Coverage Report

Created: 2022-05-14 11:35

/Users/buildslave/jenkins/workspace/coverage/llvm-project/clang/lib/Sema/SemaLambda.cpp
Line
Count
Source (jump to first uncovered line)
1
//===--- SemaLambda.cpp - Semantic Analysis for C++11 Lambdas -------------===//
2
//
3
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4
// See https://llvm.org/LICENSE.txt for license information.
5
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6
//
7
//===----------------------------------------------------------------------===//
8
//
9
//  This file implements semantic analysis for C++ lambda expressions.
10
//
11
//===----------------------------------------------------------------------===//
12
#include "clang/Sema/DeclSpec.h"
13
#include "TypeLocBuilder.h"
14
#include "clang/AST/ASTLambda.h"
15
#include "clang/AST/ExprCXX.h"
16
#include "clang/Basic/TargetInfo.h"
17
#include "clang/Sema/Initialization.h"
18
#include "clang/Sema/Lookup.h"
19
#include "clang/Sema/Scope.h"
20
#include "clang/Sema/ScopeInfo.h"
21
#include "clang/Sema/SemaInternal.h"
22
#include "clang/Sema/SemaLambda.h"
23
#include "llvm/ADT/STLExtras.h"
24
using namespace clang;
25
using namespace sema;
26
27
/// Examines the FunctionScopeInfo stack to determine the nearest
28
/// enclosing lambda (to the current lambda) that is 'capture-ready' for
29
/// the variable referenced in the current lambda (i.e. \p VarToCapture).
30
/// If successful, returns the index into Sema's FunctionScopeInfo stack
31
/// of the capture-ready lambda's LambdaScopeInfo.
32
///
33
/// Climbs down the stack of lambdas (deepest nested lambda - i.e. current
34
/// lambda - is on top) to determine the index of the nearest enclosing/outer
35
/// lambda that is ready to capture the \p VarToCapture being referenced in
36
/// the current lambda.
37
/// As we climb down the stack, we want the index of the first such lambda -
38
/// that is the lambda with the highest index that is 'capture-ready'.
39
///
40
/// A lambda 'L' is capture-ready for 'V' (var or this) if:
41
///  - its enclosing context is non-dependent
42
///  - and if the chain of lambdas between L and the lambda in which
43
///    V is potentially used (i.e. the lambda at the top of the scope info
44
///    stack), can all capture or have already captured V.
45
/// If \p VarToCapture is 'null' then we are trying to capture 'this'.
46
///
47
/// Note that a lambda that is deemed 'capture-ready' still needs to be checked
48
/// for whether it is 'capture-capable' (see
49
/// getStackIndexOfNearestEnclosingCaptureCapableLambda), before it can truly
50
/// capture.
51
///
52
/// \param FunctionScopes - Sema's stack of nested FunctionScopeInfo's (which a
53
///  LambdaScopeInfo inherits from).  The current/deepest/innermost lambda
54
///  is at the top of the stack and has the highest index.
55
/// \param VarToCapture - the variable to capture.  If NULL, capture 'this'.
56
///
57
/// \returns An Optional<unsigned> Index that if evaluates to 'true' contains
58
/// the index (into Sema's FunctionScopeInfo stack) of the innermost lambda
59
/// which is capture-ready.  If the return value evaluates to 'false' then
60
/// no lambda is capture-ready for \p VarToCapture.
61
62
static inline Optional<unsigned>
63
getStackIndexOfNearestEnclosingCaptureReadyLambda(
64
    ArrayRef<const clang::sema::FunctionScopeInfo *> FunctionScopes,
65
1.01k
    VarDecl *VarToCapture) {
66
  // Label failure to capture.
67
1.01k
  const Optional<unsigned> NoLambdaIsCaptureReady;
68
69
  // Ignore all inner captured regions.
70
1.01k
  unsigned CurScopeIndex = FunctionScopes.size() - 1;
71
1.01k
  while (CurScopeIndex > 0 && isa<clang::sema::CapturedRegionScopeInfo>(
72
1.01k
                                  FunctionScopes[CurScopeIndex]))
73
5
    --CurScopeIndex;
74
1.01k
  assert(
75
1.01k
      isa<clang::sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]) &&
76
1.01k
      "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
0
  const bool IsCapturingThis = !VarToCapture;
80
1.01k
  const bool IsCapturingVariable = !IsCapturingThis;
81
82
  // Start with the current lambda at the top of the stack (highest index).
83
1.01k
  DeclContext *EnclosingDC =
84
1.01k
      cast<sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex])->CallOperator;
85
86
1.59k
  do {
87
1.59k
    const clang::sema::LambdaScopeInfo *LSI =
88
1.59k
        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
1.59k
    if (IsCapturingVariable &&
97
1.59k
        
VarToCapture->getDeclContext()->Equals(EnclosingDC)1.43k
)
98
219
      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.
116
1.37k
    if (LSI->ImpCaptureStyle == sema::LambdaScopeInfo::ImpCap_None) {
117
305
      if (IsCapturingVariable && 
!LSI->isCaptured(VarToCapture)253
)
118
173
        return NoLambdaIsCaptureReady;
119
132
      if (IsCapturingThis && 
!LSI->isCXXThisCaptured()52
)
120
48
        return NoLambdaIsCaptureReady;
121
132
    }
122
1.15k
    EnclosingDC = getLambdaAwareParentOfDeclContext(EnclosingDC);
123
124
1.15k
    assert(CurScopeIndex);
125
0
    --CurScopeIndex;
126
1.15k
  } while (!EnclosingDC->isTranslationUnit() &&
127
1.15k
           EnclosingDC->isDependentContext() &&
128
1.15k
           
isLambdaCallOperator(EnclosingDC)756
);
129
130
571
  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
571
  if (!EnclosingDC->isDependentContext())
134
401
    return CurScopeIndex + 1;
135
170
  return NoLambdaIsCaptureReady;
136
571
}
137
138
/// Examines the FunctionScopeInfo stack to determine the nearest
139
/// enclosing lambda (to the current lambda) that is 'capture-capable' for
140
/// the variable referenced in the current lambda (i.e. \p VarToCapture).
141
/// If successful, returns the index into Sema's FunctionScopeInfo stack
142
/// of the capture-capable lambda's LambdaScopeInfo.
143
///
144
/// Given the current stack of lambdas being processed by Sema and
145
/// the variable of interest, to identify the nearest enclosing lambda (to the
146
/// current lambda at the top of the stack) that can truly capture
147
/// a variable, it has to have the following two properties:
148
///  a) 'capture-ready' - be the innermost lambda that is 'capture-ready':
149
///     - climb down the stack (i.e. starting from the innermost and examining
150
///       each outer lambda step by step) checking if each enclosing
151
///       lambda can either implicitly or explicitly capture the variable.
152
///       Record the first such lambda that is enclosed in a non-dependent
153
///       context. If no such lambda currently exists return failure.
154
///  b) 'capture-capable' - make sure the 'capture-ready' lambda can truly
155
///  capture the variable by checking all its enclosing lambdas:
156
///     - check if all outer lambdas enclosing the 'capture-ready' lambda
157
///       identified above in 'a' can also capture the variable (this is done
158
///       via tryCaptureVariable for variables and CheckCXXThisCapture for
159
///       'this' by passing in the index of the Lambda identified in step 'a')
160
///
161
/// \param FunctionScopes - Sema's stack of nested FunctionScopeInfo's (which a
162
/// LambdaScopeInfo inherits from).  The current/deepest/innermost lambda
163
/// is at the top of the stack.
164
///
165
/// \param VarToCapture - the variable to capture.  If NULL, capture 'this'.
166
///
167
///
168
/// \returns An Optional<unsigned> Index that if evaluates to 'true' contains
169
/// the index (into Sema's FunctionScopeInfo stack) of the innermost lambda
170
/// which is capture-capable.  If the return value evaluates to 'false' then
171
/// no lambda is capture-capable for \p VarToCapture.
172
173
Optional<unsigned> clang::getStackIndexOfNearestEnclosingCaptureCapableLambda(
174
    ArrayRef<const sema::FunctionScopeInfo *> FunctionScopes,
175
1.01k
    VarDecl *VarToCapture, Sema &S) {
176
177
1.01k
  const Optional<unsigned> NoLambdaIsCaptureCapable;
178
179
1.01k
  const Optional<unsigned> OptionalStackIndex =
180
1.01k
      getStackIndexOfNearestEnclosingCaptureReadyLambda(FunctionScopes,
181
1.01k
                                                        VarToCapture);
182
1.01k
  if (!OptionalStackIndex)
183
610
    return NoLambdaIsCaptureCapable;
184
185
401
  const unsigned IndexOfCaptureReadyLambda = OptionalStackIndex.getValue();
186
401
  assert(((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) ||
187
401
          S.getCurGenericLambda()) &&
188
401
         "The capture ready lambda for a potential capture can only be the "
189
401
         "current lambda if it is a generic lambda");
190
191
0
  const sema::LambdaScopeInfo *const CaptureReadyLambdaLSI =
192
401
      cast<sema::LambdaScopeInfo>(FunctionScopes[IndexOfCaptureReadyLambda]);
193
194
  // If VarToCapture is null, we are attempting to capture 'this'
195
401
  const bool IsCapturingThis = !VarToCapture;
196
401
  const bool IsCapturingVariable = !IsCapturingThis;
197
198
401
  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
381
    QualType CaptureType, DeclRefType;
203
381
    const bool CanCaptureVariable =
204
381
        !S.tryCaptureVariable(VarToCapture,
205
381
                              /*ExprVarIsUsedInLoc*/ SourceLocation(),
206
381
                              clang::Sema::TryCapture_Implicit,
207
381
                              /*EllipsisLoc*/ SourceLocation(),
208
381
                              /*BuildAndDiagnose*/ false, CaptureType,
209
381
                              DeclRefType, &IndexOfCaptureReadyLambda);
210
381
    if (!CanCaptureVariable)
211
28
      return NoLambdaIsCaptureCapable;
212
381
  } 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
20
    const bool CanCaptureThis =
217
20
        !S.CheckCXXThisCapture(
218
20
             CaptureReadyLambdaLSI->PotentialThisCaptureLocation,
219
20
             /*Explicit*/ false, /*BuildAndDiagnose*/ false,
220
20
             &IndexOfCaptureReadyLambda);
221
20
    if (!CanCaptureThis)
222
4
      return NoLambdaIsCaptureCapable;
223
20
  }
224
369
  return IndexOfCaptureReadyLambda;
225
401
}
226
227
static inline TemplateParameterList *
228
21.7k
getGenericLambdaTemplateParameterList(LambdaScopeInfo *LSI, Sema &SemaRef) {
229
21.7k
  if (!LSI->GLTemplateParameterList && 
!LSI->TemplateParams.empty()16.7k
) {
230
2.21k
    LSI->GLTemplateParameterList = TemplateParameterList::Create(
231
2.21k
        SemaRef.Context,
232
2.21k
        /*Template kw loc*/ SourceLocation(),
233
2.21k
        /*L angle loc*/ LSI->ExplicitTemplateParamsRange.getBegin(),
234
2.21k
        LSI->TemplateParams,
235
2.21k
        /*R angle loc*/LSI->ExplicitTemplateParamsRange.getEnd(),
236
2.21k
        LSI->RequiresClause.get());
237
2.21k
  }
238
21.7k
  return LSI->GLTemplateParameterList;
239
21.7k
}
240
241
CXXRecordDecl *
242
Sema::createLambdaClosureType(SourceRange IntroducerRange, TypeSourceInfo *Info,
243
                              unsigned LambdaDependencyKind,
244
10.8k
                              LambdaCaptureDefault CaptureDefault) {
245
10.8k
  DeclContext *DC = CurContext;
246
10.9k
  while (!(DC->isFunctionOrMethod() || 
DC->isRecord()1.68k
||
DC->isFileContext()1.14k
))
247
18
    DC = DC->getParent();
248
10.8k
  bool IsGenericLambda = getGenericLambdaTemplateParameterList(getCurLambda(),
249
10.8k
                                                               *this);
250
  // Start constructing the lambda class.
251
10.8k
  CXXRecordDecl *Class = CXXRecordDecl::CreateLambda(
252
10.8k
      Context, DC, Info, IntroducerRange.getBegin(), LambdaDependencyKind,
253
10.8k
      IsGenericLambda, CaptureDefault);
254
10.8k
  DC->addDecl(Class);
255
256
10.8k
  return Class;
257
10.8k
}
258
259
/// Determine whether the given context is or is enclosed in an inline
260
/// function.
261
1.05M
static bool isInInlineFunction(const DeclContext *DC) {
262
1.50M
  while (!DC->isFileContext()) {
263
460k
    if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(DC))
264
25.8k
      if (FD->isInlined())
265
10.4k
        return true;
266
267
449k
    DC = DC->getLexicalParent();
268
449k
  }
269
270
1.04M
  return false;
271
1.05M
}
272
273
std::tuple<MangleNumberingContext *, Decl *>
274
1.07M
Sema::getCurrentMangleNumberContext(const DeclContext *DC) {
275
  // Compute the context for allocating mangling numbers in the current
276
  // expression, if the ABI requires them.
277
1.07M
  Decl *ManglingContextDecl = ExprEvalContexts.back().ManglingContextDecl;
278
279
1.07M
  enum ContextKind {
280
1.07M
    Normal,
281
1.07M
    DefaultArgument,
282
1.07M
    DataMember,
283
1.07M
    StaticDataMember,
284
1.07M
    InlineVariable,
285
1.07M
    VariableTemplate
286
1.07M
  } Kind = Normal;
287
288
  // Default arguments of member function parameters that appear in a class
289
  // definition, as well as the initializers of data members, receive special
290
  // treatment. Identify them.
291
1.07M
  if (ManglingContextDecl) {
292
2.72k
    if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(ManglingContextDecl)) {
293
792
      if (const DeclContext *LexicalDC
294
792
          = Param->getDeclContext()->getLexicalParent())
295
214
        if (LexicalDC->isRecord())
296
155
          Kind = DefaultArgument;
297
1.93k
    } else if (VarDecl *Var = dyn_cast<VarDecl>(ManglingContextDecl)) {
298
1.71k
      if (Var->getDeclContext()->isRecord())
299
21
        Kind = StaticDataMember;
300
1.69k
      else if (Var->getMostRecentDecl()->isInline())
301
18
        Kind = InlineVariable;
302
1.67k
      else if (Var->getDescribedVarTemplate())
303
20
        Kind = VariableTemplate;
304
1.65k
      else if (auto *VTS = dyn_cast<VarTemplateSpecializationDecl>(Var)) {
305
11
        if (!VTS->isExplicitSpecialization())
306
11
          Kind = VariableTemplate;
307
11
      }
308
1.71k
    } else 
if (217
isa<FieldDecl>(ManglingContextDecl)217
) {
309
217
      Kind = DataMember;
310
217
    }
311
2.72k
  }
312
313
  // Itanium ABI [5.1.7]:
314
  //   In the following contexts [...] the one-definition rule requires closure
315
  //   types in different translation units to "correspond":
316
1.07M
  bool IsInNonspecializedTemplate =
317
1.07M
      inTemplateInstantiation() || 
CurContext->isDependentContext()1.06M
;
318
1.07M
  switch (Kind) {
319
1.07M
  case Normal: {
320
    //  -- the bodies of non-exported nonspecialized template functions
321
    //  -- the bodies of inline functions
322
1.07M
    if ((IsInNonspecializedTemplate &&
323
1.07M
         
