| File: | clang/lib/Sema/SemaDecl.cpp |
| Warning: | line 16884, column 7 Called C++ object pointer is null |
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| 1 | //===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// |
| 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 declarations. |
| 10 | // |
| 11 | //===----------------------------------------------------------------------===// |
| 12 | |
| 13 | #include "TypeLocBuilder.h" |
| 14 | #include "clang/AST/ASTConsumer.h" |
| 15 | #include "clang/AST/ASTContext.h" |
| 16 | #include "clang/AST/ASTLambda.h" |
| 17 | #include "clang/AST/CXXInheritance.h" |
| 18 | #include "clang/AST/CharUnits.h" |
| 19 | #include "clang/AST/CommentDiagnostic.h" |
| 20 | #include "clang/AST/DeclCXX.h" |
| 21 | #include "clang/AST/DeclObjC.h" |
| 22 | #include "clang/AST/DeclTemplate.h" |
| 23 | #include "clang/AST/EvaluatedExprVisitor.h" |
| 24 | #include "clang/AST/Expr.h" |
| 25 | #include "clang/AST/ExprCXX.h" |
| 26 | #include "clang/AST/NonTrivialTypeVisitor.h" |
| 27 | #include "clang/AST/StmtCXX.h" |
| 28 | #include "clang/Basic/Builtins.h" |
| 29 | #include "clang/Basic/PartialDiagnostic.h" |
| 30 | #include "clang/Basic/SourceManager.h" |
| 31 | #include "clang/Basic/TargetInfo.h" |
| 32 | #include "clang/Lex/HeaderSearch.h" // TODO: Sema shouldn't depend on Lex |
| 33 | #include "clang/Lex/Lexer.h" // TODO: Extract static functions to fix layering. |
| 34 | #include "clang/Lex/ModuleLoader.h" // TODO: Sema shouldn't depend on Lex |
| 35 | #include "clang/Lex/Preprocessor.h" // Included for isCodeCompletionEnabled() |
| 36 | #include "clang/Sema/CXXFieldCollector.h" |
| 37 | #include "clang/Sema/DeclSpec.h" |
| 38 | #include "clang/Sema/DelayedDiagnostic.h" |
| 39 | #include "clang/Sema/Initialization.h" |
| 40 | #include "clang/Sema/Lookup.h" |
| 41 | #include "clang/Sema/ParsedTemplate.h" |
| 42 | #include "clang/Sema/Scope.h" |
| 43 | #include "clang/Sema/ScopeInfo.h" |
| 44 | #include "clang/Sema/SemaInternal.h" |
| 45 | #include "clang/Sema/Template.h" |
| 46 | #include "llvm/ADT/SmallString.h" |
| 47 | #include "llvm/ADT/Triple.h" |
| 48 | #include <algorithm> |
| 49 | #include <cstring> |
| 50 | #include <functional> |
| 51 | #include <unordered_map> |
| 52 | |
| 53 | using namespace clang; |
| 54 | using namespace sema; |
| 55 | |
| 56 | Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType) { |
| 57 | if (OwnedType) { |
| 58 | Decl *Group[2] = { OwnedType, Ptr }; |
| 59 | return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, 2)); |
| 60 | } |
| 61 | |
| 62 | return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); |
| 63 | } |
| 64 | |
| 65 | namespace { |
| 66 | |
| 67 | class TypeNameValidatorCCC final : public CorrectionCandidateCallback { |
| 68 | public: |
| 69 | TypeNameValidatorCCC(bool AllowInvalid, bool WantClass = false, |
| 70 | bool AllowTemplates = false, |
| 71 | bool AllowNonTemplates = true) |
| 72 | : AllowInvalidDecl(AllowInvalid), WantClassName(WantClass), |
| 73 | AllowTemplates(AllowTemplates), AllowNonTemplates(AllowNonTemplates) { |
| 74 | WantExpressionKeywords = false; |
| 75 | WantCXXNamedCasts = false; |
| 76 | WantRemainingKeywords = false; |
| 77 | } |
| 78 | |
| 79 | bool ValidateCandidate(const TypoCorrection &candidate) override { |
| 80 | if (NamedDecl *ND = candidate.getCorrectionDecl()) { |
| 81 | if (!AllowInvalidDecl && ND->isInvalidDecl()) |
| 82 | return false; |
| 83 | |
| 84 | if (getAsTypeTemplateDecl(ND)) |
| 85 | return AllowTemplates; |
| 86 | |
| 87 | bool IsType = isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND); |
| 88 | if (!IsType) |
| 89 | return false; |
| 90 | |
| 91 | if (AllowNonTemplates) |
| 92 | return true; |
| 93 | |
| 94 | // An injected-class-name of a class template (specialization) is valid |
| 95 | // as a template or as a non-template. |
| 96 | if (AllowTemplates) { |
| 97 | auto *RD = dyn_cast<CXXRecordDecl>(ND); |
| 98 | if (!RD || !RD->isInjectedClassName()) |
| 99 | return false; |
| 100 | RD = cast<CXXRecordDecl>(RD->getDeclContext()); |
| 101 | return RD->getDescribedClassTemplate() || |
| 102 | isa<ClassTemplateSpecializationDecl>(RD); |
| 103 | } |
| 104 | |
| 105 | return false; |
| 106 | } |
| 107 | |
| 108 | return !WantClassName && candidate.isKeyword(); |
| 109 | } |
| 110 | |
| 111 | std::unique_ptr<CorrectionCandidateCallback> clone() override { |
| 112 | return std::make_unique<TypeNameValidatorCCC>(*this); |
| 113 | } |
| 114 | |
| 115 | private: |
| 116 | bool AllowInvalidDecl; |
| 117 | bool WantClassName; |
| 118 | bool AllowTemplates; |
| 119 | bool AllowNonTemplates; |
| 120 | }; |
| 121 | |
| 122 | } // end anonymous namespace |
| 123 | |
| 124 | /// Determine whether the token kind starts a simple-type-specifier. |
| 125 | bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const { |
| 126 | switch (Kind) { |
| 127 | // FIXME: Take into account the current language when deciding whether a |
| 128 | // token kind is a valid type specifier |
| 129 | case tok::kw_short: |
| 130 | case tok::kw_long: |
| 131 | case tok::kw___int64: |
| 132 | case tok::kw___int128: |
| 133 | case tok::kw_signed: |
| 134 | case tok::kw_unsigned: |
| 135 | case tok::kw_void: |
| 136 | case tok::kw_char: |
| 137 | case tok::kw_int: |
| 138 | case tok::kw_half: |
| 139 | case tok::kw_float: |
| 140 | case tok::kw_double: |
| 141 | case tok::kw___bf16: |
| 142 | case tok::kw__Float16: |
| 143 | case tok::kw___float128: |
| 144 | case tok::kw_wchar_t: |
| 145 | case tok::kw_bool: |
| 146 | case tok::kw___underlying_type: |
| 147 | case tok::kw___auto_type: |
| 148 | return true; |
| 149 | |
| 150 | case tok::annot_typename: |
| 151 | case tok::kw_char16_t: |
| 152 | case tok::kw_char32_t: |
| 153 | case tok::kw_typeof: |
| 154 | case tok::annot_decltype: |
| 155 | case tok::kw_decltype: |
| 156 | return getLangOpts().CPlusPlus; |
| 157 | |
| 158 | case tok::kw_char8_t: |
| 159 | return getLangOpts().Char8; |
| 160 | |
| 161 | default: |
| 162 | break; |
| 163 | } |
| 164 | |
| 165 | return false; |
| 166 | } |
| 167 | |
| 168 | namespace { |
| 169 | enum class UnqualifiedTypeNameLookupResult { |
| 170 | NotFound, |
| 171 | FoundNonType, |
| 172 | FoundType |
| 173 | }; |
| 174 | } // end anonymous namespace |
| 175 | |
| 176 | /// Tries to perform unqualified lookup of the type decls in bases for |
| 177 | /// dependent class. |
| 178 | /// \return \a NotFound if no any decls is found, \a FoundNotType if found not a |
| 179 | /// type decl, \a FoundType if only type decls are found. |
| 180 | static UnqualifiedTypeNameLookupResult |
| 181 | lookupUnqualifiedTypeNameInBase(Sema &S, const IdentifierInfo &II, |
| 182 | SourceLocation NameLoc, |
| 183 | const CXXRecordDecl *RD) { |
| 184 | if (!RD->hasDefinition()) |
| 185 | return UnqualifiedTypeNameLookupResult::NotFound; |
| 186 | // Look for type decls in base classes. |
| 187 | UnqualifiedTypeNameLookupResult FoundTypeDecl = |
| 188 | UnqualifiedTypeNameLookupResult::NotFound; |
| 189 | for (const auto &Base : RD->bases()) { |
| 190 | const CXXRecordDecl *BaseRD = nullptr; |
| 191 | if (auto *BaseTT = Base.getType()->getAs<TagType>()) |
| 192 | BaseRD = BaseTT->getAsCXXRecordDecl(); |
| 193 | else if (auto *TST = Base.getType()->getAs<TemplateSpecializationType>()) { |
| 194 | // Look for type decls in dependent base classes that have known primary |
| 195 | // templates. |
| 196 | if (!TST || !TST->isDependentType()) |
| 197 | continue; |
| 198 | auto *TD = TST->getTemplateName().getAsTemplateDecl(); |
| 199 | if (!TD) |
| 200 | continue; |
| 201 | if (auto *BasePrimaryTemplate = |
| 202 | dyn_cast_or_null<CXXRecordDecl>(TD->getTemplatedDecl())) { |
| 203 | if (BasePrimaryTemplate->getCanonicalDecl() != RD->getCanonicalDecl()) |
| 204 | BaseRD = BasePrimaryTemplate; |
| 205 | else if (auto *CTD = dyn_cast<ClassTemplateDecl>(TD)) { |
| 206 | if (const ClassTemplatePartialSpecializationDecl *PS = |
| 207 | CTD->findPartialSpecialization(Base.getType())) |
| 208 | if (PS->getCanonicalDecl() != RD->getCanonicalDecl()) |
| 209 | BaseRD = PS; |
| 210 | } |
| 211 | } |
| 212 | } |
| 213 | if (BaseRD) { |
| 214 | for (NamedDecl *ND : BaseRD->lookup(&II)) { |
| 215 | if (!isa<TypeDecl>(ND)) |
| 216 | return UnqualifiedTypeNameLookupResult::FoundNonType; |
| 217 | FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType; |
| 218 | } |
| 219 | if (FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound) { |
| 220 | switch (lookupUnqualifiedTypeNameInBase(S, II, NameLoc, BaseRD)) { |
| 221 | case UnqualifiedTypeNameLookupResult::FoundNonType: |
| 222 | return UnqualifiedTypeNameLookupResult::FoundNonType; |
| 223 | case UnqualifiedTypeNameLookupResult::FoundType: |
| 224 | FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType; |
| 225 | break; |
| 226 | case UnqualifiedTypeNameLookupResult::NotFound: |
| 227 | break; |
| 228 | } |
| 229 | } |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | return FoundTypeDecl; |
| 234 | } |
| 235 | |
| 236 | static ParsedType recoverFromTypeInKnownDependentBase(Sema &S, |
| 237 | const IdentifierInfo &II, |
| 238 | SourceLocation NameLoc) { |
| 239 | // Lookup in the parent class template context, if any. |
| 240 | const CXXRecordDecl *RD = nullptr; |
| 241 | UnqualifiedTypeNameLookupResult FoundTypeDecl = |
| 242 | UnqualifiedTypeNameLookupResult::NotFound; |
| 243 | for (DeclContext *DC = S.CurContext; |
| 244 | DC && FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound; |
| 245 | DC = DC->getParent()) { |
| 246 | // Look for type decls in dependent base classes that have known primary |
| 247 | // templates. |
| 248 | RD = dyn_cast<CXXRecordDecl>(DC); |
| 249 | if (RD && RD->getDescribedClassTemplate()) |
| 250 | FoundTypeDecl = lookupUnqualifiedTypeNameInBase(S, II, NameLoc, RD); |
| 251 | } |
| 252 | if (FoundTypeDecl != UnqualifiedTypeNameLookupResult::FoundType) |
| 253 | return nullptr; |
| 254 | |
| 255 | // We found some types in dependent base classes. Recover as if the user |
| 256 | // wrote 'typename MyClass::II' instead of 'II'. We'll fully resolve the |
| 257 | // lookup during template instantiation. |
| 258 | S.Diag(NameLoc, diag::ext_found_in_dependent_base) << &II; |
| 259 | |
| 260 | ASTContext &Context = S.Context; |
| 261 | auto *NNS = NestedNameSpecifier::Create(Context, nullptr, false, |
| 262 | cast<Type>(Context.getRecordType(RD))); |
| 263 | QualType T = Context.getDependentNameType(ETK_Typename, NNS, &II); |
| 264 | |
| 265 | CXXScopeSpec SS; |
| 266 | SS.MakeTrivial(Context, NNS, SourceRange(NameLoc)); |
| 267 | |
| 268 | TypeLocBuilder Builder; |
| 269 | DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T); |
| 270 | DepTL.setNameLoc(NameLoc); |
| 271 | DepTL.setElaboratedKeywordLoc(SourceLocation()); |
| 272 | DepTL.setQualifierLoc(SS.getWithLocInContext(Context)); |
| 273 | return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); |
| 274 | } |
| 275 | |
| 276 | /// If the identifier refers to a type name within this scope, |
| 277 | /// return the declaration of that type. |
| 278 | /// |
| 279 | /// This routine performs ordinary name lookup of the identifier II |
| 280 | /// within the given scope, with optional C++ scope specifier SS, to |
| 281 | /// determine whether the name refers to a type. If so, returns an |
| 282 | /// opaque pointer (actually a QualType) corresponding to that |
| 283 | /// type. Otherwise, returns NULL. |
| 284 | ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc, |
| 285 | Scope *S, CXXScopeSpec *SS, |
| 286 | bool isClassName, bool HasTrailingDot, |
| 287 | ParsedType ObjectTypePtr, |
| 288 | bool IsCtorOrDtorName, |
| 289 | bool WantNontrivialTypeSourceInfo, |
| 290 | bool IsClassTemplateDeductionContext, |
| 291 | IdentifierInfo **CorrectedII) { |
| 292 | // FIXME: Consider allowing this outside C++1z mode as an extension. |
| 293 | bool AllowDeducedTemplate = IsClassTemplateDeductionContext && |
| 294 | getLangOpts().CPlusPlus17 && !IsCtorOrDtorName && |
| 295 | !isClassName && !HasTrailingDot; |
| 296 | |
| 297 | // Determine where we will perform name lookup. |
| 298 | DeclContext *LookupCtx = nullptr; |
| 299 | if (ObjectTypePtr) { |
| 300 | QualType ObjectType = ObjectTypePtr.get(); |
| 301 | if (ObjectType->isRecordType()) |
| 302 | LookupCtx = computeDeclContext(ObjectType); |
| 303 | } else if (SS && SS->isNotEmpty()) { |
| 304 | LookupCtx = computeDeclContext(*SS, false); |
| 305 | |
| 306 | if (!LookupCtx) { |
| 307 | if (isDependentScopeSpecifier(*SS)) { |
| 308 | // C++ [temp.res]p3: |
| 309 | // A qualified-id that refers to a type and in which the |
| 310 | // nested-name-specifier depends on a template-parameter (14.6.2) |
| 311 | // shall be prefixed by the keyword typename to indicate that the |
| 312 | // qualified-id denotes a type, forming an |
| 313 | // elaborated-type-specifier (7.1.5.3). |
| 314 | // |
| 315 | // We therefore do not perform any name lookup if the result would |
| 316 | // refer to a member of an unknown specialization. |
| 317 | if (!isClassName && !IsCtorOrDtorName) |
| 318 | return nullptr; |
| 319 | |
| 320 | // We know from the grammar that this name refers to a type, |
| 321 | // so build a dependent node to describe the type. |
| 322 | if (WantNontrivialTypeSourceInfo) |
| 323 | return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); |
| 324 | |
| 325 | NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); |
| 326 | QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, |
| 327 | II, NameLoc); |
| 328 | return ParsedType::make(T); |
| 329 | } |
| 330 | |
| 331 | return nullptr; |
| 332 | } |
| 333 | |
| 334 | if (!LookupCtx->isDependentContext() && |
| 335 | RequireCompleteDeclContext(*SS, LookupCtx)) |
| 336 | return nullptr; |
| 337 | } |
| 338 | |
| 339 | // FIXME: LookupNestedNameSpecifierName isn't the right kind of |
| 340 | // lookup for class-names. |
| 341 | LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : |
| 342 | LookupOrdinaryName; |
| 343 | LookupResult Result(*this, &II, NameLoc, Kind); |
| 344 | if (LookupCtx) { |
| 345 | // Perform "qualified" name lookup into the declaration context we |
| 346 | // computed, which is either the type of the base of a member access |
| 347 | // expression or the declaration context associated with a prior |
| 348 | // nested-name-specifier. |
| 349 | LookupQualifiedName(Result, LookupCtx); |
| 350 | |
| 351 | if (ObjectTypePtr && Result.empty()) { |
| 352 | // C++ [basic.lookup.classref]p3: |
| 353 | // If the unqualified-id is ~type-name, the type-name is looked up |
| 354 | // in the context of the entire postfix-expression. If the type T of |
| 355 | // the object expression is of a class type C, the type-name is also |
| 356 | // looked up in the scope of class C. At least one of the lookups shall |
| 357 | // find a name that refers to (possibly cv-qualified) T. |
| 358 | LookupName(Result, S); |
| 359 | } |
| 360 | } else { |
| 361 | // Perform unqualified name lookup. |
| 362 | LookupName(Result, S); |
| 363 | |
| 364 | // For unqualified lookup in a class template in MSVC mode, look into |
| 365 | // dependent base classes where the primary class template is known. |
| 366 | if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) { |
| 367 | if (ParsedType TypeInBase = |
| 368 | recoverFromTypeInKnownDependentBase(*this, II, NameLoc)) |
| 369 | return TypeInBase; |
| 370 | } |
| 371 | } |
| 372 | |
| 373 | NamedDecl *IIDecl = nullptr; |
| 374 | switch (Result.getResultKind()) { |
| 375 | case LookupResult::NotFound: |
| 376 | case LookupResult::NotFoundInCurrentInstantiation: |
| 377 | if (CorrectedII) { |
| 378 | TypeNameValidatorCCC CCC(/*AllowInvalid=*/true, isClassName, |
| 379 | AllowDeducedTemplate); |
| 380 | TypoCorrection Correction = CorrectTypo(Result.getLookupNameInfo(), Kind, |
| 381 | S, SS, CCC, CTK_ErrorRecovery); |
| 382 | IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo(); |
| 383 | TemplateTy Template; |
| 384 | bool MemberOfUnknownSpecialization; |
| 385 | UnqualifiedId TemplateName; |
| 386 | TemplateName.setIdentifier(NewII, NameLoc); |
| 387 | NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier(); |
| 388 | CXXScopeSpec NewSS, *NewSSPtr = SS; |
| 389 | if (SS && NNS) { |
| 390 | NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc)); |
| 391 | NewSSPtr = &NewSS; |
| 392 | } |
| 393 | if (Correction && (NNS || NewII != &II) && |
| 394 | // Ignore a correction to a template type as the to-be-corrected |
| 395 | // identifier is not a template (typo correction for template names |
| 396 | // is handled elsewhere). |
| 397 | !(getLangOpts().CPlusPlus && NewSSPtr && |
| 398 | isTemplateName(S, *NewSSPtr, false, TemplateName, nullptr, false, |
| 399 | Template, MemberOfUnknownSpecialization))) { |
| 400 | ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr, |
| 401 | isClassName, HasTrailingDot, ObjectTypePtr, |
| 402 | IsCtorOrDtorName, |
| 403 | WantNontrivialTypeSourceInfo, |
| 404 | IsClassTemplateDeductionContext); |
| 405 | if (Ty) { |
| 406 | diagnoseTypo(Correction, |
| 407 | PDiag(diag::err_unknown_type_or_class_name_suggest) |
| 408 | << Result.getLookupName() << isClassName); |
| 409 | if (SS && NNS) |
| 410 | SS->MakeTrivial(Context, NNS, SourceRange(NameLoc)); |
| 411 | *CorrectedII = NewII; |
| 412 | return Ty; |
| 413 | } |
| 414 | } |
| 415 | } |
| 416 | // If typo correction failed or was not performed, fall through |
| 417 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
| 418 | case LookupResult::FoundOverloaded: |
| 419 | case LookupResult::FoundUnresolvedValue: |
| 420 | Result.suppressDiagnostics(); |
| 421 | return nullptr; |
| 422 | |
| 423 | case LookupResult::Ambiguous: |
| 424 | // Recover from type-hiding ambiguities by hiding the type. We'll |
| 425 | // do the lookup again when looking for an object, and we can |
| 426 | // diagnose the error then. If we don't do this, then the error |
| 427 | // about hiding the type will be immediately followed by an error |
| 428 | // that only makes sense if the identifier was treated like a type. |
| 429 | if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { |
| 430 | Result.suppressDiagnostics(); |
| 431 | return nullptr; |
| 432 | } |
| 433 | |
| 434 | // Look to see if we have a type anywhere in the list of results. |
| 435 | for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); |
| 436 | Res != ResEnd; ++Res) { |
| 437 | NamedDecl *RealRes = (*Res)->getUnderlyingDecl(); |
| 438 | if (isa<TypeDecl, ObjCInterfaceDecl, UnresolvedUsingIfExistsDecl>( |
| 439 | RealRes) || |
| 440 | (AllowDeducedTemplate && getAsTypeTemplateDecl(RealRes))) { |
| 441 | if (!IIDecl || |
| 442 | // Make the selection of the recovery decl deterministic. |
| 443 | RealRes->getLocation() < IIDecl->getLocation()) |
| 444 | IIDecl = RealRes; |
| 445 | } |
| 446 | } |
| 447 | |
| 448 | if (!IIDecl) { |
| 449 | // None of the entities we found is a type, so there is no way |
| 450 | // to even assume that the result is a type. In this case, don't |
| 451 | // complain about the ambiguity. The parser will either try to |
| 452 | // perform this lookup again (e.g., as an object name), which |
| 453 | // will produce the ambiguity, or will complain that it expected |
| 454 | // a type name. |
| 455 | Result.suppressDiagnostics(); |
| 456 | return nullptr; |
| 457 | } |
| 458 | |
| 459 | // We found a type within the ambiguous lookup; diagnose the |
| 460 | // ambiguity and then return that type. This might be the right |
| 461 | // answer, or it might not be, but it suppresses any attempt to |
| 462 | // perform the name lookup again. |
| 463 | break; |
| 464 | |
| 465 | case LookupResult::Found: |
| 466 | IIDecl = Result.getFoundDecl(); |
| 467 | break; |
| 468 | } |
| 469 | |
| 470 | assert(IIDecl && "Didn't find decl")(static_cast<void> (0)); |
| 471 | |
| 472 | QualType T; |
| 473 | if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { |
| 474 | // C++ [class.qual]p2: A lookup that would find the injected-class-name |
| 475 | // instead names the constructors of the class, except when naming a class. |
| 476 | // This is ill-formed when we're not actually forming a ctor or dtor name. |
| 477 | auto *LookupRD = dyn_cast_or_null<CXXRecordDecl>(LookupCtx); |
| 478 | auto *FoundRD = dyn_cast<CXXRecordDecl>(TD); |
| 479 | if (!isClassName && !IsCtorOrDtorName && LookupRD && FoundRD && |
| 480 | FoundRD->isInjectedClassName() && |
| 481 | declaresSameEntity(LookupRD, cast<Decl>(FoundRD->getParent()))) |
| 482 | Diag(NameLoc, diag::err_out_of_line_qualified_id_type_names_constructor) |
| 483 | << &II << /*Type*/1; |
| 484 | |
| 485 | DiagnoseUseOfDecl(IIDecl, NameLoc); |
| 486 | |
| 487 | T = Context.getTypeDeclType(TD); |
| 488 | MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false); |
| 489 | } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { |
| 490 | (void)DiagnoseUseOfDecl(IDecl, NameLoc); |
| 491 | if (!HasTrailingDot) |
| 492 | T = Context.getObjCInterfaceType(IDecl); |
| 493 | } else if (auto *UD = dyn_cast<UnresolvedUsingIfExistsDecl>(IIDecl)) { |
| 494 | (void)DiagnoseUseOfDecl(UD, NameLoc); |
| 495 | // Recover with 'int' |
| 496 | T = Context.IntTy; |
| 497 | } else if (AllowDeducedTemplate) { |
| 498 | if (auto *TD = getAsTypeTemplateDecl(IIDecl)) |
| 499 | T = Context.getDeducedTemplateSpecializationType(TemplateName(TD), |
| 500 | QualType(), false); |
| 501 | } |
| 502 | |
| 503 | if (T.isNull()) { |
| 504 | // If it's not plausibly a type, suppress diagnostics. |
| 505 | Result.suppressDiagnostics(); |
| 506 | return nullptr; |
| 507 | } |
| 508 | |
| 509 | // NOTE: avoid constructing an ElaboratedType(Loc) if this is a |
| 510 | // constructor or destructor name (in such a case, the scope specifier |
| 511 | // will be attached to the enclosing Expr or Decl node). |
| 512 | if (SS && SS->isNotEmpty() && !IsCtorOrDtorName && |
| 513 | !isa<ObjCInterfaceDecl, UnresolvedUsingIfExistsDecl>(IIDecl)) { |
| 514 | if (WantNontrivialTypeSourceInfo) { |
| 515 | // Construct a type with type-source information. |
| 516 | TypeLocBuilder Builder; |
| 517 | Builder.pushTypeSpec(T).setNameLoc(NameLoc); |
| 518 | |
| 519 | T = getElaboratedType(ETK_None, *SS, T); |
| 520 | ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); |
| 521 | ElabTL.setElaboratedKeywordLoc(SourceLocation()); |
| 522 | ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); |
| 523 | return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); |
| 524 | } else { |
| 525 | T = getElaboratedType(ETK_None, *SS, T); |
| 526 | } |
| 527 | } |
| 528 | |
| 529 | return ParsedType::make(T); |
| 530 | } |
| 531 | |
| 532 | // Builds a fake NNS for the given decl context. |
| 533 | static NestedNameSpecifier * |
| 534 | synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) { |
| 535 | for (;; DC = DC->getLookupParent()) { |
| 536 | DC = DC->getPrimaryContext(); |
| 537 | auto *ND = dyn_cast<NamespaceDecl>(DC); |
| 538 | if (ND && !ND->isInline() && !ND->isAnonymousNamespace()) |
| 539 | return NestedNameSpecifier::Create(Context, nullptr, ND); |
| 540 | else if (auto *RD = dyn_cast<CXXRecordDecl>(DC)) |
| 541 | return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(), |
| 542 | RD->getTypeForDecl()); |
| 543 | else if (isa<TranslationUnitDecl>(DC)) |
| 544 | return NestedNameSpecifier::GlobalSpecifier(Context); |
| 545 | } |
| 546 | llvm_unreachable("something isn't in TU scope?")__builtin_unreachable(); |
| 547 | } |
| 548 | |
| 549 | /// Find the parent class with dependent bases of the innermost enclosing method |
| 550 | /// context. Do not look for enclosing CXXRecordDecls directly, or we will end |
| 551 | /// up allowing unqualified dependent type names at class-level, which MSVC |
| 552 | /// correctly rejects. |
| 553 | static const CXXRecordDecl * |
| 554 | findRecordWithDependentBasesOfEnclosingMethod(const DeclContext *DC) { |
| 555 | for (; DC && DC->isDependentContext(); DC = DC->getLookupParent()) { |
| 556 | DC = DC->getPrimaryContext(); |
| 557 | if (const auto *MD = dyn_cast<CXXMethodDecl>(DC)) |
| 558 | if (MD->getParent()->hasAnyDependentBases()) |
| 559 | return MD->getParent(); |
| 560 | } |
| 561 | return nullptr; |
| 562 | } |
| 563 | |
| 564 | ParsedType Sema::ActOnMSVCUnknownTypeName(const IdentifierInfo &II, |
| 565 | SourceLocation NameLoc, |
| 566 | bool IsTemplateTypeArg) { |
| 567 | assert(getLangOpts().MSVCCompat && "shouldn't be called in non-MSVC mode")(static_cast<void> (0)); |
| 568 | |
| 569 | NestedNameSpecifier *NNS = nullptr; |
| 570 | if (IsTemplateTypeArg && getCurScope()->isTemplateParamScope()) { |
| 571 | // If we weren't able to parse a default template argument, delay lookup |
| 572 | // until instantiation time by making a non-dependent DependentTypeName. We |
| 573 | // pretend we saw a NestedNameSpecifier referring to the current scope, and |
| 574 | // lookup is retried. |
| 575 | // FIXME: This hurts our diagnostic quality, since we get errors like "no |
| 576 | // type named 'Foo' in 'current_namespace'" when the user didn't write any |
| 577 | // name specifiers. |
| 578 | NNS = synthesizeCurrentNestedNameSpecifier(Context, CurContext); |
| 579 | Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II; |
| 580 | } else if (const CXXRecordDecl *RD = |
| 581 | findRecordWithDependentBasesOfEnclosingMethod(CurContext)) { |
| 582 | // Build a DependentNameType that will perform lookup into RD at |
| 583 | // instantiation time. |
| 584 | NNS = NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(), |
| 585 | RD->getTypeForDecl()); |
| 586 | |
| 587 | // Diagnose that this identifier was undeclared, and retry the lookup during |
| 588 | // template instantiation. |
| 589 | Diag(NameLoc, diag::ext_undeclared_unqual_id_with_dependent_base) << &II |
| 590 | << RD; |
| 591 | } else { |
| 592 | // This is not a situation that we should recover from. |
| 593 | return ParsedType(); |
| 594 | } |
| 595 | |
| 596 | QualType T = Context.getDependentNameType(ETK_None, NNS, &II); |
| 597 | |
| 598 | // Build type location information. We synthesized the qualifier, so we have |
| 599 | // to build a fake NestedNameSpecifierLoc. |
| 600 | NestedNameSpecifierLocBuilder NNSLocBuilder; |
| 601 | NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc)); |
| 602 | NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context); |
| 603 | |
| 604 | TypeLocBuilder Builder; |
| 605 | DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T); |
| 606 | DepTL.setNameLoc(NameLoc); |
| 607 | DepTL.setElaboratedKeywordLoc(SourceLocation()); |
| 608 | DepTL.setQualifierLoc(QualifierLoc); |
| 609 | return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); |
| 610 | } |
| 611 | |
| 612 | /// isTagName() - This method is called *for error recovery purposes only* |
| 613 | /// to determine if the specified name is a valid tag name ("struct foo"). If |
| 614 | /// so, this returns the TST for the tag corresponding to it (TST_enum, |
| 615 | /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose |
| 616 | /// cases in C where the user forgot to specify the tag. |
| 617 | DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { |
| 618 | // Do a tag name lookup in this scope. |
| 619 | LookupResult R(*this, &II, SourceLocation(), LookupTagName); |
| 620 | LookupName(R, S, false); |
| 621 | R.suppressDiagnostics(); |
| 622 | if (R.getResultKind() == LookupResult::Found) |
| 623 | if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { |
| 624 | switch (TD->getTagKind()) { |
| 625 | case TTK_Struct: return DeclSpec::TST_struct; |
| 626 | case TTK_Interface: return DeclSpec::TST_interface; |
| 627 | case TTK_Union: return DeclSpec::TST_union; |
| 628 | case TTK_Class: return DeclSpec::TST_class; |
| 629 | case TTK_Enum: return DeclSpec::TST_enum; |
| 630 | } |
| 631 | } |
| 632 | |
| 633 | return DeclSpec::TST_unspecified; |
| 634 | } |
| 635 | |
| 636 | /// isMicrosoftMissingTypename - In Microsoft mode, within class scope, |
| 637 | /// if a CXXScopeSpec's type is equal to the type of one of the base classes |
| 638 | /// then downgrade the missing typename error to a warning. |
| 639 | /// This is needed for MSVC compatibility; Example: |
| 640 | /// @code |
| 641 | /// template<class T> class A { |
| 642 | /// public: |
| 643 | /// typedef int TYPE; |
| 644 | /// }; |
| 645 | /// template<class T> class B : public A<T> { |
| 646 | /// public: |
| 647 | /// A<T>::TYPE a; // no typename required because A<T> is a base class. |
| 648 | /// }; |
| 649 | /// @endcode |
| 650 | bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) { |
| 651 | if (CurContext->isRecord()) { |
| 652 | if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super) |
| 653 | return true; |
| 654 | |
| 655 | const Type *Ty = SS->getScopeRep()->getAsType(); |
| 656 | |
| 657 | CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext); |
| 658 | for (const auto &Base : RD->bases()) |
| 659 | if (Ty && Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType())) |
| 660 | return true; |
| 661 | return S->isFunctionPrototypeScope(); |
| 662 | } |
| 663 | return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope(); |
| 664 | } |
| 665 | |
| 666 | void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II, |
| 667 | SourceLocation IILoc, |
| 668 | Scope *S, |
| 669 | CXXScopeSpec *SS, |
| 670 | ParsedType &SuggestedType, |
| 671 | bool IsTemplateName) { |
| 672 | // Don't report typename errors for editor placeholders. |
| 673 | if (II->isEditorPlaceholder()) |
| 674 | return; |
| 675 | // We don't have anything to suggest (yet). |
| 676 | SuggestedType = nullptr; |
| 677 | |
| 678 | // There may have been a typo in the name of the type. Look up typo |
| 679 | // results, in case we have something that we can suggest. |
| 680 | TypeNameValidatorCCC CCC(/*AllowInvalid=*/false, /*WantClass=*/false, |
| 681 | /*AllowTemplates=*/IsTemplateName, |
| 682 | /*AllowNonTemplates=*/!IsTemplateName); |
| 683 | if (TypoCorrection Corrected = |
| 684 | CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS, |
| 685 | CCC, CTK_ErrorRecovery)) { |
| 686 | // FIXME: Support error recovery for the template-name case. |
| 687 | bool CanRecover = !IsTemplateName; |
| 688 | if (Corrected.isKeyword()) { |
| 689 | // We corrected to a keyword. |
| 690 | diagnoseTypo(Corrected, |
| 691 | PDiag(IsTemplateName ? diag::err_no_template_suggest |
| 692 | : diag::err_unknown_typename_suggest) |
| 693 | << II); |
| 694 | II = Corrected.getCorrectionAsIdentifierInfo(); |
| 695 | } else { |
| 696 | // We found a similarly-named type or interface; suggest that. |
| 697 | if (!SS || !SS->isSet()) { |
| 698 | diagnoseTypo(Corrected, |
| 699 | PDiag(IsTemplateName ? diag::err_no_template_suggest |
| 700 | : diag::err_unknown_typename_suggest) |
| 701 | << II, CanRecover); |
| 702 | } else if (DeclContext *DC = computeDeclContext(*SS, false)) { |
| 703 | std::string CorrectedStr(Corrected.getAsString(getLangOpts())); |
| 704 | bool DroppedSpecifier = Corrected.WillReplaceSpecifier() && |
| 705 | II->getName().equals(CorrectedStr); |
| 706 | diagnoseTypo(Corrected, |
| 707 | PDiag(IsTemplateName |
| 708 | ? diag::err_no_member_template_suggest |
| 709 | : diag::err_unknown_nested_typename_suggest) |
| 710 | << II << DC << DroppedSpecifier << SS->getRange(), |
| 711 | CanRecover); |
| 712 | } else { |
| 713 | llvm_unreachable("could not have corrected a typo here")__builtin_unreachable(); |
| 714 | } |
| 715 | |
| 716 | if (!CanRecover) |
| 717 | return; |
| 718 | |
| 719 | CXXScopeSpec tmpSS; |
| 720 | if (Corrected.getCorrectionSpecifier()) |
| 721 | tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(), |
| 722 | SourceRange(IILoc)); |
| 723 | // FIXME: Support class template argument deduction here. |
| 724 | SuggestedType = |
| 725 | getTypeName(*Corrected.getCorrectionAsIdentifierInfo(), IILoc, S, |
| 726 | tmpSS.isSet() ? &tmpSS : SS, false, false, nullptr, |
| 727 | /*IsCtorOrDtorName=*/false, |
| 728 | /*WantNontrivialTypeSourceInfo=*/true); |
| 729 | } |
| 730 | return; |
| 731 | } |
| 732 | |
| 733 | if (getLangOpts().CPlusPlus && !IsTemplateName) { |
| 734 | // See if II is a class template that the user forgot to pass arguments to. |
| 735 | UnqualifiedId Name; |
| 736 | Name.setIdentifier(II, IILoc); |
| 737 | CXXScopeSpec EmptySS; |
| 738 | TemplateTy TemplateResult; |
| 739 | bool MemberOfUnknownSpecialization; |
| 740 | if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, |
| 741 | Name, nullptr, true, TemplateResult, |
| 742 | MemberOfUnknownSpecialization) == TNK_Type_template) { |
| 743 | diagnoseMissingTemplateArguments(TemplateResult.get(), IILoc); |
| 744 | return; |
| 745 | } |
| 746 | } |
| 747 | |
| 748 | // FIXME: Should we move the logic that tries to recover from a missing tag |
| 749 | // (struct, union, enum) from Parser::ParseImplicitInt here, instead? |
| 750 | |
| 751 | if (!SS || (!SS->isSet() && !SS->isInvalid())) |
| 752 | Diag(IILoc, IsTemplateName ? diag::err_no_template |
| 753 | : diag::err_unknown_typename) |
| 754 | << II; |
| 755 | else if (DeclContext *DC = computeDeclContext(*SS, false)) |
| 756 | Diag(IILoc, IsTemplateName ? diag::err_no_member_template |
| 757 | : diag::err_typename_nested_not_found) |
| 758 | << II << DC << SS->getRange(); |
| 759 | else if (SS->isValid() && SS->getScopeRep()->containsErrors()) { |
| 760 | SuggestedType = |
| 761 | ActOnTypenameType(S, SourceLocation(), *SS, *II, IILoc).get(); |
| 762 | } else if (isDependentScopeSpecifier(*SS)) { |
| 763 | unsigned DiagID = diag::err_typename_missing; |
| 764 | if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S)) |
| 765 | DiagID = diag::ext_typename_missing; |
| 766 | |
| 767 | Diag(SS->getRange().getBegin(), DiagID) |
| 768 | << SS->getScopeRep() << II->getName() |
| 769 | << SourceRange(SS->getRange().getBegin(), IILoc) |
| 770 | << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); |
