SemaDecl.cpp revision 697bbe8c8174b8ad339d9ebab8269b2bec930d87
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, so build a 91 // DependentNameType node to describe the type. 92 // FIXME: Record somewhere that this DependentNameType node has no "typename" 93 // keyword associated with it. 94 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 95 II, SS->getRange()).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 102 return 0; 103 } 104 105 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 106 // lookup for class-names. 107 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 108 LookupOrdinaryName; 109 LookupResult Result(*this, &II, NameLoc, Kind); 110 if (LookupCtx) { 111 // Perform "qualified" name lookup into the declaration context we 112 // computed, which is either the type of the base of a member access 113 // expression or the declaration context associated with a prior 114 // nested-name-specifier. 115 LookupQualifiedName(Result, LookupCtx); 116 117 if (ObjectTypePtr && Result.empty()) { 118 // C++ [basic.lookup.classref]p3: 119 // If the unqualified-id is ~type-name, the type-name is looked up 120 // in the context of the entire postfix-expression. If the type T of 121 // the object expression is of a class type C, the type-name is also 122 // looked up in the scope of class C. At least one of the lookups shall 123 // find a name that refers to (possibly cv-qualified) T. 124 LookupName(Result, S); 125 } 126 } else { 127 // Perform unqualified name lookup. 128 LookupName(Result, S); 129 } 130 131 NamedDecl *IIDecl = 0; 132 switch (Result.getResultKind()) { 133 case LookupResult::NotFound: 134 case LookupResult::NotFoundInCurrentInstantiation: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 Result.suppressDiagnostics(); 138 return 0; 139 140 case LookupResult::Ambiguous: 141 // Recover from type-hiding ambiguities by hiding the type. We'll 142 // do the lookup again when looking for an object, and we can 143 // diagnose the error then. If we don't do this, then the error 144 // about hiding the type will be immediately followed by an error 145 // that only makes sense if the identifier was treated like a type. 146 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 147 Result.suppressDiagnostics(); 148 return 0; 149 } 150 151 // Look to see if we have a type anywhere in the list of results. 152 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 153 Res != ResEnd; ++Res) { 154 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 155 if (!IIDecl || 156 (*Res)->getLocation().getRawEncoding() < 157 IIDecl->getLocation().getRawEncoding()) 158 IIDecl = *Res; 159 } 160 } 161 162 if (!IIDecl) { 163 // None of the entities we found is a type, so there is no way 164 // to even assume that the result is a type. In this case, don't 165 // complain about the ambiguity. The parser will either try to 166 // perform this lookup again (e.g., as an object name), which 167 // will produce the ambiguity, or will complain that it expected 168 // a type name. 169 Result.suppressDiagnostics(); 170 return 0; 171 } 172 173 // We found a type within the ambiguous lookup; diagnose the 174 // ambiguity and then return that type. This might be the right 175 // answer, or it might not be, but it suppresses any attempt to 176 // perform the name lookup again. 177 break; 178 179 case LookupResult::Found: 180 IIDecl = Result.getFoundDecl(); 181 break; 182 } 183 184 assert(IIDecl && "Didn't find decl"); 185 186 QualType T; 187 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 188 DiagnoseUseOfDecl(IIDecl, NameLoc); 189 190 if (T.isNull()) 191 T = Context.getTypeDeclType(TD); 192 193 if (SS) 194 T = getQualifiedNameType(*SS, T); 195 196 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 197 T = Context.getObjCInterfaceType(IDecl); 198 } else if (UnresolvedUsingTypenameDecl *UUDecl = 199 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 200 // FIXME: preserve source structure information. 201 T = Context.getDependentNameType(ETK_None, 202 UUDecl->getTargetNestedNameSpecifier(), 203 &II); 204 } else { 205 // If it's not plausibly a type, suppress diagnostics. 206 Result.suppressDiagnostics(); 207 return 0; 208 } 209 210 return T.getAsOpaquePtr(); 211} 212 213/// isTagName() - This method is called *for error recovery purposes only* 214/// to determine if the specified name is a valid tag name ("struct foo"). If 215/// so, this returns the TST for the tag corresponding to it (TST_enum, 216/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 217/// where the user forgot to specify the tag. 218DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 219 // Do a tag name lookup in this scope. 220 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 221 LookupName(R, S, false); 222 R.suppressDiagnostics(); 223 if (R.getResultKind() == LookupResult::Found) 224 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 225 switch (TD->getTagKind()) { 226 case TagDecl::TK_struct: return DeclSpec::TST_struct; 227 case TagDecl::TK_union: return DeclSpec::TST_union; 228 case TagDecl::TK_class: return DeclSpec::TST_class; 229 case TagDecl::TK_enum: return DeclSpec::TST_enum; 230 } 231 } 232 233 return DeclSpec::TST_unspecified; 234} 235 236bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 237 SourceLocation IILoc, 238 Scope *S, 239 CXXScopeSpec *SS, 240 TypeTy *&SuggestedType) { 241 // We don't have anything to suggest (yet). 242 SuggestedType = 0; 243 244 // There may have been a typo in the name of the type. Look up typo 245 // results, in case we have something that we can suggest. 246 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 247 NotForRedeclaration); 248 249 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 250 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 251 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 252 !Result->isInvalidDecl()) { 253 // We found a similarly-named type or interface; suggest that. 254 if (!SS || !SS->isSet()) 255 Diag(IILoc, diag::err_unknown_typename_suggest) 256 << &II << Lookup.getLookupName() 257 << FixItHint::CreateReplacement(SourceRange(IILoc), 258 Result->getNameAsString()); 259 else if (DeclContext *DC = computeDeclContext(*SS, false)) 260 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 261 << &II << DC << Lookup.getLookupName() << SS->getRange() 262 << FixItHint::CreateReplacement(SourceRange(IILoc), 263 Result->getNameAsString()); 264 else 265 llvm_unreachable("could not have corrected a typo here"); 266 267 Diag(Result->getLocation(), diag::note_previous_decl) 268 << Result->getDeclName(); 269 270 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 271 return true; 272 } 273 } else if (Lookup.empty()) { 274 // We corrected to a keyword. 275 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 276 Diag(IILoc, diag::err_unknown_typename_suggest) 277 << &II << Corrected; 278 return true; 279 } 280 } 281 282 if (getLangOptions().CPlusPlus) { 283 // See if II is a class template that the user forgot to pass arguments to. 284 UnqualifiedId Name; 285 Name.setIdentifier(&II, IILoc); 286 CXXScopeSpec EmptySS; 287 TemplateTy TemplateResult; 288 if (isTemplateName(S, SS ? *SS : EmptySS, Name, 0, true, TemplateResult) 289 == TNK_Type_template) { 290 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 291 Diag(IILoc, diag::err_template_missing_args) << TplName; 292 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 293 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 294 << TplDecl->getTemplateParameters()->getSourceRange(); 295 } 296 return true; 297 } 298 } 299 300 // FIXME: Should we move the logic that tries to recover from a missing tag 301 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 302 303 if (!SS || (!SS->isSet() && !SS->isInvalid())) 304 Diag(IILoc, diag::err_unknown_typename) << &II; 305 else if (DeclContext *DC = computeDeclContext(*SS, false)) 306 Diag(IILoc, diag::err_typename_nested_not_found) 307 << &II << DC << SS->getRange(); 308 else if (isDependentScopeSpecifier(*SS)) { 309 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 310 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 311 << SourceRange(SS->getRange().getBegin(), IILoc) 312 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 313 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 314 } else { 315 assert(SS && SS->isInvalid() && 316 "Invalid scope specifier has already been diagnosed"); 317 } 318 319 return true; 320} 321 322// Determines the context to return to after temporarily entering a 323// context. This depends in an unnecessarily complicated way on the 324// exact ordering of callbacks from the parser. 325DeclContext *Sema::getContainingDC(DeclContext *DC) { 326 327 // Functions defined inline within classes aren't parsed until we've 328 // finished parsing the top-level class, so the top-level class is 329 // the context we'll need to return to. 330 if (isa<FunctionDecl>(DC)) { 331 DC = DC->getLexicalParent(); 332 333 // A function not defined within a class will always return to its 334 // lexical context. 335 if (!isa<CXXRecordDecl>(DC)) 336 return DC; 337 338 // A C++ inline method/friend is parsed *after* the topmost class 339 // it was declared in is fully parsed ("complete"); the topmost 340 // class is the context we need to return to. 341 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 342 DC = RD; 343 344 // Return the declaration context of the topmost class the inline method is 345 // declared in. 346 return DC; 347 } 348 349 if (isa<ObjCMethodDecl>(DC)) 350 return Context.getTranslationUnitDecl(); 351 352 return DC->getLexicalParent(); 353} 354 355void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 356 assert(getContainingDC(DC) == CurContext && 357 "The next DeclContext should be lexically contained in the current one."); 358 CurContext = DC; 359 S->setEntity(DC); 360} 361 362void Sema::PopDeclContext() { 363 assert(CurContext && "DeclContext imbalance!"); 364 365 CurContext = getContainingDC(CurContext); 366} 367 368/// EnterDeclaratorContext - Used when we must lookup names in the context 369/// of a declarator's nested name specifier. 370/// 371void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 372 // C++0x [basic.lookup.unqual]p13: 373 // A name used in the definition of a static data member of class 374 // X (after the qualified-id of the static member) is looked up as 375 // if the name was used in a member function of X. 376 // C++0x [basic.lookup.unqual]p14: 377 // If a variable member of a namespace is defined outside of the 378 // scope of its namespace then any name used in the definition of 379 // the variable member (after the declarator-id) is looked up as 380 // if the definition of the variable member occurred in its 381 // namespace. 382 // Both of these imply that we should push a scope whose context 383 // is the semantic context of the declaration. We can't use 384 // PushDeclContext here because that context is not necessarily 385 // lexically contained in the current context. Fortunately, 386 // the containing scope should have the appropriate information. 387 388 assert(!S->getEntity() && "scope already has entity"); 389 390#ifndef NDEBUG 391 Scope *Ancestor = S->getParent(); 392 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 393 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 394#endif 395 396 CurContext = DC; 397 S->setEntity(DC); 398} 399 400void Sema::ExitDeclaratorContext(Scope *S) { 401 assert(S->getEntity() == CurContext && "Context imbalance!"); 402 403 // Switch back to the lexical context. The safety of this is 404 // enforced by an assert in EnterDeclaratorContext. 405 Scope *Ancestor = S->getParent(); 406 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 407 CurContext = (DeclContext*) Ancestor->getEntity(); 408 409 // We don't need to do anything with the scope, which is going to 410 // disappear. 411} 412 413/// \brief Determine whether we allow overloading of the function 414/// PrevDecl with another declaration. 415/// 416/// This routine determines whether overloading is possible, not 417/// whether some new function is actually an overload. It will return 418/// true in C++ (where we can always provide overloads) or, as an 419/// extension, in C when the previous function is already an 420/// overloaded function declaration or has the "overloadable" 421/// attribute. 422static bool AllowOverloadingOfFunction(LookupResult &Previous, 423 ASTContext &Context) { 424 if (Context.getLangOptions().CPlusPlus) 425 return true; 426 427 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 428 return true; 429 430 return (Previous.getResultKind() == LookupResult::Found 431 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 432} 433 434/// Add this decl to the scope shadowed decl chains. 435void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 436 // Move up the scope chain until we find the nearest enclosing 437 // non-transparent context. The declaration will be introduced into this 438 // scope. 439 while (S->getEntity() && 440 ((DeclContext *)S->getEntity())->isTransparentContext()) 441 S = S->getParent(); 442 443 // Add scoped declarations into their context, so that they can be 444 // found later. Declarations without a context won't be inserted 445 // into any context. 446 if (AddToContext) 447 CurContext->addDecl(D); 448 449 // Out-of-line definitions shouldn't be pushed into scope in C++. 450 // Out-of-line variable and function definitions shouldn't even in C. 451 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 452 D->isOutOfLine()) 453 return; 454 455 // Template instantiations should also not be pushed into scope. 456 if (isa<FunctionDecl>(D) && 457 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 458 return; 459 460 // If this replaces anything in the current scope, 461 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 462 IEnd = IdResolver.end(); 463 for (; I != IEnd; ++I) { 464 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 465 S->RemoveDecl(DeclPtrTy::make(*I)); 466 IdResolver.RemoveDecl(*I); 467 468 // Should only need to replace one decl. 469 break; 470 } 471 } 472 473 S->AddDecl(DeclPtrTy::make(D)); 474 IdResolver.AddDecl(D); 475} 476 477bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 478 return IdResolver.isDeclInScope(D, Ctx, Context, S); 479} 480 481static bool isOutOfScopePreviousDeclaration(NamedDecl *, 482 DeclContext*, 483 ASTContext&); 484 485/// Filters out lookup results that don't fall within the given scope 486/// as determined by isDeclInScope. 487static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 488 DeclContext *Ctx, Scope *S, 489 bool ConsiderLinkage) { 490 LookupResult::Filter F = R.makeFilter(); 491 while (F.hasNext()) { 492 NamedDecl *D = F.next(); 493 494 if (SemaRef.isDeclInScope(D, Ctx, S)) 495 continue; 496 497 if (ConsiderLinkage && 498 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 499 continue; 500 501 F.erase(); 502 } 503 504 F.done(); 505} 506 507static bool isUsingDecl(NamedDecl *D) { 508 return isa<UsingShadowDecl>(D) || 509 isa<UnresolvedUsingTypenameDecl>(D) || 510 isa<UnresolvedUsingValueDecl>(D); 511} 512 513/// Removes using shadow declarations from the lookup results. 514static void RemoveUsingDecls(LookupResult &R) { 515 LookupResult::Filter F = R.makeFilter(); 516 while (F.hasNext()) 517 if (isUsingDecl(F.next())) 518 F.erase(); 519 520 F.done(); 521} 522 523static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 524 if (D->isInvalidDecl()) 525 return false; 526 527 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 528 return false; 529 530 // White-list anything that isn't a local variable. 531 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 532 !D->getDeclContext()->isFunctionOrMethod()) 533 return false; 534 535 // Types of valid local variables should be complete, so this should succeed. 536 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 537 538 // White-list anything with an __attribute__((unused)) type. 539 QualType Ty = VD->getType(); 540 541 // Only look at the outermost level of typedef. 542 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 543 if (TT->getDecl()->hasAttr<UnusedAttr>()) 544 return false; 545 } 546 547 if (const TagType *TT = Ty->getAs<TagType>()) { 548 const TagDecl *Tag = TT->getDecl(); 549 if (Tag->hasAttr<UnusedAttr>()) 550 return false; 551 552 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 553 if (!RD->hasTrivialConstructor()) 554 return false; 555 if (!RD->hasTrivialDestructor()) 556 return false; 557 } 558 } 559 560 // TODO: __attribute__((unused)) templates? 561 } 562 563 return true; 564} 565 566void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 567 if (S->decl_empty()) return; 568 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 569 "Scope shouldn't contain decls!"); 570 571 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 572 I != E; ++I) { 573 Decl *TmpD = (*I).getAs<Decl>(); 574 assert(TmpD && "This decl didn't get pushed??"); 575 576 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 577 NamedDecl *D = cast<NamedDecl>(TmpD); 578 579 if (!D->getDeclName()) continue; 580 581 // Diagnose unused variables in this scope. 582 if (ShouldDiagnoseUnusedDecl(D) && 583 S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 584 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 585 586 // Remove this name from our lexical scope. 587 IdResolver.RemoveDecl(D); 588 } 589} 590 591/// \brief Look for an Objective-C class in the translation unit. 592/// 593/// \param Id The name of the Objective-C class we're looking for. If 594/// typo-correction fixes this name, the Id will be updated 595/// to the fixed name. 596/// 597/// \param IdLoc The location of the name in the translation unit. 598/// 599/// \param TypoCorrection If true, this routine will attempt typo correction 600/// if there is no class with the given name. 601/// 602/// \returns The declaration of the named Objective-C class, or NULL if the 603/// class could not be found. 604ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 605 SourceLocation IdLoc, 606 bool TypoCorrection) { 607 // The third "scope" argument is 0 since we aren't enabling lazy built-in 608 // creation from this context. 609 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 610 611 if (!IDecl && TypoCorrection) { 612 // Perform typo correction at the given location, but only if we 613 // find an Objective-C class name. 614 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 615 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 616 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 617 Diag(IdLoc, diag::err_undef_interface_suggest) 618 << Id << IDecl->getDeclName() 619 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 620 Diag(IDecl->getLocation(), diag::note_previous_decl) 621 << IDecl->getDeclName(); 622 623 Id = IDecl->getIdentifier(); 624 } 625 } 626 627 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 628} 629 630/// getNonFieldDeclScope - Retrieves the innermost scope, starting 631/// from S, where a non-field would be declared. This routine copes 632/// with the difference between C and C++ scoping rules in structs and 633/// unions. For example, the following code is well-formed in C but 634/// ill-formed in C++: 635/// @code 636/// struct S6 { 637/// enum { BAR } e; 638/// }; 639/// 640/// void test_S6() { 641/// struct S6 a; 642/// a.e = BAR; 643/// } 644/// @endcode 645/// For the declaration of BAR, this routine will return a different 646/// scope. The scope S will be the scope of the unnamed enumeration 647/// within S6. In C++, this routine will return the scope associated 648/// with S6, because the enumeration's scope is a transparent 649/// context but structures can contain non-field names. In C, this 650/// routine will return the translation unit scope, since the 651/// enumeration's scope is a transparent context and structures cannot 652/// contain non-field names. 653Scope *Sema::getNonFieldDeclScope(Scope *S) { 654 while (((S->getFlags() & Scope::DeclScope) == 0) || 655 (S->getEntity() && 656 ((DeclContext *)S->getEntity())->isTransparentContext()) || 657 (S->isClassScope() && !getLangOptions().CPlusPlus)) 658 S = S->getParent(); 659 return S; 660} 661 662void Sema::InitBuiltinVaListType() { 663 if (!Context.getBuiltinVaListType().isNull()) 664 return; 665 666 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 667 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 668 LookupOrdinaryName, ForRedeclaration); 669 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 670 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 671} 672 673/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 674/// file scope. lazily create a decl for it. ForRedeclaration is true 675/// if we're creating this built-in in anticipation of redeclaring the 676/// built-in. 677NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 678 Scope *S, bool ForRedeclaration, 679 SourceLocation Loc) { 680 Builtin::ID BID = (Builtin::ID)bid; 681 682 if (Context.BuiltinInfo.hasVAListUse(BID)) 683 InitBuiltinVaListType(); 684 685 ASTContext::GetBuiltinTypeError Error; 686 QualType R = Context.GetBuiltinType(BID, Error); 687 switch (Error) { 688 case ASTContext::GE_None: 689 // Okay 690 break; 691 692 case ASTContext::GE_Missing_stdio: 693 if (ForRedeclaration) 694 Diag(Loc, diag::err_implicit_decl_requires_stdio) 695 << Context.BuiltinInfo.GetName(BID); 696 return 0; 697 698 case ASTContext::GE_Missing_setjmp: 699 if (ForRedeclaration) 700 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 701 << Context.BuiltinInfo.GetName(BID); 702 return 0; 703 } 704 705 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 706 Diag(Loc, diag::ext_implicit_lib_function_decl) 707 << Context.BuiltinInfo.GetName(BID) 708 << R; 709 if (Context.BuiltinInfo.getHeaderName(BID) && 710 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 711 != Diagnostic::Ignored) 712 Diag(Loc, diag::note_please_include_header) 713 << Context.BuiltinInfo.getHeaderName(BID) 714 << Context.BuiltinInfo.GetName(BID); 715 } 716 717 FunctionDecl *New = FunctionDecl::Create(Context, 718 Context.getTranslationUnitDecl(), 719 Loc, II, R, /*TInfo=*/0, 720 FunctionDecl::Extern, false, 721 /*hasPrototype=*/true); 722 New->setImplicit(); 723 724 // Create Decl objects for each parameter, adding them to the 725 // FunctionDecl. 726 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 727 llvm::SmallVector<ParmVarDecl*, 16> Params; 728 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 729 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 730 FT->getArgType(i), /*TInfo=*/0, 731 VarDecl::None, 0)); 732 New->setParams(Params.data(), Params.size()); 733 } 734 735 AddKnownFunctionAttributes(New); 736 737 // TUScope is the translation-unit scope to insert this function into. 738 // FIXME: This is hideous. We need to teach PushOnScopeChains to 739 // relate Scopes to DeclContexts, and probably eliminate CurContext 740 // entirely, but we're not there yet. 741 DeclContext *SavedContext = CurContext; 742 CurContext = Context.getTranslationUnitDecl(); 743 PushOnScopeChains(New, TUScope); 744 CurContext = SavedContext; 745 return New; 746} 747 748/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 749/// same name and scope as a previous declaration 'Old'. Figure out 750/// how to resolve this situation, merging decls or emitting 751/// diagnostics as appropriate. If there was an error, set New to be invalid. 752/// 753void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 754 // If the new decl is known invalid already, don't bother doing any 755 // merging checks. 756 if (New->isInvalidDecl()) return; 757 758 // Allow multiple definitions for ObjC built-in typedefs. 759 // FIXME: Verify the underlying types are equivalent! 760 if (getLangOptions().ObjC1) { 761 const IdentifierInfo *TypeID = New->getIdentifier(); 762 switch (TypeID->getLength()) { 763 default: break; 764 case 2: 765 if (!TypeID->isStr("id")) 766 break; 767 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 768 // Install the built-in type for 'id', ignoring the current definition. 769 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 770 return; 771 case 5: 772 if (!TypeID->isStr("Class")) 773 break; 774 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 775 // Install the built-in type for 'Class', ignoring the current definition. 776 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 777 return; 778 case 3: 779 if (!TypeID->isStr("SEL")) 780 break; 781 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 782 // Install the built-in type for 'SEL', ignoring the current definition. 783 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 784 return; 785 case 8: 786 if (!TypeID->isStr("Protocol")) 787 break; 788 Context.setObjCProtoType(New->getUnderlyingType()); 789 return; 790 } 791 // Fall through - the typedef name was not a builtin type. 792 } 793 794 // Verify the old decl was also a type. 795 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 796 if (!Old) { 797 Diag(New->getLocation(), diag::err_redefinition_different_kind) 798 << New->getDeclName(); 799 800 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 801 if (OldD->getLocation().isValid()) 802 Diag(OldD->getLocation(), diag::note_previous_definition); 803 804 return New->setInvalidDecl(); 805 } 806 807 // If the old declaration is invalid, just give up here. 808 if (Old->isInvalidDecl()) 809 return New->setInvalidDecl(); 810 811 // Determine the "old" type we'll use for checking and diagnostics. 812 QualType OldType; 813 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 814 OldType = OldTypedef->getUnderlyingType(); 815 else 816 OldType = Context.getTypeDeclType(Old); 817 818 // If the typedef types are not identical, reject them in all languages and 819 // with any extensions enabled. 820 821 if (OldType != New->getUnderlyingType() && 822 Context.getCanonicalType(OldType) != 823 Context.getCanonicalType(New->getUnderlyingType())) { 824 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 825 << New->getUnderlyingType() << OldType; 826 if (Old->getLocation().isValid()) 827 Diag(Old->getLocation(), diag::note_previous_definition); 828 return New->setInvalidDecl(); 829 } 830 831 // The types match. Link up the redeclaration chain if the old 832 // declaration was a typedef. 833 // FIXME: this is a potential source of wierdness if the type 834 // spellings don't match exactly. 835 if (isa<TypedefDecl>(Old)) 836 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 837 838 if (getLangOptions().Microsoft) 839 return; 840 841 if (getLangOptions().CPlusPlus) { 842 // C++ [dcl.typedef]p2: 843 // In a given non-class scope, a typedef specifier can be used to 844 // redefine the name of any type declared in that scope to refer 845 // to the type to which it already refers. 846 if (!isa<CXXRecordDecl>(CurContext)) 847 return; 848 849 // C++0x [dcl.typedef]p4: 850 // In a given class scope, a typedef specifier can be used to redefine 851 // any class-name declared in that scope that is not also a typedef-name 852 // to refer to the type to which it already refers. 853 // 854 // This wording came in via DR424, which was a correction to the 855 // wording in DR56, which accidentally banned code like: 856 // 857 // struct S { 858 // typedef struct A { } A; 859 // }; 860 // 861 // in the C++03 standard. We implement the C++0x semantics, which 862 // allow the above but disallow 863 // 864 // struct S { 865 // typedef int I; 866 // typedef int I; 867 // }; 868 // 869 // since that was the intent of DR56. 870 if (!isa<TypedefDecl >(Old)) 871 return; 872 873 Diag(New->getLocation(), diag::err_redefinition) 874 << New->getDeclName(); 875 Diag(Old->getLocation(), diag::note_previous_definition); 876 return New->setInvalidDecl(); 877 } 878 879 // If we have a redefinition of a typedef in C, emit a warning. This warning 880 // is normally mapped to an error, but can be controlled with 881 // -Wtypedef-redefinition. If either the original or the redefinition is 882 // in a system header, don't emit this for compatibility with GCC. 883 if (getDiagnostics().getSuppressSystemWarnings() && 884 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 885 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 886 return; 887 888 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 889 << New->getDeclName(); 890 Diag(Old->getLocation(), diag::note_previous_definition); 891 return; 892} 893 894/// DeclhasAttr - returns true if decl Declaration already has the target 895/// attribute. 896static bool 897DeclHasAttr(const Decl *decl, const Attr *target) { 898 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 899 if (attr->getKind() == target->getKind()) 900 return true; 901 902 return false; 903} 904 905/// MergeAttributes - append attributes from the Old decl to the New one. 906static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 907 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 908 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 909 Attr *NewAttr = attr->clone(C); 910 NewAttr->setInherited(true); 911 New->addAttr(NewAttr); 912 } 913 } 914} 915 916/// Used in MergeFunctionDecl to keep track of function parameters in 917/// C. 918struct GNUCompatibleParamWarning { 919 ParmVarDecl *OldParm; 920 ParmVarDecl *NewParm; 921 QualType PromotedType; 922}; 923 924 925/// getSpecialMember - get the special member enum for a method. 