SemaDecl.cpp revision 66dd9394994654b5af2c62ed24f311432bacede5
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, 721 FunctionDecl::None, false, 722 /*hasPrototype=*/true); 723 New->setImplicit(); 724 725 // Create Decl objects for each parameter, adding them to the 726 // FunctionDecl. 727 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 728 llvm::SmallVector<ParmVarDecl*, 16> Params; 729 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 730 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 731 FT->getArgType(i), /*TInfo=*/0, 732 VarDecl::None, VarDecl::None, 0)); 733 New->setParams(Params.data(), Params.size()); 734 } 735 736 AddKnownFunctionAttributes(New); 737 738 // TUScope is the translation-unit scope to insert this function into. 739 // FIXME: This is hideous. We need to teach PushOnScopeChains to 740 // relate Scopes to DeclContexts, and probably eliminate CurContext 741 // entirely, but we're not there yet. 742 DeclContext *SavedContext = CurContext; 743 CurContext = Context.getTranslationUnitDecl(); 744 PushOnScopeChains(New, TUScope); 745 CurContext = SavedContext; 746 return New; 747} 748 749/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 750/// same name and scope as a previous declaration 'Old'. Figure out 751/// how to resolve this situation, merging decls or emitting 752/// diagnostics as appropriate. If there was an error, set New to be invalid. 753/// 754void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 755 // If the new decl is known invalid already, don't bother doing any 756 // merging checks. 757 if (New->isInvalidDecl()) return; 758 759 // Allow multiple definitions for ObjC built-in typedefs. 760 // FIXME: Verify the underlying types are equivalent! 761 if (getLangOptions().ObjC1) { 762 const IdentifierInfo *TypeID = New->getIdentifier(); 763 switch (TypeID->getLength()) { 764 default: break; 765 case 2: 766 if (!TypeID->isStr("id")) 767 break; 768 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 769 // Install the built-in type for 'id', ignoring the current definition. 770 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 771 return; 772 case 5: 773 if (!TypeID->isStr("Class")) 774 break; 775 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 776 // Install the built-in type for 'Class', ignoring the current definition. 777 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 778 return; 779 case 3: 780 if (!TypeID->isStr("SEL")) 781 break; 782 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 783 // Install the built-in type for 'SEL', ignoring the current definition. 784 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 785 return; 786 case 8: 787 if (!TypeID->isStr("Protocol")) 788 break; 789 Context.setObjCProtoType(New->getUnderlyingType()); 790 return; 791 } 792 // Fall through - the typedef name was not a builtin type. 793 } 794 795 // Verify the old decl was also a type. 796 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 797 if (!Old) { 798 Diag(New->getLocation(), diag::err_redefinition_different_kind) 799 << New->getDeclName(); 800 801 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 802 if (OldD->getLocation().isValid()) 803 Diag(OldD->getLocation(), diag::note_previous_definition); 804 805 return New->setInvalidDecl(); 806 } 807 808 // If the old declaration is invalid, just give up here. 809 if (Old->isInvalidDecl()) 810 return New->setInvalidDecl(); 811 812 // Determine the "old" type we'll use for checking and diagnostics. 813 QualType OldType; 814 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 815 OldType = OldTypedef->getUnderlyingType(); 816 else 817 OldType = Context.getTypeDeclType(Old); 818 819 // If the typedef types are not identical, reject them in all languages and 820 // with any extensions enabled. 821 822 if (OldType != New->getUnderlyingType() && 823 Context.getCanonicalType(OldType) != 824 Context.getCanonicalType(New->getUnderlyingType())) { 825 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 826 << New->getUnderlyingType() << OldType; 827 if (Old->getLocation().isValid()) 828 Diag(Old->getLocation(), diag::note_previous_definition); 829 return New->setInvalidDecl(); 830 } 831 832 // The types match. Link up the redeclaration chain if the old 833 // declaration was a typedef. 834 // FIXME: this is a potential source of wierdness if the type 835 // spellings don't match exactly. 836 if (isa<TypedefDecl>(Old)) 837 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 838 839 if (getLangOptions().Microsoft) 840 return; 841 842 if (getLangOptions().CPlusPlus) { 843 // C++ [dcl.typedef]p2: 844 // In a given non-class scope, a typedef specifier can be used to 845 // redefine the name of any type declared in that scope to refer 846 // to the type to which it already refers. 847 if (!isa<CXXRecordDecl>(CurContext)) 848 return; 849 850 // C++0x [dcl.typedef]p4: 851 // In a given class scope, a typedef specifier can be used to redefine 852 // any class-name declared in that scope that is not also a typedef-name 853 // to refer to the type to which it already refers. 854 // 855 // This wording came in via DR424, which was a correction to the 856 // wording in DR56, which accidentally banned code like: 857 // 858 // struct S { 859 // typedef struct A { } A; 860 // }; 861 // 862 // in the C++03 standard. We implement the C++0x semantics, which 863 // allow the above but disallow 864 // 865 // struct S { 866 // typedef int I; 867 // typedef int I; 868 // }; 869 // 870 // since that was the intent of DR56. 871 if (!isa<TypedefDecl >(Old)) 872 return; 873 874 Diag(New->getLocation(), diag::err_redefinition) 875 << New->getDeclName(); 876 Diag(Old->getLocation(), diag::note_previous_definition); 877 return New->setInvalidDecl(); 878 } 879 880 // If we have a redefinition of a typedef in C, emit a warning. This warning 881 // is normally mapped to an error, but can be controlled with 882 // -Wtypedef-redefinition. If either the original or the redefinition is 883 // in a system header, don't emit this for compatibility with GCC. 884 if (getDiagnostics().getSuppressSystemWarnings() && 885 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 886 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 887 return; 888 889 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 890 << New->getDeclName(); 891 Diag(Old->getLocation(), diag::note_previous_definition); 892 return; 893} 894 895/// DeclhasAttr - returns true if decl Declaration already has the target 896/// attribute. 897static bool 898DeclHasAttr(const Decl *decl, const Attr *target) { 899 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 900 if (attr->getKind() == target->getKind()) 901 return true; 902 903 return false; 904} 905 906/// MergeAttributes - append attributes from the Old decl to the New one. 907static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 908 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 909 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 910 Attr *NewAttr = attr->clone(C); 911 NewAttr->setInherited(true); 912 New->addAttr(NewAttr); 913 } 914 } 915} 916 917/// Used in MergeFunctionDecl to keep track of function parameters in 918/// C. 919struct GNUCompatibleParamWarning { 920 ParmVarDecl *OldParm; 921 ParmVarDecl *NewParm; 922 QualType PromotedType; 923}; 924 925 926/// getSpecialMember - get the special member enum for a method. 927Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 928 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 929 if (Ctor->isCopyConstructor()) 930 return Sema::CXXCopyConstructor; 931 932 return Sema::CXXConstructor; 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(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, VarDecl::None, 1164 0); 1165 Param->setImplicit(); 1166 Params.push_back(Param); 1167 } 1168 1169 New->setParams(Params.data(), Params.size()); 1170 } 1171 1172 return MergeCompatibleFunctionDecls(New, Old); 1173 } 1174 1175 // GNU C permits a K&R definition to follow a prototype declaration 1176 // if the declared types of the parameters in the K&R definition 1177 // match the types in the prototype declaration, even when the 1178 // promoted types of the parameters from the K&R definition differ 1179 // from the types in the prototype. GCC then keeps the types from 1180 // the prototype. 1181 // 1182 // If a variadic prototype is followed by a non-variadic K&R definition, 1183 // the K&R definition becomes variadic. This is sort of an edge case, but 1184 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1185 // C99 6.9.1p8. 1186 if (!getLangOptions().CPlusPlus && 1187 Old->hasPrototype() && !New->hasPrototype() && 1188 New->getType()->getAs<FunctionProtoType>() && 1189 Old->getNumParams() == New->getNumParams()) { 1190 llvm::SmallVector<QualType, 16> ArgTypes; 1191 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1192 const FunctionProtoType *OldProto 1193 = Old->getType()->getAs<FunctionProtoType>(); 1194 const FunctionProtoType *NewProto 1195 = New->getType()->getAs<FunctionProtoType>(); 1196 1197 // Determine whether this is the GNU C extension. 1198 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1199 NewProto->getResultType()); 1200 bool LooseCompatible = !MergedReturn.isNull(); 1201 for (unsigned Idx = 0, End = Old->getNumParams(); 1202 LooseCompatible && Idx != End; ++Idx) { 1203 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1204 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1205 if (Context.typesAreCompatible(OldParm->getType(), 1206 NewProto->getArgType(Idx))) { 1207 ArgTypes.push_back(NewParm->getType()); 1208 } else if (Context.typesAreCompatible(OldParm->getType(), 1209 NewParm->getType())) { 1210 GNUCompatibleParamWarning Warn 1211 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1212 Warnings.push_back(Warn); 1213 ArgTypes.push_back(NewParm->getType()); 1214 } else 1215 LooseCompatible = false; 1216 } 1217 1218 if (LooseCompatible) { 1219 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1220 Diag(Warnings[Warn].NewParm->getLocation(), 1221 diag::ext_param_promoted_not_compatible_with_prototype) 1222 << Warnings[Warn].PromotedType 1223 << Warnings[Warn].OldParm->getType(); 1224 Diag(Warnings[Warn].OldParm->getLocation(), 1225 diag::note_previous_declaration); 1226 } 1227 1228 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1229 ArgTypes.size(), 1230 OldProto->isVariadic(), 0, 1231 false, false, 0, 0, 1232 OldProto->getExtInfo())); 1233 return MergeCompatibleFunctionDecls(New, Old); 1234 } 1235 1236 // Fall through to diagnose conflicting types. 1237 } 1238 1239 // A function that has already been declared has been redeclared or defined 1240 // with a different type- show appropriate diagnostic 1241 if (unsigned BuiltinID = Old->getBuiltinID()) { 1242 // The user has declared a builtin function with an incompatible 1243 // signature. 1244 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1245 // The function the user is redeclaring is a library-defined 1246 // function like 'malloc' or 'printf'. Warn about the 1247 // redeclaration, then pretend that we don't know about this 1248 // library built-in. 1249 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1250 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1251 << Old << Old->getType(); 1252 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1253 Old->setInvalidDecl(); 1254 return false; 1255 } 1256 1257 PrevDiag = diag::note_previous_builtin_declaration; 1258 } 1259 1260 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1261 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1262 return true; 1263} 1264 1265/// \brief Completes the merge of two function declarations that are 1266/// known to be compatible. 1267/// 1268/// This routine handles the merging of attributes and other 1269/// properties of function declarations form the old declaration to 1270/// the new declaration, once we know that New is in fact a 1271/// redeclaration of Old. 1272/// 1273/// \returns false 1274bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1275 // Merge the attributes 1276 MergeAttributes(New, Old, Context); 1277 1278 // Merge the storage class. 1279 if (Old->getStorageClass() != FunctionDecl::Extern && 1280 Old->getStorageClass() != FunctionDecl::None) 1281 New->setStorageClass(Old->getStorageClass()); 1282 1283 // Merge "pure" flag. 1284 if (Old->isPure()) 1285 New->setPure(); 1286 1287 // Merge the "deleted" flag. 1288 if (Old->isDeleted()) 1289 New->setDeleted(); 1290 1291 if (getLangOptions().CPlusPlus) 1292 return MergeCXXFunctionDecl(New, Old); 1293 1294 return false; 1295} 1296 1297/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1298/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1299/// situation, merging decls or emitting diagnostics as appropriate. 1300/// 1301/// Tentative definition rules (C99 6.9.2p2) are checked by 1302/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1303/// definitions here, since the initializer hasn't been attached. 1304/// 1305void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1306 // If the new decl is already invalid, don't do any other checking. 1307 if (New->isInvalidDecl()) 1308 return; 1309 1310 // Verify the old decl was also a variable. 1311 VarDecl *Old = 0; 1312 if (!Previous.isSingleResult() || 1313 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1314 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1315 << New->getDeclName(); 1316 Diag(Previous.getRepresentativeDecl()->getLocation(), 1317 diag::note_previous_definition); 1318 return New->setInvalidDecl(); 1319 } 1320 1321 MergeAttributes(New, Old, Context); 1322 1323 // Merge the types 1324 QualType MergedT; 1325 if (getLangOptions().CPlusPlus) { 1326 if (Context.hasSameType(New->getType(), Old->getType())) 1327 MergedT = New->getType(); 1328 // C++ [basic.link]p10: 1329 // [...] the types specified by all declarations referring to a given 1330 // object or function shall be identical, except that declarations for an 1331 // array object can specify array types that differ by the presence or 1332 // absence of a major array bound (8.3.4). 1333 else if (Old->getType()->isIncompleteArrayType() && 1334 New->getType()->isArrayType()) { 1335 CanQual<ArrayType> OldArray 1336 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1337 CanQual<ArrayType> NewArray 1338 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1339 if (OldArray->getElementType() == NewArray->getElementType()) 1340 MergedT = New->getType(); 1341 } else if (Old->getType()->isArrayType() && 1342 New->getType()->isIncompleteArrayType()) { 1343 CanQual<ArrayType> OldArray 1344 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1345 CanQual<ArrayType> NewArray 1346 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1347 if (OldArray->getElementType() == NewArray->getElementType()) 1348 MergedT = Old->getType(); 1349 } 1350 } else { 1351 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1352 } 1353 if (MergedT.isNull()) { 1354 Diag(New->getLocation(), diag::err_redefinition_different_type) 1355 << New->getDeclName(); 1356 Diag(Old->getLocation(), diag::note_previous_definition); 1357 return New->setInvalidDecl(); 1358 } 1359 New->setType(MergedT); 1360 1361 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1362 if (New->getStorageClass() == VarDecl::Static && 1363 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1364 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1365 Diag(Old->getLocation(), diag::note_previous_definition); 1366 return New->setInvalidDecl(); 1367 } 1368 // C99 6.2.2p4: 1369 // For an identifier declared with the storage-class specifier 1370 // extern in a scope in which a prior declaration of that 1371 // identifier is visible,23) if the prior declaration specifies 1372 // internal or external linkage, the linkage of the identifier at 1373 // the later declaration is the same as the linkage specified at 1374 // the prior declaration. If no prior declaration is visible, or 1375 // if the prior declaration specifies no linkage, then the 1376 // identifier has external linkage. 1377 if (New->hasExternalStorage() && Old->hasLinkage()) 1378 /* Okay */; 1379 else if (New->getStorageClass() != VarDecl::Static && 1380 Old->getStorageClass() == VarDecl::Static) { 1381 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1382 Diag(Old->getLocation(), diag::note_previous_definition); 1383 return New->setInvalidDecl(); 1384 } 1385 1386 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1387 1388 // FIXME: The test for external storage here seems wrong? We still 1389 // need to check for mismatches. 1390 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1391 // Don't complain about out-of-line definitions of static members. 1392 !(Old->getLexicalDeclContext()->isRecord() && 1393 !New->getLexicalDeclContext()->isRecord())) { 1394 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1395 Diag(Old->getLocation(), diag::note_previous_definition); 1396 return New->setInvalidDecl(); 1397 } 1398 1399 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1400 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1401 Diag(Old->getLocation(), diag::note_previous_definition); 1402 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1403 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1404 Diag(Old->getLocation(), diag::note_previous_definition); 1405 } 1406 1407 // C++ doesn't have tentative definitions, so go right ahead and check here. 1408 const VarDecl *Def; 1409 if (getLangOptions().CPlusPlus && 1410 New->isThisDeclarationADefinition() == VarDecl::Definition && 1411 (Def = Old->getDefinition())) { 1412 Diag(New->getLocation(), diag::err_redefinition) 1413 << New->getDeclName(); 1414 Diag(Def->getLocation(), diag::note_previous_definition); 1415 New->setInvalidDecl(); 1416 return; 1417 } 1418 1419 // Keep a chain of previous declarations. 1420 New->setPreviousDeclaration(Old); 1421 1422 // Inherit access appropriately. 1423 New->setAccess(Old->getAccess()); 1424} 1425 1426/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1427/// no declarator (e.g. "struct foo;") is parsed. 1428Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1429 // FIXME: Error on auto/register at file scope 1430 // FIXME: Error on inline/virtual/explicit 1431 // FIXME: Warn on useless __thread 1432 // FIXME: Warn on useless const/volatile 1433 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1434 // FIXME: Warn on useless attributes 1435 Decl *TagD = 0; 1436 TagDecl *Tag = 0; 1437 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1438 DS.getTypeSpecType() == DeclSpec::TST_struct || 1439 DS.getTypeSpecType() == DeclSpec::TST_union || 1440 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1441 TagD = static_cast<Decl *>(DS.getTypeRep()); 1442 1443 if (!TagD) // We probably had an error 1444 return DeclPtrTy(); 1445 1446 // Note that the above type specs guarantee that the 1447 // type rep is a Decl, whereas in many of the others 1448 // it's a Type. 1449 Tag = dyn_cast<TagDecl>(TagD); 1450 } 1451 1452 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1453 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1454 // or incomplete types shall not be restrict-qualified." 1455 if (TypeQuals & DeclSpec::TQ_restrict) 1456 Diag(DS.getRestrictSpecLoc(), 1457 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1458 << DS.getSourceRange(); 1459 } 1460 1461 if (DS.isFriendSpecified()) { 1462 // If we're dealing with a class template decl, assume that the 1463 // template routines are handling it. 1464 if (TagD && isa<ClassTemplateDecl>(TagD)) 1465 return DeclPtrTy(); 1466 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1467 } 1468 1469 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1470 // If there are attributes in the DeclSpec, apply them to the record. 1471 if (const AttributeList *AL = DS.getAttributes()) 1472 ProcessDeclAttributeList(S, Record, AL); 1473 1474 if (!Record->getDeclName() && Record->isDefinition() && 1475 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1476 if (getLangOptions().CPlusPlus || 1477 Record->getDeclContext()->isRecord()) 1478 return BuildAnonymousStructOrUnion(S, DS, Record); 1479 1480 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1481 << DS.getSourceRange(); 1482 } 1483 1484 // Microsoft allows unnamed struct/union fields. Don't complain 1485 // about them. 1486 // FIXME: Should we support Microsoft's extensions in this area? 1487 if (Record->getDeclName() && getLangOptions().Microsoft) 1488 return DeclPtrTy::make(Tag); 1489 } 1490 1491 if (!DS.isMissingDeclaratorOk() && 1492 DS.getTypeSpecType() != DeclSpec::TST_error) { 1493 // Warn about typedefs of enums without names, since this is an 1494 // extension in both Microsoft an GNU. 1495 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1496 Tag && isa<EnumDecl>(Tag)) { 1497 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1498 << DS.getSourceRange(); 1499 return DeclPtrTy::make(Tag); 1500 } 1501 1502 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1503 << DS.getSourceRange(); 1504 } 1505 1506 return DeclPtrTy::make(Tag); 1507} 1508 1509/// We are trying to inject an anonymous member into the given scope; 1510/// check if there's an existing declaration that can't be overloaded. 1511/// 1512/// \return true if this is a forbidden redeclaration 1513static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1514 Scope *S, 1515 DeclContext *Owner, 1516 DeclarationName Name, 1517 SourceLocation NameLoc, 1518 unsigned diagnostic) { 1519 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1520 Sema::ForRedeclaration); 1521 if (!SemaRef.LookupName(R, S)) return false; 1522 1523 if (R.getAsSingle<TagDecl>()) 1524 return false; 1525 1526 // Pick a representative declaration. 1527 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1528 if (PrevDecl && Owner->isRecord()) { 1529 RecordDecl *Record = cast<RecordDecl>(Owner); 1530 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1531 return false; 1532 } 1533 1534 SemaRef.Diag(NameLoc, diagnostic) << Name; 1535 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1536 1537 return true; 1538} 1539 1540/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1541/// anonymous struct or union AnonRecord into the owning context Owner 1542/// and scope S. This routine will be invoked just after we realize 1543/// that an unnamed union or struct is actually an anonymous union or 1544/// struct, e.g., 1545/// 1546/// @code 1547/// union { 1548/// int i; 1549/// float f; 1550/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1551/// // f into the surrounding scope.x 1552/// @endcode 1553/// 1554/// This routine is recursive, injecting the names of nested anonymous 1555/// structs/unions into the owning context and scope as well. 1556bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1557 RecordDecl *AnonRecord) { 1558 unsigned diagKind 1559 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1560 : diag::err_anonymous_struct_member_redecl; 1561 1562 bool Invalid = false; 1563 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1564 FEnd = AnonRecord->field_end(); 1565 F != FEnd; ++F) { 1566 if ((*F)->getDeclName()) { 1567 if (CheckAnonMemberRedeclaration(*this, S, Owner, (*F)->getDeclName(), 1568 (*F)->getLocation(), diagKind)) { 1569 // C++ [class.union]p2: 1570 // The names of the members of an anonymous union shall be 1571 // distinct from the names of any other entity in the 1572 // scope in which the anonymous union is declared. 1573 Invalid = true; 1574 } else { 1575 // C++ [class.union]p2: 1576 // For the purpose of name lookup, after the anonymous union 1577 // definition, the members of the anonymous union are 1578 // considered to have been defined in the scope in which the 1579 // anonymous union is declared. 1580 Owner->makeDeclVisibleInContext(*F); 1581 S->AddDecl(DeclPtrTy::make(*F)); 1582 IdResolver.AddDecl(*F); 1583 } 1584 } else if (const RecordType *InnerRecordType 1585 = (*F)->getType()->getAs<RecordType>()) { 1586 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1587 if (InnerRecord->isAnonymousStructOrUnion()) 1588 Invalid = Invalid || 1589 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1590 } 1591 } 1592 1593 return Invalid; 1594} 1595 1596/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1597/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1598/// illegal input values are mapped to VarDecl::None. 1599static VarDecl::StorageClass 1600StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1601 switch (StorageClassSpec) { 1602 case DeclSpec::SCS_unspecified: return VarDecl::None; 1603 case DeclSpec::SCS_extern: return VarDecl::Extern; 1604 case DeclSpec::SCS_static: return VarDecl::Static; 1605 case DeclSpec::SCS_auto: return VarDecl::Auto; 1606 case DeclSpec::SCS_register: return VarDecl::Register; 1607 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1608 // Illegal SCSs map to None: error reporting is up to the caller. 1609 case DeclSpec::SCS_mutable: // Fall through. 1610 case DeclSpec::SCS_typedef: return VarDecl::None; 1611 } 1612 llvm_unreachable("unknown storage class specifier"); 1613} 1614 1615/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1616/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1617/// illegal input values are mapped to FunctionDecl::None. 1618static FunctionDecl::StorageClass 1619StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1620 switch (StorageClassSpec) { 1621 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1622 case DeclSpec::SCS_extern: return FunctionDecl::Extern; 1623 case DeclSpec::SCS_static: return FunctionDecl::Static; 1624 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1625 // Illegal SCSs map to None: error reporting is up to the caller. 1626 case DeclSpec::SCS_auto: // Fall through. 