Bug Summary

File:src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/lib/Sema/SemaCast.cpp
Warning:line 1358, column 14
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaCast.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model static -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/clang/libclangSema/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/libclangSema/obj/../include/clang/Sema -I /usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/include -I /usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/libclangSema/../include -I /usr/src/gnu/usr.bin/clang/libclangSema/obj -I /usr/src/gnu/usr.bin/clang/libclangSema/obj/../include -D NDEBUG -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D LLVM_PREFIX="/usr" -internal-isystem /usr/include/c++/v1 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/usr/src/gnu/usr.bin/clang/libclangSema/obj -ferror-limit 19 -fvisibility-inlines-hidden -fwrapv -stack-protector 2 -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c++ /usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/lib/Sema/SemaCast.cpp

/usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/lib/Sema/SemaCast.cpp

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
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/ASTStructuralEquivalence.h"
18#include "clang/AST/CXXInheritance.h"
19#include "clang/AST/ExprCXX.h"
20#include "clang/AST/ExprObjC.h"
21#include "clang/AST/RecordLayout.h"
22#include "clang/Basic/PartialDiagnostic.h"
23#include "clang/Basic/TargetInfo.h"
24#include "clang/Lex/Preprocessor.h"
25#include "clang/Sema/Initialization.h"
26#include "clang/Sema/SemaInternal.h"
27#include "llvm/ADT/SmallVector.h"
28#include <set>
29using namespace clang;
30
31
32
33enum TryCastResult {
34 TC_NotApplicable, ///< The cast method is not applicable.
35 TC_Success, ///< The cast method is appropriate and successful.
36 TC_Extension, ///< The cast method is appropriate and accepted as a
37 ///< language extension.
38 TC_Failed ///< The cast method is appropriate, but failed. A
39 ///< diagnostic has been emitted.
40};
41
42static bool isValidCast(TryCastResult TCR) {
43 return TCR == TC_Success || TCR == TC_Extension;
44}
45
46enum CastType {
47 CT_Const, ///< const_cast
48 CT_Static, ///< static_cast
49 CT_Reinterpret, ///< reinterpret_cast
50 CT_Dynamic, ///< dynamic_cast
51 CT_CStyle, ///< (Type)expr
52 CT_Functional, ///< Type(expr)
53 CT_Addrspace ///< addrspace_cast
54};
55
56namespace {
57 struct CastOperation {
58 CastOperation(Sema &S, QualType destType, ExprResult src)
59 : Self(S), SrcExpr(src), DestType(destType),
60 ResultType(destType.getNonLValueExprType(S.Context)),
61 ValueKind(Expr::getValueKindForType(destType)),
62 Kind(CK_Dependent), IsARCUnbridgedCast(false) {
63
64 // C++ [expr.type]/8.2.2:
65 // If a pr-value initially has the type cv-T, where T is a
66 // cv-unqualified non-class, non-array type, the type of the
67 // expression is adjusted to T prior to any further analysis.
68 if (!S.Context.getLangOpts().ObjC && !DestType->isRecordType() &&
69 !DestType->isArrayType()) {
70 DestType = DestType.getUnqualifiedType();
71 }
72
73 if (const BuiltinType *placeholder =
74 src.get()->getType()->getAsPlaceholderType()) {
75 PlaceholderKind = placeholder->getKind();
76 } else {
77 PlaceholderKind = (BuiltinType::Kind) 0;
78 }
79 }
80
81 Sema &Self;
82 ExprResult SrcExpr;
83 QualType DestType;
84 QualType ResultType;
85 ExprValueKind ValueKind;
86 CastKind Kind;
87 BuiltinType::Kind PlaceholderKind;
88 CXXCastPath BasePath;
89 bool IsARCUnbridgedCast;
90
91 SourceRange OpRange;
92 SourceRange DestRange;
93
94 // Top-level semantics-checking routines.
95 void CheckConstCast();
96 void CheckReinterpretCast();
97 void CheckStaticCast();
98 void CheckDynamicCast();
99 void CheckCXXCStyleCast(bool FunctionalCast, bool ListInitialization);
100 void CheckCStyleCast();
101 void CheckBuiltinBitCast();
102 void CheckAddrspaceCast();
103
104 void updatePartOfExplicitCastFlags(CastExpr *CE) {
105 // Walk down from the CE to the OrigSrcExpr, and mark all immediate
106 // ImplicitCastExpr's as being part of ExplicitCastExpr. The original CE
107 // (which is a ExplicitCastExpr), and the OrigSrcExpr are not touched.
108 for (; auto *ICE = dyn_cast<ImplicitCastExpr>(CE->getSubExpr()); CE = ICE)
109 ICE->setIsPartOfExplicitCast(true);
110 }
111
112 /// Complete an apparently-successful cast operation that yields
113 /// the given expression.
114 ExprResult complete(CastExpr *castExpr) {
115 // If this is an unbridged cast, wrap the result in an implicit
116 // cast that yields the unbridged-cast placeholder type.
117 if (IsARCUnbridgedCast) {
118 castExpr = ImplicitCastExpr::Create(
119 Self.Context, Self.Context.ARCUnbridgedCastTy, CK_Dependent,
120 castExpr, nullptr, castExpr->getValueKind(),
121 Self.CurFPFeatureOverrides());
122 }
123 updatePartOfExplicitCastFlags(castExpr);
124 return castExpr;
125 }
126
127 // Internal convenience methods.
128
129 /// Try to handle the given placeholder expression kind. Return
130 /// true if the source expression has the appropriate placeholder
131 /// kind. A placeholder can only be claimed once.
132 bool claimPlaceholder(BuiltinType::Kind K) {
133 if (PlaceholderKind != K) return false;
134
135 PlaceholderKind = (BuiltinType::Kind) 0;
136 return true;
137 }
138
139 bool isPlaceholder() const {
140 return PlaceholderKind != 0;
141 }
142 bool isPlaceholder(BuiltinType::Kind K) const {
143 return PlaceholderKind == K;
144 }
145
146 // Language specific cast restrictions for address spaces.
147 void checkAddressSpaceCast(QualType SrcType, QualType DestType);
148
149 void checkCastAlign() {
150 Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange);
151 }
152
153 void checkObjCConversion(Sema::CheckedConversionKind CCK) {
154 assert(Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())((void)0);
155
156 Expr *src = SrcExpr.get();
157 if (Self.CheckObjCConversion(OpRange, DestType, src, CCK) ==
158 Sema::ACR_unbridged)
159 IsARCUnbridgedCast = true;
160 SrcExpr = src;
161 }
162
163 /// Check for and handle non-overload placeholder expressions.
164 void checkNonOverloadPlaceholders() {
165 if (!isPlaceholder() || isPlaceholder(BuiltinType::Overload))
166 return;
167
168 SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
169 if (SrcExpr.isInvalid())
170 return;
171 PlaceholderKind = (BuiltinType::Kind) 0;
172 }
173 };
174
175 void CheckNoDeref(Sema &S, const QualType FromType, const QualType ToType,
176 SourceLocation OpLoc) {
177 if (const auto *PtrType = dyn_cast<PointerType>(FromType)) {
178 if (PtrType->getPointeeType()->hasAttr(attr::NoDeref)) {
179 if (const auto *DestType = dyn_cast<PointerType>(ToType)) {
180 if (!DestType->getPointeeType()->hasAttr(attr::NoDeref)) {
181 S.Diag(OpLoc, diag::warn_noderef_to_dereferenceable_pointer);
182 }
183 }
184 }
185 }
186 }
187
188 struct CheckNoDerefRAII {
189 CheckNoDerefRAII(CastOperation &Op) : Op(Op) {}
190 ~CheckNoDerefRAII() {
191 if (!Op.SrcExpr.isInvalid())
192 CheckNoDeref(Op.Self, Op.SrcExpr.get()->getType(), Op.ResultType,
193 Op.OpRange.getBegin());
194 }
195
196 CastOperation &Op;
197 };
198}
199
200static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
201 QualType DestType);
202
203// The Try functions attempt a specific way of casting. If they succeed, they
204// return TC_Success. If their way of casting is not appropriate for the given
205// arguments, they return TC_NotApplicable and *may* set diag to a diagnostic
206// to emit if no other way succeeds. If their way of casting is appropriate but
207// fails, they return TC_Failed and *must* set diag; they can set it to 0 if
208// they emit a specialized diagnostic.
209// All diagnostics returned by these functions must expect the same three
210// arguments:
211// %0: Cast Type (a value from the CastType enumeration)
212// %1: Source Type
213// %2: Destination Type
214static TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
215 QualType DestType, bool CStyle,
216 CastKind &Kind,
217 CXXCastPath &BasePath,
218 unsigned &msg);
219static TryCastResult TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr,
220 QualType DestType, bool CStyle,
221 SourceRange OpRange,
222 unsigned &msg,
223 CastKind &Kind,
224 CXXCastPath &BasePath);
225static TryCastResult TryStaticPointerDowncast(Sema &Self, QualType SrcType,
226 QualType DestType, bool CStyle,
227 SourceRange OpRange,
228 unsigned &msg,
229 CastKind &Kind,
230 CXXCastPath &BasePath);
231static TryCastResult TryStaticDowncast(Sema &Self, CanQualType SrcType,
232 CanQualType DestType, bool CStyle,
233 SourceRange OpRange,
234 QualType OrigSrcType,
235 QualType OrigDestType, unsigned &msg,
236 CastKind &Kind,
237 CXXCastPath &BasePath);
238static TryCastResult TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr,
239 QualType SrcType,
240 QualType DestType,bool CStyle,
241 SourceRange OpRange,
242 unsigned &msg,
243 CastKind &Kind,
244 CXXCastPath &BasePath);
245
246static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr,
247 QualType DestType,
248 Sema::CheckedConversionKind CCK,
249 SourceRange OpRange,
250 unsigned &msg, CastKind &Kind,
251 bool ListInitialization);
252static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
253 QualType DestType,
254 Sema::CheckedConversionKind CCK,
255 SourceRange OpRange,
256 unsigned &msg, CastKind &Kind,
257 CXXCastPath &BasePath,
258 bool ListInitialization);
259static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
260 QualType DestType, bool CStyle,
261 unsigned &msg);
262static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
263 QualType DestType, bool CStyle,
264 SourceRange OpRange, unsigned &msg,
265 CastKind &Kind);
266static TryCastResult TryAddressSpaceCast(Sema &Self, ExprResult &SrcExpr,
267 QualType DestType, bool CStyle,
268 unsigned &msg, CastKind &Kind);
269
270/// ActOnCXXNamedCast - Parse
271/// {dynamic,static,reinterpret,const,addrspace}_cast's.
272ExprResult
273Sema::ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
274 SourceLocation LAngleBracketLoc, Declarator &D,
275 SourceLocation RAngleBracketLoc,
276 SourceLocation LParenLoc, Expr *E,
277 SourceLocation RParenLoc) {
278
279 assert(!D.isInvalidType())((void)0);
280
281 TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, E->getType());
282 if (D.isInvalidType())
1
Taking false branch
283 return ExprError();
284
285 if (getLangOpts().CPlusPlus) {
2
Assuming field 'CPlusPlus' is 0
3
Taking false branch
286 // Check that there are no default arguments (C++ only).
287 CheckExtraCXXDefaultArguments(D);
288 }
289
290 return BuildCXXNamedCast(OpLoc, Kind, TInfo, E,
4
Calling 'Sema::BuildCXXNamedCast'
291 SourceRange(LAngleBracketLoc, RAngleBracketLoc),
292 SourceRange(LParenLoc, RParenLoc));
293}
294
295ExprResult
296Sema::BuildCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
297 TypeSourceInfo *DestTInfo, Expr *E,
298 SourceRange AngleBrackets, SourceRange Parens) {
299 ExprResult Ex = E;
300 QualType DestType = DestTInfo->getType();
301
302 // If the type is dependent, we won't do the semantic analysis now.
303 bool TypeDependent =
304 DestType->isDependentType() || Ex.get()->isTypeDependent();
5
Assuming the condition is false
305
306 CastOperation Op(*this, DestType, E);
307 Op.OpRange = SourceRange(OpLoc, Parens.getEnd());
308 Op.DestRange = AngleBrackets;
309
310 switch (Kind) {
6
Control jumps to 'case kw_static_cast:' at line 366
311 default: llvm_unreachable("Unknown C++ cast!")__builtin_unreachable();
312
313 case tok::kw_addrspace_cast:
314 if (!TypeDependent) {
315 Op.CheckAddrspaceCast();
316 if (Op.SrcExpr.isInvalid())
317 return ExprError();
318 }
319 return Op.complete(CXXAddrspaceCastExpr::Create(
320 Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
321 DestTInfo, OpLoc, Parens.getEnd(), AngleBrackets));
322
323 case tok::kw_const_cast:
324 if (!TypeDependent) {
325 Op.CheckConstCast();
326 if (Op.SrcExpr.isInvalid())
327 return ExprError();
328 DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
329 }
330 return Op.complete(CXXConstCastExpr::Create(Context, Op.ResultType,
331 Op.ValueKind, Op.SrcExpr.get(), DestTInfo,
332 OpLoc, Parens.getEnd(),
333 AngleBrackets));
334
335 case tok::kw_dynamic_cast: {
336 // dynamic_cast is not supported in C++ for OpenCL.
337 if (getLangOpts().OpenCLCPlusPlus) {
338 return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
339 << "dynamic_cast");
340 }
341
342 if (!TypeDependent) {
343 Op.CheckDynamicCast();
344 if (Op.SrcExpr.isInvalid())
345 return ExprError();
346 }
347 return Op.complete(CXXDynamicCastExpr::Create(Context, Op.ResultType,
348 Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
349 &Op.BasePath, DestTInfo,
350 OpLoc, Parens.getEnd(),
351 AngleBrackets));
352 }
353 case tok::kw_reinterpret_cast: {
354 if (!TypeDependent) {
355 Op.CheckReinterpretCast();
356 if (Op.SrcExpr.isInvalid())
357 return ExprError();
358 DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
359 }
360 return Op.complete(CXXReinterpretCastExpr::Create(Context, Op.ResultType,
361 Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
362 nullptr, DestTInfo, OpLoc,
363 Parens.getEnd(),
364 AngleBrackets));
365 }
366 case tok::kw_static_cast: {
367 if (!TypeDependent) {
7
Assuming 'TypeDependent' is false
8
Taking true branch
368 Op.CheckStaticCast();
9
Calling 'CastOperation::CheckStaticCast'
369 if (Op.SrcExpr.isInvalid())
370 return ExprError();
371 DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
372 }
373
374 return Op.complete(CXXStaticCastExpr::Create(
375 Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
376 &Op.BasePath, DestTInfo, CurFPFeatureOverrides(), OpLoc,
377 Parens.getEnd(), AngleBrackets));
378 }
379 }
380}
381
382ExprResult Sema::ActOnBuiltinBitCastExpr(SourceLocation KWLoc, Declarator &D,
383 ExprResult Operand,
384 SourceLocation RParenLoc) {
385 assert(!D.isInvalidType())((void)0);
386
387 TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, Operand.get()->getType());
388 if (D.isInvalidType())
389 return ExprError();
390
391 return BuildBuiltinBitCastExpr(KWLoc, TInfo, Operand.get(), RParenLoc);
392}
393
394ExprResult Sema::BuildBuiltinBitCastExpr(SourceLocation KWLoc,
395 TypeSourceInfo *TSI, Expr *Operand,
396 SourceLocation RParenLoc) {
397 CastOperation Op(*this, TSI->getType(), Operand);
398 Op.OpRange = SourceRange(KWLoc, RParenLoc);
399 TypeLoc TL = TSI->getTypeLoc();
400 Op.DestRange = SourceRange(TL.getBeginLoc(), TL.getEndLoc());
401
402 if (!Operand->isTypeDependent() && !TSI->getType()->isDependentType()) {
403 Op.CheckBuiltinBitCast();
404 if (Op.SrcExpr.isInvalid())
405 return ExprError();
406 }
407
408 BuiltinBitCastExpr *BCE =
409 new (Context) BuiltinBitCastExpr(Op.ResultType, Op.ValueKind, Op.Kind,
410 Op.SrcExpr.get(), TSI, KWLoc, RParenLoc);
411 return Op.complete(BCE);
412}
413
414/// Try to diagnose a failed overloaded cast. Returns true if
415/// diagnostics were emitted.
416static bool tryDiagnoseOverloadedCast(Sema &S, CastType CT,
417 SourceRange range, Expr *src,
418 QualType destType,
419 bool listInitialization) {
420 switch (CT) {
421 // These cast kinds don't consider user-defined conversions.
422 case CT_Const:
423 case CT_Reinterpret:
424 case CT_Dynamic:
425 case CT_Addrspace:
426 return false;
427
428 // These do.
429 case CT_Static:
430 case CT_CStyle:
431 case CT_Functional:
432 break;
433 }
434
435 QualType srcType = src->getType();
436 if (!destType->isRecordType() && !srcType->isRecordType())
437 return false;
438
439 InitializedEntity entity = InitializedEntity::InitializeTemporary(destType);
440 InitializationKind initKind
441 = (CT == CT_CStyle)? InitializationKind::CreateCStyleCast(range.getBegin(),
442 range, listInitialization)
443 : (CT == CT_Functional)? InitializationKind::CreateFunctionalCast(range,
444 listInitialization)
445 : InitializationKind::CreateCast(/*type range?*/ range);
446 InitializationSequence sequence(S, entity, initKind, src);
447
448 assert(sequence.Failed() && "initialization succeeded on second try?")((void)0);
449 switch (sequence.getFailureKind()) {
450 default: return false;
451
452 case InitializationSequence::FK_ConstructorOverloadFailed:
453 case InitializationSequence::FK_UserConversionOverloadFailed:
454 break;
455 }
456
457 OverloadCandidateSet &candidates = sequence.getFailedCandidateSet();
458
459 unsigned msg = 0;
460 OverloadCandidateDisplayKind howManyCandidates = OCD_AllCandidates;
461
462 switch (sequence.getFailedOverloadResult()) {
463 case OR_Success: llvm_unreachable("successful failed overload")__builtin_unreachable();
464 case OR_No_Viable_Function:
465 if (candidates.empty())
466 msg = diag::err_ovl_no_conversion_in_cast;
467 else
468 msg = diag::err_ovl_no_viable_conversion_in_cast;
469 howManyCandidates = OCD_AllCandidates;
470 break;
471
472 case OR_Ambiguous:
473 msg = diag::err_ovl_ambiguous_conversion_in_cast;
474 howManyCandidates = OCD_AmbiguousCandidates;
475 break;
476
477 case OR_Deleted:
478 msg = diag::err_ovl_deleted_conversion_in_cast;
479 howManyCandidates = OCD_ViableCandidates;
480 break;
481 }
482
483 candidates.NoteCandidates(
484 PartialDiagnosticAt(range.getBegin(),
485 S.PDiag(msg) << CT << srcType << destType << range
486 << src->getSourceRange()),
487 S, howManyCandidates, src);
488
489 return true;
490}
491
492/// Diagnose a failed cast.
493static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType,
494 SourceRange opRange, Expr *src, QualType destType,
495 bool listInitialization) {
496 if (msg == diag::err_bad_cxx_cast_generic &&
497 tryDiagnoseOverloadedCast(S, castType, opRange, src, destType,
498 listInitialization))
499 return;
500
501 S.Diag(opRange.getBegin(), msg) << castType
502 << src->getType() << destType << opRange << src->getSourceRange();
503
504 // Detect if both types are (ptr to) class, and note any incompleteness.
505 int DifferentPtrness = 0;
506 QualType From = destType;
507 if (auto Ptr = From->getAs<PointerType>()) {
508 From = Ptr->getPointeeType();
509 DifferentPtrness++;
510 }
511 QualType To = src->getType();
512 if (auto Ptr = To->getAs<PointerType>()) {
513 To = Ptr->getPointeeType();
514 DifferentPtrness--;
515 }
516 if (!DifferentPtrness) {
517 auto RecFrom = From->getAs<RecordType>();
518 auto RecTo = To->getAs<RecordType>();
519 if (RecFrom && RecTo) {
520 auto DeclFrom = RecFrom->getAsCXXRecordDecl();
521 if (!DeclFrom->isCompleteDefinition())
522 S.Diag(DeclFrom->getLocation(), diag::note_type_incomplete) << DeclFrom;
523 auto DeclTo = RecTo->getAsCXXRecordDecl();
524 if (!DeclTo->isCompleteDefinition())
525 S.Diag(DeclTo->getLocation(), diag::note_type_incomplete) << DeclTo;
526 }
527 }
528}
529
530namespace {
531/// The kind of unwrapping we did when determining whether a conversion casts
532/// away constness.
533enum CastAwayConstnessKind {
534 /// The conversion does not cast away constness.
535 CACK_None = 0,
536 /// We unwrapped similar types.
537 CACK_Similar = 1,
538 /// We unwrapped dissimilar types with similar representations (eg, a pointer
539 /// versus an Objective-C object pointer).
540 CACK_SimilarKind = 2,
541 /// We unwrapped representationally-unrelated types, such as a pointer versus
542 /// a pointer-to-member.
543 CACK_Incoherent = 3,
544};
545}
546
547/// Unwrap one level of types for CastsAwayConstness.
548///
549/// Like Sema::UnwrapSimilarTypes, this removes one level of indirection from
550/// both types, provided that they're both pointer-like or array-like. Unlike
551/// the Sema function, doesn't care if the unwrapped pieces are related.
552///
553/// This function may remove additional levels as necessary for correctness:
554/// the resulting T1 is unwrapped sufficiently that it is never an array type,
555/// so that its qualifiers can be directly compared to those of T2 (which will
556/// have the combined set of qualifiers from all indermediate levels of T2),
557/// as (effectively) required by [expr.const.cast]p7 replacing T1's qualifiers
558/// with those from T2.
559static CastAwayConstnessKind
560unwrapCastAwayConstnessLevel(ASTContext &Context, QualType &T1, QualType &T2) {
561 enum { None, Ptr, MemPtr, BlockPtr, Array };
562 auto Classify = [](QualType T) {
563 if (T->isAnyPointerType()) return Ptr;
564 if (T->isMemberPointerType()) return MemPtr;
565 if (T->isBlockPointerType()) return BlockPtr;
566 // We somewhat-arbitrarily don't look through VLA types here. This is at
567 // least consistent with the behavior of UnwrapSimilarTypes.
568 if (T->isConstantArrayType() || T->isIncompleteArrayType()) return Array;
569 return None;
570 };
571
572 auto Unwrap = [&](QualType T) {
573 if (auto *AT = Context.getAsArrayType(T))
574 return AT->getElementType();
575 return T->getPointeeType();
576 };
577
578 CastAwayConstnessKind Kind;
579
580 if (T2->isReferenceType()) {
581 // Special case: if the destination type is a reference type, unwrap it as
582 // the first level. (The source will have been an lvalue expression in this
583 // case, so there is no corresponding "reference to" in T1 to remove.) This
584 // simulates removing a "pointer to" from both sides.
585 T2 = T2->getPointeeType();
586 Kind = CastAwayConstnessKind::CACK_Similar;
587 } else if (Context.UnwrapSimilarTypes(T1, T2)) {
588 Kind = CastAwayConstnessKind::CACK_Similar;
589 } else {
590 // Try unwrapping mismatching levels.
591 int T1Class = Classify(T1);
592 if (T1Class == None)
593 return CastAwayConstnessKind::CACK_None;
594
595 int T2Class = Classify(T2);
596 if (T2Class == None)
597 return CastAwayConstnessKind::CACK_None;
598
599 T1 = Unwrap(T1);
600 T2 = Unwrap(T2);
601 Kind = T1Class == T2Class ? CastAwayConstnessKind::CACK_SimilarKind
602 : CastAwayConstnessKind::CACK_Incoherent;
603 }
604
605 // We've unwrapped at least one level. If the resulting T1 is a (possibly
606 // multidimensional) array type, any qualifier on any matching layer of
607 // T2 is considered to correspond to T1. Decompose down to the element
608 // type of T1 so that we can compare properly.
609 while (true) {
610 Context.UnwrapSimilarArrayTypes(T1, T2);
611
612 if (Classify(T1) != Array)
613 break;
614
615 auto T2Class = Classify(T2);
616 if (T2Class == None)
617 break;
618
619 if (T2Class != Array)
620 Kind = CastAwayConstnessKind::CACK_Incoherent;
621 else if (Kind != CastAwayConstnessKind::CACK_Incoherent)
622 Kind = CastAwayConstnessKind::CACK_SimilarKind;
623
624 T1 = Unwrap(T1);
625 T2 = Unwrap(T2).withCVRQualifiers(T2.getCVRQualifiers());
626 }
627
628 return Kind;
629}
630
631/// Check if the pointer conversion from SrcType to DestType casts away
632/// constness as defined in C++ [expr.const.cast]. This is used by the cast
633/// checkers. Both arguments must denote pointer (possibly to member) types.
634///
635/// \param CheckCVR Whether to check for const/volatile/restrict qualifiers.
636/// \param CheckObjCLifetime Whether to check Objective-C lifetime qualifiers.
637static CastAwayConstnessKind
638CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType,
639 bool CheckCVR, bool CheckObjCLifetime,
640 QualType *TheOffendingSrcType = nullptr,
641 QualType *TheOffendingDestType = nullptr,
642 Qualifiers *CastAwayQualifiers = nullptr) {
643 // If the only checking we care about is for Objective-C lifetime qualifiers,
644 // and we're not in ObjC mode, there's nothing to check.
645 if (!CheckCVR && CheckObjCLifetime && !Self.Context.getLangOpts().ObjC)
646 return CastAwayConstnessKind::CACK_None;
647
648 if (!DestType->isReferenceType()) {
649 assert((SrcType->isAnyPointerType() || SrcType->isMemberPointerType() ||((void)0)
650 SrcType->isBlockPointerType()) &&((void)0)
651 "Source type is not pointer or pointer to member.")((void)0);
652 assert((DestType->isAnyPointerType() || DestType->isMemberPointerType() ||((void)0)
653 DestType->isBlockPointerType()) &&((void)0)
654 "Destination type is not pointer or pointer to member.")((void)0);
655 }
656
657 QualType UnwrappedSrcType = Self.Context.getCanonicalType(SrcType),
658 UnwrappedDestType = Self.Context.getCanonicalType(DestType);
659
660 // Find the qualifiers. We only care about cvr-qualifiers for the
661 // purpose of this check, because other qualifiers (address spaces,
662 // Objective-C GC, etc.) are part of the type's identity.
663 QualType PrevUnwrappedSrcType = UnwrappedSrcType;
664 QualType PrevUnwrappedDestType = UnwrappedDestType;
665 auto WorstKind = CastAwayConstnessKind::CACK_Similar;
666 bool AllConstSoFar = true;
667 while (auto Kind = unwrapCastAwayConstnessLevel(
668 Self.Context, UnwrappedSrcType, UnwrappedDestType)) {
669 // Track the worst kind of unwrap we needed to do before we found a
670 // problem.
671 if (Kind > WorstKind)
672 WorstKind = Kind;
673
674 // Determine the relevant qualifiers at this level.
675 Qualifiers SrcQuals, DestQuals;
676 Self.Context.getUnqualifiedArrayType(UnwrappedSrcType, SrcQuals);
677 Self.Context.getUnqualifiedArrayType(UnwrappedDestType, DestQuals);
678
679 // We do not meaningfully track object const-ness of Objective-C object
680 // types. Remove const from the source type if either the source or
681 // the destination is an Objective-C object type.
682 if (UnwrappedSrcType->isObjCObjectType() ||
683 UnwrappedDestType->isObjCObjectType())
684 SrcQuals.removeConst();
685
686 if (CheckCVR) {
687 Qualifiers SrcCvrQuals =
688 Qualifiers::fromCVRMask(SrcQuals.getCVRQualifiers());
689 Qualifiers DestCvrQuals =
690 Qualifiers::fromCVRMask(DestQuals.getCVRQualifiers());
691
692 if (SrcCvrQuals != DestCvrQuals) {
693 if (CastAwayQualifiers)
694 *CastAwayQualifiers = SrcCvrQuals - DestCvrQuals;
695
696 // If we removed a cvr-qualifier, this is casting away 'constness'.
697 if (!DestCvrQuals.compatiblyIncludes(SrcCvrQuals)) {
698 if (TheOffendingSrcType)
699 *TheOffendingSrcType = PrevUnwrappedSrcType;
700 if (TheOffendingDestType)
701 *TheOffendingDestType = PrevUnwrappedDestType;
702 return WorstKind;
703 }
704
705 // If any prior level was not 'const', this is also casting away
706 // 'constness'. We noted the outermost type missing a 'const' already.
707 if (!AllConstSoFar)
708 return WorstKind;
709 }
710 }
711
712 if (CheckObjCLifetime &&
713 !DestQuals.compatiblyIncludesObjCLifetime(SrcQuals))
714 return WorstKind;
715
716 // If we found our first non-const-qualified type, this may be the place
717 // where things start to go wrong.
718 if (AllConstSoFar && !DestQuals.hasConst()) {
719 AllConstSoFar = false;
720 if (TheOffendingSrcType)
721 *TheOffendingSrcType = PrevUnwrappedSrcType;
722 if (TheOffendingDestType)
723 *TheOffendingDestType = PrevUnwrappedDestType;
724 }
725
726 PrevUnwrappedSrcType = UnwrappedSrcType;
727 PrevUnwrappedDestType = UnwrappedDestType;
728 }
729
730 return CastAwayConstnessKind::CACK_None;
731}
732
733static TryCastResult getCastAwayConstnessCastKind(CastAwayConstnessKind CACK,
734 unsigned &DiagID) {
735 switch (CACK) {
736 case CastAwayConstnessKind::CACK_None:
737 llvm_unreachable("did not cast away constness")__builtin_unreachable();
738
739 case CastAwayConstnessKind::CACK_Similar:
740 // FIXME: Accept these as an extension too?
741 case CastAwayConstnessKind::CACK_SimilarKind:
742 DiagID = diag::err_bad_cxx_cast_qualifiers_away;
743 return TC_Failed;
744
745 case CastAwayConstnessKind::CACK_Incoherent:
746 DiagID = diag::ext_bad_cxx_cast_qualifiers_away_incoherent;
747 return TC_Extension;
748 }
749
750 llvm_unreachable("unexpected cast away constness kind")__builtin_unreachable();
751}
752
753/// CheckDynamicCast - Check that a dynamic_cast\<DestType\>(SrcExpr) is valid.
754/// Refer to C++ 5.2.7 for details. Dynamic casts are used mostly for runtime-
755/// checked downcasts in class hierarchies.
756void CastOperation::CheckDynamicCast() {
757 CheckNoDerefRAII NoderefCheck(*this);
758
759 if (ValueKind == VK_PRValue)
760 SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
761 else if (isPlaceholder())
762 SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
763 if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
764 return;
765
766 QualType OrigSrcType = SrcExpr.get()->getType();
767 QualType DestType = Self.Context.getCanonicalType(this->DestType);
768
769 // C++ 5.2.7p1: T shall be a pointer or reference to a complete class type,
770 // or "pointer to cv void".