| 771 | SuggestedType = ActOnTypenameType(S, SourceLocation(), |
| 772 | *SS, *II, IILoc).get(); |
| 773 | } else { |
| 774 | assert(SS && SS->isInvalid() &&(static_cast<void> (0)) |
| 775 | "Invalid scope specifier has already been diagnosed")(static_cast<void> (0)); |
| 776 | } |
| 777 | } |
| 778 | |
| 779 | /// Determine whether the given result set contains either a type name |
| 780 | /// or |
| 781 | static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) { |
| 782 | bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus && |
| 783 | NextToken.is(tok::less); |
| 784 | |
| 785 | for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) { |
| 786 | if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I)) |
| 787 | return true; |
| 788 | |
| 789 | if (CheckTemplate && isa<TemplateDecl>(*I)) |
| 790 | return true; |
| 791 | } |
| 792 | |
| 793 | return false; |
| 794 | } |
| 795 | |
| 796 | static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result, |
| 797 | Scope *S, CXXScopeSpec &SS, |
| 798 | IdentifierInfo *&Name, |
| 799 | SourceLocation NameLoc) { |
| 800 | LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName); |
| 801 | SemaRef.LookupParsedName(R, S, &SS); |
| 802 | if (TagDecl *Tag = R.getAsSingle<TagDecl>()) { |
| 803 | StringRef FixItTagName; |
| 804 | switch (Tag->getTagKind()) { |
| 805 | case TTK_Class: |
| 806 | FixItTagName = "class "; |
| 807 | break; |
| 808 | |
| 809 | case TTK_Enum: |
| 810 | FixItTagName = "enum "; |
| 811 | break; |
| 812 | |
| 813 | case TTK_Struct: |
| 814 | FixItTagName = "struct "; |
| 815 | break; |
| 816 | |
| 817 | case TTK_Interface: |
| 818 | FixItTagName = "__interface "; |
| 819 | break; |
| 820 | |
| 821 | case TTK_Union: |
| 822 | FixItTagName = "union "; |
| 823 | break; |
| 824 | } |
| 825 | |
| 826 | StringRef TagName = FixItTagName.drop_back(); |
| 827 | SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag) |
| 828 | << Name << TagName << SemaRef.getLangOpts().CPlusPlus |
| 829 | << FixItHint::CreateInsertion(NameLoc, FixItTagName); |
| 830 | |
| 831 | for (LookupResult::iterator I = Result.begin(), IEnd = Result.end(); |
| 832 | I != IEnd; ++I) |
| 833 | SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type) |
| 834 | << Name << TagName; |
| 835 | |
| 836 | // Replace lookup results with just the tag decl. |
| 837 | Result.clear(Sema::LookupTagName); |
| 838 | SemaRef.LookupParsedName(Result, S, &SS); |
| 839 | return true; |
| 840 | } |
| 841 | |
| 842 | return false; |
| 843 | } |
| 844 | |
| 845 | /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier. |
| 846 | static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS, |
| 847 | QualType T, SourceLocation NameLoc) { |
| 848 | ASTContext &Context = S.Context; |
| 849 | |
| 850 | TypeLocBuilder Builder; |
| 851 | Builder.pushTypeSpec(T).setNameLoc(NameLoc); |
| 852 | |
| 853 | T = S.getElaboratedType(ETK_None, SS, T); |
| 854 | ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); |
| 855 | ElabTL.setElaboratedKeywordLoc(SourceLocation()); |
| 856 | ElabTL.setQualifierLoc(SS.getWithLocInContext(Context)); |
| 857 | return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); |
| 858 | } |
| 859 | |
| 860 | Sema::NameClassification Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, |
| 861 | IdentifierInfo *&Name, |
| 862 | SourceLocation NameLoc, |
| 863 | const Token &NextToken, |
| 864 | CorrectionCandidateCallback *CCC) { |
| 865 | DeclarationNameInfo NameInfo(Name, NameLoc); |
| 866 | ObjCMethodDecl *CurMethod = getCurMethodDecl(); |
| 867 | |
| 868 | assert(NextToken.isNot(tok::coloncolon) &&(static_cast<void> (0)) |
| 869 | "parse nested name specifiers before calling ClassifyName")(static_cast<void> (0)); |
| 870 | if (getLangOpts().CPlusPlus && SS.isSet() && |
| 871 | isCurrentClassName(*Name, S, &SS)) { |
| 872 | // Per [class.qual]p2, this names the constructors of SS, not the |
| 873 | // injected-class-name. We don't have a classification for that. |
| 874 | // There's not much point caching this result, since the parser |
| 875 | // will reject it later. |
| 876 | return NameClassification::Unknown(); |
| 877 | } |
| 878 | |
| 879 | LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName); |
| 880 | LookupParsedName(Result, S, &SS, !CurMethod); |
| 881 | |
| 882 | if (SS.isInvalid()) |
| 883 | return NameClassification::Error(); |
| 884 | |
| 885 | // For unqualified lookup in a class template in MSVC mode, look into |
| 886 | // dependent base classes where the primary class template is known. |
| 887 | if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) { |
| 888 | if (ParsedType TypeInBase = |
| 889 | recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc)) |
| 890 | return TypeInBase; |
| 891 | } |
| 892 | |
| 893 | // Perform lookup for Objective-C instance variables (including automatically |
| 894 | // synthesized instance variables), if we're in an Objective-C method. |
| 895 | // FIXME: This lookup really, really needs to be folded in to the normal |
| 896 | // unqualified lookup mechanism. |
| 897 | if (SS.isEmpty() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) { |
| 898 | DeclResult Ivar = LookupIvarInObjCMethod(Result, S, Name); |
| 899 | if (Ivar.isInvalid()) |
| 900 | return NameClassification::Error(); |
| 901 | if (Ivar.isUsable()) |
| 902 | return NameClassification::NonType(cast<NamedDecl>(Ivar.get())); |
| 903 | |
| 904 | // We defer builtin creation until after ivar lookup inside ObjC methods. |
| 905 | if (Result.empty()) |
| 906 | LookupBuiltin(Result); |
| 907 | } |
| 908 | |
| 909 | bool SecondTry = false; |
| 910 | bool IsFilteredTemplateName = false; |
| 911 | |
| 912 | Corrected: |
| 913 | switch (Result.getResultKind()) { |
| 914 | case LookupResult::NotFound: |
| 915 | // If an unqualified-id is followed by a '(', then we have a function |
| 916 | // call. |
| 917 | if (SS.isEmpty() && NextToken.is(tok::l_paren)) { |
| 918 | // In C++, this is an ADL-only call. |
| 919 | // FIXME: Reference? |
| 920 | if (getLangOpts().CPlusPlus) |
| 921 | return NameClassification::UndeclaredNonType(); |
| 922 | |
| 923 | // C90 6.3.2.2: |
| 924 | // If the expression that precedes the parenthesized argument list in a |
| 925 | // function call consists solely of an identifier, and if no |
| 926 | // declaration is visible for this identifier, the identifier is |
| 927 | // implicitly declared exactly as if, in the innermost block containing |
| 928 | // the function call, the declaration |
| 929 | // |
| 930 | // extern int identifier (); |
| 931 | // |
| 932 | // appeared. |
| 933 | // |
| 934 | // We also allow this in C99 as an extension. |
| 935 | if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) |
| 936 | return NameClassification::NonType(D); |
| 937 | } |
| 938 | |
| 939 | if (getLangOpts().CPlusPlus20 && SS.isEmpty() && NextToken.is(tok::less)) { |
| 940 | // In C++20 onwards, this could be an ADL-only call to a function |
| 941 | // template, and we're required to assume that this is a template name. |
| 942 | // |
| 943 | // FIXME: Find a way to still do typo correction in this case. |
| 944 | TemplateName Template = |
| 945 | Context.getAssumedTemplateName(NameInfo.getName()); |
| 946 | return NameClassification::UndeclaredTemplate(Template); |
| 947 | } |
| 948 | |
| 949 | // In C, we first see whether there is a tag type by the same name, in |
| 950 | // which case it's likely that the user just forgot to write "enum", |
| 951 | // "struct", or "union". |
| 952 | if (!getLangOpts().CPlusPlus && !SecondTry && |
| 953 | isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) { |
| 954 | break; |
| 955 | } |
| 956 | |
| 957 | // Perform typo correction to determine if there is another name that is |
| 958 | // close to this name. |
| 959 | if (!SecondTry && CCC) { |
| 960 | SecondTry = true; |
| 961 | if (TypoCorrection Corrected = |
| 962 | CorrectTypo(Result.getLookupNameInfo(), Result.getLookupKind(), S, |
| 963 | &SS, *CCC, CTK_ErrorRecovery)) { |
| 964 | unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest; |
| 965 | unsigned QualifiedDiag = diag::err_no_member_suggest; |
| 966 | |
| 967 | NamedDecl *FirstDecl = Corrected.getFoundDecl(); |
| 968 | NamedDecl *UnderlyingFirstDecl = Corrected.getCorrectionDecl(); |
| 969 | if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && |
| 970 | UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) { |
| 971 | UnqualifiedDiag = diag::err_no_template_suggest; |
| 972 | QualifiedDiag = diag::err_no_member_template_suggest; |
| 973 | } else if (UnderlyingFirstDecl && |
| 974 | (isa<TypeDecl>(UnderlyingFirstDecl) || |
| 975 | isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) || |
| 976 | isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) { |
| 977 | UnqualifiedDiag = diag::err_unknown_typename_suggest; |
| 978 | QualifiedDiag = diag::err_unknown_nested_typename_suggest; |
| 979 | } |
| 980 | |
| 981 | if (SS.isEmpty()) { |
| 982 | diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name); |
| 983 | } else {// FIXME: is this even reachable? Test it. |
| 984 | std::string CorrectedStr(Corrected.getAsString(getLangOpts())); |
| 985 | bool DroppedSpecifier = Corrected.WillReplaceSpecifier() && |
| 986 | Name->getName().equals(CorrectedStr); |
| 987 | diagnoseTypo(Corrected, PDiag(QualifiedDiag) |
| 988 | << Name << computeDeclContext(SS, false) |
| 989 | << DroppedSpecifier << SS.getRange()); |
| 990 | } |
| 991 | |
| 992 | // Update the name, so that the caller has the new name. |
| 993 | Name = Corrected.getCorrectionAsIdentifierInfo(); |
| 994 | |
| 995 | // Typo correction corrected to a keyword. |
| 996 | if (Corrected.isKeyword()) |
| 997 | return Name; |
| 998 | |
| 999 | // Also update the LookupResult... |
| 1000 | // FIXME: This should probably go away at some point |
| 1001 | Result.clear(); |
| 1002 | Result.setLookupName(Corrected.getCorrection()); |
| 1003 | if (FirstDecl) |
| 1004 | Result.addDecl(FirstDecl); |
| 1005 | |
| 1006 | // If we found an Objective-C instance variable, let |
| 1007 | // LookupInObjCMethod build the appropriate expression to |
| 1008 | // reference the ivar. |
| 1009 | // FIXME: This is a gross hack. |
| 1010 | if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) { |
| 1011 | DeclResult R = |
| 1012 | LookupIvarInObjCMethod(Result, S, Ivar->getIdentifier()); |
| 1013 | if (R.isInvalid()) |
| 1014 | return NameClassification::Error(); |
| 1015 | if (R.isUsable()) |
| 1016 | return NameClassification::NonType(Ivar); |
| 1017 | } |
| 1018 | |
| 1019 | goto Corrected; |
| 1020 | } |
| 1021 | } |
| 1022 | |
| 1023 | // We failed to correct; just fall through and let the parser deal with it. |
| 1024 | Result.suppressDiagnostics(); |
| 1025 | return NameClassification::Unknown(); |
| 1026 | |
| 1027 | case LookupResult::NotFoundInCurrentInstantiation: { |
| 1028 | // We performed name lookup into the current instantiation, and there were |
| 1029 | // dependent bases, so we treat this result the same way as any other |
| 1030 | // dependent nested-name-specifier. |
| 1031 | |
| 1032 | // C++ [temp.res]p2: |
| 1033 | // A name used in a template declaration or definition and that is |
| 1034 | // dependent on a template-parameter is assumed not to name a type |
| 1035 | // unless the applicable name lookup finds a type name or the name is |
| 1036 | // qualified by the keyword typename. |
| 1037 | // |
| 1038 | // FIXME: If the next token is '<', we might want to ask the parser to |
| 1039 | // perform some heroics to see if we actually have a |
| 1040 | // template-argument-list, which would indicate a missing 'template' |
| 1041 | // keyword here. |
| 1042 | return NameClassification::DependentNonType(); |
| 1043 | } |
| 1044 | |
| 1045 | case LookupResult::Found: |
| 1046 | case LookupResult::FoundOverloaded: |
| 1047 | case LookupResult::FoundUnresolvedValue: |
| 1048 | break; |
| 1049 | |
| 1050 | case LookupResult::Ambiguous: |
| 1051 | if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && |
| 1052 | hasAnyAcceptableTemplateNames(Result, /*AllowFunctionTemplates=*/true, |
| 1053 | /*AllowDependent=*/false)) { |
| 1054 | // C++ [temp.local]p3: |
| 1055 | // A lookup that finds an injected-class-name (10.2) can result in an |
| 1056 | // ambiguity in certain cases (for example, if it is found in more than |
| 1057 | // one base class). If all of the injected-class-names that are found |
| 1058 | // refer to specializations of the same class template, and if the name |
| 1059 | // is followed by a template-argument-list, the reference refers to the |
| 1060 | // class template itself and not a specialization thereof, and is not |
| 1061 | // ambiguous. |
| 1062 | // |
| 1063 | // This filtering can make an ambiguous result into an unambiguous one, |
| 1064 | // so try again after filtering out template names. |
| 1065 | FilterAcceptableTemplateNames(Result); |
| 1066 | if (!Result.isAmbiguous()) { |
| 1067 | IsFilteredTemplateName = true; |
| 1068 | break; |
| 1069 | } |
| 1070 | } |
| 1071 | |
| 1072 | // Diagnose the ambiguity and return an error. |
| 1073 | return NameClassification::Error(); |
| 1074 | } |
| 1075 | |
| 1076 | if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && |
| 1077 | (IsFilteredTemplateName || |
| 1078 | hasAnyAcceptableTemplateNames( |
| 1079 | Result, /*AllowFunctionTemplates=*/true, |
| 1080 | /*AllowDependent=*/false, |
| 1081 | /*AllowNonTemplateFunctions*/ SS.isEmpty() && |
| 1082 | getLangOpts().CPlusPlus20))) { |
| 1083 | // C++ [temp.names]p3: |
| 1084 | // After name lookup (3.4) finds that a name is a template-name or that |
| 1085 | // an operator-function-id or a literal- operator-id refers to a set of |
| 1086 | // overloaded functions any member of which is a function template if |
| 1087 | // this is followed by a <, the < is always taken as the delimiter of a |
| 1088 | // template-argument-list and never as the less-than operator. |
| 1089 | // C++2a [temp.names]p2: |
| 1090 | // A name is also considered to refer to a template if it is an |
| 1091 | // unqualified-id followed by a < and name lookup finds either one |
| 1092 | // or more functions or finds nothing. |
| 1093 | if (!IsFilteredTemplateName) |
| 1094 | FilterAcceptableTemplateNames(Result); |
| 1095 | |
| 1096 | bool IsFunctionTemplate; |
| 1097 | bool IsVarTemplate; |
| 1098 | TemplateName Template; |
| 1099 | if (Result.end() - Result.begin() > 1) { |
| 1100 | IsFunctionTemplate = true; |
| 1101 | Template = Context.getOverloadedTemplateName(Result.begin(), |
| 1102 | Result.end()); |
| 1103 | } else if (!Result.empty()) { |
| 1104 | auto *TD = cast<TemplateDecl>(getAsTemplateNameDecl( |
| 1105 | *Result.begin(), /*AllowFunctionTemplates=*/true, |
| 1106 | /*AllowDependent=*/false)); |
| 1107 | IsFunctionTemplate = isa<FunctionTemplateDecl>(TD); |
| 1108 | IsVarTemplate = isa<VarTemplateDecl>(TD); |
| 1109 | |
| 1110 | if (SS.isNotEmpty()) |
| 1111 | Template = |
| 1112 | Context.getQualifiedTemplateName(SS.getScopeRep(), |
| 1113 | /*TemplateKeyword=*/false, TD); |
| 1114 | else |
| 1115 | Template = TemplateName(TD); |
| 1116 | } else { |
| 1117 | // All results were non-template functions. This is a function template |
| 1118 | // name. |
| 1119 | IsFunctionTemplate = true; |
| 1120 | Template = Context.getAssumedTemplateName(NameInfo.getName()); |
| 1121 | } |
| 1122 | |
| 1123 | if (IsFunctionTemplate) { |
| 1124 | // Function templates always go through overload resolution, at which |
| 1125 | // point we'll perform the various checks (e.g., accessibility) we need |
| 1126 | // to based on which function we selected. |
| 1127 | Result.suppressDiagnostics(); |
| 1128 | |
| 1129 | return NameClassification::FunctionTemplate(Template); |
| 1130 | } |
| 1131 | |
| 1132 | return IsVarTemplate ? NameClassification::VarTemplate(Template) |
| 1133 | : NameClassification::TypeTemplate(Template); |
| 1134 | } |
| 1135 | |
| 1136 | NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl(); |
| 1137 | if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) { |
| 1138 | DiagnoseUseOfDecl(Type, NameLoc); |
| 1139 | MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false); |
| 1140 | QualType T = Context.getTypeDeclType(Type); |
| 1141 | if (SS.isNotEmpty()) |
| 1142 | return buildNestedType(*this, SS, T, NameLoc); |
| 1143 | return ParsedType::make(T); |
| 1144 | } |
| 1145 | |
| 1146 | ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl); |
| 1147 | if (!Class) { |
| 1148 | // FIXME: It's unfortunate that we don't have a Type node for handling this. |
| 1149 | if (ObjCCompatibleAliasDecl *Alias = |
| 1150 | dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl)) |
| 1151 | Class = Alias->getClassInterface(); |
| 1152 | } |
| 1153 | |
| 1154 | if (Class) { |
| 1155 | DiagnoseUseOfDecl(Class, NameLoc); |
| 1156 | |
| 1157 | if (NextToken.is(tok::period)) { |
| 1158 | // Interface. <something> is parsed as a property reference expression. |
| 1159 | // Just return "unknown" as a fall-through for now. |
| 1160 | Result.suppressDiagnostics(); |
| 1161 | return NameClassification::Unknown(); |
| 1162 | } |
| 1163 | |
| 1164 | QualType T = Context.getObjCInterfaceType(Class); |
| 1165 | return ParsedType::make(T); |
| 1166 | } |
| 1167 | |
| 1168 | if (isa<ConceptDecl>(FirstDecl)) |
| 1169 | return NameClassification::Concept( |
| 1170 | TemplateName(cast<TemplateDecl>(FirstDecl))); |
| 1171 | |
| 1172 | if (auto *EmptyD = dyn_cast<UnresolvedUsingIfExistsDecl>(FirstDecl)) { |
| 1173 | (void)DiagnoseUseOfDecl(EmptyD, NameLoc); |
| 1174 | return NameClassification::Error(); |
| 1175 | } |
| 1176 | |
| 1177 | // We can have a type template here if we're classifying a template argument. |
| 1178 | if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl) && |
| 1179 | !isa<VarTemplateDecl>(FirstDecl)) |
| 1180 | return NameClassification::TypeTemplate( |
| 1181 | TemplateName(cast<TemplateDecl>(FirstDecl))); |
| 1182 | |
| 1183 | // Check for a tag type hidden by a non-type decl in a few cases where it |
| 1184 | // seems likely a type is wanted instead of the non-type that was found. |
| 1185 | bool NextIsOp = NextToken.isOneOf(tok::amp, tok::star); |
| 1186 | if ((NextToken.is(tok::identifier) || |
| 1187 | (NextIsOp && |
| 1188 | FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) && |
| 1189 | isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) { |
| 1190 | TypeDecl *Type = Result.getAsSingle<TypeDecl>(); |
| 1191 | DiagnoseUseOfDecl(Type, NameLoc); |
| 1192 | QualType T = Context.getTypeDeclType(Type); |
| 1193 | if (SS.isNotEmpty()) |
| 1194 | return buildNestedType(*this, SS, T, NameLoc); |
| 1195 | return ParsedType::make(T); |
| 1196 | } |
| 1197 | |
| 1198 | // If we already know which single declaration is referenced, just annotate |
| 1199 | // that declaration directly. Defer resolving even non-overloaded class |
| 1200 | // member accesses, as we need to defer certain access checks until we know |
| 1201 | // the context. |
| 1202 | bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren)); |
| 1203 | if (Result.isSingleResult() && !ADL && !FirstDecl->isCXXClassMember()) |
| 1204 | return NameClassification::NonType(Result.getRepresentativeDecl()); |
| 1205 | |
| 1206 | // Otherwise, this is an overload set that we will need to resolve later. |
| 1207 | Result.suppressDiagnostics(); |
| 1208 | return NameClassification::OverloadSet(UnresolvedLookupExpr::Create( |
| 1209 | Context, Result.getNamingClass(), SS.getWithLocInContext(Context), |
| 1210 | Result.getLookupNameInfo(), ADL, Result.isOverloadedResult(), |
| 1211 | Result.begin(), Result.end())); |
| 1212 | } |
| 1213 | |
| 1214 | ExprResult |
| 1215 | Sema::ActOnNameClassifiedAsUndeclaredNonType(IdentifierInfo *Name, |
| 1216 | SourceLocation NameLoc) { |
| 1217 | assert(getLangOpts().CPlusPlus && "ADL-only call in C?")(static_cast<void> (0)); |
| 1218 | CXXScopeSpec SS; |
| 1219 | LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName); |
| 1220 | return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true); |
| 1221 | } |
| 1222 | |
| 1223 | ExprResult |
| 1224 | Sema::ActOnNameClassifiedAsDependentNonType(const CXXScopeSpec &SS, |
| 1225 | IdentifierInfo *Name, |
| 1226 | SourceLocation NameLoc, |
| 1227 | bool IsAddressOfOperand) { |
| 1228 | DeclarationNameInfo NameInfo(Name, NameLoc); |
| 1229 | return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(), |
| 1230 | NameInfo, IsAddressOfOperand, |
| 1231 | /*TemplateArgs=*/nullptr); |
| 1232 | } |
| 1233 | |
| 1234 | ExprResult Sema::ActOnNameClassifiedAsNonType(Scope *S, const CXXScopeSpec &SS, |
| 1235 | NamedDecl *Found, |
| 1236 | SourceLocation NameLoc, |
| 1237 | const Token &NextToken) { |
| 1238 | if (getCurMethodDecl() && SS.isEmpty()) |
| 1239 | if (auto *Ivar = dyn_cast<ObjCIvarDecl>(Found->getUnderlyingDecl())) |
| 1240 | return BuildIvarRefExpr(S, NameLoc, Ivar); |
| 1241 | |
| 1242 | // Reconstruct the lookup result. |
| 1243 | LookupResult Result(*this, Found->getDeclName(), NameLoc, LookupOrdinaryName); |
| 1244 | Result.addDecl(Found); |
| 1245 | Result.resolveKind(); |
| 1246 | |
| 1247 | bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren)); |
| 1248 | return BuildDeclarationNameExpr(SS, Result, ADL); |
| 1249 | } |
| 1250 | |
| 1251 | ExprResult Sema::ActOnNameClassifiedAsOverloadSet(Scope *S, Expr *E) { |
| 1252 | // For an implicit class member access, transform the result into a member |
| 1253 | // access expression if necessary. |
| 1254 | auto *ULE = cast<UnresolvedLookupExpr>(E); |
| 1255 | if ((*ULE->decls_begin())->isCXXClassMember()) { |
| 1256 | CXXScopeSpec SS; |
| 1257 | SS.Adopt(ULE->getQualifierLoc()); |
| 1258 | |
| 1259 | // Reconstruct the lookup result. |
| 1260 | LookupResult Result(*this, ULE->getName(), ULE->getNameLoc(), |
| 1261 | LookupOrdinaryName); |
| 1262 | Result.setNamingClass(ULE->getNamingClass()); |
| 1263 | for (auto I = ULE->decls_begin(), E = ULE->decls_end(); I != E; ++I) |
| 1264 | Result.addDecl(*I, I.getAccess()); |
| 1265 | Result.resolveKind(); |
| 1266 | return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result, |
| 1267 | nullptr, S); |
| 1268 | } |
| 1269 | |
| 1270 | // Otherwise, this is already in the form we needed, and no further checks |
| 1271 | // are necessary. |
| 1272 | return ULE; |
| 1273 | } |
| 1274 | |
| 1275 | Sema::TemplateNameKindForDiagnostics |
| 1276 | Sema::getTemplateNameKindForDiagnostics(TemplateName Name) { |
| 1277 | auto *TD = Name.getAsTemplateDecl(); |
| 1278 | if (!TD) |
| 1279 | return TemplateNameKindForDiagnostics::DependentTemplate; |
| 1280 | if (isa<ClassTemplateDecl>(TD)) |
| 1281 | return TemplateNameKindForDiagnostics::ClassTemplate; |
| 1282 | if (isa<FunctionTemplateDecl>(TD)) |
| 1283 | return TemplateNameKindForDiagnostics::FunctionTemplate; |
| 1284 | if (isa<VarTemplateDecl>(TD)) |
| 1285 | return TemplateNameKindForDiagnostics::VarTemplate; |
| 1286 | if (isa<TypeAliasTemplateDecl>(TD)) |
| 1287 | return TemplateNameKindForDiagnostics::AliasTemplate; |
| 1288 | if (isa<TemplateTemplateParmDecl>(TD)) |
| 1289 | return TemplateNameKindForDiagnostics::TemplateTemplateParam; |
| 1290 | if (isa<ConceptDecl>(TD)) |
| 1291 | return TemplateNameKindForDiagnostics::Concept; |
| 1292 | return TemplateNameKindForDiagnostics::DependentTemplate; |
| 1293 | } |
| 1294 | |
| 1295 | void Sema::PushDeclContext(Scope *S, DeclContext *DC) { |
| 1296 | assert(DC->getLexicalParent() == CurContext &&(static_cast<void> (0)) |
| 1297 | "The next DeclContext should be lexically contained in the current one.")(static_cast<void> (0)); |
| 1298 | CurContext = DC; |
| 1299 | S->setEntity(DC); |
| 1300 | } |
| 1301 | |
| 1302 | void Sema::PopDeclContext() { |
| 1303 | assert(CurContext && "DeclContext imbalance!")(static_cast<void> (0)); |
| 1304 | |
| 1305 | CurContext = CurContext->getLexicalParent(); |
| 1306 | assert(CurContext && "Popped translation unit!")(static_cast<void> (0)); |
| 1307 | } |
| 1308 | |
| 1309 | Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S, |
| 1310 | Decl *D) { |
| 1311 | // Unlike PushDeclContext, the context to which we return is not necessarily |
| 1312 | // the containing DC of TD, because the new context will be some pre-existing |
| 1313 | // TagDecl definition instead of a fresh one. |
| 1314 | auto Result = static_cast<SkippedDefinitionContext>(CurContext); |
| 1315 | CurContext = cast<TagDecl>(D)->getDefinition(); |
| 1316 | assert(CurContext && "skipping definition of undefined tag")(static_cast<void> (0)); |
| 1317 | // Start lookups from the parent of the current context; we don't want to look |
| 1318 | // into the pre-existing complete definition. |
| 1319 | S->setEntity(CurContext->getLookupParent()); |
| 1320 | return Result; |
| 1321 | } |
| 1322 | |
| 1323 | void Sema::ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context) { |
| 1324 | CurContext = static_cast<decltype(CurContext)>(Context); |
| 1325 | } |
| 1326 | |
| 1327 | /// EnterDeclaratorContext - Used when we must lookup names in the context |
| 1328 | /// of a declarator's nested name specifier. |
| 1329 | /// |
| 1330 | void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { |
| 1331 | // C++0x [basic.lookup.unqual]p13: |
| 1332 | // A name used in the definition of a static data member of class |
| 1333 | // X (after the qualified-id of the static member) is looked up as |
| 1334 | // if the name was used in a member function of X. |
| 1335 | // C++0x [basic.lookup.unqual]p14: |
| 1336 | // If a variable member of a namespace is defined outside of the |
| 1337 | // scope of its namespace then any name used in the definition of |
| 1338 | // the variable member (after the declarator-id) is looked up as |
| 1339 | // if the definition of the variable member occurred in its |
| 1340 | // namespace. |
| 1341 | // Both of these imply that we should push a scope whose context |
| 1342 | // is the semantic context of the declaration. We can't use |
| 1343 | // PushDeclContext here because that context is not necessarily |
| 1344 | // lexically contained in the current context. Fortunately, |
| 1345 | // the containing scope should have the appropriate information. |
| 1346 | |
| 1347 | assert(!S->getEntity() && "scope already has entity")(static_cast<void> (0)); |
| 1348 | |
| 1349 | #ifndef NDEBUG1 |
| 1350 | Scope *Ancestor = S->getParent(); |
| 1351 | while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); |
| 1352 | assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch")(static_cast<void> (0)); |
| 1353 | #endif |
| 1354 | |
| 1355 | CurContext = DC; |
| 1356 | S->setEntity(DC); |
| 1357 | |
| 1358 | if (S->getParent()->isTemplateParamScope()) { |
| 1359 | // Also set the corresponding entities for all immediately-enclosing |
| 1360 | // template parameter scopes. |
| 1361 | EnterTemplatedContext(S->getParent(), DC); |
| 1362 | } |
| 1363 | } |
| 1364 | |
| 1365 | void Sema::ExitDeclaratorContext(Scope *S) { |
| 1366 | assert(S->getEntity() == CurContext && "Context imbalance!")(static_cast<void> (0)); |
| 1367 | |
| 1368 | // Switch back to the lexical context. The safety of this is |
| 1369 | // enforced by an assert in EnterDeclaratorContext. |
| 1370 | Scope *Ancestor = S->getParent(); |
| 1371 | while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); |
| 1372 | CurContext = Ancestor->getEntity(); |
| 1373 | |
| 1374 | // We don't need to do anything with the scope, which is going to |
| 1375 | // disappear. |
| 1376 | } |
| 1377 | |
| 1378 | void Sema::EnterTemplatedContext(Scope *S, DeclContext *DC) { |
| 1379 | assert(S->isTemplateParamScope() &&(static_cast<void> (0)) |
| 1380 | "expected to be initializing a template parameter scope")(static_cast<void> (0)); |
| 1381 | |
| 1382 | // C++20 [temp.local]p7: |
| 1383 | // In the definition of a member of a class template that appears outside |
| 1384 | // of the class template definition, the name of a member of the class |
| 1385 | // template hides the name of a template-parameter of any enclosing class |
| 1386 | // templates (but not a template-parameter of the member if the member is a |
| 1387 | // class or function template). |
| 1388 | // C++20 [temp.local]p9: |
| 1389 | // In the definition of a class template or in the definition of a member |
| 1390 | // of such a template that appears outside of the template definition, for |
| 1391 | // each non-dependent base class (13.8.2.1), if the name of the base class |
| 1392 | // or the name of a member of the base class is the same as the name of a |
| 1393 | // template-parameter, the base class name or member name hides the |
| 1394 | // template-parameter name (6.4.10). |
| 1395 | // |
| 1396 | // This means that a template parameter scope should be searched immediately |
| 1397 | // after searching the DeclContext for which it is a template parameter |
| 1398 | // scope. For example, for |
| 1399 | // template<typename T> template<typename U> template<typename V> |
| 1400 | // void N::A<T>::B<U>::f(...) |
| 1401 | // we search V then B<U> (and base classes) then U then A<T> (and base |
| 1402 | // classes) then T then N then ::. |
| 1403 | unsigned ScopeDepth = getTemplateDepth(S); |
| 1404 | for (; S && S->isTemplateParamScope(); S = S->getParent(), --ScopeDepth) { |
| 1405 | DeclContext *SearchDCAfterScope = DC; |
| 1406 | for (; DC; DC = DC->getLookupParent()) { |
| 1407 | if (const TemplateParameterList *TPL = |
| 1408 | cast<Decl>(DC)->getDescribedTemplateParams()) { |
| 1409 | unsigned DCDepth = TPL->getDepth() + 1; |
| 1410 | if (DCDepth > ScopeDepth) |
| 1411 | continue; |
| 1412 | if (ScopeDepth == DCDepth) |
| 1413 | SearchDCAfterScope = DC = DC->getLookupParent(); |
| 1414 | break; |
| 1415 | } |
| 1416 | } |
| 1417 | S->setLookupEntity(SearchDCAfterScope); |
| 1418 | } |
| 1419 | } |
| 1420 | |
| 1421 | void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) { |
| 1422 | // We assume that the caller has already called |
| 1423 | // ActOnReenterTemplateScope so getTemplatedDecl() works. |
| 1424 | FunctionDecl *FD = D->getAsFunction(); |
| 1425 | if (!FD) |
| 1426 | return; |
| 1427 | |
| 1428 | // Same implementation as PushDeclContext, but enters the context |
| 1429 | // from the lexical parent, rather than the top-level class. |
| 1430 | assert(CurContext == FD->getLexicalParent() &&(static_cast<void> (0)) |
| 1431 | "The next DeclContext should be lexically contained in the current one.")(static_cast<void> (0)); |
| 1432 | CurContext = FD; |
| 1433 | S->setEntity(CurContext); |
| 1434 | |
| 1435 | for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) { |
| 1436 | ParmVarDecl *Param = FD->getParamDecl(P); |
| 1437 | // If the parameter has an identifier, then add it to the scope |
| 1438 | if (Param->getIdentifier()) { |
| 1439 | S->AddDecl(Param); |
| 1440 | IdResolver.AddDecl(Param); |
| 1441 | } |
| 1442 | } |
| 1443 | } |
| 1444 | |
| 1445 | void Sema::ActOnExitFunctionContext() { |
| 1446 | // Same implementation as PopDeclContext, but returns to the lexical parent, |
| 1447 | // rather than the top-level class. |
| 1448 | assert(CurContext && "DeclContext imbalance!")(static_cast<void> (0)); |
| 1449 | CurContext = CurContext->getLexicalParent(); |
| 1450 | assert(CurContext && "Popped translation unit!")(static_cast<void> (0)); |
| 1451 | } |
| 1452 | |
| 1453 | /// Determine whether we allow overloading of the function |
| 1454 | /// PrevDecl with another declaration. |
| 1455 | /// |
| 1456 | /// This routine determines whether overloading is possible, not |
| 1457 | /// whether some new function is actually an overload. It will return |
| 1458 | /// true in C++ (where we can always provide overloads) or, as an |
| 1459 | /// extension, in C when the previous function is already an |
| 1460 | /// overloaded function declaration or has the "overloadable" |
| 1461 | /// attribute. |
| 1462 | static bool AllowOverloadingOfFunction(LookupResult &Previous, |
| 1463 | ASTContext &Context, |
| 1464 | const FunctionDecl *New) { |
| 1465 | if (Context.getLangOpts().CPlusPlus) |
| 1466 | return true; |
| 1467 | |
| 1468 | if (Previous.getResultKind() == LookupResult::FoundOverloaded) |
| 1469 | return true; |
| 1470 | |
| 1471 | return Previous.getResultKind() == LookupResult::Found && |
| 1472 | (Previous.getFoundDecl()->hasAttr<OverloadableAttr>() || |
| 1473 | New->hasAttr<OverloadableAttr>()); |
| 1474 | } |
| 1475 | |
| 1476 | /// Add this decl to the scope shadowed decl chains. |
| 1477 | void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { |
| 1478 | // Move up the scope chain until we find the nearest enclosing |
| 1479 | // non-transparent context. The declaration will be introduced into this |
| 1480 | // scope. |
| 1481 | while (S->getEntity() && S->getEntity()->isTransparentContext()) |
| 1482 | S = S->getParent(); |
| 1483 | |
| 1484 | // Add scoped declarations into their context, so that they can be |
| 1485 | // found later. Declarations without a context won't be inserted |
| 1486 | // into any context. |
| 1487 | if (AddToContext) |
| 1488 | CurContext->addDecl(D); |
| 1489 | |
| 1490 | // Out-of-line definitions shouldn't be pushed into scope in C++, unless they |
| 1491 | // are function-local declarations. |
| 1492 | if (getLangOpts().CPlusPlus && D->isOutOfLine() && !S->getFnParent()) |
| 1493 | return; |
| 1494 | |
| 1495 | // Template instantiations should also not be pushed into scope. |
| 1496 | if (isa<FunctionDecl>(D) && |
| 1497 | cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) |
| 1498 | return; |
| 1499 | |
| 1500 | // If this replaces anything in the current scope, |
| 1501 | IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), |
| 1502 | IEnd = IdResolver.end(); |
| 1503 | for (; I != IEnd; ++I) { |
| 1504 | if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { |
