SemaDecl.cpp revision 9983d2d76c8107672b5907124266f482ba03823f
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isNotEmpty()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, 91 // so build a dependent node to describe the type. 92 return CheckTypenameType(ETK_None, 93 (NestedNameSpecifier *)SS->getScopeRep(), II, 94 SourceLocation(), SS->getRange(), NameLoc 95 ).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && 102 RequireCompleteDeclContext(*SS, LookupCtx)) 103 return 0; 104 } 105 106 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 107 // lookup for class-names. 108 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 109 LookupOrdinaryName; 110 LookupResult Result(*this, &II, NameLoc, Kind); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::NotFoundInCurrentInstantiation: 136 case LookupResult::FoundOverloaded: 137 case LookupResult::FoundUnresolvedValue: 138 Result.suppressDiagnostics(); 139 return 0; 140 141 case LookupResult::Ambiguous: 142 // Recover from type-hiding ambiguities by hiding the type. We'll 143 // do the lookup again when looking for an object, and we can 144 // diagnose the error then. If we don't do this, then the error 145 // about hiding the type will be immediately followed by an error 146 // that only makes sense if the identifier was treated like a type. 147 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 148 Result.suppressDiagnostics(); 149 return 0; 150 } 151 152 // Look to see if we have a type anywhere in the list of results. 153 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 154 Res != ResEnd; ++Res) { 155 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 156 if (!IIDecl || 157 (*Res)->getLocation().getRawEncoding() < 158 IIDecl->getLocation().getRawEncoding()) 159 IIDecl = *Res; 160 } 161 } 162 163 if (!IIDecl) { 164 // None of the entities we found is a type, so there is no way 165 // to even assume that the result is a type. In this case, don't 166 // complain about the ambiguity. The parser will either try to 167 // perform this lookup again (e.g., as an object name), which 168 // will produce the ambiguity, or will complain that it expected 169 // a type name. 170 Result.suppressDiagnostics(); 171 return 0; 172 } 173 174 // We found a type within the ambiguous lookup; diagnose the 175 // ambiguity and then return that type. This might be the right 176 // answer, or it might not be, but it suppresses any attempt to 177 // perform the name lookup again. 178 break; 179 180 case LookupResult::Found: 181 IIDecl = Result.getFoundDecl(); 182 break; 183 } 184 185 assert(IIDecl && "Didn't find decl"); 186 187 QualType T; 188 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 189 DiagnoseUseOfDecl(IIDecl, NameLoc); 190 191 if (T.isNull()) 192 T = Context.getTypeDeclType(TD); 193 194 if (SS) 195 T = getElaboratedType(ETK_None, *SS, T); 196 197 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 198 T = Context.getObjCInterfaceType(IDecl); 199 } else { 200 // If it's not plausibly a type, suppress diagnostics. 201 Result.suppressDiagnostics(); 202 return 0; 203 } 204 205 return T.getAsOpaquePtr(); 206} 207 208/// isTagName() - This method is called *for error recovery purposes only* 209/// to determine if the specified name is a valid tag name ("struct foo"). If 210/// so, this returns the TST for the tag corresponding to it (TST_enum, 211/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 212/// where the user forgot to specify the tag. 213DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 214 // Do a tag name lookup in this scope. 215 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 216 LookupName(R, S, false); 217 R.suppressDiagnostics(); 218 if (R.getResultKind() == LookupResult::Found) 219 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 220 switch (TD->getTagKind()) { 221 default: return DeclSpec::TST_unspecified; 222 case TTK_Struct: return DeclSpec::TST_struct; 223 case TTK_Union: return DeclSpec::TST_union; 224 case TTK_Class: return DeclSpec::TST_class; 225 case TTK_Enum: return DeclSpec::TST_enum; 226 } 227 } 228 229 return DeclSpec::TST_unspecified; 230} 231 232bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 233 SourceLocation IILoc, 234 Scope *S, 235 CXXScopeSpec *SS, 236 TypeTy *&SuggestedType) { 237 // We don't have anything to suggest (yet). 238 SuggestedType = 0; 239 240 // There may have been a typo in the name of the type. Look up typo 241 // results, in case we have something that we can suggest. 242 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 243 NotForRedeclaration); 244 245 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 246 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 247 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 248 !Result->isInvalidDecl()) { 249 // We found a similarly-named type or interface; suggest that. 250 if (!SS || !SS->isSet()) 251 Diag(IILoc, diag::err_unknown_typename_suggest) 252 << &II << Lookup.getLookupName() 253 << FixItHint::CreateReplacement(SourceRange(IILoc), 254 Result->getNameAsString()); 255 else if (DeclContext *DC = computeDeclContext(*SS, false)) 256 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 257 << &II << DC << Lookup.getLookupName() << SS->getRange() 258 << FixItHint::CreateReplacement(SourceRange(IILoc), 259 Result->getNameAsString()); 260 else 261 llvm_unreachable("could not have corrected a typo here"); 262 263 Diag(Result->getLocation(), diag::note_previous_decl) 264 << Result->getDeclName(); 265 266 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 267 return true; 268 } 269 } else if (Lookup.empty()) { 270 // We corrected to a keyword. 271 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 272 Diag(IILoc, diag::err_unknown_typename_suggest) 273 << &II << Corrected; 274 return true; 275 } 276 } 277 278 if (getLangOptions().CPlusPlus) { 279 // See if II is a class template that the user forgot to pass arguments to. 280 UnqualifiedId Name; 281 Name.setIdentifier(&II, IILoc); 282 CXXScopeSpec EmptySS; 283 TemplateTy TemplateResult; 284 bool MemberOfUnknownSpecialization; 285 if (isTemplateName(S, SS ? *SS : EmptySS, Name, 0, true, TemplateResult, 286 MemberOfUnknownSpecialization) == TNK_Type_template) { 287 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 288 Diag(IILoc, diag::err_template_missing_args) << TplName; 289 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 290 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 291 << TplDecl->getTemplateParameters()->getSourceRange(); 292 } 293 return true; 294 } 295 } 296 297 // FIXME: Should we move the logic that tries to recover from a missing tag 298 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 299 300 if (!SS || (!SS->isSet() && !SS->isInvalid())) 301 Diag(IILoc, diag::err_unknown_typename) << &II; 302 else if (DeclContext *DC = computeDeclContext(*SS, false)) 303 Diag(IILoc, diag::err_typename_nested_not_found) 304 << &II << DC << SS->getRange(); 305 else if (isDependentScopeSpecifier(*SS)) { 306 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 307 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 308 << SourceRange(SS->getRange().getBegin(), IILoc) 309 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 310 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 311 } else { 312 assert(SS && SS->isInvalid() && 313 "Invalid scope specifier has already been diagnosed"); 314 } 315 316 return true; 317} 318 319// Determines the context to return to after temporarily entering a 320// context. This depends in an unnecessarily complicated way on the 321// exact ordering of callbacks from the parser. 322DeclContext *Sema::getContainingDC(DeclContext *DC) { 323 324 // Functions defined inline within classes aren't parsed until we've 325 // finished parsing the top-level class, so the top-level class is 326 // the context we'll need to return to. 327 if (isa<FunctionDecl>(DC)) { 328 DC = DC->getLexicalParent(); 329 330 // A function not defined within a class will always return to its 331 // lexical context. 332 if (!isa<CXXRecordDecl>(DC)) 333 return DC; 334 335 // A C++ inline method/friend is parsed *after* the topmost class 336 // it was declared in is fully parsed ("complete"); the topmost 337 // class is the context we need to return to. 338 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 339 DC = RD; 340 341 // Return the declaration context of the topmost class the inline method is 342 // declared in. 343 return DC; 344 } 345 346 // ObjCMethodDecls are parsed (for some reason) outside the context 347 // of the class. 348 if (isa<ObjCMethodDecl>(DC)) 349 return DC->getLexicalParent()->getLexicalParent(); 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 assert(CurContext && "Popped translation unit!"); 366} 367 368/// EnterDeclaratorContext - Used when we must lookup names in the context 369/// of a declarator's nested name specifier. 370/// 371void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 372 // C++0x [basic.lookup.unqual]p13: 373 // A name used in the definition of a static data member of class 374 // X (after the qualified-id of the static member) is looked up as 375 // if the name was used in a member function of X. 376 // C++0x [basic.lookup.unqual]p14: 377 // If a variable member of a namespace is defined outside of the 378 // scope of its namespace then any name used in the definition of 379 // the variable member (after the declarator-id) is looked up as 380 // if the definition of the variable member occurred in its 381 // namespace. 382 // Both of these imply that we should push a scope whose context 383 // is the semantic context of the declaration. We can't use 384 // PushDeclContext here because that context is not necessarily 385 // lexically contained in the current context. Fortunately, 386 // the containing scope should have the appropriate information. 387 388 assert(!S->getEntity() && "scope already has entity"); 389 390#ifndef NDEBUG 391 Scope *Ancestor = S->getParent(); 392 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 393 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 394#endif 395 396 CurContext = DC; 397 S->setEntity(DC); 398} 399 400void Sema::ExitDeclaratorContext(Scope *S) { 401 assert(S->getEntity() == CurContext && "Context imbalance!"); 402 403 // Switch back to the lexical context. The safety of this is 404 // enforced by an assert in EnterDeclaratorContext. 405 Scope *Ancestor = S->getParent(); 406 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 407 CurContext = (DeclContext*) Ancestor->getEntity(); 408 409 // We don't need to do anything with the scope, which is going to 410 // disappear. 411} 412 413/// \brief Determine whether we allow overloading of the function 414/// PrevDecl with another declaration. 415/// 416/// This routine determines whether overloading is possible, not 417/// whether some new function is actually an overload. It will return 418/// true in C++ (where we can always provide overloads) or, as an 419/// extension, in C when the previous function is already an 420/// overloaded function declaration or has the "overloadable" 421/// attribute. 422static bool AllowOverloadingOfFunction(LookupResult &Previous, 423 ASTContext &Context) { 424 if (Context.getLangOptions().CPlusPlus) 425 return true; 426 427 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 428 return true; 429 430 return (Previous.getResultKind() == LookupResult::Found 431 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 432} 433 434/// Add this decl to the scope shadowed decl chains. 435void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 436 // Move up the scope chain until we find the nearest enclosing 437 // non-transparent context. The declaration will be introduced into this 438 // scope. 439 while (S->getEntity() && 440 ((DeclContext *)S->getEntity())->isTransparentContext()) 441 S = S->getParent(); 442 443 // Add scoped declarations into their context, so that they can be 444 // found later. Declarations without a context won't be inserted 445 // into any context. 446 if (AddToContext) 447 CurContext->addDecl(D); 448 449 // Out-of-line definitions shouldn't be pushed into scope in C++. 450 // Out-of-line variable and function definitions shouldn't even in C. 451 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 452 D->isOutOfLine()) 453 return; 454 455 // Template instantiations should also not be pushed into scope. 456 if (isa<FunctionDecl>(D) && 457 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 458 return; 459 460 // If this replaces anything in the current scope, 461 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 462 IEnd = IdResolver.end(); 463 for (; I != IEnd; ++I) { 464 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 465 S->RemoveDecl(DeclPtrTy::make(*I)); 466 IdResolver.RemoveDecl(*I); 467 468 // Should only need to replace one decl. 469 break; 470 } 471 } 472 473 S->AddDecl(DeclPtrTy::make(D)); 474 IdResolver.AddDecl(D); 475} 476 477bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 478 return IdResolver.isDeclInScope(D, Ctx, Context, S); 479} 480 481static bool isOutOfScopePreviousDeclaration(NamedDecl *, 482 DeclContext*, 483 ASTContext&); 484 485/// Filters out lookup results that don't fall within the given scope 486/// as determined by isDeclInScope. 487static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 488 DeclContext *Ctx, Scope *S, 489 bool ConsiderLinkage) { 490 LookupResult::Filter F = R.makeFilter(); 491 while (F.hasNext()) { 492 NamedDecl *D = F.next(); 493 494 if (SemaRef.isDeclInScope(D, Ctx, S)) 495 continue; 496 497 if (ConsiderLinkage && 498 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 499 continue; 500 501 F.erase(); 502 } 503 504 F.done(); 505} 506 507static bool isUsingDecl(NamedDecl *D) { 508 return isa<UsingShadowDecl>(D) || 509 isa<UnresolvedUsingTypenameDecl>(D) || 510 isa<UnresolvedUsingValueDecl>(D); 511} 512 513/// Removes using shadow declarations from the lookup results. 514static void RemoveUsingDecls(LookupResult &R) { 515 LookupResult::Filter F = R.makeFilter(); 516 while (F.hasNext()) 517 if (isUsingDecl(F.next())) 518 F.erase(); 519 520 F.done(); 521} 522 523static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 524 if (D->isInvalidDecl()) 525 return false; 526 527 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 528 return false; 529 530 // White-list anything that isn't a local variable. 531 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 532 !D->getDeclContext()->isFunctionOrMethod()) 533 return false; 534 535 // Types of valid local variables should be complete, so this should succeed. 536 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 537 538 // White-list anything with an __attribute__((unused)) type. 539 QualType Ty = VD->getType(); 540 541 // Only look at the outermost level of typedef. 542 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 543 if (TT->getDecl()->hasAttr<UnusedAttr>()) 544 return false; 545 } 546 547 // If we failed to complete the type for some reason, or if the type is 548 // dependent, don't diagnose the variable. 549 if (Ty->isIncompleteType() || Ty->isDependentType()) 550 return false; 551 552 if (const TagType *TT = Ty->getAs<TagType>()) { 553 const TagDecl *Tag = TT->getDecl(); 554 if (Tag->hasAttr<UnusedAttr>()) 555 return false; 556 557 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 558 // FIXME: Checking for the presence of a user-declared constructor 559 // isn't completely accurate; we'd prefer to check that the initializer 560 // has no side effects. 561 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 562 return false; 563 } 564 } 565 566 // TODO: __attribute__((unused)) templates? 567 } 568 569 return true; 570} 571 572void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 573 if (!ShouldDiagnoseUnusedDecl(D)) 574 return; 575 576 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 577 Diag(D->getLocation(), diag::warn_unused_exception_param) 578 << D->getDeclName(); 579 else 580 Diag(D->getLocation(), diag::warn_unused_variable) 581 << D->getDeclName(); 582} 583 584void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 585 if (S->decl_empty()) return; 586 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 587 "Scope shouldn't contain decls!"); 588 589 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 590 I != E; ++I) { 591 Decl *TmpD = (*I).getAs<Decl>(); 592 assert(TmpD && "This decl didn't get pushed??"); 593 594 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 595 NamedDecl *D = cast<NamedDecl>(TmpD); 596 597 if (!D->getDeclName()) continue; 598 599 // Diagnose unused variables in this scope. 600 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 601 DiagnoseUnusedDecl(D); 602 603 // Remove this name from our lexical scope. 604 IdResolver.RemoveDecl(D); 605 } 606} 607 608/// \brief Look for an Objective-C class in the translation unit. 609/// 610/// \param Id The name of the Objective-C class we're looking for. If 611/// typo-correction fixes this name, the Id will be updated 612/// to the fixed name. 613/// 614/// \param IdLoc The location of the name in the translation unit. 615/// 616/// \param TypoCorrection If true, this routine will attempt typo correction 617/// if there is no class with the given name. 618/// 619/// \returns The declaration of the named Objective-C class, or NULL if the 620/// class could not be found. 621ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 622 SourceLocation IdLoc, 623 bool TypoCorrection) { 624 // The third "scope" argument is 0 since we aren't enabling lazy built-in 625 // creation from this context. 626 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 627 628 if (!IDecl && TypoCorrection) { 629 // Perform typo correction at the given location, but only if we 630 // find an Objective-C class name. 631 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 632 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 633 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 634 Diag(IdLoc, diag::err_undef_interface_suggest) 635 << Id << IDecl->getDeclName() 636 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 637 Diag(IDecl->getLocation(), diag::note_previous_decl) 638 << IDecl->getDeclName(); 639 640 Id = IDecl->getIdentifier(); 641 } 642 } 643 644 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 645} 646 647/// getNonFieldDeclScope - Retrieves the innermost scope, starting 648/// from S, where a non-field would be declared. This routine copes 649/// with the difference between C and C++ scoping rules in structs and 650/// unions. For example, the following code is well-formed in C but 651/// ill-formed in C++: 652/// @code 653/// struct S6 { 654/// enum { BAR } e; 655/// }; 656/// 657/// void test_S6() { 658/// struct S6 a; 659/// a.e = BAR; 660/// } 661/// @endcode 662/// For the declaration of BAR, this routine will return a different 663/// scope. The scope S will be the scope of the unnamed enumeration 664/// within S6. In C++, this routine will return the scope associated 665/// with S6, because the enumeration's scope is a transparent 666/// context but structures can contain non-field names. In C, this 667/// routine will return the translation unit scope, since the 668/// enumeration's scope is a transparent context and structures cannot 669/// contain non-field names. 670Scope *Sema::getNonFieldDeclScope(Scope *S) { 671 while (((S->getFlags() & Scope::DeclScope) == 0) || 672 (S->getEntity() && 673 ((DeclContext *)S->getEntity())->isTransparentContext()) || 674 (S->isClassScope() && !getLangOptions().CPlusPlus)) 675 S = S->getParent(); 676 return S; 677} 678 679void Sema::InitBuiltinVaListType() { 680 if (!Context.getBuiltinVaListType().isNull()) 681 return; 682 683 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 684 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 685 LookupOrdinaryName, ForRedeclaration); 686 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 687 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 688} 689 690/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 691/// file scope. lazily create a decl for it. ForRedeclaration is true 692/// if we're creating this built-in in anticipation of redeclaring the 693/// built-in. 694NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 695 Scope *S, bool ForRedeclaration, 696 SourceLocation Loc) { 697 Builtin::ID BID = (Builtin::ID)bid; 698 699 if (Context.BuiltinInfo.hasVAListUse(BID)) 700 InitBuiltinVaListType(); 701 702 ASTContext::GetBuiltinTypeError Error; 703 QualType R = Context.GetBuiltinType(BID, Error); 704 switch (Error) { 705 case ASTContext::GE_None: 706 // Okay 707 break; 708 709 case ASTContext::GE_Missing_stdio: 710 if (ForRedeclaration) 711 Diag(Loc, diag::err_implicit_decl_requires_stdio) 712 << Context.BuiltinInfo.GetName(BID); 713 return 0; 714 715 case ASTContext::GE_Missing_setjmp: 716 if (ForRedeclaration) 717 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 718 << Context.BuiltinInfo.GetName(BID); 719 return 0; 720 } 721 722 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 723 Diag(Loc, diag::ext_implicit_lib_function_decl) 724 << Context.BuiltinInfo.GetName(BID) 725 << R; 726 if (Context.BuiltinInfo.getHeaderName(BID) && 727 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 728 != Diagnostic::Ignored) 729 Diag(Loc, diag::note_please_include_header) 730 << Context.BuiltinInfo.getHeaderName(BID) 731 << Context.BuiltinInfo.GetName(BID); 732 } 733 734 FunctionDecl *New = FunctionDecl::Create(Context, 735 Context.getTranslationUnitDecl(), 736 Loc, II, R, /*TInfo=*/0, 737 FunctionDecl::Extern, 738 FunctionDecl::None, false, 739 /*hasPrototype=*/true); 740 New->setImplicit(); 741 742 // Create Decl objects for each parameter, adding them to the 743 // FunctionDecl. 744 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 745 llvm::SmallVector<ParmVarDecl*, 16> Params; 746 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 747 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 748 FT->getArgType(i), /*TInfo=*/0, 749 VarDecl::None, VarDecl::None, 0)); 750 New->setParams(Params.data(), Params.size()); 751 } 752 753 AddKnownFunctionAttributes(New); 754 755 // TUScope is the translation-unit scope to insert this function into. 756 // FIXME: This is hideous. We need to teach PushOnScopeChains to 757 // relate Scopes to DeclContexts, and probably eliminate CurContext 758 // entirely, but we're not there yet. 759 DeclContext *SavedContext = CurContext; 760 CurContext = Context.getTranslationUnitDecl(); 761 PushOnScopeChains(New, TUScope); 762 CurContext = SavedContext; 763 return New; 764} 765 766/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 767/// same name and scope as a previous declaration 'Old'. Figure out 768/// how to resolve this situation, merging decls or emitting 769/// diagnostics as appropriate. If there was an error, set New to be invalid. 770/// 771void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 772 // If the new decl is known invalid already, don't bother doing any 773 // merging checks. 774 if (New->isInvalidDecl()) return; 775 776 // Allow multiple definitions for ObjC built-in typedefs. 777 // FIXME: Verify the underlying types are equivalent! 778 if (getLangOptions().ObjC1) { 779 const IdentifierInfo *TypeID = New->getIdentifier(); 780 switch (TypeID->getLength()) { 781 default: break; 782 case 2: 783 if (!TypeID->isStr("id")) 784 break; 785 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 786 // Install the built-in type for 'id', ignoring the current definition. 787 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 788 return; 789 case 5: 790 if (!TypeID->isStr("Class")) 791 break; 792 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 793 // Install the built-in type for 'Class', ignoring the current definition. 794 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 795 return; 796 case 3: 797 if (!TypeID->isStr("SEL")) 798 break; 799 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 800 // Install the built-in type for 'SEL', ignoring the current definition. 801 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 802 return; 803 case 8: 804 if (!TypeID->isStr("Protocol")) 805 break; 806 Context.setObjCProtoType(New->getUnderlyingType()); 807 return; 808 } 809 // Fall through - the typedef name was not a builtin type. 810 } 811 812 // Verify the old decl was also a type. 813 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 814 if (!Old) { 815 Diag(New->getLocation(), diag::err_redefinition_different_kind) 816 << New->getDeclName(); 817 818 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 819 if (OldD->getLocation().isValid()) 820 Diag(OldD->getLocation(), diag::note_previous_definition); 821 822 return New->setInvalidDecl(); 823 } 824 825 // If the old declaration is invalid, just give up here. 826 if (Old->isInvalidDecl()) 827 return New->setInvalidDecl(); 828 829 // Determine the "old" type we'll use for checking and diagnostics. 830 QualType OldType; 831 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 832 OldType = OldTypedef->getUnderlyingType(); 833 else 834 OldType = Context.getTypeDeclType(Old); 835 836 // If the typedef types are not identical, reject them in all languages and 837 // with any extensions enabled. 838 839 if (OldType != New->getUnderlyingType() && 840 Context.getCanonicalType(OldType) != 841 Context.getCanonicalType(New->getUnderlyingType())) { 842 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 843 << New->getUnderlyingType() << OldType; 844 if (Old->getLocation().isValid()) 845 Diag(Old->getLocation(), diag::note_previous_definition); 846 return New->setInvalidDecl(); 847 } 848 849 // The types match. Link up the redeclaration chain if the old 850 // declaration was a typedef. 851 // FIXME: this is a potential source of wierdness if the type 852 // spellings don't match exactly. 853 if (isa<TypedefDecl>(Old)) 854 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 855 856 if (getLangOptions().Microsoft) 857 return; 858 859 if (getLangOptions().CPlusPlus) { 860 // C++ [dcl.typedef]p2: 861 // In a given non-class scope, a typedef specifier can be used to 862 // redefine the name of any type declared in that scope to refer 863 // to the type to which it already refers. 864 if (!isa<CXXRecordDecl>(CurContext)) 865 return; 866 867 // C++0x [dcl.typedef]p4: 868 // In a given class scope, a typedef specifier can be used to redefine 869 // any class-name declared in that scope that is not also a typedef-name 870 // to refer to the type to which it already refers. 871 // 872 // This wording came in via DR424, which was a correction to the 873 // wording in DR56, which accidentally banned code like: 874 // 875 // struct S { 876 // typedef struct A { } A; 877 // }; 878 // 879 // in the C++03 standard. We implement the C++0x semantics, which 880 // allow the above but disallow 881 // 882 // struct S { 883 // typedef int I; 884 // typedef int I; 885 // }; 886 // 887 // since that was the intent of DR56. 888 if (!isa<TypedefDecl >(Old)) 889 return; 890 891 Diag(New->getLocation(), diag::err_redefinition) 892 << New->getDeclName(); 893 Diag(Old->getLocation(), diag::note_previous_definition); 894 return New->setInvalidDecl(); 895 } 896 897 // If we have a redefinition of a typedef in C, emit a warning. This warning 898 // is normally mapped to an error, but can be controlled with 899 // -Wtypedef-redefinition. If either the original or the redefinition is 900 // in a system header, don't emit this for compatibility with GCC. 901 if (getDiagnostics().getSuppressSystemWarnings() && 902 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 903 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 904 return; 905 906 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 907 << New->getDeclName(); 908 Diag(Old->getLocation(), diag::note_previous_definition); 909 return; 910} 911 912/// DeclhasAttr - returns true if decl Declaration already has the target 913/// attribute. 914static bool 915DeclHasAttr(const Decl *decl, const Attr *target) { 916 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 917 if (attr->getKind() == target->getKind()) 918 return true; 919 920 return false; 921} 922 923/// MergeAttributes - append attributes from the Old decl to the New one. 924static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 925 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 926 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 927 Attr *NewAttr = attr->clone(C); 928 NewAttr->setInherited(true); 929 New->addAttr(NewAttr); 930 } 931 } 932} 933 934namespace { 935 936/// Used in MergeFunctionDecl to keep track of function parameters in 937/// C. 938struct GNUCompatibleParamWarning { 939 ParmVarDecl *OldParm; 940 ParmVarDecl *NewParm; 941 QualType PromotedType; 942}; 943 944} 945 946/// getSpecialMember - get the special member enum for a method. 947Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 948 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 949 if (Ctor->isCopyConstructor()) 950 return Sema::CXXCopyConstructor; 951 952 return Sema::CXXConstructor; 953 } 954 955 if (isa<CXXDestructorDecl>(MD)) 956 return Sema::CXXDestructor; 957 958 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 959 return Sema::CXXCopyAssignment; 960} 961 962/// canRedefineFunction - checks if a function can be redefined. Currently, 963/// only extern inline functions can be redefined, and even then only in 964/// GNU89 mode. 965static bool canRedefineFunction(const FunctionDecl *FD, 966 const LangOptions& LangOpts) { 967 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 968 FD->isInlineSpecified() && 969 FD->getStorageClass() == FunctionDecl::Extern); 970} 971 972/// MergeFunctionDecl - We just parsed a function 'New' from 973/// declarator D which has the same name and scope as a previous 974/// declaration 'Old'. Figure out how to resolve this situation, 975/// merging decls or emitting diagnostics as appropriate. 976/// 977/// In C++, New and Old must be declarations that are not 978/// overloaded. Use IsOverload to determine whether New and Old are 979/// overloaded, and to select the Old declaration that New should be 980/// merged with. 981/// 982/// Returns true if there was an error, false otherwise. 983bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 984 // Verify the old decl was also a function. 985 FunctionDecl *Old = 0; 986 if (FunctionTemplateDecl *OldFunctionTemplate 987 = dyn_cast<FunctionTemplateDecl>(OldD)) 988 Old = OldFunctionTemplate->getTemplatedDecl(); 989 else 990 Old = dyn_cast<FunctionDecl>(OldD); 991 if (!Old) { 992 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 993 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 994 Diag(Shadow->getTargetDecl()->getLocation(), 995 diag::note_using_decl_target); 996 Diag(Shadow->getUsingDecl()->getLocation(), 997 diag::note_using_decl) << 0; 998 return true; 999 } 1000 1001 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1002 << New->getDeclName(); 1003 Diag(OldD->getLocation(), diag::note_previous_definition); 1004 return true; 1005 } 1006 1007 // Determine whether the previous declaration was a definition, 1008 // implicit declaration, or a declaration. 