1627 case DeclSpec::SCS_mutable: // Fall through. 1628 case DeclSpec::SCS_register: // Fall through. 1629 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1630 } 1631 llvm_unreachable("unknown storage class specifier"); 1632} 1633 1634/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1635/// anonymous structure or union. Anonymous unions are a C++ feature 1636/// (C++ [class.union]) and a GNU C extension; anonymous structures 1637/// are a GNU C and GNU C++ extension. 1638Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1639 RecordDecl *Record) { 1640 DeclContext *Owner = Record->getDeclContext(); 1641 1642 // Diagnose whether this anonymous struct/union is an extension. 1643 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1644 Diag(Record->getLocation(), diag::ext_anonymous_union); 1645 else if (!Record->isUnion()) 1646 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1647 1648 // C and C++ require different kinds of checks for anonymous 1649 // structs/unions. 1650 bool Invalid = false; 1651 if (getLangOptions().CPlusPlus) { 1652 const char* PrevSpec = 0; 1653 unsigned DiagID; 1654 // C++ [class.union]p3: 1655 // Anonymous unions declared in a named namespace or in the 1656 // global namespace shall be declared static. 1657 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1658 (isa<TranslationUnitDecl>(Owner) || 1659 (isa<NamespaceDecl>(Owner) && 1660 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1661 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1662 Invalid = true; 1663 1664 // Recover by adding 'static'. 1665 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1666 PrevSpec, DiagID); 1667 } 1668 // C++ [class.union]p3: 1669 // A storage class is not allowed in a declaration of an 1670 // anonymous union in a class scope. 1671 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1672 isa<RecordDecl>(Owner)) { 1673 Diag(DS.getStorageClassSpecLoc(), 1674 diag::err_anonymous_union_with_storage_spec); 1675 Invalid = true; 1676 1677 // Recover by removing the storage specifier. 1678 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1679 PrevSpec, DiagID); 1680 } 1681 1682 // C++ [class.union]p2: 1683 // The member-specification of an anonymous union shall only 1684 // define non-static data members. [Note: nested types and 1685 // functions cannot be declared within an anonymous union. ] 1686 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1687 MemEnd = Record->decls_end(); 1688 Mem != MemEnd; ++Mem) { 1689 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1690 // C++ [class.union]p3: 1691 // An anonymous union shall not have private or protected 1692 // members (clause 11). 1693 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1694 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1695 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1696 Invalid = true; 1697 } 1698 } else if ((*Mem)->isImplicit()) { 1699 // Any implicit members are fine. 1700 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1701 // This is a type that showed up in an 1702 // elaborated-type-specifier inside the anonymous struct or 1703 // union, but which actually declares a type outside of the 1704 // anonymous struct or union. It's okay. 1705 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1706 if (!MemRecord->isAnonymousStructOrUnion() && 1707 MemRecord->getDeclName()) { 1708 // This is a nested type declaration. 1709 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1710 << (int)Record->isUnion(); 1711 Invalid = true; 1712 } 1713 } else { 1714 // We have something that isn't a non-static data 1715 // member. Complain about it. 1716 unsigned DK = diag::err_anonymous_record_bad_member; 1717 if (isa<TypeDecl>(*Mem)) 1718 DK = diag::err_anonymous_record_with_type; 1719 else if (isa<FunctionDecl>(*Mem)) 1720 DK = diag::err_anonymous_record_with_function; 1721 else if (isa<VarDecl>(*Mem)) 1722 DK = diag::err_anonymous_record_with_static; 1723 Diag((*Mem)->getLocation(), DK) 1724 << (int)Record->isUnion(); 1725 Invalid = true; 1726 } 1727 } 1728 } 1729 1730 if (!Record->isUnion() && !Owner->isRecord()) { 1731 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1732 << (int)getLangOptions().CPlusPlus; 1733 Invalid = true; 1734 } 1735 1736 // Mock up a declarator. 1737 Declarator Dc(DS, Declarator::TypeNameContext); 1738 TypeSourceInfo *TInfo = 0; 1739 GetTypeForDeclarator(Dc, S, &TInfo); 1740 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1741 1742 // Create a declaration for this anonymous struct/union. 1743 NamedDecl *Anon = 0; 1744 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1745 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1746 /*IdentifierInfo=*/0, 1747 Context.getTypeDeclType(Record), 1748 TInfo, 1749 /*BitWidth=*/0, /*Mutable=*/false); 1750 Anon->setAccess(AS_public); 1751 if (getLangOptions().CPlusPlus) 1752 FieldCollector->Add(cast<FieldDecl>(Anon)); 1753 } else { 1754 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1755 assert(SCSpec != DeclSpec::SCS_typedef && 1756 "Parser allowed 'typedef' as storage class VarDecl."); 1757 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1758 if (SCSpec == DeclSpec::SCS_mutable) { 1759 // mutable can only appear on non-static class members, so it's always 1760 // an error here 1761 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1762 Invalid = true; 1763 SC = VarDecl::None; 1764 } 1765 SCSpec = DS.getStorageClassSpecAsWritten(); 1766 VarDecl::StorageClass SCAsWritten 1767 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1768 1769 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1770 /*IdentifierInfo=*/0, 1771 Context.getTypeDeclType(Record), 1772 TInfo, SC, SCAsWritten); 1773 } 1774 Anon->setImplicit(); 1775 1776 // Add the anonymous struct/union object to the current 1777 // context. We'll be referencing this object when we refer to one of 1778 // its members. 1779 Owner->addDecl(Anon); 1780 1781 // Inject the members of the anonymous struct/union into the owning 1782 // context and into the identifier resolver chain for name lookup 1783 // purposes. 1784 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1785 Invalid = true; 1786 1787 // Mark this as an anonymous struct/union type. Note that we do not 1788 // do this until after we have already checked and injected the 1789 // members of this anonymous struct/union type, because otherwise 1790 // the members could be injected twice: once by DeclContext when it 1791 // builds its lookup table, and once by 1792 // InjectAnonymousStructOrUnionMembers. 1793 Record->setAnonymousStructOrUnion(true); 1794 1795 if (Invalid) 1796 Anon->setInvalidDecl(); 1797 1798 return DeclPtrTy::make(Anon); 1799} 1800 1801 1802/// GetNameForDeclarator - Determine the full declaration name for the 1803/// given Declarator. 1804DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1805 return GetNameFromUnqualifiedId(D.getName()); 1806} 1807 1808/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1809DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1810 switch (Name.getKind()) { 1811 case UnqualifiedId::IK_Identifier: 1812 return DeclarationName(Name.Identifier); 1813 1814 case UnqualifiedId::IK_OperatorFunctionId: 1815 return Context.DeclarationNames.getCXXOperatorName( 1816 Name.OperatorFunctionId.Operator); 1817 1818 case UnqualifiedId::IK_LiteralOperatorId: 1819 return Context.DeclarationNames.getCXXLiteralOperatorName( 1820 Name.Identifier); 1821 1822 case UnqualifiedId::IK_ConversionFunctionId: { 1823 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1824 if (Ty.isNull()) 1825 return DeclarationName(); 1826 1827 return Context.DeclarationNames.getCXXConversionFunctionName( 1828 Context.getCanonicalType(Ty)); 1829 } 1830 1831 case UnqualifiedId::IK_ConstructorName: { 1832 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1833 if (Ty.isNull()) 1834 return DeclarationName(); 1835 1836 return Context.DeclarationNames.getCXXConstructorName( 1837 Context.getCanonicalType(Ty)); 1838 } 1839 1840 case UnqualifiedId::IK_ConstructorTemplateId: { 1841 // In well-formed code, we can only have a constructor 1842 // template-id that refers to the current context, so go there 1843 // to find the actual type being constructed. 1844 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1845 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1846 return DeclarationName(); 1847 1848 // Determine the type of the class being constructed. 1849 QualType CurClassType = Context.getTypeDeclType(CurClass); 1850 1851 // FIXME: Check two things: that the template-id names the same type as 1852 // CurClassType, and that the template-id does not occur when the name 1853 // was qualified. 1854 1855 return Context.DeclarationNames.getCXXConstructorName( 1856 Context.getCanonicalType(CurClassType)); 1857 } 1858 1859 case UnqualifiedId::IK_DestructorName: { 1860 QualType Ty = GetTypeFromParser(Name.DestructorName); 1861 if (Ty.isNull()) 1862 return DeclarationName(); 1863 1864 return Context.DeclarationNames.getCXXDestructorName( 1865 Context.getCanonicalType(Ty)); 1866 } 1867 1868 case UnqualifiedId::IK_TemplateId: { 1869 TemplateName TName 1870 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1871 return Context.getNameForTemplate(TName); 1872 } 1873 } 1874 1875 assert(false && "Unknown name kind"); 1876 return DeclarationName(); 1877} 1878 1879/// isNearlyMatchingFunction - Determine whether the C++ functions 1880/// Declaration and Definition are "nearly" matching. This heuristic 1881/// is used to improve diagnostics in the case where an out-of-line 1882/// function definition doesn't match any declaration within 1883/// the class or namespace. 1884static bool isNearlyMatchingFunction(ASTContext &Context, 1885 FunctionDecl *Declaration, 1886 FunctionDecl *Definition) { 1887 if (Declaration->param_size() != Definition->param_size()) 1888 return false; 1889 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1890 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1891 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1892 1893 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1894 DefParamTy.getNonReferenceType())) 1895 return false; 1896 } 1897 1898 return true; 1899} 1900 1901Sema::DeclPtrTy 1902Sema::HandleDeclarator(Scope *S, Declarator &D, 1903 MultiTemplateParamsArg TemplateParamLists, 1904 bool IsFunctionDefinition) { 1905 DeclarationName Name = GetNameForDeclarator(D); 1906 1907 // All of these full declarators require an identifier. If it doesn't have 1908 // one, the ParsedFreeStandingDeclSpec action should be used. 1909 if (!Name) { 1910 if (!D.isInvalidType()) // Reject this if we think it is valid. 1911 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1912 diag::err_declarator_need_ident) 1913 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1914 return DeclPtrTy(); 1915 } 1916 1917 // The scope passed in may not be a decl scope. Zip up the scope tree until 1918 // we find one that is. 1919 while ((S->getFlags() & Scope::DeclScope) == 0 || 1920 (S->getFlags() & Scope::TemplateParamScope) != 0) 1921 S = S->getParent(); 1922 1923 // If this is an out-of-line definition of a member of a class template 1924 // or class template partial specialization, we may need to rebuild the 1925 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1926 // for more information. 1927 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1928 // handle expressions properly. 1929 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1930 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1931 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1932 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1933 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1934 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1935 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1936 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1937 // FIXME: Preserve type source info. 1938 QualType T = GetTypeFromParser(DS.getTypeRep()); 1939 1940 DeclContext *SavedContext = CurContext; 1941 CurContext = DC; 1942 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1943 CurContext = SavedContext; 1944 1945 if (T.isNull()) 1946 return DeclPtrTy(); 1947 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1948 } 1949 } 1950 1951 DeclContext *DC; 1952 NamedDecl *New; 1953 1954 TypeSourceInfo *TInfo = 0; 1955 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1956 1957 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1958 ForRedeclaration); 1959 1960 // See if this is a redefinition of a variable in the same scope. 1961 if (D.getCXXScopeSpec().isInvalid()) { 1962 DC = CurContext; 1963 D.setInvalidType(); 1964 } else if (!D.getCXXScopeSpec().isSet()) { 1965 bool IsLinkageLookup = false; 1966 1967 // If the declaration we're planning to build will be a function 1968 // or object with linkage, then look for another declaration with 1969 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1970 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1971 /* Do nothing*/; 1972 else if (R->isFunctionType()) { 1973 if (CurContext->isFunctionOrMethod() || 1974 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1975 IsLinkageLookup = true; 1976 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1977 IsLinkageLookup = true; 1978 else if (CurContext->getLookupContext()->isTranslationUnit() && 1979 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1980 IsLinkageLookup = true; 1981 1982 if (IsLinkageLookup) 1983 Previous.clear(LookupRedeclarationWithLinkage); 1984 1985 DC = CurContext; 1986 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1987 } else { // Something like "int foo::x;" 1988 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1989 1990 if (!DC) { 1991 // If we could not compute the declaration context, it's because the 1992 // declaration context is dependent but does not refer to a class, 1993 // class template, or class template partial specialization. Complain 1994 // and return early, to avoid the coming semantic disaster. 1995 Diag(D.getIdentifierLoc(), 1996 diag::err_template_qualified_declarator_no_match) 1997 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1998 << D.getCXXScopeSpec().getRange(); 1999 return DeclPtrTy(); 2000 } 2001 2002 if (!DC->isDependentContext() && 2003 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2004 return DeclPtrTy(); 2005 2006 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2007 Diag(D.getIdentifierLoc(), 2008 diag::err_member_def_undefined_record) 2009 << Name << DC << D.getCXXScopeSpec().getRange(); 2010 D.setInvalidType(); 2011 } 2012 2013 LookupQualifiedName(Previous, DC); 2014 2015 // Don't consider using declarations as previous declarations for 2016 // out-of-line members. 2017 RemoveUsingDecls(Previous); 2018 2019 // C++ 7.3.1.2p2: 2020 // Members (including explicit specializations of templates) of a named 2021 // namespace can also be defined outside that namespace by explicit 2022 // qualification of the name being defined, provided that the entity being 2023 // defined was already declared in the namespace and the definition appears 2024 // after the point of declaration in a namespace that encloses the 2025 // declarations namespace. 2026 // 2027 // Note that we only check the context at this point. We don't yet 2028 // have enough information to make sure that PrevDecl is actually 2029 // the declaration we want to match. For example, given: 2030 // 2031 // class X { 2032 // void f(); 2033 // void f(float); 2034 // }; 2035 // 2036 // void X::f(int) { } // ill-formed 2037 // 2038 // In this case, PrevDecl will point to the overload set 2039 // containing the two f's declared in X, but neither of them 2040 // matches. 2041 2042 // First check whether we named the global scope. 2043 if (isa<TranslationUnitDecl>(DC)) { 2044 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2045 << Name << D.getCXXScopeSpec().getRange(); 2046 } else { 2047 DeclContext *Cur = CurContext; 2048 while (isa<LinkageSpecDecl>(Cur)) 2049 Cur = Cur->getParent(); 2050 if (!Cur->Encloses(DC)) { 2051 // The qualifying scope doesn't enclose the original declaration. 2052 // Emit diagnostic based on current scope. 2053 SourceLocation L = D.getIdentifierLoc(); 2054 SourceRange R = D.getCXXScopeSpec().getRange(); 2055 if (isa<FunctionDecl>(Cur)) 2056 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2057 else 2058 Diag(L, diag::err_invalid_declarator_scope) 2059 << Name << cast<NamedDecl>(DC) << R; 2060 D.setInvalidType(); 2061 } 2062 } 2063 } 2064 2065 if (Previous.isSingleResult() && 2066 Previous.getFoundDecl()->isTemplateParameter()) { 2067 // Maybe we will complain about the shadowed template parameter. 2068 if (!D.isInvalidType()) 2069 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2070 Previous.getFoundDecl())) 2071 D.setInvalidType(); 2072 2073 // Just pretend that we didn't see the previous declaration. 2074 Previous.clear(); 2075 } 2076 2077 // In C++, the previous declaration we find might be a tag type 2078 // (class or enum). In this case, the new declaration will hide the 2079 // tag type. Note that this does does not apply if we're declaring a 2080 // typedef (C++ [dcl.typedef]p4). 2081 if (Previous.isSingleTagDecl() && 2082 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2083 Previous.clear(); 2084 2085 bool Redeclaration = false; 2086 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2087 if (TemplateParamLists.size()) { 2088 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2089 return DeclPtrTy(); 2090 } 2091 2092 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2093 } else if (R->isFunctionType()) { 2094 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2095 move(TemplateParamLists), 2096 IsFunctionDefinition, Redeclaration); 2097 } else { 2098 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2099 move(TemplateParamLists), 2100 Redeclaration); 2101 } 2102 2103 if (New == 0) 2104 return DeclPtrTy(); 2105 2106 // If this has an identifier and is not an invalid redeclaration or 2107 // function template specialization, add it to the scope stack. 2108 if (Name && !(Redeclaration && New->isInvalidDecl())) 2109 PushOnScopeChains(New, S); 2110 2111 return DeclPtrTy::make(New); 2112} 2113 2114/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2115/// types into constant array types in certain situations which would otherwise 2116/// be errors (for GCC compatibility). 2117static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2118 ASTContext &Context, 2119 bool &SizeIsNegative) { 2120 // This method tries to turn a variable array into a constant 2121 // array even when the size isn't an ICE. This is necessary 2122 // for compatibility with code that depends on gcc's buggy 2123 // constant expression folding, like struct {char x[(int)(char*)2];} 2124 SizeIsNegative = false; 2125 2126 QualifierCollector Qs; 2127 const Type *Ty = Qs.strip(T); 2128 2129 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2130 QualType Pointee = PTy->getPointeeType(); 2131 QualType FixedType = 2132 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2133 if (FixedType.isNull()) return FixedType; 2134 FixedType = Context.getPointerType(FixedType); 2135 return Qs.apply(FixedType); 2136 } 2137 2138 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2139 if (!VLATy) 2140 return QualType(); 2141 // FIXME: We should probably handle this case 2142 if (VLATy->getElementType()->isVariablyModifiedType()) 2143 return QualType(); 2144 2145 Expr::EvalResult EvalResult; 2146 if (!VLATy->getSizeExpr() || 2147 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2148 !EvalResult.Val.isInt()) 2149 return QualType(); 2150 2151 llvm::APSInt &Res = EvalResult.Val.getInt(); 2152 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2153 // TODO: preserve the size expression in declarator info 2154 return Context.getConstantArrayType(VLATy->getElementType(), 2155 Res, ArrayType::Normal, 0); 2156 } 2157 2158 SizeIsNegative = true; 2159 return QualType(); 2160} 2161 2162/// \brief Register the given locally-scoped external C declaration so 2163/// that it can be found later for redeclarations 2164void 2165Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2166 const LookupResult &Previous, 2167 Scope *S) { 2168 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2169 "Decl is not a locally-scoped decl!"); 2170 // Note that we have a locally-scoped external with this name. 2171 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2172 2173 if (!Previous.isSingleResult()) 2174 return; 2175 2176 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2177 2178 // If there was a previous declaration of this variable, it may be 2179 // in our identifier chain. Update the identifier chain with the new 2180 // declaration. 2181 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2182 // The previous declaration was found on the identifer resolver 2183 // chain, so remove it from its scope. 2184 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2185 S = S->getParent(); 2186 2187 if (S) 2188 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2189 } 2190} 2191 2192/// \brief Diagnose function specifiers on a declaration of an identifier that 2193/// does not identify a function. 2194void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2195 // FIXME: We should probably indicate the identifier in question to avoid 2196 // confusion for constructs like "inline int a(), b;" 2197 if (D.getDeclSpec().isInlineSpecified()) 2198 Diag(D.getDeclSpec().getInlineSpecLoc(), 2199 diag::err_inline_non_function); 2200 2201 if (D.getDeclSpec().isVirtualSpecified()) 2202 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2203 diag::err_virtual_non_function); 2204 2205 if (D.getDeclSpec().isExplicitSpecified()) 2206 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2207 diag::err_explicit_non_function); 2208} 2209 2210NamedDecl* 2211Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2212 QualType R, TypeSourceInfo *TInfo, 2213 LookupResult &Previous, bool &Redeclaration) { 2214 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2215 if (D.getCXXScopeSpec().isSet()) { 2216 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2217 << D.getCXXScopeSpec().getRange(); 2218 D.setInvalidType(); 2219 // Pretend we didn't see the scope specifier. 2220 DC = CurContext; 2221 Previous.clear(); 2222 } 2223 2224 if (getLangOptions().CPlusPlus) { 2225 // Check that there are no default arguments (C++ only). 2226 CheckExtraCXXDefaultArguments(D); 2227 } 2228 2229 DiagnoseFunctionSpecifiers(D); 2230 2231 if (D.getDeclSpec().isThreadSpecified()) 2232 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2233 2234 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2235 if (!NewTD) return 0; 2236 2237 // Handle attributes prior to checking for duplicates in MergeVarDecl 2238 ProcessDeclAttributes(S, NewTD, D); 2239 2240 // Merge the decl with the existing one if appropriate. If the decl is 2241 // in an outer scope, it isn't the same thing. 2242 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2243 if (!Previous.empty()) { 2244 Redeclaration = true; 2245 MergeTypeDefDecl(NewTD, Previous); 2246 } 2247 2248 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2249 // then it shall have block scope. 2250 QualType T = NewTD->getUnderlyingType(); 2251 if (T->isVariablyModifiedType()) { 2252 FunctionNeedsScopeChecking() = true; 2253 2254 if (S->getFnParent() == 0) { 2255 bool SizeIsNegative; 2256 QualType FixedTy = 2257 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2258 if (!FixedTy.isNull()) { 2259 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2260 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2261 } else { 2262 if (SizeIsNegative) 2263 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2264 else if (T->isVariableArrayType()) 2265 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2266 else 2267 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2268 NewTD->setInvalidDecl(); 2269 } 2270 } 2271 } 2272 2273 // If this is the C FILE type, notify the AST context. 2274 if (IdentifierInfo *II = NewTD->getIdentifier()) 2275 if (!NewTD->isInvalidDecl() && 2276 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2277 if (II->isStr("FILE")) 2278 Context.setFILEDecl(NewTD); 2279 else if (II->isStr("jmp_buf")) 2280 Context.setjmp_bufDecl(NewTD); 2281 else if (II->isStr("sigjmp_buf")) 2282 Context.setsigjmp_bufDecl(NewTD); 2283 } 2284 2285 return NewTD; 2286} 2287 2288/// \brief Determines whether the given declaration is an out-of-scope 2289/// previous declaration. 2290/// 2291/// This routine should be invoked when name lookup has found a 2292/// previous declaration (PrevDecl) that is not in the scope where a 2293/// new declaration by the same name is being introduced. If the new 2294/// declaration occurs in a local scope, previous declarations with 2295/// linkage may still be considered previous declarations (C99 2296/// 6.2.2p4-5, C++ [basic.link]p6). 2297/// 2298/// \param PrevDecl the previous declaration found by name 2299/// lookup 2300/// 2301/// \param DC the context in which the new declaration is being 2302/// declared. 2303/// 2304/// \returns true if PrevDecl is an out-of-scope previous declaration 2305/// for a new delcaration with the same name. 2306static bool 2307isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2308 ASTContext &Context) { 2309 if (!PrevDecl) 2310 return 0; 2311 2312 if (!PrevDecl->hasLinkage()) 2313 return false; 2314 2315 if (Context.getLangOptions().CPlusPlus) { 2316 // C++ [basic.link]p6: 2317 // If there is a visible declaration of an entity with linkage 2318 // having the same name and type, ignoring entities declared 2319 // outside the innermost enclosing namespace scope, the block 2320 // scope declaration declares that same entity and receives the 2321 // linkage of the previous declaration. 