SemaDecl.cpp revision 11148974368f811dd0822885300f3fb39192c2f5
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isNotEmpty()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, so build a 91 // DependentNameType node to describe the type. 92 return CheckTypenameType(ETK_None, 93 (NestedNameSpecifier *)SS->getScopeRep(), 94 II, SS->getRange()).getAsOpaquePtr(); 95 } 96 97 return 0; 98 } 99 100 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 101 return 0; 102 } 103 104 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 105 // lookup for class-names. 106 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 107 LookupOrdinaryName; 108 LookupResult Result(*this, &II, NameLoc, Kind); 109 if (LookupCtx) { 110 // Perform "qualified" name lookup into the declaration context we 111 // computed, which is either the type of the base of a member access 112 // expression or the declaration context associated with a prior 113 // nested-name-specifier. 114 LookupQualifiedName(Result, LookupCtx); 115 116 if (ObjectTypePtr && Result.empty()) { 117 // C++ [basic.lookup.classref]p3: 118 // If the unqualified-id is ~type-name, the type-name is looked up 119 // in the context of the entire postfix-expression. If the type T of 120 // the object expression is of a class type C, the type-name is also 121 // looked up in the scope of class C. At least one of the lookups shall 122 // find a name that refers to (possibly cv-qualified) T. 123 LookupName(Result, S); 124 } 125 } else { 126 // Perform unqualified name lookup. 127 LookupName(Result, S); 128 } 129 130 NamedDecl *IIDecl = 0; 131 switch (Result.getResultKind()) { 132 case LookupResult::NotFound: 133 case LookupResult::NotFoundInCurrentInstantiation: 134 case LookupResult::FoundOverloaded: 135 case LookupResult::FoundUnresolvedValue: 136 Result.suppressDiagnostics(); 137 return 0; 138 139 case LookupResult::Ambiguous: 140 // Recover from type-hiding ambiguities by hiding the type. We'll 141 // do the lookup again when looking for an object, and we can 142 // diagnose the error then. If we don't do this, then the error 143 // about hiding the type will be immediately followed by an error 144 // that only makes sense if the identifier was treated like a type. 145 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 146 Result.suppressDiagnostics(); 147 return 0; 148 } 149 150 // Look to see if we have a type anywhere in the list of results. 151 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 152 Res != ResEnd; ++Res) { 153 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 154 if (!IIDecl || 155 (*Res)->getLocation().getRawEncoding() < 156 IIDecl->getLocation().getRawEncoding()) 157 IIDecl = *Res; 158 } 159 } 160 161 if (!IIDecl) { 162 // None of the entities we found is a type, so there is no way 163 // to even assume that the result is a type. In this case, don't 164 // complain about the ambiguity. The parser will either try to 165 // perform this lookup again (e.g., as an object name), which 166 // will produce the ambiguity, or will complain that it expected 167 // a type name. 168 Result.suppressDiagnostics(); 169 return 0; 170 } 171 172 // We found a type within the ambiguous lookup; diagnose the 173 // ambiguity and then return that type. This might be the right 174 // answer, or it might not be, but it suppresses any attempt to 175 // perform the name lookup again. 176 break; 177 178 case LookupResult::Found: 179 IIDecl = Result.getFoundDecl(); 180 break; 181 } 182 183 assert(IIDecl && "Didn't find decl"); 184 185 QualType T; 186 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 187 DiagnoseUseOfDecl(IIDecl, NameLoc); 188 189 if (T.isNull()) 190 T = Context.getTypeDeclType(TD); 191 192 if (SS) 193 T = getQualifiedNameType(*SS, T); 194 195 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 196 T = Context.getObjCInterfaceType(IDecl); 197 } else if (UnresolvedUsingTypenameDecl *UUDecl = 198 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 199 // FIXME: preserve source structure information. 200 T = Context.getDependentNameType(ETK_None, 201 UUDecl->getTargetNestedNameSpecifier(), 202 &II); 203 } else { 204 // If it's not plausibly a type, suppress diagnostics. 205 Result.suppressDiagnostics(); 206 return 0; 207 } 208 209 return T.getAsOpaquePtr(); 210} 211 212/// isTagName() - This method is called *for error recovery purposes only* 213/// to determine if the specified name is a valid tag name ("struct foo"). If 214/// so, this returns the TST for the tag corresponding to it (TST_enum, 215/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 216/// where the user forgot to specify the tag. 217DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 218 // Do a tag name lookup in this scope. 219 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 220 LookupName(R, S, false); 221 R.suppressDiagnostics(); 222 if (R.getResultKind() == LookupResult::Found) 223 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 224 switch (TD->getTagKind()) { 225 case TagDecl::TK_struct: return DeclSpec::TST_struct; 226 case TagDecl::TK_union: return DeclSpec::TST_union; 227 case TagDecl::TK_class: return DeclSpec::TST_class; 228 case TagDecl::TK_enum: return DeclSpec::TST_enum; 229 } 230 } 231 232 return DeclSpec::TST_unspecified; 233} 234 235bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 236 SourceLocation IILoc, 237 Scope *S, 238 CXXScopeSpec *SS, 239 TypeTy *&SuggestedType) { 240 // We don't have anything to suggest (yet). 241 SuggestedType = 0; 242 243 // There may have been a typo in the name of the type. Look up typo 244 // results, in case we have something that we can suggest. 245 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 246 NotForRedeclaration); 247 248 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 249 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 250 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 251 !Result->isInvalidDecl()) { 252 // We found a similarly-named type or interface; suggest that. 253 if (!SS || !SS->isSet()) 254 Diag(IILoc, diag::err_unknown_typename_suggest) 255 << &II << Lookup.getLookupName() 256 << FixItHint::CreateReplacement(SourceRange(IILoc), 257 Result->getNameAsString()); 258 else if (DeclContext *DC = computeDeclContext(*SS, false)) 259 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 260 << &II << DC << Lookup.getLookupName() << SS->getRange() 261 << FixItHint::CreateReplacement(SourceRange(IILoc), 262 Result->getNameAsString()); 263 else 264 llvm_unreachable("could not have corrected a typo here"); 265 266 Diag(Result->getLocation(), diag::note_previous_decl) 267 << Result->getDeclName(); 268 269 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 270 return true; 271 } 272 } else if (Lookup.empty()) { 273 // We corrected to a keyword. 274 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 275 Diag(IILoc, diag::err_unknown_typename_suggest) 276 << &II << Corrected; 277 return true; 278 } 279 } 280 281 if (getLangOptions().CPlusPlus) { 282 // See if II is a class template that the user forgot to pass arguments to. 283 UnqualifiedId Name; 284 Name.setIdentifier(&II, IILoc); 285 CXXScopeSpec EmptySS; 286 TemplateTy TemplateResult; 287 if (isTemplateName(S, SS ? *SS : EmptySS, Name, 0, true, TemplateResult) 288 == TNK_Type_template) { 289 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 290 Diag(IILoc, diag::err_template_missing_args) << TplName; 291 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 292 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 293 << TplDecl->getTemplateParameters()->getSourceRange(); 294 } 295 return true; 296 } 297 } 298 299 // FIXME: Should we move the logic that tries to recover from a missing tag 300 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 301 302 if (!SS || (!SS->isSet() && !SS->isInvalid())) 303 Diag(IILoc, diag::err_unknown_typename) << &II; 304 else if (DeclContext *DC = computeDeclContext(*SS, false)) 305 Diag(IILoc, diag::err_typename_nested_not_found) 306 << &II << DC << SS->getRange(); 307 else if (isDependentScopeSpecifier(*SS)) { 308 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 309 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 310 << SourceRange(SS->getRange().getBegin(), IILoc) 311 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 312 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 313 } else { 314 assert(SS && SS->isInvalid() && 315 "Invalid scope specifier has already been diagnosed"); 316 } 317 318 return true; 319} 320 321// Determines the context to return to after temporarily entering a 322// context. This depends in an unnecessarily complicated way on the 323// exact ordering of callbacks from the parser. 324DeclContext *Sema::getContainingDC(DeclContext *DC) { 325 326 // Functions defined inline within classes aren't parsed until we've 327 // finished parsing the top-level class, so the top-level class is 328 // the context we'll need to return to. 329 if (isa<FunctionDecl>(DC)) { 330 DC = DC->getLexicalParent(); 331 332 // A function not defined within a class will always return to its 333 // lexical context. 334 if (!isa<CXXRecordDecl>(DC)) 335 return DC; 336 337 // A C++ inline method/friend is parsed *after* the topmost class 338 // it was declared in is fully parsed ("complete"); the topmost 339 // class is the context we need to return to. 340 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 341 DC = RD; 342 343 // Return the declaration context of the topmost class the inline method is 344 // declared in. 345 return DC; 346 } 347 348 if (isa<ObjCMethodDecl>(DC)) 349 return Context.getTranslationUnitDecl(); 350 351 return DC->getLexicalParent(); 352} 353 354void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 355 assert(getContainingDC(DC) == CurContext && 356 "The next DeclContext should be lexically contained in the current one."); 357 CurContext = DC; 358 S->setEntity(DC); 359} 360 361void Sema::PopDeclContext() { 362 assert(CurContext && "DeclContext imbalance!"); 363 364 CurContext = getContainingDC(CurContext); 365} 366 367/// EnterDeclaratorContext - Used when we must lookup names in the context 368/// of a declarator's nested name specifier. 369/// 370void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 371 // C++0x [basic.lookup.unqual]p13: 372 // A name used in the definition of a static data member of class 373 // X (after the qualified-id of the static member) is looked up as 374 // if the name was used in a member function of X. 375 // C++0x [basic.lookup.unqual]p14: 376 // If a variable member of a namespace is defined outside of the 377 // scope of its namespace then any name used in the definition of 378 // the variable member (after the declarator-id) is looked up as 379 // if the definition of the variable member occurred in its 380 // namespace. 381 // Both of these imply that we should push a scope whose context 382 // is the semantic context of the declaration. We can't use 383 // PushDeclContext here because that context is not necessarily 384 // lexically contained in the current context. Fortunately, 385 // the containing scope should have the appropriate information. 386 387 assert(!S->getEntity() && "scope already has entity"); 388 389#ifndef NDEBUG 390 Scope *Ancestor = S->getParent(); 391 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 392 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 393#endif 394 395 CurContext = DC; 396 S->setEntity(DC); 397} 398 399void Sema::ExitDeclaratorContext(Scope *S) { 400 assert(S->getEntity() == CurContext && "Context imbalance!"); 401 402 // Switch back to the lexical context. The safety of this is 403 // enforced by an assert in EnterDeclaratorContext. 404 Scope *Ancestor = S->getParent(); 405 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 406 CurContext = (DeclContext*) Ancestor->getEntity(); 407 408 // We don't need to do anything with the scope, which is going to 409 // disappear. 410} 411 412/// \brief Determine whether we allow overloading of the function 413/// PrevDecl with another declaration. 414/// 415/// This routine determines whether overloading is possible, not 416/// whether some new function is actually an overload. It will return 417/// true in C++ (where we can always provide overloads) or, as an 418/// extension, in C when the previous function is already an 419/// overloaded function declaration or has the "overloadable" 420/// attribute. 421static bool AllowOverloadingOfFunction(LookupResult &Previous, 422 ASTContext &Context) { 423 if (Context.getLangOptions().CPlusPlus) 424 return true; 425 426 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 427 return true; 428 429 return (Previous.getResultKind() == LookupResult::Found 430 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 431} 432 433/// Add this decl to the scope shadowed decl chains. 434void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 435 // Move up the scope chain until we find the nearest enclosing 436 // non-transparent context. The declaration will be introduced into this 437 // scope. 438 while (S->getEntity() && 439 ((DeclContext *)S->getEntity())->isTransparentContext()) 440 S = S->getParent(); 441 442 // Add scoped declarations into their context, so that they can be 443 // found later. Declarations without a context won't be inserted 444 // into any context. 445 if (AddToContext) 446 CurContext->addDecl(D); 447 448 // Out-of-line definitions shouldn't be pushed into scope in C++. 449 // Out-of-line variable and function definitions shouldn't even in C. 450 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 451 D->isOutOfLine()) 452 return; 453 454 // Template instantiations should also not be pushed into scope. 455 if (isa<FunctionDecl>(D) && 456 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 457 return; 458 459 // If this replaces anything in the current scope, 460 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 461 IEnd = IdResolver.end(); 462 for (; I != IEnd; ++I) { 463 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 464 S->RemoveDecl(DeclPtrTy::make(*I)); 465 IdResolver.RemoveDecl(*I); 466 467 // Should only need to replace one decl. 468 break; 469 } 470 } 471 472 S->AddDecl(DeclPtrTy::make(D)); 473 IdResolver.AddDecl(D); 474} 475 476bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 477 return IdResolver.isDeclInScope(D, Ctx, Context, S); 478} 479 480static bool isOutOfScopePreviousDeclaration(NamedDecl *, 481 DeclContext*, 482 ASTContext&); 483 484/// Filters out lookup results that don't fall within the given scope 485/// as determined by isDeclInScope. 486static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 487 DeclContext *Ctx, Scope *S, 488 bool ConsiderLinkage) { 489 LookupResult::Filter F = R.makeFilter(); 490 while (F.hasNext()) { 491 NamedDecl *D = F.next(); 492 493 if (SemaRef.isDeclInScope(D, Ctx, S)) 494 continue; 495 496 if (ConsiderLinkage && 497 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 498 continue; 499 500 F.erase(); 501 } 502 503 F.done(); 504} 505 506static bool isUsingDecl(NamedDecl *D) { 507 return isa<UsingShadowDecl>(D) || 508 isa<UnresolvedUsingTypenameDecl>(D) || 509 isa<UnresolvedUsingValueDecl>(D); 510} 511 512/// Removes using shadow declarations from the lookup results. 513static void RemoveUsingDecls(LookupResult &R) { 514 LookupResult::Filter F = R.makeFilter(); 515 while (F.hasNext()) 516 if (isUsingDecl(F.next())) 517 F.erase(); 518 519 F.done(); 520} 521 522static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 523 if (D->isInvalidDecl()) 524 return false; 525 526 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 527 return false; 528 529 // White-list anything that isn't a local variable. 530 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 531 !D->getDeclContext()->isFunctionOrMethod()) 532 return false; 533 534 // Types of valid local variables should be complete, so this should succeed. 535 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 536 537 // White-list anything with an __attribute__((unused)) type. 538 QualType Ty = VD->getType(); 539 540 // Only look at the outermost level of typedef. 541 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 542 if (TT->getDecl()->hasAttr<UnusedAttr>()) 543 return false; 544 } 545 546 // If we failed to complete the type for some reason, don't 547 // diagnose the variable. 548 if (Ty->isIncompleteType()) 549 return false; 550 551 if (const TagType *TT = Ty->getAs<TagType>()) { 552 const TagDecl *Tag = TT->getDecl(); 553 if (Tag->hasAttr<UnusedAttr>()) 554 return false; 555 556 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 557 if (!RD->hasTrivialConstructor()) 558 return false; 559 if (!RD->hasTrivialDestructor()) 560 return false; 561 } 562 } 563 564 // TODO: __attribute__((unused)) templates? 565 } 566 567 return true; 568} 569 570void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 571 if (S->decl_empty()) return; 572 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 573 "Scope shouldn't contain decls!"); 574 575 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 576 I != E; ++I) { 577 Decl *TmpD = (*I).getAs<Decl>(); 578 assert(TmpD && "This decl didn't get pushed??"); 579 580 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 581 NamedDecl *D = cast<NamedDecl>(TmpD); 582 583 if (!D->getDeclName()) continue; 584 585 // Diagnose unused variables in this scope. 586 if (ShouldDiagnoseUnusedDecl(D) && 587 S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 588 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 589 590 // Remove this name from our lexical scope. 591 IdResolver.RemoveDecl(D); 592 } 593} 594 595/// \brief Look for an Objective-C class in the translation unit. 596/// 597/// \param Id The name of the Objective-C class we're looking for. If 598/// typo-correction fixes this name, the Id will be updated 599/// to the fixed name. 600/// 601/// \param IdLoc The location of the name in the translation unit. 602/// 603/// \param TypoCorrection If true, this routine will attempt typo correction 604/// if there is no class with the given name. 605/// 606/// \returns The declaration of the named Objective-C class, or NULL if the 607/// class could not be found. 608ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 609 SourceLocation IdLoc, 610 bool TypoCorrection) { 611 // The third "scope" argument is 0 since we aren't enabling lazy built-in 612 // creation from this context. 613 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 614 615 if (!IDecl && TypoCorrection) { 616 // Perform typo correction at the given location, but only if we 617 // find an Objective-C class name. 618 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 619 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 620 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 621 Diag(IdLoc, diag::err_undef_interface_suggest) 622 << Id << IDecl->getDeclName() 623 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 624 Diag(IDecl->getLocation(), diag::note_previous_decl) 625 << IDecl->getDeclName(); 626 627 Id = IDecl->getIdentifier(); 628 } 629 } 630 631 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 632} 633 634/// getNonFieldDeclScope - Retrieves the innermost scope, starting 635/// from S, where a non-field would be declared. This routine copes 636/// with the difference between C and C++ scoping rules in structs and 637/// unions. For example, the following code is well-formed in C but 638/// ill-formed in C++: 639/// @code 640/// struct S6 { 641/// enum { BAR } e; 642/// }; 643/// 644/// void test_S6() { 645/// struct S6 a; 646/// a.e = BAR; 647/// } 648/// @endcode 649/// For the declaration of BAR, this routine will return a different 650/// scope. The scope S will be the scope of the unnamed enumeration 651/// within S6. In C++, this routine will return the scope associated 652/// with S6, because the enumeration's scope is a transparent 653/// context but structures can contain non-field names. In C, this 654/// routine will return the translation unit scope, since the 655/// enumeration's scope is a transparent context and structures cannot 656/// contain non-field names. 657Scope *Sema::getNonFieldDeclScope(Scope *S) { 658 while (((S->getFlags() & Scope::DeclScope) == 0) || 659 (S->getEntity() && 660 ((DeclContext *)S->getEntity())->isTransparentContext()) || 661 (S->isClassScope() && !getLangOptions().CPlusPlus)) 662 S = S->getParent(); 663 return S; 664} 665 666void Sema::InitBuiltinVaListType() { 667 if (!Context.getBuiltinVaListType().isNull()) 668 return; 669 670 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 671 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 672 LookupOrdinaryName, ForRedeclaration); 673 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 674 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 675} 676 677/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 678/// file scope. lazily create a decl for it. ForRedeclaration is true 679/// if we're creating this built-in in anticipation of redeclaring the 680/// built-in. 681NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 682 Scope *S, bool ForRedeclaration, 683 SourceLocation Loc) { 684 Builtin::ID BID = (Builtin::ID)bid; 685 686 if (Context.BuiltinInfo.hasVAListUse(BID)) 687 InitBuiltinVaListType(); 688 689 ASTContext::GetBuiltinTypeError Error; 690 QualType R = Context.GetBuiltinType(BID, Error); 691 switch (Error) { 692 case ASTContext::GE_None: 693 // Okay 694 break; 695 696 case ASTContext::GE_Missing_stdio: 697 if (ForRedeclaration) 698 Diag(Loc, diag::err_implicit_decl_requires_stdio) 699 << Context.BuiltinInfo.GetName(BID); 700 return 0; 701 702 case ASTContext::GE_Missing_setjmp: 703 if (ForRedeclaration) 704 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 705 << Context.BuiltinInfo.GetName(BID); 706 return 0; 707 } 708 709 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 710 Diag(Loc, diag::ext_implicit_lib_function_decl) 711 << Context.BuiltinInfo.GetName(BID) 712 << R; 713 if (Context.BuiltinInfo.getHeaderName(BID) && 714 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 715 != Diagnostic::Ignored) 716 Diag(Loc, diag::note_please_include_header) 717 << Context.BuiltinInfo.getHeaderName(BID) 718 << Context.BuiltinInfo.GetName(BID); 719 } 720 721 FunctionDecl *New = FunctionDecl::Create(Context, 722 Context.getTranslationUnitDecl(), 723 Loc, II, R, /*TInfo=*/0, 724 FunctionDecl::Extern, 725 FunctionDecl::None, false, 726 /*hasPrototype=*/true); 727 New->setImplicit(); 728 729 // Create Decl objects for each parameter, adding them to the 730 // FunctionDecl. 731 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 732 llvm::SmallVector<ParmVarDecl*, 16> Params; 733 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 734 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 735 FT->getArgType(i), /*TInfo=*/0, 736 VarDecl::None, VarDecl::None, 0)); 737 New->setParams(Params.data(), Params.size()); 738 } 739 740 AddKnownFunctionAttributes(New); 741 742 // TUScope is the translation-unit scope to insert this function into. 743 // FIXME: This is hideous. We need to teach PushOnScopeChains to 744 // relate Scopes to DeclContexts, and probably eliminate CurContext 745 // entirely, but we're not there yet. 746 DeclContext *SavedContext = CurContext; 747 CurContext = Context.getTranslationUnitDecl(); 748 PushOnScopeChains(New, TUScope); 749 CurContext = SavedContext; 750 return New; 751} 752 753/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 754/// same name and scope as a previous declaration 'Old'. Figure out 755/// how to resolve this situation, merging decls or emitting 756/// diagnostics as appropriate. If there was an error, set New to be invalid. 757/// 758void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 759 // If the new decl is known invalid already, don't bother doing any 760 // merging checks. 761 if (New->isInvalidDecl()) return; 762 763 // Allow multiple definitions for ObjC built-in typedefs. 764 // FIXME: Verify the underlying types are equivalent! 765 if (getLangOptions().ObjC1) { 766 const IdentifierInfo *TypeID = New->getIdentifier(); 767 switch (TypeID->getLength()) { 768 default: break; 769 case 2: 770 if (!TypeID->isStr("id")) 771 break; 772 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 773 // Install the built-in type for 'id', ignoring the current definition. 774 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 775 return; 776 case 5: 777 if (!TypeID->isStr("Class")) 778 break; 779 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 780 // Install the built-in type for 'Class', ignoring the current definition. 781 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 782 return; 783 case 3: 784 if (!TypeID->isStr("SEL")) 785 break; 786 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 787 // Install the built-in type for 'SEL', ignoring the current definition. 788 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 789 return; 790 case 8: 791 if (!TypeID->isStr("Protocol")) 792 break; 793 Context.setObjCProtoType(New->getUnderlyingType()); 794 return; 795 } 796 // Fall through - the typedef name was not a builtin type. 797 } 798 799 // Verify the old decl was also a type. 800 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 801 if (!Old) { 802 Diag(New->getLocation(), diag::err_redefinition_different_kind) 803 << New->getDeclName(); 804 805 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 806 if (OldD->getLocation().isValid()) 807 Diag(OldD->getLocation(), diag::note_previous_definition); 808 809 return New->setInvalidDecl(); 810 } 811 812 // If the old declaration is invalid, just give up here. 813 if (Old->isInvalidDecl()) 814 return New->setInvalidDecl(); 815 816 // Determine the "old" type we'll use for checking and diagnostics. 817 QualType OldType; 818 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 819 OldType = OldTypedef->getUnderlyingType(); 820 else 821 OldType = Context.getTypeDeclType(Old); 822 823 // If the typedef types are not identical, reject them in all languages and 824 // with any extensions enabled. 825 826 if (OldType != New->getUnderlyingType() && 827 Context.getCanonicalType(OldType) != 828 Context.getCanonicalType(New->getUnderlyingType())) { 829 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 830 << New->getUnderlyingType() << OldType; 831 if (Old->getLocation().isValid()) 832 Diag(Old->getLocation(), diag::note_previous_definition); 833 return New->setInvalidDecl(); 834 } 835 836 // The types match. Link up the redeclaration chain if the old 837 // declaration was a typedef. 838 // FIXME: this is a potential source of wierdness if the type 839 // spellings don't match exactly. 840 if (isa<TypedefDecl>(Old)) 841 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 842 843 if (getLangOptions().Microsoft) 844 return; 845 846 if (getLangOptions().CPlusPlus) { 847 // C++ [dcl.typedef]p2: 848 // In a given non-class scope, a typedef specifier can be used to 849 // redefine the name of any type declared in that scope to refer 850 // to the type to which it already refers. 851 if (!isa<CXXRecordDecl>(CurContext)) 852 return; 853 854 // C++0x [dcl.typedef]p4: 855 // In a given class scope, a typedef specifier can be used to redefine 856 // any class-name declared in that scope that is not also a typedef-name 857 // to refer to the type to which it already refers. 858 // 859 // This wording came in via DR424, which was a correction to the 860 // wording in DR56, which accidentally banned code like: 861 // 862 // struct S { 863 // typedef struct A { } A; 864 // }; 865 // 866 // in the C++03 standard. We implement the C++0x semantics, which 867 // allow the above but disallow 868 // 869 // struct S { 870 // typedef int I; 871 // typedef int I; 872 // }; 873 // 874 // since that was the intent of DR56. 875 if (!isa<TypedefDecl >(Old)) 876 return; 877 878 Diag(New->getLocation(), diag::err_redefinition) 879 << New->getDeclName(); 880 Diag(Old->getLocation(), diag::note_previous_definition); 881 return New->setInvalidDecl(); 882 } 883 884 // If we have a redefinition of a typedef in C, emit a warning. This warning 885 // is normally mapped to an error, but can be controlled with 886 // -Wtypedef-redefinition. If either the original or the redefinition is 887 // in a system header, don't emit this for compatibility with GCC. 888 if (getDiagnostics().getSuppressSystemWarnings() && 889 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 890 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 891 return; 892 893 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 894 << New->getDeclName(); 895 Diag(Old->getLocation(), diag::note_previous_definition); 896 return; 897} 898 899/// DeclhasAttr - returns true if decl Declaration already has the target 900/// attribute. 901static bool 902DeclHasAttr(const Decl *decl, const Attr *target) { 903 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 904 if (attr->getKind() == target->getKind()) 905 return true; 906 907 return false; 908} 909 910/// MergeAttributes - append attributes from the Old decl to the New one. 911static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 912 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 913 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 914 Attr *NewAttr = attr->clone(C); 915 NewAttr->setInherited(true); 916 New->addAttr(NewAttr); 917 } 918 } 919} 920 921/// Used in MergeFunctionDecl to keep track of function parameters in 922/// C. 923struct GNUCompatibleParamWarning { 924 ParmVarDecl *OldParm; 925 ParmVarDecl *NewParm; 926 QualType PromotedType; 927}; 928 929 930/// getSpecialMember - get the special member enum for a method. 931Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 932 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 933 if (Ctor->isCopyConstructor()) 934 return Sema::CXXCopyConstructor; 935 936 return Sema::CXXConstructor; 937 } 938 939 if (isa<CXXDestructorDecl>(MD)) 940 return Sema::CXXDestructor; 941 942 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 943 return Sema::CXXCopyAssignment; 944} 945 946/// canREdefineFunction - checks if a function can be redefined. Currently, 947/// only extern inline functions can be redefined, and even then only in 948/// GNU89 mode. 949static bool canRedefineFunction(const FunctionDecl *FD, 950 const LangOptions& LangOpts) { 951 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 952 FD->isInlineSpecified() && 953 FD->getStorageClass() == FunctionDecl::Extern); 954} 955 956/// MergeFunctionDecl - We just parsed a function 'New' from 957/// declarator D which has the same name and scope as a previous 958/// declaration 'Old'. Figure out how to resolve this situation, 959/// merging decls or emitting diagnostics as appropriate. 960/// 961/// In C++, New and Old must be declarations that are not 962/// overloaded. Use IsOverload to determine whether New and Old are 963/// overloaded, and to select the Old declaration that New should be 964/// merged with. 965/// 966/// Returns true if there was an error, false otherwise. 967bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 968 // Verify the old decl was also a function. 969 FunctionDecl *Old = 0; 970 if (FunctionTemplateDecl *OldFunctionTemplate 971 = dyn_cast<FunctionTemplateDecl>(OldD)) 972 Old = OldFunctionTemplate->getTemplatedDecl(); 973 else 974 Old = dyn_cast<FunctionDecl>(OldD); 975 if (!Old) { 976 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 977 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 978 Diag(Shadow->getTargetDecl()->getLocation(), 979 diag::note_using_decl_target); 980 Diag(Shadow->getUsingDecl()->getLocation(), 981 diag::note_using_decl) << 0; 982 return true; 983 } 984 985 Diag(New->getLocation(), diag::err_redefinition_different_kind) 986 << New->getDeclName(); 987 Diag(OldD->getLocation(), diag::note_previous_definition); 988 return true; 989 } 990 991 // Determine whether the previous declaration was a definition, 992 // implicit declaration, or a declaration. 993 diag::kind PrevDiag; 994 if (Old->isThisDeclarationADefinition()) 995 PrevDiag = diag::note_previous_definition; 996 else if (Old->isImplicit()) 997 PrevDiag = diag::note_previous_implicit_declaration; 998 else 999 PrevDiag = diag::note_previous_declaration; 1000 1001 QualType OldQType = Context.getCanonicalType(Old->getType()); 1002 QualType NewQType = Context.getCanonicalType(New->getType()); 1003 1004 // Don't complain about this if we're in GNU89 mode and the old function 1005 // is an extern inline function. 1006 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1007 New->getStorageClass() == FunctionDecl::Static && 1008 Old->getStorageClass() != FunctionDecl::Static && 1009 !canRedefineFunction(Old, getLangOptions())) { 1010 Diag(New->getLocation(), diag::err_static_non_static) 1011 << New; 1012 Diag(Old->getLocation(), PrevDiag); 1013 return true; 1014 } 1015 1016 // If a function is first declared with a calling convention, but is 1017 // later declared or defined without one, the second decl assumes the 1018 // calling convention of the first. 1019 // 1020 // For the new decl, we have to look at the NON-canonical type to tell the 1021 // difference between a function that really doesn't have a calling 1022 // convention and one that is declared cdecl. That's because in 1023 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1024 // because it is the default calling convention. 1025 // 1026 // Note also that we DO NOT return at this point, because we still have 1027 // other tests to run. 1028 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1029 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1030 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1031 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1032 if (OldTypeInfo.getCC() != CC_Default && 1033 NewTypeInfo.getCC() == CC_Default) { 1034 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1035 New->setType(NewQType); 1036 NewQType = Context.getCanonicalType(NewQType); 1037 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1038 NewTypeInfo.getCC())) { 1039 // Calling conventions really aren't compatible, so complain. 1040 Diag(New->getLocation(), diag::err_cconv_change) 1041 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1042 << (OldTypeInfo.getCC() == CC_Default) 1043 << (OldTypeInfo.getCC() == CC_Default ? "" : 1044 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1045 Diag(Old->getLocation(), diag::note_previous_declaration); 1046 return true; 1047 } 1048 1049 // FIXME: diagnose the other way around? 1050 if (OldType->getNoReturnAttr() && 1051 !NewType->getNoReturnAttr()) { 1052 NewQType = Context.getNoReturnType(NewQType); 1053 New->setType(NewQType); 1054 assert(NewQType.isCanonical()); 1055 } 1056 1057 if (getLangOptions().CPlusPlus) { 1058 // (C++98 13.1p2): 1059 // Certain function declarations cannot be overloaded: 1060 // -- Function declarations that differ only in the return type 1061 // cannot be overloaded. 1062 QualType OldReturnType 1063 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1064 QualType NewReturnType 1065 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1066 if (OldReturnType != NewReturnType) { 1067 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1068 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1069 return true; 1070 } 1071 1072 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1073 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1074 if (OldMethod && NewMethod) { 1075 // Preserve triviality. 1076 NewMethod->setTrivial(OldMethod->isTrivial()); 1077 1078 bool isFriend = NewMethod->getFriendObjectKind(); 1079 1080 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1081 // -- Member function declarations with the same name and the 1082 // same parameter types cannot be overloaded if any of them 1083 // is a static member function declaration. 1084 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1085 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1086 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1087 return true; 1088 } 1089 1090 // C++ [class.mem]p1: 1091 // [...] A member shall not be declared twice in the 1092 // member-specification, except that a nested class or member 1093 // class template can be declared and then later defined. 1094 unsigned NewDiag; 1095 if (isa<CXXConstructorDecl>(OldMethod)) 1096 NewDiag = diag::err_constructor_redeclared; 1097 else if (isa<CXXDestructorDecl>(NewMethod)) 1098 NewDiag = diag::err_destructor_redeclared; 1099 else if (isa<CXXConversionDecl>(NewMethod)) 1100 NewDiag = diag::err_conv_function_redeclared; 1101 else 1102 NewDiag = diag::err_member_redeclared; 1103 1104 Diag(New->getLocation(), NewDiag); 1105 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1106 1107 // Complain if this is an explicit declaration of a special 1108 // member that was initially declared implicitly. 1109 // 1110 // As an exception, it's okay to befriend such methods in order 1111 // to permit the implicit constructor/destructor/operator calls. 1112 } else if (OldMethod->isImplicit()) { 1113 if (isFriend) { 1114 NewMethod->setImplicit(); 1115 } else { 1116 Diag(NewMethod->getLocation(), 1117 diag::err_definition_of_implicitly_declared_member) 1118 << New << getSpecialMember(OldMethod); 1119 return true; 1120 } 1121 } 1122 } 1123 1124 // (C++98 8.3.5p3): 1125 // All declarations for a function shall agree exactly in both the 1126 // return type and the parameter-type-list. 1127 // attributes should be ignored when comparing. 1128 if (Context.getNoReturnType(OldQType, false) == 1129 Context.getNoReturnType(NewQType, false)) 1130 return MergeCompatibleFunctionDecls(New, Old); 1131 1132 // Fall through for conflicting redeclarations and redefinitions. 1133 } 1134 1135 // C: Function types need to be compatible, not identical. This handles 1136 // duplicate function decls like "void f(int); void f(enum X);" properly. 1137 if (!getLangOptions().CPlusPlus && 1138 Context.typesAreCompatible(OldQType, NewQType)) { 1139 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1140 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1141 const FunctionProtoType *OldProto = 0; 1142 if (isa<FunctionNoProtoType>(NewFuncType) && 1143 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1144 // The old declaration provided a function prototype, but the 1145 // new declaration does not. Merge in the prototype. 1146 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1147 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1148 OldProto->arg_type_end()); 1149 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1150 ParamTypes.data(), ParamTypes.size(), 1151 OldProto->isVariadic(), 1152 OldProto->getTypeQuals(), 1153 false, false, 0, 0, 1154 OldProto->getExtInfo()); 1155 New->setType(NewQType); 1156 New->setHasInheritedPrototype(); 1157 1158 // Synthesize a parameter for each argument type. 1159 llvm::SmallVector<ParmVarDecl*, 16> Params; 1160 for (FunctionProtoType::arg_type_iterator 1161 ParamType = OldProto->arg_type_begin(), 1162 ParamEnd = OldProto->arg_type_end(); 1163 ParamType != ParamEnd; ++ParamType) { 1164 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1165 SourceLocation(), 0, 1166 *ParamType, /*TInfo=*/0, 1167 VarDecl::None, VarDecl::None, 1168 0); 1169 Param->setImplicit(); 1170 Params.push_back(Param); 1171 } 1172 1173 New->setParams(Params.data(), Params.size()); 1174 } 1175 1176 return MergeCompatibleFunctionDecls(New, Old); 1177 } 1178 1179 // GNU C permits a K&R definition to follow a prototype declaration 1180 // if the declared types of the parameters in the K&R definition 1181 // match the types in the prototype declaration, even when the 1182 // promoted types of the parameters from the K&R definition differ 1183 // from the types in the prototype. GCC then keeps the types from 1184 // the prototype. 1185 // 1186 // If a variadic prototype is followed by a non-variadic K&R definition, 1187 // the K&R definition becomes variadic. This is sort of an edge case, but 1188 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1189 // C99 6.9.1p8. 1190 if (!getLangOptions().CPlusPlus && 1191 Old->hasPrototype() && !New->hasPrototype() && 1192 New->getType()->getAs<FunctionProtoType>() && 1193 Old->getNumParams() == New->getNumParams()) { 1194 llvm::SmallVector<QualType, 16> ArgTypes; 1195 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1196 const FunctionProtoType *OldProto 1197 = Old->getType()->getAs<FunctionProtoType>(); 1198 const FunctionProtoType *NewProto 1199 = New->getType()->getAs<FunctionProtoType>(); 1200 1201 // Determine whether this is the GNU C extension. 1202 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1203 NewProto->getResultType()); 1204 bool LooseCompatible = !MergedReturn.isNull(); 1205 for (unsigned Idx = 0, End = Old->getNumParams(); 1206 LooseCompatible && Idx != End; ++Idx) { 1207 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1208 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1209 if (Context.typesAreCompatible(OldParm->getType(), 1210 NewProto->getArgType(Idx))) { 1211 ArgTypes.push_back(NewParm->getType()); 1212 } else if (Context.typesAreCompatible(OldParm->getType(), 1213 NewParm->getType())) { 1214 GNUCompatibleParamWarning Warn 1215 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1216 Warnings.push_back(Warn); 1217 ArgTypes.push_back(NewParm->getType()); 1218 } else 1219 LooseCompatible = false; 1220 } 1221 1222 if (LooseCompatible) { 1223 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1224 Diag(Warnings[Warn].NewParm->getLocation(), 1225 diag::ext_param_promoted_not_compatible_with_prototype) 1226 << Warnings[Warn].PromotedType 1227 << Warnings[Warn].OldParm->getType(); 1228 Diag(Warnings[Warn].OldParm->getLocation(), 1229 diag::note_previous_declaration); 1230 } 1231 1232 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1233 ArgTypes.size(), 1234 OldProto->isVariadic(), 0, 1235 false, false, 0, 0, 1236 OldProto->getExtInfo())); 1237 return MergeCompatibleFunctionDecls(New, Old); 1238 } 1239 1240 // Fall through to diagnose conflicting types. 1241 } 1242 1243 // A function that has already been declared has been redeclared or defined 1244 // with a different type- show appropriate diagnostic 1245 if (unsigned BuiltinID = Old->getBuiltinID()) { 1246 // The user has declared a builtin function with an incompatible 1247 // signature. 1248 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1249 // The function the user is redeclaring is a library-defined 1250 // function like 'malloc' or 'printf'. Warn about the 1251 // redeclaration, then pretend that we don't know about this 1252 // library built-in. 1253 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1254 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1255 << Old << Old->getType(); 1256 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1257 Old->setInvalidDecl(); 1258 return false; 1259 } 1260 1261 PrevDiag = diag::note_previous_builtin_declaration; 1262 } 1263 1264 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1265 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1266 return true; 1267} 1268 1269/// \brief Completes the merge of two function declarations that are 1270/// known to be compatible. 1271/// 1272/// This routine handles the merging of attributes and other 1273/// properties of function declarations form the old declaration to 1274/// the new declaration, once we know that New is in fact a 1275/// redeclaration of Old. 1276/// 1277/// \returns false 1278bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1279 // Merge the attributes 1280 MergeAttributes(New, Old, Context); 1281 1282 // Merge the storage class. 1283 if (Old->getStorageClass() != FunctionDecl::Extern && 1284 Old->getStorageClass() != FunctionDecl::None) 1285 New->setStorageClass(Old->getStorageClass()); 1286 1287 // Merge "pure" flag. 1288 if (Old->isPure()) 1289 New->setPure(); 1290 1291 // Merge the "deleted" flag. 1292 if (Old->isDeleted()) 1293 New->setDeleted(); 1294 1295 if (getLangOptions().CPlusPlus) 1296 return MergeCXXFunctionDecl(New, Old); 1297 1298 return false; 1299} 1300 1301/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1302/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1303/// situation, merging decls or emitting diagnostics as appropriate. 1304/// 1305/// Tentative definition rules (C99 6.9.2p2) are checked by 1306/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1307/// definitions here, since the initializer hasn't been attached. 1308/// 1309void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1310 // If the new decl is already invalid, don't do any other checking. 1311 if (New->isInvalidDecl()) 1312 return; 1313 1314 // Verify the old decl was also a variable. 1315 VarDecl *Old = 0; 1316 if (!Previous.isSingleResult() || 1317 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1318 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1319 << New->getDeclName(); 1320 Diag(Previous.getRepresentativeDecl()->getLocation(), 1321 diag::note_previous_definition); 1322 return New->setInvalidDecl(); 1323 } 1324 1325 MergeAttributes(New, Old, Context); 1326 1327 // Merge the types 1328 QualType MergedT; 1329 if (getLangOptions().CPlusPlus) { 1330 if (Context.hasSameType(New->getType(), Old->getType())) 1331 MergedT = New->getType(); 1332 // C++ [basic.link]p10: 1333 // [...] the types specified by all declarations referring to a given 1334 // object or function shall be identical, except that declarations for an 1335 // array object can specify array types that differ by the presence or 1336 // absence of a major array bound (8.3.4). 1337 else if (Old->getType()->isIncompleteArrayType() && 1338 New->getType()->isArrayType()) { 1339 CanQual<ArrayType> OldArray 1340 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1341 CanQual<ArrayType> NewArray 1342 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1343 if (OldArray->getElementType() == NewArray->getElementType()) 1344 MergedT = New->getType(); 1345 } else if (Old->getType()->isArrayType() && 1346 New->getType()->isIncompleteArrayType()) { 1347 CanQual<ArrayType> OldArray 1348 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1349 CanQual<ArrayType> NewArray 1350 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1351 if (OldArray->getElementType() == NewArray->getElementType()) 1352 MergedT = Old->getType(); 1353 } 1354 } else { 1355 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1356 } 1357 if (MergedT.isNull()) { 1358 Diag(New->getLocation(), diag::err_redefinition_different_type) 1359 << New->getDeclName(); 1360 Diag(Old->getLocation(), diag::note_previous_definition); 1361 return New->setInvalidDecl(); 1362 } 1363 New->setType(MergedT); 1364 1365 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1366 if (New->getStorageClass() == VarDecl::Static && 1367 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1368 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1369 Diag(Old->getLocation(), diag::note_previous_definition); 1370 return New->setInvalidDecl(); 1371 } 1372 // C99 6.2.2p4: 1373 // For an identifier declared with the storage-class specifier 1374 // extern in a scope in which a prior declaration of that 1375 // identifier is visible,23) if the prior declaration specifies 1376 // internal or external linkage, the linkage of the identifier at 1377 // the later declaration is the same as the linkage specified at 1378 // the prior declaration. If no prior declaration is visible, or 1379 // if the prior declaration specifies no linkage, then the 1380 // identifier has external linkage. 1381 if (New->hasExternalStorage() && Old->hasLinkage()) 1382 /* Okay */; 1383 else if (New->getStorageClass() != VarDecl::Static && 1384 Old->getStorageClass() == VarDecl::Static) { 1385 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1386 Diag(Old->getLocation(), diag::note_previous_definition); 1387 return New->setInvalidDecl(); 1388 } 1389 1390 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1391 1392 // FIXME: The test for external storage here seems wrong? We still 1393 // need to check for mismatches. 1394 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1395 // Don't complain about out-of-line definitions of static members. 1396 !(Old->getLexicalDeclContext()->isRecord() && 1397 !New->getLexicalDeclContext()->isRecord())) { 1398 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1399 Diag(Old->getLocation(), diag::note_previous_definition); 1400 return New->setInvalidDecl(); 1401 } 1402 1403 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1404 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1405 Diag(Old->getLocation(), diag::note_previous_definition); 1406 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1407 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1408 Diag(Old->getLocation(), diag::note_previous_definition); 1409 } 1410 1411 // C++ doesn't have tentative definitions, so go right ahead and check here. 1412 const VarDecl *Def; 1413 if (getLangOptions().CPlusPlus && 1414 New->isThisDeclarationADefinition() == VarDecl::Definition && 1415 (Def = Old->getDefinition())) { 1416 Diag(New->getLocation(), diag::err_redefinition) 1417 << New->getDeclName(); 1418 Diag(Def->getLocation(), diag::note_previous_definition); 1419 New->setInvalidDecl(); 1420 return; 1421 } 1422 1423 // Keep a chain of previous declarations. 1424 New->setPreviousDeclaration(Old); 1425 1426 // Inherit access appropriately. 1427 New->setAccess(Old->getAccess()); 1428} 1429 1430/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1431/// no declarator (e.g. "struct foo;") is parsed. 1432Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1433 // FIXME: Error on auto/register at file scope 1434 // FIXME: Error on inline/virtual/explicit 1435 // FIXME: Warn on useless __thread 1436 // FIXME: Warn on useless const/volatile 1437 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1438 // FIXME: Warn on useless attributes 1439 Decl *TagD = 0; 1440 TagDecl *Tag = 0; 1441 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1442 DS.getTypeSpecType() == DeclSpec::TST_struct || 1443 DS.getTypeSpecType() == DeclSpec::TST_union || 1444 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1445 TagD = static_cast<Decl *>(DS.getTypeRep()); 1446 1447 if (!TagD) // We probably had an error 1448 return DeclPtrTy(); 1449 1450 // Note that the above type specs guarantee that the 1451 // type rep is a Decl, whereas in many of the others 1452 // it's a Type. 1453 Tag = dyn_cast<TagDecl>(TagD); 1454 } 1455 1456 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1457 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1458 // or incomplete types shall not be restrict-qualified." 1459 if (TypeQuals & DeclSpec::TQ_restrict) 1460 Diag(DS.getRestrictSpecLoc(), 1461 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1462 << DS.getSourceRange(); 1463 } 1464 1465 if (DS.isFriendSpecified()) { 1466 // If we're dealing with a class template decl, assume that the 1467 // template routines are handling it. 1468 if (TagD && isa<ClassTemplateDecl>(TagD)) 1469 return DeclPtrTy(); 1470 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1471 } 1472 1473 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1474 // If there are attributes in the DeclSpec, apply them to the record. 1475 if (const AttributeList *AL = DS.getAttributes()) 1476 ProcessDeclAttributeList(S, Record, AL); 1477 1478 if (!Record->getDeclName() && Record->isDefinition() && 1479 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1480 if (getLangOptions().CPlusPlus || 1481 Record->getDeclContext()->isRecord()) 1482 return BuildAnonymousStructOrUnion(S, DS, Record); 1483 1484 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1485 << DS.getSourceRange(); 1486 } 1487 1488 // Microsoft allows unnamed struct/union fields. Don't complain 1489 // about them. 1490 // FIXME: Should we support Microsoft's extensions in this area? 1491 if (Record->getDeclName() && getLangOptions().Microsoft) 1492 return DeclPtrTy::make(Tag); 1493 } 1494 1495 if (!DS.isMissingDeclaratorOk() && 1496 DS.getTypeSpecType() != DeclSpec::TST_error) { 1497 // Warn about typedefs of enums without names, since this is an 1498 // extension in both Microsoft an GNU. 1499 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1500 Tag && isa<EnumDecl>(Tag)) { 1501 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1502 << DS.getSourceRange(); 1503 return DeclPtrTy::make(Tag); 1504 } 1505 1506 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1507 << DS.getSourceRange(); 1508 } 1509 1510 return DeclPtrTy::make(Tag); 1511} 1512 1513/// We are trying to inject an anonymous member into the given scope; 1514/// check if there's an existing declaration that can't be overloaded. 1515/// 1516/// \return true if this is a forbidden redeclaration 1517static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1518 Scope *S, 1519 DeclContext *Owner, 1520 DeclarationName Name, 1521 SourceLocation NameLoc, 1522 unsigned diagnostic) { 1523 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1524 Sema::ForRedeclaration); 1525 if (!SemaRef.LookupName(R, S)) return false; 1526 1527 if (R.getAsSingle<TagDecl>()) 1528 return false; 1529 1530 // Pick a representative declaration. 1531 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1532 if (PrevDecl && Owner->isRecord()) { 1533 RecordDecl *Record = cast<RecordDecl>(Owner); 1534 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1535 return false; 1536 } 1537 1538 SemaRef.Diag(NameLoc, diagnostic) << Name; 1539 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1540 1541 return true; 1542} 1543 1544/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1545/// anonymous struct or union AnonRecord into the owning context Owner 1546/// and scope S. This routine will be invoked just after we realize 1547/// that an unnamed union or struct is actually an anonymous union or 1548/// struct, e.g., 1549/// 1550/// @code 1551/// union { 1552/// int i; 1553/// float f; 1554/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1555/// // f into the surrounding scope.x 1556/// @endcode 1557/// 1558/// This routine is recursive, injecting the names of nested anonymous 1559/// structs/unions into the owning context and scope as well. 1560bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1561 RecordDecl *AnonRecord) { 1562 unsigned diagKind 1563 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1564 : diag::err_anonymous_struct_member_redecl; 1565 1566 bool Invalid = false; 1567 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1568 FEnd = AnonRecord->field_end(); 1569 F != FEnd; ++F) { 1570 if ((*F)->getDeclName()) { 1571 if (CheckAnonMemberRedeclaration(*this, S, Owner, (*F)->getDeclName(), 1572 (*F)->getLocation(), diagKind)) { 1573 // C++ [class.union]p2: 1574 // The names of the members of an anonymous union shall be 1575 // distinct from the names of any other entity in the 1576 // scope in which the anonymous union is declared. 1577 Invalid = true; 1578 } else { 1579 // C++ [class.union]p2: 1580 // For the purpose of name lookup, after the anonymous union 1581 // definition, the members of the anonymous union are 1582 // considered to have been defined in the scope in which the 1583 // anonymous union is declared. 1584 Owner->makeDeclVisibleInContext(*F); 1585 S->AddDecl(DeclPtrTy::make(*F)); 1586 IdResolver.AddDecl(*F); 1587 } 1588 } else if (const RecordType *InnerRecordType 1589 = (*F)->getType()->getAs<RecordType>()) { 1590 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1591 if (InnerRecord->isAnonymousStructOrUnion()) 1592 Invalid = Invalid || 1593 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1594 } 1595 } 1596 1597 return Invalid; 1598} 1599 1600/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1601/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1602/// illegal input values are mapped to VarDecl::None. 1603static VarDecl::StorageClass 1604StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1605 switch (StorageClassSpec) { 1606 case DeclSpec::SCS_unspecified: return VarDecl::None; 1607 case DeclSpec::SCS_extern: return VarDecl::Extern; 1608 case DeclSpec::SCS_static: return VarDecl::Static; 1609 case DeclSpec::SCS_auto: return VarDecl::Auto; 1610 case DeclSpec::SCS_register: return VarDecl::Register; 1611 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1612 // Illegal SCSs map to None: error reporting is up to the caller. 1613 case DeclSpec::SCS_mutable: // Fall through. 1614 case DeclSpec::SCS_typedef: return VarDecl::None; 1615 } 1616 llvm_unreachable("unknown storage class specifier"); 1617} 1618 1619/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1620/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1621/// illegal input values are mapped to FunctionDecl::None. 1622static FunctionDecl::StorageClass 1623StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1624 switch (StorageClassSpec) { 1625 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1626 case DeclSpec::SCS_extern: return FunctionDecl::Extern; 1627 case DeclSpec::SCS_static: return FunctionDecl::Static; 1628 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1629 // Illegal SCSs map to None: error reporting is up to the caller. 1630 case DeclSpec::SCS_auto: // Fall through. 1631 case DeclSpec::SCS_mutable: // Fall through. 1632 case DeclSpec::SCS_register: // Fall through. 1633 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1634 } 1635 llvm_unreachable("unknown storage class specifier"); 1636} 1637 1638/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1639/// anonymous structure or union. Anonymous unions are a C++ feature 1640/// (C++ [class.union]) and a GNU C extension; anonymous structures 1641/// are a GNU C and GNU C++ extension. 1642Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1643 RecordDecl *Record) { 1644 DeclContext *Owner = Record->getDeclContext(); 1645 1646 // Diagnose whether this anonymous struct/union is an extension. 1647 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1648 Diag(Record->getLocation(), diag::ext_anonymous_union); 1649 else if (!Record->isUnion()) 1650 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1651 1652 // C and C++ require different kinds of checks for anonymous 1653 // structs/unions. 1654 bool Invalid = false; 1655 if (getLangOptions().CPlusPlus) { 1656 const char* PrevSpec = 0; 1657 unsigned DiagID; 1658 // C++ [class.union]p3: 1659 // Anonymous unions declared in a named namespace or in the 1660 // global namespace shall be declared static. 1661 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1662 (isa<TranslationUnitDecl>(Owner) || 1663 (isa<NamespaceDecl>(Owner) && 1664 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1665 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1666 Invalid = true; 1667 1668 // Recover by adding 'static'. 1669 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1670 PrevSpec, DiagID); 1671 } 1672 // C++ [class.union]p3: 1673 // A storage class is not allowed in a declaration of an 1674 // anonymous union in a class scope. 1675 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1676 isa<RecordDecl>(Owner)) { 1677 Diag(DS.getStorageClassSpecLoc(), 1678 diag::err_anonymous_union_with_storage_spec); 1679 Invalid = true; 1680 1681 // Recover by removing the storage specifier. 1682 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1683 PrevSpec, DiagID); 1684 } 1685 1686 // C++ [class.union]p2: 1687 // The member-specification of an anonymous union shall only 1688 // define non-static data members. [Note: nested types and 1689 // functions cannot be declared within an anonymous union. ] 1690 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1691 MemEnd = Record->decls_end(); 1692 Mem != MemEnd; ++Mem) { 1693 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1694 // C++ [class.union]p3: 1695 // An anonymous union shall not have private or protected 1696 // members (clause 11). 