SemaDecl.cpp revision 7d99e989c1a20e358f472e35d615313f2fe223db
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 "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 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. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isNotEmpty()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, 91 // so build a dependent node to describe the type. 92 return CheckTypenameType(ETK_None, 93 (NestedNameSpecifier *)SS->getScopeRep(), II, 94 SourceLocation(), SS->getRange(), NameLoc 95 ).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && 102 RequireCompleteDeclContext(*SS, LookupCtx)) 103 return 0; 104 } 105 106 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 107 // lookup for class-names. 108 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 109 LookupOrdinaryName; 110 LookupResult Result(*this, &II, NameLoc, Kind); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::NotFoundInCurrentInstantiation: 136 case LookupResult::FoundOverloaded: 137 case LookupResult::FoundUnresolvedValue: 138 Result.suppressDiagnostics(); 139 return 0; 140 141 case LookupResult::Ambiguous: 142 // Recover from type-hiding ambiguities by hiding the type. We'll 143 // do the lookup again when looking for an object, and we can 144 // diagnose the error then. If we don't do this, then the error 145 // about hiding the type will be immediately followed by an error 146 // that only makes sense if the identifier was treated like a type. 147 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 148 Result.suppressDiagnostics(); 149 return 0; 150 } 151 152 // Look to see if we have a type anywhere in the list of results. 153 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 154 Res != ResEnd; ++Res) { 155 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 156 if (!IIDecl || 157 (*Res)->getLocation().getRawEncoding() < 158 IIDecl->getLocation().getRawEncoding()) 159 IIDecl = *Res; 160 } 161 } 162 163 if (!IIDecl) { 164 // None of the entities we found is a type, so there is no way 165 // to even assume that the result is a type. In this case, don't 166 // complain about the ambiguity. The parser will either try to 167 // perform this lookup again (e.g., as an object name), which 168 // will produce the ambiguity, or will complain that it expected 169 // a type name. 170 Result.suppressDiagnostics(); 171 return 0; 172 } 173 174 // We found a type within the ambiguous lookup; diagnose the 175 // ambiguity and then return that type. This might be the right 176 // answer, or it might not be, but it suppresses any attempt to 177 // perform the name lookup again. 178 break; 179 180 case LookupResult::Found: 181 IIDecl = Result.getFoundDecl(); 182 break; 183 } 184 185 assert(IIDecl && "Didn't find decl"); 186 187 QualType T; 188 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 189 DiagnoseUseOfDecl(IIDecl, NameLoc); 190 191 if (T.isNull()) 192 T = Context.getTypeDeclType(TD); 193 194 if (SS) 195 T = getElaboratedType(ETK_None, *SS, T); 196 197 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 198 T = Context.getObjCInterfaceType(IDecl); 199 } else { 200 // If it's not plausibly a type, suppress diagnostics. 201 Result.suppressDiagnostics(); 202 return 0; 203 } 204 205 return T.getAsOpaquePtr(); 206} 207 208/// isTagName() - This method is called *for error recovery purposes only* 209/// to determine if the specified name is a valid tag name ("struct foo"). If 210/// so, this returns the TST for the tag corresponding to it (TST_enum, 211/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 212/// where the user forgot to specify the tag. 213DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 214 // Do a tag name lookup in this scope. 215 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 216 LookupName(R, S, false); 217 R.suppressDiagnostics(); 218 if (R.getResultKind() == LookupResult::Found) 219 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 220 switch (TD->getTagKind()) { 221 default: return DeclSpec::TST_unspecified; 222 case TTK_Struct: return DeclSpec::TST_struct; 223 case TTK_Union: return DeclSpec::TST_union; 224 case TTK_Class: return DeclSpec::TST_class; 225 case TTK_Enum: return DeclSpec::TST_enum; 226 } 227 } 228 229 return DeclSpec::TST_unspecified; 230} 231 232bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 233 SourceLocation IILoc, 234 Scope *S, 235 CXXScopeSpec *SS, 236 TypeTy *&SuggestedType) { 237 // We don't have anything to suggest (yet). 238 SuggestedType = 0; 239 240 // There may have been a typo in the name of the type. Look up typo 241 // results, in case we have something that we can suggest. 242 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 243 NotForRedeclaration); 244 245 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 246 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 247 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 248 !Result->isInvalidDecl()) { 249 // We found a similarly-named type or interface; suggest that. 250 if (!SS || !SS->isSet()) 251 Diag(IILoc, diag::err_unknown_typename_suggest) 252 << &II << Lookup.getLookupName() 253 << FixItHint::CreateReplacement(SourceRange(IILoc), 254 Result->getNameAsString()); 255 else if (DeclContext *DC = computeDeclContext(*SS, false)) 256 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 257 << &II << DC << Lookup.getLookupName() << SS->getRange() 258 << FixItHint::CreateReplacement(SourceRange(IILoc), 259 Result->getNameAsString()); 260 else 261 llvm_unreachable("could not have corrected a typo here"); 262 263 Diag(Result->getLocation(), diag::note_previous_decl) 264 << Result->getDeclName(); 265 266 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 267 return true; 268 } 269 } else if (Lookup.empty()) { 270 // We corrected to a keyword. 271 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 272 Diag(IILoc, diag::err_unknown_typename_suggest) 273 << &II << Corrected; 274 return true; 275 } 276 } 277 278 if (getLangOptions().CPlusPlus) { 279 // See if II is a class template that the user forgot to pass arguments to. 280 UnqualifiedId Name; 281 Name.setIdentifier(&II, IILoc); 282 CXXScopeSpec EmptySS; 283 TemplateTy TemplateResult; 284 bool MemberOfUnknownSpecialization; 285 if (isTemplateName(S, SS ? *SS : EmptySS, Name, 0, true, TemplateResult, 286 MemberOfUnknownSpecialization) == TNK_Type_template) { 287 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 288 Diag(IILoc, diag::err_template_missing_args) << TplName; 289 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 290 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 291 << TplDecl->getTemplateParameters()->getSourceRange(); 292 } 293 return true; 294 } 295 } 296 297 // FIXME: Should we move the logic that tries to recover from a missing tag 298 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 299 300 if (!SS || (!SS->isSet() && !SS->isInvalid())) 301 Diag(IILoc, diag::err_unknown_typename) << &II; 302 else if (DeclContext *DC = computeDeclContext(*SS, false)) 303 Diag(IILoc, diag::err_typename_nested_not_found) 304 << &II << DC << SS->getRange(); 305 else if (isDependentScopeSpecifier(*SS)) { 306 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 307 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 308 << SourceRange(SS->getRange().getBegin(), IILoc) 309 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 310 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 311 } else { 312 assert(SS && SS->isInvalid() && 313 "Invalid scope specifier has already been diagnosed"); 314 } 315 316 return true; 317} 318 319// Determines the context to return to after temporarily entering a 320// context. This depends in an unnecessarily complicated way on the 321// exact ordering of callbacks from the parser. 322DeclContext *Sema::getContainingDC(DeclContext *DC) { 323 324 // Functions defined inline within classes aren't parsed until we've 325 // finished parsing the top-level class, so the top-level class is 326 // the context we'll need to return to. 327 if (isa<FunctionDecl>(DC)) { 328 DC = DC->getLexicalParent(); 329 330 // A function not defined within a class will always return to its 331 // lexical context. 332 if (!isa<CXXRecordDecl>(DC)) 333 return DC; 334 335 // A C++ inline method/friend is parsed *after* the topmost class 336 // it was declared in is fully parsed ("complete"); the topmost 337 // class is the context we need to return to. 338 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 339 DC = RD; 340 341 // Return the declaration context of the topmost class the inline method is 342 // declared in. 343 return DC; 344 } 345 346 if (isa<ObjCMethodDecl>(DC)) 347 return Context.getTranslationUnitDecl(); 348 349 return DC->getLexicalParent(); 350} 351 352void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 353 assert(getContainingDC(DC) == CurContext && 354 "The next DeclContext should be lexically contained in the current one."); 355 CurContext = DC; 356 S->setEntity(DC); 357} 358 359void Sema::PopDeclContext() { 360 assert(CurContext && "DeclContext imbalance!"); 361 362 CurContext = getContainingDC(CurContext); 363} 364 365/// EnterDeclaratorContext - Used when we must lookup names in the context 366/// of a declarator's nested name specifier. 367/// 368void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 369 // C++0x [basic.lookup.unqual]p13: 370 // A name used in the definition of a static data member of class 371 // X (after the qualified-id of the static member) is looked up as 372 // if the name was used in a member function of X. 373 // C++0x [basic.lookup.unqual]p14: 374 // If a variable member of a namespace is defined outside of the 375 // scope of its namespace then any name used in the definition of 376 // the variable member (after the declarator-id) is looked up as 377 // if the definition of the variable member occurred in its 378 // namespace. 379 // Both of these imply that we should push a scope whose context 380 // is the semantic context of the declaration. We can't use 381 // PushDeclContext here because that context is not necessarily 382 // lexically contained in the current context. Fortunately, 383 // the containing scope should have the appropriate information. 384 385 assert(!S->getEntity() && "scope already has entity"); 386 387#ifndef NDEBUG 388 Scope *Ancestor = S->getParent(); 389 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 390 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 391#endif 392 393 CurContext = DC; 394 S->setEntity(DC); 395} 396 397void Sema::ExitDeclaratorContext(Scope *S) { 398 assert(S->getEntity() == CurContext && "Context imbalance!"); 399 400 // Switch back to the lexical context. The safety of this is 401 // enforced by an assert in EnterDeclaratorContext. 402 Scope *Ancestor = S->getParent(); 403 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 404 CurContext = (DeclContext*) Ancestor->getEntity(); 405 406 // We don't need to do anything with the scope, which is going to 407 // disappear. 408} 409 410/// \brief Determine whether we allow overloading of the function 411/// PrevDecl with another declaration. 412/// 413/// This routine determines whether overloading is possible, not 414/// whether some new function is actually an overload. It will return 415/// true in C++ (where we can always provide overloads) or, as an 416/// extension, in C when the previous function is already an 417/// overloaded function declaration or has the "overloadable" 418/// attribute. 419static bool AllowOverloadingOfFunction(LookupResult &Previous, 420 ASTContext &Context) { 421 if (Context.getLangOptions().CPlusPlus) 422 return true; 423 424 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 425 return true; 426 427 return (Previous.getResultKind() == LookupResult::Found 428 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 429} 430 431/// Add this decl to the scope shadowed decl chains. 432void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 433 // Move up the scope chain until we find the nearest enclosing 434 // non-transparent context. The declaration will be introduced into this 435 // scope. 436 while (S->getEntity() && 437 ((DeclContext *)S->getEntity())->isTransparentContext()) 438 S = S->getParent(); 439 440 // Add scoped declarations into their context, so that they can be 441 // found later. Declarations without a context won't be inserted 442 // into any context. 443 if (AddToContext) 444 CurContext->addDecl(D); 445 446 // Out-of-line definitions shouldn't be pushed into scope in C++. 447 // Out-of-line variable and function definitions shouldn't even in C. 448 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 449 D->isOutOfLine()) 450 return; 451 452 // Template instantiations should also not be pushed into scope. 453 if (isa<FunctionDecl>(D) && 454 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 455 return; 456 457 // If this replaces anything in the current scope, 458 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 459 IEnd = IdResolver.end(); 460 for (; I != IEnd; ++I) { 461 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 462 S->RemoveDecl(DeclPtrTy::make(*I)); 463 IdResolver.RemoveDecl(*I); 464 465 // Should only need to replace one decl. 466 break; 467 } 468 } 469 470 S->AddDecl(DeclPtrTy::make(D)); 471 IdResolver.AddDecl(D); 472} 473 474bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 475 return IdResolver.isDeclInScope(D, Ctx, Context, S); 476} 477 478static bool isOutOfScopePreviousDeclaration(NamedDecl *, 479 DeclContext*, 480 ASTContext&); 481 482/// Filters out lookup results that don't fall within the given scope 483/// as determined by isDeclInScope. 484static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 485 DeclContext *Ctx, Scope *S, 486 bool ConsiderLinkage) { 487 LookupResult::Filter F = R.makeFilter(); 488 while (F.hasNext()) { 489 NamedDecl *D = F.next(); 490 491 if (SemaRef.isDeclInScope(D, Ctx, S)) 492 continue; 493 494 if (ConsiderLinkage && 495 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 496 continue; 497 498 F.erase(); 499 } 500 501 F.done(); 502} 503 504static bool isUsingDecl(NamedDecl *D) { 505 return isa<UsingShadowDecl>(D) || 506 isa<UnresolvedUsingTypenameDecl>(D) || 507 isa<UnresolvedUsingValueDecl>(D); 508} 509 510/// Removes using shadow declarations from the lookup results. 511static void RemoveUsingDecls(LookupResult &R) { 512 LookupResult::Filter F = R.makeFilter(); 513 while (F.hasNext()) 514 if (isUsingDecl(F.next())) 515 F.erase(); 516 517 F.done(); 518} 519 520static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 521 if (D->isInvalidDecl()) 522 return false; 523 524 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 525 return false; 526 527 // White-list anything that isn't a local variable. 528 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 529 !D->getDeclContext()->isFunctionOrMethod()) 530 return false; 531 532 // Types of valid local variables should be complete, so this should succeed. 533 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 534 535 // White-list anything with an __attribute__((unused)) type. 536 QualType Ty = VD->getType(); 537 538 // Only look at the outermost level of typedef. 539 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 540 if (TT->getDecl()->hasAttr<UnusedAttr>()) 541 return false; 542 } 543 544 // If we failed to complete the type for some reason, or if the type is 545 // dependent, don't diagnose the variable. 546 if (Ty->isIncompleteType() || Ty->isDependentType()) 547 return false; 548 549 if (const TagType *TT = Ty->getAs<TagType>()) { 550 const TagDecl *Tag = TT->getDecl(); 551 if (Tag->hasAttr<UnusedAttr>()) 552 return false; 553 554 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 555 // FIXME: Checking for the presence of a user-declared constructor 556 // isn't completely accurate; we'd prefer to check that the initializer 557 // has no side effects. 558 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 559 return false; 560 } 561 } 562 563 // TODO: __attribute__((unused)) templates? 564 } 565 566 return true; 567} 568 569void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 570 if (!ShouldDiagnoseUnusedDecl(D)) 571 return; 572 573 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 574 Diag(D->getLocation(), diag::warn_unused_exception_param) 575 << D->getDeclName(); 576 else 577 Diag(D->getLocation(), diag::warn_unused_variable) 578 << D->getDeclName(); 579} 580 581void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 582 if (S->decl_empty()) return; 583 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 584 "Scope shouldn't contain decls!"); 585 586 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 587 I != E; ++I) { 588 Decl *TmpD = (*I).getAs<Decl>(); 589 assert(TmpD && "This decl didn't get pushed??"); 590 591 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 592 NamedDecl *D = cast<NamedDecl>(TmpD); 593 594 if (!D->getDeclName()) continue; 595 596 // Diagnose unused variables in this scope. 597 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 598 DiagnoseUnusedDecl(D); 599 600 // Remove this name from our lexical scope. 601 IdResolver.RemoveDecl(D); 602 } 603} 604 605/// \brief Look for an Objective-C class in the translation unit. 606/// 607/// \param Id The name of the Objective-C class we're looking for. If 608/// typo-correction fixes this name, the Id will be updated 609/// to the fixed name. 610/// 611/// \param IdLoc The location of the name in the translation unit. 612/// 613/// \param TypoCorrection If true, this routine will attempt typo correction 614/// if there is no class with the given name. 615/// 616/// \returns The declaration of the named Objective-C class, or NULL if the 617/// class could not be found. 618ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 619 SourceLocation IdLoc, 620 bool TypoCorrection) { 621 // The third "scope" argument is 0 since we aren't enabling lazy built-in 622 // creation from this context. 623 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 624 625 if (!IDecl && TypoCorrection) { 626 // Perform typo correction at the given location, but only if we 627 // find an Objective-C class name. 628 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 629 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 630 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 631 Diag(IdLoc, diag::err_undef_interface_suggest) 632 << Id << IDecl->getDeclName() 633 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 634 Diag(IDecl->getLocation(), diag::note_previous_decl) 635 << IDecl->getDeclName(); 636 637 Id = IDecl->getIdentifier(); 638 } 639 } 640 641 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 642} 643 644/// getNonFieldDeclScope - Retrieves the innermost scope, starting 645/// from S, where a non-field would be declared. This routine copes 646/// with the difference between C and C++ scoping rules in structs and 647/// unions. For example, the following code is well-formed in C but 648/// ill-formed in C++: 649/// @code 650/// struct S6 { 651/// enum { BAR } e; 652/// }; 653/// 654/// void test_S6() { 655/// struct S6 a; 656/// a.e = BAR; 657/// } 658/// @endcode 659/// For the declaration of BAR, this routine will return a different 660/// scope. The scope S will be the scope of the unnamed enumeration 661/// within S6. In C++, this routine will return the scope associated 662/// with S6, because the enumeration's scope is a transparent 663/// context but structures can contain non-field names. In C, this 664/// routine will return the translation unit scope, since the 665/// enumeration's scope is a transparent context and structures cannot 666/// contain non-field names. 667Scope *Sema::getNonFieldDeclScope(Scope *S) { 668 while (((S->getFlags() & Scope::DeclScope) == 0) || 669 (S->getEntity() && 670 ((DeclContext *)S->getEntity())->isTransparentContext()) || 671 (S->isClassScope() && !getLangOptions().CPlusPlus)) 672 S = S->getParent(); 673 return S; 674} 675 676void Sema::InitBuiltinVaListType() { 677 if (!Context.getBuiltinVaListType().isNull()) 678 return; 679 680 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 681 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 682 LookupOrdinaryName, ForRedeclaration); 683 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 684 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 685} 686 687/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 688/// file scope. lazily create a decl for it. ForRedeclaration is true 689/// if we're creating this built-in in anticipation of redeclaring the 690/// built-in. 691NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 692 Scope *S, bool ForRedeclaration, 693 SourceLocation Loc) { 694 Builtin::ID BID = (Builtin::ID)bid; 695 696 if (Context.BuiltinInfo.hasVAListUse(BID)) 697 InitBuiltinVaListType(); 698 699 ASTContext::GetBuiltinTypeError Error; 700 QualType R = Context.GetBuiltinType(BID, Error); 701 switch (Error) { 702 case ASTContext::GE_None: 703 // Okay 704 break; 705 706 case ASTContext::GE_Missing_stdio: 707 if (ForRedeclaration) 708 Diag(Loc, diag::err_implicit_decl_requires_stdio) 709 << Context.BuiltinInfo.GetName(BID); 710 return 0; 711 712 case ASTContext::GE_Missing_setjmp: 713 if (ForRedeclaration) 714 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 715 << Context.BuiltinInfo.GetName(BID); 716 return 0; 717 } 718 719 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 720 Diag(Loc, diag::ext_implicit_lib_function_decl) 721 << Context.BuiltinInfo.GetName(BID) 722 << R; 723 if (Context.BuiltinInfo.getHeaderName(BID) && 724 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 725 != Diagnostic::Ignored) 726 Diag(Loc, diag::note_please_include_header) 727 << Context.BuiltinInfo.getHeaderName(BID) 728 << Context.BuiltinInfo.GetName(BID); 729 } 730 731 FunctionDecl *New = FunctionDecl::Create(Context, 732 Context.getTranslationUnitDecl(), 733 Loc, II, R, /*TInfo=*/0, 734 FunctionDecl::Extern, 735 FunctionDecl::None, false, 736 /*hasPrototype=*/true); 737 New->setImplicit(); 738 739 // Create Decl objects for each parameter, adding them to the 740 // FunctionDecl. 741 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 742 llvm::SmallVector<ParmVarDecl*, 16> Params; 743 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 744 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 745 FT->getArgType(i), /*TInfo=*/0, 746 VarDecl::None, VarDecl::None, 0)); 747 New->setParams(Params.data(), Params.size()); 748 } 749 750 AddKnownFunctionAttributes(New); 751 752 // TUScope is the translation-unit scope to insert this function into. 753 // FIXME: This is hideous. We need to teach PushOnScopeChains to 754 // relate Scopes to DeclContexts, and probably eliminate CurContext 755 // entirely, but we're not there yet. 756 DeclContext *SavedContext = CurContext; 757 CurContext = Context.getTranslationUnitDecl(); 758 PushOnScopeChains(New, TUScope); 759 CurContext = SavedContext; 760 return New; 761} 762 763/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 764/// same name and scope as a previous declaration 'Old'. Figure out 765/// how to resolve this situation, merging decls or emitting 766/// diagnostics as appropriate. If there was an error, set New to be invalid. 767/// 768void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 769 // If the new decl is known invalid already, don't bother doing any 770 // merging checks. 771 if (New->isInvalidDecl()) return; 772 773 // Allow multiple definitions for ObjC built-in typedefs. 774 // FIXME: Verify the underlying types are equivalent! 775 if (getLangOptions().ObjC1) { 776 const IdentifierInfo *TypeID = New->getIdentifier(); 777 switch (TypeID->getLength()) { 778 default: break; 779 case 2: 780 if (!TypeID->isStr("id")) 781 break; 782 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 783 // Install the built-in type for 'id', ignoring the current definition. 784 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 785 return; 786 case 5: 787 if (!TypeID->isStr("Class")) 788 break; 789 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 790 // Install the built-in type for 'Class', ignoring the current definition. 791 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 792 return; 793 case 3: 794 if (!TypeID->isStr("SEL")) 795 break; 796 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 797 // Install the built-in type for 'SEL', ignoring the current definition. 798 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 799 return; 800 case 8: 801 if (!TypeID->isStr("Protocol")) 802 break; 803 Context.setObjCProtoType(New->getUnderlyingType()); 804 return; 805 } 806 // Fall through - the typedef name was not a builtin type. 807 } 808 809 // Verify the old decl was also a type. 810 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 811 if (!Old) { 812 Diag(New->getLocation(), diag::err_redefinition_different_kind) 813 << New->getDeclName(); 814 815 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 816 if (OldD->getLocation().isValid()) 817 Diag(OldD->getLocation(), diag::note_previous_definition); 818 819 return New->setInvalidDecl(); 820 } 821 822 // If the old declaration is invalid, just give up here. 823 if (Old->isInvalidDecl()) 824 return New->setInvalidDecl(); 825 826 // Determine the "old" type we'll use for checking and diagnostics. 827 QualType OldType; 828 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 829 OldType = OldTypedef->getUnderlyingType(); 830 else 831 OldType = Context.getTypeDeclType(Old); 832 833 // If the typedef types are not identical, reject them in all languages and 834 // with any extensions enabled. 835 836 if (OldType != New->getUnderlyingType() && 837 Context.getCanonicalType(OldType) != 838 Context.getCanonicalType(New->getUnderlyingType())) { 839 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 840 << New->getUnderlyingType() << OldType; 841 if (Old->getLocation().isValid()) 842 Diag(Old->getLocation(), diag::note_previous_definition); 843 return New->setInvalidDecl(); 844 } 845 846 // The types match. Link up the redeclaration chain if the old 847 // declaration was a typedef. 848 // FIXME: this is a potential source of wierdness if the type 849 // spellings don't match exactly. 850 if (isa<TypedefDecl>(Old)) 851 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 852 853 if (getLangOptions().Microsoft) 854 return; 855 856 if (getLangOptions().CPlusPlus) { 857 // C++ [dcl.typedef]p2: 858 // In a given non-class scope, a typedef specifier can be used to 859 // redefine the name of any type declared in that scope to refer 860 // to the type to which it already refers. 861 if (!isa<CXXRecordDecl>(CurContext)) 862 return; 863 864 // C++0x [dcl.typedef]p4: 865 // In a given class scope, a typedef specifier can be used to redefine 866 // any class-name declared in that scope that is not also a typedef-name 867 // to refer to the type to which it already refers. 868 // 869 // This wording came in via DR424, which was a correction to the 870 // wording in DR56, which accidentally banned code like: 871 // 872 // struct S { 873 // typedef struct A { } A; 874 // }; 875 // 876 // in the C++03 standard. We implement the C++0x semantics, which 877 // allow the above but disallow 878 // 879 // struct S { 880 // typedef int I; 881 // typedef int I; 882 // }; 883 // 884 // since that was the intent of DR56. 885 if (!isa<TypedefDecl >(Old)) 886 return; 887 888 Diag(New->getLocation(), diag::err_redefinition) 889 << New->getDeclName(); 890 Diag(Old->getLocation(), diag::note_previous_definition); 891 return New->setInvalidDecl(); 892 } 893 894 // If we have a redefinition of a typedef in C, emit a warning. This warning 895 // is normally mapped to an error, but can be controlled with 896 // -Wtypedef-redefinition. If either the original or the redefinition is 897 // in a system header, don't emit this for compatibility with GCC. 898 if (getDiagnostics().getSuppressSystemWarnings() && 899 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 900 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 901 return; 902 903 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 904 << New->getDeclName(); 905 Diag(Old->getLocation(), diag::note_previous_definition); 906 return; 907} 908 909/// DeclhasAttr - returns true if decl Declaration already has the target 910/// attribute. 911static bool 912DeclHasAttr(const Decl *decl, const Attr *target) { 913 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 914 if (attr->getKind() == target->getKind()) 915 return true; 916 917 return false; 918} 919 920/// MergeAttributes - append attributes from the Old decl to the New one. 921static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 922 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 923 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 924 Attr *NewAttr = attr->clone(C); 925 NewAttr->setInherited(true); 926 New->addAttr(NewAttr); 927 } 928 } 929} 930 931/// Used in MergeFunctionDecl to keep track of function parameters in 932/// C. 933struct GNUCompatibleParamWarning { 934 ParmVarDecl *OldParm; 935 ParmVarDecl *NewParm; 936 QualType PromotedType; 937}; 938 939 940/// getSpecialMember - get the special member enum for a method. 941Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 942 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 943 if (Ctor->isCopyConstructor()) 944 return Sema::CXXCopyConstructor; 945 946 return Sema::CXXConstructor; 947 } 948 949 if (isa<CXXDestructorDecl>(MD)) 950 return Sema::CXXDestructor; 951 952 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 953 return Sema::CXXCopyAssignment; 954} 955 956/// canRedefineFunction - checks if a function can be redefined. Currently, 957/// only extern inline functions can be redefined, and even then only in 958/// GNU89 mode. 959static bool canRedefineFunction(const FunctionDecl *FD, 960 const LangOptions& LangOpts) { 961 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 962 FD->isInlineSpecified() && 963 FD->getStorageClass() == FunctionDecl::Extern); 964} 965 966/// MergeFunctionDecl - We just parsed a function 'New' from 967/// declarator D which has the same name and scope as a previous 968/// declaration 'Old'. Figure out how to resolve this situation, 969/// merging decls or emitting diagnostics as appropriate. 970/// 971/// In C++, New and Old must be declarations that are not 972/// overloaded. Use IsOverload to determine whether New and Old are 973/// overloaded, and to select the Old declaration that New should be 974/// merged with. 975/// 976/// Returns true if there was an error, false otherwise. 977bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 978 // Verify the old decl was also a function. 