1 //===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements semantic analysis for declarations. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "clang/Sema/SemaInternal.h" 15 #include "TypeLocBuilder.h" 16 #include "clang/AST/ASTConsumer.h" 17 #include "clang/AST/ASTContext.h" 18 #include "clang/AST/CXXInheritance.h" 19 #include "clang/AST/CharUnits.h" 20 #include "clang/AST/CommentDiagnostic.h" 21 #include "clang/AST/DeclCXX.h" 22 #include "clang/AST/DeclObjC.h" 23 #include "clang/AST/DeclTemplate.h" 24 #include "clang/AST/EvaluatedExprVisitor.h" 25 #include "clang/AST/ExprCXX.h" 26 #include "clang/AST/StmtCXX.h" 27 #include "clang/Basic/PartialDiagnostic.h" 28 #include "clang/Basic/SourceManager.h" 29 #include "clang/Basic/TargetInfo.h" 30 #include "clang/Lex/HeaderSearch.h" // FIXME: Sema shouldn't depend on Lex 31 #include "clang/Lex/ModuleLoader.h" // FIXME: Sema shouldn't depend on Lex 32 #include "clang/Lex/Preprocessor.h" // FIXME: Sema shouldn't depend on Lex 33 #include "clang/Parse/ParseDiagnostic.h" 34 #include "clang/Sema/CXXFieldCollector.h" 35 #include "clang/Sema/DeclSpec.h" 36 #include "clang/Sema/DelayedDiagnostic.h" 37 #include "clang/Sema/Initialization.h" 38 #include "clang/Sema/Lookup.h" 39 #include "clang/Sema/ParsedTemplate.h" 40 #include "clang/Sema/Scope.h" 41 #include "clang/Sema/ScopeInfo.h" 42 #include "llvm/ADT/SmallString.h" 43 #include "llvm/ADT/Triple.h" 44 #include <algorithm> 45 #include <cstring> 46 #include <functional> 47 using namespace clang; 48 using namespace sema; 49 50 Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType) { 51 if (OwnedType) { 52 Decl *Group[2] = { OwnedType, Ptr }; 53 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, 2)); 54 } 55 56 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 57 } 58 59 namespace { 60 61 class TypeNameValidatorCCC : public CorrectionCandidateCallback { 62 public: 63 TypeNameValidatorCCC(bool AllowInvalid, bool WantClass=false) 64 : AllowInvalidDecl(AllowInvalid), WantClassName(WantClass) { 65 WantExpressionKeywords = false; 66 WantCXXNamedCasts = false; 67 WantRemainingKeywords = false; 68 } 69 70 virtual bool ValidateCandidate(const TypoCorrection &candidate) { 71 if (NamedDecl *ND = candidate.getCorrectionDecl()) 72 return (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND)) && 73 (AllowInvalidDecl || !ND->isInvalidDecl()); 74 else 75 return !WantClassName && candidate.isKeyword(); 76 } 77 78 private: 79 bool AllowInvalidDecl; 80 bool WantClassName; 81 }; 82 83 } 84 85 /// \brief Determine whether the token kind starts a simple-type-specifier. 86 bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const { 87 switch (Kind) { 88 // FIXME: Take into account the current language when deciding whether a 89 // token kind is a valid type specifier 90 case tok::kw_short: 91 case tok::kw_long: 92 case tok::kw___int64: 93 case tok::kw___int128: 94 case tok::kw_signed: 95 case tok::kw_unsigned: 96 case tok::kw_void: 97 case tok::kw_char: 98 case tok::kw_int: 99 case tok::kw_half: 100 case tok::kw_float: 101 case tok::kw_double: 102 case tok::kw_wchar_t: 103 case tok::kw_bool: 104 case tok::kw___underlying_type: 105 return true; 106 107 case tok::annot_typename: 108 case tok::kw_char16_t: 109 case tok::kw_char32_t: 110 case tok::kw_typeof: 111 case tok::kw_decltype: 112 return getLangOpts().CPlusPlus; 113 114 default: 115 break; 116 } 117 118 return false; 119 } 120 121 /// \brief If the identifier refers to a type name within this scope, 122 /// return the declaration of that type. 123 /// 124 /// This routine performs ordinary name lookup of the identifier II 125 /// within the given scope, with optional C++ scope specifier SS, to 126 /// determine whether the name refers to a type. If so, returns an 127 /// opaque pointer (actually a QualType) corresponding to that 128 /// type. Otherwise, returns NULL. 129 /// 130 /// If name lookup results in an ambiguity, this routine will complain 131 /// and then return NULL. 132 ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc, 133 Scope *S, CXXScopeSpec *SS, 134 bool isClassName, bool HasTrailingDot, 135 ParsedType ObjectTypePtr, 136 bool IsCtorOrDtorName, 137 bool WantNontrivialTypeSourceInfo, 138 IdentifierInfo **CorrectedII) { 139 // Determine where we will perform name lookup. 140 DeclContext *LookupCtx = 0; 141 if (ObjectTypePtr) { 142 QualType ObjectType = ObjectTypePtr.get(); 143 if (ObjectType->isRecordType()) 144 LookupCtx = computeDeclContext(ObjectType); 145 } else if (SS && SS->isNotEmpty()) { 146 LookupCtx = computeDeclContext(*SS, false); 147 148 if (!LookupCtx) { 149 if (isDependentScopeSpecifier(*SS)) { 150 // C++ [temp.res]p3: 151 // A qualified-id that refers to a type and in which the 152 // nested-name-specifier depends on a template-parameter (14.6.2) 153 // shall be prefixed by the keyword typename to indicate that the 154 // qualified-id denotes a type, forming an 155 // elaborated-type-specifier (7.1.5.3). 156 // 157 // We therefore do not perform any name lookup if the result would 158 // refer to a member of an unknown specialization. 159 if (!isClassName && !IsCtorOrDtorName) 160 return ParsedType(); 161 162 // We know from the grammar that this name refers to a type, 163 // so build a dependent node to describe the type. 164 if (WantNontrivialTypeSourceInfo) 165 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); 166 167 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); 168 QualType T = 169 CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, 170 II, NameLoc); 171 172 return ParsedType::make(T); 173 } 174 175 return ParsedType(); 176 } 177 178 if (!LookupCtx->isDependentContext() && 179 RequireCompleteDeclContext(*SS, LookupCtx)) 180 return ParsedType(); 181 } 182 183 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 184 // lookup for class-names. 185 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 186 LookupOrdinaryName; 187 LookupResult Result(*this, &II, NameLoc, Kind); 188 if (LookupCtx) { 189 // Perform "qualified" name lookup into the declaration context we 190 // computed, which is either the type of the base of a member access 191 // expression or the declaration context associated with a prior 192 // nested-name-specifier. 193 LookupQualifiedName(Result, LookupCtx); 194 195 if (ObjectTypePtr && Result.empty()) { 196 // C++ [basic.lookup.classref]p3: 197 // If the unqualified-id is ~type-name, the type-name is looked up 198 // in the context of the entire postfix-expression. If the type T of 199 // the object expression is of a class type C, the type-name is also 200 // looked up in the scope of class C. At least one of the lookups shall 201 // find a name that refers to (possibly cv-qualified) T. 202 LookupName(Result, S); 203 } 204 } else { 205 // Perform unqualified name lookup. 206 LookupName(Result, S); 207 } 208 209 NamedDecl *IIDecl = 0; 210 switch (Result.getResultKind()) { 211 case LookupResult::NotFound: 212 case LookupResult::NotFoundInCurrentInstantiation: 213 if (CorrectedII) { 214 TypeNameValidatorCCC Validator(true, isClassName); 215 TypoCorrection Correction = CorrectTypo(Result.getLookupNameInfo(), 216 Kind, S, SS, Validator); 217 IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo(); 218 TemplateTy Template; 219 bool MemberOfUnknownSpecialization; 220 UnqualifiedId TemplateName; 221 TemplateName.setIdentifier(NewII, NameLoc); 222 NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier(); 223 CXXScopeSpec NewSS, *NewSSPtr = SS; 224 if (SS && NNS) { 225 NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc)); 226 NewSSPtr = &NewSS; 227 } 228 if (Correction && (NNS || NewII != &II) && 229 // Ignore a correction to a template type as the to-be-corrected 230 // identifier is not a template (typo correction for template names 231 // is handled elsewhere). 232 !(getLangOpts().CPlusPlus && NewSSPtr && 233 isTemplateName(S, *NewSSPtr, false, TemplateName, ParsedType(), 234 false, Template, MemberOfUnknownSpecialization))) { 235 ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr, 236 isClassName, HasTrailingDot, ObjectTypePtr, 237 IsCtorOrDtorName, 238 WantNontrivialTypeSourceInfo); 239 if (Ty) { 240 std::string CorrectedStr(Correction.getAsString(getLangOpts())); 241 std::string CorrectedQuotedStr( 242 Correction.getQuoted(getLangOpts())); 243 Diag(NameLoc, diag::err_unknown_type_or_class_name_suggest) 244 << Result.getLookupName() << CorrectedQuotedStr << isClassName 245 << FixItHint::CreateReplacement(SourceRange(NameLoc), 246 CorrectedStr); 247 if (NamedDecl *FirstDecl = Correction.getCorrectionDecl()) 248 Diag(FirstDecl->getLocation(), diag::note_previous_decl) 249 << CorrectedQuotedStr; 250 251 if (SS && NNS) 252 SS->MakeTrivial(Context, NNS, SourceRange(NameLoc)); 253 *CorrectedII = NewII; 254 return Ty; 255 } 256 } 257 } 258 // If typo correction failed or was not performed, fall through 259 case LookupResult::FoundOverloaded: 260 case LookupResult::FoundUnresolvedValue: 261 Result.suppressDiagnostics(); 262 return ParsedType(); 263 264 case LookupResult::Ambiguous: 265 // Recover from type-hiding ambiguities by hiding the type. We'll 266 // do the lookup again when looking for an object, and we can 267 // diagnose the error then. If we don't do this, then the error 268 // about hiding the type will be immediately followed by an error 269 // that only makes sense if the identifier was treated like a type. 270 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 271 Result.suppressDiagnostics(); 272 return ParsedType(); 273 } 274 275 // Look to see if we have a type anywhere in the list of results. 276 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 277 Res != ResEnd; ++Res) { 278 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 279 if (!IIDecl || 280 (*Res)->getLocation().getRawEncoding() < 281 IIDecl->getLocation().getRawEncoding()) 282 IIDecl = *Res; 283 } 284 } 285 286 if (!IIDecl) { 287 // None of the entities we found is a type, so there is no way 288 // to even assume that the result is a type. In this case, don't 289 // complain about the ambiguity. The parser will either try to 290 // perform this lookup again (e.g., as an object name), which 291 // will produce the ambiguity, or will complain that it expected 292 // a type name. 293 Result.suppressDiagnostics(); 294 return ParsedType(); 295 } 296 297 // We found a type within the ambiguous lookup; diagnose the 298 // ambiguity and then return that type. This might be the right 299 // answer, or it might not be, but it suppresses any attempt to 300 // perform the name lookup again. 301 break; 302 303 case LookupResult::Found: 304 IIDecl = Result.getFoundDecl(); 305 break; 306 } 307 308 assert(IIDecl && "Didn't find decl"); 309 310 QualType T; 311 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 312 DiagnoseUseOfDecl(IIDecl, NameLoc); 313 314 if (T.isNull()) 315 T = Context.getTypeDeclType(TD); 316 317 // NOTE: avoid constructing an ElaboratedType(Loc) if this is a 318 // constructor or destructor name (in such a case, the scope specifier 319 // will be attached to the enclosing Expr or Decl node). 320 if (SS && SS->isNotEmpty() && !IsCtorOrDtorName) { 321 if (WantNontrivialTypeSourceInfo) { 322 // Construct a type with type-source information. 323 TypeLocBuilder Builder; 324 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 325 326 T = getElaboratedType(ETK_None, *SS, T); 327 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 328 ElabTL.setElaboratedKeywordLoc(SourceLocation()); 329 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); 330 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 331 } else { 332 T = getElaboratedType(ETK_None, *SS, T); 333 } 334 } 335 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 336 (void)DiagnoseUseOfDecl(IDecl, NameLoc); 337 if (!HasTrailingDot) 338 T = Context.getObjCInterfaceType(IDecl); 339 } 340 341 if (T.isNull()) { 342 // If it's not plausibly a type, suppress diagnostics. 343 Result.suppressDiagnostics(); 344 return ParsedType(); 345 } 346 return ParsedType::make(T); 347 } 348 349 /// isTagName() - This method is called *for error recovery purposes only* 350 /// to determine if the specified name is a valid tag name ("struct foo"). If 351 /// so, this returns the TST for the tag corresponding to it (TST_enum, 352 /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose 353 /// cases in C where the user forgot to specify the tag. 354 DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 355 // Do a tag name lookup in this scope. 356 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 357 LookupName(R, S, false); 358 R.suppressDiagnostics(); 359 if (R.getResultKind() == LookupResult::Found) 360 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 361 switch (TD->getTagKind()) { 362 case TTK_Struct: return DeclSpec::TST_struct; 363 case TTK_Interface: return DeclSpec::TST_interface; 364 case TTK_Union: return DeclSpec::TST_union; 365 case TTK_Class: return DeclSpec::TST_class; 366 case TTK_Enum: return DeclSpec::TST_enum; 367 } 368 } 369 370 return DeclSpec::TST_unspecified; 371 } 372 373 /// isMicrosoftMissingTypename - In Microsoft mode, within class scope, 374 /// if a CXXScopeSpec's type is equal to the type of one of the base classes 375 /// then downgrade the missing typename error to a warning. 376 /// This is needed for MSVC compatibility; Example: 377 /// @code 378 /// template<class T> class A { 379 /// public: 380 /// typedef int TYPE; 381 /// }; 382 /// template<class T> class B : public A<T> { 383 /// public: 384 /// A<T>::TYPE a; // no typename required because A<T> is a base class. 385 /// }; 386 /// @endcode 387 bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) { 388 if (CurContext->isRecord()) { 389 const Type *Ty = SS->getScopeRep()->getAsType(); 390 391 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext); 392 for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), 393 BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) 394 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base->getType())) 395 return true; 396 return S->isFunctionPrototypeScope(); 397 } 398 return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope(); 399 } 400 401 bool Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II, 402 SourceLocation IILoc, 403 Scope *S, 404 CXXScopeSpec *SS, 405 ParsedType &SuggestedType) { 406 // We don't have anything to suggest (yet). 407 SuggestedType = ParsedType(); 408 409 // There may have been a typo in the name of the type. Look up typo 410 // results, in case we have something that we can suggest. 411 TypeNameValidatorCCC Validator(false); 412 if (TypoCorrection Corrected = CorrectTypo(DeclarationNameInfo(II, IILoc), 413 LookupOrdinaryName, S, SS, 414 Validator)) { 415 std::string CorrectedStr(Corrected.getAsString(getLangOpts())); 416 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); 417 418 if (Corrected.isKeyword()) { 419 // We corrected to a keyword. 420 IdentifierInfo *NewII = Corrected.getCorrectionAsIdentifierInfo(); 421 if (!isSimpleTypeSpecifier(NewII->getTokenID())) 422 CorrectedQuotedStr = "the keyword " + CorrectedQuotedStr; 423 Diag(IILoc, diag::err_unknown_typename_suggest) 424 << II << CorrectedQuotedStr 425 << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), 426 CorrectedStr); 427 II = NewII; 428 } else { 429 NamedDecl *Result = Corrected.getCorrectionDecl(); 430 // We found a similarly-named type or interface; suggest that. 431 if (!SS || !SS->isSet()) { 432 Diag(IILoc, diag::err_unknown_typename_suggest) 433 << II << CorrectedQuotedStr 434 << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), 435 CorrectedStr); 436 } else if (DeclContext *DC = computeDeclContext(*SS, false)) { 437 bool droppedSpecifier = Corrected.WillReplaceSpecifier() && 438 II->getName().equals(CorrectedStr); 439 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 440 << II << DC << droppedSpecifier << CorrectedQuotedStr 441 << SS->getRange() 442 << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), 443 CorrectedStr); 444 } 445 else { 446 llvm_unreachable("could not have corrected a typo here"); 447 } 448 449 Diag(Result->getLocation(), diag::note_previous_decl) 450 << CorrectedQuotedStr; 451 452 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, 453 false, false, ParsedType(), 454 /*IsCtorOrDtorName=*/false, 455 /*NonTrivialTypeSourceInfo=*/true); 456 } 457 return true; 458 } 459 460 if (getLangOpts().CPlusPlus) { 461 // See if II is a class template that the user forgot to pass arguments to. 462 UnqualifiedId Name; 463 Name.setIdentifier(II, IILoc); 464 CXXScopeSpec EmptySS; 465 TemplateTy TemplateResult; 466 bool MemberOfUnknownSpecialization; 467 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 468 Name, ParsedType(), true, TemplateResult, 469 MemberOfUnknownSpecialization) == TNK_Type_template) { 470 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 471 Diag(IILoc, diag::err_template_missing_args) << TplName; 472 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 473 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 474 << TplDecl->getTemplateParameters()->getSourceRange(); 475 } 476 return true; 477 } 478 } 479 480 // FIXME: Should we move the logic that tries to recover from a missing tag 481 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 482 483 if (!SS || (!SS->isSet() && !SS->isInvalid())) 484 Diag(IILoc, diag::err_unknown_typename) << II; 485 else if (DeclContext *DC = computeDeclContext(*SS, false)) 486 Diag(IILoc, diag::err_typename_nested_not_found) 487 << II << DC << SS->getRange(); 488 else if (isDependentScopeSpecifier(*SS)) { 489 unsigned DiagID = diag::err_typename_missing; 490 if (getLangOpts().MicrosoftMode && isMicrosoftMissingTypename(SS, S)) 491 DiagID = diag::warn_typename_missing; 492 493 Diag(SS->getRange().getBegin(), DiagID) 494 << (NestedNameSpecifier *)SS->getScopeRep() << II->getName() 495 << SourceRange(SS->getRange().getBegin(), IILoc) 496 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 497 SuggestedType = ActOnTypenameType(S, SourceLocation(), 498 *SS, *II, IILoc).get(); 499 } else { 500 assert(SS && SS->isInvalid() && 501 "Invalid scope specifier has already been diagnosed"); 502 } 503 504 return true; 505 } 506 507 /// \brief Determine whether the given result set contains either a type name 508 /// or 509 static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) { 510 bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus && 511 NextToken.is(tok::less); 512 513 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) { 514 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I)) 515 return true; 516 517 if (CheckTemplate && isa<TemplateDecl>(*I)) 518 return true; 519 } 520 521 return false; 522 } 523 524 static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result, 525 Scope *S, CXXScopeSpec &SS, 526 IdentifierInfo *&Name, 527 SourceLocation NameLoc) { 528 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName); 529 SemaRef.LookupParsedName(R, S, &SS); 530 if (TagDecl *Tag = R.getAsSingle<TagDecl>()) { 531 const char *TagName = 0; 532 const char *FixItTagName = 0; 533 switch (Tag->getTagKind()) { 534 case TTK_Class: 535 TagName = "class"; 536 FixItTagName = "class "; 537 break; 538 539 case TTK_Enum: 540 TagName = "enum"; 541 FixItTagName = "enum "; 542 break; 543 544 case TTK_Struct: 545 TagName = "struct"; 546 FixItTagName = "struct "; 547 break; 548 549 case TTK_Interface: 550 TagName = "__interface"; 551 FixItTagName = "__interface "; 552 break; 553 554 case TTK_Union: 555 TagName = "union"; 556 FixItTagName = "union "; 557 break; 558 } 559 560 SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag) 561 << Name << TagName << SemaRef.getLangOpts().CPlusPlus 562 << FixItHint::CreateInsertion(NameLoc, FixItTagName); 563 564 for (LookupResult::iterator I = Result.begin(), IEnd = Result.end(); 565 I != IEnd; ++I) 566 SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type) 567 << Name << TagName; 568 569 // Replace lookup results with just the tag decl. 570 Result.clear(Sema::LookupTagName); 571 SemaRef.LookupParsedName(Result, S, &SS); 572 return true; 573 } 574 575 return false; 576 } 577 578 /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier. 579 static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS, 580 QualType T, SourceLocation NameLoc) { 581 ASTContext &Context = S.Context; 582 583 TypeLocBuilder Builder; 584 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 585 586 T = S.getElaboratedType(ETK_None, SS, T); 587 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 588 ElabTL.setElaboratedKeywordLoc(SourceLocation()); 589 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context)); 590 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 591 } 592 593 Sema::NameClassification Sema::ClassifyName(Scope *S, 594 CXXScopeSpec &SS, 595 IdentifierInfo *&Name, 596 SourceLocation NameLoc, 597 const Token &NextToken, 598 bool IsAddressOfOperand, 599 CorrectionCandidateCallback *CCC) { 600 DeclarationNameInfo NameInfo(Name, NameLoc); 601 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 602 603 if (NextToken.is(tok::coloncolon)) { 604 BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(), 605 QualType(), false, SS, 0, false); 606 607 } 608 609 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName); 610 LookupParsedName(Result, S, &SS, !CurMethod); 611 612 // Perform lookup for Objective-C instance variables (including automatically 613 // synthesized instance variables), if we're in an Objective-C method. 614 // FIXME: This lookup really, really needs to be folded in to the normal 615 // unqualified lookup mechanism. 616 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) { 617 ExprResult E = LookupInObjCMethod(Result, S, Name, true); 618 if (E.get() || E.isInvalid()) 619 return E; 620 } 621 622 bool SecondTry = false; 623 bool IsFilteredTemplateName = false; 624 625 Corrected: 626 switch (Result.getResultKind()) { 627 case LookupResult::NotFound: 628 // If an unqualified-id is followed by a '(', then we have a function 629 // call. 630 if (!SS.isSet() && NextToken.is(tok::l_paren)) { 631 // In C++, this is an ADL-only call. 632 // FIXME: Reference? 633 if (getLangOpts().CPlusPlus) 634 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true); 635 636 // C90 6.3.2.2: 637 // If the expression that precedes the parenthesized argument list in a 638 // function call consists solely of an identifier, and if no 639 // declaration is visible for this identifier, the identifier is 640 // implicitly declared exactly as if, in the innermost block containing 641 // the function call, the declaration 642 // 643 // extern int identifier (); 644 // 645 // appeared. 646 // 647 // We also allow this in C99 as an extension. 648 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) { 649 Result.addDecl(D); 650 Result.resolveKind(); 651 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false); 652 } 653 } 654 655 // In C, we first see whether there is a tag type by the same name, in 656 // which case it's likely that the user just forget to write "enum", 657 // "struct", or "union". 658 if (!getLangOpts().CPlusPlus && !SecondTry && 659 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) { 660 break; 661 } 662 663 // Perform typo correction to determine if there is another name that is 664 // close to this name. 665 if (!SecondTry && CCC) { 666 SecondTry = true; 667 if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(), 668 Result.getLookupKind(), S, 669 &SS, *CCC)) { 670 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest; 671 unsigned QualifiedDiag = diag::err_no_member_suggest; 672 std::string CorrectedStr(Corrected.getAsString(getLangOpts())); 673 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); 674 675 NamedDecl *FirstDecl = Corrected.getCorrectionDecl(); 676 NamedDecl *UnderlyingFirstDecl 677 = FirstDecl? FirstDecl->getUnderlyingDecl() : 0; 678 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && 679 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) { 680 UnqualifiedDiag = diag::err_no_template_suggest; 681 QualifiedDiag = diag::err_no_member_template_suggest; 682 } else if (UnderlyingFirstDecl && 683 (isa<TypeDecl>(UnderlyingFirstDecl) || 684 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) || 685 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) { 686 UnqualifiedDiag = diag::err_unknown_typename_suggest; 687 QualifiedDiag = diag::err_unknown_nested_typename_suggest; 688 } 689 690 if (SS.isEmpty()) { 691 Diag(NameLoc, UnqualifiedDiag) 692 << Name << CorrectedQuotedStr 693 << FixItHint::CreateReplacement(NameLoc, CorrectedStr); 694 } else {// FIXME: is this even reachable? Test it. 695 bool droppedSpecifier = Corrected.WillReplaceSpecifier() && 696 Name->getName().equals(CorrectedStr); 697 Diag(NameLoc, QualifiedDiag) 698 << Name << computeDeclContext(SS, false) << droppedSpecifier 699 << CorrectedQuotedStr << SS.getRange() 700 << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), 701 CorrectedStr); 702 } 703 704 // Update the name, so that the caller has the new name. 705 Name = Corrected.getCorrectionAsIdentifierInfo(); 706 707 // Typo correction corrected to a keyword. 708 if (Corrected.isKeyword()) 709 return Corrected.getCorrectionAsIdentifierInfo(); 710 711 // Also update the LookupResult... 712 // FIXME: This should probably go away at some point 713 Result.clear(); 714 Result.setLookupName(Corrected.getCorrection()); 715 if (FirstDecl) { 716 Result.addDecl(FirstDecl); 717 Diag(FirstDecl->getLocation(), diag::note_previous_decl) 718 << CorrectedQuotedStr; 719 } 720 721 // If we found an Objective-C instance variable, let 722 // LookupInObjCMethod build the appropriate expression to 723 // reference the ivar. 724 // FIXME: This is a gross hack. 725 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) { 726 Result.clear(); 727 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier())); 728 return E; 729 } 730 731 goto Corrected; 732 } 733 } 734 735 // We failed to correct; just fall through and let the parser deal with it. 736 Result.suppressDiagnostics(); 737 return NameClassification::Unknown(); 738 739 case LookupResult::NotFoundInCurrentInstantiation: { 740 // We performed name lookup into the current instantiation, and there were 741 // dependent bases, so we treat this result the same way as any other 742 // dependent nested-name-specifier. 743 744 // C++ [temp.res]p2: 745 // A name used in a template declaration or definition and that is 746 // dependent on a template-parameter is assumed not to name a type 747 // unless the applicable name lookup finds a type name or the name is 748 // qualified by the keyword typename. 749 // 750 // FIXME: If the next token is '<', we might want to ask the parser to 751 // perform some heroics to see if we actually have a 752 // template-argument-list, which would indicate a missing 'template' 753 // keyword here. 754 return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(), 755 NameInfo, IsAddressOfOperand, 756 /*TemplateArgs=*/0); 757 } 758 759 case LookupResult::Found: 760 case LookupResult::FoundOverloaded: 761 case LookupResult::FoundUnresolvedValue: 762 break; 763 764 case LookupResult::Ambiguous: 765 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && 766 hasAnyAcceptableTemplateNames(Result)) { 767 // C++ [temp.local]p3: 768 // A lookup that finds an injected-class-name (10.2) can result in an 769 // ambiguity in certain cases (for example, if it is found in more than 770 // one base class). If all of the injected-class-names that are found 771 // refer to specializations of the same class template, and if the name 772 // is followed by a template-argument-list, the reference refers to the 773 // class template itself and not a specialization thereof, and is not 774 // ambiguous. 775 // 776 // This filtering can make an ambiguous result into an unambiguous one, 777 // so try again after filtering out template names. 778 FilterAcceptableTemplateNames(Result); 779 if (!Result.isAmbiguous()) { 780 IsFilteredTemplateName = true; 781 break; 782 } 783 } 784 785 // Diagnose the ambiguity and return an error. 786 return NameClassification::Error(); 787 } 788 789 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && 790 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) { 791 // C++ [temp.names]p3: 792 // After name lookup (3.4) finds that a name is a template-name or that 793 // an operator-function-id or a literal- operator-id refers to a set of 794 // overloaded functions any member of which is a function template if 795 // this is followed by a <, the < is always taken as the delimiter of a 796 // template-argument-list and never as the less-than operator. 797 if (!IsFilteredTemplateName) 798 FilterAcceptableTemplateNames(Result); 799 800 if (!Result.empty()) { 801 bool IsFunctionTemplate; 802 bool IsVarTemplate; 803 TemplateName Template; 804 if (Result.end() - Result.begin() > 1) { 805 IsFunctionTemplate = true; 806 Template = Context.getOverloadedTemplateName(Result.begin(), 807 Result.end()); 808 } else { 809 TemplateDecl *TD 810 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl()); 811 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD); 812 IsVarTemplate = isa<VarTemplateDecl>(TD); 813 814 if (SS.isSet() && !SS.isInvalid()) 815 Template = Context.getQualifiedTemplateName(SS.getScopeRep(), 816 /*TemplateKeyword=*/false, 817 TD); 818 else 819 Template = TemplateName(TD); 820 } 821 822 if (IsFunctionTemplate) { 823 // Function templates always go through overload resolution, at which 824 // point we'll perform the various checks (e.g., accessibility) we need 825 // to based on which function we selected. 826 Result.suppressDiagnostics(); 827 828 return NameClassification::FunctionTemplate(Template); 829 } 830 831 return IsVarTemplate ? NameClassification::VarTemplate(Template) 832 : NameClassification::TypeTemplate(Template); 833 } 834 } 835 836 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl(); 837 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) { 838 DiagnoseUseOfDecl(Type, NameLoc); 839 QualType T = Context.getTypeDeclType(Type); 840 if (SS.isNotEmpty()) 841 return buildNestedType(*this, SS, T, NameLoc); 842 return ParsedType::make(T); 843 } 844 845 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl); 846 if (!Class) { 847 // FIXME: It's unfortunate that we don't have a Type node for handling this. 848 if (ObjCCompatibleAliasDecl *Alias 849 = dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl)) 850 Class = Alias->getClassInterface(); 851 } 852 853 if (Class) { 854 DiagnoseUseOfDecl(Class, NameLoc); 855 856 if (NextToken.is(tok::period)) { 857 // Interface. <something> is parsed as a property reference expression. 858 // Just return "unknown" as a fall-through for now. 859 Result.suppressDiagnostics(); 860 return NameClassification::Unknown(); 861 } 862 863 QualType T = Context.getObjCInterfaceType(Class); 864 return ParsedType::make(T); 865 } 866 867 // We can have a type template here if we're classifying a template argument. 868 if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl)) 869 return NameClassification::TypeTemplate( 870 TemplateName(cast<TemplateDecl>(FirstDecl))); 871 872 // Check for a tag type hidden by a non-type decl in a few cases where it 873 // seems likely a type is wanted instead of the non-type that was found. 874 bool NextIsOp = NextToken.is(tok::amp) || NextToken.is(tok::star); 875 if ((NextToken.is(tok::identifier) || 876 (NextIsOp && FirstDecl->isFunctionOrFunctionTemplate())) && 877 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) { 878 TypeDecl *Type = Result.getAsSingle<TypeDecl>(); 879 DiagnoseUseOfDecl(Type, NameLoc); 880 QualType T = Context.getTypeDeclType(Type); 881 if (SS.isNotEmpty()) 882 return buildNestedType(*this, SS, T, NameLoc); 883 return ParsedType::make(T); 884 } 885 886 if (FirstDecl->isCXXClassMember()) 887 return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result, 0); 888 889 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren)); 890 return BuildDeclarationNameExpr(SS, Result, ADL); 891 } 892 893 // Determines the context to return to after temporarily entering a 894 // context. This depends in an unnecessarily complicated way on the 895 // exact ordering of callbacks from the parser. 896 DeclContext *Sema::getContainingDC(DeclContext *DC) { 897 898 // Functions defined inline within classes aren't parsed until we've 899 // finished parsing the top-level class, so the top-level class is 900 // the context we'll need to return to. 901 if (isa<FunctionDecl>(DC)) { 902 DC = DC->getLexicalParent(); 903 904 // A function not defined within a class will always return to its 905 // lexical context. 