SemaDecl.cpp revision 515ddd8f7a36fc2684492c13665642153fc690c0
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(), II, 94 SourceLocation(), SS->getRange(), NameLoc 95 ).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && 102 RequireCompleteDeclContext(*SS, LookupCtx)) 103 return 0; 104 } 105 106 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 107 // lookup for class-names. 108 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 109 LookupOrdinaryName; 110 LookupResult Result(*this, &II, NameLoc, Kind); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::NotFoundInCurrentInstantiation: 136 case LookupResult::FoundOverloaded: 137 case LookupResult::FoundUnresolvedValue: 138 Result.suppressDiagnostics(); 139 return 0; 140 141 case LookupResult::Ambiguous: 142 // Recover from type-hiding ambiguities by hiding the type. We'll 143 // do the lookup again when looking for an object, and we can 144 // diagnose the error then. If we don't do this, then the error 145 // about hiding the type will be immediately followed by an error 146 // that only makes sense if the identifier was treated like a type. 147 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 148 Result.suppressDiagnostics(); 149 return 0; 150 } 151 152 // Look to see if we have a type anywhere in the list of results. 153 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 154 Res != ResEnd; ++Res) { 155 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 156 if (!IIDecl || 157 (*Res)->getLocation().getRawEncoding() < 158 IIDecl->getLocation().getRawEncoding()) 159 IIDecl = *Res; 160 } 161 } 162 163 if (!IIDecl) { 164 // None of the entities we found is a type, so there is no way 165 // to even assume that the result is a type. In this case, don't 166 // complain about the ambiguity. The parser will either try to 167 // perform this lookup again (e.g., as an object name), which 168 // will produce the ambiguity, or will complain that it expected 169 // a type name. 170 Result.suppressDiagnostics(); 171 return 0; 172 } 173 174 // We found a type within the ambiguous lookup; diagnose the 175 // ambiguity and then return that type. This might be the right 176 // answer, or it might not be, but it suppresses any attempt to 177 // perform the name lookup again. 178 break; 179 180 case LookupResult::Found: 181 IIDecl = Result.getFoundDecl(); 182 break; 183 } 184 185 assert(IIDecl && "Didn't find decl"); 186 187 QualType T; 188 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 189 DiagnoseUseOfDecl(IIDecl, NameLoc); 190 191 if (T.isNull()) 192 T = Context.getTypeDeclType(TD); 193 194 if (SS) 195 T = getElaboratedType(ETK_None, *SS, T); 196 197 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 198 T = Context.getObjCInterfaceType(IDecl); 199 } else if (UnresolvedUsingTypenameDecl *UUDecl = 200 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 201 // FIXME: preserve source structure information. 202 T = Context.getDependentNameType(ETK_None, 203 UUDecl->getTargetNestedNameSpecifier(), 204 &II); 205 } else { 206 // If it's not plausibly a type, suppress diagnostics. 207 Result.suppressDiagnostics(); 208 return 0; 209 } 210 211 return T.getAsOpaquePtr(); 212} 213 214/// isTagName() - This method is called *for error recovery purposes only* 215/// to determine if the specified name is a valid tag name ("struct foo"). If 216/// so, this returns the TST for the tag corresponding to it (TST_enum, 217/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 218/// where the user forgot to specify the tag. 219DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 220 // Do a tag name lookup in this scope. 221 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 222 LookupName(R, S, false); 223 R.suppressDiagnostics(); 224 if (R.getResultKind() == LookupResult::Found) 225 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 226 switch (TD->getTagKind()) { 227 default: return DeclSpec::TST_unspecified; 228 case TTK_Struct: return DeclSpec::TST_struct; 229 case TTK_Union: return DeclSpec::TST_union; 230 case TTK_Class: return DeclSpec::TST_class; 231 case TTK_Enum: return DeclSpec::TST_enum; 232 } 233 } 234 235 return DeclSpec::TST_unspecified; 236} 237 238bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 239 SourceLocation IILoc, 240 Scope *S, 241 CXXScopeSpec *SS, 242 TypeTy *&SuggestedType) { 243 // We don't have anything to suggest (yet). 244 SuggestedType = 0; 245 246 // There may have been a typo in the name of the type. Look up typo 247 // results, in case we have something that we can suggest. 248 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 249 NotForRedeclaration); 250 251 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 252 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 253 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 254 !Result->isInvalidDecl()) { 255 // We found a similarly-named type or interface; suggest that. 256 if (!SS || !SS->isSet()) 257 Diag(IILoc, diag::err_unknown_typename_suggest) 258 << &II << Lookup.getLookupName() 259 << FixItHint::CreateReplacement(SourceRange(IILoc), 260 Result->getNameAsString()); 261 else if (DeclContext *DC = computeDeclContext(*SS, false)) 262 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 263 << &II << DC << Lookup.getLookupName() << SS->getRange() 264 << FixItHint::CreateReplacement(SourceRange(IILoc), 265 Result->getNameAsString()); 266 else 267 llvm_unreachable("could not have corrected a typo here"); 268 269 Diag(Result->getLocation(), diag::note_previous_decl) 270 << Result->getDeclName(); 271 272 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 273 return true; 274 } 275 } else if (Lookup.empty()) { 276 // We corrected to a keyword. 277 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 278 Diag(IILoc, diag::err_unknown_typename_suggest) 279 << &II << Corrected; 280 return true; 281 } 282 } 283 284 if (getLangOptions().CPlusPlus) { 285 // See if II is a class template that the user forgot to pass arguments to. 286 UnqualifiedId Name; 287 Name.setIdentifier(&II, IILoc); 288 CXXScopeSpec EmptySS; 289 TemplateTy TemplateResult; 290 bool MemberOfUnknownSpecialization; 291 if (isTemplateName(S, SS ? *SS : EmptySS, Name, 0, true, TemplateResult, 292 MemberOfUnknownSpecialization) == TNK_Type_template) { 293 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 294 Diag(IILoc, diag::err_template_missing_args) << TplName; 295 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 296 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 297 << TplDecl->getTemplateParameters()->getSourceRange(); 298 } 299 return true; 300 } 301 } 302 303 // FIXME: Should we move the logic that tries to recover from a missing tag 304 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 305 306 if (!SS || (!SS->isSet() && !SS->isInvalid())) 307 Diag(IILoc, diag::err_unknown_typename) << &II; 308 else if (DeclContext *DC = computeDeclContext(*SS, false)) 309 Diag(IILoc, diag::err_typename_nested_not_found) 310 << &II << DC << SS->getRange(); 311 else if (isDependentScopeSpecifier(*SS)) { 312 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 313 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 314 << SourceRange(SS->getRange().getBegin(), IILoc) 315 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 316 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 317 } else { 318 assert(SS && SS->isInvalid() && 319 "Invalid scope specifier has already been diagnosed"); 320 } 321 322 return true; 323} 324 325// Determines the context to return to after temporarily entering a 326// context. This depends in an unnecessarily complicated way on the 327// exact ordering of callbacks from the parser. 328DeclContext *Sema::getContainingDC(DeclContext *DC) { 329 330 // Functions defined inline within classes aren't parsed until we've 331 // finished parsing the top-level class, so the top-level class is 332 // the context we'll need to return to. 333 if (isa<FunctionDecl>(DC)) { 334 DC = DC->getLexicalParent(); 335 336 // A function not defined within a class will always return to its 337 // lexical context. 338 if (!isa<CXXRecordDecl>(DC)) 339 return DC; 340 341 // A C++ inline method/friend is parsed *after* the topmost class 342 // it was declared in is fully parsed ("complete"); the topmost 343 // class is the context we need to return to. 344 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 345 DC = RD; 346 347 // Return the declaration context of the topmost class the inline method is 348 // declared in. 349 return DC; 350 } 351 352 if (isa<ObjCMethodDecl>(DC)) 353 return Context.getTranslationUnitDecl(); 354 355 return DC->getLexicalParent(); 356} 357 358void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 359 assert(getContainingDC(DC) == CurContext && 360 "The next DeclContext should be lexically contained in the current one."); 361 CurContext = DC; 362 S->setEntity(DC); 363} 364 365void Sema::PopDeclContext() { 366 assert(CurContext && "DeclContext imbalance!"); 367 368 CurContext = getContainingDC(CurContext); 369} 370 371/// EnterDeclaratorContext - Used when we must lookup names in the context 372/// of a declarator's nested name specifier. 373/// 374void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 375 // C++0x [basic.lookup.unqual]p13: 376 // A name used in the definition of a static data member of class 377 // X (after the qualified-id of the static member) is looked up as 378 // if the name was used in a member function of X. 379 // C++0x [basic.lookup.unqual]p14: 380 // If a variable member of a namespace is defined outside of the 381 // scope of its namespace then any name used in the definition of 382 // the variable member (after the declarator-id) is looked up as 383 // if the definition of the variable member occurred in its 384 // namespace. 385 // Both of these imply that we should push a scope whose context 386 // is the semantic context of the declaration. We can't use 387 // PushDeclContext here because that context is not necessarily 388 // lexically contained in the current context. Fortunately, 389 // the containing scope should have the appropriate information. 390 391 assert(!S->getEntity() && "scope already has entity"); 392 393#ifndef NDEBUG 394 Scope *Ancestor = S->getParent(); 395 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 396 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 397#endif 398 399 CurContext = DC; 400 S->setEntity(DC); 401} 402 403void Sema::ExitDeclaratorContext(Scope *S) { 404 assert(S->getEntity() == CurContext && "Context imbalance!"); 405 406 // Switch back to the lexical context. The safety of this is 407 // enforced by an assert in EnterDeclaratorContext. 408 Scope *Ancestor = S->getParent(); 409 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 410 CurContext = (DeclContext*) Ancestor->getEntity(); 411 412 // We don't need to do anything with the scope, which is going to 413 // disappear. 414} 415 416/// \brief Determine whether we allow overloading of the function 417/// PrevDecl with another declaration. 418/// 419/// This routine determines whether overloading is possible, not 420/// whether some new function is actually an overload. It will return 421/// true in C++ (where we can always provide overloads) or, as an 422/// extension, in C when the previous function is already an 423/// overloaded function declaration or has the "overloadable" 424/// attribute. 425static bool AllowOverloadingOfFunction(LookupResult &Previous, 426 ASTContext &Context) { 427 if (Context.getLangOptions().CPlusPlus) 428 return true; 429 430 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 431 return true; 432 433 return (Previous.getResultKind() == LookupResult::Found 434 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 435} 436 437/// Add this decl to the scope shadowed decl chains. 438void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 439 // Move up the scope chain until we find the nearest enclosing 440 // non-transparent context. The declaration will be introduced into this 441 // scope. 442 while (S->getEntity() && 443 ((DeclContext *)S->getEntity())->isTransparentContext()) 444 S = S->getParent(); 445 446 // Add scoped declarations into their context, so that they can be 447 // found later. Declarations without a context won't be inserted 448 // into any context. 449 if (AddToContext) 450 CurContext->addDecl(D); 451 452 // Out-of-line definitions shouldn't be pushed into scope in C++. 453 // Out-of-line variable and function definitions shouldn't even in C. 454 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 455 D->isOutOfLine()) 456 return; 457 458 // Template instantiations should also not be pushed into scope. 459 if (isa<FunctionDecl>(D) && 460 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 461 return; 462 463 // If this replaces anything in the current scope, 464 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 465 IEnd = IdResolver.end(); 466 for (; I != IEnd; ++I) { 467 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 468 S->RemoveDecl(DeclPtrTy::make(*I)); 469 IdResolver.RemoveDecl(*I); 470 471 // Should only need to replace one decl. 472 break; 473 } 474 } 475 476 S->AddDecl(DeclPtrTy::make(D)); 477 IdResolver.AddDecl(D); 478} 479 480bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 481 return IdResolver.isDeclInScope(D, Ctx, Context, S); 482} 483 484static bool isOutOfScopePreviousDeclaration(NamedDecl *, 485 DeclContext*, 486 ASTContext&); 487 488/// Filters out lookup results that don't fall within the given scope 489/// as determined by isDeclInScope. 490static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 491 DeclContext *Ctx, Scope *S, 492 bool ConsiderLinkage) { 493 LookupResult::Filter F = R.makeFilter(); 494 while (F.hasNext()) { 495 NamedDecl *D = F.next(); 496 497 if (SemaRef.isDeclInScope(D, Ctx, S)) 498 continue; 499 500 if (ConsiderLinkage && 501 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 502 continue; 503 504 F.erase(); 505 } 506 507 F.done(); 508} 509 510static bool isUsingDecl(NamedDecl *D) { 511 return isa<UsingShadowDecl>(D) || 512 isa<UnresolvedUsingTypenameDecl>(D) || 513 isa<UnresolvedUsingValueDecl>(D); 514} 515 516/// Removes using shadow declarations from the lookup results. 517static void RemoveUsingDecls(LookupResult &R) { 518 LookupResult::Filter F = R.makeFilter(); 519 while (F.hasNext()) 520 if (isUsingDecl(F.next())) 521 F.erase(); 522 523 F.done(); 524} 525 526static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 527 if (D->isInvalidDecl()) 528 return false; 529 530 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 531 return false; 532 533 // White-list anything that isn't a local variable. 534 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 535 !D->getDeclContext()->isFunctionOrMethod()) 536 return false; 537 538 // Types of valid local variables should be complete, so this should succeed. 539 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 540 541 // White-list anything with an __attribute__((unused)) type. 542 QualType Ty = VD->getType(); 543 544 // Only look at the outermost level of typedef. 545 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 546 if (TT->getDecl()->hasAttr<UnusedAttr>()) 547 return false; 548 } 549 550 // If we failed to complete the type for some reason, or if the type is 551 // dependent, don't diagnose the variable. 552 if (Ty->isIncompleteType() || Ty->isDependentType()) 553 return false; 554 555 if (const TagType *TT = Ty->getAs<TagType>()) { 556 const TagDecl *Tag = TT->getDecl(); 557 if (Tag->hasAttr<UnusedAttr>()) 558 return false; 559 560 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 561 // FIXME: Checking for the presence of a user-declared constructor 562 // isn't completely accurate; we'd prefer to check that the initializer 563 // has no side effects. 564 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 565 return false; 566 } 567 } 568 569 // TODO: __attribute__((unused)) templates? 570 } 571 572 return true; 573} 574 575void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 576 if (!ShouldDiagnoseUnusedDecl(D)) 577 return; 578 579 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 580 Diag(D->getLocation(), diag::warn_unused_exception_param) 581 << D->getDeclName(); 582 else 583 Diag(D->getLocation(), diag::warn_unused_variable) 584 << D->getDeclName(); 585} 586 587void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 588 if (S->decl_empty()) return; 589 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 590 "Scope shouldn't contain decls!"); 591 592 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 593 I != E; ++I) { 594 Decl *TmpD = (*I).getAs<Decl>(); 595 assert(TmpD && "This decl didn't get pushed??"); 596 597 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 598 NamedDecl *D = cast<NamedDecl>(TmpD); 599 600 if (!D->getDeclName()) continue; 601 602 // Diagnose unused variables in this scope. 603 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 604 DiagnoseUnusedDecl(D); 605 606 // Remove this name from our lexical scope. 607 IdResolver.RemoveDecl(D); 608 } 609} 610 611/// \brief Look for an Objective-C class in the translation unit. 612/// 613/// \param Id The name of the Objective-C class we're looking for. If 614/// typo-correction fixes this name, the Id will be updated 615/// to the fixed name. 616/// 617/// \param IdLoc The location of the name in the translation unit. 618/// 619/// \param TypoCorrection If true, this routine will attempt typo correction 620/// if there is no class with the given name. 621/// 622/// \returns The declaration of the named Objective-C class, or NULL if the 623/// class could not be found. 624ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 625 SourceLocation IdLoc, 626 bool TypoCorrection) { 627 // The third "scope" argument is 0 since we aren't enabling lazy built-in 628 // creation from this context. 629 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 630 631 if (!IDecl && TypoCorrection) { 632 // Perform typo correction at the given location, but only if we 633 // find an Objective-C class name. 634 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 635 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 636 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 637 Diag(IdLoc, diag::err_undef_interface_suggest) 638 << Id << IDecl->getDeclName() 639 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 640 Diag(IDecl->getLocation(), diag::note_previous_decl) 641 << IDecl->getDeclName(); 642 643 Id = IDecl->getIdentifier(); 644 } 645 } 646 647 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 648} 649 650/// getNonFieldDeclScope - Retrieves the innermost scope, starting 651/// from S, where a non-field would be declared. This routine copes 652/// with the difference between C and C++ scoping rules in structs and 653/// unions. For example, the following code is well-formed in C but 654/// ill-formed in C++: 655/// @code 656/// struct S6 { 657/// enum { BAR } e; 658/// }; 659/// 660/// void test_S6() { 661/// struct S6 a; 662/// a.e = BAR; 663/// } 664/// @endcode 665/// For the declaration of BAR, this routine will return a different 666/// scope. The scope S will be the scope of the unnamed enumeration 667/// within S6. In C++, this routine will return the scope associated 668/// with S6, because the enumeration's scope is a transparent 669/// context but structures can contain non-field names. In C, this 670/// routine will return the translation unit scope, since the 671/// enumeration's scope is a transparent context and structures cannot 672/// contain non-field names. 673Scope *Sema::getNonFieldDeclScope(Scope *S) { 674 while (((S->getFlags() & Scope::DeclScope) == 0) || 675 (S->getEntity() && 676 ((DeclContext *)S->getEntity())->isTransparentContext()) || 677 (S->isClassScope() && !getLangOptions().CPlusPlus)) 678 S = S->getParent(); 679 return S; 680} 681 682void Sema::InitBuiltinVaListType() { 683 if (!Context.getBuiltinVaListType().isNull()) 684 return; 685 686 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 687 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 688 LookupOrdinaryName, ForRedeclaration); 689 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 690 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 691} 692 693/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 694/// file scope. lazily create a decl for it. ForRedeclaration is true 695/// if we're creating this built-in in anticipation of redeclaring the 696/// built-in. 697NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 698 Scope *S, bool ForRedeclaration, 699 SourceLocation Loc) { 700 Builtin::ID BID = (Builtin::ID)bid; 701 702 if (Context.BuiltinInfo.hasVAListUse(BID)) 703 InitBuiltinVaListType(); 704 705 ASTContext::GetBuiltinTypeError Error; 706 QualType R = Context.GetBuiltinType(BID, Error); 707 switch (Error) { 708 case ASTContext::GE_None: 709 // Okay 710 break; 711 712 case ASTContext::GE_Missing_stdio: 713 if (ForRedeclaration) 714 Diag(Loc, diag::err_implicit_decl_requires_stdio) 715 << Context.BuiltinInfo.GetName(BID); 716 return 0; 717 718 case ASTContext::GE_Missing_setjmp: 719 if (ForRedeclaration) 720 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 721 << Context.BuiltinInfo.GetName(BID); 722 return 0; 723 } 724 725 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 726 Diag(Loc, diag::ext_implicit_lib_function_decl) 727 << Context.BuiltinInfo.GetName(BID) 728 << R; 729 if (Context.BuiltinInfo.getHeaderName(BID) && 730 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 731 != Diagnostic::Ignored) 732 Diag(Loc, diag::note_please_include_header) 733 << Context.BuiltinInfo.getHeaderName(BID) 734 << Context.BuiltinInfo.GetName(BID); 735 } 736 737 FunctionDecl *New = FunctionDecl::Create(Context, 738 Context.getTranslationUnitDecl(), 739 Loc, II, R, /*TInfo=*/0, 740 FunctionDecl::Extern, 741 FunctionDecl::None, false, 742 /*hasPrototype=*/true); 743 New->setImplicit(); 744 745 // Create Decl objects for each parameter, adding them to the 746 // FunctionDecl. 747 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 748 llvm::SmallVector<ParmVarDecl*, 16> Params; 749 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 750 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 751 FT->getArgType(i), /*TInfo=*/0, 752 VarDecl::None, VarDecl::None, 0)); 753 New->setParams(Params.data(), Params.size()); 754 } 755 756 AddKnownFunctionAttributes(New); 757 758 // TUScope is the translation-unit scope to insert this function into. 759 // FIXME: This is hideous. We need to teach PushOnScopeChains to 760 // relate Scopes to DeclContexts, and probably eliminate CurContext 761 // entirely, but we're not there yet. 762 DeclContext *SavedContext = CurContext; 763 CurContext = Context.getTranslationUnitDecl(); 764 PushOnScopeChains(New, TUScope); 765 CurContext = SavedContext; 766 return New; 767} 768 769/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 770/// same name and scope as a previous declaration 'Old'. Figure out 771/// how to resolve this situation, merging decls or emitting 772/// diagnostics as appropriate. If there was an error, set New to be invalid. 773/// 774void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 775 // If the new decl is known invalid already, don't bother doing any 776 // merging checks. 777 if (New->isInvalidDecl()) return; 778 779 // Allow multiple definitions for ObjC built-in typedefs. 780 // FIXME: Verify the underlying types are equivalent! 781 if (getLangOptions().ObjC1) { 782 const IdentifierInfo *TypeID = New->getIdentifier(); 783 switch (TypeID->getLength()) { 784 default: break; 785 case 2: 786 if (!TypeID->isStr("id")) 787 break; 788 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 789 // Install the built-in type for 'id', ignoring the current definition. 790 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 791 return; 792 case 5: 793 if (!TypeID->isStr("Class")) 794 break; 795 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 796 // Install the built-in type for 'Class', ignoring the current definition. 797 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 798 return; 799 case 3: 800 if (!TypeID->isStr("SEL")) 801 break; 802 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 803 // Install the built-in type for 'SEL', ignoring the current definition. 804 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 805 return; 806 case 8: 807 if (!TypeID->isStr("Protocol")) 808 break; 809 Context.setObjCProtoType(New->getUnderlyingType()); 810 return; 811 } 812 // Fall through - the typedef name was not a builtin type. 813 } 814 815 // Verify the old decl was also a type. 816 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 817 if (!Old) { 818 Diag(New->getLocation(), diag::err_redefinition_different_kind) 819 << New->getDeclName(); 820 821 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 822 if (OldD->getLocation().isValid()) 823 Diag(OldD->getLocation(), diag::note_previous_definition); 824 825 return New->setInvalidDecl(); 826 } 827 828 // If the old declaration is invalid, just give up here. 829 if (Old->isInvalidDecl()) 830 return New->setInvalidDecl(); 831 832 // Determine the "old" type we'll use for checking and diagnostics. 833 QualType OldType; 834 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 835 OldType = OldTypedef->getUnderlyingType(); 836 else 837 OldType = Context.getTypeDeclType(Old); 838 839 // If the typedef types are not identical, reject them in all languages and 840 // with any extensions enabled. 841 842 if (OldType != New->getUnderlyingType() && 843 Context.getCanonicalType(OldType) != 844 Context.getCanonicalType(New->getUnderlyingType())) { 845 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 846 << New->getUnderlyingType() << OldType; 847 if (Old->getLocation().isValid()) 848 Diag(Old->getLocation(), diag::note_previous_definition); 849 return New->setInvalidDecl(); 850 } 851 852 // The types match. Link up the redeclaration chain if the old 853 // declaration was a typedef. 854 // FIXME: this is a potential source of wierdness if the type 855 // spellings don't match exactly. 856 if (isa<TypedefDecl>(Old)) 857 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 858 859 if (getLangOptions().Microsoft) 860 return; 861 862 if (getLangOptions().CPlusPlus) { 863 // C++ [dcl.typedef]p2: 864 // In a given non-class scope, a typedef specifier can be used to 865 // redefine the name of any type declared in that scope to refer 866 // to the type to which it already refers. 867 if (!isa<CXXRecordDecl>(CurContext)) 868 return; 869 870 // C++0x [dcl.typedef]p4: 871 // In a given class scope, a typedef specifier can be used to redefine 872 // any class-name declared in that scope that is not also a typedef-name 873 // to refer to the type to which it already refers. 874 // 875 // This wording came in via DR424, which was a correction to the 876 // wording in DR56, which accidentally banned code like: 877 // 878 // struct S { 879 // typedef struct A { } A; 880 // }; 881 // 882 // in the C++03 standard. We implement the C++0x semantics, which 883 // allow the above but disallow 884 // 885 // struct S { 886 // typedef int I; 887 // typedef int I; 888 // }; 889 // 890 // since that was the intent of DR56. 891 if (!isa<TypedefDecl >(Old)) 892 return; 893 894 Diag(New->getLocation(), diag::err_redefinition) 895 << New->getDeclName(); 896 Diag(Old->getLocation(), diag::note_previous_definition); 897 return New->setInvalidDecl(); 898 } 899 900 // If we have a redefinition of a typedef in C, emit a warning. This warning 901 // is normally mapped to an error, but can be controlled with 902 // -Wtypedef-redefinition. If either the original or the redefinition is 903 // in a system header, don't emit this for compatibility with GCC. 904 if (getDiagnostics().getSuppressSystemWarnings() && 905 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 906 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 907 return; 908 909 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 910 << New->getDeclName(); 911 Diag(Old->getLocation(), diag::note_previous_definition); 912 return; 913} 914 915/// DeclhasAttr - returns true if decl Declaration already has the target 916/// attribute. 917static bool 918DeclHasAttr(const Decl *decl, const Attr *target) { 919 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 920 if (attr->getKind() == target->getKind()) 921 return true; 922 923 return false; 924} 925 926/// MergeAttributes - append attributes from the Old decl to the New one. 927static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 928 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 929 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 930 Attr *NewAttr = attr->clone(C); 931 NewAttr->setInherited(true); 932 New->addAttr(NewAttr); 933 } 934 } 935} 936 937/// Used in MergeFunctionDecl to keep track of function parameters in 938/// C. 939struct GNUCompatibleParamWarning { 940 ParmVarDecl *OldParm; 941 ParmVarDecl *NewParm; 942 QualType PromotedType; 943}; 944 945 946/// getSpecialMember - get the special member enum for a method. 947Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 948 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 949 if (Ctor->isCopyConstructor()) 950 return Sema::CXXCopyConstructor; 951 952 return Sema::CXXConstructor; 953 } 954 955 if (isa<CXXDestructorDecl>(MD)) 956 return Sema::CXXDestructor; 957 958 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 959 return Sema::CXXCopyAssignment; 960} 961 962/// canRedefineFunction - checks if a function can be redefined. Currently, 963/// only extern inline functions can be redefined, and even then only in 964/// GNU89 mode. 965static bool canRedefineFunction(const FunctionDecl *FD, 966 const LangOptions& LangOpts) { 967 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 968 FD->isInlineSpecified() && 969 FD->getStorageClass() == FunctionDecl::Extern); 970} 971 972/// MergeFunctionDecl - We just parsed a function 'New' from 973/// declarator D which has the same name and scope as a previous 974/// declaration 'Old'. Figure out how to resolve this situation, 975/// merging decls or emitting diagnostics as appropriate. 976/// 977/// In C++, New and Old must be declarations that are not 978/// overloaded. Use IsOverload to determine whether New and Old are 979/// overloaded, and to select the Old declaration that New should be 980/// merged with. 981/// 982/// Returns true if there was an error, false otherwise. 983bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 984 // Verify the old decl was also a function. 985 FunctionDecl *Old = 0; 986 if (FunctionTemplateDecl *OldFunctionTemplate 987 = dyn_cast<FunctionTemplateDecl>(OldD)) 988 Old = OldFunctionTemplate->getTemplatedDecl(); 989 else 990 Old = dyn_cast<FunctionDecl>(OldD); 991 if (!Old) { 992 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 993 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 994 Diag(Shadow->getTargetDecl()->getLocation(), 995 diag::note_using_decl_target); 996 Diag(Shadow->getUsingDecl()->getLocation(), 997 diag::note_using_decl) << 0; 998 return true; 999 } 1000 1001 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1002 << New->getDeclName(); 1003 Diag(OldD->getLocation(), diag::note_previous_definition); 1004 return true; 1005 } 1006 1007 // Determine whether the previous declaration was a definition, 1008 // implicit declaration, or a declaration. 1009 diag::kind PrevDiag; 1010 if (Old->isThisDeclarationADefinition()) 1011 PrevDiag = diag::note_previous_definition; 1012 else if (Old->isImplicit()) 1013 PrevDiag = diag::note_previous_implicit_declaration; 1014 else 1015 PrevDiag = diag::note_previous_declaration; 1016 1017 QualType OldQType = Context.getCanonicalType(Old->getType()); 1018 QualType NewQType = Context.getCanonicalType(New->getType()); 1019 1020 // Don't complain about this if we're in GNU89 mode and the old function 1021 // is an extern inline function. 1022 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1023 New->getStorageClass() == FunctionDecl::Static && 1024 Old->getStorageClass() != FunctionDecl::Static && 1025 !canRedefineFunction(Old, getLangOptions())) { 1026 Diag(New->getLocation(), diag::err_static_non_static) 1027 << New; 1028 Diag(Old->getLocation(), PrevDiag); 1029 return true; 1030 } 1031 1032 // If a function is first declared with a calling convention, but is 1033 // later declared or defined without one, the second decl assumes the 1034 // calling convention of the first. 1035 // 1036 // For the new decl, we have to look at the NON-canonical type to tell the 1037 // difference between a function that really doesn't have a calling 1038 // convention and one that is declared cdecl. That's because in 1039 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1040 // because it is the default calling convention. 1041 // 1042 // Note also that we DO NOT return at this point, because we still have 1043 // other tests to run. 1044 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1045 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1046 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1047 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1048 if (OldTypeInfo.getCC() != CC_Default && 1049 NewTypeInfo.getCC() == CC_Default) { 1050 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1051 New->setType(NewQType); 1052 NewQType = Context.getCanonicalType(NewQType); 1053 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1054 NewTypeInfo.getCC())) { 1055 // Calling conventions really aren't compatible, so complain. 1056 Diag(New->getLocation(), diag::err_cconv_change) 1057 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1058 << (OldTypeInfo.getCC() == CC_Default) 1059 << (OldTypeInfo.getCC() == CC_Default ? "" : 1060 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1061 Diag(Old->getLocation(), diag::note_previous_declaration); 1062 return true; 1063 } 1064 1065 // FIXME: diagnose the other way around? 1066 if (OldType->getNoReturnAttr() && 1067 !NewType->getNoReturnAttr()) { 1068 NewQType = Context.getNoReturnType(NewQType); 1069 New->setType(NewQType); 1070 assert(NewQType.isCanonical()); 1071 } 1072 1073 if (getLangOptions().CPlusPlus) { 1074 // (C++98 13.1p2): 1075 // Certain function declarations cannot be overloaded: 1076 // -- Function declarations that differ only in the return type 1077 // cannot be overloaded. 1078 QualType OldReturnType 1079 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1080 QualType NewReturnType 1081 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1082 QualType ResQT; 1083 if (OldReturnType != NewReturnType) { 1084 if (NewReturnType->isObjCObjectPointerType() 1085 && OldReturnType->isObjCObjectPointerType()) 1086 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1087 if (ResQT.isNull()) { 1088 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1089 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1090 return true; 1091 } 1092 else 1093 NewQType = ResQT; 1094 } 1095 1096 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1097 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1098 if (OldMethod && NewMethod) { 1099 // Preserve triviality. 1100 NewMethod->setTrivial(OldMethod->isTrivial()); 1101 1102 bool isFriend = NewMethod->getFriendObjectKind(); 1103 1104 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1105 // -- Member function declarations with the same name and the 1106 // same parameter types cannot be overloaded if any of them 1107 // is a static member function declaration. 1108 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1109 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1110 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1111 return true; 1112 } 1113 1114 // C++ [class.mem]p1: 1115 // [...] A member shall not be declared twice in the 1116 // member-specification, except that a nested class or member 1117 // class template can be declared and then later defined. 1118 unsigned NewDiag; 1119 if (isa<CXXConstructorDecl>(OldMethod)) 1120 NewDiag = diag::err_constructor_redeclared; 1121 else if (isa<CXXDestructorDecl>(NewMethod)) 1122 NewDiag = diag::err_destructor_redeclared; 1123 else if (isa<CXXConversionDecl>(NewMethod)) 1124 NewDiag = diag::err_conv_function_redeclared; 1125 else 1126 NewDiag = diag::err_member_redeclared; 1127 1128 Diag(New->getLocation(), NewDiag); 1129 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1130 1131 // Complain if this is an explicit declaration of a special 1132 // member that was initially declared implicitly. 1133 // 1134 // As an exception, it's okay to befriend such methods in order 1135 // to permit the implicit constructor/destructor/operator calls. 1136 } else if (OldMethod->isImplicit()) { 1137 if (isFriend) { 1138 NewMethod->setImplicit(); 1139 } else { 1140 Diag(NewMethod->getLocation(), 1141 diag::err_definition_of_implicitly_declared_member) 1142 << New << getSpecialMember(OldMethod); 1143 return true; 1144 } 1145 } 1146 } 1147 1148 // (C++98 8.3.5p3): 1149 // All declarations for a function shall agree exactly in both the 1150 // return type and the parameter-type-list. 1151 // attributes should be ignored when comparing. 1152 if (Context.getNoReturnType(OldQType, false) == 1153 Context.getNoReturnType(NewQType, false)) 1154 return MergeCompatibleFunctionDecls(New, Old); 1155 1156 // Fall through for conflicting redeclarations and redefinitions. 1157 } 1158 1159 // C: Function types need to be compatible, not identical. This handles 1160 // duplicate function decls like "void f(int); void f(enum X);" properly. 1161 if (!getLangOptions().CPlusPlus && 1162 Context.typesAreCompatible(OldQType, NewQType)) { 1163 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1164 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1165 const FunctionProtoType *OldProto = 0; 1166 if (isa<FunctionNoProtoType>(NewFuncType) && 1167 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1168 // The old declaration provided a function prototype, but the 1169 // new declaration does not. Merge in the prototype. 1170 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1171 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1172 OldProto->arg_type_end()); 1173 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1174 ParamTypes.data(), ParamTypes.size(), 1175 OldProto->isVariadic(), 1176 OldProto->getTypeQuals(), 1177 false, false, 0, 0, 1178 OldProto->getExtInfo()); 1179 New->setType(NewQType); 1180 New->setHasInheritedPrototype(); 1181 1182 // Synthesize a parameter for each argument type. 1183 llvm::SmallVector<ParmVarDecl*, 16> Params; 1184 for (FunctionProtoType::arg_type_iterator 1185 ParamType = OldProto->arg_type_begin(), 1186 ParamEnd = OldProto->arg_type_end(); 1187 ParamType != ParamEnd; ++ParamType) { 1188 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1189 SourceLocation(), 0, 1190 *ParamType, /*TInfo=*/0, 1191 VarDecl::None, VarDecl::None, 1192 0); 1193 Param->setImplicit(); 1194 Params.push_back(Param); 1195 } 1196 1197 New->setParams(Params.data(), Params.size()); 1198 } 1199 1200 return MergeCompatibleFunctionDecls(New, Old); 1201 } 1202 1203 // GNU C permits a K&R definition to follow a prototype declaration 1204 // if the declared types of the parameters in the K&R definition 1205 // match the types in the prototype declaration, even when the 1206 // promoted types of the parameters from the K&R definition differ 1207 // from the types in the prototype. GCC then keeps the types from 1208 // the prototype. 1209 // 1210 // If a variadic prototype is followed by a non-variadic K&R definition, 1211 // the K&R definition becomes variadic. This is sort of an edge case, but 1212 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1213 // C99 6.9.1p8. 1214 if (!getLangOptions().CPlusPlus && 1215 Old->hasPrototype() && !New->hasPrototype() && 1216 New->getType()->getAs<FunctionProtoType>() && 1217 Old->getNumParams() == New->getNumParams()) { 1218 llvm::SmallVector<QualType, 16> ArgTypes; 1219 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1220 const FunctionProtoType *OldProto 1221 = Old->getType()->getAs<FunctionProtoType>(); 1222 const FunctionProtoType *NewProto 1223 = New->getType()->getAs<FunctionProtoType>(); 1224 1225 // Determine whether this is the GNU C extension. 1226 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1227 NewProto->getResultType()); 1228 bool LooseCompatible = !MergedReturn.isNull(); 1229 for (unsigned Idx = 0, End = Old->getNumParams(); 1230 LooseCompatible && Idx != End; ++Idx) { 1231 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1232 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1233 if (Context.typesAreCompatible(OldParm->getType(), 1234 NewProto->getArgType(Idx))) { 1235 ArgTypes.push_back(NewParm->getType()); 1236 } else if (Context.typesAreCompatible(OldParm->getType(), 1237 NewParm->getType())) { 1238 GNUCompatibleParamWarning Warn 1239 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1240 Warnings.push_back(Warn); 1241 ArgTypes.push_back(NewParm->getType()); 1242 } else 1243 LooseCompatible = false; 1244 } 1245 1246 if (LooseCompatible) { 1247 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1248 Diag(Warnings[Warn].NewParm->getLocation(), 1249 diag::ext_param_promoted_not_compatible_with_prototype) 1250 << Warnings[Warn].PromotedType 1251 << Warnings[Warn].OldParm->getType(); 1252 Diag(Warnings[Warn].OldParm->getLocation(), 1253 diag::note_previous_declaration); 1254 } 1255 1256 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1257 ArgTypes.size(), 1258 OldProto->isVariadic(), 0, 1259 false, false, 0, 0, 1260 OldProto->getExtInfo())); 1261 return MergeCompatibleFunctionDecls(New, Old); 1262 } 1263 1264 // Fall through to diagnose conflicting types. 1265 } 1266 1267 // A function that has already been declared has been redeclared or defined 1268 // with a different type- show appropriate diagnostic 1269 if (unsigned BuiltinID = Old->getBuiltinID()) { 1270 // The user has declared a builtin function with an incompatible 1271 // signature. 1272 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1273 // The function the user is redeclaring is a library-defined 1274 // function like 'malloc' or 'printf'. Warn about the 1275 // redeclaration, then pretend that we don't know about this 1276 // library built-in. 1277 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1278 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1279 << Old << Old->getType(); 1280 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1281 Old->setInvalidDecl(); 1282 return false; 1283 } 1284 1285 PrevDiag = diag::note_previous_builtin_declaration; 1286 } 1287 1288 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1289 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1290 return true; 1291} 1292 1293/// \brief Completes the merge of two function declarations that are 1294/// known to be compatible. 1295/// 1296/// This routine handles the merging of attributes and other 1297/// properties of function declarations form the old declaration to 1298/// the new declaration, once we know that New is in fact a 1299/// redeclaration of Old. 1300/// 1301/// \returns false 1302bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1303 // Merge the attributes 1304 MergeAttributes(New, Old, Context); 1305 1306 // Merge the storage class. 1307 if (Old->getStorageClass() != FunctionDecl::Extern && 1308 Old->getStorageClass() != FunctionDecl::None) 1309 New->setStorageClass(Old->getStorageClass()); 1310 1311 // Merge "pure" flag. 1312 if (Old->isPure()) 1313 New->setPure(); 1314 1315 // Merge the "deleted" flag. 1316 if (Old->isDeleted()) 1317 New->setDeleted(); 1318 1319 if (getLangOptions().CPlusPlus) 1320 return MergeCXXFunctionDecl(New, Old); 1321 1322 return false; 1323} 1324 1325/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1326/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1327/// situation, merging decls or emitting diagnostics as appropriate. 1328/// 1329/// Tentative definition rules (C99 6.9.2p2) are checked by 1330/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1331/// definitions here, since the initializer hasn't been attached. 1332/// 1333void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1334 // If the new decl is already invalid, don't do any other checking. 1335 if (New->isInvalidDecl()) 1336 return; 1337 1338 // Verify the old decl was also a variable. 1339 VarDecl *Old = 0; 1340 if (!Previous.isSingleResult() || 1341 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1342 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1343 << New->getDeclName(); 1344 Diag(Previous.getRepresentativeDecl()->getLocation(), 1345 diag::note_previous_definition); 1346 return New->setInvalidDecl(); 1347 } 1348 1349 MergeAttributes(New, Old, Context); 1350 1351 // Merge the types 1352 QualType MergedT; 1353 if (getLangOptions().CPlusPlus) { 1354 if (Context.hasSameType(New->getType(), Old->getType())) 1355 MergedT = New->getType(); 1356 // C++ [basic.link]p10: 1357 // [...] the types specified by all declarations referring to a given 1358 // object or function shall be identical, except that declarations for an 1359 // array object can specify array types that differ by the presence or 1360 // absence of a major array bound (8.3.4). 1361 else if (Old->getType()->isIncompleteArrayType() && 1362 New->getType()->isArrayType()) { 1363 CanQual<ArrayType> OldArray 1364 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1365 CanQual<ArrayType> NewArray 1366 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1367 if (OldArray->getElementType() == NewArray->getElementType()) 1368 MergedT = New->getType(); 1369 } else if (Old->getType()->isArrayType() && 1370 New->getType()->isIncompleteArrayType()) { 1371 CanQual<ArrayType> OldArray 1372 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1373 CanQual<ArrayType> NewArray 1374 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1375 if (OldArray->getElementType() == NewArray->getElementType()) 1376 MergedT = Old->getType(); 1377 } else if (New->getType()->isObjCObjectPointerType() 1378 && Old->getType()->isObjCObjectPointerType()) { 1379 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1380 } 1381 } else { 1382 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1383 } 1384 if (MergedT.isNull()) { 1385 Diag(New->getLocation(), diag::err_redefinition_different_type) 1386 << New->getDeclName(); 1387 Diag(Old->getLocation(), diag::note_previous_definition); 1388 return New->setInvalidDecl(); 1389 } 1390 New->setType(MergedT); 1391 1392 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1393 if (New->getStorageClass() == VarDecl::Static && 1394 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1395 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1396 Diag(Old->getLocation(), diag::note_previous_definition); 1397 return New->setInvalidDecl(); 1398 } 1399 // C99 6.2.2p4: 1400 // For an identifier declared with the storage-class specifier 1401 // extern in a scope in which a prior declaration of that 1402 // identifier is visible,23) if the prior declaration specifies 1403 // internal or external linkage, the linkage of the identifier at 1404 // the later declaration is the same as the linkage specified at 1405 // the prior declaration. If no prior declaration is visible, or 1406 // if the prior declaration specifies no linkage, then the 1407 // identifier has external linkage. 1408 if (New->hasExternalStorage() && Old->hasLinkage()) 1409 /* Okay */; 1410 else if (New->getStorageClass() != VarDecl::Static && 1411 Old->getStorageClass() == VarDecl::Static) { 1412 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1413 Diag(Old->getLocation(), diag::note_previous_definition); 1414 return New->setInvalidDecl(); 1415 } 1416 1417 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1418 1419 // FIXME: The test for external storage here seems wrong? We still 1420 // need to check for mismatches. 1421 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1422 // Don't complain about out-of-line definitions of static members. 1423 !(Old->getLexicalDeclContext()->isRecord() && 1424 !New->getLexicalDeclContext()->isRecord())) { 1425 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1426 Diag(Old->getLocation(), diag::note_previous_definition); 1427 return New->setInvalidDecl(); 1428 } 1429 1430 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1431 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1432 Diag(Old->getLocation(), diag::note_previous_definition); 1433 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1434 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1435 Diag(Old->getLocation(), diag::note_previous_definition); 1436 } 1437 1438 // C++ doesn't have tentative definitions, so go right ahead and check here. 1439 const VarDecl *Def; 1440 if (getLangOptions().CPlusPlus && 1441 New->isThisDeclarationADefinition() == VarDecl::Definition && 1442 (Def = Old->getDefinition())) { 1443 Diag(New->getLocation(), diag::err_redefinition) 1444 << New->getDeclName(); 1445 Diag(Def->getLocation(), diag::note_previous_definition); 1446 New->setInvalidDecl(); 1447 return; 1448 } 1449 1450 // Keep a chain of previous declarations. 1451 New->setPreviousDeclaration(Old); 1452 1453 // Inherit access appropriately. 1454 New->setAccess(Old->getAccess()); 1455} 1456 1457/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1458/// no declarator (e.g. "struct foo;") is parsed. 1459Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1460 DeclSpec &DS) { 1461 // FIXME: Error on auto/register at file scope 1462 // FIXME: Error on inline/virtual/explicit 1463 // FIXME: Warn on useless __thread 1464 // FIXME: Warn on useless const/volatile 1465 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1466 // FIXME: Warn on useless attributes 1467 Decl *TagD = 0; 1468 TagDecl *Tag = 0; 1469 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1470 DS.getTypeSpecType() == DeclSpec::TST_struct || 1471 DS.getTypeSpecType() == DeclSpec::TST_union || 1472 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1473 TagD = static_cast<Decl *>(DS.getTypeRep()); 1474 1475 if (!TagD) // We probably had an error 1476 return DeclPtrTy(); 1477 1478 // Note that the above type specs guarantee that the 1479 // type rep is a Decl, whereas in many of the others 1480 // it's a Type. 1481 Tag = dyn_cast<TagDecl>(TagD); 1482 } 1483 1484 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1485 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1486 // or incomplete types shall not be restrict-qualified." 1487 if (TypeQuals & DeclSpec::TQ_restrict) 1488 Diag(DS.getRestrictSpecLoc(), 1489 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1490 << DS.getSourceRange(); 1491 } 1492 1493 if (DS.isFriendSpecified()) { 1494 // If we're dealing with a class template decl, assume that the 1495 // template routines are handling it. 1496 if (TagD && isa<ClassTemplateDecl>(TagD)) 1497 return DeclPtrTy(); 1498 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1499 } 1500 1501 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1502 // If there are attributes in the DeclSpec, apply them to the record. 1503 if (const AttributeList *AL = DS.getAttributes()) 1504 ProcessDeclAttributeList(S, Record, AL); 1505 1506 if (!Record->getDeclName() && Record->isDefinition() && 1507 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1508 if (getLangOptions().CPlusPlus || 1509 Record->getDeclContext()->isRecord()) 1510 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1511 1512 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1513 << DS.getSourceRange(); 1514 } 1515 1516 // Microsoft allows unnamed struct/union fields. Don't complain 1517 // about them. 1518 // FIXME: Should we support Microsoft's extensions in this area? 1519 if (Record->getDeclName() && getLangOptions().Microsoft) 1520 return DeclPtrTy::make(Tag); 1521 } 1522 1523 if (!DS.isMissingDeclaratorOk() && 1524 DS.getTypeSpecType() != DeclSpec::TST_error) { 1525 // Warn about typedefs of enums without names, since this is an 1526 // extension in both Microsoft an GNU. 1527 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1528 Tag && isa<EnumDecl>(Tag)) { 1529 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1530 << DS.getSourceRange(); 1531 return DeclPtrTy::make(Tag); 1532 } 1533 1534 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1535 << DS.getSourceRange(); 1536 } 1537 1538 return DeclPtrTy::make(Tag); 1539} 1540 1541/// We are trying to inject an anonymous member into the given scope; 1542/// check if there's an existing declaration that can't be overloaded. 1543/// 1544/// \return true if this is a forbidden redeclaration 1545static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1546 Scope *S, 1547 DeclContext *Owner, 1548 DeclarationName Name, 1549 SourceLocation NameLoc, 1550 unsigned diagnostic) { 1551 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1552 Sema::ForRedeclaration); 1553 if (!SemaRef.LookupName(R, S)) return false; 1554 1555 if (R.getAsSingle<TagDecl>()) 1556 return false; 1557 1558 // Pick a representative declaration. 1559 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1560 if (PrevDecl && Owner->isRecord()) { 1561 RecordDecl *Record = cast<RecordDecl>(Owner); 1562 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1563 return false; 1564 } 1565 1566 SemaRef.Diag(NameLoc, diagnostic) << Name; 1567 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1568 1569 return true; 1570} 1571 1572/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1573/// anonymous struct or union AnonRecord into the owning context Owner 1574/// and scope S. This routine will be invoked just after we realize 1575/// that an unnamed union or struct is actually an anonymous union or 1576/// struct, e.g., 1577/// 1578/// @code 1579/// union { 1580/// int i; 1581/// float f; 1582/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1583/// // f into the surrounding scope.x 1584/// @endcode 1585/// 1586/// This routine is recursive, injecting the names of nested anonymous 1587/// structs/unions into the owning context and scope as well. 1588static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1589 DeclContext *Owner, 1590 RecordDecl *AnonRecord, 1591 AccessSpecifier AS) { 1592 unsigned diagKind 1593 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1594 : diag::err_anonymous_struct_member_redecl; 1595 1596 bool Invalid = false; 1597 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1598 FEnd = AnonRecord->field_end(); 1599 F != FEnd; ++F) { 1600 if ((*F)->getDeclName()) { 1601 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1602 (*F)->getLocation(), diagKind)) { 1603 // C++ [class.union]p2: 1604 // The names of the members of an anonymous union shall be 1605 // distinct from the names of any other entity in the 1606 // scope in which the anonymous union is declared. 1607 Invalid = true; 1608 } else { 1609 // C++ [class.union]p2: 1610 // For the purpose of name lookup, after the anonymous union 1611 // definition, the members of the anonymous union are 1612 // considered to have been defined in the scope in which the 1613 // anonymous union is declared. 1614 Owner->makeDeclVisibleInContext(*F); 1615 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1616 SemaRef.IdResolver.AddDecl(*F); 1617 1618 // That includes picking up the appropriate access specifier. 1619 if (AS != AS_none) (*F)->setAccess(AS); 1620 } 1621 } else if (const RecordType *InnerRecordType 1622 = (*F)->getType()->getAs<RecordType>()) { 1623 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1624 if (InnerRecord->isAnonymousStructOrUnion()) 1625 Invalid = Invalid || 1626 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1627 InnerRecord, AS); 1628 } 1629 } 1630 1631 return Invalid; 1632} 1633 1634/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1635/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1636/// illegal input values are mapped to VarDecl::None. 1637/// If the input declaration context is a linkage specification 1638/// with no braces, then Extern is mapped to None. 1639static VarDecl::StorageClass 1640StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1641 DeclContext *DC) { 1642 switch (StorageClassSpec) { 1643 case DeclSpec::SCS_unspecified: return VarDecl::None; 1644 case DeclSpec::SCS_extern: 1645 // If the current context is a C++ linkage specification 1646 // having no braces, then the keyword "extern" is properly part 1647 // of the linkage specification itself, rather than being 1648 // the written storage class specifier. 1649 return (DC && isa<LinkageSpecDecl>(DC) && 1650 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1651 ? VarDecl::None : VarDecl::Extern; 1652 case DeclSpec::SCS_static: return VarDecl::Static; 1653 case DeclSpec::SCS_auto: return VarDecl::Auto; 1654 case DeclSpec::SCS_register: return VarDecl::Register; 1655 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1656 // Illegal SCSs map to None: error reporting is up to the caller. 1657 case DeclSpec::SCS_mutable: // Fall through. 1658 case DeclSpec::SCS_typedef: return VarDecl::None; 1659 } 1660 llvm_unreachable("unknown storage class specifier"); 1661} 1662 1663/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1664/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1665/// illegal input values are mapped to FunctionDecl::None. 1666/// If the input declaration context is a linkage specification 1667/// with no braces, then Extern is mapped to None. 1668static FunctionDecl::StorageClass 1669StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1670 DeclContext *DC) { 1671 switch (StorageClassSpec) { 1672 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1673 case DeclSpec::SCS_extern: 1674 // If the current context is a C++ linkage specification 1675 // having no braces, then the keyword "extern" is properly part 1676 // of the linkage specification itself, rather than being 1677 // the written storage class specifier. 1678 return (DC && isa<LinkageSpecDecl>(DC) && 1679 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1680 ? FunctionDecl::None : FunctionDecl::Extern; 1681 case DeclSpec::SCS_static: return FunctionDecl::Static; 1682 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1683 // Illegal SCSs map to None: error reporting is up to the caller. 1684 case DeclSpec::SCS_auto: // Fall through. 1685 case DeclSpec::SCS_mutable: // Fall through. 1686 case DeclSpec::SCS_register: // Fall through. 1687 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1688 } 1689 llvm_unreachable("unknown storage class specifier"); 1690} 1691 1692/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1693/// anonymous structure or union. Anonymous unions are a C++ feature 1694/// (C++ [class.union]) and a GNU C extension; anonymous structures 1695/// are a GNU C and GNU C++ extension. 1696Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1697 AccessSpecifier AS, 1698 RecordDecl *Record) { 1699 DeclContext *Owner = Record->getDeclContext(); 1700 1701 // Diagnose whether this anonymous struct/union is an extension. 1702 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1703 Diag(Record->getLocation(), diag::ext_anonymous_union); 1704 else if (!Record->isUnion()) 1705 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1706 1707 // C and C++ require different kinds of checks for anonymous 1708 // structs/unions. 1709 bool Invalid = false; 1710 if (getLangOptions().CPlusPlus) { 1711 const char* PrevSpec = 0; 1712 unsigned DiagID; 1713 // C++ [class.union]p3: 1714 // Anonymous unions declared in a named namespace or in the 1715 // global namespace shall be declared static. 1716 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1717 (isa<TranslationUnitDecl>(Owner) || 1718 (isa<NamespaceDecl>(Owner) && 1719 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1720 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1721 Invalid = true; 1722 1723 // Recover by adding 'static'. 1724 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1725 PrevSpec, DiagID); 1726 } 1727 // C++ [class.union]p3: 1728 // A storage class is not allowed in a declaration of an 1729 // anonymous union in a class scope. 1730 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1731 isa<RecordDecl>(Owner)) { 1732 Diag(DS.getStorageClassSpecLoc(), 1733 diag::err_anonymous_union_with_storage_spec); 1734 Invalid = true; 1735 1736 // Recover by removing the storage specifier. 1737 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1738 PrevSpec, DiagID); 1739 } 1740 1741 // C++ [class.union]p2: 1742 // The member-specification of an anonymous union shall only 1743 // define non-static data members. [Note: nested types and 1744 // functions cannot be declared within an anonymous union. ] 1745 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1746 MemEnd = Record->decls_end(); 1747 Mem != MemEnd; ++Mem) { 1748 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1749 // C++ [class.union]p3: 1750 // An anonymous union shall not have private or protected 1751 // members (clause 11). 