979 FunctionDecl *Old = 0; 980 if (FunctionTemplateDecl *OldFunctionTemplate 981 = dyn_cast<FunctionTemplateDecl>(OldD)) 982 Old = OldFunctionTemplate->getTemplatedDecl(); 983 else 984 Old = dyn_cast<FunctionDecl>(OldD); 985 if (!Old) { 986 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 987 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 988 Diag(Shadow->getTargetDecl()->getLocation(), 989 diag::note_using_decl_target); 990 Diag(Shadow->getUsingDecl()->getLocation(), 991 diag::note_using_decl) << 0; 992 return true; 993 } 994 995 Diag(New->getLocation(), diag::err_redefinition_different_kind) 996 << New->getDeclName(); 997 Diag(OldD->getLocation(), diag::note_previous_definition); 998 return true; 999 } 1000 1001 // Determine whether the previous declaration was a definition, 1002 // implicit declaration, or a declaration. 1003 diag::kind PrevDiag; 1004 if (Old->isThisDeclarationADefinition()) 1005 PrevDiag = diag::note_previous_definition; 1006 else if (Old->isImplicit()) 1007 PrevDiag = diag::note_previous_implicit_declaration; 1008 else 1009 PrevDiag = diag::note_previous_declaration; 1010 1011 QualType OldQType = Context.getCanonicalType(Old->getType()); 1012 QualType NewQType = Context.getCanonicalType(New->getType()); 1013 1014 // Don't complain about this if we're in GNU89 mode and the old function 1015 // is an extern inline function. 1016 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1017 New->getStorageClass() == FunctionDecl::Static && 1018 Old->getStorageClass() != FunctionDecl::Static && 1019 !canRedefineFunction(Old, getLangOptions())) { 1020 Diag(New->getLocation(), diag::err_static_non_static) 1021 << New; 1022 Diag(Old->getLocation(), PrevDiag); 1023 return true; 1024 } 1025 1026 // If a function is first declared with a calling convention, but is 1027 // later declared or defined without one, the second decl assumes the 1028 // calling convention of the first. 1029 // 1030 // For the new decl, we have to look at the NON-canonical type to tell the 1031 // difference between a function that really doesn't have a calling 1032 // convention and one that is declared cdecl. That's because in 1033 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1034 // because it is the default calling convention. 1035 // 1036 // Note also that we DO NOT return at this point, because we still have 1037 // other tests to run. 1038 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1039 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1040 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1041 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1042 if (OldTypeInfo.getCC() != CC_Default && 1043 NewTypeInfo.getCC() == CC_Default) { 1044 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1045 New->setType(NewQType); 1046 NewQType = Context.getCanonicalType(NewQType); 1047 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1048 NewTypeInfo.getCC())) { 1049 // Calling conventions really aren't compatible, so complain. 1050 Diag(New->getLocation(), diag::err_cconv_change) 1051 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1052 << (OldTypeInfo.getCC() == CC_Default) 1053 << (OldTypeInfo.getCC() == CC_Default ? "" : 1054 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1055 Diag(Old->getLocation(), diag::note_previous_declaration); 1056 return true; 1057 } 1058 1059 // FIXME: diagnose the other way around? 1060 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1061 NewQType = Context.getNoReturnType(NewQType); 1062 New->setType(NewQType); 1063 assert(NewQType.isCanonical()); 1064 } 1065 1066 // Merge regparm attribute. 1067 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1068 if (NewType->getRegParmType()) { 1069 Diag(New->getLocation(), diag::err_regparm_mismatch) 1070 << NewType->getRegParmType() 1071 << OldType->getRegParmType(); 1072 Diag(Old->getLocation(), diag::note_previous_declaration); 1073 return true; 1074 } 1075 1076 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1077 New->setType(NewQType); 1078 assert(NewQType.isCanonical()); 1079 } 1080 1081 if (getLangOptions().CPlusPlus) { 1082 // (C++98 13.1p2): 1083 // Certain function declarations cannot be overloaded: 1084 // -- Function declarations that differ only in the return type 1085 // cannot be overloaded. 1086 QualType OldReturnType 1087 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1088 QualType NewReturnType 1089 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1090 QualType ResQT; 1091 if (OldReturnType != NewReturnType) { 1092 if (NewReturnType->isObjCObjectPointerType() 1093 && OldReturnType->isObjCObjectPointerType()) 1094 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1095 if (ResQT.isNull()) { 1096 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1097 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1098 return true; 1099 } 1100 else 1101 NewQType = ResQT; 1102 } 1103 1104 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1105 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1106 if (OldMethod && NewMethod) { 1107 // Preserve triviality. 1108 NewMethod->setTrivial(OldMethod->isTrivial()); 1109 1110 bool isFriend = NewMethod->getFriendObjectKind(); 1111 1112 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1113 // -- Member function declarations with the same name and the 1114 // same parameter types cannot be overloaded if any of them 1115 // is a static member function declaration. 1116 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1117 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1118 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1119 return true; 1120 } 1121 1122 // C++ [class.mem]p1: 1123 // [...] A member shall not be declared twice in the 1124 // member-specification, except that a nested class or member 1125 // class template can be declared and then later defined. 1126 unsigned NewDiag; 1127 if (isa<CXXConstructorDecl>(OldMethod)) 1128 NewDiag = diag::err_constructor_redeclared; 1129 else if (isa<CXXDestructorDecl>(NewMethod)) 1130 NewDiag = diag::err_destructor_redeclared; 1131 else if (isa<CXXConversionDecl>(NewMethod)) 1132 NewDiag = diag::err_conv_function_redeclared; 1133 else 1134 NewDiag = diag::err_member_redeclared; 1135 1136 Diag(New->getLocation(), NewDiag); 1137 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1138 1139 // Complain if this is an explicit declaration of a special 1140 // member that was initially declared implicitly. 1141 // 1142 // As an exception, it's okay to befriend such methods in order 1143 // to permit the implicit constructor/destructor/operator calls. 1144 } else if (OldMethod->isImplicit()) { 1145 if (isFriend) { 1146 NewMethod->setImplicit(); 1147 } else { 1148 Diag(NewMethod->getLocation(), 1149 diag::err_definition_of_implicitly_declared_member) 1150 << New << getSpecialMember(OldMethod); 1151 return true; 1152 } 1153 } 1154 } 1155 1156 // (C++98 8.3.5p3): 1157 // All declarations for a function shall agree exactly in both the 1158 // return type and the parameter-type-list. 1159 // attributes should be ignored when comparing. 1160 if (Context.getNoReturnType(OldQType, false) == 1161 Context.getNoReturnType(NewQType, false)) 1162 return MergeCompatibleFunctionDecls(New, Old); 1163 1164 // Fall through for conflicting redeclarations and redefinitions. 1165 } 1166 1167 // C: Function types need to be compatible, not identical. This handles 1168 // duplicate function decls like "void f(int); void f(enum X);" properly. 1169 if (!getLangOptions().CPlusPlus && 1170 Context.typesAreCompatible(OldQType, NewQType)) { 1171 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1172 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1173 const FunctionProtoType *OldProto = 0; 1174 if (isa<FunctionNoProtoType>(NewFuncType) && 1175 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1176 // The old declaration provided a function prototype, but the 1177 // new declaration does not. Merge in the prototype. 1178 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1179 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1180 OldProto->arg_type_end()); 1181 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1182 ParamTypes.data(), ParamTypes.size(), 1183 OldProto->isVariadic(), 1184 OldProto->getTypeQuals(), 1185 false, false, 0, 0, 1186 OldProto->getExtInfo()); 1187 New->setType(NewQType); 1188 New->setHasInheritedPrototype(); 1189 1190 // Synthesize a parameter for each argument type. 1191 llvm::SmallVector<ParmVarDecl*, 16> Params; 1192 for (FunctionProtoType::arg_type_iterator 1193 ParamType = OldProto->arg_type_begin(), 1194 ParamEnd = OldProto->arg_type_end(); 1195 ParamType != ParamEnd; ++ParamType) { 1196 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1197 SourceLocation(), 0, 1198 *ParamType, /*TInfo=*/0, 1199 VarDecl::None, VarDecl::None, 1200 0); 1201 Param->setImplicit(); 1202 Params.push_back(Param); 1203 } 1204 1205 New->setParams(Params.data(), Params.size()); 1206 } 1207 1208 return MergeCompatibleFunctionDecls(New, Old); 1209 } 1210 1211 // GNU C permits a K&R definition to follow a prototype declaration 1212 // if the declared types of the parameters in the K&R definition 1213 // match the types in the prototype declaration, even when the 1214 // promoted types of the parameters from the K&R definition differ 1215 // from the types in the prototype. GCC then keeps the types from 1216 // the prototype. 1217 // 1218 // If a variadic prototype is followed by a non-variadic K&R definition, 1219 // the K&R definition becomes variadic. This is sort of an edge case, but 1220 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1221 // C99 6.9.1p8. 1222 if (!getLangOptions().CPlusPlus && 1223 Old->hasPrototype() && !New->hasPrototype() && 1224 New->getType()->getAs<FunctionProtoType>() && 1225 Old->getNumParams() == New->getNumParams()) { 1226 llvm::SmallVector<QualType, 16> ArgTypes; 1227 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1228 const FunctionProtoType *OldProto 1229 = Old->getType()->getAs<FunctionProtoType>(); 1230 const FunctionProtoType *NewProto 1231 = New->getType()->getAs<FunctionProtoType>(); 1232 1233 // Determine whether this is the GNU C extension. 1234 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1235 NewProto->getResultType()); 1236 bool LooseCompatible = !MergedReturn.isNull(); 1237 for (unsigned Idx = 0, End = Old->getNumParams(); 1238 LooseCompatible && Idx != End; ++Idx) { 1239 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1240 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1241 if (Context.typesAreCompatible(OldParm->getType(), 1242 NewProto->getArgType(Idx))) { 1243 ArgTypes.push_back(NewParm->getType()); 1244 } else if (Context.typesAreCompatible(OldParm->getType(), 1245 NewParm->getType())) { 1246 GNUCompatibleParamWarning Warn 1247 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1248 Warnings.push_back(Warn); 1249 ArgTypes.push_back(NewParm->getType()); 1250 } else 1251 LooseCompatible = false; 1252 } 1253 1254 if (LooseCompatible) { 1255 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1256 Diag(Warnings[Warn].NewParm->getLocation(), 1257 diag::ext_param_promoted_not_compatible_with_prototype) 1258 << Warnings[Warn].PromotedType 1259 << Warnings[Warn].OldParm->getType(); 1260 Diag(Warnings[Warn].OldParm->getLocation(), 1261 diag::note_previous_declaration); 1262 } 1263 1264 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1265 ArgTypes.size(), 1266 OldProto->isVariadic(), 0, 1267 false, false, 0, 0, 1268 OldProto->getExtInfo())); 1269 return MergeCompatibleFunctionDecls(New, Old); 1270 } 1271 1272 // Fall through to diagnose conflicting types. 1273 } 1274 1275 // A function that has already been declared has been redeclared or defined 1276 // with a different type- show appropriate diagnostic 1277 if (unsigned BuiltinID = Old->getBuiltinID()) { 1278 // The user has declared a builtin function with an incompatible 1279 // signature. 1280 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1281 // The function the user is redeclaring is a library-defined 1282 // function like 'malloc' or 'printf'. Warn about the 1283 // redeclaration, then pretend that we don't know about this 1284 // library built-in. 1285 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1286 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1287 << Old << Old->getType(); 1288 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1289 Old->setInvalidDecl(); 1290 return false; 1291 } 1292 1293 PrevDiag = diag::note_previous_builtin_declaration; 1294 } 1295 1296 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1297 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1298 return true; 1299} 1300 1301/// \brief Completes the merge of two function declarations that are 1302/// known to be compatible. 1303/// 1304/// This routine handles the merging of attributes and other 1305/// properties of function declarations form the old declaration to 1306/// the new declaration, once we know that New is in fact a 1307/// redeclaration of Old. 1308/// 1309/// \returns false 1310bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1311 // Merge the attributes 1312 MergeAttributes(New, Old, Context); 1313 1314 // Merge the storage class. 1315 if (Old->getStorageClass() != FunctionDecl::Extern && 1316 Old->getStorageClass() != FunctionDecl::None) 1317 New->setStorageClass(Old->getStorageClass()); 1318 1319 // Merge "pure" flag. 1320 if (Old->isPure()) 1321 New->setPure(); 1322 1323 // Merge the "deleted" flag. 1324 if (Old->isDeleted()) 1325 New->setDeleted(); 1326 1327 if (getLangOptions().CPlusPlus) 1328 return MergeCXXFunctionDecl(New, Old); 1329 1330 return false; 1331} 1332 1333/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1334/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1335/// situation, merging decls or emitting diagnostics as appropriate. 1336/// 1337/// Tentative definition rules (C99 6.9.2p2) are checked by 1338/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1339/// definitions here, since the initializer hasn't been attached. 1340/// 1341void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1342 // If the new decl is already invalid, don't do any other checking. 1343 if (New->isInvalidDecl()) 1344 return; 1345 1346 // Verify the old decl was also a variable. 1347 VarDecl *Old = 0; 1348 if (!Previous.isSingleResult() || 1349 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1350 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1351 << New->getDeclName(); 1352 Diag(Previous.getRepresentativeDecl()->getLocation(), 1353 diag::note_previous_definition); 1354 return New->setInvalidDecl(); 1355 } 1356 1357 MergeAttributes(New, Old, Context); 1358 1359 // Merge the types 1360 QualType MergedT; 1361 if (getLangOptions().CPlusPlus) { 1362 if (Context.hasSameType(New->getType(), Old->getType())) 1363 MergedT = New->getType(); 1364 // C++ [basic.link]p10: 1365 // [...] the types specified by all declarations referring to a given 1366 // object or function shall be identical, except that declarations for an 1367 // array object can specify array types that differ by the presence or 1368 // absence of a major array bound (8.3.4). 1369 else if (Old->getType()->isIncompleteArrayType() && 1370 New->getType()->isArrayType()) { 1371 CanQual<ArrayType> OldArray 1372 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1373 CanQual<ArrayType> NewArray 1374 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1375 if (OldArray->getElementType() == NewArray->getElementType()) 1376 MergedT = New->getType(); 1377 } else if (Old->getType()->isArrayType() && 1378 New->getType()->isIncompleteArrayType()) { 1379 CanQual<ArrayType> OldArray 1380 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1381 CanQual<ArrayType> NewArray 1382 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1383 if (OldArray->getElementType() == NewArray->getElementType()) 1384 MergedT = Old->getType(); 1385 } else if (New->getType()->isObjCObjectPointerType() 1386 && Old->getType()->isObjCObjectPointerType()) { 1387 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1388 } 1389 } else { 1390 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1391 } 1392 if (MergedT.isNull()) { 1393 Diag(New->getLocation(), diag::err_redefinition_different_type) 1394 << New->getDeclName(); 1395 Diag(Old->getLocation(), diag::note_previous_definition); 1396 return New->setInvalidDecl(); 1397 } 1398 New->setType(MergedT); 1399 1400 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1401 if (New->getStorageClass() == VarDecl::Static && 1402 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1403 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1404 Diag(Old->getLocation(), diag::note_previous_definition); 1405 return New->setInvalidDecl(); 1406 } 1407 // C99 6.2.2p4: 1408 // For an identifier declared with the storage-class specifier 1409 // extern in a scope in which a prior declaration of that 1410 // identifier is visible,23) if the prior declaration specifies 1411 // internal or external linkage, the linkage of the identifier at 1412 // the later declaration is the same as the linkage specified at 1413 // the prior declaration. If no prior declaration is visible, or 1414 // if the prior declaration specifies no linkage, then the 1415 // identifier has external linkage. 1416 if (New->hasExternalStorage() && Old->hasLinkage()) 1417 /* Okay */; 1418 else if (New->getStorageClass() != VarDecl::Static && 1419 Old->getStorageClass() == VarDecl::Static) { 1420 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1421 Diag(Old->getLocation(), diag::note_previous_definition); 1422 return New->setInvalidDecl(); 1423 } 1424 1425 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1426 1427 // FIXME: The test for external storage here seems wrong? We still 1428 // need to check for mismatches. 1429 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1430 // Don't complain about out-of-line definitions of static members. 1431 !(Old->getLexicalDeclContext()->isRecord() && 1432 !New->getLexicalDeclContext()->isRecord())) { 1433 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1434 Diag(Old->getLocation(), diag::note_previous_definition); 1435 return New->setInvalidDecl(); 1436 } 1437 1438 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1439 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1440 Diag(Old->getLocation(), diag::note_previous_definition); 1441 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1442 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1443 Diag(Old->getLocation(), diag::note_previous_definition); 1444 } 1445 1446 // C++ doesn't have tentative definitions, so go right ahead and check here. 1447 const VarDecl *Def; 1448 if (getLangOptions().CPlusPlus && 1449 New->isThisDeclarationADefinition() == VarDecl::Definition && 1450 (Def = Old->getDefinition())) { 1451 Diag(New->getLocation(), diag::err_redefinition) 1452 << New->getDeclName(); 1453 Diag(Def->getLocation(), diag::note_previous_definition); 1454 New->setInvalidDecl(); 1455 return; 1456 } 1457 1458 if (New->hasExternalStorage() && 1459 Old->getLinkage() == InternalLinkage && 1460 New->getDeclContext() == Old->getDeclContext()) 1461 New->setStorageClass(Old->getStorageClass()); 1462 1463 // Keep a chain of previous declarations. 1464 New->setPreviousDeclaration(Old); 1465 1466 // Inherit access appropriately. 1467 New->setAccess(Old->getAccess()); 1468} 1469 1470/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1471/// no declarator (e.g. "struct foo;") is parsed. 1472Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1473 DeclSpec &DS) { 1474 // FIXME: Error on auto/register at file scope 1475 // FIXME: Error on inline/virtual/explicit 1476 // FIXME: Warn on useless __thread 1477 // FIXME: Warn on useless const/volatile 1478 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1479 // FIXME: Warn on useless attributes 1480 Decl *TagD = 0; 1481 TagDecl *Tag = 0; 1482 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1483 DS.getTypeSpecType() == DeclSpec::TST_struct || 1484 DS.getTypeSpecType() == DeclSpec::TST_union || 1485 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1486 TagD = static_cast<Decl *>(DS.getTypeRep()); 1487 1488 if (!TagD) // We probably had an error 1489 return DeclPtrTy(); 1490 1491 // Note that the above type specs guarantee that the 1492 // type rep is a Decl, whereas in many of the others 1493 // it's a Type. 1494 Tag = dyn_cast<TagDecl>(TagD); 1495 } 1496 1497 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1498 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1499 // or incomplete types shall not be restrict-qualified." 1500 if (TypeQuals & DeclSpec::TQ_restrict) 1501 Diag(DS.getRestrictSpecLoc(), 1502 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1503 << DS.getSourceRange(); 1504 } 1505 1506 if (DS.isFriendSpecified()) { 1507 // If we're dealing with a class template decl, assume that the 1508 // template routines are handling it. 1509 if (TagD && isa<ClassTemplateDecl>(TagD)) 1510 return DeclPtrTy(); 1511 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1512 } 1513 1514 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1515 // If there are attributes in the DeclSpec, apply them to the record. 1516 if (const AttributeList *AL = DS.getAttributes()) 1517 ProcessDeclAttributeList(S, Record, AL); 1518 1519 if (!Record->getDeclName() && Record->isDefinition() && 1520 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1521 if (getLangOptions().CPlusPlus || 1522 Record->getDeclContext()->isRecord()) 1523 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1524 1525 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1526 << DS.getSourceRange(); 1527 } 1528 1529 // Microsoft allows unnamed struct/union fields. Don't complain 1530 // about them. 1531 // FIXME: Should we support Microsoft's extensions in this area? 1532 if (Record->getDeclName() && getLangOptions().Microsoft) 1533 return DeclPtrTy::make(Tag); 1534 } 1535 1536 if (!DS.isMissingDeclaratorOk() && 1537 DS.getTypeSpecType() != DeclSpec::TST_error) { 1538 // Warn about typedefs of enums without names, since this is an 1539 // extension in both Microsoft an GNU. 1540 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1541 Tag && isa<EnumDecl>(Tag)) { 1542 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1543 << DS.getSourceRange(); 1544 return DeclPtrTy::make(Tag); 1545 } 1546 1547 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1548 << DS.getSourceRange(); 1549 } 1550 1551 return DeclPtrTy::make(Tag); 1552} 1553 1554/// We are trying to inject an anonymous member into the given scope; 1555/// check if there's an existing declaration that can't be overloaded. 1556/// 1557/// \return true if this is a forbidden redeclaration 1558static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1559 Scope *S, 1560 DeclContext *Owner, 1561 DeclarationName Name, 1562 SourceLocation NameLoc, 1563 unsigned diagnostic) { 1564 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1565 Sema::ForRedeclaration); 1566 if (!SemaRef.LookupName(R, S)) return false; 1567 1568 if (R.getAsSingle<TagDecl>()) 1569 return false; 1570 1571 // Pick a representative declaration. 1572 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1573 if (PrevDecl && Owner->isRecord()) { 1574 RecordDecl *Record = cast<RecordDecl>(Owner); 1575 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1576 return false; 1577 } 1578 1579 SemaRef.Diag(NameLoc, diagnostic) << Name; 1580 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1581 1582 return true; 1583} 1584 1585/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1586/// anonymous struct or union AnonRecord into the owning context Owner 1587/// and scope S. This routine will be invoked just after we realize 1588/// that an unnamed union or struct is actually an anonymous union or 1589/// struct, e.g., 1590/// 1591/// @code 1592/// union { 1593/// int i; 1594/// float f; 1595/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1596/// // f into the surrounding scope.x 1597/// @endcode 1598/// 1599/// This routine is recursive, injecting the names of nested anonymous 1600/// structs/unions into the owning context and scope as well. 1601static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1602 DeclContext *Owner, 1603 RecordDecl *AnonRecord, 1604 AccessSpecifier AS) { 1605 unsigned diagKind 1606 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1607 : diag::err_anonymous_struct_member_redecl; 1608 1609 bool Invalid = false; 1610 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1611 FEnd = AnonRecord->field_end(); 1612 F != FEnd; ++F) { 1613 if ((*F)->getDeclName()) { 1614 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1615 (*F)->getLocation(), diagKind)) { 1616 // C++ [class.union]p2: 1617 // The names of the members of an anonymous union shall be 1618 // distinct from the names of any other entity in the 1619 // scope in which the anonymous union is declared. 1620 Invalid = true; 1621 } else { 1622 // C++ [class.union]p2: 1623 // For the purpose of name lookup, after the anonymous union 1624 // definition, the members of the anonymous union are 1625 // considered to have been defined in the scope in which the 1626 // anonymous union is declared. 1627 Owner->makeDeclVisibleInContext(*F); 1628 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1629 SemaRef.IdResolver.AddDecl(*F); 1630 1631 // That includes picking up the appropriate access specifier. 1632 if (AS != AS_none) (*F)->setAccess(AS); 1633 } 1634 } else if (const RecordType *InnerRecordType 1635 = (*F)->getType()->getAs<RecordType>()) { 1636 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1637 if (InnerRecord->isAnonymousStructOrUnion()) 1638 Invalid = Invalid || 1639 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1640 InnerRecord, AS); 1641 } 1642 } 1643 1644 return Invalid; 1645} 1646 1647/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1648/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1649/// illegal input values are mapped to VarDecl::None. 1650/// If the input declaration context is a linkage specification 1651/// with no braces, then Extern is mapped to None. 1652static VarDecl::StorageClass 1653StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1654 DeclContext *DC) { 1655 switch (StorageClassSpec) { 1656 case DeclSpec::SCS_unspecified: return VarDecl::None; 1657 case DeclSpec::SCS_extern: 1658 // If the current context is a C++ linkage specification 1659 // having no braces, then the keyword "extern" is properly part 1660 // of the linkage specification itself, rather than being 1661 // the written storage class specifier. 1662 return (DC && isa<LinkageSpecDecl>(DC) && 1663 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1664 ? VarDecl::None : VarDecl::Extern; 1665 case DeclSpec::SCS_static: return VarDecl::Static; 1666 case DeclSpec::SCS_auto: return VarDecl::Auto; 1667 case DeclSpec::SCS_register: return VarDecl::Register; 1668 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1669 // Illegal SCSs map to None: error reporting is up to the caller. 1670 case DeclSpec::SCS_mutable: // Fall through. 1671 case DeclSpec::SCS_typedef: return VarDecl::None; 1672 } 1673 llvm_unreachable("unknown storage class specifier"); 1674} 1675 1676/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1677/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1678/// illegal input values are mapped to FunctionDecl::None. 1679/// If the input declaration context is a linkage specification 1680/// with no braces, then Extern is mapped to None. 1681static FunctionDecl::StorageClass 1682StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1683 DeclContext *DC) { 1684 switch (StorageClassSpec) { 1685 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1686 case DeclSpec::SCS_extern: 1687 // If the current context is a C++ linkage specification 1688 // having no braces, then the keyword "extern" is properly part 1689 // of the linkage specification itself, rather than being 1690 // the written storage class specifier. 1691 return (DC && isa<LinkageSpecDecl>(DC) && 1692 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1693 ? FunctionDecl::None : FunctionDecl::Extern; 1694 case DeclSpec::SCS_static: return FunctionDecl::Static; 1695 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1696 // Illegal SCSs map to None: error reporting is up to the caller. 1697 case DeclSpec::SCS_auto: // Fall through. 1698 case DeclSpec::SCS_mutable: // Fall through. 1699 case DeclSpec::SCS_register: // Fall through. 1700 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1701 } 1702 llvm_unreachable("unknown storage class specifier"); 1703} 1704 1705/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1706/// anonymous structure or union. Anonymous unions are a C++ feature 1707/// (C++ [class.union]) and a GNU C extension; anonymous structures 1708/// are a GNU C and GNU C++ extension. 1709Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1710 AccessSpecifier AS, 1711 RecordDecl *Record) { 1712 DeclContext *Owner = Record->getDeclContext(); 1713 1714 // Diagnose whether this anonymous struct/union is an extension. 1715 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1716 Diag(Record->getLocation(), diag::ext_anonymous_union); 1717 else if (!Record->isUnion()) 1718 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1719 1720 // C and C++ require different kinds of checks for anonymous 1721 // structs/unions. 1722 bool Invalid = false; 1723 if (getLangOptions().CPlusPlus) { 1724 const char* PrevSpec = 0; 1725 unsigned DiagID; 1726 // C++ [class.union]p3: 1727 // Anonymous unions declared in a named namespace or in the 1728 // global namespace shall be declared static. 1729 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1730 (isa<TranslationUnitDecl>(Owner) || 1731 (isa<NamespaceDecl>(Owner) && 1732 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1733 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1734 Invalid = true; 1735 1736 // Recover by adding 'static'. 1737 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1738 PrevSpec, DiagID); 1739 } 1740 // C++ [class.union]p3: 1741 // A storage class is not allowed in a declaration of an 1742 // anonymous union in a class scope. 1743 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1744 isa<RecordDecl>(Owner)) { 1745 Diag(DS.getStorageClassSpecLoc(), 1746 diag::err_anonymous_union_with_storage_spec); 1747 Invalid = true; 1748 1749 // Recover by removing the storage specifier. 