2322 DeclContext *OuterContext = DC->getLookupContext(); 2323 if (!OuterContext->isFunctionOrMethod()) 2324 // This rule only applies to block-scope declarations. 2325 return false; 2326 else { 2327 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2328 if (PrevOuterContext->isRecord()) 2329 // We found a member function: ignore it. 2330 return false; 2331 else { 2332 // Find the innermost enclosing namespace for the new and 2333 // previous declarations. 2334 while (!OuterContext->isFileContext()) 2335 OuterContext = OuterContext->getParent(); 2336 while (!PrevOuterContext->isFileContext()) 2337 PrevOuterContext = PrevOuterContext->getParent(); 2338 2339 // The previous declaration is in a different namespace, so it 2340 // isn't the same function. 2341 if (OuterContext->getPrimaryContext() != 2342 PrevOuterContext->getPrimaryContext()) 2343 return false; 2344 } 2345 } 2346 } 2347 2348 return true; 2349} 2350 2351static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2352 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2353 if (!SS.isSet()) return; 2354 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2355 SS.getRange()); 2356} 2357 2358NamedDecl* 2359Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2360 QualType R, TypeSourceInfo *TInfo, 2361 LookupResult &Previous, 2362 MultiTemplateParamsArg TemplateParamLists, 2363 bool &Redeclaration) { 2364 DeclarationName Name = GetNameForDeclarator(D); 2365 2366 // Check that there are no default arguments (C++ only). 2367 if (getLangOptions().CPlusPlus) 2368 CheckExtraCXXDefaultArguments(D); 2369 2370 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2371 assert(SCSpec != DeclSpec::SCS_typedef && 2372 "Parser allowed 'typedef' as storage class VarDecl."); 2373 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2374 if (SCSpec == DeclSpec::SCS_mutable) { 2375 // mutable can only appear on non-static class members, so it's always 2376 // an error here 2377 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2378 D.setInvalidType(); 2379 SC = VarDecl::None; 2380 } 2381 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2382 VarDecl::StorageClass SCAsWritten 2383 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2384 2385 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2386 if (!II) { 2387 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2388 << Name.getAsString(); 2389 return 0; 2390 } 2391 2392 DiagnoseFunctionSpecifiers(D); 2393 2394 if (!DC->isRecord() && S->getFnParent() == 0) { 2395 // C99 6.9p2: The storage-class specifiers auto and register shall not 2396 // appear in the declaration specifiers in an external declaration. 2397 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2398 2399 // If this is a register variable with an asm label specified, then this 2400 // is a GNU extension. 2401 if (SC == VarDecl::Register && D.getAsmLabel()) 2402 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2403 else 2404 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2405 D.setInvalidType(); 2406 } 2407 } 2408 if (DC->isRecord() && !CurContext->isRecord()) { 2409 // This is an out-of-line definition of a static data member. 2410 if (SC == VarDecl::Static) { 2411 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2412 diag::err_static_out_of_line) 2413 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2414 } else if (SC == VarDecl::None) 2415 SC = VarDecl::Static; 2416 } 2417 if (SC == VarDecl::Static) { 2418 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2419 if (RD->isLocalClass()) 2420 Diag(D.getIdentifierLoc(), 2421 diag::err_static_data_member_not_allowed_in_local_class) 2422 << Name << RD->getDeclName(); 2423 } 2424 } 2425 2426 // Match up the template parameter lists with the scope specifier, then 2427 // determine whether we have a template or a template specialization. 2428 bool isExplicitSpecialization = false; 2429 if (TemplateParameterList *TemplateParams 2430 = MatchTemplateParametersToScopeSpecifier( 2431 D.getDeclSpec().getSourceRange().getBegin(), 2432 D.getCXXScopeSpec(), 2433 (TemplateParameterList**)TemplateParamLists.get(), 2434 TemplateParamLists.size(), 2435 /*never a friend*/ false, 2436 isExplicitSpecialization)) { 2437 if (TemplateParams->size() > 0) { 2438 // There is no such thing as a variable template. 2439 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2440 << II 2441 << SourceRange(TemplateParams->getTemplateLoc(), 2442 TemplateParams->getRAngleLoc()); 2443 return 0; 2444 } else { 2445 // There is an extraneous 'template<>' for this variable. Complain 2446 // about it, but allow the declaration of the variable. 2447 Diag(TemplateParams->getTemplateLoc(), 2448 diag::err_template_variable_noparams) 2449 << II 2450 << SourceRange(TemplateParams->getTemplateLoc(), 2451 TemplateParams->getRAngleLoc()); 2452 2453 isExplicitSpecialization = true; 2454 } 2455 } 2456 2457 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2458 II, R, TInfo, SC, SCAsWritten); 2459 2460 if (D.isInvalidType()) 2461 NewVD->setInvalidDecl(); 2462 2463 SetNestedNameSpecifier(NewVD, D); 2464 2465 if (D.getDeclSpec().isThreadSpecified()) { 2466 if (NewVD->hasLocalStorage()) 2467 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2468 else if (!Context.Target.isTLSSupported()) 2469 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2470 else 2471 NewVD->setThreadSpecified(true); 2472 } 2473 2474 // Set the lexical context. If the declarator has a C++ scope specifier, the 2475 // lexical context will be different from the semantic context. 2476 NewVD->setLexicalDeclContext(CurContext); 2477 2478 // Handle attributes prior to checking for duplicates in MergeVarDecl 2479 ProcessDeclAttributes(S, NewVD, D); 2480 2481 // Handle GNU asm-label extension (encoded as an attribute). 2482 if (Expr *E = (Expr*) D.getAsmLabel()) { 2483 // The parser guarantees this is a string. 2484 StringLiteral *SE = cast<StringLiteral>(E); 2485 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2486 } 2487 2488 // Diagnose shadowed variables before filtering for scope. 2489 if (!D.getCXXScopeSpec().isSet()) 2490 CheckShadow(S, NewVD, Previous); 2491 2492 // Don't consider existing declarations that are in a different 2493 // scope and are out-of-semantic-context declarations (if the new 2494 // declaration has linkage). 2495 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2496 2497 // Merge the decl with the existing one if appropriate. 2498 if (!Previous.empty()) { 2499 if (Previous.isSingleResult() && 2500 isa<FieldDecl>(Previous.getFoundDecl()) && 2501 D.getCXXScopeSpec().isSet()) { 2502 // The user tried to define a non-static data member 2503 // out-of-line (C++ [dcl.meaning]p1). 2504 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2505 << D.getCXXScopeSpec().getRange(); 2506 Previous.clear(); 2507 NewVD->setInvalidDecl(); 2508 } 2509 } else if (D.getCXXScopeSpec().isSet()) { 2510 // No previous declaration in the qualifying scope. 2511 Diag(D.getIdentifierLoc(), diag::err_no_member) 2512 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2513 << D.getCXXScopeSpec().getRange(); 2514 NewVD->setInvalidDecl(); 2515 } 2516 2517 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2518 2519 // This is an explicit specialization of a static data member. Check it. 2520 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2521 CheckMemberSpecialization(NewVD, Previous)) 2522 NewVD->setInvalidDecl(); 2523 2524 // attributes declared post-definition are currently ignored 2525 if (Previous.isSingleResult()) { 2526 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2527 if (Def && (Def = Def->getDefinition()) && 2528 Def != NewVD && D.hasAttributes()) { 2529 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2530 Diag(Def->getLocation(), diag::note_previous_definition); 2531 } 2532 } 2533 2534 // If this is a locally-scoped extern C variable, update the map of 2535 // such variables. 2536 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2537 !NewVD->isInvalidDecl()) 2538 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2539 2540 return NewVD; 2541} 2542 2543/// \brief Diagnose variable or built-in function shadowing. Implements 2544/// -Wshadow. 2545/// 2546/// This method is called whenever a VarDecl is added to a "useful" 2547/// scope. 2548/// 2549/// \param S the scope in which the shadowing name is being declared 2550/// \param R the lookup of the name 2551/// 2552void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2553 // Return if warning is ignored. 2554 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2555 return; 2556 2557 // Don't diagnose declarations at file scope. The scope might not 2558 // have a DeclContext if (e.g.) we're parsing a function prototype. 2559 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2560 if (NewDC && NewDC->isFileContext()) 2561 return; 2562 2563 // Only diagnose if we're shadowing an unambiguous field or variable. 2564 if (R.getResultKind() != LookupResult::Found) 2565 return; 2566 2567 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2568 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2569 return; 2570 2571 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2572 2573 // Only warn about certain kinds of shadowing for class members. 2574 if (NewDC && NewDC->isRecord()) { 2575 // In particular, don't warn about shadowing non-class members. 2576 if (!OldDC->isRecord()) 2577 return; 2578 2579 // TODO: should we warn about static data members shadowing 2580 // static data members from base classes? 2581 2582 // TODO: don't diagnose for inaccessible shadowed members. 2583 // This is hard to do perfectly because we might friend the 2584 // shadowing context, but that's just a false negative. 2585 } 2586 2587 // Determine what kind of declaration we're shadowing. 2588 unsigned Kind; 2589 if (isa<RecordDecl>(OldDC)) { 2590 if (isa<FieldDecl>(ShadowedDecl)) 2591 Kind = 3; // field 2592 else 2593 Kind = 2; // static data member 2594 } else if (OldDC->isFileContext()) 2595 Kind = 1; // global 2596 else 2597 Kind = 0; // local 2598 2599 DeclarationName Name = R.getLookupName(); 2600 2601 // Emit warning and note. 2602 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2603 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2604} 2605 2606/// \brief Check -Wshadow without the advantage of a previous lookup. 2607void Sema::CheckShadow(Scope *S, VarDecl *D) { 2608 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2609 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2610 LookupName(R, S); 2611 CheckShadow(S, D, R); 2612} 2613 2614/// \brief Perform semantic checking on a newly-created variable 2615/// declaration. 2616/// 2617/// This routine performs all of the type-checking required for a 2618/// variable declaration once it has been built. It is used both to 2619/// check variables after they have been parsed and their declarators 2620/// have been translated into a declaration, and to check variables 2621/// that have been instantiated from a template. 2622/// 2623/// Sets NewVD->isInvalidDecl() if an error was encountered. 2624void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2625 LookupResult &Previous, 2626 bool &Redeclaration) { 2627 // If the decl is already known invalid, don't check it. 2628 if (NewVD->isInvalidDecl()) 2629 return; 2630 2631 QualType T = NewVD->getType(); 2632 2633 if (T->isObjCInterfaceType()) { 2634 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2635 return NewVD->setInvalidDecl(); 2636 } 2637 2638 // Emit an error if an address space was applied to decl with local storage. 2639 // This includes arrays of objects with address space qualifiers, but not 2640 // automatic variables that point to other address spaces. 2641 // ISO/IEC TR 18037 S5.1.2 2642 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2643 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2644 return NewVD->setInvalidDecl(); 2645 } 2646 2647 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2648 && !NewVD->hasAttr<BlocksAttr>()) 2649 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2650 2651 bool isVM = T->isVariablyModifiedType(); 2652 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2653 NewVD->hasAttr<BlocksAttr>() || 2654 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2655 // However, this turns on the scope checker for everything with a variable 2656 // which may impact compile time. See if we can find a better solution 2657 // to this, perhaps only checking functions that contain gotos in C++? 2658 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2659 FunctionNeedsScopeChecking() = true; 2660 2661 if ((isVM && NewVD->hasLinkage()) || 2662 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2663 bool SizeIsNegative; 2664 QualType FixedTy = 2665 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2666 2667 if (FixedTy.isNull() && T->isVariableArrayType()) { 2668 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2669 // FIXME: This won't give the correct result for 2670 // int a[10][n]; 2671 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2672 2673 if (NewVD->isFileVarDecl()) 2674 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2675 << SizeRange; 2676 else if (NewVD->getStorageClass() == VarDecl::Static) 2677 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2678 << SizeRange; 2679 else 2680 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2681 << SizeRange; 2682 return NewVD->setInvalidDecl(); 2683 } 2684 2685 if (FixedTy.isNull()) { 2686 if (NewVD->isFileVarDecl()) 2687 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2688 else 2689 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2690 return NewVD->setInvalidDecl(); 2691 } 2692 2693 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2694 NewVD->setType(FixedTy); 2695 } 2696 2697 if (Previous.empty() && NewVD->isExternC()) { 2698 // Since we did not find anything by this name and we're declaring 2699 // an extern "C" variable, look for a non-visible extern "C" 2700 // declaration with the same name. 2701 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2702 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2703 if (Pos != LocallyScopedExternalDecls.end()) 2704 Previous.addDecl(Pos->second); 2705 } 2706 2707 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2708 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2709 << T; 2710 return NewVD->setInvalidDecl(); 2711 } 2712 2713 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2714 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2715 return NewVD->setInvalidDecl(); 2716 } 2717 2718 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2719 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2720 return NewVD->setInvalidDecl(); 2721 } 2722 2723 if (!Previous.empty()) { 2724 Redeclaration = true; 2725 MergeVarDecl(NewVD, Previous); 2726 } 2727} 2728 2729/// \brief Data used with FindOverriddenMethod 2730struct FindOverriddenMethodData { 2731 Sema *S; 2732 CXXMethodDecl *Method; 2733}; 2734 2735/// \brief Member lookup function that determines whether a given C++ 2736/// method overrides a method in a base class, to be used with 2737/// CXXRecordDecl::lookupInBases(). 2738static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2739 CXXBasePath &Path, 2740 void *UserData) { 2741 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2742 2743 FindOverriddenMethodData *Data 2744 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2745 2746 DeclarationName Name = Data->Method->getDeclName(); 2747 2748 // FIXME: Do we care about other names here too? 2749 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2750 // We really want to find the base class constructor here. 2751 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2752 CanQualType CT = Data->S->Context.getCanonicalType(T); 2753 2754 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2755 } 2756 2757 for (Path.Decls = BaseRecord->lookup(Name); 2758 Path.Decls.first != Path.Decls.second; 2759 ++Path.Decls.first) { 2760 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2761 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2762 return true; 2763 } 2764 } 2765 2766 return false; 2767} 2768 2769/// AddOverriddenMethods - See if a method overrides any in the base classes, 2770/// and if so, check that it's a valid override and remember it. 2771void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2772 // Look for virtual methods in base classes that this method might override. 2773 CXXBasePaths Paths; 2774 FindOverriddenMethodData Data; 2775 Data.Method = MD; 2776 Data.S = this; 2777 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2778 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2779 E = Paths.found_decls_end(); I != E; ++I) { 2780 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2781 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2782 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2783 !CheckOverridingFunctionAttributes(MD, OldMD)) 2784 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2785 } 2786 } 2787 } 2788} 2789 2790NamedDecl* 2791Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2792 QualType R, TypeSourceInfo *TInfo, 2793 LookupResult &Previous, 2794 MultiTemplateParamsArg TemplateParamLists, 2795 bool IsFunctionDefinition, bool &Redeclaration) { 2796 assert(R.getTypePtr()->isFunctionType()); 2797 2798 DeclarationName Name = GetNameForDeclarator(D); 2799 FunctionDecl::StorageClass SC = FunctionDecl::None; 2800 switch (D.getDeclSpec().getStorageClassSpec()) { 2801 default: assert(0 && "Unknown storage class!"); 2802 case DeclSpec::SCS_auto: 2803 case DeclSpec::SCS_register: 2804 case DeclSpec::SCS_mutable: 2805 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2806 diag::err_typecheck_sclass_func); 2807 D.setInvalidType(); 2808 break; 2809 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2810 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2811 case DeclSpec::SCS_static: { 2812 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2813 // C99 6.7.1p5: 2814 // The declaration of an identifier for a function that has 2815 // block scope shall have no explicit storage-class specifier 2816 // other than extern 2817 // See also (C++ [dcl.stc]p4). 2818 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2819 diag::err_static_block_func); 2820 SC = FunctionDecl::None; 2821 } else 2822 SC = FunctionDecl::Static; 2823 break; 2824 } 2825 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2826 } 2827 2828 if (D.getDeclSpec().isThreadSpecified()) 2829 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2830 2831 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2832 bool isInline = D.getDeclSpec().isInlineSpecified(); 2833 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2834 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2835 2836 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2837 FunctionDecl::StorageClass SCAsWritten 2838 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 2839 2840 // Check that the return type is not an abstract class type. 2841 // For record types, this is done by the AbstractClassUsageDiagnoser once 2842 // the class has been completely parsed. 2843 if (!DC->isRecord() && 2844 RequireNonAbstractType(D.getIdentifierLoc(), 2845 R->getAs<FunctionType>()->getResultType(), 2846 diag::err_abstract_type_in_decl, 2847 AbstractReturnType)) 2848 D.setInvalidType(); 2849 2850 // Do not allow returning a objc interface by-value. 2851 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2852 Diag(D.getIdentifierLoc(), 2853 diag::err_object_cannot_be_passed_returned_by_value) << 0 2854 << R->getAs<FunctionType>()->getResultType(); 2855 D.setInvalidType(); 2856 } 2857 2858 bool isVirtualOkay = false; 2859 FunctionDecl *NewFD; 2860 2861 if (isFriend) { 2862 // C++ [class.friend]p5 2863 // A function can be defined in a friend declaration of a 2864 // class . . . . Such a function is implicitly inline. 2865 isInline |= IsFunctionDefinition; 2866 } 2867 2868 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2869 // This is a C++ constructor declaration. 2870 assert(DC->isRecord() && 2871 "Constructors can only be declared in a member context"); 2872 2873 R = CheckConstructorDeclarator(D, R, SC); 2874 2875 // Create the new declaration 2876 NewFD = CXXConstructorDecl::Create(Context, 2877 cast<CXXRecordDecl>(DC), 2878 D.getIdentifierLoc(), Name, R, TInfo, 2879 isExplicit, isInline, 2880 /*isImplicitlyDeclared=*/false); 2881 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2882 // This is a C++ destructor declaration. 2883 if (DC->isRecord()) { 2884 R = CheckDestructorDeclarator(D, SC); 2885 2886 NewFD = CXXDestructorDecl::Create(Context, 2887 cast<CXXRecordDecl>(DC), 2888 D.getIdentifierLoc(), Name, R, 2889 isInline, 2890 /*isImplicitlyDeclared=*/false); 2891 NewFD->setTypeSourceInfo(TInfo); 2892 2893 isVirtualOkay = true; 2894 } else { 2895 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2896 2897 // Create a FunctionDecl to satisfy the function definition parsing 2898 // code path. 2899 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2900 Name, R, TInfo, SC, SCAsWritten, isInline, 2901 /*hasPrototype=*/true); 2902 D.setInvalidType(); 2903 } 2904 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2905 if (!DC->isRecord()) { 2906 Diag(D.getIdentifierLoc(), 2907 diag::err_conv_function_not_member); 2908 return 0; 2909 } 2910 2911 CheckConversionDeclarator(D, R, SC); 2912 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2913 D.getIdentifierLoc(), Name, R, TInfo, 2914 isInline, isExplicit); 2915 2916 isVirtualOkay = true; 2917 } else if (DC->isRecord()) { 2918 // If the of the function is the same as the name of the record, then this 2919 // must be an invalid constructor that has a return type. 2920 // (The parser checks for a return type and makes the declarator a 2921 // constructor if it has no return type). 2922 // must have an invalid constructor that has a return type 2923 if (Name.getAsIdentifierInfo() && 2924 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2925 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2926 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2927 << SourceRange(D.getIdentifierLoc()); 2928 return 0; 2929 } 2930 2931 bool isStatic = SC == FunctionDecl::Static; 2932 2933 // [class.free]p1: 2934 // Any allocation function for a class T is a static member 2935 // (even if not explicitly declared static). 2936 if (Name.getCXXOverloadedOperator() == OO_New || 2937 Name.getCXXOverloadedOperator() == OO_Array_New) 2938 isStatic = true; 2939 2940 // [class.free]p6 Any deallocation function for a class X is a static member 2941 // (even if not explicitly declared static). 2942 if (Name.getCXXOverloadedOperator() == OO_Delete || 2943 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2944 isStatic = true; 2945 2946 // This is a C++ method declaration. 2947 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2948 D.getIdentifierLoc(), Name, R, TInfo, 2949 isStatic, SCAsWritten, isInline); 2950 2951 isVirtualOkay = !isStatic; 2952 } else { 2953 // Determine whether the function was written with a 2954 // prototype. This true when: 2955 // - we're in C++ (where every function has a prototype), 2956 // - there is a prototype in the declarator, or 2957 // - the type R of the function is some kind of typedef or other reference 2958 // to a type name (which eventually refers to a function type). 2959 bool HasPrototype = 2960 getLangOptions().CPlusPlus || 2961 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2962 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2963 2964 NewFD = FunctionDecl::Create(Context, DC, 2965 D.getIdentifierLoc(), 2966 Name, R, TInfo, SC, SCAsWritten, isInline, 2967 HasPrototype); 2968 } 2969 2970 if (D.isInvalidType()) 2971 NewFD->setInvalidDecl(); 2972 2973 SetNestedNameSpecifier(NewFD, D); 2974 2975 // Set the lexical context. If the declarator has a C++ 2976 // scope specifier, or is the object of a friend declaration, the 2977 // lexical context will be different from the semantic context. 2978 NewFD->setLexicalDeclContext(CurContext); 2979 2980 // Match up the template parameter lists with the scope specifier, then 2981 // determine whether we have a template or a template specialization. 2982 FunctionTemplateDecl *FunctionTemplate = 0; 2983 bool isExplicitSpecialization = false; 2984 bool isFunctionTemplateSpecialization = false; 2985 if (TemplateParameterList *TemplateParams 2986 = MatchTemplateParametersToScopeSpecifier( 2987 D.getDeclSpec().getSourceRange().getBegin(), 2988 D.getCXXScopeSpec(), 2989 (TemplateParameterList**)TemplateParamLists.get(), 2990 TemplateParamLists.size(), 2991 isFriend, 2992 isExplicitSpecialization)) { 2993 if (TemplateParams->size() > 0) { 2994 // This is a function template 2995 2996 // Check that we can declare a template here. 2997 if (CheckTemplateDeclScope(S, TemplateParams)) 2998 return 0; 2999 3000 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3001 NewFD->getLocation(), 3002 Name, TemplateParams, 3003 NewFD); 3004 FunctionTemplate->setLexicalDeclContext(CurContext); 3005 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3006 } else { 3007 // This is a function template specialization. 