SemaDecl.cpp revision fe2695eec167b28578825576863228f86b392f24
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 "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "TypeLocBuilder.h" 21#include "clang/AST/APValue.h" 22#include "clang/AST/ASTConsumer.h" 23#include "clang/AST/ASTContext.h" 24#include "clang/AST/CXXInheritance.h" 25#include "clang/AST/DeclCXX.h" 26#include "clang/AST/DeclObjC.h" 27#include "clang/AST/DeclTemplate.h" 28#include "clang/AST/EvaluatedExprVisitor.h" 29#include "clang/AST/ExprCXX.h" 30#include "clang/AST/StmtCXX.h" 31#include "clang/AST/CharUnits.h" 32#include "clang/Sema/DeclSpec.h" 33#include "clang/Sema/ParsedTemplate.h" 34#include "clang/Parse/ParseDiagnostic.h" 35#include "clang/Basic/PartialDiagnostic.h" 36#include "clang/Basic/SourceManager.h" 37#include "clang/Basic/TargetInfo.h" 38// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 39#include "clang/Lex/Preprocessor.h" 40#include "clang/Lex/HeaderSearch.h" 41#include "llvm/ADT/Triple.h" 42#include <algorithm> 43#include <cstring> 44#include <functional> 45using namespace clang; 46using namespace sema; 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, bool HasTrailingDot, 66 ParsedType ObjectTypePtr, 67 bool WantNontrivialTypeSourceInfo) { 68 // Determine where we will perform name lookup. 69 DeclContext *LookupCtx = 0; 70 if (ObjectTypePtr) { 71 QualType ObjectType = ObjectTypePtr.get(); 72 if (ObjectType->isRecordType()) 73 LookupCtx = computeDeclContext(ObjectType); 74 } else if (SS && SS->isNotEmpty()) { 75 LookupCtx = computeDeclContext(*SS, false); 76 77 if (!LookupCtx) { 78 if (isDependentScopeSpecifier(*SS)) { 79 // C++ [temp.res]p3: 80 // A qualified-id that refers to a type and in which the 81 // nested-name-specifier depends on a template-parameter (14.6.2) 82 // shall be prefixed by the keyword typename to indicate that the 83 // qualified-id denotes a type, forming an 84 // elaborated-type-specifier (7.1.5.3). 85 // 86 // We therefore do not perform any name lookup if the result would 87 // refer to a member of an unknown specialization. 88 if (!isClassName) 89 return ParsedType(); 90 91 // We know from the grammar that this name refers to a type, 92 // so build a dependent node to describe the type. 93 if (WantNontrivialTypeSourceInfo) 94 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); 95 96 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); 97 QualType T = 98 CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, 99 II, NameLoc); 100 101 return ParsedType::make(T); 102 } 103 104 return ParsedType(); 105 } 106 107 if (!LookupCtx->isDependentContext() && 108 RequireCompleteDeclContext(*SS, LookupCtx)) 109 return ParsedType(); 110 } 111 112 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 113 // lookup for class-names. 114 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 115 LookupOrdinaryName; 116 LookupResult Result(*this, &II, NameLoc, Kind); 117 if (LookupCtx) { 118 // Perform "qualified" name lookup into the declaration context we 119 // computed, which is either the type of the base of a member access 120 // expression or the declaration context associated with a prior 121 // nested-name-specifier. 122 LookupQualifiedName(Result, LookupCtx); 123 124 if (ObjectTypePtr && Result.empty()) { 125 // C++ [basic.lookup.classref]p3: 126 // If the unqualified-id is ~type-name, the type-name is looked up 127 // in the context of the entire postfix-expression. If the type T of 128 // the object expression is of a class type C, the type-name is also 129 // looked up in the scope of class C. At least one of the lookups shall 130 // find a name that refers to (possibly cv-qualified) T. 131 LookupName(Result, S); 132 } 133 } else { 134 // Perform unqualified name lookup. 135 LookupName(Result, S); 136 } 137 138 NamedDecl *IIDecl = 0; 139 switch (Result.getResultKind()) { 140 case LookupResult::NotFound: 141 case LookupResult::NotFoundInCurrentInstantiation: 142 case LookupResult::FoundOverloaded: 143 case LookupResult::FoundUnresolvedValue: 144 Result.suppressDiagnostics(); 145 return ParsedType(); 146 147 case LookupResult::Ambiguous: 148 // Recover from type-hiding ambiguities by hiding the type. We'll 149 // do the lookup again when looking for an object, and we can 150 // diagnose the error then. If we don't do this, then the error 151 // about hiding the type will be immediately followed by an error 152 // that only makes sense if the identifier was treated like a type. 153 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 154 Result.suppressDiagnostics(); 155 return ParsedType(); 156 } 157 158 // Look to see if we have a type anywhere in the list of results. 159 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 160 Res != ResEnd; ++Res) { 161 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 162 if (!IIDecl || 163 (*Res)->getLocation().getRawEncoding() < 164 IIDecl->getLocation().getRawEncoding()) 165 IIDecl = *Res; 166 } 167 } 168 169 if (!IIDecl) { 170 // None of the entities we found is a type, so there is no way 171 // to even assume that the result is a type. In this case, don't 172 // complain about the ambiguity. The parser will either try to 173 // perform this lookup again (e.g., as an object name), which 174 // will produce the ambiguity, or will complain that it expected 175 // a type name. 176 Result.suppressDiagnostics(); 177 return ParsedType(); 178 } 179 180 // We found a type within the ambiguous lookup; diagnose the 181 // ambiguity and then return that type. This might be the right 182 // answer, or it might not be, but it suppresses any attempt to 183 // perform the name lookup again. 184 break; 185 186 case LookupResult::Found: 187 IIDecl = Result.getFoundDecl(); 188 break; 189 } 190 191 assert(IIDecl && "Didn't find decl"); 192 193 QualType T; 194 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 195 DiagnoseUseOfDecl(IIDecl, NameLoc); 196 197 if (T.isNull()) 198 T = Context.getTypeDeclType(TD); 199 200 if (SS && SS->isNotEmpty()) { 201 if (WantNontrivialTypeSourceInfo) { 202 // Construct a type with type-source information. 203 TypeLocBuilder Builder; 204 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 205 206 T = getElaboratedType(ETK_None, *SS, T); 207 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 208 ElabTL.setKeywordLoc(SourceLocation()); 209 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); 210 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 211 } else { 212 T = getElaboratedType(ETK_None, *SS, T); 213 } 214 } 215 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 216 (void)DiagnoseUseOfDecl(IDecl, NameLoc); 217 if (!HasTrailingDot) 218 T = Context.getObjCInterfaceType(IDecl); 219 } 220 221 if (T.isNull()) { 222 // If it's not plausibly a type, suppress diagnostics. 223 Result.suppressDiagnostics(); 224 return ParsedType(); 225 } 226 return ParsedType::make(T); 227} 228 229/// isTagName() - This method is called *for error recovery purposes only* 230/// to determine if the specified name is a valid tag name ("struct foo"). If 231/// so, this returns the TST for the tag corresponding to it (TST_enum, 232/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 233/// where the user forgot to specify the tag. 234DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 235 // Do a tag name lookup in this scope. 236 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 237 LookupName(R, S, false); 238 R.suppressDiagnostics(); 239 if (R.getResultKind() == LookupResult::Found) 240 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 241 switch (TD->getTagKind()) { 242 default: return DeclSpec::TST_unspecified; 243 case TTK_Struct: return DeclSpec::TST_struct; 244 case TTK_Union: return DeclSpec::TST_union; 245 case TTK_Class: return DeclSpec::TST_class; 246 case TTK_Enum: return DeclSpec::TST_enum; 247 } 248 } 249 250 return DeclSpec::TST_unspecified; 251} 252 253/// isMicrosoftMissingTypename - In Microsoft mode, within class scope, 254/// if a CXXScopeSpec's type is equal to the type of one of the base classes 255/// then downgrade the missing typename error to a warning. 256/// This is needed for MSVC compatibility; Example: 257/// @code 258/// template<class T> class A { 259/// public: 260/// typedef int TYPE; 261/// }; 262/// template<class T> class B : public A<T> { 263/// public: 264/// A<T>::TYPE a; // no typename required because A<T> is a base class. 265/// }; 266/// @endcode 267bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS) { 268 if (CurContext->isRecord()) { 269 const Type *Ty = SS->getScopeRep()->getAsType(); 270 271 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext); 272 for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), 273 BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) 274 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base->getType())) 275 return true; 276 } 277 return false; 278} 279 280bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 281 SourceLocation IILoc, 282 Scope *S, 283 CXXScopeSpec *SS, 284 ParsedType &SuggestedType) { 285 // We don't have anything to suggest (yet). 286 SuggestedType = ParsedType(); 287 288 // There may have been a typo in the name of the type. Look up typo 289 // results, in case we have something that we can suggest. 290 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 291 NotForRedeclaration); 292 293 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 294 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 295 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 296 !Result->isInvalidDecl()) { 297 // We found a similarly-named type or interface; suggest that. 298 if (!SS || !SS->isSet()) 299 Diag(IILoc, diag::err_unknown_typename_suggest) 300 << &II << Lookup.getLookupName() 301 << FixItHint::CreateReplacement(SourceRange(IILoc), 302 Result->getNameAsString()); 303 else if (DeclContext *DC = computeDeclContext(*SS, false)) 304 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 305 << &II << DC << Lookup.getLookupName() << SS->getRange() 306 << FixItHint::CreateReplacement(SourceRange(IILoc), 307 Result->getNameAsString()); 308 else 309 llvm_unreachable("could not have corrected a typo here"); 310 311 Diag(Result->getLocation(), diag::note_previous_decl) 312 << Result->getDeclName(); 313 314 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, 315 false, false, ParsedType(), 316 /*NonTrivialTypeSourceInfo=*/true); 317 return true; 318 } 319 } else if (Lookup.empty()) { 320 // We corrected to a keyword. 321 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 322 Diag(IILoc, diag::err_unknown_typename_suggest) 323 << &II << Corrected; 324 return true; 325 } 326 } 327 328 if (getLangOptions().CPlusPlus) { 329 // See if II is a class template that the user forgot to pass arguments to. 330 UnqualifiedId Name; 331 Name.setIdentifier(&II, IILoc); 332 CXXScopeSpec EmptySS; 333 TemplateTy TemplateResult; 334 bool MemberOfUnknownSpecialization; 335 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 336 Name, ParsedType(), true, TemplateResult, 337 MemberOfUnknownSpecialization) == TNK_Type_template) { 338 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 339 Diag(IILoc, diag::err_template_missing_args) << TplName; 340 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 341 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 342 << TplDecl->getTemplateParameters()->getSourceRange(); 343 } 344 return true; 345 } 346 } 347 348 // FIXME: Should we move the logic that tries to recover from a missing tag 349 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 350 351 if (!SS || (!SS->isSet() && !SS->isInvalid())) 352 Diag(IILoc, diag::err_unknown_typename) << &II; 353 else if (DeclContext *DC = computeDeclContext(*SS, false)) 354 Diag(IILoc, diag::err_typename_nested_not_found) 355 << &II << DC << SS->getRange(); 356 else if (isDependentScopeSpecifier(*SS)) { 357 unsigned DiagID = diag::err_typename_missing; 358 if (getLangOptions().Microsoft && isMicrosoftMissingTypename(SS)) 359 DiagID = diag::warn_typename_missing; 360 361 Diag(SS->getRange().getBegin(), DiagID) 362 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 363 << SourceRange(SS->getRange().getBegin(), IILoc) 364 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 365 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 366 } else { 367 assert(SS && SS->isInvalid() && 368 "Invalid scope specifier has already been diagnosed"); 369 } 370 371 return true; 372} 373 374/// \brief Determine whether the given result set contains either a type name 375/// or 376static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) { 377 bool CheckTemplate = R.getSema().getLangOptions().CPlusPlus && 378 NextToken.is(tok::less); 379 380 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) { 381 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I)) 382 return true; 383 384 if (CheckTemplate && isa<TemplateDecl>(*I)) 385 return true; 386 } 387 388 return false; 389} 390 391Sema::NameClassification Sema::ClassifyName(Scope *S, 392 CXXScopeSpec &SS, 393 IdentifierInfo *&Name, 394 SourceLocation NameLoc, 395 const Token &NextToken) { 396 DeclarationNameInfo NameInfo(Name, NameLoc); 397 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 398 399 if (NextToken.is(tok::coloncolon)) { 400 BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(), 401 QualType(), false, SS, 0, false); 402 403 } 404 405 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName); 406 LookupParsedName(Result, S, &SS, !CurMethod); 407 408 // Perform lookup for Objective-C instance variables (including automatically 409 // synthesized instance variables), if we're in an Objective-C method. 410 // FIXME: This lookup really, really needs to be folded in to the normal 411 // unqualified lookup mechanism. 412 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) { 413 ExprResult E = LookupInObjCMethod(Result, S, Name, true); 414 if (E.get() || E.isInvalid()) 415 return E; 416 417 // Synthesize ivars lazily. 418 if (getLangOptions().ObjCDefaultSynthProperties && 419 getLangOptions().ObjCNonFragileABI2) { 420 if (SynthesizeProvisionalIvar(Result, Name, NameLoc)) { 421 if (const ObjCPropertyDecl *Property = 422 canSynthesizeProvisionalIvar(Name)) { 423 Diag(NameLoc, diag::warn_synthesized_ivar_access) << Name; 424 Diag(Property->getLocation(), diag::note_property_declare); 425 } 426 427 // FIXME: This is strange. Shouldn't we just take the ivar returned 428 // from SynthesizeProvisionalIvar and continue with that? 429 E = LookupInObjCMethod(Result, S, Name, true); 430 if (E.get() || E.isInvalid()) 431 return E; 432 } 433 } 434 } 435 436 bool SecondTry = false; 437 bool IsFilteredTemplateName = false; 438 439Corrected: 440 switch (Result.getResultKind()) { 441 case LookupResult::NotFound: 442 // If an unqualified-id is followed by a '(', then we have a function 443 // call. 444 if (!SS.isSet() && NextToken.is(tok::l_paren)) { 445 // In C++, this is an ADL-only call. 446 // FIXME: Reference? 447 if (getLangOptions().CPlusPlus) 448 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true); 449 450 // C90 6.3.2.2: 451 // If the expression that precedes the parenthesized argument list in a 452 // function call consists solely of an identifier, and if no 453 // declaration is visible for this identifier, the identifier is 454 // implicitly declared exactly as if, in the innermost block containing 455 // the function call, the declaration 456 // 457 // extern int identifier (); 458 // 459 // appeared. 460 // 461 // We also allow this in C99 as an extension. 462 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) { 463 Result.addDecl(D); 464 Result.resolveKind(); 465 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false); 466 } 467 } 468 469 // In C, we first see whether there is a tag type by the same name, in 470 // which case it's likely that the user just forget to write "enum", 471 // "struct", or "union". 472 if (!getLangOptions().CPlusPlus && !SecondTry) { 473 Result.clear(LookupTagName); 474 LookupParsedName(Result, S, &SS); 475 if (TagDecl *Tag = Result.getAsSingle<TagDecl>()) { 476 const char *TagName = 0; 477 const char *FixItTagName = 0; 478 switch (Tag->getTagKind()) { 479 case TTK_Class: 480 TagName = "class"; 481 FixItTagName = "class "; 482 break; 483 484 case TTK_Enum: 485 TagName = "enum"; 486 FixItTagName = "enum "; 487 break; 488 489 case TTK_Struct: 490 TagName = "struct"; 491 FixItTagName = "struct "; 492 break; 493 494 case TTK_Union: 495 TagName = "union"; 496 FixItTagName = "union "; 497 break; 498 } 499 500 Diag(NameLoc, diag::err_use_of_tag_name_without_tag) 501 << Name << TagName << getLangOptions().CPlusPlus 502 << FixItHint::CreateInsertion(NameLoc, FixItTagName); 503 break; 504 } 505 506 Result.clear(LookupOrdinaryName); 507 } 508 509 // Perform typo correction to determine if there is another name that is 510 // close to this name. 511 if (!SecondTry) { 512 if (DeclarationName Corrected = CorrectTypo(Result, S, &SS)) { 513 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest; 514 unsigned QualifiedDiag = diag::err_no_member_suggest; 515 516 NamedDecl *FirstDecl = Result.empty()? 0 : *Result.begin(); 517 NamedDecl *UnderlyingFirstDecl 518 = FirstDecl? FirstDecl->getUnderlyingDecl() : 0; 519 if (getLangOptions().CPlusPlus && NextToken.is(tok::less) && 520 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) { 521 UnqualifiedDiag = diag::err_no_template_suggest; 522 QualifiedDiag = diag::err_no_member_template_suggest; 523 } else if (UnderlyingFirstDecl && 524 (isa<TypeDecl>(UnderlyingFirstDecl) || 525 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) || 526 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) { 527 UnqualifiedDiag = diag::err_unknown_typename_suggest; 528 QualifiedDiag = diag::err_unknown_nested_typename_suggest; 529 } 530 531 if (SS.isEmpty()) 532 Diag(NameLoc, UnqualifiedDiag) 533 << Name << Corrected 534 << FixItHint::CreateReplacement(NameLoc, Corrected.getAsString()); 535 else 536 Diag(NameLoc, QualifiedDiag) 537 << Name << computeDeclContext(SS, false) << Corrected 538 << SS.getRange() 539 << FixItHint::CreateReplacement(NameLoc, Corrected.getAsString()); 540 541 // Update the name, so that the caller has the new name. 542 Name = Corrected.getAsIdentifierInfo(); 543 544 // Typo correction corrected to a keyword. 545 if (Result.empty()) 546 return Corrected.getAsIdentifierInfo(); 547 548 Diag(FirstDecl->getLocation(), diag::note_previous_decl) 549 << FirstDecl->getDeclName(); 550 551 // If we found an Objective-C instance variable, let 552 // LookupInObjCMethod build the appropriate expression to 553 // reference the ivar. 554 // FIXME: This is a gross hack. 555 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) { 556 Result.clear(); 557 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier())); 558 return move(E); 559 } 560 561 goto Corrected; 562 } 563 } 564 565 // We failed to correct; just fall through and let the parser deal with it. 566 Result.suppressDiagnostics(); 567 return NameClassification::Unknown(); 568 569 case LookupResult::NotFoundInCurrentInstantiation: 570 // We performed name lookup into the current instantiation, and there were 571 // dependent bases, so we treat this result the same way as any other 572 // dependent nested-name-specifier. 573 574 // C++ [temp.res]p2: 575 // A name used in a template declaration or definition and that is 576 // dependent on a template-parameter is assumed not to name a type 577 // unless the applicable name lookup finds a type name or the name is 578 // qualified by the keyword typename. 579 // 580 // FIXME: If the next token is '<', we might want to ask the parser to 581 // perform some heroics to see if we actually have a 582 // template-argument-list, which would indicate a missing 'template' 583 // keyword here. 584 return BuildDependentDeclRefExpr(SS, NameInfo, /*TemplateArgs=*/0); 585 586 case LookupResult::Found: 587 case LookupResult::FoundOverloaded: 588 case LookupResult::FoundUnresolvedValue: 589 break; 590 591 case LookupResult::Ambiguous: 592 if (getLangOptions().CPlusPlus && NextToken.is(tok::less) && 593 hasAnyAcceptableTemplateNames(Result)) { 594 // C++ [temp.local]p3: 595 // A lookup that finds an injected-class-name (10.2) can result in an 596 // ambiguity in certain cases (for example, if it is found in more than 597 // one base class). If all of the injected-class-names that are found 598 // refer to specializations of the same class template, and if the name 599 // is followed by a template-argument-list, the reference refers to the 600 // class template itself and not a specialization thereof, and is not 601 // ambiguous. 602 // 603 // This filtering can make an ambiguous result into an unambiguous one, 604 // so try again after filtering out template names. 605 FilterAcceptableTemplateNames(Result); 606 if (!Result.isAmbiguous()) { 607 IsFilteredTemplateName = true; 608 break; 609 } 610 } 611 612 // Diagnose the ambiguity and return an error. 613 return NameClassification::Error(); 614 } 615 616 if (getLangOptions().CPlusPlus && NextToken.is(tok::less) && 617 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) { 618 // C++ [temp.names]p3: 619 // After name lookup (3.4) finds that a name is a template-name or that 620 // an operator-function-id or a literal- operator-id refers to a set of 621 // overloaded functions any member of which is a function template if 622 // this is followed by a <, the < is always taken as the delimiter of a 623 // template-argument-list and never as the less-than operator. 624 if (!IsFilteredTemplateName) 625 FilterAcceptableTemplateNames(Result); 626 627 if (!Result.empty()) { 628 bool IsFunctionTemplate; 629 TemplateName Template; 630 if (Result.end() - Result.begin() > 1) { 631 IsFunctionTemplate = true; 632 Template = Context.getOverloadedTemplateName(Result.begin(), 633 Result.end()); 634 } else { 635 TemplateDecl *TD 636 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl()); 637 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD); 638 639 if (SS.isSet() && !SS.isInvalid()) 640 Template = Context.getQualifiedTemplateName(SS.getScopeRep(), 641 /*TemplateKeyword=*/false, 642 TD); 643 else 644 Template = TemplateName(TD); 645 } 646 647 if (IsFunctionTemplate) { 648 // Function templates always go through overload resolution, at which 649 // point we'll perform the various checks (e.g., accessibility) we need 650 // to based on which function we selected. 651 Result.suppressDiagnostics(); 652 653 return NameClassification::FunctionTemplate(Template); 654 } 655 656 return NameClassification::TypeTemplate(Template); 657 } 658 } 659 660 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl(); 661 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) { 662 DiagnoseUseOfDecl(Type, NameLoc); 663 QualType T = Context.getTypeDeclType(Type); 664 return ParsedType::make(T); 665 } 666 667 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl); 668 if (!Class) { 669 // FIXME: It's unfortunate that we don't have a Type node for handling this. 670 if (ObjCCompatibleAliasDecl *Alias 671 = dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl)) 672 Class = Alias->getClassInterface(); 673 } 674 675 if (Class) { 676 DiagnoseUseOfDecl(Class, NameLoc); 677 678 if (NextToken.is(tok::period)) { 679 // Interface. <something> is parsed as a property reference expression. 680 // Just return "unknown" as a fall-through for now. 681 Result.suppressDiagnostics(); 682 return NameClassification::Unknown(); 683 } 684 685 QualType T = Context.getObjCInterfaceType(Class); 686 return ParsedType::make(T); 687 } 688 689 if (!Result.empty() && (*Result.begin())->isCXXClassMember()) 690 return BuildPossibleImplicitMemberExpr(SS, Result, 0); 691 692 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren)); 693 return BuildDeclarationNameExpr(SS, Result, ADL); 694} 695 696// Determines the context to return to after temporarily entering a 697// context. This depends in an unnecessarily complicated way on the 698// exact ordering of callbacks from the parser. 699DeclContext *Sema::getContainingDC(DeclContext *DC) { 700 701 // Functions defined inline within classes aren't parsed until we've 702 // finished parsing the top-level class, so the top-level class is 703 // the context we'll need to return to. 704 if (isa<FunctionDecl>(DC)) { 705 DC = DC->getLexicalParent(); 706 707 // A function not defined within a class will always return to its 708 // lexical context. 709 if (!isa<CXXRecordDecl>(DC)) 710 return DC; 711 712 // A C++ inline method/friend is parsed *after* the topmost class 713 // it was declared in is fully parsed ("complete"); the topmost 714 // class is the context we need to return to. 715 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 716 DC = RD; 717 718 // Return the declaration context of the topmost class the inline method is 719 // declared in. 720 return DC; 721 } 722 723 // ObjCMethodDecls are parsed (for some reason) outside the context 724 // of the class. 725 if (isa<ObjCMethodDecl>(DC)) 726 return DC->getLexicalParent()->getLexicalParent(); 727 728 return DC->getLexicalParent(); 729} 730 731void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 732 assert(getContainingDC(DC) == CurContext && 733 "The next DeclContext should be lexically contained in the current one."); 734 CurContext = DC; 735 S->setEntity(DC); 736} 737 738void Sema::PopDeclContext() { 739 assert(CurContext && "DeclContext imbalance!"); 740 741 CurContext = getContainingDC(CurContext); 742 assert(CurContext && "Popped translation unit!"); 743} 744 745/// EnterDeclaratorContext - Used when we must lookup names in the context 746/// of a declarator's nested name specifier. 747/// 748void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 749 // C++0x [basic.lookup.unqual]p13: 750 // A name used in the definition of a static data member of class 751 // X (after the qualified-id of the static member) is looked up as 752 // if the name was used in a member function of X. 753 // C++0x [basic.lookup.unqual]p14: 754 // If a variable member of a namespace is defined outside of the 755 // scope of its namespace then any name used in the definition of 756 // the variable member (after the declarator-id) is looked up as 757 // if the definition of the variable member occurred in its 758 // namespace. 759 // Both of these imply that we should push a scope whose context 760 // is the semantic context of the declaration. We can't use 761 // PushDeclContext here because that context is not necessarily 762 // lexically contained in the current context. Fortunately, 763 // the containing scope should have the appropriate information. 764 765 assert(!S->getEntity() && "scope already has entity"); 766 767#ifndef NDEBUG 768 Scope *Ancestor = S->getParent(); 769 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 770 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 771#endif 772 773 CurContext = DC; 774 S->setEntity(DC); 775} 776 777void Sema::ExitDeclaratorContext(Scope *S) { 778 assert(S->getEntity() == CurContext && "Context imbalance!"); 779 780 // Switch back to the lexical context. The safety of this is 781 // enforced by an assert in EnterDeclaratorContext. 782 Scope *Ancestor = S->getParent(); 783 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 784 CurContext = (DeclContext*) Ancestor->getEntity(); 785 786 // We don't need to do anything with the scope, which is going to 787 // disappear. 788} 789 790/// \brief Determine whether we allow overloading of the function 791/// PrevDecl with another declaration. 792/// 793/// This routine determines whether overloading is possible, not 794/// whether some new function is actually an overload. It will return 795/// true in C++ (where we can always provide overloads) or, as an 796/// extension, in C when the previous function is already an 797/// overloaded function declaration or has the "overloadable" 798/// attribute. 799static bool AllowOverloadingOfFunction(LookupResult &Previous, 800 ASTContext &Context) { 801 if (Context.getLangOptions().CPlusPlus) 802 return true; 803 804 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 805 return true; 806 807 return (Previous.getResultKind() == LookupResult::Found 808 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 809} 810 811/// Add this decl to the scope shadowed decl chains. 812void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 813 // Move up the scope chain until we find the nearest enclosing 814 // non-transparent context. The declaration will be introduced into this 815 // scope. 816 while (S->getEntity() && 817 ((DeclContext *)S->getEntity())->isTransparentContext()) 818 S = S->getParent(); 819 820 // Add scoped declarations into their context, so that they can be 821 // found later. Declarations without a context won't be inserted 822 // into any context. 823 if (AddToContext) 824 CurContext->addDecl(D); 825 826 // Out-of-line definitions shouldn't be pushed into scope in C++. 827 // Out-of-line variable and function definitions shouldn't even in C. 828 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 829 D->isOutOfLine()) 830 return; 831 832 // Template instantiations should also not be pushed into scope. 833 if (isa<FunctionDecl>(D) && 834 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 835 return; 836 837 // If this replaces anything in the current scope, 838 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 839 IEnd = IdResolver.end(); 840 for (; I != IEnd; ++I) { 841 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 842 S->RemoveDecl(*I); 843 IdResolver.RemoveDecl(*I); 844 845 // Should only need to replace one decl. 846 break; 847 } 848 } 849 850 S->AddDecl(D); 851 852 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { 853 // Implicitly-generated labels may end up getting generated in an order that 854 // isn't strictly lexical, which breaks name lookup. Be careful to insert 855 // the label at the appropriate place in the identifier chain. 856 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { 857 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext(); 858 if (IDC == CurContext) { 859 if (!S->isDeclScope(*I)) 860 continue; 861 } else if (IDC->Encloses(CurContext)) 862 break; 863 } 864 865 IdResolver.InsertDeclAfter(I, D); 866 } else { 867 IdResolver.AddDecl(D); 868 } 869} 870 871bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S, 872 bool ExplicitInstantiationOrSpecialization) { 873 return IdResolver.isDeclInScope(D, Ctx, Context, S, 874 ExplicitInstantiationOrSpecialization); 875} 876 877Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 878 DeclContext *TargetDC = DC->getPrimaryContext(); 879 do { 880 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 881 if (ScopeDC->getPrimaryContext() == TargetDC) 882 return S; 883 } while ((S = S->getParent())); 884 885 return 0; 886} 887 888static bool isOutOfScopePreviousDeclaration(NamedDecl *, 889 DeclContext*, 890 ASTContext&); 891 892/// Filters out lookup results that don't fall within the given scope 893/// as determined by isDeclInScope. 894void Sema::FilterLookupForScope(LookupResult &R, 895 DeclContext *Ctx, Scope *S, 896 bool ConsiderLinkage, 897 bool ExplicitInstantiationOrSpecialization) { 898 LookupResult::Filter F = R.makeFilter(); 899 while (F.hasNext()) { 900 NamedDecl *D = F.next(); 901 902 if (isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization)) 903 continue; 904 905 if (ConsiderLinkage && 906 isOutOfScopePreviousDeclaration(D, Ctx, Context)) 907 continue; 908 909 F.erase(); 910 } 911 912 F.done(); 913} 914 915static bool isUsingDecl(NamedDecl *D) { 916 return isa<UsingShadowDecl>(D) || 917 isa<UnresolvedUsingTypenameDecl>(D) || 918 isa<UnresolvedUsingValueDecl>(D); 919} 920 921/// Removes using shadow declarations from the lookup results. 922static void RemoveUsingDecls(LookupResult &R) { 923 LookupResult::Filter F = R.makeFilter(); 924 while (F.hasNext()) 925 if (isUsingDecl(F.next())) 926 F.erase(); 927 928 F.done(); 929} 930 931/// \brief Check for this common pattern: 932/// @code 933/// class S { 934/// S(const S&); // DO NOT IMPLEMENT 935/// void operator=(const S&); // DO NOT IMPLEMENT 936/// }; 937/// @endcode 938static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 939 // FIXME: Should check for private access too but access is set after we get 940 // the decl here. 941 if (D->isThisDeclarationADefinition()) 942 return false; 943 944 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 945 return CD->isCopyConstructor(); 946 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 947 return Method->isCopyAssignmentOperator(); 948 return false; 949} 950 951bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 952 assert(D); 953 954 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 955 return false; 956 957 // Ignore class templates. 958 if (D->getDeclContext()->isDependentContext() || 959 D->getLexicalDeclContext()->isDependentContext()) 960 return false; 961 962 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 963 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 964 return false; 965 966 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 967 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 968 return false; 969 } else { 970 // 'static inline' functions are used in headers; don't warn. 971 if (FD->getStorageClass() == SC_Static && 972 FD->isInlineSpecified()) 973 return false; 974 } 975 976 if (FD->isThisDeclarationADefinition() && 977 Context.DeclMustBeEmitted(FD)) 978 return false; 979 980 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 981 if (!VD->isFileVarDecl() || 982 VD->getType().isConstant(Context) || 983 Context.DeclMustBeEmitted(VD)) 984 return false; 985 986 if (VD->isStaticDataMember() && 987 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 988 return false; 989 990 } else { 991 return false; 992 } 993 994 // Only warn for unused decls internal to the translation unit. 995 if (D->getLinkage() == ExternalLinkage) 996 return false; 997 998 return true; 999} 1000 1001void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 1002 if (!D) 1003 return; 1004 1005 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1006 const FunctionDecl *First = FD->getFirstDeclaration(); 1007 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 1008 return; // First should already be in the vector. 1009 } 1010 1011 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1012 const VarDecl *First = VD->getFirstDeclaration(); 1013 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 1014 return; // First should already be in the vector. 1015 } 1016 1017 if (ShouldWarnIfUnusedFileScopedDecl(D)) 1018 UnusedFileScopedDecls.push_back(D); 1019 } 1020 1021static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 1022 if (D->isInvalidDecl()) 1023 return false; 1024 1025 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 1026 return false; 1027 1028 if (isa<LabelDecl>(D)) 1029 return true; 1030 1031 // White-list anything that isn't a local variable. 1032 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 1033 !D->getDeclContext()->isFunctionOrMethod()) 1034 return false; 1035 1036 // Types of valid local variables should be complete, so this should succeed. 1037 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 1038 1039 // White-list anything with an __attribute__((unused)) type. 1040 QualType Ty = VD->getType(); 1041 1042 // Only look at the outermost level of typedef. 1043 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 1044 if (TT->getDecl()->hasAttr<UnusedAttr>()) 1045 return false; 1046 } 1047 1048 // If we failed to complete the type for some reason, or if the type is 1049 // dependent, don't diagnose the variable. 1050 if (Ty->isIncompleteType() || Ty->isDependentType()) 1051 return false; 1052 1053 if (const TagType *TT = Ty->getAs<TagType>()) { 1054 const TagDecl *Tag = TT->getDecl(); 1055 if (Tag->hasAttr<UnusedAttr>()) 1056 return false; 1057 1058 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 1059 // FIXME: Checking for the presence of a user-declared constructor 1060 // isn't completely accurate; we'd prefer to check that the initializer 1061 // has no side effects. 1062 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 1063 return false; 1064 } 1065 } 1066 1067 // TODO: __attribute__((unused)) templates? 1068 } 1069 1070 return true; 1071} 1072 1073/// DiagnoseUnusedDecl - Emit warnings about declarations that are not used 1074/// unless they are marked attr(unused). 1075void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 1076 if (!ShouldDiagnoseUnusedDecl(D)) 1077 return; 1078 1079 unsigned DiagID; 1080 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 1081 DiagID = diag::warn_unused_exception_param; 1082 else if (isa<LabelDecl>(D)) 1083 DiagID = diag::warn_unused_label; 1084 else 1085 DiagID = diag::warn_unused_variable; 1086 1087 Diag(D->getLocation(), DiagID) << D->getDeclName(); 1088} 1089 1090static void CheckPoppedLabel(LabelDecl *L, Sema &S) { 1091 // Verify that we have no forward references left. If so, there was a goto 1092 // or address of a label taken, but no definition of it. Label fwd 1093 // definitions are indicated with a null substmt. 1094 if (L->getStmt() == 0) 1095 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); 1096} 1097 1098void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 1099 if (S->decl_empty()) return; 1100 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 1101 "Scope shouldn't contain decls!"); 1102 1103 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 1104 I != E; ++I) { 1105 Decl *TmpD = (*I); 1106 assert(TmpD && "This decl didn't get pushed??"); 1107 1108 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 1109 NamedDecl *D = cast<NamedDecl>(TmpD); 1110 1111 if (!D->getDeclName()) continue; 1112 1113 // Diagnose unused variables in this scope. 1114 if (!S->hasErrorOccurred()) 1115 DiagnoseUnusedDecl(D); 1116 1117 // If this was a forward reference to a label, verify it was defined. 1118 if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) 1119 CheckPoppedLabel(LD, *this); 1120 1121 // Remove this name from our lexical scope. 1122 IdResolver.RemoveDecl(D); 1123 } 1124} 1125 1126/// \brief Look for an Objective-C class in the translation unit. 1127/// 1128/// \param Id The name of the Objective-C class we're looking for. If 1129/// typo-correction fixes this name, the Id will be updated 1130/// to the fixed name. 1131/// 1132/// \param IdLoc The location of the name in the translation unit. 1133/// 1134/// \param TypoCorrection If true, this routine will attempt typo correction 1135/// if there is no class with the given name. 1136/// 1137/// \returns The declaration of the named Objective-C class, or NULL if the 1138/// class could not be found. 1139ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 1140 SourceLocation IdLoc, 1141 bool TypoCorrection) { 1142 // The third "scope" argument is 0 since we aren't enabling lazy built-in 1143 // creation from this context. 