clang  7.0.0
SemaCast.cpp
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1 //===--- SemaCast.cpp - Semantic Analysis for Casts -----------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements semantic analysis for cast expressions, including
11 // 1) C-style casts like '(int) x'
12 // 2) C++ functional casts like 'int(x)'
13 // 3) C++ named casts like 'static_cast<int>(x)'
14 //
15 //===----------------------------------------------------------------------===//
16 
18 #include "clang/AST/ASTContext.h"
20 #include "clang/AST/ExprCXX.h"
21 #include "clang/AST/ExprObjC.h"
22 #include "clang/AST/RecordLayout.h"
24 #include "clang/Basic/TargetInfo.h"
25 #include "clang/Lex/Preprocessor.h"
27 #include "llvm/ADT/SmallVector.h"
28 #include <set>
29 using namespace clang;
30 
31 
32 
34  TC_NotApplicable, ///< The cast method is not applicable.
35  TC_Success, ///< The cast method is appropriate and successful.
36  TC_Extension, ///< The cast method is appropriate and accepted as a
37  ///< language extension.
38  TC_Failed ///< The cast method is appropriate, but failed. A
39  ///< diagnostic has been emitted.
40 };
41 
42 static bool isValidCast(TryCastResult TCR) {
43  return TCR == TC_Success || TCR == TC_Extension;
44 }
45 
46 enum CastType {
47  CT_Const, ///< const_cast
48  CT_Static, ///< static_cast
49  CT_Reinterpret, ///< reinterpret_cast
50  CT_Dynamic, ///< dynamic_cast
51  CT_CStyle, ///< (Type)expr
52  CT_Functional ///< Type(expr)
53 };
54 
55 namespace {
56  struct CastOperation {
57  CastOperation(Sema &S, QualType destType, ExprResult src)
58  : Self(S), SrcExpr(src), DestType(destType),
59  ResultType(destType.getNonLValueExprType(S.Context)),
60  ValueKind(Expr::getValueKindForType(destType)),
61  Kind(CK_Dependent), IsARCUnbridgedCast(false) {
62 
63  if (const BuiltinType *placeholder =
64  src.get()->getType()->getAsPlaceholderType()) {
65  PlaceholderKind = placeholder->getKind();
66  } else {
67  PlaceholderKind = (BuiltinType::Kind) 0;
68  }
69  }
70 
71  Sema &Self;
72  ExprResult SrcExpr;
73  QualType DestType;
74  QualType ResultType;
75  ExprValueKind ValueKind;
76  CastKind Kind;
77  BuiltinType::Kind PlaceholderKind;
78  CXXCastPath BasePath;
79  bool IsARCUnbridgedCast;
80 
81  SourceRange OpRange;
82  SourceRange DestRange;
83 
84  // Top-level semantics-checking routines.
85  void CheckConstCast();
86  void CheckReinterpretCast();
87  void CheckStaticCast();
88  void CheckDynamicCast();
89  void CheckCXXCStyleCast(bool FunctionalCast, bool ListInitialization);
90  void CheckCStyleCast();
91 
92  void updatePartOfExplicitCastFlags(CastExpr *CE) {
93  // Walk down from the CE to the OrigSrcExpr, and mark all immediate
94  // ImplicitCastExpr's as being part of ExplicitCastExpr. The original CE
95  // (which is a ExplicitCastExpr), and the OrigSrcExpr are not touched.
96  for (; auto *ICE = dyn_cast<ImplicitCastExpr>(CE->getSubExpr()); CE = ICE)
97  ICE->setIsPartOfExplicitCast(true);
98  }
99 
100  /// Complete an apparently-successful cast operation that yields
101  /// the given expression.
102  ExprResult complete(CastExpr *castExpr) {
103  // If this is an unbridged cast, wrap the result in an implicit
104  // cast that yields the unbridged-cast placeholder type.
105  if (IsARCUnbridgedCast) {
106  castExpr = ImplicitCastExpr::Create(Self.Context,
108  CK_Dependent, castExpr, nullptr,
109  castExpr->getValueKind());
110  }
111  updatePartOfExplicitCastFlags(castExpr);
112  return castExpr;
113  }
114 
115  // Internal convenience methods.
116 
117  /// Try to handle the given placeholder expression kind. Return
118  /// true if the source expression has the appropriate placeholder
119  /// kind. A placeholder can only be claimed once.
120  bool claimPlaceholder(BuiltinType::Kind K) {
121  if (PlaceholderKind != K) return false;
122 
123  PlaceholderKind = (BuiltinType::Kind) 0;
124  return true;
125  }
126 
127  bool isPlaceholder() const {
128  return PlaceholderKind != 0;
129  }
130  bool isPlaceholder(BuiltinType::Kind K) const {
131  return PlaceholderKind == K;
132  }
133 
134  void checkCastAlign() {
135  Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange);
136  }
137 
138  void checkObjCConversion(Sema::CheckedConversionKind CCK) {
140 
141  Expr *src = SrcExpr.get();
142  if (Self.CheckObjCConversion(OpRange, DestType, src, CCK) ==
144  IsARCUnbridgedCast = true;
145  SrcExpr = src;
146  }
147 
148  /// Check for and handle non-overload placeholder expressions.
149  void checkNonOverloadPlaceholders() {
150  if (!isPlaceholder() || isPlaceholder(BuiltinType::Overload))
151  return;
152 
153  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
154  if (SrcExpr.isInvalid())
155  return;
156  PlaceholderKind = (BuiltinType::Kind) 0;
157  }
158  };
159 }
160 
161 static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
162  QualType DestType);
163 
164 // The Try functions attempt a specific way of casting. If they succeed, they
165 // return TC_Success. If their way of casting is not appropriate for the given
166 // arguments, they return TC_NotApplicable and *may* set diag to a diagnostic
167 // to emit if no other way succeeds. If their way of casting is appropriate but
168 // fails, they return TC_Failed and *must* set diag; they can set it to 0 if
169 // they emit a specialized diagnostic.
170 // All diagnostics returned by these functions must expect the same three
171 // arguments:
172 // %0: Cast Type (a value from the CastType enumeration)
173 // %1: Source Type
174 // %2: Destination Type
175 static TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
176  QualType DestType, bool CStyle,
177  CastKind &Kind,
178  CXXCastPath &BasePath,
179  unsigned &msg);
180 static TryCastResult TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr,
181  QualType DestType, bool CStyle,
182  SourceRange OpRange,
183  unsigned &msg,
184  CastKind &Kind,
185  CXXCastPath &BasePath);
187  QualType DestType, bool CStyle,
188  SourceRange OpRange,
189  unsigned &msg,
190  CastKind &Kind,
191  CXXCastPath &BasePath);
192 static TryCastResult TryStaticDowncast(Sema &Self, CanQualType SrcType,
193  CanQualType DestType, bool CStyle,
194  SourceRange OpRange,
195  QualType OrigSrcType,
196  QualType OrigDestType, unsigned &msg,
197  CastKind &Kind,
198  CXXCastPath &BasePath);
200  QualType SrcType,
201  QualType DestType,bool CStyle,
202  SourceRange OpRange,
203  unsigned &msg,
204  CastKind &Kind,
205  CXXCastPath &BasePath);
206 
207 static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr,
208  QualType DestType,
210  SourceRange OpRange,
211  unsigned &msg, CastKind &Kind,
212  bool ListInitialization);
213 static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
214  QualType DestType,
216  SourceRange OpRange,
217  unsigned &msg, CastKind &Kind,
218  CXXCastPath &BasePath,
219  bool ListInitialization);
220 static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
221  QualType DestType, bool CStyle,
222  unsigned &msg);
223 static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
224  QualType DestType, bool CStyle,
225  SourceRange OpRange,
226  unsigned &msg,
227  CastKind &Kind);
228 
229 
230 /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
233  SourceLocation LAngleBracketLoc, Declarator &D,
234  SourceLocation RAngleBracketLoc,
235  SourceLocation LParenLoc, Expr *E,
236  SourceLocation RParenLoc) {
237 
238  assert(!D.isInvalidType());
239 
240  TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, E->getType());
241  if (D.isInvalidType())
242  return ExprError();
243 
244  if (getLangOpts().CPlusPlus) {
245  // Check that there are no default arguments (C++ only).
246  CheckExtraCXXDefaultArguments(D);
247  }
248 
249  return BuildCXXNamedCast(OpLoc, Kind, TInfo, E,
250  SourceRange(LAngleBracketLoc, RAngleBracketLoc),
251  SourceRange(LParenLoc, RParenLoc));
252 }
253 
256  TypeSourceInfo *DestTInfo, Expr *E,
257  SourceRange AngleBrackets, SourceRange Parens) {
258  ExprResult Ex = E;
259  QualType DestType = DestTInfo->getType();
260 
261  // If the type is dependent, we won't do the semantic analysis now.
262  bool TypeDependent =
263  DestType->isDependentType() || Ex.get()->isTypeDependent();
264 
265  CastOperation Op(*this, DestType, E);
266  Op.OpRange = SourceRange(OpLoc, Parens.getEnd());
267  Op.DestRange = AngleBrackets;
268 
269  switch (Kind) {
270  default: llvm_unreachable("Unknown C++ cast!");
271 
272  case tok::kw_const_cast:
273  if (!TypeDependent) {
274  Op.CheckConstCast();
275  if (Op.SrcExpr.isInvalid())
276  return ExprError();
277  DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
278  }
279  return Op.complete(CXXConstCastExpr::Create(Context, Op.ResultType,
280  Op.ValueKind, Op.SrcExpr.get(), DestTInfo,
281  OpLoc, Parens.getEnd(),
282  AngleBrackets));
283 
284  case tok::kw_dynamic_cast: {
285  // OpenCL C++ 1.0 s2.9: dynamic_cast is not supported.
286  if (getLangOpts().OpenCLCPlusPlus) {
287  return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
288  << "dynamic_cast");
289  }
290 
291  if (!TypeDependent) {
292  Op.CheckDynamicCast();
293  if (Op.SrcExpr.isInvalid())
294  return ExprError();
295  }
296  return Op.complete(CXXDynamicCastExpr::Create(Context, Op.ResultType,
297  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
298  &Op.BasePath, DestTInfo,
299  OpLoc, Parens.getEnd(),
300  AngleBrackets));
301  }
302  case tok::kw_reinterpret_cast: {
303  if (!TypeDependent) {
304  Op.CheckReinterpretCast();
305  if (Op.SrcExpr.isInvalid())
306  return ExprError();
307  DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
308  }
309  return Op.complete(CXXReinterpretCastExpr::Create(Context, Op.ResultType,
310  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
311  nullptr, DestTInfo, OpLoc,
312  Parens.getEnd(),
313  AngleBrackets));
314  }
315  case tok::kw_static_cast: {
316  if (!TypeDependent) {
317  Op.CheckStaticCast();
318  if (Op.SrcExpr.isInvalid())
319  return ExprError();
320  DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
321  }
322 
323  return Op.complete(CXXStaticCastExpr::Create(Context, Op.ResultType,
324  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
325  &Op.BasePath, DestTInfo,
326  OpLoc, Parens.getEnd(),
327  AngleBrackets));
328  }
329  }
330 }
331 
332 /// Try to diagnose a failed overloaded cast. Returns true if
333 /// diagnostics were emitted.
335  SourceRange range, Expr *src,
336  QualType destType,
337  bool listInitialization) {
338  switch (CT) {
339  // These cast kinds don't consider user-defined conversions.
340  case CT_Const:
341  case CT_Reinterpret:
342  case CT_Dynamic:
343  return false;
344 
345  // These do.
346  case CT_Static:
347  case CT_CStyle:
348  case CT_Functional:
349  break;
350  }
351 
352  QualType srcType = src->getType();
353  if (!destType->isRecordType() && !srcType->isRecordType())
354  return false;
355 
357  InitializationKind initKind
359  range, listInitialization)
361  listInitialization)
362  : InitializationKind::CreateCast(/*type range?*/ range);
363  InitializationSequence sequence(S, entity, initKind, src);
364 
365  assert(sequence.Failed() && "initialization succeeded on second try?");
366  switch (sequence.getFailureKind()) {
367  default: return false;
368 
371  break;
372  }
373 
374  OverloadCandidateSet &candidates = sequence.getFailedCandidateSet();
375 
376  unsigned msg = 0;
378 
379  switch (sequence.getFailedOverloadResult()) {
380  case OR_Success: llvm_unreachable("successful failed overload");
382  if (candidates.empty())
383  msg = diag::err_ovl_no_conversion_in_cast;
384  else
385  msg = diag::err_ovl_no_viable_conversion_in_cast;
386  howManyCandidates = OCD_AllCandidates;
387  break;
388 
389  case OR_Ambiguous:
390  msg = diag::err_ovl_ambiguous_conversion_in_cast;
391  howManyCandidates = OCD_ViableCandidates;
392  break;
393 
394  case OR_Deleted:
395  msg = diag::err_ovl_deleted_conversion_in_cast;
396  howManyCandidates = OCD_ViableCandidates;
397  break;
398  }
399 
400  S.Diag(range.getBegin(), msg)
401  << CT << srcType << destType
402  << range << src->getSourceRange();
403 
404  candidates.NoteCandidates(S, howManyCandidates, src);
405 
406  return true;
407 }
408 
409 /// Diagnose a failed cast.
410 static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType,
411  SourceRange opRange, Expr *src, QualType destType,
412  bool listInitialization) {
413  if (msg == diag::err_bad_cxx_cast_generic &&
414  tryDiagnoseOverloadedCast(S, castType, opRange, src, destType,
415  listInitialization))
416  return;
417 
418  S.Diag(opRange.getBegin(), msg) << castType
419  << src->getType() << destType << opRange << src->getSourceRange();
420 
421  // Detect if both types are (ptr to) class, and note any incompleteness.
422  int DifferentPtrness = 0;
423  QualType From = destType;
424  if (auto Ptr = From->getAs<PointerType>()) {
425  From = Ptr->getPointeeType();
426  DifferentPtrness++;
427  }
428  QualType To = src->getType();
429  if (auto Ptr = To->getAs<PointerType>()) {
430  To = Ptr->getPointeeType();
431  DifferentPtrness--;
432  }
433  if (!DifferentPtrness) {
434  auto RecFrom = From->getAs<RecordType>();
435  auto RecTo = To->getAs<RecordType>();
436  if (RecFrom && RecTo) {
437  auto DeclFrom = RecFrom->getAsCXXRecordDecl();
438  if (!DeclFrom->isCompleteDefinition())
439  S.Diag(DeclFrom->getLocation(), diag::note_type_incomplete)
440  << DeclFrom->getDeclName();
441  auto DeclTo = RecTo->getAsCXXRecordDecl();
442  if (!DeclTo->isCompleteDefinition())
443  S.Diag(DeclTo->getLocation(), diag::note_type_incomplete)
444  << DeclTo->getDeclName();
445  }
446  }
447 }
448 
449 namespace {
450 /// The kind of unwrapping we did when determining whether a conversion casts
451 /// away constness.
453  /// The conversion does not cast away constness.
454  CACK_None = 0,
455  /// We unwrapped similar types.
456  CACK_Similar = 1,
457  /// We unwrapped dissimilar types with similar representations (eg, a pointer
458  /// versus an Objective-C object pointer).
459  CACK_SimilarKind = 2,
460  /// We unwrapped representationally-unrelated types, such as a pointer versus
461  /// a pointer-to-member.
462  CACK_Incoherent = 3,
463 };
464 }
465 
466 /// Unwrap one level of types for CastsAwayConstness.
467 ///
468 /// Like Sema::UnwrapSimilarTypes, this removes one level of indirection from
469 /// both types, provided that they're both pointer-like or array-like. Unlike
470 /// the Sema function, doesn't care if the unwrapped pieces are related.
471 ///
472 /// This function may remove additional levels as necessary for correctness:
473 /// the resulting T1 is unwrapped sufficiently that it is never an array type,
474 /// so that its qualifiers can be directly compared to those of T2 (which will
475 /// have the combined set of qualifiers from all indermediate levels of T2),
476 /// as (effectively) required by [expr.const.cast]p7 replacing T1's qualifiers
477 /// with those from T2.
480  enum { None, Ptr, MemPtr, BlockPtr, Array };
481  auto Classify = [](QualType T) {
482  if (T->isAnyPointerType()) return Ptr;
483  if (T->isMemberPointerType()) return MemPtr;
484  if (T->isBlockPointerType()) return BlockPtr;
485  // We somewhat-arbitrarily don't look through VLA types here. This is at
486  // least consistent with the behavior of UnwrapSimilarTypes.
487  if (T->isConstantArrayType() || T->isIncompleteArrayType()) return Array;
488  return None;
489  };
490 
491  auto Unwrap = [&](QualType T) {
492  if (auto *AT = Context.getAsArrayType(T))
493  return AT->getElementType();
494  return T->getPointeeType();
495  };
496 
498 
499  if (T2->isReferenceType()) {
500  // Special case: if the destination type is a reference type, unwrap it as
501  // the first level. (The source will have been an lvalue expression in this
502  // case, so there is no corresponding "reference to" in T1 to remove.) This
503  // simulates removing a "pointer to" from both sides.
504  T2 = T2->getPointeeType();
505  Kind = CastAwayConstnessKind::CACK_Similar;
506  } else if (Context.UnwrapSimilarTypes(T1, T2)) {
507  Kind = CastAwayConstnessKind::CACK_Similar;
508  } else {
509  // Try unwrapping mismatching levels.
510  int T1Class = Classify(T1);
511  if (T1Class == None)
512  return CastAwayConstnessKind::CACK_None;
513 
514  int T2Class = Classify(T2);
515  if (T2Class == None)
516  return CastAwayConstnessKind::CACK_None;
517 
518  T1 = Unwrap(T1);
519  T2 = Unwrap(T2);
520  Kind = T1Class == T2Class ? CastAwayConstnessKind::CACK_SimilarKind
521  : CastAwayConstnessKind::CACK_Incoherent;
522  }
523 
524  // We've unwrapped at least one level. If the resulting T1 is a (possibly
525  // multidimensional) array type, any qualifier on any matching layer of
526  // T2 is considered to correspond to T1. Decompose down to the element
527  // type of T1 so that we can compare properly.
