getLangOpts().CPlusPlus17,
1292  CallOperator->getBody()->getLocEnd());
1293  Conversion->setAccess(AS_public);
1294  Conversion->setImplicit(true);
1295 
1296  if (Class->isGenericLambda()) {
1297  // Create a template version of the conversion operator, using the template
1298  // parameter list of the function call operator.
1299  FunctionTemplateDecl *TemplateCallOperator =
1300  CallOperator->getDescribedFunctionTemplate();
1301  FunctionTemplateDecl *ConversionTemplate =
1303  Loc, ConversionName,
1304  TemplateCallOperator->getTemplateParameters(),
1305  Conversion);
1306  ConversionTemplate->setAccess(AS_public);
1307  ConversionTemplate->setImplicit(true);
1308  Conversion->setDescribedFunctionTemplate(ConversionTemplate);
1309  Class->addDecl(ConversionTemplate);
1310  } else
1311  Class->addDecl(Conversion);
1312  // Add a non-static member function that will be the result of
1313  // the conversion with a certain unique ID.
1314  DeclarationName InvokerName = &S.Context.Idents.get(
1316  // FIXME: Instead of passing in the CallOperator->getTypeSourceInfo()
1317  // we should get a prebuilt TrivialTypeSourceInfo from Context
1318  // using FunctionTy & Loc and get its TypeLoc as a FunctionProtoTypeLoc
1319  // then rewire the parameters accordingly, by hoisting up the InvokeParams
1320  // loop below and then use its Params to set Invoke->setParams(...) below.
1321  // This would avoid the 'const' qualifier of the calloperator from
1322  // contaminating the type of the invoker, which is currently adjusted
1323  // in SemaTemplateDeduction.cpp:DeduceTemplateArguments. Fixing the
1324  // trailing return type of the invoker would require a visitor to rebuild
1325  // the trailing return type and adjusting all back DeclRefExpr's to refer
1326  // to the new static invoker parameters - not the call operator's.
1327  CXXMethodDecl *Invoke
1328  = CXXMethodDecl::Create(S.Context, Class, Loc,
1329  DeclarationNameInfo(InvokerName, Loc),
1330  InvokerFunctionTy,
1331  CallOperator->getTypeSourceInfo(),
1332  SC_Static, /*IsInline=*/true,
1333  /*IsConstexpr=*/false,
1334  CallOperator->getBody()->getLocEnd());
1335  for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I)
1336  InvokerParams[I]->setOwningFunction(Invoke);
1337  Invoke->setParams(InvokerParams);
1338  Invoke->setAccess(AS_private);
1339  Invoke->setImplicit(true);
1340  if (Class->isGenericLambda()) {
1341  FunctionTemplateDecl *TemplateCallOperator =
1342  CallOperator->getDescribedFunctionTemplate();
1343  FunctionTemplateDecl *StaticInvokerTemplate = FunctionTemplateDecl::Create(
1344  S.Context, Class, Loc, InvokerName,
1345  TemplateCallOperator->getTemplateParameters(),
1346  Invoke);
1347  StaticInvokerTemplate->setAccess(AS_private);
1348  StaticInvokerTemplate->setImplicit(true);
1349  Invoke->setDescribedFunctionTemplate(StaticInvokerTemplate);
1350  Class->addDecl(StaticInvokerTemplate);
1351  } else
1352  Class->addDecl(Invoke);
1353 }
1354 
1355 /// \brief Add a lambda's conversion to block pointer.
1357  SourceRange IntroducerRange,
1358  CXXRecordDecl *Class,
1359  CXXMethodDecl *CallOperator) {
1360  const FunctionProtoType *Proto =
1361  CallOperator->getType()->getAs<FunctionProtoType>();
1362 
1363  // The function type inside the block pointer type is the same as the call
1364  // operator with some tweaks. The calling convention is the default free
1365  // function convention, and the type qualifications are lost.
1367  BlockEPI.ExtInfo =
1368  BlockEPI.ExtInfo.withCallingConv(S.Context.getDefaultCallingConvention(
1369  Proto->isVariadic(), /*IsCXXMethod=*/false));
1370  BlockEPI.TypeQuals = 0;
1371  QualType FunctionTy = S.Context.getFunctionType(
1372  Proto->getReturnType(), Proto->getParamTypes(), BlockEPI);
1373  QualType BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);
1374 
1375  FunctionProtoType::ExtProtoInfo ConversionEPI(
1377  /*IsVariadic=*/false, /*IsCXXMethod=*/true));
1378  ConversionEPI.TypeQuals = Qualifiers::Const;
1379  QualType ConvTy = S.Context.getFunctionType(BlockPtrTy, None, ConversionEPI);
1380 
1381  SourceLocation Loc = IntroducerRange.getBegin();
1382  DeclarationName Name
1384  S.Context.getCanonicalType(BlockPtrTy));
1385  DeclarationNameLoc NameLoc;
1386  NameLoc.NamedType.TInfo = S.Context.getTrivialTypeSourceInfo(BlockPtrTy, Loc);
1387  CXXConversionDecl *Conversion
1388  = CXXConversionDecl::Create(S.Context, Class, Loc,
1389  DeclarationNameInfo(Name, Loc, NameLoc),
1390  ConvTy,
1391  S.Context.getTrivialTypeSourceInfo(ConvTy, Loc),
1392  /*isInline=*/true, /*isExplicit=*/false,
1393  /*isConstexpr=*/false,
1394  CallOperator->getBody()->getLocEnd());
1395  Conversion->setAccess(AS_public);
1396  Conversion->setImplicit(true);
1397  Class->addDecl(Conversion);
1398 }
1399 
1401  Sema &S, const LambdaScopeInfo::Capture &Capture, FieldDecl *Field) {
1402  assert(Capture.isVariableCapture() && "not a variable capture");
1403 
1404  auto *Var = Capture.getVariable();
1405  SourceLocation Loc = Capture.getLocation();
1406 
1407  // C++11 [expr.prim.lambda]p21:
1408  // When the lambda-expression is evaluated, the entities that
1409  // are captured by copy are used to direct-initialize each
1410  // corresponding non-static data member of the resulting closure
1411  // object. (For array members, the array elements are
1412  // direct-initialized in increasing subscript order.) These
1413  // initializations are performed in the (unspecified) order in
1414  // which the non-static data members are declared.
1415 
1416  // C++ [expr.prim.lambda]p12:
1417  // An entity captured by a lambda-expression is odr-used (3.2) in
1418  // the scope containing the lambda-expression.