906 if (!isa<CXXRecordDecl>(DC)) 907 return DC; 908 909 // A C++ inline method/friend is parsed *after* the topmost class 910 // it was declared in is fully parsed ("complete"); the topmost 911 // class is the context we need to return to. 912 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 913 DC = RD; 914 915 // Return the declaration context of the topmost class the inline method is 916 // declared in. 917 return DC; 918 } 919 920 return DC->getLexicalParent(); 921 } 922 923 void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 924 assert(getContainingDC(DC) == CurContext && 925 "The next DeclContext should be lexically contained in the current one."); 926 CurContext = DC; 927 S->setEntity(DC); 928 } 929 930 void Sema::PopDeclContext() { 931 assert(CurContext && "DeclContext imbalance!"); 932 933 CurContext = getContainingDC(CurContext); 934 assert(CurContext && "Popped translation unit!"); 935 } 936 937 /// EnterDeclaratorContext - Used when we must lookup names in the context 938 /// of a declarator's nested name specifier. 939 /// 940 void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 941 // C++0x [basic.lookup.unqual]p13: 942 // A name used in the definition of a static data member of class 943 // X (after the qualified-id of the static member) is looked up as 944 // if the name was used in a member function of X. 945 // C++0x [basic.lookup.unqual]p14: 946 // If a variable member of a namespace is defined outside of the 947 // scope of its namespace then any name used in the definition of 948 // the variable member (after the declarator-id) is looked up as 949 // if the definition of the variable member occurred in its 950 // namespace. 951 // Both of these imply that we should push a scope whose context 952 // is the semantic context of the declaration. We can't use 953 // PushDeclContext here because that context is not necessarily 954 // lexically contained in the current context. Fortunately, 955 // the containing scope should have the appropriate information. 956 957 assert(!S->getEntity() && "scope already has entity"); 958 959 #ifndef NDEBUG 960 Scope *Ancestor = S->getParent(); 961 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 962 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 963 #endif 964 965 CurContext = DC; 966 S->setEntity(DC); 967 } 968 969 void Sema::ExitDeclaratorContext(Scope *S) { 970 assert(S->getEntity() == CurContext && "Context imbalance!"); 971 972 // Switch back to the lexical context. The safety of this is 973 // enforced by an assert in EnterDeclaratorContext. 974 Scope *Ancestor = S->getParent(); 975 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 976 CurContext = (DeclContext*) Ancestor->getEntity(); 977 978 // We don't need to do anything with the scope, which is going to 979 // disappear. 980 } 981 982 983 void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) { 984 FunctionDecl *FD = dyn_cast<FunctionDecl>(D); 985 if (FunctionTemplateDecl *TFD = dyn_cast_or_null<FunctionTemplateDecl>(D)) { 986 // We assume that the caller has already called 987 // ActOnReenterTemplateScope 988 FD = TFD->getTemplatedDecl(); 989 } 990 if (!FD) 991 return; 992 993 // Same implementation as PushDeclContext, but enters the context 994 // from the lexical parent, rather than the top-level class. 995 assert(CurContext == FD->getLexicalParent() && 996 "The next DeclContext should be lexically contained in the current one."); 997 CurContext = FD; 998 S->setEntity(CurContext); 999 1000 for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) { 1001 ParmVarDecl *Param = FD->getParamDecl(P); 1002 // If the parameter has an identifier, then add it to the scope 1003 if (Param->getIdentifier()) { 1004 S->AddDecl(Param); 1005 IdResolver.AddDecl(Param); 1006 } 1007 } 1008 } 1009 1010 1011 void Sema::ActOnExitFunctionContext() { 1012 // Same implementation as PopDeclContext, but returns to the lexical parent, 1013 // rather than the top-level class. 1014 assert(CurContext && "DeclContext imbalance!"); 1015 CurContext = CurContext->getLexicalParent(); 1016 assert(CurContext && "Popped translation unit!"); 1017 } 1018 1019 1020 /// \brief Determine whether we allow overloading of the function 1021 /// PrevDecl with another declaration. 1022 /// 1023 /// This routine determines whether overloading is possible, not 1024 /// whether some new function is actually an overload. It will return 1025 /// true in C++ (where we can always provide overloads) or, as an 1026 /// extension, in C when the previous function is already an 1027 /// overloaded function declaration or has the "overloadable" 1028 /// attribute. 1029 static bool AllowOverloadingOfFunction(LookupResult &Previous, 1030 ASTContext &Context) { 1031 if (Context.getLangOpts().CPlusPlus) 1032 return true; 1033 1034 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 1035 return true; 1036 1037 return (Previous.getResultKind() == LookupResult::Found 1038 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 1039 } 1040 1041 /// Add this decl to the scope shadowed decl chains. 1042 void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 1043 // Move up the scope chain until we find the nearest enclosing 1044 // non-transparent context. The declaration will be introduced into this 1045 // scope. 1046 while (S->getEntity() && 1047 ((DeclContext *)S->getEntity())->isTransparentContext()) 1048 S = S->getParent(); 1049 1050 // Add scoped declarations into their context, so that they can be 1051 // found later. Declarations without a context won't be inserted 1052 // into any context. 1053 if (AddToContext) 1054 CurContext->addDecl(D); 1055 1056 // Out-of-line definitions shouldn't be pushed into scope in C++. 1057 // Out-of-line variable and function definitions shouldn't even in C. 1058 if ((getLangOpts().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 1059 D->isOutOfLine() && 1060 !D->getDeclContext()->getRedeclContext()->Equals( 1061 D->getLexicalDeclContext()->getRedeclContext())) 1062 return; 1063 1064 // Template instantiations should also not be pushed into scope. 1065 if (isa<FunctionDecl>(D) && 1066 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 1067 return; 1068 1069 // If this replaces anything in the current scope, 1070 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 1071 IEnd = IdResolver.end(); 1072 for (; I != IEnd; ++I) { 1073 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 1074 S->RemoveDecl(*I); 1075 IdResolver.RemoveDecl(*I); 1076 1077 // Should only need to replace one decl. 1078 break; 1079 } 1080 } 1081 1082 S->AddDecl(D); 1083 1084 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { 1085 // Implicitly-generated labels may end up getting generated in an order that 1086 // isn't strictly lexical, which breaks name lookup. Be careful to insert 1087 // the label at the appropriate place in the identifier chain. 1088 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { 1089 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext(); 1090 if (IDC == CurContext) { 1091 if (!S->isDeclScope(*I)) 1092 continue; 1093 } else if (IDC->Encloses(CurContext)) 1094 break; 1095 } 1096 1097 IdResolver.InsertDeclAfter(I, D); 1098 } else { 1099 IdResolver.AddDecl(D); 1100 } 1101 } 1102 1103 void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) { 1104 if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope) 1105 TUScope->AddDecl(D); 1106 } 1107 1108 bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S, 1109 bool ExplicitInstantiationOrSpecialization) { 1110 return IdResolver.isDeclInScope(D, Ctx, S, 1111 ExplicitInstantiationOrSpecialization); 1112 } 1113 1114 Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 1115 DeclContext *TargetDC = DC->getPrimaryContext(); 1116 do { 1117 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 1118 if (ScopeDC->getPrimaryContext() == TargetDC) 1119 return S; 1120 } while ((S = S->getParent())); 1121 1122 return 0; 1123 } 1124 1125 static bool isOutOfScopePreviousDeclaration(NamedDecl *, 1126 DeclContext*, 1127 ASTContext&); 1128 1129 /// Filters out lookup results that don't fall within the given scope 1130 /// as determined by isDeclInScope. 1131 void Sema::FilterLookupForScope(LookupResult &R, 1132 DeclContext *Ctx, Scope *S, 1133 bool ConsiderLinkage, 1134 bool ExplicitInstantiationOrSpecialization) { 1135 LookupResult::Filter F = R.makeFilter(); 1136 while (F.hasNext()) { 1137 NamedDecl *D = F.next(); 1138 1139 if (isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization)) 1140 continue; 1141 1142 if (ConsiderLinkage && 1143 isOutOfScopePreviousDeclaration(D, Ctx, Context)) 1144 continue; 1145 1146 F.erase(); 1147 } 1148 1149 F.done(); 1150 } 1151 1152 static bool isUsingDecl(NamedDecl *D) { 1153 return isa<UsingShadowDecl>(D) || 1154 isa<UnresolvedUsingTypenameDecl>(D) || 1155 isa<UnresolvedUsingValueDecl>(D); 1156 } 1157 1158 /// Removes using shadow declarations from the lookup results. 1159 static void RemoveUsingDecls(LookupResult &R) { 1160 LookupResult::Filter F = R.makeFilter(); 1161 while (F.hasNext()) 1162 if (isUsingDecl(F.next())) 1163 F.erase(); 1164 1165 F.done(); 1166 } 1167 1168 /// \brief Check for this common pattern: 1169 /// @code 1170 /// class S { 1171 /// S(const S&); // DO NOT IMPLEMENT 1172 /// void operator=(const S&); // DO NOT IMPLEMENT 1173 /// }; 1174 /// @endcode 1175 static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 1176 // FIXME: Should check for private access too but access is set after we get 1177 // the decl here. 1178 if (D->doesThisDeclarationHaveABody()) 1179 return false; 1180 1181 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 1182 return CD->isCopyConstructor(); 1183 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 1184 return Method->isCopyAssignmentOperator(); 1185 return false; 1186 } 1187 1188 // We need this to handle 1189 // 1190 // typedef struct { 1191 // void *foo() { return 0; } 1192 // } A; 1193 // 1194 // When we see foo we don't know if after the typedef we will get 'A' or '*A' 1195 // for example. If 'A', foo will have external linkage. If we have '*A', 1196 // foo will have no linkage. Since we can't know untill we get to the end 1197 // of the typedef, this function finds out if D might have non external linkage. 1198 // Callers should verify at the end of the TU if it D has external linkage or 1199 // not. 1200 bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) { 1201 const DeclContext *DC = D->getDeclContext(); 1202 while (!DC->isTranslationUnit()) { 1203 if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){ 1204 if (!RD->hasNameForLinkage()) 1205 return true; 1206 } 1207 DC = DC->getParent(); 1208 } 1209 1210 return !D->isExternallyVisible(); 1211 } 1212 1213 bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 1214 assert(D); 1215 1216 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 1217 return false; 1218 1219 // Ignore class templates. 1220 if (D->getDeclContext()->isDependentContext() || 1221 D->getLexicalDeclContext()->isDependentContext()) 1222 return false; 1223 1224 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1225 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 1226 return false; 1227 1228 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 1229 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 1230 return false; 1231 } else { 1232 // 'static inline' functions are used in headers; don't warn. 1233 // Make sure we get the storage class from the canonical declaration, 1234 // since otherwise we will get spurious warnings on specialized 1235 // static template functions. 1236 if (FD->getCanonicalDecl()->getStorageClass() == SC_Static && 1237 FD->isInlineSpecified()) 1238 return false; 1239 } 1240 1241 if (FD->doesThisDeclarationHaveABody() && 1242 Context.DeclMustBeEmitted(FD)) 1243 return false; 1244 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1245 // Don't warn on variables of const-qualified or reference type, since their 1246 // values can be used even if though they're not odr-used, and because const 1247 // qualified variables can appear in headers in contexts where they're not 1248 // intended to be used. 1249 // FIXME: Use more principled rules for these exemptions. 1250 if (!VD->isFileVarDecl() || 1251 VD->getType().isConstQualified() || 1252 VD->getType()->isReferenceType() || 1253 Context.DeclMustBeEmitted(VD)) 1254 return false; 1255 1256 if (VD->isStaticDataMember() && 1257 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 1258 return false; 1259 1260 } else { 1261 return false; 1262 } 1263 1264 // Only warn for unused decls internal to the translation unit. 1265 return mightHaveNonExternalLinkage(D); 1266 } 1267 1268 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 1269 if (!D) 1270 return; 1271 1272 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1273 const FunctionDecl *First = FD->getFirstDeclaration(); 1274 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 1275 return; // First should already be in the vector. 1276 } 1277 1278 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1279 const VarDecl *First = VD->getFirstDeclaration(); 1280 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 1281 return; // First should already be in the vector. 1282 } 1283 1284 if (ShouldWarnIfUnusedFileScopedDecl(D)) 1285 UnusedFileScopedDecls.push_back(D); 1286 } 1287 1288 static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 1289 if (D->isInvalidDecl()) 1290 return false; 1291 1292 if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>()) 1293 return false; 1294 1295 if (isa<LabelDecl>(D)) 1296 return true; 1297 1298 // White-list anything that isn't a local variable. 1299 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 1300 !D->getDeclContext()->isFunctionOrMethod()) 1301 return false; 1302 1303 // Types of valid local variables should be complete, so this should succeed. 1304 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1305 1306 // White-list anything with an __attribute__((unused)) type. 1307 QualType Ty = VD->getType(); 1308 1309 // Only look at the outermost level of typedef. 1310 if (const TypedefType *TT = Ty->getAs<TypedefType>()) { 1311 if (TT->getDecl()->hasAttr<UnusedAttr>()) 1312 return false; 1313 } 1314 1315 // If we failed to complete the type for some reason, or if the type is 1316 // dependent, don't diagnose the variable. 1317 if (Ty->isIncompleteType() || Ty->isDependentType()) 1318 return false; 1319 1320 if (const TagType *TT = Ty->getAs<TagType>()) { 1321 const TagDecl *Tag = TT->getDecl(); 1322 if (Tag->hasAttr<UnusedAttr>()) 1323 return false; 1324 1325 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 1326 if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>()) 1327 return false; 1328 1329 if (const Expr *Init = VD->getInit()) { 1330 if (const ExprWithCleanups *Cleanups = dyn_cast<ExprWithCleanups>(Init)) 1331 Init = Cleanups->getSubExpr(); 1332 const CXXConstructExpr *Construct = 1333 dyn_cast<CXXConstructExpr>(Init); 1334 if (Construct && !Construct->isElidable()) { 1335 CXXConstructorDecl *CD = Construct->getConstructor(); 1336 if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>()) 1337 return false; 1338 } 1339 } 1340 } 1341 } 1342 1343 // TODO: __attribute__((unused)) templates? 1344 } 1345 1346 return true; 1347 } 1348 1349 static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx, 1350 FixItHint &Hint) { 1351 if (isa<LabelDecl>(D)) { 1352 SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(), 1353 tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true); 1354 if (AfterColon.isInvalid()) 1355 return; 1356 Hint = FixItHint::CreateRemoval(CharSourceRange:: 1357 getCharRange(D->getLocStart(), AfterColon)); 1358 } 1359 return; 1360 } 1361 1362 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used 1363 /// unless they are marked attr(unused). 1364 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 1365 FixItHint Hint; 1366 if (!ShouldDiagnoseUnusedDecl(D)) 1367 return; 1368 1369 GenerateFixForUnusedDecl(D, Context, Hint); 1370 1371 unsigned DiagID; 1372 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 1373 DiagID = diag::warn_unused_exception_param; 1374 else if (isa<LabelDecl>(D)) 1375 DiagID = diag::warn_unused_label; 1376 else 1377 DiagID = diag::warn_unused_variable; 1378 1379 Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint; 1380 } 1381 1382 static void CheckPoppedLabel(LabelDecl *L, Sema &S) { 1383 // Verify that we have no forward references left. If so, there was a goto 1384 // or address of a label taken, but no definition of it. Label fwd 1385 // definitions are indicated with a null substmt. 1386 if (L->getStmt() == 0) 1387 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); 1388 } 1389 1390 void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 1391 if (S->decl_empty()) return; 1392 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 1393 "Scope shouldn't contain decls!"); 1394 1395 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 1396 I != E; ++I) { 1397 Decl *TmpD = (*I); 1398 assert(TmpD && "This decl didn't get pushed??"); 1399 1400 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 1401 NamedDecl *D = cast<NamedDecl>(TmpD); 1402 1403 if (!D->getDeclName()) continue; 1404 1405 // Diagnose unused variables in this scope. 1406 if (!S->hasUnrecoverableErrorOccurred()) 1407 DiagnoseUnusedDecl(D); 1408 1409 // If this was a forward reference to a label, verify it was defined. 1410 if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) 1411 CheckPoppedLabel(LD, *this); 1412 1413 // Remove this name from our lexical scope. 1414 IdResolver.RemoveDecl(D); 1415 } 1416 } 1417 1418 void Sema::ActOnStartFunctionDeclarator() { 1419 ++InFunctionDeclarator; 1420 } 1421 1422 void Sema::ActOnEndFunctionDeclarator() { 1423 assert(InFunctionDeclarator); 1424 --InFunctionDeclarator; 1425 } 1426 1427 /// \brief Look for an Objective-C class in the translation unit. 1428 /// 1429 /// \param Id The name of the Objective-C class we're looking for. If 1430 /// typo-correction fixes this name, the Id will be updated 1431 /// to the fixed name. 1432 /// 1433 /// \param IdLoc The location of the name in the translation unit. 1434 /// 1435 /// \param DoTypoCorrection If true, this routine will attempt typo correction 1436 /// if there is no class with the given name. 1437 /// 1438 /// \returns The declaration of the named Objective-C class, or NULL if the 1439 /// class could not be found. 1440 ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 1441 SourceLocation IdLoc, 1442 bool DoTypoCorrection) { 1443 // The third "scope" argument is 0 since we aren't enabling lazy built-in 1444 // creation from this context. 1445 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 1446 1447 if (!IDecl && DoTypoCorrection) { 1448 // Perform typo correction at the given location, but only if we 1449 // find an Objective-C class name. 1450 DeclFilterCCC<ObjCInterfaceDecl> Validator; 1451 if (TypoCorrection C = CorrectTypo(DeclarationNameInfo(Id, IdLoc), 1452 LookupOrdinaryName, TUScope, NULL, 1453 Validator)) { 1454 IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>(); 1455 Diag(IdLoc, diag::err_undef_interface_suggest) 1456 << Id << IDecl->getDeclName() 1457 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 1458 Diag(IDecl->getLocation(), diag::note_previous_decl) 1459 << IDecl->getDeclName(); 1460 1461 Id = IDecl->getIdentifier(); 1462 } 1463 } 1464 ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 1465 // This routine must always return a class definition, if any. 1466 if (Def && Def->getDefinition()) 1467 Def = Def->getDefinition(); 1468 return Def; 1469 } 1470 1471 /// getNonFieldDeclScope - Retrieves the innermost scope, starting 1472 /// from S, where a non-field would be declared. This routine copes 1473 /// with the difference between C and C++ scoping rules in structs and 1474 /// unions. For example, the following code is well-formed in C but 1475 /// ill-formed in C++: 1476 /// @code 1477 /// struct S6 { 1478 /// enum { BAR } e; 1479 /// }; 1480 /// 1481 /// void test_S6() { 1482 /// struct S6 a; 1483 /// a.e = BAR; 1484 /// } 1485 /// @endcode 1486 /// For the declaration of BAR, this routine will return a different 1487 /// scope. The scope S will be the scope of the unnamed enumeration 1488 /// within S6. In C++, this routine will return the scope associated 1489 /// with S6, because the enumeration's scope is a transparent 1490 /// context but structures can contain non-field names. In C, this 1491 /// routine will return the translation unit scope, since the 1492 /// enumeration's scope is a transparent context and structures cannot 1493 /// contain non-field names. 1494 Scope *Sema::getNonFieldDeclScope(Scope *S) { 1495 while (((S->getFlags() & Scope::DeclScope) == 0) || 1496 (S->getEntity() && 1497 ((DeclContext *)S->getEntity())->isTransparentContext()) || 1498 (S->isClassScope() && !getLangOpts().CPlusPlus)) 1499 S = S->getParent(); 1500 return S; 1501 } 1502 1503 /// \brief Looks up the declaration of "struct objc_super" and 1504 /// saves it for later use in building builtin declaration of 1505 /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such 1506 /// pre-existing declaration exists no action takes place. 1507 static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S, 1508 IdentifierInfo *II) { 1509 if (!II->isStr("objc_msgSendSuper")) 1510 return; 1511 ASTContext &Context = ThisSema.Context; 1512 1513 LookupResult Result(ThisSema, &Context.Idents.get("objc_super"), 1514 SourceLocation(), Sema::LookupTagName); 1515 ThisSema.LookupName(Result, S); 1516 if (Result.getResultKind() == LookupResult::Found) 1517 if (const TagDecl *TD = Result.getAsSingle<TagDecl>()) 1518 Context.setObjCSuperType(Context.getTagDeclType(TD)); 1519 } 1520 1521 /// LazilyCreateBuiltin - The specified Builtin-ID was first used at 1522 /// file scope. lazily create a decl for it. ForRedeclaration is true 1523 /// if we're creating this built-in in anticipation of redeclaring the 1524 /// built-in. 1525 NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 1526 Scope *S, bool ForRedeclaration, 1527 SourceLocation Loc) { 1528 LookupPredefedObjCSuperType(*this, S, II); 1529 1530 Builtin::ID BID = (Builtin::ID)bid; 1531 1532 ASTContext::GetBuiltinTypeError Error; 1533 QualType R = Context.GetBuiltinType(BID, Error); 1534 switch (Error) { 1535 case ASTContext::GE_None: 1536 // Okay 1537 break; 1538 1539 case ASTContext::GE_Missing_stdio: 1540 if (ForRedeclaration) 1541 Diag(Loc, diag::warn_implicit_decl_requires_stdio) 1542 << Context.BuiltinInfo.GetName(BID); 1543 return 0; 1544 1545 case ASTContext::GE_Missing_setjmp: 1546 if (ForRedeclaration) 1547 Diag(Loc, diag::warn_implicit_decl_requires_setjmp) 1548 << Context.BuiltinInfo.GetName(BID); 1549 return 0; 1550 1551 case ASTContext::GE_Missing_ucontext: 1552 if (ForRedeclaration) 1553 Diag(Loc, diag::warn_implicit_decl_requires_ucontext) 1554 << Context.BuiltinInfo.GetName(BID); 1555 return 0; 1556 } 1557 1558 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 1559 Diag(Loc, diag::ext_implicit_lib_function_decl) 1560 << Context.BuiltinInfo.GetName(BID) 1561 << R; 1562 if (Context.BuiltinInfo.getHeaderName(BID) && 1563 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) 1564 != DiagnosticsEngine::Ignored) 1565 Diag(Loc, diag::note_please_include_header) 1566 << Context.BuiltinInfo.getHeaderName(BID) 1567 << Context.BuiltinInfo.GetName(BID); 1568 } 1569 1570 FunctionDecl *New = FunctionDecl::Create(Context, 1571 Context.getTranslationUnitDecl(), 1572 Loc, Loc, II, R, /*TInfo=*/0, 1573 SC_Extern, 1574 false, 1575 /*hasPrototype=*/true); 1576 New->setImplicit(); 1577 1578 // Create Decl objects for each parameter, adding them to the 1579 // FunctionDecl. 1580 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 1581 SmallVector<ParmVarDecl*, 16> Params; 1582 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) { 1583 ParmVarDecl *parm = 1584 ParmVarDecl::Create(Context, New, SourceLocation(), 1585 SourceLocation(), 0, 1586 FT->getArgType(i), /*TInfo=*/0, 1587 SC_None, 0); 1588 parm->setScopeInfo(0, i); 1589 Params.push_back(parm); 1590 } 1591 New->setParams(Params); 1592 } 1593 1594 AddKnownFunctionAttributes(New); 1595 1596 // TUScope is the translation-unit scope to insert this function into. 1597 // FIXME: This is hideous. We need to teach PushOnScopeChains to 1598 // relate Scopes to DeclContexts, and probably eliminate CurContext 1599 // entirely, but we're not there yet. 1600 DeclContext *SavedContext = CurContext; 1601 CurContext = Context.getTranslationUnitDecl(); 1602 PushOnScopeChains(New, TUScope); 1603 CurContext = SavedContext; 1604 return New; 1605 } 1606 1607 /// \brief Filter out any previous declarations that the given declaration 1608 /// should not consider because they are not permitted to conflict, e.g., 1609 /// because they come from hidden sub-modules and do not refer to the same 1610 /// entity. 1611 static void filterNonConflictingPreviousDecls(ASTContext &context, 1612 NamedDecl *decl, 1613 LookupResult &previous){ 1614 // This is only interesting when modules are enabled. 1615 if (!context.getLangOpts().Modules) 1616 return; 1617 1618 // Empty sets are uninteresting. 1619 if (previous.empty()) 1620 return; 1621 1622 LookupResult::Filter filter = previous.makeFilter(); 1623 while (filter.hasNext()) { 1624 NamedDecl *old = filter.next(); 1625 1626 // Non-hidden declarations are never ignored. 1627 if (!old->isHidden()) 1628 continue; 1629 1630 if (!old->isExternallyVisible()) 1631 filter.erase(); 1632 } 1633 1634 filter.done(); 1635 } 1636 1637 bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) { 1638 QualType OldType; 1639 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old)) 1640 OldType = OldTypedef->getUnderlyingType(); 1641 else 1642 OldType = Context.getTypeDeclType(Old); 1643 QualType NewType = New->getUnderlyingType(); 1644 1645 if (NewType->isVariablyModifiedType()) { 1646 // Must not redefine a typedef with a variably-modified type. 1647 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0; 1648 Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef) 1649 << Kind << NewType; 1650 if (Old->getLocation().isValid()) 1651 Diag(Old->getLocation(), diag::note_previous_definition); 1652 New->setInvalidDecl(); 1653 return true; 1654 } 1655 1656 if (OldType != NewType && 1657 !OldType->isDependentType() && 1658 !NewType->isDependentType() && 1659 !Context.hasSameType(OldType, NewType)) { 1660 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0; 1661 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 1662 << Kind << NewType << OldType; 1663 if (Old->getLocation().isValid()) 1664 Diag(Old->getLocation(), diag::note_previous_definition); 1665 New->setInvalidDecl(); 1666 return true; 1667 } 1668 return false; 1669 } 1670 1671 /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the 1672 /// same name and scope as a previous declaration 'Old'. Figure out 1673 /// how to resolve this situation, merging decls or emitting 1674 /// diagnostics as appropriate. If there was an error, set New to be invalid. 1675 /// 1676 void Sema::MergeTypedefNameDecl(TypedefNameDecl *New, LookupResult &OldDecls) { 1677 // If the new decl is known invalid already, don't bother doing any 1678 // merging checks. 1679 if (New->isInvalidDecl()) return; 1680 1681 // Allow multiple definitions for ObjC built-in typedefs. 1682 // FIXME: Verify the underlying types are equivalent! 1683 if (getLangOpts().ObjC1) { 1684 const IdentifierInfo *TypeID = New->getIdentifier(); 1685 switch (TypeID->getLength()) { 1686 default: break; 1687 case 2: 1688 { 1689 if (!TypeID->isStr("id")) 1690 break; 1691 QualType T = New->getUnderlyingType(); 1692 if (!T->isPointerType()) 1693 break; 1694 if (!T->isVoidPointerType()) { 1695 QualType PT = T->getAs<PointerType>()->getPointeeType(); 1696 if (!PT->isStructureType()) 1697 break; 1698 } 1699 Context.setObjCIdRedefinitionType(T); 1700 // Install the built-in type for 'id', ignoring the current definition. 1701 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 1702 return; 1703 } 1704 case 5: 1705 if (!TypeID->isStr("Class")) 1706 break; 1707 Context.setObjCClassRedefinitionType(New->getUnderlyingType()); 1708 // Install the built-in type for 'Class', ignoring the current definition. 1709 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 1710 return; 1711 case 3: 1712 if (!TypeID->isStr("SEL")) 1713 break; 1714 Context.setObjCSelRedefinitionType(New->getUnderlyingType()); 1715 // Install the built-in type for 'SEL', ignoring the current definition. 1716 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 1717 return; 1718 } 1719 // Fall through - the typedef name was not a builtin type. 1720 } 1721 1722 // Verify the old decl was also a type. 1723 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 1724 if (!Old) { 1725 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1726 << New->getDeclName(); 1727 1728 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 1729 if (OldD->getLocation().isValid()) 1730 Diag(OldD->getLocation(), diag::note_previous_definition); 1731 1732 return New->setInvalidDecl(); 1733 } 1734 1735 // If the old declaration is invalid, just give up here. 1736 if (Old->isInvalidDecl()) 1737 return New->setInvalidDecl(); 1738 1739 // If the typedef types are not identical, reject them in all languages and 1740 // with any extensions enabled. 1741 if (isIncompatibleTypedef(Old, New)) 1742 return; 1743 1744 // The types match. Link up the redeclaration chain if the old 1745 // declaration was a typedef. 1746 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) 1747 New->setPreviousDeclaration(Typedef); 1748 1749 mergeDeclAttributes(New, Old); 1750 1751 if (getLangOpts().MicrosoftExt) 1752 return; 1753 1754 if (getLangOpts().CPlusPlus) { 1755 // C++ [dcl.typedef]p2: 1756 // In a given non-class scope, a typedef specifier can be used to 1757 // redefine the name of any type declared in that scope to refer 1758 // to the type to which it already refers. 1759 if (!isa<CXXRecordDecl>(CurContext)) 1760 return; 1761 1762 // C++0x [dcl.typedef]p4: 1763 // In a given class scope, a typedef specifier can be used to redefine 1764 // any class-name declared in that scope that is not also a typedef-name 1765 // to refer to the type to which it already refers. 1766 // 1767 // This wording came in via DR424, which was a correction to the 1768 // wording in DR56, which accidentally banned code like: 1769 // 1770 // struct S { 1771 // typedef struct A { } A; 1772 // }; 1773 // 1774 // in the C++03 standard. We implement the C++0x semantics, which 1775 // allow the above but disallow 1776 // 1777 // struct S { 1778 // typedef int I; 1779 // typedef int I; 1780 // }; 1781 // 1782 // since that was the intent of DR56. 1783 if (!isa<TypedefNameDecl>(Old)) 1784 return; 1785 1786 Diag(New->getLocation(), diag::err_redefinition) 1787 << New->getDeclName(); 1788 Diag(Old->getLocation(), diag::note_previous_definition); 1789 return New->setInvalidDecl(); 1790 } 1791 1792 // Modules always permit redefinition of typedefs, as does C11. 1793 if (getLangOpts().Modules || getLangOpts().C11) 1794 return; 1795 1796 // If we have a redefinition of a typedef in C, emit a warning. This warning 1797 // is normally mapped to an error, but can be controlled with 1798 // -Wtypedef-redefinition. If either the original or the redefinition is 1799 // in a system header, don't emit this for compatibility with GCC. 1800 if (getDiagnostics().getSuppressSystemWarnings() && 1801 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 1802 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 1803 return; 1804 1805 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1806 << New->getDeclName(); 1807 Diag(Old->getLocation(), diag::note_previous_definition); 1808 return; 1809 } 1810 1811 /// DeclhasAttr - returns true if decl Declaration already has the target 1812 /// attribute. 1813 static bool 1814 DeclHasAttr(const Decl *D, const Attr *A) { 1815 // There can be multiple AvailabilityAttr in a Decl. Make sure we copy 1816 // all of them. It is mergeAvailabilityAttr in SemaDeclAttr.cpp that is 1817 // responsible for making sure they are consistent. 1818 const AvailabilityAttr *AA = dyn_cast<AvailabilityAttr>(A); 1819 if (AA) 1820 return false; 1821 1822 // The following thread safety attributes can also be duplicated. 