!(16.3k
ManglingContextDecl16.3k
&&
isa<ParmVarDecl>(ManglingContextDecl)978
)) ||
324
1.07M
        
isInInlineFunction(CurContext)1.05M
) {
325
28.8k
      while (auto *CD = dyn_cast<CapturedDecl>(DC))
326
2.03k
        DC = CD->getParent();
327
26.7k
      return std::make_tuple(&Context.getManglingNumberContext(DC), nullptr);
328
26.7k
    }
329
330
1.04M
    return std::make_tuple(nullptr, nullptr);
331
1.07M
  }
332
333
21
  case StaticDataMember:
334
    //  -- the initializers of nonspecialized static members of template classes
335
21
    if (!IsInNonspecializedTemplate)
336
2
      return std::make_tuple(nullptr, ManglingContextDecl);
337
    // Fall through to get the current context.
338
21
    
LLVM_FALLTHROUGH19
;19
339
340
236
  case DataMember:
341
    //  -- the in-class initializers of class members
342
391
  case DefaultArgument:
343
    //  -- default arguments appearing in class definitions
344
409
  case InlineVariable:
345
    //  -- the initializers of inline variables
346
440
  case VariableTemplate:
347
    //  -- the initializers of templated variables
348
440
    return std::make_tuple(
349
440
        &Context.getManglingNumberContext(ASTContext::NeedExtraManglingDecl,
350
440
                                          ManglingContextDecl),
351
440
        ManglingContextDecl);
352
1.07M
  }
353
354
0
  llvm_unreachable("unexpected context");
355
0
}
356
357
CXXMethodDecl *Sema::startLambdaDefinition(CXXRecordDecl *Class,
358
                                           SourceRange IntroducerRange,
359
                                           TypeSourceInfo *MethodTypeInfo,
360
                                           SourceLocation EndLoc,
361
                                           ArrayRef<ParmVarDecl *> Params,
362
                                           ConstexprSpecKind ConstexprKind,
363
10.8k
                                           Expr *TrailingRequiresClause) {
364
10.8k
  QualType MethodType = MethodTypeInfo->getType();
365
10.8k
  TemplateParameterList *TemplateParams =
366
10.8k
      getGenericLambdaTemplateParameterList(getCurLambda(), *this);
367
  // If a lambda appears in a dependent context or is a generic lambda (has
368
  // template parameters) and has an 'auto' return type, deduce it to a
369
  // dependent type.
370
10.8k
  if (Class->isDependentContext() || 
TemplateParams8.28k
) {
371
4.95k
    const FunctionProtoType *FPT = MethodType->castAs<FunctionProtoType>();
372
4.95k
    QualType Result = FPT->getReturnType();
373
4.95k
    if (Result->isUndeducedType()) {
374
3.54k
      Result = SubstAutoTypeDependent(Result);
375
3.54k
      MethodType = Context.getFunctionType(Result, FPT->getParamTypes(),
376
3.54k
                                           FPT->getExtProtoInfo());
377
3.54k
    }
378
4.95k
  }
379
380
  // C++11 [expr.prim.lambda]p5:
381
  //   The closure type for a lambda-expression has a public inline function
382
  //   call operator (13.5.4) whose parameters and return type are described by
383
  //   the lambda-expression's parameter-declaration-clause and
384
  //   trailing-return-type respectively.
385
10.8k
  DeclarationName MethodName
386
10.8k
    = Context.DeclarationNames.getCXXOperatorName(OO_Call);
387
10.8k
  DeclarationNameLoc MethodNameLoc =
388
10.8k
      DeclarationNameLoc::makeCXXOperatorNameLoc(IntroducerRange);
389
10.8k
  CXXMethodDecl *Method = CXXMethodDecl::Create(
390
10.8k
      Context, Class, EndLoc,
391
10.8k
      DeclarationNameInfo(MethodName, IntroducerRange.getBegin(),
392
10.8k
                          MethodNameLoc),
393
10.8k
      MethodType, MethodTypeInfo, SC_None, getCurFPFeatures().isFPConstrained(),
394
10.8k
      /*isInline=*/true, ConstexprKind, EndLoc, TrailingRequiresClause);
395
10.8k
  Method->setAccess(AS_public);
396
10.8k
  if (!TemplateParams)
397
7.27k
    Class->addDecl(Method);
398
399
  // Temporarily set the lexical declaration context to the current
400
  // context, so that the Scope stack matches the lexical nesting.
401
10.8k
  Method->setLexicalDeclContext(CurContext);
402
  // Create a function template if we have a template parameter list
403
10.8k
  FunctionTemplateDecl *const TemplateMethod = TemplateParams ?
404
3.61k
            FunctionTemplateDecl::Create(Context, Class,
405
3.61k
                                         Method->getLocation(), MethodName,
406
3.61k
                                         TemplateParams,
407
7.27k
                                         Method) : nullptr;
408
10.8k
  if (TemplateMethod) {
409
3.61k
    TemplateMethod->setAccess(AS_public);
410
3.61k
    Method->setDescribedFunctionTemplate(TemplateMethod);
411
3.61k
    Class->addDecl(TemplateMethod);
412
3.61k
    TemplateMethod->setLexicalDeclContext(CurContext);
413
3.61k
  }
414
415
  // Add parameters.
416
10.8k
  if (!Params.empty()) {
417
5.68k
    Method->setParams(Params);
418
5.68k
    CheckParmsForFunctionDef(Params,
419
5.68k
                             /*CheckParameterNames=*/false);
420
421
5.68k
    for (auto P : Method->parameters())
422
6.86k
      P->setOwningFunction(Method);
423
5.68k
  }
424
425
10.8k
  return Method;
426
10.8k
}
427
428
void Sema::handleLambdaNumbering(
429
    CXXRecordDecl *Class, CXXMethodDecl *Method,
430
10.8k
    Optional<std::tuple<bool, unsigned, unsigned, Decl *>> Mangling) {
431
10.8k
  if (Mangling) {
432
7
    bool HasKnownInternalLinkage;
433
7
    unsigned ManglingNumber, DeviceManglingNumber;
434
7
    Decl *ManglingContextDecl;
435
7
    std::tie(HasKnownInternalLinkage, ManglingNumber, DeviceManglingNumber,
436
7
             ManglingContextDecl) = Mangling.getValue();
437
7
    Class->setLambdaMangling(ManglingNumber, ManglingContextDecl,
438
7
                             HasKnownInternalLinkage);
439
7
    Class->setDeviceLambdaManglingNumber(DeviceManglingNumber);
440
7
    return;
441
7
  }
442
443
10.8k
  auto getMangleNumberingContext =
444
10.8k
      [this](CXXRecordDecl *Class,
445
10.8k
             Decl *ManglingContextDecl) -> MangleNumberingContext * {
446
    // Get mangle numbering context if there's any extra decl context.
447
242
    if (ManglingContextDecl)
448
0
      return &Context.getManglingNumberContext(
449
0
          ASTContext::NeedExtraManglingDecl, ManglingContextDecl);
450
    // Otherwise, from that lambda's decl context.
451
242
    auto DC = Class->getDeclContext();
452
242
    while (auto *CD = dyn_cast<CapturedDecl>(DC))
453
0
      DC = CD->getParent();
454
242
    return &Context.getManglingNumberContext(DC);
455
242
  };
456
457
10.8k
  MangleNumberingContext *MCtx;
458
10.8k
  Decl *ManglingContextDecl;
459
10.8k
  std::tie(MCtx, ManglingContextDecl) =
460
10.8k
      getCurrentMangleNumberContext(Class->getDeclContext());
461
10.8k
  bool HasKnownInternalLinkage = false;
462
10.8k
  if (!MCtx && 
(4.57k
getLangOpts().CUDA4.57k
||
getLangOpts().SYCLIsDevice4.40k
||
463
4.57k
                
getLangOpts().SYCLIsHost4.33k
)) {
464
    // Force lambda numbering in CUDA/HIP as we need to name lambdas following
465
    // ODR. Both device- and host-compilation need to have a consistent naming
466
    // on kernel functions. As lambdas are potential part of these `__global__`
467
    // function names, they needs numbering following ODR.
468
    // Also force for SYCL, since we need this for the
469
    // __builtin_sycl_unique_stable_name implementation, which depends on lambda
470
    // mangling.
471
242
    MCtx = getMangleNumberingContext(Class, ManglingContextDecl);
472
242
    assert(MCtx && "Retrieving mangle numbering context failed!");
473
0
    HasKnownInternalLinkage = true;
474
242
  }
475
10.8k
  if (MCtx) {
476
6.54k
    unsigned ManglingNumber = MCtx->getManglingNumber(Method);
477
6.54k
    Class->setLambdaMangling(ManglingNumber, ManglingContextDecl,
478
6.54k
                             HasKnownInternalLinkage);
479
6.54k
    Class->setDeviceLambdaManglingNumber(MCtx->getDeviceManglingNumber(Method));
480
6.54k
  }
481
10.8k
}
482
483
void Sema::buildLambdaScope(LambdaScopeInfo *LSI,
484
                                        CXXMethodDecl *CallOperator,
485
                                        SourceRange IntroducerRange,
486
                                        LambdaCaptureDefault CaptureDefault,
487
                                        SourceLocation CaptureDefaultLoc,
488
                                        bool ExplicitParams,
489
                                        bool ExplicitResultType,
490
10.8k
                                        bool Mutable) {
491
10.8k
  LSI->CallOperator = CallOperator;
492
10.8k
  CXXRecordDecl *LambdaClass = CallOperator->getParent();
493
10.8k
  LSI->Lambda = LambdaClass;
494
10.8k
  if (CaptureDefault == LCD_ByCopy)
495
1.30k
    LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByval;
496
9.59k
  else if (CaptureDefault == LCD_ByRef)
497
2.05k
    LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByref;
498
10.8k
  LSI->CaptureDefaultLoc = CaptureDefaultLoc;
499
10.8k
  LSI->IntroducerRange = IntroducerRange;
500
10.8k
  LSI->ExplicitParams = ExplicitParams;
501
10.8k
  LSI->Mutable = Mutable;
502
503
10.8k
  if (ExplicitResultType) {
504
1.78k
    LSI->ReturnType = CallOperator->getReturnType();
505
506
1.78k
    if (!LSI->ReturnType->isDependentType() &&
507
1.78k
        