1009 diag::kind PrevDiag; 1010 if (Old->isThisDeclarationADefinition()) 1011 PrevDiag = diag::note_previous_definition; 1012 else if (Old->isImplicit()) 1013 PrevDiag = diag::note_previous_implicit_declaration; 1014 else 1015 PrevDiag = diag::note_previous_declaration; 1016 1017 QualType OldQType = Context.getCanonicalType(Old->getType()); 1018 QualType NewQType = Context.getCanonicalType(New->getType()); 1019 1020 // Don't complain about this if we're in GNU89 mode and the old function 1021 // is an extern inline function. 1022 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1023 New->getStorageClass() == FunctionDecl::Static && 1024 Old->getStorageClass() != FunctionDecl::Static && 1025 !canRedefineFunction(Old, getLangOptions())) { 1026 Diag(New->getLocation(), diag::err_static_non_static) 1027 << New; 1028 Diag(Old->getLocation(), PrevDiag); 1029 return true; 1030 } 1031 1032 // If a function is first declared with a calling convention, but is 1033 // later declared or defined without one, the second decl assumes the 1034 // calling convention of the first. 1035 // 1036 // For the new decl, we have to look at the NON-canonical type to tell the 1037 // difference between a function that really doesn't have a calling 1038 // convention and one that is declared cdecl. That's because in 1039 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1040 // because it is the default calling convention. 1041 // 1042 // Note also that we DO NOT return at this point, because we still have 1043 // other tests to run. 1044 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1045 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1046 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1047 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1048 if (OldTypeInfo.getCC() != CC_Default && 1049 NewTypeInfo.getCC() == CC_Default) { 1050 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1051 New->setType(NewQType); 1052 NewQType = Context.getCanonicalType(NewQType); 1053 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1054 NewTypeInfo.getCC())) { 1055 // Calling conventions really aren't compatible, so complain. 1056 Diag(New->getLocation(), diag::err_cconv_change) 1057 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1058 << (OldTypeInfo.getCC() == CC_Default) 1059 << (OldTypeInfo.getCC() == CC_Default ? "" : 1060 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1061 Diag(Old->getLocation(), diag::note_previous_declaration); 1062 return true; 1063 } 1064 1065 // FIXME: diagnose the other way around? 1066 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1067 NewQType = Context.getNoReturnType(NewQType); 1068 New->setType(NewQType); 1069 assert(NewQType.isCanonical()); 1070 } 1071 1072 // Merge regparm attribute. 1073 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1074 if (NewType->getRegParmType()) { 1075 Diag(New->getLocation(), diag::err_regparm_mismatch) 1076 << NewType->getRegParmType() 1077 << OldType->getRegParmType(); 1078 Diag(Old->getLocation(), diag::note_previous_declaration); 1079 return true; 1080 } 1081 1082 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1083 New->setType(NewQType); 1084 assert(NewQType.isCanonical()); 1085 } 1086 1087 if (getLangOptions().CPlusPlus) { 1088 // (C++98 13.1p2): 1089 // Certain function declarations cannot be overloaded: 1090 // -- Function declarations that differ only in the return type 1091 // cannot be overloaded. 1092 QualType OldReturnType 1093 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1094 QualType NewReturnType 1095 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1096 QualType ResQT; 1097 if (OldReturnType != NewReturnType) { 1098 if (NewReturnType->isObjCObjectPointerType() 1099 && OldReturnType->isObjCObjectPointerType()) 1100 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1101 if (ResQT.isNull()) { 1102 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1103 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1104 return true; 1105 } 1106 else 1107 NewQType = ResQT; 1108 } 1109 1110 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1111 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1112 if (OldMethod && NewMethod) { 1113 // Preserve triviality. 1114 NewMethod->setTrivial(OldMethod->isTrivial()); 1115 1116 bool isFriend = NewMethod->getFriendObjectKind(); 1117 1118 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1119 // -- Member function declarations with the same name and the 1120 // same parameter types cannot be overloaded if any of them 1121 // is a static member function declaration. 1122 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1123 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1124 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1125 return true; 1126 } 1127 1128 // C++ [class.mem]p1: 1129 // [...] A member shall not be declared twice in the 1130 // member-specification, except that a nested class or member 1131 // class template can be declared and then later defined. 1132 unsigned NewDiag; 1133 if (isa<CXXConstructorDecl>(OldMethod)) 1134 NewDiag = diag::err_constructor_redeclared; 1135 else if (isa<CXXDestructorDecl>(NewMethod)) 1136 NewDiag = diag::err_destructor_redeclared; 1137 else if (isa<CXXConversionDecl>(NewMethod)) 1138 NewDiag = diag::err_conv_function_redeclared; 1139 else 1140 NewDiag = diag::err_member_redeclared; 1141 1142 Diag(New->getLocation(), NewDiag); 1143 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1144 1145 // Complain if this is an explicit declaration of a special 1146 // member that was initially declared implicitly. 1147 // 1148 // As an exception, it's okay to befriend such methods in order 1149 // to permit the implicit constructor/destructor/operator calls. 1150 } else if (OldMethod->isImplicit()) { 1151 if (isFriend) { 1152 NewMethod->setImplicit(); 1153 } else { 1154 Diag(NewMethod->getLocation(), 1155 diag::err_definition_of_implicitly_declared_member) 1156 << New << getSpecialMember(OldMethod); 1157 return true; 1158 } 1159 } 1160 } 1161 1162 // (C++98 8.3.5p3): 1163 // All declarations for a function shall agree exactly in both the 1164 // return type and the parameter-type-list. 1165 // attributes should be ignored when comparing. 1166 if (Context.getNoReturnType(OldQType, false) == 1167 Context.getNoReturnType(NewQType, false)) 1168 return MergeCompatibleFunctionDecls(New, Old); 1169 1170 // Fall through for conflicting redeclarations and redefinitions. 1171 } 1172 1173 // C: Function types need to be compatible, not identical. This handles 1174 // duplicate function decls like "void f(int); void f(enum X);" properly. 1175 if (!getLangOptions().CPlusPlus && 1176 Context.typesAreCompatible(OldQType, NewQType)) { 1177 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1178 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1179 const FunctionProtoType *OldProto = 0; 1180 if (isa<FunctionNoProtoType>(NewFuncType) && 1181 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1182 // The old declaration provided a function prototype, but the 1183 // new declaration does not. Merge in the prototype. 1184 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1185 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1186 OldProto->arg_type_end()); 1187 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1188 ParamTypes.data(), ParamTypes.size(), 1189 OldProto->isVariadic(), 1190 OldProto->getTypeQuals(), 1191 false, false, 0, 0, 1192 OldProto->getExtInfo()); 1193 New->setType(NewQType); 1194 New->setHasInheritedPrototype(); 1195 1196 // Synthesize a parameter for each argument type. 1197 llvm::SmallVector<ParmVarDecl*, 16> Params; 1198 for (FunctionProtoType::arg_type_iterator 1199 ParamType = OldProto->arg_type_begin(), 1200 ParamEnd = OldProto->arg_type_end(); 1201 ParamType != ParamEnd; ++ParamType) { 1202 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1203 SourceLocation(), 0, 1204 *ParamType, /*TInfo=*/0, 1205 VarDecl::None, VarDecl::None, 1206 0); 1207 Param->setImplicit(); 1208 Params.push_back(Param); 1209 } 1210 1211 New->setParams(Params.data(), Params.size()); 1212 } 1213 1214 return MergeCompatibleFunctionDecls(New, Old); 1215 } 1216 1217 // GNU C permits a K&R definition to follow a prototype declaration 1218 // if the declared types of the parameters in the K&R definition 1219 // match the types in the prototype declaration, even when the 1220 // promoted types of the parameters from the K&R definition differ 1221 // from the types in the prototype. GCC then keeps the types from 1222 // the prototype. 1223 // 1224 // If a variadic prototype is followed by a non-variadic K&R definition, 1225 // the K&R definition becomes variadic. This is sort of an edge case, but 1226 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1227 // C99 6.9.1p8. 1228 if (!getLangOptions().CPlusPlus && 1229 Old->hasPrototype() && !New->hasPrototype() && 1230 New->getType()->getAs<FunctionProtoType>() && 1231 Old->getNumParams() == New->getNumParams()) { 1232 llvm::SmallVector<QualType, 16> ArgTypes; 1233 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1234 const FunctionProtoType *OldProto 1235 = Old->getType()->getAs<FunctionProtoType>(); 1236 const FunctionProtoType *NewProto 1237 = New->getType()->getAs<FunctionProtoType>(); 1238 1239 // Determine whether this is the GNU C extension. 1240 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1241 NewProto->getResultType()); 1242 bool LooseCompatible = !MergedReturn.isNull(); 1243 for (unsigned Idx = 0, End = Old->getNumParams(); 1244 LooseCompatible && Idx != End; ++Idx) { 1245 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1246 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1247 if (Context.typesAreCompatible(OldParm->getType(), 1248 NewProto->getArgType(Idx))) { 1249 ArgTypes.push_back(NewParm->getType()); 1250 } else if (Context.typesAreCompatible(OldParm->getType(), 1251 NewParm->getType(), 1252 /*CompareUnqualified=*/true)) { 1253 GNUCompatibleParamWarning Warn 1254 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1255 Warnings.push_back(Warn); 1256 ArgTypes.push_back(NewParm->getType()); 1257 } else 1258 LooseCompatible = false; 1259 } 1260 1261 if (LooseCompatible) { 1262 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1263 Diag(Warnings[Warn].NewParm->getLocation(), 1264 diag::ext_param_promoted_not_compatible_with_prototype) 1265 << Warnings[Warn].PromotedType 1266 << Warnings[Warn].OldParm->getType(); 1267 if (Warnings[Warn].OldParm->getLocation().isValid()) 1268 Diag(Warnings[Warn].OldParm->getLocation(), 1269 diag::note_previous_declaration); 1270 } 1271 1272 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1273 ArgTypes.size(), 1274 OldProto->isVariadic(), 0, 1275 false, false, 0, 0, 1276 OldProto->getExtInfo())); 1277 return MergeCompatibleFunctionDecls(New, Old); 1278 } 1279 1280 // Fall through to diagnose conflicting types. 1281 } 1282 1283 // A function that has already been declared has been redeclared or defined 1284 // with a different type- show appropriate diagnostic 1285 if (unsigned BuiltinID = Old->getBuiltinID()) { 1286 // The user has declared a builtin function with an incompatible 1287 // signature. 1288 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1289 // The function the user is redeclaring is a library-defined 1290 // function like 'malloc' or 'printf'. Warn about the 1291 // redeclaration, then pretend that we don't know about this 1292 // library built-in. 1293 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1294 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1295 << Old << Old->getType(); 1296 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1297 Old->setInvalidDecl(); 1298 return false; 1299 } 1300 1301 PrevDiag = diag::note_previous_builtin_declaration; 1302 } 1303 1304 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1305 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1306 return true; 1307} 1308 1309/// \brief Completes the merge of two function declarations that are 1310/// known to be compatible. 1311/// 1312/// This routine handles the merging of attributes and other 1313/// properties of function declarations form the old declaration to 1314/// the new declaration, once we know that New is in fact a 1315/// redeclaration of Old. 1316/// 1317/// \returns false 1318bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1319 // Merge the attributes 1320 MergeAttributes(New, Old, Context); 1321 1322 // Merge the storage class. 1323 if (Old->getStorageClass() != FunctionDecl::Extern && 1324 Old->getStorageClass() != FunctionDecl::None) 1325 New->setStorageClass(Old->getStorageClass()); 1326 1327 // Merge "pure" flag. 1328 if (Old->isPure()) 1329 New->setPure(); 1330 1331 // Merge the "deleted" flag. 1332 if (Old->isDeleted()) 1333 New->setDeleted(); 1334 1335 if (getLangOptions().CPlusPlus) 1336 return MergeCXXFunctionDecl(New, Old); 1337 1338 return false; 1339} 1340 1341/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1342/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1343/// situation, merging decls or emitting diagnostics as appropriate. 1344/// 1345/// Tentative definition rules (C99 6.9.2p2) are checked by 1346/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1347/// definitions here, since the initializer hasn't been attached. 1348/// 1349void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1350 // If the new decl is already invalid, don't do any other checking. 1351 if (New->isInvalidDecl()) 1352 return; 1353 1354 // Verify the old decl was also a variable. 1355 VarDecl *Old = 0; 1356 if (!Previous.isSingleResult() || 1357 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1358 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1359 << New->getDeclName(); 1360 Diag(Previous.getRepresentativeDecl()->getLocation(), 1361 diag::note_previous_definition); 1362 return New->setInvalidDecl(); 1363 } 1364 1365 MergeAttributes(New, Old, Context); 1366 1367 // Merge the types 1368 QualType MergedT; 1369 if (getLangOptions().CPlusPlus) { 1370 if (Context.hasSameType(New->getType(), Old->getType())) 1371 MergedT = New->getType(); 1372 // C++ [basic.link]p10: 1373 // [...] the types specified by all declarations referring to a given 1374 // object or function shall be identical, except that declarations for an 1375 // array object can specify array types that differ by the presence or 1376 // absence of a major array bound (8.3.4). 1377 else if (Old->getType()->isIncompleteArrayType() && 1378 New->getType()->isArrayType()) { 1379 CanQual<ArrayType> OldArray 1380 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1381 CanQual<ArrayType> NewArray 1382 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1383 if (OldArray->getElementType() == NewArray->getElementType()) 1384 MergedT = New->getType(); 1385 } else if (Old->getType()->isArrayType() && 1386 New->getType()->isIncompleteArrayType()) { 1387 CanQual<ArrayType> OldArray 1388 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1389 CanQual<ArrayType> NewArray 1390 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1391 if (OldArray->getElementType() == NewArray->getElementType()) 1392 MergedT = Old->getType(); 1393 } else if (New->getType()->isObjCObjectPointerType() 1394 && Old->getType()->isObjCObjectPointerType()) { 1395 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1396 } 1397 } else { 1398 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1399 } 1400 if (MergedT.isNull()) { 1401 Diag(New->getLocation(), diag::err_redefinition_different_type) 1402 << New->getDeclName(); 1403 Diag(Old->getLocation(), diag::note_previous_definition); 1404 return New->setInvalidDecl(); 1405 } 1406 New->setType(MergedT); 1407 1408 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1409 if (New->getStorageClass() == VarDecl::Static && 1410 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1411 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1412 Diag(Old->getLocation(), diag::note_previous_definition); 1413 return New->setInvalidDecl(); 1414 } 1415 // C99 6.2.2p4: 1416 // For an identifier declared with the storage-class specifier 1417 // extern in a scope in which a prior declaration of that 1418 // identifier is visible,23) if the prior declaration specifies 1419 // internal or external linkage, the linkage of the identifier at 1420 // the later declaration is the same as the linkage specified at 1421 // the prior declaration. If no prior declaration is visible, or 1422 // if the prior declaration specifies no linkage, then the 1423 // identifier has external linkage. 1424 if (New->hasExternalStorage() && Old->hasLinkage()) 1425 /* Okay */; 1426 else if (New->getStorageClass() != VarDecl::Static && 1427 Old->getStorageClass() == VarDecl::Static) { 1428 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1429 Diag(Old->getLocation(), diag::note_previous_definition); 1430 return New->setInvalidDecl(); 1431 } 1432 1433 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1434 1435 // FIXME: The test for external storage here seems wrong? We still 1436 // need to check for mismatches. 1437 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1438 // Don't complain about out-of-line definitions of static members. 1439 !(Old->getLexicalDeclContext()->isRecord() && 1440 !New->getLexicalDeclContext()->isRecord())) { 1441 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1442 Diag(Old->getLocation(), diag::note_previous_definition); 1443 return New->setInvalidDecl(); 1444 } 1445 1446 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1447 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1448 Diag(Old->getLocation(), diag::note_previous_definition); 1449 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1450 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1451 Diag(Old->getLocation(), diag::note_previous_definition); 1452 } 1453 1454 // C++ doesn't have tentative definitions, so go right ahead and check here. 1455 const VarDecl *Def; 1456 if (getLangOptions().CPlusPlus && 1457 New->isThisDeclarationADefinition() == VarDecl::Definition && 1458 (Def = Old->getDefinition())) { 1459 Diag(New->getLocation(), diag::err_redefinition) 1460 << New->getDeclName(); 1461 Diag(Def->getLocation(), diag::note_previous_definition); 1462 New->setInvalidDecl(); 1463 return; 1464 } 1465 // c99 6.2.2 P4. 1466 // For an identifier declared with the storage-class specifier extern in a 1467 // scope in which a prior declaration of that identifier is visible, if 1468 // the prior declaration specifies internal or external linkage, the linkage 1469 // of the identifier at the later declaration is the same as the linkage 1470 // specified at the prior declaration. 1471 // FIXME. revisit this code. 1472 if (New->hasExternalStorage() && 1473 Old->getLinkage() == InternalLinkage && 1474 New->getDeclContext() == Old->getDeclContext()) 1475 New->setStorageClass(Old->getStorageClass()); 1476 1477 // Keep a chain of previous declarations. 1478 New->setPreviousDeclaration(Old); 1479 1480 // Inherit access appropriately. 1481 New->setAccess(Old->getAccess()); 1482} 1483 1484/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1485/// no declarator (e.g. "struct foo;") is parsed. 1486Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1487 DeclSpec &DS) { 1488 // FIXME: Error on auto/register at file scope 1489 // FIXME: Error on inline/virtual/explicit 1490 // FIXME: Warn on useless __thread 1491 // FIXME: Warn on useless const/volatile 1492 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1493 // FIXME: Warn on useless attributes 1494 Decl *TagD = 0; 1495 TagDecl *Tag = 0; 1496 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1497 DS.getTypeSpecType() == DeclSpec::TST_struct || 1498 DS.getTypeSpecType() == DeclSpec::TST_union || 1499 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1500 TagD = static_cast<Decl *>(DS.getTypeRep()); 1501 1502 if (!TagD) // We probably had an error 1503 return DeclPtrTy(); 1504 1505 // Note that the above type specs guarantee that the 1506 // type rep is a Decl, whereas in many of the others 1507 // it's a Type. 1508 Tag = dyn_cast<TagDecl>(TagD); 1509 } 1510 1511 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1512 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1513 // or incomplete types shall not be restrict-qualified." 1514 if (TypeQuals & DeclSpec::TQ_restrict) 1515 Diag(DS.getRestrictSpecLoc(), 1516 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1517 << DS.getSourceRange(); 1518 } 1519 1520 if (DS.isFriendSpecified()) { 1521 // If we're dealing with a class template decl, assume that the 1522 // template routines are handling it. 1523 if (TagD && isa<ClassTemplateDecl>(TagD)) 1524 return DeclPtrTy(); 1525 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1526 } 1527 1528 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1529 // If there are attributes in the DeclSpec, apply them to the record. 1530 if (const AttributeList *AL = DS.getAttributes()) 1531 ProcessDeclAttributeList(S, Record, AL); 1532 1533 if (!Record->getDeclName() && Record->isDefinition() && 1534 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1535 if (getLangOptions().CPlusPlus || 1536 Record->getDeclContext()->isRecord()) 1537 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1538 1539 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1540 << DS.getSourceRange(); 1541 } 1542 1543 // Microsoft allows unnamed struct/union fields. Don't complain 1544 // about them. 1545 // FIXME: Should we support Microsoft's extensions in this area? 1546 if (Record->getDeclName() && getLangOptions().Microsoft) 1547 return DeclPtrTy::make(Tag); 1548 } 1549 1550 if (getLangOptions().CPlusPlus && 1551 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1552 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1553 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1554 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1555 Diag(Enum->getLocation(), diag::ext_no_declarators) 1556 << DS.getSourceRange(); 1557 1558 if (!DS.isMissingDeclaratorOk() && 1559 DS.getTypeSpecType() != DeclSpec::TST_error) { 1560 // Warn about typedefs of enums without names, since this is an 1561 // extension in both Microsoft and GNU. 1562 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1563 Tag && isa<EnumDecl>(Tag)) { 1564 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1565 << DS.getSourceRange(); 1566 return DeclPtrTy::make(Tag); 1567 } 1568 1569 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1570 << DS.getSourceRange(); 1571 } 1572 1573 return DeclPtrTy::make(TagD); 1574} 1575 1576/// We are trying to inject an anonymous member into the given scope; 1577/// check if there's an existing declaration that can't be overloaded. 1578/// 1579/// \return true if this is a forbidden redeclaration 1580static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1581 Scope *S, 1582 DeclContext *Owner, 1583 DeclarationName Name, 1584 SourceLocation NameLoc, 1585 unsigned diagnostic) { 1586 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1587 Sema::ForRedeclaration); 1588 if (!SemaRef.LookupName(R, S)) return false; 1589 1590 if (R.getAsSingle<TagDecl>()) 1591 return false; 1592 1593 // Pick a representative declaration. 1594 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1595 if (PrevDecl && Owner->isRecord()) { 1596 RecordDecl *Record = cast<RecordDecl>(Owner); 1597 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1598 return false; 1599 } 1600 1601 SemaRef.Diag(NameLoc, diagnostic) << Name; 1602 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1603 1604 return true; 1605} 1606 1607/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1608/// anonymous struct or union AnonRecord into the owning context Owner 1609/// and scope S. This routine will be invoked just after we realize 1610/// that an unnamed union or struct is actually an anonymous union or 1611/// struct, e.g., 1612/// 1613/// @code 1614/// union { 1615/// int i; 1616/// float f; 1617/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1618/// // f into the surrounding scope.x 1619/// @endcode 1620/// 1621/// This routine is recursive, injecting the names of nested anonymous 1622/// structs/unions into the owning context and scope as well. 1623static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1624 DeclContext *Owner, 1625 RecordDecl *AnonRecord, 1626 AccessSpecifier AS) { 1627 unsigned diagKind 1628 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1629 : diag::err_anonymous_struct_member_redecl; 1630 1631 bool Invalid = false; 1632 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1633 FEnd = AnonRecord->field_end(); 1634 F != FEnd; ++F) { 1635 if ((*F)->getDeclName()) { 1636 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1637 (*F)->getLocation(), diagKind)) { 1638 // C++ [class.union]p2: 1639 // The names of the members of an anonymous union shall be 1640 // distinct from the names of any other entity in the 1641 // scope in which the anonymous union is declared. 1642 Invalid = true; 1643 } else { 1644 // C++ [class.union]p2: 1645 // For the purpose of name lookup, after the anonymous union 1646 // definition, the members of the anonymous union are 1647 // considered to have been defined in the scope in which the 1648 // anonymous union is declared. 1649 Owner->makeDeclVisibleInContext(*F); 1650 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1651 SemaRef.IdResolver.AddDecl(*F); 1652 1653 // That includes picking up the appropriate access specifier. 1654 if (AS != AS_none) (*F)->setAccess(AS); 1655 } 1656 } else if (const RecordType *InnerRecordType 1657 = (*F)->getType()->getAs<RecordType>()) { 1658 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1659 if (InnerRecord->isAnonymousStructOrUnion()) 1660 Invalid = Invalid || 1661 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1662 InnerRecord, AS); 1663 } 1664 } 1665 1666 return Invalid; 1667} 1668 1669/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1670/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1671/// illegal input values are mapped to VarDecl::None. 1672static VarDecl::StorageClass 1673StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1674 switch (StorageClassSpec) { 1675 case DeclSpec::SCS_unspecified: return VarDecl::None; 1676 case DeclSpec::SCS_extern: return VarDecl::Extern; 1677 case DeclSpec::SCS_static: return VarDecl::Static; 1678 case DeclSpec::SCS_auto: return VarDecl::Auto; 1679 case DeclSpec::SCS_register: return VarDecl::Register; 1680 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1681 // Illegal SCSs map to None: error reporting is up to the caller. 1682 case DeclSpec::SCS_mutable: // Fall through. 1683 case DeclSpec::SCS_typedef: return VarDecl::None; 1684 } 1685 llvm_unreachable("unknown storage class specifier"); 1686} 1687 1688/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1689/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1690/// illegal input values are mapped to FunctionDecl::None. 1691static FunctionDecl::StorageClass 1692StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1693 switch (StorageClassSpec) { 1694 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1695 case DeclSpec::SCS_extern: return FunctionDecl::Extern; 1696 case DeclSpec::SCS_static: return FunctionDecl::Static; 1697 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1698 // Illegal SCSs map to None: error reporting is up to the caller. 1699 case DeclSpec::SCS_auto: // Fall through. 1700 case DeclSpec::SCS_mutable: // Fall through. 1701 case DeclSpec::SCS_register: // Fall through. 1702 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1703 } 1704 llvm_unreachable("unknown storage class specifier"); 1705} 1706 1707/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1708/// anonymous structure or union. Anonymous unions are a C++ feature 1709/// (C++ [class.union]) and a GNU C extension; anonymous structures 1710/// are a GNU C and GNU C++ extension. 1711Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1712 AccessSpecifier AS, 1713 RecordDecl *Record) { 1714 DeclContext *Owner = Record->getDeclContext(); 1715 1716 // Diagnose whether this anonymous struct/union is an extension. 1717 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1718 Diag(Record->getLocation(), diag::ext_anonymous_union); 1719 else if (!Record->isUnion()) 1720 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1721 1722 // C and C++ require different kinds of checks for anonymous 1723 // structs/unions. 1724 bool Invalid = false; 1725 if (getLangOptions().CPlusPlus) { 1726 const char* PrevSpec = 0; 1727 unsigned DiagID; 1728 // C++ [class.union]p3: 1729 // Anonymous unions declared in a named namespace or in the 1730 // global namespace shall be declared static. 1731 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1732 (isa<TranslationUnitDecl>(Owner) || 1733 (isa<NamespaceDecl>(Owner) && 1734 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1735 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1736 Invalid = true; 1737 1738 // Recover by adding 'static'. 1739 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1740 PrevSpec, DiagID); 1741 } 1742 // C++ [class.union]p3: 1743 // A storage class is not allowed in a declaration of an 1744 // anonymous union in a class scope. 1745 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1746 isa<RecordDecl>(Owner)) { 1747 Diag(DS.getStorageClassSpecLoc(), 1748 diag::err_anonymous_union_with_storage_spec); 1749 Invalid = true; 1750 1751 // Recover by removing the storage specifier. 1752 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1753 PrevSpec, DiagID); 1754 } 1755 1756 // C++ [class.union]p2: 1757 // The member-specification of an anonymous union shall only 1758 // define non-static data members. [Note: nested types and 1759 // functions cannot be declared within an anonymous union. ] 1760 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1761 MemEnd = Record->decls_end(); 1762 Mem != MemEnd; ++Mem) { 1763 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1764 // C++ [class.union]p3: 1765 // An anonymous union shall not have private or protected 1766 // members (clause 11). 1767 assert(FD->getAccess() != AS_none); 1768 if (FD->getAccess() != AS_public) { 1769 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1770 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1771 Invalid = true; 1772 } 1773 } else if ((*Mem)->isImplicit()) { 1774 // Any implicit members are fine. 1775 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1776 // This is a type that showed up in an 1777 // elaborated-type-specifier inside the anonymous struct or 1778 // union, but which actually declares a type outside of the 1779 // anonymous struct or union. It's okay. 1780 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1781 if (!MemRecord->isAnonymousStructOrUnion() && 1782 MemRecord->getDeclName()) { 1783 // This is a nested type declaration. 