clang  8.0.0svn
SemaCast.cpp
Go to the documentation of this file.
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 static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType) {
1048  auto *SrcPtrType = SrcType->getAs<PointerType>();
1049  if (!SrcPtrType)
1050  return false;
1051  auto *DestPtrType = DestType->getAs<PointerType>();
1052  if (!DestPtrType)
1053  return false;
1054  return SrcPtrType->getPointeeType().getAddressSpace() !=
1055  DestPtrType->getPointeeType().getAddressSpace();
1056 }
1057 
1058 /// TryStaticCast - Check if a static cast can be performed, and do so if
1059 /// possible. If @p CStyle, ignore access restrictions on hierarchy casting
1060 /// and casting away constness.
1062  QualType DestType,
1064  SourceRange OpRange, unsigned &msg,
1065  CastKind &Kind, CXXCastPath &BasePath,
1066  bool ListInitialization) {
1067  // Determine whether we have the semantics of a C-style cast.
1068  bool CStyle
1069  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1070 
1071  // The order the tests is not entirely arbitrary. There is one conversion
1072  // that can be handled in two different ways. Given:
1073  // struct A {};
1074  // struct B : public A {
1075  // B(); B(const A&);
1076  // };
1077  // const A &a = B();
1078  // the cast static_cast<const B&>(a) could be seen as either a static
1079  // reference downcast, or an explicit invocation of the user-defined
1080  // conversion using B's conversion constructor.
1081  // DR 427 specifies that the downcast is to be applied here.
1082 
1083  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
1084  // Done outside this function.
1085 
1086  TryCastResult tcr;
1087 
1088  // C++ 5.2.9p5, reference downcast.
1089  // See the function for details.
1090  // DR 427 specifies that this is to be applied before paragraph 2.
1091  tcr = TryStaticReferenceDowncast(Self, SrcExpr.get(), DestType, CStyle,
1092  OpRange, msg, Kind, BasePath);
1093  if (tcr != TC_NotApplicable)
1094  return tcr;
1095 
1096  // C++11 [expr.static.cast]p3:
1097  // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to cv2
1098  // T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1099  tcr = TryLValueToRValueCast(Self, SrcExpr.get(), DestType, CStyle, Kind,
1100  BasePath, msg);
1101  if (tcr != TC_NotApplicable)
1102  return tcr;
1103 
1104  // C++ 5.2.9p2: An expression e can be explicitly converted to a type T
1105  // [...] if the declaration "T t(e);" is well-formed, [...].
1106  tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg,
1107  Kind, ListInitialization);
1108  if (SrcExpr.isInvalid())
1109  return TC_Failed;
1110  if (tcr != TC_NotApplicable)
1111  return tcr;
1112 
1113  // C++ 5.2.9p6: May apply the reverse of any standard conversion, except
1114  // lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
1115  // conversions, subject to further restrictions.
1116  // Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
1117  // of qualification conversions impossible.
1118  // In the CStyle case, the earlier attempt to const_cast should have taken
1119  // care of reverse qualification conversions.
1120 
1121  QualType SrcType = Self.Context.getCanonicalType(SrcExpr.get()->getType());
1122 
1123  // C++0x 5.2.9p9: A value of a scoped enumeration type can be explicitly
1124  // converted to an integral type. [...] A value of a scoped enumeration type
1125  // can also be explicitly converted to a floating-point type [...].
1126  if (const EnumType *Enum = SrcType->getAs<EnumType>()) {
1127  if (Enum->getDecl()->isScoped()) {
1128  if (DestType->isBooleanType()) {
1129  Kind = CK_IntegralToBoolean;
1130  return TC_Success;
1131  } else if (DestType->isIntegralType(Self.Context)) {
1132  Kind = CK_IntegralCast;
1133  return TC_Success;
1134  } else if (DestType->isRealFloatingType()) {
1135  Kind = CK_IntegralToFloating;
1136  return TC_Success;
1137  }
1138  }
1139  }
1140 
1141  // Reverse integral promotion/conversion. All such conversions are themselves
1142  // again integral promotions or conversions and are thus already handled by
1143  // p2 (TryDirectInitialization above).
1144  // (Note: any data loss warnings should be suppressed.)
1145  // The exception is the reverse of enum->integer, i.e. integer->enum (and
1146  // enum->enum). See also C++ 5.2.9p7.
1147  // The same goes for reverse floating point promotion/conversion and
1148  // floating-integral conversions. Again, only floating->enum is relevant.
1149  if (DestType->isEnumeralType()) {
1150  if (SrcType->isIntegralOrEnumerationType()) {
1151  Kind = CK_IntegralCast;
1152  return TC_Success;
1153  } else if (SrcType->isRealFloatingType()) {
1154  Kind = CK_FloatingToIntegral;
1155  return TC_Success;
1156  }
1157  }
1158 
1159  // Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
1160  // C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
1161  tcr = TryStaticPointerDowncast(Self, SrcType, DestType, CStyle, OpRange, msg,
1162  Kind, BasePath);
1163  if (tcr != TC_NotApplicable)
1164  return tcr;
1165 
1166  // Reverse member pointer conversion. C++ 4.11 specifies member pointer
1167  // conversion. C++ 5.2.9p9 has additional information.
1168  // DR54's access restrictions apply here also.
1169  tcr = TryStaticMemberPointerUpcast(Self, SrcExpr, SrcType, DestType, CStyle,
1170  OpRange, msg, Kind, BasePath);
1171  if (tcr != TC_NotApplicable)
1172  return tcr;
1173 
1174  // Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
1175  // void*. C++ 5.2.9p10 specifies additional restrictions, which really is
1176  // just the usual constness stuff.
1177  if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
1178  QualType SrcPointee = SrcPointer->getPointeeType();
1179  if (SrcPointee->isVoidType()) {
1180  if (const PointerType *DestPointer = DestType->getAs<PointerType>()) {
1181  QualType DestPointee = DestPointer->getPointeeType();
1182  if (DestPointee->isIncompleteOrObjectType()) {
1183  // This is definitely the intended conversion, but it might fail due
1184  // to a qualifier violation. Note that we permit Objective-C lifetime
1185  // and GC qualifier mismatches here.
1186  if (!CStyle) {
1187  Qualifiers DestPointeeQuals = DestPointee.getQualifiers();
1188  Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers();
1189  DestPointeeQuals.removeObjCGCAttr();
1190  DestPointeeQuals.removeObjCLifetime();
1191  SrcPointeeQuals.removeObjCGCAttr();
1192  SrcPointeeQuals.removeObjCLifetime();
1193  if (DestPointeeQuals != SrcPointeeQuals &&
1194  !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) {
1195  msg = diag::err_bad_cxx_cast_qualifiers_away;
1196  return TC_Failed;
1197  }
1198  }
1199  Kind = IsAddressSpaceConversion(SrcType, DestType)
1200  ? CK_AddressSpaceConversion
1201  : CK_BitCast;
1202  return TC_Success;
1203  }
1204 
1205  // Microsoft permits static_cast from 'pointer-to-void' to
1206  // 'pointer-to-function'.
1207  if (!CStyle && Self.getLangOpts().MSVCCompat &&
1208  DestPointee->isFunctionType()) {
1209  Self.Diag(OpRange.getBegin(), diag::ext_ms_cast_fn_obj) << OpRange;
1210  Kind = CK_BitCast;
1211  return TC_Success;
1212  }
1213  }
1214  else if (DestType->isObjCObjectPointerType()) {
1215  // allow both c-style cast and static_cast of objective-c pointers as
1216  // they are pervasive.
1217  Kind = CK_CPointerToObjCPointerCast;
1218  return TC_Success;
1219  }
1220  else if (CStyle && DestType->isBlockPointerType()) {
1221  // allow c-style cast of void * to block pointers.
1222  Kind = CK_AnyPointerToBlockPointerCast;
1223  return TC_Success;
1224  }
1225  }
1226  }
1227  // Allow arbitrary objective-c pointer conversion with static casts.
1228  if (SrcType->isObjCObjectPointerType() &&
1229  DestType->isObjCObjectPointerType()) {
1230  Kind = CK_BitCast;
1231  return TC_Success;
1232  }
1233  // Allow ns-pointer to cf-pointer conversion in either direction
1234  // with static casts.
1235  if (!CStyle &&
1236  Self.CheckTollFreeBridgeStaticCast(DestType, SrcExpr.get(), Kind))
1237  return TC_Success;
1238 
1239  // See if it looks like the user is trying to convert between
1240  // related record types, and select a better diagnostic if so.
1241  if (auto SrcPointer = SrcType->getAs<PointerType>())
1242  if (auto DestPointer = DestType->getAs<PointerType>())
1243  if (SrcPointer->getPointeeType()->getAs<RecordType>() &&
1244  DestPointer->getPointeeType()->getAs<RecordType>())
1245  msg = diag::err_bad_cxx_cast_unrelated_class;
1246 
1247  // We tried everything. Everything! Nothing works! :-(
1248  return TC_NotApplicable;
1249 }
1250 
1251 /// Tests whether a conversion according to N2844 is valid.
1253  QualType DestType, bool CStyle,
1254  CastKind &Kind, CXXCastPath &BasePath,
1255  unsigned &msg) {
1256  // C++11 [expr.static.cast]p3:
1257  // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
1258  // cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1259  const RValueReferenceType *R = DestType->getAs<RValueReferenceType>();
1260  if (!R)
1261  return TC_NotApplicable;
1262 
1263  if (!SrcExpr->isGLValue())
1264  return TC_NotApplicable;
1265 
1266  // Because we try the reference downcast before this function, from now on
1267  // this is the only cast possibility, so we issue an error if we fail now.
1268  // FIXME: Should allow casting away constness if CStyle.
1269  bool DerivedToBase;
1270  bool ObjCConversion;
1271  bool ObjCLifetimeConversion;
1272  QualType FromType = SrcExpr->getType();
1273  QualType ToType = R->getPointeeType();
1274  if (CStyle) {
1275  FromType = FromType.getUnqualifiedType();
1276  ToType = ToType.getUnqualifiedType();
1277  }
1278 
1280  SrcExpr->getBeginLoc(), ToType, FromType, DerivedToBase, ObjCConversion,
1281  ObjCLifetimeConversion);
1282  if (RefResult != Sema::Ref_Compatible) {
1283  if (CStyle || RefResult == Sema::Ref_Incompatible)
1284  return TC_NotApplicable;
1285  // Diagnose types which are reference-related but not compatible here since
1286  // we can provide better diagnostics. In these cases forwarding to
1287  // [expr.static.cast]p4 should never result in a well-formed cast.