1144 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 1145 1146 if (!IDecl && TypoCorrection) { 1147 // Perform typo correction at the given location, but only if we 1148 // find an Objective-C class name. 1149 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 1150 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 1151 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 1152 Diag(IdLoc, diag::err_undef_interface_suggest) 1153 << Id << IDecl->getDeclName() 1154 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 1155 Diag(IDecl->getLocation(), diag::note_previous_decl) 1156 << IDecl->getDeclName(); 1157 1158 Id = IDecl->getIdentifier(); 1159 } 1160 } 1161 1162 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 1163} 1164 1165/// getNonFieldDeclScope - Retrieves the innermost scope, starting 1166/// from S, where a non-field would be declared. This routine copes 1167/// with the difference between C and C++ scoping rules in structs and 1168/// unions. For example, the following code is well-formed in C but 1169/// ill-formed in C++: 1170/// @code 1171/// struct S6 { 1172/// enum { BAR } e; 1173/// }; 1174/// 1175/// void test_S6() { 1176/// struct S6 a; 1177/// a.e = BAR; 1178/// } 1179/// @endcode 1180/// For the declaration of BAR, this routine will return a different 1181/// scope. The scope S will be the scope of the unnamed enumeration 1182/// within S6. In C++, this routine will return the scope associated 1183/// with S6, because the enumeration's scope is a transparent 1184/// context but structures can contain non-field names. In C, this 1185/// routine will return the translation unit scope, since the 1186/// enumeration's scope is a transparent context and structures cannot 1187/// contain non-field names. 1188Scope *Sema::getNonFieldDeclScope(Scope *S) { 1189 while (((S->getFlags() & Scope::DeclScope) == 0) || 1190 (S->getEntity() && 1191 ((DeclContext *)S->getEntity())->isTransparentContext()) || 1192 (S->isClassScope() && !getLangOptions().CPlusPlus)) 1193 S = S->getParent(); 1194 return S; 1195} 1196 1197/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 1198/// file scope. lazily create a decl for it. ForRedeclaration is true 1199/// if we're creating this built-in in anticipation of redeclaring the 1200/// built-in. 1201NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 1202 Scope *S, bool ForRedeclaration, 1203 SourceLocation Loc) { 1204 Builtin::ID BID = (Builtin::ID)bid; 1205 1206 ASTContext::GetBuiltinTypeError Error; 1207 QualType R = Context.GetBuiltinType(BID, Error); 1208 switch (Error) { 1209 case ASTContext::GE_None: 1210 // Okay 1211 break; 1212 1213 case ASTContext::GE_Missing_stdio: 1214 if (ForRedeclaration) 1215 Diag(Loc, diag::warn_implicit_decl_requires_stdio) 1216 << Context.BuiltinInfo.GetName(BID); 1217 return 0; 1218 1219 case ASTContext::GE_Missing_setjmp: 1220 if (ForRedeclaration) 1221 Diag(Loc, diag::warn_implicit_decl_requires_setjmp) 1222 << Context.BuiltinInfo.GetName(BID); 1223 return 0; 1224 } 1225 1226 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 1227 Diag(Loc, diag::ext_implicit_lib_function_decl) 1228 << Context.BuiltinInfo.GetName(BID) 1229 << R; 1230 if (Context.BuiltinInfo.getHeaderName(BID) && 1231 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) 1232 != Diagnostic::Ignored) 1233 Diag(Loc, diag::note_please_include_header) 1234 << Context.BuiltinInfo.getHeaderName(BID) 1235 << Context.BuiltinInfo.GetName(BID); 1236 } 1237 1238 FunctionDecl *New = FunctionDecl::Create(Context, 1239 Context.getTranslationUnitDecl(), 1240 Loc, Loc, II, R, /*TInfo=*/0, 1241 SC_Extern, 1242 SC_None, false, 1243 /*hasPrototype=*/true); 1244 New->setImplicit(); 1245 1246 // Create Decl objects for each parameter, adding them to the 1247 // FunctionDecl. 1248 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 1249 llvm::SmallVector<ParmVarDecl*, 16> Params; 1250 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) { 1251 ParmVarDecl *parm = 1252 ParmVarDecl::Create(Context, New, SourceLocation(), 1253 SourceLocation(), 0, 1254 FT->getArgType(i), /*TInfo=*/0, 1255 SC_None, SC_None, 0); 1256 parm->setScopeInfo(0, i); 1257 Params.push_back(parm); 1258 } 1259 New->setParams(Params.data(), Params.size()); 1260 } 1261 1262 AddKnownFunctionAttributes(New); 1263 1264 // TUScope is the translation-unit scope to insert this function into. 1265 // FIXME: This is hideous. We need to teach PushOnScopeChains to 1266 // relate Scopes to DeclContexts, and probably eliminate CurContext 1267 // entirely, but we're not there yet. 1268 DeclContext *SavedContext = CurContext; 1269 CurContext = Context.getTranslationUnitDecl(); 1270 PushOnScopeChains(New, TUScope); 1271 CurContext = SavedContext; 1272 return New; 1273} 1274 1275/// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the 1276/// same name and scope as a previous declaration 'Old'. Figure out 1277/// how to resolve this situation, merging decls or emitting 1278/// diagnostics as appropriate. If there was an error, set New to be invalid. 1279/// 1280void Sema::MergeTypedefNameDecl(TypedefNameDecl *New, LookupResult &OldDecls) { 1281 // If the new decl is known invalid already, don't bother doing any 1282 // merging checks. 1283 if (New->isInvalidDecl()) return; 1284 1285 // Allow multiple definitions for ObjC built-in typedefs. 1286 // FIXME: Verify the underlying types are equivalent! 1287 if (getLangOptions().ObjC1) { 1288 const IdentifierInfo *TypeID = New->getIdentifier(); 1289 switch (TypeID->getLength()) { 1290 default: break; 1291 case 2: 1292 if (!TypeID->isStr("id")) 1293 break; 1294 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 1295 // Install the built-in type for 'id', ignoring the current definition. 1296 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 1297 return; 1298 case 5: 1299 if (!TypeID->isStr("Class")) 1300 break; 1301 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 1302 // Install the built-in type for 'Class', ignoring the current definition. 1303 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 1304 return; 1305 case 3: 1306 if (!TypeID->isStr("SEL")) 1307 break; 1308 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 1309 // Install the built-in type for 'SEL', ignoring the current definition. 1310 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 1311 return; 1312 case 8: 1313 if (!TypeID->isStr("Protocol")) 1314 break; 1315 Context.setObjCProtoType(New->getUnderlyingType()); 1316 return; 1317 } 1318 // Fall through - the typedef name was not a builtin type. 1319 } 1320 1321 // Verify the old decl was also a type. 1322 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 1323 if (!Old) { 1324 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1325 << New->getDeclName(); 1326 1327 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 1328 if (OldD->getLocation().isValid()) 1329 Diag(OldD->getLocation(), diag::note_previous_definition); 1330 1331 return New->setInvalidDecl(); 1332 } 1333 1334 // If the old declaration is invalid, just give up here. 1335 if (Old->isInvalidDecl()) 1336 return New->setInvalidDecl(); 1337 1338 // Determine the "old" type we'll use for checking and diagnostics. 1339 QualType OldType; 1340 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old)) 1341 OldType = OldTypedef->getUnderlyingType(); 1342 else 1343 OldType = Context.getTypeDeclType(Old); 1344 1345 // If the typedef types are not identical, reject them in all languages and 1346 // with any extensions enabled. 1347 1348 if (OldType != New->getUnderlyingType() && 1349 Context.getCanonicalType(OldType) != 1350 Context.getCanonicalType(New->getUnderlyingType())) { 1351 int Kind = 0; 1352 if (isa<TypeAliasDecl>(Old)) 1353 Kind = 1; 1354 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 1355 << Kind << New->getUnderlyingType() << OldType; 1356 if (Old->getLocation().isValid()) 1357 Diag(Old->getLocation(), diag::note_previous_definition); 1358 return New->setInvalidDecl(); 1359 } 1360 1361 // The types match. Link up the redeclaration chain if the old 1362 // declaration was a typedef. 1363 // FIXME: this is a potential source of wierdness if the type 1364 // spellings don't match exactly. 1365 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) 1366 New->setPreviousDeclaration(Typedef); 1367 1368 if (getLangOptions().Microsoft) 1369 return; 1370 1371 if (getLangOptions().CPlusPlus) { 1372 // C++ [dcl.typedef]p2: 1373 // In a given non-class scope, a typedef specifier can be used to 1374 // redefine the name of any type declared in that scope to refer 1375 // to the type to which it already refers. 1376 if (!isa<CXXRecordDecl>(CurContext)) 1377 return; 1378 1379 // C++0x [dcl.typedef]p4: 1380 // In a given class scope, a typedef specifier can be used to redefine 1381 // any class-name declared in that scope that is not also a typedef-name 1382 // to refer to the type to which it already refers. 1383 // 1384 // This wording came in via DR424, which was a correction to the 1385 // wording in DR56, which accidentally banned code like: 1386 // 1387 // struct S { 1388 // typedef struct A { } A; 1389 // }; 1390 // 1391 // in the C++03 standard. We implement the C++0x semantics, which 1392 // allow the above but disallow 1393 // 1394 // struct S { 1395 // typedef int I; 1396 // typedef int I; 1397 // }; 1398 // 1399 // since that was the intent of DR56. 1400 if (!isa<TypedefNameDecl>(Old)) 1401 return; 1402 1403 Diag(New->getLocation(), diag::err_redefinition) 1404 << New->getDeclName(); 1405 Diag(Old->getLocation(), diag::note_previous_definition); 1406 return New->setInvalidDecl(); 1407 } 1408 1409 // If we have a redefinition of a typedef in C, emit a warning. This warning 1410 // is normally mapped to an error, but can be controlled with 1411 // -Wtypedef-redefinition. If either the original or the redefinition is 1412 // in a system header, don't emit this for compatibility with GCC. 1413 if (getDiagnostics().getSuppressSystemWarnings() && 1414 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 1415 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 1416 return; 1417 1418 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1419 << New->getDeclName(); 1420 Diag(Old->getLocation(), diag::note_previous_definition); 1421 return; 1422} 1423 1424/// DeclhasAttr - returns true if decl Declaration already has the target 1425/// attribute. 1426static bool 1427DeclHasAttr(const Decl *D, const Attr *A) { 1428 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1429 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1430 if ((*i)->getKind() == A->getKind()) { 1431 // FIXME: Don't hardcode this check 1432 if (OA && isa<OwnershipAttr>(*i)) 1433 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1434 return true; 1435 } 1436 1437 return false; 1438} 1439 1440/// mergeDeclAttributes - Copy attributes from the Old decl to the New one. 1441static void mergeDeclAttributes(Decl *newDecl, const Decl *oldDecl, 1442 ASTContext &C) { 1443 if (!oldDecl->hasAttrs()) 1444 return; 1445 1446 bool foundAny = newDecl->hasAttrs(); 1447 1448 // Ensure that any moving of objects within the allocated map is done before 1449 // we process them. 1450 if (!foundAny) newDecl->setAttrs(AttrVec()); 1451 1452 for (specific_attr_iterator<InheritableAttr> 1453 i = oldDecl->specific_attr_begin<InheritableAttr>(), 1454 e = oldDecl->specific_attr_end<InheritableAttr>(); i != e; ++i) { 1455 if (!DeclHasAttr(newDecl, *i)) { 1456 InheritableAttr *newAttr = cast<InheritableAttr>((*i)->clone(C)); 1457 newAttr->setInherited(true); 1458 newDecl->addAttr(newAttr); 1459 foundAny = true; 1460 } 1461 } 1462 1463 if (!foundAny) newDecl->dropAttrs(); 1464} 1465 1466/// mergeParamDeclAttributes - Copy attributes from the old parameter 1467/// to the new one. 1468static void mergeParamDeclAttributes(ParmVarDecl *newDecl, 1469 const ParmVarDecl *oldDecl, 1470 ASTContext &C) { 1471 if (!oldDecl->hasAttrs()) 1472 return; 1473 1474 bool foundAny = newDecl->hasAttrs(); 1475 1476 // Ensure that any moving of objects within the allocated map is 1477 // done before we process them. 1478 if (!foundAny) newDecl->setAttrs(AttrVec()); 1479 1480 for (specific_attr_iterator<InheritableParamAttr> 1481 i = oldDecl->specific_attr_begin<InheritableParamAttr>(), 1482 e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { 1483 if (!DeclHasAttr(newDecl, *i)) { 1484 InheritableAttr *newAttr = cast<InheritableParamAttr>((*i)->clone(C)); 1485 newAttr->setInherited(true); 1486 newDecl->addAttr(newAttr); 1487 foundAny = true; 1488 } 1489 } 1490 1491 if (!foundAny) newDecl->dropAttrs(); 1492} 1493 1494namespace { 1495 1496/// Used in MergeFunctionDecl to keep track of function parameters in 1497/// C. 1498struct GNUCompatibleParamWarning { 1499 ParmVarDecl *OldParm; 1500 ParmVarDecl *NewParm; 1501 QualType PromotedType; 1502}; 1503 1504} 1505 1506/// getSpecialMember - get the special member enum for a method. 1507Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1508 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1509 if (Ctor->isCopyConstructor()) 1510 return Sema::CXXCopyConstructor; 1511 1512 return Sema::CXXConstructor; 1513 } 1514 1515 if (isa<CXXDestructorDecl>(MD)) 1516 return Sema::CXXDestructor; 1517 1518 assert(MD->isCopyAssignmentOperator() && 1519 "Must have copy assignment operator"); 1520 return Sema::CXXCopyAssignment; 1521} 1522 1523/// canRedefineFunction - checks if a function can be redefined. Currently, 1524/// only extern inline functions can be redefined, and even then only in 1525/// GNU89 mode. 1526static bool canRedefineFunction(const FunctionDecl *FD, 1527 const LangOptions& LangOpts) { 1528 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1529 FD->isInlineSpecified() && 1530 FD->getStorageClass() == SC_Extern); 1531} 1532 1533/// MergeFunctionDecl - We just parsed a function 'New' from 1534/// declarator D which has the same name and scope as a previous 1535/// declaration 'Old'. Figure out how to resolve this situation, 1536/// merging decls or emitting diagnostics as appropriate. 1537/// 1538/// In C++, New and Old must be declarations that are not 1539/// overloaded. Use IsOverload to determine whether New and Old are 1540/// overloaded, and to select the Old declaration that New should be 1541/// merged with. 1542/// 1543/// Returns true if there was an error, false otherwise. 1544bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1545 // Verify the old decl was also a function. 1546 FunctionDecl *Old = 0; 1547 if (FunctionTemplateDecl *OldFunctionTemplate 1548 = dyn_cast<FunctionTemplateDecl>(OldD)) 1549 Old = OldFunctionTemplate->getTemplatedDecl(); 1550 else 1551 Old = dyn_cast<FunctionDecl>(OldD); 1552 if (!Old) { 1553 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1554 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1555 Diag(Shadow->getTargetDecl()->getLocation(), 1556 diag::note_using_decl_target); 1557 Diag(Shadow->getUsingDecl()->getLocation(), 1558 diag::note_using_decl) << 0; 1559 return true; 1560 } 1561 1562 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1563 << New->getDeclName(); 1564 Diag(OldD->getLocation(), diag::note_previous_definition); 1565 return true; 1566 } 1567 1568 // Determine whether the previous declaration was a definition, 1569 // implicit declaration, or a declaration. 1570 diag::kind PrevDiag; 1571 if (Old->isThisDeclarationADefinition()) 1572 PrevDiag = diag::note_previous_definition; 1573 else if (Old->isImplicit()) 1574 PrevDiag = diag::note_previous_implicit_declaration; 1575 else 1576 PrevDiag = diag::note_previous_declaration; 1577 1578 QualType OldQType = Context.getCanonicalType(Old->getType()); 1579 QualType NewQType = Context.getCanonicalType(New->getType()); 1580 1581 // Don't complain about this if we're in GNU89 mode and the old function 1582 // is an extern inline function. 1583 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1584 New->getStorageClass() == SC_Static && 1585 Old->getStorageClass() != SC_Static && 1586 !canRedefineFunction(Old, getLangOptions())) { 1587 if (getLangOptions().Microsoft) { 1588 Diag(New->getLocation(), diag::warn_static_non_static) << New; 1589 Diag(Old->getLocation(), PrevDiag); 1590 } else { 1591 Diag(New->getLocation(), diag::err_static_non_static) << New; 1592 Diag(Old->getLocation(), PrevDiag); 1593 return true; 1594 } 1595 } 1596 1597 // If a function is first declared with a calling convention, but is 1598 // later declared or defined without one, the second decl assumes the 1599 // calling convention of the first. 1600 // 1601 // For the new decl, we have to look at the NON-canonical type to tell the 1602 // difference between a function that really doesn't have a calling 1603 // convention and one that is declared cdecl. That's because in 1604 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1605 // because it is the default calling convention. 1606 // 1607 // Note also that we DO NOT return at this point, because we still have 1608 // other tests to run. 1609 const FunctionType *OldType = cast<FunctionType>(OldQType); 1610 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1611 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1612 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1613 bool RequiresAdjustment = false; 1614 if (OldTypeInfo.getCC() != CC_Default && 1615 NewTypeInfo.getCC() == CC_Default) { 1616 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 1617 RequiresAdjustment = true; 1618 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1619 NewTypeInfo.getCC())) { 1620 // Calling conventions really aren't compatible, so complain. 1621 Diag(New->getLocation(), diag::err_cconv_change) 1622 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1623 << (OldTypeInfo.getCC() == CC_Default) 1624 << (OldTypeInfo.getCC() == CC_Default ? "" : 1625 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1626 Diag(Old->getLocation(), diag::note_previous_declaration); 1627 return true; 1628 } 1629 1630 // FIXME: diagnose the other way around? 1631 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 1632 NewTypeInfo = NewTypeInfo.withNoReturn(true); 1633 RequiresAdjustment = true; 1634 } 1635 1636 // Merge regparm attribute. 1637 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() || 1638 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 1639 if (NewTypeInfo.getHasRegParm()) { 1640 Diag(New->getLocation(), diag::err_regparm_mismatch) 1641 << NewType->getRegParmType() 1642 << OldType->getRegParmType(); 1643 Diag(Old->getLocation(), diag::note_previous_declaration); 1644 return true; 1645 } 1646 1647 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 1648 RequiresAdjustment = true; 1649 } 1650 1651 if (RequiresAdjustment) { 1652 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 1653 New->setType(QualType(NewType, 0)); 1654 NewQType = Context.getCanonicalType(New->getType()); 1655 } 1656 1657 if (getLangOptions().CPlusPlus) { 1658 // (C++98 13.1p2): 1659 // Certain function declarations cannot be overloaded: 1660 // -- Function declarations that differ only in the return type 1661 // cannot be overloaded. 1662 QualType OldReturnType = OldType->getResultType(); 1663 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 1664 QualType ResQT; 1665 if (OldReturnType != NewReturnType) { 1666 if (NewReturnType->isObjCObjectPointerType() 1667 && OldReturnType->isObjCObjectPointerType()) 1668 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1669 if (ResQT.isNull()) { 1670 if (New->isCXXClassMember() && New->isOutOfLine()) 1671 Diag(New->getLocation(), 1672 diag::err_member_def_does_not_match_ret_type) << New; 1673 else 1674 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1675 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1676 return true; 1677 } 1678 else 1679 NewQType = ResQT; 1680 } 1681 1682 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1683 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1684 if (OldMethod && NewMethod) { 1685 // Preserve triviality. 1686 NewMethod->setTrivial(OldMethod->isTrivial()); 1687 1688 bool isFriend = NewMethod->getFriendObjectKind(); 1689 1690 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1691 // -- Member function declarations with the same name and the 1692 // same parameter types cannot be overloaded if any of them 1693 // is a static member function declaration. 1694 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1695 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1696 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1697 return true; 1698 } 1699 1700 // C++ [class.mem]p1: 1701 // [...] A member shall not be declared twice in the 1702 // member-specification, except that a nested class or member 1703 // class template can be declared and then later defined. 1704 unsigned NewDiag; 1705 if (isa<CXXConstructorDecl>(OldMethod)) 1706 NewDiag = diag::err_constructor_redeclared; 1707 else if (isa<CXXDestructorDecl>(NewMethod)) 1708 NewDiag = diag::err_destructor_redeclared; 1709 else if (isa<CXXConversionDecl>(NewMethod)) 1710 NewDiag = diag::err_conv_function_redeclared; 1711 else 1712 NewDiag = diag::err_member_redeclared; 1713 1714 Diag(New->getLocation(), NewDiag); 1715 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1716 1717 // Complain if this is an explicit declaration of a special 1718 // member that was initially declared implicitly. 1719 // 1720 // As an exception, it's okay to befriend such methods in order 1721 // to permit the implicit constructor/destructor/operator calls. 1722 } else if (OldMethod->isImplicit()) { 1723 if (isFriend) { 1724 NewMethod->setImplicit(); 1725 } else { 1726 Diag(NewMethod->getLocation(), 1727 diag::err_definition_of_implicitly_declared_member) 1728 << New << getSpecialMember(OldMethod); 1729 return true; 1730 } 1731 } 1732 } 1733 1734 // (C++98 8.3.5p3): 1735 // All declarations for a function shall agree exactly in both the 1736 // return type and the parameter-type-list. 1737 // We also want to respect all the extended bits except noreturn. 1738 1739 // noreturn should now match unless the old type info didn't have it. 1740 QualType OldQTypeForComparison = OldQType; 1741 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 1742 assert(OldQType == QualType(OldType, 0)); 1743 const FunctionType *OldTypeForComparison 1744 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 1745 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 1746 assert(OldQTypeForComparison.isCanonical()); 1747 } 1748 1749 if (OldQTypeForComparison == NewQType) 1750 return MergeCompatibleFunctionDecls(New, Old); 1751 1752 // Fall through for conflicting redeclarations and redefinitions. 1753 } 1754 1755 // C: Function types need to be compatible, not identical. This handles 1756 // duplicate function decls like "void f(int); void f(enum X);" properly. 1757 if (!getLangOptions().CPlusPlus && 1758 Context.typesAreCompatible(OldQType, NewQType)) { 1759 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1760 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1761 const FunctionProtoType *OldProto = 0; 1762 if (isa<FunctionNoProtoType>(NewFuncType) && 1763 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1764 // The old declaration provided a function prototype, but the 1765 // new declaration does not. Merge in the prototype. 1766 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1767 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1768 OldProto->arg_type_end()); 1769 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1770 ParamTypes.data(), ParamTypes.size(), 1771 OldProto->getExtProtoInfo()); 1772 New->setType(NewQType); 1773 New->setHasInheritedPrototype(); 1774 1775 // Synthesize a parameter for each argument type. 1776 llvm::SmallVector<ParmVarDecl*, 16> Params; 1777 for (FunctionProtoType::arg_type_iterator 1778 ParamType = OldProto->arg_type_begin(), 1779 ParamEnd = OldProto->arg_type_end(); 1780 ParamType != ParamEnd; ++ParamType) { 1781 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1782 SourceLocation(), 1783 SourceLocation(), 0, 1784 *ParamType, /*TInfo=*/0, 1785 SC_None, SC_None, 1786 0); 1787 Param->setScopeInfo(0, Params.size()); 1788 Param->setImplicit(); 1789 Params.push_back(Param); 1790 } 1791 1792 New->setParams(Params.data(), Params.size()); 1793 } 1794 1795 return MergeCompatibleFunctionDecls(New, Old); 1796 } 1797 1798 // GNU C permits a K&R definition to follow a prototype declaration 1799 // if the declared types of the parameters in the K&R definition 1800 // match the types in the prototype declaration, even when the 1801 // promoted types of the parameters from the K&R definition differ 1802 // from the types in the prototype. GCC then keeps the types from 1803 // the prototype. 1804 // 1805 // If a variadic prototype is followed by a non-variadic K&R definition, 1806 // the K&R definition becomes variadic. This is sort of an edge case, but 1807 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1808 // C99 6.9.1p8. 1809 if (!getLangOptions().CPlusPlus && 1810 Old->hasPrototype() && !New->hasPrototype() && 1811 New->getType()->getAs<FunctionProtoType>() && 1812 Old->getNumParams() == New->getNumParams()) { 1813 llvm::SmallVector<QualType, 16> ArgTypes; 1814 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1815 const FunctionProtoType *OldProto 1816 = Old->getType()->getAs<FunctionProtoType>(); 1817 const FunctionProtoType *NewProto 1818 = New->getType()->getAs<FunctionProtoType>(); 1819 1820 // Determine whether this is the GNU C extension. 1821 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1822 NewProto->getResultType()); 1823 bool LooseCompatible = !MergedReturn.isNull(); 1824 for (unsigned Idx = 0, End = Old->getNumParams(); 1825 LooseCompatible && Idx != End; ++Idx) { 1826 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1827 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1828 if (Context.typesAreCompatible(OldParm->getType(), 1829 NewProto->getArgType(Idx))) { 1830 ArgTypes.push_back(NewParm->getType()); 1831 } else if (Context.typesAreCompatible(OldParm->getType(), 1832 NewParm->getType(), 1833 /*CompareUnqualified=*/true)) { 1834 GNUCompatibleParamWarning Warn 1835 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1836 Warnings.push_back(Warn); 1837 ArgTypes.push_back(NewParm->getType()); 1838 } else 1839 LooseCompatible = false; 1840 } 1841 1842 if (LooseCompatible) { 1843 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1844 Diag(Warnings[Warn].NewParm->getLocation(), 1845 diag::ext_param_promoted_not_compatible_with_prototype) 1846 << Warnings[Warn].PromotedType 1847 << Warnings[Warn].OldParm->getType(); 1848 if (Warnings[Warn].OldParm->getLocation().isValid()) 1849 Diag(Warnings[Warn].OldParm->getLocation(), 1850 diag::note_previous_declaration); 1851 } 1852 1853 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1854 ArgTypes.size(), 1855 OldProto->getExtProtoInfo())); 1856 return MergeCompatibleFunctionDecls(New, Old); 1857 } 1858 1859 // Fall through to diagnose conflicting types. 1860 } 1861 1862 // A function that has already been declared has been redeclared or defined 1863 // with a different type- show appropriate diagnostic 1864 if (unsigned BuiltinID = Old->getBuiltinID()) { 1865 // The user has declared a builtin function with an incompatible 1866 // signature. 1867 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1868 // The function the user is redeclaring is a library-defined 1869 // function like 'malloc' or 'printf'. Warn about the 1870 // redeclaration, then pretend that we don't know about this 1871 // library built-in. 1872 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1873 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1874 << Old << Old->getType(); 1875 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1876 Old->setInvalidDecl(); 1877 return false; 1878 } 1879 1880 PrevDiag = diag::note_previous_builtin_declaration; 1881 } 1882 1883 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1884 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1885 return true; 1886} 1887 1888/// \brief Completes the merge of two function declarations that are 1889/// known to be compatible. 1890/// 1891/// This routine handles the merging of attributes and other 1892/// properties of function declarations form the old declaration to 1893/// the new declaration, once we know that New is in fact a 1894/// redeclaration of Old. 1895/// 1896/// \returns false 1897bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1898 // Merge the attributes 1899 mergeDeclAttributes(New, Old, Context); 1900 1901 // Merge the storage class. 1902 if (Old->getStorageClass() != SC_Extern && 1903 Old->getStorageClass() != SC_None) 1904 New->setStorageClass(Old->getStorageClass()); 1905 1906 // Merge "pure" flag. 1907 if (Old->isPure()) 1908 New->setPure(); 1909 1910 // Merge the "deleted" flag. 1911 if (Old->isDeleted()) 1912 New->setDeleted(); 1913 1914 // Merge attributes from the parameters. These can mismatch with K&R 1915 // declarations. 1916 if (New->getNumParams() == Old->getNumParams()) 1917 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 1918 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 1919 Context); 1920 1921 if (getLangOptions().CPlusPlus) 1922 return MergeCXXFunctionDecl(New, Old); 1923 1924 return false; 1925} 1926 1927void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 1928 const ObjCMethodDecl *oldMethod) { 1929 // Merge the attributes. 1930 mergeDeclAttributes(newMethod, oldMethod, Context); 1931 1932 // Merge attributes from the parameters. 1933 for (ObjCMethodDecl::param_iterator oi = oldMethod->param_begin(), 1934 ni = newMethod->param_begin(), ne = newMethod->param_end(); 1935 ni != ne; ++ni, ++oi) 1936 mergeParamDeclAttributes(*ni, *oi, Context); 1937} 1938 1939/// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and 1940/// scope as a previous declaration 'Old'. Figure out how to merge their types, 1941/// emitting diagnostics as appropriate. 1942/// 1943/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 1944/// to here in AddInitializerToDecl and AddCXXDirectInitializerToDecl. We can't 1945/// check them before the initializer is attached. 1946/// 1947void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old) { 1948 if (New->isInvalidDecl() || Old->isInvalidDecl()) 1949 return; 1950 1951 QualType MergedT; 1952 if (getLangOptions().CPlusPlus) { 1953 AutoType *AT = New->getType()->getContainedAutoType(); 1954 if (AT && !AT->isDeduced()) { 1955 // We don't know what the new type is until the initializer is attached. 1956 return; 1957 } else if (Context.hasSameType(New->getType(), Old->getType())) { 1958 // These could still be something that needs exception specs checked. 1959 return MergeVarDeclExceptionSpecs(New, Old); 1960 } 1961 // C++ [basic.link]p10: 1962 // [...] the types specified by all declarations referring to a given 1963 // object or function shall be identical, except that declarations for an 1964 // array object can specify array types that differ by the presence or 1965 // absence of a major array bound (8.3.4). 1966 else if (Old->getType()->isIncompleteArrayType() && 1967 New->getType()->isArrayType()) { 1968 CanQual<ArrayType> OldArray 1969 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1970 CanQual<ArrayType> NewArray 1971 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1972 if (OldArray->getElementType() == NewArray->getElementType()) 1973 MergedT = New->getType(); 1974 } else if (Old->getType()->isArrayType() && 1975 New->getType()->isIncompleteArrayType()) { 1976 CanQual<ArrayType> OldArray 1977 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1978 CanQual<ArrayType> NewArray 1979 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1980 if (OldArray->getElementType() == NewArray->getElementType()) 1981 MergedT = Old->getType(); 1982 } else if (New->getType()->isObjCObjectPointerType() 1983 && Old->getType()->isObjCObjectPointerType()) { 1984 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 1985 Old->getType()); 1986 } 1987 } else { 1988 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1989 } 1990 if (MergedT.isNull()) { 1991 Diag(New->getLocation(), diag::err_redefinition_different_type) 1992 << New->getDeclName(); 1993 Diag(Old->getLocation(), diag::note_previous_definition); 1994 return New->setInvalidDecl(); 1995 } 1996 New->setType(MergedT); 1997} 1998 1999/// MergeVarDecl - We just parsed a variable 'New' which has the same name 2000/// and scope as a previous declaration 'Old'. Figure out how to resolve this 2001/// situation, merging decls or emitting diagnostics as appropriate. 2002/// 2003/// Tentative definition rules (C99 6.9.2p2) are checked by 2004/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 2005/// definitions here, since the initializer hasn't been attached. 2006/// 2007void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 2008 // If the new decl is already invalid, don't do any other checking. 2009 if (New->isInvalidDecl()) 2010 return; 2011 2012 // Verify the old decl was also a variable. 2013 VarDecl *Old = 0; 2014 if (!Previous.isSingleResult() || 2015 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 2016 Diag(New->getLocation(), diag::err_redefinition_different_kind) 2017 << New->getDeclName(); 2018 Diag(Previous.getRepresentativeDecl()->getLocation(), 2019 diag::note_previous_definition); 2020 return New->setInvalidDecl(); 2021 } 2022 2023 // C++ [class.mem]p1: 2024 // A member shall not be declared twice in the member-specification [...] 2025 // 2026 // Here, we need only consider static data members. 2027 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 2028 Diag(New->getLocation(), diag::err_duplicate_member) 2029 << New->getIdentifier(); 2030 Diag(Old->getLocation(), diag::note_previous_declaration); 2031 New->setInvalidDecl(); 2032 } 2033 2034 mergeDeclAttributes(New, Old, Context); 2035 2036 // Merge the types. 2037 MergeVarDeclTypes(New, Old); 2038 if (New->isInvalidDecl()) 2039 return; 2040 2041 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 2042 if (New->getStorageClass() == SC_Static && 2043 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 2044 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 2045 Diag(Old->getLocation(), diag::note_previous_definition); 2046 return New->setInvalidDecl(); 2047 } 2048 // C99 6.2.2p4: 2049 // For an identifier declared with the storage-class specifier 2050 // extern in a scope in which a prior declaration of that 2051 // identifier is visible,23) if the prior declaration specifies 2052 // internal or external linkage, the linkage of the identifier at 2053 // the later declaration is the same as the linkage specified at 2054 // the prior declaration. If no prior declaration is visible, or 2055 // if the prior declaration specifies no linkage, then the 2056 // identifier has external linkage. 2057 if (New->hasExternalStorage() && Old->hasLinkage()) 2058 /* Okay */; 2059 else if (New->getStorageClass() != SC_Static && 2060 Old->getStorageClass() == SC_Static) { 2061 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 2062 Diag(Old->getLocation(), diag::note_previous_definition); 2063 return New->setInvalidDecl(); 2064 } 2065 2066 // Check if extern is followed by non-extern and vice-versa. 2067 if (New->hasExternalStorage() && 2068 !Old->hasLinkage() && Old->isLocalVarDecl()) { 2069 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 2070 Diag(Old->getLocation(), diag::note_previous_definition); 2071 return New->setInvalidDecl(); 2072 } 2073 if (Old->hasExternalStorage() && 2074 !New->hasLinkage() && New->isLocalVarDecl()) { 2075 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 2076 Diag(Old->getLocation(), diag::note_previous_definition); 2077 return New->setInvalidDecl(); 2078 } 2079 2080 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 2081 2082 // FIXME: The test for external storage here seems wrong? We still 2083 // need to check for mismatches. 2084 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 2085 // Don't complain about out-of-line definitions of static members. 2086 !(Old->getLexicalDeclContext()->isRecord() && 2087 !New->getLexicalDeclContext()->isRecord())) { 2088 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 2089 Diag(Old->getLocation(), diag::note_previous_definition); 2090 return New->setInvalidDecl(); 2091 } 2092 2093 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 2094 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 2095 Diag(Old->getLocation(), diag::note_previous_definition); 2096 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 2097 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 2098 Diag(Old->getLocation(), diag::note_previous_definition); 2099 } 2100 2101 // C++ doesn't have tentative definitions, so go right ahead and check here. 2102 const VarDecl *Def; 2103 if (getLangOptions().CPlusPlus && 2104 New->isThisDeclarationADefinition() == VarDecl::Definition && 2105 (Def = Old->getDefinition())) { 2106 Diag(New->getLocation(), diag::err_redefinition) 2107 << New->getDeclName(); 2108 Diag(Def->getLocation(), diag::note_previous_definition); 2109 New->setInvalidDecl(); 2110 return; 2111 } 2112 // c99 6.2.2 P4. 2113 // For an identifier declared with the storage-class specifier extern in a 2114 // scope in which a prior declaration of that identifier is visible, if 2115 // the prior declaration specifies internal or external linkage, the linkage 2116 // of the identifier at the later declaration is the same as the linkage 2117 // specified at the prior declaration. 2118 // FIXME. revisit this code. 2119 if (New->hasExternalStorage() && 2120 Old->getLinkage() == InternalLinkage && 2121 New->getDeclContext() == Old->getDeclContext()) 2122 New->setStorageClass(Old->getStorageClass()); 2123 2124 // Keep a chain of previous declarations. 2125 New->setPreviousDeclaration(Old); 2126 2127 // Inherit access appropriately. 2128 New->setAccess(Old->getAccess()); 2129} 2130 2131/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 2132/// no declarator (e.g. "struct foo;") is parsed. 2133Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 2134 DeclSpec &DS) { 2135 return ParsedFreeStandingDeclSpec(S, AS, DS, 2136 MultiTemplateParamsArg(*this, 0, 0)); 2137} 2138 2139/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 2140/// no declarator (e.g. "struct foo;") is parsed. It also accopts template 2141/// parameters to cope with template friend declarations. 2142Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 2143 DeclSpec &DS, 2144 MultiTemplateParamsArg TemplateParams) { 2145 Decl *TagD = 0; 2146 TagDecl *Tag = 0; 2147 if (DS.getTypeSpecType() == DeclSpec::TST_class || 2148 DS.getTypeSpecType() == DeclSpec::TST_struct || 2149 DS.getTypeSpecType() == DeclSpec::TST_union || 2150 DS.getTypeSpecType() == DeclSpec::TST_enum) { 2151 TagD = DS.getRepAsDecl(); 2152 2153 if (!TagD) // We probably had an error 2154 return 0; 2155 2156 // Note that the above type specs guarantee that the 2157 // type rep is a Decl, whereas in many of the others 2158 // it's a Type. 2159 Tag = dyn_cast<TagDecl>(TagD); 2160 } 2161 2162 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 2163 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 2164 // or incomplete types shall not be restrict-qualified." 2165 if (TypeQuals & DeclSpec::TQ_restrict) 2166 Diag(DS.getRestrictSpecLoc(), 2167 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 2168 << DS.getSourceRange(); 2169 } 2170 2171 if (DS.isFriendSpecified()) { 2172 // If we're dealing with a decl but not a TagDecl, assume that 2173 // whatever routines created it handled the friendship aspect. 2174 if (TagD && !Tag) 2175 return 0; 2176 return ActOnFriendTypeDecl(S, DS, TemplateParams); 2177 } 2178 2179 // Track whether we warned about the fact that there aren't any 2180 // declarators. 2181 bool emittedWarning = false; 2182 2183 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 2184 ProcessDeclAttributeList(S, Record, DS.getAttributes().getList()); 2185 2186 if (!Record->getDeclName() && Record->isDefinition() && 2187 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 2188 if (getLangOptions().CPlusPlus || 2189 Record->getDeclContext()->isRecord()) 2190 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 2191 2192 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 2193 << DS.getSourceRange(); 2194 emittedWarning = true; 2195 } 2196 } 2197 2198 // Check for Microsoft C extension: anonymous struct. 