528  while (true) {
529  Context.UnwrapSimilarArrayTypes(T1, T2);
530 
531  if (Classify(T1) != Array)
532  break;
533 
534  auto T2Class = Classify(T2);
535  if (T2Class == None)
536  break;
537 
538  if (T2Class != Array)
539  Kind = CastAwayConstnessKind::CACK_Incoherent;
540  else if (Kind != CastAwayConstnessKind::CACK_Incoherent)
541  Kind = CastAwayConstnessKind::CACK_SimilarKind;
542 
543  T1 = Unwrap(T1);
544  T2 = Unwrap(T2).withCVRQualifiers(T2.getCVRQualifiers());
545  }
546 
547  return Kind;
548 }
549 
550 /// Check if the pointer conversion from SrcType to DestType casts away
551 /// constness as defined in C++ [expr.const.cast]. This is used by the cast
552 /// checkers. Both arguments must denote pointer (possibly to member) types.
553 ///
554 /// \param CheckCVR Whether to check for const/volatile/restrict qualifiers.
555 /// \param CheckObjCLifetime Whether to check Objective-C lifetime qualifiers.
557 CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType,
558  bool CheckCVR, bool CheckObjCLifetime,
559  QualType *TheOffendingSrcType = nullptr,
560  QualType *TheOffendingDestType = nullptr,
561  Qualifiers *CastAwayQualifiers = nullptr) {
562  // If the only checking we care about is for Objective-C lifetime qualifiers,
563  // and we're not in ObjC mode, there's nothing to check.
564  if (!CheckCVR && CheckObjCLifetime && !Self.Context.getLangOpts().ObjC1)
565  return CastAwayConstnessKind::CACK_None;
566 
567  if (!DestType->isReferenceType()) {
568  assert((SrcType->isAnyPointerType() || SrcType->isMemberPointerType() ||
569  SrcType->isBlockPointerType()) &&
570  "Source type is not pointer or pointer to member.");
571  assert((DestType->isAnyPointerType() || DestType->isMemberPointerType() ||
572  DestType->isBlockPointerType()) &&
573  "Destination type is not pointer or pointer to member.");
574  }
575 
576  QualType UnwrappedSrcType = Self.Context.getCanonicalType(SrcType),
577  UnwrappedDestType = Self.Context.getCanonicalType(DestType);
578 
579  // Find the qualifiers. We only care about cvr-qualifiers for the
580  // purpose of this check, because other qualifiers (address spaces,
581  // Objective-C GC, etc.) are part of the type's identity.
582  QualType PrevUnwrappedSrcType = UnwrappedSrcType;
583  QualType PrevUnwrappedDestType = UnwrappedDestType;
584  auto WorstKind = CastAwayConstnessKind::CACK_Similar;
585  bool AllConstSoFar = true;
586  while (auto Kind = unwrapCastAwayConstnessLevel(
587  Self.Context, UnwrappedSrcType, UnwrappedDestType)) {
588  // Track the worst kind of unwrap we needed to do before we found a
589  // problem.
590  if (Kind > WorstKind)
591  WorstKind = Kind;
592 
593  // Determine the relevant qualifiers at this level.
594  Qualifiers SrcQuals, DestQuals;
595  Self.Context.getUnqualifiedArrayType(UnwrappedSrcType, SrcQuals);
596  Self.Context.getUnqualifiedArrayType(UnwrappedDestType, DestQuals);
597 
598  // We do not meaningfully track object const-ness of Objective-C object
599  // types. Remove const from the source type if either the source or
600  // the destination is an Objective-C object type.
601  if (UnwrappedSrcType->isObjCObjectType() ||
602  UnwrappedDestType->isObjCObjectType())
603  SrcQuals.removeConst();
604 
605  if (CheckCVR) {
606  Qualifiers SrcCvrQuals =
608  Qualifiers DestCvrQuals =
610 
611  if (SrcCvrQuals != DestCvrQuals) {
612  if (CastAwayQualifiers)
613  *CastAwayQualifiers = SrcCvrQuals - DestCvrQuals;
614 
615  // If we removed a cvr-qualifier, this is casting away 'constness'.
616  if (!DestCvrQuals.compatiblyIncludes(SrcCvrQuals)) {
617  if (TheOffendingSrcType)
618  *TheOffendingSrcType = PrevUnwrappedSrcType;
619  if (TheOffendingDestType)
620  *TheOffendingDestType = PrevUnwrappedDestType;
621  return WorstKind;
622  }
623 
624  // If any prior level was not 'const', this is also casting away
625  // 'constness'. We noted the outermost type missing a 'const' already.
626  if (!AllConstSoFar)
627  return WorstKind;
628  }
629  }
630 
631  if (CheckObjCLifetime &&
632  !DestQuals.compatiblyIncludesObjCLifetime(SrcQuals))
633  return WorstKind;
634 
635  // If we found our first non-const-qualified type, this may be the place
636  // where things start to go wrong.
637  if (AllConstSoFar && !DestQuals.hasConst()) {
638  AllConstSoFar = false;
639  if (TheOffendingSrcType)
640  *TheOffendingSrcType = PrevUnwrappedSrcType;
641  if (TheOffendingDestType)
642  *TheOffendingDestType = PrevUnwrappedDestType;
643  }
644 
645  PrevUnwrappedSrcType = UnwrappedSrcType;
646  PrevUnwrappedDestType = UnwrappedDestType;
647  }
648 
649  return CastAwayConstnessKind::CACK_None;
650 }
651 
653  unsigned &DiagID) {
654  switch (CACK) {
655  case CastAwayConstnessKind::CACK_None:
656  llvm_unreachable("did not cast away constness");
657 
658  case CastAwayConstnessKind::CACK_Similar:
659  // FIXME: Accept these as an extension too?
660  case CastAwayConstnessKind::CACK_SimilarKind:
661  DiagID = diag::err_bad_cxx_cast_qualifiers_away;
662  return TC_Failed;
663 
664  case CastAwayConstnessKind::CACK_Incoherent:
665  DiagID = diag::ext_bad_cxx_cast_qualifiers_away_incoherent;
666  return TC_Extension;
667  }
668 
669  llvm_unreachable("unexpected cast away constness kind");
670 }
671 
672 /// CheckDynamicCast - Check that a dynamic_cast<DestType>(SrcExpr) is valid.
673 /// Refer to C++ 5.2.7 for details. Dynamic casts are used mostly for runtime-
674 /// checked downcasts in class hierarchies.
675 void CastOperation::CheckDynamicCast() {
676  if (ValueKind == VK_RValue)
677  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
678  else if (isPlaceholder())
679  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
680  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
681  return;
682 
683  QualType OrigSrcType = SrcExpr.get()->getType();
684  QualType DestType = Self.Context.getCanonicalType(this->DestType);
685 
686  // C++ 5.2.7p1: T shall be a pointer or reference to a complete class type,
687  // or "pointer to cv void".
688 
689  QualType DestPointee;
690  const PointerType *DestPointer = DestType->getAs<PointerType>();
691  const ReferenceType *DestReference = nullptr;
692  if (DestPointer) {
693  DestPointee = DestPointer->getPointeeType();
694  } else if ((DestReference = DestType->getAs<ReferenceType>())) {
695  DestPointee = DestReference->getPointeeType();
696  } else {
697  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ref_or_ptr)
698  << this->DestType << DestRange;
699  SrcExpr = ExprError();
700  return;
701  }
702 
703  const RecordType *DestRecord = DestPointee->getAs<RecordType>();
704  if (DestPointee->isVoidType()) {
705  assert(DestPointer && "Reference to void is not possible");
706  } else if (DestRecord) {
707  if (Self.RequireCompleteType(OpRange.getBegin(), DestPointee,
708  diag::err_bad_dynamic_cast_incomplete,
709  DestRange)) {
710  SrcExpr = ExprError();
711  return;
712  }
713  } else {
714  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
715  << DestPointee.getUnqualifiedType() << DestRange;
716  SrcExpr = ExprError();
717  return;
718  }
719 
720  // C++0x 5.2.7p2: If T is a pointer type, v shall be an rvalue of a pointer to
721  // complete class type, [...]. If T is an lvalue reference type, v shall be
722  // an lvalue of a complete class type, [...]. If T is an rvalue reference
723  // type, v shall be an expression having a complete class type, [...]
724  QualType SrcType = Self.Context.getCanonicalType(OrigSrcType);
725  QualType SrcPointee;
726  if (DestPointer) {
727  if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
728  SrcPointee = SrcPointer->getPointeeType();
729  } else {
730  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ptr)
731  << OrigSrcType << SrcExpr.get()->getSourceRange();
732  SrcExpr = ExprError();
733  return;
734  }
735  } else if (DestReference->isLValueReferenceType()) {
736  if (!SrcExpr.get()->isLValue()) {
737  Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
738  << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
739  }
740  SrcPointee = SrcType;
741  } else {
742  // If we're dynamic_casting from a prvalue to an rvalue reference, we need
743  // to materialize the prvalue before we bind the reference to it.
744  if (SrcExpr.get()->isRValue())
745  SrcExpr = Self.CreateMaterializeTemporaryExpr(
746  SrcType, SrcExpr.get(), /*IsLValueReference*/ false);
747  SrcPointee = SrcType;
748  }
749 
750  const RecordType *SrcRecord = SrcPointee->getAs<RecordType>();
751  if (SrcRecord) {
752  if (Self.RequireCompleteType(OpRange.getBegin(), SrcPointee,
753  diag::err_bad_dynamic_cast_incomplete,
754  SrcExpr.get())) {
755  SrcExpr = ExprError();
756  return;
757  }
758  } else {
759  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
760  << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
761  SrcExpr = ExprError();
762  return;
763  }
764 
765  assert((DestPointer || DestReference) &&
766  "Bad destination non-ptr/ref slipped through.");
767  assert((DestRecord || DestPointee->isVoidType()) &&
768  "Bad destination pointee slipped through.");
769  assert(SrcRecord && "Bad source pointee slipped through.");
770 
771  // C++ 5.2.7p1: The dynamic_cast operator shall not cast away constness.
772  if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
773  Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_qualifiers_away)
774  << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
775  SrcExpr = ExprError();
776  return;
777  }
778 
779  // C++ 5.2.7p3: If the type of v is the same as the required result type,
780  // [except for cv].
781  if (DestRecord == SrcRecord) {
782  Kind = CK_NoOp;
783  return;
784  }
785 
786  // C++ 5.2.7p5
787  // Upcasts are resolved statically.
788  if (DestRecord &&
789  Self.IsDerivedFrom(OpRange.getBegin(), SrcPointee, DestPointee)) {
790  if (Self.CheckDerivedToBaseConversion(SrcPointee, DestPointee,
791  OpRange.getBegin(), OpRange,
792  &BasePath)) {
793  SrcExpr = ExprError();
794  return;
795  }
796 
797  Kind = CK_DerivedToBase;
798  return;
799  }
800 
801  // C++ 5.2.7p6: Otherwise, v shall be [polymorphic].
802  const RecordDecl *SrcDecl = SrcRecord->getDecl()->getDefinition();
803  assert(SrcDecl && "Definition missing");
804  if (!cast<CXXRecordDecl>(SrcDecl)->isPolymorphic()) {
805  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_polymorphic)
806  << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
807  SrcExpr = ExprError();
808  }
809 
810  // dynamic_cast is not available with -fno-rtti.
811  // As an exception, dynamic_cast to void* is available because it doesn't
812  // use RTTI.
813  if (!Self.getLangOpts().RTTI && !DestPointee->isVoidType()) {
814  Self.Diag(OpRange.getBegin(), diag::err_no_dynamic_cast_with_fno_rtti);
815  SrcExpr = ExprError();
816  return;
817  }
818 
819  // Done. Everything else is run-time checks.
820  Kind = CK_Dynamic;
821 }
822 
823 /// CheckConstCast - Check that a const_cast<DestType>(SrcExpr) is valid.
824 /// Refer to C++ 5.2.11 for details. const_cast is typically used in code
825 /// like this:
826 /// const char *str = "literal";
827 /// legacy_function(const_cast<char*>(str));
828 void CastOperation::CheckConstCast() {
829  if (ValueKind == VK_RValue)
830  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
831  else if (isPlaceholder())
832  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
833  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
834  return;
835 
836  unsigned msg = diag::err_bad_cxx_cast_generic;
837  auto TCR = TryConstCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg);
838  if (TCR != TC_Success && msg != 0) {
839  Self.Diag(OpRange.getBegin(), msg) << CT_Const
840  << SrcExpr.get()->getType() << DestType << OpRange;
841  }
842  if (!isValidCast(TCR))
843  SrcExpr = ExprError();
844 }
845 
846 /// Check that a reinterpret_cast<DestType>(SrcExpr) is not used as upcast
847 /// or downcast between respective pointers or references.
848 static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
849  QualType DestType,
850  SourceRange OpRange) {
851  QualType SrcType = SrcExpr->getType();
852  // When casting from pointer or reference, get pointee type; use original
853  // type otherwise.
854  const CXXRecordDecl *SrcPointeeRD = SrcType->getPointeeCXXRecordDecl();
855  const CXXRecordDecl *SrcRD =
856  SrcPointeeRD ? SrcPointeeRD : SrcType->getAsCXXRecordDecl();
857 
858  // Examining subobjects for records is only possible if the complete and
859  // valid definition is available. Also, template instantiation is not
860  // allowed here.
861  if (!SrcRD || !SrcRD->isCompleteDefinition() || SrcRD->isInvalidDecl())
862  return;
863 
864  const CXXRecordDecl *DestRD = DestType->getPointeeCXXRecordDecl();
865 
866  if (!DestRD || !DestRD->isCompleteDefinition() || DestRD->isInvalidDecl())
867  return;
868 
869  enum {
870  ReinterpretUpcast,
871  ReinterpretDowncast
872  } ReinterpretKind;
873 
874  CXXBasePaths BasePaths;
875 
876  if (SrcRD->isDerivedFrom(DestRD, BasePaths))
877  ReinterpretKind = ReinterpretUpcast;
878  else if (DestRD->isDerivedFrom(SrcRD, BasePaths))
879  ReinterpretKind = ReinterpretDowncast;
880  else
881  return;
882 
883  bool VirtualBase = true;
884  bool NonZeroOffset = false;
885  for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(),
886  E = BasePaths.end();
887  I != E; ++I) {
888  const CXXBasePath &Path = *I;
890  bool IsVirtual = false;
891  for (CXXBasePath::const_iterator IElem = Path.begin(), EElem = Path.end();
892  IElem != EElem; ++IElem) {
893  IsVirtual = IElem->Base->isVirtual();
894  if (IsVirtual)
895  break;
896  const CXXRecordDecl *BaseRD = IElem->Base->getType()->getAsCXXRecordDecl();
897  assert(BaseRD && "Base type should be a valid unqualified class type");
898  // Don't check if any base has invalid declaration or has no definition
899  // since it has no layout info.
900  const CXXRecordDecl *Class = IElem->Class,
901  *ClassDefinition = Class->getDefinition();
902  if (Class->isInvalidDecl() || !ClassDefinition ||
903  !ClassDefinition->isCompleteDefinition())
904  return;
905 
906  const ASTRecordLayout &DerivedLayout =
907  Self.Context.getASTRecordLayout(Class);
908  Offset += DerivedLayout.getBaseClassOffset(BaseRD);
909  }
910  if (!IsVirtual) {
911  // Don't warn if any path is a non-virtually derived base at offset zero.
912  if (Offset.isZero())
913  return;
914  // Offset makes sense only for non-virtual bases.
915  else
916  NonZeroOffset = true;
917  }
918  VirtualBase = VirtualBase && IsVirtual;
919  }
920 
921  (void) NonZeroOffset; // Silence set but not used warning.
922  assert((VirtualBase || NonZeroOffset) &&
923  "Should have returned if has non-virtual base with zero offset");
924 
925  QualType BaseType =
926  ReinterpretKind == ReinterpretUpcast? DestType : SrcType;
927  QualType DerivedType =
928  ReinterpretKind == ReinterpretUpcast? SrcType : DestType;
929 
930  SourceLocation BeginLoc = OpRange.getBegin();
931  Self.Diag(BeginLoc, diag::warn_reinterpret_different_from_static)
932  << DerivedType << BaseType << !VirtualBase << int(ReinterpretKind)
933  << OpRange;
934  Self.Diag(BeginLoc, diag::note_reinterpret_updowncast_use_static)
935  << int(ReinterpretKind)
936  << FixItHint::CreateReplacement(BeginLoc, "static_cast");
937 }
938 
939 /// CheckReinterpretCast - Check that a reinterpret_cast<DestType>(SrcExpr) is
940 /// valid.
941 /// Refer to C++ 5.2.10 for details. reinterpret_cast is typically used in code
942 /// like this:
943 /// char *bytes = reinterpret_cast<char*>(int_ptr);
944 void CastOperation::CheckReinterpretCast() {
945  if (ValueKind == VK_RValue && !isPlaceholder(BuiltinType::Overload))
946  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
947  else
948  checkNonOverloadPlaceholders();
949  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
950  return;
951 
952  unsigned msg = diag::err_bad_cxx_cast_generic;
953  TryCastResult tcr =
954  TryReinterpretCast(Self, SrcExpr, DestType,
955  /*CStyle*/false, OpRange, msg, Kind);
956  if (tcr != TC_Success && msg != 0) {
957  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
958  return;
959  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
960  //FIXME: &f<int>; is overloaded and resolvable
961  Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_overload)
962  << OverloadExpr::find(SrcExpr.get()).Expression->getName()
963  << DestType << OpRange;
964  Self.NoteAllOverloadCandidates(SrcExpr.get());
965 
966  } else {
967  diagnoseBadCast(Self, msg, CT_Reinterpret, OpRange, SrcExpr.get(),
968  DestType, /*listInitialization=*/false);
969  }
970  }
971 
972  if (isValidCast(tcr)) {
974  checkObjCConversion(Sema::CCK_OtherCast);
975  DiagnoseReinterpretUpDownCast(Self, SrcExpr.get(), DestType, OpRange);
976  } else {
977  SrcExpr = ExprError();
978  }
979 }
980 
981 
982 /// CheckStaticCast - Check that a static_cast<DestType>(SrcExpr) is valid.