1419  ExprResult RefResult = S.BuildDeclarationNameExpr(
1420  CXXScopeSpec(), DeclarationNameInfo(Var->getDeclName(), Loc), Var);
1421  if (RefResult.isInvalid())
1422  return ExprError();
1423  Expr *Ref = RefResult.get();
1424 
1426  Var->getIdentifier(), Field->getType(), Loc);
1427  InitializationKind InitKind = InitializationKind::CreateDirect(Loc, Loc, Loc);
1428  InitializationSequence Init(S, Entity, InitKind, Ref);
1429  return Init.Perform(S, Entity, InitKind, Ref);
1430 }
1431 
1433  Scope *CurScope) {
1434  LambdaScopeInfo LSI = *cast<LambdaScopeInfo>(FunctionScopes.back());
1435  ActOnFinishFunctionBody(LSI.CallOperator, Body);
1436  return BuildLambdaExpr(StartLoc, Body->getLocEnd(), &LSI);
1437 }
1438 
1439 static LambdaCaptureDefault
1441  switch (ICS) {
1443  return LCD_None;
1445  return LCD_ByCopy;
1448  return LCD_ByRef;
1450  llvm_unreachable("block capture in lambda");
1451  }
1452  llvm_unreachable("Unknown implicit capture style");
1453 }
1454 
1455 bool Sema::CaptureHasSideEffects(const LambdaScopeInfo::Capture &From) {
1456  if (!From.isVLATypeCapture()) {
1457  Expr *Init = From.getInitExpr();
1458  if (Init && Init->HasSideEffects(Context))
1459  return true;
1460  }
1461 
1462  if (!From.isCopyCapture())
1463  return false;
1464 
1465  const QualType T = From.isThisCapture()
1466  ? getCurrentThisType()->getPointeeType()
1467  : From.getCaptureType();
1468 
1469  if (T.isVolatileQualified())
1470  return true;
1471 
1472  const Type *BaseT = T->getBaseElementTypeUnsafe();
1473  if (const CXXRecordDecl *RD = BaseT->getAsCXXRecordDecl())
1474  return !RD->isCompleteDefinition() || !RD->hasTrivialCopyConstructor() ||
1475  !RD->hasTrivialDestructor();
1476 
1477  return false;
1478 }
1479 
1480 void Sema::DiagnoseUnusedLambdaCapture(const LambdaScopeInfo::Capture &From) {
1481  if (CaptureHasSideEffects(From))
1482  return;
1483 
1484  if (From.isVLATypeCapture())
1485  return;
1486 
1487  auto diag = Diag(From.getLocation(), diag::warn_unused_lambda_capture);
1488  if (From.isThisCapture())
1489  diag << "'this'";
1490  else
1491  diag << From.getVariable();
1492  diag << From.isNonODRUsed();
1493 }
1494 
1496  LambdaScopeInfo *LSI) {
1497  // Collect information from the lambda scope.
1499  SmallVector<Expr *, 4> CaptureInits;
1500  SourceLocation CaptureDefaultLoc = LSI->CaptureDefaultLoc;
1501  LambdaCaptureDefault CaptureDefault =
1503  CXXRecordDecl *Class;
1504  CXXMethodDecl *CallOperator;
1505  SourceRange IntroducerRange;
1506  bool ExplicitParams;
1507  bool ExplicitResultType;
1508  CleanupInfo LambdaCleanup;
1509  bool ContainsUnexpandedParameterPack;
1510  bool IsGenericLambda;
1511  {
1512  CallOperator = LSI->CallOperator;
1513  Class = LSI->Lambda;
1514  IntroducerRange = LSI->IntroducerRange;
1515  ExplicitParams = LSI->ExplicitParams;
1516  ExplicitResultType = !LSI->HasImplicitReturnType;
1517  LambdaCleanup = LSI->Cleanup;
1518  ContainsUnexpandedParameterPack = LSI->ContainsUnexpandedParameterPack;
1519  IsGenericLambda = Class->isGenericLambda();
1520 
1521  CallOperator->setLexicalDeclContext(Class);
1522  Decl *TemplateOrNonTemplateCallOperatorDecl =
1523  CallOperator->getDescribedFunctionTemplate()
1524  ? CallOperator->getDescribedFunctionTemplate()
1525  : cast<Decl>(CallOperator);
1526 
1527  TemplateOrNonTemplateCallOperatorDecl->setLexicalDeclContext(Class);
1528  Class->addDecl(TemplateOrNonTemplateCallOperatorDecl);
1529 
1530  PopExpressionEvaluationContext();
1531 
1532  // Translate captures.
1533  auto CurField = Class->field_begin();
1534  for (unsigned I = 0, N = LSI->Captures.size(); I != N; ++I, ++CurField) {
1535  const LambdaScopeInfo::Capture &From = LSI->Captures[I];
1536  assert(!From.isBlockCapture() && "Cannot capture __block variables");
1537  bool IsImplicit = I >= LSI->NumExplicitCaptures;
1538 
1539  // Warn about unused explicit captures.
1540  if (!CurContext->isDependentContext() && !IsImplicit && !From.isODRUsed()) {
1541  // Initialized captures that are non-ODR used may not be eliminated.
1542  bool NonODRUsedInitCapture =
1543  IsGenericLambda && From.isNonODRUsed() && From.getInitExpr();
1544  if (!NonODRUsedInitCapture)
1545  DiagnoseUnusedLambdaCapture(From);
1546  }
1547 
1548  // Handle 'this' capture.
1549  if (From.isThisCapture()) {
1550  Captures.push_back(
1551  LambdaCapture(From.getLocation(), IsImplicit,
1552  From.isCopyCapture() ? LCK_StarThis : LCK_This));
1553  CaptureInits.push_back(From.getInitExpr());
1554  continue;
1555  }
1556  if (From.isVLATypeCapture()) {
1557  Captures.push_back(
1558  LambdaCapture(From.getLocation(), IsImplicit, LCK_VLAType));
1559  CaptureInits.push_back(nullptr);
1560  continue;
1561  }
1562 
1563  VarDecl *Var = From.getVariable();
1564  LambdaCaptureKind Kind = From.isCopyCapture() ? LCK_ByCopy : LCK_ByRef;
1565  Captures.push_back(LambdaCapture(From.getLocation(), IsImplicit, Kind,
1566  Var, From.getEllipsisLoc()));
1567  Expr *Init = From.getInitExpr();
1568  if (!Init) {
1569  auto InitResult =
1570  performLambdaVarCaptureInitialization(*this, From, *CurField);
1571  if (InitResult.isInvalid())
1572  return ExprError();
1573  Init = InitResult.get();
1574  }
1575  CaptureInits.push_back(Init);
1576  }
1577 
1578  // C++11 [expr.prim.lambda]p6:
1579  // The closure type for a lambda-expression with no lambda-capture
1580  // has a public non-virtual non-explicit const conversion function
1581  // to pointer to function having the same parameter and return
1582  // types as the closure type's function call operator.
1583  if (Captures.empty() && CaptureDefault == LCD_None)
1584  addFunctionPointerConversion(*this, IntroducerRange, Class,
1585  CallOperator);
1586 
1587  // Objective-C++:
1588  // The closure type for a lambda-expression has a public non-virtual
1589  // non-explicit const conversion function to a block pointer having the
1590  // same parameter and return types as the closure type's function call
1591  // operator.