2199 if (getLangOptions().Microsoft && !getLangOptions().CPlusPlus && 2200 CurContext->isRecord() && 2201 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 2202 // Handle 2 kinds of anonymous struct: 2203 // struct STRUCT; 2204 // and 2205 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 2206 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 2207 if ((Record && Record->getDeclName() && !Record->isDefinition()) || 2208 (DS.getTypeSpecType() == DeclSpec::TST_typename && 2209 DS.getRepAsType().get()->isStructureType())) { 2210 Diag(DS.getSourceRange().getBegin(), diag::ext_ms_anonymous_struct) 2211 << DS.getSourceRange(); 2212 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 2213 } 2214 } 2215 2216 if (getLangOptions().CPlusPlus && 2217 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 2218 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 2219 if (Enum->enumerator_begin() == Enum->enumerator_end() && 2220 !Enum->getIdentifier() && !Enum->isInvalidDecl()) { 2221 Diag(Enum->getLocation(), diag::ext_no_declarators) 2222 << DS.getSourceRange(); 2223 emittedWarning = true; 2224 } 2225 2226 // Skip all the checks below if we have a type error. 2227 if (DS.getTypeSpecType() == DeclSpec::TST_error) return TagD; 2228 2229 if (!DS.isMissingDeclaratorOk()) { 2230 // Warn about typedefs of enums without names, since this is an 2231 // extension in both Microsoft and GNU. 2232 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 2233 Tag && isa<EnumDecl>(Tag)) { 2234 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 2235 << DS.getSourceRange(); 2236 return Tag; 2237 } 2238 2239 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 2240 << DS.getSourceRange(); 2241 emittedWarning = true; 2242 } 2243 2244 // We're going to complain about a bunch of spurious specifiers; 2245 // only do this if we're declaring a tag, because otherwise we 2246 // should be getting diag::ext_no_declarators. 2247 if (emittedWarning || (TagD && TagD->isInvalidDecl())) 2248 return TagD; 2249 2250 // Note that a linkage-specification sets a storage class, but 2251 // 'extern "C" struct foo;' is actually valid and not theoretically 2252 // useless. 2253 if (DeclSpec::SCS scs = DS.getStorageClassSpec()) 2254 if (!DS.isExternInLinkageSpec()) 2255 Diag(DS.getStorageClassSpecLoc(), diag::warn_standalone_specifier) 2256 << DeclSpec::getSpecifierName(scs); 2257 2258 if (DS.isThreadSpecified()) 2259 Diag(DS.getThreadSpecLoc(), diag::warn_standalone_specifier) << "__thread"; 2260 if (DS.getTypeQualifiers()) { 2261 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 2262 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "const"; 2263 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 2264 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "volatile"; 2265 // Restrict is covered above. 2266 } 2267 if (DS.isInlineSpecified()) 2268 Diag(DS.getInlineSpecLoc(), diag::warn_standalone_specifier) << "inline"; 2269 if (DS.isVirtualSpecified()) 2270 Diag(DS.getVirtualSpecLoc(), diag::warn_standalone_specifier) << "virtual"; 2271 if (DS.isExplicitSpecified()) 2272 Diag(DS.getExplicitSpecLoc(), diag::warn_standalone_specifier) <<"explicit"; 2273 2274 // FIXME: Warn on useless attributes 2275 2276 return TagD; 2277} 2278 2279/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 2280/// builds a statement for it and returns it so it is evaluated. 2281StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 2282 StmtResult R; 2283 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 2284 Expr *Exp = DS.getRepAsExpr(); 2285 QualType Ty = Exp->getType(); 2286 if (Ty->isPointerType()) { 2287 do 2288 Ty = Ty->getAs<PointerType>()->getPointeeType(); 2289 while (Ty->isPointerType()); 2290 } 2291 if (Ty->isVariableArrayType()) { 2292 R = ActOnExprStmt(MakeFullExpr(Exp)); 2293 } 2294 } 2295 return R; 2296} 2297 2298/// We are trying to inject an anonymous member into the given scope; 2299/// check if there's an existing declaration that can't be overloaded. 2300/// 2301/// \return true if this is a forbidden redeclaration 2302static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 2303 Scope *S, 2304 DeclContext *Owner, 2305 DeclarationName Name, 2306 SourceLocation NameLoc, 2307 unsigned diagnostic) { 2308 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 2309 Sema::ForRedeclaration); 2310 if (!SemaRef.LookupName(R, S)) return false; 2311 2312 if (R.getAsSingle<TagDecl>()) 2313 return false; 2314 2315 // Pick a representative declaration. 2316 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 2317 assert(PrevDecl && "Expected a non-null Decl"); 2318 2319 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 2320 return false; 2321 2322 SemaRef.Diag(NameLoc, diagnostic) << Name; 2323 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 2324 2325 return true; 2326} 2327 2328/// InjectAnonymousStructOrUnionMembers - Inject the members of the 2329/// anonymous struct or union AnonRecord into the owning context Owner 2330/// and scope S. This routine will be invoked just after we realize 2331/// that an unnamed union or struct is actually an anonymous union or 2332/// struct, e.g., 2333/// 2334/// @code 2335/// union { 2336/// int i; 2337/// float f; 2338/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 2339/// // f into the surrounding scope.x 2340/// @endcode 2341/// 2342/// This routine is recursive, injecting the names of nested anonymous 2343/// structs/unions into the owning context and scope as well. 2344static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 2345 DeclContext *Owner, 2346 RecordDecl *AnonRecord, 2347 AccessSpecifier AS, 2348 llvm::SmallVector<NamedDecl*, 2> &Chaining, 2349 bool MSAnonStruct) { 2350 unsigned diagKind 2351 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 2352 : diag::err_anonymous_struct_member_redecl; 2353 2354 bool Invalid = false; 2355 2356 // Look every FieldDecl and IndirectFieldDecl with a name. 2357 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 2358 DEnd = AnonRecord->decls_end(); 2359 D != DEnd; ++D) { 2360 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 2361 cast<NamedDecl>(*D)->getDeclName()) { 2362 ValueDecl *VD = cast<ValueDecl>(*D); 2363 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 2364 VD->getLocation(), diagKind)) { 2365 // C++ [class.union]p2: 2366 // The names of the members of an anonymous union shall be 2367 // distinct from the names of any other entity in the 2368 // scope in which the anonymous union is declared. 2369 Invalid = true; 2370 } else { 2371 // C++ [class.union]p2: 2372 // For the purpose of name lookup, after the anonymous union 2373 // definition, the members of the anonymous union are 2374 // considered to have been defined in the scope in which the 2375 // anonymous union is declared. 2376 unsigned OldChainingSize = Chaining.size(); 2377 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 2378 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 2379 PE = IF->chain_end(); PI != PE; ++PI) 2380 Chaining.push_back(*PI); 2381 else 2382 Chaining.push_back(VD); 2383 2384 assert(Chaining.size() >= 2); 2385 NamedDecl **NamedChain = 2386 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 2387 for (unsigned i = 0; i < Chaining.size(); i++) 2388 NamedChain[i] = Chaining[i]; 2389 2390 IndirectFieldDecl* IndirectField = 2391 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 2392 VD->getIdentifier(), VD->getType(), 2393 NamedChain, Chaining.size()); 2394 2395 IndirectField->setAccess(AS); 2396 IndirectField->setImplicit(); 2397 SemaRef.PushOnScopeChains(IndirectField, S); 2398 2399 // That includes picking up the appropriate access specifier. 2400 if (AS != AS_none) IndirectField->setAccess(AS); 2401 2402 Chaining.resize(OldChainingSize); 2403 } 2404 } 2405 } 2406 2407 return Invalid; 2408} 2409 2410/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 2411/// a VarDecl::StorageClass. Any error reporting is up to the caller: 2412/// illegal input values are mapped to SC_None. 2413static StorageClass 2414StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2415 switch (StorageClassSpec) { 2416 case DeclSpec::SCS_unspecified: return SC_None; 2417 case DeclSpec::SCS_extern: return SC_Extern; 2418 case DeclSpec::SCS_static: return SC_Static; 2419 case DeclSpec::SCS_auto: return SC_Auto; 2420 case DeclSpec::SCS_register: return SC_Register; 2421 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2422 // Illegal SCSs map to None: error reporting is up to the caller. 2423 case DeclSpec::SCS_mutable: // Fall through. 2424 case DeclSpec::SCS_typedef: return SC_None; 2425 } 2426 llvm_unreachable("unknown storage class specifier"); 2427} 2428 2429/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 2430/// a StorageClass. Any error reporting is up to the caller: 2431/// illegal input values are mapped to SC_None. 2432static StorageClass 2433StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2434 switch (StorageClassSpec) { 2435 case DeclSpec::SCS_unspecified: return SC_None; 2436 case DeclSpec::SCS_extern: return SC_Extern; 2437 case DeclSpec::SCS_static: return SC_Static; 2438 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2439 // Illegal SCSs map to None: error reporting is up to the caller. 2440 case DeclSpec::SCS_auto: // Fall through. 2441 case DeclSpec::SCS_mutable: // Fall through. 2442 case DeclSpec::SCS_register: // Fall through. 2443 case DeclSpec::SCS_typedef: return SC_None; 2444 } 2445 llvm_unreachable("unknown storage class specifier"); 2446} 2447 2448/// BuildAnonymousStructOrUnion - Handle the declaration of an 2449/// anonymous structure or union. Anonymous unions are a C++ feature 2450/// (C++ [class.union]) and a GNU C extension; anonymous structures 2451/// are a GNU C and GNU C++ extension. 2452Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 2453 AccessSpecifier AS, 2454 RecordDecl *Record) { 2455 DeclContext *Owner = Record->getDeclContext(); 2456 2457 // Diagnose whether this anonymous struct/union is an extension. 2458 if (Record->isUnion() && !getLangOptions().CPlusPlus) 2459 Diag(Record->getLocation(), diag::ext_anonymous_union); 2460 else if (!Record->isUnion()) 2461 Diag(Record->getLocation(), diag::ext_anonymous_struct); 2462 2463 // C and C++ require different kinds of checks for anonymous 2464 // structs/unions. 2465 bool Invalid = false; 2466 if (getLangOptions().CPlusPlus) { 2467 const char* PrevSpec = 0; 2468 unsigned DiagID; 2469 // C++ [class.union]p3: 2470 // Anonymous unions declared in a named namespace or in the 2471 // global namespace shall be declared static. 2472 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 2473 (isa<TranslationUnitDecl>(Owner) || 2474 (isa<NamespaceDecl>(Owner) && 2475 cast<NamespaceDecl>(Owner)->getDeclName()))) { 2476 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 2477 Invalid = true; 2478 2479 // Recover by adding 'static'. 2480 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 2481 PrevSpec, DiagID, getLangOptions()); 2482 } 2483 // C++ [class.union]p3: 2484 // A storage class is not allowed in a declaration of an 2485 // anonymous union in a class scope. 2486 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 2487 isa<RecordDecl>(Owner)) { 2488 Diag(DS.getStorageClassSpecLoc(), 2489 diag::err_anonymous_union_with_storage_spec); 2490 Invalid = true; 2491 2492 // Recover by removing the storage specifier. 2493 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 2494 PrevSpec, DiagID, getLangOptions()); 2495 } 2496 2497 // C++ [class.union]p2: 2498 // The member-specification of an anonymous union shall only 2499 // define non-static data members. [Note: nested types and 2500 // functions cannot be declared within an anonymous union. ] 2501 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 2502 MemEnd = Record->decls_end(); 2503 Mem != MemEnd; ++Mem) { 2504 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 2505 // C++ [class.union]p3: 2506 // An anonymous union shall not have private or protected 2507 // members (clause 11). 2508 assert(FD->getAccess() != AS_none); 2509 if (FD->getAccess() != AS_public) { 2510 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 2511 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 2512 Invalid = true; 2513 } 2514 2515 if (CheckNontrivialField(FD)) 2516 Invalid = true; 2517 } else if ((*Mem)->isImplicit()) { 2518 // Any implicit members are fine. 2519 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 2520 // This is a type that showed up in an 2521 // elaborated-type-specifier inside the anonymous struct or 2522 // union, but which actually declares a type outside of the 2523 // anonymous struct or union. It's okay. 2524 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 2525 if (!MemRecord->isAnonymousStructOrUnion() && 2526 MemRecord->getDeclName()) { 2527 // Visual C++ allows type definition in anonymous struct or union. 2528 if (getLangOptions().Microsoft) 2529 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 2530 << (int)Record->isUnion(); 2531 else { 2532 // This is a nested type declaration. 2533 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 2534 << (int)Record->isUnion(); 2535 Invalid = true; 2536 } 2537 } 2538 } else if (isa<AccessSpecDecl>(*Mem)) { 2539 // Any access specifier is fine. 2540 } else { 2541 // We have something that isn't a non-static data 2542 // member. Complain about it. 2543 unsigned DK = diag::err_anonymous_record_bad_member; 2544 if (isa<TypeDecl>(*Mem)) 2545 DK = diag::err_anonymous_record_with_type; 2546 else if (isa<FunctionDecl>(*Mem)) 2547 DK = diag::err_anonymous_record_with_function; 2548 else if (isa<VarDecl>(*Mem)) 2549 DK = diag::err_anonymous_record_with_static; 2550 2551 // Visual C++ allows type definition in anonymous struct or union. 2552 if (getLangOptions().Microsoft && 2553 DK == diag::err_anonymous_record_with_type) 2554 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 2555 << (int)Record->isUnion(); 2556 else { 2557 Diag((*Mem)->getLocation(), DK) 2558 << (int)Record->isUnion(); 2559 Invalid = true; 2560 } 2561 } 2562 } 2563 } 2564 2565 if (!Record->isUnion() && !Owner->isRecord()) { 2566 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 2567 << (int)getLangOptions().CPlusPlus; 2568 Invalid = true; 2569 } 2570 2571 // Mock up a declarator. 2572 Declarator Dc(DS, Declarator::TypeNameContext); 2573 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2574 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 2575 2576 // Create a declaration for this anonymous struct/union. 2577 NamedDecl *Anon = 0; 2578 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2579 Anon = FieldDecl::Create(Context, OwningClass, 2580 DS.getSourceRange().getBegin(), 2581 Record->getLocation(), 2582 /*IdentifierInfo=*/0, 2583 Context.getTypeDeclType(Record), 2584 TInfo, 2585 /*BitWidth=*/0, /*Mutable=*/false); 2586 Anon->setAccess(AS); 2587 if (getLangOptions().CPlusPlus) 2588 FieldCollector->Add(cast<FieldDecl>(Anon)); 2589 } else { 2590 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 2591 assert(SCSpec != DeclSpec::SCS_typedef && 2592 "Parser allowed 'typedef' as storage class VarDecl."); 2593 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2594 if (SCSpec == DeclSpec::SCS_mutable) { 2595 // mutable can only appear on non-static class members, so it's always 2596 // an error here 2597 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2598 Invalid = true; 2599 SC = SC_None; 2600 } 2601 SCSpec = DS.getStorageClassSpecAsWritten(); 2602 VarDecl::StorageClass SCAsWritten 2603 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2604 2605 Anon = VarDecl::Create(Context, Owner, 2606 DS.getSourceRange().getBegin(), 2607 Record->getLocation(), /*IdentifierInfo=*/0, 2608 Context.getTypeDeclType(Record), 2609 TInfo, SC, SCAsWritten); 2610 } 2611 Anon->setImplicit(); 2612 2613 // Add the anonymous struct/union object to the current 2614 // context. We'll be referencing this object when we refer to one of 2615 // its members. 2616 Owner->addDecl(Anon); 2617 2618 // Inject the members of the anonymous struct/union into the owning 2619 // context and into the identifier resolver chain for name lookup 2620 // purposes. 2621 llvm::SmallVector<NamedDecl*, 2> Chain; 2622 Chain.push_back(Anon); 2623 2624 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 2625 Chain, false)) 2626 Invalid = true; 2627 2628 // Mark this as an anonymous struct/union type. Note that we do not 2629 // do this until after we have already checked and injected the 2630 // members of this anonymous struct/union type, because otherwise 2631 // the members could be injected twice: once by DeclContext when it 2632 // builds its lookup table, and once by 2633 // InjectAnonymousStructOrUnionMembers. 2634 Record->setAnonymousStructOrUnion(true); 2635 2636 if (Invalid) 2637 Anon->setInvalidDecl(); 2638 2639 return Anon; 2640} 2641 2642/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 2643/// Microsoft C anonymous structure. 2644/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 2645/// Example: 2646/// 2647/// struct A { int a; }; 2648/// struct B { struct A; int b; }; 2649/// 2650/// void foo() { 2651/// B var; 2652/// var.a = 3; 2653/// } 2654/// 2655Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 2656 RecordDecl *Record) { 2657 2658 // If there is no Record, get the record via the typedef. 2659 if (!Record) 2660 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 2661 2662 // Mock up a declarator. 2663 Declarator Dc(DS, Declarator::TypeNameContext); 2664 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2665 assert(TInfo && "couldn't build declarator info for anonymous struct"); 2666 2667 // Create a declaration for this anonymous struct. 2668 NamedDecl* Anon = FieldDecl::Create(Context, 2669 cast<RecordDecl>(CurContext), 2670 DS.getSourceRange().getBegin(), 2671 DS.getSourceRange().getBegin(), 2672 /*IdentifierInfo=*/0, 2673 Context.getTypeDeclType(Record), 2674 TInfo, 2675 /*BitWidth=*/0, /*Mutable=*/false); 2676 Anon->setImplicit(); 2677 2678 // Add the anonymous struct object to the current context. 2679 CurContext->addDecl(Anon); 2680 2681 // Inject the members of the anonymous struct into the current 2682 // context and into the identifier resolver chain for name lookup 2683 // purposes. 2684 llvm::SmallVector<NamedDecl*, 2> Chain; 2685 Chain.push_back(Anon); 2686 2687 if (InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 2688 Record->getDefinition(), 2689 AS_none, Chain, true)) 2690 Anon->setInvalidDecl(); 2691 2692 return Anon; 2693} 2694 2695/// GetNameForDeclarator - Determine the full declaration name for the 2696/// given Declarator. 2697DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2698 return GetNameFromUnqualifiedId(D.getName()); 2699} 2700 2701/// \brief Retrieves the declaration name from a parsed unqualified-id. 2702DeclarationNameInfo 2703Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2704 DeclarationNameInfo NameInfo; 2705 NameInfo.setLoc(Name.StartLocation); 2706 2707 switch (Name.getKind()) { 2708 2709 case UnqualifiedId::IK_Identifier: 2710 NameInfo.setName(Name.Identifier); 2711 NameInfo.setLoc(Name.StartLocation); 2712 return NameInfo; 2713 2714 case UnqualifiedId::IK_OperatorFunctionId: 2715 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2716 Name.OperatorFunctionId.Operator)); 2717 NameInfo.setLoc(Name.StartLocation); 2718 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2719 = Name.OperatorFunctionId.SymbolLocations[0]; 2720 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2721 = Name.EndLocation.getRawEncoding(); 2722 return NameInfo; 2723 2724 case UnqualifiedId::IK_LiteralOperatorId: 2725 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2726 Name.Identifier)); 2727 NameInfo.setLoc(Name.StartLocation); 2728 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2729 return NameInfo; 2730 2731 case UnqualifiedId::IK_ConversionFunctionId: { 2732 TypeSourceInfo *TInfo; 2733 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2734 if (Ty.isNull()) 2735 return DeclarationNameInfo(); 2736 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2737 Context.getCanonicalType(Ty))); 2738 NameInfo.setLoc(Name.StartLocation); 2739 NameInfo.setNamedTypeInfo(TInfo); 2740 return NameInfo; 2741 } 2742 2743 case UnqualifiedId::IK_ConstructorName: { 2744 TypeSourceInfo *TInfo; 2745 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2746 if (Ty.isNull()) 2747 return DeclarationNameInfo(); 2748 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2749 Context.getCanonicalType(Ty))); 2750 NameInfo.setLoc(Name.StartLocation); 2751 NameInfo.setNamedTypeInfo(TInfo); 2752 return NameInfo; 2753 } 2754 2755 case UnqualifiedId::IK_ConstructorTemplateId: { 2756 // In well-formed code, we can only have a constructor 2757 // template-id that refers to the current context, so go there 2758 // to find the actual type being constructed. 2759 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2760 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2761 return DeclarationNameInfo(); 2762 2763 // Determine the type of the class being constructed. 2764 QualType CurClassType = Context.getTypeDeclType(CurClass); 2765 2766 // FIXME: Check two things: that the template-id names the same type as 2767 // CurClassType, and that the template-id does not occur when the name 2768 // was qualified. 2769 2770 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2771 Context.getCanonicalType(CurClassType))); 2772 NameInfo.setLoc(Name.StartLocation); 2773 // FIXME: should we retrieve TypeSourceInfo? 2774 NameInfo.setNamedTypeInfo(0); 2775 return NameInfo; 2776 } 2777 2778 case UnqualifiedId::IK_DestructorName: { 2779 TypeSourceInfo *TInfo; 2780 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2781 if (Ty.isNull()) 2782 return DeclarationNameInfo(); 2783 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2784 Context.getCanonicalType(Ty))); 2785 NameInfo.setLoc(Name.StartLocation); 2786 NameInfo.setNamedTypeInfo(TInfo); 2787 return NameInfo; 2788 } 2789 2790 case UnqualifiedId::IK_TemplateId: { 2791 TemplateName TName = Name.TemplateId->Template.get(); 2792 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2793 return Context.getNameForTemplate(TName, TNameLoc); 2794 } 2795 2796 } // switch (Name.getKind()) 2797 2798 assert(false && "Unknown name kind"); 2799 return DeclarationNameInfo(); 2800} 2801 2802/// isNearlyMatchingFunction - Determine whether the C++ functions 2803/// Declaration and Definition are "nearly" matching. This heuristic 2804/// is used to improve diagnostics in the case where an out-of-line 2805/// function definition doesn't match any declaration within 2806/// the class or namespace. 2807static bool isNearlyMatchingFunction(ASTContext &Context, 2808 FunctionDecl *Declaration, 2809 FunctionDecl *Definition) { 2810 if (Declaration->param_size() != Definition->param_size()) 2811 return false; 2812 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2813 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2814 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2815 2816 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2817 DefParamTy.getNonReferenceType())) 2818 return false; 2819 } 2820 2821 return true; 2822} 2823 2824/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2825/// declarator needs to be rebuilt in the current instantiation. 2826/// Any bits of declarator which appear before the name are valid for 2827/// consideration here. That's specifically the type in the decl spec 2828/// and the base type in any member-pointer chunks. 2829static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2830 DeclarationName Name) { 2831 // The types we specifically need to rebuild are: 2832 // - typenames, typeofs, and decltypes 2833 // - types which will become injected class names 2834 // Of course, we also need to rebuild any type referencing such a 2835 // type. It's safest to just say "dependent", but we call out a 2836 // few cases here. 2837 2838 DeclSpec &DS = D.getMutableDeclSpec(); 2839 switch (DS.getTypeSpecType()) { 2840 case DeclSpec::TST_typename: 2841 case DeclSpec::TST_typeofType: 2842 case DeclSpec::TST_decltype: { 2843 // Grab the type from the parser. 2844 TypeSourceInfo *TSI = 0; 2845 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2846 if (T.isNull() || !T->isDependentType()) break; 2847 2848 // Make sure there's a type source info. This isn't really much 2849 // of a waste; most dependent types should have type source info 2850 // attached already. 2851 if (!TSI) 2852 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2853 2854 // Rebuild the type in the current instantiation. 2855 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2856 if (!TSI) return true; 2857 2858 // Store the new type back in the decl spec. 2859 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2860 DS.UpdateTypeRep(LocType); 2861 break; 2862 } 2863 2864 case DeclSpec::TST_typeofExpr: { 2865 Expr *E = DS.getRepAsExpr(); 2866 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2867 if (Result.isInvalid()) return true; 2868 DS.UpdateExprRep(Result.get()); 2869 break; 2870 } 2871 2872 default: 2873 // Nothing to do for these decl specs. 2874 break; 2875 } 2876 2877 // It doesn't matter what order we do this in. 2878 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2879 DeclaratorChunk &Chunk = D.getTypeObject(I); 2880 2881 // The only type information in the declarator which can come 2882 // before the declaration name is the base type of a member 2883 // pointer. 2884 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2885 continue; 2886 2887 // Rebuild the scope specifier in-place. 2888 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2889 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2890 return true; 2891 } 2892 2893 return false; 2894} 2895 2896Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2897 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2898} 2899 2900/// DiagnoseClassNameShadow - Implement C++ [class.mem]p13: 2901/// If T is the name of a class, then each of the following shall have a 2902/// name different from T: 2903/// - every static data member of class T; 2904/// - every member function of class T 2905/// - every member of class T that is itself a type; 2906/// \returns true if the declaration name violates these rules. 2907bool Sema::DiagnoseClassNameShadow(DeclContext *DC, 2908 DeclarationNameInfo NameInfo) { 2909 DeclarationName Name = NameInfo.getName(); 2910 2911 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2912 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2913 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name; 2914 return true; 2915 } 2916 2917 return false; 2918} 2919 2920Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2921 MultiTemplateParamsArg TemplateParamLists, 2922 bool IsFunctionDefinition, 2923 SourceLocation DefLoc) { 2924 // TODO: consider using NameInfo for diagnostic. 2925 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2926 DeclarationName Name = NameInfo.getName(); 2927 2928 // All of these full declarators require an identifier. If it doesn't have 2929 // one, the ParsedFreeStandingDeclSpec action should be used. 2930 if (!Name) { 2931 if (!D.isInvalidType()) // Reject this if we think it is valid. 2932 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2933 diag::err_declarator_need_ident) 2934 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2935 return 0; 2936 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 2937 return 0; 2938 2939 // The scope passed in may not be a decl scope. Zip up the scope tree until 2940 // we find one that is. 2941 while ((S->getFlags() & Scope::DeclScope) == 0 || 2942 (S->getFlags() & Scope::TemplateParamScope) != 0) 2943 S = S->getParent(); 2944 2945 DeclContext *DC = CurContext; 2946 if (D.getCXXScopeSpec().isInvalid()) 2947 D.setInvalidType(); 2948 else if (D.getCXXScopeSpec().isSet()) { 2949 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 2950 UPPC_DeclarationQualifier)) 2951 return 0; 2952 2953 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2954 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2955 if (!DC) { 2956 // If we could not compute the declaration context, it's because the 2957 // declaration context is dependent but does not refer to a class, 2958 // class template, or class template partial specialization. Complain 2959 // and return early, to avoid the coming semantic disaster. 2960 Diag(D.getIdentifierLoc(), 2961 diag::err_template_qualified_declarator_no_match) 2962 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2963 << D.getCXXScopeSpec().getRange(); 2964 return 0; 2965 } 2966 bool IsDependentContext = DC->isDependentContext(); 2967 2968 if (!IsDependentContext && 2969 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2970 return 0; 2971 2972 if (isa<CXXRecordDecl>(DC)) { 2973 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2974 Diag(D.getIdentifierLoc(), 2975 diag::err_member_def_undefined_record) 2976 << Name << DC << D.getCXXScopeSpec().getRange(); 2977 D.setInvalidType(); 2978 } else if (isa<CXXRecordDecl>(CurContext) && 2979 !D.getDeclSpec().isFriendSpecified()) { 2980 // The user provided a superfluous scope specifier inside a class 2981 // definition: 2982 // 2983 // class X { 2984 // void X::f(); 2985 // }; 2986 if (CurContext->Equals(DC)) 2987 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2988 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2989 else 2990 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2991 << Name << D.getCXXScopeSpec().getRange(); 2992 2993 // Pretend that this qualifier was not here. 2994 D.getCXXScopeSpec().clear(); 2995 } 2996 } 2997 2998 // Check whether we need to rebuild the type of the given 2999 // declaration in the current instantiation. 3000 if (EnteringContext && IsDependentContext && 3001 TemplateParamLists.size() != 0) { 3002 ContextRAII SavedContext(*this, DC); 3003 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 3004 D.setInvalidType(); 3005 } 3006 } 3007 3008 if (DiagnoseClassNameShadow(DC, NameInfo)) 3009 // If this is a typedef, we'll end up spewing multiple diagnostics. 3010 // Just return early; it's safer. 3011 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 3012 return 0; 3013 3014 NamedDecl *New; 3015 3016 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 3017 QualType R = TInfo->getType(); 3018 3019 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 3020 UPPC_DeclarationType)) 3021 D.setInvalidType(); 3022 3023 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 3024 ForRedeclaration); 3025 3026 // See if this is a redefinition of a variable in the same scope. 3027 if (!D.getCXXScopeSpec().isSet()) { 3028 bool IsLinkageLookup = false; 3029 3030 // If the declaration we're planning to build will be a function 3031 // or object with linkage, then look for another declaration with 3032 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 3033 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 3034 /* Do nothing*/; 3035 else if (R->isFunctionType()) { 3036 if (CurContext->isFunctionOrMethod() || 3037 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 3038 IsLinkageLookup = true; 3039 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 3040 IsLinkageLookup = true; 3041 else if (CurContext->getRedeclContext()->isTranslationUnit() && 3042 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 3043 IsLinkageLookup = true; 3044 3045 if (IsLinkageLookup) 3046 Previous.clear(LookupRedeclarationWithLinkage); 3047 3048 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 3049 } else { // Something like "int foo::x;" 3050 LookupQualifiedName(Previous, DC); 3051 3052 // Don't consider using declarations as previous declarations for 3053 // out-of-line members. 3054 RemoveUsingDecls(Previous); 3055 3056 // C++ 7.3.1.2p2: 3057 // Members (including explicit specializations of templates) of a named 3058 // namespace can also be defined outside that namespace by explicit 3059 // qualification of the name being defined, provided that the entity being 3060 // defined was already declared in the namespace and the definition appears 3061 // after the point of declaration in a namespace that encloses the 3062 // declarations namespace. 3063 // 3064 // Note that we only check the context at this point. We don't yet 3065 // have enough information to make sure that PrevDecl is actually 3066 // the declaration we want to match. For example, given: 3067 // 3068 // class X { 3069 // void f(); 3070 // void f(float); 3071 // }; 3072 // 3073 // void X::f(int) { } // ill-formed 3074 // 3075 // In this case, PrevDecl will point to the overload set 3076 // containing the two f's declared in X, but neither of them 3077 // matches. 3078 3079 // First check whether we named the global scope. 3080 if (isa<TranslationUnitDecl>(DC)) { 3081 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 3082 << Name << D.getCXXScopeSpec().getRange(); 3083 } else { 3084 DeclContext *Cur = CurContext; 3085 while (isa<LinkageSpecDecl>(Cur)) 3086 Cur = Cur->getParent(); 3087 if (!Cur->Encloses(DC)) { 3088 // The qualifying scope doesn't enclose the original declaration. 3089 // Emit diagnostic based on current scope. 3090 SourceLocation L = D.getIdentifierLoc(); 3091 SourceRange R = D.getCXXScopeSpec().getRange(); 3092 if (isa<FunctionDecl>(Cur)) 3093 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 3094 else 3095 Diag(L, diag::err_invalid_declarator_scope) 3096 << Name << cast<NamedDecl>(DC) << R; 3097 D.setInvalidType(); 3098 } 3099 } 3100 } 3101 3102 if (Previous.isSingleResult() && 3103 Previous.getFoundDecl()->isTemplateParameter()) { 3104 // Maybe we will complain about the shadowed template parameter. 3105 if (!D.isInvalidType()) 3106 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 3107 Previous.getFoundDecl())) 3108 D.setInvalidType(); 3109 3110 // Just pretend that we didn't see the previous declaration. 3111 Previous.clear(); 3112 } 3113 3114 // In C++, the previous declaration we find might be a tag type 3115 // (class or enum). In this case, the new declaration will hide the 3116 // tag type. Note that this does does not apply if we're declaring a 3117 // typedef (C++ [dcl.typedef]p4). 3118 if (Previous.isSingleTagDecl() && 3119 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 3120 Previous.clear(); 3121 3122 bool Redeclaration = false; 3123 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 3124 if (DefLoc.isValid()) 3125 Diag(DefLoc, diag::err_default_special_members); 3126 3127 if (TemplateParamLists.size()) { 3128 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 3129 return 0; 3130 } 3131 3132 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 3133 } else if (R->isFunctionType()) { 3134 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 3135 move(TemplateParamLists), 3136 IsFunctionDefinition, Redeclaration, DefLoc); 3137 } else { 3138 assert(!DefLoc.isValid() && "We should have caught this in a caller"); 3139 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 3140 move(TemplateParamLists), 3141 Redeclaration); 3142 } 3143 3144 if (New == 0) 3145 return 0; 3146 3147 // If this has an identifier and is not an invalid redeclaration or 3148 // function template specialization, add it to the scope stack. 3149 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 3150 PushOnScopeChains(New, S); 3151 3152 return New; 3153} 3154 3155/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3156/// types into constant array types in certain situations which would otherwise 3157/// be errors (for GCC compatibility). 3158static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3159 ASTContext &Context, 3160 bool &SizeIsNegative, 3161 llvm::APSInt &Oversized) { 3162 // This method tries to turn a variable array into a constant 3163 // array even when the size isn't an ICE. This is necessary 3164 // for compatibility with code that depends on gcc's buggy 3165 // constant expression folding, like struct {char x[(int)(char*)2];} 3166 SizeIsNegative = false; 3167 Oversized = 0; 3168 3169 if (T->isDependentType()) 3170 return QualType(); 3171 3172 QualifierCollector Qs; 3173 const Type *Ty = Qs.strip(T); 3174 3175 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 3176 QualType Pointee = PTy->getPointeeType(); 3177 QualType FixedType = 3178 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 3179 Oversized); 3180 if (FixedType.isNull()) return FixedType; 3181 FixedType = Context.getPointerType(FixedType); 3182 return Qs.apply(Context, FixedType); 3183 } 3184 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 3185 QualType Inner = PTy->getInnerType(); 3186 QualType FixedType = 3187 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 3188 Oversized); 3189 if (FixedType.isNull()) return FixedType; 3190 FixedType = Context.getParenType(FixedType); 3191 return Qs.apply(Context, FixedType); 3192 } 3193 3194 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3195 if (!VLATy) 3196 return QualType(); 3197 // FIXME: We should probably handle this case 3198 if (VLATy->getElementType()->isVariablyModifiedType()) 3199 return QualType(); 3200 3201 Expr::EvalResult EvalResult; 3202 if (!VLATy->getSizeExpr() || 3203 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 3204 !EvalResult.Val.isInt()) 3205 return QualType(); 3206 3207 // Check whether the array size is negative. 3208 llvm::APSInt &Res = EvalResult.Val.getInt(); 3209 if (Res.isSigned() && Res.isNegative()) { 3210 SizeIsNegative = true; 3211 return QualType(); 3212 } 3213 3214 // Check whether the array is too large to be addressed. 3215 unsigned ActiveSizeBits 3216 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 3217 Res); 3218 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 3219 Oversized = Res; 3220 return QualType(); 3221 } 3222 3223 return Context.getConstantArrayType(VLATy->getElementType(), 3224 Res, ArrayType::Normal, 0); 3225} 3226 3227/// \brief Register the given locally-scoped external C declaration so 3228/// that it can be found later for redeclarations 3229void 3230Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 3231 const LookupResult &Previous, 3232 Scope *S) { 3233 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 3234 "Decl is not a locally-scoped decl!"); 3235 // Note that we have a locally-scoped external with this name. 3236 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 3237 3238 if (!Previous.isSingleResult()) 3239 return; 3240 3241 NamedDecl *PrevDecl = Previous.getFoundDecl(); 3242 3243 // If there was a previous declaration of this variable, it may be 3244 // in our identifier chain. Update the identifier chain with the new 3245 // declaration. 3246 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 3247 // The previous declaration was found on the identifer resolver 3248 // chain, so remove it from its scope. 3249 while (S && !S->isDeclScope(PrevDecl)) 3250 S = S->getParent(); 3251 3252 if (S) 3253 S->RemoveDecl(PrevDecl); 3254 } 3255} 3256 3257/// \brief Diagnose function specifiers on a declaration of an identifier that 3258/// does not identify a function. 3259void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 3260 // FIXME: We should probably indicate the identifier in question to avoid 3261 // confusion for constructs like "inline int a(), b;" 3262 if (D.getDeclSpec().isInlineSpecified()) 3263 Diag(D.getDeclSpec().getInlineSpecLoc(), 3264 diag::err_inline_non_function); 3265 3266 if (D.getDeclSpec().isVirtualSpecified()) 3267 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3268 diag::err_virtual_non_function); 3269 3270 if (D.getDeclSpec().isExplicitSpecified()) 3271 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3272 diag::err_explicit_non_function); 3273} 3274 3275NamedDecl* 3276Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3277 QualType R, TypeSourceInfo *TInfo, 3278 LookupResult &Previous, bool &Redeclaration) { 3279 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 3280 if (D.getCXXScopeSpec().isSet()) { 3281 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 3282 << D.getCXXScopeSpec().getRange(); 3283 D.setInvalidType(); 3284 // Pretend we didn't see the scope specifier. 