clang  9.0.0svn
SemaCast.cpp
Go to the documentation of this file.
1 //===--- SemaCast.cpp - Semantic Analysis for Casts -----------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements semantic analysis for cast expressions, including
10 // 1) C-style casts like '(int) x'
11 // 2) C++ functional casts like 'int(x)'
12 // 3) C++ named casts like 'static_cast<int>(x)'
13 //
14 //===----------------------------------------------------------------------===//
15 
17 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/ExprCXX.h"
20 #include "clang/AST/ExprObjC.h"
21 #include "clang/AST/RecordLayout.h"
23 #include "clang/Basic/TargetInfo.h"
24 #include "clang/Lex/Preprocessor.h"
26 #include "llvm/ADT/SmallVector.h"
27 #include <set>
28 using namespace clang;
29 
30 
31 
33  TC_NotApplicable, ///< The cast method is not applicable.
34  TC_Success, ///< The cast method is appropriate and successful.
35  TC_Extension, ///< The cast method is appropriate and accepted as a
36  ///< language extension.
37  TC_Failed ///< The cast method is appropriate, but failed. A
38  ///< diagnostic has been emitted.
39 };
40 
41 static bool isValidCast(TryCastResult TCR) {
42  return TCR == TC_Success || TCR == TC_Extension;
43 }
44 
45 enum CastType {
46  CT_Const, ///< const_cast
47  CT_Static, ///< static_cast
48  CT_Reinterpret, ///< reinterpret_cast
49  CT_Dynamic, ///< dynamic_cast
50  CT_CStyle, ///< (Type)expr
51  CT_Functional ///< Type(expr)
52 };
53 
54 namespace {
55  struct CastOperation {
56  CastOperation(Sema &S, QualType destType, ExprResult src)
57  : Self(S), SrcExpr(src), DestType(destType),
58  ResultType(destType.getNonLValueExprType(S.Context)),
59  ValueKind(Expr::getValueKindForType(destType)),
60  Kind(CK_Dependent), IsARCUnbridgedCast(false) {
61 
62  if (const BuiltinType *placeholder =
63  src.get()->getType()->getAsPlaceholderType()) {
64  PlaceholderKind = placeholder->getKind();
65  } else {
66  PlaceholderKind = (BuiltinType::Kind) 0;
67  }
68  }
69 
70  Sema &Self;
71  ExprResult SrcExpr;
72  QualType DestType;
73  QualType ResultType;
74  ExprValueKind ValueKind;
75  CastKind Kind;
76  BuiltinType::Kind PlaceholderKind;
77  CXXCastPath BasePath;
78  bool IsARCUnbridgedCast;
79 
80  SourceRange OpRange;
81  SourceRange DestRange;
82 
83  // Top-level semantics-checking routines.
84  void CheckConstCast();
85  void CheckReinterpretCast();
86  void CheckStaticCast();
87  void CheckDynamicCast();
88  void CheckCXXCStyleCast(bool FunctionalCast, bool ListInitialization);
89  void CheckCStyleCast();
90 
91  void updatePartOfExplicitCastFlags(CastExpr *CE) {
92  // Walk down from the CE to the OrigSrcExpr, and mark all immediate
93  // ImplicitCastExpr's as being part of ExplicitCastExpr. The original CE
94  // (which is a ExplicitCastExpr), and the OrigSrcExpr are not touched.
95  for (; auto *ICE = dyn_cast<ImplicitCastExpr>(CE->getSubExpr()); CE = ICE)
96  ICE->setIsPartOfExplicitCast(true);
97  }
98 
99  /// Complete an apparently-successful cast operation that yields
100  /// the given expression.
101  ExprResult complete(CastExpr *castExpr) {
102  // If this is an unbridged cast, wrap the result in an implicit
103  // cast that yields the unbridged-cast placeholder type.
104  if (IsARCUnbridgedCast) {
105  castExpr = ImplicitCastExpr::Create(Self.Context,
107  CK_Dependent, castExpr, nullptr,
108  castExpr->getValueKind());
109  }
110  updatePartOfExplicitCastFlags(castExpr);
111  return castExpr;
112  }
113 
114  // Internal convenience methods.
115 
116  /// Try to handle the given placeholder expression kind. Return
117  /// true if the source expression has the appropriate placeholder
118  /// kind. A placeholder can only be claimed once.
119  bool claimPlaceholder(BuiltinType::Kind K) {
120  if (PlaceholderKind != K) return false;
121 
122  PlaceholderKind = (BuiltinType::Kind) 0;
123  return true;
124  }
125 
126  bool isPlaceholder() const {
127  return PlaceholderKind != 0;
128  }
129  bool isPlaceholder(BuiltinType::Kind K) const {
130  return PlaceholderKind == K;
131  }
132 
133  // Language specific cast restrictions for address spaces.
134  void checkAddressSpaceCast(QualType SrcType, QualType DestType);
135 
136  void checkCastAlign() {
137  Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange);
138  }
139 
140  void checkObjCConversion(Sema::CheckedConversionKind CCK) {
142 
143  Expr *src = SrcExpr.get();
144  if (Self.CheckObjCConversion(OpRange, DestType, src, CCK) ==
146  IsARCUnbridgedCast = true;
147  SrcExpr = src;
148  }
149 
150  /// Check for and handle non-overload placeholder expressions.
151  void checkNonOverloadPlaceholders() {
152  if (!isPlaceholder() || isPlaceholder(BuiltinType::Overload))
153  return;
154 
155  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
156  if (SrcExpr.isInvalid())
157  return;
158  PlaceholderKind = (BuiltinType::Kind) 0;
159  }
160  };
161 }
162 
163 static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
164  QualType DestType);
165 
166 // The Try functions attempt a specific way of casting. If they succeed, they
167 // return TC_Success. If their way of casting is not appropriate for the given
168 // arguments, they return TC_NotApplicable and *may* set diag to a diagnostic
169 // to emit if no other way succeeds. If their way of casting is appropriate but
170 // fails, they return TC_Failed and *must* set diag; they can set it to 0 if
171 // they emit a specialized diagnostic.
172 // All diagnostics returned by these functions must expect the same three
173 // arguments:
174 // %0: Cast Type (a value from the CastType enumeration)
175 // %1: Source Type
176 // %2: Destination Type
177 static TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
178  QualType DestType, bool CStyle,
179  CastKind &Kind,
180  CXXCastPath &BasePath,
181  unsigned &msg);
182 static TryCastResult TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr,
183  QualType DestType, bool CStyle,
184  SourceRange OpRange,
185  unsigned &msg,
186  CastKind &Kind,
187  CXXCastPath &BasePath);
189  QualType DestType, bool CStyle,
190  SourceRange OpRange,
191  unsigned &msg,
192  CastKind &Kind,
193  CXXCastPath &BasePath);
194 static TryCastResult TryStaticDowncast(Sema &Self, CanQualType SrcType,
195  CanQualType DestType, bool CStyle,
196  SourceRange OpRange,
197  QualType OrigSrcType,
198  QualType OrigDestType, unsigned &msg,
199  CastKind &Kind,
200  CXXCastPath &BasePath);
202  QualType SrcType,
203  QualType DestType,bool CStyle,
204  SourceRange OpRange,
205  unsigned &msg,
206  CastKind &Kind,
207  CXXCastPath &BasePath);
208 
209 static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr,
210  QualType DestType,
212  SourceRange OpRange,
213  unsigned &msg, CastKind &Kind,
214  bool ListInitialization);
215 static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
216  QualType DestType,
218  SourceRange OpRange,
219  unsigned &msg, CastKind &Kind,
220  CXXCastPath &BasePath,
221  bool ListInitialization);
222 static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
223  QualType DestType, bool CStyle,
224  unsigned &msg);
225 static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
226  QualType DestType, bool CStyle,
227  SourceRange OpRange,
228  unsigned &msg,
229  CastKind &Kind);
230 
231 
232 /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
235  SourceLocation LAngleBracketLoc, Declarator &D,
236  SourceLocation RAngleBracketLoc,
237  SourceLocation LParenLoc, Expr *E,
238  SourceLocation RParenLoc) {
239 
240  assert(!D.isInvalidType());
241 
242  TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, E->getType());
243  if (D.isInvalidType())
244  return ExprError();
245 
246  if (getLangOpts().CPlusPlus) {
247  // Check that there are no default arguments (C++ only).
248  CheckExtraCXXDefaultArguments(D);
249  }
250 
251  return BuildCXXNamedCast(OpLoc, Kind, TInfo, E,
252  SourceRange(LAngleBracketLoc, RAngleBracketLoc),
253  SourceRange(LParenLoc, RParenLoc));
254 }
255 
258  TypeSourceInfo *DestTInfo, Expr *E,
259  SourceRange AngleBrackets, SourceRange Parens) {
260  ExprResult Ex = E;
261  QualType DestType = DestTInfo->getType();
262 
263  // If the type is dependent, we won't do the semantic analysis now.
264  bool TypeDependent =
265  DestType->isDependentType() || Ex.get()->isTypeDependent();
266 
267  CastOperation Op(*this, DestType, E);
268  Op.OpRange = SourceRange(OpLoc, Parens.getEnd());
269  Op.DestRange = AngleBrackets;
270 
271  switch (Kind) {
272  default: llvm_unreachable("Unknown C++ cast!");
273 
274  case tok::kw_const_cast:
275  if (!TypeDependent) {
276  Op.CheckConstCast();
277  if (Op.SrcExpr.isInvalid())
278  return ExprError();
279  DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
280  }
281  return Op.complete(CXXConstCastExpr::Create(Context, Op.ResultType,
282  Op.ValueKind, Op.SrcExpr.get(), DestTInfo,
283  OpLoc, Parens.getEnd(),
284  AngleBrackets));
285 
286  case tok::kw_dynamic_cast: {
287  // OpenCL C++ 1.0 s2.9: dynamic_cast is not supported.
288  if (getLangOpts().OpenCLCPlusPlus) {
289  return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
290  << "dynamic_cast");
291  }
292 
293  if (!TypeDependent) {
294  Op.CheckDynamicCast();
295  if (Op.SrcExpr.isInvalid())
296  return ExprError();
297  }
298  return Op.complete(CXXDynamicCastExpr::Create(Context, Op.ResultType,
299  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
300  &Op.BasePath, DestTInfo,
301  OpLoc, Parens.getEnd(),
302  AngleBrackets));
303  }
304  case tok::kw_reinterpret_cast: {
305  if (!TypeDependent) {
306  Op.CheckReinterpretCast();
307  if (Op.SrcExpr.isInvalid())
308  return ExprError();
309  DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
310  }
311  return Op.complete(CXXReinterpretCastExpr::Create(Context, Op.ResultType,
312  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
313  nullptr, DestTInfo, OpLoc,
314  Parens.getEnd(),
315  AngleBrackets));
316  }
317  case tok::kw_static_cast: {
318  if (!TypeDependent) {
319  Op.CheckStaticCast();
320  if (Op.SrcExpr.isInvalid())
321  return ExprError();
322  DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
323  }
324 
325  return Op.complete(CXXStaticCastExpr::Create(Context, Op.ResultType,
326  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
327  &Op.BasePath, DestTInfo,
328  OpLoc, Parens.getEnd(),
329  AngleBrackets));
330  }
331  }
332 }
333 
334 /// Try to diagnose a failed overloaded cast. Returns true if
335 /// diagnostics were emitted.
337  SourceRange range, Expr *src,
338  QualType destType,
339  bool listInitialization) {
340  switch (CT) {
341  // These cast kinds don't consider user-defined conversions.
342  case CT_Const:
343  case CT_Reinterpret:
344  case CT_Dynamic:
345  return false;
346 
347  // These do.
348  case CT_Static:
349  case CT_CStyle:
350  case CT_Functional:
351  break;
352  }
353 
354  QualType srcType = src->getType();
355  if (!destType->isRecordType() && !srcType->isRecordType())
356  return false;
357 
359  InitializationKind initKind
361  range, listInitialization)
363  listInitialization)
364  : InitializationKind::CreateCast(/*type range?*/ range);
365  InitializationSequence sequence(S, entity, initKind, src);
366 
367  assert(sequence.Failed() && "initialization succeeded on second try?");
368  switch (sequence.getFailureKind()) {
369  default: return false;
370 
373  break;
374  }
375 
376  OverloadCandidateSet &candidates = sequence.getFailedCandidateSet();
377 
378  unsigned msg = 0;
380 
381  switch (sequence.getFailedOverloadResult()) {
382  case OR_Success: llvm_unreachable("successful failed overload");
384  if (candidates.empty())
385  msg = diag::err_ovl_no_conversion_in_cast;
386  else
387  msg = diag::err_ovl_no_viable_conversion_in_cast;
388  howManyCandidates = OCD_AllCandidates;
389  break;
390 
391  case OR_Ambiguous:
392  msg = diag::err_ovl_ambiguous_conversion_in_cast;
393  howManyCandidates = OCD_ViableCandidates;
394  break;
395 
396  case OR_Deleted:
397  msg = diag::err_ovl_deleted_conversion_in_cast;
398  howManyCandidates = OCD_ViableCandidates;
399  break;
400  }
401 
402  S.Diag(range.getBegin(), msg)
403  << CT << srcType << destType
404  << range << src->getSourceRange();
405 
406  candidates.NoteCandidates(S, howManyCandidates, src);
407 
408  return true;
409 }
410 
411 /// Diagnose a failed cast.
412 static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType,
413  SourceRange opRange, Expr *src, QualType destType,
414  bool listInitialization) {
415  if (msg == diag::err_bad_cxx_cast_generic &&
416  tryDiagnoseOverloadedCast(S, castType, opRange, src, destType,
417  listInitialization))
418  return;
419 
420  S.Diag(opRange.getBegin(), msg) << castType
421  << src->getType() << destType << opRange << src->getSourceRange();
422 
423  // Detect if both types are (ptr to) class, and note any incompleteness.
424  int DifferentPtrness = 0;
425  QualType From = destType;
426  if (auto Ptr = From->getAs<PointerType>()) {
427  From = Ptr->getPointeeType();
428  DifferentPtrness++;
429  }
430  QualType To = src->getType();
431  if (auto Ptr = To->getAs<PointerType>()) {
432  To = Ptr->getPointeeType();
433  DifferentPtrness--;
434  }
435  if (!DifferentPtrness) {
436  auto RecFrom = From->getAs<RecordType>();
437  auto RecTo = To->getAs<RecordType>();
438  if (RecFrom && RecTo) {
439  auto DeclFrom = RecFrom->getAsCXXRecordDecl();
440  if (!DeclFrom->isCompleteDefinition())
441  S.Diag(DeclFrom->getLocation(), diag::note_type_incomplete)
442  << DeclFrom->getDeclName();
443  auto DeclTo = RecTo->getAsCXXRecordDecl();
444  if (!DeclTo->isCompleteDefinition())
445  S.Diag(DeclTo->getLocation(), diag::note_type_incomplete)
446  << DeclTo->getDeclName();
447  }
448  }
449 }
450 
451 namespace {
452 /// The kind of unwrapping we did when determining whether a conversion casts
453 /// away constness.
455  /// The conversion does not cast away constness.
456  CACK_None = 0,
457  /// We unwrapped similar types.
458  CACK_Similar = 1,
459  /// We unwrapped dissimilar types with similar representations (eg, a pointer
460  /// versus an Objective-C object pointer).
461  CACK_SimilarKind = 2,
462  /// We unwrapped representationally-unrelated types, such as a pointer versus
463  /// a pointer-to-member.
464  CACK_Incoherent = 3,
465 };
466 }
467 
468 /// Unwrap one level of types for CastsAwayConstness.
469 ///
470 /// Like Sema::UnwrapSimilarTypes, this removes one level of indirection from
471 /// both types, provided that they're both pointer-like or array-like. Unlike
472 /// the Sema function, doesn't care if the unwrapped pieces are related.
473 ///
474 /// This function may remove additional levels as necessary for correctness:
475 /// the resulting T1 is unwrapped sufficiently that it is never an array type,
476 /// so that its qualifiers can be directly compared to those of T2 (which will
477 /// have the combined set of qualifiers from all indermediate levels of T2),
478 /// as (effectively) required by [expr.const.cast]p7 replacing T1's qualifiers
479 /// with those from T2.