1784 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1785 << (int)Record->isUnion(); 1786 Invalid = true; 1787 } 1788 } else if (isa<AccessSpecDecl>(*Mem)) { 1789 // Any access specifier is fine. 1790 } else { 1791 // We have something that isn't a non-static data 1792 // member. Complain about it. 1793 unsigned DK = diag::err_anonymous_record_bad_member; 1794 if (isa<TypeDecl>(*Mem)) 1795 DK = diag::err_anonymous_record_with_type; 1796 else if (isa<FunctionDecl>(*Mem)) 1797 DK = diag::err_anonymous_record_with_function; 1798 else if (isa<VarDecl>(*Mem)) 1799 DK = diag::err_anonymous_record_with_static; 1800 Diag((*Mem)->getLocation(), DK) 1801 << (int)Record->isUnion(); 1802 Invalid = true; 1803 } 1804 } 1805 } 1806 1807 if (!Record->isUnion() && !Owner->isRecord()) { 1808 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1809 << (int)getLangOptions().CPlusPlus; 1810 Invalid = true; 1811 } 1812 1813 // Mock up a declarator. 1814 Declarator Dc(DS, Declarator::TypeNameContext); 1815 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1816 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1817 1818 // Create a declaration for this anonymous struct/union. 1819 NamedDecl *Anon = 0; 1820 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1821 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1822 /*IdentifierInfo=*/0, 1823 Context.getTypeDeclType(Record), 1824 TInfo, 1825 /*BitWidth=*/0, /*Mutable=*/false); 1826 Anon->setAccess(AS); 1827 if (getLangOptions().CPlusPlus) { 1828 FieldCollector->Add(cast<FieldDecl>(Anon)); 1829 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1830 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1831 } 1832 } else { 1833 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1834 assert(SCSpec != DeclSpec::SCS_typedef && 1835 "Parser allowed 'typedef' as storage class VarDecl."); 1836 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1837 if (SCSpec == DeclSpec::SCS_mutable) { 1838 // mutable can only appear on non-static class members, so it's always 1839 // an error here 1840 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1841 Invalid = true; 1842 SC = VarDecl::None; 1843 } 1844 SCSpec = DS.getStorageClassSpecAsWritten(); 1845 VarDecl::StorageClass SCAsWritten 1846 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1847 1848 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1849 /*IdentifierInfo=*/0, 1850 Context.getTypeDeclType(Record), 1851 TInfo, SC, SCAsWritten); 1852 } 1853 Anon->setImplicit(); 1854 1855 // Add the anonymous struct/union object to the current 1856 // context. We'll be referencing this object when we refer to one of 1857 // its members. 1858 Owner->addDecl(Anon); 1859 1860 // Inject the members of the anonymous struct/union into the owning 1861 // context and into the identifier resolver chain for name lookup 1862 // purposes. 1863 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1864 Invalid = true; 1865 1866 // Mark this as an anonymous struct/union type. Note that we do not 1867 // do this until after we have already checked and injected the 1868 // members of this anonymous struct/union type, because otherwise 1869 // the members could be injected twice: once by DeclContext when it 1870 // builds its lookup table, and once by 1871 // InjectAnonymousStructOrUnionMembers. 1872 Record->setAnonymousStructOrUnion(true); 1873 1874 if (Invalid) 1875 Anon->setInvalidDecl(); 1876 1877 return DeclPtrTy::make(Anon); 1878} 1879 1880 1881/// GetNameForDeclarator - Determine the full declaration name for the 1882/// given Declarator. 1883DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1884 return GetNameFromUnqualifiedId(D.getName()); 1885} 1886 1887/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1888DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1889 switch (Name.getKind()) { 1890 case UnqualifiedId::IK_Identifier: 1891 return DeclarationName(Name.Identifier); 1892 1893 case UnqualifiedId::IK_OperatorFunctionId: 1894 return Context.DeclarationNames.getCXXOperatorName( 1895 Name.OperatorFunctionId.Operator); 1896 1897 case UnqualifiedId::IK_LiteralOperatorId: 1898 return Context.DeclarationNames.getCXXLiteralOperatorName( 1899 Name.Identifier); 1900 1901 case UnqualifiedId::IK_ConversionFunctionId: { 1902 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1903 if (Ty.isNull()) 1904 return DeclarationName(); 1905 1906 return Context.DeclarationNames.getCXXConversionFunctionName( 1907 Context.getCanonicalType(Ty)); 1908 } 1909 1910 case UnqualifiedId::IK_ConstructorName: { 1911 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1912 if (Ty.isNull()) 1913 return DeclarationName(); 1914 1915 return Context.DeclarationNames.getCXXConstructorName( 1916 Context.getCanonicalType(Ty)); 1917 } 1918 1919 case UnqualifiedId::IK_ConstructorTemplateId: { 1920 // In well-formed code, we can only have a constructor 1921 // template-id that refers to the current context, so go there 1922 // to find the actual type being constructed. 1923 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1924 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1925 return DeclarationName(); 1926 1927 // Determine the type of the class being constructed. 1928 QualType CurClassType = Context.getTypeDeclType(CurClass); 1929 1930 // FIXME: Check two things: that the template-id names the same type as 1931 // CurClassType, and that the template-id does not occur when the name 1932 // was qualified. 1933 1934 return Context.DeclarationNames.getCXXConstructorName( 1935 Context.getCanonicalType(CurClassType)); 1936 } 1937 1938 case UnqualifiedId::IK_DestructorName: { 1939 QualType Ty = GetTypeFromParser(Name.DestructorName); 1940 if (Ty.isNull()) 1941 return DeclarationName(); 1942 1943 return Context.DeclarationNames.getCXXDestructorName( 1944 Context.getCanonicalType(Ty)); 1945 } 1946 1947 case UnqualifiedId::IK_TemplateId: { 1948 TemplateName TName 1949 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1950 return Context.getNameForTemplate(TName); 1951 } 1952 } 1953 1954 assert(false && "Unknown name kind"); 1955 return DeclarationName(); 1956} 1957 1958/// isNearlyMatchingFunction - Determine whether the C++ functions 1959/// Declaration and Definition are "nearly" matching. This heuristic 1960/// is used to improve diagnostics in the case where an out-of-line 1961/// function definition doesn't match any declaration within 1962/// the class or namespace. 1963static bool isNearlyMatchingFunction(ASTContext &Context, 1964 FunctionDecl *Declaration, 1965 FunctionDecl *Definition) { 1966 if (Declaration->param_size() != Definition->param_size()) 1967 return false; 1968 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1969 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1970 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1971 1972 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1973 DefParamTy.getNonReferenceType())) 1974 return false; 1975 } 1976 1977 return true; 1978} 1979 1980/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 1981/// declarator needs to be rebuilt in the current instantiation. 1982/// Any bits of declarator which appear before the name are valid for 1983/// consideration here. That's specifically the type in the decl spec 1984/// and the base type in any member-pointer chunks. 1985static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 1986 DeclarationName Name) { 1987 // The types we specifically need to rebuild are: 1988 // - typenames, typeofs, and decltypes 1989 // - types which will become injected class names 1990 // Of course, we also need to rebuild any type referencing such a 1991 // type. It's safest to just say "dependent", but we call out a 1992 // few cases here. 1993 1994 DeclSpec &DS = D.getMutableDeclSpec(); 1995 switch (DS.getTypeSpecType()) { 1996 case DeclSpec::TST_typename: 1997 case DeclSpec::TST_typeofType: 1998 case DeclSpec::TST_typeofExpr: 1999 case DeclSpec::TST_decltype: { 2000 // Grab the type from the parser. 2001 TypeSourceInfo *TSI = 0; 2002 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2003 if (T.isNull() || !T->isDependentType()) break; 2004 2005 // Make sure there's a type source info. This isn't really much 2006 // of a waste; most dependent types should have type source info 2007 // attached already. 2008 if (!TSI) 2009 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2010 2011 // Rebuild the type in the current instantiation. 2012 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2013 if (!TSI) return true; 2014 2015 // Store the new type back in the decl spec. 2016 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2017 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2018 break; 2019 } 2020 2021 default: 2022 // Nothing to do for these decl specs. 2023 break; 2024 } 2025 2026 // It doesn't matter what order we do this in. 2027 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2028 DeclaratorChunk &Chunk = D.getTypeObject(I); 2029 2030 // The only type information in the declarator which can come 2031 // before the declaration name is the base type of a member 2032 // pointer. 2033 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2034 continue; 2035 2036 // Rebuild the scope specifier in-place. 2037 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2038 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2039 return true; 2040 } 2041 2042 return false; 2043} 2044 2045Sema::DeclPtrTy 2046Sema::HandleDeclarator(Scope *S, Declarator &D, 2047 MultiTemplateParamsArg TemplateParamLists, 2048 bool IsFunctionDefinition) { 2049 DeclarationName Name = GetNameForDeclarator(D); 2050 2051 // All of these full declarators require an identifier. If it doesn't have 2052 // one, the ParsedFreeStandingDeclSpec action should be used. 2053 if (!Name) { 2054 if (!D.isInvalidType()) // Reject this if we think it is valid. 2055 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2056 diag::err_declarator_need_ident) 2057 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2058 return DeclPtrTy(); 2059 } 2060 2061 // The scope passed in may not be a decl scope. Zip up the scope tree until 2062 // we find one that is. 2063 while ((S->getFlags() & Scope::DeclScope) == 0 || 2064 (S->getFlags() & Scope::TemplateParamScope) != 0) 2065 S = S->getParent(); 2066 2067 DeclContext *DC = CurContext; 2068 if (D.getCXXScopeSpec().isInvalid()) 2069 D.setInvalidType(); 2070 else if (D.getCXXScopeSpec().isSet()) { 2071 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2072 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2073 if (!DC) { 2074 // If we could not compute the declaration context, it's because the 2075 // declaration context is dependent but does not refer to a class, 2076 // class template, or class template partial specialization. Complain 2077 // and return early, to avoid the coming semantic disaster. 2078 Diag(D.getIdentifierLoc(), 2079 diag::err_template_qualified_declarator_no_match) 2080 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2081 << D.getCXXScopeSpec().getRange(); 2082 return DeclPtrTy(); 2083 } 2084 2085 bool IsDependentContext = DC->isDependentContext(); 2086 2087 if (!IsDependentContext && 2088 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2089 return DeclPtrTy(); 2090 2091 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2092 Diag(D.getIdentifierLoc(), 2093 diag::err_member_def_undefined_record) 2094 << Name << DC << D.getCXXScopeSpec().getRange(); 2095 D.setInvalidType(); 2096 } 2097 2098 // Check whether we need to rebuild the type of the given 2099 // declaration in the current instantiation. 2100 if (EnteringContext && IsDependentContext && 2101 TemplateParamLists.size() != 0) { 2102 ContextRAII SavedContext(*this, DC); 2103 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2104 D.setInvalidType(); 2105 } 2106 } 2107 2108 NamedDecl *New; 2109 2110 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2111 QualType R = TInfo->getType(); 2112 2113 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2114 ForRedeclaration); 2115 2116 // See if this is a redefinition of a variable in the same scope. 2117 if (!D.getCXXScopeSpec().isSet()) { 2118 bool IsLinkageLookup = false; 2119 2120 // If the declaration we're planning to build will be a function 2121 // or object with linkage, then look for another declaration with 2122 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2123 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2124 /* Do nothing*/; 2125 else if (R->isFunctionType()) { 2126 if (CurContext->isFunctionOrMethod() || 2127 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2128 IsLinkageLookup = true; 2129 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2130 IsLinkageLookup = true; 2131 else if (CurContext->getLookupContext()->isTranslationUnit() && 2132 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2133 IsLinkageLookup = true; 2134 2135 if (IsLinkageLookup) 2136 Previous.clear(LookupRedeclarationWithLinkage); 2137 2138 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2139 } else { // Something like "int foo::x;" 2140 LookupQualifiedName(Previous, DC); 2141 2142 // Don't consider using declarations as previous declarations for 2143 // out-of-line members. 2144 RemoveUsingDecls(Previous); 2145 2146 // C++ 7.3.1.2p2: 2147 // Members (including explicit specializations of templates) of a named 2148 // namespace can also be defined outside that namespace by explicit 2149 // qualification of the name being defined, provided that the entity being 2150 // defined was already declared in the namespace and the definition appears 2151 // after the point of declaration in a namespace that encloses the 2152 // declarations namespace. 2153 // 2154 // Note that we only check the context at this point. We don't yet 2155 // have enough information to make sure that PrevDecl is actually 2156 // the declaration we want to match. For example, given: 2157 // 2158 // class X { 2159 // void f(); 2160 // void f(float); 2161 // }; 2162 // 2163 // void X::f(int) { } // ill-formed 2164 // 2165 // In this case, PrevDecl will point to the overload set 2166 // containing the two f's declared in X, but neither of them 2167 // matches. 2168 2169 // First check whether we named the global scope. 2170 if (isa<TranslationUnitDecl>(DC)) { 2171 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2172 << Name << D.getCXXScopeSpec().getRange(); 2173 } else { 2174 DeclContext *Cur = CurContext; 2175 while (isa<LinkageSpecDecl>(Cur)) 2176 Cur = Cur->getParent(); 2177 if (!Cur->Encloses(DC)) { 2178 // The qualifying scope doesn't enclose the original declaration. 2179 // Emit diagnostic based on current scope. 2180 SourceLocation L = D.getIdentifierLoc(); 2181 SourceRange R = D.getCXXScopeSpec().getRange(); 2182 if (isa<FunctionDecl>(Cur)) 2183 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2184 else 2185 Diag(L, diag::err_invalid_declarator_scope) 2186 << Name << cast<NamedDecl>(DC) << R; 2187 D.setInvalidType(); 2188 } 2189 } 2190 } 2191 2192 if (Previous.isSingleResult() && 2193 Previous.getFoundDecl()->isTemplateParameter()) { 2194 // Maybe we will complain about the shadowed template parameter. 2195 if (!D.isInvalidType()) 2196 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2197 Previous.getFoundDecl())) 2198 D.setInvalidType(); 2199 2200 // Just pretend that we didn't see the previous declaration. 2201 Previous.clear(); 2202 } 2203 2204 // In C++, the previous declaration we find might be a tag type 2205 // (class or enum). In this case, the new declaration will hide the 2206 // tag type. Note that this does does not apply if we're declaring a 2207 // typedef (C++ [dcl.typedef]p4). 2208 if (Previous.isSingleTagDecl() && 2209 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2210 Previous.clear(); 2211 2212 bool Redeclaration = false; 2213 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2214 if (TemplateParamLists.size()) { 2215 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2216 return DeclPtrTy(); 2217 } 2218 2219 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2220 } else if (R->isFunctionType()) { 2221 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2222 move(TemplateParamLists), 2223 IsFunctionDefinition, Redeclaration); 2224 } else { 2225 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2226 move(TemplateParamLists), 2227 Redeclaration); 2228 } 2229 2230 if (New == 0) 2231 return DeclPtrTy(); 2232 2233 // If this has an identifier and is not an invalid redeclaration or 2234 // function template specialization, add it to the scope stack. 2235 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2236 PushOnScopeChains(New, S); 2237 2238 return DeclPtrTy::make(New); 2239} 2240 2241/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2242/// types into constant array types in certain situations which would otherwise 2243/// be errors (for GCC compatibility). 2244static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2245 ASTContext &Context, 2246 bool &SizeIsNegative) { 2247 // This method tries to turn a variable array into a constant 2248 // array even when the size isn't an ICE. This is necessary 2249 // for compatibility with code that depends on gcc's buggy 2250 // constant expression folding, like struct {char x[(int)(char*)2];} 2251 SizeIsNegative = false; 2252 2253 QualifierCollector Qs; 2254 const Type *Ty = Qs.strip(T); 2255 2256 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2257 QualType Pointee = PTy->getPointeeType(); 2258 QualType FixedType = 2259 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2260 if (FixedType.isNull()) return FixedType; 2261 FixedType = Context.getPointerType(FixedType); 2262 return Qs.apply(FixedType); 2263 } 2264 2265 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2266 if (!VLATy) 2267 return QualType(); 2268 // FIXME: We should probably handle this case 2269 if (VLATy->getElementType()->isVariablyModifiedType()) 2270 return QualType(); 2271 2272 Expr::EvalResult EvalResult; 2273 if (!VLATy->getSizeExpr() || 2274 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2275 !EvalResult.Val.isInt()) 2276 return QualType(); 2277 2278 llvm::APSInt &Res = EvalResult.Val.getInt(); 2279 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2280 // TODO: preserve the size expression in declarator info 2281 return Context.getConstantArrayType(VLATy->getElementType(), 2282 Res, ArrayType::Normal, 0); 2283 } 2284 2285 SizeIsNegative = true; 2286 return QualType(); 2287} 2288 2289/// \brief Register the given locally-scoped external C declaration so 2290/// that it can be found later for redeclarations 2291void 2292Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2293 const LookupResult &Previous, 2294 Scope *S) { 2295 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2296 "Decl is not a locally-scoped decl!"); 2297 // Note that we have a locally-scoped external with this name. 2298 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2299 2300 if (!Previous.isSingleResult()) 2301 return; 2302 2303 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2304 2305 // If there was a previous declaration of this variable, it may be 2306 // in our identifier chain. Update the identifier chain with the new 2307 // declaration. 2308 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2309 // The previous declaration was found on the identifer resolver 2310 // chain, so remove it from its scope. 2311 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2312 S = S->getParent(); 2313 2314 if (S) 2315 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2316 } 2317} 2318 2319/// \brief Diagnose function specifiers on a declaration of an identifier that 2320/// does not identify a function. 2321void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2322 // FIXME: We should probably indicate the identifier in question to avoid 2323 // confusion for constructs like "inline int a(), b;" 2324 if (D.getDeclSpec().isInlineSpecified()) 2325 Diag(D.getDeclSpec().getInlineSpecLoc(), 2326 diag::err_inline_non_function); 2327 2328 if (D.getDeclSpec().isVirtualSpecified()) 2329 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2330 diag::err_virtual_non_function); 2331 2332 if (D.getDeclSpec().isExplicitSpecified()) 2333 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2334 diag::err_explicit_non_function); 2335} 2336 2337NamedDecl* 2338Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2339 QualType R, TypeSourceInfo *TInfo, 2340 LookupResult &Previous, bool &Redeclaration) { 2341 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2342 if (D.getCXXScopeSpec().isSet()) { 2343 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2344 << D.getCXXScopeSpec().getRange(); 2345 D.setInvalidType(); 2346 // Pretend we didn't see the scope specifier. 2347 DC = CurContext; 2348 Previous.clear(); 2349 } 2350 2351 if (getLangOptions().CPlusPlus) { 2352 // Check that there are no default arguments (C++ only). 2353 CheckExtraCXXDefaultArguments(D); 2354 } 2355 2356 DiagnoseFunctionSpecifiers(D); 2357 2358 if (D.getDeclSpec().isThreadSpecified()) 2359 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2360 2361 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2362 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2363 << D.getName().getSourceRange(); 2364 return 0; 2365 } 2366 2367 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2368 if (!NewTD) return 0; 2369 2370 // Handle attributes prior to checking for duplicates in MergeVarDecl 2371 ProcessDeclAttributes(S, NewTD, D); 2372 2373 // Merge the decl with the existing one if appropriate. If the decl is 2374 // in an outer scope, it isn't the same thing. 2375 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2376 if (!Previous.empty()) { 2377 Redeclaration = true; 2378 MergeTypeDefDecl(NewTD, Previous); 2379 } 2380 2381 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2382 // then it shall have block scope. 2383 QualType T = NewTD->getUnderlyingType(); 2384 if (T->isVariablyModifiedType()) { 2385 setFunctionHasBranchProtectedScope(); 2386 2387 if (S->getFnParent() == 0) { 2388 bool SizeIsNegative; 2389 QualType FixedTy = 2390 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2391 if (!FixedTy.isNull()) { 2392 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2393 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2394 } else { 2395 if (SizeIsNegative) 2396 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2397 else if (T->isVariableArrayType()) 2398 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2399 else 2400 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2401 NewTD->setInvalidDecl(); 2402 } 2403 } 2404 } 2405 2406 // If this is the C FILE type, notify the AST context. 2407 if (IdentifierInfo *II = NewTD->getIdentifier()) 2408 if (!NewTD->isInvalidDecl() && 2409 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2410 if (II->isStr("FILE")) 2411 Context.setFILEDecl(NewTD); 2412 else if (II->isStr("jmp_buf")) 2413 Context.setjmp_bufDecl(NewTD); 2414 else if (II->isStr("sigjmp_buf")) 2415 Context.setsigjmp_bufDecl(NewTD); 2416 } 2417 2418 return NewTD; 2419} 2420 2421/// \brief Determines whether the given declaration is an out-of-scope 2422/// previous declaration. 2423/// 2424/// This routine should be invoked when name lookup has found a 2425/// previous declaration (PrevDecl) that is not in the scope where a 2426/// new declaration by the same name is being introduced. If the new 2427/// declaration occurs in a local scope, previous declarations with 2428/// linkage may still be considered previous declarations (C99 2429/// 6.2.2p4-5, C++ [basic.link]p6). 2430/// 2431/// \param PrevDecl the previous declaration found by name 2432/// lookup 2433/// 2434/// \param DC the context in which the new declaration is being 2435/// declared. 2436/// 2437/// \returns true if PrevDecl is an out-of-scope previous declaration 2438/// for a new delcaration with the same name. 2439static bool 2440isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2441 ASTContext &Context) { 2442 if (!PrevDecl) 2443 return 0; 2444 2445 if (!PrevDecl->hasLinkage()) 2446 return false; 2447 2448 if (Context.getLangOptions().CPlusPlus) { 2449 // C++ [basic.link]p6: 2450 // If there is a visible declaration of an entity with linkage 2451 // having the same name and type, ignoring entities declared 2452 // outside the innermost enclosing namespace scope, the block 2453 // scope declaration declares that same entity and receives the 2454 // linkage of the previous declaration. 2455 DeclContext *OuterContext = DC->getLookupContext(); 2456 if (!OuterContext->isFunctionOrMethod()) 2457 // This rule only applies to block-scope declarations. 2458 return false; 2459 else { 2460 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2461 if (PrevOuterContext->isRecord()) 2462 // We found a member function: ignore it. 2463 return false; 2464 else { 2465 // Find the innermost enclosing namespace for the new and 2466 // previous declarations. 2467 while (!OuterContext->isFileContext()) 2468 OuterContext = OuterContext->getParent(); 2469 while (!PrevOuterContext->isFileContext()) 2470 PrevOuterContext = PrevOuterContext->getParent(); 2471 2472 // The previous declaration is in a different namespace, so it 2473 // isn't the same function. 2474 if (OuterContext->getPrimaryContext() != 2475 PrevOuterContext->getPrimaryContext()) 2476 return false; 2477 } 2478 } 2479 } 2480 2481 return true; 2482} 2483 2484static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2485 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2486 if (!SS.isSet()) return; 2487 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2488 SS.getRange()); 2489} 2490 2491NamedDecl* 2492Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2493 QualType R, TypeSourceInfo *TInfo, 2494 LookupResult &Previous, 2495 MultiTemplateParamsArg TemplateParamLists, 2496 bool &Redeclaration) { 2497 DeclarationName Name = GetNameForDeclarator(D); 2498 2499 // Check that there are no default arguments (C++ only). 2500 if (getLangOptions().CPlusPlus) 2501 CheckExtraCXXDefaultArguments(D); 2502 2503 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2504 assert(SCSpec != DeclSpec::SCS_typedef && 2505 "Parser allowed 'typedef' as storage class VarDecl."); 2506 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2507 if (SCSpec == DeclSpec::SCS_mutable) { 2508 // mutable can only appear on non-static class members, so it's always 2509 // an error here 2510 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2511 D.setInvalidType(); 2512 SC = VarDecl::None; 2513 } 2514 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2515 VarDecl::StorageClass SCAsWritten 2516 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2517 2518 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2519 if (!II) { 2520 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2521 << Name.getAsString(); 2522 return 0; 2523 } 2524 2525 DiagnoseFunctionSpecifiers(D); 2526 2527 if (!DC->isRecord() && S->getFnParent() == 0) { 2528 // C99 6.9p2: The storage-class specifiers auto and register shall not 2529 // appear in the declaration specifiers in an external declaration. 2530 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2531 2532 // If this is a register variable with an asm label specified, then this 2533 // is a GNU extension. 2534 if (SC == VarDecl::Register && D.getAsmLabel()) 2535 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2536 else 2537 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2538 D.setInvalidType(); 2539 } 2540 } 2541 if (DC->isRecord() && !CurContext->isRecord()) { 2542 // This is an out-of-line definition of a static data member. 2543 if (SC == VarDecl::Static) { 2544 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2545 diag::err_static_out_of_line) 2546 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2547 } else if (SC == VarDecl::None) 2548 SC = VarDecl::Static; 2549 } 2550 if (SC == VarDecl::Static) { 2551 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2552 if (RD->isLocalClass()) 2553 Diag(D.getIdentifierLoc(), 2554 diag::err_static_data_member_not_allowed_in_local_class) 2555 << Name << RD->getDeclName(); 2556 } 2557 } 2558 2559 // Match up the template parameter lists with the scope specifier, then 2560 // determine whether we have a template or a template specialization. 2561 bool isExplicitSpecialization = false; 2562 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2563 bool Invalid = false; 2564 if (TemplateParameterList *TemplateParams 2565 = MatchTemplateParametersToScopeSpecifier( 2566 D.getDeclSpec().getSourceRange().getBegin(), 2567 D.getCXXScopeSpec(), 2568 (TemplateParameterList**)TemplateParamLists.get(), 2569 TemplateParamLists.size(), 2570 /*never a friend*/ false, 2571 isExplicitSpecialization, 2572 Invalid)) { 2573 // All but one template parameter lists have been matching. 2574 --NumMatchedTemplateParamLists; 2575 2576 if (TemplateParams->size() > 0) { 2577 // There is no such thing as a variable template. 2578 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2579 << II 2580 << SourceRange(TemplateParams->getTemplateLoc(), 2581 TemplateParams->getRAngleLoc()); 2582 return 0; 2583 } else { 2584 // There is an extraneous 'template<>' for this variable. Complain 2585 // about it, but allow the declaration of the variable. 2586 Diag(TemplateParams->getTemplateLoc(), 2587 diag::err_template_variable_noparams) 2588 << II 2589 << SourceRange(TemplateParams->getTemplateLoc(), 2590 TemplateParams->getRAngleLoc()); 2591 2592 isExplicitSpecialization = true; 2593 } 2594 } 2595 2596 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2597 II, R, TInfo, SC, SCAsWritten); 2598 2599 if (D.isInvalidType() || Invalid) 2600 NewVD->setInvalidDecl(); 2601 2602 SetNestedNameSpecifier(NewVD, D); 2603 2604 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2605 NewVD->setTemplateParameterListsInfo(Context, 2606 NumMatchedTemplateParamLists, 2607 (TemplateParameterList**)TemplateParamLists.release()); 2608 } 2609 2610 if (D.getDeclSpec().isThreadSpecified()) { 2611 if (NewVD->hasLocalStorage()) 2612 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2613 else if (!Context.Target.isTLSSupported()) 2614 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2615 else 2616 NewVD->setThreadSpecified(true); 2617 } 2618 2619 // Set the lexical context. If the declarator has a C++ scope specifier, the 2620 // lexical context will be different from the semantic context. 2621 NewVD->setLexicalDeclContext(CurContext); 2622 2623 // Handle attributes prior to checking for duplicates in MergeVarDecl 2624 ProcessDeclAttributes(S, NewVD, D); 2625 2626 // Handle GNU asm-label extension (encoded as an attribute). 2627 if (Expr *E = (Expr*) D.getAsmLabel()) { 2628 // The parser guarantees this is a string. 