3285 DC = CurContext; 3286 Previous.clear(); 3287 } 3288 3289 if (getLangOptions().CPlusPlus) { 3290 // Check that there are no default arguments (C++ only). 3291 CheckExtraCXXDefaultArguments(D); 3292 } 3293 3294 DiagnoseFunctionSpecifiers(D); 3295 3296 if (D.getDeclSpec().isThreadSpecified()) 3297 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3298 3299 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 3300 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 3301 << D.getName().getSourceRange(); 3302 return 0; 3303 } 3304 3305 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 3306 if (!NewTD) return 0; 3307 3308 // Handle attributes prior to checking for duplicates in MergeVarDecl 3309 ProcessDeclAttributes(S, NewTD, D); 3310 3311 CheckTypedefForVariablyModifiedType(S, NewTD); 3312 3313 return ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration); 3314} 3315 3316void 3317Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) { 3318 // C99 6.7.7p2: If a typedef name specifies a variably modified type 3319 // then it shall have block scope. 3320 // Note that variably modified types must be fixed before merging the decl so 3321 // that redeclarations will match. 3322 QualType T = NewTD->getUnderlyingType(); 3323 if (T->isVariablyModifiedType()) { 3324 getCurFunction()->setHasBranchProtectedScope(); 3325 3326 if (S->getFnParent() == 0) { 3327 bool SizeIsNegative; 3328 llvm::APSInt Oversized; 3329 QualType FixedTy = 3330 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3331 Oversized); 3332 if (!FixedTy.isNull()) { 3333 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size); 3334 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 3335 } else { 3336 if (SizeIsNegative) 3337 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size); 3338 else if (T->isVariableArrayType()) 3339 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope); 3340 else if (Oversized.getBoolValue()) 3341 Diag(NewTD->getLocation(), diag::err_array_too_large) << Oversized.toString(10); 3342 else 3343 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope); 3344 NewTD->setInvalidDecl(); 3345 } 3346 } 3347 } 3348} 3349 3350 3351/// ActOnTypedefNameDecl - Perform semantic checking for a declaration which 3352/// declares a typedef-name, either using the 'typedef' type specifier or via 3353/// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'. 3354NamedDecl* 3355Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD, 3356 LookupResult &Previous, bool &Redeclaration) { 3357 // Merge the decl with the existing one if appropriate. If the decl is 3358 // in an outer scope, it isn't the same thing. 3359 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/ false, 3360 /*ExplicitInstantiationOrSpecialization=*/false); 3361 if (!Previous.empty()) { 3362 Redeclaration = true; 3363 MergeTypedefNameDecl(NewTD, Previous); 3364 } 3365 3366 // If this is the C FILE type, notify the AST context. 3367 if (IdentifierInfo *II = NewTD->getIdentifier()) 3368 if (!NewTD->isInvalidDecl() && 3369 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 3370 if (II->isStr("FILE")) 3371 Context.setFILEDecl(NewTD); 3372 else if (II->isStr("jmp_buf")) 3373 Context.setjmp_bufDecl(NewTD); 3374 else if (II->isStr("sigjmp_buf")) 3375 Context.setsigjmp_bufDecl(NewTD); 3376 else if (II->isStr("__builtin_va_list")) 3377 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 3378 } 3379 3380 return NewTD; 3381} 3382 3383/// \brief Determines whether the given declaration is an out-of-scope 3384/// previous declaration. 3385/// 3386/// This routine should be invoked when name lookup has found a 3387/// previous declaration (PrevDecl) that is not in the scope where a 3388/// new declaration by the same name is being introduced. If the new 3389/// declaration occurs in a local scope, previous declarations with 3390/// linkage may still be considered previous declarations (C99 3391/// 6.2.2p4-5, C++ [basic.link]p6). 3392/// 3393/// \param PrevDecl the previous declaration found by name 3394/// lookup 3395/// 3396/// \param DC the context in which the new declaration is being 3397/// declared. 3398/// 3399/// \returns true if PrevDecl is an out-of-scope previous declaration 3400/// for a new delcaration with the same name. 3401static bool 3402isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 3403 ASTContext &Context) { 3404 if (!PrevDecl) 3405 return false; 3406 3407 if (!PrevDecl->hasLinkage()) 3408 return false; 3409 3410 if (Context.getLangOptions().CPlusPlus) { 3411 // C++ [basic.link]p6: 3412 // If there is a visible declaration of an entity with linkage 3413 // having the same name and type, ignoring entities declared 3414 // outside the innermost enclosing namespace scope, the block 3415 // scope declaration declares that same entity and receives the 3416 // linkage of the previous declaration. 3417 DeclContext *OuterContext = DC->getRedeclContext(); 3418 if (!OuterContext->isFunctionOrMethod()) 3419 // This rule only applies to block-scope declarations. 3420 return false; 3421 3422 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 3423 if (PrevOuterContext->isRecord()) 3424 // We found a member function: ignore it. 3425 return false; 3426 3427 // Find the innermost enclosing namespace for the new and 3428 // previous declarations. 3429 OuterContext = OuterContext->getEnclosingNamespaceContext(); 3430 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 3431 3432 // The previous declaration is in a different namespace, so it 3433 // isn't the same function. 3434 if (!OuterContext->Equals(PrevOuterContext)) 3435 return false; 3436 } 3437 3438 return true; 3439} 3440 3441static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 3442 CXXScopeSpec &SS = D.getCXXScopeSpec(); 3443 if (!SS.isSet()) return; 3444 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 3445} 3446 3447NamedDecl* 3448Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 3449 QualType R, TypeSourceInfo *TInfo, 3450 LookupResult &Previous, 3451 MultiTemplateParamsArg TemplateParamLists, 3452 bool &Redeclaration) { 3453 DeclarationName Name = GetNameForDeclarator(D).getName(); 3454 3455 // Check that there are no default arguments (C++ only). 3456 if (getLangOptions().CPlusPlus) 3457 CheckExtraCXXDefaultArguments(D); 3458 3459 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 3460 assert(SCSpec != DeclSpec::SCS_typedef && 3461 "Parser allowed 'typedef' as storage class VarDecl."); 3462 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 3463 if (SCSpec == DeclSpec::SCS_mutable) { 3464 // mutable can only appear on non-static class members, so it's always 3465 // an error here 3466 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 3467 D.setInvalidType(); 3468 SC = SC_None; 3469 } 3470 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3471 VarDecl::StorageClass SCAsWritten 3472 = StorageClassSpecToVarDeclStorageClass(SCSpec); 3473 3474 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3475 if (!II) { 3476 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 3477 << Name.getAsString(); 3478 return 0; 3479 } 3480 3481 DiagnoseFunctionSpecifiers(D); 3482 3483 if (!DC->isRecord() && S->getFnParent() == 0) { 3484 // C99 6.9p2: The storage-class specifiers auto and register shall not 3485 // appear in the declaration specifiers in an external declaration. 3486 if (SC == SC_Auto || SC == SC_Register) { 3487 3488 // If this is a register variable with an asm label specified, then this 3489 // is a GNU extension. 3490 if (SC == SC_Register && D.getAsmLabel()) 3491 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 3492 else 3493 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 3494 D.setInvalidType(); 3495 } 3496 } 3497 3498 bool isExplicitSpecialization = false; 3499 VarDecl *NewVD; 3500 if (!getLangOptions().CPlusPlus) { 3501 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3502 D.getIdentifierLoc(), II, 3503 R, TInfo, SC, SCAsWritten); 3504 3505 if (D.isInvalidType()) 3506 NewVD->setInvalidDecl(); 3507 } else { 3508 if (DC->isRecord() && !CurContext->isRecord()) { 3509 // This is an out-of-line definition of a static data member. 3510 if (SC == SC_Static) { 3511 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3512 diag::err_static_out_of_line) 3513 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3514 } else if (SC == SC_None) 3515 SC = SC_Static; 3516 } 3517 if (SC == SC_Static) { 3518 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 3519 if (RD->isLocalClass()) 3520 Diag(D.getIdentifierLoc(), 3521 diag::err_static_data_member_not_allowed_in_local_class) 3522 << Name << RD->getDeclName(); 3523 3524 // C++ [class.union]p1: If a union contains a static data member, 3525 // the program is ill-formed. 3526 // 3527 // We also disallow static data members in anonymous structs. 3528 if (CurContext->isRecord() && (RD->isUnion() || !RD->getDeclName())) 3529 Diag(D.getIdentifierLoc(), 3530 diag::err_static_data_member_not_allowed_in_union_or_anon_struct) 3531 << Name << RD->isUnion(); 3532 } 3533 } 3534 3535 // Match up the template parameter lists with the scope specifier, then 3536 // determine whether we have a template or a template specialization. 3537 isExplicitSpecialization = false; 3538 bool Invalid = false; 3539 if (TemplateParameterList *TemplateParams 3540 = MatchTemplateParametersToScopeSpecifier( 3541 D.getDeclSpec().getSourceRange().getBegin(), 3542 D.getCXXScopeSpec(), 3543 TemplateParamLists.get(), 3544 TemplateParamLists.size(), 3545 /*never a friend*/ false, 3546 isExplicitSpecialization, 3547 Invalid)) { 3548 if (TemplateParams->size() > 0) { 3549 // There is no such thing as a variable template. 3550 Diag(D.getIdentifierLoc(), diag::err_template_variable) 3551 << II 3552 << SourceRange(TemplateParams->getTemplateLoc(), 3553 TemplateParams->getRAngleLoc()); 3554 return 0; 3555 } else { 3556 // There is an extraneous 'template<>' for this variable. Complain 3557 // about it, but allow the declaration of the variable. 3558 Diag(TemplateParams->getTemplateLoc(), 3559 diag::err_template_variable_noparams) 3560 << II 3561 << SourceRange(TemplateParams->getTemplateLoc(), 3562 TemplateParams->getRAngleLoc()); 3563 isExplicitSpecialization = true; 3564 } 3565 } 3566 3567 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3568 D.getIdentifierLoc(), II, 3569 R, TInfo, SC, SCAsWritten); 3570 3571 // If this decl has an auto type in need of deduction, make a note of the 3572 // Decl so we can diagnose uses of it in its own initializer. 3573 if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto && 3574 R->getContainedAutoType()) 3575 ParsingInitForAutoVars.insert(NewVD); 3576 3577 if (D.isInvalidType() || Invalid) 3578 NewVD->setInvalidDecl(); 3579 3580 SetNestedNameSpecifier(NewVD, D); 3581 3582 if (TemplateParamLists.size() > 0 && D.getCXXScopeSpec().isSet()) { 3583 NewVD->setTemplateParameterListsInfo(Context, 3584 TemplateParamLists.size(), 3585 TemplateParamLists.release()); 3586 } 3587 } 3588 3589 if (D.getDeclSpec().isThreadSpecified()) { 3590 if (NewVD->hasLocalStorage()) 3591 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 3592 else if (!Context.Target.isTLSSupported()) 3593 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 3594 else 3595 NewVD->setThreadSpecified(true); 3596 } 3597 3598 // Set the lexical context. If the declarator has a C++ scope specifier, the 3599 // lexical context will be different from the semantic context. 3600 NewVD->setLexicalDeclContext(CurContext); 3601 3602 // Handle attributes prior to checking for duplicates in MergeVarDecl 3603 ProcessDeclAttributes(S, NewVD, D); 3604 3605 // Handle GNU asm-label extension (encoded as an attribute). 3606 if (Expr *E = (Expr*)D.getAsmLabel()) { 3607 // The parser guarantees this is a string. 3608 StringLiteral *SE = cast<StringLiteral>(E); 3609 llvm::StringRef Label = SE->getString(); 3610 if (S->getFnParent() != 0) { 3611 switch (SC) { 3612 case SC_None: 3613 case SC_Auto: 3614 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 3615 break; 3616 case SC_Register: 3617 if (!Context.Target.isValidGCCRegisterName(Label)) 3618 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 3619 break; 3620 case SC_Static: 3621 case SC_Extern: 3622 case SC_PrivateExtern: 3623 break; 3624 } 3625 } 3626 3627 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 3628 Context, Label)); 3629 } 3630 3631 // Diagnose shadowed variables before filtering for scope. 3632 if (!D.getCXXScopeSpec().isSet()) 3633 CheckShadow(S, NewVD, Previous); 3634 3635 // Don't consider existing declarations that are in a different 3636 // scope and are out-of-semantic-context declarations (if the new 3637 // declaration has linkage). 3638 FilterLookupForScope(Previous, DC, S, NewVD->hasLinkage(), 3639 isExplicitSpecialization); 3640 3641 if (!getLangOptions().CPlusPlus) 3642 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3643 else { 3644 // Merge the decl with the existing one if appropriate. 3645 if (!Previous.empty()) { 3646 if (Previous.isSingleResult() && 3647 isa<FieldDecl>(Previous.getFoundDecl()) && 3648 D.getCXXScopeSpec().isSet()) { 3649 // The user tried to define a non-static data member 3650 // out-of-line (C++ [dcl.meaning]p1). 3651 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 3652 << D.getCXXScopeSpec().getRange(); 3653 Previous.clear(); 3654 NewVD->setInvalidDecl(); 3655 } 3656 } else if (D.getCXXScopeSpec().isSet()) { 3657 // No previous declaration in the qualifying scope. 3658 Diag(D.getIdentifierLoc(), diag::err_no_member) 3659 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 3660 << D.getCXXScopeSpec().getRange(); 3661 NewVD->setInvalidDecl(); 3662 } 3663 3664 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3665 3666 // This is an explicit specialization of a static data member. Check it. 3667 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 3668 CheckMemberSpecialization(NewVD, Previous)) 3669 NewVD->setInvalidDecl(); 3670 } 3671 3672 // attributes declared post-definition are currently ignored 3673 // FIXME: This should be handled in attribute merging, not 3674 // here. 3675 if (Previous.isSingleResult()) { 3676 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 3677 if (Def && (Def = Def->getDefinition()) && 3678 Def != NewVD && D.hasAttributes()) { 3679 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 3680 Diag(Def->getLocation(), diag::note_previous_definition); 3681 } 3682 } 3683 3684 // If this is a locally-scoped extern C variable, update the map of 3685 // such variables. 3686 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 3687 !NewVD->isInvalidDecl()) 3688 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 3689 3690 // If there's a #pragma GCC visibility in scope, and this isn't a class 3691 // member, set the visibility of this variable. 3692 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3693 AddPushedVisibilityAttribute(NewVD); 3694 3695 MarkUnusedFileScopedDecl(NewVD); 3696 3697 return NewVD; 3698} 3699 3700/// \brief Diagnose variable or built-in function shadowing. Implements 3701/// -Wshadow. 3702/// 3703/// This method is called whenever a VarDecl is added to a "useful" 3704/// scope. 3705/// 3706/// \param S the scope in which the shadowing name is being declared 3707/// \param R the lookup of the name 3708/// 3709void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 3710 // Return if warning is ignored. 3711 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 3712 Diagnostic::Ignored) 3713 return; 3714 3715 // Don't diagnose declarations at file scope. 3716 if (D->hasGlobalStorage()) 3717 return; 3718 3719 DeclContext *NewDC = D->getDeclContext(); 3720 3721 // Only diagnose if we're shadowing an unambiguous field or variable. 3722 if (R.getResultKind() != LookupResult::Found) 3723 return; 3724 3725 NamedDecl* ShadowedDecl = R.getFoundDecl(); 3726 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 3727 return; 3728 3729 // Fields are not shadowed by variables in C++ static methods. 3730 if (isa<FieldDecl>(ShadowedDecl)) 3731 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 3732 if (MD->isStatic()) 3733 return; 3734 3735 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 3736 if (shadowedVar->isExternC()) { 3737 // For shadowing external vars, make sure that we point to the global 3738 // declaration, not a locally scoped extern declaration. 3739 for (VarDecl::redecl_iterator 3740 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 3741 I != E; ++I) 3742 if (I->isFileVarDecl()) { 3743 ShadowedDecl = *I; 3744 break; 3745 } 3746 } 3747 3748 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 3749 3750 // Only warn about certain kinds of shadowing for class members. 3751 if (NewDC && NewDC->isRecord()) { 3752 // In particular, don't warn about shadowing non-class members. 3753 if (!OldDC->isRecord()) 3754 return; 3755 3756 // TODO: should we warn about static data members shadowing 3757 // static data members from base classes? 3758 3759 // TODO: don't diagnose for inaccessible shadowed members. 3760 // This is hard to do perfectly because we might friend the 3761 // shadowing context, but that's just a false negative. 3762 } 3763 3764 // Determine what kind of declaration we're shadowing. 3765 unsigned Kind; 3766 if (isa<RecordDecl>(OldDC)) { 3767 if (isa<FieldDecl>(ShadowedDecl)) 3768 Kind = 3; // field 3769 else 3770 Kind = 2; // static data member 3771 } else if (OldDC->isFileContext()) 3772 Kind = 1; // global 3773 else 3774 Kind = 0; // local 3775 3776 DeclarationName Name = R.getLookupName(); 3777 3778 // Emit warning and note. 3779 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 3780 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 3781} 3782 3783/// \brief Check -Wshadow without the advantage of a previous lookup. 3784void Sema::CheckShadow(Scope *S, VarDecl *D) { 3785 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 3786 Diagnostic::Ignored) 3787 return; 3788 3789 LookupResult R(*this, D->getDeclName(), D->getLocation(), 3790 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3791 LookupName(R, S); 3792 CheckShadow(S, D, R); 3793} 3794 3795/// \brief Perform semantic checking on a newly-created variable 3796/// declaration. 3797/// 3798/// This routine performs all of the type-checking required for a 3799/// variable declaration once it has been built. It is used both to 3800/// check variables after they have been parsed and their declarators 3801/// have been translated into a declaration, and to check variables 3802/// that have been instantiated from a template. 3803/// 3804/// Sets NewVD->isInvalidDecl() if an error was encountered. 3805void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3806 LookupResult &Previous, 3807 bool &Redeclaration) { 3808 // If the decl is already known invalid, don't check it. 3809 if (NewVD->isInvalidDecl()) 3810 return; 3811 3812 QualType T = NewVD->getType(); 3813 3814 if (T->isObjCObjectType()) { 3815 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3816 return NewVD->setInvalidDecl(); 3817 } 3818 3819 // Emit an error if an address space was applied to decl with local storage. 3820 // This includes arrays of objects with address space qualifiers, but not 3821 // automatic variables that point to other address spaces. 3822 // ISO/IEC TR 18037 S5.1.2 3823 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3824 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3825 return NewVD->setInvalidDecl(); 3826 } 3827 3828 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3829 && !NewVD->hasAttr<BlocksAttr>()) 3830 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3831 3832 bool isVM = T->isVariablyModifiedType(); 3833 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3834 NewVD->hasAttr<BlocksAttr>()) 3835 getCurFunction()->setHasBranchProtectedScope(); 3836 3837 if ((isVM && NewVD->hasLinkage()) || 3838 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3839 bool SizeIsNegative; 3840 llvm::APSInt Oversized; 3841 QualType FixedTy = 3842 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3843 Oversized); 3844 3845 if (FixedTy.isNull() && T->isVariableArrayType()) { 3846 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3847 // FIXME: This won't give the correct result for 3848 // int a[10][n]; 3849 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3850 3851 if (NewVD->isFileVarDecl()) 3852 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3853 << SizeRange; 3854 else if (NewVD->getStorageClass() == SC_Static) 3855 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3856 << SizeRange; 3857 else 3858 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3859 << SizeRange; 3860 return NewVD->setInvalidDecl(); 3861 } 3862 3863 if (FixedTy.isNull()) { 3864 if (NewVD->isFileVarDecl()) 3865 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3866 else 3867 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3868 return NewVD->setInvalidDecl(); 3869 } 3870 3871 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3872 NewVD->setType(FixedTy); 3873 } 3874 3875 if (Previous.empty() && NewVD->isExternC()) { 3876 // Since we did not find anything by this name and we're declaring 3877 // an extern "C" variable, look for a non-visible extern "C" 3878 // declaration with the same name. 3879 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3880 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3881 if (Pos != LocallyScopedExternalDecls.end()) 3882 Previous.addDecl(Pos->second); 3883 } 3884 3885 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3886 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3887 << T; 3888 return NewVD->setInvalidDecl(); 3889 } 3890 3891 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3892 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3893 return NewVD->setInvalidDecl(); 3894 } 3895 3896 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3897 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3898 return NewVD->setInvalidDecl(); 3899 } 3900 3901 // Function pointers and references cannot have qualified function type, only 3902 // function pointer-to-members can do that. 3903 QualType Pointee; 3904 unsigned PtrOrRef = 0; 3905 if (const PointerType *Ptr = T->getAs<PointerType>()) 3906 Pointee = Ptr->getPointeeType(); 3907 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3908 Pointee = Ref->getPointeeType(); 3909 PtrOrRef = 1; 3910 } 3911 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3912 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3913 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3914 << PtrOrRef; 3915 return NewVD->setInvalidDecl(); 3916 } 3917 3918 if (!Previous.empty()) { 3919 Redeclaration = true; 3920 MergeVarDecl(NewVD, Previous); 3921 } 3922} 3923 3924/// \brief Data used with FindOverriddenMethod 3925struct FindOverriddenMethodData { 3926 Sema *S; 3927 CXXMethodDecl *Method; 3928}; 3929 3930/// \brief Member lookup function that determines whether a given C++ 3931/// method overrides a method in a base class, to be used with 3932/// CXXRecordDecl::lookupInBases(). 3933static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3934 CXXBasePath &Path, 3935 void *UserData) { 3936 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3937 3938 FindOverriddenMethodData *Data 3939 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3940 3941 DeclarationName Name = Data->Method->getDeclName(); 3942 3943 // FIXME: Do we care about other names here too? 3944 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3945 // We really want to find the base class destructor here. 3946 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3947 CanQualType CT = Data->S->Context.getCanonicalType(T); 3948 3949 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3950 } 3951 3952 for (Path.Decls = BaseRecord->lookup(Name); 3953 Path.Decls.first != Path.Decls.second; 3954 ++Path.Decls.first) { 3955 NamedDecl *D = *Path.Decls.first; 3956 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3957 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3958 return true; 3959 } 3960 } 3961 3962 return false; 3963} 3964 3965/// AddOverriddenMethods - See if a method overrides any in the base classes, 3966/// and if so, check that it's a valid override and remember it. 3967bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3968 // Look for virtual methods in base classes that this method might override. 3969 CXXBasePaths Paths; 3970 FindOverriddenMethodData Data; 3971 Data.Method = MD; 3972 Data.S = this; 3973 bool AddedAny = false; 3974 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3975 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3976 E = Paths.found_decls_end(); I != E; ++I) { 3977 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3978 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3979 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3980 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 3981 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3982 AddedAny = true; 3983 } 3984 } 3985 } 3986 } 3987 3988 return AddedAny; 3989} 3990 3991static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3992 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3993 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3994 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3995 assert(!Prev.isAmbiguous() && 3996 "Cannot have an ambiguity in previous-declaration lookup"); 3997 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3998 Func != FuncEnd; ++Func) { 3999 if (isa<FunctionDecl>(*Func) && 4000 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 4001 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 4002 } 4003} 4004 4005NamedDecl* 4006Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 4007 QualType R, TypeSourceInfo *TInfo, 4008 LookupResult &Previous, 4009 MultiTemplateParamsArg TemplateParamLists, 4010 bool IsFunctionDefinition, bool &Redeclaration, 4011 SourceLocation DefLoc) { 4012 assert(R.getTypePtr()->isFunctionType()); 4013 4014 // TODO: consider using NameInfo for diagnostic. 4015 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 4016 DeclarationName Name = NameInfo.getName(); 4017 FunctionDecl::StorageClass SC = SC_None; 4018 switch (D.getDeclSpec().getStorageClassSpec()) { 4019 default: assert(0 && "Unknown storage class!"); 4020 case DeclSpec::SCS_auto: 4021 case DeclSpec::SCS_register: 4022 case DeclSpec::SCS_mutable: 4023 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4024 diag::err_typecheck_sclass_func); 4025 D.setInvalidType(); 4026 break; 4027 case DeclSpec::SCS_unspecified: SC = SC_None; break; 4028 case DeclSpec::SCS_extern: SC = SC_Extern; break; 4029 case DeclSpec::SCS_static: { 4030 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 4031 // C99 6.7.1p5: 4032 // The declaration of an identifier for a function that has 4033 // block scope shall have no explicit storage-class specifier 4034 // other than extern 4035 // See also (C++ [dcl.stc]p4). 4036 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4037 diag::err_static_block_func); 4038 SC = SC_None; 4039 } else 4040 SC = SC_Static; 4041 break; 4042 } 4043 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 4044 } 4045 4046 if (D.getDeclSpec().isThreadSpecified()) 4047 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4048 4049 // Do not allow returning a objc interface by-value. 4050 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 4051 Diag(D.getIdentifierLoc(), 4052 diag::err_object_cannot_be_passed_returned_by_value) << 0 4053 << R->getAs<FunctionType>()->getResultType(); 4054 D.setInvalidType(); 4055 } 4056 4057 FunctionDecl *NewFD; 4058 bool isInline = D.getDeclSpec().isInlineSpecified(); 4059 bool isFriend = false; 4060 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 4061 FunctionDecl::StorageClass SCAsWritten 4062 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 4063 FunctionTemplateDecl *FunctionTemplate = 0; 4064 bool isExplicitSpecialization = false; 4065 bool isFunctionTemplateSpecialization = false; 4066 4067 if (!getLangOptions().CPlusPlus) { 4068 assert(!DefLoc.isValid() && "Defaulted functions are a C++ feature"); 4069 4070 // Determine whether the function was written with a 4071 // prototype. This true when: 4072 // - there is a prototype in the declarator, or 4073 // - the type R of the function is some kind of typedef or other reference 4074 // to a type name (which eventually refers to a function type). 4075 bool HasPrototype = 4076 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 4077 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 4078 4079 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4080 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 4081 HasPrototype); 4082 if (D.isInvalidType()) 4083 NewFD->setInvalidDecl(); 4084 4085 // Set the lexical context. 4086 NewFD->setLexicalDeclContext(CurContext); 4087 // Filter out previous declarations that don't match the scope. 4088 FilterLookupForScope(Previous, DC, S, NewFD->hasLinkage(), 4089 /*ExplicitInstantiationOrSpecialization=*/false); 4090 } else { 4091 isFriend = D.getDeclSpec().isFriendSpecified(); 4092 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 4093 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 4094 bool isVirtualOkay = false; 4095 4096 // Check that the return type is not an abstract class type. 4097 // For record types, this is done by the AbstractClassUsageDiagnoser once 4098 // the class has been completely parsed. 4099 if (!DC->isRecord() && 4100 RequireNonAbstractType(D.getIdentifierLoc(), 4101 R->getAs<FunctionType>()->getResultType(), 4102 diag::err_abstract_type_in_decl, 4103 AbstractReturnType)) 4104 D.setInvalidType(); 4105 4106 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 4107 // This is a C++ constructor declaration. 4108 assert(DC->isRecord() && 4109 "Constructors can only be declared in a member context"); 4110 4111 R = CheckConstructorDeclarator(D, R, SC); 4112 4113 // Create the new declaration 4114 CXXConstructorDecl *NewCD = CXXConstructorDecl::Create( 4115 Context, 4116 cast<CXXRecordDecl>(DC), 4117 D.getSourceRange().getBegin(), 4118 NameInfo, R, TInfo, 4119 isExplicit, isInline, 4120 /*isImplicitlyDeclared=*/false); 4121 4122 NewFD = NewCD; 4123 4124 if (DefLoc.isValid()) { 4125 if (NewCD->isDefaultConstructor() || 4126 NewCD->isCopyOrMoveConstructor()) { 4127 NewFD->setDefaulted(); 4128 NewFD->setExplicitlyDefaulted(); 4129 } else { 4130 Diag(DefLoc, diag::err_default_special_members); 4131 } 4132 } 4133 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 4134 // This is a C++ destructor declaration. 4135 if (DC->isRecord()) { 4136 R = CheckDestructorDeclarator(D, R, SC); 4137 4138 NewFD = CXXDestructorDecl::Create(Context, 4139 cast<CXXRecordDecl>(DC), 4140 D.getSourceRange().getBegin(), 4141 NameInfo, R, TInfo, 4142 isInline, 4143 /*isImplicitlyDeclared=*/false); 4144 isVirtualOkay = true; 4145 4146 if (DefLoc.isValid()) { 4147 NewFD->setDefaulted(); 4148 NewFD->setExplicitlyDefaulted(); 4149 } 4150 } else { 4151 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 4152 4153 // Create a FunctionDecl to satisfy the function definition parsing 4154 // code path. 4155 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4156 D.getIdentifierLoc(), Name, R, TInfo, 4157 SC, SCAsWritten, isInline, 4158 /*hasPrototype=*/true); 4159 D.setInvalidType(); 4160 } 4161 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 4162 if (!DC->isRecord()) { 4163 Diag(D.getIdentifierLoc(), 4164 diag::err_conv_function_not_member); 4165 return 0; 4166 } 4167 4168 if (DefLoc.isValid()) 4169 Diag(DefLoc, diag::err_default_special_members); 4170 4171 CheckConversionDeclarator(D, R, SC); 4172 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 4173 D.getSourceRange().getBegin(), 4174 NameInfo, R, TInfo, 4175 isInline, isExplicit, 4176 SourceLocation()); 4177 4178 isVirtualOkay = true; 4179 } else if (DC->isRecord()) { 4180 // If the of the function is the same as the name of the record, then this 4181 // must be an invalid constructor that has a return type. 4182 // (The parser checks for a return type and makes the declarator a 4183 // constructor if it has no return type). 4184 // must have an invalid constructor that has a return type 4185 if (Name.getAsIdentifierInfo() && 4186 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 4187 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 4188 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 4189 << SourceRange(D.getIdentifierLoc()); 4190 return 0; 4191 } 4192 4193 bool isStatic = SC == SC_Static; 4194 4195 // [class.free]p1: 4196 // Any allocation function for a class T is a static member 4197 // (even if not explicitly declared static). 4198 if (Name.getCXXOverloadedOperator() == OO_New || 4199 Name.getCXXOverloadedOperator() == OO_Array_New) 4200 isStatic = true; 4201 4202 // [class.free]p6 Any deallocation function for a class X is a static member 4203 // (even if not explicitly declared static). 4204 if (Name.getCXXOverloadedOperator() == OO_Delete || 4205 Name.getCXXOverloadedOperator() == OO_Array_Delete) 4206 isStatic = true; 4207 4208 // This is a C++ method declaration. 4209 CXXMethodDecl *NewMD = CXXMethodDecl::Create( 4210 Context, cast<CXXRecordDecl>(DC), 4211 D.getSourceRange().getBegin(), 4212 NameInfo, R, TInfo, 4213 isStatic, SCAsWritten, isInline, 4214 SourceLocation()); 4215 NewFD = NewMD; 4216 4217 isVirtualOkay = !isStatic; 4218 4219 if (DefLoc.isValid()) { 4220 if (NewMD->isCopyAssignmentOperator() /* || 4221 NewMD->isMoveAssignmentOperator() */) { 4222 NewFD->setDefaulted(); 4223 NewFD->setExplicitlyDefaulted(); 4224 } else { 4225 Diag(DefLoc, diag::err_default_special_members); 4226 } 4227 } 4228 } else { 4229 if (DefLoc.isValid()) 4230 Diag(DefLoc, diag::err_default_special_members); 4231 4232 // Determine whether the function was written with a 4233 // prototype. This true when: 4234 // - we're in C++ (where every function has a prototype), 4235 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4236 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 4237 true/*HasPrototype*/); 4238 } 4239 4240 if (isFriend && !isInline && IsFunctionDefinition) { 4241 // C++ [class.friend]p5 4242 // A function can be defined in a friend declaration of a 4243 // class . . . . Such a function is implicitly inline. 4244 NewFD->setImplicitlyInline(); 4245 } 4246 4247 SetNestedNameSpecifier(NewFD, D); 4248 isExplicitSpecialization = false; 4249 isFunctionTemplateSpecialization = false; 4250 if (D.isInvalidType()) 4251 NewFD->setInvalidDecl(); 4252 4253 // Set the lexical context. If the declarator has a C++ 4254 // scope specifier, or is the object of a friend declaration, the 4255 // lexical context will be different from the semantic context. 4256 NewFD->setLexicalDeclContext(CurContext); 4257 4258 // Match up the template parameter lists with the scope specifier, then 4259 // determine whether we have a template or a template specialization. 4260 bool Invalid = false; 4261 if (TemplateParameterList *TemplateParams 4262 = MatchTemplateParametersToScopeSpecifier( 4263 D.getDeclSpec().getSourceRange().getBegin(), 4264 D.getCXXScopeSpec(), 4265 TemplateParamLists.get(), 4266 TemplateParamLists.size(), 4267 isFriend, 4268 isExplicitSpecialization, 4269 Invalid)) { 4270 if (TemplateParams->size() > 0) { 4271 // This is a function template 4272 4273 // Check that we can declare a template here. 4274 if (CheckTemplateDeclScope(S, TemplateParams)) 4275 return 0; 4276 4277 // A destructor cannot be a template. 4278 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 4279 Diag(NewFD->getLocation(), diag::err_destructor_template); 4280 return 0; 4281 } 4282 4283 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 4284 NewFD->getLocation(), 4285 Name, TemplateParams, 4286 NewFD); 4287 FunctionTemplate->setLexicalDeclContext(CurContext); 4288 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 4289 4290 // For source fidelity, store the other template param lists. 4291 if (TemplateParamLists.size() > 1) { 4292 NewFD->setTemplateParameterListsInfo(Context, 4293 TemplateParamLists.size() - 1, 4294 TemplateParamLists.release()); 4295 } 4296 } else { 4297 // This is a function template specialization. 4298 isFunctionTemplateSpecialization = true; 4299 // For source fidelity, store all the template param lists. 4300 NewFD->setTemplateParameterListsInfo(Context, 4301 TemplateParamLists.size(), 4302 TemplateParamLists.release()); 4303 4304 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 4305 if (isFriend) { 4306 // We want to remove the "template<>", found here. 4307 SourceRange RemoveRange = TemplateParams->getSourceRange(); 4308 4309 // If we remove the template<> and the name is not a 4310 // template-id, we're actually silently creating a problem: 4311 // the friend declaration will refer to an untemplated decl, 4312 // and clearly the user wants a template specialization. So 4313 // we need to insert '<>' after the name. 4314 SourceLocation InsertLoc; 4315 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 4316 InsertLoc = D.getName().getSourceRange().getEnd(); 4317 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 4318 } 4319 4320 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 4321 << Name << RemoveRange 4322 << FixItHint::CreateRemoval(RemoveRange) 4323 << FixItHint::CreateInsertion(InsertLoc, "<>"); 4324 } 4325 } 4326 } 4327 else { 4328 // All template param lists were matched against the scope specifier: 4329 // this is NOT (an explicit specialization of) a template. 4330 if (TemplateParamLists.size() > 0) 4331 // For source fidelity, store all the template param lists. 4332 NewFD->setTemplateParameterListsInfo(Context, 4333 TemplateParamLists.size(), 4334 TemplateParamLists.release()); 4335 } 4336 4337 if (Invalid) { 4338 NewFD->setInvalidDecl(); 4339 if (FunctionTemplate) 4340 FunctionTemplate->setInvalidDecl(); 4341 } 4342 4343 // C++ [dcl.fct.spec]p5: 4344 // The virtual specifier shall only be used in declarations of 4345 // nonstatic class member functions that appear within a 4346 // member-specification of a class declaration; see 10.3. 4347 // 4348 if (isVirtual && !NewFD->isInvalidDecl()) { 4349 if (!isVirtualOkay) { 4350 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4351 diag::err_virtual_non_function); 4352 } else if (!CurContext->isRecord()) { 4353 // 'virtual' was specified outside of the class. 4354 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4355 diag::err_virtual_out_of_class) 4356 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 4357 } else if (NewFD->getDescribedFunctionTemplate()) { 4358 // C++ [temp.mem]p3: 4359 // A member function template shall not be virtual. 4360 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4361 diag::err_virtual_member_function_template) 4362 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 4363 } else { 4364 // Okay: Add virtual to the method. 4365 NewFD->setVirtualAsWritten(true); 4366 } 4367 } 4368 4369 // C++ [dcl.fct.spec]p3: 4370 // The inline specifier shall not appear on a block scope function declaration. 4371 if (isInline && !NewFD->isInvalidDecl()) { 4372 if (CurContext->isFunctionOrMethod()) { 4373 // 'inline' is not allowed on block scope function declaration. 4374 Diag(D.getDeclSpec().getInlineSpecLoc(), 4375 diag::err_inline_declaration_block_scope) << Name 4376 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 4377 } 4378 } 4379 4380 // C++ [dcl.fct.spec]p6: 4381 // The explicit specifier shall be used only in the declaration of a 4382 // constructor or conversion function within its class definition; see 12.3.1 4383 // and 12.3.2. 