1288  msg = SrcExpr->isLValue() ? diag::err_bad_lvalue_to_rvalue_cast
1289  : diag::err_bad_rvalue_to_rvalue_cast;
1290  return TC_Failed;
1291  }
1292 
1293  if (DerivedToBase) {
1294  Kind = CK_DerivedToBase;
1295  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1296  /*DetectVirtual=*/true);
1297  if (!Self.IsDerivedFrom(SrcExpr->getBeginLoc(), SrcExpr->getType(),
1298  R->getPointeeType(), Paths))
1299  return TC_NotApplicable;
1300 
1301  Self.BuildBasePathArray(Paths, BasePath);
1302  } else
1303  Kind = CK_NoOp;
1304 
1305  return TC_Success;
1306 }
1307 
1308 /// Tests whether a conversion according to C++ 5.2.9p5 is valid.
1310 TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType,
1311  bool CStyle, SourceRange OpRange,
1312  unsigned &msg, CastKind &Kind,
1313  CXXCastPath &BasePath) {
1314  // C++ 5.2.9p5: An lvalue of type "cv1 B", where B is a class type, can be
1315  // cast to type "reference to cv2 D", where D is a class derived from B,
1316  // if a valid standard conversion from "pointer to D" to "pointer to B"
1317  // exists, cv2 >= cv1, and B is not a virtual base class of D.
1318  // In addition, DR54 clarifies that the base must be accessible in the
1319  // current context. Although the wording of DR54 only applies to the pointer
1320  // variant of this rule, the intent is clearly for it to apply to the this
1321  // conversion as well.
1322 
1323  const ReferenceType *DestReference = DestType->getAs<ReferenceType>();
1324  if (!DestReference) {
1325  return TC_NotApplicable;
1326  }
1327  bool RValueRef = DestReference->isRValueReferenceType();
1328  if (!RValueRef && !SrcExpr->isLValue()) {
1329  // We know the left side is an lvalue reference, so we can suggest a reason.
1330  msg = diag::err_bad_cxx_cast_rvalue;
1331  return TC_NotApplicable;
1332  }
1333 
1334  QualType DestPointee = DestReference->getPointeeType();
1335 
1336  // FIXME: If the source is a prvalue, we should issue a warning (because the
1337  // cast always has undefined behavior), and for AST consistency, we should
1338  // materialize a temporary.
1339  return TryStaticDowncast(Self,
1340  Self.Context.getCanonicalType(SrcExpr->getType()),
1341  Self.Context.getCanonicalType(DestPointee), CStyle,
1342  OpRange, SrcExpr->getType(), DestType, msg, Kind,
1343  BasePath);
1344 }
1345 
1346 /// Tests whether a conversion according to C++ 5.2.9p8 is valid.
1349  bool CStyle, SourceRange OpRange,
1350  unsigned &msg, CastKind &Kind,
1351  CXXCastPath &BasePath) {
1352  // C++ 5.2.9p8: An rvalue of type "pointer to cv1 B", where B is a class
1353  // type, can be converted to an rvalue of type "pointer to cv2 D", where D
1354  // is a class derived from B, if a valid standard conversion from "pointer
1355  // to D" to "pointer to B" exists, cv2 >= cv1, and B is not a virtual base
1356  // class of D.
1357  // In addition, DR54 clarifies that the base must be accessible in the
1358  // current context.
1359 
1360  const PointerType *DestPointer = DestType->getAs<PointerType>();
1361  if (!DestPointer) {
1362  return TC_NotApplicable;
1363  }
1364 
1365  const PointerType *SrcPointer = SrcType->getAs<PointerType>();
1366  if (!SrcPointer) {
1367  msg = diag::err_bad_static_cast_pointer_nonpointer;
1368  return TC_NotApplicable;
1369  }
1370 
1371  return TryStaticDowncast(Self,
1372  Self.Context.getCanonicalType(SrcPointer->getPointeeType()),
1373  Self.Context.getCanonicalType(DestPointer->getPointeeType()),
1374  CStyle, OpRange, SrcType, DestType, msg, Kind,
1375  BasePath);
1376 }
1377 
1378 /// TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and
1379 /// TryStaticPointerDowncast. Tests whether a static downcast from SrcType to
1380 /// DestType is possible and allowed.
1383  bool CStyle, SourceRange OpRange, QualType OrigSrcType,
1384  QualType OrigDestType, unsigned &msg,
1385  CastKind &Kind, CXXCastPath &BasePath) {
1386  // We can only work with complete types. But don't complain if it doesn't work
1387  if (!Self.isCompleteType(OpRange.getBegin(), SrcType) ||
1388  !Self.isCompleteType(OpRange.getBegin(), DestType))
1389  return TC_NotApplicable;
1390 
1391  // Downcast can only happen in class hierarchies, so we need classes.
1392  if (!DestType->getAs<RecordType>() || !SrcType->getAs<RecordType>()) {
1393  return TC_NotApplicable;
1394  }
1395 
1396  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1397  /*DetectVirtual=*/true);
1398  if (!Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths)) {
1399  return TC_NotApplicable;
1400  }
1401 
1402  // Target type does derive from source type. Now we're serious. If an error
1403  // appears now, it's not ignored.
1404  // This may not be entirely in line with the standard. Take for example:
1405  // struct A {};
1406  // struct B : virtual A {
1407  // B(A&);
1408  // };
1409  //
1410  // void f()
1411  // {
1412  // (void)static_cast<const B&>(*((A*)0));
1413  // }
1414  // As far as the standard is concerned, p5 does not apply (A is virtual), so
1415  // p2 should be used instead - "const B& t(*((A*)0));" is perfectly valid.
1416  // However, both GCC and Comeau reject this example, and accepting it would
1417  // mean more complex code if we're to preserve the nice error message.
1418  // FIXME: Being 100% compliant here would be nice to have.
1419 
1420  // Must preserve cv, as always, unless we're in C-style mode.
1421  if (!CStyle && !DestType.isAtLeastAsQualifiedAs(SrcType)) {
1422  msg = diag::err_bad_cxx_cast_qualifiers_away;
1423  return TC_Failed;
1424  }
1425 
1426  if (Paths.isAmbiguous(SrcType.getUnqualifiedType())) {
1427  // This code is analoguous to that in CheckDerivedToBaseConversion, except
1428  // that it builds the paths in reverse order.
1429  // To sum up: record all paths to the base and build a nice string from
1430  // them. Use it to spice up the error message.
1431  if (!Paths.isRecordingPaths()) {
1432  Paths.clear();
1433  Paths.setRecordingPaths(true);
1434  Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths);
1435  }
1436  std::string PathDisplayStr;
1437  std::set<unsigned> DisplayedPaths;
1438  for (clang::CXXBasePath &Path : Paths) {
1439  if (DisplayedPaths.insert(Path.back().SubobjectNumber).second) {
1440  // We haven't displayed a path to this particular base
1441  // class subobject yet.
1442  PathDisplayStr += "\n ";
1443  for (CXXBasePathElement &PE : llvm::reverse(Path))
1444  PathDisplayStr += PE.Base->getType().getAsString() + " -> ";
1445  PathDisplayStr += QualType(DestType).getAsString();
1446  }
1447  }
1448 
1449  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_base_to_derived_cast)
1450  << QualType(SrcType).getUnqualifiedType()
1451  << QualType(DestType).getUnqualifiedType()
1452  << PathDisplayStr << OpRange;
1453  msg = 0;
1454  return TC_Failed;
1455  }
1456 
1457  if (Paths.getDetectedVirtual() != nullptr) {
1458  QualType VirtualBase(Paths.getDetectedVirtual(), 0);
1459  Self.Diag(OpRange.getBegin(), diag::err_static_downcast_via_virtual)
1460  << OrigSrcType << OrigDestType << VirtualBase << OpRange;
1461  msg = 0;
1462  return TC_Failed;
1463  }
1464 
1465  if (!CStyle) {
1466  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1467  SrcType, DestType,
1468  Paths.front(),
1469  diag::err_downcast_from_inaccessible_base)) {
1470  case Sema::AR_accessible:
1471  case Sema::AR_delayed: // be optimistic
1472  case Sema::AR_dependent: // be optimistic
1473  break;
1474 
1475  case Sema::AR_inaccessible:
1476  msg = 0;
1477  return TC_Failed;
1478  }
1479  }
1480 
1481  Self.BuildBasePathArray(Paths, BasePath);
1482  Kind = CK_BaseToDerived;
1483  return TC_Success;
1484 }
1485 
1486 /// TryStaticMemberPointerUpcast - Tests whether a conversion according to
1487 /// C++ 5.2.9p9 is valid:
1488 ///
1489 /// An rvalue of type "pointer to member of D of type cv1 T" can be
1490 /// converted to an rvalue of type "pointer to member of B of type cv2 T",
1491 /// where B is a base class of D [...].
1492 ///
1495  QualType DestType, bool CStyle,
1496  SourceRange OpRange,
1497  unsigned &msg, CastKind &Kind,
1498  CXXCastPath &BasePath) {
1499  const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>();
1500  if (!DestMemPtr)
1501  return TC_NotApplicable;
1502 
1503  bool WasOverloadedFunction = false;
1504  DeclAccessPair FoundOverload;
1505  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1506  if (FunctionDecl *Fn
1507  = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(), DestType, false,
1508  FoundOverload)) {
1509  CXXMethodDecl *M = cast<CXXMethodDecl>(Fn);
1510  SrcType = Self.Context.getMemberPointerType(Fn->getType(),
1511  Self.Context.getTypeDeclType(M->getParent()).getTypePtr());
1512  WasOverloadedFunction = true;
1513  }
1514  }
1515 
1516  const MemberPointerType *SrcMemPtr = SrcType->getAs<MemberPointerType>();
1517  if (!SrcMemPtr) {
1518  msg = diag::err_bad_static_cast_member_pointer_nonmp;
1519  return TC_NotApplicable;
1520  }
1521 
1522  // Lock down the inheritance model right now in MS ABI, whether or not the
1523  // pointee types are the same.