1752 assert(FD->getAccess() != AS_none); 1753 if (FD->getAccess() != AS_public) { 1754 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1755 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1756 Invalid = true; 1757 } 1758 } else if ((*Mem)->isImplicit()) { 1759 // Any implicit members are fine. 1760 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1761 // This is a type that showed up in an 1762 // elaborated-type-specifier inside the anonymous struct or 1763 // union, but which actually declares a type outside of the 1764 // anonymous struct or union. It's okay. 1765 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1766 if (!MemRecord->isAnonymousStructOrUnion() && 1767 MemRecord->getDeclName()) { 1768 // This is a nested type declaration. 1769 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1770 << (int)Record->isUnion(); 1771 Invalid = true; 1772 } 1773 } else if (isa<AccessSpecDecl>(*Mem)) { 1774 // Any access specifier is fine. 1775 } else { 1776 // We have something that isn't a non-static data 1777 // member. Complain about it. 1778 unsigned DK = diag::err_anonymous_record_bad_member; 1779 if (isa<TypeDecl>(*Mem)) 1780 DK = diag::err_anonymous_record_with_type; 1781 else if (isa<FunctionDecl>(*Mem)) 1782 DK = diag::err_anonymous_record_with_function; 1783 else if (isa<VarDecl>(*Mem)) 1784 DK = diag::err_anonymous_record_with_static; 1785 Diag((*Mem)->getLocation(), DK) 1786 << (int)Record->isUnion(); 1787 Invalid = true; 1788 } 1789 } 1790 } 1791 1792 if (!Record->isUnion() && !Owner->isRecord()) { 1793 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1794 << (int)getLangOptions().CPlusPlus; 1795 Invalid = true; 1796 } 1797 1798 // Mock up a declarator. 1799 Declarator Dc(DS, Declarator::TypeNameContext); 1800 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1801 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1802 1803 // Create a declaration for this anonymous struct/union. 1804 NamedDecl *Anon = 0; 1805 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1806 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1807 /*IdentifierInfo=*/0, 1808 Context.getTypeDeclType(Record), 1809 TInfo, 1810 /*BitWidth=*/0, /*Mutable=*/false); 1811 Anon->setAccess(AS); 1812 if (getLangOptions().CPlusPlus) { 1813 FieldCollector->Add(cast<FieldDecl>(Anon)); 1814 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1815 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1816 } 1817 } else { 1818 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1819 assert(SCSpec != DeclSpec::SCS_typedef && 1820 "Parser allowed 'typedef' as storage class VarDecl."); 1821 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1822 if (SCSpec == DeclSpec::SCS_mutable) { 1823 // mutable can only appear on non-static class members, so it's always 1824 // an error here 1825 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1826 Invalid = true; 1827 SC = VarDecl::None; 1828 } 1829 SCSpec = DS.getStorageClassSpecAsWritten(); 1830 VarDecl::StorageClass SCAsWritten 1831 = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1832 1833 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1834 /*IdentifierInfo=*/0, 1835 Context.getTypeDeclType(Record), 1836 TInfo, SC, SCAsWritten); 1837 } 1838 Anon->setImplicit(); 1839 1840 // Add the anonymous struct/union object to the current 1841 // context. We'll be referencing this object when we refer to one of 1842 // its members. 1843 Owner->addDecl(Anon); 1844 1845 // Inject the members of the anonymous struct/union into the owning 1846 // context and into the identifier resolver chain for name lookup 1847 // purposes. 1848 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1849 Invalid = true; 1850 1851 // Mark this as an anonymous struct/union type. Note that we do not 1852 // do this until after we have already checked and injected the 1853 // members of this anonymous struct/union type, because otherwise 1854 // the members could be injected twice: once by DeclContext when it 1855 // builds its lookup table, and once by 1856 // InjectAnonymousStructOrUnionMembers. 1857 Record->setAnonymousStructOrUnion(true); 1858 1859 if (Invalid) 1860 Anon->setInvalidDecl(); 1861 1862 return DeclPtrTy::make(Anon); 1863} 1864 1865 1866/// GetNameForDeclarator - Determine the full declaration name for the 1867/// given Declarator. 1868DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1869 return GetNameFromUnqualifiedId(D.getName()); 1870} 1871 1872/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1873DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1874 switch (Name.getKind()) { 1875 case UnqualifiedId::IK_Identifier: 1876 return DeclarationName(Name.Identifier); 1877 1878 case UnqualifiedId::IK_OperatorFunctionId: 1879 return Context.DeclarationNames.getCXXOperatorName( 1880 Name.OperatorFunctionId.Operator); 1881 1882 case UnqualifiedId::IK_LiteralOperatorId: 1883 return Context.DeclarationNames.getCXXLiteralOperatorName( 1884 Name.Identifier); 1885 1886 case UnqualifiedId::IK_ConversionFunctionId: { 1887 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1888 if (Ty.isNull()) 1889 return DeclarationName(); 1890 1891 return Context.DeclarationNames.getCXXConversionFunctionName( 1892 Context.getCanonicalType(Ty)); 1893 } 1894 1895 case UnqualifiedId::IK_ConstructorName: { 1896 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1897 if (Ty.isNull()) 1898 return DeclarationName(); 1899 1900 return Context.DeclarationNames.getCXXConstructorName( 1901 Context.getCanonicalType(Ty)); 1902 } 1903 1904 case UnqualifiedId::IK_ConstructorTemplateId: { 1905 // In well-formed code, we can only have a constructor 1906 // template-id that refers to the current context, so go there 1907 // to find the actual type being constructed. 1908 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1909 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1910 return DeclarationName(); 1911 1912 // Determine the type of the class being constructed. 1913 QualType CurClassType = Context.getTypeDeclType(CurClass); 1914 1915 // FIXME: Check two things: that the template-id names the same type as 1916 // CurClassType, and that the template-id does not occur when the name 1917 // was qualified. 1918 1919 return Context.DeclarationNames.getCXXConstructorName( 1920 Context.getCanonicalType(CurClassType)); 1921 } 1922 1923 case UnqualifiedId::IK_DestructorName: { 1924 QualType Ty = GetTypeFromParser(Name.DestructorName); 1925 if (Ty.isNull()) 1926 return DeclarationName(); 1927 1928 return Context.DeclarationNames.getCXXDestructorName( 1929 Context.getCanonicalType(Ty)); 1930 } 1931 1932 case UnqualifiedId::IK_TemplateId: { 1933 TemplateName TName 1934 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1935 return Context.getNameForTemplate(TName); 1936 } 1937 } 1938 1939 assert(false && "Unknown name kind"); 1940 return DeclarationName(); 1941} 1942 1943/// isNearlyMatchingFunction - Determine whether the C++ functions 1944/// Declaration and Definition are "nearly" matching. This heuristic 1945/// is used to improve diagnostics in the case where an out-of-line 1946/// function definition doesn't match any declaration within 1947/// the class or namespace. 1948static bool isNearlyMatchingFunction(ASTContext &Context, 1949 FunctionDecl *Declaration, 1950 FunctionDecl *Definition) { 1951 if (Declaration->param_size() != Definition->param_size()) 1952 return false; 1953 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1954 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1955 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1956 1957 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1958 DefParamTy.getNonReferenceType())) 1959 return false; 1960 } 1961 1962 return true; 1963} 1964 1965/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 1966/// declarator needs to be rebuilt in the current instantiation. 1967/// Any bits of declarator which appear before the name are valid for 1968/// consideration here. That's specifically the type in the decl spec 1969/// and the base type in any member-pointer chunks. 1970static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 1971 DeclarationName Name) { 1972 // The types we specifically need to rebuild are: 1973 // - typenames, typeofs, and decltypes 1974 // - types which will become injected class names 1975 // Of course, we also need to rebuild any type referencing such a 1976 // type. It's safest to just say "dependent", but we call out a 1977 // few cases here. 1978 1979 DeclSpec &DS = D.getMutableDeclSpec(); 1980 switch (DS.getTypeSpecType()) { 1981 case DeclSpec::TST_typename: 1982 case DeclSpec::TST_typeofType: 1983 case DeclSpec::TST_typeofExpr: 1984 case DeclSpec::TST_decltype: { 1985 // Grab the type from the parser. 1986 TypeSourceInfo *TSI = 0; 1987 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 1988 if (T.isNull() || !T->isDependentType()) break; 1989 1990 // Make sure there's a type source info. This isn't really much 1991 // of a waste; most dependent types should have type source info 1992 // attached already. 1993 if (!TSI) 1994 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 1995 1996 // Rebuild the type in the current instantiation. 1997 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 1998 if (!TSI) return true; 1999 2000 // Store the new type back in the decl spec. 2001 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2002 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2003 break; 2004 } 2005 2006 default: 2007 // Nothing to do for these decl specs. 2008 break; 2009 } 2010 2011 // It doesn't matter what order we do this in. 2012 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2013 DeclaratorChunk &Chunk = D.getTypeObject(I); 2014 2015 // The only type information in the declarator which can come 2016 // before the declaration name is the base type of a member 2017 // pointer. 2018 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2019 continue; 2020 2021 // Rebuild the scope specifier in-place. 2022 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2023 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2024 return true; 2025 } 2026 2027 return false; 2028} 2029 2030Sema::DeclPtrTy 2031Sema::HandleDeclarator(Scope *S, Declarator &D, 2032 MultiTemplateParamsArg TemplateParamLists, 2033 bool IsFunctionDefinition) { 2034 DeclarationName Name = GetNameForDeclarator(D); 2035 2036 // All of these full declarators require an identifier. If it doesn't have 2037 // one, the ParsedFreeStandingDeclSpec action should be used. 2038 if (!Name) { 2039 if (!D.isInvalidType()) // Reject this if we think it is valid. 2040 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2041 diag::err_declarator_need_ident) 2042 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2043 return DeclPtrTy(); 2044 } 2045 2046 // The scope passed in may not be a decl scope. Zip up the scope tree until 2047 // we find one that is. 2048 while ((S->getFlags() & Scope::DeclScope) == 0 || 2049 (S->getFlags() & Scope::TemplateParamScope) != 0) 2050 S = S->getParent(); 2051 2052 DeclContext *DC = CurContext; 2053 if (D.getCXXScopeSpec().isInvalid()) 2054 D.setInvalidType(); 2055 else if (D.getCXXScopeSpec().isSet()) { 2056 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2057 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2058 if (!DC) { 2059 // If we could not compute the declaration context, it's because the 2060 // declaration context is dependent but does not refer to a class, 2061 // class template, or class template partial specialization. Complain 2062 // and return early, to avoid the coming semantic disaster. 2063 Diag(D.getIdentifierLoc(), 2064 diag::err_template_qualified_declarator_no_match) 2065 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2066 << D.getCXXScopeSpec().getRange(); 2067 return DeclPtrTy(); 2068 } 2069 2070 bool IsDependentContext = DC->isDependentContext(); 2071 2072 if (!IsDependentContext && 2073 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2074 return DeclPtrTy(); 2075 2076 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2077 Diag(D.getIdentifierLoc(), 2078 diag::err_member_def_undefined_record) 2079 << Name << DC << D.getCXXScopeSpec().getRange(); 2080 D.setInvalidType(); 2081 } 2082 2083 // Check whether we need to rebuild the type of the given 2084 // declaration in the current instantiation. 2085 if (EnteringContext && IsDependentContext && 2086 TemplateParamLists.size() != 0) { 2087 ContextRAII SavedContext(*this, DC); 2088 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2089 D.setInvalidType(); 2090 } 2091 } 2092 2093 NamedDecl *New; 2094 2095 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2096 QualType R = TInfo->getType(); 2097 2098 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2099 ForRedeclaration); 2100 2101 // See if this is a redefinition of a variable in the same scope. 2102 if (!D.getCXXScopeSpec().isSet()) { 2103 bool IsLinkageLookup = false; 2104 2105 // If the declaration we're planning to build will be a function 2106 // or object with linkage, then look for another declaration with 2107 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2108 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2109 /* Do nothing*/; 2110 else if (R->isFunctionType()) { 2111 if (CurContext->isFunctionOrMethod() || 2112 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2113 IsLinkageLookup = true; 2114 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2115 IsLinkageLookup = true; 2116 else if (CurContext->getLookupContext()->isTranslationUnit() && 2117 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2118 IsLinkageLookup = true; 2119 2120 if (IsLinkageLookup) 2121 Previous.clear(LookupRedeclarationWithLinkage); 2122 2123 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2124 } else { // Something like "int foo::x;" 2125 LookupQualifiedName(Previous, DC); 2126 2127 // Don't consider using declarations as previous declarations for 2128 // out-of-line members. 2129 RemoveUsingDecls(Previous); 2130 2131 // C++ 7.3.1.2p2: 2132 // Members (including explicit specializations of templates) of a named 2133 // namespace can also be defined outside that namespace by explicit 2134 // qualification of the name being defined, provided that the entity being 2135 // defined was already declared in the namespace and the definition appears 2136 // after the point of declaration in a namespace that encloses the 2137 // declarations namespace. 2138 // 2139 // Note that we only check the context at this point. We don't yet 2140 // have enough information to make sure that PrevDecl is actually 2141 // the declaration we want to match. For example, given: 2142 // 2143 // class X { 2144 // void f(); 2145 // void f(float); 2146 // }; 2147 // 2148 // void X::f(int) { } // ill-formed 2149 // 2150 // In this case, PrevDecl will point to the overload set 2151 // containing the two f's declared in X, but neither of them 2152 // matches. 2153 2154 // First check whether we named the global scope. 2155 if (isa<TranslationUnitDecl>(DC)) { 2156 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2157 << Name << D.getCXXScopeSpec().getRange(); 2158 } else { 2159 DeclContext *Cur = CurContext; 2160 while (isa<LinkageSpecDecl>(Cur)) 2161 Cur = Cur->getParent(); 2162 if (!Cur->Encloses(DC)) { 2163 // The qualifying scope doesn't enclose the original declaration. 2164 // Emit diagnostic based on current scope. 2165 SourceLocation L = D.getIdentifierLoc(); 2166 SourceRange R = D.getCXXScopeSpec().getRange(); 2167 if (isa<FunctionDecl>(Cur)) 2168 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2169 else 2170 Diag(L, diag::err_invalid_declarator_scope) 2171 << Name << cast<NamedDecl>(DC) << R; 2172 D.setInvalidType(); 2173 } 2174 } 2175 } 2176 2177 if (Previous.isSingleResult() && 2178 Previous.getFoundDecl()->isTemplateParameter()) { 2179 // Maybe we will complain about the shadowed template parameter. 2180 if (!D.isInvalidType()) 2181 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2182 Previous.getFoundDecl())) 2183 D.setInvalidType(); 2184 2185 // Just pretend that we didn't see the previous declaration. 2186 Previous.clear(); 2187 } 2188 2189 // In C++, the previous declaration we find might be a tag type 2190 // (class or enum). In this case, the new declaration will hide the 2191 // tag type. Note that this does does not apply if we're declaring a 2192 // typedef (C++ [dcl.typedef]p4). 2193 if (Previous.isSingleTagDecl() && 2194 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2195 Previous.clear(); 2196 2197 bool Redeclaration = false; 2198 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2199 if (TemplateParamLists.size()) { 2200 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2201 return DeclPtrTy(); 2202 } 2203 2204 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2205 } else if (R->isFunctionType()) { 2206 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2207 move(TemplateParamLists), 2208 IsFunctionDefinition, Redeclaration); 2209 } else { 2210 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2211 move(TemplateParamLists), 2212 Redeclaration); 2213 } 2214 2215 if (New == 0) 2216 return DeclPtrTy(); 2217 2218 // If this has an identifier and is not an invalid redeclaration or 2219 // function template specialization, add it to the scope stack. 2220 if (Name && !(Redeclaration && New->isInvalidDecl())) 2221 PushOnScopeChains(New, S); 2222 2223 return DeclPtrTy::make(New); 2224} 2225 2226/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2227/// types into constant array types in certain situations which would otherwise 2228/// be errors (for GCC compatibility). 2229static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2230 ASTContext &Context, 2231 bool &SizeIsNegative) { 2232 // This method tries to turn a variable array into a constant 2233 // array even when the size isn't an ICE. This is necessary 2234 // for compatibility with code that depends on gcc's buggy 2235 // constant expression folding, like struct {char x[(int)(char*)2];} 2236 SizeIsNegative = false; 2237 2238 QualifierCollector Qs; 2239 const Type *Ty = Qs.strip(T); 2240 2241 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2242 QualType Pointee = PTy->getPointeeType(); 2243 QualType FixedType = 2244 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2245 if (FixedType.isNull()) return FixedType; 2246 FixedType = Context.getPointerType(FixedType); 2247 return Qs.apply(FixedType); 2248 } 2249 2250 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2251 if (!VLATy) 2252 return QualType(); 2253 // FIXME: We should probably handle this case 2254 if (VLATy->getElementType()->isVariablyModifiedType()) 2255 return QualType(); 2256 2257 Expr::EvalResult EvalResult; 2258 if (!VLATy->getSizeExpr() || 2259 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2260 !EvalResult.Val.isInt()) 2261 return QualType(); 2262 2263 llvm::APSInt &Res = EvalResult.Val.getInt(); 2264 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2265 // TODO: preserve the size expression in declarator info 2266 return Context.getConstantArrayType(VLATy->getElementType(), 2267 Res, ArrayType::Normal, 0); 2268 } 2269 2270 SizeIsNegative = true; 2271 return QualType(); 2272} 2273 2274/// \brief Register the given locally-scoped external C declaration so 2275/// that it can be found later for redeclarations 2276void 2277Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2278 const LookupResult &Previous, 2279 Scope *S) { 2280 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2281 "Decl is not a locally-scoped decl!"); 2282 // Note that we have a locally-scoped external with this name. 2283 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2284 2285 if (!Previous.isSingleResult()) 2286 return; 2287 2288 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2289 2290 // If there was a previous declaration of this variable, it may be 2291 // in our identifier chain. Update the identifier chain with the new 2292 // declaration. 2293 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2294 // The previous declaration was found on the identifer resolver 2295 // chain, so remove it from its scope. 2296 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2297 S = S->getParent(); 2298 2299 if (S) 2300 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2301 } 2302} 2303 2304/// \brief Diagnose function specifiers on a declaration of an identifier that 2305/// does not identify a function. 2306void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2307 // FIXME: We should probably indicate the identifier in question to avoid 2308 // confusion for constructs like "inline int a(), b;" 2309 if (D.getDeclSpec().isInlineSpecified()) 2310 Diag(D.getDeclSpec().getInlineSpecLoc(), 2311 diag::err_inline_non_function); 2312 2313 if (D.getDeclSpec().isVirtualSpecified()) 2314 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2315 diag::err_virtual_non_function); 2316 2317 if (D.getDeclSpec().isExplicitSpecified()) 2318 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2319 diag::err_explicit_non_function); 2320} 2321 2322NamedDecl* 2323Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2324 QualType R, TypeSourceInfo *TInfo, 2325 LookupResult &Previous, bool &Redeclaration) { 2326 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2327 if (D.getCXXScopeSpec().isSet()) { 2328 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2329 << D.getCXXScopeSpec().getRange(); 2330 D.setInvalidType(); 2331 // Pretend we didn't see the scope specifier. 2332 DC = CurContext; 2333 Previous.clear(); 2334 } 2335 2336 if (getLangOptions().CPlusPlus) { 2337 // Check that there are no default arguments (C++ only). 2338 CheckExtraCXXDefaultArguments(D); 2339 } 2340 2341 DiagnoseFunctionSpecifiers(D); 2342 2343 if (D.getDeclSpec().isThreadSpecified()) 2344 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2345 2346 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2347 if (!NewTD) return 0; 2348 2349 // Handle attributes prior to checking for duplicates in MergeVarDecl 2350 ProcessDeclAttributes(S, NewTD, D); 2351 2352 // Merge the decl with the existing one if appropriate. If the decl is 2353 // in an outer scope, it isn't the same thing. 2354 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2355 if (!Previous.empty()) { 2356 Redeclaration = true; 2357 MergeTypeDefDecl(NewTD, Previous); 2358 } 2359 2360 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2361 // then it shall have block scope. 2362 QualType T = NewTD->getUnderlyingType(); 2363 if (T->isVariablyModifiedType()) { 2364 FunctionNeedsScopeChecking() = true; 2365 2366 if (S->getFnParent() == 0) { 2367 bool SizeIsNegative; 2368 QualType FixedTy = 2369 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2370 if (!FixedTy.isNull()) { 2371 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2372 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2373 } else { 2374 if (SizeIsNegative) 2375 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2376 else if (T->isVariableArrayType()) 2377 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2378 else 2379 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2380 NewTD->setInvalidDecl(); 2381 } 2382 } 2383 } 2384 2385 // If this is the C FILE type, notify the AST context. 2386 if (IdentifierInfo *II = NewTD->getIdentifier()) 2387 if (!NewTD->isInvalidDecl() && 2388 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2389 if (II->isStr("FILE")) 2390 Context.setFILEDecl(NewTD); 2391 else if (II->isStr("jmp_buf")) 2392 Context.setjmp_bufDecl(NewTD); 2393 else if (II->isStr("sigjmp_buf")) 2394 Context.setsigjmp_bufDecl(NewTD); 2395 } 2396 2397 return NewTD; 2398} 2399 2400/// \brief Determines whether the given declaration is an out-of-scope 2401/// previous declaration. 2402/// 2403/// This routine should be invoked when name lookup has found a 2404/// previous declaration (PrevDecl) that is not in the scope where a 2405/// new declaration by the same name is being introduced. If the new 2406/// declaration occurs in a local scope, previous declarations with 2407/// linkage may still be considered previous declarations (C99 2408/// 6.2.2p4-5, C++ [basic.link]p6). 2409/// 2410/// \param PrevDecl the previous declaration found by name 2411/// lookup 2412/// 2413/// \param DC the context in which the new declaration is being 2414/// declared. 2415/// 2416/// \returns true if PrevDecl is an out-of-scope previous declaration 2417/// for a new delcaration with the same name. 2418static bool 2419isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2420 ASTContext &Context) { 2421 if (!PrevDecl) 2422 return 0; 2423 2424 if (!PrevDecl->hasLinkage()) 2425 return false; 2426 2427 if (Context.getLangOptions().CPlusPlus) { 2428 // C++ [basic.link]p6: 2429 // If there is a visible declaration of an entity with linkage 2430 // having the same name and type, ignoring entities declared 2431 // outside the innermost enclosing namespace scope, the block 2432 // scope declaration declares that same entity and receives the 2433 // linkage of the previous declaration. 2434 DeclContext *OuterContext = DC->getLookupContext(); 2435 if (!OuterContext->isFunctionOrMethod()) 2436 // This rule only applies to block-scope declarations. 2437 return false; 2438 else { 2439 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2440 if (PrevOuterContext->isRecord()) 2441 // We found a member function: ignore it. 2442 return false; 2443 else { 2444 // Find the innermost enclosing namespace for the new and 2445 // previous declarations. 2446 while (!OuterContext->isFileContext()) 2447 OuterContext = OuterContext->getParent(); 2448 while (!PrevOuterContext->isFileContext()) 2449 PrevOuterContext = PrevOuterContext->getParent(); 2450 2451 // The previous declaration is in a different namespace, so it 2452 // isn't the same function. 2453 if (OuterContext->getPrimaryContext() != 2454 PrevOuterContext->getPrimaryContext()) 2455 return false; 2456 } 2457 } 2458 } 2459 2460 return true; 2461} 2462 2463static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2464 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2465 if (!SS.isSet()) return; 2466 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2467 SS.getRange()); 2468} 2469 2470NamedDecl* 2471Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2472 QualType R, TypeSourceInfo *TInfo, 2473 LookupResult &Previous, 2474 MultiTemplateParamsArg TemplateParamLists, 2475 bool &Redeclaration) { 2476 DeclarationName Name = GetNameForDeclarator(D); 2477 2478 // Check that there are no default arguments (C++ only). 2479 if (getLangOptions().CPlusPlus) 2480 CheckExtraCXXDefaultArguments(D); 2481 2482 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2483 assert(SCSpec != DeclSpec::SCS_typedef && 2484 "Parser allowed 'typedef' as storage class VarDecl."); 2485 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 2486 if (SCSpec == DeclSpec::SCS_mutable) { 2487 // mutable can only appear on non-static class members, so it's always 2488 // an error here 2489 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2490 D.setInvalidType(); 2491 SC = VarDecl::None; 2492 } 2493 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2494 VarDecl::StorageClass SCAsWritten 2495 = StorageClassSpecToVarDeclStorageClass(SCSpec, DC); 2496 2497 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2498 if (!II) { 2499 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2500 << Name.getAsString(); 2501 return 0; 2502 } 2503 2504 DiagnoseFunctionSpecifiers(D); 2505 2506 if (!DC->isRecord() && S->getFnParent() == 0) { 2507 // C99 6.9p2: The storage-class specifiers auto and register shall not 2508 // appear in the declaration specifiers in an external declaration. 2509 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2510 2511 // If this is a register variable with an asm label specified, then this 2512 // is a GNU extension. 2513 if (SC == VarDecl::Register && D.getAsmLabel()) 2514 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2515 else 2516 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2517 D.setInvalidType(); 2518 } 2519 } 2520 if (DC->isRecord() && !CurContext->isRecord()) { 2521 // This is an out-of-line definition of a static data member. 2522 if (SC == VarDecl::Static) { 2523 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2524 diag::err_static_out_of_line) 2525 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2526 } else if (SC == VarDecl::None) 2527 SC = VarDecl::Static; 2528 } 2529 if (SC == VarDecl::Static) { 2530 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2531 if (RD->isLocalClass()) 2532 Diag(D.getIdentifierLoc(), 2533 diag::err_static_data_member_not_allowed_in_local_class) 2534 << Name << RD->getDeclName(); 2535 } 2536 } 2537 2538 // Match up the template parameter lists with the scope specifier, then 2539 // determine whether we have a template or a template specialization. 2540 bool isExplicitSpecialization = false; 2541 if (TemplateParameterList *TemplateParams 2542 = MatchTemplateParametersToScopeSpecifier( 2543 D.getDeclSpec().getSourceRange().getBegin(), 2544 D.getCXXScopeSpec(), 2545 (TemplateParameterList**)TemplateParamLists.get(), 2546 TemplateParamLists.size(), 2547 /*never a friend*/ false, 2548 isExplicitSpecialization)) { 2549 if (TemplateParams->size() > 0) { 2550 // There is no such thing as a variable template. 2551 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2552 << II 2553 << SourceRange(TemplateParams->getTemplateLoc(), 2554 TemplateParams->getRAngleLoc()); 2555 return 0; 2556 } else { 2557 // There is an extraneous 'template<>' for this variable. Complain 2558 // about it, but allow the declaration of the variable. 2559 Diag(TemplateParams->getTemplateLoc(), 2560 diag::err_template_variable_noparams) 2561 << II 2562 << SourceRange(TemplateParams->getTemplateLoc(), 2563 TemplateParams->getRAngleLoc()); 2564 2565 isExplicitSpecialization = true; 2566 } 2567 } 2568 2569 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2570 II, R, TInfo, SC, SCAsWritten); 2571 2572 if (D.isInvalidType()) 2573 NewVD->setInvalidDecl(); 2574 2575 SetNestedNameSpecifier(NewVD, D); 2576 2577 if (D.getDeclSpec().isThreadSpecified()) { 2578 if (NewVD->hasLocalStorage()) 2579 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2580 else if (!Context.Target.isTLSSupported()) 2581 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2582 else 2583 NewVD->setThreadSpecified(true); 2584 } 2585 2586 // Set the lexical context. If the declarator has a C++ scope specifier, the 2587 // lexical context will be different from the semantic context. 