!LSI->ReturnType->isVoidType()1.33k
) {
508
849
      if (RequireCompleteType(CallOperator->getBeginLoc(), LSI->ReturnType,
509
849
                              diag::err_lambda_incomplete_result)) {
510
        // Do nothing.
511
2
      }
512
849
    }
513
9.10k
  } else {
514
9.10k
    LSI->HasImplicitReturnType = true;
515
9.10k
  }
516
10.8k
}
517
518
10.8k
void Sema::finishLambdaExplicitCaptures(LambdaScopeInfo *LSI) {
519
10.8k
  LSI->finishedExplicitCaptures();
520
10.8k
}
521
522
void Sema::ActOnLambdaExplicitTemplateParameterList(SourceLocation LAngleLoc,
523
                                                    ArrayRef<NamedDecl *> TParams,
524
                                                    SourceLocation RAngleLoc,
525
167
                                                    ExprResult RequiresClause) {
526
167
  LambdaScopeInfo *LSI = getCurLambda();
527
167
  assert(LSI && "Expected a lambda scope");
528
0
  assert(LSI->NumExplicitTemplateParams == 0 &&
529
167
         "Already acted on explicit template parameters");
530
0
  assert(LSI->TemplateParams.empty() &&
531
167
         "Explicit template parameters should come "
532
167
         "before invented (auto) ones");
533
0
  assert(!TParams.empty() &&
534
167
         "No template parameters to act on");
535
0
  LSI->TemplateParams.append(TParams.begin(), TParams.end());
536
167
  LSI->NumExplicitTemplateParams = TParams.size();
537
167
  LSI->ExplicitTemplateParamsRange = {LAngleLoc, RAngleLoc};
538
167
  LSI->RequiresClause = RequiresClause;
539
167
}
540
541
void Sema::addLambdaParameters(
542
    ArrayRef<LambdaIntroducer::LambdaCapture> Captures,
543
8.30k
    CXXMethodDecl *CallOperator, Scope *CurScope) {
544
  // Introduce our parameters into the function scope
545
8.30k
  for (unsigned p = 0, NumParams = CallOperator->getNumParams();
546
12.5k
       p < NumParams; 
++p4.22k
) {
547
4.22k
    ParmVarDecl *Param = CallOperator->getParamDecl(p);
548
549
    // If this has an identifier, add it to the scope stack.
550
4.22k
    if (CurScope && Param->getIdentifier()) {
551
3.95k
      bool Error = false;
552
      // Resolution of CWG 2211 in C++17 renders shadowing ill-formed, but we
553
      // retroactively apply it.
554
3.95k
      for (const auto &Capture : Captures) {
555
363
        if (Capture.Id == Param->getIdentifier()) {
556
11
          Error = true;
557
11
          Diag(Param->getLocation(), diag::err_parameter_shadow_capture);
558
11
          Diag(Capture.Loc, diag::note_var_explicitly_captured_here)
559
11
              << Capture.Id << true;
560
11
        }
561
363
      }
562
3.95k
      if (!Error)
563
3.94k
        CheckShadow(CurScope, Param);
564
565
3.95k
      PushOnScopeChains(Param, CurScope);
566
3.95k
    }
567
4.22k
  }
568
8.30k
}
569
570
/// If this expression is an enumerator-like expression of some type
571
/// T, return the type T; otherwise, return null.
572
///
573
/// Pointer comparisons on the result here should always work because
574
/// it's derived from either the parent of an EnumConstantDecl
575
/// (i.e. the definition) or the declaration returned by
576
/// EnumType::getDecl() (i.e. the definition).
577
531
static EnumDecl *findEnumForBlockReturn(Expr *E) {
578
  // An expression is an enumerator-like expression of type T if,
579
  // ignoring parens and parens-like expressions:
580
531
  E = E->IgnoreParens();
581
582
  //  - it is an enumerator whose enum type is T or
583
531
  if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
584
28
    if (EnumConstantDecl *D
585
28
          = dyn_cast<EnumConstantDecl>(DRE->getDecl())) {
586
28
      return cast<EnumDecl>(D->getDeclContext());
587
28
    }
588
0
    return nullptr;
589
28
  }
590
591
  //  - it is a comma expression whose RHS is an enumerator-like
592
  //    expression of type T or
593
503
  if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
594
26
    if (BO->getOpcode() == BO_Comma)
595
1
      return findEnumForBlockReturn(BO->getRHS());
596
25
    return nullptr;
597
26
  }
598
599
  //  - it is a statement-expression whose value expression is an
600
  //    enumerator-like expression of type T or
601
477
  if (StmtExpr *SE = dyn_cast<StmtExpr>(E)) {
602
1
    if (Expr *last = dyn_cast_or_null<Expr>(SE->getSubStmt()->body_back()))
603
1
      return findEnumForBlockReturn(last);
604
0
    return nullptr;
605
1
  }
606
607
  //   - it is a ternary conditional operator (not the GNU ?:
608
  //     extension) whose second and third operands are
609
  //     enumerator-like expressions of type T or
610
476
  if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
611
3
    if (EnumDecl *ED = findEnumForBlockReturn(CO->getTrueExpr()))
612
3
      if (ED == findEnumForBlockReturn(CO->getFalseExpr()))
613
3
        return ED;
614
0
    return nullptr;
615
3
  }
616
617
  // (implicitly:)
618
  //   - it is an implicit integral conversion applied to an
619
  //     enumerator-like expression of type T or
620
473
  if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
621
    // We can sometimes see integral conversions in valid
622
    // enumerator-like expressions.
623
150
    if (ICE->getCastKind() == CK_IntegralCast)
624
3
      return findEnumForBlockReturn(ICE->getSubExpr());
625
626
    // Otherwise, just rely on the type.
627
150
  }
628
629
  //   - it is an expression of that formal enum type.
630
470
  if (const EnumType *ET = E->getType()->getAs<EnumType>()) {
631
15
    return ET->getDecl();
632
15
  }
633
634
  // Otherwise, nope.
635
455
  return nullptr;
636
470
}
637
638
/// Attempt to find a type T for which the returned expression of the
639
/// given statement is an enumerator-like expression of that type.
640
717
static EnumDecl *findEnumForBlockReturn(ReturnStmt *ret) {
641
717
  if (Expr *retValue = ret->getRetValue())
642
520
    return findEnumForBlockReturn(retValue);
643
197
  return nullptr;
644
717
}
645
646
/// Attempt to find a common type T for which all of the returned
647
/// expressions in a block are enumerator-like expressions of that
648
/// type.
649
702
static EnumDecl *findCommonEnumForBlockReturns(ArrayRef<ReturnStmt*> returns) {
650
702
  ArrayRef<ReturnStmt*>::iterator i = returns.begin(), e = returns.end();
651
652
  // Try to find one for the first return.
653
702
  EnumDecl *ED = findEnumForBlockReturn(*i);
654
702
  if (!ED) 
return nullptr675
;
655
656
  // Check that the rest of the returns have the same enum.
657
40
  
for (++i; 27
i != e;
++i13
) {
658
15
    if (findEnumForBlockReturn(*i) != ED)
659
2
      return nullptr;
660
15
  }
661
662
  // Never infer an anonymous enum type.
663
25
  if (!ED->hasNameForLinkage()) 
return nullptr3
;
664
665
22
  return ED;
666
25
}
667
668
/// Adjust the given return statements so that they formally return
669
/// the given type.  It should require, at most, an IntegralCast.
670
static void adjustBlockReturnsToEnum(Sema &S, ArrayRef<ReturnStmt*> returns,
671
22
                                     QualType returnType) {
672
22
  for (ArrayRef<ReturnStmt*>::iterator
673
57
         i = returns.begin(), e = returns.end(); i != e; 
++i35
) {
674
35
    ReturnStmt *ret = *i;
675
35
    Expr *retValue = ret->getRetValue();
676
35
    if (S.Context.hasSameType(retValue->getType(), returnType))
677
14
      continue;
678
679
    // Right now we only support integral fixup casts.
680
21
    assert(returnType->isIntegralOrUnscopedEnumerationType());
681
0
    assert(retValue->getType()->isIntegralOrUnscopedEnumerationType());
682
683
0
    ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(retValue);
684
685
21
    Expr *E = (cleanups ? 
cleanups->getSubExpr()0
: retValue);
686
21
    E = ImplicitCastExpr::Create(S.Context, returnType, CK_IntegralCast, E,
687
21
                                 /*base path*/ nullptr, VK_PRValue,
688
21
                                 FPOptionsOverride());
689
21
    if (cleanups) {
690
0
      cleanups->setSubExpr(E);
691
21
    } else {
692
21
      ret->setRetValue(E);
693
21
    }
694
21
  }
695
22
}
696
697
5.60k
void Sema::deduceClosureReturnType(CapturingScopeInfo &CSI) {
698
5.60k
  assert(CSI.HasImplicitReturnType);
699
  // If it was ever a placeholder, it had to been deduced to DependentTy.
700
0
  assert(CSI.ReturnType.isNull() || !CSI.ReturnType->isUndeducedType());
701
0
  assert((!isa<LambdaScopeInfo>(CSI) || !getLangOpts().CPlusPlus14) &&
702
5.60k
         "lambda expressions use auto deduction in C++14 onwards");
703
704
  // C++ core issue 975:
705
  //   If a lambda-expression does not include a trailing-return-type,
706
  //   it is as if the trailing-return-type denotes the following type:
707
  //     - if there are no return statements in the compound-statement,
708
  //       or all return statements return either an expression of type
709
  //       void or no expression or braced-init-list, the type void;
710
  //     - otherwise, if all return statements return an expression
711
  //       and the types of the returned expressions after
712
  //       lvalue-to-rvalue conversion (4.1 [conv.lval]),
713
  //       array-to-pointer conversion (4.2 [conv.array]), and
714
  //       function-to-pointer conversion (4.3 [conv.func]) are the
715
  //       same, that common type;
716
  //     - otherwise, the program is ill-formed.
717
  //
718
  // C++ core issue 1048 additionally removes top-level cv-qualifiers
719
  // from the types of returned expressions to match the C++14 auto
720
  // deduction rules.
721
  //
722
  // In addition, in blocks in non-C++ modes, if all of the return
723
  // statements are enumerator-like expressions of some type T, where
724
  // T has a name for linkage, then we infer the return type of the
725
  // block to be that type.
726
727
  // First case: no return statements, implicit void return type.
728
0
  ASTContext &Ctx = getASTContext();
729
5.60k
  if (CSI.Returns.empty()) {
730
    // It's possible there were simply no /valid/ return statements.
731
    // In this case, the first one we found may have at least given us a type.
732
4.29k
    if (CSI.ReturnType.isNull())
733
4.28k
      CSI.ReturnType = Ctx.VoidTy;
734
4.29k
    return;
735
4.29k
  }
736
737
  // Second case: at least one return statement has dependent type.
738
  // Delay type checking until instantiation.
739
1.31k
  assert(!CSI.ReturnType.isNull() && "We should have a tentative return type.");
740
1.31k
  if (CSI.ReturnType->isDependentType())
741
72
    return;
742
743
  // Try to apply the enum-fuzz rule.
744
1.24k
  if (!getLangOpts().CPlusPlus) {
745
702
    assert(isa<BlockScopeInfo>(CSI));
746
0
    const EnumDecl *ED = findCommonEnumForBlockReturns(CSI.Returns);
747
702
    if (ED) {
748
22
      CSI.ReturnType = Context.getTypeDeclType(ED);
749
22
      adjustBlockReturnsToEnum(*this, CSI.Returns, CSI.ReturnType);
750
22
      return;
751
22
    }
752
702
  }
753
754
  // Third case: only one return statement. Don't bother doing extra work!
755
1.21k
  if (CSI.Returns.size() == 1)
756
1.17k
    return;
757
758
  // General case: many return statements.
759
  // Check that they all have compatible return types.
760
761
  // We require the return types to strictly match here.
762
  // Note that we've already done the required promotions as part of
763
  // processing the return statement.
764
111
  
for (const ReturnStmt *RS : CSI.Returns)43
{
765
111
    const Expr *RetE = RS->getRetValue();
766
767
111
    QualType ReturnType =
768
111
        (RetE ? 
RetE->getType()106
:
Context.VoidTy5
).getUnqualifiedType();
769
111
    if (Context.getCanonicalFunctionResultType(ReturnType) ==
770
111
          Context.getCanonicalFunctionResultType(CSI.ReturnType)) {
771
      // Use the return type with the strictest possible nullability annotation.
772
102
      auto RetTyNullability = ReturnType->getNullability(Ctx);
773
102
      auto BlockNullability = CSI.ReturnType->getNullability(Ctx);
774
102
      if (BlockNullability &&
775
102
          