1524  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1525  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
1526  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
1527  }
1528 
1529  // T == T, modulo cv
1530  if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
1531  DestMemPtr->getPointeeType()))
1532  return TC_NotApplicable;
1533 
1534  // B base of D
1535  QualType SrcClass(SrcMemPtr->getClass(), 0);
1536  QualType DestClass(DestMemPtr->getClass(), 0);
1537  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1538  /*DetectVirtual=*/true);
1539  if (!Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths))
1540  return TC_NotApplicable;
1541 
1542  // B is a base of D. But is it an allowed base? If not, it's a hard error.
1543  if (Paths.isAmbiguous(Self.Context.getCanonicalType(DestClass))) {
1544  Paths.clear();
1545  Paths.setRecordingPaths(true);
1546  bool StillOkay =
1547  Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths);
1548  assert(StillOkay);
1549  (void)StillOkay;
1550  std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
1551  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
1552  << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
1553  msg = 0;
1554  return TC_Failed;
1555  }
1556 
1557  if (const RecordType *VBase = Paths.getDetectedVirtual()) {
1558  Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
1559  << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
1560  msg = 0;
1561  return TC_Failed;
1562  }
1563 
1564  if (!CStyle) {
1565  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1566  DestClass, SrcClass,
1567  Paths.front(),
1568  diag::err_upcast_to_inaccessible_base)) {
1569  case Sema::AR_accessible:
1570  case Sema::AR_delayed:
1571  case Sema::AR_dependent:
1572  // Optimistically assume that the delayed and dependent cases
1573  // will work out.
1574  break;
1575 
1576  case Sema::AR_inaccessible:
1577  msg = 0;
1578  return TC_Failed;
1579  }
1580  }
1581 
1582  if (WasOverloadedFunction) {
1583  // Resolve the address of the overloaded function again, this time
1584  // allowing complaints if something goes wrong.
1586  DestType,
1587  true,
1588  FoundOverload);
1589  if (!Fn) {
1590  msg = 0;
1591  return TC_Failed;
1592  }
1593 
1594  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr, FoundOverload, Fn);
1595  if (!SrcExpr.isUsable()) {
1596  msg = 0;
1597  return TC_Failed;
1598  }
1599  }
1600 
1601  Self.BuildBasePathArray(Paths, BasePath);
1602  Kind = CK_DerivedToBaseMemberPointer;
1603  return TC_Success;
1604 }
1605 
1606 /// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
1607 /// is valid:
1608 ///
1609 /// An expression e can be explicitly converted to a type T using a
1610 /// @c static_cast if the declaration "T t(e);" is well-formed [...].
1612 TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType,
1614  SourceRange OpRange, unsigned &msg,
1615  CastKind &Kind, bool ListInitialization) {
1616  if (DestType->isRecordType()) {
1617  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
1618  diag::err_bad_dynamic_cast_incomplete) ||
1619  Self.RequireNonAbstractType(OpRange.getBegin(), DestType,
1620  diag::err_allocation_of_abstract_type)) {
1621  msg = 0;
1622  return TC_Failed;
1623  }
1624  }
1625 
1627  InitializationKind InitKind
1628  = (CCK == Sema::CCK_CStyleCast)
1629  ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange,
1630  ListInitialization)
1631  : (CCK == Sema::CCK_FunctionalCast)
1632  ? InitializationKind::CreateFunctionalCast(OpRange, ListInitialization)
1633  : InitializationKind::CreateCast(OpRange);
1634  Expr *SrcExprRaw = SrcExpr.get();
1635  // FIXME: Per DR242, we should check for an implicit conversion sequence
1636  // or for a constructor that could be invoked by direct-initialization
1637  // here, not for an initialization sequence.
1638  InitializationSequence InitSeq(Self, Entity, InitKind, SrcExprRaw);
1639 
1640  // At this point of CheckStaticCast, if the destination is a reference,
1641  // or the expression is an overload expression this has to work.
1642  // There is no other way that works.
1643  // On the other hand, if we're checking a C-style cast, we've still got
1644  // the reinterpret_cast way.
1645  bool CStyle
1646  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1647  if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType()))
1648  return TC_NotApplicable;
1649 
1650  ExprResult Result = InitSeq.Perform(Self, Entity, InitKind, SrcExprRaw);
1651  if (Result.isInvalid()) {
1652  msg = 0;
1653  return TC_Failed;
1654  }
1655 
1656  if (InitSeq.isConstructorInitialization())
1657  Kind = CK_ConstructorConversion;
1658  else
1659  Kind = CK_NoOp;
1660 
1661  SrcExpr = Result;
1662  return TC_Success;
1663 }
1664 
1665 /// TryConstCast - See if a const_cast from source to destination is allowed,
1666 /// and perform it if it is.
1668  QualType DestType, bool CStyle,
1669  unsigned &msg) {
1670  DestType = Self.Context.getCanonicalType(DestType);
1671  QualType SrcType = SrcExpr.get()->getType();
1672  bool NeedToMaterializeTemporary = false;
1673 
1674  if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
1675  // C++11 5.2.11p4:
1676  // if a pointer to T1 can be explicitly converted to the type "pointer to
1677  // T2" using a const_cast, then the following conversions can also be
1678  // made:
1679  // -- an lvalue of type T1 can be explicitly converted to an lvalue of
1680  // type T2 using the cast const_cast<T2&>;
1681  // -- a glvalue of type T1 can be explicitly converted to an xvalue of
1682  // type T2 using the cast const_cast<T2&&>; and
1683  // -- if T1 is a class type, a prvalue of type T1 can be explicitly
1684  // converted to an xvalue of type T2 using the cast const_cast<T2&&>.
1685 
1686  if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr.get()->isLValue()) {
1687  // Cannot const_cast non-lvalue to lvalue reference type. But if this
1688  // is C-style, static_cast might find a way, so we simply suggest a
1689  // message and tell the parent to keep searching.
1690  msg = diag::err_bad_cxx_cast_rvalue;
1691  return TC_NotApplicable;
1692  }
1693 
1694  if (isa<RValueReferenceType>(DestTypeTmp) && SrcExpr.get()->isRValue()) {
1695  if (!SrcType->isRecordType()) {
1696  // Cannot const_cast non-class prvalue to rvalue reference type. But if
1697  // this is C-style, static_cast can do this.
1698  msg = diag::err_bad_cxx_cast_rvalue;
1699  return TC_NotApplicable;
1700  }
1701 
1702  // Materialize the class prvalue so that the const_cast can bind a
1703  // reference to it.
1704  NeedToMaterializeTemporary = true;
1705  }
1706 
1707  // It's not completely clear under the standard whether we can
1708  // const_cast bit-field gl-values. Doing so would not be
1709  // intrinsically complicated, but for now, we say no for
1710  // consistency with other compilers and await the word of the
1711  // committee.
1712  if (SrcExpr.get()->refersToBitField()) {
1713  msg = diag::err_bad_cxx_cast_bitfield;
1714  return TC_NotApplicable;
1715  }
1716 
1717  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
1718  SrcType = Self.Context.getPointerType(SrcType);
1719  }
1720 
1721  // C++ 5.2.11p5: For a const_cast involving pointers to data members [...]
1722  // the rules for const_cast are the same as those used for pointers.
1723 
1724  if (!DestType->isPointerType() &&
1725  !DestType->isMemberPointerType() &&
1726  !DestType->isObjCObjectPointerType()) {
1727  // Cannot cast to non-pointer, non-reference type. Note that, if DestType
1728  // was a reference type, we converted it to a pointer above.
1729  // The status of rvalue references isn't entirely clear, but it looks like
1730  // conversion to them is simply invalid.
1731  // C++ 5.2.11p3: For two pointer types [...]
1732  if (!CStyle)
1733  msg = diag::err_bad_const_cast_dest;
1734  return TC_NotApplicable;
1735  }
1736  if (DestType->isFunctionPointerType() ||
1737  DestType->isMemberFunctionPointerType()) {
1738  // Cannot cast direct function pointers.
1739  // C++ 5.2.11p2: [...] where T is any object type or the void type [...]
1740  // T is the ultimate pointee of source and target type.
1741  if (!CStyle)
1742  msg = diag::err_bad_const_cast_dest;
1743  return TC_NotApplicable;
1744  }
1745 
1746  // C++ [expr.const.cast]p3:
1747  // "For two similar types T1 and T2, [...]"
1748  //
1749  // We only allow a const_cast to change cvr-qualifiers, not other kinds of
1750  // type qualifiers. (Likewise, we ignore other changes when determining
1751  // whether a cast casts away constness.)
1752  if (!Self.Context.hasCvrSimilarType(SrcType, DestType))
1753  return TC_NotApplicable;
1754 
1755  if (NeedToMaterializeTemporary)
1756  // This is a const_cast from a class prvalue to an rvalue reference type.
1757  // Materialize a temporary to store the result of the conversion.
1758  SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcExpr.get()->getType(),
1759  SrcExpr.get(),
1760  /*IsLValueReference*/ false);
1761 
1762  return TC_Success;
1763 }
1764 
1765 // Checks for undefined behavior in reinterpret_cast.
1766 // The cases that is checked for is:
1767 // *reinterpret_cast<T*>(&a)
1768 // reinterpret_cast<T&>(a)
1769 // where accessing 'a' as type 'T' will result in undefined behavior.
1771  bool IsDereference,
1772  SourceRange Range) {
1773  unsigned DiagID = IsDereference ?
1774  diag::warn_pointer_indirection_from_incompatible_type :
1775  diag::warn_undefined_reinterpret_cast;
1776 
1777  if (Diags.isIgnored(DiagID, Range.getBegin()))
1778  return;
1779 
1780  QualType SrcTy, DestTy;
1781  if (IsDereference) {
1782  if (!SrcType->getAs<PointerType>() || !DestType->getAs<PointerType>()) {
1783  return;
1784  }
1785  SrcTy = SrcType->getPointeeType();
1786  DestTy = DestType->getPointeeType();
1787  } else {
1788  if (!DestType->getAs<ReferenceType>()) {
1789  return;
1790  }
1791  SrcTy = SrcType;
1792  DestTy = DestType->getPointeeType();
1793  }
1794 
1795  // Cast is compatible if the types are the same.