2629 StringLiteral *SE = cast<StringLiteral>(E); 2630 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2631 } 2632 2633 // Diagnose shadowed variables before filtering for scope. 2634 if (!D.getCXXScopeSpec().isSet()) 2635 CheckShadow(S, NewVD, Previous); 2636 2637 // Don't consider existing declarations that are in a different 2638 // scope and are out-of-semantic-context declarations (if the new 2639 // declaration has linkage). 2640 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2641 2642 // Merge the decl with the existing one if appropriate. 2643 if (!Previous.empty()) { 2644 if (Previous.isSingleResult() && 2645 isa<FieldDecl>(Previous.getFoundDecl()) && 2646 D.getCXXScopeSpec().isSet()) { 2647 // The user tried to define a non-static data member 2648 // out-of-line (C++ [dcl.meaning]p1). 2649 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2650 << D.getCXXScopeSpec().getRange(); 2651 Previous.clear(); 2652 NewVD->setInvalidDecl(); 2653 } 2654 } else if (D.getCXXScopeSpec().isSet()) { 2655 // No previous declaration in the qualifying scope. 2656 Diag(D.getIdentifierLoc(), diag::err_no_member) 2657 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2658 << D.getCXXScopeSpec().getRange(); 2659 NewVD->setInvalidDecl(); 2660 } 2661 2662 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2663 2664 // This is an explicit specialization of a static data member. Check it. 2665 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2666 CheckMemberSpecialization(NewVD, Previous)) 2667 NewVD->setInvalidDecl(); 2668 2669 // attributes declared post-definition are currently ignored 2670 if (Previous.isSingleResult()) { 2671 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2672 if (Def && (Def = Def->getDefinition()) && 2673 Def != NewVD && D.hasAttributes()) { 2674 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2675 Diag(Def->getLocation(), diag::note_previous_definition); 2676 } 2677 } 2678 2679 // If this is a locally-scoped extern C variable, update the map of 2680 // such variables. 2681 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2682 !NewVD->isInvalidDecl()) 2683 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2684 2685 // If there's a #pragma GCC visibility in scope, and this isn't a class 2686 // member, set the visibility of this variable. 2687 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2688 AddPushedVisibilityAttribute(NewVD); 2689 2690 return NewVD; 2691} 2692 2693/// \brief Diagnose variable or built-in function shadowing. Implements 2694/// -Wshadow. 2695/// 2696/// This method is called whenever a VarDecl is added to a "useful" 2697/// scope. 2698/// 2699/// \param S the scope in which the shadowing name is being declared 2700/// \param R the lookup of the name 2701/// 2702void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2703 // Return if warning is ignored. 2704 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2705 return; 2706 2707 // Don't diagnose declarations at file scope. The scope might not 2708 // have a DeclContext if (e.g.) we're parsing a function prototype. 2709 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2710 if (NewDC && NewDC->isFileContext()) 2711 return; 2712 2713 // Only diagnose if we're shadowing an unambiguous field or variable. 2714 if (R.getResultKind() != LookupResult::Found) 2715 return; 2716 2717 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2718 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2719 return; 2720 2721 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2722 2723 // Only warn about certain kinds of shadowing for class members. 2724 if (NewDC && NewDC->isRecord()) { 2725 // In particular, don't warn about shadowing non-class members. 2726 if (!OldDC->isRecord()) 2727 return; 2728 2729 // TODO: should we warn about static data members shadowing 2730 // static data members from base classes? 2731 2732 // TODO: don't diagnose for inaccessible shadowed members. 2733 // This is hard to do perfectly because we might friend the 2734 // shadowing context, but that's just a false negative. 2735 } 2736 2737 // Determine what kind of declaration we're shadowing. 2738 unsigned Kind; 2739 if (isa<RecordDecl>(OldDC)) { 2740 if (isa<FieldDecl>(ShadowedDecl)) 2741 Kind = 3; // field 2742 else 2743 Kind = 2; // static data member 2744 } else if (OldDC->isFileContext()) 2745 Kind = 1; // global 2746 else 2747 Kind = 0; // local 2748 2749 DeclarationName Name = R.getLookupName(); 2750 2751 // Emit warning and note. 2752 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2753 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2754} 2755 2756/// \brief Check -Wshadow without the advantage of a previous lookup. 2757void Sema::CheckShadow(Scope *S, VarDecl *D) { 2758 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2759 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2760 LookupName(R, S); 2761 CheckShadow(S, D, R); 2762} 2763 2764/// \brief Perform semantic checking on a newly-created variable 2765/// declaration. 2766/// 2767/// This routine performs all of the type-checking required for a 2768/// variable declaration once it has been built. It is used both to 2769/// check variables after they have been parsed and their declarators 2770/// have been translated into a declaration, and to check variables 2771/// that have been instantiated from a template. 2772/// 2773/// Sets NewVD->isInvalidDecl() if an error was encountered. 2774void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2775 LookupResult &Previous, 2776 bool &Redeclaration) { 2777 // If the decl is already known invalid, don't check it. 2778 if (NewVD->isInvalidDecl()) 2779 return; 2780 2781 QualType T = NewVD->getType(); 2782 2783 if (T->isObjCObjectType()) { 2784 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2785 return NewVD->setInvalidDecl(); 2786 } 2787 2788 // Emit an error if an address space was applied to decl with local storage. 2789 // This includes arrays of objects with address space qualifiers, but not 2790 // automatic variables that point to other address spaces. 2791 // ISO/IEC TR 18037 S5.1.2 2792 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2793 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2794 return NewVD->setInvalidDecl(); 2795 } 2796 2797 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2798 && !NewVD->hasAttr<BlocksAttr>()) 2799 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2800 2801 bool isVM = T->isVariablyModifiedType(); 2802 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2803 NewVD->hasAttr<BlocksAttr>()) 2804 setFunctionHasBranchProtectedScope(); 2805 2806 if ((isVM && NewVD->hasLinkage()) || 2807 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2808 bool SizeIsNegative; 2809 QualType FixedTy = 2810 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2811 2812 if (FixedTy.isNull() && T->isVariableArrayType()) { 2813 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2814 // FIXME: This won't give the correct result for 2815 // int a[10][n]; 2816 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2817 2818 if (NewVD->isFileVarDecl()) 2819 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2820 << SizeRange; 2821 else if (NewVD->getStorageClass() == VarDecl::Static) 2822 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2823 << SizeRange; 2824 else 2825 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2826 << SizeRange; 2827 return NewVD->setInvalidDecl(); 2828 } 2829 2830 if (FixedTy.isNull()) { 2831 if (NewVD->isFileVarDecl()) 2832 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2833 else 2834 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2835 return NewVD->setInvalidDecl(); 2836 } 2837 2838 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2839 NewVD->setType(FixedTy); 2840 } 2841 2842 if (Previous.empty() && NewVD->isExternC()) { 2843 // Since we did not find anything by this name and we're declaring 2844 // an extern "C" variable, look for a non-visible extern "C" 2845 // declaration with the same name. 2846 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2847 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2848 if (Pos != LocallyScopedExternalDecls.end()) 2849 Previous.addDecl(Pos->second); 2850 } 2851 2852 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2853 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2854 << T; 2855 return NewVD->setInvalidDecl(); 2856 } 2857 2858 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2859 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2860 return NewVD->setInvalidDecl(); 2861 } 2862 2863 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2864 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2865 return NewVD->setInvalidDecl(); 2866 } 2867 2868 // Function pointers and references cannot have qualified function type, only 2869 // function pointer-to-members can do that. 2870 QualType Pointee; 2871 unsigned PtrOrRef = 0; 2872 if (const PointerType *Ptr = T->getAs<PointerType>()) 2873 Pointee = Ptr->getPointeeType(); 2874 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 2875 Pointee = Ref->getPointeeType(); 2876 PtrOrRef = 1; 2877 } 2878 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 2879 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 2880 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 2881 << PtrOrRef; 2882 return NewVD->setInvalidDecl(); 2883 } 2884 2885 if (!Previous.empty()) { 2886 Redeclaration = true; 2887 MergeVarDecl(NewVD, Previous); 2888 } 2889} 2890 2891/// \brief Data used with FindOverriddenMethod 2892struct FindOverriddenMethodData { 2893 Sema *S; 2894 CXXMethodDecl *Method; 2895}; 2896 2897/// \brief Member lookup function that determines whether a given C++ 2898/// method overrides a method in a base class, to be used with 2899/// CXXRecordDecl::lookupInBases(). 2900static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2901 CXXBasePath &Path, 2902 void *UserData) { 2903 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2904 2905 FindOverriddenMethodData *Data 2906 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2907 2908 DeclarationName Name = Data->Method->getDeclName(); 2909 2910 // FIXME: Do we care about other names here too? 2911 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2912 // We really want to find the base class destructor here. 2913 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2914 CanQualType CT = Data->S->Context.getCanonicalType(T); 2915 2916 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2917 } 2918 2919 for (Path.Decls = BaseRecord->lookup(Name); 2920 Path.Decls.first != Path.Decls.second; 2921 ++Path.Decls.first) { 2922 NamedDecl *D = *Path.Decls.first; 2923 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 2924 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 2925 return true; 2926 } 2927 } 2928 2929 return false; 2930} 2931 2932/// AddOverriddenMethods - See if a method overrides any in the base classes, 2933/// and if so, check that it's a valid override and remember it. 2934void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2935 // Look for virtual methods in base classes that this method might override. 2936 CXXBasePaths Paths; 2937 FindOverriddenMethodData Data; 2938 Data.Method = MD; 2939 Data.S = this; 2940 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2941 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2942 E = Paths.found_decls_end(); I != E; ++I) { 2943 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2944 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2945 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2946 !CheckOverridingFunctionAttributes(MD, OldMD)) 2947 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2948 } 2949 } 2950 } 2951} 2952 2953NamedDecl* 2954Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2955 QualType R, TypeSourceInfo *TInfo, 2956 LookupResult &Previous, 2957 MultiTemplateParamsArg TemplateParamLists, 2958 bool IsFunctionDefinition, bool &Redeclaration) { 2959 assert(R.getTypePtr()->isFunctionType()); 2960 2961 DeclarationName Name = GetNameForDeclarator(D); 2962 FunctionDecl::StorageClass SC = FunctionDecl::None; 2963 switch (D.getDeclSpec().getStorageClassSpec()) { 2964 default: assert(0 && "Unknown storage class!"); 2965 case DeclSpec::SCS_auto: 2966 case DeclSpec::SCS_register: 2967 case DeclSpec::SCS_mutable: 2968 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2969 diag::err_typecheck_sclass_func); 2970 D.setInvalidType(); 2971 break; 2972 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2973 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2974 case DeclSpec::SCS_static: { 2975 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2976 // C99 6.7.1p5: 2977 // The declaration of an identifier for a function that has 2978 // block scope shall have no explicit storage-class specifier 2979 // other than extern 2980 // See also (C++ [dcl.stc]p4). 2981 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2982 diag::err_static_block_func); 2983 SC = FunctionDecl::None; 2984 } else 2985 SC = FunctionDecl::Static; 2986 break; 2987 } 2988 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2989 } 2990 2991 if (D.getDeclSpec().isThreadSpecified()) 2992 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2993 2994 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2995 bool isInline = D.getDeclSpec().isInlineSpecified(); 2996 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2997 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2998 2999 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3000 FunctionDecl::StorageClass SCAsWritten 3001 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3002 3003 // Check that the return type is not an abstract class type. 3004 // For record types, this is done by the AbstractClassUsageDiagnoser once 3005 // the class has been completely parsed. 3006 if (!DC->isRecord() && 3007 RequireNonAbstractType(D.getIdentifierLoc(), 3008 R->getAs<FunctionType>()->getResultType(), 3009 diag::err_abstract_type_in_decl, 3010 AbstractReturnType)) 3011 D.setInvalidType(); 3012 3013 // Do not allow returning a objc interface by-value. 3014 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3015 Diag(D.getIdentifierLoc(), 3016 diag::err_object_cannot_be_passed_returned_by_value) << 0 3017 << R->getAs<FunctionType>()->getResultType(); 3018 D.setInvalidType(); 3019 } 3020 3021 bool isVirtualOkay = false; 3022 FunctionDecl *NewFD; 3023 3024 if (isFriend) { 3025 // C++ [class.friend]p5 3026 // A function can be defined in a friend declaration of a 3027 // class . . . . Such a function is implicitly inline. 3028 isInline |= IsFunctionDefinition; 3029 } 3030 3031 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3032 // This is a C++ constructor declaration. 3033 assert(DC->isRecord() && 3034 "Constructors can only be declared in a member context"); 3035 3036 R = CheckConstructorDeclarator(D, R, SC); 3037 3038 // Create the new declaration 3039 NewFD = CXXConstructorDecl::Create(Context, 3040 cast<CXXRecordDecl>(DC), 3041 D.getIdentifierLoc(), Name, R, TInfo, 3042 isExplicit, isInline, 3043 /*isImplicitlyDeclared=*/false); 3044 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3045 // This is a C++ destructor declaration. 3046 if (DC->isRecord()) { 3047 R = CheckDestructorDeclarator(D, R, SC); 3048 3049 NewFD = CXXDestructorDecl::Create(Context, 3050 cast<CXXRecordDecl>(DC), 3051 D.getIdentifierLoc(), Name, R, 3052 isInline, 3053 /*isImplicitlyDeclared=*/false); 3054 NewFD->setTypeSourceInfo(TInfo); 3055 3056 isVirtualOkay = true; 3057 } else { 3058 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3059 3060 // Create a FunctionDecl to satisfy the function definition parsing 3061 // code path. 3062 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3063 Name, R, TInfo, SC, SCAsWritten, isInline, 3064 /*hasPrototype=*/true); 3065 D.setInvalidType(); 3066 } 3067 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3068 if (!DC->isRecord()) { 3069 Diag(D.getIdentifierLoc(), 3070 diag::err_conv_function_not_member); 3071 return 0; 3072 } 3073 3074 CheckConversionDeclarator(D, R, SC); 3075 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3076 D.getIdentifierLoc(), Name, R, TInfo, 3077 isInline, isExplicit); 3078 3079 isVirtualOkay = true; 3080 } else if (DC->isRecord()) { 3081 // If the of the function is the same as the name of the record, then this 3082 // must be an invalid constructor that has a return type. 3083 // (The parser checks for a return type and makes the declarator a 3084 // constructor if it has no return type). 3085 // must have an invalid constructor that has a return type 3086 if (Name.getAsIdentifierInfo() && 3087 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3088 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3089 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3090 << SourceRange(D.getIdentifierLoc()); 3091 return 0; 3092 } 3093 3094 bool isStatic = SC == FunctionDecl::Static; 3095 3096 // [class.free]p1: 3097 // Any allocation function for a class T is a static member 3098 // (even if not explicitly declared static). 3099 if (Name.getCXXOverloadedOperator() == OO_New || 3100 Name.getCXXOverloadedOperator() == OO_Array_New) 3101 isStatic = true; 3102 3103 // [class.free]p6 Any deallocation function for a class X is a static member 3104 // (even if not explicitly declared static). 3105 if (Name.getCXXOverloadedOperator() == OO_Delete || 3106 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3107 isStatic = true; 3108 3109 // This is a C++ method declaration. 3110 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3111 D.getIdentifierLoc(), Name, R, TInfo, 3112 isStatic, SCAsWritten, isInline); 3113 3114 isVirtualOkay = !isStatic; 3115 } else { 3116 // Determine whether the function was written with a 3117 // prototype. This true when: 3118 // - we're in C++ (where every function has a prototype), 3119 // - there is a prototype in the declarator, or 3120 // - the type R of the function is some kind of typedef or other reference 3121 // to a type name (which eventually refers to a function type). 3122 bool HasPrototype = 3123 getLangOptions().CPlusPlus || 3124 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3125 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3126 3127 NewFD = FunctionDecl::Create(Context, DC, 3128 D.getIdentifierLoc(), 3129 Name, R, TInfo, SC, SCAsWritten, isInline, 3130 HasPrototype); 3131 } 3132 3133 if (D.isInvalidType()) 3134 NewFD->setInvalidDecl(); 3135 3136 SetNestedNameSpecifier(NewFD, D); 3137 3138 // Set the lexical context. If the declarator has a C++ 3139 // scope specifier, or is the object of a friend declaration, the 3140 // lexical context will be different from the semantic context. 3141 NewFD->setLexicalDeclContext(CurContext); 3142 3143 // Match up the template parameter lists with the scope specifier, then 3144 // determine whether we have a template or a template specialization. 3145 FunctionTemplateDecl *FunctionTemplate = 0; 3146 bool isExplicitSpecialization = false; 3147 bool isFunctionTemplateSpecialization = false; 3148 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3149 bool Invalid = false; 3150 if (TemplateParameterList *TemplateParams 3151 = MatchTemplateParametersToScopeSpecifier( 3152 D.getDeclSpec().getSourceRange().getBegin(), 3153 D.getCXXScopeSpec(), 3154 (TemplateParameterList**)TemplateParamLists.get(), 3155 TemplateParamLists.size(), 3156 isFriend, 3157 isExplicitSpecialization, 3158 Invalid)) { 3159 // All but one template parameter lists have been matching. 3160 --NumMatchedTemplateParamLists; 3161 3162 if (TemplateParams->size() > 0) { 3163 // This is a function template 3164 3165 // Check that we can declare a template here. 3166 if (CheckTemplateDeclScope(S, TemplateParams)) 3167 return 0; 3168 3169 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3170 NewFD->getLocation(), 3171 Name, TemplateParams, 3172 NewFD); 3173 FunctionTemplate->setLexicalDeclContext(CurContext); 3174 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3175 } else { 3176 // This is a function template specialization. 3177 isFunctionTemplateSpecialization = true; 3178 3179 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3180 if (isFriend && isFunctionTemplateSpecialization) { 3181 // We want to remove the "template<>", found here. 3182 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3183 3184 // If we remove the template<> and the name is not a 3185 // template-id, we're actually silently creating a problem: 3186 // the friend declaration will refer to an untemplated decl, 3187 // and clearly the user wants a template specialization. So 3188 // we need to insert '<>' after the name. 3189 SourceLocation InsertLoc; 3190 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3191 InsertLoc = D.getName().getSourceRange().getEnd(); 3192 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3193 } 3194 3195 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3196 << Name << RemoveRange 3197 << FixItHint::CreateRemoval(RemoveRange) 3198 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3199 } 3200 } 3201 } 3202 3203 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3204 NewFD->setTemplateParameterListsInfo(Context, 3205 NumMatchedTemplateParamLists, 3206 (TemplateParameterList**)TemplateParamLists.release()); 3207 } 3208 3209 if (Invalid) { 3210 NewFD->setInvalidDecl(); 3211 if (FunctionTemplate) 3212 FunctionTemplate->setInvalidDecl(); 3213 } 3214 3215 // C++ [dcl.fct.spec]p5: 3216 // The virtual specifier shall only be used in declarations of 3217 // nonstatic class member functions that appear within a 3218 // member-specification of a class declaration; see 10.3. 3219 // 3220 if (isVirtual && !NewFD->isInvalidDecl()) { 3221 if (!isVirtualOkay) { 3222 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3223 diag::err_virtual_non_function); 3224 } else if (!CurContext->isRecord()) { 3225 // 'virtual' was specified outside of the class. 3226 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3227 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3228 } else { 3229 // Okay: Add virtual to the method. 3230 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3231 CurClass->setMethodAsVirtual(NewFD); 3232 } 3233 } 3234 3235 // C++ [dcl.fct.spec]p6: 3236 // The explicit specifier shall be used only in the declaration of a 3237 // constructor or conversion function within its class definition; see 12.3.1 3238 // and 12.3.2. 3239 if (isExplicit && !NewFD->isInvalidDecl()) { 3240 if (!CurContext->isRecord()) { 3241 // 'explicit' was specified outside of the class. 3242 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3243 diag::err_explicit_out_of_class) 3244 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3245 } else if (!isa<CXXConstructorDecl>(NewFD) && 3246 !isa<CXXConversionDecl>(NewFD)) { 3247 // 'explicit' was specified on a function that wasn't a constructor 3248 // or conversion function. 3249 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3250 diag::err_explicit_non_ctor_or_conv_function) 3251 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3252 } 3253 } 3254 3255 // Filter out previous declarations that don't match the scope. 3256 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3257 3258 if (isFriend) { 3259 // DC is the namespace in which the function is being declared. 3260 assert((DC->isFileContext() || !Previous.empty()) && 3261 "previously-undeclared friend function being created " 3262 "in a non-namespace context"); 3263 3264 // For now, claim that the objects have no previous declaration. 3265 if (FunctionTemplate) { 3266 FunctionTemplate->setObjectOfFriendDecl(false); 3267 FunctionTemplate->setAccess(AS_public); 3268 } 3269 NewFD->setObjectOfFriendDecl(false); 3270 NewFD->setAccess(AS_public); 3271 } 3272 3273 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3274 !CurContext->isRecord()) { 3275 // C++ [class.static]p1: 3276 // A data or function member of a class may be declared static 3277 // in a class definition, in which case it is a static member of 3278 // the class. 3279 3280 // Complain about the 'static' specifier if it's on an out-of-line 3281 // member function definition. 3282 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3283 diag::err_static_out_of_line) 3284 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3285 } 3286 3287 // Handle GNU asm-label extension (encoded as an attribute). 3288 if (Expr *E = (Expr*) D.getAsmLabel()) { 3289 // The parser guarantees this is a string. 3290 StringLiteral *SE = cast<StringLiteral>(E); 3291 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3292 } 3293 3294 // Copy the parameter declarations from the declarator D to the function 3295 // declaration NewFD, if they are available. First scavenge them into Params. 3296 llvm::SmallVector<ParmVarDecl*, 16> Params; 3297 if (D.getNumTypeObjects() > 0) { 3298 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3299 3300 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3301 // function that takes no arguments, not a function that takes a 3302 // single void argument. 3303 // We let through "const void" here because Sema::GetTypeForDeclarator 3304 // already checks for that case. 3305 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3306 FTI.ArgInfo[0].Param && 3307 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3308 // Empty arg list, don't push any params. 3309 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3310 3311 // In C++, the empty parameter-type-list must be spelled "void"; a 3312 // typedef of void is not permitted. 3313 if (getLangOptions().CPlusPlus && 3314 Param->getType().getUnqualifiedType() != Context.VoidTy) 3315 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3316 // FIXME: Leaks decl? 3317 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3318 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3319 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3320 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3321 Param->setDeclContext(NewFD); 3322 Params.push_back(Param); 3323 3324 if (Param->isInvalidDecl()) 3325 NewFD->setInvalidDecl(); 3326 } 3327 } 3328 3329 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3330 // When we're declaring a function with a typedef, typeof, etc as in the 3331 // following example, we'll need to synthesize (unnamed) 3332 // parameters for use in the declaration. 3333 // 3334 // @code 3335 // typedef void fn(int); 3336 // fn f; 3337 // @endcode 3338 3339 // Synthesize a parameter for each argument type. 3340 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3341 AE = FT->arg_type_end(); AI != AE; ++AI) { 3342 ParmVarDecl *Param = 3343 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3344 Params.push_back(Param); 3345 } 3346 } else { 3347 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3348 "Should not need args for typedef of non-prototype fn"); 3349 } 3350 // Finally, we know we have the right number of parameters, install them. 3351 NewFD->setParams(Params.data(), Params.size()); 3352 3353 // If the declarator is a template-id, translate the parser's template 3354 // argument list into our AST format. 3355 bool HasExplicitTemplateArgs = false; 3356 TemplateArgumentListInfo TemplateArgs; 3357 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3358 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3359 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3360 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3361 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3362 TemplateId->getTemplateArgs(), 3363 TemplateId->NumArgs); 3364 translateTemplateArguments(TemplateArgsPtr, 3365 TemplateArgs); 3366 TemplateArgsPtr.release(); 3367 3368 HasExplicitTemplateArgs = true; 3369 3370 if (FunctionTemplate) { 3371 // FIXME: Diagnose function template with explicit template 3372 // arguments. 3373 HasExplicitTemplateArgs = false; 3374 } else if (!isFunctionTemplateSpecialization && 3375 !D.getDeclSpec().isFriendSpecified()) { 3376 // We have encountered something that the user meant to be a 3377 // specialization (because it has explicitly-specified template 3378 // arguments) but that was not introduced with a "template<>" (or had 3379 // too few of them). 3380 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3381 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3382 << FixItHint::CreateInsertion( 3383 D.getDeclSpec().getSourceRange().getBegin(), 3384 "template<> "); 3385 isFunctionTemplateSpecialization = true; 3386 } else { 3387 // "friend void foo<>(int);" is an implicit specialization decl. 3388 isFunctionTemplateSpecialization = true; 3389 } 3390 } else if (isFriend && isFunctionTemplateSpecialization) { 3391 // This combination is only possible in a recovery case; the user 3392 // wrote something like: 3393 // template <> friend void foo(int); 3394 // which we're recovering from as if the user had written: 3395 // friend void foo<>(int); 3396 // Go ahead and fake up a template id. 3397 HasExplicitTemplateArgs = true; 3398 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3399 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3400 } 3401 3402 // If it's a friend (and only if it's a friend), it's possible 3403 // that either the specialized function type or the specialized 3404 // template is dependent, and therefore matching will fail. In 3405 // this case, don't check the specialization yet. 3406 if (isFunctionTemplateSpecialization && isFriend && 3407 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3408 assert(HasExplicitTemplateArgs && 3409 "friend function specialization without template args"); 3410 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3411 Previous)) 3412 NewFD->setInvalidDecl(); 3413 } else if (isFunctionTemplateSpecialization) { 3414 if (CheckFunctionTemplateSpecialization(NewFD, 3415 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3416 Previous)) 3417 NewFD->setInvalidDecl(); 3418 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3419 if (CheckMemberSpecialization(NewFD, Previous)) 3420 NewFD->setInvalidDecl(); 3421 } 3422 3423 // Perform semantic checking on the function declaration. 3424 bool OverloadableAttrRequired = false; // FIXME: HACK! 3425 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3426 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3427 3428 assert((NewFD->isInvalidDecl() || !Redeclaration || 3429 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3430 "previous declaration set still overloaded"); 3431 3432 NamedDecl *PrincipalDecl = (FunctionTemplate 3433 ? cast<NamedDecl>(FunctionTemplate) 3434 : NewFD); 3435 3436 if (isFriend && Redeclaration) { 3437 AccessSpecifier Access = AS_public; 3438 if (!NewFD->isInvalidDecl()) 3439 Access = NewFD->getPreviousDeclaration()->getAccess(); 3440 3441 NewFD->setAccess(Access); 3442 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3443 3444 PrincipalDecl->setObjectOfFriendDecl(true); 3445 } 3446 3447 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3448 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3449 PrincipalDecl->setNonMemberOperator(); 3450 3451 // If we have a function template, check the template parameter 3452 // list. This will check and merge default template arguments. 