1823 switch (A->getKind()) { 1824 case attr::ExclusiveLocksRequired: 1825 case attr::SharedLocksRequired: 1826 case attr::LocksExcluded: 1827 case attr::ExclusiveLockFunction: 1828 case attr::SharedLockFunction: 1829 case attr::UnlockFunction: 1830 case attr::ExclusiveTrylockFunction: 1831 case attr::SharedTrylockFunction: 1832 case attr::GuardedBy: 1833 case attr::PtGuardedBy: 1834 case attr::AcquiredBefore: 1835 case attr::AcquiredAfter: 1836 return false; 1837 default: 1838 ; 1839 } 1840 1841 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1842 const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A); 1843 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1844 if ((*i)->getKind() == A->getKind()) { 1845 if (Ann) { 1846 if (Ann->getAnnotation() == cast<AnnotateAttr>(*i)->getAnnotation()) 1847 return true; 1848 continue; 1849 } 1850 // FIXME: Don't hardcode this check 1851 if (OA && isa<OwnershipAttr>(*i)) 1852 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1853 return true; 1854 } 1855 1856 return false; 1857 } 1858 1859 static bool isAttributeTargetADefinition(Decl *D) { 1860 if (VarDecl *VD = dyn_cast<VarDecl>(D)) 1861 return VD->isThisDeclarationADefinition(); 1862 if (TagDecl *TD = dyn_cast<TagDecl>(D)) 1863 return TD->isCompleteDefinition() || TD->isBeingDefined(); 1864 return true; 1865 } 1866 1867 /// Merge alignment attributes from \p Old to \p New, taking into account the 1868 /// special semantics of C11's _Alignas specifier and C++11's alignas attribute. 1869 /// 1870 /// \return \c true if any attributes were added to \p New. 1871 static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) { 1872 // Look for alignas attributes on Old, and pick out whichever attribute 1873 // specifies the strictest alignment requirement. 1874 AlignedAttr *OldAlignasAttr = 0; 1875 AlignedAttr *OldStrictestAlignAttr = 0; 1876 unsigned OldAlign = 0; 1877 for (specific_attr_iterator<AlignedAttr> 1878 I = Old->specific_attr_begin<AlignedAttr>(), 1879 E = Old->specific_attr_end<AlignedAttr>(); I != E; ++I) { 1880 // FIXME: We have no way of representing inherited dependent alignments 1881 // in a case like: 1882 // template<int A, int B> struct alignas(A) X; 1883 // template<int A, int B> struct alignas(B) X {}; 1884 // For now, we just ignore any alignas attributes which are not on the 1885 // definition in such a case. 1886 if (I->isAlignmentDependent()) 1887 return false; 1888 1889 if (I->isAlignas()) 1890 OldAlignasAttr = *I; 1891 1892 unsigned Align = I->getAlignment(S.Context); 1893 if (Align > OldAlign) { 1894 OldAlign = Align; 1895 OldStrictestAlignAttr = *I; 1896 } 1897 } 1898 1899 // Look for alignas attributes on New. 1900 AlignedAttr *NewAlignasAttr = 0; 1901 unsigned NewAlign = 0; 1902 for (specific_attr_iterator<AlignedAttr> 1903 I = New->specific_attr_begin<AlignedAttr>(), 1904 E = New->specific_attr_end<AlignedAttr>(); I != E; ++I) { 1905 if (I->isAlignmentDependent()) 1906 return false; 1907 1908 if (I->isAlignas()) 1909 NewAlignasAttr = *I; 1910 1911 unsigned Align = I->getAlignment(S.Context); 1912 if (Align > NewAlign) 1913 NewAlign = Align; 1914 } 1915 1916 if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) { 1917 // Both declarations have 'alignas' attributes. We require them to match. 1918 // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but 1919 // fall short. (If two declarations both have alignas, they must both match 1920 // every definition, and so must match each other if there is a definition.) 1921 1922 // If either declaration only contains 'alignas(0)' specifiers, then it 1923 // specifies the natural alignment for the type. 1924 if (OldAlign == 0 || NewAlign == 0) { 1925 QualType Ty; 1926 if (ValueDecl *VD = dyn_cast<ValueDecl>(New)) 1927 Ty = VD->getType(); 1928 else 1929 Ty = S.Context.getTagDeclType(cast<TagDecl>(New)); 1930 1931 if (OldAlign == 0) 1932 OldAlign = S.Context.getTypeAlign(Ty); 1933 if (NewAlign == 0) 1934 NewAlign = S.Context.getTypeAlign(Ty); 1935 } 1936 1937 if (OldAlign != NewAlign) { 1938 S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch) 1939 << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity() 1940 << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity(); 1941 S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration); 1942 } 1943 } 1944 1945 if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) { 1946 // C++11 [dcl.align]p6: 1947 // if any declaration of an entity has an alignment-specifier, 1948 // every defining declaration of that entity shall specify an 1949 // equivalent alignment. 1950 // C11 6.7.5/7: 1951 // If the definition of an object does not have an alignment 1952 // specifier, any other declaration of that object shall also 1953 // have no alignment specifier. 1954 S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition) 1955 << OldAlignasAttr->isC11(); 1956 S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration) 1957 << OldAlignasAttr->isC11(); 1958 } 1959 1960 bool AnyAdded = false; 1961 1962 // Ensure we have an attribute representing the strictest alignment. 1963 if (OldAlign > NewAlign) { 1964 AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context); 1965 Clone->setInherited(true); 1966 New->addAttr(Clone); 1967 AnyAdded = true; 1968 } 1969 1970 // Ensure we have an alignas attribute if the old declaration had one. 1971 if (OldAlignasAttr && !NewAlignasAttr && 1972 !(AnyAdded && OldStrictestAlignAttr->isAlignas())) { 1973 AlignedAttr *Clone = OldAlignasAttr->clone(S.Context); 1974 Clone->setInherited(true); 1975 New->addAttr(Clone); 1976 AnyAdded = true; 1977 } 1978 1979 return AnyAdded; 1980 } 1981 1982 static bool mergeDeclAttribute(Sema &S, NamedDecl *D, InheritableAttr *Attr, 1983 bool Override) { 1984 InheritableAttr *NewAttr = NULL; 1985 unsigned AttrSpellingListIndex = Attr->getSpellingListIndex(); 1986 if (AvailabilityAttr *AA = dyn_cast<AvailabilityAttr>(Attr)) 1987 NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(), 1988 AA->getIntroduced(), AA->getDeprecated(), 1989 AA->getObsoleted(), AA->getUnavailable(), 1990 AA->getMessage(), Override, 1991 AttrSpellingListIndex); 1992 else if (VisibilityAttr *VA = dyn_cast<VisibilityAttr>(Attr)) 1993 NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(), 1994 AttrSpellingListIndex); 1995 else if (TypeVisibilityAttr *VA = dyn_cast<TypeVisibilityAttr>(Attr)) 1996 NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(), 1997 AttrSpellingListIndex); 1998 else if (DLLImportAttr *ImportA = dyn_cast<DLLImportAttr>(Attr)) 1999 NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(), 2000 AttrSpellingListIndex); 2001 else if (DLLExportAttr *ExportA = dyn_cast<DLLExportAttr>(Attr)) 2002 NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(), 2003 AttrSpellingListIndex); 2004 else if (FormatAttr *FA = dyn_cast<FormatAttr>(Attr)) 2005 NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(), 2006 FA->getFormatIdx(), FA->getFirstArg(), 2007 AttrSpellingListIndex); 2008 else if (SectionAttr *SA = dyn_cast<SectionAttr>(Attr)) 2009 NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(), 2010 AttrSpellingListIndex); 2011 else if (isa<AlignedAttr>(Attr)) 2012 // AlignedAttrs are handled separately, because we need to handle all 2013 // such attributes on a declaration at the same time. 2014 NewAttr = 0; 2015 else if (!DeclHasAttr(D, Attr)) 2016 NewAttr = cast<InheritableAttr>(Attr->clone(S.Context)); 2017 2018 if (NewAttr) { 2019 NewAttr->setInherited(true); 2020 D->addAttr(NewAttr); 2021 return true; 2022 } 2023 2024 return false; 2025 } 2026 2027 static const Decl *getDefinition(const Decl *D) { 2028 if (const TagDecl *TD = dyn_cast<TagDecl>(D)) 2029 return TD->getDefinition(); 2030 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 2031 return VD->getDefinition(); 2032 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 2033 const FunctionDecl* Def; 2034 if (FD->hasBody(Def)) 2035 return Def; 2036 } 2037 return NULL; 2038 } 2039 2040 static bool hasAttribute(const Decl *D, attr::Kind Kind) { 2041 for (Decl::attr_iterator I = D->attr_begin(), E = D->attr_end(); 2042 I != E; ++I) { 2043 Attr *Attribute = *I; 2044 if (Attribute->getKind() == Kind) 2045 return true; 2046 } 2047 return false; 2048 } 2049 2050 /// checkNewAttributesAfterDef - If we already have a definition, check that 2051 /// there are no new attributes in this declaration. 2052 static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) { 2053 if (!New->hasAttrs()) 2054 return; 2055 2056 const Decl *Def = getDefinition(Old); 2057 if (!Def || Def == New) 2058 return; 2059 2060 AttrVec &NewAttributes = New->getAttrs(); 2061 for (unsigned I = 0, E = NewAttributes.size(); I != E;) { 2062 const Attr *NewAttribute = NewAttributes[I]; 2063 if (hasAttribute(Def, NewAttribute->getKind())) { 2064 ++I; 2065 continue; // regular attr merging will take care of validating this. 2066 } 2067 2068 if (isa<C11NoReturnAttr>(NewAttribute)) { 2069 // C's _Noreturn is allowed to be added to a function after it is defined. 2070 ++I; 2071 continue; 2072 } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) { 2073 if (AA->isAlignas()) { 2074 // C++11 [dcl.align]p6: 2075 // if any declaration of an entity has an alignment-specifier, 2076 // every defining declaration of that entity shall specify an 2077 // equivalent alignment. 2078 // C11 6.7.5/7: 2079 // If the definition of an object does not have an alignment 2080 // specifier, any other declaration of that object shall also 2081 // have no alignment specifier. 2082 S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition) 2083 << AA->isC11(); 2084 S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration) 2085 << AA->isC11(); 2086 NewAttributes.erase(NewAttributes.begin() + I); 2087 --E; 2088 continue; 2089 } 2090 } 2091 2092 S.Diag(NewAttribute->getLocation(), 2093 diag::warn_attribute_precede_definition); 2094 S.Diag(Def->getLocation(), diag::note_previous_definition); 2095 NewAttributes.erase(NewAttributes.begin() + I); 2096 --E; 2097 } 2098 } 2099 2100 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one. 2101 void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old, 2102 AvailabilityMergeKind AMK) { 2103 if (!Old->hasAttrs() && !New->hasAttrs()) 2104 return; 2105 2106 // attributes declared post-definition are currently ignored 2107 checkNewAttributesAfterDef(*this, New, Old); 2108 2109 if (!Old->hasAttrs()) 2110 return; 2111 2112 bool foundAny = New->hasAttrs(); 2113 2114 // Ensure that any moving of objects within the allocated map is done before 2115 // we process them. 2116 if (!foundAny) New->setAttrs(AttrVec()); 2117 2118 for (specific_attr_iterator<InheritableAttr> 2119 i = Old->specific_attr_begin<InheritableAttr>(), 2120 e = Old->specific_attr_end<InheritableAttr>(); 2121 i != e; ++i) { 2122 bool Override = false; 2123 // Ignore deprecated/unavailable/availability attributes if requested. 2124 if (isa<DeprecatedAttr>(*i) || 2125 isa<UnavailableAttr>(*i) || 2126 isa<AvailabilityAttr>(*i)) { 2127 switch (AMK) { 2128 case AMK_None: 2129 continue; 2130 2131 case AMK_Redeclaration: 2132 break; 2133 2134 case AMK_Override: 2135 Override = true; 2136 break; 2137 } 2138 } 2139 2140 if (mergeDeclAttribute(*this, New, *i, Override)) 2141 foundAny = true; 2142 } 2143 2144 if (mergeAlignedAttrs(*this, New, Old)) 2145 foundAny = true; 2146 2147 if (!foundAny) New->dropAttrs(); 2148 } 2149 2150 /// mergeParamDeclAttributes - Copy attributes from the old parameter 2151 /// to the new one. 2152 static void mergeParamDeclAttributes(ParmVarDecl *newDecl, 2153 const ParmVarDecl *oldDecl, 2154 Sema &S) { 2155 // C++11 [dcl.attr.depend]p2: 2156 // The first declaration of a function shall specify the 2157 // carries_dependency attribute for its declarator-id if any declaration 2158 // of the function specifies the carries_dependency attribute. 2159 if (newDecl->hasAttr<CarriesDependencyAttr>() && 2160 !oldDecl->hasAttr<CarriesDependencyAttr>()) { 2161 S.Diag(newDecl->getAttr<CarriesDependencyAttr>()->getLocation(), 2162 diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/; 2163 // Find the first declaration of the parameter. 2164 // FIXME: Should we build redeclaration chains for function parameters? 2165 const FunctionDecl *FirstFD = 2166 cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDeclaration(); 2167 const ParmVarDecl *FirstVD = 2168 FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex()); 2169 S.Diag(FirstVD->getLocation(), 2170 diag::note_carries_dependency_missing_first_decl) << 1/*Param*/; 2171 } 2172 2173 if (!oldDecl->hasAttrs()) 2174 return; 2175 2176 bool foundAny = newDecl->hasAttrs(); 2177 2178 // Ensure that any moving of objects within the allocated map is 2179 // done before we process them. 2180 if (!foundAny) newDecl->setAttrs(AttrVec()); 2181 2182 for (specific_attr_iterator<InheritableParamAttr> 2183 i = oldDecl->specific_attr_begin<InheritableParamAttr>(), 2184 e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { 2185 if (!DeclHasAttr(newDecl, *i)) { 2186 InheritableAttr *newAttr = 2187 cast<InheritableParamAttr>((*i)->clone(S.Context)); 2188 newAttr->setInherited(true); 2189 newDecl->addAttr(newAttr); 2190 foundAny = true; 2191 } 2192 } 2193 2194 if (!foundAny) newDecl->dropAttrs(); 2195 } 2196 2197 namespace { 2198 2199 /// Used in MergeFunctionDecl to keep track of function parameters in 2200 /// C. 2201 struct GNUCompatibleParamWarning { 2202 ParmVarDecl *OldParm; 2203 ParmVarDecl *NewParm; 2204 QualType PromotedType; 2205 }; 2206 2207 } 2208 2209 /// getSpecialMember - get the special member enum for a method. 2210 Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 2211 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 2212 if (Ctor->isDefaultConstructor()) 2213 return Sema::CXXDefaultConstructor; 2214 2215 if (Ctor->isCopyConstructor()) 2216 return Sema::CXXCopyConstructor; 2217 2218 if (Ctor->isMoveConstructor()) 2219 return Sema::CXXMoveConstructor; 2220 } else if (isa<CXXDestructorDecl>(MD)) { 2221 return Sema::CXXDestructor; 2222 } else if (MD->isCopyAssignmentOperator()) { 2223 return Sema::CXXCopyAssignment; 2224 } else if (MD->isMoveAssignmentOperator()) { 2225 return Sema::CXXMoveAssignment; 2226 } 2227 2228 return Sema::CXXInvalid; 2229 } 2230 2231 /// canRedefineFunction - checks if a function can be redefined. Currently, 2232 /// only extern inline functions can be redefined, and even then only in 2233 /// GNU89 mode. 2234 static bool canRedefineFunction(const FunctionDecl *FD, 2235 const LangOptions& LangOpts) { 2236 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) && 2237 !LangOpts.CPlusPlus && 2238 FD->isInlineSpecified() && 2239 FD->getStorageClass() == SC_Extern); 2240 } 2241 2242 /// Is the given calling convention the ABI default for the given 2243 /// declaration? 2244 static bool isABIDefaultCC(Sema &S, CallingConv CC, FunctionDecl *D) { 2245 CallingConv ABIDefaultCC; 2246 if (isa<CXXMethodDecl>(D) && cast<CXXMethodDecl>(D)->isInstance()) { 2247 ABIDefaultCC = S.Context.getDefaultCXXMethodCallConv(D->isVariadic()); 2248 } else { 2249 // Free C function or a static method. 2250 ABIDefaultCC = (S.Context.getLangOpts().MRTD ? CC_X86StdCall : CC_C); 2251 } 2252 return ABIDefaultCC == CC; 2253 } 2254 2255 template <typename T> 2256 static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) { 2257 const DeclContext *DC = Old->getDeclContext(); 2258 if (DC->isRecord()) 2259 return false; 2260 2261 LanguageLinkage OldLinkage = Old->getLanguageLinkage(); 2262 if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext()) 2263 return true; 2264 if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext()) 2265 return true; 2266 return false; 2267 } 2268 2269 /// MergeFunctionDecl - We just parsed a function 'New' from 2270 /// declarator D which has the same name and scope as a previous 2271 /// declaration 'Old'. Figure out how to resolve this situation, 2272 /// merging decls or emitting diagnostics as appropriate. 2273 /// 2274 /// In C++, New and Old must be declarations that are not 2275 /// overloaded. Use IsOverload to determine whether New and Old are 2276 /// overloaded, and to select the Old declaration that New should be 2277 /// merged with. 2278 /// 2279 /// Returns true if there was an error, false otherwise. 2280 bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, Scope *S) { 2281 // Verify the old decl was also a function. 2282 FunctionDecl *Old = 0; 2283 if (FunctionTemplateDecl *OldFunctionTemplate 2284 = dyn_cast<FunctionTemplateDecl>(OldD)) 2285 Old = OldFunctionTemplate->getTemplatedDecl(); 2286 else 2287 Old = dyn_cast<FunctionDecl>(OldD); 2288 if (!Old) { 2289 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 2290 if (New->getFriendObjectKind()) { 2291 Diag(New->getLocation(), diag::err_using_decl_friend); 2292 Diag(Shadow->getTargetDecl()->getLocation(), 2293 diag::note_using_decl_target); 2294 Diag(Shadow->getUsingDecl()->getLocation(), 2295 diag::note_using_decl) << 0; 2296 return true; 2297 } 2298 2299 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 2300 Diag(Shadow->getTargetDecl()->getLocation(), 2301 diag::note_using_decl_target); 2302 Diag(Shadow->getUsingDecl()->getLocation(), 2303 diag::note_using_decl) << 0; 2304 return true; 2305 } 2306 2307 Diag(New->getLocation(), diag::err_redefinition_different_kind) 2308 << New->getDeclName(); 2309 Diag(OldD->getLocation(), diag::note_previous_definition); 2310 return true; 2311 } 2312 2313 // If the old declaration is invalid, just give up here. 2314 if (Old->isInvalidDecl()) 2315 return true; 2316 2317 // Determine whether the previous declaration was a definition, 2318 // implicit declaration, or a declaration. 2319 diag::kind PrevDiag; 2320 if (Old->isThisDeclarationADefinition()) 2321 PrevDiag = diag::note_previous_definition; 2322 else if (Old->isImplicit()) 2323 PrevDiag = diag::note_previous_implicit_declaration; 2324 else 2325 PrevDiag = diag::note_previous_declaration; 2326 2327 QualType OldQType = Context.getCanonicalType(Old->getType()); 2328 QualType NewQType = Context.getCanonicalType(New->getType()); 2329 2330 // Don't complain about this if we're in GNU89 mode and the old function 2331 // is an extern inline function. 2332 // Don't complain about specializations. They are not supposed to have 2333 // storage classes. 2334 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 2335 New->getStorageClass() == SC_Static && 2336 Old->hasExternalFormalLinkage() && 2337 !New->getTemplateSpecializationInfo() && 2338 !canRedefineFunction(Old, getLangOpts())) { 2339 if (getLangOpts().MicrosoftExt) { 2340 Diag(New->getLocation(), diag::warn_static_non_static) << New; 2341 Diag(Old->getLocation(), PrevDiag); 2342 } else { 2343 Diag(New->getLocation(), diag::err_static_non_static) << New; 2344 Diag(Old->getLocation(), PrevDiag); 2345 return true; 2346 } 2347 } 2348 2349 // If a function is first declared with a calling convention, but is 2350 // later declared or defined without one, the second decl assumes the 2351 // calling convention of the first. 2352 // 2353 // It's OK if a function is first declared without a calling convention, 2354 // but is later declared or defined with the default calling convention. 2355 // 2356 // For the new decl, we have to look at the NON-canonical type to tell the 2357 // difference between a function that really doesn't have a calling 2358 // convention and one that is declared cdecl. That's because in 2359 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 2360 // because it is the default calling convention. 2361 // 2362 // Note also that we DO NOT return at this point, because we still have 2363 // other tests to run. 2364 const FunctionType *OldType = cast<FunctionType>(OldQType); 2365 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 2366 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 2367 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 2368 bool RequiresAdjustment = false; 2369 if (OldTypeInfo.getCC() == NewTypeInfo.getCC()) { 2370 // Fast path: nothing to do. 2371 2372 // Inherit the CC from the previous declaration if it was specified 2373 // there but not here. 2374 } else if (NewTypeInfo.getCC() == CC_Default) { 2375 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 2376 RequiresAdjustment = true; 2377 2378 // Don't complain about mismatches when the default CC is 2379 // effectively the same as the explict one. Only Old decl contains correct 2380 // information about storage class of CXXMethod. 2381 } else if (OldTypeInfo.getCC() == CC_Default && 2382 isABIDefaultCC(*this, NewTypeInfo.getCC(), Old)) { 2383 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 2384 RequiresAdjustment = true; 2385 2386 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 2387 NewTypeInfo.getCC())) { 2388 // Calling conventions really aren't compatible, so complain. 2389 Diag(New->getLocation(), diag::err_cconv_change) 2390 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 2391 << (OldTypeInfo.getCC() == CC_Default) 2392 << (OldTypeInfo.getCC() == CC_Default ? "" : 2393 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 2394 Diag(Old->getLocation(), diag::note_previous_declaration); 2395 return true; 2396 } 2397 2398 // FIXME: diagnose the other way around? 2399 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 2400 NewTypeInfo = NewTypeInfo.withNoReturn(true); 2401 RequiresAdjustment = true; 2402 } 2403 2404 // Merge regparm attribute. 2405 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() || 2406 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 2407 if (NewTypeInfo.getHasRegParm()) { 2408 Diag(New->getLocation(), diag::err_regparm_mismatch) 2409 << NewType->getRegParmType() 2410 << OldType->getRegParmType(); 2411 Diag(Old->getLocation(), diag::note_previous_declaration); 2412 return true; 2413 } 2414 2415 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 2416 RequiresAdjustment = true; 2417 } 2418 2419 // Merge ns_returns_retained attribute. 2420 if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) { 2421 if (NewTypeInfo.getProducesResult()) { 2422 Diag(New->getLocation(), diag::err_returns_retained_mismatch); 2423 Diag(Old->getLocation(), diag::note_previous_declaration); 2424 return true; 2425 } 2426 2427 NewTypeInfo = NewTypeInfo.withProducesResult(true); 2428 RequiresAdjustment = true; 2429 } 2430 2431 if (RequiresAdjustment) { 2432 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 2433 New->setType(QualType(NewType, 0)); 2434 NewQType = Context.getCanonicalType(New->getType()); 2435 } 2436 2437 // If this redeclaration makes the function inline, we may need to add it to 2438 // UndefinedButUsed. 2439 if (!Old->isInlined() && New->isInlined() && 2440 !New->hasAttr<GNUInlineAttr>() && 2441 (getLangOpts().CPlusPlus || !getLangOpts().GNUInline) && 2442 Old->isUsed(false) && 2443 !Old->isDefined() && !New->isThisDeclarationADefinition()) 2444 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(), 2445 SourceLocation())); 2446 2447 // If this redeclaration makes it newly gnu_inline, we don't want to warn 2448 // about it. 2449 if (New->hasAttr<GNUInlineAttr>() && 2450 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) { 2451 UndefinedButUsed.erase(Old->getCanonicalDecl()); 2452 } 2453 2454 if (getLangOpts().CPlusPlus) { 2455 // (C++98 13.1p2): 2456 // Certain function declarations cannot be overloaded: 2457 // -- Function declarations that differ only in the return type 2458 // cannot be overloaded. 2459 2460 // Go back to the type source info to compare the declared return types, 2461 // per C++1y [dcl.type.auto]p??: 2462 // Redeclarations or specializations of a function or function template 2463 // with a declared return type that uses a placeholder type shall also 2464 // use that placeholder, not a deduced type. 2465 QualType OldDeclaredReturnType = (Old->getTypeSourceInfo() 2466 ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>() 2467 : OldType)->getResultType(); 2468 QualType NewDeclaredReturnType = (New->getTypeSourceInfo() 2469 ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>() 2470 : NewType)->getResultType(); 2471 QualType ResQT; 2472 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType)) { 2473 if (NewDeclaredReturnType->isObjCObjectPointerType() && 2474 OldDeclaredReturnType->isObjCObjectPointerType()) 2475 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 2476 if (ResQT.isNull()) { 2477 if (New->isCXXClassMember() && New->isOutOfLine()) 2478 Diag(New->getLocation(), 2479 diag::err_member_def_does_not_match_ret_type) << New; 2480 else 2481 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 2482 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 2483 return true; 2484 } 2485 else 2486 NewQType = ResQT; 2487 } 2488 2489 QualType OldReturnType = OldType->getResultType(); 2490 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 2491 if (OldReturnType != NewReturnType) { 2492 // If this function has a deduced return type and has already been 2493 // defined, copy the deduced value from the old declaration. 2494 AutoType *OldAT = Old->getResultType()->getContainedAutoType(); 2495 if (OldAT && OldAT->isDeduced()) { 2496 New->setType(SubstAutoType(New->getType(), OldAT->getDeducedType())); 2497 NewQType = Context.getCanonicalType( 2498 SubstAutoType(NewQType, OldAT->getDeducedType())); 2499 } 2500 } 2501 2502 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old); 2503 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New); 2504 if (OldMethod && NewMethod) { 2505 // Preserve triviality. 2506 NewMethod->setTrivial(OldMethod->isTrivial()); 2507 2508 // MSVC allows explicit template specialization at class scope: 2509 // 2 CXMethodDecls referring to the same function will be injected. 2510 // We don't want a redeclartion error. 2511 bool IsClassScopeExplicitSpecialization = 2512 OldMethod->isFunctionTemplateSpecialization() && 2513 NewMethod->isFunctionTemplateSpecialization(); 2514 bool isFriend = NewMethod->getFriendObjectKind(); 2515 2516 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() && 2517 !IsClassScopeExplicitSpecialization) { 2518 // -- Member function declarations with the same name and the 2519 // same parameter types cannot be overloaded if any of them 2520 // is a static member function declaration. 2521 if (OldMethod->isStatic() != NewMethod->isStatic()) { 2522 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 2523 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 2524 return true; 2525 } 2526 2527 // C++ [class.mem]p1: 2528 // [...] A member shall not be declared twice in the 2529 // member-specification, except that a nested class or member 2530 // class template can be declared and then later defined. 2531 if (ActiveTemplateInstantiations.empty()) { 2532 unsigned NewDiag; 2533 if (isa<CXXConstructorDecl>(OldMethod)) 2534 NewDiag = diag::err_constructor_redeclared; 2535 else if (isa<CXXDestructorDecl>(NewMethod)) 2536 NewDiag = diag::err_destructor_redeclared; 2537 else if (isa<CXXConversionDecl>(NewMethod)) 2538 NewDiag = diag::err_conv_function_redeclared; 2539 else 2540 NewDiag = diag::err_member_redeclared; 2541 2542 Diag(New->getLocation(), NewDiag); 2543 } else { 2544 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation) 2545 << New << New->getType(); 2546 } 2547 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 2548 2549 // Complain if this is an explicit declaration of a special 2550 // member that was initially declared implicitly. 2551 // 2552 // As an exception, it's okay to befriend such methods in order 2553 // to permit the implicit constructor/destructor/operator calls. 2554 } else if (OldMethod->isImplicit()) { 2555 if (isFriend) { 2556 NewMethod->setImplicit(); 2557 } else { 2558 Diag(NewMethod->getLocation(), 2559 diag::err_definition_of_implicitly_declared_member) 2560 << New << getSpecialMember(OldMethod); 2561 return true; 2562 } 2563 } else if (OldMethod->isExplicitlyDefaulted() && !isFriend) { 2564 Diag(NewMethod->getLocation(), 2565 diag::err_definition_of_explicitly_defaulted_member) 2566 << getSpecialMember(OldMethod); 2567 return true; 2568 } 2569 } 2570 2571 // C++11 [dcl.attr.noreturn]p1: 2572 // The first declaration of a function shall specify the noreturn 2573 // attribute if any declaration of that function specifies the noreturn 2574 // attribute. 2575 if (New->hasAttr<CXX11NoReturnAttr>() && 2576 !Old->hasAttr<CXX11NoReturnAttr>()) { 2577 Diag(New->getAttr<CXX11NoReturnAttr>()->getLocation(), 2578 diag::err_noreturn_missing_on_first_decl); 2579 Diag(Old->getFirstDeclaration()->getLocation(), 2580 diag::note_noreturn_missing_first_decl); 2581 } 2582 2583 // C++11 [dcl.attr.depend]p2: 2584 // The first declaration of a function shall specify the 2585 // carries_dependency attribute for its declarator-id if any declaration 2586 // of the function specifies the carries_dependency attribute. 2587 if (New->hasAttr<CarriesDependencyAttr>() && 2588 !Old->hasAttr<CarriesDependencyAttr>()) { 2589 Diag(New->getAttr<CarriesDependencyAttr>()->getLocation(), 2590 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/; 2591 Diag(Old->getFirstDeclaration()->getLocation(), 2592 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/; 2593 } 2594 2595 // (C++98 8.3.5p3): 2596 // All declarations for a function shall agree exactly in both the 2597 // return type and the parameter-type-list. 2598 // We also want to respect all the extended bits except noreturn. 2599 2600 // noreturn should now match unless the old type info didn't have it. 2601 QualType OldQTypeForComparison = OldQType; 2602 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 2603 assert(OldQType == QualType(OldType, 0)); 2604 const FunctionType *OldTypeForComparison 2605 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 2606 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 2607 assert(OldQTypeForComparison.isCanonical()); 2608 } 2609 2610 if (haveIncompatibleLanguageLinkages(Old, New)) { 2611 Diag(New->getLocation(), diag::err_different_language_linkage) << New; 2612 Diag(Old->getLocation(), PrevDiag); 2613 return true; 2614 } 2615 2616 if (OldQTypeForComparison == NewQType) 2617 return MergeCompatibleFunctionDecls(New, Old, S); 2618 2619 // Fall through for conflicting redeclarations and redefinitions. 2620 } 2621 2622 // C: Function types need to be compatible, not identical. This handles 2623 // duplicate function decls like "void f(int); void f(enum X);" properly. 2624 if (!getLangOpts().CPlusPlus && 2625 Context.typesAreCompatible(OldQType, NewQType)) { 2626 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 2627 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 2628 const FunctionProtoType *OldProto = 0; 2629 if (isa<FunctionNoProtoType>(NewFuncType) && 2630 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 2631 // The old declaration provided a function prototype, but the 2632 // new declaration does not. Merge in the prototype. 2633 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 2634 SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 2635 OldProto->arg_type_end()); 2636 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 2637 ParamTypes, 2638 OldProto->getExtProtoInfo()); 2639 New->setType(NewQType); 2640 New->setHasInheritedPrototype(); 2641 2642 // Synthesize a parameter for each argument type. 2643 SmallVector<ParmVarDecl*, 16> Params; 2644 for (FunctionProtoType::arg_type_iterator 2645 ParamType = OldProto->arg_type_begin(), 2646 ParamEnd = OldProto->arg_type_end(); 2647 ParamType != ParamEnd; ++ParamType) { 2648 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 2649 SourceLocation(), 2650 SourceLocation(), 0, 2651 *ParamType, /*TInfo=*/0, 2652 SC_None, 2653 0); 2654 Param->setScopeInfo(0, Params.size()); 2655 Param->setImplicit(); 2656 Params.push_back(Param); 2657 } 2658 2659 New->setParams(Params); 2660 } 2661 2662 return MergeCompatibleFunctionDecls(New, Old, S); 2663 } 2664 2665 // GNU C permits a K&R definition to follow a prototype declaration 2666 // if the declared types of the parameters in the K&R definition 2667 // match the types in the prototype declaration, even when the 2668 // promoted types of the parameters from the K&R definition differ 2669 // from the types in the prototype. GCC then keeps the types from 2670 // the prototype. 2671 // 2672 // If a variadic prototype is followed by a non-variadic K&R definition, 2673 // the K&R definition becomes variadic. This is sort of an edge case, but 2674 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 2675 // C99 6.9.1p8. 2676 if (!getLangOpts().CPlusPlus && 2677 Old->hasPrototype() && !New->hasPrototype() && 2678 New->getType()->getAs<FunctionProtoType>() && 2679 Old->getNumParams() == New->getNumParams()) { 2680 SmallVector<QualType, 16> ArgTypes; 2681 SmallVector<GNUCompatibleParamWarning, 16> Warnings; 2682 const FunctionProtoType *OldProto 2683 = Old->getType()->getAs<FunctionProtoType>(); 2684 const FunctionProtoType *NewProto 2685 = New->getType()->getAs<FunctionProtoType>(); 2686 2687 // Determine whether this is the GNU C extension. 