1796  if (Context.hasSameUnqualifiedType(DestTy, SrcTy)) {
1797  return;
1798  }
1799  // or one of the types is a char or void type
1800  if (DestTy->isAnyCharacterType() || DestTy->isVoidType() ||
1801  SrcTy->isAnyCharacterType() || SrcTy->isVoidType()) {
1802  return;
1803  }
1804  // or one of the types is a tag type.
1805  if (SrcTy->getAs<TagType>() || DestTy->getAs<TagType>()) {
1806  return;
1807  }
1808 
1809  // FIXME: Scoped enums?
1810  if ((SrcTy->isUnsignedIntegerType() && DestTy->isSignedIntegerType()) ||
1811  (SrcTy->isSignedIntegerType() && DestTy->isUnsignedIntegerType())) {
1812  if (Context.getTypeSize(DestTy) == Context.getTypeSize(SrcTy)) {
1813  return;
1814  }
1815  }
1816 
1817  Diag(Range.getBegin(), DiagID) << SrcType << DestType << Range;
1818 }
1819 
1820 static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr,
1821  QualType DestType) {
1822  QualType SrcType = SrcExpr.get()->getType();
1823  if (Self.Context.hasSameType(SrcType, DestType))
1824  return;
1825  if (const PointerType *SrcPtrTy = SrcType->getAs<PointerType>())
1826  if (SrcPtrTy->isObjCSelType()) {
1827  QualType DT = DestType;
1828  if (isa<PointerType>(DestType))
1829  DT = DestType->getPointeeType();
1830  if (!DT.getUnqualifiedType()->isVoidType())
1831  Self.Diag(SrcExpr.get()->getExprLoc(),
1832  diag::warn_cast_pointer_from_sel)
1833  << SrcType << DestType << SrcExpr.get()->getSourceRange();
1834  }
1835 }
1836 
1837 /// Diagnose casts that change the calling convention of a pointer to a function
1838 /// defined in the current TU.
1839 static void DiagnoseCallingConvCast(Sema &Self, const ExprResult &SrcExpr,
1840  QualType DstType, SourceRange OpRange) {
1841  // Check if this cast would change the calling convention of a function
1842  // pointer type.
1843  QualType SrcType = SrcExpr.get()->getType();
1844  if (Self.Context.hasSameType(SrcType, DstType) ||
1845  !SrcType->isFunctionPointerType() || !DstType->isFunctionPointerType())
1846  return;
1847  const auto *SrcFTy =
1848  SrcType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
1849  const auto *DstFTy =
1850  DstType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
1851  CallingConv SrcCC = SrcFTy->getCallConv();
1852  CallingConv DstCC = DstFTy->getCallConv();
1853  if (SrcCC == DstCC)
1854  return;
1855 
1856  // We have a calling convention cast. Check if the source is a pointer to a
1857  // known, specific function that has already been defined.
1858  Expr *Src = SrcExpr.get()->IgnoreParenImpCasts();
1859  if (auto *UO = dyn_cast<UnaryOperator>(Src))
1860  if (UO->getOpcode() == UO_AddrOf)
1861  Src = UO->getSubExpr()->IgnoreParenImpCasts();
1862  auto *DRE = dyn_cast<DeclRefExpr>(Src);
1863  if (!DRE)
1864  return;
1865  auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
1866  if (!FD)
1867  return;
1868 
1869  // Only warn if we are casting from the default convention to a non-default
1870  // convention. This can happen when the programmer forgot to apply the calling
1871  // convention to the function declaration and then inserted this cast to
1872  // satisfy the type system.
1874  FD->isVariadic(), FD->isCXXInstanceMember());
1875  if (DstCC == DefaultCC || SrcCC != DefaultCC)
1876  return;
1877 
1878  // Diagnose this cast, as it is probably bad.
1879  StringRef SrcCCName = FunctionType::getNameForCallConv(SrcCC);
1880  StringRef DstCCName = FunctionType::getNameForCallConv(DstCC);
1881  Self.Diag(OpRange.getBegin(), diag::warn_cast_calling_conv)
1882  << SrcCCName << DstCCName << OpRange;
1883 
1884  // The checks above are cheaper than checking if the diagnostic is enabled.
1885  // However, it's worth checking if the warning is enabled before we construct
1886  // a fixit.
1887  if (Self.Diags.isIgnored(diag::warn_cast_calling_conv, OpRange.getBegin()))
1888  return;
1889 
1890  // Try to suggest a fixit to change the calling convention of the function
1891  // whose address was taken. Try to use the latest macro for the convention.
1892  // For example, users probably want to write "WINAPI" instead of "__stdcall"
1893  // to match the Windows header declarations.
1894  SourceLocation NameLoc = FD->getFirstDecl()->getNameInfo().getLoc();
1895  Preprocessor &PP = Self.getPreprocessor();
1896  SmallVector<TokenValue, 6> AttrTokens;
1897  SmallString<64> CCAttrText;
1898  llvm::raw_svector_ostream OS(CCAttrText);
1899  if (Self.getLangOpts().MicrosoftExt) {
1900  // __stdcall or __vectorcall
1901  OS << "__" << DstCCName;
1902  IdentifierInfo *II = PP.getIdentifierInfo(OS.str());
1903  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
1904  ? TokenValue(II->getTokenID())
1905  : TokenValue(II));
1906  } else {
1907  // __attribute__((stdcall)) or __attribute__((vectorcall))
1908  OS << "__attribute__((" << DstCCName << "))";
1909  AttrTokens.push_back(tok::kw___attribute);
1910  AttrTokens.push_back(tok::l_paren);
1911  AttrTokens.push_back(tok::l_paren);
1912  IdentifierInfo *II = PP.getIdentifierInfo(DstCCName);
1913  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
1914  ? TokenValue(II->getTokenID())
1915  : TokenValue(II));
1916  AttrTokens.push_back(tok::r_paren);
1917  AttrTokens.push_back(tok::r_paren);
1918  }
1919  StringRef AttrSpelling = PP.getLastMacroWithSpelling(NameLoc, AttrTokens);
1920  if (!AttrSpelling.empty())
1921  CCAttrText = AttrSpelling;
1922  OS << ' ';
1923  Self.Diag(NameLoc, diag::note_change_calling_conv_fixit)
1924  << FD << DstCCName << FixItHint::CreateInsertion(NameLoc, CCAttrText);
1925 }
1926 
1927 static void checkIntToPointerCast(bool CStyle, SourceLocation Loc,
1928  const Expr *SrcExpr, QualType DestType,
1929  Sema &Self) {
1930  QualType SrcType = SrcExpr->getType();
1931 
1932  // Not warning on reinterpret_cast, boolean, constant expressions, etc
1933  // are not explicit design choices, but consistent with GCC's behavior.
1934  // Feel free to modify them if you've reason/evidence for an alternative.
1935  if (CStyle && SrcType->isIntegralType(Self.Context)
1936  && !SrcType->isBooleanType()
1937  && !SrcType->isEnumeralType()
1938  && !SrcExpr->isIntegerConstantExpr(Self.Context)
1939  && Self.Context.getTypeSize(DestType) >
1940  Self.Context.getTypeSize(SrcType)) {
1941  // Separate between casts to void* and non-void* pointers.
1942  // Some APIs use (abuse) void* for something like a user context,
1943  // and often that value is an integer even if it isn't a pointer itself.
1944  // Having a separate warning flag allows users to control the warning
1945  // for their workflow.
1946  unsigned Diag = DestType->isVoidPointerType() ?
1947  diag::warn_int_to_void_pointer_cast
1948  : diag::warn_int_to_pointer_cast;
1949  Self.Diag(Loc, Diag) << SrcType << DestType;
1950  }
1951 }
1952 
1953 static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType,
1954  ExprResult &Result) {
1955  // We can only fix an overloaded reinterpret_cast if
1956  // - it is a template with explicit arguments that resolves to an lvalue
1957  // unambiguously, or
1958  // - it is the only function in an overload set that may have its address
1959  // taken.
1960 
1961  Expr *E = Result.get();
1962  // TODO: what if this fails because of DiagnoseUseOfDecl or something
1963  // like it?
1965  Result,
1966  Expr::getValueKindForType(DestType) == VK_RValue // Convert Fun to Ptr
1967  ) &&
1968  Result.isUsable())
1969  return true;
1970 
1971  // No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
1972  // preserves Result.
1973  Result = E;
1975  Result, /*DoFunctionPointerConversion=*/true))
1976  return false;
1977  return Result.isUsable();
1978 }
1979 
1981  QualType DestType, bool CStyle,
1982  SourceRange OpRange,
1983  unsigned &msg,
1984  CastKind &Kind) {
1985  bool IsLValueCast = false;
1986 
1987  DestType = Self.Context.getCanonicalType(DestType);
1988  QualType SrcType = SrcExpr.get()->getType();
1989 
1990  // Is the source an overloaded name? (i.e. &foo)
1991  // If so, reinterpret_cast generally can not help us here (13.4, p1, bullet 5)
1992  if (SrcType == Self.Context.OverloadTy) {
1993  ExprResult FixedExpr = SrcExpr;
1994  if (!fixOverloadedReinterpretCastExpr(Self, DestType, FixedExpr))
1995  return TC_NotApplicable;
1996 
1997  assert(FixedExpr.isUsable() && "Invalid result fixing overloaded expr");
1998  SrcExpr = FixedExpr;
1999  SrcType = SrcExpr.get()->getType();
2000  }
2001 
2002  if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
2003  if (!SrcExpr.get()->isGLValue()) {
2004  // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
2005  // similar comment in const_cast.
2006  msg = diag::err_bad_cxx_cast_rvalue;
2007  return TC_NotApplicable;
2008  }
2009 
2010  if (!CStyle) {
2011  Self.CheckCompatibleReinterpretCast(SrcType, DestType,
2012  /*isDereference=*/false, OpRange);
2013  }
2014 
2015  // C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
2016  // same effect as the conversion *reinterpret_cast<T*>(&x) with the
2017  // built-in & and * operators.
2018 
2019  const char *inappropriate = nullptr;
2020  switch (SrcExpr.get()->getObjectKind()) {
2021  case OK_Ordinary:
2022  break;
2023  case OK_BitField:
2024  msg = diag::err_bad_cxx_cast_bitfield;
2025  return TC_NotApplicable;
2026  // FIXME: Use a specific diagnostic for the rest of these cases.
