SemaDecl.cpp revision b21b40532551e946c937bfc2f7584d9195f76c0e
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 return CheckTypenameType(ETK_None, 93 (NestedNameSpecifier *)SS->getScopeRep(), 94 II, SS->getRange()).getAsOpaquePtr(); 95 } 96 97 return 0; 98 } 99 100 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 101 return 0; 102 } 103 104 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 105 // lookup for class-names. 106 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 107 LookupOrdinaryName; 108 LookupResult Result(*this, &II, NameLoc, Kind); 109 if (LookupCtx) { 110 // Perform "qualified" name lookup into the declaration context we 111 // computed, which is either the type of the base of a member access 112 // expression or the declaration context associated with a prior 113 // nested-name-specifier. 114 LookupQualifiedName(Result, LookupCtx); 115 116 if (ObjectTypePtr && Result.empty()) { 117 // C++ [basic.lookup.classref]p3: 118 // If the unqualified-id is ~type-name, the type-name is looked up 119 // in the context of the entire postfix-expression. If the type T of 120 // the object expression is of a class type C, the type-name is also 121 // looked up in the scope of class C. At least one of the lookups shall 122 // find a name that refers to (possibly cv-qualified) T. 123 LookupName(Result, S); 124 } 125 } else { 126 // Perform unqualified name lookup. 127 LookupName(Result, S); 128 } 129 130 NamedDecl *IIDecl = 0; 131 switch (Result.getResultKind()) { 132 case LookupResult::NotFound: 133 case LookupResult::NotFoundInCurrentInstantiation: 134 case LookupResult::FoundOverloaded: 135 case LookupResult::FoundUnresolvedValue: 136 Result.suppressDiagnostics(); 137 return 0; 138 139 case LookupResult::Ambiguous: 140 // Recover from type-hiding ambiguities by hiding the type. We'll 141 // do the lookup again when looking for an object, and we can 142 // diagnose the error then. If we don't do this, then the error 143 // about hiding the type will be immediately followed by an error 144 // that only makes sense if the identifier was treated like a type. 145 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 146 Result.suppressDiagnostics(); 147 return 0; 148 } 149 150 // Look to see if we have a type anywhere in the list of results. 151 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 152 Res != ResEnd; ++Res) { 153 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 154 if (!IIDecl || 155 (*Res)->getLocation().getRawEncoding() < 156 IIDecl->getLocation().getRawEncoding()) 157 IIDecl = *Res; 158 } 159 } 160 161 if (!IIDecl) { 162 // None of the entities we found is a type, so there is no way 163 // to even assume that the result is a type. In this case, don't 164 // complain about the ambiguity. The parser will either try to 165 // perform this lookup again (e.g., as an object name), which 166 // will produce the ambiguity, or will complain that it expected 167 // a type name. 168 Result.suppressDiagnostics(); 169 return 0; 170 } 171 172 // We found a type within the ambiguous lookup; diagnose the 173 // ambiguity and then return that type. This might be the right 174 // answer, or it might not be, but it suppresses any attempt to 175 // perform the name lookup again. 176 break; 177 178 case LookupResult::Found: 179 IIDecl = Result.getFoundDecl(); 180 break; 181 } 182 183 assert(IIDecl && "Didn't find decl"); 184 185 QualType T; 186 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 187 DiagnoseUseOfDecl(IIDecl, NameLoc); 188 189 if (T.isNull()) 190 T = Context.getTypeDeclType(TD); 191 192 if (SS) 193 T = getQualifiedNameType(*SS, T); 194 195 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 196 T = Context.getObjCInterfaceType(IDecl); 197 } else if (UnresolvedUsingTypenameDecl *UUDecl = 198 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 199 // FIXME: preserve source structure information. 200 T = Context.getDependentNameType(ETK_None, 201 UUDecl->getTargetNestedNameSpecifier(), 202 &II); 203 } else { 204 // If it's not plausibly a type, suppress diagnostics. 205 Result.suppressDiagnostics(); 206 return 0; 207 } 208 209 return T.getAsOpaquePtr(); 210} 211 212/// isTagName() - This method is called *for error recovery purposes only* 213/// to determine if the specified name is a valid tag name ("struct foo"). If 214/// so, this returns the TST for the tag corresponding to it (TST_enum, 215/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 216/// where the user forgot to specify the tag. 217DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 218 // Do a tag name lookup in this scope. 219 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 220 LookupName(R, S, false); 221 R.suppressDiagnostics(); 222 if (R.getResultKind() == LookupResult::Found) 223 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 224 switch (TD->getTagKind()) { 225 case TagDecl::TK_struct: return DeclSpec::TST_struct; 226 case TagDecl::TK_union: return DeclSpec::TST_union; 227 case TagDecl::TK_class: return DeclSpec::TST_class; 228 case TagDecl::TK_enum: return DeclSpec::TST_enum; 229 } 230 } 231 232 return DeclSpec::TST_unspecified; 233} 234 235bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 236 SourceLocation IILoc, 237 Scope *S, 238 CXXScopeSpec *SS, 239 TypeTy *&SuggestedType) { 240 // We don't have anything to suggest (yet). 241 SuggestedType = 0; 242 243 // There may have been a typo in the name of the type. Look up typo 244 // results, in case we have something that we can suggest. 245 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 246 NotForRedeclaration); 247 248 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 249 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 250 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 251 !Result->isInvalidDecl()) { 252 // We found a similarly-named type or interface; suggest that. 253 if (!SS || !SS->isSet()) 254 Diag(IILoc, diag::err_unknown_typename_suggest) 255 << &II << Lookup.getLookupName() 256 << FixItHint::CreateReplacement(SourceRange(IILoc), 257 Result->getNameAsString()); 258 else if (DeclContext *DC = computeDeclContext(*SS, false)) 259 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 260 << &II << DC << Lookup.getLookupName() << SS->getRange() 261 << FixItHint::CreateReplacement(SourceRange(IILoc), 262 Result->getNameAsString()); 263 else 264 llvm_unreachable("could not have corrected a typo here"); 265 266 Diag(Result->getLocation(), diag::note_previous_decl) 267 << Result->getDeclName(); 268 269 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 270 return true; 271 } 272 } else if (Lookup.empty()) { 273 // We corrected to a keyword. 274 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 275 Diag(IILoc, diag::err_unknown_typename_suggest) 276 << &II << Corrected; 277 return true; 278 } 279 } 280 281 if (getLangOptions().CPlusPlus) { 282 // See if II is a class template that the user forgot to pass arguments to. 283 UnqualifiedId Name; 284 Name.setIdentifier(&II, IILoc); 285 CXXScopeSpec EmptySS; 286 TemplateTy TemplateResult; 287 if (isTemplateName(S, SS ? *SS : EmptySS, Name, 0, true, TemplateResult) 288 == TNK_Type_template) { 289 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 290 Diag(IILoc, diag::err_template_missing_args) << TplName; 291 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 292 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 293 << TplDecl->getTemplateParameters()->getSourceRange(); 294 } 295 return true; 296 } 297 } 298 299 // FIXME: Should we move the logic that tries to recover from a missing tag 300 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 301 302 if (!SS || (!SS->isSet() && !SS->isInvalid())) 303 Diag(IILoc, diag::err_unknown_typename) << &II; 304 else if (DeclContext *DC = computeDeclContext(*SS, false)) 305 Diag(IILoc, diag::err_typename_nested_not_found) 306 << &II << DC << SS->getRange(); 307 else if (isDependentScopeSpecifier(*SS)) { 308 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 309 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 310 << SourceRange(SS->getRange().getBegin(), IILoc) 311 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 312 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 313 } else { 314 assert(SS && SS->isInvalid() && 315 "Invalid scope specifier has already been diagnosed"); 316 } 317 318 return true; 319} 320 321// Determines the context to return to after temporarily entering a 322// context. This depends in an unnecessarily complicated way on the 323// exact ordering of callbacks from the parser. 324DeclContext *Sema::getContainingDC(DeclContext *DC) { 325 326 // Functions defined inline within classes aren't parsed until we've 327 // finished parsing the top-level class, so the top-level class is 328 // the context we'll need to return to. 329 if (isa<FunctionDecl>(DC)) { 330 DC = DC->getLexicalParent(); 331 332 // A function not defined within a class will always return to its 333 // lexical context. 334 if (!isa<CXXRecordDecl>(DC)) 335 return DC; 336 337 // A C++ inline method/friend is parsed *after* the topmost class 338 // it was declared in is fully parsed ("complete"); the topmost 339 // class is the context we need to return to. 340 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 341 DC = RD; 342 343 // Return the declaration context of the topmost class the inline method is 344 // declared in. 345 return DC; 346 } 347 348 if (isa<ObjCMethodDecl>(DC)) 349 return Context.getTranslationUnitDecl(); 350 351 return DC->getLexicalParent(); 352} 353 354void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 355 assert(getContainingDC(DC) == CurContext && 356 "The next DeclContext should be lexically contained in the current one."); 357 CurContext = DC; 358 S->setEntity(DC); 359} 360 361void Sema::PopDeclContext() { 362 assert(CurContext && "DeclContext imbalance!"); 363 364 CurContext = getContainingDC(CurContext); 365} 366 367/// EnterDeclaratorContext - Used when we must lookup names in the context 368/// of a declarator's nested name specifier. 369/// 370void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 371 // C++0x [basic.lookup.unqual]p13: 372 // A name used in the definition of a static data member of class 373 // X (after the qualified-id of the static member) is looked up as 374 // if the name was used in a member function of X. 375 // C++0x [basic.lookup.unqual]p14: 376 // If a variable member of a namespace is defined outside of the 377 // scope of its namespace then any name used in the definition of 378 // the variable member (after the declarator-id) is looked up as 379 // if the definition of the variable member occurred in its 380 // namespace. 381 // Both of these imply that we should push a scope whose context 382 // is the semantic context of the declaration. We can't use 383 // PushDeclContext here because that context is not necessarily 384 // lexically contained in the current context. Fortunately, 385 // the containing scope should have the appropriate information. 386 387 assert(!S->getEntity() && "scope already has entity"); 388 389#ifndef NDEBUG 390 Scope *Ancestor = S->getParent(); 391 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 392 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 393#endif 394 395 CurContext = DC; 396 S->setEntity(DC); 397} 398 399void Sema::ExitDeclaratorContext(Scope *S) { 400 assert(S->getEntity() == CurContext && "Context imbalance!"); 401 402 // Switch back to the lexical context. The safety of this is 403 // enforced by an assert in EnterDeclaratorContext. 404 Scope *Ancestor = S->getParent(); 405 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 406 CurContext = (DeclContext*) Ancestor->getEntity(); 407 408 // We don't need to do anything with the scope, which is going to 409 // disappear. 410} 411 412/// \brief Determine whether we allow overloading of the function 413/// PrevDecl with another declaration. 414/// 415/// This routine determines whether overloading is possible, not 416/// whether some new function is actually an overload. It will return 417/// true in C++ (where we can always provide overloads) or, as an 418/// extension, in C when the previous function is already an 419/// overloaded function declaration or has the "overloadable" 420/// attribute. 421static bool AllowOverloadingOfFunction(LookupResult &Previous, 422 ASTContext &Context) { 423 if (Context.getLangOptions().CPlusPlus) 424 return true; 425 426 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 427 return true; 428 429 return (Previous.getResultKind() == LookupResult::Found 430 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 431} 432 433/// Add this decl to the scope shadowed decl chains. 434void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 435 // Move up the scope chain until we find the nearest enclosing 436 // non-transparent context. The declaration will be introduced into this 437 // scope. 438 while (S->getEntity() && 439 ((DeclContext *)S->getEntity())->isTransparentContext()) 440 S = S->getParent(); 441 442 // Add scoped declarations into their context, so that they can be 443 // found later. Declarations without a context won't be inserted 444 // into any context. 445 if (AddToContext) 446 CurContext->addDecl(D); 447 448 // Out-of-line definitions shouldn't be pushed into scope in C++. 449 // Out-of-line variable and function definitions shouldn't even in C. 450 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 451 D->isOutOfLine()) 452 return; 453 454 // Template instantiations should also not be pushed into scope. 455 if (isa<FunctionDecl>(D) && 456 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 457 return; 458 459 // If this replaces anything in the current scope, 460 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 461 IEnd = IdResolver.end(); 462 for (; I != IEnd; ++I) { 463 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 464 S->RemoveDecl(DeclPtrTy::make(*I)); 465 IdResolver.RemoveDecl(*I); 466 467 // Should only need to replace one decl. 468 break; 469 } 470 } 471 472 S->AddDecl(DeclPtrTy::make(D)); 473 IdResolver.AddDecl(D); 474} 475 476bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 477 return IdResolver.isDeclInScope(D, Ctx, Context, S); 478} 479 480static bool isOutOfScopePreviousDeclaration(NamedDecl *, 481 DeclContext*, 482 ASTContext&); 483 484/// Filters out lookup results that don't fall within the given scope 485/// as determined by isDeclInScope. 486static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 487 DeclContext *Ctx, Scope *S, 488 bool ConsiderLinkage) { 489 LookupResult::Filter F = R.makeFilter(); 490 while (F.hasNext()) { 491 NamedDecl *D = F.next(); 492 493 if (SemaRef.isDeclInScope(D, Ctx, S)) 494 continue; 495 496 if (ConsiderLinkage && 497 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 498 continue; 499 500 F.erase(); 501 } 502 503 F.done(); 504} 505 506static bool isUsingDecl(NamedDecl *D) { 507 return isa<UsingShadowDecl>(D) || 508 isa<UnresolvedUsingTypenameDecl>(D) || 509 isa<UnresolvedUsingValueDecl>(D); 510} 511 512/// Removes using shadow declarations from the lookup results. 513static void RemoveUsingDecls(LookupResult &R) { 514 LookupResult::Filter F = R.makeFilter(); 515 while (F.hasNext()) 516 if (isUsingDecl(F.next())) 517 F.erase(); 518 519 F.done(); 520} 521 522static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 523 if (D->isInvalidDecl()) 524 return false; 525 526 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 527 return false; 528 529 // White-list anything that isn't a local variable. 530 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 531 !D->getDeclContext()->isFunctionOrMethod()) 532 return false; 533 534 // Types of valid local variables should be complete, so this should succeed. 535 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 536 537 // White-list anything with an __attribute__((unused)) type. 538 QualType Ty = VD->getType(); 539 540 // Only look at the outermost level of typedef. 541 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 542 if (TT->getDecl()->hasAttr<UnusedAttr>()) 543 return false; 544 } 545 546 // If we failed to complete the type for some reason, don't 547 // diagnose the variable. 548 if (Ty->isIncompleteType()) 549 return false; 550 551 if (const TagType *TT = Ty->getAs<TagType>()) { 552 const TagDecl *Tag = TT->getDecl(); 553 if (Tag->hasAttr<UnusedAttr>()) 554 return false; 555 556 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 557 if (!RD->hasTrivialConstructor()) 558 return false; 559 if (!RD->hasTrivialDestructor()) 560 return false; 561 } 562 } 563 564 // TODO: __attribute__((unused)) templates? 565 } 566 567 return true; 568} 569 570void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 571 if (S->decl_empty()) return; 572 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 573 "Scope shouldn't contain decls!"); 574 575 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 576 I != E; ++I) { 577 Decl *TmpD = (*I).getAs<Decl>(); 578 assert(TmpD && "This decl didn't get pushed??"); 579 580 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 581 NamedDecl *D = cast<NamedDecl>(TmpD); 582 583 if (!D->getDeclName()) continue; 584 585 // Diagnose unused variables in this scope. 586 if (ShouldDiagnoseUnusedDecl(D) && 587 S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 588 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 589 590 // Remove this name from our lexical scope. 591 IdResolver.RemoveDecl(D); 592 } 593} 594 595/// \brief Look for an Objective-C class in the translation unit. 596/// 597/// \param Id The name of the Objective-C class we're looking for. If 598/// typo-correction fixes this name, the Id will be updated 599/// to the fixed name. 600/// 601/// \param IdLoc The location of the name in the translation unit. 602/// 603/// \param TypoCorrection If true, this routine will attempt typo correction 604/// if there is no class with the given name. 605/// 606/// \returns The declaration of the named Objective-C class, or NULL if the 607/// class could not be found. 608ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 609 SourceLocation IdLoc, 610 bool TypoCorrection) { 611 // The third "scope" argument is 0 since we aren't enabling lazy built-in 612 // creation from this context. 613 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 614 615 if (!IDecl && TypoCorrection) { 616 // Perform typo correction at the given location, but only if we 617 // find an Objective-C class name. 618 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 619 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 620 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 621 Diag(IdLoc, diag::err_undef_interface_suggest) 622 << Id << IDecl->getDeclName() 623 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 624 Diag(IDecl->getLocation(), diag::note_previous_decl) 625 << IDecl->getDeclName(); 626 627 Id = IDecl->getIdentifier(); 628 } 629 } 630 631 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 632} 633 634/// getNonFieldDeclScope - Retrieves the innermost scope, starting 635/// from S, where a non-field would be declared. This routine copes 636/// with the difference between C and C++ scoping rules in structs and 637/// unions. For example, the following code is well-formed in C but 638/// ill-formed in C++: 639/// @code 640/// struct S6 { 641/// enum { BAR } e; 642/// }; 643/// 644/// void test_S6() { 645/// struct S6 a; 646/// a.e = BAR; 647/// } 648/// @endcode 649/// For the declaration of BAR, this routine will return a different 650/// scope. The scope S will be the scope of the unnamed enumeration 651/// within S6. In C++, this routine will return the scope associated 652/// with S6, because the enumeration's scope is a transparent 653/// context but structures can contain non-field names. In C, this 654/// routine will return the translation unit scope, since the 655/// enumeration's scope is a transparent context and structures cannot 656/// contain non-field names. 657Scope *Sema::getNonFieldDeclScope(Scope *S) { 658 while (((S->getFlags() & Scope::DeclScope) == 0) || 659 (S->getEntity() && 660 ((DeclContext *)S->getEntity())->isTransparentContext()) || 661 (S->isClassScope() && !getLangOptions().CPlusPlus)) 662 S = S->getParent(); 663 return S; 664} 665 666void Sema::InitBuiltinVaListType() { 667 if (!Context.getBuiltinVaListType().isNull()) 668 return; 669 670 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 671 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 672 LookupOrdinaryName, ForRedeclaration); 673 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 674 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 675} 676 677/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 678/// file scope. lazily create a decl for it. ForRedeclaration is true 679/// if we're creating this built-in in anticipation of redeclaring the 680/// built-in. 681NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 682 Scope *S, bool ForRedeclaration, 683 SourceLocation Loc) { 684 Builtin::ID BID = (Builtin::ID)bid; 685 686 if (Context.BuiltinInfo.hasVAListUse(BID)) 687 InitBuiltinVaListType(); 688 689 ASTContext::GetBuiltinTypeError Error; 690 QualType R = Context.GetBuiltinType(BID, Error); 691 switch (Error) { 692 case ASTContext::GE_None: 693 // Okay 694 break; 695 696 case ASTContext::GE_Missing_stdio: 697 if (ForRedeclaration) 698 Diag(Loc, diag::err_implicit_decl_requires_stdio) 699 << Context.BuiltinInfo.GetName(BID); 700 return 0; 701 702 case ASTContext::GE_Missing_setjmp: 703 if (ForRedeclaration) 704 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 705 << Context.BuiltinInfo.GetName(BID); 706 return 0; 707 } 708 709 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 710 Diag(Loc, diag::ext_implicit_lib_function_decl) 711 << Context.BuiltinInfo.GetName(BID) 712 << R; 713 if (Context.BuiltinInfo.getHeaderName(BID) && 714 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 715 != Diagnostic::Ignored) 716 Diag(Loc, diag::note_please_include_header) 717 << Context.BuiltinInfo.getHeaderName(BID) 718 << Context.BuiltinInfo.GetName(BID); 719 } 720 721 FunctionDecl *New = FunctionDecl::Create(Context, 722 Context.getTranslationUnitDecl(), 723 Loc, II, R, /*TInfo=*/0, 724 FunctionDecl::Extern, 725 FunctionDecl::None, false, 726 /*hasPrototype=*/true); 727 New->setImplicit(); 728 729 // Create Decl objects for each parameter, adding them to the 730 // FunctionDecl. 731 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 732 llvm::SmallVector<ParmVarDecl*, 16> Params; 733 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 734 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 735 FT->getArgType(i), /*TInfo=*/0, 736 VarDecl::None, VarDecl::None, 0)); 737 New->setParams(Params.data(), Params.size()); 738 } 739 740 AddKnownFunctionAttributes(New); 741 742 // TUScope is the translation-unit scope to insert this function into. 743 // FIXME: This is hideous. We need to teach PushOnScopeChains to 744 // relate Scopes to DeclContexts, and probably eliminate CurContext 745 // entirely, but we're not there yet. 746 DeclContext *SavedContext = CurContext; 747 CurContext = Context.getTranslationUnitDecl(); 748 PushOnScopeChains(New, TUScope); 749 CurContext = SavedContext; 750 return New; 751} 752 753/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 754/// same name and scope as a previous declaration 'Old'. Figure out 755/// how to resolve this situation, merging decls or emitting 756/// diagnostics as appropriate. If there was an error, set New to be invalid. 757/// 758void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 759 // If the new decl is known invalid already, don't bother doing any 760 // merging checks. 761 if (New->isInvalidDecl()) return; 762 763 // Allow multiple definitions for ObjC built-in typedefs. 764 // FIXME: Verify the underlying types are equivalent! 765 if (getLangOptions().ObjC1) { 766 const IdentifierInfo *TypeID = New->getIdentifier(); 767 switch (TypeID->getLength()) { 768 default: break; 769 case 2: 770 if (!TypeID->isStr("id")) 771 break; 772 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 773 // Install the built-in type for 'id', ignoring the current definition. 774 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 775 return; 776 case 5: 777 if (!TypeID->isStr("Class")) 778 break; 779 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 780 // Install the built-in type for 'Class', ignoring the current definition. 781 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 782 return; 783 case 3: 784 if (!TypeID->isStr("SEL")) 785 break; 786 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 787 // Install the built-in type for 'SEL', ignoring the current definition. 788 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 789 return; 790 case 8: 791 if (!TypeID->isStr("Protocol")) 792 break; 793 Context.setObjCProtoType(New->getUnderlyingType()); 794 return; 795 } 796 // Fall through - the typedef name was not a builtin type. 797 } 798 799 // Verify the old decl was also a type. 800 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 801 if (!Old) { 802 Diag(New->getLocation(), diag::err_redefinition_different_kind) 803 << New->getDeclName(); 804 805 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 806 if (OldD->getLocation().isValid()) 807 Diag(OldD->getLocation(), diag::note_previous_definition); 808 809 return New->setInvalidDecl(); 810 } 811 812 // If the old declaration is invalid, just give up here. 813 if (Old->isInvalidDecl()) 814 return New->setInvalidDecl(); 815 816 // Determine the "old" type we'll use for checking and diagnostics. 817 QualType OldType; 818 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 819 OldType = OldTypedef->getUnderlyingType(); 820 else 821 OldType = Context.getTypeDeclType(Old); 822 823 // If the typedef types are not identical, reject them in all languages and 824 // with any extensions enabled. 825 826 if (OldType != New->getUnderlyingType() && 827 Context.getCanonicalType(OldType) != 828 Context.getCanonicalType(New->getUnderlyingType())) { 829 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 830 << New->getUnderlyingType() << OldType; 831 if (Old->getLocation().isValid()) 832 Diag(Old->getLocation(), diag::note_previous_definition); 833 return New->setInvalidDecl(); 834 } 835 836 // The types match. Link up the redeclaration chain if the old 837 // declaration was a typedef. 838 // FIXME: this is a potential source of wierdness if the type 839 // spellings don't match exactly. 840 if (isa<TypedefDecl>(Old)) 841 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 842 843 if (getLangOptions().Microsoft) 844 return; 845 846 if (getLangOptions().CPlusPlus) { 847 // C++ [dcl.typedef]p2: 848 // In a given non-class scope, a typedef specifier can be used to 849 // redefine the name of any type declared in that scope to refer 850 // to the type to which it already refers. 851 if (!isa<CXXRecordDecl>(CurContext)) 852 return; 853 854 // C++0x [dcl.typedef]p4: 855 // In a given class scope, a typedef specifier can be used to redefine 856 // any class-name declared in that scope that is not also a typedef-name 857 // to refer to the type to which it already refers. 858 // 859 // This wording came in via DR424, which was a correction to the 860 // wording in DR56, which accidentally banned code like: 861 // 862 // struct S { 863 // typedef struct A { } A; 864 // }; 865 // 866 // in the C++03 standard. We implement the C++0x semantics, which 867 // allow the above but disallow 868 // 869 // struct S { 870 // typedef int I; 871 // typedef int I; 872 // }; 873 // 874 // since that was the intent of DR56. 875 if (!isa<TypedefDecl >(Old)) 876 return; 877 878 Diag(New->getLocation(), diag::err_redefinition) 879 << New->getDeclName(); 880 Diag(Old->getLocation(), diag::note_previous_definition); 881 return New->setInvalidDecl(); 882 } 883 884 // If we have a redefinition of a typedef in C, emit a warning. This warning 885 // is normally mapped to an error, but can be controlled with 886 // -Wtypedef-redefinition. If either the original or the redefinition is 887 // in a system header, don't emit this for compatibility with GCC. 888 if (getDiagnostics().getSuppressSystemWarnings() && 889 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 890 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 891 return; 892 893 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 894 << New->getDeclName(); 895 Diag(Old->getLocation(), diag::note_previous_definition); 896 return; 897} 898 899/// DeclhasAttr - returns true if decl Declaration already has the target 900/// attribute. 901static bool 902DeclHasAttr(const Decl *decl, const Attr *target) { 903 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 904 if (attr->getKind() == target->getKind()) 905 return true; 906 907 return false; 908} 909 910/// MergeAttributes - append attributes from the Old decl to the New one. 911static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 912 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 913 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 914 Attr *NewAttr = attr->clone(C); 915 NewAttr->setInherited(true); 916 New->addAttr(NewAttr); 917 } 918 } 919} 920 921/// Used in MergeFunctionDecl to keep track of function parameters in 922/// C. 923struct GNUCompatibleParamWarning { 924 ParmVarDecl *OldParm; 925 ParmVarDecl *NewParm; 926 QualType PromotedType; 927}; 928 929 930/// getSpecialMember - get the special member enum for a method. 931Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 932 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 933 if (Ctor->isCopyConstructor()) 934 return Sema::CXXCopyConstructor; 935 936 return Sema::CXXConstructor; 937 } 938 939 if (isa<CXXDestructorDecl>(MD)) 940 return Sema::CXXDestructor; 941 942 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 943 return Sema::CXXCopyAssignment; 944} 945 946/// canREdefineFunction - checks if a function can be redefined. Currently, 947/// only extern inline functions can be redefined, and even then only in 948/// GNU89 mode. 949static bool canRedefineFunction(const FunctionDecl *FD, 950 const LangOptions& LangOpts) { 951 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 952 FD->isInlineSpecified() && 953 FD->getStorageClass() == FunctionDecl::Extern); 954} 955 956/// MergeFunctionDecl - We just parsed a function 'New' from 957/// declarator D which has the same name and scope as a previous 958/// declaration 'Old'. Figure out how to resolve this situation, 959/// merging decls or emitting diagnostics as appropriate. 960/// 961/// In C++, New and Old must be declarations that are not 962/// overloaded. Use IsOverload to determine whether New and Old are 963/// overloaded, and to select the Old declaration that New should be 964/// merged with. 965/// 966/// Returns true if there was an error, false otherwise. 967bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 968 // Verify the old decl was also a function. 969 FunctionDecl *Old = 0; 970 if (FunctionTemplateDecl *OldFunctionTemplate 971 = dyn_cast<FunctionTemplateDecl>(OldD)) 972 Old = OldFunctionTemplate->getTemplatedDecl(); 973 else 974 Old = dyn_cast<FunctionDecl>(OldD); 975 if (!Old) { 976 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 977 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 978 Diag(Shadow->getTargetDecl()->getLocation(), 979 diag::note_using_decl_target); 980 Diag(Shadow->getUsingDecl()->getLocation(), 981 diag::note_using_decl) << 0; 982 return true; 983 } 984 985 Diag(New->getLocation(), diag::err_redefinition_different_kind) 986 << New->getDeclName(); 987 Diag(OldD->getLocation(), diag::note_previous_definition); 988 return true; 989 } 990 991 // Determine whether the previous declaration was a definition, 992 // implicit declaration, or a declaration. 993 diag::kind PrevDiag; 994 if (Old->isThisDeclarationADefinition()) 995 PrevDiag = diag::note_previous_definition; 996 else if (Old->isImplicit()) 997 PrevDiag = diag::note_previous_implicit_declaration; 998 else 999 PrevDiag = diag::note_previous_declaration; 1000 1001 QualType OldQType = Context.getCanonicalType(Old->getType()); 1002 QualType NewQType = Context.getCanonicalType(New->getType()); 1003 1004 // Don't complain about this if we're in GNU89 mode and the old function 1005 // is an extern inline function. 1006 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1007 New->getStorageClass() == FunctionDecl::Static && 1008 Old->getStorageClass() != FunctionDecl::Static && 1009 !canRedefineFunction(Old, getLangOptions())) { 1010 Diag(New->getLocation(), diag::err_static_non_static) 1011 << New; 1012 Diag(Old->getLocation(), PrevDiag); 1013 return true; 1014 } 1015 1016 // If a function is first declared with a calling convention, but is 1017 // later declared or defined without one, the second decl assumes the 1018 // calling convention of the first. 1019 // 1020 // For the new decl, we have to look at the NON-canonical type to tell the 1021 // difference between a function that really doesn't have a calling 1022 // convention and one that is declared cdecl. That's because in 1023 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1024 // because it is the default calling convention. 1025 // 1026 // Note also that we DO NOT return at this point, because we still have 1027 // other tests to run. 1028 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1029 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1030 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1031 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1032 if (OldTypeInfo.getCC() != CC_Default && 1033 NewTypeInfo.getCC() == CC_Default) { 1034 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1035 New->setType(NewQType); 1036 NewQType = Context.getCanonicalType(NewQType); 1037 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1038 NewTypeInfo.getCC())) { 1039 // Calling conventions really aren't compatible, so complain. 1040 Diag(New->getLocation(), diag::err_cconv_change) 1041 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1042 << (OldTypeInfo.getCC() == CC_Default) 1043 << (OldTypeInfo.getCC() == CC_Default ? "" : 1044 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1045 Diag(Old->getLocation(), diag::note_previous_declaration); 1046 return true; 1047 } 1048 1049 // FIXME: diagnose the other way around? 1050 if (OldType->getNoReturnAttr() && 1051 !NewType->getNoReturnAttr()) { 1052 NewQType = Context.getNoReturnType(NewQType); 1053 New->setType(NewQType); 1054 assert(NewQType.isCanonical()); 1055 } 1056 1057 if (getLangOptions().CPlusPlus) { 1058 // (C++98 13.1p2): 1059 // Certain function declarations cannot be overloaded: 1060 // -- Function declarations that differ only in the return type 1061 // cannot be overloaded. 1062 QualType OldReturnType 1063 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1064 QualType NewReturnType 1065 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1066 if (OldReturnType != NewReturnType) { 1067 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1068 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1069 return true; 1070 } 1071 1072 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1073 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1074 if (OldMethod && NewMethod) { 1075 // Preserve triviality. 1076 NewMethod->setTrivial(OldMethod->isTrivial()); 1077 1078 bool isFriend = NewMethod->getFriendObjectKind(); 1079 1080 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1081 // -- Member function declarations with the same name and the 1082 // same parameter types cannot be overloaded if any of them 1083 // is a static member function declaration. 1084 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1085 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1086 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1087 return true; 1088 } 1089 1090 // C++ [class.mem]p1: 1091 // [...] A member shall not be declared twice in the 1092 // member-specification, except that a nested class or member 1093 // class template can be declared and then later defined. 1094 unsigned NewDiag; 1095 if (isa<CXXConstructorDecl>(OldMethod)) 1096 NewDiag = diag::err_constructor_redeclared; 1097 else if (isa<CXXDestructorDecl>(NewMethod)) 1098 NewDiag = diag::err_destructor_redeclared; 1099 else if (isa<CXXConversionDecl>(NewMethod)) 1100 NewDiag = diag::err_conv_function_redeclared; 1101 else 1102 NewDiag = diag::err_member_redeclared; 1103 1104 Diag(New->getLocation(), NewDiag); 1105 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1106 1107 // Complain if this is an explicit declaration of a special 1108 // member that was initially declared implicitly. 1109 // 1110 // As an exception, it's okay to befriend such methods in order 1111 // to permit the implicit constructor/destructor/operator calls. 1112 } else if (OldMethod->isImplicit()) { 1113 if (isFriend) { 1114 NewMethod->setImplicit(); 1115 } else { 1116 Diag(NewMethod->getLocation(), 1117 diag::err_definition_of_implicitly_declared_member) 1118 << New << getSpecialMember(OldMethod); 1119 return true; 1120 } 1121 } 1122 } 1123 1124 // (C++98 8.3.5p3): 1125 // All declarations for a function shall agree exactly in both the 1126 // return type and the parameter-type-list. 1127 // attributes should be ignored when comparing. 1128 if (Context.getNoReturnType(OldQType, false) == 1129 Context.getNoReturnType(NewQType, false)) 1130 return MergeCompatibleFunctionDecls(New, Old); 1131 1132 // Fall through for conflicting redeclarations and redefinitions. 1133 } 1134 1135 // C: Function types need to be compatible, not identical. This handles 1136 // duplicate function decls like "void f(int); void f(enum X);" properly. 1137 if (!getLangOptions().CPlusPlus && 1138 Context.typesAreCompatible(OldQType, NewQType)) { 1139 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1140 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1141 const FunctionProtoType *OldProto = 0; 1142 if (isa<FunctionNoProtoType>(NewFuncType) && 1143 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1144 // The old declaration provided a function prototype, but the 1145 // new declaration does not. Merge in the prototype. 1146 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1147 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1148 OldProto->arg_type_end()); 1149 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1150 ParamTypes.data(), ParamTypes.size(), 1151 OldProto->isVariadic(), 1152 OldProto->getTypeQuals(), 1153 false, false, 0, 0, 1154 OldProto->getExtInfo()); 1155 New->setType(NewQType); 1156 New->setHasInheritedPrototype(); 1157 1158 // Synthesize a parameter for each argument type. 1159 llvm::SmallVector<ParmVarDecl*, 16> Params; 1160 for (FunctionProtoType::arg_type_iterator 1161 ParamType = OldProto->arg_type_begin(), 1162 ParamEnd = OldProto->arg_type_end(); 1163 ParamType != ParamEnd; ++ParamType) { 1164 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1165 SourceLocation(), 0, 1166 *ParamType, /*TInfo=*/0, 1167 VarDecl::None, VarDecl::None, 1168 0); 1169 Param->setImplicit(); 1170 Params.push_back(Param); 1171 } 1172 1173 New->setParams(Params.data(), Params.size()); 1174 } 1175 1176 return MergeCompatibleFunctionDecls(New, Old); 1177 } 1178 1179 // GNU C permits a K&R definition to follow a prototype declaration 1180 // if the declared types of the parameters in the K&R definition 1181 // match the types in the prototype declaration, even when the 1182 // promoted types of the parameters from the K&R definition differ 1183 // from the types in the prototype. GCC then keeps the types from 1184 // the prototype. 1185 // 1186 // If a variadic prototype is followed by a non-variadic K&R definition, 1187 // the K&R definition becomes variadic. This is sort of an edge case, but 1188 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1189 // C99 6.9.1p8. 1190 if (!getLangOptions().CPlusPlus && 1191 Old->hasPrototype() && !New->hasPrototype() && 1192 New->getType()->getAs<FunctionProtoType>() && 1193 Old->getNumParams() == New->getNumParams()) { 1194 llvm::SmallVector<QualType, 16> ArgTypes; 1195 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1196 const FunctionProtoType *OldProto 1197 = Old->getType()->getAs<FunctionProtoType>(); 1198 const FunctionProtoType *NewProto 1199 = New->getType()->getAs<FunctionProtoType>(); 1200 1201 // Determine whether this is the GNU C extension. 1202 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1203 NewProto->getResultType()); 1204 bool LooseCompatible = !MergedReturn.isNull(); 1205 for (unsigned Idx = 0, End = Old->getNumParams(); 1206 LooseCompatible && Idx != End; ++Idx) { 1207 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1208 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1209 if (Context.typesAreCompatible(OldParm->getType(), 1210 NewProto->getArgType(Idx))) { 1211 ArgTypes.push_back(NewParm->getType()); 1212 } else if (Context.typesAreCompatible(OldParm->getType(), 1213 NewParm->getType())) { 1214 GNUCompatibleParamWarning Warn 1215 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1216 Warnings.push_back(Warn); 1217 ArgTypes.push_back(NewParm->getType()); 1218 } else 1219 LooseCompatible = false; 1220 } 1221 1222 if (LooseCompatible) { 1223 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1224 Diag(Warnings[Warn].NewParm->getLocation(), 1225 diag::ext_param_promoted_not_compatible_with_prototype) 1226 << Warnings[Warn].PromotedType 1227 << Warnings[Warn].OldParm->getType(); 1228 Diag(Warnings[Warn].OldParm->getLocation(), 1229 diag::note_previous_declaration); 1230 } 1231 1232 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1233 ArgTypes.size(), 1234 OldProto->isVariadic(), 0, 1235 false, false, 0, 0, 1236 OldProto->getExtInfo())); 1237 return MergeCompatibleFunctionDecls(New, Old); 1238 } 1239 1240 // Fall through to diagnose conflicting types. 1241 } 1242 1243 // A function that has already been declared has been redeclared or defined 1244 // with a different type- show appropriate diagnostic 1245 if (unsigned BuiltinID = Old->getBuiltinID()) { 1246 // The user has declared a builtin function with an incompatible 1247 // signature. 1248 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1249 // The function the user is redeclaring is a library-defined 1250 // function like 'malloc' or 'printf'. Warn about the 1251 // redeclaration, then pretend that we don't know about this 1252 // library built-in. 1253 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1254 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1255 << Old << Old->getType(); 1256 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1257 Old->setInvalidDecl(); 1258 return false; 1259 } 1260 1261 PrevDiag = diag::note_previous_builtin_declaration; 1262 } 1263 1264 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1265 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1266 return true; 1267} 1268 1269/// \brief Completes the merge of two function declarations that are 1270/// known to be compatible. 1271/// 1272/// This routine handles the merging of attributes and other 1273/// properties of function declarations form the old declaration to 1274/// the new declaration, once we know that New is in fact a 1275/// redeclaration of Old. 1276/// 1277/// \returns false 1278bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1279 // Merge the attributes 1280 MergeAttributes(New, Old, Context); 1281 1282 // Merge the storage class. 1283 if (Old->getStorageClass() != FunctionDecl::Extern && 1284 Old->getStorageClass() != FunctionDecl::None) 1285 New->setStorageClass(Old->getStorageClass()); 1286 1287 // Merge "pure" flag. 1288 if (Old->isPure()) 1289 New->setPure(); 1290 1291 // Merge the "deleted" flag. 1292 if (Old->isDeleted()) 1293 New->setDeleted(); 1294 1295 if (getLangOptions().CPlusPlus) 1296 return MergeCXXFunctionDecl(New, Old); 1297 1298 return false; 1299} 1300 1301/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1302/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1303/// situation, merging decls or emitting diagnostics as appropriate. 1304/// 1305/// Tentative definition rules (C99 6.9.2p2) are checked by 1306/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1307/// definitions here, since the initializer hasn't been attached. 1308/// 1309void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1310 // If the new decl is already invalid, don't do any other checking. 1311 if (New->isInvalidDecl()) 1312 return; 1313 1314 // Verify the old decl was also a variable. 1315 VarDecl *Old = 0; 1316 if (!Previous.isSingleResult() || 1317 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1318 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1319 << New->getDeclName(); 1320 Diag(Previous.getRepresentativeDecl()->getLocation(), 1321 diag::note_previous_definition); 1322 return New->setInvalidDecl(); 1323 } 1324 1325 MergeAttributes(New, Old, Context); 1326 1327 // Merge the types 1328 QualType MergedT; 1329 if (getLangOptions().CPlusPlus) { 1330 if (Context.hasSameType(New->getType(), Old->getType())) 1331 MergedT = New->getType(); 1332 // C++ [basic.link]p10: 1333 // [...] the types specified by all declarations referring to a given 1334 // object or function shall be identical, except that declarations for an 1335 // array object can specify array types that differ by the presence or 1336 // absence of a major array bound (8.3.4). 1337 else if (Old->getType()->isIncompleteArrayType() && 1338 New->getType()->isArrayType()) { 1339 CanQual<ArrayType> OldArray 1340 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1341 CanQual<ArrayType> NewArray 1342 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1343 if (OldArray->getElementType() == NewArray->getElementType()) 1344 MergedT = New->getType(); 1345 } else if (Old->getType()->isArrayType() && 1346 New->getType()->isIncompleteArrayType()) { 1347 CanQual<ArrayType> OldArray 1348 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1349 CanQual<ArrayType> NewArray 1350 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1351 if (OldArray->getElementType() == NewArray->getElementType()) 1352 MergedT = Old->getType(); 1353 } 1354 } else { 1355 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1356 } 1357 if (MergedT.isNull()) { 1358 Diag(New->getLocation(), diag::err_redefinition_different_type) 1359 << New->getDeclName(); 1360 Diag(Old->getLocation(), diag::note_previous_definition); 1361 return New->setInvalidDecl(); 1362 } 1363 New->setType(MergedT); 1364 1365 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1366 if (New->getStorageClass() == VarDecl::Static && 1367 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1368 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1369 Diag(Old->getLocation(), diag::note_previous_definition); 1370 return New->setInvalidDecl(); 1371 } 1372 // C99 6.2.2p4: 1373 // For an identifier declared with the storage-class specifier 1374 // extern in a scope in which a prior declaration of that 1375 // identifier is visible,23) if the prior declaration specifies 1376 // internal or external linkage, the linkage of the identifier at 1377 // the later declaration is the same as the linkage specified at 1378 // the prior declaration. If no prior declaration is visible, or 1379 // if the prior declaration specifies no linkage, then the 1380 // identifier has external linkage. 1381 if (New->hasExternalStorage() && Old->hasLinkage()) 1382 /* Okay */; 1383 else if (New->getStorageClass() != VarDecl::Static && 1384 Old->getStorageClass() == VarDecl::Static) { 1385 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1386 Diag(Old->getLocation(), diag::note_previous_definition); 1387 return New->setInvalidDecl(); 1388 } 1389 1390 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1391 1392 // FIXME: The test for external storage here seems wrong? We still 1393 // need to check for mismatches. 1394 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1395 // Don't complain about out-of-line definitions of static members. 1396 !(Old->getLexicalDeclContext()->isRecord() && 1397 !New->getLexicalDeclContext()->isRecord())) { 1398 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1399 Diag(Old->getLocation(), diag::note_previous_definition); 1400 return New->setInvalidDecl(); 1401 } 1402 1403 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1404 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1405 Diag(Old->getLocation(), diag::note_previous_definition); 1406 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1407 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1408 Diag(Old->getLocation(), diag::note_previous_definition); 1409 } 1410 1411 // C++ doesn't have tentative definitions, so go right ahead and check here. 1412 const VarDecl *Def; 1413 if (getLangOptions().CPlusPlus && 1414 New->isThisDeclarationADefinition() == VarDecl::Definition && 1415 (Def = Old->getDefinition())) { 1416 Diag(New->getLocation(), diag::err_redefinition) 1417 << New->getDeclName(); 1418 Diag(Def->getLocation(), diag::note_previous_definition); 1419 New->setInvalidDecl(); 1420 return; 1421 } 1422 1423 // Keep a chain of previous declarations. 1424 New->setPreviousDeclaration(Old); 1425 1426 // Inherit access appropriately. 1427 New->setAccess(Old->getAccess()); 1428} 1429 1430/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1431/// no declarator (e.g. "struct foo;") is parsed. 1432Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1433 // FIXME: Error on auto/register at file scope 1434 // FIXME: Error on inline/virtual/explicit 1435 // FIXME: Warn on useless __thread 1436 // FIXME: Warn on useless const/volatile 1437 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1438 // FIXME: Warn on useless attributes 1439 Decl *TagD = 0; 1440 TagDecl *Tag = 0; 1441 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1442 DS.getTypeSpecType() == DeclSpec::TST_struct || 1443 DS.getTypeSpecType() == DeclSpec::TST_union || 1444 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1445 TagD = static_cast<Decl *>(DS.getTypeRep()); 1446 1447 if (!TagD) // We probably had an error 1448 return DeclPtrTy(); 1449 1450 // Note that the above type specs guarantee that the 1451 // type rep is a Decl, whereas in many of the others 1452 // it's a Type. 1453 Tag = dyn_cast<TagDecl>(TagD); 1454 } 1455 1456 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1457 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1458 // or incomplete types shall not be restrict-qualified." 1459 if (TypeQuals & DeclSpec::TQ_restrict) 1460 Diag(DS.getRestrictSpecLoc(), 1461 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1462 << DS.getSourceRange(); 1463 } 1464 1465 if (DS.isFriendSpecified()) { 1466 // If we're dealing with a class template decl, assume that the 1467 // template routines are handling it. 1468 if (TagD && isa<ClassTemplateDecl>(TagD)) 1469 return DeclPtrTy(); 1470 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1471 } 1472 1473 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1474 // If there are attributes in the DeclSpec, apply them to the record. 1475 if (const AttributeList *AL = DS.getAttributes()) 1476 ProcessDeclAttributeList(S, Record, AL); 1477 1478 if (!Record->getDeclName() && Record->isDefinition() && 1479 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1480 if (getLangOptions().CPlusPlus || 1481 Record->getDeclContext()->isRecord()) 1482 return BuildAnonymousStructOrUnion(S, DS, Record); 1483 1484 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1485 << DS.getSourceRange(); 1486 } 1487 1488 // Microsoft allows unnamed struct/union fields. Don't complain 1489 // about them. 1490 // FIXME: Should we support Microsoft's extensions in this area? 1491 if (Record->getDeclName() && getLangOptions().Microsoft) 1492 return DeclPtrTy::make(Tag); 1493 } 1494 1495 if (!DS.isMissingDeclaratorOk() && 1496 DS.getTypeSpecType() != DeclSpec::TST_error) { 1497 // Warn about typedefs of enums without names, since this is an 1498 // extension in both Microsoft an GNU. 1499 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1500 Tag && isa<EnumDecl>(Tag)) { 1501 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1502 << DS.getSourceRange(); 1503 return DeclPtrTy::make(Tag); 1504 } 1505 1506 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1507 << DS.getSourceRange(); 1508 } 1509 1510 return DeclPtrTy::make(Tag); 1511} 1512 1513/// We are trying to inject an anonymous member into the given scope; 1514/// check if there's an existing declaration that can't be overloaded. 1515/// 1516/// \return true if this is a forbidden redeclaration 1517static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1518 Scope *S, 1519 DeclContext *Owner, 1520 DeclarationName Name, 1521 SourceLocation NameLoc, 1522 unsigned diagnostic) { 1523 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1524 Sema::ForRedeclaration); 1525 if (!SemaRef.LookupName(R, S)) return false; 1526 1527 if (R.getAsSingle<TagDecl>()) 1528 return false; 1529 1530 // Pick a representative declaration. 1531 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1532 if (PrevDecl && Owner->isRecord()) { 1533 RecordDecl *Record = cast<RecordDecl>(Owner); 1534 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1535 return false; 1536 } 1537 1538 SemaRef.Diag(NameLoc, diagnostic) << Name; 1539 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1540 1541 return true; 1542} 1543 1544/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1545/// anonymous struct or union AnonRecord into the owning context Owner 1546/// and scope S. This routine will be invoked just after we realize 1547/// that an unnamed union or struct is actually an anonymous union or 1548/// struct, e.g., 1549/// 1550/// @code 1551/// union { 1552/// int i; 1553/// float f; 1554/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1555/// // f into the surrounding scope.x 1556/// @endcode 1557/// 1558/// This routine is recursive, injecting the names of nested anonymous 1559/// structs/unions into the owning context and scope as well. 1560bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1561 RecordDecl *AnonRecord) { 1562 unsigned diagKind 1563 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1564 : diag::err_anonymous_struct_member_redecl; 1565 1566 bool Invalid = false; 1567 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1568 FEnd = AnonRecord->field_end(); 1569 F != FEnd; ++F) { 1570 if ((*F)->getDeclName()) { 1571 if (CheckAnonMemberRedeclaration(*this, S, Owner, (*F)->getDeclName(), 1572 (*F)->getLocation(), diagKind)) { 1573 // C++ [class.union]p2: 1574 // The names of the members of an anonymous union shall be 1575 // distinct from the names of any other entity in the 1576 // scope in which the anonymous union is declared. 1577 Invalid = true; 1578 } else { 1579 // C++ [class.union]p2: 1580 // For the purpose of name lookup, after the anonymous union 1581 // definition, the members of the anonymous union are 1582 // considered to have been defined in the scope in which the 1583 // anonymous union is declared. 1584 Owner->makeDeclVisibleInContext(*F); 1585 S->AddDecl(DeclPtrTy::make(*F)); 1586 IdResolver.AddDecl(*F); 1587 } 1588 } else if (const RecordType *InnerRecordType 1589 = (*F)->getType()->getAs<RecordType>()) { 1590 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1591 if (InnerRecord->isAnonymousStructOrUnion()) 1592 Invalid = Invalid || 1593 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1594 } 1595 } 1596 1597 return Invalid; 1598} 1599 1600/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1601/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1602/// illegal input values are mapped to VarDecl::None. 1603/// If the input declaration context is a linkage specification 1604/// with no braces, then Extern is mapped to None. 1605static VarDecl::StorageClass 1606StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1607 DeclContext *DC) { 1608 switch (StorageClassSpec) { 1609 case DeclSpec::SCS_unspecified: return VarDecl::None; 1610 case DeclSpec::SCS_extern: 1611 // If the current context is a C++ linkage specification 1612 // having no braces, then the keyword "extern" is properly part 1613 // of the linkage specification itself, rather than being 1614 // the written storage class specifier. 1615 return (DC && isa<LinkageSpecDecl>(DC) && 1616 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1617 ? VarDecl::None : VarDecl::Extern; 1618 case DeclSpec::SCS_static: return VarDecl::Static; 1619 case DeclSpec::SCS_auto: return VarDecl::Auto; 1620 case DeclSpec::SCS_register: return VarDecl::Register; 1621 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1622 // Illegal SCSs map to None: error reporting is up to the caller. 1623 case DeclSpec::SCS_mutable: // Fall through. 1624 case DeclSpec::SCS_typedef: return VarDecl::None; 1625 } 1626 llvm_unreachable("unknown storage class specifier"); 1627} 1628 1629/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1630/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1631/// illegal input values are mapped to FunctionDecl::None. 1632/// If the input declaration context is a linkage specification 1633/// with no braces, then Extern is mapped to None. 1634static FunctionDecl::StorageClass 1635StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1636 DeclContext *DC) { 1637 switch (StorageClassSpec) { 1638 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1639 case DeclSpec::SCS_extern: 1640 // If the current context is a C++ linkage specification 1641 // having no braces, then the keyword "extern" is properly part 1642 // of the linkage specification itself, rather than being 1643 // the written storage class specifier. 1644 return (DC && isa<LinkageSpecDecl>(DC) && 1645 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1646 ? FunctionDecl::None : FunctionDecl::Extern; 1647 case DeclSpec::SCS_static: return FunctionDecl::Static; 1648 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1649 // Illegal SCSs map to None: error reporting is up to the caller. 1650 case DeclSpec::SCS_auto: // Fall through. 1651 case DeclSpec::SCS_mutable: // Fall through. 1652 case DeclSpec::SCS_register: // Fall through. 1653 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1654 } 1655 llvm_unreachable("unknown storage class specifier"); 1656} 1657 1658/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1659/// anonymous structure or union. Anonymous unions are a C++ feature 1660/// (C++ [class.union]) and a GNU C extension; anonymous structures 1661/// are a GNU C and GNU C++ extension. 1662Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1663 RecordDecl *Record) { 1664 DeclContext *Owner = Record->getDeclContext(); 1665 1666 // Diagnose whether this anonymous struct/union is an extension. 1667 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1668 Diag(Record->getLocation(), diag::ext_anonymous_union); 1669 else if (!Record->isUnion()) 1670 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1671 1672 // C and C++ require different kinds of checks for anonymous 1673 // structs/unions. 1674 bool Invalid = false; 1675 if (getLangOptions().CPlusPlus) { 1676 const char* PrevSpec = 0; 1677 unsigned DiagID; 1678 // C++ [class.union]p3: 1679 // Anonymous unions declared in a named namespace or in the 1680 // global namespace shall be declared static. 1681 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1682 (isa<TranslationUnitDecl>(Owner) || 1683 (isa<NamespaceDecl>(Owner) && 1684 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1685 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1686 Invalid = true; 1687 1688 // Recover by adding 'static'. 1689 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1690 PrevSpec, DiagID); 1691 } 1692 // C++ [class.union]p3: 1693 // A storage class is not allowed in a declaration of an 1694 // anonymous union in a class scope. 