4384 if (isExplicit && !NewFD->isInvalidDecl()) { 4385 if (!CurContext->isRecord()) { 4386 // 'explicit' was specified outside of the class. 4387 Diag(D.getDeclSpec().getExplicitSpecLoc(), 4388 diag::err_explicit_out_of_class) 4389 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 4390 } else if (!isa<CXXConstructorDecl>(NewFD) && 4391 !isa<CXXConversionDecl>(NewFD)) { 4392 // 'explicit' was specified on a function that wasn't a constructor 4393 // or conversion function. 4394 Diag(D.getDeclSpec().getExplicitSpecLoc(), 4395 diag::err_explicit_non_ctor_or_conv_function) 4396 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 4397 } 4398 } 4399 4400 // Filter out previous declarations that don't match the scope. 4401 FilterLookupForScope(Previous, DC, S, NewFD->hasLinkage(), 4402 isExplicitSpecialization || 4403 isFunctionTemplateSpecialization); 4404 4405 if (isFriend) { 4406 // For now, claim that the objects have no previous declaration. 4407 if (FunctionTemplate) { 4408 FunctionTemplate->setObjectOfFriendDecl(false); 4409 FunctionTemplate->setAccess(AS_public); 4410 } 4411 NewFD->setObjectOfFriendDecl(false); 4412 NewFD->setAccess(AS_public); 4413 } 4414 4415 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && IsFunctionDefinition) { 4416 // A method is implicitly inline if it's defined in its class 4417 // definition. 4418 NewFD->setImplicitlyInline(); 4419 } 4420 4421 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 4422 !CurContext->isRecord()) { 4423 // C++ [class.static]p1: 4424 // A data or function member of a class may be declared static 4425 // in a class definition, in which case it is a static member of 4426 // the class. 4427 4428 // Complain about the 'static' specifier if it's on an out-of-line 4429 // member function definition. 4430 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4431 diag::err_static_out_of_line) 4432 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4433 } 4434 } 4435 4436 // Handle GNU asm-label extension (encoded as an attribute). 4437 if (Expr *E = (Expr*) D.getAsmLabel()) { 4438 // The parser guarantees this is a string. 4439 StringLiteral *SE = cast<StringLiteral>(E); 4440 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 4441 SE->getString())); 4442 } 4443 4444 // Copy the parameter declarations from the declarator D to the function 4445 // declaration NewFD, if they are available. First scavenge them into Params. 4446 llvm::SmallVector<ParmVarDecl*, 16> Params; 4447 if (D.isFunctionDeclarator()) { 4448 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 4449 4450 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 4451 // function that takes no arguments, not a function that takes a 4452 // single void argument. 4453 // We let through "const void" here because Sema::GetTypeForDeclarator 4454 // already checks for that case. 4455 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 4456 FTI.ArgInfo[0].Param && 4457 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 4458 // Empty arg list, don't push any params. 4459 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 4460 4461 // In C++, the empty parameter-type-list must be spelled "void"; a 4462 // typedef of void is not permitted. 4463 if (getLangOptions().CPlusPlus && 4464 Param->getType().getUnqualifiedType() != Context.VoidTy) { 4465 bool IsTypeAlias = false; 4466 if (const TypedefType *TT = Param->getType()->getAs<TypedefType>()) 4467 IsTypeAlias = isa<TypeAliasDecl>(TT->getDecl()); 4468 else if (const TemplateSpecializationType *TST = 4469 Param->getType()->getAs<TemplateSpecializationType>()) 4470 IsTypeAlias = TST->isTypeAlias(); 4471 Diag(Param->getLocation(), diag::err_param_typedef_of_void) 4472 << IsTypeAlias; 4473 } 4474 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 4475 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 4476 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 4477 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 4478 Param->setDeclContext(NewFD); 4479 Params.push_back(Param); 4480 4481 if (Param->isInvalidDecl()) 4482 NewFD->setInvalidDecl(); 4483 } 4484 } 4485 4486 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 4487 // When we're declaring a function with a typedef, typeof, etc as in the 4488 // following example, we'll need to synthesize (unnamed) 4489 // parameters for use in the declaration. 4490 // 4491 // @code 4492 // typedef void fn(int); 4493 // fn f; 4494 // @endcode 4495 4496 // Synthesize a parameter for each argument type. 4497 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 4498 AE = FT->arg_type_end(); AI != AE; ++AI) { 4499 ParmVarDecl *Param = 4500 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 4501 Param->setScopeInfo(0, Params.size()); 4502 Params.push_back(Param); 4503 } 4504 } else { 4505 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 4506 "Should not need args for typedef of non-prototype fn"); 4507 } 4508 // Finally, we know we have the right number of parameters, install them. 4509 NewFD->setParams(Params.data(), Params.size()); 4510 4511 // Process the non-inheritable attributes on this declaration. 4512 ProcessDeclAttributes(S, NewFD, D, 4513 /*NonInheritable=*/true, /*Inheritable=*/false); 4514 4515 if (!getLangOptions().CPlusPlus) { 4516 // Perform semantic checking on the function declaration. 4517 bool isExplctSpecialization=false; 4518 CheckFunctionDeclaration(S, NewFD, Previous, isExplctSpecialization, 4519 Redeclaration); 4520 assert((NewFD->isInvalidDecl() || !Redeclaration || 4521 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4522 "previous declaration set still overloaded"); 4523 } else { 4524 // If the declarator is a template-id, translate the parser's template 4525 // argument list into our AST format. 4526 bool HasExplicitTemplateArgs = false; 4527 TemplateArgumentListInfo TemplateArgs; 4528 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4529 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4530 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4531 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4532 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4533 TemplateId->getTemplateArgs(), 4534 TemplateId->NumArgs); 4535 translateTemplateArguments(TemplateArgsPtr, 4536 TemplateArgs); 4537 TemplateArgsPtr.release(); 4538 4539 HasExplicitTemplateArgs = true; 4540 4541 if (FunctionTemplate) { 4542 // Function template with explicit template arguments. 4543 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 4544 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 4545 4546 HasExplicitTemplateArgs = false; 4547 } else if (!isFunctionTemplateSpecialization && 4548 !D.getDeclSpec().isFriendSpecified()) { 4549 // We have encountered something that the user meant to be a 4550 // specialization (because it has explicitly-specified template 4551 // arguments) but that was not introduced with a "template<>" (or had 4552 // too few of them). 4553 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 4554 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 4555 << FixItHint::CreateInsertion( 4556 D.getDeclSpec().getSourceRange().getBegin(), 4557 "template<> "); 4558 isFunctionTemplateSpecialization = true; 4559 } else { 4560 // "friend void foo<>(int);" is an implicit specialization decl. 4561 isFunctionTemplateSpecialization = true; 4562 } 4563 } else if (isFriend && isFunctionTemplateSpecialization) { 4564 // This combination is only possible in a recovery case; the user 4565 // wrote something like: 4566 // template <> friend void foo(int); 4567 // which we're recovering from as if the user had written: 4568 // friend void foo<>(int); 4569 // Go ahead and fake up a template id. 4570 HasExplicitTemplateArgs = true; 4571 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 4572 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 4573 } 4574 4575 // If it's a friend (and only if it's a friend), it's possible 4576 // that either the specialized function type or the specialized 4577 // template is dependent, and therefore matching will fail. In 4578 // this case, don't check the specialization yet. 4579 if (isFunctionTemplateSpecialization && isFriend && 4580 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 4581 assert(HasExplicitTemplateArgs && 4582 "friend function specialization without template args"); 4583 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 4584 Previous)) 4585 NewFD->setInvalidDecl(); 4586 } else if (isFunctionTemplateSpecialization) { 4587 if (CurContext->isDependentContext() && CurContext->isRecord() 4588 && !isFriend) { 4589 Diag(NewFD->getLocation(), diag::err_function_specialization_in_class) 4590 << NewFD->getDeclName(); 4591 NewFD->setInvalidDecl(); 4592 return 0; 4593 } else if (CheckFunctionTemplateSpecialization(NewFD, 4594 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4595 Previous)) 4596 NewFD->setInvalidDecl(); 4597 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 4598 if (CheckMemberSpecialization(NewFD, Previous)) 4599 NewFD->setInvalidDecl(); 4600 } 4601 4602 // Perform semantic checking on the function declaration. 4603 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4604 Redeclaration); 4605 4606 assert((NewFD->isInvalidDecl() || !Redeclaration || 4607 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4608 "previous declaration set still overloaded"); 4609 4610 NamedDecl *PrincipalDecl = (FunctionTemplate 4611 ? cast<NamedDecl>(FunctionTemplate) 4612 : NewFD); 4613 4614 if (isFriend && Redeclaration) { 4615 AccessSpecifier Access = AS_public; 4616 if (!NewFD->isInvalidDecl()) 4617 Access = NewFD->getPreviousDeclaration()->getAccess(); 4618 4619 NewFD->setAccess(Access); 4620 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 4621 4622 PrincipalDecl->setObjectOfFriendDecl(true); 4623 } 4624 4625 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 4626 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 4627 PrincipalDecl->setNonMemberOperator(); 4628 4629 // If we have a function template, check the template parameter 4630 // list. This will check and merge default template arguments. 4631 if (FunctionTemplate) { 4632 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 4633 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 4634 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 4635 D.getDeclSpec().isFriendSpecified() 4636 ? (IsFunctionDefinition 4637 ? TPC_FriendFunctionTemplateDefinition 4638 : TPC_FriendFunctionTemplate) 4639 : (D.getCXXScopeSpec().isSet() && 4640 DC && DC->isRecord() && 4641 DC->isDependentContext()) 4642 ? TPC_ClassTemplateMember 4643 : TPC_FunctionTemplate); 4644 } 4645 4646 if (NewFD->isInvalidDecl()) { 4647 // Ignore all the rest of this. 4648 } else if (!Redeclaration) { 4649 // Fake up an access specifier if it's supposed to be a class member. 4650 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 4651 NewFD->setAccess(AS_public); 4652 4653 // Qualified decls generally require a previous declaration. 4654 if (D.getCXXScopeSpec().isSet()) { 4655 // ...with the major exception of templated-scope or 4656 // dependent-scope friend declarations. 4657 4658 // TODO: we currently also suppress this check in dependent 4659 // contexts because (1) the parameter depth will be off when 4660 // matching friend templates and (2) we might actually be 4661 // selecting a friend based on a dependent factor. But there 4662 // are situations where these conditions don't apply and we 4663 // can actually do this check immediately. 4664 if (isFriend && 4665 (TemplateParamLists.size() || 4666 D.getCXXScopeSpec().getScopeRep()->isDependent() || 4667 CurContext->isDependentContext())) { 4668 // ignore these 4669 } else { 4670 // The user tried to provide an out-of-line definition for a 4671 // function that is a member of a class or namespace, but there 4672 // was no such member function declared (C++ [class.mfct]p2, 4673 // C++ [namespace.memdef]p2). For example: 4674 // 4675 // class X { 4676 // void f() const; 4677 // }; 4678 // 4679 // void X::f() { } // ill-formed 4680 // 4681 // Complain about this problem, and attempt to suggest close 4682 // matches (e.g., those that differ only in cv-qualifiers and 4683 // whether the parameter types are references). 4684 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 4685 << Name << DC << D.getCXXScopeSpec().getRange(); 4686 NewFD->setInvalidDecl(); 4687 4688 DiagnoseInvalidRedeclaration(*this, NewFD); 4689 } 4690 4691 // Unqualified local friend declarations are required to resolve 4692 // to something. 4693 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 4694 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 4695 NewFD->setInvalidDecl(); 4696 DiagnoseInvalidRedeclaration(*this, NewFD); 4697 } 4698 4699 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 4700 !isFriend && !isFunctionTemplateSpecialization && 4701 !isExplicitSpecialization) { 4702 // An out-of-line member function declaration must also be a 4703 // definition (C++ [dcl.meaning]p1). 4704 // Note that this is not the case for explicit specializations of 4705 // function templates or member functions of class templates, per 4706 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 4707 // for compatibility with old SWIG code which likes to generate them. 4708 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 4709 << D.getCXXScopeSpec().getRange(); 4710 } 4711 } 4712 4713 4714 // Handle attributes. We need to have merged decls when handling attributes 4715 // (for example to check for conflicts, etc). 4716 // FIXME: This needs to happen before we merge declarations. Then, 4717 // let attribute merging cope with attribute conflicts. 4718 ProcessDeclAttributes(S, NewFD, D, 4719 /*NonInheritable=*/false, /*Inheritable=*/true); 4720 4721 // attributes declared post-definition are currently ignored 4722 // FIXME: This should happen during attribute merging 4723 if (Redeclaration && Previous.isSingleResult()) { 4724 const FunctionDecl *Def; 4725 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 4726 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 4727 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 4728 Diag(Def->getLocation(), diag::note_previous_definition); 4729 } 4730 } 4731 4732 AddKnownFunctionAttributes(NewFD); 4733 4734 if (NewFD->hasAttr<OverloadableAttr>() && 4735 !NewFD->getType()->getAs<FunctionProtoType>()) { 4736 Diag(NewFD->getLocation(), 4737 diag::err_attribute_overloadable_no_prototype) 4738 << NewFD; 4739 4740 // Turn this into a variadic function with no parameters. 4741 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 4742 FunctionProtoType::ExtProtoInfo EPI; 4743 EPI.Variadic = true; 4744 EPI.ExtInfo = FT->getExtInfo(); 4745 4746 QualType R = Context.getFunctionType(FT->getResultType(), 0, 0, EPI); 4747 NewFD->setType(R); 4748 } 4749 4750 // If there's a #pragma GCC visibility in scope, and this isn't a class 4751 // member, set the visibility of this function. 4752 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 4753 AddPushedVisibilityAttribute(NewFD); 4754 4755 // If this is a locally-scoped extern C function, update the 4756 // map of such names. 4757 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 4758 && !NewFD->isInvalidDecl()) 4759 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 4760 4761 // Set this FunctionDecl's range up to the right paren. 4762 NewFD->setRangeEnd(D.getSourceRange().getEnd()); 4763 4764 if (getLangOptions().CPlusPlus) { 4765 if (FunctionTemplate) { 4766 if (NewFD->isInvalidDecl()) 4767 FunctionTemplate->setInvalidDecl(); 4768 return FunctionTemplate; 4769 } 4770 } 4771 4772 MarkUnusedFileScopedDecl(NewFD); 4773 4774 if (getLangOptions().CUDA) 4775 if (IdentifierInfo *II = NewFD->getIdentifier()) 4776 if (!NewFD->isInvalidDecl() && 4777 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4778 if (II->isStr("cudaConfigureCall")) { 4779 if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) 4780 Diag(NewFD->getLocation(), diag::err_config_scalar_return); 4781 4782 Context.setcudaConfigureCallDecl(NewFD); 4783 } 4784 } 4785 4786 return NewFD; 4787} 4788 4789/// \brief Perform semantic checking of a new function declaration. 4790/// 4791/// Performs semantic analysis of the new function declaration 4792/// NewFD. This routine performs all semantic checking that does not 4793/// require the actual declarator involved in the declaration, and is 4794/// used both for the declaration of functions as they are parsed 4795/// (called via ActOnDeclarator) and for the declaration of functions 4796/// that have been instantiated via C++ template instantiation (called 4797/// via InstantiateDecl). 4798/// 4799/// \param IsExplicitSpecialiation whether this new function declaration is 4800/// an explicit specialization of the previous declaration. 4801/// 4802/// This sets NewFD->isInvalidDecl() to true if there was an error. 4803void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 4804 LookupResult &Previous, 4805 bool IsExplicitSpecialization, 4806 bool &Redeclaration) { 4807 // If NewFD is already known erroneous, don't do any of this checking. 4808 if (NewFD->isInvalidDecl()) { 4809 // If this is a class member, mark the class invalid immediately. 4810 // This avoids some consistency errors later. 4811 if (isa<CXXMethodDecl>(NewFD)) 4812 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 4813 4814 return; 4815 } 4816 4817 if (NewFD->getResultType()->isVariablyModifiedType()) { 4818 // Functions returning a variably modified type violate C99 6.7.5.2p2 4819 // because all functions have linkage. 4820 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 4821 return NewFD->setInvalidDecl(); 4822 } 4823 4824 if (NewFD->isMain()) 4825 CheckMain(NewFD); 4826 4827 // Check for a previous declaration of this name. 4828 if (Previous.empty() && NewFD->isExternC()) { 4829 // Since we did not find anything by this name and we're declaring 4830 // an extern "C" function, look for a non-visible extern "C" 4831 // declaration with the same name. 4832 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4833 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 4834 if (Pos != LocallyScopedExternalDecls.end()) 4835 Previous.addDecl(Pos->second); 4836 } 4837 4838 // Merge or overload the declaration with an existing declaration of 4839 // the same name, if appropriate. 4840 if (!Previous.empty()) { 4841 // Determine whether NewFD is an overload of PrevDecl or 4842 // a declaration that requires merging. If it's an overload, 4843 // there's no more work to do here; we'll just add the new 4844 // function to the scope. 4845 4846 NamedDecl *OldDecl = 0; 4847 if (!AllowOverloadingOfFunction(Previous, Context)) { 4848 Redeclaration = true; 4849 OldDecl = Previous.getFoundDecl(); 4850 } else { 4851 switch (CheckOverload(S, NewFD, Previous, OldDecl, 4852 /*NewIsUsingDecl*/ false)) { 4853 case Ovl_Match: 4854 Redeclaration = true; 4855 break; 4856 4857 case Ovl_NonFunction: 4858 Redeclaration = true; 4859 break; 4860 4861 case Ovl_Overload: 4862 Redeclaration = false; 4863 break; 4864 } 4865 4866 if (!getLangOptions().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { 4867 // If a function name is overloadable in C, then every function 4868 // with that name must be marked "overloadable". 4869 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 4870 << Redeclaration << NewFD; 4871 NamedDecl *OverloadedDecl = 0; 4872 if (Redeclaration) 4873 OverloadedDecl = OldDecl; 4874 else if (!Previous.empty()) 4875 OverloadedDecl = Previous.getRepresentativeDecl(); 4876 if (OverloadedDecl) 4877 Diag(OverloadedDecl->getLocation(), 4878 diag::note_attribute_overloadable_prev_overload); 4879 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), 4880 Context)); 4881 } 4882 } 4883 4884 if (Redeclaration) { 4885 // NewFD and OldDecl represent declarations that need to be 4886 // merged. 4887 if (MergeFunctionDecl(NewFD, OldDecl)) 4888 return NewFD->setInvalidDecl(); 4889 4890 Previous.clear(); 4891 Previous.addDecl(OldDecl); 4892 4893 if (FunctionTemplateDecl *OldTemplateDecl 4894 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4895 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4896 FunctionTemplateDecl *NewTemplateDecl 4897 = NewFD->getDescribedFunctionTemplate(); 4898 assert(NewTemplateDecl && "Template/non-template mismatch"); 4899 if (CXXMethodDecl *Method 4900 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4901 Method->setAccess(OldTemplateDecl->getAccess()); 4902 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4903 } 4904 4905 // If this is an explicit specialization of a member that is a function 4906 // template, mark it as a member specialization. 4907 if (IsExplicitSpecialization && 4908 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 4909 NewTemplateDecl->setMemberSpecialization(); 4910 assert(OldTemplateDecl->isMemberSpecialization()); 4911 } 4912 } else { 4913 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 4914 NewFD->setAccess(OldDecl->getAccess()); 4915 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 4916 } 4917 } 4918 } 4919 4920 // Semantic checking for this function declaration (in isolation). 4921 if (getLangOptions().CPlusPlus) { 4922 // C++-specific checks. 4923 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 4924 CheckConstructor(Constructor); 4925 } else if (CXXDestructorDecl *Destructor = 4926 dyn_cast<CXXDestructorDecl>(NewFD)) { 4927 CXXRecordDecl *Record = Destructor->getParent(); 4928 QualType ClassType = Context.getTypeDeclType(Record); 4929 4930 // FIXME: Shouldn't we be able to perform this check even when the class 4931 // type is dependent? Both gcc and edg can handle that. 4932 if (!ClassType->isDependentType()) { 4933 DeclarationName Name 4934 = Context.DeclarationNames.getCXXDestructorName( 4935 Context.getCanonicalType(ClassType)); 4936 if (NewFD->getDeclName() != Name) { 4937 Diag(NewFD->getLocation(), diag::err_destructor_name); 4938 return NewFD->setInvalidDecl(); 4939 } 4940 } 4941 } else if (CXXConversionDecl *Conversion 4942 = dyn_cast<CXXConversionDecl>(NewFD)) { 4943 ActOnConversionDeclarator(Conversion); 4944 } 4945 4946 // Find any virtual functions that this function overrides. 4947 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4948 if (!Method->isFunctionTemplateSpecialization() && 4949 !Method->getDescribedFunctionTemplate()) { 4950 if (AddOverriddenMethods(Method->getParent(), Method)) { 4951 // If the function was marked as "static", we have a problem. 4952 if (NewFD->getStorageClass() == SC_Static) { 4953 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4954 << NewFD->getDeclName(); 4955 for (CXXMethodDecl::method_iterator 4956 Overridden = Method->begin_overridden_methods(), 4957 OverriddenEnd = Method->end_overridden_methods(); 4958 Overridden != OverriddenEnd; 4959 ++Overridden) { 4960 Diag((*Overridden)->getLocation(), 4961 diag::note_overridden_virtual_function); 4962 } 4963 } 4964 } 4965 } 4966 } 4967 4968 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4969 if (NewFD->isOverloadedOperator() && 4970 CheckOverloadedOperatorDeclaration(NewFD)) 4971 return NewFD->setInvalidDecl(); 4972 4973 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4974 if (NewFD->getLiteralIdentifier() && 4975 CheckLiteralOperatorDeclaration(NewFD)) 4976 return NewFD->setInvalidDecl(); 4977 4978 // In C++, check default arguments now that we have merged decls. Unless 4979 // the lexical context is the class, because in this case this is done 4980 // during delayed parsing anyway. 4981 if (!CurContext->isRecord()) 4982 CheckCXXDefaultArguments(NewFD); 4983 4984 // If this function declares a builtin function, check the type of this 4985 // declaration against the expected type for the builtin. 4986 if (unsigned BuiltinID = NewFD->getBuiltinID()) { 4987 ASTContext::GetBuiltinTypeError Error; 4988 QualType T = Context.GetBuiltinType(BuiltinID, Error); 4989 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { 4990 // The type of this function differs from the type of the builtin, 4991 // so forget about the builtin entirely. 4992 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); 4993 } 4994 } 4995 } 4996} 4997 4998void Sema::CheckMain(FunctionDecl* FD) { 4999 // C++ [basic.start.main]p3: A program that declares main to be inline 5000 // or static is ill-formed. 5001 // C99 6.7.4p4: In a hosted environment, the inline function specifier 5002 // shall not appear in a declaration of main. 5003 // static main is not an error under C99, but we should warn about it. 5004 bool isInline = FD->isInlineSpecified(); 5005 bool isStatic = FD->getStorageClass() == SC_Static; 5006 if (isInline || isStatic) { 5007 unsigned diagID = diag::warn_unusual_main_decl; 5008 if (isInline || getLangOptions().CPlusPlus) 5009 diagID = diag::err_unusual_main_decl; 5010 5011 int which = isStatic + (isInline << 1) - 1; 5012 Diag(FD->getLocation(), diagID) << which; 5013 } 5014 5015 QualType T = FD->getType(); 5016 assert(T->isFunctionType() && "function decl is not of function type"); 5017 const FunctionType* FT = T->getAs<FunctionType>(); 5018 5019 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 5020 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 5021 FD->setInvalidDecl(true); 5022 } 5023 5024 // Treat protoless main() as nullary. 5025 if (isa<FunctionNoProtoType>(FT)) return; 5026 5027 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 5028 unsigned nparams = FTP->getNumArgs(); 5029 assert(FD->getNumParams() == nparams); 5030 5031 bool HasExtraParameters = (nparams > 3); 5032 5033 // Darwin passes an undocumented fourth argument of type char**. If 5034 // other platforms start sprouting these, the logic below will start 5035 // getting shifty. 5036 if (nparams == 4 && Context.Target.getTriple().isOSDarwin()) 5037 HasExtraParameters = false; 5038 5039 if (HasExtraParameters) { 5040 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 5041 FD->setInvalidDecl(true); 5042 nparams = 3; 5043 } 5044 5045 // FIXME: a lot of the following diagnostics would be improved 5046 // if we had some location information about types. 5047 5048 QualType CharPP = 5049 Context.getPointerType(Context.getPointerType(Context.CharTy)); 5050 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 5051 5052 for (unsigned i = 0; i < nparams; ++i) { 5053 QualType AT = FTP->getArgType(i); 5054 5055 bool mismatch = true; 5056 5057 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 5058 mismatch = false; 5059 else if (Expected[i] == CharPP) { 5060 // As an extension, the following forms are okay: 5061 // char const ** 5062 // char const * const * 5063 // char * const * 5064 5065 QualifierCollector qs; 5066 const PointerType* PT; 5067 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 5068 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 5069 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 5070 qs.removeConst(); 5071 mismatch = !qs.empty(); 5072 } 5073 } 5074 5075 if (mismatch) { 5076 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 5077 // TODO: suggest replacing given type with expected type 5078 FD->setInvalidDecl(true); 5079 } 5080 } 5081 5082 if (nparams == 1 && !FD->isInvalidDecl()) { 5083 Diag(FD->getLocation(), diag::warn_main_one_arg); 5084 } 5085 5086 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 5087 Diag(FD->getLocation(), diag::err_main_template_decl); 5088 FD->setInvalidDecl(); 5089 } 5090} 5091 5092bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 5093 // FIXME: Need strict checking. In C89, we need to check for 5094 // any assignment, increment, decrement, function-calls, or 5095 // commas outside of a sizeof. In C99, it's the same list, 5096 // except that the aforementioned are allowed in unevaluated 5097 // expressions. Everything else falls under the 5098 // "may accept other forms of constant expressions" exception. 5099 // (We never end up here for C++, so the constant expression 5100 // rules there don't matter.) 5101 if (Init->isConstantInitializer(Context, false)) 5102 return false; 5103 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 5104 << Init->getSourceRange(); 5105 return true; 5106} 5107 5108namespace { 5109 // Visits an initialization expression to see if OrigDecl is evaluated in 5110 // its own initialization and throws a warning if it does. 5111 class SelfReferenceChecker 5112 : public EvaluatedExprVisitor<SelfReferenceChecker> { 5113 Sema &S; 5114 Decl *OrigDecl; 5115 5116 public: 5117 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited; 5118 5119 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context), 5120 S(S), OrigDecl(OrigDecl) { } 5121 5122 void VisitExpr(Expr *E) { 5123 if (isa<ObjCMessageExpr>(*E)) return; 5124 Inherited::VisitExpr(E); 5125 } 5126 5127 void VisitImplicitCastExpr(ImplicitCastExpr *E) { 5128 CheckForSelfReference(E); 5129 Inherited::VisitImplicitCastExpr(E); 5130 } 5131 5132 void CheckForSelfReference(ImplicitCastExpr *E) { 5133 if (E->getCastKind() != CK_LValueToRValue) return; 5134 Expr* SubExpr = E->getSubExpr()->IgnoreParenImpCasts(); 5135 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SubExpr); 5136 if (!DRE) return; 5137 Decl* ReferenceDecl = DRE->getDecl(); 5138 if (OrigDecl != ReferenceDecl) return; 5139 LookupResult Result(S, DRE->getNameInfo(), Sema::LookupOrdinaryName, 5140 Sema::NotForRedeclaration); 5141 S.Diag(SubExpr->getLocStart(), diag::warn_uninit_self_reference_in_init) 5142 << Result.getLookupName() << OrigDecl->getLocation() 5143 << SubExpr->getSourceRange(); 5144 } 5145 }; 5146} 5147 5148/// AddInitializerToDecl - Adds the initializer Init to the 5149/// declaration dcl. If DirectInit is true, this is C++ direct 5150/// initialization rather than copy initialization. 5151void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 5152 bool DirectInit, bool TypeMayContainAuto) { 5153 // If there is no declaration, there was an error parsing it. Just ignore 5154 // the initializer. 5155 if (RealDecl == 0 || RealDecl->isInvalidDecl()) 5156 return; 5157 5158 // Check for self-references within variable initializers. 5159 if (VarDecl *vd = dyn_cast<VarDecl>(RealDecl)) { 5160 // Variables declared within a function/method body are handled 5161 // by a dataflow analysis. 5162 if (!vd->hasLocalStorage() && !vd->isStaticLocal()) 5163 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 5164 } 5165 else { 5166 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 5167 } 5168 5169 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 5170 // With declarators parsed the way they are, the parser cannot 5171 // distinguish between a normal initializer and a pure-specifier. 5172 // Thus this grotesque test. 5173 IntegerLiteral *IL; 5174 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 5175 Context.getCanonicalType(IL->getType()) == Context.IntTy) 5176 CheckPureMethod(Method, Init->getSourceRange()); 5177 else { 5178 Diag(Method->getLocation(), diag::err_member_function_initialization) 5179 << Method->getDeclName() << Init->getSourceRange(); 5180 Method->setInvalidDecl(); 5181 } 5182 return; 5183 } 5184 5185 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 5186 if (!VDecl) { 5187 if (getLangOptions().CPlusPlus && 5188 RealDecl->getLexicalDeclContext()->isRecord() && 5189 isa<NamedDecl>(RealDecl)) 5190 Diag(RealDecl->getLocation(), diag::err_member_initialization); 5191 else 5192 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 5193 RealDecl->setInvalidDecl(); 5194 return; 5195 } 5196 5197 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 5198 if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) { 5199 TypeSourceInfo *DeducedType = 0; 5200 if (!DeduceAutoType(VDecl->getTypeSourceInfo(), Init, DeducedType)) 5201 Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure) 5202 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 5203 << Init->getSourceRange(); 5204 if (!DeducedType) { 5205 RealDecl->setInvalidDecl(); 5206 return; 5207 } 5208 VDecl->setTypeSourceInfo(DeducedType); 5209 VDecl->setType(DeducedType->getType()); 5210 5211 // If this is a redeclaration, check that the type we just deduced matches 5212 // the previously declared type. 5213 if (VarDecl *Old = VDecl->getPreviousDeclaration()) 5214 MergeVarDeclTypes(VDecl, Old); 5215 } 5216 5217 5218 // A definition must end up with a complete type, which means it must be 5219 // complete with the restriction that an array type might be completed by the 5220 // initializer; note that later code assumes this restriction. 5221 QualType BaseDeclType = VDecl->getType(); 5222 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 5223 BaseDeclType = Array->getElementType(); 5224 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 5225 diag::err_typecheck_decl_incomplete_type)) { 5226 RealDecl->setInvalidDecl(); 5227 return; 5228 } 5229 5230 // The variable can not have an abstract class type. 5231 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 5232 diag::err_abstract_type_in_decl, 5233 AbstractVariableType)) 5234 VDecl->setInvalidDecl(); 5235 5236 const VarDecl *Def; 5237 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 5238 Diag(VDecl->getLocation(), diag::err_redefinition) 5239 << VDecl->getDeclName(); 5240 Diag(Def->getLocation(), diag::note_previous_definition); 5241 VDecl->setInvalidDecl(); 5242 return; 5243 } 5244 5245 const VarDecl* PrevInit = 0; 5246 if (getLangOptions().CPlusPlus) { 5247 // C++ [class.static.data]p4 5248 // If a static data member is of const integral or const 5249 // enumeration type, its declaration in the class definition can 5250 // specify a constant-initializer which shall be an integral 5251 // constant expression (5.19). In that case, the member can appear 5252 // in integral constant expressions. The member shall still be 5253 // defined in a namespace scope if it is used in the program and the 5254 // namespace scope definition shall not contain an initializer. 5255 // 5256 // We already performed a redefinition check above, but for static 5257 // data members we also need to check whether there was an in-class 5258 // declaration with an initializer. 5259 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 5260 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 5261 Diag(PrevInit->getLocation(), diag::note_previous_definition); 5262 return; 5263 } 5264 5265 if (VDecl->hasLocalStorage()) 5266 getCurFunction()->setHasBranchProtectedScope(); 5267 5268 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { 5269 VDecl->setInvalidDecl(); 5270 return; 5271 } 5272 } 5273 5274 // Capture the variable that is being initialized and the style of 5275 // initialization. 5276 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 5277 5278 // FIXME: Poor source location information. 5279 InitializationKind Kind 5280 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 5281 Init->getLocStart(), 5282 Init->getLocEnd()) 5283 : InitializationKind::CreateCopy(VDecl->getLocation(), 5284 Init->getLocStart()); 5285 5286 // Get the decls type and save a reference for later, since 5287 // CheckInitializerTypes may change it. 5288 QualType DclT = VDecl->getType(), SavT = DclT; 5289 if (VDecl->isLocalVarDecl()) { 5290 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 5291 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 5292 VDecl->setInvalidDecl(); 5293 } else if (!VDecl->isInvalidDecl()) { 5294 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5295 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5296 MultiExprArg(*this, &Init, 1), 5297 &DclT); 5298 if (Result.isInvalid()) { 5299 VDecl->setInvalidDecl(); 5300 return; 5301 } 5302 5303 Init = Result.takeAs<Expr>(); 5304 5305 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 5306 // Don't check invalid declarations to avoid emitting useless diagnostics. 5307 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 5308 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 5309 CheckForConstantInitializer(Init, DclT); 5310 } 5311 } 5312 } else if (VDecl->isStaticDataMember() && 5313 VDecl->getLexicalDeclContext()->isRecord()) { 5314 // This is an in-class initialization for a static data member, e.g., 5315 // 5316 // struct S { 5317 // static const int value = 17; 5318 // }; 5319 5320 // Try to perform the initialization regardless. 5321 if (!VDecl->isInvalidDecl()) { 5322 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5323 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5324 MultiExprArg(*this, &Init, 1), 5325 &DclT); 5326 if (Result.isInvalid()) { 5327 VDecl->setInvalidDecl(); 5328 return; 5329 } 5330 5331 Init = Result.takeAs<Expr>(); 5332 } 5333 5334 // C++ [class.mem]p4: 5335 // A member-declarator can contain a constant-initializer only 5336 // if it declares a static member (9.4) of const integral or 5337 // const enumeration type, see 9.4.2. 5338 QualType T = VDecl->getType(); 5339 5340 // Do nothing on dependent types. 5341 if (T->isDependentType()) { 5342 5343 // Require constness. 5344 } else if (!T.isConstQualified()) { 5345 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 5346 << Init->getSourceRange(); 5347 VDecl->setInvalidDecl(); 5348 5349 // We allow integer constant expressions in all cases. 5350 } else if (T->isIntegralOrEnumerationType()) { 5351 if (!Init->isValueDependent()) { 5352 // Check whether the expression is a constant expression. 5353 llvm::APSInt Value; 5354 SourceLocation Loc; 5355 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 5356 Diag(Loc, diag::err_in_class_initializer_non_constant) 5357 << Init->getSourceRange(); 5358 VDecl->setInvalidDecl(); 5359 } 5360 } 5361 5362 // We allow floating-point constants as an extension in C++03, and 5363 // C++0x has far more complicated rules that we don't really 5364 // implement fully. 5365 } else { 5366 bool Allowed = false; 5367 if (getLangOptions().CPlusPlus0x) { 5368 Allowed = T->isLiteralType(); 5369 } else if (T->isFloatingType()) { // also permits complex, which is ok 5370 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 5371 << T << Init->getSourceRange(); 5372 Allowed = true; 5373 } 5374 5375 if (!Allowed) { 5376 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 5377 << T << Init->getSourceRange(); 5378 VDecl->setInvalidDecl(); 5379 5380 // TODO: there are probably expressions that pass here that shouldn't. 5381 } else if (!Init->isValueDependent() && 5382 !Init->isConstantInitializer(Context, false)) { 5383 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 5384 << Init->getSourceRange(); 5385 VDecl->setInvalidDecl(); 5386 } 5387 } 5388 } else if (VDecl->isFileVarDecl()) { 5389 if (VDecl->getStorageClassAsWritten() == SC_Extern && 5390 (!getLangOptions().CPlusPlus || 5391 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 5392 Diag(VDecl->getLocation(), diag::warn_extern_init); 5393 if (!VDecl->isInvalidDecl()) { 5394 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5395 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5396 MultiExprArg(*this, &Init, 1), 5397 &DclT); 5398 if (Result.isInvalid()) { 5399 VDecl->setInvalidDecl(); 5400 return; 5401 } 5402 5403 Init = Result.takeAs<Expr>(); 5404 } 5405 5406 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 5407 // Don't check invalid declarations to avoid emitting useless diagnostics. 5408 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 5409 // C99 6.7.8p4. All file scoped initializers need to be constant. 5410 CheckForConstantInitializer(Init, DclT); 5411 } 5412 } 5413 // If the type changed, it means we had an incomplete type that was 5414 // completed by the initializer. For example: 5415 // int ary[] = { 1, 3, 5 }; 5416 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 5417 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 5418 VDecl->setType(DclT); 5419 Init->setType(DclT); 5420 } 5421 5422 5423 // If this variable is a local declaration with record type, make sure it 5424 // doesn't have a flexible member initialization. We only support this as a 5425 // global/static definition. 