(4
!RetTyNullability4
||
776
4
           
hasWeakerNullability(*RetTyNullability, *BlockNullability)2
))
777
2
        CSI.ReturnType = ReturnType;
778
102
      continue;
779
102
    }
780
781
    // FIXME: This is a poor diagnostic for ReturnStmts without expressions.
782
    // TODO: It's possible that the *first* return is the divergent one.
783
9
    Diag(RS->getBeginLoc(),
784
9
         diag::err_typecheck_missing_return_type_incompatible)
785
9
        << ReturnType << CSI.ReturnType << isa<LambdaScopeInfo>(CSI);
786
    // Continue iterating so that we keep emitting diagnostics.
787
9
  }
788
43
}
789
790
QualType Sema::buildLambdaInitCaptureInitialization(
791
    SourceLocation Loc, bool ByRef, SourceLocation EllipsisLoc,
792
    Optional<unsigned> NumExpansions, IdentifierInfo *Id, bool IsDirectInit,
793
582
    Expr *&Init) {
794
  // Create an 'auto' or 'auto&' TypeSourceInfo that we can use to
795
  // deduce against.
796
582
  QualType DeductType = Context.getAutoDeductType();
797
582
  TypeLocBuilder TLB;
798
582
  AutoTypeLoc TL = TLB.push<AutoTypeLoc>(DeductType);
799
582
  TL.setNameLoc(Loc);
800
582
  if (ByRef) {
801
115
    DeductType = BuildReferenceType(DeductType, true, Loc, Id);
802
115
    assert(!DeductType.isNull() && "can't build reference to auto");
803
0
    TLB.push<ReferenceTypeLoc>(DeductType).setSigilLoc(Loc);
804
115
  }
805
582
  if (EllipsisLoc.isValid()) {
806
64
    if (Init->containsUnexpandedParameterPack()) {
807
63
      Diag(EllipsisLoc, getLangOpts().CPlusPlus20
808
63
                            ? 
diag::warn_cxx17_compat_init_capture_pack32
809
63
                            : 
diag::ext_init_capture_pack31
);
810
63
      DeductType = Context.getPackExpansionType(DeductType, NumExpansions,
811
63
                                                /*ExpectPackInType=*/false);
812
63
      TLB.push<PackExpansionTypeLoc>(DeductType).setEllipsisLoc(EllipsisLoc);
813
63
    } else {
814
      // Just ignore the ellipsis for now and form a non-pack variable. We'll
815
      // diagnose this later when we try to capture it.
816
1
    }
817
64
  }
818
582
  TypeSourceInfo *TSI = TLB.getTypeSourceInfo(Context, DeductType);
819
820
  // Deduce the type of the init capture.
821
582
  QualType DeducedType = deduceVarTypeFromInitializer(
822
582
      /*VarDecl*/nullptr, DeclarationName(Id), DeductType, TSI,
823
582
      SourceRange(Loc, Loc), IsDirectInit, Init);
824
582
  if (DeducedType.isNull())
825
37
    return QualType();
826
827
  // Are we a non-list direct initialization?
828
545
  ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
829
830
  // Perform initialization analysis and ensure any implicit conversions
831
  // (such as lvalue-to-rvalue) are enforced.
832
545
  InitializedEntity Entity =
833
545
      InitializedEntity::InitializeLambdaCapture(Id, DeducedType, Loc);
834
545
  InitializationKind Kind =
835
545
      IsDirectInit
836
545
          ? 
(160
CXXDirectInit160
? InitializationKind::CreateDirect(
837
140
                                 Loc, Init->getBeginLoc(), Init->getEndLoc())
838
160
                           : 
InitializationKind::CreateDirectList(Loc)20
)
839
545
          : 
InitializationKind::CreateCopy(Loc, Init->getBeginLoc())385
;
840
841
545
  MultiExprArg Args = Init;
842
545
  if (CXXDirectInit)
843
140
    Args =
844
140
        MultiExprArg(CXXDirectInit->getExprs(), CXXDirectInit->getNumExprs());
845
545
  QualType DclT;
846
545
  InitializationSequence InitSeq(*this, Entity, Kind, Args);
847
545
  ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
848
849
545
  if (Result.isInvalid())
850
4
    return QualType();
851
852
541
  Init = Result.getAs<Expr>();
853
541
  return DeducedType;
854
545
}
855
856
VarDecl *Sema::createLambdaInitCaptureVarDecl(SourceLocation Loc,
857
                                              QualType InitCaptureType,
858
                                              SourceLocation EllipsisLoc,
859
                                              IdentifierInfo *Id,
860
539
                                              unsigned InitStyle, Expr *Init) {
861
  // FIXME: Retain the TypeSourceInfo from buildLambdaInitCaptureInitialization
862
  // rather than reconstructing it here.
863
539
  TypeSourceInfo *TSI = Context.getTrivialTypeSourceInfo(InitCaptureType, Loc);
864
539
  if (auto PETL = TSI->getTypeLoc().getAs<PackExpansionTypeLoc>())
865
61
    PETL.setEllipsisLoc(EllipsisLoc);
866
867
  // Create a dummy variable representing the init-capture. This is not actually
868
  // used as a variable, and only exists as a way to name and refer to the
869
  // init-capture.
870
  // FIXME: Pass in separate source locations for '&' and identifier.
871
539
  VarDecl *NewVD = VarDecl::Create(Context, CurContext, Loc,
872
539
                                   Loc, Id, InitCaptureType, TSI, SC_Auto);
873
539
  NewVD->setInitCapture(true);
874
539
  NewVD->setReferenced(true);
875
  // FIXME: Pass in a VarDecl::InitializationStyle.
876
539
  NewVD->setInitStyle(static_cast<VarDecl::InitializationStyle>(InitStyle));
877
539
  NewVD->markUsed(Context);
878
539
  NewVD->setInit(Init);
879
539
  if (NewVD->isParameterPack())
880
61
    getCurLambda()->LocalPacks.push_back(NewVD);
881
539
  return NewVD;
882
539
}
883
884
537
void Sema::addInitCapture(LambdaScopeInfo *LSI, VarDecl *Var) {
885
537
  assert(Var->isInitCapture() && "init capture flag should be set");
886
0
  LSI->addCapture(Var, /*isBlock*/false, Var->getType()->isReferenceType(),
887
537
                  /*isNested*/false, Var->getLocation(), SourceLocation(),
888
537
                  Var->getType(), /*Invalid*/false);
889
537
}
890
891
void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
892
                                        Declarator &ParamInfo,
893
8.30k
                                        Scope *CurScope) {
894
8.30k
  LambdaScopeInfo *const LSI = getCurLambda();
895
8.30k
  assert(LSI && "LambdaScopeInfo should be on stack!");
896
897
  // Determine if we're within a context where we know that the lambda will
898
  // be dependent, because there are template parameters in scope.
899
0
  CXXRecordDecl::LambdaDependencyKind LambdaDependencyKind =
900
8.30k
      CXXRecordDecl::LDK_Unknown;
901
8.30k
  if (LSI->NumExplicitTemplateParams > 0) {
902
167
    auto *TemplateParamScope = CurScope->getTemplateParamParent();
903
167
    assert(TemplateParamScope &&
904
167
           "Lambda with explicit template param list should establish a "
905
167
           "template param scope");
906
0
    assert(TemplateParamScope->getParent());
907
167
    if (TemplateParamScope->getParent()->getTemplateParamParent() != nullptr)
908
16
      LambdaDependencyKind = CXXRecordDecl::LDK_AlwaysDependent;
909
8.14k
  } else if (CurScope->getTemplateParamParent() != nullptr) {
910
1.48k
    LambdaDependencyKind = CXXRecordDecl::LDK_AlwaysDependent;
911
1.48k
  }
912
913
  // Determine the signature of the call operator.
914
0
  TypeSourceInfo *MethodTyInfo;
915
8.30k
  bool ExplicitParams = true;
916
8.30k
  bool ExplicitResultType = true;
917
8.30k
  bool ContainsUnexpandedParameterPack = false;
918
8.30k
  SourceLocation EndLoc;
919
8.30k
  SmallVector<ParmVarDecl *, 8> Params;
920
8.30k
  if (ParamInfo.getNumTypeObjects() == 0) {
921
    // C++11 [expr.prim.lambda]p4:
922
    //   If a lambda-expression does not include a lambda-declarator, it is as
923
    //   if the lambda-declarator were ().
924
1.80k
    FunctionProtoType::ExtProtoInfo EPI(Context.getDefaultCallingConvention(
925
1.80k
        /*IsVariadic=*/false, /*IsCXXMethod=*/true));
926
1.80k
    EPI.HasTrailingReturn = true;
927
1.80k
    EPI.TypeQuals.addConst();
928
1.80k
    LangAS AS = getDefaultCXXMethodAddrSpace();
929
1.80k
    if (AS != LangAS::Default)
930
2
      EPI.TypeQuals.addAddressSpace(AS);
931
932
    // C++1y [expr.prim.lambda]:
933
    //   The lambda return type is 'auto', which is replaced by the
934
    //   trailing-return type if provided and/or deduced from 'return'
935
    //   statements
936
    // We don't do this before C++1y, because we don't support deduced return
937
    // types there.
938
1.80k
    QualType DefaultTypeForNoTrailingReturn =
939
1.80k
        getLangOpts().CPlusPlus14 ? 
Context.getAutoDeductType()1.21k
940
1.80k
                                  : 
Context.DependentTy594
;
941
1.80k
    QualType MethodTy =
942
1.80k
        Context.getFunctionType(DefaultTypeForNoTrailingReturn, None, EPI);
943
1.80k
    MethodTyInfo = Context.getTrivialTypeSourceInfo(MethodTy);
944
1.80k
    ExplicitParams = false;
945
1.80k
    ExplicitResultType = false;
946
1.80k
    EndLoc = Intro.Range.getEnd();
947
6.49k
  } else {
948
6.49k
    assert(ParamInfo.isFunctionDeclarator() &&
949
6.49k
           "lambda-declarator is a function");
950
0
    DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getFunctionTypeInfo();
951
952
    // C++11 [expr.prim.lambda]p5:
953
    //   This function call operator is declared const (9.3.1) if and only if
954
    //   the lambda-expression's parameter-declaration-clause is not followed
955
    //   by mutable. It is neither virtual nor declared volatile. [...]
956
6.49k
    if (!FTI.hasMutableQualifier()) {
957
6.30k
      FTI.getOrCreateMethodQualifiers().SetTypeQual(DeclSpec::TQ_const,
958
6.30k
                                                    SourceLocation());
959
6.30k
    }
960
961
6.49k
    MethodTyInfo = GetTypeForDeclarator(ParamInfo, CurScope);
962
6.49k
    assert(MethodTyInfo && "no type from lambda-declarator");
963
0
    EndLoc = ParamInfo.getSourceRange().getEnd();
964
965
6.49k
    ExplicitResultType = FTI.hasTrailingReturnType();
966
967
6.49k
    if (FTIHasNonVoidParameters(FTI)) {
968
3.64k
      Params.reserve(FTI.NumParams);
969
7.87k
      for (unsigned i = 0, e = FTI.NumParams; i != e; 
++i4.22k
)
970
4.22k
        Params.push_back(cast<ParmVarDecl>(FTI.Params[i].Param));
971
3.64k
    }
972
973
    // Check for unexpanded parameter packs in the method type.
974
6.49k
    if (MethodTyInfo->getType()->containsUnexpandedParameterPack())
975
50
      DiagnoseUnexpandedParameterPack(Intro.Range.getBegin(), MethodTyInfo,
976
50
                                      UPPC_DeclarationType);
977
6.49k
  }
978
979
0
  CXXRecordDecl *Class = createLambdaClosureType(
980
8.30k
      Intro.Range, MethodTyInfo, LambdaDependencyKind, Intro.Default);
981
8.30k
  CXXMethodDecl *Method =
982
8.30k
      startLambdaDefinition(Class, Intro.Range, MethodTyInfo, EndLoc, Params,
983
8.30k
                            ParamInfo.getDeclSpec().getConstexprSpecifier(),
984
8.30k
                            ParamInfo.getTrailingRequiresClause());
985
8.30k
  if (ExplicitParams)
986
6.49k
    CheckCXXDefaultArguments(Method);
987
988
  // This represents the function body for the lambda function, check if we
989
  // have to apply optnone due to a pragma.
990
8.30k
  AddRangeBasedOptnone(Method);
991
992
  // code_seg attribute on lambda apply to the method.
993
8.30k
  if (Attr *A = getImplicitCodeSegOrSectionAttrForFunction(Method, /*IsDefinition=*/true))
994
2
    Method->addAttr(A);
995
996
  // Attributes on the lambda apply to the method.
997
8.30k
  ProcessDeclAttributes(CurScope, Method, ParamInfo);
998
999
  // CUDA lambdas get implicit host and device attributes.
1000
8.30k
  if (getLangOpts().CUDA)
1001
221
    CUDASetLambdaAttrs(Method);
1002
1003
  // OpenMP lambdas might get assumumption attributes.
1004
8.30k
  if (LangOpts.OpenMP)
1005
1.40k
    ActOnFinishedFunctionDefinitionInOpenMPAssumeScope(Method);
1006
1007
  // Number the lambda for linkage purposes if necessary.
1008
8.30k
  handleLambdaNumbering(Class, Method);
1009
1010
  // Introduce the function call operator as the current declaration context.
1011
8.30k
  PushDeclContext(CurScope, Method);
1012
1013
  // Build the lambda scope.
1014
8.30k
  buildLambdaScope(LSI, Method, Intro.Range, Intro.Default, Intro.DefaultLoc,
1015
8.30k
                   ExplicitParams, ExplicitResultType, !Method->isConst());
1016
1017
  // C++11 [expr.prim.lambda]p9:
1018
  //   A lambda-expression whose smallest enclosing scope is a block scope is a
1019
  //   local lambda expression; any other lambda expression shall not have a
1020
  //   capture-default or simple-capture in its lambda-introducer.
1021
  //
1022
  // For simple-captures, this is covered by the check below that any named
1023
  // entity is a variable that can be captured.
1024
  //
1025
  // For DR1632, we also allow a capture-default in any context where we can
1026
  // odr-use 'this' (in particular, in a default initializer for a non-static
1027
  // data member).
1028
8.30k
  if (Intro.Default != LCD_None && 
!Class->getParent()->isFunctionOrMethod()2.80k
&&
1029
8.30k
      
(37
getCurrentThisType().isNull()37
||
1030
37
       CheckCXXThisCapture(SourceLocation(), /*Explicit*/true,
1031
29
                           /*BuildAndDiagnose*/false)))
1032
8
    Diag(Intro.DefaultLoc, diag::err_capture_default_non_local);
1033
1034
  // Distinct capture names, for diagnostics.
1035
8.30k
  llvm::SmallSet<IdentifierInfo*, 8> CaptureNames;
1036
1037
  // Handle explicit captures.
1038
8.30k
  SourceLocation PrevCaptureLoc
1039
8.30k
    = Intro.Default == LCD_None? 
Intro.Range.getBegin()5.50k
:
Intro.DefaultLoc2.80k
;
1040
10.0k
  for (auto C = Intro.Captures.begin(), E = Intro.Captures.end(); C != E;
1041
8.30k
       