926static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 927 const CXXMethodDecl *MD) { 928 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 929 if (Ctor->isDefaultConstructor()) 930 return Sema::CXXDefaultConstructor; 931 if (Ctor->isCopyConstructor()) 932 return Sema::CXXCopyConstructor; 933 } 934 935 if (isa<CXXDestructorDecl>(MD)) 936 return Sema::CXXDestructor; 937 938 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 939 return Sema::CXXCopyAssignment; 940} 941 942/// canREdefineFunction - checks if a function can be redefined. Currently, 943/// only extern inline functions can be redefined, and even then only in 944/// GNU89 mode. 945static bool canRedefineFunction(const FunctionDecl *FD, 946 const LangOptions& LangOpts) { 947 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 948 FD->isInlineSpecified() && 949 FD->getStorageClass() == FunctionDecl::Extern); 950} 951 952/// MergeFunctionDecl - We just parsed a function 'New' from 953/// declarator D which has the same name and scope as a previous 954/// declaration 'Old'. Figure out how to resolve this situation, 955/// merging decls or emitting diagnostics as appropriate. 956/// 957/// In C++, New and Old must be declarations that are not 958/// overloaded. Use IsOverload to determine whether New and Old are 959/// overloaded, and to select the Old declaration that New should be 960/// merged with. 961/// 962/// Returns true if there was an error, false otherwise. 963bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 964 // Verify the old decl was also a function. 965 FunctionDecl *Old = 0; 966 if (FunctionTemplateDecl *OldFunctionTemplate 967 = dyn_cast<FunctionTemplateDecl>(OldD)) 968 Old = OldFunctionTemplate->getTemplatedDecl(); 969 else 970 Old = dyn_cast<FunctionDecl>(OldD); 971 if (!Old) { 972 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 973 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 974 Diag(Shadow->getTargetDecl()->getLocation(), 975 diag::note_using_decl_target); 976 Diag(Shadow->getUsingDecl()->getLocation(), 977 diag::note_using_decl) << 0; 978 return true; 979 } 980 981 Diag(New->getLocation(), diag::err_redefinition_different_kind) 982 << New->getDeclName(); 983 Diag(OldD->getLocation(), diag::note_previous_definition); 984 return true; 985 } 986 987 // Determine whether the previous declaration was a definition, 988 // implicit declaration, or a declaration. 989 diag::kind PrevDiag; 990 if (Old->isThisDeclarationADefinition()) 991 PrevDiag = diag::note_previous_definition; 992 else if (Old->isImplicit()) 993 PrevDiag = diag::note_previous_implicit_declaration; 994 else 995 PrevDiag = diag::note_previous_declaration; 996 997 QualType OldQType = Context.getCanonicalType(Old->getType()); 998 QualType NewQType = Context.getCanonicalType(New->getType()); 999 1000 // Don't complain about this if we're in GNU89 mode and the old function 1001 // is an extern inline function. 1002 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1003 New->getStorageClass() == FunctionDecl::Static && 1004 Old->getStorageClass() != FunctionDecl::Static && 1005 !canRedefineFunction(Old, getLangOptions())) { 1006 Diag(New->getLocation(), diag::err_static_non_static) 1007 << New; 1008 Diag(Old->getLocation(), PrevDiag); 1009 return true; 1010 } 1011 1012 // If a function is first declared with a calling convention, but is 1013 // later declared or defined without one, the second decl assumes the 1014 // calling convention of the first. 1015 // 1016 // For the new decl, we have to look at the NON-canonical type to tell the 1017 // difference between a function that really doesn't have a calling 1018 // convention and one that is declared cdecl. That's because in 1019 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1020 // because it is the default calling convention. 1021 // 1022 // Note also that we DO NOT return at this point, because we still have 1023 // other tests to run. 1024 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1025 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1026 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1027 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1028 if (OldTypeInfo.getCC() != CC_Default && 1029 NewTypeInfo.getCC() == CC_Default) { 1030 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1031 New->setType(NewQType); 1032 NewQType = Context.getCanonicalType(NewQType); 1033 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1034 NewTypeInfo.getCC())) { 1035 // Calling conventions really aren't compatible, so complain. 1036 Diag(New->getLocation(), diag::err_cconv_change) 1037 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1038 << (OldTypeInfo.getCC() == CC_Default) 1039 << (OldTypeInfo.getCC() == CC_Default ? "" : 1040 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1041 Diag(Old->getLocation(), diag::note_previous_declaration); 1042 return true; 1043 } 1044 1045 // FIXME: diagnose the other way around? 1046 if (OldType->getNoReturnAttr() && 1047 !NewType->getNoReturnAttr()) { 1048 NewQType = Context.getNoReturnType(NewQType); 1049 New->setType(NewQType); 1050 assert(NewQType.isCanonical()); 1051 } 1052 1053 if (getLangOptions().CPlusPlus) { 1054 // (C++98 13.1p2): 1055 // Certain function declarations cannot be overloaded: 1056 // -- Function declarations that differ only in the return type 1057 // cannot be overloaded. 1058 QualType OldReturnType 1059 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1060 QualType NewReturnType 1061 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1062 if (OldReturnType != NewReturnType) { 1063 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1064 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1065 return true; 1066 } 1067 1068 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1069 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1070 if (OldMethod && NewMethod) { 1071 // Preserve triviality. 1072 NewMethod->setTrivial(OldMethod->isTrivial()); 1073 1074 bool isFriend = NewMethod->getFriendObjectKind(); 1075 1076 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1077 // -- Member function declarations with the same name and the 1078 // same parameter types cannot be overloaded if any of them 1079 // is a static member function declaration. 1080 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1081 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1082 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1083 return true; 1084 } 1085 1086 // C++ [class.mem]p1: 1087 // [...] A member shall not be declared twice in the 1088 // member-specification, except that a nested class or member 1089 // class template can be declared and then later defined. 1090 unsigned NewDiag; 1091 if (isa<CXXConstructorDecl>(OldMethod)) 1092 NewDiag = diag::err_constructor_redeclared; 1093 else if (isa<CXXDestructorDecl>(NewMethod)) 1094 NewDiag = diag::err_destructor_redeclared; 1095 else if (isa<CXXConversionDecl>(NewMethod)) 1096 NewDiag = diag::err_conv_function_redeclared; 1097 else 1098 NewDiag = diag::err_member_redeclared; 1099 1100 Diag(New->getLocation(), NewDiag); 1101 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1102 1103 // Complain if this is an explicit declaration of a special 1104 // member that was initially declared implicitly. 1105 // 1106 // As an exception, it's okay to befriend such methods in order 1107 // to permit the implicit constructor/destructor/operator calls. 1108 } else if (OldMethod->isImplicit()) { 1109 if (isFriend) { 1110 NewMethod->setImplicit(); 1111 } else { 1112 Diag(NewMethod->getLocation(), 1113 diag::err_definition_of_implicitly_declared_member) 1114 << New << getSpecialMember(Context, OldMethod); 1115 return true; 1116 } 1117 } 1118 } 1119 1120 // (C++98 8.3.5p3): 1121 // All declarations for a function shall agree exactly in both the 1122 // return type and the parameter-type-list. 1123 // attributes should be ignored when comparing. 1124 if (Context.getNoReturnType(OldQType, false) == 1125 Context.getNoReturnType(NewQType, false)) 1126 return MergeCompatibleFunctionDecls(New, Old); 1127 1128 // Fall through for conflicting redeclarations and redefinitions. 1129 } 1130 1131 // C: Function types need to be compatible, not identical. This handles 1132 // duplicate function decls like "void f(int); void f(enum X);" properly. 1133 if (!getLangOptions().CPlusPlus && 1134 Context.typesAreCompatible(OldQType, NewQType)) { 1135 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1136 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1137 const FunctionProtoType *OldProto = 0; 1138 if (isa<FunctionNoProtoType>(NewFuncType) && 1139 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1140 // The old declaration provided a function prototype, but the 1141 // new declaration does not. Merge in the prototype. 1142 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1143 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1144 OldProto->arg_type_end()); 1145 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1146 ParamTypes.data(), ParamTypes.size(), 1147 OldProto->isVariadic(), 1148 OldProto->getTypeQuals(), 1149 false, false, 0, 0, 1150 OldProto->getExtInfo()); 1151 New->setType(NewQType); 1152 New->setHasInheritedPrototype(); 1153 1154 // Synthesize a parameter for each argument type. 1155 llvm::SmallVector<ParmVarDecl*, 16> Params; 1156 for (FunctionProtoType::arg_type_iterator 1157 ParamType = OldProto->arg_type_begin(), 1158 ParamEnd = OldProto->arg_type_end(); 1159 ParamType != ParamEnd; ++ParamType) { 1160 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1161 SourceLocation(), 0, 1162 *ParamType, /*TInfo=*/0, 1163 VarDecl::None, 0); 1164 Param->setImplicit(); 1165 Params.push_back(Param); 1166 } 1167 1168 New->setParams(Params.data(), Params.size()); 1169 } 1170 1171 return MergeCompatibleFunctionDecls(New, Old); 1172 } 1173 1174 // GNU C permits a K&R definition to follow a prototype declaration 1175 // if the declared types of the parameters in the K&R definition 1176 // match the types in the prototype declaration, even when the 1177 // promoted types of the parameters from the K&R definition differ 1178 // from the types in the prototype. GCC then keeps the types from 1179 // the prototype. 1180 // 1181 // If a variadic prototype is followed by a non-variadic K&R definition, 1182 // the K&R definition becomes variadic. This is sort of an edge case, but 1183 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1184 // C99 6.9.1p8. 1185 if (!getLangOptions().CPlusPlus && 1186 Old->hasPrototype() && !New->hasPrototype() && 1187 New->getType()->getAs<FunctionProtoType>() && 1188 Old->getNumParams() == New->getNumParams()) { 1189 llvm::SmallVector<QualType, 16> ArgTypes; 1190 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1191 const FunctionProtoType *OldProto 1192 = Old->getType()->getAs<FunctionProtoType>(); 1193 const FunctionProtoType *NewProto 1194 = New->getType()->getAs<FunctionProtoType>(); 1195 1196 // Determine whether this is the GNU C extension. 1197 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1198 NewProto->getResultType()); 1199 bool LooseCompatible = !MergedReturn.isNull(); 1200 for (unsigned Idx = 0, End = Old->getNumParams(); 1201 LooseCompatible && Idx != End; ++Idx) { 1202 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1203 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1204 if (Context.typesAreCompatible(OldParm->getType(), 1205 NewProto->getArgType(Idx))) { 1206 ArgTypes.push_back(NewParm->getType()); 1207 } else if (Context.typesAreCompatible(OldParm->getType(), 1208 NewParm->getType())) { 1209 GNUCompatibleParamWarning Warn 1210 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1211 Warnings.push_back(Warn); 1212 ArgTypes.push_back(NewParm->getType()); 1213 } else 1214 LooseCompatible = false; 1215 } 1216 1217 if (LooseCompatible) { 1218 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1219 Diag(Warnings[Warn].NewParm->getLocation(), 1220 diag::ext_param_promoted_not_compatible_with_prototype) 1221 << Warnings[Warn].PromotedType 1222 << Warnings[Warn].OldParm->getType(); 1223 Diag(Warnings[Warn].OldParm->getLocation(), 1224 diag::note_previous_declaration); 1225 } 1226 1227 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1228 ArgTypes.size(), 1229 OldProto->isVariadic(), 0, 1230 false, false, 0, 0, 1231 OldProto->getExtInfo())); 1232 return MergeCompatibleFunctionDecls(New, Old); 1233 } 1234 1235 // Fall through to diagnose conflicting types. 1236 } 1237 1238 // A function that has already been declared has been redeclared or defined 1239 // with a different type- show appropriate diagnostic 1240 if (unsigned BuiltinID = Old->getBuiltinID()) { 1241 // The user has declared a builtin function with an incompatible 1242 // signature. 1243 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1244 // The function the user is redeclaring is a library-defined 1245 // function like 'malloc' or 'printf'. Warn about the 1246 // redeclaration, then pretend that we don't know about this 1247 // library built-in. 1248 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1249 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1250 << Old << Old->getType(); 1251 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1252 Old->setInvalidDecl(); 1253 return false; 1254 } 1255 1256 PrevDiag = diag::note_previous_builtin_declaration; 1257 } 1258 1259 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1260 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1261 return true; 1262} 1263 1264/// \brief Completes the merge of two function declarations that are 1265/// known to be compatible. 1266/// 1267/// This routine handles the merging of attributes and other 1268/// properties of function declarations form the old declaration to 1269/// the new declaration, once we know that New is in fact a 1270/// redeclaration of Old. 1271/// 1272/// \returns false 1273bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1274 // Merge the attributes 1275 MergeAttributes(New, Old, Context); 1276 1277 // Merge the storage class. 1278 if (Old->getStorageClass() != FunctionDecl::Extern && 1279 Old->getStorageClass() != FunctionDecl::None) 1280 New->setStorageClass(Old->getStorageClass()); 1281 1282 // Merge "pure" flag. 1283 if (Old->isPure()) 1284 New->setPure(); 1285 1286 // Merge the "deleted" flag. 1287 if (Old->isDeleted()) 1288 New->setDeleted(); 1289 1290 if (getLangOptions().CPlusPlus) 1291 return MergeCXXFunctionDecl(New, Old); 1292 1293 return false; 1294} 1295 1296/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1297/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1298/// situation, merging decls or emitting diagnostics as appropriate. 1299/// 1300/// Tentative definition rules (C99 6.9.2p2) are checked by 1301/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1302/// definitions here, since the initializer hasn't been attached. 1303/// 1304void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1305 // If the new decl is already invalid, don't do any other checking. 1306 if (New->isInvalidDecl()) 1307 return; 1308 1309 // Verify the old decl was also a variable. 1310 VarDecl *Old = 0; 1311 if (!Previous.isSingleResult() || 1312 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1313 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1314 << New->getDeclName(); 1315 Diag(Previous.getRepresentativeDecl()->getLocation(), 1316 diag::note_previous_definition); 1317 return New->setInvalidDecl(); 1318 } 1319 1320 MergeAttributes(New, Old, Context); 1321 1322 // Merge the types 1323 QualType MergedT; 1324 if (getLangOptions().CPlusPlus) { 1325 if (Context.hasSameType(New->getType(), Old->getType())) 1326 MergedT = New->getType(); 1327 // C++ [basic.link]p10: 1328 // [...] the types specified by all declarations referring to a given 1329 // object or function shall be identical, except that declarations for an 1330 // array object can specify array types that differ by the presence or 1331 // absence of a major array bound (8.3.4). 1332 else if (Old->getType()->isIncompleteArrayType() && 1333 New->getType()->isArrayType()) { 1334 CanQual<ArrayType> OldArray 1335 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1336 CanQual<ArrayType> NewArray 1337 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1338 if (OldArray->getElementType() == NewArray->getElementType()) 1339 MergedT = New->getType(); 1340 } else if (Old->getType()->isArrayType() && 1341 New->getType()->isIncompleteArrayType()) { 1342 CanQual<ArrayType> OldArray 1343 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1344 CanQual<ArrayType> NewArray 1345 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1346 if (OldArray->getElementType() == NewArray->getElementType()) 1347 MergedT = Old->getType(); 1348 } 1349 } else { 1350 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1351 } 1352 if (MergedT.isNull()) { 1353 Diag(New->getLocation(), diag::err_redefinition_different_type) 1354 << New->getDeclName(); 1355 Diag(Old->getLocation(), diag::note_previous_definition); 1356 return New->setInvalidDecl(); 1357 } 1358 New->setType(MergedT); 1359 1360 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1361 if (New->getStorageClass() == VarDecl::Static && 1362 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1363 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1364 Diag(Old->getLocation(), diag::note_previous_definition); 1365 return New->setInvalidDecl(); 1366 } 1367 // C99 6.2.2p4: 1368 // For an identifier declared with the storage-class specifier 1369 // extern in a scope in which a prior declaration of that 1370 // identifier is visible,23) if the prior declaration specifies 1371 // internal or external linkage, the linkage of the identifier at 1372 // the later declaration is the same as the linkage specified at 1373 // the prior declaration. If no prior declaration is visible, or 1374 // if the prior declaration specifies no linkage, then the 1375 // identifier has external linkage. 1376 if (New->hasExternalStorage() && Old->hasLinkage()) 1377 /* Okay */; 1378 else if (New->getStorageClass() != VarDecl::Static && 1379 Old->getStorageClass() == VarDecl::Static) { 1380 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1381 Diag(Old->getLocation(), diag::note_previous_definition); 1382 return New->setInvalidDecl(); 1383 } 1384 1385 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1386 1387 // FIXME: The test for external storage here seems wrong? We still 1388 // need to check for mismatches. 1389 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1390 // Don't complain about out-of-line definitions of static members. 1391 !(Old->getLexicalDeclContext()->isRecord() && 1392 !New->getLexicalDeclContext()->isRecord())) { 1393 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1394 Diag(Old->getLocation(), diag::note_previous_definition); 1395 return New->setInvalidDecl(); 1396 } 1397 1398 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1399 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1400 Diag(Old->getLocation(), diag::note_previous_definition); 1401 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1402 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1403 Diag(Old->getLocation(), diag::note_previous_definition); 1404 } 1405 1406 // C++ doesn't have tentative definitions, so go right ahead and check here. 1407 const VarDecl *Def; 1408 if (getLangOptions().CPlusPlus && 1409 New->isThisDeclarationADefinition() == VarDecl::Definition && 1410 (Def = Old->getDefinition())) { 1411 Diag(New->getLocation(), diag::err_redefinition) 1412 << New->getDeclName(); 1413 Diag(Def->getLocation(), diag::note_previous_definition); 1414 New->setInvalidDecl(); 1415 return; 1416 } 1417 1418 // Keep a chain of previous declarations. 1419 New->setPreviousDeclaration(Old); 1420 1421 // Inherit access appropriately. 1422 New->setAccess(Old->getAccess()); 1423} 1424 1425/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1426/// no declarator (e.g. "struct foo;") is parsed. 1427Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1428 // FIXME: Error on auto/register at file scope 1429 // FIXME: Error on inline/virtual/explicit 1430 // FIXME: Warn on useless __thread 1431 // FIXME: Warn on useless const/volatile 1432 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1433 // FIXME: Warn on useless attributes 1434 Decl *TagD = 0; 1435 TagDecl *Tag = 0; 1436 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1437 DS.getTypeSpecType() == DeclSpec::TST_struct || 1438 DS.getTypeSpecType() == DeclSpec::TST_union || 1439 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1440 TagD = static_cast<Decl *>(DS.getTypeRep()); 1441 1442 if (!TagD) // We probably had an error 1443 return DeclPtrTy(); 1444 1445 // Note that the above type specs guarantee that the 1446 // type rep is a Decl, whereas in many of the others 1447 // it's a Type. 1448 Tag = dyn_cast<TagDecl>(TagD); 1449 } 1450 1451 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1452 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1453 // or incomplete types shall not be restrict-qualified." 1454 if (TypeQuals & DeclSpec::TQ_restrict) 1455 Diag(DS.getRestrictSpecLoc(), 1456 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1457 << DS.getSourceRange(); 1458 } 1459 1460 if (DS.isFriendSpecified()) { 1461 // If we're dealing with a class template decl, assume that the 1462 // template routines are handling it. 1463 if (TagD && isa<ClassTemplateDecl>(TagD)) 1464 return DeclPtrTy(); 1465 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1466 } 1467 1468 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1469 // If there are attributes in the DeclSpec, apply them to the record. 1470 if (const AttributeList *AL = DS.getAttributes()) 1471 ProcessDeclAttributeList(S, Record, AL); 1472 1473 if (!Record->getDeclName() && Record->isDefinition() && 1474 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1475 if (getLangOptions().CPlusPlus || 1476 Record->getDeclContext()->isRecord()) 1477 return BuildAnonymousStructOrUnion(S, DS, Record); 1478 1479 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1480 << DS.getSourceRange(); 1481 } 1482 1483 // Microsoft allows unnamed struct/union fields. Don't complain 1484 // about them. 1485 // FIXME: Should we support Microsoft's extensions in this area? 1486 if (Record->getDeclName() && getLangOptions().Microsoft) 1487 return DeclPtrTy::make(Tag); 1488 } 1489 1490 if (!DS.isMissingDeclaratorOk() && 1491 DS.getTypeSpecType() != DeclSpec::TST_error) { 1492 // Warn about typedefs of enums without names, since this is an 1493 // extension in both Microsoft an GNU. 1494 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1495 Tag && isa<EnumDecl>(Tag)) { 1496 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1497 << DS.getSourceRange(); 1498 return DeclPtrTy::make(Tag); 1499 } 1500 1501 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1502 << DS.getSourceRange(); 1503 } 1504 1505 return DeclPtrTy::make(Tag); 1506} 1507 1508/// We are trying to inject an anonymous member into the given scope; 1509/// check if there's an existing declaration that can't be overloaded. 1510/// 1511/// \return true if this is a forbidden redeclaration 1512static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1513 Scope *S, 1514 DeclContext *Owner, 1515 DeclarationName Name, 1516 SourceLocation NameLoc, 1517 unsigned diagnostic) { 1518 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1519 Sema::ForRedeclaration); 1520 if (!SemaRef.LookupName(R, S)) return false; 1521 1522 if (R.getAsSingle<TagDecl>()) 1523 return false; 1524 1525 // Pick a representative declaration. 1526 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1527 if (PrevDecl && Owner->isRecord()) { 1528 RecordDecl *Record = cast<RecordDecl>(Owner); 1529 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1530 return false; 1531 } 1532 1533 SemaRef.Diag(NameLoc, diagnostic) << Name; 1534 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1535 1536 return true; 1537} 1538 1539/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1540/// anonymous struct or union AnonRecord into the owning context Owner 1541/// and scope S. This routine will be invoked just after we realize 1542/// that an unnamed union or struct is actually an anonymous union or 1543/// struct, e.g., 1544/// 1545/// @code 1546/// union { 1547/// int i; 1548/// float f; 1549/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1550/// // f into the surrounding scope.x 1551/// @endcode 1552/// 1553/// This routine is recursive, injecting the names of nested anonymous 1554/// structs/unions into the owning context and scope as well. 1555bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1556 RecordDecl *AnonRecord) { 1557 unsigned diagKind 1558 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1559 : diag::err_anonymous_struct_member_redecl; 1560 1561 bool Invalid = false; 1562 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1563 FEnd = AnonRecord->field_end(); 1564 F != FEnd; ++F) { 1565 if ((*F)->getDeclName()) { 1566 if (CheckAnonMemberRedeclaration(*this, S, Owner, (*F)->getDeclName(), 1567 (*F)->getLocation(), diagKind)) { 1568 // C++ [class.union]p2: 1569 // The names of the members of an anonymous union shall be 1570 // distinct from the names of any other entity in the 1571 // scope in which the anonymous union is declared. 1572 Invalid = true; 1573 } else { 1574 // C++ [class.union]p2: 1575 // For the purpose of name lookup, after the anonymous union 1576 // definition, the members of the anonymous union are 1577 // considered to have been defined in the scope in which the 1578 // anonymous union is declared. 1579 Owner->makeDeclVisibleInContext(*F); 1580 S->AddDecl(DeclPtrTy::make(*F)); 1581 IdResolver.AddDecl(*F); 1582 } 1583 } else if (const RecordType *InnerRecordType 1584 = (*F)->getType()->getAs<RecordType>()) { 1585 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1586 if (InnerRecord->isAnonymousStructOrUnion()) 1587 Invalid = Invalid || 1588 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1589 } 1590 } 1591 1592 return Invalid; 1593} 1594 1595/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1596/// anonymous structure or union. Anonymous unions are a C++ feature 1597/// (C++ [class.union]) and a GNU C extension; anonymous structures 1598/// are a GNU C and GNU C++ extension. 1599Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1600 RecordDecl *Record) { 1601 DeclContext *Owner = Record->getDeclContext(); 1602 1603 // Diagnose whether this anonymous struct/union is an extension. 1604 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1605 Diag(Record->getLocation(), diag::ext_anonymous_union); 1606 else if (!Record->isUnion()) 1607 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1608 1609 // C and C++ require different kinds of checks for anonymous 1610 // structs/unions. 1611 bool Invalid = false; 1612 if (getLangOptions().CPlusPlus) { 1613 const char* PrevSpec = 0; 1614 unsigned DiagID; 1615 // C++ [class.union]p3: 1616 // Anonymous unions declared in a named namespace or in the 1617 // global namespace shall be declared static. 1618 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1619 (isa<TranslationUnitDecl>(Owner) || 1620 (isa<NamespaceDecl>(Owner) && 1621 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1622 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1623 Invalid = true; 1624 1625 // Recover by adding 'static'. 1626 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1627 PrevSpec, DiagID); 1628 } 1629 // C++ [class.union]p3: 1630 // A storage class is not allowed in a declaration of an 1631 // anonymous union in a class scope. 1632 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1633 isa<RecordDecl>(Owner)) { 1634 Diag(DS.getStorageClassSpecLoc(), 1635 diag::err_anonymous_union_with_storage_spec); 1636 Invalid = true; 1637 1638 // Recover by removing the storage specifier. 1639 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1640 PrevSpec, DiagID); 1641 } 1642 1643 // C++ [class.union]p2: 1644 // The member-specification of an anonymous union shall only 1645 // define non-static data members. [Note: nested types and 1646 // functions cannot be declared within an anonymous union. ] 1647 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1648 MemEnd = Record->decls_end(); 1649 Mem != MemEnd; ++Mem) { 1650 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1651 // C++ [class.union]p3: 1652 // An anonymous union shall not have private or protected 1653 // members (clause 11). 1654 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1655 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1656 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1657 Invalid = true; 1658 } 1659 } else if ((*Mem)->isImplicit()) { 1660 // Any implicit members are fine. 1661 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1662 // This is a type that showed up in an 1663 // elaborated-type-specifier inside the anonymous struct or 1664 // union, but which actually declares a type outside of the 1665 // anonymous struct or union. It's okay. 1666 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1667 if (!MemRecord->isAnonymousStructOrUnion() && 1668 MemRecord->getDeclName()) { 1669 // This is a nested type declaration. 