983 /// Refer to C++ 5.2.9 for details. Static casts are mostly used for making
984 /// implicit conversions explicit and getting rid of data loss warnings.
985 void CastOperation::CheckStaticCast() {
986  if (isPlaceholder()) {
987  checkNonOverloadPlaceholders();
988  if (SrcExpr.isInvalid())
989  return;
990  }
991 
992  // This test is outside everything else because it's the only case where
993  // a non-lvalue-reference target type does not lead to decay.
994  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
995  if (DestType->isVoidType()) {
996  Kind = CK_ToVoid;
997 
998  if (claimPlaceholder(BuiltinType::Overload)) {
1000  false, // Decay Function to ptr
1001  true, // Complain
1002  OpRange, DestType, diag::err_bad_static_cast_overload);
1003  if (SrcExpr.isInvalid())
1004  return;
1005  }
1006 
1007  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
1008  return;
1009  }
1010 
1011  if (ValueKind == VK_RValue && !DestType->isRecordType() &&
1012  !isPlaceholder(BuiltinType::Overload)) {
1013  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
1014  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
1015  return;
1016  }
1017 
1018  unsigned msg = diag::err_bad_cxx_cast_generic;
1019  TryCastResult tcr
1020  = TryStaticCast(Self, SrcExpr, DestType, Sema::CCK_OtherCast, OpRange, msg,
1021  Kind, BasePath, /*ListInitialization=*/false);
1022  if (tcr != TC_Success && msg != 0) {
1023  if (SrcExpr.isInvalid())
1024  return;
1025  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1026  OverloadExpr* oe = OverloadExpr::find(SrcExpr.get()).Expression;
1027  Self.Diag(OpRange.getBegin(), diag::err_bad_static_cast_overload)
1028  << oe->getName() << DestType << OpRange
1029  << oe->getQualifierLoc().getSourceRange();
1030  Self.NoteAllOverloadCandidates(SrcExpr.get());
1031  } else {
1032  diagnoseBadCast(Self, msg, CT_Static, OpRange, SrcExpr.get(), DestType,
1033  /*listInitialization=*/false);
1034  }
1035  }
1036 
1037  if (isValidCast(tcr)) {
1038  if (Kind == CK_BitCast)
1039  checkCastAlign();
1041  checkObjCConversion(Sema::CCK_OtherCast);
1042  } else {
1043  SrcExpr = ExprError();
1044  }
1045 }
1046 
1047 /// TryStaticCast - Check if a static cast can be performed, and do so if
1048 /// possible. If @p CStyle, ignore access restrictions on hierarchy casting
1049 /// and casting away constness.
1051  QualType DestType,
1053  SourceRange OpRange, unsigned &msg,
1054  CastKind &Kind, CXXCastPath &BasePath,
1055  bool ListInitialization) {
1056  // Determine whether we have the semantics of a C-style cast.
1057  bool CStyle
1058  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1059 
1060  // The order the tests is not entirely arbitrary. There is one conversion
1061  // that can be handled in two different ways. Given:
1062  // struct A {};
1063  // struct B : public A {
1064  // B(); B(const A&);
1065  // };
1066  // const A &a = B();
1067  // the cast static_cast<const B&>(a) could be seen as either a static
1068  // reference downcast, or an explicit invocation of the user-defined
1069  // conversion using B's conversion constructor.
1070  // DR 427 specifies that the downcast is to be applied here.
1071 
1072  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
1073  // Done outside this function.
1074 
1075  TryCastResult tcr;
1076 
1077  // C++ 5.2.9p5, reference downcast.
1078  // See the function for details.
1079  // DR 427 specifies that this is to be applied before paragraph 2.
1080  tcr = TryStaticReferenceDowncast(Self, SrcExpr.get(), DestType, CStyle,
1081  OpRange, msg, Kind, BasePath);
1082  if (tcr != TC_NotApplicable)
1083  return tcr;
1084 
1085  // C++11 [expr.static.cast]p3:
1086  // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to cv2
1087  // T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1088  tcr = TryLValueToRValueCast(Self, SrcExpr.get(), DestType, CStyle, Kind,
1089  BasePath, msg);
1090  if (tcr != TC_NotApplicable)
1091  return tcr;
1092 
1093  // C++ 5.2.9p2: An expression e can be explicitly converted to a type T
1094  // [...] if the declaration "T t(e);" is well-formed, [...].
1095  tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg,
1096  Kind, ListInitialization);
1097  if (SrcExpr.isInvalid())
1098  return TC_Failed;
1099  if (tcr != TC_NotApplicable)
1100  return tcr;
1101 
1102  // C++ 5.2.9p6: May apply the reverse of any standard conversion, except
1103  // lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
1104  // conversions, subject to further restrictions.
1105  // Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
1106  // of qualification conversions impossible.
1107  // In the CStyle case, the earlier attempt to const_cast should have taken
1108  // care of reverse qualification conversions.
1109 
1110  QualType SrcType = Self.Context.getCanonicalType(SrcExpr.get()->getType());
1111 
1112  // C++0x 5.2.9p9: A value of a scoped enumeration type can be explicitly
1113  // converted to an integral type. [...] A value of a scoped enumeration type
1114  // can also be explicitly converted to a floating-point type [...].
1115  if (const EnumType *Enum = SrcType->getAs<EnumType>()) {
1116  if (Enum->getDecl()->isScoped()) {
1117  if (DestType->isBooleanType()) {
1118  Kind = CK_IntegralToBoolean;
1119  return TC_Success;
1120  } else if (DestType->isIntegralType(Self.Context)) {
1121  Kind = CK_IntegralCast;
1122  return TC_Success;
1123  } else if (DestType->isRealFloatingType()) {
1124  Kind = CK_IntegralToFloating;
1125  return TC_Success;
1126  }
1127  }
1128  }
1129 
1130  // Reverse integral promotion/conversion. All such conversions are themselves
1131  // again integral promotions or conversions and are thus already handled by
1132  // p2 (TryDirectInitialization above).
1133  // (Note: any data loss warnings should be suppressed.)
1134  // The exception is the reverse of enum->integer, i.e. integer->enum (and
1135  // enum->enum). See also C++ 5.2.9p7.
1136  // The same goes for reverse floating point promotion/conversion and
1137  // floating-integral conversions. Again, only floating->enum is relevant.
1138  if (DestType->isEnumeralType()) {
1139  if (SrcType->isIntegralOrEnumerationType()) {
1140  Kind = CK_IntegralCast;
1141  return TC_Success;
1142  } else if (SrcType->isRealFloatingType()) {
1143  Kind = CK_FloatingToIntegral;
1144  return TC_Success;
1145  }
1146  }
1147 
1148  // Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
1149  // C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
1150  tcr = TryStaticPointerDowncast(Self, SrcType, DestType, CStyle, OpRange, msg,
1151  Kind, BasePath);
1152  if (tcr != TC_NotApplicable)
1153  return tcr;
1154 
1155  // Reverse member pointer conversion. C++ 4.11 specifies member pointer
1156  // conversion. C++ 5.2.9p9 has additional information.
1157  // DR54's access restrictions apply here also.
1158  tcr = TryStaticMemberPointerUpcast(Self, SrcExpr, SrcType, DestType, CStyle,
1159  OpRange, msg, Kind, BasePath);
1160  if (tcr != TC_NotApplicable)
1161  return tcr;
1162 
1163  // Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
1164  // void*. C++ 5.2.9p10 specifies additional restrictions, which really is
1165  // just the usual constness stuff.
1166  if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
1167  QualType SrcPointee = SrcPointer->getPointeeType();
1168  if (SrcPointee->isVoidType()) {
1169  if (const PointerType *DestPointer = DestType->getAs<PointerType>()) {
1170  QualType DestPointee = DestPointer->getPointeeType();
1171  if (DestPointee->isIncompleteOrObjectType()) {
1172  // This is definitely the intended conversion, but it might fail due
1173  // to a qualifier violation. Note that we permit Objective-C lifetime
1174  // and GC qualifier mismatches here.
1175  if (!CStyle) {
1176  Qualifiers DestPointeeQuals = DestPointee.getQualifiers();
1177  Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers();
1178  DestPointeeQuals.removeObjCGCAttr();
1179  DestPointeeQuals.removeObjCLifetime();
1180  SrcPointeeQuals.removeObjCGCAttr();
1181  SrcPointeeQuals.removeObjCLifetime();
1182  if (DestPointeeQuals != SrcPointeeQuals &&
1183  !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) {
1184  msg = diag::err_bad_cxx_cast_qualifiers_away;
1185  return TC_Failed;
1186  }
1187  }
1188  Kind = CK_BitCast;
1189  return TC_Success;
1190  }
1191 
1192  // Microsoft permits static_cast from 'pointer-to-void' to
1193  // 'pointer-to-function'.
1194  if (!CStyle && Self.getLangOpts().MSVCCompat &&
1195  DestPointee->isFunctionType()) {
1196  Self.Diag(OpRange.getBegin(), diag::ext_ms_cast_fn_obj) << OpRange;
1197  Kind = CK_BitCast;
1198  return TC_Success;
1199  }
1200  }
1201  else if (DestType->isObjCObjectPointerType()) {
1202  // allow both c-style cast and static_cast of objective-c pointers as
1203  // they are pervasive.
1204  Kind = CK_CPointerToObjCPointerCast;
1205  return TC_Success;
1206  }
1207  else if (CStyle && DestType->isBlockPointerType()) {
1208  // allow c-style cast of void * to block pointers.
1209  Kind = CK_AnyPointerToBlockPointerCast;
1210  return TC_Success;
1211  }
1212  }
1213  }
1214  // Allow arbitrary objective-c pointer conversion with static casts.
1215  if (SrcType->isObjCObjectPointerType() &&
1216  DestType->isObjCObjectPointerType()) {
1217  Kind = CK_BitCast;
1218  return TC_Success;
1219  }
1220  // Allow ns-pointer to cf-pointer conversion in either direction
1221  // with static casts.
1222  if (!CStyle &&
1223  Self.CheckTollFreeBridgeStaticCast(DestType, SrcExpr.get(), Kind))
1224  return TC_Success;
1225 
1226  // See if it looks like the user is trying to convert between
1227  // related record types, and select a better diagnostic if so.
1228  if (auto SrcPointer = SrcType->getAs<PointerType>())
1229  if (auto DestPointer = DestType->getAs<PointerType>())
1230  if (SrcPointer->getPointeeType()->getAs<RecordType>() &&
1231  DestPointer->getPointeeType()->getAs<RecordType>())
1232  msg = diag::err_bad_cxx_cast_unrelated_class;
1233 
1234  // We tried everything. Everything! Nothing works! :-(
1235  return TC_NotApplicable;
1236 }
1237 
1238 /// Tests whether a conversion according to N2844 is valid.
1240  QualType DestType, bool CStyle,
1241  CastKind &Kind, CXXCastPath &BasePath,
1242  unsigned &msg) {
1243  // C++11 [expr.static.cast]p3:
1244  // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
1245  // cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1246  const RValueReferenceType *R = DestType->getAs<RValueReferenceType>();
1247  if (!R)
1248  return TC_NotApplicable;
1249 
1250  if (!SrcExpr->isGLValue())
1251  return TC_NotApplicable;
1252 
1253  // Because we try the reference downcast before this function, from now on
1254  // this is the only cast possibility, so we issue an error if we fail now.
1255  // FIXME: Should allow casting away constness if CStyle.
1256  bool DerivedToBase;
1257  bool ObjCConversion;
1258  bool ObjCLifetimeConversion;
1259  QualType FromType = SrcExpr->getType();
1260  QualType ToType = R->getPointeeType();
1261  if (CStyle) {
1262  FromType = FromType.getUnqualifiedType();
1263  ToType = ToType.getUnqualifiedType();
1264  }
1265 
1267  SrcExpr->getLocStart(), ToType, FromType, DerivedToBase, ObjCConversion,
1268  ObjCLifetimeConversion);
1269  if (RefResult != Sema::Ref_Compatible) {
1270  if (CStyle || RefResult == Sema::Ref_Incompatible)
1271  return TC_NotApplicable;
1272  // Diagnose types which are reference-related but not compatible here since
1273  // we can provide better diagnostics. In these cases forwarding to
1274  // [expr.static.cast]p4 should never result in a well-formed cast.
1275  msg = SrcExpr->isLValue() ? diag::err_bad_lvalue_to_rvalue_cast
1276  : diag::err_bad_rvalue_to_rvalue_cast;
1277  return TC_Failed;
1278  }
1279 
1280  if (DerivedToBase) {
1281  Kind = CK_DerivedToBase;
1282  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1283  /*DetectVirtual=*/true);
1284  if (!Self.IsDerivedFrom(SrcExpr->getLocStart(), SrcExpr->getType(),
1285  R->getPointeeType(), Paths))
1286  return TC_NotApplicable;
1287 
1288  Self.BuildBasePathArray(Paths, BasePath);
1289  } else
1290  Kind = CK_NoOp;
1291 
1292  return TC_Success;
1293 }
1294 
1295 /// Tests whether a conversion according to C++ 5.2.9p5 is valid.
1297 TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType,
1298  bool CStyle, SourceRange OpRange,
1299  unsigned &msg, CastKind &Kind,
1300  CXXCastPath &BasePath) {
1301  // C++ 5.2.9p5: An lvalue of type "cv1 B", where B is a class type, can be
1302  // cast to type "reference to cv2 D", where D is a class derived from B,
1303  // if a valid standard conversion from "pointer to D" to "pointer to B"
1304  // exists, cv2 >= cv1, and B is not a virtual base class of D.
1305  // In addition, DR54 clarifies that the base must be accessible in the
1306  // current context. Although the wording of DR54 only applies to the pointer
1307  // variant of this rule, the intent is clearly for it to apply to the this
1308  // conversion as well.
1309 
1310  const ReferenceType *DestReference = DestType->getAs<ReferenceType>();
1311  if (!DestReference) {
1312  return TC_NotApplicable;
1313  }
1314  bool RValueRef = DestReference->isRValueReferenceType();
1315  if (!RValueRef && !SrcExpr->isLValue()) {
1316  // We know the left side is an lvalue reference, so we can suggest a reason.
1317  msg = diag::err_bad_cxx_cast_rvalue;
1318  return TC_NotApplicable;
1319  }
1320 
1321  QualType DestPointee = DestReference->getPointeeType();
1322 
1323  // FIXME: If the source is a prvalue, we should issue a warning (because the
1324  // cast always has undefined behavior), and for AST consistency, we should
1325  // materialize a temporary.
1326  return TryStaticDowncast(Self,
1327  Self.Context.getCanonicalType(SrcExpr->getType()),
1328  Self.Context.getCanonicalType(DestPointee), CStyle,
1329  OpRange, SrcExpr->getType(), DestType, msg, Kind,
1330  BasePath);
1331 }
1332 
1333 /// Tests whether a conversion according to C++ 5.2.9p8 is valid.
1336  bool CStyle, SourceRange OpRange,
1337  unsigned &msg, CastKind &Kind,
1338  CXXCastPath &BasePath) {
1339  // C++ 5.2.9p8: An rvalue of type "pointer to cv1 B", where B is a class
1340  // type, can be converted to an rvalue of type "pointer to cv2 D", where D
1341  // is a class derived from B, if a valid standard conversion from "pointer
1342  // to D" to "pointer to B" exists, cv2 >= cv1, and B is not a virtual base
1343  // class of D.
1344  // In addition, DR54 clarifies that the base must be accessible in the
1345  // current context.
1346 
1347  const PointerType *DestPointer = DestType->getAs<PointerType>();
1348  if (!DestPointer) {
1349  return TC_NotApplicable;
1350  }
1351 
1352  const PointerType *SrcPointer = SrcType->getAs<PointerType>();
1353  if (!SrcPointer) {
1354  msg = diag::err_bad_static_cast_pointer_nonpointer;
1355  return TC_NotApplicable;
1356  }
1357 
1358  return TryStaticDowncast(Self,
1359  Self.Context.getCanonicalType(SrcPointer->getPointeeType()),
1360  Self.Context.getCanonicalType(DestPointer->getPointeeType()),
1361  CStyle, OpRange, SrcType, DestType, msg, Kind,
1362  BasePath);
1363 }
1364 
1365 /// TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and
1366 /// TryStaticPointerDowncast. Tests whether a static downcast from SrcType to
1367 /// DestType is possible and allowed.
1370  bool CStyle, SourceRange OpRange, QualType OrigSrcType,
1371  QualType OrigDestType, unsigned &msg,
1372  CastKind &Kind, CXXCastPath &BasePath) {
1373  // We can only work with complete types. But don't complain if it doesn't work
1374  if (!Self.isCompleteType(OpRange.getBegin(), SrcType) ||
1375  !Self.isCompleteType(OpRange.getBegin(), DestType))
1376  return TC_NotApplicable;
1377 
1378  // Downcast can only happen in class hierarchies, so we need classes.
1379  if (!DestType->getAs<RecordType>() || !SrcType->getAs<RecordType>()) {
1380  return TC_NotApplicable;
1381  }
1382 
1383  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1384  /*DetectVirtual=*/true);
1385  if (!Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths)) {
1386  return TC_NotApplicable;
1387  }
1388 
1389  // Target type does derive from source type. Now we're serious. If an error
1390  // appears now, it's not ignored.
1391  // This may not be entirely in line with the standard. Take for example:
1392  // struct A {};
1393  // struct B : virtual A {
1394  // B(A&);
1395  // };
1396  //
1397  // void f()
1398  // {
1399  // (void)static_cast<const B&>(*((A*)0));
1400  // }
1401  // As far as the standard is concerned, p5 does not apply (A is virtual), so
1402  // p2 should be used instead - "const B& t(*((A*)0));" is perfectly valid.