PrevCaptureLoc = C->Loc, ++C1.70k
) {
1042
1.70k
    if (C->Kind == LCK_This || 
C->Kind == LCK_StarThis1.44k
) {
1043
386
      if (C->Kind == LCK_StarThis)
1044
121
        Diag(C->Loc, !getLangOpts().CPlusPlus17
1045
121
                             ? 
diag::ext_star_this_lambda_capture_cxx172
1046
121
                             : 
diag::warn_cxx14_compat_star_this_lambda_capture119
);
1047
1048
      // C++11 [expr.prim.lambda]p8:
1049
      //   An identifier or this shall not appear more than once in a
1050
      //   lambda-capture.
1051
386
      if (LSI->isCXXThisCaptured()) {
1052
5
        Diag(C->Loc, diag::err_capture_more_than_once)
1053
5
            << "'this'" << SourceRange(LSI->getCXXThisCapture().getLocation())
1054
5
            << FixItHint::CreateRemoval(
1055
5
                   SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
1056
5
        continue;
1057
5
      }
1058
1059
      // C++2a [expr.prim.lambda]p8:
1060
      //  If a lambda-capture includes a capture-default that is =,
1061
      //  each simple-capture of that lambda-capture shall be of the form
1062
      //  "&identifier", "this", or "* this". [ Note: The form [&,this] is
1063
      //  redundant but accepted for compatibility with ISO C++14. --end note ]
1064
381
      if (Intro.Default == LCD_ByCopy && 
C->Kind != LCK_StarThis9
)
1065
5
        Diag(C->Loc, !getLangOpts().CPlusPlus20
1066
5
                         ? 
diag::ext_equals_this_lambda_capture_cxx203
1067
5
                         : 
diag::warn_cxx17_compat_equals_this_lambda_capture2
);
1068
1069
      // C++11 [expr.prim.lambda]p12:
1070
      //   If this is captured by a local lambda expression, its nearest
1071
      //   enclosing function shall be a non-static member function.
1072
381
      QualType ThisCaptureType = getCurrentThisType();
1073
381
      if (ThisCaptureType.isNull()) {
1074
5
        Diag(C->Loc, diag::err_this_capture) << true;
1075
5
        continue;
1076
5
      }
1077
1078
376
      CheckCXXThisCapture(C->Loc, /*Explicit=*/true, /*BuildAndDiagnose*/ true,
1079
376
                          /*FunctionScopeIndexToStopAtPtr*/ nullptr,
1080
376
                          C->Kind == LCK_StarThis);
1081
376
      if (!LSI->Captures.empty())
1082
374
        LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange;
1083
376
      continue;
1084
381
    }
1085
1086
1.32k
    assert(C->Id && "missing identifier for capture");
1087
1088
1.32k
    if (C->Init.isInvalid())
1089
7
      continue;
1090
1091
1.31k
    VarDecl *Var = nullptr;
1092
1.31k
    if (C->Init.isUsable()) {
1093
447
      Diag(C->Loc, getLangOpts().CPlusPlus14
1094
447
                       ? 
diag::warn_cxx11_compat_init_capture396
1095
447
                       : 
diag::ext_init_capture51
);
1096
1097
      // If the initializer expression is usable, but the InitCaptureType
1098
      // is not, then an error has occurred - so ignore the capture for now.
1099
      // for e.g., [n{0}] { }; <-- if no <initializer_list> is included.
1100
      // FIXME: we should create the init capture variable and mark it invalid
1101
      // in this case.
1102
447
      if (C->InitCaptureType.get().isNull())
1103
33
        continue;
1104
1105
414
      if (C->Init.get()->containsUnexpandedParameterPack() &&
1106
414
          
!C->InitCaptureType.get()->getAs<PackExpansionType>()77
)
1107
16
        DiagnoseUnexpandedParameterPack(C->Init.get(), UPPC_Initializer);
1108
1109
414
      unsigned InitStyle;
1110
414
      switch (C->InitKind) {
1111
0
      case LambdaCaptureInitKind::NoInit:
1112
0
        llvm_unreachable("not an init-capture?");
1113
301
      case LambdaCaptureInitKind::CopyInit:
1114
301
        InitStyle = VarDecl::CInit;
1115
301
        break;
1116
94
      case LambdaCaptureInitKind::DirectInit:
1117
94
        InitStyle = VarDecl::CallInit;
1118
94
        break;
1119
19
      case LambdaCaptureInitKind::ListInit:
1120
19
        InitStyle = VarDecl::ListInit;
1121
19
        break;
1122
414
      }
1123
414
      Var = createLambdaInitCaptureVarDecl(C->Loc, C->InitCaptureType.get(),
1124
414
                                           C->EllipsisLoc, C->Id, InitStyle,
1125
414
                                           C->Init.get());
1126
      // C++1y [expr.prim.lambda]p11:
1127
      //   An init-capture behaves as if it declares and explicitly
1128
      //   captures a variable [...] whose declarative region is the
1129
      //   lambda-expression's compound-statement
1130
414
      if (Var)
1131
414
        PushOnScopeChains(Var, CurScope, false);
1132
869
    } else {
1133
869
      assert(C->InitKind == LambdaCaptureInitKind::NoInit &&
1134
869
             "init capture has valid but null init?");
1135
1136
      // C++11 [expr.prim.lambda]p8:
1137
      //   If a lambda-capture includes a capture-default that is &, the
1138
      //   identifiers in the lambda-capture shall not be preceded by &.
1139
      //   If a lambda-capture includes a capture-default that is =, [...]
1140
      //   each identifier it contains shall be preceded by &.
1141
869
      if (C->Kind == LCK_ByRef && 
Intro.Default == LCD_ByRef249
) {
1142
7
        Diag(C->Loc, diag::err_reference_capture_with_reference_default)
1143
7
            << FixItHint::CreateRemoval(
1144
7
                SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
1145
7
        continue;
1146
862
      } else if (C->Kind == LCK_ByCopy && 
Intro.Default == LCD_ByCopy620
) {
1147
1
        Diag(C->Loc, diag::err_copy_capture_with_copy_default)
1148
1
            << FixItHint::CreateRemoval(
1149
1
                SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
1150
1
        continue;
1151
1
      }
1152
1153
      // C++11 [expr.prim.lambda]p10:
1154
      //   The identifiers in a capture-list are looked up using the usual
1155
      //   rules for unqualified name lookup (3.4.1)
1156
861
      DeclarationNameInfo Name(C->Id, C->Loc);
1157
861
      LookupResult R(*this, Name, LookupOrdinaryName);
1158
861
      LookupName(R, CurScope);
1159
861
      if (R.isAmbiguous())
1160
1
        continue;
1161
860
      if (R.empty()) {
1162
        // FIXME: Disable corrections that would add qualification?
1163
1
        CXXScopeSpec ScopeSpec;
1164
1
        DeclFilterCCC<VarDecl> Validator{};
1165
1
        if (DiagnoseEmptyLookup(CurScope, ScopeSpec, R, Validator))
1166
0
          continue;
1167
1
      }
1168
1169
860
      Var = R.getAsSingle<VarDecl>();
1170
860
      if (Var && 
DiagnoseUseOfDecl(Var, C->Loc)846
)
1171
2
        continue;
1172
860
    }
1173
1174
    // C++11 [expr.prim.lambda]p8:
1175
    //   An identifier or this shall not appear more than once in a
1176
    //   lambda-capture.
1177
1.27k
    if (!CaptureNames.insert(C->Id).second) {
1178
9
      if (Var && LSI->isCaptured(Var)) {
1179
7
        Diag(C->Loc, diag::err_capture_more_than_once)
1180
7
            << C->Id << SourceRange(LSI->getCapture(Var).getLocation())
1181
7
            << FixItHint::CreateRemoval(
1182
7
                   SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
1183
7
      } else
1184
        // Previous capture captured something different (one or both was
1185
        // an init-cpature): no fixit.
1186
2
        Diag(C->Loc, diag::err_capture_more_than_once) << C->Id;
1187
9
      continue;
1188
9
    }
1189
1190
    // C++11 [expr.prim.lambda]p10:
1191
    //   [...] each such lookup shall find a variable with automatic storage
1192
    //   duration declared in the reaching scope of the local lambda expression.
1193
    // Note that the 'reaching scope' check happens in tryCaptureVariable().
1194
1.26k
    if (!Var) {
1195
14
      Diag(C->Loc, diag::err_capture_does_not_name_variable) << C->Id;
1196
14
      continue;
1197
14
    }
1198
1199
    // Ignore invalid decls; they'll just confuse the code later.
1200
1.24k
    if (Var->isInvalidDecl())
1201
4
      continue;
1202
1203
1.24k
    if (!Var->hasLocalStorage()) {
1204
2
      Diag(C->Loc, diag::err_capture_non_automatic_variable) << C->Id;
1205
2
      Diag(Var->getLocation(), diag::note_previous_decl) << C->Id;
1206
2
      continue;
1207
2
    }
1208
1209
    // C++11 [expr.prim.lambda]p23:
1210
    //   A capture followed by an ellipsis is a pack expansion (14.5.3).
1211
1.24k
    SourceLocation EllipsisLoc;
1212
1.24k
    if (C->EllipsisLoc.isValid()) {
1213
142
      if (Var->isParameterPack()) {
1214
138
        EllipsisLoc = C->EllipsisLoc;
1215
138
      } else {
1216
4
        Diag(C->EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
1217
4
            << (C->Init.isUsable() ? 
C->Init.get()->getSourceRange()1
1218
4
                                   : 
SourceRange(C->Loc)3
);
1219
1220
        // Just ignore the ellipsis.
1221
4
      }
1222
1.10k
    } else if (Var->isParameterPack()) {
1223
13
      ContainsUnexpandedParameterPack = true;
1224
13
    }
1225
1226
1.24k
    if (C->Init.isUsable()) {
1227
412
      addInitCapture(LSI, Var);
1228
831
    } else {
1229
831
      TryCaptureKind Kind = C->Kind == LCK_ByRef ? 
TryCapture_ExplicitByRef237
:
1230
831
                                                   