482  enum { None, Ptr, MemPtr, BlockPtr, Array };
483  auto Classify = [](QualType T) {
484  if (T->isAnyPointerType()) return Ptr;
485  if (T->isMemberPointerType()) return MemPtr;
486  if (T->isBlockPointerType()) return BlockPtr;
487  // We somewhat-arbitrarily don't look through VLA types here. This is at
488  // least consistent with the behavior of UnwrapSimilarTypes.
489  if (T->isConstantArrayType() || T->isIncompleteArrayType()) return Array;
490  return None;
491  };
492 
493  auto Unwrap = [&](QualType T) {
494  if (auto *AT = Context.getAsArrayType(T))
495  return AT->getElementType();
496  return T->getPointeeType();
497  };
498 
500 
501  if (T2->isReferenceType()) {
502  // Special case: if the destination type is a reference type, unwrap it as
503  // the first level. (The source will have been an lvalue expression in this
504  // case, so there is no corresponding "reference to" in T1 to remove.) This
505  // simulates removing a "pointer to" from both sides.
506  T2 = T2->getPointeeType();
507  Kind = CastAwayConstnessKind::CACK_Similar;
508  } else if (Context.UnwrapSimilarTypes(T1, T2)) {
509  Kind = CastAwayConstnessKind::CACK_Similar;
510  } else {
511  // Try unwrapping mismatching levels.
512  int T1Class = Classify(T1);
513  if (T1Class == None)
514  return CastAwayConstnessKind::CACK_None;
515 
516  int T2Class = Classify(T2);
517  if (T2Class == None)
518  return CastAwayConstnessKind::CACK_None;
519 
520  T1 = Unwrap(T1);
521  T2 = Unwrap(T2);
522  Kind = T1Class == T2Class ? CastAwayConstnessKind::CACK_SimilarKind
523  : CastAwayConstnessKind::CACK_Incoherent;
524  }
525 
526  // We've unwrapped at least one level. If the resulting T1 is a (possibly
527  // multidimensional) array type, any qualifier on any matching layer of
528  // T2 is considered to correspond to T1. Decompose down to the element
529  // type of T1 so that we can compare properly.
530  while (true) {
531  Context.UnwrapSimilarArrayTypes(T1, T2);
532 
533  if (Classify(T1) != Array)
534  break;
535 
536  auto T2Class = Classify(T2);
537  if (T2Class == None)
538  break;
539 
540  if (T2Class != Array)
541  Kind = CastAwayConstnessKind::CACK_Incoherent;
542  else if (Kind != CastAwayConstnessKind::CACK_Incoherent)
543  Kind = CastAwayConstnessKind::CACK_SimilarKind;
544 
545  T1 = Unwrap(T1);
546  T2 = Unwrap(T2).withCVRQualifiers(T2.getCVRQualifiers());
547  }
548 
549  return Kind;
550 }
551 
552 /// Check if the pointer conversion from SrcType to DestType casts away
553 /// constness as defined in C++ [expr.const.cast]. This is used by the cast
554 /// checkers. Both arguments must denote pointer (possibly to member) types.
555 ///
556 /// \param CheckCVR Whether to check for const/volatile/restrict qualifiers.
557 /// \param CheckObjCLifetime Whether to check Objective-C lifetime qualifiers.
559 CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType,
560  bool CheckCVR, bool CheckObjCLifetime,
561  QualType *TheOffendingSrcType = nullptr,
562  QualType *TheOffendingDestType = nullptr,
563  Qualifiers *CastAwayQualifiers = nullptr) {
564  // If the only checking we care about is for Objective-C lifetime qualifiers,
565  // and we're not in ObjC mode, there's nothing to check.
566  if (!CheckCVR && CheckObjCLifetime && !Self.Context.getLangOpts().ObjC)
567  return CastAwayConstnessKind::CACK_None;
568 
569  if (!DestType->isReferenceType()) {
570  assert((SrcType->isAnyPointerType() || SrcType->isMemberPointerType() ||
571  SrcType->isBlockPointerType()) &&
572  "Source type is not pointer or pointer to member.");
573  assert((DestType->isAnyPointerType() || DestType->isMemberPointerType() ||
574  DestType->isBlockPointerType()) &&
575  "Destination type is not pointer or pointer to member.");
576  }
577 
578  QualType UnwrappedSrcType = Self.Context.getCanonicalType(SrcType),
579  UnwrappedDestType = Self.Context.getCanonicalType(DestType);
580 
581  // Find the qualifiers. We only care about cvr-qualifiers for the
582  // purpose of this check, because other qualifiers (address spaces,
583  // Objective-C GC, etc.) are part of the type's identity.
584  QualType PrevUnwrappedSrcType = UnwrappedSrcType;
585  QualType PrevUnwrappedDestType = UnwrappedDestType;
586  auto WorstKind = CastAwayConstnessKind::CACK_Similar;
587  bool AllConstSoFar = true;
588  while (auto Kind = unwrapCastAwayConstnessLevel(
589  Self.Context, UnwrappedSrcType, UnwrappedDestType)) {
590  // Track the worst kind of unwrap we needed to do before we found a
591  // problem.
592  if (Kind > WorstKind)
593  WorstKind = Kind;
594 
595  // Determine the relevant qualifiers at this level.
596  Qualifiers SrcQuals, DestQuals;
597  Self.Context.getUnqualifiedArrayType(UnwrappedSrcType, SrcQuals);
598  Self.Context.getUnqualifiedArrayType(UnwrappedDestType, DestQuals);
599 
600  // We do not meaningfully track object const-ness of Objective-C object
601  // types. Remove const from the source type if either the source or
602  // the destination is an Objective-C object type.
603  if (UnwrappedSrcType->isObjCObjectType() ||
604  UnwrappedDestType->isObjCObjectType())
605  SrcQuals.removeConst();
606 
607  if (CheckCVR) {
608  Qualifiers SrcCvrQuals =
610  Qualifiers DestCvrQuals =
612 
613  if (SrcCvrQuals != DestCvrQuals) {
614  if (CastAwayQualifiers)
615  *CastAwayQualifiers = SrcCvrQuals - DestCvrQuals;
616 
617  // If we removed a cvr-qualifier, this is casting away 'constness'.
618  if (!DestCvrQuals.compatiblyIncludes(SrcCvrQuals)) {
619  if (TheOffendingSrcType)
620  *TheOffendingSrcType = PrevUnwrappedSrcType;
621  if (TheOffendingDestType)
622  *TheOffendingDestType = PrevUnwrappedDestType;
623  return WorstKind;
624  }
625 
626  // If any prior level was not 'const', this is also casting away
627  // 'constness'. We noted the outermost type missing a 'const' already.
628  if (!AllConstSoFar)
629  return WorstKind;
630  }
631  }
632 
633  if (CheckObjCLifetime &&
634  !DestQuals.compatiblyIncludesObjCLifetime(SrcQuals))
635  return WorstKind;
636 
637  // If we found our first non-const-qualified type, this may be the place
638  // where things start to go wrong.
639  if (AllConstSoFar && !DestQuals.hasConst()) {
640  AllConstSoFar = false;
641  if (TheOffendingSrcType)
642  *TheOffendingSrcType = PrevUnwrappedSrcType;
643  if (TheOffendingDestType)
644  *TheOffendingDestType = PrevUnwrappedDestType;
645  }
646 
647  PrevUnwrappedSrcType = UnwrappedSrcType;
648  PrevUnwrappedDestType = UnwrappedDestType;
649  }
650 
651  return CastAwayConstnessKind::CACK_None;
652 }
653 
655  unsigned &DiagID) {
656  switch (CACK) {
657  case CastAwayConstnessKind::CACK_None:
658  llvm_unreachable("did not cast away constness");
659 
660  case CastAwayConstnessKind::CACK_Similar:
661  // FIXME: Accept these as an extension too?
662  case CastAwayConstnessKind::CACK_SimilarKind:
663  DiagID = diag::err_bad_cxx_cast_qualifiers_away;
664  return TC_Failed;
665 
666  case CastAwayConstnessKind::CACK_Incoherent:
667  DiagID = diag::ext_bad_cxx_cast_qualifiers_away_incoherent;
668  return TC_Extension;
669  }
670 
671  llvm_unreachable("unexpected cast away constness kind");
672 }
673 
674 /// CheckDynamicCast - Check that a dynamic_cast<DestType>(SrcExpr) is valid.
675 /// Refer to C++ 5.2.7 for details. Dynamic casts are used mostly for runtime-
676 /// checked downcasts in class hierarchies.
677 void CastOperation::CheckDynamicCast() {
678  if (ValueKind == VK_RValue)
679  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
680  else if (isPlaceholder())
681  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
682  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
683  return;
684 
685  QualType OrigSrcType = SrcExpr.get()->getType();
686  QualType DestType = Self.Context.getCanonicalType(this->DestType);
687 
688  // C++ 5.2.7p1: T shall be a pointer or reference to a complete class type,
689  // or "pointer to cv void".
690 
691  QualType DestPointee;
692  const PointerType *DestPointer = DestType->getAs<PointerType>();
693  const ReferenceType *DestReference = nullptr;
694  if (DestPointer) {
695  DestPointee = DestPointer->getPointeeType();
696  } else if ((DestReference = DestType->getAs<ReferenceType>())) {
697  DestPointee = DestReference->getPointeeType();
698  } else {
699  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ref_or_ptr)
700  << this->DestType << DestRange;
701  SrcExpr = ExprError();
702  return;
703  }
704 
705  const RecordType *DestRecord = DestPointee->getAs<RecordType>();
706  if (DestPointee->isVoidType()) {
707  assert(DestPointer && "Reference to void is not possible");
708  } else if (DestRecord) {
709  if (Self.RequireCompleteType(OpRange.getBegin(), DestPointee,
710  diag::err_bad_dynamic_cast_incomplete,
711  DestRange)) {
712  SrcExpr = ExprError();
713  return;
714  }
715  } else {
716  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
717  << DestPointee.getUnqualifiedType() << DestRange;
718  SrcExpr = ExprError();
719  return;
720  }
721 
722  // C++0x 5.2.7p2: If T is a pointer type, v shall be an rvalue of a pointer to
723  // complete class type, [...]. If T is an lvalue reference type, v shall be
724  // an lvalue of a complete class type, [...]. If T is an rvalue reference
725  // type, v shall be an expression having a complete class type, [...]
726  QualType SrcType = Self.Context.getCanonicalType(OrigSrcType);
727  QualType SrcPointee;
728  if (DestPointer) {
729  if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
730  SrcPointee = SrcPointer->getPointeeType();
731  } else {
732  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ptr)
733  << OrigSrcType << SrcExpr.get()->getSourceRange();
734  SrcExpr = ExprError();
735  return;
736  }
737  } else if (DestReference->isLValueReferenceType()) {
738  if (!SrcExpr.get()->isLValue()) {
739  Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
740  << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
741  }
742  SrcPointee = SrcType;
743  } else {
744  // If we're dynamic_casting from a prvalue to an rvalue reference, we need
745  // to materialize the prvalue before we bind the reference to it.
746  if (SrcExpr.get()->isRValue())
747  SrcExpr = Self.CreateMaterializeTemporaryExpr(
748  SrcType, SrcExpr.get(), /*IsLValueReference*/ false);
749  SrcPointee = SrcType;
750  }
751 
752  const RecordType *SrcRecord = SrcPointee->getAs<RecordType>();
753  if (SrcRecord) {
754  if (Self.RequireCompleteType(OpRange.getBegin(), SrcPointee,
755  diag::err_bad_dynamic_cast_incomplete,
756  SrcExpr.get())) {
757  SrcExpr = ExprError();
758  return;
759  }
760  } else {
761  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
762  << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
763  SrcExpr = ExprError();
764  return;
765  }
766 
767  assert((DestPointer || DestReference) &&
768  "Bad destination non-ptr/ref slipped through.");
769  assert((DestRecord || DestPointee->isVoidType()) &&
770  "Bad destination pointee slipped through.");
771  assert(SrcRecord && "Bad source pointee slipped through.");
772 
773  // C++ 5.2.7p1: The dynamic_cast operator shall not cast away constness.
774  if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
775  Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_qualifiers_away)
776  << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
777  SrcExpr = ExprError();
778  return;
779  }
780 
781  // C++ 5.2.7p3: If the type of v is the same as the required result type,
782  // [except for cv].
783  if (DestRecord == SrcRecord) {
784  Kind = CK_NoOp;
785  return;
786  }
787 
788  // C++ 5.2.7p5
789  // Upcasts are resolved statically.
790  if (DestRecord &&
791  Self.IsDerivedFrom(OpRange.getBegin(), SrcPointee, DestPointee)) {
792  if (Self.CheckDerivedToBaseConversion(SrcPointee, DestPointee,
793  OpRange.getBegin(), OpRange,
794  &BasePath)) {
795  SrcExpr = ExprError();
796  return;
797  }
798 
799  Kind = CK_DerivedToBase;
800  return;
801  }
802 
803  // C++ 5.2.7p6: Otherwise, v shall be [polymorphic].
804  const RecordDecl *SrcDecl = SrcRecord->getDecl()->getDefinition();
805  assert(SrcDecl && "Definition missing");
806  if (!cast<CXXRecordDecl>(SrcDecl)->isPolymorphic()) {
807  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_polymorphic)
808  << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
809  SrcExpr = ExprError();
810  }
811 
812  // dynamic_cast is not available with -fno-rtti.
813  // As an exception, dynamic_cast to void* is available because it doesn't
814  // use RTTI.
815  if (!Self.getLangOpts().RTTI && !DestPointee->isVoidType()) {
816  Self.Diag(OpRange.getBegin(), diag::err_no_dynamic_cast_with_fno_rtti);
817  SrcExpr = ExprError();
818  return;
819  }
820 
821  // Done. Everything else is run-time checks.
822  Kind = CK_Dynamic;
823 }
824 
825 /// CheckConstCast - Check that a const_cast<DestType>(SrcExpr) is valid.
826 /// Refer to C++ 5.2.11 for details. const_cast is typically used in code
827 /// like this:
828 /// const char *str = "literal";
829 /// legacy_function(const_cast<char*>(str));
830 void CastOperation::CheckConstCast() {
831  if (ValueKind == VK_RValue)
832  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
833  else if (isPlaceholder())
834  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
835  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
836  return;
837 
838  unsigned msg = diag::err_bad_cxx_cast_generic;
839  auto TCR = TryConstCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg);
840  if (TCR != TC_Success && msg != 0) {
841  Self.Diag(OpRange.getBegin(), msg) << CT_Const
842  << SrcExpr.get()->getType() << DestType << OpRange;
843  }
844  if (!isValidCast(TCR))
845  SrcExpr = ExprError();
846 }
847 
848 /// Check that a reinterpret_cast<DestType>(SrcExpr) is not used as upcast
849 /// or downcast between respective pointers or references.
850 static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
851  QualType DestType,
852  SourceRange OpRange) {
853  QualType SrcType = SrcExpr->getType();
854  // When casting from pointer or reference, get pointee type; use original
855  // type otherwise.
856  const CXXRecordDecl *SrcPointeeRD = SrcType->getPointeeCXXRecordDecl();
857  const CXXRecordDecl *SrcRD =
858  SrcPointeeRD ? SrcPointeeRD : SrcType->getAsCXXRecordDecl();
859 
860  // Examining subobjects for records is only possible if the complete and
861  // valid definition is available. Also, template instantiation is not
862  // allowed here.
863  if (!SrcRD || !SrcRD->isCompleteDefinition() || SrcRD->isInvalidDecl())
864  return;
865 
866  const CXXRecordDecl *DestRD = DestType->getPointeeCXXRecordDecl();
867 
868  if (!DestRD || !DestRD->isCompleteDefinition() || DestRD->isInvalidDecl())
869  return;
870 
871  enum {
872  ReinterpretUpcast,
873  ReinterpretDowncast
874  } ReinterpretKind;
875 
876  CXXBasePaths BasePaths;
877 
878  if (SrcRD->isDerivedFrom(DestRD, BasePaths))
879  ReinterpretKind = ReinterpretUpcast;
880  else if (DestRD->isDerivedFrom(SrcRD, BasePaths))
881  ReinterpretKind = ReinterpretDowncast;
882  else
883  return;
884 
885  bool VirtualBase = true;
886  bool NonZeroOffset = false;
887  for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(),
888  E = BasePaths.end();
889  I != E; ++I) {
890  const CXXBasePath &Path = *I;
892  bool IsVirtual = false;
893  for (CXXBasePath::const_iterator IElem = Path.begin(), EElem = Path.end();
894  IElem != EElem; ++IElem) {
895  IsVirtual = IElem->Base->isVirtual();
896  if (IsVirtual)
897  break;
898  const CXXRecordDecl *BaseRD = IElem->Base->getType()->getAsCXXRecordDecl();
899  assert(BaseRD && "Base type should be a valid unqualified class type");
900  // Don't check if any base has invalid declaration or has no definition
901  // since it has no layout info.