1697 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1698 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1699 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1700 Invalid = true; 1701 } 1702 } else if ((*Mem)->isImplicit()) { 1703 // Any implicit members are fine. 1704 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1705 // This is a type that showed up in an 1706 // elaborated-type-specifier inside the anonymous struct or 1707 // union, but which actually declares a type outside of the 1708 // anonymous struct or union. It's okay. 1709 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1710 if (!MemRecord->isAnonymousStructOrUnion() && 1711 MemRecord->getDeclName()) { 1712 // This is a nested type declaration. 1713 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1714 << (int)Record->isUnion(); 1715 Invalid = true; 1716 } 1717 } else { 1718 // We have something that isn't a non-static data 1719 // member. Complain about it. 1720 unsigned DK = diag::err_anonymous_record_bad_member; 1721 if (isa<TypeDecl>(*Mem)) 1722 DK = diag::err_anonymous_record_with_type; 1723 else if (isa<FunctionDecl>(*Mem)) 1724 DK = diag::err_anonymous_record_with_function; 1725 else if (isa<VarDecl>(*Mem)) 1726 DK = diag::err_anonymous_record_with_static; 1727 Diag((*Mem)->getLocation(), DK) 1728 << (int)Record->isUnion(); 1729 Invalid = true; 1730 } 1731 } 1732 } 1733 1734 if (!Record->isUnion() && !Owner->isRecord()) { 1735 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1736 << (int)getLangOptions().CPlusPlus; 1737 Invalid = true; 1738 } 1739 1740 // Mock up a declarator. 1741 Declarator Dc(DS, Declarator::TypeNameContext); 1742 TypeSourceInfo *TInfo = 0; 1743 GetTypeForDeclarator(Dc, S, &TInfo); 1744 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1745 1746 // Create a declaration for this anonymous struct/union. 1747 NamedDecl *Anon = 0; 1748 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1749 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1750 /*IdentifierInfo=*/0, 1751 Context.getTypeDeclType(Record), 1752 TInfo, 1753 /*BitWidth=*/0, /*Mutable=*/false); 1754 Anon->setAccess(AS_public); 1755 if (getLangOptions().CPlusPlus) 1756 FieldCollector->Add(cast<FieldDecl>(Anon)); 1757 } else { 1758 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1759 assert(SCSpec != DeclSpec::SCS_typedef && 1760 "Parser allowed 'typedef' as storage class VarDecl."); 1761 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1762 if (SCSpec == DeclSpec::SCS_mutable) { 1763 // mutable can only appear on non-static class members, so it's always 1764 // an error here 1765 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1766 Invalid = true; 1767 SC = VarDecl::None; 1768 } 1769 SCSpec = DS.getStorageClassSpecAsWritten(); 1770 VarDecl::StorageClass SCAsWritten 1771 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1772 1773 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1774 /*IdentifierInfo=*/0, 1775 Context.getTypeDeclType(Record), 1776 TInfo, SC, SCAsWritten); 1777 } 1778 Anon->setImplicit(); 1779 1780 // Add the anonymous struct/union object to the current 1781 // context. We'll be referencing this object when we refer to one of 1782 // its members. 1783 Owner->addDecl(Anon); 1784 1785 // Inject the members of the anonymous struct/union into the owning 1786 // context and into the identifier resolver chain for name lookup 1787 // purposes. 1788 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1789 Invalid = true; 1790 1791 // Mark this as an anonymous struct/union type. Note that we do not 1792 // do this until after we have already checked and injected the 1793 // members of this anonymous struct/union type, because otherwise 1794 // the members could be injected twice: once by DeclContext when it 1795 // builds its lookup table, and once by 1796 // InjectAnonymousStructOrUnionMembers. 1797 Record->setAnonymousStructOrUnion(true); 1798 1799 if (Invalid) 1800 Anon->setInvalidDecl(); 1801 1802 return DeclPtrTy::make(Anon); 1803} 1804 1805 1806/// GetNameForDeclarator - Determine the full declaration name for the 1807/// given Declarator. 1808DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1809 return GetNameFromUnqualifiedId(D.getName()); 1810} 1811 1812/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1813DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1814 switch (Name.getKind()) { 1815 case UnqualifiedId::IK_Identifier: 1816 return DeclarationName(Name.Identifier); 1817 1818 case UnqualifiedId::IK_OperatorFunctionId: 1819 return Context.DeclarationNames.getCXXOperatorName( 1820 Name.OperatorFunctionId.Operator); 1821 1822 case UnqualifiedId::IK_LiteralOperatorId: 1823 return Context.DeclarationNames.getCXXLiteralOperatorName( 1824 Name.Identifier); 1825 1826 case UnqualifiedId::IK_ConversionFunctionId: { 1827 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1828 if (Ty.isNull()) 1829 return DeclarationName(); 1830 1831 return Context.DeclarationNames.getCXXConversionFunctionName( 1832 Context.getCanonicalType(Ty)); 1833 } 1834 1835 case UnqualifiedId::IK_ConstructorName: { 1836 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1837 if (Ty.isNull()) 1838 return DeclarationName(); 1839 1840 return Context.DeclarationNames.getCXXConstructorName( 1841 Context.getCanonicalType(Ty)); 1842 } 1843 1844 case UnqualifiedId::IK_ConstructorTemplateId: { 1845 // In well-formed code, we can only have a constructor 1846 // template-id that refers to the current context, so go there 1847 // to find the actual type being constructed. 1848 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1849 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1850 return DeclarationName(); 1851 1852 // Determine the type of the class being constructed. 1853 QualType CurClassType = Context.getTypeDeclType(CurClass); 1854 1855 // FIXME: Check two things: that the template-id names the same type as 1856 // CurClassType, and that the template-id does not occur when the name 1857 // was qualified. 1858 1859 return Context.DeclarationNames.getCXXConstructorName( 1860 Context.getCanonicalType(CurClassType)); 1861 } 1862 1863 case UnqualifiedId::IK_DestructorName: { 1864 QualType Ty = GetTypeFromParser(Name.DestructorName); 1865 if (Ty.isNull()) 1866 return DeclarationName(); 1867 1868 return Context.DeclarationNames.getCXXDestructorName( 1869 Context.getCanonicalType(Ty)); 1870 } 1871 1872 case UnqualifiedId::IK_TemplateId: { 1873 TemplateName TName 1874 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1875 return Context.getNameForTemplate(TName); 1876 } 1877 } 1878 1879 assert(false && "Unknown name kind"); 1880 return DeclarationName(); 1881} 1882 1883/// isNearlyMatchingFunction - Determine whether the C++ functions 1884/// Declaration and Definition are "nearly" matching. This heuristic 1885/// is used to improve diagnostics in the case where an out-of-line 1886/// function definition doesn't match any declaration within 1887/// the class or namespace. 1888static bool isNearlyMatchingFunction(ASTContext &Context, 1889 FunctionDecl *Declaration, 1890 FunctionDecl *Definition) { 1891 if (Declaration->param_size() != Definition->param_size()) 1892 return false; 1893 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1894 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1895 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1896 1897 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1898 DefParamTy.getNonReferenceType())) 1899 return false; 1900 } 1901 1902 return true; 1903} 1904 1905Sema::DeclPtrTy 1906Sema::HandleDeclarator(Scope *S, Declarator &D, 1907 MultiTemplateParamsArg TemplateParamLists, 1908 bool IsFunctionDefinition) { 1909 DeclarationName Name = GetNameForDeclarator(D); 1910 1911 // All of these full declarators require an identifier. If it doesn't have 1912 // one, the ParsedFreeStandingDeclSpec action should be used. 1913 if (!Name) { 1914 if (!D.isInvalidType()) // Reject this if we think it is valid. 1915 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1916 diag::err_declarator_need_ident) 1917 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1918 return DeclPtrTy(); 1919 } 1920 1921 // The scope passed in may not be a decl scope. Zip up the scope tree until 1922 // we find one that is. 1923 while ((S->getFlags() & Scope::DeclScope) == 0 || 1924 (S->getFlags() & Scope::TemplateParamScope) != 0) 1925 S = S->getParent(); 1926 1927 // If this is an out-of-line definition of a member of a class template 1928 // or class template partial specialization, we may need to rebuild the 1929 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1930 // for more information. 1931 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1932 // handle expressions properly. 1933 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1934 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1935 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1936 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1937 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1938 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1939 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1940 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1941 // FIXME: Preserve type source info. 1942 QualType T = GetTypeFromParser(DS.getTypeRep()); 1943 1944 DeclContext *SavedContext = CurContext; 1945 CurContext = DC; 1946 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1947 CurContext = SavedContext; 1948 1949 if (T.isNull()) 1950 return DeclPtrTy(); 1951 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1952 } 1953 } 1954 1955 DeclContext *DC; 1956 NamedDecl *New; 1957 1958 TypeSourceInfo *TInfo = 0; 1959 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1960 1961 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1962 ForRedeclaration); 1963 1964 // See if this is a redefinition of a variable in the same scope. 1965 if (D.getCXXScopeSpec().isInvalid()) { 1966 DC = CurContext; 1967 D.setInvalidType(); 1968 } else if (!D.getCXXScopeSpec().isSet()) { 1969 bool IsLinkageLookup = false; 1970 1971 // If the declaration we're planning to build will be a function 1972 // or object with linkage, then look for another declaration with 1973 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1974 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1975 /* Do nothing*/; 1976 else if (R->isFunctionType()) { 1977 if (CurContext->isFunctionOrMethod() || 1978 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1979 IsLinkageLookup = true; 1980 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1981 IsLinkageLookup = true; 1982 else if (CurContext->getLookupContext()->isTranslationUnit() && 1983 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1984 IsLinkageLookup = true; 1985 1986 if (IsLinkageLookup) 1987 Previous.clear(LookupRedeclarationWithLinkage); 1988 1989 DC = CurContext; 1990 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1991 } else { // Something like "int foo::x;" 1992 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1993 1994 if (!DC) { 1995 // If we could not compute the declaration context, it's because the 1996 // declaration context is dependent but does not refer to a class, 1997 // class template, or class template partial specialization. Complain 1998 // and return early, to avoid the coming semantic disaster. 1999 Diag(D.getIdentifierLoc(), 2000 diag::err_template_qualified_declarator_no_match) 2001 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2002 << D.getCXXScopeSpec().getRange(); 2003 return DeclPtrTy(); 2004 } 2005 2006 if (!DC->isDependentContext() && 2007 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2008 return DeclPtrTy(); 2009 2010 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2011 Diag(D.getIdentifierLoc(), 2012 diag::err_member_def_undefined_record) 2013 << Name << DC << D.getCXXScopeSpec().getRange(); 2014 D.setInvalidType(); 2015 } 2016 2017 LookupQualifiedName(Previous, DC); 2018 2019 // Don't consider using declarations as previous declarations for 2020 // out-of-line members. 2021 RemoveUsingDecls(Previous); 2022 2023 // C++ 7.3.1.2p2: 2024 // Members (including explicit specializations of templates) of a named 2025 // namespace can also be defined outside that namespace by explicit 2026 // qualification of the name being defined, provided that the entity being 2027 // defined was already declared in the namespace and the definition appears 2028 // after the point of declaration in a namespace that encloses the 2029 // declarations namespace. 2030 // 2031 // Note that we only check the context at this point. We don't yet 2032 // have enough information to make sure that PrevDecl is actually 2033 // the declaration we want to match. For example, given: 2034 // 2035 // class X { 2036 // void f(); 2037 // void f(float); 2038 // }; 2039 // 2040 // void X::f(int) { } // ill-formed 2041 // 2042 // In this case, PrevDecl will point to the overload set 2043 // containing the two f's declared in X, but neither of them 2044 // matches. 2045 2046 // First check whether we named the global scope. 2047 if (isa<TranslationUnitDecl>(DC)) { 2048 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2049 << Name << D.getCXXScopeSpec().getRange(); 2050 } else { 2051 DeclContext *Cur = CurContext; 2052 while (isa<LinkageSpecDecl>(Cur)) 2053 Cur = Cur->getParent(); 2054 if (!Cur->Encloses(DC)) { 2055 // The qualifying scope doesn't enclose the original declaration. 2056 // Emit diagnostic based on current scope. 2057 SourceLocation L = D.getIdentifierLoc(); 2058 SourceRange R = D.getCXXScopeSpec().getRange(); 2059 if (isa<FunctionDecl>(Cur)) 2060 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2061 else 2062 Diag(L, diag::err_invalid_declarator_scope) 2063 << Name << cast<NamedDecl>(DC) << R; 2064 D.setInvalidType(); 2065 } 2066 } 2067 } 2068 2069 if (Previous.isSingleResult() && 2070 Previous.getFoundDecl()->isTemplateParameter()) { 2071 // Maybe we will complain about the shadowed template parameter. 2072 if (!D.isInvalidType()) 2073 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2074 Previous.getFoundDecl())) 2075 D.setInvalidType(); 2076 2077 // Just pretend that we didn't see the previous declaration. 2078 Previous.clear(); 2079 } 2080 2081 // In C++, the previous declaration we find might be a tag type 2082 // (class or enum). In this case, the new declaration will hide the 2083 // tag type. Note that this does does not apply if we're declaring a 2084 // typedef (C++ [dcl.typedef]p4). 2085 if (Previous.isSingleTagDecl() && 2086 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2087 Previous.clear(); 2088 2089 bool Redeclaration = false; 2090 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2091 if (TemplateParamLists.size()) { 2092 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2093 return DeclPtrTy(); 2094 } 2095 2096 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2097 } else if (R->isFunctionType()) { 2098 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2099 move(TemplateParamLists), 2100 IsFunctionDefinition, Redeclaration); 2101 } else { 2102 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2103 move(TemplateParamLists), 2104 Redeclaration); 2105 } 2106 2107 if (New == 0) 2108 return DeclPtrTy(); 2109 2110 // If this has an identifier and is not an invalid redeclaration or 2111 // function template specialization, add it to the scope stack. 2112 if (Name && !(Redeclaration && New->isInvalidDecl())) 2113 PushOnScopeChains(New, S); 2114 2115 return DeclPtrTy::make(New); 2116} 2117 2118/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2119/// types into constant array types in certain situations which would otherwise 2120/// be errors (for GCC compatibility). 2121static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2122 ASTContext &Context, 2123 bool &SizeIsNegative) { 2124 // This method tries to turn a variable array into a constant 2125 // array even when the size isn't an ICE. This is necessary 2126 // for compatibility with code that depends on gcc's buggy 2127 // constant expression folding, like struct {char x[(int)(char*)2];} 2128 SizeIsNegative = false; 2129 2130 QualifierCollector Qs; 2131 const Type *Ty = Qs.strip(T); 2132 2133 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2134 QualType Pointee = PTy->getPointeeType(); 2135 QualType FixedType = 2136 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2137 if (FixedType.isNull()) return FixedType; 2138 FixedType = Context.getPointerType(FixedType); 2139 return Qs.apply(FixedType); 2140 } 2141 2142 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2143 if (!VLATy) 2144 return QualType(); 2145 // FIXME: We should probably handle this case 2146 if (VLATy->getElementType()->isVariablyModifiedType()) 2147 return QualType(); 2148 2149 Expr::EvalResult EvalResult; 2150 if (!VLATy->getSizeExpr() || 2151 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2152 !EvalResult.Val.isInt()) 2153 return QualType(); 2154 2155 llvm::APSInt &Res = EvalResult.Val.getInt(); 2156 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2157 // TODO: preserve the size expression in declarator info 2158 return Context.getConstantArrayType(VLATy->getElementType(), 2159 Res, ArrayType::Normal, 0); 2160 } 2161 2162 SizeIsNegative = true; 2163 return QualType(); 2164} 2165 2166/// \brief Register the given locally-scoped external C declaration so 2167/// that it can be found later for redeclarations 2168void 2169Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2170 const LookupResult &Previous, 2171 Scope *S) { 2172 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2173 "Decl is not a locally-scoped decl!"); 2174 // Note that we have a locally-scoped external with this name. 2175 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2176 2177 if (!Previous.isSingleResult()) 2178 return; 2179 2180 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2181 2182 // If there was a previous declaration of this variable, it may be 2183 // in our identifier chain. Update the identifier chain with the new 2184 // declaration. 2185 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2186 // The previous declaration was found on the identifer resolver 2187 // chain, so remove it from its scope. 2188 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2189 S = S->getParent(); 2190 2191 if (S) 2192 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2193 } 2194} 2195 2196/// \brief Diagnose function specifiers on a declaration of an identifier that 2197/// does not identify a function. 2198void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2199 // FIXME: We should probably indicate the identifier in question to avoid 2200 // confusion for constructs like "inline int a(), b;" 2201 if (D.getDeclSpec().isInlineSpecified()) 2202 Diag(D.getDeclSpec().getInlineSpecLoc(), 2203 diag::err_inline_non_function); 2204 2205 if (D.getDeclSpec().isVirtualSpecified()) 2206 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2207 diag::err_virtual_non_function); 2208 2209 if (D.getDeclSpec().isExplicitSpecified()) 2210 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2211 diag::err_explicit_non_function); 2212} 2213 2214NamedDecl* 2215Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2216 QualType R, TypeSourceInfo *TInfo, 2217 LookupResult &Previous, bool &Redeclaration) { 2218 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2219 if (D.getCXXScopeSpec().isSet()) { 2220 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2221 << D.getCXXScopeSpec().getRange(); 2222 D.setInvalidType(); 2223 // Pretend we didn't see the scope specifier. 2224 DC = CurContext; 2225 Previous.clear(); 2226 } 2227 2228 if (getLangOptions().CPlusPlus) { 2229 // Check that there are no default arguments (C++ only). 2230 CheckExtraCXXDefaultArguments(D); 2231 } 2232 2233 DiagnoseFunctionSpecifiers(D); 2234 2235 if (D.getDeclSpec().isThreadSpecified()) 2236 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2237 2238 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2239 if (!NewTD) return 0; 2240 2241 // Handle attributes prior to checking for duplicates in MergeVarDecl 2242 ProcessDeclAttributes(S, NewTD, D); 2243 2244 // Merge the decl with the existing one if appropriate. If the decl is 2245 // in an outer scope, it isn't the same thing. 2246 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2247 if (!Previous.empty()) { 2248 Redeclaration = true; 2249 MergeTypeDefDecl(NewTD, Previous); 2250 } 2251 2252 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2253 // then it shall have block scope. 2254 QualType T = NewTD->getUnderlyingType(); 2255 if (T->isVariablyModifiedType()) { 2256 FunctionNeedsScopeChecking() = true; 2257 2258 if (S->getFnParent() == 0) { 2259 bool SizeIsNegative; 2260 QualType FixedTy = 2261 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2262 if (!FixedTy.isNull()) { 2263 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2264 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2265 } else { 2266 if (SizeIsNegative) 2267 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2268 else if (T->isVariableArrayType()) 2269 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2270 else 2271 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2272 NewTD->setInvalidDecl(); 2273 } 2274 } 2275 } 2276 2277 // If this is the C FILE type, notify the AST context. 2278 if (IdentifierInfo *II = NewTD->getIdentifier()) 2279 if (!NewTD->isInvalidDecl() && 2280 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2281 if (II->isStr("FILE")) 2282 Context.setFILEDecl(NewTD); 2283 else if (II->isStr("jmp_buf")) 2284 Context.setjmp_bufDecl(NewTD); 2285 else if (II->isStr("sigjmp_buf")) 2286 Context.setsigjmp_bufDecl(NewTD); 2287 } 2288 2289 return NewTD; 2290} 2291 2292/// \brief Determines whether the given declaration is an out-of-scope 2293/// previous declaration. 2294/// 2295/// This routine should be invoked when name lookup has found a 2296/// previous declaration (PrevDecl) that is not in the scope where a 2297/// new declaration by the same name is being introduced. If the new 2298/// declaration occurs in a local scope, previous declarations with 2299/// linkage may still be considered previous declarations (C99 2300/// 6.2.2p4-5, C++ [basic.link]p6). 2301/// 2302/// \param PrevDecl the previous declaration found by name 2303/// lookup 2304/// 2305/// \param DC the context in which the new declaration is being 2306/// declared. 2307/// 2308/// \returns true if PrevDecl is an out-of-scope previous declaration 2309/// for a new delcaration with the same name. 2310static bool 2311isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2312 ASTContext &Context) { 2313 if (!PrevDecl) 2314 return 0; 2315 2316 if (!PrevDecl->hasLinkage()) 2317 return false; 2318 2319 if (Context.getLangOptions().CPlusPlus) { 2320 // C++ [basic.link]p6: 2321 // If there is a visible declaration of an entity with linkage 2322 // having the same name and type, ignoring entities declared 2323 // outside the innermost enclosing namespace scope, the block 2324 // scope declaration declares that same entity and receives the 2325 // linkage of the previous declaration. 2326 DeclContext *OuterContext = DC->getLookupContext(); 2327 if (!OuterContext->isFunctionOrMethod()) 2328 // This rule only applies to block-scope declarations. 2329 return false; 2330 else { 2331 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2332 if (PrevOuterContext->isRecord()) 2333 // We found a member function: ignore it. 2334 return false; 2335 else { 2336 // Find the innermost enclosing namespace for the new and 2337 // previous declarations. 2338 while (!OuterContext->isFileContext()) 2339 OuterContext = OuterContext->getParent(); 2340 while (!PrevOuterContext->isFileContext()) 2341 PrevOuterContext = PrevOuterContext->getParent(); 2342 2343 // The previous declaration is in a different namespace, so it 2344 // isn't the same function. 2345 if (OuterContext->getPrimaryContext() != 2346 PrevOuterContext->getPrimaryContext()) 2347 return false; 2348 } 2349 } 2350 } 2351 2352 return true; 2353} 2354 2355static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2356 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2357 if (!SS.isSet()) return; 2358 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2359 SS.getRange()); 2360} 2361 2362NamedDecl* 2363Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2364 QualType R, TypeSourceInfo *TInfo, 2365 LookupResult &Previous, 2366 MultiTemplateParamsArg TemplateParamLists, 2367 bool &Redeclaration) { 2368 DeclarationName Name = GetNameForDeclarator(D); 2369 2370 // Check that there are no default arguments (C++ only). 2371 if (getLangOptions().CPlusPlus) 2372 CheckExtraCXXDefaultArguments(D); 2373 2374 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2375 assert(SCSpec != DeclSpec::SCS_typedef && 2376 "Parser allowed 'typedef' as storage class VarDecl."); 2377 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2378 if (SCSpec == DeclSpec::SCS_mutable) { 2379 // mutable can only appear on non-static class members, so it's always 2380 // an error here 2381 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2382 D.setInvalidType(); 2383 SC = VarDecl::None; 2384 } 2385 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2386 VarDecl::StorageClass SCAsWritten 2387 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2388 2389 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2390 if (!II) { 2391 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2392 << Name.getAsString(); 2393 return 0; 2394 } 2395 2396 DiagnoseFunctionSpecifiers(D); 2397 2398 if (!DC->isRecord() && S->getFnParent() == 0) { 2399 // C99 6.9p2: The storage-class specifiers auto and register shall not 2400 // appear in the declaration specifiers in an external declaration. 2401 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2402 2403 // If this is a register variable with an asm label specified, then this 2404 // is a GNU extension. 2405 if (SC == VarDecl::Register && D.getAsmLabel()) 2406 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2407 else 2408 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2409 D.setInvalidType(); 2410 } 2411 } 2412 if (DC->isRecord() && !CurContext->isRecord()) { 2413 // This is an out-of-line definition of a static data member. 2414 if (SC == VarDecl::Static) { 2415 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2416 diag::err_static_out_of_line) 2417 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2418 } else if (SC == VarDecl::None) 2419 SC = VarDecl::Static; 2420 } 2421 if (SC == VarDecl::Static) { 2422 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2423 if (RD->isLocalClass()) 2424 Diag(D.getIdentifierLoc(), 2425 diag::err_static_data_member_not_allowed_in_local_class) 2426 << Name << RD->getDeclName(); 2427 } 2428 } 2429 2430 // Match up the template parameter lists with the scope specifier, then 2431 // determine whether we have a template or a template specialization. 2432 bool isExplicitSpecialization = false; 2433 if (TemplateParameterList *TemplateParams 2434 = MatchTemplateParametersToScopeSpecifier( 2435 D.getDeclSpec().getSourceRange().getBegin(), 2436 D.getCXXScopeSpec(), 2437 (TemplateParameterList**)TemplateParamLists.get(), 2438 TemplateParamLists.size(), 2439 /*never a friend*/ false, 2440 isExplicitSpecialization)) { 2441 if (TemplateParams->size() > 0) { 2442 // There is no such thing as a variable template. 2443 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2444 << II 2445 << SourceRange(TemplateParams->getTemplateLoc(), 2446 TemplateParams->getRAngleLoc()); 2447 return 0; 2448 } else { 2449 // There is an extraneous 'template<>' for this variable. Complain 2450 // about it, but allow the declaration of the variable. 2451 Diag(TemplateParams->getTemplateLoc(), 2452 diag::err_template_variable_noparams) 2453 << II 2454 << SourceRange(TemplateParams->getTemplateLoc(), 2455 TemplateParams->getRAngleLoc()); 2456 2457 isExplicitSpecialization = true; 2458 } 2459 } 2460 2461 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2462 II, R, TInfo, SC, SCAsWritten); 2463 2464 if (D.isInvalidType()) 2465 NewVD->setInvalidDecl(); 2466 2467 SetNestedNameSpecifier(NewVD, D); 2468 2469 if (D.getDeclSpec().isThreadSpecified()) { 2470 if (NewVD->hasLocalStorage()) 2471 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2472 else if (!Context.Target.isTLSSupported()) 2473 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2474 else 2475 NewVD->setThreadSpecified(true); 2476 } 2477 2478 // Set the lexical context. If the declarator has a C++ scope specifier, the 2479 // lexical context will be different from the semantic context. 2480 NewVD->setLexicalDeclContext(CurContext); 2481 2482 // Handle attributes prior to checking for duplicates in MergeVarDecl 2483 ProcessDeclAttributes(S, NewVD, D); 2484 2485 // Handle GNU asm-label extension (encoded as an attribute). 2486 if (Expr *E = (Expr*) D.getAsmLabel()) { 2487 // The parser guarantees this is a string. 2488 StringLiteral *SE = cast<StringLiteral>(E); 2489 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2490 } 2491 2492 // Diagnose shadowed variables before filtering for scope. 2493 if (!D.getCXXScopeSpec().isSet()) 2494 CheckShadow(S, NewVD, Previous); 2495 2496 // Don't consider existing declarations that are in a different 2497 // scope and are out-of-semantic-context declarations (if the new 2498 // declaration has linkage). 2499 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2500 2501 // Merge the decl with the existing one if appropriate. 2502 if (!Previous.empty()) { 2503 if (Previous.isSingleResult() && 2504 isa<FieldDecl>(Previous.getFoundDecl()) && 2505 D.getCXXScopeSpec().isSet()) { 2506 // The user tried to define a non-static data member 2507 // out-of-line (C++ [dcl.meaning]p1). 