771
772 QualType DestPointee;
773 const PointerType *DestPointer = DestType->getAs<PointerType>();
774 const ReferenceType *DestReference = nullptr;
775 if (DestPointer) {
776 DestPointee = DestPointer->getPointeeType();
777 } else if ((DestReference = DestType->getAs<ReferenceType>())) {
778 DestPointee = DestReference->getPointeeType();
779 } else {
780 Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ref_or_ptr)
781 << this->DestType << DestRange;
782 SrcExpr = ExprError();
783 return;
784 }
785
786 const RecordType *DestRecord = DestPointee->getAs<RecordType>();
787 if (DestPointee->isVoidType()) {
788 assert(DestPointer && "Reference to void is not possible")((void)0);
789 } else if (DestRecord) {
790 if (Self.RequireCompleteType(OpRange.getBegin(), DestPointee,
791 diag::err_bad_cast_incomplete,
792 DestRange)) {
793 SrcExpr = ExprError();
794 return;
795 }
796 } else {
797 Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
798 << DestPointee.getUnqualifiedType() << DestRange;
799 SrcExpr = ExprError();
800 return;
801 }
802
803 // C++0x 5.2.7p2: If T is a pointer type, v shall be an rvalue of a pointer to
804 // complete class type, [...]. If T is an lvalue reference type, v shall be
805 // an lvalue of a complete class type, [...]. If T is an rvalue reference
806 // type, v shall be an expression having a complete class type, [...]
807 QualType SrcType = Self.Context.getCanonicalType(OrigSrcType);
808 QualType SrcPointee;
809 if (DestPointer) {
810 if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
811 SrcPointee = SrcPointer->getPointeeType();
812 } else {
813 Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ptr)
814 << OrigSrcType << this->DestType << SrcExpr.get()->getSourceRange();
815 SrcExpr = ExprError();
816 return;
817 }
818 } else if (DestReference->isLValueReferenceType()) {
819 if (!SrcExpr.get()->isLValue()) {
820 Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
821 << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
822 }
823 SrcPointee = SrcType;
824 } else {
825 // If we're dynamic_casting from a prvalue to an rvalue reference, we need
826 // to materialize the prvalue before we bind the reference to it.
827 if (SrcExpr.get()->isPRValue())
828 SrcExpr = Self.CreateMaterializeTemporaryExpr(
829 SrcType, SrcExpr.get(), /*IsLValueReference*/ false);
830 SrcPointee = SrcType;
831 }
832
833 const RecordType *SrcRecord = SrcPointee->getAs<RecordType>();
834 if (SrcRecord) {
835 if (Self.RequireCompleteType(OpRange.getBegin(), SrcPointee,
836 diag::err_bad_cast_incomplete,
837 SrcExpr.get())) {
838 SrcExpr = ExprError();
839 return;
840 }
841 } else {
842 Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
843 << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
844 SrcExpr = ExprError();
845 return;
846 }
847
848 assert((DestPointer || DestReference) &&((void)0)
849 "Bad destination non-ptr/ref slipped through.")((void)0);
850 assert((DestRecord || DestPointee->isVoidType()) &&((void)0)
851 "Bad destination pointee slipped through.")((void)0);
852 assert(SrcRecord && "Bad source pointee slipped through.")((void)0);
853
854 // C++ 5.2.7p1: The dynamic_cast operator shall not cast away constness.
855 if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
856 Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_qualifiers_away)
857 << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
858 SrcExpr = ExprError();
859 return;
860 }
861
862 // C++ 5.2.7p3: If the type of v is the same as the required result type,
863 // [except for cv].
864 if (DestRecord == SrcRecord) {
865 Kind = CK_NoOp;
866 return;
867 }
868
869 // C++ 5.2.7p5
870 // Upcasts are resolved statically.
871 if (DestRecord &&
872 Self.IsDerivedFrom(OpRange.getBegin(), SrcPointee, DestPointee)) {
873 if (Self.CheckDerivedToBaseConversion(SrcPointee, DestPointee,
874 OpRange.getBegin(), OpRange,
875 &BasePath)) {
876 SrcExpr = ExprError();
877 return;
878 }
879
880 Kind = CK_DerivedToBase;
881 return;
882 }
883
884 // C++ 5.2.7p6: Otherwise, v shall be [polymorphic].
885 const RecordDecl *SrcDecl = SrcRecord->getDecl()->getDefinition();
886 assert(SrcDecl && "Definition missing")((void)0);
887 if (!cast<CXXRecordDecl>(SrcDecl)->isPolymorphic()) {
888 Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_polymorphic)
889 << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
890 SrcExpr = ExprError();
891 }
892
893 // dynamic_cast is not available with -fno-rtti.
894 // As an exception, dynamic_cast to void* is available because it doesn't
895 // use RTTI.
896 if (!Self.getLangOpts().RTTI && !DestPointee->isVoidType()) {
897 Self.Diag(OpRange.getBegin(), diag::err_no_dynamic_cast_with_fno_rtti);
898 SrcExpr = ExprError();
899 return;
900 }
901
902 // Warns when dynamic_cast is used with RTTI data disabled.
903 if (!Self.getLangOpts().RTTIData) {
904 bool MicrosoftABI =
905 Self.getASTContext().getTargetInfo().getCXXABI().isMicrosoft();
906 bool isClangCL = Self.getDiagnostics().getDiagnosticOptions().getFormat() ==
907 DiagnosticOptions::MSVC;
908 if (MicrosoftABI || !DestPointee->isVoidType())
909 Self.Diag(OpRange.getBegin(),
910 diag::warn_no_dynamic_cast_with_rtti_disabled)
911 << isClangCL;
912 }
913
914 // Done. Everything else is run-time checks.
915 Kind = CK_Dynamic;
916}
917
918/// CheckConstCast - Check that a const_cast\<DestType\>(SrcExpr) is valid.
919/// Refer to C++ 5.2.11 for details. const_cast is typically used in code
920/// like this:
921/// const char *str = "literal";
922/// legacy_function(const_cast\<char*\>(str));
923void CastOperation::CheckConstCast() {
924 CheckNoDerefRAII NoderefCheck(*this);
925
926 if (ValueKind == VK_PRValue)
927 SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
928 else if (isPlaceholder())
929 SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
930 if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
931 return;
932
933 unsigned msg = diag::err_bad_cxx_cast_generic;
934 auto TCR = TryConstCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg);
935 if (TCR != TC_Success && msg != 0) {
936 Self.Diag(OpRange.getBegin(), msg) << CT_Const
937 << SrcExpr.get()->getType() << DestType << OpRange;
938 }
939 if (!isValidCast(TCR))
940 SrcExpr = ExprError();
941}
942
943void CastOperation::CheckAddrspaceCast() {
944 unsigned msg = diag::err_bad_cxx_cast_generic;
945 auto TCR =
946 TryAddressSpaceCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg, Kind);
947 if (TCR != TC_Success && msg != 0) {
948 Self.Diag(OpRange.getBegin(), msg)
949 << CT_Addrspace << SrcExpr.get()->getType() << DestType << OpRange;
950 }
951 if (!isValidCast(TCR))
952 SrcExpr = ExprError();
953}
954
955/// Check that a reinterpret_cast\<DestType\>(SrcExpr) is not used as upcast
956/// or downcast between respective pointers or references.
957static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
958 QualType DestType,
959 SourceRange OpRange) {
960 QualType SrcType = SrcExpr->getType();
961 // When casting from pointer or reference, get pointee type; use original
962 // type otherwise.
963 const CXXRecordDecl *SrcPointeeRD = SrcType->getPointeeCXXRecordDecl();
964 const CXXRecordDecl *SrcRD =
965 SrcPointeeRD ? SrcPointeeRD : SrcType->getAsCXXRecordDecl();
966
967 // Examining subobjects for records is only possible if the complete and
968 // valid definition is available. Also, template instantiation is not
969 // allowed here.
970 if (!SrcRD || !SrcRD->isCompleteDefinition() || SrcRD->isInvalidDecl())
971 return;
972
973 const CXXRecordDecl *DestRD = DestType->getPointeeCXXRecordDecl();
974
975 if (!DestRD || !DestRD->isCompleteDefinition() || DestRD->isInvalidDecl())
976 return;
977
978 enum {
979 ReinterpretUpcast,
980 ReinterpretDowncast
981 } ReinterpretKind;
982
983 CXXBasePaths BasePaths;
984
985 if (SrcRD->isDerivedFrom(DestRD, BasePaths))
986 ReinterpretKind = ReinterpretUpcast;
987 else if (DestRD->isDerivedFrom(SrcRD, BasePaths))
988 ReinterpretKind = ReinterpretDowncast;
989 else
990 return;
991
992 bool VirtualBase = true;
993 bool NonZeroOffset = false;
994 for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(),
995 E = BasePaths.end();
996 I != E; ++I) {
997 const CXXBasePath &Path = *I;
998 CharUnits Offset = CharUnits::Zero();
999 bool IsVirtual = false;
1000 for (CXXBasePath::const_iterator IElem = Path.begin(), EElem = Path.end();
1001 IElem != EElem; ++IElem) {
1002 IsVirtual = IElem->Base->isVirtual();
1003 if (IsVirtual)
1004 break;
1005 const CXXRecordDecl *BaseRD = IElem->Base->getType()->getAsCXXRecordDecl();
1006 assert(BaseRD && "Base type should be a valid unqualified class type")((void)0);
1007 // Don't check if any base has invalid declaration or has no definition
1008 // since it has no layout info.
1009 const CXXRecordDecl *Class = IElem->Class,
1010 *ClassDefinition = Class->getDefinition();
1011 if (Class->isInvalidDecl() || !ClassDefinition ||
1012 !ClassDefinition->isCompleteDefinition())
1013 return;
1014
1015 const ASTRecordLayout &DerivedLayout =
1016 Self.Context.getASTRecordLayout(Class);
1017 Offset += DerivedLayout.getBaseClassOffset(BaseRD);
1018 }
1019 if (!IsVirtual) {
1020 // Don't warn if any path is a non-virtually derived base at offset zero.
1021 if (Offset.isZero())
1022 return;
1023 // Offset makes sense only for non-virtual bases.
1024 else
1025 NonZeroOffset = true;
1026 }
1027 VirtualBase = VirtualBase && IsVirtual;
1028 }
1029
1030 (void) NonZeroOffset; // Silence set but not used warning.
1031 assert((VirtualBase || NonZeroOffset) &&((void)0)
1032 "Should have returned if has non-virtual base with zero offset")((void)0);
1033
1034 QualType BaseType =
1035 ReinterpretKind == ReinterpretUpcast? DestType : SrcType;
1036 QualType DerivedType =
1037 ReinterpretKind == ReinterpretUpcast? SrcType : DestType;
1038
1039 SourceLocation BeginLoc = OpRange.getBegin();
1040 Self.Diag(BeginLoc, diag::warn_reinterpret_different_from_static)
1041 << DerivedType << BaseType << !VirtualBase << int(ReinterpretKind)
1042 << OpRange;
1043 Self.Diag(BeginLoc, diag::note_reinterpret_updowncast_use_static)
1044 << int(ReinterpretKind)
1045 << FixItHint::CreateReplacement(BeginLoc, "static_cast");
1046}
1047
1048static bool argTypeIsABIEquivalent(QualType SrcType, QualType DestType,
1049 ASTContext &Context) {
1050 if (SrcType->isPointerType() && DestType->isPointerType())
1051 return true;
1052
1053 // Allow integral type mismatch if their size are equal.
1054 if (SrcType->isIntegralType(Context) && DestType->isIntegralType(Context))
1055 if (Context.getTypeInfoInChars(SrcType).Width ==
1056 Context.getTypeInfoInChars(DestType).Width)
1057 return true;
1058
1059 return Context.hasSameUnqualifiedType(SrcType, DestType);
1060}
1061
1062static bool checkCastFunctionType(Sema &Self, const ExprResult &SrcExpr,
1063 QualType DestType) {
1064 if (Self.Diags.isIgnored(diag::warn_cast_function_type,
1065 SrcExpr.get()->getExprLoc()))
1066 return true;
1067
1068 QualType SrcType = SrcExpr.get()->getType();
1069 const FunctionType *SrcFTy = nullptr;
1070 const FunctionType *DstFTy = nullptr;
1071 if (((SrcType->isBlockPointerType() || SrcType->isFunctionPointerType()) &&
1072 DestType->isFunctionPointerType()) ||
1073 (SrcType->isMemberFunctionPointerType() &&
1074 DestType->isMemberFunctionPointerType())) {
1075 SrcFTy = SrcType->getPointeeType()->castAs<FunctionType>();
1076 DstFTy = DestType->getPointeeType()->castAs<FunctionType>();
1077 } else if (SrcType->isFunctionType() && DestType->isFunctionReferenceType()) {
1078 SrcFTy = SrcType->castAs<FunctionType>();
1079 DstFTy = DestType.getNonReferenceType()->castAs<FunctionType>();
1080 } else {
1081 return true;
1082 }
1083 assert(SrcFTy && DstFTy)((void)0);
1084
1085 auto IsVoidVoid = [](const FunctionType *T) {
1086 if (!T->getReturnType()->isVoidType())
1087 return false;
1088 if (const auto *PT = T->getAs<FunctionProtoType>())
1089 return !PT->isVariadic() && PT->getNumParams() == 0;
1090 return false;
1091 };
1092
1093 // Skip if either function type is void(*)(void)
1094 if (IsVoidVoid(SrcFTy) || IsVoidVoid(DstFTy))
1095 return true;
1096
1097 // Check return type.
1098 if (!argTypeIsABIEquivalent(SrcFTy->getReturnType(), DstFTy->getReturnType(),
1099 Self.Context))
1100 return false;
1101
1102 // Check if either has unspecified number of parameters
1103 if (SrcFTy->isFunctionNoProtoType() || DstFTy->isFunctionNoProtoType())
1104 return true;
1105
1106 // Check parameter types.
1107
1108 const auto *SrcFPTy = cast<FunctionProtoType>(SrcFTy);
1109 const auto *DstFPTy = cast<FunctionProtoType>(DstFTy);
1110
1111 // In a cast involving function types with a variable argument list only the
1112 // types of initial arguments that are provided are considered.
1113 unsigned NumParams = SrcFPTy->getNumParams();
1114 unsigned DstNumParams = DstFPTy->getNumParams();
1115 if (NumParams > DstNumParams) {
1116 if (!DstFPTy->isVariadic())
1117 return false;
1118 NumParams = DstNumParams;
1119 } else if (NumParams < DstNumParams) {
1120 if (!SrcFPTy->isVariadic())
1121 return false;
1122 }
1123
1124 for (unsigned i = 0; i < NumParams; ++i)
1125 if (!argTypeIsABIEquivalent(SrcFPTy->getParamType(i),
1126 DstFPTy->getParamType(i), Self.Context))
1127 return false;
1128
1129 return true;
1130}
1131
1132/// CheckReinterpretCast - Check that a reinterpret_cast\<DestType\>(SrcExpr) is
1133/// valid.
1134/// Refer to C++ 5.2.10 for details. reinterpret_cast is typically used in code
1135/// like this:
1136/// char *bytes = reinterpret_cast\<char*\>(int_ptr);
1137void CastOperation::CheckReinterpretCast() {
1138 if (ValueKind == VK_PRValue && !isPlaceholder(BuiltinType::Overload))
1139 SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
1140 else
1141 checkNonOverloadPlaceholders();
1142 if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
1143 return;
1144
1145 unsigned msg = diag::err_bad_cxx_cast_generic;
1146 TryCastResult tcr =
1147 TryReinterpretCast(Self, SrcExpr, DestType,
1148 /*CStyle*/false, OpRange, msg, Kind);
1149 if (tcr != TC_Success && msg != 0) {
1150 if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
1151 return;
1152 if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1153 //FIXME: &f<int>; is overloaded and resolvable
1154 Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_overload)
1155 << OverloadExpr::find(SrcExpr.get()).Expression->getName()
1156 << DestType << OpRange;
1157 Self.NoteAllOverloadCandidates(SrcExpr.get());
1158
1159 } else {
1160 diagnoseBadCast(Self, msg, CT_Reinterpret, OpRange, SrcExpr.get(),
1161 DestType, /*listInitialization=*/false);
1162 }
1163 }
1164
1165 if (isValidCast(tcr)) {
1166 if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
1167 checkObjCConversion(Sema::CCK_OtherCast);
1168 DiagnoseReinterpretUpDownCast(Self, SrcExpr.get(), DestType, OpRange);
1169
1170 if (!checkCastFunctionType(Self, SrcExpr, DestType))
1171 Self.Diag(OpRange.getBegin(), diag::warn_cast_function_type)
1172 << SrcExpr.get()->getType() << DestType << OpRange;
1173 } else {
1174 SrcExpr = ExprError();
1175 }
1176}
1177
1178
1179/// CheckStaticCast - Check that a static_cast\<DestType\>(SrcExpr) is valid.
1180/// Refer to C++ 5.2.9 for details. Static casts are mostly used for making
1181/// implicit conversions explicit and getting rid of data loss warnings.
1182void CastOperation::CheckStaticCast() {
1183 CheckNoDerefRAII NoderefCheck(*this);
1184
1185 if (isPlaceholder()) {
10
Taking false branch
1186 checkNonOverloadPlaceholders();
1187 if (SrcExpr.isInvalid())
1188 return;
1189 }
1190
1191 // This test is outside everything else because it's the only case where
1192 // a non-lvalue-reference target type does not lead to decay.
1193 // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
1194 if (DestType->isVoidType()) {
11
Taking false branch
1195 Kind = CK_ToVoid;
1196
1197 if (claimPlaceholder(BuiltinType::Overload)) {
1198 Self.ResolveAndFixSingleFunctionTemplateSpecialization(SrcExpr,
1199 false, // Decay Function to ptr
1200 true, // Complain
1201 OpRange, DestType, diag::err_bad_static_cast_overload);
1202 if (SrcExpr.isInvalid())
1203 return;
1204 }
1205
1206 SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
1207 return;
1208 }
1209
1210 if (ValueKind == VK_PRValue && !DestType->isRecordType() &&
12
Assuming field 'ValueKind' is not equal to VK_PRValue
1211 !isPlaceholder(BuiltinType::Overload)) {
1212 SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
1213 if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
1214 return;
1215 }
1216
1217 unsigned msg = diag::err_bad_cxx_cast_generic;
1218 TryCastResult tcr
1219 = TryStaticCast(Self, SrcExpr, DestType, Sema::CCK_OtherCast, OpRange, msg,
13
Calling 'TryStaticCast'
1220 Kind, BasePath, /*ListInitialization=*/false);
1221 if (tcr != TC_Success && msg != 0) {
1222 if (SrcExpr.isInvalid())
1223 return;
1224 if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1225 OverloadExpr* oe = OverloadExpr::find(SrcExpr.get()).Expression;
1226 Self.Diag(OpRange.getBegin(), diag::err_bad_static_cast_overload)
1227 << oe->getName() << DestType << OpRange
1228 << oe->getQualifierLoc().getSourceRange();
1229 Self.NoteAllOverloadCandidates(SrcExpr.get());
1230 } else {
1231 diagnoseBadCast(Self, msg, CT_Static, OpRange, SrcExpr.get(), DestType,
1232 /*listInitialization=*/false);
1233 }
1234 }
1235
1236 if (isValidCast(tcr)) {
1237 if (Kind == CK_BitCast)
1238 checkCastAlign();
1239 if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
1240 checkObjCConversion(Sema::CCK_OtherCast);
1241 } else {
1242 SrcExpr = ExprError();
1243 }
1244}
1245
1246static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType) {
1247 auto *SrcPtrType = SrcType->getAs<PointerType>();
1248 if (!SrcPtrType)
1249 return false;
1250 auto *DestPtrType = DestType->getAs<PointerType>();
1251 if (!DestPtrType)
1252 return false;
1253 return SrcPtrType->getPointeeType().getAddressSpace() !=
1254 DestPtrType->getPointeeType().getAddressSpace();
1255}
1256
1257/// TryStaticCast - Check if a static cast can be performed, and do so if
1258/// possible. If @p CStyle, ignore access restrictions on hierarchy casting
1259/// and casting away constness.
1260static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
1261 QualType DestType,
1262 Sema::CheckedConversionKind CCK,
1263 SourceRange OpRange, unsigned &msg,
1264 CastKind &Kind, CXXCastPath &BasePath,
1265 bool ListInitialization) {
1266 // Determine whether we have the semantics of a C-style cast.
1267 bool CStyle
1268 = (CCK
13.1
'CCK' is not equal to CCK_CStyleCast
13.1
'CCK' is not equal to CCK_CStyleCast
== Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1269
1270 // The order the tests is not entirely arbitrary. There is one conversion
1271 // that can be handled in two different ways. Given:
1272 // struct A {};
1273 // struct B : public A {
1274 // B(); B(const A&);
1275 // };
1276 // const A &a = B();
1277 // the cast static_cast<const B&>(a) could be seen as either a static
1278 // reference downcast, or an explicit invocation of the user-defined
1279 // conversion using B's conversion constructor.
1280 // DR 427 specifies that the downcast is to be applied here.
1281
1282 // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
1283 // Done outside this function.
1284
1285 TryCastResult tcr;
1286
1287 // C++ 5.2.9p5, reference downcast.
1288 // See the function for details.
1289 // DR 427 specifies that this is to be applied before paragraph 2.
1290 tcr = TryStaticReferenceDowncast(Self, SrcExpr.get(), DestType, CStyle,
1291 OpRange, msg, Kind, BasePath);
1292 if (tcr
13.2
'tcr' is equal to TC_NotApplicable
13.2
'tcr' is equal to TC_NotApplicable
!= TC_NotApplicable)
14
Taking false branch
1293 return tcr;
1294
1295 // C++11 [expr.static.cast]p3:
1296 // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to cv2
1297 // T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1298 tcr = TryLValueToRValueCast(Self, SrcExpr.get(), DestType, CStyle, Kind,
1299 BasePath, msg);
1300 if (tcr
14.1
'tcr' is equal to TC_NotApplicable
14.1
'tcr' is equal to TC_NotApplicable
!= TC_NotApplicable)
15
Taking false branch
1301 return tcr;
1302
1303 // C++ 5.2.9p2: An expression e can be explicitly converted to a type T
1304 // [...] if the declaration "T t(e);" is well-formed, [...].
1305 tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg,
1306 Kind, ListInitialization);
1307 if (SrcExpr.isInvalid())
16
Assuming the condition is false
17
Taking false branch
1308 return TC_Failed;
1309 if (tcr
17.1
'tcr' is equal to TC_NotApplicable
17.1
'tcr' is equal to TC_NotApplicable
!= TC_NotApplicable)
18
Taking false branch
1310 return tcr;
1311
1312 // C++ 5.2.9p6: May apply the reverse of any standard conversion, except
1313 // lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
1314 // conversions, subject to further restrictions.
1315 // Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
1316 // of qualification conversions impossible.
1317 // In the CStyle case, the earlier attempt to const_cast should have taken
1318 // care of reverse qualification conversions.
1319
1320 QualType SrcType = Self.Context.getCanonicalType(SrcExpr.get()->getType());
1321
1322 // C++0x 5.2.9p9: A value of a scoped enumeration type can be explicitly
1323 // converted to an integral type. [...] A value of a scoped enumeration type
1324 // can also be explicitly converted to a floating-point type [...].
1325 if (const EnumType *Enum
19.1
'Enum' is null
19.1
'Enum' is null
= SrcType->getAs<EnumType>()) {
19
Assuming the object is not a 'EnumType'
20
Taking false branch
1326 if (Enum->getDecl()->isScoped()) {
1327 if (DestType->isBooleanType()) {
1328 Kind = CK_IntegralToBoolean;
1329 return TC_Success;
1330 } else if (DestType->isIntegralType(Self.Context)) {
1331 Kind = CK_IntegralCast;
1332 return TC_Success;
1333 } else if (DestType->isRealFloatingType()) {
1334 Kind = CK_IntegralToFloating;
1335 return TC_Success;
1336 }
1337 }
1338 }
1339
1340 // Reverse integral promotion/conversion. All such conversions are themselves
1341 // again integral promotions or conversions and are thus already handled by
1342 // p2 (TryDirectInitialization above).
1343 // (Note: any data loss warnings should be suppressed.)
1344 // The exception is the reverse of enum->integer, i.e. integer->enum (and
1345 // enum->enum). See also C++ 5.2.9p7.
1346 // The same goes for reverse floating point promotion/conversion and
1347 // floating-integral conversions. Again, only floating->enum is relevant.
1348 if (DestType->isEnumeralType()) {
21
Calling 'Type::isEnumeralType'
24
Returning from 'Type::isEnumeralType'
25
Taking true branch
1349 if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
26
Assuming the condition is false
27
Taking false branch
1350 diag::err_bad_cast_incomplete)) {
1351 SrcExpr = ExprError();
1352 return TC_Failed;
1353 }
1354 if (SrcType->isIntegralOrEnumerationType()) {
28
Calling 'Type::isIntegralOrEnumerationType'
38
Returning from 'Type::isIntegralOrEnumerationType'
39
Taking true branch
1355 // [expr.static.cast]p10 If the enumeration type has a fixed underlying
1356 // type, the value is first converted to that type by integral conversion
1357 const EnumType *Enum = DestType->getAs<EnumType>();
40
Assuming the object is not a 'EnumType'
41
'Enum' initialized to a null pointer value
1358 Kind = Enum->getDecl()->isFixed() &&
42
Called C++ object pointer is null
1359 Enum->getDecl()->getIntegerType()->isBooleanType()
1360 ? CK_IntegralToBoolean
1361 : CK_IntegralCast;
1362 return TC_Success;
1363 } else if (SrcType->isRealFloatingType()) {
1364 Kind = CK_FloatingToIntegral;
1365 return TC_Success;
1366 }
1367 }
1368
1369 // Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
1370 // C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
1371 tcr = TryStaticPointerDowncast(Self, SrcType, DestType, CStyle, OpRange, msg,
1372 Kind, BasePath);
1373 if (tcr != TC_NotApplicable)
1374 return tcr;
1375
1376 // Reverse member pointer conversion. C++ 4.11 specifies member pointer
1377 // conversion. C++ 5.2.9p9 has additional information.
1378 // DR54's access restrictions apply here also.
1379 tcr = TryStaticMemberPointerUpcast(Self, SrcExpr, SrcType, DestType, CStyle,
1380 OpRange, msg, Kind, BasePath);
1381 if (tcr != TC_NotApplicable)
1382 return tcr;
1383
1384 // Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
1385 // void*. C++ 5.2.9p10 specifies additional restrictions, which really is
1386 // just the usual constness stuff.
1387 if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
1388 QualType SrcPointee = SrcPointer->getPointeeType();
1389 if (SrcPointee->isVoidType()) {
1390 if (const PointerType *DestPointer = DestType->getAs<PointerType>()) {
1391 QualType DestPointee = DestPointer->getPointeeType();
1392 if (DestPointee->isIncompleteOrObjectType()) {
1393 // This is definitely the intended conversion, but it might fail due
1394 // to a qualifier violation. Note that we permit Objective-C lifetime
1395 // and GC qualifier mismatches here.
1396 if (!CStyle) {
1397 Qualifiers DestPointeeQuals = DestPointee.getQualifiers();
1398 Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers();
1399 DestPointeeQuals.removeObjCGCAttr();
1400 DestPointeeQuals.removeObjCLifetime();
1401 SrcPointeeQuals.removeObjCGCAttr();
1402 SrcPointeeQuals.removeObjCLifetime();
1403 if (DestPointeeQuals != SrcPointeeQuals &&
1404 !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) {
1405 msg = diag::err_bad_cxx_cast_qualifiers_away;
1406 return TC_Failed;
1407 }
1408 }
1409 Kind = IsAddressSpaceConversion(SrcType, DestType)
1410 ? CK_AddressSpaceConversion
1411 : CK_BitCast;
1412 return TC_Success;
1413 }
1414
1415 // Microsoft permits static_cast from 'pointer-to-void' to
1416 // 'pointer-to-function'.
1417 if (!CStyle && Self.getLangOpts().MSVCCompat &&
1418 DestPointee->isFunctionType()) {
1419 Self.Diag(OpRange.getBegin(), diag::ext_ms_cast_fn_obj) << OpRange;
1420 Kind = CK_BitCast;
1421 return TC_Success;
1422 }
1423 }
1424 else if (DestType->isObjCObjectPointerType()) {
1425 // allow both c-style cast and static_cast of objective-c pointers as
1426 // they are pervasive.
1427 Kind = CK_CPointerToObjCPointerCast;
1428 return TC_Success;
1429 }
1430 else if (CStyle && DestType->isBlockPointerType()) {
1431 // allow c-style cast of void * to block pointers.
1432 Kind = CK_AnyPointerToBlockPointerCast;
1433 return TC_Success;
1434 }
1435 }
1436 }
1437 // Allow arbitrary objective-c pointer conversion with static casts.
1438 if (SrcType->isObjCObjectPointerType() &&
1439 DestType->isObjCObjectPointerType()) {
1440 Kind = CK_BitCast;
1441 return TC_Success;
1442 }
1443 // Allow ns-pointer to cf-pointer conversion in either direction
1444 // with static casts.
1445 if (!CStyle &&
1446 Self.CheckTollFreeBridgeStaticCast(DestType, SrcExpr.get(), Kind))
1447 return TC_Success;
1448
1449 // See if it looks like the user is trying to convert between
1450 // related record types, and select a better diagnostic if so.
1451 if (auto SrcPointer = SrcType->getAs<PointerType>())
1452 if (auto DestPointer = DestType->getAs<PointerType>())
1453 if (SrcPointer->getPointeeType()->getAs<RecordType>() &&
1454 DestPointer->getPointeeType()->getAs<RecordType>())
1455 msg = diag::err_bad_cxx_cast_unrelated_class;
1456
1457 if (SrcType->isMatrixType() && DestType->isMatrixType()) {
1458 if (Self.CheckMatrixCast(OpRange, DestType, SrcType, Kind)) {
1459 SrcExpr = ExprError();
1460 return TC_Failed;
1461 }
1462 return TC_Success;
1463 }
1464
1465 // We tried everything. Everything! Nothing works! :-(
1466 return TC_NotApplicable;
1467}
1468
1469/// Tests whether a conversion according to N2844 is valid.
1470TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
1471 QualType DestType, bool CStyle,
1472 CastKind &Kind, CXXCastPath &BasePath,
1473 unsigned &msg) {
1474 // C++11 [expr.static.cast]p3:
1475 // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
1476 // cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1477 const RValueReferenceType *R = DestType->getAs<RValueReferenceType>();
1478 if (!R)
1479 return TC_NotApplicable;
1480
1481 if (!SrcExpr->isGLValue())
1482 return TC_NotApplicable;
1483
1484 // Because we try the reference downcast before this function, from now on
1485 // this is the only cast possibility, so we issue an error if we fail now.
1486 // FIXME: Should allow casting away constness if CStyle.