2688 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 2689 NewProto->getResultType()); 2690 bool LooseCompatible = !MergedReturn.isNull(); 2691 for (unsigned Idx = 0, End = Old->getNumParams(); 2692 LooseCompatible && Idx != End; ++Idx) { 2693 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 2694 ParmVarDecl *NewParm = New->getParamDecl(Idx); 2695 if (Context.typesAreCompatible(OldParm->getType(), 2696 NewProto->getArgType(Idx))) { 2697 ArgTypes.push_back(NewParm->getType()); 2698 } else if (Context.typesAreCompatible(OldParm->getType(), 2699 NewParm->getType(), 2700 /*CompareUnqualified=*/true)) { 2701 GNUCompatibleParamWarning Warn 2702 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 2703 Warnings.push_back(Warn); 2704 ArgTypes.push_back(NewParm->getType()); 2705 } else 2706 LooseCompatible = false; 2707 } 2708 2709 if (LooseCompatible) { 2710 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 2711 Diag(Warnings[Warn].NewParm->getLocation(), 2712 diag::ext_param_promoted_not_compatible_with_prototype) 2713 << Warnings[Warn].PromotedType 2714 << Warnings[Warn].OldParm->getType(); 2715 if (Warnings[Warn].OldParm->getLocation().isValid()) 2716 Diag(Warnings[Warn].OldParm->getLocation(), 2717 diag::note_previous_declaration); 2718 } 2719 2720 New->setType(Context.getFunctionType(MergedReturn, ArgTypes, 2721 OldProto->getExtProtoInfo())); 2722 return MergeCompatibleFunctionDecls(New, Old, S); 2723 } 2724 2725 // Fall through to diagnose conflicting types. 2726 } 2727 2728 // A function that has already been declared has been redeclared or 2729 // defined with a different type; show an appropriate diagnostic. 2730 2731 // If the previous declaration was an implicitly-generated builtin 2732 // declaration, then at the very least we should use a specialized note. 2733 unsigned BuiltinID; 2734 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) { 2735 // If it's actually a library-defined builtin function like 'malloc' 2736 // or 'printf', just warn about the incompatible redeclaration. 2737 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2738 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 2739 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 2740 << Old << Old->getType(); 2741 2742 // If this is a global redeclaration, just forget hereafter 2743 // about the "builtin-ness" of the function. 2744 // 2745 // Doing this for local extern declarations is problematic. If 2746 // the builtin declaration remains visible, a second invalid 2747 // local declaration will produce a hard error; if it doesn't 2748 // remain visible, a single bogus local redeclaration (which is 2749 // actually only a warning) could break all the downstream code. 2750 if (!New->getDeclContext()->isFunctionOrMethod()) 2751 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 2752 2753 return false; 2754 } 2755 2756 PrevDiag = diag::note_previous_builtin_declaration; 2757 } 2758 2759 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 2760 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 2761 return true; 2762 } 2763 2764 /// \brief Completes the merge of two function declarations that are 2765 /// known to be compatible. 2766 /// 2767 /// This routine handles the merging of attributes and other 2768 /// properties of function declarations form the old declaration to 2769 /// the new declaration, once we know that New is in fact a 2770 /// redeclaration of Old. 2771 /// 2772 /// \returns false 2773 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old, 2774 Scope *S) { 2775 // Merge the attributes 2776 mergeDeclAttributes(New, Old); 2777 2778 // Merge "pure" flag. 2779 if (Old->isPure()) 2780 New->setPure(); 2781 2782 // Merge "used" flag. 2783 if (Old->isUsed(false)) 2784 New->setUsed(); 2785 2786 // Merge attributes from the parameters. These can mismatch with K&R 2787 // declarations. 2788 if (New->getNumParams() == Old->getNumParams()) 2789 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 2790 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 2791 *this); 2792 2793 if (getLangOpts().CPlusPlus) 2794 return MergeCXXFunctionDecl(New, Old, S); 2795 2796 // Merge the function types so the we get the composite types for the return 2797 // and argument types. 2798 QualType Merged = Context.mergeTypes(Old->getType(), New->getType()); 2799 if (!Merged.isNull()) 2800 New->setType(Merged); 2801 2802 return false; 2803 } 2804 2805 2806 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 2807 ObjCMethodDecl *oldMethod) { 2808 2809 // Merge the attributes, including deprecated/unavailable 2810 AvailabilityMergeKind MergeKind = 2811 isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration 2812 : AMK_Override; 2813 mergeDeclAttributes(newMethod, oldMethod, MergeKind); 2814 2815 // Merge attributes from the parameters. 2816 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(), 2817 oe = oldMethod->param_end(); 2818 for (ObjCMethodDecl::param_iterator 2819 ni = newMethod->param_begin(), ne = newMethod->param_end(); 2820 ni != ne && oi != oe; ++ni, ++oi) 2821 mergeParamDeclAttributes(*ni, *oi, *this); 2822 2823 CheckObjCMethodOverride(newMethod, oldMethod); 2824 } 2825 2826 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and 2827 /// scope as a previous declaration 'Old'. Figure out how to merge their types, 2828 /// emitting diagnostics as appropriate. 2829 /// 2830 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 2831 /// to here in AddInitializerToDecl. We can't check them before the initializer 2832 /// is attached. 2833 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old, bool OldWasHidden) { 2834 if (New->isInvalidDecl() || Old->isInvalidDecl()) 2835 return; 2836 2837 QualType MergedT; 2838 if (getLangOpts().CPlusPlus) { 2839 if (New->getType()->isUndeducedType()) { 2840 // We don't know what the new type is until the initializer is attached. 2841 return; 2842 } else if (Context.hasSameType(New->getType(), Old->getType())) { 2843 // These could still be something that needs exception specs checked. 2844 return MergeVarDeclExceptionSpecs(New, Old); 2845 } 2846 // C++ [basic.link]p10: 2847 // [...] the types specified by all declarations referring to a given 2848 // object or function shall be identical, except that declarations for an 2849 // array object can specify array types that differ by the presence or 2850 // absence of a major array bound (8.3.4). 2851 else if (Old->getType()->isIncompleteArrayType() && 2852 New->getType()->isArrayType()) { 2853 const ArrayType *OldArray = Context.getAsArrayType(Old->getType()); 2854 const ArrayType *NewArray = Context.getAsArrayType(New->getType()); 2855 if (Context.hasSameType(OldArray->getElementType(), 2856 NewArray->getElementType())) 2857 MergedT = New->getType(); 2858 } else if (Old->getType()->isArrayType() && 2859 New->getType()->isIncompleteArrayType()) { 2860 const ArrayType *OldArray = Context.getAsArrayType(Old->getType()); 2861 const ArrayType *NewArray = Context.getAsArrayType(New->getType()); 2862 if (Context.hasSameType(OldArray->getElementType(), 2863 NewArray->getElementType())) 2864 MergedT = Old->getType(); 2865 } else if (New->getType()->isObjCObjectPointerType() 2866 && Old->getType()->isObjCObjectPointerType()) { 2867 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 2868 Old->getType()); 2869 } 2870 } else { 2871 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 2872 } 2873 if (MergedT.isNull()) { 2874 Diag(New->getLocation(), diag::err_redefinition_different_type) 2875 << New->getDeclName() << New->getType() << Old->getType(); 2876 Diag(Old->getLocation(), diag::note_previous_definition); 2877 return New->setInvalidDecl(); 2878 } 2879 2880 // Don't actually update the type on the new declaration if the old 2881 // declaration was a extern declaration in a different scope. 2882 if (!OldWasHidden) 2883 New->setType(MergedT); 2884 } 2885 2886 /// MergeVarDecl - We just parsed a variable 'New' which has the same name 2887 /// and scope as a previous declaration 'Old'. Figure out how to resolve this 2888 /// situation, merging decls or emitting diagnostics as appropriate. 2889 /// 2890 /// Tentative definition rules (C99 6.9.2p2) are checked by 2891 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 2892 /// definitions here, since the initializer hasn't been attached. 2893 /// 2894 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous, 2895 bool PreviousWasHidden) { 2896 // If the new decl is already invalid, don't do any other checking. 2897 if (New->isInvalidDecl()) 2898 return; 2899 2900 // Verify the old decl was also a variable. 2901 VarDecl *Old = 0; 2902 if (!Previous.isSingleResult() || 2903 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 2904 Diag(New->getLocation(), diag::err_redefinition_different_kind) 2905 << New->getDeclName(); 2906 Diag(Previous.getRepresentativeDecl()->getLocation(), 2907 diag::note_previous_definition); 2908 return New->setInvalidDecl(); 2909 } 2910 2911 if (!shouldLinkPossiblyHiddenDecl(Old, New)) 2912 return; 2913 2914 // C++ [class.mem]p1: 2915 // A member shall not be declared twice in the member-specification [...] 2916 // 2917 // Here, we need only consider static data members. 2918 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 2919 Diag(New->getLocation(), diag::err_duplicate_member) 2920 << New->getIdentifier(); 2921 Diag(Old->getLocation(), diag::note_previous_declaration); 2922 New->setInvalidDecl(); 2923 } 2924 2925 mergeDeclAttributes(New, Old); 2926 // Warn if an already-declared variable is made a weak_import in a subsequent 2927 // declaration 2928 if (New->getAttr<WeakImportAttr>() && 2929 Old->getStorageClass() == SC_None && 2930 !Old->getAttr<WeakImportAttr>()) { 2931 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName(); 2932 Diag(Old->getLocation(), diag::note_previous_definition); 2933 // Remove weak_import attribute on new declaration. 2934 New->dropAttr<WeakImportAttr>(); 2935 } 2936 2937 // Merge the types. 2938 MergeVarDeclTypes(New, Old, PreviousWasHidden); 2939 if (New->isInvalidDecl()) 2940 return; 2941 2942 // [dcl.stc]p8: Check if we have a non-static decl followed by a static. 2943 if (New->getStorageClass() == SC_Static && 2944 !New->isStaticDataMember() && 2945 Old->hasExternalFormalLinkage()) { 2946 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 2947 Diag(Old->getLocation(), diag::note_previous_definition); 2948 return New->setInvalidDecl(); 2949 } 2950 // C99 6.2.2p4: 2951 // For an identifier declared with the storage-class specifier 2952 // extern in a scope in which a prior declaration of that 2953 // identifier is visible,23) if the prior declaration specifies 2954 // internal or external linkage, the linkage of the identifier at 2955 // the later declaration is the same as the linkage specified at 2956 // the prior declaration. If no prior declaration is visible, or 2957 // if the prior declaration specifies no linkage, then the 2958 // identifier has external linkage. 2959 if (New->hasExternalStorage() && Old->hasLinkage()) 2960 /* Okay */; 2961 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static && 2962 !New->isStaticDataMember() && 2963 Old->getCanonicalDecl()->getStorageClass() == SC_Static) { 2964 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 2965 Diag(Old->getLocation(), diag::note_previous_definition); 2966 return New->setInvalidDecl(); 2967 } 2968 2969 // Check if extern is followed by non-extern and vice-versa. 2970 if (New->hasExternalStorage() && 2971 !Old->hasLinkage() && Old->isLocalVarDecl()) { 2972 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 2973 Diag(Old->getLocation(), diag::note_previous_definition); 2974 return New->setInvalidDecl(); 2975 } 2976 if (Old->hasLinkage() && New->isLocalVarDecl() && 2977 !New->hasExternalStorage()) { 2978 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 2979 Diag(Old->getLocation(), diag::note_previous_definition); 2980 return New->setInvalidDecl(); 2981 } 2982 2983 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 2984 2985 // FIXME: The test for external storage here seems wrong? We still 2986 // need to check for mismatches. 2987 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 2988 // Don't complain about out-of-line definitions of static members. 2989 !(Old->getLexicalDeclContext()->isRecord() && 2990 !New->getLexicalDeclContext()->isRecord())) { 2991 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 2992 Diag(Old->getLocation(), diag::note_previous_definition); 2993 return New->setInvalidDecl(); 2994 } 2995 2996 if (New->getTLSKind() != Old->getTLSKind()) { 2997 if (!Old->getTLSKind()) { 2998 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 2999 Diag(Old->getLocation(), diag::note_previous_declaration); 3000 } else if (!New->getTLSKind()) { 3001 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 3002 Diag(Old->getLocation(), diag::note_previous_declaration); 3003 } else { 3004 // Do not allow redeclaration to change the variable between requiring 3005 // static and dynamic initialization. 3006 // FIXME: GCC allows this, but uses the TLS keyword on the first 3007 // declaration to determine the kind. Do we need to be compatible here? 3008 Diag(New->getLocation(), diag::err_thread_thread_different_kind) 3009 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic); 3010 Diag(Old->getLocation(), diag::note_previous_declaration); 3011 } 3012 } 3013 3014 // C++ doesn't have tentative definitions, so go right ahead and check here. 3015 const VarDecl *Def; 3016 if (getLangOpts().CPlusPlus && 3017 New->isThisDeclarationADefinition() == VarDecl::Definition && 3018 (Def = Old->getDefinition())) { 3019 Diag(New->getLocation(), diag::err_redefinition) << New; 3020 Diag(Def->getLocation(), diag::note_previous_definition); 3021 New->setInvalidDecl(); 3022 return; 3023 } 3024 3025 if (haveIncompatibleLanguageLinkages(Old, New)) { 3026 Diag(New->getLocation(), diag::err_different_language_linkage) << New; 3027 Diag(Old->getLocation(), diag::note_previous_definition); 3028 New->setInvalidDecl(); 3029 return; 3030 } 3031 3032 // Merge "used" flag. 3033 if (Old->isUsed(false)) 3034 New->setUsed(); 3035 3036 // Keep a chain of previous declarations. 3037 New->setPreviousDeclaration(Old); 3038 3039 // Inherit access appropriately. 3040 New->setAccess(Old->getAccess()); 3041 } 3042 3043 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 3044 /// no declarator (e.g. "struct foo;") is parsed. 3045 Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 3046 DeclSpec &DS) { 3047 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg()); 3048 } 3049 3050 static void HandleTagNumbering(Sema &S, const TagDecl *Tag) { 3051 if (isa<CXXRecordDecl>(Tag->getParent())) { 3052 // If this tag is the direct child of a class, number it if 3053 // it is anonymous. 3054 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl()) 3055 return; 3056 MangleNumberingContext &MCtx = 3057 S.Context.getManglingNumberContext(Tag->getParent()); 3058 S.Context.setManglingNumber(Tag, MCtx.getManglingNumber(Tag)); 3059 return; 3060 } 3061 3062 // If this tag isn't a direct child of a class, number it if it is local. 3063 Decl *ManglingContextDecl; 3064 if (MangleNumberingContext *MCtx = 3065 S.getCurrentMangleNumberContext(Tag->getDeclContext(), 3066 ManglingContextDecl)) { 3067 S.Context.setManglingNumber(Tag, MCtx->getManglingNumber(Tag)); 3068 } 3069 } 3070 3071 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 3072 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template 3073 /// parameters to cope with template friend declarations. 3074 Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 3075 DeclSpec &DS, 3076 MultiTemplateParamsArg TemplateParams, 3077 bool IsExplicitInstantiation) { 3078 Decl *TagD = 0; 3079 TagDecl *Tag = 0; 3080 if (DS.getTypeSpecType() == DeclSpec::TST_class || 3081 DS.getTypeSpecType() == DeclSpec::TST_struct || 3082 DS.getTypeSpecType() == DeclSpec::TST_interface || 3083 DS.getTypeSpecType() == DeclSpec::TST_union || 3084 DS.getTypeSpecType() == DeclSpec::TST_enum) { 3085 TagD = DS.getRepAsDecl(); 3086 3087 if (!TagD) // We probably had an error 3088 return 0; 3089 3090 // Note that the above type specs guarantee that the 3091 // type rep is a Decl, whereas in many of the others 3092 // it's a Type. 3093 if (isa<TagDecl>(TagD)) 3094 Tag = cast<TagDecl>(TagD); 3095 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD)) 3096 Tag = CTD->getTemplatedDecl(); 3097 } 3098 3099 if (Tag) { 3100 HandleTagNumbering(*this, Tag); 3101 Tag->setFreeStanding(); 3102 if (Tag->isInvalidDecl()) 3103 return Tag; 3104 } 3105 3106 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 3107 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 3108 // or incomplete types shall not be restrict-qualified." 3109 if (TypeQuals & DeclSpec::TQ_restrict) 3110 Diag(DS.getRestrictSpecLoc(), 3111 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 3112 << DS.getSourceRange(); 3113 } 3114 3115 if (DS.isConstexprSpecified()) { 3116 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations 3117 // and definitions of functions and variables. 3118 if (Tag) 3119 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag) 3120 << (DS.getTypeSpecType() == DeclSpec::TST_class ? 0 : 3121 DS.getTypeSpecType() == DeclSpec::TST_struct ? 1 : 3122 DS.getTypeSpecType() == DeclSpec::TST_interface ? 2 : 3123 DS.getTypeSpecType() == DeclSpec::TST_union ? 3 : 4); 3124 else 3125 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators); 3126 // Don't emit warnings after this error. 3127 return TagD; 3128 } 3129 3130 DiagnoseFunctionSpecifiers(DS); 3131 3132 if (DS.isFriendSpecified()) { 3133 // If we're dealing with a decl but not a TagDecl, assume that 3134 // whatever routines created it handled the friendship aspect. 3135 if (TagD && !Tag) 3136 return 0; 3137 return ActOnFriendTypeDecl(S, DS, TemplateParams); 3138 } 3139 3140 CXXScopeSpec &SS = DS.getTypeSpecScope(); 3141 bool IsExplicitSpecialization = 3142 !TemplateParams.empty() && TemplateParams.back()->size() == 0; 3143 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() && 3144 !IsExplicitInstantiation && !IsExplicitSpecialization) { 3145 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a 3146 // nested-name-specifier unless it is an explicit instantiation 3147 // or an explicit specialization. 3148 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either. 3149 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier) 3150 << (DS.getTypeSpecType() == DeclSpec::TST_class ? 0 : 3151 DS.getTypeSpecType() == DeclSpec::TST_struct ? 1 : 3152 DS.getTypeSpecType() == DeclSpec::TST_interface ? 2 : 3153 DS.getTypeSpecType() == DeclSpec::TST_union ? 3 : 4) 3154 << SS.getRange(); 3155 return 0; 3156 } 3157 3158 // Track whether this decl-specifier declares anything. 3159 bool DeclaresAnything = true; 3160 3161 // Handle anonymous struct definitions. 3162 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 3163 if (!Record->getDeclName() && Record->isCompleteDefinition() && 3164 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 3165 if (getLangOpts().CPlusPlus || 3166 Record->getDeclContext()->isRecord()) 3167 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 3168 3169 DeclaresAnything = false; 3170 } 3171 } 3172 3173 // Check for Microsoft C extension: anonymous struct member. 3174 if (getLangOpts().MicrosoftExt && !getLangOpts().CPlusPlus && 3175 CurContext->isRecord() && 3176 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 3177 // Handle 2 kinds of anonymous struct: 3178 // struct STRUCT; 3179 // and 3180 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 3181 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 3182 if ((Record && Record->getDeclName() && !Record->isCompleteDefinition()) || 3183 (DS.getTypeSpecType() == DeclSpec::TST_typename && 3184 DS.getRepAsType().get()->isStructureType())) { 3185 Diag(DS.getLocStart(), diag::ext_ms_anonymous_struct) 3186 << DS.getSourceRange(); 3187 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 3188 } 3189 } 3190 3191 // Skip all the checks below if we have a type error. 3192 if (DS.getTypeSpecType() == DeclSpec::TST_error || 3193 (TagD && TagD->isInvalidDecl())) 3194 return TagD; 3195 3196 if (getLangOpts().CPlusPlus && 3197 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 3198 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 3199 if (Enum->enumerator_begin() == Enum->enumerator_end() && 3200 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 3201 DeclaresAnything = false; 3202 3203 if (!DS.isMissingDeclaratorOk()) { 3204 // Customize diagnostic for a typedef missing a name. 3205 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) 3206 Diag(DS.getLocStart(), diag::ext_typedef_without_a_name) 3207 << DS.getSourceRange(); 3208 else 3209 DeclaresAnything = false; 3210 } 3211 3212 if (DS.isModulePrivateSpecified() && 3213 Tag && Tag->getDeclContext()->isFunctionOrMethod()) 3214 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class) 3215 << Tag->getTagKind() 3216 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc()); 3217 3218 ActOnDocumentableDecl(TagD); 3219 3220 // C 6.7/2: 3221 // A declaration [...] shall declare at least a declarator [...], a tag, 3222 // or the members of an enumeration. 3223 // C++ [dcl.dcl]p3: 3224 // [If there are no declarators], and except for the declaration of an 3225 // unnamed bit-field, the decl-specifier-seq shall introduce one or more 3226 // names into the program, or shall redeclare a name introduced by a 3227 // previous declaration. 3228 if (!DeclaresAnything) { 3229 // In C, we allow this as a (popular) extension / bug. Don't bother 3230 // producing further diagnostics for redundant qualifiers after this. 3231 Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange(); 3232 return TagD; 3233 } 3234 3235 // C++ [dcl.stc]p1: 3236 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the 3237 // init-declarator-list of the declaration shall not be empty. 3238 // C++ [dcl.fct.spec]p1: 3239 // If a cv-qualifier appears in a decl-specifier-seq, the 3240 // init-declarator-list of the declaration shall not be empty. 3241 // 3242 // Spurious qualifiers here appear to be valid in C. 3243 unsigned DiagID = diag::warn_standalone_specifier; 3244 if (getLangOpts().CPlusPlus) 3245 DiagID = diag::ext_standalone_specifier; 3246 3247 // Note that a linkage-specification sets a storage class, but 3248 // 'extern "C" struct foo;' is actually valid and not theoretically 3249 // useless. 3250 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) 3251 if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef) 3252 Diag(DS.getStorageClassSpecLoc(), DiagID) 3253 << DeclSpec::getSpecifierName(SCS); 3254 3255 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec()) 3256 Diag(DS.getThreadStorageClassSpecLoc(), DiagID) 3257 << DeclSpec::getSpecifierName(TSCS); 3258 if (DS.getTypeQualifiers()) { 3259 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 3260 Diag(DS.getConstSpecLoc(), DiagID) << "const"; 3261 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 3262 Diag(DS.getConstSpecLoc(), DiagID) << "volatile"; 3263 // Restrict is covered above. 3264 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic) 3265 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic"; 3266 } 3267 3268 // Warn about ignored type attributes, for example: 3269 // __attribute__((aligned)) struct A; 3270 // Attributes should be placed after tag to apply to type declaration. 3271 if (!DS.getAttributes().empty()) { 3272 DeclSpec::TST TypeSpecType = DS.getTypeSpecType(); 3273 if (TypeSpecType == DeclSpec::TST_class || 3274 TypeSpecType == DeclSpec::TST_struct || 3275 TypeSpecType == DeclSpec::TST_interface || 3276 TypeSpecType == DeclSpec::TST_union || 3277 TypeSpecType == DeclSpec::TST_enum) { 3278 AttributeList* attrs = DS.getAttributes().getList(); 3279 while (attrs) { 3280 Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored) 3281 << attrs->getName() 3282 << (TypeSpecType == DeclSpec::TST_class ? 0 : 3283 TypeSpecType == DeclSpec::TST_struct ? 1 : 3284 TypeSpecType == DeclSpec::TST_union ? 2 : 3285 TypeSpecType == DeclSpec::TST_interface ? 3 : 4); 3286 attrs = attrs->getNext(); 3287 } 3288 } 3289 } 3290 3291 return TagD; 3292 } 3293 3294 /// We are trying to inject an anonymous member into the given scope; 3295 /// check if there's an existing declaration that can't be overloaded. 3296 /// 3297 /// \return true if this is a forbidden redeclaration 3298 static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 3299 Scope *S, 3300 DeclContext *Owner, 3301 DeclarationName Name, 3302 SourceLocation NameLoc, 3303 unsigned diagnostic) { 3304 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 3305 Sema::ForRedeclaration); 3306 if (!SemaRef.LookupName(R, S)) return false; 3307 3308 if (R.getAsSingle<TagDecl>()) 3309 return false; 3310 3311 // Pick a representative declaration. 3312 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 3313 assert(PrevDecl && "Expected a non-null Decl"); 3314 3315 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 3316 return false; 3317 3318 SemaRef.Diag(NameLoc, diagnostic) << Name; 3319 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3320 3321 return true; 3322 } 3323 3324 /// InjectAnonymousStructOrUnionMembers - Inject the members of the 3325 /// anonymous struct or union AnonRecord into the owning context Owner 3326 /// and scope S. This routine will be invoked just after we realize 3327 /// that an unnamed union or struct is actually an anonymous union or 3328 /// struct, e.g., 3329 /// 3330 /// @code 3331 /// union { 3332 /// int i; 3333 /// float f; 3334 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 3335 /// // f into the surrounding scope.x 3336 /// @endcode 3337 /// 3338 /// This routine is recursive, injecting the names of nested anonymous 3339 /// structs/unions into the owning context and scope as well. 3340 static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 3341 DeclContext *Owner, 3342 RecordDecl *AnonRecord, 3343 AccessSpecifier AS, 3344 SmallVectorImpl<NamedDecl *> &Chaining, 3345 bool MSAnonStruct) { 3346 unsigned diagKind 3347 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 3348 : diag::err_anonymous_struct_member_redecl; 3349 3350 bool Invalid = false; 3351 3352 // Look every FieldDecl and IndirectFieldDecl with a name. 3353 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 3354 DEnd = AnonRecord->decls_end(); 3355 D != DEnd; ++D) { 3356 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 3357 cast<NamedDecl>(*D)->getDeclName()) { 3358 ValueDecl *VD = cast<ValueDecl>(*D); 3359 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 3360 VD->getLocation(), diagKind)) { 3361 // C++ [class.union]p2: 3362 // The names of the members of an anonymous union shall be 3363 // distinct from the names of any other entity in the 3364 // scope in which the anonymous union is declared. 3365 Invalid = true; 3366 } else { 3367 // C++ [class.union]p2: 3368 // For the purpose of name lookup, after the anonymous union 3369 // definition, the members of the anonymous union are 3370 // considered to have been defined in the scope in which the 3371 // anonymous union is declared. 3372 unsigned OldChainingSize = Chaining.size(); 3373 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 3374 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 3375 PE = IF->chain_end(); PI != PE; ++PI) 3376 Chaining.push_back(*PI); 3377 else 3378 Chaining.push_back(VD); 3379 3380 assert(Chaining.size() >= 2); 3381 NamedDecl **NamedChain = 3382 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 3383 for (unsigned i = 0; i < Chaining.size(); i++) 3384 NamedChain[i] = Chaining[i]; 3385 3386 IndirectFieldDecl* IndirectField = 3387 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 3388 VD->getIdentifier(), VD->getType(), 3389 NamedChain, Chaining.size()); 3390 3391 IndirectField->setAccess(AS); 3392 IndirectField->setImplicit(); 3393 SemaRef.PushOnScopeChains(IndirectField, S); 3394 3395 // That includes picking up the appropriate access specifier. 3396 if (AS != AS_none) IndirectField->setAccess(AS); 3397 3398 Chaining.resize(OldChainingSize); 3399 } 3400 } 3401 } 3402 3403 return Invalid; 3404 } 3405 3406 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 3407 /// a VarDecl::StorageClass. Any error reporting is up to the caller: 3408 /// illegal input values are mapped to SC_None. 3409 static StorageClass 3410 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) { 3411 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec(); 3412 assert(StorageClassSpec != DeclSpec::SCS_typedef && 3413 "Parser allowed 'typedef' as storage class VarDecl."); 3414 switch (StorageClassSpec) { 3415 case DeclSpec::SCS_unspecified: return SC_None; 3416 case DeclSpec::SCS_extern: 3417 if (DS.isExternInLinkageSpec()) 3418 return SC_None; 3419 return SC_Extern; 3420 case DeclSpec::SCS_static: return SC_Static; 3421 case DeclSpec::SCS_auto: return SC_Auto; 3422 case DeclSpec::SCS_register: return SC_Register; 3423 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 3424 // Illegal SCSs map to None: error reporting is up to the caller. 3425 case DeclSpec::SCS_mutable: // Fall through. 3426 case DeclSpec::SCS_typedef: return SC_None; 3427 } 3428 llvm_unreachable("unknown storage class specifier"); 3429 } 3430 3431 /// BuildAnonymousStructOrUnion - Handle the declaration of an 3432 /// anonymous structure or union. Anonymous unions are a C++ feature 3433 /// (C++ [class.union]) and a C11 feature; anonymous structures 3434 /// are a C11 feature and GNU C++ extension. 3435 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 3436 AccessSpecifier AS, 3437 RecordDecl *Record) { 3438 DeclContext *Owner = Record->getDeclContext(); 3439 3440 // Diagnose whether this anonymous struct/union is an extension. 3441 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11) 3442 Diag(Record->getLocation(), diag::ext_anonymous_union); 3443 else if (!Record->isUnion() && getLangOpts().CPlusPlus) 3444 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct); 3445 else if (!Record->isUnion() && !getLangOpts().C11) 3446 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct); 3447 3448 // C and C++ require different kinds of checks for anonymous 3449 // structs/unions. 3450 bool Invalid = false; 3451 if (getLangOpts().CPlusPlus) { 3452 const char* PrevSpec = 0; 3453 unsigned DiagID; 3454 if (Record->isUnion()) { 3455 // C++ [class.union]p6: 3456 // Anonymous unions declared in a named namespace or in the 3457 // global namespace shall be declared static. 3458 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 3459 (isa<TranslationUnitDecl>(Owner) || 3460 (isa<NamespaceDecl>(Owner) && 3461 cast<NamespaceDecl>(Owner)->getDeclName()))) { 3462 Diag(Record->getLocation(), diag::err_anonymous_union_not_static) 3463 << FixItHint::CreateInsertion(Record->getLocation(), "static "); 3464 3465 // Recover by adding 'static'. 3466 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(), 3467 PrevSpec, DiagID); 3468 } 3469 // C++ [class.union]p6: 3470 // A storage class is not allowed in a declaration of an 3471 // anonymous union in a class scope. 3472 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 3473 isa<RecordDecl>(Owner)) { 3474 Diag(DS.getStorageClassSpecLoc(), 3475 diag::err_anonymous_union_with_storage_spec) 3476 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc()); 3477 3478 // Recover by removing the storage specifier. 3479 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified, 3480 SourceLocation(), 3481 PrevSpec, DiagID); 3482 } 3483 } 3484 3485 // Ignore const/volatile/restrict qualifiers. 3486 if (DS.getTypeQualifiers()) { 3487 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 3488 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified) 3489 << Record->isUnion() << "const" 3490 << FixItHint::CreateRemoval(DS.getConstSpecLoc()); 3491 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 3492 Diag(DS.getVolatileSpecLoc(), 3493 diag::ext_anonymous_struct_union_qualified) 3494 << Record->isUnion() << "volatile" 3495 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc()); 3496 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict) 3497 Diag(DS.getRestrictSpecLoc(), 3498 diag::ext_anonymous_struct_union_qualified) 3499 << Record->isUnion() << "restrict" 3500 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc()); 3501 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic) 3502 Diag(DS.getAtomicSpecLoc(), 3503 diag::ext_anonymous_struct_union_qualified) 3504 << Record->isUnion() << "_Atomic" 3505 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc()); 3506 3507 DS.ClearTypeQualifiers(); 3508 } 3509 3510 // C++ [class.union]p2: 3511 // The member-specification of an anonymous union shall only 3512 // define non-static data members. [Note: nested types and 3513 // functions cannot be declared within an anonymous union. ] 3514 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 3515 MemEnd = Record->decls_end(); 3516 Mem != MemEnd; ++Mem) { 3517 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 3518 // C++ [class.union]p3: 3519 // An anonymous union shall not have private or protected 3520 // members (clause 11). 