| 1505 | S->RemoveDecl(*I); |
| 1506 | IdResolver.RemoveDecl(*I); |
| 1507 | |
| 1508 | // Should only need to replace one decl. |
| 1509 | break; |
| 1510 | } |
| 1511 | } |
| 1512 | |
| 1513 | S->AddDecl(D); |
| 1514 | |
| 1515 | if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { |
| 1516 | // Implicitly-generated labels may end up getting generated in an order that |
| 1517 | // isn't strictly lexical, which breaks name lookup. Be careful to insert |
| 1518 | // the label at the appropriate place in the identifier chain. |
| 1519 | for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { |
| 1520 | DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext(); |
| 1521 | if (IDC == CurContext) { |
| 1522 | if (!S->isDeclScope(*I)) |
| 1523 | continue; |
| 1524 | } else if (IDC->Encloses(CurContext)) |
| 1525 | break; |
| 1526 | } |
| 1527 | |
| 1528 | IdResolver.InsertDeclAfter(I, D); |
| 1529 | } else { |
| 1530 | IdResolver.AddDecl(D); |
| 1531 | } |
| 1532 | warnOnReservedIdentifier(D); |
| 1533 | } |
| 1534 | |
| 1535 | bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S, |
| 1536 | bool AllowInlineNamespace) { |
| 1537 | return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace); |
| 1538 | } |
| 1539 | |
| 1540 | Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { |
| 1541 | DeclContext *TargetDC = DC->getPrimaryContext(); |
| 1542 | do { |
| 1543 | if (DeclContext *ScopeDC = S->getEntity()) |
| 1544 | if (ScopeDC->getPrimaryContext() == TargetDC) |
| 1545 | return S; |
| 1546 | } while ((S = S->getParent())); |
| 1547 | |
| 1548 | return nullptr; |
| 1549 | } |
| 1550 | |
| 1551 | static bool isOutOfScopePreviousDeclaration(NamedDecl *, |
| 1552 | DeclContext*, |
| 1553 | ASTContext&); |
| 1554 | |
| 1555 | /// Filters out lookup results that don't fall within the given scope |
| 1556 | /// as determined by isDeclInScope. |
| 1557 | void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S, |
| 1558 | bool ConsiderLinkage, |
| 1559 | bool AllowInlineNamespace) { |
| 1560 | LookupResult::Filter F = R.makeFilter(); |
| 1561 | while (F.hasNext()) { |
| 1562 | NamedDecl *D = F.next(); |
| 1563 | |
| 1564 | if (isDeclInScope(D, Ctx, S, AllowInlineNamespace)) |
| 1565 | continue; |
| 1566 | |
| 1567 | if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context)) |
| 1568 | continue; |
| 1569 | |
| 1570 | F.erase(); |
| 1571 | } |
| 1572 | |
| 1573 | F.done(); |
| 1574 | } |
| 1575 | |
| 1576 | /// We've determined that \p New is a redeclaration of \p Old. Check that they |
| 1577 | /// have compatible owning modules. |
| 1578 | bool Sema::CheckRedeclarationModuleOwnership(NamedDecl *New, NamedDecl *Old) { |
| 1579 | // FIXME: The Modules TS is not clear about how friend declarations are |
| 1580 | // to be treated. It's not meaningful to have different owning modules for |
| 1581 | // linkage in redeclarations of the same entity, so for now allow the |
| 1582 | // redeclaration and change the owning modules to match. |
| 1583 | if (New->getFriendObjectKind() && |
| 1584 | Old->getOwningModuleForLinkage() != New->getOwningModuleForLinkage()) { |
| 1585 | New->setLocalOwningModule(Old->getOwningModule()); |
| 1586 | makeMergedDefinitionVisible(New); |
| 1587 | return false; |
| 1588 | } |
| 1589 | |
| 1590 | Module *NewM = New->getOwningModule(); |
| 1591 | Module *OldM = Old->getOwningModule(); |
| 1592 | |
| 1593 | if (NewM && NewM->Kind == Module::PrivateModuleFragment) |
| 1594 | NewM = NewM->Parent; |
| 1595 | if (OldM && OldM->Kind == Module::PrivateModuleFragment) |
| 1596 | OldM = OldM->Parent; |
| 1597 | |
| 1598 | if (NewM == OldM) |
| 1599 | return false; |
| 1600 | |
| 1601 | bool NewIsModuleInterface = NewM && NewM->isModulePurview(); |
| 1602 | bool OldIsModuleInterface = OldM && OldM->isModulePurview(); |
| 1603 | if (NewIsModuleInterface || OldIsModuleInterface) { |
| 1604 | // C++ Modules TS [basic.def.odr] 6.2/6.7 [sic]: |
| 1605 | // if a declaration of D [...] appears in the purview of a module, all |
| 1606 | // other such declarations shall appear in the purview of the same module |
| 1607 | Diag(New->getLocation(), diag::err_mismatched_owning_module) |
| 1608 | << New |
| 1609 | << NewIsModuleInterface |
| 1610 | << (NewIsModuleInterface ? NewM->getFullModuleName() : "") |
| 1611 | << OldIsModuleInterface |
| 1612 | << (OldIsModuleInterface ? OldM->getFullModuleName() : ""); |
| 1613 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 1614 | New->setInvalidDecl(); |
| 1615 | return true; |
| 1616 | } |
| 1617 | |
| 1618 | return false; |
| 1619 | } |
| 1620 | |
| 1621 | static bool isUsingDecl(NamedDecl *D) { |
| 1622 | return isa<UsingShadowDecl>(D) || |
| 1623 | isa<UnresolvedUsingTypenameDecl>(D) || |
| 1624 | isa<UnresolvedUsingValueDecl>(D); |
| 1625 | } |
| 1626 | |
| 1627 | /// Removes using shadow declarations from the lookup results. |
| 1628 | static void RemoveUsingDecls(LookupResult &R) { |
| 1629 | LookupResult::Filter F = R.makeFilter(); |
| 1630 | while (F.hasNext()) |
| 1631 | if (isUsingDecl(F.next())) |
| 1632 | F.erase(); |
| 1633 | |
| 1634 | F.done(); |
| 1635 | } |
| 1636 | |
| 1637 | /// Check for this common pattern: |
| 1638 | /// @code |
| 1639 | /// class S { |
| 1640 | /// S(const S&); // DO NOT IMPLEMENT |
| 1641 | /// void operator=(const S&); // DO NOT IMPLEMENT |
| 1642 | /// }; |
| 1643 | /// @endcode |
| 1644 | static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { |
| 1645 | // FIXME: Should check for private access too but access is set after we get |
| 1646 | // the decl here. |
| 1647 | if (D->doesThisDeclarationHaveABody()) |
| 1648 | return false; |
| 1649 | |
| 1650 | if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) |
| 1651 | return CD->isCopyConstructor(); |
| 1652 | return D->isCopyAssignmentOperator(); |
| 1653 | } |
| 1654 | |
| 1655 | // We need this to handle |
| 1656 | // |
| 1657 | // typedef struct { |
| 1658 | // void *foo() { return 0; } |
| 1659 | // } A; |
| 1660 | // |
| 1661 | // When we see foo we don't know if after the typedef we will get 'A' or '*A' |
| 1662 | // for example. If 'A', foo will have external linkage. If we have '*A', |
| 1663 | // foo will have no linkage. Since we can't know until we get to the end |
| 1664 | // of the typedef, this function finds out if D might have non-external linkage. |
| 1665 | // Callers should verify at the end of the TU if it D has external linkage or |
| 1666 | // not. |
| 1667 | bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) { |
| 1668 | const DeclContext *DC = D->getDeclContext(); |
| 1669 | while (!DC->isTranslationUnit()) { |
| 1670 | if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){ |
| 1671 | if (!RD->hasNameForLinkage()) |
| 1672 | return true; |
| 1673 | } |
| 1674 | DC = DC->getParent(); |
| 1675 | } |
| 1676 | |
| 1677 | return !D->isExternallyVisible(); |
| 1678 | } |
| 1679 | |
| 1680 | // FIXME: This needs to be refactored; some other isInMainFile users want |
| 1681 | // these semantics. |
| 1682 | static bool isMainFileLoc(const Sema &S, SourceLocation Loc) { |
| 1683 | if (S.TUKind != TU_Complete) |
| 1684 | return false; |
| 1685 | return S.SourceMgr.isInMainFile(Loc); |
| 1686 | } |
| 1687 | |
| 1688 | bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { |
| 1689 | assert(D)(static_cast<void> (0)); |
| 1690 | |
| 1691 | if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) |
| 1692 | return false; |
| 1693 | |
| 1694 | // Ignore all entities declared within templates, and out-of-line definitions |
| 1695 | // of members of class templates. |
| 1696 | if (D->getDeclContext()->isDependentContext() || |
| 1697 | D->getLexicalDeclContext()->isDependentContext()) |
| 1698 | return false; |
| 1699 | |
| 1700 | if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { |
| 1701 | if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) |
| 1702 | return false; |
| 1703 | // A non-out-of-line declaration of a member specialization was implicitly |
| 1704 | // instantiated; it's the out-of-line declaration that we're interested in. |
| 1705 | if (FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization && |
| 1706 | FD->getMemberSpecializationInfo() && !FD->isOutOfLine()) |
| 1707 | return false; |
| 1708 | |
| 1709 | if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { |
| 1710 | if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) |
| 1711 | return false; |
| 1712 | } else { |
| 1713 | // 'static inline' functions are defined in headers; don't warn. |
| 1714 | if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation())) |
| 1715 | return false; |
| 1716 | } |
| 1717 | |
| 1718 | if (FD->doesThisDeclarationHaveABody() && |
| 1719 | Context.DeclMustBeEmitted(FD)) |
| 1720 | return false; |
| 1721 | } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { |
| 1722 | // Constants and utility variables are defined in headers with internal |
| 1723 | // linkage; don't warn. (Unlike functions, there isn't a convenient marker |
| 1724 | // like "inline".) |
| 1725 | if (!isMainFileLoc(*this, VD->getLocation())) |
| 1726 | return false; |
| 1727 | |
| 1728 | if (Context.DeclMustBeEmitted(VD)) |
| 1729 | return false; |
| 1730 | |
| 1731 | if (VD->isStaticDataMember() && |
| 1732 | VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) |
| 1733 | return false; |
| 1734 | if (VD->isStaticDataMember() && |
| 1735 | VD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization && |
| 1736 | VD->getMemberSpecializationInfo() && !VD->isOutOfLine()) |
| 1737 | return false; |
| 1738 | |
| 1739 | if (VD->isInline() && !isMainFileLoc(*this, VD->getLocation())) |
| 1740 | return false; |
| 1741 | } else { |
| 1742 | return false; |
| 1743 | } |
| 1744 | |
| 1745 | // Only warn for unused decls internal to the translation unit. |
| 1746 | // FIXME: This seems like a bogus check; it suppresses -Wunused-function |
| 1747 | // for inline functions defined in the main source file, for instance. |
| 1748 | return mightHaveNonExternalLinkage(D); |
| 1749 | } |
| 1750 | |
| 1751 | void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { |
| 1752 | if (!D) |
| 1753 | return; |
| 1754 | |
| 1755 | if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { |
| 1756 | const FunctionDecl *First = FD->getFirstDecl(); |
| 1757 | if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) |
| 1758 | return; // First should already be in the vector. |
| 1759 | } |
| 1760 | |
| 1761 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { |
| 1762 | const VarDecl *First = VD->getFirstDecl(); |
| 1763 | if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) |
| 1764 | return; // First should already be in the vector. |
| 1765 | } |
| 1766 | |
| 1767 | if (ShouldWarnIfUnusedFileScopedDecl(D)) |
| 1768 | UnusedFileScopedDecls.push_back(D); |
| 1769 | } |
| 1770 | |
| 1771 | static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { |
| 1772 | if (D->isInvalidDecl()) |
| 1773 | return false; |
| 1774 | |
| 1775 | if (auto *DD = dyn_cast<DecompositionDecl>(D)) { |
| 1776 | // For a decomposition declaration, warn if none of the bindings are |
| 1777 | // referenced, instead of if the variable itself is referenced (which |
| 1778 | // it is, by the bindings' expressions). |
| 1779 | for (auto *BD : DD->bindings()) |
| 1780 | if (BD->isReferenced()) |
| 1781 | return false; |
| 1782 | } else if (!D->getDeclName()) { |
| 1783 | return false; |
| 1784 | } else if (D->isReferenced() || D->isUsed()) { |
| 1785 | return false; |
| 1786 | } |
| 1787 | |
| 1788 | if (D->hasAttr<UnusedAttr>() || D->hasAttr<ObjCPreciseLifetimeAttr>()) |
| 1789 | return false; |
| 1790 | |
| 1791 | if (isa<LabelDecl>(D)) |
| 1792 | return true; |
| 1793 | |
| 1794 | // Except for labels, we only care about unused decls that are local to |
| 1795 | // functions. |
| 1796 | bool WithinFunction = D->getDeclContext()->isFunctionOrMethod(); |
| 1797 | if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext())) |
| 1798 | // For dependent types, the diagnostic is deferred. |
| 1799 | WithinFunction = |
| 1800 | WithinFunction || (R->isLocalClass() && !R->isDependentType()); |
| 1801 | if (!WithinFunction) |
| 1802 | return false; |
| 1803 | |
| 1804 | if (isa<TypedefNameDecl>(D)) |
| 1805 | return true; |
| 1806 | |
| 1807 | // White-list anything that isn't a local variable. |
| 1808 | if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) |
| 1809 | return false; |
| 1810 | |
| 1811 | // Types of valid local variables should be complete, so this should succeed. |
| 1812 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { |
| 1813 | |
| 1814 | // White-list anything with an __attribute__((unused)) type. |
| 1815 | const auto *Ty = VD->getType().getTypePtr(); |
| 1816 | |
| 1817 | // Only look at the outermost level of typedef. |
| 1818 | if (const TypedefType *TT = Ty->getAs<TypedefType>()) { |
| 1819 | if (TT->getDecl()->hasAttr<UnusedAttr>()) |
| 1820 | return false; |
| 1821 | } |
| 1822 | |
| 1823 | // If we failed to complete the type for some reason, or if the type is |
| 1824 | // dependent, don't diagnose the variable. |
| 1825 | if (Ty->isIncompleteType() || Ty->isDependentType()) |
| 1826 | return false; |
| 1827 | |
| 1828 | // Look at the element type to ensure that the warning behaviour is |
| 1829 | // consistent for both scalars and arrays. |
| 1830 | Ty = Ty->getBaseElementTypeUnsafe(); |
| 1831 | |
| 1832 | if (const TagType *TT = Ty->getAs<TagType>()) { |
| 1833 | const TagDecl *Tag = TT->getDecl(); |
| 1834 | if (Tag->hasAttr<UnusedAttr>()) |
| 1835 | return false; |
| 1836 | |
| 1837 | if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { |
| 1838 | if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>()) |
| 1839 | return false; |
| 1840 | |
| 1841 | if (const Expr *Init = VD->getInit()) { |
| 1842 | if (const ExprWithCleanups *Cleanups = |
| 1843 | dyn_cast<ExprWithCleanups>(Init)) |
| 1844 | Init = Cleanups->getSubExpr(); |
| 1845 | const CXXConstructExpr *Construct = |
| 1846 | dyn_cast<CXXConstructExpr>(Init); |
| 1847 | if (Construct && !Construct->isElidable()) { |
| 1848 | CXXConstructorDecl *CD = Construct->getConstructor(); |
| 1849 | if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>() && |
| 1850 | (VD->getInit()->isValueDependent() || !VD->evaluateValue())) |
| 1851 | return false; |
| 1852 | } |
| 1853 | |
| 1854 | // Suppress the warning if we don't know how this is constructed, and |
| 1855 | // it could possibly be non-trivial constructor. |
| 1856 | if (Init->isTypeDependent()) |
| 1857 | for (const CXXConstructorDecl *Ctor : RD->ctors()) |
| 1858 | if (!Ctor->isTrivial()) |
| 1859 | return false; |
| 1860 | } |
| 1861 | } |
| 1862 | } |
| 1863 | |
| 1864 | // TODO: __attribute__((unused)) templates? |
| 1865 | } |
| 1866 | |
| 1867 | return true; |
| 1868 | } |
| 1869 | |
| 1870 | static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx, |
| 1871 | FixItHint &Hint) { |
| 1872 | if (isa<LabelDecl>(D)) { |
| 1873 | SourceLocation AfterColon = Lexer::findLocationAfterToken( |
| 1874 | D->getEndLoc(), tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), |
| 1875 | true); |
| 1876 | if (AfterColon.isInvalid()) |
| 1877 | return; |
| 1878 | Hint = FixItHint::CreateRemoval( |
| 1879 | CharSourceRange::getCharRange(D->getBeginLoc(), AfterColon)); |
| 1880 | } |
| 1881 | } |
| 1882 | |
| 1883 | void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) { |
| 1884 | if (D->getTypeForDecl()->isDependentType()) |
| 1885 | return; |
| 1886 | |
| 1887 | for (auto *TmpD : D->decls()) { |
| 1888 | if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD)) |
| 1889 | DiagnoseUnusedDecl(T); |
| 1890 | else if(const auto *R = dyn_cast<RecordDecl>(TmpD)) |
| 1891 | DiagnoseUnusedNestedTypedefs(R); |
| 1892 | } |
| 1893 | } |
| 1894 | |
| 1895 | /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used |
| 1896 | /// unless they are marked attr(unused). |
| 1897 | void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { |
| 1898 | if (!ShouldDiagnoseUnusedDecl(D)) |
| 1899 | return; |
| 1900 | |
| 1901 | if (auto *TD = dyn_cast<TypedefNameDecl>(D)) { |
| 1902 | // typedefs can be referenced later on, so the diagnostics are emitted |
| 1903 | // at end-of-translation-unit. |
| 1904 | UnusedLocalTypedefNameCandidates.insert(TD); |
| 1905 | return; |
| 1906 | } |
| 1907 | |
| 1908 | FixItHint Hint; |
| 1909 | GenerateFixForUnusedDecl(D, Context, Hint); |
| 1910 | |
| 1911 | unsigned DiagID; |
| 1912 | if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) |
| 1913 | DiagID = diag::warn_unused_exception_param; |
| 1914 | else if (isa<LabelDecl>(D)) |
| 1915 | DiagID = diag::warn_unused_label; |
| 1916 | else |
| 1917 | DiagID = diag::warn_unused_variable; |
| 1918 | |
| 1919 | Diag(D->getLocation(), DiagID) << D << Hint; |
| 1920 | } |
| 1921 | |
| 1922 | void Sema::DiagnoseUnusedButSetDecl(const VarDecl *VD) { |
| 1923 | // If it's not referenced, it can't be set. |
| 1924 | if (!VD->isReferenced() || !VD->getDeclName() || VD->hasAttr<UnusedAttr>()) |
| 1925 | return; |
| 1926 | |
| 1927 | const auto *Ty = VD->getType().getTypePtr()->getBaseElementTypeUnsafe(); |
| 1928 | |
| 1929 | if (Ty->isReferenceType() || Ty->isDependentType()) |
| 1930 | return; |
| 1931 | |
| 1932 | if (const TagType *TT = Ty->getAs<TagType>()) { |
| 1933 | const TagDecl *Tag = TT->getDecl(); |
| 1934 | if (Tag->hasAttr<UnusedAttr>()) |
| 1935 | return; |
| 1936 | // In C++, don't warn for record types that don't have WarnUnusedAttr, to |
| 1937 | // mimic gcc's behavior. |
| 1938 | if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { |
| 1939 | if (!RD->hasAttr<WarnUnusedAttr>()) |
| 1940 | return; |
| 1941 | } |
| 1942 | } |
| 1943 | |
| 1944 | auto iter = RefsMinusAssignments.find(VD); |
| 1945 | if (iter == RefsMinusAssignments.end()) |
| 1946 | return; |
| 1947 | |
| 1948 | assert(iter->getSecond() >= 0 &&(static_cast<void> (0)) |
| 1949 | "Found a negative number of references to a VarDecl")(static_cast<void> (0)); |
| 1950 | if (iter->getSecond() != 0) |
| 1951 | return; |
| 1952 | unsigned DiagID = isa<ParmVarDecl>(VD) ? diag::warn_unused_but_set_parameter |
| 1953 | : diag::warn_unused_but_set_variable; |
| 1954 | Diag(VD->getLocation(), DiagID) << VD; |
| 1955 | } |
| 1956 | |
| 1957 | static void CheckPoppedLabel(LabelDecl *L, Sema &S) { |
| 1958 | // Verify that we have no forward references left. If so, there was a goto |
| 1959 | // or address of a label taken, but no definition of it. Label fwd |
| 1960 | // definitions are indicated with a null substmt which is also not a resolved |
| 1961 | // MS inline assembly label name. |
| 1962 | bool Diagnose = false; |
| 1963 | if (L->isMSAsmLabel()) |
| 1964 | Diagnose = !L->isResolvedMSAsmLabel(); |
| 1965 | else |
| 1966 | Diagnose = L->getStmt() == nullptr; |
| 1967 | if (Diagnose) |
| 1968 | S.Diag(L->getLocation(), diag::err_undeclared_label_use) << L; |
| 1969 | } |
| 1970 | |
| 1971 | void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { |
| 1972 | S->mergeNRVOIntoParent(); |
| 1973 | |
| 1974 | if (S->decl_empty()) return; |
| 1975 | assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&(static_cast<void> (0)) |
| 1976 | "Scope shouldn't contain decls!")(static_cast<void> (0)); |
| 1977 | |
| 1978 | for (auto *TmpD : S->decls()) { |
| 1979 | assert(TmpD && "This decl didn't get pushed??")(static_cast<void> (0)); |
| 1980 | |
| 1981 | assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?")(static_cast<void> (0)); |
| 1982 | NamedDecl *D = cast<NamedDecl>(TmpD); |
| 1983 | |
| 1984 | // Diagnose unused variables in this scope. |
| 1985 | if (!S->hasUnrecoverableErrorOccurred()) { |
| 1986 | DiagnoseUnusedDecl(D); |
| 1987 | if (const auto *RD = dyn_cast<RecordDecl>(D)) |
| 1988 | DiagnoseUnusedNestedTypedefs(RD); |
| 1989 | if (VarDecl *VD = dyn_cast<VarDecl>(D)) { |
| 1990 | DiagnoseUnusedButSetDecl(VD); |
| 1991 | RefsMinusAssignments.erase(VD); |
| 1992 | } |
| 1993 | } |
| 1994 | |
| 1995 | if (!D->getDeclName()) continue; |
| 1996 | |
| 1997 | // If this was a forward reference to a label, verify it was defined. |
| 1998 | if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) |
| 1999 | CheckPoppedLabel(LD, *this); |
| 2000 | |
| 2001 | // Remove this name from our lexical scope, and warn on it if we haven't |
| 2002 | // already. |
| 2003 | IdResolver.RemoveDecl(D); |
| 2004 | auto ShadowI = ShadowingDecls.find(D); |
| 2005 | if (ShadowI != ShadowingDecls.end()) { |
| 2006 | if (const auto *FD = dyn_cast<FieldDecl>(ShadowI->second)) { |
| 2007 | Diag(D->getLocation(), diag::warn_ctor_parm_shadows_field) |
| 2008 | << D << FD << FD->getParent(); |
| 2009 | Diag(FD->getLocation(), diag::note_previous_declaration); |
| 2010 | } |
| 2011 | ShadowingDecls.erase(ShadowI); |
| 2012 | } |
| 2013 | } |
| 2014 | } |
| 2015 | |
| 2016 | /// Look for an Objective-C class in the translation unit. |
| 2017 | /// |
| 2018 | /// \param Id The name of the Objective-C class we're looking for. If |
| 2019 | /// typo-correction fixes this name, the Id will be updated |
| 2020 | /// to the fixed name. |
| 2021 | /// |
| 2022 | /// \param IdLoc The location of the name in the translation unit. |
| 2023 | /// |
| 2024 | /// \param DoTypoCorrection If true, this routine will attempt typo correction |
| 2025 | /// if there is no class with the given name. |
| 2026 | /// |
| 2027 | /// \returns The declaration of the named Objective-C class, or NULL if the |
| 2028 | /// class could not be found. |
| 2029 | ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, |
| 2030 | SourceLocation IdLoc, |
| 2031 | bool DoTypoCorrection) { |
| 2032 | // The third "scope" argument is 0 since we aren't enabling lazy built-in |
| 2033 | // creation from this context. |
| 2034 | NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); |
| 2035 | |
| 2036 | if (!IDecl && DoTypoCorrection) { |
| 2037 | // Perform typo correction at the given location, but only if we |
| 2038 | // find an Objective-C class name. |
| 2039 | DeclFilterCCC<ObjCInterfaceDecl> CCC{}; |
| 2040 | if (TypoCorrection C = |
| 2041 | CorrectTypo(DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, |
| 2042 | TUScope, nullptr, CCC, CTK_ErrorRecovery)) { |
| 2043 | diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id); |
| 2044 | IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>(); |
| 2045 | Id = IDecl->getIdentifier(); |
| 2046 | } |
| 2047 | } |
| 2048 | ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); |
| 2049 | // This routine must always return a class definition, if any. |
| 2050 | if (Def && Def->getDefinition()) |
| 2051 | Def = Def->getDefinition(); |
| 2052 | return Def; |
| 2053 | } |
| 2054 | |
| 2055 | /// getNonFieldDeclScope - Retrieves the innermost scope, starting |
| 2056 | /// from S, where a non-field would be declared. This routine copes |
| 2057 | /// with the difference between C and C++ scoping rules in structs and |
| 2058 | /// unions. For example, the following code is well-formed in C but |
| 2059 | /// ill-formed in C++: |
| 2060 | /// @code |
| 2061 | /// struct S6 { |
| 2062 | /// enum { BAR } e; |
| 2063 | /// }; |
| 2064 | /// |
| 2065 | /// void test_S6() { |
| 2066 | /// struct S6 a; |
| 2067 | /// a.e = BAR; |
| 2068 | /// } |
| 2069 | /// @endcode |
| 2070 | /// For the declaration of BAR, this routine will return a different |
| 2071 | /// scope. The scope S will be the scope of the unnamed enumeration |
| 2072 | /// within S6. In C++, this routine will return the scope associated |
| 2073 | /// with S6, because the enumeration's scope is a transparent |
| 2074 | /// context but structures can contain non-field names. In C, this |
| 2075 | /// routine will return the translation unit scope, since the |
| 2076 | /// enumeration's scope is a transparent context and structures cannot |
| 2077 | /// contain non-field names. |
| 2078 | Scope *Sema::getNonFieldDeclScope(Scope *S) { |
| 2079 | while (((S->getFlags() & Scope::DeclScope) == 0) || |
| 2080 | (S->getEntity() && S->getEntity()->isTransparentContext()) || |
| 2081 | (S->isClassScope() && !getLangOpts().CPlusPlus)) |
| 2082 | S = S->getParent(); |
| 2083 | return S; |
| 2084 | } |
| 2085 | |
| 2086 | static StringRef getHeaderName(Builtin::Context &BuiltinInfo, unsigned ID, |
| 2087 | ASTContext::GetBuiltinTypeError Error) { |
| 2088 | switch (Error) { |
| 2089 | case ASTContext::GE_None: |
| 2090 | return ""; |
| 2091 | case ASTContext::GE_Missing_type: |
| 2092 | return BuiltinInfo.getHeaderName(ID); |
| 2093 | case ASTContext::GE_Missing_stdio: |
| 2094 | return "stdio.h"; |
| 2095 | case ASTContext::GE_Missing_setjmp: |
| 2096 | return "setjmp.h"; |
| 2097 | case ASTContext::GE_Missing_ucontext: |
| 2098 | return "ucontext.h"; |
| 2099 | } |
| 2100 | llvm_unreachable("unhandled error kind")__builtin_unreachable(); |
| 2101 | } |
| 2102 | |
| 2103 | FunctionDecl *Sema::CreateBuiltin(IdentifierInfo *II, QualType Type, |
| 2104 | unsigned ID, SourceLocation Loc) { |
| 2105 | DeclContext *Parent = Context.getTranslationUnitDecl(); |
| 2106 | |
| 2107 | if (getLangOpts().CPlusPlus) { |
| 2108 | LinkageSpecDecl *CLinkageDecl = LinkageSpecDecl::Create( |
| 2109 | Context, Parent, Loc, Loc, LinkageSpecDecl::lang_c, false); |
| 2110 | CLinkageDecl->setImplicit(); |
| 2111 | Parent->addDecl(CLinkageDecl); |
| 2112 | Parent = CLinkageDecl; |
| 2113 | } |
| 2114 | |
| 2115 | FunctionDecl *New = FunctionDecl::Create(Context, Parent, Loc, Loc, II, Type, |
| 2116 | /*TInfo=*/nullptr, SC_Extern, |
| 2117 | getCurFPFeatures().isFPConstrained(), |
| 2118 | false, Type->isFunctionProtoType()); |
| 2119 | New->setImplicit(); |
| 2120 | New->addAttr(BuiltinAttr::CreateImplicit(Context, ID)); |
| 2121 | |
| 2122 | // Create Decl objects for each parameter, adding them to the |
| 2123 | // FunctionDecl. |
| 2124 | if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(Type)) { |
| 2125 | SmallVector<ParmVarDecl *, 16> Params; |
| 2126 | for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) { |
| 2127 | ParmVarDecl *parm = ParmVarDecl::Create( |
| 2128 | Context, New, SourceLocation(), SourceLocation(), nullptr, |
| 2129 | FT->getParamType(i), /*TInfo=*/nullptr, SC_None, nullptr); |
| 2130 | parm->setScopeInfo(0, i); |
| 2131 | Params.push_back(parm); |
| 2132 | } |
| 2133 | New->setParams(Params); |
| 2134 | } |
| 2135 | |
| 2136 | AddKnownFunctionAttributes(New); |
| 2137 | return New; |
| 2138 | } |
| 2139 | |
| 2140 | /// LazilyCreateBuiltin - The specified Builtin-ID was first used at |
| 2141 | /// file scope. lazily create a decl for it. ForRedeclaration is true |
| 2142 | /// if we're creating this built-in in anticipation of redeclaring the |
| 2143 | /// built-in. |
| 2144 | NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID, |
| 2145 | Scope *S, bool ForRedeclaration, |
| 2146 | SourceLocation Loc) { |
| 2147 | LookupNecessaryTypesForBuiltin(S, ID); |
| 2148 | |
| 2149 | ASTContext::GetBuiltinTypeError Error; |
| 2150 | QualType R = Context.GetBuiltinType(ID, Error); |
| 2151 | if (Error) { |
| 2152 | if (!ForRedeclaration) |
| 2153 | return nullptr; |
| 2154 | |
| 2155 | // If we have a builtin without an associated type we should not emit a |
| 2156 | // warning when we were not able to find a type for it. |
| 2157 | if (Error == ASTContext::GE_Missing_type || |
| 2158 | Context.BuiltinInfo.allowTypeMismatch(ID)) |
| 2159 | return nullptr; |
| 2160 | |
| 2161 | // If we could not find a type for setjmp it is because the jmp_buf type was |
| 2162 | // not defined prior to the setjmp declaration. |
| 2163 | if (Error == ASTContext::GE_Missing_setjmp) { |
| 2164 | Diag(Loc, diag::warn_implicit_decl_no_jmp_buf) |
| 2165 | << Context.BuiltinInfo.getName(ID); |
| 2166 | return nullptr; |
| 2167 | } |
| 2168 | |
| 2169 | // Generally, we emit a warning that the declaration requires the |
| 2170 | // appropriate header. |
| 2171 | Diag(Loc, diag::warn_implicit_decl_requires_sysheader) |
| 2172 | << getHeaderName(Context.BuiltinInfo, ID, Error) |
| 2173 | << Context.BuiltinInfo.getName(ID); |
| 2174 | return nullptr; |
| 2175 | } |
| 2176 | |
| 2177 | if (!ForRedeclaration && |
| 2178 | (Context.BuiltinInfo.isPredefinedLibFunction(ID) || |
| 2179 | Context.BuiltinInfo.isHeaderDependentFunction(ID))) { |
| 2180 | Diag(Loc, diag::ext_implicit_lib_function_decl) |
| 2181 | << Context.BuiltinInfo.getName(ID) << R; |
| 2182 | if (const char *Header = Context.BuiltinInfo.getHeaderName(ID)) |
| 2183 | Diag(Loc, diag::note_include_header_or_declare) |
| 2184 | << Header << Context.BuiltinInfo.getName(ID); |
| 2185 | } |
| 2186 | |
| 2187 | if (R.isNull()) |
| 2188 | return nullptr; |
| 2189 | |
| 2190 | FunctionDecl *New = CreateBuiltin(II, R, ID, Loc); |
| 2191 | RegisterLocallyScopedExternCDecl(New, S); |
| 2192 | |
| 2193 | // TUScope is the translation-unit scope to insert this function into. |
| 2194 | // FIXME: This is hideous. We need to teach PushOnScopeChains to |
| 2195 | // relate Scopes to DeclContexts, and probably eliminate CurContext |
| 2196 | // entirely, but we're not there yet. |
| 2197 | DeclContext *SavedContext = CurContext; |
| 2198 | CurContext = New->getDeclContext(); |
| 2199 | PushOnScopeChains(New, TUScope); |
| 2200 | CurContext = SavedContext; |
| 2201 | return New; |
| 2202 | } |
| 2203 | |
| 2204 | /// Typedef declarations don't have linkage, but they still denote the same |
| 2205 | /// entity if their types are the same. |
| 2206 | /// FIXME: This is notionally doing the same thing as ASTReaderDecl's |
| 2207 | /// isSameEntity. |
| 2208 | static void filterNonConflictingPreviousTypedefDecls(Sema &S, |
| 2209 | TypedefNameDecl *Decl, |
| 2210 | LookupResult &Previous) { |
| 2211 | // This is only interesting when modules are enabled. |
| 2212 | if (!S.getLangOpts().Modules && !S.getLangOpts().ModulesLocalVisibility) |
| 2213 | return; |
| 2214 | |
| 2215 | // Empty sets are uninteresting. |
| 2216 | if (Previous.empty()) |
| 2217 | return; |
| 2218 | |
| 2219 | LookupResult::Filter Filter = Previous.makeFilter(); |
| 2220 | while (Filter.hasNext()) { |
| 2221 | NamedDecl *Old = Filter.next(); |
| 2222 | |
| 2223 | // Non-hidden declarations are never ignored. |
| 2224 | if (S.isVisible(Old)) |
| 2225 | continue; |
| 2226 | |
| 2227 | // Declarations of the same entity are not ignored, even if they have |
| 2228 | // different linkages. |
| 2229 | if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) { |
| 2230 | if (S.Context.hasSameType(OldTD->getUnderlyingType(), |
| 2231 | Decl->getUnderlyingType())) |
| 2232 | continue; |
| 2233 | |
| 2234 | // If both declarations give a tag declaration a typedef name for linkage |
| 2235 | // purposes, then they declare the same entity. |
| 2236 | if (OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true) && |
| 2237 | Decl->getAnonDeclWithTypedefName()) |
| 2238 | continue; |
| 2239 | } |
| 2240 | |
| 2241 | Filter.erase(); |
| 2242 | } |
| 2243 | |
| 2244 | Filter.done(); |
| 2245 | } |
| 2246 | |
| 2247 | bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) { |
| 2248 | QualType OldType; |
| 2249 | if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old)) |
| 2250 | OldType = OldTypedef->getUnderlyingType(); |
| 2251 | else |
| 2252 | OldType = Context.getTypeDeclType(Old); |
| 2253 | QualType NewType = New->getUnderlyingType(); |
| 2254 | |
| 2255 | if (NewType->isVariablyModifiedType()) { |
| 2256 | // Must not redefine a typedef with a variably-modified type. |
| 2257 | int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0; |
| 2258 | Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef) |
| 2259 | << Kind << NewType; |
| 2260 | if (Old->getLocation().isValid()) |
| 2261 | notePreviousDefinition(Old, New->getLocation()); |
| 2262 | New->setInvalidDecl(); |
| 2263 | return true; |
| 2264 | } |
| 2265 | |
| 2266 | if (OldType != NewType && |
| 2267 | !OldType->isDependentType() && |
| 2268 | !NewType->isDependentType() && |
| 2269 | !Context.hasSameType(OldType, NewType)) { |
| 2270 | int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0; |
| 2271 | Diag(New->getLocation(), diag::err_redefinition_different_typedef) |
| 2272 | << Kind << NewType << OldType; |
| 2273 | if (Old->getLocation().isValid()) |
| 2274 | notePreviousDefinition(Old, New->getLocation()); |
| 2275 | New->setInvalidDecl(); |
| 2276 | return true; |
| 2277 | } |
| 2278 | return false; |
| 2279 | } |
| 2280 | |
| 2281 | /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the |
| 2282 | /// same name and scope as a previous declaration 'Old'. Figure out |
| 2283 | /// how to resolve this situation, merging decls or emitting |
| 2284 | /// diagnostics as appropriate. If there was an error, set New to be invalid. |
| 2285 | /// |
| 2286 | void Sema::MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New, |
| 2287 | LookupResult &OldDecls) { |
| 2288 | // If the new decl is known invalid already, don't bother doing any |
| 2289 | // merging checks. |
| 2290 | if (New->isInvalidDecl()) return; |
| 2291 | |
| 2292 | // Allow multiple definitions for ObjC built-in typedefs. |
| 2293 | // FIXME: Verify the underlying types are equivalent! |
| 2294 | if (getLangOpts().ObjC) { |
| 2295 | const IdentifierInfo *TypeID = New->getIdentifier(); |
| 2296 | switch (TypeID->getLength()) { |
| 2297 | default: break; |
| 2298 | case 2: |
| 2299 | { |
| 2300 | if (!TypeID->isStr("id")) |
| 2301 | break; |
| 2302 | QualType T = New->getUnderlyingType(); |
| 2303 | if (!T->isPointerType()) |
| 2304 | break; |
| 2305 | if (!T->isVoidPointerType()) { |
| 2306 | QualType PT = T->castAs<PointerType>()->getPointeeType(); |
| 2307 | if (!PT->isStructureType()) |
| 2308 | break; |
| 2309 | } |
| 2310 | Context.setObjCIdRedefinitionType(T); |
| 2311 | // Install the built-in type for 'id', ignoring the current definition. |