1750 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1751 PrevSpec, DiagID); 1752 } 1753 1754 // C++ [class.union]p2: 1755 // The member-specification of an anonymous union shall only 1756 // define non-static data members. [Note: nested types and 1757 // functions cannot be declared within an anonymous union. ] 1758 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1759 MemEnd = Record->decls_end(); 1760 Mem != MemEnd; ++Mem) { 1761 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1762 // C++ [class.union]p3: 1763 // An anonymous union shall not have private or protected 1764 // members (clause 11). 1765 assert(FD->getAccess() != AS_none); 1766 if (FD->getAccess() != AS_public) { 1767 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1768 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1769 Invalid = true; 1770 } 1771 } else if ((*Mem)->isImplicit()) { 1772 // Any implicit members are fine. 1773 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1774 // This is a type that showed up in an 1775 // elaborated-type-specifier inside the anonymous struct or 1776 // union, but which actually declares a type outside of the 1777 // anonymous struct or union. It's okay. 1778 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1779 if (!MemRecord->isAnonymousStructOrUnion() && 1780 MemRecord->getDeclName()) { 1781 // This is a nested type declaration. 1782 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1783 << (int)Record->isUnion(); 1784 Invalid = true; 1785 } 1786 } else if (isa<AccessSpecDecl>(*Mem)) { 1787 // Any access specifier is fine. 1788 } else { 1789 // We have something that isn't a non-static data 1790 // member. Complain about it. 1791 unsigned DK = diag::err_anonymous_record_bad_member; 1792 if (isa<TypeDecl>(*Mem)) 1793 DK = diag::err_anonymous_record_with_type; 1794 else if (isa<FunctionDecl>(*Mem)) 1795 DK = diag::err_anonymous_record_with_function; 1796 else if (isa<VarDecl>(*Mem)) 1797 DK = diag::err_anonymous_record_with_static; 1798 Diag((*Mem)->getLocation(), DK) 1799 << (int)Record->isUnion(); 1800 Invalid = true; 1801 } 1802 } 1803 } 1804 1805 if (!Record->isUnion() && !Owner->isRecord()) { 1806 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1807 << (int)getLangOptions().CPlusPlus; 1808 Invalid = true; 1809 } 1810 1811 // Mock up a declarator. 1812 Declarator Dc(DS, Declarator::TypeNameContext); 1813 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1814 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1815 1816 // Create a declaration for this anonymous struct/union. 1817 NamedDecl *Anon = 0; 1818 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1819 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1820 /*IdentifierInfo=*/0, 1821 Context.getTypeDeclType(Record), 1822 TInfo, 1823 /*BitWidth=*/0, /*Mutable=*/false); 1824 Anon->setAccess(AS); 1825 if (getLangOptions().CPlusPlus) { 1826 FieldCollector->Add(cast<FieldDecl>(Anon)); 1827 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1828 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1829 } 1830 } else { 1831 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1832 assert(SCSpec != DeclSpec::SCS_typedef && 1833 "Parser allowed 'typedef' as storage class VarDecl."); 1834 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1835 if (SCSpec == DeclSpec::SCS_mutable) { 1836 // mutable can only appear on non-static class members, so it's always 1837 // an error here 1838 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1839 Invalid = true; 1840 SC = VarDecl::None; 1841 } 1842 SCSpec = DS.getStorageClassSpecAsWritten(); 1843 VarDecl::StorageClass SCAsWritten 1844 = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1845 1846 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1847 /*IdentifierInfo=*/0, 1848 Context.getTypeDeclType(Record), 1849 TInfo, SC, SCAsWritten); 1850 } 1851 Anon->setImplicit(); 1852 1853 // Add the anonymous struct/union object to the current 1854 // context. We'll be referencing this object when we refer to one of 1855 // its members. 1856 Owner->addDecl(Anon); 1857 1858 // Inject the members of the anonymous struct/union into the owning 1859 // context and into the identifier resolver chain for name lookup 1860 // purposes. 1861 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1862 Invalid = true; 1863 1864 // Mark this as an anonymous struct/union type. Note that we do not 1865 // do this until after we have already checked and injected the 1866 // members of this anonymous struct/union type, because otherwise 1867 // the members could be injected twice: once by DeclContext when it 1868 // builds its lookup table, and once by 1869 // InjectAnonymousStructOrUnionMembers. 1870 Record->setAnonymousStructOrUnion(true); 1871 1872 if (Invalid) 1873 Anon->setInvalidDecl(); 1874 1875 return DeclPtrTy::make(Anon); 1876} 1877 1878 1879/// GetNameForDeclarator - Determine the full declaration name for the 1880/// given Declarator. 1881DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1882 return GetNameFromUnqualifiedId(D.getName()); 1883} 1884 1885/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1886DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1887 switch (Name.getKind()) { 1888 case UnqualifiedId::IK_Identifier: 1889 return DeclarationName(Name.Identifier); 1890 1891 case UnqualifiedId::IK_OperatorFunctionId: 1892 return Context.DeclarationNames.getCXXOperatorName( 1893 Name.OperatorFunctionId.Operator); 1894 1895 case UnqualifiedId::IK_LiteralOperatorId: 1896 return Context.DeclarationNames.getCXXLiteralOperatorName( 1897 Name.Identifier); 1898 1899 case UnqualifiedId::IK_ConversionFunctionId: { 1900 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1901 if (Ty.isNull()) 1902 return DeclarationName(); 1903 1904 return Context.DeclarationNames.getCXXConversionFunctionName( 1905 Context.getCanonicalType(Ty)); 1906 } 1907 1908 case UnqualifiedId::IK_ConstructorName: { 1909 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1910 if (Ty.isNull()) 1911 return DeclarationName(); 1912 1913 return Context.DeclarationNames.getCXXConstructorName( 1914 Context.getCanonicalType(Ty)); 1915 } 1916 1917 case UnqualifiedId::IK_ConstructorTemplateId: { 1918 // In well-formed code, we can only have a constructor 1919 // template-id that refers to the current context, so go there 1920 // to find the actual type being constructed. 1921 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1922 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1923 return DeclarationName(); 1924 1925 // Determine the type of the class being constructed. 1926 QualType CurClassType = Context.getTypeDeclType(CurClass); 1927 1928 // FIXME: Check two things: that the template-id names the same type as 1929 // CurClassType, and that the template-id does not occur when the name 1930 // was qualified. 1931 1932 return Context.DeclarationNames.getCXXConstructorName( 1933 Context.getCanonicalType(CurClassType)); 1934 } 1935 1936 case UnqualifiedId::IK_DestructorName: { 1937 QualType Ty = GetTypeFromParser(Name.DestructorName); 1938 if (Ty.isNull()) 1939 return DeclarationName(); 1940 1941 return Context.DeclarationNames.getCXXDestructorName( 1942 Context.getCanonicalType(Ty)); 1943 } 1944 1945 case UnqualifiedId::IK_TemplateId: { 1946 TemplateName TName 1947 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1948 return Context.getNameForTemplate(TName); 1949 } 1950 } 1951 1952 assert(false && "Unknown name kind"); 1953 return DeclarationName(); 1954} 1955 1956/// isNearlyMatchingFunction - Determine whether the C++ functions 1957/// Declaration and Definition are "nearly" matching. This heuristic 1958/// is used to improve diagnostics in the case where an out-of-line 1959/// function definition doesn't match any declaration within 1960/// the class or namespace. 1961static bool isNearlyMatchingFunction(ASTContext &Context, 1962 FunctionDecl *Declaration, 1963 FunctionDecl *Definition) { 1964 if (Declaration->param_size() != Definition->param_size()) 1965 return false; 1966 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1967 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1968 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1969 1970 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1971 DefParamTy.getNonReferenceType())) 1972 return false; 1973 } 1974 1975 return true; 1976} 1977 1978/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 1979/// declarator needs to be rebuilt in the current instantiation. 1980/// Any bits of declarator which appear before the name are valid for 1981/// consideration here. That's specifically the type in the decl spec 1982/// and the base type in any member-pointer chunks. 1983static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 1984 DeclarationName Name) { 1985 // The types we specifically need to rebuild are: 1986 // - typenames, typeofs, and decltypes 1987 // - types which will become injected class names 1988 // Of course, we also need to rebuild any type referencing such a 1989 // type. It's safest to just say "dependent", but we call out a 1990 // few cases here. 1991 1992 DeclSpec &DS = D.getMutableDeclSpec(); 1993 switch (DS.getTypeSpecType()) { 1994 case DeclSpec::TST_typename: 1995 case DeclSpec::TST_typeofType: 1996 case DeclSpec::TST_typeofExpr: 1997 case DeclSpec::TST_decltype: { 1998 // Grab the type from the parser. 1999 TypeSourceInfo *TSI = 0; 2000 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2001 if (T.isNull() || !T->isDependentType()) break; 2002 2003 // Make sure there's a type source info. This isn't really much 2004 // of a waste; most dependent types should have type source info 2005 // attached already. 2006 if (!TSI) 2007 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2008 2009 // Rebuild the type in the current instantiation. 2010 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2011 if (!TSI) return true; 2012 2013 // Store the new type back in the decl spec. 2014 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2015 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2016 break; 2017 } 2018 2019 default: 2020 // Nothing to do for these decl specs. 2021 break; 2022 } 2023 2024 // It doesn't matter what order we do this in. 2025 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2026 DeclaratorChunk &Chunk = D.getTypeObject(I); 2027 2028 // The only type information in the declarator which can come 2029 // before the declaration name is the base type of a member 2030 // pointer. 2031 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2032 continue; 2033 2034 // Rebuild the scope specifier in-place. 2035 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2036 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2037 return true; 2038 } 2039 2040 return false; 2041} 2042 2043Sema::DeclPtrTy 2044Sema::HandleDeclarator(Scope *S, Declarator &D, 2045 MultiTemplateParamsArg TemplateParamLists, 2046 bool IsFunctionDefinition) { 2047 DeclarationName Name = GetNameForDeclarator(D); 2048 2049 // All of these full declarators require an identifier. If it doesn't have 2050 // one, the ParsedFreeStandingDeclSpec action should be used. 2051 if (!Name) { 2052 if (!D.isInvalidType()) // Reject this if we think it is valid. 2053 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2054 diag::err_declarator_need_ident) 2055 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2056 return DeclPtrTy(); 2057 } 2058 2059 // The scope passed in may not be a decl scope. Zip up the scope tree until 2060 // we find one that is. 2061 while ((S->getFlags() & Scope::DeclScope) == 0 || 2062 (S->getFlags() & Scope::TemplateParamScope) != 0) 2063 S = S->getParent(); 2064 2065 DeclContext *DC = CurContext; 2066 if (D.getCXXScopeSpec().isInvalid()) 2067 D.setInvalidType(); 2068 else if (D.getCXXScopeSpec().isSet()) { 2069 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2070 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2071 if (!DC) { 2072 // If we could not compute the declaration context, it's because the 2073 // declaration context is dependent but does not refer to a class, 2074 // class template, or class template partial specialization. Complain 2075 // and return early, to avoid the coming semantic disaster. 2076 Diag(D.getIdentifierLoc(), 2077 diag::err_template_qualified_declarator_no_match) 2078 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2079 << D.getCXXScopeSpec().getRange(); 2080 return DeclPtrTy(); 2081 } 2082 2083 bool IsDependentContext = DC->isDependentContext(); 2084 2085 if (!IsDependentContext && 2086 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2087 return DeclPtrTy(); 2088 2089 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2090 Diag(D.getIdentifierLoc(), 2091 diag::err_member_def_undefined_record) 2092 << Name << DC << D.getCXXScopeSpec().getRange(); 2093 D.setInvalidType(); 2094 } 2095 2096 // Check whether we need to rebuild the type of the given 2097 // declaration in the current instantiation. 2098 if (EnteringContext && IsDependentContext && 2099 TemplateParamLists.size() != 0) { 2100 ContextRAII SavedContext(*this, DC); 2101 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2102 D.setInvalidType(); 2103 } 2104 } 2105 2106 NamedDecl *New; 2107 2108 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2109 QualType R = TInfo->getType(); 2110 2111 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2112 ForRedeclaration); 2113 2114 // See if this is a redefinition of a variable in the same scope. 2115 if (!D.getCXXScopeSpec().isSet()) { 2116 bool IsLinkageLookup = false; 2117 2118 // If the declaration we're planning to build will be a function 2119 // or object with linkage, then look for another declaration with 2120 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2121 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2122 /* Do nothing*/; 2123 else if (R->isFunctionType()) { 2124 if (CurContext->isFunctionOrMethod() || 2125 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2126 IsLinkageLookup = true; 2127 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2128 IsLinkageLookup = true; 2129 else if (CurContext->getLookupContext()->isTranslationUnit() && 2130 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2131 IsLinkageLookup = true; 2132 2133 if (IsLinkageLookup) 2134 Previous.clear(LookupRedeclarationWithLinkage); 2135 2136 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2137 } else { // Something like "int foo::x;" 2138 LookupQualifiedName(Previous, DC); 2139 2140 // Don't consider using declarations as previous declarations for 2141 // out-of-line members. 2142 RemoveUsingDecls(Previous); 2143 2144 // C++ 7.3.1.2p2: 2145 // Members (including explicit specializations of templates) of a named 2146 // namespace can also be defined outside that namespace by explicit 2147 // qualification of the name being defined, provided that the entity being 2148 // defined was already declared in the namespace and the definition appears 2149 // after the point of declaration in a namespace that encloses the 2150 // declarations namespace. 2151 // 2152 // Note that we only check the context at this point. We don't yet 2153 // have enough information to make sure that PrevDecl is actually 2154 // the declaration we want to match. For example, given: 2155 // 2156 // class X { 2157 // void f(); 2158 // void f(float); 2159 // }; 2160 // 2161 // void X::f(int) { } // ill-formed 2162 // 2163 // In this case, PrevDecl will point to the overload set 2164 // containing the two f's declared in X, but neither of them 2165 // matches. 2166 2167 // First check whether we named the global scope. 2168 if (isa<TranslationUnitDecl>(DC)) { 2169 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2170 << Name << D.getCXXScopeSpec().getRange(); 2171 } else { 2172 DeclContext *Cur = CurContext; 2173 while (isa<LinkageSpecDecl>(Cur)) 2174 Cur = Cur->getParent(); 2175 if (!Cur->Encloses(DC)) { 2176 // The qualifying scope doesn't enclose the original declaration. 2177 // Emit diagnostic based on current scope. 2178 SourceLocation L = D.getIdentifierLoc(); 2179 SourceRange R = D.getCXXScopeSpec().getRange(); 2180 if (isa<FunctionDecl>(Cur)) 2181 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2182 else 2183 Diag(L, diag::err_invalid_declarator_scope) 2184 << Name << cast<NamedDecl>(DC) << R; 2185 D.setInvalidType(); 2186 } 2187 } 2188 } 2189 2190 if (Previous.isSingleResult() && 2191 Previous.getFoundDecl()->isTemplateParameter()) { 2192 // Maybe we will complain about the shadowed template parameter. 2193 if (!D.isInvalidType()) 2194 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2195 Previous.getFoundDecl())) 2196 D.setInvalidType(); 2197 2198 // Just pretend that we didn't see the previous declaration. 2199 Previous.clear(); 2200 } 2201 2202 // In C++, the previous declaration we find might be a tag type 2203 // (class or enum). In this case, the new declaration will hide the 2204 // tag type. Note that this does does not apply if we're declaring a 2205 // typedef (C++ [dcl.typedef]p4). 2206 if (Previous.isSingleTagDecl() && 2207 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2208 Previous.clear(); 2209 2210 bool Redeclaration = false; 2211 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2212 if (TemplateParamLists.size()) { 2213 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2214 return DeclPtrTy(); 2215 } 2216 2217 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2218 } else if (R->isFunctionType()) { 2219 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2220 move(TemplateParamLists), 2221 IsFunctionDefinition, Redeclaration); 2222 } else { 2223 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2224 move(TemplateParamLists), 2225 Redeclaration); 2226 } 2227 2228 if (New == 0) 2229 return DeclPtrTy(); 2230 2231 // If this has an identifier and is not an invalid redeclaration or 2232 // function template specialization, add it to the scope stack. 2233 if (Name && !(Redeclaration && New->isInvalidDecl())) 2234 PushOnScopeChains(New, S); 2235 2236 return DeclPtrTy::make(New); 2237} 2238 2239/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2240/// types into constant array types in certain situations which would otherwise 2241/// be errors (for GCC compatibility). 2242static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2243 ASTContext &Context, 2244 bool &SizeIsNegative) { 2245 // This method tries to turn a variable array into a constant 2246 // array even when the size isn't an ICE. This is necessary 2247 // for compatibility with code that depends on gcc's buggy 2248 // constant expression folding, like struct {char x[(int)(char*)2];} 2249 SizeIsNegative = false; 2250 2251 QualifierCollector Qs; 2252 const Type *Ty = Qs.strip(T); 2253 2254 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2255 QualType Pointee = PTy->getPointeeType(); 2256 QualType FixedType = 2257 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2258 if (FixedType.isNull()) return FixedType; 2259 FixedType = Context.getPointerType(FixedType); 2260 return Qs.apply(FixedType); 2261 } 2262 2263 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2264 if (!VLATy) 2265 return QualType(); 2266 // FIXME: We should probably handle this case 2267 if (VLATy->getElementType()->isVariablyModifiedType()) 2268 return QualType(); 2269 2270 Expr::EvalResult EvalResult; 2271 if (!VLATy->getSizeExpr() || 2272 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2273 !EvalResult.Val.isInt()) 2274 return QualType(); 2275 2276 llvm::APSInt &Res = EvalResult.Val.getInt(); 2277 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2278 // TODO: preserve the size expression in declarator info 2279 return Context.getConstantArrayType(VLATy->getElementType(), 2280 Res, ArrayType::Normal, 0); 2281 } 2282 2283 SizeIsNegative = true; 2284 return QualType(); 2285} 2286 2287/// \brief Register the given locally-scoped external C declaration so 2288/// that it can be found later for redeclarations 2289void 2290Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2291 const LookupResult &Previous, 2292 Scope *S) { 2293 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2294 "Decl is not a locally-scoped decl!"); 2295 // Note that we have a locally-scoped external with this name. 2296 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2297 2298 if (!Previous.isSingleResult()) 2299 return; 2300 2301 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2302 2303 // If there was a previous declaration of this variable, it may be 2304 // in our identifier chain. Update the identifier chain with the new 2305 // declaration. 2306 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2307 // The previous declaration was found on the identifer resolver 2308 // chain, so remove it from its scope. 2309 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2310 S = S->getParent(); 2311 2312 if (S) 2313 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2314 } 2315} 2316 2317/// \brief Diagnose function specifiers on a declaration of an identifier that 2318/// does not identify a function. 2319void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2320 // FIXME: We should probably indicate the identifier in question to avoid 2321 // confusion for constructs like "inline int a(), b;" 2322 if (D.getDeclSpec().isInlineSpecified()) 2323 Diag(D.getDeclSpec().getInlineSpecLoc(), 2324 diag::err_inline_non_function); 2325 2326 if (D.getDeclSpec().isVirtualSpecified()) 2327 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2328 diag::err_virtual_non_function); 2329 2330 if (D.getDeclSpec().isExplicitSpecified()) 2331 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2332 diag::err_explicit_non_function); 2333} 2334 2335NamedDecl* 2336Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2337 QualType R, TypeSourceInfo *TInfo, 2338 LookupResult &Previous, bool &Redeclaration) { 2339 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2340 if (D.getCXXScopeSpec().isSet()) { 2341 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2342 << D.getCXXScopeSpec().getRange(); 2343 D.setInvalidType(); 2344 // Pretend we didn't see the scope specifier. 2345 DC = CurContext; 2346 Previous.clear(); 2347 } 2348 2349 if (getLangOptions().CPlusPlus) { 2350 // Check that there are no default arguments (C++ only). 2351 CheckExtraCXXDefaultArguments(D); 2352 } 2353 2354 DiagnoseFunctionSpecifiers(D); 2355 2356 if (D.getDeclSpec().isThreadSpecified()) 2357 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2358 2359 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2360 if (!NewTD) return 0; 2361 2362 // Handle attributes prior to checking for duplicates in MergeVarDecl 2363 ProcessDeclAttributes(S, NewTD, D); 2364 2365 // Merge the decl with the existing one if appropriate. If the decl is 2366 // in an outer scope, it isn't the same thing. 2367 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2368 if (!Previous.empty()) { 2369 Redeclaration = true; 2370 MergeTypeDefDecl(NewTD, Previous); 2371 } 2372 2373 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2374 // then it shall have block scope. 2375 QualType T = NewTD->getUnderlyingType(); 2376 if (T->isVariablyModifiedType()) { 2377 FunctionNeedsScopeChecking() = true; 2378 2379 if (S->getFnParent() == 0) { 2380 bool SizeIsNegative; 2381 QualType FixedTy = 2382 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2383 if (!FixedTy.isNull()) { 2384 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2385 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2386 } else { 2387 if (SizeIsNegative) 2388 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2389 else if (T->isVariableArrayType()) 2390 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2391 else 2392 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2393 NewTD->setInvalidDecl(); 2394 } 2395 } 2396 } 2397 2398 // If this is the C FILE type, notify the AST context. 2399 if (IdentifierInfo *II = NewTD->getIdentifier()) 2400 if (!NewTD->isInvalidDecl() && 2401 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2402 if (II->isStr("FILE")) 2403 Context.setFILEDecl(NewTD); 2404 else if (II->isStr("jmp_buf")) 2405 Context.setjmp_bufDecl(NewTD); 2406 else if (II->isStr("sigjmp_buf")) 2407 Context.setsigjmp_bufDecl(NewTD); 2408 } 2409 2410 return NewTD; 2411} 2412 2413/// \brief Determines whether the given declaration is an out-of-scope 2414/// previous declaration. 2415/// 2416/// This routine should be invoked when name lookup has found a 2417/// previous declaration (PrevDecl) that is not in the scope where a 2418/// new declaration by the same name is being introduced. If the new 2419/// declaration occurs in a local scope, previous declarations with 2420/// linkage may still be considered previous declarations (C99 2421/// 6.2.2p4-5, C++ [basic.link]p6). 2422/// 2423/// \param PrevDecl the previous declaration found by name 2424/// lookup 2425/// 2426/// \param DC the context in which the new declaration is being 2427/// declared. 2428/// 2429/// \returns true if PrevDecl is an out-of-scope previous declaration 2430/// for a new delcaration with the same name. 2431static bool 2432isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2433 ASTContext &Context) { 2434 if (!PrevDecl) 2435 return 0; 2436 2437 if (!PrevDecl->hasLinkage()) 2438 return false; 2439 2440 if (Context.getLangOptions().CPlusPlus) { 2441 // C++ [basic.link]p6: 2442 // If there is a visible declaration of an entity with linkage 2443 // having the same name and type, ignoring entities declared 2444 // outside the innermost enclosing namespace scope, the block 2445 // scope declaration declares that same entity and receives the 2446 // linkage of the previous declaration. 2447 DeclContext *OuterContext = DC->getLookupContext(); 2448 if (!OuterContext->isFunctionOrMethod()) 2449 // This rule only applies to block-scope declarations. 2450 return false; 2451 else { 2452 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2453 if (PrevOuterContext->isRecord()) 2454 // We found a member function: ignore it. 2455 return false; 2456 else { 2457 // Find the innermost enclosing namespace for the new and 2458 // previous declarations. 2459 while (!OuterContext->isFileContext()) 2460 OuterContext = OuterContext->getParent(); 2461 while (!PrevOuterContext->isFileContext()) 2462 PrevOuterContext = PrevOuterContext->getParent(); 2463 2464 // The previous declaration is in a different namespace, so it 2465 // isn't the same function. 2466 if (OuterContext->getPrimaryContext() != 2467 PrevOuterContext->getPrimaryContext()) 2468 return false; 2469 } 2470 } 2471 } 2472 2473 return true; 2474} 2475 2476static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2477 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2478 if (!SS.isSet()) return; 2479 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2480 SS.getRange()); 2481} 2482 2483NamedDecl* 2484Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2485 QualType R, TypeSourceInfo *TInfo, 2486 LookupResult &Previous, 2487 MultiTemplateParamsArg TemplateParamLists, 2488 bool &Redeclaration) { 2489 DeclarationName Name = GetNameForDeclarator(D); 2490 2491 // Check that there are no default arguments (C++ only). 2492 if (getLangOptions().CPlusPlus) 2493 CheckExtraCXXDefaultArguments(D); 2494 2495 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2496 assert(SCSpec != DeclSpec::SCS_typedef && 2497 "Parser allowed 'typedef' as storage class VarDecl."); 2498 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 2499 if (SCSpec == DeclSpec::SCS_mutable) { 2500 // mutable can only appear on non-static class members, so it's always 2501 // an error here 2502 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2503 D.setInvalidType(); 2504 SC = VarDecl::None; 2505 } 2506 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2507 VarDecl::StorageClass SCAsWritten 2508 = StorageClassSpecToVarDeclStorageClass(SCSpec, DC); 2509 2510 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2511 if (!II) { 2512 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2513 << Name.getAsString(); 2514 return 0; 2515 } 2516 2517 DiagnoseFunctionSpecifiers(D); 2518 2519 if (!DC->isRecord() && S->getFnParent() == 0) { 2520 // C99 6.9p2: The storage-class specifiers auto and register shall not 2521 // appear in the declaration specifiers in an external declaration. 2522 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2523 2524 // If this is a register variable with an asm label specified, then this 2525 // is a GNU extension. 2526 if (SC == VarDecl::Register && D.getAsmLabel()) 2527 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2528 else 2529 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2530 D.setInvalidType(); 2531 } 2532 } 2533 if (DC->isRecord() && !CurContext->isRecord()) { 2534 // This is an out-of-line definition of a static data member. 2535 if (SC == VarDecl::Static) { 2536 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2537 diag::err_static_out_of_line) 2538 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2539 } else if (SC == VarDecl::None) 2540 SC = VarDecl::Static; 2541 } 2542 if (SC == VarDecl::Static) { 2543 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2544 if (RD->isLocalClass()) 2545 Diag(D.getIdentifierLoc(), 2546 diag::err_static_data_member_not_allowed_in_local_class) 2547 << Name << RD->getDeclName(); 2548 } 2549 } 2550 2551 // Match up the template parameter lists with the scope specifier, then 2552 // determine whether we have a template or a template specialization. 2553 bool isExplicitSpecialization = false; 2554 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2555 if (TemplateParameterList *TemplateParams 2556 = MatchTemplateParametersToScopeSpecifier( 2557 D.getDeclSpec().getSourceRange().getBegin(), 2558 D.getCXXScopeSpec(), 2559 (TemplateParameterList**)TemplateParamLists.get(), 2560 TemplateParamLists.size(), 2561 /*never a friend*/ false, 2562 isExplicitSpecialization)) { 2563 // All but one template parameter lists have been matching. 2564 --NumMatchedTemplateParamLists; 2565 2566 if (TemplateParams->size() > 0) { 2567 // There is no such thing as a variable template. 2568 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2569 << II 2570 << SourceRange(TemplateParams->getTemplateLoc(), 2571 TemplateParams->getRAngleLoc()); 2572 return 0; 2573 } else { 2574 // There is an extraneous 'template<>' for this variable. Complain 2575 // about it, but allow the declaration of the variable. 