5426 if (VDecl->hasLocalStorage()) 5427 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 5428 if (RT->getDecl()->hasFlexibleArrayMember()) { 5429 // Check whether the initializer tries to initialize the flexible 5430 // array member itself to anything other than an empty initializer list. 5431 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 5432 unsigned Index = std::distance(RT->getDecl()->field_begin(), 5433 RT->getDecl()->field_end()) - 1; 5434 if (Index < ILE->getNumInits() && 5435 !(isa<InitListExpr>(ILE->getInit(Index)) && 5436 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 5437 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 5438 VDecl->setInvalidDecl(); 5439 } 5440 } 5441 } 5442 5443 // Check any implicit conversions within the expression. 5444 CheckImplicitConversions(Init, VDecl->getLocation()); 5445 5446 Init = MaybeCreateExprWithCleanups(Init); 5447 // Attach the initializer to the decl. 5448 VDecl->setInit(Init); 5449 5450 CheckCompleteVariableDeclaration(VDecl); 5451} 5452 5453/// ActOnInitializerError - Given that there was an error parsing an 5454/// initializer for the given declaration, try to return to some form 5455/// of sanity. 5456void Sema::ActOnInitializerError(Decl *D) { 5457 // Our main concern here is re-establishing invariants like "a 5458 // variable's type is either dependent or complete". 5459 if (!D || D->isInvalidDecl()) return; 5460 5461 VarDecl *VD = dyn_cast<VarDecl>(D); 5462 if (!VD) return; 5463 5464 // Auto types are meaningless if we can't make sense of the initializer. 5465 if (ParsingInitForAutoVars.count(D)) { 5466 D->setInvalidDecl(); 5467 return; 5468 } 5469 5470 QualType Ty = VD->getType(); 5471 if (Ty->isDependentType()) return; 5472 5473 // Require a complete type. 5474 if (RequireCompleteType(VD->getLocation(), 5475 Context.getBaseElementType(Ty), 5476 diag::err_typecheck_decl_incomplete_type)) { 5477 VD->setInvalidDecl(); 5478 return; 5479 } 5480 5481 // Require an abstract type. 5482 if (RequireNonAbstractType(VD->getLocation(), Ty, 5483 diag::err_abstract_type_in_decl, 5484 AbstractVariableType)) { 5485 VD->setInvalidDecl(); 5486 return; 5487 } 5488 5489 // Don't bother complaining about constructors or destructors, 5490 // though. 5491} 5492 5493void Sema::ActOnUninitializedDecl(Decl *RealDecl, 5494 bool TypeMayContainAuto) { 5495 // If there is no declaration, there was an error parsing it. Just ignore it. 5496 if (RealDecl == 0) 5497 return; 5498 5499 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 5500 QualType Type = Var->getType(); 5501 5502 // C++0x [dcl.spec.auto]p3 5503 if (TypeMayContainAuto && Type->getContainedAutoType()) { 5504 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 5505 << Var->getDeclName() << Type; 5506 Var->setInvalidDecl(); 5507 return; 5508 } 5509 5510 switch (Var->isThisDeclarationADefinition()) { 5511 case VarDecl::Definition: 5512 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 5513 break; 5514 5515 // We have an out-of-line definition of a static data member 5516 // that has an in-class initializer, so we type-check this like 5517 // a declaration. 5518 // 5519 // Fall through 5520 5521 case VarDecl::DeclarationOnly: 5522 // It's only a declaration. 5523 5524 // Block scope. C99 6.7p7: If an identifier for an object is 5525 // declared with no linkage (C99 6.2.2p6), the type for the 5526 // object shall be complete. 5527 if (!Type->isDependentType() && Var->isLocalVarDecl() && 5528 !Var->getLinkage() && !Var->isInvalidDecl() && 5529 RequireCompleteType(Var->getLocation(), Type, 5530 diag::err_typecheck_decl_incomplete_type)) 5531 Var->setInvalidDecl(); 5532 5533 // Make sure that the type is not abstract. 5534 if (!Type->isDependentType() && !Var->isInvalidDecl() && 5535 RequireNonAbstractType(Var->getLocation(), Type, 5536 diag::err_abstract_type_in_decl, 5537 AbstractVariableType)) 5538 Var->setInvalidDecl(); 5539 return; 5540 5541 case VarDecl::TentativeDefinition: 5542 // File scope. C99 6.9.2p2: A declaration of an identifier for an 5543 // object that has file scope without an initializer, and without a 5544 // storage-class specifier or with the storage-class specifier "static", 5545 // constitutes a tentative definition. Note: A tentative definition with 5546 // external linkage is valid (C99 6.2.2p5). 5547 if (!Var->isInvalidDecl()) { 5548 if (const IncompleteArrayType *ArrayT 5549 = Context.getAsIncompleteArrayType(Type)) { 5550 if (RequireCompleteType(Var->getLocation(), 5551 ArrayT->getElementType(), 5552 diag::err_illegal_decl_array_incomplete_type)) 5553 Var->setInvalidDecl(); 5554 } else if (Var->getStorageClass() == SC_Static) { 5555 // C99 6.9.2p3: If the declaration of an identifier for an object is 5556 // a tentative definition and has internal linkage (C99 6.2.2p3), the 5557 // declared type shall not be an incomplete type. 5558 // NOTE: code such as the following 5559 // static struct s; 5560 // struct s { int a; }; 5561 // is accepted by gcc. Hence here we issue a warning instead of 5562 // an error and we do not invalidate the static declaration. 5563 // NOTE: to avoid multiple warnings, only check the first declaration. 5564 if (Var->getPreviousDeclaration() == 0) 5565 RequireCompleteType(Var->getLocation(), Type, 5566 diag::ext_typecheck_decl_incomplete_type); 5567 } 5568 } 5569 5570 // Record the tentative definition; we're done. 5571 if (!Var->isInvalidDecl()) 5572 TentativeDefinitions.push_back(Var); 5573 return; 5574 } 5575 5576 // Provide a specific diagnostic for uninitialized variable 5577 // definitions with incomplete array type. 5578 if (Type->isIncompleteArrayType()) { 5579 Diag(Var->getLocation(), 5580 diag::err_typecheck_incomplete_array_needs_initializer); 5581 Var->setInvalidDecl(); 5582 return; 5583 } 5584 5585 // Provide a specific diagnostic for uninitialized variable 5586 // definitions with reference type. 5587 if (Type->isReferenceType()) { 5588 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 5589 << Var->getDeclName() 5590 << SourceRange(Var->getLocation(), Var->getLocation()); 5591 Var->setInvalidDecl(); 5592 return; 5593 } 5594 5595 // Do not attempt to type-check the default initializer for a 5596 // variable with dependent type. 5597 if (Type->isDependentType()) 5598 return; 5599 5600 if (Var->isInvalidDecl()) 5601 return; 5602 5603 if (RequireCompleteType(Var->getLocation(), 5604 Context.getBaseElementType(Type), 5605 diag::err_typecheck_decl_incomplete_type)) { 5606 Var->setInvalidDecl(); 5607 return; 5608 } 5609 5610 // The variable can not have an abstract class type. 5611 if (RequireNonAbstractType(Var->getLocation(), Type, 5612 diag::err_abstract_type_in_decl, 5613 AbstractVariableType)) { 5614 Var->setInvalidDecl(); 5615 return; 5616 } 5617 5618 const RecordType *Record 5619 = Context.getBaseElementType(Type)->getAs<RecordType>(); 5620 if (Record && getLangOptions().CPlusPlus && 5621 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 5622 // C++03 [dcl.init]p9: 5623 // If no initializer is specified for an object, and the 5624 // object is of (possibly cv-qualified) non-POD class type (or 5625 // array thereof), the object shall be default-initialized; if 5626 // the object is of const-qualified type, the underlying class 5627 // type shall have a user-declared default 5628 // constructor. Otherwise, if no initializer is specified for 5629 // a non- static object, the object and its subobjects, if 5630 // any, have an indeterminate initial value); if the object 5631 // or any of its subobjects are of const-qualified type, the 5632 // program is ill-formed. 5633 } else { 5634 // Check for jumps past the implicit initializer. C++0x 5635 // clarifies that this applies to a "variable with automatic 5636 // storage duration", not a "local variable". 5637 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 5638 getCurFunction()->setHasBranchProtectedScope(); 5639 5640 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 5641 InitializationKind Kind 5642 = InitializationKind::CreateDefault(Var->getLocation()); 5643 5644 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 5645 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 5646 MultiExprArg(*this, 0, 0)); 5647 if (Init.isInvalid()) 5648 Var->setInvalidDecl(); 5649 else if (Init.get()) 5650 Var->setInit(MaybeCreateExprWithCleanups(Init.get())); 5651 } 5652 5653 CheckCompleteVariableDeclaration(Var); 5654 } 5655} 5656 5657void Sema::ActOnCXXForRangeDecl(Decl *D) { 5658 VarDecl *VD = dyn_cast<VarDecl>(D); 5659 if (!VD) { 5660 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var); 5661 D->setInvalidDecl(); 5662 return; 5663 } 5664 5665 VD->setCXXForRangeDecl(true); 5666 5667 // for-range-declaration cannot be given a storage class specifier. 5668 int Error = -1; 5669 switch (VD->getStorageClassAsWritten()) { 5670 case SC_None: 5671 break; 5672 case SC_Extern: 5673 Error = 0; 5674 break; 5675 case SC_Static: 5676 Error = 1; 5677 break; 5678 case SC_PrivateExtern: 5679 Error = 2; 5680 break; 5681 case SC_Auto: 5682 Error = 3; 5683 break; 5684 case SC_Register: 5685 Error = 4; 5686 break; 5687 } 5688 // FIXME: constexpr isn't allowed here. 5689 //if (DS.isConstexprSpecified()) 5690 // Error = 5; 5691 if (Error != -1) { 5692 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class) 5693 << VD->getDeclName() << Error; 5694 D->setInvalidDecl(); 5695 } 5696} 5697 5698void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { 5699 if (var->isInvalidDecl()) return; 5700 5701 // All the following checks are C++ only. 5702 if (!getLangOptions().CPlusPlus) return; 5703 5704 QualType baseType = Context.getBaseElementType(var->getType()); 5705 if (baseType->isDependentType()) return; 5706 5707 // __block variables might require us to capture a copy-initializer. 5708 if (var->hasAttr<BlocksAttr>()) { 5709 // It's currently invalid to ever have a __block variable with an 5710 // array type; should we diagnose that here? 5711 5712 // Regardless, we don't want to ignore array nesting when 5713 // constructing this copy. 5714 QualType type = var->getType(); 5715 5716 if (type->isStructureOrClassType()) { 5717 SourceLocation poi = var->getLocation(); 5718 Expr *varRef = new (Context) DeclRefExpr(var, type, VK_LValue, poi); 5719 ExprResult result = 5720 PerformCopyInitialization( 5721 InitializedEntity::InitializeBlock(poi, type, false), 5722 poi, Owned(varRef)); 5723 if (!result.isInvalid()) { 5724 result = MaybeCreateExprWithCleanups(result); 5725 Expr *init = result.takeAs<Expr>(); 5726 Context.setBlockVarCopyInits(var, init); 5727 } 5728 } 5729 } 5730 5731 // Check for global constructors. 5732 if (!var->getDeclContext()->isDependentContext() && 5733 var->hasGlobalStorage() && 5734 !var->isStaticLocal() && 5735 var->getInit() && 5736 !var->getInit()->isConstantInitializer(Context, 5737 baseType->isReferenceType())) 5738 Diag(var->getLocation(), diag::warn_global_constructor) 5739 << var->getInit()->getSourceRange(); 5740 5741 // Require the destructor. 5742 if (const RecordType *recordType = baseType->getAs<RecordType>()) 5743 FinalizeVarWithDestructor(var, recordType); 5744} 5745 5746/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform 5747/// any semantic actions necessary after any initializer has been attached. 5748void 5749Sema::FinalizeDeclaration(Decl *ThisDecl) { 5750 // Note that we are no longer parsing the initializer for this declaration. 5751 ParsingInitForAutoVars.erase(ThisDecl); 5752} 5753 5754Sema::DeclGroupPtrTy 5755Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 5756 Decl **Group, unsigned NumDecls) { 5757 llvm::SmallVector<Decl*, 8> Decls; 5758 5759 if (DS.isTypeSpecOwned()) 5760 Decls.push_back(DS.getRepAsDecl()); 5761 5762 for (unsigned i = 0; i != NumDecls; ++i) 5763 if (Decl *D = Group[i]) 5764 Decls.push_back(D); 5765 5766 return BuildDeclaratorGroup(Decls.data(), Decls.size(), 5767 DS.getTypeSpecType() == DeclSpec::TST_auto); 5768} 5769 5770/// BuildDeclaratorGroup - convert a list of declarations into a declaration 5771/// group, performing any necessary semantic checking. 5772Sema::DeclGroupPtrTy 5773Sema::BuildDeclaratorGroup(Decl **Group, unsigned NumDecls, 5774 bool TypeMayContainAuto) { 5775 // C++0x [dcl.spec.auto]p7: 5776 // If the type deduced for the template parameter U is not the same in each 5777 // deduction, the program is ill-formed. 5778 // FIXME: When initializer-list support is added, a distinction is needed 5779 // between the deduced type U and the deduced type which 'auto' stands for. 5780 // auto a = 0, b = { 1, 2, 3 }; 5781 // is legal because the deduced type U is 'int' in both cases. 5782 if (TypeMayContainAuto && NumDecls > 1) { 5783 QualType Deduced; 5784 CanQualType DeducedCanon; 5785 VarDecl *DeducedDecl = 0; 5786 for (unsigned i = 0; i != NumDecls; ++i) { 5787 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { 5788 AutoType *AT = D->getType()->getContainedAutoType(); 5789 // Don't reissue diagnostics when instantiating a template. 5790 if (AT && D->isInvalidDecl()) 5791 break; 5792 if (AT && AT->isDeduced()) { 5793 QualType U = AT->getDeducedType(); 5794 CanQualType UCanon = Context.getCanonicalType(U); 5795 if (Deduced.isNull()) { 5796 Deduced = U; 5797 DeducedCanon = UCanon; 5798 DeducedDecl = D; 5799 } else if (DeducedCanon != UCanon) { 5800 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), 5801 diag::err_auto_different_deductions) 5802 << Deduced << DeducedDecl->getDeclName() 5803 << U << D->getDeclName() 5804 << DeducedDecl->getInit()->getSourceRange() 5805 << D->getInit()->getSourceRange(); 5806 D->setInvalidDecl(); 5807 break; 5808 } 5809 } 5810 } 5811 } 5812 } 5813 5814 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, NumDecls)); 5815} 5816 5817 5818/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 5819/// to introduce parameters into function prototype scope. 5820Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 5821 const DeclSpec &DS = D.getDeclSpec(); 5822 5823 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 5824 VarDecl::StorageClass StorageClass = SC_None; 5825 VarDecl::StorageClass StorageClassAsWritten = SC_None; 5826 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 5827 StorageClass = SC_Register; 5828 StorageClassAsWritten = SC_Register; 5829 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 5830 Diag(DS.getStorageClassSpecLoc(), 5831 diag::err_invalid_storage_class_in_func_decl); 5832 D.getMutableDeclSpec().ClearStorageClassSpecs(); 5833 } 5834 5835 if (D.getDeclSpec().isThreadSpecified()) 5836 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5837 5838 DiagnoseFunctionSpecifiers(D); 5839 5840 TagDecl *OwnedDecl = 0; 5841 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 5842 QualType parmDeclType = TInfo->getType(); 5843 5844 if (getLangOptions().CPlusPlus) { 5845 // Check that there are no default arguments inside the type of this 5846 // parameter. 5847 CheckExtraCXXDefaultArguments(D); 5848 5849 if (OwnedDecl && OwnedDecl->isDefinition()) { 5850 // C++ [dcl.fct]p6: 5851 // Types shall not be defined in return or parameter types. 5852 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 5853 << Context.getTypeDeclType(OwnedDecl); 5854 } 5855 5856 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 5857 if (D.getCXXScopeSpec().isSet()) { 5858 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 5859 << D.getCXXScopeSpec().getRange(); 5860 D.getCXXScopeSpec().clear(); 5861 } 5862 } 5863 5864 // Ensure we have a valid name 5865 IdentifierInfo *II = 0; 5866 if (D.hasName()) { 5867 II = D.getIdentifier(); 5868 if (!II) { 5869 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) 5870 << GetNameForDeclarator(D).getName().getAsString(); 5871 D.setInvalidType(true); 5872 } 5873 } 5874 5875 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 5876 if (II) { 5877 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 5878 ForRedeclaration); 5879 LookupName(R, S); 5880 if (R.isSingleResult()) { 5881 NamedDecl *PrevDecl = R.getFoundDecl(); 5882 if (PrevDecl->isTemplateParameter()) { 5883 // Maybe we will complain about the shadowed template parameter. 5884 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5885 // Just pretend that we didn't see the previous declaration. 5886 PrevDecl = 0; 5887 } else if (S->isDeclScope(PrevDecl)) { 5888 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 5889 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5890 5891 // Recover by removing the name 5892 II = 0; 5893 D.SetIdentifier(0, D.getIdentifierLoc()); 5894 D.setInvalidType(true); 5895 } 5896 } 5897 } 5898 5899 // Temporarily put parameter variables in the translation unit, not 5900 // the enclosing context. This prevents them from accidentally 5901 // looking like class members in C++. 5902 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 5903 D.getSourceRange().getBegin(), 5904 D.getIdentifierLoc(), II, 5905 parmDeclType, TInfo, 5906 StorageClass, StorageClassAsWritten); 5907 5908 if (D.isInvalidType()) 5909 New->setInvalidDecl(); 5910 5911 assert(S->isFunctionPrototypeScope()); 5912 assert(S->getFunctionPrototypeDepth() >= 1); 5913 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1, 5914 S->getNextFunctionPrototypeIndex()); 5915 5916 // Add the parameter declaration into this scope. 5917 S->AddDecl(New); 5918 if (II) 5919 IdResolver.AddDecl(New); 5920 5921 ProcessDeclAttributes(S, New, D); 5922 5923 if (New->hasAttr<BlocksAttr>()) { 5924 Diag(New->getLocation(), diag::err_block_on_nonlocal); 5925 } 5926 return New; 5927} 5928 5929/// \brief Synthesizes a variable for a parameter arising from a 5930/// typedef. 5931ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 5932 SourceLocation Loc, 5933 QualType T) { 5934 /* FIXME: setting StartLoc == Loc. 5935 Would it be worth to modify callers so as to provide proper source 5936 location for the unnamed parameters, embedding the parameter's type? */ 5937 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, 0, 5938 T, Context.getTrivialTypeSourceInfo(T, Loc), 5939 SC_None, SC_None, 0); 5940 Param->setImplicit(); 5941 return Param; 5942} 5943 5944void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 5945 ParmVarDecl * const *ParamEnd) { 5946 // Don't diagnose unused-parameter errors in template instantiations; we 5947 // will already have done so in the template itself. 5948 if (!ActiveTemplateInstantiations.empty()) 5949 return; 5950 5951 for (; Param != ParamEnd; ++Param) { 5952 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 5953 !(*Param)->hasAttr<UnusedAttr>()) { 5954 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 5955 << (*Param)->getDeclName(); 5956 } 5957 } 5958} 5959 5960void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, 5961 ParmVarDecl * const *ParamEnd, 5962 QualType ReturnTy, 5963 NamedDecl *D) { 5964 if (LangOpts.NumLargeByValueCopy == 0) // No check. 5965 return; 5966 5967 // Warn if the return value is pass-by-value and larger than the specified 5968 // threshold. 5969 if (ReturnTy->isPODType()) { 5970 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); 5971 if (Size > LangOpts.NumLargeByValueCopy) 5972 Diag(D->getLocation(), diag::warn_return_value_size) 5973 << D->getDeclName() << Size; 5974 } 5975 5976 // Warn if any parameter is pass-by-value and larger than the specified 5977 // threshold. 5978 for (; Param != ParamEnd; ++Param) { 5979 QualType T = (*Param)->getType(); 5980 if (!T->isPODType()) 5981 continue; 5982 unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); 5983 if (Size > LangOpts.NumLargeByValueCopy) 5984 Diag((*Param)->getLocation(), diag::warn_parameter_size) 5985 << (*Param)->getDeclName() << Size; 5986 } 5987} 5988 5989ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc, 5990 SourceLocation NameLoc, IdentifierInfo *Name, 5991 QualType T, TypeSourceInfo *TSInfo, 5992 VarDecl::StorageClass StorageClass, 5993 VarDecl::StorageClass StorageClassAsWritten) { 5994 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name, 5995 adjustParameterType(T), TSInfo, 5996 StorageClass, StorageClassAsWritten, 5997 0); 5998 5999 // Parameters can not be abstract class types. 6000 // For record types, this is done by the AbstractClassUsageDiagnoser once 6001 // the class has been completely parsed. 6002 if (!CurContext->isRecord() && 6003 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 6004 AbstractParamType)) 6005 New->setInvalidDecl(); 6006 6007 // Parameter declarators cannot be interface types. All ObjC objects are 6008 // passed by reference. 6009 if (T->isObjCObjectType()) { 6010 Diag(NameLoc, 6011 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 6012 New->setInvalidDecl(); 6013 } 6014 6015 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 6016 // duration shall not be qualified by an address-space qualifier." 6017 // Since all parameters have automatic store duration, they can not have 6018 // an address space. 6019 if (T.getAddressSpace() != 0) { 6020 Diag(NameLoc, diag::err_arg_with_address_space); 6021 New->setInvalidDecl(); 6022 } 6023 6024 return New; 6025} 6026 6027void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 6028 SourceLocation LocAfterDecls) { 6029 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 6030 6031 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 6032 // for a K&R function. 6033 if (!FTI.hasPrototype) { 6034 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 6035 --i; 6036 if (FTI.ArgInfo[i].Param == 0) { 6037 llvm::SmallString<256> Code; 6038 llvm::raw_svector_ostream(Code) << " int " 6039 << FTI.ArgInfo[i].Ident->getName() 6040 << ";\n"; 6041 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 6042 << FTI.ArgInfo[i].Ident 6043 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 6044 6045 // Implicitly declare the argument as type 'int' for lack of a better 6046 // type. 6047 AttributeFactory attrs; 6048 DeclSpec DS(attrs); 6049 const char* PrevSpec; // unused 6050 unsigned DiagID; // unused 6051 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 6052 PrevSpec, DiagID); 6053 Declarator ParamD(DS, Declarator::KNRTypeListContext); 6054 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 6055 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 6056 } 6057 } 6058 } 6059} 6060 6061Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 6062 Declarator &D) { 6063 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 6064 assert(D.isFunctionDeclarator() && "Not a function declarator!"); 6065 Scope *ParentScope = FnBodyScope->getParent(); 6066 6067 Decl *DP = HandleDeclarator(ParentScope, D, 6068 MultiTemplateParamsArg(*this), 6069 /*IsFunctionDefinition=*/true); 6070 return ActOnStartOfFunctionDef(FnBodyScope, DP); 6071} 6072 6073static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 6074 // Don't warn about invalid declarations. 6075 if (FD->isInvalidDecl()) 6076 return false; 6077 6078 // Or declarations that aren't global. 6079 if (!FD->isGlobal()) 6080 return false; 6081 6082 // Don't warn about C++ member functions. 6083 if (isa<CXXMethodDecl>(FD)) 6084 return false; 6085 6086 // Don't warn about 'main'. 6087 if (FD->isMain()) 6088 return false; 6089 6090 // Don't warn about inline functions. 6091 if (FD->isInlined()) 6092 return false; 6093 6094 // Don't warn about function templates. 6095 if (FD->getDescribedFunctionTemplate()) 6096 return false; 6097 6098 // Don't warn about function template specializations. 6099 if (FD->isFunctionTemplateSpecialization()) 6100 return false; 6101 6102 bool MissingPrototype = true; 6103 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 6104 Prev; Prev = Prev->getPreviousDeclaration()) { 6105 // Ignore any declarations that occur in function or method 6106 // scope, because they aren't visible from the header. 6107 if (Prev->getDeclContext()->isFunctionOrMethod()) 6108 continue; 6109 6110 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 6111 break; 6112 } 6113 6114 return MissingPrototype; 6115} 6116 6117void Sema::CheckForFunctionRedefinition(FunctionDecl *FD) { 6118 // Don't complain if we're in GNU89 mode and the previous definition 6119 // was an extern inline function. 6120 const FunctionDecl *Definition; 6121 if (FD->hasBody(Definition) && 6122 !canRedefineFunction(Definition, getLangOptions())) { 6123 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 6124 Definition->getStorageClass() == SC_Extern) 6125 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 6126 << FD->getDeclName() << getLangOptions().CPlusPlus; 6127 else 6128 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 6129 Diag(Definition->getLocation(), diag::note_previous_definition); 6130 } 6131} 6132 6133Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 6134 // Clear the last template instantiation error context. 6135 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 6136 6137 if (!D) 6138 return D; 6139 FunctionDecl *FD = 0; 6140 6141 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 6142 FD = FunTmpl->getTemplatedDecl(); 6143 else 6144 FD = cast<FunctionDecl>(D); 6145 6146 // Enter a new function scope 6147 PushFunctionScope(); 6148 6149 // See if this is a redefinition. 6150 if (!FD->isLateTemplateParsed()) 6151 CheckForFunctionRedefinition(FD); 6152 6153 // Builtin functions cannot be defined. 6154 if (unsigned BuiltinID = FD->getBuiltinID()) { 6155 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 6156 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 6157 FD->setInvalidDecl(); 6158 } 6159 } 6160 6161 // The return type of a function definition must be complete 6162 // (C99 6.9.1p3, C++ [dcl.fct]p6). 6163 QualType ResultType = FD->getResultType(); 6164 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 6165 !FD->isInvalidDecl() && 6166 RequireCompleteType(FD->getLocation(), ResultType, 6167 diag::err_func_def_incomplete_result)) 6168 FD->setInvalidDecl(); 6169 6170 // GNU warning -Wmissing-prototypes: 6171 // Warn if a global function is defined without a previous 6172 // prototype declaration. This warning is issued even if the 6173 // definition itself provides a prototype. The aim is to detect 6174 // global functions that fail to be declared in header files. 6175 if (ShouldWarnAboutMissingPrototype(FD)) 6176 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 6177 6178 if (FnBodyScope) 6179 PushDeclContext(FnBodyScope, FD); 6180 6181 // Check the validity of our function parameters 6182 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), 6183 /*CheckParameterNames=*/true); 6184 6185 // Introduce our parameters into the function scope 6186 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 6187 ParmVarDecl *Param = FD->getParamDecl(p); 6188 Param->setOwningFunction(FD); 6189 6190 // If this has an identifier, add it to the scope stack. 6191 if (Param->getIdentifier() && FnBodyScope) { 6192 CheckShadow(FnBodyScope, Param); 6193 6194 PushOnScopeChains(Param, FnBodyScope); 6195 } 6196 } 6197 6198 // Checking attributes of current function definition 6199 // dllimport attribute. 6200 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 6201 if (DA && (!FD->getAttr<DLLExportAttr>())) { 6202 // dllimport attribute cannot be directly applied to definition. 6203 // Microsoft accepts dllimport for functions defined within class scope. 6204 if (!DA->isInherited() && 6205 !(LangOpts.Microsoft && FD->getLexicalDeclContext()->isRecord())) { 6206 Diag(FD->getLocation(), 6207 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 6208 << "dllimport"; 6209 FD->setInvalidDecl(); 6210 return FD; 6211 } 6212 6213 // Visual C++ appears to not think this is an issue, so only issue 6214 // a warning when Microsoft extensions are disabled. 6215 if (!LangOpts.Microsoft) { 6216 // If a symbol previously declared dllimport is later defined, the 6217 // attribute is ignored in subsequent references, and a warning is 6218 // emitted. 6219 Diag(FD->getLocation(), 6220 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 6221 << FD->getName() << "dllimport"; 6222 } 6223 } 6224 return FD; 6225} 6226 6227/// \brief Given the set of return statements within a function body, 6228/// compute the variables that are subject to the named return value 6229/// optimization. 6230/// 6231/// Each of the variables that is subject to the named return value 6232/// optimization will be marked as NRVO variables in the AST, and any 6233/// return statement that has a marked NRVO variable as its NRVO candidate can 6234/// use the named return value optimization. 6235/// 6236/// This function applies a very simplistic algorithm for NRVO: if every return 6237/// statement in the function has the same NRVO candidate, that candidate is 6238/// the NRVO variable. 6239/// 6240/// FIXME: Employ a smarter algorithm that accounts for multiple return 6241/// statements and the lifetimes of the NRVO candidates. We should be able to 6242/// find a maximal set of NRVO variables. 6243static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 6244 ReturnStmt **Returns = Scope->Returns.data(); 6245 6246 const VarDecl *NRVOCandidate = 0; 6247 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 6248 if (!Returns[I]->getNRVOCandidate()) 6249 return; 6250 6251 if (!NRVOCandidate) 6252 NRVOCandidate = Returns[I]->getNRVOCandidate(); 6253 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 6254 return; 6255 } 6256 6257 if (NRVOCandidate) 6258 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 6259} 6260 6261Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 6262 return ActOnFinishFunctionBody(D, move(BodyArg), false); 6263} 6264 6265Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 6266 bool IsInstantiation) { 6267 FunctionDecl *FD = 0; 6268 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 6269 if (FunTmpl) 6270 FD = FunTmpl->getTemplatedDecl(); 6271 else 6272 FD = dyn_cast_or_null<FunctionDecl>(dcl); 6273 6274 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 6275 sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; 6276 6277 if (FD) { 6278 FD->setBody(Body); 6279 if (FD->isMain()) { 6280 // C and C++ allow for main to automagically return 0. 6281 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 6282 FD->setHasImplicitReturnZero(true); 6283 WP.disableCheckFallThrough(); 6284 } 6285 6286 if (!FD->isInvalidDecl()) { 6287 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 6288 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), 6289 FD->getResultType(), FD); 6290 6291 // If this is a constructor, we need a vtable. 6292 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 6293 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 6294 6295 ComputeNRVO(Body, getCurFunction()); 6296 } 6297 6298 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 6299 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 6300 assert(MD == getCurMethodDecl() && "Method parsing confused"); 6301 MD->setBody(Body); 6302 if (Body) 6303 MD->setEndLoc(Body->getLocEnd()); 6304 if (!MD->isInvalidDecl()) { 6305 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 6306 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), 6307 MD->getResultType(), MD); 6308 } 6309 } else { 6310 return 0; 6311 } 6312 6313 // Verify and clean out per-function state. 6314 if (Body) { 6315 // C++ constructors that have function-try-blocks can't have return 6316 // statements in the handlers of that block. (C++ [except.handle]p14) 6317 // Verify this. 6318 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 6319 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 6320 6321 // Verify that that gotos and switch cases don't jump into scopes illegally. 6322 // Verify that that gotos and switch cases don't jump into scopes illegally. 6323 if (getCurFunction()->NeedsScopeChecking() && 6324 !dcl->isInvalidDecl() && 6325 !hasAnyErrorsInThisFunction()) 6326 DiagnoseInvalidJumps(Body); 6327 6328 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 6329 if (!Destructor->getParent()->isDependentType()) 6330 CheckDestructor(Destructor); 6331 6332 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 6333 Destructor->getParent()); 6334 } 6335 6336 // If any errors have occurred, clear out any temporaries that may have 6337 // been leftover. This ensures that these temporaries won't be picked up for 6338 // deletion in some later function. 6339 if (PP.getDiagnostics().hasErrorOccurred() || 6340 PP.getDiagnostics().getSuppressAllDiagnostics()) 6341 ExprTemporaries.clear(); 6342 else if (!isa<FunctionTemplateDecl>(dcl)) { 6343 // Since the body is valid, issue any analysis-based warnings that are 6344 // enabled. 6345 ActivePolicy = &WP; 6346 } 6347 6348 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 6349 } 6350 6351 if (!IsInstantiation) 6352 PopDeclContext(); 6353 6354 PopFunctionOrBlockScope(ActivePolicy, dcl); 6355 6356 // If any errors have occurred, clear out any temporaries that may have 6357 // been leftover. This ensures that these temporaries won't be picked up for 6358 // deletion in some later function. 6359 if (getDiagnostics().hasErrorOccurred()) 6360 ExprTemporaries.clear(); 6361 6362 return dcl; 6363} 6364 6365/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 6366/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 6367NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 6368 IdentifierInfo &II, Scope *S) { 6369 // Before we produce a declaration for an implicitly defined 6370 // function, see whether there was a locally-scoped declaration of 6371 // this name as a function or variable. If so, use that 6372 // (non-visible) declaration, and complain about it. 6373 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 6374 = LocallyScopedExternalDecls.find(&II); 6375 if (Pos != LocallyScopedExternalDecls.end()) { 6376 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 6377 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 6378 return Pos->second; 6379 } 6380 6381 // Extension in C99. Legal in C90, but warn about it. 6382 if (II.getName().startswith("__builtin_")) 6383 Diag(Loc, diag::warn_builtin_unknown) << &II; 6384 else if (getLangOptions().C99) 6385 Diag(Loc, diag::ext_implicit_function_decl) << &II; 6386 else 6387 Diag(Loc, diag::warn_implicit_function_decl) << &II; 6388 6389 // Set a Declarator for the implicit definition: int foo(); 6390 const char *Dummy; 6391 AttributeFactory attrFactory; 6392 DeclSpec DS(attrFactory); 6393 unsigned DiagID; 6394 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 6395 (void)Error; // Silence warning. 6396 assert(!Error && "Error setting up implicit decl!"); 6397 Declarator D(DS, Declarator::BlockContext); 6398 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 6399 0, 0, true, SourceLocation(), 6400 EST_None, SourceLocation(), 6401 0, 0, 0, 0, Loc, Loc, D), 6402 DS.getAttributes(), 6403 SourceLocation()); 6404 D.SetIdentifier(&II, Loc); 6405 6406 // Insert this function into translation-unit scope. 6407 6408 DeclContext *PrevDC = CurContext; 6409 CurContext = Context.getTranslationUnitDecl(); 6410 6411 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 6412 FD->setImplicit(); 6413 6414 CurContext = PrevDC; 6415 6416 AddKnownFunctionAttributes(FD); 6417 6418 return FD; 6419} 6420 6421/// \brief Adds any function attributes that we know a priori based on 6422/// the declaration of this function. 6423/// 6424/// These attributes can apply both to implicitly-declared builtins 6425/// (like __builtin___printf_chk) or to library-declared functions 6426/// like NSLog or printf. 6427void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 6428 if (FD->isInvalidDecl()) 6429 return; 6430 6431 // If this is a built-in function, map its builtin attributes to 6432 // actual attributes. 6433 if (unsigned BuiltinID = FD->getBuiltinID()) { 6434 // Handle printf-formatting attributes. 6435 unsigned FormatIdx; 6436 bool HasVAListArg; 6437 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 6438 if (!FD->getAttr<FormatAttr>()) 6439 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6440 "printf", FormatIdx+1, 6441 HasVAListArg ? 0 : FormatIdx+2)); 6442 } 6443 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 6444 HasVAListArg)) { 6445 if (!FD->getAttr<FormatAttr>()) 6446 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6447 "scanf", FormatIdx+1, 6448 HasVAListArg ? 0 : FormatIdx+2)); 6449 } 6450 6451 // Mark const if we don't care about errno and that is the only 6452 // thing preventing the function from being const. This allows 6453 // IRgen to use LLVM intrinsics for such functions. 6454 if (!getLangOptions().MathErrno && 6455 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 6456 if (!FD->getAttr<ConstAttr>()) 6457 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6458 } 6459 6460 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 6461 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 6462 if (Context.BuiltinInfo.isConst(BuiltinID)) 6463 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6464 } 6465 6466 IdentifierInfo *Name = FD->getIdentifier(); 6467 if (!Name) 6468 return; 6469 if ((!getLangOptions().CPlusPlus && 6470 FD->getDeclContext()->isTranslationUnit()) || 6471 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 6472 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 6473 LinkageSpecDecl::lang_c)) { 6474 // Okay: this could be a libc/libm/Objective-C function we know 6475 // about. 6476 } else 6477 return; 6478 6479 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 6480 // FIXME: NSLog and NSLogv should be target specific 6481 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 6482 // FIXME: We known better than our headers. 6483 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 6484 } else 6485 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6486 "printf", 1, 6487 Name->isStr("NSLogv") ? 0 : 2)); 6488 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 6489 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 6490 // target-specific builtins, perhaps? 6491 if (!FD->getAttr<FormatAttr>()) 6492 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6493 "printf", 2, 6494 Name->isStr("vasprintf") ? 0 : 3)); 6495 } 6496} 6497 6498TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 6499 TypeSourceInfo *TInfo) { 6500 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 6501 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 6502 6503 if (!TInfo) { 6504 assert(D.isInvalidType() && "no declarator info for valid type"); 6505 TInfo = Context.getTrivialTypeSourceInfo(T); 6506 } 6507 6508 // Scope manipulation handled by caller. 6509 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 6510 D.getSourceRange().getBegin(), 6511 D.getIdentifierLoc(), 6512 D.getIdentifier(), 6513 TInfo); 6514 6515 // Bail out immediately if we have an invalid declaration. 6516 if (D.isInvalidType()) { 6517 NewTD->setInvalidDecl(); 6518 return NewTD; 6519 } 6520 6521 // C++ [dcl.typedef]p8: 6522 // If the typedef declaration defines an unnamed class (or 6523 // enum), the first typedef-name declared by the declaration 6524 // to be that class type (or enum type) is used to denote the 6525 // class type (or enum type) for linkage purposes only. 6526 // We need to check whether the type was declared in the declaration. 6527 switch (D.getDeclSpec().getTypeSpecType()) { 6528 case TST_enum: 6529 case TST_struct: 6530 case TST_union: 6531 case TST_class: { 6532 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); 6533 6534 // Do nothing if the tag is not anonymous or already has an 6535 // associated typedef (from an earlier typedef in this decl group). 6536 if (tagFromDeclSpec->getIdentifier()) break; 6537 if (tagFromDeclSpec->getTypedefNameForAnonDecl()) break; 6538 6539 // A well-formed anonymous tag must always be a TUK_Definition. 6540 assert(tagFromDeclSpec->isThisDeclarationADefinition()); 6541 6542 // The type must match the tag exactly; no qualifiers allowed. 