2508 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2509 << D.getCXXScopeSpec().getRange(); 2510 Previous.clear(); 2511 NewVD->setInvalidDecl(); 2512 } 2513 } else if (D.getCXXScopeSpec().isSet()) { 2514 // No previous declaration in the qualifying scope. 2515 Diag(D.getIdentifierLoc(), diag::err_no_member) 2516 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2517 << D.getCXXScopeSpec().getRange(); 2518 NewVD->setInvalidDecl(); 2519 } 2520 2521 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2522 2523 // This is an explicit specialization of a static data member. Check it. 2524 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2525 CheckMemberSpecialization(NewVD, Previous)) 2526 NewVD->setInvalidDecl(); 2527 2528 // attributes declared post-definition are currently ignored 2529 if (Previous.isSingleResult()) { 2530 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2531 if (Def && (Def = Def->getDefinition()) && 2532 Def != NewVD && D.hasAttributes()) { 2533 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2534 Diag(Def->getLocation(), diag::note_previous_definition); 2535 } 2536 } 2537 2538 // If this is a locally-scoped extern C variable, update the map of 2539 // such variables. 2540 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2541 !NewVD->isInvalidDecl()) 2542 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2543 2544 return NewVD; 2545} 2546 2547/// \brief Diagnose variable or built-in function shadowing. Implements 2548/// -Wshadow. 2549/// 2550/// This method is called whenever a VarDecl is added to a "useful" 2551/// scope. 2552/// 2553/// \param S the scope in which the shadowing name is being declared 2554/// \param R the lookup of the name 2555/// 2556void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2557 // Return if warning is ignored. 2558 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2559 return; 2560 2561 // Don't diagnose declarations at file scope. The scope might not 2562 // have a DeclContext if (e.g.) we're parsing a function prototype. 2563 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2564 if (NewDC && NewDC->isFileContext()) 2565 return; 2566 2567 // Only diagnose if we're shadowing an unambiguous field or variable. 2568 if (R.getResultKind() != LookupResult::Found) 2569 return; 2570 2571 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2572 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2573 return; 2574 2575 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2576 2577 // Only warn about certain kinds of shadowing for class members. 2578 if (NewDC && NewDC->isRecord()) { 2579 // In particular, don't warn about shadowing non-class members. 2580 if (!OldDC->isRecord()) 2581 return; 2582 2583 // TODO: should we warn about static data members shadowing 2584 // static data members from base classes? 2585 2586 // TODO: don't diagnose for inaccessible shadowed members. 2587 // This is hard to do perfectly because we might friend the 2588 // shadowing context, but that's just a false negative. 2589 } 2590 2591 // Determine what kind of declaration we're shadowing. 2592 unsigned Kind; 2593 if (isa<RecordDecl>(OldDC)) { 2594 if (isa<FieldDecl>(ShadowedDecl)) 2595 Kind = 3; // field 2596 else 2597 Kind = 2; // static data member 2598 } else if (OldDC->isFileContext()) 2599 Kind = 1; // global 2600 else 2601 Kind = 0; // local 2602 2603 DeclarationName Name = R.getLookupName(); 2604 2605 // Emit warning and note. 2606 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2607 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2608} 2609 2610/// \brief Check -Wshadow without the advantage of a previous lookup. 2611void Sema::CheckShadow(Scope *S, VarDecl *D) { 2612 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2613 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2614 LookupName(R, S); 2615 CheckShadow(S, D, R); 2616} 2617 2618/// \brief Perform semantic checking on a newly-created variable 2619/// declaration. 2620/// 2621/// This routine performs all of the type-checking required for a 2622/// variable declaration once it has been built. It is used both to 2623/// check variables after they have been parsed and their declarators 2624/// have been translated into a declaration, and to check variables 2625/// that have been instantiated from a template. 2626/// 2627/// Sets NewVD->isInvalidDecl() if an error was encountered. 2628void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2629 LookupResult &Previous, 2630 bool &Redeclaration) { 2631 // If the decl is already known invalid, don't check it. 2632 if (NewVD->isInvalidDecl()) 2633 return; 2634 2635 QualType T = NewVD->getType(); 2636 2637 if (T->isObjCInterfaceType()) { 2638 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2639 return NewVD->setInvalidDecl(); 2640 } 2641 2642 // Emit an error if an address space was applied to decl with local storage. 2643 // This includes arrays of objects with address space qualifiers, but not 2644 // automatic variables that point to other address spaces. 2645 // ISO/IEC TR 18037 S5.1.2 2646 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2647 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2648 return NewVD->setInvalidDecl(); 2649 } 2650 2651 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2652 && !NewVD->hasAttr<BlocksAttr>()) 2653 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2654 2655 bool isVM = T->isVariablyModifiedType(); 2656 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2657 NewVD->hasAttr<BlocksAttr>() || 2658 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2659 // However, this turns on the scope checker for everything with a variable 2660 // which may impact compile time. See if we can find a better solution 2661 // to this, perhaps only checking functions that contain gotos in C++? 2662 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2663 FunctionNeedsScopeChecking() = true; 2664 2665 if ((isVM && NewVD->hasLinkage()) || 2666 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2667 bool SizeIsNegative; 2668 QualType FixedTy = 2669 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2670 2671 if (FixedTy.isNull() && T->isVariableArrayType()) { 2672 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2673 // FIXME: This won't give the correct result for 2674 // int a[10][n]; 2675 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2676 2677 if (NewVD->isFileVarDecl()) 2678 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2679 << SizeRange; 2680 else if (NewVD->getStorageClass() == VarDecl::Static) 2681 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2682 << SizeRange; 2683 else 2684 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2685 << SizeRange; 2686 return NewVD->setInvalidDecl(); 2687 } 2688 2689 if (FixedTy.isNull()) { 2690 if (NewVD->isFileVarDecl()) 2691 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2692 else 2693 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2694 return NewVD->setInvalidDecl(); 2695 } 2696 2697 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2698 NewVD->setType(FixedTy); 2699 } 2700 2701 if (Previous.empty() && NewVD->isExternC()) { 2702 // Since we did not find anything by this name and we're declaring 2703 // an extern "C" variable, look for a non-visible extern "C" 2704 // declaration with the same name. 2705 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2706 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2707 if (Pos != LocallyScopedExternalDecls.end()) 2708 Previous.addDecl(Pos->second); 2709 } 2710 2711 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2712 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2713 << T; 2714 return NewVD->setInvalidDecl(); 2715 } 2716 2717 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2718 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2719 return NewVD->setInvalidDecl(); 2720 } 2721 2722 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2723 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2724 return NewVD->setInvalidDecl(); 2725 } 2726 2727 if (!Previous.empty()) { 2728 Redeclaration = true; 2729 MergeVarDecl(NewVD, Previous); 2730 } 2731} 2732 2733/// \brief Data used with FindOverriddenMethod 2734struct FindOverriddenMethodData { 2735 Sema *S; 2736 CXXMethodDecl *Method; 2737}; 2738 2739/// \brief Member lookup function that determines whether a given C++ 2740/// method overrides a method in a base class, to be used with 2741/// CXXRecordDecl::lookupInBases(). 2742static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2743 CXXBasePath &Path, 2744 void *UserData) { 2745 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2746 2747 FindOverriddenMethodData *Data 2748 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2749 2750 DeclarationName Name = Data->Method->getDeclName(); 2751 2752 // FIXME: Do we care about other names here too? 2753 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2754 // We really want to find the base class constructor here. 2755 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2756 CanQualType CT = Data->S->Context.getCanonicalType(T); 2757 2758 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2759 } 2760 2761 for (Path.Decls = BaseRecord->lookup(Name); 2762 Path.Decls.first != Path.Decls.second; 2763 ++Path.Decls.first) { 2764 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2765 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2766 return true; 2767 } 2768 } 2769 2770 return false; 2771} 2772 2773/// AddOverriddenMethods - See if a method overrides any in the base classes, 2774/// and if so, check that it's a valid override and remember it. 2775void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2776 // Look for virtual methods in base classes that this method might override. 2777 CXXBasePaths Paths; 2778 FindOverriddenMethodData Data; 2779 Data.Method = MD; 2780 Data.S = this; 2781 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2782 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2783 E = Paths.found_decls_end(); I != E; ++I) { 2784 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2785 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2786 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2787 !CheckOverridingFunctionAttributes(MD, OldMD)) 2788 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2789 } 2790 } 2791 } 2792} 2793 2794NamedDecl* 2795Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2796 QualType R, TypeSourceInfo *TInfo, 2797 LookupResult &Previous, 2798 MultiTemplateParamsArg TemplateParamLists, 2799 bool IsFunctionDefinition, bool &Redeclaration) { 2800 assert(R.getTypePtr()->isFunctionType()); 2801 2802 DeclarationName Name = GetNameForDeclarator(D); 2803 FunctionDecl::StorageClass SC = FunctionDecl::None; 2804 switch (D.getDeclSpec().getStorageClassSpec()) { 2805 default: assert(0 && "Unknown storage class!"); 2806 case DeclSpec::SCS_auto: 2807 case DeclSpec::SCS_register: 2808 case DeclSpec::SCS_mutable: 2809 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2810 diag::err_typecheck_sclass_func); 2811 D.setInvalidType(); 2812 break; 2813 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2814 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2815 case DeclSpec::SCS_static: { 2816 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2817 // C99 6.7.1p5: 2818 // The declaration of an identifier for a function that has 2819 // block scope shall have no explicit storage-class specifier 2820 // other than extern 2821 // See also (C++ [dcl.stc]p4). 2822 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2823 diag::err_static_block_func); 2824 SC = FunctionDecl::None; 2825 } else 2826 SC = FunctionDecl::Static; 2827 break; 2828 } 2829 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2830 } 2831 2832 if (D.getDeclSpec().isThreadSpecified()) 2833 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2834 2835 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2836 bool isInline = D.getDeclSpec().isInlineSpecified(); 2837 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2838 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2839 2840 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2841 FunctionDecl::StorageClass SCAsWritten 2842 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 2843 2844 // Check that the return type is not an abstract class type. 2845 // For record types, this is done by the AbstractClassUsageDiagnoser once 2846 // the class has been completely parsed. 2847 if (!DC->isRecord() && 2848 RequireNonAbstractType(D.getIdentifierLoc(), 2849 R->getAs<FunctionType>()->getResultType(), 2850 diag::err_abstract_type_in_decl, 2851 AbstractReturnType)) 2852 D.setInvalidType(); 2853 2854 // Do not allow returning a objc interface by-value. 2855 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2856 Diag(D.getIdentifierLoc(), 2857 diag::err_object_cannot_be_passed_returned_by_value) << 0 2858 << R->getAs<FunctionType>()->getResultType(); 2859 D.setInvalidType(); 2860 } 2861 2862 bool isVirtualOkay = false; 2863 FunctionDecl *NewFD; 2864 2865 if (isFriend) { 2866 // C++ [class.friend]p5 2867 // A function can be defined in a friend declaration of a 2868 // class . . . . Such a function is implicitly inline. 2869 isInline |= IsFunctionDefinition; 2870 } 2871 2872 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2873 // This is a C++ constructor declaration. 2874 assert(DC->isRecord() && 2875 "Constructors can only be declared in a member context"); 2876 2877 R = CheckConstructorDeclarator(D, R, SC); 2878 2879 // Create the new declaration 2880 NewFD = CXXConstructorDecl::Create(Context, 2881 cast<CXXRecordDecl>(DC), 2882 D.getIdentifierLoc(), Name, R, TInfo, 2883 isExplicit, isInline, 2884 /*isImplicitlyDeclared=*/false); 2885 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2886 // This is a C++ destructor declaration. 2887 if (DC->isRecord()) { 2888 R = CheckDestructorDeclarator(D, SC); 2889 2890 NewFD = CXXDestructorDecl::Create(Context, 2891 cast<CXXRecordDecl>(DC), 2892 D.getIdentifierLoc(), Name, R, 2893 isInline, 2894 /*isImplicitlyDeclared=*/false); 2895 NewFD->setTypeSourceInfo(TInfo); 2896 2897 isVirtualOkay = true; 2898 } else { 2899 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2900 2901 // Create a FunctionDecl to satisfy the function definition parsing 2902 // code path. 2903 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2904 Name, R, TInfo, SC, SCAsWritten, isInline, 2905 /*hasPrototype=*/true); 2906 D.setInvalidType(); 2907 } 2908 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2909 if (!DC->isRecord()) { 2910 Diag(D.getIdentifierLoc(), 2911 diag::err_conv_function_not_member); 2912 return 0; 2913 } 2914 2915 CheckConversionDeclarator(D, R, SC); 2916 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2917 D.getIdentifierLoc(), Name, R, TInfo, 2918 isInline, isExplicit); 2919 2920 isVirtualOkay = true; 2921 } else if (DC->isRecord()) { 2922 // If the of the function is the same as the name of the record, then this 2923 // must be an invalid constructor that has a return type. 2924 // (The parser checks for a return type and makes the declarator a 2925 // constructor if it has no return type). 2926 // must have an invalid constructor that has a return type 2927 if (Name.getAsIdentifierInfo() && 2928 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2929 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2930 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2931 << SourceRange(D.getIdentifierLoc()); 2932 return 0; 2933 } 2934 2935 bool isStatic = SC == FunctionDecl::Static; 2936 2937 // [class.free]p1: 2938 // Any allocation function for a class T is a static member 2939 // (even if not explicitly declared static). 2940 if (Name.getCXXOverloadedOperator() == OO_New || 2941 Name.getCXXOverloadedOperator() == OO_Array_New) 2942 isStatic = true; 2943 2944 // [class.free]p6 Any deallocation function for a class X is a static member 2945 // (even if not explicitly declared static). 2946 if (Name.getCXXOverloadedOperator() == OO_Delete || 2947 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2948 isStatic = true; 2949 2950 // This is a C++ method declaration. 2951 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2952 D.getIdentifierLoc(), Name, R, TInfo, 2953 isStatic, SCAsWritten, isInline); 2954 2955 isVirtualOkay = !isStatic; 2956 } else { 2957 // Determine whether the function was written with a 2958 // prototype. This true when: 2959 // - we're in C++ (where every function has a prototype), 2960 // - there is a prototype in the declarator, or 2961 // - the type R of the function is some kind of typedef or other reference 2962 // to a type name (which eventually refers to a function type). 2963 bool HasPrototype = 2964 getLangOptions().CPlusPlus || 2965 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2966 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2967 2968 NewFD = FunctionDecl::Create(Context, DC, 2969 D.getIdentifierLoc(), 2970 Name, R, TInfo, SC, SCAsWritten, isInline, 2971 HasPrototype); 2972 } 2973 2974 if (D.isInvalidType()) 2975 NewFD->setInvalidDecl(); 2976 2977 SetNestedNameSpecifier(NewFD, D); 2978 2979 // Set the lexical context. If the declarator has a C++ 2980 // scope specifier, or is the object of a friend declaration, the 2981 // lexical context will be different from the semantic context. 2982 NewFD->setLexicalDeclContext(CurContext); 2983 2984 // Match up the template parameter lists with the scope specifier, then 2985 // determine whether we have a template or a template specialization. 2986 FunctionTemplateDecl *FunctionTemplate = 0; 2987 bool isExplicitSpecialization = false; 2988 bool isFunctionTemplateSpecialization = false; 2989 if (TemplateParameterList *TemplateParams 2990 = MatchTemplateParametersToScopeSpecifier( 2991 D.getDeclSpec().getSourceRange().getBegin(), 2992 D.getCXXScopeSpec(), 2993 (TemplateParameterList**)TemplateParamLists.get(), 2994 TemplateParamLists.size(), 2995 isFriend, 2996 isExplicitSpecialization)) { 2997 if (TemplateParams->size() > 0) { 2998 // This is a function template 2999 3000 // Check that we can declare a template here. 3001 if (CheckTemplateDeclScope(S, TemplateParams)) 3002 return 0; 3003 3004 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3005 NewFD->getLocation(), 3006 Name, TemplateParams, 3007 NewFD); 3008 FunctionTemplate->setLexicalDeclContext(CurContext); 3009 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3010 } else { 3011 // This is a function template specialization. 3012 isFunctionTemplateSpecialization = true; 3013 3014 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3015 if (isFriend && isFunctionTemplateSpecialization) { 3016 // We want to remove the "template<>", found here. 3017 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3018 3019 // If we remove the template<> and the name is not a 3020 // template-id, we're actually silently creating a problem: 3021 // the friend declaration will refer to an untemplated decl, 3022 // and clearly the user wants a template specialization. So 3023 // we need to insert '<>' after the name. 3024 SourceLocation InsertLoc; 3025 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3026 InsertLoc = D.getName().getSourceRange().getEnd(); 3027 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3028 } 3029 3030 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3031 << Name << RemoveRange 3032 << FixItHint::CreateRemoval(RemoveRange) 3033 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3034 } 3035 } 3036 3037 // FIXME: Free this memory properly. 3038 TemplateParamLists.release(); 3039 } 3040 3041 // C++ [dcl.fct.spec]p5: 3042 // The virtual specifier shall only be used in declarations of 3043 // nonstatic class member functions that appear within a 3044 // member-specification of a class declaration; see 10.3. 3045 // 3046 if (isVirtual && !NewFD->isInvalidDecl()) { 3047 if (!isVirtualOkay) { 3048 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3049 diag::err_virtual_non_function); 3050 } else if (!CurContext->isRecord()) { 3051 // 'virtual' was specified outside of the class. 3052 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3053 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3054 } else { 3055 // Okay: Add virtual to the method. 3056 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3057 CurClass->setMethodAsVirtual(NewFD); 3058 } 3059 } 3060 3061 // C++ [dcl.fct.spec]p6: 3062 // The explicit specifier shall be used only in the declaration of a 3063 // constructor or conversion function within its class definition; see 12.3.1 3064 // and 12.3.2. 3065 if (isExplicit && !NewFD->isInvalidDecl()) { 3066 if (!CurContext->isRecord()) { 3067 // 'explicit' was specified outside of the class. 3068 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3069 diag::err_explicit_out_of_class) 3070 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3071 } else if (!isa<CXXConstructorDecl>(NewFD) && 3072 !isa<CXXConversionDecl>(NewFD)) { 3073 // 'explicit' was specified on a function that wasn't a constructor 3074 // or conversion function. 3075 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3076 diag::err_explicit_non_ctor_or_conv_function) 3077 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3078 } 3079 } 3080 3081 // Filter out previous declarations that don't match the scope. 3082 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3083 3084 if (isFriend) { 3085 // DC is the namespace in which the function is being declared. 3086 assert((DC->isFileContext() || !Previous.empty()) && 3087 "previously-undeclared friend function being created " 3088 "in a non-namespace context"); 3089 3090 // For now, claim that the objects have no previous declaration. 3091 if (FunctionTemplate) { 3092 FunctionTemplate->setObjectOfFriendDecl(false); 3093 FunctionTemplate->setAccess(AS_public); 3094 } 3095 NewFD->setObjectOfFriendDecl(false); 3096 NewFD->setAccess(AS_public); 3097 } 3098 3099 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3100 !CurContext->isRecord()) { 3101 // C++ [class.static]p1: 3102 // A data or function member of a class may be declared static 3103 // in a class definition, in which case it is a static member of 3104 // the class. 3105 3106 // Complain about the 'static' specifier if it's on an out-of-line 3107 // member function definition. 3108 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3109 diag::err_static_out_of_line) 3110 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3111 } 3112 3113 // Handle GNU asm-label extension (encoded as an attribute). 3114 if (Expr *E = (Expr*) D.getAsmLabel()) { 3115 // The parser guarantees this is a string. 3116 StringLiteral *SE = cast<StringLiteral>(E); 3117 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3118 } 3119 3120 // Copy the parameter declarations from the declarator D to the function 3121 // declaration NewFD, if they are available. First scavenge them into Params. 3122 llvm::SmallVector<ParmVarDecl*, 16> Params; 3123 if (D.getNumTypeObjects() > 0) { 3124 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3125 3126 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3127 // function that takes no arguments, not a function that takes a 3128 // single void argument. 3129 // We let through "const void" here because Sema::GetTypeForDeclarator 3130 // already checks for that case. 3131 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3132 FTI.ArgInfo[0].Param && 3133 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3134 // Empty arg list, don't push any params. 3135 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3136 3137 // In C++, the empty parameter-type-list must be spelled "void"; a 3138 // typedef of void is not permitted. 3139 if (getLangOptions().CPlusPlus && 3140 Param->getType().getUnqualifiedType() != Context.VoidTy) 3141 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3142 // FIXME: Leaks decl? 3143 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3144 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3145 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3146 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3147 Param->setDeclContext(NewFD); 3148 Params.push_back(Param); 3149 3150 if (Param->isInvalidDecl()) 3151 NewFD->setInvalidDecl(); 3152 } 3153 } 3154 3155 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3156 // When we're declaring a function with a typedef, typeof, etc as in the 3157 // following example, we'll need to synthesize (unnamed) 3158 // parameters for use in the declaration. 3159 // 3160 // @code 3161 // typedef void fn(int); 3162 // fn f; 3163 // @endcode 3164 3165 // Synthesize a parameter for each argument type. 3166 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3167 AE = FT->arg_type_end(); AI != AE; ++AI) { 3168 ParmVarDecl *Param = ParmVarDecl::Create(Context, NewFD, 3169 SourceLocation(), 0, 3170 *AI, /*TInfo=*/0, 3171 VarDecl::None, 3172 VarDecl::None, 0); 3173 Param->setImplicit(); 3174 Params.push_back(Param); 3175 } 3176 } else { 3177 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3178 "Should not need args for typedef of non-prototype fn"); 3179 } 3180 // Finally, we know we have the right number of parameters, install them. 3181 NewFD->setParams(Params.data(), Params.size()); 3182 3183 // If the declarator is a template-id, translate the parser's template 3184 // argument list into our AST format. 3185 bool HasExplicitTemplateArgs = false; 3186 TemplateArgumentListInfo TemplateArgs; 3187 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3188 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3189 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3190 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3191 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3192 TemplateId->getTemplateArgs(), 3193 TemplateId->NumArgs); 3194 translateTemplateArguments(TemplateArgsPtr, 3195 TemplateArgs); 3196 TemplateArgsPtr.release(); 3197 3198 HasExplicitTemplateArgs = true; 3199 3200 if (FunctionTemplate) { 3201 // FIXME: Diagnose function template with explicit template 3202 // arguments. 3203 HasExplicitTemplateArgs = false; 3204 } else if (!isFunctionTemplateSpecialization && 3205 !D.getDeclSpec().isFriendSpecified()) { 3206 // We have encountered something that the user meant to be a 3207 // specialization (because it has explicitly-specified template 3208 // arguments) but that was not introduced with a "template<>" (or had 3209 // too few of them). 3210 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3211 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3212 << FixItHint::CreateInsertion( 3213 D.getDeclSpec().getSourceRange().getBegin(), 3214 "template<> "); 3215 isFunctionTemplateSpecialization = true; 3216 } else { 3217 // "friend void foo<>(int);" is an implicit specialization decl. 3218 isFunctionTemplateSpecialization = true; 3219 } 3220 } else if (isFriend && isFunctionTemplateSpecialization) { 3221 // This combination is only possible in a recovery case; the user 3222 // wrote something like: 3223 // template <> friend void foo(int); 3224 // which we're recovering from as if the user had written: 3225 // friend void foo<>(int); 3226 // Go ahead and fake up a template id. 3227 HasExplicitTemplateArgs = true; 3228 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3229 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3230 } 3231 3232 // If it's a friend (and only if it's a friend), it's possible 3233 // that either the specialized function type or the specialized 3234 // template is dependent, and therefore matching will fail. In 3235 // this case, don't check the specialization yet. 3236 if (isFunctionTemplateSpecialization && isFriend && 3237 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3238 assert(HasExplicitTemplateArgs && 3239 "friend function specialization without template args"); 3240 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3241 Previous)) 3242 NewFD->setInvalidDecl(); 3243 } else if (isFunctionTemplateSpecialization) { 3244 if (CheckFunctionTemplateSpecialization(NewFD, 3245 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3246 Previous)) 3247 NewFD->setInvalidDecl(); 3248 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3249 if (CheckMemberSpecialization(NewFD, Previous)) 3250 NewFD->setInvalidDecl(); 3251 } 3252 3253 // Perform semantic checking on the function declaration. 3254 bool OverloadableAttrRequired = false; // FIXME: HACK! 3255 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3256 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3257 3258 assert((NewFD->isInvalidDecl() || !Redeclaration || 3259 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3260 "previous declaration set still overloaded"); 3261 3262 NamedDecl *PrincipalDecl = (FunctionTemplate 3263 ? cast<NamedDecl>(FunctionTemplate) 3264 : NewFD); 3265 3266 if (isFriend && Redeclaration) { 3267 AccessSpecifier Access = AS_public; 3268 if (!NewFD->isInvalidDecl()) 3269 Access = NewFD->getPreviousDeclaration()->getAccess(); 3270 3271 NewFD->setAccess(Access); 3272 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3273 3274 PrincipalDecl->setObjectOfFriendDecl(true); 3275 } 3276 3277 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3278 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3279 PrincipalDecl->setNonMemberOperator(); 3280 3281 // If we have a function template, check the template parameter 3282 // list. This will check and merge default template arguments. 3283 if (FunctionTemplate) { 3284 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3285 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3286 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3287 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3288 : TPC_FunctionTemplate); 3289 } 3290 3291 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3292 // Fake up an access specifier if it's supposed to be a class member. 