2588 NewVD->setLexicalDeclContext(CurContext); 2589 2590 // Handle attributes prior to checking for duplicates in MergeVarDecl 2591 ProcessDeclAttributes(S, NewVD, D); 2592 2593 // Handle GNU asm-label extension (encoded as an attribute). 2594 if (Expr *E = (Expr*) D.getAsmLabel()) { 2595 // The parser guarantees this is a string. 2596 StringLiteral *SE = cast<StringLiteral>(E); 2597 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2598 } 2599 2600 // Diagnose shadowed variables before filtering for scope. 2601 if (!D.getCXXScopeSpec().isSet()) 2602 CheckShadow(S, NewVD, Previous); 2603 2604 // Don't consider existing declarations that are in a different 2605 // scope and are out-of-semantic-context declarations (if the new 2606 // declaration has linkage). 2607 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2608 2609 // Merge the decl with the existing one if appropriate. 2610 if (!Previous.empty()) { 2611 if (Previous.isSingleResult() && 2612 isa<FieldDecl>(Previous.getFoundDecl()) && 2613 D.getCXXScopeSpec().isSet()) { 2614 // The user tried to define a non-static data member 2615 // out-of-line (C++ [dcl.meaning]p1). 2616 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2617 << D.getCXXScopeSpec().getRange(); 2618 Previous.clear(); 2619 NewVD->setInvalidDecl(); 2620 } 2621 } else if (D.getCXXScopeSpec().isSet()) { 2622 // No previous declaration in the qualifying scope. 2623 Diag(D.getIdentifierLoc(), diag::err_no_member) 2624 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2625 << D.getCXXScopeSpec().getRange(); 2626 NewVD->setInvalidDecl(); 2627 } 2628 2629 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2630 2631 // This is an explicit specialization of a static data member. Check it. 2632 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2633 CheckMemberSpecialization(NewVD, Previous)) 2634 NewVD->setInvalidDecl(); 2635 2636 // attributes declared post-definition are currently ignored 2637 if (Previous.isSingleResult()) { 2638 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2639 if (Def && (Def = Def->getDefinition()) && 2640 Def != NewVD && D.hasAttributes()) { 2641 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2642 Diag(Def->getLocation(), diag::note_previous_definition); 2643 } 2644 } 2645 2646 // If this is a locally-scoped extern C variable, update the map of 2647 // such variables. 2648 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2649 !NewVD->isInvalidDecl()) 2650 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2651 2652 return NewVD; 2653} 2654 2655/// \brief Diagnose variable or built-in function shadowing. Implements 2656/// -Wshadow. 2657/// 2658/// This method is called whenever a VarDecl is added to a "useful" 2659/// scope. 2660/// 2661/// \param S the scope in which the shadowing name is being declared 2662/// \param R the lookup of the name 2663/// 2664void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2665 // Return if warning is ignored. 2666 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2667 return; 2668 2669 // Don't diagnose declarations at file scope. The scope might not 2670 // have a DeclContext if (e.g.) we're parsing a function prototype. 2671 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2672 if (NewDC && NewDC->isFileContext()) 2673 return; 2674 2675 // Only diagnose if we're shadowing an unambiguous field or variable. 2676 if (R.getResultKind() != LookupResult::Found) 2677 return; 2678 2679 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2680 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2681 return; 2682 2683 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2684 2685 // Only warn about certain kinds of shadowing for class members. 2686 if (NewDC && NewDC->isRecord()) { 2687 // In particular, don't warn about shadowing non-class members. 2688 if (!OldDC->isRecord()) 2689 return; 2690 2691 // TODO: should we warn about static data members shadowing 2692 // static data members from base classes? 2693 2694 // TODO: don't diagnose for inaccessible shadowed members. 2695 // This is hard to do perfectly because we might friend the 2696 // shadowing context, but that's just a false negative. 2697 } 2698 2699 // Determine what kind of declaration we're shadowing. 2700 unsigned Kind; 2701 if (isa<RecordDecl>(OldDC)) { 2702 if (isa<FieldDecl>(ShadowedDecl)) 2703 Kind = 3; // field 2704 else 2705 Kind = 2; // static data member 2706 } else if (OldDC->isFileContext()) 2707 Kind = 1; // global 2708 else 2709 Kind = 0; // local 2710 2711 DeclarationName Name = R.getLookupName(); 2712 2713 // Emit warning and note. 2714 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2715 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2716} 2717 2718/// \brief Check -Wshadow without the advantage of a previous lookup. 2719void Sema::CheckShadow(Scope *S, VarDecl *D) { 2720 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2721 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2722 LookupName(R, S); 2723 CheckShadow(S, D, R); 2724} 2725 2726/// \brief Perform semantic checking on a newly-created variable 2727/// declaration. 2728/// 2729/// This routine performs all of the type-checking required for a 2730/// variable declaration once it has been built. It is used both to 2731/// check variables after they have been parsed and their declarators 2732/// have been translated into a declaration, and to check variables 2733/// that have been instantiated from a template. 2734/// 2735/// Sets NewVD->isInvalidDecl() if an error was encountered. 2736void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2737 LookupResult &Previous, 2738 bool &Redeclaration) { 2739 // If the decl is already known invalid, don't check it. 2740 if (NewVD->isInvalidDecl()) 2741 return; 2742 2743 QualType T = NewVD->getType(); 2744 2745 if (T->isObjCObjectType()) { 2746 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2747 return NewVD->setInvalidDecl(); 2748 } 2749 2750 // Emit an error if an address space was applied to decl with local storage. 2751 // This includes arrays of objects with address space qualifiers, but not 2752 // automatic variables that point to other address spaces. 2753 // ISO/IEC TR 18037 S5.1.2 2754 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2755 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2756 return NewVD->setInvalidDecl(); 2757 } 2758 2759 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2760 && !NewVD->hasAttr<BlocksAttr>()) 2761 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2762 2763 bool isVM = T->isVariablyModifiedType(); 2764 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2765 NewVD->hasAttr<BlocksAttr>() || 2766 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2767 // However, this turns on the scope checker for everything with a variable 2768 // which may impact compile time. See if we can find a better solution 2769 // to this, perhaps only checking functions that contain gotos in C++? 2770 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2771 FunctionNeedsScopeChecking() = true; 2772 2773 if ((isVM && NewVD->hasLinkage()) || 2774 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2775 bool SizeIsNegative; 2776 QualType FixedTy = 2777 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2778 2779 if (FixedTy.isNull() && T->isVariableArrayType()) { 2780 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2781 // FIXME: This won't give the correct result for 2782 // int a[10][n]; 2783 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2784 2785 if (NewVD->isFileVarDecl()) 2786 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2787 << SizeRange; 2788 else if (NewVD->getStorageClass() == VarDecl::Static) 2789 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2790 << SizeRange; 2791 else 2792 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2793 << SizeRange; 2794 return NewVD->setInvalidDecl(); 2795 } 2796 2797 if (FixedTy.isNull()) { 2798 if (NewVD->isFileVarDecl()) 2799 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2800 else 2801 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2802 return NewVD->setInvalidDecl(); 2803 } 2804 2805 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2806 NewVD->setType(FixedTy); 2807 } 2808 2809 if (Previous.empty() && NewVD->isExternC()) { 2810 // Since we did not find anything by this name and we're declaring 2811 // an extern "C" variable, look for a non-visible extern "C" 2812 // declaration with the same name. 2813 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2814 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2815 if (Pos != LocallyScopedExternalDecls.end()) 2816 Previous.addDecl(Pos->second); 2817 } 2818 2819 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2820 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2821 << T; 2822 return NewVD->setInvalidDecl(); 2823 } 2824 2825 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2826 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2827 return NewVD->setInvalidDecl(); 2828 } 2829 2830 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2831 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2832 return NewVD->setInvalidDecl(); 2833 } 2834 2835 if (!Previous.empty()) { 2836 Redeclaration = true; 2837 MergeVarDecl(NewVD, Previous); 2838 } 2839} 2840 2841/// \brief Data used with FindOverriddenMethod 2842struct FindOverriddenMethodData { 2843 Sema *S; 2844 CXXMethodDecl *Method; 2845}; 2846 2847/// \brief Member lookup function that determines whether a given C++ 2848/// method overrides a method in a base class, to be used with 2849/// CXXRecordDecl::lookupInBases(). 2850static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2851 CXXBasePath &Path, 2852 void *UserData) { 2853 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2854 2855 FindOverriddenMethodData *Data 2856 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2857 2858 DeclarationName Name = Data->Method->getDeclName(); 2859 2860 // FIXME: Do we care about other names here too? 2861 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2862 // We really want to find the base class constructor here. 2863 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2864 CanQualType CT = Data->S->Context.getCanonicalType(T); 2865 2866 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2867 } 2868 2869 for (Path.Decls = BaseRecord->lookup(Name); 2870 Path.Decls.first != Path.Decls.second; 2871 ++Path.Decls.first) { 2872 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2873 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2874 return true; 2875 } 2876 } 2877 2878 return false; 2879} 2880 2881/// AddOverriddenMethods - See if a method overrides any in the base classes, 2882/// and if so, check that it's a valid override and remember it. 2883void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2884 // Look for virtual methods in base classes that this method might override. 2885 CXXBasePaths Paths; 2886 FindOverriddenMethodData Data; 2887 Data.Method = MD; 2888 Data.S = this; 2889 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2890 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2891 E = Paths.found_decls_end(); I != E; ++I) { 2892 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2893 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2894 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2895 !CheckOverridingFunctionAttributes(MD, OldMD)) 2896 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2897 } 2898 } 2899 } 2900} 2901 2902NamedDecl* 2903Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2904 QualType R, TypeSourceInfo *TInfo, 2905 LookupResult &Previous, 2906 MultiTemplateParamsArg TemplateParamLists, 2907 bool IsFunctionDefinition, bool &Redeclaration) { 2908 assert(R.getTypePtr()->isFunctionType()); 2909 2910 DeclarationName Name = GetNameForDeclarator(D); 2911 FunctionDecl::StorageClass SC = FunctionDecl::None; 2912 switch (D.getDeclSpec().getStorageClassSpec()) { 2913 default: assert(0 && "Unknown storage class!"); 2914 case DeclSpec::SCS_auto: 2915 case DeclSpec::SCS_register: 2916 case DeclSpec::SCS_mutable: 2917 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2918 diag::err_typecheck_sclass_func); 2919 D.setInvalidType(); 2920 break; 2921 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2922 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2923 case DeclSpec::SCS_static: { 2924 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2925 // C99 6.7.1p5: 2926 // The declaration of an identifier for a function that has 2927 // block scope shall have no explicit storage-class specifier 2928 // other than extern 2929 // See also (C++ [dcl.stc]p4). 2930 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2931 diag::err_static_block_func); 2932 SC = FunctionDecl::None; 2933 } else 2934 SC = FunctionDecl::Static; 2935 break; 2936 } 2937 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2938 } 2939 2940 if (D.getDeclSpec().isThreadSpecified()) 2941 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2942 2943 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2944 bool isInline = D.getDeclSpec().isInlineSpecified(); 2945 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2946 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2947 2948 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2949 FunctionDecl::StorageClass SCAsWritten 2950 = StorageClassSpecToFunctionDeclStorageClass(SCSpec, DC); 2951 2952 // Check that the return type is not an abstract class type. 2953 // For record types, this is done by the AbstractClassUsageDiagnoser once 2954 // the class has been completely parsed. 2955 if (!DC->isRecord() && 2956 RequireNonAbstractType(D.getIdentifierLoc(), 2957 R->getAs<FunctionType>()->getResultType(), 2958 diag::err_abstract_type_in_decl, 2959 AbstractReturnType)) 2960 D.setInvalidType(); 2961 2962 // Do not allow returning a objc interface by-value. 2963 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 2964 Diag(D.getIdentifierLoc(), 2965 diag::err_object_cannot_be_passed_returned_by_value) << 0 2966 << R->getAs<FunctionType>()->getResultType(); 2967 D.setInvalidType(); 2968 } 2969 2970 bool isVirtualOkay = false; 2971 FunctionDecl *NewFD; 2972 2973 if (isFriend) { 2974 // C++ [class.friend]p5 2975 // A function can be defined in a friend declaration of a 2976 // class . . . . Such a function is implicitly inline. 2977 isInline |= IsFunctionDefinition; 2978 } 2979 2980 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2981 // This is a C++ constructor declaration. 2982 assert(DC->isRecord() && 2983 "Constructors can only be declared in a member context"); 2984 2985 R = CheckConstructorDeclarator(D, R, SC); 2986 2987 // Create the new declaration 2988 NewFD = CXXConstructorDecl::Create(Context, 2989 cast<CXXRecordDecl>(DC), 2990 D.getIdentifierLoc(), Name, R, TInfo, 2991 isExplicit, isInline, 2992 /*isImplicitlyDeclared=*/false); 2993 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2994 // This is a C++ destructor declaration. 2995 if (DC->isRecord()) { 2996 R = CheckDestructorDeclarator(D, SC); 2997 2998 NewFD = CXXDestructorDecl::Create(Context, 2999 cast<CXXRecordDecl>(DC), 3000 D.getIdentifierLoc(), Name, R, 3001 isInline, 3002 /*isImplicitlyDeclared=*/false); 3003 NewFD->setTypeSourceInfo(TInfo); 3004 3005 isVirtualOkay = true; 3006 } else { 3007 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3008 3009 // Create a FunctionDecl to satisfy the function definition parsing 3010 // code path. 3011 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3012 Name, R, TInfo, SC, SCAsWritten, isInline, 3013 /*hasPrototype=*/true); 3014 D.setInvalidType(); 3015 } 3016 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3017 if (!DC->isRecord()) { 3018 Diag(D.getIdentifierLoc(), 3019 diag::err_conv_function_not_member); 3020 return 0; 3021 } 3022 3023 CheckConversionDeclarator(D, R, SC); 3024 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3025 D.getIdentifierLoc(), Name, R, TInfo, 3026 isInline, isExplicit); 3027 3028 isVirtualOkay = true; 3029 } else if (DC->isRecord()) { 3030 // If the of the function is the same as the name of the record, then this 3031 // must be an invalid constructor that has a return type. 3032 // (The parser checks for a return type and makes the declarator a 3033 // constructor if it has no return type). 3034 // must have an invalid constructor that has a return type 3035 if (Name.getAsIdentifierInfo() && 3036 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3037 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3038 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3039 << SourceRange(D.getIdentifierLoc()); 3040 return 0; 3041 } 3042 3043 bool isStatic = SC == FunctionDecl::Static; 3044 3045 // [class.free]p1: 3046 // Any allocation function for a class T is a static member 3047 // (even if not explicitly declared static). 3048 if (Name.getCXXOverloadedOperator() == OO_New || 3049 Name.getCXXOverloadedOperator() == OO_Array_New) 3050 isStatic = true; 3051 3052 // [class.free]p6 Any deallocation function for a class X is a static member 3053 // (even if not explicitly declared static). 3054 if (Name.getCXXOverloadedOperator() == OO_Delete || 3055 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3056 isStatic = true; 3057 3058 // This is a C++ method declaration. 3059 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3060 D.getIdentifierLoc(), Name, R, TInfo, 3061 isStatic, SCAsWritten, isInline); 3062 3063 isVirtualOkay = !isStatic; 3064 } else { 3065 // Determine whether the function was written with a 3066 // prototype. This true when: 3067 // - we're in C++ (where every function has a prototype), 3068 // - there is a prototype in the declarator, or 3069 // - the type R of the function is some kind of typedef or other reference 3070 // to a type name (which eventually refers to a function type). 3071 bool HasPrototype = 3072 getLangOptions().CPlusPlus || 3073 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3074 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3075 3076 NewFD = FunctionDecl::Create(Context, DC, 3077 D.getIdentifierLoc(), 3078 Name, R, TInfo, SC, SCAsWritten, isInline, 3079 HasPrototype); 3080 } 3081 3082 if (D.isInvalidType()) 3083 NewFD->setInvalidDecl(); 3084 3085 SetNestedNameSpecifier(NewFD, D); 3086 3087 // Set the lexical context. If the declarator has a C++ 3088 // scope specifier, or is the object of a friend declaration, the 3089 // lexical context will be different from the semantic context. 3090 NewFD->setLexicalDeclContext(CurContext); 3091 3092 // Match up the template parameter lists with the scope specifier, then 3093 // determine whether we have a template or a template specialization. 3094 FunctionTemplateDecl *FunctionTemplate = 0; 3095 bool isExplicitSpecialization = false; 3096 bool isFunctionTemplateSpecialization = false; 3097 if (TemplateParameterList *TemplateParams 3098 = MatchTemplateParametersToScopeSpecifier( 3099 D.getDeclSpec().getSourceRange().getBegin(), 3100 D.getCXXScopeSpec(), 3101 (TemplateParameterList**)TemplateParamLists.get(), 3102 TemplateParamLists.size(), 3103 isFriend, 3104 isExplicitSpecialization)) { 3105 if (TemplateParams->size() > 0) { 3106 // This is a function template 3107 3108 // Check that we can declare a template here. 3109 if (CheckTemplateDeclScope(S, TemplateParams)) 3110 return 0; 3111 3112 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3113 NewFD->getLocation(), 3114 Name, TemplateParams, 3115 NewFD); 3116 FunctionTemplate->setLexicalDeclContext(CurContext); 3117 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3118 } else { 3119 // This is a function template specialization. 3120 isFunctionTemplateSpecialization = true; 3121 3122 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3123 if (isFriend && isFunctionTemplateSpecialization) { 3124 // We want to remove the "template<>", found here. 3125 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3126 3127 // If we remove the template<> and the name is not a 3128 // template-id, we're actually silently creating a problem: 3129 // the friend declaration will refer to an untemplated decl, 3130 // and clearly the user wants a template specialization. So 3131 // we need to insert '<>' after the name. 3132 SourceLocation InsertLoc; 3133 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3134 InsertLoc = D.getName().getSourceRange().getEnd(); 3135 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3136 } 3137 3138 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3139 << Name << RemoveRange 3140 << FixItHint::CreateRemoval(RemoveRange) 3141 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3142 } 3143 } 3144 3145 // FIXME: Free this memory properly. 3146 TemplateParamLists.release(); 3147 } 3148 3149 // C++ [dcl.fct.spec]p5: 3150 // The virtual specifier shall only be used in declarations of 3151 // nonstatic class member functions that appear within a 3152 // member-specification of a class declaration; see 10.3. 3153 // 3154 if (isVirtual && !NewFD->isInvalidDecl()) { 3155 if (!isVirtualOkay) { 3156 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3157 diag::err_virtual_non_function); 3158 } else if (!CurContext->isRecord()) { 3159 // 'virtual' was specified outside of the class. 3160 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3161 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3162 } else { 3163 // Okay: Add virtual to the method. 3164 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3165 CurClass->setMethodAsVirtual(NewFD); 3166 } 3167 } 3168 3169 // C++ [dcl.fct.spec]p6: 3170 // The explicit specifier shall be used only in the declaration of a 3171 // constructor or conversion function within its class definition; see 12.3.1 3172 // and 12.3.2. 3173 if (isExplicit && !NewFD->isInvalidDecl()) { 3174 if (!CurContext->isRecord()) { 3175 // 'explicit' was specified outside of the class. 3176 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3177 diag::err_explicit_out_of_class) 3178 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3179 } else if (!isa<CXXConstructorDecl>(NewFD) && 3180 !isa<CXXConversionDecl>(NewFD)) { 3181 // 'explicit' was specified on a function that wasn't a constructor 3182 // or conversion function. 3183 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3184 diag::err_explicit_non_ctor_or_conv_function) 3185 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3186 } 3187 } 3188 3189 // Filter out previous declarations that don't match the scope. 3190 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3191 3192 if (isFriend) { 3193 // DC is the namespace in which the function is being declared. 3194 assert((DC->isFileContext() || !Previous.empty()) && 3195 "previously-undeclared friend function being created " 3196 "in a non-namespace context"); 3197 3198 // For now, claim that the objects have no previous declaration. 3199 if (FunctionTemplate) { 3200 FunctionTemplate->setObjectOfFriendDecl(false); 3201 FunctionTemplate->setAccess(AS_public); 3202 } 3203 NewFD->setObjectOfFriendDecl(false); 3204 NewFD->setAccess(AS_public); 3205 } 3206 3207 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3208 !CurContext->isRecord()) { 3209 // C++ [class.static]p1: 3210 // A data or function member of a class may be declared static 3211 // in a class definition, in which case it is a static member of 3212 // the class. 3213 3214 // Complain about the 'static' specifier if it's on an out-of-line 3215 // member function definition. 3216 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3217 diag::err_static_out_of_line) 3218 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3219 } 3220 3221 // Handle GNU asm-label extension (encoded as an attribute). 3222 if (Expr *E = (Expr*) D.getAsmLabel()) { 3223 // The parser guarantees this is a string. 3224 StringLiteral *SE = cast<StringLiteral>(E); 3225 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3226 } 3227 3228 // Copy the parameter declarations from the declarator D to the function 3229 // declaration NewFD, if they are available. First scavenge them into Params. 3230 llvm::SmallVector<ParmVarDecl*, 16> Params; 3231 if (D.getNumTypeObjects() > 0) { 3232 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3233 3234 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3235 // function that takes no arguments, not a function that takes a 3236 // single void argument. 3237 // We let through "const void" here because Sema::GetTypeForDeclarator 3238 // already checks for that case. 3239 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3240 FTI.ArgInfo[0].Param && 3241 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3242 // Empty arg list, don't push any params. 3243 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3244 3245 // In C++, the empty parameter-type-list must be spelled "void"; a 3246 // typedef of void is not permitted. 3247 if (getLangOptions().CPlusPlus && 3248 Param->getType().getUnqualifiedType() != Context.VoidTy) 3249 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3250 // FIXME: Leaks decl? 3251 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3252 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3253 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3254 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3255 Param->setDeclContext(NewFD); 3256 Params.push_back(Param); 3257 3258 if (Param->isInvalidDecl()) 3259 NewFD->setInvalidDecl(); 3260 } 3261 } 3262 3263 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3264 // When we're declaring a function with a typedef, typeof, etc as in the 3265 // following example, we'll need to synthesize (unnamed) 3266 // parameters for use in the declaration. 3267 // 3268 // @code 3269 // typedef void fn(int); 3270 // fn f; 3271 // @endcode 3272 3273 // Synthesize a parameter for each argument type. 3274 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3275 AE = FT->arg_type_end(); AI != AE; ++AI) { 3276 ParmVarDecl *Param = 3277 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3278 Params.push_back(Param); 3279 } 3280 } else { 3281 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3282 "Should not need args for typedef of non-prototype fn"); 3283 } 3284 // Finally, we know we have the right number of parameters, install them. 3285 NewFD->setParams(Params.data(), Params.size()); 3286 3287 // If the declarator is a template-id, translate the parser's template 3288 // argument list into our AST format. 3289 bool HasExplicitTemplateArgs = false; 3290 TemplateArgumentListInfo TemplateArgs; 3291 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3292 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3293 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3294 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3295 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3296 TemplateId->getTemplateArgs(), 3297 TemplateId->NumArgs); 3298 translateTemplateArguments(TemplateArgsPtr, 3299 TemplateArgs); 3300 TemplateArgsPtr.release(); 3301 3302 HasExplicitTemplateArgs = true; 3303 3304 if (FunctionTemplate) { 3305 // FIXME: Diagnose function template with explicit template 3306 // arguments. 3307 HasExplicitTemplateArgs = false; 3308 } else if (!isFunctionTemplateSpecialization && 3309 !D.getDeclSpec().isFriendSpecified()) { 3310 // We have encountered something that the user meant to be a 3311 // specialization (because it has explicitly-specified template 3312 // arguments) but that was not introduced with a "template<>" (or had 3313 // too few of them). 3314 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3315 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3316 << FixItHint::CreateInsertion( 3317 D.getDeclSpec().getSourceRange().getBegin(), 3318 "template<> "); 3319 isFunctionTemplateSpecialization = true; 3320 } else { 3321 // "friend void foo<>(int);" is an implicit specialization decl. 3322 isFunctionTemplateSpecialization = true; 3323 } 3324 } else if (isFriend && isFunctionTemplateSpecialization) { 3325 // This combination is only possible in a recovery case; the user 3326 // wrote something like: 3327 // template <> friend void foo(int); 3328 // which we're recovering from as if the user had written: 3329 // friend void foo<>(int); 3330 // Go ahead and fake up a template id. 3331 HasExplicitTemplateArgs = true; 3332 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3333 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3334 } 3335 3336 // If it's a friend (and only if it's a friend), it's possible 3337 // that either the specialized function type or the specialized 3338 // template is dependent, and therefore matching will fail. In 3339 // this case, don't check the specialization yet. 3340 if (isFunctionTemplateSpecialization && isFriend && 3341 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3342 assert(HasExplicitTemplateArgs && 3343 "friend function specialization without template args"); 3344 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3345 Previous)) 3346 NewFD->setInvalidDecl(); 3347 } else if (isFunctionTemplateSpecialization) { 3348 if (CheckFunctionTemplateSpecialization(NewFD, 3349 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3350 Previous)) 3351 NewFD->setInvalidDecl(); 3352 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3353 if (CheckMemberSpecialization(NewFD, Previous)) 3354 NewFD->setInvalidDecl(); 3355 } 3356 3357 // Perform semantic checking on the function declaration. 3358 bool OverloadableAttrRequired = false; // FIXME: HACK! 3359 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3360 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3361 3362 assert((NewFD->isInvalidDecl() || !Redeclaration || 3363 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3364 "previous declaration set still overloaded"); 3365 3366 NamedDecl *PrincipalDecl = (FunctionTemplate 3367 ? cast<NamedDecl>(FunctionTemplate) 3368 : NewFD); 3369 3370 if (isFriend && Redeclaration) { 3371 AccessSpecifier Access = AS_public; 3372 if (!NewFD->isInvalidDecl()) 3373 Access = NewFD->getPreviousDeclaration()->getAccess(); 3374 3375 NewFD->setAccess(Access); 3376 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3377 3378 PrincipalDecl->setObjectOfFriendDecl(true); 3379 } 3380 3381 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3382 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3383 PrincipalDecl->setNonMemberOperator(); 3384 3385 // If we have a function template, check the template parameter 3386 // list. This will check and merge default template arguments. 