| 2312 | New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); |
| 2313 | return; |
| 2314 | } |
| 2315 | case 5: |
| 2316 | if (!TypeID->isStr("Class")) |
| 2317 | break; |
| 2318 | Context.setObjCClassRedefinitionType(New->getUnderlyingType()); |
| 2319 | // Install the built-in type for 'Class', ignoring the current definition. |
| 2320 | New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); |
| 2321 | return; |
| 2322 | case 3: |
| 2323 | if (!TypeID->isStr("SEL")) |
| 2324 | break; |
| 2325 | Context.setObjCSelRedefinitionType(New->getUnderlyingType()); |
| 2326 | // Install the built-in type for 'SEL', ignoring the current definition. |
| 2327 | New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); |
| 2328 | return; |
| 2329 | } |
| 2330 | // Fall through - the typedef name was not a builtin type. |
| 2331 | } |
| 2332 | |
| 2333 | // Verify the old decl was also a type. |
| 2334 | TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); |
| 2335 | if (!Old) { |
| 2336 | Diag(New->getLocation(), diag::err_redefinition_different_kind) |
| 2337 | << New->getDeclName(); |
| 2338 | |
| 2339 | NamedDecl *OldD = OldDecls.getRepresentativeDecl(); |
| 2340 | if (OldD->getLocation().isValid()) |
| 2341 | notePreviousDefinition(OldD, New->getLocation()); |
| 2342 | |
| 2343 | return New->setInvalidDecl(); |
| 2344 | } |
| 2345 | |
| 2346 | // If the old declaration is invalid, just give up here. |
| 2347 | if (Old->isInvalidDecl()) |
| 2348 | return New->setInvalidDecl(); |
| 2349 | |
| 2350 | if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) { |
| 2351 | auto *OldTag = OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true); |
| 2352 | auto *NewTag = New->getAnonDeclWithTypedefName(); |
| 2353 | NamedDecl *Hidden = nullptr; |
| 2354 | if (OldTag && NewTag && |
| 2355 | OldTag->getCanonicalDecl() != NewTag->getCanonicalDecl() && |
| 2356 | !hasVisibleDefinition(OldTag, &Hidden)) { |
| 2357 | // There is a definition of this tag, but it is not visible. Use it |
| 2358 | // instead of our tag. |
| 2359 | New->setTypeForDecl(OldTD->getTypeForDecl()); |
| 2360 | if (OldTD->isModed()) |
| 2361 | New->setModedTypeSourceInfo(OldTD->getTypeSourceInfo(), |
| 2362 | OldTD->getUnderlyingType()); |
| 2363 | else |
| 2364 | New->setTypeSourceInfo(OldTD->getTypeSourceInfo()); |
| 2365 | |
| 2366 | // Make the old tag definition visible. |
| 2367 | makeMergedDefinitionVisible(Hidden); |
| 2368 | |
| 2369 | // If this was an unscoped enumeration, yank all of its enumerators |
| 2370 | // out of the scope. |
| 2371 | if (isa<EnumDecl>(NewTag)) { |
| 2372 | Scope *EnumScope = getNonFieldDeclScope(S); |
| 2373 | for (auto *D : NewTag->decls()) { |
| 2374 | auto *ED = cast<EnumConstantDecl>(D); |
| 2375 | assert(EnumScope->isDeclScope(ED))(static_cast<void> (0)); |
| 2376 | EnumScope->RemoveDecl(ED); |
| 2377 | IdResolver.RemoveDecl(ED); |
| 2378 | ED->getLexicalDeclContext()->removeDecl(ED); |
| 2379 | } |
| 2380 | } |
| 2381 | } |
| 2382 | } |
| 2383 | |
| 2384 | // If the typedef types are not identical, reject them in all languages and |
| 2385 | // with any extensions enabled. |
| 2386 | if (isIncompatibleTypedef(Old, New)) |
| 2387 | return; |
| 2388 | |
| 2389 | // The types match. Link up the redeclaration chain and merge attributes if |
| 2390 | // the old declaration was a typedef. |
| 2391 | if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) { |
| 2392 | New->setPreviousDecl(Typedef); |
| 2393 | mergeDeclAttributes(New, Old); |
| 2394 | } |
| 2395 | |
| 2396 | if (getLangOpts().MicrosoftExt) |
| 2397 | return; |
| 2398 | |
| 2399 | if (getLangOpts().CPlusPlus) { |
| 2400 | // C++ [dcl.typedef]p2: |
| 2401 | // In a given non-class scope, a typedef specifier can be used to |
| 2402 | // redefine the name of any type declared in that scope to refer |
| 2403 | // to the type to which it already refers. |
| 2404 | if (!isa<CXXRecordDecl>(CurContext)) |
| 2405 | return; |
| 2406 | |
| 2407 | // C++0x [dcl.typedef]p4: |
| 2408 | // In a given class scope, a typedef specifier can be used to redefine |
| 2409 | // any class-name declared in that scope that is not also a typedef-name |
| 2410 | // to refer to the type to which it already refers. |
| 2411 | // |
| 2412 | // This wording came in via DR424, which was a correction to the |
| 2413 | // wording in DR56, which accidentally banned code like: |
| 2414 | // |
| 2415 | // struct S { |
| 2416 | // typedef struct A { } A; |
| 2417 | // }; |
| 2418 | // |
| 2419 | // in the C++03 standard. We implement the C++0x semantics, which |
| 2420 | // allow the above but disallow |
| 2421 | // |
| 2422 | // struct S { |
| 2423 | // typedef int I; |
| 2424 | // typedef int I; |
| 2425 | // }; |
| 2426 | // |
| 2427 | // since that was the intent of DR56. |
| 2428 | if (!isa<TypedefNameDecl>(Old)) |
| 2429 | return; |
| 2430 | |
| 2431 | Diag(New->getLocation(), diag::err_redefinition) |
| 2432 | << New->getDeclName(); |
| 2433 | notePreviousDefinition(Old, New->getLocation()); |
| 2434 | return New->setInvalidDecl(); |
| 2435 | } |
| 2436 | |
| 2437 | // Modules always permit redefinition of typedefs, as does C11. |
| 2438 | if (getLangOpts().Modules || getLangOpts().C11) |
| 2439 | return; |
| 2440 | |
| 2441 | // If we have a redefinition of a typedef in C, emit a warning. This warning |
| 2442 | // is normally mapped to an error, but can be controlled with |
| 2443 | // -Wtypedef-redefinition. If either the original or the redefinition is |
| 2444 | // in a system header, don't emit this for compatibility with GCC. |
| 2445 | if (getDiagnostics().getSuppressSystemWarnings() && |
| 2446 | // Some standard types are defined implicitly in Clang (e.g. OpenCL). |
| 2447 | (Old->isImplicit() || |
| 2448 | Context.getSourceManager().isInSystemHeader(Old->getLocation()) || |
| 2449 | Context.getSourceManager().isInSystemHeader(New->getLocation()))) |
| 2450 | return; |
| 2451 | |
| 2452 | Diag(New->getLocation(), diag::ext_redefinition_of_typedef) |
| 2453 | << New->getDeclName(); |
| 2454 | notePreviousDefinition(Old, New->getLocation()); |
| 2455 | } |
| 2456 | |
| 2457 | /// DeclhasAttr - returns true if decl Declaration already has the target |
| 2458 | /// attribute. |
| 2459 | static bool DeclHasAttr(const Decl *D, const Attr *A) { |
| 2460 | const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); |
| 2461 | const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A); |
| 2462 | for (const auto *i : D->attrs()) |
| 2463 | if (i->getKind() == A->getKind()) { |
| 2464 | if (Ann) { |
| 2465 | if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation()) |
| 2466 | return true; |
| 2467 | continue; |
| 2468 | } |
| 2469 | // FIXME: Don't hardcode this check |
| 2470 | if (OA && isa<OwnershipAttr>(i)) |
| 2471 | return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind(); |
| 2472 | return true; |
| 2473 | } |
| 2474 | |
| 2475 | return false; |
| 2476 | } |
| 2477 | |
| 2478 | static bool isAttributeTargetADefinition(Decl *D) { |
| 2479 | if (VarDecl *VD = dyn_cast<VarDecl>(D)) |
| 2480 | return VD->isThisDeclarationADefinition(); |
| 2481 | if (TagDecl *TD = dyn_cast<TagDecl>(D)) |
| 2482 | return TD->isCompleteDefinition() || TD->isBeingDefined(); |
| 2483 | return true; |
| 2484 | } |
| 2485 | |
| 2486 | /// Merge alignment attributes from \p Old to \p New, taking into account the |
| 2487 | /// special semantics of C11's _Alignas specifier and C++11's alignas attribute. |
| 2488 | /// |
| 2489 | /// \return \c true if any attributes were added to \p New. |
| 2490 | static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) { |
| 2491 | // Look for alignas attributes on Old, and pick out whichever attribute |
| 2492 | // specifies the strictest alignment requirement. |
| 2493 | AlignedAttr *OldAlignasAttr = nullptr; |
| 2494 | AlignedAttr *OldStrictestAlignAttr = nullptr; |
| 2495 | unsigned OldAlign = 0; |
| 2496 | for (auto *I : Old->specific_attrs<AlignedAttr>()) { |
| 2497 | // FIXME: We have no way of representing inherited dependent alignments |
| 2498 | // in a case like: |
| 2499 | // template<int A, int B> struct alignas(A) X; |
| 2500 | // template<int A, int B> struct alignas(B) X {}; |
| 2501 | // For now, we just ignore any alignas attributes which are not on the |
| 2502 | // definition in such a case. |
| 2503 | if (I->isAlignmentDependent()) |
| 2504 | return false; |
| 2505 | |
| 2506 | if (I->isAlignas()) |
| 2507 | OldAlignasAttr = I; |
| 2508 | |
| 2509 | unsigned Align = I->getAlignment(S.Context); |
| 2510 | if (Align > OldAlign) { |
| 2511 | OldAlign = Align; |
| 2512 | OldStrictestAlignAttr = I; |
| 2513 | } |
| 2514 | } |
| 2515 | |
| 2516 | // Look for alignas attributes on New. |
| 2517 | AlignedAttr *NewAlignasAttr = nullptr; |
| 2518 | unsigned NewAlign = 0; |
| 2519 | for (auto *I : New->specific_attrs<AlignedAttr>()) { |
| 2520 | if (I->isAlignmentDependent()) |
| 2521 | return false; |
| 2522 | |
| 2523 | if (I->isAlignas()) |
| 2524 | NewAlignasAttr = I; |
| 2525 | |
| 2526 | unsigned Align = I->getAlignment(S.Context); |
| 2527 | if (Align > NewAlign) |
| 2528 | NewAlign = Align; |
| 2529 | } |
| 2530 | |
| 2531 | if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) { |
| 2532 | // Both declarations have 'alignas' attributes. We require them to match. |
| 2533 | // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but |
| 2534 | // fall short. (If two declarations both have alignas, they must both match |
| 2535 | // every definition, and so must match each other if there is a definition.) |
| 2536 | |
| 2537 | // If either declaration only contains 'alignas(0)' specifiers, then it |
| 2538 | // specifies the natural alignment for the type. |
| 2539 | if (OldAlign == 0 || NewAlign == 0) { |
| 2540 | QualType Ty; |
| 2541 | if (ValueDecl *VD = dyn_cast<ValueDecl>(New)) |
| 2542 | Ty = VD->getType(); |
| 2543 | else |
| 2544 | Ty = S.Context.getTagDeclType(cast<TagDecl>(New)); |
| 2545 | |
| 2546 | if (OldAlign == 0) |
| 2547 | OldAlign = S.Context.getTypeAlign(Ty); |
| 2548 | if (NewAlign == 0) |
| 2549 | NewAlign = S.Context.getTypeAlign(Ty); |
| 2550 | } |
| 2551 | |
| 2552 | if (OldAlign != NewAlign) { |
| 2553 | S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch) |
| 2554 | << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity() |
| 2555 | << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity(); |
| 2556 | S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration); |
| 2557 | } |
| 2558 | } |
| 2559 | |
| 2560 | if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) { |
| 2561 | // C++11 [dcl.align]p6: |
| 2562 | // if any declaration of an entity has an alignment-specifier, |
| 2563 | // every defining declaration of that entity shall specify an |
| 2564 | // equivalent alignment. |
| 2565 | // C11 6.7.5/7: |
| 2566 | // If the definition of an object does not have an alignment |
| 2567 | // specifier, any other declaration of that object shall also |
| 2568 | // have no alignment specifier. |
| 2569 | S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition) |
| 2570 | << OldAlignasAttr; |
| 2571 | S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration) |
| 2572 | << OldAlignasAttr; |
| 2573 | } |
| 2574 | |
| 2575 | bool AnyAdded = false; |
| 2576 | |
| 2577 | // Ensure we have an attribute representing the strictest alignment. |
| 2578 | if (OldAlign > NewAlign) { |
| 2579 | AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context); |
| 2580 | Clone->setInherited(true); |
| 2581 | New->addAttr(Clone); |
| 2582 | AnyAdded = true; |
| 2583 | } |
| 2584 | |
| 2585 | // Ensure we have an alignas attribute if the old declaration had one. |
| 2586 | if (OldAlignasAttr && !NewAlignasAttr && |
| 2587 | !(AnyAdded && OldStrictestAlignAttr->isAlignas())) { |
| 2588 | AlignedAttr *Clone = OldAlignasAttr->clone(S.Context); |
| 2589 | Clone->setInherited(true); |
| 2590 | New->addAttr(Clone); |
| 2591 | AnyAdded = true; |
| 2592 | } |
| 2593 | |
| 2594 | return AnyAdded; |
| 2595 | } |
| 2596 | |
| 2597 | #define WANT_DECL_MERGE_LOGIC |
| 2598 | #include "clang/Sema/AttrParsedAttrImpl.inc" |
| 2599 | #undef WANT_DECL_MERGE_LOGIC |
| 2600 | |
| 2601 | static bool mergeDeclAttribute(Sema &S, NamedDecl *D, |
| 2602 | const InheritableAttr *Attr, |
| 2603 | Sema::AvailabilityMergeKind AMK) { |
| 2604 | // Diagnose any mutual exclusions between the attribute that we want to add |
| 2605 | // and attributes that already exist on the declaration. |
| 2606 | if (!DiagnoseMutualExclusions(S, D, Attr)) |
| 2607 | return false; |
| 2608 | |
| 2609 | // This function copies an attribute Attr from a previous declaration to the |
| 2610 | // new declaration D if the new declaration doesn't itself have that attribute |
| 2611 | // yet or if that attribute allows duplicates. |
| 2612 | // If you're adding a new attribute that requires logic different from |
| 2613 | // "use explicit attribute on decl if present, else use attribute from |
| 2614 | // previous decl", for example if the attribute needs to be consistent |
| 2615 | // between redeclarations, you need to call a custom merge function here. |
| 2616 | InheritableAttr *NewAttr = nullptr; |
| 2617 | if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr)) |
| 2618 | NewAttr = S.mergeAvailabilityAttr( |
| 2619 | D, *AA, AA->getPlatform(), AA->isImplicit(), AA->getIntroduced(), |
| 2620 | AA->getDeprecated(), AA->getObsoleted(), AA->getUnavailable(), |
| 2621 | AA->getMessage(), AA->getStrict(), AA->getReplacement(), AMK, |
| 2622 | AA->getPriority()); |
| 2623 | else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr)) |
| 2624 | NewAttr = S.mergeVisibilityAttr(D, *VA, VA->getVisibility()); |
| 2625 | else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr)) |
| 2626 | NewAttr = S.mergeTypeVisibilityAttr(D, *VA, VA->getVisibility()); |
| 2627 | else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr)) |
| 2628 | NewAttr = S.mergeDLLImportAttr(D, *ImportA); |
| 2629 | else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr)) |
| 2630 | NewAttr = S.mergeDLLExportAttr(D, *ExportA); |
| 2631 | else if (const auto *EA = dyn_cast<ErrorAttr>(Attr)) |
| 2632 | NewAttr = S.mergeErrorAttr(D, *EA, EA->getUserDiagnostic()); |
| 2633 | else if (const auto *FA = dyn_cast<FormatAttr>(Attr)) |
| 2634 | NewAttr = S.mergeFormatAttr(D, *FA, FA->getType(), FA->getFormatIdx(), |
| 2635 | FA->getFirstArg()); |
| 2636 | else if (const auto *SA = dyn_cast<SectionAttr>(Attr)) |
| 2637 | NewAttr = S.mergeSectionAttr(D, *SA, SA->getName()); |
| 2638 | else if (const auto *CSA = dyn_cast<CodeSegAttr>(Attr)) |
| 2639 | NewAttr = S.mergeCodeSegAttr(D, *CSA, CSA->getName()); |
| 2640 | else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr)) |
| 2641 | NewAttr = S.mergeMSInheritanceAttr(D, *IA, IA->getBestCase(), |
| 2642 | IA->getInheritanceModel()); |
| 2643 | else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr)) |
| 2644 | NewAttr = S.mergeAlwaysInlineAttr(D, *AA, |
| 2645 | &S.Context.Idents.get(AA->getSpelling())); |
| 2646 | else if (S.getLangOpts().CUDA && isa<FunctionDecl>(D) && |
| 2647 | (isa<CUDAHostAttr>(Attr) || isa<CUDADeviceAttr>(Attr) || |
| 2648 | isa<CUDAGlobalAttr>(Attr))) { |
| 2649 | // CUDA target attributes are part of function signature for |
| 2650 | // overloading purposes and must not be merged. |
| 2651 | return false; |
| 2652 | } else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr)) |
| 2653 | NewAttr = S.mergeMinSizeAttr(D, *MA); |
| 2654 | else if (const auto *SNA = dyn_cast<SwiftNameAttr>(Attr)) |
| 2655 | NewAttr = S.mergeSwiftNameAttr(D, *SNA, SNA->getName()); |
| 2656 | else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr)) |
| 2657 | NewAttr = S.mergeOptimizeNoneAttr(D, *OA); |
| 2658 | else if (const auto *InternalLinkageA = dyn_cast<InternalLinkageAttr>(Attr)) |
| 2659 | NewAttr = S.mergeInternalLinkageAttr(D, *InternalLinkageA); |
| 2660 | else if (isa<AlignedAttr>(Attr)) |
| 2661 | // AlignedAttrs are handled separately, because we need to handle all |
| 2662 | // such attributes on a declaration at the same time. |
| 2663 | NewAttr = nullptr; |
| 2664 | else if ((isa<DeprecatedAttr>(Attr) || isa<UnavailableAttr>(Attr)) && |
| 2665 | (AMK == Sema::AMK_Override || |
| 2666 | AMK == Sema::AMK_ProtocolImplementation || |
| 2667 | AMK == Sema::AMK_OptionalProtocolImplementation)) |
| 2668 | NewAttr = nullptr; |
| 2669 | else if (const auto *UA = dyn_cast<UuidAttr>(Attr)) |
| 2670 | NewAttr = S.mergeUuidAttr(D, *UA, UA->getGuid(), UA->getGuidDecl()); |
| 2671 | else if (const auto *IMA = dyn_cast<WebAssemblyImportModuleAttr>(Attr)) |
| 2672 | NewAttr = S.mergeImportModuleAttr(D, *IMA); |
| 2673 | else if (const auto *INA = dyn_cast<WebAssemblyImportNameAttr>(Attr)) |
| 2674 | NewAttr = S.mergeImportNameAttr(D, *INA); |
| 2675 | else if (const auto *TCBA = dyn_cast<EnforceTCBAttr>(Attr)) |
| 2676 | NewAttr = S.mergeEnforceTCBAttr(D, *TCBA); |
| 2677 | else if (const auto *TCBLA = dyn_cast<EnforceTCBLeafAttr>(Attr)) |
| 2678 | NewAttr = S.mergeEnforceTCBLeafAttr(D, *TCBLA); |
| 2679 | else if (const auto *BTFA = dyn_cast<BTFTagAttr>(Attr)) |
| 2680 | NewAttr = S.mergeBTFTagAttr(D, *BTFA); |
| 2681 | else if (Attr->shouldInheritEvenIfAlreadyPresent() || !DeclHasAttr(D, Attr)) |
| 2682 | NewAttr = cast<InheritableAttr>(Attr->clone(S.Context)); |
| 2683 | |
| 2684 | if (NewAttr) { |
| 2685 | NewAttr->setInherited(true); |
| 2686 | D->addAttr(NewAttr); |
| 2687 | if (isa<MSInheritanceAttr>(NewAttr)) |
| 2688 | S.Consumer.AssignInheritanceModel(cast<CXXRecordDecl>(D)); |
| 2689 | return true; |
| 2690 | } |
| 2691 | |
| 2692 | return false; |
| 2693 | } |
| 2694 | |
| 2695 | static const NamedDecl *getDefinition(const Decl *D) { |
| 2696 | if (const TagDecl *TD = dyn_cast<TagDecl>(D)) |
| 2697 | return TD->getDefinition(); |
| 2698 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { |
| 2699 | const VarDecl *Def = VD->getDefinition(); |
| 2700 | if (Def) |
| 2701 | return Def; |
| 2702 | return VD->getActingDefinition(); |
| 2703 | } |
| 2704 | if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { |
| 2705 | const FunctionDecl *Def = nullptr; |
| 2706 | if (FD->isDefined(Def, true)) |
| 2707 | return Def; |
| 2708 | } |
| 2709 | return nullptr; |
| 2710 | } |
| 2711 | |
| 2712 | static bool hasAttribute(const Decl *D, attr::Kind Kind) { |
| 2713 | for (const auto *Attribute : D->attrs()) |
| 2714 | if (Attribute->getKind() == Kind) |
| 2715 | return true; |
| 2716 | return false; |
| 2717 | } |
| 2718 | |
| 2719 | /// checkNewAttributesAfterDef - If we already have a definition, check that |
| 2720 | /// there are no new attributes in this declaration. |
| 2721 | static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) { |
| 2722 | if (!New->hasAttrs()) |
| 2723 | return; |
| 2724 | |
| 2725 | const NamedDecl *Def = getDefinition(Old); |
| 2726 | if (!Def || Def == New) |
| 2727 | return; |
| 2728 | |
| 2729 | AttrVec &NewAttributes = New->getAttrs(); |
| 2730 | for (unsigned I = 0, E = NewAttributes.size(); I != E;) { |
| 2731 | const Attr *NewAttribute = NewAttributes[I]; |
| 2732 | |
| 2733 | if (isa<AliasAttr>(NewAttribute) || isa<IFuncAttr>(NewAttribute)) { |
| 2734 | if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) { |
| 2735 | Sema::SkipBodyInfo SkipBody; |
| 2736 | S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def), &SkipBody); |
| 2737 | |
| 2738 | // If we're skipping this definition, drop the "alias" attribute. |
| 2739 | if (SkipBody.ShouldSkip) { |
| 2740 | NewAttributes.erase(NewAttributes.begin() + I); |
| 2741 | --E; |
| 2742 | continue; |
| 2743 | } |
| 2744 | } else { |
| 2745 | VarDecl *VD = cast<VarDecl>(New); |
| 2746 | unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() == |
| 2747 | VarDecl::TentativeDefinition |
| 2748 | ? diag::err_alias_after_tentative |
| 2749 | : diag::err_redefinition; |
| 2750 | S.Diag(VD->getLocation(), Diag) << VD->getDeclName(); |
| 2751 | if (Diag == diag::err_redefinition) |
| 2752 | S.notePreviousDefinition(Def, VD->getLocation()); |
| 2753 | else |
| 2754 | S.Diag(Def->getLocation(), diag::note_previous_definition); |
| 2755 | VD->setInvalidDecl(); |
| 2756 | } |
| 2757 | ++I; |
| 2758 | continue; |
| 2759 | } |
| 2760 | |
| 2761 | if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) { |
| 2762 | // Tentative definitions are only interesting for the alias check above. |
| 2763 | if (VD->isThisDeclarationADefinition() != VarDecl::Definition) { |
| 2764 | ++I; |
| 2765 | continue; |
| 2766 | } |
| 2767 | } |
| 2768 | |
| 2769 | if (hasAttribute(Def, NewAttribute->getKind())) { |
| 2770 | ++I; |
| 2771 | continue; // regular attr merging will take care of validating this. |
| 2772 | } |
| 2773 | |
| 2774 | if (isa<C11NoReturnAttr>(NewAttribute)) { |
| 2775 | // C's _Noreturn is allowed to be added to a function after it is defined. |
| 2776 | ++I; |
| 2777 | continue; |
| 2778 | } else if (isa<UuidAttr>(NewAttribute)) { |
| 2779 | // msvc will allow a subsequent definition to add an uuid to a class |
| 2780 | ++I; |
| 2781 | continue; |
| 2782 | } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) { |
| 2783 | if (AA->isAlignas()) { |
| 2784 | // C++11 [dcl.align]p6: |
| 2785 | // if any declaration of an entity has an alignment-specifier, |
| 2786 | // every defining declaration of that entity shall specify an |
| 2787 | // equivalent alignment. |
| 2788 | // C11 6.7.5/7: |
| 2789 | // If the definition of an object does not have an alignment |
| 2790 | // specifier, any other declaration of that object shall also |
| 2791 | // have no alignment specifier. |
| 2792 | S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition) |
| 2793 | << AA; |
| 2794 | S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration) |
| 2795 | << AA; |
| 2796 | NewAttributes.erase(NewAttributes.begin() + I); |
| 2797 | --E; |
| 2798 | continue; |
| 2799 | } |
| 2800 | } else if (isa<LoaderUninitializedAttr>(NewAttribute)) { |
| 2801 | // If there is a C definition followed by a redeclaration with this |
| 2802 | // attribute then there are two different definitions. In C++, prefer the |
| 2803 | // standard diagnostics. |
| 2804 | if (!S.getLangOpts().CPlusPlus) { |
| 2805 | S.Diag(NewAttribute->getLocation(), |
| 2806 | diag::err_loader_uninitialized_redeclaration); |
| 2807 | S.Diag(Def->getLocation(), diag::note_previous_definition); |
| 2808 | NewAttributes.erase(NewAttributes.begin() + I); |
| 2809 | --E; |
| 2810 | continue; |
| 2811 | } |
| 2812 | } else if (isa<SelectAnyAttr>(NewAttribute) && |
| 2813 | cast<VarDecl>(New)->isInline() && |
| 2814 | !cast<VarDecl>(New)->isInlineSpecified()) { |
| 2815 | // Don't warn about applying selectany to implicitly inline variables. |
| 2816 | // Older compilers and language modes would require the use of selectany |
| 2817 | // to make such variables inline, and it would have no effect if we |
| 2818 | // honored it. |
| 2819 | ++I; |
| 2820 | continue; |
| 2821 | } else if (isa<OMPDeclareVariantAttr>(NewAttribute)) { |
| 2822 | // We allow to add OMP[Begin]DeclareVariantAttr to be added to |
| 2823 | // declarations after defintions. |
| 2824 | ++I; |
| 2825 | continue; |
| 2826 | } |
| 2827 | |
| 2828 | S.Diag(NewAttribute->getLocation(), |
| 2829 | diag::warn_attribute_precede_definition); |
| 2830 | S.Diag(Def->getLocation(), diag::note_previous_definition); |
| 2831 | NewAttributes.erase(NewAttributes.begin() + I); |
| 2832 | --E; |
| 2833 | } |
| 2834 | } |
| 2835 | |
| 2836 | static void diagnoseMissingConstinit(Sema &S, const VarDecl *InitDecl, |
| 2837 | const ConstInitAttr *CIAttr, |
| 2838 | bool AttrBeforeInit) { |
| 2839 | SourceLocation InsertLoc = InitDecl->getInnerLocStart(); |
| 2840 | |
| 2841 | // Figure out a good way to write this specifier on the old declaration. |
| 2842 | // FIXME: We should just use the spelling of CIAttr, but we don't preserve |
| 2843 | // enough of the attribute list spelling information to extract that without |
| 2844 | // heroics. |
| 2845 | std::string SuitableSpelling; |
| 2846 | if (S.getLangOpts().CPlusPlus20) |
| 2847 | SuitableSpelling = std::string( |
| 2848 | S.PP.getLastMacroWithSpelling(InsertLoc, {tok::kw_constinit})); |
| 2849 | if (SuitableSpelling.empty() && S.getLangOpts().CPlusPlus11) |
| 2850 | SuitableSpelling = std::string(S.PP.getLastMacroWithSpelling( |
| 2851 | InsertLoc, {tok::l_square, tok::l_square, |
| 2852 | S.PP.getIdentifierInfo("clang"), tok::coloncolon, |
| 2853 | S.PP.getIdentifierInfo("require_constant_initialization"), |
| 2854 | tok::r_square, tok::r_square})); |
| 2855 | if (SuitableSpelling.empty()) |
| 2856 | SuitableSpelling = std::string(S.PP.getLastMacroWithSpelling( |
| 2857 | InsertLoc, {tok::kw___attribute, tok::l_paren, tok::r_paren, |
| 2858 | S.PP.getIdentifierInfo("require_constant_initialization"), |
| 2859 | tok::r_paren, tok::r_paren})); |
| 2860 | if (SuitableSpelling.empty() && S.getLangOpts().CPlusPlus20) |
| 2861 | SuitableSpelling = "constinit"; |
| 2862 | if (SuitableSpelling.empty() && S.getLangOpts().CPlusPlus11) |
| 2863 | SuitableSpelling = "[[clang::require_constant_initialization]]"; |
| 2864 | if (SuitableSpelling.empty()) |
| 2865 | SuitableSpelling = "__attribute__((require_constant_initialization))"; |
| 2866 | SuitableSpelling += " "; |
| 2867 | |
| 2868 | if (AttrBeforeInit) { |
| 2869 | // extern constinit int a; |
| 2870 | // int a = 0; // error (missing 'constinit'), accepted as extension |
| 2871 | assert(CIAttr->isConstinit() && "should not diagnose this for attribute")(static_cast<void> (0)); |
| 2872 | S.Diag(InitDecl->getLocation(), diag::ext_constinit_missing) |
| 2873 | << InitDecl << FixItHint::CreateInsertion(InsertLoc, SuitableSpelling); |
| 2874 | S.Diag(CIAttr->getLocation(), diag::note_constinit_specified_here); |
| 2875 | } else { |
| 2876 | // int a = 0; |
| 2877 | // constinit extern int a; // error (missing 'constinit') |
| 2878 | S.Diag(CIAttr->getLocation(), |
| 2879 | CIAttr->isConstinit() ? diag::err_constinit_added_too_late |
| 2880 | : diag::warn_require_const_init_added_too_late) |
| 2881 | << FixItHint::CreateRemoval(SourceRange(CIAttr->getLocation())); |
| 2882 | S.Diag(InitDecl->getLocation(), diag::note_constinit_missing_here) |
| 2883 | << CIAttr->isConstinit() |
| 2884 | << FixItHint::CreateInsertion(InsertLoc, SuitableSpelling); |
| 2885 | } |
| 2886 | } |
| 2887 | |
| 2888 | /// mergeDeclAttributes - Copy attributes from the Old decl to the New one. |
| 2889 | void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old, |
| 2890 | AvailabilityMergeKind AMK) { |
| 2891 | if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) { |
| 2892 | UsedAttr *NewAttr = OldAttr->clone(Context); |
| 2893 | NewAttr->setInherited(true); |
| 2894 | New->addAttr(NewAttr); |
| 2895 | } |
| 2896 | if (RetainAttr *OldAttr = Old->getMostRecentDecl()->getAttr<RetainAttr>()) { |
| 2897 | RetainAttr *NewAttr = OldAttr->clone(Context); |
| 2898 | NewAttr->setInherited(true); |
| 2899 | New->addAttr(NewAttr); |
| 2900 | } |
| 2901 | |
| 2902 | if (!Old->hasAttrs() && !New->hasAttrs()) |
| 2903 | return; |
| 2904 | |
| 2905 | // [dcl.constinit]p1: |
| 2906 | // If the [constinit] specifier is applied to any declaration of a |
| 2907 | // variable, it shall be applied to the initializing declaration. |
| 2908 | const auto *OldConstInit = Old->getAttr<ConstInitAttr>(); |
| 2909 | const auto *NewConstInit = New->getAttr<ConstInitAttr>(); |
| 2910 | if (bool(OldConstInit) != bool(NewConstInit)) { |
| 2911 | const auto *OldVD = cast<VarDecl>(Old); |
| 2912 | auto *NewVD = cast<VarDecl>(New); |
| 2913 | |
| 2914 | // Find the initializing declaration. Note that we might not have linked |
| 2915 | // the new declaration into the redeclaration chain yet. |
| 2916 | const VarDecl *InitDecl = OldVD->getInitializingDeclaration(); |
| 2917 | if (!InitDecl && |
| 2918 | (NewVD->hasInit() || NewVD->isThisDeclarationADefinition())) |
| 2919 | InitDecl = NewVD; |
| 2920 | |
| 2921 | if (InitDecl == NewVD) { |
| 2922 | // This is the initializing declaration. If it would inherit 'constinit', |
| 2923 | // that's ill-formed. (Note that we do not apply this to the attribute |
| 2924 | // form). |
| 2925 | if (OldConstInit && OldConstInit->isConstinit()) |
| 2926 | diagnoseMissingConstinit(*this, NewVD, OldConstInit, |
| 2927 | /*AttrBeforeInit=*/true); |
| 2928 | } else if (NewConstInit) { |
| 2929 | // This is the first time we've been told that this declaration should |
| 2930 | // have a constant initializer. If we already saw the initializing |
| 2931 | // declaration, this is too late. |
| 2932 | if (InitDecl && InitDecl != NewVD) { |
| 2933 | diagnoseMissingConstinit(*this, InitDecl, NewConstInit, |
| 2934 | /*AttrBeforeInit=*/false); |
| 2935 | NewVD->dropAttr<ConstInitAttr>(); |
| 2936 | } |
| 2937 | } |
| 2938 | } |
| 2939 | |
| 2940 | // Attributes declared post-definition are currently ignored. |
| 2941 | checkNewAttributesAfterDef(*this, New, Old); |
| 2942 | |
| 2943 | if (AsmLabelAttr *NewA = New->getAttr<AsmLabelAttr>()) { |
| 2944 | if (AsmLabelAttr *OldA = Old->getAttr<AsmLabelAttr>()) { |
| 2945 | if (!OldA->isEquivalent(NewA)) { |
| 2946 | // This redeclaration changes __asm__ label. |
| 2947 | Diag(New->getLocation(), diag::err_different_asm_label); |
| 2948 | Diag(OldA->getLocation(), diag::note_previous_declaration); |
| 2949 | } |
| 2950 | } else if (Old->isUsed()) { |
| 2951 | // This redeclaration adds an __asm__ label to a declaration that has |
| 2952 | // already been ODR-used. |
| 2953 | Diag(New->getLocation(), diag::err_late_asm_label_name) |
| 2954 | << isa<FunctionDecl>(Old) << New->getAttr<AsmLabelAttr>()->getRange(); |
| 2955 | } |
| 2956 | } |
| 2957 | |
| 2958 | // Re-declaration cannot add abi_tag's. |
| 2959 | if (const auto *NewAbiTagAttr = New->getAttr<AbiTagAttr>()) { |
| 2960 | if (const auto *OldAbiTagAttr = Old->getAttr<AbiTagAttr>()) { |
| 2961 | for (const auto &NewTag : NewAbiTagAttr->tags()) { |
| 2962 | if (std::find(OldAbiTagAttr->tags_begin(), OldAbiTagAttr->tags_end(), |
| 2963 | NewTag) == OldAbiTagAttr->tags_end()) { |
| 2964 | Diag(NewAbiTagAttr->getLocation(), |
| 2965 | diag::err_new_abi_tag_on_redeclaration) |
| 2966 | << NewTag; |
| 2967 | Diag(OldAbiTagAttr->getLocation(), diag::note_previous_declaration); |
| 2968 | } |
| 2969 | } |
| 2970 | } else { |
| 2971 | Diag(NewAbiTagAttr->getLocation(), diag::err_abi_tag_on_redeclaration); |
| 2972 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 2973 | } |
| 2974 | } |
| 2975 | |
| 2976 | // This redeclaration adds a section attribute. |
| 2977 | if (New->hasAttr<SectionAttr>() && !Old->hasAttr<SectionAttr>()) { |
| 2978 | if (auto *VD = dyn_cast<VarDecl>(New)) { |
| 2979 | if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly) { |
| 2980 | Diag(New->getLocation(), diag::warn_attribute_section_on_redeclaration); |
| 2981 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 2982 | } |
| 2983 | } |
| 2984 | } |
| 2985 | |
| 2986 | // Redeclaration adds code-seg attribute. |
| 2987 | const auto *NewCSA = New->getAttr<CodeSegAttr>(); |
| 2988 | if (NewCSA && !Old->hasAttr<CodeSegAttr>() && |
| 2989 | !NewCSA->isImplicit() && isa<CXXMethodDecl>(New)) { |
| 2990 | Diag(New->getLocation(), diag::warn_mismatched_section) |
| 2991 | << 0 /*codeseg*/; |
| 2992 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 2993 | } |
| 2994 | |
| 2995 | if (!Old->hasAttrs()) |
| 2996 | return; |
| 2997 | |
| 2998 | bool foundAny = New->hasAttrs(); |
| 2999 | |
| 3000 | // Ensure that any moving of objects within the allocated map is done before |
| 3001 | // we process them. |
| 3002 | if (!foundAny) New->setAttrs(AttrVec()); |
| 3003 | |
| 3004 | for (auto *I : Old->specific_attrs<InheritableAttr>()) { |
| 3005 | // Ignore deprecated/unavailable/availability attributes if requested. |
| 3006 | AvailabilityMergeKind LocalAMK = AMK_None; |
| 3007 | if (isa<DeprecatedAttr>(I) || |
| 3008 | isa<UnavailableAttr>(I) || |
| 3009 | isa<AvailabilityAttr>(I)) { |
| 3010 | switch (AMK) { |
| 3011 | case AMK_None: |
| 3012 | continue; |
| 3013 | |
| 3014 | case AMK_Redeclaration: |
| 3015 | case AMK_Override: |
| 3016 | case AMK_ProtocolImplementation: |
| 3017 | case AMK_OptionalProtocolImplementation: |
| 3018 | LocalAMK = AMK; |
| 3019 | break; |
| 3020 | } |
| 3021 | } |
| 3022 | |
| 3023 | // Already handled. |
| 3024 | if (isa<UsedAttr>(I) || isa<RetainAttr>(I)) |
| 3025 | continue; |
| 3026 | |
| 3027 | if (mergeDeclAttribute(*this, New, I, LocalAMK)) |
| 3028 | foundAny = true; |
| 3029 | } |
| 3030 | |
| 3031 | if (mergeAlignedAttrs(*this, New, Old)) |
| 3032 | foundAny = true; |
| 3033 | |
| 3034 | if (!foundAny) New->dropAttrs(); |
| 3035 | } |
| 3036 | |
| 3037 | /// mergeParamDeclAttributes - Copy attributes from the old parameter |
| 3038 | /// to the new one. |
| 3039 | static void mergeParamDeclAttributes(ParmVarDecl *newDecl, |
| 3040 | const ParmVarDecl *oldDecl, |
| 3041 | Sema &S) { |
| 3042 | // C++11 [dcl.attr.depend]p2: |
| 3043 | // The first declaration of a function shall specify the |
| 3044 | // carries_dependency attribute for its declarator-id if any declaration |
| 3045 | // of the function specifies the carries_dependency attribute. |
| 3046 | const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>(); |
| 3047 | if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) { |
| 3048 | S.Diag(CDA->getLocation(), |
| 3049 | diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/; |
| 3050 | // Find the first declaration of the parameter. |
| 3051 | // FIXME: Should we build redeclaration chains for function parameters? |
| 3052 | const FunctionDecl *FirstFD = |
| 3053 | cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl(); |
| 3054 | const ParmVarDecl *FirstVD = |
| 3055 | FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex()); |