3293 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3294 NewFD->setAccess(AS_public); 3295 3296 // An out-of-line member function declaration must also be a 3297 // definition (C++ [dcl.meaning]p1). 3298 // Note that this is not the case for explicit specializations of 3299 // function templates or member functions of class templates, per 3300 // C++ [temp.expl.spec]p2. 3301 if (!IsFunctionDefinition && !isFriend && 3302 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3303 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3304 << D.getCXXScopeSpec().getRange(); 3305 NewFD->setInvalidDecl(); 3306 } else if (!Redeclaration && 3307 !(isFriend && CurContext->isDependentContext())) { 3308 // The user tried to provide an out-of-line definition for a 3309 // function that is a member of a class or namespace, but there 3310 // was no such member function declared (C++ [class.mfct]p2, 3311 // C++ [namespace.memdef]p2). For example: 3312 // 3313 // class X { 3314 // void f() const; 3315 // }; 3316 // 3317 // void X::f() { } // ill-formed 3318 // 3319 // Complain about this problem, and attempt to suggest close 3320 // matches (e.g., those that differ only in cv-qualifiers and 3321 // whether the parameter types are references). 3322 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3323 << Name << DC << D.getCXXScopeSpec().getRange(); 3324 NewFD->setInvalidDecl(); 3325 3326 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3327 ForRedeclaration); 3328 LookupQualifiedName(Prev, DC); 3329 assert(!Prev.isAmbiguous() && 3330 "Cannot have an ambiguity in previous-declaration lookup"); 3331 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3332 Func != FuncEnd; ++Func) { 3333 if (isa<FunctionDecl>(*Func) && 3334 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3335 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3336 } 3337 } 3338 } 3339 3340 // Handle attributes. We need to have merged decls when handling attributes 3341 // (for example to check for conflicts, etc). 3342 // FIXME: This needs to happen before we merge declarations. Then, 3343 // let attribute merging cope with attribute conflicts. 3344 ProcessDeclAttributes(S, NewFD, D); 3345 3346 // attributes declared post-definition are currently ignored 3347 if (Redeclaration && Previous.isSingleResult()) { 3348 const FunctionDecl *Def; 3349 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3350 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3351 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3352 Diag(Def->getLocation(), diag::note_previous_definition); 3353 } 3354 } 3355 3356 AddKnownFunctionAttributes(NewFD); 3357 3358 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3359 // If a function name is overloadable in C, then every function 3360 // with that name must be marked "overloadable". 3361 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3362 << Redeclaration << NewFD; 3363 if (!Previous.empty()) 3364 Diag(Previous.getRepresentativeDecl()->getLocation(), 3365 diag::note_attribute_overloadable_prev_overload); 3366 NewFD->addAttr(::new (Context) OverloadableAttr()); 3367 } 3368 3369 // If this is a locally-scoped extern C function, update the 3370 // map of such names. 3371 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3372 && !NewFD->isInvalidDecl()) 3373 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3374 3375 // Set this FunctionDecl's range up to the right paren. 3376 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3377 3378 if (FunctionTemplate && NewFD->isInvalidDecl()) 3379 FunctionTemplate->setInvalidDecl(); 3380 3381 if (FunctionTemplate) 3382 return FunctionTemplate; 3383 3384 3385 // Keep track of static, non-inlined function definitions that 3386 // have not been used. We will warn later. 3387 // FIXME: Also include static functions declared but not defined. 3388 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3389 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3390 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3391 && !NewFD->hasAttr<ConstructorAttr>() 3392 && !NewFD->hasAttr<DestructorAttr>()) 3393 UnusedStaticFuncs.push_back(NewFD); 3394 3395 return NewFD; 3396} 3397 3398/// \brief Perform semantic checking of a new function declaration. 3399/// 3400/// Performs semantic analysis of the new function declaration 3401/// NewFD. This routine performs all semantic checking that does not 3402/// require the actual declarator involved in the declaration, and is 3403/// used both for the declaration of functions as they are parsed 3404/// (called via ActOnDeclarator) and for the declaration of functions 3405/// that have been instantiated via C++ template instantiation (called 3406/// via InstantiateDecl). 3407/// 3408/// \param IsExplicitSpecialiation whether this new function declaration is 3409/// an explicit specialization of the previous declaration. 3410/// 3411/// This sets NewFD->isInvalidDecl() to true if there was an error. 3412void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3413 LookupResult &Previous, 3414 bool IsExplicitSpecialization, 3415 bool &Redeclaration, 3416 bool &OverloadableAttrRequired) { 3417 // If NewFD is already known erroneous, don't do any of this checking. 3418 if (NewFD->isInvalidDecl()) 3419 return; 3420 3421 if (NewFD->getResultType()->isVariablyModifiedType()) { 3422 // Functions returning a variably modified type violate C99 6.7.5.2p2 3423 // because all functions have linkage. 3424 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3425 return NewFD->setInvalidDecl(); 3426 } 3427 3428 if (NewFD->isMain()) 3429 CheckMain(NewFD); 3430 3431 // Check for a previous declaration of this name. 3432 if (Previous.empty() && NewFD->isExternC()) { 3433 // Since we did not find anything by this name and we're declaring 3434 // an extern "C" function, look for a non-visible extern "C" 3435 // declaration with the same name. 3436 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3437 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3438 if (Pos != LocallyScopedExternalDecls.end()) 3439 Previous.addDecl(Pos->second); 3440 } 3441 3442 // Merge or overload the declaration with an existing declaration of 3443 // the same name, if appropriate. 3444 if (!Previous.empty()) { 3445 // Determine whether NewFD is an overload of PrevDecl or 3446 // a declaration that requires merging. If it's an overload, 3447 // there's no more work to do here; we'll just add the new 3448 // function to the scope. 3449 3450 NamedDecl *OldDecl = 0; 3451 if (!AllowOverloadingOfFunction(Previous, Context)) { 3452 Redeclaration = true; 3453 OldDecl = Previous.getFoundDecl(); 3454 } else { 3455 if (!getLangOptions().CPlusPlus) { 3456 OverloadableAttrRequired = true; 3457 3458 // Functions marked "overloadable" must have a prototype (that 3459 // we can't get through declaration merging). 3460 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3461 Diag(NewFD->getLocation(), 3462 diag::err_attribute_overloadable_no_prototype) 3463 << NewFD; 3464 Redeclaration = true; 3465 3466 // Turn this into a variadic function with no parameters. 3467 QualType R = Context.getFunctionType( 3468 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3469 0, 0, true, 0, false, false, 0, 0, 3470 FunctionType::ExtInfo()); 3471 NewFD->setType(R); 3472 return NewFD->setInvalidDecl(); 3473 } 3474 } 3475 3476 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3477 case Ovl_Match: 3478 Redeclaration = true; 3479 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3480 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3481 Redeclaration = false; 3482 } 3483 break; 3484 3485 case Ovl_NonFunction: 3486 Redeclaration = true; 3487 break; 3488 3489 case Ovl_Overload: 3490 Redeclaration = false; 3491 break; 3492 } 3493 } 3494 3495 if (Redeclaration) { 3496 // NewFD and OldDecl represent declarations that need to be 3497 // merged. 3498 if (MergeFunctionDecl(NewFD, OldDecl)) 3499 return NewFD->setInvalidDecl(); 3500 3501 Previous.clear(); 3502 Previous.addDecl(OldDecl); 3503 3504 if (FunctionTemplateDecl *OldTemplateDecl 3505 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3506 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3507 FunctionTemplateDecl *NewTemplateDecl 3508 = NewFD->getDescribedFunctionTemplate(); 3509 assert(NewTemplateDecl && "Template/non-template mismatch"); 3510 if (CXXMethodDecl *Method 3511 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3512 Method->setAccess(OldTemplateDecl->getAccess()); 3513 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3514 } 3515 3516 // If this is an explicit specialization of a member that is a function 3517 // template, mark it as a member specialization. 3518 if (IsExplicitSpecialization && 3519 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3520 NewTemplateDecl->setMemberSpecialization(); 3521 assert(OldTemplateDecl->isMemberSpecialization()); 3522 } 3523 } else { 3524 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3525 NewFD->setAccess(OldDecl->getAccess()); 3526 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3527 } 3528 } 3529 } 3530 3531 // Semantic checking for this function declaration (in isolation). 3532 if (getLangOptions().CPlusPlus) { 3533 // C++-specific checks. 3534 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3535 CheckConstructor(Constructor); 3536 } else if (CXXDestructorDecl *Destructor = 3537 dyn_cast<CXXDestructorDecl>(NewFD)) { 3538 CXXRecordDecl *Record = Destructor->getParent(); 3539 QualType ClassType = Context.getTypeDeclType(Record); 3540 3541 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3542 // type is dependent? Both gcc and edg can handle that. 3543 if (!ClassType->isDependentType()) { 3544 DeclarationName Name 3545 = Context.DeclarationNames.getCXXDestructorName( 3546 Context.getCanonicalType(ClassType)); 3547 if (NewFD->getDeclName() != Name) { 3548 Diag(NewFD->getLocation(), diag::err_destructor_name); 3549 return NewFD->setInvalidDecl(); 3550 } 3551 } 3552 3553 Record->setUserDeclaredDestructor(true); 3554 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3555 // user-defined destructor. 3556 Record->setPOD(false); 3557 3558 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3559 // declared destructor. 3560 // FIXME: C++0x: don't do this for "= default" destructors 3561 Record->setHasTrivialDestructor(false); 3562 } else if (CXXConversionDecl *Conversion 3563 = dyn_cast<CXXConversionDecl>(NewFD)) { 3564 ActOnConversionDeclarator(Conversion); 3565 } 3566 3567 // Find any virtual functions that this function overrides. 3568 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3569 if (!Method->isFunctionTemplateSpecialization() && 3570 !Method->getDescribedFunctionTemplate()) 3571 AddOverriddenMethods(Method->getParent(), Method); 3572 } 3573 3574 // Additional checks for the destructor; make sure we do this after we 3575 // figure out whether the destructor is virtual. 3576 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3577 if (!Destructor->getParent()->isDependentType()) 3578 CheckDestructor(Destructor); 3579 3580 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3581 if (NewFD->isOverloadedOperator() && 3582 CheckOverloadedOperatorDeclaration(NewFD)) 3583 return NewFD->setInvalidDecl(); 3584 3585 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3586 if (NewFD->getLiteralIdentifier() && 3587 CheckLiteralOperatorDeclaration(NewFD)) 3588 return NewFD->setInvalidDecl(); 3589 3590 // In C++, check default arguments now that we have merged decls. Unless 3591 // the lexical context is the class, because in this case this is done 3592 // during delayed parsing anyway. 3593 if (!CurContext->isRecord()) 3594 CheckCXXDefaultArguments(NewFD); 3595 } 3596} 3597 3598void Sema::CheckMain(FunctionDecl* FD) { 3599 // C++ [basic.start.main]p3: A program that declares main to be inline 3600 // or static is ill-formed. 3601 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3602 // shall not appear in a declaration of main. 3603 // static main is not an error under C99, but we should warn about it. 3604 bool isInline = FD->isInlineSpecified(); 3605 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3606 if (isInline || isStatic) { 3607 unsigned diagID = diag::warn_unusual_main_decl; 3608 if (isInline || getLangOptions().CPlusPlus) 3609 diagID = diag::err_unusual_main_decl; 3610 3611 int which = isStatic + (isInline << 1) - 1; 3612 Diag(FD->getLocation(), diagID) << which; 3613 } 3614 3615 QualType T = FD->getType(); 3616 assert(T->isFunctionType() && "function decl is not of function type"); 3617 const FunctionType* FT = T->getAs<FunctionType>(); 3618 3619 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3620 // TODO: add a replacement fixit to turn the return type into 'int'. 3621 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3622 FD->setInvalidDecl(true); 3623 } 3624 3625 // Treat protoless main() as nullary. 3626 if (isa<FunctionNoProtoType>(FT)) return; 3627 3628 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3629 unsigned nparams = FTP->getNumArgs(); 3630 assert(FD->getNumParams() == nparams); 3631 3632 bool HasExtraParameters = (nparams > 3); 3633 3634 // Darwin passes an undocumented fourth argument of type char**. If 3635 // other platforms start sprouting these, the logic below will start 3636 // getting shifty. 3637 if (nparams == 4 && 3638 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3639 HasExtraParameters = false; 3640 3641 if (HasExtraParameters) { 3642 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3643 FD->setInvalidDecl(true); 3644 nparams = 3; 3645 } 3646 3647 // FIXME: a lot of the following diagnostics would be improved 3648 // if we had some location information about types. 3649 3650 QualType CharPP = 3651 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3652 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3653 3654 for (unsigned i = 0; i < nparams; ++i) { 3655 QualType AT = FTP->getArgType(i); 3656 3657 bool mismatch = true; 3658 3659 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3660 mismatch = false; 3661 else if (Expected[i] == CharPP) { 3662 // As an extension, the following forms are okay: 3663 // char const ** 3664 // char const * const * 3665 // char * const * 3666 3667 QualifierCollector qs; 3668 const PointerType* PT; 3669 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3670 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3671 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3672 qs.removeConst(); 3673 mismatch = !qs.empty(); 3674 } 3675 } 3676 3677 if (mismatch) { 3678 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3679 // TODO: suggest replacing given type with expected type 3680 FD->setInvalidDecl(true); 3681 } 3682 } 3683 3684 if (nparams == 1 && !FD->isInvalidDecl()) { 3685 Diag(FD->getLocation(), diag::warn_main_one_arg); 3686 } 3687} 3688 3689bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3690 // FIXME: Need strict checking. In C89, we need to check for 3691 // any assignment, increment, decrement, function-calls, or 3692 // commas outside of a sizeof. In C99, it's the same list, 3693 // except that the aforementioned are allowed in unevaluated 3694 // expressions. Everything else falls under the 3695 // "may accept other forms of constant expressions" exception. 3696 // (We never end up here for C++, so the constant expression 3697 // rules there don't matter.) 3698 if (Init->isConstantInitializer(Context)) 3699 return false; 3700 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3701 << Init->getSourceRange(); 3702 return true; 3703} 3704 3705void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3706 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3707} 3708 3709/// AddInitializerToDecl - Adds the initializer Init to the 3710/// declaration dcl. If DirectInit is true, this is C++ direct 3711/// initialization rather than copy initialization. 3712void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3713 Decl *RealDecl = dcl.getAs<Decl>(); 3714 // If there is no declaration, there was an error parsing it. Just ignore 3715 // the initializer. 3716 if (RealDecl == 0) 3717 return; 3718 3719 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3720 // With declarators parsed the way they are, the parser cannot 3721 // distinguish between a normal initializer and a pure-specifier. 3722 // Thus this grotesque test. 3723 IntegerLiteral *IL; 3724 Expr *Init = static_cast<Expr *>(init.get()); 3725 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3726 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3727 CheckPureMethod(Method, Init->getSourceRange()); 3728 else { 3729 Diag(Method->getLocation(), diag::err_member_function_initialization) 3730 << Method->getDeclName() << Init->getSourceRange(); 3731 Method->setInvalidDecl(); 3732 } 3733 return; 3734 } 3735 3736 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3737 if (!VDecl) { 3738 if (getLangOptions().CPlusPlus && 3739 RealDecl->getLexicalDeclContext()->isRecord() && 3740 isa<NamedDecl>(RealDecl)) 3741 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3742 << cast<NamedDecl>(RealDecl)->getDeclName(); 3743 else 3744 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3745 RealDecl->setInvalidDecl(); 3746 return; 3747 } 3748 3749 // A definition must end up with a complete type, which means it must be 3750 // complete with the restriction that an array type might be completed by the 3751 // initializer; note that later code assumes this restriction. 3752 QualType BaseDeclType = VDecl->getType(); 3753 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3754 BaseDeclType = Array->getElementType(); 3755 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3756 diag::err_typecheck_decl_incomplete_type)) { 3757 RealDecl->setInvalidDecl(); 3758 return; 3759 } 3760 3761 // The variable can not have an abstract class type. 3762 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3763 diag::err_abstract_type_in_decl, 3764 AbstractVariableType)) 3765 VDecl->setInvalidDecl(); 3766 3767 const VarDecl *Def; 3768 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3769 Diag(VDecl->getLocation(), diag::err_redefinition) 3770 << VDecl->getDeclName(); 3771 Diag(Def->getLocation(), diag::note_previous_definition); 3772 VDecl->setInvalidDecl(); 3773 return; 3774 } 3775 3776 // Take ownership of the expression, now that we're sure we have somewhere 3777 // to put it. 3778 Expr *Init = init.takeAs<Expr>(); 3779 assert(Init && "missing initializer"); 3780 3781 // Capture the variable that is being initialized and the style of 3782 // initialization. 3783 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3784 3785 // FIXME: Poor source location information. 3786 InitializationKind Kind 3787 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3788 Init->getLocStart(), 3789 Init->getLocEnd()) 3790 : InitializationKind::CreateCopy(VDecl->getLocation(), 3791 Init->getLocStart()); 3792 3793 // Get the decls type and save a reference for later, since 3794 // CheckInitializerTypes may change it. 3795 QualType DclT = VDecl->getType(), SavT = DclT; 3796 if (VDecl->isBlockVarDecl()) { 3797 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3798 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3799 VDecl->setInvalidDecl(); 3800 } else if (!VDecl->isInvalidDecl()) { 3801 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3802 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3803 MultiExprArg(*this, (void**)&Init, 1), 3804 &DclT); 3805 if (Result.isInvalid()) { 3806 VDecl->setInvalidDecl(); 3807 return; 3808 } 3809 3810 Init = Result.takeAs<Expr>(); 3811 3812 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3813 // Don't check invalid declarations to avoid emitting useless diagnostics. 3814 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3815 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3816 CheckForConstantInitializer(Init, DclT); 3817 } 3818 } 3819 } else if (VDecl->isStaticDataMember() && 3820 VDecl->getLexicalDeclContext()->isRecord()) { 3821 // This is an in-class initialization for a static data member, e.g., 3822 // 3823 // struct S { 3824 // static const int value = 17; 3825 // }; 3826 3827 // Attach the initializer 3828 VDecl->setInit(Init); 3829 3830 // C++ [class.mem]p4: 3831 // A member-declarator can contain a constant-initializer only 3832 // if it declares a static member (9.4) of const integral or 3833 // const enumeration type, see 9.4.2. 3834 QualType T = VDecl->getType(); 3835 if (!T->isDependentType() && 3836 (!Context.getCanonicalType(T).isConstQualified() || 3837 !T->isIntegralType())) { 3838 Diag(VDecl->getLocation(), diag::err_member_initialization) 3839 << VDecl->getDeclName() << Init->getSourceRange(); 3840 VDecl->setInvalidDecl(); 3841 } else { 3842 // C++ [class.static.data]p4: 3843 // If a static data member is of const integral or const 3844 // enumeration type, its declaration in the class definition 3845 // can specify a constant-initializer which shall be an 3846 // integral constant expression (5.19). 3847 if (!Init->isTypeDependent() && 3848 !Init->getType()->isIntegralType()) { 3849 // We have a non-dependent, non-integral or enumeration type. 3850 Diag(Init->getSourceRange().getBegin(), 3851 diag::err_in_class_initializer_non_integral_type) 3852 << Init->getType() << Init->getSourceRange(); 3853 VDecl->setInvalidDecl(); 3854 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3855 // Check whether the expression is a constant expression. 3856 llvm::APSInt Value; 3857 SourceLocation Loc; 3858 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3859 Diag(Loc, diag::err_in_class_initializer_non_constant) 3860 << Init->getSourceRange(); 3861 VDecl->setInvalidDecl(); 3862 } else if (!VDecl->getType()->isDependentType()) 3863 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3864 } 3865 } 3866 } else if (VDecl->isFileVarDecl()) { 3867 if (VDecl->getStorageClass() == VarDecl::Extern && 3868 (!getLangOptions().CPlusPlus || 3869 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 3870 Diag(VDecl->getLocation(), diag::warn_extern_init); 3871 if (!VDecl->isInvalidDecl()) { 3872 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3873 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3874 MultiExprArg(*this, (void**)&Init, 1), 3875 &DclT); 3876 if (Result.isInvalid()) { 3877 VDecl->setInvalidDecl(); 3878 return; 3879 } 3880 3881 Init = Result.takeAs<Expr>(); 3882 } 3883 3884 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3885 // Don't check invalid declarations to avoid emitting useless diagnostics. 3886 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3887 // C99 6.7.8p4. All file scoped initializers need to be constant. 3888 CheckForConstantInitializer(Init, DclT); 3889 } 3890 } 3891 // If the type changed, it means we had an incomplete type that was 3892 // completed by the initializer. For example: 3893 // int ary[] = { 1, 3, 5 }; 3894 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3895 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3896 VDecl->setType(DclT); 3897 Init->setType(DclT); 3898 } 3899 3900 Init = MaybeCreateCXXExprWithTemporaries(Init); 3901 // Attach the initializer to the decl. 3902 VDecl->setInit(Init); 3903 3904 if (getLangOptions().CPlusPlus) { 3905 // Make sure we mark the destructor as used if necessary. 3906 QualType InitType = VDecl->getType(); 3907 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3908 InitType = Context.getBaseElementType(Array); 3909 if (const RecordType *Record = InitType->getAs<RecordType>()) 3910 FinalizeVarWithDestructor(VDecl, Record); 3911 } 3912 3913 return; 3914} 3915 3916/// ActOnInitializerError - Given that there was an error parsing an 3917/// initializer for the given declaration, try to return to some form 3918/// of sanity. 3919void Sema::ActOnInitializerError(DeclPtrTy dcl) { 3920 // Our main concern here is re-establishing invariants like "a 3921 // variable's type is either dependent or complete". 3922 Decl *D = dcl.getAs<Decl>(); 3923 if (!D || D->isInvalidDecl()) return; 3924 3925 VarDecl *VD = dyn_cast<VarDecl>(D); 3926 if (!VD) return; 3927 3928 QualType Ty = VD->getType(); 3929 if (Ty->isDependentType()) return; 3930 3931 // Require a complete type. 3932 if (RequireCompleteType(VD->getLocation(), 3933 Context.getBaseElementType(Ty), 3934 diag::err_typecheck_decl_incomplete_type)) { 3935 VD->setInvalidDecl(); 3936 return; 3937 } 3938 3939 // Require an abstract type. 3940 if (RequireNonAbstractType(VD->getLocation(), Ty, 3941 diag::err_abstract_type_in_decl, 3942 AbstractVariableType)) { 3943 VD->setInvalidDecl(); 3944 return; 3945 } 3946 3947 // Don't bother complaining about constructors or destructors, 3948 // though. 3949} 3950 3951void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3952 bool TypeContainsUndeducedAuto) { 3953 Decl *RealDecl = dcl.getAs<Decl>(); 3954 3955 // If there is no declaration, there was an error parsing it. Just ignore it. 3956 if (RealDecl == 0) 3957 return; 3958 3959 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3960 QualType Type = Var->getType(); 3961 3962 // C++0x [dcl.spec.auto]p3 3963 if (TypeContainsUndeducedAuto) { 3964 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3965 << Var->getDeclName() << Type; 3966 Var->setInvalidDecl(); 3967 return; 3968 } 3969 3970 switch (Var->isThisDeclarationADefinition()) { 3971 case VarDecl::Definition: 3972 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 3973 break; 3974 3975 // We have an out-of-line definition of a static data member 3976 // that has an in-class initializer, so we type-check this like 3977 // a declaration. 3978 // 3979 // Fall through 3980 3981 case VarDecl::DeclarationOnly: 3982 // It's only a declaration. 3983 3984 // Block scope. C99 6.7p7: If an identifier for an object is 3985 // declared with no linkage (C99 6.2.2p6), the type for the 3986 // object shall be complete. 3987 if (!Type->isDependentType() && Var->isBlockVarDecl() && 3988 !Var->getLinkage() && !Var->isInvalidDecl() && 3989 RequireCompleteType(Var->getLocation(), Type, 3990 diag::err_typecheck_decl_incomplete_type)) 3991 Var->setInvalidDecl(); 3992 3993 // Make sure that the type is not abstract. 3994 if (!Type->isDependentType() && !Var->isInvalidDecl() && 3995 RequireNonAbstractType(Var->getLocation(), Type, 3996 diag::err_abstract_type_in_decl, 3997 AbstractVariableType)) 3998 Var->setInvalidDecl(); 3999 return; 4000 4001 case VarDecl::TentativeDefinition: 4002 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4003 // object that has file scope without an initializer, and without a 4004 // storage-class specifier or with the storage-class specifier "static", 4005 // constitutes a tentative definition. Note: A tentative definition with 4006 // external linkage is valid (C99 6.2.2p5). 4007 if (!Var->isInvalidDecl()) { 4008 if (const IncompleteArrayType *ArrayT 4009 = Context.getAsIncompleteArrayType(Type)) { 4010 if (RequireCompleteType(Var->getLocation(), 4011 ArrayT->getElementType(), 4012 diag::err_illegal_decl_array_incomplete_type)) 4013 Var->setInvalidDecl(); 4014 } else if (Var->getStorageClass() == VarDecl::Static) { 4015 // C99 6.9.2p3: If the declaration of an identifier for an object is 4016 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4017 // declared type shall not be an incomplete type. 4018 // NOTE: code such as the following 4019 // static struct s; 4020 // struct s { int a; }; 4021 // is accepted by gcc. Hence here we issue a warning instead of 4022 // an error and we do not invalidate the static declaration. 4023 // NOTE: to avoid multiple warnings, only check the first declaration. 4024 if (Var->getPreviousDeclaration() == 0) 4025 RequireCompleteType(Var->getLocation(), Type, 4026 diag::ext_typecheck_decl_incomplete_type); 4027 } 4028 } 4029 4030 // Record the tentative definition; we're done. 4031 if (!Var->isInvalidDecl()) 4032 TentativeDefinitions.push_back(Var); 4033 return; 4034 } 4035 4036 // Provide a specific diagnostic for uninitialized variable 4037 // definitions with incomplete array type. 4038 if (Type->isIncompleteArrayType()) { 4039 Diag(Var->getLocation(), 4040 diag::err_typecheck_incomplete_array_needs_initializer); 4041 Var->setInvalidDecl(); 4042 return; 4043 } 4044 4045 // Provide a specific diagnostic for uninitialized variable 4046 // definitions with reference type. 4047 if (Type->isReferenceType()) { 4048 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4049 << Var->getDeclName() 4050 << SourceRange(Var->getLocation(), Var->getLocation()); 4051 Var->setInvalidDecl(); 4052 return; 4053 } 4054 4055 // Do not attempt to type-check the default initializer for a 4056 // variable with dependent type. 4057 if (Type->isDependentType()) 4058 return; 4059 4060 if (Var->isInvalidDecl()) 4061 return; 4062 4063 if (RequireCompleteType(Var->getLocation(), 4064 Context.getBaseElementType(Type), 4065 diag::err_typecheck_decl_incomplete_type)) { 4066 Var->setInvalidDecl(); 4067 return; 4068 } 4069 4070 // The variable can not have an abstract class type. 4071 if (RequireNonAbstractType(Var->getLocation(), Type, 4072 diag::err_abstract_type_in_decl, 4073 AbstractVariableType)) { 4074 Var->setInvalidDecl(); 4075 return; 4076 } 4077 4078 const RecordType *Record 4079 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4080 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4081 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4082 // C++03 [dcl.init]p9: 4083 // If no initializer is specified for an object, and the 4084 // object is of (possibly cv-qualified) non-POD class type (or 4085 // array thereof), the object shall be default-initialized; if 4086 // the object is of const-qualified type, the underlying class 4087 // type shall have a user-declared default 4088 // constructor. Otherwise, if no initializer is specified for 4089 // a non- static object, the object and its subobjects, if 4090 // any, have an indeterminate initial value); if the object 4091 // or any of its subobjects are of const-qualified type, the 4092 // program is ill-formed. 