1403  // However, both GCC and Comeau reject this example, and accepting it would
1404  // mean more complex code if we're to preserve the nice error message.
1405  // FIXME: Being 100% compliant here would be nice to have.
1406 
1407  // Must preserve cv, as always, unless we're in C-style mode.
1408  if (!CStyle && !DestType.isAtLeastAsQualifiedAs(SrcType)) {
1409  msg = diag::err_bad_cxx_cast_qualifiers_away;
1410  return TC_Failed;
1411  }
1412 
1413  if (Paths.isAmbiguous(SrcType.getUnqualifiedType())) {
1414  // This code is analoguous to that in CheckDerivedToBaseConversion, except
1415  // that it builds the paths in reverse order.
1416  // To sum up: record all paths to the base and build a nice string from
1417  // them. Use it to spice up the error message.
1418  if (!Paths.isRecordingPaths()) {
1419  Paths.clear();
1420  Paths.setRecordingPaths(true);
1421  Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths);
1422  }
1423  std::string PathDisplayStr;
1424  std::set<unsigned> DisplayedPaths;
1425  for (clang::CXXBasePath &Path : Paths) {
1426  if (DisplayedPaths.insert(Path.back().SubobjectNumber).second) {
1427  // We haven't displayed a path to this particular base
1428  // class subobject yet.
1429  PathDisplayStr += "\n ";
1430  for (CXXBasePathElement &PE : llvm::reverse(Path))
1431  PathDisplayStr += PE.Base->getType().getAsString() + " -> ";
1432  PathDisplayStr += QualType(DestType).getAsString();
1433  }
1434  }
1435 
1436  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_base_to_derived_cast)
1437  << QualType(SrcType).getUnqualifiedType()
1438  << QualType(DestType).getUnqualifiedType()
1439  << PathDisplayStr << OpRange;
1440  msg = 0;
1441  return TC_Failed;
1442  }
1443 
1444  if (Paths.getDetectedVirtual() != nullptr) {
1445  QualType VirtualBase(Paths.getDetectedVirtual(), 0);
1446  Self.Diag(OpRange.getBegin(), diag::err_static_downcast_via_virtual)
1447  << OrigSrcType << OrigDestType << VirtualBase << OpRange;
1448  msg = 0;
1449  return TC_Failed;
1450  }
1451 
1452  if (!CStyle) {
1453  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1454  SrcType, DestType,
1455  Paths.front(),
1456  diag::err_downcast_from_inaccessible_base)) {
1457  case Sema::AR_accessible:
1458  case Sema::AR_delayed: // be optimistic
1459  case Sema::AR_dependent: // be optimistic
1460  break;
1461 
1462  case Sema::AR_inaccessible:
1463  msg = 0;
1464  return TC_Failed;
1465  }
1466  }
1467 
1468  Self.BuildBasePathArray(Paths, BasePath);
1469  Kind = CK_BaseToDerived;
1470  return TC_Success;
1471 }
1472 
1473 /// TryStaticMemberPointerUpcast - Tests whether a conversion according to
1474 /// C++ 5.2.9p9 is valid:
1475 ///
1476 /// An rvalue of type "pointer to member of D of type cv1 T" can be
1477 /// converted to an rvalue of type "pointer to member of B of type cv2 T",
1478 /// where B is a base class of D [...].
1479 ///
1482  QualType DestType, bool CStyle,
1483  SourceRange OpRange,
1484  unsigned &msg, CastKind &Kind,
1485  CXXCastPath &BasePath) {
1486  const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>();
1487  if (!DestMemPtr)
1488  return TC_NotApplicable;
1489 
1490  bool WasOverloadedFunction = false;
1491  DeclAccessPair FoundOverload;
1492  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1493  if (FunctionDecl *Fn
1494  = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(), DestType, false,
1495  FoundOverload)) {
1496  CXXMethodDecl *M = cast<CXXMethodDecl>(Fn);
1497  SrcType = Self.Context.getMemberPointerType(Fn->getType(),
1498  Self.Context.getTypeDeclType(M->getParent()).getTypePtr());
1499  WasOverloadedFunction = true;
1500  }
1501  }
1502 
1503  const MemberPointerType *SrcMemPtr = SrcType->getAs<MemberPointerType>();
1504  if (!SrcMemPtr) {
1505  msg = diag::err_bad_static_cast_member_pointer_nonmp;
1506  return TC_NotApplicable;
1507  }
1508 
1509  // Lock down the inheritance model right now in MS ABI, whether or not the
1510  // pointee types are the same.
1511  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1512  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
1513  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
1514  }
1515 
1516  // T == T, modulo cv
1517  if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
1518  DestMemPtr->getPointeeType()))
1519  return TC_NotApplicable;
1520 
1521  // B base of D
1522  QualType SrcClass(SrcMemPtr->getClass(), 0);
1523  QualType DestClass(DestMemPtr->getClass(), 0);
1524  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1525  /*DetectVirtual=*/true);
1526  if (!Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths))
1527  return TC_NotApplicable;
1528 
1529  // B is a base of D. But is it an allowed base? If not, it's a hard error.
1530  if (Paths.isAmbiguous(Self.Context.getCanonicalType(DestClass))) {
1531  Paths.clear();
1532  Paths.setRecordingPaths(true);
1533  bool StillOkay =
1534  Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths);
1535  assert(StillOkay);
1536  (void)StillOkay;
1537  std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
1538  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
1539  << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
1540  msg = 0;
1541  return TC_Failed;
1542  }
1543 
1544  if (const RecordType *VBase = Paths.getDetectedVirtual()) {
1545  Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
1546  << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
1547  msg = 0;
1548  return TC_Failed;
1549  }
1550 
1551  if (!CStyle) {
1552  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1553  DestClass, SrcClass,
1554  Paths.front(),
1555  diag::err_upcast_to_inaccessible_base)) {
1556  case Sema::AR_accessible:
1557  case Sema::AR_delayed:
1558  case Sema::AR_dependent:
1559  // Optimistically assume that the delayed and dependent cases
1560  // will work out.
1561  break;
1562 
1563  case Sema::AR_inaccessible:
1564  msg = 0;
1565  return TC_Failed;
1566  }
1567  }
1568 
1569  if (WasOverloadedFunction) {
1570  // Resolve the address of the overloaded function again, this time
1571  // allowing complaints if something goes wrong.
1573  DestType,
1574  true,
1575  FoundOverload);
1576  if (!Fn) {
1577  msg = 0;
1578  return TC_Failed;
1579  }
1580 
1581  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr, FoundOverload, Fn);
1582  if (!SrcExpr.isUsable()) {
1583  msg = 0;
1584  return TC_Failed;
1585  }
1586  }
1587 
1588  Self.BuildBasePathArray(Paths, BasePath);
1589  Kind = CK_DerivedToBaseMemberPointer;
1590  return TC_Success;
1591 }
1592 
1593 /// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
1594 /// is valid:
1595 ///
1596 /// An expression e can be explicitly converted to a type T using a
1597 /// @c static_cast if the declaration "T t(e);" is well-formed [...].
1599 TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType,
1601  SourceRange OpRange, unsigned &msg,
1602  CastKind &Kind, bool ListInitialization) {
1603  if (DestType->isRecordType()) {
1604  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
1605  diag::err_bad_dynamic_cast_incomplete) ||
1606  Self.RequireNonAbstractType(OpRange.getBegin(), DestType,
1607  diag::err_allocation_of_abstract_type)) {
1608  msg = 0;
1609  return TC_Failed;
1610  }
1611  }
1612 
1614  InitializationKind InitKind
1615  = (CCK == Sema::CCK_CStyleCast)
1616  ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange,
1617  ListInitialization)
1618  : (CCK == Sema::CCK_FunctionalCast)
1619  ? InitializationKind::CreateFunctionalCast(OpRange, ListInitialization)
1620  : InitializationKind::CreateCast(OpRange);
1621  Expr *SrcExprRaw = SrcExpr.get();
1622  // FIXME: Per DR242, we should check for an implicit conversion sequence
1623  // or for a constructor that could be invoked by direct-initialization
1624  // here, not for an initialization sequence.
1625  InitializationSequence InitSeq(Self, Entity, InitKind, SrcExprRaw);
1626 
1627  // At this point of CheckStaticCast, if the destination is a reference,
1628  // or the expression is an overload expression this has to work.
1629  // There is no other way that works.
1630  // On the other hand, if we're checking a C-style cast, we've still got
1631  // the reinterpret_cast way.
1632  bool CStyle
1633  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1634  if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType()))
1635  return TC_NotApplicable;
1636 
1637  ExprResult Result = InitSeq.Perform(Self, Entity, InitKind, SrcExprRaw);
1638  if (Result.isInvalid()) {
1639  msg = 0;
1640  return TC_Failed;
1641  }
1642 
1643  if (InitSeq.isConstructorInitialization())
1644  Kind = CK_ConstructorConversion;
1645  else
1646  Kind = CK_NoOp;
1647 
1648  SrcExpr = Result;
1649  return TC_Success;
1650 }
1651 
1652 /// TryConstCast - See if a const_cast from source to destination is allowed,
1653 /// and perform it if it is.
1655  QualType DestType, bool CStyle,
1656  unsigned &msg) {
1657  DestType = Self.Context.getCanonicalType(DestType);
1658  QualType SrcType = SrcExpr.get()->getType();
1659  bool NeedToMaterializeTemporary = false;
1660 
1661  if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
1662  // C++11 5.2.11p4:
1663  // if a pointer to T1 can be explicitly converted to the type "pointer to
1664  // T2" using a const_cast, then the following conversions can also be
1665  // made:
1666  // -- an lvalue of type T1 can be explicitly converted to an lvalue of
1667  // type T2 using the cast const_cast<T2&>;
1668  // -- a glvalue of type T1 can be explicitly converted to an xvalue of
1669  // type T2 using the cast const_cast<T2&&>; and
1670  // -- if T1 is a class type, a prvalue of type T1 can be explicitly
1671  // converted to an xvalue of type T2 using the cast const_cast<T2&&>.
1672 
1673  if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr.get()->isLValue()) {
1674  // Cannot const_cast non-lvalue to lvalue reference type. But if this
1675  // is C-style, static_cast might find a way, so we simply suggest a
1676  // message and tell the parent to keep searching.
1677  msg = diag::err_bad_cxx_cast_rvalue;
1678  return TC_NotApplicable;
1679  }
1680 
1681  if (isa<RValueReferenceType>(DestTypeTmp) && SrcExpr.get()->isRValue()) {
1682  if (!SrcType->isRecordType()) {
1683  // Cannot const_cast non-class prvalue to rvalue reference type. But if
1684  // this is C-style, static_cast can do this.
1685  msg = diag::err_bad_cxx_cast_rvalue;
1686  return TC_NotApplicable;
1687  }
1688 
1689  // Materialize the class prvalue so that the const_cast can bind a
1690  // reference to it.
1691  NeedToMaterializeTemporary = true;
1692  }
1693 
1694  // It's not completely clear under the standard whether we can
1695  // const_cast bit-field gl-values. Doing so would not be
1696  // intrinsically complicated, but for now, we say no for
1697  // consistency with other compilers and await the word of the
1698  // committee.
1699  if (SrcExpr.get()->refersToBitField()) {
1700  msg = diag::err_bad_cxx_cast_bitfield;
1701  return TC_NotApplicable;
1702  }
1703 
1704  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
1705  SrcType = Self.Context.getPointerType(SrcType);
1706  }
1707 
1708  // C++ 5.2.11p5: For a const_cast involving pointers to data members [...]
1709  // the rules for const_cast are the same as those used for pointers.
1710 
1711  if (!DestType->isPointerType() &&
1712  !DestType->isMemberPointerType() &&
1713  !DestType->isObjCObjectPointerType()) {
1714  // Cannot cast to non-pointer, non-reference type. Note that, if DestType
1715  // was a reference type, we converted it to a pointer above.
1716  // The status of rvalue references isn't entirely clear, but it looks like
1717  // conversion to them is simply invalid.
1718  // C++ 5.2.11p3: For two pointer types [...]
1719  if (!CStyle)
1720  msg = diag::err_bad_const_cast_dest;
1721  return TC_NotApplicable;
1722  }
1723  if (DestType->isFunctionPointerType() ||
1724  DestType->isMemberFunctionPointerType()) {
1725  // Cannot cast direct function pointers.
1726  // C++ 5.2.11p2: [...] where T is any object type or the void type [...]
1727  // T is the ultimate pointee of source and target type.
1728  if (!CStyle)
1729  msg = diag::err_bad_const_cast_dest;
1730  return TC_NotApplicable;
1731  }
1732 
1733  // C++ [expr.const.cast]p3:
1734  // "For two similar types T1 and T2, [...]"
1735  //
1736  // We only allow a const_cast to change cvr-qualifiers, not other kinds of
1737  // type qualifiers. (Likewise, we ignore other changes when determining
1738  // whether a cast casts away constness.)
1739  if (!Self.Context.hasCvrSimilarType(SrcType, DestType))
1740  return TC_NotApplicable;
1741 
1742  if (NeedToMaterializeTemporary)
1743  // This is a const_cast from a class prvalue to an rvalue reference type.
1744  // Materialize a temporary to store the result of the conversion.
1745  SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcExpr.get()->getType(),
1746  SrcExpr.get(),
1747  /*IsLValueReference*/ false);
1748 
1749  return TC_Success;
1750 }
1751 
1752 // Checks for undefined behavior in reinterpret_cast.
1753 // The cases that is checked for is:
1754 // *reinterpret_cast<T*>(&a)
1755 // reinterpret_cast<T&>(a)
1756 // where accessing 'a' as type 'T' will result in undefined behavior.
1758  bool IsDereference,
1759  SourceRange Range) {
1760  unsigned DiagID = IsDereference ?
1761  diag::warn_pointer_indirection_from_incompatible_type :
1762  diag::warn_undefined_reinterpret_cast;
1763 
1764  if (Diags.isIgnored(DiagID, Range.getBegin()))
1765  return;
1766 
1767  QualType SrcTy, DestTy;
1768  if (IsDereference) {
1769  if (!SrcType->getAs<PointerType>() || !DestType->getAs<PointerType>()) {
1770  return;
1771  }
1772  SrcTy = SrcType->getPointeeType();
1773  DestTy = DestType->getPointeeType();
1774  } else {
1775  if (!DestType->getAs<ReferenceType>()) {
1776  return;
1777  }
1778  SrcTy = SrcType;
1779  DestTy = DestType->getPointeeType();
1780  }
1781 
1782  // Cast is compatible if the types are the same.
1783  if (Context.hasSameUnqualifiedType(DestTy, SrcTy)) {
1784  return;
1785  }
1786  // or one of the types is a char or void type
1787  if (DestTy->isAnyCharacterType() || DestTy->isVoidType() ||
1788  SrcTy->isAnyCharacterType() || SrcTy->isVoidType()) {
1789  return;
1790  }
1791  // or one of the types is a tag type.
1792  if (SrcTy->getAs<TagType>() || DestTy->getAs<TagType>()) {
1793  return;
1794  }
1795 
1796  // FIXME: Scoped enums?
1797  if ((SrcTy->isUnsignedIntegerType() && DestTy->isSignedIntegerType()) ||
1798  (SrcTy->isSignedIntegerType() && DestTy->isUnsignedIntegerType())) {
1799  if (Context.getTypeSize(DestTy) == Context.getTypeSize(SrcTy)) {
1800  return;
1801  }
1802  }
1803 
1804  Diag(Range.getBegin(), DiagID) << SrcType << DestType << Range;
1805 }
1806 
1807 static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr,
1808  QualType DestType) {
1809  QualType SrcType = SrcExpr.get()->getType();
1810  if (Self.Context.hasSameType(SrcType, DestType))
1811  return;
1812  if (const PointerType *SrcPtrTy = SrcType->getAs<PointerType>())
1813  if (SrcPtrTy->isObjCSelType()) {
1814  QualType DT = DestType;
1815  if (isa<PointerType>(DestType))
1816  DT = DestType->getPointeeType();
1817  if (!DT.getUnqualifiedType()->isVoidType())
1818  Self.Diag(SrcExpr.get()->getExprLoc(),
1819  diag::warn_cast_pointer_from_sel)
1820  << SrcType << DestType << SrcExpr.get()->getSourceRange();
1821  }
1822 }
1823 
1824 /// Diagnose casts that change the calling convention of a pointer to a function
1825 /// defined in the current TU.
1826 static void DiagnoseCallingConvCast(Sema &Self, const ExprResult &SrcExpr,
1827  QualType DstType, SourceRange OpRange) {
1828  // Check if this cast would change the calling convention of a function
1829  // pointer type.
1830  QualType SrcType = SrcExpr.get()->getType();
1831  if (Self.Context.hasSameType(SrcType, DstType) ||
1832  !SrcType->isFunctionPointerType() || !DstType->isFunctionPointerType())
1833  return;
1834  const auto *SrcFTy =
1835  SrcType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
1836  const auto *DstFTy =
1837  DstType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
1838  CallingConv SrcCC = SrcFTy->getCallConv();
1839  CallingConv DstCC = DstFTy->getCallConv();
1840  if (SrcCC == DstCC)
1841  return;
1842 
1843  // We have a calling convention cast. Check if the source is a pointer to a
1844  // known, specific function that has already been defined.
1845  Expr *Src = SrcExpr.get()->IgnoreParenImpCasts();
1846  if (auto *UO = dyn_cast<UnaryOperator>(Src))
1847  if (UO->getOpcode() == UO_AddrOf)
1848  Src = UO->getSubExpr()->IgnoreParenImpCasts();
1849  auto *DRE = dyn_cast<DeclRefExpr>(Src);
1850  if (!DRE)
1851  return;
1852  auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
1853  if (!FD)
1854  return;
1855 
1856  // Only warn if we are casting from the default convention to a non-default
1857  // convention. This can happen when the programmer forgot to apply the calling
1858  // convention to the function declaration and then inserted this cast to
1859  // satisfy the type system.