3008 isFunctionTemplateSpecialization = true; 3009 3010 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3011 if (isFriend && isFunctionTemplateSpecialization) { 3012 // We want to remove the "template<>", found here. 3013 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3014 3015 // If we remove the template<> and the name is not a 3016 // template-id, we're actually silently creating a problem: 3017 // the friend declaration will refer to an untemplated decl, 3018 // and clearly the user wants a template specialization. So 3019 // we need to insert '<>' after the name. 3020 SourceLocation InsertLoc; 3021 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3022 InsertLoc = D.getName().getSourceRange().getEnd(); 3023 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3024 } 3025 3026 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3027 << Name << RemoveRange 3028 << FixItHint::CreateRemoval(RemoveRange) 3029 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3030 } 3031 } 3032 3033 // FIXME: Free this memory properly. 3034 TemplateParamLists.release(); 3035 } 3036 3037 // C++ [dcl.fct.spec]p5: 3038 // The virtual specifier shall only be used in declarations of 3039 // nonstatic class member functions that appear within a 3040 // member-specification of a class declaration; see 10.3. 3041 // 3042 if (isVirtual && !NewFD->isInvalidDecl()) { 3043 if (!isVirtualOkay) { 3044 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3045 diag::err_virtual_non_function); 3046 } else if (!CurContext->isRecord()) { 3047 // 'virtual' was specified outside of the class. 3048 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3049 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3050 } else { 3051 // Okay: Add virtual to the method. 3052 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3053 CurClass->setMethodAsVirtual(NewFD); 3054 } 3055 } 3056 3057 // C++ [dcl.fct.spec]p6: 3058 // The explicit specifier shall be used only in the declaration of a 3059 // constructor or conversion function within its class definition; see 12.3.1 3060 // and 12.3.2. 3061 if (isExplicit && !NewFD->isInvalidDecl()) { 3062 if (!CurContext->isRecord()) { 3063 // 'explicit' was specified outside of the class. 3064 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3065 diag::err_explicit_out_of_class) 3066 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3067 } else if (!isa<CXXConstructorDecl>(NewFD) && 3068 !isa<CXXConversionDecl>(NewFD)) { 3069 // 'explicit' was specified on a function that wasn't a constructor 3070 // or conversion function. 3071 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3072 diag::err_explicit_non_ctor_or_conv_function) 3073 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3074 } 3075 } 3076 3077 // Filter out previous declarations that don't match the scope. 3078 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3079 3080 if (isFriend) { 3081 // DC is the namespace in which the function is being declared. 3082 assert((DC->isFileContext() || !Previous.empty()) && 3083 "previously-undeclared friend function being created " 3084 "in a non-namespace context"); 3085 3086 // For now, claim that the objects have no previous declaration. 3087 if (FunctionTemplate) { 3088 FunctionTemplate->setObjectOfFriendDecl(false); 3089 FunctionTemplate->setAccess(AS_public); 3090 } 3091 NewFD->setObjectOfFriendDecl(false); 3092 NewFD->setAccess(AS_public); 3093 } 3094 3095 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3096 !CurContext->isRecord()) { 3097 // C++ [class.static]p1: 3098 // A data or function member of a class may be declared static 3099 // in a class definition, in which case it is a static member of 3100 // the class. 3101 3102 // Complain about the 'static' specifier if it's on an out-of-line 3103 // member function definition. 3104 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3105 diag::err_static_out_of_line) 3106 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3107 } 3108 3109 // Handle GNU asm-label extension (encoded as an attribute). 3110 if (Expr *E = (Expr*) D.getAsmLabel()) { 3111 // The parser guarantees this is a string. 3112 StringLiteral *SE = cast<StringLiteral>(E); 3113 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3114 } 3115 3116 // Copy the parameter declarations from the declarator D to the function 3117 // declaration NewFD, if they are available. First scavenge them into Params. 3118 llvm::SmallVector<ParmVarDecl*, 16> Params; 3119 if (D.getNumTypeObjects() > 0) { 3120 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3121 3122 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3123 // function that takes no arguments, not a function that takes a 3124 // single void argument. 3125 // We let through "const void" here because Sema::GetTypeForDeclarator 3126 // already checks for that case. 3127 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3128 FTI.ArgInfo[0].Param && 3129 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3130 // Empty arg list, don't push any params. 3131 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3132 3133 // In C++, the empty parameter-type-list must be spelled "void"; a 3134 // typedef of void is not permitted. 3135 if (getLangOptions().CPlusPlus && 3136 Param->getType().getUnqualifiedType() != Context.VoidTy) 3137 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3138 // FIXME: Leaks decl? 3139 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3140 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3141 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3142 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3143 Param->setDeclContext(NewFD); 3144 Params.push_back(Param); 3145 3146 if (Param->isInvalidDecl()) 3147 NewFD->setInvalidDecl(); 3148 } 3149 } 3150 3151 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3152 // When we're declaring a function with a typedef, typeof, etc as in the 3153 // following example, we'll need to synthesize (unnamed) 3154 // parameters for use in the declaration. 3155 // 3156 // @code 3157 // typedef void fn(int); 3158 // fn f; 3159 // @endcode 3160 3161 // Synthesize a parameter for each argument type. 3162 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3163 AE = FT->arg_type_end(); AI != AE; ++AI) { 3164 ParmVarDecl *Param = ParmVarDecl::Create(Context, NewFD, 3165 SourceLocation(), 0, 3166 *AI, /*TInfo=*/0, 3167 VarDecl::None, 3168 VarDecl::None, 0); 3169 Param->setImplicit(); 3170 Params.push_back(Param); 3171 } 3172 } else { 3173 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3174 "Should not need args for typedef of non-prototype fn"); 3175 } 3176 // Finally, we know we have the right number of parameters, install them. 3177 NewFD->setParams(Params.data(), Params.size()); 3178 3179 // If the declarator is a template-id, translate the parser's template 3180 // argument list into our AST format. 3181 bool HasExplicitTemplateArgs = false; 3182 TemplateArgumentListInfo TemplateArgs; 3183 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3184 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3185 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3186 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3187 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3188 TemplateId->getTemplateArgs(), 3189 TemplateId->NumArgs); 3190 translateTemplateArguments(TemplateArgsPtr, 3191 TemplateArgs); 3192 TemplateArgsPtr.release(); 3193 3194 HasExplicitTemplateArgs = true; 3195 3196 if (FunctionTemplate) { 3197 // FIXME: Diagnose function template with explicit template 3198 // arguments. 3199 HasExplicitTemplateArgs = false; 3200 } else if (!isFunctionTemplateSpecialization && 3201 !D.getDeclSpec().isFriendSpecified()) { 3202 // We have encountered something that the user meant to be a 3203 // specialization (because it has explicitly-specified template 3204 // arguments) but that was not introduced with a "template<>" (or had 3205 // too few of them). 3206 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3207 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3208 << FixItHint::CreateInsertion( 3209 D.getDeclSpec().getSourceRange().getBegin(), 3210 "template<> "); 3211 isFunctionTemplateSpecialization = true; 3212 } else { 3213 // "friend void foo<>(int);" is an implicit specialization decl. 3214 isFunctionTemplateSpecialization = true; 3215 } 3216 } else if (isFriend && isFunctionTemplateSpecialization) { 3217 // This combination is only possible in a recovery case; the user 3218 // wrote something like: 3219 // template <> friend void foo(int); 3220 // which we're recovering from as if the user had written: 3221 // friend void foo<>(int); 3222 // Go ahead and fake up a template id. 3223 HasExplicitTemplateArgs = true; 3224 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3225 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3226 } 3227 3228 // If it's a friend (and only if it's a friend), it's possible 3229 // that either the specialized function type or the specialized 3230 // template is dependent, and therefore matching will fail. In 3231 // this case, don't check the specialization yet. 3232 if (isFunctionTemplateSpecialization && isFriend && 3233 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3234 assert(HasExplicitTemplateArgs && 3235 "friend function specialization without template args"); 3236 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3237 Previous)) 3238 NewFD->setInvalidDecl(); 3239 } else if (isFunctionTemplateSpecialization) { 3240 if (CheckFunctionTemplateSpecialization(NewFD, 3241 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3242 Previous)) 3243 NewFD->setInvalidDecl(); 3244 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3245 if (CheckMemberSpecialization(NewFD, Previous)) 3246 NewFD->setInvalidDecl(); 3247 } 3248 3249 // Perform semantic checking on the function declaration. 3250 bool OverloadableAttrRequired = false; // FIXME: HACK! 3251 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3252 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3253 3254 assert((NewFD->isInvalidDecl() || !Redeclaration || 3255 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3256 "previous declaration set still overloaded"); 3257 3258 if (isFriend && Redeclaration) { 3259 AccessSpecifier Access = AS_public; 3260 if (!NewFD->isInvalidDecl()) 3261 Access = NewFD->getPreviousDeclaration()->getAccess(); 3262 3263 if (FunctionTemplate) { 3264 FunctionTemplate->setObjectOfFriendDecl(true); 3265 FunctionTemplate->setAccess(Access); 3266 } else { 3267 NewFD->setObjectOfFriendDecl(true); 3268 } 3269 NewFD->setAccess(Access); 3270 } 3271 3272 // If we have a function template, check the template parameter 3273 // list. This will check and merge default template arguments. 3274 if (FunctionTemplate) { 3275 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3276 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3277 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3278 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3279 : TPC_FunctionTemplate); 3280 } 3281 3282 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3283 // Fake up an access specifier if it's supposed to be a class member. 3284 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3285 NewFD->setAccess(AS_public); 3286 3287 // An out-of-line member function declaration must also be a 3288 // definition (C++ [dcl.meaning]p1). 3289 // Note that this is not the case for explicit specializations of 3290 // function templates or member functions of class templates, per 3291 // C++ [temp.expl.spec]p2. 3292 if (!IsFunctionDefinition && !isFriend && 3293 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3294 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3295 << D.getCXXScopeSpec().getRange(); 3296 NewFD->setInvalidDecl(); 3297 } else if (!Redeclaration && 3298 !(isFriend && CurContext->isDependentContext())) { 3299 // The user tried to provide an out-of-line definition for a 3300 // function that is a member of a class or namespace, but there 3301 // was no such member function declared (C++ [class.mfct]p2, 3302 // C++ [namespace.memdef]p2). For example: 3303 // 3304 // class X { 3305 // void f() const; 3306 // }; 3307 // 3308 // void X::f() { } // ill-formed 3309 // 3310 // Complain about this problem, and attempt to suggest close 3311 // matches (e.g., those that differ only in cv-qualifiers and 3312 // whether the parameter types are references). 3313 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3314 << Name << DC << D.getCXXScopeSpec().getRange(); 3315 NewFD->setInvalidDecl(); 3316 3317 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3318 ForRedeclaration); 3319 LookupQualifiedName(Prev, DC); 3320 assert(!Prev.isAmbiguous() && 3321 "Cannot have an ambiguity in previous-declaration lookup"); 3322 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3323 Func != FuncEnd; ++Func) { 3324 if (isa<FunctionDecl>(*Func) && 3325 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3326 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3327 } 3328 } 3329 } 3330 3331 // Handle attributes. We need to have merged decls when handling attributes 3332 // (for example to check for conflicts, etc). 3333 // FIXME: This needs to happen before we merge declarations. Then, 3334 // let attribute merging cope with attribute conflicts. 3335 ProcessDeclAttributes(S, NewFD, D); 3336 3337 // attributes declared post-definition are currently ignored 3338 if (Redeclaration && Previous.isSingleResult()) { 3339 const FunctionDecl *Def; 3340 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3341 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3342 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3343 Diag(Def->getLocation(), diag::note_previous_definition); 3344 } 3345 } 3346 3347 AddKnownFunctionAttributes(NewFD); 3348 3349 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3350 // If a function name is overloadable in C, then every function 3351 // with that name must be marked "overloadable". 3352 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3353 << Redeclaration << NewFD; 3354 if (!Previous.empty()) 3355 Diag(Previous.getRepresentativeDecl()->getLocation(), 3356 diag::note_attribute_overloadable_prev_overload); 3357 NewFD->addAttr(::new (Context) OverloadableAttr()); 3358 } 3359 3360 // If this is a locally-scoped extern C function, update the 3361 // map of such names. 3362 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3363 && !NewFD->isInvalidDecl()) 3364 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3365 3366 // Set this FunctionDecl's range up to the right paren. 3367 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3368 3369 if (FunctionTemplate && NewFD->isInvalidDecl()) 3370 FunctionTemplate->setInvalidDecl(); 3371 3372 if (FunctionTemplate) 3373 return FunctionTemplate; 3374 3375 3376 // Keep track of static, non-inlined function definitions that 3377 // have not been used. We will warn later. 3378 // FIXME: Also include static functions declared but not defined. 3379 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3380 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3381 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3382 && !NewFD->hasAttr<ConstructorAttr>() 3383 && !NewFD->hasAttr<DestructorAttr>()) 3384 UnusedStaticFuncs.push_back(NewFD); 3385 3386 return NewFD; 3387} 3388 3389/// \brief Perform semantic checking of a new function declaration. 3390/// 3391/// Performs semantic analysis of the new function declaration 3392/// NewFD. This routine performs all semantic checking that does not 3393/// require the actual declarator involved in the declaration, and is 3394/// used both for the declaration of functions as they are parsed 3395/// (called via ActOnDeclarator) and for the declaration of functions 3396/// that have been instantiated via C++ template instantiation (called 3397/// via InstantiateDecl). 3398/// 3399/// \param IsExplicitSpecialiation whether this new function declaration is 3400/// an explicit specialization of the previous declaration. 3401/// 3402/// This sets NewFD->isInvalidDecl() to true if there was an error. 3403void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3404 LookupResult &Previous, 3405 bool IsExplicitSpecialization, 3406 bool &Redeclaration, 3407 bool &OverloadableAttrRequired) { 3408 // If NewFD is already known erroneous, don't do any of this checking. 3409 if (NewFD->isInvalidDecl()) 3410 return; 3411 3412 if (NewFD->getResultType()->isVariablyModifiedType()) { 3413 // Functions returning a variably modified type violate C99 6.7.5.2p2 3414 // because all functions have linkage. 3415 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3416 return NewFD->setInvalidDecl(); 3417 } 3418 3419 if (NewFD->isMain()) 3420 CheckMain(NewFD); 3421 3422 // Check for a previous declaration of this name. 3423 if (Previous.empty() && NewFD->isExternC()) { 3424 // Since we did not find anything by this name and we're declaring 3425 // an extern "C" function, look for a non-visible extern "C" 3426 // declaration with the same name. 3427 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3428 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3429 if (Pos != LocallyScopedExternalDecls.end()) 3430 Previous.addDecl(Pos->second); 3431 } 3432 3433 // Merge or overload the declaration with an existing declaration of 3434 // the same name, if appropriate. 3435 if (!Previous.empty()) { 3436 // Determine whether NewFD is an overload of PrevDecl or 3437 // a declaration that requires merging. If it's an overload, 3438 // there's no more work to do here; we'll just add the new 3439 // function to the scope. 3440 3441 NamedDecl *OldDecl = 0; 3442 if (!AllowOverloadingOfFunction(Previous, Context)) { 3443 Redeclaration = true; 3444 OldDecl = Previous.getFoundDecl(); 3445 } else { 3446 if (!getLangOptions().CPlusPlus) { 3447 OverloadableAttrRequired = true; 3448 3449 // Functions marked "overloadable" must have a prototype (that 3450 // we can't get through declaration merging). 3451 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3452 Diag(NewFD->getLocation(), 3453 diag::err_attribute_overloadable_no_prototype) 3454 << NewFD; 3455 Redeclaration = true; 3456 3457 // Turn this into a variadic function with no parameters. 3458 QualType R = Context.getFunctionType( 3459 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3460 0, 0, true, 0, false, false, 0, 0, 3461 FunctionType::ExtInfo()); 3462 NewFD->setType(R); 3463 return NewFD->setInvalidDecl(); 3464 } 3465 } 3466 3467 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3468 case Ovl_Match: 3469 Redeclaration = true; 3470 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3471 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3472 Redeclaration = false; 3473 } 3474 break; 3475 3476 case Ovl_NonFunction: 3477 Redeclaration = true; 3478 break; 3479 3480 case Ovl_Overload: 3481 Redeclaration = false; 3482 break; 3483 } 3484 } 3485 3486 if (Redeclaration) { 3487 // NewFD and OldDecl represent declarations that need to be 3488 // merged. 3489 if (MergeFunctionDecl(NewFD, OldDecl)) 3490 return NewFD->setInvalidDecl(); 3491 3492 Previous.clear(); 3493 Previous.addDecl(OldDecl); 3494 3495 if (FunctionTemplateDecl *OldTemplateDecl 3496 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3497 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3498 FunctionTemplateDecl *NewTemplateDecl 3499 = NewFD->getDescribedFunctionTemplate(); 3500 assert(NewTemplateDecl && "Template/non-template mismatch"); 3501 if (CXXMethodDecl *Method 3502 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3503 Method->setAccess(OldTemplateDecl->getAccess()); 3504 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3505 } 3506 3507 // If this is an explicit specialization of a member that is a function 3508 // template, mark it as a member specialization. 3509 if (IsExplicitSpecialization && 3510 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3511 NewTemplateDecl->setMemberSpecialization(); 3512 assert(OldTemplateDecl->isMemberSpecialization()); 3513 } 3514 } else { 3515 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3516 NewFD->setAccess(OldDecl->getAccess()); 3517 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3518 } 3519 } 3520 } 3521 3522 // Semantic checking for this function declaration (in isolation). 3523 if (getLangOptions().CPlusPlus) { 3524 // C++-specific checks. 3525 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3526 CheckConstructor(Constructor); 3527 } else if (CXXDestructorDecl *Destructor = 3528 dyn_cast<CXXDestructorDecl>(NewFD)) { 3529 CXXRecordDecl *Record = Destructor->getParent(); 3530 QualType ClassType = Context.getTypeDeclType(Record); 3531 3532 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3533 // type is dependent? Both gcc and edg can handle that. 3534 if (!ClassType->isDependentType()) { 3535 DeclarationName Name 3536 = Context.DeclarationNames.getCXXDestructorName( 3537 Context.getCanonicalType(ClassType)); 3538 if (NewFD->getDeclName() != Name) { 3539 Diag(NewFD->getLocation(), diag::err_destructor_name); 3540 return NewFD->setInvalidDecl(); 3541 } 3542 } 3543 3544 Record->setUserDeclaredDestructor(true); 3545 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3546 // user-defined destructor. 3547 Record->setPOD(false); 3548 3549 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3550 // declared destructor. 3551 // FIXME: C++0x: don't do this for "= default" destructors 3552 Record->setHasTrivialDestructor(false); 3553 } else if (CXXConversionDecl *Conversion 3554 = dyn_cast<CXXConversionDecl>(NewFD)) { 3555 ActOnConversionDeclarator(Conversion); 3556 } 3557 3558 // Find any virtual functions that this function overrides. 3559 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3560 if (!Method->isFunctionTemplateSpecialization() && 3561 !Method->getDescribedFunctionTemplate()) 3562 AddOverriddenMethods(Method->getParent(), Method); 3563 } 3564 3565 // Additional checks for the destructor; make sure we do this after we 3566 // figure out whether the destructor is virtual. 3567 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3568 if (!Destructor->getParent()->isDependentType()) 3569 CheckDestructor(Destructor); 3570 3571 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3572 if (NewFD->isOverloadedOperator() && 3573 CheckOverloadedOperatorDeclaration(NewFD)) 3574 return NewFD->setInvalidDecl(); 3575 3576 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3577 if (NewFD->getLiteralIdentifier() && 3578 CheckLiteralOperatorDeclaration(NewFD)) 3579 return NewFD->setInvalidDecl(); 3580 3581 // In C++, check default arguments now that we have merged decls. Unless 3582 // the lexical context is the class, because in this case this is done 3583 // during delayed parsing anyway. 3584 if (!CurContext->isRecord()) 3585 CheckCXXDefaultArguments(NewFD); 3586 } 3587} 3588 3589void Sema::CheckMain(FunctionDecl* FD) { 3590 // C++ [basic.start.main]p3: A program that declares main to be inline 3591 // or static is ill-formed. 3592 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3593 // shall not appear in a declaration of main. 3594 // static main is not an error under C99, but we should warn about it. 3595 bool isInline = FD->isInlineSpecified(); 3596 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3597 if (isInline || isStatic) { 3598 unsigned diagID = diag::warn_unusual_main_decl; 3599 if (isInline || getLangOptions().CPlusPlus) 3600 diagID = diag::err_unusual_main_decl; 3601 3602 int which = isStatic + (isInline << 1) - 1; 3603 Diag(FD->getLocation(), diagID) << which; 3604 } 3605 3606 QualType T = FD->getType(); 3607 assert(T->isFunctionType() && "function decl is not of function type"); 3608 const FunctionType* FT = T->getAs<FunctionType>(); 3609 3610 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3611 // TODO: add a replacement fixit to turn the return type into 'int'. 3612 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3613 FD->setInvalidDecl(true); 3614 } 3615 3616 // Treat protoless main() as nullary. 3617 if (isa<FunctionNoProtoType>(FT)) return; 3618 3619 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3620 unsigned nparams = FTP->getNumArgs(); 3621 assert(FD->getNumParams() == nparams); 3622 3623 bool HasExtraParameters = (nparams > 3); 3624 3625 // Darwin passes an undocumented fourth argument of type char**. If 3626 // other platforms start sprouting these, the logic below will start 3627 // getting shifty. 3628 if (nparams == 4 && 3629 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3630 HasExtraParameters = false; 3631 3632 if (HasExtraParameters) { 3633 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3634 FD->setInvalidDecl(true); 3635 nparams = 3; 3636 } 3637 3638 // FIXME: a lot of the following diagnostics would be improved 3639 // if we had some location information about types. 3640 3641 QualType CharPP = 3642 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3643 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3644 3645 for (unsigned i = 0; i < nparams; ++i) { 3646 QualType AT = FTP->getArgType(i); 3647 3648 bool mismatch = true; 3649 3650 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3651 mismatch = false; 3652 else if (Expected[i] == CharPP) { 3653 // As an extension, the following forms are okay: 3654 // char const ** 3655 // char const * const * 3656 // char * const * 3657 3658 QualifierCollector qs; 3659 const PointerType* PT; 3660 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3661 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3662 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3663 qs.removeConst(); 3664 mismatch = !qs.empty(); 3665 } 3666 } 3667 3668 if (mismatch) { 3669 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3670 // TODO: suggest replacing given type with expected type 3671 FD->setInvalidDecl(true); 3672 } 3673 } 3674 3675 if (nparams == 1 && !FD->isInvalidDecl()) { 3676 Diag(FD->getLocation(), diag::warn_main_one_arg); 3677 } 3678} 3679 3680bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3681 // FIXME: Need strict checking. In C89, we need to check for 3682 // any assignment, increment, decrement, function-calls, or 3683 // commas outside of a sizeof. In C99, it's the same list, 3684 // except that the aforementioned are allowed in unevaluated 3685 // expressions. Everything else falls under the 3686 // "may accept other forms of constant expressions" exception. 