1487 QualType FromType = SrcExpr->getType();
1488 QualType ToType = R->getPointeeType();
1489 if (CStyle) {
1490 FromType = FromType.getUnqualifiedType();
1491 ToType = ToType.getUnqualifiedType();
1492 }
1493
1494 Sema::ReferenceConversions RefConv;
1495 Sema::ReferenceCompareResult RefResult = Self.CompareReferenceRelationship(
1496 SrcExpr->getBeginLoc(), ToType, FromType, &RefConv);
1497 if (RefResult != Sema::Ref_Compatible) {
1498 if (CStyle || RefResult == Sema::Ref_Incompatible)
1499 return TC_NotApplicable;
1500 // Diagnose types which are reference-related but not compatible here since
1501 // we can provide better diagnostics. In these cases forwarding to
1502 // [expr.static.cast]p4 should never result in a well-formed cast.
1503 msg = SrcExpr->isLValue() ? diag::err_bad_lvalue_to_rvalue_cast
1504 : diag::err_bad_rvalue_to_rvalue_cast;
1505 return TC_Failed;
1506 }
1507
1508 if (RefConv & Sema::ReferenceConversions::DerivedToBase) {
1509 Kind = CK_DerivedToBase;
1510 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1511 /*DetectVirtual=*/true);
1512 if (!Self.IsDerivedFrom(SrcExpr->getBeginLoc(), SrcExpr->getType(),
1513 R->getPointeeType(), Paths))
1514 return TC_NotApplicable;
1515
1516 Self.BuildBasePathArray(Paths, BasePath);
1517 } else
1518 Kind = CK_NoOp;
1519
1520 return TC_Success;
1521}
1522
1523/// Tests whether a conversion according to C++ 5.2.9p5 is valid.
1524TryCastResult
1525TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType,
1526 bool CStyle, SourceRange OpRange,
1527 unsigned &msg, CastKind &Kind,
1528 CXXCastPath &BasePath) {
1529 // C++ 5.2.9p5: An lvalue of type "cv1 B", where B is a class type, can be
1530 // cast to type "reference to cv2 D", where D is a class derived from B,
1531 // if a valid standard conversion from "pointer to D" to "pointer to B"
1532 // exists, cv2 >= cv1, and B is not a virtual base class of D.
1533 // In addition, DR54 clarifies that the base must be accessible in the
1534 // current context. Although the wording of DR54 only applies to the pointer
1535 // variant of this rule, the intent is clearly for it to apply to the this
1536 // conversion as well.
1537
1538 const ReferenceType *DestReference = DestType->getAs<ReferenceType>();
1539 if (!DestReference) {
1540 return TC_NotApplicable;
1541 }
1542 bool RValueRef = DestReference->isRValueReferenceType();
1543 if (!RValueRef && !SrcExpr->isLValue()) {
1544 // We know the left side is an lvalue reference, so we can suggest a reason.
1545 msg = diag::err_bad_cxx_cast_rvalue;
1546 return TC_NotApplicable;
1547 }
1548
1549 QualType DestPointee = DestReference->getPointeeType();
1550
1551 // FIXME: If the source is a prvalue, we should issue a warning (because the
1552 // cast always has undefined behavior), and for AST consistency, we should
1553 // materialize a temporary.
1554 return TryStaticDowncast(Self,
1555 Self.Context.getCanonicalType(SrcExpr->getType()),
1556 Self.Context.getCanonicalType(DestPointee), CStyle,
1557 OpRange, SrcExpr->getType(), DestType, msg, Kind,
1558 BasePath);
1559}
1560
1561/// Tests whether a conversion according to C++ 5.2.9p8 is valid.
1562TryCastResult
1563TryStaticPointerDowncast(Sema &Self, QualType SrcType, QualType DestType,
1564 bool CStyle, SourceRange OpRange,
1565 unsigned &msg, CastKind &Kind,
1566 CXXCastPath &BasePath) {
1567 // C++ 5.2.9p8: An rvalue of type "pointer to cv1 B", where B is a class
1568 // type, can be converted to an rvalue of type "pointer to cv2 D", where D
1569 // is a class derived from B, if a valid standard conversion from "pointer
1570 // to D" to "pointer to B" exists, cv2 >= cv1, and B is not a virtual base
1571 // class of D.
1572 // In addition, DR54 clarifies that the base must be accessible in the
1573 // current context.
1574
1575 const PointerType *DestPointer = DestType->getAs<PointerType>();
1576 if (!DestPointer) {
1577 return TC_NotApplicable;
1578 }
1579
1580 const PointerType *SrcPointer = SrcType->getAs<PointerType>();
1581 if (!SrcPointer) {
1582 msg = diag::err_bad_static_cast_pointer_nonpointer;
1583 return TC_NotApplicable;
1584 }
1585
1586 return TryStaticDowncast(Self,
1587 Self.Context.getCanonicalType(SrcPointer->getPointeeType()),
1588 Self.Context.getCanonicalType(DestPointer->getPointeeType()),
1589 CStyle, OpRange, SrcType, DestType, msg, Kind,
1590 BasePath);
1591}
1592
1593/// TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and
1594/// TryStaticPointerDowncast. Tests whether a static downcast from SrcType to
1595/// DestType is possible and allowed.
1596TryCastResult
1597TryStaticDowncast(Sema &Self, CanQualType SrcType, CanQualType DestType,
1598 bool CStyle, SourceRange OpRange, QualType OrigSrcType,
1599 QualType OrigDestType, unsigned &msg,
1600 CastKind &Kind, CXXCastPath &BasePath) {
1601 // We can only work with complete types. But don't complain if it doesn't work
1602 if (!Self.isCompleteType(OpRange.getBegin(), SrcType) ||
1603 !Self.isCompleteType(OpRange.getBegin(), DestType))
1604 return TC_NotApplicable;
1605
1606 // Downcast can only happen in class hierarchies, so we need classes.
1607 if (!DestType->getAs<RecordType>() || !SrcType->getAs<RecordType>()) {
1608 return TC_NotApplicable;
1609 }
1610
1611 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1612 /*DetectVirtual=*/true);
1613 if (!Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths)) {
1614 return TC_NotApplicable;
1615 }
1616
1617 // Target type does derive from source type. Now we're serious. If an error
1618 // appears now, it's not ignored.
1619 // This may not be entirely in line with the standard. Take for example:
1620 // struct A {};
1621 // struct B : virtual A {
1622 // B(A&);
1623 // };
1624 //
1625 // void f()
1626 // {
1627 // (void)static_cast<const B&>(*((A*)0));
1628 // }
1629 // As far as the standard is concerned, p5 does not apply (A is virtual), so
1630 // p2 should be used instead - "const B& t(*((A*)0));" is perfectly valid.
1631 // However, both GCC and Comeau reject this example, and accepting it would
1632 // mean more complex code if we're to preserve the nice error message.
1633 // FIXME: Being 100% compliant here would be nice to have.
1634
1635 // Must preserve cv, as always, unless we're in C-style mode.
1636 if (!CStyle && !DestType.isAtLeastAsQualifiedAs(SrcType)) {
1637 msg = diag::err_bad_cxx_cast_qualifiers_away;
1638 return TC_Failed;
1639 }
1640
1641 if (Paths.isAmbiguous(SrcType.getUnqualifiedType())) {
1642 // This code is analoguous to that in CheckDerivedToBaseConversion, except
1643 // that it builds the paths in reverse order.
1644 // To sum up: record all paths to the base and build a nice string from
1645 // them. Use it to spice up the error message.
1646 if (!Paths.isRecordingPaths()) {
1647 Paths.clear();
1648 Paths.setRecordingPaths(true);
1649 Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths);
1650 }
1651 std::string PathDisplayStr;
1652 std::set<unsigned> DisplayedPaths;
1653 for (clang::CXXBasePath &Path : Paths) {
1654 if (DisplayedPaths.insert(Path.back().SubobjectNumber).second) {
1655 // We haven't displayed a path to this particular base
1656 // class subobject yet.
1657 PathDisplayStr += "\n ";
1658 for (CXXBasePathElement &PE : llvm::reverse(Path))
1659 PathDisplayStr += PE.Base->getType().getAsString() + " -> ";
1660 PathDisplayStr += QualType(DestType).getAsString();
1661 }
1662 }
1663
1664 Self.Diag(OpRange.getBegin(), diag::err_ambiguous_base_to_derived_cast)
1665 << QualType(SrcType).getUnqualifiedType()
1666 << QualType(DestType).getUnqualifiedType()
1667 << PathDisplayStr << OpRange;
1668 msg = 0;
1669 return TC_Failed;
1670 }
1671
1672 if (Paths.getDetectedVirtual() != nullptr) {
1673 QualType VirtualBase(Paths.getDetectedVirtual(), 0);
1674 Self.Diag(OpRange.getBegin(), diag::err_static_downcast_via_virtual)
1675 << OrigSrcType << OrigDestType << VirtualBase << OpRange;
1676 msg = 0;
1677 return TC_Failed;
1678 }
1679
1680 if (!CStyle) {
1681 switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1682 SrcType, DestType,
1683 Paths.front(),
1684 diag::err_downcast_from_inaccessible_base)) {
1685 case Sema::AR_accessible:
1686 case Sema::AR_delayed: // be optimistic
1687 case Sema::AR_dependent: // be optimistic
1688 break;
1689
1690 case Sema::AR_inaccessible:
1691 msg = 0;
1692 return TC_Failed;
1693 }
1694 }
1695
1696 Self.BuildBasePathArray(Paths, BasePath);
1697 Kind = CK_BaseToDerived;
1698 return TC_Success;
1699}
1700
1701/// TryStaticMemberPointerUpcast - Tests whether a conversion according to
1702/// C++ 5.2.9p9 is valid:
1703///
1704/// An rvalue of type "pointer to member of D of type cv1 T" can be
1705/// converted to an rvalue of type "pointer to member of B of type cv2 T",
1706/// where B is a base class of D [...].
1707///
1708TryCastResult
1709TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr, QualType SrcType,
1710 QualType DestType, bool CStyle,
1711 SourceRange OpRange,
1712 unsigned &msg, CastKind &Kind,
1713 CXXCastPath &BasePath) {
1714 const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>();
1715 if (!DestMemPtr)
1716 return TC_NotApplicable;
1717
1718 bool WasOverloadedFunction = false;
1719 DeclAccessPair FoundOverload;
1720 if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1721 if (FunctionDecl *Fn
1722 = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(), DestType, false,
1723 FoundOverload)) {
1724 CXXMethodDecl *M = cast<CXXMethodDecl>(Fn);
1725 SrcType = Self.Context.getMemberPointerType(Fn->getType(),
1726 Self.Context.getTypeDeclType(M->getParent()).getTypePtr());
1727 WasOverloadedFunction = true;
1728 }
1729 }
1730
1731 const MemberPointerType *SrcMemPtr = SrcType->getAs<MemberPointerType>();
1732 if (!SrcMemPtr) {
1733 msg = diag::err_bad_static_cast_member_pointer_nonmp;
1734 return TC_NotApplicable;
1735 }
1736
1737 // Lock down the inheritance model right now in MS ABI, whether or not the
1738 // pointee types are the same.
1739 if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1740 (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
1741 (void)Self.isCompleteType(OpRange.getBegin(), DestType);
1742 }
1743
1744 // T == T, modulo cv
1745 if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
1746 DestMemPtr->getPointeeType()))
1747 return TC_NotApplicable;
1748
1749 // B base of D
1750 QualType SrcClass(SrcMemPtr->getClass(), 0);
1751 QualType DestClass(DestMemPtr->getClass(), 0);
1752 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1753 /*DetectVirtual=*/true);
1754 if (!Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths))
1755 return TC_NotApplicable;
1756
1757 // B is a base of D. But is it an allowed base? If not, it's a hard error.
1758 if (Paths.isAmbiguous(Self.Context.getCanonicalType(DestClass))) {
1759 Paths.clear();
1760 Paths.setRecordingPaths(true);
1761 bool StillOkay =
1762 Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths);
1763 assert(StillOkay)((void)0);
1764 (void)StillOkay;
1765 std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
1766 Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
1767 << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
1768 msg = 0;
1769 return TC_Failed;
1770 }
1771
1772 if (const RecordType *VBase = Paths.getDetectedVirtual()) {
1773 Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
1774 << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
1775 msg = 0;
1776 return TC_Failed;
1777 }
1778
1779 if (!CStyle) {
1780 switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1781 DestClass, SrcClass,
1782 Paths.front(),
1783 diag::err_upcast_to_inaccessible_base)) {
1784 case Sema::AR_accessible:
1785 case Sema::AR_delayed:
1786 case Sema::AR_dependent:
1787 // Optimistically assume that the delayed and dependent cases
1788 // will work out.
1789 break;
1790
1791 case Sema::AR_inaccessible:
1792 msg = 0;
1793 return TC_Failed;
1794 }
1795 }
1796
1797 if (WasOverloadedFunction) {
1798 // Resolve the address of the overloaded function again, this time
1799 // allowing complaints if something goes wrong.
1800 FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
1801 DestType,
1802 true,
1803 FoundOverload);
1804 if (!Fn) {
1805 msg = 0;
1806 return TC_Failed;
1807 }
1808
1809 SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr, FoundOverload, Fn);
1810 if (!SrcExpr.isUsable()) {
1811 msg = 0;
1812 return TC_Failed;
1813 }
1814 }
1815
1816 Self.BuildBasePathArray(Paths, BasePath);
1817 Kind = CK_DerivedToBaseMemberPointer;
1818 return TC_Success;
1819}
1820
1821/// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
1822/// is valid:
1823///
1824/// An expression e can be explicitly converted to a type T using a
1825/// @c static_cast if the declaration "T t(e);" is well-formed [...].
1826TryCastResult
1827TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType,
1828 Sema::CheckedConversionKind CCK,
1829 SourceRange OpRange, unsigned &msg,
1830 CastKind &Kind, bool ListInitialization) {
1831 if (DestType->isRecordType()) {
1832 if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
1833 diag::err_bad_cast_incomplete) ||
1834 Self.RequireNonAbstractType(OpRange.getBegin(), DestType,
1835 diag::err_allocation_of_abstract_type)) {
1836 msg = 0;
1837 return TC_Failed;
1838 }
1839 }
1840
1841 InitializedEntity Entity = InitializedEntity::InitializeTemporary(DestType);
1842 InitializationKind InitKind
1843 = (CCK == Sema::CCK_CStyleCast)
1844 ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange,
1845 ListInitialization)
1846 : (CCK == Sema::CCK_FunctionalCast)
1847 ? InitializationKind::CreateFunctionalCast(OpRange, ListInitialization)
1848 : InitializationKind::CreateCast(OpRange);
1849 Expr *SrcExprRaw = SrcExpr.get();
1850 // FIXME: Per DR242, we should check for an implicit conversion sequence
1851 // or for a constructor that could be invoked by direct-initialization
1852 // here, not for an initialization sequence.
1853 InitializationSequence InitSeq(Self, Entity, InitKind, SrcExprRaw);
1854
1855 // At this point of CheckStaticCast, if the destination is a reference,
1856 // or the expression is an overload expression this has to work.
1857 // There is no other way that works.
1858 // On the other hand, if we're checking a C-style cast, we've still got
1859 // the reinterpret_cast way.
1860 bool CStyle
1861 = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1862 if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType()))
1863 return TC_NotApplicable;
1864
1865 ExprResult Result = InitSeq.Perform(Self, Entity, InitKind, SrcExprRaw);
1866 if (Result.isInvalid()) {
1867 msg = 0;
1868 return TC_Failed;
1869 }
1870
1871 if (InitSeq.isConstructorInitialization())
1872 Kind = CK_ConstructorConversion;
1873 else
1874 Kind = CK_NoOp;
1875
1876 SrcExpr = Result;
1877 return TC_Success;
1878}
1879
1880/// TryConstCast - See if a const_cast from source to destination is allowed,
1881/// and perform it if it is.
1882static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
1883 QualType DestType, bool CStyle,
1884 unsigned &msg) {
1885 DestType = Self.Context.getCanonicalType(DestType);
1886 QualType SrcType = SrcExpr.get()->getType();
1887 bool NeedToMaterializeTemporary = false;
1888
1889 if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
1890 // C++11 5.2.11p4:
1891 // if a pointer to T1 can be explicitly converted to the type "pointer to
1892 // T2" using a const_cast, then the following conversions can also be
1893 // made:
1894 // -- an lvalue of type T1 can be explicitly converted to an lvalue of
1895 // type T2 using the cast const_cast<T2&>;
1896 // -- a glvalue of type T1 can be explicitly converted to an xvalue of
1897 // type T2 using the cast const_cast<T2&&>; and
1898 // -- if T1 is a class type, a prvalue of type T1 can be explicitly
1899 // converted to an xvalue of type T2 using the cast const_cast<T2&&>.
1900
1901 if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr.get()->isLValue()) {
1902 // Cannot const_cast non-lvalue to lvalue reference type. But if this
1903 // is C-style, static_cast might find a way, so we simply suggest a
1904 // message and tell the parent to keep searching.
1905 msg = diag::err_bad_cxx_cast_rvalue;
1906 return TC_NotApplicable;
1907 }
1908
1909 if (isa<RValueReferenceType>(DestTypeTmp) && SrcExpr.get()->isPRValue()) {
1910 if (!SrcType->isRecordType()) {
1911 // Cannot const_cast non-class prvalue to rvalue reference type. But if
1912 // this is C-style, static_cast can do this.
1913 msg = diag::err_bad_cxx_cast_rvalue;
1914 return TC_NotApplicable;
1915 }
1916
1917 // Materialize the class prvalue so that the const_cast can bind a
1918 // reference to it.
1919 NeedToMaterializeTemporary = true;
1920 }
1921
1922 // It's not completely clear under the standard whether we can
1923 // const_cast bit-field gl-values. Doing so would not be
1924 // intrinsically complicated, but for now, we say no for
1925 // consistency with other compilers and await the word of the
1926 // committee.
1927 if (SrcExpr.get()->refersToBitField()) {
1928 msg = diag::err_bad_cxx_cast_bitfield;
1929 return TC_NotApplicable;
1930 }
1931
1932 DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
1933 SrcType = Self.Context.getPointerType(SrcType);
1934 }
1935
1936 // C++ 5.2.11p5: For a const_cast involving pointers to data members [...]
1937 // the rules for const_cast are the same as those used for pointers.
1938
1939 if (!DestType->isPointerType() &&
1940 !DestType->isMemberPointerType() &&
1941 !DestType->isObjCObjectPointerType()) {
1942 // Cannot cast to non-pointer, non-reference type. Note that, if DestType
1943 // was a reference type, we converted it to a pointer above.
1944 // The status of rvalue references isn't entirely clear, but it looks like
1945 // conversion to them is simply invalid.
1946 // C++ 5.2.11p3: For two pointer types [...]
1947 if (!CStyle)
1948 msg = diag::err_bad_const_cast_dest;
1949 return TC_NotApplicable;
1950 }
1951 if (DestType->isFunctionPointerType() ||
1952 DestType->isMemberFunctionPointerType()) {
1953 // Cannot cast direct function pointers.
1954 // C++ 5.2.11p2: [...] where T is any object type or the void type [...]
1955 // T is the ultimate pointee of source and target type.
1956 if (!CStyle)
1957 msg = diag::err_bad_const_cast_dest;
1958 return TC_NotApplicable;
1959 }
1960
1961 // C++ [expr.const.cast]p3:
1962 // "For two similar types T1 and T2, [...]"
1963 //
1964 // We only allow a const_cast to change cvr-qualifiers, not other kinds of
1965 // type qualifiers. (Likewise, we ignore other changes when determining
1966 // whether a cast casts away constness.)
1967 if (!Self.Context.hasCvrSimilarType(SrcType, DestType))
1968 return TC_NotApplicable;
1969
1970 if (NeedToMaterializeTemporary)
1971 // This is a const_cast from a class prvalue to an rvalue reference type.
1972 // Materialize a temporary to store the result of the conversion.
1973 SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcExpr.get()->getType(),
1974 SrcExpr.get(),
1975 /*IsLValueReference*/ false);
1976
1977 return TC_Success;
1978}
1979
1980// Checks for undefined behavior in reinterpret_cast.
1981// The cases that is checked for is:
1982// *reinterpret_cast<T*>(&a)
1983// reinterpret_cast<T&>(a)
1984// where accessing 'a' as type 'T' will result in undefined behavior.
1985void Sema::CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType,
1986 bool IsDereference,
1987 SourceRange Range) {
1988 unsigned DiagID = IsDereference ?
1989 diag::warn_pointer_indirection_from_incompatible_type :
1990 diag::warn_undefined_reinterpret_cast;
1991
1992 if (Diags.isIgnored(DiagID, Range.getBegin()))
1993 return;
1994
1995 QualType SrcTy, DestTy;
1996 if (IsDereference) {
1997 if (!SrcType->getAs<PointerType>() || !DestType->getAs<PointerType>()) {
1998 return;
1999 }
2000 SrcTy = SrcType->getPointeeType();
2001 DestTy = DestType->getPointeeType();
2002 } else {
2003 if (!DestType->getAs<ReferenceType>()) {
2004 return;
2005 }
2006 SrcTy = SrcType;
2007 DestTy = DestType->getPointeeType();
2008 }
2009
2010 // Cast is compatible if the types are the same.
2011 if (Context.hasSameUnqualifiedType(DestTy, SrcTy)) {
2012 return;
2013 }
2014 // or one of the types is a char or void type
2015 if (DestTy->isAnyCharacterType() || DestTy->isVoidType() ||
2016 SrcTy->isAnyCharacterType() || SrcTy->isVoidType()) {
2017 return;
2018 }
2019 // or one of the types is a tag type.
2020 if (SrcTy->getAs<TagType>() || DestTy->getAs<TagType>()) {
2021 return;
2022 }
2023
2024 // FIXME: Scoped enums?
2025 if ((SrcTy->isUnsignedIntegerType() && DestTy->isSignedIntegerType()) ||
2026 (SrcTy->isSignedIntegerType() && DestTy->isUnsignedIntegerType())) {
2027 if (Context.getTypeSize(DestTy) == Context.getTypeSize(SrcTy)) {
2028 return;
2029 }
2030 }
2031
2032 Diag(Range.getBegin(), DiagID) << SrcType << DestType << Range;
2033}
2034
2035static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr,
2036 QualType DestType) {
2037 QualType SrcType = SrcExpr.get()->getType();
2038 if (Self.Context.hasSameType(SrcType, DestType))
2039 return;
2040 if (const PointerType *SrcPtrTy = SrcType->getAs<PointerType>())
2041 if (SrcPtrTy->isObjCSelType()) {
2042 QualType DT = DestType;
2043 if (isa<PointerType>(DestType))
2044 DT = DestType->getPointeeType();
2045 if (!DT.getUnqualifiedType()->isVoidType())
2046 Self.Diag(SrcExpr.get()->getExprLoc(),
2047 diag::warn_cast_pointer_from_sel)
2048 << SrcType << DestType << SrcExpr.get()->getSourceRange();
2049 }
2050}
2051
2052/// Diagnose casts that change the calling convention of a pointer to a function
2053/// defined in the current TU.
2054static void DiagnoseCallingConvCast(Sema &Self, const ExprResult &SrcExpr,
2055 QualType DstType, SourceRange OpRange) {
2056 // Check if this cast would change the calling convention of a function
2057 // pointer type.
2058 QualType SrcType = SrcExpr.get()->getType();
2059 if (Self.Context.hasSameType(SrcType, DstType) ||
2060 !SrcType->isFunctionPointerType() || !DstType->isFunctionPointerType())
2061 return;
2062 const auto *SrcFTy =
2063 SrcType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
2064 const auto *DstFTy =
2065 DstType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
2066 CallingConv SrcCC = SrcFTy->getCallConv();
2067 CallingConv DstCC = DstFTy->getCallConv();
2068 if (SrcCC == DstCC)
2069 return;
2070
2071 // We have a calling convention cast. Check if the source is a pointer to a
2072 // known, specific function that has already been defined.
2073 Expr *Src = SrcExpr.get()->IgnoreParenImpCasts();
2074 if (auto *UO = dyn_cast<UnaryOperator>(Src))
2075 if (UO->getOpcode() == UO_AddrOf)
2076 Src = UO->getSubExpr()->IgnoreParenImpCasts();
2077 auto *DRE = dyn_cast<DeclRefExpr>(Src);
2078 if (!DRE)
2079 return;
2080 auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
2081 if (!FD)
2082 return;
2083
2084 // Only warn if we are casting from the default convention to a non-default
2085 // convention. This can happen when the programmer forgot to apply the calling
2086 // convention to the function declaration and then inserted this cast to
2087 // satisfy the type system.
2088 CallingConv DefaultCC = Self.getASTContext().getDefaultCallingConvention(
2089 FD->isVariadic(), FD->isCXXInstanceMember());
2090 if (DstCC == DefaultCC || SrcCC != DefaultCC)
2091 return;
2092
2093 // Diagnose this cast, as it is probably bad.
2094 StringRef SrcCCName = FunctionType::getNameForCallConv(SrcCC);
2095 StringRef DstCCName = FunctionType::getNameForCallConv(DstCC);
2096 Self.Diag(OpRange.getBegin(), diag::warn_cast_calling_conv)
2097 << SrcCCName << DstCCName << OpRange;
2098
2099 // The checks above are cheaper than checking if the diagnostic is enabled.
2100 // However, it's worth checking if the warning is enabled before we construct
2101 // a fixit.
2102 if (Self.Diags.isIgnored(diag::warn_cast_calling_conv, OpRange.getBegin()))
2103 return;
2104
2105 // Try to suggest a fixit to change the calling convention of the function
2106 // whose address was taken. Try to use the latest macro for the convention.
2107 // For example, users probably want to write "WINAPI" instead of "__stdcall"
2108 // to match the Windows header declarations.
2109 SourceLocation NameLoc = FD->getFirstDecl()->getNameInfo().getLoc();
2110 Preprocessor &PP = Self.getPreprocessor();
2111 SmallVector<TokenValue, 6> AttrTokens;
2112 SmallString<64> CCAttrText;
2113 llvm::raw_svector_ostream OS(CCAttrText);
2114 if (Self.getLangOpts().MicrosoftExt) {
2115 // __stdcall or __vectorcall
2116 OS << "__" << DstCCName;
2117 IdentifierInfo *II = PP.getIdentifierInfo(OS.str());
2118 AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
2119 ? TokenValue(II->getTokenID())
2120 : TokenValue(II));
2121 } else {
2122 // __attribute__((stdcall)) or __attribute__((vectorcall))
2123 OS << "__attribute__((" << DstCCName << "))";
2124 AttrTokens.push_back(tok::kw___attribute);
2125 AttrTokens.push_back(tok::l_paren);
2126 AttrTokens.push_back(tok::l_paren);
2127 IdentifierInfo *II = PP.getIdentifierInfo(DstCCName);
2128 AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
2129 ? TokenValue(II->getTokenID())
2130 : TokenValue(II));
2131 AttrTokens.push_back(tok::r_paren);
2132 AttrTokens.push_back(tok::r_paren);
2133 }
2134 StringRef AttrSpelling = PP.getLastMacroWithSpelling(NameLoc, AttrTokens);
2135 if (!AttrSpelling.empty())
2136 CCAttrText = AttrSpelling;
2137 OS << ' ';
2138 Self.Diag(NameLoc, diag::note_change_calling_conv_fixit)
2139 << FD << DstCCName << FixItHint::CreateInsertion(NameLoc, CCAttrText);
2140}
2141
2142static void checkIntToPointerCast(bool CStyle, const SourceRange &OpRange,
2143 const Expr *SrcExpr, QualType DestType,
2144 Sema &Self) {
2145 QualType SrcType = SrcExpr->getType();
2146
2147 // Not warning on reinterpret_cast, boolean, constant expressions, etc
2148 // are not explicit design choices, but consistent with GCC's behavior.
2149 // Feel free to modify them if you've reason/evidence for an alternative.
2150 if (CStyle && SrcType->isIntegralType(Self.Context)
2151 && !SrcType->isBooleanType()
2152 && !SrcType->isEnumeralType()
2153 && !SrcExpr->isIntegerConstantExpr(Self.Context)
2154 && Self.Context.getTypeSize(DestType) >
2155 Self.Context.getTypeSize(SrcType)) {
2156 // Separate between casts to void* and non-void* pointers.
2157 // Some APIs use (abuse) void* for something like a user context,
2158 // and often that value is an integer even if it isn't a pointer itself.
2159 // Having a separate warning flag allows users to control the warning
2160 // for their workflow.
2161 unsigned Diag = DestType->isVoidPointerType() ?
2162 diag::warn_int_to_void_pointer_cast
2163 : diag::warn_int_to_pointer_cast;
2164 Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
2165 }
2166}
2167
2168static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType,
2169 ExprResult &Result) {
2170 // We can only fix an overloaded reinterpret_cast if
2171 // - it is a template with explicit arguments that resolves to an lvalue
2172 // unambiguously, or
2173 // - it is the only function in an overload set that may have its address
2174 // taken.
2175
2176 Expr *E = Result.get();
2177 // TODO: what if this fails because of DiagnoseUseOfDecl or something
2178 // like it?
2179 if (Self.ResolveAndFixSingleFunctionTemplateSpecialization(
2180 Result,
2181 Expr::getValueKindForType(DestType) ==
2182 VK_PRValue // Convert Fun to Ptr
2183 ) &&
2184 Result.isUsable())
2185 return true;
2186
2187 // No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
2188 // preserves Result.
2189 Result = E;
2190 if (!Self.resolveAndFixAddressOfSingleOverloadCandidate(
2191 Result, /*DoFunctionPointerConversion=*/true))
2192 return false;
2193 return Result.isUsable();
2194}
2195
2196static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
2197 QualType DestType, bool CStyle,
2198 SourceRange OpRange,
2199 unsigned &msg,
2200 CastKind &Kind) {
2201 bool IsLValueCast = false;
2202
2203 DestType = Self.Context.getCanonicalType(DestType);
2204 QualType SrcType = SrcExpr.get()->getType();
2205
2206 // Is the source an overloaded name? (i.e. &foo)
2207 // If so, reinterpret_cast generally can not help us here (13.4, p1, bullet 5)
2208 if (SrcType == Self.Context.OverloadTy) {
2209 ExprResult FixedExpr = SrcExpr;
2210 if (!fixOverloadedReinterpretCastExpr(Self, DestType, FixedExpr))
2211 return TC_NotApplicable;
2212
2213 assert(FixedExpr.isUsable() && "Invalid result fixing overloaded expr")((void)0);
2214 SrcExpr = FixedExpr;
2215 SrcType = SrcExpr.get()->getType();
2216 }
2217
2218 if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
2219 if (!SrcExpr.get()->isGLValue()) {
2220 // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
2221 // similar comment in const_cast.
2222 msg = diag::err_bad_cxx_cast_rvalue;
2223 return TC_NotApplicable;
2224 }
2225
2226 if (!CStyle) {
2227 Self.CheckCompatibleReinterpretCast(SrcType, DestType,
2228 /*IsDereference=*/false, OpRange);
2229 }
2230
2231 // C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
2232 // same effect as the conversion *reinterpret_cast<T*>(&x) with the
2233 // built-in & and * operators.