| 3056 | S.Diag(FirstVD->getLocation(), |
| 3057 | diag::note_carries_dependency_missing_first_decl) << 1/*Param*/; |
| 3058 | } |
| 3059 | |
| 3060 | if (!oldDecl->hasAttrs()) |
| 3061 | return; |
| 3062 | |
| 3063 | bool foundAny = newDecl->hasAttrs(); |
| 3064 | |
| 3065 | // Ensure that any moving of objects within the allocated map is |
| 3066 | // done before we process them. |
| 3067 | if (!foundAny) newDecl->setAttrs(AttrVec()); |
| 3068 | |
| 3069 | for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) { |
| 3070 | if (!DeclHasAttr(newDecl, I)) { |
| 3071 | InheritableAttr *newAttr = |
| 3072 | cast<InheritableParamAttr>(I->clone(S.Context)); |
| 3073 | newAttr->setInherited(true); |
| 3074 | newDecl->addAttr(newAttr); |
| 3075 | foundAny = true; |
| 3076 | } |
| 3077 | } |
| 3078 | |
| 3079 | if (!foundAny) newDecl->dropAttrs(); |
| 3080 | } |
| 3081 | |
| 3082 | static void mergeParamDeclTypes(ParmVarDecl *NewParam, |
| 3083 | const ParmVarDecl *OldParam, |
| 3084 | Sema &S) { |
| 3085 | if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) { |
| 3086 | if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) { |
| 3087 | if (*Oldnullability != *Newnullability) { |
| 3088 | S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr) |
| 3089 | << DiagNullabilityKind( |
| 3090 | *Newnullability, |
| 3091 | ((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) |
| 3092 | != 0)) |
| 3093 | << DiagNullabilityKind( |
| 3094 | *Oldnullability, |
| 3095 | ((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) |
| 3096 | != 0)); |
| 3097 | S.Diag(OldParam->getLocation(), diag::note_previous_declaration); |
| 3098 | } |
| 3099 | } else { |
| 3100 | QualType NewT = NewParam->getType(); |
| 3101 | NewT = S.Context.getAttributedType( |
| 3102 | AttributedType::getNullabilityAttrKind(*Oldnullability), |
| 3103 | NewT, NewT); |
| 3104 | NewParam->setType(NewT); |
| 3105 | } |
| 3106 | } |
| 3107 | } |
| 3108 | |
| 3109 | namespace { |
| 3110 | |
| 3111 | /// Used in MergeFunctionDecl to keep track of function parameters in |
| 3112 | /// C. |
| 3113 | struct GNUCompatibleParamWarning { |
| 3114 | ParmVarDecl *OldParm; |
| 3115 | ParmVarDecl *NewParm; |
| 3116 | QualType PromotedType; |
| 3117 | }; |
| 3118 | |
| 3119 | } // end anonymous namespace |
| 3120 | |
| 3121 | // Determine whether the previous declaration was a definition, implicit |
| 3122 | // declaration, or a declaration. |
| 3123 | template <typename T> |
| 3124 | static std::pair<diag::kind, SourceLocation> |
| 3125 | getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) { |
| 3126 | diag::kind PrevDiag; |
| 3127 | SourceLocation OldLocation = Old->getLocation(); |
| 3128 | if (Old->isThisDeclarationADefinition()) |
| 3129 | PrevDiag = diag::note_previous_definition; |
| 3130 | else if (Old->isImplicit()) { |
| 3131 | PrevDiag = diag::note_previous_implicit_declaration; |
| 3132 | if (OldLocation.isInvalid()) |
| 3133 | OldLocation = New->getLocation(); |
| 3134 | } else |
| 3135 | PrevDiag = diag::note_previous_declaration; |
| 3136 | return std::make_pair(PrevDiag, OldLocation); |
| 3137 | } |
| 3138 | |
| 3139 | /// canRedefineFunction - checks if a function can be redefined. Currently, |
| 3140 | /// only extern inline functions can be redefined, and even then only in |
| 3141 | /// GNU89 mode. |
| 3142 | static bool canRedefineFunction(const FunctionDecl *FD, |
| 3143 | const LangOptions& LangOpts) { |
| 3144 | return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) && |
| 3145 | !LangOpts.CPlusPlus && |
| 3146 | FD->isInlineSpecified() && |
| 3147 | FD->getStorageClass() == SC_Extern); |
| 3148 | } |
| 3149 | |
| 3150 | const AttributedType *Sema::getCallingConvAttributedType(QualType T) const { |
| 3151 | const AttributedType *AT = T->getAs<AttributedType>(); |
| 3152 | while (AT && !AT->isCallingConv()) |
| 3153 | AT = AT->getModifiedType()->getAs<AttributedType>(); |
| 3154 | return AT; |
| 3155 | } |
| 3156 | |
| 3157 | template <typename T> |
| 3158 | static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) { |
| 3159 | const DeclContext *DC = Old->getDeclContext(); |
| 3160 | if (DC->isRecord()) |
| 3161 | return false; |
| 3162 | |
| 3163 | LanguageLinkage OldLinkage = Old->getLanguageLinkage(); |
| 3164 | if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext()) |
| 3165 | return true; |
| 3166 | if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext()) |
| 3167 | return true; |
| 3168 | return false; |
| 3169 | } |
| 3170 | |
| 3171 | template<typename T> static bool isExternC(T *D) { return D->isExternC(); } |
| 3172 | static bool isExternC(VarTemplateDecl *) { return false; } |
| 3173 | static bool isExternC(FunctionTemplateDecl *) { return false; } |
| 3174 | |
| 3175 | /// Check whether a redeclaration of an entity introduced by a |
| 3176 | /// using-declaration is valid, given that we know it's not an overload |
| 3177 | /// (nor a hidden tag declaration). |
| 3178 | template<typename ExpectedDecl> |
| 3179 | static bool checkUsingShadowRedecl(Sema &S, UsingShadowDecl *OldS, |
| 3180 | ExpectedDecl *New) { |
| 3181 | // C++11 [basic.scope.declarative]p4: |
| 3182 | // Given a set of declarations in a single declarative region, each of |
| 3183 | // which specifies the same unqualified name, |
| 3184 | // -- they shall all refer to the same entity, or all refer to functions |
| 3185 | // and function templates; or |
| 3186 | // -- exactly one declaration shall declare a class name or enumeration |
| 3187 | // name that is not a typedef name and the other declarations shall all |
| 3188 | // refer to the same variable or enumerator, or all refer to functions |
| 3189 | // and function templates; in this case the class name or enumeration |
| 3190 | // name is hidden (3.3.10). |
| 3191 | |
| 3192 | // C++11 [namespace.udecl]p14: |
| 3193 | // If a function declaration in namespace scope or block scope has the |
| 3194 | // same name and the same parameter-type-list as a function introduced |
| 3195 | // by a using-declaration, and the declarations do not declare the same |
| 3196 | // function, the program is ill-formed. |
| 3197 | |
| 3198 | auto *Old = dyn_cast<ExpectedDecl>(OldS->getTargetDecl()); |
| 3199 | if (Old && |
| 3200 | !Old->getDeclContext()->getRedeclContext()->Equals( |
| 3201 | New->getDeclContext()->getRedeclContext()) && |
| 3202 | !(isExternC(Old) && isExternC(New))) |
| 3203 | Old = nullptr; |
| 3204 | |
| 3205 | if (!Old) { |
| 3206 | S.Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); |
| 3207 | S.Diag(OldS->getTargetDecl()->getLocation(), diag::note_using_decl_target); |
| 3208 | S.Diag(OldS->getIntroducer()->getLocation(), diag::note_using_decl) << 0; |
| 3209 | return true; |
| 3210 | } |
| 3211 | return false; |
| 3212 | } |
| 3213 | |
| 3214 | static bool hasIdenticalPassObjectSizeAttrs(const FunctionDecl *A, |
| 3215 | const FunctionDecl *B) { |
| 3216 | assert(A->getNumParams() == B->getNumParams())(static_cast<void> (0)); |
| 3217 | |
| 3218 | auto AttrEq = [](const ParmVarDecl *A, const ParmVarDecl *B) { |
| 3219 | const auto *AttrA = A->getAttr<PassObjectSizeAttr>(); |
| 3220 | const auto *AttrB = B->getAttr<PassObjectSizeAttr>(); |
| 3221 | if (AttrA == AttrB) |
| 3222 | return true; |
| 3223 | return AttrA && AttrB && AttrA->getType() == AttrB->getType() && |
| 3224 | AttrA->isDynamic() == AttrB->isDynamic(); |
| 3225 | }; |
| 3226 | |
| 3227 | return std::equal(A->param_begin(), A->param_end(), B->param_begin(), AttrEq); |
| 3228 | } |
| 3229 | |
| 3230 | /// If necessary, adjust the semantic declaration context for a qualified |
| 3231 | /// declaration to name the correct inline namespace within the qualifier. |
| 3232 | static void adjustDeclContextForDeclaratorDecl(DeclaratorDecl *NewD, |
| 3233 | DeclaratorDecl *OldD) { |
| 3234 | // The only case where we need to update the DeclContext is when |
| 3235 | // redeclaration lookup for a qualified name finds a declaration |
| 3236 | // in an inline namespace within the context named by the qualifier: |
| 3237 | // |
| 3238 | // inline namespace N { int f(); } |
| 3239 | // int ::f(); // Sema DC needs adjusting from :: to N::. |
| 3240 | // |
| 3241 | // For unqualified declarations, the semantic context *can* change |
| 3242 | // along the redeclaration chain (for local extern declarations, |
| 3243 | // extern "C" declarations, and friend declarations in particular). |
| 3244 | if (!NewD->getQualifier()) |
| 3245 | return; |
| 3246 | |
| 3247 | // NewD is probably already in the right context. |
| 3248 | auto *NamedDC = NewD->getDeclContext()->getRedeclContext(); |
| 3249 | auto *SemaDC = OldD->getDeclContext()->getRedeclContext(); |
| 3250 | if (NamedDC->Equals(SemaDC)) |
| 3251 | return; |
| 3252 | |
| 3253 | assert((NamedDC->InEnclosingNamespaceSetOf(SemaDC) ||(static_cast<void> (0)) |
| 3254 | NewD->isInvalidDecl() || OldD->isInvalidDecl()) &&(static_cast<void> (0)) |
| 3255 | "unexpected context for redeclaration")(static_cast<void> (0)); |
| 3256 | |
| 3257 | auto *LexDC = NewD->getLexicalDeclContext(); |
| 3258 | auto FixSemaDC = [=](NamedDecl *D) { |
| 3259 | if (!D) |
| 3260 | return; |
| 3261 | D->setDeclContext(SemaDC); |
| 3262 | D->setLexicalDeclContext(LexDC); |
| 3263 | }; |
| 3264 | |
| 3265 | FixSemaDC(NewD); |
| 3266 | if (auto *FD = dyn_cast<FunctionDecl>(NewD)) |
| 3267 | FixSemaDC(FD->getDescribedFunctionTemplate()); |
| 3268 | else if (auto *VD = dyn_cast<VarDecl>(NewD)) |
| 3269 | FixSemaDC(VD->getDescribedVarTemplate()); |
| 3270 | } |
| 3271 | |
| 3272 | /// MergeFunctionDecl - We just parsed a function 'New' from |
| 3273 | /// declarator D which has the same name and scope as a previous |
| 3274 | /// declaration 'Old'. Figure out how to resolve this situation, |
| 3275 | /// merging decls or emitting diagnostics as appropriate. |
| 3276 | /// |
| 3277 | /// In C++, New and Old must be declarations that are not |
| 3278 | /// overloaded. Use IsOverload to determine whether New and Old are |
| 3279 | /// overloaded, and to select the Old declaration that New should be |
| 3280 | /// merged with. |
| 3281 | /// |
| 3282 | /// Returns true if there was an error, false otherwise. |
| 3283 | bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD, |
| 3284 | Scope *S, bool MergeTypeWithOld) { |
| 3285 | // Verify the old decl was also a function. |
| 3286 | FunctionDecl *Old = OldD->getAsFunction(); |
| 3287 | if (!Old) { |
| 3288 | if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { |
| 3289 | if (New->getFriendObjectKind()) { |
| 3290 | Diag(New->getLocation(), diag::err_using_decl_friend); |
| 3291 | Diag(Shadow->getTargetDecl()->getLocation(), |
| 3292 | diag::note_using_decl_target); |
| 3293 | Diag(Shadow->getIntroducer()->getLocation(), diag::note_using_decl) |
| 3294 | << 0; |
| 3295 | return true; |
| 3296 | } |
| 3297 | |
| 3298 | // Check whether the two declarations might declare the same function or |
| 3299 | // function template. |
| 3300 | if (FunctionTemplateDecl *NewTemplate = |
| 3301 | New->getDescribedFunctionTemplate()) { |
| 3302 | if (checkUsingShadowRedecl<FunctionTemplateDecl>(*this, Shadow, |
| 3303 | NewTemplate)) |
| 3304 | return true; |
| 3305 | OldD = Old = cast<FunctionTemplateDecl>(Shadow->getTargetDecl()) |
| 3306 | ->getAsFunction(); |
| 3307 | } else { |
| 3308 | if (checkUsingShadowRedecl<FunctionDecl>(*this, Shadow, New)) |
| 3309 | return true; |
| 3310 | OldD = Old = cast<FunctionDecl>(Shadow->getTargetDecl()); |
| 3311 | } |
| 3312 | } else { |
| 3313 | Diag(New->getLocation(), diag::err_redefinition_different_kind) |
| 3314 | << New->getDeclName(); |
| 3315 | notePreviousDefinition(OldD, New->getLocation()); |
| 3316 | return true; |
| 3317 | } |
| 3318 | } |
| 3319 | |
| 3320 | // If the old declaration was found in an inline namespace and the new |
| 3321 | // declaration was qualified, update the DeclContext to match. |
| 3322 | adjustDeclContextForDeclaratorDecl(New, Old); |
| 3323 | |
| 3324 | // If the old declaration is invalid, just give up here. |
| 3325 | if (Old->isInvalidDecl()) |
| 3326 | return true; |
| 3327 | |
| 3328 | // Disallow redeclaration of some builtins. |
| 3329 | if (!getASTContext().canBuiltinBeRedeclared(Old)) { |
| 3330 | Diag(New->getLocation(), diag::err_builtin_redeclare) << Old->getDeclName(); |
| 3331 | Diag(Old->getLocation(), diag::note_previous_builtin_declaration) |
| 3332 | << Old << Old->getType(); |
| 3333 | return true; |
| 3334 | } |
| 3335 | |
| 3336 | diag::kind PrevDiag; |
| 3337 | SourceLocation OldLocation; |
| 3338 | std::tie(PrevDiag, OldLocation) = |
| 3339 | getNoteDiagForInvalidRedeclaration(Old, New); |
| 3340 | |
| 3341 | // Don't complain about this if we're in GNU89 mode and the old function |
| 3342 | // is an extern inline function. |
| 3343 | // Don't complain about specializations. They are not supposed to have |
| 3344 | // storage classes. |
| 3345 | if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && |
| 3346 | New->getStorageClass() == SC_Static && |
| 3347 | Old->hasExternalFormalLinkage() && |
| 3348 | !New->getTemplateSpecializationInfo() && |
| 3349 | !canRedefineFunction(Old, getLangOpts())) { |
| 3350 | if (getLangOpts().MicrosoftExt) { |
| 3351 | Diag(New->getLocation(), diag::ext_static_non_static) << New; |
| 3352 | Diag(OldLocation, PrevDiag); |
| 3353 | } else { |
| 3354 | Diag(New->getLocation(), diag::err_static_non_static) << New; |
| 3355 | Diag(OldLocation, PrevDiag); |
| 3356 | return true; |
| 3357 | } |
| 3358 | } |
| 3359 | |
| 3360 | if (const auto *ILA = New->getAttr<InternalLinkageAttr>()) |
| 3361 | if (!Old->hasAttr<InternalLinkageAttr>()) { |
| 3362 | Diag(New->getLocation(), diag::err_attribute_missing_on_first_decl) |
| 3363 | << ILA; |
| 3364 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 3365 | New->dropAttr<InternalLinkageAttr>(); |
| 3366 | } |
| 3367 | |
| 3368 | if (auto *EA = New->getAttr<ErrorAttr>()) { |
| 3369 | if (!Old->hasAttr<ErrorAttr>()) { |
| 3370 | Diag(EA->getLocation(), diag::err_attribute_missing_on_first_decl) << EA; |
| 3371 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 3372 | New->dropAttr<ErrorAttr>(); |
| 3373 | } |
| 3374 | } |
| 3375 | |
| 3376 | if (CheckRedeclarationModuleOwnership(New, Old)) |
| 3377 | return true; |
| 3378 | |
| 3379 | if (!getLangOpts().CPlusPlus) { |
| 3380 | bool OldOvl = Old->hasAttr<OverloadableAttr>(); |
| 3381 | if (OldOvl != New->hasAttr<OverloadableAttr>() && !Old->isImplicit()) { |
| 3382 | Diag(New->getLocation(), diag::err_attribute_overloadable_mismatch) |
| 3383 | << New << OldOvl; |
| 3384 | |
| 3385 | // Try our best to find a decl that actually has the overloadable |
| 3386 | // attribute for the note. In most cases (e.g. programs with only one |
| 3387 | // broken declaration/definition), this won't matter. |
| 3388 | // |
| 3389 | // FIXME: We could do this if we juggled some extra state in |
| 3390 | // OverloadableAttr, rather than just removing it. |
| 3391 | const Decl *DiagOld = Old; |
| 3392 | if (OldOvl) { |
| 3393 | auto OldIter = llvm::find_if(Old->redecls(), [](const Decl *D) { |
| 3394 | const auto *A = D->getAttr<OverloadableAttr>(); |
| 3395 | return A && !A->isImplicit(); |
| 3396 | }); |
| 3397 | // If we've implicitly added *all* of the overloadable attrs to this |
| 3398 | // chain, emitting a "previous redecl" note is pointless. |
| 3399 | DiagOld = OldIter == Old->redecls_end() ? nullptr : *OldIter; |
| 3400 | } |
| 3401 | |
| 3402 | if (DiagOld) |
| 3403 | Diag(DiagOld->getLocation(), |
| 3404 | diag::note_attribute_overloadable_prev_overload) |
| 3405 | << OldOvl; |
| 3406 | |
| 3407 | if (OldOvl) |
| 3408 | New->addAttr(OverloadableAttr::CreateImplicit(Context)); |
| 3409 | else |
| 3410 | New->dropAttr<OverloadableAttr>(); |
| 3411 | } |
| 3412 | } |
| 3413 | |
| 3414 | // If a function is first declared with a calling convention, but is later |
| 3415 | // declared or defined without one, all following decls assume the calling |
| 3416 | // convention of the first. |
| 3417 | // |
| 3418 | // It's OK if a function is first declared without a calling convention, |
| 3419 | // but is later declared or defined with the default calling convention. |
| 3420 | // |
| 3421 | // To test if either decl has an explicit calling convention, we look for |
| 3422 | // AttributedType sugar nodes on the type as written. If they are missing or |
| 3423 | // were canonicalized away, we assume the calling convention was implicit. |
| 3424 | // |
| 3425 | // Note also that we DO NOT return at this point, because we still have |
| 3426 | // other tests to run. |
| 3427 | QualType OldQType = Context.getCanonicalType(Old->getType()); |
| 3428 | QualType NewQType = Context.getCanonicalType(New->getType()); |
| 3429 | const FunctionType *OldType = cast<FunctionType>(OldQType); |
| 3430 | const FunctionType *NewType = cast<FunctionType>(NewQType); |
| 3431 | FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); |
| 3432 | FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); |
| 3433 | bool RequiresAdjustment = false; |
| 3434 | |
| 3435 | if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) { |
| 3436 | FunctionDecl *First = Old->getFirstDecl(); |
| 3437 | const FunctionType *FT = |
| 3438 | First->getType().getCanonicalType()->castAs<FunctionType>(); |
| 3439 | FunctionType::ExtInfo FI = FT->getExtInfo(); |
| 3440 | bool NewCCExplicit = getCallingConvAttributedType(New->getType()); |
| 3441 | if (!NewCCExplicit) { |
| 3442 | // Inherit the CC from the previous declaration if it was specified |
| 3443 | // there but not here. |
| 3444 | NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); |
| 3445 | RequiresAdjustment = true; |
| 3446 | } else if (Old->getBuiltinID()) { |
| 3447 | // Builtin attribute isn't propagated to the new one yet at this point, |
| 3448 | // so we check if the old one is a builtin. |
| 3449 | |
| 3450 | // Calling Conventions on a Builtin aren't really useful and setting a |
| 3451 | // default calling convention and cdecl'ing some builtin redeclarations is |
| 3452 | // common, so warn and ignore the calling convention on the redeclaration. |
| 3453 | Diag(New->getLocation(), diag::warn_cconv_unsupported) |
| 3454 | << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) |
| 3455 | << (int)CallingConventionIgnoredReason::BuiltinFunction; |
| 3456 | NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); |
| 3457 | RequiresAdjustment = true; |
| 3458 | } else { |
| 3459 | // Calling conventions aren't compatible, so complain. |
| 3460 | bool FirstCCExplicit = getCallingConvAttributedType(First->getType()); |
| 3461 | Diag(New->getLocation(), diag::err_cconv_change) |
| 3462 | << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) |
| 3463 | << !FirstCCExplicit |
| 3464 | << (!FirstCCExplicit ? "" : |
| 3465 | FunctionType::getNameForCallConv(FI.getCC())); |
| 3466 | |
| 3467 | // Put the note on the first decl, since it is the one that matters. |
| 3468 | Diag(First->getLocation(), diag::note_previous_declaration); |
| 3469 | return true; |
| 3470 | } |
| 3471 | } |
| 3472 | |
| 3473 | // FIXME: diagnose the other way around? |
| 3474 | if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { |
| 3475 | NewTypeInfo = NewTypeInfo.withNoReturn(true); |
| 3476 | RequiresAdjustment = true; |
| 3477 | } |
| 3478 | |
| 3479 | // Merge regparm attribute. |
| 3480 | if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() || |
| 3481 | OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { |
| 3482 | if (NewTypeInfo.getHasRegParm()) { |
| 3483 | Diag(New->getLocation(), diag::err_regparm_mismatch) |
| 3484 | << NewType->getRegParmType() |
| 3485 | << OldType->getRegParmType(); |
| 3486 | Diag(OldLocation, diag::note_previous_declaration); |
| 3487 | return true; |
| 3488 | } |
| 3489 | |
| 3490 | NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); |
| 3491 | RequiresAdjustment = true; |
| 3492 | } |
| 3493 | |
| 3494 | // Merge ns_returns_retained attribute. |
| 3495 | if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) { |
| 3496 | if (NewTypeInfo.getProducesResult()) { |
| 3497 | Diag(New->getLocation(), diag::err_function_attribute_mismatch) |
| 3498 | << "'ns_returns_retained'"; |
| 3499 | Diag(OldLocation, diag::note_previous_declaration); |
| 3500 | return true; |
| 3501 | } |
| 3502 | |
| 3503 | NewTypeInfo = NewTypeInfo.withProducesResult(true); |
| 3504 | RequiresAdjustment = true; |
| 3505 | } |
| 3506 | |
| 3507 | if (OldTypeInfo.getNoCallerSavedRegs() != |
| 3508 | NewTypeInfo.getNoCallerSavedRegs()) { |
| 3509 | if (NewTypeInfo.getNoCallerSavedRegs()) { |
| 3510 | AnyX86NoCallerSavedRegistersAttr *Attr = |
| 3511 | New->getAttr<AnyX86NoCallerSavedRegistersAttr>(); |
| 3512 | Diag(New->getLocation(), diag::err_function_attribute_mismatch) << Attr; |
| 3513 | Diag(OldLocation, diag::note_previous_declaration); |
| 3514 | return true; |
| 3515 | } |
| 3516 | |
| 3517 | NewTypeInfo = NewTypeInfo.withNoCallerSavedRegs(true); |
| 3518 | RequiresAdjustment = true; |
| 3519 | } |
| 3520 | |
| 3521 | if (RequiresAdjustment) { |
| 3522 | const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>(); |
| 3523 | AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo); |
| 3524 | New->setType(QualType(AdjustedType, 0)); |
| 3525 | NewQType = Context.getCanonicalType(New->getType()); |
| 3526 | } |
| 3527 | |
| 3528 | // If this redeclaration makes the function inline, we may need to add it to |
| 3529 | // UndefinedButUsed. |
| 3530 | if (!Old->isInlined() && New->isInlined() && |
| 3531 | !New->hasAttr<GNUInlineAttr>() && |
| 3532 | !getLangOpts().GNUInline && |
| 3533 | Old->isUsed(false) && |
| 3534 | !Old->isDefined() && !New->isThisDeclarationADefinition()) |
| 3535 | UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(), |
| 3536 | SourceLocation())); |
| 3537 | |
| 3538 | // If this redeclaration makes it newly gnu_inline, we don't want to warn |
| 3539 | // about it. |
| 3540 | if (New->hasAttr<GNUInlineAttr>() && |
| 3541 | Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) { |
| 3542 | UndefinedButUsed.erase(Old->getCanonicalDecl()); |
| 3543 | } |
| 3544 | |
| 3545 | // If pass_object_size params don't match up perfectly, this isn't a valid |
| 3546 | // redeclaration. |
| 3547 | if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() && |
| 3548 | !hasIdenticalPassObjectSizeAttrs(Old, New)) { |
| 3549 | Diag(New->getLocation(), diag::err_different_pass_object_size_params) |
| 3550 | << New->getDeclName(); |
| 3551 | Diag(OldLocation, PrevDiag) << Old << Old->getType(); |
| 3552 | return true; |
| 3553 | } |
| 3554 | |
| 3555 | if (getLangOpts().CPlusPlus) { |
| 3556 | // C++1z [over.load]p2 |
| 3557 | // Certain function declarations cannot be overloaded: |
| 3558 | // -- Function declarations that differ only in the return type, |
| 3559 | // the exception specification, or both cannot be overloaded. |
| 3560 | |
| 3561 | // Check the exception specifications match. This may recompute the type of |
| 3562 | // both Old and New if it resolved exception specifications, so grab the |
| 3563 | // types again after this. Because this updates the type, we do this before |
| 3564 | // any of the other checks below, which may update the "de facto" NewQType |
| 3565 | // but do not necessarily update the type of New. |
| 3566 | if (CheckEquivalentExceptionSpec(Old, New)) |
| 3567 | return true; |
| 3568 | OldQType = Context.getCanonicalType(Old->getType()); |
| 3569 | NewQType = Context.getCanonicalType(New->getType()); |
| 3570 | |
| 3571 | // Go back to the type source info to compare the declared return types, |
| 3572 | // per C++1y [dcl.type.auto]p13: |
| 3573 | // Redeclarations or specializations of a function or function template |
| 3574 | // with a declared return type that uses a placeholder type shall also |
| 3575 | // use that placeholder, not a deduced type. |
| 3576 | QualType OldDeclaredReturnType = Old->getDeclaredReturnType(); |
| 3577 | QualType NewDeclaredReturnType = New->getDeclaredReturnType(); |
| 3578 | if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) && |
| 3579 | canFullyTypeCheckRedeclaration(New, Old, NewDeclaredReturnType, |
| 3580 | OldDeclaredReturnType)) { |
| 3581 | QualType ResQT; |
| 3582 | if (NewDeclaredReturnType->isObjCObjectPointerType() && |
| 3583 | OldDeclaredReturnType->isObjCObjectPointerType()) |
| 3584 | // FIXME: This does the wrong thing for a deduced return type. |
| 3585 | ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); |
| 3586 | if (ResQT.isNull()) { |
| 3587 | if (New->isCXXClassMember() && New->isOutOfLine()) |
| 3588 | Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type) |
| 3589 | << New << New->getReturnTypeSourceRange(); |
| 3590 | else |
| 3591 | Diag(New->getLocation(), diag::err_ovl_diff_return_type) |
| 3592 | << New->getReturnTypeSourceRange(); |
| 3593 | Diag(OldLocation, PrevDiag) << Old << Old->getType() |
| 3594 | << Old->getReturnTypeSourceRange(); |
| 3595 | return true; |
| 3596 | } |
| 3597 | else |
| 3598 | NewQType = ResQT; |
| 3599 | } |
| 3600 | |
| 3601 | QualType OldReturnType = OldType->getReturnType(); |
| 3602 | QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType(); |
| 3603 | if (OldReturnType != NewReturnType) { |
| 3604 | // If this function has a deduced return type and has already been |
| 3605 | // defined, copy the deduced value from the old declaration. |
| 3606 | AutoType *OldAT = Old->getReturnType()->getContainedAutoType(); |
| 3607 | if (OldAT && OldAT->isDeduced()) { |
| 3608 | New->setType( |
| 3609 | SubstAutoType(New->getType(), |
| 3610 | OldAT->isDependentType() ? Context.DependentTy |
| 3611 | : OldAT->getDeducedType())); |
| 3612 | NewQType = Context.getCanonicalType( |
| 3613 | SubstAutoType(NewQType, |
| 3614 | OldAT->isDependentType() ? Context.DependentTy |
| 3615 | : OldAT->getDeducedType())); |
| 3616 | } |
| 3617 | } |
| 3618 | |
| 3619 | const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old); |
| 3620 | CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New); |
| 3621 | if (OldMethod && NewMethod) { |
| 3622 | // Preserve triviality. |
| 3623 | NewMethod->setTrivial(OldMethod->isTrivial()); |
| 3624 | |
| 3625 | // MSVC allows explicit template specialization at class scope: |
| 3626 | // 2 CXXMethodDecls referring to the same function will be injected. |
| 3627 | // We don't want a redeclaration error. |
| 3628 | bool IsClassScopeExplicitSpecialization = |
| 3629 | OldMethod->isFunctionTemplateSpecialization() && |
| 3630 | NewMethod->isFunctionTemplateSpecialization(); |
| 3631 | bool isFriend = NewMethod->getFriendObjectKind(); |
| 3632 | |
| 3633 | if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() && |
| 3634 | !IsClassScopeExplicitSpecialization) { |
| 3635 | // -- Member function declarations with the same name and the |
| 3636 | // same parameter types cannot be overloaded if any of them |
| 3637 | // is a static member function declaration. |
| 3638 | if (OldMethod->isStatic() != NewMethod->isStatic()) { |
| 3639 | Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); |
| 3640 | Diag(OldLocation, PrevDiag) << Old << Old->getType(); |
| 3641 | return true; |
| 3642 | } |
| 3643 | |
| 3644 | // C++ [class.mem]p1: |
| 3645 | // [...] A member shall not be declared twice in the |
| 3646 | // member-specification, except that a nested class or member |
| 3647 | // class template can be declared and then later defined. |
| 3648 | if (!inTemplateInstantiation()) { |
| 3649 | unsigned NewDiag; |
| 3650 | if (isa<CXXConstructorDecl>(OldMethod)) |
| 3651 | NewDiag = diag::err_constructor_redeclared; |
| 3652 | else if (isa<CXXDestructorDecl>(NewMethod)) |
| 3653 | NewDiag = diag::err_destructor_redeclared; |
| 3654 | else if (isa<CXXConversionDecl>(NewMethod)) |
| 3655 | NewDiag = diag::err_conv_function_redeclared; |
| 3656 | else |
| 3657 | NewDiag = diag::err_member_redeclared; |
| 3658 | |
| 3659 | Diag(New->getLocation(), NewDiag); |
| 3660 | } else { |
| 3661 | Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation) |
| 3662 | << New << New->getType(); |
| 3663 | } |
| 3664 | Diag(OldLocation, PrevDiag) << Old << Old->getType(); |
| 3665 | return true; |
| 3666 | |
| 3667 | // Complain if this is an explicit declaration of a special |
| 3668 | // member that was initially declared implicitly. |
| 3669 | // |
| 3670 | // As an exception, it's okay to befriend such methods in order |
| 3671 | // to permit the implicit constructor/destructor/operator calls. |
| 3672 | } else if (OldMethod->isImplicit()) { |
| 3673 | if (isFriend) { |
| 3674 | NewMethod->setImplicit(); |
| 3675 | } else { |
| 3676 | Diag(NewMethod->getLocation(), |
| 3677 | diag::err_definition_of_implicitly_declared_member) |
| 3678 | << New << getSpecialMember(OldMethod); |
| 3679 | return true; |
| 3680 | } |
| 3681 | } else if (OldMethod->getFirstDecl()->isExplicitlyDefaulted() && !isFriend) { |
| 3682 | Diag(NewMethod->getLocation(), |
| 3683 | diag::err_definition_of_explicitly_defaulted_member) |
| 3684 | << getSpecialMember(OldMethod); |
| 3685 | return true; |
| 3686 | } |
| 3687 | } |
| 3688 | |
| 3689 | // C++11 [dcl.attr.noreturn]p1: |
| 3690 | // The first declaration of a function shall specify the noreturn |
| 3691 | // attribute if any declaration of that function specifies the noreturn |
| 3692 | // attribute. |
| 3693 | if (const auto *NRA = New->getAttr<CXX11NoReturnAttr>()) |
| 3694 | if (!Old->hasAttr<CXX11NoReturnAttr>()) { |
| 3695 | Diag(NRA->getLocation(), diag::err_attribute_missing_on_first_decl) |
| 3696 | << NRA; |
| 3697 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 3698 | } |
| 3699 | |
| 3700 | // C++11 [dcl.attr.depend]p2: |
| 3701 | // The first declaration of a function shall specify the |
| 3702 | // carries_dependency attribute for its declarator-id if any declaration |
| 3703 | // of the function specifies the carries_dependency attribute. |
| 3704 | const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>(); |
| 3705 | if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) { |
| 3706 | Diag(CDA->getLocation(), |
| 3707 | diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/; |
| 3708 | Diag(Old->getFirstDecl()->getLocation(), |
| 3709 | diag::note_carries_dependency_missing_first_decl) << 0/*Function*/; |
| 3710 | } |
| 3711 | |
| 3712 | // (C++98 8.3.5p3): |
| 3713 | // All declarations for a function shall agree exactly in both the |
| 3714 | // return type and the parameter-type-list. |
| 3715 | // We also want to respect all the extended bits except noreturn. |
| 3716 | |
| 3717 | // noreturn should now match unless the old type info didn't have it. |
| 3718 | QualType OldQTypeForComparison = OldQType; |
| 3719 | if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { |
| 3720 | auto *OldType = OldQType->castAs<FunctionProtoType>(); |
| 3721 | const FunctionType *OldTypeForComparison |
| 3722 | = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); |
| 3723 | OldQTypeForComparison = QualType(OldTypeForComparison, 0); |
| 3724 | assert(OldQTypeForComparison.isCanonical())(static_cast<void> (0)); |
| 3725 | } |
| 3726 | |
| 3727 | if (haveIncompatibleLanguageLinkages(Old, New)) { |
| 3728 | // As a special case, retain the language linkage from previous |
| 3729 | // declarations of a friend function as an extension. |
| 3730 | // |
| 3731 | // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC |
| 3732 | // and is useful because there's otherwise no way to specify language |
| 3733 | // linkage within class scope. |
| 3734 | // |
| 3735 | // Check cautiously as the friend object kind isn't yet complete. |
| 3736 | if (New->getFriendObjectKind() != Decl::FOK_None) { |
| 3737 | Diag(New->getLocation(), diag::ext_retained_language_linkage) << New; |
| 3738 | Diag(OldLocation, PrevDiag); |
| 3739 | } else { |
| 3740 | Diag(New->getLocation(), diag::err_different_language_linkage) << New; |
| 3741 | Diag(OldLocation, PrevDiag); |
| 3742 | return true; |
| 3743 | } |
| 3744 | } |
| 3745 | |
| 3746 | // If the function types are compatible, merge the declarations. Ignore the |
| 3747 | // exception specifier because it was already checked above in |
| 3748 | // CheckEquivalentExceptionSpec, and we don't want follow-on diagnostics |
| 3749 | // about incompatible types under -fms-compatibility. |
| 3750 | if (Context.hasSameFunctionTypeIgnoringExceptionSpec(OldQTypeForComparison, |
| 3751 | NewQType)) |
| 3752 | return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld); |
| 3753 | |
| 3754 | // If the types are imprecise (due to dependent constructs in friends or |
| 3755 | // local extern declarations), it's OK if they differ. We'll check again |
| 3756 | // during instantiation. |
| 3757 | if (!canFullyTypeCheckRedeclaration(New, Old, NewQType, OldQType)) |
| 3758 | return false; |
| 3759 | |
| 3760 | // Fall through for conflicting redeclarations and redefinitions. |
| 3761 | } |
| 3762 | |
| 3763 | // C: Function types need to be compatible, not identical. This handles |
| 3764 | // duplicate function decls like "void f(int); void f(enum X);" properly. |
| 3765 | if (!getLangOpts().CPlusPlus && |
| 3766 | Context.typesAreCompatible(OldQType, NewQType)) { |
| 3767 | const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); |
| 3768 | const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); |
| 3769 | const FunctionProtoType *OldProto = nullptr; |
| 3770 | if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) && |
| 3771 | (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { |
| 3772 | // The old declaration provided a function prototype, but the |
| 3773 | // new declaration does not. Merge in the prototype. |
| 3774 | assert(!OldProto->hasExceptionSpec() && "Exception spec in C")(static_cast<void> (0)); |
| 3775 | SmallVector<QualType, 16> ParamTypes(OldProto->param_types()); |
