SemaDecl.cpp revision 0ed2e0823cc7b727abd9307db4cd887f293eebe2
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 "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "clang/AST/APValue.h" 21#include "clang/AST/ASTConsumer.h" 22#include "clang/AST/ASTContext.h" 23#include "clang/AST/CXXInheritance.h" 24#include "clang/AST/DeclCXX.h" 25#include "clang/AST/DeclObjC.h" 26#include "clang/AST/DeclTemplate.h" 27#include "clang/AST/ExprCXX.h" 28#include "clang/AST/StmtCXX.h" 29#include "clang/Sema/DeclSpec.h" 30#include "clang/Sema/ParsedTemplate.h" 31#include "clang/Parse/ParseDiagnostic.h" 32#include "clang/Basic/PartialDiagnostic.h" 33#include "clang/Basic/SourceManager.h" 34#include "clang/Basic/TargetInfo.h" 35// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 36#include "clang/Lex/Preprocessor.h" 37#include "clang/Lex/HeaderSearch.h" 38#include "llvm/ADT/Triple.h" 39#include <algorithm> 40#include <cstring> 41#include <functional> 42using namespace clang; 43using namespace sema; 44 45Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 46 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 47} 48 49/// \brief If the identifier refers to a type name within this scope, 50/// return the declaration of that type. 51/// 52/// This routine performs ordinary name lookup of the identifier II 53/// within the given scope, with optional C++ scope specifier SS, to 54/// determine whether the name refers to a type. If so, returns an 55/// opaque pointer (actually a QualType) corresponding to that 56/// type. Otherwise, returns NULL. 57/// 58/// If name lookup results in an ambiguity, this routine will complain 59/// and then return NULL. 60ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 61 Scope *S, CXXScopeSpec *SS, 62 bool isClassName, 63 ParsedType ObjectTypePtr) { 64 // Determine where we will perform name lookup. 65 DeclContext *LookupCtx = 0; 66 if (ObjectTypePtr) { 67 QualType ObjectType = ObjectTypePtr.get(); 68 if (ObjectType->isRecordType()) 69 LookupCtx = computeDeclContext(ObjectType); 70 } else if (SS && SS->isNotEmpty()) { 71 LookupCtx = computeDeclContext(*SS, false); 72 73 if (!LookupCtx) { 74 if (isDependentScopeSpecifier(*SS)) { 75 // C++ [temp.res]p3: 76 // A qualified-id that refers to a type and in which the 77 // nested-name-specifier depends on a template-parameter (14.6.2) 78 // shall be prefixed by the keyword typename to indicate that the 79 // qualified-id denotes a type, forming an 80 // elaborated-type-specifier (7.1.5.3). 81 // 82 // We therefore do not perform any name lookup if the result would 83 // refer to a member of an unknown specialization. 84 if (!isClassName) 85 return ParsedType(); 86 87 // We know from the grammar that this name refers to a type, 88 // so build a dependent node to describe the type. 89 QualType T = 90 CheckTypenameType(ETK_None, SS->getScopeRep(), II, 91 SourceLocation(), SS->getRange(), NameLoc); 92 return ParsedType::make(T); 93 } 94 95 return ParsedType(); 96 } 97 98 if (!LookupCtx->isDependentContext() && 99 RequireCompleteDeclContext(*SS, LookupCtx)) 100 return ParsedType(); 101 } 102 103 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 104 // lookup for class-names. 105 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 106 LookupOrdinaryName; 107 LookupResult Result(*this, &II, NameLoc, Kind); 108 if (LookupCtx) { 109 // Perform "qualified" name lookup into the declaration context we 110 // computed, which is either the type of the base of a member access 111 // expression or the declaration context associated with a prior 112 // nested-name-specifier. 113 LookupQualifiedName(Result, LookupCtx); 114 115 if (ObjectTypePtr && Result.empty()) { 116 // C++ [basic.lookup.classref]p3: 117 // If the unqualified-id is ~type-name, the type-name is looked up 118 // in the context of the entire postfix-expression. If the type T of 119 // the object expression is of a class type C, the type-name is also 120 // looked up in the scope of class C. At least one of the lookups shall 121 // find a name that refers to (possibly cv-qualified) T. 122 LookupName(Result, S); 123 } 124 } else { 125 // Perform unqualified name lookup. 