2234
2235 const char *inappropriate = nullptr;
2236 switch (SrcExpr.get()->getObjectKind()) {
2237 case OK_Ordinary:
2238 break;
2239 case OK_BitField:
2240 msg = diag::err_bad_cxx_cast_bitfield;
2241 return TC_NotApplicable;
2242 // FIXME: Use a specific diagnostic for the rest of these cases.
2243 case OK_VectorComponent: inappropriate = "vector element"; break;
2244 case OK_MatrixComponent:
2245 inappropriate = "matrix element";
2246 break;
2247 case OK_ObjCProperty: inappropriate = "property expression"; break;
2248 case OK_ObjCSubscript: inappropriate = "container subscripting expression";
2249 break;
2250 }
2251 if (inappropriate) {
2252 Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
2253 << inappropriate << DestType
2254 << OpRange << SrcExpr.get()->getSourceRange();
2255 msg = 0; SrcExpr = ExprError();
2256 return TC_NotApplicable;
2257 }
2258
2259 // This code does this transformation for the checked types.
2260 DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
2261 SrcType = Self.Context.getPointerType(SrcType);
2262
2263 IsLValueCast = true;
2264 }
2265
2266 // Canonicalize source for comparison.
2267 SrcType = Self.Context.getCanonicalType(SrcType);
2268
2269 const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>(),
2270 *SrcMemPtr = SrcType->getAs<MemberPointerType>();
2271 if (DestMemPtr && SrcMemPtr) {
2272 // C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
2273 // can be explicitly converted to an rvalue of type "pointer to member
2274 // of Y of type T2" if T1 and T2 are both function types or both object
2275 // types.
2276 if (DestMemPtr->isMemberFunctionPointer() !=
2277 SrcMemPtr->isMemberFunctionPointer())
2278 return TC_NotApplicable;
2279
2280 if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2281 // We need to determine the inheritance model that the class will use if
2282 // haven't yet.
2283 (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
2284 (void)Self.isCompleteType(OpRange.getBegin(), DestType);
2285 }
2286
2287 // Don't allow casting between member pointers of different sizes.
2288 if (Self.Context.getTypeSize(DestMemPtr) !=
2289 Self.Context.getTypeSize(SrcMemPtr)) {
2290 msg = diag::err_bad_cxx_cast_member_pointer_size;
2291 return TC_Failed;
2292 }
2293
2294 // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
2295 // constness.
2296 // A reinterpret_cast followed by a const_cast can, though, so in C-style,
2297 // we accept it.
2298 if (auto CACK =
2299 CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2300 /*CheckObjCLifetime=*/CStyle))
2301 return getCastAwayConstnessCastKind(CACK, msg);
2302
2303 // A valid member pointer cast.
2304 assert(!IsLValueCast)((void)0);
2305 Kind = CK_ReinterpretMemberPointer;
2306 return TC_Success;
2307 }
2308
2309 // See below for the enumeral issue.
2310 if (SrcType->isNullPtrType() && DestType->isIntegralType(Self.Context)) {
2311 // C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
2312 // type large enough to hold it. A value of std::nullptr_t can be
2313 // converted to an integral type; the conversion has the same meaning
2314 // and validity as a conversion of (void*)0 to the integral type.
2315 if (Self.Context.getTypeSize(SrcType) >
2316 Self.Context.getTypeSize(DestType)) {
2317 msg = diag::err_bad_reinterpret_cast_small_int;
2318 return TC_Failed;
2319 }
2320 Kind = CK_PointerToIntegral;
2321 return TC_Success;
2322 }
2323
2324 // Allow reinterpret_casts between vectors of the same size and
2325 // between vectors and integers of the same size.
2326 bool destIsVector = DestType->isVectorType();
2327 bool srcIsVector = SrcType->isVectorType();
2328 if (srcIsVector || destIsVector) {
2329 // Allow bitcasting between SVE VLATs and VLSTs, and vice-versa.
2330 if (Self.isValidSveBitcast(SrcType, DestType)) {
2331 Kind = CK_BitCast;
2332 return TC_Success;
2333 }
2334
2335 // The non-vector type, if any, must have integral type. This is
2336 // the same rule that C vector casts use; note, however, that enum
2337 // types are not integral in C++.
2338 if ((!destIsVector && !DestType->isIntegralType(Self.Context)) ||
2339 (!srcIsVector && !SrcType->isIntegralType(Self.Context)))
2340 return TC_NotApplicable;
2341
2342 // The size we want to consider is eltCount * eltSize.
2343 // That's exactly what the lax-conversion rules will check.
2344 if (Self.areLaxCompatibleVectorTypes(SrcType, DestType)) {
2345 Kind = CK_BitCast;
2346 return TC_Success;
2347 }
2348
2349 if (Self.LangOpts.OpenCL && !CStyle) {
2350 if (DestType->isExtVectorType() || SrcType->isExtVectorType()) {
2351 // FIXME: Allow for reinterpret cast between 3 and 4 element vectors
2352 if (Self.areVectorTypesSameSize(SrcType, DestType)) {
2353 Kind = CK_BitCast;
2354 return TC_Success;
2355 }
2356 }
2357 }
2358
2359 // Otherwise, pick a reasonable diagnostic.
2360 if (!destIsVector)
2361 msg = diag::err_bad_cxx_cast_vector_to_scalar_different_size;
2362 else if (!srcIsVector)
2363 msg = diag::err_bad_cxx_cast_scalar_to_vector_different_size;
2364 else
2365 msg = diag::err_bad_cxx_cast_vector_to_vector_different_size;
2366
2367 return TC_Failed;
2368 }
2369
2370 if (SrcType == DestType) {
2371 // C++ 5.2.10p2 has a note that mentions that, subject to all other
2372 // restrictions, a cast to the same type is allowed so long as it does not
2373 // cast away constness. In C++98, the intent was not entirely clear here,
2374 // since all other paragraphs explicitly forbid casts to the same type.
2375 // C++11 clarifies this case with p2.
2376 //
2377 // The only allowed types are: integral, enumeration, pointer, or
2378 // pointer-to-member types. We also won't restrict Obj-C pointers either.
2379 Kind = CK_NoOp;
2380 TryCastResult Result = TC_NotApplicable;
2381 if (SrcType->isIntegralOrEnumerationType() ||
2382 SrcType->isAnyPointerType() ||
2383 SrcType->isMemberPointerType() ||
2384 SrcType->isBlockPointerType()) {
2385 Result = TC_Success;
2386 }
2387 return Result;
2388 }
2389
2390 bool destIsPtr = DestType->isAnyPointerType() ||
2391 DestType->isBlockPointerType();
2392 bool srcIsPtr = SrcType->isAnyPointerType() ||
2393 SrcType->isBlockPointerType();
2394 if (!destIsPtr && !srcIsPtr) {
2395 // Except for std::nullptr_t->integer and lvalue->reference, which are
2396 // handled above, at least one of the two arguments must be a pointer.
2397 return TC_NotApplicable;
2398 }
2399
2400 if (DestType->isIntegralType(Self.Context)) {
2401 assert(srcIsPtr && "One type must be a pointer")((void)0);
2402 // C++ 5.2.10p4: A pointer can be explicitly converted to any integral
2403 // type large enough to hold it; except in Microsoft mode, where the
2404 // integral type size doesn't matter (except we don't allow bool).
2405 if ((Self.Context.getTypeSize(SrcType) >
2406 Self.Context.getTypeSize(DestType))) {
2407 bool MicrosoftException =
2408 Self.getLangOpts().MicrosoftExt && !DestType->isBooleanType();
2409 if (MicrosoftException) {
2410 unsigned Diag = SrcType->isVoidPointerType()
2411 ? diag::warn_void_pointer_to_int_cast
2412 : diag::warn_pointer_to_int_cast;
2413 Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
2414 } else {
2415 msg = diag::err_bad_reinterpret_cast_small_int;
2416 return TC_Failed;
2417 }
2418 }
2419 Kind = CK_PointerToIntegral;
2420 return TC_Success;
2421 }
2422
2423 if (SrcType->isIntegralOrEnumerationType()) {
2424 assert(destIsPtr && "One type must be a pointer")((void)0);
2425 checkIntToPointerCast(CStyle, OpRange, SrcExpr.get(), DestType, Self);
2426 // C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
2427 // converted to a pointer.
2428 // C++ 5.2.10p9: [Note: ...a null pointer constant of integral type is not
2429 // necessarily converted to a null pointer value.]
2430 Kind = CK_IntegralToPointer;
2431 return TC_Success;
2432 }
2433
2434 if (!destIsPtr || !srcIsPtr) {
2435 // With the valid non-pointer conversions out of the way, we can be even
2436 // more stringent.
2437 return TC_NotApplicable;
2438 }
2439
2440 // Cannot convert between block pointers and Objective-C object pointers.
2441 if ((SrcType->isBlockPointerType() && DestType->isObjCObjectPointerType()) ||
2442 (DestType->isBlockPointerType() && SrcType->isObjCObjectPointerType()))
2443 return TC_NotApplicable;
2444
2445 // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
2446 // The C-style cast operator can.
2447 TryCastResult SuccessResult = TC_Success;
2448 if (auto CACK =
2449 CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
2450 /*CheckObjCLifetime=*/CStyle))
2451 SuccessResult = getCastAwayConstnessCastKind(CACK, msg);
2452
2453 if (IsAddressSpaceConversion(SrcType, DestType)) {
2454 Kind = CK_AddressSpaceConversion;
2455 assert(SrcType->isPointerType() && DestType->isPointerType())((void)0);
2456 if (!CStyle &&
2457 !DestType->getPointeeType().getQualifiers().isAddressSpaceSupersetOf(
2458 SrcType->getPointeeType().getQualifiers())) {
2459 SuccessResult = TC_Failed;
2460 }
2461 } else if (IsLValueCast) {
2462 Kind = CK_LValueBitCast;
2463 } else if (DestType->isObjCObjectPointerType()) {
2464 Kind = Self.PrepareCastToObjCObjectPointer(SrcExpr);
2465 } else if (DestType->isBlockPointerType()) {
2466 if (!SrcType->isBlockPointerType()) {
2467 Kind = CK_AnyPointerToBlockPointerCast;
2468 } else {
2469 Kind = CK_BitCast;
2470 }
2471 } else {
2472 Kind = CK_BitCast;
2473 }
2474
2475 // Any pointer can be cast to an Objective-C pointer type with a C-style
2476 // cast.
2477 if (CStyle && DestType->isObjCObjectPointerType()) {
2478 return SuccessResult;
2479 }
2480 if (CStyle)
2481 DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2482
2483 DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
2484
2485 // Not casting away constness, so the only remaining check is for compatible
2486 // pointer categories.
2487
2488 if (SrcType->isFunctionPointerType()) {
2489 if (DestType->isFunctionPointerType()) {
2490 // C++ 5.2.10p6: A pointer to a function can be explicitly converted to
2491 // a pointer to a function of a different type.
2492 return SuccessResult;
2493 }
2494
2495 // C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
2496 // an object type or vice versa is conditionally-supported.
2497 // Compilers support it in C++03 too, though, because it's necessary for
2498 // casting the return value of dlsym() and GetProcAddress().
2499 // FIXME: Conditionally-supported behavior should be configurable in the
2500 // TargetInfo or similar.
2501 Self.Diag(OpRange.getBegin(),
2502 Self.getLangOpts().CPlusPlus11 ?
2503 diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2504 << OpRange;
2505 return SuccessResult;
2506 }
2507
2508 if (DestType->isFunctionPointerType()) {
2509 // See above.
2510 Self.Diag(OpRange.getBegin(),
2511 Self.getLangOpts().CPlusPlus11 ?
2512 diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
2513 << OpRange;
2514 return SuccessResult;
2515 }
2516
2517 // Diagnose address space conversion in nested pointers.
2518 QualType DestPtee = DestType->getPointeeType().isNull()
2519 ? DestType->getPointeeType()
2520 : DestType->getPointeeType()->getPointeeType();
2521 QualType SrcPtee = SrcType->getPointeeType().isNull()
2522 ? SrcType->getPointeeType()
2523 : SrcType->getPointeeType()->getPointeeType();
2524 while (!DestPtee.isNull() && !SrcPtee.isNull()) {
2525 if (DestPtee.getAddressSpace() != SrcPtee.getAddressSpace()) {
2526 Self.Diag(OpRange.getBegin(),
2527 diag::warn_bad_cxx_cast_nested_pointer_addr_space)
2528 << CStyle << SrcType << DestType << SrcExpr.get()->getSourceRange();
2529 break;
2530 }
2531 DestPtee = DestPtee->getPointeeType();
2532 SrcPtee = SrcPtee->getPointeeType();
2533 }
2534
2535 // C++ 5.2.10p7: A pointer to an object can be explicitly converted to
2536 // a pointer to an object of different type.
2537 // Void pointers are not specified, but supported by every compiler out there.
2538 // So we finish by allowing everything that remains - it's got to be two
2539 // object pointers.
2540 return SuccessResult;
2541}
2542
2543static TryCastResult TryAddressSpaceCast(Sema &Self, ExprResult &SrcExpr,
2544 QualType DestType, bool CStyle,
2545 unsigned &msg, CastKind &Kind) {
2546 if (!Self.getLangOpts().OpenCL)
2547 // FIXME: As compiler doesn't have any information about overlapping addr
2548 // spaces at the moment we have to be permissive here.
2549 return TC_NotApplicable;
2550 // Even though the logic below is general enough and can be applied to
2551 // non-OpenCL mode too, we fast-path above because no other languages
2552 // define overlapping address spaces currently.
2553 auto SrcType = SrcExpr.get()->getType();
2554 // FIXME: Should this be generalized to references? The reference parameter
2555 // however becomes a reference pointee type here and therefore rejected.
2556 // Perhaps this is the right behavior though according to C++.
2557 auto SrcPtrType = SrcType->getAs<PointerType>();
2558 if (!SrcPtrType)
2559 return TC_NotApplicable;
2560 auto DestPtrType = DestType->getAs<PointerType>();
2561 if (!DestPtrType)
2562 return TC_NotApplicable;
2563 auto SrcPointeeType = SrcPtrType->getPointeeType();
2564 auto DestPointeeType = DestPtrType->getPointeeType();
2565 if (!DestPointeeType.isAddressSpaceOverlapping(SrcPointeeType)) {
2566 msg = diag::err_bad_cxx_cast_addr_space_mismatch;
2567 return TC_Failed;
2568 }
2569 auto SrcPointeeTypeWithoutAS =
2570 Self.Context.removeAddrSpaceQualType(SrcPointeeType.getCanonicalType());
2571 auto DestPointeeTypeWithoutAS =
2572 Self.Context.removeAddrSpaceQualType(DestPointeeType.getCanonicalType());
2573 if (Self.Context.hasSameType(SrcPointeeTypeWithoutAS,
2574 DestPointeeTypeWithoutAS)) {
2575 Kind = SrcPointeeType.getAddressSpace() == DestPointeeType.getAddressSpace()
2576 ? CK_NoOp
2577 : CK_AddressSpaceConversion;
2578 return TC_Success;
2579 } else {
2580 return TC_NotApplicable;
2581 }
2582}
2583
2584void CastOperation::checkAddressSpaceCast(QualType SrcType, QualType DestType) {
2585 // In OpenCL only conversions between pointers to objects in overlapping
2586 // addr spaces are allowed. v2.0 s6.5.5 - Generic addr space overlaps
2587 // with any named one, except for constant.
2588
2589 // Converting the top level pointee addrspace is permitted for compatible
2590 // addrspaces (such as 'generic int *' to 'local int *' or vice versa), but
2591 // if any of the nested pointee addrspaces differ, we emit a warning
2592 // regardless of addrspace compatibility. This makes
2593 // local int ** p;
2594 // return (generic int **) p;
2595 // warn even though local -> generic is permitted.
2596 if (Self.getLangOpts().OpenCL) {
2597 const Type *DestPtr, *SrcPtr;
2598 bool Nested = false;
2599 unsigned DiagID = diag::err_typecheck_incompatible_address_space;
2600 DestPtr = Self.getASTContext().getCanonicalType(DestType.getTypePtr()),
2601 SrcPtr = Self.getASTContext().getCanonicalType(SrcType.getTypePtr());
2602
2603 while (isa<PointerType>(DestPtr) && isa<PointerType>(SrcPtr)) {
2604 const PointerType *DestPPtr = cast<PointerType>(DestPtr);
2605 const PointerType *SrcPPtr = cast<PointerType>(SrcPtr);
2606 QualType DestPPointee = DestPPtr->getPointeeType();
2607 QualType SrcPPointee = SrcPPtr->getPointeeType();
2608 if (Nested
2609 ? DestPPointee.getAddressSpace() != SrcPPointee.getAddressSpace()
2610 : !DestPPointee.isAddressSpaceOverlapping(SrcPPointee)) {
2611 Self.Diag(OpRange.getBegin(), DiagID)
2612 << SrcType << DestType << Sema::AA_Casting
2613 << SrcExpr.get()->getSourceRange();
2614 if (!Nested)
2615 SrcExpr = ExprError();
2616 return;
2617 }
2618
2619 DestPtr = DestPPtr->getPointeeType().getTypePtr();
2620 SrcPtr = SrcPPtr->getPointeeType().getTypePtr();
2621 Nested = true;
2622 DiagID = diag::ext_nested_pointer_qualifier_mismatch;
2623 }
2624 }
2625}
2626
2627bool Sema::ShouldSplatAltivecScalarInCast(const VectorType *VecTy) {
2628 bool SrcCompatXL = this->getLangOpts().getAltivecSrcCompat() ==
2629 LangOptions::AltivecSrcCompatKind::XL;
2630 VectorType::VectorKind VKind = VecTy->getVectorKind();
2631
2632 if ((VKind == VectorType::AltiVecVector) ||
2633 (SrcCompatXL && ((VKind == VectorType::AltiVecBool) ||
2634 (VKind == VectorType::AltiVecPixel)))) {
2635 return true;
2636 }
2637 return false;
2638}
2639
2640void CastOperation::CheckCXXCStyleCast(bool FunctionalStyle,
2641 bool ListInitialization) {
2642 assert(Self.getLangOpts().CPlusPlus)((void)0);
2643
2644 // Handle placeholders.
2645 if (isPlaceholder()) {
2646 // C-style casts can resolve __unknown_any types.
2647 if (claimPlaceholder(BuiltinType::UnknownAny)) {
2648 SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2649 SrcExpr.get(), Kind,
2650 ValueKind, BasePath);
2651 return;
2652 }
2653
2654 checkNonOverloadPlaceholders();
2655 if (SrcExpr.isInvalid())
2656 return;
2657 }
2658
2659 // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
2660 // This test is outside everything else because it's the only case where
2661 // a non-lvalue-reference target type does not lead to decay.
2662 if (DestType->isVoidType()) {
2663 Kind = CK_ToVoid;
2664
2665 if (claimPlaceholder(BuiltinType::Overload)) {
2666 Self.ResolveAndFixSingleFunctionTemplateSpecialization(
2667 SrcExpr, /* Decay Function to ptr */ false,
2668 /* Complain */ true, DestRange, DestType,
2669 diag::err_bad_cstyle_cast_overload);
2670 if (SrcExpr.isInvalid())
2671 return;
2672 }
2673
2674 SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2675 return;
2676 }
2677
2678 // If the type is dependent, we won't do any other semantic analysis now.
2679 if (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
2680 SrcExpr.get()->isValueDependent()) {
2681 assert(Kind == CK_Dependent)((void)0);
2682 return;
2683 }
2684
2685 if (ValueKind == VK_PRValue && !DestType->isRecordType() &&
2686 !isPlaceholder(BuiltinType::Overload)) {
2687 SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2688 if (SrcExpr.isInvalid())
2689 return;
2690 }
2691
2692 // AltiVec vector initialization with a single literal.
2693 if (const VectorType *vecTy = DestType->getAs<VectorType>())
2694 if (Self.ShouldSplatAltivecScalarInCast(vecTy) &&
2695 (SrcExpr.get()->getType()->isIntegerType() ||
2696 SrcExpr.get()->getType()->isFloatingType())) {
2697 Kind = CK_VectorSplat;
2698 SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2699 return;
2700 }
2701
2702 // C++ [expr.cast]p5: The conversions performed by
2703 // - a const_cast,
2704 // - a static_cast,
2705 // - a static_cast followed by a const_cast,
2706 // - a reinterpret_cast, or
2707 // - a reinterpret_cast followed by a const_cast,
2708 // can be performed using the cast notation of explicit type conversion.
2709 // [...] If a conversion can be interpreted in more than one of the ways
2710 // listed above, the interpretation that appears first in the list is used,
2711 // even if a cast resulting from that interpretation is ill-formed.
2712 // In plain language, this means trying a const_cast ...
2713 // Note that for address space we check compatibility after const_cast.
2714 unsigned msg = diag::err_bad_cxx_cast_generic;
2715 TryCastResult tcr = TryConstCast(Self, SrcExpr, DestType,
2716 /*CStyle*/ true, msg);
2717 if (SrcExpr.isInvalid())
2718 return;
2719 if (isValidCast(tcr))
2720 Kind = CK_NoOp;
2721
2722 Sema::CheckedConversionKind CCK =
2723 FunctionalStyle ? Sema::CCK_FunctionalCast : Sema::CCK_CStyleCast;
2724 if (tcr == TC_NotApplicable) {
2725 tcr = TryAddressSpaceCast(Self, SrcExpr, DestType, /*CStyle*/ true, msg,
2726 Kind);
2727 if (SrcExpr.isInvalid())
2728 return;
2729
2730 if (tcr == TC_NotApplicable) {
2731 // ... or if that is not possible, a static_cast, ignoring const and
2732 // addr space, ...
2733 tcr = TryStaticCast(Self, SrcExpr, DestType, CCK, OpRange, msg, Kind,
2734 BasePath, ListInitialization);
2735 if (SrcExpr.isInvalid())
2736 return;
2737
2738 if (tcr == TC_NotApplicable) {
2739 // ... and finally a reinterpret_cast, ignoring const and addr space.
2740 tcr = TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/ true,
2741 OpRange, msg, Kind);
2742 if (SrcExpr.isInvalid())
2743 return;
2744 }
2745 }
2746 }
2747
2748 if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
2749 isValidCast(tcr))
2750 checkObjCConversion(CCK);
2751
2752 if (tcr != TC_Success && msg != 0) {
2753 if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2754 DeclAccessPair Found;
2755 FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
2756 DestType,
2757 /*Complain*/ true,
2758 Found);
2759 if (Fn) {
2760 // If DestType is a function type (not to be confused with the function
2761 // pointer type), it will be possible to resolve the function address,
2762 // but the type cast should be considered as failure.
2763 OverloadExpr *OE = OverloadExpr::find(SrcExpr.get()).Expression;
2764 Self.Diag(OpRange.getBegin(), diag::err_bad_cstyle_cast_overload)
2765 << OE->getName() << DestType << OpRange
2766 << OE->getQualifierLoc().getSourceRange();
2767 Self.NoteAllOverloadCandidates(SrcExpr.get());
2768 }
2769 } else {
2770 diagnoseBadCast(Self, msg, (FunctionalStyle ? CT_Functional : CT_CStyle),
2771 OpRange, SrcExpr.get(), DestType, ListInitialization);
2772 }
2773 }
2774
2775 if (isValidCast(tcr)) {
2776 if (Kind == CK_BitCast)
2777 checkCastAlign();
2778
2779 if (!checkCastFunctionType(Self, SrcExpr, DestType))
2780 Self.Diag(OpRange.getBegin(), diag::warn_cast_function_type)
2781 << SrcExpr.get()->getType() << DestType << OpRange;
2782
2783 } else {
2784 SrcExpr = ExprError();
2785 }
2786}
2787
2788/// DiagnoseBadFunctionCast - Warn whenever a function call is cast to a
2789/// non-matching type. Such as enum function call to int, int call to
2790/// pointer; etc. Cast to 'void' is an exception.
2791static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr,
2792 QualType DestType) {
2793 if (Self.Diags.isIgnored(diag::warn_bad_function_cast,
2794 SrcExpr.get()->getExprLoc()))
2795 return;
2796
2797 if (!isa<CallExpr>(SrcExpr.get()))
2798 return;
2799
2800 QualType SrcType = SrcExpr.get()->getType();
2801 if (DestType.getUnqualifiedType()->isVoidType())
2802 return;
2803 if ((SrcType->isAnyPointerType() || SrcType->isBlockPointerType())
2804 && (DestType->isAnyPointerType() || DestType->isBlockPointerType()))
2805 return;
2806 if (SrcType->isIntegerType() && DestType->isIntegerType() &&
2807 (SrcType->isBooleanType() == DestType->isBooleanType()) &&
2808 (SrcType->isEnumeralType() == DestType->isEnumeralType()))
2809 return;
2810 if (SrcType->isRealFloatingType() && DestType->isRealFloatingType())
2811 return;
2812 if (SrcType->isEnumeralType() && DestType->isEnumeralType())
2813 return;
2814 if (SrcType->isComplexType() && DestType->isComplexType())
2815 return;
2816 if (SrcType->isComplexIntegerType() && DestType->isComplexIntegerType())
2817 return;
2818 if (SrcType->isFixedPointType() && DestType->isFixedPointType())
2819 return;
2820
2821 Self.Diag(SrcExpr.get()->getExprLoc(),
2822 diag::warn_bad_function_cast)
2823 << SrcType << DestType << SrcExpr.get()->getSourceRange();
2824}
2825
2826/// Check the semantics of a C-style cast operation, in C.
2827void CastOperation::CheckCStyleCast() {
2828 assert(!Self.getLangOpts().CPlusPlus)((void)0);
2829
2830 // C-style casts can resolve __unknown_any types.
2831 if (claimPlaceholder(BuiltinType::UnknownAny)) {
2832 SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2833 SrcExpr.get(), Kind,
2834 ValueKind, BasePath);
2835 return;
2836 }
2837
2838 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression
2839 // type needs to be scalar.
2840 if (DestType->isVoidType()) {
2841 // We don't necessarily do lvalue-to-rvalue conversions on this.
2842 SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2843 if (SrcExpr.isInvalid())
2844 return;
2845
2846 // Cast to void allows any expr type.
2847 Kind = CK_ToVoid;
2848 return;
2849 }
2850
2851 // If the type is dependent, we won't do any other semantic analysis now.
2852 if (Self.getASTContext().isDependenceAllowed() &&
2853 (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
2854 SrcExpr.get()->isValueDependent())) {
2855 assert((DestType->containsErrors() || SrcExpr.get()->containsErrors() ||((void)0)
2856 SrcExpr.get()->containsErrors()) &&((void)0)
2857 "should only occur in error-recovery path.")((void)0);
2858 assert(Kind == CK_Dependent)((void)0);
2859 return;
2860 }
2861
2862 // Overloads are allowed with C extensions, so we need to support them.
2863 if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2864 DeclAccessPair DAP;
2865 if (FunctionDecl *FD = Self.ResolveAddressOfOverloadedFunction(
2866 SrcExpr.get(), DestType, /*Complain=*/true, DAP))
2867 SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr.get(), DAP, FD);
2868 else
2869 return;
2870 assert(SrcExpr.isUsable())((void)0);
2871 }
2872 SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2873 if (SrcExpr.isInvalid())
2874 return;
2875 QualType SrcType = SrcExpr.get()->getType();
2876
2877 assert(!SrcType->isPlaceholderType())((void)0);
2878
2879 checkAddressSpaceCast(SrcType, DestType);
2880 if (SrcExpr.isInvalid())
2881 return;
2882
2883 if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
2884 diag::err_typecheck_cast_to_incomplete)) {
2885 SrcExpr = ExprError();
2886 return;
2887 }
2888
2889 // Allow casting a sizeless built-in type to itself.
2890 if (DestType->isSizelessBuiltinType() &&
2891 Self.Context.hasSameUnqualifiedType(DestType, SrcType)) {
2892 Kind = CK_NoOp;
2893 return;
2894 }
2895
2896 // Allow bitcasting between compatible SVE vector types.
2897 if ((SrcType->isVectorType() || DestType->isVectorType()) &&
2898 Self.isValidSveBitcast(SrcType, DestType)) {
2899 Kind = CK_BitCast;
2900 return;
2901 }
2902
2903 if (!DestType->isScalarType() && !DestType->isVectorType() &&
2904 !DestType->isMatrixType()) {
2905 const RecordType *DestRecordTy = DestType->getAs<RecordType>();
2906
2907 if (DestRecordTy && Self.Context.hasSameUnqualifiedType(DestType, SrcType)){
2908 // GCC struct/union extension: allow cast to self.
2909 Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_nonscalar)
2910 << DestType << SrcExpr.get()->getSourceRange();
2911 Kind = CK_NoOp;
2912 return;
2913 }
2914
2915 // GCC's cast to union extension.
2916 if (DestRecordTy && DestRecordTy->getDecl()->isUnion()) {
2917 RecordDecl *RD = DestRecordTy->getDecl();
2918 if (CastExpr::getTargetFieldForToUnionCast(RD, SrcType)) {
2919 Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_to_union)
2920 << SrcExpr.get()->getSourceRange();
2921 Kind = CK_ToUnion;
2922 return;
2923 } else {
2924 Self.Diag(OpRange.getBegin(), diag::err_typecheck_cast_to_union_no_type)
2925 << SrcType << SrcExpr.get()->getSourceRange();
2926 SrcExpr = ExprError();
2927 return;
2928 }
2929 }
2930
2931 // OpenCL v2.0 s6.13.10 - Allow casts from '0' to event_t type.
2932 if (Self.getLangOpts().OpenCL && DestType->isEventT()) {
2933 Expr::EvalResult Result;
2934 if (SrcExpr.get()->EvaluateAsInt(Result, Self.Context)) {
2935 llvm::APSInt CastInt = Result.Val.getInt();
2936 if (0 == CastInt) {
2937 Kind = CK_ZeroToOCLOpaqueType;
2938 return;
2939 }
2940 Self.Diag(OpRange.getBegin(),
2941 diag::err_opencl_cast_non_zero_to_event_t)
2942 << toString(CastInt, 10) << SrcExpr.get()->getSourceRange();
2943 SrcExpr = ExprError();
2944 return;
2945 }
2946 }
2947
2948 // Reject any other conversions to non-scalar types.
2949 Self.Diag(OpRange.getBegin(), diag::err_typecheck_cond_expect_scalar)
2950 << DestType << SrcExpr.get()->getSourceRange();
2951 SrcExpr = ExprError();
2952 return;
2953 }
2954
2955 // The type we're casting to is known to be a scalar, a vector, or a matrix.
2956
2957 // Require the operand to be a scalar, a vector, or a matrix.