| 3776 | NewQType = |
| 3777 | Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes, |
| 3778 | OldProto->getExtProtoInfo()); |
| 3779 | New->setType(NewQType); |
| 3780 | New->setHasInheritedPrototype(); |
| 3781 | |
| 3782 | // Synthesize parameters with the same types. |
| 3783 | SmallVector<ParmVarDecl*, 16> Params; |
| 3784 | for (const auto &ParamType : OldProto->param_types()) { |
| 3785 | ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(), |
| 3786 | SourceLocation(), nullptr, |
| 3787 | ParamType, /*TInfo=*/nullptr, |
| 3788 | SC_None, nullptr); |
| 3789 | Param->setScopeInfo(0, Params.size()); |
| 3790 | Param->setImplicit(); |
| 3791 | Params.push_back(Param); |
| 3792 | } |
| 3793 | |
| 3794 | New->setParams(Params); |
| 3795 | } |
| 3796 | |
| 3797 | return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld); |
| 3798 | } |
| 3799 | |
| 3800 | // Check if the function types are compatible when pointer size address |
| 3801 | // spaces are ignored. |
| 3802 | if (Context.hasSameFunctionTypeIgnoringPtrSizes(OldQType, NewQType)) |
| 3803 | return false; |
| 3804 | |
| 3805 | // GNU C permits a K&R definition to follow a prototype declaration |
| 3806 | // if the declared types of the parameters in the K&R definition |
| 3807 | // match the types in the prototype declaration, even when the |
| 3808 | // promoted types of the parameters from the K&R definition differ |
| 3809 | // from the types in the prototype. GCC then keeps the types from |
| 3810 | // the prototype. |
| 3811 | // |
| 3812 | // If a variadic prototype is followed by a non-variadic K&R definition, |
| 3813 | // the K&R definition becomes variadic. This is sort of an edge case, but |
| 3814 | // it's legal per the standard depending on how you read C99 6.7.5.3p15 and |
| 3815 | // C99 6.9.1p8. |
| 3816 | if (!getLangOpts().CPlusPlus && |
| 3817 | Old->hasPrototype() && !New->hasPrototype() && |
| 3818 | New->getType()->getAs<FunctionProtoType>() && |
| 3819 | Old->getNumParams() == New->getNumParams()) { |
| 3820 | SmallVector<QualType, 16> ArgTypes; |
| 3821 | SmallVector<GNUCompatibleParamWarning, 16> Warnings; |
| 3822 | const FunctionProtoType *OldProto |
| 3823 | = Old->getType()->getAs<FunctionProtoType>(); |
| 3824 | const FunctionProtoType *NewProto |
| 3825 | = New->getType()->getAs<FunctionProtoType>(); |
| 3826 | |
| 3827 | // Determine whether this is the GNU C extension. |
| 3828 | QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(), |
| 3829 | NewProto->getReturnType()); |
| 3830 | bool LooseCompatible = !MergedReturn.isNull(); |
| 3831 | for (unsigned Idx = 0, End = Old->getNumParams(); |
| 3832 | LooseCompatible && Idx != End; ++Idx) { |
| 3833 | ParmVarDecl *OldParm = Old->getParamDecl(Idx); |
| 3834 | ParmVarDecl *NewParm = New->getParamDecl(Idx); |
| 3835 | if (Context.typesAreCompatible(OldParm->getType(), |
| 3836 | NewProto->getParamType(Idx))) { |
| 3837 | ArgTypes.push_back(NewParm->getType()); |
| 3838 | } else if (Context.typesAreCompatible(OldParm->getType(), |
| 3839 | NewParm->getType(), |
| 3840 | /*CompareUnqualified=*/true)) { |
| 3841 | GNUCompatibleParamWarning Warn = { OldParm, NewParm, |
| 3842 | NewProto->getParamType(Idx) }; |
| 3843 | Warnings.push_back(Warn); |
| 3844 | ArgTypes.push_back(NewParm->getType()); |
| 3845 | } else |
| 3846 | LooseCompatible = false; |
| 3847 | } |
| 3848 | |
| 3849 | if (LooseCompatible) { |
| 3850 | for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { |
| 3851 | Diag(Warnings[Warn].NewParm->getLocation(), |
| 3852 | diag::ext_param_promoted_not_compatible_with_prototype) |
| 3853 | << Warnings[Warn].PromotedType |
| 3854 | << Warnings[Warn].OldParm->getType(); |
| 3855 | if (Warnings[Warn].OldParm->getLocation().isValid()) |
| 3856 | Diag(Warnings[Warn].OldParm->getLocation(), |
| 3857 | diag::note_previous_declaration); |
| 3858 | } |
| 3859 | |
| 3860 | if (MergeTypeWithOld) |
| 3861 | New->setType(Context.getFunctionType(MergedReturn, ArgTypes, |
| 3862 | OldProto->getExtProtoInfo())); |
| 3863 | return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld); |
| 3864 | } |
| 3865 | |
| 3866 | // Fall through to diagnose conflicting types. |
| 3867 | } |
| 3868 | |
| 3869 | // A function that has already been declared has been redeclared or |
| 3870 | // defined with a different type; show an appropriate diagnostic. |
| 3871 | |
| 3872 | // If the previous declaration was an implicitly-generated builtin |
| 3873 | // declaration, then at the very least we should use a specialized note. |
| 3874 | unsigned BuiltinID; |
| 3875 | if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) { |
| 3876 | // If it's actually a library-defined builtin function like 'malloc' |
| 3877 | // or 'printf', just warn about the incompatible redeclaration. |
| 3878 | if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { |
| 3879 | Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; |
| 3880 | Diag(OldLocation, diag::note_previous_builtin_declaration) |
| 3881 | << Old << Old->getType(); |
| 3882 | return false; |
| 3883 | } |
| 3884 | |
| 3885 | PrevDiag = diag::note_previous_builtin_declaration; |
| 3886 | } |
| 3887 | |
| 3888 | Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); |
| 3889 | Diag(OldLocation, PrevDiag) << Old << Old->getType(); |
| 3890 | return true; |
| 3891 | } |
| 3892 | |
| 3893 | /// Completes the merge of two function declarations that are |
| 3894 | /// known to be compatible. |
| 3895 | /// |
| 3896 | /// This routine handles the merging of attributes and other |
| 3897 | /// properties of function declarations from the old declaration to |
| 3898 | /// the new declaration, once we know that New is in fact a |
| 3899 | /// redeclaration of Old. |
| 3900 | /// |
| 3901 | /// \returns false |
| 3902 | bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old, |
| 3903 | Scope *S, bool MergeTypeWithOld) { |
| 3904 | // Merge the attributes |
| 3905 | mergeDeclAttributes(New, Old); |
| 3906 | |
| 3907 | // Merge "pure" flag. |
| 3908 | if (Old->isPure()) |
| 3909 | New->setPure(); |
| 3910 | |
| 3911 | // Merge "used" flag. |
| 3912 | if (Old->getMostRecentDecl()->isUsed(false)) |
| 3913 | New->setIsUsed(); |
| 3914 | |
| 3915 | // Merge attributes from the parameters. These can mismatch with K&R |
| 3916 | // declarations. |
| 3917 | if (New->getNumParams() == Old->getNumParams()) |
| 3918 | for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) { |
| 3919 | ParmVarDecl *NewParam = New->getParamDecl(i); |
| 3920 | ParmVarDecl *OldParam = Old->getParamDecl(i); |
| 3921 | mergeParamDeclAttributes(NewParam, OldParam, *this); |
| 3922 | mergeParamDeclTypes(NewParam, OldParam, *this); |
| 3923 | } |
| 3924 | |
| 3925 | if (getLangOpts().CPlusPlus) |
| 3926 | return MergeCXXFunctionDecl(New, Old, S); |
| 3927 | |
| 3928 | // Merge the function types so the we get the composite types for the return |
| 3929 | // and argument types. Per C11 6.2.7/4, only update the type if the old decl |
| 3930 | // was visible. |
| 3931 | QualType Merged = Context.mergeTypes(Old->getType(), New->getType()); |
| 3932 | if (!Merged.isNull() && MergeTypeWithOld) |
| 3933 | New->setType(Merged); |
| 3934 | |
| 3935 | return false; |
| 3936 | } |
| 3937 | |
| 3938 | void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, |
| 3939 | ObjCMethodDecl *oldMethod) { |
| 3940 | // Merge the attributes, including deprecated/unavailable |
| 3941 | AvailabilityMergeKind MergeKind = |
| 3942 | isa<ObjCProtocolDecl>(oldMethod->getDeclContext()) |
| 3943 | ? (oldMethod->isOptional() ? AMK_OptionalProtocolImplementation |
| 3944 | : AMK_ProtocolImplementation) |
| 3945 | : isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration |
| 3946 | : AMK_Override; |
| 3947 | |
| 3948 | mergeDeclAttributes(newMethod, oldMethod, MergeKind); |
| 3949 | |
| 3950 | // Merge attributes from the parameters. |
| 3951 | ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(), |
| 3952 | oe = oldMethod->param_end(); |
| 3953 | for (ObjCMethodDecl::param_iterator |
| 3954 | ni = newMethod->param_begin(), ne = newMethod->param_end(); |
| 3955 | ni != ne && oi != oe; ++ni, ++oi) |
| 3956 | mergeParamDeclAttributes(*ni, *oi, *this); |
| 3957 | |
| 3958 | CheckObjCMethodOverride(newMethod, oldMethod); |
| 3959 | } |
| 3960 | |
| 3961 | static void diagnoseVarDeclTypeMismatch(Sema &S, VarDecl *New, VarDecl* Old) { |
| 3962 | assert(!S.Context.hasSameType(New->getType(), Old->getType()))(static_cast<void> (0)); |
| 3963 | |
| 3964 | S.Diag(New->getLocation(), New->isThisDeclarationADefinition() |
| 3965 | ? diag::err_redefinition_different_type |
| 3966 | : diag::err_redeclaration_different_type) |
| 3967 | << New->getDeclName() << New->getType() << Old->getType(); |
| 3968 | |
| 3969 | diag::kind PrevDiag; |
| 3970 | SourceLocation OldLocation; |
| 3971 | std::tie(PrevDiag, OldLocation) |
| 3972 | = getNoteDiagForInvalidRedeclaration(Old, New); |
| 3973 | S.Diag(OldLocation, PrevDiag); |
| 3974 | New->setInvalidDecl(); |
| 3975 | } |
| 3976 | |
| 3977 | /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and |
| 3978 | /// scope as a previous declaration 'Old'. Figure out how to merge their types, |
| 3979 | /// emitting diagnostics as appropriate. |
| 3980 | /// |
| 3981 | /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back |
| 3982 | /// to here in AddInitializerToDecl. We can't check them before the initializer |
| 3983 | /// is attached. |
| 3984 | void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old, |
| 3985 | bool MergeTypeWithOld) { |
| 3986 | if (New->isInvalidDecl() || Old->isInvalidDecl()) |
| 3987 | return; |
| 3988 | |
| 3989 | QualType MergedT; |
| 3990 | if (getLangOpts().CPlusPlus) { |
| 3991 | if (New->getType()->isUndeducedType()) { |
| 3992 | // We don't know what the new type is until the initializer is attached. |
| 3993 | return; |
| 3994 | } else if (Context.hasSameType(New->getType(), Old->getType())) { |
| 3995 | // These could still be something that needs exception specs checked. |
| 3996 | return MergeVarDeclExceptionSpecs(New, Old); |
| 3997 | } |
| 3998 | // C++ [basic.link]p10: |
| 3999 | // [...] the types specified by all declarations referring to a given |
| 4000 | // object or function shall be identical, except that declarations for an |
| 4001 | // array object can specify array types that differ by the presence or |
| 4002 | // absence of a major array bound (8.3.4). |
| 4003 | else if (Old->getType()->isArrayType() && New->getType()->isArrayType()) { |
| 4004 | const ArrayType *OldArray = Context.getAsArrayType(Old->getType()); |
| 4005 | const ArrayType *NewArray = Context.getAsArrayType(New->getType()); |
| 4006 | |
| 4007 | // We are merging a variable declaration New into Old. If it has an array |
| 4008 | // bound, and that bound differs from Old's bound, we should diagnose the |
| 4009 | // mismatch. |
| 4010 | if (!NewArray->isIncompleteArrayType() && !NewArray->isDependentType()) { |
| 4011 | for (VarDecl *PrevVD = Old->getMostRecentDecl(); PrevVD; |
| 4012 | PrevVD = PrevVD->getPreviousDecl()) { |
| 4013 | QualType PrevVDTy = PrevVD->getType(); |
| 4014 | if (PrevVDTy->isIncompleteArrayType() || PrevVDTy->isDependentType()) |
| 4015 | continue; |
| 4016 | |
| 4017 | if (!Context.hasSameType(New->getType(), PrevVDTy)) |
| 4018 | return diagnoseVarDeclTypeMismatch(*this, New, PrevVD); |
| 4019 | } |
| 4020 | } |
| 4021 | |
| 4022 | if (OldArray->isIncompleteArrayType() && NewArray->isArrayType()) { |
| 4023 | if (Context.hasSameType(OldArray->getElementType(), |
| 4024 | NewArray->getElementType())) |
| 4025 | MergedT = New->getType(); |
| 4026 | } |
| 4027 | // FIXME: Check visibility. New is hidden but has a complete type. If New |
| 4028 | // has no array bound, it should not inherit one from Old, if Old is not |
| 4029 | // visible. |
| 4030 | else if (OldArray->isArrayType() && NewArray->isIncompleteArrayType()) { |
| 4031 | if (Context.hasSameType(OldArray->getElementType(), |
| 4032 | NewArray->getElementType())) |
| 4033 | MergedT = Old->getType(); |
| 4034 | } |
| 4035 | } |
| 4036 | else if (New->getType()->isObjCObjectPointerType() && |
| 4037 | Old->getType()->isObjCObjectPointerType()) { |
| 4038 | MergedT = Context.mergeObjCGCQualifiers(New->getType(), |
| 4039 | Old->getType()); |
| 4040 | } |
| 4041 | } else { |
| 4042 | // C 6.2.7p2: |
| 4043 | // All declarations that refer to the same object or function shall have |
| 4044 | // compatible type. |
| 4045 | MergedT = Context.mergeTypes(New->getType(), Old->getType()); |
| 4046 | } |
| 4047 | if (MergedT.isNull()) { |
| 4048 | // It's OK if we couldn't merge types if either type is dependent, for a |
| 4049 | // block-scope variable. In other cases (static data members of class |
| 4050 | // templates, variable templates, ...), we require the types to be |
| 4051 | // equivalent. |
| 4052 | // FIXME: The C++ standard doesn't say anything about this. |
| 4053 | if ((New->getType()->isDependentType() || |
| 4054 | Old->getType()->isDependentType()) && New->isLocalVarDecl()) { |
| 4055 | // If the old type was dependent, we can't merge with it, so the new type |
| 4056 | // becomes dependent for now. We'll reproduce the original type when we |
| 4057 | // instantiate the TypeSourceInfo for the variable. |
| 4058 | if (!New->getType()->isDependentType() && MergeTypeWithOld) |
| 4059 | New->setType(Context.DependentTy); |
| 4060 | return; |
| 4061 | } |
| 4062 | return diagnoseVarDeclTypeMismatch(*this, New, Old); |
| 4063 | } |
| 4064 | |
| 4065 | // Don't actually update the type on the new declaration if the old |
| 4066 | // declaration was an extern declaration in a different scope. |
| 4067 | if (MergeTypeWithOld) |
| 4068 | New->setType(MergedT); |
| 4069 | } |
| 4070 | |
| 4071 | static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD, |
| 4072 | LookupResult &Previous) { |
| 4073 | // C11 6.2.7p4: |
| 4074 | // For an identifier with internal or external linkage declared |
| 4075 | // in a scope in which a prior declaration of that identifier is |
| 4076 | // visible, if the prior declaration specifies internal or |
| 4077 | // external linkage, the type of the identifier at the later |
| 4078 | // declaration becomes the composite type. |
| 4079 | // |
| 4080 | // If the variable isn't visible, we do not merge with its type. |
| 4081 | if (Previous.isShadowed()) |
| 4082 | return false; |
| 4083 | |
| 4084 | if (S.getLangOpts().CPlusPlus) { |
| 4085 | // C++11 [dcl.array]p3: |
| 4086 | // If there is a preceding declaration of the entity in the same |
| 4087 | // scope in which the bound was specified, an omitted array bound |
| 4088 | // is taken to be the same as in that earlier declaration. |
| 4089 | return NewVD->isPreviousDeclInSameBlockScope() || |
| 4090 | (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() && |
| 4091 | !NewVD->getLexicalDeclContext()->isFunctionOrMethod()); |
| 4092 | } else { |
| 4093 | // If the old declaration was function-local, don't merge with its |
| 4094 | // type unless we're in the same function. |
| 4095 | return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() || |
| 4096 | OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext(); |
| 4097 | } |
| 4098 | } |
| 4099 | |
| 4100 | /// MergeVarDecl - We just parsed a variable 'New' which has the same name |
| 4101 | /// and scope as a previous declaration 'Old'. Figure out how to resolve this |
| 4102 | /// situation, merging decls or emitting diagnostics as appropriate. |
| 4103 | /// |
| 4104 | /// Tentative definition rules (C99 6.9.2p2) are checked by |
| 4105 | /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative |
| 4106 | /// definitions here, since the initializer hasn't been attached. |
| 4107 | /// |
| 4108 | void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { |
| 4109 | // If the new decl is already invalid, don't do any other checking. |
| 4110 | if (New->isInvalidDecl()) |
| 4111 | return; |
| 4112 | |
| 4113 | if (!shouldLinkPossiblyHiddenDecl(Previous, New)) |
| 4114 | return; |
| 4115 | |
| 4116 | VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate(); |
| 4117 | |
| 4118 | // Verify the old decl was also a variable or variable template. |
| 4119 | VarDecl *Old = nullptr; |
| 4120 | VarTemplateDecl *OldTemplate = nullptr; |
| 4121 | if (Previous.isSingleResult()) { |
| 4122 | if (NewTemplate) { |
| 4123 | OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl()); |
| 4124 | Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr; |
| 4125 | |
| 4126 | if (auto *Shadow = |
| 4127 | dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl())) |
| 4128 | if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate)) |
| 4129 | return New->setInvalidDecl(); |
| 4130 | } else { |
| 4131 | Old = dyn_cast<VarDecl>(Previous.getFoundDecl()); |
| 4132 | |
| 4133 | if (auto *Shadow = |
| 4134 | dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl())) |
| 4135 | if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New)) |
| 4136 | return New->setInvalidDecl(); |
| 4137 | } |
| 4138 | } |
| 4139 | if (!Old) { |
| 4140 | Diag(New->getLocation(), diag::err_redefinition_different_kind) |
| 4141 | << New->getDeclName(); |
| 4142 | notePreviousDefinition(Previous.getRepresentativeDecl(), |
| 4143 | New->getLocation()); |
| 4144 | return New->setInvalidDecl(); |
| 4145 | } |
| 4146 | |
| 4147 | // If the old declaration was found in an inline namespace and the new |
| 4148 | // declaration was qualified, update the DeclContext to match. |
| 4149 | adjustDeclContextForDeclaratorDecl(New, Old); |
| 4150 | |
| 4151 | // Ensure the template parameters are compatible. |
| 4152 | if (NewTemplate && |
| 4153 | !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(), |
| 4154 | OldTemplate->getTemplateParameters(), |
| 4155 | /*Complain=*/true, TPL_TemplateMatch)) |
| 4156 | return New->setInvalidDecl(); |
| 4157 | |
| 4158 | // C++ [class.mem]p1: |
| 4159 | // A member shall not be declared twice in the member-specification [...] |
| 4160 | // |
| 4161 | // Here, we need only consider static data members. |
| 4162 | if (Old->isStaticDataMember() && !New->isOutOfLine()) { |
| 4163 | Diag(New->getLocation(), diag::err_duplicate_member) |
| 4164 | << New->getIdentifier(); |
| 4165 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 4166 | New->setInvalidDecl(); |
| 4167 | } |
| 4168 | |
| 4169 | mergeDeclAttributes(New, Old); |
| 4170 | // Warn if an already-declared variable is made a weak_import in a subsequent |
| 4171 | // declaration |
| 4172 | if (New->hasAttr<WeakImportAttr>() && |
| 4173 | Old->getStorageClass() == SC_None && |
| 4174 | !Old->hasAttr<WeakImportAttr>()) { |
| 4175 | Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName(); |
| 4176 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 4177 | // Remove weak_import attribute on new declaration. |
| 4178 | New->dropAttr<WeakImportAttr>(); |
| 4179 | } |
| 4180 | |
| 4181 | if (const auto *ILA = New->getAttr<InternalLinkageAttr>()) |
| 4182 | if (!Old->hasAttr<InternalLinkageAttr>()) { |
| 4183 | Diag(New->getLocation(), diag::err_attribute_missing_on_first_decl) |
| 4184 | << ILA; |
| 4185 | Diag(Old->getLocation(), diag::note_previous_declaration); |
| 4186 | New->dropAttr<InternalLinkageAttr>(); |
| 4187 | } |
| 4188 | |
| 4189 | // Merge the types. |
| 4190 | VarDecl *MostRecent = Old->getMostRecentDecl(); |
| 4191 | if (MostRecent != Old) { |
| 4192 | MergeVarDeclTypes(New, MostRecent, |
| 4193 | mergeTypeWithPrevious(*this, New, MostRecent, Previous)); |
| 4194 | if (New->isInvalidDecl()) |
| 4195 | return; |
| 4196 | } |
| 4197 | |
| 4198 | MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous)); |
| 4199 | if (New->isInvalidDecl()) |
| 4200 | return; |
| 4201 | |
| 4202 | diag::kind PrevDiag; |
| 4203 | SourceLocation OldLocation; |
| 4204 | std::tie(PrevDiag, OldLocation) = |
| 4205 | getNoteDiagForInvalidRedeclaration(Old, New); |
| 4206 | |
| 4207 | // [dcl.stc]p8: Check if we have a non-static decl followed by a static. |
| 4208 | if (New->getStorageClass() == SC_Static && |
| 4209 | !New->isStaticDataMember() && |
| 4210 | Old->hasExternalFormalLinkage()) { |
| 4211 | if (getLangOpts().MicrosoftExt) { |
| 4212 | Diag(New->getLocation(), diag::ext_static_non_static) |
| 4213 | << New->getDeclName(); |
| 4214 | Diag(OldLocation, PrevDiag); |
| 4215 | } else { |
| 4216 | Diag(New->getLocation(), diag::err_static_non_static) |
| 4217 | << New->getDeclName(); |
| 4218 | Diag(OldLocation, PrevDiag); |
| 4219 | return New->setInvalidDecl(); |
| 4220 | } |
| 4221 | } |
| 4222 | // C99 6.2.2p4: |
| 4223 | // For an identifier declared with the storage-class specifier |
| 4224 | // extern in a scope in which a prior declaration of that |
| 4225 | // identifier is visible,23) if the prior declaration specifies |
| 4226 | // internal or external linkage, the linkage of the identifier at |
| 4227 | // the later declaration is the same as the linkage specified at |
| 4228 | // the prior declaration. If no prior declaration is visible, or |
| 4229 | // if the prior declaration specifies no linkage, then the |
| 4230 | // identifier has external linkage. |
| 4231 | if (New->hasExternalStorage() && Old->hasLinkage()) |
| 4232 | /* Okay */; |
| 4233 | else if (New->getCanonicalDecl()->getStorageClass() != SC_Static && |
| 4234 | !New->isStaticDataMember() && |
| 4235 | Old->getCanonicalDecl()->getStorageClass() == SC_Static) { |
| 4236 | Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); |
| 4237 | Diag(OldLocation, PrevDiag); |
| 4238 | return New->setInvalidDecl(); |
| 4239 | } |
| 4240 | |
| 4241 | // Check if extern is followed by non-extern and vice-versa. |
| 4242 | if (New->hasExternalStorage() && |
| 4243 | !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) { |
| 4244 | Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); |
| 4245 | Diag(OldLocation, PrevDiag); |
| 4246 | return New->setInvalidDecl(); |
| 4247 | } |
| 4248 | if (Old->hasLinkage() && New->isLocalVarDeclOrParm() && |
| 4249 | !New->hasExternalStorage()) { |
| 4250 | Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); |
| 4251 | Diag(OldLocation, PrevDiag); |
| 4252 | return New->setInvalidDecl(); |
| 4253 | } |
| 4254 | |
| 4255 | if (CheckRedeclarationModuleOwnership(New, Old)) |
| 4256 | return; |
| 4257 | |
| 4258 | // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. |
| 4259 | |
| 4260 | // FIXME: The test for external storage here seems wrong? We still |
| 4261 | // need to check for mismatches. |
| 4262 | if (!New->hasExternalStorage() && !New->isFileVarDecl() && |
| 4263 | // Don't complain about out-of-line definitions of static members. |
| 4264 | !(Old->getLexicalDeclContext()->isRecord() && |
| 4265 | !New->getLexicalDeclContext()->isRecord())) { |
| 4266 | Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); |
| 4267 | Diag(OldLocation, PrevDiag); |
| 4268 | return New->setInvalidDecl(); |
| 4269 | } |
| 4270 | |
| 4271 | if (New->isInline() && !Old->getMostRecentDecl()->isInline()) { |
| 4272 | if (VarDecl *Def = Old->getDefinition()) { |
| 4273 | // C++1z [dcl.fcn.spec]p4: |
| 4274 | // If the definition of a variable appears in a translation unit before |
| 4275 | // its first declaration as inline, the program is ill-formed. |
| 4276 | Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New; |
| 4277 | Diag(Def->getLocation(), diag::note_previous_definition); |
| 4278 | } |
| 4279 | } |
| 4280 | |
| 4281 | // If this redeclaration makes the variable inline, we may need to add it to |
| 4282 | // UndefinedButUsed. |
| 4283 | if (!Old->isInline() && New->isInline() && Old->isUsed(false) && |
| 4284 | !Old->getDefinition() && !New->isThisDeclarationADefinition()) |
| 4285 | UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(), |
| 4286 | SourceLocation())); |
| 4287 | |
| 4288 | if (New->getTLSKind() != Old->getTLSKind()) { |
| 4289 | if (!Old->getTLSKind()) { |
| 4290 | Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); |
| 4291 | Diag(OldLocation, PrevDiag); |
| 4292 | } else if (!New->getTLSKind()) { |
| 4293 | Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); |
| 4294 | Diag(OldLocation, PrevDiag); |
| 4295 | } else { |
| 4296 | // Do not allow redeclaration to change the variable between requiring |
| 4297 | // static and dynamic initialization. |
| 4298 | // FIXME: GCC allows this, but uses the TLS keyword on the first |
| 4299 | // declaration to determine the kind. Do we need to be compatible here? |
| 4300 | Diag(New->getLocation(), diag::err_thread_thread_different_kind) |
| 4301 | << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic); |
| 4302 | Diag(OldLocation, PrevDiag); |
| 4303 | } |
| 4304 | } |
| 4305 | |
| 4306 | // C++ doesn't have tentative definitions, so go right ahead and check here. |
| 4307 | if (getLangOpts().CPlusPlus && |
| 4308 | New->isThisDeclarationADefinition() == VarDecl::Definition) { |
| 4309 | if (Old->isStaticDataMember() && Old->getCanonicalDecl()->isInline() && |
| 4310 | Old->getCanonicalDecl()->isConstexpr()) { |
| 4311 | // This definition won't be a definition any more once it's been merged. |
| 4312 | Diag(New->getLocation(), |
| 4313 | diag::warn_deprecated_redundant_constexpr_static_def); |
| 4314 | } else if (VarDecl *Def = Old->getDefinition()) { |
| 4315 | if (checkVarDeclRedefinition(Def, New)) |
| 4316 | return; |
| 4317 | } |
| 4318 | } |
| 4319 | |
| 4320 | if (haveIncompatibleLanguageLinkages(Old, New)) { |
| 4321 | Diag(New->getLocation(), diag::err_different_language_linkage) << New; |
| 4322 | Diag(OldLocation, PrevDiag); |
| 4323 | New->setInvalidDecl(); |
| 4324 | return; |
| 4325 | } |
| 4326 | |
| 4327 | // Merge "used" flag. |
| 4328 | if (Old->getMostRecentDecl()->isUsed(false)) |
| 4329 | New->setIsUsed(); |
| 4330 | |
| 4331 | // Keep a chain of previous declarations. |
| 4332 | New->setPreviousDecl(Old); |
| 4333 | if (NewTemplate) |
| 4334 | NewTemplate->setPreviousDecl(OldTemplate); |
| 4335 | |
| 4336 | // Inherit access appropriately. |
| 4337 | New->setAccess(Old->getAccess()); |
| 4338 | if (NewTemplate) |
| 4339 | NewTemplate->setAccess(New->getAccess()); |
| 4340 | |
| 4341 | if (Old->isInline()) |
| 4342 | New->setImplicitlyInline(); |
| 4343 | } |
| 4344 | |
| 4345 | void Sema::notePreviousDefinition(const NamedDecl *Old, SourceLocation New) { |
| 4346 | SourceManager &SrcMgr = getSourceManager(); |
| 4347 | auto FNewDecLoc = SrcMgr.getDecomposedLoc(New); |
| 4348 | auto FOldDecLoc = SrcMgr.getDecomposedLoc(Old->getLocation()); |
| 4349 | auto *FNew = SrcMgr.getFileEntryForID(FNewDecLoc.first); |
| 4350 | auto *FOld = SrcMgr.getFileEntryForID(FOldDecLoc.first); |
| 4351 | auto &HSI = PP.getHeaderSearchInfo(); |
| 4352 | StringRef HdrFilename = |
| 4353 | SrcMgr.getFilename(SrcMgr.getSpellingLoc(Old->getLocation())); |
| 4354 | |
| 4355 | auto noteFromModuleOrInclude = [&](Module *Mod, |
| 4356 | SourceLocation IncLoc) -> bool { |
| 4357 | // Redefinition errors with modules are common with non modular mapped |
| 4358 | // headers, example: a non-modular header H in module A that also gets |
| 4359 | // included directly in a TU. Pointing twice to the same header/definition |
| 4360 | // is confusing, try to get better diagnostics when modules is on. |
| 4361 | if (IncLoc.isValid()) { |
| 4362 | if (Mod) { |
| 4363 | Diag(IncLoc, diag::note_redefinition_modules_same_file) |
| 4364 | << HdrFilename.str() << Mod->getFullModuleName(); |
| 4365 | if (!Mod->DefinitionLoc.isInvalid()) |
| 4366 | Diag(Mod->DefinitionLoc, diag::note_defined_here) |
| 4367 | << Mod->getFullModuleName(); |
| 4368 | } else { |
| 4369 | Diag(IncLoc, diag::note_redefinition_include_same_file) |
| 4370 | << HdrFilename.str(); |
| 4371 | } |
| 4372 | return true; |
| 4373 | } |
| 4374 | |
| 4375 | return false; |
| 4376 | }; |
| 4377 | |
| 4378 | // Is it the same file and same offset? Provide more information on why |
| 4379 | // this leads to a redefinition error. |
| 4380 | if (FNew == FOld && FNewDecLoc.second == FOldDecLoc.second) { |
| 4381 | SourceLocation OldIncLoc = SrcMgr.getIncludeLoc(FOldDecLoc.first); |
| 4382 | SourceLocation NewIncLoc = SrcMgr.getIncludeLoc(FNewDecLoc.first); |
| 4383 | bool EmittedDiag = |
| 4384 | noteFromModuleOrInclude(Old->getOwningModule(), OldIncLoc); |
| 4385 | EmittedDiag |= noteFromModuleOrInclude(getCurrentModule(), NewIncLoc); |
| 4386 | |
| 4387 | // If the header has no guards, emit a note suggesting one. |
| 4388 | if (FOld && !HSI.isFileMultipleIncludeGuarded(FOld)) |
| 4389 | Diag(Old->getLocation(), diag::note_use_ifdef_guards); |
| 4390 | |
| 4391 | if (EmittedDiag) |
| 4392 | return; |
| 4393 | } |
| 4394 | |
| 4395 | // Redefinition coming from different files or couldn't do better above. |
| 4396 | if (Old->getLocation().isValid()) |
| 4397 | Diag(Old->getLocation(), diag::note_previous_definition); |
| 4398 | } |
| 4399 | |
| 4400 | /// We've just determined that \p Old and \p New both appear to be definitions |
| 4401 | /// of the same variable. Either diagnose or fix the problem. |
| 4402 | bool Sema::checkVarDeclRedefinition(VarDecl *Old, VarDecl *New) { |
| 4403 | if (!hasVisibleDefinition(Old) && |
| 4404 | (New->getFormalLinkage() == InternalLinkage || |
| 4405 | New->isInline() || |
| 4406 | New->getDescribedVarTemplate() || |
| 4407 | New->getNumTemplateParameterLists() || |
| 4408 | New->getDeclContext()->isDependentContext())) { |
| 4409 | // The previous definition is hidden, and multiple definitions are |
| 4410 | // permitted (in separate TUs). Demote this to a declaration. |
| 4411 | New->demoteThisDefinitionToDeclaration(); |
| 4412 | |
| 4413 | // Make the canonical definition visible. |
| 4414 | if (auto *OldTD = Old->getDescribedVarTemplate()) |
| 4415 | makeMergedDefinitionVisible(OldTD); |
| 4416 | makeMergedDefinitionVisible(Old); |
| 4417 | return false; |
| 4418 | } else { |
| 4419 | Diag(New->getLocation(), diag::err_redefinition) << New; |
| 4420 | notePreviousDefinition(Old, New->getLocation()); |
| 4421 | New->setInvalidDecl(); |
| 4422 | return true; |
| 4423 | } |
| 4424 | } |
| 4425 | |
| 4426 | /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with |
| 4427 | /// no declarator (e.g. "struct foo;") is parsed. |
| 4428 | Decl * |
| 4429 | Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS, |
| 4430 | RecordDecl *&AnonRecord) { |
| 4431 | return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg(), false, |
| 4432 | AnonRecord); |
| 4433 | } |
| 4434 | |
| 4435 | // The MS ABI changed between VS2013 and VS2015 with regard to numbers used to |
| 4436 | // disambiguate entities defined in different scopes. |
| 4437 | // While the VS2015 ABI fixes potential miscompiles, it is also breaks |
| 4438 | // compatibility. |
| 4439 | // We will pick our mangling number depending on which version of MSVC is being |
| 4440 | // targeted. |
| 4441 | static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) { |
| 4442 | return LO.isCompatibleWithMSVC(LangOptions::MSVC2015) |
| 4443 | ? S->getMSCurManglingNumber() |
| 4444 | : S->getMSLastManglingNumber(); |
| 4445 | } |
| 4446 | |
| 4447 | void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) { |
| 4448 | if (!Context.getLangOpts().CPlusPlus) |
| 4449 | return; |
| 4450 | |
| 4451 | if (isa<CXXRecordDecl>(Tag->getParent())) { |
| 4452 | // If this tag is the direct child of a class, number it if |
| 4453 | // it is anonymous. |
| 4454 | if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl()) |
| 4455 | return; |
| 4456 | MangleNumberingContext &MCtx = |
| 4457 | Context.getManglingNumberContext(Tag->getParent()); |
| 4458 | Context.setManglingNumber( |
| 4459 | Tag, MCtx.getManglingNumber( |
| 4460 | Tag, getMSManglingNumber(getLangOpts(), TagScope))); |
| 4461 | return; |
| 4462 | } |
| 4463 | |
| 4464 | // If this tag isn't a direct child of a class, number it if it is local. |
| 4465 | MangleNumberingContext *MCtx; |
| 4466 | Decl *ManglingContextDecl; |
| 4467 | std::tie(MCtx, ManglingContextDecl) = |
| 4468 | getCurrentMangleNumberContext(Tag->getDeclContext()); |
| 4469 | if (MCtx) { |
| 4470 | Context.setManglingNumber( |
| 4471 | Tag, MCtx->getManglingNumber( |
| 4472 | Tag, getMSManglingNumber(getLangOpts(), TagScope))); |
| 4473 | } |
| 4474 | } |
| 4475 | |
| 4476 | namespace { |
| 4477 | struct NonCLikeKind { |
| 4478 | enum { |
| 4479 | None, |
| 4480 | BaseClass, |
| 4481 | DefaultMemberInit, |
| 4482 | Lambda, |
| 4483 | Friend, |
| 4484 | OtherMember, |
| 4485 | Invalid, |
| 4486 | } Kind = None; |
| 4487 | SourceRange Range; |
| 4488 | |
| 4489 | explicit operator bool() { return Kind != None; } |
| 4490 | }; |
| 4491 | } |
| 4492 | |
| 4493 | /// Determine whether a class is C-like, according to the rules of C++ |
| 4494 | /// [dcl.typedef] for anonymous classes with typedef names for linkage. |
| 4495 | static NonCLikeKind getNonCLikeKindForAnonymousStruct(const CXXRecordDecl *RD) { |
| 4496 | if (RD->isInvalidDecl()) |
| 4497 | return {NonCLikeKind::Invalid, {}}; |
| 4498 | |
| 4499 | // C++ [dcl.typedef]p9: [P1766R1] |
| 4500 | // An unnamed class with a typedef name for linkage purposes shall not |
| 4501 | // |
| 4502 | // -- have any base classes |
| 4503 | if (RD->getNumBases()) |
| 4504 | return {NonCLikeKind::BaseClass, |
| 4505 | SourceRange(RD->bases_begin()->getBeginLoc(), |
| 4506 | RD->bases_end()[-1].getEndLoc())}; |
| 4507 | bool Invalid = false; |
| 4508 | for (Decl *D : RD->decls()) { |
| 4509 | // Don't complain about things we already diagnosed. |
| 4510 | if (D->isInvalidDecl()) { |
| 4511 | Invalid = true; |
| 4512 | continue; |
| 4513 | } |
| 4514 | |
| 4515 | // -- have any [...] default member initializers |
| 4516 | if (auto *FD = dyn_cast<FieldDecl>(D)) { |
| 4517 | if (FD->hasInClassInitializer()) { |
| 4518 | auto *Init = FD->getInClassInitializer(); |