902  const CXXRecordDecl *Class = IElem->Class,
903  *ClassDefinition = Class->getDefinition();
904  if (Class->isInvalidDecl() || !ClassDefinition ||
905  !ClassDefinition->isCompleteDefinition())
906  return;
907 
908  const ASTRecordLayout &DerivedLayout =
909  Self.Context.getASTRecordLayout(Class);
910  Offset += DerivedLayout.getBaseClassOffset(BaseRD);
911  }
912  if (!IsVirtual) {
913  // Don't warn if any path is a non-virtually derived base at offset zero.
914  if (Offset.isZero())
915  return;
916  // Offset makes sense only for non-virtual bases.
917  else
918  NonZeroOffset = true;
919  }
920  VirtualBase = VirtualBase && IsVirtual;
921  }
922 
923  (void) NonZeroOffset; // Silence set but not used warning.
924  assert((VirtualBase || NonZeroOffset) &&
925  "Should have returned if has non-virtual base with zero offset");
926 
927  QualType BaseType =
928  ReinterpretKind == ReinterpretUpcast? DestType : SrcType;
929  QualType DerivedType =
930  ReinterpretKind == ReinterpretUpcast? SrcType : DestType;
931 
932  SourceLocation BeginLoc = OpRange.getBegin();
933  Self.Diag(BeginLoc, diag::warn_reinterpret_different_from_static)
934  << DerivedType << BaseType << !VirtualBase << int(ReinterpretKind)
935  << OpRange;
936  Self.Diag(BeginLoc, diag::note_reinterpret_updowncast_use_static)
937  << int(ReinterpretKind)
938  << FixItHint::CreateReplacement(BeginLoc, "static_cast");
939 }
940 
941 /// CheckReinterpretCast - Check that a reinterpret_cast<DestType>(SrcExpr) is
942 /// valid.
943 /// Refer to C++ 5.2.10 for details. reinterpret_cast is typically used in code
944 /// like this:
945 /// char *bytes = reinterpret_cast<char*>(int_ptr);
946 void CastOperation::CheckReinterpretCast() {
947  if (ValueKind == VK_RValue && !isPlaceholder(BuiltinType::Overload))
948  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
949  else
950  checkNonOverloadPlaceholders();
951  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
952  return;
953 
954  unsigned msg = diag::err_bad_cxx_cast_generic;
955  TryCastResult tcr =
956  TryReinterpretCast(Self, SrcExpr, DestType,
957  /*CStyle*/false, OpRange, msg, Kind);
958  if (tcr != TC_Success && msg != 0) {
959  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
960  return;
961  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
962  //FIXME: &f<int>; is overloaded and resolvable
963  Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_overload)
964  << OverloadExpr::find(SrcExpr.get()).Expression->getName()
965  << DestType << OpRange;
966  Self.NoteAllOverloadCandidates(SrcExpr.get());
967 
968  } else {
969  diagnoseBadCast(Self, msg, CT_Reinterpret, OpRange, SrcExpr.get(),
970  DestType, /*listInitialization=*/false);
971  }
972  }
973 
974  if (isValidCast(tcr)) {
976  checkObjCConversion(Sema::CCK_OtherCast);
977  DiagnoseReinterpretUpDownCast(Self, SrcExpr.get(), DestType, OpRange);
978  } else {
979  SrcExpr = ExprError();
980  }
981 }
982 
983 
984 /// CheckStaticCast - Check that a static_cast<DestType>(SrcExpr) is valid.
985 /// Refer to C++ 5.2.9 for details. Static casts are mostly used for making
986 /// implicit conversions explicit and getting rid of data loss warnings.
987 void CastOperation::CheckStaticCast() {
988  if (isPlaceholder()) {
989  checkNonOverloadPlaceholders();
990  if (SrcExpr.isInvalid())
991  return;
992  }
993 
994  // This test is outside everything else because it's the only case where
995  // a non-lvalue-reference target type does not lead to decay.
996  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
997  if (DestType->isVoidType()) {
998  Kind = CK_ToVoid;
999 
1000  if (claimPlaceholder(BuiltinType::Overload)) {
1002  false, // Decay Function to ptr
1003  true, // Complain
1004  OpRange, DestType, diag::err_bad_static_cast_overload);
1005  if (SrcExpr.isInvalid())
1006  return;
1007  }
1008 
1009  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
1010  return;
1011  }
1012 
1013  if (ValueKind == VK_RValue && !DestType->isRecordType() &&
1014  !isPlaceholder(BuiltinType::Overload)) {
1015  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
1016  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
1017  return;
1018  }
1019 
1020  unsigned msg = diag::err_bad_cxx_cast_generic;
1021  TryCastResult tcr
1022  = TryStaticCast(Self, SrcExpr, DestType, Sema::CCK_OtherCast, OpRange, msg,
1023  Kind, BasePath, /*ListInitialization=*/false);
1024  if (tcr != TC_Success && msg != 0) {
1025  if (SrcExpr.isInvalid())
1026  return;
1027  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1028  OverloadExpr* oe = OverloadExpr::find(SrcExpr.get()).Expression;
1029  Self.Diag(OpRange.getBegin(), diag::err_bad_static_cast_overload)
1030  << oe->getName() << DestType << OpRange
1031  << oe->getQualifierLoc().getSourceRange();
1032  Self.NoteAllOverloadCandidates(SrcExpr.get());
1033  } else {
1034  diagnoseBadCast(Self, msg, CT_Static, OpRange, SrcExpr.get(), DestType,
1035  /*listInitialization=*/false);
1036  }
1037  }
1038 
1039  if (isValidCast(tcr)) {
1040  if (Kind == CK_BitCast)
1041  checkCastAlign();
1043  checkObjCConversion(Sema::CCK_OtherCast);
1044  } else {
1045  SrcExpr = ExprError();
1046  }
1047 }
1048 
1049 static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType) {
1050  auto *SrcPtrType = SrcType->getAs<PointerType>();
1051  if (!SrcPtrType)
1052  return false;
1053  auto *DestPtrType = DestType->getAs<PointerType>();
1054  if (!DestPtrType)
1055  return false;
1056  return SrcPtrType->getPointeeType().getAddressSpace() !=
1057  DestPtrType->getPointeeType().getAddressSpace();
1058 }
1059 
1060 /// TryStaticCast - Check if a static cast can be performed, and do so if
1061 /// possible. If @p CStyle, ignore access restrictions on hierarchy casting
1062 /// and casting away constness.
1064  QualType DestType,
1066  SourceRange OpRange, unsigned &msg,
1067  CastKind &Kind, CXXCastPath &BasePath,
1068  bool ListInitialization) {
1069  // Determine whether we have the semantics of a C-style cast.
1070  bool CStyle
1071  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1072 
1073  // The order the tests is not entirely arbitrary. There is one conversion
1074  // that can be handled in two different ways. Given:
1075  // struct A {};
1076  // struct B : public A {
1077  // B(); B(const A&);
1078  // };
1079  // const A &a = B();
1080  // the cast static_cast<const B&>(a) could be seen as either a static
1081  // reference downcast, or an explicit invocation of the user-defined
1082  // conversion using B's conversion constructor.
1083  // DR 427 specifies that the downcast is to be applied here.
1084 
1085  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
1086  // Done outside this function.
1087 
1088  TryCastResult tcr;
1089 
1090  // C++ 5.2.9p5, reference downcast.
1091  // See the function for details.
1092  // DR 427 specifies that this is to be applied before paragraph 2.
1093  tcr = TryStaticReferenceDowncast(Self, SrcExpr.get(), DestType, CStyle,
1094  OpRange, msg, Kind, BasePath);
1095  if (tcr != TC_NotApplicable)
1096  return tcr;
1097 
1098  // C++11 [expr.static.cast]p3:
1099  // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to cv2
1100  // T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1101  tcr = TryLValueToRValueCast(Self, SrcExpr.get(), DestType, CStyle, Kind,
1102  BasePath, msg);
1103  if (tcr != TC_NotApplicable)
1104  return tcr;
1105 
1106  // C++ 5.2.9p2: An expression e can be explicitly converted to a type T
1107  // [...] if the declaration "T t(e);" is well-formed, [...].
1108  tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg,
1109  Kind, ListInitialization);
1110  if (SrcExpr.isInvalid())
1111  return TC_Failed;
1112  if (tcr != TC_NotApplicable)
1113  return tcr;
1114 
1115  // C++ 5.2.9p6: May apply the reverse of any standard conversion, except
1116  // lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
1117  // conversions, subject to further restrictions.
1118  // Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
1119  // of qualification conversions impossible.
1120  // In the CStyle case, the earlier attempt to const_cast should have taken
1121  // care of reverse qualification conversions.
1122 
1123  QualType SrcType = Self.Context.getCanonicalType(SrcExpr.get()->getType());
1124 
1125  // C++0x 5.2.9p9: A value of a scoped enumeration type can be explicitly
1126  // converted to an integral type. [...] A value of a scoped enumeration type
1127  // can also be explicitly converted to a floating-point type [...].
1128  if (const EnumType *Enum = SrcType->getAs<EnumType>()) {
1129  if (Enum->getDecl()->isScoped()) {
1130  if (DestType->isBooleanType()) {
1131  Kind = CK_IntegralToBoolean;
1132  return TC_Success;
1133  } else if (DestType->isIntegralType(Self.Context)) {
1134  Kind = CK_IntegralCast;
1135  return TC_Success;
1136  } else if (DestType->isRealFloatingType()) {
1137  Kind = CK_IntegralToFloating;
1138  return TC_Success;
1139  }
1140  }
1141  }
1142 
1143  // Reverse integral promotion/conversion. All such conversions are themselves
1144  // again integral promotions or conversions and are thus already handled by
1145  // p2 (TryDirectInitialization above).
1146  // (Note: any data loss warnings should be suppressed.)
1147  // The exception is the reverse of enum->integer, i.e. integer->enum (and
1148  // enum->enum). See also C++ 5.2.9p7.
1149  // The same goes for reverse floating point promotion/conversion and
1150  // floating-integral conversions. Again, only floating->enum is relevant.
1151  if (DestType->isEnumeralType()) {
1152  if (SrcType->isIntegralOrEnumerationType()) {
1153  Kind = CK_IntegralCast;
1154  return TC_Success;
1155  } else if (SrcType->isRealFloatingType()) {
1156  Kind = CK_FloatingToIntegral;
1157  return TC_Success;
1158  }
1159  }
1160 
1161  // Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
1162  // C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
1163  tcr = TryStaticPointerDowncast(Self, SrcType, DestType, CStyle, OpRange, msg,
1164  Kind, BasePath);
1165  if (tcr != TC_NotApplicable)
1166  return tcr;
1167 
1168  // Reverse member pointer conversion. C++ 4.11 specifies member pointer
1169  // conversion. C++ 5.2.9p9 has additional information.
1170  // DR54's access restrictions apply here also.
1171  tcr = TryStaticMemberPointerUpcast(Self, SrcExpr, SrcType, DestType, CStyle,
1172  OpRange, msg, Kind, BasePath);
1173  if (tcr != TC_NotApplicable)
1174  return tcr;
1175 
1176  // Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
1177  // void*. C++ 5.2.9p10 specifies additional restrictions, which really is
1178  // just the usual constness stuff.
1179  if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
1180  QualType SrcPointee = SrcPointer->getPointeeType();
1181  if (SrcPointee->isVoidType()) {
1182  if (const PointerType *DestPointer = DestType->getAs<PointerType>()) {
1183  QualType DestPointee = DestPointer->getPointeeType();
1184  if (DestPointee->isIncompleteOrObjectType()) {
1185  // This is definitely the intended conversion, but it might fail due
1186  // to a qualifier violation. Note that we permit Objective-C lifetime
1187  // and GC qualifier mismatches here.
1188  if (!CStyle) {
1189  Qualifiers DestPointeeQuals = DestPointee.getQualifiers();
1190  Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers();
1191  DestPointeeQuals.removeObjCGCAttr();
1192  DestPointeeQuals.removeObjCLifetime();
1193  SrcPointeeQuals.removeObjCGCAttr();
1194  SrcPointeeQuals.removeObjCLifetime();
1195  if (DestPointeeQuals != SrcPointeeQuals &&
1196  !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) {
1197  msg = diag::err_bad_cxx_cast_qualifiers_away;
1198  return TC_Failed;
1199  }
1200  }
1201  Kind = IsAddressSpaceConversion(SrcType, DestType)
1202  ? CK_AddressSpaceConversion
1203  : CK_BitCast;
1204  return TC_Success;
1205  }
1206 
1207  // Microsoft permits static_cast from 'pointer-to-void' to
1208  // 'pointer-to-function'.
1209  if (!CStyle && Self.getLangOpts().MSVCCompat &&
1210  DestPointee->isFunctionType()) {
1211  Self.Diag(OpRange.getBegin(), diag::ext_ms_cast_fn_obj) << OpRange;
1212  Kind = CK_BitCast;
1213  return TC_Success;
1214  }
1215  }
1216  else if (DestType->isObjCObjectPointerType()) {
1217  // allow both c-style cast and static_cast of objective-c pointers as
1218  // they are pervasive.
1219  Kind = CK_CPointerToObjCPointerCast;
1220  return TC_Success;
1221  }
1222  else if (CStyle && DestType->isBlockPointerType()) {
1223  // allow c-style cast of void * to block pointers.
1224  Kind = CK_AnyPointerToBlockPointerCast;
1225  return TC_Success;
1226  }
1227  }
1228  }
1229  // Allow arbitrary objective-c pointer conversion with static casts.
1230  if (SrcType->isObjCObjectPointerType() &&
1231  DestType->isObjCObjectPointerType()) {
1232  Kind = CK_BitCast;
1233  return TC_Success;
1234  }
1235  // Allow ns-pointer to cf-pointer conversion in either direction
1236  // with static casts.
1237  if (!CStyle &&
1238  Self.CheckTollFreeBridgeStaticCast(DestType, SrcExpr.get(), Kind))
1239  return TC_Success;
1240 
1241  // See if it looks like the user is trying to convert between
1242  // related record types, and select a better diagnostic if so.
1243  if (auto SrcPointer = SrcType->getAs<PointerType>())
1244  if (auto DestPointer = DestType->getAs<PointerType>())
1245  if (SrcPointer->getPointeeType()->getAs<RecordType>() &&
1246  DestPointer->getPointeeType()->getAs<RecordType>())
1247  msg = diag::err_bad_cxx_cast_unrelated_class;
1248 
1249  // We tried everything. Everything! Nothing works! :-(
1250  return TC_NotApplicable;
1251 }
1252 
1253 /// Tests whether a conversion according to N2844 is valid.
1255  QualType DestType, bool CStyle,
1256  CastKind &Kind, CXXCastPath &BasePath,
1257  unsigned &msg) {
1258  // C++11 [expr.static.cast]p3:
1259  // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
1260  // cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1261  const RValueReferenceType *R = DestType->getAs<RValueReferenceType>();
1262  if (!R)
1263  return TC_NotApplicable;
1264 
1265  if (!SrcExpr->isGLValue())
1266  return TC_NotApplicable;
1267 
1268  // Because we try the reference downcast before this function, from now on
1269  // this is the only cast possibility, so we issue an error if we fail now.
1270  // FIXME: Should allow casting away constness if CStyle.
1271  bool DerivedToBase;
1272  bool ObjCConversion;
1273  bool ObjCLifetimeConversion;
1274  QualType FromType = SrcExpr->getType();
1275  QualType ToType = R->getPointeeType();
1276  if (CStyle) {
1277  FromType = FromType.getUnqualifiedType();
1278  ToType = ToType.getUnqualifiedType();
1279  }
1280 
1282  SrcExpr->getBeginLoc(), ToType, FromType, DerivedToBase, ObjCConversion,
1283  ObjCLifetimeConversion);
1284  if (RefResult != Sema::Ref_Compatible) {
1285  if (CStyle || RefResult == Sema::Ref_Incompatible)
1286  return TC_NotApplicable;
1287  // Diagnose types which are reference-related but not compatible here since
1288  // we can provide better diagnostics. In these cases forwarding to
1289  // [expr.static.cast]p4 should never result in a well-formed cast.