1861  FD->isVariadic(), FD->isCXXInstanceMember());
1862  if (DstCC == DefaultCC || SrcCC != DefaultCC)
1863  return;
1864 
1865  // Diagnose this cast, as it is probably bad.
1866  StringRef SrcCCName = FunctionType::getNameForCallConv(SrcCC);
1867  StringRef DstCCName = FunctionType::getNameForCallConv(DstCC);
1868  Self.Diag(OpRange.getBegin(), diag::warn_cast_calling_conv)
1869  << SrcCCName << DstCCName << OpRange;
1870 
1871  // The checks above are cheaper than checking if the diagnostic is enabled.
1872  // However, it's worth checking if the warning is enabled before we construct
1873  // a fixit.
1874  if (Self.Diags.isIgnored(diag::warn_cast_calling_conv, OpRange.getBegin()))
1875  return;
1876 
1877  // Try to suggest a fixit to change the calling convention of the function
1878  // whose address was taken. Try to use the latest macro for the convention.
1879  // For example, users probably want to write "WINAPI" instead of "__stdcall"
1880  // to match the Windows header declarations.
1881  SourceLocation NameLoc = FD->getFirstDecl()->getNameInfo().getLoc();
1882  Preprocessor &PP = Self.getPreprocessor();
1883  SmallVector<TokenValue, 6> AttrTokens;
1884  SmallString<64> CCAttrText;
1885  llvm::raw_svector_ostream OS(CCAttrText);
1886  if (Self.getLangOpts().MicrosoftExt) {
1887  // __stdcall or __vectorcall
1888  OS << "__" << DstCCName;
1889  IdentifierInfo *II = PP.getIdentifierInfo(OS.str());
1890  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
1891  ? TokenValue(II->getTokenID())
1892  : TokenValue(II));
1893  } else {
1894  // __attribute__((stdcall)) or __attribute__((vectorcall))
1895  OS << "__attribute__((" << DstCCName << "))";
1896  AttrTokens.push_back(tok::kw___attribute);
1897  AttrTokens.push_back(tok::l_paren);
1898  AttrTokens.push_back(tok::l_paren);
1899  IdentifierInfo *II = PP.getIdentifierInfo(DstCCName);
1900  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
1901  ? TokenValue(II->getTokenID())
1902  : TokenValue(II));
1903  AttrTokens.push_back(tok::r_paren);
1904  AttrTokens.push_back(tok::r_paren);
1905  }
1906  StringRef AttrSpelling = PP.getLastMacroWithSpelling(NameLoc, AttrTokens);
1907  if (!AttrSpelling.empty())
1908  CCAttrText = AttrSpelling;
1909  OS << ' ';
1910  Self.Diag(NameLoc, diag::note_change_calling_conv_fixit)
1911  << FD << DstCCName << FixItHint::CreateInsertion(NameLoc, CCAttrText);
1912 }
1913 
1914 static void checkIntToPointerCast(bool CStyle, SourceLocation Loc,
1915  const Expr *SrcExpr, QualType DestType,
1916  Sema &Self) {
1917  QualType SrcType = SrcExpr->getType();
1918 
1919  // Not warning on reinterpret_cast, boolean, constant expressions, etc
1920  // are not explicit design choices, but consistent with GCC's behavior.
1921  // Feel free to modify them if you've reason/evidence for an alternative.
1922  if (CStyle && SrcType->isIntegralType(Self.Context)
1923  && !SrcType->isBooleanType()
1924  && !SrcType->isEnumeralType()
1925  && !SrcExpr->isIntegerConstantExpr(Self.Context)
1926  && Self.Context.getTypeSize(DestType) >
1927  Self.Context.getTypeSize(SrcType)) {
1928  // Separate between casts to void* and non-void* pointers.
1929  // Some APIs use (abuse) void* for something like a user context,
1930  // and often that value is an integer even if it isn't a pointer itself.
1931  // Having a separate warning flag allows users to control the warning
1932  // for their workflow.
1933  unsigned Diag = DestType->isVoidPointerType() ?
1934  diag::warn_int_to_void_pointer_cast
1935  : diag::warn_int_to_pointer_cast;
1936  Self.Diag(Loc, Diag) << SrcType << DestType;
1937  }
1938 }
1939 
1940 static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType,
1941  ExprResult &Result) {
1942  // We can only fix an overloaded reinterpret_cast if
1943  // - it is a template with explicit arguments that resolves to an lvalue
1944  // unambiguously, or
1945  // - it is the only function in an overload set that may have its address
1946  // taken.
1947 
1948  Expr *E = Result.get();
1949  // TODO: what if this fails because of DiagnoseUseOfDecl or something
1950  // like it?
1952  Result,
1953  Expr::getValueKindForType(DestType) == VK_RValue // Convert Fun to Ptr
1954  ) &&
1955  Result.isUsable())
1956  return true;
1957 
1958  // No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
1959  // preserves Result.
1960  Result = E;
1962  Result, /*DoFunctionPointerConversion=*/true))
1963  return false;
1964  return Result.isUsable();
1965 }
1966 
1967 static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType) {
1968  return SrcType->isPointerType() && DestType->isPointerType() &&
1969  SrcType->getAs<PointerType>()->getPointeeType().getAddressSpace() !=
1970  DestType->getAs<PointerType>()->getPointeeType().getAddressSpace();
1971 }
1972 
1974  QualType DestType, bool CStyle,
1975  SourceRange OpRange,
1976  unsigned &msg,
1977  CastKind &Kind) {
1978  bool IsLValueCast = false;
1979 
1980  DestType = Self.Context.getCanonicalType(DestType);
1981  QualType SrcType = SrcExpr.get()->getType();
1982 
1983  // Is the source an overloaded name? (i.e. &foo)
1984  // If so, reinterpret_cast generally can not help us here (13.4, p1, bullet 5)
1985  if (SrcType == Self.Context.OverloadTy) {
1986  ExprResult FixedExpr = SrcExpr;
1987  if (!fixOverloadedReinterpretCastExpr(Self, DestType, FixedExpr))
1988  return TC_NotApplicable;
1989 
1990  assert(FixedExpr.isUsable() && "Invalid result fixing overloaded expr");
1991  SrcExpr = FixedExpr;
1992  SrcType = SrcExpr.get()->getType();
1993  }
1994 
1995  if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
1996  if (!SrcExpr.get()->isGLValue()) {
1997  // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
1998  // similar comment in const_cast.
1999  msg = diag::err_bad_cxx_cast_rvalue;
2000  return TC_NotApplicable;
2001  }
2002 
2003  if (!CStyle) {
2004  Self.CheckCompatibleReinterpretCast(SrcType, DestType,
2005  /*isDereference=*/false, OpRange);
2006  }
2007 
2008  // C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
2009  // same effect as the conversion *reinterpret_cast<T*>(&x) with the
2010  // built-in & and * operators.
2011 
2012  const char *inappropriate = nullptr;
2013  switch (SrcExpr.get()->getObjectKind()) {
2014  case OK_Ordinary:
2015  break;
2016  case OK_BitField:
2017  msg = diag::err_bad_cxx_cast_bitfield;
2018  return TC_NotApplicable;
2019  // FIXME: Use a specific diagnostic for the rest of these cases.
2020  case OK_VectorComponent: inappropriate = "vector element"; break;
2021  case OK_ObjCProperty: inappropriate = "property expression"; break;
2022  case OK_ObjCSubscript: inappropriate = "container subscripting expression";
2023  break;
2024  }
2025  if (inappropriate) {
2026  Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
2027  << inappropriate << DestType
2028  << OpRange << SrcExpr.get()->getSourceRange();
2029  msg = 0; SrcExpr = ExprError();
2030  return TC_NotApplicable;
2031  }
2032 
2033  // This code does this transformation for the checked types.
2034  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
2035  SrcType = Self.Context.getPointerType(SrcType);
2036 
2037  IsLValueCast = true;
2038  }
2039 
2040  // Canonicalize source for comparison.
2041  SrcType = Self.Context.getCanonicalType(SrcType);
2042 
2043  const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>(),
2044  *SrcMemPtr = SrcType->getAs<MemberPointerType>();
2045  if (DestMemPtr && SrcMemPtr) {
2046  // C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
2047  // can be explicitly converted to an rvalue of type "pointer to member
2048  // of Y of type T2" if T1 and T2 are both function types or both object
2049  // types.
2050  if (DestMemPtr->isMemberFunctionPointer() !=
2051  SrcMemPtr->isMemberFunctionPointer())
2052  return TC_NotApplicable;
2053 
2054  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2055  // We need to determine the inheritance model that the class will use if
2056  // haven't yet.
2057  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
2058  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
2059  }
2060 
2061  // Don't allow casting between member pointers of different sizes.
2062  if (Self.Context.getTypeSize(DestMemPtr) !=
2063  Self.Context.getTypeSize(SrcMemPtr)) {
2064  msg = diag::err_bad_cxx_cast_member_pointer_size;
2065  return TC_Failed;
2066  }
2067 
2068  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
2069  // constness.
2070  // A reinterpret_cast followed by a const_cast can, though, so in C-style,
2071  // we accept it.
2072  if (auto CACK =
2073  CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2074  /*CheckObjCLifetime=*/CStyle))
2075  return getCastAwayConstnessCastKind(CACK, msg);
2076 
2077  // A valid member pointer cast.
2078  assert(!IsLValueCast);
2079  Kind = CK_ReinterpretMemberPointer;
2080  return TC_Success;
2081  }
2082 
2083  // See below for the enumeral issue.
2084  if (SrcType->isNullPtrType() && DestType->isIntegralType(Self.Context)) {
2085  // C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
2086  // type large enough to hold it. A value of std::nullptr_t can be
2087  // converted to an integral type; the conversion has the same meaning
2088  // and validity as a conversion of (void*)0 to the integral type.
2089  if (Self.Context.getTypeSize(SrcType) >
2090  Self.Context.getTypeSize(DestType)) {
2091  msg = diag::err_bad_reinterpret_cast_small_int;
2092  return TC_Failed;
2093  }
2094  Kind = CK_PointerToIntegral;
2095  return TC_Success;
2096  }
2097 
2098  // Allow reinterpret_casts between vectors of the same size and
2099  // between vectors and integers of the same size.
2100  bool destIsVector = DestType->isVectorType();
2101  bool srcIsVector = SrcType->isVectorType();
2102  if (srcIsVector || destIsVector) {
2103  // The non-vector type, if any, must have integral type. This is
2104  // the same rule that C vector casts use; note, however, that enum
2105  // types are not integral in C++.
2106  if ((!destIsVector && !DestType->isIntegralType(Self.Context)) ||
2107  (!srcIsVector && !SrcType->isIntegralType(Self.Context)))
2108  return TC_NotApplicable;
2109 
2110  // The size we want to consider is eltCount * eltSize.
2111  // That's exactly what the lax-conversion rules will check.
2112  if (Self.areLaxCompatibleVectorTypes(SrcType, DestType)) {
2113  Kind = CK_BitCast;
2114  return TC_Success;
2115  }
2116 
2117  // Otherwise, pick a reasonable diagnostic.
2118  if (!destIsVector)
2119  msg = diag::err_bad_cxx_cast_vector_to_scalar_different_size;
2120  else if (!srcIsVector)
2121  msg = diag::err_bad_cxx_cast_scalar_to_vector_different_size;
2122  else
2123  msg = diag::err_bad_cxx_cast_vector_to_vector_different_size;
2124 
2125  return TC_Failed;
2126  }
2127 
2128  if (SrcType == DestType) {
2129  // C++ 5.2.10p2 has a note that mentions that, subject to all other
2130  // restrictions, a cast to the same type is allowed so long as it does not
2131  // cast away constness. In C++98, the intent was not entirely clear here,
2132  // since all other paragraphs explicitly forbid casts to the same type.
2133  // C++11 clarifies this case with p2.
2134  //
2135  // The only allowed types are: integral, enumeration, pointer, or
2136  // pointer-to-member types. We also won't restrict Obj-C pointers either.
2137  Kind = CK_NoOp;
2139  if (SrcType->isIntegralOrEnumerationType() ||
2140  SrcType->isAnyPointerType() ||
2141  SrcType->isMemberPointerType() ||
2142  SrcType->isBlockPointerType()) {
2143  Result = TC_Success;
2144  }
2145  return Result;
2146  }
2147 
2148  bool destIsPtr = DestType->isAnyPointerType() ||
2149  DestType->isBlockPointerType();
2150  bool srcIsPtr = SrcType->isAnyPointerType() ||
2151  SrcType->isBlockPointerType();
2152  if (!destIsPtr && !srcIsPtr) {
2153  // Except for std::nullptr_t->integer and lvalue->reference, which are
2154  // handled above, at least one of the two arguments must be a pointer.
2155  return TC_NotApplicable;
2156  }
2157 
2158  if (DestType->isIntegralType(Self.Context)) {
2159  assert(srcIsPtr && "One type must be a pointer");
2160  // C++ 5.2.10p4: A pointer can be explicitly converted to any integral
2161  // type large enough to hold it; except in Microsoft mode, where the
2162  // integral type size doesn't matter (except we don't allow bool).
2163  bool MicrosoftException = Self.getLangOpts().MicrosoftExt &&
2164  !DestType->isBooleanType();
2165  if ((Self.Context.getTypeSize(SrcType) >
2166  Self.Context.getTypeSize(DestType)) &&
2167  !MicrosoftException) {
2168  msg = diag::err_bad_reinterpret_cast_small_int;
2169  return TC_Failed;
2170  }
2171  Kind = CK_PointerToIntegral;
2172  return TC_Success;
2173  }
2174 
2175  if (SrcType->isIntegralOrEnumerationType()) {
2176  assert(destIsPtr && "One type must be a pointer");
2177  checkIntToPointerCast(CStyle, OpRange.getBegin(), SrcExpr.get(), DestType,
2178  Self);
2179  // C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
2180  // converted to a pointer.
2181  // C++ 5.2.10p9: [Note: ...a null pointer constant of integral type is not
2182  // necessarily converted to a null pointer value.]
2183  Kind = CK_IntegralToPointer;
2184  return TC_Success;
2185  }
2186 
2187  if (!destIsPtr || !srcIsPtr) {
2188  // With the valid non-pointer conversions out of the way, we can be even
2189  // more stringent.
2190  return TC_NotApplicable;
2191  }
2192 
2193  // Cannot convert between block pointers and Objective-C object pointers.
2194  if ((SrcType->isBlockPointerType() && DestType->isObjCObjectPointerType()) ||
2195  (DestType->isBlockPointerType() && SrcType->isObjCObjectPointerType()))
2196  return TC_NotApplicable;
2197 
2198  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
2199  // The C-style cast operator can.
2200  TryCastResult SuccessResult = TC_Success;
2201  if (auto CACK =
2202  CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2203  /*CheckObjCLifetime=*/CStyle))
2204  SuccessResult = getCastAwayConstnessCastKind(CACK, msg);
2205 
2206  if (IsLValueCast) {
2207  Kind = CK_LValueBitCast;
2208  } else if (DestType->isObjCObjectPointerType()) {
2209  Kind = Self.PrepareCastToObjCObjectPointer(SrcExpr);
2210  } else if (DestType->isBlockPointerType()) {
2211  if (!SrcType->isBlockPointerType()) {
2212  Kind = CK_AnyPointerToBlockPointerCast;
2213  } else {
2214  Kind = CK_BitCast;
2215  }
2216  } else if (IsAddressSpaceConversion(SrcType, DestType)) {
2217  Kind = CK_AddressSpaceConversion;
2218  } else {
2219  Kind = CK_BitCast;
2220  }
2221 
2222  // Any pointer can be cast to an Objective-C pointer type with a C-style
2223  // cast.
2224  if (CStyle && DestType->isObjCObjectPointerType()) {
2225  return SuccessResult;
2226  }
2227  if (CStyle)
2228  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2229 
2230  DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
2231 
2232  // Not casting away constness, so the only remaining check is for compatible
2233  // pointer categories.
2234 
2235  if (SrcType->isFunctionPointerType()) {
2236  if (DestType->isFunctionPointerType()) {
2237  // C++ 5.2.10p6: A pointer to a function can be explicitly converted to
2238  // a pointer to a function of a different type.
2239  return SuccessResult;
2240  }
2241 
2242  // C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
2243  // an object type or vice versa is conditionally-supported.
2244  // Compilers support it in C++03 too, though, because it's necessary for
2245  // casting the return value of dlsym() and GetProcAddress().
2246  // FIXME: Conditionally-supported behavior should be configurable in the
2247  // TargetInfo or similar.
2248  Self.Diag(OpRange.getBegin(),
2249  Self.getLangOpts().CPlusPlus11 ?
2250  diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2251  << OpRange;
2252  return SuccessResult;
2253  }
2254 
2255  if (DestType->isFunctionPointerType()) {
2256  // See above.
2257  Self.Diag(OpRange.getBegin(),
2258  Self.getLangOpts().CPlusPlus11 ?
2259  diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2260  << OpRange;
2261  return SuccessResult;
2262  }
2263 
2264  // C++ 5.2.10p7: A pointer to an object can be explicitly converted to
2265  // a pointer to an object of different type.
2266  // Void pointers are not specified, but supported by every compiler out there.
2267  // So we finish by allowing everything that remains - it's got to be two
2268  // object pointers.
2269  return SuccessResult;
2270 }
2271 
2272 void CastOperation::CheckCXXCStyleCast(bool FunctionalStyle,
2273  bool ListInitialization) {
2274  assert(Self.getLangOpts().CPlusPlus);
2275 
2276  // Handle placeholders.
2277  if (isPlaceholder()) {
2278  // C-style casts can resolve __unknown_any types.
2279  if (claimPlaceholder(BuiltinType::UnknownAny)) {
2280  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2281  SrcExpr.get(), Kind,
2282  ValueKind, BasePath);
2283  return;
2284  }
2285 
2286  checkNonOverloadPlaceholders();
2287  if (SrcExpr.isInvalid())
2288  return;
2289  }
2290 
2291  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
2292  // This test is outside everything else because it's the only case where
2293  // a non-lvalue-reference target type does not lead to decay.