| 4519 | return {NonCLikeKind::DefaultMemberInit, |
| 4520 | Init ? Init->getSourceRange() : D->getSourceRange()}; |
| 4521 | } |
| 4522 | continue; |
| 4523 | } |
| 4524 | |
| 4525 | // FIXME: We don't allow friend declarations. This violates the wording of |
| 4526 | // P1766, but not the intent. |
| 4527 | if (isa<FriendDecl>(D)) |
| 4528 | return {NonCLikeKind::Friend, D->getSourceRange()}; |
| 4529 | |
| 4530 | // -- declare any members other than non-static data members, member |
| 4531 | // enumerations, or member classes, |
| 4532 | if (isa<StaticAssertDecl>(D) || isa<IndirectFieldDecl>(D) || |
| 4533 | isa<EnumDecl>(D)) |
| 4534 | continue; |
| 4535 | auto *MemberRD = dyn_cast<CXXRecordDecl>(D); |
| 4536 | if (!MemberRD) { |
| 4537 | if (D->isImplicit()) |
| 4538 | continue; |
| 4539 | return {NonCLikeKind::OtherMember, D->getSourceRange()}; |
| 4540 | } |
| 4541 | |
| 4542 | // -- contain a lambda-expression, |
| 4543 | if (MemberRD->isLambda()) |
| 4544 | return {NonCLikeKind::Lambda, MemberRD->getSourceRange()}; |
| 4545 | |
| 4546 | // and all member classes shall also satisfy these requirements |
| 4547 | // (recursively). |
| 4548 | if (MemberRD->isThisDeclarationADefinition()) { |
| 4549 | if (auto Kind = getNonCLikeKindForAnonymousStruct(MemberRD)) |
| 4550 | return Kind; |
| 4551 | } |
| 4552 | } |
| 4553 | |
| 4554 | return {Invalid ? NonCLikeKind::Invalid : NonCLikeKind::None, {}}; |
| 4555 | } |
| 4556 | |
| 4557 | void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec, |
| 4558 | TypedefNameDecl *NewTD) { |
| 4559 | if (TagFromDeclSpec->isInvalidDecl()) |
| 4560 | return; |
| 4561 | |
| 4562 | // Do nothing if the tag already has a name for linkage purposes. |
| 4563 | if (TagFromDeclSpec->hasNameForLinkage()) |
| 4564 | return; |
| 4565 | |
| 4566 | // A well-formed anonymous tag must always be a TUK_Definition. |
| 4567 | assert(TagFromDeclSpec->isThisDeclarationADefinition())(static_cast<void> (0)); |
| 4568 | |
| 4569 | // The type must match the tag exactly; no qualifiers allowed. |
| 4570 | if (!Context.hasSameType(NewTD->getUnderlyingType(), |
| 4571 | Context.getTagDeclType(TagFromDeclSpec))) { |
| 4572 | if (getLangOpts().CPlusPlus) |
| 4573 | Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD); |
| 4574 | return; |
| 4575 | } |
| 4576 | |
| 4577 | // C++ [dcl.typedef]p9: [P1766R1, applied as DR] |
| 4578 | // An unnamed class with a typedef name for linkage purposes shall [be |
| 4579 | // C-like]. |
| 4580 | // |
| 4581 | // FIXME: Also diagnose if we've already computed the linkage. That ideally |
| 4582 | // shouldn't happen, but there are constructs that the language rule doesn't |
| 4583 | // disallow for which we can't reasonably avoid computing linkage early. |
| 4584 | const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TagFromDeclSpec); |
| 4585 | NonCLikeKind NonCLike = RD ? getNonCLikeKindForAnonymousStruct(RD) |
| 4586 | : NonCLikeKind(); |
| 4587 | bool ChangesLinkage = TagFromDeclSpec->hasLinkageBeenComputed(); |
| 4588 | if (NonCLike || ChangesLinkage) { |
| 4589 | if (NonCLike.Kind == NonCLikeKind::Invalid) |
| 4590 | return; |
| 4591 | |
| 4592 | unsigned DiagID = diag::ext_non_c_like_anon_struct_in_typedef; |
| 4593 | if (ChangesLinkage) { |
| 4594 | // If the linkage changes, we can't accept this as an extension. |
| 4595 | if (NonCLike.Kind == NonCLikeKind::None) |
| 4596 | DiagID = diag::err_typedef_changes_linkage; |
| 4597 | else |
| 4598 | DiagID = diag::err_non_c_like_anon_struct_in_typedef; |
| 4599 | } |
| 4600 | |
| 4601 | SourceLocation FixitLoc = |
| 4602 | getLocForEndOfToken(TagFromDeclSpec->getInnerLocStart()); |
| 4603 | llvm::SmallString<40> TextToInsert; |
| 4604 | TextToInsert += ' '; |
| 4605 | TextToInsert += NewTD->getIdentifier()->getName(); |
| 4606 | |
| 4607 | Diag(FixitLoc, DiagID) |
| 4608 | << isa<TypeAliasDecl>(NewTD) |
| 4609 | << FixItHint::CreateInsertion(FixitLoc, TextToInsert); |
| 4610 | if (NonCLike.Kind != NonCLikeKind::None) { |
| 4611 | Diag(NonCLike.Range.getBegin(), diag::note_non_c_like_anon_struct) |
| 4612 | << NonCLike.Kind - 1 << NonCLike.Range; |
| 4613 | } |
| 4614 | Diag(NewTD->getLocation(), diag::note_typedef_for_linkage_here) |
| 4615 | << NewTD << isa<TypeAliasDecl>(NewTD); |
| 4616 | |
| 4617 | if (ChangesLinkage) |
| 4618 | return; |
| 4619 | } |
| 4620 | |
| 4621 | // Otherwise, set this as the anon-decl typedef for the tag. |
| 4622 | TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD); |
| 4623 | } |
| 4624 | |
| 4625 | static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) { |
| 4626 | switch (T) { |
| 4627 | case DeclSpec::TST_class: |
| 4628 | return 0; |
| 4629 | case DeclSpec::TST_struct: |
| 4630 | return 1; |
| 4631 | case DeclSpec::TST_interface: |
| 4632 | return 2; |
| 4633 | case DeclSpec::TST_union: |
| 4634 | return 3; |
| 4635 | case DeclSpec::TST_enum: |
| 4636 | return 4; |
| 4637 | default: |
| 4638 | llvm_unreachable("unexpected type specifier")__builtin_unreachable(); |
| 4639 | } |
| 4640 | } |
| 4641 | |
| 4642 | /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with |
| 4643 | /// no declarator (e.g. "struct foo;") is parsed. It also accepts template |
| 4644 | /// parameters to cope with template friend declarations. |
| 4645 | Decl * |
| 4646 | Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS, |
| 4647 | MultiTemplateParamsArg TemplateParams, |
| 4648 | bool IsExplicitInstantiation, |
| 4649 | RecordDecl *&AnonRecord) { |
| 4650 | Decl *TagD = nullptr; |
| 4651 | TagDecl *Tag = nullptr; |
| 4652 | if (DS.getTypeSpecType() == DeclSpec::TST_class || |
| 4653 | DS.getTypeSpecType() == DeclSpec::TST_struct || |
| 4654 | DS.getTypeSpecType() == DeclSpec::TST_interface || |
| 4655 | DS.getTypeSpecType() == DeclSpec::TST_union || |
| 4656 | DS.getTypeSpecType() == DeclSpec::TST_enum) { |
| 4657 | TagD = DS.getRepAsDecl(); |
| 4658 | |
| 4659 | if (!TagD) // We probably had an error |
| 4660 | return nullptr; |
| 4661 | |
| 4662 | // Note that the above type specs guarantee that the |
| 4663 | // type rep is a Decl, whereas in many of the others |
| 4664 | // it's a Type. |
| 4665 | if (isa<TagDecl>(TagD)) |
| 4666 | Tag = cast<TagDecl>(TagD); |
| 4667 | else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD)) |
| 4668 | Tag = CTD->getTemplatedDecl(); |
| 4669 | } |
| 4670 | |
| 4671 | if (Tag) { |
| 4672 | handleTagNumbering(Tag, S); |
| 4673 | Tag->setFreeStanding(); |
| 4674 | if (Tag->isInvalidDecl()) |
| 4675 | return Tag; |
| 4676 | } |
| 4677 | |
| 4678 | if (unsigned TypeQuals = DS.getTypeQualifiers()) { |
| 4679 | // Enforce C99 6.7.3p2: "Types other than pointer types derived from object |
| 4680 | // or incomplete types shall not be restrict-qualified." |
| 4681 | if (TypeQuals & DeclSpec::TQ_restrict) |
| 4682 | Diag(DS.getRestrictSpecLoc(), |
| 4683 | diag::err_typecheck_invalid_restrict_not_pointer_noarg) |
| 4684 | << DS.getSourceRange(); |
| 4685 | } |
| 4686 | |
| 4687 | if (DS.isInlineSpecified()) |
| 4688 | Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function) |
| 4689 | << getLangOpts().CPlusPlus17; |
| 4690 | |
| 4691 | if (DS.hasConstexprSpecifier()) { |
| 4692 | // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations |
| 4693 | // and definitions of functions and variables. |
| 4694 | // C++2a [dcl.constexpr]p1: The consteval specifier shall be applied only to |
| 4695 | // the declaration of a function or function template |
| 4696 | if (Tag) |
| 4697 | Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag) |
| 4698 | << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) |
| 4699 | << static_cast<int>(DS.getConstexprSpecifier()); |
| 4700 | else |
| 4701 | Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_wrong_decl_kind) |
| 4702 | << static_cast<int>(DS.getConstexprSpecifier()); |
| 4703 | // Don't emit warnings after this error. |
| 4704 | return TagD; |
| 4705 | } |
| 4706 | |
| 4707 | DiagnoseFunctionSpecifiers(DS); |
| 4708 | |
| 4709 | if (DS.isFriendSpecified()) { |
| 4710 | // If we're dealing with a decl but not a TagDecl, assume that |
| 4711 | // whatever routines created it handled the friendship aspect. |
| 4712 | if (TagD && !Tag) |
| 4713 | return nullptr; |
| 4714 | return ActOnFriendTypeDecl(S, DS, TemplateParams); |
| 4715 | } |
| 4716 | |
| 4717 | const CXXScopeSpec &SS = DS.getTypeSpecScope(); |
| 4718 | bool IsExplicitSpecialization = |
| 4719 | !TemplateParams.empty() && TemplateParams.back()->size() == 0; |
| 4720 | if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() && |
| 4721 | !IsExplicitInstantiation && !IsExplicitSpecialization && |
| 4722 | !isa<ClassTemplatePartialSpecializationDecl>(Tag)) { |
| 4723 | // Per C++ [dcl.type.elab]p1, a class declaration cannot have a |
| 4724 | // nested-name-specifier unless it is an explicit instantiation |
| 4725 | // or an explicit specialization. |
| 4726 | // |
| 4727 | // FIXME: We allow class template partial specializations here too, per the |
| 4728 | // obvious intent of DR1819. |
| 4729 | // |
| 4730 | // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either. |
| 4731 | Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier) |
| 4732 | << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange(); |
| 4733 | return nullptr; |
| 4734 | } |
| 4735 | |
| 4736 | // Track whether this decl-specifier declares anything. |
| 4737 | bool DeclaresAnything = true; |
| 4738 | |
| 4739 | // Handle anonymous struct definitions. |
| 4740 | if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { |
| 4741 | if (!Record->getDeclName() && Record->isCompleteDefinition() && |
| 4742 | DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { |
| 4743 | if (getLangOpts().CPlusPlus || |
| 4744 | Record->getDeclContext()->isRecord()) { |
| 4745 | // If CurContext is a DeclContext that can contain statements, |
| 4746 | // RecursiveASTVisitor won't visit the decls that |
| 4747 | // BuildAnonymousStructOrUnion() will put into CurContext. |
| 4748 | // Also store them here so that they can be part of the |
| 4749 | // DeclStmt that gets created in this case. |
| 4750 | // FIXME: Also return the IndirectFieldDecls created by |
| 4751 | // BuildAnonymousStructOr union, for the same reason? |
| 4752 | if (CurContext->isFunctionOrMethod()) |
| 4753 | AnonRecord = Record; |
| 4754 | return BuildAnonymousStructOrUnion(S, DS, AS, Record, |
| 4755 | Context.getPrintingPolicy()); |
| 4756 | } |
| 4757 | |
| 4758 | DeclaresAnything = false; |
| 4759 | } |
| 4760 | } |
| 4761 | |
| 4762 | // C11 6.7.2.1p2: |
| 4763 | // A struct-declaration that does not declare an anonymous structure or |
| 4764 | // anonymous union shall contain a struct-declarator-list. |
| 4765 | // |
| 4766 | // This rule also existed in C89 and C99; the grammar for struct-declaration |
| 4767 | // did not permit a struct-declaration without a struct-declarator-list. |
| 4768 | if (!getLangOpts().CPlusPlus && CurContext->isRecord() && |
| 4769 | DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { |
| 4770 | // Check for Microsoft C extension: anonymous struct/union member. |
| 4771 | // Handle 2 kinds of anonymous struct/union: |
| 4772 | // struct STRUCT; |
| 4773 | // union UNION; |
| 4774 | // and |
| 4775 | // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. |
| 4776 | // UNION_TYPE; <- where UNION_TYPE is a typedef union. |
| 4777 | if ((Tag && Tag->getDeclName()) || |
| 4778 | DS.getTypeSpecType() == DeclSpec::TST_typename) { |
| 4779 | RecordDecl *Record = nullptr; |
| 4780 | if (Tag) |
| 4781 | Record = dyn_cast<RecordDecl>(Tag); |
| 4782 | else if (const RecordType *RT = |
| 4783 | DS.getRepAsType().get()->getAsStructureType()) |
| 4784 | Record = RT->getDecl(); |
| 4785 | else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType()) |
| 4786 | Record = UT->getDecl(); |
| 4787 | |
| 4788 | if (Record && getLangOpts().MicrosoftExt) { |
| 4789 | Diag(DS.getBeginLoc(), diag::ext_ms_anonymous_record) |
| 4790 | << Record->isUnion() << DS.getSourceRange(); |
| 4791 | return BuildMicrosoftCAnonymousStruct(S, DS, Record); |
| 4792 | } |
| 4793 | |
| 4794 | DeclaresAnything = false; |
| 4795 | } |
| 4796 | } |
| 4797 | |
| 4798 | // Skip all the checks below if we have a type error. |
| 4799 | if (DS.getTypeSpecType() == DeclSpec::TST_error || |
| 4800 | (TagD && TagD->isInvalidDecl())) |
| 4801 | return TagD; |
| 4802 | |
| 4803 | if (getLangOpts().CPlusPlus && |
| 4804 | DS.getStorageClassSpec() != DeclSpec::SCS_typedef) |
| 4805 | if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) |
| 4806 | if (Enum->enumerator_begin() == Enum->enumerator_end() && |
| 4807 | !Enum->getIdentifier() && !Enum->isInvalidDecl()) |
| 4808 | DeclaresAnything = false; |
| 4809 | |
| 4810 | if (!DS.isMissingDeclaratorOk()) { |
| 4811 | // Customize diagnostic for a typedef missing a name. |
| 4812 | if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) |
| 4813 | Diag(DS.getBeginLoc(), diag::ext_typedef_without_a_name) |
| 4814 | << DS.getSourceRange(); |
| 4815 | else |
| 4816 | DeclaresAnything = false; |
| 4817 | } |
| 4818 | |
| 4819 | if (DS.isModulePrivateSpecified() && |
| 4820 | Tag && Tag->getDeclContext()->isFunctionOrMethod()) |
| 4821 | Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class) |
| 4822 | << Tag->getTagKind() |
| 4823 | << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc()); |
| 4824 | |
| 4825 | ActOnDocumentableDecl(TagD); |
| 4826 | |
| 4827 | // C 6.7/2: |
| 4828 | // A declaration [...] shall declare at least a declarator [...], a tag, |
| 4829 | // or the members of an enumeration. |
| 4830 | // C++ [dcl.dcl]p3: |
| 4831 | // [If there are no declarators], and except for the declaration of an |
| 4832 | // unnamed bit-field, the decl-specifier-seq shall introduce one or more |
| 4833 | // names into the program, or shall redeclare a name introduced by a |
| 4834 | // previous declaration. |
| 4835 | if (!DeclaresAnything) { |
| 4836 | // In C, we allow this as a (popular) extension / bug. Don't bother |
| 4837 | // producing further diagnostics for redundant qualifiers after this. |
| 4838 | Diag(DS.getBeginLoc(), (IsExplicitInstantiation || !TemplateParams.empty()) |
| 4839 | ? diag::err_no_declarators |
| 4840 | : diag::ext_no_declarators) |
| 4841 | << DS.getSourceRange(); |
| 4842 | return TagD; |
| 4843 | } |
| 4844 | |
| 4845 | // C++ [dcl.stc]p1: |
| 4846 | // If a storage-class-specifier appears in a decl-specifier-seq, [...] the |
| 4847 | // init-declarator-list of the declaration shall not be empty. |
| 4848 | // C++ [dcl.fct.spec]p1: |
| 4849 | // If a cv-qualifier appears in a decl-specifier-seq, the |
| 4850 | // init-declarator-list of the declaration shall not be empty. |
| 4851 | // |
| 4852 | // Spurious qualifiers here appear to be valid in C. |
| 4853 | unsigned DiagID = diag::warn_standalone_specifier; |
| 4854 | if (getLangOpts().CPlusPlus) |
| 4855 | DiagID = diag::ext_standalone_specifier; |
| 4856 | |
| 4857 | // Note that a linkage-specification sets a storage class, but |
| 4858 | // 'extern "C" struct foo;' is actually valid and not theoretically |
| 4859 | // useless. |
| 4860 | if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) { |
| 4861 | if (SCS == DeclSpec::SCS_mutable) |
| 4862 | // Since mutable is not a viable storage class specifier in C, there is |
| 4863 | // no reason to treat it as an extension. Instead, diagnose as an error. |
| 4864 | Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember); |
| 4865 | else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef) |
| 4866 | Diag(DS.getStorageClassSpecLoc(), DiagID) |
| 4867 | << DeclSpec::getSpecifierName(SCS); |
| 4868 | } |
| 4869 | |
| 4870 | if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec()) |
| 4871 | Diag(DS.getThreadStorageClassSpecLoc(), DiagID) |
| 4872 | << DeclSpec::getSpecifierName(TSCS); |
| 4873 | if (DS.getTypeQualifiers()) { |
| 4874 | if (DS.getTypeQualifiers() & DeclSpec::TQ_const) |
| 4875 | Diag(DS.getConstSpecLoc(), DiagID) << "const"; |
| 4876 | if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) |
| 4877 | Diag(DS.getConstSpecLoc(), DiagID) << "volatile"; |
| 4878 | // Restrict is covered above. |
| 4879 | if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic) |
| 4880 | Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic"; |
| 4881 | if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned) |
| 4882 | Diag(DS.getUnalignedSpecLoc(), DiagID) << "__unaligned"; |
| 4883 | } |
| 4884 | |
| 4885 | // Warn about ignored type attributes, for example: |
| 4886 | // __attribute__((aligned)) struct A; |
| 4887 | // Attributes should be placed after tag to apply to type declaration. |
| 4888 | if (!DS.getAttributes().empty()) { |
| 4889 | DeclSpec::TST TypeSpecType = DS.getTypeSpecType(); |
| 4890 | if (TypeSpecType == DeclSpec::TST_class || |
| 4891 | TypeSpecType == DeclSpec::TST_struct || |
| 4892 | TypeSpecType == DeclSpec::TST_interface || |
| 4893 | TypeSpecType == DeclSpec::TST_union || |
| 4894 | TypeSpecType == DeclSpec::TST_enum) { |
| 4895 | for (const ParsedAttr &AL : DS.getAttributes()) |
| 4896 | Diag(AL.getLoc(), diag::warn_declspec_attribute_ignored) |
| 4897 | << AL << GetDiagnosticTypeSpecifierID(TypeSpecType); |
| 4898 | } |
| 4899 | } |
| 4900 | |
| 4901 | return TagD; |
| 4902 | } |
| 4903 | |
| 4904 | /// We are trying to inject an anonymous member into the given scope; |
| 4905 | /// check if there's an existing declaration that can't be overloaded. |
| 4906 | /// |
| 4907 | /// \return true if this is a forbidden redeclaration |
| 4908 | static bool CheckAnonMemberRedeclaration(Sema &SemaRef, |
| 4909 | Scope *S, |
| 4910 | DeclContext *Owner, |
| 4911 | DeclarationName Name, |
| 4912 | SourceLocation NameLoc, |
| 4913 | bool IsUnion) { |
| 4914 | LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, |
| 4915 | Sema::ForVisibleRedeclaration); |
| 4916 | if (!SemaRef.LookupName(R, S)) return false; |
| 4917 | |
| 4918 | // Pick a representative declaration. |
| 4919 | NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); |
| 4920 | assert(PrevDecl && "Expected a non-null Decl")(static_cast<void> (0)); |
| 4921 | |
| 4922 | if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) |
| 4923 | return false; |
| 4924 | |
| 4925 | SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl) |
| 4926 | << IsUnion << Name; |
| 4927 | SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); |
| 4928 | |
| 4929 | return true; |
| 4930 | } |
| 4931 | |
| 4932 | /// InjectAnonymousStructOrUnionMembers - Inject the members of the |
| 4933 | /// anonymous struct or union AnonRecord into the owning context Owner |
| 4934 | /// and scope S. This routine will be invoked just after we realize |
| 4935 | /// that an unnamed union or struct is actually an anonymous union or |
| 4936 | /// struct, e.g., |
| 4937 | /// |
| 4938 | /// @code |
| 4939 | /// union { |
| 4940 | /// int i; |
| 4941 | /// float f; |
| 4942 | /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and |
| 4943 | /// // f into the surrounding scope.x |
| 4944 | /// @endcode |
| 4945 | /// |
| 4946 | /// This routine is recursive, injecting the names of nested anonymous |
| 4947 | /// structs/unions into the owning context and scope as well. |
| 4948 | static bool |
| 4949 | InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner, |
| 4950 | RecordDecl *AnonRecord, AccessSpecifier AS, |
| 4951 | SmallVectorImpl<NamedDecl *> &Chaining) { |
| 4952 | bool Invalid = false; |
| 4953 | |
| 4954 | // Look every FieldDecl and IndirectFieldDecl with a name. |
| 4955 | for (auto *D : AnonRecord->decls()) { |
| 4956 | if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) && |
| 4957 | cast<NamedDecl>(D)->getDeclName()) { |
| 4958 | ValueDecl *VD = cast<ValueDecl>(D); |
| 4959 | if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), |
| 4960 | VD->getLocation(), |
| 4961 | AnonRecord->isUnion())) { |
| 4962 | // C++ [class.union]p2: |
| 4963 | // The names of the members of an anonymous union shall be |
| 4964 | // distinct from the names of any other entity in the |
| 4965 | // scope in which the anonymous union is declared. |
| 4966 | Invalid = true; |
| 4967 | } else { |
| 4968 | // C++ [class.union]p2: |
| 4969 | // For the purpose of name lookup, after the anonymous union |
| 4970 | // definition, the members of the anonymous union are |
| 4971 | // considered to have been defined in the scope in which the |
| 4972 | // anonymous union is declared. |
| 4973 | unsigned OldChainingSize = Chaining.size(); |
| 4974 | if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) |
| 4975 | Chaining.append(IF->chain_begin(), IF->chain_end()); |
| 4976 | else |
| 4977 | Chaining.push_back(VD); |
| 4978 | |
| 4979 | assert(Chaining.size() >= 2)(static_cast<void> (0)); |
| 4980 | NamedDecl **NamedChain = |
| 4981 | new (SemaRef.Context)NamedDecl*[Chaining.size()]; |
| 4982 | for (unsigned i = 0; i < Chaining.size(); i++) |
| 4983 | NamedChain[i] = Chaining[i]; |
| 4984 | |
| 4985 | IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create( |
| 4986 | SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(), |
| 4987 | VD->getType(), {NamedChain, Chaining.size()}); |
| 4988 | |
| 4989 | for (const auto *Attr : VD->attrs()) |
| 4990 | IndirectField->addAttr(Attr->clone(SemaRef.Context)); |
| 4991 | |
| 4992 | IndirectField->setAccess(AS); |
| 4993 | IndirectField->setImplicit(); |
| 4994 | SemaRef.PushOnScopeChains(IndirectField, S); |
| 4995 | |
| 4996 | // That includes picking up the appropriate access specifier. |
| 4997 | if (AS != AS_none) IndirectField->setAccess(AS); |
| 4998 | |
| 4999 | Chaining.resize(OldChainingSize); |
| 5000 | } |
| 5001 | } |
| 5002 | } |
| 5003 | |
| 5004 | return Invalid; |
| 5005 | } |
| 5006 | |
| 5007 | /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to |
| 5008 | /// a VarDecl::StorageClass. Any error reporting is up to the caller: |
| 5009 | /// illegal input values are mapped to SC_None. |
| 5010 | static StorageClass |
| 5011 | StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) { |
| 5012 | DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec(); |
| 5013 | assert(StorageClassSpec != DeclSpec::SCS_typedef &&(static_cast<void> (0)) |
| 5014 | "Parser allowed 'typedef' as storage class VarDecl.")(static_cast<void> (0)); |
| 5015 | switch (StorageClassSpec) { |
| 5016 | case DeclSpec::SCS_unspecified: return SC_None; |
| 5017 | case DeclSpec::SCS_extern: |
| 5018 | if (DS.isExternInLinkageSpec()) |
| 5019 | return SC_None; |
| 5020 | return SC_Extern; |
| 5021 | case DeclSpec::SCS_static: return SC_Static; |
| 5022 | case DeclSpec::SCS_auto: return SC_Auto; |
| 5023 | case DeclSpec::SCS_register: return SC_Register; |
| 5024 | case DeclSpec::SCS_private_extern: return SC_PrivateExtern; |
| 5025 | // Illegal SCSs map to None: error reporting is up to the caller. |
| 5026 | case DeclSpec::SCS_mutable: // Fall through. |
| 5027 | case DeclSpec::SCS_typedef: return SC_None; |
| 5028 | } |
| 5029 | llvm_unreachable("unknown storage class specifier")__builtin_unreachable(); |
| 5030 | } |
| 5031 | |
| 5032 | static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) { |
| 5033 | assert(Record->hasInClassInitializer())(static_cast<void> (0)); |
| 5034 | |
| 5035 | for (const auto *I : Record->decls()) { |
| 5036 | const auto *FD = dyn_cast<FieldDecl>(I); |
| 5037 | if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I)) |
| 5038 | FD = IFD->getAnonField(); |
| 5039 | if (FD && FD->hasInClassInitializer()) |
| 5040 | return FD->getLocation(); |
| 5041 | } |
| 5042 | |
| 5043 | llvm_unreachable("couldn't find in-class initializer")__builtin_unreachable(); |
| 5044 | } |
| 5045 | |
| 5046 | static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent, |
| 5047 | SourceLocation DefaultInitLoc) { |
| 5048 | if (!Parent->isUnion() || !Parent->hasInClassInitializer()) |
| 5049 | return; |
| 5050 | |
| 5051 | S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization); |
| 5052 | S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0; |
| 5053 | } |
| 5054 | |
| 5055 | static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent, |
| 5056 | CXXRecordDecl *AnonUnion) { |
| 5057 | if (!Parent->isUnion() || !Parent->hasInClassInitializer()) |
| 5058 | return; |
| 5059 | |
| 5060 | checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion)); |
| 5061 | } |
| 5062 | |
| 5063 | /// BuildAnonymousStructOrUnion - Handle the declaration of an |
| 5064 | /// anonymous structure or union. Anonymous unions are a C++ feature |
| 5065 | /// (C++ [class.union]) and a C11 feature; anonymous structures |
| 5066 | /// are a C11 feature and GNU C++ extension. |
| 5067 | Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, |
| 5068 | AccessSpecifier AS, |
| 5069 | RecordDecl *Record, |
| 5070 | const PrintingPolicy &Policy) { |
| 5071 | DeclContext *Owner = Record->getDeclContext(); |
| 5072 | |
| 5073 | // Diagnose whether this anonymous struct/union is an extension. |
| 5074 | if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11) |
| 5075 | Diag(Record->getLocation(), diag::ext_anonymous_union); |
| 5076 | else if (!Record->isUnion() && getLangOpts().CPlusPlus) |
| 5077 | Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct); |
| 5078 | else if (!Record->isUnion() && !getLangOpts().C11) |
| 5079 | Diag(Record->getLocation(), diag::ext_c11_anonymous_struct); |
| 5080 | |
| 5081 | // C and C++ require different kinds of checks for anonymous |
| 5082 | // structs/unions. |
| 5083 | bool Invalid = false; |
| 5084 | if (getLangOpts().CPlusPlus) { |
| 5085 | const char *PrevSpec = nullptr; |
| 5086 | if (Record->isUnion()) { |
| 5087 | // C++ [class.union]p6: |
| 5088 | // C++17 [class.union.anon]p2: |
| 5089 | // Anonymous unions declared in a named namespace or in the |
| 5090 | // global namespace shall be declared static. |
| 5091 | unsigned DiagID; |
| 5092 | DeclContext *OwnerScope = Owner->getRedeclContext(); |
| 5093 | if (DS.getStorageClassSpec() != DeclSpec::SCS_static && |
| 5094 | (OwnerScope->isTranslationUnit() || |
| 5095 | (OwnerScope->isNamespace() && |
| 5096 | !cast<NamespaceDecl>(OwnerScope)->isAnonymousNamespace()))) { |
| 5097 | Diag(Record->getLocation(), diag::err_anonymous_union_not_static) |
| 5098 | << FixItHint::CreateInsertion(Record->getLocation(), "static "); |
| 5099 | |
| 5100 | // Recover by adding 'static'. |
| 5101 | DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(), |
| 5102 | PrevSpec, DiagID, Policy); |
| 5103 | } |
| 5104 | // C++ [class.union]p6: |
| 5105 | // A storage class is not allowed in a declaration of an |
| 5106 | // anonymous union in a class scope. |
| 5107 | else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && |
| 5108 | isa<RecordDecl>(Owner)) { |
| 5109 | Diag(DS.getStorageClassSpecLoc(), |
| 5110 | diag::err_anonymous_union_with_storage_spec) |
| 5111 | << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc()); |
| 5112 | |
| 5113 | // Recover by removing the storage specifier. |
| 5114 | DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified, |
| 5115 | SourceLocation(), |
| 5116 | PrevSpec, DiagID, Context.getPrintingPolicy()); |
| 5117 | } |
| 5118 | } |
| 5119 | |
| 5120 | // Ignore const/volatile/restrict qualifiers. |
| 5121 | if (DS.getTypeQualifiers()) { |
| 5122 | if (DS.getTypeQualifiers() & DeclSpec::TQ_const) |
| 5123 | Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified) |
| 5124 | << Record->isUnion() << "const" |
| 5125 | << FixItHint::CreateRemoval(DS.getConstSpecLoc()); |
| 5126 | if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) |
| 5127 | Diag(DS.getVolatileSpecLoc(), |
| 5128 | diag::ext_anonymous_struct_union_qualified) |
| 5129 | << Record->isUnion() << "volatile" |
| 5130 | << FixItHint::CreateRemoval(DS.getVolatileSpecLoc()); |
| 5131 | if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict) |
| 5132 | Diag(DS.getRestrictSpecLoc(), |
| 5133 | diag::ext_anonymous_struct_union_qualified) |
| 5134 | << Record->isUnion() << "restrict" |
| 5135 | << FixItHint::CreateRemoval(DS.getRestrictSpecLoc()); |
| 5136 | if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic) |
| 5137 | Diag(DS.getAtomicSpecLoc(), |
| 5138 | diag::ext_anonymous_struct_union_qualified) |
| 5139 | << Record->isUnion() << "_Atomic" |
| 5140 | << FixItHint::CreateRemoval(DS.getAtomicSpecLoc()); |
| 5141 | if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned) |
| 5142 | Diag(DS.getUnalignedSpecLoc(), |
| 5143 | diag::ext_anonymous_struct_union_qualified) |
| 5144 | << Record->isUnion() << "__unaligned" |
| 5145 | << FixItHint::CreateRemoval(DS.getUnalignedSpecLoc()); |
| 5146 | |
| 5147 | DS.ClearTypeQualifiers(); |
| 5148 | } |
| 5149 | |
| 5150 | // C++ [class.union]p2: |
| 5151 | // The member-specification of an anonymous union shall only |
| 5152 | // define non-static data members. [Note: nested types and |
| 5153 | // functions cannot be declared within an anonymous union. ] |
| 5154 | for (auto *Mem : Record->decls()) { |
| 5155 | // Ignore invalid declarations; we already diagnosed them. |
| 5156 | if (Mem->isInvalidDecl()) |
| 5157 | continue; |
| 5158 | |
| 5159 | if (auto *FD = dyn_cast<FieldDecl>(Mem)) { |
| 5160 | // C++ [class.union]p3: |
| 5161 | // An anonymous union shall not have private or protected |
| 5162 | // members (clause 11). |
| 5163 | assert(FD->getAccess() != AS_none)(static_cast<void> (0)); |
| 5164 | if (FD->getAccess() != AS_public) { |
| 5165 | Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) |
| 5166 | << Record->isUnion() << (FD->getAccess() == AS_protected); |
| 5167 | Invalid = true; |
| 5168 | } |
| 5169 | |
| 5170 | // C++ [class.union]p1 |
| 5171 | // An object of a class with a non-trivial constructor, a non-trivial |
| 5172 | // copy constructor, a non-trivial destructor, or a non-trivial copy |
| 5173 | // assignment operator cannot be a member of a union, nor can an |
| 5174 | // array of such objects. |
| 5175 | if (CheckNontrivialField(FD)) |
| 5176 | Invalid = true; |
| 5177 | } else if (Mem->isImplicit()) { |
| 5178 | // Any implicit members are fine. |
| 5179 | } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) { |
| 5180 | // This is a type that showed up in an |
| 5181 | // elaborated-type-specifier inside the anonymous struct or |
| 5182 | // union, but which actually declares a type outside of the |
| 5183 | // anonymous struct or union. It's okay. |
| 5184 | } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) { |
| 5185 | if (!MemRecord->isAnonymousStructOrUnion() && |
| 5186 | MemRecord->getDeclName()) { |
| 5187 | // Visual C++ allows type definition in anonymous struct or union. |
| 5188 | if (getLangOpts().MicrosoftExt) |
| 5189 | Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) |
| 5190 | << Record->isUnion(); |
| 5191 | else { |
| 5192 | // This is a nested type declaration. |
| 5193 | Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) |
| 5194 | << Record->isUnion(); |
| 5195 | Invalid = true; |
| 5196 | } |
| 5197 | } else { |
| 5198 | // This is an anonymous type definition within another anonymous type. |
| 5199 | // This is a popular extension, provided by Plan9, MSVC and GCC, but |
| 5200 | // not part of standard C++. |
| 5201 | Diag(MemRecord->getLocation(), |
| 5202 | diag::ext_anonymous_record_with_anonymous_type) |
| 5203 | << Record->isUnion(); |
| 5204 | } |
| 5205 | } else if (isa<AccessSpecDecl>(Mem)) { |
| 5206 | // Any access specifier is fine. |
| 5207 | } else if (isa<StaticAssertDecl>(Mem)) { |
| 5208 | // In C++1z, static_assert declarations are also fine. |
| 5209 | } else { |
| 5210 | // We have something that isn't a non-static data |
| 5211 | // member. Complain about it. |
| 5212 | unsigned DK = diag::err_anonymous_record_bad_member; |
| 5213 | if (isa<TypeDecl>(Mem)) |
| 5214 | DK = diag::err_anonymous_record_with_type; |
| 5215 | else if (isa<FunctionDecl>(Mem)) |
| 5216 | DK = diag::err_anonymous_record_with_function; |
| 5217 | else if (isa<VarDecl>(Mem)) |
| 5218 | DK = diag::err_anonymous_record_with_static; |
| 5219 | |
| 5220 | // Visual C++ allows type definition in anonymous struct or union. |
| 5221 | if (getLangOpts().MicrosoftExt && |
| 5222 | DK == diag::err_anonymous_record_with_type) |
| 5223 | Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type) |
| 5224 | << Record->isUnion(); |
| 5225 | else { |
| 5226 | Diag(Mem->getLocation(), DK) << Record->isUnion(); |
| 5227 | Invalid = true; |
| 5228 | } |
| 5229 | } |
| 5230 | } |
| 5231 | |
| 5232 | // C++11 [class.union]p8 (DR1460): |
| 5233 | // At most one variant member of a union may have a |
| 5234 | // brace-or-equal-initializer. |
| 5235 | if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() && |
| 5236 | Owner->isRecord()) |
| 5237 | checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner), |
| 5238 | cast<CXXRecordDecl>(Record)); |
| 5239 | } |
| 5240 | |
| 5241 | if (!Record->isUnion() && !Owner->isRecord()) { |
| 5242 | Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) |
| 5243 | << getLangOpts().CPlusPlus; |
| 5244 | Invalid = true; |
| 5245 | } |
| 5246 | |
| 5247 | // C++ [dcl.dcl]p3: |
| 5248 | // [If there are no declarators], and except for the declaration of an |
| 5249 | // unnamed bit-field, the decl-specifier-seq shall introduce one or more |
| 5250 | // names into the program |
| 5251 | // C++ [class.mem]p2: |
| 5252 | // each such member-declaration shall either declare at least one member |
| 5253 | // name of the class or declare at least one unnamed bit-field |
| 5254 | // |
| 5255 | // For C this is an error even for a named struct, and is diagnosed elsewhere. |
| 5256 | if (getLangOpts().CPlusPlus && Record->field_empty()) |
| 5257 | Diag(DS.getBeginLoc(), diag::ext_no_declarators) << DS.getSourceRange(); |
| 5258 | |
| 5259 | // Mock up a declarator. |