3687 // (We never end up here for C++, so the constant expression 3688 // rules there don't matter.) 3689 if (Init->isConstantInitializer(Context)) 3690 return false; 3691 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3692 << Init->getSourceRange(); 3693 return true; 3694} 3695 3696void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3697 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3698} 3699 3700/// AddInitializerToDecl - Adds the initializer Init to the 3701/// declaration dcl. If DirectInit is true, this is C++ direct 3702/// initialization rather than copy initialization. 3703void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3704 Decl *RealDecl = dcl.getAs<Decl>(); 3705 // If there is no declaration, there was an error parsing it. Just ignore 3706 // the initializer. 3707 if (RealDecl == 0) 3708 return; 3709 3710 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3711 // With declarators parsed the way they are, the parser cannot 3712 // distinguish between a normal initializer and a pure-specifier. 3713 // Thus this grotesque test. 3714 IntegerLiteral *IL; 3715 Expr *Init = static_cast<Expr *>(init.get()); 3716 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3717 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3718 CheckPureMethod(Method, Init->getSourceRange()); 3719 else { 3720 Diag(Method->getLocation(), diag::err_member_function_initialization) 3721 << Method->getDeclName() << Init->getSourceRange(); 3722 Method->setInvalidDecl(); 3723 } 3724 return; 3725 } 3726 3727 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3728 if (!VDecl) { 3729 if (getLangOptions().CPlusPlus && 3730 RealDecl->getLexicalDeclContext()->isRecord() && 3731 isa<NamedDecl>(RealDecl)) 3732 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3733 << cast<NamedDecl>(RealDecl)->getDeclName(); 3734 else 3735 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3736 RealDecl->setInvalidDecl(); 3737 return; 3738 } 3739 3740 // A definition must end up with a complete type, which means it must be 3741 // complete with the restriction that an array type might be completed by the 3742 // initializer; note that later code assumes this restriction. 3743 QualType BaseDeclType = VDecl->getType(); 3744 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3745 BaseDeclType = Array->getElementType(); 3746 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3747 diag::err_typecheck_decl_incomplete_type)) { 3748 RealDecl->setInvalidDecl(); 3749 return; 3750 } 3751 3752 // The variable can not have an abstract class type. 3753 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3754 diag::err_abstract_type_in_decl, 3755 AbstractVariableType)) 3756 VDecl->setInvalidDecl(); 3757 3758 const VarDecl *Def; 3759 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3760 Diag(VDecl->getLocation(), diag::err_redefinition) 3761 << VDecl->getDeclName(); 3762 Diag(Def->getLocation(), diag::note_previous_definition); 3763 VDecl->setInvalidDecl(); 3764 return; 3765 } 3766 3767 // Take ownership of the expression, now that we're sure we have somewhere 3768 // to put it. 3769 Expr *Init = init.takeAs<Expr>(); 3770 assert(Init && "missing initializer"); 3771 3772 // Capture the variable that is being initialized and the style of 3773 // initialization. 3774 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3775 3776 // FIXME: Poor source location information. 3777 InitializationKind Kind 3778 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3779 Init->getLocStart(), 3780 Init->getLocEnd()) 3781 : InitializationKind::CreateCopy(VDecl->getLocation(), 3782 Init->getLocStart()); 3783 3784 // Get the decls type and save a reference for later, since 3785 // CheckInitializerTypes may change it. 3786 QualType DclT = VDecl->getType(), SavT = DclT; 3787 if (VDecl->isBlockVarDecl()) { 3788 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3789 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3790 VDecl->setInvalidDecl(); 3791 } else if (!VDecl->isInvalidDecl()) { 3792 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3793 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3794 MultiExprArg(*this, (void**)&Init, 1), 3795 &DclT); 3796 if (Result.isInvalid()) { 3797 VDecl->setInvalidDecl(); 3798 return; 3799 } 3800 3801 Init = Result.takeAs<Expr>(); 3802 3803 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3804 // Don't check invalid declarations to avoid emitting useless diagnostics. 3805 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3806 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3807 CheckForConstantInitializer(Init, DclT); 3808 } 3809 } 3810 } else if (VDecl->isStaticDataMember() && 3811 VDecl->getLexicalDeclContext()->isRecord()) { 3812 // This is an in-class initialization for a static data member, e.g., 3813 // 3814 // struct S { 3815 // static const int value = 17; 3816 // }; 3817 3818 // Attach the initializer 3819 VDecl->setInit(Init); 3820 3821 // C++ [class.mem]p4: 3822 // A member-declarator can contain a constant-initializer only 3823 // if it declares a static member (9.4) of const integral or 3824 // const enumeration type, see 9.4.2. 3825 QualType T = VDecl->getType(); 3826 if (!T->isDependentType() && 3827 (!Context.getCanonicalType(T).isConstQualified() || 3828 !T->isIntegralType())) { 3829 Diag(VDecl->getLocation(), diag::err_member_initialization) 3830 << VDecl->getDeclName() << Init->getSourceRange(); 3831 VDecl->setInvalidDecl(); 3832 } else { 3833 // C++ [class.static.data]p4: 3834 // If a static data member is of const integral or const 3835 // enumeration type, its declaration in the class definition 3836 // can specify a constant-initializer which shall be an 3837 // integral constant expression (5.19). 3838 if (!Init->isTypeDependent() && 3839 !Init->getType()->isIntegralType()) { 3840 // We have a non-dependent, non-integral or enumeration type. 3841 Diag(Init->getSourceRange().getBegin(), 3842 diag::err_in_class_initializer_non_integral_type) 3843 << Init->getType() << Init->getSourceRange(); 3844 VDecl->setInvalidDecl(); 3845 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3846 // Check whether the expression is a constant expression. 3847 llvm::APSInt Value; 3848 SourceLocation Loc; 3849 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3850 Diag(Loc, diag::err_in_class_initializer_non_constant) 3851 << Init->getSourceRange(); 3852 VDecl->setInvalidDecl(); 3853 } else if (!VDecl->getType()->isDependentType()) 3854 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3855 } 3856 } 3857 } else if (VDecl->isFileVarDecl()) { 3858 if (VDecl->getStorageClass() == VarDecl::Extern && 3859 (!getLangOptions().CPlusPlus || 3860 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 3861 Diag(VDecl->getLocation(), diag::warn_extern_init); 3862 if (!VDecl->isInvalidDecl()) { 3863 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3864 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3865 MultiExprArg(*this, (void**)&Init, 1), 3866 &DclT); 3867 if (Result.isInvalid()) { 3868 VDecl->setInvalidDecl(); 3869 return; 3870 } 3871 3872 Init = Result.takeAs<Expr>(); 3873 } 3874 3875 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3876 // Don't check invalid declarations to avoid emitting useless diagnostics. 3877 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3878 // C99 6.7.8p4. All file scoped initializers need to be constant. 3879 CheckForConstantInitializer(Init, DclT); 3880 } 3881 } 3882 // If the type changed, it means we had an incomplete type that was 3883 // completed by the initializer. For example: 3884 // int ary[] = { 1, 3, 5 }; 3885 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3886 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3887 VDecl->setType(DclT); 3888 Init->setType(DclT); 3889 } 3890 3891 Init = MaybeCreateCXXExprWithTemporaries(Init); 3892 // Attach the initializer to the decl. 3893 VDecl->setInit(Init); 3894 3895 if (getLangOptions().CPlusPlus) { 3896 // Make sure we mark the destructor as used if necessary. 3897 QualType InitType = VDecl->getType(); 3898 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3899 InitType = Context.getBaseElementType(Array); 3900 if (const RecordType *Record = InitType->getAs<RecordType>()) 3901 FinalizeVarWithDestructor(VDecl, Record); 3902 } 3903 3904 return; 3905} 3906 3907/// ActOnInitializerError - Given that there was an error parsing an 3908/// initializer for the given declaration, try to return to some form 3909/// of sanity. 3910void Sema::ActOnInitializerError(DeclPtrTy dcl) { 3911 // Our main concern here is re-establishing invariants like "a 3912 // variable's type is either dependent or complete". 3913 Decl *D = dcl.getAs<Decl>(); 3914 if (!D || D->isInvalidDecl()) return; 3915 3916 VarDecl *VD = dyn_cast<VarDecl>(D); 3917 if (!VD) return; 3918 3919 QualType Ty = VD->getType(); 3920 if (Ty->isDependentType()) return; 3921 3922 // Require a complete type. 3923 if (RequireCompleteType(VD->getLocation(), 3924 Context.getBaseElementType(Ty), 3925 diag::err_typecheck_decl_incomplete_type)) { 3926 VD->setInvalidDecl(); 3927 return; 3928 } 3929 3930 // Require an abstract type. 3931 if (RequireNonAbstractType(VD->getLocation(), Ty, 3932 diag::err_abstract_type_in_decl, 3933 AbstractVariableType)) { 3934 VD->setInvalidDecl(); 3935 return; 3936 } 3937 3938 // Don't bother complaining about constructors or destructors, 3939 // though. 3940} 3941 3942void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3943 bool TypeContainsUndeducedAuto) { 3944 Decl *RealDecl = dcl.getAs<Decl>(); 3945 3946 // If there is no declaration, there was an error parsing it. Just ignore it. 3947 if (RealDecl == 0) 3948 return; 3949 3950 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3951 QualType Type = Var->getType(); 3952 3953 // C++0x [dcl.spec.auto]p3 3954 if (TypeContainsUndeducedAuto) { 3955 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3956 << Var->getDeclName() << Type; 3957 Var->setInvalidDecl(); 3958 return; 3959 } 3960 3961 switch (Var->isThisDeclarationADefinition()) { 3962 case VarDecl::Definition: 3963 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 3964 break; 3965 3966 // We have an out-of-line definition of a static data member 3967 // that has an in-class initializer, so we type-check this like 3968 // a declaration. 3969 // 3970 // Fall through 3971 3972 case VarDecl::DeclarationOnly: 3973 // It's only a declaration. 3974 3975 // Block scope. C99 6.7p7: If an identifier for an object is 3976 // declared with no linkage (C99 6.2.2p6), the type for the 3977 // object shall be complete. 3978 if (!Type->isDependentType() && Var->isBlockVarDecl() && 3979 !Var->getLinkage() && !Var->isInvalidDecl() && 3980 RequireCompleteType(Var->getLocation(), Type, 3981 diag::err_typecheck_decl_incomplete_type)) 3982 Var->setInvalidDecl(); 3983 3984 // Make sure that the type is not abstract. 3985 if (!Type->isDependentType() && !Var->isInvalidDecl() && 3986 RequireNonAbstractType(Var->getLocation(), Type, 3987 diag::err_abstract_type_in_decl, 3988 AbstractVariableType)) 3989 Var->setInvalidDecl(); 3990 return; 3991 3992 case VarDecl::TentativeDefinition: 3993 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3994 // object that has file scope without an initializer, and without a 3995 // storage-class specifier or with the storage-class specifier "static", 3996 // constitutes a tentative definition. Note: A tentative definition with 3997 // external linkage is valid (C99 6.2.2p5). 3998 if (!Var->isInvalidDecl()) { 3999 if (const IncompleteArrayType *ArrayT 4000 = Context.getAsIncompleteArrayType(Type)) { 4001 if (RequireCompleteType(Var->getLocation(), 4002 ArrayT->getElementType(), 4003 diag::err_illegal_decl_array_incomplete_type)) 4004 Var->setInvalidDecl(); 4005 } else if (Var->getStorageClass() == VarDecl::Static) { 4006 // C99 6.9.2p3: If the declaration of an identifier for an object is 4007 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4008 // declared type shall not be an incomplete type. 4009 // NOTE: code such as the following 4010 // static struct s; 4011 // struct s { int a; }; 4012 // is accepted by gcc. Hence here we issue a warning instead of 4013 // an error and we do not invalidate the static declaration. 4014 // NOTE: to avoid multiple warnings, only check the first declaration. 4015 if (Var->getPreviousDeclaration() == 0) 4016 RequireCompleteType(Var->getLocation(), Type, 4017 diag::ext_typecheck_decl_incomplete_type); 4018 } 4019 } 4020 4021 // Record the tentative definition; we're done. 4022 if (!Var->isInvalidDecl()) 4023 TentativeDefinitions.push_back(Var); 4024 return; 4025 } 4026 4027 // Provide a specific diagnostic for uninitialized variable 4028 // definitions with incomplete array type. 4029 if (Type->isIncompleteArrayType()) { 4030 Diag(Var->getLocation(), 4031 diag::err_typecheck_incomplete_array_needs_initializer); 4032 Var->setInvalidDecl(); 4033 return; 4034 } 4035 4036 // Provide a specific diagnostic for uninitialized variable 4037 // definitions with reference type. 4038 if (Type->isReferenceType()) { 4039 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4040 << Var->getDeclName() 4041 << SourceRange(Var->getLocation(), Var->getLocation()); 4042 Var->setInvalidDecl(); 4043 return; 4044 } 4045 4046 // Do not attempt to type-check the default initializer for a 4047 // variable with dependent type. 4048 if (Type->isDependentType()) 4049 return; 4050 4051 if (Var->isInvalidDecl()) 4052 return; 4053 4054 if (RequireCompleteType(Var->getLocation(), 4055 Context.getBaseElementType(Type), 4056 diag::err_typecheck_decl_incomplete_type)) { 4057 Var->setInvalidDecl(); 4058 return; 4059 } 4060 4061 // The variable can not have an abstract class type. 4062 if (RequireNonAbstractType(Var->getLocation(), Type, 4063 diag::err_abstract_type_in_decl, 4064 AbstractVariableType)) { 4065 Var->setInvalidDecl(); 4066 return; 4067 } 4068 4069 const RecordType *Record 4070 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4071 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4072 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4073 // C++03 [dcl.init]p9: 4074 // If no initializer is specified for an object, and the 4075 // object is of (possibly cv-qualified) non-POD class type (or 4076 // array thereof), the object shall be default-initialized; if 4077 // the object is of const-qualified type, the underlying class 4078 // type shall have a user-declared default 4079 // constructor. Otherwise, if no initializer is specified for 4080 // a non- static object, the object and its subobjects, if 4081 // any, have an indeterminate initial value); if the object 4082 // or any of its subobjects are of const-qualified type, the 4083 // program is ill-formed. 4084 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4085 } else { 4086 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4087 InitializationKind Kind 4088 = InitializationKind::CreateDefault(Var->getLocation()); 4089 4090 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4091 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4092 MultiExprArg(*this, 0, 0)); 4093 if (Init.isInvalid()) 4094 Var->setInvalidDecl(); 4095 else if (Init.get()) 4096 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4097 } 4098 4099 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4100 FinalizeVarWithDestructor(Var, Record); 4101 } 4102} 4103 4104Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4105 DeclPtrTy *Group, 4106 unsigned NumDecls) { 4107 llvm::SmallVector<Decl*, 8> Decls; 4108 4109 if (DS.isTypeSpecOwned()) 4110 Decls.push_back((Decl*)DS.getTypeRep()); 4111 4112 for (unsigned i = 0; i != NumDecls; ++i) 4113 if (Decl *D = Group[i].getAs<Decl>()) 4114 Decls.push_back(D); 4115 4116 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4117 Decls.data(), Decls.size())); 4118} 4119 4120 4121/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4122/// to introduce parameters into function prototype scope. 4123Sema::DeclPtrTy 4124Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4125 const DeclSpec &DS = D.getDeclSpec(); 4126 4127 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4128 VarDecl::StorageClass StorageClass = VarDecl::None; 4129 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4130 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4131 StorageClass = VarDecl::Register; 4132 StorageClassAsWritten = VarDecl::Register; 4133 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4134 Diag(DS.getStorageClassSpecLoc(), 4135 diag::err_invalid_storage_class_in_func_decl); 4136 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4137 } 4138 4139 if (D.getDeclSpec().isThreadSpecified()) 4140 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4141 4142 DiagnoseFunctionSpecifiers(D); 4143 4144 // Check that there are no default arguments inside the type of this 4145 // parameter (C++ only). 4146 if (getLangOptions().CPlusPlus) 4147 CheckExtraCXXDefaultArguments(D); 4148 4149 TypeSourceInfo *TInfo = 0; 4150 TagDecl *OwnedDecl = 0; 4151 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4152 4153 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4154 // C++ [dcl.fct]p6: 4155 // Types shall not be defined in return or parameter types. 4156 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4157 << Context.getTypeDeclType(OwnedDecl); 4158 } 4159 4160 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4161 IdentifierInfo *II = D.getIdentifier(); 4162 if (II) { 4163 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4164 ForRedeclaration); 4165 LookupName(R, S); 4166 if (R.isSingleResult()) { 4167 NamedDecl *PrevDecl = R.getFoundDecl(); 4168 if (PrevDecl->isTemplateParameter()) { 4169 // Maybe we will complain about the shadowed template parameter. 4170 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4171 // Just pretend that we didn't see the previous declaration. 4172 PrevDecl = 0; 4173 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4174 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4175 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4176 4177 // Recover by removing the name 4178 II = 0; 4179 D.SetIdentifier(0, D.getIdentifierLoc()); 4180 D.setInvalidType(true); 4181 } 4182 } 4183 } 4184 4185 // Temporarily put parameter variables in the translation unit, not 4186 // the enclosing context. This prevents them from accidentally 4187 // looking like class members in C++. 4188 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4189 TInfo, parmDeclType, II, 4190 D.getIdentifierLoc(), 4191 StorageClass, StorageClassAsWritten); 4192 4193 if (D.isInvalidType()) 4194 New->setInvalidDecl(); 4195 4196 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4197 if (D.getCXXScopeSpec().isSet()) { 4198 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4199 << D.getCXXScopeSpec().getRange(); 4200 New->setInvalidDecl(); 4201 } 4202 4203 // Add the parameter declaration into this scope. 4204 S->AddDecl(DeclPtrTy::make(New)); 4205 if (II) 4206 IdResolver.AddDecl(New); 4207 4208 ProcessDeclAttributes(S, New, D); 4209 4210 if (New->hasAttr<BlocksAttr>()) { 4211 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4212 } 4213 return DeclPtrTy::make(New); 4214} 4215 4216ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4217 TypeSourceInfo *TSInfo, QualType T, 4218 IdentifierInfo *Name, 4219 SourceLocation NameLoc, 4220 VarDecl::StorageClass StorageClass, 4221 VarDecl::StorageClass StorageClassAsWritten) { 4222 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4223 adjustParameterType(T), TSInfo, 4224 StorageClass, StorageClassAsWritten, 4225 0); 4226 4227 // Parameters can not be abstract class types. 4228 // For record types, this is done by the AbstractClassUsageDiagnoser once 4229 // the class has been completely parsed. 4230 if (!CurContext->isRecord() && 4231 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4232 AbstractParamType)) 4233 New->setInvalidDecl(); 4234 4235 // Parameter declarators cannot be interface types. All ObjC objects are 4236 // passed by reference. 4237 if (T->isObjCInterfaceType()) { 4238 Diag(NameLoc, 4239 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4240 New->setInvalidDecl(); 4241 } 4242 4243 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4244 // duration shall not be qualified by an address-space qualifier." 4245 // Since all parameters have automatic store duration, they can not have 4246 // an address space. 4247 if (T.getAddressSpace() != 0) { 4248 Diag(NameLoc, diag::err_arg_with_address_space); 4249 New->setInvalidDecl(); 4250 } 4251 4252 return New; 4253} 4254 4255void Sema::ActOnObjCCatchParam(DeclPtrTy D) { 4256 ParmVarDecl *Param = cast<ParmVarDecl>(D.getAs<Decl>()); 4257 Param->setDeclContext(CurContext); 4258} 4259 4260void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4261 SourceLocation LocAfterDecls) { 4262 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4263 "Not a function declarator!"); 4264 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4265 4266 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4267 // for a K&R function. 4268 if (!FTI.hasPrototype) { 4269 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4270 --i; 4271 if (FTI.ArgInfo[i].Param == 0) { 4272 llvm::SmallString<256> Code; 4273 llvm::raw_svector_ostream(Code) << " int " 4274 << FTI.ArgInfo[i].Ident->getName() 4275 << ";\n"; 4276 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4277 << FTI.ArgInfo[i].Ident 4278 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4279 4280 // Implicitly declare the argument as type 'int' for lack of a better 4281 // type. 4282 DeclSpec DS; 4283 const char* PrevSpec; // unused 4284 unsigned DiagID; // unused 4285 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4286 PrevSpec, DiagID); 4287 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4288 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4289 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4290 } 4291 } 4292 } 4293} 4294 4295Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4296 Declarator &D) { 4297 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4298 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4299 "Not a function declarator!"); 4300 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4301 4302 if (FTI.hasPrototype) { 4303 // FIXME: Diagnose arguments without names in C. 4304 } 4305 4306 Scope *ParentScope = FnBodyScope->getParent(); 4307 4308 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4309 MultiTemplateParamsArg(*this), 4310 /*IsFunctionDefinition=*/true); 4311 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4312} 4313 4314static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4315 // Don't warn about invalid declarations. 4316 if (FD->isInvalidDecl()) 4317 return false; 4318 4319 // Or declarations that aren't global. 4320 if (!FD->isGlobal()) 4321 return false; 4322 4323 // Don't warn about C++ member functions. 4324 if (isa<CXXMethodDecl>(FD)) 4325 return false; 4326 4327 // Don't warn about 'main'. 4328 if (FD->isMain()) 4329 return false; 4330 4331 // Don't warn about inline functions. 4332 if (FD->isInlineSpecified()) 4333 return false; 4334 4335 // Don't warn about function templates. 4336 if (FD->getDescribedFunctionTemplate()) 4337 return false; 4338 4339 // Don't warn about function template specializations. 4340 if (FD->isFunctionTemplateSpecialization()) 4341 return false; 4342 4343 bool MissingPrototype = true; 4344 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4345 Prev; Prev = Prev->getPreviousDeclaration()) { 4346 // Ignore any declarations that occur in function or method 4347 // scope, because they aren't visible from the header. 4348 if (Prev->getDeclContext()->isFunctionOrMethod()) 4349 continue; 4350 4351 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4352 break; 4353 } 4354 4355 return MissingPrototype; 4356} 4357 4358Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4359 // Clear the last template instantiation error context. 4360 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4361 4362 if (!D) 4363 return D; 4364 FunctionDecl *FD = 0; 4365 4366 if (FunctionTemplateDecl *FunTmpl 4367 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4368 FD = FunTmpl->getTemplatedDecl(); 4369 else 4370 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4371 4372 // Enter a new function scope 4373 PushFunctionScope(); 4374 4375 // See if this is a redefinition. 4376 // But don't complain if we're in GNU89 mode and the previous definition 4377 // was an extern inline function. 4378 const FunctionDecl *Definition; 4379 if (FD->getBody(Definition) && 4380 !canRedefineFunction(Definition, getLangOptions())) { 4381 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4382 Diag(Definition->getLocation(), diag::note_previous_definition); 4383 } 4384 4385 // Builtin functions cannot be defined. 4386 if (unsigned BuiltinID = FD->getBuiltinID()) { 4387 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4388 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4389 FD->setInvalidDecl(); 4390 } 4391 } 4392 4393 // The return type of a function definition must be complete 4394 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4395 QualType ResultType = FD->getResultType(); 4396 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4397 !FD->isInvalidDecl() && 4398 RequireCompleteType(FD->getLocation(), ResultType, 4399 diag::err_func_def_incomplete_result)) 4400 FD->setInvalidDecl(); 4401 4402 // GNU warning -Wmissing-prototypes: 4403 // Warn if a global function is defined without a previous 4404 // prototype declaration. This warning is issued even if the 4405 // definition itself provides a prototype. The aim is to detect 4406 // global functions that fail to be declared in header files. 