126 LookupName(Result, S); 127 } 128 129 NamedDecl *IIDecl = 0; 130 switch (Result.getResultKind()) { 131 case LookupResult::NotFound: 132 case LookupResult::NotFoundInCurrentInstantiation: 133 case LookupResult::FoundOverloaded: 134 case LookupResult::FoundUnresolvedValue: 135 Result.suppressDiagnostics(); 136 return ParsedType(); 137 138 case LookupResult::Ambiguous: 139 // Recover from type-hiding ambiguities by hiding the type. We'll 140 // do the lookup again when looking for an object, and we can 141 // diagnose the error then. If we don't do this, then the error 142 // about hiding the type will be immediately followed by an error 143 // that only makes sense if the identifier was treated like a type. 144 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 145 Result.suppressDiagnostics(); 146 return ParsedType(); 147 } 148 149 // Look to see if we have a type anywhere in the list of results. 150 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 151 Res != ResEnd; ++Res) { 152 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 153 if (!IIDecl || 154 (*Res)->getLocation().getRawEncoding() < 155 IIDecl->getLocation().getRawEncoding()) 156 IIDecl = *Res; 157 } 158 } 159 160 if (!IIDecl) { 161 // None of the entities we found is a type, so there is no way 162 // to even assume that the result is a type. In this case, don't 163 // complain about the ambiguity. The parser will either try to 164 // perform this lookup again (e.g., as an object name), which 165 // will produce the ambiguity, or will complain that it expected 166 // a type name. 167 Result.suppressDiagnostics(); 168 return ParsedType(); 169 } 170 171 // We found a type within the ambiguous lookup; diagnose the 172 // ambiguity and then return that type. This might be the right 173 // answer, or it might not be, but it suppresses any attempt to 174 // perform the name lookup again. 175 break; 176 177 case LookupResult::Found: 178 IIDecl = Result.getFoundDecl(); 179 break; 180 } 181 182 assert(IIDecl && "Didn't find decl"); 183 184 QualType T; 185 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 186 DiagnoseUseOfDecl(IIDecl, NameLoc); 187 188 if (T.isNull()) 189 T = Context.getTypeDeclType(TD); 190 191 if (SS) 192 T = getElaboratedType(ETK_None, *SS, T); 193 194 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 195 T = Context.getObjCInterfaceType(IDecl); 196 } else { 197 // If it's not plausibly a type, suppress diagnostics. 198 Result.suppressDiagnostics(); 199 return ParsedType(); 200 } 201 202 return ParsedType::make(T); 203} 204 205/// isTagName() - This method is called *for error recovery purposes only* 206/// to determine if the specified name is a valid tag name ("struct foo"). If 207/// so, this returns the TST for the tag corresponding to it (TST_enum, 208/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 209/// where the user forgot to specify the tag. 210DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 211 // Do a tag name lookup in this scope. 212 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 213 LookupName(R, S, false); 214 R.suppressDiagnostics(); 215 if (R.getResultKind() == LookupResult::Found) 216 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 217 switch (TD->getTagKind()) { 218 default: return DeclSpec::TST_unspecified; 219 case TTK_Struct: return DeclSpec::TST_struct; 220 case TTK_Union: return DeclSpec::TST_union; 221 case TTK_Class: return DeclSpec::TST_class; 222 case TTK_Enum: return DeclSpec::TST_enum; 223 } 224 } 225 226 return DeclSpec::TST_unspecified; 227} 228 229bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 230 SourceLocation IILoc, 231 Scope *S, 232 CXXScopeSpec *SS, 233 ParsedType &SuggestedType) { 234 // We don't have anything to suggest (yet). 235 SuggestedType = ParsedType(); 236 237 // There may have been a typo in the name of the type. Look up typo 238 // results, in case we have something that we can suggest. 