1695 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1696 isa<RecordDecl>(Owner)) { 1697 Diag(DS.getStorageClassSpecLoc(), 1698 diag::err_anonymous_union_with_storage_spec); 1699 Invalid = true; 1700 1701 // Recover by removing the storage specifier. 1702 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1703 PrevSpec, DiagID); 1704 } 1705 1706 // C++ [class.union]p2: 1707 // The member-specification of an anonymous union shall only 1708 // define non-static data members. [Note: nested types and 1709 // functions cannot be declared within an anonymous union. ] 1710 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1711 MemEnd = Record->decls_end(); 1712 Mem != MemEnd; ++Mem) { 1713 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1714 // C++ [class.union]p3: 1715 // An anonymous union shall not have private or protected 1716 // members (clause 11). 1717 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1718 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1719 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1720 Invalid = true; 1721 } 1722 } else if ((*Mem)->isImplicit()) { 1723 // Any implicit members are fine. 1724 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1725 // This is a type that showed up in an 1726 // elaborated-type-specifier inside the anonymous struct or 1727 // union, but which actually declares a type outside of the 1728 // anonymous struct or union. It's okay. 1729 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1730 if (!MemRecord->isAnonymousStructOrUnion() && 1731 MemRecord->getDeclName()) { 1732 // This is a nested type declaration. 1733 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1734 << (int)Record->isUnion(); 1735 Invalid = true; 1736 } 1737 } else { 1738 // We have something that isn't a non-static data 1739 // member. Complain about it. 1740 unsigned DK = diag::err_anonymous_record_bad_member; 1741 if (isa<TypeDecl>(*Mem)) 1742 DK = diag::err_anonymous_record_with_type; 1743 else if (isa<FunctionDecl>(*Mem)) 1744 DK = diag::err_anonymous_record_with_function; 1745 else if (isa<VarDecl>(*Mem)) 1746 DK = diag::err_anonymous_record_with_static; 1747 Diag((*Mem)->getLocation(), DK) 1748 << (int)Record->isUnion(); 1749 Invalid = true; 1750 } 1751 } 1752 } 1753 1754 if (!Record->isUnion() && !Owner->isRecord()) { 1755 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1756 << (int)getLangOptions().CPlusPlus; 1757 Invalid = true; 1758 } 1759 1760 // Mock up a declarator. 1761 Declarator Dc(DS, Declarator::TypeNameContext); 1762 TypeSourceInfo *TInfo = 0; 1763 GetTypeForDeclarator(Dc, S, &TInfo); 1764 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1765 1766 // Create a declaration for this anonymous struct/union. 1767 NamedDecl *Anon = 0; 1768 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1769 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1770 /*IdentifierInfo=*/0, 1771 Context.getTypeDeclType(Record), 1772 TInfo, 1773 /*BitWidth=*/0, /*Mutable=*/false); 1774 Anon->setAccess(AS_public); 1775 if (getLangOptions().CPlusPlus) 1776 FieldCollector->Add(cast<FieldDecl>(Anon)); 1777 } else { 1778 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1779 assert(SCSpec != DeclSpec::SCS_typedef && 1780 "Parser allowed 'typedef' as storage class VarDecl."); 1781 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1782 if (SCSpec == DeclSpec::SCS_mutable) { 1783 // mutable can only appear on non-static class members, so it's always 1784 // an error here 1785 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1786 Invalid = true; 1787 SC = VarDecl::None; 1788 } 1789 SCSpec = DS.getStorageClassSpecAsWritten(); 1790 VarDecl::StorageClass SCAsWritten 1791 = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1792 1793 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1794 /*IdentifierInfo=*/0, 1795 Context.getTypeDeclType(Record), 1796 TInfo, SC, SCAsWritten); 1797 } 1798 Anon->setImplicit(); 1799 1800 // Add the anonymous struct/union object to the current 1801 // context. We'll be referencing this object when we refer to one of 1802 // its members. 1803 Owner->addDecl(Anon); 1804 1805 // Inject the members of the anonymous struct/union into the owning 1806 // context and into the identifier resolver chain for name lookup 1807 // purposes. 1808 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1809 Invalid = true; 1810 1811 // Mark this as an anonymous struct/union type. Note that we do not 1812 // do this until after we have already checked and injected the 1813 // members of this anonymous struct/union type, because otherwise 1814 // the members could be injected twice: once by DeclContext when it 1815 // builds its lookup table, and once by 1816 // InjectAnonymousStructOrUnionMembers. 1817 Record->setAnonymousStructOrUnion(true); 1818 1819 if (Invalid) 1820 Anon->setInvalidDecl(); 1821 1822 return DeclPtrTy::make(Anon); 1823} 1824 1825 1826/// GetNameForDeclarator - Determine the full declaration name for the 1827/// given Declarator. 1828DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1829 return GetNameFromUnqualifiedId(D.getName()); 1830} 1831 1832/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1833DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1834 switch (Name.getKind()) { 1835 case UnqualifiedId::IK_Identifier: 1836 return DeclarationName(Name.Identifier); 1837 1838 case UnqualifiedId::IK_OperatorFunctionId: 1839 return Context.DeclarationNames.getCXXOperatorName( 1840 Name.OperatorFunctionId.Operator); 1841 1842 case UnqualifiedId::IK_LiteralOperatorId: 1843 return Context.DeclarationNames.getCXXLiteralOperatorName( 1844 Name.Identifier); 1845 1846 case UnqualifiedId::IK_ConversionFunctionId: { 1847 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1848 if (Ty.isNull()) 1849 return DeclarationName(); 1850 1851 return Context.DeclarationNames.getCXXConversionFunctionName( 1852 Context.getCanonicalType(Ty)); 1853 } 1854 1855 case UnqualifiedId::IK_ConstructorName: { 1856 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1857 if (Ty.isNull()) 1858 return DeclarationName(); 1859 1860 return Context.DeclarationNames.getCXXConstructorName( 1861 Context.getCanonicalType(Ty)); 1862 } 1863 1864 case UnqualifiedId::IK_ConstructorTemplateId: { 1865 // In well-formed code, we can only have a constructor 1866 // template-id that refers to the current context, so go there 1867 // to find the actual type being constructed. 1868 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1869 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1870 return DeclarationName(); 1871 1872 // Determine the type of the class being constructed. 1873 QualType CurClassType = Context.getTypeDeclType(CurClass); 1874 1875 // FIXME: Check two things: that the template-id names the same type as 1876 // CurClassType, and that the template-id does not occur when the name 1877 // was qualified. 1878 1879 return Context.DeclarationNames.getCXXConstructorName( 1880 Context.getCanonicalType(CurClassType)); 1881 } 1882 1883 case UnqualifiedId::IK_DestructorName: { 1884 QualType Ty = GetTypeFromParser(Name.DestructorName); 1885 if (Ty.isNull()) 1886 return DeclarationName(); 1887 1888 return Context.DeclarationNames.getCXXDestructorName( 1889 Context.getCanonicalType(Ty)); 1890 } 1891 1892 case UnqualifiedId::IK_TemplateId: { 1893 TemplateName TName 1894 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1895 return Context.getNameForTemplate(TName); 1896 } 1897 } 1898 1899 assert(false && "Unknown name kind"); 1900 return DeclarationName(); 1901} 1902 1903/// isNearlyMatchingFunction - Determine whether the C++ functions 1904/// Declaration and Definition are "nearly" matching. This heuristic 1905/// is used to improve diagnostics in the case where an out-of-line 1906/// function definition doesn't match any declaration within 1907/// the class or namespace. 1908static bool isNearlyMatchingFunction(ASTContext &Context, 1909 FunctionDecl *Declaration, 1910 FunctionDecl *Definition) { 1911 if (Declaration->param_size() != Definition->param_size()) 1912 return false; 1913 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1914 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1915 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1916 1917 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1918 DefParamTy.getNonReferenceType())) 1919 return false; 1920 } 1921 1922 return true; 1923} 1924 1925Sema::DeclPtrTy 1926Sema::HandleDeclarator(Scope *S, Declarator &D, 1927 MultiTemplateParamsArg TemplateParamLists, 1928 bool IsFunctionDefinition) { 1929 DeclarationName Name = GetNameForDeclarator(D); 1930 1931 // All of these full declarators require an identifier. If it doesn't have 1932 // one, the ParsedFreeStandingDeclSpec action should be used. 1933 if (!Name) { 1934 if (!D.isInvalidType()) // Reject this if we think it is valid. 1935 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1936 diag::err_declarator_need_ident) 1937 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1938 return DeclPtrTy(); 1939 } 1940 1941 // The scope passed in may not be a decl scope. Zip up the scope tree until 1942 // we find one that is. 1943 while ((S->getFlags() & Scope::DeclScope) == 0 || 1944 (S->getFlags() & Scope::TemplateParamScope) != 0) 1945 S = S->getParent(); 1946 1947 // If this is an out-of-line definition of a member of a class template 1948 // or class template partial specialization, we may need to rebuild the 1949 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1950 // for more information. 1951 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1952 // handle expressions properly. 1953 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1954 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1955 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1956 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1957 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1958 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1959 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1960 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1961 // FIXME: Preserve type source info. 1962 QualType T = GetTypeFromParser(DS.getTypeRep()); 1963 1964 DeclContext *SavedContext = CurContext; 1965 CurContext = DC; 1966 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1967 CurContext = SavedContext; 1968 1969 if (T.isNull()) 1970 return DeclPtrTy(); 1971 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1972 } 1973 } 1974 1975 DeclContext *DC; 1976 NamedDecl *New; 1977 1978 TypeSourceInfo *TInfo = 0; 1979 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1980 1981 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1982 ForRedeclaration); 1983 1984 // See if this is a redefinition of a variable in the same scope. 1985 if (D.getCXXScopeSpec().isInvalid()) { 1986 DC = CurContext; 1987 D.setInvalidType(); 1988 } else if (!D.getCXXScopeSpec().isSet()) { 1989 bool IsLinkageLookup = false; 1990 1991 // If the declaration we're planning to build will be a function 1992 // or object with linkage, then look for another declaration with 1993 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1994 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1995 /* Do nothing*/; 1996 else if (R->isFunctionType()) { 1997 if (CurContext->isFunctionOrMethod() || 1998 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1999 IsLinkageLookup = true; 2000 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2001 IsLinkageLookup = true; 2002 else if (CurContext->getLookupContext()->isTranslationUnit() && 2003 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2004 IsLinkageLookup = true; 2005 2006 if (IsLinkageLookup) 2007 Previous.clear(LookupRedeclarationWithLinkage); 2008 2009 DC = CurContext; 2010 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2011 } else { // Something like "int foo::x;" 2012 DC = computeDeclContext(D.getCXXScopeSpec(), true); 2013 2014 if (!DC) { 2015 // If we could not compute the declaration context, it's because the 2016 // declaration context is dependent but does not refer to a class, 2017 // class template, or class template partial specialization. Complain 2018 // and return early, to avoid the coming semantic disaster. 2019 Diag(D.getIdentifierLoc(), 2020 diag::err_template_qualified_declarator_no_match) 2021 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2022 << D.getCXXScopeSpec().getRange(); 2023 return DeclPtrTy(); 2024 } 2025 2026 if (!DC->isDependentContext() && 2027 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2028 return DeclPtrTy(); 2029 2030 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2031 Diag(D.getIdentifierLoc(), 2032 diag::err_member_def_undefined_record) 2033 << Name << DC << D.getCXXScopeSpec().getRange(); 2034 D.setInvalidType(); 2035 } 2036 2037 LookupQualifiedName(Previous, DC); 2038 2039 // Don't consider using declarations as previous declarations for 2040 // out-of-line members. 2041 RemoveUsingDecls(Previous); 2042 2043 // C++ 7.3.1.2p2: 2044 // Members (including explicit specializations of templates) of a named 2045 // namespace can also be defined outside that namespace by explicit 2046 // qualification of the name being defined, provided that the entity being 2047 // defined was already declared in the namespace and the definition appears 2048 // after the point of declaration in a namespace that encloses the 2049 // declarations namespace. 2050 // 2051 // Note that we only check the context at this point. We don't yet 2052 // have enough information to make sure that PrevDecl is actually 2053 // the declaration we want to match. For example, given: 2054 // 2055 // class X { 2056 // void f(); 2057 // void f(float); 2058 // }; 2059 // 2060 // void X::f(int) { } // ill-formed 2061 // 2062 // In this case, PrevDecl will point to the overload set 2063 // containing the two f's declared in X, but neither of them 2064 // matches. 2065 2066 // First check whether we named the global scope. 2067 if (isa<TranslationUnitDecl>(DC)) { 2068 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2069 << Name << D.getCXXScopeSpec().getRange(); 2070 } else { 2071 DeclContext *Cur = CurContext; 2072 while (isa<LinkageSpecDecl>(Cur)) 2073 Cur = Cur->getParent(); 2074 if (!Cur->Encloses(DC)) { 2075 // The qualifying scope doesn't enclose the original declaration. 2076 // Emit diagnostic based on current scope. 2077 SourceLocation L = D.getIdentifierLoc(); 2078 SourceRange R = D.getCXXScopeSpec().getRange(); 2079 if (isa<FunctionDecl>(Cur)) 2080 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2081 else 2082 Diag(L, diag::err_invalid_declarator_scope) 2083 << Name << cast<NamedDecl>(DC) << R; 2084 D.setInvalidType(); 2085 } 2086 } 2087 } 2088 2089 if (Previous.isSingleResult() && 2090 Previous.getFoundDecl()->isTemplateParameter()) { 2091 // Maybe we will complain about the shadowed template parameter. 2092 if (!D.isInvalidType()) 2093 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2094 Previous.getFoundDecl())) 2095 D.setInvalidType(); 2096 2097 // Just pretend that we didn't see the previous declaration. 2098 Previous.clear(); 2099 } 2100 2101 // In C++, the previous declaration we find might be a tag type 2102 // (class or enum). In this case, the new declaration will hide the 2103 // tag type. Note that this does does not apply if we're declaring a 2104 // typedef (C++ [dcl.typedef]p4). 2105 if (Previous.isSingleTagDecl() && 2106 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2107 Previous.clear(); 2108 2109 bool Redeclaration = false; 2110 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2111 if (TemplateParamLists.size()) { 2112 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2113 return DeclPtrTy(); 2114 } 2115 2116 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2117 } else if (R->isFunctionType()) { 2118 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2119 move(TemplateParamLists), 2120 IsFunctionDefinition, Redeclaration); 2121 } else { 2122 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2123 move(TemplateParamLists), 2124 Redeclaration); 2125 } 2126 2127 if (New == 0) 2128 return DeclPtrTy(); 2129 2130 // If this has an identifier and is not an invalid redeclaration or 2131 // function template specialization, add it to the scope stack. 2132 if (Name && !(Redeclaration && New->isInvalidDecl())) 2133 PushOnScopeChains(New, S); 2134 2135 return DeclPtrTy::make(New); 2136} 2137 2138/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2139/// types into constant array types in certain situations which would otherwise 2140/// be errors (for GCC compatibility). 2141static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2142 ASTContext &Context, 2143 bool &SizeIsNegative) { 2144 // This method tries to turn a variable array into a constant 2145 // array even when the size isn't an ICE. This is necessary 2146 // for compatibility with code that depends on gcc's buggy 2147 // constant expression folding, like struct {char x[(int)(char*)2];} 2148 SizeIsNegative = false; 2149 2150 QualifierCollector Qs; 2151 const Type *Ty = Qs.strip(T); 2152 2153 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2154 QualType Pointee = PTy->getPointeeType(); 2155 QualType FixedType = 2156 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2157 if (FixedType.isNull()) return FixedType; 2158 FixedType = Context.getPointerType(FixedType); 2159 return Qs.apply(FixedType); 2160 } 2161 2162 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2163 if (!VLATy) 2164 return QualType(); 2165 // FIXME: We should probably handle this case 2166 if (VLATy->getElementType()->isVariablyModifiedType()) 2167 return QualType(); 2168 2169 Expr::EvalResult EvalResult; 2170 if (!VLATy->getSizeExpr() || 2171 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2172 !EvalResult.Val.isInt()) 2173 return QualType(); 2174 2175 llvm::APSInt &Res = EvalResult.Val.getInt(); 2176 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2177 // TODO: preserve the size expression in declarator info 2178 return Context.getConstantArrayType(VLATy->getElementType(), 2179 Res, ArrayType::Normal, 0); 2180 } 2181 2182 SizeIsNegative = true; 2183 return QualType(); 2184} 2185 2186/// \brief Register the given locally-scoped external C declaration so 2187/// that it can be found later for redeclarations 2188void 2189Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2190 const LookupResult &Previous, 2191 Scope *S) { 2192 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2193 "Decl is not a locally-scoped decl!"); 2194 // Note that we have a locally-scoped external with this name. 2195 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2196 2197 if (!Previous.isSingleResult()) 2198 return; 2199 2200 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2201 2202 // If there was a previous declaration of this variable, it may be 2203 // in our identifier chain. Update the identifier chain with the new 2204 // declaration. 2205 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2206 // The previous declaration was found on the identifer resolver 2207 // chain, so remove it from its scope. 2208 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2209 S = S->getParent(); 2210 2211 if (S) 2212 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2213 } 2214} 2215 2216/// \brief Diagnose function specifiers on a declaration of an identifier that 2217/// does not identify a function. 2218void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2219 // FIXME: We should probably indicate the identifier in question to avoid 2220 // confusion for constructs like "inline int a(), b;" 2221 if (D.getDeclSpec().isInlineSpecified()) 2222 Diag(D.getDeclSpec().getInlineSpecLoc(), 2223 diag::err_inline_non_function); 2224 2225 if (D.getDeclSpec().isVirtualSpecified()) 2226 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2227 diag::err_virtual_non_function); 2228 2229 if (D.getDeclSpec().isExplicitSpecified()) 2230 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2231 diag::err_explicit_non_function); 2232} 2233 2234NamedDecl* 2235Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2236 QualType R, TypeSourceInfo *TInfo, 2237 LookupResult &Previous, bool &Redeclaration) { 2238 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2239 if (D.getCXXScopeSpec().isSet()) { 2240 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2241 << D.getCXXScopeSpec().getRange(); 2242 D.setInvalidType(); 2243 // Pretend we didn't see the scope specifier. 2244 DC = CurContext; 2245 Previous.clear(); 2246 } 2247 2248 if (getLangOptions().CPlusPlus) { 2249 // Check that there are no default arguments (C++ only). 2250 CheckExtraCXXDefaultArguments(D); 2251 } 2252 2253 DiagnoseFunctionSpecifiers(D); 2254 2255 if (D.getDeclSpec().isThreadSpecified()) 2256 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2257 2258 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2259 if (!NewTD) return 0; 2260 2261 // Handle attributes prior to checking for duplicates in MergeVarDecl 2262 ProcessDeclAttributes(S, NewTD, D); 2263 2264 // Merge the decl with the existing one if appropriate. If the decl is 2265 // in an outer scope, it isn't the same thing. 2266 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2267 if (!Previous.empty()) { 2268 Redeclaration = true; 2269 MergeTypeDefDecl(NewTD, Previous); 2270 } 2271 2272 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2273 // then it shall have block scope. 2274 QualType T = NewTD->getUnderlyingType(); 2275 if (T->isVariablyModifiedType()) { 2276 FunctionNeedsScopeChecking() = true; 2277 2278 if (S->getFnParent() == 0) { 2279 bool SizeIsNegative; 2280 QualType FixedTy = 2281 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2282 if (!FixedTy.isNull()) { 2283 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2284 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2285 } else { 2286 if (SizeIsNegative) 2287 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2288 else if (T->isVariableArrayType()) 2289 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2290 else 2291 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2292 NewTD->setInvalidDecl(); 2293 } 2294 } 2295 } 2296 2297 // If this is the C FILE type, notify the AST context. 2298 if (IdentifierInfo *II = NewTD->getIdentifier()) 2299 if (!NewTD->isInvalidDecl() && 2300 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2301 if (II->isStr("FILE")) 2302 Context.setFILEDecl(NewTD); 2303 else if (II->isStr("jmp_buf")) 2304 Context.setjmp_bufDecl(NewTD); 2305 else if (II->isStr("sigjmp_buf")) 2306 Context.setsigjmp_bufDecl(NewTD); 2307 } 2308 2309 return NewTD; 2310} 2311 2312/// \brief Determines whether the given declaration is an out-of-scope 2313/// previous declaration. 2314/// 2315/// This routine should be invoked when name lookup has found a 2316/// previous declaration (PrevDecl) that is not in the scope where a 2317/// new declaration by the same name is being introduced. If the new 2318/// declaration occurs in a local scope, previous declarations with 2319/// linkage may still be considered previous declarations (C99 2320/// 6.2.2p4-5, C++ [basic.link]p6). 2321/// 2322/// \param PrevDecl the previous declaration found by name 2323/// lookup 2324/// 2325/// \param DC the context in which the new declaration is being 2326/// declared. 2327/// 2328/// \returns true if PrevDecl is an out-of-scope previous declaration 2329/// for a new delcaration with the same name. 2330static bool 2331isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2332 ASTContext &Context) { 2333 if (!PrevDecl) 2334 return 0; 2335 2336 if (!PrevDecl->hasLinkage()) 2337 return false; 2338 2339 if (Context.getLangOptions().CPlusPlus) { 2340 // C++ [basic.link]p6: 2341 // If there is a visible declaration of an entity with linkage 2342 // having the same name and type, ignoring entities declared 2343 // outside the innermost enclosing namespace scope, the block 2344 // scope declaration declares that same entity and receives the 2345 // linkage of the previous declaration. 2346 DeclContext *OuterContext = DC->getLookupContext(); 2347 if (!OuterContext->isFunctionOrMethod()) 2348 // This rule only applies to block-scope declarations. 2349 return false; 2350 else { 2351 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2352 if (PrevOuterContext->isRecord()) 2353 // We found a member function: ignore it. 2354 return false; 2355 else { 2356 // Find the innermost enclosing namespace for the new and 2357 // previous declarations. 2358 while (!OuterContext->isFileContext()) 2359 OuterContext = OuterContext->getParent(); 2360 while (!PrevOuterContext->isFileContext()) 2361 PrevOuterContext = PrevOuterContext->getParent(); 2362 2363 // The previous declaration is in a different namespace, so it 2364 // isn't the same function. 2365 if (OuterContext->getPrimaryContext() != 2366 PrevOuterContext->getPrimaryContext()) 2367 return false; 2368 } 2369 } 2370 } 2371 2372 return true; 2373} 2374 2375static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2376 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2377 if (!SS.isSet()) return; 2378 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2379 SS.getRange()); 2380} 2381 2382NamedDecl* 2383Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2384 QualType R, TypeSourceInfo *TInfo, 2385 LookupResult &Previous, 2386 MultiTemplateParamsArg TemplateParamLists, 2387 bool &Redeclaration) { 2388 DeclarationName Name = GetNameForDeclarator(D); 2389 2390 // Check that there are no default arguments (C++ only). 2391 if (getLangOptions().CPlusPlus) 2392 CheckExtraCXXDefaultArguments(D); 2393 2394 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2395 assert(SCSpec != DeclSpec::SCS_typedef && 2396 "Parser allowed 'typedef' as storage class VarDecl."); 2397 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 2398 if (SCSpec == DeclSpec::SCS_mutable) { 2399 // mutable can only appear on non-static class members, so it's always 2400 // an error here 2401 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2402 D.setInvalidType(); 2403 SC = VarDecl::None; 2404 } 2405 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2406 VarDecl::StorageClass SCAsWritten 2407 = StorageClassSpecToVarDeclStorageClass(SCSpec, DC); 2408 2409 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2410 if (!II) { 2411 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2412 << Name.getAsString(); 2413 return 0; 2414 } 2415 2416 DiagnoseFunctionSpecifiers(D); 2417 2418 if (!DC->isRecord() && S->getFnParent() == 0) { 2419 // C99 6.9p2: The storage-class specifiers auto and register shall not 2420 // appear in the declaration specifiers in an external declaration. 2421 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2422 2423 // If this is a register variable with an asm label specified, then this 2424 // is a GNU extension. 2425 if (SC == VarDecl::Register && D.getAsmLabel()) 2426 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2427 else 2428 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2429 D.setInvalidType(); 2430 } 2431 } 2432 if (DC->isRecord() && !CurContext->isRecord()) { 2433 // This is an out-of-line definition of a static data member. 2434 if (SC == VarDecl::Static) { 2435 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2436 diag::err_static_out_of_line) 2437 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2438 } else if (SC == VarDecl::None) 2439 SC = VarDecl::Static; 2440 } 2441 if (SC == VarDecl::Static) { 2442 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2443 if (RD->isLocalClass()) 2444 Diag(D.getIdentifierLoc(), 2445 diag::err_static_data_member_not_allowed_in_local_class) 2446 << Name << RD->getDeclName(); 2447 } 2448 } 2449 2450 // Match up the template parameter lists with the scope specifier, then 2451 // determine whether we have a template or a template specialization. 2452 bool isExplicitSpecialization = false; 2453 if (TemplateParameterList *TemplateParams 2454 = MatchTemplateParametersToScopeSpecifier( 2455 D.getDeclSpec().getSourceRange().getBegin(), 2456 D.getCXXScopeSpec(), 2457 (TemplateParameterList**)TemplateParamLists.get(), 2458 TemplateParamLists.size(), 2459 /*never a friend*/ false, 2460 isExplicitSpecialization)) { 2461 if (TemplateParams->size() > 0) { 2462 // There is no such thing as a variable template. 2463 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2464 << II 2465 << SourceRange(TemplateParams->getTemplateLoc(), 2466 TemplateParams->getRAngleLoc()); 2467 return 0; 2468 } else { 2469 // There is an extraneous 'template<>' for this variable. Complain 2470 // about it, but allow the declaration of the variable. 2471 Diag(TemplateParams->getTemplateLoc(), 2472 diag::err_template_variable_noparams) 2473 << II 2474 << SourceRange(TemplateParams->getTemplateLoc(), 2475 TemplateParams->getRAngleLoc()); 2476 2477 isExplicitSpecialization = true; 2478 } 2479 } 2480 2481 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2482 II, R, TInfo, SC, SCAsWritten); 2483 2484 if (D.isInvalidType()) 2485 NewVD->setInvalidDecl(); 2486 2487 SetNestedNameSpecifier(NewVD, D); 2488 2489 if (D.getDeclSpec().isThreadSpecified()) { 2490 if (NewVD->hasLocalStorage()) 2491 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2492 else if (!Context.Target.isTLSSupported()) 2493 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2494 else 2495 NewVD->setThreadSpecified(true); 2496 } 2497 2498 // Set the lexical context. If the declarator has a C++ scope specifier, the 2499 // lexical context will be different from the semantic context. 2500 NewVD->setLexicalDeclContext(CurContext); 2501 2502 // Handle attributes prior to checking for duplicates in MergeVarDecl 2503 ProcessDeclAttributes(S, NewVD, D); 2504 2505 // Handle GNU asm-label extension (encoded as an attribute). 2506 if (Expr *E = (Expr*) D.getAsmLabel()) { 2507 // The parser guarantees this is a string. 2508 StringLiteral *SE = cast<StringLiteral>(E); 2509 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2510 } 2511 2512 // Diagnose shadowed variables before filtering for scope. 