3387 if (FunctionTemplate) { 3388 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3389 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3390 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3391 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3392 : TPC_FunctionTemplate); 3393 } 3394 3395 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3396 // Fake up an access specifier if it's supposed to be a class member. 3397 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3398 NewFD->setAccess(AS_public); 3399 3400 // An out-of-line member function declaration must also be a 3401 // definition (C++ [dcl.meaning]p1). 3402 // Note that this is not the case for explicit specializations of 3403 // function templates or member functions of class templates, per 3404 // C++ [temp.expl.spec]p2. 3405 if (!IsFunctionDefinition && !isFriend && 3406 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3407 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3408 << D.getCXXScopeSpec().getRange(); 3409 NewFD->setInvalidDecl(); 3410 } else if (!Redeclaration && 3411 !(isFriend && CurContext->isDependentContext())) { 3412 // The user tried to provide an out-of-line definition for a 3413 // function that is a member of a class or namespace, but there 3414 // was no such member function declared (C++ [class.mfct]p2, 3415 // C++ [namespace.memdef]p2). For example: 3416 // 3417 // class X { 3418 // void f() const; 3419 // }; 3420 // 3421 // void X::f() { } // ill-formed 3422 // 3423 // Complain about this problem, and attempt to suggest close 3424 // matches (e.g., those that differ only in cv-qualifiers and 3425 // whether the parameter types are references). 3426 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3427 << Name << DC << D.getCXXScopeSpec().getRange(); 3428 NewFD->setInvalidDecl(); 3429 3430 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3431 ForRedeclaration); 3432 LookupQualifiedName(Prev, DC); 3433 assert(!Prev.isAmbiguous() && 3434 "Cannot have an ambiguity in previous-declaration lookup"); 3435 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3436 Func != FuncEnd; ++Func) { 3437 if (isa<FunctionDecl>(*Func) && 3438 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3439 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3440 } 3441 } 3442 } 3443 3444 // Handle attributes. We need to have merged decls when handling attributes 3445 // (for example to check for conflicts, etc). 3446 // FIXME: This needs to happen before we merge declarations. Then, 3447 // let attribute merging cope with attribute conflicts. 3448 ProcessDeclAttributes(S, NewFD, D); 3449 3450 // attributes declared post-definition are currently ignored 3451 if (Redeclaration && Previous.isSingleResult()) { 3452 const FunctionDecl *Def; 3453 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3454 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3455 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3456 Diag(Def->getLocation(), diag::note_previous_definition); 3457 } 3458 } 3459 3460 AddKnownFunctionAttributes(NewFD); 3461 3462 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3463 // If a function name is overloadable in C, then every function 3464 // with that name must be marked "overloadable". 3465 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3466 << Redeclaration << NewFD; 3467 if (!Previous.empty()) 3468 Diag(Previous.getRepresentativeDecl()->getLocation(), 3469 diag::note_attribute_overloadable_prev_overload); 3470 NewFD->addAttr(::new (Context) OverloadableAttr()); 3471 } 3472 3473 // If this is a locally-scoped extern C function, update the 3474 // map of such names. 3475 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3476 && !NewFD->isInvalidDecl()) 3477 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3478 3479 // Set this FunctionDecl's range up to the right paren. 3480 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3481 3482 if (FunctionTemplate && NewFD->isInvalidDecl()) 3483 FunctionTemplate->setInvalidDecl(); 3484 3485 if (FunctionTemplate) 3486 return FunctionTemplate; 3487 3488 3489 // Keep track of static, non-inlined function definitions that 3490 // have not been used. We will warn later. 3491 // FIXME: Also include static functions declared but not defined. 3492 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3493 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3494 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3495 && !NewFD->hasAttr<ConstructorAttr>() 3496 && !NewFD->hasAttr<DestructorAttr>()) 3497 UnusedStaticFuncs.push_back(NewFD); 3498 3499 return NewFD; 3500} 3501 3502/// \brief Perform semantic checking of a new function declaration. 3503/// 3504/// Performs semantic analysis of the new function declaration 3505/// NewFD. This routine performs all semantic checking that does not 3506/// require the actual declarator involved in the declaration, and is 3507/// used both for the declaration of functions as they are parsed 3508/// (called via ActOnDeclarator) and for the declaration of functions 3509/// that have been instantiated via C++ template instantiation (called 3510/// via InstantiateDecl). 3511/// 3512/// \param IsExplicitSpecialiation whether this new function declaration is 3513/// an explicit specialization of the previous declaration. 3514/// 3515/// This sets NewFD->isInvalidDecl() to true if there was an error. 3516void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3517 LookupResult &Previous, 3518 bool IsExplicitSpecialization, 3519 bool &Redeclaration, 3520 bool &OverloadableAttrRequired) { 3521 // If NewFD is already known erroneous, don't do any of this checking. 3522 if (NewFD->isInvalidDecl()) 3523 return; 3524 3525 if (NewFD->getResultType()->isVariablyModifiedType()) { 3526 // Functions returning a variably modified type violate C99 6.7.5.2p2 3527 // because all functions have linkage. 3528 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3529 return NewFD->setInvalidDecl(); 3530 } 3531 3532 if (NewFD->isMain()) 3533 CheckMain(NewFD); 3534 3535 // Check for a previous declaration of this name. 3536 if (Previous.empty() && NewFD->isExternC()) { 3537 // Since we did not find anything by this name and we're declaring 3538 // an extern "C" function, look for a non-visible extern "C" 3539 // declaration with the same name. 3540 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3541 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3542 if (Pos != LocallyScopedExternalDecls.end()) 3543 Previous.addDecl(Pos->second); 3544 } 3545 3546 // Merge or overload the declaration with an existing declaration of 3547 // the same name, if appropriate. 3548 if (!Previous.empty()) { 3549 // Determine whether NewFD is an overload of PrevDecl or 3550 // a declaration that requires merging. If it's an overload, 3551 // there's no more work to do here; we'll just add the new 3552 // function to the scope. 3553 3554 NamedDecl *OldDecl = 0; 3555 if (!AllowOverloadingOfFunction(Previous, Context)) { 3556 Redeclaration = true; 3557 OldDecl = Previous.getFoundDecl(); 3558 } else { 3559 if (!getLangOptions().CPlusPlus) { 3560 OverloadableAttrRequired = true; 3561 3562 // Functions marked "overloadable" must have a prototype (that 3563 // we can't get through declaration merging). 3564 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3565 Diag(NewFD->getLocation(), 3566 diag::err_attribute_overloadable_no_prototype) 3567 << NewFD; 3568 Redeclaration = true; 3569 3570 // Turn this into a variadic function with no parameters. 3571 QualType R = Context.getFunctionType( 3572 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3573 0, 0, true, 0, false, false, 0, 0, 3574 FunctionType::ExtInfo()); 3575 NewFD->setType(R); 3576 return NewFD->setInvalidDecl(); 3577 } 3578 } 3579 3580 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3581 case Ovl_Match: 3582 Redeclaration = true; 3583 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3584 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3585 Redeclaration = false; 3586 } 3587 break; 3588 3589 case Ovl_NonFunction: 3590 Redeclaration = true; 3591 break; 3592 3593 case Ovl_Overload: 3594 Redeclaration = false; 3595 break; 3596 } 3597 } 3598 3599 if (Redeclaration) { 3600 // NewFD and OldDecl represent declarations that need to be 3601 // merged. 3602 if (MergeFunctionDecl(NewFD, OldDecl)) 3603 return NewFD->setInvalidDecl(); 3604 3605 Previous.clear(); 3606 Previous.addDecl(OldDecl); 3607 3608 if (FunctionTemplateDecl *OldTemplateDecl 3609 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3610 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3611 FunctionTemplateDecl *NewTemplateDecl 3612 = NewFD->getDescribedFunctionTemplate(); 3613 assert(NewTemplateDecl && "Template/non-template mismatch"); 3614 if (CXXMethodDecl *Method 3615 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3616 Method->setAccess(OldTemplateDecl->getAccess()); 3617 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3618 } 3619 3620 // If this is an explicit specialization of a member that is a function 3621 // template, mark it as a member specialization. 3622 if (IsExplicitSpecialization && 3623 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3624 NewTemplateDecl->setMemberSpecialization(); 3625 assert(OldTemplateDecl->isMemberSpecialization()); 3626 } 3627 } else { 3628 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3629 NewFD->setAccess(OldDecl->getAccess()); 3630 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3631 } 3632 } 3633 } 3634 3635 // Semantic checking for this function declaration (in isolation). 3636 if (getLangOptions().CPlusPlus) { 3637 // C++-specific checks. 3638 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3639 CheckConstructor(Constructor); 3640 } else if (CXXDestructorDecl *Destructor = 3641 dyn_cast<CXXDestructorDecl>(NewFD)) { 3642 CXXRecordDecl *Record = Destructor->getParent(); 3643 QualType ClassType = Context.getTypeDeclType(Record); 3644 3645 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3646 // type is dependent? Both gcc and edg can handle that. 3647 if (!ClassType->isDependentType()) { 3648 DeclarationName Name 3649 = Context.DeclarationNames.getCXXDestructorName( 3650 Context.getCanonicalType(ClassType)); 3651 if (NewFD->getDeclName() != Name) { 3652 Diag(NewFD->getLocation(), diag::err_destructor_name); 3653 return NewFD->setInvalidDecl(); 3654 } 3655 } 3656 3657 Record->setUserDeclaredDestructor(true); 3658 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3659 // user-defined destructor. 3660 Record->setPOD(false); 3661 3662 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3663 // declared destructor. 3664 // FIXME: C++0x: don't do this for "= default" destructors 3665 Record->setHasTrivialDestructor(false); 3666 } else if (CXXConversionDecl *Conversion 3667 = dyn_cast<CXXConversionDecl>(NewFD)) { 3668 ActOnConversionDeclarator(Conversion); 3669 } 3670 3671 // Find any virtual functions that this function overrides. 3672 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3673 if (!Method->isFunctionTemplateSpecialization() && 3674 !Method->getDescribedFunctionTemplate()) 3675 AddOverriddenMethods(Method->getParent(), Method); 3676 } 3677 3678 // Additional checks for the destructor; make sure we do this after we 3679 // figure out whether the destructor is virtual. 3680 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3681 if (!Destructor->getParent()->isDependentType()) 3682 CheckDestructor(Destructor); 3683 3684 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3685 if (NewFD->isOverloadedOperator() && 3686 CheckOverloadedOperatorDeclaration(NewFD)) 3687 return NewFD->setInvalidDecl(); 3688 3689 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3690 if (NewFD->getLiteralIdentifier() && 3691 CheckLiteralOperatorDeclaration(NewFD)) 3692 return NewFD->setInvalidDecl(); 3693 3694 // In C++, check default arguments now that we have merged decls. Unless 3695 // the lexical context is the class, because in this case this is done 3696 // during delayed parsing anyway. 3697 if (!CurContext->isRecord()) 3698 CheckCXXDefaultArguments(NewFD); 3699 } 3700} 3701 3702void Sema::CheckMain(FunctionDecl* FD) { 3703 // C++ [basic.start.main]p3: A program that declares main to be inline 3704 // or static is ill-formed. 3705 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3706 // shall not appear in a declaration of main. 3707 // static main is not an error under C99, but we should warn about it. 3708 bool isInline = FD->isInlineSpecified(); 3709 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3710 if (isInline || isStatic) { 3711 unsigned diagID = diag::warn_unusual_main_decl; 3712 if (isInline || getLangOptions().CPlusPlus) 3713 diagID = diag::err_unusual_main_decl; 3714 3715 int which = isStatic + (isInline << 1) - 1; 3716 Diag(FD->getLocation(), diagID) << which; 3717 } 3718 3719 QualType T = FD->getType(); 3720 assert(T->isFunctionType() && "function decl is not of function type"); 3721 const FunctionType* FT = T->getAs<FunctionType>(); 3722 3723 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3724 // TODO: add a replacement fixit to turn the return type into 'int'. 3725 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3726 FD->setInvalidDecl(true); 3727 } 3728 3729 // Treat protoless main() as nullary. 3730 if (isa<FunctionNoProtoType>(FT)) return; 3731 3732 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3733 unsigned nparams = FTP->getNumArgs(); 3734 assert(FD->getNumParams() == nparams); 3735 3736 bool HasExtraParameters = (nparams > 3); 3737 3738 // Darwin passes an undocumented fourth argument of type char**. If 3739 // other platforms start sprouting these, the logic below will start 3740 // getting shifty. 3741 if (nparams == 4 && 3742 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3743 HasExtraParameters = false; 3744 3745 if (HasExtraParameters) { 3746 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3747 FD->setInvalidDecl(true); 3748 nparams = 3; 3749 } 3750 3751 // FIXME: a lot of the following diagnostics would be improved 3752 // if we had some location information about types. 3753 3754 QualType CharPP = 3755 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3756 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3757 3758 for (unsigned i = 0; i < nparams; ++i) { 3759 QualType AT = FTP->getArgType(i); 3760 3761 bool mismatch = true; 3762 3763 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3764 mismatch = false; 3765 else if (Expected[i] == CharPP) { 3766 // As an extension, the following forms are okay: 3767 // char const ** 3768 // char const * const * 3769 // char * const * 3770 3771 QualifierCollector qs; 3772 const PointerType* PT; 3773 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3774 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3775 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3776 qs.removeConst(); 3777 mismatch = !qs.empty(); 3778 } 3779 } 3780 3781 if (mismatch) { 3782 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3783 // TODO: suggest replacing given type with expected type 3784 FD->setInvalidDecl(true); 3785 } 3786 } 3787 3788 if (nparams == 1 && !FD->isInvalidDecl()) { 3789 Diag(FD->getLocation(), diag::warn_main_one_arg); 3790 } 3791} 3792 3793bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3794 // FIXME: Need strict checking. In C89, we need to check for 3795 // any assignment, increment, decrement, function-calls, or 3796 // commas outside of a sizeof. In C99, it's the same list, 3797 // except that the aforementioned are allowed in unevaluated 3798 // expressions. Everything else falls under the 3799 // "may accept other forms of constant expressions" exception. 3800 // (We never end up here for C++, so the constant expression 3801 // rules there don't matter.) 3802 if (Init->isConstantInitializer(Context)) 3803 return false; 3804 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3805 << Init->getSourceRange(); 3806 return true; 3807} 3808 3809void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3810 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3811} 3812 3813/// AddInitializerToDecl - Adds the initializer Init to the 3814/// declaration dcl. If DirectInit is true, this is C++ direct 3815/// initialization rather than copy initialization. 3816void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3817 Decl *RealDecl = dcl.getAs<Decl>(); 3818 // If there is no declaration, there was an error parsing it. Just ignore 3819 // the initializer. 3820 if (RealDecl == 0) 3821 return; 3822 3823 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3824 // With declarators parsed the way they are, the parser cannot 3825 // distinguish between a normal initializer and a pure-specifier. 3826 // Thus this grotesque test. 3827 IntegerLiteral *IL; 3828 Expr *Init = static_cast<Expr *>(init.get()); 3829 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3830 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3831 CheckPureMethod(Method, Init->getSourceRange()); 3832 else { 3833 Diag(Method->getLocation(), diag::err_member_function_initialization) 3834 << Method->getDeclName() << Init->getSourceRange(); 3835 Method->setInvalidDecl(); 3836 } 3837 return; 3838 } 3839 3840 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3841 if (!VDecl) { 3842 if (getLangOptions().CPlusPlus && 3843 RealDecl->getLexicalDeclContext()->isRecord() && 3844 isa<NamedDecl>(RealDecl)) 3845 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3846 << cast<NamedDecl>(RealDecl)->getDeclName(); 3847 else 3848 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3849 RealDecl->setInvalidDecl(); 3850 return; 3851 } 3852 3853 // A definition must end up with a complete type, which means it must be 3854 // complete with the restriction that an array type might be completed by the 3855 // initializer; note that later code assumes this restriction. 3856 QualType BaseDeclType = VDecl->getType(); 3857 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3858 BaseDeclType = Array->getElementType(); 3859 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3860 diag::err_typecheck_decl_incomplete_type)) { 3861 RealDecl->setInvalidDecl(); 3862 return; 3863 } 3864 3865 // The variable can not have an abstract class type. 3866 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3867 diag::err_abstract_type_in_decl, 3868 AbstractVariableType)) 3869 VDecl->setInvalidDecl(); 3870 3871 const VarDecl *Def; 3872 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3873 Diag(VDecl->getLocation(), diag::err_redefinition) 3874 << VDecl->getDeclName(); 3875 Diag(Def->getLocation(), diag::note_previous_definition); 3876 VDecl->setInvalidDecl(); 3877 return; 3878 } 3879 3880 // Take ownership of the expression, now that we're sure we have somewhere 3881 // to put it. 3882 Expr *Init = init.takeAs<Expr>(); 3883 assert(Init && "missing initializer"); 3884 3885 // Capture the variable that is being initialized and the style of 3886 // initialization. 3887 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3888 3889 // FIXME: Poor source location information. 3890 InitializationKind Kind 3891 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3892 Init->getLocStart(), 3893 Init->getLocEnd()) 3894 : InitializationKind::CreateCopy(VDecl->getLocation(), 3895 Init->getLocStart()); 3896 3897 // Get the decls type and save a reference for later, since 3898 // CheckInitializerTypes may change it. 3899 QualType DclT = VDecl->getType(), SavT = DclT; 3900 if (VDecl->isBlockVarDecl()) { 3901 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3902 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3903 VDecl->setInvalidDecl(); 3904 } else if (!VDecl->isInvalidDecl()) { 3905 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3906 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3907 MultiExprArg(*this, (void**)&Init, 1), 3908 &DclT); 3909 if (Result.isInvalid()) { 3910 VDecl->setInvalidDecl(); 3911 return; 3912 } 3913 3914 Init = Result.takeAs<Expr>(); 3915 3916 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3917 // Don't check invalid declarations to avoid emitting useless diagnostics. 3918 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3919 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3920 CheckForConstantInitializer(Init, DclT); 3921 } 3922 } 3923 } else if (VDecl->isStaticDataMember() && 3924 VDecl->getLexicalDeclContext()->isRecord()) { 3925 // This is an in-class initialization for a static data member, e.g., 3926 // 3927 // struct S { 3928 // static const int value = 17; 3929 // }; 3930 3931 // Attach the initializer 3932 VDecl->setInit(Init); 3933 3934 // C++ [class.mem]p4: 3935 // A member-declarator can contain a constant-initializer only 3936 // if it declares a static member (9.4) of const integral or 3937 // const enumeration type, see 9.4.2. 3938 QualType T = VDecl->getType(); 3939 if (!T->isDependentType() && 3940 (!Context.getCanonicalType(T).isConstQualified() || 3941 !T->isIntegralType())) { 3942 Diag(VDecl->getLocation(), diag::err_member_initialization) 3943 << VDecl->getDeclName() << Init->getSourceRange(); 3944 VDecl->setInvalidDecl(); 3945 } else { 3946 // C++ [class.static.data]p4: 3947 // If a static data member is of const integral or const 3948 // enumeration type, its declaration in the class definition 3949 // can specify a constant-initializer which shall be an 3950 // integral constant expression (5.19). 3951 if (!Init->isTypeDependent() && 3952 !Init->getType()->isIntegralType()) { 3953 // We have a non-dependent, non-integral or enumeration type. 3954 Diag(Init->getSourceRange().getBegin(), 3955 diag::err_in_class_initializer_non_integral_type) 3956 << Init->getType() << Init->getSourceRange(); 3957 VDecl->setInvalidDecl(); 3958 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3959 // Check whether the expression is a constant expression. 3960 llvm::APSInt Value; 3961 SourceLocation Loc; 3962 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3963 Diag(Loc, diag::err_in_class_initializer_non_constant) 3964 << Init->getSourceRange(); 3965 VDecl->setInvalidDecl(); 3966 } else if (!VDecl->getType()->isDependentType()) 3967 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3968 } 3969 } 3970 } else if (VDecl->isFileVarDecl()) { 3971 if (VDecl->getStorageClass() == VarDecl::Extern && 3972 (!getLangOptions().CPlusPlus || 3973 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 3974 Diag(VDecl->getLocation(), diag::warn_extern_init); 3975 if (!VDecl->isInvalidDecl()) { 3976 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3977 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3978 MultiExprArg(*this, (void**)&Init, 1), 3979 &DclT); 3980 if (Result.isInvalid()) { 3981 VDecl->setInvalidDecl(); 3982 return; 3983 } 3984 3985 Init = Result.takeAs<Expr>(); 3986 } 3987 3988 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3989 // Don't check invalid declarations to avoid emitting useless diagnostics. 3990 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3991 // C99 6.7.8p4. All file scoped initializers need to be constant. 3992 CheckForConstantInitializer(Init, DclT); 3993 } 3994 } 3995 // If the type changed, it means we had an incomplete type that was 3996 // completed by the initializer. For example: 3997 // int ary[] = { 1, 3, 5 }; 3998 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3999 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4000 VDecl->setType(DclT); 4001 Init->setType(DclT); 4002 } 4003 4004 Init = MaybeCreateCXXExprWithTemporaries(Init); 4005 // Attach the initializer to the decl. 4006 VDecl->setInit(Init); 4007 4008 if (getLangOptions().CPlusPlus) { 4009 // Make sure we mark the destructor as used if necessary. 4010 QualType InitType = VDecl->getType(); 4011 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4012 InitType = Context.getBaseElementType(Array); 4013 if (const RecordType *Record = InitType->getAs<RecordType>()) 4014 FinalizeVarWithDestructor(VDecl, Record); 4015 } 4016 4017 return; 4018} 4019 4020/// ActOnInitializerError - Given that there was an error parsing an 4021/// initializer for the given declaration, try to return to some form 4022/// of sanity. 4023void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4024 // Our main concern here is re-establishing invariants like "a 4025 // variable's type is either dependent or complete". 4026 Decl *D = dcl.getAs<Decl>(); 4027 if (!D || D->isInvalidDecl()) return; 4028 4029 VarDecl *VD = dyn_cast<VarDecl>(D); 4030 if (!VD) return; 4031 4032 QualType Ty = VD->getType(); 4033 if (Ty->isDependentType()) return; 4034 4035 // Require a complete type. 4036 if (RequireCompleteType(VD->getLocation(), 4037 Context.getBaseElementType(Ty), 4038 diag::err_typecheck_decl_incomplete_type)) { 4039 VD->setInvalidDecl(); 4040 return; 4041 } 4042 4043 // Require an abstract type. 4044 if (RequireNonAbstractType(VD->getLocation(), Ty, 4045 diag::err_abstract_type_in_decl, 4046 AbstractVariableType)) { 4047 VD->setInvalidDecl(); 4048 return; 4049 } 4050 4051 // Don't bother complaining about constructors or destructors, 4052 // though. 4053} 4054 4055void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4056 bool TypeContainsUndeducedAuto) { 4057 Decl *RealDecl = dcl.getAs<Decl>(); 4058 4059 // If there is no declaration, there was an error parsing it. Just ignore it. 4060 if (RealDecl == 0) 4061 return; 4062 4063 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4064 QualType Type = Var->getType(); 4065 4066 // C++0x [dcl.spec.auto]p3 4067 if (TypeContainsUndeducedAuto) { 4068 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4069 << Var->getDeclName() << Type; 4070 Var->setInvalidDecl(); 4071 return; 4072 } 4073 4074 switch (Var->isThisDeclarationADefinition()) { 4075 case VarDecl::Definition: 4076 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4077 break; 4078 4079 // We have an out-of-line definition of a static data member 4080 // that has an in-class initializer, so we type-check this like 4081 // a declaration. 4082 // 4083 // Fall through 4084 4085 case VarDecl::DeclarationOnly: 4086 // It's only a declaration. 4087 4088 // Block scope. C99 6.7p7: If an identifier for an object is 4089 // declared with no linkage (C99 6.2.2p6), the type for the 4090 // object shall be complete. 4091 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4092 !Var->getLinkage() && !Var->isInvalidDecl() && 4093 RequireCompleteType(Var->getLocation(), Type, 4094 diag::err_typecheck_decl_incomplete_type)) 4095 Var->setInvalidDecl(); 4096 4097 // Make sure that the type is not abstract. 4098 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4099 RequireNonAbstractType(Var->getLocation(), Type, 4100 diag::err_abstract_type_in_decl, 4101 AbstractVariableType)) 4102 Var->setInvalidDecl(); 4103 return; 4104 4105 case VarDecl::TentativeDefinition: 4106 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4107 // object that has file scope without an initializer, and without a 4108 // storage-class specifier or with the storage-class specifier "static", 4109 // constitutes a tentative definition. Note: A tentative definition with 4110 // external linkage is valid (C99 6.2.2p5). 4111 if (!Var->isInvalidDecl()) { 4112 if (const IncompleteArrayType *ArrayT 4113 = Context.getAsIncompleteArrayType(Type)) { 4114 if (RequireCompleteType(Var->getLocation(), 4115 ArrayT->getElementType(), 4116 diag::err_illegal_decl_array_incomplete_type)) 4117 Var->setInvalidDecl(); 4118 } else if (Var->getStorageClass() == VarDecl::Static) { 4119 // C99 6.9.2p3: If the declaration of an identifier for an object is 4120 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4121 // declared type shall not be an incomplete type. 4122 // NOTE: code such as the following 4123 // static struct s; 4124 // struct s { int a; }; 4125 // is accepted by gcc. Hence here we issue a warning instead of 4126 // an error and we do not invalidate the static declaration. 4127 // NOTE: to avoid multiple warnings, only check the first declaration. 4128 if (Var->getPreviousDeclaration() == 0) 4129 RequireCompleteType(Var->getLocation(), Type, 4130 diag::ext_typecheck_decl_incomplete_type); 4131 } 4132 } 4133 4134 // Record the tentative definition; we're done. 4135 if (!Var->isInvalidDecl()) 4136 TentativeDefinitions.push_back(Var); 4137 return; 4138 } 4139 4140 // Provide a specific diagnostic for uninitialized variable 4141 // definitions with incomplete array type. 4142 if (Type->isIncompleteArrayType()) { 4143 Diag(Var->getLocation(), 4144 diag::err_typecheck_incomplete_array_needs_initializer); 4145 Var->setInvalidDecl(); 4146 return; 4147 } 4148 4149 // Provide a specific diagnostic for uninitialized variable 4150 // definitions with reference type. 4151 if (Type->isReferenceType()) { 4152 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4153 << Var->getDeclName() 4154 << SourceRange(Var->getLocation(), Var->getLocation()); 4155 Var->setInvalidDecl(); 4156 return; 4157 } 4158 4159 // Do not attempt to type-check the default initializer for a 4160 // variable with dependent type. 4161 if (Type->isDependentType()) 4162 return; 4163 4164 if (Var->isInvalidDecl()) 4165 return; 4166 4167 if (RequireCompleteType(Var->getLocation(), 4168 Context.getBaseElementType(Type), 4169 diag::err_typecheck_decl_incomplete_type)) { 4170 Var->setInvalidDecl(); 4171 return; 4172 } 4173 4174 // The variable can not have an abstract class type. 4175 if (RequireNonAbstractType(Var->getLocation(), Type, 4176 diag::err_abstract_type_in_decl, 4177 AbstractVariableType)) { 4178 Var->setInvalidDecl(); 4179 return; 4180 } 4181 4182 const RecordType *Record 4183 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4184 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4185 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4186 // C++03 [dcl.init]p9: 4187 // If no initializer is specified for an object, and the 4188 // object is of (possibly cv-qualified) non-POD class type (or 4189 // array thereof), the object shall be default-initialized; if 4190 // the object is of const-qualified type, the underlying class 4191 // type shall have a user-declared default 4192 // constructor. Otherwise, if no initializer is specified for 4193 // a non- static object, the object and its subobjects, if 4194 // any, have an indeterminate initial value); if the object 4195 // or any of its subobjects are of const-qualified type, the 4196 // program is ill-formed. 