1290  msg = SrcExpr->isLValue() ? diag::err_bad_lvalue_to_rvalue_cast
1291  : diag::err_bad_rvalue_to_rvalue_cast;
1292  return TC_Failed;
1293  }
1294 
1295  if (DerivedToBase) {
1296  Kind = CK_DerivedToBase;
1297  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1298  /*DetectVirtual=*/true);
1299  if (!Self.IsDerivedFrom(SrcExpr->getBeginLoc(), SrcExpr->getType(),
1300  R->getPointeeType(), Paths))
1301  return TC_NotApplicable;
1302 
1303  Self.BuildBasePathArray(Paths, BasePath);
1304  } else
1305  Kind = CK_NoOp;
1306 
1307  return TC_Success;
1308 }
1309 
1310 /// Tests whether a conversion according to C++ 5.2.9p5 is valid.
1312 TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType,
1313  bool CStyle, SourceRange OpRange,
1314  unsigned &msg, CastKind &Kind,
1315  CXXCastPath &BasePath) {
1316  // C++ 5.2.9p5: An lvalue of type "cv1 B", where B is a class type, can be
1317  // cast to type "reference to cv2 D", where D is a class derived from B,
1318  // if a valid standard conversion from "pointer to D" to "pointer to B"
1319  // exists, cv2 >= cv1, and B is not a virtual base class of D.
1320  // In addition, DR54 clarifies that the base must be accessible in the
1321  // current context. Although the wording of DR54 only applies to the pointer
1322  // variant of this rule, the intent is clearly for it to apply to the this
1323  // conversion as well.
1324 
1325  const ReferenceType *DestReference = DestType->getAs<ReferenceType>();
1326  if (!DestReference) {
1327  return TC_NotApplicable;
1328  }
1329  bool RValueRef = DestReference->isRValueReferenceType();
1330  if (!RValueRef && !SrcExpr->isLValue()) {
1331  // We know the left side is an lvalue reference, so we can suggest a reason.
1332  msg = diag::err_bad_cxx_cast_rvalue;
1333  return TC_NotApplicable;
1334  }
1335 
1336  QualType DestPointee = DestReference->getPointeeType();
1337 
1338  // FIXME: If the source is a prvalue, we should issue a warning (because the
1339  // cast always has undefined behavior), and for AST consistency, we should
1340  // materialize a temporary.
1341  return TryStaticDowncast(Self,
1342  Self.Context.getCanonicalType(SrcExpr->getType()),
1343  Self.Context.getCanonicalType(DestPointee), CStyle,
1344  OpRange, SrcExpr->getType(), DestType, msg, Kind,
1345  BasePath);
1346 }
1347 
1348 /// Tests whether a conversion according to C++ 5.2.9p8 is valid.
1351  bool CStyle, SourceRange OpRange,
1352  unsigned &msg, CastKind &Kind,
1353  CXXCastPath &BasePath) {
1354  // C++ 5.2.9p8: An rvalue of type "pointer to cv1 B", where B is a class
1355  // type, can be converted to an rvalue of type "pointer to cv2 D", where D
1356  // is a class derived from B, if a valid standard conversion from "pointer
1357  // to D" to "pointer to B" exists, cv2 >= cv1, and B is not a virtual base
1358  // class of D.
1359  // In addition, DR54 clarifies that the base must be accessible in the
1360  // current context.
1361 
1362  const PointerType *DestPointer = DestType->getAs<PointerType>();
1363  if (!DestPointer) {
1364  return TC_NotApplicable;
1365  }
1366 
1367  const PointerType *SrcPointer = SrcType->getAs<PointerType>();
1368  if (!SrcPointer) {
1369  msg = diag::err_bad_static_cast_pointer_nonpointer;
1370  return TC_NotApplicable;
1371  }
1372 
1373  return TryStaticDowncast(Self,
1374  Self.Context.getCanonicalType(SrcPointer->getPointeeType()),
1375  Self.Context.getCanonicalType(DestPointer->getPointeeType()),
1376  CStyle, OpRange, SrcType, DestType, msg, Kind,
1377  BasePath);
1378 }
1379 
1380 /// TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and
1381 /// TryStaticPointerDowncast. Tests whether a static downcast from SrcType to
1382 /// DestType is possible and allowed.
1385  bool CStyle, SourceRange OpRange, QualType OrigSrcType,
1386  QualType OrigDestType, unsigned &msg,
1387  CastKind &Kind, CXXCastPath &BasePath) {
1388  // We can only work with complete types. But don't complain if it doesn't work
1389  if (!Self.isCompleteType(OpRange.getBegin(), SrcType) ||
1390  !Self.isCompleteType(OpRange.getBegin(), DestType))
1391  return TC_NotApplicable;
1392 
1393  // Downcast can only happen in class hierarchies, so we need classes.
1394  if (!DestType->getAs<RecordType>() || !SrcType->getAs<RecordType>()) {
1395  return TC_NotApplicable;
1396  }
1397 
1398  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1399  /*DetectVirtual=*/true);
1400  if (!Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths)) {
1401  return TC_NotApplicable;
1402  }
1403 
1404  // Target type does derive from source type. Now we're serious. If an error
1405  // appears now, it's not ignored.
1406  // This may not be entirely in line with the standard. Take for example:
1407  // struct A {};
1408  // struct B : virtual A {
1409  // B(A&);
1410  // };
1411  //
1412  // void f()
1413  // {
1414  // (void)static_cast<const B&>(*((A*)0));
1415  // }
1416  // As far as the standard is concerned, p5 does not apply (A is virtual), so
1417  // p2 should be used instead - "const B& t(*((A*)0));" is perfectly valid.
1418  // However, both GCC and Comeau reject this example, and accepting it would
1419  // mean more complex code if we're to preserve the nice error message.
1420  // FIXME: Being 100% compliant here would be nice to have.
1421 
1422  // Must preserve cv, as always, unless we're in C-style mode.
1423  if (!CStyle && !DestType.isAtLeastAsQualifiedAs(SrcType)) {
1424  msg = diag::err_bad_cxx_cast_qualifiers_away;
1425  return TC_Failed;
1426  }
1427 
1428  if (Paths.isAmbiguous(SrcType.getUnqualifiedType())) {
1429  // This code is analoguous to that in CheckDerivedToBaseConversion, except
1430  // that it builds the paths in reverse order.
1431  // To sum up: record all paths to the base and build a nice string from
1432  // them. Use it to spice up the error message.
1433  if (!Paths.isRecordingPaths()) {
1434  Paths.clear();
1435  Paths.setRecordingPaths(true);
1436  Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths);
1437  }
1438  std::string PathDisplayStr;
1439  std::set<unsigned> DisplayedPaths;
1440  for (clang::CXXBasePath &Path : Paths) {
1441  if (DisplayedPaths.insert(Path.back().SubobjectNumber).second) {
1442  // We haven't displayed a path to this particular base
1443  // class subobject yet.
1444  PathDisplayStr += "\n ";
1445  for (CXXBasePathElement &PE : llvm::reverse(Path))
1446  PathDisplayStr += PE.Base->getType().getAsString() + " -> ";
1447  PathDisplayStr += QualType(DestType).getAsString();
1448  }
1449  }
1450 
1451  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_base_to_derived_cast)
1452  << QualType(SrcType).getUnqualifiedType()
1453  << QualType(DestType).getUnqualifiedType()
1454  << PathDisplayStr << OpRange;
1455  msg = 0;
1456  return TC_Failed;
1457  }
1458 
1459  if (Paths.getDetectedVirtual() != nullptr) {
1460  QualType VirtualBase(Paths.getDetectedVirtual(), 0);
1461  Self.Diag(OpRange.getBegin(), diag::err_static_downcast_via_virtual)
1462  << OrigSrcType << OrigDestType << VirtualBase << OpRange;
1463  msg = 0;
1464  return TC_Failed;
1465  }
1466 
1467  if (!CStyle) {
1468  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1469  SrcType, DestType,
1470  Paths.front(),
1471  diag::err_downcast_from_inaccessible_base)) {
1472  case Sema::AR_accessible:
1473  case Sema::AR_delayed: // be optimistic
1474  case Sema::AR_dependent: // be optimistic
1475  break;
1476 
1477  case Sema::AR_inaccessible:
1478  msg = 0;
1479  return TC_Failed;
1480  }
1481  }
1482 
1483  Self.BuildBasePathArray(Paths, BasePath);
1484  Kind = CK_BaseToDerived;
1485  return TC_Success;
1486 }
1487 
1488 /// TryStaticMemberPointerUpcast - Tests whether a conversion according to
1489 /// C++ 5.2.9p9 is valid:
1490 ///
1491 /// An rvalue of type "pointer to member of D of type cv1 T" can be
1492 /// converted to an rvalue of type "pointer to member of B of type cv2 T",
1493 /// where B is a base class of D [...].
1494 ///
1497  QualType DestType, bool CStyle,
1498  SourceRange OpRange,
1499  unsigned &msg, CastKind &Kind,
1500  CXXCastPath &BasePath) {
1501  const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>();
1502  if (!DestMemPtr)
1503  return TC_NotApplicable;
1504 
1505  bool WasOverloadedFunction = false;
1506  DeclAccessPair FoundOverload;
1507  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1508  if (FunctionDecl *Fn
1509  = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(), DestType, false,
1510  FoundOverload)) {
1511  CXXMethodDecl *M = cast<CXXMethodDecl>(Fn);
1512  SrcType = Self.Context.getMemberPointerType(Fn->getType(),
1513  Self.Context.getTypeDeclType(M->getParent()).getTypePtr());
1514  WasOverloadedFunction = true;
1515  }
1516  }
1517 
1518  const MemberPointerType *SrcMemPtr = SrcType->getAs<MemberPointerType>();
1519  if (!SrcMemPtr) {
1520  msg = diag::err_bad_static_cast_member_pointer_nonmp;
1521  return TC_NotApplicable;
1522  }
1523 
1524  // Lock down the inheritance model right now in MS ABI, whether or not the
1525  // pointee types are the same.
1526  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1527  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
1528  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
1529  }
1530 
1531  // T == T, modulo cv
1532  if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
1533  DestMemPtr->getPointeeType()))
1534  return TC_NotApplicable;
1535 
1536  // B base of D
1537  QualType SrcClass(SrcMemPtr->getClass(), 0);
1538  QualType DestClass(DestMemPtr->getClass(), 0);
1539  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1540  /*DetectVirtual=*/true);
1541  if (!Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths))
1542  return TC_NotApplicable;
1543 
1544  // B is a base of D. But is it an allowed base? If not, it's a hard error.
1545  if (Paths.isAmbiguous(Self.Context.getCanonicalType(DestClass))) {
1546  Paths.clear();
1547  Paths.setRecordingPaths(true);
1548  bool StillOkay =
1549  Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths);
1550  assert(StillOkay);
1551  (void)StillOkay;
1552  std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
1553  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
1554  << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
1555  msg = 0;
1556  return TC_Failed;
1557  }
1558 
1559  if (const RecordType *VBase = Paths.getDetectedVirtual()) {
1560  Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
1561  << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
1562  msg = 0;
1563  return TC_Failed;
1564  }
1565 
1566  if (!CStyle) {
1567  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1568  DestClass, SrcClass,
1569  Paths.front(),
1570  diag::err_upcast_to_inaccessible_base)) {
1571  case Sema::AR_accessible:
1572  case Sema::AR_delayed:
1573  case Sema::AR_dependent:
1574  // Optimistically assume that the delayed and dependent cases
1575  // will work out.
1576  break;
1577 
1578  case Sema::AR_inaccessible:
1579  msg = 0;
1580  return TC_Failed;
1581  }
1582  }
1583 
1584  if (WasOverloadedFunction) {
1585  // Resolve the address of the overloaded function again, this time
1586  // allowing complaints if something goes wrong.
1588  DestType,
1589  true,
1590  FoundOverload);
1591  if (!Fn) {
1592  msg = 0;
1593  return TC_Failed;
1594  }
1595 
1596  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr, FoundOverload, Fn);
1597  if (!SrcExpr.isUsable()) {
1598  msg = 0;
1599  return TC_Failed;
1600  }
1601  }
1602 
1603  Self.BuildBasePathArray(Paths, BasePath);
1604  Kind = CK_DerivedToBaseMemberPointer;
1605  return TC_Success;
1606 }
1607 
1608 /// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
1609 /// is valid:
1610 ///
1611 /// An expression e can be explicitly converted to a type T using a
1612 /// @c static_cast if the declaration "T t(e);" is well-formed [...].
1614 TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType,
1616  SourceRange OpRange, unsigned &msg,
1617  CastKind &Kind, bool ListInitialization) {
1618  if (DestType->isRecordType()) {
1619  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
1620  diag::err_bad_dynamic_cast_incomplete) ||
1621  Self.RequireNonAbstractType(OpRange.getBegin(), DestType,
1622  diag::err_allocation_of_abstract_type)) {
1623  msg = 0;
1624  return TC_Failed;
1625  }
1626  }
1627 
1629  InitializationKind InitKind
1630  = (CCK == Sema::CCK_CStyleCast)
1631  ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange,
1632  ListInitialization)
1633  : (CCK == Sema::CCK_FunctionalCast)
1634  ? InitializationKind::CreateFunctionalCast(OpRange, ListInitialization)
1635  : InitializationKind::CreateCast(OpRange);
1636  Expr *SrcExprRaw = SrcExpr.get();
1637  // FIXME: Per DR242, we should check for an implicit conversion sequence
1638  // or for a constructor that could be invoked by direct-initialization
1639  // here, not for an initialization sequence.
1640  InitializationSequence InitSeq(Self, Entity, InitKind, SrcExprRaw);
1641 
1642  // At this point of CheckStaticCast, if the destination is a reference,
1643  // or the expression is an overload expression this has to work.
1644  // There is no other way that works.
1645  // On the other hand, if we're checking a C-style cast, we've still got
1646  // the reinterpret_cast way.
1647  bool CStyle
1648  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1649  if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType()))
1650  return TC_NotApplicable;
1651 
1652  ExprResult Result = InitSeq.Perform(Self, Entity, InitKind, SrcExprRaw);
1653  if (Result.isInvalid()) {
1654  msg = 0;
1655  return TC_Failed;
1656  }
1657 
1658  if (InitSeq.isConstructorInitialization())
1659  Kind = CK_ConstructorConversion;
1660  else
1661  Kind = CK_NoOp;
1662 
1663  SrcExpr = Result;
1664  return TC_Success;
1665 }
1666 
1667 /// TryConstCast - See if a const_cast from source to destination is allowed,
1668 /// and perform it if it is.
1670  QualType DestType, bool CStyle,
1671  unsigned &msg) {
1672  DestType = Self.Context.getCanonicalType(DestType);
1673  QualType SrcType = SrcExpr.get()->getType();
1674  bool NeedToMaterializeTemporary = false;
1675 
1676  if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
1677  // C++11 5.2.11p4:
1678  // if a pointer to T1 can be explicitly converted to the type "pointer to
1679  // T2" using a const_cast, then the following conversions can also be
1680  // made:
1681  // -- an lvalue of type T1 can be explicitly converted to an lvalue of
1682  // type T2 using the cast const_cast<T2&>;
1683  // -- a glvalue of type T1 can be explicitly converted to an xvalue of
1684  // type T2 using the cast const_cast<T2&&>; and
1685  // -- if T1 is a class type, a prvalue of type T1 can be explicitly
1686  // converted to an xvalue of type T2 using the cast const_cast<T2&&>.
1687 
1688  if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr.get()->isLValue()) {
1689  // Cannot const_cast non-lvalue to lvalue reference type. But if this
1690  // is C-style, static_cast might find a way, so we simply suggest a
1691  // message and tell the parent to keep searching.
1692  msg = diag::err_bad_cxx_cast_rvalue;
1693  return TC_NotApplicable;
1694  }
1695 
1696  if (isa<RValueReferenceType>(DestTypeTmp) && SrcExpr.get()->isRValue()) {
1697  if (!SrcType->isRecordType()) {
1698  // Cannot const_cast non-class prvalue to rvalue reference type. But if
1699  // this is C-style, static_cast can do this.