2513 if (!D.getCXXScopeSpec().isSet()) 2514 CheckShadow(S, NewVD, Previous); 2515 2516 // Don't consider existing declarations that are in a different 2517 // scope and are out-of-semantic-context declarations (if the new 2518 // declaration has linkage). 2519 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2520 2521 // Merge the decl with the existing one if appropriate. 2522 if (!Previous.empty()) { 2523 if (Previous.isSingleResult() && 2524 isa<FieldDecl>(Previous.getFoundDecl()) && 2525 D.getCXXScopeSpec().isSet()) { 2526 // The user tried to define a non-static data member 2527 // out-of-line (C++ [dcl.meaning]p1). 2528 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2529 << D.getCXXScopeSpec().getRange(); 2530 Previous.clear(); 2531 NewVD->setInvalidDecl(); 2532 } 2533 } else if (D.getCXXScopeSpec().isSet()) { 2534 // No previous declaration in the qualifying scope. 2535 Diag(D.getIdentifierLoc(), diag::err_no_member) 2536 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2537 << D.getCXXScopeSpec().getRange(); 2538 NewVD->setInvalidDecl(); 2539 } 2540 2541 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2542 2543 // This is an explicit specialization of a static data member. Check it. 2544 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2545 CheckMemberSpecialization(NewVD, Previous)) 2546 NewVD->setInvalidDecl(); 2547 2548 // attributes declared post-definition are currently ignored 2549 if (Previous.isSingleResult()) { 2550 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2551 if (Def && (Def = Def->getDefinition()) && 2552 Def != NewVD && D.hasAttributes()) { 2553 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2554 Diag(Def->getLocation(), diag::note_previous_definition); 2555 } 2556 } 2557 2558 // If this is a locally-scoped extern C variable, update the map of 2559 // such variables. 2560 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2561 !NewVD->isInvalidDecl()) 2562 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2563 2564 return NewVD; 2565} 2566 2567/// \brief Diagnose variable or built-in function shadowing. Implements 2568/// -Wshadow. 2569/// 2570/// This method is called whenever a VarDecl is added to a "useful" 2571/// scope. 2572/// 2573/// \param S the scope in which the shadowing name is being declared 2574/// \param R the lookup of the name 2575/// 2576void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2577 // Return if warning is ignored. 2578 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2579 return; 2580 2581 // Don't diagnose declarations at file scope. The scope might not 2582 // have a DeclContext if (e.g.) we're parsing a function prototype. 2583 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2584 if (NewDC && NewDC->isFileContext()) 2585 return; 2586 2587 // Only diagnose if we're shadowing an unambiguous field or variable. 2588 if (R.getResultKind() != LookupResult::Found) 2589 return; 2590 2591 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2592 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2593 return; 2594 2595 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2596 2597 // Only warn about certain kinds of shadowing for class members. 2598 if (NewDC && NewDC->isRecord()) { 2599 // In particular, don't warn about shadowing non-class members. 2600 if (!OldDC->isRecord()) 2601 return; 2602 2603 // TODO: should we warn about static data members shadowing 2604 // static data members from base classes? 2605 2606 // TODO: don't diagnose for inaccessible shadowed members. 2607 // This is hard to do perfectly because we might friend the 2608 // shadowing context, but that's just a false negative. 2609 } 2610 2611 // Determine what kind of declaration we're shadowing. 2612 unsigned Kind; 2613 if (isa<RecordDecl>(OldDC)) { 2614 if (isa<FieldDecl>(ShadowedDecl)) 2615 Kind = 3; // field 2616 else 2617 Kind = 2; // static data member 2618 } else if (OldDC->isFileContext()) 2619 Kind = 1; // global 2620 else 2621 Kind = 0; // local 2622 2623 DeclarationName Name = R.getLookupName(); 2624 2625 // Emit warning and note. 2626 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2627 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2628} 2629 2630/// \brief Check -Wshadow without the advantage of a previous lookup. 2631void Sema::CheckShadow(Scope *S, VarDecl *D) { 2632 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2633 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2634 LookupName(R, S); 2635 CheckShadow(S, D, R); 2636} 2637 2638/// \brief Perform semantic checking on a newly-created variable 2639/// declaration. 2640/// 2641/// This routine performs all of the type-checking required for a 2642/// variable declaration once it has been built. It is used both to 2643/// check variables after they have been parsed and their declarators 2644/// have been translated into a declaration, and to check variables 2645/// that have been instantiated from a template. 2646/// 2647/// Sets NewVD->isInvalidDecl() if an error was encountered. 2648void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2649 LookupResult &Previous, 2650 bool &Redeclaration) { 2651 // If the decl is already known invalid, don't check it. 2652 if (NewVD->isInvalidDecl()) 2653 return; 2654 2655 QualType T = NewVD->getType(); 2656 2657 if (T->isObjCInterfaceType()) { 2658 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2659 return NewVD->setInvalidDecl(); 2660 } 2661 2662 // Emit an error if an address space was applied to decl with local storage. 2663 // This includes arrays of objects with address space qualifiers, but not 2664 // automatic variables that point to other address spaces. 2665 // ISO/IEC TR 18037 S5.1.2 2666 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2667 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2668 return NewVD->setInvalidDecl(); 2669 } 2670 2671 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2672 && !NewVD->hasAttr<BlocksAttr>()) 2673 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2674 2675 bool isVM = T->isVariablyModifiedType(); 2676 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2677 NewVD->hasAttr<BlocksAttr>() || 2678 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2679 // However, this turns on the scope checker for everything with a variable 2680 // which may impact compile time. See if we can find a better solution 2681 // to this, perhaps only checking functions that contain gotos in C++? 2682 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2683 FunctionNeedsScopeChecking() = true; 2684 2685 if ((isVM && NewVD->hasLinkage()) || 2686 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2687 bool SizeIsNegative; 2688 QualType FixedTy = 2689 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2690 2691 if (FixedTy.isNull() && T->isVariableArrayType()) { 2692 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2693 // FIXME: This won't give the correct result for 2694 // int a[10][n]; 2695 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2696 2697 if (NewVD->isFileVarDecl()) 2698 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2699 << SizeRange; 2700 else if (NewVD->getStorageClass() == VarDecl::Static) 2701 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2702 << SizeRange; 2703 else 2704 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2705 << SizeRange; 2706 return NewVD->setInvalidDecl(); 2707 } 2708 2709 if (FixedTy.isNull()) { 2710 if (NewVD->isFileVarDecl()) 2711 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2712 else 2713 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2714 return NewVD->setInvalidDecl(); 2715 } 2716 2717 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2718 NewVD->setType(FixedTy); 2719 } 2720 2721 if (Previous.empty() && NewVD->isExternC()) { 2722 // Since we did not find anything by this name and we're declaring 2723 // an extern "C" variable, look for a non-visible extern "C" 2724 // declaration with the same name. 2725 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2726 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2727 if (Pos != LocallyScopedExternalDecls.end()) 2728 Previous.addDecl(Pos->second); 2729 } 2730 2731 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2732 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2733 << T; 2734 return NewVD->setInvalidDecl(); 2735 } 2736 2737 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2738 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2739 return NewVD->setInvalidDecl(); 2740 } 2741 2742 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2743 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2744 return NewVD->setInvalidDecl(); 2745 } 2746 2747 if (!Previous.empty()) { 2748 Redeclaration = true; 2749 MergeVarDecl(NewVD, Previous); 2750 } 2751} 2752 2753/// \brief Data used with FindOverriddenMethod 2754struct FindOverriddenMethodData { 2755 Sema *S; 2756 CXXMethodDecl *Method; 2757}; 2758 2759/// \brief Member lookup function that determines whether a given C++ 2760/// method overrides a method in a base class, to be used with 2761/// CXXRecordDecl::lookupInBases(). 2762static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2763 CXXBasePath &Path, 2764 void *UserData) { 2765 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2766 2767 FindOverriddenMethodData *Data 2768 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2769 2770 DeclarationName Name = Data->Method->getDeclName(); 2771 2772 // FIXME: Do we care about other names here too? 2773 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2774 // We really want to find the base class constructor here. 2775 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2776 CanQualType CT = Data->S->Context.getCanonicalType(T); 2777 2778 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2779 } 2780 2781 for (Path.Decls = BaseRecord->lookup(Name); 2782 Path.Decls.first != Path.Decls.second; 2783 ++Path.Decls.first) { 2784 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2785 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2786 return true; 2787 } 2788 } 2789 2790 return false; 2791} 2792 2793/// AddOverriddenMethods - See if a method overrides any in the base classes, 2794/// and if so, check that it's a valid override and remember it. 2795void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2796 // Look for virtual methods in base classes that this method might override. 2797 CXXBasePaths Paths; 2798 FindOverriddenMethodData Data; 2799 Data.Method = MD; 2800 Data.S = this; 2801 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2802 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2803 E = Paths.found_decls_end(); I != E; ++I) { 2804 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2805 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2806 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2807 !CheckOverridingFunctionAttributes(MD, OldMD)) 2808 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2809 } 2810 } 2811 } 2812} 2813 2814NamedDecl* 2815Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2816 QualType R, TypeSourceInfo *TInfo, 2817 LookupResult &Previous, 2818 MultiTemplateParamsArg TemplateParamLists, 2819 bool IsFunctionDefinition, bool &Redeclaration) { 2820 assert(R.getTypePtr()->isFunctionType()); 2821 2822 DeclarationName Name = GetNameForDeclarator(D); 2823 FunctionDecl::StorageClass SC = FunctionDecl::None; 2824 switch (D.getDeclSpec().getStorageClassSpec()) { 2825 default: assert(0 && "Unknown storage class!"); 2826 case DeclSpec::SCS_auto: 2827 case DeclSpec::SCS_register: 2828 case DeclSpec::SCS_mutable: 2829 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2830 diag::err_typecheck_sclass_func); 2831 D.setInvalidType(); 2832 break; 2833 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2834 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2835 case DeclSpec::SCS_static: { 2836 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2837 // C99 6.7.1p5: 2838 // The declaration of an identifier for a function that has 2839 // block scope shall have no explicit storage-class specifier 2840 // other than extern 2841 // See also (C++ [dcl.stc]p4). 2842 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2843 diag::err_static_block_func); 2844 SC = FunctionDecl::None; 2845 } else 2846 SC = FunctionDecl::Static; 2847 break; 2848 } 2849 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2850 } 2851 2852 if (D.getDeclSpec().isThreadSpecified()) 2853 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2854 2855 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2856 bool isInline = D.getDeclSpec().isInlineSpecified(); 2857 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2858 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2859 2860 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2861 FunctionDecl::StorageClass SCAsWritten 2862 = StorageClassSpecToFunctionDeclStorageClass(SCSpec, DC); 2863 2864 // Check that the return type is not an abstract class type. 2865 // For record types, this is done by the AbstractClassUsageDiagnoser once 2866 // the class has been completely parsed. 2867 if (!DC->isRecord() && 2868 RequireNonAbstractType(D.getIdentifierLoc(), 2869 R->getAs<FunctionType>()->getResultType(), 2870 diag::err_abstract_type_in_decl, 2871 AbstractReturnType)) 2872 D.setInvalidType(); 2873 2874 // Do not allow returning a objc interface by-value. 2875 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2876 Diag(D.getIdentifierLoc(), 2877 diag::err_object_cannot_be_passed_returned_by_value) << 0 2878 << R->getAs<FunctionType>()->getResultType(); 2879 D.setInvalidType(); 2880 } 2881 2882 bool isVirtualOkay = false; 2883 FunctionDecl *NewFD; 2884 2885 if (isFriend) { 2886 // C++ [class.friend]p5 2887 // A function can be defined in a friend declaration of a 2888 // class . . . . Such a function is implicitly inline. 2889 isInline |= IsFunctionDefinition; 2890 } 2891 2892 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2893 // This is a C++ constructor declaration. 2894 assert(DC->isRecord() && 2895 "Constructors can only be declared in a member context"); 2896 2897 R = CheckConstructorDeclarator(D, R, SC); 2898 2899 // Create the new declaration 2900 NewFD = CXXConstructorDecl::Create(Context, 2901 cast<CXXRecordDecl>(DC), 2902 D.getIdentifierLoc(), Name, R, TInfo, 2903 isExplicit, isInline, 2904 /*isImplicitlyDeclared=*/false); 2905 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2906 // This is a C++ destructor declaration. 2907 if (DC->isRecord()) { 2908 R = CheckDestructorDeclarator(D, SC); 2909 2910 NewFD = CXXDestructorDecl::Create(Context, 2911 cast<CXXRecordDecl>(DC), 2912 D.getIdentifierLoc(), Name, R, 2913 isInline, 2914 /*isImplicitlyDeclared=*/false); 2915 NewFD->setTypeSourceInfo(TInfo); 2916 2917 isVirtualOkay = true; 2918 } else { 2919 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2920 2921 // Create a FunctionDecl to satisfy the function definition parsing 2922 // code path. 2923 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2924 Name, R, TInfo, SC, SCAsWritten, isInline, 2925 /*hasPrototype=*/true); 2926 D.setInvalidType(); 2927 } 2928 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2929 if (!DC->isRecord()) { 2930 Diag(D.getIdentifierLoc(), 2931 diag::err_conv_function_not_member); 2932 return 0; 2933 } 2934 2935 CheckConversionDeclarator(D, R, SC); 2936 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2937 D.getIdentifierLoc(), Name, R, TInfo, 2938 isInline, isExplicit); 2939 2940 isVirtualOkay = true; 2941 } else if (DC->isRecord()) { 2942 // If the of the function is the same as the name of the record, then this 2943 // must be an invalid constructor that has a return type. 2944 // (The parser checks for a return type and makes the declarator a 2945 // constructor if it has no return type). 2946 // must have an invalid constructor that has a return type 2947 if (Name.getAsIdentifierInfo() && 2948 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2949 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2950 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2951 << SourceRange(D.getIdentifierLoc()); 2952 return 0; 2953 } 2954 2955 bool isStatic = SC == FunctionDecl::Static; 2956 2957 // [class.free]p1: 2958 // Any allocation function for a class T is a static member 2959 // (even if not explicitly declared static). 2960 if (Name.getCXXOverloadedOperator() == OO_New || 2961 Name.getCXXOverloadedOperator() == OO_Array_New) 2962 isStatic = true; 2963 2964 // [class.free]p6 Any deallocation function for a class X is a static member 2965 // (even if not explicitly declared static). 2966 if (Name.getCXXOverloadedOperator() == OO_Delete || 2967 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2968 isStatic = true; 2969 2970 // This is a C++ method declaration. 2971 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2972 D.getIdentifierLoc(), Name, R, TInfo, 2973 isStatic, SCAsWritten, isInline); 2974 2975 isVirtualOkay = !isStatic; 2976 } else { 2977 // Determine whether the function was written with a 2978 // prototype. This true when: 2979 // - we're in C++ (where every function has a prototype), 2980 // - there is a prototype in the declarator, or 2981 // - the type R of the function is some kind of typedef or other reference 2982 // to a type name (which eventually refers to a function type). 2983 bool HasPrototype = 2984 getLangOptions().CPlusPlus || 2985 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2986 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2987 2988 NewFD = FunctionDecl::Create(Context, DC, 2989 D.getIdentifierLoc(), 2990 Name, R, TInfo, SC, SCAsWritten, isInline, 2991 HasPrototype); 2992 } 2993 2994 if (D.isInvalidType()) 2995 NewFD->setInvalidDecl(); 2996 2997 SetNestedNameSpecifier(NewFD, D); 2998 2999 // Set the lexical context. If the declarator has a C++ 3000 // scope specifier, or is the object of a friend declaration, the 3001 // lexical context will be different from the semantic context. 3002 NewFD->setLexicalDeclContext(CurContext); 3003 3004 // Match up the template parameter lists with the scope specifier, then 3005 // determine whether we have a template or a template specialization. 3006 FunctionTemplateDecl *FunctionTemplate = 0; 3007 bool isExplicitSpecialization = false; 3008 bool isFunctionTemplateSpecialization = false; 3009 if (TemplateParameterList *TemplateParams 3010 = MatchTemplateParametersToScopeSpecifier( 3011 D.getDeclSpec().getSourceRange().getBegin(), 3012 D.getCXXScopeSpec(), 3013 (TemplateParameterList**)TemplateParamLists.get(), 3014 TemplateParamLists.size(), 3015 isFriend, 3016 isExplicitSpecialization)) { 3017 if (TemplateParams->size() > 0) { 3018 // This is a function template 3019 3020 // Check that we can declare a template here. 3021 if (CheckTemplateDeclScope(S, TemplateParams)) 3022 return 0; 3023 3024 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3025 NewFD->getLocation(), 3026 Name, TemplateParams, 3027 NewFD); 3028 FunctionTemplate->setLexicalDeclContext(CurContext); 3029 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3030 } else { 3031 // This is a function template specialization. 3032 isFunctionTemplateSpecialization = true; 3033 3034 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3035 if (isFriend && isFunctionTemplateSpecialization) { 3036 // We want to remove the "template<>", found here. 3037 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3038 3039 // If we remove the template<> and the name is not a 3040 // template-id, we're actually silently creating a problem: 3041 // the friend declaration will refer to an untemplated decl, 3042 // and clearly the user wants a template specialization. So 3043 // we need to insert '<>' after the name. 3044 SourceLocation InsertLoc; 3045 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3046 InsertLoc = D.getName().getSourceRange().getEnd(); 3047 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3048 } 3049 3050 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3051 << Name << RemoveRange 3052 << FixItHint::CreateRemoval(RemoveRange) 3053 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3054 } 3055 } 3056 3057 // FIXME: Free this memory properly. 3058 TemplateParamLists.release(); 3059 } 3060 3061 // C++ [dcl.fct.spec]p5: 3062 // The virtual specifier shall only be used in declarations of 3063 // nonstatic class member functions that appear within a 3064 // member-specification of a class declaration; see 10.3. 3065 // 3066 if (isVirtual && !NewFD->isInvalidDecl()) { 3067 if (!isVirtualOkay) { 3068 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3069 diag::err_virtual_non_function); 3070 } else if (!CurContext->isRecord()) { 3071 // 'virtual' was specified outside of the class. 3072 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3073 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3074 } else { 3075 // Okay: Add virtual to the method. 3076 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3077 CurClass->setMethodAsVirtual(NewFD); 3078 } 3079 } 3080 3081 // C++ [dcl.fct.spec]p6: 3082 // The explicit specifier shall be used only in the declaration of a 3083 // constructor or conversion function within its class definition; see 12.3.1 3084 // and 12.3.2. 3085 if (isExplicit && !NewFD->isInvalidDecl()) { 3086 if (!CurContext->isRecord()) { 3087 // 'explicit' was specified outside of the class. 3088 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3089 diag::err_explicit_out_of_class) 3090 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3091 } else if (!isa<CXXConstructorDecl>(NewFD) && 3092 !isa<CXXConversionDecl>(NewFD)) { 3093 // 'explicit' was specified on a function that wasn't a constructor 3094 // or conversion function. 3095 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3096 diag::err_explicit_non_ctor_or_conv_function) 3097 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3098 } 3099 } 3100 3101 // Filter out previous declarations that don't match the scope. 3102 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3103 3104 if (isFriend) { 3105 // DC is the namespace in which the function is being declared. 3106 assert((DC->isFileContext() || !Previous.empty()) && 3107 "previously-undeclared friend function being created " 3108 "in a non-namespace context"); 3109 3110 // For now, claim that the objects have no previous declaration. 3111 if (FunctionTemplate) { 3112 FunctionTemplate->setObjectOfFriendDecl(false); 3113 FunctionTemplate->setAccess(AS_public); 3114 } 3115 NewFD->setObjectOfFriendDecl(false); 3116 NewFD->setAccess(AS_public); 3117 } 3118 3119 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3120 !CurContext->isRecord()) { 3121 // C++ [class.static]p1: 3122 // A data or function member of a class may be declared static 3123 // in a class definition, in which case it is a static member of 3124 // the class. 3125 3126 // Complain about the 'static' specifier if it's on an out-of-line 3127 // member function definition. 3128 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3129 diag::err_static_out_of_line) 3130 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3131 } 3132 3133 // Handle GNU asm-label extension (encoded as an attribute). 3134 if (Expr *E = (Expr*) D.getAsmLabel()) { 3135 // The parser guarantees this is a string. 3136 StringLiteral *SE = cast<StringLiteral>(E); 3137 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3138 } 3139 3140 // Copy the parameter declarations from the declarator D to the function 3141 // declaration NewFD, if they are available. First scavenge them into Params. 3142 llvm::SmallVector<ParmVarDecl*, 16> Params; 3143 if (D.getNumTypeObjects() > 0) { 3144 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3145 3146 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3147 // function that takes no arguments, not a function that takes a 3148 // single void argument. 3149 // We let through "const void" here because Sema::GetTypeForDeclarator 3150 // already checks for that case. 3151 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3152 FTI.ArgInfo[0].Param && 3153 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3154 // Empty arg list, don't push any params. 3155 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3156 3157 // In C++, the empty parameter-type-list must be spelled "void"; a 3158 // typedef of void is not permitted. 3159 if (getLangOptions().CPlusPlus && 3160 Param->getType().getUnqualifiedType() != Context.VoidTy) 3161 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3162 // FIXME: Leaks decl? 3163 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3164 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3165 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3166 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3167 Param->setDeclContext(NewFD); 3168 Params.push_back(Param); 3169 3170 if (Param->isInvalidDecl()) 3171 NewFD->setInvalidDecl(); 3172 } 3173 } 3174 3175 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3176 // When we're declaring a function with a typedef, typeof, etc as in the 3177 // following example, we'll need to synthesize (unnamed) 3178 // parameters for use in the declaration. 3179 // 3180 // @code 3181 // typedef void fn(int); 3182 // fn f; 3183 // @endcode 3184 3185 // Synthesize a parameter for each argument type. 3186 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3187 AE = FT->arg_type_end(); AI != AE; ++AI) { 3188 ParmVarDecl *Param = ParmVarDecl::Create(Context, NewFD, 3189 SourceLocation(), 0, 3190 *AI, /*TInfo=*/0, 3191 VarDecl::None, 3192 VarDecl::None, 0); 3193 Param->setImplicit(); 3194 Params.push_back(Param); 3195 } 3196 } else { 3197 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3198 "Should not need args for typedef of non-prototype fn"); 3199 } 3200 // Finally, we know we have the right number of parameters, install them. 3201 NewFD->setParams(Params.data(), Params.size()); 3202 3203 // If the declarator is a template-id, translate the parser's template 3204 // argument list into our AST format. 3205 bool HasExplicitTemplateArgs = false; 3206 TemplateArgumentListInfo TemplateArgs; 3207 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3208 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3209 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3210 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3211 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3212 TemplateId->getTemplateArgs(), 3213 TemplateId->NumArgs); 3214 translateTemplateArguments(TemplateArgsPtr, 3215 TemplateArgs); 3216 TemplateArgsPtr.release(); 3217 3218 HasExplicitTemplateArgs = true; 3219 3220 if (FunctionTemplate) { 3221 // FIXME: Diagnose function template with explicit template 3222 // arguments. 3223 HasExplicitTemplateArgs = false; 3224 } else if (!isFunctionTemplateSpecialization && 3225 !D.getDeclSpec().isFriendSpecified()) { 3226 // We have encountered something that the user meant to be a 3227 // specialization (because it has explicitly-specified template 3228 // arguments) but that was not introduced with a "template<>" (or had 3229 // too few of them). 3230 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3231 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3232 << FixItHint::CreateInsertion( 3233 D.getDeclSpec().getSourceRange().getBegin(), 3234 "template<> "); 3235 isFunctionTemplateSpecialization = true; 3236 } else { 3237 // "friend void foo<>(int);" is an implicit specialization decl. 3238 isFunctionTemplateSpecialization = true; 3239 } 3240 } else if (isFriend && isFunctionTemplateSpecialization) { 3241 // This combination is only possible in a recovery case; the user 3242 // wrote something like: 3243 // template <> friend void foo(int); 3244 // which we're recovering from as if the user had written: 3245 // friend void foo<>(int); 3246 // Go ahead and fake up a template id. 3247 HasExplicitTemplateArgs = true; 3248 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3249 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3250 } 3251 3252 // If it's a friend (and only if it's a friend), it's possible 3253 // that either the specialized function type or the specialized 3254 // template is dependent, and therefore matching will fail. In 3255 // this case, don't check the specialization yet. 3256 if (isFunctionTemplateSpecialization && isFriend && 3257 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3258 assert(HasExplicitTemplateArgs && 3259 "friend function specialization without template args"); 3260 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3261 Previous)) 3262 NewFD->setInvalidDecl(); 3263 } else if (isFunctionTemplateSpecialization) { 3264 if (CheckFunctionTemplateSpecialization(NewFD, 3265 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3266 Previous)) 3267 NewFD->setInvalidDecl(); 3268 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3269 if (CheckMemberSpecialization(NewFD, Previous)) 3270 NewFD->setInvalidDecl(); 3271 } 3272 3273 // Perform semantic checking on the function declaration. 3274 bool OverloadableAttrRequired = false; // FIXME: HACK! 3275 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3276 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3277 3278 assert((NewFD->isInvalidDecl() || !Redeclaration || 3279 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3280 "previous declaration set still overloaded"); 3281 3282 NamedDecl *PrincipalDecl = (FunctionTemplate 3283 ? cast<NamedDecl>(FunctionTemplate) 3284 : NewFD); 3285 3286 if (isFriend && Redeclaration) { 3287 AccessSpecifier Access = AS_public; 3288 if (!NewFD->isInvalidDecl()) 3289 Access = NewFD->getPreviousDeclaration()->getAccess(); 3290 3291 NewFD->setAccess(Access); 3292 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3293 3294 PrincipalDecl->setObjectOfFriendDecl(true); 3295 } 3296 3297 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3298 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3299 PrincipalDecl->setNonMemberOperator(); 3300 3301 // If we have a function template, check the template parameter 3302 // list. This will check and merge default template arguments. 