2294  if (DestType->isVoidType()) {
2295  Kind = CK_ToVoid;
2296 
2297  if (claimPlaceholder(BuiltinType::Overload)) {
2299  SrcExpr, /* Decay Function to ptr */ false,
2300  /* Complain */ true, DestRange, DestType,
2301  diag::err_bad_cstyle_cast_overload);
2302  if (SrcExpr.isInvalid())
2303  return;
2304  }
2305 
2306  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2307  return;
2308  }
2309 
2310  // If the type is dependent, we won't do any other semantic analysis now.
2311  if (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
2312  SrcExpr.get()->isValueDependent()) {
2313  assert(Kind == CK_Dependent);
2314  return;
2315  }
2316 
2317  if (ValueKind == VK_RValue && !DestType->isRecordType() &&
2318  !isPlaceholder(BuiltinType::Overload)) {
2319  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2320  if (SrcExpr.isInvalid())
2321  return;
2322  }
2323 
2324  // AltiVec vector initialization with a single literal.
2325  if (const VectorType *vecTy = DestType->getAs<VectorType>())
2326  if (vecTy->getVectorKind() == VectorType::AltiVecVector
2327  && (SrcExpr.get()->getType()->isIntegerType()
2328  || SrcExpr.get()->getType()->isFloatingType())) {
2329  Kind = CK_VectorSplat;
2330  SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2331  return;
2332  }
2333 
2334  // C++ [expr.cast]p5: The conversions performed by
2335  // - a const_cast,
2336  // - a static_cast,
2337  // - a static_cast followed by a const_cast,
2338  // - a reinterpret_cast, or
2339  // - a reinterpret_cast followed by a const_cast,
2340  // can be performed using the cast notation of explicit type conversion.
2341  // [...] If a conversion can be interpreted in more than one of the ways
2342  // listed above, the interpretation that appears first in the list is used,
2343  // even if a cast resulting from that interpretation is ill-formed.
2344  // In plain language, this means trying a const_cast ...
2345  unsigned msg = diag::err_bad_cxx_cast_generic;
2346  TryCastResult tcr = TryConstCast(Self, SrcExpr, DestType,
2347  /*CStyle*/true, msg);
2348  if (SrcExpr.isInvalid())
2349  return;
2350  if (isValidCast(tcr))
2351  Kind = CK_NoOp;
2352 
2354  = FunctionalStyle? Sema::CCK_FunctionalCast
2356  if (tcr == TC_NotApplicable) {
2357  // ... or if that is not possible, a static_cast, ignoring const, ...
2358  tcr = TryStaticCast(Self, SrcExpr, DestType, CCK, OpRange,
2359  msg, Kind, BasePath, ListInitialization);
2360  if (SrcExpr.isInvalid())
2361  return;
2362 
2363  if (tcr == TC_NotApplicable) {
2364  // ... and finally a reinterpret_cast, ignoring const.
2365  tcr = TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/true,
2366  OpRange, msg, Kind);
2367  if (SrcExpr.isInvalid())
2368  return;
2369  }
2370  }
2371 
2373  isValidCast(tcr))
2374  checkObjCConversion(CCK);
2375 
2376  if (tcr != TC_Success && msg != 0) {
2377  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2378  DeclAccessPair Found;
2380  DestType,
2381  /*Complain*/ true,
2382  Found);
2383  if (Fn) {
2384  // If DestType is a function type (not to be confused with the function
2385  // pointer type), it will be possible to resolve the function address,
2386  // but the type cast should be considered as failure.
2387  OverloadExpr *OE = OverloadExpr::find(SrcExpr.get()).Expression;
2388  Self.Diag(OpRange.getBegin(), diag::err_bad_cstyle_cast_overload)
2389  << OE->getName() << DestType << OpRange
2390  << OE->getQualifierLoc().getSourceRange();
2391  Self.NoteAllOverloadCandidates(SrcExpr.get());
2392  }
2393  } else {
2394  diagnoseBadCast(Self, msg, (FunctionalStyle ? CT_Functional : CT_CStyle),
2395  OpRange, SrcExpr.get(), DestType, ListInitialization);
2396  }
2397  }
2398 
2399  if (isValidCast(tcr)) {
2400  if (Kind == CK_BitCast)
2401  checkCastAlign();
2402  } else {
2403  SrcExpr = ExprError();
2404  }
2405 }
2406 
2407 /// DiagnoseBadFunctionCast - Warn whenever a function call is cast to a
2408 /// non-matching type. Such as enum function call to int, int call to
2409 /// pointer; etc. Cast to 'void' is an exception.
2410 static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr,
2411  QualType DestType) {
2412  if (Self.Diags.isIgnored(diag::warn_bad_function_cast,
2413  SrcExpr.get()->getExprLoc()))
2414  return;
2415 
2416  if (!isa<CallExpr>(SrcExpr.get()))
2417  return;
2418 
2419  QualType SrcType = SrcExpr.get()->getType();
2420  if (DestType.getUnqualifiedType()->isVoidType())
2421  return;
2422  if ((SrcType->isAnyPointerType() || SrcType->isBlockPointerType())
2423  && (DestType->isAnyPointerType() || DestType->isBlockPointerType()))
2424  return;
2425  if (SrcType->isIntegerType() && DestType->isIntegerType() &&
2426  (SrcType->isBooleanType() == DestType->isBooleanType()) &&
2427  (SrcType->isEnumeralType() == DestType->isEnumeralType()))
2428  return;
2429  if (SrcType->isRealFloatingType() && DestType->isRealFloatingType())
2430  return;
2431  if (SrcType->isEnumeralType() && DestType->isEnumeralType())
2432  return;
2433  if (SrcType->isComplexType() && DestType->isComplexType())
2434  return;
2435  if (SrcType->isComplexIntegerType() && DestType->isComplexIntegerType())
2436  return;
2437 
2438  Self.Diag(SrcExpr.get()->getExprLoc(),
2439  diag::warn_bad_function_cast)
2440  << SrcType << DestType << SrcExpr.get()->getSourceRange();
2441 }
2442 
2443 /// Check the semantics of a C-style cast operation, in C.
2444 void CastOperation::CheckCStyleCast() {
2445  assert(!Self.getLangOpts().CPlusPlus);
2446 
2447  // C-style casts can resolve __unknown_any types.
2448  if (claimPlaceholder(BuiltinType::UnknownAny)) {
2449  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2450  SrcExpr.get(), Kind,
2451  ValueKind, BasePath);
2452  return;
2453  }
2454 
2455  // C99 6.5.4p2: the cast type needs to be void or scalar and the expression
2456  // type needs to be scalar.
2457  if (DestType->isVoidType()) {
2458  // We don't necessarily do lvalue-to-rvalue conversions on this.
2459  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2460  if (SrcExpr.isInvalid())
2461  return;
2462 
2463  // Cast to void allows any expr type.
2464  Kind = CK_ToVoid;
2465  return;
2466  }
2467 
2468  // Overloads are allowed with C extensions, so we need to support them.
2469  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2470  DeclAccessPair DAP;
2472  SrcExpr.get(), DestType, /*Complain=*/true, DAP))
2473  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr.get(), DAP, FD);
2474  else
2475  return;
2476  assert(SrcExpr.isUsable());
2477  }
2478  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2479  if (SrcExpr.isInvalid())
2480  return;
2481  QualType SrcType = SrcExpr.get()->getType();
2482 
2483  assert(!SrcType->isPlaceholderType());
2484 
2485  // OpenCL v1 s6.5: Casting a pointer to address space A to a pointer to
2486  // address space B is illegal.
2487  if (Self.getLangOpts().OpenCL && DestType->isPointerType() &&
2488  SrcType->isPointerType()) {
2489  const PointerType *DestPtr = DestType->getAs<PointerType>();
2490  if (!DestPtr->isAddressSpaceOverlapping(*SrcType->getAs<PointerType>())) {
2491  Self.Diag(OpRange.getBegin(),
2492  diag::err_typecheck_incompatible_address_space)
2493  << SrcType << DestType << Sema::AA_Casting
2494  << SrcExpr.get()->getSourceRange();
2495  SrcExpr = ExprError();
2496  return;
2497  }
2498  }
2499 
2500  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
2501  diag::err_typecheck_cast_to_incomplete)) {
2502  SrcExpr = ExprError();
2503  return;
2504  }
2505 
2506  if (!DestType->isScalarType() && !DestType->isVectorType()) {
2507  const RecordType *DestRecordTy = DestType->getAs<RecordType>();
2508 
2509  if (DestRecordTy && Self.Context.hasSameUnqualifiedType(DestType, SrcType)){
2510  // GCC struct/union extension: allow cast to self.
2511  Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_nonscalar)
2512  << DestType << SrcExpr.get()->getSourceRange();
2513  Kind = CK_NoOp;
2514  return;
2515  }
2516 
2517  // GCC's cast to union extension.
2518  if (DestRecordTy && DestRecordTy->getDecl()->isUnion()) {
2519  RecordDecl *RD = DestRecordTy->getDecl();
2520  if (CastExpr::getTargetFieldForToUnionCast(RD, SrcType)) {
2521  Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_to_union)
2522  << SrcExpr.get()->getSourceRange();
2523  Kind = CK_ToUnion;
2524  return;
2525  } else {
2526  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cast_to_union_no_type)
2527  << SrcType << SrcExpr.get()->getSourceRange();
2528  SrcExpr = ExprError();
2529  return;
2530  }
2531  }
2532 
2533  // OpenCL v2.0 s6.13.10 - Allow casts from '0' to event_t type.
2534  if (Self.getLangOpts().OpenCL && DestType->isEventT()) {
2535  llvm::APSInt CastInt;
2536  if (SrcExpr.get()->EvaluateAsInt(CastInt, Self.Context)) {
2537  if (0 == CastInt) {
2538  Kind = CK_ZeroToOCLEvent;
2539  return;
2540  }
2541  Self.Diag(OpRange.getBegin(),
2542  diag::err_opencl_cast_non_zero_to_event_t)
2543  << CastInt.toString(10) << SrcExpr.get()->getSourceRange();
2544  SrcExpr = ExprError();
2545  return;
2546  }
2547  }
2548 
2549  // Reject any other conversions to non-scalar types.
2550  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cond_expect_scalar)
2551  << DestType << SrcExpr.get()->getSourceRange();
2552  SrcExpr = ExprError();
2553  return;
2554  }
2555 
2556  // The type we're casting to is known to be a scalar or vector.
2557 
2558  // Require the operand to be a scalar or vector.
2559  if (!SrcType->isScalarType() && !SrcType->isVectorType()) {
2560  Self.Diag(SrcExpr.get()->getExprLoc(),
2561  diag::err_typecheck_expect_scalar_operand)
2562  << SrcType << SrcExpr.get()->getSourceRange();
2563  SrcExpr = ExprError();
2564  return;
2565  }
2566 
2567  if (DestType->isExtVectorType()) {
2568  SrcExpr = Self.CheckExtVectorCast(OpRange, DestType, SrcExpr.get(), Kind);
2569  return;
2570  }
2571 
2572  if (const VectorType *DestVecTy = DestType->getAs<VectorType>()) {
2573  if (DestVecTy->getVectorKind() == VectorType::AltiVecVector &&
2574  (SrcType->isIntegerType() || SrcType->isFloatingType())) {
2575  Kind = CK_VectorSplat;
2576  SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2577  } else if (Self.CheckVectorCast(OpRange, DestType, SrcType, Kind)) {
2578  SrcExpr = ExprError();
2579  }
2580  return;
2581  }
2582 
2583  if (SrcType->isVectorType()) {
2584  if (Self.CheckVectorCast(OpRange, SrcType, DestType, Kind))
2585  SrcExpr = ExprError();
2586  return;
2587  }
2588 
2589  // The source and target types are both scalars, i.e.
2590  // - arithmetic types (fundamental, enum, and complex)
2591  // - all kinds of pointers
2592  // Note that member pointers were filtered out with C++, above.
2593 
2594  if (isa<ObjCSelectorExpr>(SrcExpr.get())) {
2595  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_selector_expr);
2596  SrcExpr = ExprError();
2597  return;
2598  }
2599 
2600  // If either type is a pointer, the other type has to be either an
2601  // integer or a pointer.
2602  if (!DestType->isArithmeticType()) {
2603  if (!SrcType->isIntegralType(Self.Context) && SrcType->isArithmeticType()) {
2604  Self.Diag(SrcExpr.get()->getExprLoc(),
2605  diag::err_cast_pointer_from_non_pointer_int)
2606  << SrcType << SrcExpr.get()->getSourceRange();
2607  SrcExpr = ExprError();
2608  return;
2609  }
2610  checkIntToPointerCast(/* CStyle */ true, OpRange.getBegin(), SrcExpr.get(),
2611  DestType, Self);
2612  } else if (!SrcType->isArithmeticType()) {
2613  if (!DestType->isIntegralType(Self.Context) &&
2614  DestType->isArithmeticType()) {
2615  Self.Diag(SrcExpr.get()->getLocStart(),
2616  diag::err_cast_pointer_to_non_pointer_int)
2617  << DestType << SrcExpr.get()->getSourceRange();
2618  SrcExpr = ExprError();
2619  return;
2620  }
2621  }
2622 
2623  if (Self.getLangOpts().OpenCL &&
2624  !Self.getOpenCLOptions().isEnabled("cl_khr_fp16")) {
2625  if (DestType->isHalfType()) {
2626  Self.Diag(SrcExpr.get()->getLocStart(), diag::err_opencl_cast_to_half)
2627  << DestType << SrcExpr.get()->getSourceRange();
2628  SrcExpr = ExprError();
2629  return;
2630  }
2631  }
2632 
2633  // ARC imposes extra restrictions on casts.
2635  checkObjCConversion(Sema::CCK_CStyleCast);
2636  if (SrcExpr.isInvalid())
2637  return;
2638 
2639  const PointerType *CastPtr = DestType->getAs<PointerType>();
2640  if (Self.getLangOpts().ObjCAutoRefCount && CastPtr) {
2641  if (const PointerType *ExprPtr = SrcType->getAs<PointerType>()) {
2642  Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers();
2643  Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers();
2644  if (CastPtr->getPointeeType()->isObjCLifetimeType() &&
2645  ExprPtr->getPointeeType()->isObjCLifetimeType() &&
2646  !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) {
2647  Self.Diag(SrcExpr.get()->getLocStart(),
2648  diag::err_typecheck_incompatible_ownership)
2649  << SrcType << DestType << Sema::AA_Casting
2650  << SrcExpr.get()->getSourceRange();
2651  return;
2652  }
2653  }
2654  }
2655  else if (!Self.CheckObjCARCUnavailableWeakConversion(DestType, SrcType)) {
2656  Self.Diag(SrcExpr.get()->getLocStart(),
2657  diag::err_arc_convesion_of_weak_unavailable)
2658  << 1 << SrcType << DestType << SrcExpr.get()->getSourceRange();
2659  SrcExpr = ExprError();
2660  return;
2661  }
2662  }
2663 
2664  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2665  DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
2666  DiagnoseBadFunctionCast(Self, SrcExpr, DestType);
2667  Kind = Self.PrepareScalarCast(SrcExpr, DestType);
2668  if (SrcExpr.isInvalid())
2669  return;
2670 
2671  if (Kind == CK_BitCast)
2672  checkCastAlign();
2673 }
2674 
2675 /// DiagnoseCastQual - Warn whenever casts discards a qualifiers, be it either
2676 /// const, volatile or both.
2677 static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
2678  QualType DestType) {
2679  if (SrcExpr.isInvalid())
2680  return;
2681 
2682  QualType SrcType = SrcExpr.get()->getType();
2683  if (!((SrcType->isAnyPointerType() && DestType->isAnyPointerType()) ||
2684  DestType->isLValueReferenceType()))
2685  return;
2686 
2687  QualType TheOffendingSrcType, TheOffendingDestType;
2688  Qualifiers CastAwayQualifiers;
2689  if (CastsAwayConstness(Self, SrcType, DestType, true, false,
2690  &TheOffendingSrcType, &TheOffendingDestType,
2691  &CastAwayQualifiers) !=
2692  CastAwayConstnessKind::CACK_Similar)
2693  return;
2694 
2695  // FIXME: 'restrict' is not properly handled here.
2696  int qualifiers = -1;
2697  if (CastAwayQualifiers.hasConst() && CastAwayQualifiers.hasVolatile()) {
2698  qualifiers = 0;
2699  } else if (CastAwayQualifiers.hasConst()) {
2700  qualifiers = 1;
2701  } else if (CastAwayQualifiers.hasVolatile()) {
2702  qualifiers = 2;
2703  }
2704  // This is a variant of int **x; const int **y = (const int **)x;
2705  if (qualifiers == -1)
2706  Self.Diag(SrcExpr.get()->getLocStart(), diag::warn_cast_qual2)
2707  << SrcType << DestType;
2708  else
2709  Self.Diag(SrcExpr.get()->getLocStart(), diag::warn_cast_qual)
2710  << TheOffendingSrcType << TheOffendingDestType << qualifiers;
2711 }
2712 
2714  TypeSourceInfo *CastTypeInfo,
2715  SourceLocation RPLoc,
2716  Expr *CastExpr) {
2717  CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
2718  Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2719  Op.OpRange = SourceRange(LPLoc, CastExpr->getLocEnd());
2720 
2721  if (getLangOpts().CPlusPlus) {
2722  Op.CheckCXXCStyleCast(/*FunctionalStyle=*/ false,
2723  isa<InitListExpr>(CastExpr));
2724  } else {
2725  Op.CheckCStyleCast();
2726  }
2727 
2728  if (Op.SrcExpr.isInvalid())
2729  return ExprError();
2730 
2731  // -Wcast-qual
2732  DiagnoseCastQual(Op.Self, Op.SrcExpr, Op.DestType);
2733 
2734  return Op.complete(CStyleCastExpr::Create(Context, Op.ResultType,
2735  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
2736  &Op.BasePath, CastTypeInfo, LPLoc, RPLoc));
2737 }
2738 
2740  QualType Type,
2741  SourceLocation LPLoc,
2742  Expr *CastExpr,
2743  SourceLocation RPLoc) {
2744  assert(LPLoc.isValid() && "List-initialization shouldn't get here.");
2745  CastOperation Op(*this, Type, CastExpr);
2746  Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2747  Op.OpRange = SourceRange(Op.DestRange.getBegin(), CastExpr->getLocEnd());
2748 
2749  Op.CheckCXXCStyleCast(/*FunctionalStyle=*/true, /*ListInit=*/false);
2750  if (Op.SrcExpr.isInvalid())
2751  return ExprError();
2752 
2753  auto *SubExpr = Op.SrcExpr.get();
2754  if (auto *BindExpr = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
2755  SubExpr = BindExpr->getSubExpr();
2756  if (auto *ConstructExpr = dyn_cast<CXXConstructExpr>(SubExpr))
2757  ConstructExpr->setParenOrBraceRange(SourceRange(LPLoc, RPLoc));
2758 
2759  return Op.complete(CXXFunctionalCastExpr::Create(Context, Op.ResultType,
2760  Op.ValueKind, CastTypeInfo, Op.Kind,
2761  Op.SrcExpr.get(), &Op.BasePath, LPLoc, RPLoc));
2762 }
Defines the clang::ASTContext interface.
bool RequireNonAbstractType(SourceLocation Loc, QualType T, TypeDiagnoser &Diagnoser)
Represents a function declaration or definition.