1700  msg = diag::err_bad_cxx_cast_rvalue;
1701  return TC_NotApplicable;
1702  }
1703 
1704  // Materialize the class prvalue so that the const_cast can bind a
1705  // reference to it.
1706  NeedToMaterializeTemporary = true;
1707  }
1708 
1709  // It's not completely clear under the standard whether we can
1710  // const_cast bit-field gl-values. Doing so would not be
1711  // intrinsically complicated, but for now, we say no for
1712  // consistency with other compilers and await the word of the
1713  // committee.
1714  if (SrcExpr.get()->refersToBitField()) {
1715  msg = diag::err_bad_cxx_cast_bitfield;
1716  return TC_NotApplicable;
1717  }
1718 
1719  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
1720  SrcType = Self.Context.getPointerType(SrcType);
1721  }
1722 
1723  // C++ 5.2.11p5: For a const_cast involving pointers to data members [...]
1724  // the rules for const_cast are the same as those used for pointers.
1725 
1726  if (!DestType->isPointerType() &&
1727  !DestType->isMemberPointerType() &&
1728  !DestType->isObjCObjectPointerType()) {
1729  // Cannot cast to non-pointer, non-reference type. Note that, if DestType
1730  // was a reference type, we converted it to a pointer above.
1731  // The status of rvalue references isn't entirely clear, but it looks like
1732  // conversion to them is simply invalid.
1733  // C++ 5.2.11p3: For two pointer types [...]
1734  if (!CStyle)
1735  msg = diag::err_bad_const_cast_dest;
1736  return TC_NotApplicable;
1737  }
1738  if (DestType->isFunctionPointerType() ||
1739  DestType->isMemberFunctionPointerType()) {
1740  // Cannot cast direct function pointers.
1741  // C++ 5.2.11p2: [...] where T is any object type or the void type [...]
1742  // T is the ultimate pointee of source and target type.
1743  if (!CStyle)
1744  msg = diag::err_bad_const_cast_dest;
1745  return TC_NotApplicable;
1746  }
1747 
1748  // C++ [expr.const.cast]p3:
1749  // "For two similar types T1 and T2, [...]"
1750  //
1751  // We only allow a const_cast to change cvr-qualifiers, not other kinds of
1752  // type qualifiers. (Likewise, we ignore other changes when determining
1753  // whether a cast casts away constness.)
1754  if (!Self.Context.hasCvrSimilarType(SrcType, DestType))
1755  return TC_NotApplicable;
1756 
1757  if (NeedToMaterializeTemporary)
1758  // This is a const_cast from a class prvalue to an rvalue reference type.
1759  // Materialize a temporary to store the result of the conversion.
1760  SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcExpr.get()->getType(),
1761  SrcExpr.get(),
1762  /*IsLValueReference*/ false);
1763 
1764  return TC_Success;
1765 }
1766 
1767 // Checks for undefined behavior in reinterpret_cast.
1768 // The cases that is checked for is:
1769 // *reinterpret_cast<T*>(&a)
1770 // reinterpret_cast<T&>(a)
1771 // where accessing 'a' as type 'T' will result in undefined behavior.
1773  bool IsDereference,
1774  SourceRange Range) {
1775  unsigned DiagID = IsDereference ?
1776  diag::warn_pointer_indirection_from_incompatible_type :
1777  diag::warn_undefined_reinterpret_cast;
1778 
1779  if (Diags.isIgnored(DiagID, Range.getBegin()))
1780  return;
1781 
1782  QualType SrcTy, DestTy;
1783  if (IsDereference) {
1784  if (!SrcType->getAs<PointerType>() || !DestType->getAs<PointerType>()) {
1785  return;
1786  }
1787  SrcTy = SrcType->getPointeeType();
1788  DestTy = DestType->getPointeeType();
1789  } else {
1790  if (!DestType->getAs<ReferenceType>()) {
1791  return;
1792  }
1793  SrcTy = SrcType;
1794  DestTy = DestType->getPointeeType();
1795  }
1796 
1797  // Cast is compatible if the types are the same.
1798  if (Context.hasSameUnqualifiedType(DestTy, SrcTy)) {
1799  return;
1800  }
1801  // or one of the types is a char or void type
1802  if (DestTy->isAnyCharacterType() || DestTy->isVoidType() ||
1803  SrcTy->isAnyCharacterType() || SrcTy->isVoidType()) {
1804  return;
1805  }
1806  // or one of the types is a tag type.
1807  if (SrcTy->getAs<TagType>() || DestTy->getAs<TagType>()) {
1808  return;
1809  }
1810 
1811  // FIXME: Scoped enums?
1812  if ((SrcTy->isUnsignedIntegerType() && DestTy->isSignedIntegerType()) ||
1813  (SrcTy->isSignedIntegerType() && DestTy->isUnsignedIntegerType())) {
1814  if (Context.getTypeSize(DestTy) == Context.getTypeSize(SrcTy)) {
1815  return;
1816  }
1817  }
1818 
1819  Diag(Range.getBegin(), DiagID) << SrcType << DestType << Range;
1820 }
1821 
1822 static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr,
1823  QualType DestType) {
1824  QualType SrcType = SrcExpr.get()->getType();
1825  if (Self.Context.hasSameType(SrcType, DestType))
1826  return;
1827  if (const PointerType *SrcPtrTy = SrcType->getAs<PointerType>())
1828  if (SrcPtrTy->isObjCSelType()) {
1829  QualType DT = DestType;
1830  if (isa<PointerType>(DestType))
1831  DT = DestType->getPointeeType();
1832  if (!DT.getUnqualifiedType()->isVoidType())
1833  Self.Diag(SrcExpr.get()->getExprLoc(),
1834  diag::warn_cast_pointer_from_sel)
1835  << SrcType << DestType << SrcExpr.get()->getSourceRange();
1836  }
1837 }
1838 
1839 /// Diagnose casts that change the calling convention of a pointer to a function
1840 /// defined in the current TU.
1841 static void DiagnoseCallingConvCast(Sema &Self, const ExprResult &SrcExpr,
1842  QualType DstType, SourceRange OpRange) {
1843  // Check if this cast would change the calling convention of a function
1844  // pointer type.
1845  QualType SrcType = SrcExpr.get()->getType();
1846  if (Self.Context.hasSameType(SrcType, DstType) ||
1847  !SrcType->isFunctionPointerType() || !DstType->isFunctionPointerType())
1848  return;
1849  const auto *SrcFTy =
1850  SrcType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
1851  const auto *DstFTy =
1852  DstType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
1853  CallingConv SrcCC = SrcFTy->getCallConv();
1854  CallingConv DstCC = DstFTy->getCallConv();
1855  if (SrcCC == DstCC)
1856  return;
1857 
1858  // We have a calling convention cast. Check if the source is a pointer to a
1859  // known, specific function that has already been defined.
1860  Expr *Src = SrcExpr.get()->IgnoreParenImpCasts();
1861  if (auto *UO = dyn_cast<UnaryOperator>(Src))
1862  if (UO->getOpcode() == UO_AddrOf)
1863  Src = UO->getSubExpr()->IgnoreParenImpCasts();
1864  auto *DRE = dyn_cast<DeclRefExpr>(Src);
1865  if (!DRE)
1866  return;
1867  auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
1868  if (!FD)
1869  return;
1870 
1871  // Only warn if we are casting from the default convention to a non-default
1872  // convention. This can happen when the programmer forgot to apply the calling
1873  // convention to the function declaration and then inserted this cast to
1874  // satisfy the type system.
1876  FD->isVariadic(), FD->isCXXInstanceMember());
1877  if (DstCC == DefaultCC || SrcCC != DefaultCC)
1878  return;
1879 
1880  // Diagnose this cast, as it is probably bad.
1881  StringRef SrcCCName = FunctionType::getNameForCallConv(SrcCC);
1882  StringRef DstCCName = FunctionType::getNameForCallConv(DstCC);
1883  Self.Diag(OpRange.getBegin(), diag::warn_cast_calling_conv)
1884  << SrcCCName << DstCCName << OpRange;
1885 
1886  // The checks above are cheaper than checking if the diagnostic is enabled.
1887  // However, it's worth checking if the warning is enabled before we construct
1888  // a fixit.
1889  if (Self.Diags.isIgnored(diag::warn_cast_calling_conv, OpRange.getBegin()))
1890  return;
1891 
1892  // Try to suggest a fixit to change the calling convention of the function
1893  // whose address was taken. Try to use the latest macro for the convention.
1894  // For example, users probably want to write "WINAPI" instead of "__stdcall"
1895  // to match the Windows header declarations.
1896  SourceLocation NameLoc = FD->getFirstDecl()->getNameInfo().getLoc();
1897  Preprocessor &PP = Self.getPreprocessor();
1898  SmallVector<TokenValue, 6> AttrTokens;
1899  SmallString<64> CCAttrText;
1900  llvm::raw_svector_ostream OS(CCAttrText);
1901  if (Self.getLangOpts().MicrosoftExt) {
1902  // __stdcall or __vectorcall
1903  OS << "__" << DstCCName;
1904  IdentifierInfo *II = PP.getIdentifierInfo(OS.str());
1905  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
1906  ? TokenValue(II->getTokenID())
1907  : TokenValue(II));
1908  } else {
1909  // __attribute__((stdcall)) or __attribute__((vectorcall))
1910  OS << "__attribute__((" << DstCCName << "))";
1911  AttrTokens.push_back(tok::kw___attribute);
1912  AttrTokens.push_back(tok::l_paren);
1913  AttrTokens.push_back(tok::l_paren);
1914  IdentifierInfo *II = PP.getIdentifierInfo(DstCCName);
1915  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
1916  ? TokenValue(II->getTokenID())
1917  : TokenValue(II));
1918  AttrTokens.push_back(tok::r_paren);
1919  AttrTokens.push_back(tok::r_paren);
1920  }
1921  StringRef AttrSpelling = PP.getLastMacroWithSpelling(NameLoc, AttrTokens);
1922  if (!AttrSpelling.empty())
1923  CCAttrText = AttrSpelling;
1924  OS << ' ';
1925  Self.Diag(NameLoc, diag::note_change_calling_conv_fixit)
1926  << FD << DstCCName << FixItHint::CreateInsertion(NameLoc, CCAttrText);
1927 }
1928 
1929 static void checkIntToPointerCast(bool CStyle, SourceLocation Loc,
1930  const Expr *SrcExpr, QualType DestType,
1931  Sema &Self) {
1932  QualType SrcType = SrcExpr->getType();
1933 
1934  // Not warning on reinterpret_cast, boolean, constant expressions, etc
1935  // are not explicit design choices, but consistent with GCC's behavior.
1936  // Feel free to modify them if you've reason/evidence for an alternative.
1937  if (CStyle && SrcType->isIntegralType(Self.Context)
1938  && !SrcType->isBooleanType()
1939  && !SrcType->isEnumeralType()
1940  && !SrcExpr->isIntegerConstantExpr(Self.Context)
1941  && Self.Context.getTypeSize(DestType) >
1942  Self.Context.getTypeSize(SrcType)) {
1943  // Separate between casts to void* and non-void* pointers.
1944  // Some APIs use (abuse) void* for something like a user context,
1945  // and often that value is an integer even if it isn't a pointer itself.
1946  // Having a separate warning flag allows users to control the warning
1947  // for their workflow.
1948  unsigned Diag = DestType->isVoidPointerType() ?
1949  diag::warn_int_to_void_pointer_cast
1950  : diag::warn_int_to_pointer_cast;
1951  Self.Diag(Loc, Diag) << SrcType << DestType;
1952  }
1953 }
1954 
1955 static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType,
1956  ExprResult &Result) {
1957  // We can only fix an overloaded reinterpret_cast if
1958  // - it is a template with explicit arguments that resolves to an lvalue
1959  // unambiguously, or
1960  // - it is the only function in an overload set that may have its address
1961  // taken.
1962 
1963  Expr *E = Result.get();
1964  // TODO: what if this fails because of DiagnoseUseOfDecl or something
1965  // like it?
1967  Result,
1968  Expr::getValueKindForType(DestType) == VK_RValue // Convert Fun to Ptr
1969  ) &&
1970  Result.isUsable())
1971  return true;
1972 
1973  // No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
1974  // preserves Result.
1975  Result = E;
1977  Result, /*DoFunctionPointerConversion=*/true))
1978  return false;
1979  return Result.isUsable();
1980 }
1981 
1983  QualType DestType, bool CStyle,
1984  SourceRange OpRange,
1985  unsigned &msg,
1986  CastKind &Kind) {
1987  bool IsLValueCast = false;
1988 
1989  DestType = Self.Context.getCanonicalType(DestType);
1990  QualType SrcType = SrcExpr.get()->getType();
1991 
1992  // Is the source an overloaded name? (i.e. &foo)
1993  // If so, reinterpret_cast generally can not help us here (13.4, p1, bullet 5)
1994  if (SrcType == Self.Context.OverloadTy) {
1995  ExprResult FixedExpr = SrcExpr;
1996  if (!fixOverloadedReinterpretCastExpr(Self, DestType, FixedExpr))
1997  return TC_NotApplicable;
1998 
1999  assert(FixedExpr.isUsable() && "Invalid result fixing overloaded expr");
2000  SrcExpr = FixedExpr;
2001  SrcType = SrcExpr.get()->getType();
2002  }
2003 
2004  if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
2005  if (!SrcExpr.get()->isGLValue()) {
2006  // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
2007  // similar comment in const_cast.
2008  msg = diag::err_bad_cxx_cast_rvalue;
2009  return TC_NotApplicable;
2010  }
2011 
2012  if (!CStyle) {
2013  Self.CheckCompatibleReinterpretCast(SrcType, DestType,
2014  /*isDereference=*/false, OpRange);
2015  }
2016 
2017  // C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
2018  // same effect as the conversion *reinterpret_cast<T*>(&x) with the
2019  // built-in & and * operators.
2020 
2021  const char *inappropriate = nullptr;
2022  switch (SrcExpr.get()->getObjectKind()) {
2023  case OK_Ordinary:
2024  break;
2025  case OK_BitField:
2026  msg = diag::err_bad_cxx_cast_bitfield;
2027  return TC_NotApplicable;
2028  // FIXME: Use a specific diagnostic for the rest of these cases.
2029  case OK_VectorComponent: inappropriate = "vector element"; break;
2030  case OK_ObjCProperty: inappropriate = "property expression"; break;
2031  case OK_ObjCSubscript: inappropriate = "container subscripting expression";
2032  break;
2033  }
2034  if (inappropriate) {
2035  Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
2036  << inappropriate << DestType
2037  << OpRange << SrcExpr.get()->getSourceRange();
2038  msg = 0; SrcExpr = ExprError();
2039  return TC_NotApplicable;
2040  }
2041 
2042  // This code does this transformation for the checked types.
2043  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
2044  SrcType = Self.Context.getPointerType(SrcType);
2045 
2046  IsLValueCast = true;
2047  }
2048 
2049  // Canonicalize source for comparison.
2050  SrcType = Self.Context.getCanonicalType(SrcType);
2051 
2052  const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>(),
2053  *SrcMemPtr = SrcType->getAs<MemberPointerType>();
2054  if (DestMemPtr && SrcMemPtr) {
2055  // C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
2056  // can be explicitly converted to an rvalue of type "pointer to member
2057  // of Y of type T2" if T1 and T2 are both function types or both object
2058  // types.
2059  if (DestMemPtr->isMemberFunctionPointer() !=
2060  SrcMemPtr->isMemberFunctionPointer())
2061  return TC_NotApplicable;
2062 
2063  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2064  // We need to determine the inheritance model that the class will use if
2065  // haven't yet.
2066  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
2067  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
2068  }
2069 
2070  // Don't allow casting between member pointers of different sizes.
2071  if (Self.Context.getTypeSize(DestMemPtr) !=
2072  Self.Context.getTypeSize(SrcMemPtr)) {
2073  msg = diag::err_bad_cxx_cast_member_pointer_size;
2074  return TC_Failed;
2075  }
2076 
2077  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
2078  // constness.
2079  // A reinterpret_cast followed by a const_cast can, though, so in C-style,
2080  // we accept it.