3521 assert(FD->getAccess() != AS_none); 3522 if (FD->getAccess() != AS_public) { 3523 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 3524 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 3525 Invalid = true; 3526 } 3527 3528 // C++ [class.union]p1 3529 // An object of a class with a non-trivial constructor, a non-trivial 3530 // copy constructor, a non-trivial destructor, or a non-trivial copy 3531 // assignment operator cannot be a member of a union, nor can an 3532 // array of such objects. 3533 if (CheckNontrivialField(FD)) 3534 Invalid = true; 3535 } else if ((*Mem)->isImplicit()) { 3536 // Any implicit members are fine. 3537 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 3538 // This is a type that showed up in an 3539 // elaborated-type-specifier inside the anonymous struct or 3540 // union, but which actually declares a type outside of the 3541 // anonymous struct or union. It's okay. 3542 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 3543 if (!MemRecord->isAnonymousStructOrUnion() && 3544 MemRecord->getDeclName()) { 3545 // Visual C++ allows type definition in anonymous struct or union. 3546 if (getLangOpts().MicrosoftExt) 3547 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 3548 << (int)Record->isUnion(); 3549 else { 3550 // This is a nested type declaration. 3551 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 3552 << (int)Record->isUnion(); 3553 Invalid = true; 3554 } 3555 } else { 3556 // This is an anonymous type definition within another anonymous type. 3557 // This is a popular extension, provided by Plan9, MSVC and GCC, but 3558 // not part of standard C++. 3559 Diag(MemRecord->getLocation(), 3560 diag::ext_anonymous_record_with_anonymous_type) 3561 << (int)Record->isUnion(); 3562 } 3563 } else if (isa<AccessSpecDecl>(*Mem)) { 3564 // Any access specifier is fine. 3565 } else { 3566 // We have something that isn't a non-static data 3567 // member. Complain about it. 3568 unsigned DK = diag::err_anonymous_record_bad_member; 3569 if (isa<TypeDecl>(*Mem)) 3570 DK = diag::err_anonymous_record_with_type; 3571 else if (isa<FunctionDecl>(*Mem)) 3572 DK = diag::err_anonymous_record_with_function; 3573 else if (isa<VarDecl>(*Mem)) 3574 DK = diag::err_anonymous_record_with_static; 3575 3576 // Visual C++ allows type definition in anonymous struct or union. 3577 if (getLangOpts().MicrosoftExt && 3578 DK == diag::err_anonymous_record_with_type) 3579 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 3580 << (int)Record->isUnion(); 3581 else { 3582 Diag((*Mem)->getLocation(), DK) 3583 << (int)Record->isUnion(); 3584 Invalid = true; 3585 } 3586 } 3587 } 3588 } 3589 3590 if (!Record->isUnion() && !Owner->isRecord()) { 3591 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 3592 << (int)getLangOpts().CPlusPlus; 3593 Invalid = true; 3594 } 3595 3596 // Mock up a declarator. 3597 Declarator Dc(DS, Declarator::MemberContext); 3598 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 3599 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 3600 3601 // Create a declaration for this anonymous struct/union. 3602 NamedDecl *Anon = 0; 3603 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 3604 Anon = FieldDecl::Create(Context, OwningClass, 3605 DS.getLocStart(), 3606 Record->getLocation(), 3607 /*IdentifierInfo=*/0, 3608 Context.getTypeDeclType(Record), 3609 TInfo, 3610 /*BitWidth=*/0, /*Mutable=*/false, 3611 /*InitStyle=*/ICIS_NoInit); 3612 Anon->setAccess(AS); 3613 if (getLangOpts().CPlusPlus) 3614 FieldCollector->Add(cast<FieldDecl>(Anon)); 3615 } else { 3616 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 3617 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS); 3618 if (SCSpec == DeclSpec::SCS_mutable) { 3619 // mutable can only appear on non-static class members, so it's always 3620 // an error here 3621 Diag(Record->getLocation(), diag::err_mutable_nonmember); 3622 Invalid = true; 3623 SC = SC_None; 3624 } 3625 3626 Anon = VarDecl::Create(Context, Owner, 3627 DS.getLocStart(), 3628 Record->getLocation(), /*IdentifierInfo=*/0, 3629 Context.getTypeDeclType(Record), 3630 TInfo, SC); 3631 3632 // Default-initialize the implicit variable. This initialization will be 3633 // trivial in almost all cases, except if a union member has an in-class 3634 // initializer: 3635 // union { int n = 0; }; 3636 ActOnUninitializedDecl(Anon, /*TypeMayContainAuto=*/false); 3637 } 3638 Anon->setImplicit(); 3639 3640 // Add the anonymous struct/union object to the current 3641 // context. We'll be referencing this object when we refer to one of 3642 // its members. 3643 Owner->addDecl(Anon); 3644 3645 // Inject the members of the anonymous struct/union into the owning 3646 // context and into the identifier resolver chain for name lookup 3647 // purposes. 3648 SmallVector<NamedDecl*, 2> Chain; 3649 Chain.push_back(Anon); 3650 3651 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 3652 Chain, false)) 3653 Invalid = true; 3654 3655 // Mark this as an anonymous struct/union type. Note that we do not 3656 // do this until after we have already checked and injected the 3657 // members of this anonymous struct/union type, because otherwise 3658 // the members could be injected twice: once by DeclContext when it 3659 // builds its lookup table, and once by 3660 // InjectAnonymousStructOrUnionMembers. 3661 Record->setAnonymousStructOrUnion(true); 3662 3663 if (Invalid) 3664 Anon->setInvalidDecl(); 3665 3666 return Anon; 3667 } 3668 3669 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 3670 /// Microsoft C anonymous structure. 3671 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 3672 /// Example: 3673 /// 3674 /// struct A { int a; }; 3675 /// struct B { struct A; int b; }; 3676 /// 3677 /// void foo() { 3678 /// B var; 3679 /// var.a = 3; 3680 /// } 3681 /// 3682 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 3683 RecordDecl *Record) { 3684 3685 // If there is no Record, get the record via the typedef. 3686 if (!Record) 3687 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 3688 3689 // Mock up a declarator. 3690 Declarator Dc(DS, Declarator::TypeNameContext); 3691 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 3692 assert(TInfo && "couldn't build declarator info for anonymous struct"); 3693 3694 // Create a declaration for this anonymous struct. 3695 NamedDecl* Anon = FieldDecl::Create(Context, 3696 cast<RecordDecl>(CurContext), 3697 DS.getLocStart(), 3698 DS.getLocStart(), 3699 /*IdentifierInfo=*/0, 3700 Context.getTypeDeclType(Record), 3701 TInfo, 3702 /*BitWidth=*/0, /*Mutable=*/false, 3703 /*InitStyle=*/ICIS_NoInit); 3704 Anon->setImplicit(); 3705 3706 // Add the anonymous struct object to the current context. 3707 CurContext->addDecl(Anon); 3708 3709 // Inject the members of the anonymous struct into the current 3710 // context and into the identifier resolver chain for name lookup 3711 // purposes. 3712 SmallVector<NamedDecl*, 2> Chain; 3713 Chain.push_back(Anon); 3714 3715 RecordDecl *RecordDef = Record->getDefinition(); 3716 if (!RecordDef || InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 3717 RecordDef, AS_none, 3718 Chain, true)) 3719 Anon->setInvalidDecl(); 3720 3721 return Anon; 3722 } 3723 3724 /// GetNameForDeclarator - Determine the full declaration name for the 3725 /// given Declarator. 3726 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 3727 return GetNameFromUnqualifiedId(D.getName()); 3728 } 3729 3730 /// \brief Retrieves the declaration name from a parsed unqualified-id. 3731 DeclarationNameInfo 3732 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 3733 DeclarationNameInfo NameInfo; 3734 NameInfo.setLoc(Name.StartLocation); 3735 3736 switch (Name.getKind()) { 3737 3738 case UnqualifiedId::IK_ImplicitSelfParam: 3739 case UnqualifiedId::IK_Identifier: 3740 NameInfo.setName(Name.Identifier); 3741 NameInfo.setLoc(Name.StartLocation); 3742 return NameInfo; 3743 3744 case UnqualifiedId::IK_OperatorFunctionId: 3745 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 3746 Name.OperatorFunctionId.Operator)); 3747 NameInfo.setLoc(Name.StartLocation); 3748 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 3749 = Name.OperatorFunctionId.SymbolLocations[0]; 3750 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 3751 = Name.EndLocation.getRawEncoding(); 3752 return NameInfo; 3753 3754 case UnqualifiedId::IK_LiteralOperatorId: 3755 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 3756 Name.Identifier)); 3757 NameInfo.setLoc(Name.StartLocation); 3758 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 3759 return NameInfo; 3760 3761 case UnqualifiedId::IK_ConversionFunctionId: { 3762 TypeSourceInfo *TInfo; 3763 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 3764 if (Ty.isNull()) 3765 return DeclarationNameInfo(); 3766 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 3767 Context.getCanonicalType(Ty))); 3768 NameInfo.setLoc(Name.StartLocation); 3769 NameInfo.setNamedTypeInfo(TInfo); 3770 return NameInfo; 3771 } 3772 3773 case UnqualifiedId::IK_ConstructorName: { 3774 TypeSourceInfo *TInfo; 3775 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 3776 if (Ty.isNull()) 3777 return DeclarationNameInfo(); 3778 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 3779 Context.getCanonicalType(Ty))); 3780 NameInfo.setLoc(Name.StartLocation); 3781 NameInfo.setNamedTypeInfo(TInfo); 3782 return NameInfo; 3783 } 3784 3785 case UnqualifiedId::IK_ConstructorTemplateId: { 3786 // In well-formed code, we can only have a constructor 3787 // template-id that refers to the current context, so go there 3788 // to find the actual type being constructed. 3789 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 3790 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 3791 return DeclarationNameInfo(); 3792 3793 // Determine the type of the class being constructed. 3794 QualType CurClassType = Context.getTypeDeclType(CurClass); 3795 3796 // FIXME: Check two things: that the template-id names the same type as 3797 // CurClassType, and that the template-id does not occur when the name 3798 // was qualified. 3799 3800 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 3801 Context.getCanonicalType(CurClassType))); 3802 NameInfo.setLoc(Name.StartLocation); 3803 // FIXME: should we retrieve TypeSourceInfo? 3804 NameInfo.setNamedTypeInfo(0); 3805 return NameInfo; 3806 } 3807 3808 case UnqualifiedId::IK_DestructorName: { 3809 TypeSourceInfo *TInfo; 3810 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 3811 if (Ty.isNull()) 3812 return DeclarationNameInfo(); 3813 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 3814 Context.getCanonicalType(Ty))); 3815 NameInfo.setLoc(Name.StartLocation); 3816 NameInfo.setNamedTypeInfo(TInfo); 3817 return NameInfo; 3818 } 3819 3820 case UnqualifiedId::IK_TemplateId: { 3821 TemplateName TName = Name.TemplateId->Template.get(); 3822 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 3823 return Context.getNameForTemplate(TName, TNameLoc); 3824 } 3825 3826 } // switch (Name.getKind()) 3827 3828 llvm_unreachable("Unknown name kind"); 3829 } 3830 3831 static QualType getCoreType(QualType Ty) { 3832 do { 3833 if (Ty->isPointerType() || Ty->isReferenceType()) 3834 Ty = Ty->getPointeeType(); 3835 else if (Ty->isArrayType()) 3836 Ty = Ty->castAsArrayTypeUnsafe()->getElementType(); 3837 else 3838 return Ty.withoutLocalFastQualifiers(); 3839 } while (true); 3840 } 3841 3842 /// hasSimilarParameters - Determine whether the C++ functions Declaration 3843 /// and Definition have "nearly" matching parameters. This heuristic is 3844 /// used to improve diagnostics in the case where an out-of-line function 3845 /// definition doesn't match any declaration within the class or namespace. 3846 /// Also sets Params to the list of indices to the parameters that differ 3847 /// between the declaration and the definition. If hasSimilarParameters 3848 /// returns true and Params is empty, then all of the parameters match. 3849 static bool hasSimilarParameters(ASTContext &Context, 3850 FunctionDecl *Declaration, 3851 FunctionDecl *Definition, 3852 SmallVectorImpl<unsigned> &Params) { 3853 Params.clear(); 3854 if (Declaration->param_size() != Definition->param_size()) 3855 return false; 3856 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 3857 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 3858 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 3859 3860 // The parameter types are identical 3861 if (Context.hasSameType(DefParamTy, DeclParamTy)) 3862 continue; 3863 3864 QualType DeclParamBaseTy = getCoreType(DeclParamTy); 3865 QualType DefParamBaseTy = getCoreType(DefParamTy); 3866 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier(); 3867 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier(); 3868 3869 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) || 3870 (DeclTyName && DeclTyName == DefTyName)) 3871 Params.push_back(Idx); 3872 else // The two parameters aren't even close 3873 return false; 3874 } 3875 3876 return true; 3877 } 3878 3879 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given 3880 /// declarator needs to be rebuilt in the current instantiation. 3881 /// Any bits of declarator which appear before the name are valid for 3882 /// consideration here. That's specifically the type in the decl spec 3883 /// and the base type in any member-pointer chunks. 3884 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 3885 DeclarationName Name) { 3886 // The types we specifically need to rebuild are: 3887 // - typenames, typeofs, and decltypes 3888 // - types which will become injected class names 3889 // Of course, we also need to rebuild any type referencing such a 3890 // type. It's safest to just say "dependent", but we call out a 3891 // few cases here. 3892 3893 DeclSpec &DS = D.getMutableDeclSpec(); 3894 switch (DS.getTypeSpecType()) { 3895 case DeclSpec::TST_typename: 3896 case DeclSpec::TST_typeofType: 3897 case DeclSpec::TST_underlyingType: 3898 case DeclSpec::TST_atomic: { 3899 // Grab the type from the parser. 3900 TypeSourceInfo *TSI = 0; 3901 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 3902 if (T.isNull() || !T->isDependentType()) break; 3903 3904 // Make sure there's a type source info. This isn't really much 3905 // of a waste; most dependent types should have type source info 3906 // attached already. 3907 if (!TSI) 3908 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 3909 3910 // Rebuild the type in the current instantiation. 3911 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 3912 if (!TSI) return true; 3913 3914 // Store the new type back in the decl spec. 3915 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 3916 DS.UpdateTypeRep(LocType); 3917 break; 3918 } 3919 3920 case DeclSpec::TST_decltype: 3921 case DeclSpec::TST_typeofExpr: { 3922 Expr *E = DS.getRepAsExpr(); 3923 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 3924 if (Result.isInvalid()) return true; 3925 DS.UpdateExprRep(Result.get()); 3926 break; 3927 } 3928 3929 default: 3930 // Nothing to do for these decl specs. 3931 break; 3932 } 3933 3934 // It doesn't matter what order we do this in. 3935 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 3936 DeclaratorChunk &Chunk = D.getTypeObject(I); 3937 3938 // The only type information in the declarator which can come 3939 // before the declaration name is the base type of a member 3940 // pointer. 3941 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 3942 continue; 3943 3944 // Rebuild the scope specifier in-place. 3945 CXXScopeSpec &SS = Chunk.Mem.Scope(); 3946 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 3947 return true; 3948 } 3949 3950 return false; 3951 } 3952 3953 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 3954 D.setFunctionDefinitionKind(FDK_Declaration); 3955 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg()); 3956 3957 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() && 3958 Dcl && Dcl->getDeclContext()->isFileContext()) 3959 Dcl->setTopLevelDeclInObjCContainer(); 3960 3961 return Dcl; 3962 } 3963 3964 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13: 3965 /// If T is the name of a class, then each of the following shall have a 3966 /// name different from T: 3967 /// - every static data member of class T; 3968 /// - every member function of class T 3969 /// - every member of class T that is itself a type; 3970 /// \returns true if the declaration name violates these rules. 3971 bool Sema::DiagnoseClassNameShadow(DeclContext *DC, 3972 DeclarationNameInfo NameInfo) { 3973 DeclarationName Name = NameInfo.getName(); 3974 3975 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 3976 if (Record->getIdentifier() && Record->getDeclName() == Name) { 3977 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name; 3978 return true; 3979 } 3980 3981 return false; 3982 } 3983 3984 /// \brief Diagnose a declaration whose declarator-id has the given 3985 /// nested-name-specifier. 3986 /// 3987 /// \param SS The nested-name-specifier of the declarator-id. 3988 /// 3989 /// \param DC The declaration context to which the nested-name-specifier 3990 /// resolves. 3991 /// 3992 /// \param Name The name of the entity being declared. 3993 /// 3994 /// \param Loc The location of the name of the entity being declared. 3995 /// 3996 /// \returns true if we cannot safely recover from this error, false otherwise. 3997 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC, 3998 DeclarationName Name, 3999 SourceLocation Loc) { 4000 DeclContext *Cur = CurContext; 4001 while (isa<LinkageSpecDecl>(Cur)) 4002 Cur = Cur->getParent(); 4003 4004 // C++ [dcl.meaning]p1: 4005 // A declarator-id shall not be qualified except for the definition 4006 // of a member function (9.3) or static data member (9.4) outside of 4007 // its class, the definition or explicit instantiation of a function 4008 // or variable member of a namespace outside of its namespace, or the 4009 // definition of an explicit specialization outside of its namespace, 4010 // or the declaration of a friend function that is a member of 4011 // another class or namespace (11.3). [...] 4012 4013 // The user provided a superfluous scope specifier that refers back to the 4014 // class or namespaces in which the entity is already declared. 4015 // 4016 // class X { 4017 // void X::f(); 4018 // }; 4019 if (Cur->Equals(DC)) { 4020 Diag(Loc, LangOpts.MicrosoftExt? diag::warn_member_extra_qualification 4021 : diag::err_member_extra_qualification) 4022 << Name << FixItHint::CreateRemoval(SS.getRange()); 4023 SS.clear(); 4024 return false; 4025 } 4026 4027 // Check whether the qualifying scope encloses the scope of the original 4028 // declaration. 4029 if (!Cur->Encloses(DC)) { 4030 if (Cur->isRecord()) 4031 Diag(Loc, diag::err_member_qualification) 4032 << Name << SS.getRange(); 4033 else if (isa<TranslationUnitDecl>(DC)) 4034 Diag(Loc, diag::err_invalid_declarator_global_scope) 4035 << Name << SS.getRange(); 4036 else if (isa<FunctionDecl>(Cur)) 4037 Diag(Loc, diag::err_invalid_declarator_in_function) 4038 << Name << SS.getRange(); 4039 else 4040 Diag(Loc, diag::err_invalid_declarator_scope) 4041 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange(); 4042 4043 return true; 4044 } 4045 4046 if (Cur->isRecord()) { 4047 // Cannot qualify members within a class. 4048 Diag(Loc, diag::err_member_qualification) 4049 << Name << SS.getRange(); 4050 SS.clear(); 4051 4052 // C++ constructors and destructors with incorrect scopes can break 4053 // our AST invariants by having the wrong underlying types. If 4054 // that's the case, then drop this declaration entirely. 4055 if ((Name.getNameKind() == DeclarationName::CXXConstructorName || 4056 Name.getNameKind() == DeclarationName::CXXDestructorName) && 4057 !Context.hasSameType(Name.getCXXNameType(), 4058 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur)))) 4059 return true; 4060 4061 return false; 4062 } 4063 4064 // C++11 [dcl.meaning]p1: 4065 // [...] "The nested-name-specifier of the qualified declarator-id shall 4066 // not begin with a decltype-specifer" 4067 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data()); 4068 while (SpecLoc.getPrefix()) 4069 SpecLoc = SpecLoc.getPrefix(); 4070 if (dyn_cast_or_null<DecltypeType>( 4071 SpecLoc.getNestedNameSpecifier()->getAsType())) 4072 Diag(Loc, diag::err_decltype_in_declarator) 4073 << SpecLoc.getTypeLoc().getSourceRange(); 4074 4075 return false; 4076 } 4077 4078 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D, 4079 MultiTemplateParamsArg TemplateParamLists) { 4080 // TODO: consider using NameInfo for diagnostic. 4081 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 4082 DeclarationName Name = NameInfo.getName(); 4083 4084 // All of these full declarators require an identifier. If it doesn't have 4085 // one, the ParsedFreeStandingDeclSpec action should be used. 4086 if (!Name) { 4087 if (!D.isInvalidType()) // Reject this if we think it is valid. 4088 Diag(D.getDeclSpec().getLocStart(), 4089 diag::err_declarator_need_ident) 4090 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 4091 return 0; 4092 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 4093 return 0; 4094 4095 // The scope passed in may not be a decl scope. Zip up the scope tree until 4096 // we find one that is. 4097 while ((S->getFlags() & Scope::DeclScope) == 0 || 4098 (S->getFlags() & Scope::TemplateParamScope) != 0) 4099 S = S->getParent(); 4100 4101 DeclContext *DC = CurContext; 4102 if (D.getCXXScopeSpec().isInvalid()) 4103 D.setInvalidType(); 4104 else if (D.getCXXScopeSpec().isSet()) { 4105 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 4106 UPPC_DeclarationQualifier)) 4107 return 0; 4108 4109 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 4110 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 4111 if (!DC) { 4112 // If we could not compute the declaration context, it's because the 4113 // declaration context is dependent but does not refer to a class, 4114 // class template, or class template partial specialization. Complain 4115 // and return early, to avoid the coming semantic disaster. 4116 Diag(D.getIdentifierLoc(), 4117 diag::err_template_qualified_declarator_no_match) 4118 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 4119 << D.getCXXScopeSpec().getRange(); 4120 return 0; 4121 } 4122 bool IsDependentContext = DC->isDependentContext(); 4123 4124 if (!IsDependentContext && 4125 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 4126 return 0; 4127 4128 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 4129 Diag(D.getIdentifierLoc(), 4130 diag::err_member_def_undefined_record) 4131 << Name << DC << D.getCXXScopeSpec().getRange(); 4132 D.setInvalidType(); 4133 } else if (!D.getDeclSpec().isFriendSpecified()) { 4134 if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC, 4135 Name, D.getIdentifierLoc())) { 4136 if (DC->isRecord()) 4137 return 0; 4138 4139 D.setInvalidType(); 4140 } 4141 } 4142 4143 // Check whether we need to rebuild the type of the given 4144 // declaration in the current instantiation. 4145 if (EnteringContext && IsDependentContext && 4146 TemplateParamLists.size() != 0) { 4147 ContextRAII SavedContext(*this, DC); 4148 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 4149 D.setInvalidType(); 4150 } 4151 } 4152 4153 if (DiagnoseClassNameShadow(DC, NameInfo)) 4154 // If this is a typedef, we'll end up spewing multiple diagnostics. 4155 // Just return early; it's safer. 4156 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 4157 return 0; 4158 4159 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 4160 QualType R = TInfo->getType(); 4161 4162 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 4163 UPPC_DeclarationType)) 4164 D.setInvalidType(); 4165 4166 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 4167 ForRedeclaration); 4168 4169 // See if this is a redefinition of a variable in the same scope. 4170 if (!D.getCXXScopeSpec().isSet()) { 4171 bool IsLinkageLookup = false; 4172 4173 // If the declaration we're planning to build will be a function 4174 // or object with linkage, then look for another declaration with 4175 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 4176 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 4177 /* Do nothing*/; 4178 else if (R->isFunctionType()) { 4179 if (CurContext->isFunctionOrMethod() || 4180 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 4181 IsLinkageLookup = true; 4182 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 4183 IsLinkageLookup = true; 4184 else if (CurContext->getRedeclContext()->isTranslationUnit() && 4185 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 4186 IsLinkageLookup = true; 4187 4188 if (IsLinkageLookup) 4189 Previous.clear(LookupRedeclarationWithLinkage); 4190 4191 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 4192 } else { // Something like "int foo::x;" 4193 LookupQualifiedName(Previous, DC); 4194 4195 // C++ [dcl.meaning]p1: 4196 // When the declarator-id is qualified, the declaration shall refer to a 4197 // previously declared member of the class or namespace to which the 4198 // qualifier refers (or, in the case of a namespace, of an element of the 4199 // inline namespace set of that namespace (7.3.1)) or to a specialization 4200 // thereof; [...] 4201 // 4202 // Note that we already checked the context above, and that we do not have 4203 // enough information to make sure that Previous contains the declaration 4204 // we want to match. For example, given: 4205 // 4206 // class X { 4207 // void f(); 4208 // void f(float); 4209 // }; 4210 // 4211 // void X::f(int) { } // ill-formed 4212 // 4213 // In this case, Previous will point to the overload set 4214 // containing the two f's declared in X, but neither of them 4215 // matches. 4216 4217 // C++ [dcl.meaning]p1: 4218 // [...] the member shall not merely have been introduced by a 4219 // using-declaration in the scope of the class or namespace nominated by 4220 // the nested-name-specifier of the declarator-id. 4221 RemoveUsingDecls(Previous); 4222 } 4223 4224 if (Previous.isSingleResult() && 4225 Previous.getFoundDecl()->isTemplateParameter()) { 4226 // Maybe we will complain about the shadowed template parameter. 4227 if (!D.isInvalidType()) 4228 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 4229 Previous.getFoundDecl()); 4230 4231 // Just pretend that we didn't see the previous declaration. 4232 Previous.clear(); 4233 } 4234 4235 // In C++, the previous declaration we find might be a tag type 4236 // (class or enum). In this case, the new declaration will hide the 4237 // tag type. Note that this does does not apply if we're declaring a 4238 // typedef (C++ [dcl.typedef]p4). 4239 if (Previous.isSingleTagDecl() && 4240 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 4241 Previous.clear(); 4242 4243 // Check that there are no default arguments other than in the parameters 4244 // of a function declaration (C++ only). 4245 if (getLangOpts().CPlusPlus) 4246 CheckExtraCXXDefaultArguments(D); 4247 4248 NamedDecl *New; 4249 4250 bool AddToScope = true; 4251 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 4252 if (TemplateParamLists.size()) { 4253 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 4254 return 0; 4255 } 4256 4257 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous); 4258 } else if (R->isFunctionType()) { 4259 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous, 4260 TemplateParamLists, 4261 AddToScope); 4262 } else { 4263 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists, 4264 AddToScope); 4265 } 4266 4267 if (New == 0) 4268 return 0; 4269 4270 // If this has an identifier and is not an invalid redeclaration or 4271 // function template specialization, add it to the scope stack. 4272 if (New->getDeclName() && AddToScope && 4273 !(D.isRedeclaration() && New->isInvalidDecl())) 4274 PushOnScopeChains(New, S); 4275 4276 return New; 4277 } 4278 4279 /// Helper method to turn variable array types into constant array 4280 /// types in certain situations which would otherwise be errors (for 4281 /// GCC compatibility). 4282 static QualType TryToFixInvalidVariablyModifiedType(QualType T, 4283 ASTContext &Context, 4284 bool &SizeIsNegative, 4285 llvm::APSInt &Oversized) { 4286 // This method tries to turn a variable array into a constant 4287 // array even when the size isn't an ICE. This is necessary 4288 // for compatibility with code that depends on gcc's buggy 4289 // constant expression folding, like struct {char x[(int)(char*)2];} 4290 SizeIsNegative = false; 4291 Oversized = 0; 4292 4293 if (T->isDependentType()) 4294 return QualType(); 4295 4296 QualifierCollector Qs; 4297 const Type *Ty = Qs.strip(T); 4298 4299 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 4300 QualType Pointee = PTy->getPointeeType(); 4301 QualType FixedType = 4302 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 4303 Oversized); 4304 if (FixedType.isNull()) return FixedType; 4305 FixedType = Context.getPointerType(FixedType); 4306 return Qs.apply(Context, FixedType); 4307 } 4308 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 4309 QualType Inner = PTy->getInnerType(); 4310 QualType FixedType = 4311 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 4312 Oversized); 4313 if (FixedType.isNull()) return FixedType; 4314 FixedType = Context.getParenType(FixedType); 4315 return Qs.apply(Context, FixedType); 4316 } 4317 4318 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 4319 if (!VLATy) 4320 return QualType(); 4321 // FIXME: We should probably handle this case 4322 if (VLATy->getElementType()->isVariablyModifiedType()) 4323 return QualType(); 4324 4325 llvm::APSInt Res; 4326 if (!VLATy->getSizeExpr() || 4327 !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context)) 4328 return QualType(); 4329 4330 // Check whether the array size is negative. 4331 if (Res.isSigned() && Res.isNegative()) { 4332 SizeIsNegative = true; 4333 return QualType(); 4334 } 4335 4336 // Check whether the array is too large to be addressed. 4337 unsigned ActiveSizeBits 4338 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 4339 Res); 4340 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 4341 Oversized = Res; 4342 return QualType(); 4343 } 4344 4345 return Context.getConstantArrayType(VLATy->getElementType(), 4346 Res, ArrayType::Normal, 0); 4347 } 4348 4349 static void 4350 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) { 4351 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) { 4352 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>(); 4353 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(), 4354 DstPTL.getPointeeLoc()); 4355 DstPTL.setStarLoc(SrcPTL.getStarLoc()); 4356 return; 4357 } 4358 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) { 4359 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>(); 4360 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(), 4361 DstPTL.getInnerLoc()); 4362 DstPTL.setLParenLoc(SrcPTL.getLParenLoc()); 4363 DstPTL.setRParenLoc(SrcPTL.getRParenLoc()); 4364 return; 4365 } 4366 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>(); 4367 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>(); 4368 TypeLoc SrcElemTL = SrcATL.getElementLoc(); 4369 TypeLoc DstElemTL = DstATL.getElementLoc(); 4370 DstElemTL.initializeFullCopy(SrcElemTL); 4371 DstATL.setLBracketLoc(SrcATL.getLBracketLoc()); 4372 DstATL.setSizeExpr(SrcATL.getSizeExpr()); 4373 DstATL.setRBracketLoc(SrcATL.getRBracketLoc()); 4374 } 4375 4376 /// Helper method to turn variable array types into constant array 4377 /// types in certain situations which would otherwise be errors (for 4378 /// GCC compatibility). 4379 static TypeSourceInfo* 4380 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo, 4381 ASTContext &Context, 4382 bool &SizeIsNegative, 4383 llvm::APSInt &Oversized) { 4384 QualType FixedTy 4385 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context, 4386 SizeIsNegative, Oversized); 4387 if (FixedTy.isNull()) 4388 return 0; 4389 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy); 4390 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(), 4391 FixedTInfo->getTypeLoc()); 4392 return FixedTInfo; 4393 } 4394 4395 /// \brief Register the given locally-scoped extern "C" declaration so 4396 /// that it can be found later for redeclarations. We include any extern "C" 4397 /// declaration that is not visible in the translation unit here, not just 4398 /// function-scope declarations. 