2576 Diag(TemplateParams->getTemplateLoc(), 2577 diag::err_template_variable_noparams) 2578 << II 2579 << SourceRange(TemplateParams->getTemplateLoc(), 2580 TemplateParams->getRAngleLoc()); 2581 2582 isExplicitSpecialization = true; 2583 } 2584 } 2585 2586 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2587 II, R, TInfo, SC, SCAsWritten); 2588 2589 if (D.isInvalidType()) 2590 NewVD->setInvalidDecl(); 2591 2592 SetNestedNameSpecifier(NewVD, D); 2593 2594 if (NumMatchedTemplateParamLists > 0) { 2595 NewVD->setTemplateParameterListsInfo(Context, 2596 NumMatchedTemplateParamLists, 2597 (TemplateParameterList**)TemplateParamLists.release()); 2598 } 2599 2600 if (D.getDeclSpec().isThreadSpecified()) { 2601 if (NewVD->hasLocalStorage()) 2602 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2603 else if (!Context.Target.isTLSSupported()) 2604 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2605 else 2606 NewVD->setThreadSpecified(true); 2607 } 2608 2609 // Set the lexical context. If the declarator has a C++ scope specifier, the 2610 // lexical context will be different from the semantic context. 2611 NewVD->setLexicalDeclContext(CurContext); 2612 2613 // Handle attributes prior to checking for duplicates in MergeVarDecl 2614 ProcessDeclAttributes(S, NewVD, D); 2615 2616 // Handle GNU asm-label extension (encoded as an attribute). 2617 if (Expr *E = (Expr*) D.getAsmLabel()) { 2618 // The parser guarantees this is a string. 2619 StringLiteral *SE = cast<StringLiteral>(E); 2620 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2621 } 2622 2623 // Diagnose shadowed variables before filtering for scope. 2624 if (!D.getCXXScopeSpec().isSet()) 2625 CheckShadow(S, NewVD, Previous); 2626 2627 // Don't consider existing declarations that are in a different 2628 // scope and are out-of-semantic-context declarations (if the new 2629 // declaration has linkage). 2630 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2631 2632 // Merge the decl with the existing one if appropriate. 2633 if (!Previous.empty()) { 2634 if (Previous.isSingleResult() && 2635 isa<FieldDecl>(Previous.getFoundDecl()) && 2636 D.getCXXScopeSpec().isSet()) { 2637 // The user tried to define a non-static data member 2638 // out-of-line (C++ [dcl.meaning]p1). 2639 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2640 << D.getCXXScopeSpec().getRange(); 2641 Previous.clear(); 2642 NewVD->setInvalidDecl(); 2643 } 2644 } else if (D.getCXXScopeSpec().isSet()) { 2645 // No previous declaration in the qualifying scope. 2646 Diag(D.getIdentifierLoc(), diag::err_no_member) 2647 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2648 << D.getCXXScopeSpec().getRange(); 2649 NewVD->setInvalidDecl(); 2650 } 2651 2652 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2653 2654 // This is an explicit specialization of a static data member. Check it. 2655 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2656 CheckMemberSpecialization(NewVD, Previous)) 2657 NewVD->setInvalidDecl(); 2658 2659 // attributes declared post-definition are currently ignored 2660 if (Previous.isSingleResult()) { 2661 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2662 if (Def && (Def = Def->getDefinition()) && 2663 Def != NewVD && D.hasAttributes()) { 2664 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2665 Diag(Def->getLocation(), diag::note_previous_definition); 2666 } 2667 } 2668 2669 // If this is a locally-scoped extern C variable, update the map of 2670 // such variables. 2671 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2672 !NewVD->isInvalidDecl()) 2673 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2674 2675 return NewVD; 2676} 2677 2678/// \brief Diagnose variable or built-in function shadowing. Implements 2679/// -Wshadow. 2680/// 2681/// This method is called whenever a VarDecl is added to a "useful" 2682/// scope. 2683/// 2684/// \param S the scope in which the shadowing name is being declared 2685/// \param R the lookup of the name 2686/// 2687void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2688 // Return if warning is ignored. 2689 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2690 return; 2691 2692 // Don't diagnose declarations at file scope. The scope might not 2693 // have a DeclContext if (e.g.) we're parsing a function prototype. 2694 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2695 if (NewDC && NewDC->isFileContext()) 2696 return; 2697 2698 // Only diagnose if we're shadowing an unambiguous field or variable. 2699 if (R.getResultKind() != LookupResult::Found) 2700 return; 2701 2702 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2703 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2704 return; 2705 2706 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2707 2708 // Only warn about certain kinds of shadowing for class members. 2709 if (NewDC && NewDC->isRecord()) { 2710 // In particular, don't warn about shadowing non-class members. 2711 if (!OldDC->isRecord()) 2712 return; 2713 2714 // TODO: should we warn about static data members shadowing 2715 // static data members from base classes? 2716 2717 // TODO: don't diagnose for inaccessible shadowed members. 2718 // This is hard to do perfectly because we might friend the 2719 // shadowing context, but that's just a false negative. 2720 } 2721 2722 // Determine what kind of declaration we're shadowing. 2723 unsigned Kind; 2724 if (isa<RecordDecl>(OldDC)) { 2725 if (isa<FieldDecl>(ShadowedDecl)) 2726 Kind = 3; // field 2727 else 2728 Kind = 2; // static data member 2729 } else if (OldDC->isFileContext()) 2730 Kind = 1; // global 2731 else 2732 Kind = 0; // local 2733 2734 DeclarationName Name = R.getLookupName(); 2735 2736 // Emit warning and note. 2737 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2738 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2739} 2740 2741/// \brief Check -Wshadow without the advantage of a previous lookup. 2742void Sema::CheckShadow(Scope *S, VarDecl *D) { 2743 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2744 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2745 LookupName(R, S); 2746 CheckShadow(S, D, R); 2747} 2748 2749/// \brief Perform semantic checking on a newly-created variable 2750/// declaration. 2751/// 2752/// This routine performs all of the type-checking required for a 2753/// variable declaration once it has been built. It is used both to 2754/// check variables after they have been parsed and their declarators 2755/// have been translated into a declaration, and to check variables 2756/// that have been instantiated from a template. 2757/// 2758/// Sets NewVD->isInvalidDecl() if an error was encountered. 2759void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2760 LookupResult &Previous, 2761 bool &Redeclaration) { 2762 // If the decl is already known invalid, don't check it. 2763 if (NewVD->isInvalidDecl()) 2764 return; 2765 2766 QualType T = NewVD->getType(); 2767 2768 if (T->isObjCObjectType()) { 2769 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2770 return NewVD->setInvalidDecl(); 2771 } 2772 2773 // Emit an error if an address space was applied to decl with local storage. 2774 // This includes arrays of objects with address space qualifiers, but not 2775 // automatic variables that point to other address spaces. 2776 // ISO/IEC TR 18037 S5.1.2 2777 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2778 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2779 return NewVD->setInvalidDecl(); 2780 } 2781 2782 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2783 && !NewVD->hasAttr<BlocksAttr>()) 2784 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2785 2786 bool isVM = T->isVariablyModifiedType(); 2787 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2788 NewVD->hasAttr<BlocksAttr>() || 2789 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2790 // However, this turns on the scope checker for everything with a variable 2791 // which may impact compile time. See if we can find a better solution 2792 // to this, perhaps only checking functions that contain gotos in C++? 2793 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2794 FunctionNeedsScopeChecking() = true; 2795 2796 if ((isVM && NewVD->hasLinkage()) || 2797 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2798 bool SizeIsNegative; 2799 QualType FixedTy = 2800 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2801 2802 if (FixedTy.isNull() && T->isVariableArrayType()) { 2803 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2804 // FIXME: This won't give the correct result for 2805 // int a[10][n]; 2806 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2807 2808 if (NewVD->isFileVarDecl()) 2809 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2810 << SizeRange; 2811 else if (NewVD->getStorageClass() == VarDecl::Static) 2812 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2813 << SizeRange; 2814 else 2815 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2816 << SizeRange; 2817 return NewVD->setInvalidDecl(); 2818 } 2819 2820 if (FixedTy.isNull()) { 2821 if (NewVD->isFileVarDecl()) 2822 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2823 else 2824 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2825 return NewVD->setInvalidDecl(); 2826 } 2827 2828 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2829 NewVD->setType(FixedTy); 2830 } 2831 2832 if (Previous.empty() && NewVD->isExternC()) { 2833 // Since we did not find anything by this name and we're declaring 2834 // an extern "C" variable, look for a non-visible extern "C" 2835 // declaration with the same name. 2836 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2837 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2838 if (Pos != LocallyScopedExternalDecls.end()) 2839 Previous.addDecl(Pos->second); 2840 } 2841 2842 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2843 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2844 << T; 2845 return NewVD->setInvalidDecl(); 2846 } 2847 2848 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2849 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2850 return NewVD->setInvalidDecl(); 2851 } 2852 2853 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2854 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2855 return NewVD->setInvalidDecl(); 2856 } 2857 2858 if (!Previous.empty()) { 2859 Redeclaration = true; 2860 MergeVarDecl(NewVD, Previous); 2861 } 2862} 2863 2864/// \brief Data used with FindOverriddenMethod 2865struct FindOverriddenMethodData { 2866 Sema *S; 2867 CXXMethodDecl *Method; 2868}; 2869 2870/// \brief Member lookup function that determines whether a given C++ 2871/// method overrides a method in a base class, to be used with 2872/// CXXRecordDecl::lookupInBases(). 2873static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2874 CXXBasePath &Path, 2875 void *UserData) { 2876 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2877 2878 FindOverriddenMethodData *Data 2879 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2880 2881 DeclarationName Name = Data->Method->getDeclName(); 2882 2883 // FIXME: Do we care about other names here too? 2884 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2885 // We really want to find the base class destructor here. 2886 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2887 CanQualType CT = Data->S->Context.getCanonicalType(T); 2888 2889 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2890 } 2891 2892 for (Path.Decls = BaseRecord->lookup(Name); 2893 Path.Decls.first != Path.Decls.second; 2894 ++Path.Decls.first) { 2895 NamedDecl *D = *Path.Decls.first; 2896 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 2897 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 2898 return true; 2899 } 2900 } 2901 2902 return false; 2903} 2904 2905/// AddOverriddenMethods - See if a method overrides any in the base classes, 2906/// and if so, check that it's a valid override and remember it. 2907void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2908 // Look for virtual methods in base classes that this method might override. 2909 CXXBasePaths Paths; 2910 FindOverriddenMethodData Data; 2911 Data.Method = MD; 2912 Data.S = this; 2913 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2914 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2915 E = Paths.found_decls_end(); I != E; ++I) { 2916 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2917 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2918 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2919 !CheckOverridingFunctionAttributes(MD, OldMD)) 2920 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2921 } 2922 } 2923 } 2924} 2925 2926NamedDecl* 2927Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2928 QualType R, TypeSourceInfo *TInfo, 2929 LookupResult &Previous, 2930 MultiTemplateParamsArg TemplateParamLists, 2931 bool IsFunctionDefinition, bool &Redeclaration) { 2932 assert(R.getTypePtr()->isFunctionType()); 2933 2934 DeclarationName Name = GetNameForDeclarator(D); 2935 FunctionDecl::StorageClass SC = FunctionDecl::None; 2936 switch (D.getDeclSpec().getStorageClassSpec()) { 2937 default: assert(0 && "Unknown storage class!"); 2938 case DeclSpec::SCS_auto: 2939 case DeclSpec::SCS_register: 2940 case DeclSpec::SCS_mutable: 2941 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2942 diag::err_typecheck_sclass_func); 2943 D.setInvalidType(); 2944 break; 2945 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2946 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2947 case DeclSpec::SCS_static: { 2948 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2949 // C99 6.7.1p5: 2950 // The declaration of an identifier for a function that has 2951 // block scope shall have no explicit storage-class specifier 2952 // other than extern 2953 // See also (C++ [dcl.stc]p4). 2954 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2955 diag::err_static_block_func); 2956 SC = FunctionDecl::None; 2957 } else 2958 SC = FunctionDecl::Static; 2959 break; 2960 } 2961 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2962 } 2963 2964 if (D.getDeclSpec().isThreadSpecified()) 2965 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2966 2967 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2968 bool isInline = D.getDeclSpec().isInlineSpecified(); 2969 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2970 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2971 2972 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2973 FunctionDecl::StorageClass SCAsWritten 2974 = StorageClassSpecToFunctionDeclStorageClass(SCSpec, DC); 2975 2976 // Check that the return type is not an abstract class type. 2977 // For record types, this is done by the AbstractClassUsageDiagnoser once 2978 // the class has been completely parsed. 2979 if (!DC->isRecord() && 2980 RequireNonAbstractType(D.getIdentifierLoc(), 2981 R->getAs<FunctionType>()->getResultType(), 2982 diag::err_abstract_type_in_decl, 2983 AbstractReturnType)) 2984 D.setInvalidType(); 2985 2986 // Do not allow returning a objc interface by-value. 2987 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 2988 Diag(D.getIdentifierLoc(), 2989 diag::err_object_cannot_be_passed_returned_by_value) << 0 2990 << R->getAs<FunctionType>()->getResultType(); 2991 D.setInvalidType(); 2992 } 2993 2994 bool isVirtualOkay = false; 2995 FunctionDecl *NewFD; 2996 2997 if (isFriend) { 2998 // C++ [class.friend]p5 2999 // A function can be defined in a friend declaration of a 3000 // class . . . . Such a function is implicitly inline. 3001 isInline |= IsFunctionDefinition; 3002 } 3003 3004 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3005 // This is a C++ constructor declaration. 3006 assert(DC->isRecord() && 3007 "Constructors can only be declared in a member context"); 3008 3009 R = CheckConstructorDeclarator(D, R, SC); 3010 3011 // Create the new declaration 3012 NewFD = CXXConstructorDecl::Create(Context, 3013 cast<CXXRecordDecl>(DC), 3014 D.getIdentifierLoc(), Name, R, TInfo, 3015 isExplicit, isInline, 3016 /*isImplicitlyDeclared=*/false); 3017 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3018 // This is a C++ destructor declaration. 3019 if (DC->isRecord()) { 3020 R = CheckDestructorDeclarator(D, SC); 3021 3022 NewFD = CXXDestructorDecl::Create(Context, 3023 cast<CXXRecordDecl>(DC), 3024 D.getIdentifierLoc(), Name, R, 3025 isInline, 3026 /*isImplicitlyDeclared=*/false); 3027 NewFD->setTypeSourceInfo(TInfo); 3028 3029 isVirtualOkay = true; 3030 } else { 3031 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3032 3033 // Create a FunctionDecl to satisfy the function definition parsing 3034 // code path. 3035 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3036 Name, R, TInfo, SC, SCAsWritten, isInline, 3037 /*hasPrototype=*/true); 3038 D.setInvalidType(); 3039 } 3040 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3041 if (!DC->isRecord()) { 3042 Diag(D.getIdentifierLoc(), 3043 diag::err_conv_function_not_member); 3044 return 0; 3045 } 3046 3047 CheckConversionDeclarator(D, R, SC); 3048 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3049 D.getIdentifierLoc(), Name, R, TInfo, 3050 isInline, isExplicit); 3051 3052 isVirtualOkay = true; 3053 } else if (DC->isRecord()) { 3054 // If the of the function is the same as the name of the record, then this 3055 // must be an invalid constructor that has a return type. 3056 // (The parser checks for a return type and makes the declarator a 3057 // constructor if it has no return type). 3058 // must have an invalid constructor that has a return type 3059 if (Name.getAsIdentifierInfo() && 3060 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3061 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3062 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3063 << SourceRange(D.getIdentifierLoc()); 3064 return 0; 3065 } 3066 3067 bool isStatic = SC == FunctionDecl::Static; 3068 3069 // [class.free]p1: 3070 // Any allocation function for a class T is a static member 3071 // (even if not explicitly declared static). 3072 if (Name.getCXXOverloadedOperator() == OO_New || 3073 Name.getCXXOverloadedOperator() == OO_Array_New) 3074 isStatic = true; 3075 3076 // [class.free]p6 Any deallocation function for a class X is a static member 3077 // (even if not explicitly declared static). 3078 if (Name.getCXXOverloadedOperator() == OO_Delete || 3079 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3080 isStatic = true; 3081 3082 // This is a C++ method declaration. 3083 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3084 D.getIdentifierLoc(), Name, R, TInfo, 3085 isStatic, SCAsWritten, isInline); 3086 3087 isVirtualOkay = !isStatic; 3088 } else { 3089 // Determine whether the function was written with a 3090 // prototype. This true when: 3091 // - we're in C++ (where every function has a prototype), 3092 // - there is a prototype in the declarator, or 3093 // - the type R of the function is some kind of typedef or other reference 3094 // to a type name (which eventually refers to a function type). 3095 bool HasPrototype = 3096 getLangOptions().CPlusPlus || 3097 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3098 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3099 3100 NewFD = FunctionDecl::Create(Context, DC, 3101 D.getIdentifierLoc(), 3102 Name, R, TInfo, SC, SCAsWritten, isInline, 3103 HasPrototype); 3104 } 3105 3106 if (D.isInvalidType()) 3107 NewFD->setInvalidDecl(); 3108 3109 SetNestedNameSpecifier(NewFD, D); 3110 3111 // Set the lexical context. If the declarator has a C++ 3112 // scope specifier, or is the object of a friend declaration, the 3113 // lexical context will be different from the semantic context. 3114 NewFD->setLexicalDeclContext(CurContext); 3115 3116 // Match up the template parameter lists with the scope specifier, then 3117 // determine whether we have a template or a template specialization. 3118 FunctionTemplateDecl *FunctionTemplate = 0; 3119 bool isExplicitSpecialization = false; 3120 bool isFunctionTemplateSpecialization = false; 3121 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3122 if (TemplateParameterList *TemplateParams 3123 = MatchTemplateParametersToScopeSpecifier( 3124 D.getDeclSpec().getSourceRange().getBegin(), 3125 D.getCXXScopeSpec(), 3126 (TemplateParameterList**)TemplateParamLists.get(), 3127 TemplateParamLists.size(), 3128 isFriend, 3129 isExplicitSpecialization)) { 3130 // All but one template parameter lists have been matching. 3131 --NumMatchedTemplateParamLists; 3132 3133 if (TemplateParams->size() > 0) { 3134 // This is a function template 3135 3136 // Check that we can declare a template here. 3137 if (CheckTemplateDeclScope(S, TemplateParams)) 3138 return 0; 3139 3140 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3141 NewFD->getLocation(), 3142 Name, TemplateParams, 3143 NewFD); 3144 FunctionTemplate->setLexicalDeclContext(CurContext); 3145 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3146 } else { 3147 // This is a function template specialization. 3148 isFunctionTemplateSpecialization = true; 3149 3150 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3151 if (isFriend && isFunctionTemplateSpecialization) { 3152 // We want to remove the "template<>", found here. 3153 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3154 3155 // If we remove the template<> and the name is not a 3156 // template-id, we're actually silently creating a problem: 3157 // the friend declaration will refer to an untemplated decl, 3158 // and clearly the user wants a template specialization. So 3159 // we need to insert '<>' after the name. 3160 SourceLocation InsertLoc; 3161 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3162 InsertLoc = D.getName().getSourceRange().getEnd(); 3163 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3164 } 3165 3166 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3167 << Name << RemoveRange 3168 << FixItHint::CreateRemoval(RemoveRange) 3169 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3170 } 3171 } 3172 } 3173 3174 if (NumMatchedTemplateParamLists > 0) { 3175 NewFD->setTemplateParameterListsInfo(Context, 3176 NumMatchedTemplateParamLists, 3177 (TemplateParameterList**)TemplateParamLists.release()); 3178 } 3179 3180 // C++ [dcl.fct.spec]p5: 3181 // The virtual specifier shall only be used in declarations of 3182 // nonstatic class member functions that appear within a 3183 // member-specification of a class declaration; see 10.3. 3184 // 3185 if (isVirtual && !NewFD->isInvalidDecl()) { 3186 if (!isVirtualOkay) { 3187 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3188 diag::err_virtual_non_function); 3189 } else if (!CurContext->isRecord()) { 3190 // 'virtual' was specified outside of the class. 3191 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3192 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3193 } else { 3194 // Okay: Add virtual to the method. 3195 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3196 CurClass->setMethodAsVirtual(NewFD); 3197 } 3198 } 3199 3200 // C++ [dcl.fct.spec]p6: 3201 // The explicit specifier shall be used only in the declaration of a 3202 // constructor or conversion function within its class definition; see 12.3.1 3203 // and 12.3.2. 3204 if (isExplicit && !NewFD->isInvalidDecl()) { 3205 if (!CurContext->isRecord()) { 3206 // 'explicit' was specified outside of the class. 3207 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3208 diag::err_explicit_out_of_class) 3209 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3210 } else if (!isa<CXXConstructorDecl>(NewFD) && 3211 !isa<CXXConversionDecl>(NewFD)) { 3212 // 'explicit' was specified on a function that wasn't a constructor 3213 // or conversion function. 3214 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3215 diag::err_explicit_non_ctor_or_conv_function) 3216 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3217 } 3218 } 3219 3220 // Filter out previous declarations that don't match the scope. 3221 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3222 3223 if (isFriend) { 3224 // DC is the namespace in which the function is being declared. 3225 assert((DC->isFileContext() || !Previous.empty()) && 3226 "previously-undeclared friend function being created " 3227 "in a non-namespace context"); 3228 3229 // For now, claim that the objects have no previous declaration. 3230 if (FunctionTemplate) { 3231 FunctionTemplate->setObjectOfFriendDecl(false); 3232 FunctionTemplate->setAccess(AS_public); 3233 } 3234 NewFD->setObjectOfFriendDecl(false); 3235 NewFD->setAccess(AS_public); 3236 } 3237 3238 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3239 !CurContext->isRecord()) { 3240 // C++ [class.static]p1: 3241 // A data or function member of a class may be declared static 3242 // in a class definition, in which case it is a static member of 3243 // the class. 3244 3245 // Complain about the 'static' specifier if it's on an out-of-line 3246 // member function definition. 3247 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3248 diag::err_static_out_of_line) 3249 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3250 } 3251 3252 // Handle GNU asm-label extension (encoded as an attribute). 3253 if (Expr *E = (Expr*) D.getAsmLabel()) { 3254 // The parser guarantees this is a string. 3255 StringLiteral *SE = cast<StringLiteral>(E); 3256 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3257 } 3258 3259 // Copy the parameter declarations from the declarator D to the function 3260 // declaration NewFD, if they are available. First scavenge them into Params. 3261 llvm::SmallVector<ParmVarDecl*, 16> Params; 3262 if (D.getNumTypeObjects() > 0) { 3263 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3264 3265 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3266 // function that takes no arguments, not a function that takes a 3267 // single void argument. 3268 // We let through "const void" here because Sema::GetTypeForDeclarator 3269 // already checks for that case. 3270 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3271 FTI.ArgInfo[0].Param && 3272 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3273 // Empty arg list, don't push any params. 3274 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3275 3276 // In C++, the empty parameter-type-list must be spelled "void"; a 3277 // typedef of void is not permitted. 3278 if (getLangOptions().CPlusPlus && 3279 Param->getType().getUnqualifiedType() != Context.VoidTy) 3280 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3281 // FIXME: Leaks decl? 3282 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3283 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3284 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3285 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3286 Param->setDeclContext(NewFD); 3287 Params.push_back(Param); 3288 3289 if (Param->isInvalidDecl()) 3290 NewFD->setInvalidDecl(); 3291 } 3292 } 3293 3294 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3295 // When we're declaring a function with a typedef, typeof, etc as in the 3296 // following example, we'll need to synthesize (unnamed) 3297 // parameters for use in the declaration. 3298 // 3299 // @code 3300 // typedef void fn(int); 3301 // fn f; 3302 // @endcode 3303 3304 // Synthesize a parameter for each argument type. 3305 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3306 AE = FT->arg_type_end(); AI != AE; ++AI) { 3307 ParmVarDecl *Param = 3308 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3309 Params.push_back(Param); 3310 } 3311 } else { 3312 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3313 "Should not need args for typedef of non-prototype fn"); 3314 } 3315 // Finally, we know we have the right number of parameters, install them. 3316 NewFD->setParams(Params.data(), Params.size()); 3317 3318 // If the declarator is a template-id, translate the parser's template 3319 // argument list into our AST format. 3320 bool HasExplicitTemplateArgs = false; 3321 TemplateArgumentListInfo TemplateArgs; 3322 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3323 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3324 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3325 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3326 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3327 TemplateId->getTemplateArgs(), 3328 TemplateId->NumArgs); 3329 translateTemplateArguments(TemplateArgsPtr, 3330 TemplateArgs); 3331 TemplateArgsPtr.release(); 3332 3333 HasExplicitTemplateArgs = true; 3334 3335 if (FunctionTemplate) { 3336 // FIXME: Diagnose function template with explicit template 3337 // arguments. 3338 HasExplicitTemplateArgs = false; 3339 } else if (!isFunctionTemplateSpecialization && 3340 !D.getDeclSpec().isFriendSpecified()) { 3341 // We have encountered something that the user meant to be a 3342 // specialization (because it has explicitly-specified template 3343 // arguments) but that was not introduced with a "template<>" (or had 3344 // too few of them). 3345 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3346 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3347 << FixItHint::CreateInsertion( 3348 D.getDeclSpec().getSourceRange().getBegin(), 3349 "template<> "); 3350 isFunctionTemplateSpecialization = true; 3351 } else { 3352 // "friend void foo<>(int);" is an implicit specialization decl. 3353 isFunctionTemplateSpecialization = true; 3354 } 3355 } else if (isFriend && isFunctionTemplateSpecialization) { 3356 // This combination is only possible in a recovery case; the user 3357 // wrote something like: 3358 // template <> friend void foo(int); 3359 // which we're recovering from as if the user had written: 3360 // friend void foo<>(int); 3361 // Go ahead and fake up a template id. 3362 HasExplicitTemplateArgs = true; 3363 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3364 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3365 } 3366 3367 // If it's a friend (and only if it's a friend), it's possible 3368 // that either the specialized function type or the specialized 3369 // template is dependent, and therefore matching will fail. In 3370 // this case, don't check the specialization yet. 3371 if (isFunctionTemplateSpecialization && isFriend && 3372 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3373 assert(HasExplicitTemplateArgs && 3374 "friend function specialization without template args"); 3375 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3376 Previous)) 3377 NewFD->setInvalidDecl(); 3378 } else if (isFunctionTemplateSpecialization) { 3379 if (CheckFunctionTemplateSpecialization(NewFD, 3380 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3381 Previous)) 3382 NewFD->setInvalidDecl(); 3383 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3384 if (CheckMemberSpecialization(NewFD, Previous)) 3385 NewFD->setInvalidDecl(); 3386 } 3387 3388 // Perform semantic checking on the function declaration. 