6543 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) 6544 break; 6545 6546 // Otherwise, set this is the anon-decl typedef for the tag. 6547 tagFromDeclSpec->setTypedefNameForAnonDecl(NewTD); 6548 break; 6549 } 6550 6551 default: 6552 break; 6553 } 6554 6555 return NewTD; 6556} 6557 6558 6559/// \brief Determine whether a tag with a given kind is acceptable 6560/// as a redeclaration of the given tag declaration. 6561/// 6562/// \returns true if the new tag kind is acceptable, false otherwise. 6563bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 6564 TagTypeKind NewTag, 6565 SourceLocation NewTagLoc, 6566 const IdentifierInfo &Name) { 6567 // C++ [dcl.type.elab]p3: 6568 // The class-key or enum keyword present in the 6569 // elaborated-type-specifier shall agree in kind with the 6570 // declaration to which the name in the elaborated-type-specifier 6571 // refers. This rule also applies to the form of 6572 // elaborated-type-specifier that declares a class-name or 6573 // friend class since it can be construed as referring to the 6574 // definition of the class. Thus, in any 6575 // elaborated-type-specifier, the enum keyword shall be used to 6576 // refer to an enumeration (7.2), the union class-key shall be 6577 // used to refer to a union (clause 9), and either the class or 6578 // struct class-key shall be used to refer to a class (clause 9) 6579 // declared using the class or struct class-key. 6580 TagTypeKind OldTag = Previous->getTagKind(); 6581 if (OldTag == NewTag) 6582 return true; 6583 6584 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 6585 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 6586 // Warn about the struct/class tag mismatch. 6587 bool isTemplate = false; 6588 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 6589 isTemplate = Record->getDescribedClassTemplate(); 6590 6591 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 6592 << (NewTag == TTK_Class) 6593 << isTemplate << &Name 6594 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 6595 OldTag == TTK_Class? "class" : "struct"); 6596 Diag(Previous->getLocation(), diag::note_previous_use); 6597 return true; 6598 } 6599 return false; 6600} 6601 6602/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 6603/// former case, Name will be non-null. In the later case, Name will be null. 6604/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 6605/// reference/declaration/definition of a tag. 6606Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 6607 SourceLocation KWLoc, CXXScopeSpec &SS, 6608 IdentifierInfo *Name, SourceLocation NameLoc, 6609 AttributeList *Attr, AccessSpecifier AS, 6610 MultiTemplateParamsArg TemplateParameterLists, 6611 bool &OwnedDecl, bool &IsDependent, 6612 bool ScopedEnum, bool ScopedEnumUsesClassTag, 6613 TypeResult UnderlyingType) { 6614 // If this is not a definition, it must have a name. 6615 assert((Name != 0 || TUK == TUK_Definition) && 6616 "Nameless record must be a definition!"); 6617 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 6618 6619 OwnedDecl = false; 6620 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 6621 6622 // FIXME: Check explicit specializations more carefully. 6623 bool isExplicitSpecialization = false; 6624 bool Invalid = false; 6625 6626 // We only need to do this matching if we have template parameters 6627 // or a scope specifier, which also conveniently avoids this work 6628 // for non-C++ cases. 6629 if (TemplateParameterLists.size() > 0 || 6630 (SS.isNotEmpty() && TUK != TUK_Reference)) { 6631 if (TemplateParameterList *TemplateParams 6632 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 6633 TemplateParameterLists.get(), 6634 TemplateParameterLists.size(), 6635 TUK == TUK_Friend, 6636 isExplicitSpecialization, 6637 Invalid)) { 6638 if (TemplateParams->size() > 0) { 6639 // This is a declaration or definition of a class template (which may 6640 // be a member of another template). 6641 6642 if (Invalid) 6643 return 0; 6644 6645 OwnedDecl = false; 6646 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 6647 SS, Name, NameLoc, Attr, 6648 TemplateParams, AS, 6649 TemplateParameterLists.size() - 1, 6650 (TemplateParameterList**) TemplateParameterLists.release()); 6651 return Result.get(); 6652 } else { 6653 // The "template<>" header is extraneous. 6654 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 6655 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 6656 isExplicitSpecialization = true; 6657 } 6658 } 6659 } 6660 6661 // Figure out the underlying type if this a enum declaration. We need to do 6662 // this early, because it's needed to detect if this is an incompatible 6663 // redeclaration. 6664 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 6665 6666 if (Kind == TTK_Enum) { 6667 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 6668 // No underlying type explicitly specified, or we failed to parse the 6669 // type, default to int. 6670 EnumUnderlying = Context.IntTy.getTypePtr(); 6671 else if (UnderlyingType.get()) { 6672 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 6673 // integral type; any cv-qualification is ignored. 6674 TypeSourceInfo *TI = 0; 6675 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 6676 EnumUnderlying = TI; 6677 6678 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 6679 6680 if (!T->isDependentType() && !T->isIntegralType(Context)) { 6681 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 6682 << T; 6683 // Recover by falling back to int. 6684 EnumUnderlying = Context.IntTy.getTypePtr(); 6685 } 6686 6687 if (DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI, 6688 UPPC_FixedUnderlyingType)) 6689 EnumUnderlying = Context.IntTy.getTypePtr(); 6690 6691 } else if (getLangOptions().Microsoft) 6692 // Microsoft enums are always of int type. 6693 EnumUnderlying = Context.IntTy.getTypePtr(); 6694 } 6695 6696 DeclContext *SearchDC = CurContext; 6697 DeclContext *DC = CurContext; 6698 bool isStdBadAlloc = false; 6699 6700 RedeclarationKind Redecl = ForRedeclaration; 6701 if (TUK == TUK_Friend || TUK == TUK_Reference) 6702 Redecl = NotForRedeclaration; 6703 6704 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 6705 6706 if (Name && SS.isNotEmpty()) { 6707 // We have a nested-name tag ('struct foo::bar'). 6708 6709 // Check for invalid 'foo::'. 6710 if (SS.isInvalid()) { 6711 Name = 0; 6712 goto CreateNewDecl; 6713 } 6714 6715 // If this is a friend or a reference to a class in a dependent 6716 // context, don't try to make a decl for it. 6717 if (TUK == TUK_Friend || TUK == TUK_Reference) { 6718 DC = computeDeclContext(SS, false); 6719 if (!DC) { 6720 IsDependent = true; 6721 return 0; 6722 } 6723 } else { 6724 DC = computeDeclContext(SS, true); 6725 if (!DC) { 6726 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 6727 << SS.getRange(); 6728 return 0; 6729 } 6730 } 6731 6732 if (RequireCompleteDeclContext(SS, DC)) 6733 return 0; 6734 6735 SearchDC = DC; 6736 // Look-up name inside 'foo::'. 6737 LookupQualifiedName(Previous, DC); 6738 6739 if (Previous.isAmbiguous()) 6740 return 0; 6741 6742 if (Previous.empty()) { 6743 // Name lookup did not find anything. However, if the 6744 // nested-name-specifier refers to the current instantiation, 6745 // and that current instantiation has any dependent base 6746 // classes, we might find something at instantiation time: treat 6747 // this as a dependent elaborated-type-specifier. 6748 // But this only makes any sense for reference-like lookups. 6749 if (Previous.wasNotFoundInCurrentInstantiation() && 6750 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6751 IsDependent = true; 6752 return 0; 6753 } 6754 6755 // A tag 'foo::bar' must already exist. 6756 Diag(NameLoc, diag::err_not_tag_in_scope) 6757 << Kind << Name << DC << SS.getRange(); 6758 Name = 0; 6759 Invalid = true; 6760 goto CreateNewDecl; 6761 } 6762 } else if (Name) { 6763 // If this is a named struct, check to see if there was a previous forward 6764 // declaration or definition. 6765 // FIXME: We're looking into outer scopes here, even when we 6766 // shouldn't be. Doing so can result in ambiguities that we 6767 // shouldn't be diagnosing. 6768 LookupName(Previous, S); 6769 6770 if (Previous.isAmbiguous() && TUK == TUK_Definition) { 6771 LookupResult::Filter F = Previous.makeFilter(); 6772 while (F.hasNext()) { 6773 NamedDecl *ND = F.next(); 6774 if (ND->getDeclContext()->getRedeclContext() != SearchDC) 6775 F.erase(); 6776 } 6777 F.done(); 6778 6779 if (Previous.isAmbiguous()) 6780 return 0; 6781 } 6782 6783 // Note: there used to be some attempt at recovery here. 6784 if (Previous.isAmbiguous()) 6785 return 0; 6786 6787 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 6788 // FIXME: This makes sure that we ignore the contexts associated 6789 // with C structs, unions, and enums when looking for a matching 6790 // tag declaration or definition. See the similar lookup tweak 6791 // in Sema::LookupName; is there a better way to deal with this? 6792 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 6793 SearchDC = SearchDC->getParent(); 6794 } 6795 } else if (S->isFunctionPrototypeScope()) { 6796 // If this is an enum declaration in function prototype scope, set its 6797 // initial context to the translation unit. 6798 SearchDC = Context.getTranslationUnitDecl(); 6799 } 6800 6801 if (Previous.isSingleResult() && 6802 Previous.getFoundDecl()->isTemplateParameter()) { 6803 // Maybe we will complain about the shadowed template parameter. 6804 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 6805 // Just pretend that we didn't see the previous declaration. 6806 Previous.clear(); 6807 } 6808 6809 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 6810 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 6811 // This is a declaration of or a reference to "std::bad_alloc". 6812 isStdBadAlloc = true; 6813 6814 if (Previous.empty() && StdBadAlloc) { 6815 // std::bad_alloc has been implicitly declared (but made invisible to 6816 // name lookup). Fill in this implicit declaration as the previous 6817 // declaration, so that the declarations get chained appropriately. 6818 Previous.addDecl(getStdBadAlloc()); 6819 } 6820 } 6821 6822 // If we didn't find a previous declaration, and this is a reference 6823 // (or friend reference), move to the correct scope. In C++, we 6824 // also need to do a redeclaration lookup there, just in case 6825 // there's a shadow friend decl. 6826 if (Name && Previous.empty() && 6827 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6828 if (Invalid) goto CreateNewDecl; 6829 assert(SS.isEmpty()); 6830 6831 if (TUK == TUK_Reference) { 6832 // C++ [basic.scope.pdecl]p5: 6833 // -- for an elaborated-type-specifier of the form 6834 // 6835 // class-key identifier 6836 // 6837 // if the elaborated-type-specifier is used in the 6838 // decl-specifier-seq or parameter-declaration-clause of a 6839 // function defined in namespace scope, the identifier is 6840 // declared as a class-name in the namespace that contains 6841 // the declaration; otherwise, except as a friend 6842 // declaration, the identifier is declared in the smallest 6843 // non-class, non-function-prototype scope that contains the 6844 // declaration. 6845 // 6846 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 6847 // C structs and unions. 6848 // 6849 // It is an error in C++ to declare (rather than define) an enum 6850 // type, including via an elaborated type specifier. We'll 6851 // diagnose that later; for now, declare the enum in the same 6852 // scope as we would have picked for any other tag type. 6853 // 6854 // GNU C also supports this behavior as part of its incomplete 6855 // enum types extension, while GNU C++ does not. 6856 // 6857 // Find the context where we'll be declaring the tag. 6858 // FIXME: We would like to maintain the current DeclContext as the 6859 // lexical context, 6860 while (SearchDC->isRecord() || SearchDC->isTransparentContext()) 6861 SearchDC = SearchDC->getParent(); 6862 6863 // Find the scope where we'll be declaring the tag. 6864 while (S->isClassScope() || 6865 (getLangOptions().CPlusPlus && 6866 S->isFunctionPrototypeScope()) || 6867 ((S->getFlags() & Scope::DeclScope) == 0) || 6868 (S->getEntity() && 6869 ((DeclContext *)S->getEntity())->isTransparentContext())) 6870 S = S->getParent(); 6871 } else { 6872 assert(TUK == TUK_Friend); 6873 // C++ [namespace.memdef]p3: 6874 // If a friend declaration in a non-local class first declares a 6875 // class or function, the friend class or function is a member of 6876 // the innermost enclosing namespace. 6877 SearchDC = SearchDC->getEnclosingNamespaceContext(); 6878 } 6879 6880 // In C++, we need to do a redeclaration lookup to properly 6881 // diagnose some problems. 6882 if (getLangOptions().CPlusPlus) { 6883 Previous.setRedeclarationKind(ForRedeclaration); 6884 LookupQualifiedName(Previous, SearchDC); 6885 } 6886 } 6887 6888 if (!Previous.empty()) { 6889 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 6890 6891 // It's okay to have a tag decl in the same scope as a typedef 6892 // which hides a tag decl in the same scope. Finding this 6893 // insanity with a redeclaration lookup can only actually happen 6894 // in C++. 6895 // 6896 // This is also okay for elaborated-type-specifiers, which is 6897 // technically forbidden by the current standard but which is 6898 // okay according to the likely resolution of an open issue; 6899 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 6900 if (getLangOptions().CPlusPlus) { 6901 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) { 6902 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 6903 TagDecl *Tag = TT->getDecl(); 6904 if (Tag->getDeclName() == Name && 6905 Tag->getDeclContext()->getRedeclContext() 6906 ->Equals(TD->getDeclContext()->getRedeclContext())) { 6907 PrevDecl = Tag; 6908 Previous.clear(); 6909 Previous.addDecl(Tag); 6910 Previous.resolveKind(); 6911 } 6912 } 6913 } 6914 } 6915 6916 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 6917 // If this is a use of a previous tag, or if the tag is already declared 6918 // in the same scope (so that the definition/declaration completes or 6919 // rementions the tag), reuse the decl. 6920 if (TUK == TUK_Reference || TUK == TUK_Friend || 6921 isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { 6922 // Make sure that this wasn't declared as an enum and now used as a 6923 // struct or something similar. 6924 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 6925 bool SafeToContinue 6926 = (PrevTagDecl->getTagKind() != TTK_Enum && 6927 Kind != TTK_Enum); 6928 if (SafeToContinue) 6929 Diag(KWLoc, diag::err_use_with_wrong_tag) 6930 << Name 6931 << FixItHint::CreateReplacement(SourceRange(KWLoc), 6932 PrevTagDecl->getKindName()); 6933 else 6934 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 6935 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6936 6937 if (SafeToContinue) 6938 Kind = PrevTagDecl->getTagKind(); 6939 else { 6940 // Recover by making this an anonymous redefinition. 6941 Name = 0; 6942 Previous.clear(); 6943 Invalid = true; 6944 } 6945 } 6946 6947 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 6948 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 6949 6950 // All conflicts with previous declarations are recovered by 6951 // returning the previous declaration. 6952 if (ScopedEnum != PrevEnum->isScoped()) { 6953 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 6954 << PrevEnum->isScoped(); 6955 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6956 return PrevTagDecl; 6957 } 6958 else if (EnumUnderlying && PrevEnum->isFixed()) { 6959 QualType T; 6960 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6961 T = TI->getType(); 6962 else 6963 T = QualType(EnumUnderlying.get<const Type*>(), 0); 6964 6965 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 6966 Diag(NameLoc.isValid() ? NameLoc : KWLoc, 6967 diag::err_enum_redeclare_type_mismatch) 6968 << T 6969 << PrevEnum->getIntegerType(); 6970 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6971 return PrevTagDecl; 6972 } 6973 } 6974 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 6975 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 6976 << PrevEnum->isFixed(); 6977 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6978 return PrevTagDecl; 6979 } 6980 } 6981 6982 if (!Invalid) { 6983 // If this is a use, just return the declaration we found. 6984 6985 // FIXME: In the future, return a variant or some other clue 6986 // for the consumer of this Decl to know it doesn't own it. 6987 // For our current ASTs this shouldn't be a problem, but will 6988 // need to be changed with DeclGroups. 6989 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 6990 TUK == TUK_Friend) 6991 return PrevTagDecl; 6992 6993 // Diagnose attempts to redefine a tag. 6994 if (TUK == TUK_Definition) { 6995 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 6996 // If we're defining a specialization and the previous definition 6997 // is from an implicit instantiation, don't emit an error 6998 // here; we'll catch this in the general case below. 6999 if (!isExplicitSpecialization || 7000 !isa<CXXRecordDecl>(Def) || 7001 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 7002 == TSK_ExplicitSpecialization) { 7003 Diag(NameLoc, diag::err_redefinition) << Name; 7004 Diag(Def->getLocation(), diag::note_previous_definition); 7005 // If this is a redefinition, recover by making this 7006 // struct be anonymous, which will make any later 7007 // references get the previous definition. 7008 Name = 0; 7009 Previous.clear(); 7010 Invalid = true; 7011 } 7012 } else { 7013 // If the type is currently being defined, complain 7014 // about a nested redefinition. 7015 const TagType *Tag 7016 = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 7017 if (Tag->isBeingDefined()) { 7018 Diag(NameLoc, diag::err_nested_redefinition) << Name; 7019 Diag(PrevTagDecl->getLocation(), 7020 diag::note_previous_definition); 7021 Name = 0; 7022 Previous.clear(); 7023 Invalid = true; 7024 } 7025 } 7026 7027 // Okay, this is definition of a previously declared or referenced 7028 // tag PrevDecl. We're going to create a new Decl for it. 7029 } 7030 } 7031 // If we get here we have (another) forward declaration or we 7032 // have a definition. Just create a new decl. 7033 7034 } else { 7035 // If we get here, this is a definition of a new tag type in a nested 7036 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 7037 // new decl/type. We set PrevDecl to NULL so that the entities 7038 // have distinct types. 7039 Previous.clear(); 7040 } 7041 // If we get here, we're going to create a new Decl. If PrevDecl 7042 // is non-NULL, it's a definition of the tag declared by 7043 // PrevDecl. If it's NULL, we have a new definition. 7044 7045 7046 // Otherwise, PrevDecl is not a tag, but was found with tag 7047 // lookup. This is only actually possible in C++, where a few 7048 // things like templates still live in the tag namespace. 7049 } else { 7050 assert(getLangOptions().CPlusPlus); 7051 7052 // Use a better diagnostic if an elaborated-type-specifier 7053 // found the wrong kind of type on the first 7054 // (non-redeclaration) lookup. 7055 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 7056 !Previous.isForRedeclaration()) { 7057 unsigned Kind = 0; 7058 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 7059 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; 7060 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; 7061 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 7062 Diag(PrevDecl->getLocation(), diag::note_declared_at); 7063 Invalid = true; 7064 7065 // Otherwise, only diagnose if the declaration is in scope. 7066 } else if (!isDeclInScope(PrevDecl, SearchDC, S, 7067 isExplicitSpecialization)) { 7068 // do nothing 7069 7070 // Diagnose implicit declarations introduced by elaborated types. 7071 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 7072 unsigned Kind = 0; 7073 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 7074 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; 7075 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; 7076 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 7077 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 7078 Invalid = true; 7079 7080 // Otherwise it's a declaration. Call out a particularly common 7081 // case here. 7082 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) { 7083 unsigned Kind = 0; 7084 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1; 7085 Diag(NameLoc, diag::err_tag_definition_of_typedef) 7086 << Name << Kind << TND->getUnderlyingType(); 7087 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 7088 Invalid = true; 7089 7090 // Otherwise, diagnose. 7091 } else { 7092 // The tag name clashes with something else in the target scope, 7093 // issue an error and recover by making this tag be anonymous. 7094 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 7095 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7096 Name = 0; 7097 Invalid = true; 7098 } 7099 7100 // The existing declaration isn't relevant to us; we're in a 7101 // new scope, so clear out the previous declaration. 7102 Previous.clear(); 7103 } 7104 } 7105 7106CreateNewDecl: 7107 7108 TagDecl *PrevDecl = 0; 7109 if (Previous.isSingleResult()) 7110 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 7111 7112 // If there is an identifier, use the location of the identifier as the 7113 // location of the decl, otherwise use the location of the struct/union 7114 // keyword. 7115 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 7116 7117 // Otherwise, create a new declaration. If there is a previous 7118 // declaration of the same entity, the two will be linked via 7119 // PrevDecl. 7120 TagDecl *New; 7121 7122 bool IsForwardReference = false; 7123 if (Kind == TTK_Enum) { 7124 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 7125 // enum X { A, B, C } D; D should chain to X. 7126 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, 7127 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 7128 ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); 7129 // If this is an undefined enum, warn. 7130 if (TUK != TUK_Definition && !Invalid) { 7131 TagDecl *Def; 7132 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 7133 // C++0x: 7.2p2: opaque-enum-declaration. 7134 // Conflicts are diagnosed above. Do nothing. 7135 } 7136 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 7137 Diag(Loc, diag::ext_forward_ref_enum_def) 7138 << New; 7139 Diag(Def->getLocation(), diag::note_previous_definition); 7140 } else { 7141 unsigned DiagID = diag::ext_forward_ref_enum; 7142 if (getLangOptions().Microsoft) 7143 DiagID = diag::ext_ms_forward_ref_enum; 7144 else if (getLangOptions().CPlusPlus) 7145 DiagID = diag::err_forward_ref_enum; 7146 Diag(Loc, DiagID); 7147 7148 // If this is a forward-declared reference to an enumeration, make a 7149 // note of it; we won't actually be introducing the declaration into 7150 // the declaration context. 7151 if (TUK == TUK_Reference) 7152 IsForwardReference = true; 7153 } 7154 } 7155 7156 if (EnumUnderlying) { 7157 EnumDecl *ED = cast<EnumDecl>(New); 7158 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 7159 ED->setIntegerTypeSourceInfo(TI); 7160 else 7161 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 7162 ED->setPromotionType(ED->getIntegerType()); 7163 } 7164 7165 } else { 7166 // struct/union/class 7167 7168 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 7169 // struct X { int A; } D; D should chain to X. 7170 if (getLangOptions().CPlusPlus) { 7171 // FIXME: Look for a way to use RecordDecl for simple structs. 7172 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 7173 cast_or_null<CXXRecordDecl>(PrevDecl)); 7174 7175 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 7176 StdBadAlloc = cast<CXXRecordDecl>(New); 7177 } else 7178 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 7179 cast_or_null<RecordDecl>(PrevDecl)); 7180 } 7181 7182 // Maybe add qualifier info. 7183 if (SS.isNotEmpty()) { 7184 if (SS.isSet()) { 7185 New->setQualifierInfo(SS.getWithLocInContext(Context)); 7186 if (TemplateParameterLists.size() > 0) { 7187 New->setTemplateParameterListsInfo(Context, 7188 TemplateParameterLists.size(), 7189 (TemplateParameterList**) TemplateParameterLists.release()); 7190 } 7191 } 7192 else 7193 Invalid = true; 7194 } 7195 7196 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 7197 // Add alignment attributes if necessary; these attributes are checked when 7198 // the ASTContext lays out the structure. 7199 // 7200 // It is important for implementing the correct semantics that this 7201 // happen here (in act on tag decl). The #pragma pack stack is 7202 // maintained as a result of parser callbacks which can occur at 7203 // many points during the parsing of a struct declaration (because 7204 // the #pragma tokens are effectively skipped over during the 7205 // parsing of the struct). 7206 AddAlignmentAttributesForRecord(RD); 7207 7208 AddMsStructLayoutForRecord(RD); 7209 } 7210 7211 // If this is a specialization of a member class (of a class template), 7212 // check the specialization. 7213 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 7214 Invalid = true; 7215 7216 if (Invalid) 7217 New->setInvalidDecl(); 7218 7219 if (Attr) 7220 ProcessDeclAttributeList(S, New, Attr); 7221 7222 // If we're declaring or defining a tag in function prototype scope 7223 // in C, note that this type can only be used within the function. 7224 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 7225 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 7226 7227 // Set the lexical context. If the tag has a C++ scope specifier, the 7228 // lexical context will be different from the semantic context. 7229 New->setLexicalDeclContext(CurContext); 7230 7231 // Mark this as a friend decl if applicable. 7232 if (TUK == TUK_Friend) 7233 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 7234 7235 // Set the access specifier. 7236 if (!Invalid && SearchDC->isRecord()) 7237 SetMemberAccessSpecifier(New, PrevDecl, AS); 7238 7239 if (TUK == TUK_Definition) 7240 New->startDefinition(); 7241 7242 // If this has an identifier, add it to the scope stack. 7243 if (TUK == TUK_Friend) { 7244 // We might be replacing an existing declaration in the lookup tables; 7245 // if so, borrow its access specifier. 7246 if (PrevDecl) 7247 New->setAccess(PrevDecl->getAccess()); 7248 7249 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 7250 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 7251 if (Name) // can be null along some error paths 7252 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 7253 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 7254 } else if (Name) { 7255 S = getNonFieldDeclScope(S); 7256 PushOnScopeChains(New, S, !IsForwardReference); 7257 if (IsForwardReference) 7258 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 7259 7260 } else { 7261 CurContext->addDecl(New); 7262 } 7263 7264 // If this is the C FILE type, notify the AST context. 7265 if (IdentifierInfo *II = New->getIdentifier()) 7266 if (!New->isInvalidDecl() && 7267 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 7268 II->isStr("FILE")) 7269 Context.setFILEDecl(New); 7270 7271 OwnedDecl = true; 7272 return New; 7273} 7274 7275void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 7276 AdjustDeclIfTemplate(TagD); 7277 TagDecl *Tag = cast<TagDecl>(TagD); 7278 7279 // Enter the tag context. 7280 PushDeclContext(S, Tag); 7281} 7282 7283void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 7284 SourceLocation FinalLoc, 7285 SourceLocation LBraceLoc) { 7286 AdjustDeclIfTemplate(TagD); 7287 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 7288 7289 FieldCollector->StartClass(); 7290 7291 if (!Record->getIdentifier()) 7292 return; 7293 7294 if (FinalLoc.isValid()) 7295 Record->addAttr(new (Context) FinalAttr(FinalLoc, Context)); 7296 7297 // C++ [class]p2: 7298 // [...] The class-name is also inserted into the scope of the 7299 // class itself; this is known as the injected-class-name. For 7300 // purposes of access checking, the injected-class-name is treated 7301 // as if it were a public member name. 7302 CXXRecordDecl *InjectedClassName 7303 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext, 7304 Record->getLocStart(), Record->getLocation(), 7305 Record->getIdentifier(), 7306 /*PrevDecl=*/0, 7307 /*DelayTypeCreation=*/true); 7308 Context.getTypeDeclType(InjectedClassName, Record); 7309 InjectedClassName->setImplicit(); 7310 InjectedClassName->setAccess(AS_public); 7311 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 7312 InjectedClassName->setDescribedClassTemplate(Template); 7313 PushOnScopeChains(InjectedClassName, S); 7314 assert(InjectedClassName->isInjectedClassName() && 7315 "Broken injected-class-name"); 7316} 7317 7318void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 7319 SourceLocation RBraceLoc) { 7320 AdjustDeclIfTemplate(TagD); 7321 TagDecl *Tag = cast<TagDecl>(TagD); 7322 Tag->setRBraceLoc(RBraceLoc); 7323 7324 if (isa<CXXRecordDecl>(Tag)) 7325 FieldCollector->FinishClass(); 7326 7327 // Exit this scope of this tag's definition. 7328 PopDeclContext(); 7329 7330 // Notify the consumer that we've defined a tag. 7331 Consumer.HandleTagDeclDefinition(Tag); 7332} 7333 7334void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 7335 AdjustDeclIfTemplate(TagD); 7336 TagDecl *Tag = cast<TagDecl>(TagD); 7337 Tag->setInvalidDecl(); 7338 7339 // We're undoing ActOnTagStartDefinition here, not 7340 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 7341 // the FieldCollector. 7342 7343 PopDeclContext(); 7344} 7345 7346// Note that FieldName may be null for anonymous bitfields. 7347bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 7348 QualType FieldTy, const Expr *BitWidth, 7349 bool *ZeroWidth) { 7350 // Default to true; that shouldn't confuse checks for emptiness 7351 if (ZeroWidth) 7352 *ZeroWidth = true; 7353 7354 // C99 6.7.2.1p4 - verify the field type. 7355 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 7356 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 7357 // Handle incomplete types with specific error. 7358 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 7359 return true; 7360 if (FieldName) 7361 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 7362 << FieldName << FieldTy << BitWidth->getSourceRange(); 7363 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 7364 << FieldTy << BitWidth->getSourceRange(); 7365 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), 7366 UPPC_BitFieldWidth)) 7367 return true; 7368 7369 // If the bit-width is type- or value-dependent, don't try to check 7370 // it now. 7371 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 7372 return false; 7373 7374 llvm::APSInt Value; 7375 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 7376 return true; 7377 7378 if (Value != 0 && ZeroWidth) 7379 *ZeroWidth = false; 7380 7381 // Zero-width bitfield is ok for anonymous field. 7382 if (Value == 0 && FieldName) 7383 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 7384 7385 if (Value.isSigned() && Value.isNegative()) { 7386 if (FieldName) 7387 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 7388 << FieldName << Value.toString(10); 7389 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 7390 << Value.toString(10); 7391 } 7392 7393 if (!FieldTy->isDependentType()) { 7394 uint64_t TypeSize = Context.getTypeSize(FieldTy); 7395 if (Value.getZExtValue() > TypeSize) { 7396 if (!getLangOptions().CPlusPlus) { 7397 if (FieldName) 7398 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 7399 << FieldName << (unsigned)Value.getZExtValue() 7400 << (unsigned)TypeSize; 7401 7402 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 7403 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 7404 } 7405 7406 if (FieldName) 7407 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 7408 << FieldName << (unsigned)Value.getZExtValue() 7409 << (unsigned)TypeSize; 7410 else 7411 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 7412 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 7413 } 7414 } 7415 7416 return false; 7417} 7418 7419/// ActOnField - Each field of a struct/union/class is passed into this in order 7420/// to create a FieldDecl object for it. 7421Decl *Sema::ActOnField(Scope *S, Decl *TagD, 7422 SourceLocation DeclStart, 7423 Declarator &D, ExprTy *BitfieldWidth) { 7424 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 7425 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 7426 AS_public); 7427 return Res; 7428} 7429 7430/// HandleField - Analyze a field of a C struct or a C++ data member. 7431/// 7432FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 7433 SourceLocation DeclStart, 7434 Declarator &D, Expr *BitWidth, 7435 AccessSpecifier AS) { 7436 IdentifierInfo *II = D.getIdentifier(); 7437 SourceLocation Loc = DeclStart; 7438 if (II) Loc = D.getIdentifierLoc(); 7439 7440 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7441 QualType T = TInfo->getType(); 7442 if (getLangOptions().CPlusPlus) { 7443 CheckExtraCXXDefaultArguments(D); 7444 7445 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 7446 UPPC_DataMemberType)) { 7447 D.setInvalidType(); 7448 T = Context.IntTy; 7449 TInfo = Context.getTrivialTypeSourceInfo(T, Loc); 7450 } 7451 } 7452 7453 DiagnoseFunctionSpecifiers(D); 7454 7455 if (D.getDeclSpec().isThreadSpecified()) 7456 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 7457 7458 // Check to see if this name was declared as a member previously 7459 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 7460 LookupName(Previous, S); 7461 assert((Previous.empty() || Previous.isOverloadedResult() || 7462 Previous.isSingleResult()) 7463 && "Lookup of member name should be either overloaded, single or null"); 7464 7465 // If the name is overloaded then get any declaration else get the single result 7466 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 7467 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 7468 7469 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7470 // Maybe we will complain about the shadowed template parameter. 7471 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 7472 // Just pretend that we didn't see the previous declaration. 7473 PrevDecl = 0; 7474 } 7475 7476 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 7477 PrevDecl = 0; 7478 7479 bool Mutable 7480 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 7481 SourceLocation TSSL = D.getSourceRange().getBegin(); 7482 FieldDecl *NewFD 7483 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 7484 AS, PrevDecl, &D); 7485 7486 if (NewFD->isInvalidDecl()) 7487 Record->setInvalidDecl(); 7488 7489 if (NewFD->isInvalidDecl() && PrevDecl) { 7490 // Don't introduce NewFD into scope; there's already something 7491 // with the same name in the same scope. 7492 } else if (II) { 7493 PushOnScopeChains(NewFD, S); 7494 } else 7495 Record->addDecl(NewFD); 7496 7497 return NewFD; 7498} 7499 7500/// \brief Build a new FieldDecl and check its well-formedness. 7501/// 7502/// This routine builds a new FieldDecl given the fields name, type, 7503/// record, etc. \p PrevDecl should refer to any previous declaration 7504/// with the same name and in the same scope as the field to be 7505/// created. 7506/// 7507/// \returns a new FieldDecl. 7508/// 7509/// \todo The Declarator argument is a hack. It will be removed once 7510FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 7511 TypeSourceInfo *TInfo, 7512 RecordDecl *Record, SourceLocation Loc, 7513 bool Mutable, Expr *BitWidth, 7514 SourceLocation TSSL, 7515 AccessSpecifier AS, NamedDecl *PrevDecl, 7516 Declarator *D) { 7517 IdentifierInfo *II = Name.getAsIdentifierInfo(); 7518 bool InvalidDecl = false; 7519 if (D) InvalidDecl = D->isInvalidType(); 7520 7521 // If we receive a broken type, recover by assuming 'int' and 7522 // marking this declaration as invalid. 7523 if (T.isNull()) { 7524 InvalidDecl = true; 7525 T = Context.IntTy; 7526 } 7527 7528 QualType EltTy = Context.getBaseElementType(T); 7529 if (!EltTy->isDependentType() && 7530 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 7531 // Fields of incomplete type force their record to be invalid. 7532 Record->setInvalidDecl(); 7533 InvalidDecl = true; 7534 } 7535 7536 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7537 // than a variably modified type. 7538 if (!InvalidDecl && T->isVariablyModifiedType()) { 7539 bool SizeIsNegative; 7540 llvm::APSInt Oversized; 7541 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 7542 SizeIsNegative, 7543 Oversized); 7544 if (!FixedTy.isNull()) { 7545 Diag(Loc, diag::warn_illegal_constant_array_size); 7546 T = FixedTy; 7547 } else { 7548 if (SizeIsNegative) 7549 Diag(Loc, diag::err_typecheck_negative_array_size); 7550 else if (Oversized.getBoolValue()) 7551 Diag(Loc, diag::err_array_too_large) 7552 << Oversized.toString(10); 7553 else 7554 Diag(Loc, diag::err_typecheck_field_variable_size); 7555 InvalidDecl = true; 7556 } 7557 } 7558 7559 // Fields can not have abstract class types 7560 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 7561 diag::err_abstract_type_in_decl, 7562 AbstractFieldType)) 7563 InvalidDecl = true; 7564 7565 bool ZeroWidth = false; 7566 // If this is declared as a bit-field, check the bit-field. 7567 if (!InvalidDecl && BitWidth && 7568 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 7569 InvalidDecl = true; 7570 BitWidth = 0; 7571 ZeroWidth = false; 7572 } 7573 7574 // Check that 'mutable' is consistent with the type of the declaration. 7575 if (!InvalidDecl && Mutable) { 7576 unsigned DiagID = 0; 7577 if (T->isReferenceType()) 7578 DiagID = diag::err_mutable_reference; 7579 else if (T.isConstQualified()) 7580 DiagID = diag::err_mutable_const; 7581 7582 if (DiagID) { 7583 SourceLocation ErrLoc = Loc; 7584 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 7585 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 7586 Diag(ErrLoc, DiagID); 7587 Mutable = false; 7588 InvalidDecl = true; 7589 } 7590 } 7591 7592 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo, 7593 BitWidth, Mutable); 7594 if (InvalidDecl) 7595 NewFD->setInvalidDecl(); 7596 7597 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 7598 Diag(Loc, diag::err_duplicate_member) << II; 7599 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7600 NewFD->setInvalidDecl(); 7601 } 7602 7603 if (!InvalidDecl && getLangOptions().CPlusPlus) { 7604 if (Record->isUnion()) { 7605 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7606 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7607 if (RDecl->getDefinition()) { 7608 // C++ [class.union]p1: An object of a class with a non-trivial 7609 // constructor, a non-trivial copy constructor, a non-trivial 7610 // destructor, or a non-trivial copy assignment operator 7611 // cannot be a member of a union, nor can an array of such 7612 // objects. 7613 // TODO: C++0x alters this restriction significantly. 7614 if (CheckNontrivialField(NewFD)) 7615 NewFD->setInvalidDecl(); 7616 } 7617 } 7618 7619 // C++ [class.union]p1: If a union contains a member of reference type, 7620 // the program is ill-formed. 7621 if (EltTy->isReferenceType()) { 7622 Diag(NewFD->getLocation(), diag::err_union_member_of_reference_type) 7623 << NewFD->getDeclName() << EltTy; 7624 NewFD->setInvalidDecl(); 7625 } 7626 } 7627 } 7628 7629 // FIXME: We need to pass in the attributes given an AST 7630 // representation, not a parser representation. 7631 if (D) 7632 // FIXME: What to pass instead of TUScope? 