2958 if (!SrcType->isScalarType() && !SrcType->isVectorType() &&
2959 !SrcType->isMatrixType()) {
2960 Self.Diag(SrcExpr.get()->getExprLoc(),
2961 diag::err_typecheck_expect_scalar_operand)
2962 << SrcType << SrcExpr.get()->getSourceRange();
2963 SrcExpr = ExprError();
2964 return;
2965 }
2966
2967 if (DestType->isExtVectorType()) {
2968 SrcExpr = Self.CheckExtVectorCast(OpRange, DestType, SrcExpr.get(), Kind);
2969 return;
2970 }
2971
2972 if (DestType->getAs<MatrixType>() || SrcType->getAs<MatrixType>()) {
2973 if (Self.CheckMatrixCast(OpRange, DestType, SrcType, Kind))
2974 SrcExpr = ExprError();
2975 return;
2976 }
2977
2978 if (const VectorType *DestVecTy = DestType->getAs<VectorType>()) {
2979 if (Self.ShouldSplatAltivecScalarInCast(DestVecTy) &&
2980 (SrcType->isIntegerType() || SrcType->isFloatingType())) {
2981 Kind = CK_VectorSplat;
2982 SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
2983 } else if (Self.CheckVectorCast(OpRange, DestType, SrcType, Kind)) {
2984 SrcExpr = ExprError();
2985 }
2986 return;
2987 }
2988
2989 if (SrcType->isVectorType()) {
2990 if (Self.CheckVectorCast(OpRange, SrcType, DestType, Kind))
2991 SrcExpr = ExprError();
2992 return;
2993 }
2994
2995 // The source and target types are both scalars, i.e.
2996 // - arithmetic types (fundamental, enum, and complex)
2997 // - all kinds of pointers
2998 // Note that member pointers were filtered out with C++, above.
2999
3000 if (isa<ObjCSelectorExpr>(SrcExpr.get())) {
3001 Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_selector_expr);
3002 SrcExpr = ExprError();
3003 return;
3004 }
3005
3006 // Can't cast to or from bfloat
3007 if (DestType->isBFloat16Type() && !SrcType->isBFloat16Type()) {
3008 Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_to_bfloat16)
3009 << SrcExpr.get()->getSourceRange();
3010 SrcExpr = ExprError();
3011 return;
3012 }
3013 if (SrcType->isBFloat16Type() && !DestType->isBFloat16Type()) {
3014 Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_from_bfloat16)
3015 << SrcExpr.get()->getSourceRange();
3016 SrcExpr = ExprError();
3017 return;
3018 }
3019
3020 // If either type is a pointer, the other type has to be either an
3021 // integer or a pointer.
3022 if (!DestType->isArithmeticType()) {
3023 if (!SrcType->isIntegralType(Self.Context) && SrcType->isArithmeticType()) {
3024 Self.Diag(SrcExpr.get()->getExprLoc(),
3025 diag::err_cast_pointer_from_non_pointer_int)
3026 << SrcType << SrcExpr.get()->getSourceRange();
3027 SrcExpr = ExprError();
3028 return;
3029 }
3030 checkIntToPointerCast(/* CStyle */ true, OpRange, SrcExpr.get(), DestType,
3031 Self);
3032 } else if (!SrcType->isArithmeticType()) {
3033 if (!DestType->isIntegralType(Self.Context) &&
3034 DestType->isArithmeticType()) {
3035 Self.Diag(SrcExpr.get()->getBeginLoc(),
3036 diag::err_cast_pointer_to_non_pointer_int)
3037 << DestType << SrcExpr.get()->getSourceRange();
3038 SrcExpr = ExprError();
3039 return;
3040 }
3041
3042 if ((Self.Context.getTypeSize(SrcType) >
3043 Self.Context.getTypeSize(DestType)) &&
3044 !DestType->isBooleanType()) {
3045 // C 6.3.2.3p6: Any pointer type may be converted to an integer type.
3046 // Except as previously specified, the result is implementation-defined.
3047 // If the result cannot be represented in the integer type, the behavior
3048 // is undefined. The result need not be in the range of values of any
3049 // integer type.
3050 unsigned Diag;
3051 if (SrcType->isVoidPointerType())
3052 Diag = DestType->isEnumeralType() ? diag::warn_void_pointer_to_enum_cast
3053 : diag::warn_void_pointer_to_int_cast;
3054 else if (DestType->isEnumeralType())
3055 Diag = diag::warn_pointer_to_enum_cast;
3056 else
3057 Diag = diag::warn_pointer_to_int_cast;
3058 Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
3059 }
3060 }
3061
3062 if (Self.getLangOpts().OpenCL && !Self.getOpenCLOptions().isAvailableOption(
3063 "cl_khr_fp16", Self.getLangOpts())) {
3064 if (DestType->isHalfType()) {
3065 Self.Diag(SrcExpr.get()->getBeginLoc(), diag::err_opencl_cast_to_half)
3066 << DestType << SrcExpr.get()->getSourceRange();
3067 SrcExpr = ExprError();
3068 return;
3069 }
3070 }
3071
3072 // ARC imposes extra restrictions on casts.
3073 if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers()) {
3074 checkObjCConversion(Sema::CCK_CStyleCast);
3075 if (SrcExpr.isInvalid())
3076 return;
3077
3078 const PointerType *CastPtr = DestType->getAs<PointerType>();
3079 if (Self.getLangOpts().ObjCAutoRefCount && CastPtr) {
3080 if (const PointerType *ExprPtr = SrcType->getAs<PointerType>()) {
3081 Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers();
3082 Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers();
3083 if (CastPtr->getPointeeType()->isObjCLifetimeType() &&
3084 ExprPtr->getPointeeType()->isObjCLifetimeType() &&
3085 !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) {
3086 Self.Diag(SrcExpr.get()->getBeginLoc(),
3087 diag::err_typecheck_incompatible_ownership)
3088 << SrcType << DestType << Sema::AA_Casting
3089 << SrcExpr.get()->getSourceRange();
3090 return;
3091 }
3092 }
3093 }
3094 else if (!Self.CheckObjCARCUnavailableWeakConversion(DestType, SrcType)) {
3095 Self.Diag(SrcExpr.get()->getBeginLoc(),
3096 diag::err_arc_convesion_of_weak_unavailable)
3097 << 1 << SrcType << DestType << SrcExpr.get()->getSourceRange();
3098 SrcExpr = ExprError();
3099 return;
3100 }
3101 }
3102
3103 if (!checkCastFunctionType(Self, SrcExpr, DestType))
3104 Self.Diag(OpRange.getBegin(), diag::warn_cast_function_type)
3105 << SrcType << DestType << OpRange;
3106
3107 DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
3108 DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
3109 DiagnoseBadFunctionCast(Self, SrcExpr, DestType);
3110 Kind = Self.PrepareScalarCast(SrcExpr, DestType);
3111 if (SrcExpr.isInvalid())
3112 return;
3113
3114 if (Kind == CK_BitCast)
3115 checkCastAlign();
3116}
3117
3118void CastOperation::CheckBuiltinBitCast() {
3119 QualType SrcType = SrcExpr.get()->getType();
3120
3121 if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
3122 diag::err_typecheck_cast_to_incomplete) ||
3123 Self.RequireCompleteType(OpRange.getBegin(), SrcType,
3124 diag::err_incomplete_type)) {
3125 SrcExpr = ExprError();
3126 return;
3127 }
3128
3129 if (SrcExpr.get()->isPRValue())
3130 SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcType, SrcExpr.get(),
3131 /*IsLValueReference=*/false);
3132
3133 CharUnits DestSize = Self.Context.getTypeSizeInChars(DestType);
3134 CharUnits SourceSize = Self.Context.getTypeSizeInChars(SrcType);
3135 if (DestSize != SourceSize) {
3136 Self.Diag(OpRange.getBegin(), diag::err_bit_cast_type_size_mismatch)
3137 << (int)SourceSize.getQuantity() << (int)DestSize.getQuantity();
3138 SrcExpr = ExprError();
3139 return;
3140 }
3141
3142 if (!DestType.isTriviallyCopyableType(Self.Context)) {
3143 Self.Diag(OpRange.getBegin(), diag::err_bit_cast_non_trivially_copyable)
3144 << 1;
3145 SrcExpr = ExprError();
3146 return;
3147 }
3148
3149 if (!SrcType.isTriviallyCopyableType(Self.Context)) {
3150 Self.Diag(OpRange.getBegin(), diag::err_bit_cast_non_trivially_copyable)
3151 << 0;
3152 SrcExpr = ExprError();
3153 return;
3154 }
3155
3156 Kind = CK_LValueToRValueBitCast;
3157}
3158
3159/// DiagnoseCastQual - Warn whenever casts discards a qualifiers, be it either
3160/// const, volatile or both.
3161static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
3162 QualType DestType) {
3163 if (SrcExpr.isInvalid())
3164 return;
3165
3166 QualType SrcType = SrcExpr.get()->getType();
3167 if (!((SrcType->isAnyPointerType() && DestType->isAnyPointerType()) ||
3168 DestType->isLValueReferenceType()))
3169 return;
3170
3171 QualType TheOffendingSrcType, TheOffendingDestType;
3172 Qualifiers CastAwayQualifiers;
3173 if (CastsAwayConstness(Self, SrcType, DestType, true, false,
3174 &TheOffendingSrcType, &TheOffendingDestType,
3175 &CastAwayQualifiers) !=
3176 CastAwayConstnessKind::CACK_Similar)
3177 return;
3178
3179 // FIXME: 'restrict' is not properly handled here.
3180 int qualifiers = -1;
3181 if (CastAwayQualifiers.hasConst() && CastAwayQualifiers.hasVolatile()) {
3182 qualifiers = 0;
3183 } else if (CastAwayQualifiers.hasConst()) {
3184 qualifiers = 1;
3185 } else if (CastAwayQualifiers.hasVolatile()) {
3186 qualifiers = 2;
3187 }
3188 // This is a variant of int **x; const int **y = (const int **)x;
3189 if (qualifiers == -1)
3190 Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual2)
3191 << SrcType << DestType;
3192 else
3193 Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual)
3194 << TheOffendingSrcType << TheOffendingDestType << qualifiers;
3195}
3196
3197ExprResult Sema::BuildCStyleCastExpr(SourceLocation LPLoc,
3198 TypeSourceInfo *CastTypeInfo,
3199 SourceLocation RPLoc,
3200 Expr *CastExpr) {
3201 CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
3202 Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
3203 Op.OpRange = SourceRange(LPLoc, CastExpr->getEndLoc());
3204
3205 if (getLangOpts().CPlusPlus) {
3206 Op.CheckCXXCStyleCast(/*FunctionalCast=*/ false,
3207 isa<InitListExpr>(CastExpr));
3208 } else {
3209 Op.CheckCStyleCast();
3210 }
3211
3212 if (Op.SrcExpr.isInvalid())
3213 return ExprError();
3214
3215 // -Wcast-qual
3216 DiagnoseCastQual(Op.Self, Op.SrcExpr, Op.DestType);
3217
3218 return Op.complete(CStyleCastExpr::Create(
3219 Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
3220 &Op.BasePath, CurFPFeatureOverrides(), CastTypeInfo, LPLoc, RPLoc));
3221}
3222
3223ExprResult Sema::BuildCXXFunctionalCastExpr(TypeSourceInfo *CastTypeInfo,
3224 QualType Type,
3225 SourceLocation LPLoc,
3226 Expr *CastExpr,
3227 SourceLocation RPLoc) {
3228 assert(LPLoc.isValid() && "List-initialization shouldn't get here.")((void)0);
3229 CastOperation Op(*this, Type, CastExpr);
3230 Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
3231 Op.OpRange = SourceRange(Op.DestRange.getBegin(), CastExpr->getEndLoc());
3232
3233 Op.CheckCXXCStyleCast(/*FunctionalCast=*/true, /*ListInit=*/false);
3234 if (Op.SrcExpr.isInvalid())
3235 return ExprError();
3236
3237 auto *SubExpr = Op.SrcExpr.get();
3238 if (auto *BindExpr = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
3239 SubExpr = BindExpr->getSubExpr();
3240 if (auto *ConstructExpr = dyn_cast<CXXConstructExpr>(SubExpr))
3241 ConstructExpr->setParenOrBraceRange(SourceRange(LPLoc, RPLoc));
3242
3243 return Op.complete(CXXFunctionalCastExpr::Create(
3244 Context, Op.ResultType, Op.ValueKind, CastTypeInfo, Op.Kind,
3245 Op.SrcExpr.get(), &Op.BasePath, CurFPFeatureOverrides(), LPLoc, RPLoc));
3246}

/usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/include/clang/AST/Type.h

1//===- Type.h - C Language Family Type Representation -----------*- C++ -*-===//
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/// \file
10/// C Language Family Type Representation
11///
12/// This file defines the clang::Type interface and subclasses, used to
13/// represent types for languages in the C family.
14//
15//===----------------------------------------------------------------------===//
16
17#ifndef LLVM_CLANG_AST_TYPE_H
18#define LLVM_CLANG_AST_TYPE_H
19
20#include "clang/AST/DependenceFlags.h"
21#include "clang/AST/NestedNameSpecifier.h"
22#include "clang/AST/TemplateName.h"
23#include "clang/Basic/AddressSpaces.h"
24#include "clang/Basic/AttrKinds.h"
25#include "clang/Basic/Diagnostic.h"
26#include "clang/Basic/ExceptionSpecificationType.h"
27#include "clang/Basic/LLVM.h"
28#include "clang/Basic/Linkage.h"
29#include "clang/Basic/PartialDiagnostic.h"
30#include "clang/Basic/SourceLocation.h"
31#include "clang/Basic/Specifiers.h"
32#include "clang/Basic/Visibility.h"
33#include "llvm/ADT/APInt.h"
34#include "llvm/ADT/APSInt.h"
35#include "llvm/ADT/ArrayRef.h"
36#include "llvm/ADT/FoldingSet.h"
37#include "llvm/ADT/None.h"
38#include "llvm/ADT/Optional.h"
39#include "llvm/ADT/PointerIntPair.h"
40#include "llvm/ADT/PointerUnion.h"
41#include "llvm/ADT/StringRef.h"
42#include "llvm/ADT/Twine.h"
43#include "llvm/ADT/iterator_range.h"
44#include "llvm/Support/Casting.h"
45#include "llvm/Support/Compiler.h"
46#include "llvm/Support/ErrorHandling.h"
47#include "llvm/Support/PointerLikeTypeTraits.h"
48#include "llvm/Support/TrailingObjects.h"
49#include "llvm/Support/type_traits.h"
50#include <cassert>
51#include <cstddef>
52#include <cstdint>
53#include <cstring>
54#include <string>
55#include <type_traits>
56#include <utility>
57
58namespace clang {
59
60class ExtQuals;
61class QualType;
62class ConceptDecl;
63class TagDecl;
64class TemplateParameterList;
65class Type;
66
67enum {
68 TypeAlignmentInBits = 4,
69 TypeAlignment = 1 << TypeAlignmentInBits
70};
71
72namespace serialization {
73 template <class T> class AbstractTypeReader;
74 template <class T> class AbstractTypeWriter;
75}
76
77} // namespace clang
78
79namespace llvm {
80
81 template <typename T>
82 struct PointerLikeTypeTraits;
83 template<>
84 struct PointerLikeTypeTraits< ::clang::Type*> {
85 static inline void *getAsVoidPointer(::clang::Type *P) { return P; }
86
87 static inline ::clang::Type *getFromVoidPointer(void *P) {
88 return static_cast< ::clang::Type*>(P);
89 }
90
91 static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
92 };
93
94 template<>
95 struct PointerLikeTypeTraits< ::clang::ExtQuals*> {
96 static inline void *getAsVoidPointer(::clang::ExtQuals *P) { return P; }
97
98 static inline ::clang::ExtQuals *getFromVoidPointer(void *P) {
99 return static_cast< ::clang::ExtQuals*>(P);
100 }
101
102 static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
103 };
104
105} // namespace llvm
106
107namespace clang {
108
109class ASTContext;
110template <typename> class CanQual;
111class CXXRecordDecl;
112class DeclContext;
113class EnumDecl;
114class Expr;
115class ExtQualsTypeCommonBase;
116class FunctionDecl;
117class IdentifierInfo;
118class NamedDecl;
119class ObjCInterfaceDecl;
120class ObjCProtocolDecl;
121class ObjCTypeParamDecl;
122struct PrintingPolicy;
123class RecordDecl;
124class Stmt;
125class TagDecl;
126class TemplateArgument;
127class TemplateArgumentListInfo;
128class TemplateArgumentLoc;
129class TemplateTypeParmDecl;
130class TypedefNameDecl;
131class UnresolvedUsingTypenameDecl;
132
133using CanQualType = CanQual<Type>;
134
135// Provide forward declarations for all of the *Type classes.
136#define TYPE(Class, Base) class Class##Type;
137#include "clang/AST/TypeNodes.inc"
138
139/// The collection of all-type qualifiers we support.
140/// Clang supports five independent qualifiers:
141/// * C99: const, volatile, and restrict
142/// * MS: __unaligned
143/// * Embedded C (TR18037): address spaces
144/// * Objective C: the GC attributes (none, weak, or strong)
145class Qualifiers {
146public:
147 enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
148 Const = 0x1,
149 Restrict = 0x2,
150 Volatile = 0x4,
151 CVRMask = Const | Volatile | Restrict
152 };
153
154 enum GC {
155 GCNone = 0,
156 Weak,
157 Strong
158 };
159
160 enum ObjCLifetime {
161 /// There is no lifetime qualification on this type.
162 OCL_None,
163
164 /// This object can be modified without requiring retains or
165 /// releases.
166 OCL_ExplicitNone,
167
168 /// Assigning into this object requires the old value to be
169 /// released and the new value to be retained. The timing of the
170 /// release of the old value is inexact: it may be moved to
171 /// immediately after the last known point where the value is
172 /// live.
173 OCL_Strong,
174
175 /// Reading or writing from this object requires a barrier call.
176 OCL_Weak,
177
178 /// Assigning into this object requires a lifetime extension.
179 OCL_Autoreleasing
180 };
181
182 enum {
183 /// The maximum supported address space number.
184 /// 23 bits should be enough for anyone.
185 MaxAddressSpace = 0x7fffffu,
186
187 /// The width of the "fast" qualifier mask.
188 FastWidth = 3,
189
190 /// The fast qualifier mask.
191 FastMask = (1 << FastWidth) - 1
192 };
193
194 /// Returns the common set of qualifiers while removing them from
195 /// the given sets.
196 static Qualifiers removeCommonQualifiers(Qualifiers &L, Qualifiers &R) {
197 // If both are only CVR-qualified, bit operations are sufficient.
198 if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
199 Qualifiers Q;
200 Q.Mask = L.Mask & R.Mask;
201 L.Mask &= ~Q.Mask;
202 R.Mask &= ~Q.Mask;
203 return Q;
204 }
205
206 Qualifiers Q;
207 unsigned CommonCRV = L.getCVRQualifiers() & R.getCVRQualifiers();
208 Q.addCVRQualifiers(CommonCRV);
209 L.removeCVRQualifiers(CommonCRV);
210 R.removeCVRQualifiers(CommonCRV);
211
212 if (L.getObjCGCAttr() == R.getObjCGCAttr()) {
213 Q.setObjCGCAttr(L.getObjCGCAttr());
214 L.removeObjCGCAttr();
215 R.removeObjCGCAttr();
216 }
217
218 if (L.getObjCLifetime() == R.getObjCLifetime()) {
219 Q.setObjCLifetime(L.getObjCLifetime());
220 L.removeObjCLifetime();
221 R.removeObjCLifetime();
222 }
223
224 if (L.getAddressSpace() == R.getAddressSpace()) {
225 Q.setAddressSpace(L.getAddressSpace());
226 L.removeAddressSpace();
227 R.removeAddressSpace();
228 }
229 return Q;
230 }
231
232 static Qualifiers fromFastMask(unsigned Mask) {
233 Qualifiers Qs;
234 Qs.addFastQualifiers(Mask);
235 return Qs;
236 }
237
238 static Qualifiers fromCVRMask(unsigned CVR) {
239 Qualifiers Qs;
240 Qs.addCVRQualifiers(CVR);
241 return Qs;
242 }
243
244 static Qualifiers fromCVRUMask(unsigned CVRU) {
245 Qualifiers Qs;
246 Qs.addCVRUQualifiers(CVRU);
247 return Qs;
248 }
249
250 // Deserialize qualifiers from an opaque representation.
251 static Qualifiers fromOpaqueValue(unsigned opaque) {
252 Qualifiers Qs;
253 Qs.Mask = opaque;
254 return Qs;
255 }
256
257 // Serialize these qualifiers into an opaque representation.
258 unsigned getAsOpaqueValue() const {
259 return Mask;
260 }
261
262 bool hasConst() const { return Mask & Const; }
263 bool hasOnlyConst() const { return Mask == Const; }
264 void removeConst() { Mask &= ~Const; }
265 void addConst() { Mask |= Const; }
266
267 bool hasVolatile() const { return Mask & Volatile; }
268 bool hasOnlyVolatile() const { return Mask == Volatile; }
269 void removeVolatile() { Mask &= ~Volatile; }
270 void addVolatile() { Mask |= Volatile; }
271
272 bool hasRestrict() const { return Mask & Restrict; }
273 bool hasOnlyRestrict() const { return Mask == Restrict; }
274 void removeRestrict() { Mask &= ~Restrict; }
275 void addRestrict() { Mask |= Restrict; }
276
277 bool hasCVRQualifiers() const { return getCVRQualifiers(); }
278 unsigned getCVRQualifiers() const { return Mask & CVRMask; }
279 unsigned getCVRUQualifiers() const { return Mask & (CVRMask | UMask); }
280
281 void setCVRQualifiers(unsigned mask) {
282 assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((void)0);
283 Mask = (Mask & ~CVRMask) | mask;
284 }
285 void removeCVRQualifiers(unsigned mask) {
286 assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((void)0);
287 Mask &= ~mask;
288 }
289 void removeCVRQualifiers() {
290 removeCVRQualifiers(CVRMask);
291 }
292 void addCVRQualifiers(unsigned mask) {
293 assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((void)0);
294 Mask |= mask;
295 }
296 void addCVRUQualifiers(unsigned mask) {
297 assert(!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits")((void)0);
298 Mask |= mask;
299 }
300
301 bool hasUnaligned() const { return Mask & UMask; }
302 void setUnaligned(bool flag) {
303 Mask = (Mask & ~UMask) | (flag ? UMask : 0);
304 }
305 void removeUnaligned() { Mask &= ~UMask; }
306 void addUnaligned() { Mask |= UMask; }
307
308 bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
309 GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
310 void setObjCGCAttr(GC type) {
311 Mask = (Mask & ~GCAttrMask) | (type << GCAttrShift);
312 }
313 void removeObjCGCAttr() { setObjCGCAttr(GCNone); }
314 void addObjCGCAttr(GC type) {
315 assert(type)((void)0);
316 setObjCGCAttr(type);
317 }
318 Qualifiers withoutObjCGCAttr() const {
319 Qualifiers qs = *this;
320 qs.removeObjCGCAttr();
321 return qs;
322 }
323 Qualifiers withoutObjCLifetime() const {
324 Qualifiers qs = *this;
325 qs.removeObjCLifetime();
326 return qs;
327 }
328 Qualifiers withoutAddressSpace() const {
329 Qualifiers qs = *this;
330 qs.removeAddressSpace();
331 return qs;
332 }
333
334 bool hasObjCLifetime() const { return Mask & LifetimeMask; }
335 ObjCLifetime getObjCLifetime() const {
336 return ObjCLifetime((Mask & LifetimeMask) >> LifetimeShift);
337 }
338 void setObjCLifetime(ObjCLifetime type) {
339 Mask = (Mask & ~LifetimeMask) | (type << LifetimeShift);
340 }
341 void removeObjCLifetime() { setObjCLifetime(OCL_None); }
342 void addObjCLifetime(ObjCLifetime type) {
343 assert(type)((void)0);
344 assert(!hasObjCLifetime())((void)0);
345 Mask |= (type << LifetimeShift);
346 }
347
348 /// True if the lifetime is neither None or ExplicitNone.
349 bool hasNonTrivialObjCLifetime() const {
350 ObjCLifetime lifetime = getObjCLifetime();
351 return (lifetime > OCL_ExplicitNone);
352 }
353
354 /// True if the lifetime is either strong or weak.
355 bool hasStrongOrWeakObjCLifetime() const {
356 ObjCLifetime lifetime = getObjCLifetime();
357 return (lifetime == OCL_Strong || lifetime == OCL_Weak);
358 }
359
360 bool hasAddressSpace() const { return Mask & AddressSpaceMask; }
361 LangAS getAddressSpace() const {
362 return static_cast<LangAS>(Mask >> AddressSpaceShift);
363 }
364 bool hasTargetSpecificAddressSpace() const {
365 return isTargetAddressSpace(getAddressSpace());
366 }
367 /// Get the address space attribute value to be printed by diagnostics.
368 unsigned getAddressSpaceAttributePrintValue() const {
369 auto Addr = getAddressSpace();
370 // This function is not supposed to be used with language specific
371 // address spaces. If that happens, the diagnostic message should consider
372 // printing the QualType instead of the address space value.
373 assert(Addr == LangAS::Default || hasTargetSpecificAddressSpace())((void)0);
374 if (Addr != LangAS::Default)
375 return toTargetAddressSpace(Addr);
376 // TODO: The diagnostic messages where Addr may be 0 should be fixed
377 // since it cannot differentiate the situation where 0 denotes the default
378 // address space or user specified __attribute__((address_space(0))).
379 return 0;
380 }
381 void setAddressSpace(LangAS space) {
382 assert((unsigned)space <= MaxAddressSpace)((void)0);
383 Mask = (Mask & ~AddressSpaceMask)
384 | (((uint32_t) space) << AddressSpaceShift);
385 }
386 void removeAddressSpace() { setAddressSpace(LangAS::Default); }
387 void addAddressSpace(LangAS space) {
388 assert(space != LangAS::Default)((void)0);
389 setAddressSpace(space);
390 }
391
392 // Fast qualifiers are those that can be allocated directly
393 // on a QualType object.
394 bool hasFastQualifiers() const { return getFastQualifiers(); }
395 unsigned getFastQualifiers() const { return Mask & FastMask; }
396 void setFastQualifiers(unsigned mask) {
397 assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((void)0);
398 Mask = (Mask & ~FastMask) | mask;
399 }
400 void removeFastQualifiers(unsigned mask) {
401 assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((void)0);
402 Mask &= ~mask;
403 }
404 void removeFastQualifiers() {
405 removeFastQualifiers(FastMask);
406 }
407 void addFastQualifiers(unsigned mask) {
408 assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((void)0);
409 Mask |= mask;
410 }
411
412 /// Return true if the set contains any qualifiers which require an ExtQuals
413 /// node to be allocated.
414 bool hasNonFastQualifiers() const { return Mask & ~FastMask; }
415 Qualifiers getNonFastQualifiers() const {
416 Qualifiers Quals = *this;
417 Quals.setFastQualifiers(0);
418 return Quals;
419 }
420
421 /// Return true if the set contains any qualifiers.
422 bool hasQualifiers() const { return Mask; }
423 bool empty() const { return !Mask; }
424
425 /// Add the qualifiers from the given set to this set.
426 void addQualifiers(Qualifiers Q) {
427 // If the other set doesn't have any non-boolean qualifiers, just
428 // bit-or it in.
429 if (!(Q.Mask & ~CVRMask))
430 Mask |= Q.Mask;
431 else {
432 Mask |= (Q.Mask & CVRMask);
433 if (Q.hasAddressSpace())
434 addAddressSpace(Q.getAddressSpace());
435 if (Q.hasObjCGCAttr())
436 addObjCGCAttr(Q.getObjCGCAttr());
437 if (Q.hasObjCLifetime())
438 addObjCLifetime(Q.getObjCLifetime());
439 }
440 }
441
442 /// Remove the qualifiers from the given set from this set.
443 void removeQualifiers(Qualifiers Q) {
444 // If the other set doesn't have any non-boolean qualifiers, just
445 // bit-and the inverse in.
446 if (!(Q.Mask & ~CVRMask))
447 Mask &= ~Q.Mask;
448 else {
449 Mask &= ~(Q.Mask & CVRMask);
450 if (getObjCGCAttr() == Q.getObjCGCAttr())
451 removeObjCGCAttr();
452 if (getObjCLifetime() == Q.getObjCLifetime())
453 removeObjCLifetime();
454 if (getAddressSpace() == Q.getAddressSpace())
455 removeAddressSpace();
456 }
457 }
458
459 /// Add the qualifiers from the given set to this set, given that
460 /// they don't conflict.
461 void addConsistentQualifiers(Qualifiers qs) {
462 assert(getAddressSpace() == qs.getAddressSpace() ||((void)0)
463 !hasAddressSpace() || !qs.hasAddressSpace())((void)0);
464 assert(getObjCGCAttr() == qs.getObjCGCAttr() ||((void)0)
465 !hasObjCGCAttr() || !qs.hasObjCGCAttr())((void)0);
466 assert(getObjCLifetime() == qs.getObjCLifetime() ||((void)0)
467 !hasObjCLifetime() || !qs.hasObjCLifetime())((void)0);
468 Mask |= qs.Mask;
469 }
470
471 /// Returns true if address space A is equal to or a superset of B.
472 /// OpenCL v2.0 defines conversion rules (OpenCLC v2.0 s6.5.5) and notion of
473 /// overlapping address spaces.
474 /// CL1.1 or CL1.2:
475 /// every address space is a superset of itself.
476 /// CL2.0 adds:
477 /// __generic is a superset of any address space except for __constant.
478 static bool isAddressSpaceSupersetOf(LangAS A, LangAS B) {
479 // Address spaces must match exactly.
480 return A == B ||
481 // Otherwise in OpenCLC v2.0 s6.5.5: every address space except
482 // for __constant can be used as __generic.
483 (A == LangAS::opencl_generic && B != LangAS::opencl_constant) ||
484 // We also define global_device and global_host address spaces,
485 // to distinguish global pointers allocated on host from pointers
486 // allocated on device, which are a subset of __global.
487 (A == LangAS::opencl_global && (B == LangAS::opencl_global_device ||
488 B == LangAS::opencl_global_host)) ||
489 (A == LangAS::sycl_global && (B == LangAS::sycl_global_device ||
490 B == LangAS::sycl_global_host)) ||
491 // Consider pointer size address spaces to be equivalent to default.
492 ((isPtrSizeAddressSpace(A) || A == LangAS::Default) &&
493 (isPtrSizeAddressSpace(B) || B == LangAS::Default)) ||
494 // Default is a superset of SYCL address spaces.
495 (A == LangAS::Default &&
496 (B == LangAS::sycl_private || B == LangAS::sycl_local ||
497 B == LangAS::sycl_global || B == LangAS::sycl_global_device ||
498 B == LangAS::sycl_global_host));
499 }
500
501 /// Returns true if the address space in these qualifiers is equal to or
502 /// a superset of the address space in the argument qualifiers.
503 bool isAddressSpaceSupersetOf(Qualifiers other) const {
504 return isAddressSpaceSupersetOf(getAddressSpace(), other.getAddressSpace());
505 }
506
507 /// Determines if these qualifiers compatibly include another set.
508 /// Generally this answers the question of whether an object with the other
509 /// qualifiers can be safely used as an object with these qualifiers.
510 bool compatiblyIncludes(Qualifiers other) const {
511 return isAddressSpaceSupersetOf(other) &&
512 // ObjC GC qualifiers can match, be added, or be removed, but can't
513 // be changed.