3303 if (FunctionTemplate) { 3304 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3305 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3306 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3307 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3308 : TPC_FunctionTemplate); 3309 } 3310 3311 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3312 // Fake up an access specifier if it's supposed to be a class member. 3313 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3314 NewFD->setAccess(AS_public); 3315 3316 // An out-of-line member function declaration must also be a 3317 // definition (C++ [dcl.meaning]p1). 3318 // Note that this is not the case for explicit specializations of 3319 // function templates or member functions of class templates, per 3320 // C++ [temp.expl.spec]p2. 3321 if (!IsFunctionDefinition && !isFriend && 3322 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3323 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3324 << D.getCXXScopeSpec().getRange(); 3325 NewFD->setInvalidDecl(); 3326 } else if (!Redeclaration && 3327 !(isFriend && CurContext->isDependentContext())) { 3328 // The user tried to provide an out-of-line definition for a 3329 // function that is a member of a class or namespace, but there 3330 // was no such member function declared (C++ [class.mfct]p2, 3331 // C++ [namespace.memdef]p2). For example: 3332 // 3333 // class X { 3334 // void f() const; 3335 // }; 3336 // 3337 // void X::f() { } // ill-formed 3338 // 3339 // Complain about this problem, and attempt to suggest close 3340 // matches (e.g., those that differ only in cv-qualifiers and 3341 // whether the parameter types are references). 3342 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3343 << Name << DC << D.getCXXScopeSpec().getRange(); 3344 NewFD->setInvalidDecl(); 3345 3346 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3347 ForRedeclaration); 3348 LookupQualifiedName(Prev, DC); 3349 assert(!Prev.isAmbiguous() && 3350 "Cannot have an ambiguity in previous-declaration lookup"); 3351 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3352 Func != FuncEnd; ++Func) { 3353 if (isa<FunctionDecl>(*Func) && 3354 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3355 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3356 } 3357 } 3358 } 3359 3360 // Handle attributes. We need to have merged decls when handling attributes 3361 // (for example to check for conflicts, etc). 3362 // FIXME: This needs to happen before we merge declarations. Then, 3363 // let attribute merging cope with attribute conflicts. 3364 ProcessDeclAttributes(S, NewFD, D); 3365 3366 // attributes declared post-definition are currently ignored 3367 if (Redeclaration && Previous.isSingleResult()) { 3368 const FunctionDecl *Def; 3369 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3370 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3371 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3372 Diag(Def->getLocation(), diag::note_previous_definition); 3373 } 3374 } 3375 3376 AddKnownFunctionAttributes(NewFD); 3377 3378 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3379 // If a function name is overloadable in C, then every function 3380 // with that name must be marked "overloadable". 3381 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3382 << Redeclaration << NewFD; 3383 if (!Previous.empty()) 3384 Diag(Previous.getRepresentativeDecl()->getLocation(), 3385 diag::note_attribute_overloadable_prev_overload); 3386 NewFD->addAttr(::new (Context) OverloadableAttr()); 3387 } 3388 3389 // If this is a locally-scoped extern C function, update the 3390 // map of such names. 3391 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3392 && !NewFD->isInvalidDecl()) 3393 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3394 3395 // Set this FunctionDecl's range up to the right paren. 3396 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3397 3398 if (FunctionTemplate && NewFD->isInvalidDecl()) 3399 FunctionTemplate->setInvalidDecl(); 3400 3401 if (FunctionTemplate) 3402 return FunctionTemplate; 3403 3404 3405 // Keep track of static, non-inlined function definitions that 3406 // have not been used. We will warn later. 3407 // FIXME: Also include static functions declared but not defined. 3408 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3409 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3410 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3411 && !NewFD->hasAttr<ConstructorAttr>() 3412 && !NewFD->hasAttr<DestructorAttr>()) 3413 UnusedStaticFuncs.push_back(NewFD); 3414 3415 return NewFD; 3416} 3417 3418/// \brief Perform semantic checking of a new function declaration. 3419/// 3420/// Performs semantic analysis of the new function declaration 3421/// NewFD. This routine performs all semantic checking that does not 3422/// require the actual declarator involved in the declaration, and is 3423/// used both for the declaration of functions as they are parsed 3424/// (called via ActOnDeclarator) and for the declaration of functions 3425/// that have been instantiated via C++ template instantiation (called 3426/// via InstantiateDecl). 3427/// 3428/// \param IsExplicitSpecialiation whether this new function declaration is 3429/// an explicit specialization of the previous declaration. 3430/// 3431/// This sets NewFD->isInvalidDecl() to true if there was an error. 3432void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3433 LookupResult &Previous, 3434 bool IsExplicitSpecialization, 3435 bool &Redeclaration, 3436 bool &OverloadableAttrRequired) { 3437 // If NewFD is already known erroneous, don't do any of this checking. 3438 if (NewFD->isInvalidDecl()) 3439 return; 3440 3441 if (NewFD->getResultType()->isVariablyModifiedType()) { 3442 // Functions returning a variably modified type violate C99 6.7.5.2p2 3443 // because all functions have linkage. 3444 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3445 return NewFD->setInvalidDecl(); 3446 } 3447 3448 if (NewFD->isMain()) 3449 CheckMain(NewFD); 3450 3451 // Check for a previous declaration of this name. 3452 if (Previous.empty() && NewFD->isExternC()) { 3453 // Since we did not find anything by this name and we're declaring 3454 // an extern "C" function, look for a non-visible extern "C" 3455 // declaration with the same name. 3456 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3457 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3458 if (Pos != LocallyScopedExternalDecls.end()) 3459 Previous.addDecl(Pos->second); 3460 } 3461 3462 // Merge or overload the declaration with an existing declaration of 3463 // the same name, if appropriate. 3464 if (!Previous.empty()) { 3465 // Determine whether NewFD is an overload of PrevDecl or 3466 // a declaration that requires merging. If it's an overload, 3467 // there's no more work to do here; we'll just add the new 3468 // function to the scope. 3469 3470 NamedDecl *OldDecl = 0; 3471 if (!AllowOverloadingOfFunction(Previous, Context)) { 3472 Redeclaration = true; 3473 OldDecl = Previous.getFoundDecl(); 3474 } else { 3475 if (!getLangOptions().CPlusPlus) { 3476 OverloadableAttrRequired = true; 3477 3478 // Functions marked "overloadable" must have a prototype (that 3479 // we can't get through declaration merging). 3480 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3481 Diag(NewFD->getLocation(), 3482 diag::err_attribute_overloadable_no_prototype) 3483 << NewFD; 3484 Redeclaration = true; 3485 3486 // Turn this into a variadic function with no parameters. 3487 QualType R = Context.getFunctionType( 3488 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3489 0, 0, true, 0, false, false, 0, 0, 3490 FunctionType::ExtInfo()); 3491 NewFD->setType(R); 3492 return NewFD->setInvalidDecl(); 3493 } 3494 } 3495 3496 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3497 case Ovl_Match: 3498 Redeclaration = true; 3499 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3500 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3501 Redeclaration = false; 3502 } 3503 break; 3504 3505 case Ovl_NonFunction: 3506 Redeclaration = true; 3507 break; 3508 3509 case Ovl_Overload: 3510 Redeclaration = false; 3511 break; 3512 } 3513 } 3514 3515 if (Redeclaration) { 3516 // NewFD and OldDecl represent declarations that need to be 3517 // merged. 3518 if (MergeFunctionDecl(NewFD, OldDecl)) 3519 return NewFD->setInvalidDecl(); 3520 3521 Previous.clear(); 3522 Previous.addDecl(OldDecl); 3523 3524 if (FunctionTemplateDecl *OldTemplateDecl 3525 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3526 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3527 FunctionTemplateDecl *NewTemplateDecl 3528 = NewFD->getDescribedFunctionTemplate(); 3529 assert(NewTemplateDecl && "Template/non-template mismatch"); 3530 if (CXXMethodDecl *Method 3531 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3532 Method->setAccess(OldTemplateDecl->getAccess()); 3533 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3534 } 3535 3536 // If this is an explicit specialization of a member that is a function 3537 // template, mark it as a member specialization. 3538 if (IsExplicitSpecialization && 3539 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3540 NewTemplateDecl->setMemberSpecialization(); 3541 assert(OldTemplateDecl->isMemberSpecialization()); 3542 } 3543 } else { 3544 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3545 NewFD->setAccess(OldDecl->getAccess()); 3546 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3547 } 3548 } 3549 } 3550 3551 // Semantic checking for this function declaration (in isolation). 3552 if (getLangOptions().CPlusPlus) { 3553 // C++-specific checks. 3554 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3555 CheckConstructor(Constructor); 3556 } else if (CXXDestructorDecl *Destructor = 3557 dyn_cast<CXXDestructorDecl>(NewFD)) { 3558 CXXRecordDecl *Record = Destructor->getParent(); 3559 QualType ClassType = Context.getTypeDeclType(Record); 3560 3561 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3562 // type is dependent? Both gcc and edg can handle that. 3563 if (!ClassType->isDependentType()) { 3564 DeclarationName Name 3565 = Context.DeclarationNames.getCXXDestructorName( 3566 Context.getCanonicalType(ClassType)); 3567 if (NewFD->getDeclName() != Name) { 3568 Diag(NewFD->getLocation(), diag::err_destructor_name); 3569 return NewFD->setInvalidDecl(); 3570 } 3571 } 3572 3573 Record->setUserDeclaredDestructor(true); 3574 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3575 // user-defined destructor. 3576 Record->setPOD(false); 3577 3578 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3579 // declared destructor. 3580 // FIXME: C++0x: don't do this for "= default" destructors 3581 Record->setHasTrivialDestructor(false); 3582 } else if (CXXConversionDecl *Conversion 3583 = dyn_cast<CXXConversionDecl>(NewFD)) { 3584 ActOnConversionDeclarator(Conversion); 3585 } 3586 3587 // Find any virtual functions that this function overrides. 3588 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3589 if (!Method->isFunctionTemplateSpecialization() && 3590 !Method->getDescribedFunctionTemplate()) 3591 AddOverriddenMethods(Method->getParent(), Method); 3592 } 3593 3594 // Additional checks for the destructor; make sure we do this after we 3595 // figure out whether the destructor is virtual. 3596 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3597 if (!Destructor->getParent()->isDependentType()) 3598 CheckDestructor(Destructor); 3599 3600 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3601 if (NewFD->isOverloadedOperator() && 3602 CheckOverloadedOperatorDeclaration(NewFD)) 3603 return NewFD->setInvalidDecl(); 3604 3605 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3606 if (NewFD->getLiteralIdentifier() && 3607 CheckLiteralOperatorDeclaration(NewFD)) 3608 return NewFD->setInvalidDecl(); 3609 3610 // In C++, check default arguments now that we have merged decls. Unless 3611 // the lexical context is the class, because in this case this is done 3612 // during delayed parsing anyway. 3613 if (!CurContext->isRecord()) 3614 CheckCXXDefaultArguments(NewFD); 3615 } 3616} 3617 3618void Sema::CheckMain(FunctionDecl* FD) { 3619 // C++ [basic.start.main]p3: A program that declares main to be inline 3620 // or static is ill-formed. 3621 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3622 // shall not appear in a declaration of main. 3623 // static main is not an error under C99, but we should warn about it. 3624 bool isInline = FD->isInlineSpecified(); 3625 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3626 if (isInline || isStatic) { 3627 unsigned diagID = diag::warn_unusual_main_decl; 3628 if (isInline || getLangOptions().CPlusPlus) 3629 diagID = diag::err_unusual_main_decl; 3630 3631 int which = isStatic + (isInline << 1) - 1; 3632 Diag(FD->getLocation(), diagID) << which; 3633 } 3634 3635 QualType T = FD->getType(); 3636 assert(T->isFunctionType() && "function decl is not of function type"); 3637 const FunctionType* FT = T->getAs<FunctionType>(); 3638 3639 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3640 // TODO: add a replacement fixit to turn the return type into 'int'. 3641 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3642 FD->setInvalidDecl(true); 3643 } 3644 3645 // Treat protoless main() as nullary. 3646 if (isa<FunctionNoProtoType>(FT)) return; 3647 3648 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3649 unsigned nparams = FTP->getNumArgs(); 3650 assert(FD->getNumParams() == nparams); 3651 3652 bool HasExtraParameters = (nparams > 3); 3653 3654 // Darwin passes an undocumented fourth argument of type char**. If 3655 // other platforms start sprouting these, the logic below will start 3656 // getting shifty. 3657 if (nparams == 4 && 3658 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3659 HasExtraParameters = false; 3660 3661 if (HasExtraParameters) { 3662 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3663 FD->setInvalidDecl(true); 3664 nparams = 3; 3665 } 3666 3667 // FIXME: a lot of the following diagnostics would be improved 3668 // if we had some location information about types. 3669 3670 QualType CharPP = 3671 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3672 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3673 3674 for (unsigned i = 0; i < nparams; ++i) { 3675 QualType AT = FTP->getArgType(i); 3676 3677 bool mismatch = true; 3678 3679 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3680 mismatch = false; 3681 else if (Expected[i] == CharPP) { 3682 // As an extension, the following forms are okay: 3683 // char const ** 3684 // char const * const * 3685 // char * const * 3686 3687 QualifierCollector qs; 3688 const PointerType* PT; 3689 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3690 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3691 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3692 qs.removeConst(); 3693 mismatch = !qs.empty(); 3694 } 3695 } 3696 3697 if (mismatch) { 3698 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3699 // TODO: suggest replacing given type with expected type 3700 FD->setInvalidDecl(true); 3701 } 3702 } 3703 3704 if (nparams == 1 && !FD->isInvalidDecl()) { 3705 Diag(FD->getLocation(), diag::warn_main_one_arg); 3706 } 3707} 3708 3709bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3710 // FIXME: Need strict checking. In C89, we need to check for 3711 // any assignment, increment, decrement, function-calls, or 3712 // commas outside of a sizeof. In C99, it's the same list, 3713 // except that the aforementioned are allowed in unevaluated 3714 // expressions. Everything else falls under the 3715 // "may accept other forms of constant expressions" exception. 3716 // (We never end up here for C++, so the constant expression 3717 // rules there don't matter.) 3718 if (Init->isConstantInitializer(Context)) 3719 return false; 3720 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3721 << Init->getSourceRange(); 3722 return true; 3723} 3724 3725void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3726 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3727} 3728 3729/// AddInitializerToDecl - Adds the initializer Init to the 3730/// declaration dcl. If DirectInit is true, this is C++ direct 3731/// initialization rather than copy initialization. 3732void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3733 Decl *RealDecl = dcl.getAs<Decl>(); 3734 // If there is no declaration, there was an error parsing it. Just ignore 3735 // the initializer. 3736 if (RealDecl == 0) 3737 return; 3738 3739 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3740 // With declarators parsed the way they are, the parser cannot 3741 // distinguish between a normal initializer and a pure-specifier. 3742 // Thus this grotesque test. 3743 IntegerLiteral *IL; 3744 Expr *Init = static_cast<Expr *>(init.get()); 3745 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3746 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3747 CheckPureMethod(Method, Init->getSourceRange()); 3748 else { 3749 Diag(Method->getLocation(), diag::err_member_function_initialization) 3750 << Method->getDeclName() << Init->getSourceRange(); 3751 Method->setInvalidDecl(); 3752 } 3753 return; 3754 } 3755 3756 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3757 if (!VDecl) { 3758 if (getLangOptions().CPlusPlus && 3759 RealDecl->getLexicalDeclContext()->isRecord() && 3760 isa<NamedDecl>(RealDecl)) 3761 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3762 << cast<NamedDecl>(RealDecl)->getDeclName(); 3763 else 3764 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3765 RealDecl->setInvalidDecl(); 3766 return; 3767 } 3768 3769 // A definition must end up with a complete type, which means it must be 3770 // complete with the restriction that an array type might be completed by the 3771 // initializer; note that later code assumes this restriction. 3772 QualType BaseDeclType = VDecl->getType(); 3773 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3774 BaseDeclType = Array->getElementType(); 3775 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3776 diag::err_typecheck_decl_incomplete_type)) { 3777 RealDecl->setInvalidDecl(); 3778 return; 3779 } 3780 3781 // The variable can not have an abstract class type. 3782 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3783 diag::err_abstract_type_in_decl, 3784 AbstractVariableType)) 3785 VDecl->setInvalidDecl(); 3786 3787 const VarDecl *Def; 3788 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3789 Diag(VDecl->getLocation(), diag::err_redefinition) 3790 << VDecl->getDeclName(); 3791 Diag(Def->getLocation(), diag::note_previous_definition); 3792 VDecl->setInvalidDecl(); 3793 return; 3794 } 3795 3796 // Take ownership of the expression, now that we're sure we have somewhere 3797 // to put it. 3798 Expr *Init = init.takeAs<Expr>(); 3799 assert(Init && "missing initializer"); 3800 3801 // Capture the variable that is being initialized and the style of 3802 // initialization. 3803 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3804 3805 // FIXME: Poor source location information. 3806 InitializationKind Kind 3807 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3808 Init->getLocStart(), 3809 Init->getLocEnd()) 3810 : InitializationKind::CreateCopy(VDecl->getLocation(), 3811 Init->getLocStart()); 3812 3813 // Get the decls type and save a reference for later, since 3814 // CheckInitializerTypes may change it. 3815 QualType DclT = VDecl->getType(), SavT = DclT; 3816 if (VDecl->isBlockVarDecl()) { 3817 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3818 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3819 VDecl->setInvalidDecl(); 3820 } else if (!VDecl->isInvalidDecl()) { 3821 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3822 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3823 MultiExprArg(*this, (void**)&Init, 1), 3824 &DclT); 3825 if (Result.isInvalid()) { 3826 VDecl->setInvalidDecl(); 3827 return; 3828 } 3829 3830 Init = Result.takeAs<Expr>(); 3831 3832 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3833 // Don't check invalid declarations to avoid emitting useless diagnostics. 3834 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3835 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3836 CheckForConstantInitializer(Init, DclT); 3837 } 3838 } 3839 } else if (VDecl->isStaticDataMember() && 3840 VDecl->getLexicalDeclContext()->isRecord()) { 3841 // This is an in-class initialization for a static data member, e.g., 3842 // 3843 // struct S { 3844 // static const int value = 17; 3845 // }; 3846 3847 // Attach the initializer 3848 VDecl->setInit(Init); 3849 3850 // C++ [class.mem]p4: 3851 // A member-declarator can contain a constant-initializer only 3852 // if it declares a static member (9.4) of const integral or 3853 // const enumeration type, see 9.4.2. 3854 QualType T = VDecl->getType(); 3855 if (!T->isDependentType() && 3856 (!Context.getCanonicalType(T).isConstQualified() || 3857 !T->isIntegralType())) { 3858 Diag(VDecl->getLocation(), diag::err_member_initialization) 3859 << VDecl->getDeclName() << Init->getSourceRange(); 3860 VDecl->setInvalidDecl(); 3861 } else { 3862 // C++ [class.static.data]p4: 3863 // If a static data member is of const integral or const 3864 // enumeration type, its declaration in the class definition 3865 // can specify a constant-initializer which shall be an 3866 // integral constant expression (5.19). 3867 if (!Init->isTypeDependent() && 3868 !Init->getType()->isIntegralType()) { 3869 // We have a non-dependent, non-integral or enumeration type. 3870 Diag(Init->getSourceRange().getBegin(), 3871 diag::err_in_class_initializer_non_integral_type) 3872 << Init->getType() << Init->getSourceRange(); 3873 VDecl->setInvalidDecl(); 3874 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3875 // Check whether the expression is a constant expression. 3876 llvm::APSInt Value; 3877 SourceLocation Loc; 3878 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3879 Diag(Loc, diag::err_in_class_initializer_non_constant) 3880 << Init->getSourceRange(); 3881 VDecl->setInvalidDecl(); 3882 } else if (!VDecl->getType()->isDependentType()) 3883 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3884 } 3885 } 3886 } else if (VDecl->isFileVarDecl()) { 3887 if (VDecl->getStorageClass() == VarDecl::Extern && 3888 (!getLangOptions().CPlusPlus || 3889 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 3890 Diag(VDecl->getLocation(), diag::warn_extern_init); 3891 if (!VDecl->isInvalidDecl()) { 3892 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3893 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3894 MultiExprArg(*this, (void**)&Init, 1), 3895 &DclT); 3896 if (Result.isInvalid()) { 3897 VDecl->setInvalidDecl(); 3898 return; 3899 } 3900 3901 Init = Result.takeAs<Expr>(); 3902 } 3903 3904 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3905 // Don't check invalid declarations to avoid emitting useless diagnostics. 3906 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3907 // C99 6.7.8p4. All file scoped initializers need to be constant. 3908 CheckForConstantInitializer(Init, DclT); 3909 } 3910 } 3911 // If the type changed, it means we had an incomplete type that was 3912 // completed by the initializer. For example: 3913 // int ary[] = { 1, 3, 5 }; 3914 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3915 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3916 VDecl->setType(DclT); 3917 Init->setType(DclT); 3918 } 3919 3920 Init = MaybeCreateCXXExprWithTemporaries(Init); 3921 // Attach the initializer to the decl. 3922 VDecl->setInit(Init); 3923 3924 if (getLangOptions().CPlusPlus) { 3925 // Make sure we mark the destructor as used if necessary. 3926 QualType InitType = VDecl->getType(); 3927 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3928 InitType = Context.getBaseElementType(Array); 3929 if (const RecordType *Record = InitType->getAs<RecordType>()) 3930 FinalizeVarWithDestructor(VDecl, Record); 3931 } 3932 3933 return; 3934} 3935 3936/// ActOnInitializerError - Given that there was an error parsing an 3937/// initializer for the given declaration, try to return to some form 3938/// of sanity. 3939void Sema::ActOnInitializerError(DeclPtrTy dcl) { 3940 // Our main concern here is re-establishing invariants like "a 3941 // variable's type is either dependent or complete". 3942 Decl *D = dcl.getAs<Decl>(); 3943 if (!D || D->isInvalidDecl()) return; 3944 3945 VarDecl *VD = dyn_cast<VarDecl>(D); 3946 if (!VD) return; 3947 3948 QualType Ty = VD->getType(); 3949 if (Ty->isDependentType()) return; 3950 3951 // Require a complete type. 3952 if (RequireCompleteType(VD->getLocation(), 3953 Context.getBaseElementType(Ty), 3954 diag::err_typecheck_decl_incomplete_type)) { 3955 VD->setInvalidDecl(); 3956 return; 3957 } 3958 3959 // Require an abstract type. 3960 if (RequireNonAbstractType(VD->getLocation(), Ty, 3961 diag::err_abstract_type_in_decl, 3962 AbstractVariableType)) { 3963 VD->setInvalidDecl(); 3964 return; 3965 } 3966 3967 // Don't bother complaining about constructors or destructors, 3968 // though. 3969} 3970 3971void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3972 bool TypeContainsUndeducedAuto) { 3973 Decl *RealDecl = dcl.getAs<Decl>(); 3974 3975 // If there is no declaration, there was an error parsing it. Just ignore it. 3976 if (RealDecl == 0) 3977 return; 3978 3979 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3980 QualType Type = Var->getType(); 3981 3982 // C++0x [dcl.spec.auto]p3 3983 if (TypeContainsUndeducedAuto) { 3984 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3985 << Var->getDeclName() << Type; 3986 Var->setInvalidDecl(); 3987 return; 3988 } 3989 3990 switch (Var->isThisDeclarationADefinition()) { 3991 case VarDecl::Definition: 3992 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 3993 break; 3994 3995 // We have an out-of-line definition of a static data member 3996 // that has an in-class initializer, so we type-check this like 3997 // a declaration. 3998 // 3999 // Fall through 4000 4001 case VarDecl::DeclarationOnly: 4002 // It's only a declaration. 4003 4004 // Block scope. C99 6.7p7: If an identifier for an object is 4005 // declared with no linkage (C99 6.2.2p6), the type for the 4006 // object shall be complete. 4007 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4008 !Var->getLinkage() && !Var->isInvalidDecl() && 4009 RequireCompleteType(Var->getLocation(), Type, 4010 diag::err_typecheck_decl_incomplete_type)) 4011 Var->setInvalidDecl(); 4012 4013 // Make sure that the type is not abstract. 4014 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4015 RequireNonAbstractType(Var->getLocation(), Type, 4016 diag::err_abstract_type_in_decl, 4017 AbstractVariableType)) 4018 Var->setInvalidDecl(); 4019 return; 4020 4021 case VarDecl::TentativeDefinition: 4022 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4023 // object that has file scope without an initializer, and without a 4024 // storage-class specifier or with the storage-class specifier "static", 4025 // constitutes a tentative definition. Note: A tentative definition with 4026 // external linkage is valid (C99 6.2.2p5). 4027 if (!Var->isInvalidDecl()) { 4028 if (const IncompleteArrayType *ArrayT 4029 = Context.getAsIncompleteArrayType(Type)) { 4030 if (RequireCompleteType(Var->getLocation(), 4031 ArrayT->getElementType(), 4032 diag::err_illegal_decl_array_incomplete_type)) 4033 Var->setInvalidDecl(); 4034 } else if (Var->getStorageClass() == VarDecl::Static) { 4035 // C99 6.9.2p3: If the declaration of an identifier for an object is 4036 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4037 // declared type shall not be an incomplete type. 4038 // NOTE: code such as the following 4039 // static struct s; 4040 // struct s { int a; }; 4041 // is accepted by gcc. Hence here we issue a warning instead of 4042 // an error and we do not invalidate the static declaration. 4043 // NOTE: to avoid multiple warnings, only check the first declaration. 4044 if (Var->getPreviousDeclaration() == 0) 4045 RequireCompleteType(Var->getLocation(), Type, 4046 diag::ext_typecheck_decl_incomplete_type); 4047 } 4048 } 4049 4050 // Record the tentative definition; we're done. 4051 if (!Var->isInvalidDecl()) 4052 TentativeDefinitions.push_back(Var); 4053 return; 4054 } 4055 4056 // Provide a specific diagnostic for uninitialized variable 4057 // definitions with incomplete array type. 4058 if (Type->isIncompleteArrayType()) { 4059 Diag(Var->getLocation(), 4060 diag::err_typecheck_incomplete_array_needs_initializer); 4061 Var->setInvalidDecl(); 4062 return; 4063 } 4064 4065 // Provide a specific diagnostic for uninitialized variable 4066 // definitions with reference type. 4067 if (Type->isReferenceType()) { 4068 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4069 << Var->getDeclName() 4070 << SourceRange(Var->getLocation(), Var->getLocation()); 4071 Var->setInvalidDecl(); 4072 return; 4073 } 4074 4075 // Do not attempt to type-check the default initializer for a 4076 // variable with dependent type. 4077 if (Type->isDependentType()) 4078 return; 4079 4080 if (Var->isInvalidDecl()) 4081 return; 4082 4083 if (RequireCompleteType(Var->getLocation(), 4084 Context.getBaseElementType(Type), 4085 diag::err_typecheck_decl_incomplete_type)) { 4086 Var->setInvalidDecl(); 4087 return; 4088 } 4089 4090 // The variable can not have an abstract class type. 4091 if (RequireNonAbstractType(Var->getLocation(), Type, 4092 diag::err_abstract_type_in_decl, 4093 AbstractVariableType)) { 4094 Var->setInvalidDecl(); 4095 return; 4096 } 4097 4098 const RecordType *Record 4099 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4100 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4101 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4102 // C++03 [dcl.init]p9: 4103 // If no initializer is specified for an object, and the 4104 // object is of (possibly cv-qualified) non-POD class type (or 4105 // array thereof), the object shall be default-initialized; if 4106 // the object is of const-qualified type, the underlying class 4107 // type shall have a user-declared default 4108 // constructor. Otherwise, if no initializer is specified for 4109 // a non- static object, the object and its subobjects, if 4110 // any, have an indeterminate initial value); if the object 4111 // or any of its subobjects are of const-qualified type, the 4112 // program is ill-formed. 