3389 bool OverloadableAttrRequired = false; // FIXME: HACK! 3390 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3391 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3392 3393 assert((NewFD->isInvalidDecl() || !Redeclaration || 3394 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3395 "previous declaration set still overloaded"); 3396 3397 NamedDecl *PrincipalDecl = (FunctionTemplate 3398 ? cast<NamedDecl>(FunctionTemplate) 3399 : NewFD); 3400 3401 if (isFriend && Redeclaration) { 3402 AccessSpecifier Access = AS_public; 3403 if (!NewFD->isInvalidDecl()) 3404 Access = NewFD->getPreviousDeclaration()->getAccess(); 3405 3406 NewFD->setAccess(Access); 3407 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3408 3409 PrincipalDecl->setObjectOfFriendDecl(true); 3410 } 3411 3412 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3413 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3414 PrincipalDecl->setNonMemberOperator(); 3415 3416 // If we have a function template, check the template parameter 3417 // list. This will check and merge default template arguments. 3418 if (FunctionTemplate) { 3419 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3420 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3421 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3422 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3423 : TPC_FunctionTemplate); 3424 } 3425 3426 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3427 // Fake up an access specifier if it's supposed to be a class member. 3428 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3429 NewFD->setAccess(AS_public); 3430 3431 // An out-of-line member function declaration must also be a 3432 // definition (C++ [dcl.meaning]p1). 3433 // Note that this is not the case for explicit specializations of 3434 // function templates or member functions of class templates, per 3435 // C++ [temp.expl.spec]p2. 3436 if (!IsFunctionDefinition && !isFriend && 3437 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3438 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3439 << D.getCXXScopeSpec().getRange(); 3440 NewFD->setInvalidDecl(); 3441 } else if (!Redeclaration && 3442 !(isFriend && CurContext->isDependentContext())) { 3443 // The user tried to provide an out-of-line definition for a 3444 // function that is a member of a class or namespace, but there 3445 // was no such member function declared (C++ [class.mfct]p2, 3446 // C++ [namespace.memdef]p2). For example: 3447 // 3448 // class X { 3449 // void f() const; 3450 // }; 3451 // 3452 // void X::f() { } // ill-formed 3453 // 3454 // Complain about this problem, and attempt to suggest close 3455 // matches (e.g., those that differ only in cv-qualifiers and 3456 // whether the parameter types are references). 3457 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3458 << Name << DC << D.getCXXScopeSpec().getRange(); 3459 NewFD->setInvalidDecl(); 3460 3461 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3462 ForRedeclaration); 3463 LookupQualifiedName(Prev, DC); 3464 assert(!Prev.isAmbiguous() && 3465 "Cannot have an ambiguity in previous-declaration lookup"); 3466 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3467 Func != FuncEnd; ++Func) { 3468 if (isa<FunctionDecl>(*Func) && 3469 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3470 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3471 } 3472 } 3473 } 3474 3475 // Handle attributes. We need to have merged decls when handling attributes 3476 // (for example to check for conflicts, etc). 3477 // FIXME: This needs to happen before we merge declarations. Then, 3478 // let attribute merging cope with attribute conflicts. 3479 ProcessDeclAttributes(S, NewFD, D); 3480 3481 // attributes declared post-definition are currently ignored 3482 if (Redeclaration && Previous.isSingleResult()) { 3483 const FunctionDecl *Def; 3484 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3485 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3486 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3487 Diag(Def->getLocation(), diag::note_previous_definition); 3488 } 3489 } 3490 3491 AddKnownFunctionAttributes(NewFD); 3492 3493 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3494 // If a function name is overloadable in C, then every function 3495 // with that name must be marked "overloadable". 3496 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3497 << Redeclaration << NewFD; 3498 if (!Previous.empty()) 3499 Diag(Previous.getRepresentativeDecl()->getLocation(), 3500 diag::note_attribute_overloadable_prev_overload); 3501 NewFD->addAttr(::new (Context) OverloadableAttr()); 3502 } 3503 3504 // If this is a locally-scoped extern C function, update the 3505 // map of such names. 3506 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3507 && !NewFD->isInvalidDecl()) 3508 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3509 3510 // Set this FunctionDecl's range up to the right paren. 3511 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3512 3513 if (FunctionTemplate && NewFD->isInvalidDecl()) 3514 FunctionTemplate->setInvalidDecl(); 3515 3516 if (FunctionTemplate) 3517 return FunctionTemplate; 3518 3519 3520 // Keep track of static, non-inlined function definitions that 3521 // have not been used. We will warn later. 3522 // FIXME: Also include static functions declared but not defined. 3523 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3524 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3525 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3526 && !NewFD->hasAttr<ConstructorAttr>() 3527 && !NewFD->hasAttr<DestructorAttr>()) 3528 UnusedStaticFuncs.push_back(NewFD); 3529 3530 return NewFD; 3531} 3532 3533/// \brief Perform semantic checking of a new function declaration. 3534/// 3535/// Performs semantic analysis of the new function declaration 3536/// NewFD. This routine performs all semantic checking that does not 3537/// require the actual declarator involved in the declaration, and is 3538/// used both for the declaration of functions as they are parsed 3539/// (called via ActOnDeclarator) and for the declaration of functions 3540/// that have been instantiated via C++ template instantiation (called 3541/// via InstantiateDecl). 3542/// 3543/// \param IsExplicitSpecialiation whether this new function declaration is 3544/// an explicit specialization of the previous declaration. 3545/// 3546/// This sets NewFD->isInvalidDecl() to true if there was an error. 3547void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3548 LookupResult &Previous, 3549 bool IsExplicitSpecialization, 3550 bool &Redeclaration, 3551 bool &OverloadableAttrRequired) { 3552 // If NewFD is already known erroneous, don't do any of this checking. 3553 if (NewFD->isInvalidDecl()) 3554 return; 3555 3556 if (NewFD->getResultType()->isVariablyModifiedType()) { 3557 // Functions returning a variably modified type violate C99 6.7.5.2p2 3558 // because all functions have linkage. 3559 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3560 return NewFD->setInvalidDecl(); 3561 } 3562 3563 if (NewFD->isMain()) 3564 CheckMain(NewFD); 3565 3566 // Check for a previous declaration of this name. 3567 if (Previous.empty() && NewFD->isExternC()) { 3568 // Since we did not find anything by this name and we're declaring 3569 // an extern "C" function, look for a non-visible extern "C" 3570 // declaration with the same name. 3571 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3572 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3573 if (Pos != LocallyScopedExternalDecls.end()) 3574 Previous.addDecl(Pos->second); 3575 } 3576 3577 // Merge or overload the declaration with an existing declaration of 3578 // the same name, if appropriate. 3579 if (!Previous.empty()) { 3580 // Determine whether NewFD is an overload of PrevDecl or 3581 // a declaration that requires merging. If it's an overload, 3582 // there's no more work to do here; we'll just add the new 3583 // function to the scope. 3584 3585 NamedDecl *OldDecl = 0; 3586 if (!AllowOverloadingOfFunction(Previous, Context)) { 3587 Redeclaration = true; 3588 OldDecl = Previous.getFoundDecl(); 3589 } else { 3590 if (!getLangOptions().CPlusPlus) { 3591 OverloadableAttrRequired = true; 3592 3593 // Functions marked "overloadable" must have a prototype (that 3594 // we can't get through declaration merging). 3595 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3596 Diag(NewFD->getLocation(), 3597 diag::err_attribute_overloadable_no_prototype) 3598 << NewFD; 3599 Redeclaration = true; 3600 3601 // Turn this into a variadic function with no parameters. 3602 QualType R = Context.getFunctionType( 3603 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3604 0, 0, true, 0, false, false, 0, 0, 3605 FunctionType::ExtInfo()); 3606 NewFD->setType(R); 3607 return NewFD->setInvalidDecl(); 3608 } 3609 } 3610 3611 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3612 /*NewIsUsingDecl*/ false)) { 3613 case Ovl_Match: 3614 Redeclaration = true; 3615 break; 3616 3617 case Ovl_NonFunction: 3618 Redeclaration = true; 3619 break; 3620 3621 case Ovl_Overload: 3622 Redeclaration = false; 3623 break; 3624 } 3625 } 3626 3627 if (Redeclaration) { 3628 // NewFD and OldDecl represent declarations that need to be 3629 // merged. 3630 if (MergeFunctionDecl(NewFD, OldDecl)) 3631 return NewFD->setInvalidDecl(); 3632 3633 Previous.clear(); 3634 Previous.addDecl(OldDecl); 3635 3636 if (FunctionTemplateDecl *OldTemplateDecl 3637 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3638 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3639 FunctionTemplateDecl *NewTemplateDecl 3640 = NewFD->getDescribedFunctionTemplate(); 3641 assert(NewTemplateDecl && "Template/non-template mismatch"); 3642 if (CXXMethodDecl *Method 3643 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3644 Method->setAccess(OldTemplateDecl->getAccess()); 3645 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3646 } 3647 3648 // If this is an explicit specialization of a member that is a function 3649 // template, mark it as a member specialization. 3650 if (IsExplicitSpecialization && 3651 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3652 NewTemplateDecl->setMemberSpecialization(); 3653 assert(OldTemplateDecl->isMemberSpecialization()); 3654 } 3655 } else { 3656 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3657 NewFD->setAccess(OldDecl->getAccess()); 3658 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3659 } 3660 } 3661 } 3662 3663 // Semantic checking for this function declaration (in isolation). 3664 if (getLangOptions().CPlusPlus) { 3665 // C++-specific checks. 3666 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3667 CheckConstructor(Constructor); 3668 } else if (CXXDestructorDecl *Destructor = 3669 dyn_cast<CXXDestructorDecl>(NewFD)) { 3670 CXXRecordDecl *Record = Destructor->getParent(); 3671 QualType ClassType = Context.getTypeDeclType(Record); 3672 3673 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3674 // type is dependent? Both gcc and edg can handle that. 3675 if (!ClassType->isDependentType()) { 3676 DeclarationName Name 3677 = Context.DeclarationNames.getCXXDestructorName( 3678 Context.getCanonicalType(ClassType)); 3679 if (NewFD->getDeclName() != Name) { 3680 Diag(NewFD->getLocation(), diag::err_destructor_name); 3681 return NewFD->setInvalidDecl(); 3682 } 3683 } 3684 3685 Record->setUserDeclaredDestructor(true); 3686 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3687 // user-defined destructor. 3688 Record->setPOD(false); 3689 3690 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3691 // declared destructor. 3692 // FIXME: C++0x: don't do this for "= default" destructors 3693 Record->setHasTrivialDestructor(false); 3694 } else if (CXXConversionDecl *Conversion 3695 = dyn_cast<CXXConversionDecl>(NewFD)) { 3696 ActOnConversionDeclarator(Conversion); 3697 } 3698 3699 // Find any virtual functions that this function overrides. 3700 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3701 if (!Method->isFunctionTemplateSpecialization() && 3702 !Method->getDescribedFunctionTemplate()) 3703 AddOverriddenMethods(Method->getParent(), Method); 3704 } 3705 3706 // Additional checks for the destructor; make sure we do this after we 3707 // figure out whether the destructor is virtual. 3708 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3709 if (!Destructor->getParent()->isDependentType()) 3710 CheckDestructor(Destructor); 3711 3712 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3713 if (NewFD->isOverloadedOperator() && 3714 CheckOverloadedOperatorDeclaration(NewFD)) 3715 return NewFD->setInvalidDecl(); 3716 3717 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3718 if (NewFD->getLiteralIdentifier() && 3719 CheckLiteralOperatorDeclaration(NewFD)) 3720 return NewFD->setInvalidDecl(); 3721 3722 // In C++, check default arguments now that we have merged decls. Unless 3723 // the lexical context is the class, because in this case this is done 3724 // during delayed parsing anyway. 3725 if (!CurContext->isRecord()) 3726 CheckCXXDefaultArguments(NewFD); 3727 } 3728} 3729 3730void Sema::CheckMain(FunctionDecl* FD) { 3731 // C++ [basic.start.main]p3: A program that declares main to be inline 3732 // or static is ill-formed. 3733 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3734 // shall not appear in a declaration of main. 3735 // static main is not an error under C99, but we should warn about it. 3736 bool isInline = FD->isInlineSpecified(); 3737 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3738 if (isInline || isStatic) { 3739 unsigned diagID = diag::warn_unusual_main_decl; 3740 if (isInline || getLangOptions().CPlusPlus) 3741 diagID = diag::err_unusual_main_decl; 3742 3743 int which = isStatic + (isInline << 1) - 1; 3744 Diag(FD->getLocation(), diagID) << which; 3745 } 3746 3747 QualType T = FD->getType(); 3748 assert(T->isFunctionType() && "function decl is not of function type"); 3749 const FunctionType* FT = T->getAs<FunctionType>(); 3750 3751 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3752 // TODO: add a replacement fixit to turn the return type into 'int'. 3753 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3754 FD->setInvalidDecl(true); 3755 } 3756 3757 // Treat protoless main() as nullary. 3758 if (isa<FunctionNoProtoType>(FT)) return; 3759 3760 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3761 unsigned nparams = FTP->getNumArgs(); 3762 assert(FD->getNumParams() == nparams); 3763 3764 bool HasExtraParameters = (nparams > 3); 3765 3766 // Darwin passes an undocumented fourth argument of type char**. If 3767 // other platforms start sprouting these, the logic below will start 3768 // getting shifty. 3769 if (nparams == 4 && 3770 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3771 HasExtraParameters = false; 3772 3773 if (HasExtraParameters) { 3774 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3775 FD->setInvalidDecl(true); 3776 nparams = 3; 3777 } 3778 3779 // FIXME: a lot of the following diagnostics would be improved 3780 // if we had some location information about types. 3781 3782 QualType CharPP = 3783 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3784 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3785 3786 for (unsigned i = 0; i < nparams; ++i) { 3787 QualType AT = FTP->getArgType(i); 3788 3789 bool mismatch = true; 3790 3791 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3792 mismatch = false; 3793 else if (Expected[i] == CharPP) { 3794 // As an extension, the following forms are okay: 3795 // char const ** 3796 // char const * const * 3797 // char * const * 3798 3799 QualifierCollector qs; 3800 const PointerType* PT; 3801 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3802 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3803 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3804 qs.removeConst(); 3805 mismatch = !qs.empty(); 3806 } 3807 } 3808 3809 if (mismatch) { 3810 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3811 // TODO: suggest replacing given type with expected type 3812 FD->setInvalidDecl(true); 3813 } 3814 } 3815 3816 if (nparams == 1 && !FD->isInvalidDecl()) { 3817 Diag(FD->getLocation(), diag::warn_main_one_arg); 3818 } 3819} 3820 3821bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3822 // FIXME: Need strict checking. In C89, we need to check for 3823 // any assignment, increment, decrement, function-calls, or 3824 // commas outside of a sizeof. In C99, it's the same list, 3825 // except that the aforementioned are allowed in unevaluated 3826 // expressions. Everything else falls under the 3827 // "may accept other forms of constant expressions" exception. 3828 // (We never end up here for C++, so the constant expression 3829 // rules there don't matter.) 3830 if (Init->isConstantInitializer(Context)) 3831 return false; 3832 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3833 << Init->getSourceRange(); 3834 return true; 3835} 3836 3837void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3838 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3839} 3840 3841/// AddInitializerToDecl - Adds the initializer Init to the 3842/// declaration dcl. If DirectInit is true, this is C++ direct 3843/// initialization rather than copy initialization. 3844void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3845 Decl *RealDecl = dcl.getAs<Decl>(); 3846 // If there is no declaration, there was an error parsing it. Just ignore 3847 // the initializer. 3848 if (RealDecl == 0) 3849 return; 3850 3851 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3852 // With declarators parsed the way they are, the parser cannot 3853 // distinguish between a normal initializer and a pure-specifier. 3854 // Thus this grotesque test. 3855 IntegerLiteral *IL; 3856 Expr *Init = static_cast<Expr *>(init.get()); 3857 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3858 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3859 CheckPureMethod(Method, Init->getSourceRange()); 3860 else { 3861 Diag(Method->getLocation(), diag::err_member_function_initialization) 3862 << Method->getDeclName() << Init->getSourceRange(); 3863 Method->setInvalidDecl(); 3864 } 3865 return; 3866 } 3867 3868 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3869 if (!VDecl) { 3870 if (getLangOptions().CPlusPlus && 3871 RealDecl->getLexicalDeclContext()->isRecord() && 3872 isa<NamedDecl>(RealDecl)) 3873 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3874 << cast<NamedDecl>(RealDecl)->getDeclName(); 3875 else 3876 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3877 RealDecl->setInvalidDecl(); 3878 return; 3879 } 3880 3881 // A definition must end up with a complete type, which means it must be 3882 // complete with the restriction that an array type might be completed by the 3883 // initializer; note that later code assumes this restriction. 3884 QualType BaseDeclType = VDecl->getType(); 3885 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3886 BaseDeclType = Array->getElementType(); 3887 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3888 diag::err_typecheck_decl_incomplete_type)) { 3889 RealDecl->setInvalidDecl(); 3890 return; 3891 } 3892 3893 // The variable can not have an abstract class type. 3894 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3895 diag::err_abstract_type_in_decl, 3896 AbstractVariableType)) 3897 VDecl->setInvalidDecl(); 3898 3899 const VarDecl *Def; 3900 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3901 Diag(VDecl->getLocation(), diag::err_redefinition) 3902 << VDecl->getDeclName(); 3903 Diag(Def->getLocation(), diag::note_previous_definition); 3904 VDecl->setInvalidDecl(); 3905 return; 3906 } 3907 3908 // Take ownership of the expression, now that we're sure we have somewhere 3909 // to put it. 3910 Expr *Init = init.takeAs<Expr>(); 3911 assert(Init && "missing initializer"); 3912 3913 // Capture the variable that is being initialized and the style of 3914 // initialization. 3915 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3916 3917 // FIXME: Poor source location information. 3918 InitializationKind Kind 3919 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3920 Init->getLocStart(), 3921 Init->getLocEnd()) 3922 : InitializationKind::CreateCopy(VDecl->getLocation(), 3923 Init->getLocStart()); 3924 3925 // Get the decls type and save a reference for later, since 3926 // CheckInitializerTypes may change it. 3927 QualType DclT = VDecl->getType(), SavT = DclT; 3928 if (VDecl->isBlockVarDecl()) { 3929 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3930 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3931 VDecl->setInvalidDecl(); 3932 } else if (!VDecl->isInvalidDecl()) { 3933 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3934 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3935 MultiExprArg(*this, (void**)&Init, 1), 3936 &DclT); 3937 if (Result.isInvalid()) { 3938 VDecl->setInvalidDecl(); 3939 return; 3940 } 3941 3942 Init = Result.takeAs<Expr>(); 3943 3944 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3945 // Don't check invalid declarations to avoid emitting useless diagnostics. 3946 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3947 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3948 CheckForConstantInitializer(Init, DclT); 3949 } 3950 } 3951 } else if (VDecl->isStaticDataMember() && 3952 VDecl->getLexicalDeclContext()->isRecord()) { 3953 // This is an in-class initialization for a static data member, e.g., 3954 // 3955 // struct S { 3956 // static const int value = 17; 3957 // }; 3958 3959 // Attach the initializer 3960 VDecl->setInit(Init); 3961 3962 // C++ [class.mem]p4: 3963 // A member-declarator can contain a constant-initializer only 3964 // if it declares a static member (9.4) of const integral or 3965 // const enumeration type, see 9.4.2. 3966 QualType T = VDecl->getType(); 3967 if (!T->isDependentType() && 3968 (!Context.getCanonicalType(T).isConstQualified() || 3969 !T->isIntegralOrEnumerationType())) { 3970 Diag(VDecl->getLocation(), diag::err_member_initialization) 3971 << VDecl->getDeclName() << Init->getSourceRange(); 3972 VDecl->setInvalidDecl(); 3973 } else { 3974 // C++ [class.static.data]p4: 3975 // If a static data member is of const integral or const 3976 // enumeration type, its declaration in the class definition 3977 // can specify a constant-initializer which shall be an 3978 // integral constant expression (5.19). 3979 if (!Init->isTypeDependent() && 3980 !Init->getType()->isIntegralOrEnumerationType()) { 3981 // We have a non-dependent, non-integral or enumeration type. 3982 Diag(Init->getSourceRange().getBegin(), 3983 diag::err_in_class_initializer_non_integral_type) 3984 << Init->getType() << Init->getSourceRange(); 3985 VDecl->setInvalidDecl(); 3986 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3987 // Check whether the expression is a constant expression. 3988 llvm::APSInt Value; 3989 SourceLocation Loc; 3990 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3991 Diag(Loc, diag::err_in_class_initializer_non_constant) 3992 << Init->getSourceRange(); 3993 VDecl->setInvalidDecl(); 3994 } else if (!VDecl->getType()->isDependentType()) 3995 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3996 } 3997 } 3998 } else if (VDecl->isFileVarDecl()) { 3999 if (VDecl->getStorageClass() == VarDecl::Extern && 4000 (!getLangOptions().CPlusPlus || 4001 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4002 Diag(VDecl->getLocation(), diag::warn_extern_init); 4003 if (!VDecl->isInvalidDecl()) { 4004 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4005 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4006 MultiExprArg(*this, (void**)&Init, 1), 4007 &DclT); 4008 if (Result.isInvalid()) { 4009 VDecl->setInvalidDecl(); 4010 return; 4011 } 4012 4013 Init = Result.takeAs<Expr>(); 4014 } 4015 4016 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4017 // Don't check invalid declarations to avoid emitting useless diagnostics. 4018 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4019 // C99 6.7.8p4. All file scoped initializers need to be constant. 4020 CheckForConstantInitializer(Init, DclT); 4021 } 4022 } 4023 // If the type changed, it means we had an incomplete type that was 4024 // completed by the initializer. For example: 4025 // int ary[] = { 1, 3, 5 }; 4026 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4027 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4028 VDecl->setType(DclT); 4029 Init->setType(DclT); 4030 } 4031 4032 Init = MaybeCreateCXXExprWithTemporaries(Init); 4033 // Attach the initializer to the decl. 4034 VDecl->setInit(Init); 4035 4036 if (getLangOptions().CPlusPlus) { 4037 // Make sure we mark the destructor as used if necessary. 4038 QualType InitType = VDecl->getType(); 4039 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4040 InitType = Context.getBaseElementType(Array); 4041 if (const RecordType *Record = InitType->getAs<RecordType>()) 4042 FinalizeVarWithDestructor(VDecl, Record); 4043 } 4044 4045 return; 4046} 4047 4048/// ActOnInitializerError - Given that there was an error parsing an 4049/// initializer for the given declaration, try to return to some form 4050/// of sanity. 4051void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4052 // Our main concern here is re-establishing invariants like "a 4053 // variable's type is either dependent or complete". 4054 Decl *D = dcl.getAs<Decl>(); 4055 if (!D || D->isInvalidDecl()) return; 4056 4057 VarDecl *VD = dyn_cast<VarDecl>(D); 4058 if (!VD) return; 4059 4060 QualType Ty = VD->getType(); 4061 if (Ty->isDependentType()) return; 4062 4063 // Require a complete type. 4064 if (RequireCompleteType(VD->getLocation(), 4065 Context.getBaseElementType(Ty), 4066 diag::err_typecheck_decl_incomplete_type)) { 4067 VD->setInvalidDecl(); 4068 return; 4069 } 4070 4071 // Require an abstract type. 4072 if (RequireNonAbstractType(VD->getLocation(), Ty, 4073 diag::err_abstract_type_in_decl, 4074 AbstractVariableType)) { 4075 VD->setInvalidDecl(); 4076 return; 4077 } 4078 4079 // Don't bother complaining about constructors or destructors, 4080 // though. 4081} 4082 4083void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4084 bool TypeContainsUndeducedAuto) { 4085 Decl *RealDecl = dcl.getAs<Decl>(); 4086 4087 // If there is no declaration, there was an error parsing it. Just ignore it. 4088 if (RealDecl == 0) 4089 return; 4090 4091 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4092 QualType Type = Var->getType(); 4093 4094 // C++0x [dcl.spec.auto]p3 4095 if (TypeContainsUndeducedAuto) { 4096 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4097 << Var->getDeclName() << Type; 4098 Var->setInvalidDecl(); 4099 return; 4100 } 4101 4102 switch (Var->isThisDeclarationADefinition()) { 4103 case VarDecl::Definition: 4104 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4105 break; 4106 4107 // We have an out-of-line definition of a static data member 4108 // that has an in-class initializer, so we type-check this like 4109 // a declaration. 4110 // 4111 // Fall through 4112 4113 case VarDecl::DeclarationOnly: 4114 // It's only a declaration. 4115 4116 // Block scope. C99 6.7p7: If an identifier for an object is 4117 // declared with no linkage (C99 6.2.2p6), the type for the 4118 // object shall be complete. 4119 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4120 !Var->getLinkage() && !Var->isInvalidDecl() && 4121 RequireCompleteType(Var->getLocation(), Type, 4122 diag::err_typecheck_decl_incomplete_type)) 4123 Var->setInvalidDecl(); 4124 4125 // Make sure that the type is not abstract. 4126 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4127 RequireNonAbstractType(Var->getLocation(), Type, 4128 diag::err_abstract_type_in_decl, 4129 AbstractVariableType)) 4130 Var->setInvalidDecl(); 4131 return; 4132 4133 case VarDecl::TentativeDefinition: 4134 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4135 // object that has file scope without an initializer, and without a 4136 // storage-class specifier or with the storage-class specifier "static", 4137 // constitutes a tentative definition. Note: A tentative definition with 4138 // external linkage is valid (C99 6.2.2p5). 4139 if (!Var->isInvalidDecl()) { 4140 if (const IncompleteArrayType *ArrayT 4141 = Context.getAsIncompleteArrayType(Type)) { 4142 if (RequireCompleteType(Var->getLocation(), 4143 ArrayT->getElementType(), 4144 diag::err_illegal_decl_array_incomplete_type)) 4145 Var->setInvalidDecl(); 4146 } else if (Var->getStorageClass() == VarDecl::Static) { 4147 // C99 6.9.2p3: If the declaration of an identifier for an object is 4148 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4149 // declared type shall not be an incomplete type. 4150 // NOTE: code such as the following 4151 // static struct s; 4152 // struct s { int a; }; 4153 // is accepted by gcc. Hence here we issue a warning instead of 4154 // an error and we do not invalidate the static declaration. 4155 // NOTE: to avoid multiple warnings, only check the first declaration. 4156 if (Var->getPreviousDeclaration() == 0) 4157 RequireCompleteType(Var->getLocation(), Type, 4158 diag::ext_typecheck_decl_incomplete_type); 4159 } 4160 } 4161 4162 // Record the tentative definition; we're done. 4163 if (!Var->isInvalidDecl()) 4164 TentativeDefinitions.push_back(Var); 4165 return; 4166 } 4167 4168 // Provide a specific diagnostic for uninitialized variable 4169 // definitions with incomplete array type. 4170 if (Type->isIncompleteArrayType()) { 4171 Diag(Var->getLocation(), 4172 diag::err_typecheck_incomplete_array_needs_initializer); 4173 Var->setInvalidDecl(); 4174 return; 4175 } 4176 4177 // Provide a specific diagnostic for uninitialized variable 4178 // definitions with reference type. 4179 if (Type->isReferenceType()) { 4180 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4181 << Var->getDeclName() 4182 << SourceRange(Var->getLocation(), Var->getLocation()); 4183 Var->setInvalidDecl(); 4184 return; 4185 } 4186 4187 // Do not attempt to type-check the default initializer for a 4188 // variable with dependent type. 4189 if (Type->isDependentType()) 4190 return; 4191 4192 if (Var->isInvalidDecl()) 4193 return; 4194 4195 if (RequireCompleteType(Var->getLocation(), 4196 Context.getBaseElementType(Type), 4197 diag::err_typecheck_decl_incomplete_type)) { 4198 Var->setInvalidDecl(); 4199 return; 4200 } 4201 4202 // The variable can not have an abstract class type. 4203 if (RequireNonAbstractType(Var->getLocation(), Type, 4204 diag::err_abstract_type_in_decl, 4205 AbstractVariableType)) { 4206 Var->setInvalidDecl(); 4207 return; 4208 } 4209 4210 const RecordType *Record 4211 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4212 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4213 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4214 // C++03 [dcl.init]p9: 4215 // If no initializer is specified for an object, and the 4216 // object is of (possibly cv-qualified) non-POD class type (or 4217 // array thereof), the object shall be default-initialized; if 4218 // the object is of const-qualified type, the underlying class 4219 // type shall have a user-declared default 4220 // constructor. Otherwise, if no initializer is specified for 4221 // a non- static object, the object and its subobjects, if 4222 // any, have an indeterminate initial value); if the object 4223 // or any of its subobjects are of const-qualified type, the 4224 // program is ill-formed. 