4197 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4198 } else { 4199 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4200 InitializationKind Kind 4201 = InitializationKind::CreateDefault(Var->getLocation()); 4202 4203 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4204 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4205 MultiExprArg(*this, 0, 0)); 4206 if (Init.isInvalid()) 4207 Var->setInvalidDecl(); 4208 else if (Init.get()) 4209 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4210 } 4211 4212 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4213 FinalizeVarWithDestructor(Var, Record); 4214 } 4215} 4216 4217Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4218 DeclPtrTy *Group, 4219 unsigned NumDecls) { 4220 llvm::SmallVector<Decl*, 8> Decls; 4221 4222 if (DS.isTypeSpecOwned()) 4223 Decls.push_back((Decl*)DS.getTypeRep()); 4224 4225 for (unsigned i = 0; i != NumDecls; ++i) 4226 if (Decl *D = Group[i].getAs<Decl>()) 4227 Decls.push_back(D); 4228 4229 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4230 Decls.data(), Decls.size())); 4231} 4232 4233 4234/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4235/// to introduce parameters into function prototype scope. 4236Sema::DeclPtrTy 4237Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4238 const DeclSpec &DS = D.getDeclSpec(); 4239 4240 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4241 VarDecl::StorageClass StorageClass = VarDecl::None; 4242 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4243 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4244 StorageClass = VarDecl::Register; 4245 StorageClassAsWritten = VarDecl::Register; 4246 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4247 Diag(DS.getStorageClassSpecLoc(), 4248 diag::err_invalid_storage_class_in_func_decl); 4249 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4250 } 4251 4252 if (D.getDeclSpec().isThreadSpecified()) 4253 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4254 4255 DiagnoseFunctionSpecifiers(D); 4256 4257 // Check that there are no default arguments inside the type of this 4258 // parameter (C++ only). 4259 if (getLangOptions().CPlusPlus) 4260 CheckExtraCXXDefaultArguments(D); 4261 4262 TagDecl *OwnedDecl = 0; 4263 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4264 QualType parmDeclType = TInfo->getType(); 4265 4266 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4267 // C++ [dcl.fct]p6: 4268 // Types shall not be defined in return or parameter types. 4269 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4270 << Context.getTypeDeclType(OwnedDecl); 4271 } 4272 4273 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4274 IdentifierInfo *II = D.getIdentifier(); 4275 if (II) { 4276 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4277 ForRedeclaration); 4278 LookupName(R, S); 4279 if (R.isSingleResult()) { 4280 NamedDecl *PrevDecl = R.getFoundDecl(); 4281 if (PrevDecl->isTemplateParameter()) { 4282 // Maybe we will complain about the shadowed template parameter. 4283 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4284 // Just pretend that we didn't see the previous declaration. 4285 PrevDecl = 0; 4286 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4287 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4288 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4289 4290 // Recover by removing the name 4291 II = 0; 4292 D.SetIdentifier(0, D.getIdentifierLoc()); 4293 D.setInvalidType(true); 4294 } 4295 } 4296 } 4297 4298 // Temporarily put parameter variables in the translation unit, not 4299 // the enclosing context. This prevents them from accidentally 4300 // looking like class members in C++. 4301 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4302 TInfo, parmDeclType, II, 4303 D.getIdentifierLoc(), 4304 StorageClass, StorageClassAsWritten); 4305 4306 if (D.isInvalidType()) 4307 New->setInvalidDecl(); 4308 4309 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4310 if (D.getCXXScopeSpec().isSet()) { 4311 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4312 << D.getCXXScopeSpec().getRange(); 4313 New->setInvalidDecl(); 4314 } 4315 4316 // Add the parameter declaration into this scope. 4317 S->AddDecl(DeclPtrTy::make(New)); 4318 if (II) 4319 IdResolver.AddDecl(New); 4320 4321 ProcessDeclAttributes(S, New, D); 4322 4323 if (New->hasAttr<BlocksAttr>()) { 4324 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4325 } 4326 return DeclPtrTy::make(New); 4327} 4328 4329/// \brief Synthesizes a variable for a parameter arising from a 4330/// typedef. 4331ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4332 SourceLocation Loc, 4333 QualType T) { 4334 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4335 T, Context.getTrivialTypeSourceInfo(T, Loc), 4336 VarDecl::None, VarDecl::None, 0); 4337 Param->setImplicit(); 4338 return Param; 4339} 4340 4341ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4342 TypeSourceInfo *TSInfo, QualType T, 4343 IdentifierInfo *Name, 4344 SourceLocation NameLoc, 4345 VarDecl::StorageClass StorageClass, 4346 VarDecl::StorageClass StorageClassAsWritten) { 4347 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4348 adjustParameterType(T), TSInfo, 4349 StorageClass, StorageClassAsWritten, 4350 0); 4351 4352 // Parameters can not be abstract class types. 4353 // For record types, this is done by the AbstractClassUsageDiagnoser once 4354 // the class has been completely parsed. 4355 if (!CurContext->isRecord() && 4356 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4357 AbstractParamType)) 4358 New->setInvalidDecl(); 4359 4360 // Parameter declarators cannot be interface types. All ObjC objects are 4361 // passed by reference. 4362 if (T->isObjCObjectType()) { 4363 Diag(NameLoc, 4364 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4365 New->setInvalidDecl(); 4366 } 4367 4368 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4369 // duration shall not be qualified by an address-space qualifier." 4370 // Since all parameters have automatic store duration, they can not have 4371 // an address space. 4372 if (T.getAddressSpace() != 0) { 4373 Diag(NameLoc, diag::err_arg_with_address_space); 4374 New->setInvalidDecl(); 4375 } 4376 4377 return New; 4378} 4379 4380void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4381 SourceLocation LocAfterDecls) { 4382 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4383 "Not a function declarator!"); 4384 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4385 4386 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4387 // for a K&R function. 4388 if (!FTI.hasPrototype) { 4389 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4390 --i; 4391 if (FTI.ArgInfo[i].Param == 0) { 4392 llvm::SmallString<256> Code; 4393 llvm::raw_svector_ostream(Code) << " int " 4394 << FTI.ArgInfo[i].Ident->getName() 4395 << ";\n"; 4396 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4397 << FTI.ArgInfo[i].Ident 4398 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4399 4400 // Implicitly declare the argument as type 'int' for lack of a better 4401 // type. 4402 DeclSpec DS; 4403 const char* PrevSpec; // unused 4404 unsigned DiagID; // unused 4405 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4406 PrevSpec, DiagID); 4407 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4408 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4409 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4410 } 4411 } 4412 } 4413} 4414 4415Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4416 Declarator &D) { 4417 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4418 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4419 "Not a function declarator!"); 4420 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4421 4422 if (FTI.hasPrototype) { 4423 // FIXME: Diagnose arguments without names in C. 4424 } 4425 4426 Scope *ParentScope = FnBodyScope->getParent(); 4427 4428 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4429 MultiTemplateParamsArg(*this), 4430 /*IsFunctionDefinition=*/true); 4431 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4432} 4433 4434static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4435 // Don't warn about invalid declarations. 4436 if (FD->isInvalidDecl()) 4437 return false; 4438 4439 // Or declarations that aren't global. 4440 if (!FD->isGlobal()) 4441 return false; 4442 4443 // Don't warn about C++ member functions. 4444 if (isa<CXXMethodDecl>(FD)) 4445 return false; 4446 4447 // Don't warn about 'main'. 4448 if (FD->isMain()) 4449 return false; 4450 4451 // Don't warn about inline functions. 4452 if (FD->isInlineSpecified()) 4453 return false; 4454 4455 // Don't warn about function templates. 4456 if (FD->getDescribedFunctionTemplate()) 4457 return false; 4458 4459 // Don't warn about function template specializations. 4460 if (FD->isFunctionTemplateSpecialization()) 4461 return false; 4462 4463 bool MissingPrototype = true; 4464 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4465 Prev; Prev = Prev->getPreviousDeclaration()) { 4466 // Ignore any declarations that occur in function or method 4467 // scope, because they aren't visible from the header. 4468 if (Prev->getDeclContext()->isFunctionOrMethod()) 4469 continue; 4470 4471 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4472 break; 4473 } 4474 4475 return MissingPrototype; 4476} 4477 4478Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4479 // Clear the last template instantiation error context. 4480 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4481 4482 if (!D) 4483 return D; 4484 FunctionDecl *FD = 0; 4485 4486 if (FunctionTemplateDecl *FunTmpl 4487 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4488 FD = FunTmpl->getTemplatedDecl(); 4489 else 4490 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4491 4492 // Enter a new function scope 4493 PushFunctionScope(); 4494 4495 // See if this is a redefinition. 4496 // But don't complain if we're in GNU89 mode and the previous definition 4497 // was an extern inline function. 4498 const FunctionDecl *Definition; 4499 if (FD->getBody(Definition) && 4500 !canRedefineFunction(Definition, getLangOptions())) { 4501 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4502 Diag(Definition->getLocation(), diag::note_previous_definition); 4503 } 4504 4505 // Builtin functions cannot be defined. 4506 if (unsigned BuiltinID = FD->getBuiltinID()) { 4507 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4508 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4509 FD->setInvalidDecl(); 4510 } 4511 } 4512 4513 // The return type of a function definition must be complete 4514 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4515 QualType ResultType = FD->getResultType(); 4516 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4517 !FD->isInvalidDecl() && 4518 RequireCompleteType(FD->getLocation(), ResultType, 4519 diag::err_func_def_incomplete_result)) 4520 FD->setInvalidDecl(); 4521 4522 // GNU warning -Wmissing-prototypes: 4523 // Warn if a global function is defined without a previous 4524 // prototype declaration. This warning is issued even if the 4525 // definition itself provides a prototype. The aim is to detect 4526 // global functions that fail to be declared in header files. 4527 if (ShouldWarnAboutMissingPrototype(FD)) 4528 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4529 4530 if (FnBodyScope) 4531 PushDeclContext(FnBodyScope, FD); 4532 4533 // Check the validity of our function parameters 4534 CheckParmsForFunctionDef(FD); 4535 4536 bool ShouldCheckShadow = 4537 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4538 4539 // Introduce our parameters into the function scope 4540 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4541 ParmVarDecl *Param = FD->getParamDecl(p); 4542 Param->setOwningFunction(FD); 4543 4544 // If this has an identifier, add it to the scope stack. 4545 if (Param->getIdentifier() && FnBodyScope) { 4546 if (ShouldCheckShadow) 4547 CheckShadow(FnBodyScope, Param); 4548 4549 PushOnScopeChains(Param, FnBodyScope); 4550 } 4551 } 4552 4553 // Checking attributes of current function definition 4554 // dllimport attribute. 4555 if (FD->getAttr<DLLImportAttr>() && 4556 (!FD->getAttr<DLLExportAttr>())) { 4557 // dllimport attribute cannot be applied to definition. 4558 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4559 Diag(FD->getLocation(), 4560 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4561 << "dllimport"; 4562 FD->setInvalidDecl(); 4563 return DeclPtrTy::make(FD); 4564 } 4565 4566 // Visual C++ appears to not think this is an issue, so only issue 4567 // a warning when Microsoft extensions are disabled. 4568 if (!LangOpts.Microsoft) { 4569 // If a symbol previously declared dllimport is later defined, the 4570 // attribute is ignored in subsequent references, and a warning is 4571 // emitted. 4572 Diag(FD->getLocation(), 4573 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4574 << FD->getNameAsCString() << "dllimport"; 4575 } 4576 } 4577 return DeclPtrTy::make(FD); 4578} 4579 4580/// \brief Given the set of return statements within a function body, 4581/// compute the variables that are subject to the named return value 4582/// optimization. 4583/// 4584/// Each of the variables that is subject to the named return value 4585/// optimization will be marked as NRVO variables in the AST, and any 4586/// return statement that has a marked NRVO variable as its NRVO candidate can 4587/// use the named return value optimization. 4588/// 4589/// This function applies a very simplistic algorithm for NRVO: if every return 4590/// statement in the function has the same NRVO candidate, that candidate is 4591/// the NRVO variable. 4592/// 4593/// FIXME: Employ a smarter algorithm that accounts for multiple return 4594/// statements and the lifetimes of the NRVO candidates. We should be able to 4595/// find a maximal set of NRVO variables. 4596static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4597 const VarDecl *NRVOCandidate = 0; 4598 for (unsigned I = 0; I != NumReturns; ++I) { 4599 if (!Returns[I]->getNRVOCandidate()) 4600 return; 4601 4602 if (!NRVOCandidate) 4603 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4604 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4605 return; 4606 } 4607 4608 if (NRVOCandidate) 4609 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4610} 4611 4612Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4613 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4614} 4615 4616Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4617 bool IsInstantiation) { 4618 Decl *dcl = D.getAs<Decl>(); 4619 Stmt *Body = BodyArg.takeAs<Stmt>(); 4620 4621 FunctionDecl *FD = 0; 4622 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4623 if (FunTmpl) 4624 FD = FunTmpl->getTemplatedDecl(); 4625 else 4626 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4627 4628 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4629 4630 if (FD) { 4631 FD->setBody(Body); 4632 if (FD->isMain()) { 4633 // C and C++ allow for main to automagically return 0. 4634 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4635 FD->setHasImplicitReturnZero(true); 4636 WP.disableCheckFallThrough(); 4637 } 4638 4639 if (!FD->isInvalidDecl()) { 4640 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4641 4642 // If this is a constructor, we need a vtable. 4643 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4644 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4645 4646 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4647 FunctionScopes.back()->Returns.size()); 4648 } 4649 4650 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4651 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4652 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4653 MD->setBody(Body); 4654 MD->setEndLoc(Body->getLocEnd()); 4655 if (!MD->isInvalidDecl()) 4656 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4657 } else { 4658 Body->Destroy(Context); 4659 return DeclPtrTy(); 4660 } 4661 4662 // Verify and clean out per-function state. 4663 4664 // Check goto/label use. 4665 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4666 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4667 LabelStmt *L = I->second; 4668 4669 // Verify that we have no forward references left. If so, there was a goto 4670 // or address of a label taken, but no definition of it. Label fwd 4671 // definitions are indicated with a null substmt. 4672 if (L->getSubStmt() != 0) 4673 continue; 4674 4675 // Emit error. 4676 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4677 4678 // At this point, we have gotos that use the bogus label. Stitch it into 4679 // the function body so that they aren't leaked and that the AST is well 4680 // formed. 4681 if (Body == 0) { 4682 // The whole function wasn't parsed correctly, just delete this. 4683 L->Destroy(Context); 4684 continue; 4685 } 4686 4687 // Otherwise, the body is valid: we want to stitch the label decl into the 4688 // function somewhere so that it is properly owned and so that the goto 4689 // has a valid target. Do this by creating a new compound stmt with the 4690 // label in it. 4691 4692 // Give the label a sub-statement. 4693 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4694 4695 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4696 cast<CXXTryStmt>(Body)->getTryBlock() : 4697 cast<CompoundStmt>(Body); 4698 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4699 Compound->body_end()); 4700 Elements.push_back(L); 4701 Compound->setStmts(Context, Elements.data(), Elements.size()); 4702 } 4703 4704 if (Body) { 4705 // C++ constructors that have function-try-blocks can't have return 4706 // statements in the handlers of that block. (C++ [except.handle]p14) 4707 // Verify this. 4708 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4709 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4710 4711 // Verify that that gotos and switch cases don't jump into scopes illegally. 4712 // Verify that that gotos and switch cases don't jump into scopes illegally. 4713 if (FunctionNeedsScopeChecking() && 4714 !dcl->isInvalidDecl() && 4715 !hasAnyErrorsInThisFunction()) 4716 DiagnoseInvalidJumps(Body); 4717 4718 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4719 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4720 Destructor->getParent()); 4721 4722 // If any errors have occurred, clear out any temporaries that may have 4723 // been leftover. This ensures that these temporaries won't be picked up for 4724 // deletion in some later function. 4725 if (PP.getDiagnostics().hasErrorOccurred()) 4726 ExprTemporaries.clear(); 4727 else if (!isa<FunctionTemplateDecl>(dcl)) { 4728 // Since the body is valid, issue any analysis-based warnings that are 4729 // enabled. 4730 QualType ResultType; 4731 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4732 ResultType = FD->getResultType(); 4733 } 4734 else { 4735 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4736 ResultType = MD->getResultType(); 4737 } 4738 AnalysisWarnings.IssueWarnings(WP, dcl); 4739 } 4740 4741 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4742 } 4743 4744 if (!IsInstantiation) 4745 PopDeclContext(); 4746 4747 PopFunctionOrBlockScope(); 4748 4749 // If any errors have occurred, clear out any temporaries that may have 4750 // been leftover. This ensures that these temporaries won't be picked up for 4751 // deletion in some later function. 4752 if (getDiagnostics().hasErrorOccurred()) 4753 ExprTemporaries.clear(); 4754 4755 return D; 4756} 4757 4758/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4759/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4760NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4761 IdentifierInfo &II, Scope *S) { 4762 // Before we produce a declaration for an implicitly defined 4763 // function, see whether there was a locally-scoped declaration of 4764 // this name as a function or variable. If so, use that 4765 // (non-visible) declaration, and complain about it. 4766 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4767 = LocallyScopedExternalDecls.find(&II); 4768 if (Pos != LocallyScopedExternalDecls.end()) { 4769 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4770 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4771 return Pos->second; 4772 } 4773 4774 // Extension in C99. Legal in C90, but warn about it. 4775 if (II.getName().startswith("__builtin_")) 4776 Diag(Loc, diag::warn_builtin_unknown) << &II; 4777 else if (getLangOptions().C99) 4778 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4779 else 4780 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4781 4782 // Set a Declarator for the implicit definition: int foo(); 4783 const char *Dummy; 4784 DeclSpec DS; 4785 unsigned DiagID; 4786 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4787 Error = Error; // Silence warning. 4788 assert(!Error && "Error setting up implicit decl!"); 4789 Declarator D(DS, Declarator::BlockContext); 4790 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4791 0, 0, false, SourceLocation(), 4792 false, 0,0,0, Loc, Loc, D), 4793 SourceLocation()); 4794 D.SetIdentifier(&II, Loc); 4795 4796 // Insert this function into translation-unit scope. 4797 4798 DeclContext *PrevDC = CurContext; 4799 CurContext = Context.getTranslationUnitDecl(); 4800 4801 FunctionDecl *FD = 4802 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4803 FD->setImplicit(); 4804 4805 CurContext = PrevDC; 4806 4807 AddKnownFunctionAttributes(FD); 4808 4809 return FD; 4810} 4811 4812/// \brief Adds any function attributes that we know a priori based on 4813/// the declaration of this function. 4814/// 4815/// These attributes can apply both to implicitly-declared builtins 4816/// (like __builtin___printf_chk) or to library-declared functions 4817/// like NSLog or printf. 4818void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4819 if (FD->isInvalidDecl()) 4820 return; 4821 4822 // If this is a built-in function, map its builtin attributes to 4823 // actual attributes. 4824 if (unsigned BuiltinID = FD->getBuiltinID()) { 4825 // Handle printf-formatting attributes. 4826 unsigned FormatIdx; 4827 bool HasVAListArg; 4828 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4829 if (!FD->getAttr<FormatAttr>()) 4830 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4831 HasVAListArg ? 0 : FormatIdx+2)); 4832 } 4833 4834 // Mark const if we don't care about errno and that is the only 4835 // thing preventing the function from being const. This allows 4836 // IRgen to use LLVM intrinsics for such functions. 4837 if (!getLangOptions().MathErrno && 4838 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4839 if (!FD->getAttr<ConstAttr>()) 4840 FD->addAttr(::new (Context) ConstAttr()); 4841 } 4842 4843 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4844 FD->setType(Context.getNoReturnType(FD->getType())); 4845 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4846 FD->addAttr(::new (Context) NoThrowAttr()); 4847 if (Context.BuiltinInfo.isConst(BuiltinID)) 4848 FD->addAttr(::new (Context) ConstAttr()); 4849 } 4850 4851 IdentifierInfo *Name = FD->getIdentifier(); 4852 if (!Name) 4853 return; 4854 if ((!getLangOptions().CPlusPlus && 4855 FD->getDeclContext()->isTranslationUnit()) || 4856 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4857 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4858 LinkageSpecDecl::lang_c)) { 4859 // Okay: this could be a libc/libm/Objective-C function we know 4860 // about. 4861 } else 4862 return; 4863 4864 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4865 // FIXME: NSLog and NSLogv should be target specific 4866 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4867 // FIXME: We known better than our headers. 4868 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4869 } else 4870 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4871 Name->isStr("NSLogv") ? 0 : 2)); 4872 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4873 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4874 // target-specific builtins, perhaps? 4875 if (!FD->getAttr<FormatAttr>()) 4876 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4877 Name->isStr("vasprintf") ? 0 : 3)); 4878 } 4879} 4880 4881TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4882 TypeSourceInfo *TInfo) { 4883 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4884 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4885 4886 if (!TInfo) { 4887 assert(D.isInvalidType() && "no declarator info for valid type"); 4888 TInfo = Context.getTrivialTypeSourceInfo(T); 4889 } 4890 4891 // Scope manipulation handled by caller. 4892 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4893 D.getIdentifierLoc(), 4894 D.getIdentifier(), 4895 TInfo); 4896 4897 if (const TagType *TT = T->getAs<TagType>()) { 4898 TagDecl *TD = TT->getDecl(); 4899 4900 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4901 // keep track of the TypedefDecl. 4902 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4903 TD->setTypedefForAnonDecl(NewTD); 4904 } 4905 4906 if (D.isInvalidType()) 4907 NewTD->setInvalidDecl(); 4908 return NewTD; 4909} 4910 4911 4912/// \brief Determine whether a tag with a given kind is acceptable 4913/// as a redeclaration of the given tag declaration. 4914/// 4915/// \returns true if the new tag kind is acceptable, false otherwise. 4916bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4917 TagTypeKind NewTag, 4918 SourceLocation NewTagLoc, 4919 const IdentifierInfo &Name) { 4920 // C++ [dcl.type.elab]p3: 4921 // The class-key or enum keyword present in the 4922 // elaborated-type-specifier shall agree in kind with the 4923 // declaration to which the name in the elaborated-type-specifier 4924 // refers. This rule also applies to the form of 4925 // elaborated-type-specifier that declares a class-name or 4926 // friend class since it can be construed as referring to the 4927 // definition of the class. Thus, in any 4928 // elaborated-type-specifier, the enum keyword shall be used to 4929 // refer to an enumeration (7.2), the union class-key shall be 4930 // used to refer to a union (clause 9), and either the class or 4931 // struct class-key shall be used to refer to a class (clause 9) 4932 // declared using the class or struct class-key. 4933 TagTypeKind OldTag = Previous->getTagKind(); 4934 if (OldTag == NewTag) 4935 return true; 4936 4937 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 4938 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 4939 // Warn about the struct/class tag mismatch. 4940 bool isTemplate = false; 4941 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4942 isTemplate = Record->getDescribedClassTemplate(); 4943 4944 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4945 << (NewTag == TTK_Class) 4946 << isTemplate << &Name 4947 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 4948 OldTag == TTK_Class? "class" : "struct"); 4949 Diag(Previous->getLocation(), diag::note_previous_use); 4950 return true; 4951 } 4952 return false; 4953} 4954 4955/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4956/// former case, Name will be non-null. In the later case, Name will be null. 4957/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4958/// reference/declaration/definition of a tag. 4959Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4960 SourceLocation KWLoc, CXXScopeSpec &SS, 4961 IdentifierInfo *Name, SourceLocation NameLoc, 4962 AttributeList *Attr, AccessSpecifier AS, 4963 MultiTemplateParamsArg TemplateParameterLists, 4964 bool &OwnedDecl, bool &IsDependent) { 4965 // If this is not a definition, it must have a name. 4966 assert((Name != 0 || TUK == TUK_Definition) && 4967 "Nameless record must be a definition!"); 4968 4969 OwnedDecl = false; 4970 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 4971 4972 // FIXME: Check explicit specializations more carefully. 4973 bool isExplicitSpecialization = false; 4974 if (TUK != TUK_Reference) { 4975 if (TemplateParameterList *TemplateParams 4976 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4977 (TemplateParameterList**)TemplateParameterLists.get(), 4978 TemplateParameterLists.size(), 4979 TUK == TUK_Friend, 4980 isExplicitSpecialization)) { 4981 if (TemplateParams->size() > 0) { 4982 // This is a declaration or definition of a class template (which may 4983 // be a member of another template). 4984 OwnedDecl = false; 4985 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4986 SS, Name, NameLoc, Attr, 4987 TemplateParams, 4988 AS); 4989 TemplateParameterLists.release(); 4990 return Result.get(); 4991 } else { 4992 // The "template<>" header is extraneous. 4993 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4994 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 4995 isExplicitSpecialization = true; 4996 } 4997 } 4998 4999 TemplateParameterLists.release(); 5000 } 5001 5002 DeclContext *SearchDC = CurContext; 5003 DeclContext *DC = CurContext; 5004 bool isStdBadAlloc = false; 5005 bool Invalid = false; 5006 5007 RedeclarationKind Redecl = ForRedeclaration; 5008 if (TUK == TUK_Friend || TUK == TUK_Reference) 5009 Redecl = NotForRedeclaration; 5010 5011 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5012 5013 if (Name && SS.isNotEmpty()) { 5014 // We have a nested-name tag ('struct foo::bar'). 5015 5016 // Check for invalid 'foo::'. 5017 if (SS.isInvalid()) { 5018 Name = 0; 5019 goto CreateNewDecl; 5020 } 5021 5022 // If this is a friend or a reference to a class in a dependent 5023 // context, don't try to make a decl for it. 5024 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5025 DC = computeDeclContext(SS, false); 5026 if (!DC) { 5027 IsDependent = true; 5028 return DeclPtrTy(); 5029 } 5030 } else { 5031 DC = computeDeclContext(SS, true); 5032 if (!DC) { 5033 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5034 << SS.getRange(); 5035 return DeclPtrTy(); 5036 } 5037 } 5038 5039 if (RequireCompleteDeclContext(SS, DC)) 5040 return DeclPtrTy::make((Decl *)0); 5041 5042 SearchDC = DC; 5043 // Look-up name inside 'foo::'. 