1592  // FIXME: Fix generic lambda to block conversions.
1593  if (getLangOpts().Blocks && getLangOpts().ObjC1 && !IsGenericLambda)
1594  addBlockPointerConversion(*this, IntroducerRange, Class, CallOperator);
1595 
1596  // Finalize the lambda class.
1597  SmallVector<Decl*, 4> Fields(Class->fields());
1598  ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
1599  SourceLocation(), nullptr);
1600  CheckCompletedCXXClass(Class);
1601  }
1602 
1603  Cleanup.mergeFrom(LambdaCleanup);
1604 
1605  LambdaExpr *Lambda = LambdaExpr::Create(Context, Class, IntroducerRange,
1606  CaptureDefault, CaptureDefaultLoc,
1607  Captures,
1608  ExplicitParams, ExplicitResultType,
1609  CaptureInits, EndLoc,
1610  ContainsUnexpandedParameterPack);
1611  // If the lambda expression's call operator is not explicitly marked constexpr
1612  // and we are not in a dependent context, analyze the call operator to infer
1613  // its constexpr-ness, suppressing diagnostics while doing so.
1614  if (getLangOpts().CPlusPlus17 && !CallOperator->isInvalidDecl() &&
1615  !CallOperator->isConstexpr() &&
1616  !isa<CoroutineBodyStmt>(CallOperator->getBody()) &&
1617  !Class->getDeclContext()->isDependentContext()) {
1618  TentativeAnalysisScope DiagnosticScopeGuard(*this);
1619  CallOperator->setConstexpr(
1620  CheckConstexprFunctionDecl(CallOperator) &&
1621  CheckConstexprFunctionBody(CallOperator, CallOperator->getBody()));
1622  }
1623 
1624  // Emit delayed shadowing warnings now that the full capture list is known.
1625  DiagnoseShadowingLambdaDecls(LSI);
1626 
1627  if (!CurContext->isDependentContext()) {
1628  switch (ExprEvalContexts.back().Context) {
1629  // C++11 [expr.prim.lambda]p2:
1630  // A lambda-expression shall not appear in an unevaluated operand
1631  // (Clause 5).
1632  case ExpressionEvaluationContext::Unevaluated:
1633  case ExpressionEvaluationContext::UnevaluatedList:
1634  case ExpressionEvaluationContext::UnevaluatedAbstract:
1635  // C++1y [expr.const]p2:
1636  // A conditional-expression e is a core constant expression unless the
1637  // evaluation of e, following the rules of the abstract machine, would
1638  // evaluate [...] a lambda-expression.
1639  //
1640  // This is technically incorrect, there are some constant evaluated contexts
1641  // where this should be allowed. We should probably fix this when DR1607 is
1642  // ratified, it lays out the exact set of conditions where we shouldn't
1643  // allow a lambda-expression.
1644  case ExpressionEvaluationContext::ConstantEvaluated:
1645  // We don't actually diagnose this case immediately, because we
1646  // could be within a context where we might find out later that
1647  // the expression is potentially evaluated (e.g., for typeid).
1648  ExprEvalContexts.back().Lambdas.push_back(Lambda);
1649  break;
1650 
1651  case ExpressionEvaluationContext::DiscardedStatement:
1652  case ExpressionEvaluationContext::PotentiallyEvaluated:
1653  case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
1654  break;
1655  }
1656  }
1657 
1658  return MaybeBindToTemporary(Lambda);
1659 }
1660 
1662  SourceLocation ConvLocation,
1663  CXXConversionDecl *Conv,
1664  Expr *Src) {
1665  // Make sure that the lambda call operator is marked used.
1666  CXXRecordDecl *Lambda = Conv->getParent();
1667  CXXMethodDecl *CallOperator
1668  = cast<CXXMethodDecl>(
1669  Lambda->lookup(
1670  Context.DeclarationNames.getCXXOperatorName(OO_Call)).front());
1671  CallOperator->setReferenced();
1672  CallOperator->markUsed(Context);
1673 
1674  ExprResult Init = PerformCopyInitialization(
1676  /*NRVO=*/false),
1677  CurrentLocation, Src);
1678  if (!Init.isInvalid())
1679  Init = ActOnFinishFullExpr(Init.get());
1680 
1681  if (Init.isInvalid())
1682  return ExprError();
1683 
1684  // Create the new block to be returned.
1685  BlockDecl *Block = BlockDecl::Create(Context, CurContext, ConvLocation);
1686 
1687  // Set the type information.
1688  Block->setSignatureAsWritten(CallOperator->getTypeSourceInfo());
1689  Block->setIsVariadic(CallOperator->isVariadic());
1690  Block->setBlockMissingReturnType(false);
1691 
1692  // Add parameters.
1693  SmallVector<ParmVarDecl *, 4> BlockParams;
1694  for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I) {
1695  ParmVarDecl *From = CallOperator->getParamDecl(I);
1696  BlockParams.push_back(ParmVarDecl::Create(Context, Block,
1697  From->getLocStart(),
1698  From->getLocation(),
1699  From->getIdentifier(),
1700  From->getType(),
1701  From->getTypeSourceInfo(),
1702  From->getStorageClass(),
1703  /*DefaultArg=*/nullptr));
1704  }
1705  Block->setParams(BlockParams);
1706 
1707  Block->setIsConversionFromLambda(true);
1708 
1709  // Add capture. The capture uses a fake variable, which doesn't correspond
1710  // to any actual memory location. However, the initializer copy-initializes
1711  // the lambda object.
1712  TypeSourceInfo *CapVarTSI =
1713  Context.getTrivialTypeSourceInfo(Src->getType());
1714  VarDecl *CapVar = VarDecl::Create(Context, Block, ConvLocation,
1715  ConvLocation, nullptr,
1716  Src->getType(), CapVarTSI,
1717  SC_None);
1718  BlockDecl::Capture Capture(/*Variable=*/CapVar, /*ByRef=*/false,
1719  /*Nested=*/false, /*Copy=*/Init.get());
1720  Block->setCaptures(Context, Capture, /*CapturesCXXThis=*/false);
1721 
1722  // Add a fake function body to the block. IR generation is responsible
1723  // for filling in the actual body, which cannot be expressed as an AST.
1724  Block->setBody(new (Context) CompoundStmt(ConvLocation));
1725 
1726  // Create the block literal expression.
1727  Expr *BuildBlock = new (Context) BlockExpr(Block, Conv->getConversionType());
1728  ExprCleanupObjects.push_back(Block);
1729  Cleanup.setExprNeedsCleanups(true);
1730 
1731  return BuildBlock;
1732 }
void setImplicit(bool I=true)
Definition: DeclBase.h:552
FunctionDecl - An instance of this class is created to represent a function declaration or definition...
Definition: Decl.h:1698
SourceRange IntroducerRange
Source range covering the lambda introducer [...].