4093 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4094 } else { 4095 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4096 InitializationKind Kind 4097 = InitializationKind::CreateDefault(Var->getLocation()); 4098 4099 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4100 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4101 MultiExprArg(*this, 0, 0)); 4102 if (Init.isInvalid()) 4103 Var->setInvalidDecl(); 4104 else if (Init.get()) 4105 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4106 } 4107 4108 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4109 FinalizeVarWithDestructor(Var, Record); 4110 } 4111} 4112 4113Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4114 DeclPtrTy *Group, 4115 unsigned NumDecls) { 4116 llvm::SmallVector<Decl*, 8> Decls; 4117 4118 if (DS.isTypeSpecOwned()) 4119 Decls.push_back((Decl*)DS.getTypeRep()); 4120 4121 for (unsigned i = 0; i != NumDecls; ++i) 4122 if (Decl *D = Group[i].getAs<Decl>()) 4123 Decls.push_back(D); 4124 4125 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4126 Decls.data(), Decls.size())); 4127} 4128 4129 4130/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4131/// to introduce parameters into function prototype scope. 4132Sema::DeclPtrTy 4133Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4134 const DeclSpec &DS = D.getDeclSpec(); 4135 4136 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4137 VarDecl::StorageClass StorageClass = VarDecl::None; 4138 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4139 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4140 StorageClass = VarDecl::Register; 4141 StorageClassAsWritten = VarDecl::Register; 4142 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4143 Diag(DS.getStorageClassSpecLoc(), 4144 diag::err_invalid_storage_class_in_func_decl); 4145 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4146 } 4147 4148 if (D.getDeclSpec().isThreadSpecified()) 4149 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4150 4151 DiagnoseFunctionSpecifiers(D); 4152 4153 // Check that there are no default arguments inside the type of this 4154 // parameter (C++ only). 4155 if (getLangOptions().CPlusPlus) 4156 CheckExtraCXXDefaultArguments(D); 4157 4158 TypeSourceInfo *TInfo = 0; 4159 TagDecl *OwnedDecl = 0; 4160 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4161 4162 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4163 // C++ [dcl.fct]p6: 4164 // Types shall not be defined in return or parameter types. 4165 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4166 << Context.getTypeDeclType(OwnedDecl); 4167 } 4168 4169 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4170 IdentifierInfo *II = D.getIdentifier(); 4171 if (II) { 4172 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4173 ForRedeclaration); 4174 LookupName(R, S); 4175 if (R.isSingleResult()) { 4176 NamedDecl *PrevDecl = R.getFoundDecl(); 4177 if (PrevDecl->isTemplateParameter()) { 4178 // Maybe we will complain about the shadowed template parameter. 4179 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4180 // Just pretend that we didn't see the previous declaration. 4181 PrevDecl = 0; 4182 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4183 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4184 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4185 4186 // Recover by removing the name 4187 II = 0; 4188 D.SetIdentifier(0, D.getIdentifierLoc()); 4189 D.setInvalidType(true); 4190 } 4191 } 4192 } 4193 4194 // Temporarily put parameter variables in the translation unit, not 4195 // the enclosing context. This prevents them from accidentally 4196 // looking like class members in C++. 4197 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4198 TInfo, parmDeclType, II, 4199 D.getIdentifierLoc(), 4200 StorageClass, StorageClassAsWritten); 4201 4202 if (D.isInvalidType()) 4203 New->setInvalidDecl(); 4204 4205 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4206 if (D.getCXXScopeSpec().isSet()) { 4207 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4208 << D.getCXXScopeSpec().getRange(); 4209 New->setInvalidDecl(); 4210 } 4211 4212 // Add the parameter declaration into this scope. 4213 S->AddDecl(DeclPtrTy::make(New)); 4214 if (II) 4215 IdResolver.AddDecl(New); 4216 4217 ProcessDeclAttributes(S, New, D); 4218 4219 if (New->hasAttr<BlocksAttr>()) { 4220 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4221 } 4222 return DeclPtrTy::make(New); 4223} 4224 4225ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4226 TypeSourceInfo *TSInfo, QualType T, 4227 IdentifierInfo *Name, 4228 SourceLocation NameLoc, 4229 VarDecl::StorageClass StorageClass, 4230 VarDecl::StorageClass StorageClassAsWritten) { 4231 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4232 adjustParameterType(T), TSInfo, 4233 StorageClass, StorageClassAsWritten, 4234 0); 4235 4236 // Parameters can not be abstract class types. 4237 // For record types, this is done by the AbstractClassUsageDiagnoser once 4238 // the class has been completely parsed. 4239 if (!CurContext->isRecord() && 4240 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4241 AbstractParamType)) 4242 New->setInvalidDecl(); 4243 4244 // Parameter declarators cannot be interface types. All ObjC objects are 4245 // passed by reference. 4246 if (T->isObjCInterfaceType()) { 4247 Diag(NameLoc, 4248 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4249 New->setInvalidDecl(); 4250 } 4251 4252 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4253 // duration shall not be qualified by an address-space qualifier." 4254 // Since all parameters have automatic store duration, they can not have 4255 // an address space. 4256 if (T.getAddressSpace() != 0) { 4257 Diag(NameLoc, diag::err_arg_with_address_space); 4258 New->setInvalidDecl(); 4259 } 4260 4261 return New; 4262} 4263 4264void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4265 SourceLocation LocAfterDecls) { 4266 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4267 "Not a function declarator!"); 4268 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4269 4270 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4271 // for a K&R function. 4272 if (!FTI.hasPrototype) { 4273 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4274 --i; 4275 if (FTI.ArgInfo[i].Param == 0) { 4276 llvm::SmallString<256> Code; 4277 llvm::raw_svector_ostream(Code) << " int " 4278 << FTI.ArgInfo[i].Ident->getName() 4279 << ";\n"; 4280 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4281 << FTI.ArgInfo[i].Ident 4282 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4283 4284 // Implicitly declare the argument as type 'int' for lack of a better 4285 // type. 4286 DeclSpec DS; 4287 const char* PrevSpec; // unused 4288 unsigned DiagID; // unused 4289 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4290 PrevSpec, DiagID); 4291 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4292 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4293 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4294 } 4295 } 4296 } 4297} 4298 4299Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4300 Declarator &D) { 4301 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4302 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4303 "Not a function declarator!"); 4304 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4305 4306 if (FTI.hasPrototype) { 4307 // FIXME: Diagnose arguments without names in C. 4308 } 4309 4310 Scope *ParentScope = FnBodyScope->getParent(); 4311 4312 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4313 MultiTemplateParamsArg(*this), 4314 /*IsFunctionDefinition=*/true); 4315 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4316} 4317 4318static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4319 // Don't warn about invalid declarations. 4320 if (FD->isInvalidDecl()) 4321 return false; 4322 4323 // Or declarations that aren't global. 4324 if (!FD->isGlobal()) 4325 return false; 4326 4327 // Don't warn about C++ member functions. 4328 if (isa<CXXMethodDecl>(FD)) 4329 return false; 4330 4331 // Don't warn about 'main'. 4332 if (FD->isMain()) 4333 return false; 4334 4335 // Don't warn about inline functions. 4336 if (FD->isInlineSpecified()) 4337 return false; 4338 4339 // Don't warn about function templates. 4340 if (FD->getDescribedFunctionTemplate()) 4341 return false; 4342 4343 // Don't warn about function template specializations. 4344 if (FD->isFunctionTemplateSpecialization()) 4345 return false; 4346 4347 bool MissingPrototype = true; 4348 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4349 Prev; Prev = Prev->getPreviousDeclaration()) { 4350 // Ignore any declarations that occur in function or method 4351 // scope, because they aren't visible from the header. 4352 if (Prev->getDeclContext()->isFunctionOrMethod()) 4353 continue; 4354 4355 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4356 break; 4357 } 4358 4359 return MissingPrototype; 4360} 4361 4362Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4363 // Clear the last template instantiation error context. 4364 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4365 4366 if (!D) 4367 return D; 4368 FunctionDecl *FD = 0; 4369 4370 if (FunctionTemplateDecl *FunTmpl 4371 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4372 FD = FunTmpl->getTemplatedDecl(); 4373 else 4374 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4375 4376 // Enter a new function scope 4377 PushFunctionScope(); 4378 4379 // See if this is a redefinition. 4380 // But don't complain if we're in GNU89 mode and the previous definition 4381 // was an extern inline function. 4382 const FunctionDecl *Definition; 4383 if (FD->getBody(Definition) && 4384 !canRedefineFunction(Definition, getLangOptions())) { 4385 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4386 Diag(Definition->getLocation(), diag::note_previous_definition); 4387 } 4388 4389 // Builtin functions cannot be defined. 4390 if (unsigned BuiltinID = FD->getBuiltinID()) { 4391 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4392 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4393 FD->setInvalidDecl(); 4394 } 4395 } 4396 4397 // The return type of a function definition must be complete 4398 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4399 QualType ResultType = FD->getResultType(); 4400 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4401 !FD->isInvalidDecl() && 4402 RequireCompleteType(FD->getLocation(), ResultType, 4403 diag::err_func_def_incomplete_result)) 4404 FD->setInvalidDecl(); 4405 4406 // GNU warning -Wmissing-prototypes: 4407 // Warn if a global function is defined without a previous 4408 // prototype declaration. This warning is issued even if the 4409 // definition itself provides a prototype. The aim is to detect 4410 // global functions that fail to be declared in header files. 4411 if (ShouldWarnAboutMissingPrototype(FD)) 4412 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4413 4414 if (FnBodyScope) 4415 PushDeclContext(FnBodyScope, FD); 4416 4417 // Check the validity of our function parameters 4418 CheckParmsForFunctionDef(FD); 4419 4420 bool ShouldCheckShadow = 4421 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4422 4423 // Introduce our parameters into the function scope 4424 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4425 ParmVarDecl *Param = FD->getParamDecl(p); 4426 Param->setOwningFunction(FD); 4427 4428 // If this has an identifier, add it to the scope stack. 4429 if (Param->getIdentifier() && FnBodyScope) { 4430 if (ShouldCheckShadow) 4431 CheckShadow(FnBodyScope, Param); 4432 4433 PushOnScopeChains(Param, FnBodyScope); 4434 } 4435 } 4436 4437 // Checking attributes of current function definition 4438 // dllimport attribute. 4439 if (FD->getAttr<DLLImportAttr>() && 4440 (!FD->getAttr<DLLExportAttr>())) { 4441 // dllimport attribute cannot be applied to definition. 4442 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4443 Diag(FD->getLocation(), 4444 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4445 << "dllimport"; 4446 FD->setInvalidDecl(); 4447 return DeclPtrTy::make(FD); 4448 } 4449 4450 // Visual C++ appears to not think this is an issue, so only issue 4451 // a warning when Microsoft extensions are disabled. 4452 if (!LangOpts.Microsoft) { 4453 // If a symbol previously declared dllimport is later defined, the 4454 // attribute is ignored in subsequent references, and a warning is 4455 // emitted. 4456 Diag(FD->getLocation(), 4457 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4458 << FD->getNameAsCString() << "dllimport"; 4459 } 4460 } 4461 return DeclPtrTy::make(FD); 4462} 4463 4464Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4465 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4466} 4467 4468Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4469 bool IsInstantiation) { 4470 Decl *dcl = D.getAs<Decl>(); 4471 Stmt *Body = BodyArg.takeAs<Stmt>(); 4472 4473 FunctionDecl *FD = 0; 4474 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4475 if (FunTmpl) 4476 FD = FunTmpl->getTemplatedDecl(); 4477 else 4478 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4479 4480 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4481 4482 if (FD) { 4483 FD->setBody(Body); 4484 if (FD->isMain()) { 4485 // C and C++ allow for main to automagically return 0. 4486 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4487 FD->setHasImplicitReturnZero(true); 4488 WP.disableCheckFallThrough(); 4489 } 4490 4491 if (!FD->isInvalidDecl()) 4492 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4493 4494 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4495 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4496 4497 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4498 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4499 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4500 MD->setBody(Body); 4501 MD->setEndLoc(Body->getLocEnd()); 4502 if (!MD->isInvalidDecl()) 4503 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4504 } else { 4505 Body->Destroy(Context); 4506 return DeclPtrTy(); 4507 } 4508 4509 // Verify and clean out per-function state. 4510 4511 // Check goto/label use. 4512 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4513 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4514 LabelStmt *L = I->second; 4515 4516 // Verify that we have no forward references left. If so, there was a goto 4517 // or address of a label taken, but no definition of it. Label fwd 4518 // definitions are indicated with a null substmt. 4519 if (L->getSubStmt() != 0) 4520 continue; 4521 4522 // Emit error. 4523 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4524 4525 // At this point, we have gotos that use the bogus label. Stitch it into 4526 // the function body so that they aren't leaked and that the AST is well 4527 // formed. 4528 if (Body == 0) { 4529 // The whole function wasn't parsed correctly, just delete this. 4530 L->Destroy(Context); 4531 continue; 4532 } 4533 4534 // Otherwise, the body is valid: we want to stitch the label decl into the 4535 // function somewhere so that it is properly owned and so that the goto 4536 // has a valid target. Do this by creating a new compound stmt with the 4537 // label in it. 4538 4539 // Give the label a sub-statement. 4540 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4541 4542 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4543 cast<CXXTryStmt>(Body)->getTryBlock() : 4544 cast<CompoundStmt>(Body); 4545 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4546 Compound->body_end()); 4547 Elements.push_back(L); 4548 Compound->setStmts(Context, Elements.data(), Elements.size()); 4549 } 4550 4551 if (Body) { 4552 // C++ constructors that have function-try-blocks can't have return 4553 // statements in the handlers of that block. (C++ [except.handle]p14) 4554 // Verify this. 4555 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4556 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4557 4558 // Verify that that gotos and switch cases don't jump into scopes illegally. 4559 // Verify that that gotos and switch cases don't jump into scopes illegally. 4560 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 4561 DiagnoseInvalidJumps(Body); 4562 4563 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4564 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4565 Destructor->getParent()); 4566 4567 // If any errors have occurred, clear out any temporaries that may have 4568 // been leftover. This ensures that these temporaries won't be picked up for 4569 // deletion in some later function. 4570 if (PP.getDiagnostics().hasErrorOccurred()) 4571 ExprTemporaries.clear(); 4572 else if (!isa<FunctionTemplateDecl>(dcl)) { 4573 // Since the body is valid, issue any analysis-based warnings that are 4574 // enabled. 4575 QualType ResultType; 4576 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4577 ResultType = FD->getResultType(); 4578 } 4579 else { 4580 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4581 ResultType = MD->getResultType(); 4582 } 4583 AnalysisWarnings.IssueWarnings(WP, dcl); 4584 } 4585 4586 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4587 } 4588 4589 if (!IsInstantiation) 4590 PopDeclContext(); 4591 4592 PopFunctionOrBlockScope(); 4593 4594 // If any errors have occurred, clear out any temporaries that may have 4595 // been leftover. This ensures that these temporaries won't be picked up for 4596 // deletion in some later function. 4597 if (getDiagnostics().hasErrorOccurred()) 4598 ExprTemporaries.clear(); 4599 4600 return D; 4601} 4602 4603/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4604/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4605NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4606 IdentifierInfo &II, Scope *S) { 4607 // Before we produce a declaration for an implicitly defined 4608 // function, see whether there was a locally-scoped declaration of 4609 // this name as a function or variable. If so, use that 4610 // (non-visible) declaration, and complain about it. 4611 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4612 = LocallyScopedExternalDecls.find(&II); 4613 if (Pos != LocallyScopedExternalDecls.end()) { 4614 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4615 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4616 return Pos->second; 4617 } 4618 4619 // Extension in C99. Legal in C90, but warn about it. 4620 if (II.getName().startswith("__builtin_")) 4621 Diag(Loc, diag::warn_builtin_unknown) << &II; 4622 else if (getLangOptions().C99) 4623 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4624 else 4625 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4626 4627 // Set a Declarator for the implicit definition: int foo(); 4628 const char *Dummy; 4629 DeclSpec DS; 4630 unsigned DiagID; 4631 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4632 Error = Error; // Silence warning. 4633 assert(!Error && "Error setting up implicit decl!"); 4634 Declarator D(DS, Declarator::BlockContext); 4635 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4636 0, 0, false, SourceLocation(), 4637 false, 0,0,0, Loc, Loc, D), 4638 SourceLocation()); 4639 D.SetIdentifier(&II, Loc); 4640 4641 // Insert this function into translation-unit scope. 4642 4643 DeclContext *PrevDC = CurContext; 4644 CurContext = Context.getTranslationUnitDecl(); 4645 4646 FunctionDecl *FD = 4647 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4648 FD->setImplicit(); 4649 4650 CurContext = PrevDC; 4651 4652 AddKnownFunctionAttributes(FD); 4653 4654 return FD; 4655} 4656 4657/// \brief Adds any function attributes that we know a priori based on 4658/// the declaration of this function. 4659/// 4660/// These attributes can apply both to implicitly-declared builtins 4661/// (like __builtin___printf_chk) or to library-declared functions 4662/// like NSLog or printf. 4663void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4664 if (FD->isInvalidDecl()) 4665 return; 4666 4667 // If this is a built-in function, map its builtin attributes to 4668 // actual attributes. 4669 if (unsigned BuiltinID = FD->getBuiltinID()) { 4670 // Handle printf-formatting attributes. 4671 unsigned FormatIdx; 4672 bool HasVAListArg; 4673 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4674 if (!FD->getAttr<FormatAttr>()) 4675 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4676 HasVAListArg ? 0 : FormatIdx+2)); 4677 } 4678 4679 // Mark const if we don't care about errno and that is the only 4680 // thing preventing the function from being const. This allows 4681 // IRgen to use LLVM intrinsics for such functions. 4682 if (!getLangOptions().MathErrno && 4683 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4684 if (!FD->getAttr<ConstAttr>()) 4685 FD->addAttr(::new (Context) ConstAttr()); 4686 } 4687 4688 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4689 FD->setType(Context.getNoReturnType(FD->getType())); 4690 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4691 FD->addAttr(::new (Context) NoThrowAttr()); 4692 if (Context.BuiltinInfo.isConst(BuiltinID)) 4693 FD->addAttr(::new (Context) ConstAttr()); 4694 } 4695 4696 IdentifierInfo *Name = FD->getIdentifier(); 4697 if (!Name) 4698 return; 4699 if ((!getLangOptions().CPlusPlus && 4700 FD->getDeclContext()->isTranslationUnit()) || 4701 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4702 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4703 LinkageSpecDecl::lang_c)) { 4704 // Okay: this could be a libc/libm/Objective-C function we know 4705 // about. 4706 } else 4707 return; 4708 4709 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4710 // FIXME: NSLog and NSLogv should be target specific 4711 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4712 // FIXME: We known better than our headers. 4713 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4714 } else 4715 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4716 Name->isStr("NSLogv") ? 0 : 2)); 4717 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4718 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4719 // target-specific builtins, perhaps? 4720 if (!FD->getAttr<FormatAttr>()) 4721 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4722 Name->isStr("vasprintf") ? 0 : 3)); 4723 } 4724} 4725 4726TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4727 TypeSourceInfo *TInfo) { 4728 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4729 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4730 4731 if (!TInfo) { 4732 assert(D.isInvalidType() && "no declarator info for valid type"); 4733 TInfo = Context.getTrivialTypeSourceInfo(T); 4734 } 4735 4736 // Scope manipulation handled by caller. 4737 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4738 D.getIdentifierLoc(), 4739 D.getIdentifier(), 4740 TInfo); 4741 4742 if (const TagType *TT = T->getAs<TagType>()) { 4743 TagDecl *TD = TT->getDecl(); 4744 4745 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4746 // keep track of the TypedefDecl. 4747 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4748 TD->setTypedefForAnonDecl(NewTD); 4749 } 4750 4751 if (D.isInvalidType()) 4752 NewTD->setInvalidDecl(); 4753 return NewTD; 4754} 4755 4756 4757/// \brief Determine whether a tag with a given kind is acceptable 4758/// as a redeclaration of the given tag declaration. 4759/// 4760/// \returns true if the new tag kind is acceptable, false otherwise. 4761bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4762 TagDecl::TagKind NewTag, 4763 SourceLocation NewTagLoc, 4764 const IdentifierInfo &Name) { 4765 // C++ [dcl.type.elab]p3: 4766 // The class-key or enum keyword present in the 4767 // elaborated-type-specifier shall agree in kind with the 4768 // declaration to which the name in theelaborated-type-specifier 4769 // refers. This rule also applies to the form of 4770 // elaborated-type-specifier that declares a class-name or 4771 // friend class since it can be construed as referring to the 4772 // definition of the class. Thus, in any 4773 // elaborated-type-specifier, the enum keyword shall be used to 4774 // refer to an enumeration (7.2), the union class-keyshall be 4775 // used to refer to a union (clause 9), and either the class or 4776 // struct class-key shall be used to refer to a class (clause 9) 4777 // declared using the class or struct class-key. 4778 TagDecl::TagKind OldTag = Previous->getTagKind(); 4779 if (OldTag == NewTag) 4780 return true; 4781 4782 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4783 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4784 // Warn about the struct/class tag mismatch. 4785 bool isTemplate = false; 4786 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4787 isTemplate = Record->getDescribedClassTemplate(); 4788 4789 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4790 << (NewTag == TagDecl::TK_class) 4791 << isTemplate << &Name 4792 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 4793 OldTag == TagDecl::TK_class? "class" : "struct"); 4794 Diag(Previous->getLocation(), diag::note_previous_use); 4795 return true; 4796 } 4797 return false; 4798} 4799 4800/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4801/// former case, Name will be non-null. In the later case, Name will be null. 4802/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4803/// reference/declaration/definition of a tag. 4804Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4805 SourceLocation KWLoc, CXXScopeSpec &SS, 4806 IdentifierInfo *Name, SourceLocation NameLoc, 4807 AttributeList *Attr, AccessSpecifier AS, 4808 MultiTemplateParamsArg TemplateParameterLists, 4809 bool &OwnedDecl, bool &IsDependent) { 4810 // If this is not a definition, it must have a name. 4811 assert((Name != 0 || TUK == TUK_Definition) && 4812 "Nameless record must be a definition!"); 4813 4814 OwnedDecl = false; 4815 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4816 4817 // FIXME: Check explicit specializations more carefully. 4818 bool isExplicitSpecialization = false; 4819 if (TUK != TUK_Reference) { 4820 if (TemplateParameterList *TemplateParams 4821 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4822 (TemplateParameterList**)TemplateParameterLists.get(), 4823 TemplateParameterLists.size(), 4824 TUK == TUK_Friend, 4825 isExplicitSpecialization)) { 4826 if (TemplateParams->size() > 0) { 4827 // This is a declaration or definition of a class template (which may 4828 // be a member of another template). 4829 OwnedDecl = false; 4830 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4831 SS, Name, NameLoc, Attr, 4832 TemplateParams, 4833 AS); 4834 TemplateParameterLists.release(); 4835 return Result.get(); 4836 } else { 4837 // The "template<>" header is extraneous. 4838 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4839 << ElaboratedType::getNameForTagKind(Kind) << Name; 4840 isExplicitSpecialization = true; 4841 } 4842 } 4843 4844 TemplateParameterLists.release(); 4845 } 4846 4847 DeclContext *SearchDC = CurContext; 4848 DeclContext *DC = CurContext; 4849 bool isStdBadAlloc = false; 4850 bool Invalid = false; 4851 4852 RedeclarationKind Redecl = ForRedeclaration; 4853 if (TUK == TUK_Friend || TUK == TUK_Reference) 4854 Redecl = NotForRedeclaration; 4855 4856 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4857 4858 if (Name && SS.isNotEmpty()) { 4859 // We have a nested-name tag ('struct foo::bar'). 4860 4861 // Check for invalid 'foo::'. 4862 if (SS.isInvalid()) { 4863 Name = 0; 4864 goto CreateNewDecl; 4865 } 4866 4867 // If this is a friend or a reference to a class in a dependent 4868 // context, don't try to make a decl for it. 4869 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4870 DC = computeDeclContext(SS, false); 4871 if (!DC) { 4872 IsDependent = true; 4873 return DeclPtrTy(); 4874 } 4875 } 4876 4877 if (RequireCompleteDeclContext(SS)) 4878 return DeclPtrTy::make((Decl *)0); 4879 4880 DC = computeDeclContext(SS, true); 4881 SearchDC = DC; 4882 // Look-up name inside 'foo::'. 4883 LookupQualifiedName(Previous, DC); 4884 4885 if (Previous.isAmbiguous()) 4886 return DeclPtrTy(); 4887 4888 if (Previous.empty()) { 4889 // Name lookup did not find anything. However, if the 4890 // nested-name-specifier refers to the current instantiation, 4891 // and that current instantiation has any dependent base 4892 // classes, we might find something at instantiation time: treat 4893 // this as a dependent elaborated-type-specifier. 4894 if (Previous.wasNotFoundInCurrentInstantiation()) { 4895 IsDependent = true; 4896 return DeclPtrTy(); 4897 } 4898 4899 // A tag 'foo::bar' must already exist. 4900 Diag(NameLoc, diag::err_not_tag_in_scope) 4901 << Kind << Name << DC << SS.getRange(); 4902 Name = 0; 4903 Invalid = true; 4904 goto CreateNewDecl; 4905 } 4906 } else if (Name) { 4907 // If this is a named struct, check to see if there was a previous forward 4908 // declaration or definition. 4909 // FIXME: We're looking into outer scopes here, even when we 4910 // shouldn't be. Doing so can result in ambiguities that we 4911 // shouldn't be diagnosing. 4912 LookupName(Previous, S); 4913 4914 // Note: there used to be some attempt at recovery here. 4915 if (Previous.isAmbiguous()) 4916 return DeclPtrTy(); 4917 4918 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4919 // FIXME: This makes sure that we ignore the contexts associated 4920 // with C structs, unions, and enums when looking for a matching 4921 // tag declaration or definition. See the similar lookup tweak 4922 // in Sema::LookupName; is there a better way to deal with this? 4923 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4924 SearchDC = SearchDC->getParent(); 4925 } 4926 } 4927 4928 if (Previous.isSingleResult() && 4929 Previous.getFoundDecl()->isTemplateParameter()) { 4930 // Maybe we will complain about the shadowed template parameter. 