4113 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4114 } else { 4115 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4116 InitializationKind Kind 4117 = InitializationKind::CreateDefault(Var->getLocation()); 4118 4119 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4120 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4121 MultiExprArg(*this, 0, 0)); 4122 if (Init.isInvalid()) 4123 Var->setInvalidDecl(); 4124 else if (Init.get()) 4125 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4126 } 4127 4128 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4129 FinalizeVarWithDestructor(Var, Record); 4130 } 4131} 4132 4133Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4134 DeclPtrTy *Group, 4135 unsigned NumDecls) { 4136 llvm::SmallVector<Decl*, 8> Decls; 4137 4138 if (DS.isTypeSpecOwned()) 4139 Decls.push_back((Decl*)DS.getTypeRep()); 4140 4141 for (unsigned i = 0; i != NumDecls; ++i) 4142 if (Decl *D = Group[i].getAs<Decl>()) 4143 Decls.push_back(D); 4144 4145 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4146 Decls.data(), Decls.size())); 4147} 4148 4149 4150/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4151/// to introduce parameters into function prototype scope. 4152Sema::DeclPtrTy 4153Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4154 const DeclSpec &DS = D.getDeclSpec(); 4155 4156 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4157 VarDecl::StorageClass StorageClass = VarDecl::None; 4158 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4159 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4160 StorageClass = VarDecl::Register; 4161 StorageClassAsWritten = VarDecl::Register; 4162 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4163 Diag(DS.getStorageClassSpecLoc(), 4164 diag::err_invalid_storage_class_in_func_decl); 4165 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4166 } 4167 4168 if (D.getDeclSpec().isThreadSpecified()) 4169 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4170 4171 DiagnoseFunctionSpecifiers(D); 4172 4173 // Check that there are no default arguments inside the type of this 4174 // parameter (C++ only). 4175 if (getLangOptions().CPlusPlus) 4176 CheckExtraCXXDefaultArguments(D); 4177 4178 TypeSourceInfo *TInfo = 0; 4179 TagDecl *OwnedDecl = 0; 4180 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4181 4182 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4183 // C++ [dcl.fct]p6: 4184 // Types shall not be defined in return or parameter types. 4185 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4186 << Context.getTypeDeclType(OwnedDecl); 4187 } 4188 4189 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4190 IdentifierInfo *II = D.getIdentifier(); 4191 if (II) { 4192 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4193 ForRedeclaration); 4194 LookupName(R, S); 4195 if (R.isSingleResult()) { 4196 NamedDecl *PrevDecl = R.getFoundDecl(); 4197 if (PrevDecl->isTemplateParameter()) { 4198 // Maybe we will complain about the shadowed template parameter. 4199 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4200 // Just pretend that we didn't see the previous declaration. 4201 PrevDecl = 0; 4202 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4203 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4204 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4205 4206 // Recover by removing the name 4207 II = 0; 4208 D.SetIdentifier(0, D.getIdentifierLoc()); 4209 D.setInvalidType(true); 4210 } 4211 } 4212 } 4213 4214 // Temporarily put parameter variables in the translation unit, not 4215 // the enclosing context. This prevents them from accidentally 4216 // looking like class members in C++. 4217 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4218 TInfo, parmDeclType, II, 4219 D.getIdentifierLoc(), 4220 StorageClass, StorageClassAsWritten); 4221 4222 if (D.isInvalidType()) 4223 New->setInvalidDecl(); 4224 4225 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4226 if (D.getCXXScopeSpec().isSet()) { 4227 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4228 << D.getCXXScopeSpec().getRange(); 4229 New->setInvalidDecl(); 4230 } 4231 4232 // Add the parameter declaration into this scope. 4233 S->AddDecl(DeclPtrTy::make(New)); 4234 if (II) 4235 IdResolver.AddDecl(New); 4236 4237 ProcessDeclAttributes(S, New, D); 4238 4239 if (New->hasAttr<BlocksAttr>()) { 4240 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4241 } 4242 return DeclPtrTy::make(New); 4243} 4244 4245ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4246 TypeSourceInfo *TSInfo, QualType T, 4247 IdentifierInfo *Name, 4248 SourceLocation NameLoc, 4249 VarDecl::StorageClass StorageClass, 4250 VarDecl::StorageClass StorageClassAsWritten) { 4251 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4252 adjustParameterType(T), TSInfo, 4253 StorageClass, StorageClassAsWritten, 4254 0); 4255 4256 // Parameters can not be abstract class types. 4257 // For record types, this is done by the AbstractClassUsageDiagnoser once 4258 // the class has been completely parsed. 4259 if (!CurContext->isRecord() && 4260 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4261 AbstractParamType)) 4262 New->setInvalidDecl(); 4263 4264 // Parameter declarators cannot be interface types. All ObjC objects are 4265 // passed by reference. 4266 if (T->isObjCInterfaceType()) { 4267 Diag(NameLoc, 4268 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4269 New->setInvalidDecl(); 4270 } 4271 4272 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4273 // duration shall not be qualified by an address-space qualifier." 4274 // Since all parameters have automatic store duration, they can not have 4275 // an address space. 4276 if (T.getAddressSpace() != 0) { 4277 Diag(NameLoc, diag::err_arg_with_address_space); 4278 New->setInvalidDecl(); 4279 } 4280 4281 return New; 4282} 4283 4284void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4285 SourceLocation LocAfterDecls) { 4286 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4287 "Not a function declarator!"); 4288 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4289 4290 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4291 // for a K&R function. 4292 if (!FTI.hasPrototype) { 4293 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4294 --i; 4295 if (FTI.ArgInfo[i].Param == 0) { 4296 llvm::SmallString<256> Code; 4297 llvm::raw_svector_ostream(Code) << " int " 4298 << FTI.ArgInfo[i].Ident->getName() 4299 << ";\n"; 4300 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4301 << FTI.ArgInfo[i].Ident 4302 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4303 4304 // Implicitly declare the argument as type 'int' for lack of a better 4305 // type. 4306 DeclSpec DS; 4307 const char* PrevSpec; // unused 4308 unsigned DiagID; // unused 4309 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4310 PrevSpec, DiagID); 4311 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4312 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4313 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4314 } 4315 } 4316 } 4317} 4318 4319Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4320 Declarator &D) { 4321 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4322 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4323 "Not a function declarator!"); 4324 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4325 4326 if (FTI.hasPrototype) { 4327 // FIXME: Diagnose arguments without names in C. 4328 } 4329 4330 Scope *ParentScope = FnBodyScope->getParent(); 4331 4332 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4333 MultiTemplateParamsArg(*this), 4334 /*IsFunctionDefinition=*/true); 4335 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4336} 4337 4338static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4339 // Don't warn about invalid declarations. 4340 if (FD->isInvalidDecl()) 4341 return false; 4342 4343 // Or declarations that aren't global. 4344 if (!FD->isGlobal()) 4345 return false; 4346 4347 // Don't warn about C++ member functions. 4348 if (isa<CXXMethodDecl>(FD)) 4349 return false; 4350 4351 // Don't warn about 'main'. 4352 if (FD->isMain()) 4353 return false; 4354 4355 // Don't warn about inline functions. 4356 if (FD->isInlineSpecified()) 4357 return false; 4358 4359 // Don't warn about function templates. 4360 if (FD->getDescribedFunctionTemplate()) 4361 return false; 4362 4363 // Don't warn about function template specializations. 4364 if (FD->isFunctionTemplateSpecialization()) 4365 return false; 4366 4367 bool MissingPrototype = true; 4368 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4369 Prev; Prev = Prev->getPreviousDeclaration()) { 4370 // Ignore any declarations that occur in function or method 4371 // scope, because they aren't visible from the header. 4372 if (Prev->getDeclContext()->isFunctionOrMethod()) 4373 continue; 4374 4375 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4376 break; 4377 } 4378 4379 return MissingPrototype; 4380} 4381 4382Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4383 // Clear the last template instantiation error context. 4384 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4385 4386 if (!D) 4387 return D; 4388 FunctionDecl *FD = 0; 4389 4390 if (FunctionTemplateDecl *FunTmpl 4391 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4392 FD = FunTmpl->getTemplatedDecl(); 4393 else 4394 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4395 4396 // Enter a new function scope 4397 PushFunctionScope(); 4398 4399 // See if this is a redefinition. 4400 // But don't complain if we're in GNU89 mode and the previous definition 4401 // was an extern inline function. 4402 const FunctionDecl *Definition; 4403 if (FD->getBody(Definition) && 4404 !canRedefineFunction(Definition, getLangOptions())) { 4405 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4406 Diag(Definition->getLocation(), diag::note_previous_definition); 4407 } 4408 4409 // Builtin functions cannot be defined. 4410 if (unsigned BuiltinID = FD->getBuiltinID()) { 4411 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4412 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4413 FD->setInvalidDecl(); 4414 } 4415 } 4416 4417 // The return type of a function definition must be complete 4418 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4419 QualType ResultType = FD->getResultType(); 4420 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4421 !FD->isInvalidDecl() && 4422 RequireCompleteType(FD->getLocation(), ResultType, 4423 diag::err_func_def_incomplete_result)) 4424 FD->setInvalidDecl(); 4425 4426 // GNU warning -Wmissing-prototypes: 4427 // Warn if a global function is defined without a previous 4428 // prototype declaration. This warning is issued even if the 4429 // definition itself provides a prototype. The aim is to detect 4430 // global functions that fail to be declared in header files. 4431 if (ShouldWarnAboutMissingPrototype(FD)) 4432 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4433 4434 if (FnBodyScope) 4435 PushDeclContext(FnBodyScope, FD); 4436 4437 // Check the validity of our function parameters 4438 CheckParmsForFunctionDef(FD); 4439 4440 bool ShouldCheckShadow = 4441 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4442 4443 // Introduce our parameters into the function scope 4444 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4445 ParmVarDecl *Param = FD->getParamDecl(p); 4446 Param->setOwningFunction(FD); 4447 4448 // If this has an identifier, add it to the scope stack. 4449 if (Param->getIdentifier() && FnBodyScope) { 4450 if (ShouldCheckShadow) 4451 CheckShadow(FnBodyScope, Param); 4452 4453 PushOnScopeChains(Param, FnBodyScope); 4454 } 4455 } 4456 4457 // Checking attributes of current function definition 4458 // dllimport attribute. 4459 if (FD->getAttr<DLLImportAttr>() && 4460 (!FD->getAttr<DLLExportAttr>())) { 4461 // dllimport attribute cannot be applied to definition. 4462 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4463 Diag(FD->getLocation(), 4464 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4465 << "dllimport"; 4466 FD->setInvalidDecl(); 4467 return DeclPtrTy::make(FD); 4468 } 4469 4470 // Visual C++ appears to not think this is an issue, so only issue 4471 // a warning when Microsoft extensions are disabled. 4472 if (!LangOpts.Microsoft) { 4473 // If a symbol previously declared dllimport is later defined, the 4474 // attribute is ignored in subsequent references, and a warning is 4475 // emitted. 4476 Diag(FD->getLocation(), 4477 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4478 << FD->getNameAsCString() << "dllimport"; 4479 } 4480 } 4481 return DeclPtrTy::make(FD); 4482} 4483 4484Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4485 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4486} 4487 4488Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4489 bool IsInstantiation) { 4490 Decl *dcl = D.getAs<Decl>(); 4491 Stmt *Body = BodyArg.takeAs<Stmt>(); 4492 4493 FunctionDecl *FD = 0; 4494 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4495 if (FunTmpl) 4496 FD = FunTmpl->getTemplatedDecl(); 4497 else 4498 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4499 4500 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4501 4502 if (FD) { 4503 FD->setBody(Body); 4504 if (FD->isMain()) { 4505 // C and C++ allow for main to automagically return 0. 4506 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4507 FD->setHasImplicitReturnZero(true); 4508 WP.disableCheckFallThrough(); 4509 } 4510 4511 if (!FD->isInvalidDecl()) 4512 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4513 4514 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4515 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4516 4517 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4518 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4519 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4520 MD->setBody(Body); 4521 MD->setEndLoc(Body->getLocEnd()); 4522 if (!MD->isInvalidDecl()) 4523 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4524 } else { 4525 Body->Destroy(Context); 4526 return DeclPtrTy(); 4527 } 4528 4529 // Verify and clean out per-function state. 4530 4531 // Check goto/label use. 4532 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4533 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4534 LabelStmt *L = I->second; 4535 4536 // Verify that we have no forward references left. If so, there was a goto 4537 // or address of a label taken, but no definition of it. Label fwd 4538 // definitions are indicated with a null substmt. 4539 if (L->getSubStmt() != 0) 4540 continue; 4541 4542 // Emit error. 4543 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4544 4545 // At this point, we have gotos that use the bogus label. Stitch it into 4546 // the function body so that they aren't leaked and that the AST is well 4547 // formed. 4548 if (Body == 0) { 4549 // The whole function wasn't parsed correctly, just delete this. 4550 L->Destroy(Context); 4551 continue; 4552 } 4553 4554 // Otherwise, the body is valid: we want to stitch the label decl into the 4555 // function somewhere so that it is properly owned and so that the goto 4556 // has a valid target. Do this by creating a new compound stmt with the 4557 // label in it. 4558 4559 // Give the label a sub-statement. 4560 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4561 4562 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4563 cast<CXXTryStmt>(Body)->getTryBlock() : 4564 cast<CompoundStmt>(Body); 4565 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4566 Compound->body_end()); 4567 Elements.push_back(L); 4568 Compound->setStmts(Context, Elements.data(), Elements.size()); 4569 } 4570 4571 if (Body) { 4572 // C++ constructors that have function-try-blocks can't have return 4573 // statements in the handlers of that block. (C++ [except.handle]p14) 4574 // Verify this. 4575 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4576 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4577 4578 // Verify that that gotos and switch cases don't jump into scopes illegally. 4579 // Verify that that gotos and switch cases don't jump into scopes illegally. 4580 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 4581 DiagnoseInvalidJumps(Body); 4582 4583 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4584 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4585 Destructor->getParent()); 4586 4587 // If any errors have occurred, clear out any temporaries that may have 4588 // been leftover. This ensures that these temporaries won't be picked up for 4589 // deletion in some later function. 4590 if (PP.getDiagnostics().hasErrorOccurred()) 4591 ExprTemporaries.clear(); 4592 else if (!isa<FunctionTemplateDecl>(dcl)) { 4593 // Since the body is valid, issue any analysis-based warnings that are 4594 // enabled. 4595 QualType ResultType; 4596 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4597 ResultType = FD->getResultType(); 4598 } 4599 else { 4600 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4601 ResultType = MD->getResultType(); 4602 } 4603 AnalysisWarnings.IssueWarnings(WP, dcl); 4604 } 4605 4606 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4607 } 4608 4609 if (!IsInstantiation) 4610 PopDeclContext(); 4611 4612 PopFunctionOrBlockScope(); 4613 4614 // If any errors have occurred, clear out any temporaries that may have 4615 // been leftover. This ensures that these temporaries won't be picked up for 4616 // deletion in some later function. 4617 if (getDiagnostics().hasErrorOccurred()) 4618 ExprTemporaries.clear(); 4619 4620 return D; 4621} 4622 4623/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4624/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4625NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4626 IdentifierInfo &II, Scope *S) { 4627 // Before we produce a declaration for an implicitly defined 4628 // function, see whether there was a locally-scoped declaration of 4629 // this name as a function or variable. If so, use that 4630 // (non-visible) declaration, and complain about it. 4631 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4632 = LocallyScopedExternalDecls.find(&II); 4633 if (Pos != LocallyScopedExternalDecls.end()) { 4634 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4635 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4636 return Pos->second; 4637 } 4638 4639 // Extension in C99. Legal in C90, but warn about it. 4640 if (II.getName().startswith("__builtin_")) 4641 Diag(Loc, diag::warn_builtin_unknown) << &II; 4642 else if (getLangOptions().C99) 4643 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4644 else 4645 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4646 4647 // Set a Declarator for the implicit definition: int foo(); 4648 const char *Dummy; 4649 DeclSpec DS; 4650 unsigned DiagID; 4651 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4652 Error = Error; // Silence warning. 4653 assert(!Error && "Error setting up implicit decl!"); 4654 Declarator D(DS, Declarator::BlockContext); 4655 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4656 0, 0, false, SourceLocation(), 4657 false, 0,0,0, Loc, Loc, D), 4658 SourceLocation()); 4659 D.SetIdentifier(&II, Loc); 4660 4661 // Insert this function into translation-unit scope. 4662 4663 DeclContext *PrevDC = CurContext; 4664 CurContext = Context.getTranslationUnitDecl(); 4665 4666 FunctionDecl *FD = 4667 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4668 FD->setImplicit(); 4669 4670 CurContext = PrevDC; 4671 4672 AddKnownFunctionAttributes(FD); 4673 4674 return FD; 4675} 4676 4677/// \brief Adds any function attributes that we know a priori based on 4678/// the declaration of this function. 4679/// 4680/// These attributes can apply both to implicitly-declared builtins 4681/// (like __builtin___printf_chk) or to library-declared functions 4682/// like NSLog or printf. 4683void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4684 if (FD->isInvalidDecl()) 4685 return; 4686 4687 // If this is a built-in function, map its builtin attributes to 4688 // actual attributes. 4689 if (unsigned BuiltinID = FD->getBuiltinID()) { 4690 // Handle printf-formatting attributes. 4691 unsigned FormatIdx; 4692 bool HasVAListArg; 4693 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4694 if (!FD->getAttr<FormatAttr>()) 4695 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4696 HasVAListArg ? 0 : FormatIdx+2)); 4697 } 4698 4699 // Mark const if we don't care about errno and that is the only 4700 // thing preventing the function from being const. This allows 4701 // IRgen to use LLVM intrinsics for such functions. 4702 if (!getLangOptions().MathErrno && 4703 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4704 if (!FD->getAttr<ConstAttr>()) 4705 FD->addAttr(::new (Context) ConstAttr()); 4706 } 4707 4708 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4709 FD->setType(Context.getNoReturnType(FD->getType())); 4710 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4711 FD->addAttr(::new (Context) NoThrowAttr()); 4712 if (Context.BuiltinInfo.isConst(BuiltinID)) 4713 FD->addAttr(::new (Context) ConstAttr()); 4714 } 4715 4716 IdentifierInfo *Name = FD->getIdentifier(); 4717 if (!Name) 4718 return; 4719 if ((!getLangOptions().CPlusPlus && 4720 FD->getDeclContext()->isTranslationUnit()) || 4721 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4722 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4723 LinkageSpecDecl::lang_c)) { 4724 // Okay: this could be a libc/libm/Objective-C function we know 4725 // about. 4726 } else 4727 return; 4728 4729 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4730 // FIXME: NSLog and NSLogv should be target specific 4731 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4732 // FIXME: We known better than our headers. 4733 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4734 } else 4735 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4736 Name->isStr("NSLogv") ? 0 : 2)); 4737 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4738 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4739 // target-specific builtins, perhaps? 4740 if (!FD->getAttr<FormatAttr>()) 4741 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4742 Name->isStr("vasprintf") ? 0 : 3)); 4743 } 4744} 4745 4746TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4747 TypeSourceInfo *TInfo) { 4748 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4749 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4750 4751 if (!TInfo) { 4752 assert(D.isInvalidType() && "no declarator info for valid type"); 4753 TInfo = Context.getTrivialTypeSourceInfo(T); 4754 } 4755 4756 // Scope manipulation handled by caller. 4757 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4758 D.getIdentifierLoc(), 4759 D.getIdentifier(), 4760 TInfo); 4761 4762 if (const TagType *TT = T->getAs<TagType>()) { 4763 TagDecl *TD = TT->getDecl(); 4764 4765 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4766 // keep track of the TypedefDecl. 4767 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4768 TD->setTypedefForAnonDecl(NewTD); 4769 } 4770 4771 if (D.isInvalidType()) 4772 NewTD->setInvalidDecl(); 4773 return NewTD; 4774} 4775 4776 4777/// \brief Determine whether a tag with a given kind is acceptable 4778/// as a redeclaration of the given tag declaration. 4779/// 4780/// \returns true if the new tag kind is acceptable, false otherwise. 4781bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4782 TagDecl::TagKind NewTag, 4783 SourceLocation NewTagLoc, 4784 const IdentifierInfo &Name) { 4785 // C++ [dcl.type.elab]p3: 4786 // The class-key or enum keyword present in the 4787 // elaborated-type-specifier shall agree in kind with the 4788 // declaration to which the name in theelaborated-type-specifier 4789 // refers. This rule also applies to the form of 4790 // elaborated-type-specifier that declares a class-name or 4791 // friend class since it can be construed as referring to the 4792 // definition of the class. Thus, in any 4793 // elaborated-type-specifier, the enum keyword shall be used to 4794 // refer to an enumeration (7.2), the union class-keyshall be 4795 // used to refer to a union (clause 9), and either the class or 4796 // struct class-key shall be used to refer to a class (clause 9) 4797 // declared using the class or struct class-key. 4798 TagDecl::TagKind OldTag = Previous->getTagKind(); 4799 if (OldTag == NewTag) 4800 return true; 4801 4802 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4803 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4804 // Warn about the struct/class tag mismatch. 4805 bool isTemplate = false; 4806 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4807 isTemplate = Record->getDescribedClassTemplate(); 4808 4809 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4810 << (NewTag == TagDecl::TK_class) 4811 << isTemplate << &Name 4812 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 4813 OldTag == TagDecl::TK_class? "class" : "struct"); 4814 Diag(Previous->getLocation(), diag::note_previous_use); 4815 return true; 4816 } 4817 return false; 4818} 4819 4820/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4821/// former case, Name will be non-null. In the later case, Name will be null. 4822/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4823/// reference/declaration/definition of a tag. 4824Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4825 SourceLocation KWLoc, CXXScopeSpec &SS, 4826 IdentifierInfo *Name, SourceLocation NameLoc, 4827 AttributeList *Attr, AccessSpecifier AS, 4828 MultiTemplateParamsArg TemplateParameterLists, 4829 bool &OwnedDecl, bool &IsDependent) { 4830 // If this is not a definition, it must have a name. 4831 assert((Name != 0 || TUK == TUK_Definition) && 4832 "Nameless record must be a definition!"); 4833 4834 OwnedDecl = false; 4835 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4836 4837 // FIXME: Check explicit specializations more carefully. 4838 bool isExplicitSpecialization = false; 4839 if (TUK != TUK_Reference) { 4840 if (TemplateParameterList *TemplateParams 4841 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4842 (TemplateParameterList**)TemplateParameterLists.get(), 4843 TemplateParameterLists.size(), 4844 TUK == TUK_Friend, 4845 isExplicitSpecialization)) { 4846 if (TemplateParams->size() > 0) { 4847 // This is a declaration or definition of a class template (which may 4848 // be a member of another template). 4849 OwnedDecl = false; 4850 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4851 SS, Name, NameLoc, Attr, 4852 TemplateParams, 4853 AS); 4854 TemplateParameterLists.release(); 4855 return Result.get(); 4856 } else { 4857 // The "template<>" header is extraneous. 4858 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4859 << ElaboratedType::getNameForTagKind(Kind) << Name; 4860 isExplicitSpecialization = true; 4861 } 4862 } 4863 4864 TemplateParameterLists.release(); 4865 } 4866 4867 DeclContext *SearchDC = CurContext; 4868 DeclContext *DC = CurContext; 4869 bool isStdBadAlloc = false; 4870 bool Invalid = false; 4871 4872 RedeclarationKind Redecl = ForRedeclaration; 4873 if (TUK == TUK_Friend || TUK == TUK_Reference) 4874 Redecl = NotForRedeclaration; 4875 4876 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4877 4878 if (Name && SS.isNotEmpty()) { 4879 // We have a nested-name tag ('struct foo::bar'). 4880 4881 // Check for invalid 'foo::'. 4882 if (SS.isInvalid()) { 4883 Name = 0; 4884 goto CreateNewDecl; 4885 } 4886 4887 // If this is a friend or a reference to a class in a dependent 4888 // context, don't try to make a decl for it. 4889 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4890 DC = computeDeclContext(SS, false); 4891 if (!DC) { 4892 IsDependent = true; 4893 return DeclPtrTy(); 4894 } 4895 } 4896 4897 if (RequireCompleteDeclContext(SS)) 4898 return DeclPtrTy::make((Decl *)0); 4899 4900 DC = computeDeclContext(SS, true); 4901 SearchDC = DC; 4902 // Look-up name inside 'foo::'. 4903 LookupQualifiedName(Previous, DC); 4904 4905 if (Previous.isAmbiguous()) 4906 return DeclPtrTy(); 4907 4908 if (Previous.empty()) { 4909 // Name lookup did not find anything. However, if the 4910 // nested-name-specifier refers to the current instantiation, 4911 // and that current instantiation has any dependent base 4912 // classes, we might find something at instantiation time: treat 4913 // this as a dependent elaborated-type-specifier. 4914 if (Previous.wasNotFoundInCurrentInstantiation()) { 4915 IsDependent = true; 4916 return DeclPtrTy(); 4917 } 4918 4919 // A tag 'foo::bar' must already exist. 4920 Diag(NameLoc, diag::err_not_tag_in_scope) 4921 << Kind << Name << DC << SS.getRange(); 4922 Name = 0; 4923 Invalid = true; 4924 goto CreateNewDecl; 4925 } 4926 } else if (Name) { 4927 // If this is a named struct, check to see if there was a previous forward 4928 // declaration or definition. 4929 // FIXME: We're looking into outer scopes here, even when we 4930 // shouldn't be. Doing so can result in ambiguities that we 4931 // shouldn't be diagnosing. 