514 (getObjCGCAttr() == other.getObjCGCAttr() || !hasObjCGCAttr() ||
515 !other.hasObjCGCAttr()) &&
516 // ObjC lifetime qualifiers must match exactly.
517 getObjCLifetime() == other.getObjCLifetime() &&
518 // CVR qualifiers may subset.
519 (((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
520 // U qualifier may superset.
521 (!other.hasUnaligned() || hasUnaligned());
522 }
523
524 /// Determines if these qualifiers compatibly include another set of
525 /// qualifiers from the narrow perspective of Objective-C ARC lifetime.
526 ///
527 /// One set of Objective-C lifetime qualifiers compatibly includes the other
528 /// if the lifetime qualifiers match, or if both are non-__weak and the
529 /// including set also contains the 'const' qualifier, or both are non-__weak
530 /// and one is None (which can only happen in non-ARC modes).
531 bool compatiblyIncludesObjCLifetime(Qualifiers other) const {
532 if (getObjCLifetime() == other.getObjCLifetime())
533 return true;
534
535 if (getObjCLifetime() == OCL_Weak || other.getObjCLifetime() == OCL_Weak)
536 return false;
537
538 if (getObjCLifetime() == OCL_None || other.getObjCLifetime() == OCL_None)
539 return true;
540
541 return hasConst();
542 }
543
544 /// Determine whether this set of qualifiers is a strict superset of
545 /// another set of qualifiers, not considering qualifier compatibility.
546 bool isStrictSupersetOf(Qualifiers Other) const;
547
548 bool operator==(Qualifiers Other) const { return Mask == Other.Mask; }
549 bool operator!=(Qualifiers Other) const { return Mask != Other.Mask; }
550
551 explicit operator bool() const { return hasQualifiers(); }
552
553 Qualifiers &operator+=(Qualifiers R) {
554 addQualifiers(R);
555 return *this;
556 }
557
558 // Union two qualifier sets. If an enumerated qualifier appears
559 // in both sets, use the one from the right.
560 friend Qualifiers operator+(Qualifiers L, Qualifiers R) {
561 L += R;
562 return L;
563 }
564
565 Qualifiers &operator-=(Qualifiers R) {
566 removeQualifiers(R);
567 return *this;
568 }
569
570 /// Compute the difference between two qualifier sets.
571 friend Qualifiers operator-(Qualifiers L, Qualifiers R) {
572 L -= R;
573 return L;
574 }
575
576 std::string getAsString() const;
577 std::string getAsString(const PrintingPolicy &Policy) const;
578
579 static std::string getAddrSpaceAsString(LangAS AS);
580
581 bool isEmptyWhenPrinted(const PrintingPolicy &Policy) const;
582 void print(raw_ostream &OS, const PrintingPolicy &Policy,
583 bool appendSpaceIfNonEmpty = false) const;
584
585 void Profile(llvm::FoldingSetNodeID &ID) const {
586 ID.AddInteger(Mask);
587 }
588
589private:
590 // bits: |0 1 2|3|4 .. 5|6 .. 8|9 ... 31|
591 // |C R V|U|GCAttr|Lifetime|AddressSpace|
592 uint32_t Mask = 0;
593
594 static const uint32_t UMask = 0x8;
595 static const uint32_t UShift = 3;
596 static const uint32_t GCAttrMask = 0x30;
597 static const uint32_t GCAttrShift = 4;
598 static const uint32_t LifetimeMask = 0x1C0;
599 static const uint32_t LifetimeShift = 6;
600 static const uint32_t AddressSpaceMask =
601 ~(CVRMask | UMask | GCAttrMask | LifetimeMask);
602 static const uint32_t AddressSpaceShift = 9;
603};
604
605/// A std::pair-like structure for storing a qualified type split
606/// into its local qualifiers and its locally-unqualified type.
607struct SplitQualType {
608 /// The locally-unqualified type.
609 const Type *Ty = nullptr;
610
611 /// The local qualifiers.
612 Qualifiers Quals;
613
614 SplitQualType() = default;
615 SplitQualType(const Type *ty, Qualifiers qs) : Ty(ty), Quals(qs) {}
616
617 SplitQualType getSingleStepDesugaredType() const; // end of this file
618
619 // Make std::tie work.
620 std::pair<const Type *,Qualifiers> asPair() const {
621 return std::pair<const Type *, Qualifiers>(Ty, Quals);
622 }
623
624 friend bool operator==(SplitQualType a, SplitQualType b) {
625 return a.Ty == b.Ty && a.Quals == b.Quals;
626 }
627 friend bool operator!=(SplitQualType a, SplitQualType b) {
628 return a.Ty != b.Ty || a.Quals != b.Quals;
629 }
630};
631
632/// The kind of type we are substituting Objective-C type arguments into.
633///
634/// The kind of substitution affects the replacement of type parameters when
635/// no concrete type information is provided, e.g., when dealing with an
636/// unspecialized type.
637enum class ObjCSubstitutionContext {
638 /// An ordinary type.
639 Ordinary,
640
641 /// The result type of a method or function.
642 Result,
643
644 /// The parameter type of a method or function.
645 Parameter,
646
647 /// The type of a property.
648 Property,
649
650 /// The superclass of a type.
651 Superclass,
652};
653
654/// A (possibly-)qualified type.
655///
656/// For efficiency, we don't store CV-qualified types as nodes on their
657/// own: instead each reference to a type stores the qualifiers. This
658/// greatly reduces the number of nodes we need to allocate for types (for
659/// example we only need one for 'int', 'const int', 'volatile int',
660/// 'const volatile int', etc).
661///
662/// As an added efficiency bonus, instead of making this a pair, we
663/// just store the two bits we care about in the low bits of the
664/// pointer. To handle the packing/unpacking, we make QualType be a
665/// simple wrapper class that acts like a smart pointer. A third bit
666/// indicates whether there are extended qualifiers present, in which
667/// case the pointer points to a special structure.
668class QualType {
669 friend class QualifierCollector;
670
671 // Thankfully, these are efficiently composable.
672 llvm::PointerIntPair<llvm::PointerUnion<const Type *, const ExtQuals *>,
673 Qualifiers::FastWidth> Value;
674
675 const ExtQuals *getExtQualsUnsafe() const {
676 return Value.getPointer().get<const ExtQuals*>();
677 }
678
679 const Type *getTypePtrUnsafe() const {
680 return Value.getPointer().get<const Type*>();
681 }
682
683 const ExtQualsTypeCommonBase *getCommonPtr() const {
684 assert(!isNull() && "Cannot retrieve a NULL type pointer")((void)0);
685 auto CommonPtrVal = reinterpret_cast<uintptr_t>(Value.getOpaqueValue());
686 CommonPtrVal &= ~(uintptr_t)((1 << TypeAlignmentInBits) - 1);
687 return reinterpret_cast<ExtQualsTypeCommonBase*>(CommonPtrVal);
688 }
689
690public:
691 QualType() = default;
692 QualType(const Type *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
693 QualType(const ExtQuals *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
694
695 unsigned getLocalFastQualifiers() const { return Value.getInt(); }
696 void setLocalFastQualifiers(unsigned Quals) { Value.setInt(Quals); }
697
698 /// Retrieves a pointer to the underlying (unqualified) type.
699 ///
700 /// This function requires that the type not be NULL. If the type might be
701 /// NULL, use the (slightly less efficient) \c getTypePtrOrNull().
702 const Type *getTypePtr() const;
703
704 const Type *getTypePtrOrNull() const;
705
706 /// Retrieves a pointer to the name of the base type.
707 const IdentifierInfo *getBaseTypeIdentifier() const;
708
709 /// Divides a QualType into its unqualified type and a set of local
710 /// qualifiers.
711 SplitQualType split() const;
712
713 void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }
714
715 static QualType getFromOpaquePtr(const void *Ptr) {
716 QualType T;
717 T.Value.setFromOpaqueValue(const_cast<void*>(Ptr));
718 return T;
719 }
720
721 const Type &operator*() const {
722 return *getTypePtr();
723 }
724
725 const Type *operator->() const {
726 return getTypePtr();
727 }
728
729 bool isCanonical() const;
730 bool isCanonicalAsParam() const;
731
732 /// Return true if this QualType doesn't point to a type yet.
733 bool isNull() const {
734 return Value.getPointer().isNull();
735 }
736
737 /// Determine whether this particular QualType instance has the
738 /// "const" qualifier set, without looking through typedefs that may have
739 /// added "const" at a different level.
740 bool isLocalConstQualified() const {
741 return (getLocalFastQualifiers() & Qualifiers::Const);
742 }
743
744 /// Determine whether this type is const-qualified.
745 bool isConstQualified() const;
746
747 /// Determine whether this particular QualType instance has the
748 /// "restrict" qualifier set, without looking through typedefs that may have
749 /// added "restrict" at a different level.
750 bool isLocalRestrictQualified() const {
751 return (getLocalFastQualifiers() & Qualifiers::Restrict);
752 }
753
754 /// Determine whether this type is restrict-qualified.
755 bool isRestrictQualified() const;
756
757 /// Determine whether this particular QualType instance has the
758 /// "volatile" qualifier set, without looking through typedefs that may have
759 /// added "volatile" at a different level.
760 bool isLocalVolatileQualified() const {
761 return (getLocalFastQualifiers() & Qualifiers::Volatile);
762 }
763
764 /// Determine whether this type is volatile-qualified.
765 bool isVolatileQualified() const;
766
767 /// Determine whether this particular QualType instance has any
768 /// qualifiers, without looking through any typedefs that might add
769 /// qualifiers at a different level.
770 bool hasLocalQualifiers() const {
771 return getLocalFastQualifiers() || hasLocalNonFastQualifiers();
772 }
773
774 /// Determine whether this type has any qualifiers.
775 bool hasQualifiers() const;
776
777 /// Determine whether this particular QualType instance has any
778 /// "non-fast" qualifiers, e.g., those that are stored in an ExtQualType
779 /// instance.
780 bool hasLocalNonFastQualifiers() const {
781 return Value.getPointer().is<const ExtQuals*>();
782 }
783
784 /// Retrieve the set of qualifiers local to this particular QualType
785 /// instance, not including any qualifiers acquired through typedefs or
786 /// other sugar.
787 Qualifiers getLocalQualifiers() const;
788
789 /// Retrieve the set of qualifiers applied to this type.
790 Qualifiers getQualifiers() const;
791
792 /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
793 /// local to this particular QualType instance, not including any qualifiers
794 /// acquired through typedefs or other sugar.
795 unsigned getLocalCVRQualifiers() const {
796 return getLocalFastQualifiers();
797 }
798
799 /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
800 /// applied to this type.
801 unsigned getCVRQualifiers() const;
802
803 bool isConstant(const ASTContext& Ctx) const {
804 return QualType::isConstant(*this, Ctx);
805 }
806
807 /// Determine whether this is a Plain Old Data (POD) type (C++ 3.9p10).
808 bool isPODType(const ASTContext &Context) const;
809
810 /// Return true if this is a POD type according to the rules of the C++98
811 /// standard, regardless of the current compilation's language.
812 bool isCXX98PODType(const ASTContext &Context) const;
813
814 /// Return true if this is a POD type according to the more relaxed rules
815 /// of the C++11 standard, regardless of the current compilation's language.
816 /// (C++0x [basic.types]p9). Note that, unlike
817 /// CXXRecordDecl::isCXX11StandardLayout, this takes DRs into account.
818 bool isCXX11PODType(const ASTContext &Context) const;
819
820 /// Return true if this is a trivial type per (C++0x [basic.types]p9)
821 bool isTrivialType(const ASTContext &Context) const;
822
823 /// Return true if this is a trivially copyable type (C++0x [basic.types]p9)
824 bool isTriviallyCopyableType(const ASTContext &Context) const;
825
826
827 /// Returns true if it is a class and it might be dynamic.
828 bool mayBeDynamicClass() const;
829
830 /// Returns true if it is not a class or if the class might not be dynamic.
831 bool mayBeNotDynamicClass() const;
832
833 // Don't promise in the API that anything besides 'const' can be
834 // easily added.
835
836 /// Add the `const` type qualifier to this QualType.
837 void addConst() {
838 addFastQualifiers(Qualifiers::Const);
839 }
840 QualType withConst() const {
841 return withFastQualifiers(Qualifiers::Const);
842 }
843
844 /// Add the `volatile` type qualifier to this QualType.
845 void addVolatile() {
846 addFastQualifiers(Qualifiers::Volatile);
847 }
848 QualType withVolatile() const {
849 return withFastQualifiers(Qualifiers::Volatile);
850 }
851
852 /// Add the `restrict` qualifier to this QualType.
853 void addRestrict() {
854 addFastQualifiers(Qualifiers::Restrict);
855 }
856 QualType withRestrict() const {
857 return withFastQualifiers(Qualifiers::Restrict);
858 }
859
860 QualType withCVRQualifiers(unsigned CVR) const {
861 return withFastQualifiers(CVR);
862 }
863
864 void addFastQualifiers(unsigned TQs) {
865 assert(!(TQs & ~Qualifiers::FastMask)((void)0)
866 && "non-fast qualifier bits set in mask!")((void)0);
867 Value.setInt(Value.getInt() | TQs);
868 }
869
870 void removeLocalConst();
871 void removeLocalVolatile();
872 void removeLocalRestrict();
873 void removeLocalCVRQualifiers(unsigned Mask);
874
875 void removeLocalFastQualifiers() { Value.setInt(0); }
876 void removeLocalFastQualifiers(unsigned Mask) {
877 assert(!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers")((void)0);
878 Value.setInt(Value.getInt() & ~Mask);
879 }
880
881 // Creates a type with the given qualifiers in addition to any
882 // qualifiers already on this type.
883 QualType withFastQualifiers(unsigned TQs) const {
884 QualType T = *this;
885 T.addFastQualifiers(TQs);
886 return T;
887 }
888
889 // Creates a type with exactly the given fast qualifiers, removing
890 // any existing fast qualifiers.
891 QualType withExactLocalFastQualifiers(unsigned TQs) const {
892 return withoutLocalFastQualifiers().withFastQualifiers(TQs);
893 }
894
895 // Removes fast qualifiers, but leaves any extended qualifiers in place.
896 QualType withoutLocalFastQualifiers() const {
897 QualType T = *this;
898 T.removeLocalFastQualifiers();
899 return T;
900 }
901
902 QualType getCanonicalType() const;
903
904 /// Return this type with all of the instance-specific qualifiers
905 /// removed, but without removing any qualifiers that may have been applied
906 /// through typedefs.
907 QualType getLocalUnqualifiedType() const { return QualType(getTypePtr(), 0); }
908
909 /// Retrieve the unqualified variant of the given type,
910 /// removing as little sugar as possible.
911 ///
912 /// This routine looks through various kinds of sugar to find the
913 /// least-desugared type that is unqualified. For example, given:
914 ///
915 /// \code
916 /// typedef int Integer;
917 /// typedef const Integer CInteger;
918 /// typedef CInteger DifferenceType;
919 /// \endcode
920 ///
921 /// Executing \c getUnqualifiedType() on the type \c DifferenceType will
922 /// desugar until we hit the type \c Integer, which has no qualifiers on it.
923 ///
924 /// The resulting type might still be qualified if it's sugar for an array
925 /// type. To strip qualifiers even from within a sugared array type, use
926 /// ASTContext::getUnqualifiedArrayType.
927 inline QualType getUnqualifiedType() const;
928
929 /// Retrieve the unqualified variant of the given type, removing as little
930 /// sugar as possible.
931 ///
932 /// Like getUnqualifiedType(), but also returns the set of
933 /// qualifiers that were built up.
934 ///
935 /// The resulting type might still be qualified if it's sugar for an array
936 /// type. To strip qualifiers even from within a sugared array type, use
937 /// ASTContext::getUnqualifiedArrayType.
938 inline SplitQualType getSplitUnqualifiedType() const;
939
940 /// Determine whether this type is more qualified than the other
941 /// given type, requiring exact equality for non-CVR qualifiers.
942 bool isMoreQualifiedThan(QualType Other) const;
943
944 /// Determine whether this type is at least as qualified as the other
945 /// given type, requiring exact equality for non-CVR qualifiers.
946 bool isAtLeastAsQualifiedAs(QualType Other) const;
947
948 QualType getNonReferenceType() const;
949
950 /// Determine the type of a (typically non-lvalue) expression with the
951 /// specified result type.
952 ///
953 /// This routine should be used for expressions for which the return type is
954 /// explicitly specified (e.g., in a cast or call) and isn't necessarily
955 /// an lvalue. It removes a top-level reference (since there are no
956 /// expressions of reference type) and deletes top-level cvr-qualifiers
957 /// from non-class types (in C++) or all types (in C).
958 QualType getNonLValueExprType(const ASTContext &Context) const;
959
960 /// Remove an outer pack expansion type (if any) from this type. Used as part
961 /// of converting the type of a declaration to the type of an expression that
962 /// references that expression. It's meaningless for an expression to have a
963 /// pack expansion type.
964 QualType getNonPackExpansionType() const;
965
966 /// Return the specified type with any "sugar" removed from
967 /// the type. This takes off typedefs, typeof's etc. If the outer level of
968 /// the type is already concrete, it returns it unmodified. This is similar
969 /// to getting the canonical type, but it doesn't remove *all* typedefs. For
970 /// example, it returns "T*" as "T*", (not as "int*"), because the pointer is
971 /// concrete.
972 ///
973 /// Qualifiers are left in place.
974 QualType getDesugaredType(const ASTContext &Context) const {
975 return getDesugaredType(*this, Context);
976 }
977
978 SplitQualType getSplitDesugaredType() const {
979 return getSplitDesugaredType(*this);
980 }
981
982 /// Return the specified type with one level of "sugar" removed from
983 /// the type.
984 ///
985 /// This routine takes off the first typedef, typeof, etc. If the outer level
986 /// of the type is already concrete, it returns it unmodified.
987 QualType getSingleStepDesugaredType(const ASTContext &Context) const {
988 return getSingleStepDesugaredTypeImpl(*this, Context);
989 }
990
991 /// Returns the specified type after dropping any
992 /// outer-level parentheses.
993 QualType IgnoreParens() const {
994 if (isa<ParenType>(*this))
995 return QualType::IgnoreParens(*this);
996 return *this;
997 }
998
999 /// Indicate whether the specified types and qualifiers are identical.
1000 friend bool operator==(const QualType &LHS, const QualType &RHS) {
1001 return LHS.Value == RHS.Value;
1002 }
1003 friend bool operator!=(const QualType &LHS, const QualType &RHS) {
1004 return LHS.Value != RHS.Value;
1005 }
1006 friend bool operator<(const QualType &LHS, const QualType &RHS) {
1007 return LHS.Value < RHS.Value;
1008 }
1009
1010 static std::string getAsString(SplitQualType split,
1011 const PrintingPolicy &Policy) {
1012 return getAsString(split.Ty, split.Quals, Policy);
1013 }
1014 static std::string getAsString(const Type *ty, Qualifiers qs,
1015 const PrintingPolicy &Policy);
1016
1017 std::string getAsString() const;
1018 std::string getAsString(const PrintingPolicy &Policy) const;
1019
1020 void print(raw_ostream &OS, const PrintingPolicy &Policy,
1021 const Twine &PlaceHolder = Twine(),
1022 unsigned Indentation = 0) const;
1023
1024 static void print(SplitQualType split, raw_ostream &OS,
1025 const PrintingPolicy &policy, const Twine &PlaceHolder,
1026 unsigned Indentation = 0) {
1027 return print(split.Ty, split.Quals, OS, policy, PlaceHolder, Indentation);
1028 }
1029
1030 static void print(const Type *ty, Qualifiers qs,
1031 raw_ostream &OS, const PrintingPolicy &policy,
1032 const Twine &PlaceHolder,
1033 unsigned Indentation = 0);
1034
1035 void getAsStringInternal(std::string &Str,
1036 const PrintingPolicy &Policy) const;
1037
1038 static void getAsStringInternal(SplitQualType split, std::string &out,
1039 const PrintingPolicy &policy) {
1040 return getAsStringInternal(split.Ty, split.Quals, out, policy);
1041 }
1042
1043 static void getAsStringInternal(const Type *ty, Qualifiers qs,
1044 std::string &out,
1045 const PrintingPolicy &policy);
1046
1047 class StreamedQualTypeHelper {
1048 const QualType &T;
1049 const PrintingPolicy &Policy;
1050 const Twine &PlaceHolder;
1051 unsigned Indentation;
1052
1053 public:
1054 StreamedQualTypeHelper(const QualType &T, const PrintingPolicy &Policy,
1055 const Twine &PlaceHolder, unsigned Indentation)
1056 : T(T), Policy(Policy), PlaceHolder(PlaceHolder),
1057 Indentation(Indentation) {}
1058
1059 friend raw_ostream &operator<<(raw_ostream &OS,
1060 const StreamedQualTypeHelper &SQT) {
1061 SQT.T.print(OS, SQT.Policy, SQT.PlaceHolder, SQT.Indentation);
1062 return OS;
1063 }
1064 };
1065
1066 StreamedQualTypeHelper stream(const PrintingPolicy &Policy,
1067 const Twine &PlaceHolder = Twine(),
1068 unsigned Indentation = 0) const {
1069 return StreamedQualTypeHelper(*this, Policy, PlaceHolder, Indentation);
1070 }
1071
1072 void dump(const char *s) const;
1073 void dump() const;
1074 void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
1075
1076 void Profile(llvm::FoldingSetNodeID &ID) const {
1077 ID.AddPointer(getAsOpaquePtr());
1078 }
1079
1080 /// Check if this type has any address space qualifier.
1081 inline bool hasAddressSpace() const;
1082
1083 /// Return the address space of this type.
1084 inline LangAS getAddressSpace() const;
1085
1086 /// Returns true if address space qualifiers overlap with T address space
1087 /// qualifiers.
1088 /// OpenCL C defines conversion rules for pointers to different address spaces
1089 /// and notion of overlapping address spaces.
1090 /// CL1.1 or CL1.2:
1091 /// address spaces overlap iff they are they same.
1092 /// OpenCL C v2.0 s6.5.5 adds:
1093 /// __generic overlaps with any address space except for __constant.
1094 bool isAddressSpaceOverlapping(QualType T) const {
1095 Qualifiers Q = getQualifiers();
1096 Qualifiers TQ = T.getQualifiers();
1097 // Address spaces overlap if at least one of them is a superset of another
1098 return Q.isAddressSpaceSupersetOf(TQ) || TQ.isAddressSpaceSupersetOf(Q);
1099 }
1100
1101 /// Returns gc attribute of this type.
1102 inline Qualifiers::GC getObjCGCAttr() const;
1103
1104 /// true when Type is objc's weak.
1105 bool isObjCGCWeak() const {
1106 return getObjCGCAttr() == Qualifiers::Weak;
1107 }
1108
1109 /// true when Type is objc's strong.
1110 bool isObjCGCStrong() const {
1111 return getObjCGCAttr() == Qualifiers::Strong;
1112 }
1113
1114 /// Returns lifetime attribute of this type.
1115 Qualifiers::ObjCLifetime getObjCLifetime() const {
1116 return getQualifiers().getObjCLifetime();
1117 }
1118
1119 bool hasNonTrivialObjCLifetime() const {
1120 return getQualifiers().hasNonTrivialObjCLifetime();
1121 }
1122
1123 bool hasStrongOrWeakObjCLifetime() const {
1124 return getQualifiers().hasStrongOrWeakObjCLifetime();
1125 }
1126
1127 // true when Type is objc's weak and weak is enabled but ARC isn't.
1128 bool isNonWeakInMRRWithObjCWeak(const ASTContext &Context) const;
1129
1130 enum PrimitiveDefaultInitializeKind {
1131 /// The type does not fall into any of the following categories. Note that
1132 /// this case is zero-valued so that values of this enum can be used as a
1133 /// boolean condition for non-triviality.
1134 PDIK_Trivial,
1135
1136 /// The type is an Objective-C retainable pointer type that is qualified
1137 /// with the ARC __strong qualifier.
1138 PDIK_ARCStrong,
1139
1140 /// The type is an Objective-C retainable pointer type that is qualified
1141 /// with the ARC __weak qualifier.
1142 PDIK_ARCWeak,
1143
1144 /// The type is a struct containing a field whose type is not PCK_Trivial.
1145 PDIK_Struct
1146 };
1147
1148 /// Functions to query basic properties of non-trivial C struct types.
1149
1150 /// Check if this is a non-trivial type that would cause a C struct
1151 /// transitively containing this type to be non-trivial to default initialize
1152 /// and return the kind.
1153 PrimitiveDefaultInitializeKind
1154 isNonTrivialToPrimitiveDefaultInitialize() const;
1155
1156 enum PrimitiveCopyKind {
1157 /// The type does not fall into any of the following categories. Note that
1158 /// this case is zero-valued so that values of this enum can be used as a
1159 /// boolean condition for non-triviality.
1160 PCK_Trivial,
1161
1162 /// The type would be trivial except that it is volatile-qualified. Types
1163 /// that fall into one of the other non-trivial cases may additionally be
1164 /// volatile-qualified.
1165 PCK_VolatileTrivial,
1166
1167 /// The type is an Objective-C retainable pointer type that is qualified
1168 /// with the ARC __strong qualifier.
1169 PCK_ARCStrong,
1170
1171 /// The type is an Objective-C retainable pointer type that is qualified
1172 /// with the ARC __weak qualifier.
1173 PCK_ARCWeak,
1174
1175 /// The type is a struct containing a field whose type is neither
1176 /// PCK_Trivial nor PCK_VolatileTrivial.
1177 /// Note that a C++ struct type does not necessarily match this; C++ copying
1178 /// semantics are too complex to express here, in part because they depend
1179 /// on the exact constructor or assignment operator that is chosen by
1180 /// overload resolution to do the copy.
1181 PCK_Struct
1182 };
1183
1184 /// Check if this is a non-trivial type that would cause a C struct
1185 /// transitively containing this type to be non-trivial to copy and return the
1186 /// kind.
1187 PrimitiveCopyKind isNonTrivialToPrimitiveCopy() const;
1188
1189 /// Check if this is a non-trivial type that would cause a C struct
1190 /// transitively containing this type to be non-trivial to destructively
1191 /// move and return the kind. Destructive move in this context is a C++-style
1192 /// move in which the source object is placed in a valid but unspecified state
1193 /// after it is moved, as opposed to a truly destructive move in which the
1194 /// source object is placed in an uninitialized state.
1195 PrimitiveCopyKind isNonTrivialToPrimitiveDestructiveMove() const;
1196
1197 enum DestructionKind {
1198 DK_none,
1199 DK_cxx_destructor,
1200 DK_objc_strong_lifetime,
1201 DK_objc_weak_lifetime,
1202 DK_nontrivial_c_struct
1203 };
1204
1205 /// Returns a nonzero value if objects of this type require
1206 /// non-trivial work to clean up after. Non-zero because it's
1207 /// conceivable that qualifiers (objc_gc(weak)?) could make
1208 /// something require destruction.
1209 DestructionKind isDestructedType() const {
1210 return isDestructedTypeImpl(*this);
1211 }
1212
1213 /// Check if this is or contains a C union that is non-trivial to
1214 /// default-initialize, which is a union that has a member that is non-trivial
1215 /// to default-initialize. If this returns true,
1216 /// isNonTrivialToPrimitiveDefaultInitialize returns PDIK_Struct.
1217 bool hasNonTrivialToPrimitiveDefaultInitializeCUnion() const;
1218
1219 /// Check if this is or contains a C union that is non-trivial to destruct,
1220 /// which is a union that has a member that is non-trivial to destruct. If
1221 /// this returns true, isDestructedType returns DK_nontrivial_c_struct.
1222 bool hasNonTrivialToPrimitiveDestructCUnion() const;
1223
1224 /// Check if this is or contains a C union that is non-trivial to copy, which
1225 /// is a union that has a member that is non-trivial to copy. If this returns
1226 /// true, isNonTrivialToPrimitiveCopy returns PCK_Struct.
1227 bool hasNonTrivialToPrimitiveCopyCUnion() const;
1228
1229 /// Determine whether expressions of the given type are forbidden
1230 /// from being lvalues in C.
1231 ///
1232 /// The expression types that are forbidden to be lvalues are:
1233 /// - 'void', but not qualified void
1234 /// - function types
1235 ///
1236 /// The exact rule here is C99 6.3.2.1:
1237 /// An lvalue is an expression with an object type or an incomplete
1238 /// type other than void.
1239 bool isCForbiddenLValueType() const;
1240
1241 /// Substitute type arguments for the Objective-C type parameters used in the
1242 /// subject type.
1243 ///
1244 /// \param ctx ASTContext in which the type exists.
1245 ///
1246 /// \param typeArgs The type arguments that will be substituted for the
1247 /// Objective-C type parameters in the subject type, which are generally
1248 /// computed via \c Type::getObjCSubstitutions. If empty, the type
1249 /// parameters will be replaced with their bounds or id/Class, as appropriate
1250 /// for the context.
1251 ///
1252 /// \param context The context in which the subject type was written.
1253 ///
1254 /// \returns the resulting type.
1255 QualType substObjCTypeArgs(ASTContext &ctx,
1256 ArrayRef<QualType> typeArgs,
1257 ObjCSubstitutionContext context) const;
1258
1259 /// Substitute type arguments from an object type for the Objective-C type
1260 /// parameters used in the subject type.
1261 ///
1262 /// This operation combines the computation of type arguments for
1263 /// substitution (\c Type::getObjCSubstitutions) with the actual process of
1264 /// substitution (\c QualType::substObjCTypeArgs) for the convenience of
1265 /// callers that need to perform a single substitution in isolation.
1266 ///
1267 /// \param objectType The type of the object whose member type we're
1268 /// substituting into. For example, this might be the receiver of a message
1269 /// or the base of a property access.
1270 ///
1271 /// \param dc The declaration context from which the subject type was
1272 /// retrieved, which indicates (for example) which type parameters should
1273 /// be substituted.
1274 ///
1275 /// \param context The context in which the subject type was written.
1276 ///
1277 /// \returns the subject type after replacing all of the Objective-C type
1278 /// parameters with their corresponding arguments.
1279 QualType substObjCMemberType(QualType objectType,
1280 const DeclContext *dc,
1281 ObjCSubstitutionContext context) const;
1282
1283 /// Strip Objective-C "__kindof" types from the given type.
1284 QualType stripObjCKindOfType(const ASTContext &ctx) const;
1285
1286 /// Remove all qualifiers including _Atomic.
1287 QualType getAtomicUnqualifiedType() const;
1288
1289private:
1290 // These methods are implemented in a separate translation unit;
1291 // "static"-ize them to avoid creating temporary QualTypes in the
1292 // caller.
1293 static bool isConstant(QualType T, const ASTContext& Ctx);
1294 static QualType getDesugaredType(QualType T, const ASTContext &Context);
1295 static SplitQualType getSplitDesugaredType(QualType T);
1296 static SplitQualType getSplitUnqualifiedTypeImpl(QualType type);
1297 static QualType getSingleStepDesugaredTypeImpl(QualType type,
1298 const ASTContext &C);
1299 static QualType IgnoreParens(QualType T);
1300 static DestructionKind isDestructedTypeImpl(QualType type);
1301
1302 /// Check if \param RD is or contains a non-trivial C union.