4407 if (ShouldWarnAboutMissingPrototype(FD)) 4408 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4409 4410 if (FnBodyScope) 4411 PushDeclContext(FnBodyScope, FD); 4412 4413 // Check the validity of our function parameters 4414 CheckParmsForFunctionDef(FD); 4415 4416 bool ShouldCheckShadow = 4417 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4418 4419 // Introduce our parameters into the function scope 4420 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4421 ParmVarDecl *Param = FD->getParamDecl(p); 4422 Param->setOwningFunction(FD); 4423 4424 // If this has an identifier, add it to the scope stack. 4425 if (Param->getIdentifier() && FnBodyScope) { 4426 if (ShouldCheckShadow) 4427 CheckShadow(FnBodyScope, Param); 4428 4429 PushOnScopeChains(Param, FnBodyScope); 4430 } 4431 } 4432 4433 // Checking attributes of current function definition 4434 // dllimport attribute. 4435 if (FD->getAttr<DLLImportAttr>() && 4436 (!FD->getAttr<DLLExportAttr>())) { 4437 // dllimport attribute cannot be applied to definition. 4438 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4439 Diag(FD->getLocation(), 4440 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4441 << "dllimport"; 4442 FD->setInvalidDecl(); 4443 return DeclPtrTy::make(FD); 4444 } 4445 4446 // Visual C++ appears to not think this is an issue, so only issue 4447 // a warning when Microsoft extensions are disabled. 4448 if (!LangOpts.Microsoft) { 4449 // If a symbol previously declared dllimport is later defined, the 4450 // attribute is ignored in subsequent references, and a warning is 4451 // emitted. 4452 Diag(FD->getLocation(), 4453 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4454 << FD->getNameAsCString() << "dllimport"; 4455 } 4456 } 4457 return DeclPtrTy::make(FD); 4458} 4459 4460Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4461 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4462} 4463 4464Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4465 bool IsInstantiation) { 4466 Decl *dcl = D.getAs<Decl>(); 4467 Stmt *Body = BodyArg.takeAs<Stmt>(); 4468 4469 FunctionDecl *FD = 0; 4470 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4471 if (FunTmpl) 4472 FD = FunTmpl->getTemplatedDecl(); 4473 else 4474 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4475 4476 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4477 4478 if (FD) { 4479 FD->setBody(Body); 4480 if (FD->isMain()) { 4481 // C and C++ allow for main to automagically return 0. 4482 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4483 FD->setHasImplicitReturnZero(true); 4484 WP.disableCheckFallThrough(); 4485 } 4486 4487 if (!FD->isInvalidDecl()) 4488 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4489 4490 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4491 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4492 4493 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4494 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4495 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4496 MD->setBody(Body); 4497 MD->setEndLoc(Body->getLocEnd()); 4498 if (!MD->isInvalidDecl()) 4499 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4500 } else { 4501 Body->Destroy(Context); 4502 return DeclPtrTy(); 4503 } 4504 4505 // Verify and clean out per-function state. 4506 4507 // Check goto/label use. 4508 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4509 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4510 LabelStmt *L = I->second; 4511 4512 // Verify that we have no forward references left. If so, there was a goto 4513 // or address of a label taken, but no definition of it. Label fwd 4514 // definitions are indicated with a null substmt. 4515 if (L->getSubStmt() != 0) 4516 continue; 4517 4518 // Emit error. 4519 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4520 4521 // At this point, we have gotos that use the bogus label. Stitch it into 4522 // the function body so that they aren't leaked and that the AST is well 4523 // formed. 4524 if (Body == 0) { 4525 // The whole function wasn't parsed correctly, just delete this. 4526 L->Destroy(Context); 4527 continue; 4528 } 4529 4530 // Otherwise, the body is valid: we want to stitch the label decl into the 4531 // function somewhere so that it is properly owned and so that the goto 4532 // has a valid target. Do this by creating a new compound stmt with the 4533 // label in it. 4534 4535 // Give the label a sub-statement. 4536 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4537 4538 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4539 cast<CXXTryStmt>(Body)->getTryBlock() : 4540 cast<CompoundStmt>(Body); 4541 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4542 Compound->body_end()); 4543 Elements.push_back(L); 4544 Compound->setStmts(Context, Elements.data(), Elements.size()); 4545 } 4546 4547 if (Body) { 4548 // C++ constructors that have function-try-blocks can't have return 4549 // statements in the handlers of that block. (C++ [except.handle]p14) 4550 // Verify this. 4551 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4552 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4553 4554 // Verify that that gotos and switch cases don't jump into scopes illegally. 4555 // Verify that that gotos and switch cases don't jump into scopes illegally. 4556 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 4557 DiagnoseInvalidJumps(Body); 4558 4559 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4560 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4561 Destructor->getParent()); 4562 4563 // If any errors have occurred, clear out any temporaries that may have 4564 // been leftover. This ensures that these temporaries won't be picked up for 4565 // deletion in some later function. 4566 if (PP.getDiagnostics().hasErrorOccurred()) 4567 ExprTemporaries.clear(); 4568 else if (!isa<FunctionTemplateDecl>(dcl)) { 4569 // Since the body is valid, issue any analysis-based warnings that are 4570 // enabled. 4571 QualType ResultType; 4572 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4573 ResultType = FD->getResultType(); 4574 } 4575 else { 4576 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4577 ResultType = MD->getResultType(); 4578 } 4579 AnalysisWarnings.IssueWarnings(WP, dcl); 4580 } 4581 4582 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4583 } 4584 4585 if (!IsInstantiation) 4586 PopDeclContext(); 4587 4588 PopFunctionOrBlockScope(); 4589 4590 // If any errors have occurred, clear out any temporaries that may have 4591 // been leftover. This ensures that these temporaries won't be picked up for 4592 // deletion in some later function. 4593 if (getDiagnostics().hasErrorOccurred()) 4594 ExprTemporaries.clear(); 4595 4596 return D; 4597} 4598 4599/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4600/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4601NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4602 IdentifierInfo &II, Scope *S) { 4603 // Before we produce a declaration for an implicitly defined 4604 // function, see whether there was a locally-scoped declaration of 4605 // this name as a function or variable. If so, use that 4606 // (non-visible) declaration, and complain about it. 4607 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4608 = LocallyScopedExternalDecls.find(&II); 4609 if (Pos != LocallyScopedExternalDecls.end()) { 4610 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4611 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4612 return Pos->second; 4613 } 4614 4615 // Extension in C99. Legal in C90, but warn about it. 4616 if (II.getName().startswith("__builtin_")) 4617 Diag(Loc, diag::warn_builtin_unknown) << &II; 4618 else if (getLangOptions().C99) 4619 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4620 else 4621 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4622 4623 // Set a Declarator for the implicit definition: int foo(); 4624 const char *Dummy; 4625 DeclSpec DS; 4626 unsigned DiagID; 4627 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4628 Error = Error; // Silence warning. 4629 assert(!Error && "Error setting up implicit decl!"); 4630 Declarator D(DS, Declarator::BlockContext); 4631 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4632 0, 0, false, SourceLocation(), 4633 false, 0,0,0, Loc, Loc, D), 4634 SourceLocation()); 4635 D.SetIdentifier(&II, Loc); 4636 4637 // Insert this function into translation-unit scope. 4638 4639 DeclContext *PrevDC = CurContext; 4640 CurContext = Context.getTranslationUnitDecl(); 4641 4642 FunctionDecl *FD = 4643 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4644 FD->setImplicit(); 4645 4646 CurContext = PrevDC; 4647 4648 AddKnownFunctionAttributes(FD); 4649 4650 return FD; 4651} 4652 4653/// \brief Adds any function attributes that we know a priori based on 4654/// the declaration of this function. 4655/// 4656/// These attributes can apply both to implicitly-declared builtins 4657/// (like __builtin___printf_chk) or to library-declared functions 4658/// like NSLog or printf. 4659void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4660 if (FD->isInvalidDecl()) 4661 return; 4662 4663 // If this is a built-in function, map its builtin attributes to 4664 // actual attributes. 4665 if (unsigned BuiltinID = FD->getBuiltinID()) { 4666 // Handle printf-formatting attributes. 4667 unsigned FormatIdx; 4668 bool HasVAListArg; 4669 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4670 if (!FD->getAttr<FormatAttr>()) 4671 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4672 HasVAListArg ? 0 : FormatIdx+2)); 4673 } 4674 4675 // Mark const if we don't care about errno and that is the only 4676 // thing preventing the function from being const. This allows 4677 // IRgen to use LLVM intrinsics for such functions. 4678 if (!getLangOptions().MathErrno && 4679 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4680 if (!FD->getAttr<ConstAttr>()) 4681 FD->addAttr(::new (Context) ConstAttr()); 4682 } 4683 4684 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4685 FD->setType(Context.getNoReturnType(FD->getType())); 4686 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4687 FD->addAttr(::new (Context) NoThrowAttr()); 4688 if (Context.BuiltinInfo.isConst(BuiltinID)) 4689 FD->addAttr(::new (Context) ConstAttr()); 4690 } 4691 4692 IdentifierInfo *Name = FD->getIdentifier(); 4693 if (!Name) 4694 return; 4695 if ((!getLangOptions().CPlusPlus && 4696 FD->getDeclContext()->isTranslationUnit()) || 4697 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4698 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4699 LinkageSpecDecl::lang_c)) { 4700 // Okay: this could be a libc/libm/Objective-C function we know 4701 // about. 4702 } else 4703 return; 4704 4705 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4706 // FIXME: NSLog and NSLogv should be target specific 4707 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4708 // FIXME: We known better than our headers. 4709 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4710 } else 4711 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4712 Name->isStr("NSLogv") ? 0 : 2)); 4713 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4714 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4715 // target-specific builtins, perhaps? 4716 if (!FD->getAttr<FormatAttr>()) 4717 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4718 Name->isStr("vasprintf") ? 0 : 3)); 4719 } 4720} 4721 4722TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4723 TypeSourceInfo *TInfo) { 4724 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4725 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4726 4727 if (!TInfo) { 4728 assert(D.isInvalidType() && "no declarator info for valid type"); 4729 TInfo = Context.getTrivialTypeSourceInfo(T); 4730 } 4731 4732 // Scope manipulation handled by caller. 4733 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4734 D.getIdentifierLoc(), 4735 D.getIdentifier(), 4736 TInfo); 4737 4738 if (const TagType *TT = T->getAs<TagType>()) { 4739 TagDecl *TD = TT->getDecl(); 4740 4741 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4742 // keep track of the TypedefDecl. 4743 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4744 TD->setTypedefForAnonDecl(NewTD); 4745 } 4746 4747 if (D.isInvalidType()) 4748 NewTD->setInvalidDecl(); 4749 return NewTD; 4750} 4751 4752 4753/// \brief Determine whether a tag with a given kind is acceptable 4754/// as a redeclaration of the given tag declaration. 4755/// 4756/// \returns true if the new tag kind is acceptable, false otherwise. 4757bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4758 TagDecl::TagKind NewTag, 4759 SourceLocation NewTagLoc, 4760 const IdentifierInfo &Name) { 4761 // C++ [dcl.type.elab]p3: 4762 // The class-key or enum keyword present in the 4763 // elaborated-type-specifier shall agree in kind with the 4764 // declaration to which the name in theelaborated-type-specifier 4765 // refers. This rule also applies to the form of 4766 // elaborated-type-specifier that declares a class-name or 4767 // friend class since it can be construed as referring to the 4768 // definition of the class. Thus, in any 4769 // elaborated-type-specifier, the enum keyword shall be used to 4770 // refer to an enumeration (7.2), the union class-keyshall be 4771 // used to refer to a union (clause 9), and either the class or 4772 // struct class-key shall be used to refer to a class (clause 9) 4773 // declared using the class or struct class-key. 4774 TagDecl::TagKind OldTag = Previous->getTagKind(); 4775 if (OldTag == NewTag) 4776 return true; 4777 4778 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4779 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4780 // Warn about the struct/class tag mismatch. 4781 bool isTemplate = false; 4782 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4783 isTemplate = Record->getDescribedClassTemplate(); 4784 4785 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4786 << (NewTag == TagDecl::TK_class) 4787 << isTemplate << &Name 4788 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 4789 OldTag == TagDecl::TK_class? "class" : "struct"); 4790 Diag(Previous->getLocation(), diag::note_previous_use); 4791 return true; 4792 } 4793 return false; 4794} 4795 4796/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4797/// former case, Name will be non-null. In the later case, Name will be null. 4798/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4799/// reference/declaration/definition of a tag. 4800Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4801 SourceLocation KWLoc, CXXScopeSpec &SS, 4802 IdentifierInfo *Name, SourceLocation NameLoc, 4803 AttributeList *Attr, AccessSpecifier AS, 4804 MultiTemplateParamsArg TemplateParameterLists, 4805 bool &OwnedDecl, bool &IsDependent) { 4806 // If this is not a definition, it must have a name. 4807 assert((Name != 0 || TUK == TUK_Definition) && 4808 "Nameless record must be a definition!"); 4809 4810 OwnedDecl = false; 4811 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4812 4813 // FIXME: Check explicit specializations more carefully. 4814 bool isExplicitSpecialization = false; 4815 if (TUK != TUK_Reference) { 4816 if (TemplateParameterList *TemplateParams 4817 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4818 (TemplateParameterList**)TemplateParameterLists.get(), 4819 TemplateParameterLists.size(), 4820 TUK == TUK_Friend, 4821 isExplicitSpecialization)) { 4822 if (TemplateParams->size() > 0) { 4823 // This is a declaration or definition of a class template (which may 4824 // be a member of another template). 4825 OwnedDecl = false; 4826 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4827 SS, Name, NameLoc, Attr, 4828 TemplateParams, 4829 AS); 4830 TemplateParameterLists.release(); 4831 return Result.get(); 4832 } else { 4833 // The "template<>" header is extraneous. 4834 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4835 << ElaboratedType::getNameForTagKind(Kind) << Name; 4836 isExplicitSpecialization = true; 4837 } 4838 } 4839 4840 TemplateParameterLists.release(); 4841 } 4842 4843 DeclContext *SearchDC = CurContext; 4844 DeclContext *DC = CurContext; 4845 bool isStdBadAlloc = false; 4846 bool Invalid = false; 4847 4848 RedeclarationKind Redecl = ForRedeclaration; 4849 if (TUK == TUK_Friend || TUK == TUK_Reference) 4850 Redecl = NotForRedeclaration; 4851 4852 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4853 4854 if (Name && SS.isNotEmpty()) { 4855 // We have a nested-name tag ('struct foo::bar'). 4856 4857 // Check for invalid 'foo::'. 4858 if (SS.isInvalid()) { 4859 Name = 0; 4860 goto CreateNewDecl; 4861 } 4862 4863 // If this is a friend or a reference to a class in a dependent 4864 // context, don't try to make a decl for it. 4865 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4866 DC = computeDeclContext(SS, false); 4867 if (!DC) { 4868 IsDependent = true; 4869 return DeclPtrTy(); 4870 } 4871 } 4872 4873 if (RequireCompleteDeclContext(SS)) 4874 return DeclPtrTy::make((Decl *)0); 4875 4876 DC = computeDeclContext(SS, true); 4877 SearchDC = DC; 4878 // Look-up name inside 'foo::'. 4879 LookupQualifiedName(Previous, DC); 4880 4881 if (Previous.isAmbiguous()) 4882 return DeclPtrTy(); 4883 4884 if (Previous.empty()) { 4885 // Name lookup did not find anything. However, if the 4886 // nested-name-specifier refers to the current instantiation, 4887 // and that current instantiation has any dependent base 4888 // classes, we might find something at instantiation time: treat 4889 // this as a dependent elaborated-type-specifier. 4890 if (Previous.wasNotFoundInCurrentInstantiation()) { 4891 IsDependent = true; 4892 return DeclPtrTy(); 4893 } 4894 4895 // A tag 'foo::bar' must already exist. 4896 Diag(NameLoc, diag::err_not_tag_in_scope) 4897 << Kind << Name << DC << SS.getRange(); 4898 Name = 0; 4899 Invalid = true; 4900 goto CreateNewDecl; 4901 } 4902 } else if (Name) { 4903 // If this is a named struct, check to see if there was a previous forward 4904 // declaration or definition. 4905 // FIXME: We're looking into outer scopes here, even when we 4906 // shouldn't be. Doing so can result in ambiguities that we 4907 // shouldn't be diagnosing. 4908 LookupName(Previous, S); 4909 4910 // Note: there used to be some attempt at recovery here. 4911 if (Previous.isAmbiguous()) 4912 return DeclPtrTy(); 4913 4914 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4915 // FIXME: This makes sure that we ignore the contexts associated 4916 // with C structs, unions, and enums when looking for a matching 4917 // tag declaration or definition. See the similar lookup tweak 4918 // in Sema::LookupName; is there a better way to deal with this? 4919 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4920 SearchDC = SearchDC->getParent(); 4921 } 4922 } 4923 4924 if (Previous.isSingleResult() && 4925 Previous.getFoundDecl()->isTemplateParameter()) { 4926 // Maybe we will complain about the shadowed template parameter. 4927 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4928 // Just pretend that we didn't see the previous declaration. 4929 Previous.clear(); 4930 } 4931 4932 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4933 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4934 // This is a declaration of or a reference to "std::bad_alloc". 4935 isStdBadAlloc = true; 4936 4937 if (Previous.empty() && StdBadAlloc) { 4938 // std::bad_alloc has been implicitly declared (but made invisible to 4939 // name lookup). Fill in this implicit declaration as the previous 4940 // declaration, so that the declarations get chained appropriately. 4941 Previous.addDecl(StdBadAlloc); 4942 } 4943 } 4944 4945 // If we didn't find a previous declaration, and this is a reference 4946 // (or friend reference), move to the correct scope. In C++, we 4947 // also need to do a redeclaration lookup there, just in case 4948 // there's a shadow friend decl. 4949 if (Name && Previous.empty() && 4950 (TUK == TUK_Reference || TUK == TUK_Friend)) { 4951 if (Invalid) goto CreateNewDecl; 4952 assert(SS.isEmpty()); 4953 4954 if (TUK == TUK_Reference) { 4955 // C++ [basic.scope.pdecl]p5: 4956 // -- for an elaborated-type-specifier of the form 4957 // 4958 // class-key identifier 4959 // 4960 // if the elaborated-type-specifier is used in the 4961 // decl-specifier-seq or parameter-declaration-clause of a 4962 // function defined in namespace scope, the identifier is 4963 // declared as a class-name in the namespace that contains 4964 // the declaration; otherwise, except as a friend 4965 // declaration, the identifier is declared in the smallest 4966 // non-class, non-function-prototype scope that contains the 4967 // declaration. 4968 // 4969 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4970 // C structs and unions. 4971 // 4972 // It is an error in C++ to declare (rather than define) an enum 4973 // type, including via an elaborated type specifier. We'll 4974 // diagnose that later; for now, declare the enum in the same 4975 // scope as we would have picked for any other tag type. 4976 // 4977 // GNU C also supports this behavior as part of its incomplete 4978 // enum types extension, while GNU C++ does not. 4979 // 4980 // Find the context where we'll be declaring the tag. 4981 // FIXME: We would like to maintain the current DeclContext as the 4982 // lexical context, 4983 while (SearchDC->isRecord()) 4984 SearchDC = SearchDC->getParent(); 4985 4986 // Find the scope where we'll be declaring the tag. 4987 while (S->isClassScope() || 4988 (getLangOptions().CPlusPlus && 4989 S->isFunctionPrototypeScope()) || 4990 ((S->getFlags() & Scope::DeclScope) == 0) || 4991 (S->getEntity() && 4992 ((DeclContext *)S->getEntity())->isTransparentContext())) 4993 S = S->getParent(); 4994 } else { 4995 assert(TUK == TUK_Friend); 4996 // C++ [namespace.memdef]p3: 4997 // If a friend declaration in a non-local class first declares a 4998 // class or function, the friend class or function is a member of 4999 // the innermost enclosing namespace. 5000 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5001 } 5002 5003 // In C++, look for a shadow friend decl. 5004 if (getLangOptions().CPlusPlus) { 5005 Previous.setRedeclarationKind(ForRedeclaration); 5006 LookupQualifiedName(Previous, SearchDC); 5007 } 5008 } 5009 5010 if (!Previous.empty()) { 5011 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5012 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5013 // If this is a use of a previous tag, or if the tag is already declared 5014 // in the same scope (so that the definition/declaration completes or 5015 // rementions the tag), reuse the decl. 5016 if (TUK == TUK_Reference || TUK == TUK_Friend || 5017 isDeclInScope(PrevDecl, SearchDC, S)) { 5018 // Make sure that this wasn't declared as an enum and now used as a 5019 // struct or something similar. 5020 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5021 bool SafeToContinue 5022 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 5023 Kind != TagDecl::TK_enum); 5024 if (SafeToContinue) 5025 Diag(KWLoc, diag::err_use_with_wrong_tag) 5026 << Name 5027 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5028 PrevTagDecl->getKindName()); 5029 else 5030 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5031 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5032 5033 if (SafeToContinue) 5034 Kind = PrevTagDecl->getTagKind(); 5035 else { 5036 // Recover by making this an anonymous redefinition. 5037 Name = 0; 5038 Previous.clear(); 5039 Invalid = true; 5040 } 5041 } 5042 5043 if (!Invalid) { 5044 // If this is a use, just return the declaration we found. 5045 5046 // FIXME: In the future, return a variant or some other clue 5047 // for the consumer of this Decl to know it doesn't own it. 5048 // For our current ASTs this shouldn't be a problem, but will 5049 // need to be changed with DeclGroups. 5050 if (TUK == TUK_Reference || TUK == TUK_Friend) 5051 return DeclPtrTy::make(PrevTagDecl); 5052 5053 // Diagnose attempts to redefine a tag. 5054 if (TUK == TUK_Definition) { 5055 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5056 // If we're defining a specialization and the previous definition 5057 // is from an implicit instantiation, don't emit an error 5058 // here; we'll catch this in the general case below. 5059 if (!isExplicitSpecialization || 5060 !isa<CXXRecordDecl>(Def) || 5061 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5062 == TSK_ExplicitSpecialization) { 5063 Diag(NameLoc, diag::err_redefinition) << Name; 5064 Diag(Def->getLocation(), diag::note_previous_definition); 5065 // If this is a redefinition, recover by making this 5066 // struct be anonymous, which will make any later 5067 // references get the previous definition. 5068 Name = 0; 5069 Previous.clear(); 5070 Invalid = true; 5071 } 5072 } else { 5073 // If the type is currently being defined, complain 5074 // about a nested redefinition. 5075 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5076 if (Tag->isBeingDefined()) { 5077 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5078 Diag(PrevTagDecl->getLocation(), 5079 diag::note_previous_definition); 5080 Name = 0; 5081 Previous.clear(); 5082 Invalid = true; 5083 } 5084 } 5085 5086 // Okay, this is definition of a previously declared or referenced 5087 // tag PrevDecl. We're going to create a new Decl for it. 5088 } 5089 } 5090 // If we get here we have (another) forward declaration or we 5091 // have a definition. Just create a new decl. 5092 5093 } else { 5094 // If we get here, this is a definition of a new tag type in a nested 5095 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5096 // new decl/type. We set PrevDecl to NULL so that the entities 5097 // have distinct types. 