4932 LookupName(Previous, S); 4933 4934 // Note: there used to be some attempt at recovery here. 4935 if (Previous.isAmbiguous()) 4936 return DeclPtrTy(); 4937 4938 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4939 // FIXME: This makes sure that we ignore the contexts associated 4940 // with C structs, unions, and enums when looking for a matching 4941 // tag declaration or definition. See the similar lookup tweak 4942 // in Sema::LookupName; is there a better way to deal with this? 4943 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4944 SearchDC = SearchDC->getParent(); 4945 } 4946 } 4947 4948 if (Previous.isSingleResult() && 4949 Previous.getFoundDecl()->isTemplateParameter()) { 4950 // Maybe we will complain about the shadowed template parameter. 4951 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4952 // Just pretend that we didn't see the previous declaration. 4953 Previous.clear(); 4954 } 4955 4956 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4957 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4958 // This is a declaration of or a reference to "std::bad_alloc". 4959 isStdBadAlloc = true; 4960 4961 if (Previous.empty() && StdBadAlloc) { 4962 // std::bad_alloc has been implicitly declared (but made invisible to 4963 // name lookup). Fill in this implicit declaration as the previous 4964 // declaration, so that the declarations get chained appropriately. 4965 Previous.addDecl(StdBadAlloc); 4966 } 4967 } 4968 4969 // If we didn't find a previous declaration, and this is a reference 4970 // (or friend reference), move to the correct scope. In C++, we 4971 // also need to do a redeclaration lookup there, just in case 4972 // there's a shadow friend decl. 4973 if (Name && Previous.empty() && 4974 (TUK == TUK_Reference || TUK == TUK_Friend)) { 4975 if (Invalid) goto CreateNewDecl; 4976 assert(SS.isEmpty()); 4977 4978 if (TUK == TUK_Reference) { 4979 // C++ [basic.scope.pdecl]p5: 4980 // -- for an elaborated-type-specifier of the form 4981 // 4982 // class-key identifier 4983 // 4984 // if the elaborated-type-specifier is used in the 4985 // decl-specifier-seq or parameter-declaration-clause of a 4986 // function defined in namespace scope, the identifier is 4987 // declared as a class-name in the namespace that contains 4988 // the declaration; otherwise, except as a friend 4989 // declaration, the identifier is declared in the smallest 4990 // non-class, non-function-prototype scope that contains the 4991 // declaration. 4992 // 4993 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4994 // C structs and unions. 4995 // 4996 // It is an error in C++ to declare (rather than define) an enum 4997 // type, including via an elaborated type specifier. We'll 4998 // diagnose that later; for now, declare the enum in the same 4999 // scope as we would have picked for any other tag type. 5000 // 5001 // GNU C also supports this behavior as part of its incomplete 5002 // enum types extension, while GNU C++ does not. 5003 // 5004 // Find the context where we'll be declaring the tag. 5005 // FIXME: We would like to maintain the current DeclContext as the 5006 // lexical context, 5007 while (SearchDC->isRecord()) 5008 SearchDC = SearchDC->getParent(); 5009 5010 // Find the scope where we'll be declaring the tag. 5011 while (S->isClassScope() || 5012 (getLangOptions().CPlusPlus && 5013 S->isFunctionPrototypeScope()) || 5014 ((S->getFlags() & Scope::DeclScope) == 0) || 5015 (S->getEntity() && 5016 ((DeclContext *)S->getEntity())->isTransparentContext())) 5017 S = S->getParent(); 5018 } else { 5019 assert(TUK == TUK_Friend); 5020 // C++ [namespace.memdef]p3: 5021 // If a friend declaration in a non-local class first declares a 5022 // class or function, the friend class or function is a member of 5023 // the innermost enclosing namespace. 5024 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5025 } 5026 5027 // In C++, we need to do a redeclaration lookup to properly 5028 // diagnose some problems. 5029 if (getLangOptions().CPlusPlus) { 5030 Previous.setRedeclarationKind(ForRedeclaration); 5031 LookupQualifiedName(Previous, SearchDC); 5032 } 5033 } 5034 5035 if (!Previous.empty()) { 5036 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5037 5038 // It's okay to have a tag decl in the same scope as a typedef 5039 // which hides a tag decl in the same scope. Finding this 5040 // insanity with a redeclaration lookup can only actually happen 5041 // in C++. 5042 // 5043 // This is also okay for elaborated-type-specifiers, which is 5044 // technically forbidden by the current standard but which is 5045 // okay according to the likely resolution of an open issue; 5046 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5047 if (getLangOptions().CPlusPlus) { 5048 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5049 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5050 TagDecl *Tag = TT->getDecl(); 5051 if (Tag->getDeclName() == Name && 5052 Tag->getDeclContext()->getLookupContext() 5053 ->Equals(TD->getDeclContext()->getLookupContext())) { 5054 PrevDecl = Tag; 5055 Previous.clear(); 5056 Previous.addDecl(Tag); 5057 } 5058 } 5059 } 5060 } 5061 5062 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5063 // If this is a use of a previous tag, or if the tag is already declared 5064 // in the same scope (so that the definition/declaration completes or 5065 // rementions the tag), reuse the decl. 5066 if (TUK == TUK_Reference || TUK == TUK_Friend || 5067 isDeclInScope(PrevDecl, SearchDC, S)) { 5068 // Make sure that this wasn't declared as an enum and now used as a 5069 // struct or something similar. 5070 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5071 bool SafeToContinue 5072 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 5073 Kind != TagDecl::TK_enum); 5074 if (SafeToContinue) 5075 Diag(KWLoc, diag::err_use_with_wrong_tag) 5076 << Name 5077 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5078 PrevTagDecl->getKindName()); 5079 else 5080 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5081 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5082 5083 if (SafeToContinue) 5084 Kind = PrevTagDecl->getTagKind(); 5085 else { 5086 // Recover by making this an anonymous redefinition. 5087 Name = 0; 5088 Previous.clear(); 5089 Invalid = true; 5090 } 5091 } 5092 5093 if (!Invalid) { 5094 // If this is a use, just return the declaration we found. 5095 5096 // FIXME: In the future, return a variant or some other clue 5097 // for the consumer of this Decl to know it doesn't own it. 5098 // For our current ASTs this shouldn't be a problem, but will 5099 // need to be changed with DeclGroups. 5100 if (TUK == TUK_Reference || TUK == TUK_Friend) 5101 return DeclPtrTy::make(PrevTagDecl); 5102 5103 // Diagnose attempts to redefine a tag. 5104 if (TUK == TUK_Definition) { 5105 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5106 // If we're defining a specialization and the previous definition 5107 // is from an implicit instantiation, don't emit an error 5108 // here; we'll catch this in the general case below. 5109 if (!isExplicitSpecialization || 5110 !isa<CXXRecordDecl>(Def) || 5111 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5112 == TSK_ExplicitSpecialization) { 5113 Diag(NameLoc, diag::err_redefinition) << Name; 5114 Diag(Def->getLocation(), diag::note_previous_definition); 5115 // If this is a redefinition, recover by making this 5116 // struct be anonymous, which will make any later 5117 // references get the previous definition. 5118 Name = 0; 5119 Previous.clear(); 5120 Invalid = true; 5121 } 5122 } else { 5123 // If the type is currently being defined, complain 5124 // about a nested redefinition. 5125 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5126 if (Tag->isBeingDefined()) { 5127 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5128 Diag(PrevTagDecl->getLocation(), 5129 diag::note_previous_definition); 5130 Name = 0; 5131 Previous.clear(); 5132 Invalid = true; 5133 } 5134 } 5135 5136 // Okay, this is definition of a previously declared or referenced 5137 // tag PrevDecl. We're going to create a new Decl for it. 5138 } 5139 } 5140 // If we get here we have (another) forward declaration or we 5141 // have a definition. Just create a new decl. 5142 5143 } else { 5144 // If we get here, this is a definition of a new tag type in a nested 5145 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5146 // new decl/type. We set PrevDecl to NULL so that the entities 5147 // have distinct types. 5148 Previous.clear(); 5149 } 5150 // If we get here, we're going to create a new Decl. If PrevDecl 5151 // is non-NULL, it's a definition of the tag declared by 5152 // PrevDecl. If it's NULL, we have a new definition. 5153 5154 5155 // Otherwise, PrevDecl is not a tag, but was found with tag 5156 // lookup. This is only actually possible in C++, where a few 5157 // things like templates still live in the tag namespace. 5158 } else { 5159 assert(getLangOptions().CPlusPlus); 5160 5161 // Use a better diagnostic if an elaborated-type-specifier 5162 // found the wrong kind of type on the first 5163 // (non-redeclaration) lookup. 5164 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5165 !Previous.isForRedeclaration()) { 5166 unsigned Kind = 0; 5167 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5168 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5169 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5170 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5171 Invalid = true; 5172 5173 // Otherwise, only diagnose if the declaration is in scope. 5174 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5175 // do nothing 5176 5177 // Diagnose implicit declarations introduced by elaborated types. 5178 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5179 unsigned Kind = 0; 5180 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5181 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5182 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5183 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5184 Invalid = true; 5185 5186 // Otherwise it's a declaration. Call out a particularly common 5187 // case here. 5188 } else if (isa<TypedefDecl>(PrevDecl)) { 5189 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5190 << Name 5191 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5192 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5193 Invalid = true; 5194 5195 // Otherwise, diagnose. 5196 } else { 5197 // The tag name clashes with something else in the target scope, 5198 // issue an error and recover by making this tag be anonymous. 5199 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5200 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5201 Name = 0; 5202 Invalid = true; 5203 } 5204 5205 // The existing declaration isn't relevant to us; we're in a 5206 // new scope, so clear out the previous declaration. 5207 Previous.clear(); 5208 } 5209 } 5210 5211CreateNewDecl: 5212 5213 TagDecl *PrevDecl = 0; 5214 if (Previous.isSingleResult()) 5215 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5216 5217 // If there is an identifier, use the location of the identifier as the 5218 // location of the decl, otherwise use the location of the struct/union 5219 // keyword. 5220 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5221 5222 // Otherwise, create a new declaration. If there is a previous 5223 // declaration of the same entity, the two will be linked via 5224 // PrevDecl. 5225 TagDecl *New; 5226 5227 if (Kind == TagDecl::TK_enum) { 5228 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5229 // enum X { A, B, C } D; D should chain to X. 5230 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5231 cast_or_null<EnumDecl>(PrevDecl)); 5232 // If this is an undefined enum, warn. 5233 if (TUK != TUK_Definition && !Invalid) { 5234 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5235 : diag::ext_forward_ref_enum; 5236 Diag(Loc, DK); 5237 } 5238 } else { 5239 // struct/union/class 5240 5241 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5242 // struct X { int A; } D; D should chain to X. 5243 if (getLangOptions().CPlusPlus) { 5244 // FIXME: Look for a way to use RecordDecl for simple structs. 5245 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5246 cast_or_null<CXXRecordDecl>(PrevDecl)); 5247 5248 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5249 StdBadAlloc = cast<CXXRecordDecl>(New); 5250 } else 5251 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5252 cast_or_null<RecordDecl>(PrevDecl)); 5253 } 5254 5255 // Maybe add qualifier info. 5256 if (SS.isNotEmpty()) { 5257 NestedNameSpecifier *NNS 5258 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5259 New->setQualifierInfo(NNS, SS.getRange()); 5260 } 5261 5262 if (Kind != TagDecl::TK_enum) { 5263 // Handle #pragma pack: if the #pragma pack stack has non-default 5264 // alignment, make up a packed attribute for this decl. These 5265 // attributes are checked when the ASTContext lays out the 5266 // structure. 5267 // 5268 // It is important for implementing the correct semantics that this 5269 // happen here (in act on tag decl). The #pragma pack stack is 5270 // maintained as a result of parser callbacks which can occur at 5271 // many points during the parsing of a struct declaration (because 5272 // the #pragma tokens are effectively skipped over during the 5273 // parsing of the struct). 5274 if (unsigned Alignment = getPragmaPackAlignment()) 5275 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5276 } 5277 5278 // If this is a specialization of a member class (of a class template), 5279 // check the specialization. 5280 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5281 Invalid = true; 5282 5283 if (Invalid) 5284 New->setInvalidDecl(); 5285 5286 if (Attr) 5287 ProcessDeclAttributeList(S, New, Attr); 5288 5289 // If we're declaring or defining a tag in function prototype scope 5290 // in C, note that this type can only be used within the function. 5291 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5292 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5293 5294 // Set the lexical context. If the tag has a C++ scope specifier, the 5295 // lexical context will be different from the semantic context. 5296 New->setLexicalDeclContext(CurContext); 5297 5298 // Mark this as a friend decl if applicable. 5299 if (TUK == TUK_Friend) 5300 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5301 5302 // Set the access specifier. 5303 if (!Invalid && SearchDC->isRecord()) 5304 SetMemberAccessSpecifier(New, PrevDecl, AS); 5305 5306 if (TUK == TUK_Definition) 5307 New->startDefinition(); 5308 5309 // If this has an identifier, add it to the scope stack. 5310 if (TUK == TUK_Friend) { 5311 // We might be replacing an existing declaration in the lookup tables; 5312 // if so, borrow its access specifier. 5313 if (PrevDecl) 5314 New->setAccess(PrevDecl->getAccess()); 5315 5316 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5317 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5318 if (Name) // can be null along some error paths 5319 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5320 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5321 } else if (Name) { 5322 S = getNonFieldDeclScope(S); 5323 PushOnScopeChains(New, S); 5324 } else { 5325 CurContext->addDecl(New); 5326 } 5327 5328 // If this is the C FILE type, notify the AST context. 5329 if (IdentifierInfo *II = New->getIdentifier()) 5330 if (!New->isInvalidDecl() && 5331 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5332 II->isStr("FILE")) 5333 Context.setFILEDecl(New); 5334 5335 OwnedDecl = true; 5336 return DeclPtrTy::make(New); 5337} 5338 5339void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5340 AdjustDeclIfTemplate(TagD); 5341 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5342 5343 // Enter the tag context. 5344 PushDeclContext(S, Tag); 5345} 5346 5347void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5348 SourceLocation LBraceLoc) { 5349 AdjustDeclIfTemplate(TagD); 5350 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5351 5352 FieldCollector->StartClass(); 5353 5354 if (!Record->getIdentifier()) 5355 return; 5356 5357 // C++ [class]p2: 5358 // [...] The class-name is also inserted into the scope of the 5359 // class itself; this is known as the injected-class-name. For 5360 // purposes of access checking, the injected-class-name is treated 5361 // as if it were a public member name. 5362 CXXRecordDecl *InjectedClassName 5363 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5364 CurContext, Record->getLocation(), 5365 Record->getIdentifier(), 5366 Record->getTagKeywordLoc(), 5367 Record); 5368 InjectedClassName->setImplicit(); 5369 InjectedClassName->setAccess(AS_public); 5370 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5371 InjectedClassName->setDescribedClassTemplate(Template); 5372 PushOnScopeChains(InjectedClassName, S); 5373 assert(InjectedClassName->isInjectedClassName() && 5374 "Broken injected-class-name"); 5375} 5376 5377// Traverses the class and any nested classes, making a note of any 5378// dynamic classes that have no key function so that we can mark all of 5379// their virtual member functions as "used" at the end of the translation 5380// unit. This ensures that all functions needed by the vtable will get 5381// instantiated/synthesized. 5382static void 5383RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5384 SourceLocation Loc) { 5385 // We don't look at dependent or undefined classes. 5386 if (Record->isDependentContext() || !Record->isDefinition()) 5387 return; 5388 5389 if (Record->isDynamicClass()) { 5390 const CXXMethodDecl *KeyFunction = S.Context.getKeyFunction(Record); 5391 5392 if (!KeyFunction) 5393 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, 5394 Loc)); 5395 5396 if ((!KeyFunction || (KeyFunction->getBody() && KeyFunction->isInlined())) 5397 && Record->getLinkage() == ExternalLinkage) 5398 S.Diag(Record->getLocation(), diag::warn_weak_vtable) << Record; 5399 } 5400 for (DeclContext::decl_iterator D = Record->decls_begin(), 5401 DEnd = Record->decls_end(); 5402 D != DEnd; ++D) { 5403 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5404 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5405 } 5406} 5407 5408void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5409 SourceLocation RBraceLoc) { 5410 AdjustDeclIfTemplate(TagD); 5411 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5412 Tag->setRBraceLoc(RBraceLoc); 5413 5414 if (isa<CXXRecordDecl>(Tag)) 5415 FieldCollector->FinishClass(); 5416 5417 // Exit this scope of this tag's definition. 5418 PopDeclContext(); 5419 5420 if (isa<CXXRecordDecl>(Tag) && !Tag->getLexicalDeclContext()->isRecord()) 5421 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5422 RBraceLoc); 5423 5424 // Notify the consumer that we've defined a tag. 5425 Consumer.HandleTagDeclDefinition(Tag); 5426} 5427 5428void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5429 AdjustDeclIfTemplate(TagD); 5430 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5431 Tag->setInvalidDecl(); 5432 5433 // We're undoing ActOnTagStartDefinition here, not 5434 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5435 // the FieldCollector. 5436 5437 PopDeclContext(); 5438} 5439 5440// Note that FieldName may be null for anonymous bitfields. 5441bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5442 QualType FieldTy, const Expr *BitWidth, 5443 bool *ZeroWidth) { 5444 // Default to true; that shouldn't confuse checks for emptiness 5445 if (ZeroWidth) 5446 *ZeroWidth = true; 5447 5448 // C99 6.7.2.1p4 - verify the field type. 5449 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5450 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5451 // Handle incomplete types with specific error. 5452 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5453 return true; 5454 if (FieldName) 5455 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5456 << FieldName << FieldTy << BitWidth->getSourceRange(); 5457 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5458 << FieldTy << BitWidth->getSourceRange(); 5459 } 5460 5461 // If the bit-width is type- or value-dependent, don't try to check 5462 // it now. 5463 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5464 return false; 5465 5466 llvm::APSInt Value; 5467 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5468 return true; 5469 5470 if (Value != 0 && ZeroWidth) 5471 *ZeroWidth = false; 5472 5473 // Zero-width bitfield is ok for anonymous field. 5474 if (Value == 0 && FieldName) 5475 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5476 5477 if (Value.isSigned() && Value.isNegative()) { 5478 if (FieldName) 5479 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5480 << FieldName << Value.toString(10); 5481 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5482 << Value.toString(10); 5483 } 5484 5485 if (!FieldTy->isDependentType()) { 5486 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5487 if (Value.getZExtValue() > TypeSize) { 5488 if (!getLangOptions().CPlusPlus) { 5489 if (FieldName) 5490 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5491 << FieldName << (unsigned)Value.getZExtValue() 5492 << (unsigned)TypeSize; 5493 5494 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5495 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5496 } 5497 5498 if (FieldName) 5499 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5500 << FieldName << (unsigned)Value.getZExtValue() 5501 << (unsigned)TypeSize; 5502 else 5503 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5504 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5505 } 5506 } 5507 5508 return false; 5509} 5510 5511/// ActOnField - Each field of a struct/union/class is passed into this in order 5512/// to create a FieldDecl object for it. 5513Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5514 SourceLocation DeclStart, 5515 Declarator &D, ExprTy *BitfieldWidth) { 5516 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5517 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5518 AS_public); 5519 return DeclPtrTy::make(Res); 5520} 5521 5522/// HandleField - Analyze a field of a C struct or a C++ data member. 5523/// 5524FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5525 SourceLocation DeclStart, 5526 Declarator &D, Expr *BitWidth, 5527 AccessSpecifier AS) { 5528 IdentifierInfo *II = D.getIdentifier(); 5529 SourceLocation Loc = DeclStart; 5530 if (II) Loc = D.getIdentifierLoc(); 5531 5532 TypeSourceInfo *TInfo = 0; 5533 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5534 if (getLangOptions().CPlusPlus) 5535 CheckExtraCXXDefaultArguments(D); 5536 5537 DiagnoseFunctionSpecifiers(D); 5538 5539 if (D.getDeclSpec().isThreadSpecified()) 5540 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5541 5542 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5543 ForRedeclaration); 5544 5545 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5546 // Maybe we will complain about the shadowed template parameter. 5547 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5548 // Just pretend that we didn't see the previous declaration. 5549 PrevDecl = 0; 5550 } 5551 5552 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5553 PrevDecl = 0; 5554 5555 bool Mutable 5556 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5557 SourceLocation TSSL = D.getSourceRange().getBegin(); 5558 FieldDecl *NewFD 5559 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5560 AS, PrevDecl, &D); 5561 5562 if (NewFD->isInvalidDecl()) 5563 Record->setInvalidDecl(); 5564 5565 if (NewFD->isInvalidDecl() && PrevDecl) { 5566 // Don't introduce NewFD into scope; there's already something 5567 // with the same name in the same scope. 5568 } else if (II) { 5569 PushOnScopeChains(NewFD, S); 5570 } else 5571 Record->addDecl(NewFD); 5572 5573 return NewFD; 5574} 5575 5576/// \brief Build a new FieldDecl and check its well-formedness. 5577/// 5578/// This routine builds a new FieldDecl given the fields name, type, 5579/// record, etc. \p PrevDecl should refer to any previous declaration 5580/// with the same name and in the same scope as the field to be 5581/// created. 5582/// 5583/// \returns a new FieldDecl. 5584/// 5585/// \todo The Declarator argument is a hack. It will be removed once 5586FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5587 TypeSourceInfo *TInfo, 5588 RecordDecl *Record, SourceLocation Loc, 5589 bool Mutable, Expr *BitWidth, 5590 SourceLocation TSSL, 5591 AccessSpecifier AS, NamedDecl *PrevDecl, 5592 Declarator *D) { 5593 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5594 bool InvalidDecl = false; 5595 if (D) InvalidDecl = D->isInvalidType(); 5596 5597 // If we receive a broken type, recover by assuming 'int' and 5598 // marking this declaration as invalid. 5599 if (T.isNull()) { 5600 InvalidDecl = true; 5601 T = Context.IntTy; 5602 } 5603 5604 QualType EltTy = Context.getBaseElementType(T); 5605 if (!EltTy->isDependentType() && 5606 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5607 InvalidDecl = true; 5608 5609 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5610 // than a variably modified type. 5611 if (!InvalidDecl && T->isVariablyModifiedType()) { 5612 bool SizeIsNegative; 5613 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5614 SizeIsNegative); 5615 if (!FixedTy.isNull()) { 5616 Diag(Loc, diag::warn_illegal_constant_array_size); 5617 T = FixedTy; 5618 } else { 5619 if (SizeIsNegative) 5620 Diag(Loc, diag::err_typecheck_negative_array_size); 5621 else 5622 Diag(Loc, diag::err_typecheck_field_variable_size); 5623 InvalidDecl = true; 5624 } 5625 } 5626 5627 // Fields can not have abstract class types 5628 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5629 diag::err_abstract_type_in_decl, 5630 AbstractFieldType)) 5631 InvalidDecl = true; 5632 5633 bool ZeroWidth = false; 5634 // If this is declared as a bit-field, check the bit-field. 5635 if (!InvalidDecl && BitWidth && 5636 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5637 InvalidDecl = true; 5638 DeleteExpr(BitWidth); 5639 BitWidth = 0; 5640 ZeroWidth = false; 5641 } 5642 5643 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5644 BitWidth, Mutable); 5645 if (InvalidDecl) 5646 NewFD->setInvalidDecl(); 5647 5648 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5649 Diag(Loc, diag::err_duplicate_member) << II; 5650 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5651 NewFD->setInvalidDecl(); 5652 } 5653 5654 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5655 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5656 5657 if (!T->isPODType()) 5658 CXXRecord->setPOD(false); 5659 if (!ZeroWidth) 5660 CXXRecord->setEmpty(false); 5661 5662 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5663 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5664 5665 if (!RDecl->hasTrivialConstructor()) 5666 CXXRecord->setHasTrivialConstructor(false); 5667 if (!RDecl->hasTrivialCopyConstructor()) 5668 CXXRecord->setHasTrivialCopyConstructor(false); 5669 if (!RDecl->hasTrivialCopyAssignment()) 5670 CXXRecord->setHasTrivialCopyAssignment(false); 5671 if (!RDecl->hasTrivialDestructor()) 5672 CXXRecord->setHasTrivialDestructor(false); 5673 5674 // C++ 9.5p1: An object of a class with a non-trivial 5675 // constructor, a non-trivial copy constructor, a non-trivial 5676 // destructor, or a non-trivial copy assignment operator 5677 // cannot be a member of a union, nor can an array of such 5678 // objects. 5679 // TODO: C++0x alters this restriction significantly. 5680 if (Record->isUnion()) { 5681 // We check for copy constructors before constructors 5682 // because otherwise we'll never get complaints about 5683 // copy constructors. 5684 5685 CXXSpecialMember member = CXXInvalid; 5686 if (!RDecl->hasTrivialCopyConstructor()) 5687 member = CXXCopyConstructor; 5688 else if (!RDecl->hasTrivialConstructor()) 5689 member = CXXConstructor; 5690 else if (!RDecl->hasTrivialCopyAssignment()) 5691 member = CXXCopyAssignment; 5692 else if (!RDecl->hasTrivialDestructor()) 5693 member = CXXDestructor; 5694 5695 if (member != CXXInvalid) { 5696 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5697 DiagnoseNontrivial(RT, member); 5698 NewFD->setInvalidDecl(); 5699 } 5700 } 5701 } 5702 } 5703 5704 // FIXME: We need to pass in the attributes given an AST 5705 // representation, not a parser representation. 5706 if (D) 5707 // FIXME: What to pass instead of TUScope? 5708 ProcessDeclAttributes(TUScope, NewFD, *D); 5709 5710 if (T.isObjCGCWeak()) 5711 Diag(Loc, diag::warn_attribute_weak_on_field); 5712 5713 NewFD->setAccess(AS); 5714 5715 // C++ [dcl.init.aggr]p1: 5716 // An aggregate is an array or a class (clause 9) with [...] no 5717 // private or protected non-static data members (clause 11). 5718 // A POD must be an aggregate. 5719 if (getLangOptions().CPlusPlus && 5720 (AS == AS_private || AS == AS_protected)) { 5721 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5722 CXXRecord->setAggregate(false); 5723 CXXRecord->setPOD(false); 5724 } 5725 5726 return NewFD; 5727} 5728 5729/// DiagnoseNontrivial - Given that a class has a non-trivial 5730/// special member, figure out why. 5731void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5732 QualType QT(T, 0U); 5733 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5734 5735 // Check whether the member was user-declared. 5736 switch (member) { 5737 case CXXInvalid: 5738 break; 5739 5740 case CXXConstructor: 5741 if (RD->hasUserDeclaredConstructor()) { 5742 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5743 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5744 const FunctionDecl *body = 0; 5745 ci->getBody(body); 5746 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5747 SourceLocation CtorLoc = ci->getLocation(); 5748 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5749 return; 5750 } 5751 } 5752 5753 assert(0 && "found no user-declared constructors"); 5754 return; 5755 } 5756 break; 5757 5758 case CXXCopyConstructor: 5759 if (RD->hasUserDeclaredCopyConstructor()) { 5760 SourceLocation CtorLoc = 5761 RD->getCopyConstructor(Context, 0)->getLocation(); 5762 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5763 return; 5764 } 5765 break; 5766 5767 case CXXCopyAssignment: 5768 if (RD->hasUserDeclaredCopyAssignment()) { 5769 // FIXME: this should use the location of the copy 5770 // assignment, not the type. 5771 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5772 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5773 return; 5774 } 5775 break; 5776 5777 case CXXDestructor: 5778 if (RD->hasUserDeclaredDestructor()) { 5779 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5780 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5781 return; 5782 } 5783 break; 5784 } 5785 5786 typedef CXXRecordDecl::base_class_iterator base_iter; 5787 5788 // Virtual bases and members inhibit trivial copying/construction, 5789 // but not trivial destruction. 