Definition: ScopeInfo.h:748
DeclaratorChunk::FunctionTypeInfo & getFunctionTypeInfo()
getFunctionTypeInfo - Retrieves the function type info object (looking through parentheses).
Definition: DeclSpec.h:2232
static DiagnosticBuilder Diag(DiagnosticsEngine *Diags, const LangOptions &Features, FullSourceLoc TokLoc, const char *TokBegin, const char *TokRangeBegin, const char *TokRangeEnd, unsigned DiagID)
Produce a diagnostic highlighting some portion of a literal.
A class which contains all the information about a particular captured value.
Definition: Decl.h:3693
unsigned getRawEncoding() const
When a SourceLocation itself cannot be used, this returns an (opaque) 32-bit integer encoding for it...
A (possibly-)qualified type.
Definition: Type.h:653
bool ExplicitParams
Whether the (empty) parameter list is explicit.
Definition: ScopeInfo.h:762
TemplateParameterList * GLTemplateParameterList
If this is a generic lambda, and the template parameter list has been created (from the AutoTemplateP...
Definition: ScopeInfo.h:784
VarDecl * createLambdaInitCaptureVarDecl(SourceLocation Loc, QualType InitCaptureType, IdentifierInfo *Id, unsigned InitStyle, Expr *Init)
Create a dummy variable within the declcontext of the lambda&#39;s call operator, for name lookup purpose...
Definition: SemaLambda.cpp:789
Stmt - This represents one statement.
Definition: Stmt.h:66
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:456
EnumConstantDecl - An instance of this object exists for each enum constant that is defined...
Definition: Decl.h:2665
QualType ReturnType
ReturnType - The target type of return statements in this context, or null if unknown.
Definition: ScopeInfo.h:609
StorageClass getStorageClass() const
Returns the storage class as written in the source.
Definition: Decl.h:1010
bool isConstexpr() const
Whether this is a (C++11) constexpr function or constexpr constructor.
Definition: Decl.h:2039
DeclarationName getCXXConversionFunctionName(CanQualType Ty)
getCXXConversionFunctionName - Returns the name of a C++ conversion function for the given Type...
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:86
bool isVariadic() const
Definition: Type.h:3617
LambdaCaptureDefault
The default, if any, capture method for a lambda expression.
Definition: Lambda.h:23
CanQualType getCanonicalFunctionResultType(QualType ResultType) const
Adjust the given function result type.
StringRef P
ExprResult BuildBlockForLambdaConversion(SourceLocation CurrentLocation, SourceLocation ConvLocation, CXXConversionDecl *Conv, Expr *Src)
static InitializationKind CreateDirect(SourceLocation InitLoc, SourceLocation LParenLoc, SourceLocation RParenLoc)
Create a direct initialization.
QualType getBlockPointerType(QualType T) const
Return the uniqued reference to the type for a block of the specified type.
The base class of the type hierarchy.
Definition: Type.h:1353
void setParams(ArrayRef< ParmVarDecl *> NewParamInfo)
Definition: Decl.cpp:4048
bool isFunctionDeclarator(unsigned &idx) const
isFunctionDeclarator - This method returns true if the declarator is a function declarator (looking t...
Definition: DeclSpec.h:2201
A container of type source information.
Definition: Decl.h:86
SourceLocation getLocStart() const LLVM_READONLY
Definition: Stmt.h:1443
QualType getConversionType() const
Returns the type that this conversion function is converting to.
Definition: DeclCXX.h:2717
void setInitStyle(InitializationStyle Style)
Definition: Decl.h:1258
Describes the capture of a variable or of this, or of a C++1y init-capture.
Definition: LambdaCapture.h:26
This file provides some common utility functions for processing Lambda related AST Constructs...
VarDecl - An instance of this class is created to represent a variable declaration or definition...
Definition: Decl.h:807
static CXXConversionDecl * Create(ASTContext &C, CXXRecordDecl *RD, SourceLocation StartLoc, const DeclarationNameInfo &NameInfo, QualType T, TypeSourceInfo *TInfo, bool isInline, bool isExplicit, bool isConstexpr, SourceLocation EndLocation)
Definition: DeclCXX.cpp:2231
Information about one declarator, including the parsed type information and the identifier.
Definition: DeclSpec.h:1720
QualType getReturnType() const
Definition: Decl.h:2205
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6307
Extra information about a function prototype.
Definition: Type.h:3389
bool isAmbiguous() const
Definition: Lookup.h:304
bool isInvalidDecl() const
Definition: DeclBase.h:546
Stores a list of template parameters for a TemplateDecl and its derived classes.
Definition: DeclTemplate.h:68
MangleNumberingContext & getMangleNumberingContext(ASTContext &Ctx)
Retrieve the mangling numbering context, used to consistently number constructs like lambdas for mang...
Definition: SemaLambda.cpp:367
static InitializationKind CreateDirectList(SourceLocation InitLoc)
bool isParameterPack() const
Whether this declaration is a parameter pack.
Definition: DeclBase.cpp:213
bool tryCaptureVariable(VarDecl *Var, SourceLocation Loc, TryCaptureKind Kind, SourceLocation EllipsisLoc, bool BuildAndDiagnose, QualType &CaptureType, QualType &DeclRefType, const unsigned *const FunctionScopeIndexToStopAt)
Try to capture the given variable.
Definition: SemaExpr.cpp:14508
Represents an expression – generally a full-expression – that introduces cleanups to be run at the ...
Definition: ExprCXX.h:3000
ParmVarDecl - Represents a parameter to a function.
Definition: Decl.h:1514
CXXRecordDecl * createLambdaClosureType(SourceRange IntroducerRange, TypeSourceInfo *Info, bool KnownDependent, LambdaCaptureDefault CaptureDefault)
Create a new lambda closure type.
Definition: SemaLambda.cpp:246
Defines the clang::Expr interface and subclasses for C++ expressions.
tok::TokenKind ContextKind
bool FTIHasNonVoidParameters(const DeclaratorChunk::FunctionTypeInfo &FTI)
Definition: SemaInternal.h:37
IdentifierInfo * getIdentifier() const
getIdentifier - Get the identifier that names this declaration, if there is one.
Definition: Decl.h:265
Scope * getTemplateParamParent()
Definition: Scope.h:259
FunctionType::ExtInfo ExtInfo
Definition: Type.h:3390
One of these records is kept for each identifier that is lexed.
bool isConst() const
Definition: DeclCXX.h:2006
sema::LambdaScopeInfo * getCurGenericLambda()
Retrieve the current generic lambda info, if any.
Definition: Sema.cpp:1452
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:149
ArrayRef< QualType > getParamTypes() const
Definition: Type.h:3498
field_range fields() const
Definition: Decl.h:3613
TypeSourceInfo * getTypeSourceInfo(ASTContext &Context, QualType T)
Creates a TypeSourceInfo for the given type.
std::unique_ptr< MangleNumberingContext > createMangleNumberingContext() const
LambdaCaptureKind
The different capture forms in a lambda introducer.