1670 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1671 << (int)Record->isUnion(); 1672 Invalid = true; 1673 } 1674 } else { 1675 // We have something that isn't a non-static data 1676 // member. Complain about it. 1677 unsigned DK = diag::err_anonymous_record_bad_member; 1678 if (isa<TypeDecl>(*Mem)) 1679 DK = diag::err_anonymous_record_with_type; 1680 else if (isa<FunctionDecl>(*Mem)) 1681 DK = diag::err_anonymous_record_with_function; 1682 else if (isa<VarDecl>(*Mem)) 1683 DK = diag::err_anonymous_record_with_static; 1684 Diag((*Mem)->getLocation(), DK) 1685 << (int)Record->isUnion(); 1686 Invalid = true; 1687 } 1688 } 1689 } 1690 1691 if (!Record->isUnion() && !Owner->isRecord()) { 1692 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1693 << (int)getLangOptions().CPlusPlus; 1694 Invalid = true; 1695 } 1696 1697 // Mock up a declarator. 1698 Declarator Dc(DS, Declarator::TypeNameContext); 1699 TypeSourceInfo *TInfo = 0; 1700 GetTypeForDeclarator(Dc, S, &TInfo); 1701 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1702 1703 // Create a declaration for this anonymous struct/union. 1704 NamedDecl *Anon = 0; 1705 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1706 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1707 /*IdentifierInfo=*/0, 1708 Context.getTypeDeclType(Record), 1709 TInfo, 1710 /*BitWidth=*/0, /*Mutable=*/false); 1711 Anon->setAccess(AS_public); 1712 if (getLangOptions().CPlusPlus) 1713 FieldCollector->Add(cast<FieldDecl>(Anon)); 1714 } else { 1715 VarDecl::StorageClass SC; 1716 switch (DS.getStorageClassSpec()) { 1717 default: assert(0 && "Unknown storage class!"); 1718 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1719 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1720 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1721 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1722 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1723 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1724 case DeclSpec::SCS_mutable: 1725 // mutable can only appear on non-static class members, so it's always 1726 // an error here 1727 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1728 Invalid = true; 1729 SC = VarDecl::None; 1730 break; 1731 } 1732 1733 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1734 /*IdentifierInfo=*/0, 1735 Context.getTypeDeclType(Record), 1736 TInfo, 1737 SC); 1738 } 1739 Anon->setImplicit(); 1740 1741 // Add the anonymous struct/union object to the current 1742 // context. We'll be referencing this object when we refer to one of 1743 // its members. 1744 Owner->addDecl(Anon); 1745 1746 // Inject the members of the anonymous struct/union into the owning 1747 // context and into the identifier resolver chain for name lookup 1748 // purposes. 1749 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1750 Invalid = true; 1751 1752 // Mark this as an anonymous struct/union type. Note that we do not 1753 // do this until after we have already checked and injected the 1754 // members of this anonymous struct/union type, because otherwise 1755 // the members could be injected twice: once by DeclContext when it 1756 // builds its lookup table, and once by 1757 // InjectAnonymousStructOrUnionMembers. 1758 Record->setAnonymousStructOrUnion(true); 1759 1760 if (Invalid) 1761 Anon->setInvalidDecl(); 1762 1763 return DeclPtrTy::make(Anon); 1764} 1765 1766 1767/// GetNameForDeclarator - Determine the full declaration name for the 1768/// given Declarator. 1769DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1770 return GetNameFromUnqualifiedId(D.getName()); 1771} 1772 1773/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1774DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1775 switch (Name.getKind()) { 1776 case UnqualifiedId::IK_Identifier: 1777 return DeclarationName(Name.Identifier); 1778 1779 case UnqualifiedId::IK_OperatorFunctionId: 1780 return Context.DeclarationNames.getCXXOperatorName( 1781 Name.OperatorFunctionId.Operator); 1782 1783 case UnqualifiedId::IK_LiteralOperatorId: 1784 return Context.DeclarationNames.getCXXLiteralOperatorName( 1785 Name.Identifier); 1786 1787 case UnqualifiedId::IK_ConversionFunctionId: { 1788 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1789 if (Ty.isNull()) 1790 return DeclarationName(); 1791 1792 return Context.DeclarationNames.getCXXConversionFunctionName( 1793 Context.getCanonicalType(Ty)); 1794 } 1795 1796 case UnqualifiedId::IK_ConstructorName: { 1797 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1798 if (Ty.isNull()) 1799 return DeclarationName(); 1800 1801 return Context.DeclarationNames.getCXXConstructorName( 1802 Context.getCanonicalType(Ty)); 1803 } 1804 1805 case UnqualifiedId::IK_ConstructorTemplateId: { 1806 // In well-formed code, we can only have a constructor 1807 // template-id that refers to the current context, so go there 1808 // to find the actual type being constructed. 1809 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1810 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1811 return DeclarationName(); 1812 1813 // Determine the type of the class being constructed. 1814 QualType CurClassType = Context.getTypeDeclType(CurClass); 1815 1816 // FIXME: Check two things: that the template-id names the same type as 1817 // CurClassType, and that the template-id does not occur when the name 1818 // was qualified. 1819 1820 return Context.DeclarationNames.getCXXConstructorName( 1821 Context.getCanonicalType(CurClassType)); 1822 } 1823 1824 case UnqualifiedId::IK_DestructorName: { 1825 QualType Ty = GetTypeFromParser(Name.DestructorName); 1826 if (Ty.isNull()) 1827 return DeclarationName(); 1828 1829 return Context.DeclarationNames.getCXXDestructorName( 1830 Context.getCanonicalType(Ty)); 1831 } 1832 1833 case UnqualifiedId::IK_TemplateId: { 1834 TemplateName TName 1835 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1836 return Context.getNameForTemplate(TName); 1837 } 1838 } 1839 1840 assert(false && "Unknown name kind"); 1841 return DeclarationName(); 1842} 1843 1844/// isNearlyMatchingFunction - Determine whether the C++ functions 1845/// Declaration and Definition are "nearly" matching. This heuristic 1846/// is used to improve diagnostics in the case where an out-of-line 1847/// function definition doesn't match any declaration within 1848/// the class or namespace. 1849static bool isNearlyMatchingFunction(ASTContext &Context, 1850 FunctionDecl *Declaration, 1851 FunctionDecl *Definition) { 1852 if (Declaration->param_size() != Definition->param_size()) 1853 return false; 1854 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1855 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1856 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1857 1858 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1859 DefParamTy.getNonReferenceType())) 1860 return false; 1861 } 1862 1863 return true; 1864} 1865 1866Sema::DeclPtrTy 1867Sema::HandleDeclarator(Scope *S, Declarator &D, 1868 MultiTemplateParamsArg TemplateParamLists, 1869 bool IsFunctionDefinition) { 1870 DeclarationName Name = GetNameForDeclarator(D); 1871 1872 // All of these full declarators require an identifier. If it doesn't have 1873 // one, the ParsedFreeStandingDeclSpec action should be used. 1874 if (!Name) { 1875 if (!D.isInvalidType()) // Reject this if we think it is valid. 1876 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1877 diag::err_declarator_need_ident) 1878 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1879 return DeclPtrTy(); 1880 } 1881 1882 // The scope passed in may not be a decl scope. Zip up the scope tree until 1883 // we find one that is. 1884 while ((S->getFlags() & Scope::DeclScope) == 0 || 1885 (S->getFlags() & Scope::TemplateParamScope) != 0) 1886 S = S->getParent(); 1887 1888 // If this is an out-of-line definition of a member of a class template 1889 // or class template partial specialization, we may need to rebuild the 1890 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1891 // for more information. 1892 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1893 // handle expressions properly. 1894 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1895 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1896 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1897 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1898 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1899 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1900 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1901 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1902 // FIXME: Preserve type source info. 1903 QualType T = GetTypeFromParser(DS.getTypeRep()); 1904 1905 DeclContext *SavedContext = CurContext; 1906 CurContext = DC; 1907 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1908 CurContext = SavedContext; 1909 1910 if (T.isNull()) 1911 return DeclPtrTy(); 1912 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1913 } 1914 } 1915 1916 DeclContext *DC; 1917 NamedDecl *New; 1918 1919 TypeSourceInfo *TInfo = 0; 1920 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1921 1922 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1923 ForRedeclaration); 1924 1925 // See if this is a redefinition of a variable in the same scope. 1926 if (D.getCXXScopeSpec().isInvalid()) { 1927 DC = CurContext; 1928 D.setInvalidType(); 1929 } else if (!D.getCXXScopeSpec().isSet()) { 1930 bool IsLinkageLookup = false; 1931 1932 // If the declaration we're planning to build will be a function 1933 // or object with linkage, then look for another declaration with 1934 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1935 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1936 /* Do nothing*/; 1937 else if (R->isFunctionType()) { 1938 if (CurContext->isFunctionOrMethod() || 1939 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1940 IsLinkageLookup = true; 1941 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1942 IsLinkageLookup = true; 1943 else if (CurContext->getLookupContext()->isTranslationUnit() && 1944 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1945 IsLinkageLookup = true; 1946 1947 if (IsLinkageLookup) 1948 Previous.clear(LookupRedeclarationWithLinkage); 1949 1950 DC = CurContext; 1951 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1952 } else { // Something like "int foo::x;" 1953 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1954 1955 if (!DC) { 1956 // If we could not compute the declaration context, it's because the 1957 // declaration context is dependent but does not refer to a class, 1958 // class template, or class template partial specialization. Complain 1959 // and return early, to avoid the coming semantic disaster. 1960 Diag(D.getIdentifierLoc(), 1961 diag::err_template_qualified_declarator_no_match) 1962 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1963 << D.getCXXScopeSpec().getRange(); 1964 return DeclPtrTy(); 1965 } 1966 1967 if (!DC->isDependentContext() && 1968 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1969 return DeclPtrTy(); 1970 1971 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 1972 Diag(D.getIdentifierLoc(), 1973 diag::err_member_def_undefined_record) 1974 << Name << DC << D.getCXXScopeSpec().getRange(); 1975 D.setInvalidType(); 1976 } 1977 1978 LookupQualifiedName(Previous, DC); 1979 1980 // Don't consider using declarations as previous declarations for 1981 // out-of-line members. 1982 RemoveUsingDecls(Previous); 1983 1984 // C++ 7.3.1.2p2: 1985 // Members (including explicit specializations of templates) of a named 1986 // namespace can also be defined outside that namespace by explicit 1987 // qualification of the name being defined, provided that the entity being 1988 // defined was already declared in the namespace and the definition appears 1989 // after the point of declaration in a namespace that encloses the 1990 // declarations namespace. 1991 // 1992 // Note that we only check the context at this point. We don't yet 1993 // have enough information to make sure that PrevDecl is actually 1994 // the declaration we want to match. For example, given: 1995 // 1996 // class X { 1997 // void f(); 1998 // void f(float); 1999 // }; 2000 // 2001 // void X::f(int) { } // ill-formed 2002 // 2003 // In this case, PrevDecl will point to the overload set 2004 // containing the two f's declared in X, but neither of them 2005 // matches. 2006 2007 // First check whether we named the global scope. 2008 if (isa<TranslationUnitDecl>(DC)) { 2009 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2010 << Name << D.getCXXScopeSpec().getRange(); 2011 } else { 2012 DeclContext *Cur = CurContext; 2013 while (isa<LinkageSpecDecl>(Cur)) 2014 Cur = Cur->getParent(); 2015 if (!Cur->Encloses(DC)) { 2016 // The qualifying scope doesn't enclose the original declaration. 2017 // Emit diagnostic based on current scope. 2018 SourceLocation L = D.getIdentifierLoc(); 2019 SourceRange R = D.getCXXScopeSpec().getRange(); 2020 if (isa<FunctionDecl>(Cur)) 2021 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2022 else 2023 Diag(L, diag::err_invalid_declarator_scope) 2024 << Name << cast<NamedDecl>(DC) << R; 2025 D.setInvalidType(); 2026 } 2027 } 2028 } 2029 2030 if (Previous.isSingleResult() && 2031 Previous.getFoundDecl()->isTemplateParameter()) { 2032 // Maybe we will complain about the shadowed template parameter. 2033 if (!D.isInvalidType()) 2034 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2035 Previous.getFoundDecl())) 2036 D.setInvalidType(); 2037 2038 // Just pretend that we didn't see the previous declaration. 2039 Previous.clear(); 2040 } 2041 2042 // In C++, the previous declaration we find might be a tag type 2043 // (class or enum). In this case, the new declaration will hide the 2044 // tag type. Note that this does does not apply if we're declaring a 2045 // typedef (C++ [dcl.typedef]p4). 2046 if (Previous.isSingleTagDecl() && 2047 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2048 Previous.clear(); 2049 2050 bool Redeclaration = false; 2051 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2052 if (TemplateParamLists.size()) { 2053 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2054 return DeclPtrTy(); 2055 } 2056 2057 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2058 } else if (R->isFunctionType()) { 2059 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2060 move(TemplateParamLists), 2061 IsFunctionDefinition, Redeclaration); 2062 } else { 2063 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2064 move(TemplateParamLists), 2065 Redeclaration); 2066 } 2067 2068 if (New == 0) 2069 return DeclPtrTy(); 2070 2071 // If this has an identifier and is not an invalid redeclaration or 2072 // function template specialization, add it to the scope stack. 2073 if (Name && !(Redeclaration && New->isInvalidDecl())) 2074 PushOnScopeChains(New, S); 2075 2076 return DeclPtrTy::make(New); 2077} 2078 2079/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2080/// types into constant array types in certain situations which would otherwise 2081/// be errors (for GCC compatibility). 2082static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2083 ASTContext &Context, 2084 bool &SizeIsNegative) { 2085 // This method tries to turn a variable array into a constant 2086 // array even when the size isn't an ICE. This is necessary 2087 // for compatibility with code that depends on gcc's buggy 2088 // constant expression folding, like struct {char x[(int)(char*)2];} 2089 SizeIsNegative = false; 2090 2091 QualifierCollector Qs; 2092 const Type *Ty = Qs.strip(T); 2093 2094 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2095 QualType Pointee = PTy->getPointeeType(); 2096 QualType FixedType = 2097 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2098 if (FixedType.isNull()) return FixedType; 2099 FixedType = Context.getPointerType(FixedType); 2100 return Qs.apply(FixedType); 2101 } 2102 2103 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2104 if (!VLATy) 2105 return QualType(); 2106 // FIXME: We should probably handle this case 2107 if (VLATy->getElementType()->isVariablyModifiedType()) 2108 return QualType(); 2109 2110 Expr::EvalResult EvalResult; 2111 if (!VLATy->getSizeExpr() || 2112 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2113 !EvalResult.Val.isInt()) 2114 return QualType(); 2115 2116 llvm::APSInt &Res = EvalResult.Val.getInt(); 2117 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2118 // TODO: preserve the size expression in declarator info 2119 return Context.getConstantArrayType(VLATy->getElementType(), 2120 Res, ArrayType::Normal, 0); 2121 } 2122 2123 SizeIsNegative = true; 2124 return QualType(); 2125} 2126 2127/// \brief Register the given locally-scoped external C declaration so 2128/// that it can be found later for redeclarations 2129void 2130Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2131 const LookupResult &Previous, 2132 Scope *S) { 2133 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2134 "Decl is not a locally-scoped decl!"); 2135 // Note that we have a locally-scoped external with this name. 2136 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2137 2138 if (!Previous.isSingleResult()) 2139 return; 2140 2141 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2142 2143 // If there was a previous declaration of this variable, it may be 2144 // in our identifier chain. Update the identifier chain with the new 2145 // declaration. 2146 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2147 // The previous declaration was found on the identifer resolver 2148 // chain, so remove it from its scope. 2149 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2150 S = S->getParent(); 2151 2152 if (S) 2153 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2154 } 2155} 2156 2157/// \brief Diagnose function specifiers on a declaration of an identifier that 2158/// does not identify a function. 2159void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2160 // FIXME: We should probably indicate the identifier in question to avoid 2161 // confusion for constructs like "inline int a(), b;" 2162 if (D.getDeclSpec().isInlineSpecified()) 2163 Diag(D.getDeclSpec().getInlineSpecLoc(), 2164 diag::err_inline_non_function); 2165 2166 if (D.getDeclSpec().isVirtualSpecified()) 2167 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2168 diag::err_virtual_non_function); 2169 2170 if (D.getDeclSpec().isExplicitSpecified()) 2171 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2172 diag::err_explicit_non_function); 2173} 2174 2175NamedDecl* 2176Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2177 QualType R, TypeSourceInfo *TInfo, 2178 LookupResult &Previous, bool &Redeclaration) { 2179 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2180 if (D.getCXXScopeSpec().isSet()) { 2181 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2182 << D.getCXXScopeSpec().getRange(); 2183 D.setInvalidType(); 2184 // Pretend we didn't see the scope specifier. 2185 DC = CurContext; 2186 Previous.clear(); 2187 } 2188 2189 if (getLangOptions().CPlusPlus) { 2190 // Check that there are no default arguments (C++ only). 2191 CheckExtraCXXDefaultArguments(D); 2192 } 2193 2194 DiagnoseFunctionSpecifiers(D); 2195 2196 if (D.getDeclSpec().isThreadSpecified()) 2197 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2198 2199 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2200 if (!NewTD) return 0; 2201 2202 // Handle attributes prior to checking for duplicates in MergeVarDecl 2203 ProcessDeclAttributes(S, NewTD, D); 2204 2205 // Merge the decl with the existing one if appropriate. If the decl is 2206 // in an outer scope, it isn't the same thing. 2207 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2208 if (!Previous.empty()) { 2209 Redeclaration = true; 2210 MergeTypeDefDecl(NewTD, Previous); 2211 } 2212 2213 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2214 // then it shall have block scope. 2215 QualType T = NewTD->getUnderlyingType(); 2216 if (T->isVariablyModifiedType()) { 2217 FunctionNeedsScopeChecking() = true; 2218 2219 if (S->getFnParent() == 0) { 2220 bool SizeIsNegative; 2221 QualType FixedTy = 2222 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2223 if (!FixedTy.isNull()) { 2224 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2225 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2226 } else { 2227 if (SizeIsNegative) 2228 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2229 else if (T->isVariableArrayType()) 2230 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2231 else 2232 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2233 NewTD->setInvalidDecl(); 2234 } 2235 } 2236 } 2237 2238 // If this is the C FILE type, notify the AST context. 2239 if (IdentifierInfo *II = NewTD->getIdentifier()) 2240 if (!NewTD->isInvalidDecl() && 2241 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2242 if (II->isStr("FILE")) 2243 Context.setFILEDecl(NewTD); 2244 else if (II->isStr("jmp_buf")) 2245 Context.setjmp_bufDecl(NewTD); 2246 else if (II->isStr("sigjmp_buf")) 2247 Context.setsigjmp_bufDecl(NewTD); 2248 } 2249 2250 return NewTD; 2251} 2252 2253/// \brief Determines whether the given declaration is an out-of-scope 2254/// previous declaration. 2255/// 2256/// This routine should be invoked when name lookup has found a 2257/// previous declaration (PrevDecl) that is not in the scope where a 2258/// new declaration by the same name is being introduced. If the new 2259/// declaration occurs in a local scope, previous declarations with 2260/// linkage may still be considered previous declarations (C99 2261/// 6.2.2p4-5, C++ [basic.link]p6). 2262/// 2263/// \param PrevDecl the previous declaration found by name 2264/// lookup 2265/// 2266/// \param DC the context in which the new declaration is being 2267/// declared. 2268/// 2269/// \returns true if PrevDecl is an out-of-scope previous declaration 2270/// for a new delcaration with the same name. 2271static bool 2272isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2273 ASTContext &Context) { 2274 if (!PrevDecl) 2275 return 0; 2276 2277 if (!PrevDecl->hasLinkage()) 2278 return false; 2279 2280 if (Context.getLangOptions().CPlusPlus) { 2281 // C++ [basic.link]p6: 2282 // If there is a visible declaration of an entity with linkage 2283 // having the same name and type, ignoring entities declared 2284 // outside the innermost enclosing namespace scope, the block 2285 // scope declaration declares that same entity and receives the 2286 // linkage of the previous declaration. 2287 DeclContext *OuterContext = DC->getLookupContext(); 2288 if (!OuterContext->isFunctionOrMethod()) 2289 // This rule only applies to block-scope declarations. 2290 return false; 2291 else { 2292 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2293 if (PrevOuterContext->isRecord()) 2294 // We found a member function: ignore it. 2295 return false; 2296 else { 2297 // Find the innermost enclosing namespace for the new and 2298 // previous declarations. 2299 while (!OuterContext->isFileContext()) 2300 OuterContext = OuterContext->getParent(); 2301 while (!PrevOuterContext->isFileContext()) 2302 PrevOuterContext = PrevOuterContext->getParent(); 2303 2304 // The previous declaration is in a different namespace, so it 2305 // isn't the same function. 2306 if (OuterContext->getPrimaryContext() != 2307 PrevOuterContext->getPrimaryContext()) 2308 return false; 2309 } 2310 } 2311 } 2312 2313 return true; 2314} 2315 2316static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2317 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2318 if (!SS.isSet()) return; 2319 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2320 SS.getRange()); 2321} 2322 2323NamedDecl* 2324Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2325 QualType R, TypeSourceInfo *TInfo, 2326 LookupResult &Previous, 2327 MultiTemplateParamsArg TemplateParamLists, 2328 bool &Redeclaration) { 2329 DeclarationName Name = GetNameForDeclarator(D); 2330 2331 // Check that there are no default arguments (C++ only). 2332 if (getLangOptions().CPlusPlus) 2333 CheckExtraCXXDefaultArguments(D); 2334 2335 VarDecl *NewVD; 2336 VarDecl::StorageClass SC; 2337 switch (D.getDeclSpec().getStorageClassSpec()) { 2338 default: assert(0 && "Unknown storage class!"); 2339 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2340 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2341 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2342 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2343 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2344 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2345 case DeclSpec::SCS_mutable: 2346 // mutable can only appear on non-static class members, so it's always 2347 // an error here 2348 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2349 D.setInvalidType(); 2350 SC = VarDecl::None; 2351 break; 2352 } 2353 2354 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2355 if (!II) { 2356 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2357 << Name.getAsString(); 2358 return 0; 2359 } 2360 2361 DiagnoseFunctionSpecifiers(D); 2362 2363 if (!DC->isRecord() && S->getFnParent() == 0) { 2364 // C99 6.9p2: The storage-class specifiers auto and register shall not 2365 // appear in the declaration specifiers in an external declaration. 2366 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2367 2368 // If this is a register variable with an asm label specified, then this 2369 // is a GNU extension. 2370 if (SC == VarDecl::Register && D.getAsmLabel()) 2371 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2372 else 2373 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2374 D.setInvalidType(); 2375 } 2376 } 2377 if (DC->isRecord() && !CurContext->isRecord()) { 2378 // This is an out-of-line definition of a static data member. 2379 if (SC == VarDecl::Static) { 2380 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2381 diag::err_static_out_of_line) 2382 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2383 } else if (SC == VarDecl::None) 2384 SC = VarDecl::Static; 2385 } 2386 if (SC == VarDecl::Static) { 2387 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2388 if (RD->isLocalClass()) 2389 Diag(D.getIdentifierLoc(), 2390 diag::err_static_data_member_not_allowed_in_local_class) 2391 << Name << RD->getDeclName(); 2392 } 2393 } 2394 2395 // Match up the template parameter lists with the scope specifier, then 2396 // determine whether we have a template or a template specialization. 2397 bool isExplicitSpecialization = false; 2398 if (TemplateParameterList *TemplateParams 2399 = MatchTemplateParametersToScopeSpecifier( 2400 D.getDeclSpec().getSourceRange().getBegin(), 2401 D.getCXXScopeSpec(), 2402 (TemplateParameterList**)TemplateParamLists.get(), 2403 TemplateParamLists.size(), 2404 /*never a friend*/ false, 2405 isExplicitSpecialization)) { 2406 if (TemplateParams->size() > 0) { 2407 // There is no such thing as a variable template. 2408 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2409 << II 2410 << SourceRange(TemplateParams->getTemplateLoc(), 2411 TemplateParams->getRAngleLoc()); 2412 return 0; 2413 } else { 2414 // There is an extraneous 'template<>' for this variable. Complain 2415 // about it, but allow the declaration of the variable. 2416 Diag(TemplateParams->getTemplateLoc(), 2417 diag::err_template_variable_noparams) 2418 << II 2419 << SourceRange(TemplateParams->getTemplateLoc(), 2420 TemplateParams->getRAngleLoc()); 2421 2422 isExplicitSpecialization = true; 2423 } 2424 } 2425 2426 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2427 II, R, TInfo, SC); 2428 2429 if (D.isInvalidType()) 2430 NewVD->setInvalidDecl(); 2431 2432 SetNestedNameSpecifier(NewVD, D); 2433 2434 if (D.getDeclSpec().isThreadSpecified()) { 2435 if (NewVD->hasLocalStorage()) 2436 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2437 else if (!Context.Target.isTLSSupported()) 2438 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2439 else 2440 NewVD->setThreadSpecified(true); 2441 } 2442 2443 // Set the lexical context. If the declarator has a C++ scope specifier, the 2444 // lexical context will be different from the semantic context. 2445 NewVD->setLexicalDeclContext(CurContext); 2446 2447 // Handle attributes prior to checking for duplicates in MergeVarDecl 2448 ProcessDeclAttributes(S, NewVD, D); 2449 2450 // Handle GNU asm-label extension (encoded as an attribute). 2451 if (Expr *E = (Expr*) D.getAsmLabel()) { 2452 // The parser guarantees this is a string. 2453 StringLiteral *SE = cast<StringLiteral>(E); 2454 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2455 } 2456 2457 // Diagnose shadowed variables before filtering for scope. 2458 if (!D.getCXXScopeSpec().isSet()) 2459 CheckShadow(S, NewVD, Previous); 2460 2461 // Don't consider existing declarations that are in a different 2462 // scope and are out-of-semantic-context declarations (if the new 2463 // declaration has linkage). 2464 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2465 2466 // Merge the decl with the existing one if appropriate. 2467 if (!Previous.empty()) { 2468 if (Previous.isSingleResult() && 2469 isa<FieldDecl>(Previous.getFoundDecl()) && 2470 D.getCXXScopeSpec().isSet()) { 2471 // The user tried to define a non-static data member 2472 // out-of-line (C++ [dcl.meaning]p1). 