| 5260 | Declarator Dc(DS, DeclaratorContext::Member); |
| 5261 | TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); |
| 5262 | assert(TInfo && "couldn't build declarator info for anonymous struct/union")(static_cast<void> (0)); |
| 5263 | |
| 5264 | // Create a declaration for this anonymous struct/union. |
| 5265 | NamedDecl *Anon = nullptr; |
| 5266 | if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { |
| 5267 | Anon = FieldDecl::Create( |
| 5268 | Context, OwningClass, DS.getBeginLoc(), Record->getLocation(), |
| 5269 | /*IdentifierInfo=*/nullptr, Context.getTypeDeclType(Record), TInfo, |
| 5270 | /*BitWidth=*/nullptr, /*Mutable=*/false, |
| 5271 | /*InitStyle=*/ICIS_NoInit); |
| 5272 | Anon->setAccess(AS); |
| 5273 | ProcessDeclAttributes(S, Anon, Dc); |
| 5274 | |
| 5275 | if (getLangOpts().CPlusPlus) |
| 5276 | FieldCollector->Add(cast<FieldDecl>(Anon)); |
| 5277 | } else { |
| 5278 | DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); |
| 5279 | StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS); |
| 5280 | if (SCSpec == DeclSpec::SCS_mutable) { |
| 5281 | // mutable can only appear on non-static class members, so it's always |
| 5282 | // an error here |
| 5283 | Diag(Record->getLocation(), diag::err_mutable_nonmember); |
| 5284 | Invalid = true; |
| 5285 | SC = SC_None; |
| 5286 | } |
| 5287 | |
| 5288 | assert(DS.getAttributes().empty() && "No attribute expected")(static_cast<void> (0)); |
| 5289 | Anon = VarDecl::Create(Context, Owner, DS.getBeginLoc(), |
| 5290 | Record->getLocation(), /*IdentifierInfo=*/nullptr, |
| 5291 | Context.getTypeDeclType(Record), TInfo, SC); |
| 5292 | |
| 5293 | // Default-initialize the implicit variable. This initialization will be |
| 5294 | // trivial in almost all cases, except if a union member has an in-class |
| 5295 | // initializer: |
| 5296 | // union { int n = 0; }; |
| 5297 | if (!Invalid) |
| 5298 | ActOnUninitializedDecl(Anon); |
| 5299 | } |
| 5300 | Anon->setImplicit(); |
| 5301 | |
| 5302 | // Mark this as an anonymous struct/union type. |
| 5303 | Record->setAnonymousStructOrUnion(true); |
| 5304 | |
| 5305 | // Add the anonymous struct/union object to the current |
| 5306 | // context. We'll be referencing this object when we refer to one of |
| 5307 | // its members. |
| 5308 | Owner->addDecl(Anon); |
| 5309 | |
| 5310 | // Inject the members of the anonymous struct/union into the owning |
| 5311 | // context and into the identifier resolver chain for name lookup |
| 5312 | // purposes. |
| 5313 | SmallVector<NamedDecl*, 2> Chain; |
| 5314 | Chain.push_back(Anon); |
| 5315 | |
| 5316 | if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain)) |
| 5317 | Invalid = true; |
| 5318 | |
| 5319 | if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) { |
| 5320 | if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) { |
| 5321 | MangleNumberingContext *MCtx; |
| 5322 | Decl *ManglingContextDecl; |
| 5323 | std::tie(MCtx, ManglingContextDecl) = |
| 5324 | getCurrentMangleNumberContext(NewVD->getDeclContext()); |
| 5325 | if (MCtx) { |
| 5326 | Context.setManglingNumber( |
| 5327 | NewVD, MCtx->getManglingNumber( |
| 5328 | NewVD, getMSManglingNumber(getLangOpts(), S))); |
| 5329 | Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD)); |
| 5330 | } |
| 5331 | } |
| 5332 | } |
| 5333 | |
| 5334 | if (Invalid) |
| 5335 | Anon->setInvalidDecl(); |
| 5336 | |
| 5337 | return Anon; |
| 5338 | } |
| 5339 | |
| 5340 | /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an |
| 5341 | /// Microsoft C anonymous structure. |
| 5342 | /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx |
| 5343 | /// Example: |
| 5344 | /// |
| 5345 | /// struct A { int a; }; |
| 5346 | /// struct B { struct A; int b; }; |
| 5347 | /// |
| 5348 | /// void foo() { |
| 5349 | /// B var; |
| 5350 | /// var.a = 3; |
| 5351 | /// } |
| 5352 | /// |
| 5353 | Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, |
| 5354 | RecordDecl *Record) { |
| 5355 | assert(Record && "expected a record!")(static_cast<void> (0)); |
| 5356 | |
| 5357 | // Mock up a declarator. |
| 5358 | Declarator Dc(DS, DeclaratorContext::TypeName); |
| 5359 | TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); |
| 5360 | assert(TInfo && "couldn't build declarator info for anonymous struct")(static_cast<void> (0)); |
| 5361 | |
| 5362 | auto *ParentDecl = cast<RecordDecl>(CurContext); |
| 5363 | QualType RecTy = Context.getTypeDeclType(Record); |
| 5364 | |
| 5365 | // Create a declaration for this anonymous struct. |
| 5366 | NamedDecl *Anon = |
| 5367 | FieldDecl::Create(Context, ParentDecl, DS.getBeginLoc(), DS.getBeginLoc(), |
| 5368 | /*IdentifierInfo=*/nullptr, RecTy, TInfo, |
| 5369 | /*BitWidth=*/nullptr, /*Mutable=*/false, |
| 5370 | /*InitStyle=*/ICIS_NoInit); |
| 5371 | Anon->setImplicit(); |
| 5372 | |
| 5373 | // Add the anonymous struct object to the current context. |
| 5374 | CurContext->addDecl(Anon); |
| 5375 | |
| 5376 | // Inject the members of the anonymous struct into the current |
| 5377 | // context and into the identifier resolver chain for name lookup |
| 5378 | // purposes. |
| 5379 | SmallVector<NamedDecl*, 2> Chain; |
| 5380 | Chain.push_back(Anon); |
| 5381 | |
| 5382 | RecordDecl *RecordDef = Record->getDefinition(); |
| 5383 | if (RequireCompleteSizedType(Anon->getLocation(), RecTy, |
| 5384 | diag::err_field_incomplete_or_sizeless) || |
| 5385 | InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef, |
| 5386 | AS_none, Chain)) { |
| 5387 | Anon->setInvalidDecl(); |
| 5388 | ParentDecl->setInvalidDecl(); |
| 5389 | } |
| 5390 | |
| 5391 | return Anon; |
| 5392 | } |
| 5393 | |
| 5394 | /// GetNameForDeclarator - Determine the full declaration name for the |
| 5395 | /// given Declarator. |
| 5396 | DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { |
| 5397 | return GetNameFromUnqualifiedId(D.getName()); |
| 5398 | } |
| 5399 | |
| 5400 | /// Retrieves the declaration name from a parsed unqualified-id. |
| 5401 | DeclarationNameInfo |
| 5402 | Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { |
| 5403 | DeclarationNameInfo NameInfo; |
| 5404 | NameInfo.setLoc(Name.StartLocation); |
| 5405 | |
| 5406 | switch (Name.getKind()) { |
| 5407 | |
| 5408 | case UnqualifiedIdKind::IK_ImplicitSelfParam: |
| 5409 | case UnqualifiedIdKind::IK_Identifier: |
| 5410 | NameInfo.setName(Name.Identifier); |
| 5411 | return NameInfo; |
| 5412 | |
| 5413 | case UnqualifiedIdKind::IK_DeductionGuideName: { |
| 5414 | // C++ [temp.deduct.guide]p3: |
| 5415 | // The simple-template-id shall name a class template specialization. |
| 5416 | // The template-name shall be the same identifier as the template-name |
| 5417 | // of the simple-template-id. |
| 5418 | // These together intend to imply that the template-name shall name a |
| 5419 | // class template. |
| 5420 | // FIXME: template<typename T> struct X {}; |
| 5421 | // template<typename T> using Y = X<T>; |
| 5422 | // Y(int) -> Y<int>; |
| 5423 | // satisfies these rules but does not name a class template. |
| 5424 | TemplateName TN = Name.TemplateName.get().get(); |
| 5425 | auto *Template = TN.getAsTemplateDecl(); |
| 5426 | if (!Template || !isa<ClassTemplateDecl>(Template)) { |
| 5427 | Diag(Name.StartLocation, |
| 5428 | diag::err_deduction_guide_name_not_class_template) |
| 5429 | << (int)getTemplateNameKindForDiagnostics(TN) << TN; |
| 5430 | if (Template) |
| 5431 | Diag(Template->getLocation(), diag::note_template_decl_here); |
| 5432 | return DeclarationNameInfo(); |
| 5433 | } |
| 5434 | |
| 5435 | NameInfo.setName( |
| 5436 | Context.DeclarationNames.getCXXDeductionGuideName(Template)); |
| 5437 | return NameInfo; |
| 5438 | } |
| 5439 | |
| 5440 | case UnqualifiedIdKind::IK_OperatorFunctionId: |
| 5441 | NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( |
| 5442 | Name.OperatorFunctionId.Operator)); |
| 5443 | NameInfo.setCXXOperatorNameRange(SourceRange( |
| 5444 | Name.OperatorFunctionId.SymbolLocations[0], Name.EndLocation)); |
| 5445 | return NameInfo; |
| 5446 | |
| 5447 | case UnqualifiedIdKind::IK_LiteralOperatorId: |
| 5448 | NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( |
| 5449 | Name.Identifier)); |
| 5450 | NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); |
| 5451 | return NameInfo; |
| 5452 | |
| 5453 | case UnqualifiedIdKind::IK_ConversionFunctionId: { |
| 5454 | TypeSourceInfo *TInfo; |
| 5455 | QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); |
| 5456 | if (Ty.isNull()) |
| 5457 | return DeclarationNameInfo(); |
| 5458 | NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( |
| 5459 | Context.getCanonicalType(Ty))); |
| 5460 | NameInfo.setNamedTypeInfo(TInfo); |
| 5461 | return NameInfo; |
| 5462 | } |
| 5463 | |
| 5464 | case UnqualifiedIdKind::IK_ConstructorName: { |
| 5465 | TypeSourceInfo *TInfo; |
| 5466 | QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); |
| 5467 | if (Ty.isNull()) |
| 5468 | return DeclarationNameInfo(); |
| 5469 | NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( |
| 5470 | Context.getCanonicalType(Ty))); |
| 5471 | NameInfo.setNamedTypeInfo(TInfo); |
| 5472 | return NameInfo; |
| 5473 | } |
| 5474 | |
| 5475 | case UnqualifiedIdKind::IK_ConstructorTemplateId: { |
| 5476 | // In well-formed code, we can only have a constructor |
| 5477 | // template-id that refers to the current context, so go there |
| 5478 | // to find the actual type being constructed. |
| 5479 | CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); |
| 5480 | if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) |
| 5481 | return DeclarationNameInfo(); |
| 5482 | |
| 5483 | // Determine the type of the class being constructed. |
| 5484 | QualType CurClassType = Context.getTypeDeclType(CurClass); |
| 5485 | |
| 5486 | // FIXME: Check two things: that the template-id names the same type as |
| 5487 | // CurClassType, and that the template-id does not occur when the name |
| 5488 | // was qualified. |
| 5489 | |
| 5490 | NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( |
| 5491 | Context.getCanonicalType(CurClassType))); |
| 5492 | // FIXME: should we retrieve TypeSourceInfo? |
| 5493 | NameInfo.setNamedTypeInfo(nullptr); |
| 5494 | return NameInfo; |
| 5495 | } |
| 5496 | |
| 5497 | case UnqualifiedIdKind::IK_DestructorName: { |
| 5498 | TypeSourceInfo *TInfo; |
| 5499 | QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); |
| 5500 | if (Ty.isNull()) |
| 5501 | return DeclarationNameInfo(); |
| 5502 | NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( |
| 5503 | Context.getCanonicalType(Ty))); |
| 5504 | NameInfo.setNamedTypeInfo(TInfo); |
| 5505 | return NameInfo; |
| 5506 | } |
| 5507 | |
| 5508 | case UnqualifiedIdKind::IK_TemplateId: { |
| 5509 | TemplateName TName = Name.TemplateId->Template.get(); |
| 5510 | SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; |
| 5511 | return Context.getNameForTemplate(TName, TNameLoc); |
| 5512 | } |
| 5513 | |
| 5514 | } // switch (Name.getKind()) |
| 5515 | |
| 5516 | llvm_unreachable("Unknown name kind")__builtin_unreachable(); |
| 5517 | } |
| 5518 | |
| 5519 | static QualType getCoreType(QualType Ty) { |
| 5520 | do { |
| 5521 | if (Ty->isPointerType() || Ty->isReferenceType()) |
| 5522 | Ty = Ty->getPointeeType(); |
| 5523 | else if (Ty->isArrayType()) |
| 5524 | Ty = Ty->castAsArrayTypeUnsafe()->getElementType(); |
| 5525 | else |
| 5526 | return Ty.withoutLocalFastQualifiers(); |
| 5527 | } while (true); |
| 5528 | } |
| 5529 | |
| 5530 | /// hasSimilarParameters - Determine whether the C++ functions Declaration |
| 5531 | /// and Definition have "nearly" matching parameters. This heuristic is |
| 5532 | /// used to improve diagnostics in the case where an out-of-line function |
| 5533 | /// definition doesn't match any declaration within the class or namespace. |
| 5534 | /// Also sets Params to the list of indices to the parameters that differ |
| 5535 | /// between the declaration and the definition. If hasSimilarParameters |
| 5536 | /// returns true and Params is empty, then all of the parameters match. |
| 5537 | static bool hasSimilarParameters(ASTContext &Context, |
| 5538 | FunctionDecl *Declaration, |
| 5539 | FunctionDecl *Definition, |
| 5540 | SmallVectorImpl<unsigned> &Params) { |
| 5541 | Params.clear(); |
| 5542 | if (Declaration->param_size() != Definition->param_size()) |
| 5543 | return false; |
| 5544 | for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { |
| 5545 | QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); |
| 5546 | QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); |
| 5547 | |
| 5548 | // The parameter types are identical |
| 5549 | if (Context.hasSameUnqualifiedType(DefParamTy, DeclParamTy)) |
| 5550 | continue; |
| 5551 | |
| 5552 | QualType DeclParamBaseTy = getCoreType(DeclParamTy); |
| 5553 | QualType DefParamBaseTy = getCoreType(DefParamTy); |
| 5554 | const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier(); |
| 5555 | const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier(); |
| 5556 | |
| 5557 | if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) || |
| 5558 | (DeclTyName && DeclTyName == DefTyName)) |
| 5559 | Params.push_back(Idx); |
| 5560 | else // The two parameters aren't even close |
| 5561 | return false; |
| 5562 | } |
| 5563 | |
| 5564 | return true; |
| 5565 | } |
| 5566 | |
| 5567 | /// NeedsRebuildingInCurrentInstantiation - Checks whether the given |
| 5568 | /// declarator needs to be rebuilt in the current instantiation. |
| 5569 | /// Any bits of declarator which appear before the name are valid for |
| 5570 | /// consideration here. That's specifically the type in the decl spec |
| 5571 | /// and the base type in any member-pointer chunks. |
| 5572 | static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, |
| 5573 | DeclarationName Name) { |
| 5574 | // The types we specifically need to rebuild are: |
| 5575 | // - typenames, typeofs, and decltypes |
| 5576 | // - types which will become injected class names |
| 5577 | // Of course, we also need to rebuild any type referencing such a |
| 5578 | // type. It's safest to just say "dependent", but we call out a |
| 5579 | // few cases here. |
| 5580 | |
| 5581 | DeclSpec &DS = D.getMutableDeclSpec(); |
| 5582 | switch (DS.getTypeSpecType()) { |
| 5583 | case DeclSpec::TST_typename: |
| 5584 | case DeclSpec::TST_typeofType: |
| 5585 | case DeclSpec::TST_underlyingType: |
| 5586 | case DeclSpec::TST_atomic: { |
| 5587 | // Grab the type from the parser. |
| 5588 | TypeSourceInfo *TSI = nullptr; |
| 5589 | QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); |
| 5590 | if (T.isNull() || !T->isInstantiationDependentType()) break; |
| 5591 | |
| 5592 | // Make sure there's a type source info. This isn't really much |
| 5593 | // of a waste; most dependent types should have type source info |
| 5594 | // attached already. |
| 5595 | if (!TSI) |
| 5596 | TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); |
| 5597 | |
| 5598 | // Rebuild the type in the current instantiation. |
| 5599 | TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); |
| 5600 | if (!TSI) return true; |
| 5601 | |
| 5602 | // Store the new type back in the decl spec. |
| 5603 | ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); |
| 5604 | DS.UpdateTypeRep(LocType); |
| 5605 | break; |
| 5606 | } |
| 5607 | |
| 5608 | case DeclSpec::TST_decltype: |
| 5609 | case DeclSpec::TST_typeofExpr: { |
| 5610 | Expr *E = DS.getRepAsExpr(); |
| 5611 | ExprResult Result = S.RebuildExprInCurrentInstantiation(E); |
| 5612 | if (Result.isInvalid()) return true; |
| 5613 | DS.UpdateExprRep(Result.get()); |
| 5614 | break; |
| 5615 | } |
| 5616 | |
| 5617 | default: |
| 5618 | // Nothing to do for these decl specs. |
| 5619 | break; |
| 5620 | } |
| 5621 | |
| 5622 | // It doesn't matter what order we do this in. |
| 5623 | for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { |
| 5624 | DeclaratorChunk &Chunk = D.getTypeObject(I); |
| 5625 | |
| 5626 | // The only type information in the declarator which can come |
| 5627 | // before the declaration name is the base type of a member |
| 5628 | // pointer. |
| 5629 | if (Chunk.Kind != DeclaratorChunk::MemberPointer) |
| 5630 | continue; |
| 5631 | |
| 5632 | // Rebuild the scope specifier in-place. |
| 5633 | CXXScopeSpec &SS = Chunk.Mem.Scope(); |
| 5634 | if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) |
| 5635 | return true; |
| 5636 | } |
| 5637 | |
| 5638 | return false; |
| 5639 | } |
| 5640 | |
| 5641 | void Sema::warnOnReservedIdentifier(const NamedDecl *D) { |
| 5642 | // Avoid warning twice on the same identifier, and don't warn on redeclaration |
| 5643 | // of system decl. |
| 5644 | if (D->getPreviousDecl() || D->isImplicit()) |
| 5645 | return; |
| 5646 | ReservedIdentifierStatus Status = D->isReserved(getLangOpts()); |
| 5647 | if (Status != ReservedIdentifierStatus::NotReserved && |
| 5648 | !Context.getSourceManager().isInSystemHeader(D->getLocation())) |
| 5649 | Diag(D->getLocation(), diag::warn_reserved_extern_symbol) |
| 5650 | << D << static_cast<int>(Status); |
| 5651 | } |
| 5652 | |
| 5653 | Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { |
| 5654 | D.setFunctionDefinitionKind(FunctionDefinitionKind::Declaration); |
| 5655 | Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg()); |
| 5656 | |
| 5657 | if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() && |
| 5658 | Dcl && Dcl->getDeclContext()->isFileContext()) |
| 5659 | Dcl->setTopLevelDeclInObjCContainer(); |
| 5660 | |
| 5661 | return Dcl; |
| 5662 | } |
| 5663 | |
| 5664 | /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13: |
| 5665 | /// If T is the name of a class, then each of the following shall have a |
| 5666 | /// name different from T: |
| 5667 | /// - every static data member of class T; |
| 5668 | /// - every member function of class T |
| 5669 | /// - every member of class T that is itself a type; |
| 5670 | /// \returns true if the declaration name violates these rules. |
| 5671 | bool Sema::DiagnoseClassNameShadow(DeclContext *DC, |
| 5672 | DeclarationNameInfo NameInfo) { |
| 5673 | DeclarationName Name = NameInfo.getName(); |
| 5674 | |
| 5675 | CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC); |
| 5676 | while (Record && Record->isAnonymousStructOrUnion()) |
| 5677 | Record = dyn_cast<CXXRecordDecl>(Record->getParent()); |
| 5678 | if (Record && Record->getIdentifier() && Record->getDeclName() == Name) { |
| 5679 | Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name; |
| 5680 | return true; |
| 5681 | } |
| 5682 | |
| 5683 | return false; |
| 5684 | } |
| 5685 | |
| 5686 | /// Diagnose a declaration whose declarator-id has the given |
| 5687 | /// nested-name-specifier. |
| 5688 | /// |
| 5689 | /// \param SS The nested-name-specifier of the declarator-id. |
| 5690 | /// |
| 5691 | /// \param DC The declaration context to which the nested-name-specifier |
| 5692 | /// resolves. |
| 5693 | /// |
| 5694 | /// \param Name The name of the entity being declared. |
| 5695 | /// |
| 5696 | /// \param Loc The location of the name of the entity being declared. |
| 5697 | /// |
| 5698 | /// \param IsTemplateId Whether the name is a (simple-)template-id, and thus |
| 5699 | /// we're declaring an explicit / partial specialization / instantiation. |
| 5700 | /// |
| 5701 | /// \returns true if we cannot safely recover from this error, false otherwise. |
| 5702 | bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC, |
| 5703 | DeclarationName Name, |
| 5704 | SourceLocation Loc, bool IsTemplateId) { |
| 5705 | DeclContext *Cur = CurContext; |
| 5706 | while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur)) |
| 5707 | Cur = Cur->getParent(); |
| 5708 | |
| 5709 | // If the user provided a superfluous scope specifier that refers back to the |
| 5710 | // class in which the entity is already declared, diagnose and ignore it. |
| 5711 | // |
| 5712 | // class X { |
| 5713 | // void X::f(); |
| 5714 | // }; |
| 5715 | // |
| 5716 | // Note, it was once ill-formed to give redundant qualification in all |
| 5717 | // contexts, but that rule was removed by DR482. |
| 5718 | if (Cur->Equals(DC)) { |
| 5719 | if (Cur->isRecord()) { |
| 5720 | Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification |
| 5721 | : diag::err_member_extra_qualification) |
| 5722 | << Name << FixItHint::CreateRemoval(SS.getRange()); |
| 5723 | SS.clear(); |
| 5724 | } else { |
| 5725 | Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name; |
| 5726 | } |
| 5727 | return false; |
| 5728 | } |
| 5729 | |
| 5730 | // Check whether the qualifying scope encloses the scope of the original |
| 5731 | // declaration. For a template-id, we perform the checks in |
| 5732 | // CheckTemplateSpecializationScope. |
| 5733 | if (!Cur->Encloses(DC) && !IsTemplateId) { |
| 5734 | if (Cur->isRecord()) |
| 5735 | Diag(Loc, diag::err_member_qualification) |
| 5736 | << Name << SS.getRange(); |
| 5737 | else if (isa<TranslationUnitDecl>(DC)) |
| 5738 | Diag(Loc, diag::err_invalid_declarator_global_scope) |
| 5739 | << Name << SS.getRange(); |
| 5740 | else if (isa<FunctionDecl>(Cur)) |
| 5741 | Diag(Loc, diag::err_invalid_declarator_in_function) |
| 5742 | << Name << SS.getRange(); |
| 5743 | else if (isa<BlockDecl>(Cur)) |
| 5744 | Diag(Loc, diag::err_invalid_declarator_in_block) |
| 5745 | << Name << SS.getRange(); |
| 5746 | else |
| 5747 | Diag(Loc, diag::err_invalid_declarator_scope) |
| 5748 | << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange(); |
| 5749 | |
| 5750 | return true; |
| 5751 | } |
| 5752 | |
| 5753 | if (Cur->isRecord()) { |
| 5754 | // Cannot qualify members within a class. |
| 5755 | Diag(Loc, diag::err_member_qualification) |
| 5756 | << Name << SS.getRange(); |
| 5757 | SS.clear(); |
| 5758 | |
| 5759 | // C++ constructors and destructors with incorrect scopes can break |
| 5760 | // our AST invariants by having the wrong underlying types. If |
| 5761 | // that's the case, then drop this declaration entirely. |
| 5762 | if ((Name.getNameKind() == DeclarationName::CXXConstructorName || |
| 5763 | Name.getNameKind() == DeclarationName::CXXDestructorName) && |
| 5764 | !Context.hasSameType(Name.getCXXNameType(), |
| 5765 | Context.getTypeDeclType(cast<CXXRecordDecl>(Cur)))) |
| 5766 | return true; |
| 5767 | |
| 5768 | return false; |
| 5769 | } |
| 5770 | |
| 5771 | // C++11 [dcl.meaning]p1: |
| 5772 | // [...] "The nested-name-specifier of the qualified declarator-id shall |
| 5773 | // not begin with a decltype-specifer" |
| 5774 | NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data()); |
| 5775 | while (SpecLoc.getPrefix()) |
| 5776 | SpecLoc = SpecLoc.getPrefix(); |
| 5777 | if (dyn_cast_or_null<DecltypeType>( |
| 5778 | SpecLoc.getNestedNameSpecifier()->getAsType())) |
| 5779 | Diag(Loc, diag::err_decltype_in_declarator) |
| 5780 | << SpecLoc.getTypeLoc().getSourceRange(); |
| 5781 | |
| 5782 | return false; |
| 5783 | } |
| 5784 | |
| 5785 | NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D, |
| 5786 | MultiTemplateParamsArg TemplateParamLists) { |
| 5787 | // TODO: consider using NameInfo for diagnostic. |
| 5788 | DeclarationNameInfo NameInfo = GetNameForDeclarator(D); |
| 5789 | DeclarationName Name = NameInfo.getName(); |
| 5790 | |
| 5791 | // All of these full declarators require an identifier. If it doesn't have |
| 5792 | // one, the ParsedFreeStandingDeclSpec action should be used. |
| 5793 | if (D.isDecompositionDeclarator()) { |
| 5794 | return ActOnDecompositionDeclarator(S, D, TemplateParamLists); |
| 5795 | } else if (!Name) { |
| 5796 | if (!D.isInvalidType()) // Reject this if we think it is valid. |
| 5797 | Diag(D.getDeclSpec().getBeginLoc(), diag::err_declarator_need_ident) |
| 5798 | << D.getDeclSpec().getSourceRange() << D.getSourceRange(); |
| 5799 | return nullptr; |
| 5800 | } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) |
| 5801 | return nullptr; |
| 5802 | |
| 5803 | // The scope passed in may not be a decl scope. Zip up the scope tree until |
| 5804 | // we find one that is. |
| 5805 | while ((S->getFlags() & Scope::DeclScope) == 0 || |
| 5806 | (S->getFlags() & Scope::TemplateParamScope) != 0) |
| 5807 | S = S->getParent(); |
| 5808 | |
| 5809 | DeclContext *DC = CurContext; |
| 5810 | if (D.getCXXScopeSpec().isInvalid()) |
| 5811 | D.setInvalidType(); |
| 5812 | else if (D.getCXXScopeSpec().isSet()) { |
| 5813 | if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), |
| 5814 | UPPC_DeclarationQualifier)) |
| 5815 | return nullptr; |
| 5816 | |
| 5817 | bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); |
| 5818 | DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); |
| 5819 | if (!DC || isa<EnumDecl>(DC)) { |
| 5820 | // If we could not compute the declaration context, it's because the |
| 5821 | // declaration context is dependent but does not refer to a class, |
| 5822 | // class template, or class template partial specialization. Complain |
| 5823 | // and return early, to avoid the coming semantic disaster. |
| 5824 | Diag(D.getIdentifierLoc(), |
| 5825 | diag::err_template_qualified_declarator_no_match) |
| 5826 | << D.getCXXScopeSpec().getScopeRep() |
| 5827 | << D.getCXXScopeSpec().getRange(); |
| 5828 | return nullptr; |
| 5829 | } |
| 5830 | bool IsDependentContext = DC->isDependentContext(); |
| 5831 | |
| 5832 | if (!IsDependentContext && |
| 5833 | RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) |
| 5834 | return nullptr; |
| 5835 | |
| 5836 | // If a class is incomplete, do not parse entities inside it. |
| 5837 | if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { |
| 5838 | Diag(D.getIdentifierLoc(), |
| 5839 | diag::err_member_def_undefined_record) |
| 5840 | << Name << DC << D.getCXXScopeSpec().getRange(); |
| 5841 | return nullptr; |
| 5842 | } |
| 5843 | if (!D.getDeclSpec().isFriendSpecified()) { |
| 5844 | if (diagnoseQualifiedDeclaration( |
| 5845 | D.getCXXScopeSpec(), DC, Name, D.getIdentifierLoc(), |
| 5846 | D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId)) { |
| 5847 | if (DC->isRecord()) |
| 5848 | return nullptr; |
| 5849 | |
| 5850 | D.setInvalidType(); |
| 5851 | } |
| 5852 | } |
| 5853 | |
| 5854 | // Check whether we need to rebuild the type of the given |
| 5855 | // declaration in the current instantiation. |
| 5856 | if (EnteringContext && IsDependentContext && |
| 5857 | TemplateParamLists.size() != 0) { |
| 5858 | ContextRAII SavedContext(*this, DC); |
| 5859 | if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) |
| 5860 | D.setInvalidType(); |
| 5861 | } |
| 5862 | } |
| 5863 | |
| 5864 | TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); |
| 5865 | QualType R = TInfo->getType(); |
| 5866 | |
| 5867 | if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, |
| 5868 | UPPC_DeclarationType)) |
| 5869 | D.setInvalidType(); |
| 5870 | |
| 5871 | LookupResult Previous(*this, NameInfo, LookupOrdinaryName, |
| 5872 | forRedeclarationInCurContext()); |
| 5873 | |
| 5874 | // See if this is a redefinition of a variable in the same scope. |
| 5875 | if (!D.getCXXScopeSpec().isSet()) { |
| 5876 | bool IsLinkageLookup = false; |
| 5877 | bool CreateBuiltins = false; |
| 5878 | |
| 5879 | // If the declaration we're planning to build will be a function |
| 5880 | // or object with linkage, then look for another declaration with |
| 5881 | // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). |
| 5882 | // |
| 5883 | // If the declaration we're planning to build will be declared with |
| 5884 | // external linkage in the translation unit, create any builtin with |
| 5885 | // the same name. |
| 5886 | if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) |
| 5887 | /* Do nothing*/; |
| 5888 | else if (CurContext->isFunctionOrMethod() && |
| 5889 | (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern || |
| 5890 | R->isFunctionType())) { |
| 5891 | IsLinkageLookup = true; |
| 5892 | CreateBuiltins = |
| 5893 | CurContext->getEnclosingNamespaceContext()->isTranslationUnit(); |
| 5894 | } else if (CurContext->getRedeclContext()->isTranslationUnit() && |
| 5895 | D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) |
| 5896 | CreateBuiltins = true; |
| 5897 | |
| 5898 | if (IsLinkageLookup) { |
| 5899 | Previous.clear(LookupRedeclarationWithLinkage); |
| 5900 | Previous.setRedeclarationKind(ForExternalRedeclaration); |
| 5901 | } |
| 5902 | |
| 5903 | LookupName(Previous, S, CreateBuiltins); |
| 5904 | } else { // Something like "int foo::x;" |
| 5905 | LookupQualifiedName(Previous, DC); |
| 5906 | |
| 5907 | // C++ [dcl.meaning]p1: |
| 5908 | // When the declarator-id is qualified, the declaration shall refer to a |
| 5909 | // previously declared member of the class or namespace to which the |
| 5910 | // qualifier refers (or, in the case of a namespace, of an element of the |
| 5911 | // inline namespace set of that namespace (7.3.1)) or to a specialization |
| 5912 | // thereof; [...] |
| 5913 | // |
| 5914 | // Note that we already checked the context above, and that we do not have |
| 5915 | // enough information to make sure that Previous contains the declaration |
| 5916 | // we want to match. For example, given: |
| 5917 | // |
| 5918 | // class X { |
| 5919 | // void f(); |
| 5920 | // void f(float); |
| 5921 | // }; |
| 5922 | // |
| 5923 | // void X::f(int) { } // ill-formed |
| 5924 | // |
| 5925 | // In this case, Previous will point to the overload set |
| 5926 | // containing the two f's declared in X, but neither of them |
| 5927 | // matches. |
| 5928 | |
| 5929 | // C++ [dcl.meaning]p1: |
| 5930 | // [...] the member shall not merely have been introduced by a |
| 5931 | // using-declaration in the scope of the class or namespace nominated by |
| 5932 | // the nested-name-specifier of the declarator-id. |
| 5933 | RemoveUsingDecls(Previous); |
| 5934 | } |
| 5935 | |
| 5936 | if (Previous.isSingleResult() && |
| 5937 | Previous.getFoundDecl()->isTemplateParameter()) { |
| 5938 | // Maybe we will complain about the shadowed template parameter. |
| 5939 | if (!D.isInvalidType()) |
| 5940 | DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), |
| 5941 | Previous.getFoundDecl()); |
| 5942 | |
| 5943 | // Just pretend that we didn't see the previous declaration. |
| 5944 | Previous.clear(); |
| 5945 | } |
| 5946 | |
| 5947 | if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo)) |
| 5948 | // Forget that the previous declaration is the injected-class-name. |
| 5949 | Previous.clear(); |
| 5950 | |
| 5951 | // In C++, the previous declaration we find might be a tag type |
| 5952 | // (class or enum). In this case, the new declaration will hide the |
| 5953 | // tag type. Note that this applies to functions, function templates, and |
| 5954 | // variables, but not to typedefs (C++ [dcl.typedef]p4) or variable templates. |
| 5955 | if (Previous.isSingleTagDecl() && |
| 5956 | D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef && |
| 5957 | (TemplateParamLists.size() == 0 || R->isFunctionType())) |
| 5958 | Previous.clear(); |
| 5959 | |
| 5960 | // Check that there are no default arguments other than in the parameters |
| 5961 | // of a function declaration (C++ only). |
| 5962 | if (getLangOpts().CPlusPlus) |
| 5963 | CheckExtraCXXDefaultArguments(D); |
| 5964 | |
| 5965 | NamedDecl *New; |
| 5966 | |
| 5967 | bool AddToScope = true; |
| 5968 | if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { |
| 5969 | if (TemplateParamLists.size()) { |
| 5970 | Diag(D.getIdentifierLoc(), diag::err_template_typedef); |
| 5971 | return nullptr; |
| 5972 | } |
| 5973 | |
| 5974 | New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous); |
| 5975 | } else if (R->isFunctionType()) { |
| 5976 | New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous, |
| 5977 | TemplateParamLists, |
| 5978 | AddToScope); |
| 5979 | } else { |
| 5980 | New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists, |
| 5981 | AddToScope); |
| 5982 | } |
| 5983 | |
| 5984 | if (!New) |
| 5985 | return nullptr; |
| 5986 | |
| 5987 | // If this has an identifier and is not a function template specialization, |
| 5988 | // add it to the scope stack. |
| 5989 | if (New->getDeclName() && AddToScope) |
| 5990 | PushOnScopeChains(New, S); |
| 5991 | |
| 5992 | if (isInOpenMPDeclareTargetContext()) |
| 5993 | checkDeclIsAllowedInOpenMPTarget(nullptr, New); |
| 5994 | |
| 5995 | return New; |
| 5996 | } |
| 5997 | |
| 5998 | /// Helper method to turn variable array types into constant array |
| 5999 | /// types in certain situations which would otherwise be errors (for |
| 6000 | /// GCC compatibility). |
| 6001 | static QualType TryToFixInvalidVariablyModifiedType(QualType T, |
| 6002 | ASTContext &Context, |
| 6003 | bool &SizeIsNegative, |
| 6004 | llvm::APSInt &Oversized) { |
| 6005 | // This method tries to turn a variable array into a constant |
| 6006 | // array even when the size isn't an ICE. This is necessary |
| 6007 | // for compatibility with code that depends on gcc's buggy |
| 6008 | // constant expression folding, like struct {char x[(int)(char*)2];} |
| 6009 | SizeIsNegative = false; |
| 6010 | Oversized = 0; |
| 6011 | |
| 6012 | if (T->isDependentType()) |
| 6013 | return QualType(); |
| 6014 | |
| 6015 | QualifierCollector Qs; |
| 6016 | const Type *Ty = Qs.strip(T); |
| 6017 | |
| 6018 | if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { |
| 6019 | QualType Pointee = PTy->getPointeeType(); |
| 6020 | QualType FixedType = |
| 6021 | TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, |
| 6022 | Oversized); |
| 6023 | if (FixedType.isNull()) return FixedType; |
| 6024 | FixedType = Context.getPointerType(FixedType); |
| 6025 | return Qs.apply(Context, FixedType); |
| 6026 | } |
| 6027 | if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { |
| 6028 | QualType Inner = PTy->getInnerType(); |