3453 if (FunctionTemplate) { 3454 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3455 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3456 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3457 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3458 : TPC_FunctionTemplate); 3459 } 3460 3461 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3462 // Fake up an access specifier if it's supposed to be a class member. 3463 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3464 NewFD->setAccess(AS_public); 3465 3466 // An out-of-line member function declaration must also be a 3467 // definition (C++ [dcl.meaning]p1). 3468 // Note that this is not the case for explicit specializations of 3469 // function templates or member functions of class templates, per 3470 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3471 // for compatibility with old SWIG code which likes to generate them. 3472 if (!IsFunctionDefinition && !isFriend && 3473 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3474 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3475 << D.getCXXScopeSpec().getRange(); 3476 } 3477 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3478 // The user tried to provide an out-of-line definition for a 3479 // function that is a member of a class or namespace, but there 3480 // was no such member function declared (C++ [class.mfct]p2, 3481 // C++ [namespace.memdef]p2). For example: 3482 // 3483 // class X { 3484 // void f() const; 3485 // }; 3486 // 3487 // void X::f() { } // ill-formed 3488 // 3489 // Complain about this problem, and attempt to suggest close 3490 // matches (e.g., those that differ only in cv-qualifiers and 3491 // whether the parameter types are references). 3492 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3493 << Name << DC << D.getCXXScopeSpec().getRange(); 3494 NewFD->setInvalidDecl(); 3495 3496 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3497 ForRedeclaration); 3498 LookupQualifiedName(Prev, DC); 3499 assert(!Prev.isAmbiguous() && 3500 "Cannot have an ambiguity in previous-declaration lookup"); 3501 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3502 Func != FuncEnd; ++Func) { 3503 if (isa<FunctionDecl>(*Func) && 3504 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3505 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3506 } 3507 } 3508 } 3509 3510 // Handle attributes. We need to have merged decls when handling attributes 3511 // (for example to check for conflicts, etc). 3512 // FIXME: This needs to happen before we merge declarations. Then, 3513 // let attribute merging cope with attribute conflicts. 3514 ProcessDeclAttributes(S, NewFD, D); 3515 3516 // attributes declared post-definition are currently ignored 3517 if (Redeclaration && Previous.isSingleResult()) { 3518 const FunctionDecl *Def; 3519 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3520 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3521 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3522 Diag(Def->getLocation(), diag::note_previous_definition); 3523 } 3524 } 3525 3526 AddKnownFunctionAttributes(NewFD); 3527 3528 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3529 // If a function name is overloadable in C, then every function 3530 // with that name must be marked "overloadable". 3531 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3532 << Redeclaration << NewFD; 3533 if (!Previous.empty()) 3534 Diag(Previous.getRepresentativeDecl()->getLocation(), 3535 diag::note_attribute_overloadable_prev_overload); 3536 NewFD->addAttr(::new (Context) OverloadableAttr()); 3537 } 3538 3539 // If there's a #pragma GCC visibility in scope, and this isn't a class 3540 // member, set the visibility of this function. 3541 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3542 AddPushedVisibilityAttribute(NewFD); 3543 3544 // If this is a locally-scoped extern C function, update the 3545 // map of such names. 3546 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3547 && !NewFD->isInvalidDecl()) 3548 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3549 3550 // Set this FunctionDecl's range up to the right paren. 3551 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3552 3553 if (FunctionTemplate && NewFD->isInvalidDecl()) 3554 FunctionTemplate->setInvalidDecl(); 3555 3556 if (FunctionTemplate) 3557 return FunctionTemplate; 3558 3559 3560 // Keep track of static, non-inlined function definitions that 3561 // have not been used. We will warn later. 3562 // FIXME: Also include static functions declared but not defined. 3563 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3564 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3565 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3566 && !NewFD->hasAttr<ConstructorAttr>() 3567 && !NewFD->hasAttr<DestructorAttr>()) 3568 UnusedStaticFuncs.push_back(NewFD); 3569 3570 return NewFD; 3571} 3572 3573/// \brief Perform semantic checking of a new function declaration. 3574/// 3575/// Performs semantic analysis of the new function declaration 3576/// NewFD. This routine performs all semantic checking that does not 3577/// require the actual declarator involved in the declaration, and is 3578/// used both for the declaration of functions as they are parsed 3579/// (called via ActOnDeclarator) and for the declaration of functions 3580/// that have been instantiated via C++ template instantiation (called 3581/// via InstantiateDecl). 3582/// 3583/// \param IsExplicitSpecialiation whether this new function declaration is 3584/// an explicit specialization of the previous declaration. 3585/// 3586/// This sets NewFD->isInvalidDecl() to true if there was an error. 3587void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3588 LookupResult &Previous, 3589 bool IsExplicitSpecialization, 3590 bool &Redeclaration, 3591 bool &OverloadableAttrRequired) { 3592 // If NewFD is already known erroneous, don't do any of this checking. 3593 if (NewFD->isInvalidDecl()) 3594 return; 3595 3596 if (NewFD->getResultType()->isVariablyModifiedType()) { 3597 // Functions returning a variably modified type violate C99 6.7.5.2p2 3598 // because all functions have linkage. 3599 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3600 return NewFD->setInvalidDecl(); 3601 } 3602 3603 if (NewFD->isMain()) 3604 CheckMain(NewFD); 3605 3606 // Check for a previous declaration of this name. 3607 if (Previous.empty() && NewFD->isExternC()) { 3608 // Since we did not find anything by this name and we're declaring 3609 // an extern "C" function, look for a non-visible extern "C" 3610 // declaration with the same name. 3611 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3612 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3613 if (Pos != LocallyScopedExternalDecls.end()) 3614 Previous.addDecl(Pos->second); 3615 } 3616 3617 // Merge or overload the declaration with an existing declaration of 3618 // the same name, if appropriate. 3619 if (!Previous.empty()) { 3620 // Determine whether NewFD is an overload of PrevDecl or 3621 // a declaration that requires merging. If it's an overload, 3622 // there's no more work to do here; we'll just add the new 3623 // function to the scope. 3624 3625 NamedDecl *OldDecl = 0; 3626 if (!AllowOverloadingOfFunction(Previous, Context)) { 3627 Redeclaration = true; 3628 OldDecl = Previous.getFoundDecl(); 3629 } else { 3630 if (!getLangOptions().CPlusPlus) { 3631 OverloadableAttrRequired = true; 3632 3633 // Functions marked "overloadable" must have a prototype (that 3634 // we can't get through declaration merging). 3635 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3636 Diag(NewFD->getLocation(), 3637 diag::err_attribute_overloadable_no_prototype) 3638 << NewFD; 3639 Redeclaration = true; 3640 3641 // Turn this into a variadic function with no parameters. 3642 QualType R = Context.getFunctionType( 3643 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3644 0, 0, true, 0, false, false, 0, 0, 3645 FunctionType::ExtInfo()); 3646 NewFD->setType(R); 3647 return NewFD->setInvalidDecl(); 3648 } 3649 } 3650 3651 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3652 /*NewIsUsingDecl*/ false)) { 3653 case Ovl_Match: 3654 Redeclaration = true; 3655 break; 3656 3657 case Ovl_NonFunction: 3658 Redeclaration = true; 3659 break; 3660 3661 case Ovl_Overload: 3662 Redeclaration = false; 3663 break; 3664 } 3665 } 3666 3667 if (Redeclaration) { 3668 // NewFD and OldDecl represent declarations that need to be 3669 // merged. 3670 if (MergeFunctionDecl(NewFD, OldDecl)) 3671 return NewFD->setInvalidDecl(); 3672 3673 Previous.clear(); 3674 Previous.addDecl(OldDecl); 3675 3676 if (FunctionTemplateDecl *OldTemplateDecl 3677 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3678 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3679 FunctionTemplateDecl *NewTemplateDecl 3680 = NewFD->getDescribedFunctionTemplate(); 3681 assert(NewTemplateDecl && "Template/non-template mismatch"); 3682 if (CXXMethodDecl *Method 3683 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3684 Method->setAccess(OldTemplateDecl->getAccess()); 3685 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3686 } 3687 3688 // If this is an explicit specialization of a member that is a function 3689 // template, mark it as a member specialization. 3690 if (IsExplicitSpecialization && 3691 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3692 NewTemplateDecl->setMemberSpecialization(); 3693 assert(OldTemplateDecl->isMemberSpecialization()); 3694 } 3695 } else { 3696 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3697 NewFD->setAccess(OldDecl->getAccess()); 3698 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3699 } 3700 } 3701 } 3702 3703 // Semantic checking for this function declaration (in isolation). 3704 if (getLangOptions().CPlusPlus) { 3705 // C++-specific checks. 3706 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3707 CheckConstructor(Constructor); 3708 } else if (CXXDestructorDecl *Destructor = 3709 dyn_cast<CXXDestructorDecl>(NewFD)) { 3710 CXXRecordDecl *Record = Destructor->getParent(); 3711 QualType ClassType = Context.getTypeDeclType(Record); 3712 3713 // FIXME: Shouldn't we be able to perform this check even when the class 3714 // type is dependent? Both gcc and edg can handle that. 3715 if (!ClassType->isDependentType()) { 3716 DeclarationName Name 3717 = Context.DeclarationNames.getCXXDestructorName( 3718 Context.getCanonicalType(ClassType)); 3719 if (NewFD->getDeclName() != Name) { 3720 Diag(NewFD->getLocation(), diag::err_destructor_name); 3721 return NewFD->setInvalidDecl(); 3722 } 3723 } 3724 3725 Record->setUserDeclaredDestructor(true); 3726 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3727 // user-defined destructor. 3728 Record->setPOD(false); 3729 3730 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3731 // declared destructor. 3732 // FIXME: C++0x: don't do this for "= default" destructors 3733 Record->setHasTrivialDestructor(false); 3734 } else if (CXXConversionDecl *Conversion 3735 = dyn_cast<CXXConversionDecl>(NewFD)) { 3736 ActOnConversionDeclarator(Conversion); 3737 } 3738 3739 // Find any virtual functions that this function overrides. 3740 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3741 if (!Method->isFunctionTemplateSpecialization() && 3742 !Method->getDescribedFunctionTemplate()) 3743 AddOverriddenMethods(Method->getParent(), Method); 3744 } 3745 3746 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3747 if (NewFD->isOverloadedOperator() && 3748 CheckOverloadedOperatorDeclaration(NewFD)) 3749 return NewFD->setInvalidDecl(); 3750 3751 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3752 if (NewFD->getLiteralIdentifier() && 3753 CheckLiteralOperatorDeclaration(NewFD)) 3754 return NewFD->setInvalidDecl(); 3755 3756 // In C++, check default arguments now that we have merged decls. Unless 3757 // the lexical context is the class, because in this case this is done 3758 // during delayed parsing anyway. 3759 if (!CurContext->isRecord()) 3760 CheckCXXDefaultArguments(NewFD); 3761 } 3762} 3763 3764void Sema::CheckMain(FunctionDecl* FD) { 3765 // C++ [basic.start.main]p3: A program that declares main to be inline 3766 // or static is ill-formed. 3767 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3768 // shall not appear in a declaration of main. 3769 // static main is not an error under C99, but we should warn about it. 3770 bool isInline = FD->isInlineSpecified(); 3771 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3772 if (isInline || isStatic) { 3773 unsigned diagID = diag::warn_unusual_main_decl; 3774 if (isInline || getLangOptions().CPlusPlus) 3775 diagID = diag::err_unusual_main_decl; 3776 3777 int which = isStatic + (isInline << 1) - 1; 3778 Diag(FD->getLocation(), diagID) << which; 3779 } 3780 3781 QualType T = FD->getType(); 3782 assert(T->isFunctionType() && "function decl is not of function type"); 3783 const FunctionType* FT = T->getAs<FunctionType>(); 3784 3785 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3786 // TODO: add a replacement fixit to turn the return type into 'int'. 3787 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3788 FD->setInvalidDecl(true); 3789 } 3790 3791 // Treat protoless main() as nullary. 3792 if (isa<FunctionNoProtoType>(FT)) return; 3793 3794 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3795 unsigned nparams = FTP->getNumArgs(); 3796 assert(FD->getNumParams() == nparams); 3797 3798 bool HasExtraParameters = (nparams > 3); 3799 3800 // Darwin passes an undocumented fourth argument of type char**. If 3801 // other platforms start sprouting these, the logic below will start 3802 // getting shifty. 3803 if (nparams == 4 && 3804 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3805 HasExtraParameters = false; 3806 3807 if (HasExtraParameters) { 3808 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3809 FD->setInvalidDecl(true); 3810 nparams = 3; 3811 } 3812 3813 // FIXME: a lot of the following diagnostics would be improved 3814 // if we had some location information about types. 3815 3816 QualType CharPP = 3817 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3818 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3819 3820 for (unsigned i = 0; i < nparams; ++i) { 3821 QualType AT = FTP->getArgType(i); 3822 3823 bool mismatch = true; 3824 3825 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3826 mismatch = false; 3827 else if (Expected[i] == CharPP) { 3828 // As an extension, the following forms are okay: 3829 // char const ** 3830 // char const * const * 3831 // char * const * 3832 3833 QualifierCollector qs; 3834 const PointerType* PT; 3835 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3836 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3837 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3838 qs.removeConst(); 3839 mismatch = !qs.empty(); 3840 } 3841 } 3842 3843 if (mismatch) { 3844 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3845 // TODO: suggest replacing given type with expected type 3846 FD->setInvalidDecl(true); 3847 } 3848 } 3849 3850 if (nparams == 1 && !FD->isInvalidDecl()) { 3851 Diag(FD->getLocation(), diag::warn_main_one_arg); 3852 } 3853} 3854 3855bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3856 // FIXME: Need strict checking. In C89, we need to check for 3857 // any assignment, increment, decrement, function-calls, or 3858 // commas outside of a sizeof. In C99, it's the same list, 3859 // except that the aforementioned are allowed in unevaluated 3860 // expressions. Everything else falls under the 3861 // "may accept other forms of constant expressions" exception. 3862 // (We never end up here for C++, so the constant expression 3863 // rules there don't matter.) 3864 if (Init->isConstantInitializer(Context, false)) 3865 return false; 3866 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3867 << Init->getSourceRange(); 3868 return true; 3869} 3870 3871void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3872 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3873} 3874 3875/// AddInitializerToDecl - Adds the initializer Init to the 3876/// declaration dcl. If DirectInit is true, this is C++ direct 3877/// initialization rather than copy initialization. 3878void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3879 Decl *RealDecl = dcl.getAs<Decl>(); 3880 // If there is no declaration, there was an error parsing it. Just ignore 3881 // the initializer. 3882 if (RealDecl == 0) 3883 return; 3884 3885 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3886 // With declarators parsed the way they are, the parser cannot 3887 // distinguish between a normal initializer and a pure-specifier. 3888 // Thus this grotesque test. 3889 IntegerLiteral *IL; 3890 Expr *Init = static_cast<Expr *>(init.get()); 3891 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3892 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3893 CheckPureMethod(Method, Init->getSourceRange()); 3894 else { 3895 Diag(Method->getLocation(), diag::err_member_function_initialization) 3896 << Method->getDeclName() << Init->getSourceRange(); 3897 Method->setInvalidDecl(); 3898 } 3899 return; 3900 } 3901 3902 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3903 if (!VDecl) { 3904 if (getLangOptions().CPlusPlus && 3905 RealDecl->getLexicalDeclContext()->isRecord() && 3906 isa<NamedDecl>(RealDecl)) 3907 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3908 << cast<NamedDecl>(RealDecl)->getDeclName(); 3909 else 3910 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3911 RealDecl->setInvalidDecl(); 3912 return; 3913 } 3914 3915 // A definition must end up with a complete type, which means it must be 3916 // complete with the restriction that an array type might be completed by the 3917 // initializer; note that later code assumes this restriction. 3918 QualType BaseDeclType = VDecl->getType(); 3919 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3920 BaseDeclType = Array->getElementType(); 3921 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3922 diag::err_typecheck_decl_incomplete_type)) { 3923 RealDecl->setInvalidDecl(); 3924 return; 3925 } 3926 3927 // The variable can not have an abstract class type. 3928 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3929 diag::err_abstract_type_in_decl, 3930 AbstractVariableType)) 3931 VDecl->setInvalidDecl(); 3932 3933 const VarDecl *Def; 3934 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3935 Diag(VDecl->getLocation(), diag::err_redefinition) 3936 << VDecl->getDeclName(); 3937 Diag(Def->getLocation(), diag::note_previous_definition); 3938 VDecl->setInvalidDecl(); 3939 return; 3940 } 3941 3942 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 3943 setFunctionHasBranchProtectedScope(); 3944 3945 // Take ownership of the expression, now that we're sure we have somewhere 3946 // to put it. 3947 Expr *Init = init.takeAs<Expr>(); 3948 assert(Init && "missing initializer"); 3949 3950 // Capture the variable that is being initialized and the style of 3951 // initialization. 3952 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3953 3954 // FIXME: Poor source location information. 3955 InitializationKind Kind 3956 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3957 Init->getLocStart(), 3958 Init->getLocEnd()) 3959 : InitializationKind::CreateCopy(VDecl->getLocation(), 3960 Init->getLocStart()); 3961 3962 // Get the decls type and save a reference for later, since 3963 // CheckInitializerTypes may change it. 3964 QualType DclT = VDecl->getType(), SavT = DclT; 3965 if (VDecl->isBlockVarDecl()) { 3966 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3967 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3968 VDecl->setInvalidDecl(); 3969 } else if (!VDecl->isInvalidDecl()) { 3970 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3971 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3972 MultiExprArg(*this, (void**)&Init, 1), 3973 &DclT); 3974 if (Result.isInvalid()) { 3975 VDecl->setInvalidDecl(); 3976 return; 3977 } 3978 3979 Init = Result.takeAs<Expr>(); 3980 3981 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3982 // Don't check invalid declarations to avoid emitting useless diagnostics. 3983 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3984 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3985 CheckForConstantInitializer(Init, DclT); 3986 } 3987 } 3988 } else if (VDecl->isStaticDataMember() && 3989 VDecl->getLexicalDeclContext()->isRecord()) { 3990 // This is an in-class initialization for a static data member, e.g., 3991 // 3992 // struct S { 3993 // static const int value = 17; 3994 // }; 3995 3996 // Attach the initializer 3997 VDecl->setInit(Init); 3998 3999 // C++ [class.mem]p4: 4000 // A member-declarator can contain a constant-initializer only 4001 // if it declares a static member (9.4) of const integral or 4002 // const enumeration type, see 9.4.2. 4003 QualType T = VDecl->getType(); 4004 if (!T->isDependentType() && 4005 (!Context.getCanonicalType(T).isConstQualified() || 4006 !T->isIntegralOrEnumerationType())) { 4007 Diag(VDecl->getLocation(), diag::err_member_initialization) 4008 << VDecl->getDeclName() << Init->getSourceRange(); 4009 VDecl->setInvalidDecl(); 4010 } else { 4011 // C++ [class.static.data]p4: 4012 // If a static data member is of const integral or const 4013 // enumeration type, its declaration in the class definition 4014 // can specify a constant-initializer which shall be an 4015 // integral constant expression (5.19). 4016 if (!Init->isTypeDependent() && 4017 !Init->getType()->isIntegralOrEnumerationType()) { 4018 // We have a non-dependent, non-integral or enumeration type. 4019 Diag(Init->getSourceRange().getBegin(), 4020 diag::err_in_class_initializer_non_integral_type) 4021 << Init->getType() << Init->getSourceRange(); 4022 VDecl->setInvalidDecl(); 4023 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 4024 // Check whether the expression is a constant expression. 4025 llvm::APSInt Value; 4026 SourceLocation Loc; 4027 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4028 Diag(Loc, diag::err_in_class_initializer_non_constant) 4029 << Init->getSourceRange(); 4030 VDecl->setInvalidDecl(); 4031 } else if (!VDecl->getType()->isDependentType()) 4032 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 4033 } 4034 } 4035 } else if (VDecl->isFileVarDecl()) { 4036 if (VDecl->getStorageClass() == VarDecl::Extern && 4037 (!getLangOptions().CPlusPlus || 4038 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4039 Diag(VDecl->getLocation(), diag::warn_extern_init); 4040 if (!VDecl->isInvalidDecl()) { 4041 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4042 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4043 MultiExprArg(*this, (void**)&Init, 1), 4044 &DclT); 4045 if (Result.isInvalid()) { 4046 VDecl->setInvalidDecl(); 4047 return; 4048 } 4049 4050 Init = Result.takeAs<Expr>(); 4051 } 4052 4053 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4054 // Don't check invalid declarations to avoid emitting useless diagnostics. 4055 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4056 // C99 6.7.8p4. All file scoped initializers need to be constant. 4057 CheckForConstantInitializer(Init, DclT); 4058 } 4059 } 4060 // If the type changed, it means we had an incomplete type that was 4061 // completed by the initializer. For example: 4062 // int ary[] = { 1, 3, 5 }; 4063 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4064 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4065 VDecl->setType(DclT); 4066 Init->setType(DclT); 4067 } 4068 4069 Init = MaybeCreateCXXExprWithTemporaries(Init); 4070 // Attach the initializer to the decl. 4071 VDecl->setInit(Init); 4072 4073 if (getLangOptions().CPlusPlus) { 4074 if (!VDecl->isInvalidDecl() && 4075 !VDecl->getDeclContext()->isDependentContext() && 4076 VDecl->hasGlobalStorage() && 4077 !Init->isConstantInitializer(Context, 4078 VDecl->getType()->isReferenceType())) 4079 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4080 << Init->getSourceRange(); 4081 4082 // Make sure we mark the destructor as used if necessary. 4083 QualType InitType = VDecl->getType(); 4084 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4085 InitType = Context.getBaseElementType(Array); 4086 if (const RecordType *Record = InitType->getAs<RecordType>()) 4087 FinalizeVarWithDestructor(VDecl, Record); 4088 } 4089 4090 return; 4091} 4092 4093/// ActOnInitializerError - Given that there was an error parsing an 4094/// initializer for the given declaration, try to return to some form 4095/// of sanity. 4096void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4097 // Our main concern here is re-establishing invariants like "a 4098 // variable's type is either dependent or complete". 4099 Decl *D = dcl.getAs<Decl>(); 4100 if (!D || D->isInvalidDecl()) return; 4101 4102 VarDecl *VD = dyn_cast<VarDecl>(D); 4103 if (!VD) return; 4104 4105 QualType Ty = VD->getType(); 4106 if (Ty->isDependentType()) return; 4107 4108 // Require a complete type. 4109 if (RequireCompleteType(VD->getLocation(), 4110 Context.getBaseElementType(Ty), 4111 diag::err_typecheck_decl_incomplete_type)) { 4112 VD->setInvalidDecl(); 4113 return; 4114 } 4115 4116 // Require an abstract type. 4117 if (RequireNonAbstractType(VD->getLocation(), Ty, 4118 diag::err_abstract_type_in_decl, 4119 AbstractVariableType)) { 4120 VD->setInvalidDecl(); 4121 return; 4122 } 4123 4124 // Don't bother complaining about constructors or destructors, 4125 // though. 4126} 4127 4128void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4129 bool TypeContainsUndeducedAuto) { 4130 Decl *RealDecl = dcl.getAs<Decl>(); 4131 4132 // If there is no declaration, there was an error parsing it. Just ignore it. 4133 if (RealDecl == 0) 4134 return; 4135 4136 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4137 QualType Type = Var->getType(); 4138 4139 // C++0x [dcl.spec.auto]p3 4140 if (TypeContainsUndeducedAuto) { 4141 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4142 << Var->getDeclName() << Type; 4143 Var->setInvalidDecl(); 4144 return; 4145 } 4146 4147 switch (Var->isThisDeclarationADefinition()) { 4148 case VarDecl::Definition: 4149 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4150 break; 4151 4152 // We have an out-of-line definition of a static data member 4153 // that has an in-class initializer, so we type-check this like 4154 // a declaration. 4155 // 4156 // Fall through 4157 4158 case VarDecl::DeclarationOnly: 4159 // It's only a declaration. 4160 4161 // Block scope. C99 6.7p7: If an identifier for an object is 4162 // declared with no linkage (C99 6.2.2p6), the type for the 4163 // object shall be complete. 4164 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4165 !Var->getLinkage() && !Var->isInvalidDecl() && 4166 RequireCompleteType(Var->getLocation(), Type, 4167 diag::err_typecheck_decl_incomplete_type)) 4168 Var->setInvalidDecl(); 4169 4170 // Make sure that the type is not abstract. 4171 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4172 RequireNonAbstractType(Var->getLocation(), Type, 4173 diag::err_abstract_type_in_decl, 4174 AbstractVariableType)) 4175 Var->setInvalidDecl(); 4176 return; 4177 4178 case VarDecl::TentativeDefinition: 4179 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4180 // object that has file scope without an initializer, and without a 4181 // storage-class specifier or with the storage-class specifier "static", 4182 // constitutes a tentative definition. Note: A tentative definition with 4183 // external linkage is valid (C99 6.2.2p5). 4184 if (!Var->isInvalidDecl()) { 4185 if (const IncompleteArrayType *ArrayT 4186 = Context.getAsIncompleteArrayType(Type)) { 4187 if (RequireCompleteType(Var->getLocation(), 4188 ArrayT->getElementType(), 4189 diag::err_illegal_decl_array_incomplete_type)) 4190 Var->setInvalidDecl(); 4191 } else if (Var->getStorageClass() == VarDecl::Static) { 4192 // C99 6.9.2p3: If the declaration of an identifier for an object is 4193 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4194 // declared type shall not be an incomplete type. 4195 // NOTE: code such as the following 4196 // static struct s; 4197 // struct s { int a; }; 4198 // is accepted by gcc. Hence here we issue a warning instead of 4199 // an error and we do not invalidate the static declaration. 4200 // NOTE: to avoid multiple warnings, only check the first declaration. 4201 if (Var->getPreviousDeclaration() == 0) 4202 RequireCompleteType(Var->getLocation(), Type, 4203 diag::ext_typecheck_decl_incomplete_type); 4204 } 4205 } 4206 4207 // Record the tentative definition; we're done. 4208 if (!Var->isInvalidDecl()) 4209 TentativeDefinitions.push_back(Var); 4210 return; 4211 } 4212 4213 // Provide a specific diagnostic for uninitialized variable 4214 // definitions with incomplete array type. 4215 if (Type->isIncompleteArrayType()) { 4216 Diag(Var->getLocation(), 4217 diag::err_typecheck_incomplete_array_needs_initializer); 4218 Var->setInvalidDecl(); 4219 return; 4220 } 4221 4222 // Provide a specific diagnostic for uninitialized variable 4223 // definitions with reference type. 4224 if (Type->isReferenceType()) { 4225 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4226 << Var->getDeclName() 4227 << SourceRange(Var->getLocation(), Var->getLocation()); 4228 Var->setInvalidDecl(); 4229 return; 4230 } 4231 4232 // Do not attempt to type-check the default initializer for a 4233 // variable with dependent type. 4234 if (Type->isDependentType()) 4235 return; 4236 4237 if (Var->isInvalidDecl()) 4238 return; 4239 4240 if (RequireCompleteType(Var->getLocation(), 4241 Context.getBaseElementType(Type), 4242 diag::err_typecheck_decl_incomplete_type)) { 4243 Var->setInvalidDecl(); 4244 return; 4245 } 4246 4247 // The variable can not have an abstract class type. 4248 if (RequireNonAbstractType(Var->getLocation(), Type, 4249 diag::err_abstract_type_in_decl, 4250 AbstractVariableType)) { 4251 Var->setInvalidDecl(); 4252 return; 4253 } 4254 4255 const RecordType *Record 4256 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4257 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4258 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4259 // C++03 [dcl.init]p9: 4260 // If no initializer is specified for an object, and the 4261 // object is of (possibly cv-qualified) non-POD class type (or 4262 // array thereof), the object shall be default-initialized; if 4263 // the object is of const-qualified type, the underlying class 4264 // type shall have a user-declared default 4265 // constructor. Otherwise, if no initializer is specified for 4266 // a non- static object, the object and its subobjects, if 4267 // any, have an indeterminate initial value); if the object 4268 // or any of its subobjects are of const-qualified type, the 4269 // program is ill-formed. 