2473 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2474 << D.getCXXScopeSpec().getRange(); 2475 Previous.clear(); 2476 NewVD->setInvalidDecl(); 2477 } 2478 } else if (D.getCXXScopeSpec().isSet()) { 2479 // No previous declaration in the qualifying scope. 2480 Diag(D.getIdentifierLoc(), diag::err_no_member) 2481 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2482 << D.getCXXScopeSpec().getRange(); 2483 NewVD->setInvalidDecl(); 2484 } 2485 2486 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2487 2488 // This is an explicit specialization of a static data member. Check it. 2489 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2490 CheckMemberSpecialization(NewVD, Previous)) 2491 NewVD->setInvalidDecl(); 2492 2493 // attributes declared post-definition are currently ignored 2494 if (Previous.isSingleResult()) { 2495 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2496 if (Def && (Def = Def->getDefinition()) && 2497 Def != NewVD && D.hasAttributes()) { 2498 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2499 Diag(Def->getLocation(), diag::note_previous_definition); 2500 } 2501 } 2502 2503 // If this is a locally-scoped extern C variable, update the map of 2504 // such variables. 2505 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2506 !NewVD->isInvalidDecl()) 2507 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2508 2509 return NewVD; 2510} 2511 2512/// \brief Diagnose variable or built-in function shadowing. Implements 2513/// -Wshadow. 2514/// 2515/// This method is called whenever a VarDecl is added to a "useful" 2516/// scope. 2517/// 2518/// \param S the scope in which the shadowing name is being declared 2519/// \param R the lookup of the name 2520/// 2521void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2522 // Return if warning is ignored. 2523 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2524 return; 2525 2526 // Don't diagnose declarations at file scope. The scope might not 2527 // have a DeclContext if (e.g.) we're parsing a function prototype. 2528 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2529 if (NewDC && NewDC->isFileContext()) 2530 return; 2531 2532 // Only diagnose if we're shadowing an unambiguous field or variable. 2533 if (R.getResultKind() != LookupResult::Found) 2534 return; 2535 2536 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2537 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2538 return; 2539 2540 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2541 2542 // Only warn about certain kinds of shadowing for class members. 2543 if (NewDC && NewDC->isRecord()) { 2544 // In particular, don't warn about shadowing non-class members. 2545 if (!OldDC->isRecord()) 2546 return; 2547 2548 // TODO: should we warn about static data members shadowing 2549 // static data members from base classes? 2550 2551 // TODO: don't diagnose for inaccessible shadowed members. 2552 // This is hard to do perfectly because we might friend the 2553 // shadowing context, but that's just a false negative. 2554 } 2555 2556 // Determine what kind of declaration we're shadowing. 2557 unsigned Kind; 2558 if (isa<RecordDecl>(OldDC)) { 2559 if (isa<FieldDecl>(ShadowedDecl)) 2560 Kind = 3; // field 2561 else 2562 Kind = 2; // static data member 2563 } else if (OldDC->isFileContext()) 2564 Kind = 1; // global 2565 else 2566 Kind = 0; // local 2567 2568 DeclarationName Name = R.getLookupName(); 2569 2570 // Emit warning and note. 2571 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2572 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2573} 2574 2575/// \brief Check -Wshadow without the advantage of a previous lookup. 2576void Sema::CheckShadow(Scope *S, VarDecl *D) { 2577 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2578 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2579 LookupName(R, S); 2580 CheckShadow(S, D, R); 2581} 2582 2583/// \brief Perform semantic checking on a newly-created variable 2584/// declaration. 2585/// 2586/// This routine performs all of the type-checking required for a 2587/// variable declaration once it has been built. It is used both to 2588/// check variables after they have been parsed and their declarators 2589/// have been translated into a declaration, and to check variables 2590/// that have been instantiated from a template. 2591/// 2592/// Sets NewVD->isInvalidDecl() if an error was encountered. 2593void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2594 LookupResult &Previous, 2595 bool &Redeclaration) { 2596 // If the decl is already known invalid, don't check it. 2597 if (NewVD->isInvalidDecl()) 2598 return; 2599 2600 QualType T = NewVD->getType(); 2601 2602 if (T->isObjCInterfaceType()) { 2603 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2604 return NewVD->setInvalidDecl(); 2605 } 2606 2607 // Emit an error if an address space was applied to decl with local storage. 2608 // This includes arrays of objects with address space qualifiers, but not 2609 // automatic variables that point to other address spaces. 2610 // ISO/IEC TR 18037 S5.1.2 2611 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2612 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2613 return NewVD->setInvalidDecl(); 2614 } 2615 2616 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2617 && !NewVD->hasAttr<BlocksAttr>()) 2618 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2619 2620 bool isVM = T->isVariablyModifiedType(); 2621 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2622 NewVD->hasAttr<BlocksAttr>() || 2623 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2624 // However, this turns on the scope checker for everything with a variable 2625 // which may impact compile time. See if we can find a better solution 2626 // to this, perhaps only checking functions that contain gotos in C++? 2627 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2628 FunctionNeedsScopeChecking() = true; 2629 2630 if ((isVM && NewVD->hasLinkage()) || 2631 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2632 bool SizeIsNegative; 2633 QualType FixedTy = 2634 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2635 2636 if (FixedTy.isNull() && T->isVariableArrayType()) { 2637 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2638 // FIXME: This won't give the correct result for 2639 // int a[10][n]; 2640 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2641 2642 if (NewVD->isFileVarDecl()) 2643 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2644 << SizeRange; 2645 else if (NewVD->getStorageClass() == VarDecl::Static) 2646 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2647 << SizeRange; 2648 else 2649 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2650 << SizeRange; 2651 return NewVD->setInvalidDecl(); 2652 } 2653 2654 if (FixedTy.isNull()) { 2655 if (NewVD->isFileVarDecl()) 2656 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2657 else 2658 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2659 return NewVD->setInvalidDecl(); 2660 } 2661 2662 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2663 NewVD->setType(FixedTy); 2664 } 2665 2666 if (Previous.empty() && NewVD->isExternC()) { 2667 // Since we did not find anything by this name and we're declaring 2668 // an extern "C" variable, look for a non-visible extern "C" 2669 // declaration with the same name. 2670 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2671 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2672 if (Pos != LocallyScopedExternalDecls.end()) 2673 Previous.addDecl(Pos->second); 2674 } 2675 2676 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2677 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2678 << T; 2679 return NewVD->setInvalidDecl(); 2680 } 2681 2682 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2683 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2684 return NewVD->setInvalidDecl(); 2685 } 2686 2687 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2688 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2689 return NewVD->setInvalidDecl(); 2690 } 2691 2692 if (!Previous.empty()) { 2693 Redeclaration = true; 2694 MergeVarDecl(NewVD, Previous); 2695 } 2696} 2697 2698/// \brief Data used with FindOverriddenMethod 2699struct FindOverriddenMethodData { 2700 Sema *S; 2701 CXXMethodDecl *Method; 2702}; 2703 2704/// \brief Member lookup function that determines whether a given C++ 2705/// method overrides a method in a base class, to be used with 2706/// CXXRecordDecl::lookupInBases(). 2707static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2708 CXXBasePath &Path, 2709 void *UserData) { 2710 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2711 2712 FindOverriddenMethodData *Data 2713 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2714 2715 DeclarationName Name = Data->Method->getDeclName(); 2716 2717 // FIXME: Do we care about other names here too? 2718 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2719 // We really want to find the base class constructor here. 2720 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2721 CanQualType CT = Data->S->Context.getCanonicalType(T); 2722 2723 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2724 } 2725 2726 for (Path.Decls = BaseRecord->lookup(Name); 2727 Path.Decls.first != Path.Decls.second; 2728 ++Path.Decls.first) { 2729 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2730 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2731 return true; 2732 } 2733 } 2734 2735 return false; 2736} 2737 2738/// AddOverriddenMethods - See if a method overrides any in the base classes, 2739/// and if so, check that it's a valid override and remember it. 2740void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2741 // Look for virtual methods in base classes that this method might override. 2742 CXXBasePaths Paths; 2743 FindOverriddenMethodData Data; 2744 Data.Method = MD; 2745 Data.S = this; 2746 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2747 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2748 E = Paths.found_decls_end(); I != E; ++I) { 2749 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2750 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2751 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2752 !CheckOverridingFunctionAttributes(MD, OldMD)) 2753 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2754 } 2755 } 2756 } 2757} 2758 2759NamedDecl* 2760Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2761 QualType R, TypeSourceInfo *TInfo, 2762 LookupResult &Previous, 2763 MultiTemplateParamsArg TemplateParamLists, 2764 bool IsFunctionDefinition, bool &Redeclaration) { 2765 assert(R.getTypePtr()->isFunctionType()); 2766 2767 DeclarationName Name = GetNameForDeclarator(D); 2768 FunctionDecl::StorageClass SC = FunctionDecl::None; 2769 switch (D.getDeclSpec().getStorageClassSpec()) { 2770 default: assert(0 && "Unknown storage class!"); 2771 case DeclSpec::SCS_auto: 2772 case DeclSpec::SCS_register: 2773 case DeclSpec::SCS_mutable: 2774 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2775 diag::err_typecheck_sclass_func); 2776 D.setInvalidType(); 2777 break; 2778 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2779 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2780 case DeclSpec::SCS_static: { 2781 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2782 // C99 6.7.1p5: 2783 // The declaration of an identifier for a function that has 2784 // block scope shall have no explicit storage-class specifier 2785 // other than extern 2786 // See also (C++ [dcl.stc]p4). 2787 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2788 diag::err_static_block_func); 2789 SC = FunctionDecl::None; 2790 } else 2791 SC = FunctionDecl::Static; 2792 break; 2793 } 2794 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2795 } 2796 2797 if (D.getDeclSpec().isThreadSpecified()) 2798 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2799 2800 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2801 bool isInline = D.getDeclSpec().isInlineSpecified(); 2802 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2803 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2804 2805 // Check that the return type is not an abstract class type. 2806 // For record types, this is done by the AbstractClassUsageDiagnoser once 2807 // the class has been completely parsed. 2808 if (!DC->isRecord() && 2809 RequireNonAbstractType(D.getIdentifierLoc(), 2810 R->getAs<FunctionType>()->getResultType(), 2811 diag::err_abstract_type_in_decl, 2812 AbstractReturnType)) 2813 D.setInvalidType(); 2814 2815 // Do not allow returning a objc interface by-value. 2816 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2817 Diag(D.getIdentifierLoc(), 2818 diag::err_object_cannot_be_passed_returned_by_value) << 0 2819 << R->getAs<FunctionType>()->getResultType(); 2820 D.setInvalidType(); 2821 } 2822 2823 bool isVirtualOkay = false; 2824 FunctionDecl *NewFD; 2825 2826 if (isFriend) { 2827 // C++ [class.friend]p5 2828 // A function can be defined in a friend declaration of a 2829 // class . . . . Such a function is implicitly inline. 2830 isInline |= IsFunctionDefinition; 2831 } 2832 2833 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2834 // This is a C++ constructor declaration. 2835 assert(DC->isRecord() && 2836 "Constructors can only be declared in a member context"); 2837 2838 R = CheckConstructorDeclarator(D, R, SC); 2839 2840 // Create the new declaration 2841 NewFD = CXXConstructorDecl::Create(Context, 2842 cast<CXXRecordDecl>(DC), 2843 D.getIdentifierLoc(), Name, R, TInfo, 2844 isExplicit, isInline, 2845 /*isImplicitlyDeclared=*/false); 2846 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2847 // This is a C++ destructor declaration. 2848 if (DC->isRecord()) { 2849 R = CheckDestructorDeclarator(D, SC); 2850 2851 NewFD = CXXDestructorDecl::Create(Context, 2852 cast<CXXRecordDecl>(DC), 2853 D.getIdentifierLoc(), Name, R, 2854 isInline, 2855 /*isImplicitlyDeclared=*/false); 2856 NewFD->setTypeSourceInfo(TInfo); 2857 2858 isVirtualOkay = true; 2859 } else { 2860 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2861 2862 // Create a FunctionDecl to satisfy the function definition parsing 2863 // code path. 2864 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2865 Name, R, TInfo, SC, isInline, 2866 /*hasPrototype=*/true); 2867 D.setInvalidType(); 2868 } 2869 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2870 if (!DC->isRecord()) { 2871 Diag(D.getIdentifierLoc(), 2872 diag::err_conv_function_not_member); 2873 return 0; 2874 } 2875 2876 CheckConversionDeclarator(D, R, SC); 2877 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2878 D.getIdentifierLoc(), Name, R, TInfo, 2879 isInline, isExplicit); 2880 2881 isVirtualOkay = true; 2882 } else if (DC->isRecord()) { 2883 // If the of the function is the same as the name of the record, then this 2884 // must be an invalid constructor that has a return type. 2885 // (The parser checks for a return type and makes the declarator a 2886 // constructor if it has no return type). 2887 // must have an invalid constructor that has a return type 2888 if (Name.getAsIdentifierInfo() && 2889 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2890 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2891 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2892 << SourceRange(D.getIdentifierLoc()); 2893 return 0; 2894 } 2895 2896 bool isStatic = SC == FunctionDecl::Static; 2897 2898 // [class.free]p1: 2899 // Any allocation function for a class T is a static member 2900 // (even if not explicitly declared static). 2901 if (Name.getCXXOverloadedOperator() == OO_New || 2902 Name.getCXXOverloadedOperator() == OO_Array_New) 2903 isStatic = true; 2904 2905 // [class.free]p6 Any deallocation function for a class X is a static member 2906 // (even if not explicitly declared static). 2907 if (Name.getCXXOverloadedOperator() == OO_Delete || 2908 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2909 isStatic = true; 2910 2911 // This is a C++ method declaration. 2912 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2913 D.getIdentifierLoc(), Name, R, TInfo, 2914 isStatic, isInline); 2915 2916 isVirtualOkay = !isStatic; 2917 } else { 2918 // Determine whether the function was written with a 2919 // prototype. This true when: 2920 // - we're in C++ (where every function has a prototype), 2921 // - there is a prototype in the declarator, or 2922 // - the type R of the function is some kind of typedef or other reference 2923 // to a type name (which eventually refers to a function type). 2924 bool HasPrototype = 2925 getLangOptions().CPlusPlus || 2926 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2927 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2928 2929 NewFD = FunctionDecl::Create(Context, DC, 2930 D.getIdentifierLoc(), 2931 Name, R, TInfo, SC, isInline, HasPrototype); 2932 } 2933 2934 if (D.isInvalidType()) 2935 NewFD->setInvalidDecl(); 2936 2937 SetNestedNameSpecifier(NewFD, D); 2938 2939 // Set the lexical context. If the declarator has a C++ 2940 // scope specifier, or is the object of a friend declaration, the 2941 // lexical context will be different from the semantic context. 2942 NewFD->setLexicalDeclContext(CurContext); 2943 2944 // Match up the template parameter lists with the scope specifier, then 2945 // determine whether we have a template or a template specialization. 2946 FunctionTemplateDecl *FunctionTemplate = 0; 2947 bool isExplicitSpecialization = false; 2948 bool isFunctionTemplateSpecialization = false; 2949 if (TemplateParameterList *TemplateParams 2950 = MatchTemplateParametersToScopeSpecifier( 2951 D.getDeclSpec().getSourceRange().getBegin(), 2952 D.getCXXScopeSpec(), 2953 (TemplateParameterList**)TemplateParamLists.get(), 2954 TemplateParamLists.size(), 2955 isFriend, 2956 isExplicitSpecialization)) { 2957 if (TemplateParams->size() > 0) { 2958 // This is a function template 2959 2960 // Check that we can declare a template here. 2961 if (CheckTemplateDeclScope(S, TemplateParams)) 2962 return 0; 2963 2964 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2965 NewFD->getLocation(), 2966 Name, TemplateParams, 2967 NewFD); 2968 FunctionTemplate->setLexicalDeclContext(CurContext); 2969 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2970 } else { 2971 // This is a function template specialization. 2972 isFunctionTemplateSpecialization = true; 2973 2974 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 2975 if (isFriend && isFunctionTemplateSpecialization) { 2976 // We want to remove the "template<>", found here. 2977 SourceRange RemoveRange = TemplateParams->getSourceRange(); 2978 2979 // If we remove the template<> and the name is not a 2980 // template-id, we're actually silently creating a problem: 2981 // the friend declaration will refer to an untemplated decl, 2982 // and clearly the user wants a template specialization. So 2983 // we need to insert '<>' after the name. 2984 SourceLocation InsertLoc; 2985 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 2986 InsertLoc = D.getName().getSourceRange().getEnd(); 2987 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 2988 } 2989 2990 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 2991 << Name << RemoveRange 2992 << FixItHint::CreateRemoval(RemoveRange) 2993 << FixItHint::CreateInsertion(InsertLoc, "<>"); 2994 } 2995 } 2996 2997 // FIXME: Free this memory properly. 2998 TemplateParamLists.release(); 2999 } 3000 3001 // C++ [dcl.fct.spec]p5: 3002 // The virtual specifier shall only be used in declarations of 3003 // nonstatic class member functions that appear within a 3004 // member-specification of a class declaration; see 10.3. 3005 // 3006 if (isVirtual && !NewFD->isInvalidDecl()) { 3007 if (!isVirtualOkay) { 3008 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3009 diag::err_virtual_non_function); 3010 } else if (!CurContext->isRecord()) { 3011 // 'virtual' was specified outside of the class. 3012 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3013 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3014 } else { 3015 // Okay: Add virtual to the method. 3016 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3017 CurClass->setMethodAsVirtual(NewFD); 3018 } 3019 } 3020 3021 // C++ [dcl.fct.spec]p6: 3022 // The explicit specifier shall be used only in the declaration of a 3023 // constructor or conversion function within its class definition; see 12.3.1 3024 // and 12.3.2. 3025 if (isExplicit && !NewFD->isInvalidDecl()) { 3026 if (!CurContext->isRecord()) { 3027 // 'explicit' was specified outside of the class. 3028 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3029 diag::err_explicit_out_of_class) 3030 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3031 } else if (!isa<CXXConstructorDecl>(NewFD) && 3032 !isa<CXXConversionDecl>(NewFD)) { 3033 // 'explicit' was specified on a function that wasn't a constructor 3034 // or conversion function. 3035 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3036 diag::err_explicit_non_ctor_or_conv_function) 3037 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3038 } 3039 } 3040 3041 // Filter out previous declarations that don't match the scope. 3042 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3043 3044 if (isFriend) { 3045 // DC is the namespace in which the function is being declared. 3046 assert((DC->isFileContext() || !Previous.empty()) && 3047 "previously-undeclared friend function being created " 3048 "in a non-namespace context"); 3049 3050 // For now, claim that the objects have no previous declaration. 3051 if (FunctionTemplate) { 3052 FunctionTemplate->setObjectOfFriendDecl(false); 3053 FunctionTemplate->setAccess(AS_public); 3054 } 3055 NewFD->setObjectOfFriendDecl(false); 3056 NewFD->setAccess(AS_public); 3057 } 3058 3059 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3060 !CurContext->isRecord()) { 3061 // C++ [class.static]p1: 3062 // A data or function member of a class may be declared static 3063 // in a class definition, in which case it is a static member of 3064 // the class. 3065 3066 // Complain about the 'static' specifier if it's on an out-of-line 3067 // member function definition. 3068 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3069 diag::err_static_out_of_line) 3070 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3071 } 3072 3073 // Handle GNU asm-label extension (encoded as an attribute). 3074 if (Expr *E = (Expr*) D.getAsmLabel()) { 3075 // The parser guarantees this is a string. 3076 StringLiteral *SE = cast<StringLiteral>(E); 3077 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3078 } 3079 3080 // Copy the parameter declarations from the declarator D to the function 3081 // declaration NewFD, if they are available. First scavenge them into Params. 3082 llvm::SmallVector<ParmVarDecl*, 16> Params; 3083 if (D.getNumTypeObjects() > 0) { 3084 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3085 3086 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3087 // function that takes no arguments, not a function that takes a 3088 // single void argument. 3089 // We let through "const void" here because Sema::GetTypeForDeclarator 3090 // already checks for that case. 3091 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3092 FTI.ArgInfo[0].Param && 3093 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3094 // Empty arg list, don't push any params. 3095 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3096 3097 // In C++, the empty parameter-type-list must be spelled "void"; a 3098 // typedef of void is not permitted. 3099 if (getLangOptions().CPlusPlus && 3100 Param->getType().getUnqualifiedType() != Context.VoidTy) 3101 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3102 // FIXME: Leaks decl? 3103 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3104 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3105 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3106 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3107 Param->setDeclContext(NewFD); 3108 Params.push_back(Param); 3109 3110 if (Param->isInvalidDecl()) 3111 NewFD->setInvalidDecl(); 3112 } 3113 } 3114 3115 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3116 // When we're declaring a function with a typedef, typeof, etc as in the 3117 // following example, we'll need to synthesize (unnamed) 3118 // parameters for use in the declaration. 3119 // 3120 // @code 3121 // typedef void fn(int); 3122 // fn f; 3123 // @endcode 3124 3125 // Synthesize a parameter for each argument type. 3126 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3127 AE = FT->arg_type_end(); AI != AE; ++AI) { 3128 ParmVarDecl *Param = ParmVarDecl::Create(Context, NewFD, 3129 SourceLocation(), 0, 3130 *AI, /*TInfo=*/0, 3131 VarDecl::None, 0); 3132 Param->setImplicit(); 3133 Params.push_back(Param); 3134 } 3135 } else { 3136 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3137 "Should not need args for typedef of non-prototype fn"); 3138 } 3139 // Finally, we know we have the right number of parameters, install them. 3140 NewFD->setParams(Params.data(), Params.size()); 3141 3142 // If the declarator is a template-id, translate the parser's template 3143 // argument list into our AST format. 3144 bool HasExplicitTemplateArgs = false; 3145 TemplateArgumentListInfo TemplateArgs; 3146 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3147 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3148 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3149 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3150 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3151 TemplateId->getTemplateArgs(), 3152 TemplateId->NumArgs); 3153 translateTemplateArguments(TemplateArgsPtr, 3154 TemplateArgs); 3155 TemplateArgsPtr.release(); 3156 3157 HasExplicitTemplateArgs = true; 3158 3159 if (FunctionTemplate) { 3160 // FIXME: Diagnose function template with explicit template 3161 // arguments. 3162 HasExplicitTemplateArgs = false; 3163 } else if (!isFunctionTemplateSpecialization && 3164 !D.getDeclSpec().isFriendSpecified()) { 3165 // We have encountered something that the user meant to be a 3166 // specialization (because it has explicitly-specified template 3167 // arguments) but that was not introduced with a "template<>" (or had 3168 // too few of them). 3169 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3170 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3171 << FixItHint::CreateInsertion( 3172 D.getDeclSpec().getSourceRange().getBegin(), 3173 "template<> "); 3174 isFunctionTemplateSpecialization = true; 3175 } else { 3176 // "friend void foo<>(int);" is an implicit specialization decl. 3177 isFunctionTemplateSpecialization = true; 3178 } 3179 } else if (isFriend && isFunctionTemplateSpecialization) { 3180 // This combination is only possible in a recovery case; the user 3181 // wrote something like: 3182 // template <> friend void foo(int); 3183 // which we're recovering from as if the user had written: 3184 // friend void foo<>(int); 3185 // Go ahead and fake up a template id. 3186 HasExplicitTemplateArgs = true; 3187 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3188 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3189 } 3190 3191 // If it's a friend (and only if it's a friend), it's possible 3192 // that either the specialized function type or the specialized 3193 // template is dependent, and therefore matching will fail. In 3194 // this case, don't check the specialization yet. 3195 if (isFunctionTemplateSpecialization && isFriend && 3196 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3197 assert(HasExplicitTemplateArgs && 3198 "friend function specialization without template args"); 3199 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3200 Previous)) 3201 NewFD->setInvalidDecl(); 3202 } else if (isFunctionTemplateSpecialization) { 3203 if (CheckFunctionTemplateSpecialization(NewFD, 3204 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3205 Previous)) 3206 NewFD->setInvalidDecl(); 3207 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3208 if (CheckMemberSpecialization(NewFD, Previous)) 3209 NewFD->setInvalidDecl(); 3210 } 3211 3212 // Perform semantic checking on the function declaration. 3213 bool OverloadableAttrRequired = false; // FIXME: HACK! 3214 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3215 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3216 3217 assert((NewFD->isInvalidDecl() || !Redeclaration || 3218 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3219 "previous declaration set still overloaded"); 3220 3221 if (isFriend && Redeclaration) { 3222 AccessSpecifier Access = AS_public; 3223 if (!NewFD->isInvalidDecl()) 3224 Access = NewFD->getPreviousDeclaration()->getAccess(); 3225 3226 if (FunctionTemplate) { 3227 FunctionTemplate->setObjectOfFriendDecl(true); 3228 FunctionTemplate->setAccess(Access); 3229 } else { 3230 NewFD->setObjectOfFriendDecl(true); 3231 } 3232 NewFD->setAccess(Access); 3233 } 3234 3235 // If we have a function template, check the template parameter 3236 // list. This will check and merge default template arguments. 3237 if (FunctionTemplate) { 3238 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3239 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3240 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3241 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3242 : TPC_FunctionTemplate); 3243 } 3244 3245 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3246 // Fake up an access specifier if it's supposed to be a class member. 