Definition: Lambda.h:34
FieldDecl - An instance of this class is created by Sema::ActOnField to represent a member of a struc...
Definition: Decl.h:2461
void setBlockMissingReturnType(bool val)
Definition: Decl.h:3822
unsigned TypeQuals
The type qualifiers: const/volatile/restrict/__unaligned The qualifier bitmask values are the same as...
Definition: DeclSpec.h:1243
const Expr * getRetValue() const
Definition: Stmt.cpp:925
bool isReferenceType() const
Definition: Type.h:5956
bool Equals(const DeclContext *DC) const
Determine whether this declaration context is equivalent to the declaration context DC...
Definition: DeclBase.h:1451
void setParams(ArrayRef< ParmVarDecl *> NewParamInfo)
Definition: Decl.h:2195
static CXXRecordDecl * CreateLambda(const ASTContext &C, DeclContext *DC, TypeSourceInfo *Info, SourceLocation Loc, bool DependentLambda, bool IsGeneric, LambdaCaptureDefault CaptureDefault)
Definition: DeclCXX.cpp:138
bool ContainsUnexpandedParameterPack
Whether the lambda contains an unexpanded parameter pack.
Definition: ScopeInfo.h:768
static ExprResult performLambdaVarCaptureInitialization(Sema &S, const LambdaScopeInfo::Capture &Capture, FieldDecl *Field)
IdentifierTable & Idents
Definition: ASTContext.h:537
An r-value expression (a pr-value in the C++11 taxonomy) produces a temporary value.
Definition: Specifiers.h:107
ArrayRef< ParmVarDecl * > parameters() const
Definition: Decl.h:2164
DeclClass * getAsSingle() const
Definition: Lookup.h:510
void setNameLoc(SourceLocation Loc)
Definition: TypeLoc.h:522
Represents the results of name lookup.
Definition: Lookup.h:32
PtrTy get() const
Definition: Ownership.h:162
Stmt * getBody(const FunctionDecl *&Definition) const
getBody - Retrieve the body (definition) of the function.
Definition: Decl.cpp:2612
RAII class used to indicate that we are performing provisional semantic analysis to determine the val...
Definition: Sema.h:7466
< Capturing the *this object by copy
Definition: Lambda.h:37
static LambdaCaptureDefault mapImplicitCaptureStyle(CapturingScopeInfo::ImplicitCaptureStyle ICS)
void addLambdaParameters(CXXMethodDecl *CallOperator, Scope *CurScope)
Introduce the lambda parameters into scope.
Definition: SemaLambda.cpp:496
static InitializedEntity InitializeLambdaToBlock(SourceLocation BlockVarLoc, QualType Type, bool NRVO)
Keeps track of the mangled names of lambda expressions and block literals within a particular context...
FunctionTemplateDecl * getDescribedFunctionTemplate() const
Retrieves the function template that is described by this function declaration.
Definition: Decl.cpp:3222
bool CheckCXXThisCapture(SourceLocation Loc, bool Explicit=false, bool BuildAndDiagnose=true, const unsigned *const FunctionScopeIndexToStopAt=nullptr, bool ByCopy=false)
Make sure the value of &#39;this&#39; is actually available in the current context, if it is a potentially ev...
unsigned getNumTypeObjects() const
Return the number of types applied to this declarator.
Definition: DeclSpec.h:2139
bool containsUnexpandedParameterPack() const
Whether this type is or contains an unexpanded parameter pack, used to support C++0x variadic templat...
Definition: Type.h:1635
A builtin binary operation expression such as "x + y" or "x <= y".
Definition: Expr.h:2985
bool isVolatileQualified() const
Determine whether this type is volatile-qualified.
Definition: Type.h:5790
void setLambdaMangling(unsigned ManglingNumber, Decl *ContextDecl)
Set the mangling number and context declaration for a lambda class.
Definition: DeclCXX.h:1845
CXXMethodDecl * startLambdaDefinition(CXXRecordDecl *Class, SourceRange IntroducerRange, TypeSourceInfo *MethodType, SourceLocation EndLoc, ArrayRef< ParmVarDecl *> Params, bool IsConstexprSpecified)
Start the definition of a lambda expression.
Definition: SemaLambda.cpp:375
void finishedExplicitCaptures()
Note when all explicit captures have been added.
Definition: ScopeInfo.h:829
DeclContext * getLambdaAwareParentOfDeclContext(DeclContext *DC)
Definition: ASTLambda.h:71
Scope - A scope is a transient data structure that is used while parsing the program.
Definition: Scope.h:39
ExprResult Perform(Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind, MultiExprArg Args, QualType *ResultType=nullptr)
Perform the actual initialization of the given entity based on the computed initialization sequence...
Definition: SemaInit.cpp:6530
field_iterator field_begin() const
Definition: Decl.cpp:3937
static EnumDecl * findCommonEnumForBlockReturns(ArrayRef< ReturnStmt *> returns)
Attempt to find a common type T for which all of the returned expressions in a block are enumerator-l...
Definition: SemaLambda.cpp:590
bool hasNameForLinkage() const
Is this tag type named, either directly or via being defined in a typedef of this type...
Definition: Decl.h:3177
Represents a C++ nested-name-specifier or a global scope specifier.
Definition: DeclSpec.h:63
A C++ lambda expression, which produces a function object (of unspecified type) that can be invoked l...
Definition: ExprCXX.h:1580
static VarDecl * Create(ASTContext &C, DeclContext *DC, SourceLocation StartLoc, SourceLocation IdLoc, IdentifierInfo *Id, QualType T, TypeSourceInfo *TInfo, StorageClass S)
Definition: Decl.cpp:1865
const LangOptions & getLangOpts() const
Definition: Sema.h:1193
bool isLambdaCallOperator(const CXXMethodDecl *MD)
Definition: ASTLambda.h:28
static FunctionTemplateDecl * Create(ASTContext &C, DeclContext *DC, SourceLocation L, DeclarationName Name, TemplateParameterList *Params, NamedDecl *Decl)
Create a function template node.
StringRef getLambdaStaticInvokerName()
Definition: ASTLambda.h:23
ExprResult BuildDeclarationNameExpr(const CXXScopeSpec &SS, LookupResult &R, bool NeedsADL, bool AcceptInvalidDecl=false)
Definition: SemaExpr.cpp:2719
static void addFunctionPointerConversion(Sema &S, SourceRange IntroducerRange, CXXRecordDecl *Class, CXXMethodDecl *CallOperator)
Add a lambda&#39;s conversion to function pointer, as described in C++11 [expr.prim.lambda]p6.
SmallVector< TemplateTypeParmDecl *, 4 > AutoTemplateParams
Store the list of the auto parameters for a generic lambda.
Definition: ScopeInfo.h:779
TypeSpecTypeLoc pushTypeSpec(QualType T)
Pushes space for a typespec TypeLoc.