4270 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4271 } else { 4272 // Check for jumps past the implicit initializer. C++0x 4273 // clarifies that this applies to a "variable with automatic 4274 // storage duration", not a "local variable". 4275 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4276 setFunctionHasBranchProtectedScope(); 4277 4278 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4279 InitializationKind Kind 4280 = InitializationKind::CreateDefault(Var->getLocation()); 4281 4282 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4283 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4284 MultiExprArg(*this, 0, 0)); 4285 if (Init.isInvalid()) 4286 Var->setInvalidDecl(); 4287 else if (Init.get()) { 4288 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4289 4290 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4291 Var->hasGlobalStorage() && 4292 !Var->getDeclContext()->isDependentContext() && 4293 !Var->getInit()->isConstantInitializer(Context, false)) 4294 Diag(Var->getLocation(), diag::warn_global_constructor); 4295 } 4296 } 4297 4298 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4299 FinalizeVarWithDestructor(Var, Record); 4300 } 4301} 4302 4303Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4304 DeclPtrTy *Group, 4305 unsigned NumDecls) { 4306 llvm::SmallVector<Decl*, 8> Decls; 4307 4308 if (DS.isTypeSpecOwned()) 4309 Decls.push_back((Decl*)DS.getTypeRep()); 4310 4311 for (unsigned i = 0; i != NumDecls; ++i) 4312 if (Decl *D = Group[i].getAs<Decl>()) 4313 Decls.push_back(D); 4314 4315 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4316 Decls.data(), Decls.size())); 4317} 4318 4319 4320/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4321/// to introduce parameters into function prototype scope. 4322Sema::DeclPtrTy 4323Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4324 const DeclSpec &DS = D.getDeclSpec(); 4325 4326 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4327 VarDecl::StorageClass StorageClass = VarDecl::None; 4328 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4329 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4330 StorageClass = VarDecl::Register; 4331 StorageClassAsWritten = VarDecl::Register; 4332 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4333 Diag(DS.getStorageClassSpecLoc(), 4334 diag::err_invalid_storage_class_in_func_decl); 4335 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4336 } 4337 4338 if (D.getDeclSpec().isThreadSpecified()) 4339 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4340 4341 DiagnoseFunctionSpecifiers(D); 4342 4343 // Check that there are no default arguments inside the type of this 4344 // parameter (C++ only). 4345 if (getLangOptions().CPlusPlus) 4346 CheckExtraCXXDefaultArguments(D); 4347 4348 TagDecl *OwnedDecl = 0; 4349 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4350 QualType parmDeclType = TInfo->getType(); 4351 4352 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4353 // C++ [dcl.fct]p6: 4354 // Types shall not be defined in return or parameter types. 4355 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4356 << Context.getTypeDeclType(OwnedDecl); 4357 } 4358 4359 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4360 IdentifierInfo *II = D.getIdentifier(); 4361 if (II) { 4362 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4363 ForRedeclaration); 4364 LookupName(R, S); 4365 if (R.isSingleResult()) { 4366 NamedDecl *PrevDecl = R.getFoundDecl(); 4367 if (PrevDecl->isTemplateParameter()) { 4368 // Maybe we will complain about the shadowed template parameter. 4369 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4370 // Just pretend that we didn't see the previous declaration. 4371 PrevDecl = 0; 4372 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4373 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4374 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4375 4376 // Recover by removing the name 4377 II = 0; 4378 D.SetIdentifier(0, D.getIdentifierLoc()); 4379 D.setInvalidType(true); 4380 } 4381 } 4382 } 4383 4384 // Temporarily put parameter variables in the translation unit, not 4385 // the enclosing context. This prevents them from accidentally 4386 // looking like class members in C++. 4387 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4388 TInfo, parmDeclType, II, 4389 D.getIdentifierLoc(), 4390 StorageClass, StorageClassAsWritten); 4391 4392 if (D.isInvalidType()) 4393 New->setInvalidDecl(); 4394 4395 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4396 if (D.getCXXScopeSpec().isSet()) { 4397 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4398 << D.getCXXScopeSpec().getRange(); 4399 New->setInvalidDecl(); 4400 } 4401 4402 // Add the parameter declaration into this scope. 4403 S->AddDecl(DeclPtrTy::make(New)); 4404 if (II) 4405 IdResolver.AddDecl(New); 4406 4407 ProcessDeclAttributes(S, New, D); 4408 4409 if (New->hasAttr<BlocksAttr>()) { 4410 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4411 } 4412 return DeclPtrTy::make(New); 4413} 4414 4415/// \brief Synthesizes a variable for a parameter arising from a 4416/// typedef. 4417ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4418 SourceLocation Loc, 4419 QualType T) { 4420 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4421 T, Context.getTrivialTypeSourceInfo(T, Loc), 4422 VarDecl::None, VarDecl::None, 0); 4423 Param->setImplicit(); 4424 return Param; 4425} 4426 4427ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4428 TypeSourceInfo *TSInfo, QualType T, 4429 IdentifierInfo *Name, 4430 SourceLocation NameLoc, 4431 VarDecl::StorageClass StorageClass, 4432 VarDecl::StorageClass StorageClassAsWritten) { 4433 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4434 adjustParameterType(T), TSInfo, 4435 StorageClass, StorageClassAsWritten, 4436 0); 4437 4438 // Parameters can not be abstract class types. 4439 // For record types, this is done by the AbstractClassUsageDiagnoser once 4440 // the class has been completely parsed. 4441 if (!CurContext->isRecord() && 4442 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4443 AbstractParamType)) 4444 New->setInvalidDecl(); 4445 4446 // Parameter declarators cannot be interface types. All ObjC objects are 4447 // passed by reference. 4448 if (T->isObjCObjectType()) { 4449 Diag(NameLoc, 4450 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4451 New->setInvalidDecl(); 4452 } 4453 4454 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4455 // duration shall not be qualified by an address-space qualifier." 4456 // Since all parameters have automatic store duration, they can not have 4457 // an address space. 4458 if (T.getAddressSpace() != 0) { 4459 Diag(NameLoc, diag::err_arg_with_address_space); 4460 New->setInvalidDecl(); 4461 } 4462 4463 return New; 4464} 4465 4466void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4467 SourceLocation LocAfterDecls) { 4468 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4469 "Not a function declarator!"); 4470 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4471 4472 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4473 // for a K&R function. 4474 if (!FTI.hasPrototype) { 4475 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4476 --i; 4477 if (FTI.ArgInfo[i].Param == 0) { 4478 llvm::SmallString<256> Code; 4479 llvm::raw_svector_ostream(Code) << " int " 4480 << FTI.ArgInfo[i].Ident->getName() 4481 << ";\n"; 4482 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4483 << FTI.ArgInfo[i].Ident 4484 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4485 4486 // Implicitly declare the argument as type 'int' for lack of a better 4487 // type. 4488 DeclSpec DS; 4489 const char* PrevSpec; // unused 4490 unsigned DiagID; // unused 4491 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4492 PrevSpec, DiagID); 4493 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4494 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4495 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4496 } 4497 } 4498 } 4499} 4500 4501Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4502 Declarator &D) { 4503 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4504 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4505 "Not a function declarator!"); 4506 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4507 4508 if (FTI.hasPrototype) { 4509 // FIXME: Diagnose arguments without names in C. 4510 } 4511 4512 Scope *ParentScope = FnBodyScope->getParent(); 4513 4514 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4515 MultiTemplateParamsArg(*this), 4516 /*IsFunctionDefinition=*/true); 4517 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4518} 4519 4520static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4521 // Don't warn about invalid declarations. 4522 if (FD->isInvalidDecl()) 4523 return false; 4524 4525 // Or declarations that aren't global. 4526 if (!FD->isGlobal()) 4527 return false; 4528 4529 // Don't warn about C++ member functions. 4530 if (isa<CXXMethodDecl>(FD)) 4531 return false; 4532 4533 // Don't warn about 'main'. 4534 if (FD->isMain()) 4535 return false; 4536 4537 // Don't warn about inline functions. 4538 if (FD->isInlineSpecified()) 4539 return false; 4540 4541 // Don't warn about function templates. 4542 if (FD->getDescribedFunctionTemplate()) 4543 return false; 4544 4545 // Don't warn about function template specializations. 4546 if (FD->isFunctionTemplateSpecialization()) 4547 return false; 4548 4549 bool MissingPrototype = true; 4550 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4551 Prev; Prev = Prev->getPreviousDeclaration()) { 4552 // Ignore any declarations that occur in function or method 4553 // scope, because they aren't visible from the header. 4554 if (Prev->getDeclContext()->isFunctionOrMethod()) 4555 continue; 4556 4557 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4558 break; 4559 } 4560 4561 return MissingPrototype; 4562} 4563 4564Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4565 // Clear the last template instantiation error context. 4566 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4567 4568 if (!D) 4569 return D; 4570 FunctionDecl *FD = 0; 4571 4572 if (FunctionTemplateDecl *FunTmpl 4573 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4574 FD = FunTmpl->getTemplatedDecl(); 4575 else 4576 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4577 4578 // Enter a new function scope 4579 PushFunctionScope(); 4580 4581 // See if this is a redefinition. 4582 // But don't complain if we're in GNU89 mode and the previous definition 4583 // was an extern inline function. 4584 const FunctionDecl *Definition; 4585 if (FD->hasBody(Definition) && 4586 !canRedefineFunction(Definition, getLangOptions())) { 4587 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4588 Diag(Definition->getLocation(), diag::note_previous_definition); 4589 } 4590 4591 // Builtin functions cannot be defined. 4592 if (unsigned BuiltinID = FD->getBuiltinID()) { 4593 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4594 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4595 FD->setInvalidDecl(); 4596 } 4597 } 4598 4599 // The return type of a function definition must be complete 4600 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4601 QualType ResultType = FD->getResultType(); 4602 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4603 !FD->isInvalidDecl() && 4604 RequireCompleteType(FD->getLocation(), ResultType, 4605 diag::err_func_def_incomplete_result)) 4606 FD->setInvalidDecl(); 4607 4608 // GNU warning -Wmissing-prototypes: 4609 // Warn if a global function is defined without a previous 4610 // prototype declaration. This warning is issued even if the 4611 // definition itself provides a prototype. The aim is to detect 4612 // global functions that fail to be declared in header files. 4613 if (ShouldWarnAboutMissingPrototype(FD)) 4614 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4615 4616 if (FnBodyScope) 4617 PushDeclContext(FnBodyScope, FD); 4618 4619 // Check the validity of our function parameters 4620 CheckParmsForFunctionDef(FD); 4621 4622 bool ShouldCheckShadow = 4623 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4624 4625 // Introduce our parameters into the function scope 4626 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4627 ParmVarDecl *Param = FD->getParamDecl(p); 4628 Param->setOwningFunction(FD); 4629 4630 // If this has an identifier, add it to the scope stack. 4631 if (Param->getIdentifier() && FnBodyScope) { 4632 if (ShouldCheckShadow) 4633 CheckShadow(FnBodyScope, Param); 4634 4635 PushOnScopeChains(Param, FnBodyScope); 4636 } 4637 } 4638 4639 // Checking attributes of current function definition 4640 // dllimport attribute. 4641 if (FD->getAttr<DLLImportAttr>() && 4642 (!FD->getAttr<DLLExportAttr>())) { 4643 // dllimport attribute cannot be applied to definition. 4644 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4645 Diag(FD->getLocation(), 4646 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4647 << "dllimport"; 4648 FD->setInvalidDecl(); 4649 return DeclPtrTy::make(FD); 4650 } 4651 4652 // Visual C++ appears to not think this is an issue, so only issue 4653 // a warning when Microsoft extensions are disabled. 4654 if (!LangOpts.Microsoft) { 4655 // If a symbol previously declared dllimport is later defined, the 4656 // attribute is ignored in subsequent references, and a warning is 4657 // emitted. 4658 Diag(FD->getLocation(), 4659 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4660 << FD->getNameAsCString() << "dllimport"; 4661 } 4662 } 4663 return DeclPtrTy::make(FD); 4664} 4665 4666/// \brief Given the set of return statements within a function body, 4667/// compute the variables that are subject to the named return value 4668/// optimization. 4669/// 4670/// Each of the variables that is subject to the named return value 4671/// optimization will be marked as NRVO variables in the AST, and any 4672/// return statement that has a marked NRVO variable as its NRVO candidate can 4673/// use the named return value optimization. 4674/// 4675/// This function applies a very simplistic algorithm for NRVO: if every return 4676/// statement in the function has the same NRVO candidate, that candidate is 4677/// the NRVO variable. 4678/// 4679/// FIXME: Employ a smarter algorithm that accounts for multiple return 4680/// statements and the lifetimes of the NRVO candidates. We should be able to 4681/// find a maximal set of NRVO variables. 4682static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4683 const VarDecl *NRVOCandidate = 0; 4684 for (unsigned I = 0; I != NumReturns; ++I) { 4685 if (!Returns[I]->getNRVOCandidate()) 4686 return; 4687 4688 if (!NRVOCandidate) 4689 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4690 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4691 return; 4692 } 4693 4694 if (NRVOCandidate) 4695 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4696} 4697 4698Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4699 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4700} 4701 4702Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4703 bool IsInstantiation) { 4704 Decl *dcl = D.getAs<Decl>(); 4705 Stmt *Body = BodyArg.takeAs<Stmt>(); 4706 4707 FunctionDecl *FD = 0; 4708 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4709 if (FunTmpl) 4710 FD = FunTmpl->getTemplatedDecl(); 4711 else 4712 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4713 4714 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4715 4716 if (FD) { 4717 FD->setBody(Body); 4718 if (FD->isMain()) { 4719 // C and C++ allow for main to automagically return 0. 4720 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4721 FD->setHasImplicitReturnZero(true); 4722 WP.disableCheckFallThrough(); 4723 } 4724 4725 if (!FD->isInvalidDecl()) { 4726 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4727 4728 // If this is a constructor, we need a vtable. 4729 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4730 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4731 4732 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4733 FunctionScopes.back()->Returns.size()); 4734 } 4735 4736 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4737 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4738 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4739 MD->setBody(Body); 4740 MD->setEndLoc(Body->getLocEnd()); 4741 if (!MD->isInvalidDecl()) 4742 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4743 } else { 4744 return DeclPtrTy(); 4745 } 4746 4747 // Verify and clean out per-function state. 4748 4749 // Check goto/label use. 4750 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4751 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4752 LabelStmt *L = I->second; 4753 4754 // Verify that we have no forward references left. If so, there was a goto 4755 // or address of a label taken, but no definition of it. Label fwd 4756 // definitions are indicated with a null substmt. 4757 if (L->getSubStmt() != 0) 4758 continue; 4759 4760 // Emit error. 4761 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4762 4763 // At this point, we have gotos that use the bogus label. Stitch it into 4764 // the function body so that they aren't leaked and that the AST is well 4765 // formed. 4766 if (Body == 0) { 4767 // The whole function wasn't parsed correctly. 4768 continue; 4769 } 4770 4771 // Otherwise, the body is valid: we want to stitch the label decl into the 4772 // function somewhere so that it is properly owned and so that the goto 4773 // has a valid target. Do this by creating a new compound stmt with the 4774 // label in it. 4775 4776 // Give the label a sub-statement. 4777 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4778 4779 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4780 cast<CXXTryStmt>(Body)->getTryBlock() : 4781 cast<CompoundStmt>(Body); 4782 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4783 Compound->body_end()); 4784 Elements.push_back(L); 4785 Compound->setStmts(Context, Elements.data(), Elements.size()); 4786 } 4787 4788 if (Body) { 4789 // C++ constructors that have function-try-blocks can't have return 4790 // statements in the handlers of that block. (C++ [except.handle]p14) 4791 // Verify this. 4792 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4793 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4794 4795 // Verify that that gotos and switch cases don't jump into scopes illegally. 4796 // Verify that that gotos and switch cases don't jump into scopes illegally. 4797 if (FunctionNeedsScopeChecking() && 4798 !dcl->isInvalidDecl() && 4799 !hasAnyErrorsInThisFunction()) 4800 DiagnoseInvalidJumps(Body); 4801 4802 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 4803 if (!Destructor->getParent()->isDependentType()) 4804 CheckDestructor(Destructor); 4805 4806 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4807 Destructor->getParent()); 4808 } 4809 4810 // If any errors have occurred, clear out any temporaries that may have 4811 // been leftover. This ensures that these temporaries won't be picked up for 4812 // deletion in some later function. 4813 if (PP.getDiagnostics().hasErrorOccurred()) 4814 ExprTemporaries.clear(); 4815 else if (!isa<FunctionTemplateDecl>(dcl)) { 4816 // Since the body is valid, issue any analysis-based warnings that are 4817 // enabled. 4818 QualType ResultType; 4819 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4820 ResultType = FD->getResultType(); 4821 } 4822 else { 4823 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4824 ResultType = MD->getResultType(); 4825 } 4826 AnalysisWarnings.IssueWarnings(WP, dcl); 4827 } 4828 4829 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4830 } 4831 4832 if (!IsInstantiation) 4833 PopDeclContext(); 4834 4835 PopFunctionOrBlockScope(); 4836 4837 // If any errors have occurred, clear out any temporaries that may have 4838 // been leftover. This ensures that these temporaries won't be picked up for 4839 // deletion in some later function. 4840 if (getDiagnostics().hasErrorOccurred()) 4841 ExprTemporaries.clear(); 4842 4843 return D; 4844} 4845 4846/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4847/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4848NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4849 IdentifierInfo &II, Scope *S) { 4850 // Before we produce a declaration for an implicitly defined 4851 // function, see whether there was a locally-scoped declaration of 4852 // this name as a function or variable. If so, use that 4853 // (non-visible) declaration, and complain about it. 4854 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4855 = LocallyScopedExternalDecls.find(&II); 4856 if (Pos != LocallyScopedExternalDecls.end()) { 4857 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4858 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4859 return Pos->second; 4860 } 4861 4862 // Extension in C99. Legal in C90, but warn about it. 4863 if (II.getName().startswith("__builtin_")) 4864 Diag(Loc, diag::warn_builtin_unknown) << &II; 4865 else if (getLangOptions().C99) 4866 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4867 else 4868 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4869 4870 // Set a Declarator for the implicit definition: int foo(); 4871 const char *Dummy; 4872 DeclSpec DS; 4873 unsigned DiagID; 4874 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4875 Error = Error; // Silence warning. 4876 assert(!Error && "Error setting up implicit decl!"); 4877 Declarator D(DS, Declarator::BlockContext); 4878 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4879 0, 0, false, SourceLocation(), 4880 false, 0,0,0, Loc, Loc, D), 4881 SourceLocation()); 4882 D.SetIdentifier(&II, Loc); 4883 4884 // Insert this function into translation-unit scope. 4885 4886 DeclContext *PrevDC = CurContext; 4887 CurContext = Context.getTranslationUnitDecl(); 4888 4889 FunctionDecl *FD = 4890 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4891 FD->setImplicit(); 4892 4893 CurContext = PrevDC; 4894 4895 AddKnownFunctionAttributes(FD); 4896 4897 return FD; 4898} 4899 4900/// \brief Adds any function attributes that we know a priori based on 4901/// the declaration of this function. 4902/// 4903/// These attributes can apply both to implicitly-declared builtins 4904/// (like __builtin___printf_chk) or to library-declared functions 4905/// like NSLog or printf. 4906void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4907 if (FD->isInvalidDecl()) 4908 return; 4909 4910 // If this is a built-in function, map its builtin attributes to 4911 // actual attributes. 4912 if (unsigned BuiltinID = FD->getBuiltinID()) { 4913 // Handle printf-formatting attributes. 4914 unsigned FormatIdx; 4915 bool HasVAListArg; 4916 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4917 if (!FD->getAttr<FormatAttr>()) 4918 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4919 HasVAListArg ? 0 : FormatIdx+2)); 4920 } 4921 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 4922 HasVAListArg)) { 4923 if (!FD->getAttr<FormatAttr>()) 4924 FD->addAttr(::new (Context) FormatAttr(Context, "scanf", FormatIdx+1, 4925 HasVAListArg ? 0 : FormatIdx+2)); 4926 } 4927 4928 // Mark const if we don't care about errno and that is the only 4929 // thing preventing the function from being const. This allows 4930 // IRgen to use LLVM intrinsics for such functions. 4931 if (!getLangOptions().MathErrno && 4932 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4933 if (!FD->getAttr<ConstAttr>()) 4934 FD->addAttr(::new (Context) ConstAttr()); 4935 } 4936 4937 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4938 FD->setType(Context.getNoReturnType(FD->getType())); 4939 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4940 FD->addAttr(::new (Context) NoThrowAttr()); 4941 if (Context.BuiltinInfo.isConst(BuiltinID)) 4942 FD->addAttr(::new (Context) ConstAttr()); 4943 } 4944 4945 IdentifierInfo *Name = FD->getIdentifier(); 4946 if (!Name) 4947 return; 4948 if ((!getLangOptions().CPlusPlus && 4949 FD->getDeclContext()->isTranslationUnit()) || 4950 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4951 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4952 LinkageSpecDecl::lang_c)) { 4953 // Okay: this could be a libc/libm/Objective-C function we know 4954 // about. 4955 } else 4956 return; 4957 4958 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4959 // FIXME: NSLog and NSLogv should be target specific 4960 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4961 // FIXME: We known better than our headers. 4962 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4963 } else 4964 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4965 Name->isStr("NSLogv") ? 0 : 2)); 4966 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4967 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4968 // target-specific builtins, perhaps? 4969 if (!FD->getAttr<FormatAttr>()) 4970 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4971 Name->isStr("vasprintf") ? 0 : 3)); 4972 } 4973} 4974 4975TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4976 TypeSourceInfo *TInfo) { 4977 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4978 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4979 4980 if (!TInfo) { 4981 assert(D.isInvalidType() && "no declarator info for valid type"); 4982 TInfo = Context.getTrivialTypeSourceInfo(T); 4983 } 4984 4985 // Scope manipulation handled by caller. 4986 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4987 D.getIdentifierLoc(), 4988 D.getIdentifier(), 4989 TInfo); 4990 4991 if (const TagType *TT = T->getAs<TagType>()) { 4992 TagDecl *TD = TT->getDecl(); 4993 4994 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4995 // keep track of the TypedefDecl. 4996 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4997 TD->setTypedefForAnonDecl(NewTD); 4998 } 4999 5000 if (D.isInvalidType()) 5001 NewTD->setInvalidDecl(); 5002 return NewTD; 5003} 5004 5005 5006/// \brief Determine whether a tag with a given kind is acceptable 5007/// as a redeclaration of the given tag declaration. 5008/// 5009/// \returns true if the new tag kind is acceptable, false otherwise. 5010bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5011 TagTypeKind NewTag, 5012 SourceLocation NewTagLoc, 5013 const IdentifierInfo &Name) { 5014 // C++ [dcl.type.elab]p3: 5015 // The class-key or enum keyword present in the 5016 // elaborated-type-specifier shall agree in kind with the 5017 // declaration to which the name in the elaborated-type-specifier 5018 // refers. This rule also applies to the form of 5019 // elaborated-type-specifier that declares a class-name or 5020 // friend class since it can be construed as referring to the 5021 // definition of the class. Thus, in any 5022 // elaborated-type-specifier, the enum keyword shall be used to 5023 // refer to an enumeration (7.2), the union class-key shall be 5024 // used to refer to a union (clause 9), and either the class or 5025 // struct class-key shall be used to refer to a class (clause 9) 5026 // declared using the class or struct class-key. 5027 TagTypeKind OldTag = Previous->getTagKind(); 5028 if (OldTag == NewTag) 5029 return true; 5030 5031 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5032 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5033 // Warn about the struct/class tag mismatch. 5034 bool isTemplate = false; 5035 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5036 isTemplate = Record->getDescribedClassTemplate(); 5037 5038 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5039 << (NewTag == TTK_Class) 5040 << isTemplate << &Name 5041 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5042 OldTag == TTK_Class? "class" : "struct"); 5043 Diag(Previous->getLocation(), diag::note_previous_use); 5044 return true; 5045 } 5046 return false; 5047} 5048 5049/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5050/// former case, Name will be non-null. In the later case, Name will be null. 5051/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5052/// reference/declaration/definition of a tag. 5053Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5054 SourceLocation KWLoc, CXXScopeSpec &SS, 5055 IdentifierInfo *Name, SourceLocation NameLoc, 5056 AttributeList *Attr, AccessSpecifier AS, 5057 MultiTemplateParamsArg TemplateParameterLists, 5058 bool &OwnedDecl, bool &IsDependent) { 5059 // If this is not a definition, it must have a name. 5060 assert((Name != 0 || TUK == TUK_Definition) && 5061 "Nameless record must be a definition!"); 5062 5063 OwnedDecl = false; 5064 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5065 5066 // FIXME: Check explicit specializations more carefully. 5067 bool isExplicitSpecialization = false; 5068 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5069 bool Invalid = false; 5070 if (TUK != TUK_Reference) { 5071 if (TemplateParameterList *TemplateParams 5072 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5073 (TemplateParameterList**)TemplateParameterLists.get(), 5074 TemplateParameterLists.size(), 5075 TUK == TUK_Friend, 5076 isExplicitSpecialization, 5077 Invalid)) { 5078 // All but one template parameter lists have been matching. 5079 --NumMatchedTemplateParamLists; 5080 5081 if (TemplateParams->size() > 0) { 5082 // This is a declaration or definition of a class template (which may 5083 // be a member of another template). 5084 if (Invalid) 5085 return DeclPtrTy(); 5086 5087 OwnedDecl = false; 5088 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5089 SS, Name, NameLoc, Attr, 5090 TemplateParams, 5091 AS); 5092 TemplateParameterLists.release(); 5093 return Result.get(); 5094 } else { 5095 // The "template<>" header is extraneous. 5096 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5097 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5098 isExplicitSpecialization = true; 5099 } 5100 } 5101 } 5102 5103 DeclContext *SearchDC = CurContext; 5104 DeclContext *DC = CurContext; 5105 bool isStdBadAlloc = false; 5106 5107 RedeclarationKind Redecl = ForRedeclaration; 5108 if (TUK == TUK_Friend || TUK == TUK_Reference) 5109 Redecl = NotForRedeclaration; 5110 5111 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5112 5113 if (Name && SS.isNotEmpty()) { 5114 // We have a nested-name tag ('struct foo::bar'). 5115 5116 // Check for invalid 'foo::'. 5117 if (SS.isInvalid()) { 5118 Name = 0; 5119 goto CreateNewDecl; 5120 } 5121 5122 // If this is a friend or a reference to a class in a dependent 5123 // context, don't try to make a decl for it. 5124 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5125 DC = computeDeclContext(SS, false); 5126 if (!DC) { 5127 IsDependent = true; 5128 return DeclPtrTy(); 5129 } 5130 } else { 5131 DC = computeDeclContext(SS, true); 5132 if (!DC) { 5133 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5134 << SS.getRange(); 5135 return DeclPtrTy(); 5136 } 5137 } 5138 5139 if (RequireCompleteDeclContext(SS, DC)) 5140 return DeclPtrTy::make((Decl *)0); 5141 5142 SearchDC = DC; 5143 // Look-up name inside 'foo::'. 