5790 if (member != CXXDestructor) { 5791 // Check for virtual bases. vbases includes indirect virtual bases, 5792 // so we just iterate through the direct bases. 5793 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5794 if (bi->isVirtual()) { 5795 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5796 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5797 return; 5798 } 5799 5800 // Check for virtual methods. 5801 typedef CXXRecordDecl::method_iterator meth_iter; 5802 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5803 ++mi) { 5804 if (mi->isVirtual()) { 5805 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5806 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5807 return; 5808 } 5809 } 5810 } 5811 5812 bool (CXXRecordDecl::*hasTrivial)() const; 5813 switch (member) { 5814 case CXXConstructor: 5815 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5816 case CXXCopyConstructor: 5817 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5818 case CXXCopyAssignment: 5819 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5820 case CXXDestructor: 5821 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5822 default: 5823 assert(0 && "unexpected special member"); return; 5824 } 5825 5826 // Check for nontrivial bases (and recurse). 5827 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5828 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5829 assert(BaseRT && "Don't know how to handle dependent bases"); 5830 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5831 if (!(BaseRecTy->*hasTrivial)()) { 5832 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5833 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5834 DiagnoseNontrivial(BaseRT, member); 5835 return; 5836 } 5837 } 5838 5839 // Check for nontrivial members (and recurse). 5840 typedef RecordDecl::field_iterator field_iter; 5841 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5842 ++fi) { 5843 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5844 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5845 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5846 5847 if (!(EltRD->*hasTrivial)()) { 5848 SourceLocation FLoc = (*fi)->getLocation(); 5849 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5850 DiagnoseNontrivial(EltRT, member); 5851 return; 5852 } 5853 } 5854 } 5855 5856 assert(0 && "found no explanation for non-trivial member"); 5857} 5858 5859/// TranslateIvarVisibility - Translate visibility from a token ID to an 5860/// AST enum value. 5861static ObjCIvarDecl::AccessControl 5862TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5863 switch (ivarVisibility) { 5864 default: assert(0 && "Unknown visitibility kind"); 5865 case tok::objc_private: return ObjCIvarDecl::Private; 5866 case tok::objc_public: return ObjCIvarDecl::Public; 5867 case tok::objc_protected: return ObjCIvarDecl::Protected; 5868 case tok::objc_package: return ObjCIvarDecl::Package; 5869 } 5870} 5871 5872/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5873/// in order to create an IvarDecl object for it. 5874Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5875 SourceLocation DeclStart, 5876 DeclPtrTy IntfDecl, 5877 Declarator &D, ExprTy *BitfieldWidth, 5878 tok::ObjCKeywordKind Visibility) { 5879 5880 IdentifierInfo *II = D.getIdentifier(); 5881 Expr *BitWidth = (Expr*)BitfieldWidth; 5882 SourceLocation Loc = DeclStart; 5883 if (II) Loc = D.getIdentifierLoc(); 5884 5885 // FIXME: Unnamed fields can be handled in various different ways, for 5886 // example, unnamed unions inject all members into the struct namespace! 5887 5888 TypeSourceInfo *TInfo = 0; 5889 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5890 5891 if (BitWidth) { 5892 // 6.7.2.1p3, 6.7.2.1p4 5893 if (VerifyBitField(Loc, II, T, BitWidth)) { 5894 D.setInvalidType(); 5895 DeleteExpr(BitWidth); 5896 BitWidth = 0; 5897 } 5898 } else { 5899 // Not a bitfield. 5900 5901 // validate II. 5902 5903 } 5904 if (T->isReferenceType()) { 5905 Diag(Loc, diag::err_ivar_reference_type); 5906 D.setInvalidType(); 5907 } 5908 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5909 // than a variably modified type. 5910 else if (T->isVariablyModifiedType()) { 5911 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5912 D.setInvalidType(); 5913 } 5914 5915 // Get the visibility (access control) for this ivar. 5916 ObjCIvarDecl::AccessControl ac = 5917 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5918 : ObjCIvarDecl::None; 5919 // Must set ivar's DeclContext to its enclosing interface. 5920 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 5921 ObjCContainerDecl *EnclosingContext; 5922 if (ObjCImplementationDecl *IMPDecl = 5923 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5924 // Case of ivar declared in an implementation. Context is that of its class. 5925 EnclosingContext = IMPDecl->getClassInterface(); 5926 assert(EnclosingContext && "Implementation has no class interface!"); 5927 } else { 5928 if (ObjCCategoryDecl *CDecl = 5929 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 5930 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 5931 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 5932 return DeclPtrTy(); 5933 } 5934 } 5935 EnclosingContext = EnclosingDecl; 5936 } 5937 5938 // Construct the decl. 5939 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5940 EnclosingContext, Loc, II, T, 5941 TInfo, ac, (Expr *)BitfieldWidth); 5942 5943 if (II) { 5944 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5945 ForRedeclaration); 5946 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5947 && !isa<TagDecl>(PrevDecl)) { 5948 Diag(Loc, diag::err_duplicate_member) << II; 5949 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5950 NewID->setInvalidDecl(); 5951 } 5952 } 5953 5954 // Process attributes attached to the ivar. 5955 ProcessDeclAttributes(S, NewID, D); 5956 5957 if (D.isInvalidType()) 5958 NewID->setInvalidDecl(); 5959 5960 if (II) { 5961 // FIXME: When interfaces are DeclContexts, we'll need to add 5962 // these to the interface. 5963 S->AddDecl(DeclPtrTy::make(NewID)); 5964 IdResolver.AddDecl(NewID); 5965 } 5966 5967 return DeclPtrTy::make(NewID); 5968} 5969 5970void Sema::ActOnFields(Scope* S, 5971 SourceLocation RecLoc, DeclPtrTy RecDecl, 5972 DeclPtrTy *Fields, unsigned NumFields, 5973 SourceLocation LBrac, SourceLocation RBrac, 5974 AttributeList *Attr) { 5975 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5976 assert(EnclosingDecl && "missing record or interface decl"); 5977 5978 // If the decl this is being inserted into is invalid, then it may be a 5979 // redeclaration or some other bogus case. Don't try to add fields to it. 5980 if (EnclosingDecl->isInvalidDecl()) { 5981 // FIXME: Deallocate fields? 5982 return; 5983 } 5984 5985 5986 // Verify that all the fields are okay. 5987 unsigned NumNamedMembers = 0; 5988 llvm::SmallVector<FieldDecl*, 32> RecFields; 5989 5990 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5991 for (unsigned i = 0; i != NumFields; ++i) { 5992 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5993 5994 // Get the type for the field. 5995 Type *FDTy = FD->getType().getTypePtr(); 5996 5997 if (!FD->isAnonymousStructOrUnion()) { 5998 // Remember all fields written by the user. 5999 RecFields.push_back(FD); 6000 } 6001 6002 // If the field is already invalid for some reason, don't emit more 6003 // diagnostics about it. 6004 if (FD->isInvalidDecl()) { 6005 EnclosingDecl->setInvalidDecl(); 6006 continue; 6007 } 6008 6009 // C99 6.7.2.1p2: 6010 // A structure or union shall not contain a member with 6011 // incomplete or function type (hence, a structure shall not 6012 // contain an instance of itself, but may contain a pointer to 6013 // an instance of itself), except that the last member of a 6014 // structure with more than one named member may have incomplete 6015 // array type; such a structure (and any union containing, 6016 // possibly recursively, a member that is such a structure) 6017 // shall not be a member of a structure or an element of an 6018 // array. 6019 if (FDTy->isFunctionType()) { 6020 // Field declared as a function. 6021 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6022 << FD->getDeclName(); 6023 FD->setInvalidDecl(); 6024 EnclosingDecl->setInvalidDecl(); 6025 continue; 6026 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6027 Record && Record->isStruct()) { 6028 // Flexible array member. 6029 if (NumNamedMembers < 1) { 6030 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6031 << FD->getDeclName(); 6032 FD->setInvalidDecl(); 6033 EnclosingDecl->setInvalidDecl(); 6034 continue; 6035 } 6036 // Okay, we have a legal flexible array member at the end of the struct. 6037 if (Record) 6038 Record->setHasFlexibleArrayMember(true); 6039 } else if (!FDTy->isDependentType() && 6040 RequireCompleteType(FD->getLocation(), FD->getType(), 6041 diag::err_field_incomplete)) { 6042 // Incomplete type 6043 FD->setInvalidDecl(); 6044 EnclosingDecl->setInvalidDecl(); 6045 continue; 6046 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6047 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6048 // If this is a member of a union, then entire union becomes "flexible". 6049 if (Record && Record->isUnion()) { 6050 Record->setHasFlexibleArrayMember(true); 6051 } else { 6052 // If this is a struct/class and this is not the last element, reject 6053 // it. Note that GCC supports variable sized arrays in the middle of 6054 // structures. 6055 if (i != NumFields-1) 6056 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6057 << FD->getDeclName() << FD->getType(); 6058 else { 6059 // We support flexible arrays at the end of structs in 6060 // other structs as an extension. 6061 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6062 << FD->getDeclName(); 6063 if (Record) 6064 Record->setHasFlexibleArrayMember(true); 6065 } 6066 } 6067 } 6068 if (Record && FDTTy->getDecl()->hasObjectMember()) 6069 Record->setHasObjectMember(true); 6070 } else if (FDTy->isObjCInterfaceType()) { 6071 /// A field cannot be an Objective-c object 6072 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6073 FD->setInvalidDecl(); 6074 EnclosingDecl->setInvalidDecl(); 6075 continue; 6076 } else if (getLangOptions().ObjC1 && 6077 getLangOptions().getGCMode() != LangOptions::NonGC && 6078 Record && 6079 (FD->getType()->isObjCObjectPointerType() || 6080 FD->getType().isObjCGCStrong())) 6081 Record->setHasObjectMember(true); 6082 // Keep track of the number of named members. 6083 if (FD->getIdentifier()) 6084 ++NumNamedMembers; 6085 } 6086 6087 // Okay, we successfully defined 'Record'. 6088 if (Record) { 6089 Record->completeDefinition(); 6090 } else { 6091 ObjCIvarDecl **ClsFields = 6092 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6093 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6094 ID->setLocEnd(RBrac); 6095 // Add ivar's to class's DeclContext. 6096 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6097 ClsFields[i]->setLexicalDeclContext(ID); 6098 ID->addDecl(ClsFields[i]); 6099 } 6100 // Must enforce the rule that ivars in the base classes may not be 6101 // duplicates. 6102 if (ID->getSuperClass()) 6103 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6104 } else if (ObjCImplementationDecl *IMPDecl = 6105 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6106 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6107 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6108 // Ivar declared in @implementation never belongs to the implementation. 6109 // Only it is in implementation's lexical context. 6110 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6111 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6112 } else if (ObjCCategoryDecl *CDecl = 6113 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6114 // case of ivars in class extension; all other cases have been 6115 // reported as errors elsewhere. 6116 // FIXME. Class extension does not have a LocEnd field. 6117 // CDecl->setLocEnd(RBrac); 6118 // Add ivar's to class extension's DeclContext. 6119 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6120 ClsFields[i]->setLexicalDeclContext(CDecl); 6121 CDecl->addDecl(ClsFields[i]); 6122 } 6123 } 6124 } 6125 6126 if (Attr) 6127 ProcessDeclAttributeList(S, Record, Attr); 6128} 6129 6130/// \brief Determine whether the given integral value is representable within 6131/// the given type T. 6132static bool isRepresentableIntegerValue(ASTContext &Context, 6133 llvm::APSInt &Value, 6134 QualType T) { 6135 assert(T->isIntegralType() && "Integral type required!"); 6136 unsigned BitWidth = Context.getIntWidth(T); 6137 6138 if (Value.isUnsigned() || Value.isNonNegative()) 6139 return Value.getActiveBits() < BitWidth; 6140 6141 return Value.getMinSignedBits() <= BitWidth; 6142} 6143 6144// \brief Given an integral type, return the next larger integral type 6145// (or a NULL type of no such type exists). 6146static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6147 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6148 // enum checking below. 6149 assert(T->isIntegralType() && "Integral type required!"); 6150 const unsigned NumTypes = 4; 6151 QualType SignedIntegralTypes[NumTypes] = { 6152 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6153 }; 6154 QualType UnsignedIntegralTypes[NumTypes] = { 6155 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6156 Context.UnsignedLongLongTy 6157 }; 6158 6159 unsigned BitWidth = Context.getTypeSize(T); 6160 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6161 : UnsignedIntegralTypes; 6162 for (unsigned I = 0; I != NumTypes; ++I) 6163 if (Context.getTypeSize(Types[I]) > BitWidth) 6164 return Types[I]; 6165 6166 return QualType(); 6167} 6168 6169EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6170 EnumConstantDecl *LastEnumConst, 6171 SourceLocation IdLoc, 6172 IdentifierInfo *Id, 6173 ExprArg val) { 6174 Expr *Val = (Expr *)val.get(); 6175 6176 unsigned IntWidth = Context.Target.getIntWidth(); 6177 llvm::APSInt EnumVal(IntWidth); 6178 QualType EltTy; 6179 if (Val) { 6180 if (Enum->isDependentType() || Val->isTypeDependent()) 6181 EltTy = Context.DependentTy; 6182 else { 6183 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6184 SourceLocation ExpLoc; 6185 if (!Val->isValueDependent() && 6186 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6187 Val = 0; 6188 } else { 6189 if (!getLangOptions().CPlusPlus) { 6190 // C99 6.7.2.2p2: 6191 // The expression that defines the value of an enumeration constant 6192 // shall be an integer constant expression that has a value 6193 // representable as an int. 6194 6195 // Complain if the value is not representable in an int. 6196 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6197 Diag(IdLoc, diag::ext_enum_value_not_int) 6198 << EnumVal.toString(10) << Val->getSourceRange() 6199 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6200 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6201 // Force the type of the expression to 'int'. 6202 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6203 6204 if (Val != val.get()) { 6205 val.release(); 6206 val = Val; 6207 } 6208 } 6209 } 6210 6211 // C++0x [dcl.enum]p5: 6212 // If the underlying type is not fixed, the type of each enumerator 6213 // is the type of its initializing value: 6214 // - If an initializer is specified for an enumerator, the 6215 // initializing value has the same type as the expression. 6216 EltTy = Val->getType(); 6217 } 6218 } 6219 } 6220 6221 if (!Val) { 6222 if (Enum->isDependentType()) 6223 EltTy = Context.DependentTy; 6224 else if (!LastEnumConst) { 6225 // C++0x [dcl.enum]p5: 6226 // If the underlying type is not fixed, the type of each enumerator 6227 // is the type of its initializing value: 6228 // - If no initializer is specified for the first enumerator, the 6229 // initializing value has an unspecified integral type. 6230 // 6231 // GCC uses 'int' for its unspecified integral type, as does 6232 // C99 6.7.2.2p3. 6233 EltTy = Context.IntTy; 6234 } else { 6235 // Assign the last value + 1. 6236 EnumVal = LastEnumConst->getInitVal(); 6237 ++EnumVal; 6238 EltTy = LastEnumConst->getType(); 6239 6240 // Check for overflow on increment. 6241 if (EnumVal < LastEnumConst->getInitVal()) { 6242 // C++0x [dcl.enum]p5: 6243 // If the underlying type is not fixed, the type of each enumerator 6244 // is the type of its initializing value: 6245 // 6246 // - Otherwise the type of the initializing value is the same as 6247 // the type of the initializing value of the preceding enumerator 6248 // unless the incremented value is not representable in that type, 6249 // in which case the type is an unspecified integral type 6250 // sufficient to contain the incremented value. If no such type 6251 // exists, the program is ill-formed. 6252 QualType T = getNextLargerIntegralType(Context, EltTy); 6253 if (T.isNull()) { 6254 // There is no integral type larger enough to represent this 6255 // value. Complain, then allow the value to wrap around. 6256 EnumVal = LastEnumConst->getInitVal(); 6257 EnumVal.zext(EnumVal.getBitWidth() * 2); 6258 Diag(IdLoc, diag::warn_enumerator_too_large) 6259 << EnumVal.toString(10); 6260 } else { 6261 EltTy = T; 6262 } 6263 6264 // Retrieve the last enumerator's value, extent that type to the 6265 // type that is supposed to be large enough to represent the incremented 6266 // value, then increment. 6267 EnumVal = LastEnumConst->getInitVal(); 6268 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6269 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6270 ++EnumVal; 6271 6272 // If we're not in C++, diagnose the overflow of enumerator values, 6273 // which in C99 means that the enumerator value is not representable in 6274 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6275 // permits enumerator values that are representable in some larger 6276 // integral type. 6277 if (!getLangOptions().CPlusPlus && !T.isNull()) 6278 Diag(IdLoc, diag::warn_enum_value_overflow); 6279 } else if (!getLangOptions().CPlusPlus && 6280 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6281 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6282 Diag(IdLoc, diag::ext_enum_value_not_int) 6283 << EnumVal.toString(10) << 1; 6284 } 6285 } 6286 } 6287 6288 if (!EltTy->isDependentType()) { 6289 // Make the enumerator value match the signedness and size of the 6290 // enumerator's type. 6291 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6292 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6293 } 6294 6295 val.release(); 6296 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6297 Val, EnumVal); 6298} 6299 6300 6301Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6302 DeclPtrTy lastEnumConst, 6303 SourceLocation IdLoc, 6304 IdentifierInfo *Id, 6305 SourceLocation EqualLoc, ExprTy *val) { 6306 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6307 EnumConstantDecl *LastEnumConst = 6308 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6309 Expr *Val = static_cast<Expr*>(val); 6310 6311 // The scope passed in may not be a decl scope. Zip up the scope tree until 6312 // we find one that is. 6313 S = getNonFieldDeclScope(S); 6314 6315 // Verify that there isn't already something declared with this name in this 6316 // scope. 6317 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6318 ForRedeclaration); 6319 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6320 // Maybe we will complain about the shadowed template parameter. 6321 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6322 // Just pretend that we didn't see the previous declaration. 6323 PrevDecl = 0; 6324 } 6325 6326 if (PrevDecl) { 6327 // When in C++, we may get a TagDecl with the same name; in this case the 6328 // enum constant will 'hide' the tag. 6329 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6330 "Received TagDecl when not in C++!"); 6331 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6332 if (isa<EnumConstantDecl>(PrevDecl)) 6333 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6334 else 6335 Diag(IdLoc, diag::err_redefinition) << Id; 6336 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6337 if (Val) Val->Destroy(Context); 6338 return DeclPtrTy(); 6339 } 6340 } 6341 6342 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6343 IdLoc, Id, Owned(Val)); 6344 6345 // Register this decl in the current scope stack. 6346 if (New) { 6347 New->setAccess(TheEnumDecl->getAccess()); 6348 PushOnScopeChains(New, S); 6349 } 6350 6351 return DeclPtrTy::make(New); 6352} 6353 6354void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6355 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6356 DeclPtrTy *Elements, unsigned NumElements, 6357 Scope *S, AttributeList *Attr) { 6358 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6359 QualType EnumType = Context.getTypeDeclType(Enum); 6360 6361 if (Attr) 6362 ProcessDeclAttributeList(S, Enum, Attr); 6363 6364 if (Enum->isDependentType()) { 6365 for (unsigned i = 0; i != NumElements; ++i) { 6366 EnumConstantDecl *ECD = 6367 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6368 if (!ECD) continue; 6369 6370 ECD->setType(EnumType); 6371 } 6372 6373 Enum->completeDefinition(Context.DependentTy, Context.DependentTy); 6374 return; 6375 } 6376 6377 // TODO: If the result value doesn't fit in an int, it must be a long or long 6378 // long value. ISO C does not support this, but GCC does as an extension, 6379 // emit a warning. 6380 unsigned IntWidth = Context.Target.getIntWidth(); 6381 unsigned CharWidth = Context.Target.getCharWidth(); 6382 unsigned ShortWidth = Context.Target.getShortWidth(); 6383 6384 // Verify that all the values are okay, compute the size of the values, and 6385 // reverse the list. 6386 unsigned NumNegativeBits = 0; 6387 unsigned NumPositiveBits = 0; 6388 6389 // Keep track of whether all elements have type int. 6390 bool AllElementsInt = true; 6391 6392 for (unsigned i = 0; i != NumElements; ++i) { 6393 EnumConstantDecl *ECD = 6394 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6395 if (!ECD) continue; // Already issued a diagnostic. 6396 6397 const llvm::APSInt &InitVal = ECD->getInitVal(); 6398 6399 // Keep track of the size of positive and negative values. 6400 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6401 NumPositiveBits = std::max(NumPositiveBits, 6402 (unsigned)InitVal.getActiveBits()); 6403 else 6404 NumNegativeBits = std::max(NumNegativeBits, 6405 (unsigned)InitVal.getMinSignedBits()); 6406 6407 // Keep track of whether every enum element has type int (very commmon). 6408 if (AllElementsInt) 6409 AllElementsInt = ECD->getType() == Context.IntTy; 6410 } 6411 6412 // Figure out the type that should be used for this enum. 6413 // FIXME: Support -fshort-enums. 6414 QualType BestType; 6415 unsigned BestWidth; 6416 6417 // C++0x N3000 [conv.prom]p3: 6418 // An rvalue of an unscoped enumeration type whose underlying 6419 // type is not fixed can be converted to an rvalue of the first 6420 // of the following types that can represent all the values of 6421 // the enumeration: int, unsigned int, long int, unsigned long 6422 // int, long long int, or unsigned long long int. 6423 // C99 6.4.4.3p2: 6424 // An identifier declared as an enumeration constant has type int. 6425 // The C99 rule is modified by a gcc extension 6426 QualType BestPromotionType; 6427 6428 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6429 6430 if (NumNegativeBits) { 6431 // If there is a negative value, figure out the smallest integer type (of 6432 // int/long/longlong) that fits. 6433 // If it's packed, check also if it fits a char or a short. 6434 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6435 BestType = Context.SignedCharTy; 6436 BestWidth = CharWidth; 6437 } else if (Packed && NumNegativeBits <= ShortWidth && 6438 NumPositiveBits < ShortWidth) { 6439 BestType = Context.ShortTy; 6440 BestWidth = ShortWidth; 6441 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6442 BestType = Context.IntTy; 6443 BestWidth = IntWidth; 6444 } else { 6445 BestWidth = Context.Target.getLongWidth(); 6446 6447 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6448 BestType = Context.LongTy; 6449 } else { 6450 BestWidth = Context.Target.getLongLongWidth(); 6451 6452 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6453 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6454 BestType = Context.LongLongTy; 6455 } 6456 } 6457 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6458 } else { 6459 // If there is no negative value, figure out the smallest type that fits 6460 // all of the enumerator values. 6461 // If it's packed, check also if it fits a char or a short. 6462 if (Packed && NumPositiveBits <= CharWidth) { 6463 BestType = Context.UnsignedCharTy; 6464 BestPromotionType = Context.IntTy; 6465 BestWidth = CharWidth; 6466 } else if (Packed && NumPositiveBits <= ShortWidth) { 6467 BestType = Context.UnsignedShortTy; 6468 BestPromotionType = Context.IntTy; 6469 BestWidth = ShortWidth; 6470 } else if (NumPositiveBits <= IntWidth) { 6471 BestType = Context.UnsignedIntTy; 6472 BestWidth = IntWidth; 6473 BestPromotionType 6474 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6475 ? Context.UnsignedIntTy : Context.IntTy; 6476 } else if (NumPositiveBits <= 6477 (BestWidth = Context.Target.getLongWidth())) { 6478 BestType = Context.UnsignedLongTy; 6479 BestPromotionType 6480 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6481 ? Context.UnsignedLongTy : Context.LongTy; 6482 } else { 6483 BestWidth = Context.Target.getLongLongWidth(); 6484 assert(NumPositiveBits <= BestWidth && 6485 "How could an initializer get larger than ULL?"); 6486 BestType = Context.UnsignedLongLongTy; 6487 BestPromotionType 6488 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6489 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6490 } 6491 } 6492 6493 // Loop over all of the enumerator constants, changing their types to match 6494 // the type of the enum if needed. 6495 for (unsigned i = 0; i != NumElements; ++i) { 6496 EnumConstantDecl *ECD = 6497 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6498 if (!ECD) continue; // Already issued a diagnostic. 6499 6500 // Standard C says the enumerators have int type, but we allow, as an 6501 // extension, the enumerators to be larger than int size. If each 6502 // enumerator value fits in an int, type it as an int, otherwise type it the 6503 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6504 // that X has type 'int', not 'unsigned'. 6505 6506 // Determine whether the value fits into an int. 6507 llvm::APSInt InitVal = ECD->getInitVal(); 6508 6509 // If it fits into an integer type, force it. Otherwise force it to match 6510 // the enum decl type. 6511 QualType NewTy; 6512 unsigned NewWidth; 6513 bool NewSign; 6514 if (!getLangOptions().CPlusPlus && 6515 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6516 NewTy = Context.IntTy; 6517 NewWidth = IntWidth; 6518 NewSign = true; 6519 } else if (ECD->getType() == BestType) { 6520 // Already the right type! 6521 if (getLangOptions().CPlusPlus) 6522 // C++ [dcl.enum]p4: Following the closing brace of an 6523 // enum-specifier, each enumerator has the type of its 6524 // enumeration. 6525 ECD->setType(EnumType); 6526 continue; 6527 } else { 6528 NewTy = BestType; 6529 NewWidth = BestWidth; 6530 NewSign = BestType->isSignedIntegerType(); 6531 } 6532 6533 // Adjust the APSInt value. 6534 InitVal.extOrTrunc(NewWidth); 6535 InitVal.setIsSigned(NewSign); 6536 ECD->setInitVal(InitVal); 6537 6538 // Adjust the Expr initializer and type. 6539 if (ECD->getInitExpr()) 6540 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6541 CastExpr::CK_IntegralCast, 6542 ECD->getInitExpr(), 6543 CXXBaseSpecifierArray(), 6544 /*isLvalue=*/false)); 6545 if (getLangOptions().CPlusPlus) 6546 // C++ [dcl.enum]p4: Following the closing brace of an 6547 // enum-specifier, each enumerator has the type of its 6548 // enumeration. 6549 ECD->setType(EnumType); 6550 else 6551 ECD->setType(NewTy); 6552 } 6553 6554 Enum->completeDefinition(BestType, BestPromotionType); 6555} 6556 6557Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6558 ExprArg expr) { 6559 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6560 6561 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6562 Loc, AsmString); 6563 CurContext->addDecl(New); 6564 return DeclPtrTy::make(New); 6565} 6566 6567void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6568 SourceLocation PragmaLoc, 6569 SourceLocation NameLoc) { 6570 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6571 6572 if (PrevDecl) { 6573 PrevDecl->addAttr(::new (Context) WeakAttr()); 6574 } else { 6575 (void)WeakUndeclaredIdentifiers.insert( 6576 std::pair<IdentifierInfo*,WeakInfo> 6577 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6578 } 6579} 6580 6581void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6582 IdentifierInfo* AliasName, 6583 SourceLocation PragmaLoc, 6584 SourceLocation NameLoc, 6585 SourceLocation AliasNameLoc) { 6586 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6587 LookupOrdinaryName); 6588 WeakInfo W = WeakInfo(Name, NameLoc); 6589 6590 if (PrevDecl) { 6591 if (!PrevDecl->hasAttr<AliasAttr>()) 6592 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6593 DeclApplyPragmaWeak(TUScope, ND, W); 6594 } else { 6595 (void)WeakUndeclaredIdentifiers.insert( 6596 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6597 } 6598} 6599