3247 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3248 NewFD->setAccess(AS_public); 3249 3250 // An out-of-line member function declaration must also be a 3251 // definition (C++ [dcl.meaning]p1). 3252 // Note that this is not the case for explicit specializations of 3253 // function templates or member functions of class templates, per 3254 // C++ [temp.expl.spec]p2. 3255 if (!IsFunctionDefinition && !isFriend && 3256 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3257 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3258 << D.getCXXScopeSpec().getRange(); 3259 NewFD->setInvalidDecl(); 3260 } else if (!Redeclaration && 3261 !(isFriend && CurContext->isDependentContext())) { 3262 // The user tried to provide an out-of-line definition for a 3263 // function that is a member of a class or namespace, but there 3264 // was no such member function declared (C++ [class.mfct]p2, 3265 // C++ [namespace.memdef]p2). For example: 3266 // 3267 // class X { 3268 // void f() const; 3269 // }; 3270 // 3271 // void X::f() { } // ill-formed 3272 // 3273 // Complain about this problem, and attempt to suggest close 3274 // matches (e.g., those that differ only in cv-qualifiers and 3275 // whether the parameter types are references). 3276 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3277 << Name << DC << D.getCXXScopeSpec().getRange(); 3278 NewFD->setInvalidDecl(); 3279 3280 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3281 ForRedeclaration); 3282 LookupQualifiedName(Prev, DC); 3283 assert(!Prev.isAmbiguous() && 3284 "Cannot have an ambiguity in previous-declaration lookup"); 3285 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3286 Func != FuncEnd; ++Func) { 3287 if (isa<FunctionDecl>(*Func) && 3288 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3289 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3290 } 3291 } 3292 } 3293 3294 // Handle attributes. We need to have merged decls when handling attributes 3295 // (for example to check for conflicts, etc). 3296 // FIXME: This needs to happen before we merge declarations. Then, 3297 // let attribute merging cope with attribute conflicts. 3298 ProcessDeclAttributes(S, NewFD, D); 3299 3300 // attributes declared post-definition are currently ignored 3301 if (Redeclaration && Previous.isSingleResult()) { 3302 const FunctionDecl *Def; 3303 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3304 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3305 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3306 Diag(Def->getLocation(), diag::note_previous_definition); 3307 } 3308 } 3309 3310 AddKnownFunctionAttributes(NewFD); 3311 3312 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3313 // If a function name is overloadable in C, then every function 3314 // with that name must be marked "overloadable". 3315 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3316 << Redeclaration << NewFD; 3317 if (!Previous.empty()) 3318 Diag(Previous.getRepresentativeDecl()->getLocation(), 3319 diag::note_attribute_overloadable_prev_overload); 3320 NewFD->addAttr(::new (Context) OverloadableAttr()); 3321 } 3322 3323 // If this is a locally-scoped extern C function, update the 3324 // map of such names. 3325 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3326 && !NewFD->isInvalidDecl()) 3327 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3328 3329 // Set this FunctionDecl's range up to the right paren. 3330 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3331 3332 if (FunctionTemplate && NewFD->isInvalidDecl()) 3333 FunctionTemplate->setInvalidDecl(); 3334 3335 if (FunctionTemplate) 3336 return FunctionTemplate; 3337 3338 3339 // Keep track of static, non-inlined function definitions that 3340 // have not been used. We will warn later. 3341 // FIXME: Also include static functions declared but not defined. 3342 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3343 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3344 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3345 && !NewFD->hasAttr<ConstructorAttr>() 3346 && !NewFD->hasAttr<DestructorAttr>()) 3347 UnusedStaticFuncs.push_back(NewFD); 3348 3349 return NewFD; 3350} 3351 3352/// \brief Perform semantic checking of a new function declaration. 3353/// 3354/// Performs semantic analysis of the new function declaration 3355/// NewFD. This routine performs all semantic checking that does not 3356/// require the actual declarator involved in the declaration, and is 3357/// used both for the declaration of functions as they are parsed 3358/// (called via ActOnDeclarator) and for the declaration of functions 3359/// that have been instantiated via C++ template instantiation (called 3360/// via InstantiateDecl). 3361/// 3362/// \param IsExplicitSpecialiation whether this new function declaration is 3363/// an explicit specialization of the previous declaration. 3364/// 3365/// This sets NewFD->isInvalidDecl() to true if there was an error. 3366void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3367 LookupResult &Previous, 3368 bool IsExplicitSpecialization, 3369 bool &Redeclaration, 3370 bool &OverloadableAttrRequired) { 3371 // If NewFD is already known erroneous, don't do any of this checking. 3372 if (NewFD->isInvalidDecl()) 3373 return; 3374 3375 if (NewFD->getResultType()->isVariablyModifiedType()) { 3376 // Functions returning a variably modified type violate C99 6.7.5.2p2 3377 // because all functions have linkage. 3378 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3379 return NewFD->setInvalidDecl(); 3380 } 3381 3382 if (NewFD->isMain()) 3383 CheckMain(NewFD); 3384 3385 // Check for a previous declaration of this name. 3386 if (Previous.empty() && NewFD->isExternC()) { 3387 // Since we did not find anything by this name and we're declaring 3388 // an extern "C" function, look for a non-visible extern "C" 3389 // declaration with the same name. 3390 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3391 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3392 if (Pos != LocallyScopedExternalDecls.end()) 3393 Previous.addDecl(Pos->second); 3394 } 3395 3396 // Merge or overload the declaration with an existing declaration of 3397 // the same name, if appropriate. 3398 if (!Previous.empty()) { 3399 // Determine whether NewFD is an overload of PrevDecl or 3400 // a declaration that requires merging. If it's an overload, 3401 // there's no more work to do here; we'll just add the new 3402 // function to the scope. 3403 3404 NamedDecl *OldDecl = 0; 3405 if (!AllowOverloadingOfFunction(Previous, Context)) { 3406 Redeclaration = true; 3407 OldDecl = Previous.getFoundDecl(); 3408 } else { 3409 if (!getLangOptions().CPlusPlus) { 3410 OverloadableAttrRequired = true; 3411 3412 // Functions marked "overloadable" must have a prototype (that 3413 // we can't get through declaration merging). 3414 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3415 Diag(NewFD->getLocation(), 3416 diag::err_attribute_overloadable_no_prototype) 3417 << NewFD; 3418 Redeclaration = true; 3419 3420 // Turn this into a variadic function with no parameters. 3421 QualType R = Context.getFunctionType( 3422 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3423 0, 0, true, 0, false, false, 0, 0, 3424 FunctionType::ExtInfo()); 3425 NewFD->setType(R); 3426 return NewFD->setInvalidDecl(); 3427 } 3428 } 3429 3430 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3431 case Ovl_Match: 3432 Redeclaration = true; 3433 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3434 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3435 Redeclaration = false; 3436 } 3437 break; 3438 3439 case Ovl_NonFunction: 3440 Redeclaration = true; 3441 break; 3442 3443 case Ovl_Overload: 3444 Redeclaration = false; 3445 break; 3446 } 3447 } 3448 3449 if (Redeclaration) { 3450 // NewFD and OldDecl represent declarations that need to be 3451 // merged. 3452 if (MergeFunctionDecl(NewFD, OldDecl)) 3453 return NewFD->setInvalidDecl(); 3454 3455 Previous.clear(); 3456 Previous.addDecl(OldDecl); 3457 3458 if (FunctionTemplateDecl *OldTemplateDecl 3459 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3460 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3461 FunctionTemplateDecl *NewTemplateDecl 3462 = NewFD->getDescribedFunctionTemplate(); 3463 assert(NewTemplateDecl && "Template/non-template mismatch"); 3464 if (CXXMethodDecl *Method 3465 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3466 Method->setAccess(OldTemplateDecl->getAccess()); 3467 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3468 } 3469 3470 // If this is an explicit specialization of a member that is a function 3471 // template, mark it as a member specialization. 3472 if (IsExplicitSpecialization && 3473 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3474 NewTemplateDecl->setMemberSpecialization(); 3475 assert(OldTemplateDecl->isMemberSpecialization()); 3476 } 3477 } else { 3478 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3479 NewFD->setAccess(OldDecl->getAccess()); 3480 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3481 } 3482 } 3483 } 3484 3485 // Semantic checking for this function declaration (in isolation). 3486 if (getLangOptions().CPlusPlus) { 3487 // C++-specific checks. 3488 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3489 CheckConstructor(Constructor); 3490 } else if (CXXDestructorDecl *Destructor = 3491 dyn_cast<CXXDestructorDecl>(NewFD)) { 3492 CXXRecordDecl *Record = Destructor->getParent(); 3493 QualType ClassType = Context.getTypeDeclType(Record); 3494 3495 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3496 // type is dependent? Both gcc and edg can handle that. 3497 if (!ClassType->isDependentType()) { 3498 DeclarationName Name 3499 = Context.DeclarationNames.getCXXDestructorName( 3500 Context.getCanonicalType(ClassType)); 3501 if (NewFD->getDeclName() != Name) { 3502 Diag(NewFD->getLocation(), diag::err_destructor_name); 3503 return NewFD->setInvalidDecl(); 3504 } 3505 } 3506 3507 Record->setUserDeclaredDestructor(true); 3508 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3509 // user-defined destructor. 3510 Record->setPOD(false); 3511 3512 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3513 // declared destructor. 3514 // FIXME: C++0x: don't do this for "= default" destructors 3515 Record->setHasTrivialDestructor(false); 3516 } else if (CXXConversionDecl *Conversion 3517 = dyn_cast<CXXConversionDecl>(NewFD)) { 3518 ActOnConversionDeclarator(Conversion); 3519 } 3520 3521 // Find any virtual functions that this function overrides. 3522 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3523 if (!Method->isFunctionTemplateSpecialization() && 3524 !Method->getDescribedFunctionTemplate()) 3525 AddOverriddenMethods(Method->getParent(), Method); 3526 } 3527 3528 // Additional checks for the destructor; make sure we do this after we 3529 // figure out whether the destructor is virtual. 3530 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3531 if (!Destructor->getParent()->isDependentType()) 3532 CheckDestructor(Destructor); 3533 3534 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3535 if (NewFD->isOverloadedOperator() && 3536 CheckOverloadedOperatorDeclaration(NewFD)) 3537 return NewFD->setInvalidDecl(); 3538 3539 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3540 if (NewFD->getLiteralIdentifier() && 3541 CheckLiteralOperatorDeclaration(NewFD)) 3542 return NewFD->setInvalidDecl(); 3543 3544 // In C++, check default arguments now that we have merged decls. Unless 3545 // the lexical context is the class, because in this case this is done 3546 // during delayed parsing anyway. 3547 if (!CurContext->isRecord()) 3548 CheckCXXDefaultArguments(NewFD); 3549 } 3550} 3551 3552void Sema::CheckMain(FunctionDecl* FD) { 3553 // C++ [basic.start.main]p3: A program that declares main to be inline 3554 // or static is ill-formed. 3555 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3556 // shall not appear in a declaration of main. 3557 // static main is not an error under C99, but we should warn about it. 3558 bool isInline = FD->isInlineSpecified(); 3559 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3560 if (isInline || isStatic) { 3561 unsigned diagID = diag::warn_unusual_main_decl; 3562 if (isInline || getLangOptions().CPlusPlus) 3563 diagID = diag::err_unusual_main_decl; 3564 3565 int which = isStatic + (isInline << 1) - 1; 3566 Diag(FD->getLocation(), diagID) << which; 3567 } 3568 3569 QualType T = FD->getType(); 3570 assert(T->isFunctionType() && "function decl is not of function type"); 3571 const FunctionType* FT = T->getAs<FunctionType>(); 3572 3573 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3574 // TODO: add a replacement fixit to turn the return type into 'int'. 3575 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3576 FD->setInvalidDecl(true); 3577 } 3578 3579 // Treat protoless main() as nullary. 3580 if (isa<FunctionNoProtoType>(FT)) return; 3581 3582 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3583 unsigned nparams = FTP->getNumArgs(); 3584 assert(FD->getNumParams() == nparams); 3585 3586 bool HasExtraParameters = (nparams > 3); 3587 3588 // Darwin passes an undocumented fourth argument of type char**. If 3589 // other platforms start sprouting these, the logic below will start 3590 // getting shifty. 3591 if (nparams == 4 && 3592 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3593 HasExtraParameters = false; 3594 3595 if (HasExtraParameters) { 3596 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3597 FD->setInvalidDecl(true); 3598 nparams = 3; 3599 } 3600 3601 // FIXME: a lot of the following diagnostics would be improved 3602 // if we had some location information about types. 3603 3604 QualType CharPP = 3605 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3606 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3607 3608 for (unsigned i = 0; i < nparams; ++i) { 3609 QualType AT = FTP->getArgType(i); 3610 3611 bool mismatch = true; 3612 3613 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3614 mismatch = false; 3615 else if (Expected[i] == CharPP) { 3616 // As an extension, the following forms are okay: 3617 // char const ** 3618 // char const * const * 3619 // char * const * 3620 3621 QualifierCollector qs; 3622 const PointerType* PT; 3623 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3624 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3625 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3626 qs.removeConst(); 3627 mismatch = !qs.empty(); 3628 } 3629 } 3630 3631 if (mismatch) { 3632 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3633 // TODO: suggest replacing given type with expected type 3634 FD->setInvalidDecl(true); 3635 } 3636 } 3637 3638 if (nparams == 1 && !FD->isInvalidDecl()) { 3639 Diag(FD->getLocation(), diag::warn_main_one_arg); 3640 } 3641} 3642 3643bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3644 // FIXME: Need strict checking. In C89, we need to check for 3645 // any assignment, increment, decrement, function-calls, or 3646 // commas outside of a sizeof. In C99, it's the same list, 3647 // except that the aforementioned are allowed in unevaluated 3648 // expressions. Everything else falls under the 3649 // "may accept other forms of constant expressions" exception. 3650 // (We never end up here for C++, so the constant expression 3651 // rules there don't matter.) 3652 if (Init->isConstantInitializer(Context)) 3653 return false; 3654 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3655 << Init->getSourceRange(); 3656 return true; 3657} 3658 3659void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3660 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3661} 3662 3663/// AddInitializerToDecl - Adds the initializer Init to the 3664/// declaration dcl. If DirectInit is true, this is C++ direct 3665/// initialization rather than copy initialization. 3666void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3667 Decl *RealDecl = dcl.getAs<Decl>(); 3668 // If there is no declaration, there was an error parsing it. Just ignore 3669 // the initializer. 3670 if (RealDecl == 0) 3671 return; 3672 3673 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3674 // With declarators parsed the way they are, the parser cannot 3675 // distinguish between a normal initializer and a pure-specifier. 3676 // Thus this grotesque test. 3677 IntegerLiteral *IL; 3678 Expr *Init = static_cast<Expr *>(init.get()); 3679 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3680 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3681 CheckPureMethod(Method, Init->getSourceRange()); 3682 else { 3683 Diag(Method->getLocation(), diag::err_member_function_initialization) 3684 << Method->getDeclName() << Init->getSourceRange(); 3685 Method->setInvalidDecl(); 3686 } 3687 return; 3688 } 3689 3690 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3691 if (!VDecl) { 3692 if (getLangOptions().CPlusPlus && 3693 RealDecl->getLexicalDeclContext()->isRecord() && 3694 isa<NamedDecl>(RealDecl)) 3695 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3696 << cast<NamedDecl>(RealDecl)->getDeclName(); 3697 else 3698 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3699 RealDecl->setInvalidDecl(); 3700 return; 3701 } 3702 3703 // A definition must end up with a complete type, which means it must be 3704 // complete with the restriction that an array type might be completed by the 3705 // initializer; note that later code assumes this restriction. 3706 QualType BaseDeclType = VDecl->getType(); 3707 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3708 BaseDeclType = Array->getElementType(); 3709 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3710 diag::err_typecheck_decl_incomplete_type)) { 3711 RealDecl->setInvalidDecl(); 3712 return; 3713 } 3714 3715 // The variable can not have an abstract class type. 3716 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3717 diag::err_abstract_type_in_decl, 3718 AbstractVariableType)) 3719 VDecl->setInvalidDecl(); 3720 3721 const VarDecl *Def; 3722 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3723 Diag(VDecl->getLocation(), diag::err_redefinition) 3724 << VDecl->getDeclName(); 3725 Diag(Def->getLocation(), diag::note_previous_definition); 3726 VDecl->setInvalidDecl(); 3727 return; 3728 } 3729 3730 // Take ownership of the expression, now that we're sure we have somewhere 3731 // to put it. 3732 Expr *Init = init.takeAs<Expr>(); 3733 assert(Init && "missing initializer"); 3734 3735 // Capture the variable that is being initialized and the style of 3736 // initialization. 3737 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3738 3739 // FIXME: Poor source location information. 3740 InitializationKind Kind 3741 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3742 Init->getLocStart(), 3743 Init->getLocEnd()) 3744 : InitializationKind::CreateCopy(VDecl->getLocation(), 3745 Init->getLocStart()); 3746 3747 // Get the decls type and save a reference for later, since 3748 // CheckInitializerTypes may change it. 3749 QualType DclT = VDecl->getType(), SavT = DclT; 3750 if (VDecl->isBlockVarDecl()) { 3751 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3752 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3753 VDecl->setInvalidDecl(); 3754 } else if (!VDecl->isInvalidDecl()) { 3755 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3756 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3757 MultiExprArg(*this, (void**)&Init, 1), 3758 &DclT); 3759 if (Result.isInvalid()) { 3760 VDecl->setInvalidDecl(); 3761 return; 3762 } 3763 3764 Init = Result.takeAs<Expr>(); 3765 3766 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3767 // Don't check invalid declarations to avoid emitting useless diagnostics. 3768 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3769 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3770 CheckForConstantInitializer(Init, DclT); 3771 } 3772 } 3773 } else if (VDecl->isStaticDataMember() && 3774 VDecl->getLexicalDeclContext()->isRecord()) { 3775 // This is an in-class initialization for a static data member, e.g., 3776 // 3777 // struct S { 3778 // static const int value = 17; 3779 // }; 3780 3781 // Attach the initializer 3782 VDecl->setInit(Init); 3783 3784 // C++ [class.mem]p4: 3785 // A member-declarator can contain a constant-initializer only 3786 // if it declares a static member (9.4) of const integral or 3787 // const enumeration type, see 9.4.2. 3788 QualType T = VDecl->getType(); 3789 if (!T->isDependentType() && 3790 (!Context.getCanonicalType(T).isConstQualified() || 3791 !T->isIntegralType())) { 3792 Diag(VDecl->getLocation(), diag::err_member_initialization) 3793 << VDecl->getDeclName() << Init->getSourceRange(); 3794 VDecl->setInvalidDecl(); 3795 } else { 3796 // C++ [class.static.data]p4: 3797 // If a static data member is of const integral or const 3798 // enumeration type, its declaration in the class definition 3799 // can specify a constant-initializer which shall be an 3800 // integral constant expression (5.19). 3801 if (!Init->isTypeDependent() && 3802 !Init->getType()->isIntegralType()) { 3803 // We have a non-dependent, non-integral or enumeration type. 3804 Diag(Init->getSourceRange().getBegin(), 3805 diag::err_in_class_initializer_non_integral_type) 3806 << Init->getType() << Init->getSourceRange(); 3807 VDecl->setInvalidDecl(); 3808 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3809 // Check whether the expression is a constant expression. 3810 llvm::APSInt Value; 3811 SourceLocation Loc; 3812 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3813 Diag(Loc, diag::err_in_class_initializer_non_constant) 3814 << Init->getSourceRange(); 3815 VDecl->setInvalidDecl(); 3816 } else if (!VDecl->getType()->isDependentType()) 3817 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3818 } 3819 } 3820 } else if (VDecl->isFileVarDecl()) { 3821 if (VDecl->getStorageClass() == VarDecl::Extern) 3822 Diag(VDecl->getLocation(), diag::warn_extern_init); 3823 if (!VDecl->isInvalidDecl()) { 3824 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3825 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3826 MultiExprArg(*this, (void**)&Init, 1), 3827 &DclT); 3828 if (Result.isInvalid()) { 3829 VDecl->setInvalidDecl(); 3830 return; 3831 } 3832 3833 Init = Result.takeAs<Expr>(); 3834 } 3835 3836 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3837 // Don't check invalid declarations to avoid emitting useless diagnostics. 3838 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3839 // C99 6.7.8p4. All file scoped initializers need to be constant. 3840 CheckForConstantInitializer(Init, DclT); 3841 } 3842 } 3843 // If the type changed, it means we had an incomplete type that was 3844 // completed by the initializer. For example: 3845 // int ary[] = { 1, 3, 5 }; 3846 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3847 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3848 VDecl->setType(DclT); 3849 Init->setType(DclT); 3850 } 3851 3852 Init = MaybeCreateCXXExprWithTemporaries(Init); 3853 // Attach the initializer to the decl. 3854 VDecl->setInit(Init); 3855 3856 if (getLangOptions().CPlusPlus) { 3857 // Make sure we mark the destructor as used if necessary. 3858 QualType InitType = VDecl->getType(); 3859 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3860 InitType = Context.getBaseElementType(Array); 3861 if (const RecordType *Record = InitType->getAs<RecordType>()) 3862 FinalizeVarWithDestructor(VDecl, Record); 3863 } 3864 3865 return; 3866} 3867 3868/// ActOnInitializerError - Given that there was an error parsing an 3869/// initializer for the given declaration, try to return to some form 3870/// of sanity. 3871void Sema::ActOnInitializerError(DeclPtrTy dcl) { 3872 // Our main concern here is re-establishing invariants like "a 3873 // variable's type is either dependent or complete". 3874 Decl *D = dcl.getAs<Decl>(); 3875 if (!D || D->isInvalidDecl()) return; 3876 3877 VarDecl *VD = dyn_cast<VarDecl>(D); 3878 if (!VD) return; 3879 3880 QualType Ty = VD->getType(); 3881 if (Ty->isDependentType()) return; 3882 3883 // Require a complete type. 3884 if (RequireCompleteType(VD->getLocation(), 3885 Context.getBaseElementType(Ty), 3886 diag::err_typecheck_decl_incomplete_type)) { 3887 VD->setInvalidDecl(); 3888 return; 3889 } 3890 3891 // Require an abstract type. 3892 if (RequireNonAbstractType(VD->getLocation(), Ty, 3893 diag::err_abstract_type_in_decl, 3894 AbstractVariableType)) { 3895 VD->setInvalidDecl(); 3896 return; 3897 } 3898 3899 // Don't bother complaining about constructors or destructors, 3900 // though. 3901} 3902 3903void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3904 bool TypeContainsUndeducedAuto) { 3905 Decl *RealDecl = dcl.getAs<Decl>(); 3906 3907 // If there is no declaration, there was an error parsing it. Just ignore it. 3908 if (RealDecl == 0) 3909 return; 3910 3911 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3912 QualType Type = Var->getType(); 3913 3914 // C++0x [dcl.spec.auto]p3 3915 if (TypeContainsUndeducedAuto) { 3916 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3917 << Var->getDeclName() << Type; 3918 Var->setInvalidDecl(); 3919 return; 3920 } 3921 3922 switch (Var->isThisDeclarationADefinition()) { 3923 case VarDecl::Definition: 3924 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 3925 break; 3926 3927 // We have an out-of-line definition of a static data member 3928 // that has an in-class initializer, so we type-check this like 3929 // a declaration. 3930 // 3931 // Fall through 3932 3933 case VarDecl::DeclarationOnly: 3934 // It's only a declaration. 3935 3936 // Block scope. C99 6.7p7: If an identifier for an object is 3937 // declared with no linkage (C99 6.2.2p6), the type for the 3938 // object shall be complete. 3939 if (!Type->isDependentType() && Var->isBlockVarDecl() && 3940 !Var->getLinkage() && !Var->isInvalidDecl() && 3941 RequireCompleteType(Var->getLocation(), Type, 3942 diag::err_typecheck_decl_incomplete_type)) 3943 Var->setInvalidDecl(); 3944 3945 // Make sure that the type is not abstract. 3946 if (!Type->isDependentType() && !Var->isInvalidDecl() && 3947 RequireNonAbstractType(Var->getLocation(), Type, 3948 diag::err_abstract_type_in_decl, 3949 AbstractVariableType)) 3950 Var->setInvalidDecl(); 3951 return; 3952 3953 case VarDecl::TentativeDefinition: 3954 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3955 // object that has file scope without an initializer, and without a 3956 // storage-class specifier or with the storage-class specifier "static", 3957 // constitutes a tentative definition. Note: A tentative definition with 3958 // external linkage is valid (C99 6.2.2p5). 3959 if (!Var->isInvalidDecl()) { 3960 if (const IncompleteArrayType *ArrayT 3961 = Context.getAsIncompleteArrayType(Type)) { 3962 if (RequireCompleteType(Var->getLocation(), 3963 ArrayT->getElementType(), 3964 diag::err_illegal_decl_array_incomplete_type)) 3965 Var->setInvalidDecl(); 3966 } else if (Var->getStorageClass() == VarDecl::Static) { 3967 // C99 6.9.2p3: If the declaration of an identifier for an object is 3968 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3969 // declared type shall not be an incomplete type. 3970 // NOTE: code such as the following 3971 // static struct s; 3972 // struct s { int a; }; 3973 // is accepted by gcc. Hence here we issue a warning instead of 3974 // an error and we do not invalidate the static declaration. 3975 // NOTE: to avoid multiple warnings, only check the first declaration. 3976 if (Var->getPreviousDeclaration() == 0) 3977 RequireCompleteType(Var->getLocation(), Type, 3978 diag::ext_typecheck_decl_incomplete_type); 3979 } 3980 } 3981 3982 // Record the tentative definition; we're done. 3983 if (!Var->isInvalidDecl()) 3984 TentativeDefinitions.push_back(Var); 3985 return; 3986 } 3987 3988 // Provide a specific diagnostic for uninitialized variable 3989 // definitions with incomplete array type. 3990 if (Type->isIncompleteArrayType()) { 3991 Diag(Var->getLocation(), 3992 diag::err_typecheck_incomplete_array_needs_initializer); 3993 Var->setInvalidDecl(); 3994 return; 3995 } 3996 3997 // Provide a specific diagnostic for uninitialized variable 3998 // definitions with reference type. 3999 if (Type->isReferenceType()) { 4000 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4001 << Var->getDeclName() 4002 << SourceRange(Var->getLocation(), Var->getLocation()); 4003 Var->setInvalidDecl(); 4004 return; 4005 } 4006 4007 // Do not attempt to type-check the default initializer for a 4008 // variable with dependent type. 4009 if (Type->isDependentType()) 4010 return; 4011 4012 if (Var->isInvalidDecl()) 4013 return; 4014 4015 if (RequireCompleteType(Var->getLocation(), 4016 Context.getBaseElementType(Type), 4017 diag::err_typecheck_decl_incomplete_type)) { 4018 Var->setInvalidDecl(); 4019 return; 4020 } 4021 4022 // The variable can not have an abstract class type. 4023 if (RequireNonAbstractType(Var->getLocation(), Type, 4024 diag::err_abstract_type_in_decl, 4025 AbstractVariableType)) { 4026 Var->setInvalidDecl(); 4027 return; 4028 } 4029 4030 const RecordType *Record 4031 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4032 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4033 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4034 // C++03 [dcl.init]p9: 4035 // If no initializer is specified for an object, and the 4036 // object is of (possibly cv-qualified) non-POD class type (or 4037 // array thereof), the object shall be default-initialized; if 4038 // the object is of const-qualified type, the underlying class 4039 // type shall have a user-declared default 4040 // constructor. Otherwise, if no initializer is specified for 4041 // a non- static object, the object and its subobjects, if 4042 // any, have an indeterminate initial value); if the object 4043 // or any of its subobjects are of const-qualified type, the 4044 // program is ill-formed. 