CleanupInfo Cleanup
Whether any of the capture expressions requires cleanups.
Definition: ScopeInfo.h:765
TyLocType push(QualType T)
Pushes space for a new TypeLoc of the given type.
lookup_result lookup(DeclarationName Name) const
lookup - Find the declarations (if any) with the given Name in this context.
Definition: DeclBase.cpp:1521
bool CaptureHasSideEffects(const sema::LambdaScopeInfo::Capture &From)
Does copying/destroying the captured variable have side effects?
ExtInfo withCallingConv(CallingConv cc) const
Definition: Type.h:3179
ImplicitCaptureStyle ImpCaptureStyle
Definition: ScopeInfo.h:467
bool isIntegralOrUnscopedEnumerationType() const
Determine whether this type is an integral or unscoped enumeration type.
Definition: Type.cpp:1735
ConditionalOperator - The ?: ternary operator.
Definition: Expr.h:3269
Sema - This implements semantic analysis and AST building for C.
Definition: Sema.h:274
CompoundStmt - This represents a group of statements like { stmt stmt }.
Definition: Stmt.h:595
bool Mutable
Whether this is a mutable lambda.
Definition: ScopeInfo.h:759
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1590
SmallVector< ReturnStmt *, 4 > Returns
The list of return statements that occur within the function or block, if there is any chance of appl...
Definition: ScopeInfo.h:170
Represents a prototype with parameter type info, e.g.
Definition: Type.h:3270
SourceLocation getLocEnd() const LLVM_READONLY
Definition: Stmt.cpp:290
static ImplicitCastExpr * Create(const ASTContext &Context, QualType T, CastKind Kind, Expr *Operand, const CXXCastPath *BasePath, ExprValueKind Cat)
Definition: Expr.cpp:1718
DeclarationNameTable DeclarationNames
Definition: ASTContext.h:540
void finishLambdaExplicitCaptures(sema::LambdaScopeInfo *LSI)
Note that we have finished the explicit captures for the given lambda.
Definition: SemaLambda.cpp:492
SmallVector< LambdaCapture, 4 > Captures
Definition: DeclSpec.h:2529
SourceLocation PotentialThisCaptureLocation
Definition: ScopeInfo.h:817
unsigned NumExplicitCaptures
The number of captures in the Captures list that are explicit captures.
Definition: ScopeInfo.h:756
TypeSourceInfo * getTrivialTypeSourceInfo(QualType T, SourceLocation Loc=SourceLocation()) const
Allocate a TypeSourceInfo where all locations have been initialized to a given location, which defaults to the empty location.
bool HasSideEffects(const ASTContext &Ctx, bool IncludePossibleEffects=true) const
HasSideEffects - This routine returns true for all those expressions which have any effect other than...
Definition: Expr.cpp:2940
TemplateParameterList * getTemplateParameters() const
Get the list of template parameters.
Definition: DeclTemplate.h:432
DeclContext * getLexicalParent()
getLexicalParent - Returns the containing lexical DeclContext.
Definition: DeclBase.h:1347
CXXMethodDecl * CallOperator
The lambda&#39;s compiler-generated operator().
Definition: ScopeInfo.h:745
BlockDecl - This represents a block literal declaration, which is like an unnamed FunctionDecl...
Definition: Decl.h:3689
ExprResult ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body, Scope *CurScope)
ActOnLambdaExpr - This is called when the body of a lambda expression was successfully completed...
Expr - This represents one expression.
Definition: Expr.h:106
bool isVariadic() const
Whether this function is variadic.
Definition: Decl.cpp:2570
int Id
Definition: ASTDiff.cpp:191
bool hasLocalStorage() const
hasLocalStorage - Returns true if a variable with function scope is a non-static local variable...
Definition: Decl.h:1026
QualType buildLambdaInitCaptureInitialization(SourceLocation Loc, bool ByRef, IdentifierInfo *Id, bool DirectInit, Expr *&Init)
Definition: SemaLambda.cpp:726
const FunctionProtoType * T
This file defines the classes used to store parsed information about declaration-specifiers and decla...
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6370
BlockExpr - Adaptor class for mixing a BlockDecl with expressions.
Definition: Expr.h:4851
T getAs() const
Convert to the specified TypeLoc type, returning a null TypeLoc if this TypeLoc is not of the desired...
Definition: TypeLoc.h:86
void setInit(Expr *I)
Definition: Decl.cpp:2152
void setInvalidDecl(bool Invalid=true)
setInvalidDecl - Indicates the Decl had a semantic error.
Definition: DeclBase.cpp:132
void setRetValue(Expr *E)
Definition: Stmt.h:1430
bool isFileContext() const
Definition: DeclBase.h:1397
DeclContext * getDeclContext()
Definition: DeclBase.h:425
bool isConstexprSpecified() const
Definition: DeclSpec.h:703
static TemplateParameterList * getGenericLambdaTemplateParameterList(LambdaScopeInfo *LSI, Sema &SemaRef)
Definition: SemaLambda.cpp:228
void buildLambdaScope(sema::LambdaScopeInfo *LSI, CXXMethodDecl *CallOperator, SourceRange IntroducerRange, LambdaCaptureDefault CaptureDefault, SourceLocation CaptureDefaultLoc, bool ExplicitParams, bool ExplicitResultType, bool Mutable)
Endow the lambda scope info with the relevant properties.
Definition: SemaLambda.cpp:457
bool isCaptured(VarDecl *Var) const
Determine whether the given variable has been captured.
Definition: ScopeInfo.h:642
QualType getType() const
Definition: Expr.h:128
bool isFunctionOrMethod() const
Definition: DeclBase.h:1380
Capture & getCapture(VarDecl *Var)
Retrieve the capture of the given variable, if it has been captured already.
Definition: ScopeInfo.h:651
Direct list-initialization (C++11)
Definition: Decl.h:818
static LambdaExpr * Create(const ASTContext &C, CXXRecordDecl *Class, SourceRange IntroducerRange, LambdaCaptureDefault CaptureDefault, SourceLocation CaptureDefaultLoc, ArrayRef< LambdaCapture > Captures, bool ExplicitParams, bool ExplicitResultType, ArrayRef< Expr *> CaptureInits, SourceLocation ClosingBrace, bool ContainsUnexpandedParameterPack)
Construct a new lambda expression.
Definition: ExprCXX.cpp:931
static bool isInInlineFunction(const DeclContext *DC)
Determine whether the given context is or is enclosed in an inline function.
Definition: SemaLambda.cpp:268
DeclContext * getParent()
getParent - Returns the containing DeclContext.
Definition: DeclBase.h:1331
ReturnStmt - This represents a return, optionally of an expression: return; return 4;...
Definition: Stmt.h:1413
bool isInvalid() const
Definition: Ownership.h:158
SourceLocation getEnd() const
QualType getFunctionType(QualType ResultTy, ArrayRef< QualType > Args, const FunctionProtoType::ExtProtoInfo &EPI) const
Return a normal function type with a typed argument list.