5098 Previous.clear(); 5099 } 5100 // If we get here, we're going to create a new Decl. If PrevDecl 5101 // is non-NULL, it's a definition of the tag declared by 5102 // PrevDecl. If it's NULL, we have a new definition. 5103 } else { 5104 // PrevDecl is a namespace, template, or anything else 5105 // that lives in the IDNS_Tag identifier namespace. 5106 if (TUK == TUK_Reference || TUK == TUK_Friend || 5107 isDeclInScope(PrevDecl, SearchDC, S)) { 5108 // The tag name clashes with a namespace name, issue an error and 5109 // recover by making this tag be anonymous. 5110 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5111 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5112 Name = 0; 5113 Previous.clear(); 5114 Invalid = true; 5115 } else { 5116 // The existing declaration isn't relevant to us; we're in a 5117 // new scope, so clear out the previous declaration. 5118 Previous.clear(); 5119 } 5120 } 5121 } 5122 5123CreateNewDecl: 5124 5125 TagDecl *PrevDecl = 0; 5126 if (Previous.isSingleResult()) 5127 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5128 5129 // If there is an identifier, use the location of the identifier as the 5130 // location of the decl, otherwise use the location of the struct/union 5131 // keyword. 5132 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5133 5134 // Otherwise, create a new declaration. If there is a previous 5135 // declaration of the same entity, the two will be linked via 5136 // PrevDecl. 5137 TagDecl *New; 5138 5139 if (Kind == TagDecl::TK_enum) { 5140 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5141 // enum X { A, B, C } D; D should chain to X. 5142 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5143 cast_or_null<EnumDecl>(PrevDecl)); 5144 // If this is an undefined enum, warn. 5145 if (TUK != TUK_Definition && !Invalid) { 5146 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5147 : diag::ext_forward_ref_enum; 5148 Diag(Loc, DK); 5149 } 5150 } else { 5151 // struct/union/class 5152 5153 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5154 // struct X { int A; } D; D should chain to X. 5155 if (getLangOptions().CPlusPlus) { 5156 // FIXME: Look for a way to use RecordDecl for simple structs. 5157 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5158 cast_or_null<CXXRecordDecl>(PrevDecl)); 5159 5160 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5161 StdBadAlloc = cast<CXXRecordDecl>(New); 5162 } else 5163 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5164 cast_or_null<RecordDecl>(PrevDecl)); 5165 } 5166 5167 // Maybe add qualifier info. 5168 if (SS.isNotEmpty()) { 5169 NestedNameSpecifier *NNS 5170 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5171 New->setQualifierInfo(NNS, SS.getRange()); 5172 } 5173 5174 if (Kind != TagDecl::TK_enum) { 5175 // Handle #pragma pack: if the #pragma pack stack has non-default 5176 // alignment, make up a packed attribute for this decl. These 5177 // attributes are checked when the ASTContext lays out the 5178 // structure. 5179 // 5180 // It is important for implementing the correct semantics that this 5181 // happen here (in act on tag decl). The #pragma pack stack is 5182 // maintained as a result of parser callbacks which can occur at 5183 // many points during the parsing of a struct declaration (because 5184 // the #pragma tokens are effectively skipped over during the 5185 // parsing of the struct). 5186 if (unsigned Alignment = getPragmaPackAlignment()) 5187 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5188 } 5189 5190 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5191 // C++ [dcl.typedef]p3: 5192 // [...] Similarly, in a given scope, a class or enumeration 5193 // shall not be declared with the same name as a typedef-name 5194 // that is declared in that scope and refers to a type other 5195 // than the class or enumeration itself. 5196 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5197 ForRedeclaration); 5198 LookupName(Lookup, S); 5199 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5200 NamedDecl *PrevTypedefNamed = PrevTypedef; 5201 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5202 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5203 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5204 Diag(Loc, diag::err_tag_definition_of_typedef) 5205 << Context.getTypeDeclType(New) 5206 << PrevTypedef->getUnderlyingType(); 5207 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5208 Invalid = true; 5209 } 5210 } 5211 5212 // If this is a specialization of a member class (of a class template), 5213 // check the specialization. 5214 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5215 Invalid = true; 5216 5217 if (Invalid) 5218 New->setInvalidDecl(); 5219 5220 if (Attr) 5221 ProcessDeclAttributeList(S, New, Attr); 5222 5223 // If we're declaring or defining a tag in function prototype scope 5224 // in C, note that this type can only be used within the function. 5225 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5226 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5227 5228 // Set the lexical context. If the tag has a C++ scope specifier, the 5229 // lexical context will be different from the semantic context. 5230 New->setLexicalDeclContext(CurContext); 5231 5232 // Mark this as a friend decl if applicable. 5233 if (TUK == TUK_Friend) 5234 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5235 5236 // Set the access specifier. 5237 if (!Invalid && SearchDC->isRecord()) 5238 SetMemberAccessSpecifier(New, PrevDecl, AS); 5239 5240 if (TUK == TUK_Definition) 5241 New->startDefinition(); 5242 5243 // If this has an identifier, add it to the scope stack. 5244 if (TUK == TUK_Friend) { 5245 // We might be replacing an existing declaration in the lookup tables; 5246 // if so, borrow its access specifier. 5247 if (PrevDecl) 5248 New->setAccess(PrevDecl->getAccess()); 5249 5250 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5251 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5252 if (Name) // can be null along some error paths 5253 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5254 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5255 } else if (Name) { 5256 S = getNonFieldDeclScope(S); 5257 PushOnScopeChains(New, S); 5258 } else { 5259 CurContext->addDecl(New); 5260 } 5261 5262 // If this is the C FILE type, notify the AST context. 5263 if (IdentifierInfo *II = New->getIdentifier()) 5264 if (!New->isInvalidDecl() && 5265 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5266 II->isStr("FILE")) 5267 Context.setFILEDecl(New); 5268 5269 OwnedDecl = true; 5270 return DeclPtrTy::make(New); 5271} 5272 5273void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5274 AdjustDeclIfTemplate(TagD); 5275 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5276 5277 // Enter the tag context. 5278 PushDeclContext(S, Tag); 5279} 5280 5281void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5282 SourceLocation LBraceLoc) { 5283 AdjustDeclIfTemplate(TagD); 5284 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5285 5286 FieldCollector->StartClass(); 5287 5288 if (!Record->getIdentifier()) 5289 return; 5290 5291 // C++ [class]p2: 5292 // [...] The class-name is also inserted into the scope of the 5293 // class itself; this is known as the injected-class-name. For 5294 // purposes of access checking, the injected-class-name is treated 5295 // as if it were a public member name. 5296 CXXRecordDecl *InjectedClassName 5297 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5298 CurContext, Record->getLocation(), 5299 Record->getIdentifier(), 5300 Record->getTagKeywordLoc(), 5301 Record); 5302 InjectedClassName->setImplicit(); 5303 InjectedClassName->setAccess(AS_public); 5304 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5305 InjectedClassName->setDescribedClassTemplate(Template); 5306 PushOnScopeChains(InjectedClassName, S); 5307 assert(InjectedClassName->isInjectedClassName() && 5308 "Broken injected-class-name"); 5309} 5310 5311// Traverses the class and any nested classes, making a note of any 5312// dynamic classes that have no key function so that we can mark all of 5313// their virtual member functions as "used" at the end of the translation 5314// unit. This ensures that all functions needed by the vtable will get 5315// instantiated/synthesized. 5316static void 5317RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5318 SourceLocation Loc) { 5319 // We don't look at dependent or undefined classes. 5320 if (Record->isDependentContext() || !Record->isDefinition()) 5321 return; 5322 5323 if (Record->isDynamicClass()) { 5324 const CXXMethodDecl *KeyFunction = S.Context.getKeyFunction(Record); 5325 5326 if (!KeyFunction) 5327 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, 5328 Loc)); 5329 5330 if ((!KeyFunction || (KeyFunction->getBody() && KeyFunction->isInlined())) 5331 && Record->getLinkage() == ExternalLinkage) 5332 S.Diag(Record->getLocation(), diag::warn_weak_vtable) << Record; 5333 } 5334 for (DeclContext::decl_iterator D = Record->decls_begin(), 5335 DEnd = Record->decls_end(); 5336 D != DEnd; ++D) { 5337 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5338 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5339 } 5340} 5341 5342void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5343 SourceLocation RBraceLoc) { 5344 AdjustDeclIfTemplate(TagD); 5345 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5346 Tag->setRBraceLoc(RBraceLoc); 5347 5348 if (isa<CXXRecordDecl>(Tag)) 5349 FieldCollector->FinishClass(); 5350 5351 // Exit this scope of this tag's definition. 5352 PopDeclContext(); 5353 5354 if (isa<CXXRecordDecl>(Tag) && !Tag->getLexicalDeclContext()->isRecord()) 5355 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5356 RBraceLoc); 5357 5358 // Notify the consumer that we've defined a tag. 5359 Consumer.HandleTagDeclDefinition(Tag); 5360} 5361 5362void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5363 AdjustDeclIfTemplate(TagD); 5364 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5365 Tag->setInvalidDecl(); 5366 5367 // We're undoing ActOnTagStartDefinition here, not 5368 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5369 // the FieldCollector. 5370 5371 PopDeclContext(); 5372} 5373 5374// Note that FieldName may be null for anonymous bitfields. 5375bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5376 QualType FieldTy, const Expr *BitWidth, 5377 bool *ZeroWidth) { 5378 // Default to true; that shouldn't confuse checks for emptiness 5379 if (ZeroWidth) 5380 *ZeroWidth = true; 5381 5382 // C99 6.7.2.1p4 - verify the field type. 5383 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5384 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5385 // Handle incomplete types with specific error. 5386 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5387 return true; 5388 if (FieldName) 5389 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5390 << FieldName << FieldTy << BitWidth->getSourceRange(); 5391 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5392 << FieldTy << BitWidth->getSourceRange(); 5393 } 5394 5395 // If the bit-width is type- or value-dependent, don't try to check 5396 // it now. 5397 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5398 return false; 5399 5400 llvm::APSInt Value; 5401 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5402 return true; 5403 5404 if (Value != 0 && ZeroWidth) 5405 *ZeroWidth = false; 5406 5407 // Zero-width bitfield is ok for anonymous field. 5408 if (Value == 0 && FieldName) 5409 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5410 5411 if (Value.isSigned() && Value.isNegative()) { 5412 if (FieldName) 5413 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5414 << FieldName << Value.toString(10); 5415 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5416 << Value.toString(10); 5417 } 5418 5419 if (!FieldTy->isDependentType()) { 5420 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5421 if (Value.getZExtValue() > TypeSize) { 5422 if (!getLangOptions().CPlusPlus) { 5423 if (FieldName) 5424 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5425 << FieldName << (unsigned)Value.getZExtValue() 5426 << (unsigned)TypeSize; 5427 5428 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5429 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5430 } 5431 5432 if (FieldName) 5433 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5434 << FieldName << (unsigned)Value.getZExtValue() 5435 << (unsigned)TypeSize; 5436 else 5437 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5438 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5439 } 5440 } 5441 5442 return false; 5443} 5444 5445/// ActOnField - Each field of a struct/union/class is passed into this in order 5446/// to create a FieldDecl object for it. 5447Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5448 SourceLocation DeclStart, 5449 Declarator &D, ExprTy *BitfieldWidth) { 5450 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5451 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5452 AS_public); 5453 return DeclPtrTy::make(Res); 5454} 5455 5456/// HandleField - Analyze a field of a C struct or a C++ data member. 5457/// 5458FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5459 SourceLocation DeclStart, 5460 Declarator &D, Expr *BitWidth, 5461 AccessSpecifier AS) { 5462 IdentifierInfo *II = D.getIdentifier(); 5463 SourceLocation Loc = DeclStart; 5464 if (II) Loc = D.getIdentifierLoc(); 5465 5466 TypeSourceInfo *TInfo = 0; 5467 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5468 if (getLangOptions().CPlusPlus) 5469 CheckExtraCXXDefaultArguments(D); 5470 5471 DiagnoseFunctionSpecifiers(D); 5472 5473 if (D.getDeclSpec().isThreadSpecified()) 5474 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5475 5476 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5477 ForRedeclaration); 5478 5479 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5480 // Maybe we will complain about the shadowed template parameter. 5481 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5482 // Just pretend that we didn't see the previous declaration. 5483 PrevDecl = 0; 5484 } 5485 5486 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5487 PrevDecl = 0; 5488 5489 bool Mutable 5490 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5491 SourceLocation TSSL = D.getSourceRange().getBegin(); 5492 FieldDecl *NewFD 5493 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5494 AS, PrevDecl, &D); 5495 5496 if (NewFD->isInvalidDecl()) 5497 Record->setInvalidDecl(); 5498 5499 if (NewFD->isInvalidDecl() && PrevDecl) { 5500 // Don't introduce NewFD into scope; there's already something 5501 // with the same name in the same scope. 5502 } else if (II) { 5503 PushOnScopeChains(NewFD, S); 5504 } else 5505 Record->addDecl(NewFD); 5506 5507 return NewFD; 5508} 5509 5510/// \brief Build a new FieldDecl and check its well-formedness. 5511/// 5512/// This routine builds a new FieldDecl given the fields name, type, 5513/// record, etc. \p PrevDecl should refer to any previous declaration 5514/// with the same name and in the same scope as the field to be 5515/// created. 5516/// 5517/// \returns a new FieldDecl. 5518/// 5519/// \todo The Declarator argument is a hack. It will be removed once 5520FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5521 TypeSourceInfo *TInfo, 5522 RecordDecl *Record, SourceLocation Loc, 5523 bool Mutable, Expr *BitWidth, 5524 SourceLocation TSSL, 5525 AccessSpecifier AS, NamedDecl *PrevDecl, 5526 Declarator *D) { 5527 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5528 bool InvalidDecl = false; 5529 if (D) InvalidDecl = D->isInvalidType(); 5530 5531 // If we receive a broken type, recover by assuming 'int' and 5532 // marking this declaration as invalid. 5533 if (T.isNull()) { 5534 InvalidDecl = true; 5535 T = Context.IntTy; 5536 } 5537 5538 QualType EltTy = Context.getBaseElementType(T); 5539 if (!EltTy->isDependentType() && 5540 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5541 InvalidDecl = true; 5542 5543 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5544 // than a variably modified type. 5545 if (!InvalidDecl && T->isVariablyModifiedType()) { 5546 bool SizeIsNegative; 5547 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5548 SizeIsNegative); 5549 if (!FixedTy.isNull()) { 5550 Diag(Loc, diag::warn_illegal_constant_array_size); 5551 T = FixedTy; 5552 } else { 5553 if (SizeIsNegative) 5554 Diag(Loc, diag::err_typecheck_negative_array_size); 5555 else 5556 Diag(Loc, diag::err_typecheck_field_variable_size); 5557 InvalidDecl = true; 5558 } 5559 } 5560 5561 // Fields can not have abstract class types 5562 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5563 diag::err_abstract_type_in_decl, 5564 AbstractFieldType)) 5565 InvalidDecl = true; 5566 5567 bool ZeroWidth = false; 5568 // If this is declared as a bit-field, check the bit-field. 5569 if (!InvalidDecl && BitWidth && 5570 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5571 InvalidDecl = true; 5572 DeleteExpr(BitWidth); 5573 BitWidth = 0; 5574 ZeroWidth = false; 5575 } 5576 5577 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5578 BitWidth, Mutable); 5579 if (InvalidDecl) 5580 NewFD->setInvalidDecl(); 5581 5582 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5583 Diag(Loc, diag::err_duplicate_member) << II; 5584 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5585 NewFD->setInvalidDecl(); 5586 } 5587 5588 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5589 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5590 5591 if (!T->isPODType()) 5592 CXXRecord->setPOD(false); 5593 if (!ZeroWidth) 5594 CXXRecord->setEmpty(false); 5595 5596 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5597 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5598 5599 if (!RDecl->hasTrivialConstructor()) 5600 CXXRecord->setHasTrivialConstructor(false); 5601 if (!RDecl->hasTrivialCopyConstructor()) 5602 CXXRecord->setHasTrivialCopyConstructor(false); 5603 if (!RDecl->hasTrivialCopyAssignment()) 5604 CXXRecord->setHasTrivialCopyAssignment(false); 5605 if (!RDecl->hasTrivialDestructor()) 5606 CXXRecord->setHasTrivialDestructor(false); 5607 5608 // C++ 9.5p1: An object of a class with a non-trivial 5609 // constructor, a non-trivial copy constructor, a non-trivial 5610 // destructor, or a non-trivial copy assignment operator 5611 // cannot be a member of a union, nor can an array of such 5612 // objects. 5613 // TODO: C++0x alters this restriction significantly. 5614 if (Record->isUnion()) { 5615 // We check for copy constructors before constructors 5616 // because otherwise we'll never get complaints about 5617 // copy constructors. 5618 5619 CXXSpecialMember member = CXXInvalid; 5620 if (!RDecl->hasTrivialCopyConstructor()) 5621 member = CXXCopyConstructor; 5622 else if (!RDecl->hasTrivialConstructor()) 5623 member = CXXConstructor; 5624 else if (!RDecl->hasTrivialCopyAssignment()) 5625 member = CXXCopyAssignment; 5626 else if (!RDecl->hasTrivialDestructor()) 5627 member = CXXDestructor; 5628 5629 if (member != CXXInvalid) { 5630 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5631 DiagnoseNontrivial(RT, member); 5632 NewFD->setInvalidDecl(); 5633 } 5634 } 5635 } 5636 } 5637 5638 // FIXME: We need to pass in the attributes given an AST 5639 // representation, not a parser representation. 5640 if (D) 5641 // FIXME: What to pass instead of TUScope? 5642 ProcessDeclAttributes(TUScope, NewFD, *D); 5643 5644 if (T.isObjCGCWeak()) 5645 Diag(Loc, diag::warn_attribute_weak_on_field); 5646 5647 NewFD->setAccess(AS); 5648 5649 // C++ [dcl.init.aggr]p1: 5650 // An aggregate is an array or a class (clause 9) with [...] no 5651 // private or protected non-static data members (clause 11). 5652 // A POD must be an aggregate. 5653 if (getLangOptions().CPlusPlus && 5654 (AS == AS_private || AS == AS_protected)) { 5655 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5656 CXXRecord->setAggregate(false); 5657 CXXRecord->setPOD(false); 5658 } 5659 5660 return NewFD; 5661} 5662 5663/// DiagnoseNontrivial - Given that a class has a non-trivial 5664/// special member, figure out why. 5665void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5666 QualType QT(T, 0U); 5667 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5668 5669 // Check whether the member was user-declared. 5670 switch (member) { 5671 case CXXInvalid: 5672 break; 5673 5674 case CXXConstructor: 5675 if (RD->hasUserDeclaredConstructor()) { 5676 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5677 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5678 const FunctionDecl *body = 0; 5679 ci->getBody(body); 5680 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5681 SourceLocation CtorLoc = ci->getLocation(); 5682 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5683 return; 5684 } 5685 } 5686 5687 assert(0 && "found no user-declared constructors"); 5688 return; 5689 } 5690 break; 5691 5692 case CXXCopyConstructor: 5693 if (RD->hasUserDeclaredCopyConstructor()) { 5694 SourceLocation CtorLoc = 5695 RD->getCopyConstructor(Context, 0)->getLocation(); 5696 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5697 return; 5698 } 5699 break; 5700 5701 case CXXCopyAssignment: 5702 if (RD->hasUserDeclaredCopyAssignment()) { 5703 // FIXME: this should use the location of the copy 5704 // assignment, not the type. 5705 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5706 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5707 return; 5708 } 5709 break; 5710 5711 case CXXDestructor: 5712 if (RD->hasUserDeclaredDestructor()) { 5713 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5714 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5715 return; 5716 } 5717 break; 5718 } 5719 5720 typedef CXXRecordDecl::base_class_iterator base_iter; 5721 5722 // Virtual bases and members inhibit trivial copying/construction, 5723 // but not trivial destruction. 5724 if (member != CXXDestructor) { 5725 // Check for virtual bases. vbases includes indirect virtual bases, 5726 // so we just iterate through the direct bases. 5727 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5728 if (bi->isVirtual()) { 5729 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5730 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5731 return; 5732 } 5733 5734 // Check for virtual methods. 5735 typedef CXXRecordDecl::method_iterator meth_iter; 5736 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5737 ++mi) { 5738 if (mi->isVirtual()) { 5739 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5740 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5741 return; 5742 } 5743 } 5744 } 5745 5746 bool (CXXRecordDecl::*hasTrivial)() const; 5747 switch (member) { 5748 case CXXConstructor: 5749 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5750 case CXXCopyConstructor: 5751 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5752 case CXXCopyAssignment: 5753 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5754 case CXXDestructor: 5755 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5756 default: 5757 assert(0 && "unexpected special member"); return; 5758 } 5759 5760 // Check for nontrivial bases (and recurse). 5761 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5762 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5763 assert(BaseRT && "Don't know how to handle dependent bases"); 5764 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5765 if (!(BaseRecTy->*hasTrivial)()) { 5766 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5767 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5768 DiagnoseNontrivial(BaseRT, member); 5769 return; 5770 } 5771 } 5772 5773 // Check for nontrivial members (and recurse). 5774 typedef RecordDecl::field_iterator field_iter; 5775 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5776 ++fi) { 5777 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5778 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5779 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5780 5781 if (!(EltRD->*hasTrivial)()) { 5782 SourceLocation FLoc = (*fi)->getLocation(); 5783 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5784 DiagnoseNontrivial(EltRT, member); 5785 return; 5786 } 5787 } 5788 } 5789 5790 assert(0 && "found no explanation for non-trivial member"); 5791} 5792 5793/// TranslateIvarVisibility - Translate visibility from a token ID to an 5794/// AST enum value. 5795static ObjCIvarDecl::AccessControl 5796TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5797 switch (ivarVisibility) { 5798 default: assert(0 && "Unknown visitibility kind"); 5799 case tok::objc_private: return ObjCIvarDecl::Private; 5800 case tok::objc_public: return ObjCIvarDecl::Public; 5801 case tok::objc_protected: return ObjCIvarDecl::Protected; 5802 case tok::objc_package: return ObjCIvarDecl::Package; 5803 } 5804} 5805 5806/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5807/// in order to create an IvarDecl object for it. 5808Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5809 SourceLocation DeclStart, 5810 DeclPtrTy IntfDecl, 5811 Declarator &D, ExprTy *BitfieldWidth, 5812 tok::ObjCKeywordKind Visibility) { 5813 5814 IdentifierInfo *II = D.getIdentifier(); 5815 Expr *BitWidth = (Expr*)BitfieldWidth; 5816 SourceLocation Loc = DeclStart; 5817 if (II) Loc = D.getIdentifierLoc(); 5818 5819 // FIXME: Unnamed fields can be handled in various different ways, for 5820 // example, unnamed unions inject all members into the struct namespace! 