4045 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4046 } else { 4047 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4048 InitializationKind Kind 4049 = InitializationKind::CreateDefault(Var->getLocation()); 4050 4051 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4052 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4053 MultiExprArg(*this, 0, 0)); 4054 if (Init.isInvalid()) 4055 Var->setInvalidDecl(); 4056 else if (Init.get()) 4057 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4058 } 4059 4060 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4061 FinalizeVarWithDestructor(Var, Record); 4062 } 4063} 4064 4065Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4066 DeclPtrTy *Group, 4067 unsigned NumDecls) { 4068 llvm::SmallVector<Decl*, 8> Decls; 4069 4070 if (DS.isTypeSpecOwned()) 4071 Decls.push_back((Decl*)DS.getTypeRep()); 4072 4073 for (unsigned i = 0; i != NumDecls; ++i) 4074 if (Decl *D = Group[i].getAs<Decl>()) 4075 Decls.push_back(D); 4076 4077 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4078 Decls.data(), Decls.size())); 4079} 4080 4081 4082/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4083/// to introduce parameters into function prototype scope. 4084Sema::DeclPtrTy 4085Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4086 const DeclSpec &DS = D.getDeclSpec(); 4087 4088 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4089 VarDecl::StorageClass StorageClass = VarDecl::None; 4090 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4091 StorageClass = VarDecl::Register; 4092 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4093 Diag(DS.getStorageClassSpecLoc(), 4094 diag::err_invalid_storage_class_in_func_decl); 4095 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4096 } 4097 4098 if (D.getDeclSpec().isThreadSpecified()) 4099 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4100 4101 DiagnoseFunctionSpecifiers(D); 4102 4103 // Check that there are no default arguments inside the type of this 4104 // parameter (C++ only). 4105 if (getLangOptions().CPlusPlus) 4106 CheckExtraCXXDefaultArguments(D); 4107 4108 TypeSourceInfo *TInfo = 0; 4109 TagDecl *OwnedDecl = 0; 4110 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4111 4112 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4113 // C++ [dcl.fct]p6: 4114 // Types shall not be defined in return or parameter types. 4115 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4116 << Context.getTypeDeclType(OwnedDecl); 4117 } 4118 4119 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4120 IdentifierInfo *II = D.getIdentifier(); 4121 if (II) { 4122 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4123 ForRedeclaration); 4124 LookupName(R, S); 4125 if (R.isSingleResult()) { 4126 NamedDecl *PrevDecl = R.getFoundDecl(); 4127 if (PrevDecl->isTemplateParameter()) { 4128 // Maybe we will complain about the shadowed template parameter. 4129 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4130 // Just pretend that we didn't see the previous declaration. 4131 PrevDecl = 0; 4132 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4133 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4134 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4135 4136 // Recover by removing the name 4137 II = 0; 4138 D.SetIdentifier(0, D.getIdentifierLoc()); 4139 D.setInvalidType(true); 4140 } 4141 } 4142 } 4143 4144 // Temporarily put parameter variables in the translation unit, not 4145 // the enclosing context. This prevents them from accidentally 4146 // looking like class members in C++. 4147 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4148 TInfo, parmDeclType, II, 4149 D.getIdentifierLoc(), StorageClass); 4150 4151 if (D.isInvalidType()) 4152 New->setInvalidDecl(); 4153 4154 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4155 if (D.getCXXScopeSpec().isSet()) { 4156 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4157 << D.getCXXScopeSpec().getRange(); 4158 New->setInvalidDecl(); 4159 } 4160 4161 // Add the parameter declaration into this scope. 4162 S->AddDecl(DeclPtrTy::make(New)); 4163 if (II) 4164 IdResolver.AddDecl(New); 4165 4166 ProcessDeclAttributes(S, New, D); 4167 4168 if (New->hasAttr<BlocksAttr>()) { 4169 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4170 } 4171 return DeclPtrTy::make(New); 4172} 4173 4174ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4175 TypeSourceInfo *TSInfo, QualType T, 4176 IdentifierInfo *Name, 4177 SourceLocation NameLoc, 4178 VarDecl::StorageClass StorageClass) { 4179 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4180 adjustParameterType(T), TSInfo, 4181 StorageClass, 0); 4182 4183 // Parameters can not be abstract class types. 4184 // For record types, this is done by the AbstractClassUsageDiagnoser once 4185 // the class has been completely parsed. 4186 if (!CurContext->isRecord() && 4187 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4188 AbstractParamType)) 4189 New->setInvalidDecl(); 4190 4191 // Parameter declarators cannot be interface types. All ObjC objects are 4192 // passed by reference. 4193 if (T->isObjCInterfaceType()) { 4194 Diag(NameLoc, 4195 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4196 New->setInvalidDecl(); 4197 } 4198 4199 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4200 // duration shall not be qualified by an address-space qualifier." 4201 // Since all parameters have automatic store duration, they can not have 4202 // an address space. 4203 if (T.getAddressSpace() != 0) { 4204 Diag(NameLoc, diag::err_arg_with_address_space); 4205 New->setInvalidDecl(); 4206 } 4207 4208 return New; 4209} 4210 4211void Sema::ActOnObjCCatchParam(DeclPtrTy D) { 4212 ParmVarDecl *Param = cast<ParmVarDecl>(D.getAs<Decl>()); 4213 Param->setDeclContext(CurContext); 4214} 4215 4216void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4217 SourceLocation LocAfterDecls) { 4218 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4219 "Not a function declarator!"); 4220 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4221 4222 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4223 // for a K&R function. 4224 if (!FTI.hasPrototype) { 4225 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4226 --i; 4227 if (FTI.ArgInfo[i].Param == 0) { 4228 llvm::SmallString<256> Code; 4229 llvm::raw_svector_ostream(Code) << " int " 4230 << FTI.ArgInfo[i].Ident->getName() 4231 << ";\n"; 4232 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4233 << FTI.ArgInfo[i].Ident 4234 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4235 4236 // Implicitly declare the argument as type 'int' for lack of a better 4237 // type. 4238 DeclSpec DS; 4239 const char* PrevSpec; // unused 4240 unsigned DiagID; // unused 4241 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4242 PrevSpec, DiagID); 4243 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4244 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4245 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4246 } 4247 } 4248 } 4249} 4250 4251Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4252 Declarator &D) { 4253 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4254 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4255 "Not a function declarator!"); 4256 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4257 4258 if (FTI.hasPrototype) { 4259 // FIXME: Diagnose arguments without names in C. 4260 } 4261 4262 Scope *ParentScope = FnBodyScope->getParent(); 4263 4264 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4265 MultiTemplateParamsArg(*this), 4266 /*IsFunctionDefinition=*/true); 4267 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4268} 4269 4270static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4271 // Don't warn about invalid declarations. 4272 if (FD->isInvalidDecl()) 4273 return false; 4274 4275 // Or declarations that aren't global. 4276 if (!FD->isGlobal()) 4277 return false; 4278 4279 // Don't warn about C++ member functions. 4280 if (isa<CXXMethodDecl>(FD)) 4281 return false; 4282 4283 // Don't warn about 'main'. 4284 if (FD->isMain()) 4285 return false; 4286 4287 // Don't warn about inline functions. 4288 if (FD->isInlineSpecified()) 4289 return false; 4290 4291 // Don't warn about function templates. 4292 if (FD->getDescribedFunctionTemplate()) 4293 return false; 4294 4295 // Don't warn about function template specializations. 4296 if (FD->isFunctionTemplateSpecialization()) 4297 return false; 4298 4299 bool MissingPrototype = true; 4300 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4301 Prev; Prev = Prev->getPreviousDeclaration()) { 4302 // Ignore any declarations that occur in function or method 4303 // scope, because they aren't visible from the header. 4304 if (Prev->getDeclContext()->isFunctionOrMethod()) 4305 continue; 4306 4307 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4308 break; 4309 } 4310 4311 return MissingPrototype; 4312} 4313 4314Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4315 // Clear the last template instantiation error context. 4316 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4317 4318 if (!D) 4319 return D; 4320 FunctionDecl *FD = 0; 4321 4322 if (FunctionTemplateDecl *FunTmpl 4323 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4324 FD = FunTmpl->getTemplatedDecl(); 4325 else 4326 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4327 4328 // Enter a new function scope 4329 PushFunctionScope(); 4330 4331 // See if this is a redefinition. 4332 // But don't complain if we're in GNU89 mode and the previous definition 4333 // was an extern inline function. 4334 const FunctionDecl *Definition; 4335 if (FD->getBody(Definition) && 4336 !canRedefineFunction(Definition, getLangOptions())) { 4337 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4338 Diag(Definition->getLocation(), diag::note_previous_definition); 4339 } 4340 4341 // Builtin functions cannot be defined. 4342 if (unsigned BuiltinID = FD->getBuiltinID()) { 4343 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4344 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4345 FD->setInvalidDecl(); 4346 } 4347 } 4348 4349 // The return type of a function definition must be complete 4350 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4351 QualType ResultType = FD->getResultType(); 4352 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4353 !FD->isInvalidDecl() && 4354 RequireCompleteType(FD->getLocation(), ResultType, 4355 diag::err_func_def_incomplete_result)) 4356 FD->setInvalidDecl(); 4357 4358 // GNU warning -Wmissing-prototypes: 4359 // Warn if a global function is defined without a previous 4360 // prototype declaration. This warning is issued even if the 4361 // definition itself provides a prototype. The aim is to detect 4362 // global functions that fail to be declared in header files. 4363 if (ShouldWarnAboutMissingPrototype(FD)) 4364 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4365 4366 if (FnBodyScope) 4367 PushDeclContext(FnBodyScope, FD); 4368 4369 // Check the validity of our function parameters 4370 CheckParmsForFunctionDef(FD); 4371 4372 bool ShouldCheckShadow = 4373 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4374 4375 // Introduce our parameters into the function scope 4376 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4377 ParmVarDecl *Param = FD->getParamDecl(p); 4378 Param->setOwningFunction(FD); 4379 4380 // If this has an identifier, add it to the scope stack. 4381 if (Param->getIdentifier() && FnBodyScope) { 4382 if (ShouldCheckShadow) 4383 CheckShadow(FnBodyScope, Param); 4384 4385 PushOnScopeChains(Param, FnBodyScope); 4386 } 4387 } 4388 4389 // Checking attributes of current function definition 4390 // dllimport attribute. 4391 if (FD->getAttr<DLLImportAttr>() && 4392 (!FD->getAttr<DLLExportAttr>())) { 4393 // dllimport attribute cannot be applied to definition. 4394 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4395 Diag(FD->getLocation(), 4396 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4397 << "dllimport"; 4398 FD->setInvalidDecl(); 4399 return DeclPtrTy::make(FD); 4400 } 4401 4402 // Visual C++ appears to not think this is an issue, so only issue 4403 // a warning when Microsoft extensions are disabled. 4404 if (!LangOpts.Microsoft) { 4405 // If a symbol previously declared dllimport is later defined, the 4406 // attribute is ignored in subsequent references, and a warning is 4407 // emitted. 4408 Diag(FD->getLocation(), 4409 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4410 << FD->getNameAsCString() << "dllimport"; 4411 } 4412 } 4413 return DeclPtrTy::make(FD); 4414} 4415 4416Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4417 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4418} 4419 4420Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4421 bool IsInstantiation) { 4422 Decl *dcl = D.getAs<Decl>(); 4423 Stmt *Body = BodyArg.takeAs<Stmt>(); 4424 4425 FunctionDecl *FD = 0; 4426 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4427 if (FunTmpl) 4428 FD = FunTmpl->getTemplatedDecl(); 4429 else 4430 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4431 4432 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4433 4434 if (FD) { 4435 FD->setBody(Body); 4436 if (FD->isMain()) { 4437 // C and C++ allow for main to automagically return 0. 4438 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4439 FD->setHasImplicitReturnZero(true); 4440 WP.disableCheckFallThrough(); 4441 } 4442 4443 if (!FD->isInvalidDecl()) 4444 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4445 4446 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4447 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4448 4449 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4450 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4451 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4452 MD->setBody(Body); 4453 MD->setEndLoc(Body->getLocEnd()); 4454 if (!MD->isInvalidDecl()) 4455 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4456 } else { 4457 Body->Destroy(Context); 4458 return DeclPtrTy(); 4459 } 4460 4461 // Verify and clean out per-function state. 4462 4463 // Check goto/label use. 4464 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4465 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4466 LabelStmt *L = I->second; 4467 4468 // Verify that we have no forward references left. If so, there was a goto 4469 // or address of a label taken, but no definition of it. Label fwd 4470 // definitions are indicated with a null substmt. 4471 if (L->getSubStmt() != 0) 4472 continue; 4473 4474 // Emit error. 4475 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4476 4477 // At this point, we have gotos that use the bogus label. Stitch it into 4478 // the function body so that they aren't leaked and that the AST is well 4479 // formed. 4480 if (Body == 0) { 4481 // The whole function wasn't parsed correctly, just delete this. 4482 L->Destroy(Context); 4483 continue; 4484 } 4485 4486 // Otherwise, the body is valid: we want to stitch the label decl into the 4487 // function somewhere so that it is properly owned and so that the goto 4488 // has a valid target. Do this by creating a new compound stmt with the 4489 // label in it. 4490 4491 // Give the label a sub-statement. 4492 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4493 4494 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4495 cast<CXXTryStmt>(Body)->getTryBlock() : 4496 cast<CompoundStmt>(Body); 4497 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4498 Compound->body_end()); 4499 Elements.push_back(L); 4500 Compound->setStmts(Context, Elements.data(), Elements.size()); 4501 } 4502 4503 if (Body) { 4504 // C++ constructors that have function-try-blocks can't have return 4505 // statements in the handlers of that block. (C++ [except.handle]p14) 4506 // Verify this. 4507 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4508 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4509 4510 // Verify that that gotos and switch cases don't jump into scopes illegally. 4511 // Verify that that gotos and switch cases don't jump into scopes illegally. 4512 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 4513 DiagnoseInvalidJumps(Body); 4514 4515 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4516 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4517 Destructor->getParent()); 4518 4519 // If any errors have occurred, clear out any temporaries that may have 4520 // been leftover. This ensures that these temporaries won't be picked up for 4521 // deletion in some later function. 4522 if (PP.getDiagnostics().hasErrorOccurred()) 4523 ExprTemporaries.clear(); 4524 else if (!isa<FunctionTemplateDecl>(dcl)) { 4525 // Since the body is valid, issue any analysis-based warnings that are 4526 // enabled. 4527 QualType ResultType; 4528 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4529 ResultType = FD->getResultType(); 4530 } 4531 else { 4532 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4533 ResultType = MD->getResultType(); 4534 } 4535 AnalysisWarnings.IssueWarnings(WP, dcl); 4536 } 4537 4538 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4539 } 4540 4541 if (!IsInstantiation) 4542 PopDeclContext(); 4543 4544 PopFunctionOrBlockScope(); 4545 4546 // If any errors have occurred, clear out any temporaries that may have 4547 // been leftover. This ensures that these temporaries won't be picked up for 4548 // deletion in some later function. 4549 if (getDiagnostics().hasErrorOccurred()) 4550 ExprTemporaries.clear(); 4551 4552 return D; 4553} 4554 4555/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4556/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4557NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4558 IdentifierInfo &II, Scope *S) { 4559 // Before we produce a declaration for an implicitly defined 4560 // function, see whether there was a locally-scoped declaration of 4561 // this name as a function or variable. If so, use that 4562 // (non-visible) declaration, and complain about it. 4563 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4564 = LocallyScopedExternalDecls.find(&II); 4565 if (Pos != LocallyScopedExternalDecls.end()) { 4566 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4567 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4568 return Pos->second; 4569 } 4570 4571 // Extension in C99. Legal in C90, but warn about it. 4572 if (II.getName().startswith("__builtin_")) 4573 Diag(Loc, diag::warn_builtin_unknown) << &II; 4574 else if (getLangOptions().C99) 4575 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4576 else 4577 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4578 4579 // Set a Declarator for the implicit definition: int foo(); 4580 const char *Dummy; 4581 DeclSpec DS; 4582 unsigned DiagID; 4583 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4584 Error = Error; // Silence warning. 4585 assert(!Error && "Error setting up implicit decl!"); 4586 Declarator D(DS, Declarator::BlockContext); 4587 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4588 0, 0, false, SourceLocation(), 4589 false, 0,0,0, Loc, Loc, D), 4590 SourceLocation()); 4591 D.SetIdentifier(&II, Loc); 4592 4593 // Insert this function into translation-unit scope. 4594 4595 DeclContext *PrevDC = CurContext; 4596 CurContext = Context.getTranslationUnitDecl(); 4597 4598 FunctionDecl *FD = 4599 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4600 FD->setImplicit(); 4601 4602 CurContext = PrevDC; 4603 4604 AddKnownFunctionAttributes(FD); 4605 4606 return FD; 4607} 4608 4609/// \brief Adds any function attributes that we know a priori based on 4610/// the declaration of this function. 4611/// 4612/// These attributes can apply both to implicitly-declared builtins 4613/// (like __builtin___printf_chk) or to library-declared functions 4614/// like NSLog or printf. 4615void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4616 if (FD->isInvalidDecl()) 4617 return; 4618 4619 // If this is a built-in function, map its builtin attributes to 4620 // actual attributes. 4621 if (unsigned BuiltinID = FD->getBuiltinID()) { 4622 // Handle printf-formatting attributes. 4623 unsigned FormatIdx; 4624 bool HasVAListArg; 4625 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4626 if (!FD->getAttr<FormatAttr>()) 4627 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4628 HasVAListArg ? 0 : FormatIdx+2)); 4629 } 4630 4631 // Mark const if we don't care about errno and that is the only 4632 // thing preventing the function from being const. This allows 4633 // IRgen to use LLVM intrinsics for such functions. 4634 if (!getLangOptions().MathErrno && 4635 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4636 if (!FD->getAttr<ConstAttr>()) 4637 FD->addAttr(::new (Context) ConstAttr()); 4638 } 4639 4640 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4641 FD->setType(Context.getNoReturnType(FD->getType())); 4642 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4643 FD->addAttr(::new (Context) NoThrowAttr()); 4644 if (Context.BuiltinInfo.isConst(BuiltinID)) 4645 FD->addAttr(::new (Context) ConstAttr()); 4646 } 4647 4648 IdentifierInfo *Name = FD->getIdentifier(); 4649 if (!Name) 4650 return; 4651 if ((!getLangOptions().CPlusPlus && 4652 FD->getDeclContext()->isTranslationUnit()) || 4653 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4654 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4655 LinkageSpecDecl::lang_c)) { 4656 // Okay: this could be a libc/libm/Objective-C function we know 4657 // about. 4658 } else 4659 return; 4660 4661 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4662 // FIXME: NSLog and NSLogv should be target specific 4663 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4664 // FIXME: We known better than our headers. 4665 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4666 } else 4667 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4668 Name->isStr("NSLogv") ? 0 : 2)); 4669 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4670 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4671 // target-specific builtins, perhaps? 4672 if (!FD->getAttr<FormatAttr>()) 4673 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4674 Name->isStr("vasprintf") ? 0 : 3)); 4675 } 4676} 4677 4678TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4679 TypeSourceInfo *TInfo) { 4680 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4681 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4682 4683 if (!TInfo) { 4684 assert(D.isInvalidType() && "no declarator info for valid type"); 4685 TInfo = Context.getTrivialTypeSourceInfo(T); 4686 } 4687 4688 // Scope manipulation handled by caller. 4689 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4690 D.getIdentifierLoc(), 4691 D.getIdentifier(), 4692 TInfo); 4693 4694 if (const TagType *TT = T->getAs<TagType>()) { 4695 TagDecl *TD = TT->getDecl(); 4696 4697 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4698 // keep track of the TypedefDecl. 4699 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4700 TD->setTypedefForAnonDecl(NewTD); 4701 } 4702 4703 if (D.isInvalidType()) 4704 NewTD->setInvalidDecl(); 4705 return NewTD; 4706} 4707 4708 4709/// \brief Determine whether a tag with a given kind is acceptable 4710/// as a redeclaration of the given tag declaration. 4711/// 4712/// \returns true if the new tag kind is acceptable, false otherwise. 4713bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4714 TagDecl::TagKind NewTag, 4715 SourceLocation NewTagLoc, 4716 const IdentifierInfo &Name) { 4717 // C++ [dcl.type.elab]p3: 4718 // The class-key or enum keyword present in the 4719 // elaborated-type-specifier shall agree in kind with the 4720 // declaration to which the name in theelaborated-type-specifier 4721 // refers. This rule also applies to the form of 4722 // elaborated-type-specifier that declares a class-name or 4723 // friend class since it can be construed as referring to the 4724 // definition of the class. Thus, in any 4725 // elaborated-type-specifier, the enum keyword shall be used to 4726 // refer to an enumeration (7.2), the union class-keyshall be 4727 // used to refer to a union (clause 9), and either the class or 4728 // struct class-key shall be used to refer to a class (clause 9) 4729 // declared using the class or struct class-key. 4730 TagDecl::TagKind OldTag = Previous->getTagKind(); 4731 if (OldTag == NewTag) 4732 return true; 4733 4734 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4735 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4736 // Warn about the struct/class tag mismatch. 4737 bool isTemplate = false; 4738 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4739 isTemplate = Record->getDescribedClassTemplate(); 4740 4741 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4742 << (NewTag == TagDecl::TK_class) 4743 << isTemplate << &Name 4744 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 4745 OldTag == TagDecl::TK_class? "class" : "struct"); 4746 Diag(Previous->getLocation(), diag::note_previous_use); 4747 return true; 4748 } 4749 return false; 4750} 4751 4752/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4753/// former case, Name will be non-null. In the later case, Name will be null. 4754/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4755/// reference/declaration/definition of a tag. 4756Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4757 SourceLocation KWLoc, CXXScopeSpec &SS, 4758 IdentifierInfo *Name, SourceLocation NameLoc, 4759 AttributeList *Attr, AccessSpecifier AS, 4760 MultiTemplateParamsArg TemplateParameterLists, 4761 bool &OwnedDecl, bool &IsDependent) { 4762 // If this is not a definition, it must have a name. 4763 assert((Name != 0 || TUK == TUK_Definition) && 4764 "Nameless record must be a definition!"); 4765 4766 OwnedDecl = false; 4767 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4768 4769 // FIXME: Check explicit specializations more carefully. 4770 bool isExplicitSpecialization = false; 4771 if (TUK != TUK_Reference) { 4772 if (TemplateParameterList *TemplateParams 4773 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4774 (TemplateParameterList**)TemplateParameterLists.get(), 4775 TemplateParameterLists.size(), 4776 TUK == TUK_Friend, 4777 isExplicitSpecialization)) { 4778 if (TemplateParams->size() > 0) { 4779 // This is a declaration or definition of a class template (which may 4780 // be a member of another template). 4781 OwnedDecl = false; 4782 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4783 SS, Name, NameLoc, Attr, 4784 TemplateParams, 4785 AS); 4786 TemplateParameterLists.release(); 4787 return Result.get(); 4788 } else { 4789 // The "template<>" header is extraneous. 4790 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4791 << ElaboratedType::getNameForTagKind(Kind) << Name; 4792 isExplicitSpecialization = true; 4793 } 4794 } 4795 4796 TemplateParameterLists.release(); 4797 } 4798 4799 DeclContext *SearchDC = CurContext; 4800 DeclContext *DC = CurContext; 4801 bool isStdBadAlloc = false; 4802 bool Invalid = false; 4803 4804 RedeclarationKind Redecl = ForRedeclaration; 4805 if (TUK == TUK_Friend || TUK == TUK_Reference) 4806 Redecl = NotForRedeclaration; 4807 4808 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4809 4810 if (Name && SS.isNotEmpty()) { 4811 // We have a nested-name tag ('struct foo::bar'). 4812 4813 // Check for invalid 'foo::'. 4814 if (SS.isInvalid()) { 4815 Name = 0; 4816 goto CreateNewDecl; 4817 } 4818 4819 // If this is a friend or a reference to a class in a dependent 4820 // context, don't try to make a decl for it. 4821 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4822 DC = computeDeclContext(SS, false); 4823 if (!DC) { 4824 IsDependent = true; 4825 return DeclPtrTy(); 4826 } 4827 } 4828 4829 if (RequireCompleteDeclContext(SS)) 4830 return DeclPtrTy::make((Decl *)0); 4831 4832 DC = computeDeclContext(SS, true); 4833 SearchDC = DC; 4834 // Look-up name inside 'foo::'. 4835 LookupQualifiedName(Previous, DC); 4836 4837 if (Previous.isAmbiguous()) 4838 return DeclPtrTy(); 4839 4840 if (Previous.empty()) { 4841 // Name lookup did not find anything. However, if the 4842 // nested-name-specifier refers to the current instantiation, 4843 // and that current instantiation has any dependent base 4844 // classes, we might find something at instantiation time: treat 4845 // this as a dependent elaborated-type-specifier. 4846 if (Previous.wasNotFoundInCurrentInstantiation()) { 4847 IsDependent = true; 4848 return DeclPtrTy(); 4849 } 4850 4851 // A tag 'foo::bar' must already exist. 