TryCapture_ExplicitByVal594
;
1231
831
      tryCaptureVariable(Var, C->Loc, Kind, EllipsisLoc);
1232
831
    }
1233
1.24k
    if (!LSI->Captures.empty())
1234
1.23k
      LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange;
1235
1.24k
  }
1236
8.30k
  finishLambdaExplicitCaptures(LSI);
1237
1238
8.30k
  LSI->ContainsUnexpandedParameterPack |= ContainsUnexpandedParameterPack;
1239
1240
  // Add lambda parameters into scope.
1241
8.30k
  addLambdaParameters(Intro.Captures, Method, CurScope);
1242
1243
  // Enter a new evaluation context to insulate the lambda from any
1244
  // cleanups from the enclosing full-expression.
1245
8.30k
  PushExpressionEvaluationContext(
1246
8.30k
      LSI->CallOperator->isConsteval()
1247
8.30k
          ? 
ExpressionEvaluationContext::ImmediateFunctionContext6
1248
8.30k
          : 
ExpressionEvaluationContext::PotentiallyEvaluated8.30k
);
1249
8.30k
}
1250
1251
void Sema::ActOnLambdaError(SourceLocation StartLoc, Scope *CurScope,
1252
210
                            bool IsInstantiation) {
1253
210
  LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(FunctionScopes.back());
1254
1255
  // Leave the expression-evaluation context.
1256
210
  DiscardCleanupsInEvaluationContext();
1257
210
  PopExpressionEvaluationContext();
1258
1259
  // Leave the context of the lambda.
1260
210
  if (!IsInstantiation)
1261
189
    PopDeclContext();
1262
1263
  // Finalize the lambda.
1264
210
  CXXRecordDecl *Class = LSI->Lambda;
1265
210
  Class->setInvalidDecl();
1266
210
  SmallVector<Decl*, 4> Fields(Class->fields());
1267
210
  ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
1268
210
              SourceLocation(), ParsedAttributesView());
1269
210
  CheckCompletedCXXClass(nullptr, Class);
1270
1271
210
  PopFunctionScopeInfo();
1272
210
}
1273
1274
template <typename Func>
1275
static void repeatForLambdaConversionFunctionCallingConvs(
1276
5.77k
    Sema &S, const FunctionProtoType &CallOpProto, Func F) {
1277
5.77k
  CallingConv DefaultFree = S.Context.getDefaultCallingConvention(
1278
5.77k
      CallOpProto.isVariadic(), /*IsCXXMethod=*/false);
1279
5.77k
  CallingConv DefaultMember = S.Context.getDefaultCallingConvention(
1280
5.77k
      CallOpProto.isVariadic(), /*IsCXXMethod=*/true);
1281
5.77k
  CallingConv CallOpCC = CallOpProto.getCallConv();
1282
1283
  /// Implement emitting a version of the operator for many of the calling
1284
  /// conventions for MSVC, as described here:
1285
  /// https://devblogs.microsoft.com/oldnewthing/20150220-00/?p=44623.
1286
  /// Experimentally, we determined that cdecl, stdcall, fastcall, and
1287
  /// vectorcall are generated by MSVC when it is supported by the target.
1288
  /// Additionally, we are ensuring that the default-free/default-member and
1289
  /// call-operator calling convention are generated as well.
1290
  /// NOTE: We intentionally generate a 'thiscall' on Win32 implicitly from the
1291
  /// 'member default', despite MSVC not doing so. We do this in order to ensure
1292
  /// that someone who intentionally places 'thiscall' on the lambda call
1293
  /// operator will still get that overload, since we don't have the a way of
1294
  /// detecting the attribute by the time we get here.
1295
5.77k
  if (S.getLangOpts().MSVCCompat) {
1296
82
    CallingConv Convs[] = {
1297
82
        CC_C,        CC_X86StdCall, CC_X86FastCall, CC_X86VectorCall,
1298
82
        DefaultFree, DefaultMember, CallOpCC};
1299
82
    llvm::sort(Convs);
1300
82
    llvm::iterator_range<CallingConv *> Range(
1301
82
        std::begin(Convs), std::unique(std::begin(Convs), std::end(Convs)));
1302
82
    const TargetInfo &TI = S.getASTContext().getTargetInfo();
1303
1304
330
    for (CallingConv C : Range) {
1305
330
      if (TI.checkCallingConvention(C) == TargetInfo::CCCR_OK)
1306
170
        F(C);
1307
330
    }
1308
82
    return;
1309
82
  }
1310
1311
5.69k
  if (CallOpCC == DefaultMember && 
DefaultMember != DefaultFree5.67k
) {
1312
1.60k
    F(DefaultFree);
1313
1.60k
    F(DefaultMember);
1314
4.08k
  } else {
1315
4.08k
    F(CallOpCC);
1316
4.08k
  }
1317
5.69k
}
1318
1319
// Returns the 'standard' calling convention to be used for the lambda
1320
// conversion function, that is, the 'free' function calling convention unless
1321
// it is overridden by a non-default calling convention attribute.
1322
static CallingConv
1323
getLambdaConversionFunctionCallConv(Sema &S,
1324
162
                                    const FunctionProtoType *CallOpProto) {
1325
162
  CallingConv DefaultFree = S.Context.getDefaultCallingConvention(
1326
162
      CallOpProto->isVariadic(), /*IsCXXMethod=*/false);
1327
162
  CallingConv DefaultMember = S.Context.getDefaultCallingConvention(
1328
162
      CallOpProto->isVariadic(), /*IsCXXMethod=*/true);
1329
162
  CallingConv CallOpCC = CallOpProto->getCallConv();
1330
1331
  // If the call-operator hasn't been changed, return both the 'free' and
1332
  // 'member' function calling convention.
1333
162
  if (CallOpCC == DefaultMember && DefaultMember != DefaultFree)
1334
0
    return DefaultFree;
1335
162
  return CallOpCC;
1336
162
}
1337
1338
QualType Sema::getLambdaConversionFunctionResultType(
1339
8.02k
    const FunctionProtoType *CallOpProto, CallingConv CC) {
1340
8.02k
  const FunctionProtoType::ExtProtoInfo CallOpExtInfo =
1341
8.02k
      CallOpProto->getExtProtoInfo();
1342
8.02k
  FunctionProtoType::ExtProtoInfo InvokerExtInfo = CallOpExtInfo;
1343
8.02k
  InvokerExtInfo.ExtInfo = InvokerExtInfo.ExtInfo.withCallingConv(CC);
1344
8.02k
  InvokerExtInfo.TypeQuals = Qualifiers();
1345
8.02k
  assert(InvokerExtInfo.RefQualifier == RQ_None &&
1346
8.02k
         "Lambda's call operator should not have a reference qualifier");
1347
0
  return Context.getFunctionType(CallOpProto->getReturnType(),
1348
8.02k
                                 CallOpProto->getParamTypes(), InvokerExtInfo);
1349
8.02k
}
1350
1351
/// Add a lambda's conversion to function pointer, as described in
1352
/// C++11 [expr.prim.lambda]p6.
1353
static void addFunctionPointerConversion(Sema &S, SourceRange IntroducerRange,
1354
                                         CXXRecordDecl *Class,
1355
                                         CXXMethodDecl *CallOperator,
1356
7.46k
                                         QualType InvokerFunctionTy) {
1357
  // This conversion is explicitly disabled if the lambda's function has
1358
  // pass_object_size attributes on any of its parameters.
1359
7.46k
  auto HasPassObjectSizeAttr = [](const ParmVarDecl *P) {
1360
7.28k
    return P->hasAttr<PassObjectSizeAttr>();
1361
7.28k
  };
1362
7.46k
  if (llvm::any_of(CallOperator->parameters(), HasPassObjectSizeAttr))
1363
2
    return;
1364
1365
  // Add the conversion to function pointer.
1366
7.46k
  QualType PtrToFunctionTy = S.Context.getPointerType(InvokerFunctionTy);
1367
1368
  // Create the type of the conversion function.
1369
7.46k
  FunctionProtoType::ExtProtoInfo ConvExtInfo(
1370
7.46k
      S.Context.getDefaultCallingConvention(
1371
7.46k
      /*IsVariadic=*/false, /*IsCXXMethod=*/true));
1372
  // The conversion function is always const and noexcept.
1373
7.46k
  ConvExtInfo.TypeQuals = Qualifiers();
1374
7.46k
  ConvExtInfo.TypeQuals.addConst();
1375
7.46k
  ConvExtInfo.ExceptionSpec.Type = EST_BasicNoexcept;
1376
7.46k
  QualType ConvTy =
1377
7.46k
      S.Context.getFunctionType(PtrToFunctionTy, None, ConvExtInfo);
1378
1379
7.46k
  SourceLocation Loc = IntroducerRange.getBegin();
1380
7.46k
  DeclarationName ConversionName
1381
7.46k
    = S.Context.DeclarationNames.getCXXConversionFunctionName(
1382
7.46k
        S.Context.getCanonicalType(PtrToFunctionTy));
1383
  // Construct a TypeSourceInfo for the conversion function, and wire
1384
  // all the parameters appropriately for the FunctionProtoTypeLoc
1385
  // so that everything works during transformation/instantiation of
1386
  // generic lambdas.
1387
  // The main reason for wiring up the parameters of the conversion
1388
  // function with that of the call operator is so that constructs
1389
  // like the following work:
1390
  // auto L = [](auto b) {                <-- 1
1391
  //   return [](auto a) -> decltype(a) { <-- 2
1392
  //      return a;
1393
  //   };
1394
  // };
1395
  // int (*fp)(int) = L(5);
1396
  // Because the trailing return type can contain DeclRefExprs that refer
1397
  // to the original call operator's variables, we hijack the call
1398
  // operators ParmVarDecls below.
1399
7.46k
  TypeSourceInfo *ConvNamePtrToFunctionTSI =
1400
7.46k
      S.Context.getTrivialTypeSourceInfo(PtrToFunctionTy, Loc);
1401
7.46k
  DeclarationNameLoc ConvNameLoc =
1402
7.46k
      DeclarationNameLoc::makeNamedTypeLoc(ConvNamePtrToFunctionTSI);
1403
1404
  // The conversion function is a conversion to a pointer-to-function.
1405
7.46k
  TypeSourceInfo *ConvTSI = S.Context.getTrivialTypeSourceInfo(ConvTy, Loc);
1406
7.46k
  FunctionProtoTypeLoc ConvTL =
1407
7.46k
      ConvTSI->getTypeLoc().getAs<FunctionProtoTypeLoc>();
1408
  // Get the result of the conversion function which is a pointer-to-function.
1409
7.46k
  PointerTypeLoc PtrToFunctionTL =
1410
7.46k
      ConvTL.getReturnLoc().getAs<PointerTypeLoc>();
1411
  // Do the same for the TypeSourceInfo that is used to name the conversion
1412
  // operator.
1413
7.46k
  PointerTypeLoc ConvNamePtrToFunctionTL =
1414
7.46k
      ConvNamePtrToFunctionTSI->getTypeLoc().getAs<PointerTypeLoc>();
1415
1416
  // Get the underlying function types that the conversion function will
1417
  // be converting to (should match the type of the call operator).
1418
7.46k
  FunctionProtoTypeLoc CallOpConvTL =
1419
7.46k
      PtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();
1420
7.46k
  FunctionProtoTypeLoc CallOpConvNameTL =
1421
7.46k
    ConvNamePtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();
1422
1423
  // Wire up the FunctionProtoTypeLocs with the call operator's parameters.
1424
  // These parameter's are essentially used to transform the name and
1425
  // the type of the conversion operator.  By using the same parameters
1426
  // as the call operator's we don't have to fix any back references that
1427
  // the trailing return type of the call operator's uses (such as
1428
  // decltype(some_type<decltype(a)>::type{} + decltype(a){}) etc.)
1429
  // - we can simply use the return type of the call operator, and
1430
  // everything should work.
1431
7.46k
  SmallVector<ParmVarDecl *, 4> InvokerParams;
1432
14.7k
  for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; 
++I7.28k
) {
1433
7.28k
    ParmVarDecl *From = CallOperator->getParamDecl(I);
1434
1435
7.28k
    InvokerParams.push_back(ParmVarDecl::Create(
1436
7.28k
        S.Context,
1437
        // Temporarily add to the TU. This is set to the invoker below.
1438
7.28k
        S.Context.getTranslationUnitDecl(), From->getBeginLoc(),
1439
7.28k
        From->getLocation(), From->getIdentifier(), From->getType(),
1440
7.28k
        From->getTypeSourceInfo(), From->getStorageClass(),
1441
7.28k
        /*DefArg=*/nullptr));
1442
7.28k
    CallOpConvTL.setParam(I, From);
1443
7.28k
    CallOpConvNameTL.setParam(I, From);
1444
7.28k
  }
1445
1446
7.46k
  CXXConversionDecl *Conversion = CXXConversionDecl::Create(
1447
7.46k
      S.Context, Class, Loc,
1448
7.46k
      DeclarationNameInfo(ConversionName, Loc, ConvNameLoc), ConvTy, ConvTSI,
1449
7.46k
      S.getCurFPFeatures().isFPConstrained(),
1450
7.46k
      /*isInline=*/true, ExplicitSpecifier(),
1451
7.46k
      S.getLangOpts().CPlusPlus17 ? 
ConstexprSpecKind::Constexpr1.67k
1452
7.46k
                                  : 
ConstexprSpecKind::Unspecified5.79k
,
1453
7.46k
      CallOperator->getBody()->getEndLoc());
1454
7.46k
  Conversion->setAccess(AS_public);
1455
7.46k
  Conversion->setImplicit(true);
1456
1457
7.46k
  if (Class->isGenericLambda()) {
1458
    // Create a template version of the conversion operator, using the template
1459
    // parameter list of the function call operator.
1460
3.79k
    FunctionTemplateDecl *TemplateCallOperator =
1461
3.79k
            CallOperator->getDescribedFunctionTemplate();
1462
3.79k
    FunctionTemplateDecl *ConversionTemplate =
1463
3.79k
                  FunctionTemplateDecl::Create(S.Context, Class,
1464
3.79k
                                      Loc, ConversionName,
1465
3.79k
                                      TemplateCallOperator->getTemplateParameters(),
1466
3.79k
                                      Conversion);
1467
3.79k
    ConversionTemplate->setAccess(AS_public);
1468
3.79k
    ConversionTemplate->setImplicit(true);
1469
3.79k
    Conversion->setDescribedFunctionTemplate(ConversionTemplate);
1470
3.79k
    Class->addDecl(ConversionTemplate);
1471
3.79k
  } else
1472
3.67k
    Class->addDecl(Conversion);
1473
  // Add a non-static member function that will be the result of
1474
  // the conversion with a certain unique ID.
1475
7.46k
  DeclarationName InvokerName = &S.Context.Idents.get(
1476
7.46k
                                                 getLambdaStaticInvokerName());
1477
  // FIXME: Instead of passing in the CallOperator->getTypeSourceInfo()
1478
  // we should get a prebuilt TrivialTypeSourceInfo from Context
1479
  // using FunctionTy & Loc and get its TypeLoc as a FunctionProtoTypeLoc
1480
  // then rewire the parameters accordingly, by hoisting up the InvokeParams
1481
  // loop below and then use its Params to set Invoke->setParams(...) below.
1482
  // This would avoid the 'const' qualifier of the calloperator from
1483
  // contaminating the type of the invoker, which is currently adjusted
1484
  // in SemaTemplateDeduction.cpp:DeduceTemplateArguments.  Fixing the
1485
  // trailing return type of the invoker would require a visitor to rebuild
1486
  // the trailing return type and adjusting all back DeclRefExpr's to refer
1487
  // to the new static invoker parameters - not the call operator's.
1488
7.46k
  CXXMethodDecl *Invoke = CXXMethodDecl::Create(
1489
7.46k
      S.Context, Class, Loc, DeclarationNameInfo(InvokerName, Loc),
1490
7.46k
      InvokerFunctionTy, CallOperator->getTypeSourceInfo(), SC_Static,
1491
7.46k
      S.getCurFPFeatures().isFPConstrained(),
1492
7.46k
      /*isInline=*/true, ConstexprSpecKind::Unspecified,
1493
7.46k
      CallOperator->getBody()->getEndLoc());
1494
14.7k
  for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; 
++I7.28k
)
1495
7.28k
    InvokerParams[I]->setOwningFunction(Invoke);
1496
7.46k
  Invoke->setParams(InvokerParams);
1497
7.46k
  Invoke->setAccess(AS_private);
1498
7.46k
  Invoke->setImplicit(true);
1499
7.46k
  if (Class->isGenericLambda()) {
1500
3.79k
    FunctionTemplateDecl *TemplateCallOperator =
1501
3.79k
            CallOperator->getDescribedFunctionTemplate();
1502
3.79k
    FunctionTemplateDecl *StaticInvokerTemplate = FunctionTemplateDecl::Create(
1503
3.79k
                          S.Context, Class, Loc, InvokerName,
1504
3.79k
                          TemplateCallOperator->getTemplateParameters(),
1505
3.79k
                          Invoke);
1506
3.79k
    StaticInvokerTemplate->setAccess(AS_private);
1507
3.79k
    StaticInvokerTemplate->setImplicit(true);
1508
3.79k
    Invoke->setDescribedFunctionTemplate(StaticInvokerTemplate);
1509
3.79k
    Class->addDecl(StaticInvokerTemplate);
1510
3.79k
  } else
1511
3.67k
    Class->addDecl(Invoke);
1512
7.46k
}
1513
1514
/// Add a lambda's conversion to function pointers, as described in
1515
/// C++11 [expr.prim.lambda]p6. Note that in most cases, this should emit only a
1516
/// single pointer conversion. In the event that the default calling convention
1517
/// for free and member functions is different, it will emit both conventions.
1518
static void addFunctionPointerConversions(Sema &S, SourceRange IntroducerRange,
1519
                                          CXXRecordDecl *Class,
1520
5.77k
                                          CXXMethodDecl *CallOperator) {
1521
5.77k
  const FunctionProtoType *CallOpProto =
1522
5.77k
      CallOperator->getType()->castAs<FunctionProtoType>();
1523
1524
5.77k
  repeatForLambdaConversionFunctionCallingConvs(
1525
7.46k
      S, *CallOpProto, [&](CallingConv CC) {
1526
7.46k
        QualType InvokerFunctionTy =
1527
7.46k
            S.getLambdaConversionFunctionResultType(CallOpProto, CC);
1528
7.46k
        addFunctionPointerConversion(S, IntroducerRange, Class, CallOperator,
1529
7.46k
                                     InvokerFunctionTy);
1530
7.46k
      });
1531
5.77k
}
1532
1533
/// Add a lambda's conversion to block pointer.
1534
static void addBlockPointerConversion(Sema &S,
1535
                                      SourceRange IntroducerRange,
1536
                                      CXXRecordDecl *Class,
1537
162
                                      CXXMethodDecl *CallOperator) {
1538
162
  const FunctionProtoType *CallOpProto =
1539
162
      CallOperator->getType()->castAs<FunctionProtoType>();
1540
162
  QualType FunctionTy = S.getLambdaConversionFunctionResultType(
1541
162
      CallOpProto, getLambdaConversionFunctionCallConv(S, CallOpProto));
1542
162
  QualType BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);
1543
1544
162
  FunctionProtoType::ExtProtoInfo ConversionEPI(
1545
162
      S.Context.getDefaultCallingConvention(
1546
162
          /*IsVariadic=*/false, /*IsCXXMethod=*/true));
1547
162
  ConversionEPI.TypeQuals = Qualifiers();
1548
162
  ConversionEPI.TypeQuals.addConst();
1549
162
  QualType ConvTy = S.Context.getFunctionType(BlockPtrTy, None, ConversionEPI);
1550
1551
162
  SourceLocation Loc = IntroducerRange.getBegin();
1552
162
  DeclarationName Name
1553
162
    = S.Context.DeclarationNames.getCXXConversionFunctionName(
1554
162
        S.Context.getCanonicalType(BlockPtrTy));
1555
162
  DeclarationNameLoc NameLoc = DeclarationNameLoc::makeNamedTypeLoc(
1556
162
      S.Context.getTrivialTypeSourceInfo(BlockPtrTy, Loc));
1557
162
  CXXConversionDecl *Conversion = CXXConversionDecl::Create(
1558
162
      S.Context, Class, Loc, DeclarationNameInfo(Name, Loc, NameLoc), ConvTy,
1559
162
      S.Context.getTrivialTypeSourceInfo(ConvTy, Loc),
1560
162
      S.getCurFPFeatures().isFPConstrained(),
1561
162
      /*isInline=*/true, ExplicitSpecifier(), ConstexprSpecKind::Unspecified,
1562
162
      CallOperator->getBody()->getEndLoc());
1563
162
  Conversion->setAccess(AS_public);
1564
162
  Conversion->setImplicit(true);
1565
162
  Class->addDecl(Conversion);
1566
162
}
1567
1568
ExprResult Sema::BuildCaptureInit(const Capture &Cap,
1569
                                  SourceLocation ImplicitCaptureLoc,
1570
399k
                                  bool IsOpenMPMapping) {
1571
  // VLA captures don't have a stored initialization expression.
1572
399k
  if (Cap.isVLATypeCapture())
1573
8.94k
    return ExprResult();
1574
1575
  // An init-capture is initialized directly from its stored initializer.
1576
390k
  if (Cap.isInitCapture())
1577
533
    return Cap.getVariable()->getInit();
1578
1579
  // For anything else, build an initialization expression. For an implicit
1580
  // capture, the capture notionally happens at the capture-default, so use
1581
  // that location here.
1582
390k
  SourceLocation Loc =
1583
390k
      ImplicitCaptureLoc.isValid() ? 
ImplicitCaptureLoc388k
:
Cap.getLocation()1.54k
;
1584
1585
  // C++11 [expr.prim.lambda]p21:
1586
  //   When the lambda-expression is evaluated, the entities that
1587
  //   are captured by copy are used to direct-initialize each
1588
  //   corresponding non-static data member of the resulting closure
1589
  //   object. (For array members, the array elements are
1590
  //   direct-initialized in increasing subscript order.) These
1591
  //   initializations are performed in the (unspecified) order in
1592
  //   which the non-static data members are declared.
1593
1594
  // C++ [expr.prim.lambda]p12:
1595
  //   An entity captured by a lambda-expression is odr-used (3.2) in
1596
  //   the scope containing the lambda-expression.
1597
390k
  ExprResult Init;
1598
390k
  IdentifierInfo *Name = nullptr;
1599
390k
  if (Cap.isThisCapture()) {
1600
11.3k
    QualType ThisTy = getCurrentThisType();
1601
11.3k
    Expr *This = BuildCXXThisExpr(Loc, ThisTy, ImplicitCaptureLoc.isValid());
1602
11.3k
    if (Cap.isCopyCapture())
1603
137
      Init = CreateBuiltinUnaryOp(Loc, UO_Deref, This);
1604
11.1k
    else
1605
11.1k
      Init = This;
1606
379k
  } else {
1607
379k
    assert(Cap.isVariableCapture() && "unknown kind of capture");
1608
0
    VarDecl *Var = Cap.getVariable();
1609
379k
    Name = Var->getIdentifier();
1610
379k
    Init = BuildDeclarationNameExpr(
1611
379k
      CXXScopeSpec(), DeclarationNameInfo(Var->getDeclName(), Loc), Var);
1612
379k
  }
1613
1614
  // In OpenMP, the capture kind doesn't actually describe how to capture:
1615
  // variables are "mapped" onto the device in a process that does not formally
1616
  // make a copy, even for a "copy capture".
1617
390k
  if (IsOpenMPMapping)
1618
384k
    return Init;
1619
1620
5.68k
  if (Init.isInvalid())
1621
0
    return ExprError();
1622
1623
5.68k
  Expr *InitExpr = Init.get();
1624
5.68k
  InitializedEntity Entity = InitializedEntity::InitializeLambdaCapture(
1625
5.68k
      Name, Cap.getCaptureType(), Loc);
1626
5.68k
  InitializationKind InitKind =
1627
5.68k
      InitializationKind::CreateDirect(Loc, Loc, Loc);
1628
5.68k
  InitializationSequence InitSeq(*this, Entity, InitKind, InitExpr);
1629
5.68k
  return InitSeq.Perform(*this, Entity, InitKind, InitExpr);
1630
5.68k
}
1631
1632
ExprResult Sema::ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
1633
8.11k
                                 Scope *CurScope) {
1634
8.11k
  LambdaScopeInfo LSI = *cast<LambdaScopeInfo>(FunctionScopes.back());
1635
8.11k
  ActOnFinishFunctionBody(LSI.CallOperator, Body);
1636
8.11k
  return BuildLambdaExpr(StartLoc, Body->getEndLoc(), &LSI);
1637
8.11k
}
1638
1639
static LambdaCaptureDefault
1640
10.6k
mapImplicitCaptureStyle(CapturingScopeInfo::ImplicitCaptureStyle ICS) {
1641
10.6k
  switch (ICS) {
1642
7.32k
  case CapturingScopeInfo::ImpCap_None:
1643
7.32k
    return LCD_None;
1644
1.30k
  case CapturingScopeInfo::ImpCap_LambdaByval:
1645
1.30k
    return LCD_ByCopy;
1646
0
  case CapturingScopeInfo::ImpCap_CapturedRegion:
1647
2.05k
  case CapturingScopeInfo::ImpCap_LambdaByref:
1648
2.05k
    return LCD_ByRef;
1649
0
  case CapturingScopeInfo::ImpCap_Block:
1650
0
    llvm_unreachable("block capture in lambda");
1651
10.6k
  }
1652
0
  llvm_unreachable("Unknown implicit capture style");
1653
0
}
1654
1655
718
bool Sema::CaptureHasSideEffects(const Capture &From) {
1656
718
  if (From.isInitCapture()) {
1657
211
    Expr *Init = From.getVariable()->getInit();
1658
211
    if (Init && Init->HasSideEffects(Context))
1659
54
      return true;
1660
211
  }
1661
1662
664
  if (!From.isCopyCapture())
1663
169
    return false;
1664
1665
495
  const QualType T = From.isThisCapture()
1666
495
                         ? 
getCurrentThisType()->getPointeeType()42
1667
495
                         : 
From.getCaptureType()453
;
1668
1669
495
  if (T.isVolatileQualified())
1670
2
    return true;
1671
1672
493
  const Type *BaseT = T->getBaseElementTypeUnsafe();
1673
493
  if (const CXXRecordDecl *RD = BaseT->getAsCXXRecordDecl())
1674
102
    return !RD->isCompleteDefinition() || !RD->hasTrivialCopyConstructor() ||
1675
102
           