7633 ProcessDeclAttributes(TUScope, NewFD, *D); 7634 7635 if (T.isObjCGCWeak()) 7636 Diag(Loc, diag::warn_attribute_weak_on_field); 7637 7638 NewFD->setAccess(AS); 7639 return NewFD; 7640} 7641 7642bool Sema::CheckNontrivialField(FieldDecl *FD) { 7643 assert(FD); 7644 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 7645 7646 if (FD->isInvalidDecl()) 7647 return true; 7648 7649 QualType EltTy = Context.getBaseElementType(FD->getType()); 7650 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7651 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7652 if (RDecl->getDefinition()) { 7653 // We check for copy constructors before constructors 7654 // because otherwise we'll never get complaints about 7655 // copy constructors. 7656 7657 CXXSpecialMember member = CXXInvalid; 7658 if (!RDecl->hasTrivialCopyConstructor()) 7659 member = CXXCopyConstructor; 7660 else if (!RDecl->hasTrivialConstructor()) 7661 member = CXXConstructor; 7662 else if (!RDecl->hasTrivialCopyAssignment()) 7663 member = CXXCopyAssignment; 7664 else if (!RDecl->hasTrivialDestructor()) 7665 member = CXXDestructor; 7666 7667 if (member != CXXInvalid) { 7668 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 7669 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 7670 DiagnoseNontrivial(RT, member); 7671 return true; 7672 } 7673 } 7674 } 7675 7676 return false; 7677} 7678 7679/// DiagnoseNontrivial - Given that a class has a non-trivial 7680/// special member, figure out why. 7681void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 7682 QualType QT(T, 0U); 7683 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 7684 7685 // Check whether the member was user-declared. 7686 switch (member) { 7687 case CXXInvalid: 7688 break; 7689 7690 case CXXConstructor: 7691 if (RD->hasUserDeclaredConstructor()) { 7692 typedef CXXRecordDecl::ctor_iterator ctor_iter; 7693 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 7694 const FunctionDecl *body = 0; 7695 ci->hasBody(body); 7696 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 7697 SourceLocation CtorLoc = ci->getLocation(); 7698 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7699 return; 7700 } 7701 } 7702 7703 assert(0 && "found no user-declared constructors"); 7704 return; 7705 } 7706 break; 7707 7708 case CXXCopyConstructor: 7709 if (RD->hasUserDeclaredCopyConstructor()) { 7710 SourceLocation CtorLoc = 7711 RD->getCopyConstructor(Context, 0)->getLocation(); 7712 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7713 return; 7714 } 7715 break; 7716 7717 case CXXCopyAssignment: 7718 if (RD->hasUserDeclaredCopyAssignment()) { 7719 // FIXME: this should use the location of the copy 7720 // assignment, not the type. 7721 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 7722 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 7723 return; 7724 } 7725 break; 7726 7727 case CXXDestructor: 7728 if (RD->hasUserDeclaredDestructor()) { 7729 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 7730 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7731 return; 7732 } 7733 break; 7734 } 7735 7736 typedef CXXRecordDecl::base_class_iterator base_iter; 7737 7738 // Virtual bases and members inhibit trivial copying/construction, 7739 // but not trivial destruction. 7740 if (member != CXXDestructor) { 7741 // Check for virtual bases. vbases includes indirect virtual bases, 7742 // so we just iterate through the direct bases. 7743 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 7744 if (bi->isVirtual()) { 7745 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7746 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 7747 return; 7748 } 7749 7750 // Check for virtual methods. 7751 typedef CXXRecordDecl::method_iterator meth_iter; 7752 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 7753 ++mi) { 7754 if (mi->isVirtual()) { 7755 SourceLocation MLoc = mi->getSourceRange().getBegin(); 7756 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 7757 return; 7758 } 7759 } 7760 } 7761 7762 bool (CXXRecordDecl::*hasTrivial)() const; 7763 switch (member) { 7764 case CXXConstructor: 7765 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 7766 case CXXCopyConstructor: 7767 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 7768 case CXXCopyAssignment: 7769 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 7770 case CXXDestructor: 7771 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 7772 default: 7773 assert(0 && "unexpected special member"); return; 7774 } 7775 7776 // Check for nontrivial bases (and recurse). 7777 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 7778 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 7779 assert(BaseRT && "Don't know how to handle dependent bases"); 7780 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 7781 if (!(BaseRecTy->*hasTrivial)()) { 7782 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7783 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 7784 DiagnoseNontrivial(BaseRT, member); 7785 return; 7786 } 7787 } 7788 7789 // Check for nontrivial members (and recurse). 7790 typedef RecordDecl::field_iterator field_iter; 7791 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 7792 ++fi) { 7793 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 7794 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 7795 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 7796 7797 if (!(EltRD->*hasTrivial)()) { 7798 SourceLocation FLoc = (*fi)->getLocation(); 7799 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 7800 DiagnoseNontrivial(EltRT, member); 7801 return; 7802 } 7803 } 7804 } 7805 7806 assert(0 && "found no explanation for non-trivial member"); 7807} 7808 7809/// TranslateIvarVisibility - Translate visibility from a token ID to an 7810/// AST enum value. 7811static ObjCIvarDecl::AccessControl 7812TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 7813 switch (ivarVisibility) { 7814 default: assert(0 && "Unknown visitibility kind"); 7815 case tok::objc_private: return ObjCIvarDecl::Private; 7816 case tok::objc_public: return ObjCIvarDecl::Public; 7817 case tok::objc_protected: return ObjCIvarDecl::Protected; 7818 case tok::objc_package: return ObjCIvarDecl::Package; 7819 } 7820} 7821 7822/// ActOnIvar - Each ivar field of an objective-c class is passed into this 7823/// in order to create an IvarDecl object for it. 7824Decl *Sema::ActOnIvar(Scope *S, 7825 SourceLocation DeclStart, 7826 Decl *IntfDecl, 7827 Declarator &D, ExprTy *BitfieldWidth, 7828 tok::ObjCKeywordKind Visibility) { 7829 7830 IdentifierInfo *II = D.getIdentifier(); 7831 Expr *BitWidth = (Expr*)BitfieldWidth; 7832 SourceLocation Loc = DeclStart; 7833 if (II) Loc = D.getIdentifierLoc(); 7834 7835 // FIXME: Unnamed fields can be handled in various different ways, for 7836 // example, unnamed unions inject all members into the struct namespace! 7837 7838 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7839 QualType T = TInfo->getType(); 7840 7841 if (BitWidth) { 7842 // 6.7.2.1p3, 6.7.2.1p4 7843 if (VerifyBitField(Loc, II, T, BitWidth)) { 7844 D.setInvalidType(); 7845 BitWidth = 0; 7846 } 7847 } else { 7848 // Not a bitfield. 7849 7850 // validate II. 7851 7852 } 7853 if (T->isReferenceType()) { 7854 Diag(Loc, diag::err_ivar_reference_type); 7855 D.setInvalidType(); 7856 } 7857 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7858 // than a variably modified type. 7859 else if (T->isVariablyModifiedType()) { 7860 Diag(Loc, diag::err_typecheck_ivar_variable_size); 7861 D.setInvalidType(); 7862 } 7863 7864 // Get the visibility (access control) for this ivar. 7865 ObjCIvarDecl::AccessControl ac = 7866 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 7867 : ObjCIvarDecl::None; 7868 // Must set ivar's DeclContext to its enclosing interface. 7869 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 7870 ObjCContainerDecl *EnclosingContext; 7871 if (ObjCImplementationDecl *IMPDecl = 7872 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7873 if (!LangOpts.ObjCNonFragileABI2) { 7874 // Case of ivar declared in an implementation. Context is that of its class. 7875 EnclosingContext = IMPDecl->getClassInterface(); 7876 assert(EnclosingContext && "Implementation has no class interface!"); 7877 } 7878 else 7879 EnclosingContext = EnclosingDecl; 7880 } else { 7881 if (ObjCCategoryDecl *CDecl = 7882 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7883 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 7884 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 7885 return 0; 7886 } 7887 } 7888 EnclosingContext = EnclosingDecl; 7889 } 7890 7891 // Construct the decl. 7892 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext, 7893 DeclStart, Loc, II, T, 7894 TInfo, ac, (Expr *)BitfieldWidth); 7895 7896 if (II) { 7897 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 7898 ForRedeclaration); 7899 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 7900 && !isa<TagDecl>(PrevDecl)) { 7901 Diag(Loc, diag::err_duplicate_member) << II; 7902 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7903 NewID->setInvalidDecl(); 7904 } 7905 } 7906 7907 // Process attributes attached to the ivar. 7908 ProcessDeclAttributes(S, NewID, D); 7909 7910 if (D.isInvalidType()) 7911 NewID->setInvalidDecl(); 7912 7913 if (II) { 7914 // FIXME: When interfaces are DeclContexts, we'll need to add 7915 // these to the interface. 7916 S->AddDecl(NewID); 7917 IdResolver.AddDecl(NewID); 7918 } 7919 7920 return NewID; 7921} 7922 7923/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 7924/// class and class extensions. For every class @interface and class 7925/// extension @interface, if the last ivar is a bitfield of any type, 7926/// then add an implicit `char :0` ivar to the end of that interface. 7927void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 7928 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 7929 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 7930 return; 7931 7932 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 7933 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 7934 7935 if (!Ivar->isBitField()) 7936 return; 7937 uint64_t BitFieldSize = 7938 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 7939 if (BitFieldSize == 0) 7940 return; 7941 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 7942 if (!ID) { 7943 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7944 if (!CD->IsClassExtension()) 7945 return; 7946 } 7947 // No need to add this to end of @implementation. 7948 else 7949 return; 7950 } 7951 // All conditions are met. Add a new bitfield to the tail end of ivars. 7952 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 7953 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 7954 7955 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 7956 DeclLoc, DeclLoc, 0, 7957 Context.CharTy, 7958 Context.CreateTypeSourceInfo(Context.CharTy), 7959 ObjCIvarDecl::Private, BW, 7960 true); 7961 AllIvarDecls.push_back(Ivar); 7962} 7963 7964void Sema::ActOnFields(Scope* S, 7965 SourceLocation RecLoc, Decl *EnclosingDecl, 7966 Decl **Fields, unsigned NumFields, 7967 SourceLocation LBrac, SourceLocation RBrac, 7968 AttributeList *Attr) { 7969 assert(EnclosingDecl && "missing record or interface decl"); 7970 7971 // If the decl this is being inserted into is invalid, then it may be a 7972 // redeclaration or some other bogus case. Don't try to add fields to it. 7973 if (EnclosingDecl->isInvalidDecl()) { 7974 // FIXME: Deallocate fields? 7975 return; 7976 } 7977 7978 7979 // Verify that all the fields are okay. 7980 unsigned NumNamedMembers = 0; 7981 llvm::SmallVector<FieldDecl*, 32> RecFields; 7982 7983 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 7984 for (unsigned i = 0; i != NumFields; ++i) { 7985 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 7986 7987 // Get the type for the field. 7988 const Type *FDTy = FD->getType().getTypePtr(); 7989 7990 if (!FD->isAnonymousStructOrUnion()) { 7991 // Remember all fields written by the user. 7992 RecFields.push_back(FD); 7993 } 7994 7995 // If the field is already invalid for some reason, don't emit more 7996 // diagnostics about it. 7997 if (FD->isInvalidDecl()) { 7998 EnclosingDecl->setInvalidDecl(); 7999 continue; 8000 } 8001 8002 // C99 6.7.2.1p2: 8003 // A structure or union shall not contain a member with 8004 // incomplete or function type (hence, a structure shall not 8005 // contain an instance of itself, but may contain a pointer to 8006 // an instance of itself), except that the last member of a 8007 // structure with more than one named member may have incomplete 8008 // array type; such a structure (and any union containing, 8009 // possibly recursively, a member that is such a structure) 8010 // shall not be a member of a structure or an element of an 8011 // array. 8012 if (FDTy->isFunctionType()) { 8013 // Field declared as a function. 8014 Diag(FD->getLocation(), diag::err_field_declared_as_function) 8015 << FD->getDeclName(); 8016 FD->setInvalidDecl(); 8017 EnclosingDecl->setInvalidDecl(); 8018 continue; 8019 } else if (FDTy->isIncompleteArrayType() && Record && 8020 ((i == NumFields - 1 && !Record->isUnion()) || 8021 ((getLangOptions().Microsoft || getLangOptions().CPlusPlus) && 8022 (i == NumFields - 1 || Record->isUnion())))) { 8023 // Flexible array member. 8024 // Microsoft and g++ is more permissive regarding flexible array. 8025 // It will accept flexible array in union and also 8026 // as the sole element of a struct/class. 8027 if (getLangOptions().Microsoft) { 8028 if (Record->isUnion()) 8029 Diag(FD->getLocation(), diag::ext_flexible_array_union_ms) 8030 << FD->getDeclName(); 8031 else if (NumFields == 1) 8032 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_ms) 8033 << FD->getDeclName() << Record->getTagKind(); 8034 } else if (getLangOptions().CPlusPlus) { 8035 if (Record->isUnion()) 8036 Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) 8037 << FD->getDeclName(); 8038 else if (NumFields == 1) 8039 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_gnu) 8040 << FD->getDeclName() << Record->getTagKind(); 8041 } else if (NumNamedMembers < 1) { 8042 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 8043 << FD->getDeclName(); 8044 FD->setInvalidDecl(); 8045 EnclosingDecl->setInvalidDecl(); 8046 continue; 8047 } 8048 if (!FD->getType()->isDependentType() && 8049 !Context.getBaseElementType(FD->getType())->isPODType()) { 8050 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 8051 << FD->getDeclName() << FD->getType(); 8052 FD->setInvalidDecl(); 8053 EnclosingDecl->setInvalidDecl(); 8054 continue; 8055 } 8056 // Okay, we have a legal flexible array member at the end of the struct. 8057 if (Record) 8058 Record->setHasFlexibleArrayMember(true); 8059 } else if (!FDTy->isDependentType() && 8060 RequireCompleteType(FD->getLocation(), FD->getType(), 8061 diag::err_field_incomplete)) { 8062 // Incomplete type 8063 FD->setInvalidDecl(); 8064 EnclosingDecl->setInvalidDecl(); 8065 continue; 8066 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 8067 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 8068 // If this is a member of a union, then entire union becomes "flexible". 8069 if (Record && Record->isUnion()) { 8070 Record->setHasFlexibleArrayMember(true); 8071 } else { 8072 // If this is a struct/class and this is not the last element, reject 8073 // it. Note that GCC supports variable sized arrays in the middle of 8074 // structures. 8075 if (i != NumFields-1) 8076 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 8077 << FD->getDeclName() << FD->getType(); 8078 else { 8079 // We support flexible arrays at the end of structs in 8080 // other structs as an extension. 8081 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 8082 << FD->getDeclName(); 8083 if (Record) 8084 Record->setHasFlexibleArrayMember(true); 8085 } 8086 } 8087 } 8088 if (Record && FDTTy->getDecl()->hasObjectMember()) 8089 Record->setHasObjectMember(true); 8090 } else if (FDTy->isObjCObjectType()) { 8091 /// A field cannot be an Objective-c object 8092 Diag(FD->getLocation(), diag::err_statically_allocated_object); 8093 FD->setInvalidDecl(); 8094 EnclosingDecl->setInvalidDecl(); 8095 continue; 8096 } else if (getLangOptions().ObjC1 && 8097 getLangOptions().getGCMode() != LangOptions::NonGC && 8098 Record && 8099 (FD->getType()->isObjCObjectPointerType() || 8100 FD->getType().isObjCGCStrong())) 8101 Record->setHasObjectMember(true); 8102 else if (Context.getAsArrayType(FD->getType())) { 8103 QualType BaseType = Context.getBaseElementType(FD->getType()); 8104 if (Record && BaseType->isRecordType() && 8105 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 8106 Record->setHasObjectMember(true); 8107 } 8108 // Keep track of the number of named members. 8109 if (FD->getIdentifier()) 8110 ++NumNamedMembers; 8111 } 8112 8113 // Okay, we successfully defined 'Record'. 8114 if (Record) { 8115 bool Completed = false; 8116 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 8117 if (!CXXRecord->isInvalidDecl()) { 8118 // Set access bits correctly on the directly-declared conversions. 8119 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 8120 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 8121 I != E; ++I) 8122 Convs->setAccess(I, (*I)->getAccess()); 8123 8124 if (!CXXRecord->isDependentType()) { 8125 // Add any implicitly-declared members to this class. 8126 AddImplicitlyDeclaredMembersToClass(CXXRecord); 8127 8128 // If we have virtual base classes, we may end up finding multiple 8129 // final overriders for a given virtual function. Check for this 8130 // problem now. 8131 if (CXXRecord->getNumVBases()) { 8132 CXXFinalOverriderMap FinalOverriders; 8133 CXXRecord->getFinalOverriders(FinalOverriders); 8134 8135 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 8136 MEnd = FinalOverriders.end(); 8137 M != MEnd; ++M) { 8138 for (OverridingMethods::iterator SO = M->second.begin(), 8139 SOEnd = M->second.end(); 8140 SO != SOEnd; ++SO) { 8141 assert(SO->second.size() > 0 && 8142 "Virtual function without overridding functions?"); 8143 if (SO->second.size() == 1) 8144 continue; 8145 8146 // C++ [class.virtual]p2: 8147 // In a derived class, if a virtual member function of a base 8148 // class subobject has more than one final overrider the 8149 // program is ill-formed. 8150 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 8151 << (NamedDecl *)M->first << Record; 8152 Diag(M->first->getLocation(), 8153 diag::note_overridden_virtual_function); 8154 for (OverridingMethods::overriding_iterator 8155 OM = SO->second.begin(), 8156 OMEnd = SO->second.end(); 8157 OM != OMEnd; ++OM) 8158 Diag(OM->Method->getLocation(), diag::note_final_overrider) 8159 << (NamedDecl *)M->first << OM->Method->getParent(); 8160 8161 Record->setInvalidDecl(); 8162 } 8163 } 8164 CXXRecord->completeDefinition(&FinalOverriders); 8165 Completed = true; 8166 } 8167 } 8168 } 8169 } 8170 8171 if (!Completed) 8172 Record->completeDefinition(); 8173 } else { 8174 ObjCIvarDecl **ClsFields = 8175 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 8176 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 8177 ID->setLocEnd(RBrac); 8178 // Add ivar's to class's DeclContext. 8179 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 8180 ClsFields[i]->setLexicalDeclContext(ID); 8181 ID->addDecl(ClsFields[i]); 8182 } 8183 // Must enforce the rule that ivars in the base classes may not be 8184 // duplicates. 8185 if (ID->getSuperClass()) 8186 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 8187 } else if (ObjCImplementationDecl *IMPDecl = 8188 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 8189 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 8190 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 8191 // Ivar declared in @implementation never belongs to the implementation. 8192 // Only it is in implementation's lexical context. 8193 ClsFields[I]->setLexicalDeclContext(IMPDecl); 8194 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 8195 } else if (ObjCCategoryDecl *CDecl = 8196 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 8197 // case of ivars in class extension; all other cases have been 8198 // reported as errors elsewhere. 8199 // FIXME. Class extension does not have a LocEnd field. 8200 // CDecl->setLocEnd(RBrac); 8201 // Add ivar's to class extension's DeclContext. 8202 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 8203 ClsFields[i]->setLexicalDeclContext(CDecl); 8204 CDecl->addDecl(ClsFields[i]); 8205 } 8206 } 8207 } 8208 8209 if (Attr) 8210 ProcessDeclAttributeList(S, Record, Attr); 8211 8212 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 8213 // set the visibility of this record. 8214 if (Record && !Record->getDeclContext()->isRecord()) 8215 AddPushedVisibilityAttribute(Record); 8216} 8217 8218/// \brief Determine whether the given integral value is representable within 8219/// the given type T. 8220static bool isRepresentableIntegerValue(ASTContext &Context, 8221 llvm::APSInt &Value, 8222 QualType T) { 8223 assert(T->isIntegralType(Context) && "Integral type required!"); 8224 unsigned BitWidth = Context.getIntWidth(T); 8225 8226 if (Value.isUnsigned() || Value.isNonNegative()) { 8227 if (T->isSignedIntegerType()) 8228 --BitWidth; 8229 return Value.getActiveBits() <= BitWidth; 8230 } 8231 return Value.getMinSignedBits() <= BitWidth; 8232} 8233 8234// \brief Given an integral type, return the next larger integral type 8235// (or a NULL type of no such type exists). 8236static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 8237 // FIXME: Int128/UInt128 support, which also needs to be introduced into 8238 // enum checking below. 8239 assert(T->isIntegralType(Context) && "Integral type required!"); 8240 const unsigned NumTypes = 4; 8241 QualType SignedIntegralTypes[NumTypes] = { 8242 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 8243 }; 8244 QualType UnsignedIntegralTypes[NumTypes] = { 8245 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 8246 Context.UnsignedLongLongTy 8247 }; 8248 8249 unsigned BitWidth = Context.getTypeSize(T); 8250 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 8251 : UnsignedIntegralTypes; 8252 for (unsigned I = 0; I != NumTypes; ++I) 8253 if (Context.getTypeSize(Types[I]) > BitWidth) 8254 return Types[I]; 8255 8256 return QualType(); 8257} 8258 8259EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 8260 EnumConstantDecl *LastEnumConst, 8261 SourceLocation IdLoc, 8262 IdentifierInfo *Id, 8263 Expr *Val) { 8264 unsigned IntWidth = Context.Target.getIntWidth(); 8265 llvm::APSInt EnumVal(IntWidth); 8266 QualType EltTy; 8267 8268 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) 8269 Val = 0; 8270 8271 if (Val) { 8272 if (Enum->isDependentType() || Val->isTypeDependent()) 8273 EltTy = Context.DependentTy; 8274 else { 8275 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 8276 SourceLocation ExpLoc; 8277 if (!Val->isValueDependent() && 8278 VerifyIntegerConstantExpression(Val, &EnumVal)) { 8279 Val = 0; 8280 } else { 8281 if (!getLangOptions().CPlusPlus) { 8282 // C99 6.7.2.2p2: 8283 // The expression that defines the value of an enumeration constant 8284 // shall be an integer constant expression that has a value 8285 // representable as an int. 8286 8287 // Complain if the value is not representable in an int. 8288 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 8289 Diag(IdLoc, diag::ext_enum_value_not_int) 8290 << EnumVal.toString(10) << Val->getSourceRange() 8291 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 8292 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 8293 // Force the type of the expression to 'int'. 8294 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).take(); 8295 } 8296 } 8297 8298 if (Enum->isFixed()) { 8299 EltTy = Enum->getIntegerType(); 8300 8301 // C++0x [dcl.enum]p5: 8302 // ... if the initializing value of an enumerator cannot be 8303 // represented by the underlying type, the program is ill-formed. 8304 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 8305 if (getLangOptions().Microsoft) { 8306 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 8307 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 8308 } else 8309 Diag(IdLoc, diag::err_enumerator_too_large) 8310 << EltTy; 8311 } else 8312 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 8313 } 8314 else { 8315 // C++0x [dcl.enum]p5: 8316 // If the underlying type is not fixed, the type of each enumerator 8317 // is the type of its initializing value: 8318 // - If an initializer is specified for an enumerator, the 8319 // initializing value has the same type as the expression. 8320 EltTy = Val->getType(); 8321 } 8322 } 8323 } 8324 } 8325 8326 if (!Val) { 8327 if (Enum->isDependentType()) 8328 EltTy = Context.DependentTy; 8329 else if (!LastEnumConst) { 8330 // C++0x [dcl.enum]p5: 8331 // If the underlying type is not fixed, the type of each enumerator 8332 // is the type of its initializing value: 8333 // - If no initializer is specified for the first enumerator, the 8334 // initializing value has an unspecified integral type. 8335 // 8336 // GCC uses 'int' for its unspecified integral type, as does 8337 // C99 6.7.2.2p3. 8338 if (Enum->isFixed()) { 8339 EltTy = Enum->getIntegerType(); 8340 } 8341 else { 8342 EltTy = Context.IntTy; 8343 } 8344 } else { 8345 // Assign the last value + 1. 8346 EnumVal = LastEnumConst->getInitVal(); 8347 ++EnumVal; 8348 EltTy = LastEnumConst->getType(); 8349 8350 // Check for overflow on increment. 8351 if (EnumVal < LastEnumConst->getInitVal()) { 8352 // C++0x [dcl.enum]p5: 8353 // If the underlying type is not fixed, the type of each enumerator 8354 // is the type of its initializing value: 8355 // 8356 // - Otherwise the type of the initializing value is the same as 8357 // the type of the initializing value of the preceding enumerator 8358 // unless the incremented value is not representable in that type, 8359 // in which case the type is an unspecified integral type 8360 // sufficient to contain the incremented value. If no such type 8361 // exists, the program is ill-formed. 8362 QualType T = getNextLargerIntegralType(Context, EltTy); 8363 if (T.isNull() || Enum->isFixed()) { 8364 // There is no integral type larger enough to represent this 8365 // value. Complain, then allow the value to wrap around. 8366 EnumVal = LastEnumConst->getInitVal(); 8367 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); 8368 ++EnumVal; 8369 if (Enum->isFixed()) 8370 // When the underlying type is fixed, this is ill-formed. 8371 Diag(IdLoc, diag::err_enumerator_wrapped) 8372 << EnumVal.toString(10) 8373 << EltTy; 8374 else 8375 Diag(IdLoc, diag::warn_enumerator_too_large) 8376 << EnumVal.toString(10); 8377 } else { 8378 EltTy = T; 8379 } 8380 8381 // Retrieve the last enumerator's value, extent that type to the 8382 // type that is supposed to be large enough to represent the incremented 8383 // value, then increment. 8384 EnumVal = LastEnumConst->getInitVal(); 8385 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 8386 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 8387 ++EnumVal; 8388 8389 // If we're not in C++, diagnose the overflow of enumerator values, 8390 // which in C99 means that the enumerator value is not representable in 8391 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 8392 // permits enumerator values that are representable in some larger 8393 // integral type. 8394 if (!getLangOptions().CPlusPlus && !T.isNull()) 8395 Diag(IdLoc, diag::warn_enum_value_overflow); 8396 } else if (!getLangOptions().CPlusPlus && 8397 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 8398 // Enforce C99 6.7.2.2p2 even when we compute the next value. 8399 Diag(IdLoc, diag::ext_enum_value_not_int) 8400 << EnumVal.toString(10) << 1; 8401 } 8402 } 8403 } 8404 8405 if (!EltTy->isDependentType()) { 8406 // Make the enumerator value match the signedness and size of the 8407 // enumerator's type. 8408 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 8409 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 8410 } 8411 8412 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 8413 Val, EnumVal); 8414} 8415 8416 8417Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 8418 SourceLocation IdLoc, IdentifierInfo *Id, 8419 AttributeList *Attr, 8420 SourceLocation EqualLoc, ExprTy *val) { 8421 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 8422 EnumConstantDecl *LastEnumConst = 8423 cast_or_null<EnumConstantDecl>(lastEnumConst); 8424 Expr *Val = static_cast<Expr*>(val); 8425 8426 // The scope passed in may not be a decl scope. Zip up the scope tree until 8427 // we find one that is. 8428 S = getNonFieldDeclScope(S); 8429 8430 // Verify that there isn't already something declared with this name in this 8431 // scope. 8432 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 8433 ForRedeclaration); 8434 if (PrevDecl && PrevDecl->isTemplateParameter()) { 8435 // Maybe we will complain about the shadowed template parameter. 8436 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 8437 // Just pretend that we didn't see the previous declaration. 8438 PrevDecl = 0; 8439 } 8440 8441 if (PrevDecl) { 8442 // When in C++, we may get a TagDecl with the same name; in this case the 8443 // enum constant will 'hide' the tag. 8444 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 8445 "Received TagDecl when not in C++!"); 8446 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 8447 if (isa<EnumConstantDecl>(PrevDecl)) 8448 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 8449 else 8450 Diag(IdLoc, diag::err_redefinition) << Id; 8451 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 8452 return 0; 8453 } 8454 } 8455 8456 // C++ [class.mem]p13: 8457 // If T is the name of a class, then each of the following shall have a 8458 // name different from T: 8459 // - every enumerator of every member of class T that is an enumerated 8460 // type 8461 if (CXXRecordDecl *Record 8462 = dyn_cast<CXXRecordDecl>( 8463 TheEnumDecl->getDeclContext()->getRedeclContext())) 8464 if (Record->getIdentifier() && Record->getIdentifier() == Id) 8465 Diag(IdLoc, diag::err_member_name_of_class) << Id; 8466 8467 EnumConstantDecl *New = 8468 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 8469 8470 if (New) { 8471 // Process attributes. 8472 if (Attr) ProcessDeclAttributeList(S, New, Attr); 8473 8474 // Register this decl in the current scope stack. 8475 New->setAccess(TheEnumDecl->getAccess()); 8476 PushOnScopeChains(New, S); 8477 } 8478 8479 return New; 8480} 8481 8482void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 8483 SourceLocation RBraceLoc, Decl *EnumDeclX, 8484 Decl **Elements, unsigned NumElements, 8485 Scope *S, AttributeList *Attr) { 8486 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 8487 QualType EnumType = Context.getTypeDeclType(Enum); 8488 8489 if (Attr) 8490 ProcessDeclAttributeList(S, Enum, Attr); 8491 8492 if (Enum->isDependentType()) { 8493 for (unsigned i = 0; i != NumElements; ++i) { 8494 EnumConstantDecl *ECD = 8495 cast_or_null<EnumConstantDecl>(Elements[i]); 8496 if (!ECD) continue; 8497 8498 ECD->setType(EnumType); 8499 } 8500 8501 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 8502 return; 8503 } 8504 8505 // TODO: If the result value doesn't fit in an int, it must be a long or long 8506 // long value. ISO C does not support this, but GCC does as an extension, 8507 // emit a warning. 8508 unsigned IntWidth = Context.Target.getIntWidth(); 8509 unsigned CharWidth = Context.Target.getCharWidth(); 8510 unsigned ShortWidth = Context.Target.getShortWidth(); 8511 8512 // Verify that all the values are okay, compute the size of the values, and 8513 // reverse the list. 8514 unsigned NumNegativeBits = 0; 8515 unsigned NumPositiveBits = 0; 8516 8517 // Keep track of whether all elements have type int. 8518 bool AllElementsInt = true; 8519 8520 for (unsigned i = 0; i != NumElements; ++i) { 8521 EnumConstantDecl *ECD = 8522 cast_or_null<EnumConstantDecl>(Elements[i]); 8523 if (!ECD) continue; // Already issued a diagnostic. 8524 8525 const llvm::APSInt &InitVal = ECD->getInitVal(); 8526 8527 // Keep track of the size of positive and negative values. 8528 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 8529 NumPositiveBits = std::max(NumPositiveBits, 8530 (unsigned)InitVal.getActiveBits()); 8531 else 8532 NumNegativeBits = std::max(NumNegativeBits, 8533 (unsigned)InitVal.getMinSignedBits()); 8534 8535 // Keep track of whether every enum element has type int (very commmon). 8536 if (AllElementsInt) 8537 AllElementsInt = ECD->getType() == Context.IntTy; 8538 } 8539 8540 // Figure out the type that should be used for this enum. 8541 QualType BestType; 8542 unsigned BestWidth; 8543 8544 // C++0x N3000 [conv.prom]p3: 8545 // An rvalue of an unscoped enumeration type whose underlying 8546 // type is not fixed can be converted to an rvalue of the first 8547 // of the following types that can represent all the values of 8548 // the enumeration: int, unsigned int, long int, unsigned long 8549 // int, long long int, or unsigned long long int. 8550 // C99 6.4.4.3p2: 8551 // An identifier declared as an enumeration constant has type int. 8552 // The C99 rule is modified by a gcc extension 8553 QualType BestPromotionType; 8554 8555 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 8556 // -fshort-enums is the equivalent to specifying the packed attribute on all 8557 // enum definitions. 8558 if (LangOpts.ShortEnums) 8559 Packed = true; 8560 8561 if (Enum->isFixed()) { 8562 BestType = BestPromotionType = Enum->getIntegerType(); 8563 // We don't need to set BestWidth, because BestType is going to be the type 8564 // of the enumerators, but we do anyway because otherwise some compilers 8565 // warn that it might be used uninitialized. 8566 BestWidth = CharWidth; 8567 } 8568 else if (NumNegativeBits) { 8569 // If there is a negative value, figure out the smallest integer type (of 8570 // int/long/longlong) that fits. 8571 // If it's packed, check also if it fits a char or a short. 8572 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 8573 BestType = Context.SignedCharTy; 8574 BestWidth = CharWidth; 8575 } else if (Packed && NumNegativeBits <= ShortWidth && 8576 NumPositiveBits < ShortWidth) { 8577 BestType = Context.ShortTy; 8578 BestWidth = ShortWidth; 8579 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 8580 BestType = Context.IntTy; 8581 BestWidth = IntWidth; 8582 } else { 8583 BestWidth = Context.Target.getLongWidth(); 8584 8585 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 8586 BestType = Context.LongTy; 8587 } else { 8588 BestWidth = Context.Target.getLongLongWidth(); 8589 8590 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 8591 Diag(Enum->getLocation(), diag::warn_enum_too_large); 8592 BestType = Context.LongLongTy; 8593 } 8594 } 8595 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 8596 } else { 8597 // If there is no negative value, figure out the smallest type that fits 8598 // all of the enumerator values. 8599 // If it's packed, check also if it fits a char or a short. 8600 if (Packed && NumPositiveBits <= CharWidth) { 8601 BestType = Context.UnsignedCharTy; 8602 BestPromotionType = Context.IntTy; 8603 BestWidth = CharWidth; 8604 } else if (Packed && NumPositiveBits <= ShortWidth) { 8605 BestType = Context.UnsignedShortTy; 8606 BestPromotionType = Context.IntTy; 8607 BestWidth = ShortWidth; 8608 } else if (NumPositiveBits <= IntWidth) { 8609 BestType = Context.UnsignedIntTy; 8610 BestWidth = IntWidth; 8611 BestPromotionType 8612 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8613 ? Context.UnsignedIntTy : Context.IntTy; 8614 } else if (NumPositiveBits <= 8615 (BestWidth = Context.Target.getLongWidth())) { 8616 BestType = Context.UnsignedLongTy; 8617 BestPromotionType 8618 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8619 ? Context.UnsignedLongTy : Context.LongTy; 8620 } else { 8621 BestWidth = Context.Target.getLongLongWidth(); 8622 assert(NumPositiveBits <= BestWidth && 8623 "How could an initializer get larger than ULL?"); 8624 BestType = Context.UnsignedLongLongTy; 8625 BestPromotionType 8626 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8627 ? Context.UnsignedLongLongTy : Context.LongLongTy; 8628 } 8629 } 8630 8631 // Loop over all of the enumerator constants, changing their types to match 8632 // the type of the enum if needed. 8633 for (unsigned i = 0; i != NumElements; ++i) { 8634 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 8635 if (!ECD) continue; // Already issued a diagnostic. 8636 8637 // Standard C says the enumerators have int type, but we allow, as an 8638 // extension, the enumerators to be larger than int size. If each 8639 // enumerator value fits in an int, type it as an int, otherwise type it the 8640 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 8641 // that X has type 'int', not 'unsigned'. 8642 8643 // Determine whether the value fits into an int. 8644 llvm::APSInt InitVal = ECD->getInitVal(); 8645 8646 // If it fits into an integer type, force it. Otherwise force it to match 8647 // the enum decl type. 8648 QualType NewTy; 8649 unsigned NewWidth; 8650 bool NewSign; 8651 if (!getLangOptions().CPlusPlus && 8652 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 8653 NewTy = Context.IntTy; 8654 NewWidth = IntWidth; 8655 NewSign = true; 8656 } else if (ECD->getType() == BestType) { 8657 // Already the right type! 8658 if (getLangOptions().CPlusPlus) 8659 // C++ [dcl.enum]p4: Following the closing brace of an 8660 // enum-specifier, each enumerator has the type of its 8661 // enumeration. 8662 ECD->setType(EnumType); 8663 continue; 8664 } else { 8665 NewTy = BestType; 8666 NewWidth = BestWidth; 8667 NewSign = BestType->isSignedIntegerType(); 8668 } 8669 8670 // Adjust the APSInt value. 8671 InitVal = InitVal.extOrTrunc(NewWidth); 8672 InitVal.setIsSigned(NewSign); 8673 ECD->setInitVal(InitVal); 8674 8675 // Adjust the Expr initializer and type. 8676 if (ECD->getInitExpr() && 8677 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) 8678 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 8679 CK_IntegralCast, 8680 ECD->getInitExpr(), 8681 /*base paths*/ 0, 8682 VK_RValue)); 8683 if (getLangOptions().CPlusPlus) 8684 // C++ [dcl.enum]p4: Following the closing brace of an 8685 // enum-specifier, each enumerator has the type of its 8686 // enumeration. 8687 ECD->setType(EnumType); 8688 else 8689 ECD->setType(NewTy); 8690 } 8691 8692 Enum->completeDefinition(BestType, BestPromotionType, 8693 NumPositiveBits, NumNegativeBits); 8694} 8695 8696Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, 8697 SourceLocation StartLoc, 8698 SourceLocation EndLoc) { 8699 StringLiteral *AsmString = cast<StringLiteral>(expr); 8700 8701 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 8702 AsmString, StartLoc, 8703 EndLoc); 8704 CurContext->addDecl(New); 8705 return New; 8706} 8707 8708void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 8709 SourceLocation PragmaLoc, 8710 SourceLocation NameLoc) { 8711 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 8712 8713 if (PrevDecl) { 8714 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 8715 } else { 8716 (void)WeakUndeclaredIdentifiers.insert( 8717 std::pair<IdentifierInfo*,WeakInfo> 8718 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 8719 } 8720} 8721 8722void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 8723 IdentifierInfo* AliasName, 8724 SourceLocation PragmaLoc, 8725 SourceLocation NameLoc, 8726 SourceLocation AliasNameLoc) { 8727 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 8728 LookupOrdinaryName); 8729 WeakInfo W = WeakInfo(Name, NameLoc); 8730 8731 if (PrevDecl) { 8732 if (!PrevDecl->hasAttr<AliasAttr>()) 8733 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 8734 DeclApplyPragmaWeak(TUScope, ND, W); 8735 } else { 8736 (void)WeakUndeclaredIdentifiers.insert( 8737 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 8738 } 8739} 8740