5144 LookupQualifiedName(Previous, DC); 5145 5146 if (Previous.isAmbiguous()) 5147 return DeclPtrTy(); 5148 5149 if (Previous.empty()) { 5150 // Name lookup did not find anything. However, if the 5151 // nested-name-specifier refers to the current instantiation, 5152 // and that current instantiation has any dependent base 5153 // classes, we might find something at instantiation time: treat 5154 // this as a dependent elaborated-type-specifier. 5155 if (Previous.wasNotFoundInCurrentInstantiation()) { 5156 IsDependent = true; 5157 return DeclPtrTy(); 5158 } 5159 5160 // A tag 'foo::bar' must already exist. 5161 Diag(NameLoc, diag::err_not_tag_in_scope) 5162 << Kind << Name << DC << SS.getRange(); 5163 Name = 0; 5164 Invalid = true; 5165 goto CreateNewDecl; 5166 } 5167 } else if (Name) { 5168 // If this is a named struct, check to see if there was a previous forward 5169 // declaration or definition. 5170 // FIXME: We're looking into outer scopes here, even when we 5171 // shouldn't be. Doing so can result in ambiguities that we 5172 // shouldn't be diagnosing. 5173 LookupName(Previous, S); 5174 5175 // Note: there used to be some attempt at recovery here. 5176 if (Previous.isAmbiguous()) 5177 return DeclPtrTy(); 5178 5179 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5180 // FIXME: This makes sure that we ignore the contexts associated 5181 // with C structs, unions, and enums when looking for a matching 5182 // tag declaration or definition. See the similar lookup tweak 5183 // in Sema::LookupName; is there a better way to deal with this? 5184 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5185 SearchDC = SearchDC->getParent(); 5186 } 5187 } 5188 5189 if (Previous.isSingleResult() && 5190 Previous.getFoundDecl()->isTemplateParameter()) { 5191 // Maybe we will complain about the shadowed template parameter. 5192 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5193 // Just pretend that we didn't see the previous declaration. 5194 Previous.clear(); 5195 } 5196 5197 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5198 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5199 // This is a declaration of or a reference to "std::bad_alloc". 5200 isStdBadAlloc = true; 5201 5202 if (Previous.empty() && StdBadAlloc) { 5203 // std::bad_alloc has been implicitly declared (but made invisible to 5204 // name lookup). Fill in this implicit declaration as the previous 5205 // declaration, so that the declarations get chained appropriately. 5206 Previous.addDecl(getStdBadAlloc()); 5207 } 5208 } 5209 5210 // If we didn't find a previous declaration, and this is a reference 5211 // (or friend reference), move to the correct scope. In C++, we 5212 // also need to do a redeclaration lookup there, just in case 5213 // there's a shadow friend decl. 5214 if (Name && Previous.empty() && 5215 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5216 if (Invalid) goto CreateNewDecl; 5217 assert(SS.isEmpty()); 5218 5219 if (TUK == TUK_Reference) { 5220 // C++ [basic.scope.pdecl]p5: 5221 // -- for an elaborated-type-specifier of the form 5222 // 5223 // class-key identifier 5224 // 5225 // if the elaborated-type-specifier is used in the 5226 // decl-specifier-seq or parameter-declaration-clause of a 5227 // function defined in namespace scope, the identifier is 5228 // declared as a class-name in the namespace that contains 5229 // the declaration; otherwise, except as a friend 5230 // declaration, the identifier is declared in the smallest 5231 // non-class, non-function-prototype scope that contains the 5232 // declaration. 5233 // 5234 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5235 // C structs and unions. 5236 // 5237 // It is an error in C++ to declare (rather than define) an enum 5238 // type, including via an elaborated type specifier. We'll 5239 // diagnose that later; for now, declare the enum in the same 5240 // scope as we would have picked for any other tag type. 5241 // 5242 // GNU C also supports this behavior as part of its incomplete 5243 // enum types extension, while GNU C++ does not. 5244 // 5245 // Find the context where we'll be declaring the tag. 5246 // FIXME: We would like to maintain the current DeclContext as the 5247 // lexical context, 5248 while (SearchDC->isRecord()) 5249 SearchDC = SearchDC->getParent(); 5250 5251 // Find the scope where we'll be declaring the tag. 5252 while (S->isClassScope() || 5253 (getLangOptions().CPlusPlus && 5254 S->isFunctionPrototypeScope()) || 5255 ((S->getFlags() & Scope::DeclScope) == 0) || 5256 (S->getEntity() && 5257 ((DeclContext *)S->getEntity())->isTransparentContext())) 5258 S = S->getParent(); 5259 } else { 5260 assert(TUK == TUK_Friend); 5261 // C++ [namespace.memdef]p3: 5262 // If a friend declaration in a non-local class first declares a 5263 // class or function, the friend class or function is a member of 5264 // the innermost enclosing namespace. 5265 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5266 } 5267 5268 // In C++, we need to do a redeclaration lookup to properly 5269 // diagnose some problems. 5270 if (getLangOptions().CPlusPlus) { 5271 Previous.setRedeclarationKind(ForRedeclaration); 5272 LookupQualifiedName(Previous, SearchDC); 5273 } 5274 } 5275 5276 if (!Previous.empty()) { 5277 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5278 5279 // It's okay to have a tag decl in the same scope as a typedef 5280 // which hides a tag decl in the same scope. Finding this 5281 // insanity with a redeclaration lookup can only actually happen 5282 // in C++. 5283 // 5284 // This is also okay for elaborated-type-specifiers, which is 5285 // technically forbidden by the current standard but which is 5286 // okay according to the likely resolution of an open issue; 5287 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5288 if (getLangOptions().CPlusPlus) { 5289 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5290 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5291 TagDecl *Tag = TT->getDecl(); 5292 if (Tag->getDeclName() == Name && 5293 Tag->getDeclContext()->getLookupContext() 5294 ->Equals(TD->getDeclContext()->getLookupContext())) { 5295 PrevDecl = Tag; 5296 Previous.clear(); 5297 Previous.addDecl(Tag); 5298 } 5299 } 5300 } 5301 } 5302 5303 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5304 // If this is a use of a previous tag, or if the tag is already declared 5305 // in the same scope (so that the definition/declaration completes or 5306 // rementions the tag), reuse the decl. 5307 if (TUK == TUK_Reference || TUK == TUK_Friend || 5308 isDeclInScope(PrevDecl, SearchDC, S)) { 5309 // Make sure that this wasn't declared as an enum and now used as a 5310 // struct or something similar. 5311 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5312 bool SafeToContinue 5313 = (PrevTagDecl->getTagKind() != TTK_Enum && 5314 Kind != TTK_Enum); 5315 if (SafeToContinue) 5316 Diag(KWLoc, diag::err_use_with_wrong_tag) 5317 << Name 5318 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5319 PrevTagDecl->getKindName()); 5320 else 5321 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5322 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5323 5324 if (SafeToContinue) 5325 Kind = PrevTagDecl->getTagKind(); 5326 else { 5327 // Recover by making this an anonymous redefinition. 5328 Name = 0; 5329 Previous.clear(); 5330 Invalid = true; 5331 } 5332 } 5333 5334 if (!Invalid) { 5335 // If this is a use, just return the declaration we found. 5336 5337 // FIXME: In the future, return a variant or some other clue 5338 // for the consumer of this Decl to know it doesn't own it. 5339 // For our current ASTs this shouldn't be a problem, but will 5340 // need to be changed with DeclGroups. 5341 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5342 TUK == TUK_Friend) 5343 return DeclPtrTy::make(PrevTagDecl); 5344 5345 // Diagnose attempts to redefine a tag. 5346 if (TUK == TUK_Definition) { 5347 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5348 // If we're defining a specialization and the previous definition 5349 // is from an implicit instantiation, don't emit an error 5350 // here; we'll catch this in the general case below. 5351 if (!isExplicitSpecialization || 5352 !isa<CXXRecordDecl>(Def) || 5353 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5354 == TSK_ExplicitSpecialization) { 5355 Diag(NameLoc, diag::err_redefinition) << Name; 5356 Diag(Def->getLocation(), diag::note_previous_definition); 5357 // If this is a redefinition, recover by making this 5358 // struct be anonymous, which will make any later 5359 // references get the previous definition. 5360 Name = 0; 5361 Previous.clear(); 5362 Invalid = true; 5363 } 5364 } else { 5365 // If the type is currently being defined, complain 5366 // about a nested redefinition. 5367 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5368 if (Tag->isBeingDefined()) { 5369 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5370 Diag(PrevTagDecl->getLocation(), 5371 diag::note_previous_definition); 5372 Name = 0; 5373 Previous.clear(); 5374 Invalid = true; 5375 } 5376 } 5377 5378 // Okay, this is definition of a previously declared or referenced 5379 // tag PrevDecl. We're going to create a new Decl for it. 5380 } 5381 } 5382 // If we get here we have (another) forward declaration or we 5383 // have a definition. Just create a new decl. 5384 5385 } else { 5386 // If we get here, this is a definition of a new tag type in a nested 5387 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5388 // new decl/type. We set PrevDecl to NULL so that the entities 5389 // have distinct types. 5390 Previous.clear(); 5391 } 5392 // If we get here, we're going to create a new Decl. If PrevDecl 5393 // is non-NULL, it's a definition of the tag declared by 5394 // PrevDecl. If it's NULL, we have a new definition. 5395 5396 5397 // Otherwise, PrevDecl is not a tag, but was found with tag 5398 // lookup. This is only actually possible in C++, where a few 5399 // things like templates still live in the tag namespace. 5400 } else { 5401 assert(getLangOptions().CPlusPlus); 5402 5403 // Use a better diagnostic if an elaborated-type-specifier 5404 // found the wrong kind of type on the first 5405 // (non-redeclaration) lookup. 5406 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5407 !Previous.isForRedeclaration()) { 5408 unsigned Kind = 0; 5409 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5410 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5411 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5412 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5413 Invalid = true; 5414 5415 // Otherwise, only diagnose if the declaration is in scope. 5416 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5417 // do nothing 5418 5419 // Diagnose implicit declarations introduced by elaborated types. 5420 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5421 unsigned Kind = 0; 5422 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5423 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5424 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5425 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5426 Invalid = true; 5427 5428 // Otherwise it's a declaration. Call out a particularly common 5429 // case here. 5430 } else if (isa<TypedefDecl>(PrevDecl)) { 5431 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5432 << Name 5433 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5434 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5435 Invalid = true; 5436 5437 // Otherwise, diagnose. 5438 } else { 5439 // The tag name clashes with something else in the target scope, 5440 // issue an error and recover by making this tag be anonymous. 5441 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5442 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5443 Name = 0; 5444 Invalid = true; 5445 } 5446 5447 // The existing declaration isn't relevant to us; we're in a 5448 // new scope, so clear out the previous declaration. 5449 Previous.clear(); 5450 } 5451 } 5452 5453CreateNewDecl: 5454 5455 TagDecl *PrevDecl = 0; 5456 if (Previous.isSingleResult()) 5457 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5458 5459 // If there is an identifier, use the location of the identifier as the 5460 // location of the decl, otherwise use the location of the struct/union 5461 // keyword. 5462 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5463 5464 // Otherwise, create a new declaration. If there is a previous 5465 // declaration of the same entity, the two will be linked via 5466 // PrevDecl. 5467 TagDecl *New; 5468 5469 if (Kind == TTK_Enum) { 5470 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5471 // enum X { A, B, C } D; D should chain to X. 5472 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5473 cast_or_null<EnumDecl>(PrevDecl)); 5474 // If this is an undefined enum, warn. 5475 if (TUK != TUK_Definition && !Invalid) { 5476 TagDecl *Def; 5477 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5478 Diag(Loc, diag::ext_forward_ref_enum_def) 5479 << New; 5480 Diag(Def->getLocation(), diag::note_previous_definition); 5481 } else { 5482 Diag(Loc, 5483 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5484 : diag::ext_forward_ref_enum); 5485 } 5486 } 5487 } else { 5488 // struct/union/class 5489 5490 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5491 // struct X { int A; } D; D should chain to X. 5492 if (getLangOptions().CPlusPlus) { 5493 // FIXME: Look for a way to use RecordDecl for simple structs. 5494 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5495 cast_or_null<CXXRecordDecl>(PrevDecl)); 5496 5497 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5498 StdBadAlloc = cast<CXXRecordDecl>(New); 5499 } else 5500 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5501 cast_or_null<RecordDecl>(PrevDecl)); 5502 } 5503 5504 // Maybe add qualifier info. 5505 if (SS.isNotEmpty()) { 5506 if (SS.isSet()) { 5507 NestedNameSpecifier *NNS 5508 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5509 New->setQualifierInfo(NNS, SS.getRange()); 5510 if (NumMatchedTemplateParamLists > 0) { 5511 New->setTemplateParameterListsInfo(Context, 5512 NumMatchedTemplateParamLists, 5513 (TemplateParameterList**) TemplateParameterLists.release()); 5514 } 5515 } 5516 else 5517 Invalid = true; 5518 } 5519 5520 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5521 // Add alignment attributes if necessary; these attributes are checked when 5522 // the ASTContext lays out the structure. 5523 // 5524 // It is important for implementing the correct semantics that this 5525 // happen here (in act on tag decl). The #pragma pack stack is 5526 // maintained as a result of parser callbacks which can occur at 5527 // many points during the parsing of a struct declaration (because 5528 // the #pragma tokens are effectively skipped over during the 5529 // parsing of the struct). 5530 AddAlignmentAttributesForRecord(RD); 5531 } 5532 5533 // If this is a specialization of a member class (of a class template), 5534 // check the specialization. 5535 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5536 Invalid = true; 5537 5538 if (Invalid) 5539 New->setInvalidDecl(); 5540 5541 if (Attr) 5542 ProcessDeclAttributeList(S, New, Attr); 5543 5544 // If we're declaring or defining a tag in function prototype scope 5545 // in C, note that this type can only be used within the function. 5546 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5547 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5548 5549 // Set the lexical context. If the tag has a C++ scope specifier, the 5550 // lexical context will be different from the semantic context. 5551 New->setLexicalDeclContext(CurContext); 5552 5553 // Mark this as a friend decl if applicable. 5554 if (TUK == TUK_Friend) 5555 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5556 5557 // Set the access specifier. 5558 if (!Invalid && SearchDC->isRecord()) 5559 SetMemberAccessSpecifier(New, PrevDecl, AS); 5560 5561 if (TUK == TUK_Definition) 5562 New->startDefinition(); 5563 5564 // If this has an identifier, add it to the scope stack. 5565 if (TUK == TUK_Friend) { 5566 // We might be replacing an existing declaration in the lookup tables; 5567 // if so, borrow its access specifier. 5568 if (PrevDecl) 5569 New->setAccess(PrevDecl->getAccess()); 5570 5571 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5572 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5573 if (Name) // can be null along some error paths 5574 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5575 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5576 } else if (Name) { 5577 S = getNonFieldDeclScope(S); 5578 PushOnScopeChains(New, S); 5579 } else { 5580 CurContext->addDecl(New); 5581 } 5582 5583 // If this is the C FILE type, notify the AST context. 5584 if (IdentifierInfo *II = New->getIdentifier()) 5585 if (!New->isInvalidDecl() && 5586 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5587 II->isStr("FILE")) 5588 Context.setFILEDecl(New); 5589 5590 OwnedDecl = true; 5591 return DeclPtrTy::make(New); 5592} 5593 5594void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5595 AdjustDeclIfTemplate(TagD); 5596 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5597 5598 // Enter the tag context. 5599 PushDeclContext(S, Tag); 5600} 5601 5602void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5603 SourceLocation LBraceLoc) { 5604 AdjustDeclIfTemplate(TagD); 5605 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5606 5607 FieldCollector->StartClass(); 5608 5609 if (!Record->getIdentifier()) 5610 return; 5611 5612 // C++ [class]p2: 5613 // [...] The class-name is also inserted into the scope of the 5614 // class itself; this is known as the injected-class-name. For 5615 // purposes of access checking, the injected-class-name is treated 5616 // as if it were a public member name. 5617 CXXRecordDecl *InjectedClassName 5618 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5619 CurContext, Record->getLocation(), 5620 Record->getIdentifier(), 5621 Record->getTagKeywordLoc(), 5622 Record); 5623 InjectedClassName->setImplicit(); 5624 InjectedClassName->setAccess(AS_public); 5625 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5626 InjectedClassName->setDescribedClassTemplate(Template); 5627 PushOnScopeChains(InjectedClassName, S); 5628 assert(InjectedClassName->isInjectedClassName() && 5629 "Broken injected-class-name"); 5630} 5631 5632void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5633 SourceLocation RBraceLoc) { 5634 AdjustDeclIfTemplate(TagD); 5635 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5636 Tag->setRBraceLoc(RBraceLoc); 5637 5638 if (isa<CXXRecordDecl>(Tag)) 5639 FieldCollector->FinishClass(); 5640 5641 // Exit this scope of this tag's definition. 5642 PopDeclContext(); 5643 5644 // Notify the consumer that we've defined a tag. 5645 Consumer.HandleTagDeclDefinition(Tag); 5646} 5647 5648void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5649 AdjustDeclIfTemplate(TagD); 5650 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5651 Tag->setInvalidDecl(); 5652 5653 // We're undoing ActOnTagStartDefinition here, not 5654 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5655 // the FieldCollector. 5656 5657 PopDeclContext(); 5658} 5659 5660// Note that FieldName may be null for anonymous bitfields. 5661bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5662 QualType FieldTy, const Expr *BitWidth, 5663 bool *ZeroWidth) { 5664 // Default to true; that shouldn't confuse checks for emptiness 5665 if (ZeroWidth) 5666 *ZeroWidth = true; 5667 5668 // C99 6.7.2.1p4 - verify the field type. 5669 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5670 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5671 // Handle incomplete types with specific error. 5672 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5673 return true; 5674 if (FieldName) 5675 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5676 << FieldName << FieldTy << BitWidth->getSourceRange(); 5677 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5678 << FieldTy << BitWidth->getSourceRange(); 5679 } 5680 5681 // If the bit-width is type- or value-dependent, don't try to check 5682 // it now. 5683 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5684 return false; 5685 5686 llvm::APSInt Value; 5687 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5688 return true; 5689 5690 if (Value != 0 && ZeroWidth) 5691 *ZeroWidth = false; 5692 5693 // Zero-width bitfield is ok for anonymous field. 5694 if (Value == 0 && FieldName) 5695 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5696 5697 if (Value.isSigned() && Value.isNegative()) { 5698 if (FieldName) 5699 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5700 << FieldName << Value.toString(10); 5701 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5702 << Value.toString(10); 5703 } 5704 5705 if (!FieldTy->isDependentType()) { 5706 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5707 if (Value.getZExtValue() > TypeSize) { 5708 if (!getLangOptions().CPlusPlus) { 5709 if (FieldName) 5710 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5711 << FieldName << (unsigned)Value.getZExtValue() 5712 << (unsigned)TypeSize; 5713 5714 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5715 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5716 } 5717 5718 if (FieldName) 5719 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5720 << FieldName << (unsigned)Value.getZExtValue() 5721 << (unsigned)TypeSize; 5722 else 5723 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5724 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5725 } 5726 } 5727 5728 return false; 5729} 5730 5731/// ActOnField - Each field of a struct/union/class is passed into this in order 5732/// to create a FieldDecl object for it. 5733Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5734 SourceLocation DeclStart, 5735 Declarator &D, ExprTy *BitfieldWidth) { 5736 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5737 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5738 AS_public); 5739 return DeclPtrTy::make(Res); 5740} 5741 5742/// HandleField - Analyze a field of a C struct or a C++ data member. 5743/// 5744FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5745 SourceLocation DeclStart, 5746 Declarator &D, Expr *BitWidth, 5747 AccessSpecifier AS) { 5748 IdentifierInfo *II = D.getIdentifier(); 5749 SourceLocation Loc = DeclStart; 5750 if (II) Loc = D.getIdentifierLoc(); 5751 5752 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5753 QualType T = TInfo->getType(); 5754 if (getLangOptions().CPlusPlus) 5755 CheckExtraCXXDefaultArguments(D); 5756 5757 DiagnoseFunctionSpecifiers(D); 5758 5759 if (D.getDeclSpec().isThreadSpecified()) 5760 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5761 5762 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5763 ForRedeclaration); 5764 5765 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5766 // Maybe we will complain about the shadowed template parameter. 5767 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5768 // Just pretend that we didn't see the previous declaration. 5769 PrevDecl = 0; 5770 } 5771 5772 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5773 PrevDecl = 0; 5774 5775 bool Mutable 5776 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5777 SourceLocation TSSL = D.getSourceRange().getBegin(); 5778 FieldDecl *NewFD 5779 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5780 AS, PrevDecl, &D); 5781 5782 if (NewFD->isInvalidDecl()) 5783 Record->setInvalidDecl(); 5784 5785 if (NewFD->isInvalidDecl() && PrevDecl) { 5786 // Don't introduce NewFD into scope; there's already something 5787 // with the same name in the same scope. 5788 } else if (II) { 5789 PushOnScopeChains(NewFD, S); 5790 } else 5791 Record->addDecl(NewFD); 5792 5793 return NewFD; 5794} 5795 5796/// \brief Build a new FieldDecl and check its well-formedness. 5797/// 5798/// This routine builds a new FieldDecl given the fields name, type, 5799/// record, etc. \p PrevDecl should refer to any previous declaration 5800/// with the same name and in the same scope as the field to be 5801/// created. 5802/// 5803/// \returns a new FieldDecl. 5804/// 5805/// \todo The Declarator argument is a hack. It will be removed once 5806FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5807 TypeSourceInfo *TInfo, 5808 RecordDecl *Record, SourceLocation Loc, 5809 bool Mutable, Expr *BitWidth, 5810 SourceLocation TSSL, 5811 AccessSpecifier AS, NamedDecl *PrevDecl, 5812 Declarator *D) { 5813 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5814 bool InvalidDecl = false; 5815 if (D) InvalidDecl = D->isInvalidType(); 5816 5817 // If we receive a broken type, recover by assuming 'int' and 5818 // marking this declaration as invalid. 5819 if (T.isNull()) { 5820 InvalidDecl = true; 5821 T = Context.IntTy; 5822 } 5823 5824 QualType EltTy = Context.getBaseElementType(T); 5825 if (!EltTy->isDependentType() && 5826 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5827 InvalidDecl = true; 5828 5829 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5830 // than a variably modified type. 5831 if (!InvalidDecl && T->isVariablyModifiedType()) { 5832 bool SizeIsNegative; 5833 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5834 SizeIsNegative); 5835 if (!FixedTy.isNull()) { 5836 Diag(Loc, diag::warn_illegal_constant_array_size); 5837 T = FixedTy; 5838 } else { 5839 if (SizeIsNegative) 5840 Diag(Loc, diag::err_typecheck_negative_array_size); 5841 else 5842 Diag(Loc, diag::err_typecheck_field_variable_size); 5843 InvalidDecl = true; 5844 } 5845 } 5846 5847 // Fields can not have abstract class types 5848 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5849 diag::err_abstract_type_in_decl, 5850 AbstractFieldType)) 5851 InvalidDecl = true; 5852 5853 bool ZeroWidth = false; 5854 // If this is declared as a bit-field, check the bit-field. 5855 if (!InvalidDecl && BitWidth && 5856 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5857 InvalidDecl = true; 5858 DeleteExpr(BitWidth); 5859 BitWidth = 0; 5860 ZeroWidth = false; 5861 } 5862 5863 // Check that 'mutable' is consistent with the type of the declaration. 5864 if (!InvalidDecl && Mutable) { 5865 unsigned DiagID = 0; 5866 if (T->isReferenceType()) 5867 DiagID = diag::err_mutable_reference; 5868 else if (T.isConstQualified()) 5869 DiagID = diag::err_mutable_const; 5870 5871 if (DiagID) { 5872 SourceLocation ErrLoc = Loc; 5873 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 5874 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 5875 Diag(ErrLoc, DiagID); 5876 Mutable = false; 5877 InvalidDecl = true; 5878 } 5879 } 5880 5881 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5882 BitWidth, Mutable); 5883 if (InvalidDecl) 5884 NewFD->setInvalidDecl(); 5885 5886 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5887 Diag(Loc, diag::err_duplicate_member) << II; 5888 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5889 NewFD->setInvalidDecl(); 5890 } 5891 5892 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5893 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5894 5895 if (!T->isPODType()) 5896 CXXRecord->setPOD(false); 5897 if (!ZeroWidth) 5898 CXXRecord->setEmpty(false); 5899 5900 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5901 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5902 if (RDecl->getDefinition()) { 5903 if (!RDecl->hasTrivialConstructor()) 5904 CXXRecord->setHasTrivialConstructor(false); 5905 if (!RDecl->hasTrivialCopyConstructor()) 5906 CXXRecord->setHasTrivialCopyConstructor(false); 5907 if (!RDecl->hasTrivialCopyAssignment()) 5908 CXXRecord->setHasTrivialCopyAssignment(false); 5909 if (!RDecl->hasTrivialDestructor()) 5910 CXXRecord->setHasTrivialDestructor(false); 5911 5912 // C++ 9.5p1: An object of a class with a non-trivial 5913 // constructor, a non-trivial copy constructor, a non-trivial 5914 // destructor, or a non-trivial copy assignment operator 5915 // cannot be a member of a union, nor can an array of such 5916 // objects. 5917 // TODO: C++0x alters this restriction significantly. 5918 if (Record->isUnion()) { 5919 // We check for copy constructors before constructors 5920 // because otherwise we'll never get complaints about 5921 // copy constructors. 5922 5923 CXXSpecialMember member = CXXInvalid; 5924 if (!RDecl->hasTrivialCopyConstructor()) 5925 member = CXXCopyConstructor; 5926 else if (!RDecl->hasTrivialConstructor()) 5927 member = CXXConstructor; 5928 else if (!RDecl->hasTrivialCopyAssignment()) 5929 member = CXXCopyAssignment; 5930 else if (!RDecl->hasTrivialDestructor()) 5931 member = CXXDestructor; 5932 5933 if (member != CXXInvalid) { 5934 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5935 DiagnoseNontrivial(RT, member); 5936 NewFD->setInvalidDecl(); 5937 } 5938 } 5939 } 5940 } 5941 } 5942 5943 // FIXME: We need to pass in the attributes given an AST 5944 // representation, not a parser representation. 5945 if (D) 5946 // FIXME: What to pass instead of TUScope? 5947 ProcessDeclAttributes(TUScope, NewFD, *D); 5948 5949 if (T.isObjCGCWeak()) 5950 Diag(Loc, diag::warn_attribute_weak_on_field); 5951 5952 NewFD->setAccess(AS); 5953 5954 // C++ [dcl.init.aggr]p1: 5955 // An aggregate is an array or a class (clause 9) with [...] no 5956 // private or protected non-static data members (clause 11). 5957 // A POD must be an aggregate. 5958 if (getLangOptions().CPlusPlus && 5959 (AS == AS_private || AS == AS_protected)) { 5960 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5961 CXXRecord->setAggregate(false); 5962 CXXRecord->setPOD(false); 5963 } 5964 5965 return NewFD; 5966} 5967 5968/// DiagnoseNontrivial - Given that a class has a non-trivial 5969/// special member, figure out why. 5970void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5971 QualType QT(T, 0U); 5972 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5973 5974 // Check whether the member was user-declared. 