4931 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4932 // Just pretend that we didn't see the previous declaration. 4933 Previous.clear(); 4934 } 4935 4936 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4937 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4938 // This is a declaration of or a reference to "std::bad_alloc". 4939 isStdBadAlloc = true; 4940 4941 if (Previous.empty() && StdBadAlloc) { 4942 // std::bad_alloc has been implicitly declared (but made invisible to 4943 // name lookup). Fill in this implicit declaration as the previous 4944 // declaration, so that the declarations get chained appropriately. 4945 Previous.addDecl(StdBadAlloc); 4946 } 4947 } 4948 4949 // If we didn't find a previous declaration, and this is a reference 4950 // (or friend reference), move to the correct scope. In C++, we 4951 // also need to do a redeclaration lookup there, just in case 4952 // there's a shadow friend decl. 4953 if (Name && Previous.empty() && 4954 (TUK == TUK_Reference || TUK == TUK_Friend)) { 4955 if (Invalid) goto CreateNewDecl; 4956 assert(SS.isEmpty()); 4957 4958 if (TUK == TUK_Reference) { 4959 // C++ [basic.scope.pdecl]p5: 4960 // -- for an elaborated-type-specifier of the form 4961 // 4962 // class-key identifier 4963 // 4964 // if the elaborated-type-specifier is used in the 4965 // decl-specifier-seq or parameter-declaration-clause of a 4966 // function defined in namespace scope, the identifier is 4967 // declared as a class-name in the namespace that contains 4968 // the declaration; otherwise, except as a friend 4969 // declaration, the identifier is declared in the smallest 4970 // non-class, non-function-prototype scope that contains the 4971 // declaration. 4972 // 4973 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4974 // C structs and unions. 4975 // 4976 // It is an error in C++ to declare (rather than define) an enum 4977 // type, including via an elaborated type specifier. We'll 4978 // diagnose that later; for now, declare the enum in the same 4979 // scope as we would have picked for any other tag type. 4980 // 4981 // GNU C also supports this behavior as part of its incomplete 4982 // enum types extension, while GNU C++ does not. 4983 // 4984 // Find the context where we'll be declaring the tag. 4985 // FIXME: We would like to maintain the current DeclContext as the 4986 // lexical context, 4987 while (SearchDC->isRecord()) 4988 SearchDC = SearchDC->getParent(); 4989 4990 // Find the scope where we'll be declaring the tag. 4991 while (S->isClassScope() || 4992 (getLangOptions().CPlusPlus && 4993 S->isFunctionPrototypeScope()) || 4994 ((S->getFlags() & Scope::DeclScope) == 0) || 4995 (S->getEntity() && 4996 ((DeclContext *)S->getEntity())->isTransparentContext())) 4997 S = S->getParent(); 4998 } else { 4999 assert(TUK == TUK_Friend); 5000 // C++ [namespace.memdef]p3: 5001 // If a friend declaration in a non-local class first declares a 5002 // class or function, the friend class or function is a member of 5003 // the innermost enclosing namespace. 5004 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5005 } 5006 5007 // In C++, we need to do a redeclaration lookup to properly 5008 // diagnose some problems. 5009 if (getLangOptions().CPlusPlus) { 5010 Previous.setRedeclarationKind(ForRedeclaration); 5011 LookupQualifiedName(Previous, SearchDC); 5012 } 5013 } 5014 5015 if (!Previous.empty()) { 5016 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5017 5018 // It's okay to have a tag decl in the same scope as a typedef 5019 // which hides a tag decl in the same scope. Finding this 5020 // insanity with a redeclaration lookup can only actually happen 5021 // in C++. 5022 // 5023 // This is also okay for elaborated-type-specifiers, which is 5024 // technically forbidden by the current standard but which is 5025 // okay according to the likely resolution of an open issue; 5026 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5027 if (getLangOptions().CPlusPlus) { 5028 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5029 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5030 TagDecl *Tag = TT->getDecl(); 5031 if (Tag->getDeclName() == Name && 5032 Tag->getDeclContext()->getLookupContext() 5033 ->Equals(TD->getDeclContext()->getLookupContext())) { 5034 PrevDecl = Tag; 5035 Previous.clear(); 5036 Previous.addDecl(Tag); 5037 } 5038 } 5039 } 5040 } 5041 5042 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5043 // If this is a use of a previous tag, or if the tag is already declared 5044 // in the same scope (so that the definition/declaration completes or 5045 // rementions the tag), reuse the decl. 5046 if (TUK == TUK_Reference || TUK == TUK_Friend || 5047 isDeclInScope(PrevDecl, SearchDC, S)) { 5048 // Make sure that this wasn't declared as an enum and now used as a 5049 // struct or something similar. 5050 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5051 bool SafeToContinue 5052 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 5053 Kind != TagDecl::TK_enum); 5054 if (SafeToContinue) 5055 Diag(KWLoc, diag::err_use_with_wrong_tag) 5056 << Name 5057 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5058 PrevTagDecl->getKindName()); 5059 else 5060 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5061 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5062 5063 if (SafeToContinue) 5064 Kind = PrevTagDecl->getTagKind(); 5065 else { 5066 // Recover by making this an anonymous redefinition. 5067 Name = 0; 5068 Previous.clear(); 5069 Invalid = true; 5070 } 5071 } 5072 5073 if (!Invalid) { 5074 // If this is a use, just return the declaration we found. 5075 5076 // FIXME: In the future, return a variant or some other clue 5077 // for the consumer of this Decl to know it doesn't own it. 5078 // For our current ASTs this shouldn't be a problem, but will 5079 // need to be changed with DeclGroups. 5080 if (TUK == TUK_Reference || TUK == TUK_Friend) 5081 return DeclPtrTy::make(PrevTagDecl); 5082 5083 // Diagnose attempts to redefine a tag. 5084 if (TUK == TUK_Definition) { 5085 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5086 // If we're defining a specialization and the previous definition 5087 // is from an implicit instantiation, don't emit an error 5088 // here; we'll catch this in the general case below. 5089 if (!isExplicitSpecialization || 5090 !isa<CXXRecordDecl>(Def) || 5091 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5092 == TSK_ExplicitSpecialization) { 5093 Diag(NameLoc, diag::err_redefinition) << Name; 5094 Diag(Def->getLocation(), diag::note_previous_definition); 5095 // If this is a redefinition, recover by making this 5096 // struct be anonymous, which will make any later 5097 // references get the previous definition. 5098 Name = 0; 5099 Previous.clear(); 5100 Invalid = true; 5101 } 5102 } else { 5103 // If the type is currently being defined, complain 5104 // about a nested redefinition. 5105 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5106 if (Tag->isBeingDefined()) { 5107 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5108 Diag(PrevTagDecl->getLocation(), 5109 diag::note_previous_definition); 5110 Name = 0; 5111 Previous.clear(); 5112 Invalid = true; 5113 } 5114 } 5115 5116 // Okay, this is definition of a previously declared or referenced 5117 // tag PrevDecl. We're going to create a new Decl for it. 5118 } 5119 } 5120 // If we get here we have (another) forward declaration or we 5121 // have a definition. Just create a new decl. 5122 5123 } else { 5124 // If we get here, this is a definition of a new tag type in a nested 5125 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5126 // new decl/type. We set PrevDecl to NULL so that the entities 5127 // have distinct types. 5128 Previous.clear(); 5129 } 5130 // If we get here, we're going to create a new Decl. If PrevDecl 5131 // is non-NULL, it's a definition of the tag declared by 5132 // PrevDecl. If it's NULL, we have a new definition. 5133 5134 5135 // Otherwise, PrevDecl is not a tag, but was found with tag 5136 // lookup. This is only actually possible in C++, where a few 5137 // things like templates still live in the tag namespace. 5138 } else { 5139 assert(getLangOptions().CPlusPlus); 5140 5141 // Use a better diagnostic if an elaborated-type-specifier 5142 // found the wrong kind of type on the first 5143 // (non-redeclaration) lookup. 5144 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5145 !Previous.isForRedeclaration()) { 5146 unsigned Kind = 0; 5147 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5148 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5149 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5150 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5151 Invalid = true; 5152 5153 // Otherwise, only diagnose if the declaration is in scope. 5154 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5155 // do nothing 5156 5157 // Diagnose implicit declarations introduced by elaborated types. 5158 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5159 unsigned Kind = 0; 5160 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5161 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5162 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5163 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5164 Invalid = true; 5165 5166 // Otherwise it's a declaration. Call out a particularly common 5167 // case here. 5168 } else if (isa<TypedefDecl>(PrevDecl)) { 5169 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5170 << Name 5171 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5172 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5173 Invalid = true; 5174 5175 // Otherwise, diagnose. 5176 } else { 5177 // The tag name clashes with something else in the target scope, 5178 // issue an error and recover by making this tag be anonymous. 5179 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5180 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5181 Name = 0; 5182 Invalid = true; 5183 } 5184 5185 // The existing declaration isn't relevant to us; we're in a 5186 // new scope, so clear out the previous declaration. 5187 Previous.clear(); 5188 } 5189 } 5190 5191CreateNewDecl: 5192 5193 TagDecl *PrevDecl = 0; 5194 if (Previous.isSingleResult()) 5195 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5196 5197 // If there is an identifier, use the location of the identifier as the 5198 // location of the decl, otherwise use the location of the struct/union 5199 // keyword. 5200 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5201 5202 // Otherwise, create a new declaration. If there is a previous 5203 // declaration of the same entity, the two will be linked via 5204 // PrevDecl. 5205 TagDecl *New; 5206 5207 if (Kind == TagDecl::TK_enum) { 5208 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5209 // enum X { A, B, C } D; D should chain to X. 5210 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5211 cast_or_null<EnumDecl>(PrevDecl)); 5212 // If this is an undefined enum, warn. 5213 if (TUK != TUK_Definition && !Invalid) { 5214 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5215 : diag::ext_forward_ref_enum; 5216 Diag(Loc, DK); 5217 } 5218 } else { 5219 // struct/union/class 5220 5221 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5222 // struct X { int A; } D; D should chain to X. 5223 if (getLangOptions().CPlusPlus) { 5224 // FIXME: Look for a way to use RecordDecl for simple structs. 5225 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5226 cast_or_null<CXXRecordDecl>(PrevDecl)); 5227 5228 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5229 StdBadAlloc = cast<CXXRecordDecl>(New); 5230 } else 5231 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5232 cast_or_null<RecordDecl>(PrevDecl)); 5233 } 5234 5235 // Maybe add qualifier info. 5236 if (SS.isNotEmpty()) { 5237 NestedNameSpecifier *NNS 5238 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5239 New->setQualifierInfo(NNS, SS.getRange()); 5240 } 5241 5242 if (Kind != TagDecl::TK_enum) { 5243 // Handle #pragma pack: if the #pragma pack stack has non-default 5244 // alignment, make up a packed attribute for this decl. These 5245 // attributes are checked when the ASTContext lays out the 5246 // structure. 5247 // 5248 // It is important for implementing the correct semantics that this 5249 // happen here (in act on tag decl). The #pragma pack stack is 5250 // maintained as a result of parser callbacks which can occur at 5251 // many points during the parsing of a struct declaration (because 5252 // the #pragma tokens are effectively skipped over during the 5253 // parsing of the struct). 5254 if (unsigned Alignment = getPragmaPackAlignment()) 5255 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5256 } 5257 5258 // If this is a specialization of a member class (of a class template), 5259 // check the specialization. 5260 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5261 Invalid = true; 5262 5263 if (Invalid) 5264 New->setInvalidDecl(); 5265 5266 if (Attr) 5267 ProcessDeclAttributeList(S, New, Attr); 5268 5269 // If we're declaring or defining a tag in function prototype scope 5270 // in C, note that this type can only be used within the function. 5271 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5272 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5273 5274 // Set the lexical context. If the tag has a C++ scope specifier, the 5275 // lexical context will be different from the semantic context. 5276 New->setLexicalDeclContext(CurContext); 5277 5278 // Mark this as a friend decl if applicable. 5279 if (TUK == TUK_Friend) 5280 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5281 5282 // Set the access specifier. 5283 if (!Invalid && SearchDC->isRecord()) 5284 SetMemberAccessSpecifier(New, PrevDecl, AS); 5285 5286 if (TUK == TUK_Definition) 5287 New->startDefinition(); 5288 5289 // If this has an identifier, add it to the scope stack. 5290 if (TUK == TUK_Friend) { 5291 // We might be replacing an existing declaration in the lookup tables; 5292 // if so, borrow its access specifier. 5293 if (PrevDecl) 5294 New->setAccess(PrevDecl->getAccess()); 5295 5296 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5297 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5298 if (Name) // can be null along some error paths 5299 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5300 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5301 } else if (Name) { 5302 S = getNonFieldDeclScope(S); 5303 PushOnScopeChains(New, S); 5304 } else { 5305 CurContext->addDecl(New); 5306 } 5307 5308 // If this is the C FILE type, notify the AST context. 5309 if (IdentifierInfo *II = New->getIdentifier()) 5310 if (!New->isInvalidDecl() && 5311 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5312 II->isStr("FILE")) 5313 Context.setFILEDecl(New); 5314 5315 OwnedDecl = true; 5316 return DeclPtrTy::make(New); 5317} 5318 5319void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5320 AdjustDeclIfTemplate(TagD); 5321 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5322 5323 // Enter the tag context. 5324 PushDeclContext(S, Tag); 5325} 5326 5327void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5328 SourceLocation LBraceLoc) { 5329 AdjustDeclIfTemplate(TagD); 5330 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5331 5332 FieldCollector->StartClass(); 5333 5334 if (!Record->getIdentifier()) 5335 return; 5336 5337 // C++ [class]p2: 5338 // [...] The class-name is also inserted into the scope of the 5339 // class itself; this is known as the injected-class-name. For 5340 // purposes of access checking, the injected-class-name is treated 5341 // as if it were a public member name. 5342 CXXRecordDecl *InjectedClassName 5343 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5344 CurContext, Record->getLocation(), 5345 Record->getIdentifier(), 5346 Record->getTagKeywordLoc(), 5347 Record); 5348 InjectedClassName->setImplicit(); 5349 InjectedClassName->setAccess(AS_public); 5350 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5351 InjectedClassName->setDescribedClassTemplate(Template); 5352 PushOnScopeChains(InjectedClassName, S); 5353 assert(InjectedClassName->isInjectedClassName() && 5354 "Broken injected-class-name"); 5355} 5356 5357// Traverses the class and any nested classes, making a note of any 5358// dynamic classes that have no key function so that we can mark all of 5359// their virtual member functions as "used" at the end of the translation 5360// unit. This ensures that all functions needed by the vtable will get 5361// instantiated/synthesized. 5362static void 5363RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5364 SourceLocation Loc) { 5365 // We don't look at dependent or undefined classes. 5366 if (Record->isDependentContext() || !Record->isDefinition()) 5367 return; 5368 5369 if (Record->isDynamicClass()) { 5370 const CXXMethodDecl *KeyFunction = S.Context.getKeyFunction(Record); 5371 5372 if (!KeyFunction) 5373 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, 5374 Loc)); 5375 5376 if ((!KeyFunction || (KeyFunction->getBody() && KeyFunction->isInlined())) 5377 && Record->getLinkage() == ExternalLinkage) 5378 S.Diag(Record->getLocation(), diag::warn_weak_vtable) << Record; 5379 } 5380 for (DeclContext::decl_iterator D = Record->decls_begin(), 5381 DEnd = Record->decls_end(); 5382 D != DEnd; ++D) { 5383 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5384 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5385 } 5386} 5387 5388void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5389 SourceLocation RBraceLoc) { 5390 AdjustDeclIfTemplate(TagD); 5391 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5392 Tag->setRBraceLoc(RBraceLoc); 5393 5394 if (isa<CXXRecordDecl>(Tag)) 5395 FieldCollector->FinishClass(); 5396 5397 // Exit this scope of this tag's definition. 5398 PopDeclContext(); 5399 5400 if (isa<CXXRecordDecl>(Tag) && !Tag->getLexicalDeclContext()->isRecord()) 5401 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5402 RBraceLoc); 5403 5404 // Notify the consumer that we've defined a tag. 5405 Consumer.HandleTagDeclDefinition(Tag); 5406} 5407 5408void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5409 AdjustDeclIfTemplate(TagD); 5410 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5411 Tag->setInvalidDecl(); 5412 5413 // We're undoing ActOnTagStartDefinition here, not 5414 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5415 // the FieldCollector. 5416 5417 PopDeclContext(); 5418} 5419 5420// Note that FieldName may be null for anonymous bitfields. 5421bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5422 QualType FieldTy, const Expr *BitWidth, 5423 bool *ZeroWidth) { 5424 // Default to true; that shouldn't confuse checks for emptiness 5425 if (ZeroWidth) 5426 *ZeroWidth = true; 5427 5428 // C99 6.7.2.1p4 - verify the field type. 5429 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5430 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5431 // Handle incomplete types with specific error. 5432 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5433 return true; 5434 if (FieldName) 5435 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5436 << FieldName << FieldTy << BitWidth->getSourceRange(); 5437 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5438 << FieldTy << BitWidth->getSourceRange(); 5439 } 5440 5441 // If the bit-width is type- or value-dependent, don't try to check 5442 // it now. 5443 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5444 return false; 5445 5446 llvm::APSInt Value; 5447 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5448 return true; 5449 5450 if (Value != 0 && ZeroWidth) 5451 *ZeroWidth = false; 5452 5453 // Zero-width bitfield is ok for anonymous field. 5454 if (Value == 0 && FieldName) 5455 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5456 5457 if (Value.isSigned() && Value.isNegative()) { 5458 if (FieldName) 5459 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5460 << FieldName << Value.toString(10); 5461 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5462 << Value.toString(10); 5463 } 5464 5465 if (!FieldTy->isDependentType()) { 5466 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5467 if (Value.getZExtValue() > TypeSize) { 5468 if (!getLangOptions().CPlusPlus) { 5469 if (FieldName) 5470 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5471 << FieldName << (unsigned)Value.getZExtValue() 5472 << (unsigned)TypeSize; 5473 5474 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5475 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5476 } 5477 5478 if (FieldName) 5479 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5480 << FieldName << (unsigned)Value.getZExtValue() 5481 << (unsigned)TypeSize; 5482 else 5483 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5484 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5485 } 5486 } 5487 5488 return false; 5489} 5490 5491/// ActOnField - Each field of a struct/union/class is passed into this in order 5492/// to create a FieldDecl object for it. 5493Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5494 SourceLocation DeclStart, 5495 Declarator &D, ExprTy *BitfieldWidth) { 5496 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5497 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5498 AS_public); 5499 return DeclPtrTy::make(Res); 5500} 5501 5502/// HandleField - Analyze a field of a C struct or a C++ data member. 5503/// 5504FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5505 SourceLocation DeclStart, 5506 Declarator &D, Expr *BitWidth, 5507 AccessSpecifier AS) { 5508 IdentifierInfo *II = D.getIdentifier(); 5509 SourceLocation Loc = DeclStart; 5510 if (II) Loc = D.getIdentifierLoc(); 5511 5512 TypeSourceInfo *TInfo = 0; 5513 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5514 if (getLangOptions().CPlusPlus) 5515 CheckExtraCXXDefaultArguments(D); 5516 5517 DiagnoseFunctionSpecifiers(D); 5518 5519 if (D.getDeclSpec().isThreadSpecified()) 5520 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5521 5522 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5523 ForRedeclaration); 5524 5525 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5526 // Maybe we will complain about the shadowed template parameter. 5527 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5528 // Just pretend that we didn't see the previous declaration. 5529 PrevDecl = 0; 5530 } 5531 5532 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5533 PrevDecl = 0; 5534 5535 bool Mutable 5536 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5537 SourceLocation TSSL = D.getSourceRange().getBegin(); 5538 FieldDecl *NewFD 5539 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5540 AS, PrevDecl, &D); 5541 5542 if (NewFD->isInvalidDecl()) 5543 Record->setInvalidDecl(); 5544 5545 if (NewFD->isInvalidDecl() && PrevDecl) { 5546 // Don't introduce NewFD into scope; there's already something 5547 // with the same name in the same scope. 5548 } else if (II) { 5549 PushOnScopeChains(NewFD, S); 5550 } else 5551 Record->addDecl(NewFD); 5552 5553 return NewFD; 5554} 5555 5556/// \brief Build a new FieldDecl and check its well-formedness. 5557/// 5558/// This routine builds a new FieldDecl given the fields name, type, 5559/// record, etc. \p PrevDecl should refer to any previous declaration 5560/// with the same name and in the same scope as the field to be 5561/// created. 5562/// 5563/// \returns a new FieldDecl. 5564/// 5565/// \todo The Declarator argument is a hack. It will be removed once 5566FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5567 TypeSourceInfo *TInfo, 5568 RecordDecl *Record, SourceLocation Loc, 5569 bool Mutable, Expr *BitWidth, 5570 SourceLocation TSSL, 5571 AccessSpecifier AS, NamedDecl *PrevDecl, 5572 Declarator *D) { 5573 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5574 bool InvalidDecl = false; 5575 if (D) InvalidDecl = D->isInvalidType(); 5576 5577 // If we receive a broken type, recover by assuming 'int' and 5578 // marking this declaration as invalid. 5579 if (T.isNull()) { 5580 InvalidDecl = true; 5581 T = Context.IntTy; 5582 } 5583 5584 QualType EltTy = Context.getBaseElementType(T); 5585 if (!EltTy->isDependentType() && 5586 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5587 InvalidDecl = true; 5588 5589 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5590 // than a variably modified type. 5591 if (!InvalidDecl && T->isVariablyModifiedType()) { 5592 bool SizeIsNegative; 5593 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5594 SizeIsNegative); 5595 if (!FixedTy.isNull()) { 5596 Diag(Loc, diag::warn_illegal_constant_array_size); 5597 T = FixedTy; 5598 } else { 5599 if (SizeIsNegative) 5600 Diag(Loc, diag::err_typecheck_negative_array_size); 5601 else 5602 Diag(Loc, diag::err_typecheck_field_variable_size); 5603 InvalidDecl = true; 5604 } 5605 } 5606 5607 // Fields can not have abstract class types 5608 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5609 diag::err_abstract_type_in_decl, 5610 AbstractFieldType)) 5611 InvalidDecl = true; 5612 5613 bool ZeroWidth = false; 5614 // If this is declared as a bit-field, check the bit-field. 5615 if (!InvalidDecl && BitWidth && 5616 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5617 InvalidDecl = true; 5618 DeleteExpr(BitWidth); 5619 BitWidth = 0; 5620 ZeroWidth = false; 5621 } 5622 5623 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5624 BitWidth, Mutable); 5625 if (InvalidDecl) 5626 NewFD->setInvalidDecl(); 5627 5628 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5629 Diag(Loc, diag::err_duplicate_member) << II; 5630 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5631 NewFD->setInvalidDecl(); 5632 } 5633 5634 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5635 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5636 5637 if (!T->isPODType()) 5638 CXXRecord->setPOD(false); 5639 if (!ZeroWidth) 5640 CXXRecord->setEmpty(false); 5641 5642 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5643 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5644 5645 if (!RDecl->hasTrivialConstructor()) 5646 CXXRecord->setHasTrivialConstructor(false); 5647 if (!RDecl->hasTrivialCopyConstructor()) 5648 CXXRecord->setHasTrivialCopyConstructor(false); 5649 if (!RDecl->hasTrivialCopyAssignment()) 5650 CXXRecord->setHasTrivialCopyAssignment(false); 5651 if (!RDecl->hasTrivialDestructor()) 5652 CXXRecord->setHasTrivialDestructor(false); 5653 5654 // C++ 9.5p1: An object of a class with a non-trivial 5655 // constructor, a non-trivial copy constructor, a non-trivial 5656 // destructor, or a non-trivial copy assignment operator 5657 // cannot be a member of a union, nor can an array of such 5658 // objects. 5659 // TODO: C++0x alters this restriction significantly. 5660 if (Record->isUnion()) { 5661 // We check for copy constructors before constructors 5662 // because otherwise we'll never get complaints about 5663 // copy constructors. 5664 5665 CXXSpecialMember member = CXXInvalid; 5666 if (!RDecl->hasTrivialCopyConstructor()) 5667 member = CXXCopyConstructor; 5668 else if (!RDecl->hasTrivialConstructor()) 5669 member = CXXConstructor; 5670 else if (!RDecl->hasTrivialCopyAssignment()) 5671 member = CXXCopyAssignment; 5672 else if (!RDecl->hasTrivialDestructor()) 5673 member = CXXDestructor; 5674 5675 if (member != CXXInvalid) { 5676 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5677 DiagnoseNontrivial(RT, member); 5678 NewFD->setInvalidDecl(); 5679 } 5680 } 5681 } 5682 } 5683 5684 // FIXME: We need to pass in the attributes given an AST 5685 // representation, not a parser representation. 5686 if (D) 5687 // FIXME: What to pass instead of TUScope? 5688 ProcessDeclAttributes(TUScope, NewFD, *D); 5689 5690 if (T.isObjCGCWeak()) 5691 Diag(Loc, diag::warn_attribute_weak_on_field); 5692 5693 NewFD->setAccess(AS); 5694 5695 // C++ [dcl.init.aggr]p1: 5696 // An aggregate is an array or a class (clause 9) with [...] no 5697 // private or protected non-static data members (clause 11). 5698 // A POD must be an aggregate. 5699 if (getLangOptions().CPlusPlus && 5700 (AS == AS_private || AS == AS_protected)) { 5701 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5702 CXXRecord->setAggregate(false); 5703 CXXRecord->setPOD(false); 5704 } 5705 5706 return NewFD; 5707} 5708 5709/// DiagnoseNontrivial - Given that a class has a non-trivial 5710/// special member, figure out why. 5711void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5712 QualType QT(T, 0U); 5713 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5714 5715 // Check whether the member was user-declared. 5716 switch (member) { 5717 case CXXInvalid: 5718 break; 5719 5720 case CXXConstructor: 5721 if (RD->hasUserDeclaredConstructor()) { 5722 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5723 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5724 const FunctionDecl *body = 0; 5725 ci->getBody(body); 5726 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5727 SourceLocation CtorLoc = ci->getLocation(); 5728 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5729 return; 5730 } 5731 } 5732 5733 assert(0 && "found no user-declared constructors"); 5734 return; 5735 } 5736 break; 5737 5738 case CXXCopyConstructor: 5739 if (RD->hasUserDeclaredCopyConstructor()) { 5740 SourceLocation CtorLoc = 5741 RD->getCopyConstructor(Context, 0)->getLocation(); 5742 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5743 return; 5744 } 5745 break; 5746 5747 case CXXCopyAssignment: 5748 if (RD->hasUserDeclaredCopyAssignment()) { 5749 // FIXME: this should use the location of the copy 5750 // assignment, not the type. 5751 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5752 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5753 return; 5754 } 5755 break; 5756 5757 case CXXDestructor: 5758 if (RD->hasUserDeclaredDestructor()) { 5759 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5760 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5761 return; 5762 } 5763 break; 5764 } 5765 5766 typedef CXXRecordDecl::base_class_iterator base_iter; 5767 5768 // Virtual bases and members inhibit trivial copying/construction, 5769 // but not trivial destruction. 