Definition: Decl.h:1716
static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType)
Definition: SemaCast.cpp:1967
static DiagnosticBuilder Diag(DiagnosticsEngine *Diags, const LangOptions &Features, FullSourceLoc TokLoc, const char *TokBegin, const char *TokRangeBegin, const char *TokRangeEnd, unsigned DiagID)
Produce a diagnostic highlighting some portion of a literal.
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2393
QualType getPointeeType() const
Definition: Type.h:2406
A (possibly-)qualified type.
Definition: Type.h:655
bool isBlockPointerType() const
Definition: Type.h:6121
bool isMemberPointerType() const
Definition: Type.h:6144
IdentifierInfo * getIdentifierInfo(StringRef Name) const
Return information about the specified preprocessor identifier token.
A cast other than a C-style cast.
Definition: Sema.h:9305
SourceRange getSourceRange() const LLVM_READONLY
Retrieve the source range covering the entirety of this nested-name-specifier.
const ASTRecordLayout & getASTRecordLayout(const RecordDecl *D) const
Get or compute information about the layout of the specified record (struct/union/class) D...
bool isArithmeticType() const
Definition: Type.cpp:1956
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3211
ARCConversionResult CheckObjCConversion(SourceRange castRange, QualType castType, Expr *&op, CheckedConversionKind CCK, bool Diagnose=true, bool DiagnoseCFAudited=false, BinaryOperatorKind Opc=BO_PtrMemD)
Checks for invalid conversions and casts between retainable pointers and other pointer kinds for ARC ...
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:497
CharUnits getBaseClassOffset(const CXXRecordDecl *Base) const
getBaseClassOffset - Get the offset, in chars, for the given base class.
Definition: RecordLayout.h:233
static CXXDynamicCastExpr * Create(const ASTContext &Context, QualType T, ExprValueKind VK, CastKind Kind, Expr *Op, const CXXCastPath *Path, TypeSourceInfo *Written, SourceLocation L, SourceLocation RParenLoc, SourceRange AngleBrackets)
Definition: ExprCXX.cpp:582
bool isRealFloatingType() const
Floating point categories.
Definition: Type.cpp:1941
bool isRecordType() const
Definition: Type.h:6186
SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID)
Emit a diagnostic.
Definition: Sema.h:1281
static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, Sema::CheckedConversionKind CCK, SourceRange OpRange, unsigned &msg, CastKind &Kind, CXXCastPath &BasePath, bool ListInitialization)
TryStaticCast - Check if a static cast can be performed, and do so if possible.
Definition: SemaCast.cpp:1050
bool isExtVectorType() const
Definition: Type.h:6202
The cast method is appropriate and successful.
Definition: SemaCast.cpp:35
FailureKind getFailureKind() const
Determine why initialization failed.
CanQualType ARCUnbridgedCastTy
Definition: ASTContext.h:1035
The base class of the type hierarchy.
Definition: Type.h:1428
bool isDerivedFrom(const CXXRecordDecl *Base) const
Determine whether this class is derived from the class Base.
StringRef getLastMacroWithSpelling(SourceLocation Loc, ArrayRef< TokenValue > Tokens) const
Return the name of the macro defined before Loc that has spelling Tokens.
static ExprValueKind getValueKindForType(QualType T)
getValueKindForType - Given a formal return or parameter type, give its value kind.
Definition: Expr.h:395
Overloading for a user-defined conversion failed.
bool isZero() const
isZero - Test whether the quantity equals zero.
Definition: CharUnits.h:116
Ambiguous candidates found.
Definition: Overload.h:60
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:679
A container of type source information.
Definition: Decl.h:86
static CXXFunctionalCastExpr * Create(const ASTContext &Context, QualType T, ExprValueKind VK, TypeSourceInfo *Written, CastKind Kind, Expr *Op, const CXXCastPath *Path, SourceLocation LPLoc, SourceLocation RPLoc)
Definition: ExprCXX.cpp:686
Represents a path from a specific derived class (which is not represented as part of the path) to a p...
static_cast
Definition: SemaCast.cpp:48
static InitializedEntity InitializeTemporary(QualType Type)
Create the initialization entity for a temporary.
bool isCompleteDefinition() const
Return true if this decl has its body fully specified.
Definition: Decl.h:3171
bool isUnsignedIntegerType() const
Return true if this is an integer type that is unsigned, according to C99 6.2.5p6 [which returns true...
Definition: Type.cpp:1888
bool CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, CastKind &Kind)
Definition: SemaExpr.cpp:6062
An Objective-C array/dictionary subscripting which reads an object or writes at the subscripted array...
Definition: Specifiers.h:141
Information about one declarator, including the parsed type information and the identifier.
Definition: DeclSpec.h:1752
void removeObjCLifetime()
Definition: Type.h:349
DiagnosticsEngine & Diags
Definition: Sema.h:321
bool isEnumeralType() const
Definition: Type.h:6190
static void DiagnoseCallingConvCast(Sema &Self, const ExprResult &SrcExpr, QualType DstType, SourceRange OpRange)
Diagnose casts that change the calling convention of a pointer to a function defined in the current T...
Definition: SemaCast.cpp:1826
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6526
void clear()
Clear the base-paths results.
CastAwayConstnessKind
The kind of unwrapping we did when determining whether a conversion casts away constness.
Definition: SemaCast.cpp:452
QualType getMemberPointerType(QualType T, const Type *Cls) const
Return the uniqued reference to the type for a member pointer to the specified type in the specified ...
DeclarationName getName() const
Gets the name looked up.
Definition: ExprCXX.h:2743
bool isInvalidDecl() const
Definition: DeclBase.h:549
OpenCLOptions & getOpenCLOptions()
Definition: Sema.h:1205
Defines the clang::Expr interface and subclasses for C++ expressions.
The collection of all-type qualifiers we support.
Definition: Type.h:154
bool isRecordingPaths() const
Whether we are recording paths.
bool UnwrapSimilarTypes(QualType &T1, QualType &T2)
Attempt to unwrap two types that may be similar (C++ [conv.qual]).
Expr * FixOverloadedFunctionReference(Expr *E, DeclAccessPair FoundDecl, FunctionDecl *Fn)
FixOverloadedFunctionReference - E is an expression that refers to a C++ overloaded function (possibl...
Represents a struct/union/class.
Definition: Decl.h:3570
One of these records is kept for each identifier that is lexed.
TargetCXXABI getCXXABI() const
Get the C++ ABI currently in use.
Definition: TargetInfo.h:1010
void setRecordingPaths(bool RP)
Specify whether we should be recording paths or not.
A vector component is an element or range of elements on a vector.
Definition: Specifiers.h:132
(Type)expr
Definition: SemaCast.cpp:51
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:150
bool allowsNonTrivialObjCLifetimeQualifiers() const
True if any ObjC types may have non-trivial lifetime qualifiers.
Definition: LangOptions.h:250
bool isObjCLifetimeType() const
Returns true if objects of this type have lifetime semantics under ARC.
Definition: Type.cpp:3958
The cast method is not applicable.
Definition: SemaCast.cpp:34
A C-style cast.
Definition: Sema.h:9301
RecordDecl * getDefinition() const
Returns the RecordDecl that actually defines this struct/union/class.
Definition: Decl.h:3776
bool IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base)
Determine whether the type Derived is a C++ class that is derived from the type Base.
TryCastResult
Definition: SemaCast.cpp:33
static TryCastResult getCastAwayConstnessCastKind(CastAwayConstnessKind CACK, unsigned &DiagID)
Definition: SemaCast.cpp:652
void removeConst()
Definition: Type.h:275
bool isReferenceType() const
Definition: Type.h:6125
static CharUnits Zero()
Zero - Construct a CharUnits quantity of zero.
Definition: CharUnits.h:53
Ref_Incompatible - The two types are incompatible, so direct reference binding is not possible...
Definition: Sema.h:9677
Expr * getSubExpr()
Definition: Expr.h:2892
bool isAtLeastAsQualifiedAs(QualType Other) const
Determine whether this type is at least as qualified as the other given type, requiring exact equalit...
Definition: Type.h:6043
bool isIntegralOrEnumerationType() const
Determine whether this type is an integral or enumeration type.
Definition: Type.h:6440
OverloadCandidateDisplayKind
Definition: Overload.h:66
An r-value expression (a pr-value in the C++11 taxonomy) produces a temporary value.
Definition: Specifiers.h:110
bool isInvalidType() const
Definition: DeclSpec.h:2432
bool isGLValue() const
Definition: Expr.h:252
static bool isValidCast(TryCastResult TCR)
Definition: SemaCast.cpp:42
bool isCompleteType(SourceLocation Loc, QualType T)
Definition: Sema.h:1616
An rvalue reference type, per C++11 [dcl.ref].
Definition: Type.h:2594
PtrTy get() const
Definition: Ownership.h:174
tok::TokenKind getTokenID() const
If this is a source-language token (e.g.
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:38
ReferenceCompareResult CompareReferenceRelationship(SourceLocation Loc, QualType T1, QualType T2, bool &DerivedToBase, bool &ObjCConversion, bool &ObjCLifetimeConversion)
CompareReferenceRelationship - Compare the two types T1 and T2 to determine whether they are referenc...
Succeeded, but refers to a deleted function.
Definition: Overload.h:63
uint32_t Offset
Definition: CacheTokens.cpp:43
Ref_Compatible - The two types are reference-compatible.
Definition: Sema.h:9683
OverloadCandidateSet & getFailedCandidateSet()
Retrieve a reference to the candidate set when overload resolution fails.
ExprValueKind getValueKind() const
getValueKind - The value kind that this expression produces.
Definition: Expr.h:405
const Type * getClass() const
Definition: Type.h:2646
bool isRValueReferenceType() const
Definition: Type.h:6133
CheckedConversionKind
The kind of conversion being performed.
Definition: Sema.h:9297
static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, bool CStyle, SourceRange OpRange, unsigned &msg, CastKind &Kind)
Definition: SemaCast.cpp:1973
FunctionDecl * ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, QualType TargetType, bool Complain, DeclAccessPair &Found, bool *pHadMultipleCandidates=nullptr)
ResolveAddressOfOverloadedFunction - Try to resolve the address of an overloaded function (C++ [over...
ExprResult Perform(Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind, MultiExprArg Args, QualType *ResultType=nullptr)
Perform the actual initialization of the given entity based on the computed initialization sequence...
Definition: SemaInit.cpp:7154
const RecordType * getDetectedVirtual() const
The virtual base discovered on the path (if we are merely detecting virtuals).
const Type * getTypePtr() const
Retrieves a pointer to the underlying (unqualified) type.
Definition: Type.h:5889
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:2827
static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr, QualType DestType)
DiagnoseCastQual - Warn whenever casts discards a qualifiers, be it either const, volatile or both...
Definition: SemaCast.cpp:2677
const internal::VariadicDynCastAllOfMatcher< Stmt, CastExpr > castExpr
Matches any cast nodes of Clang&#39;s AST.
const LangOptions & getLangOpts() const
Definition: Sema.h:1204
ExprResult DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose=true)
Definition: SemaExpr.cpp:628
bool isScalarType() const
Definition: Type.h:6425
bool compatiblyIncludesObjCLifetime(Qualifiers other) const
Determines if these qualifiers compatibly include another set of qualifiers from the narrow perspecti...
Definition: Type.h:520
An ordinary object is located at an address in memory.
Definition: Specifiers.h:126
CastKind PrepareScalarCast(ExprResult &src, QualType destType)
Prepares for a scalar cast, performing all the necessary stages except the final cast and returning t...
Definition: SemaExpr.cpp:5835
static CastAwayConstnessKind unwrapCastAwayConstnessLevel(ASTContext &Context, QualType &T1, QualType &T2)
Unwrap one level of types for CastsAwayConstness.
Definition: SemaCast.cpp:479
bool hasConst() const
Definition: Type.h:271
bool isHalfType() const
Definition: Type.h:6346
Sema - This implements semantic analysis and AST building for C.
Definition: Sema.h:277
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1627
A functional-style cast.
Definition: Sema.h:9303
bool compatiblyIncludes(Qualifiers other) const
Determines if these qualifiers compatibly include another set.
Definition: Type.h:499
bool isComplexType() const
isComplexType() does not include complex integers (a GCC extension).
Definition: Type.cpp:473
CastKind
CastKind - The kind of operation required for a conversion.
static ImplicitCastExpr * Create(const ASTContext &Context, QualType T, CastKind Kind, Expr *Operand, const CXXCastPath *BasePath, ExprValueKind Cat)
Definition: Expr.cpp:1785
bool UnwrapSimilarArrayTypes(QualType &T1, QualType &T2)
Attempt to unwrap two types that may both be array types with the same bound (or both be array types ...
static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, bool CStyle, unsigned &msg)
TryConstCast - See if a const_cast from source to destination is allowed, and perform it if it is...
Definition: SemaCast.cpp:1654
bool isEnabled(llvm::StringRef Ext) const
Definition: OpenCLOptions.h:39
ASTRecordLayout - This class contains layout information for one RecordDecl, which is a struct/union/...
Definition: RecordLayout.h:39
An Objective-C property is a logical field of an Objective-C object which is read and written via Obj...
Definition: Specifiers.h:136
bool isEventT() const
Definition: Type.h:6271
Expr - This represents one expression.
Definition: Expr.h:106
static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType, SourceRange opRange, Expr *src, QualType destType, bool listInitialization)
Diagnose a failed cast.
Definition: SemaCast.cpp:410
QualType getPointeeType() const
Definition: Type.h:2550
ExprValueKind
The categorization of expression values, currently following the C++11 scheme.
Definition: Specifiers.h:107
static InitializationKind CreateFunctionalCast(SourceRange TypeRange, bool InitList)
Create a direct initialization for a functional cast.
void BuildBasePathArray(const CXXBasePaths &Paths, CXXCastPath &BasePath)
static FindResult find(Expr *E)
Finds the overloaded expression in the given expression E of OverloadTy.
Definition: ExprCXX.h:2700
const CXXRecordDecl * getPointeeCXXRecordDecl() const
If this is a pointer or reference to a RecordType, return the CXXRecordDecl that the type refers to...
Definition: Type.cpp:1612
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6589
OverloadingResult getFailedOverloadResult() const
Get the overloading result, for when the initialization sequence failed due to a bad overload...
The cast method is appropriate and accepted as a language extension.
Definition: SemaCast.cpp:36
Defines the clang::Preprocessor interface.
bool isNullPtrType() const
Definition: Type.h:6365
static CXXStaticCastExpr * Create(const ASTContext &Context, QualType T, ExprValueKind VK, CastKind K, Expr *Op, const CXXCastPath *Path, TypeSourceInfo *Written, SourceLocation L, SourceLocation RParenLoc, SourceRange AngleBrackets)
Definition: ExprCXX.cpp:553
CXXRecordDecl * getDefinition() const
Definition: DeclCXX.h:771
Overload resolution succeeded.
Definition: Overload.h:54
ExprResult BuildCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind, TypeSourceInfo *Ty, Expr *E, SourceRange AngleBrackets, SourceRange Parens)
Definition: SemaCast.cpp:255
Stores token information for comparing actual tokens with predefined values.
Definition: Preprocessor.h:88
ExprResult CheckPlaceholderExpr(Expr *E)
Check for operands with placeholder types and complain if found.
Definition: SemaExpr.cpp:16367
static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, Sema::CheckedConversionKind CCK, SourceRange OpRange, unsigned &msg, CastKind &Kind, bool ListInitialization)
TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2 is valid: ...
Definition: SemaCast.cpp:1599
bool isConstructorInitialization() const
Determine whether this initialization is direct call to a constructor.
Definition: SemaInit.cpp:3246
ReferenceCompareResult
ReferenceCompareResult - Expresses the result of comparing two types (cv1 T1 and cv2 T2) to determine...
Definition: Sema.h:9674
bool RequireCompleteType(SourceLocation Loc, QualType T, TypeDiagnoser &Diagnoser)
Ensure that the type T is a complete type.
Definition: SemaType.cpp:7497
bool isSignedIntegerType() const
Return true if this is an integer type that is signed, according to C99 6.2.5p4 [char, signed char, short, int, long..], or an enum decl which has a signed representation.
Definition: Type.cpp:1848
QualType getType() const
Definition: Expr.h:128
static TryCastResult TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr, QualType SrcType, QualType DestType, bool CStyle, SourceRange OpRange, unsigned &msg, CastKind &Kind, CXXCastPath &BasePath)
TryStaticMemberPointerUpcast - Tests whether a conversion according to C++ 5.2.9p9 is valid: ...