4852 Diag(NameLoc, diag::err_not_tag_in_scope) 4853 << Kind << Name << DC << SS.getRange(); 4854 Name = 0; 4855 Invalid = true; 4856 goto CreateNewDecl; 4857 } 4858 } else if (Name) { 4859 // If this is a named struct, check to see if there was a previous forward 4860 // declaration or definition. 4861 // FIXME: We're looking into outer scopes here, even when we 4862 // shouldn't be. Doing so can result in ambiguities that we 4863 // shouldn't be diagnosing. 4864 LookupName(Previous, S); 4865 4866 // Note: there used to be some attempt at recovery here. 4867 if (Previous.isAmbiguous()) 4868 return DeclPtrTy(); 4869 4870 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4871 // FIXME: This makes sure that we ignore the contexts associated 4872 // with C structs, unions, and enums when looking for a matching 4873 // tag declaration or definition. See the similar lookup tweak 4874 // in Sema::LookupName; is there a better way to deal with this? 4875 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4876 SearchDC = SearchDC->getParent(); 4877 } 4878 } 4879 4880 if (Previous.isSingleResult() && 4881 Previous.getFoundDecl()->isTemplateParameter()) { 4882 // Maybe we will complain about the shadowed template parameter. 4883 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4884 // Just pretend that we didn't see the previous declaration. 4885 Previous.clear(); 4886 } 4887 4888 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4889 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4890 // This is a declaration of or a reference to "std::bad_alloc". 4891 isStdBadAlloc = true; 4892 4893 if (Previous.empty() && StdBadAlloc) { 4894 // std::bad_alloc has been implicitly declared (but made invisible to 4895 // name lookup). Fill in this implicit declaration as the previous 4896 // declaration, so that the declarations get chained appropriately. 4897 Previous.addDecl(StdBadAlloc); 4898 } 4899 } 4900 4901 // If we didn't find a previous declaration, and this is a reference 4902 // (or friend reference), move to the correct scope. In C++, we 4903 // also need to do a redeclaration lookup there, just in case 4904 // there's a shadow friend decl. 4905 if (Name && Previous.empty() && 4906 (TUK == TUK_Reference || TUK == TUK_Friend)) { 4907 if (Invalid) goto CreateNewDecl; 4908 assert(SS.isEmpty()); 4909 4910 if (TUK == TUK_Reference) { 4911 // C++ [basic.scope.pdecl]p5: 4912 // -- for an elaborated-type-specifier of the form 4913 // 4914 // class-key identifier 4915 // 4916 // if the elaborated-type-specifier is used in the 4917 // decl-specifier-seq or parameter-declaration-clause of a 4918 // function defined in namespace scope, the identifier is 4919 // declared as a class-name in the namespace that contains 4920 // the declaration; otherwise, except as a friend 4921 // declaration, the identifier is declared in the smallest 4922 // non-class, non-function-prototype scope that contains the 4923 // declaration. 4924 // 4925 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4926 // C structs and unions. 4927 // 4928 // It is an error in C++ to declare (rather than define) an enum 4929 // type, including via an elaborated type specifier. We'll 4930 // diagnose that later; for now, declare the enum in the same 4931 // scope as we would have picked for any other tag type. 4932 // 4933 // GNU C also supports this behavior as part of its incomplete 4934 // enum types extension, while GNU C++ does not. 4935 // 4936 // Find the context where we'll be declaring the tag. 4937 // FIXME: We would like to maintain the current DeclContext as the 4938 // lexical context, 4939 while (SearchDC->isRecord()) 4940 SearchDC = SearchDC->getParent(); 4941 4942 // Find the scope where we'll be declaring the tag. 4943 while (S->isClassScope() || 4944 (getLangOptions().CPlusPlus && 4945 S->isFunctionPrototypeScope()) || 4946 ((S->getFlags() & Scope::DeclScope) == 0) || 4947 (S->getEntity() && 4948 ((DeclContext *)S->getEntity())->isTransparentContext())) 4949 S = S->getParent(); 4950 } else { 4951 assert(TUK == TUK_Friend); 4952 // C++ [namespace.memdef]p3: 4953 // If a friend declaration in a non-local class first declares a 4954 // class or function, the friend class or function is a member of 4955 // the innermost enclosing namespace. 4956 SearchDC = SearchDC->getEnclosingNamespaceContext(); 4957 } 4958 4959 // In C++, look for a shadow friend decl. 4960 if (getLangOptions().CPlusPlus) { 4961 Previous.setRedeclarationKind(ForRedeclaration); 4962 LookupQualifiedName(Previous, SearchDC); 4963 } 4964 } 4965 4966 if (!Previous.empty()) { 4967 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 4968 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4969 // If this is a use of a previous tag, or if the tag is already declared 4970 // in the same scope (so that the definition/declaration completes or 4971 // rementions the tag), reuse the decl. 4972 if (TUK == TUK_Reference || TUK == TUK_Friend || 4973 isDeclInScope(PrevDecl, SearchDC, S)) { 4974 // Make sure that this wasn't declared as an enum and now used as a 4975 // struct or something similar. 4976 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4977 bool SafeToContinue 4978 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4979 Kind != TagDecl::TK_enum); 4980 if (SafeToContinue) 4981 Diag(KWLoc, diag::err_use_with_wrong_tag) 4982 << Name 4983 << FixItHint::CreateReplacement(SourceRange(KWLoc), 4984 PrevTagDecl->getKindName()); 4985 else 4986 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4987 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4988 4989 if (SafeToContinue) 4990 Kind = PrevTagDecl->getTagKind(); 4991 else { 4992 // Recover by making this an anonymous redefinition. 4993 Name = 0; 4994 Previous.clear(); 4995 Invalid = true; 4996 } 4997 } 4998 4999 if (!Invalid) { 5000 // If this is a use, just return the declaration we found. 5001 5002 // FIXME: In the future, return a variant or some other clue 5003 // for the consumer of this Decl to know it doesn't own it. 5004 // For our current ASTs this shouldn't be a problem, but will 5005 // need to be changed with DeclGroups. 5006 if (TUK == TUK_Reference || TUK == TUK_Friend) 5007 return DeclPtrTy::make(PrevTagDecl); 5008 5009 // Diagnose attempts to redefine a tag. 5010 if (TUK == TUK_Definition) { 5011 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5012 // If we're defining a specialization and the previous definition 5013 // is from an implicit instantiation, don't emit an error 5014 // here; we'll catch this in the general case below. 5015 if (!isExplicitSpecialization || 5016 !isa<CXXRecordDecl>(Def) || 5017 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5018 == TSK_ExplicitSpecialization) { 5019 Diag(NameLoc, diag::err_redefinition) << Name; 5020 Diag(Def->getLocation(), diag::note_previous_definition); 5021 // If this is a redefinition, recover by making this 5022 // struct be anonymous, which will make any later 5023 // references get the previous definition. 5024 Name = 0; 5025 Previous.clear(); 5026 Invalid = true; 5027 } 5028 } else { 5029 // If the type is currently being defined, complain 5030 // about a nested redefinition. 5031 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5032 if (Tag->isBeingDefined()) { 5033 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5034 Diag(PrevTagDecl->getLocation(), 5035 diag::note_previous_definition); 5036 Name = 0; 5037 Previous.clear(); 5038 Invalid = true; 5039 } 5040 } 5041 5042 // Okay, this is definition of a previously declared or referenced 5043 // tag PrevDecl. We're going to create a new Decl for it. 5044 } 5045 } 5046 // If we get here we have (another) forward declaration or we 5047 // have a definition. Just create a new decl. 5048 5049 } else { 5050 // If we get here, this is a definition of a new tag type in a nested 5051 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5052 // new decl/type. We set PrevDecl to NULL so that the entities 5053 // have distinct types. 5054 Previous.clear(); 5055 } 5056 // If we get here, we're going to create a new Decl. If PrevDecl 5057 // is non-NULL, it's a definition of the tag declared by 5058 // PrevDecl. If it's NULL, we have a new definition. 5059 } else { 5060 // PrevDecl is a namespace, template, or anything else 5061 // that lives in the IDNS_Tag identifier namespace. 5062 if (TUK == TUK_Reference || TUK == TUK_Friend || 5063 isDeclInScope(PrevDecl, SearchDC, S)) { 5064 // The tag name clashes with a namespace name, issue an error and 5065 // recover by making this tag be anonymous. 5066 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5067 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5068 Name = 0; 5069 Previous.clear(); 5070 Invalid = true; 5071 } else { 5072 // The existing declaration isn't relevant to us; we're in a 5073 // new scope, so clear out the previous declaration. 5074 Previous.clear(); 5075 } 5076 } 5077 } 5078 5079CreateNewDecl: 5080 5081 TagDecl *PrevDecl = 0; 5082 if (Previous.isSingleResult()) 5083 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5084 5085 // If there is an identifier, use the location of the identifier as the 5086 // location of the decl, otherwise use the location of the struct/union 5087 // keyword. 5088 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5089 5090 // Otherwise, create a new declaration. If there is a previous 5091 // declaration of the same entity, the two will be linked via 5092 // PrevDecl. 5093 TagDecl *New; 5094 5095 if (Kind == TagDecl::TK_enum) { 5096 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5097 // enum X { A, B, C } D; D should chain to X. 5098 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5099 cast_or_null<EnumDecl>(PrevDecl)); 5100 // If this is an undefined enum, warn. 5101 if (TUK != TUK_Definition && !Invalid) { 5102 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5103 : diag::ext_forward_ref_enum; 5104 Diag(Loc, DK); 5105 } 5106 } else { 5107 // struct/union/class 5108 5109 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5110 // struct X { int A; } D; D should chain to X. 5111 if (getLangOptions().CPlusPlus) { 5112 // FIXME: Look for a way to use RecordDecl for simple structs. 5113 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5114 cast_or_null<CXXRecordDecl>(PrevDecl)); 5115 5116 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5117 StdBadAlloc = cast<CXXRecordDecl>(New); 5118 } else 5119 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5120 cast_or_null<RecordDecl>(PrevDecl)); 5121 } 5122 5123 // Maybe add qualifier info. 5124 if (SS.isNotEmpty()) { 5125 NestedNameSpecifier *NNS 5126 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5127 New->setQualifierInfo(NNS, SS.getRange()); 5128 } 5129 5130 if (Kind != TagDecl::TK_enum) { 5131 // Handle #pragma pack: if the #pragma pack stack has non-default 5132 // alignment, make up a packed attribute for this decl. These 5133 // attributes are checked when the ASTContext lays out the 5134 // structure. 5135 // 5136 // It is important for implementing the correct semantics that this 5137 // happen here (in act on tag decl). The #pragma pack stack is 5138 // maintained as a result of parser callbacks which can occur at 5139 // many points during the parsing of a struct declaration (because 5140 // the #pragma tokens are effectively skipped over during the 5141 // parsing of the struct). 5142 if (unsigned Alignment = getPragmaPackAlignment()) 5143 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5144 } 5145 5146 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5147 // C++ [dcl.typedef]p3: 5148 // [...] Similarly, in a given scope, a class or enumeration 5149 // shall not be declared with the same name as a typedef-name 5150 // that is declared in that scope and refers to a type other 5151 // than the class or enumeration itself. 5152 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5153 ForRedeclaration); 5154 LookupName(Lookup, S); 5155 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5156 NamedDecl *PrevTypedefNamed = PrevTypedef; 5157 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5158 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5159 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5160 Diag(Loc, diag::err_tag_definition_of_typedef) 5161 << Context.getTypeDeclType(New) 5162 << PrevTypedef->getUnderlyingType(); 5163 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5164 Invalid = true; 5165 } 5166 } 5167 5168 // If this is a specialization of a member class (of a class template), 5169 // check the specialization. 5170 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5171 Invalid = true; 5172 5173 if (Invalid) 5174 New->setInvalidDecl(); 5175 5176 if (Attr) 5177 ProcessDeclAttributeList(S, New, Attr); 5178 5179 // If we're declaring or defining a tag in function prototype scope 5180 // in C, note that this type can only be used within the function. 5181 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5182 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5183 5184 // Set the lexical context. If the tag has a C++ scope specifier, the 5185 // lexical context will be different from the semantic context. 5186 New->setLexicalDeclContext(CurContext); 5187 5188 // Mark this as a friend decl if applicable. 5189 if (TUK == TUK_Friend) 5190 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5191 5192 // Set the access specifier. 5193 if (!Invalid && SearchDC->isRecord()) 5194 SetMemberAccessSpecifier(New, PrevDecl, AS); 5195 5196 if (TUK == TUK_Definition) 5197 New->startDefinition(); 5198 5199 // If this has an identifier, add it to the scope stack. 5200 if (TUK == TUK_Friend) { 5201 // We might be replacing an existing declaration in the lookup tables; 5202 // if so, borrow its access specifier. 5203 if (PrevDecl) 5204 New->setAccess(PrevDecl->getAccess()); 5205 5206 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5207 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5208 if (Name) // can be null along some error paths 5209 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5210 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5211 } else if (Name) { 5212 S = getNonFieldDeclScope(S); 5213 PushOnScopeChains(New, S); 5214 } else { 5215 CurContext->addDecl(New); 5216 } 5217 5218 // If this is the C FILE type, notify the AST context. 5219 if (IdentifierInfo *II = New->getIdentifier()) 5220 if (!New->isInvalidDecl() && 5221 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5222 II->isStr("FILE")) 5223 Context.setFILEDecl(New); 5224 5225 OwnedDecl = true; 5226 return DeclPtrTy::make(New); 5227} 5228 5229void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5230 AdjustDeclIfTemplate(TagD); 5231 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5232 5233 // Enter the tag context. 5234 PushDeclContext(S, Tag); 5235} 5236 5237void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5238 SourceLocation LBraceLoc) { 5239 AdjustDeclIfTemplate(TagD); 5240 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5241 5242 FieldCollector->StartClass(); 5243 5244 if (!Record->getIdentifier()) 5245 return; 5246 5247 // C++ [class]p2: 5248 // [...] The class-name is also inserted into the scope of the 5249 // class itself; this is known as the injected-class-name. For 5250 // purposes of access checking, the injected-class-name is treated 5251 // as if it were a public member name. 5252 CXXRecordDecl *InjectedClassName 5253 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5254 CurContext, Record->getLocation(), 5255 Record->getIdentifier(), 5256 Record->getTagKeywordLoc(), 5257 Record); 5258 InjectedClassName->setImplicit(); 5259 InjectedClassName->setAccess(AS_public); 5260 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5261 InjectedClassName->setDescribedClassTemplate(Template); 5262 PushOnScopeChains(InjectedClassName, S); 5263 assert(InjectedClassName->isInjectedClassName() && 5264 "Broken injected-class-name"); 5265} 5266 5267// Traverses the class and any nested classes, making a note of any 5268// dynamic classes that have no key function so that we can mark all of 5269// their virtual member functions as "used" at the end of the translation 5270// unit. This ensures that all functions needed by the vtable will get 5271// instantiated/synthesized. 5272static void 5273RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5274 SourceLocation Loc) { 5275 // We don't look at dependent or undefined classes. 5276 if (Record->isDependentContext() || !Record->isDefinition()) 5277 return; 5278 5279 if (Record->isDynamicClass()) { 5280 const CXXMethodDecl *KeyFunction = S.Context.getKeyFunction(Record); 5281 5282 if (!KeyFunction) 5283 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, 5284 Loc)); 5285 5286 if ((!KeyFunction || (KeyFunction->getBody() && KeyFunction->isInlined())) 5287 && Record->getLinkage() == ExternalLinkage) 5288 S.Diag(Record->getLocation(), diag::warn_weak_vtable) << Record; 5289 } 5290 for (DeclContext::decl_iterator D = Record->decls_begin(), 5291 DEnd = Record->decls_end(); 5292 D != DEnd; ++D) { 5293 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5294 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5295 } 5296} 5297 5298void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5299 SourceLocation RBraceLoc) { 5300 AdjustDeclIfTemplate(TagD); 5301 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5302 Tag->setRBraceLoc(RBraceLoc); 5303 5304 if (isa<CXXRecordDecl>(Tag)) 5305 FieldCollector->FinishClass(); 5306 5307 // Exit this scope of this tag's definition. 5308 PopDeclContext(); 5309 5310 if (isa<CXXRecordDecl>(Tag) && !Tag->getLexicalDeclContext()->isRecord()) 5311 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5312 RBraceLoc); 5313 5314 // Notify the consumer that we've defined a tag. 5315 Consumer.HandleTagDeclDefinition(Tag); 5316} 5317 5318void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5319 AdjustDeclIfTemplate(TagD); 5320 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5321 Tag->setInvalidDecl(); 5322 5323 // We're undoing ActOnTagStartDefinition here, not 5324 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5325 // the FieldCollector. 5326 5327 PopDeclContext(); 5328} 5329 5330// Note that FieldName may be null for anonymous bitfields. 5331bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5332 QualType FieldTy, const Expr *BitWidth, 5333 bool *ZeroWidth) { 5334 // Default to true; that shouldn't confuse checks for emptiness 5335 if (ZeroWidth) 5336 *ZeroWidth = true; 5337 5338 // C99 6.7.2.1p4 - verify the field type. 5339 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5340 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5341 // Handle incomplete types with specific error. 5342 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5343 return true; 5344 if (FieldName) 5345 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5346 << FieldName << FieldTy << BitWidth->getSourceRange(); 5347 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5348 << FieldTy << BitWidth->getSourceRange(); 5349 } 5350 5351 // If the bit-width is type- or value-dependent, don't try to check 5352 // it now. 5353 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5354 return false; 5355 5356 llvm::APSInt Value; 5357 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5358 return true; 5359 5360 if (Value != 0 && ZeroWidth) 5361 *ZeroWidth = false; 5362 5363 // Zero-width bitfield is ok for anonymous field. 5364 if (Value == 0 && FieldName) 5365 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5366 5367 if (Value.isSigned() && Value.isNegative()) { 5368 if (FieldName) 5369 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5370 << FieldName << Value.toString(10); 5371 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5372 << Value.toString(10); 5373 } 5374 5375 if (!FieldTy->isDependentType()) { 5376 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5377 if (Value.getZExtValue() > TypeSize) { 5378 if (FieldName) 5379 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5380 << FieldName << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5381 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5382 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5383 } 5384 } 5385 5386 return false; 5387} 5388 5389/// ActOnField - Each field of a struct/union/class is passed into this in order 5390/// to create a FieldDecl object for it. 5391Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5392 SourceLocation DeclStart, 5393 Declarator &D, ExprTy *BitfieldWidth) { 5394 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5395 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5396 AS_public); 5397 return DeclPtrTy::make(Res); 5398} 5399 5400/// HandleField - Analyze a field of a C struct or a C++ data member. 5401/// 5402FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5403 SourceLocation DeclStart, 5404 Declarator &D, Expr *BitWidth, 5405 AccessSpecifier AS) { 5406 IdentifierInfo *II = D.getIdentifier(); 5407 SourceLocation Loc = DeclStart; 5408 if (II) Loc = D.getIdentifierLoc(); 5409 5410 TypeSourceInfo *TInfo = 0; 5411 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5412 if (getLangOptions().CPlusPlus) 5413 CheckExtraCXXDefaultArguments(D); 5414 5415 DiagnoseFunctionSpecifiers(D); 5416 5417 if (D.getDeclSpec().isThreadSpecified()) 5418 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5419 5420 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5421 ForRedeclaration); 5422 5423 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5424 // Maybe we will complain about the shadowed template parameter. 5425 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5426 // Just pretend that we didn't see the previous declaration. 5427 PrevDecl = 0; 5428 } 5429 5430 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5431 PrevDecl = 0; 5432 5433 bool Mutable 5434 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5435 SourceLocation TSSL = D.getSourceRange().getBegin(); 5436 FieldDecl *NewFD 5437 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5438 AS, PrevDecl, &D); 5439 5440 if (NewFD->isInvalidDecl()) 5441 Record->setInvalidDecl(); 5442 5443 if (NewFD->isInvalidDecl() && PrevDecl) { 5444 // Don't introduce NewFD into scope; there's already something 5445 // with the same name in the same scope. 5446 } else if (II) { 5447 PushOnScopeChains(NewFD, S); 5448 } else 5449 Record->addDecl(NewFD); 5450 5451 return NewFD; 5452} 5453 5454/// \brief Build a new FieldDecl and check its well-formedness. 5455/// 5456/// This routine builds a new FieldDecl given the fields name, type, 5457/// record, etc. \p PrevDecl should refer to any previous declaration 5458/// with the same name and in the same scope as the field to be 5459/// created. 5460/// 5461/// \returns a new FieldDecl. 5462/// 5463/// \todo The Declarator argument is a hack. It will be removed once 5464FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5465 TypeSourceInfo *TInfo, 5466 RecordDecl *Record, SourceLocation Loc, 5467 bool Mutable, Expr *BitWidth, 5468 SourceLocation TSSL, 5469 AccessSpecifier AS, NamedDecl *PrevDecl, 5470 Declarator *D) { 5471 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5472 bool InvalidDecl = false; 5473 if (D) InvalidDecl = D->isInvalidType(); 5474 5475 // If we receive a broken type, recover by assuming 'int' and 5476 // marking this declaration as invalid. 5477 if (T.isNull()) { 5478 InvalidDecl = true; 5479 T = Context.IntTy; 5480 } 5481 5482 QualType EltTy = Context.getBaseElementType(T); 5483 if (!EltTy->isDependentType() && 5484 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5485 InvalidDecl = true; 5486 5487 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5488 // than a variably modified type. 5489 if (!InvalidDecl && T->isVariablyModifiedType()) { 5490 bool SizeIsNegative; 5491 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5492 SizeIsNegative); 5493 if (!FixedTy.isNull()) { 5494 Diag(Loc, diag::warn_illegal_constant_array_size); 5495 T = FixedTy; 5496 } else { 5497 if (SizeIsNegative) 5498 Diag(Loc, diag::err_typecheck_negative_array_size); 5499 else 5500 Diag(Loc, diag::err_typecheck_field_variable_size); 5501 InvalidDecl = true; 5502 } 5503 } 5504 5505 // Fields can not have abstract class types 5506 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5507 diag::err_abstract_type_in_decl, 5508 AbstractFieldType)) 5509 InvalidDecl = true; 5510 5511 bool ZeroWidth = false; 5512 // If this is declared as a bit-field, check the bit-field. 5513 if (!InvalidDecl && BitWidth && 5514 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5515 InvalidDecl = true; 5516 DeleteExpr(BitWidth); 5517 BitWidth = 0; 5518 ZeroWidth = false; 5519 } 5520 5521 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5522 BitWidth, Mutable); 5523 if (InvalidDecl) 5524 NewFD->setInvalidDecl(); 5525 5526 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5527 Diag(Loc, diag::err_duplicate_member) << II; 5528 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5529 NewFD->setInvalidDecl(); 5530 } 5531 5532 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5533 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5534 5535 if (!T->isPODType()) 5536 CXXRecord->setPOD(false); 5537 if (!ZeroWidth) 5538 CXXRecord->setEmpty(false); 5539 5540 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5541 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5542 5543 if (!RDecl->hasTrivialConstructor()) 5544 CXXRecord->setHasTrivialConstructor(false); 5545 if (!RDecl->hasTrivialCopyConstructor()) 5546 CXXRecord->setHasTrivialCopyConstructor(false); 5547 if (!RDecl->hasTrivialCopyAssignment()) 5548 CXXRecord->setHasTrivialCopyAssignment(false); 5549 if (!RDecl->hasTrivialDestructor()) 5550 CXXRecord->setHasTrivialDestructor(false); 5551 5552 // C++ 9.5p1: An object of a class with a non-trivial 5553 // constructor, a non-trivial copy constructor, a non-trivial 5554 // destructor, or a non-trivial copy assignment operator 5555 // cannot be a member of a union, nor can an array of such 5556 // objects. 5557 // TODO: C++0x alters this restriction significantly. 5558 if (Record->isUnion()) { 5559 // We check for copy constructors before constructors 5560 // because otherwise we'll never get complaints about 5561 // copy constructors. 5562 5563 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5564 5565 CXXSpecialMember member; 5566 if (!RDecl->hasTrivialCopyConstructor()) 5567 member = CXXCopyConstructor; 5568 else if (!RDecl->hasTrivialConstructor()) 5569 member = CXXDefaultConstructor; 5570 else if (!RDecl->hasTrivialCopyAssignment()) 5571 member = CXXCopyAssignment; 5572 else if (!RDecl->hasTrivialDestructor()) 5573 member = CXXDestructor; 5574 else 5575 member = invalid; 5576 5577 if (member != invalid) { 5578 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5579 DiagnoseNontrivial(RT, member); 5580 NewFD->setInvalidDecl(); 5581 } 5582 } 5583 } 5584 } 5585 5586 // FIXME: We need to pass in the attributes given an AST 5587 // representation, not a parser representation. 5588 if (D) 5589 // FIXME: What to pass instead of TUScope? 5590 ProcessDeclAttributes(TUScope, NewFD, *D); 5591 5592 if (T.isObjCGCWeak()) 5593 Diag(Loc, diag::warn_attribute_weak_on_field); 5594 5595 NewFD->setAccess(AS); 5596 5597 // C++ [dcl.init.aggr]p1: 5598 // An aggregate is an array or a class (clause 9) with [...] no 5599 // private or protected non-static data members (clause 11). 5600 // A POD must be an aggregate. 5601 if (getLangOptions().CPlusPlus && 5602 (AS == AS_private || AS == AS_protected)) { 5603 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5604 CXXRecord->setAggregate(false); 5605 CXXRecord->setPOD(false); 5606 } 5607 5608 return NewFD; 5609} 5610 5611/// DiagnoseNontrivial - Given that a class has a non-trivial 5612/// special member, figure out why. 5613void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5614 QualType QT(T, 0U); 5615 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5616 5617 // Check whether the member was user-declared. 5618 switch (member) { 5619 case CXXDefaultConstructor: 5620 if (RD->hasUserDeclaredConstructor()) { 5621 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5622 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5623 const FunctionDecl *body = 0; 5624 ci->getBody(body); 5625 if (!body || 5626 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5627 SourceLocation CtorLoc = ci->getLocation(); 5628 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5629 return; 5630 } 5631 } 5632 5633 assert(0 && "found no user-declared constructors"); 5634 return; 5635 } 5636 break; 5637 5638 case CXXCopyConstructor: 5639 if (RD->hasUserDeclaredCopyConstructor()) { 5640 SourceLocation CtorLoc = 5641 RD->getCopyConstructor(Context, 0)->getLocation(); 5642 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5643 return; 5644 } 5645 break; 5646 5647 case CXXCopyAssignment: 5648 if (RD->hasUserDeclaredCopyAssignment()) { 5649 // FIXME: this should use the location of the copy 5650 // assignment, not the type. 5651 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5652 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5653 return; 5654 } 5655 break; 5656 5657 case CXXDestructor: 5658 if (RD->hasUserDeclaredDestructor()) { 5659 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5660 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5661 return; 5662 } 5663 break; 5664 } 5665 5666 typedef CXXRecordDecl::base_class_iterator base_iter; 5667 5668 // Virtual bases and members inhibit trivial copying/construction, 5669 // but not trivial destruction. 