Definition: ASTContext.h:1333
struct CXXOpName CXXOperatorName
bool isDependentContext() const
Determines whether this context is dependent on a template parameter.
Definition: DeclBase.cpp:1026
Common base class for placeholders for types that get replaced by placeholder type deduction: C++11 a...
Definition: Type.h:4363
const Type * getBaseElementTypeUnsafe() const
Get the base element type of this type, potentially discarding type qualifiers.
Definition: Type.h:6265
Represents a C++ conversion function within a class.
Definition: DeclCXX.h:2682
QualType getTypeDeclType(const TypeDecl *Decl, const TypeDecl *PrevDecl=nullptr) const
Return the unique reference to the type for the specified type declaration.
Definition: ASTContext.h:1347
bool isNull() const
Return true if this QualType doesn&#39;t point to a type yet.
Definition: Type.h:719
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:233
TypeLoc getReturnLoc() const
Definition: TypeLoc.h:1480
static TemplateParameterList * Create(const ASTContext &C, SourceLocation TemplateLoc, SourceLocation LAngleLoc, ArrayRef< NamedDecl *> Params, SourceLocation RAngleLoc, Expr *RequiresClause)
static InitializationKind CreateCopy(SourceLocation InitLoc, SourceLocation EqualLoc, bool AllowExplicitConvs=false)
Create a copy initialization.
FieldDecl * buildInitCaptureField(sema::LambdaScopeInfo *LSI, VarDecl *Var)
Build the implicit field for an init-capture.
Definition: SemaLambda.cpp:810
void setIsVariadic(bool value)
Definition: Decl.h:3764
ExprResult BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc, sema::LambdaScopeInfo *LSI)
Complete a lambda-expression having processed and attached the lambda body.
SourceLocation DefaultLoc
Definition: DeclSpec.h:2527
Kind
ActionResult - This structure is used while parsing/acting on expressions, stmts, etc...
Definition: Ownership.h:144
void setIsConversionFromLambda(bool val)
Definition: Decl.h:3825
ExtProtoInfo getExtProtoInfo() const
Definition: Type.h:3502
unsigned getNumExprs() const
Definition: Expr.h:4618
SourceLocation getLocation() const
Retrieve the location at which this variable was captured.
Definition: ScopeInfo.h:568
Encodes a location in the source.
IdentifierInfo & get(StringRef Name)
Return the identifier token info for the specified named identifier.
QualType getReturnType() const
Definition: Type.h:3203
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of enums...
Definition: Type.h:4004
static InitializedEntity InitializeLambdaCapture(IdentifierInfo *VarID, QualType FieldType, SourceLocation Loc)
Create the initialization entity for a lambda capture.
void DiagnoseUnusedLambdaCapture(const sema::LambdaScopeInfo::Capture &From)
Diagnose if an explicit lambda capture is unused.
CXXRecordDecl * Lambda
The class that describes the lambda.
Definition: ScopeInfo.h:742
static Optional< unsigned > getStackIndexOfNearestEnclosingCaptureReadyLambda(ArrayRef< const clang::sema::FunctionScopeInfo *> FunctionScopes, VarDecl *VarToCapture)
Examines the FunctionScopeInfo stack to determine the nearest enclosing lambda (to the current lambda...
Definition: SemaLambda.cpp:63
void setReferenced(bool R=true)
Definition: DeclBase.h:581
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:1964
No ref-qualifier was provided.
Definition: Type.h:1306
C-style initialization with assignment.
Definition: Decl.h:812
const ParmVarDecl * getParamDecl(unsigned i) const
Definition: Decl.h:2187
CanQualType VoidTy
Definition: ASTContext.h:996
bool isGenericLambda() const
Determine whether this class describes a generic lambda function object (i.e.
Definition: DeclCXX.cpp:1116
Describes the kind of initialization being performed, along with location information for tokens rela...
SmallVector< Capture, 4 > Captures
Captures - The captures.
Definition: ScopeInfo.h:601
ImplicitCastExpr - Allows us to explicitly represent implicit type conversions, which have no direct ...
Definition: Expr.h:2822
MangleNumberingContext * getCurrentMangleNumberContext(const DeclContext *DC, Decl *&ManglingContextDecl)
Compute the mangling number context for a lambda expression or block literal.
Definition: SemaLambda.cpp:281
SourceLocation CaptureDefaultLoc
Source location of the &#39;&&#39; or &#39;=&#39; specifying the default capture type, if any.
Definition: ScopeInfo.h:752
Expr ** getExprs()
Definition: Expr.h:4630
StmtExpr - This is the GNU Statement Expression extension: ({int X=4; X;}).
Definition: Expr.h:3488
MutableArrayRef< Expr * > MultiExprArg
Definition: Ownership.h:261
static EnumDecl * findEnumForBlockReturn(Expr *E)
If this expression is an enumerator-like expression of some type T, return the type T; otherwise...
Definition: SemaLambda.cpp:518
DeclarationNameLoc - Additional source/type location info for a declaration name. ...
SourceRange getSourceRange() const LLVM_READONLY
Get the source range that spans this declarator.
Definition: DeclSpec.h:1871
CallingConv getDefaultCallingConvention(bool IsVariadic, bool IsCXXMethod) const
Retrieves the default calling convention for the current target.
This file provides some common utility functions for processing Lambdas.
static ParmVarDecl * Create(ASTContext &C, DeclContext *DC, SourceLocation StartLoc, SourceLocation IdLoc, IdentifierInfo *Id, QualType T, TypeSourceInfo *TInfo, StorageClass S, Expr *DefArg)
Definition: Decl.cpp:2451
Dataflow Directional Tag Classes.
void ActOnLambdaError(SourceLocation StartLoc, Scope *CurScope, bool IsInstantiation=false)
ActOnLambdaError - If there is an error parsing a lambda, this callback is invoked to pop the informa...
void setBody(CompoundStmt *B)
Definition: Decl.h:3768
LambdaCaptureDefault Default
Definition: DeclSpec.h:2528
DeclContext - This is used only as base class of specific decl types that can act as declaration cont...
Definition: DeclBase.h:1252
void deduceClosureReturnType(sema::CapturingScopeInfo &CSI)
Deduce a block or lambda&#39;s return type based on the return statements present in the body...
Definition: SemaLambda.cpp:637
bool isRecord() const
Definition: DeclBase.h:1405
Optional< unsigned > getStackIndexOfNearestEnclosingCaptureCapableLambda(ArrayRef< const sema::FunctionScopeInfo *> FunctionScopes, VarDecl *VarToCapture, Sema &S)
Examines the FunctionScopeInfo stack to determine the nearest enclosing lambda (to the current lambda...
Definition: SemaLambda.cpp:173
static FixItHint CreateRemoval(CharSourceRange RemoveRange)
Create a code modification hint that removes the given source range.