4399 void 4400 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) { 4401 if (!getLangOpts().CPlusPlus && 4402 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit()) 4403 // Don't need to track declarations in the TU in C. 4404 return; 4405 4406 // Note that we have a locally-scoped external with this name. 4407 // FIXME: There can be multiple such declarations if they are functions marked 4408 // __attribute__((overloadable)) declared in function scope in C. 4409 LocallyScopedExternCDecls[ND->getDeclName()] = ND; 4410 } 4411 4412 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) { 4413 if (ExternalSource) { 4414 // Load locally-scoped external decls from the external source. 4415 // FIXME: This is inefficient. Maybe add a DeclContext for extern "C" decls? 4416 SmallVector<NamedDecl *, 4> Decls; 4417 ExternalSource->ReadLocallyScopedExternCDecls(Decls); 4418 for (unsigned I = 0, N = Decls.size(); I != N; ++I) { 4419 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4420 = LocallyScopedExternCDecls.find(Decls[I]->getDeclName()); 4421 if (Pos == LocallyScopedExternCDecls.end()) 4422 LocallyScopedExternCDecls[Decls[I]->getDeclName()] = Decls[I]; 4423 } 4424 } 4425 4426 NamedDecl *D = LocallyScopedExternCDecls.lookup(Name); 4427 return D ? cast<NamedDecl>(D->getMostRecentDecl()) : 0; 4428 } 4429 4430 /// \brief Diagnose function specifiers on a declaration of an identifier that 4431 /// does not identify a function. 4432 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) { 4433 // FIXME: We should probably indicate the identifier in question to avoid 4434 // confusion for constructs like "inline int a(), b;" 4435 if (DS.isInlineSpecified()) 4436 Diag(DS.getInlineSpecLoc(), 4437 diag::err_inline_non_function); 4438 4439 if (DS.isVirtualSpecified()) 4440 Diag(DS.getVirtualSpecLoc(), 4441 diag::err_virtual_non_function); 4442 4443 if (DS.isExplicitSpecified()) 4444 Diag(DS.getExplicitSpecLoc(), 4445 diag::err_explicit_non_function); 4446 4447 if (DS.isNoreturnSpecified()) 4448 Diag(DS.getNoreturnSpecLoc(), 4449 diag::err_noreturn_non_function); 4450 } 4451 4452 NamedDecl* 4453 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 4454 TypeSourceInfo *TInfo, LookupResult &Previous) { 4455 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 4456 if (D.getCXXScopeSpec().isSet()) { 4457 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 4458 << D.getCXXScopeSpec().getRange(); 4459 D.setInvalidType(); 4460 // Pretend we didn't see the scope specifier. 4461 DC = CurContext; 4462 Previous.clear(); 4463 } 4464 4465 DiagnoseFunctionSpecifiers(D.getDeclSpec()); 4466 4467 if (D.getDeclSpec().isConstexprSpecified()) 4468 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr) 4469 << 1; 4470 4471 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 4472 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 4473 << D.getName().getSourceRange(); 4474 return 0; 4475 } 4476 4477 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo); 4478 if (!NewTD) return 0; 4479 4480 // Handle attributes prior to checking for duplicates in MergeVarDecl 4481 ProcessDeclAttributes(S, NewTD, D); 4482 4483 CheckTypedefForVariablyModifiedType(S, NewTD); 4484 4485 bool Redeclaration = D.isRedeclaration(); 4486 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration); 4487 D.setRedeclaration(Redeclaration); 4488 return ND; 4489 } 4490 4491 void 4492 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) { 4493 // C99 6.7.7p2: If a typedef name specifies a variably modified type 4494 // then it shall have block scope. 4495 // Note that variably modified types must be fixed before merging the decl so 4496 // that redeclarations will match. 4497 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo(); 4498 QualType T = TInfo->getType(); 4499 if (T->isVariablyModifiedType()) { 4500 getCurFunction()->setHasBranchProtectedScope(); 4501 4502 if (S->getFnParent() == 0) { 4503 bool SizeIsNegative; 4504 llvm::APSInt Oversized; 4505 TypeSourceInfo *FixedTInfo = 4506 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context, 4507 SizeIsNegative, 4508 Oversized); 4509 if (FixedTInfo) { 4510 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size); 4511 NewTD->setTypeSourceInfo(FixedTInfo); 4512 } else { 4513 if (SizeIsNegative) 4514 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size); 4515 else if (T->isVariableArrayType()) 4516 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope); 4517 else if (Oversized.getBoolValue()) 4518 Diag(NewTD->getLocation(), diag::err_array_too_large) 4519 << Oversized.toString(10); 4520 else 4521 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope); 4522 NewTD->setInvalidDecl(); 4523 } 4524 } 4525 } 4526 } 4527 4528 4529 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which 4530 /// declares a typedef-name, either using the 'typedef' type specifier or via 4531 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'. 4532 NamedDecl* 4533 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD, 4534 LookupResult &Previous, bool &Redeclaration) { 4535 // Merge the decl with the existing one if appropriate. If the decl is 4536 // in an outer scope, it isn't the same thing. 4537 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/ false, 4538 /*ExplicitInstantiationOrSpecialization=*/false); 4539 filterNonConflictingPreviousDecls(Context, NewTD, Previous); 4540 if (!Previous.empty()) { 4541 Redeclaration = true; 4542 MergeTypedefNameDecl(NewTD, Previous); 4543 } 4544 4545 // If this is the C FILE type, notify the AST context. 4546 if (IdentifierInfo *II = NewTD->getIdentifier()) 4547 if (!NewTD->isInvalidDecl() && 4548 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4549 if (II->isStr("FILE")) 4550 Context.setFILEDecl(NewTD); 4551 else if (II->isStr("jmp_buf")) 4552 Context.setjmp_bufDecl(NewTD); 4553 else if (II->isStr("sigjmp_buf")) 4554 Context.setsigjmp_bufDecl(NewTD); 4555 else if (II->isStr("ucontext_t")) 4556 Context.setucontext_tDecl(NewTD); 4557 } 4558 4559 return NewTD; 4560 } 4561 4562 /// \brief Determines whether the given declaration is an out-of-scope 4563 /// previous declaration. 4564 /// 4565 /// This routine should be invoked when name lookup has found a 4566 /// previous declaration (PrevDecl) that is not in the scope where a 4567 /// new declaration by the same name is being introduced. If the new 4568 /// declaration occurs in a local scope, previous declarations with 4569 /// linkage may still be considered previous declarations (C99 4570 /// 6.2.2p4-5, C++ [basic.link]p6). 4571 /// 4572 /// \param PrevDecl the previous declaration found by name 4573 /// lookup 4574 /// 4575 /// \param DC the context in which the new declaration is being 4576 /// declared. 4577 /// 4578 /// \returns true if PrevDecl is an out-of-scope previous declaration 4579 /// for a new delcaration with the same name. 4580 static bool 4581 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 4582 ASTContext &Context) { 4583 if (!PrevDecl) 4584 return false; 4585 4586 if (!PrevDecl->hasLinkage()) 4587 return false; 4588 4589 if (Context.getLangOpts().CPlusPlus) { 4590 // C++ [basic.link]p6: 4591 // If there is a visible declaration of an entity with linkage 4592 // having the same name and type, ignoring entities declared 4593 // outside the innermost enclosing namespace scope, the block 4594 // scope declaration declares that same entity and receives the 4595 // linkage of the previous declaration. 4596 DeclContext *OuterContext = DC->getRedeclContext(); 4597 if (!OuterContext->isFunctionOrMethod()) 4598 // This rule only applies to block-scope declarations. 4599 return false; 4600 4601 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 4602 if (PrevOuterContext->isRecord()) 4603 // We found a member function: ignore it. 4604 return false; 4605 4606 // Find the innermost enclosing namespace for the new and 4607 // previous declarations. 4608 OuterContext = OuterContext->getEnclosingNamespaceContext(); 4609 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 4610 4611 // The previous declaration is in a different namespace, so it 4612 // isn't the same function. 4613 if (!OuterContext->Equals(PrevOuterContext)) 4614 return false; 4615 } 4616 4617 return true; 4618 } 4619 4620 static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 4621 CXXScopeSpec &SS = D.getCXXScopeSpec(); 4622 if (!SS.isSet()) return; 4623 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 4624 } 4625 4626 bool Sema::inferObjCARCLifetime(ValueDecl *decl) { 4627 QualType type = decl->getType(); 4628 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime(); 4629 if (lifetime == Qualifiers::OCL_Autoreleasing) { 4630 // Various kinds of declaration aren't allowed to be __autoreleasing. 4631 unsigned kind = -1U; 4632 if (VarDecl *var = dyn_cast<VarDecl>(decl)) { 4633 if (var->hasAttr<BlocksAttr>()) 4634 kind = 0; // __block 4635 else if (!var->hasLocalStorage()) 4636 kind = 1; // global 4637 } else if (isa<ObjCIvarDecl>(decl)) { 4638 kind = 3; // ivar 4639 } else if (isa<FieldDecl>(decl)) { 4640 kind = 2; // field 4641 } 4642 4643 if (kind != -1U) { 4644 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var) 4645 << kind; 4646 } 4647 } else if (lifetime == Qualifiers::OCL_None) { 4648 // Try to infer lifetime. 4649 if (!type->isObjCLifetimeType()) 4650 return false; 4651 4652 lifetime = type->getObjCARCImplicitLifetime(); 4653 type = Context.getLifetimeQualifiedType(type, lifetime); 4654 decl->setType(type); 4655 } 4656 4657 if (VarDecl *var = dyn_cast<VarDecl>(decl)) { 4658 // Thread-local variables cannot have lifetime. 4659 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone && 4660 var->getTLSKind()) { 4661 Diag(var->getLocation(), diag::err_arc_thread_ownership) 4662 << var->getType(); 4663 return true; 4664 } 4665 } 4666 4667 return false; 4668 } 4669 4670 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) { 4671 // 'weak' only applies to declarations with external linkage. 4672 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) { 4673 if (!ND.isExternallyVisible()) { 4674 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static); 4675 ND.dropAttr<WeakAttr>(); 4676 } 4677 } 4678 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) { 4679 if (ND.isExternallyVisible()) { 4680 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static); 4681 ND.dropAttr<WeakRefAttr>(); 4682 } 4683 } 4684 4685 // 'selectany' only applies to externally visible varable declarations. 4686 // It does not apply to functions. 4687 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) { 4688 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) { 4689 S.Diag(Attr->getLocation(), diag::err_attribute_selectany_non_extern_data); 4690 ND.dropAttr<SelectAnyAttr>(); 4691 } 4692 } 4693 } 4694 4695 /// Given that we are within the definition of the given function, 4696 /// will that definition behave like C99's 'inline', where the 4697 /// definition is discarded except for optimization purposes? 4698 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) { 4699 // Try to avoid calling GetGVALinkageForFunction. 4700 4701 // All cases of this require the 'inline' keyword. 4702 if (!FD->isInlined()) return false; 4703 4704 // This is only possible in C++ with the gnu_inline attribute. 4705 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>()) 4706 return false; 4707 4708 // Okay, go ahead and call the relatively-more-expensive function. 4709 4710 #ifndef NDEBUG 4711 // AST quite reasonably asserts that it's working on a function 4712 // definition. We don't really have a way to tell it that we're 4713 // currently defining the function, so just lie to it in +Asserts 4714 // builds. This is an awful hack. 4715 FD->setLazyBody(1); 4716 #endif 4717 4718 bool isC99Inline = (S.Context.GetGVALinkageForFunction(FD) == GVA_C99Inline); 4719 4720 #ifndef NDEBUG 4721 FD->setLazyBody(0); 4722 #endif 4723 4724 return isC99Inline; 4725 } 4726 4727 /// Determine whether a variable is extern "C" prior to attaching 4728 /// an initializer. We can't just call isExternC() here, because that 4729 /// will also compute and cache whether the declaration is externally 4730 /// visible, which might change when we attach the initializer. 4731 /// 4732 /// This can only be used if the declaration is known to not be a 4733 /// redeclaration of an internal linkage declaration. 4734 /// 4735 /// For instance: 4736 /// 4737 /// auto x = []{}; 4738 /// 4739 /// Attaching the initializer here makes this declaration not externally 4740 /// visible, because its type has internal linkage. 4741 /// 4742 /// FIXME: This is a hack. 4743 template<typename T> 4744 static bool isIncompleteDeclExternC(Sema &S, const T *D) { 4745 if (S.getLangOpts().CPlusPlus) { 4746 // In C++, the overloadable attribute negates the effects of extern "C". 4747 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>()) 4748 return false; 4749 } 4750 return D->isExternC(); 4751 } 4752 4753 static bool shouldConsiderLinkage(const VarDecl *VD) { 4754 const DeclContext *DC = VD->getDeclContext()->getRedeclContext(); 4755 if (DC->isFunctionOrMethod()) 4756 return VD->hasExternalStorage(); 4757 if (DC->isFileContext()) 4758 return true; 4759 if (DC->isRecord()) 4760 return false; 4761 llvm_unreachable("Unexpected context"); 4762 } 4763 4764 static bool shouldConsiderLinkage(const FunctionDecl *FD) { 4765 const DeclContext *DC = FD->getDeclContext()->getRedeclContext(); 4766 if (DC->isFileContext() || DC->isFunctionOrMethod()) 4767 return true; 4768 if (DC->isRecord()) 4769 return false; 4770 llvm_unreachable("Unexpected context"); 4771 } 4772 4773 bool Sema::HandleVariableRedeclaration(Decl *D, CXXScopeSpec &SS) { 4774 // If this is a redeclaration of a variable template or a forward 4775 // declaration of a variable template partial specialization 4776 // with nested name specifier, complain. 4777 4778 if (D && SS.isNotEmpty() && 4779 (isa<VarTemplateDecl>(D) || 4780 isa<VarTemplatePartialSpecializationDecl>(D))) { 4781 Diag(SS.getBeginLoc(), diag::err_forward_var_nested_name_specifier) 4782 << isa<VarTemplatePartialSpecializationDecl>(D) << SS.getRange(); 4783 return true; 4784 } 4785 return false; 4786 } 4787 4788 NamedDecl * 4789 Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 4790 TypeSourceInfo *TInfo, LookupResult &Previous, 4791 MultiTemplateParamsArg TemplateParamLists, 4792 bool &AddToScope) { 4793 QualType R = TInfo->getType(); 4794 DeclarationName Name = GetNameForDeclarator(D).getName(); 4795 4796 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 4797 VarDecl::StorageClass SC = 4798 StorageClassSpecToVarDeclStorageClass(D.getDeclSpec()); 4799 4800 if (getLangOpts().OpenCL && !getOpenCLOptions().cl_khr_fp16) { 4801 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and 4802 // half array type (unless the cl_khr_fp16 extension is enabled). 4803 if (Context.getBaseElementType(R)->isHalfType()) { 4804 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R; 4805 D.setInvalidType(); 4806 } 4807 } 4808 4809 if (SCSpec == DeclSpec::SCS_mutable) { 4810 // mutable can only appear on non-static class members, so it's always 4811 // an error here 4812 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 4813 D.setInvalidType(); 4814 SC = SC_None; 4815 } 4816 4817 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register && 4818 !D.getAsmLabel() && !getSourceManager().isInSystemMacro( 4819 D.getDeclSpec().getStorageClassSpecLoc())) { 4820 // In C++11, the 'register' storage class specifier is deprecated. 4821 // Suppress the warning in system macros, it's used in macros in some 4822 // popular C system headers, such as in glibc's htonl() macro. 4823 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4824 diag::warn_deprecated_register) 4825 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4826 } 4827 4828 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4829 if (!II) { 4830 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 4831 << Name; 4832 return 0; 4833 } 4834 4835 DiagnoseFunctionSpecifiers(D.getDeclSpec()); 4836 4837 if (!DC->isRecord() && S->getFnParent() == 0) { 4838 // C99 6.9p2: The storage-class specifiers auto and register shall not 4839 // appear in the declaration specifiers in an external declaration. 4840 if (SC == SC_Auto || SC == SC_Register) { 4841 // If this is a register variable with an asm label specified, then this 4842 // is a GNU extension. 4843 if (SC == SC_Register && D.getAsmLabel()) 4844 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 4845 else 4846 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 4847 D.setInvalidType(); 4848 } 4849 } 4850 4851 if (getLangOpts().OpenCL) { 4852 // Set up the special work-group-local storage class for variables in the 4853 // OpenCL __local address space. 4854 if (R.getAddressSpace() == LangAS::opencl_local) { 4855 SC = SC_OpenCLWorkGroupLocal; 4856 } 4857 4858 // OpenCL v1.2 s6.9.b p4: 4859 // The sampler type cannot be used with the __local and __global address 4860 // space qualifiers. 4861 if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local || 4862 R.getAddressSpace() == LangAS::opencl_global)) { 4863 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace); 4864 } 4865 4866 // OpenCL 1.2 spec, p6.9 r: 4867 // The event type cannot be used to declare a program scope variable. 4868 // The event type cannot be used with the __local, __constant and __global 4869 // address space qualifiers. 4870 if (R->isEventT()) { 4871 if (S->getParent() == 0) { 4872 Diag(D.getLocStart(), diag::err_event_t_global_var); 4873 D.setInvalidType(); 4874 } 4875 4876 if (R.getAddressSpace()) { 4877 Diag(D.getLocStart(), diag::err_event_t_addr_space_qual); 4878 D.setInvalidType(); 4879 } 4880 } 4881 } 4882 4883 bool IsExplicitSpecialization = false; 4884 bool IsVariableTemplateSpecialization = false; 4885 bool IsPartialSpecialization = false; 4886 bool Invalid = false; // TODO: Can we remove this (error-prone)? 4887 TemplateParameterList *TemplateParams = 0; 4888 VarTemplateDecl *PrevVarTemplate = 0; 4889 VarDecl *NewVD; 4890 if (!getLangOpts().CPlusPlus) { 4891 NewVD = VarDecl::Create(Context, DC, D.getLocStart(), 4892 D.getIdentifierLoc(), II, 4893 R, TInfo, SC); 4894 4895 if (D.isInvalidType()) 4896 NewVD->setInvalidDecl(); 4897 } else { 4898 if (DC->isRecord() && !CurContext->isRecord()) { 4899 // This is an out-of-line definition of a static data member. 4900 switch (SC) { 4901 case SC_None: 4902 break; 4903 case SC_Static: 4904 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4905 diag::err_static_out_of_line) 4906 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4907 break; 4908 case SC_Auto: 4909 case SC_Register: 4910 case SC_Extern: 4911 // [dcl.stc] p2: The auto or register specifiers shall be applied only 4912 // to names of variables declared in a block or to function parameters. 4913 // [dcl.stc] p6: The extern specifier cannot be used in the declaration 4914 // of class members 4915 4916 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4917 diag::err_storage_class_for_static_member) 4918 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4919 break; 4920 case SC_PrivateExtern: 4921 llvm_unreachable("C storage class in c++!"); 4922 case SC_OpenCLWorkGroupLocal: 4923 llvm_unreachable("OpenCL storage class in c++!"); 4924 } 4925 } 4926 4927 if (SC == SC_Static && CurContext->isRecord()) { 4928 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 4929 if (RD->isLocalClass()) 4930 Diag(D.getIdentifierLoc(), 4931 diag::err_static_data_member_not_allowed_in_local_class) 4932 << Name << RD->getDeclName(); 4933 4934 // C++98 [class.union]p1: If a union contains a static data member, 4935 // the program is ill-formed. C++11 drops this restriction. 4936 if (RD->isUnion()) 4937 Diag(D.getIdentifierLoc(), 4938 getLangOpts().CPlusPlus11 4939 ? diag::warn_cxx98_compat_static_data_member_in_union 4940 : diag::ext_static_data_member_in_union) << Name; 4941 // We conservatively disallow static data members in anonymous structs. 4942 else if (!RD->getDeclName()) 4943 Diag(D.getIdentifierLoc(), 4944 diag::err_static_data_member_not_allowed_in_anon_struct) 4945 << Name << RD->isUnion(); 4946 } 4947 } 4948 4949 NamedDecl *PrevDecl = 0; 4950 if (Previous.begin() != Previous.end()) 4951 PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 4952 PrevVarTemplate = dyn_cast_or_null<VarTemplateDecl>(PrevDecl); 4953 4954 // Match up the template parameter lists with the scope specifier, then 4955 // determine whether we have a template or a template specialization. 4956 TemplateParams = MatchTemplateParametersToScopeSpecifier( 4957 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(), 4958 D.getCXXScopeSpec(), TemplateParamLists, 4959 /*never a friend*/ false, IsExplicitSpecialization, Invalid); 4960 if (TemplateParams) { 4961 if (!TemplateParams->size() && 4962 D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 4963 // There is an extraneous 'template<>' for this variable. Complain 4964 // about it, but allow the declaration of the variable. 4965 Diag(TemplateParams->getTemplateLoc(), 4966 diag::err_template_variable_noparams) 4967 << II 4968 << SourceRange(TemplateParams->getTemplateLoc(), 4969 TemplateParams->getRAngleLoc()); 4970 } else { 4971 // Only C++1y supports variable templates (N3651). 4972 Diag(D.getIdentifierLoc(), 4973 getLangOpts().CPlusPlus1y 4974 ? diag::warn_cxx11_compat_variable_template 4975 : diag::ext_variable_template); 4976 4977 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4978 // This is an explicit specialization or a partial specialization. 4979 // Check that we can declare a specialization here 4980 4981 IsVariableTemplateSpecialization = true; 4982 IsPartialSpecialization = TemplateParams->size() > 0; 4983 4984 } else { // if (TemplateParams->size() > 0) 4985 // This is a template declaration. 4986 4987 // Check that we can declare a template here. 4988 if (CheckTemplateDeclScope(S, TemplateParams)) 4989 return 0; 4990 4991 // If there is a previous declaration with the same name, check 4992 // whether this is a valid redeclaration. 4993 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S)) 4994 PrevDecl = PrevVarTemplate = 0; 4995 4996 if (PrevVarTemplate) { 4997 // Ensure that the template parameter lists are compatible. 4998 if (!TemplateParameterListsAreEqual( 4999 TemplateParams, PrevVarTemplate->getTemplateParameters(), 5000 /*Complain=*/true, TPL_TemplateMatch)) 5001 return 0; 5002 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 5003 // Maybe we will complain about the shadowed template parameter. 5004 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5005 5006 // Just pretend that we didn't see the previous declaration. 5007 PrevDecl = 0; 5008 } else if (PrevDecl) { 5009 // C++ [temp]p5: 5010 // ... a template name declared in namespace scope or in class 5011 // scope shall be unique in that scope. 5012 Diag(D.getIdentifierLoc(), diag::err_redefinition_different_kind) 5013 << Name; 5014 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5015 return 0; 5016 } 5017 5018 // Check the template parameter list of this declaration, possibly 5019 // merging in the template parameter list from the previous variable 5020 // template declaration. 5021 if (CheckTemplateParameterList( 5022 TemplateParams, 5023 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters() 5024 : 0, 5025 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() && 5026 DC->isDependentContext()) 5027 ? TPC_ClassTemplateMember 5028 : TPC_VarTemplate)) 5029 Invalid = true; 5030 5031 if (D.getCXXScopeSpec().isSet()) { 5032 // If the name of the template was qualified, we must be defining 5033 // the template out-of-line. 5034 if (!D.getCXXScopeSpec().isInvalid() && !Invalid && 5035 !PrevVarTemplate) { 5036 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 5037 << Name << DC << D.getCXXScopeSpec().getRange(); 5038 Invalid = true; 5039 } 5040 } 5041 } 5042 } 5043 } else if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 5044 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 5045 5046 // We have encountered something that the user meant to be a 5047 // specialization (because it has explicitly-specified template 5048 // arguments) but that was not introduced with a "template<>" (or had 5049 // too few of them). 5050 // FIXME: Differentiate between attempts for explicit instantiations 5051 // (starting with "template") and the rest. 5052 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 5053 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 5054 << FixItHint::CreateInsertion(D.getDeclSpec().getLocStart(), 5055 "template<> "); 5056 IsVariableTemplateSpecialization = true; 5057 } 5058 5059 if (IsVariableTemplateSpecialization) { 5060 if (!PrevVarTemplate) { 5061 Diag(D.getIdentifierLoc(), diag::err_var_spec_no_template) 5062 << IsPartialSpecialization; 5063 return 0; 5064 } 5065 5066 SourceLocation TemplateKWLoc = 5067 TemplateParamLists.size() > 0 5068 ? TemplateParamLists[0]->getTemplateLoc() 5069 : SourceLocation(); 5070 DeclResult Res = ActOnVarTemplateSpecialization( 5071 S, PrevVarTemplate, D, TInfo, TemplateKWLoc, TemplateParams, SC, 5072 IsPartialSpecialization); 5073 if (Res.isInvalid()) 5074 return 0; 5075 NewVD = cast<VarDecl>(Res.get()); 5076 AddToScope = false; 5077 } else 5078 NewVD = VarDecl::Create(Context, DC, D.getLocStart(), 5079 D.getIdentifierLoc(), II, R, TInfo, SC); 5080 5081 // If this decl has an auto type in need of deduction, make a note of the 5082 // Decl so we can diagnose uses of it in its own initializer. 5083 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType()) 5084 ParsingInitForAutoVars.insert(NewVD); 5085 5086 if (D.isInvalidType() || Invalid) 5087 NewVD->setInvalidDecl(); 5088 5089 SetNestedNameSpecifier(NewVD, D); 5090 5091 // FIXME: Do we need D.getCXXScopeSpec().isSet()? 5092 if (TemplateParams && TemplateParamLists.size() > 1 && 5093 (!IsVariableTemplateSpecialization || D.getCXXScopeSpec().isSet())) { 5094 NewVD->setTemplateParameterListsInfo( 5095 Context, TemplateParamLists.size() - 1, TemplateParamLists.data()); 5096 } else if (IsVariableTemplateSpecialization || 5097 (!TemplateParams && TemplateParamLists.size() > 0 && 5098 (D.getCXXScopeSpec().isSet()))) { 5099 NewVD->setTemplateParameterListsInfo(Context, 5100 TemplateParamLists.size(), 5101 TemplateParamLists.data()); 5102 } 5103 5104 if (D.getDeclSpec().isConstexprSpecified()) 5105 NewVD->setConstexpr(true); 5106 } 5107 5108 // Set the lexical context. If the declarator has a C++ scope specifier, the 5109 // lexical context will be different from the semantic context. 5110 NewVD->setLexicalDeclContext(CurContext); 5111 5112 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) { 5113 if (NewVD->hasLocalStorage()) { 5114 // C++11 [dcl.stc]p4: 5115 // When thread_local is applied to a variable of block scope the 5116 // storage-class-specifier static is implied if it does not appear 5117 // explicitly. 5118 // Core issue: 'static' is not implied if the variable is declared 5119 // 'extern'. 5120 if (SCSpec == DeclSpec::SCS_unspecified && 5121 TSCS == DeclSpec::TSCS_thread_local && 5122 DC->isFunctionOrMethod()) 5123 NewVD->setTSCSpec(TSCS); 5124 else 5125 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), 5126 diag::err_thread_non_global) 5127 << DeclSpec::getSpecifierName(TSCS); 5128 } else if (!Context.getTargetInfo().isTLSSupported()) 5129 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), 5130 diag::err_thread_unsupported); 5131 else 5132 NewVD->setTSCSpec(TSCS); 5133 } 5134 5135 // C99 6.7.4p3 5136 // An inline definition of a function with external linkage shall 5137 // not contain a definition of a modifiable object with static or 5138 // thread storage duration... 5139 // We only apply this when the function is required to be defined 5140 // elsewhere, i.e. when the function is not 'extern inline'. Note 5141 // that a local variable with thread storage duration still has to 5142 // be marked 'static'. Also note that it's possible to get these 5143 // semantics in C++ using __attribute__((gnu_inline)). 5144 if (SC == SC_Static && S->getFnParent() != 0 && 5145 !NewVD->getType().isConstQualified()) { 5146 FunctionDecl *CurFD = getCurFunctionDecl(); 5147 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) { 5148 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 5149 diag::warn_static_local_in_extern_inline); 5150 MaybeSuggestAddingStaticToDecl(CurFD); 5151 } 5152 } 5153 5154 if (D.getDeclSpec().isModulePrivateSpecified()) { 5155 if (IsVariableTemplateSpecialization) 5156 Diag(NewVD->getLocation(), diag::err_module_private_specialization) 5157 << (IsPartialSpecialization ? 1 : 0) 5158 << FixItHint::CreateRemoval( 5159 D.getDeclSpec().getModulePrivateSpecLoc()); 5160 else if (IsExplicitSpecialization) 5161 Diag(NewVD->getLocation(), diag::err_module_private_specialization) 5162 << 2 5163 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc()); 5164 else if (NewVD->hasLocalStorage()) 5165 Diag(NewVD->getLocation(), diag::err_module_private_local) 5166 << 0 << NewVD->getDeclName() 5167 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc()) 5168 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc()); 5169 else 5170 NewVD->setModulePrivate(); 5171 } 5172 5173 // Handle attributes prior to checking for duplicates in MergeVarDecl 5174 ProcessDeclAttributes(S, NewVD, D); 5175 5176 if (NewVD->hasAttrs()) 5177 CheckAlignasUnderalignment(NewVD); 5178 5179 if (getLangOpts().CUDA) { 5180 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static 5181 // storage [duration]." 5182 if (SC == SC_None && S->getFnParent() != 0 && 5183 (NewVD->hasAttr<CUDASharedAttr>() || 5184 NewVD->hasAttr<CUDAConstantAttr>())) { 5185 NewVD->setStorageClass(SC_Static); 5186 } 5187 } 5188 5189 // In auto-retain/release, infer strong retension for variables of 5190 // retainable type. 5191 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD)) 5192 NewVD->setInvalidDecl(); 5193 5194 // Handle GNU asm-label extension (encoded as an attribute). 5195 if (Expr *E = (Expr*)D.getAsmLabel()) { 5196 // The parser guarantees this is a string. 5197 StringLiteral *SE = cast<StringLiteral>(E); 5198 StringRef Label = SE->getString(); 5199 if (S->getFnParent() != 0) { 5200 switch (SC) { 5201 case SC_None: 5202 case SC_Auto: 5203 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 5204 break; 5205 case SC_Register: 5206 if (!Context.getTargetInfo().isValidGCCRegisterName(Label)) 5207 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 5208 break; 5209 case SC_Static: 5210 case SC_Extern: 5211 case SC_PrivateExtern: 5212 case SC_OpenCLWorkGroupLocal: 5213 break; 5214 } 5215 } 5216 5217 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 5218 Context, Label)); 5219 } else if (!ExtnameUndeclaredIdentifiers.empty()) { 5220 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I = 5221 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier()); 5222 if (I != ExtnameUndeclaredIdentifiers.end()) { 5223 NewVD->addAttr(I->second); 5224 ExtnameUndeclaredIdentifiers.erase(I); 5225 } 5226 } 5227 5228 // Diagnose shadowed variables before filtering for scope. 5229 // FIXME: Special treatment for static variable template members (?). 5230 if (!D.getCXXScopeSpec().isSet()) 5231 CheckShadow(S, NewVD, Previous); 5232 5233 // Don't consider existing declarations that are in a different 5234 // scope and are out-of-semantic-context declarations (if the new 5235 // declaration has linkage). 5236 FilterLookupForScope( 5237 Previous, DC, S, shouldConsiderLinkage(NewVD), 5238 IsExplicitSpecialization || IsVariableTemplateSpecialization); 5239 5240 if (!getLangOpts().CPlusPlus) { 5241 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous)); 5242 } else { 5243 // Merge the decl with the existing one if appropriate. 5244 if (!Previous.empty()) { 5245 if (Previous.isSingleResult() && 5246 isa<FieldDecl>(Previous.getFoundDecl()) && 5247 D.getCXXScopeSpec().isSet()) { 5248 // The user tried to define a non-static data member 5249 // out-of-line (C++ [dcl.meaning]p1). 5250 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 5251 << D.getCXXScopeSpec().getRange(); 5252 Previous.clear(); 5253 NewVD->setInvalidDecl(); 5254 } 5255 } else if (D.getCXXScopeSpec().isSet()) { 5256 // No previous declaration in the qualifying scope. 5257 Diag(D.getIdentifierLoc(), diag::err_no_member) 5258 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 5259 << D.getCXXScopeSpec().getRange(); 5260 NewVD->setInvalidDecl(); 5261 } 5262 5263 if (!IsVariableTemplateSpecialization) { 5264 if (PrevVarTemplate) { 5265 LookupResult PrevDecl(*this, GetNameForDeclarator(D), 5266 LookupOrdinaryName, ForRedeclaration); 5267 PrevDecl.addDecl(PrevVarTemplate->getTemplatedDecl()); 5268 D.setRedeclaration(CheckVariableDeclaration(NewVD, PrevDecl)); 5269 } else 5270 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous)); 5271 } 5272 5273 // This is an explicit specialization of a static data member. Check it. 5274 // FIXME: Special treatment for static variable template members (?). 