2027  case OK_VectorComponent: inappropriate = "vector element"; break;
2028  case OK_ObjCProperty: inappropriate = "property expression"; break;
2029  case OK_ObjCSubscript: inappropriate = "container subscripting expression";
2030  break;
2031  }
2032  if (inappropriate) {
2033  Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
2034  << inappropriate << DestType
2035  << OpRange << SrcExpr.get()->getSourceRange();
2036  msg = 0; SrcExpr = ExprError();
2037  return TC_NotApplicable;
2038  }
2039 
2040  // This code does this transformation for the checked types.
2041  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
2042  SrcType = Self.Context.getPointerType(SrcType);
2043 
2044  IsLValueCast = true;
2045  }
2046 
2047  // Canonicalize source for comparison.
2048  SrcType = Self.Context.getCanonicalType(SrcType);
2049 
2050  const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>(),
2051  *SrcMemPtr = SrcType->getAs<MemberPointerType>();
2052  if (DestMemPtr && SrcMemPtr) {
2053  // C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
2054  // can be explicitly converted to an rvalue of type "pointer to member
2055  // of Y of type T2" if T1 and T2 are both function types or both object
2056  // types.
2057  if (DestMemPtr->isMemberFunctionPointer() !=
2058  SrcMemPtr->isMemberFunctionPointer())
2059  return TC_NotApplicable;
2060 
2061  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2062  // We need to determine the inheritance model that the class will use if
2063  // haven't yet.
2064  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
2065  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
2066  }
2067 
2068  // Don't allow casting between member pointers of different sizes.
2069  if (Self.Context.getTypeSize(DestMemPtr) !=
2070  Self.Context.getTypeSize(SrcMemPtr)) {
2071  msg = diag::err_bad_cxx_cast_member_pointer_size;
2072  return TC_Failed;
2073  }
2074 
2075  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
2076  // constness.
2077  // A reinterpret_cast followed by a const_cast can, though, so in C-style,
2078  // we accept it.
2079  if (auto CACK =
2080  CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2081  /*CheckObjCLifetime=*/CStyle))
2082  return getCastAwayConstnessCastKind(CACK, msg);
2083 
2084  // A valid member pointer cast.
2085  assert(!IsLValueCast);
2086  Kind = CK_ReinterpretMemberPointer;
2087  return TC_Success;
2088  }
2089 
2090  // See below for the enumeral issue.
2091  if (SrcType->isNullPtrType() && DestType->isIntegralType(Self.Context)) {
2092  // C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
2093  // type large enough to hold it. A value of std::nullptr_t can be
2094  // converted to an integral type; the conversion has the same meaning
2095  // and validity as a conversion of (void*)0 to the integral type.
2096  if (Self.Context.getTypeSize(SrcType) >
2097  Self.Context.getTypeSize(DestType)) {
2098  msg = diag::err_bad_reinterpret_cast_small_int;
2099  return TC_Failed;
2100  }
2101  Kind = CK_PointerToIntegral;
2102  return TC_Success;
2103  }
2104 
2105  // Allow reinterpret_casts between vectors of the same size and
2106  // between vectors and integers of the same size.
2107  bool destIsVector = DestType->isVectorType();
2108  bool srcIsVector = SrcType->isVectorType();
2109  if (srcIsVector || destIsVector) {
2110  // The non-vector type, if any, must have integral type. This is
2111  // the same rule that C vector casts use; note, however, that enum
2112  // types are not integral in C++.
2113  if ((!destIsVector && !DestType->isIntegralType(Self.Context)) ||
2114  (!srcIsVector && !SrcType->isIntegralType(Self.Context)))
2115  return TC_NotApplicable;
2116 
2117  // The size we want to consider is eltCount * eltSize.
2118  // That's exactly what the lax-conversion rules will check.
2119  if (Self.areLaxCompatibleVectorTypes(SrcType, DestType)) {
2120  Kind = CK_BitCast;
2121  return TC_Success;
2122  }
2123 
2124  // Otherwise, pick a reasonable diagnostic.
2125  if (!destIsVector)
2126  msg = diag::err_bad_cxx_cast_vector_to_scalar_different_size;
2127  else if (!srcIsVector)
2128  msg = diag::err_bad_cxx_cast_scalar_to_vector_different_size;
2129  else
2130  msg = diag::err_bad_cxx_cast_vector_to_vector_different_size;
2131 
2132  return TC_Failed;
2133  }
2134 
2135  if (SrcType == DestType) {
2136  // C++ 5.2.10p2 has a note that mentions that, subject to all other
2137  // restrictions, a cast to the same type is allowed so long as it does not
2138  // cast away constness. In C++98, the intent was not entirely clear here,
2139  // since all other paragraphs explicitly forbid casts to the same type.
2140  // C++11 clarifies this case with p2.
2141  //
2142  // The only allowed types are: integral, enumeration, pointer, or
2143  // pointer-to-member types. We also won't restrict Obj-C pointers either.
2144  Kind = CK_NoOp;
2146  if (SrcType->isIntegralOrEnumerationType() ||
2147  SrcType->isAnyPointerType() ||
2148  SrcType->isMemberPointerType() ||
2149  SrcType->isBlockPointerType()) {
2150  Result = TC_Success;
2151  }
2152  return Result;
2153  }
2154 
2155  bool destIsPtr = DestType->isAnyPointerType() ||
2156  DestType->isBlockPointerType();
2157  bool srcIsPtr = SrcType->isAnyPointerType() ||
2158  SrcType->isBlockPointerType();
2159  if (!destIsPtr && !srcIsPtr) {
2160  // Except for std::nullptr_t->integer and lvalue->reference, which are
2161  // handled above, at least one of the two arguments must be a pointer.
2162  return TC_NotApplicable;
2163  }
2164 
2165  if (DestType->isIntegralType(Self.Context)) {
2166  assert(srcIsPtr && "One type must be a pointer");
2167  // C++ 5.2.10p4: A pointer can be explicitly converted to any integral
2168  // type large enough to hold it; except in Microsoft mode, where the
2169  // integral type size doesn't matter (except we don't allow bool).
2170  bool MicrosoftException = Self.getLangOpts().MicrosoftExt &&
2171  !DestType->isBooleanType();
2172  if ((Self.Context.getTypeSize(SrcType) >
2173  Self.Context.getTypeSize(DestType)) &&
2174  !MicrosoftException) {
2175  msg = diag::err_bad_reinterpret_cast_small_int;
2176  return TC_Failed;
2177  }
2178  Kind = CK_PointerToIntegral;
2179  return TC_Success;
2180  }
2181 
2182  if (SrcType->isIntegralOrEnumerationType()) {
2183  assert(destIsPtr && "One type must be a pointer");
2184  checkIntToPointerCast(CStyle, OpRange.getBegin(), SrcExpr.get(), DestType,
2185  Self);
2186  // C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
2187  // converted to a pointer.
2188  // C++ 5.2.10p9: [Note: ...a null pointer constant of integral type is not
2189  // necessarily converted to a null pointer value.]
2190  Kind = CK_IntegralToPointer;
2191  return TC_Success;
2192  }
2193 
2194  if (!destIsPtr || !srcIsPtr) {
2195  // With the valid non-pointer conversions out of the way, we can be even
2196  // more stringent.
2197  return TC_NotApplicable;
2198  }
2199 
2200  // Cannot convert between block pointers and Objective-C object pointers.
2201  if ((SrcType->isBlockPointerType() && DestType->isObjCObjectPointerType()) ||
2202  (DestType->isBlockPointerType() && SrcType->isObjCObjectPointerType()))
2203  return TC_NotApplicable;
2204 
2205  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
2206  // The C-style cast operator can.
2207  TryCastResult SuccessResult = TC_Success;
2208  if (auto CACK =
2209  CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2210  /*CheckObjCLifetime=*/CStyle))
2211  SuccessResult = getCastAwayConstnessCastKind(CACK, msg);
2212 
2213  if (IsLValueCast) {
2214  Kind = CK_LValueBitCast;
2215  } else if (DestType->isObjCObjectPointerType()) {
2216  Kind = Self.PrepareCastToObjCObjectPointer(SrcExpr);
2217  } else if (DestType->isBlockPointerType()) {
2218  if (!SrcType->isBlockPointerType()) {
2219  Kind = CK_AnyPointerToBlockPointerCast;
2220  } else {
2221  Kind = CK_BitCast;
2222  }
2223  } else if (IsAddressSpaceConversion(SrcType, DestType)) {
2224  Kind = CK_AddressSpaceConversion;
2225  } else {
2226  Kind = CK_BitCast;
2227  }
2228 
2229  // Any pointer can be cast to an Objective-C pointer type with a C-style
2230  // cast.
2231  if (CStyle && DestType->isObjCObjectPointerType()) {
2232  return SuccessResult;
2233  }
2234  if (CStyle)
2235  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2236 
2237  DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
2238 
2239  // Not casting away constness, so the only remaining check is for compatible
2240  // pointer categories.
2241 
2242  if (SrcType->isFunctionPointerType()) {
2243  if (DestType->isFunctionPointerType()) {
2244  // C++ 5.2.10p6: A pointer to a function can be explicitly converted to
2245  // a pointer to a function of a different type.
2246  return SuccessResult;
2247  }
2248 
2249  // C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
2250  // an object type or vice versa is conditionally-supported.
2251  // Compilers support it in C++03 too, though, because it's necessary for
2252  // casting the return value of dlsym() and GetProcAddress().
2253  // FIXME: Conditionally-supported behavior should be configurable in the
2254  // TargetInfo or similar.
2255  Self.Diag(OpRange.getBegin(),
2256  Self.getLangOpts().CPlusPlus11 ?
2257  diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2258  << OpRange;
2259  return SuccessResult;
2260  }
2261 
2262  if (DestType->isFunctionPointerType()) {
2263  // See above.
2264  Self.Diag(OpRange.getBegin(),
2265  Self.getLangOpts().CPlusPlus11 ?
2266  diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2267  << OpRange;
2268  return SuccessResult;
2269  }
2270 
2271  // C++ 5.2.10p7: A pointer to an object can be explicitly converted to
2272  // a pointer to an object of different type.
2273  // Void pointers are not specified, but supported by every compiler out there.
2274  // So we finish by allowing everything that remains - it's got to be two
2275  // object pointers.
2276  return SuccessResult;
2277 }
2278 
2279 void CastOperation::CheckCXXCStyleCast(bool FunctionalStyle,
2280  bool ListInitialization) {
2281  assert(Self.getLangOpts().CPlusPlus);
2282 
2283  // Handle placeholders.