Definition: SemaCast.cpp:1481
bool ResolveAndFixSingleFunctionTemplateSpecialization(ExprResult &SrcExpr, bool DoFunctionPointerConverion=false, bool Complain=false, SourceRange OpRangeForComplaining=SourceRange(), QualType DestTypeForComplaining=QualType(), unsigned DiagIDForComplaining=0)
bool resolveAndFixAddressOfOnlyViableOverloadCandidate(ExprResult &SrcExpr, bool DoFunctionPointerConversion=false)
Given an overloaded function, tries to turn it into a non-overloaded function reference using resolve...
Type(expr)
Definition: SemaCast.cpp:52
bool isAtLeastAsQualifiedAs(CanQual< T > Other) const
Determines whether this canonical type is at least as qualified as the Other canonical type...
bool isInvalid() const
Definition: Ownership.h:170
SourceLocation getEnd() const
Preprocessor & getPreprocessor() const
Definition: Sema.h:1210
Represents a GCC generic vector type.
Definition: Type.h:3024
static TryCastResult TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType, bool CStyle, SourceRange OpRange, unsigned &msg, CastKind &Kind, CXXCastPath &BasePath)
Tests whether a conversion according to C++ 5.2.9p5 is valid.
Definition: SemaCast.cpp:1297
bool isUsable() const
Definition: Ownership.h:171
bool CheckTollFreeBridgeStaticCast(QualType castType, Expr *castExpr, CastKind &Kind)
QualType getTypeDeclType(const TypeDecl *Decl, const TypeDecl *PrevDecl=nullptr) const
Return the unique reference to the type for the specified type declaration.
Definition: ASTContext.h:1381
The result type of a method or function.
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:236
bool isKeyword(const LangOptions &LangOpts) const
Return true if this token is a keyword in the specified language.
unsigned getCVRQualifiers() const
Retrieve the set of CVR (const-volatile-restrict) qualifiers applied to this type.
Definition: Type.h:5922
ExprResult BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, SourceLocation RParenLoc, Expr *Op)
Definition: SemaCast.cpp:2713
bool isVoidPointerType() const
Definition: Type.cpp:461
bool areLaxCompatibleVectorTypes(QualType srcType, QualType destType)
Are the two types lax-compatible vector types? That is, given that one of them is a vector...
Definition: SemaExpr.cpp:6027
RecordDecl * getDecl() const
Definition: Type.h:4145
static TryCastResult TryStaticDowncast(Sema &Self, CanQualType SrcType, CanQualType DestType, bool CStyle, SourceRange OpRange, QualType OrigSrcType, QualType OrigDestType, unsigned &msg, CastKind &Kind, CXXCastPath &BasePath)
TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and TryStaticPointerDowncast.
Definition: SemaCast.cpp:1369
CanQualType OverloadTy
Definition: ASTContext.h:1033
static CXXConstCastExpr * Create(const ASTContext &Context, QualType T, ExprValueKind VK, Expr *Op, TypeSourceInfo *WrittenTy, SourceLocation L, SourceLocation RParenLoc, SourceRange AngleBrackets)
Definition: ExprCXX.cpp:672
Kind
A reference to an overloaded function set, either an UnresolvedLookupExpr or an UnresolvedMemberExpr...
Definition: ExprCXX.h:2636
ActionResult - This structure is used while parsing/acting on expressions, stmts, etc...
Definition: Ownership.h:157
ASTContext & getASTContext() const
Definition: Sema.h:1211
Encodes a location in the source.
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of enums...
Definition: Type.h:4161
CastKind PrepareCastToObjCObjectPointer(ExprResult &E)
Prepare a conversion of the given expression to an ObjC object pointer type.
Definition: SemaExpr.cpp:5820
static TryCastResult TryStaticPointerDowncast(Sema &Self, QualType SrcType, QualType DestType, bool CStyle, SourceRange OpRange, unsigned &msg, CastKind &Kind, CXXCastPath &BasePath)
Tests whether a conversion according to C++ 5.2.9p8 is valid.
Definition: SemaCast.cpp:1335
static const FieldDecl * getTargetFieldForToUnionCast(QualType unionType, QualType opType)
Definition: Expr.cpp:1765
SourceLocation getLocStart() const LLVM_READONLY
Definition: Stmt.h:401
bool isIntegralType(const ASTContext &Ctx) const
Determine whether this type is an integral type.
Definition: Type.cpp:1763
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2045
paths_iterator begin()
ExprResult ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind, SourceLocation LAngleBracketLoc, Declarator &D, SourceLocation RAngleBracketLoc, SourceLocation LParenLoc, Expr *E, SourceLocation RParenLoc)
ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast&#39;s.
Definition: SemaCast.cpp:232
bool CheckObjCARCUnavailableWeakConversion(QualType castType, QualType ExprType)
std::string getAmbiguousPathsDisplayString(CXXBasePaths &Paths)
Builds a string representing ambiguous paths from a specific derived class to different subobjects of...
const ArrayType * getAsArrayType(QualType T) const
Type Query functions.
Represents a canonical, potentially-qualified type.
Definition: CanonicalType.h:66
TokenKind
Provides a simple uniform namespace for tokens from all C languages.
Definition: TokenKinds.h:25
Describes the kind of initialization being performed, along with location information for tokens rela...
const_cast
Definition: SemaCast.cpp:47
bool isMemberFunctionPointerType() const
Definition: Type.h:6148
bool isObjCObjectPointerType() const
Definition: Type.h:6210
bool isAnyPointerType() const
Definition: Type.h:6117
ImplicitCastExpr - Allows us to explicitly represent implicit type conversions, which have no direct ...
Definition: Expr.h:2961
bool isLValue() const
isLValue - True if this expression is an "l-value" according to the rules of the current language...
Definition: Expr.h:249
Overloading for initialization by constructor failed.
is AltiVec vector
Definition: Type.h:3031
Requests that all candidates be shown.
Definition: Overload.h:69
SourceLocation getLocEnd() const LLVM_READONLY
Definition: Stmt.h:403
bool isAddressSpaceOverlapping(const PointerType &other) const
Returns true if address spaces of pointers overlap.
Definition: Type.h:2416
bool isAnyCharacterType() const
Determine whether this type is any of the built-in character types.
Definition: Type.cpp:1827
bool isVectorType() const
Definition: Type.h:6198
void removeObjCGCAttr()
Definition: Type.h:326
OverloadCandidateSet - A set of overload candidates, used in C++ overload resolution (C++ 13...
Definition: Overload.h:830
reinterpret_cast
Definition: SemaCast.cpp:49
static InitializationKind CreateCast(SourceRange TypeRange)
Create a direct initialization due to a cast that isn&#39;t a C-style or functional cast.
bool hasSameUnqualifiedType(QualType T1, QualType T2) const
Determine whether the given types are equivalent after cvr-qualifiers have been removed.
Definition: ASTContext.h:2275
static CXXReinterpretCastExpr * Create(const ASTContext &Context, QualType T, ExprValueKind VK, CastKind Kind, Expr *Op, const CXXCastPath *Path, TypeSourceInfo *WrittenTy, SourceLocation L, SourceLocation RParenLoc, SourceRange AngleBrackets)
Definition: ExprCXX.cpp:645
CanProxy< U > getAs() const
Retrieve a canonical type pointer with a different static type, upcasting or downcasting as needed...
ExprResult checkUnknownAnyCast(SourceRange TypeRange, QualType CastType, Expr *CastExpr, CastKind &CastKind, ExprValueKind &VK, CXXCastPath &Path)
Check a cast of an unknown-any type.
Definition: SemaExpr.cpp:16275
A POD class for pairing a NamedDecl* with an access specifier.
bool isPlaceholderType() const
Test for a type which does not represent an actual type-system type but is instead used as a placehol...
Definition: Type.h:6314
dynamic_cast
Definition: SemaCast.cpp:50
Represents an element in a path from a derived class to a base class.
CallingConv getDefaultCallingConvention(bool IsVariadic, bool IsCXXMethod) const
Retrieves the default calling convention for the current target.
std::list< CXXBasePath >::const_iterator const_paths_iterator
Dataflow Directional Tag Classes.
bool isValid() const
Return true if this is a valid SourceLocation object.
void CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType, bool IsDereference, SourceRange Range)
Definition: SemaCast.cpp:1757
bool hasCvrSimilarType(QualType T1, QualType T2)
Determine if two types are similar, ignoring only CVR qualifiers.
The cast method is appropriate, but failed.
Definition: SemaCast.cpp:38
static std::string getAsString(SplitQualType split, const PrintingPolicy &Policy)
Definition: Type.h:988
const CXXRecordDecl * getParent() const
Returns the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2165
bool isBooleanType() const
Definition: Type.h:6453
ExprResult prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr)
Prepare SplattedExpr for a vector splat operation, adding implicit casts if necessary.
Definition: SemaExpr.cpp:6082
static void checkIntToPointerCast(bool CStyle, SourceLocation Loc, const Expr *SrcExpr, QualType DestType, Sema &Self)
Definition: SemaCast.cpp:1914
Requests that only viable candidates be shown.
Definition: Overload.h:72
bool isAmbiguous(CanQualType BaseType)
Determine whether the path from the most-derived type to the given base type is ambiguous (i...
A pointer to member type per C++ 8.3.3 - Pointers to members.
Definition: Type.h:2612
bool isIntegerConstantExpr(llvm::APSInt &Result, const ASTContext &Ctx, SourceLocation *Loc=nullptr, bool isEvaluated=true) const
isIntegerConstantExpr - Return true if this expression is a valid integer constant expression...
static InitializationKind CreateCStyleCast(SourceLocation StartLoc, SourceRange TypeRange, bool InitList)
Create a direct initialization for a C-style cast.
void CheckCastAlign(Expr *Op, QualType T, SourceRange TRange)
CheckCastAlign - Implements -Wcast-align, which warns when a pointer cast increases the alignment req...
static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr, QualType DestType)
Definition: SemaCast.cpp:1807
static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType, ExprResult &Result)
Definition: SemaCast.cpp:1940
Expr * IgnoreParenImpCasts() LLVM_READONLY
IgnoreParenImpCasts - Ignore parentheses and implicit casts.
Definition: Expr.cpp:2631
ExprResult IgnoredValueConversions(Expr *E)
IgnoredValueConversions - Given that an expression&#39;s result is syntactically ignored, perform any conversions that are required.
SourceRange getSourceRange() const LLVM_READONLY
Get the full source range.
Definition: TypeLoc.h:150
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of structs/unions/cl...
Definition: Type.h:4135
static bool tryDiagnoseOverloadedCast(Sema &S, CastType CT, SourceRange range, Expr *src, QualType destType, bool listInitialization)
Try to diagnose a failed overloaded cast.
Definition: SemaCast.cpp:334
bool isIntegerType() const
isIntegerType() does not include complex integers (a GCC extension).
Definition: Type.h:6374
ExprResult CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *CastExpr, CastKind &Kind)
Definition: SemaExpr.cpp:6115
static CStyleCastExpr * Create(const ASTContext &Context, QualType T, ExprValueKind VK, CastKind K, Expr *Op, const CXXCastPath *BasePath, TypeSourceInfo *WrittenTy, SourceLocation L, SourceLocation R)
Definition: Expr.cpp:1810
bool CheckDerivedToBaseConversion(QualType Derived, QualType Base, SourceLocation Loc, SourceRange Range, CXXCastPath *BasePath=nullptr, bool IgnoreAccess=false)
bool isFunctionType() const
Definition: Type.h:6109
MaterializeTemporaryExpr * CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary, bool BoundToLvalueReference)
Definition: SemaInit.cpp:7120
CXXBasePath & front()
Base for LValueReferenceType and RValueReferenceType.
Definition: Type.h:2529
bool hasSameType(QualType T1, QualType T2) const
Determine whether the given types T1 and T2 are equivalent.
Definition: ASTContext.h:2251
static TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr, QualType DestType, bool CStyle, CastKind &Kind, CXXCastPath &BasePath, unsigned &msg)
Tests whether a conversion according to N2844 is valid.
Definition: SemaCast.cpp:1239
static FixItHint CreateInsertion(SourceLocation InsertionLoc, StringRef Code, bool BeforePreviousInsertions=false)
Create a code modification hint that inserts the given code string at a specific location.
Definition: Diagnostic.h:92
Implements a partial diagnostic that can be emitted anwyhere in a DiagnosticBuilder stream...
QualType getNonLValueExprType(const ASTContext &Context) const
Determine the type of a (typically non-lvalue) expression with the specified result type...
Definition: Type.cpp:2804
A bitfield object is a bitfield on a C or C++ record.
Definition: Specifiers.h:129
uint64_t getTypeSize(QualType T) const
Return the size of the specified (complete) type T, in bits.
Definition: ASTContext.h:2052
bool isObjCObjectType() const
Definition: Type.h:6214
QualType withCVRQualifiers(unsigned CVR) const
Definition: Type.h:847
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
Definition: ASTContext.h:2235
bool isLValueReferenceType() const
Definition: Type.h:6129
ExprResult BuildCXXFunctionalCastExpr(TypeSourceInfo *TInfo, QualType Type, SourceLocation LParenLoc, Expr *CastExpr, SourceLocation RParenLoc)
Definition: SemaCast.cpp:2739
TypeLoc getTypeLoc() const
Return the TypeLoc wrapper for the type source info.
Definition: TypeLoc.h:239
bool Failed() const
Determine whether the initialization sequence is invalid.
CallingConv getCallConv() const
Definition: Type.h:3375
Describes the sequence of initializations required to initialize a given object or reference with a s...
QualType getUnqualifiedType() const
Retrieve the unqualified variant of the given type, removing as little sugar as possible.
Definition: Type.h:5969
Represents a C++ struct/union/class.
Definition: DeclCXX.h:302
bool isMemberFunctionPointer() const
Returns true if the member type (i.e.
Definition: Type.h:2636
bool isVoidType() const
Definition: Type.h:6340
static CastAwayConstnessKind CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType, bool CheckCVR, bool CheckObjCLifetime, QualType *TheOffendingSrcType=nullptr, QualType *TheOffendingDestType=nullptr, Qualifiers *CastAwayQualifiers=nullptr)
Check if the pointer conversion from SrcType to DestType casts away constness as defined in C++ [expr...
Definition: SemaCast.cpp:557
Qualifiers getQualifiers() const
Retrieve the set of qualifiers applied to this type.
Definition: Type.h:5916
AccessResult CheckBaseClassAccess(SourceLocation AccessLoc, QualType Base, QualType Derived, const CXXBasePath &Path, unsigned DiagID, bool ForceCheck=false, bool ForceUnprivileged=false)
Checks access for a hierarchy conversion.
QualType getPointerType(QualType T) const
Return the uniqued reference to the type for a pointer to the specified type.
static FixItHint CreateReplacement(CharSourceRange RemoveRange, StringRef Code)
Create a code modification hint that replaces the given source range with the given code string...
Definition: Diagnostic.h:129
This class is used for builtin types like &#39;int&#39;.
Definition: Type.h:2250
SourceRange getSourceRange() const LLVM_READONLY
SourceLocation tokens are not useful in isolation - they are low level value objects created/interpre...
Definition: Stmt.cpp:266
Defines the clang::TargetInfo interface.
bool isComplexIntegerType() const
Definition: Type.cpp:479
bool isMicrosoft() const
Is this ABI an MSVC-compatible ABI?
Definition: TargetCXXABI.h:154
unsigned getCVRQualifiers() const
Definition: Type.h:293
ExprResult ExprError()
Definition: Ownership.h:283
static Qualifiers fromCVRMask(unsigned CVR)
Definition: Type.h:247
bool hasVolatile() const
Definition: Type.h:278
static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr, QualType DestType)
DiagnoseBadFunctionCast - Warn whenever a function call is cast to a non-matching type...
Definition: SemaCast.cpp:2410
bool isDependentType() const
Whether this type is a dependent type, meaning that its definition somehow depends on a template para...
Definition: Type.h:1942
A reference to a declared variable, function, enum, etc.
Definition: Expr.h:974
bool isIgnored(unsigned DiagID, SourceLocation Loc) const
Determine whether the diagnostic is known to be ignored.
Definition: Diagnostic.h:818
bool isUnion() const
Definition: Decl.h:3239
NestedNameSpecifierLoc getQualifierLoc() const
Fetches the nested-name qualifier with source-location information, if one was given.
Definition: ExprCXX.h:2755
bool isPointerType() const
Definition: Type.h:6113
void NoteAllOverloadCandidates(Expr *E, QualType DestType=QualType(), bool TakingAddress=false)
BasePaths - Represents the set of paths from a derived class to one of its (direct or indirect) bases...
No viable function found.
Definition: Overload.h:57
static StringRef getNameForCallConv(CallingConv CC)
Definition: Type.cpp:2820
bool isFloatingType() const
Definition: Type.cpp:1925
A trivial tuple used to represent a source range.
ASTContext & Context
Definition: Sema.h:319
paths_iterator end()
Describes an entity that is being initialized.
bool isFunctionPointerType() const
Definition: Type.h:6137
SourceLocation getBegin() const
const LangOptions & getLangOpts() const
Definition: ASTContext.h:696
void NoteCandidates(Sema &S, OverloadCandidateDisplayKind OCD, ArrayRef< Expr *> Args, StringRef Opc="", SourceLocation Loc=SourceLocation(), llvm::function_ref< bool(OverloadCandidate &)> Filter=[](OverloadCandidate &) { return true;})
When overload resolution fails, prints diagnostic messages containing the candidates in the candidate...
QualType getUnqualifiedArrayType(QualType T, Qualifiers &Quals)
Return this type as a completely-unqualified array type, capturing the qualifiers in Quals...
bool isIncompleteOrObjectType() const
Return true if this is an incomplete or object type, in other words, not a function type...
Definition: Type.h:1741
CastType
Definition: SemaCast.cpp:46
QualType getPointeeType() const
Definition: Type.h:2632
static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr, QualType DestType, SourceRange OpRange)
Check that a reinterpret_cast<DestType>(SrcExpr) is not used as upcast or downcast between respective...
Definition: SemaCast.cpp:848
QualType getType() const
Return the type wrapped by this type source info.
Definition: Decl.h:97
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:127