Definition: Diagnostic.h:116
const Expr * getInit() const
Definition: Decl.h:1213
static void addBlockPointerConversion(Sema &S, SourceRange IntroducerRange, CXXRecordDecl *Class, CXXMethodDecl *CallOperator)
Add a lambda&#39;s conversion to block pointer.
DeclarationName - The name of a declaration.
const CXXRecordDecl * getParent() const
Returns the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2085
MangleNumberingContext & getManglingNumberContext(const DeclContext *DC)
Retrieve the context for computing mangling numbers in the given DeclContext.
SourceLocation getLocStart() const LLVM_READONLY
Definition: Decl.h:732
EnumDecl - Represents an enum.
Definition: Decl.h:3233
DeclarationNameInfo - A collector data type for bundling together a DeclarationName and the correspnd...
bool isUndeducedType() const
Determine whether this type is an undeduced type, meaning that it somehow involves a C++11 &#39;auto&#39; typ...
Definition: Type.h:6240
void setInitCapture(bool IC)
Definition: Decl.h:1379
Capturing variable-length array type.
Definition: Lambda.h:39
void ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro, Declarator &ParamInfo, Scope *CurScope)
ActOnStartOfLambdaDefinition - This is called just before we start parsing the body of a lambda; it a...
Definition: SemaLambda.cpp:825
CanQualType DependentTy
Definition: ASTContext.h:1013
TypeSourceInfo * getTypeSourceInfo() const
Definition: Decl.h:708
bool hasSameType(QualType T1, QualType T2) const
Determine whether the given types T1 and T2 are equivalent.
Definition: ASTContext.h:2190
Simple template class for restricting typo correction candidates to ones having a single Decl* of the...
QualType getAutoDeductType() const
C++11 deduction pattern for &#39;auto&#39; type.
static CXXMethodDecl * Create(ASTContext &C, CXXRecordDecl *RD, SourceLocation StartLoc, const DeclarationNameInfo &NameInfo, QualType T, TypeSourceInfo *TInfo, StorageClass SC, bool isInline, bool isConstexpr, SourceLocation EndLocation)
Definition: DeclCXX.cpp:1698
void addDecl(Decl *D)
Add the declaration D into this context.
Definition: DeclBase.cpp:1410
Capturing the *this object by reference.
Definition: Lambda.h:35
void markUsed(ASTContext &C)
Mark the declaration used, in the sense of odr-use.
Definition: DeclBase.cpp:401
Capture & getCXXThisCapture()
Retrieve the capture of C++ &#39;this&#39;, if it has been captured.
Definition: ScopeInfo.h:636
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
Definition: ASTContext.h:2174
void setSignatureAsWritten(TypeSourceInfo *Sig)
Definition: Decl.h:3770
TypeLoc getTypeLoc() const
Return the TypeLoc wrapper for the type source info.
Definition: TypeLoc.h:239
static BlockDecl * Create(ASTContext &C, DeclContext *DC, SourceLocation L)
Definition: Decl.cpp:4225
Call-style initialization (C++98)
Definition: Decl.h:815
TranslationUnitDecl * getTranslationUnitDecl() const
Definition: ASTContext.h:989
Describes the sequence of initializations required to initialize a given object or reference with a s...
Represents a C++ struct/union/class.
Definition: DeclCXX.h:299
bool isVoidType() const
Definition: Type.h:6171
void setConstexpr(bool IC)
Definition: Decl.h:2040
Capturing by reference.
Definition: Lambda.h:38
TryCaptureKind
Definition: Sema.h:4010
const DeclSpec & getDeclSpec() const
getDeclSpec - Return the declaration-specifier that this declarator was declared with.
Definition: DeclSpec.h:1836
bool isCXXThisCaptured() const
Determine whether the C++ &#39;this&#39; is captured.
Definition: ScopeInfo.h:633
QualType getPointerType(QualType T) const
Return the uniqued reference to the type for a pointer to the specified type.
Defines the clang::TargetInfo interface.
Represents a complete lambda introducer.
Definition: DeclSpec.h:2508
bool HasImplicitReturnType
Whether the target type of return statements in this context is deduced (e.g.
Definition: ScopeInfo.h:605
ExprResult ExprError()
Definition: Ownership.h:267
void setDescribedFunctionTemplate(FunctionTemplateDecl *Template)
Definition: Decl.cpp:3226
bool isDependentType() const
Whether this type is a dependent type, meaning that its definition somehow depends on a template para...
Definition: Type.h:1860
A reference to a declared variable, function, enum, etc.
Definition: Expr.h:956
void addCapture(VarDecl *Var, bool isBlock, bool isByref, bool isNested, SourceLocation Loc, SourceLocation EllipsisLoc, QualType CaptureType, Expr *Cpy)
Definition: ScopeInfo.h:611
QualType getType() const
Definition: Decl.h:639
bool empty() const
Return true if no decls were found.
Definition: Lookup.h:342
void setCaptures(ASTContext &Context, ArrayRef< Capture > Captures, bool CapturesCXXThis)
Definition: Decl.cpp:4059
A trivial tuple used to represent a source range.
void setLexicalDeclContext(DeclContext *DC)
Definition: DeclBase.cpp:288
ASTContext & Context
Definition: Sema.h:316
NamedDecl - This represents a decl with a name.
Definition: Decl.h:245
bool isTranslationUnit() const
Definition: DeclBase.h:1401
void setAccess(AccessSpecifier AS)
Definition: DeclBase.h:455
Describes an entity that is being initialized.
static FieldDecl * Create(const ASTContext &C, DeclContext *DC, SourceLocation StartLoc, SourceLocation IdLoc, IdentifierInfo *Id, QualType T, TypeSourceInfo *TInfo, Expr *BW, bool Mutable, InClassInitStyle InitStyle)
Definition: Decl.cpp:3608
unsigned getNumParams() const
getNumParams - Return the number of parameters this function must have based on its FunctionType...
Definition: Decl.cpp:2906
SourceLocation getLocStart() const LLVM_READONLY
Definition: Stmt.cpp:277
Wrapper for source info for pointers.
Definition: TypeLoc.h:1271
SourceLocation getBegin() const
static void adjustBlockReturnsToEnum(Sema &S, ArrayRef< ReturnStmt *> returns, QualType returnType)
Adjust the given return statements so that they formally return the given type.
Definition: SemaLambda.cpp:611
No in-class initializer.
Definition: Specifiers.h:227
Declaration of a template function.
Definition: DeclTemplate.h:958
SourceLocation getLocation() const
Definition: DeclBase.h:416
QualType getType() const
Return the type wrapped by this type source info.
Definition: Decl.h:97
Expr * IgnoreParens() LLVM_READONLY
IgnoreParens - Ignore parentheses.
Definition: Expr.cpp:2432
DeclarationName getCXXOperatorName(OverloadedOperatorKind Op)
getCXXOperatorName - Get the name of the overloadable C++ operator corresponding to Op...