5044 LookupQualifiedName(Previous, DC); 5045 5046 if (Previous.isAmbiguous()) 5047 return DeclPtrTy(); 5048 5049 if (Previous.empty()) { 5050 // Name lookup did not find anything. However, if the 5051 // nested-name-specifier refers to the current instantiation, 5052 // and that current instantiation has any dependent base 5053 // classes, we might find something at instantiation time: treat 5054 // this as a dependent elaborated-type-specifier. 5055 if (Previous.wasNotFoundInCurrentInstantiation()) { 5056 IsDependent = true; 5057 return DeclPtrTy(); 5058 } 5059 5060 // A tag 'foo::bar' must already exist. 5061 Diag(NameLoc, diag::err_not_tag_in_scope) 5062 << Kind << Name << DC << SS.getRange(); 5063 Name = 0; 5064 Invalid = true; 5065 goto CreateNewDecl; 5066 } 5067 } else if (Name) { 5068 // If this is a named struct, check to see if there was a previous forward 5069 // declaration or definition. 5070 // FIXME: We're looking into outer scopes here, even when we 5071 // shouldn't be. Doing so can result in ambiguities that we 5072 // shouldn't be diagnosing. 5073 LookupName(Previous, S); 5074 5075 // Note: there used to be some attempt at recovery here. 5076 if (Previous.isAmbiguous()) 5077 return DeclPtrTy(); 5078 5079 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5080 // FIXME: This makes sure that we ignore the contexts associated 5081 // with C structs, unions, and enums when looking for a matching 5082 // tag declaration or definition. See the similar lookup tweak 5083 // in Sema::LookupName; is there a better way to deal with this? 5084 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5085 SearchDC = SearchDC->getParent(); 5086 } 5087 } 5088 5089 if (Previous.isSingleResult() && 5090 Previous.getFoundDecl()->isTemplateParameter()) { 5091 // Maybe we will complain about the shadowed template parameter. 5092 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5093 // Just pretend that we didn't see the previous declaration. 5094 Previous.clear(); 5095 } 5096 5097 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5098 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 5099 // This is a declaration of or a reference to "std::bad_alloc". 5100 isStdBadAlloc = true; 5101 5102 if (Previous.empty() && StdBadAlloc) { 5103 // std::bad_alloc has been implicitly declared (but made invisible to 5104 // name lookup). Fill in this implicit declaration as the previous 5105 // declaration, so that the declarations get chained appropriately. 5106 Previous.addDecl(StdBadAlloc); 5107 } 5108 } 5109 5110 // If we didn't find a previous declaration, and this is a reference 5111 // (or friend reference), move to the correct scope. In C++, we 5112 // also need to do a redeclaration lookup there, just in case 5113 // there's a shadow friend decl. 5114 if (Name && Previous.empty() && 5115 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5116 if (Invalid) goto CreateNewDecl; 5117 assert(SS.isEmpty()); 5118 5119 if (TUK == TUK_Reference) { 5120 // C++ [basic.scope.pdecl]p5: 5121 // -- for an elaborated-type-specifier of the form 5122 // 5123 // class-key identifier 5124 // 5125 // if the elaborated-type-specifier is used in the 5126 // decl-specifier-seq or parameter-declaration-clause of a 5127 // function defined in namespace scope, the identifier is 5128 // declared as a class-name in the namespace that contains 5129 // the declaration; otherwise, except as a friend 5130 // declaration, the identifier is declared in the smallest 5131 // non-class, non-function-prototype scope that contains the 5132 // declaration. 5133 // 5134 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5135 // C structs and unions. 5136 // 5137 // It is an error in C++ to declare (rather than define) an enum 5138 // type, including via an elaborated type specifier. We'll 5139 // diagnose that later; for now, declare the enum in the same 5140 // scope as we would have picked for any other tag type. 5141 // 5142 // GNU C also supports this behavior as part of its incomplete 5143 // enum types extension, while GNU C++ does not. 5144 // 5145 // Find the context where we'll be declaring the tag. 5146 // FIXME: We would like to maintain the current DeclContext as the 5147 // lexical context, 5148 while (SearchDC->isRecord()) 5149 SearchDC = SearchDC->getParent(); 5150 5151 // Find the scope where we'll be declaring the tag. 5152 while (S->isClassScope() || 5153 (getLangOptions().CPlusPlus && 5154 S->isFunctionPrototypeScope()) || 5155 ((S->getFlags() & Scope::DeclScope) == 0) || 5156 (S->getEntity() && 5157 ((DeclContext *)S->getEntity())->isTransparentContext())) 5158 S = S->getParent(); 5159 } else { 5160 assert(TUK == TUK_Friend); 5161 // C++ [namespace.memdef]p3: 5162 // If a friend declaration in a non-local class first declares a 5163 // class or function, the friend class or function is a member of 5164 // the innermost enclosing namespace. 5165 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5166 } 5167 5168 // In C++, we need to do a redeclaration lookup to properly 5169 // diagnose some problems. 5170 if (getLangOptions().CPlusPlus) { 5171 Previous.setRedeclarationKind(ForRedeclaration); 5172 LookupQualifiedName(Previous, SearchDC); 5173 } 5174 } 5175 5176 if (!Previous.empty()) { 5177 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5178 5179 // It's okay to have a tag decl in the same scope as a typedef 5180 // which hides a tag decl in the same scope. Finding this 5181 // insanity with a redeclaration lookup can only actually happen 5182 // in C++. 5183 // 5184 // This is also okay for elaborated-type-specifiers, which is 5185 // technically forbidden by the current standard but which is 5186 // okay according to the likely resolution of an open issue; 5187 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5188 if (getLangOptions().CPlusPlus) { 5189 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5190 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5191 TagDecl *Tag = TT->getDecl(); 5192 if (Tag->getDeclName() == Name && 5193 Tag->getDeclContext()->getLookupContext() 5194 ->Equals(TD->getDeclContext()->getLookupContext())) { 5195 PrevDecl = Tag; 5196 Previous.clear(); 5197 Previous.addDecl(Tag); 5198 } 5199 } 5200 } 5201 } 5202 5203 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5204 // If this is a use of a previous tag, or if the tag is already declared 5205 // in the same scope (so that the definition/declaration completes or 5206 // rementions the tag), reuse the decl. 5207 if (TUK == TUK_Reference || TUK == TUK_Friend || 5208 isDeclInScope(PrevDecl, SearchDC, S)) { 5209 // Make sure that this wasn't declared as an enum and now used as a 5210 // struct or something similar. 5211 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5212 bool SafeToContinue 5213 = (PrevTagDecl->getTagKind() != TTK_Enum && 5214 Kind != TTK_Enum); 5215 if (SafeToContinue) 5216 Diag(KWLoc, diag::err_use_with_wrong_tag) 5217 << Name 5218 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5219 PrevTagDecl->getKindName()); 5220 else 5221 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5222 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5223 5224 if (SafeToContinue) 5225 Kind = PrevTagDecl->getTagKind(); 5226 else { 5227 // Recover by making this an anonymous redefinition. 5228 Name = 0; 5229 Previous.clear(); 5230 Invalid = true; 5231 } 5232 } 5233 5234 if (!Invalid) { 5235 // If this is a use, just return the declaration we found. 5236 5237 // FIXME: In the future, return a variant or some other clue 5238 // for the consumer of this Decl to know it doesn't own it. 5239 // For our current ASTs this shouldn't be a problem, but will 5240 // need to be changed with DeclGroups. 5241 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5242 TUK == TUK_Friend) 5243 return DeclPtrTy::make(PrevTagDecl); 5244 5245 // Diagnose attempts to redefine a tag. 5246 if (TUK == TUK_Definition) { 5247 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5248 // If we're defining a specialization and the previous definition 5249 // is from an implicit instantiation, don't emit an error 5250 // here; we'll catch this in the general case below. 5251 if (!isExplicitSpecialization || 5252 !isa<CXXRecordDecl>(Def) || 5253 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5254 == TSK_ExplicitSpecialization) { 5255 Diag(NameLoc, diag::err_redefinition) << Name; 5256 Diag(Def->getLocation(), diag::note_previous_definition); 5257 // If this is a redefinition, recover by making this 5258 // struct be anonymous, which will make any later 5259 // references get the previous definition. 5260 Name = 0; 5261 Previous.clear(); 5262 Invalid = true; 5263 } 5264 } else { 5265 // If the type is currently being defined, complain 5266 // about a nested redefinition. 5267 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5268 if (Tag->isBeingDefined()) { 5269 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5270 Diag(PrevTagDecl->getLocation(), 5271 diag::note_previous_definition); 5272 Name = 0; 5273 Previous.clear(); 5274 Invalid = true; 5275 } 5276 } 5277 5278 // Okay, this is definition of a previously declared or referenced 5279 // tag PrevDecl. We're going to create a new Decl for it. 5280 } 5281 } 5282 // If we get here we have (another) forward declaration or we 5283 // have a definition. Just create a new decl. 5284 5285 } else { 5286 // If we get here, this is a definition of a new tag type in a nested 5287 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5288 // new decl/type. We set PrevDecl to NULL so that the entities 5289 // have distinct types. 5290 Previous.clear(); 5291 } 5292 // If we get here, we're going to create a new Decl. If PrevDecl 5293 // is non-NULL, it's a definition of the tag declared by 5294 // PrevDecl. If it's NULL, we have a new definition. 5295 5296 5297 // Otherwise, PrevDecl is not a tag, but was found with tag 5298 // lookup. This is only actually possible in C++, where a few 5299 // things like templates still live in the tag namespace. 5300 } else { 5301 assert(getLangOptions().CPlusPlus); 5302 5303 // Use a better diagnostic if an elaborated-type-specifier 5304 // found the wrong kind of type on the first 5305 // (non-redeclaration) lookup. 5306 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5307 !Previous.isForRedeclaration()) { 5308 unsigned Kind = 0; 5309 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5310 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5311 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5312 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5313 Invalid = true; 5314 5315 // Otherwise, only diagnose if the declaration is in scope. 5316 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5317 // do nothing 5318 5319 // Diagnose implicit declarations introduced by elaborated types. 5320 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5321 unsigned Kind = 0; 5322 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5323 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5324 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5325 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5326 Invalid = true; 5327 5328 // Otherwise it's a declaration. Call out a particularly common 5329 // case here. 5330 } else if (isa<TypedefDecl>(PrevDecl)) { 5331 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5332 << Name 5333 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5334 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5335 Invalid = true; 5336 5337 // Otherwise, diagnose. 5338 } else { 5339 // The tag name clashes with something else in the target scope, 5340 // issue an error and recover by making this tag be anonymous. 5341 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5342 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5343 Name = 0; 5344 Invalid = true; 5345 } 5346 5347 // The existing declaration isn't relevant to us; we're in a 5348 // new scope, so clear out the previous declaration. 5349 Previous.clear(); 5350 } 5351 } 5352 5353CreateNewDecl: 5354 5355 TagDecl *PrevDecl = 0; 5356 if (Previous.isSingleResult()) 5357 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5358 5359 // If there is an identifier, use the location of the identifier as the 5360 // location of the decl, otherwise use the location of the struct/union 5361 // keyword. 5362 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5363 5364 // Otherwise, create a new declaration. If there is a previous 5365 // declaration of the same entity, the two will be linked via 5366 // PrevDecl. 5367 TagDecl *New; 5368 5369 if (Kind == TTK_Enum) { 5370 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5371 // enum X { A, B, C } D; D should chain to X. 5372 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5373 cast_or_null<EnumDecl>(PrevDecl)); 5374 // If this is an undefined enum, warn. 5375 if (TUK != TUK_Definition && !Invalid) { 5376 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5377 : diag::ext_forward_ref_enum; 5378 Diag(Loc, DK); 5379 } 5380 } else { 5381 // struct/union/class 5382 5383 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5384 // struct X { int A; } D; D should chain to X. 5385 if (getLangOptions().CPlusPlus) { 5386 // FIXME: Look for a way to use RecordDecl for simple structs. 5387 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5388 cast_or_null<CXXRecordDecl>(PrevDecl)); 5389 5390 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5391 StdBadAlloc = cast<CXXRecordDecl>(New); 5392 } else 5393 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5394 cast_or_null<RecordDecl>(PrevDecl)); 5395 } 5396 5397 // Maybe add qualifier info. 5398 if (SS.isNotEmpty()) { 5399 if (SS.isSet()) { 5400 NestedNameSpecifier *NNS 5401 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5402 New->setQualifierInfo(NNS, SS.getRange()); 5403 } 5404 else 5405 Invalid = true; 5406 } 5407 5408 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5409 // Add alignment attributes if necessary; these attributes are checked when 5410 // the ASTContext lays out the structure. 5411 // 5412 // It is important for implementing the correct semantics that this 5413 // happen here (in act on tag decl). The #pragma pack stack is 5414 // maintained as a result of parser callbacks which can occur at 5415 // many points during the parsing of a struct declaration (because 5416 // the #pragma tokens are effectively skipped over during the 5417 // parsing of the struct). 5418 AddAlignmentAttributesForRecord(RD); 5419 } 5420 5421 // If this is a specialization of a member class (of a class template), 5422 // check the specialization. 5423 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5424 Invalid = true; 5425 5426 if (Invalid) 5427 New->setInvalidDecl(); 5428 5429 if (Attr) 5430 ProcessDeclAttributeList(S, New, Attr); 5431 5432 // If we're declaring or defining a tag in function prototype scope 5433 // in C, note that this type can only be used within the function. 5434 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5435 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5436 5437 // Set the lexical context. If the tag has a C++ scope specifier, the 5438 // lexical context will be different from the semantic context. 5439 New->setLexicalDeclContext(CurContext); 5440 5441 // Mark this as a friend decl if applicable. 5442 if (TUK == TUK_Friend) 5443 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5444 5445 // Set the access specifier. 5446 if (!Invalid && SearchDC->isRecord()) 5447 SetMemberAccessSpecifier(New, PrevDecl, AS); 5448 5449 if (TUK == TUK_Definition) 5450 New->startDefinition(); 5451 5452 // If this has an identifier, add it to the scope stack. 5453 if (TUK == TUK_Friend) { 5454 // We might be replacing an existing declaration in the lookup tables; 5455 // if so, borrow its access specifier. 5456 if (PrevDecl) 5457 New->setAccess(PrevDecl->getAccess()); 5458 5459 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5460 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5461 if (Name) // can be null along some error paths 5462 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5463 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5464 } else if (Name) { 5465 S = getNonFieldDeclScope(S); 5466 PushOnScopeChains(New, S); 5467 } else { 5468 CurContext->addDecl(New); 5469 } 5470 5471 // If this is the C FILE type, notify the AST context. 5472 if (IdentifierInfo *II = New->getIdentifier()) 5473 if (!New->isInvalidDecl() && 5474 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5475 II->isStr("FILE")) 5476 Context.setFILEDecl(New); 5477 5478 OwnedDecl = true; 5479 return DeclPtrTy::make(New); 5480} 5481 5482void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5483 AdjustDeclIfTemplate(TagD); 5484 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5485 5486 // Enter the tag context. 5487 PushDeclContext(S, Tag); 5488} 5489 5490void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5491 SourceLocation LBraceLoc) { 5492 AdjustDeclIfTemplate(TagD); 5493 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5494 5495 FieldCollector->StartClass(); 5496 5497 if (!Record->getIdentifier()) 5498 return; 5499 5500 // C++ [class]p2: 5501 // [...] The class-name is also inserted into the scope of the 5502 // class itself; this is known as the injected-class-name. For 5503 // purposes of access checking, the injected-class-name is treated 5504 // as if it were a public member name. 5505 CXXRecordDecl *InjectedClassName 5506 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5507 CurContext, Record->getLocation(), 5508 Record->getIdentifier(), 5509 Record->getTagKeywordLoc(), 5510 Record); 5511 InjectedClassName->setImplicit(); 5512 InjectedClassName->setAccess(AS_public); 5513 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5514 InjectedClassName->setDescribedClassTemplate(Template); 5515 PushOnScopeChains(InjectedClassName, S); 5516 assert(InjectedClassName->isInjectedClassName() && 5517 "Broken injected-class-name"); 5518} 5519 5520void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5521 SourceLocation RBraceLoc) { 5522 AdjustDeclIfTemplate(TagD); 5523 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5524 Tag->setRBraceLoc(RBraceLoc); 5525 5526 if (isa<CXXRecordDecl>(Tag)) 5527 FieldCollector->FinishClass(); 5528 5529 // Exit this scope of this tag's definition. 5530 PopDeclContext(); 5531 5532 // Notify the consumer that we've defined a tag. 5533 Consumer.HandleTagDeclDefinition(Tag); 5534} 5535 5536void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5537 AdjustDeclIfTemplate(TagD); 5538 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5539 Tag->setInvalidDecl(); 5540 5541 // We're undoing ActOnTagStartDefinition here, not 5542 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5543 // the FieldCollector. 5544 5545 PopDeclContext(); 5546} 5547 5548// Note that FieldName may be null for anonymous bitfields. 5549bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5550 QualType FieldTy, const Expr *BitWidth, 5551 bool *ZeroWidth) { 5552 // Default to true; that shouldn't confuse checks for emptiness 5553 if (ZeroWidth) 5554 *ZeroWidth = true; 5555 5556 // C99 6.7.2.1p4 - verify the field type. 5557 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5558 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5559 // Handle incomplete types with specific error. 5560 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5561 return true; 5562 if (FieldName) 5563 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5564 << FieldName << FieldTy << BitWidth->getSourceRange(); 5565 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5566 << FieldTy << BitWidth->getSourceRange(); 5567 } 5568 5569 // If the bit-width is type- or value-dependent, don't try to check 5570 // it now. 5571 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5572 return false; 5573 5574 llvm::APSInt Value; 5575 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5576 return true; 5577 5578 if (Value != 0 && ZeroWidth) 5579 *ZeroWidth = false; 5580 5581 // Zero-width bitfield is ok for anonymous field. 5582 if (Value == 0 && FieldName) 5583 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5584 5585 if (Value.isSigned() && Value.isNegative()) { 5586 if (FieldName) 5587 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5588 << FieldName << Value.toString(10); 5589 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5590 << Value.toString(10); 5591 } 5592 5593 if (!FieldTy->isDependentType()) { 5594 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5595 if (Value.getZExtValue() > TypeSize) { 5596 if (!getLangOptions().CPlusPlus) { 5597 if (FieldName) 5598 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5599 << FieldName << (unsigned)Value.getZExtValue() 5600 << (unsigned)TypeSize; 5601 5602 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5603 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5604 } 5605 5606 if (FieldName) 5607 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5608 << FieldName << (unsigned)Value.getZExtValue() 5609 << (unsigned)TypeSize; 5610 else 5611 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5612 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5613 } 5614 } 5615 5616 return false; 5617} 5618 5619/// ActOnField - Each field of a struct/union/class is passed into this in order 5620/// to create a FieldDecl object for it. 5621Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5622 SourceLocation DeclStart, 5623 Declarator &D, ExprTy *BitfieldWidth) { 5624 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5625 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5626 AS_public); 5627 return DeclPtrTy::make(Res); 5628} 5629 5630/// HandleField - Analyze a field of a C struct or a C++ data member. 5631/// 5632FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5633 SourceLocation DeclStart, 5634 Declarator &D, Expr *BitWidth, 5635 AccessSpecifier AS) { 5636 IdentifierInfo *II = D.getIdentifier(); 5637 SourceLocation Loc = DeclStart; 5638 if (II) Loc = D.getIdentifierLoc(); 5639 5640 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5641 QualType T = TInfo->getType(); 5642 if (getLangOptions().CPlusPlus) 5643 CheckExtraCXXDefaultArguments(D); 5644 5645 DiagnoseFunctionSpecifiers(D); 5646 5647 if (D.getDeclSpec().isThreadSpecified()) 5648 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5649 5650 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5651 ForRedeclaration); 5652 5653 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5654 // Maybe we will complain about the shadowed template parameter. 5655 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5656 // Just pretend that we didn't see the previous declaration. 5657 PrevDecl = 0; 5658 } 5659 5660 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5661 PrevDecl = 0; 5662 5663 bool Mutable 5664 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5665 SourceLocation TSSL = D.getSourceRange().getBegin(); 5666 FieldDecl *NewFD 5667 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5668 AS, PrevDecl, &D); 5669 5670 if (NewFD->isInvalidDecl()) 5671 Record->setInvalidDecl(); 5672 5673 if (NewFD->isInvalidDecl() && PrevDecl) { 5674 // Don't introduce NewFD into scope; there's already something 5675 // with the same name in the same scope. 5676 } else if (II) { 5677 PushOnScopeChains(NewFD, S); 5678 } else 5679 Record->addDecl(NewFD); 5680 5681 return NewFD; 5682} 5683 5684/// \brief Build a new FieldDecl and check its well-formedness. 5685/// 5686/// This routine builds a new FieldDecl given the fields name, type, 5687/// record, etc. \p PrevDecl should refer to any previous declaration 5688/// with the same name and in the same scope as the field to be 5689/// created. 5690/// 5691/// \returns a new FieldDecl. 5692/// 5693/// \todo The Declarator argument is a hack. It will be removed once 5694FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5695 TypeSourceInfo *TInfo, 5696 RecordDecl *Record, SourceLocation Loc, 5697 bool Mutable, Expr *BitWidth, 5698 SourceLocation TSSL, 5699 AccessSpecifier AS, NamedDecl *PrevDecl, 5700 Declarator *D) { 5701 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5702 bool InvalidDecl = false; 5703 if (D) InvalidDecl = D->isInvalidType(); 5704 5705 // If we receive a broken type, recover by assuming 'int' and 5706 // marking this declaration as invalid. 5707 if (T.isNull()) { 5708 InvalidDecl = true; 5709 T = Context.IntTy; 5710 } 5711 5712 QualType EltTy = Context.getBaseElementType(T); 5713 if (!EltTy->isDependentType() && 5714 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5715 InvalidDecl = true; 5716 5717 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5718 // than a variably modified type. 5719 if (!InvalidDecl && T->isVariablyModifiedType()) { 5720 bool SizeIsNegative; 5721 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5722 SizeIsNegative); 5723 if (!FixedTy.isNull()) { 5724 Diag(Loc, diag::warn_illegal_constant_array_size); 5725 T = FixedTy; 5726 } else { 5727 if (SizeIsNegative) 5728 Diag(Loc, diag::err_typecheck_negative_array_size); 5729 else 5730 Diag(Loc, diag::err_typecheck_field_variable_size); 5731 InvalidDecl = true; 5732 } 5733 } 5734 5735 // Fields can not have abstract class types 5736 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5737 diag::err_abstract_type_in_decl, 5738 AbstractFieldType)) 5739 InvalidDecl = true; 5740 5741 bool ZeroWidth = false; 5742 // If this is declared as a bit-field, check the bit-field. 5743 if (!InvalidDecl && BitWidth && 5744 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5745 InvalidDecl = true; 5746 DeleteExpr(BitWidth); 5747 BitWidth = 0; 5748 ZeroWidth = false; 5749 } 5750 5751 // Check that 'mutable' is consistent with the type of the declaration. 5752 if (!InvalidDecl && Mutable) { 5753 unsigned DiagID = 0; 5754 if (T->isReferenceType()) 5755 DiagID = diag::err_mutable_reference; 5756 else if (T.isConstQualified()) 5757 DiagID = diag::err_mutable_const; 5758 5759 if (DiagID) { 5760 SourceLocation ErrLoc = Loc; 5761 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 5762 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 5763 Diag(ErrLoc, DiagID); 5764 Mutable = false; 5765 InvalidDecl = true; 5766 } 5767 } 5768 5769 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5770 BitWidth, Mutable); 5771 if (InvalidDecl) 5772 NewFD->setInvalidDecl(); 5773 5774 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5775 Diag(Loc, diag::err_duplicate_member) << II; 5776 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5777 NewFD->setInvalidDecl(); 5778 } 5779 5780 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5781 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5782 5783 if (!T->isPODType()) 5784 CXXRecord->setPOD(false); 5785 if (!ZeroWidth) 5786 CXXRecord->setEmpty(false); 5787 5788 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5789 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5790 5791 if (!RDecl->hasTrivialConstructor()) 5792 CXXRecord->setHasTrivialConstructor(false); 5793 if (!RDecl->hasTrivialCopyConstructor()) 5794 CXXRecord->setHasTrivialCopyConstructor(false); 5795 if (!RDecl->hasTrivialCopyAssignment()) 5796 CXXRecord->setHasTrivialCopyAssignment(false); 5797 if (!RDecl->hasTrivialDestructor()) 5798 CXXRecord->setHasTrivialDestructor(false); 5799 5800 // C++ 9.5p1: An object of a class with a non-trivial 5801 // constructor, a non-trivial copy constructor, a non-trivial 5802 // destructor, or a non-trivial copy assignment operator 5803 // cannot be a member of a union, nor can an array of such 5804 // objects. 5805 // TODO: C++0x alters this restriction significantly. 5806 if (Record->isUnion()) { 5807 // We check for copy constructors before constructors 5808 // because otherwise we'll never get complaints about 5809 // copy constructors. 5810 5811 CXXSpecialMember member = CXXInvalid; 5812 if (!RDecl->hasTrivialCopyConstructor()) 5813 member = CXXCopyConstructor; 5814 else if (!RDecl->hasTrivialConstructor()) 5815 member = CXXConstructor; 5816 else if (!RDecl->hasTrivialCopyAssignment()) 5817 member = CXXCopyAssignment; 5818 else if (!RDecl->hasTrivialDestructor()) 5819 member = CXXDestructor; 5820 5821 if (member != CXXInvalid) { 5822 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5823 DiagnoseNontrivial(RT, member); 5824 NewFD->setInvalidDecl(); 5825 } 5826 } 5827 } 5828 } 5829 5830 // FIXME: We need to pass in the attributes given an AST 5831 // representation, not a parser representation. 5832 if (D) 5833 // FIXME: What to pass instead of TUScope? 5834 ProcessDeclAttributes(TUScope, NewFD, *D); 5835 5836 if (T.isObjCGCWeak()) 5837 Diag(Loc, diag::warn_attribute_weak_on_field); 5838 5839 NewFD->setAccess(AS); 5840 5841 // C++ [dcl.init.aggr]p1: 5842 // An aggregate is an array or a class (clause 9) with [...] no 5843 // private or protected non-static data members (clause 11). 5844 // A POD must be an aggregate. 5845 if (getLangOptions().CPlusPlus && 5846 (AS == AS_private || AS == AS_protected)) { 5847 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5848 CXXRecord->setAggregate(false); 5849 CXXRecord->setPOD(false); 5850 } 5851 5852 return NewFD; 5853} 5854 5855/// DiagnoseNontrivial - Given that a class has a non-trivial 5856/// special member, figure out why. 5857void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5858 QualType QT(T, 0U); 5859 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5860 5861 // Check whether the member was user-declared. 5862 switch (member) { 5863 case CXXInvalid: 5864 break; 5865 5866 case CXXConstructor: 5867 if (RD->hasUserDeclaredConstructor()) { 5868 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5869 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5870 const FunctionDecl *body = 0; 5871 ci->getBody(body); 5872 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5873 SourceLocation CtorLoc = ci->getLocation(); 5874 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5875 return; 5876 } 5877 } 5878 5879 assert(0 && "found no user-declared constructors"); 5880 return; 5881 } 5882 break; 5883 5884 case CXXCopyConstructor: 5885 if (RD->hasUserDeclaredCopyConstructor()) { 5886 SourceLocation CtorLoc = 5887 RD->getCopyConstructor(Context, 0)->getLocation(); 5888 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5889 return; 5890 } 5891 break; 5892 5893 case CXXCopyAssignment: 5894 if (RD->hasUserDeclaredCopyAssignment()) { 5895 // FIXME: this should use the location of the copy 5896 // assignment, not the type. 5897 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5898 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5899 return; 5900 } 5901 break; 5902 5903 case CXXDestructor: 5904 if (RD->hasUserDeclaredDestructor()) { 5905 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5906 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5907 return; 5908 } 5909 break; 5910 } 5911 5912 typedef CXXRecordDecl::base_class_iterator base_iter; 5913 5914 // Virtual bases and members inhibit trivial copying/construction, 5915 // but not trivial destruction. 