!RD->hasTrivialDestructor()70
;
1676
1677
391
  return false;
1678
493
}
1679
1680
bool Sema::DiagnoseUnusedLambdaCapture(SourceRange CaptureRange,
1681
718
                                       const Capture &From) {
1682
718
  if (CaptureHasSideEffects(From))
1683
95
    return false;
1684
1685
623
  if (From.isVLATypeCapture())
1686
22
    return false;
1687
1688
601
  auto diag = Diag(From.getLocation(), diag::warn_unused_lambda_capture);
1689
601
  if (From.isThisCapture())
1690
85
    diag << "'this'";
1691
516
  else
1692
516
    diag << From.getVariable();
1693
601
  diag << From.isNonODRUsed();
1694
601
  diag << FixItHint::CreateRemoval(CaptureRange);
1695
601
  return true;
1696
623
}
1697
1698
/// Create a field within the lambda class or captured statement record for the
1699
/// given capture.
1700
FieldDecl *Sema::BuildCaptureField(RecordDecl *RD,
1701
399k
                                   const sema::Capture &Capture) {
1702
399k
  SourceLocation Loc = Capture.getLocation();
1703
399k
  QualType FieldType = Capture.getCaptureType();
1704
1705
399k
  TypeSourceInfo *TSI = nullptr;
1706
399k
  if (Capture.isVariableCapture()) {
1707
379k
    auto *Var = Capture.getVariable();
1708
379k
    if (Var->isInitCapture())
1709
580
      TSI = Capture.getVariable()->getTypeSourceInfo();
1710
379k
  }
1711
1712
  // FIXME: Should we really be doing this? A null TypeSourceInfo seems more
1713
  // appropriate, at least for an implicit capture.
1714
399k
  if (!TSI)
1715
399k
    TSI = Context.getTrivialTypeSourceInfo(FieldType, Loc);
1716
1717
  // Build the non-static data member.
1718
399k
  FieldDecl *Field =
1719
399k
      FieldDecl::Create(Context, RD, /*StartLoc=*/Loc, /*IdLoc=*/Loc,
1720
399k
                        /*Id=*/nullptr, FieldType, TSI, /*BW=*/nullptr,
1721
399k
                        /*Mutable=*/false, ICIS_NoInit);
1722
  // If the variable being captured has an invalid type, mark the class as
1723
  // invalid as well.
1724
399k
  if (!FieldType->isDependentType()) {
1725
395k
    if (RequireCompleteSizedType(Loc, FieldType,
1726
395k
                                 diag::err_field_incomplete_or_sizeless)) {
1727
3
      RD->setInvalidDecl();
1728
3
      Field->setInvalidDecl();
1729
395k
    } else {
1730
395k
      NamedDecl *Def;
1731
395k
      FieldType->isIncompleteType(&Def);
1732
395k
      if (Def && 
Def->isInvalidDecl()308
) {
1733
2
        RD->setInvalidDecl();
1734
2
        Field->setInvalidDecl();
1735
2
      }
1736
395k
    }
1737
395k
  }
1738
399k
  Field->setImplicit(true);
1739
399k
  Field->setAccess(AS_private);
1740
399k
  RD->addDecl(Field);
1741
1742
399k
  if (Capture.isVLATypeCapture())
1743
8.94k
    Field->setCapturedVLAType(Capture.getCapturedVLAType());
1744
1745
399k
  return Field;
1746
399k
}
1747
1748
ExprResult Sema::BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
1749
10.6k
                                 LambdaScopeInfo *LSI) {
1750
  // Collect information from the lambda scope.
1751
10.6k
  SmallVector<LambdaCapture, 4> Captures;
1752
10.6k
  SmallVector<Expr *, 4> CaptureInits;
1753
10.6k
  SourceLocation CaptureDefaultLoc = LSI->CaptureDefaultLoc;
1754
10.6k
  LambdaCaptureDefault CaptureDefault =
1755
10.6k
      mapImplicitCaptureStyle(LSI->ImpCaptureStyle);
1756
10.6k
  CXXRecordDecl *Class;
1757
10.6k
  CXXMethodDecl *CallOperator;
1758
10.6k
  SourceRange IntroducerRange;
1759
10.6k
  bool ExplicitParams;
1760
10.6k
  bool ExplicitResultType;
1761
10.6k
  CleanupInfo LambdaCleanup;
1762
10.6k
  bool ContainsUnexpandedParameterPack;
1763
10.6k
  bool IsGenericLambda;
1764
10.6k
  {
1765
10.6k
    CallOperator = LSI->CallOperator;
1766
10.6k
    Class = LSI->Lambda;
1767
10.6k
    IntroducerRange = LSI->IntroducerRange;
1768
10.6k
    ExplicitParams = LSI->ExplicitParams;
1769
10.6k
    ExplicitResultType = !LSI->HasImplicitReturnType;
1770
10.6k
    LambdaCleanup = LSI->Cleanup;
1771
10.6k
    ContainsUnexpandedParameterPack = LSI->ContainsUnexpandedParameterPack;
1772
10.6k
    IsGenericLambda = Class->isGenericLambda();
1773
1774
10.6k
    CallOperator->setLexicalDeclContext(Class);
1775
10.6k
    Decl *TemplateOrNonTemplateCallOperatorDecl =
1776
10.6k
        CallOperator->getDescribedFunctionTemplate()
1777
10.6k
        ? 
CallOperator->getDescribedFunctionTemplate()3.60k
1778
10.6k
        : 
cast<Decl>(CallOperator)7.07k
;
1779
1780
    // FIXME: Is this really the best choice? Keeping the lexical decl context
1781
    // set as CurContext seems more faithful to the source.
1782
10.6k
    TemplateOrNonTemplateCallOperatorDecl->setLexicalDeclContext(Class);
1783
1784
10.6k
    PopExpressionEvaluationContext();
1785
1786
    // True if the current capture has a used capture or default before it.
1787
10.6k
    bool CurHasPreviousCapture = CaptureDefault != LCD_None;
1788
10.6k
    SourceLocation PrevCaptureLoc = CurHasPreviousCapture ?
1789
7.32k
        