4225 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4226 } else { 4227 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4228 InitializationKind Kind 4229 = InitializationKind::CreateDefault(Var->getLocation()); 4230 4231 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4232 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4233 MultiExprArg(*this, 0, 0)); 4234 if (Init.isInvalid()) 4235 Var->setInvalidDecl(); 4236 else if (Init.get()) 4237 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4238 } 4239 4240 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4241 FinalizeVarWithDestructor(Var, Record); 4242 } 4243} 4244 4245Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4246 DeclPtrTy *Group, 4247 unsigned NumDecls) { 4248 llvm::SmallVector<Decl*, 8> Decls; 4249 4250 if (DS.isTypeSpecOwned()) 4251 Decls.push_back((Decl*)DS.getTypeRep()); 4252 4253 for (unsigned i = 0; i != NumDecls; ++i) 4254 if (Decl *D = Group[i].getAs<Decl>()) 4255 Decls.push_back(D); 4256 4257 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4258 Decls.data(), Decls.size())); 4259} 4260 4261 4262/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4263/// to introduce parameters into function prototype scope. 4264Sema::DeclPtrTy 4265Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4266 const DeclSpec &DS = D.getDeclSpec(); 4267 4268 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4269 VarDecl::StorageClass StorageClass = VarDecl::None; 4270 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4271 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4272 StorageClass = VarDecl::Register; 4273 StorageClassAsWritten = VarDecl::Register; 4274 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4275 Diag(DS.getStorageClassSpecLoc(), 4276 diag::err_invalid_storage_class_in_func_decl); 4277 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4278 } 4279 4280 if (D.getDeclSpec().isThreadSpecified()) 4281 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4282 4283 DiagnoseFunctionSpecifiers(D); 4284 4285 // Check that there are no default arguments inside the type of this 4286 // parameter (C++ only). 4287 if (getLangOptions().CPlusPlus) 4288 CheckExtraCXXDefaultArguments(D); 4289 4290 TagDecl *OwnedDecl = 0; 4291 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4292 QualType parmDeclType = TInfo->getType(); 4293 4294 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4295 // C++ [dcl.fct]p6: 4296 // Types shall not be defined in return or parameter types. 4297 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4298 << Context.getTypeDeclType(OwnedDecl); 4299 } 4300 4301 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4302 IdentifierInfo *II = D.getIdentifier(); 4303 if (II) { 4304 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4305 ForRedeclaration); 4306 LookupName(R, S); 4307 if (R.isSingleResult()) { 4308 NamedDecl *PrevDecl = R.getFoundDecl(); 4309 if (PrevDecl->isTemplateParameter()) { 4310 // Maybe we will complain about the shadowed template parameter. 4311 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4312 // Just pretend that we didn't see the previous declaration. 4313 PrevDecl = 0; 4314 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4315 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4316 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4317 4318 // Recover by removing the name 4319 II = 0; 4320 D.SetIdentifier(0, D.getIdentifierLoc()); 4321 D.setInvalidType(true); 4322 } 4323 } 4324 } 4325 4326 // Temporarily put parameter variables in the translation unit, not 4327 // the enclosing context. This prevents them from accidentally 4328 // looking like class members in C++. 4329 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4330 TInfo, parmDeclType, II, 4331 D.getIdentifierLoc(), 4332 StorageClass, StorageClassAsWritten); 4333 4334 if (D.isInvalidType()) 4335 New->setInvalidDecl(); 4336 4337 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4338 if (D.getCXXScopeSpec().isSet()) { 4339 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4340 << D.getCXXScopeSpec().getRange(); 4341 New->setInvalidDecl(); 4342 } 4343 4344 // Add the parameter declaration into this scope. 4345 S->AddDecl(DeclPtrTy::make(New)); 4346 if (II) 4347 IdResolver.AddDecl(New); 4348 4349 ProcessDeclAttributes(S, New, D); 4350 4351 if (New->hasAttr<BlocksAttr>()) { 4352 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4353 } 4354 return DeclPtrTy::make(New); 4355} 4356 4357/// \brief Synthesizes a variable for a parameter arising from a 4358/// typedef. 4359ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4360 SourceLocation Loc, 4361 QualType T) { 4362 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4363 T, Context.getTrivialTypeSourceInfo(T, Loc), 4364 VarDecl::None, VarDecl::None, 0); 4365 Param->setImplicit(); 4366 return Param; 4367} 4368 4369ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4370 TypeSourceInfo *TSInfo, QualType T, 4371 IdentifierInfo *Name, 4372 SourceLocation NameLoc, 4373 VarDecl::StorageClass StorageClass, 4374 VarDecl::StorageClass StorageClassAsWritten) { 4375 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4376 adjustParameterType(T), TSInfo, 4377 StorageClass, StorageClassAsWritten, 4378 0); 4379 4380 // Parameters can not be abstract class types. 4381 // For record types, this is done by the AbstractClassUsageDiagnoser once 4382 // the class has been completely parsed. 4383 if (!CurContext->isRecord() && 4384 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4385 AbstractParamType)) 4386 New->setInvalidDecl(); 4387 4388 // Parameter declarators cannot be interface types. All ObjC objects are 4389 // passed by reference. 4390 if (T->isObjCObjectType()) { 4391 Diag(NameLoc, 4392 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4393 New->setInvalidDecl(); 4394 } 4395 4396 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4397 // duration shall not be qualified by an address-space qualifier." 4398 // Since all parameters have automatic store duration, they can not have 4399 // an address space. 4400 if (T.getAddressSpace() != 0) { 4401 Diag(NameLoc, diag::err_arg_with_address_space); 4402 New->setInvalidDecl(); 4403 } 4404 4405 return New; 4406} 4407 4408void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4409 SourceLocation LocAfterDecls) { 4410 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4411 "Not a function declarator!"); 4412 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4413 4414 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4415 // for a K&R function. 4416 if (!FTI.hasPrototype) { 4417 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4418 --i; 4419 if (FTI.ArgInfo[i].Param == 0) { 4420 llvm::SmallString<256> Code; 4421 llvm::raw_svector_ostream(Code) << " int " 4422 << FTI.ArgInfo[i].Ident->getName() 4423 << ";\n"; 4424 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4425 << FTI.ArgInfo[i].Ident 4426 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4427 4428 // Implicitly declare the argument as type 'int' for lack of a better 4429 // type. 4430 DeclSpec DS; 4431 const char* PrevSpec; // unused 4432 unsigned DiagID; // unused 4433 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4434 PrevSpec, DiagID); 4435 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4436 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4437 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4438 } 4439 } 4440 } 4441} 4442 4443Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4444 Declarator &D) { 4445 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4446 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4447 "Not a function declarator!"); 4448 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4449 4450 if (FTI.hasPrototype) { 4451 // FIXME: Diagnose arguments without names in C. 4452 } 4453 4454 Scope *ParentScope = FnBodyScope->getParent(); 4455 4456 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4457 MultiTemplateParamsArg(*this), 4458 /*IsFunctionDefinition=*/true); 4459 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4460} 4461 4462static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4463 // Don't warn about invalid declarations. 4464 if (FD->isInvalidDecl()) 4465 return false; 4466 4467 // Or declarations that aren't global. 4468 if (!FD->isGlobal()) 4469 return false; 4470 4471 // Don't warn about C++ member functions. 4472 if (isa<CXXMethodDecl>(FD)) 4473 return false; 4474 4475 // Don't warn about 'main'. 4476 if (FD->isMain()) 4477 return false; 4478 4479 // Don't warn about inline functions. 4480 if (FD->isInlineSpecified()) 4481 return false; 4482 4483 // Don't warn about function templates. 4484 if (FD->getDescribedFunctionTemplate()) 4485 return false; 4486 4487 // Don't warn about function template specializations. 4488 if (FD->isFunctionTemplateSpecialization()) 4489 return false; 4490 4491 bool MissingPrototype = true; 4492 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4493 Prev; Prev = Prev->getPreviousDeclaration()) { 4494 // Ignore any declarations that occur in function or method 4495 // scope, because they aren't visible from the header. 4496 if (Prev->getDeclContext()->isFunctionOrMethod()) 4497 continue; 4498 4499 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4500 break; 4501 } 4502 4503 return MissingPrototype; 4504} 4505 4506Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4507 // Clear the last template instantiation error context. 4508 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4509 4510 if (!D) 4511 return D; 4512 FunctionDecl *FD = 0; 4513 4514 if (FunctionTemplateDecl *FunTmpl 4515 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4516 FD = FunTmpl->getTemplatedDecl(); 4517 else 4518 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4519 4520 // Enter a new function scope 4521 PushFunctionScope(); 4522 4523 // See if this is a redefinition. 4524 // But don't complain if we're in GNU89 mode and the previous definition 4525 // was an extern inline function. 4526 const FunctionDecl *Definition; 4527 if (FD->getBody(Definition) && 4528 !canRedefineFunction(Definition, getLangOptions())) { 4529 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4530 Diag(Definition->getLocation(), diag::note_previous_definition); 4531 } 4532 4533 // Builtin functions cannot be defined. 4534 if (unsigned BuiltinID = FD->getBuiltinID()) { 4535 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4536 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4537 FD->setInvalidDecl(); 4538 } 4539 } 4540 4541 // The return type of a function definition must be complete 4542 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4543 QualType ResultType = FD->getResultType(); 4544 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4545 !FD->isInvalidDecl() && 4546 RequireCompleteType(FD->getLocation(), ResultType, 4547 diag::err_func_def_incomplete_result)) 4548 FD->setInvalidDecl(); 4549 4550 // GNU warning -Wmissing-prototypes: 4551 // Warn if a global function is defined without a previous 4552 // prototype declaration. This warning is issued even if the 4553 // definition itself provides a prototype. The aim is to detect 4554 // global functions that fail to be declared in header files. 4555 if (ShouldWarnAboutMissingPrototype(FD)) 4556 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4557 4558 if (FnBodyScope) 4559 PushDeclContext(FnBodyScope, FD); 4560 4561 // Check the validity of our function parameters 4562 CheckParmsForFunctionDef(FD); 4563 4564 bool ShouldCheckShadow = 4565 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4566 4567 // Introduce our parameters into the function scope 4568 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4569 ParmVarDecl *Param = FD->getParamDecl(p); 4570 Param->setOwningFunction(FD); 4571 4572 // If this has an identifier, add it to the scope stack. 4573 if (Param->getIdentifier() && FnBodyScope) { 4574 if (ShouldCheckShadow) 4575 CheckShadow(FnBodyScope, Param); 4576 4577 PushOnScopeChains(Param, FnBodyScope); 4578 } 4579 } 4580 4581 // Checking attributes of current function definition 4582 // dllimport attribute. 4583 if (FD->getAttr<DLLImportAttr>() && 4584 (!FD->getAttr<DLLExportAttr>())) { 4585 // dllimport attribute cannot be applied to definition. 4586 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4587 Diag(FD->getLocation(), 4588 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4589 << "dllimport"; 4590 FD->setInvalidDecl(); 4591 return DeclPtrTy::make(FD); 4592 } 4593 4594 // Visual C++ appears to not think this is an issue, so only issue 4595 // a warning when Microsoft extensions are disabled. 4596 if (!LangOpts.Microsoft) { 4597 // If a symbol previously declared dllimport is later defined, the 4598 // attribute is ignored in subsequent references, and a warning is 4599 // emitted. 4600 Diag(FD->getLocation(), 4601 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4602 << FD->getNameAsCString() << "dllimport"; 4603 } 4604 } 4605 return DeclPtrTy::make(FD); 4606} 4607 4608/// \brief Given the set of return statements within a function body, 4609/// compute the variables that are subject to the named return value 4610/// optimization. 4611/// 4612/// Each of the variables that is subject to the named return value 4613/// optimization will be marked as NRVO variables in the AST, and any 4614/// return statement that has a marked NRVO variable as its NRVO candidate can 4615/// use the named return value optimization. 4616/// 4617/// This function applies a very simplistic algorithm for NRVO: if every return 4618/// statement in the function has the same NRVO candidate, that candidate is 4619/// the NRVO variable. 4620/// 4621/// FIXME: Employ a smarter algorithm that accounts for multiple return 4622/// statements and the lifetimes of the NRVO candidates. We should be able to 4623/// find a maximal set of NRVO variables. 4624static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4625 const VarDecl *NRVOCandidate = 0; 4626 for (unsigned I = 0; I != NumReturns; ++I) { 4627 if (!Returns[I]->getNRVOCandidate()) 4628 return; 4629 4630 if (!NRVOCandidate) 4631 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4632 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4633 return; 4634 } 4635 4636 if (NRVOCandidate) 4637 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4638} 4639 4640Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4641 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4642} 4643 4644Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4645 bool IsInstantiation) { 4646 Decl *dcl = D.getAs<Decl>(); 4647 Stmt *Body = BodyArg.takeAs<Stmt>(); 4648 4649 FunctionDecl *FD = 0; 4650 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4651 if (FunTmpl) 4652 FD = FunTmpl->getTemplatedDecl(); 4653 else 4654 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4655 4656 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4657 4658 if (FD) { 4659 FD->setBody(Body); 4660 if (FD->isMain()) { 4661 // C and C++ allow for main to automagically return 0. 4662 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4663 FD->setHasImplicitReturnZero(true); 4664 WP.disableCheckFallThrough(); 4665 } 4666 4667 if (!FD->isInvalidDecl()) { 4668 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4669 4670 // If this is a constructor, we need a vtable. 4671 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4672 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4673 4674 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4675 FunctionScopes.back()->Returns.size()); 4676 } 4677 4678 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4679 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4680 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4681 MD->setBody(Body); 4682 MD->setEndLoc(Body->getLocEnd()); 4683 if (!MD->isInvalidDecl()) 4684 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4685 } else { 4686 Body->Destroy(Context); 4687 return DeclPtrTy(); 4688 } 4689 4690 // Verify and clean out per-function state. 4691 4692 // Check goto/label use. 4693 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4694 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4695 LabelStmt *L = I->second; 4696 4697 // Verify that we have no forward references left. If so, there was a goto 4698 // or address of a label taken, but no definition of it. Label fwd 4699 // definitions are indicated with a null substmt. 4700 if (L->getSubStmt() != 0) 4701 continue; 4702 4703 // Emit error. 4704 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4705 4706 // At this point, we have gotos that use the bogus label. Stitch it into 4707 // the function body so that they aren't leaked and that the AST is well 4708 // formed. 4709 if (Body == 0) { 4710 // The whole function wasn't parsed correctly, just delete this. 4711 L->Destroy(Context); 4712 continue; 4713 } 4714 4715 // Otherwise, the body is valid: we want to stitch the label decl into the 4716 // function somewhere so that it is properly owned and so that the goto 4717 // has a valid target. Do this by creating a new compound stmt with the 4718 // label in it. 4719 4720 // Give the label a sub-statement. 4721 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4722 4723 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4724 cast<CXXTryStmt>(Body)->getTryBlock() : 4725 cast<CompoundStmt>(Body); 4726 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4727 Compound->body_end()); 4728 Elements.push_back(L); 4729 Compound->setStmts(Context, Elements.data(), Elements.size()); 4730 } 4731 4732 if (Body) { 4733 // C++ constructors that have function-try-blocks can't have return 4734 // statements in the handlers of that block. (C++ [except.handle]p14) 4735 // Verify this. 4736 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4737 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4738 4739 // Verify that that gotos and switch cases don't jump into scopes illegally. 4740 // Verify that that gotos and switch cases don't jump into scopes illegally. 4741 if (FunctionNeedsScopeChecking() && 4742 !dcl->isInvalidDecl() && 4743 !hasAnyErrorsInThisFunction()) 4744 DiagnoseInvalidJumps(Body); 4745 4746 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4747 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4748 Destructor->getParent()); 4749 4750 // If any errors have occurred, clear out any temporaries that may have 4751 // been leftover. This ensures that these temporaries won't be picked up for 4752 // deletion in some later function. 4753 if (PP.getDiagnostics().hasErrorOccurred()) 4754 ExprTemporaries.clear(); 4755 else if (!isa<FunctionTemplateDecl>(dcl)) { 4756 // Since the body is valid, issue any analysis-based warnings that are 4757 // enabled. 4758 QualType ResultType; 4759 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4760 ResultType = FD->getResultType(); 4761 } 4762 else { 4763 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4764 ResultType = MD->getResultType(); 4765 } 4766 AnalysisWarnings.IssueWarnings(WP, dcl); 4767 } 4768 4769 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4770 } 4771 4772 if (!IsInstantiation) 4773 PopDeclContext(); 4774 4775 PopFunctionOrBlockScope(); 4776 4777 // If any errors have occurred, clear out any temporaries that may have 4778 // been leftover. This ensures that these temporaries won't be picked up for 4779 // deletion in some later function. 4780 if (getDiagnostics().hasErrorOccurred()) 4781 ExprTemporaries.clear(); 4782 4783 return D; 4784} 4785 4786/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4787/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4788NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4789 IdentifierInfo &II, Scope *S) { 4790 // Before we produce a declaration for an implicitly defined 4791 // function, see whether there was a locally-scoped declaration of 4792 // this name as a function or variable. If so, use that 4793 // (non-visible) declaration, and complain about it. 4794 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4795 = LocallyScopedExternalDecls.find(&II); 4796 if (Pos != LocallyScopedExternalDecls.end()) { 4797 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4798 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4799 return Pos->second; 4800 } 4801 4802 // Extension in C99. Legal in C90, but warn about it. 4803 if (II.getName().startswith("__builtin_")) 4804 Diag(Loc, diag::warn_builtin_unknown) << &II; 4805 else if (getLangOptions().C99) 4806 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4807 else 4808 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4809 4810 // Set a Declarator for the implicit definition: int foo(); 4811 const char *Dummy; 4812 DeclSpec DS; 4813 unsigned DiagID; 4814 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4815 Error = Error; // Silence warning. 4816 assert(!Error && "Error setting up implicit decl!"); 4817 Declarator D(DS, Declarator::BlockContext); 4818 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4819 0, 0, false, SourceLocation(), 4820 false, 0,0,0, Loc, Loc, D), 4821 SourceLocation()); 4822 D.SetIdentifier(&II, Loc); 4823 4824 // Insert this function into translation-unit scope. 4825 4826 DeclContext *PrevDC = CurContext; 4827 CurContext = Context.getTranslationUnitDecl(); 4828 4829 FunctionDecl *FD = 4830 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4831 FD->setImplicit(); 4832 4833 CurContext = PrevDC; 4834 4835 AddKnownFunctionAttributes(FD); 4836 4837 return FD; 4838} 4839 4840/// \brief Adds any function attributes that we know a priori based on 4841/// the declaration of this function. 4842/// 4843/// These attributes can apply both to implicitly-declared builtins 4844/// (like __builtin___printf_chk) or to library-declared functions 4845/// like NSLog or printf. 4846void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4847 if (FD->isInvalidDecl()) 4848 return; 4849 4850 // If this is a built-in function, map its builtin attributes to 4851 // actual attributes. 4852 if (unsigned BuiltinID = FD->getBuiltinID()) { 4853 // Handle printf-formatting attributes. 4854 unsigned FormatIdx; 4855 bool HasVAListArg; 4856 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4857 if (!FD->getAttr<FormatAttr>()) 4858 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4859 HasVAListArg ? 0 : FormatIdx+2)); 4860 } 4861 4862 // Mark const if we don't care about errno and that is the only 4863 // thing preventing the function from being const. This allows 4864 // IRgen to use LLVM intrinsics for such functions. 4865 if (!getLangOptions().MathErrno && 4866 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4867 if (!FD->getAttr<ConstAttr>()) 4868 FD->addAttr(::new (Context) ConstAttr()); 4869 } 4870 4871 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4872 FD->setType(Context.getNoReturnType(FD->getType())); 4873 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4874 FD->addAttr(::new (Context) NoThrowAttr()); 4875 if (Context.BuiltinInfo.isConst(BuiltinID)) 4876 FD->addAttr(::new (Context) ConstAttr()); 4877 } 4878 4879 IdentifierInfo *Name = FD->getIdentifier(); 4880 if (!Name) 4881 return; 4882 if ((!getLangOptions().CPlusPlus && 4883 FD->getDeclContext()->isTranslationUnit()) || 4884 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4885 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4886 LinkageSpecDecl::lang_c)) { 4887 // Okay: this could be a libc/libm/Objective-C function we know 4888 // about. 4889 } else 4890 return; 4891 4892 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4893 // FIXME: NSLog and NSLogv should be target specific 4894 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4895 // FIXME: We known better than our headers. 4896 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4897 } else 4898 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4899 Name->isStr("NSLogv") ? 0 : 2)); 4900 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4901 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4902 // target-specific builtins, perhaps? 4903 if (!FD->getAttr<FormatAttr>()) 4904 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4905 Name->isStr("vasprintf") ? 0 : 3)); 4906 } 4907} 4908 4909TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4910 TypeSourceInfo *TInfo) { 4911 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4912 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4913 4914 if (!TInfo) { 4915 assert(D.isInvalidType() && "no declarator info for valid type"); 4916 TInfo = Context.getTrivialTypeSourceInfo(T); 4917 } 4918 4919 // Scope manipulation handled by caller. 4920 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4921 D.getIdentifierLoc(), 4922 D.getIdentifier(), 4923 TInfo); 4924 4925 if (const TagType *TT = T->getAs<TagType>()) { 4926 TagDecl *TD = TT->getDecl(); 4927 4928 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4929 // keep track of the TypedefDecl. 4930 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4931 TD->setTypedefForAnonDecl(NewTD); 4932 } 4933 4934 if (D.isInvalidType()) 4935 NewTD->setInvalidDecl(); 4936 return NewTD; 4937} 4938 4939 4940/// \brief Determine whether a tag with a given kind is acceptable 4941/// as a redeclaration of the given tag declaration. 4942/// 4943/// \returns true if the new tag kind is acceptable, false otherwise. 4944bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4945 TagTypeKind NewTag, 4946 SourceLocation NewTagLoc, 4947 const IdentifierInfo &Name) { 4948 // C++ [dcl.type.elab]p3: 4949 // The class-key or enum keyword present in the 4950 // elaborated-type-specifier shall agree in kind with the 4951 // declaration to which the name in the elaborated-type-specifier 4952 // refers. This rule also applies to the form of 4953 // elaborated-type-specifier that declares a class-name or 4954 // friend class since it can be construed as referring to the 4955 // definition of the class. Thus, in any 4956 // elaborated-type-specifier, the enum keyword shall be used to 4957 // refer to an enumeration (7.2), the union class-key shall be 4958 // used to refer to a union (clause 9), and either the class or 4959 // struct class-key shall be used to refer to a class (clause 9) 4960 // declared using the class or struct class-key. 4961 TagTypeKind OldTag = Previous->getTagKind(); 4962 if (OldTag == NewTag) 4963 return true; 4964 4965 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 4966 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 4967 // Warn about the struct/class tag mismatch. 4968 bool isTemplate = false; 4969 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4970 isTemplate = Record->getDescribedClassTemplate(); 4971 4972 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4973 << (NewTag == TTK_Class) 4974 << isTemplate << &Name 4975 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 4976 OldTag == TTK_Class? "class" : "struct"); 4977 Diag(Previous->getLocation(), diag::note_previous_use); 4978 return true; 4979 } 4980 return false; 4981} 4982 4983/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4984/// former case, Name will be non-null. In the later case, Name will be null. 4985/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4986/// reference/declaration/definition of a tag. 4987Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4988 SourceLocation KWLoc, CXXScopeSpec &SS, 4989 IdentifierInfo *Name, SourceLocation NameLoc, 4990 AttributeList *Attr, AccessSpecifier AS, 4991 MultiTemplateParamsArg TemplateParameterLists, 4992 bool &OwnedDecl, bool &IsDependent) { 4993 // If this is not a definition, it must have a name. 4994 assert((Name != 0 || TUK == TUK_Definition) && 4995 "Nameless record must be a definition!"); 4996 4997 OwnedDecl = false; 4998 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 4999 5000 // FIXME: Check explicit specializations more carefully. 5001 bool isExplicitSpecialization = false; 5002 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5003 if (TUK != TUK_Reference) { 5004 if (TemplateParameterList *TemplateParams 5005 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5006 (TemplateParameterList**)TemplateParameterLists.get(), 5007 TemplateParameterLists.size(), 5008 TUK == TUK_Friend, 5009 isExplicitSpecialization)) { 5010 // All but one template parameter lists have been matching. 5011 --NumMatchedTemplateParamLists; 5012 5013 if (TemplateParams->size() > 0) { 5014 // This is a declaration or definition of a class template (which may 5015 // be a member of another template). 5016 OwnedDecl = false; 5017 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5018 SS, Name, NameLoc, Attr, 5019 TemplateParams, 5020 AS); 5021 TemplateParameterLists.release(); 5022 return Result.get(); 5023 } else { 5024 // The "template<>" header is extraneous. 5025 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5026 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5027 isExplicitSpecialization = true; 5028 } 5029 } 5030 } 5031 5032 DeclContext *SearchDC = CurContext; 5033 DeclContext *DC = CurContext; 5034 bool isStdBadAlloc = false; 5035 bool Invalid = false; 5036 5037 RedeclarationKind Redecl = ForRedeclaration; 5038 if (TUK == TUK_Friend || TUK == TUK_Reference) 5039 Redecl = NotForRedeclaration; 5040 5041 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5042 5043 if (Name && SS.isNotEmpty()) { 5044 // We have a nested-name tag ('struct foo::bar'). 5045 5046 // Check for invalid 'foo::'. 5047 if (SS.isInvalid()) { 5048 Name = 0; 5049 goto CreateNewDecl; 5050 } 5051 5052 // If this is a friend or a reference to a class in a dependent 5053 // context, don't try to make a decl for it. 5054 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5055 DC = computeDeclContext(SS, false); 5056 if (!DC) { 5057 IsDependent = true; 5058 return DeclPtrTy(); 5059 } 5060 } else { 5061 DC = computeDeclContext(SS, true); 5062 if (!DC) { 5063 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5064 << SS.getRange(); 5065 return DeclPtrTy(); 5066 } 5067 } 5068 5069 if (RequireCompleteDeclContext(SS, DC)) 5070 return DeclPtrTy::make((Decl *)0); 5071 5072 SearchDC = DC; 5073 // Look-up name inside 'foo::'. 