2081  if (auto CACK =
2082  CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2083  /*CheckObjCLifetime=*/CStyle))
2084  return getCastAwayConstnessCastKind(CACK, msg);
2085 
2086  // A valid member pointer cast.
2087  assert(!IsLValueCast);
2088  Kind = CK_ReinterpretMemberPointer;
2089  return TC_Success;
2090  }
2091 
2092  // See below for the enumeral issue.
2093  if (SrcType->isNullPtrType() && DestType->isIntegralType(Self.Context)) {
2094  // C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
2095  // type large enough to hold it. A value of std::nullptr_t can be
2096  // converted to an integral type; the conversion has the same meaning
2097  // and validity as a conversion of (void*)0 to the integral type.
2098  if (Self.Context.getTypeSize(SrcType) >
2099  Self.Context.getTypeSize(DestType)) {
2100  msg = diag::err_bad_reinterpret_cast_small_int;
2101  return TC_Failed;
2102  }
2103  Kind = CK_PointerToIntegral;
2104  return TC_Success;
2105  }
2106 
2107  // Allow reinterpret_casts between vectors of the same size and
2108  // between vectors and integers of the same size.
2109  bool destIsVector = DestType->isVectorType();
2110  bool srcIsVector = SrcType->isVectorType();
2111  if (srcIsVector || destIsVector) {
2112  // The non-vector type, if any, must have integral type. This is
2113  // the same rule that C vector casts use; note, however, that enum
2114  // types are not integral in C++.
2115  if ((!destIsVector && !DestType->isIntegralType(Self.Context)) ||
2116  (!srcIsVector && !SrcType->isIntegralType(Self.Context)))
2117  return TC_NotApplicable;
2118 
2119  // The size we want to consider is eltCount * eltSize.
2120  // That's exactly what the lax-conversion rules will check.
2121  if (Self.areLaxCompatibleVectorTypes(SrcType, DestType)) {
2122  Kind = CK_BitCast;
2123  return TC_Success;
2124  }
2125 
2126  // Otherwise, pick a reasonable diagnostic.
2127  if (!destIsVector)
2128  msg = diag::err_bad_cxx_cast_vector_to_scalar_different_size;
2129  else if (!srcIsVector)
2130  msg = diag::err_bad_cxx_cast_scalar_to_vector_different_size;
2131  else
2132  msg = diag::err_bad_cxx_cast_vector_to_vector_different_size;
2133 
2134  return TC_Failed;
2135  }
2136 
2137  if (SrcType == DestType) {
2138  // C++ 5.2.10p2 has a note that mentions that, subject to all other
2139  // restrictions, a cast to the same type is allowed so long as it does not
2140  // cast away constness. In C++98, the intent was not entirely clear here,
2141  // since all other paragraphs explicitly forbid casts to the same type.
2142  // C++11 clarifies this case with p2.
2143  //
2144  // The only allowed types are: integral, enumeration, pointer, or
2145  // pointer-to-member types. We also won't restrict Obj-C pointers either.
2146  Kind = CK_NoOp;
2148  if (SrcType->isIntegralOrEnumerationType() ||
2149  SrcType->isAnyPointerType() ||
2150  SrcType->isMemberPointerType() ||
2151  SrcType->isBlockPointerType()) {
2152  Result = TC_Success;
2153  }
2154  return Result;
2155  }
2156 
2157  bool destIsPtr = DestType->isAnyPointerType() ||
2158  DestType->isBlockPointerType();
2159  bool srcIsPtr = SrcType->isAnyPointerType() ||
2160  SrcType->isBlockPointerType();
2161  if (!destIsPtr && !srcIsPtr) {
2162  // Except for std::nullptr_t->integer and lvalue->reference, which are
2163  // handled above, at least one of the two arguments must be a pointer.
2164  return TC_NotApplicable;
2165  }
2166 
2167  if (DestType->isIntegralType(Self.Context)) {
2168  assert(srcIsPtr && "One type must be a pointer");
2169  // C++ 5.2.10p4: A pointer can be explicitly converted to any integral
2170  // type large enough to hold it; except in Microsoft mode, where the
2171  // integral type size doesn't matter (except we don't allow bool).
2172  bool MicrosoftException = Self.getLangOpts().MicrosoftExt &&
2173  !DestType->isBooleanType();
2174  if ((Self.Context.getTypeSize(SrcType) >
2175  Self.Context.getTypeSize(DestType)) &&
2176  !MicrosoftException) {
2177  msg = diag::err_bad_reinterpret_cast_small_int;
2178  return TC_Failed;
2179  }
2180  Kind = CK_PointerToIntegral;
2181  return TC_Success;
2182  }
2183 
2184  if (SrcType->isIntegralOrEnumerationType()) {
2185  assert(destIsPtr && "One type must be a pointer");
2186  checkIntToPointerCast(CStyle, OpRange.getBegin(), SrcExpr.get(), DestType,
2187  Self);
2188  // C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
2189  // converted to a pointer.
2190  // C++ 5.2.10p9: [Note: ...a null pointer constant of integral type is not
2191  // necessarily converted to a null pointer value.]
2192  Kind = CK_IntegralToPointer;
2193  return TC_Success;
2194  }
2195 
2196  if (!destIsPtr || !srcIsPtr) {
2197  // With the valid non-pointer conversions out of the way, we can be even
2198  // more stringent.
2199  return TC_NotApplicable;
2200  }
2201 
2202  // Cannot convert between block pointers and Objective-C object pointers.
2203  if ((SrcType->isBlockPointerType() && DestType->isObjCObjectPointerType()) ||
2204  (DestType->isBlockPointerType() && SrcType->isObjCObjectPointerType()))
2205  return TC_NotApplicable;
2206 
2207  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
2208  // The C-style cast operator can.
2209  TryCastResult SuccessResult = TC_Success;
2210  if (auto CACK =
2211  CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2212  /*CheckObjCLifetime=*/CStyle))
2213  SuccessResult = getCastAwayConstnessCastKind(CACK, msg);
2214 
2215  if (IsAddressSpaceConversion(SrcType, DestType)) {
2216  Kind = CK_AddressSpaceConversion;
2217  assert(SrcType->isPointerType() && DestType->isPointerType());
2218  if (!CStyle &&
2220  SrcType->getPointeeType().getQualifiers())) {
2221  SuccessResult = TC_Failed;
2222  }
2223  } else if (IsLValueCast) {
2224  Kind = CK_LValueBitCast;
2225  } else if (DestType->isObjCObjectPointerType()) {
2226  Kind = Self.PrepareCastToObjCObjectPointer(SrcExpr);
2227  } else if (DestType->isBlockPointerType()) {
2228  if (!SrcType->isBlockPointerType()) {
2229  Kind = CK_AnyPointerToBlockPointerCast;
2230  } else {
2231  Kind = CK_BitCast;
2232  }
2233  } else {
2234  Kind = CK_BitCast;
2235  }
2236 
2237  // Any pointer can be cast to an Objective-C pointer type with a C-style
2238  // cast.
2239  if (CStyle && DestType->isObjCObjectPointerType()) {
2240  return SuccessResult;
2241  }
2242  if (CStyle)
2243  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2244 
2245  DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
2246 
2247  // Not casting away constness, so the only remaining check is for compatible
2248  // pointer categories.
2249 
2250  if (SrcType->isFunctionPointerType()) {
2251  if (DestType->isFunctionPointerType()) {
2252  // C++ 5.2.10p6: A pointer to a function can be explicitly converted to
2253  // a pointer to a function of a different type.
2254  return SuccessResult;
2255  }
2256 
2257  // C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
2258  // an object type or vice versa is conditionally-supported.
2259  // Compilers support it in C++03 too, though, because it's necessary for
2260  // casting the return value of dlsym() and GetProcAddress().
2261  // FIXME: Conditionally-supported behavior should be configurable in the
2262  // TargetInfo or similar.
2263  Self.Diag(OpRange.getBegin(),
2264  Self.getLangOpts().CPlusPlus11 ?
2265  diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2266  << OpRange;
2267  return SuccessResult;
2268  }
2269 
2270  if (DestType->isFunctionPointerType()) {
2271  // See above.
2272  Self.Diag(OpRange.getBegin(),
2273  Self.getLangOpts().CPlusPlus11 ?
2274  diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2275  << OpRange;
2276  return SuccessResult;
2277  }
2278 
2279  // C++ 5.2.10p7: A pointer to an object can be explicitly converted to
2280  // a pointer to an object of different type.
2281  // Void pointers are not specified, but supported by every compiler out there.
2282  // So we finish by allowing everything that remains - it's got to be two
2283  // object pointers.
2284  return SuccessResult;
2285 }
2286 
2288  QualType DestType, bool CStyle,
2289  unsigned &msg) {
2290  if (!Self.getLangOpts().OpenCL)
2291  // FIXME: As compiler doesn't have any information about overlapping addr
2292  // spaces at the moment we have to be permissive here.
2293  return TC_NotApplicable;
2294  // Even though the logic below is general enough and can be applied to
2295  // non-OpenCL mode too, we fast-path above because no other languages
2296  // define overlapping address spaces currently.
2297  auto SrcType = SrcExpr.get()->getType();
2298  auto SrcPtrType = SrcType->getAs<PointerType>();
2299  if (!SrcPtrType)
2300  return TC_NotApplicable;
2301  auto DestPtrType = DestType->getAs<PointerType>();
2302  if (!DestPtrType)
2303  return TC_NotApplicable;
2304  auto SrcPointeeType = SrcPtrType->getPointeeType();
2305  auto DestPointeeType = DestPtrType->getPointeeType();
2306  if (SrcPointeeType.getAddressSpace() == DestPointeeType.getAddressSpace())
2307  return TC_NotApplicable;
2308  if (!DestPtrType->isAddressSpaceOverlapping(*SrcPtrType)) {
2309  msg = diag::err_bad_cxx_cast_addr_space_mismatch;
2310  return TC_Failed;
2311  }
2312  auto SrcPointeeTypeWithoutAS =
2313  Self.Context.removeAddrSpaceQualType(SrcPointeeType.getCanonicalType());
2314  auto DestPointeeTypeWithoutAS =
2315  Self.Context.removeAddrSpaceQualType(DestPointeeType.getCanonicalType());
2316  return Self.Context.hasSameType(SrcPointeeTypeWithoutAS,
2317  DestPointeeTypeWithoutAS)
2318  ? TC_Success
2319  : TC_NotApplicable;
2320 }
2321 
2322 void CastOperation::checkAddressSpaceCast(QualType SrcType, QualType DestType) {
2323  // In OpenCL only conversions between pointers to objects in overlapping
2324  // addr spaces are allowed. v2.0 s6.5.5 - Generic addr space overlaps
2325  // with any named one, except for constant.
2326  if (Self.getLangOpts().OpenCL) {
2327  auto SrcPtrType = SrcType->getAs<PointerType>();
2328  if (!SrcPtrType)
2329  return;
2330  auto DestPtrType = DestType->getAs<PointerType>();
2331  if (!DestPtrType)
2332  return;
2333  if (!DestPtrType->isAddressSpaceOverlapping(*SrcPtrType)) {
2334  Self.Diag(OpRange.getBegin(),
2335  diag::err_typecheck_incompatible_address_space)
2336  << SrcType << DestType << Sema::AA_Casting
2337  << SrcExpr.get()->getSourceRange();
2338  SrcExpr = ExprError();
2339  }
2340  }
2341 }
2342 
2343 void CastOperation::CheckCXXCStyleCast(bool FunctionalStyle,
2344  bool ListInitialization) {
2345  assert(Self.getLangOpts().CPlusPlus);
2346 
2347  // Handle placeholders.
2348  if (isPlaceholder()) {
2349  // C-style casts can resolve __unknown_any types.
2350  if (claimPlaceholder(BuiltinType::UnknownAny)) {
2351  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2352  SrcExpr.get(), Kind,
2353  ValueKind, BasePath);
2354  return;
2355  }
2356 
2357  checkNonOverloadPlaceholders();
2358  if (SrcExpr.isInvalid())
2359  return;
2360  }
2361 
2362  // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
2363  // This test is outside everything else because it's the only case where
2364  // a non-lvalue-reference target type does not lead to decay.
2365  if (DestType->isVoidType()) {
2366  Kind = CK_ToVoid;
2367 
2368  if (claimPlaceholder(BuiltinType::Overload)) {
2370  SrcExpr, /* Decay Function to ptr */ false,
2371  /* Complain */ true, DestRange, DestType,
2372  diag::err_bad_cstyle_cast_overload);
2373  if (SrcExpr.isInvalid())
2374  return;
2375  }
2376 
2377  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2378  return;
2379  }
2380 
2381  // If the type is dependent, we won't do any other semantic analysis now.
2382  if (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
2383  SrcExpr.get()->isValueDependent()) {
2384  assert(Kind == CK_Dependent);
2385  return;
2386  }
2387 
2388  if (ValueKind == VK_RValue && !DestType->isRecordType() &&
2389  !isPlaceholder(BuiltinType::Overload)) {
2390  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2391  if (SrcExpr.isInvalid())
2392  return;
2393  }
2394 
2395  // AltiVec vector initialization with a single literal.
2396  if (const VectorType *vecTy = DestType->getAs<VectorType>())
2397  if (vecTy->getVectorKind() == VectorType::AltiVecVector
2398  && (SrcExpr.get()->getType()->isIntegerType()
2399  || SrcExpr.get()->getType()->isFloatingType())) {
2400  Kind = CK_VectorSplat;
2401  SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2402  return;
2403  }
2404 
2405  // C++ [expr.cast]p5: The conversions performed by
2406  // - a const_cast,
2407  // - a static_cast,
2408  // - a static_cast followed by a const_cast,
2409  // - a reinterpret_cast, or
2410  // - a reinterpret_cast followed by a const_cast,
2411  // can be performed using the cast notation of explicit type conversion.
2412  // [...] If a conversion can be interpreted in more than one of the ways
2413  // listed above, the interpretation that appears first in the list is used,
2414  // even if a cast resulting from that interpretation is ill-formed.
2415  // In plain language, this means trying a const_cast ...
2416  // Note that for address space we check compatibility after const_cast.
2417  unsigned msg = diag::err_bad_cxx_cast_generic;
2418  TryCastResult tcr = TryConstCast(Self, SrcExpr, DestType,
2419  /*CStyle*/ true, msg);
2420  if (SrcExpr.isInvalid())
2421  return;
2422  if (isValidCast(tcr))
2423  Kind = CK_NoOp;
2424 
2426  FunctionalStyle ? Sema::CCK_FunctionalCast : Sema::CCK_CStyleCast;
2427  if (tcr == TC_NotApplicable) {
2428  tcr = TryAddressSpaceCast(Self, SrcExpr, DestType, /*CStyle*/ true, msg);
2429  if (SrcExpr.isInvalid())
2430  return;
2431  if (tcr == TC_NotApplicable) {
2432  // ... or if that is not possible, a static_cast, ignoring const, ...
2433  tcr = TryStaticCast(Self, SrcExpr, DestType, CCK, OpRange, msg, Kind,
2434  BasePath, ListInitialization);
2435  if (SrcExpr.isInvalid())
2436  return;
2437 
2438  if (tcr == TC_NotApplicable) {
2439  // ... and finally a reinterpret_cast, ignoring const.
2440  tcr = TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/ true,
2441  OpRange, msg, Kind);
2442  if (SrcExpr.isInvalid())
2443  return;
2444  }
2445  }
2446  }
2447 
2449  isValidCast(tcr))
2450  checkObjCConversion(CCK);
2451 
2452  if (tcr != TC_Success && msg != 0) {
2453  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2454  DeclAccessPair Found;
2456  DestType,
2457  /*Complain*/ true,
2458  Found);
2459  if (Fn) {
2460  // If DestType is a function type (not to be confused with the function
2461  // pointer type), it will be possible to resolve the function address,
2462  // but the type cast should be considered as failure.