CaptureDefaultLoc3.35k
: IntroducerRange.getBegin();
1790
1791
16.6k
    for (unsigned I = 0, N = LSI->Captures.size(); I != N; 
++I5.97k
) {
1792
5.99k
      const Capture &From = LSI->Captures[I];
1793
1794
5.99k
      if (From.isInvalid())
1795
24
        return ExprError();
1796
1797
5.97k
      assert(!From.isBlockCapture() && "Cannot capture __block variables");
1798
0
      bool IsImplicit = I >= LSI->NumExplicitCaptures;
1799
5.97k
      SourceLocation ImplicitCaptureLoc =
1800
5.97k
          IsImplicit ? 
CaptureDefaultLoc3.96k
:
SourceLocation()2.01k
;
1801
1802
      // Use source ranges of explicit captures for fixits where available.
1803
5.97k
      SourceRange CaptureRange = LSI->ExplicitCaptureRanges[I];
1804
1805
      // Warn about unused explicit captures.
1806
5.97k
      bool IsCaptureUsed = true;
1807
5.97k
      if (!CurContext->isDependentContext() && 
!IsImplicit5.40k
&&
1808
5.97k
          
!From.isODRUsed()1.57k
) {
1809
        // Initialized captures that are non-ODR used may not be eliminated.
1810
        // FIXME: Where did the IsGenericLambda here come from?
1811
729
        bool NonODRUsedInitCapture =
1812
729
            IsGenericLambda && 
From.isNonODRUsed()39
&&
From.isInitCapture()12
;
1813
729
        if (!NonODRUsedInitCapture) {
1814
718
          bool IsLast = (I + 1) == LSI->NumExplicitCaptures;
1815
718
          SourceRange FixItRange;
1816
718
          if (CaptureRange.isValid()) {
1817
551
            if (!CurHasPreviousCapture && 
!IsLast483
) {
1818
              // If there are no captures preceding this capture, remove the
1819
              // following comma.
1820
97
              FixItRange = SourceRange(CaptureRange.getBegin(),
1821
97
                                       getLocForEndOfToken(CaptureRange.getEnd()));
1822
454
            } else {
1823
              // Otherwise, remove the comma since the last used capture.
1824
454
              FixItRange = SourceRange(getLocForEndOfToken(PrevCaptureLoc),
1825
454
                                       CaptureRange.getEnd());
1826
454
            }
1827
551
          }
1828
1829
718
          IsCaptureUsed = !DiagnoseUnusedLambdaCapture(FixItRange, From);
1830
718
        }
1831
729
      }
1832
1833
5.97k
      if (CaptureRange.isValid()) {
1834
1.58k
        CurHasPreviousCapture |= IsCaptureUsed;
1835
1.58k
        PrevCaptureLoc = CaptureRange.getEnd();
1836
1.58k
      }
1837
1838
      // Map the capture to our AST representation.
1839
5.97k
      LambdaCapture Capture = [&] {
1840
5.97k
        if (From.isThisCapture()) {
1841
          // Capturing 'this' implicitly with a default of '[=]' is deprecated,
1842
          // because it results in a reference capture. Don't warn prior to
1843
          // C++2a; there's nothing that can be done about it before then.
1844
829
          if (getLangOpts().CPlusPlus20 && 
IsImplicit76
&&
1845
829
              
CaptureDefault == LCD_ByCopy48
) {
1846
41
            Diag(From.getLocation(), diag::warn_deprecated_this_capture);
1847
41
            Diag(CaptureDefaultLoc, diag::note_deprecated_this_capture)
1848
41
                << FixItHint::CreateInsertion(
1849
41
                       getLocForEndOfToken(CaptureDefaultLoc), ", this");
1850
41
          }
1851
829
          return LambdaCapture(From.getLocation(), IsImplicit,
1852
829
                               From.isCopyCapture() ? 
LCK_StarThis137
:
LCK_This692
);
1853
5.14k
        } else if (From.isVLATypeCapture()) {
1854
50
          return LambdaCapture(From.getLocation(), IsImplicit, LCK_VLAType);
1855
5.09k
        } else {
1856
5.09k
          assert(From.isVariableCapture() && "unknown kind of capture");
1857
0
          VarDecl *Var = From.getVariable();
1858
5.09k
          LambdaCaptureKind Kind =
1859
5.09k
              From.isCopyCapture() ? 
LCK_ByCopy1.84k
:
LCK_ByRef3.25k
;
1860
5.09k
          return LambdaCapture(From.getLocation(), IsImplicit, Kind, Var,
1861
5.09k
                               From.getEllipsisLoc());
1862
5.09k
        }
1863
5.97k
      }();
1864
1865
      // Form the initializer for the capture field.
1866
5.97k
      ExprResult Init = BuildCaptureInit(From, ImplicitCaptureLoc);
1867
1868
      // FIXME: Skip this capture if the capture is not used, the initializer
1869
      // has no side-effects, the type of the capture is trivial, and the
1870
      // lambda is not externally visible.
1871
1872
      // Add a FieldDecl for the capture and form its initializer.
1873
5.97k
      BuildCaptureField(Class, From);
1874
5.97k
      Captures.push_back(Capture);
1875
5.97k
      CaptureInits.push_back(Init.get());
1876
1877
5.97k
      if (LangOpts.CUDA)
1878
98
        CUDACheckLambdaCapture(CallOperator, From);
1879
5.97k
    }
1880
1881
10.6k
    Class->setCaptures(Context, Captures);
1882
1883
    // C++11 [expr.prim.lambda]p6:
1884
    //   The closure type for a lambda-expression with no lambda-capture
1885
    //   has a public non-virtual non-explicit const conversion function
1886
    //   to pointer to function having the same parameter and return
1887
    //   types as the closure type's function call operator.
1888
10.6k
    if (Captures.empty() && 
CaptureDefault == LCD_None6.91k
)
1889
5.77k
      addFunctionPointerConversions(*this, IntroducerRange, Class,
1890
5.77k
                                    CallOperator);
1891
1892
    // Objective-C++:
1893
    //   The closure type for a lambda-expression has a public non-virtual
1894
    //   non-explicit const conversion function to a block pointer having the
1895
    //   same parameter and return types as the closure type's function call
1896
    //   operator.
1897
    // FIXME: Fix generic lambda to block conversions.
1898
10.6k
    if (getLangOpts().Blocks && 
getLangOpts().ObjC5.63k
&&
!IsGenericLambda171
)
1899
162
      addBlockPointerConversion(*this, IntroducerRange, Class, CallOperator);
1900
1901
    // Finalize the lambda class.
1902
10.6k
    SmallVector<Decl*, 4> Fields(Class->fields());
1903
10.6k
    ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
1904
10.6k
                SourceLocation(), ParsedAttributesView());
1905
10.6k
    CheckCompletedCXXClass(nullptr, Class);
1906
10.6k
  }
1907
1908
0
  Cleanup.mergeFrom(LambdaCleanup);
1909
1910
10.6k
  LambdaExpr *Lambda = LambdaExpr::Create(Context, Class, IntroducerRange,
1911
10.6k
                                          CaptureDefault, CaptureDefaultLoc,
1912
10.6k
                                          ExplicitParams, ExplicitResultType,
1913
10.6k
                                          CaptureInits, EndLoc,
1914
10.6k
                                          ContainsUnexpandedParameterPack);
1915
  // If the lambda expression's call operator is not explicitly marked constexpr
1916
  // and we are not in a dependent context, analyze the call operator to infer
1917
  // its constexpr-ness, suppressing diagnostics while doing so.
1918
10.6k
  if (getLangOpts().CPlusPlus17 && 
!CallOperator->isInvalidDecl()3.16k
&&
1919
10.6k
      
!CallOperator->isConstexpr()3.13k
&&
1920
10.6k
      
!isa<CoroutineBodyStmt>(CallOperator->getBody())2.97k
&&
1921
10.6k
      
!Class->getDeclContext()->isDependentContext()2.92k
) {
1922
2.13k
    CallOperator->setConstexprKind(
1923
2.13k
        CheckConstexprFunctionDefinition(CallOperator,
1924
2.13k
                                         CheckConstexprKind::CheckValid)
1925
2.13k
            ? 
ConstexprSpecKind::Constexpr2.08k
1926
2.13k
            : 
ConstexprSpecKind::Unspecified46
);
1927
2.13k
  }
1928
1929
  // Emit delayed shadowing warnings now that the full capture list is known.
1930
10.6k
  DiagnoseShadowingLambdaDecls(LSI);
1931
1932
10.6k
  if (!CurContext->isDependentContext()) {
1933
8.12k
    switch (ExprEvalContexts.back().Context) {
1934
    // C++11 [expr.prim.lambda]p2:
1935
    //   A lambda-expression shall not appear in an unevaluated operand
1936
    //   (Clause 5).
1937
39
    case ExpressionEvaluationContext::Unevaluated:
1938
39
    case ExpressionEvaluationContext::UnevaluatedList:
1939
39
    case ExpressionEvaluationContext::UnevaluatedAbstract:
1940
    // C++1y [expr.const]p2:
1941
    //   A conditional-expression e is a core constant expression unless the
1942
    //   evaluation of e, following the rules of the abstract machine, would
1943
    //   evaluate [...] a lambda-expression.
1944
    //
1945
    // This is technically incorrect, there are some constant evaluated contexts
1946
    // where this should be allowed.  We should probably fix this when DR1607 is
1947
    // ratified, it lays out the exact set of conditions where we shouldn't
1948
    // allow a lambda-expression.
1949
220
    case ExpressionEvaluationContext::ConstantEvaluated:
1950
220
    case ExpressionEvaluationContext::ImmediateFunctionContext:
1951
      // We don't actually diagnose this case immediately, because we
1952
      // could be within a context where we might find out later that
1953
      // the expression is potentially evaluated (e.g., for typeid).
1954
220
      ExprEvalContexts.back().Lambdas.push_back(Lambda);
1955
220
      break;
1956
1957
0
    case ExpressionEvaluationContext::DiscardedStatement:
1958
7.62k
    case ExpressionEvaluationContext::PotentiallyEvaluated:
1959
7.90k
    case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
1960
7.90k
      break;
1961
8.12k
    }
1962
8.12k
  }
1963
1964
10.6k
  return MaybeBindToTemporary(Lambda);
1965
10.6k
}
1966
1967
ExprResult Sema::BuildBlockForLambdaConversion(SourceLocation CurrentLocation,
1968
                                               SourceLocation ConvLocation,
1969
                                               CXXConversionDecl *Conv,
1970
31
                                               Expr *Src) {
1971
  // Make sure that the lambda call operator is marked used.
1972
31
  CXXRecordDecl *Lambda = Conv->getParent();
1973
31
  CXXMethodDecl *CallOperator
1974
31
    = cast<CXXMethodDecl>(
1975
31
        Lambda->lookup(
1976
31
          Context.DeclarationNames.getCXXOperatorName(OO_Call)).front());
1977
31
  CallOperator->setReferenced();
1978
31
  CallOperator->markUsed(Context);
1979
1980
31
  ExprResult Init = PerformCopyInitialization(
1981
31
      InitializedEntity::InitializeLambdaToBlock(ConvLocation, Src->getType()),
1982
31
      CurrentLocation, Src);
1983
31
  if (!Init.isInvalid())
1984
31
    Init = ActOnFinishFullExpr(Init.get(), /*DiscardedValue*/ false);
1985
1986
31
  if (Init.isInvalid())
1987
0
    return ExprError();
1988
1989
  // Create the new block to be returned.
1990
31
  BlockDecl *Block = BlockDecl::Create(Context, CurContext, ConvLocation);
1991
1992
  // Set the type information.
1993
31
  Block->setSignatureAsWritten(CallOperator->getTypeSourceInfo());
1994
31
  Block->setIsVariadic(CallOperator->isVariadic());
1995
31
  Block->setBlockMissingReturnType(false);
1996
1997
  // Add parameters.
1998
31
  SmallVector<ParmVarDecl *, 4> BlockParams;
1999
42
  for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; 
++I11
) {
2000
11
    ParmVarDecl *From = CallOperator->getParamDecl(I);
2001
11
    BlockParams.push_back(ParmVarDecl::Create(
2002
11
        Context, Block, From->getBeginLoc(), From->getLocation(),
2003
11
        From->getIdentifier(), From->getType(), From->getTypeSourceInfo(),
2004
11
        From->getStorageClass(),
2005
11
        /*DefArg=*/nullptr));
2006
11
  }
2007
31
  Block->setParams(BlockParams);
2008
2009
31
  Block->setIsConversionFromLambda(true);
2010
2011
  // Add capture. The capture uses a fake variable, which doesn't correspond
2012
  // to any actual memory location. However, the initializer copy-initializes
2013
  // the lambda object.
2014
31
  TypeSourceInfo *CapVarTSI =
2015
31
      Context.getTrivialTypeSourceInfo(Src->getType());
2016
31
  VarDecl *CapVar = VarDecl::Create(Context, Block, ConvLocation,
2017
31
                                    ConvLocation, nullptr,
2018
31
                                    Src->getType(), CapVarTSI,
2019
31
                                    SC_None);
2020
31
  BlockDecl::Capture Capture(/*variable=*/CapVar, /*byRef=*/false,
2021
31
                             /*nested=*/false, /*copy=*/Init.get());
2022
31
  Block->setCaptures(Context, Capture, /*CapturesCXXThis=*/false);
2023
2024
  // Add a fake function body to the block. IR generation is responsible
2025
  // for filling in the actual body, which cannot be expressed as an AST.
2026
31
  Block->setBody(new (Context) CompoundStmt(ConvLocation));
2027
2028
  // Create the block literal expression.
2029
31
  Expr *BuildBlock = new (Context) BlockExpr(Block, Conv->getConversionType());
2030
31
  ExprCleanupObjects.push_back(Block);
2031
31
  Cleanup.setExprNeedsCleanups(true);
2032
2033
31
  return BuildBlock;
2034
31
}