1303 static bool hasNonTrivialToPrimitiveDefaultInitializeCUnion(const RecordDecl *RD);
1304 static bool hasNonTrivialToPrimitiveDestructCUnion(const RecordDecl *RD);
1305 static bool hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD);
1306};
1307
1308} // namespace clang
1309
1310namespace llvm {
1311
1312/// Implement simplify_type for QualType, so that we can dyn_cast from QualType
1313/// to a specific Type class.
1314template<> struct simplify_type< ::clang::QualType> {
1315 using SimpleType = const ::clang::Type *;
1316
1317 static SimpleType getSimplifiedValue(::clang::QualType Val) {
1318 return Val.getTypePtr();
1319 }
1320};
1321
1322// Teach SmallPtrSet that QualType is "basically a pointer".
1323template<>
1324struct PointerLikeTypeTraits<clang::QualType> {
1325 static inline void *getAsVoidPointer(clang::QualType P) {
1326 return P.getAsOpaquePtr();
1327 }
1328
1329 static inline clang::QualType getFromVoidPointer(void *P) {
1330 return clang::QualType::getFromOpaquePtr(P);
1331 }
1332
1333 // Various qualifiers go in low bits.
1334 static constexpr int NumLowBitsAvailable = 0;
1335};
1336
1337} // namespace llvm
1338
1339namespace clang {
1340
1341/// Base class that is common to both the \c ExtQuals and \c Type
1342/// classes, which allows \c QualType to access the common fields between the
1343/// two.
1344class ExtQualsTypeCommonBase {
1345 friend class ExtQuals;
1346 friend class QualType;
1347 friend class Type;
1348
1349 /// The "base" type of an extended qualifiers type (\c ExtQuals) or
1350 /// a self-referential pointer (for \c Type).
1351 ///
1352 /// This pointer allows an efficient mapping from a QualType to its
1353 /// underlying type pointer.
1354 const Type *const BaseType;
1355
1356 /// The canonical type of this type. A QualType.
1357 QualType CanonicalType;
1358
1359 ExtQualsTypeCommonBase(const Type *baseType, QualType canon)
1360 : BaseType(baseType), CanonicalType(canon) {}
1361};
1362
1363/// We can encode up to four bits in the low bits of a
1364/// type pointer, but there are many more type qualifiers that we want
1365/// to be able to apply to an arbitrary type. Therefore we have this
1366/// struct, intended to be heap-allocated and used by QualType to
1367/// store qualifiers.
1368///
1369/// The current design tags the 'const', 'restrict', and 'volatile' qualifiers
1370/// in three low bits on the QualType pointer; a fourth bit records whether
1371/// the pointer is an ExtQuals node. The extended qualifiers (address spaces,
1372/// Objective-C GC attributes) are much more rare.
1373class ExtQuals : public ExtQualsTypeCommonBase, public llvm::FoldingSetNode {
1374 // NOTE: changing the fast qualifiers should be straightforward as
1375 // long as you don't make 'const' non-fast.
1376 // 1. Qualifiers:
1377 // a) Modify the bitmasks (Qualifiers::TQ and DeclSpec::TQ).
1378 // Fast qualifiers must occupy the low-order bits.
1379 // b) Update Qualifiers::FastWidth and FastMask.
1380 // 2. QualType:
1381 // a) Update is{Volatile,Restrict}Qualified(), defined inline.
1382 // b) Update remove{Volatile,Restrict}, defined near the end of
1383 // this header.
1384 // 3. ASTContext:
1385 // a) Update get{Volatile,Restrict}Type.
1386
1387 /// The immutable set of qualifiers applied by this node. Always contains
1388 /// extended qualifiers.
1389 Qualifiers Quals;
1390
1391 ExtQuals *this_() { return this; }
1392
1393public:
1394 ExtQuals(const Type *baseType, QualType canon, Qualifiers quals)
1395 : ExtQualsTypeCommonBase(baseType,
1396 canon.isNull() ? QualType(this_(), 0) : canon),
1397 Quals(quals) {
1398 assert(Quals.hasNonFastQualifiers()((void)0)
1399 && "ExtQuals created with no fast qualifiers")((void)0);
1400 assert(!Quals.hasFastQualifiers()((void)0)
1401 && "ExtQuals created with fast qualifiers")((void)0);
1402 }
1403
1404 Qualifiers getQualifiers() const { return Quals; }
1405
1406 bool hasObjCGCAttr() const { return Quals.hasObjCGCAttr(); }
1407 Qualifiers::GC getObjCGCAttr() const { return Quals.getObjCGCAttr(); }
1408
1409 bool hasObjCLifetime() const { return Quals.hasObjCLifetime(); }
1410 Qualifiers::ObjCLifetime getObjCLifetime() const {
1411 return Quals.getObjCLifetime();
1412 }
1413
1414 bool hasAddressSpace() const { return Quals.hasAddressSpace(); }
1415 LangAS getAddressSpace() const { return Quals.getAddressSpace(); }
1416
1417 const Type *getBaseType() const { return BaseType; }
1418
1419public:
1420 void Profile(llvm::FoldingSetNodeID &ID) const {
1421 Profile(ID, getBaseType(), Quals);
1422 }
1423
1424 static void Profile(llvm::FoldingSetNodeID &ID,
1425 const Type *BaseType,
1426 Qualifiers Quals) {
1427 assert(!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!")((void)0);
1428 ID.AddPointer(BaseType);
1429 Quals.Profile(ID);
1430 }
1431};
1432
1433/// The kind of C++11 ref-qualifier associated with a function type.
1434/// This determines whether a member function's "this" object can be an
1435/// lvalue, rvalue, or neither.
1436enum RefQualifierKind {
1437 /// No ref-qualifier was provided.
1438 RQ_None = 0,
1439
1440 /// An lvalue ref-qualifier was provided (\c &).
1441 RQ_LValue,
1442
1443 /// An rvalue ref-qualifier was provided (\c &&).
1444 RQ_RValue
1445};
1446
1447/// Which keyword(s) were used to create an AutoType.
1448enum class AutoTypeKeyword {
1449 /// auto
1450 Auto,
1451
1452 /// decltype(auto)
1453 DecltypeAuto,
1454
1455 /// __auto_type (GNU extension)
1456 GNUAutoType
1457};
1458
1459/// The base class of the type hierarchy.
1460///
1461/// A central concept with types is that each type always has a canonical
1462/// type. A canonical type is the type with any typedef names stripped out
1463/// of it or the types it references. For example, consider:
1464///
1465/// typedef int foo;
1466/// typedef foo* bar;
1467/// 'int *' 'foo *' 'bar'
1468///
1469/// There will be a Type object created for 'int'. Since int is canonical, its
1470/// CanonicalType pointer points to itself. There is also a Type for 'foo' (a
1471/// TypedefType). Its CanonicalType pointer points to the 'int' Type. Next
1472/// there is a PointerType that represents 'int*', which, like 'int', is
1473/// canonical. Finally, there is a PointerType type for 'foo*' whose canonical
1474/// type is 'int*', and there is a TypedefType for 'bar', whose canonical type
1475/// is also 'int*'.
1476///
1477/// Non-canonical types are useful for emitting diagnostics, without losing
1478/// information about typedefs being used. Canonical types are useful for type
1479/// comparisons (they allow by-pointer equality tests) and useful for reasoning
1480/// about whether something has a particular form (e.g. is a function type),
1481/// because they implicitly, recursively, strip all typedefs out of a type.
1482///
1483/// Types, once created, are immutable.
1484///
1485class alignas(8) Type : public ExtQualsTypeCommonBase {
1486public:
1487 enum TypeClass {
1488#define TYPE(Class, Base) Class,
1489#define LAST_TYPE(Class) TypeLast = Class
1490#define ABSTRACT_TYPE(Class, Base)
1491#include "clang/AST/TypeNodes.inc"
1492 };
1493
1494private:
1495 /// Bitfields required by the Type class.
1496 class TypeBitfields {
1497 friend class Type;
1498 template <class T> friend class TypePropertyCache;
1499
1500 /// TypeClass bitfield - Enum that specifies what subclass this belongs to.
1501 unsigned TC : 8;
1502
1503 /// Store information on the type dependency.
1504 unsigned Dependence : llvm::BitWidth<TypeDependence>;
1505
1506 /// True if the cache (i.e. the bitfields here starting with
1507 /// 'Cache') is valid.
1508 mutable unsigned CacheValid : 1;
1509
1510 /// Linkage of this type.
1511 mutable unsigned CachedLinkage : 3;
1512
1513 /// Whether this type involves and local or unnamed types.
1514 mutable unsigned CachedLocalOrUnnamed : 1;
1515
1516 /// Whether this type comes from an AST file.
1517 mutable unsigned FromAST : 1;
1518
1519 bool isCacheValid() const {
1520 return CacheValid;
1521 }
1522
1523 Linkage getLinkage() const {
1524 assert(isCacheValid() && "getting linkage from invalid cache")((void)0);
1525 return static_cast<Linkage>(CachedLinkage);
1526 }
1527
1528 bool hasLocalOrUnnamedType() const {
1529 assert(isCacheValid() && "getting linkage from invalid cache")((void)0);
1530 return CachedLocalOrUnnamed;
1531 }
1532 };
1533 enum { NumTypeBits = 8 + llvm::BitWidth<TypeDependence> + 6 };
1534
1535protected:
1536 // These classes allow subclasses to somewhat cleanly pack bitfields
1537 // into Type.
1538
1539 class ArrayTypeBitfields {
1540 friend class ArrayType;
1541
1542 unsigned : NumTypeBits;
1543
1544 /// CVR qualifiers from declarations like
1545 /// 'int X[static restrict 4]'. For function parameters only.
1546 unsigned IndexTypeQuals : 3;
1547
1548 /// Storage class qualifiers from declarations like
1549 /// 'int X[static restrict 4]'. For function parameters only.
1550 /// Actually an ArrayType::ArraySizeModifier.
1551 unsigned SizeModifier : 3;
1552 };
1553
1554 class ConstantArrayTypeBitfields {
1555 friend class ConstantArrayType;
1556
1557 unsigned : NumTypeBits + 3 + 3;
1558
1559 /// Whether we have a stored size expression.
1560 unsigned HasStoredSizeExpr : 1;
1561 };
1562
1563 class BuiltinTypeBitfields {
1564 friend class BuiltinType;
1565
1566 unsigned : NumTypeBits;
1567
1568 /// The kind (BuiltinType::Kind) of builtin type this is.
1569 unsigned Kind : 8;
1570 };
1571
1572 /// FunctionTypeBitfields store various bits belonging to FunctionProtoType.
1573 /// Only common bits are stored here. Additional uncommon bits are stored
1574 /// in a trailing object after FunctionProtoType.
1575 class FunctionTypeBitfields {
1576 friend class FunctionProtoType;
1577 friend class FunctionType;
1578
1579 unsigned : NumTypeBits;
1580
1581 /// Extra information which affects how the function is called, like
1582 /// regparm and the calling convention.
1583 unsigned ExtInfo : 13;
1584
1585 /// The ref-qualifier associated with a \c FunctionProtoType.
1586 ///
1587 /// This is a value of type \c RefQualifierKind.
1588 unsigned RefQualifier : 2;
1589
1590 /// Used only by FunctionProtoType, put here to pack with the
1591 /// other bitfields.
1592 /// The qualifiers are part of FunctionProtoType because...
1593 ///
1594 /// C++ 8.3.5p4: The return type, the parameter type list and the
1595 /// cv-qualifier-seq, [...], are part of the function type.
1596 unsigned FastTypeQuals : Qualifiers::FastWidth;
1597 /// Whether this function has extended Qualifiers.
1598 unsigned HasExtQuals : 1;
1599
1600 /// The number of parameters this function has, not counting '...'.
1601 /// According to [implimits] 8 bits should be enough here but this is
1602 /// somewhat easy to exceed with metaprogramming and so we would like to
1603 /// keep NumParams as wide as reasonably possible.
1604 unsigned NumParams : 16;
1605
1606 /// The type of exception specification this function has.
1607 unsigned ExceptionSpecType : 4;
1608
1609 /// Whether this function has extended parameter information.
1610 unsigned HasExtParameterInfos : 1;
1611
1612 /// Whether the function is variadic.
1613 unsigned Variadic : 1;
1614
1615 /// Whether this function has a trailing return type.
1616 unsigned HasTrailingReturn : 1;
1617 };
1618
1619 class ObjCObjectTypeBitfields {
1620 friend class ObjCObjectType;
1621
1622 unsigned : NumTypeBits;
1623
1624 /// The number of type arguments stored directly on this object type.
1625 unsigned NumTypeArgs : 7;
1626
1627 /// The number of protocols stored directly on this object type.
1628 unsigned NumProtocols : 6;
1629
1630 /// Whether this is a "kindof" type.
1631 unsigned IsKindOf : 1;
1632 };
1633
1634 class ReferenceTypeBitfields {
1635 friend class ReferenceType;
1636
1637 unsigned : NumTypeBits;
1638
1639 /// True if the type was originally spelled with an lvalue sigil.
1640 /// This is never true of rvalue references but can also be false
1641 /// on lvalue references because of C++0x [dcl.typedef]p9,
1642 /// as follows:
1643 ///
1644 /// typedef int &ref; // lvalue, spelled lvalue
1645 /// typedef int &&rvref; // rvalue
1646 /// ref &a; // lvalue, inner ref, spelled lvalue
1647 /// ref &&a; // lvalue, inner ref
1648 /// rvref &a; // lvalue, inner ref, spelled lvalue
1649 /// rvref &&a; // rvalue, inner ref
1650 unsigned SpelledAsLValue : 1;
1651
1652 /// True if the inner type is a reference type. This only happens
1653 /// in non-canonical forms.
1654 unsigned InnerRef : 1;
1655 };
1656
1657 class TypeWithKeywordBitfields {
1658 friend class TypeWithKeyword;
1659
1660 unsigned : NumTypeBits;
1661
1662 /// An ElaboratedTypeKeyword. 8 bits for efficient access.
1663 unsigned Keyword : 8;
1664 };
1665
1666 enum { NumTypeWithKeywordBits = 8 };
1667
1668 class ElaboratedTypeBitfields {
1669 friend class ElaboratedType;
1670
1671 unsigned : NumTypeBits;
1672 unsigned : NumTypeWithKeywordBits;
1673
1674 /// Whether the ElaboratedType has a trailing OwnedTagDecl.
1675 unsigned HasOwnedTagDecl : 1;
1676 };
1677
1678 class VectorTypeBitfields {
1679 friend class VectorType;
1680 friend class DependentVectorType;
1681
1682 unsigned : NumTypeBits;
1683
1684 /// The kind of vector, either a generic vector type or some
1685 /// target-specific vector type such as for AltiVec or Neon.
1686 unsigned VecKind : 3;
1687 /// The number of elements in the vector.
1688 uint32_t NumElements;
1689 };
1690
1691 class AttributedTypeBitfields {
1692 friend class AttributedType;
1693
1694 unsigned : NumTypeBits;
1695
1696 /// An AttributedType::Kind
1697 unsigned AttrKind : 32 - NumTypeBits;
1698 };
1699
1700 class AutoTypeBitfields {
1701 friend class AutoType;
1702
1703 unsigned : NumTypeBits;
1704
1705 /// Was this placeholder type spelled as 'auto', 'decltype(auto)',
1706 /// or '__auto_type'? AutoTypeKeyword value.
1707 unsigned Keyword : 2;
1708
1709 /// The number of template arguments in the type-constraints, which is
1710 /// expected to be able to hold at least 1024 according to [implimits].
1711 /// However as this limit is somewhat easy to hit with template
1712 /// metaprogramming we'd prefer to keep it as large as possible.
1713 /// At the moment it has been left as a non-bitfield since this type
1714 /// safely fits in 64 bits as an unsigned, so there is no reason to
1715 /// introduce the performance impact of a bitfield.
1716 unsigned NumArgs;
1717 };
1718
1719 class SubstTemplateTypeParmPackTypeBitfields {
1720 friend class SubstTemplateTypeParmPackType;
1721
1722 unsigned : NumTypeBits;
1723
1724 /// The number of template arguments in \c Arguments, which is
1725 /// expected to be able to hold at least 1024 according to [implimits].
1726 /// However as this limit is somewhat easy to hit with template
1727 /// metaprogramming we'd prefer to keep it as large as possible.
1728 /// At the moment it has been left as a non-bitfield since this type
1729 /// safely fits in 64 bits as an unsigned, so there is no reason to
1730 /// introduce the performance impact of a bitfield.
1731 unsigned NumArgs;
1732 };
1733
1734 class TemplateSpecializationTypeBitfields {
1735 friend class TemplateSpecializationType;
1736
1737 unsigned : NumTypeBits;
1738
1739 /// Whether this template specialization type is a substituted type alias.
1740 unsigned TypeAlias : 1;
1741
1742 /// The number of template arguments named in this class template
1743 /// specialization, which is expected to be able to hold at least 1024
1744 /// according to [implimits]. However, as this limit is somewhat easy to
1745 /// hit with template metaprogramming we'd prefer to keep it as large
1746 /// as possible. At the moment it has been left as a non-bitfield since
1747 /// this type safely fits in 64 bits as an unsigned, so there is no reason
1748 /// to introduce the performance impact of a bitfield.
1749 unsigned NumArgs;
1750 };
1751
1752 class DependentTemplateSpecializationTypeBitfields {
1753 friend class DependentTemplateSpecializationType;
1754
1755 unsigned : NumTypeBits;
1756 unsigned : NumTypeWithKeywordBits;
1757
1758 /// The number of template arguments named in this class template
1759 /// specialization, which is expected to be able to hold at least 1024
1760 /// according to [implimits]. However, as this limit is somewhat easy to
1761 /// hit with template metaprogramming we'd prefer to keep it as large
1762 /// as possible. At the moment it has been left as a non-bitfield since
1763 /// this type safely fits in 64 bits as an unsigned, so there is no reason
1764 /// to introduce the performance impact of a bitfield.
1765 unsigned NumArgs;
1766 };
1767
1768 class PackExpansionTypeBitfields {
1769 friend class PackExpansionType;
1770
1771 unsigned : NumTypeBits;
1772
1773 /// The number of expansions that this pack expansion will
1774 /// generate when substituted (+1), which is expected to be able to
1775 /// hold at least 1024 according to [implimits]. However, as this limit
1776 /// is somewhat easy to hit with template metaprogramming we'd prefer to
1777 /// keep it as large as possible. At the moment it has been left as a
1778 /// non-bitfield since this type safely fits in 64 bits as an unsigned, so
1779 /// there is no reason to introduce the performance impact of a bitfield.
1780 ///
1781 /// This field will only have a non-zero value when some of the parameter
1782 /// packs that occur within the pattern have been substituted but others
1783 /// have not.
1784 unsigned NumExpansions;
1785 };
1786
1787 union {
1788 TypeBitfields TypeBits;
1789 ArrayTypeBitfields ArrayTypeBits;
1790 ConstantArrayTypeBitfields ConstantArrayTypeBits;
1791 AttributedTypeBitfields AttributedTypeBits;
1792 AutoTypeBitfields AutoTypeBits;
1793 BuiltinTypeBitfields BuiltinTypeBits;
1794 FunctionTypeBitfields FunctionTypeBits;
1795 ObjCObjectTypeBitfields ObjCObjectTypeBits;
1796 ReferenceTypeBitfields ReferenceTypeBits;
1797 TypeWithKeywordBitfields TypeWithKeywordBits;
1798 ElaboratedTypeBitfields ElaboratedTypeBits;
1799 VectorTypeBitfields VectorTypeBits;
1800 SubstTemplateTypeParmPackTypeBitfields SubstTemplateTypeParmPackTypeBits;
1801 TemplateSpecializationTypeBitfields TemplateSpecializationTypeBits;
1802 DependentTemplateSpecializationTypeBitfields
1803 DependentTemplateSpecializationTypeBits;
1804 PackExpansionTypeBitfields PackExpansionTypeBits;
1805 };
1806
1807private:
1808 template <class T> friend class TypePropertyCache;
1809
1810 /// Set whether this type comes from an AST file.
1811 void setFromAST(bool V = true) const {
1812 TypeBits.FromAST = V;
1813 }
1814
1815protected:
1816 friend class ASTContext;
1817
1818 Type(TypeClass tc, QualType canon, TypeDependence Dependence)
1819 : ExtQualsTypeCommonBase(this,
1820 canon.isNull() ? QualType(this_(), 0) : canon) {
1821 static_assert(sizeof(*this) <= 8 + sizeof(ExtQualsTypeCommonBase),
1822 "changing bitfields changed sizeof(Type)!");
1823 static_assert(alignof(decltype(*this)) % sizeof(void *) == 0,
1824 "Insufficient alignment!");
1825 TypeBits.TC = tc;
1826 TypeBits.Dependence = static_cast<unsigned>(Dependence);
1827 TypeBits.CacheValid = false;
1828 TypeBits.CachedLocalOrUnnamed = false;
1829 TypeBits.CachedLinkage = NoLinkage;
1830 TypeBits.FromAST = false;
1831 }
1832
1833 // silence VC++ warning C4355: 'this' : used in base member initializer list
1834 Type *this_() { return this; }
1835
1836 void setDependence(TypeDependence D) {
1837 TypeBits.Dependence = static_cast<unsigned>(D);
1838 }
1839
1840 void addDependence(TypeDependence D) { setDependence(getDependence() | D); }
1841
1842public:
1843 friend class ASTReader;
1844 friend class ASTWriter;
1845 template <class T> friend class serialization::AbstractTypeReader;
1846 template <class T> friend class serialization::AbstractTypeWriter;
1847
1848 Type(const Type &) = delete;
1849 Type(Type &&) = delete;
1850 Type &operator=(const Type &) = delete;
1851 Type &operator=(Type &&) = delete;
1852
1853 TypeClass getTypeClass() const { return static_cast<TypeClass>(TypeBits.TC); }
1854
1855 /// Whether this type comes from an AST file.
1856 bool isFromAST() const { return TypeBits.FromAST; }
1857
1858 /// Whether this type is or contains an unexpanded parameter
1859 /// pack, used to support C++0x variadic templates.
1860 ///
1861 /// A type that contains a parameter pack shall be expanded by the
1862 /// ellipsis operator at some point. For example, the typedef in the
1863 /// following example contains an unexpanded parameter pack 'T':
1864 ///
1865 /// \code
1866 /// template<typename ...T>
1867 /// struct X {
1868 /// typedef T* pointer_types; // ill-formed; T is a parameter pack.
1869 /// };
1870 /// \endcode
1871 ///
1872 /// Note that this routine does not specify which
1873 bool containsUnexpandedParameterPack() const {
1874 return getDependence() & TypeDependence::UnexpandedPack;
1875 }
1876
1877 /// Determines if this type would be canonical if it had no further
1878 /// qualification.
1879 bool isCanonicalUnqualified() const {
1880 return CanonicalType == QualType(this, 0);
1881 }
1882
1883 /// Pull a single level of sugar off of this locally-unqualified type.
1884 /// Users should generally prefer SplitQualType::getSingleStepDesugaredType()
1885 /// or QualType::getSingleStepDesugaredType(const ASTContext&).
1886 QualType getLocallyUnqualifiedSingleStepDesugaredType() const;
1887
1888 /// As an extension, we classify types as one of "sized" or "sizeless";
1889 /// every type is one or the other. Standard types are all sized;
1890 /// sizeless types are purely an extension.
1891 ///
1892 /// Sizeless types contain data with no specified size, alignment,
1893 /// or layout.
1894 bool isSizelessType() const;
1895 bool isSizelessBuiltinType() const;
1896
1897 /// Determines if this is a sizeless type supported by the
1898 /// 'arm_sve_vector_bits' type attribute, which can be applied to a single
1899 /// SVE vector or predicate, excluding tuple types such as svint32x4_t.
1900 bool isVLSTBuiltinType() const;
1901
1902 /// Returns the representative type for the element of an SVE builtin type.
1903 /// This is used to represent fixed-length SVE vectors created with the
1904 /// 'arm_sve_vector_bits' type attribute as VectorType.
1905 QualType getSveEltType(const ASTContext &Ctx) const;
1906
1907 /// Types are partitioned into 3 broad categories (C99 6.2.5p1):
1908 /// object types, function types, and incomplete types.
1909
1910 /// Return true if this is an incomplete type.
1911 /// A type that can describe objects, but which lacks information needed to
1912 /// determine its size (e.g. void, or a fwd declared struct). Clients of this
1913 /// routine will need to determine if the size is actually required.
1914 ///
1915 /// Def If non-null, and the type refers to some kind of declaration
1916 /// that can be completed (such as a C struct, C++ class, or Objective-C
1917 /// class), will be set to the declaration.
1918 bool isIncompleteType(NamedDecl **Def = nullptr) const;
1919
1920 /// Return true if this is an incomplete or object
1921 /// type, in other words, not a function type.
1922 bool isIncompleteOrObjectType() const {
1923 return !isFunctionType();
1924 }
1925
1926 /// Determine whether this type is an object type.
1927 bool isObjectType() const {
1928 // C++ [basic.types]p8:
1929 // An object type is a (possibly cv-qualified) type that is not a
1930 // function type, not a reference type, and not a void type.
1931 return !isReferenceType() && !isFunctionType() && !isVoidType();
1932 }
1933
1934 /// Return true if this is a literal type
1935 /// (C++11 [basic.types]p10)
1936 bool isLiteralType(const ASTContext &Ctx) const;
1937
1938 /// Determine if this type is a structural type, per C++20 [temp.param]p7.
1939 bool isStructuralType() const;
1940
1941 /// Test if this type is a standard-layout type.
1942 /// (C++0x [basic.type]p9)
1943 bool isStandardLayoutType() const;
1944
1945 /// Helper methods to distinguish type categories. All type predicates
1946 /// operate on the canonical type, ignoring typedefs and qualifiers.
1947
1948 /// Returns true if the type is a builtin type.
1949 bool isBuiltinType() const;
1950
1951 /// Test for a particular builtin type.
1952 bool isSpecificBuiltinType(unsigned K) const;
1953
1954 /// Test for a type which does not represent an actual type-system type but
1955 /// is instead used as a placeholder for various convenient purposes within
1956 /// Clang. All such types are BuiltinTypes.
1957 bool isPlaceholderType() const;
1958 const BuiltinType *getAsPlaceholderType() const;
1959
1960 /// Test for a specific placeholder type.
1961 bool isSpecificPlaceholderType(unsigned K) const;
1962
1963 /// Test for a placeholder type other than Overload; see
1964 /// BuiltinType::isNonOverloadPlaceholderType.
1965 bool isNonOverloadPlaceholderType() const;
1966
1967 /// isIntegerType() does *not* include complex integers (a GCC extension).
1968 /// isComplexIntegerType() can be used to test for complex integers.
1969 bool isIntegerType() const; // C99 6.2.5p17 (int, char, bool, enum)
1970 bool isEnumeralType() const;
1971
1972 /// Determine whether this type is a scoped enumeration type.
1973 bool isScopedEnumeralType() const;
1974 bool isBooleanType() const;
1975 bool isCharType() const;
1976 bool isWideCharType() const;
1977 bool isChar8Type() const;
1978 bool isChar16Type() const;
1979 bool isChar32Type() const;
1980 bool isAnyCharacterType() const;
1981 bool isIntegralType(const ASTContext &Ctx) const;
1982
1983 /// Determine whether this type is an integral or enumeration type.
1984 bool isIntegralOrEnumerationType() const;
1985
1986 /// Determine whether this type is an integral or unscoped enumeration type.
1987 bool isIntegralOrUnscopedEnumerationType() const;
1988 bool isUnscopedEnumerationType() const;
1989
1990 /// Floating point categories.
1991 bool isRealFloatingType() const; // C99 6.2.5p10 (float, double, long double)
1992 /// isComplexType() does *not* include complex integers (a GCC extension).
1993 /// isComplexIntegerType() can be used to test for complex integers.
1994 bool isComplexType() const; // C99 6.2.5p11 (complex)
1995 bool isAnyComplexType() const; // C99 6.2.5p11 (complex) + Complex Int.
1996 bool isFloatingType() const; // C99 6.2.5p11 (real floating + complex)
1997 bool isHalfType() const; // OpenCL 6.1.1.1, NEON (IEEE 754-2008 half)
1998 bool isFloat16Type() const; // C11 extension ISO/IEC TS 18661
1999 bool isBFloat16Type() const;
2000 bool isFloat128Type() const;
2001 bool isRealType() const; // C99 6.2.5p17 (real floating + integer)
2002 bool isArithmeticType() const; // C99 6.2.5p18 (integer + floating)
2003 bool isVoidType() const; // C99 6.2.5p19
2004 bool isScalarType() const; // C99 6.2.5p21 (arithmetic + pointers)
2005 bool isAggregateType() const;
2006 bool isFundamentalType() const;
2007 bool isCompoundType() const;
2008
2009 // Type Predicates: Check to see if this type is structurally the specified
2010 // type, ignoring typedefs and qualifiers.
2011 bool isFunctionType() const;
2012 bool isFunctionNoProtoType() const { return getAs<FunctionNoProtoType>(); }
2013 bool isFunctionProtoType() const { return getAs<FunctionProtoType>(); }
2014 bool isPointerType() const;
2015 bool isAnyPointerType() const; // Any C pointer or ObjC object pointer
2016 bool isBlockPointerType() const;
2017 bool isVoidPointerType() const;
2018 bool isReferenceType() const;
2019 bool isLValueReferenceType() const;
2020 bool isRValueReferenceType() const;
2021 bool isObjectPointerType() const;
2022 bool isFunctionPointerType() const;
2023 bool isFunctionReferenceType() const;
2024 bool isMemberPointerType() const;
2025 bool isMemberFunctionPointerType() const;
2026 bool isMemberDataPointerType() const;
2027 bool isArrayType() const;
2028 bool isConstantArrayType() const;
2029 bool isIncompleteArrayType() const;
2030 bool isVariableArrayType() const;
2031 bool isDependentSizedArrayType() const;
2032 bool isRecordType() const;
2033 bool isClassType() const;
2034 bool isStructureType() const;
2035 bool isObjCBoxableRecordType() const;
2036 bool isInterfaceType() const;
2037 bool isStructureOrClassType() const;
2038 bool isUnionType() const;
2039 bool isComplexIntegerType() const; // GCC _Complex integer type.
2040 bool isVectorType() const; // GCC vector type.
2041 bool isExtVectorType() const; // Extended vector type.
2042 bool isMatrixType() const; // Matrix type.
2043 bool isConstantMatrixType() const; // Constant matrix type.