5074 LookupQualifiedName(Previous, DC); 5075 5076 if (Previous.isAmbiguous()) 5077 return DeclPtrTy(); 5078 5079 if (Previous.empty()) { 5080 // Name lookup did not find anything. However, if the 5081 // nested-name-specifier refers to the current instantiation, 5082 // and that current instantiation has any dependent base 5083 // classes, we might find something at instantiation time: treat 5084 // this as a dependent elaborated-type-specifier. 5085 if (Previous.wasNotFoundInCurrentInstantiation()) { 5086 IsDependent = true; 5087 return DeclPtrTy(); 5088 } 5089 5090 // A tag 'foo::bar' must already exist. 5091 Diag(NameLoc, diag::err_not_tag_in_scope) 5092 << Kind << Name << DC << SS.getRange(); 5093 Name = 0; 5094 Invalid = true; 5095 goto CreateNewDecl; 5096 } 5097 } else if (Name) { 5098 // If this is a named struct, check to see if there was a previous forward 5099 // declaration or definition. 5100 // FIXME: We're looking into outer scopes here, even when we 5101 // shouldn't be. Doing so can result in ambiguities that we 5102 // shouldn't be diagnosing. 5103 LookupName(Previous, S); 5104 5105 // Note: there used to be some attempt at recovery here. 5106 if (Previous.isAmbiguous()) 5107 return DeclPtrTy(); 5108 5109 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5110 // FIXME: This makes sure that we ignore the contexts associated 5111 // with C structs, unions, and enums when looking for a matching 5112 // tag declaration or definition. See the similar lookup tweak 5113 // in Sema::LookupName; is there a better way to deal with this? 5114 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5115 SearchDC = SearchDC->getParent(); 5116 } 5117 } 5118 5119 if (Previous.isSingleResult() && 5120 Previous.getFoundDecl()->isTemplateParameter()) { 5121 // Maybe we will complain about the shadowed template parameter. 5122 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5123 // Just pretend that we didn't see the previous declaration. 5124 Previous.clear(); 5125 } 5126 5127 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5128 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 5129 // This is a declaration of or a reference to "std::bad_alloc". 5130 isStdBadAlloc = true; 5131 5132 if (Previous.empty() && StdBadAlloc) { 5133 // std::bad_alloc has been implicitly declared (but made invisible to 5134 // name lookup). Fill in this implicit declaration as the previous 5135 // declaration, so that the declarations get chained appropriately. 5136 Previous.addDecl(StdBadAlloc); 5137 } 5138 } 5139 5140 // If we didn't find a previous declaration, and this is a reference 5141 // (or friend reference), move to the correct scope. In C++, we 5142 // also need to do a redeclaration lookup there, just in case 5143 // there's a shadow friend decl. 5144 if (Name && Previous.empty() && 5145 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5146 if (Invalid) goto CreateNewDecl; 5147 assert(SS.isEmpty()); 5148 5149 if (TUK == TUK_Reference) { 5150 // C++ [basic.scope.pdecl]p5: 5151 // -- for an elaborated-type-specifier of the form 5152 // 5153 // class-key identifier 5154 // 5155 // if the elaborated-type-specifier is used in the 5156 // decl-specifier-seq or parameter-declaration-clause of a 5157 // function defined in namespace scope, the identifier is 5158 // declared as a class-name in the namespace that contains 5159 // the declaration; otherwise, except as a friend 5160 // declaration, the identifier is declared in the smallest 5161 // non-class, non-function-prototype scope that contains the 5162 // declaration. 5163 // 5164 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5165 // C structs and unions. 5166 // 5167 // It is an error in C++ to declare (rather than define) an enum 5168 // type, including via an elaborated type specifier. We'll 5169 // diagnose that later; for now, declare the enum in the same 5170 // scope as we would have picked for any other tag type. 5171 // 5172 // GNU C also supports this behavior as part of its incomplete 5173 // enum types extension, while GNU C++ does not. 5174 // 5175 // Find the context where we'll be declaring the tag. 5176 // FIXME: We would like to maintain the current DeclContext as the 5177 // lexical context, 5178 while (SearchDC->isRecord()) 5179 SearchDC = SearchDC->getParent(); 5180 5181 // Find the scope where we'll be declaring the tag. 5182 while (S->isClassScope() || 5183 (getLangOptions().CPlusPlus && 5184 S->isFunctionPrototypeScope()) || 5185 ((S->getFlags() & Scope::DeclScope) == 0) || 5186 (S->getEntity() && 5187 ((DeclContext *)S->getEntity())->isTransparentContext())) 5188 S = S->getParent(); 5189 } else { 5190 assert(TUK == TUK_Friend); 5191 // C++ [namespace.memdef]p3: 5192 // If a friend declaration in a non-local class first declares a 5193 // class or function, the friend class or function is a member of 5194 // the innermost enclosing namespace. 5195 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5196 } 5197 5198 // In C++, we need to do a redeclaration lookup to properly 5199 // diagnose some problems. 5200 if (getLangOptions().CPlusPlus) { 5201 Previous.setRedeclarationKind(ForRedeclaration); 5202 LookupQualifiedName(Previous, SearchDC); 5203 } 5204 } 5205 5206 if (!Previous.empty()) { 5207 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5208 5209 // It's okay to have a tag decl in the same scope as a typedef 5210 // which hides a tag decl in the same scope. Finding this 5211 // insanity with a redeclaration lookup can only actually happen 5212 // in C++. 5213 // 5214 // This is also okay for elaborated-type-specifiers, which is 5215 // technically forbidden by the current standard but which is 5216 // okay according to the likely resolution of an open issue; 5217 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5218 if (getLangOptions().CPlusPlus) { 5219 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5220 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5221 TagDecl *Tag = TT->getDecl(); 5222 if (Tag->getDeclName() == Name && 5223 Tag->getDeclContext()->getLookupContext() 5224 ->Equals(TD->getDeclContext()->getLookupContext())) { 5225 PrevDecl = Tag; 5226 Previous.clear(); 5227 Previous.addDecl(Tag); 5228 } 5229 } 5230 } 5231 } 5232 5233 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5234 // If this is a use of a previous tag, or if the tag is already declared 5235 // in the same scope (so that the definition/declaration completes or 5236 // rementions the tag), reuse the decl. 5237 if (TUK == TUK_Reference || TUK == TUK_Friend || 5238 isDeclInScope(PrevDecl, SearchDC, S)) { 5239 // Make sure that this wasn't declared as an enum and now used as a 5240 // struct or something similar. 5241 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5242 bool SafeToContinue 5243 = (PrevTagDecl->getTagKind() != TTK_Enum && 5244 Kind != TTK_Enum); 5245 if (SafeToContinue) 5246 Diag(KWLoc, diag::err_use_with_wrong_tag) 5247 << Name 5248 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5249 PrevTagDecl->getKindName()); 5250 else 5251 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5252 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5253 5254 if (SafeToContinue) 5255 Kind = PrevTagDecl->getTagKind(); 5256 else { 5257 // Recover by making this an anonymous redefinition. 5258 Name = 0; 5259 Previous.clear(); 5260 Invalid = true; 5261 } 5262 } 5263 5264 if (!Invalid) { 5265 // If this is a use, just return the declaration we found. 5266 5267 // FIXME: In the future, return a variant or some other clue 5268 // for the consumer of this Decl to know it doesn't own it. 5269 // For our current ASTs this shouldn't be a problem, but will 5270 // need to be changed with DeclGroups. 5271 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5272 TUK == TUK_Friend) 5273 return DeclPtrTy::make(PrevTagDecl); 5274 5275 // Diagnose attempts to redefine a tag. 5276 if (TUK == TUK_Definition) { 5277 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5278 // If we're defining a specialization and the previous definition 5279 // is from an implicit instantiation, don't emit an error 5280 // here; we'll catch this in the general case below. 5281 if (!isExplicitSpecialization || 5282 !isa<CXXRecordDecl>(Def) || 5283 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5284 == TSK_ExplicitSpecialization) { 5285 Diag(NameLoc, diag::err_redefinition) << Name; 5286 Diag(Def->getLocation(), diag::note_previous_definition); 5287 // If this is a redefinition, recover by making this 5288 // struct be anonymous, which will make any later 5289 // references get the previous definition. 5290 Name = 0; 5291 Previous.clear(); 5292 Invalid = true; 5293 } 5294 } else { 5295 // If the type is currently being defined, complain 5296 // about a nested redefinition. 5297 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5298 if (Tag->isBeingDefined()) { 5299 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5300 Diag(PrevTagDecl->getLocation(), 5301 diag::note_previous_definition); 5302 Name = 0; 5303 Previous.clear(); 5304 Invalid = true; 5305 } 5306 } 5307 5308 // Okay, this is definition of a previously declared or referenced 5309 // tag PrevDecl. We're going to create a new Decl for it. 5310 } 5311 } 5312 // If we get here we have (another) forward declaration or we 5313 // have a definition. Just create a new decl. 5314 5315 } else { 5316 // If we get here, this is a definition of a new tag type in a nested 5317 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5318 // new decl/type. We set PrevDecl to NULL so that the entities 5319 // have distinct types. 5320 Previous.clear(); 5321 } 5322 // If we get here, we're going to create a new Decl. If PrevDecl 5323 // is non-NULL, it's a definition of the tag declared by 5324 // PrevDecl. If it's NULL, we have a new definition. 5325 5326 5327 // Otherwise, PrevDecl is not a tag, but was found with tag 5328 // lookup. This is only actually possible in C++, where a few 5329 // things like templates still live in the tag namespace. 5330 } else { 5331 assert(getLangOptions().CPlusPlus); 5332 5333 // Use a better diagnostic if an elaborated-type-specifier 5334 // found the wrong kind of type on the first 5335 // (non-redeclaration) lookup. 5336 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5337 !Previous.isForRedeclaration()) { 5338 unsigned Kind = 0; 5339 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5340 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5341 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5342 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5343 Invalid = true; 5344 5345 // Otherwise, only diagnose if the declaration is in scope. 5346 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5347 // do nothing 5348 5349 // Diagnose implicit declarations introduced by elaborated types. 5350 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5351 unsigned Kind = 0; 5352 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5353 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5354 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5355 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5356 Invalid = true; 5357 5358 // Otherwise it's a declaration. Call out a particularly common 5359 // case here. 5360 } else if (isa<TypedefDecl>(PrevDecl)) { 5361 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5362 << Name 5363 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5364 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5365 Invalid = true; 5366 5367 // Otherwise, diagnose. 5368 } else { 5369 // The tag name clashes with something else in the target scope, 5370 // issue an error and recover by making this tag be anonymous. 5371 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5372 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5373 Name = 0; 5374 Invalid = true; 5375 } 5376 5377 // The existing declaration isn't relevant to us; we're in a 5378 // new scope, so clear out the previous declaration. 5379 Previous.clear(); 5380 } 5381 } 5382 5383CreateNewDecl: 5384 5385 TagDecl *PrevDecl = 0; 5386 if (Previous.isSingleResult()) 5387 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5388 5389 // If there is an identifier, use the location of the identifier as the 5390 // location of the decl, otherwise use the location of the struct/union 5391 // keyword. 5392 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5393 5394 // Otherwise, create a new declaration. If there is a previous 5395 // declaration of the same entity, the two will be linked via 5396 // PrevDecl. 5397 TagDecl *New; 5398 5399 if (Kind == TTK_Enum) { 5400 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5401 // enum X { A, B, C } D; D should chain to X. 5402 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5403 cast_or_null<EnumDecl>(PrevDecl)); 5404 // If this is an undefined enum, warn. 5405 if (TUK != TUK_Definition && !Invalid) { 5406 TagDecl *Def; 5407 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5408 Diag(Loc, diag::ext_forward_ref_enum_def) 5409 << New; 5410 Diag(Def->getLocation(), diag::note_previous_definition); 5411 } else { 5412 Diag(Loc, 5413 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5414 : diag::ext_forward_ref_enum); 5415 } 5416 } 5417 } else { 5418 // struct/union/class 5419 5420 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5421 // struct X { int A; } D; D should chain to X. 5422 if (getLangOptions().CPlusPlus) { 5423 // FIXME: Look for a way to use RecordDecl for simple structs. 5424 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5425 cast_or_null<CXXRecordDecl>(PrevDecl)); 5426 5427 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5428 StdBadAlloc = cast<CXXRecordDecl>(New); 5429 } else 5430 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5431 cast_or_null<RecordDecl>(PrevDecl)); 5432 } 5433 5434 // Maybe add qualifier info. 5435 if (SS.isNotEmpty()) { 5436 if (SS.isSet()) { 5437 NestedNameSpecifier *NNS 5438 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5439 New->setQualifierInfo(NNS, SS.getRange()); 5440 if (NumMatchedTemplateParamLists > 0) { 5441 New->setTemplateParameterListsInfo(Context, 5442 NumMatchedTemplateParamLists, 5443 (TemplateParameterList**) TemplateParameterLists.release()); 5444 } 5445 } 5446 else 5447 Invalid = true; 5448 } 5449 5450 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5451 // Add alignment attributes if necessary; these attributes are checked when 5452 // the ASTContext lays out the structure. 5453 // 5454 // It is important for implementing the correct semantics that this 5455 // happen here (in act on tag decl). The #pragma pack stack is 5456 // maintained as a result of parser callbacks which can occur at 5457 // many points during the parsing of a struct declaration (because 5458 // the #pragma tokens are effectively skipped over during the 5459 // parsing of the struct). 5460 AddAlignmentAttributesForRecord(RD); 5461 } 5462 5463 // If this is a specialization of a member class (of a class template), 5464 // check the specialization. 5465 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5466 Invalid = true; 5467 5468 if (Invalid) 5469 New->setInvalidDecl(); 5470 5471 if (Attr) 5472 ProcessDeclAttributeList(S, New, Attr); 5473 5474 // If we're declaring or defining a tag in function prototype scope 5475 // in C, note that this type can only be used within the function. 5476 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5477 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5478 5479 // Set the lexical context. If the tag has a C++ scope specifier, the 5480 // lexical context will be different from the semantic context. 5481 New->setLexicalDeclContext(CurContext); 5482 5483 // Mark this as a friend decl if applicable. 5484 if (TUK == TUK_Friend) 5485 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5486 5487 // Set the access specifier. 5488 if (!Invalid && SearchDC->isRecord()) 5489 SetMemberAccessSpecifier(New, PrevDecl, AS); 5490 5491 if (TUK == TUK_Definition) 5492 New->startDefinition(); 5493 5494 // If this has an identifier, add it to the scope stack. 5495 if (TUK == TUK_Friend) { 5496 // We might be replacing an existing declaration in the lookup tables; 5497 // if so, borrow its access specifier. 5498 if (PrevDecl) 5499 New->setAccess(PrevDecl->getAccess()); 5500 5501 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5502 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5503 if (Name) // can be null along some error paths 5504 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5505 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5506 } else if (Name) { 5507 S = getNonFieldDeclScope(S); 5508 PushOnScopeChains(New, S); 5509 } else { 5510 CurContext->addDecl(New); 5511 } 5512 5513 // If this is the C FILE type, notify the AST context. 5514 if (IdentifierInfo *II = New->getIdentifier()) 5515 if (!New->isInvalidDecl() && 5516 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5517 II->isStr("FILE")) 5518 Context.setFILEDecl(New); 5519 5520 OwnedDecl = true; 5521 return DeclPtrTy::make(New); 5522} 5523 5524void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5525 AdjustDeclIfTemplate(TagD); 5526 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5527 5528 // Enter the tag context. 5529 PushDeclContext(S, Tag); 5530} 5531 5532void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5533 SourceLocation LBraceLoc) { 5534 AdjustDeclIfTemplate(TagD); 5535 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5536 5537 FieldCollector->StartClass(); 5538 5539 if (!Record->getIdentifier()) 5540 return; 5541 5542 // C++ [class]p2: 5543 // [...] The class-name is also inserted into the scope of the 5544 // class itself; this is known as the injected-class-name. For 5545 // purposes of access checking, the injected-class-name is treated 5546 // as if it were a public member name. 5547 CXXRecordDecl *InjectedClassName 5548 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5549 CurContext, Record->getLocation(), 5550 Record->getIdentifier(), 5551 Record->getTagKeywordLoc(), 5552 Record); 5553 InjectedClassName->setImplicit(); 5554 InjectedClassName->setAccess(AS_public); 5555 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5556 InjectedClassName->setDescribedClassTemplate(Template); 5557 PushOnScopeChains(InjectedClassName, S); 5558 assert(InjectedClassName->isInjectedClassName() && 5559 "Broken injected-class-name"); 5560} 5561 5562void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5563 SourceLocation RBraceLoc) { 5564 AdjustDeclIfTemplate(TagD); 5565 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5566 Tag->setRBraceLoc(RBraceLoc); 5567 5568 if (isa<CXXRecordDecl>(Tag)) 5569 FieldCollector->FinishClass(); 5570 5571 // Exit this scope of this tag's definition. 5572 PopDeclContext(); 5573 5574 // Notify the consumer that we've defined a tag. 5575 Consumer.HandleTagDeclDefinition(Tag); 5576} 5577 5578void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5579 AdjustDeclIfTemplate(TagD); 5580 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5581 Tag->setInvalidDecl(); 5582 5583 // We're undoing ActOnTagStartDefinition here, not 5584 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5585 // the FieldCollector. 5586 5587 PopDeclContext(); 5588} 5589 5590// Note that FieldName may be null for anonymous bitfields. 5591bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5592 QualType FieldTy, const Expr *BitWidth, 5593 bool *ZeroWidth) { 5594 // Default to true; that shouldn't confuse checks for emptiness 5595 if (ZeroWidth) 5596 *ZeroWidth = true; 5597 5598 // C99 6.7.2.1p4 - verify the field type. 5599 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5600 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5601 // Handle incomplete types with specific error. 5602 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5603 return true; 5604 if (FieldName) 5605 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5606 << FieldName << FieldTy << BitWidth->getSourceRange(); 5607 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5608 << FieldTy << BitWidth->getSourceRange(); 5609 } 5610 5611 // If the bit-width is type- or value-dependent, don't try to check 5612 // it now. 5613 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5614 return false; 5615 5616 llvm::APSInt Value; 5617 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5618 return true; 5619 5620 if (Value != 0 && ZeroWidth) 5621 *ZeroWidth = false; 5622 5623 // Zero-width bitfield is ok for anonymous field. 5624 if (Value == 0 && FieldName) 5625 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5626 5627 if (Value.isSigned() && Value.isNegative()) { 5628 if (FieldName) 5629 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5630 << FieldName << Value.toString(10); 5631 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5632 << Value.toString(10); 5633 } 5634 5635 if (!FieldTy->isDependentType()) { 5636 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5637 if (Value.getZExtValue() > TypeSize) { 5638 if (!getLangOptions().CPlusPlus) { 5639 if (FieldName) 5640 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5641 << FieldName << (unsigned)Value.getZExtValue() 5642 << (unsigned)TypeSize; 5643 5644 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5645 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5646 } 5647 5648 if (FieldName) 5649 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5650 << FieldName << (unsigned)Value.getZExtValue() 5651 << (unsigned)TypeSize; 5652 else 5653 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5654 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5655 } 5656 } 5657 5658 return false; 5659} 5660 5661/// ActOnField - Each field of a struct/union/class is passed into this in order 5662/// to create a FieldDecl object for it. 5663Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5664 SourceLocation DeclStart, 5665 Declarator &D, ExprTy *BitfieldWidth) { 5666 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5667 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5668 AS_public); 5669 return DeclPtrTy::make(Res); 5670} 5671 5672/// HandleField - Analyze a field of a C struct or a C++ data member. 5673/// 5674FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5675 SourceLocation DeclStart, 5676 Declarator &D, Expr *BitWidth, 5677 AccessSpecifier AS) { 5678 IdentifierInfo *II = D.getIdentifier(); 5679 SourceLocation Loc = DeclStart; 5680 if (II) Loc = D.getIdentifierLoc(); 5681 5682 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5683 QualType T = TInfo->getType(); 5684 if (getLangOptions().CPlusPlus) 5685 CheckExtraCXXDefaultArguments(D); 5686 5687 DiagnoseFunctionSpecifiers(D); 5688 5689 if (D.getDeclSpec().isThreadSpecified()) 5690 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5691 5692 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5693 ForRedeclaration); 5694 5695 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5696 // Maybe we will complain about the shadowed template parameter. 5697 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5698 // Just pretend that we didn't see the previous declaration. 5699 PrevDecl = 0; 5700 } 5701 5702 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5703 PrevDecl = 0; 5704 5705 bool Mutable 5706 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5707 SourceLocation TSSL = D.getSourceRange().getBegin(); 5708 FieldDecl *NewFD 5709 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5710 AS, PrevDecl, &D); 5711 5712 if (NewFD->isInvalidDecl()) 5713 Record->setInvalidDecl(); 5714 5715 if (NewFD->isInvalidDecl() && PrevDecl) { 5716 // Don't introduce NewFD into scope; there's already something 5717 // with the same name in the same scope. 5718 } else if (II) { 5719 PushOnScopeChains(NewFD, S); 5720 } else 5721 Record->addDecl(NewFD); 5722 5723 return NewFD; 5724} 5725 5726/// \brief Build a new FieldDecl and check its well-formedness. 5727/// 5728/// This routine builds a new FieldDecl given the fields name, type, 5729/// record, etc. \p PrevDecl should refer to any previous declaration 5730/// with the same name and in the same scope as the field to be 5731/// created. 5732/// 5733/// \returns a new FieldDecl. 5734/// 5735/// \todo The Declarator argument is a hack. It will be removed once 5736FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5737 TypeSourceInfo *TInfo, 5738 RecordDecl *Record, SourceLocation Loc, 5739 bool Mutable, Expr *BitWidth, 5740 SourceLocation TSSL, 5741 AccessSpecifier AS, NamedDecl *PrevDecl, 5742 Declarator *D) { 5743 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5744 bool InvalidDecl = false; 5745 if (D) InvalidDecl = D->isInvalidType(); 5746 5747 // If we receive a broken type, recover by assuming 'int' and 5748 // marking this declaration as invalid. 5749 if (T.isNull()) { 5750 InvalidDecl = true; 5751 T = Context.IntTy; 5752 } 5753 5754 QualType EltTy = Context.getBaseElementType(T); 5755 if (!EltTy->isDependentType() && 5756 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5757 InvalidDecl = true; 5758 5759 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5760 // than a variably modified type. 5761 if (!InvalidDecl && T->isVariablyModifiedType()) { 5762 bool SizeIsNegative; 5763 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5764 SizeIsNegative); 5765 if (!FixedTy.isNull()) { 5766 Diag(Loc, diag::warn_illegal_constant_array_size); 5767 T = FixedTy; 5768 } else { 5769 if (SizeIsNegative) 5770 Diag(Loc, diag::err_typecheck_negative_array_size); 5771 else 5772 Diag(Loc, diag::err_typecheck_field_variable_size); 5773 InvalidDecl = true; 5774 } 5775 } 5776 5777 // Fields can not have abstract class types 5778 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5779 diag::err_abstract_type_in_decl, 5780 AbstractFieldType)) 5781 InvalidDecl = true; 5782 5783 bool ZeroWidth = false; 5784 // If this is declared as a bit-field, check the bit-field. 5785 if (!InvalidDecl && BitWidth && 5786 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5787 InvalidDecl = true; 5788 DeleteExpr(BitWidth); 5789 BitWidth = 0; 5790 ZeroWidth = false; 5791 } 5792 5793 // Check that 'mutable' is consistent with the type of the declaration. 5794 if (!InvalidDecl && Mutable) { 5795 unsigned DiagID = 0; 5796 if (T->isReferenceType()) 5797 DiagID = diag::err_mutable_reference; 5798 else if (T.isConstQualified()) 5799 DiagID = diag::err_mutable_const; 5800 5801 if (DiagID) { 5802 SourceLocation ErrLoc = Loc; 5803 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 5804 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 5805 Diag(ErrLoc, DiagID); 5806 Mutable = false; 5807 InvalidDecl = true; 5808 } 5809 } 5810 5811 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5812 BitWidth, Mutable); 5813 if (InvalidDecl) 5814 NewFD->setInvalidDecl(); 5815 5816 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5817 Diag(Loc, diag::err_duplicate_member) << II; 5818 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5819 NewFD->setInvalidDecl(); 5820 } 5821 5822 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5823 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5824 5825 if (!T->isPODType()) 5826 CXXRecord->setPOD(false); 5827 if (!ZeroWidth) 5828 CXXRecord->setEmpty(false); 5829 5830 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5831 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5832 if (RDecl->getDefinition()) { 5833 if (!RDecl->hasTrivialConstructor()) 5834 CXXRecord->setHasTrivialConstructor(false); 5835 if (!RDecl->hasTrivialCopyConstructor()) 5836 CXXRecord->setHasTrivialCopyConstructor(false); 5837 if (!RDecl->hasTrivialCopyAssignment()) 5838 CXXRecord->setHasTrivialCopyAssignment(false); 5839 if (!RDecl->hasTrivialDestructor()) 5840 CXXRecord->setHasTrivialDestructor(false); 5841 5842 // C++ 9.5p1: An object of a class with a non-trivial 5843 // constructor, a non-trivial copy constructor, a non-trivial 5844 // destructor, or a non-trivial copy assignment operator 5845 // cannot be a member of a union, nor can an array of such 5846 // objects. 5847 // TODO: C++0x alters this restriction significantly. 5848 if (Record->isUnion()) { 5849 // We check for copy constructors before constructors 5850 // because otherwise we'll never get complaints about 5851 // copy constructors. 5852 5853 CXXSpecialMember member = CXXInvalid; 5854 if (!RDecl->hasTrivialCopyConstructor()) 5855 member = CXXCopyConstructor; 5856 else if (!RDecl->hasTrivialConstructor()) 5857 member = CXXConstructor; 5858 else if (!RDecl->hasTrivialCopyAssignment()) 5859 member = CXXCopyAssignment; 5860 else if (!RDecl->hasTrivialDestructor()) 5861 member = CXXDestructor; 5862 5863 if (member != CXXInvalid) { 5864 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5865 DiagnoseNontrivial(RT, member); 5866 NewFD->setInvalidDecl(); 5867 } 5868 } 5869 } 5870 } 5871 } 5872 5873 // FIXME: We need to pass in the attributes given an AST 5874 // representation, not a parser representation. 5875 if (D) 5876 // FIXME: What to pass instead of TUScope? 5877 ProcessDeclAttributes(TUScope, NewFD, *D); 5878 5879 if (T.isObjCGCWeak()) 5880 Diag(Loc, diag::warn_attribute_weak_on_field); 5881 5882 NewFD->setAccess(AS); 5883 5884 // C++ [dcl.init.aggr]p1: 5885 // An aggregate is an array or a class (clause 9) with [...] no 5886 // private or protected non-static data members (clause 11). 5887 // A POD must be an aggregate. 5888 if (getLangOptions().CPlusPlus && 5889 (AS == AS_private || AS == AS_protected)) { 5890 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5891 CXXRecord->setAggregate(false); 5892 CXXRecord->setPOD(false); 5893 } 5894 5895 return NewFD; 5896} 5897 5898/// DiagnoseNontrivial - Given that a class has a non-trivial 5899/// special member, figure out why. 5900void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5901 QualType QT(T, 0U); 5902 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5903 5904 // Check whether the member was user-declared. 5905 switch (member) { 5906 case CXXInvalid: 5907 break; 5908 5909 case CXXConstructor: 5910 if (RD->hasUserDeclaredConstructor()) { 5911 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5912 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5913 const FunctionDecl *body = 0; 5914 ci->getBody(body); 5915 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5916 SourceLocation CtorLoc = ci->getLocation(); 5917 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5918 return; 5919 } 5920 } 5921 5922 assert(0 && "found no user-declared constructors"); 5923 return; 5924 } 5925 break; 5926 5927 case CXXCopyConstructor: 5928 if (RD->hasUserDeclaredCopyConstructor()) { 5929 SourceLocation CtorLoc = 5930 RD->getCopyConstructor(Context, 0)->getLocation(); 5931 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5932 return; 5933 } 5934 break; 5935 5936 case CXXCopyAssignment: 5937 if (RD->hasUserDeclaredCopyAssignment()) { 5938 // FIXME: this should use the location of the copy 5939 // assignment, not the type. 5940 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5941 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5942 return; 5943 } 5944 break; 5945 5946 case CXXDestructor: 5947 if (RD->hasUserDeclaredDestructor()) { 5948 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5949 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5950 return; 5951 } 5952 break; 5953 } 5954 5955 typedef CXXRecordDecl::base_class_iterator base_iter; 5956 5957 // Virtual bases and members inhibit trivial copying/construction, 5958 // but not trivial destruction. 