2463  OverloadExpr *OE = OverloadExpr::find(SrcExpr.get()).Expression;
2464  Self.Diag(OpRange.getBegin(), diag::err_bad_cstyle_cast_overload)
2465  << OE->getName() << DestType << OpRange
2466  << OE->getQualifierLoc().getSourceRange();
2467  Self.NoteAllOverloadCandidates(SrcExpr.get());
2468  }
2469  } else {
2470  diagnoseBadCast(Self, msg, (FunctionalStyle ? CT_Functional : CT_CStyle),
2471  OpRange, SrcExpr.get(), DestType, ListInitialization);
2472  }
2473  }
2474 
2475  if (isValidCast(tcr)) {
2476  if (Kind == CK_BitCast)
2477  checkCastAlign();
2478  } else {
2479  SrcExpr = ExprError();
2480  }
2481 }
2482 
2483 /// DiagnoseBadFunctionCast - Warn whenever a function call is cast to a
2484 /// non-matching type. Such as enum function call to int, int call to
2485 /// pointer; etc. Cast to 'void' is an exception.
2486 static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr,
2487  QualType DestType) {
2488  if (Self.Diags.isIgnored(diag::warn_bad_function_cast,
2489  SrcExpr.get()->getExprLoc()))
2490  return;
2491 
2492  if (!isa<CallExpr>(SrcExpr.get()))
2493  return;
2494 
2495  QualType SrcType = SrcExpr.get()->getType();
2496  if (DestType.getUnqualifiedType()->isVoidType())
2497  return;
2498  if ((SrcType->isAnyPointerType() || SrcType->isBlockPointerType())
2499  && (DestType->isAnyPointerType() || DestType->isBlockPointerType()))
2500  return;
2501  if (SrcType->isIntegerType() && DestType->isIntegerType() &&
2502  (SrcType->isBooleanType() == DestType->isBooleanType()) &&
2503  (SrcType->isEnumeralType() == DestType->isEnumeralType()))
2504  return;
2505  if (SrcType->isRealFloatingType() && DestType->isRealFloatingType())
2506  return;
2507  if (SrcType->isEnumeralType() && DestType->isEnumeralType())
2508  return;
2509  if (SrcType->isComplexType() && DestType->isComplexType())
2510  return;
2511  if (SrcType->isComplexIntegerType() && DestType->isComplexIntegerType())
2512  return;
2513 
2514  Self.Diag(SrcExpr.get()->getExprLoc(),
2515  diag::warn_bad_function_cast)
2516  << SrcType << DestType << SrcExpr.get()->getSourceRange();
2517 }
2518 
2519 /// Check the semantics of a C-style cast operation, in C.
2520 void CastOperation::CheckCStyleCast() {
2521  assert(!Self.getLangOpts().CPlusPlus);
2522 
2523  // C-style casts can resolve __unknown_any types.
2524  if (claimPlaceholder(BuiltinType::UnknownAny)) {
2525  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2526  SrcExpr.get(), Kind,
2527  ValueKind, BasePath);
2528  return;
2529  }
2530 
2531  // C99 6.5.4p2: the cast type needs to be void or scalar and the expression
2532  // type needs to be scalar.
2533  if (DestType->isVoidType()) {
2534  // We don't necessarily do lvalue-to-rvalue conversions on this.
2535  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2536  if (SrcExpr.isInvalid())
2537  return;
2538 
2539  // Cast to void allows any expr type.
2540  Kind = CK_ToVoid;
2541  return;
2542  }
2543 
2544  // Overloads are allowed with C extensions, so we need to support them.
2545  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2546  DeclAccessPair DAP;
2548  SrcExpr.get(), DestType, /*Complain=*/true, DAP))
2549  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr.get(), DAP, FD);
2550  else
2551  return;
2552  assert(SrcExpr.isUsable());
2553  }
2554  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2555  if (SrcExpr.isInvalid())
2556  return;
2557  QualType SrcType = SrcExpr.get()->getType();
2558 
2559  assert(!SrcType->isPlaceholderType());
2560 
2561  checkAddressSpaceCast(SrcType, DestType);
2562  if (SrcExpr.isInvalid())
2563  return;
2564 
2565  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
2566  diag::err_typecheck_cast_to_incomplete)) {
2567  SrcExpr = ExprError();
2568  return;
2569  }
2570 
2571  if (!DestType->isScalarType() && !DestType->isVectorType()) {
2572  const RecordType *DestRecordTy = DestType->getAs<RecordType>();
2573 
2574  if (DestRecordTy && Self.Context.hasSameUnqualifiedType(DestType, SrcType)){
2575  // GCC struct/union extension: allow cast to self.
2576  Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_nonscalar)
2577  << DestType << SrcExpr.get()->getSourceRange();
2578  Kind = CK_NoOp;
2579  return;
2580  }
2581 
2582  // GCC's cast to union extension.
2583  if (DestRecordTy && DestRecordTy->getDecl()->isUnion()) {
2584  RecordDecl *RD = DestRecordTy->getDecl();
2585  if (CastExpr::getTargetFieldForToUnionCast(RD, SrcType)) {
2586  Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_to_union)
2587  << SrcExpr.get()->getSourceRange();
2588  Kind = CK_ToUnion;
2589  return;
2590  } else {
2591  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cast_to_union_no_type)
2592  << SrcType << SrcExpr.get()->getSourceRange();
2593  SrcExpr = ExprError();
2594  return;
2595  }
2596  }
2597 
2598  // OpenCL v2.0 s6.13.10 - Allow casts from '0' to event_t type.
2599  if (Self.getLangOpts().OpenCL && DestType->isEventT()) {
2601  if (SrcExpr.get()->EvaluateAsInt(Result, Self.Context)) {
2602  llvm::APSInt CastInt = Result.Val.getInt();
2603  if (0 == CastInt) {
2604  Kind = CK_ZeroToOCLOpaqueType;
2605  return;
2606  }
2607  Self.Diag(OpRange.getBegin(),
2608  diag::err_opencl_cast_non_zero_to_event_t)
2609  << CastInt.toString(10) << SrcExpr.get()->getSourceRange();
2610  SrcExpr = ExprError();
2611  return;
2612  }
2613  }
2614 
2615  // Reject any other conversions to non-scalar types.
2616  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cond_expect_scalar)
2617  << DestType << SrcExpr.get()->getSourceRange();
2618  SrcExpr = ExprError();
2619  return;
2620  }
2621 
2622  // The type we're casting to is known to be a scalar or vector.
2623 
2624  // Require the operand to be a scalar or vector.
2625  if (!SrcType->isScalarType() && !SrcType->isVectorType()) {
2626  Self.Diag(SrcExpr.get()->getExprLoc(),
2627  diag::err_typecheck_expect_scalar_operand)
2628  << SrcType << SrcExpr.get()->getSourceRange();
2629  SrcExpr = ExprError();
2630  return;
2631  }
2632 
2633  if (DestType->isExtVectorType()) {
2634  SrcExpr = Self.CheckExtVectorCast(OpRange, DestType, SrcExpr.get(), Kind);
2635  return;
2636  }
2637 
2638  if (const VectorType *DestVecTy = DestType->getAs<VectorType>()) {
2639  if (DestVecTy->getVectorKind() == VectorType::AltiVecVector &&
2640  (SrcType->isIntegerType() || SrcType->isFloatingType())) {
2641  Kind = CK_VectorSplat;
2642  SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2643  } else if (Self.CheckVectorCast(OpRange, DestType, SrcType, Kind)) {
2644  SrcExpr = ExprError();
2645  }
2646  return;
2647  }
2648 
2649  if (SrcType->isVectorType()) {
2650  if (Self.CheckVectorCast(OpRange, SrcType, DestType, Kind))
2651  SrcExpr = ExprError();
2652  return;
2653  }
2654 
2655  // The source and target types are both scalars, i.e.
2656  // - arithmetic types (fundamental, enum, and complex)
2657  // - all kinds of pointers
2658  // Note that member pointers were filtered out with C++, above.
2659 
2660  if (isa<ObjCSelectorExpr>(SrcExpr.get())) {
2661  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_selector_expr);
2662  SrcExpr = ExprError();
2663  return;
2664  }
2665 
2666  // If either type is a pointer, the other type has to be either an
2667  // integer or a pointer.
2668  if (!DestType->isArithmeticType()) {
2669  if (!SrcType->isIntegralType(Self.Context) && SrcType->isArithmeticType()) {
2670  Self.Diag(SrcExpr.get()->getExprLoc(),
2671  diag::err_cast_pointer_from_non_pointer_int)
2672  << SrcType << SrcExpr.get()->getSourceRange();
2673  SrcExpr = ExprError();
2674  return;
2675  }
2676  checkIntToPointerCast(/* CStyle */ true, OpRange.getBegin(), SrcExpr.get(),
2677  DestType, Self);
2678  } else if (!SrcType->isArithmeticType()) {
2679  if (!DestType->isIntegralType(Self.Context) &&
2680  DestType->isArithmeticType()) {
2681  Self.Diag(SrcExpr.get()->getBeginLoc(),
2682  diag::err_cast_pointer_to_non_pointer_int)
2683  << DestType << SrcExpr.get()->getSourceRange();
2684  SrcExpr = ExprError();
2685  return;
2686  }
2687  }
2688 
2689  if (Self.getLangOpts().OpenCL &&
2690  !Self.getOpenCLOptions().isEnabled("cl_khr_fp16")) {
2691  if (DestType->isHalfType()) {
2692  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::err_opencl_cast_to_half)
2693  << DestType << SrcExpr.get()->getSourceRange();
2694  SrcExpr = ExprError();
2695  return;
2696  }
2697  }
2698 
2699  // ARC imposes extra restrictions on casts.
2701  checkObjCConversion(Sema::CCK_CStyleCast);
2702  if (SrcExpr.isInvalid())
2703  return;
2704 
2705  const PointerType *CastPtr = DestType->getAs<PointerType>();
2706  if (Self.getLangOpts().ObjCAutoRefCount && CastPtr) {
2707  if (const PointerType *ExprPtr = SrcType->getAs<PointerType>()) {
2708  Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers();
2709  Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers();
2710  if (CastPtr->getPointeeType()->isObjCLifetimeType() &&
2711  ExprPtr->getPointeeType()->isObjCLifetimeType() &&
2712  !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) {
2713  Self.Diag(SrcExpr.get()->getBeginLoc(),
2714  diag::err_typecheck_incompatible_ownership)
2715  << SrcType << DestType << Sema::AA_Casting
2716  << SrcExpr.get()->getSourceRange();
2717  return;
2718  }
2719  }
2720  }
2721  else if (!Self.CheckObjCARCUnavailableWeakConversion(DestType, SrcType)) {
2722  Self.Diag(SrcExpr.get()->getBeginLoc(),
2723  diag::err_arc_convesion_of_weak_unavailable)
2724  << 1 << SrcType << DestType << SrcExpr.get()->getSourceRange();
2725  SrcExpr = ExprError();
2726  return;
2727  }
2728  }
2729 
2730  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2731  DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
2732  DiagnoseBadFunctionCast(Self, SrcExpr, DestType);
2733  Kind = Self.PrepareScalarCast(SrcExpr, DestType);
2734  if (SrcExpr.isInvalid())
2735  return;
2736 
2737  if (Kind == CK_BitCast)
2738  checkCastAlign();
2739 }
2740 
2741 /// DiagnoseCastQual - Warn whenever casts discards a qualifiers, be it either
2742 /// const, volatile or both.
2743 static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
2744  QualType DestType) {
2745  if (SrcExpr.isInvalid())
2746  return;
2747 
2748  QualType SrcType = SrcExpr.get()->getType();
2749  if (!((SrcType->isAnyPointerType() && DestType->isAnyPointerType()) ||
2750  DestType->isLValueReferenceType()))
2751  return;
2752 
2753  QualType TheOffendingSrcType, TheOffendingDestType;
2754  Qualifiers CastAwayQualifiers;
2755  if (CastsAwayConstness(Self, SrcType, DestType, true, false,
2756  &TheOffendingSrcType, &TheOffendingDestType,
2757  &CastAwayQualifiers) !=
2758  CastAwayConstnessKind::CACK_Similar)
2759  return;
2760 
2761  // FIXME: 'restrict' is not properly handled here.
2762  int qualifiers = -1;
2763  if (CastAwayQualifiers.hasConst() && CastAwayQualifiers.hasVolatile()) {
2764  qualifiers = 0;
2765  } else if (CastAwayQualifiers.hasConst()) {
2766  qualifiers = 1;
2767  } else if (CastAwayQualifiers.hasVolatile()) {
2768  qualifiers = 2;
2769  }
2770  // This is a variant of int **x; const int **y = (const int **)x;
2771  if (qualifiers == -1)
2772  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual2)
2773  << SrcType << DestType;
2774  else
2775  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual)
2776  << TheOffendingSrcType << TheOffendingDestType << qualifiers;
2777 }
2778 
2780  TypeSourceInfo *CastTypeInfo,
2781  SourceLocation RPLoc,
2782  Expr *CastExpr) {
2783  CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
2784  Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2785  Op.OpRange = SourceRange(LPLoc, CastExpr->getEndLoc());
2786 
2787  if (getLangOpts().CPlusPlus) {
2788  Op.CheckCXXCStyleCast(/*FunctionalStyle=*/ false,
2789  isa<InitListExpr>(CastExpr));
2790  } else {
2791  Op.CheckCStyleCast();
2792  }
2793 
2794  if (Op.SrcExpr.isInvalid())
2795  return ExprError();
2796 
2797  // -Wcast-qual
2798  DiagnoseCastQual(Op.Self, Op.SrcExpr, Op.DestType);
2799 
2800  return Op.complete(CStyleCastExpr::Create(Context, Op.ResultType,
2801  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
2802  &Op.BasePath, CastTypeInfo, LPLoc, RPLoc));
2803 }
2804 
2806  QualType Type,
2807  SourceLocation LPLoc,
2808  Expr *CastExpr,
2809  SourceLocation RPLoc) {
2810  assert(LPLoc.isValid() && "List-initialization shouldn't get here.");
2811  CastOperation Op(*this, Type, CastExpr);
2812  Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2813  Op.OpRange = SourceRange(Op.DestRange.getBegin(), CastExpr->getEndLoc());
2814 
2815  Op.CheckCXXCStyleCast(/*FunctionalStyle=*/true, /*ListInit=*/false);
2816  if (Op.SrcExpr.isInvalid())
2817  return ExprError();
2818 
2819  auto *SubExpr = Op.SrcExpr.get();
2820  if (auto *BindExpr = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
2821  SubExpr = BindExpr->getSubExpr();
2822  if (auto *ConstructExpr = dyn_cast<CXXConstructExpr>(SubExpr))
2823  ConstructExpr->setParenOrBraceRange(SourceRange(LPLoc, RPLoc));
2824 
2825  return Op.complete(CXXFunctionalCastExpr::Create(Context, Op.ResultType,
2826  Op.ValueKind, CastTypeInfo, Op.Kind,
2827  Op.SrcExpr.get(), &Op.BasePath, LPLoc, RPLoc));
2828 }
Defines the clang::ASTContext interface.
bool RequireNonAbstractType(SourceLocation Loc, QualType T, TypeDiagnoser &Diagnoser)
Represents a function declaration or definition.
Definition: Decl.h:1737
static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType)
Definition: SemaCast.cpp:1049
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:2547
QualType getPointeeType() const
Definition: Type.h:2560
A (possibly-)qualified type.
Definition: Type.h:639
bool isBlockPointerType() const
Definition: Type.h:6314
bool isMemberPointerType() const
Definition: Type.h:6337
IdentifierInfo * getIdentifierInfo(StringRef Name) const
Return information about the specified preprocessor identifier token.
A cast other than a C-style cast.
Definition: Sema.h:9531
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:1974
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3365
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:505
CharUnits getBaseClassOffset(const CXXRecordDecl *Base) const
getBaseClassOffset - Get the offset, in chars, for the given base class.
Definition: RecordLayout.h:232
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:712
bool isRealFloatingType() const
Floating point categories.
Definition: Type.cpp:1959
bool isRecordType() const
Definition: Type.h:6379
SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID)
Emit a diagnostic.
Definition: Sema.h:1358
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:1063
bool isExtVectorType() const
Definition: Type.h:6395
The cast method is appropriate and successful.
Definition: SemaCast.cpp:34
FailureKind getFailureKind() const
Determine why initialization failed.
CanQualType ARCUnbridgedCastTy
Definition: ASTContext.h:1046
The base class of the type hierarchy.
Definition: Type.h:1414
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:397
Overloading for a user-defined conversion failed.
bool isZero() const
isZero - Test whether the quantity equals zero.
Definition: CharUnits.h:115
Ambiguous candidates found.