2284  if (isPlaceholder()) {
2285  // C-style casts can resolve __unknown_any types.
2286  if (claimPlaceholder(BuiltinType::UnknownAny)) {
2287  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2288  SrcExpr.get(), Kind,
2289  ValueKind, BasePath);
2290  return;
2291  }
2292 
2293  checkNonOverloadPlaceholders();
2294  if (SrcExpr.isInvalid())
2295  return;
2296  }
2297 
2298  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
2299  // This test is outside everything else because it's the only case where
2300  // a non-lvalue-reference target type does not lead to decay.
2301  if (DestType->isVoidType()) {
2302  Kind = CK_ToVoid;
2303 
2304  if (claimPlaceholder(BuiltinType::Overload)) {
2306  SrcExpr, /* Decay Function to ptr */ false,
2307  /* Complain */ true, DestRange, DestType,
2308  diag::err_bad_cstyle_cast_overload);
2309  if (SrcExpr.isInvalid())
2310  return;
2311  }
2312 
2313  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2314  return;
2315  }
2316 
2317  // If the type is dependent, we won't do any other semantic analysis now.
2318  if (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
2319  SrcExpr.get()->isValueDependent()) {
2320  assert(Kind == CK_Dependent);
2321  return;
2322  }
2323 
2324  if (ValueKind == VK_RValue && !DestType->isRecordType() &&
2325  !isPlaceholder(BuiltinType::Overload)) {
2326  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2327  if (SrcExpr.isInvalid())
2328  return;
2329  }
2330 
2331  // AltiVec vector initialization with a single literal.
2332  if (const VectorType *vecTy = DestType->getAs<VectorType>())
2333  if (vecTy->getVectorKind() == VectorType::AltiVecVector
2334  && (SrcExpr.get()->getType()->isIntegerType()
2335  || SrcExpr.get()->getType()->isFloatingType())) {
2336  Kind = CK_VectorSplat;
2337  SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2338  return;
2339  }
2340 
2341  // C++ [expr.cast]p5: The conversions performed by
2342  // - a const_cast,
2343  // - a static_cast,
2344  // - a static_cast followed by a const_cast,
2345  // - a reinterpret_cast, or
2346  // - a reinterpret_cast followed by a const_cast,
2347  // can be performed using the cast notation of explicit type conversion.
2348  // [...] If a conversion can be interpreted in more than one of the ways
2349  // listed above, the interpretation that appears first in the list is used,
2350  // even if a cast resulting from that interpretation is ill-formed.
2351  // In plain language, this means trying a const_cast ...
2352  unsigned msg = diag::err_bad_cxx_cast_generic;
2353  TryCastResult tcr = TryConstCast(Self, SrcExpr, DestType,
2354  /*CStyle*/true, msg);
2355  if (SrcExpr.isInvalid())
2356  return;
2357  if (isValidCast(tcr))
2358  Kind = CK_NoOp;
2359 
2361  = FunctionalStyle? Sema::CCK_FunctionalCast
2363  if (tcr == TC_NotApplicable) {
2364  // ... or if that is not possible, a static_cast, ignoring const, ...
2365  tcr = TryStaticCast(Self, SrcExpr, DestType, CCK, OpRange,
2366  msg, Kind, BasePath, ListInitialization);
2367  if (SrcExpr.isInvalid())
2368  return;
2369 
2370  if (tcr == TC_NotApplicable) {
2371  // ... and finally a reinterpret_cast, ignoring const.
2372  tcr = TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/true,
2373  OpRange, msg, Kind);
2374  if (SrcExpr.isInvalid())
2375  return;
2376  }
2377  }
2378 
2380  isValidCast(tcr))
2381  checkObjCConversion(CCK);
2382 
2383  if (tcr != TC_Success && msg != 0) {
2384  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2385  DeclAccessPair Found;
2387  DestType,
2388  /*Complain*/ true,
2389  Found);
2390  if (Fn) {
2391  // If DestType is a function type (not to be confused with the function
2392  // pointer type), it will be possible to resolve the function address,
2393  // but the type cast should be considered as failure.
2394  OverloadExpr *OE = OverloadExpr::find(SrcExpr.get()).Expression;
2395  Self.Diag(OpRange.getBegin(), diag::err_bad_cstyle_cast_overload)
2396  << OE->getName() << DestType << OpRange
2397  << OE->getQualifierLoc().getSourceRange();
2398  Self.NoteAllOverloadCandidates(SrcExpr.get());
2399  }
2400  } else {
2401  diagnoseBadCast(Self, msg, (FunctionalStyle ? CT_Functional : CT_CStyle),
2402  OpRange, SrcExpr.get(), DestType, ListInitialization);
2403  }
2404  }
2405 
2406  if (isValidCast(tcr)) {
2407  if (Kind == CK_BitCast)
2408  checkCastAlign();
2409  } else {
2410  SrcExpr = ExprError();
2411  }
2412 }
2413 
2414 /// DiagnoseBadFunctionCast - Warn whenever a function call is cast to a
2415 /// non-matching type. Such as enum function call to int, int call to
2416 /// pointer; etc. Cast to 'void' is an exception.
2417 static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr,
2418  QualType DestType) {
2419  if (Self.Diags.isIgnored(diag::warn_bad_function_cast,
2420  SrcExpr.get()->getExprLoc()))
2421  return;
2422 
2423  if (!isa<CallExpr>(SrcExpr.get()))
2424  return;
2425 
2426  QualType SrcType = SrcExpr.get()->getType();
2427  if (DestType.getUnqualifiedType()->isVoidType())
2428  return;
2429  if ((SrcType->isAnyPointerType() || SrcType->isBlockPointerType())
2430  && (DestType->isAnyPointerType() || DestType->isBlockPointerType()))
2431  return;
2432  if (SrcType->isIntegerType() && DestType->isIntegerType() &&
2433  (SrcType->isBooleanType() == DestType->isBooleanType()) &&
2434  (SrcType->isEnumeralType() == DestType->isEnumeralType()))
2435  return;
2436  if (SrcType->isRealFloatingType() && DestType->isRealFloatingType())
2437  return;
2438  if (SrcType->isEnumeralType() && DestType->isEnumeralType())
2439  return;
2440  if (SrcType->isComplexType() && DestType->isComplexType())
2441  return;
2442  if (SrcType->isComplexIntegerType() && DestType->isComplexIntegerType())
2443  return;
2444 
2445  Self.Diag(SrcExpr.get()->getExprLoc(),
2446  diag::warn_bad_function_cast)
2447  << SrcType << DestType << SrcExpr.get()->getSourceRange();
2448 }
2449 
2450 /// Check the semantics of a C-style cast operation, in C.
2451 void CastOperation::CheckCStyleCast() {
2452  assert(!Self.getLangOpts().CPlusPlus);
2453 
2454  // C-style casts can resolve __unknown_any types.
2455  if (claimPlaceholder(BuiltinType::UnknownAny)) {
2456  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2457  SrcExpr.get(), Kind,
2458  ValueKind, BasePath);
2459  return;
2460  }
2461 
2462  // C99 6.5.4p2: the cast type needs to be void or scalar and the expression
2463  // type needs to be scalar.
2464  if (DestType->isVoidType()) {
2465  // We don't necessarily do lvalue-to-rvalue conversions on this.
2466  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2467  if (SrcExpr.isInvalid())
2468  return;
2469 
2470  // Cast to void allows any expr type.
2471  Kind = CK_ToVoid;
2472  return;
2473  }
2474 
2475  // Overloads are allowed with C extensions, so we need to support them.
2476  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2477  DeclAccessPair DAP;
2479  SrcExpr.get(), DestType, /*Complain=*/true, DAP))
2480  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr.get(), DAP, FD);
2481  else
2482  return;
2483  assert(SrcExpr.isUsable());
2484  }
2485  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2486  if (SrcExpr.isInvalid())
2487  return;
2488  QualType SrcType = SrcExpr.get()->getType();
2489 
2490  assert(!SrcType->isPlaceholderType());
2491 
2492  // OpenCL v1 s6.5: Casting a pointer to address space A to a pointer to
2493  // address space B is illegal.
2494  if (Self.getLangOpts().OpenCL && DestType->isPointerType() &&
2495  SrcType->isPointerType()) {
2496  const PointerType *DestPtr = DestType->getAs<PointerType>();
2497  if (!DestPtr->isAddressSpaceOverlapping(*SrcType->getAs<PointerType>())) {
2498  Self.Diag(OpRange.getBegin(),
2499  diag::err_typecheck_incompatible_address_space)
2500  << SrcType << DestType << Sema::AA_Casting
2501  << SrcExpr.get()->getSourceRange();
2502  SrcExpr = ExprError();
2503  return;
2504  }
2505  }
2506 
2507  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
2508  diag::err_typecheck_cast_to_incomplete)) {
2509  SrcExpr = ExprError();
2510  return;
2511  }
2512 
2513  if (!DestType->isScalarType() && !DestType->isVectorType()) {
2514  const RecordType *DestRecordTy = DestType->getAs<RecordType>();
2515 
2516  if (DestRecordTy && Self.Context.hasSameUnqualifiedType(DestType, SrcType)){
2517  // GCC struct/union extension: allow cast to self.
2518  Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_nonscalar)
2519  << DestType << SrcExpr.get()->getSourceRange();
2520  Kind = CK_NoOp;
2521  return;
2522  }
2523 
2524  // GCC's cast to union extension.
2525  if (DestRecordTy && DestRecordTy->getDecl()->isUnion()) {
2526  RecordDecl *RD = DestRecordTy->getDecl();
2527  if (CastExpr::getTargetFieldForToUnionCast(RD, SrcType)) {
2528  Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_to_union)
2529  << SrcExpr.get()->getSourceRange();
2530  Kind = CK_ToUnion;
2531  return;
2532  } else {
2533  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cast_to_union_no_type)
2534  << SrcType << SrcExpr.get()->getSourceRange();
2535  SrcExpr = ExprError();
2536  return;
2537  }
2538  }
2539 
2540  // OpenCL v2.0 s6.13.10 - Allow casts from '0' to event_t type.