5770 if (member != CXXDestructor) { 5771 // Check for virtual bases. vbases includes indirect virtual bases, 5772 // so we just iterate through the direct bases. 5773 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5774 if (bi->isVirtual()) { 5775 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5776 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5777 return; 5778 } 5779 5780 // Check for virtual methods. 5781 typedef CXXRecordDecl::method_iterator meth_iter; 5782 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5783 ++mi) { 5784 if (mi->isVirtual()) { 5785 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5786 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5787 return; 5788 } 5789 } 5790 } 5791 5792 bool (CXXRecordDecl::*hasTrivial)() const; 5793 switch (member) { 5794 case CXXConstructor: 5795 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5796 case CXXCopyConstructor: 5797 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5798 case CXXCopyAssignment: 5799 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5800 case CXXDestructor: 5801 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5802 default: 5803 assert(0 && "unexpected special member"); return; 5804 } 5805 5806 // Check for nontrivial bases (and recurse). 5807 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5808 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5809 assert(BaseRT && "Don't know how to handle dependent bases"); 5810 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5811 if (!(BaseRecTy->*hasTrivial)()) { 5812 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5813 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5814 DiagnoseNontrivial(BaseRT, member); 5815 return; 5816 } 5817 } 5818 5819 // Check for nontrivial members (and recurse). 5820 typedef RecordDecl::field_iterator field_iter; 5821 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5822 ++fi) { 5823 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5824 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5825 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5826 5827 if (!(EltRD->*hasTrivial)()) { 5828 SourceLocation FLoc = (*fi)->getLocation(); 5829 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5830 DiagnoseNontrivial(EltRT, member); 5831 return; 5832 } 5833 } 5834 } 5835 5836 assert(0 && "found no explanation for non-trivial member"); 5837} 5838 5839/// TranslateIvarVisibility - Translate visibility from a token ID to an 5840/// AST enum value. 5841static ObjCIvarDecl::AccessControl 5842TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5843 switch (ivarVisibility) { 5844 default: assert(0 && "Unknown visitibility kind"); 5845 case tok::objc_private: return ObjCIvarDecl::Private; 5846 case tok::objc_public: return ObjCIvarDecl::Public; 5847 case tok::objc_protected: return ObjCIvarDecl::Protected; 5848 case tok::objc_package: return ObjCIvarDecl::Package; 5849 } 5850} 5851 5852/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5853/// in order to create an IvarDecl object for it. 5854Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5855 SourceLocation DeclStart, 5856 DeclPtrTy IntfDecl, 5857 Declarator &D, ExprTy *BitfieldWidth, 5858 tok::ObjCKeywordKind Visibility) { 5859 5860 IdentifierInfo *II = D.getIdentifier(); 5861 Expr *BitWidth = (Expr*)BitfieldWidth; 5862 SourceLocation Loc = DeclStart; 5863 if (II) Loc = D.getIdentifierLoc(); 5864 5865 // FIXME: Unnamed fields can be handled in various different ways, for 5866 // example, unnamed unions inject all members into the struct namespace! 5867 5868 TypeSourceInfo *TInfo = 0; 5869 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5870 5871 if (BitWidth) { 5872 // 6.7.2.1p3, 6.7.2.1p4 5873 if (VerifyBitField(Loc, II, T, BitWidth)) { 5874 D.setInvalidType(); 5875 DeleteExpr(BitWidth); 5876 BitWidth = 0; 5877 } 5878 } else { 5879 // Not a bitfield. 5880 5881 // validate II. 5882 5883 } 5884 if (T->isReferenceType()) { 5885 Diag(Loc, diag::err_ivar_reference_type); 5886 D.setInvalidType(); 5887 } 5888 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5889 // than a variably modified type. 5890 else if (T->isVariablyModifiedType()) { 5891 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5892 D.setInvalidType(); 5893 } 5894 5895 // Get the visibility (access control) for this ivar. 5896 ObjCIvarDecl::AccessControl ac = 5897 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5898 : ObjCIvarDecl::None; 5899 // Must set ivar's DeclContext to its enclosing interface. 5900 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 5901 ObjCContainerDecl *EnclosingContext; 5902 if (ObjCImplementationDecl *IMPDecl = 5903 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5904 // Case of ivar declared in an implementation. Context is that of its class. 5905 EnclosingContext = IMPDecl->getClassInterface(); 5906 assert(EnclosingContext && "Implementation has no class interface!"); 5907 } else { 5908 if (ObjCCategoryDecl *CDecl = 5909 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 5910 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 5911 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 5912 return DeclPtrTy(); 5913 } 5914 } 5915 EnclosingContext = EnclosingDecl; 5916 } 5917 5918 // Construct the decl. 5919 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5920 EnclosingContext, Loc, II, T, 5921 TInfo, ac, (Expr *)BitfieldWidth); 5922 5923 if (II) { 5924 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5925 ForRedeclaration); 5926 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5927 && !isa<TagDecl>(PrevDecl)) { 5928 Diag(Loc, diag::err_duplicate_member) << II; 5929 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5930 NewID->setInvalidDecl(); 5931 } 5932 } 5933 5934 // Process attributes attached to the ivar. 5935 ProcessDeclAttributes(S, NewID, D); 5936 5937 if (D.isInvalidType()) 5938 NewID->setInvalidDecl(); 5939 5940 if (II) { 5941 // FIXME: When interfaces are DeclContexts, we'll need to add 5942 // these to the interface. 5943 S->AddDecl(DeclPtrTy::make(NewID)); 5944 IdResolver.AddDecl(NewID); 5945 } 5946 5947 return DeclPtrTy::make(NewID); 5948} 5949 5950void Sema::ActOnFields(Scope* S, 5951 SourceLocation RecLoc, DeclPtrTy RecDecl, 5952 DeclPtrTy *Fields, unsigned NumFields, 5953 SourceLocation LBrac, SourceLocation RBrac, 5954 AttributeList *Attr) { 5955 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5956 assert(EnclosingDecl && "missing record or interface decl"); 5957 5958 // If the decl this is being inserted into is invalid, then it may be a 5959 // redeclaration or some other bogus case. Don't try to add fields to it. 5960 if (EnclosingDecl->isInvalidDecl()) { 5961 // FIXME: Deallocate fields? 5962 return; 5963 } 5964 5965 5966 // Verify that all the fields are okay. 5967 unsigned NumNamedMembers = 0; 5968 llvm::SmallVector<FieldDecl*, 32> RecFields; 5969 5970 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5971 for (unsigned i = 0; i != NumFields; ++i) { 5972 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5973 5974 // Get the type for the field. 5975 Type *FDTy = FD->getType().getTypePtr(); 5976 5977 if (!FD->isAnonymousStructOrUnion()) { 5978 // Remember all fields written by the user. 5979 RecFields.push_back(FD); 5980 } 5981 5982 // If the field is already invalid for some reason, don't emit more 5983 // diagnostics about it. 5984 if (FD->isInvalidDecl()) { 5985 EnclosingDecl->setInvalidDecl(); 5986 continue; 5987 } 5988 5989 // C99 6.7.2.1p2: 5990 // A structure or union shall not contain a member with 5991 // incomplete or function type (hence, a structure shall not 5992 // contain an instance of itself, but may contain a pointer to 5993 // an instance of itself), except that the last member of a 5994 // structure with more than one named member may have incomplete 5995 // array type; such a structure (and any union containing, 5996 // possibly recursively, a member that is such a structure) 5997 // shall not be a member of a structure or an element of an 5998 // array. 5999 if (FDTy->isFunctionType()) { 6000 // Field declared as a function. 6001 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6002 << FD->getDeclName(); 6003 FD->setInvalidDecl(); 6004 EnclosingDecl->setInvalidDecl(); 6005 continue; 6006 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6007 Record && Record->isStruct()) { 6008 // Flexible array member. 6009 if (NumNamedMembers < 1) { 6010 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6011 << FD->getDeclName(); 6012 FD->setInvalidDecl(); 6013 EnclosingDecl->setInvalidDecl(); 6014 continue; 6015 } 6016 // Okay, we have a legal flexible array member at the end of the struct. 6017 if (Record) 6018 Record->setHasFlexibleArrayMember(true); 6019 } else if (!FDTy->isDependentType() && 6020 RequireCompleteType(FD->getLocation(), FD->getType(), 6021 diag::err_field_incomplete)) { 6022 // Incomplete type 6023 FD->setInvalidDecl(); 6024 EnclosingDecl->setInvalidDecl(); 6025 continue; 6026 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6027 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6028 // If this is a member of a union, then entire union becomes "flexible". 6029 if (Record && Record->isUnion()) { 6030 Record->setHasFlexibleArrayMember(true); 6031 } else { 6032 // If this is a struct/class and this is not the last element, reject 6033 // it. Note that GCC supports variable sized arrays in the middle of 6034 // structures. 6035 if (i != NumFields-1) 6036 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6037 << FD->getDeclName() << FD->getType(); 6038 else { 6039 // We support flexible arrays at the end of structs in 6040 // other structs as an extension. 6041 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6042 << FD->getDeclName(); 6043 if (Record) 6044 Record->setHasFlexibleArrayMember(true); 6045 } 6046 } 6047 } 6048 if (Record && FDTTy->getDecl()->hasObjectMember()) 6049 Record->setHasObjectMember(true); 6050 } else if (FDTy->isObjCInterfaceType()) { 6051 /// A field cannot be an Objective-c object 6052 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6053 FD->setInvalidDecl(); 6054 EnclosingDecl->setInvalidDecl(); 6055 continue; 6056 } else if (getLangOptions().ObjC1 && 6057 getLangOptions().getGCMode() != LangOptions::NonGC && 6058 Record && 6059 (FD->getType()->isObjCObjectPointerType() || 6060 FD->getType().isObjCGCStrong())) 6061 Record->setHasObjectMember(true); 6062 // Keep track of the number of named members. 6063 if (FD->getIdentifier()) 6064 ++NumNamedMembers; 6065 } 6066 6067 // Okay, we successfully defined 'Record'. 6068 if (Record) { 6069 Record->completeDefinition(); 6070 } else { 6071 ObjCIvarDecl **ClsFields = 6072 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6073 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6074 ID->setLocEnd(RBrac); 6075 // Add ivar's to class's DeclContext. 6076 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6077 ClsFields[i]->setLexicalDeclContext(ID); 6078 ID->addDecl(ClsFields[i]); 6079 } 6080 // Must enforce the rule that ivars in the base classes may not be 6081 // duplicates. 6082 if (ID->getSuperClass()) 6083 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6084 } else if (ObjCImplementationDecl *IMPDecl = 6085 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6086 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6087 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6088 // Ivar declared in @implementation never belongs to the implementation. 6089 // Only it is in implementation's lexical context. 6090 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6091 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6092 } else if (ObjCCategoryDecl *CDecl = 6093 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6094 // case of ivars in class extension; all other cases have been 6095 // reported as errors elsewhere. 6096 // FIXME. Class extension does not have a LocEnd field. 6097 // CDecl->setLocEnd(RBrac); 6098 // Add ivar's to class extension's DeclContext. 6099 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6100 ClsFields[i]->setLexicalDeclContext(CDecl); 6101 CDecl->addDecl(ClsFields[i]); 6102 } 6103 } 6104 } 6105 6106 if (Attr) 6107 ProcessDeclAttributeList(S, Record, Attr); 6108} 6109 6110/// \brief Determine whether the given integral value is representable within 6111/// the given type T. 6112static bool isRepresentableIntegerValue(ASTContext &Context, 6113 llvm::APSInt &Value, 6114 QualType T) { 6115 assert(T->isIntegralType() && "Integral type required!"); 6116 unsigned BitWidth = Context.getIntWidth(T); 6117 6118 if (Value.isUnsigned() || Value.isNonNegative()) 6119 return Value.getActiveBits() < BitWidth; 6120 6121 return Value.getMinSignedBits() <= BitWidth; 6122} 6123 6124// \brief Given an integral type, return the next larger integral type 6125// (or a NULL type of no such type exists). 6126static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6127 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6128 // enum checking below. 6129 assert(T->isIntegralType() && "Integral type required!"); 6130 const unsigned NumTypes = 4; 6131 QualType SignedIntegralTypes[NumTypes] = { 6132 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6133 }; 6134 QualType UnsignedIntegralTypes[NumTypes] = { 6135 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6136 Context.UnsignedLongLongTy 6137 }; 6138 6139 unsigned BitWidth = Context.getTypeSize(T); 6140 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6141 : UnsignedIntegralTypes; 6142 for (unsigned I = 0; I != NumTypes; ++I) 6143 if (Context.getTypeSize(Types[I]) > BitWidth) 6144 return Types[I]; 6145 6146 return QualType(); 6147} 6148 6149EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6150 EnumConstantDecl *LastEnumConst, 6151 SourceLocation IdLoc, 6152 IdentifierInfo *Id, 6153 ExprArg val) { 6154 Expr *Val = (Expr *)val.get(); 6155 6156 unsigned IntWidth = Context.Target.getIntWidth(); 6157 llvm::APSInt EnumVal(IntWidth); 6158 QualType EltTy; 6159 if (Val) { 6160 if (Enum->isDependentType() || Val->isTypeDependent()) 6161 EltTy = Context.DependentTy; 6162 else { 6163 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6164 SourceLocation ExpLoc; 6165 if (!Val->isValueDependent() && 6166 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6167 Val = 0; 6168 } else { 6169 if (!getLangOptions().CPlusPlus) { 6170 // C99 6.7.2.2p2: 6171 // The expression that defines the value of an enumeration constant 6172 // shall be an integer constant expression that has a value 6173 // representable as an int. 6174 6175 // Complain if the value is not representable in an int. 6176 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6177 Diag(IdLoc, diag::ext_enum_value_not_int) 6178 << EnumVal.toString(10) << Val->getSourceRange() 6179 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6180 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6181 // Force the type of the expression to 'int'. 6182 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6183 6184 if (Val != val.get()) { 6185 val.release(); 6186 val = Val; 6187 } 6188 } 6189 } 6190 6191 // C++0x [dcl.enum]p5: 6192 // If the underlying type is not fixed, the type of each enumerator 6193 // is the type of its initializing value: 6194 // - If an initializer is specified for an enumerator, the 6195 // initializing value has the same type as the expression. 6196 EltTy = Val->getType(); 6197 } 6198 } 6199 } 6200 6201 if (!Val) { 6202 if (Enum->isDependentType()) 6203 EltTy = Context.DependentTy; 6204 else if (!LastEnumConst) { 6205 // C++0x [dcl.enum]p5: 6206 // If the underlying type is not fixed, the type of each enumerator 6207 // is the type of its initializing value: 6208 // - If no initializer is specified for the first enumerator, the 6209 // initializing value has an unspecified integral type. 6210 // 6211 // GCC uses 'int' for its unspecified integral type, as does 6212 // C99 6.7.2.2p3. 6213 EltTy = Context.IntTy; 6214 } else { 6215 // Assign the last value + 1. 6216 EnumVal = LastEnumConst->getInitVal(); 6217 ++EnumVal; 6218 EltTy = LastEnumConst->getType(); 6219 6220 // Check for overflow on increment. 6221 if (EnumVal < LastEnumConst->getInitVal()) { 6222 // C++0x [dcl.enum]p5: 6223 // If the underlying type is not fixed, the type of each enumerator 6224 // is the type of its initializing value: 6225 // 6226 // - Otherwise the type of the initializing value is the same as 6227 // the type of the initializing value of the preceding enumerator 6228 // unless the incremented value is not representable in that type, 6229 // in which case the type is an unspecified integral type 6230 // sufficient to contain the incremented value. If no such type 6231 // exists, the program is ill-formed. 6232 QualType T = getNextLargerIntegralType(Context, EltTy); 6233 if (T.isNull()) { 6234 // There is no integral type larger enough to represent this 6235 // value. Complain, then allow the value to wrap around. 6236 EnumVal = LastEnumConst->getInitVal(); 6237 EnumVal.zext(EnumVal.getBitWidth() * 2); 6238 Diag(IdLoc, diag::warn_enumerator_too_large) 6239 << EnumVal.toString(10); 6240 } else { 6241 EltTy = T; 6242 } 6243 6244 // Retrieve the last enumerator's value, extent that type to the 6245 // type that is supposed to be large enough to represent the incremented 6246 // value, then increment. 6247 EnumVal = LastEnumConst->getInitVal(); 6248 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6249 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6250 ++EnumVal; 6251 6252 // If we're not in C++, diagnose the overflow of enumerator values, 6253 // which in C99 means that the enumerator value is not representable in 6254 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6255 // permits enumerator values that are representable in some larger 6256 // integral type. 6257 if (!getLangOptions().CPlusPlus && !T.isNull()) 6258 Diag(IdLoc, diag::warn_enum_value_overflow); 6259 } else if (!getLangOptions().CPlusPlus && 6260 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6261 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6262 Diag(IdLoc, diag::ext_enum_value_not_int) 6263 << EnumVal.toString(10) << 1; 6264 } 6265 } 6266 } 6267 6268 if (!EltTy->isDependentType()) { 6269 // Make the enumerator value match the signedness and size of the 6270 // enumerator's type. 6271 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6272 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6273 } 6274 6275 val.release(); 6276 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6277 Val, EnumVal); 6278} 6279 6280 6281Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6282 DeclPtrTy lastEnumConst, 6283 SourceLocation IdLoc, 6284 IdentifierInfo *Id, 6285 SourceLocation EqualLoc, ExprTy *val) { 6286 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6287 EnumConstantDecl *LastEnumConst = 6288 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6289 Expr *Val = static_cast<Expr*>(val); 6290 6291 // The scope passed in may not be a decl scope. Zip up the scope tree until 6292 // we find one that is. 6293 S = getNonFieldDeclScope(S); 6294 6295 // Verify that there isn't already something declared with this name in this 6296 // scope. 6297 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6298 ForRedeclaration); 6299 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6300 // Maybe we will complain about the shadowed template parameter. 6301 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6302 // Just pretend that we didn't see the previous declaration. 6303 PrevDecl = 0; 6304 } 6305 6306 if (PrevDecl) { 6307 // When in C++, we may get a TagDecl with the same name; in this case the 6308 // enum constant will 'hide' the tag. 6309 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6310 "Received TagDecl when not in C++!"); 6311 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6312 if (isa<EnumConstantDecl>(PrevDecl)) 6313 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6314 else 6315 Diag(IdLoc, diag::err_redefinition) << Id; 6316 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6317 if (Val) Val->Destroy(Context); 6318 return DeclPtrTy(); 6319 } 6320 } 6321 6322 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6323 IdLoc, Id, Owned(Val)); 6324 6325 // Register this decl in the current scope stack. 6326 if (New) { 6327 New->setAccess(TheEnumDecl->getAccess()); 6328 PushOnScopeChains(New, S); 6329 } 6330 6331 return DeclPtrTy::make(New); 6332} 6333 6334void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6335 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6336 DeclPtrTy *Elements, unsigned NumElements, 6337 Scope *S, AttributeList *Attr) { 6338 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6339 QualType EnumType = Context.getTypeDeclType(Enum); 6340 6341 if (Attr) 6342 ProcessDeclAttributeList(S, Enum, Attr); 6343 6344 if (Enum->isDependentType()) { 6345 for (unsigned i = 0; i != NumElements; ++i) { 6346 EnumConstantDecl *ECD = 6347 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6348 if (!ECD) continue; 6349 6350 ECD->setType(EnumType); 6351 } 6352 6353 Enum->completeDefinition(Context.DependentTy, Context.DependentTy); 6354 return; 6355 } 6356 6357 // TODO: If the result value doesn't fit in an int, it must be a long or long 6358 // long value. ISO C does not support this, but GCC does as an extension, 6359 // emit a warning. 6360 unsigned IntWidth = Context.Target.getIntWidth(); 6361 unsigned CharWidth = Context.Target.getCharWidth(); 6362 unsigned ShortWidth = Context.Target.getShortWidth(); 6363 6364 // Verify that all the values are okay, compute the size of the values, and 6365 // reverse the list. 6366 unsigned NumNegativeBits = 0; 6367 unsigned NumPositiveBits = 0; 6368 6369 // Keep track of whether all elements have type int. 6370 bool AllElementsInt = true; 6371 6372 for (unsigned i = 0; i != NumElements; ++i) { 6373 EnumConstantDecl *ECD = 6374 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6375 if (!ECD) continue; // Already issued a diagnostic. 6376 6377 const llvm::APSInt &InitVal = ECD->getInitVal(); 6378 6379 // Keep track of the size of positive and negative values. 6380 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6381 NumPositiveBits = std::max(NumPositiveBits, 6382 (unsigned)InitVal.getActiveBits()); 6383 else 6384 NumNegativeBits = std::max(NumNegativeBits, 6385 (unsigned)InitVal.getMinSignedBits()); 6386 6387 // Keep track of whether every enum element has type int (very commmon). 6388 if (AllElementsInt) 6389 AllElementsInt = ECD->getType() == Context.IntTy; 6390 } 6391 6392 // Figure out the type that should be used for this enum. 6393 // FIXME: Support -fshort-enums. 6394 QualType BestType; 6395 unsigned BestWidth; 6396 6397 // C++0x N3000 [conv.prom]p3: 6398 // An rvalue of an unscoped enumeration type whose underlying 6399 // type is not fixed can be converted to an rvalue of the first 6400 // of the following types that can represent all the values of 6401 // the enumeration: int, unsigned int, long int, unsigned long 6402 // int, long long int, or unsigned long long int. 6403 // C99 6.4.4.3p2: 6404 // An identifier declared as an enumeration constant has type int. 6405 // The C99 rule is modified by a gcc extension 6406 QualType BestPromotionType; 6407 6408 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6409 6410 if (NumNegativeBits) { 6411 // If there is a negative value, figure out the smallest integer type (of 6412 // int/long/longlong) that fits. 6413 // If it's packed, check also if it fits a char or a short. 6414 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6415 BestType = Context.SignedCharTy; 6416 BestWidth = CharWidth; 6417 } else if (Packed && NumNegativeBits <= ShortWidth && 6418 NumPositiveBits < ShortWidth) { 6419 BestType = Context.ShortTy; 6420 BestWidth = ShortWidth; 6421 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6422 BestType = Context.IntTy; 6423 BestWidth = IntWidth; 6424 } else { 6425 BestWidth = Context.Target.getLongWidth(); 6426 6427 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6428 BestType = Context.LongTy; 6429 } else { 6430 BestWidth = Context.Target.getLongLongWidth(); 6431 6432 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6433 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6434 BestType = Context.LongLongTy; 6435 } 6436 } 6437 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6438 } else { 6439 // If there is no negative value, figure out the smallest type that fits 6440 // all of the enumerator values. 6441 // If it's packed, check also if it fits a char or a short. 6442 if (Packed && NumPositiveBits <= CharWidth) { 6443 BestType = Context.UnsignedCharTy; 6444 BestPromotionType = Context.IntTy; 6445 BestWidth = CharWidth; 6446 } else if (Packed && NumPositiveBits <= ShortWidth) { 6447 BestType = Context.UnsignedShortTy; 6448 BestPromotionType = Context.IntTy; 6449 BestWidth = ShortWidth; 6450 } else if (NumPositiveBits <= IntWidth) { 6451 BestType = Context.UnsignedIntTy; 6452 BestWidth = IntWidth; 6453 BestPromotionType 6454 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6455 ? Context.UnsignedIntTy : Context.IntTy; 6456 } else if (NumPositiveBits <= 6457 (BestWidth = Context.Target.getLongWidth())) { 6458 BestType = Context.UnsignedLongTy; 6459 BestPromotionType 6460 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6461 ? Context.UnsignedLongTy : Context.LongTy; 6462 } else { 6463 BestWidth = Context.Target.getLongLongWidth(); 6464 assert(NumPositiveBits <= BestWidth && 6465 "How could an initializer get larger than ULL?"); 6466 BestType = Context.UnsignedLongLongTy; 6467 BestPromotionType 6468 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6469 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6470 } 6471 } 6472 6473 // Loop over all of the enumerator constants, changing their types to match 6474 // the type of the enum if needed. 6475 for (unsigned i = 0; i != NumElements; ++i) { 6476 EnumConstantDecl *ECD = 6477 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6478 if (!ECD) continue; // Already issued a diagnostic. 6479 6480 // Standard C says the enumerators have int type, but we allow, as an 6481 // extension, the enumerators to be larger than int size. If each 6482 // enumerator value fits in an int, type it as an int, otherwise type it the 6483 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6484 // that X has type 'int', not 'unsigned'. 6485 6486 // Determine whether the value fits into an int. 6487 llvm::APSInt InitVal = ECD->getInitVal(); 6488 6489 // If it fits into an integer type, force it. Otherwise force it to match 6490 // the enum decl type. 6491 QualType NewTy; 6492 unsigned NewWidth; 6493 bool NewSign; 6494 if (!getLangOptions().CPlusPlus && 6495 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6496 NewTy = Context.IntTy; 6497 NewWidth = IntWidth; 6498 NewSign = true; 6499 } else if (ECD->getType() == BestType) { 6500 // Already the right type! 6501 if (getLangOptions().CPlusPlus) 6502 // C++ [dcl.enum]p4: Following the closing brace of an 6503 // enum-specifier, each enumerator has the type of its 6504 // enumeration. 6505 ECD->setType(EnumType); 6506 continue; 6507 } else { 6508 NewTy = BestType; 6509 NewWidth = BestWidth; 6510 NewSign = BestType->isSignedIntegerType(); 6511 } 6512 6513 // Adjust the APSInt value. 6514 InitVal.extOrTrunc(NewWidth); 6515 InitVal.setIsSigned(NewSign); 6516 ECD->setInitVal(InitVal); 6517 6518 // Adjust the Expr initializer and type. 6519 if (ECD->getInitExpr()) 6520 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6521 CastExpr::CK_IntegralCast, 6522 ECD->getInitExpr(), 6523 CXXBaseSpecifierArray(), 6524 /*isLvalue=*/false)); 6525 if (getLangOptions().CPlusPlus) 6526 // C++ [dcl.enum]p4: Following the closing brace of an 6527 // enum-specifier, each enumerator has the type of its 6528 // enumeration. 6529 ECD->setType(EnumType); 6530 else 6531 ECD->setType(NewTy); 6532 } 6533 6534 Enum->completeDefinition(BestType, BestPromotionType); 6535} 6536 6537Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6538 ExprArg expr) { 6539 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6540 6541 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6542 Loc, AsmString); 6543 CurContext->addDecl(New); 6544 return DeclPtrTy::make(New); 6545} 6546 6547void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6548 SourceLocation PragmaLoc, 6549 SourceLocation NameLoc) { 6550 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6551 6552 if (PrevDecl) { 6553 PrevDecl->addAttr(::new (Context) WeakAttr()); 6554 } else { 6555 (void)WeakUndeclaredIdentifiers.insert( 6556 std::pair<IdentifierInfo*,WeakInfo> 6557 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6558 } 6559} 6560 6561void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6562 IdentifierInfo* AliasName, 6563 SourceLocation PragmaLoc, 6564 SourceLocation NameLoc, 6565 SourceLocation AliasNameLoc) { 6566 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6567 LookupOrdinaryName); 6568 WeakInfo W = WeakInfo(Name, NameLoc); 6569 6570 if (PrevDecl) { 6571 if (!PrevDecl->hasAttr<AliasAttr>()) 6572 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6573 DeclApplyPragmaWeak(TUScope, ND, W); 6574 } else { 6575 (void)WeakUndeclaredIdentifiers.insert( 6576 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6577 } 6578} 6579