5916 if (member != CXXDestructor) { 5917 // Check for virtual bases. vbases includes indirect virtual bases, 5918 // so we just iterate through the direct bases. 5919 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5920 if (bi->isVirtual()) { 5921 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5922 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5923 return; 5924 } 5925 5926 // Check for virtual methods. 5927 typedef CXXRecordDecl::method_iterator meth_iter; 5928 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5929 ++mi) { 5930 if (mi->isVirtual()) { 5931 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5932 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5933 return; 5934 } 5935 } 5936 } 5937 5938 bool (CXXRecordDecl::*hasTrivial)() const; 5939 switch (member) { 5940 case CXXConstructor: 5941 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5942 case CXXCopyConstructor: 5943 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5944 case CXXCopyAssignment: 5945 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5946 case CXXDestructor: 5947 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5948 default: 5949 assert(0 && "unexpected special member"); return; 5950 } 5951 5952 // Check for nontrivial bases (and recurse). 5953 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5954 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5955 assert(BaseRT && "Don't know how to handle dependent bases"); 5956 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5957 if (!(BaseRecTy->*hasTrivial)()) { 5958 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5959 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5960 DiagnoseNontrivial(BaseRT, member); 5961 return; 5962 } 5963 } 5964 5965 // Check for nontrivial members (and recurse). 5966 typedef RecordDecl::field_iterator field_iter; 5967 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5968 ++fi) { 5969 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5970 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5971 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5972 5973 if (!(EltRD->*hasTrivial)()) { 5974 SourceLocation FLoc = (*fi)->getLocation(); 5975 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5976 DiagnoseNontrivial(EltRT, member); 5977 return; 5978 } 5979 } 5980 } 5981 5982 assert(0 && "found no explanation for non-trivial member"); 5983} 5984 5985/// TranslateIvarVisibility - Translate visibility from a token ID to an 5986/// AST enum value. 5987static ObjCIvarDecl::AccessControl 5988TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5989 switch (ivarVisibility) { 5990 default: assert(0 && "Unknown visitibility kind"); 5991 case tok::objc_private: return ObjCIvarDecl::Private; 5992 case tok::objc_public: return ObjCIvarDecl::Public; 5993 case tok::objc_protected: return ObjCIvarDecl::Protected; 5994 case tok::objc_package: return ObjCIvarDecl::Package; 5995 } 5996} 5997 5998/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5999/// in order to create an IvarDecl object for it. 6000Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6001 SourceLocation DeclStart, 6002 DeclPtrTy IntfDecl, 6003 Declarator &D, ExprTy *BitfieldWidth, 6004 tok::ObjCKeywordKind Visibility) { 6005 6006 IdentifierInfo *II = D.getIdentifier(); 6007 Expr *BitWidth = (Expr*)BitfieldWidth; 6008 SourceLocation Loc = DeclStart; 6009 if (II) Loc = D.getIdentifierLoc(); 6010 6011 // FIXME: Unnamed fields can be handled in various different ways, for 6012 // example, unnamed unions inject all members into the struct namespace! 6013 6014 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6015 QualType T = TInfo->getType(); 6016 6017 if (BitWidth) { 6018 // 6.7.2.1p3, 6.7.2.1p4 6019 if (VerifyBitField(Loc, II, T, BitWidth)) { 6020 D.setInvalidType(); 6021 DeleteExpr(BitWidth); 6022 BitWidth = 0; 6023 } 6024 } else { 6025 // Not a bitfield. 6026 6027 // validate II. 6028 6029 } 6030 if (T->isReferenceType()) { 6031 Diag(Loc, diag::err_ivar_reference_type); 6032 D.setInvalidType(); 6033 } 6034 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6035 // than a variably modified type. 6036 else if (T->isVariablyModifiedType()) { 6037 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6038 D.setInvalidType(); 6039 } 6040 6041 // Get the visibility (access control) for this ivar. 6042 ObjCIvarDecl::AccessControl ac = 6043 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6044 : ObjCIvarDecl::None; 6045 // Must set ivar's DeclContext to its enclosing interface. 6046 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6047 ObjCContainerDecl *EnclosingContext; 6048 if (ObjCImplementationDecl *IMPDecl = 6049 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6050 // Case of ivar declared in an implementation. Context is that of its class. 6051 EnclosingContext = IMPDecl->getClassInterface(); 6052 assert(EnclosingContext && "Implementation has no class interface!"); 6053 } else { 6054 if (ObjCCategoryDecl *CDecl = 6055 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6056 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6057 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6058 return DeclPtrTy(); 6059 } 6060 } 6061 EnclosingContext = EnclosingDecl; 6062 } 6063 6064 // Construct the decl. 6065 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6066 EnclosingContext, Loc, II, T, 6067 TInfo, ac, (Expr *)BitfieldWidth); 6068 6069 if (II) { 6070 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6071 ForRedeclaration); 6072 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6073 && !isa<TagDecl>(PrevDecl)) { 6074 Diag(Loc, diag::err_duplicate_member) << II; 6075 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6076 NewID->setInvalidDecl(); 6077 } 6078 } 6079 6080 // Process attributes attached to the ivar. 6081 ProcessDeclAttributes(S, NewID, D); 6082 6083 if (D.isInvalidType()) 6084 NewID->setInvalidDecl(); 6085 6086 if (II) { 6087 // FIXME: When interfaces are DeclContexts, we'll need to add 6088 // these to the interface. 6089 S->AddDecl(DeclPtrTy::make(NewID)); 6090 IdResolver.AddDecl(NewID); 6091 } 6092 6093 return DeclPtrTy::make(NewID); 6094} 6095 6096void Sema::ActOnFields(Scope* S, 6097 SourceLocation RecLoc, DeclPtrTy RecDecl, 6098 DeclPtrTy *Fields, unsigned NumFields, 6099 SourceLocation LBrac, SourceLocation RBrac, 6100 AttributeList *Attr) { 6101 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6102 assert(EnclosingDecl && "missing record or interface decl"); 6103 6104 // If the decl this is being inserted into is invalid, then it may be a 6105 // redeclaration or some other bogus case. Don't try to add fields to it. 6106 if (EnclosingDecl->isInvalidDecl()) { 6107 // FIXME: Deallocate fields? 6108 return; 6109 } 6110 6111 6112 // Verify that all the fields are okay. 6113 unsigned NumNamedMembers = 0; 6114 llvm::SmallVector<FieldDecl*, 32> RecFields; 6115 6116 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6117 for (unsigned i = 0; i != NumFields; ++i) { 6118 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6119 6120 // Get the type for the field. 6121 Type *FDTy = FD->getType().getTypePtr(); 6122 6123 if (!FD->isAnonymousStructOrUnion()) { 6124 // Remember all fields written by the user. 6125 RecFields.push_back(FD); 6126 } 6127 6128 // If the field is already invalid for some reason, don't emit more 6129 // diagnostics about it. 6130 if (FD->isInvalidDecl()) { 6131 EnclosingDecl->setInvalidDecl(); 6132 continue; 6133 } 6134 6135 // C99 6.7.2.1p2: 6136 // A structure or union shall not contain a member with 6137 // incomplete or function type (hence, a structure shall not 6138 // contain an instance of itself, but may contain a pointer to 6139 // an instance of itself), except that the last member of a 6140 // structure with more than one named member may have incomplete 6141 // array type; such a structure (and any union containing, 6142 // possibly recursively, a member that is such a structure) 6143 // shall not be a member of a structure or an element of an 6144 // array. 6145 if (FDTy->isFunctionType()) { 6146 // Field declared as a function. 6147 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6148 << FD->getDeclName(); 6149 FD->setInvalidDecl(); 6150 EnclosingDecl->setInvalidDecl(); 6151 continue; 6152 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6153 Record && Record->isStruct()) { 6154 // Flexible array member. 6155 if (NumNamedMembers < 1) { 6156 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6157 << FD->getDeclName(); 6158 FD->setInvalidDecl(); 6159 EnclosingDecl->setInvalidDecl(); 6160 continue; 6161 } 6162 if (!FD->getType()->isDependentType() && 6163 !Context.getBaseElementType(FD->getType())->isPODType()) { 6164 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6165 << FD->getDeclName() << FD->getType(); 6166 FD->setInvalidDecl(); 6167 EnclosingDecl->setInvalidDecl(); 6168 continue; 6169 } 6170 6171 // Okay, we have a legal flexible array member at the end of the struct. 6172 if (Record) 6173 Record->setHasFlexibleArrayMember(true); 6174 } else if (!FDTy->isDependentType() && 6175 RequireCompleteType(FD->getLocation(), FD->getType(), 6176 diag::err_field_incomplete)) { 6177 // Incomplete type 6178 FD->setInvalidDecl(); 6179 EnclosingDecl->setInvalidDecl(); 6180 continue; 6181 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6182 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6183 // If this is a member of a union, then entire union becomes "flexible". 6184 if (Record && Record->isUnion()) { 6185 Record->setHasFlexibleArrayMember(true); 6186 } else { 6187 // If this is a struct/class and this is not the last element, reject 6188 // it. Note that GCC supports variable sized arrays in the middle of 6189 // structures. 6190 if (i != NumFields-1) 6191 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6192 << FD->getDeclName() << FD->getType(); 6193 else { 6194 // We support flexible arrays at the end of structs in 6195 // other structs as an extension. 6196 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6197 << FD->getDeclName(); 6198 if (Record) 6199 Record->setHasFlexibleArrayMember(true); 6200 } 6201 } 6202 } 6203 if (Record && FDTTy->getDecl()->hasObjectMember()) 6204 Record->setHasObjectMember(true); 6205 } else if (FDTy->isObjCObjectType()) { 6206 /// A field cannot be an Objective-c object 6207 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6208 FD->setInvalidDecl(); 6209 EnclosingDecl->setInvalidDecl(); 6210 continue; 6211 } else if (getLangOptions().ObjC1 && 6212 getLangOptions().getGCMode() != LangOptions::NonGC && 6213 Record && 6214 (FD->getType()->isObjCObjectPointerType() || 6215 FD->getType().isObjCGCStrong())) 6216 Record->setHasObjectMember(true); 6217 // Keep track of the number of named members. 6218 if (FD->getIdentifier()) 6219 ++NumNamedMembers; 6220 } 6221 6222 // Okay, we successfully defined 'Record'. 6223 if (Record) { 6224 Record->completeDefinition(); 6225 } else { 6226 ObjCIvarDecl **ClsFields = 6227 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6228 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6229 ID->setLocEnd(RBrac); 6230 // Add ivar's to class's DeclContext. 6231 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6232 ClsFields[i]->setLexicalDeclContext(ID); 6233 ID->addDecl(ClsFields[i]); 6234 } 6235 // Must enforce the rule that ivars in the base classes may not be 6236 // duplicates. 6237 if (ID->getSuperClass()) 6238 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6239 } else if (ObjCImplementationDecl *IMPDecl = 6240 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6241 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6242 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6243 // Ivar declared in @implementation never belongs to the implementation. 6244 // Only it is in implementation's lexical context. 6245 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6246 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6247 } else if (ObjCCategoryDecl *CDecl = 6248 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6249 // case of ivars in class extension; all other cases have been 6250 // reported as errors elsewhere. 6251 // FIXME. Class extension does not have a LocEnd field. 6252 // CDecl->setLocEnd(RBrac); 6253 // Add ivar's to class extension's DeclContext. 6254 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6255 ClsFields[i]->setLexicalDeclContext(CDecl); 6256 CDecl->addDecl(ClsFields[i]); 6257 } 6258 } 6259 } 6260 6261 if (Attr) 6262 ProcessDeclAttributeList(S, Record, Attr); 6263} 6264 6265/// \brief Determine whether the given integral value is representable within 6266/// the given type T. 6267static bool isRepresentableIntegerValue(ASTContext &Context, 6268 llvm::APSInt &Value, 6269 QualType T) { 6270 assert(T->isIntegralType() && "Integral type required!"); 6271 unsigned BitWidth = Context.getIntWidth(T); 6272 6273 if (Value.isUnsigned() || Value.isNonNegative()) 6274 return Value.getActiveBits() < BitWidth; 6275 6276 return Value.getMinSignedBits() <= BitWidth; 6277} 6278 6279// \brief Given an integral type, return the next larger integral type 6280// (or a NULL type of no such type exists). 6281static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6282 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6283 // enum checking below. 6284 assert(T->isIntegralType() && "Integral type required!"); 6285 const unsigned NumTypes = 4; 6286 QualType SignedIntegralTypes[NumTypes] = { 6287 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6288 }; 6289 QualType UnsignedIntegralTypes[NumTypes] = { 6290 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6291 Context.UnsignedLongLongTy 6292 }; 6293 6294 unsigned BitWidth = Context.getTypeSize(T); 6295 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6296 : UnsignedIntegralTypes; 6297 for (unsigned I = 0; I != NumTypes; ++I) 6298 if (Context.getTypeSize(Types[I]) > BitWidth) 6299 return Types[I]; 6300 6301 return QualType(); 6302} 6303 6304EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6305 EnumConstantDecl *LastEnumConst, 6306 SourceLocation IdLoc, 6307 IdentifierInfo *Id, 6308 ExprArg val) { 6309 Expr *Val = (Expr *)val.get(); 6310 6311 unsigned IntWidth = Context.Target.getIntWidth(); 6312 llvm::APSInt EnumVal(IntWidth); 6313 QualType EltTy; 6314 if (Val) { 6315 if (Enum->isDependentType() || Val->isTypeDependent()) 6316 EltTy = Context.DependentTy; 6317 else { 6318 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6319 SourceLocation ExpLoc; 6320 if (!Val->isValueDependent() && 6321 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6322 Val = 0; 6323 } else { 6324 if (!getLangOptions().CPlusPlus) { 6325 // C99 6.7.2.2p2: 6326 // The expression that defines the value of an enumeration constant 6327 // shall be an integer constant expression that has a value 6328 // representable as an int. 6329 6330 // Complain if the value is not representable in an int. 6331 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6332 Diag(IdLoc, diag::ext_enum_value_not_int) 6333 << EnumVal.toString(10) << Val->getSourceRange() 6334 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6335 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6336 // Force the type of the expression to 'int'. 6337 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6338 6339 if (Val != val.get()) { 6340 val.release(); 6341 val = Val; 6342 } 6343 } 6344 } 6345 6346 // C++0x [dcl.enum]p5: 6347 // If the underlying type is not fixed, the type of each enumerator 6348 // is the type of its initializing value: 6349 // - If an initializer is specified for an enumerator, the 6350 // initializing value has the same type as the expression. 6351 EltTy = Val->getType(); 6352 } 6353 } 6354 } 6355 6356 if (!Val) { 6357 if (Enum->isDependentType()) 6358 EltTy = Context.DependentTy; 6359 else if (!LastEnumConst) { 6360 // C++0x [dcl.enum]p5: 6361 // If the underlying type is not fixed, the type of each enumerator 6362 // is the type of its initializing value: 6363 // - If no initializer is specified for the first enumerator, the 6364 // initializing value has an unspecified integral type. 6365 // 6366 // GCC uses 'int' for its unspecified integral type, as does 6367 // C99 6.7.2.2p3. 6368 EltTy = Context.IntTy; 6369 } else { 6370 // Assign the last value + 1. 6371 EnumVal = LastEnumConst->getInitVal(); 6372 ++EnumVal; 6373 EltTy = LastEnumConst->getType(); 6374 6375 // Check for overflow on increment. 6376 if (EnumVal < LastEnumConst->getInitVal()) { 6377 // C++0x [dcl.enum]p5: 6378 // If the underlying type is not fixed, the type of each enumerator 6379 // is the type of its initializing value: 6380 // 6381 // - Otherwise the type of the initializing value is the same as 6382 // the type of the initializing value of the preceding enumerator 6383 // unless the incremented value is not representable in that type, 6384 // in which case the type is an unspecified integral type 6385 // sufficient to contain the incremented value. If no such type 6386 // exists, the program is ill-formed. 6387 QualType T = getNextLargerIntegralType(Context, EltTy); 6388 if (T.isNull()) { 6389 // There is no integral type larger enough to represent this 6390 // value. Complain, then allow the value to wrap around. 6391 EnumVal = LastEnumConst->getInitVal(); 6392 EnumVal.zext(EnumVal.getBitWidth() * 2); 6393 Diag(IdLoc, diag::warn_enumerator_too_large) 6394 << EnumVal.toString(10); 6395 } else { 6396 EltTy = T; 6397 } 6398 6399 // Retrieve the last enumerator's value, extent that type to the 6400 // type that is supposed to be large enough to represent the incremented 6401 // value, then increment. 6402 EnumVal = LastEnumConst->getInitVal(); 6403 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6404 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6405 ++EnumVal; 6406 6407 // If we're not in C++, diagnose the overflow of enumerator values, 6408 // which in C99 means that the enumerator value is not representable in 6409 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6410 // permits enumerator values that are representable in some larger 6411 // integral type. 6412 if (!getLangOptions().CPlusPlus && !T.isNull()) 6413 Diag(IdLoc, diag::warn_enum_value_overflow); 6414 } else if (!getLangOptions().CPlusPlus && 6415 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6416 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6417 Diag(IdLoc, diag::ext_enum_value_not_int) 6418 << EnumVal.toString(10) << 1; 6419 } 6420 } 6421 } 6422 6423 if (!EltTy->isDependentType()) { 6424 // Make the enumerator value match the signedness and size of the 6425 // enumerator's type. 6426 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6427 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6428 } 6429 6430 val.release(); 6431 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6432 Val, EnumVal); 6433} 6434 6435 6436Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6437 DeclPtrTy lastEnumConst, 6438 SourceLocation IdLoc, 6439 IdentifierInfo *Id, 6440 SourceLocation EqualLoc, ExprTy *val) { 6441 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6442 EnumConstantDecl *LastEnumConst = 6443 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6444 Expr *Val = static_cast<Expr*>(val); 6445 6446 // The scope passed in may not be a decl scope. Zip up the scope tree until 6447 // we find one that is. 6448 S = getNonFieldDeclScope(S); 6449 6450 // Verify that there isn't already something declared with this name in this 6451 // scope. 6452 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6453 ForRedeclaration); 6454 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6455 // Maybe we will complain about the shadowed template parameter. 6456 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6457 // Just pretend that we didn't see the previous declaration. 6458 PrevDecl = 0; 6459 } 6460 6461 if (PrevDecl) { 6462 // When in C++, we may get a TagDecl with the same name; in this case the 6463 // enum constant will 'hide' the tag. 6464 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6465 "Received TagDecl when not in C++!"); 6466 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6467 if (isa<EnumConstantDecl>(PrevDecl)) 6468 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6469 else 6470 Diag(IdLoc, diag::err_redefinition) << Id; 6471 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6472 if (Val) Val->Destroy(Context); 6473 return DeclPtrTy(); 6474 } 6475 } 6476 6477 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6478 IdLoc, Id, Owned(Val)); 6479 6480 // Register this decl in the current scope stack. 6481 if (New) { 6482 New->setAccess(TheEnumDecl->getAccess()); 6483 PushOnScopeChains(New, S); 6484 } 6485 6486 return DeclPtrTy::make(New); 6487} 6488 6489void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6490 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6491 DeclPtrTy *Elements, unsigned NumElements, 6492 Scope *S, AttributeList *Attr) { 6493 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6494 QualType EnumType = Context.getTypeDeclType(Enum); 6495 6496 if (Attr) 6497 ProcessDeclAttributeList(S, Enum, Attr); 6498 6499 if (Enum->isDependentType()) { 6500 for (unsigned i = 0; i != NumElements; ++i) { 6501 EnumConstantDecl *ECD = 6502 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6503 if (!ECD) continue; 6504 6505 ECD->setType(EnumType); 6506 } 6507 6508 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6509 return; 6510 } 6511 6512 // TODO: If the result value doesn't fit in an int, it must be a long or long 6513 // long value. ISO C does not support this, but GCC does as an extension, 6514 // emit a warning. 6515 unsigned IntWidth = Context.Target.getIntWidth(); 6516 unsigned CharWidth = Context.Target.getCharWidth(); 6517 unsigned ShortWidth = Context.Target.getShortWidth(); 6518 6519 // Verify that all the values are okay, compute the size of the values, and 6520 // reverse the list. 6521 unsigned NumNegativeBits = 0; 6522 unsigned NumPositiveBits = 0; 6523 6524 // Keep track of whether all elements have type int. 6525 bool AllElementsInt = true; 6526 6527 for (unsigned i = 0; i != NumElements; ++i) { 6528 EnumConstantDecl *ECD = 6529 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6530 if (!ECD) continue; // Already issued a diagnostic. 6531 6532 const llvm::APSInt &InitVal = ECD->getInitVal(); 6533 6534 // Keep track of the size of positive and negative values. 6535 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6536 NumPositiveBits = std::max(NumPositiveBits, 6537 (unsigned)InitVal.getActiveBits()); 6538 else 6539 NumNegativeBits = std::max(NumNegativeBits, 6540 (unsigned)InitVal.getMinSignedBits()); 6541 6542 // Keep track of whether every enum element has type int (very commmon). 6543 if (AllElementsInt) 6544 AllElementsInt = ECD->getType() == Context.IntTy; 6545 } 6546 6547 // Figure out the type that should be used for this enum. 6548 // FIXME: Support -fshort-enums. 6549 QualType BestType; 6550 unsigned BestWidth; 6551 6552 // C++0x N3000 [conv.prom]p3: 6553 // An rvalue of an unscoped enumeration type whose underlying 6554 // type is not fixed can be converted to an rvalue of the first 6555 // of the following types that can represent all the values of 6556 // the enumeration: int, unsigned int, long int, unsigned long 6557 // int, long long int, or unsigned long long int. 6558 // C99 6.4.4.3p2: 6559 // An identifier declared as an enumeration constant has type int. 6560 // The C99 rule is modified by a gcc extension 6561 QualType BestPromotionType; 6562 6563 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6564 6565 if (NumNegativeBits) { 6566 // If there is a negative value, figure out the smallest integer type (of 6567 // int/long/longlong) that fits. 6568 // If it's packed, check also if it fits a char or a short. 6569 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6570 BestType = Context.SignedCharTy; 6571 BestWidth = CharWidth; 6572 } else if (Packed && NumNegativeBits <= ShortWidth && 6573 NumPositiveBits < ShortWidth) { 6574 BestType = Context.ShortTy; 6575 BestWidth = ShortWidth; 6576 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6577 BestType = Context.IntTy; 6578 BestWidth = IntWidth; 6579 } else { 6580 BestWidth = Context.Target.getLongWidth(); 6581 6582 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6583 BestType = Context.LongTy; 6584 } else { 6585 BestWidth = Context.Target.getLongLongWidth(); 6586 6587 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6588 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6589 BestType = Context.LongLongTy; 6590 } 6591 } 6592 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6593 } else { 6594 // If there is no negative value, figure out the smallest type that fits 6595 // all of the enumerator values. 6596 // If it's packed, check also if it fits a char or a short. 6597 if (Packed && NumPositiveBits <= CharWidth) { 6598 BestType = Context.UnsignedCharTy; 6599 BestPromotionType = Context.IntTy; 6600 BestWidth = CharWidth; 6601 } else if (Packed && NumPositiveBits <= ShortWidth) { 6602 BestType = Context.UnsignedShortTy; 6603 BestPromotionType = Context.IntTy; 6604 BestWidth = ShortWidth; 6605 } else if (NumPositiveBits <= IntWidth) { 6606 BestType = Context.UnsignedIntTy; 6607 BestWidth = IntWidth; 6608 BestPromotionType 6609 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6610 ? Context.UnsignedIntTy : Context.IntTy; 6611 } else if (NumPositiveBits <= 6612 (BestWidth = Context.Target.getLongWidth())) { 6613 BestType = Context.UnsignedLongTy; 6614 BestPromotionType 6615 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6616 ? Context.UnsignedLongTy : Context.LongTy; 6617 } else { 6618 BestWidth = Context.Target.getLongLongWidth(); 6619 assert(NumPositiveBits <= BestWidth && 6620 "How could an initializer get larger than ULL?"); 6621 BestType = Context.UnsignedLongLongTy; 6622 BestPromotionType 6623 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6624 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6625 } 6626 } 6627 6628 // Loop over all of the enumerator constants, changing their types to match 6629 // the type of the enum if needed. 6630 for (unsigned i = 0; i != NumElements; ++i) { 6631 EnumConstantDecl *ECD = 6632 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6633 if (!ECD) continue; // Already issued a diagnostic. 6634 6635 // Standard C says the enumerators have int type, but we allow, as an 6636 // extension, the enumerators to be larger than int size. If each 6637 // enumerator value fits in an int, type it as an int, otherwise type it the 6638 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6639 // that X has type 'int', not 'unsigned'. 6640 6641 // Determine whether the value fits into an int. 6642 llvm::APSInt InitVal = ECD->getInitVal(); 6643 6644 // If it fits into an integer type, force it. Otherwise force it to match 6645 // the enum decl type. 6646 QualType NewTy; 6647 unsigned NewWidth; 6648 bool NewSign; 6649 if (!getLangOptions().CPlusPlus && 6650 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6651 NewTy = Context.IntTy; 6652 NewWidth = IntWidth; 6653 NewSign = true; 6654 } else if (ECD->getType() == BestType) { 6655 // Already the right type! 6656 if (getLangOptions().CPlusPlus) 6657 // C++ [dcl.enum]p4: Following the closing brace of an 6658 // enum-specifier, each enumerator has the type of its 6659 // enumeration. 6660 ECD->setType(EnumType); 6661 continue; 6662 } else { 6663 NewTy = BestType; 6664 NewWidth = BestWidth; 6665 NewSign = BestType->isSignedIntegerType(); 6666 } 6667 6668 // Adjust the APSInt value. 6669 InitVal.extOrTrunc(NewWidth); 6670 InitVal.setIsSigned(NewSign); 6671 ECD->setInitVal(InitVal); 6672 6673 // Adjust the Expr initializer and type. 6674 if (ECD->getInitExpr()) 6675 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6676 CastExpr::CK_IntegralCast, 6677 ECD->getInitExpr(), 6678 CXXBaseSpecifierArray(), 6679 /*isLvalue=*/false)); 6680 if (getLangOptions().CPlusPlus) 6681 // C++ [dcl.enum]p4: Following the closing brace of an 6682 // enum-specifier, each enumerator has the type of its 6683 // enumeration. 6684 ECD->setType(EnumType); 6685 else 6686 ECD->setType(NewTy); 6687 } 6688 6689 Enum->completeDefinition(BestType, BestPromotionType, 6690 NumPositiveBits, NumNegativeBits); 6691} 6692 6693Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6694 ExprArg expr) { 6695 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6696 6697 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6698 Loc, AsmString); 6699 CurContext->addDecl(New); 6700 return DeclPtrTy::make(New); 6701} 6702 6703void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6704 SourceLocation PragmaLoc, 6705 SourceLocation NameLoc) { 6706 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6707 6708 if (PrevDecl) { 6709 PrevDecl->addAttr(::new (Context) WeakAttr()); 6710 } else { 6711 (void)WeakUndeclaredIdentifiers.insert( 6712 std::pair<IdentifierInfo*,WeakInfo> 6713 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6714 } 6715} 6716 6717void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6718 IdentifierInfo* AliasName, 6719 SourceLocation PragmaLoc, 6720 SourceLocation NameLoc, 6721 SourceLocation AliasNameLoc) { 6722 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6723 LookupOrdinaryName); 6724 WeakInfo W = WeakInfo(Name, NameLoc); 6725 6726 if (PrevDecl) { 6727 if (!PrevDecl->hasAttr<AliasAttr>()) 6728 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6729 DeclApplyPragmaWeak(TUScope, ND, W); 6730 } else { 6731 (void)WeakUndeclaredIdentifiers.insert( 6732 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6733 } 6734} 6735