2044 bool isDependentAddressSpaceType() const; // value-dependent address space qualifier
2045 bool isObjCObjectPointerType() const; // pointer to ObjC object
2046 bool isObjCRetainableType() const; // ObjC object or block pointer
2047 bool isObjCLifetimeType() const; // (array of)* retainable type
2048 bool isObjCIndirectLifetimeType() const; // (pointer to)* lifetime type
2049 bool isObjCNSObjectType() const; // __attribute__((NSObject))
2050 bool isObjCIndependentClassType() const; // __attribute__((objc_independent_class))
2051 // FIXME: change this to 'raw' interface type, so we can used 'interface' type
2052 // for the common case.
2053 bool isObjCObjectType() const; // NSString or typeof(*(id)0)
2054 bool isObjCQualifiedInterfaceType() const; // NSString<foo>
2055 bool isObjCQualifiedIdType() const; // id<foo>
2056 bool isObjCQualifiedClassType() const; // Class<foo>
2057 bool isObjCObjectOrInterfaceType() const;
2058 bool isObjCIdType() const; // id
2059 bool isDecltypeType() const;
2060 /// Was this type written with the special inert-in-ARC __unsafe_unretained
2061 /// qualifier?
2062 ///
2063 /// This approximates the answer to the following question: if this
2064 /// translation unit were compiled in ARC, would this type be qualified
2065 /// with __unsafe_unretained?
2066 bool isObjCInertUnsafeUnretainedType() const {
2067 return hasAttr(attr::ObjCInertUnsafeUnretained);
2068 }
2069
2070 /// Whether the type is Objective-C 'id' or a __kindof type of an
2071 /// object type, e.g., __kindof NSView * or __kindof id
2072 /// <NSCopying>.
2073 ///
2074 /// \param bound Will be set to the bound on non-id subtype types,
2075 /// which will be (possibly specialized) Objective-C class type, or
2076 /// null for 'id.
2077 bool isObjCIdOrObjectKindOfType(const ASTContext &ctx,
2078 const ObjCObjectType *&bound) const;
2079
2080 bool isObjCClassType() const; // Class
2081
2082 /// Whether the type is Objective-C 'Class' or a __kindof type of an
2083 /// Class type, e.g., __kindof Class <NSCopying>.
2084 ///
2085 /// Unlike \c isObjCIdOrObjectKindOfType, there is no relevant bound
2086 /// here because Objective-C's type system cannot express "a class
2087 /// object for a subclass of NSFoo".
2088 bool isObjCClassOrClassKindOfType() const;
2089
2090 bool isBlockCompatibleObjCPointerType(ASTContext &ctx) const;
2091 bool isObjCSelType() const; // Class
2092 bool isObjCBuiltinType() const; // 'id' or 'Class'
2093 bool isObjCARCBridgableType() const;
2094 bool isCARCBridgableType() const;
2095 bool isTemplateTypeParmType() const; // C++ template type parameter
2096 bool isNullPtrType() const; // C++11 std::nullptr_t
2097 bool isNothrowT() const; // C++ std::nothrow_t
2098 bool isAlignValT() const; // C++17 std::align_val_t
2099 bool isStdByteType() const; // C++17 std::byte
2100 bool isAtomicType() const; // C11 _Atomic()
2101 bool isUndeducedAutoType() const; // C++11 auto or
2102 // C++14 decltype(auto)
2103 bool isTypedefNameType() const; // typedef or alias template
2104
2105#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
2106 bool is##Id##Type() const;
2107#include "clang/Basic/OpenCLImageTypes.def"
2108
2109 bool isImageType() const; // Any OpenCL image type
2110
2111 bool isSamplerT() const; // OpenCL sampler_t
2112 bool isEventT() const; // OpenCL event_t
2113 bool isClkEventT() const; // OpenCL clk_event_t
2114 bool isQueueT() const; // OpenCL queue_t
2115 bool isReserveIDT() const; // OpenCL reserve_id_t
2116
2117#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
2118 bool is##Id##Type() const;
2119#include "clang/Basic/OpenCLExtensionTypes.def"
2120 // Type defined in cl_intel_device_side_avc_motion_estimation OpenCL extension
2121 bool isOCLIntelSubgroupAVCType() const;
2122 bool isOCLExtOpaqueType() const; // Any OpenCL extension type
2123
2124 bool isPipeType() const; // OpenCL pipe type
2125 bool isExtIntType() const; // Extended Int Type
2126 bool isOpenCLSpecificType() const; // Any OpenCL specific type
2127
2128 /// Determines if this type, which must satisfy
2129 /// isObjCLifetimeType(), is implicitly __unsafe_unretained rather
2130 /// than implicitly __strong.
2131 bool isObjCARCImplicitlyUnretainedType() const;
2132
2133 /// Check if the type is the CUDA device builtin surface type.
2134 bool isCUDADeviceBuiltinSurfaceType() const;
2135 /// Check if the type is the CUDA device builtin texture type.
2136 bool isCUDADeviceBuiltinTextureType() const;
2137
2138 /// Return the implicit lifetime for this type, which must not be dependent.
2139 Qualifiers::ObjCLifetime getObjCARCImplicitLifetime() const;
2140
2141 enum ScalarTypeKind {
2142 STK_CPointer,
2143 STK_BlockPointer,
2144 STK_ObjCObjectPointer,
2145 STK_MemberPointer,
2146 STK_Bool,
2147 STK_Integral,
2148 STK_Floating,
2149 STK_IntegralComplex,
2150 STK_FloatingComplex,
2151 STK_FixedPoint
2152 };
2153
2154 /// Given that this is a scalar type, classify it.
2155 ScalarTypeKind getScalarTypeKind() const;
2156
2157 TypeDependence getDependence() const {
2158 return static_cast<TypeDependence>(TypeBits.Dependence);
2159 }
2160
2161 /// Whether this type is an error type.
2162 bool containsErrors() const {
2163 return getDependence() & TypeDependence::Error;
2164 }
2165
2166 /// Whether this type is a dependent type, meaning that its definition
2167 /// somehow depends on a template parameter (C++ [temp.dep.type]).
2168 bool isDependentType() const {
2169 return getDependence() & TypeDependence::Dependent;
2170 }
2171
2172 /// Determine whether this type is an instantiation-dependent type,
2173 /// meaning that the type involves a template parameter (even if the
2174 /// definition does not actually depend on the type substituted for that
2175 /// template parameter).
2176 bool isInstantiationDependentType() const {
2177 return getDependence() & TypeDependence::Instantiation;
2178 }
2179
2180 /// Determine whether this type is an undeduced type, meaning that
2181 /// it somehow involves a C++11 'auto' type or similar which has not yet been
2182 /// deduced.
2183 bool isUndeducedType() const;
2184
2185 /// Whether this type is a variably-modified type (C99 6.7.5).
2186 bool isVariablyModifiedType() const {
2187 return getDependence() & TypeDependence::VariablyModified;
2188 }
2189
2190 /// Whether this type involves a variable-length array type
2191 /// with a definite size.
2192 bool hasSizedVLAType() const;
2193
2194 /// Whether this type is or contains a local or unnamed type.
2195 bool hasUnnamedOrLocalType() const;
2196
2197 bool isOverloadableType() const;
2198
2199 /// Determine wither this type is a C++ elaborated-type-specifier.
2200 bool isElaboratedTypeSpecifier() const;
2201
2202 bool canDecayToPointerType() const;
2203
2204 /// Whether this type is represented natively as a pointer. This includes
2205 /// pointers, references, block pointers, and Objective-C interface,
2206 /// qualified id, and qualified interface types, as well as nullptr_t.
2207 bool hasPointerRepresentation() const;
2208
2209 /// Whether this type can represent an objective pointer type for the
2210 /// purpose of GC'ability
2211 bool hasObjCPointerRepresentation() const;
2212
2213 /// Determine whether this type has an integer representation
2214 /// of some sort, e.g., it is an integer type or a vector.
2215 bool hasIntegerRepresentation() const;
2216
2217 /// Determine whether this type has an signed integer representation
2218 /// of some sort, e.g., it is an signed integer type or a vector.
2219 bool hasSignedIntegerRepresentation() const;
2220
2221 /// Determine whether this type has an unsigned integer representation
2222 /// of some sort, e.g., it is an unsigned integer type or a vector.
2223 bool hasUnsignedIntegerRepresentation() const;
2224
2225 /// Determine whether this type has a floating-point representation
2226 /// of some sort, e.g., it is a floating-point type or a vector thereof.
2227 bool hasFloatingRepresentation() const;
2228
2229 // Type Checking Functions: Check to see if this type is structurally the
2230 // specified type, ignoring typedefs and qualifiers, and return a pointer to
2231 // the best type we can.
2232 const RecordType *getAsStructureType() const;
2233 /// NOTE: getAs*ArrayType are methods on ASTContext.
2234 const RecordType *getAsUnionType() const;
2235 const ComplexType *getAsComplexIntegerType() const; // GCC complex int type.
2236 const ObjCObjectType *getAsObjCInterfaceType() const;
2237
2238 // The following is a convenience method that returns an ObjCObjectPointerType
2239 // for object declared using an interface.
2240 const ObjCObjectPointerType *getAsObjCInterfacePointerType() const;
2241 const ObjCObjectPointerType *getAsObjCQualifiedIdType() const;
2242 const ObjCObjectPointerType *getAsObjCQualifiedClassType() const;
2243 const ObjCObjectType *getAsObjCQualifiedInterfaceType() const;
2244
2245 /// Retrieves the CXXRecordDecl that this type refers to, either
2246 /// because the type is a RecordType or because it is the injected-class-name
2247 /// type of a class template or class template partial specialization.
2248 CXXRecordDecl *getAsCXXRecordDecl() const;
2249
2250 /// Retrieves the RecordDecl this type refers to.
2251 RecordDecl *getAsRecordDecl() const;
2252
2253 /// Retrieves the TagDecl that this type refers to, either
2254 /// because the type is a TagType or because it is the injected-class-name
2255 /// type of a class template or class template partial specialization.
2256 TagDecl *getAsTagDecl() const;
2257
2258 /// If this is a pointer or reference to a RecordType, return the
2259 /// CXXRecordDecl that the type refers to.
2260 ///
2261 /// If this is not a pointer or reference, or the type being pointed to does
2262 /// not refer to a CXXRecordDecl, returns NULL.
2263 const CXXRecordDecl *getPointeeCXXRecordDecl() const;
2264
2265 /// Get the DeducedType whose type will be deduced for a variable with
2266 /// an initializer of this type. This looks through declarators like pointer
2267 /// types, but not through decltype or typedefs.
2268 DeducedType *getContainedDeducedType() const;
2269
2270 /// Get the AutoType whose type will be deduced for a variable with
2271 /// an initializer of this type. This looks through declarators like pointer
2272 /// types, but not through decltype or typedefs.
2273 AutoType *getContainedAutoType() const {
2274 return dyn_cast_or_null<AutoType>(getContainedDeducedType());
2275 }
2276
2277 /// Determine whether this type was written with a leading 'auto'
2278 /// corresponding to a trailing return type (possibly for a nested
2279 /// function type within a pointer to function type or similar).
2280 bool hasAutoForTrailingReturnType() const;
2281
2282 /// Member-template getAs<specific type>'. Look through sugar for
2283 /// an instance of \<specific type>. This scheme will eventually
2284 /// replace the specific getAsXXXX methods above.
2285 ///
2286 /// There are some specializations of this member template listed
2287 /// immediately following this class.
2288 template <typename T> const T *getAs() const;
2289
2290 /// Member-template getAsAdjusted<specific type>. Look through specific kinds
2291 /// of sugar (parens, attributes, etc) for an instance of \<specific type>.
2292 /// This is used when you need to walk over sugar nodes that represent some
2293 /// kind of type adjustment from a type that was written as a \<specific type>
2294 /// to another type that is still canonically a \<specific type>.
2295 template <typename T> const T *getAsAdjusted() const;
2296
2297 /// A variant of getAs<> for array types which silently discards
2298 /// qualifiers from the outermost type.
2299 const ArrayType *getAsArrayTypeUnsafe() const;
2300
2301 /// Member-template castAs<specific type>. Look through sugar for
2302 /// the underlying instance of \<specific type>.
2303 ///
2304 /// This method has the same relationship to getAs<T> as cast<T> has
2305 /// to dyn_cast<T>; which is to say, the underlying type *must*
2306 /// have the intended type, and this method will never return null.
2307 template <typename T> const T *castAs() const;
2308
2309 /// A variant of castAs<> for array type which silently discards
2310 /// qualifiers from the outermost type.
2311 const ArrayType *castAsArrayTypeUnsafe() const;
2312
2313 /// Determine whether this type had the specified attribute applied to it
2314 /// (looking through top-level type sugar).
2315 bool hasAttr(attr::Kind AK) const;
2316
2317 /// Get the base element type of this type, potentially discarding type
2318 /// qualifiers. This should never be used when type qualifiers
2319 /// are meaningful.
2320 const Type *getBaseElementTypeUnsafe() const;
2321
2322 /// If this is an array type, return the element type of the array,
2323 /// potentially with type qualifiers missing.
2324 /// This should never be used when type qualifiers are meaningful.
2325 const Type *getArrayElementTypeNoTypeQual() const;
2326
2327 /// If this is a pointer type, return the pointee type.
2328 /// If this is an array type, return the array element type.
2329 /// This should never be used when type qualifiers are meaningful.
2330 const Type *getPointeeOrArrayElementType() const;
2331
2332 /// If this is a pointer, ObjC object pointer, or block
2333 /// pointer, this returns the respective pointee.
2334 QualType getPointeeType() const;
2335
2336 /// Return the specified type with any "sugar" removed from the type,
2337 /// removing any typedefs, typeofs, etc., as well as any qualifiers.
2338 const Type *getUnqualifiedDesugaredType() const;
2339
2340 /// More type predicates useful for type checking/promotion
2341 bool isPromotableIntegerType() const; // C99 6.3.1.1p2
2342
2343 /// Return true if this is an integer type that is
2344 /// signed, according to C99 6.2.5p4 [char, signed char, short, int, long..],
2345 /// or an enum decl which has a signed representation.
2346 bool isSignedIntegerType() const;
2347
2348 /// Return true if this is an integer type that is
2349 /// unsigned, according to C99 6.2.5p6 [which returns true for _Bool],
2350 /// or an enum decl which has an unsigned representation.
2351 bool isUnsignedIntegerType() const;
2352
2353 /// Determines whether this is an integer type that is signed or an
2354 /// enumeration types whose underlying type is a signed integer type.
2355 bool isSignedIntegerOrEnumerationType() const;
2356
2357 /// Determines whether this is an integer type that is unsigned or an
2358 /// enumeration types whose underlying type is a unsigned integer type.
2359 bool isUnsignedIntegerOrEnumerationType() const;
2360
2361 /// Return true if this is a fixed point type according to
2362 /// ISO/IEC JTC1 SC22 WG14 N1169.
2363 bool isFixedPointType() const;
2364
2365 /// Return true if this is a fixed point or integer type.
2366 bool isFixedPointOrIntegerType() const;
2367
2368 /// Return true if this is a saturated fixed point type according to
2369 /// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2370 bool isSaturatedFixedPointType() const;
2371
2372 /// Return true if this is a saturated fixed point type according to
2373 /// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
2374 bool isUnsaturatedFixedPointType() const;
2375
2376 /// Return true if this is a fixed point type that is signed according
2377 /// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2378 bool isSignedFixedPointType() const;
2379
2380 /// Return true if this is a fixed point type that is unsigned according
2381 /// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
2382 bool isUnsignedFixedPointType() const;
2383
2384 /// Return true if this is not a variable sized type,
2385 /// according to the rules of C99 6.7.5p3. It is not legal to call this on
2386 /// incomplete types.
2387 bool isConstantSizeType() const;
2388
2389 /// Returns true if this type can be represented by some
2390 /// set of type specifiers.
2391 bool isSpecifierType() const;
2392
2393 /// Determine the linkage of this type.
2394 Linkage getLinkage() const;
2395
2396 /// Determine the visibility of this type.
2397 Visibility getVisibility() const {
2398 return getLinkageAndVisibility().getVisibility();
2399 }
2400
2401 /// Return true if the visibility was explicitly set is the code.
2402 bool isVisibilityExplicit() const {
2403 return getLinkageAndVisibility().isVisibilityExplicit();
2404 }
2405
2406 /// Determine the linkage and visibility of this type.
2407 LinkageInfo getLinkageAndVisibility() const;
2408
2409 /// True if the computed linkage is valid. Used for consistency
2410 /// checking. Should always return true.
2411 bool isLinkageValid() const;
2412
2413 /// Determine the nullability of the given type.
2414 ///
2415 /// Note that nullability is only captured as sugar within the type
2416 /// system, not as part of the canonical type, so nullability will
2417 /// be lost by canonicalization and desugaring.
2418 Optional<NullabilityKind> getNullability(const ASTContext &context) const;
2419
2420 /// Determine whether the given type can have a nullability
2421 /// specifier applied to it, i.e., if it is any kind of pointer type.
2422 ///
2423 /// \param ResultIfUnknown The value to return if we don't yet know whether
2424 /// this type can have nullability because it is dependent.
2425 bool canHaveNullability(bool ResultIfUnknown = true) const;
2426
2427 /// Retrieve the set of substitutions required when accessing a member
2428 /// of the Objective-C receiver type that is declared in the given context.
2429 ///
2430 /// \c *this is the type of the object we're operating on, e.g., the
2431 /// receiver for a message send or the base of a property access, and is
2432 /// expected to be of some object or object pointer type.
2433 ///
2434 /// \param dc The declaration context for which we are building up a
2435 /// substitution mapping, which should be an Objective-C class, extension,
2436 /// category, or method within.
2437 ///
2438 /// \returns an array of type arguments that can be substituted for
2439 /// the type parameters of the given declaration context in any type described
2440 /// within that context, or an empty optional to indicate that no
2441 /// substitution is required.
2442 Optional<ArrayRef<QualType>>
2443 getObjCSubstitutions(const DeclContext *dc) const;
2444
2445 /// Determines if this is an ObjC interface type that may accept type
2446 /// parameters.
2447 bool acceptsObjCTypeParams() const;
2448
2449 const char *getTypeClassName() const;
2450
2451 QualType getCanonicalTypeInternal() const {
2452 return CanonicalType;
2453 }
2454
2455 CanQualType getCanonicalTypeUnqualified() const; // in CanonicalType.h
2456 void dump() const;
2457 void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
2458};
2459
2460/// This will check for a TypedefType by removing any existing sugar
2461/// until it reaches a TypedefType or a non-sugared type.
2462template <> const TypedefType *Type::getAs() const;
2463
2464/// This will check for a TemplateSpecializationType by removing any
2465/// existing sugar until it reaches a TemplateSpecializationType or a
2466/// non-sugared type.
2467template <> const TemplateSpecializationType *Type::getAs() const;
2468
2469/// This will check for an AttributedType by removing any existing sugar
2470/// until it reaches an AttributedType or a non-sugared type.
2471template <> const AttributedType *Type::getAs() const;
2472
2473// We can do canonical leaf types faster, because we don't have to
2474// worry about preserving child type decoration.
2475#define TYPE(Class, Base)
2476#define LEAF_TYPE(Class) \
2477template <> inline const Class##Type *Type::getAs() const { \
2478 return dyn_cast<Class##Type>(CanonicalType); \
2479} \
2480template <> inline const Class##Type *Type::castAs() const { \
2481 return cast<Class##Type>(CanonicalType); \
2482}
2483#include "clang/AST/TypeNodes.inc"
2484
2485/// This class is used for builtin types like 'int'. Builtin
2486/// types are always canonical and have a literal name field.
2487class BuiltinType : public Type {
2488public:
2489 enum Kind {
2490// OpenCL image types
2491#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) Id,
2492#include "clang/Basic/OpenCLImageTypes.def"
2493// OpenCL extension types
2494#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) Id,
2495#include "clang/Basic/OpenCLExtensionTypes.def"
2496// SVE Types
2497#define SVE_TYPE(Name, Id, SingletonId) Id,
2498#include "clang/Basic/AArch64SVEACLETypes.def"
2499// PPC MMA Types
2500#define PPC_VECTOR_TYPE(Name, Id, Size) Id,
2501#include "clang/Basic/PPCTypes.def"
2502// RVV Types
2503#define RVV_TYPE(Name, Id, SingletonId) Id,
2504#include "clang/Basic/RISCVVTypes.def"
2505// All other builtin types
2506#define BUILTIN_TYPE(Id, SingletonId) Id,
2507#define LAST_BUILTIN_TYPE(Id) LastKind = Id
2508#include "clang/AST/BuiltinTypes.def"
2509 };
2510
2511private:
2512 friend class ASTContext; // ASTContext creates these.
2513
2514 BuiltinType(Kind K)
2515 : Type(Builtin, QualType(),
2516 K == Dependent ? TypeDependence::DependentInstantiation
2517 : TypeDependence::None) {
2518 BuiltinTypeBits.Kind = K;
2519 }
2520
2521public:
2522 Kind getKind() const { return static_cast<Kind>(BuiltinTypeBits.Kind); }
2523 StringRef getName(const PrintingPolicy &Policy) const;
2524
2525 const char *getNameAsCString(const PrintingPolicy &Policy) const {
2526 // The StringRef is null-terminated.
2527 StringRef str = getName(Policy);
2528 assert(!str.empty() && str.data()[str.size()] == '\0')((void)0);
2529 return str.data();
2530 }
2531
2532 bool isSugared() const { return false; }
2533 QualType desugar() const { return QualType(this, 0); }
2534
2535 bool isInteger() const {
2536 return getKind() >= Bool && getKind() <= Int128;
2537 }
2538
2539 bool isSignedInteger() const {
2540 return getKind() >= Char_S && getKind() <= Int128;
2541 }
2542
2543 bool isUnsignedInteger() const {
2544 return getKind() >= Bool && getKind() <= UInt128;
2545 }
2546
2547 bool isFloatingPoint() const {
2548 return getKind() >= Half && getKind() <= Float128;
2549 }
2550
2551 /// Determines whether the given kind corresponds to a placeholder type.
2552 static bool isPlaceholderTypeKind(Kind K) {
2553 return K >= Overload;
2554 }
2555
2556 /// Determines whether this type is a placeholder type, i.e. a type
2557 /// which cannot appear in arbitrary positions in a fully-formed
2558 /// expression.
2559 bool isPlaceholderType() const {
2560 return isPlaceholderTypeKind(getKind());
2561 }
2562
2563 /// Determines whether this type is a placeholder type other than
2564 /// Overload. Most placeholder types require only syntactic
2565 /// information about their context in order to be resolved (e.g.
2566 /// whether it is a call expression), which means they can (and
2567 /// should) be resolved in an earlier "phase" of analysis.
2568 /// Overload expressions sometimes pick up further information
2569 /// from their context, like whether the context expects a
2570 /// specific function-pointer type, and so frequently need
2571 /// special treatment.
2572 bool isNonOverloadPlaceholderType() const {
2573 return getKind() > Overload;
2574 }
2575
2576 static bool classof(const Type *T) { return T->getTypeClass() == Builtin; }
2577};
2578
2579/// Complex values, per C99 6.2.5p11. This supports the C99 complex
2580/// types (_Complex float etc) as well as the GCC integer complex extensions.
2581class ComplexType : public Type, public llvm::FoldingSetNode {
2582 friend class ASTContext; // ASTContext creates these.
2583
2584 QualType ElementType;
2585
2586 ComplexType(QualType Element, QualType CanonicalPtr)
2587 : Type(Complex, CanonicalPtr, Element->getDependence()),
2588 ElementType(Element) {}
2589
2590public:
2591 QualType getElementType() const { return ElementType; }
2592
2593 bool isSugared() const { return false; }
2594 QualType desugar() const { return QualType(this, 0); }
2595
2596 void Profile(llvm::FoldingSetNodeID &ID) {
2597 Profile(ID, getElementType());
2598 }
2599
2600 static void Profile(llvm::FoldingSetNodeID &ID, QualType Element) {
2601 ID.AddPointer(Element.getAsOpaquePtr());
2602 }
2603
2604 static bool classof(const Type *T) { return T->getTypeClass() == Complex; }
2605};
2606
2607/// Sugar for parentheses used when specifying types.
2608class ParenType : public Type, public llvm::FoldingSetNode {
2609 friend class ASTContext; // ASTContext creates these.
2610
2611 QualType Inner;
2612
2613 ParenType(QualType InnerType, QualType CanonType)
2614 : Type(Paren, CanonType, InnerType->getDependence()), Inner(InnerType) {}
2615
2616public:
2617 QualType getInnerType() const { return Inner; }
2618
2619 bool isSugared() const { return true; }
2620 QualType desugar() const { return getInnerType(); }
2621
2622 void Profile(llvm::FoldingSetNodeID &ID) {
2623 Profile(ID, getInnerType());
2624 }
2625
2626 static void Profile(llvm::FoldingSetNodeID &ID, QualType Inner) {
2627 Inner.Profile(ID);
2628 }
2629
2630 static bool classof(const Type *T) { return T->getTypeClass() == Paren; }
2631};
2632
2633/// PointerType - C99 6.7.5.1 - Pointer Declarators.
2634class PointerType : public Type, public llvm::FoldingSetNode {
2635 friend class ASTContext; // ASTContext creates these.
2636
2637 QualType PointeeType;
2638
2639 PointerType(QualType Pointee, QualType CanonicalPtr)
2640 : Type(Pointer, CanonicalPtr, Pointee->getDependence()),
2641 PointeeType(Pointee) {}
2642
2643public:
2644 QualType getPointeeType() const { return PointeeType; }
2645
2646 bool isSugared() const { return false; }
2647 QualType desugar() const { return QualType(this, 0); }
2648
2649 void Profile(llvm::FoldingSetNodeID &ID) {
2650 Profile(ID, getPointeeType());
2651 }
2652
2653 static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2654 ID.AddPointer(Pointee.getAsOpaquePtr());
2655 }
2656
2657 static bool classof(const Type *T) { return T->getTypeClass() == Pointer; }
2658};
2659
2660/// Represents a type which was implicitly adjusted by the semantic
2661/// engine for arbitrary reasons. For example, array and function types can
2662/// decay, and function types can have their calling conventions adjusted.
2663class AdjustedType : public Type, public llvm::FoldingSetNode {
2664 QualType OriginalTy;
2665 QualType AdjustedTy;
2666
2667protected:
2668 friend class ASTContext; // ASTContext creates these.
2669
2670 AdjustedType(TypeClass TC, QualType OriginalTy, QualType AdjustedTy,
2671 QualType CanonicalPtr)
2672 : Type(TC, CanonicalPtr, OriginalTy->getDependence()),
2673 OriginalTy(OriginalTy), AdjustedTy(AdjustedTy) {}
2674
2675public:
2676 QualType getOriginalType() const { return OriginalTy; }
2677 QualType getAdjustedType() const { return AdjustedTy; }
2678
2679 bool isSugared() const { return true; }
2680 QualType desugar() const { return AdjustedTy; }
2681
2682 void Profile(llvm::FoldingSetNodeID &ID) {
2683 Profile(ID, OriginalTy, AdjustedTy);
2684 }
2685
2686 static void Profile(llvm::FoldingSetNodeID &ID, QualType Orig, QualType New) {
2687 ID.AddPointer(Orig.getAsOpaquePtr());
2688 ID.AddPointer(New.getAsOpaquePtr());
2689 }
2690
2691 static bool classof(const Type *T) {
2692 return T->getTypeClass() == Adjusted || T->getTypeClass() == Decayed;
2693 }
2694};
2695
2696/// Represents a pointer type decayed from an array or function type.
2697class DecayedType : public AdjustedType {
2698 friend class ASTContext; // ASTContext creates these.
2699
2700 inline
2701 DecayedType(QualType OriginalType, QualType Decayed, QualType Canonical);
2702
2703public:
2704 QualType getDecayedType() const { return getAdjustedType(); }
2705
2706 inline QualType getPointeeType() const;
2707
2708 static bool classof(const Type *T) { return T->getTypeClass() == Decayed; }
2709};
2710
2711/// Pointer to a block type.
2712/// This type is to represent types syntactically represented as
2713/// "void (^)(int)", etc. Pointee is required to always be a function type.
2714class BlockPointerType : public Type, public llvm::FoldingSetNode {
2715 friend class ASTContext; // ASTContext creates these.
2716
2717 // Block is some kind of pointer type
2718 QualType PointeeType;
2719
2720 BlockPointerType(QualType Pointee, QualType CanonicalCls)
2721 : Type(BlockPointer, CanonicalCls, Pointee->getDependence()),
2722 PointeeType(Pointee) {}
2723
2724public:
2725 // Get the pointee type. Pointee is required to always be a function type.
2726 QualType getPointeeType() const { return PointeeType; }
2727
2728 bool isSugared() const { return false; }
2729 QualType desugar() const { return QualType(this, 0); }
2730
2731 void Profile(llvm::FoldingSetNodeID &ID) {
2732 Profile(ID, getPointeeType());
2733 }
2734
2735 static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
2736 ID.AddPointer(Pointee.getAsOpaquePtr());
2737 }
2738
2739 static bool classof(const Type *T) {
2740 return T->getTypeClass() == BlockPointer;
2741 }
2742};
2743
2744/// Base for LValueReferenceType and RValueReferenceType
2745class ReferenceType : public Type, public llvm::FoldingSetNode {
2746 QualType PointeeType;
2747
2748protected:
2749 ReferenceType(TypeClass tc, QualType Referencee, QualType CanonicalRef,
2750 bool SpelledAsLValue)
2751 : Type(tc, CanonicalRef, Referencee->getDependence()),
2752 PointeeType(Referencee) {
2753 ReferenceTypeBits.SpelledAsLValue = SpelledAsLValue;
2754 ReferenceTypeBits.InnerRef = Referencee->isReferenceType();
2755 }
2756
2757public:
2758 bool isSpelledAsLValue() const { return ReferenceTypeBits.SpelledAsLValue; }
2759 bool isInnerRef() const { return ReferenceTypeBits.InnerRef; }
2760
2761 QualType getPointeeTypeAsWritten() const { return PointeeType; }
2762
2763 QualType getPointeeType() const {
2764 // FIXME: this might strip inner qualifiers; okay?
2765 const ReferenceType *T = this;
2766 while (T->isInnerRef())
2767 T = T->PointeeType->castAs<ReferenceType>();
2768 return T->PointeeType;
2769 }
2770
2771 void Profile(llvm::FoldingSetNodeID &ID) {
2772 Profile(ID, PointeeType, isSpelledAsLValue());
2773 }
2774
2775 static void Profile(llvm::FoldingSetNodeID &ID,
2776 QualType Referencee,
2777 bool SpelledAsLValue) {
2778 ID.AddPointer(Referencee.getAsOpaquePtr());
2779 ID.AddBoolean(SpelledAsLValue);
2780 }
2781
2782 static bool classof(const Type *T) {
2783 return T->getTypeClass() == LValueReference ||
2784 T->getTypeClass() == RValueReference;
2785 }
2786};
2787
2788/// An lvalue reference type, per C++11 [dcl.ref].
2789class LValueReferenceType : public ReferenceType {
2790 friend class ASTContext; // ASTContext creates these
2791
2792 LValueReferenceType(QualType Referencee, QualType CanonicalRef,
2793 bool SpelledAsLValue)