5821 5822 TypeSourceInfo *TInfo = 0; 5823 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5824 5825 if (BitWidth) { 5826 // 6.7.2.1p3, 6.7.2.1p4 5827 if (VerifyBitField(Loc, II, T, BitWidth)) { 5828 D.setInvalidType(); 5829 DeleteExpr(BitWidth); 5830 BitWidth = 0; 5831 } 5832 } else { 5833 // Not a bitfield. 5834 5835 // validate II. 5836 5837 } 5838 5839 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5840 // than a variably modified type. 5841 if (T->isVariablyModifiedType()) { 5842 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5843 D.setInvalidType(); 5844 } 5845 5846 // Get the visibility (access control) for this ivar. 5847 ObjCIvarDecl::AccessControl ac = 5848 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5849 : ObjCIvarDecl::None; 5850 // Must set ivar's DeclContext to its enclosing interface. 5851 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 5852 ObjCContainerDecl *EnclosingContext; 5853 if (ObjCImplementationDecl *IMPDecl = 5854 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5855 // Case of ivar declared in an implementation. Context is that of its class. 5856 EnclosingContext = IMPDecl->getClassInterface(); 5857 assert(EnclosingContext && "Implementation has no class interface!"); 5858 } else { 5859 if (ObjCCategoryDecl *CDecl = 5860 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 5861 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 5862 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 5863 return DeclPtrTy(); 5864 } 5865 } 5866 EnclosingContext = EnclosingDecl; 5867 } 5868 5869 // Construct the decl. 5870 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5871 EnclosingContext, Loc, II, T, 5872 TInfo, ac, (Expr *)BitfieldWidth); 5873 5874 if (II) { 5875 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5876 ForRedeclaration); 5877 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5878 && !isa<TagDecl>(PrevDecl)) { 5879 Diag(Loc, diag::err_duplicate_member) << II; 5880 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5881 NewID->setInvalidDecl(); 5882 } 5883 } 5884 5885 // Process attributes attached to the ivar. 5886 ProcessDeclAttributes(S, NewID, D); 5887 5888 if (D.isInvalidType()) 5889 NewID->setInvalidDecl(); 5890 5891 if (II) { 5892 // FIXME: When interfaces are DeclContexts, we'll need to add 5893 // these to the interface. 5894 S->AddDecl(DeclPtrTy::make(NewID)); 5895 IdResolver.AddDecl(NewID); 5896 } 5897 5898 return DeclPtrTy::make(NewID); 5899} 5900 5901void Sema::ActOnFields(Scope* S, 5902 SourceLocation RecLoc, DeclPtrTy RecDecl, 5903 DeclPtrTy *Fields, unsigned NumFields, 5904 SourceLocation LBrac, SourceLocation RBrac, 5905 AttributeList *Attr) { 5906 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5907 assert(EnclosingDecl && "missing record or interface decl"); 5908 5909 // If the decl this is being inserted into is invalid, then it may be a 5910 // redeclaration or some other bogus case. Don't try to add fields to it. 5911 if (EnclosingDecl->isInvalidDecl()) { 5912 // FIXME: Deallocate fields? 5913 return; 5914 } 5915 5916 5917 // Verify that all the fields are okay. 5918 unsigned NumNamedMembers = 0; 5919 llvm::SmallVector<FieldDecl*, 32> RecFields; 5920 5921 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5922 for (unsigned i = 0; i != NumFields; ++i) { 5923 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5924 5925 // Get the type for the field. 5926 Type *FDTy = FD->getType().getTypePtr(); 5927 5928 if (!FD->isAnonymousStructOrUnion()) { 5929 // Remember all fields written by the user. 5930 RecFields.push_back(FD); 5931 } 5932 5933 // If the field is already invalid for some reason, don't emit more 5934 // diagnostics about it. 5935 if (FD->isInvalidDecl()) { 5936 EnclosingDecl->setInvalidDecl(); 5937 continue; 5938 } 5939 5940 // C99 6.7.2.1p2: 5941 // A structure or union shall not contain a member with 5942 // incomplete or function type (hence, a structure shall not 5943 // contain an instance of itself, but may contain a pointer to 5944 // an instance of itself), except that the last member of a 5945 // structure with more than one named member may have incomplete 5946 // array type; such a structure (and any union containing, 5947 // possibly recursively, a member that is such a structure) 5948 // shall not be a member of a structure or an element of an 5949 // array. 5950 if (FDTy->isFunctionType()) { 5951 // Field declared as a function. 5952 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5953 << FD->getDeclName(); 5954 FD->setInvalidDecl(); 5955 EnclosingDecl->setInvalidDecl(); 5956 continue; 5957 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5958 Record && Record->isStruct()) { 5959 // Flexible array member. 5960 if (NumNamedMembers < 1) { 5961 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5962 << FD->getDeclName(); 5963 FD->setInvalidDecl(); 5964 EnclosingDecl->setInvalidDecl(); 5965 continue; 5966 } 5967 // Okay, we have a legal flexible array member at the end of the struct. 5968 if (Record) 5969 Record->setHasFlexibleArrayMember(true); 5970 } else if (!FDTy->isDependentType() && 5971 RequireCompleteType(FD->getLocation(), FD->getType(), 5972 diag::err_field_incomplete)) { 5973 // Incomplete type 5974 FD->setInvalidDecl(); 5975 EnclosingDecl->setInvalidDecl(); 5976 continue; 5977 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5978 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5979 // If this is a member of a union, then entire union becomes "flexible". 5980 if (Record && Record->isUnion()) { 5981 Record->setHasFlexibleArrayMember(true); 5982 } else { 5983 // If this is a struct/class and this is not the last element, reject 5984 // it. Note that GCC supports variable sized arrays in the middle of 5985 // structures. 5986 if (i != NumFields-1) 5987 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5988 << FD->getDeclName() << FD->getType(); 5989 else { 5990 // We support flexible arrays at the end of structs in 5991 // other structs as an extension. 5992 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5993 << FD->getDeclName(); 5994 if (Record) 5995 Record->setHasFlexibleArrayMember(true); 5996 } 5997 } 5998 } 5999 if (Record && FDTTy->getDecl()->hasObjectMember()) 6000 Record->setHasObjectMember(true); 6001 } else if (FDTy->isObjCInterfaceType()) { 6002 /// A field cannot be an Objective-c object 6003 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6004 FD->setInvalidDecl(); 6005 EnclosingDecl->setInvalidDecl(); 6006 continue; 6007 } else if (getLangOptions().ObjC1 && 6008 getLangOptions().getGCMode() != LangOptions::NonGC && 6009 Record && 6010 (FD->getType()->isObjCObjectPointerType() || 6011 FD->getType().isObjCGCStrong())) 6012 Record->setHasObjectMember(true); 6013 // Keep track of the number of named members. 6014 if (FD->getIdentifier()) 6015 ++NumNamedMembers; 6016 } 6017 6018 // Okay, we successfully defined 'Record'. 6019 if (Record) { 6020 Record->completeDefinition(); 6021 } else { 6022 ObjCIvarDecl **ClsFields = 6023 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6024 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6025 ID->setLocEnd(RBrac); 6026 // Add ivar's to class's DeclContext. 6027 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6028 ClsFields[i]->setLexicalDeclContext(ID); 6029 ID->addDecl(ClsFields[i]); 6030 } 6031 // Must enforce the rule that ivars in the base classes may not be 6032 // duplicates. 6033 if (ID->getSuperClass()) 6034 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6035 } else if (ObjCImplementationDecl *IMPDecl = 6036 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6037 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6038 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6039 // Ivar declared in @implementation never belongs to the implementation. 6040 // Only it is in implementation's lexical context. 6041 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6042 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6043 } else if (ObjCCategoryDecl *CDecl = 6044 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6045 // case of ivars in class extension; all other cases have been 6046 // reported as errors elsewhere. 6047 // FIXME. Class extension does not have a LocEnd field. 6048 // CDecl->setLocEnd(RBrac); 6049 // Add ivar's to class extension's DeclContext. 6050 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6051 ClsFields[i]->setLexicalDeclContext(CDecl); 6052 CDecl->addDecl(ClsFields[i]); 6053 } 6054 } 6055 } 6056 6057 if (Attr) 6058 ProcessDeclAttributeList(S, Record, Attr); 6059} 6060 6061/// \brief Determine whether the given integral value is representable within 6062/// the given type T. 6063static bool isRepresentableIntegerValue(ASTContext &Context, 6064 llvm::APSInt &Value, 6065 QualType T) { 6066 assert(T->isIntegralType() && "Integral type required!"); 6067 unsigned BitWidth = Context.getIntWidth(T); 6068 6069 if (Value.isUnsigned() || Value.isNonNegative()) 6070 return Value.getActiveBits() < BitWidth; 6071 6072 return Value.getMinSignedBits() <= BitWidth; 6073} 6074 6075// \brief Given an integral type, return the next larger integral type 6076// (or a NULL type of no such type exists). 6077static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6078 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6079 // enum checking below. 6080 assert(T->isIntegralType() && "Integral type required!"); 6081 const unsigned NumTypes = 4; 6082 QualType SignedIntegralTypes[NumTypes] = { 6083 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6084 }; 6085 QualType UnsignedIntegralTypes[NumTypes] = { 6086 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6087 Context.UnsignedLongLongTy 6088 }; 6089 6090 unsigned BitWidth = Context.getTypeSize(T); 6091 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6092 : UnsignedIntegralTypes; 6093 for (unsigned I = 0; I != NumTypes; ++I) 6094 if (Context.getTypeSize(Types[I]) > BitWidth) 6095 return Types[I]; 6096 6097 return QualType(); 6098} 6099 6100EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6101 EnumConstantDecl *LastEnumConst, 6102 SourceLocation IdLoc, 6103 IdentifierInfo *Id, 6104 ExprArg val) { 6105 Expr *Val = (Expr *)val.get(); 6106 6107 unsigned IntWidth = Context.Target.getIntWidth(); 6108 llvm::APSInt EnumVal(IntWidth); 6109 QualType EltTy; 6110 if (Val) { 6111 if (Enum->isDependentType() || Val->isTypeDependent()) 6112 EltTy = Context.DependentTy; 6113 else { 6114 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6115 SourceLocation ExpLoc; 6116 if (!Val->isValueDependent() && 6117 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6118 Val = 0; 6119 } else { 6120 if (!getLangOptions().CPlusPlus) { 6121 // C99 6.7.2.2p2: 6122 // The expression that defines the value of an enumeration constant 6123 // shall be an integer constant expression that has a value 6124 // representable as an int. 6125 6126 // Complain if the value is not representable in an int. 6127 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6128 Diag(IdLoc, diag::ext_enum_value_not_int) 6129 << EnumVal.toString(10) << Val->getSourceRange() 6130 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6131 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6132 // Force the type of the expression to 'int'. 6133 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6134 6135 if (Val != val.get()) { 6136 val.release(); 6137 val = Val; 6138 } 6139 } 6140 } 6141 6142 // C++0x [dcl.enum]p5: 6143 // If the underlying type is not fixed, the type of each enumerator 6144 // is the type of its initializing value: 6145 // - If an initializer is specified for an enumerator, the 6146 // initializing value has the same type as the expression. 6147 EltTy = Val->getType(); 6148 } 6149 } 6150 } 6151 6152 if (!Val) { 6153 if (Enum->isDependentType()) 6154 EltTy = Context.DependentTy; 6155 else if (!LastEnumConst) { 6156 // C++0x [dcl.enum]p5: 6157 // If the underlying type is not fixed, the type of each enumerator 6158 // is the type of its initializing value: 6159 // - If no initializer is specified for the first enumerator, the 6160 // initializing value has an unspecified integral type. 6161 // 6162 // GCC uses 'int' for its unspecified integral type, as does 6163 // C99 6.7.2.2p3. 6164 EltTy = Context.IntTy; 6165 } else { 6166 // Assign the last value + 1. 6167 EnumVal = LastEnumConst->getInitVal(); 6168 ++EnumVal; 6169 EltTy = LastEnumConst->getType(); 6170 6171 // Check for overflow on increment. 6172 if (EnumVal < LastEnumConst->getInitVal()) { 6173 // C++0x [dcl.enum]p5: 6174 // If the underlying type is not fixed, the type of each enumerator 6175 // is the type of its initializing value: 6176 // 6177 // - Otherwise the type of the initializing value is the same as 6178 // the type of the initializing value of the preceding enumerator 6179 // unless the incremented value is not representable in that type, 6180 // in which case the type is an unspecified integral type 6181 // sufficient to contain the incremented value. If no such type 6182 // exists, the program is ill-formed. 6183 QualType T = getNextLargerIntegralType(Context, EltTy); 6184 if (T.isNull()) { 6185 // There is no integral type larger enough to represent this 6186 // value. Complain, then allow the value to wrap around. 6187 EnumVal = LastEnumConst->getInitVal(); 6188 EnumVal.zext(EnumVal.getBitWidth() * 2); 6189 Diag(IdLoc, diag::warn_enumerator_too_large) 6190 << EnumVal.toString(10); 6191 } else { 6192 EltTy = T; 6193 } 6194 6195 // Retrieve the last enumerator's value, extent that type to the 6196 // type that is supposed to be large enough to represent the incremented 6197 // value, then increment. 6198 EnumVal = LastEnumConst->getInitVal(); 6199 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6200 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6201 ++EnumVal; 6202 6203 // If we're not in C++, diagnose the overflow of enumerator values, 6204 // which in C99 means that the enumerator value is not representable in 6205 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6206 // permits enumerator values that are representable in some larger 6207 // integral type. 6208 if (!getLangOptions().CPlusPlus && !T.isNull()) 6209 Diag(IdLoc, diag::warn_enum_value_overflow); 6210 } else if (!getLangOptions().CPlusPlus && 6211 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6212 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6213 Diag(IdLoc, diag::ext_enum_value_not_int) 6214 << EnumVal.toString(10) << 1; 6215 } 6216 } 6217 } 6218 6219 if (!EltTy->isDependentType()) { 6220 // Make the enumerator value match the signedness and size of the 6221 // enumerator's type. 6222 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6223 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6224 } 6225 6226 val.release(); 6227 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6228 Val, EnumVal); 6229} 6230 6231 6232Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6233 DeclPtrTy lastEnumConst, 6234 SourceLocation IdLoc, 6235 IdentifierInfo *Id, 6236 SourceLocation EqualLoc, ExprTy *val) { 6237 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6238 EnumConstantDecl *LastEnumConst = 6239 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6240 Expr *Val = static_cast<Expr*>(val); 6241 6242 // The scope passed in may not be a decl scope. Zip up the scope tree until 6243 // we find one that is. 6244 S = getNonFieldDeclScope(S); 6245 6246 // Verify that there isn't already something declared with this name in this 6247 // scope. 6248 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6249 ForRedeclaration); 6250 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6251 // Maybe we will complain about the shadowed template parameter. 6252 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6253 // Just pretend that we didn't see the previous declaration. 6254 PrevDecl = 0; 6255 } 6256 6257 if (PrevDecl) { 6258 // When in C++, we may get a TagDecl with the same name; in this case the 6259 // enum constant will 'hide' the tag. 6260 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6261 "Received TagDecl when not in C++!"); 6262 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6263 if (isa<EnumConstantDecl>(PrevDecl)) 6264 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6265 else 6266 Diag(IdLoc, diag::err_redefinition) << Id; 6267 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6268 if (Val) Val->Destroy(Context); 6269 return DeclPtrTy(); 6270 } 6271 } 6272 6273 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6274 IdLoc, Id, Owned(Val)); 6275 6276 // Register this decl in the current scope stack. 6277 if (New) { 6278 New->setAccess(TheEnumDecl->getAccess()); 6279 PushOnScopeChains(New, S); 6280 } 6281 6282 return DeclPtrTy::make(New); 6283} 6284 6285void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6286 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6287 DeclPtrTy *Elements, unsigned NumElements, 6288 Scope *S, AttributeList *Attr) { 6289 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6290 QualType EnumType = Context.getTypeDeclType(Enum); 6291 6292 if (Attr) 6293 ProcessDeclAttributeList(S, Enum, Attr); 6294 6295 if (Enum->isDependentType()) { 6296 for (unsigned i = 0; i != NumElements; ++i) { 6297 EnumConstantDecl *ECD = 6298 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6299 if (!ECD) continue; 6300 6301 ECD->setType(EnumType); 6302 } 6303 6304 Enum->completeDefinition(Context.DependentTy, Context.DependentTy); 6305 return; 6306 } 6307 6308 // TODO: If the result value doesn't fit in an int, it must be a long or long 6309 // long value. ISO C does not support this, but GCC does as an extension, 6310 // emit a warning. 6311 unsigned IntWidth = Context.Target.getIntWidth(); 6312 unsigned CharWidth = Context.Target.getCharWidth(); 6313 unsigned ShortWidth = Context.Target.getShortWidth(); 6314 6315 // Verify that all the values are okay, compute the size of the values, and 6316 // reverse the list. 6317 unsigned NumNegativeBits = 0; 6318 unsigned NumPositiveBits = 0; 6319 6320 // Keep track of whether all elements have type int. 6321 bool AllElementsInt = true; 6322 6323 for (unsigned i = 0; i != NumElements; ++i) { 6324 EnumConstantDecl *ECD = 6325 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6326 if (!ECD) continue; // Already issued a diagnostic. 6327 6328 const llvm::APSInt &InitVal = ECD->getInitVal(); 6329 6330 // Keep track of the size of positive and negative values. 6331 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6332 NumPositiveBits = std::max(NumPositiveBits, 6333 (unsigned)InitVal.getActiveBits()); 6334 else 6335 NumNegativeBits = std::max(NumNegativeBits, 6336 (unsigned)InitVal.getMinSignedBits()); 6337 6338 // Keep track of whether every enum element has type int (very commmon). 6339 if (AllElementsInt) 6340 AllElementsInt = ECD->getType() == Context.IntTy; 6341 } 6342 6343 // Figure out the type that should be used for this enum. 6344 // FIXME: Support -fshort-enums. 6345 QualType BestType; 6346 unsigned BestWidth; 6347 6348 // C++0x N3000 [conv.prom]p3: 6349 // An rvalue of an unscoped enumeration type whose underlying 6350 // type is not fixed can be converted to an rvalue of the first 6351 // of the following types that can represent all the values of 6352 // the enumeration: int, unsigned int, long int, unsigned long 6353 // int, long long int, or unsigned long long int. 6354 // C99 6.4.4.3p2: 6355 // An identifier declared as an enumeration constant has type int. 6356 // The C99 rule is modified by a gcc extension 6357 QualType BestPromotionType; 6358 6359 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6360 6361 if (NumNegativeBits) { 6362 // If there is a negative value, figure out the smallest integer type (of 6363 // int/long/longlong) that fits. 6364 // If it's packed, check also if it fits a char or a short. 6365 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6366 BestType = Context.SignedCharTy; 6367 BestWidth = CharWidth; 6368 } else if (Packed && NumNegativeBits <= ShortWidth && 6369 NumPositiveBits < ShortWidth) { 6370 BestType = Context.ShortTy; 6371 BestWidth = ShortWidth; 6372 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6373 BestType = Context.IntTy; 6374 BestWidth = IntWidth; 6375 } else { 6376 BestWidth = Context.Target.getLongWidth(); 6377 6378 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6379 BestType = Context.LongTy; 6380 } else { 6381 BestWidth = Context.Target.getLongLongWidth(); 6382 6383 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6384 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6385 BestType = Context.LongLongTy; 6386 } 6387 } 6388 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6389 } else { 6390 // If there is no negative value, figure out the smallest type that fits 6391 // all of the enumerator values. 6392 // If it's packed, check also if it fits a char or a short. 6393 if (Packed && NumPositiveBits <= CharWidth) { 6394 BestType = Context.UnsignedCharTy; 6395 BestPromotionType = Context.IntTy; 6396 BestWidth = CharWidth; 6397 } else if (Packed && NumPositiveBits <= ShortWidth) { 6398 BestType = Context.UnsignedShortTy; 6399 BestPromotionType = Context.IntTy; 6400 BestWidth = ShortWidth; 6401 } else if (NumPositiveBits <= IntWidth) { 6402 BestType = Context.UnsignedIntTy; 6403 BestWidth = IntWidth; 6404 BestPromotionType 6405 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6406 ? Context.UnsignedIntTy : Context.IntTy; 6407 } else if (NumPositiveBits <= 6408 (BestWidth = Context.Target.getLongWidth())) { 6409 BestType = Context.UnsignedLongTy; 6410 BestPromotionType 6411 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6412 ? Context.UnsignedLongTy : Context.LongTy; 6413 } else { 6414 BestWidth = Context.Target.getLongLongWidth(); 6415 assert(NumPositiveBits <= BestWidth && 6416 "How could an initializer get larger than ULL?"); 6417 BestType = Context.UnsignedLongLongTy; 6418 BestPromotionType 6419 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6420 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6421 } 6422 } 6423 6424 // Loop over all of the enumerator constants, changing their types to match 6425 // the type of the enum if needed. 6426 for (unsigned i = 0; i != NumElements; ++i) { 6427 EnumConstantDecl *ECD = 6428 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6429 if (!ECD) continue; // Already issued a diagnostic. 6430 6431 // Standard C says the enumerators have int type, but we allow, as an 6432 // extension, the enumerators to be larger than int size. If each 6433 // enumerator value fits in an int, type it as an int, otherwise type it the 6434 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6435 // that X has type 'int', not 'unsigned'. 6436 6437 // Determine whether the value fits into an int. 6438 llvm::APSInt InitVal = ECD->getInitVal(); 6439 6440 // If it fits into an integer type, force it. Otherwise force it to match 6441 // the enum decl type. 6442 QualType NewTy; 6443 unsigned NewWidth; 6444 bool NewSign; 6445 if (!getLangOptions().CPlusPlus && 6446 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6447 NewTy = Context.IntTy; 6448 NewWidth = IntWidth; 6449 NewSign = true; 6450 } else if (ECD->getType() == BestType) { 6451 // Already the right type! 6452 if (getLangOptions().CPlusPlus) 6453 // C++ [dcl.enum]p4: Following the closing brace of an 6454 // enum-specifier, each enumerator has the type of its 6455 // enumeration. 6456 ECD->setType(EnumType); 6457 continue; 6458 } else { 6459 NewTy = BestType; 6460 NewWidth = BestWidth; 6461 NewSign = BestType->isSignedIntegerType(); 6462 } 6463 6464 // Adjust the APSInt value. 6465 InitVal.extOrTrunc(NewWidth); 6466 InitVal.setIsSigned(NewSign); 6467 ECD->setInitVal(InitVal); 6468 6469 // Adjust the Expr initializer and type. 6470 if (ECD->getInitExpr()) 6471 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6472 CastExpr::CK_IntegralCast, 6473 ECD->getInitExpr(), 6474 /*isLvalue=*/false)); 6475 if (getLangOptions().CPlusPlus) 6476 // C++ [dcl.enum]p4: Following the closing brace of an 6477 // enum-specifier, each enumerator has the type of its 6478 // enumeration. 6479 ECD->setType(EnumType); 6480 else 6481 ECD->setType(NewTy); 6482 } 6483 6484 Enum->completeDefinition(BestType, BestPromotionType); 6485} 6486 6487Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6488 ExprArg expr) { 6489 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6490 6491 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6492 Loc, AsmString); 6493 CurContext->addDecl(New); 6494 return DeclPtrTy::make(New); 6495} 6496 6497void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6498 SourceLocation PragmaLoc, 6499 SourceLocation NameLoc) { 6500 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6501 6502 if (PrevDecl) { 6503 PrevDecl->addAttr(::new (Context) WeakAttr()); 6504 } else { 6505 (void)WeakUndeclaredIdentifiers.insert( 6506 std::pair<IdentifierInfo*,WeakInfo> 6507 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6508 } 6509} 6510 6511void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6512 IdentifierInfo* AliasName, 6513 SourceLocation PragmaLoc, 6514 SourceLocation NameLoc, 6515 SourceLocation AliasNameLoc) { 6516 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6517 LookupOrdinaryName); 6518 WeakInfo W = WeakInfo(Name, NameLoc); 6519 6520 if (PrevDecl) { 6521 if (!PrevDecl->hasAttr<AliasAttr>()) 6522 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6523 DeclApplyPragmaWeak(TUScope, ND, W); 6524 } else { 6525 (void)WeakUndeclaredIdentifiers.insert( 6526 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6527 } 6528} 6529