Definition: Overload.h:59
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:689
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:808
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:47
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:3168
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:1906
bool CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, CastKind &Kind)
Definition: SemaExpr.cpp:6365
An Objective-C array/dictionary subscripting which reads an object or writes at the subscripted array...
Definition: Specifiers.h:140
Information about one declarator, including the parsed type information and the identifier.
Definition: DeclSpec.h:1764
void removeObjCLifetime()
Definition: Type.h:333
DiagnosticsEngine & Diags
Definition: Sema.h:376
bool isEnumeralType() const
Definition: Type.h:6383
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:1841
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6766
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:454
QualType getMemberPointerType(QualType T, const Type *Cls) const
Return the uniqued reference to the type for a member pointer to the specified type in the specified ...
DeclarationName getName() const
Gets the name looked up.
Definition: ExprCXX.h:2743
bool isInvalidDecl() const
Definition: DeclBase.h:544
OpenCLOptions & getOpenCLOptions()
Definition: Sema.h:1282
Defines the clang::Expr interface and subclasses for C++ expressions.
The collection of all-type qualifiers we support.
Definition: Type.h:137
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:3592
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:1035
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:131
(Type)expr
Definition: SemaCast.cpp:50
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:293
bool isObjCLifetimeType() const
Returns true if objects of this type have lifetime semantics under ARC.
Definition: Type.cpp:4020
The cast method is not applicable.
Definition: SemaCast.cpp:33
A C-style cast.
Definition: Sema.h:9527
RecordDecl * getDefinition() const
Returns the RecordDecl that actually defines this struct/union/class.
Definition: Decl.h:3773
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:263
TryCastResult
Definition: SemaCast.cpp:32
static TryCastResult getCastAwayConstnessCastKind(CastAwayConstnessKind CACK, unsigned &DiagID)
Definition: SemaCast.cpp:654
void removeConst()
Definition: Type.h:256
bool isReferenceType() const
Definition: Type.h:6318
static CharUnits Zero()
Zero - Construct a CharUnits quantity of zero.
Definition: CharUnits.h:52
Ref_Incompatible - The two types are incompatible, so direct reference binding is not possible...
Definition: Sema.h:9907
Expr * getSubExpr()
Definition: Expr.h:3088
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:6236
bool isIntegralOrEnumerationType() const
Determine whether this type is an integral or enumeration type.
Definition: Type.h:6662
OverloadCandidateDisplayKind
Definition: Overload.h:65
An r-value expression (a pr-value in the C++11 taxonomy) produces a temporary value.
Definition: Specifiers.h:109
bool isInvalidType() const
Definition: DeclSpec.h:2442
bool isGLValue() const
Definition: Expr.h:254
static bool isValidCast(TryCastResult TCR)
Definition: SemaCast.cpp:41
bool isCompleteType(SourceLocation Loc, QualType T)
Definition: Sema.h:1708
An rvalue reference type, per C++11 [dcl.ref].
Definition: Type.h:2748
PtrTy get() const
Definition: Ownership.h:170
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:37
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:62
APValue Val
Val - This is the value the expression can be folded to.
Definition: Expr.h:575
Ref_Compatible - The two types are reference-compatible.
Definition: Sema.h:9913
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:407
const Type * getClass() const
Definition: Type.h:2800
bool isRValueReferenceType() const
Definition: Type.h:6326
CheckedConversionKind
The kind of conversion being performed.
Definition: Sema.h:9523
static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, bool CStyle, SourceRange OpRange, unsigned &msg, CastKind &Kind)
Definition: SemaCast.cpp:1982
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:7326
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:6082
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:3036
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:2743
const internal::VariadicDynCastAllOfMatcher< Stmt, CastExpr > castExpr
Matches any cast nodes of Clang&#39;s AST.
const LangOptions & getLangOpts() const
Definition: Sema.h:1281
ExprResult DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose=true)
Definition: SemaExpr.cpp:650
bool isScalarType() const
Definition: Type.h:6647
bool compatiblyIncludesObjCLifetime(Qualifiers other) const
Determines if these qualifiers compatibly include another set of qualifiers from the narrow perspecti...
Definition: Type.h:504
An ordinary object is located at an address in memory.
Definition: Specifiers.h:125
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:6095
static CastAwayConstnessKind unwrapCastAwayConstnessLevel(ASTContext &Context, QualType &T1, QualType &T2)
Unwrap one level of types for CastsAwayConstness.
Definition: SemaCast.cpp:481
bool hasConst() const
Definition: Type.h:254
bool isHalfType() const
Definition: Type.h:6564
Sema - This implements semantic analysis and AST building for C.
Definition: Sema.h:328
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1635
A functional-style cast.
Definition: Sema.h:9529
bool compatiblyIncludes(Qualifiers other) const
Determines if these qualifiers compatibly include another set.
Definition: Type.h:483
bool isComplexType() const
isComplexType() does not include complex integers (a GCC extension).
Definition: Type.cpp:481
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:1847
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:1669
bool isEnabled(llvm::StringRef Ext) const
Definition: OpenCLOptions.h:39
unsigned Offset
Definition: Format.cpp:1669
ASTRecordLayout - This class contains layout information for one RecordDecl, which is a struct/union/...
Definition: RecordLayout.h:38
An Objective-C property is a logical field of an Objective-C object which is read and written via Obj...
Definition: Specifiers.h:135
bool isEventT() const
Definition: Type.h:6468
This represents one expression.
Definition: Expr.h:108
static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType, SourceRange opRange, Expr *src, QualType destType, bool listInitialization)
Diagnose a failed cast.
Definition: SemaCast.cpp:412
QualType getPointeeType() const
Definition: Type.h:2704
ExprValueKind
The categorization of expression values, currently following the C++11 scheme.
Definition: Specifiers.h:106
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:2694
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:1620
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6829
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:35
Defines the clang::Preprocessor interface.
bool isNullPtrType() const
Definition: Type.h:6583
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:687
CXXRecordDecl * getDefinition() const
Definition: DeclCXX.h:768
Overload resolution succeeded.
Definition: Overload.h:53
ExprResult BuildCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind, TypeSourceInfo *Ty, Expr *E, SourceRange AngleBrackets, SourceRange Parens)
Definition: SemaCast.cpp:257
Stores token information for comparing actual tokens with predefined values.
Definition: Preprocessor.h:84
ExprResult CheckPlaceholderExpr(Expr *E)
Check for operands with placeholder types and complain if found.
Definition: SemaExpr.cpp:16827
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:1614
bool isConstructorInitialization() const
Determine whether this initialization is direct call to a constructor.
Definition: SemaInit.cpp:3364
ReferenceCompareResult
ReferenceCompareResult - Expresses the result of comparing two types (cv1 T1 and cv2 T2) to determine...
Definition: Sema.h:9904
bool RequireCompleteType(SourceLocation Loc, QualType T, TypeDiagnoser &Diagnoser)
Ensure that the type T is a complete type.
Definition: SemaType.cpp:7660
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:1866
QualType getType() const
Definition: Expr.h:130
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:1496
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:51
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:166
SourceLocation getEnd() const
Preprocessor & getPreprocessor() const
Definition: Sema.h:1287
Represents a GCC generic vector type.
Definition: Type.h:3178
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:1312
bool isUsable() const
Definition: Ownership.h:167
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:1395
The result type of a method or function.
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:235
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:276
unsigned getCVRQualifiers() const
Retrieve the set of CVR (const-volatile-restrict) qualifiers applied to this type.
Definition: Type.h:6115
ExprResult BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, SourceLocation RParenLoc, Expr *Op)
Definition: SemaCast.cpp:2779
bool isVoidPointerType() const
Definition: Type.cpp:469
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:6330
RecordDecl * getDecl() const
Definition: Type.h:4390
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:1384
CanQualType OverloadTy
Definition: ASTContext.h:1044
static CXXConstCastExpr * Create(const ASTContext &Context, QualType T, ExprValueKind VK, Expr *Op, TypeSourceInfo *WrittenTy, SourceLocation L, SourceLocation RParenLoc, SourceRange AngleBrackets)
Definition: ExprCXX.cpp:794
Kind
A reference to an overloaded function set, either an UnresolvedLookupExpr or an UnresolvedMemberExpr...
Definition: ExprCXX.h:2634
ActionResult - This structure is used while parsing/acting on expressions, stmts, etc...
Definition: Ownership.h:153
ASTContext & getASTContext() const
Definition: Sema.h:1288
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:4406
CastKind PrepareCastToObjCObjectPointer(ExprResult &E)
Prepare a conversion of the given expression to an ObjC object pointer type.
Definition: SemaExpr.cpp:6080
LangAS getAddressSpace() const
Return the address space of this type.
Definition: Type.h:6198
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:1350
static const FieldDecl * getTargetFieldForToUnionCast(QualType unionType, QualType opType)
Definition: Expr.cpp:1827
bool isIntegralType(const ASTContext &Ctx) const
Determine whether this type is an integral type.
Definition: Type.cpp:1781
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2048
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:234
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:65
TokenKind
Provides a simple uniform namespace for tokens from all C languages.
Definition: TokenKinds.h:24
Describes the kind of initialization being performed, along with location information for tokens rela...
const_cast
Definition: SemaCast.cpp:46
bool isMemberFunctionPointerType() const
Definition: Type.h:6341
bool isObjCObjectPointerType() const
Definition: Type.h:6403
bool isAnyPointerType() const
Definition: Type.h:6310
ImplicitCastExpr - Allows us to explicitly represent implicit type conversions, which have no direct ...
Definition: Expr.h:3153
bool isLValue() const
isLValue - True if this expression is an "l-value" according to the rules of the current language...
Definition: Expr.h:251
Overloading for initialization by constructor failed.
is AltiVec vector
Definition: Type.h:3185
Requests that all candidates be shown.
Definition: Overload.h:68
bool isAnyCharacterType() const
Determine whether this type is any of the built-in character types.
Definition: Type.cpp:1845
bool isVectorType() const
Definition: Type.h:6391
void removeObjCGCAttr()
Definition: Type.h:305
OverloadCandidateSet - A set of overload candidates, used in C++ overload resolution (C++ 13...
Definition: Overload.h:836
reinterpret_cast
Definition: SemaCast.cpp:48
static TryCastResult TryAddressSpaceCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, bool CStyle, unsigned &msg)
Definition: SemaCast.cpp:2287
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:2306
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:771
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:16735
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:6532
dynamic_cast
Definition: SemaCast.cpp:49
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.
EvalResult is a struct with detailed info about an evaluated expression.
Definition: Expr.h:573
void CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType, bool IsDereference, SourceRange Range)
Definition: SemaCast.cpp:1772
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:37
static std::string getAsString(SplitQualType split, const PrintingPolicy &Policy)
Definition: Type.h:972
const CXXRecordDecl * getParent() const
Returns the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2173
bool isBooleanType() const
Definition: Type.h:6675
ExprResult prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr)
Prepare SplattedExpr for a vector splat operation, adding implicit casts if necessary.
Definition: SemaExpr.cpp:6385
static void checkIntToPointerCast(bool CStyle, SourceLocation Loc, const Expr *SrcExpr, QualType DestType, Sema &Self)
Definition: SemaCast.cpp:1929
Requests that only viable candidates be shown.
Definition: Overload.h:71
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:2766
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:1822
static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType, ExprResult &Result)
Definition: SemaCast.cpp:1955
Expr * IgnoreParenImpCasts() LLVM_READONLY
Skip past any parentheses and implicit casts which might surround this expression until reaching a fi...
Definition: Expr.cpp:2723
ExprResult IgnoredValueConversions(Expr *E)
IgnoredValueConversions - Given that an expression&#39;s result is syntactically ignored, perform any conversions that are required.
SourceRange getSourceRange() const LLVM_READONLY
Get the full source range.
Definition: TypeLoc.h:150
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of structs/unions/cl...
Definition: Type.h:4380
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:336
bool isIntegerType() const
isIntegerType() does not include complex integers (a GCC extension).
Definition: Type.h:6592
ExprResult CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *CastExpr, CastKind &Kind)
Definition: SemaExpr.cpp:6418
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:1868
bool CheckDerivedToBaseConversion(QualType Derived, QualType Base, SourceLocation Loc, SourceRange Range, CXXCastPath *BasePath=nullptr, bool IgnoreAccess=false)
bool isFunctionType() const
Definition: Type.h:6302
bool isAddressSpaceSupersetOf(Qualifiers other) const
Returns true if this address space is a superset of the other one.
Definition: Type.h:470
MaterializeTemporaryExpr * CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary, bool BoundToLvalueReference)
Definition: SemaInit.cpp:7284
CXXBasePath & front()
Base for LValueReferenceType and RValueReferenceType.
Definition: Type.h:2683
bool hasSameType(QualType T1, QualType T2) const
Determine whether the given types T1 and T2 are equivalent.
Definition: ASTContext.h:2282
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:1254
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:91
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:2884
A bitfield object is a bitfield on a C or C++ record.
Definition: Specifiers.h:128
uint64_t getTypeSize(QualType T) const
Return the size of the specified (complete) type T, in bits.
Definition: ASTContext.h:2072
bool isObjCObjectType() const
Definition: Type.h:6407
QualType withCVRQualifiers(unsigned CVR) const
Definition: Type.h:831
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
Definition: ASTContext.h:2266
bool isLValueReferenceType() const
Definition: Type.h:6322
ExprResult BuildCXXFunctionalCastExpr(TypeSourceInfo *TInfo, QualType Type, SourceLocation LParenLoc, Expr *CastExpr, SourceLocation RParenLoc)
Definition: SemaCast.cpp:2805
TypeLoc getTypeLoc() const
Return the TypeLoc wrapper for the type source info.
Definition: TypeLoc.h:237
bool Failed() const
Determine whether the initialization sequence is invalid.
CallingConv getCallConv() const
Definition: Type.h:3633
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:6162
Represents a C++ struct/union/class.
Definition: DeclCXX.h:299
bool isMemberFunctionPointer() const
Returns true if the member type (i.e.
Definition: Type.h:2790
bool isVoidType() const
Definition: Type.h:6558
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:559
Qualifiers getQualifiers() const
Retrieve the set of qualifiers applied to this type.
Definition: Type.h:6109
QualType removeAddrSpaceQualType(QualType T) const
Remove any existing address space on the type and returns the type with qualifiers intact (or that&#39;s ...
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:128
This class is used for builtin types like &#39;int&#39;.
Definition: Type.h:2401
SourceRange getSourceRange() const LLVM_READONLY
SourceLocation tokens are not useful in isolation - they are low level value objects created/interpre...
Definition: Stmt.cpp:251
Defines the clang::TargetInfo interface.
bool isComplexIntegerType() const
Definition: Type.cpp:487
bool isMicrosoft() const
Is this ABI an MSVC-compatible ABI?
Definition: TargetCXXABI.h:153
unsigned getCVRQualifiers() const
Definition: Type.h:270
ExprResult ExprError()
Definition: Ownership.h:279
static Qualifiers fromCVRMask(unsigned CVR)
Definition: Type.h:230
bool hasVolatile() const
Definition: Type.h:259
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:2486
bool isDependentType() const
Whether this type is a dependent type, meaning that its definition somehow depends on a template para...
Definition: Type.h:2086
A reference to a declared variable, function, enum, etc.
Definition: Expr.h:1074
bool isIgnored(unsigned DiagID, SourceLocation Loc) const
Determine whether the diagnostic is known to be ignored.
Definition: Diagnostic.h:820
bool isUnion() const
Definition: Decl.h:3251
NestedNameSpecifierLoc getQualifierLoc() const
Fetches the nested-name qualifier with source-location information, if one was given.
Definition: ExprCXX.h:2755
bool isPointerType() const
Definition: Type.h:6306
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:56
static StringRef getNameForCallConv(CallingConv CC)
Definition: Type.cpp:2900
bool isFloatingType() const
Definition: Type.cpp:1943
A trivial tuple used to represent a source range.
ASTContext & Context
Definition: Sema.h:374
paths_iterator end()
APSInt & getInt()
Definition: APValue.h:257
Describes an entity that is being initialized.
bool isFunctionPointerType() const
Definition: Type.h:6330
SourceLocation getBegin() const
const LangOptions & getLangOpts() const
Definition: ASTContext.h:706
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:1868
CastType
Definition: SemaCast.cpp:45
QualType getPointeeType() const
Definition: Type.h:2786
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:850
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:123