2541  if (Self.getLangOpts().OpenCL && DestType->isEventT()) {
2542  llvm::APSInt CastInt;
2543  if (SrcExpr.get()->EvaluateAsInt(CastInt, Self.Context)) {
2544  if (0 == CastInt) {
2545  Kind = CK_ZeroToOCLEvent;
2546  return;
2547  }
2548  Self.Diag(OpRange.getBegin(),
2549  diag::err_opencl_cast_non_zero_to_event_t)
2550  << CastInt.toString(10) << SrcExpr.get()->getSourceRange();
2551  SrcExpr = ExprError();
2552  return;
2553  }
2554  }
2555 
2556  // Reject any other conversions to non-scalar types.
2557  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cond_expect_scalar)
2558  << DestType << SrcExpr.get()->getSourceRange();
2559  SrcExpr = ExprError();
2560  return;
2561  }
2562 
2563  // The type we're casting to is known to be a scalar or vector.
2564 
2565  // Require the operand to be a scalar or vector.
2566  if (!SrcType->isScalarType() && !SrcType->isVectorType()) {
2567  Self.Diag(SrcExpr.get()->getExprLoc(),
2568  diag::err_typecheck_expect_scalar_operand)
2569  << SrcType << SrcExpr.get()->getSourceRange();
2570  SrcExpr = ExprError();
2571  return;
2572  }
2573 
2574  if (DestType->isExtVectorType()) {
2575  SrcExpr = Self.CheckExtVectorCast(OpRange, DestType, SrcExpr.get(), Kind);
2576  return;
2577  }
2578 
2579  if (const VectorType *DestVecTy = DestType->getAs<VectorType>()) {
2580  if (DestVecTy->getVectorKind() == VectorType::AltiVecVector &&
2581  (SrcType->isIntegerType() || SrcType->isFloatingType())) {
2582  Kind = CK_VectorSplat;
2583  SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2584  } else if (Self.CheckVectorCast(OpRange, DestType, SrcType, Kind)) {
2585  SrcExpr = ExprError();
2586  }
2587  return;
2588  }
2589 
2590  if (SrcType->isVectorType()) {
2591  if (Self.CheckVectorCast(OpRange, SrcType, DestType, Kind))
2592  SrcExpr = ExprError();
2593  return;
2594  }
2595 
2596  // The source and target types are both scalars, i.e.
2597  // - arithmetic types (fundamental, enum, and complex)
2598  // - all kinds of pointers
2599  // Note that member pointers were filtered out with C++, above.
2600 
2601  if (isa<ObjCSelectorExpr>(SrcExpr.get())) {
2602  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_selector_expr);
2603  SrcExpr = ExprError();
2604  return;
2605  }
2606 
2607  // If either type is a pointer, the other type has to be either an
2608  // integer or a pointer.
2609  if (!DestType->isArithmeticType()) {
2610  if (!SrcType->isIntegralType(Self.Context) && SrcType->isArithmeticType()) {
2611  Self.Diag(SrcExpr.get()->getExprLoc(),
2612  diag::err_cast_pointer_from_non_pointer_int)
2613  << SrcType << SrcExpr.get()->getSourceRange();
2614  SrcExpr = ExprError();
2615  return;
2616  }
2617  checkIntToPointerCast(/* CStyle */ true, OpRange.getBegin(), SrcExpr.get(),
2618  DestType, Self);
2619  } else if (!SrcType->isArithmeticType()) {
2620  if (!DestType->isIntegralType(Self.Context) &&
2621  DestType->isArithmeticType()) {
2622  Self.Diag(SrcExpr.get()->getBeginLoc(),
2623  diag::err_cast_pointer_to_non_pointer_int)
2624  << DestType << SrcExpr.get()->getSourceRange();
2625  SrcExpr = ExprError();
2626  return;
2627  }
2628  }
2629 
2630  if (Self.getLangOpts().OpenCL &&
2631  !Self.getOpenCLOptions().isEnabled("cl_khr_fp16")) {
2632  if (DestType->isHalfType()) {
2633  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::err_opencl_cast_to_half)
2634  << DestType << SrcExpr.get()->getSourceRange();
2635  SrcExpr = ExprError();
2636  return;
2637  }
2638  }
2639 
2640  // ARC imposes extra restrictions on casts.
2642  checkObjCConversion(Sema::CCK_CStyleCast);
2643  if (SrcExpr.isInvalid())
2644  return;
2645 
2646  const PointerType *CastPtr = DestType->getAs<PointerType>();
2647  if (Self.getLangOpts().ObjCAutoRefCount && CastPtr) {
2648  if (const PointerType *ExprPtr = SrcType->getAs<PointerType>()) {
2649  Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers();
2650  Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers();
2651  if (CastPtr->getPointeeType()->isObjCLifetimeType() &&
2652  ExprPtr->getPointeeType()->isObjCLifetimeType() &&
2653  !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) {
2654  Self.Diag(SrcExpr.get()->getBeginLoc(),
2655  diag::err_typecheck_incompatible_ownership)
2656  << SrcType << DestType << Sema::AA_Casting
2657  << SrcExpr.get()->getSourceRange();
2658  return;
2659  }
2660  }
2661  }
2662  else if (!Self.CheckObjCARCUnavailableWeakConversion(DestType, SrcType)) {
2663  Self.Diag(SrcExpr.get()->getBeginLoc(),
2664  diag::err_arc_convesion_of_weak_unavailable)
2665  << 1 << SrcType << DestType << SrcExpr.get()->getSourceRange();
2666  SrcExpr = ExprError();
2667  return;
2668  }
2669  }
2670 
2671  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2672  DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
2673  DiagnoseBadFunctionCast(Self, SrcExpr, DestType);
2674  Kind = Self.PrepareScalarCast(SrcExpr, DestType);
2675  if (SrcExpr.isInvalid())
2676  return;
2677 
2678  if (Kind == CK_BitCast)
2679  checkCastAlign();
2680 }
2681 
2682 /// DiagnoseCastQual - Warn whenever casts discards a qualifiers, be it either
2683 /// const, volatile or both.
2684 static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
2685  QualType DestType) {
2686  if (SrcExpr.isInvalid())
2687  return;
2688 
2689  QualType SrcType = SrcExpr.get()->getType();
2690  if (!((SrcType->isAnyPointerType() && DestType->isAnyPointerType()) ||
2691  DestType->isLValueReferenceType()))
2692  return;
2693 
2694  QualType TheOffendingSrcType, TheOffendingDestType;
2695  Qualifiers CastAwayQualifiers;
2696  if (CastsAwayConstness(Self, SrcType, DestType, true, false,
2697  &TheOffendingSrcType, &TheOffendingDestType,
2698  &CastAwayQualifiers) !=
2699  CastAwayConstnessKind::CACK_Similar)
2700  return;
2701 
2702  // FIXME: 'restrict' is not properly handled here.
2703  int qualifiers = -1;
2704  if (CastAwayQualifiers.hasConst() && CastAwayQualifiers.hasVolatile()) {
2705  qualifiers = 0;
2706  } else if (CastAwayQualifiers.hasConst()) {
2707  qualifiers = 1;
2708  } else if (CastAwayQualifiers.hasVolatile()) {
2709  qualifiers = 2;
2710  }
2711  // This is a variant of int **x; const int **y = (const int **)x;
2712  if (qualifiers == -1)
2713  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual2)
2714  << SrcType << DestType;
2715  else
2716  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual)
2717  << TheOffendingSrcType << TheOffendingDestType << qualifiers;
2718 }
2719 
2721  TypeSourceInfo *CastTypeInfo,
2722  SourceLocation RPLoc,
2723  Expr *CastExpr) {
2724  CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
2725  Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2726  Op.OpRange = SourceRange(LPLoc, CastExpr->getEndLoc());
2727 
2728  if (getLangOpts().CPlusPlus) {
2729  Op.CheckCXXCStyleCast(/*FunctionalStyle=*/ false,
2730  isa<InitListExpr>(CastExpr));
2731  } else {
2732  Op.CheckCStyleCast();
2733  }
2734 
2735  if (Op.SrcExpr.isInvalid())
2736  return ExprError();
2737 
2738  // -Wcast-qual
2739  DiagnoseCastQual(Op.Self, Op.SrcExpr, Op.DestType);
2740 
2741  return Op.complete(CStyleCastExpr::Create(Context, Op.ResultType,
2742  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
2743  &Op.BasePath, CastTypeInfo, LPLoc, RPLoc));
2744 }
2745 
2747  QualType Type,
2748  SourceLocation LPLoc,
2749  Expr *CastExpr,
2750  SourceLocation RPLoc) {
2751  assert(LPLoc.isValid() && "List-initialization shouldn't get here.");
2752  CastOperation Op(*this, Type, CastExpr);
2753  Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2754  Op.OpRange = SourceRange(Op.DestRange.getBegin(), CastExpr->getEndLoc());
2755 
2756  Op.CheckCXXCStyleCast(/*FunctionalStyle=*/true, /*ListInit=*/false);
2757  if (Op.SrcExpr.isInvalid())
2758  return ExprError();
2759 
2760  auto *SubExpr = Op.SrcExpr.get();
2761  if (auto *BindExpr = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
2762  SubExpr = BindExpr->getSubExpr();
2763  if (auto *ConstructExpr = dyn_cast<CXXConstructExpr>(SubExpr))
2764  ConstructExpr->setParenOrBraceRange(SourceRange(LPLoc, RPLoc));
2765 
2766  return Op.complete(CXXFunctionalCastExpr::Create(Context, Op.ResultType,
2767  Op.ValueKind, CastTypeInfo, Op.Kind,
2768  Op.SrcExpr.get(), &Op.BasePath, LPLoc, RPLoc));
2769 }
Defines the clang::ASTContext interface.
bool RequireNonAbstractType(SourceLocation Loc, QualType T, TypeDiagnoser &Diagnoser)
Represents a function declaration or definition.
Definition: Decl.h:1717
static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType)
Definition: SemaCast.cpp:1047
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:2511
QualType getPointeeType() const
Definition: Type.h:2524
A (possibly-)qualified type.
Definition: Type.h:642
bool isBlockPointerType() const
Definition: Type.h:6185
bool isMemberPointerType() const
Definition: Type.h:6208
IdentifierInfo * getIdentifierInfo(StringRef Name) const
Return information about the specified preprocessor identifier token.
A cast other than a C-style cast.