5959 if (member != CXXDestructor) { 5960 // Check for virtual bases. vbases includes indirect virtual bases, 5961 // so we just iterate through the direct bases. 5962 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5963 if (bi->isVirtual()) { 5964 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5965 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5966 return; 5967 } 5968 5969 // Check for virtual methods. 5970 typedef CXXRecordDecl::method_iterator meth_iter; 5971 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5972 ++mi) { 5973 if (mi->isVirtual()) { 5974 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5975 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5976 return; 5977 } 5978 } 5979 } 5980 5981 bool (CXXRecordDecl::*hasTrivial)() const; 5982 switch (member) { 5983 case CXXConstructor: 5984 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5985 case CXXCopyConstructor: 5986 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5987 case CXXCopyAssignment: 5988 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5989 case CXXDestructor: 5990 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5991 default: 5992 assert(0 && "unexpected special member"); return; 5993 } 5994 5995 // Check for nontrivial bases (and recurse). 5996 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5997 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5998 assert(BaseRT && "Don't know how to handle dependent bases"); 5999 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6000 if (!(BaseRecTy->*hasTrivial)()) { 6001 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6002 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6003 DiagnoseNontrivial(BaseRT, member); 6004 return; 6005 } 6006 } 6007 6008 // Check for nontrivial members (and recurse). 6009 typedef RecordDecl::field_iterator field_iter; 6010 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6011 ++fi) { 6012 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6013 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6014 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6015 6016 if (!(EltRD->*hasTrivial)()) { 6017 SourceLocation FLoc = (*fi)->getLocation(); 6018 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6019 DiagnoseNontrivial(EltRT, member); 6020 return; 6021 } 6022 } 6023 } 6024 6025 assert(0 && "found no explanation for non-trivial member"); 6026} 6027 6028/// TranslateIvarVisibility - Translate visibility from a token ID to an 6029/// AST enum value. 6030static ObjCIvarDecl::AccessControl 6031TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6032 switch (ivarVisibility) { 6033 default: assert(0 && "Unknown visitibility kind"); 6034 case tok::objc_private: return ObjCIvarDecl::Private; 6035 case tok::objc_public: return ObjCIvarDecl::Public; 6036 case tok::objc_protected: return ObjCIvarDecl::Protected; 6037 case tok::objc_package: return ObjCIvarDecl::Package; 6038 } 6039} 6040 6041/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6042/// in order to create an IvarDecl object for it. 6043Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6044 SourceLocation DeclStart, 6045 DeclPtrTy IntfDecl, 6046 Declarator &D, ExprTy *BitfieldWidth, 6047 tok::ObjCKeywordKind Visibility) { 6048 6049 IdentifierInfo *II = D.getIdentifier(); 6050 Expr *BitWidth = (Expr*)BitfieldWidth; 6051 SourceLocation Loc = DeclStart; 6052 if (II) Loc = D.getIdentifierLoc(); 6053 6054 // FIXME: Unnamed fields can be handled in various different ways, for 6055 // example, unnamed unions inject all members into the struct namespace! 6056 6057 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6058 QualType T = TInfo->getType(); 6059 6060 if (BitWidth) { 6061 // 6.7.2.1p3, 6.7.2.1p4 6062 if (VerifyBitField(Loc, II, T, BitWidth)) { 6063 D.setInvalidType(); 6064 DeleteExpr(BitWidth); 6065 BitWidth = 0; 6066 } 6067 } else { 6068 // Not a bitfield. 6069 6070 // validate II. 6071 6072 } 6073 if (T->isReferenceType()) { 6074 Diag(Loc, diag::err_ivar_reference_type); 6075 D.setInvalidType(); 6076 } 6077 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6078 // than a variably modified type. 6079 else if (T->isVariablyModifiedType()) { 6080 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6081 D.setInvalidType(); 6082 } 6083 6084 // Get the visibility (access control) for this ivar. 6085 ObjCIvarDecl::AccessControl ac = 6086 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6087 : ObjCIvarDecl::None; 6088 // Must set ivar's DeclContext to its enclosing interface. 6089 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6090 ObjCContainerDecl *EnclosingContext; 6091 if (ObjCImplementationDecl *IMPDecl = 6092 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6093 // Case of ivar declared in an implementation. Context is that of its class. 6094 EnclosingContext = IMPDecl->getClassInterface(); 6095 assert(EnclosingContext && "Implementation has no class interface!"); 6096 } else { 6097 if (ObjCCategoryDecl *CDecl = 6098 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6099 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6100 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6101 return DeclPtrTy(); 6102 } 6103 } 6104 EnclosingContext = EnclosingDecl; 6105 } 6106 6107 // Construct the decl. 6108 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6109 EnclosingContext, Loc, II, T, 6110 TInfo, ac, (Expr *)BitfieldWidth); 6111 6112 if (II) { 6113 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6114 ForRedeclaration); 6115 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6116 && !isa<TagDecl>(PrevDecl)) { 6117 Diag(Loc, diag::err_duplicate_member) << II; 6118 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6119 NewID->setInvalidDecl(); 6120 } 6121 } 6122 6123 // Process attributes attached to the ivar. 6124 ProcessDeclAttributes(S, NewID, D); 6125 6126 if (D.isInvalidType()) 6127 NewID->setInvalidDecl(); 6128 6129 if (II) { 6130 // FIXME: When interfaces are DeclContexts, we'll need to add 6131 // these to the interface. 6132 S->AddDecl(DeclPtrTy::make(NewID)); 6133 IdResolver.AddDecl(NewID); 6134 } 6135 6136 return DeclPtrTy::make(NewID); 6137} 6138 6139void Sema::ActOnFields(Scope* S, 6140 SourceLocation RecLoc, DeclPtrTy RecDecl, 6141 DeclPtrTy *Fields, unsigned NumFields, 6142 SourceLocation LBrac, SourceLocation RBrac, 6143 AttributeList *Attr) { 6144 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6145 assert(EnclosingDecl && "missing record or interface decl"); 6146 6147 // If the decl this is being inserted into is invalid, then it may be a 6148 // redeclaration or some other bogus case. Don't try to add fields to it. 6149 if (EnclosingDecl->isInvalidDecl()) { 6150 // FIXME: Deallocate fields? 6151 return; 6152 } 6153 6154 6155 // Verify that all the fields are okay. 6156 unsigned NumNamedMembers = 0; 6157 llvm::SmallVector<FieldDecl*, 32> RecFields; 6158 6159 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6160 for (unsigned i = 0; i != NumFields; ++i) { 6161 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6162 6163 // Get the type for the field. 6164 Type *FDTy = FD->getType().getTypePtr(); 6165 6166 if (!FD->isAnonymousStructOrUnion()) { 6167 // Remember all fields written by the user. 6168 RecFields.push_back(FD); 6169 } 6170 6171 // If the field is already invalid for some reason, don't emit more 6172 // diagnostics about it. 6173 if (FD->isInvalidDecl()) { 6174 EnclosingDecl->setInvalidDecl(); 6175 continue; 6176 } 6177 6178 // C99 6.7.2.1p2: 6179 // A structure or union shall not contain a member with 6180 // incomplete or function type (hence, a structure shall not 6181 // contain an instance of itself, but may contain a pointer to 6182 // an instance of itself), except that the last member of a 6183 // structure with more than one named member may have incomplete 6184 // array type; such a structure (and any union containing, 6185 // possibly recursively, a member that is such a structure) 6186 // shall not be a member of a structure or an element of an 6187 // array. 6188 if (FDTy->isFunctionType()) { 6189 // Field declared as a function. 6190 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6191 << FD->getDeclName(); 6192 FD->setInvalidDecl(); 6193 EnclosingDecl->setInvalidDecl(); 6194 continue; 6195 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6196 Record && Record->isStruct()) { 6197 // Flexible array member. 6198 if (NumNamedMembers < 1) { 6199 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6200 << FD->getDeclName(); 6201 FD->setInvalidDecl(); 6202 EnclosingDecl->setInvalidDecl(); 6203 continue; 6204 } 6205 if (!FD->getType()->isDependentType() && 6206 !Context.getBaseElementType(FD->getType())->isPODType()) { 6207 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6208 << FD->getDeclName() << FD->getType(); 6209 FD->setInvalidDecl(); 6210 EnclosingDecl->setInvalidDecl(); 6211 continue; 6212 } 6213 6214 // Okay, we have a legal flexible array member at the end of the struct. 6215 if (Record) 6216 Record->setHasFlexibleArrayMember(true); 6217 } else if (!FDTy->isDependentType() && 6218 RequireCompleteType(FD->getLocation(), FD->getType(), 6219 diag::err_field_incomplete)) { 6220 // Incomplete type 6221 FD->setInvalidDecl(); 6222 EnclosingDecl->setInvalidDecl(); 6223 continue; 6224 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6225 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6226 // If this is a member of a union, then entire union becomes "flexible". 6227 if (Record && Record->isUnion()) { 6228 Record->setHasFlexibleArrayMember(true); 6229 } else { 6230 // If this is a struct/class and this is not the last element, reject 6231 // it. Note that GCC supports variable sized arrays in the middle of 6232 // structures. 6233 if (i != NumFields-1) 6234 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6235 << FD->getDeclName() << FD->getType(); 6236 else { 6237 // We support flexible arrays at the end of structs in 6238 // other structs as an extension. 6239 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6240 << FD->getDeclName(); 6241 if (Record) 6242 Record->setHasFlexibleArrayMember(true); 6243 } 6244 } 6245 } 6246 if (Record && FDTTy->getDecl()->hasObjectMember()) 6247 Record->setHasObjectMember(true); 6248 } else if (FDTy->isObjCObjectType()) { 6249 /// A field cannot be an Objective-c object 6250 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6251 FD->setInvalidDecl(); 6252 EnclosingDecl->setInvalidDecl(); 6253 continue; 6254 } else if (getLangOptions().ObjC1 && 6255 getLangOptions().getGCMode() != LangOptions::NonGC && 6256 Record && 6257 (FD->getType()->isObjCObjectPointerType() || 6258 FD->getType().isObjCGCStrong())) 6259 Record->setHasObjectMember(true); 6260 else if (Context.getAsArrayType(FD->getType())) { 6261 QualType BaseType = Context.getBaseElementType(FD->getType()); 6262 if (Record && BaseType->isRecordType() && 6263 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6264 Record->setHasObjectMember(true); 6265 } 6266 // Keep track of the number of named members. 6267 if (FD->getIdentifier()) 6268 ++NumNamedMembers; 6269 } 6270 6271 // Okay, we successfully defined 'Record'. 6272 if (Record) { 6273 Record->completeDefinition(); 6274 } else { 6275 ObjCIvarDecl **ClsFields = 6276 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6277 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6278 ID->setLocEnd(RBrac); 6279 // Add ivar's to class's DeclContext. 6280 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6281 ClsFields[i]->setLexicalDeclContext(ID); 6282 ID->addDecl(ClsFields[i]); 6283 } 6284 // Must enforce the rule that ivars in the base classes may not be 6285 // duplicates. 6286 if (ID->getSuperClass()) 6287 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6288 } else if (ObjCImplementationDecl *IMPDecl = 6289 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6290 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6291 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6292 // Ivar declared in @implementation never belongs to the implementation. 6293 // Only it is in implementation's lexical context. 6294 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6295 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6296 } else if (ObjCCategoryDecl *CDecl = 6297 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6298 // case of ivars in class extension; all other cases have been 6299 // reported as errors elsewhere. 6300 // FIXME. Class extension does not have a LocEnd field. 6301 // CDecl->setLocEnd(RBrac); 6302 // Add ivar's to class extension's DeclContext. 6303 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6304 ClsFields[i]->setLexicalDeclContext(CDecl); 6305 CDecl->addDecl(ClsFields[i]); 6306 } 6307 } 6308 } 6309 6310 if (Attr) 6311 ProcessDeclAttributeList(S, Record, Attr); 6312} 6313 6314/// \brief Determine whether the given integral value is representable within 6315/// the given type T. 6316static bool isRepresentableIntegerValue(ASTContext &Context, 6317 llvm::APSInt &Value, 6318 QualType T) { 6319 assert(T->isIntegralType(Context) && "Integral type required!"); 6320 unsigned BitWidth = Context.getIntWidth(T); 6321 6322 if (Value.isUnsigned() || Value.isNonNegative()) 6323 return Value.getActiveBits() < BitWidth; 6324 6325 return Value.getMinSignedBits() <= BitWidth; 6326} 6327 6328// \brief Given an integral type, return the next larger integral type 6329// (or a NULL type of no such type exists). 6330static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6331 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6332 // enum checking below. 6333 assert(T->isIntegralType(Context) && "Integral type required!"); 6334 const unsigned NumTypes = 4; 6335 QualType SignedIntegralTypes[NumTypes] = { 6336 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6337 }; 6338 QualType UnsignedIntegralTypes[NumTypes] = { 6339 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6340 Context.UnsignedLongLongTy 6341 }; 6342 6343 unsigned BitWidth = Context.getTypeSize(T); 6344 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6345 : UnsignedIntegralTypes; 6346 for (unsigned I = 0; I != NumTypes; ++I) 6347 if (Context.getTypeSize(Types[I]) > BitWidth) 6348 return Types[I]; 6349 6350 return QualType(); 6351} 6352 6353EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6354 EnumConstantDecl *LastEnumConst, 6355 SourceLocation IdLoc, 6356 IdentifierInfo *Id, 6357 ExprArg val) { 6358 Expr *Val = (Expr *)val.get(); 6359 6360 unsigned IntWidth = Context.Target.getIntWidth(); 6361 llvm::APSInt EnumVal(IntWidth); 6362 QualType EltTy; 6363 if (Val) { 6364 if (Enum->isDependentType() || Val->isTypeDependent()) 6365 EltTy = Context.DependentTy; 6366 else { 6367 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6368 SourceLocation ExpLoc; 6369 if (!Val->isValueDependent() && 6370 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6371 Val = 0; 6372 } else { 6373 if (!getLangOptions().CPlusPlus) { 6374 // C99 6.7.2.2p2: 6375 // The expression that defines the value of an enumeration constant 6376 // shall be an integer constant expression that has a value 6377 // representable as an int. 6378 6379 // Complain if the value is not representable in an int. 6380 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6381 Diag(IdLoc, diag::ext_enum_value_not_int) 6382 << EnumVal.toString(10) << Val->getSourceRange() 6383 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6384 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6385 // Force the type of the expression to 'int'. 6386 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6387 6388 if (Val != val.get()) { 6389 val.release(); 6390 val = Val; 6391 } 6392 } 6393 } 6394 6395 // C++0x [dcl.enum]p5: 6396 // If the underlying type is not fixed, the type of each enumerator 6397 // is the type of its initializing value: 6398 // - If an initializer is specified for an enumerator, the 6399 // initializing value has the same type as the expression. 6400 EltTy = Val->getType(); 6401 } 6402 } 6403 } 6404 6405 if (!Val) { 6406 if (Enum->isDependentType()) 6407 EltTy = Context.DependentTy; 6408 else if (!LastEnumConst) { 6409 // C++0x [dcl.enum]p5: 6410 // If the underlying type is not fixed, the type of each enumerator 6411 // is the type of its initializing value: 6412 // - If no initializer is specified for the first enumerator, the 6413 // initializing value has an unspecified integral type. 6414 // 6415 // GCC uses 'int' for its unspecified integral type, as does 6416 // C99 6.7.2.2p3. 6417 EltTy = Context.IntTy; 6418 } else { 6419 // Assign the last value + 1. 6420 EnumVal = LastEnumConst->getInitVal(); 6421 ++EnumVal; 6422 EltTy = LastEnumConst->getType(); 6423 6424 // Check for overflow on increment. 6425 if (EnumVal < LastEnumConst->getInitVal()) { 6426 // C++0x [dcl.enum]p5: 6427 // If the underlying type is not fixed, the type of each enumerator 6428 // is the type of its initializing value: 6429 // 6430 // - Otherwise the type of the initializing value is the same as 6431 // the type of the initializing value of the preceding enumerator 6432 // unless the incremented value is not representable in that type, 6433 // in which case the type is an unspecified integral type 6434 // sufficient to contain the incremented value. If no such type 6435 // exists, the program is ill-formed. 6436 QualType T = getNextLargerIntegralType(Context, EltTy); 6437 if (T.isNull()) { 6438 // There is no integral type larger enough to represent this 6439 // value. Complain, then allow the value to wrap around. 6440 EnumVal = LastEnumConst->getInitVal(); 6441 EnumVal.zext(EnumVal.getBitWidth() * 2); 6442 Diag(IdLoc, diag::warn_enumerator_too_large) 6443 << EnumVal.toString(10); 6444 } else { 6445 EltTy = T; 6446 } 6447 6448 // Retrieve the last enumerator's value, extent that type to the 6449 // type that is supposed to be large enough to represent the incremented 6450 // value, then increment. 6451 EnumVal = LastEnumConst->getInitVal(); 6452 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6453 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6454 ++EnumVal; 6455 6456 // If we're not in C++, diagnose the overflow of enumerator values, 6457 // which in C99 means that the enumerator value is not representable in 6458 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6459 // permits enumerator values that are representable in some larger 6460 // integral type. 6461 if (!getLangOptions().CPlusPlus && !T.isNull()) 6462 Diag(IdLoc, diag::warn_enum_value_overflow); 6463 } else if (!getLangOptions().CPlusPlus && 6464 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6465 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6466 Diag(IdLoc, diag::ext_enum_value_not_int) 6467 << EnumVal.toString(10) << 1; 6468 } 6469 } 6470 } 6471 6472 if (!EltTy->isDependentType()) { 6473 // Make the enumerator value match the signedness and size of the 6474 // enumerator's type. 6475 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6476 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6477 } 6478 6479 val.release(); 6480 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6481 Val, EnumVal); 6482} 6483 6484 6485Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6486 DeclPtrTy lastEnumConst, 6487 SourceLocation IdLoc, 6488 IdentifierInfo *Id, 6489 SourceLocation EqualLoc, ExprTy *val) { 6490 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6491 EnumConstantDecl *LastEnumConst = 6492 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6493 Expr *Val = static_cast<Expr*>(val); 6494 6495 // The scope passed in may not be a decl scope. Zip up the scope tree until 6496 // we find one that is. 6497 S = getNonFieldDeclScope(S); 6498 6499 // Verify that there isn't already something declared with this name in this 6500 // scope. 6501 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6502 ForRedeclaration); 6503 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6504 // Maybe we will complain about the shadowed template parameter. 6505 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6506 // Just pretend that we didn't see the previous declaration. 6507 PrevDecl = 0; 6508 } 6509 6510 if (PrevDecl) { 6511 // When in C++, we may get a TagDecl with the same name; in this case the 6512 // enum constant will 'hide' the tag. 6513 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6514 "Received TagDecl when not in C++!"); 6515 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6516 if (isa<EnumConstantDecl>(PrevDecl)) 6517 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6518 else 6519 Diag(IdLoc, diag::err_redefinition) << Id; 6520 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6521 if (Val) Val->Destroy(Context); 6522 return DeclPtrTy(); 6523 } 6524 } 6525 6526 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6527 IdLoc, Id, Owned(Val)); 6528 6529 // Register this decl in the current scope stack. 6530 if (New) { 6531 New->setAccess(TheEnumDecl->getAccess()); 6532 PushOnScopeChains(New, S); 6533 } 6534 6535 return DeclPtrTy::make(New); 6536} 6537 6538void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6539 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6540 DeclPtrTy *Elements, unsigned NumElements, 6541 Scope *S, AttributeList *Attr) { 6542 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6543 QualType EnumType = Context.getTypeDeclType(Enum); 6544 6545 if (Attr) 6546 ProcessDeclAttributeList(S, Enum, Attr); 6547 6548 if (Enum->isDependentType()) { 6549 for (unsigned i = 0; i != NumElements; ++i) { 6550 EnumConstantDecl *ECD = 6551 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6552 if (!ECD) continue; 6553 6554 ECD->setType(EnumType); 6555 } 6556 6557 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6558 return; 6559 } 6560 6561 // TODO: If the result value doesn't fit in an int, it must be a long or long 6562 // long value. ISO C does not support this, but GCC does as an extension, 6563 // emit a warning. 6564 unsigned IntWidth = Context.Target.getIntWidth(); 6565 unsigned CharWidth = Context.Target.getCharWidth(); 6566 unsigned ShortWidth = Context.Target.getShortWidth(); 6567 6568 // Verify that all the values are okay, compute the size of the values, and 6569 // reverse the list. 6570 unsigned NumNegativeBits = 0; 6571 unsigned NumPositiveBits = 0; 6572 6573 // Keep track of whether all elements have type int. 6574 bool AllElementsInt = true; 6575 6576 for (unsigned i = 0; i != NumElements; ++i) { 6577 EnumConstantDecl *ECD = 6578 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6579 if (!ECD) continue; // Already issued a diagnostic. 6580 6581 const llvm::APSInt &InitVal = ECD->getInitVal(); 6582 6583 // Keep track of the size of positive and negative values. 6584 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6585 NumPositiveBits = std::max(NumPositiveBits, 6586 (unsigned)InitVal.getActiveBits()); 6587 else 6588 NumNegativeBits = std::max(NumNegativeBits, 6589 (unsigned)InitVal.getMinSignedBits()); 6590 6591 // Keep track of whether every enum element has type int (very commmon). 6592 if (AllElementsInt) 6593 AllElementsInt = ECD->getType() == Context.IntTy; 6594 } 6595 6596 // Figure out the type that should be used for this enum. 6597 // FIXME: Support -fshort-enums. 6598 QualType BestType; 6599 unsigned BestWidth; 6600 6601 // C++0x N3000 [conv.prom]p3: 6602 // An rvalue of an unscoped enumeration type whose underlying 6603 // type is not fixed can be converted to an rvalue of the first 6604 // of the following types that can represent all the values of 6605 // the enumeration: int, unsigned int, long int, unsigned long 6606 // int, long long int, or unsigned long long int. 6607 // C99 6.4.4.3p2: 6608 // An identifier declared as an enumeration constant has type int. 6609 // The C99 rule is modified by a gcc extension 6610 QualType BestPromotionType; 6611 6612 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6613 6614 if (NumNegativeBits) { 6615 // If there is a negative value, figure out the smallest integer type (of 6616 // int/long/longlong) that fits. 6617 // If it's packed, check also if it fits a char or a short. 6618 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6619 BestType = Context.SignedCharTy; 6620 BestWidth = CharWidth; 6621 } else if (Packed && NumNegativeBits <= ShortWidth && 6622 NumPositiveBits < ShortWidth) { 6623 BestType = Context.ShortTy; 6624 BestWidth = ShortWidth; 6625 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6626 BestType = Context.IntTy; 6627 BestWidth = IntWidth; 6628 } else { 6629 BestWidth = Context.Target.getLongWidth(); 6630 6631 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6632 BestType = Context.LongTy; 6633 } else { 6634 BestWidth = Context.Target.getLongLongWidth(); 6635 6636 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6637 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6638 BestType = Context.LongLongTy; 6639 } 6640 } 6641 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6642 } else { 6643 // If there is no negative value, figure out the smallest type that fits 6644 // all of the enumerator values. 6645 // If it's packed, check also if it fits a char or a short. 6646 if (Packed && NumPositiveBits <= CharWidth) { 6647 BestType = Context.UnsignedCharTy; 6648 BestPromotionType = Context.IntTy; 6649 BestWidth = CharWidth; 6650 } else if (Packed && NumPositiveBits <= ShortWidth) { 6651 BestType = Context.UnsignedShortTy; 6652 BestPromotionType = Context.IntTy; 6653 BestWidth = ShortWidth; 6654 } else if (NumPositiveBits <= IntWidth) { 6655 BestType = Context.UnsignedIntTy; 6656 BestWidth = IntWidth; 6657 BestPromotionType 6658 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6659 ? Context.UnsignedIntTy : Context.IntTy; 6660 } else if (NumPositiveBits <= 6661 (BestWidth = Context.Target.getLongWidth())) { 6662 BestType = Context.UnsignedLongTy; 6663 BestPromotionType 6664 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6665 ? Context.UnsignedLongTy : Context.LongTy; 6666 } else { 6667 BestWidth = Context.Target.getLongLongWidth(); 6668 assert(NumPositiveBits <= BestWidth && 6669 "How could an initializer get larger than ULL?"); 6670 BestType = Context.UnsignedLongLongTy; 6671 BestPromotionType 6672 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6673 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6674 } 6675 } 6676 6677 // Loop over all of the enumerator constants, changing their types to match 6678 // the type of the enum if needed. 6679 for (unsigned i = 0; i != NumElements; ++i) { 6680 EnumConstantDecl *ECD = 6681 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6682 if (!ECD) continue; // Already issued a diagnostic. 6683 6684 // Standard C says the enumerators have int type, but we allow, as an 6685 // extension, the enumerators to be larger than int size. If each 6686 // enumerator value fits in an int, type it as an int, otherwise type it the 6687 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6688 // that X has type 'int', not 'unsigned'. 6689 6690 // Determine whether the value fits into an int. 6691 llvm::APSInt InitVal = ECD->getInitVal(); 6692 6693 // If it fits into an integer type, force it. Otherwise force it to match 6694 // the enum decl type. 6695 QualType NewTy; 6696 unsigned NewWidth; 6697 bool NewSign; 6698 if (!getLangOptions().CPlusPlus && 6699 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6700 NewTy = Context.IntTy; 6701 NewWidth = IntWidth; 6702 NewSign = true; 6703 } else if (ECD->getType() == BestType) { 6704 // Already the right type! 6705 if (getLangOptions().CPlusPlus) 6706 // C++ [dcl.enum]p4: Following the closing brace of an 6707 // enum-specifier, each enumerator has the type of its 6708 // enumeration. 6709 ECD->setType(EnumType); 6710 continue; 6711 } else { 6712 NewTy = BestType; 6713 NewWidth = BestWidth; 6714 NewSign = BestType->isSignedIntegerType(); 6715 } 6716 6717 // Adjust the APSInt value. 6718 InitVal.extOrTrunc(NewWidth); 6719 InitVal.setIsSigned(NewSign); 6720 ECD->setInitVal(InitVal); 6721 6722 // Adjust the Expr initializer and type. 6723 if (ECD->getInitExpr()) 6724 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6725 CastExpr::CK_IntegralCast, 6726 ECD->getInitExpr(), 6727 CXXBaseSpecifierArray(), 6728 /*isLvalue=*/false)); 6729 if (getLangOptions().CPlusPlus) 6730 // C++ [dcl.enum]p4: Following the closing brace of an 6731 // enum-specifier, each enumerator has the type of its 6732 // enumeration. 6733 ECD->setType(EnumType); 6734 else 6735 ECD->setType(NewTy); 6736 } 6737 6738 Enum->completeDefinition(BestType, BestPromotionType, 6739 NumPositiveBits, NumNegativeBits); 6740} 6741 6742Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6743 ExprArg expr) { 6744 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6745 6746 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6747 Loc, AsmString); 6748 CurContext->addDecl(New); 6749 return DeclPtrTy::make(New); 6750} 6751 6752void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6753 SourceLocation PragmaLoc, 6754 SourceLocation NameLoc) { 6755 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6756 6757 if (PrevDecl) { 6758 PrevDecl->addAttr(::new (Context) WeakAttr()); 6759 } else { 6760 (void)WeakUndeclaredIdentifiers.insert( 6761 std::pair<IdentifierInfo*,WeakInfo> 6762 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6763 } 6764} 6765 6766void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6767 IdentifierInfo* AliasName, 6768 SourceLocation PragmaLoc, 6769 SourceLocation NameLoc, 6770 SourceLocation AliasNameLoc) { 6771 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6772 LookupOrdinaryName); 6773 WeakInfo W = WeakInfo(Name, NameLoc); 6774 6775 if (PrevDecl) { 6776 if (!PrevDecl->hasAttr<AliasAttr>()) 6777 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6778 DeclApplyPragmaWeak(TUScope, ND, W); 6779 } else { 6780 (void)WeakUndeclaredIdentifiers.insert( 6781 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6782 } 6783} 6784