5975 switch (member) { 5976 case CXXInvalid: 5977 break; 5978 5979 case CXXConstructor: 5980 if (RD->hasUserDeclaredConstructor()) { 5981 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5982 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5983 const FunctionDecl *body = 0; 5984 ci->hasBody(body); 5985 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5986 SourceLocation CtorLoc = ci->getLocation(); 5987 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5988 return; 5989 } 5990 } 5991 5992 assert(0 && "found no user-declared constructors"); 5993 return; 5994 } 5995 break; 5996 5997 case CXXCopyConstructor: 5998 if (RD->hasUserDeclaredCopyConstructor()) { 5999 SourceLocation CtorLoc = 6000 RD->getCopyConstructor(Context, 0)->getLocation(); 6001 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6002 return; 6003 } 6004 break; 6005 6006 case CXXCopyAssignment: 6007 if (RD->hasUserDeclaredCopyAssignment()) { 6008 // FIXME: this should use the location of the copy 6009 // assignment, not the type. 6010 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6011 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6012 return; 6013 } 6014 break; 6015 6016 case CXXDestructor: 6017 if (RD->hasUserDeclaredDestructor()) { 6018 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6019 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6020 return; 6021 } 6022 break; 6023 } 6024 6025 typedef CXXRecordDecl::base_class_iterator base_iter; 6026 6027 // Virtual bases and members inhibit trivial copying/construction, 6028 // but not trivial destruction. 6029 if (member != CXXDestructor) { 6030 // Check for virtual bases. vbases includes indirect virtual bases, 6031 // so we just iterate through the direct bases. 6032 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6033 if (bi->isVirtual()) { 6034 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6035 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6036 return; 6037 } 6038 6039 // Check for virtual methods. 6040 typedef CXXRecordDecl::method_iterator meth_iter; 6041 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6042 ++mi) { 6043 if (mi->isVirtual()) { 6044 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6045 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6046 return; 6047 } 6048 } 6049 } 6050 6051 bool (CXXRecordDecl::*hasTrivial)() const; 6052 switch (member) { 6053 case CXXConstructor: 6054 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6055 case CXXCopyConstructor: 6056 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6057 case CXXCopyAssignment: 6058 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6059 case CXXDestructor: 6060 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6061 default: 6062 assert(0 && "unexpected special member"); return; 6063 } 6064 6065 // Check for nontrivial bases (and recurse). 6066 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6067 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6068 assert(BaseRT && "Don't know how to handle dependent bases"); 6069 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6070 if (!(BaseRecTy->*hasTrivial)()) { 6071 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6072 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6073 DiagnoseNontrivial(BaseRT, member); 6074 return; 6075 } 6076 } 6077 6078 // Check for nontrivial members (and recurse). 6079 typedef RecordDecl::field_iterator field_iter; 6080 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6081 ++fi) { 6082 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6083 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6084 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6085 6086 if (!(EltRD->*hasTrivial)()) { 6087 SourceLocation FLoc = (*fi)->getLocation(); 6088 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6089 DiagnoseNontrivial(EltRT, member); 6090 return; 6091 } 6092 } 6093 } 6094 6095 assert(0 && "found no explanation for non-trivial member"); 6096} 6097 6098/// TranslateIvarVisibility - Translate visibility from a token ID to an 6099/// AST enum value. 6100static ObjCIvarDecl::AccessControl 6101TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6102 switch (ivarVisibility) { 6103 default: assert(0 && "Unknown visitibility kind"); 6104 case tok::objc_private: return ObjCIvarDecl::Private; 6105 case tok::objc_public: return ObjCIvarDecl::Public; 6106 case tok::objc_protected: return ObjCIvarDecl::Protected; 6107 case tok::objc_package: return ObjCIvarDecl::Package; 6108 } 6109} 6110 6111/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6112/// in order to create an IvarDecl object for it. 6113Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6114 SourceLocation DeclStart, 6115 DeclPtrTy IntfDecl, 6116 Declarator &D, ExprTy *BitfieldWidth, 6117 tok::ObjCKeywordKind Visibility) { 6118 6119 IdentifierInfo *II = D.getIdentifier(); 6120 Expr *BitWidth = (Expr*)BitfieldWidth; 6121 SourceLocation Loc = DeclStart; 6122 if (II) Loc = D.getIdentifierLoc(); 6123 6124 // FIXME: Unnamed fields can be handled in various different ways, for 6125 // example, unnamed unions inject all members into the struct namespace! 6126 6127 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6128 QualType T = TInfo->getType(); 6129 6130 if (BitWidth) { 6131 // 6.7.2.1p3, 6.7.2.1p4 6132 if (VerifyBitField(Loc, II, T, BitWidth)) { 6133 D.setInvalidType(); 6134 DeleteExpr(BitWidth); 6135 BitWidth = 0; 6136 } 6137 } else { 6138 // Not a bitfield. 6139 6140 // validate II. 6141 6142 } 6143 if (T->isReferenceType()) { 6144 Diag(Loc, diag::err_ivar_reference_type); 6145 D.setInvalidType(); 6146 } 6147 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6148 // than a variably modified type. 6149 else if (T->isVariablyModifiedType()) { 6150 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6151 D.setInvalidType(); 6152 } 6153 6154 // Get the visibility (access control) for this ivar. 6155 ObjCIvarDecl::AccessControl ac = 6156 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6157 : ObjCIvarDecl::None; 6158 // Must set ivar's DeclContext to its enclosing interface. 6159 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6160 ObjCContainerDecl *EnclosingContext; 6161 if (ObjCImplementationDecl *IMPDecl = 6162 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6163 // Case of ivar declared in an implementation. Context is that of its class. 6164 EnclosingContext = IMPDecl->getClassInterface(); 6165 assert(EnclosingContext && "Implementation has no class interface!"); 6166 } else { 6167 if (ObjCCategoryDecl *CDecl = 6168 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6169 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6170 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6171 return DeclPtrTy(); 6172 } 6173 } 6174 EnclosingContext = EnclosingDecl; 6175 } 6176 6177 // Construct the decl. 6178 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6179 EnclosingContext, Loc, II, T, 6180 TInfo, ac, (Expr *)BitfieldWidth); 6181 6182 if (II) { 6183 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6184 ForRedeclaration); 6185 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6186 && !isa<TagDecl>(PrevDecl)) { 6187 Diag(Loc, diag::err_duplicate_member) << II; 6188 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6189 NewID->setInvalidDecl(); 6190 } 6191 } 6192 6193 // Process attributes attached to the ivar. 6194 ProcessDeclAttributes(S, NewID, D); 6195 6196 if (D.isInvalidType()) 6197 NewID->setInvalidDecl(); 6198 6199 if (II) { 6200 // FIXME: When interfaces are DeclContexts, we'll need to add 6201 // these to the interface. 6202 S->AddDecl(DeclPtrTy::make(NewID)); 6203 IdResolver.AddDecl(NewID); 6204 } 6205 6206 return DeclPtrTy::make(NewID); 6207} 6208 6209void Sema::ActOnFields(Scope* S, 6210 SourceLocation RecLoc, DeclPtrTy RecDecl, 6211 DeclPtrTy *Fields, unsigned NumFields, 6212 SourceLocation LBrac, SourceLocation RBrac, 6213 AttributeList *Attr) { 6214 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6215 assert(EnclosingDecl && "missing record or interface decl"); 6216 6217 // If the decl this is being inserted into is invalid, then it may be a 6218 // redeclaration or some other bogus case. Don't try to add fields to it. 6219 if (EnclosingDecl->isInvalidDecl()) { 6220 // FIXME: Deallocate fields? 6221 return; 6222 } 6223 6224 6225 // Verify that all the fields are okay. 6226 unsigned NumNamedMembers = 0; 6227 llvm::SmallVector<FieldDecl*, 32> RecFields; 6228 6229 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6230 for (unsigned i = 0; i != NumFields; ++i) { 6231 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6232 6233 // Get the type for the field. 6234 Type *FDTy = FD->getType().getTypePtr(); 6235 6236 if (!FD->isAnonymousStructOrUnion()) { 6237 // Remember all fields written by the user. 6238 RecFields.push_back(FD); 6239 } 6240 6241 // If the field is already invalid for some reason, don't emit more 6242 // diagnostics about it. 6243 if (FD->isInvalidDecl()) { 6244 EnclosingDecl->setInvalidDecl(); 6245 continue; 6246 } 6247 6248 // C99 6.7.2.1p2: 6249 // A structure or union shall not contain a member with 6250 // incomplete or function type (hence, a structure shall not 6251 // contain an instance of itself, but may contain a pointer to 6252 // an instance of itself), except that the last member of a 6253 // structure with more than one named member may have incomplete 6254 // array type; such a structure (and any union containing, 6255 // possibly recursively, a member that is such a structure) 6256 // shall not be a member of a structure or an element of an 6257 // array. 6258 if (FDTy->isFunctionType()) { 6259 // Field declared as a function. 6260 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6261 << FD->getDeclName(); 6262 FD->setInvalidDecl(); 6263 EnclosingDecl->setInvalidDecl(); 6264 continue; 6265 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6266 Record && Record->isStruct()) { 6267 // Flexible array member. 6268 if (NumNamedMembers < 1) { 6269 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6270 << FD->getDeclName(); 6271 FD->setInvalidDecl(); 6272 EnclosingDecl->setInvalidDecl(); 6273 continue; 6274 } 6275 if (!FD->getType()->isDependentType() && 6276 !Context.getBaseElementType(FD->getType())->isPODType()) { 6277 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6278 << FD->getDeclName() << FD->getType(); 6279 FD->setInvalidDecl(); 6280 EnclosingDecl->setInvalidDecl(); 6281 continue; 6282 } 6283 6284 // Okay, we have a legal flexible array member at the end of the struct. 6285 if (Record) 6286 Record->setHasFlexibleArrayMember(true); 6287 } else if (!FDTy->isDependentType() && 6288 RequireCompleteType(FD->getLocation(), FD->getType(), 6289 diag::err_field_incomplete)) { 6290 // Incomplete type 6291 FD->setInvalidDecl(); 6292 EnclosingDecl->setInvalidDecl(); 6293 continue; 6294 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6295 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6296 // If this is a member of a union, then entire union becomes "flexible". 6297 if (Record && Record->isUnion()) { 6298 Record->setHasFlexibleArrayMember(true); 6299 } else { 6300 // If this is a struct/class and this is not the last element, reject 6301 // it. Note that GCC supports variable sized arrays in the middle of 6302 // structures. 6303 if (i != NumFields-1) 6304 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6305 << FD->getDeclName() << FD->getType(); 6306 else { 6307 // We support flexible arrays at the end of structs in 6308 // other structs as an extension. 6309 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6310 << FD->getDeclName(); 6311 if (Record) 6312 Record->setHasFlexibleArrayMember(true); 6313 } 6314 } 6315 } 6316 if (Record && FDTTy->getDecl()->hasObjectMember()) 6317 Record->setHasObjectMember(true); 6318 } else if (FDTy->isObjCObjectType()) { 6319 /// A field cannot be an Objective-c object 6320 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6321 FD->setInvalidDecl(); 6322 EnclosingDecl->setInvalidDecl(); 6323 continue; 6324 } else if (getLangOptions().ObjC1 && 6325 getLangOptions().getGCMode() != LangOptions::NonGC && 6326 Record && 6327 (FD->getType()->isObjCObjectPointerType() || 6328 FD->getType().isObjCGCStrong())) 6329 Record->setHasObjectMember(true); 6330 else if (Context.getAsArrayType(FD->getType())) { 6331 QualType BaseType = Context.getBaseElementType(FD->getType()); 6332 if (Record && BaseType->isRecordType() && 6333 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6334 Record->setHasObjectMember(true); 6335 } 6336 // Keep track of the number of named members. 6337 if (FD->getIdentifier()) 6338 ++NumNamedMembers; 6339 } 6340 6341 // Okay, we successfully defined 'Record'. 6342 if (Record) { 6343 Record->completeDefinition(); 6344 } else { 6345 ObjCIvarDecl **ClsFields = 6346 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6347 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6348 ID->setLocEnd(RBrac); 6349 // Add ivar's to class's DeclContext. 6350 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6351 ClsFields[i]->setLexicalDeclContext(ID); 6352 ID->addDecl(ClsFields[i]); 6353 } 6354 // Must enforce the rule that ivars in the base classes may not be 6355 // duplicates. 6356 if (ID->getSuperClass()) 6357 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6358 } else if (ObjCImplementationDecl *IMPDecl = 6359 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6360 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6361 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6362 // Ivar declared in @implementation never belongs to the implementation. 6363 // Only it is in implementation's lexical context. 6364 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6365 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6366 } else if (ObjCCategoryDecl *CDecl = 6367 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6368 // case of ivars in class extension; all other cases have been 6369 // reported as errors elsewhere. 6370 // FIXME. Class extension does not have a LocEnd field. 6371 // CDecl->setLocEnd(RBrac); 6372 // Add ivar's to class extension's DeclContext. 6373 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6374 ClsFields[i]->setLexicalDeclContext(CDecl); 6375 CDecl->addDecl(ClsFields[i]); 6376 } 6377 } 6378 } 6379 6380 if (Attr) 6381 ProcessDeclAttributeList(S, Record, Attr); 6382 6383 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6384 // set the visibility of this record. 6385 if (Record && !Record->getDeclContext()->isRecord()) 6386 AddPushedVisibilityAttribute(Record); 6387} 6388 6389/// \brief Determine whether the given integral value is representable within 6390/// the given type T. 6391static bool isRepresentableIntegerValue(ASTContext &Context, 6392 llvm::APSInt &Value, 6393 QualType T) { 6394 assert(T->isIntegralType(Context) && "Integral type required!"); 6395 unsigned BitWidth = Context.getIntWidth(T); 6396 6397 if (Value.isUnsigned() || Value.isNonNegative()) 6398 return Value.getActiveBits() < BitWidth; 6399 6400 return Value.getMinSignedBits() <= BitWidth; 6401} 6402 6403// \brief Given an integral type, return the next larger integral type 6404// (or a NULL type of no such type exists). 6405static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6406 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6407 // enum checking below. 6408 assert(T->isIntegralType(Context) && "Integral type required!"); 6409 const unsigned NumTypes = 4; 6410 QualType SignedIntegralTypes[NumTypes] = { 6411 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6412 }; 6413 QualType UnsignedIntegralTypes[NumTypes] = { 6414 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6415 Context.UnsignedLongLongTy 6416 }; 6417 6418 unsigned BitWidth = Context.getTypeSize(T); 6419 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6420 : UnsignedIntegralTypes; 6421 for (unsigned I = 0; I != NumTypes; ++I) 6422 if (Context.getTypeSize(Types[I]) > BitWidth) 6423 return Types[I]; 6424 6425 return QualType(); 6426} 6427 6428EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6429 EnumConstantDecl *LastEnumConst, 6430 SourceLocation IdLoc, 6431 IdentifierInfo *Id, 6432 ExprArg val) { 6433 Expr *Val = (Expr *)val.get(); 6434 6435 unsigned IntWidth = Context.Target.getIntWidth(); 6436 llvm::APSInt EnumVal(IntWidth); 6437 QualType EltTy; 6438 if (Val) { 6439 if (Enum->isDependentType() || Val->isTypeDependent()) 6440 EltTy = Context.DependentTy; 6441 else { 6442 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6443 SourceLocation ExpLoc; 6444 if (!Val->isValueDependent() && 6445 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6446 Val = 0; 6447 } else { 6448 if (!getLangOptions().CPlusPlus) { 6449 // C99 6.7.2.2p2: 6450 // The expression that defines the value of an enumeration constant 6451 // shall be an integer constant expression that has a value 6452 // representable as an int. 6453 6454 // Complain if the value is not representable in an int. 6455 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6456 Diag(IdLoc, diag::ext_enum_value_not_int) 6457 << EnumVal.toString(10) << Val->getSourceRange() 6458 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6459 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6460 // Force the type of the expression to 'int'. 6461 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6462 6463 if (Val != val.get()) { 6464 val.release(); 6465 val = Val; 6466 } 6467 } 6468 } 6469 6470 // C++0x [dcl.enum]p5: 6471 // If the underlying type is not fixed, the type of each enumerator 6472 // is the type of its initializing value: 6473 // - If an initializer is specified for an enumerator, the 6474 // initializing value has the same type as the expression. 6475 EltTy = Val->getType(); 6476 } 6477 } 6478 } 6479 6480 if (!Val) { 6481 if (Enum->isDependentType()) 6482 EltTy = Context.DependentTy; 6483 else if (!LastEnumConst) { 6484 // C++0x [dcl.enum]p5: 6485 // If the underlying type is not fixed, the type of each enumerator 6486 // is the type of its initializing value: 6487 // - If no initializer is specified for the first enumerator, the 6488 // initializing value has an unspecified integral type. 6489 // 6490 // GCC uses 'int' for its unspecified integral type, as does 6491 // C99 6.7.2.2p3. 6492 EltTy = Context.IntTy; 6493 } else { 6494 // Assign the last value + 1. 6495 EnumVal = LastEnumConst->getInitVal(); 6496 ++EnumVal; 6497 EltTy = LastEnumConst->getType(); 6498 6499 // Check for overflow on increment. 6500 if (EnumVal < LastEnumConst->getInitVal()) { 6501 // C++0x [dcl.enum]p5: 6502 // If the underlying type is not fixed, the type of each enumerator 6503 // is the type of its initializing value: 6504 // 6505 // - Otherwise the type of the initializing value is the same as 6506 // the type of the initializing value of the preceding enumerator 6507 // unless the incremented value is not representable in that type, 6508 // in which case the type is an unspecified integral type 6509 // sufficient to contain the incremented value. If no such type 6510 // exists, the program is ill-formed. 6511 QualType T = getNextLargerIntegralType(Context, EltTy); 6512 if (T.isNull()) { 6513 // There is no integral type larger enough to represent this 6514 // value. Complain, then allow the value to wrap around. 6515 EnumVal = LastEnumConst->getInitVal(); 6516 EnumVal.zext(EnumVal.getBitWidth() * 2); 6517 Diag(IdLoc, diag::warn_enumerator_too_large) 6518 << EnumVal.toString(10); 6519 } else { 6520 EltTy = T; 6521 } 6522 6523 // Retrieve the last enumerator's value, extent that type to the 6524 // type that is supposed to be large enough to represent the incremented 6525 // value, then increment. 6526 EnumVal = LastEnumConst->getInitVal(); 6527 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6528 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6529 ++EnumVal; 6530 6531 // If we're not in C++, diagnose the overflow of enumerator values, 6532 // which in C99 means that the enumerator value is not representable in 6533 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6534 // permits enumerator values that are representable in some larger 6535 // integral type. 6536 if (!getLangOptions().CPlusPlus && !T.isNull()) 6537 Diag(IdLoc, diag::warn_enum_value_overflow); 6538 } else if (!getLangOptions().CPlusPlus && 6539 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6540 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6541 Diag(IdLoc, diag::ext_enum_value_not_int) 6542 << EnumVal.toString(10) << 1; 6543 } 6544 } 6545 } 6546 6547 if (!EltTy->isDependentType()) { 6548 // Make the enumerator value match the signedness and size of the 6549 // enumerator's type. 6550 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6551 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6552 } 6553 6554 val.release(); 6555 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6556 Val, EnumVal); 6557} 6558 6559 6560Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6561 DeclPtrTy lastEnumConst, 6562 SourceLocation IdLoc, 6563 IdentifierInfo *Id, 6564 SourceLocation EqualLoc, ExprTy *val) { 6565 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6566 EnumConstantDecl *LastEnumConst = 6567 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6568 Expr *Val = static_cast<Expr*>(val); 6569 6570 // The scope passed in may not be a decl scope. Zip up the scope tree until 6571 // we find one that is. 6572 S = getNonFieldDeclScope(S); 6573 6574 // Verify that there isn't already something declared with this name in this 6575 // scope. 6576 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6577 ForRedeclaration); 6578 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6579 // Maybe we will complain about the shadowed template parameter. 6580 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6581 // Just pretend that we didn't see the previous declaration. 6582 PrevDecl = 0; 6583 } 6584 6585 if (PrevDecl) { 6586 // When in C++, we may get a TagDecl with the same name; in this case the 6587 // enum constant will 'hide' the tag. 6588 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6589 "Received TagDecl when not in C++!"); 6590 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6591 if (isa<EnumConstantDecl>(PrevDecl)) 6592 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6593 else 6594 Diag(IdLoc, diag::err_redefinition) << Id; 6595 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6596 return DeclPtrTy(); 6597 } 6598 } 6599 6600 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6601 IdLoc, Id, Owned(Val)); 6602 6603 // Register this decl in the current scope stack. 6604 if (New) { 6605 New->setAccess(TheEnumDecl->getAccess()); 6606 PushOnScopeChains(New, S); 6607 } 6608 6609 return DeclPtrTy::make(New); 6610} 6611 6612void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6613 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6614 DeclPtrTy *Elements, unsigned NumElements, 6615 Scope *S, AttributeList *Attr) { 6616 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6617 QualType EnumType = Context.getTypeDeclType(Enum); 6618 6619 if (Attr) 6620 ProcessDeclAttributeList(S, Enum, Attr); 6621 6622 if (Enum->isDependentType()) { 6623 for (unsigned i = 0; i != NumElements; ++i) { 6624 EnumConstantDecl *ECD = 6625 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6626 if (!ECD) continue; 6627 6628 ECD->setType(EnumType); 6629 } 6630 6631 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6632 return; 6633 } 6634 6635 // TODO: If the result value doesn't fit in an int, it must be a long or long 6636 // long value. ISO C does not support this, but GCC does as an extension, 6637 // emit a warning. 6638 unsigned IntWidth = Context.Target.getIntWidth(); 6639 unsigned CharWidth = Context.Target.getCharWidth(); 6640 unsigned ShortWidth = Context.Target.getShortWidth(); 6641 6642 // Verify that all the values are okay, compute the size of the values, and 6643 // reverse the list. 6644 unsigned NumNegativeBits = 0; 6645 unsigned NumPositiveBits = 0; 6646 6647 // Keep track of whether all elements have type int. 6648 bool AllElementsInt = true; 6649 6650 for (unsigned i = 0; i != NumElements; ++i) { 6651 EnumConstantDecl *ECD = 6652 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6653 if (!ECD) continue; // Already issued a diagnostic. 6654 6655 const llvm::APSInt &InitVal = ECD->getInitVal(); 6656 6657 // Keep track of the size of positive and negative values. 6658 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6659 NumPositiveBits = std::max(NumPositiveBits, 6660 (unsigned)InitVal.getActiveBits()); 6661 else 6662 NumNegativeBits = std::max(NumNegativeBits, 6663 (unsigned)InitVal.getMinSignedBits()); 6664 6665 // Keep track of whether every enum element has type int (very commmon). 6666 if (AllElementsInt) 6667 AllElementsInt = ECD->getType() == Context.IntTy; 6668 } 6669 6670 // Figure out the type that should be used for this enum. 6671 // FIXME: Support -fshort-enums. 6672 QualType BestType; 6673 unsigned BestWidth; 6674 6675 // C++0x N3000 [conv.prom]p3: 6676 // An rvalue of an unscoped enumeration type whose underlying 6677 // type is not fixed can be converted to an rvalue of the first 6678 // of the following types that can represent all the values of 6679 // the enumeration: int, unsigned int, long int, unsigned long 6680 // int, long long int, or unsigned long long int. 6681 // C99 6.4.4.3p2: 6682 // An identifier declared as an enumeration constant has type int. 6683 // The C99 rule is modified by a gcc extension 6684 QualType BestPromotionType; 6685 6686 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6687 6688 if (NumNegativeBits) { 6689 // If there is a negative value, figure out the smallest integer type (of 6690 // int/long/longlong) that fits. 6691 // If it's packed, check also if it fits a char or a short. 6692 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6693 BestType = Context.SignedCharTy; 6694 BestWidth = CharWidth; 6695 } else if (Packed && NumNegativeBits <= ShortWidth && 6696 NumPositiveBits < ShortWidth) { 6697 BestType = Context.ShortTy; 6698 BestWidth = ShortWidth; 6699 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6700 BestType = Context.IntTy; 6701 BestWidth = IntWidth; 6702 } else { 6703 BestWidth = Context.Target.getLongWidth(); 6704 6705 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6706 BestType = Context.LongTy; 6707 } else { 6708 BestWidth = Context.Target.getLongLongWidth(); 6709 6710 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6711 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6712 BestType = Context.LongLongTy; 6713 } 6714 } 6715 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6716 } else { 6717 // If there is no negative value, figure out the smallest type that fits 6718 // all of the enumerator values. 6719 // If it's packed, check also if it fits a char or a short. 6720 if (Packed && NumPositiveBits <= CharWidth) { 6721 BestType = Context.UnsignedCharTy; 6722 BestPromotionType = Context.IntTy; 6723 BestWidth = CharWidth; 6724 } else if (Packed && NumPositiveBits <= ShortWidth) { 6725 BestType = Context.UnsignedShortTy; 6726 BestPromotionType = Context.IntTy; 6727 BestWidth = ShortWidth; 6728 } else if (NumPositiveBits <= IntWidth) { 6729 BestType = Context.UnsignedIntTy; 6730 BestWidth = IntWidth; 6731 BestPromotionType 6732 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6733 ? Context.UnsignedIntTy : Context.IntTy; 6734 } else if (NumPositiveBits <= 6735 (BestWidth = Context.Target.getLongWidth())) { 6736 BestType = Context.UnsignedLongTy; 6737 BestPromotionType 6738 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6739 ? Context.UnsignedLongTy : Context.LongTy; 6740 } else { 6741 BestWidth = Context.Target.getLongLongWidth(); 6742 assert(NumPositiveBits <= BestWidth && 6743 "How could an initializer get larger than ULL?"); 6744 BestType = Context.UnsignedLongLongTy; 6745 BestPromotionType 6746 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6747 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6748 } 6749 } 6750 6751 // Loop over all of the enumerator constants, changing their types to match 6752 // the type of the enum if needed. 6753 for (unsigned i = 0; i != NumElements; ++i) { 6754 EnumConstantDecl *ECD = 6755 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6756 if (!ECD) continue; // Already issued a diagnostic. 6757 6758 // Standard C says the enumerators have int type, but we allow, as an 6759 // extension, the enumerators to be larger than int size. If each 6760 // enumerator value fits in an int, type it as an int, otherwise type it the 6761 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6762 // that X has type 'int', not 'unsigned'. 6763 6764 // Determine whether the value fits into an int. 6765 llvm::APSInt InitVal = ECD->getInitVal(); 6766 6767 // If it fits into an integer type, force it. Otherwise force it to match 6768 // the enum decl type. 6769 QualType NewTy; 6770 unsigned NewWidth; 6771 bool NewSign; 6772 if (!getLangOptions().CPlusPlus && 6773 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6774 NewTy = Context.IntTy; 6775 NewWidth = IntWidth; 6776 NewSign = true; 6777 } else if (ECD->getType() == BestType) { 6778 // Already the right type! 6779 if (getLangOptions().CPlusPlus) 6780 // C++ [dcl.enum]p4: Following the closing brace of an 6781 // enum-specifier, each enumerator has the type of its 6782 // enumeration. 6783 ECD->setType(EnumType); 6784 continue; 6785 } else { 6786 NewTy = BestType; 6787 NewWidth = BestWidth; 6788 NewSign = BestType->isSignedIntegerType(); 6789 } 6790 6791 // Adjust the APSInt value. 6792 InitVal.extOrTrunc(NewWidth); 6793 InitVal.setIsSigned(NewSign); 6794 ECD->setInitVal(InitVal); 6795 6796 // Adjust the Expr initializer and type. 6797 if (ECD->getInitExpr()) 6798 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6799 CastExpr::CK_IntegralCast, 6800 ECD->getInitExpr(), 6801 CXXBaseSpecifierArray(), 6802 ImplicitCastExpr::RValue)); 6803 if (getLangOptions().CPlusPlus) 6804 // C++ [dcl.enum]p4: Following the closing brace of an 6805 // enum-specifier, each enumerator has the type of its 6806 // enumeration. 6807 ECD->setType(EnumType); 6808 else 6809 ECD->setType(NewTy); 6810 } 6811 6812 Enum->completeDefinition(BestType, BestPromotionType, 6813 NumPositiveBits, NumNegativeBits); 6814} 6815 6816Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6817 ExprArg expr) { 6818 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6819 6820 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6821 Loc, AsmString); 6822 CurContext->addDecl(New); 6823 return DeclPtrTy::make(New); 6824} 6825 6826void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6827 SourceLocation PragmaLoc, 6828 SourceLocation NameLoc) { 6829 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6830 6831 if (PrevDecl) { 6832 PrevDecl->addAttr(::new (Context) WeakAttr()); 6833 } else { 6834 (void)WeakUndeclaredIdentifiers.insert( 6835 std::pair<IdentifierInfo*,WeakInfo> 6836 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6837 } 6838} 6839 6840void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6841 IdentifierInfo* AliasName, 6842 SourceLocation PragmaLoc, 6843 SourceLocation NameLoc, 6844 SourceLocation AliasNameLoc) { 6845 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6846 LookupOrdinaryName); 6847 WeakInfo W = WeakInfo(Name, NameLoc); 6848 6849 if (PrevDecl) { 6850 if (!PrevDecl->hasAttr<AliasAttr>()) 6851 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6852 DeclApplyPragmaWeak(TUScope, ND, W); 6853 } else { 6854 (void)WeakUndeclaredIdentifiers.insert( 6855 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6856 } 6857} 6858