5670 if (member != CXXDestructor) { 5671 // Check for virtual bases. vbases includes indirect virtual bases, 5672 // so we just iterate through the direct bases. 5673 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5674 if (bi->isVirtual()) { 5675 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5676 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5677 return; 5678 } 5679 5680 // Check for virtual methods. 5681 typedef CXXRecordDecl::method_iterator meth_iter; 5682 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5683 ++mi) { 5684 if (mi->isVirtual()) { 5685 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5686 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5687 return; 5688 } 5689 } 5690 } 5691 5692 bool (CXXRecordDecl::*hasTrivial)() const; 5693 switch (member) { 5694 case CXXDefaultConstructor: 5695 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5696 case CXXCopyConstructor: 5697 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5698 case CXXCopyAssignment: 5699 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5700 case CXXDestructor: 5701 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5702 default: 5703 assert(0 && "unexpected special member"); return; 5704 } 5705 5706 // Check for nontrivial bases (and recurse). 5707 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5708 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5709 assert(BaseRT && "Don't know how to handle dependent bases"); 5710 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5711 if (!(BaseRecTy->*hasTrivial)()) { 5712 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5713 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5714 DiagnoseNontrivial(BaseRT, member); 5715 return; 5716 } 5717 } 5718 5719 // Check for nontrivial members (and recurse). 5720 typedef RecordDecl::field_iterator field_iter; 5721 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5722 ++fi) { 5723 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5724 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5725 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5726 5727 if (!(EltRD->*hasTrivial)()) { 5728 SourceLocation FLoc = (*fi)->getLocation(); 5729 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5730 DiagnoseNontrivial(EltRT, member); 5731 return; 5732 } 5733 } 5734 } 5735 5736 assert(0 && "found no explanation for non-trivial member"); 5737} 5738 5739/// TranslateIvarVisibility - Translate visibility from a token ID to an 5740/// AST enum value. 5741static ObjCIvarDecl::AccessControl 5742TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5743 switch (ivarVisibility) { 5744 default: assert(0 && "Unknown visitibility kind"); 5745 case tok::objc_private: return ObjCIvarDecl::Private; 5746 case tok::objc_public: return ObjCIvarDecl::Public; 5747 case tok::objc_protected: return ObjCIvarDecl::Protected; 5748 case tok::objc_package: return ObjCIvarDecl::Package; 5749 } 5750} 5751 5752/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5753/// in order to create an IvarDecl object for it. 5754Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5755 SourceLocation DeclStart, 5756 DeclPtrTy IntfDecl, 5757 Declarator &D, ExprTy *BitfieldWidth, 5758 tok::ObjCKeywordKind Visibility) { 5759 5760 IdentifierInfo *II = D.getIdentifier(); 5761 Expr *BitWidth = (Expr*)BitfieldWidth; 5762 SourceLocation Loc = DeclStart; 5763 if (II) Loc = D.getIdentifierLoc(); 5764 5765 // FIXME: Unnamed fields can be handled in various different ways, for 5766 // example, unnamed unions inject all members into the struct namespace! 5767 5768 TypeSourceInfo *TInfo = 0; 5769 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5770 5771 if (BitWidth) { 5772 // 6.7.2.1p3, 6.7.2.1p4 5773 if (VerifyBitField(Loc, II, T, BitWidth)) { 5774 D.setInvalidType(); 5775 DeleteExpr(BitWidth); 5776 BitWidth = 0; 5777 } 5778 } else { 5779 // Not a bitfield. 5780 5781 // validate II. 5782 5783 } 5784 5785 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5786 // than a variably modified type. 5787 if (T->isVariablyModifiedType()) { 5788 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5789 D.setInvalidType(); 5790 } 5791 5792 // Get the visibility (access control) for this ivar. 5793 ObjCIvarDecl::AccessControl ac = 5794 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5795 : ObjCIvarDecl::None; 5796 // Must set ivar's DeclContext to its enclosing interface. 5797 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 5798 ObjCContainerDecl *EnclosingContext; 5799 if (ObjCImplementationDecl *IMPDecl = 5800 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5801 // Case of ivar declared in an implementation. Context is that of its class. 5802 EnclosingContext = IMPDecl->getClassInterface(); 5803 assert(EnclosingContext && "Implementation has no class interface!"); 5804 } else { 5805 if (ObjCCategoryDecl *CDecl = 5806 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 5807 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 5808 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 5809 return DeclPtrTy(); 5810 } 5811 } 5812 EnclosingContext = EnclosingDecl; 5813 } 5814 5815 // Construct the decl. 5816 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5817 EnclosingContext, Loc, II, T, 5818 TInfo, ac, (Expr *)BitfieldWidth); 5819 5820 if (II) { 5821 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5822 ForRedeclaration); 5823 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5824 && !isa<TagDecl>(PrevDecl)) { 5825 Diag(Loc, diag::err_duplicate_member) << II; 5826 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5827 NewID->setInvalidDecl(); 5828 } 5829 } 5830 5831 // Process attributes attached to the ivar. 5832 ProcessDeclAttributes(S, NewID, D); 5833 5834 if (D.isInvalidType()) 5835 NewID->setInvalidDecl(); 5836 5837 if (II) { 5838 // FIXME: When interfaces are DeclContexts, we'll need to add 5839 // these to the interface. 5840 S->AddDecl(DeclPtrTy::make(NewID)); 5841 IdResolver.AddDecl(NewID); 5842 } 5843 5844 return DeclPtrTy::make(NewID); 5845} 5846 5847void Sema::ActOnFields(Scope* S, 5848 SourceLocation RecLoc, DeclPtrTy RecDecl, 5849 DeclPtrTy *Fields, unsigned NumFields, 5850 SourceLocation LBrac, SourceLocation RBrac, 5851 AttributeList *Attr) { 5852 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5853 assert(EnclosingDecl && "missing record or interface decl"); 5854 5855 // If the decl this is being inserted into is invalid, then it may be a 5856 // redeclaration or some other bogus case. Don't try to add fields to it. 5857 if (EnclosingDecl->isInvalidDecl()) { 5858 // FIXME: Deallocate fields? 5859 return; 5860 } 5861 5862 5863 // Verify that all the fields are okay. 5864 unsigned NumNamedMembers = 0; 5865 llvm::SmallVector<FieldDecl*, 32> RecFields; 5866 5867 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5868 for (unsigned i = 0; i != NumFields; ++i) { 5869 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5870 5871 // Get the type for the field. 5872 Type *FDTy = FD->getType().getTypePtr(); 5873 5874 if (!FD->isAnonymousStructOrUnion()) { 5875 // Remember all fields written by the user. 5876 RecFields.push_back(FD); 5877 } 5878 5879 // If the field is already invalid for some reason, don't emit more 5880 // diagnostics about it. 5881 if (FD->isInvalidDecl()) { 5882 EnclosingDecl->setInvalidDecl(); 5883 continue; 5884 } 5885 5886 // C99 6.7.2.1p2: 5887 // A structure or union shall not contain a member with 5888 // incomplete or function type (hence, a structure shall not 5889 // contain an instance of itself, but may contain a pointer to 5890 // an instance of itself), except that the last member of a 5891 // structure with more than one named member may have incomplete 5892 // array type; such a structure (and any union containing, 5893 // possibly recursively, a member that is such a structure) 5894 // shall not be a member of a structure or an element of an 5895 // array. 5896 if (FDTy->isFunctionType()) { 5897 // Field declared as a function. 5898 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5899 << FD->getDeclName(); 5900 FD->setInvalidDecl(); 5901 EnclosingDecl->setInvalidDecl(); 5902 continue; 5903 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5904 Record && Record->isStruct()) { 5905 // Flexible array member. 5906 if (NumNamedMembers < 1) { 5907 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5908 << FD->getDeclName(); 5909 FD->setInvalidDecl(); 5910 EnclosingDecl->setInvalidDecl(); 5911 continue; 5912 } 5913 // Okay, we have a legal flexible array member at the end of the struct. 5914 if (Record) 5915 Record->setHasFlexibleArrayMember(true); 5916 } else if (!FDTy->isDependentType() && 5917 RequireCompleteType(FD->getLocation(), FD->getType(), 5918 diag::err_field_incomplete)) { 5919 // Incomplete type 5920 FD->setInvalidDecl(); 5921 EnclosingDecl->setInvalidDecl(); 5922 continue; 5923 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5924 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5925 // If this is a member of a union, then entire union becomes "flexible". 5926 if (Record && Record->isUnion()) { 5927 Record->setHasFlexibleArrayMember(true); 5928 } else { 5929 // If this is a struct/class and this is not the last element, reject 5930 // it. Note that GCC supports variable sized arrays in the middle of 5931 // structures. 5932 if (i != NumFields-1) 5933 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5934 << FD->getDeclName() << FD->getType(); 5935 else { 5936 // We support flexible arrays at the end of structs in 5937 // other structs as an extension. 5938 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5939 << FD->getDeclName(); 5940 if (Record) 5941 Record->setHasFlexibleArrayMember(true); 5942 } 5943 } 5944 } 5945 if (Record && FDTTy->getDecl()->hasObjectMember()) 5946 Record->setHasObjectMember(true); 5947 } else if (FDTy->isObjCInterfaceType()) { 5948 /// A field cannot be an Objective-c object 5949 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5950 FD->setInvalidDecl(); 5951 EnclosingDecl->setInvalidDecl(); 5952 continue; 5953 } else if (getLangOptions().ObjC1 && 5954 getLangOptions().getGCMode() != LangOptions::NonGC && 5955 Record && 5956 (FD->getType()->isObjCObjectPointerType() || 5957 FD->getType().isObjCGCStrong())) 5958 Record->setHasObjectMember(true); 5959 // Keep track of the number of named members. 5960 if (FD->getIdentifier()) 5961 ++NumNamedMembers; 5962 } 5963 5964 // Okay, we successfully defined 'Record'. 5965 if (Record) { 5966 Record->completeDefinition(); 5967 } else { 5968 ObjCIvarDecl **ClsFields = 5969 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5970 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5971 ID->setLocEnd(RBrac); 5972 // Add ivar's to class's DeclContext. 5973 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5974 ClsFields[i]->setLexicalDeclContext(ID); 5975 ID->addDecl(ClsFields[i]); 5976 } 5977 // Must enforce the rule that ivars in the base classes may not be 5978 // duplicates. 5979 if (ID->getSuperClass()) 5980 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 5981 } else if (ObjCImplementationDecl *IMPDecl = 5982 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5983 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5984 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5985 // Ivar declared in @implementation never belongs to the implementation. 5986 // Only it is in implementation's lexical context. 5987 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5988 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5989 } else if (ObjCCategoryDecl *CDecl = 5990 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 5991 // case of ivars in class extension; all other cases have been 5992 // reported as errors elsewhere. 5993 // FIXME. Class extension does not have a LocEnd field. 5994 // CDecl->setLocEnd(RBrac); 5995 // Add ivar's to class extension's DeclContext. 5996 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5997 ClsFields[i]->setLexicalDeclContext(CDecl); 5998 CDecl->addDecl(ClsFields[i]); 5999 } 6000 } 6001 } 6002 6003 if (Attr) 6004 ProcessDeclAttributeList(S, Record, Attr); 6005} 6006 6007/// \brief Determine whether the given integral value is representable within 6008/// the given type T. 6009static bool isRepresentableIntegerValue(ASTContext &Context, 6010 llvm::APSInt &Value, 6011 QualType T) { 6012 assert(T->isIntegralType() && "Integral type required!"); 6013 unsigned BitWidth = Context.getIntWidth(T); 6014 6015 if (Value.isUnsigned() || Value.isNonNegative()) 6016 return Value.getActiveBits() < BitWidth; 6017 6018 return Value.getMinSignedBits() <= BitWidth; 6019} 6020 6021// \brief Given an integral type, return the next larger integral type 6022// (or a NULL type of no such type exists). 6023static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6024 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6025 // enum checking below. 6026 assert(T->isIntegralType() && "Integral type required!"); 6027 const unsigned NumTypes = 4; 6028 QualType SignedIntegralTypes[NumTypes] = { 6029 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6030 }; 6031 QualType UnsignedIntegralTypes[NumTypes] = { 6032 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6033 Context.UnsignedLongLongTy 6034 }; 6035 6036 unsigned BitWidth = Context.getTypeSize(T); 6037 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6038 : UnsignedIntegralTypes; 6039 for (unsigned I = 0; I != NumTypes; ++I) 6040 if (Context.getTypeSize(Types[I]) > BitWidth) 6041 return Types[I]; 6042 6043 return QualType(); 6044} 6045 6046EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6047 EnumConstantDecl *LastEnumConst, 6048 SourceLocation IdLoc, 6049 IdentifierInfo *Id, 6050 ExprArg val) { 6051 Expr *Val = (Expr *)val.get(); 6052 6053 unsigned IntWidth = Context.Target.getIntWidth(); 6054 llvm::APSInt EnumVal(IntWidth); 6055 QualType EltTy; 6056 if (Val) { 6057 if (Enum->isDependentType() || Val->isTypeDependent()) 6058 EltTy = Context.DependentTy; 6059 else { 6060 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6061 SourceLocation ExpLoc; 6062 if (!Val->isValueDependent() && 6063 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6064 Val = 0; 6065 } else { 6066 if (!getLangOptions().CPlusPlus) { 6067 // C99 6.7.2.2p2: 6068 // The expression that defines the value of an enumeration constant 6069 // shall be an integer constant expression that has a value 6070 // representable as an int. 6071 6072 // Complain if the value is not representable in an int. 6073 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6074 Diag(IdLoc, diag::ext_enum_value_not_int) 6075 << EnumVal.toString(10) << Val->getSourceRange() 6076 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6077 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6078 // Force the type of the expression to 'int'. 6079 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6080 6081 if (Val != val.get()) { 6082 val.release(); 6083 val = Val; 6084 } 6085 } 6086 } 6087 6088 // C++0x [dcl.enum]p5: 6089 // If the underlying type is not fixed, the type of each enumerator 6090 // is the type of its initializing value: 6091 // - If an initializer is specified for an enumerator, the 6092 // initializing value has the same type as the expression. 6093 EltTy = Val->getType(); 6094 } 6095 } 6096 } 6097 6098 if (!Val) { 6099 if (Enum->isDependentType()) 6100 EltTy = Context.DependentTy; 6101 else if (!LastEnumConst) { 6102 // C++0x [dcl.enum]p5: 6103 // If the underlying type is not fixed, the type of each enumerator 6104 // is the type of its initializing value: 6105 // - If no initializer is specified for the first enumerator, the 6106 // initializing value has an unspecified integral type. 6107 // 6108 // GCC uses 'int' for its unspecified integral type, as does 6109 // C99 6.7.2.2p3. 6110 EltTy = Context.IntTy; 6111 } else { 6112 // Assign the last value + 1. 6113 EnumVal = LastEnumConst->getInitVal(); 6114 ++EnumVal; 6115 EltTy = LastEnumConst->getType(); 6116 6117 // Check for overflow on increment. 6118 if (EnumVal < LastEnumConst->getInitVal()) { 6119 // C++0x [dcl.enum]p5: 6120 // If the underlying type is not fixed, the type of each enumerator 6121 // is the type of its initializing value: 6122 // 6123 // - Otherwise the type of the initializing value is the same as 6124 // the type of the initializing value of the preceding enumerator 6125 // unless the incremented value is not representable in that type, 6126 // in which case the type is an unspecified integral type 6127 // sufficient to contain the incremented value. If no such type 6128 // exists, the program is ill-formed. 6129 QualType T = getNextLargerIntegralType(Context, EltTy); 6130 if (T.isNull()) { 6131 // There is no integral type larger enough to represent this 6132 // value. Complain, then allow the value to wrap around. 6133 EnumVal = LastEnumConst->getInitVal(); 6134 EnumVal.zext(EnumVal.getBitWidth() * 2); 6135 Diag(IdLoc, diag::warn_enumerator_too_large) 6136 << EnumVal.toString(10); 6137 } else { 6138 EltTy = T; 6139 } 6140 6141 // Retrieve the last enumerator's value, extent that type to the 6142 // type that is supposed to be large enough to represent the incremented 6143 // value, then increment. 6144 EnumVal = LastEnumConst->getInitVal(); 6145 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6146 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6147 ++EnumVal; 6148 6149 // If we're not in C++, diagnose the overflow of enumerator values, 6150 // which in C99 means that the enumerator value is not representable in 6151 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6152 // permits enumerator values that are representable in some larger 6153 // integral type. 6154 if (!getLangOptions().CPlusPlus && !T.isNull()) 6155 Diag(IdLoc, diag::warn_enum_value_overflow); 6156 } else if (!getLangOptions().CPlusPlus && 6157 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6158 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6159 Diag(IdLoc, diag::ext_enum_value_not_int) 6160 << EnumVal.toString(10) << 1; 6161 } 6162 } 6163 } 6164 6165 if (!EltTy->isDependentType()) { 6166 // Make the enumerator value match the signedness and size of the 6167 // enumerator's type. 6168 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6169 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6170 } 6171 6172 val.release(); 6173 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6174 Val, EnumVal); 6175} 6176 6177 6178Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6179 DeclPtrTy lastEnumConst, 6180 SourceLocation IdLoc, 6181 IdentifierInfo *Id, 6182 SourceLocation EqualLoc, ExprTy *val) { 6183 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6184 EnumConstantDecl *LastEnumConst = 6185 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6186 Expr *Val = static_cast<Expr*>(val); 6187 6188 // The scope passed in may not be a decl scope. Zip up the scope tree until 6189 // we find one that is. 6190 S = getNonFieldDeclScope(S); 6191 6192 // Verify that there isn't already something declared with this name in this 6193 // scope. 6194 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6195 ForRedeclaration); 6196 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6197 // Maybe we will complain about the shadowed template parameter. 6198 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6199 // Just pretend that we didn't see the previous declaration. 6200 PrevDecl = 0; 6201 } 6202 6203 if (PrevDecl) { 6204 // When in C++, we may get a TagDecl with the same name; in this case the 6205 // enum constant will 'hide' the tag. 6206 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6207 "Received TagDecl when not in C++!"); 6208 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6209 if (isa<EnumConstantDecl>(PrevDecl)) 6210 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6211 else 6212 Diag(IdLoc, diag::err_redefinition) << Id; 6213 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6214 if (Val) Val->Destroy(Context); 6215 return DeclPtrTy(); 6216 } 6217 } 6218 6219 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6220 IdLoc, Id, Owned(Val)); 6221 6222 // Register this decl in the current scope stack. 6223 if (New) { 6224 New->setAccess(TheEnumDecl->getAccess()); 6225 PushOnScopeChains(New, S); 6226 } 6227 6228 return DeclPtrTy::make(New); 6229} 6230 6231void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6232 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6233 DeclPtrTy *Elements, unsigned NumElements, 6234 Scope *S, AttributeList *Attr) { 6235 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6236 QualType EnumType = Context.getTypeDeclType(Enum); 6237 6238 if (Attr) 6239 ProcessDeclAttributeList(S, Enum, Attr); 6240 6241 if (Enum->isDependentType()) { 6242 for (unsigned i = 0; i != NumElements; ++i) { 6243 EnumConstantDecl *ECD = 6244 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6245 if (!ECD) continue; 6246 6247 ECD->setType(EnumType); 6248 } 6249 6250 Enum->completeDefinition(Context.DependentTy, Context.DependentTy); 6251 return; 6252 } 6253 6254 // TODO: If the result value doesn't fit in an int, it must be a long or long 6255 // long value. ISO C does not support this, but GCC does as an extension, 6256 // emit a warning. 6257 unsigned IntWidth = Context.Target.getIntWidth(); 6258 unsigned CharWidth = Context.Target.getCharWidth(); 6259 unsigned ShortWidth = Context.Target.getShortWidth(); 6260 6261 // Verify that all the values are okay, compute the size of the values, and 6262 // reverse the list. 6263 unsigned NumNegativeBits = 0; 6264 unsigned NumPositiveBits = 0; 6265 6266 // Keep track of whether all elements have type int. 6267 bool AllElementsInt = true; 6268 6269 for (unsigned i = 0; i != NumElements; ++i) { 6270 EnumConstantDecl *ECD = 6271 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6272 if (!ECD) continue; // Already issued a diagnostic. 6273 6274 const llvm::APSInt &InitVal = ECD->getInitVal(); 6275 6276 // Keep track of the size of positive and negative values. 6277 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6278 NumPositiveBits = std::max(NumPositiveBits, 6279 (unsigned)InitVal.getActiveBits()); 6280 else 6281 NumNegativeBits = std::max(NumNegativeBits, 6282 (unsigned)InitVal.getMinSignedBits()); 6283 6284 // Keep track of whether every enum element has type int (very commmon). 6285 if (AllElementsInt) 6286 AllElementsInt = ECD->getType() == Context.IntTy; 6287 } 6288 6289 // Figure out the type that should be used for this enum. 6290 // FIXME: Support -fshort-enums. 6291 QualType BestType; 6292 unsigned BestWidth; 6293 6294 // C++0x N3000 [conv.prom]p3: 6295 // An rvalue of an unscoped enumeration type whose underlying 6296 // type is not fixed can be converted to an rvalue of the first 6297 // of the following types that can represent all the values of 6298 // the enumeration: int, unsigned int, long int, unsigned long 6299 // int, long long int, or unsigned long long int. 6300 // C99 6.4.4.3p2: 6301 // An identifier declared as an enumeration constant has type int. 6302 // The C99 rule is modified by a gcc extension 6303 QualType BestPromotionType; 6304 6305 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6306 6307 if (NumNegativeBits) { 6308 // If there is a negative value, figure out the smallest integer type (of 6309 // int/long/longlong) that fits. 6310 // If it's packed, check also if it fits a char or a short. 6311 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6312 BestType = Context.SignedCharTy; 6313 BestWidth = CharWidth; 6314 } else if (Packed && NumNegativeBits <= ShortWidth && 6315 NumPositiveBits < ShortWidth) { 6316 BestType = Context.ShortTy; 6317 BestWidth = ShortWidth; 6318 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6319 BestType = Context.IntTy; 6320 BestWidth = IntWidth; 6321 } else { 6322 BestWidth = Context.Target.getLongWidth(); 6323 6324 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6325 BestType = Context.LongTy; 6326 } else { 6327 BestWidth = Context.Target.getLongLongWidth(); 6328 6329 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6330 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6331 BestType = Context.LongLongTy; 6332 } 6333 } 6334 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6335 } else { 6336 // If there is no negative value, figure out the smallest type that fits 6337 // all of the enumerator values. 6338 // If it's packed, check also if it fits a char or a short. 6339 if (Packed && NumPositiveBits <= CharWidth) { 6340 BestType = Context.UnsignedCharTy; 6341 BestPromotionType = Context.IntTy; 6342 BestWidth = CharWidth; 6343 } else if (Packed && NumPositiveBits <= ShortWidth) { 6344 BestType = Context.UnsignedShortTy; 6345 BestPromotionType = Context.IntTy; 6346 BestWidth = ShortWidth; 6347 } else if (NumPositiveBits <= IntWidth) { 6348 BestType = Context.UnsignedIntTy; 6349 BestWidth = IntWidth; 6350 BestPromotionType 6351 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6352 ? Context.UnsignedIntTy : Context.IntTy; 6353 } else if (NumPositiveBits <= 6354 (BestWidth = Context.Target.getLongWidth())) { 6355 BestType = Context.UnsignedLongTy; 6356 BestPromotionType 6357 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6358 ? Context.UnsignedLongTy : Context.LongTy; 6359 } else { 6360 BestWidth = Context.Target.getLongLongWidth(); 6361 assert(NumPositiveBits <= BestWidth && 6362 "How could an initializer get larger than ULL?"); 6363 BestType = Context.UnsignedLongLongTy; 6364 BestPromotionType 6365 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6366 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6367 } 6368 } 6369 6370 // Loop over all of the enumerator constants, changing their types to match 6371 // the type of the enum if needed. 6372 for (unsigned i = 0; i != NumElements; ++i) { 6373 EnumConstantDecl *ECD = 6374 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6375 if (!ECD) continue; // Already issued a diagnostic. 6376 6377 // Standard C says the enumerators have int type, but we allow, as an 6378 // extension, the enumerators to be larger than int size. If each 6379 // enumerator value fits in an int, type it as an int, otherwise type it the 6380 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6381 // that X has type 'int', not 'unsigned'. 6382 6383 // Determine whether the value fits into an int. 6384 llvm::APSInt InitVal = ECD->getInitVal(); 6385 6386 // If it fits into an integer type, force it. Otherwise force it to match 6387 // the enum decl type. 6388 QualType NewTy; 6389 unsigned NewWidth; 6390 bool NewSign; 6391 if (!getLangOptions().CPlusPlus && 6392 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6393 NewTy = Context.IntTy; 6394 NewWidth = IntWidth; 6395 NewSign = true; 6396 } else if (ECD->getType() == BestType) { 6397 // Already the right type! 6398 if (getLangOptions().CPlusPlus) 6399 // C++ [dcl.enum]p4: Following the closing brace of an 6400 // enum-specifier, each enumerator has the type of its 6401 // enumeration. 6402 ECD->setType(EnumType); 6403 continue; 6404 } else { 6405 NewTy = BestType; 6406 NewWidth = BestWidth; 6407 NewSign = BestType->isSignedIntegerType(); 6408 } 6409 6410 // Adjust the APSInt value. 6411 InitVal.extOrTrunc(NewWidth); 6412 InitVal.setIsSigned(NewSign); 6413 ECD->setInitVal(InitVal); 6414 6415 // Adjust the Expr initializer and type. 6416 if (ECD->getInitExpr()) 6417 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6418 CastExpr::CK_IntegralCast, 6419 ECD->getInitExpr(), 6420 /*isLvalue=*/false)); 6421 if (getLangOptions().CPlusPlus) 6422 // C++ [dcl.enum]p4: Following the closing brace of an 6423 // enum-specifier, each enumerator has the type of its 6424 // enumeration. 6425 ECD->setType(EnumType); 6426 else 6427 ECD->setType(NewTy); 6428 } 6429 6430 Enum->completeDefinition(BestType, BestPromotionType); 6431} 6432 6433Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6434 ExprArg expr) { 6435 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6436 6437 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6438 Loc, AsmString); 6439 CurContext->addDecl(New); 6440 return DeclPtrTy::make(New); 6441} 6442 6443void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6444 SourceLocation PragmaLoc, 6445 SourceLocation NameLoc) { 6446 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6447 6448 if (PrevDecl) { 6449 PrevDecl->addAttr(::new (Context) WeakAttr()); 6450 } else { 6451 (void)WeakUndeclaredIdentifiers.insert( 6452 std::pair<IdentifierInfo*,WeakInfo> 6453 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6454 } 6455} 6456 6457void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6458 IdentifierInfo* AliasName, 6459 SourceLocation PragmaLoc, 6460 SourceLocation NameLoc, 6461 SourceLocation AliasNameLoc) { 6462 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6463 LookupOrdinaryName); 6464 WeakInfo W = WeakInfo(Name, NameLoc); 6465 6466 if (PrevDecl) { 6467 if (!PrevDecl->hasAttr<AliasAttr>()) 6468 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6469 DeclApplyPragmaWeak(TUScope, ND, W); 6470 } else { 6471 (void)WeakUndeclaredIdentifiers.insert( 6472 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6473 } 6474} 6475