Definition: Sema.h:9301
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:1944
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3329
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:1929
bool isRecordType() const
Definition: Type.h:6250
SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID)
Emit a diagnostic.
Definition: Sema.h:1289
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:1061
bool isExtVectorType() const
Definition: Type.h:6266
The cast method is appropriate and successful.
Definition: SemaCast.cpp:35
FailureKind getFailureKind() const
Determine why initialization failed.
CanQualType ARCUnbridgedCastTy
Definition: ASTContext.h:1056
The base class of the type hierarchy.
Definition: Type.h:1415
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:394
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:699
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:3146
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:1876
bool CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, CastKind &Kind)
Definition: SemaExpr.cpp:6059
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:1748
void removeObjCLifetime()
Definition: Type.h:336
DiagnosticsEngine & Diags
Definition: Sema.h:321
bool isEnumeralType() const
Definition: Type.h:6254
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:1839
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6590
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:2688
bool isInvalidDecl() const
Definition: DeclBase.h:547
OpenCLOptions & getOpenCLOptions()
Definition: Sema.h:1213
Defines the clang::Expr interface and subclasses for C++ expressions.
The collection of all-type qualifiers we support.
Definition: Type.h:141
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:1018
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:154
bool allowsNonTrivialObjCLifetimeQualifiers() const
True if any ObjC types may have non-trivial lifetime qualifiers.
Definition: LangOptions.h:261
bool isObjCLifetimeType() const
Returns true if objects of this type have lifetime semantics under ARC.
Definition: Type.cpp:3899
The cast method is not applicable.
Definition: SemaCast.cpp:34
A C-style cast.
Definition: Sema.h:9297
RecordDecl * getDefinition() const
Returns the RecordDecl that actually defines this struct/union/class.
Definition: Decl.h:3751
bool IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base)
Determine whether the type Derived is a C++ class that is derived from the type Base.
SourceLocation getBeginLoc() const LLVM_READONLY
Definition: Stmt.cpp:280
TryCastResult
Definition: SemaCast.cpp:33
static TryCastResult getCastAwayConstnessCastKind(CastAwayConstnessKind CACK, unsigned &DiagID)
Definition: SemaCast.cpp:652
void removeConst()
Definition: Type.h:262
bool isReferenceType() const
Definition: Type.h:6189
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:9673
Expr * getSubExpr()
Definition: Expr.h:2855
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:6107
bool isIntegralOrEnumerationType() const
Determine whether this type is an integral or enumeration type.
Definition: Type.h:6504
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:2426
bool isGLValue() const
Definition: Expr.h:251
static bool isValidCast(TryCastResult TCR)
Definition: SemaCast.cpp:42
bool isCompleteType(SourceLocation Loc, QualType T)
Definition: Sema.h:1622
An rvalue reference type, per C++11 [dcl.ref].
Definition: Type.h:2712
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:9679
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:404
const Type * getClass() const
Definition: Type.h:2764
bool isRValueReferenceType() const
Definition: Type.h:6197
CheckedConversionKind
The kind of conversion being performed.
Definition: Sema.h:9293
static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, bool CStyle, SourceRange OpRange, unsigned &msg, CastKind &Kind)
Definition: SemaCast.cpp:1980
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:7213
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:5953
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:2790
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:2684
const internal::VariadicDynCastAllOfMatcher< Stmt, CastExpr > castExpr
Matches any cast nodes of Clang&#39;s AST.
const LangOptions & getLangOpts() const
Definition: Sema.h:1212
ExprResult DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose=true)
Definition: SemaExpr.cpp:630
bool isScalarType() const
Definition: Type.h:6489
bool compatiblyIncludesObjCLifetime(Qualifiers other) const
Determines if these qualifiers compatibly include another set of qualifiers from the narrow perspecti...
Definition: Type.h:507
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:5832
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:258
bool isHalfType() const
Definition: Type.h:6410
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:1605
A functional-style cast.
Definition: Sema.h:9299
bool compatiblyIncludes(Qualifiers other) const
Determines if these qualifiers compatibly include another set.
Definition: Type.h:486
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:1667
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:6335
This represents one expression.
Definition: Expr.h:105
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:2668
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:2645
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:1590
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6653
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:6429
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:769
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:16355
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:1612
bool isConstructorInitialization() const
Determine whether this initialization is direct call to a constructor.
Definition: SemaInit.cpp:3306
ReferenceCompareResult
ReferenceCompareResult - Expresses the result of comparing two types (cv1 T1 and cv2 T2) to determine...
Definition: Sema.h:9670
bool RequireCompleteType(SourceLocation Loc, QualType T, TypeDiagnoser &Diagnoser)
Ensure that the type T is a complete type.
Definition: SemaType.cpp:7535
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:1836
QualType getType() const
Definition: Expr.h:127
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:1494
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:1218
Represents a GCC generic vector type.
Definition: Type.h:3142
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:1310
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:1402
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.
SourceLocation getEndLoc() const LLVM_READONLY
Definition: Stmt.cpp:293
unsigned getCVRQualifiers() const
Retrieve the set of CVR (const-volatile-restrict) qualifiers applied to this type.
Definition: Type.h:5986
ExprResult BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, SourceLocation RParenLoc, Expr *Op)
Definition: SemaCast.cpp:2720
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:6024
RecordDecl * getDecl() const
Definition: Type.h:4263
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:1382
CanQualType OverloadTy
Definition: ASTContext.h:1054
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:2581
ActionResult - This structure is used while parsing/acting on expressions, stmts, etc...
Definition: Ownership.h:157
ASTContext & getASTContext() const
Definition: Sema.h:1219
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:4279
CastKind PrepareCastToObjCObjectPointer(ExprResult &E)
Prepare a conversion of the given expression to an ObjC object pointer type.
Definition: SemaExpr.cpp:5817
LangAS getAddressSpace() const
Return the address space of this type.
Definition: Type.h:6069
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:1348
static const FieldDecl * getTargetFieldForToUnionCast(QualType unionType, QualType opType)
Definition: Expr.cpp:1765
bool isIntegralType(const ASTContext &Ctx) const
Determine whether this type is an integral type.
Definition: Type.cpp:1751
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2043
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:6212
bool isObjCObjectPointerType() const
Definition: Type.h:6274
bool isAnyPointerType() const
Definition: Type.h:6181
ImplicitCastExpr - Allows us to explicitly represent implicit type conversions, which have no direct ...
Definition: Expr.h:2924
bool isLValue() const
isLValue - True if this expression is an "l-value" according to the rules of the current language...
Definition: Expr.h:248
Overloading for initialization by constructor failed.
is AltiVec vector
Definition: Type.h:3149
Requests that all candidates be shown.
Definition: Overload.h:69
bool isAddressSpaceOverlapping(const PointerType &other) const
Returns true if address spaces of pointers overlap.
Definition: Type.h:2534
bool isAnyCharacterType() const
Determine whether this type is any of the built-in character types.
Definition: Type.cpp:1815
bool isVectorType() const
Definition: Type.h:6262
void removeObjCGCAttr()
Definition: Type.h:313
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:2299
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:16263
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:6378
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:1770
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:975
const CXXRecordDecl * getParent() const
Returns the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2163
bool isBooleanType() const
Definition: Type.h:6517
ExprResult prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr)
Prepare SplattedExpr for a vector splat operation, adding implicit casts if necessary.
Definition: SemaExpr.cpp:6079
static void checkIntToPointerCast(bool CStyle, SourceLocation Loc, const Expr *SrcExpr, QualType DestType, Sema &Self)
Definition: SemaCast.cpp:1927
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:2730
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:1820
static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType, ExprResult &Result)
Definition: SemaCast.cpp:1953
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:151
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of structs/unions/cl...
Definition: Type.h:4253
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:6438
ExprResult CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *CastExpr, CastKind &Kind)
Definition: SemaExpr.cpp:6112
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:6173
MaterializeTemporaryExpr * CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary, bool BoundToLvalueReference)
Definition: SemaInit.cpp:7179
CXXBasePath & front()
Base for LValueReferenceType and RValueReferenceType.
Definition: Type.h:2647
bool hasSameType(QualType T1, QualType T2) const
Determine whether the given types T1 and T2 are equivalent.
Definition: ASTContext.h:2275
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:1252
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:2793
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:2076
bool isObjCObjectType() const
Definition: Type.h:6278
QualType withCVRQualifiers(unsigned CVR) const
Definition: Type.h:834
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
Definition: ASTContext.h:2259
bool isLValueReferenceType() const
Definition: Type.h:6193
ExprResult BuildCXXFunctionalCastExpr(TypeSourceInfo *TInfo, QualType Type, SourceLocation LParenLoc, Expr *CastExpr, SourceLocation RParenLoc)
Definition: SemaCast.cpp:2746
TypeLoc getTypeLoc() const
Return the TypeLoc wrapper for the type source info.
Definition: TypeLoc.h:238
bool Failed() const
Determine whether the initialization sequence is invalid.
CallingConv getCallConv() const
Definition: Type.h:3493
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:6033
Represents a C++ struct/union/class.
Definition: DeclCXX.h:300
bool isMemberFunctionPointer() const
Returns true if the member type (i.e.
Definition: Type.h:2754
bool isVoidType() const
Definition: Type.h:6404
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:5980
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:2368
SourceRange getSourceRange() const LLVM_READONLY
SourceLocation tokens are not useful in isolation - they are low level value objects created/interpre...
Definition: Stmt.cpp:268
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:280
ExprResult ExprError()
Definition: Ownership.h:283
static Qualifiers fromCVRMask(unsigned CVR)
Definition: Type.h:234
bool hasVolatile() const
Definition: Type.h:265
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:2417
bool isDependentType() const
Whether this type is a dependent type, meaning that its definition somehow depends on a template para...
Definition: Type.h:2056
A reference to a declared variable, function, enum, etc.
Definition: Expr.h:971
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:3229
NestedNameSpecifierLoc getQualifierLoc() const
Fetches the nested-name qualifier with source-location information, if one was given.
Definition: ExprCXX.h:2700
bool isPointerType() const
Definition: Type.h:6177
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:2809
bool isFloatingType() const
Definition: Type.cpp:1913
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:6201
SourceLocation getBegin() const
const LangOptions & getLangOpts() const
Definition: ASTContext.h:716
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:1846
CastType
Definition: SemaCast.cpp:46
QualType getPointeeType() const
Definition: Type.h:2750
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