5275 if (IsExplicitSpecialization && !NewVD->isInvalidDecl() && 5276 CheckMemberSpecialization(NewVD, Previous)) 5277 NewVD->setInvalidDecl(); 5278 } 5279 5280 ProcessPragmaWeak(S, NewVD); 5281 checkAttributesAfterMerging(*this, *NewVD); 5282 5283 // If this is the first declaration of an extern C variable, update 5284 // the map of such variables. 5285 if (!NewVD->getPreviousDecl() && !NewVD->isInvalidDecl() && 5286 isIncompleteDeclExternC(*this, NewVD)) 5287 RegisterLocallyScopedExternCDecl(NewVD, S); 5288 5289 if (NewVD->isStaticLocal()) { 5290 Decl *ManglingContextDecl; 5291 if (MangleNumberingContext *MCtx = 5292 getCurrentMangleNumberContext(NewVD->getDeclContext(), 5293 ManglingContextDecl)) { 5294 Context.setManglingNumber(NewVD, MCtx->getManglingNumber(NewVD)); 5295 } 5296 } 5297 5298 // If this is not a variable template, return it now 5299 if (!TemplateParams || IsVariableTemplateSpecialization) 5300 return NewVD; 5301 5302 // If this is supposed to be a variable template, create it as such. 5303 VarTemplateDecl *NewTemplate = 5304 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name, 5305 TemplateParams, NewVD, PrevVarTemplate); 5306 NewVD->setDescribedVarTemplate(NewTemplate); 5307 5308 if (D.getDeclSpec().isModulePrivateSpecified()) 5309 NewTemplate->setModulePrivate(); 5310 5311 // If we are providing an explicit specialization of a static variable 5312 // template, make a note of that. 5313 if (PrevVarTemplate && PrevVarTemplate->getInstantiatedFromMemberTemplate()) 5314 NewTemplate->setMemberSpecialization(); 5315 5316 // Set the lexical context of this template 5317 NewTemplate->setLexicalDeclContext(CurContext); 5318 if (NewVD->isStaticDataMember() && NewVD->isOutOfLine()) 5319 NewTemplate->setAccess(NewVD->getAccess()); 5320 5321 if (PrevVarTemplate) 5322 mergeDeclAttributes(NewVD, PrevVarTemplate->getTemplatedDecl()); 5323 5324 AddPushedVisibilityAttribute(NewVD); 5325 5326 PushOnScopeChains(NewTemplate, S); 5327 AddToScope = false; 5328 5329 if (Invalid) { 5330 NewTemplate->setInvalidDecl(); 5331 NewVD->setInvalidDecl(); 5332 } 5333 5334 ActOnDocumentableDecl(NewTemplate); 5335 5336 return NewTemplate; 5337 } 5338 5339 /// \brief Diagnose variable or built-in function shadowing. Implements 5340 /// -Wshadow. 5341 /// 5342 /// This method is called whenever a VarDecl is added to a "useful" 5343 /// scope. 5344 /// 5345 /// \param S the scope in which the shadowing name is being declared 5346 /// \param R the lookup of the name 5347 /// 5348 void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 5349 // Return if warning is ignored. 5350 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 5351 DiagnosticsEngine::Ignored) 5352 return; 5353 5354 // Don't diagnose declarations at file scope. 5355 if (D->hasGlobalStorage()) 5356 return; 5357 5358 DeclContext *NewDC = D->getDeclContext(); 5359 5360 // Only diagnose if we're shadowing an unambiguous field or variable. 5361 if (R.getResultKind() != LookupResult::Found) 5362 return; 5363 5364 NamedDecl* ShadowedDecl = R.getFoundDecl(); 5365 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 5366 return; 5367 5368 // Fields are not shadowed by variables in C++ static methods. 5369 if (isa<FieldDecl>(ShadowedDecl)) 5370 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 5371 if (MD->isStatic()) 5372 return; 5373 5374 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 5375 if (shadowedVar->isExternC()) { 5376 // For shadowing external vars, make sure that we point to the global 5377 // declaration, not a locally scoped extern declaration. 5378 for (VarDecl::redecl_iterator 5379 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 5380 I != E; ++I) 5381 if (I->isFileVarDecl()) { 5382 ShadowedDecl = *I; 5383 break; 5384 } 5385 } 5386 5387 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 5388 5389 // Only warn about certain kinds of shadowing for class members. 5390 if (NewDC && NewDC->isRecord()) { 5391 // In particular, don't warn about shadowing non-class members. 5392 if (!OldDC->isRecord()) 5393 return; 5394 5395 // TODO: should we warn about static data members shadowing 5396 // static data members from base classes? 5397 5398 // TODO: don't diagnose for inaccessible shadowed members. 5399 // This is hard to do perfectly because we might friend the 5400 // shadowing context, but that's just a false negative. 5401 } 5402 5403 // Determine what kind of declaration we're shadowing. 5404 unsigned Kind; 5405 if (isa<RecordDecl>(OldDC)) { 5406 if (isa<FieldDecl>(ShadowedDecl)) 5407 Kind = 3; // field 5408 else 5409 Kind = 2; // static data member 5410 } else if (OldDC->isFileContext()) 5411 Kind = 1; // global 5412 else 5413 Kind = 0; // local 5414 5415 DeclarationName Name = R.getLookupName(); 5416 5417 // Emit warning and note. 5418 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 5419 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 5420 } 5421 5422 /// \brief Check -Wshadow without the advantage of a previous lookup. 5423 void Sema::CheckShadow(Scope *S, VarDecl *D) { 5424 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 5425 DiagnosticsEngine::Ignored) 5426 return; 5427 5428 LookupResult R(*this, D->getDeclName(), D->getLocation(), 5429 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 5430 LookupName(R, S); 5431 CheckShadow(S, D, R); 5432 } 5433 5434 /// Check for conflict between this global or extern "C" declaration and 5435 /// previous global or extern "C" declarations. This is only used in C++. 5436 template<typename T> 5437 static bool checkGlobalOrExternCConflict( 5438 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) { 5439 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\""); 5440 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName()); 5441 5442 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) { 5443 // The common case: this global doesn't conflict with any extern "C" 5444 // declaration. 5445 return false; 5446 } 5447 5448 if (Prev) { 5449 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) { 5450 // Both the old and new declarations have C language linkage. This is a 5451 // redeclaration. 5452 Previous.clear(); 5453 Previous.addDecl(Prev); 5454 return true; 5455 } 5456 5457 // This is a global, non-extern "C" declaration, and there is a previous 5458 // non-global extern "C" declaration. Diagnose if this is a variable 5459 // declaration. 5460 if (!isa<VarDecl>(ND)) 5461 return false; 5462 } else { 5463 // The declaration is extern "C". Check for any declaration in the 5464 // translation unit which might conflict. 5465 if (IsGlobal) { 5466 // We have already performed the lookup into the translation unit. 5467 IsGlobal = false; 5468 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 5469 I != E; ++I) { 5470 if (isa<VarDecl>(*I)) { 5471 Prev = *I; 5472 break; 5473 } 5474 } 5475 } else { 5476 DeclContext::lookup_result R = 5477 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName()); 5478 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end(); 5479 I != E; ++I) { 5480 if (isa<VarDecl>(*I)) { 5481 Prev = *I; 5482 break; 5483 } 5484 // FIXME: If we have any other entity with this name in global scope, 5485 // the declaration is ill-formed, but that is a defect: it breaks the 5486 // 'stat' hack, for instance. Only variables can have mangled name 5487 // clashes with extern "C" declarations, so only they deserve a 5488 // diagnostic. 5489 } 5490 } 5491 5492 if (!Prev) 5493 return false; 5494 } 5495 5496 // Use the first declaration's location to ensure we point at something which 5497 // is lexically inside an extern "C" linkage-spec. 5498 assert(Prev && "should have found a previous declaration to diagnose"); 5499 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev)) 5500 Prev = FD->getFirstDeclaration(); 5501 else 5502 Prev = cast<VarDecl>(Prev)->getFirstDeclaration(); 5503 5504 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict) 5505 << IsGlobal << ND; 5506 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict) 5507 << IsGlobal; 5508 return false; 5509 } 5510 5511 /// Apply special rules for handling extern "C" declarations. Returns \c true 5512 /// if we have found that this is a redeclaration of some prior entity. 5513 /// 5514 /// Per C++ [dcl.link]p6: 5515 /// Two declarations [for a function or variable] with C language linkage 5516 /// with the same name that appear in different scopes refer to the same 5517 /// [entity]. An entity with C language linkage shall not be declared with 5518 /// the same name as an entity in global scope. 5519 template<typename T> 5520 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND, 5521 LookupResult &Previous) { 5522 if (!S.getLangOpts().CPlusPlus) { 5523 // In C, when declaring a global variable, look for a corresponding 'extern' 5524 // variable declared in function scope. 5525 // 5526 // FIXME: The corresponding case in C++ does not work. We should instead 5527 // set the semantic DC for an extern local variable to be the innermost 5528 // enclosing namespace, and ensure they are only found by redeclaration 5529 // lookup. 5530 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 5531 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) { 5532 Previous.clear(); 5533 Previous.addDecl(Prev); 5534 return true; 5535 } 5536 } 5537 return false; 5538 } 5539 5540 // A declaration in the translation unit can conflict with an extern "C" 5541 // declaration. 5542 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) 5543 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous); 5544 5545 // An extern "C" declaration can conflict with a declaration in the 5546 // translation unit or can be a redeclaration of an extern "C" declaration 5547 // in another scope. 5548 if (isIncompleteDeclExternC(S,ND)) 5549 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous); 5550 5551 // Neither global nor extern "C": nothing to do. 5552 return false; 5553 } 5554 5555 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) { 5556 // If the decl is already known invalid, don't check it. 5557 if (NewVD->isInvalidDecl()) 5558 return; 5559 5560 TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo(); 5561 QualType T = TInfo->getType(); 5562 5563 // Defer checking an 'auto' type until its initializer is attached. 5564 if (T->isUndeducedType()) 5565 return; 5566 5567 if (T->isObjCObjectType()) { 5568 Diag(NewVD->getLocation(), diag::err_statically_allocated_object) 5569 << FixItHint::CreateInsertion(NewVD->getLocation(), "*"); 5570 T = Context.getObjCObjectPointerType(T); 5571 NewVD->setType(T); 5572 } 5573 5574 // Emit an error if an address space was applied to decl with local storage. 5575 // This includes arrays of objects with address space qualifiers, but not 5576 // automatic variables that point to other address spaces. 5577 // ISO/IEC TR 18037 S5.1.2 5578 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 5579 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 5580 NewVD->setInvalidDecl(); 5581 return; 5582 } 5583 5584 // OpenCL v1.2 s6.5 - All program scope variables must be declared in the 5585 // __constant address space. 5586 if (getLangOpts().OpenCL && NewVD->isFileVarDecl() 5587 && T.getAddressSpace() != LangAS::opencl_constant 5588 && !T->isSamplerT()){ 5589 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space); 5590 NewVD->setInvalidDecl(); 5591 return; 5592 } 5593 5594 // OpenCL v1.2 s6.8 -- The static qualifier is valid only in program 5595 // scope. 5596 if ((getLangOpts().OpenCLVersion >= 120) 5597 && NewVD->isStaticLocal()) { 5598 Diag(NewVD->getLocation(), diag::err_static_function_scope); 5599 NewVD->setInvalidDecl(); 5600 return; 5601 } 5602 5603 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 5604 && !NewVD->hasAttr<BlocksAttr>()) { 5605 if (getLangOpts().getGC() != LangOptions::NonGC) 5606 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local); 5607 else { 5608 assert(!getLangOpts().ObjCAutoRefCount); 5609 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 5610 } 5611 } 5612 5613 bool isVM = T->isVariablyModifiedType(); 5614 if (isVM || NewVD->hasAttr<CleanupAttr>() || 5615 NewVD->hasAttr<BlocksAttr>()) 5616 getCurFunction()->setHasBranchProtectedScope(); 5617 5618 if ((isVM && NewVD->hasLinkage()) || 5619 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 5620 bool SizeIsNegative; 5621 llvm::APSInt Oversized; 5622 TypeSourceInfo *FixedTInfo = 5623 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context, 5624 SizeIsNegative, Oversized); 5625 if (FixedTInfo == 0 && T->isVariableArrayType()) { 5626 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 5627 // FIXME: This won't give the correct result for 5628 // int a[10][n]; 5629 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 5630 5631 if (NewVD->isFileVarDecl()) 5632 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 5633 << SizeRange; 5634 else if (NewVD->isStaticLocal()) 5635 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 5636 << SizeRange; 5637 else 5638 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 5639 << SizeRange; 5640 NewVD->setInvalidDecl(); 5641 return; 5642 } 5643 5644 if (FixedTInfo == 0) { 5645 if (NewVD->isFileVarDecl()) 5646 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 5647 else 5648 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 5649 NewVD->setInvalidDecl(); 5650 return; 5651 } 5652 5653 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 5654 NewVD->setType(FixedTInfo->getType()); 5655 NewVD->setTypeSourceInfo(FixedTInfo); 5656 } 5657 5658 if (T->isVoidType()) { 5659 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names 5660 // of objects and functions. 5661 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) { 5662 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 5663 << T; 5664 NewVD->setInvalidDecl(); 5665 return; 5666 } 5667 } 5668 5669 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 5670 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 5671 NewVD->setInvalidDecl(); 5672 return; 5673 } 5674 5675 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 5676 Diag(NewVD->getLocation(), diag::err_block_on_vm); 5677 NewVD->setInvalidDecl(); 5678 return; 5679 } 5680 5681 if (NewVD->isConstexpr() && !T->isDependentType() && 5682 RequireLiteralType(NewVD->getLocation(), T, 5683 diag::err_constexpr_var_non_literal)) { 5684 // Can't perform this check until the type is deduced. 5685 NewVD->setInvalidDecl(); 5686 return; 5687 } 5688 } 5689 5690 /// \brief Perform semantic checking on a newly-created variable 5691 /// declaration. 5692 /// 5693 /// This routine performs all of the type-checking required for a 5694 /// variable declaration once it has been built. It is used both to 5695 /// check variables after they have been parsed and their declarators 5696 /// have been translated into a declaration, and to check variables 5697 /// that have been instantiated from a template. 5698 /// 5699 /// Sets NewVD->isInvalidDecl() if an error was encountered. 5700 /// 5701 /// Returns true if the variable declaration is a redeclaration. 5702 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, 5703 LookupResult &Previous) { 5704 CheckVariableDeclarationType(NewVD); 5705 5706 // If the decl is already known invalid, don't check it. 5707 if (NewVD->isInvalidDecl()) 5708 return false; 5709 5710 // If we did not find anything by this name, look for a non-visible 5711 // extern "C" declaration with the same name. 5712 // 5713 // Clang has a lot of problems with extern local declarations. 5714 // The actual standards text here is: 5715 // 5716 // C++11 [basic.link]p6: 5717 // The name of a function declared in block scope and the name 5718 // of a variable declared by a block scope extern declaration 5719 // have linkage. If there is a visible declaration of an entity 5720 // with linkage having the same name and type, ignoring entities 5721 // declared outside the innermost enclosing namespace scope, the 5722 // block scope declaration declares that same entity and 5723 // receives the linkage of the previous declaration. 5724 // 5725 // C11 6.2.7p4: 5726 // For an identifier with internal or external linkage declared 5727 // in a scope in which a prior declaration of that identifier is 5728 // visible, if the prior declaration specifies internal or 5729 // external linkage, the type of the identifier at the later 5730 // declaration becomes the composite type. 5731 // 5732 // The most important point here is that we're not allowed to 5733 // update our understanding of the type according to declarations 5734 // not in scope. 5735 bool PreviousWasHidden = 5736 Previous.empty() && 5737 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous); 5738 5739 // Filter out any non-conflicting previous declarations. 5740 filterNonConflictingPreviousDecls(Context, NewVD, Previous); 5741 5742 if (!Previous.empty()) { 5743 MergeVarDecl(NewVD, Previous, PreviousWasHidden); 5744 return true; 5745 } 5746 return false; 5747 } 5748 5749 /// \brief Data used with FindOverriddenMethod 5750 struct FindOverriddenMethodData { 5751 Sema *S; 5752 CXXMethodDecl *Method; 5753 }; 5754 5755 /// \brief Member lookup function that determines whether a given C++ 5756 /// method overrides a method in a base class, to be used with 5757 /// CXXRecordDecl::lookupInBases(). 5758 static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 5759 CXXBasePath &Path, 5760 void *UserData) { 5761 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 5762 5763 FindOverriddenMethodData *Data 5764 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 5765 5766 DeclarationName Name = Data->Method->getDeclName(); 5767 5768 // FIXME: Do we care about other names here too? 5769 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 5770 // We really want to find the base class destructor here. 5771 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 5772 CanQualType CT = Data->S->Context.getCanonicalType(T); 5773 5774 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 5775 } 5776 5777 for (Path.Decls = BaseRecord->lookup(Name); 5778 !Path.Decls.empty(); 5779 Path.Decls = Path.Decls.slice(1)) { 5780 NamedDecl *D = Path.Decls.front(); 5781 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 5782 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 5783 return true; 5784 } 5785 } 5786 5787 return false; 5788 } 5789 5790 namespace { 5791 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted }; 5792 } 5793 /// \brief Report an error regarding overriding, along with any relevant 5794 /// overriden methods. 5795 /// 5796 /// \param DiagID the primary error to report. 5797 /// \param MD the overriding method. 5798 /// \param OEK which overrides to include as notes. 5799 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD, 5800 OverrideErrorKind OEK = OEK_All) { 5801 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName(); 5802 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(), 5803 E = MD->end_overridden_methods(); 5804 I != E; ++I) { 5805 // This check (& the OEK parameter) could be replaced by a predicate, but 5806 // without lambdas that would be overkill. This is still nicer than writing 5807 // out the diag loop 3 times. 5808 if ((OEK == OEK_All) || 5809 (OEK == OEK_NonDeleted && !(*I)->isDeleted()) || 5810 (OEK == OEK_Deleted && (*I)->isDeleted())) 5811 S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function); 5812 } 5813 } 5814 5815 /// AddOverriddenMethods - See if a method overrides any in the base classes, 5816 /// and if so, check that it's a valid override and remember it. 5817 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 5818 // Look for virtual methods in base classes that this method might override. 5819 CXXBasePaths Paths; 5820 FindOverriddenMethodData Data; 5821 Data.Method = MD; 5822 Data.S = this; 5823 bool hasDeletedOverridenMethods = false; 5824 bool hasNonDeletedOverridenMethods = false; 5825 bool AddedAny = false; 5826 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 5827 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 5828 E = Paths.found_decls_end(); I != E; ++I) { 5829 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 5830 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 5831 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 5832 !CheckOverridingFunctionAttributes(MD, OldMD) && 5833 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 5834 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 5835 hasDeletedOverridenMethods |= OldMD->isDeleted(); 5836 hasNonDeletedOverridenMethods |= !OldMD->isDeleted(); 5837 AddedAny = true; 5838 } 5839 } 5840 } 5841 } 5842 5843 if (hasDeletedOverridenMethods && !MD->isDeleted()) { 5844 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted); 5845 } 5846 if (hasNonDeletedOverridenMethods && MD->isDeleted()) { 5847 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted); 5848 } 5849 5850 return AddedAny; 5851 } 5852 5853 namespace { 5854 // Struct for holding all of the extra arguments needed by 5855 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator. 5856 struct ActOnFDArgs { 5857 Scope *S; 5858 Declarator &D; 5859 MultiTemplateParamsArg TemplateParamLists; 5860 bool AddToScope; 5861 }; 5862 } 5863 5864 namespace { 5865 5866 // Callback to only accept typo corrections that have a non-zero edit distance. 5867 // Also only accept corrections that have the same parent decl. 5868 class DifferentNameValidatorCCC : public CorrectionCandidateCallback { 5869 public: 5870 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD, 5871 CXXRecordDecl *Parent) 5872 : Context(Context), OriginalFD(TypoFD), 5873 ExpectedParent(Parent ? Parent->getCanonicalDecl() : 0) {} 5874 5875 virtual bool ValidateCandidate(const TypoCorrection &candidate) { 5876 if (candidate.getEditDistance() == 0) 5877 return false; 5878 5879 SmallVector<unsigned, 1> MismatchedParams; 5880 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(), 5881 CDeclEnd = candidate.end(); 5882 CDecl != CDeclEnd; ++CDecl) { 5883 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl); 5884 5885 if (FD && !FD->hasBody() && 5886 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) { 5887 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 5888 CXXRecordDecl *Parent = MD->getParent(); 5889 if (Parent && Parent->getCanonicalDecl() == ExpectedParent) 5890 return true; 5891 } else if (!ExpectedParent) { 5892 return true; 5893 } 5894 } 5895 } 5896 5897 return false; 5898 } 5899 5900 private: 5901 ASTContext &Context; 5902 FunctionDecl *OriginalFD; 5903 CXXRecordDecl *ExpectedParent; 5904 }; 5905 5906 } 5907 5908 /// \brief Generate diagnostics for an invalid function redeclaration. 5909 /// 5910 /// This routine handles generating the diagnostic messages for an invalid 5911 /// function redeclaration, including finding possible similar declarations 5912 /// or performing typo correction if there are no previous declarations with 5913 /// the same name. 5914 /// 5915 /// Returns a NamedDecl iff typo correction was performed and substituting in 5916 /// the new declaration name does not cause new errors. 5917 static NamedDecl* DiagnoseInvalidRedeclaration( 5918 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD, 5919 ActOnFDArgs &ExtraArgs) { 5920 NamedDecl *Result = NULL; 5921 DeclarationName Name = NewFD->getDeclName(); 5922 DeclContext *NewDC = NewFD->getDeclContext(); 5923 LookupResult Prev(SemaRef, Name, NewFD->getLocation(), 5924 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 5925 SmallVector<unsigned, 1> MismatchedParams; 5926 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches; 5927 TypoCorrection Correction; 5928 bool isFriendDecl = (SemaRef.getLangOpts().CPlusPlus && 5929 ExtraArgs.D.getDeclSpec().isFriendSpecified()); 5930 unsigned DiagMsg = isFriendDecl ? diag::err_no_matching_local_friend 5931 : diag::err_member_def_does_not_match; 5932 5933 NewFD->setInvalidDecl(); 5934 SemaRef.LookupQualifiedName(Prev, NewDC); 5935 assert(!Prev.isAmbiguous() && 5936 "Cannot have an ambiguity in previous-declaration lookup"); 5937 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD); 5938 DifferentNameValidatorCCC Validator(SemaRef.Context, NewFD, 5939 MD ? MD->getParent() : 0); 5940 if (!Prev.empty()) { 5941 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 5942 Func != FuncEnd; ++Func) { 5943 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func); 5944 if (FD && 5945 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) { 5946 // Add 1 to the index so that 0 can mean the mismatch didn't 5947 // involve a parameter 5948 unsigned ParamNum = 5949 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1; 5950 NearMatches.push_back(std::make_pair(FD, ParamNum)); 5951 } 5952 } 5953 // If the qualified name lookup yielded nothing, try typo correction 5954 } else if ((Correction = SemaRef.CorrectTypo(Prev.getLookupNameInfo(), 5955 Prev.getLookupKind(), 0, 0, 5956 Validator, NewDC))) { 5957 // Trap errors. 5958 Sema::SFINAETrap Trap(SemaRef); 5959 5960 // Set up everything for the call to ActOnFunctionDeclarator 5961 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(), 5962 ExtraArgs.D.getIdentifierLoc()); 5963 Previous.clear(); 5964 Previous.setLookupName(Correction.getCorrection()); 5965 for (TypoCorrection::decl_iterator CDecl = Correction.begin(), 5966 CDeclEnd = Correction.end(); 5967 CDecl != CDeclEnd; ++CDecl) { 5968 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl); 5969 if (FD && !FD->hasBody() && 5970 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) { 5971 Previous.addDecl(FD); 5972 } 5973 } 5974 bool wasRedeclaration = ExtraArgs.D.isRedeclaration(); 5975 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the 5976 // pieces need to verify the typo-corrected C++ declaraction and hopefully 5977 // eliminate the need for the parameter pack ExtraArgs. 5978 Result = SemaRef.ActOnFunctionDeclarator( 5979 ExtraArgs.S, ExtraArgs.D, 5980 Correction.getCorrectionDecl()->getDeclContext(), 5981 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists, 5982 ExtraArgs.AddToScope); 5983 if (Trap.hasErrorOccurred()) { 5984 // Pretend the typo correction never occurred 5985 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(), 5986 ExtraArgs.D.getIdentifierLoc()); 5987 ExtraArgs.D.setRedeclaration(wasRedeclaration); 5988 Previous.clear(); 5989 Previous.setLookupName(Name); 5990 Result = NULL; 5991 } else { 5992 for (LookupResult::iterator Func = Previous.begin(), 5993 FuncEnd = Previous.end(); 5994 Func != FuncEnd; ++Func) { 5995 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func)) 5996 NearMatches.push_back(std::make_pair(FD, 0)); 5997 } 5998 } 5999 if (NearMatches.empty()) { 6000 // Ignore the correction if it didn't yield any close FunctionDecl matches 6001 Correction = TypoCorrection(); 6002 } else { 6003 DiagMsg = isFriendDecl ? diag::err_no_matching_local_friend_suggest 6004 : diag::err_member_def_does_not_match_suggest; 6005 } 6006 } 6007 6008 if (Correction) { 6009 // FIXME: use Correction.getCorrectionRange() instead of computing the range 6010 // here. This requires passing in the CXXScopeSpec to CorrectTypo which in 6011 // turn causes the correction to fully qualify the name. If we fix 6012 // CorrectTypo to minimally qualify then this change should be good. 6013 SourceRange FixItLoc(NewFD->getLocation()); 6014 CXXScopeSpec &SS = ExtraArgs.D.getCXXScopeSpec(); 6015 if (Correction.getCorrectionSpecifier() && SS.isValid()) 6016 FixItLoc.setBegin(SS.getBeginLoc()); 6017 SemaRef.Diag(NewFD->getLocStart(), DiagMsg) 6018 << Name << NewDC << Correction.getQuoted(SemaRef.getLangOpts()) 6019 << FixItHint::CreateReplacement( 6020 FixItLoc, Correction.getAsString(SemaRef.getLangOpts())); 6021 } else { 6022 SemaRef.Diag(NewFD->getLocation(), DiagMsg) 6023 << Name << NewDC << NewFD->getLocation(); 6024 } 6025 6026 bool NewFDisConst = false; 6027 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) 6028 NewFDisConst = NewMD->isConst(); 6029 6030 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator 6031 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end(); 6032 NearMatch != NearMatchEnd; ++NearMatch) { 6033 FunctionDecl *FD = NearMatch->first; 6034 bool FDisConst = false; 6035 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) 6036 FDisConst = MD->isConst(); 6037 6038 if (unsigned Idx = NearMatch->second) { 6039 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1); 6040 SourceLocation Loc = FDParam->getTypeSpecStartLoc(); 6041 if (Loc.isInvalid()) Loc = FD->getLocation(); 6042 SemaRef.Diag(Loc, diag::note_member_def_close_param_match) 6043 << Idx << FDParam->getType() << NewFD->getParamDecl(Idx-1)->getType(); 6044 } else if (Correction) { 6045 SemaRef.Diag(FD->getLocation(), diag::note_previous_decl) 6046 << Correction.getQuoted(SemaRef.getLangOpts()); 6047 } else if (FDisConst != NewFDisConst) { 6048 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match) 6049 << NewFDisConst << FD->getSourceRange().getEnd(); 6050 } else 6051 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_match); 6052 } 6053 return Result; 6054 } 6055 6056 static FunctionDecl::StorageClass getFunctionStorageClass(Sema &SemaRef, 6057 Declarator &D) { 6058 switch (D.getDeclSpec().getStorageClassSpec()) { 6059 default: llvm_unreachable("Unknown storage class!"); 6060 case DeclSpec::SCS_auto: 6061 case DeclSpec::SCS_register: 6062 case DeclSpec::SCS_mutable: 6063 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(), 6064 diag::err_typecheck_sclass_func); 6065 D.setInvalidType(); 6066 break; 6067 case DeclSpec::SCS_unspecified: break; 6068 case DeclSpec::SCS_extern: 6069 if (D.getDeclSpec().isExternInLinkageSpec()) 6070 return SC_None; 6071 return SC_Extern; 6072 case DeclSpec::SCS_static: { 6073 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) { 6074 // C99 6.7.1p5: 6075 // The declaration of an identifier for a function that has 6076 // block scope shall have no explicit storage-class specifier 6077 // other than extern 6078 // See also (C++ [dcl.stc]p4). 6079 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(), 6080 diag::err_static_block_func); 6081 break; 6082 } else 6083 return SC_Static; 6084 } 6085 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 6086 } 6087 6088 // No explicit storage class has already been returned 6089 return SC_None; 6090 } 6091 6092 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D, 6093 DeclContext *DC, QualType &R, 6094 TypeSourceInfo *TInfo, 6095 FunctionDecl::StorageClass SC, 6096 bool &IsVirtualOkay) { 6097 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D); 6098 DeclarationName Name = NameInfo.getName(); 6099 6100 FunctionDecl *NewFD = 0; 6101 bool isInline = D.getDeclSpec().isInlineSpecified(); 6102 6103 if (!SemaRef.getLangOpts().CPlusPlus) { 6104 // Determine whether the function was written with a 6105 // prototype. This true when: 6106 // - there is a prototype in the declarator, or 6107 // - the type R of the function is some kind of typedef or other reference 6108 // to a type name (which eventually refers to a function type). 6109 bool HasPrototype = 6110 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 6111 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 6112 6113 NewFD = FunctionDecl::Create(SemaRef.Context, DC, 6114 D.getLocStart(), NameInfo, R, 6115 TInfo, SC, isInline, 6116 HasPrototype, false); 6117 if (D.isInvalidType()) 6118 NewFD->setInvalidDecl(); 6119 6120 // Set the lexical context. 6121 NewFD->setLexicalDeclContext(SemaRef.CurContext); 6122 6123 return NewFD; 6124 } 6125 6126 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 6127 bool isConstexpr = D.getDeclSpec().isConstexprSpecified(); 6128 6129 // Check that the return type is not an abstract class type. 6130 // For record types, this is done by the AbstractClassUsageDiagnoser once 6131 // the class has been completely parsed. 6132 if (!DC->isRecord() && 6133 SemaRef.RequireNonAbstractType(D.getIdentifierLoc(), 6134 R->getAs<FunctionType>()->getResultType(), 6135 diag::err_abstract_type_in_decl, 6136 SemaRef.AbstractReturnType)) 6137 D.setInvalidType(); 6138 6139 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 6140 // This is a C++ constructor declaration. 6141 assert(DC->isRecord() && 6142 "Constructors can only be declared in a member context"); 6143 6144 R = SemaRef.CheckConstructorDeclarator(D, R, SC); 6145 return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC), 6146 D.getLocStart(), NameInfo, 6147 R, TInfo, isExplicit, isInline, 6148 /*isImplicitlyDeclared=*/false, 6149 isConstexpr); 6150 6151 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 6152 // This is a C++ destructor declaration. 6153 if (DC->isRecord()) { 6154 R = SemaRef.CheckDestructorDeclarator(D, R, SC); 6155 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 6156 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create( 6157 SemaRef.Context, Record, 6158 D.getLocStart(), 6159 NameInfo, R, TInfo, isInline, 6160 /*isImplicitlyDeclared=*/false); 6161 6162 // If the class is complete, then we now create the implicit exception 6163 // specification. If the class is incomplete or dependent, we can't do 6164 // it yet. 6165 if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() && 6166 Record->getDefinition() && !Record->isBeingDefined() && 6167 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) { 6168 SemaRef.AdjustDestructorExceptionSpec(Record, NewDD); 6169 } 6170 6171 // The Microsoft ABI requires that we perform the destructor body 6172 // checks (i.e. operator delete() lookup) at every declaration, as 6173 // any translation unit may need to emit a deleting destructor. 6174 if (SemaRef.Context.getTargetInfo().getCXXABI().isMicrosoft() && 6175 !Record->isDependentType() && Record->getDefinition() && 6176 !Record->isBeingDefined()) { 6177 SemaRef.CheckDestructor(NewDD); 6178 } 6179 6180 IsVirtualOkay = true; 6181 return NewDD; 6182 6183 } else { 6184 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 6185 D.setInvalidType(); 6186 6187 // Create a FunctionDecl to satisfy the function definition parsing 6188 // code path. 6189 return FunctionDecl::Create(SemaRef.Context, DC, 6190 D.getLocStart(), 6191 D.getIdentifierLoc(), Name, R, TInfo, 6192 SC, isInline, 6193 /*hasPrototype=*/true, isConstexpr); 6194 } 6195 6196 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 6197 if (!DC->isRecord()) { 6198 SemaRef.Diag(D.getIdentifierLoc(), 6199 diag::err_conv_function_not_member); 6200 return 0; 6201 } 6202 6203 SemaRef.CheckConversionDeclarator(D, R, SC); 6204 IsVirtualOkay = true; 6205 return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC), 6206 D.getLocStart(), NameInfo, 6207 R, TInfo, isInline, isExplicit, 6208 isConstexpr, SourceLocation()); 6209 6210 } else if (DC->isRecord()) { 6211 // If the name of the function is the same as the name of the record, 6212 // then this must be an invalid constructor that has a return type. 6213 // (The parser checks for a return type and makes the declarator a 6214 // constructor if it has no return type). 6215 if (Name.getAsIdentifierInfo() && 6216 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 6217 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 6218 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 6219 << SourceRange(D.getIdentifierLoc()); 6220 return 0; 6221 } 6222 6223 // This is a C++ method declaration. 6224 CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context, 6225 cast<CXXRecordDecl>(DC), 6226 D.getLocStart(), NameInfo, R, 6227 TInfo, SC, isInline, 6228 isConstexpr, SourceLocation()); 6229 IsVirtualOkay = !Ret->isStatic(); 6230 return Ret; 6231 } else { 6232 // Determine whether the function was written with a 6233 // prototype. This true when: 6234 // - we're in C++ (where every function has a prototype), 6235 return FunctionDecl::Create(SemaRef.Context, DC, 6236 D.getLocStart(), 6237 NameInfo, R, TInfo, SC, isInline, 6238 true/*HasPrototype*/, isConstexpr); 6239 } 6240 } 6241 6242 void Sema::checkVoidParamDecl(ParmVarDecl *Param) { 6243 // In C++, the empty parameter-type-list must be spelled "void"; a 6244 // typedef of void is not permitted. 6245 if (getLangOpts().CPlusPlus && 6246 Param->getType().getUnqualifiedType() != Context.VoidTy) { 6247 bool IsTypeAlias = false; 6248 if (const TypedefType *TT = Param->getType()->getAs<TypedefType>()) 6249 IsTypeAlias = isa<TypeAliasDecl>(TT->getDecl()); 6250 else if (const TemplateSpecializationType *TST = 6251 Param->getType()->getAs<TemplateSpecializationType>()) 6252 IsTypeAlias = TST->isTypeAlias(); 6253 Diag(Param->getLocation(), diag::err_param_typedef_of_void) 6254 << IsTypeAlias; 6255 } 6256 } 6257 6258 enum OpenCLParamType { 6259 ValidKernelParam, 6260 PtrPtrKernelParam, 6261 PtrKernelParam, 6262 InvalidKernelParam, 6263 RecordKernelParam 6264 }; 6265 6266 static OpenCLParamType getOpenCLKernelParameterType(QualType PT) { 6267 if (PT->isPointerType()) { 6268 QualType PointeeType = PT->getPointeeType(); 6269 return PointeeType->isPointerType() ? PtrPtrKernelParam : PtrKernelParam; 6270 } 6271 6272 // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can 6273 // be used as builtin types. 6274 6275 if (PT->isImageType()) 6276 return PtrKernelParam; 6277 6278 if (PT->isBooleanType()) 6279 return InvalidKernelParam; 6280 6281 if (PT->isEventT()) 6282 return InvalidKernelParam; 6283 6284 if (PT->isHalfType()) 6285 return InvalidKernelParam; 6286 6287 if (PT->isRecordType()) 6288 return RecordKernelParam; 6289 6290 return ValidKernelParam; 6291 } 6292 6293 static void checkIsValidOpenCLKernelParameter( 6294 Sema &S, 6295 Declarator &D, 6296 ParmVarDecl *Param, 6297 llvm::SmallPtrSet<const Type *, 16> &ValidTypes) { 6298 QualType PT = Param->getType(); 6299 6300 // Cache the valid types we encounter to avoid rechecking structs that are 6301 // used again 6302 if (ValidTypes.count(PT.getTypePtr())) 6303 return; 6304 6305 switch (getOpenCLKernelParameterType(PT)) { 6306 case PtrPtrKernelParam: 6307 // OpenCL v1.2 s6.9.a: 6308 // A kernel function argument cannot be declared as a 6309 // pointer to a pointer type. 6310 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param); 6311 D.setInvalidType(); 6312 return; 6313 6314 // OpenCL v1.2 s6.9.k: 6315 // Arguments to kernel functions in a program cannot be declared with the 6316 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and 6317 // uintptr_t or a struct and/or union that contain fields declared to be 6318 // one of these built-in scalar types. 6319 6320 case InvalidKernelParam: 6321 // OpenCL v1.2 s6.8 n: 6322 // A kernel function argument cannot be declared 6323 // of event_t type. 6324 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT; 6325 D.setInvalidType(); 6326 return; 6327 6328 case PtrKernelParam: 6329 case ValidKernelParam: 6330 ValidTypes.insert(PT.getTypePtr()); 6331 return; 6332 6333 case RecordKernelParam: 6334 break; 6335 } 6336 6337 // Track nested structs we will inspect 6338 SmallVector<const Decl *, 4> VisitStack; 6339 6340 // Track where we are in the nested structs. Items will migrate from 6341 // VisitStack to HistoryStack as we do the DFS for bad field. 6342 SmallVector<const FieldDecl *, 4> HistoryStack; 6343 HistoryStack.push_back((const FieldDecl *) 0); 6344 6345 const RecordDecl *PD = PT->castAs<RecordType>()->getDecl(); 6346 VisitStack.push_back(PD); 6347 6348 assert(VisitStack.back() && "First decl null?"); 6349 6350 do { 6351 const Decl *Next = VisitStack.pop_back_val(); 6352 if (!Next) { 6353 assert(!HistoryStack.empty()); 6354 // Found a marker, we have gone up a level 6355 if (const FieldDecl *Hist = HistoryStack.pop_back_val()) 6356 ValidTypes.insert(Hist->getType().getTypePtr()); 6357 6358 continue; 6359 } 6360 6361 // Adds everything except the original parameter declaration (which is not a 6362 // field itself) to the history stack. 6363 const RecordDecl *RD; 6364 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) { 6365 HistoryStack.push_back(Field); 6366 RD = Field->getType()->castAs<RecordType>()->getDecl(); 6367 } else { 6368 RD = cast<RecordDecl>(Next); 6369 } 6370 6371 // Add a null marker so we know when we've gone back up a level 6372 VisitStack.push_back((const Decl *) 0); 6373 6374 for (RecordDecl::field_iterator I = RD->field_begin(), 6375 E = RD->field_end(); I != E; ++I) { 6376 const FieldDecl *FD = *I; 6377 QualType QT = FD->getType(); 6378 6379 if (ValidTypes.count(QT.getTypePtr())) 6380 continue; 6381 6382 OpenCLParamType ParamType = getOpenCLKernelParameterType(QT); 6383 if (ParamType == ValidKernelParam) 6384 continue; 6385 6386 if (ParamType == RecordKernelParam) { 6387 VisitStack.push_back(FD); 6388 continue; 6389 } 6390 6391 // OpenCL v1.2 s6.9.p: 6392 // Arguments to kernel functions that are declared to be a struct or union 6393 // do not allow OpenCL objects to be passed as elements of the struct or 6394 // union. 6395 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam) { 6396 S.Diag(Param->getLocation(), 6397 diag::err_record_with_pointers_kernel_param) 6398 << PT->isUnionType() 6399 << PT; 6400 } else { 6401 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT; 6402 } 6403 6404 S.Diag(PD->getLocation(), diag::note_within_field_of_type) 6405 << PD->getDeclName(); 6406 6407 // We have an error, now let's go back up through history and show where 6408 // the offending field came from 6409 for (ArrayRef<const FieldDecl *>::const_iterator I = HistoryStack.begin() + 1, 6410 E = HistoryStack.end(); I != E; ++I) { 6411 const FieldDecl *OuterField = *I; 6412 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type) 6413 << OuterField->getType(); 6414 } 6415 6416 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here) 6417 << QT->isPointerType() 6418 << QT; 6419 D.setInvalidType(); 6420 return; 6421 } 6422 } while (!VisitStack.empty()); 6423 } 6424 6425 NamedDecl* 6426 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC, 6427 TypeSourceInfo *TInfo, LookupResult &Previous, 6428 MultiTemplateParamsArg TemplateParamLists, 6429 bool &AddToScope) { 6430 QualType R = TInfo->getType(); 6431 6432 assert(R.getTypePtr()->isFunctionType()); 6433 6434 // TODO: consider using NameInfo for diagnostic. 6435 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 6436 DeclarationName Name = NameInfo.getName(); 6437 FunctionDecl::StorageClass SC = getFunctionStorageClass(*this, D); 6438 6439 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) 6440 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), 6441 diag::err_invalid_thread) 6442 << DeclSpec::getSpecifierName(TSCS); 6443 6444 bool isFriend = false; 6445 FunctionTemplateDecl *FunctionTemplate = 0; 6446 bool isExplicitSpecialization = false; 6447 bool isFunctionTemplateSpecialization = false; 6448 6449 bool isDependentClassScopeExplicitSpecialization = false; 6450 bool HasExplicitTemplateArgs = false; 6451 TemplateArgumentListInfo TemplateArgs; 6452 6453 bool isVirtualOkay = false; 6454 6455 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC, 6456 isVirtualOkay); 6457 if (!NewFD) return 0; 6458 6459 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer()) 6460 NewFD->setTopLevelDeclInObjCContainer(); 6461 6462 if (getLangOpts().CPlusPlus) { 6463 bool isInline = D.getDeclSpec().isInlineSpecified(); 6464 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 6465 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 6466 bool isConstexpr = D.getDeclSpec().isConstexprSpecified(); 6467 isFriend = D.getDeclSpec().isFriendSpecified(); 6468 if (isFriend && !isInline && D.isFunctionDefinition()) { 6469 // C++ [class.friend]p5 6470 // A function can be defined in a friend declaration of a 6471 // class . . . . Such a function is implicitly inline. 6472 NewFD->setImplicitlyInline(); 6473 } 6474 6475 // If this is a method defined in an __interface, and is not a constructor 6476 // or an overloaded operator, then set the pure flag (isVirtual will already 6477 // return true). 6478 if (const CXXRecordDecl *Parent = 6479 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) { 6480 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided()) 6481 NewFD->setPure(true); 6482 } 6483 6484 SetNestedNameSpecifier(NewFD, D); 6485 isExplicitSpecialization = false; 6486 isFunctionTemplateSpecialization = false; 6487 if (D.isInvalidType()) 6488 NewFD->setInvalidDecl(); 6489 6490 // Set the lexical context. If the declarator has a C++ 6491 // scope specifier, or is the object of a friend declaration, the 6492 // lexical context will be different from the semantic context. 6493 NewFD->setLexicalDeclContext(CurContext); 6494 6495 // Match up the template parameter lists with the scope specifier, then 6496 // determine whether we have a template or a template specialization. 6497 bool Invalid = false; 6498 if (TemplateParameterList *TemplateParams = 6499 MatchTemplateParametersToScopeSpecifier( 6500 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(), 6501 D.getCXXScopeSpec(), TemplateParamLists, isFriend, 6502 isExplicitSpecialization, Invalid)) { 6503 if (TemplateParams->size() > 0) { 6504 // This is a function template 6505 6506 // Check that we can declare a template here. 6507 if (CheckTemplateDeclScope(S, TemplateParams)) 6508 return 0; 6509 6510 // A destructor cannot be a template. 6511 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 6512 Diag(NewFD->getLocation(), diag::err_destructor_template); 6513 return 0; 6514 } 6515 6516 // If we're adding a template to a dependent context, we may need to 6517 // rebuilding some of the types used within the template parameter list, 6518 // now that we know what the current instantiation is. 6519 if (DC->isDependentContext()) { 6520 ContextRAII SavedContext(*this, DC); 6521 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams)) 6522 Invalid = true; 6523 } 6524 6525 6526 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 6527 NewFD->getLocation(), 6528 Name, TemplateParams, 6529 NewFD); 6530 FunctionTemplate->setLexicalDeclContext(CurContext); 6531 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 6532 6533 // For source fidelity, store the other template param lists. 6534 if (TemplateParamLists.size() > 1) { 6535 NewFD->setTemplateParameterListsInfo(Context, 6536 TemplateParamLists.size() - 1, 6537 TemplateParamLists.data()); 6538 } 6539 } else { 6540 // This is a function template specialization. 6541 isFunctionTemplateSpecialization = true; 6542 // For source fidelity, store all the template param lists. 6543 NewFD->setTemplateParameterListsInfo(Context, 6544 TemplateParamLists.size(), 6545 TemplateParamLists.data()); 6546 6547 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 6548 if (isFriend) { 6549 // We want to remove the "template<>", found here. 6550 SourceRange RemoveRange = TemplateParams->getSourceRange(); 6551 6552 // If we remove the template<> and the name is not a 6553 // template-id, we're actually silently creating a problem: 6554 // the friend declaration will refer to an untemplated decl, 6555 // and clearly the user wants a template specialization. So 6556 // we need to insert '<>' after the name. 6557 SourceLocation InsertLoc; 6558 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 6559 InsertLoc = D.getName().getSourceRange().getEnd(); 6560 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 6561 } 6562 6563 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 6564 << Name << RemoveRange 6565 << FixItHint::CreateRemoval(RemoveRange) 6566 << FixItHint::CreateInsertion(InsertLoc, "<>"); 6567 } 6568 } 6569 } 6570 else { 6571 // All template param lists were matched against the scope specifier: 6572 // this is NOT (an explicit specialization of) a template. 6573 if (TemplateParamLists.size() > 0) 6574 // For source fidelity, store all the template param lists. 6575 NewFD->setTemplateParameterListsInfo(Context, 6576 TemplateParamLists.size(), 6577 TemplateParamLists.data()); 6578 } 6579 6580 if (Invalid) { 6581 NewFD->setInvalidDecl(); 6582 if (FunctionTemplate) 6583 FunctionTemplate->setInvalidDecl(); 6584 } 6585 6586 // C++ [dcl.fct.spec]p5: 6587 // The virtual specifier shall only be used in declarations of 6588 // nonstatic class member functions that appear within a 6589 // member-specification of a class declaration; see 10.3. 6590 // 6591 if (isVirtual && !NewFD->isInvalidDecl()) { 6592 if (!isVirtualOkay) { 6593 Diag(D.getDeclSpec().getVirtualSpecLoc(), 6594 diag::err_virtual_non_function); 6595 } else if (!CurContext->isRecord()) { 6596 // 'virtual' was specified outside of the class. 6597 Diag(D.getDeclSpec().getVirtualSpecLoc(), 6598 diag::err_virtual_out_of_class) 6599 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 6600 } else if (NewFD->getDescribedFunctionTemplate()) { 6601 // C++ [temp.mem]p3: 6602 // A member function template shall not be virtual. 6603 Diag(D.getDeclSpec().getVirtualSpecLoc(), 6604 diag::err_virtual_member_function_template) 6605 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 6606 } else { 6607 // Okay: Add virtual to the method. 6608 NewFD->setVirtualAsWritten(true); 6609 } 6610 6611 if (getLangOpts().CPlusPlus1y && 6612 NewFD->getResultType()->isUndeducedType()) 6613 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual); 6614 } 6615 6616 // C++ [dcl.fct.spec]p3: 6617 // The inline specifier shall not appear on a block scope function 6618 // declaration. 6619 if (isInline && !NewFD->isInvalidDecl()) { 6620 if (CurContext->isFunctionOrMethod()) { 6621 // 'inline' is not allowed on block scope function declaration. 6622 Diag(D.getDeclSpec().getInlineSpecLoc(), 6623 diag::err_inline_declaration_block_scope) << Name 6624 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 6625 } 6626 } 6627 6628 // C++ [dcl.fct.spec]p6: 6629 // The explicit specifier shall be used only in the declaration of a 6630 // constructor or conversion function within its class definition; 6631 // see 12.3.1 and 12.3.2. 6632 if (isExplicit && !NewFD->isInvalidDecl()) { 6633 if (!CurContext->isRecord()) { 6634 // 'explicit' was specified outside of the class. 6635 Diag(D.getDeclSpec().getExplicitSpecLoc(), 6636 diag::err_explicit_out_of_class) 6637 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 6638 } else if (!isa<CXXConstructorDecl>(NewFD) && 6639 !isa<CXXConversionDecl>(NewFD)) { 6640 // 'explicit' was specified on a function that wasn't a constructor 6641 // or conversion function. 6642 Diag(D.getDeclSpec().getExplicitSpecLoc(), 6643 diag::err_explicit_non_ctor_or_conv_function) 6644 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 6645 } 6646 } 6647 6648 if (isConstexpr) { 6649 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors 6650 // are implicitly inline. 6651 NewFD->setImplicitlyInline(); 6652 6653 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to 6654 // be either constructors or to return a literal type. Therefore, 6655 // destructors cannot be declared constexpr. 6656 if (isa<CXXDestructorDecl>(NewFD)) 6657 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor); 6658 } 6659 6660 // If __module_private__ was specified, mark the function accordingly. 6661 if (D.getDeclSpec().isModulePrivateSpecified()) { 6662 if (isFunctionTemplateSpecialization) { 6663 SourceLocation ModulePrivateLoc 6664 = D.getDeclSpec().getModulePrivateSpecLoc(); 6665 Diag(ModulePrivateLoc, diag::err_module_private_specialization) 6666 << 0 6667 << FixItHint::CreateRemoval(ModulePrivateLoc); 6668 } else { 6669 NewFD->setModulePrivate(); 6670 if (FunctionTemplate) 6671 FunctionTemplate->setModulePrivate(); 6672 } 6673 } 6674 6675 if (isFriend) { 6676 if (FunctionTemplate) { 6677 FunctionTemplate->setObjectOfFriendDecl(); 6678 FunctionTemplate->setAccess(AS_public); 6679 } 6680 NewFD->setObjectOfFriendDecl(); 6681 NewFD->setAccess(AS_public); 6682 } 6683 6684 // If a function is defined as defaulted or deleted, mark it as such now. 6685 switch (D.getFunctionDefinitionKind()) { 6686 case FDK_Declaration: 6687 case FDK_Definition: 6688 break; 6689 6690 case FDK_Defaulted: 6691 NewFD->setDefaulted(); 6692 break; 6693 6694 case FDK_Deleted: 6695 NewFD->setDeletedAsWritten(); 6696 break; 6697 } 6698 6699 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && 6700 D.isFunctionDefinition()) { 6701 // C++ [class.mfct]p2: 6702 // A member function may be defined (8.4) in its class definition, in 6703 // which case it is an inline member function (7.1.2) 6704 NewFD->setImplicitlyInline(); 6705 } 6706 6707 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 6708 !CurContext->isRecord()) { 6709 // C++ [class.static]p1: 6710 // A data or function member of a class may be declared static 6711 // in a class definition, in which case it is a static member of 6712 // the class. 6713 6714 // Complain about the 'static' specifier if it's on an out-of-line 6715 // member function definition. 6716 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 6717 diag::err_static_out_of_line) 6718 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 6719 } 6720 6721 // C++11 [except.spec]p15: 6722 // A deallocation function with no exception-specification is treated 6723 // as if it were specified with noexcept(true). 6724 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>(); 6725 if ((Name.getCXXOverloadedOperator() == OO_Delete || 6726 Name.getCXXOverloadedOperator() == OO_Array_Delete) && 6727 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec()) { 6728 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); 6729 EPI.ExceptionSpecType = EST_BasicNoexcept; 6730 NewFD->setType(Context.getFunctionType(FPT->getResultType(), 6731 FPT->getArgTypes(), EPI)); 6732 } 6733 } 6734 6735 // Filter out previous declarations that don't match the scope. 6736 FilterLookupForScope(Previous, DC, S, shouldConsiderLinkage(NewFD), 6737 isExplicitSpecialization || 6738 isFunctionTemplateSpecialization); 6739 6740 // Handle GNU asm-label extension (encoded as an attribute). 6741 if (Expr *E = (Expr*) D.getAsmLabel()) { 6742 // The parser guarantees this is a string. 6743 StringLiteral *SE = cast<StringLiteral>(E); 6744 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 6745 SE->getString())); 6746 } else if (!ExtnameUndeclaredIdentifiers.empty()) { 6747 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I = 6748 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier()); 6749 if (I != ExtnameUndeclaredIdentifiers.end()) { 6750 NewFD->addAttr(I->second); 6751 ExtnameUndeclaredIdentifiers.erase(I); 6752 } 6753 } 6754 6755 // Copy the parameter declarations from the declarator D to the function 6756 // declaration NewFD, if they are available. First scavenge them into Params. 6757 SmallVector<ParmVarDecl*, 16> Params; 6758 if (D.isFunctionDeclarator()) { 6759 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 6760 6761 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 6762 // function that takes no arguments, not a function that takes a 6763 // single void argument. 6764 // We let through "const void" here because Sema::GetTypeForDeclarator 6765 // already checks for that case. 6766 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6767 FTI.ArgInfo[0].Param && 6768 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 6769 // Empty arg list, don't push any params. 6770 checkVoidParamDecl(cast<ParmVarDecl>(FTI.ArgInfo[0].Param)); 6771 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 6772 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 6773 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 6774 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 6775 Param->setDeclContext(NewFD); 6776 Params.push_back(Param); 6777 6778 if (Param->isInvalidDecl()) 6779 NewFD->setInvalidDecl(); 6780 } 6781 } 6782 6783 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 6784 // When we're declaring a function with a typedef, typeof, etc as in the 6785 // following example, we'll need to synthesize (unnamed) 6786 // parameters for use in the declaration. 6787 // 6788 // @code 6789 // typedef void fn(int); 6790 // fn f; 6791 // @endcode 6792 6793 // Synthesize a parameter for each argument type. 6794 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 6795 AE = FT->arg_type_end(); AI != AE; ++AI) { 6796 ParmVarDecl *Param = 6797 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 6798 Param->setScopeInfo(0, Params.size()); 6799 Params.push_back(Param); 6800 } 6801 } else { 6802 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 6803 "Should not need args for typedef of non-prototype fn"); 6804 } 6805 6806 // Finally, we know we have the right number of parameters, install them. 6807 NewFD->setParams(Params); 6808 6809 // Find all anonymous symbols defined during the declaration of this function 6810 // and add to NewFD. This lets us track decls such 'enum Y' in: 6811 // 6812 // void f(enum Y {AA} x) {} 6813 // 6814 // which would otherwise incorrectly end up in the translation unit scope. 6815 NewFD->setDeclsInPrototypeScope(DeclsInPrototypeScope); 6816 DeclsInPrototypeScope.clear(); 6817 6818 if (D.getDeclSpec().isNoreturnSpecified()) 6819 NewFD->addAttr( 6820 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(), 6821 Context)); 6822 6823 // Process the non-inheritable attributes on this declaration. 6824 ProcessDeclAttributes(S, NewFD, D, 6825 /*NonInheritable=*/true, /*Inheritable=*/false); 6826 6827 // Functions returning a variably modified type violate C99 6.7.5.2p2 6828 // because all functions have linkage. 6829 if (!NewFD->isInvalidDecl() && 6830 NewFD->getResultType()->isVariablyModifiedType()) { 6831 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 6832 NewFD->setInvalidDecl(); 6833 } 6834 6835 // Handle attributes. 6836 ProcessDeclAttributes(S, NewFD, D, 6837 /*NonInheritable=*/false, /*Inheritable=*/true); 6838 6839 QualType RetType = NewFD->getResultType(); 6840 const CXXRecordDecl *Ret = RetType->isRecordType() ? 6841 RetType->getAsCXXRecordDecl() : RetType->getPointeeCXXRecordDecl(); 6842 if (!NewFD->isInvalidDecl() && !NewFD->hasAttr<WarnUnusedResultAttr>() && 6843 Ret && Ret->hasAttr<WarnUnusedResultAttr>()) { 6844 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD); 6845 if (!(MD && MD->getCorrespondingMethodInClass(Ret, true))) { 6846 NewFD->addAttr(new (Context) WarnUnusedResultAttr(SourceRange(), 6847 Context)); 6848 } 6849 } 6850 6851 if (!getLangOpts().CPlusPlus) { 6852 // Perform semantic checking on the function declaration. 6853 bool isExplicitSpecialization=false; 6854 if (!NewFD->isInvalidDecl() && NewFD->isMain()) 6855 CheckMain(NewFD, D.getDeclSpec()); 6856 6857 if (!NewFD->isInvalidDecl()) 6858 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous, 6859 isExplicitSpecialization)); 6860 // Make graceful recovery from an invalid redeclaration. 6861 else if (!Previous.empty()) 6862 D.setRedeclaration(true); 6863 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() || 6864 Previous.getResultKind() != LookupResult::FoundOverloaded) && 6865 "previous declaration set still overloaded"); 6866 } else { 6867 // If the declarator is a template-id, translate the parser's template 6868 // argument list into our AST format. 6869 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 6870 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 6871 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 6872 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 6873 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 6874 TemplateId->NumArgs); 6875 translateTemplateArguments(TemplateArgsPtr, 6876 TemplateArgs); 6877 6878 HasExplicitTemplateArgs = true; 6879 6880 if (NewFD->isInvalidDecl()) { 6881 HasExplicitTemplateArgs = false; 6882 } else if (FunctionTemplate) { 6883 // Function template with explicit template arguments. 6884 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 6885 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 6886 6887 HasExplicitTemplateArgs = false; 6888 } else if (!isFunctionTemplateSpecialization && 6889 !D.getDeclSpec().isFriendSpecified()) { 6890 // We have encountered something that the user meant to be a 6891 // specialization (because it has explicitly-specified template 6892 // arguments) but that was not introduced with a "template<>" (or had 6893 // too few of them). 6894 // FIXME: Differentiate between attempts for explicit instantiations 6895 // (starting with "template") and the rest. 6896 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 6897 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 6898 << FixItHint::CreateInsertion( 6899 D.getDeclSpec().getLocStart(), 6900 "template<> "); 6901 isFunctionTemplateSpecialization = true; 6902 } else { 6903 // "friend void foo<>(int);" is an implicit specialization decl. 6904 isFunctionTemplateSpecialization = true; 6905 } 6906 } else if (isFriend && isFunctionTemplateSpecialization) { 6907 // This combination is only possible in a recovery case; the user 6908 // wrote something like: 6909 // template <> friend void foo(int); 6910 // which we're recovering from as if the user had written: 6911 // friend void foo<>(int); 6912 // Go ahead and fake up a template id. 6913 HasExplicitTemplateArgs = true; 6914 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 6915 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 6916 } 6917 6918 // If it's a friend (and only if it's a friend), it's possible 6919 // that either the specialized function type or the specialized 6920 // template is dependent, and therefore matching will fail. In 6921 // this case, don't check the specialization yet. 6922 bool InstantiationDependent = false; 6923 if (isFunctionTemplateSpecialization && isFriend && 6924 (NewFD->getType()->isDependentType() || DC->isDependentContext() || 6925 TemplateSpecializationType::anyDependentTemplateArguments( 6926 TemplateArgs.getArgumentArray(), TemplateArgs.size(), 6927 InstantiationDependent))) { 6928 assert(HasExplicitTemplateArgs && 6929 "friend function specialization without template args"); 6930 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 6931 Previous)) 6932 NewFD->setInvalidDecl(); 6933 } else if (isFunctionTemplateSpecialization) { 6934 if (CurContext->isDependentContext() && CurContext->isRecord() 6935 && !isFriend) { 6936 isDependentClassScopeExplicitSpecialization = true; 6937 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ? 6938 diag::ext_function_specialization_in_class : 6939 diag::err_function_specialization_in_class) 6940 << NewFD->getDeclName(); 6941 } else if (CheckFunctionTemplateSpecialization(NewFD, 6942 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 6943 Previous)) 6944 NewFD->setInvalidDecl(); 6945 6946 // C++ [dcl.stc]p1: 6947 // A storage-class-specifier shall not be specified in an explicit 6948 // specialization (14.7.3) 6949 FunctionTemplateSpecializationInfo *Info = 6950 NewFD->getTemplateSpecializationInfo(); 6951 if (Info && SC != SC_None) { 6952 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass()) 6953 Diag(NewFD->getLocation(), 6954 diag::err_explicit_specialization_inconsistent_storage_class) 6955 << SC 6956 << FixItHint::CreateRemoval( 6957 D.getDeclSpec().getStorageClassSpecLoc()); 6958 6959 else 6960 Diag(NewFD->getLocation(), 6961 diag::ext_explicit_specialization_storage_class) 6962 << FixItHint::CreateRemoval( 6963 D.getDeclSpec().getStorageClassSpecLoc()); 6964 } 6965 6966 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 6967 if (CheckMemberSpecialization(NewFD, Previous)) 6968 NewFD->setInvalidDecl(); 6969 } 6970 6971 // Perform semantic checking on the function declaration. 6972 if (!isDependentClassScopeExplicitSpecialization) { 6973 if (!NewFD->isInvalidDecl() && NewFD->isMain()) 6974 CheckMain(NewFD, D.getDeclSpec()); 6975 6976 if (NewFD->isInvalidDecl()) { 6977 // If this is a class member, mark the class invalid immediately. 6978 // This avoids some consistency errors later. 6979 if (CXXMethodDecl* methodDecl = dyn_cast<CXXMethodDecl>(NewFD)) 6980 methodDecl->getParent()->setInvalidDecl(); 6981 } else 6982 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous, 6983 isExplicitSpecialization)); 6984 } 6985 6986 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() || 6987 Previous.getResultKind() != LookupResult::FoundOverloaded) && 6988 "previous declaration set still overloaded"); 6989 6990 NamedDecl *PrincipalDecl = (FunctionTemplate 6991 ? cast<NamedDecl>(FunctionTemplate) 6992 : NewFD); 6993 6994 if (isFriend && D.isRedeclaration()) { 6995 AccessSpecifier Access = AS_public; 6996 if (!NewFD->isInvalidDecl()) 6997 Access = NewFD->getPreviousDecl()->getAccess(); 6998 6999 NewFD->setAccess(Access); 7000 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 7001 } 7002 7003 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 7004 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 7005 PrincipalDecl->setNonMemberOperator(); 7006 7007 // If we have a function template, check the template parameter 7008 // list. This will check and merge default template arguments. 7009 if (FunctionTemplate) { 7010 FunctionTemplateDecl *PrevTemplate = 7011 FunctionTemplate->getPreviousDecl(); 7012 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 7013 PrevTemplate ? PrevTemplate->getTemplateParameters() : 0, 7014 D.getDeclSpec().isFriendSpecified() 7015 ? (D.isFunctionDefinition() 7016 ? TPC_FriendFunctionTemplateDefinition 7017 : TPC_FriendFunctionTemplate) 7018 : (D.getCXXScopeSpec().isSet() && 7019 DC && DC->isRecord() && 7020 DC->isDependentContext()) 7021 ? TPC_ClassTemplateMember 7022 : TPC_FunctionTemplate); 7023 } 7024 7025 if (NewFD->isInvalidDecl()) { 7026 // Ignore all the rest of this. 7027 } else if (!D.isRedeclaration()) { 7028 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists, 7029 AddToScope }; 7030 // Fake up an access specifier if it's supposed to be a class member. 7031 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 7032 NewFD->setAccess(