239 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 240 NotForRedeclaration); 241 242 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 243 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 244 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 245 !Result->isInvalidDecl()) { 246 // We found a similarly-named type or interface; suggest that. 247 if (!SS || !SS->isSet()) 248 Diag(IILoc, diag::err_unknown_typename_suggest) 249 << &II << Lookup.getLookupName() 250 << FixItHint::CreateReplacement(SourceRange(IILoc), 251 Result->getNameAsString()); 252 else if (DeclContext *DC = computeDeclContext(*SS, false)) 253 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 254 << &II << DC << Lookup.getLookupName() << SS->getRange() 255 << FixItHint::CreateReplacement(SourceRange(IILoc), 256 Result->getNameAsString()); 257 else 258 llvm_unreachable("could not have corrected a typo here"); 259 260 Diag(Result->getLocation(), diag::note_previous_decl) 261 << Result->getDeclName(); 262 263 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 264 return true; 265 } 266 } else if (Lookup.empty()) { 267 // We corrected to a keyword. 268 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 269 Diag(IILoc, diag::err_unknown_typename_suggest) 270 << &II << Corrected; 271 return true; 272 } 273 } 274 275 if (getLangOptions().CPlusPlus) { 276 // See if II is a class template that the user forgot to pass arguments to. 277 UnqualifiedId Name; 278 Name.setIdentifier(&II, IILoc); 279 CXXScopeSpec EmptySS; 280 TemplateTy TemplateResult; 281 bool MemberOfUnknownSpecialization; 282 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 283 Name, ParsedType(), true, TemplateResult, 284 MemberOfUnknownSpecialization) == TNK_Type_template) { 285 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 286 Diag(IILoc, diag::err_template_missing_args) << TplName; 287 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 288 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 289 << TplDecl->getTemplateParameters()->getSourceRange(); 290 } 291 return true; 292 } 293 } 294 295 // FIXME: Should we move the logic that tries to recover from a missing tag 296 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 297 298 if (!SS || (!SS->isSet() && !SS->isInvalid())) 299 Diag(IILoc, diag::err_unknown_typename) << &II; 300 else if (DeclContext *DC = computeDeclContext(*SS, false)) 301 Diag(IILoc, diag::err_typename_nested_not_found) 302 << &II << DC << SS->getRange(); 303 else if (isDependentScopeSpecifier(*SS)) { 304 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 305 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 306 << SourceRange(SS->getRange().getBegin(), IILoc) 307 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 308 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 309 } else { 310 assert(SS && SS->isInvalid() && 311 "Invalid scope specifier has already been diagnosed"); 312 } 313 314 return true; 315} 316 317// Determines the context to return to after temporarily entering a 318// context. This depends in an unnecessarily complicated way on the 319// exact ordering of callbacks from the parser. 320DeclContext *Sema::getContainingDC(DeclContext *DC) { 321 322 // Functions defined inline within classes aren't parsed until we've 323 // finished parsing the top-level class, so the top-level class is 324 // the context we'll need to return to. 325 if (isa<FunctionDecl>(DC)) { 326 DC = DC->getLexicalParent(); 327 328 // A function not defined within a class will always return to its 329 // lexical context. 330 if (!isa<CXXRecordDecl>(DC)) 331 return DC; 332 333 // A C++ inline method/friend is parsed *after* the topmost class 334 // it was declared in is fully parsed ("complete"); the topmost 335 // class is the context we need to return to. 336 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 337 DC = RD; 338 339 // Return the declaration context of the topmost class the inline method is 340 // declared in. 341 return DC; 342 } 343 344 // ObjCMethodDecls are parsed (for some reason) outside the context 345 // of the class. 346 if (isa<ObjCMethodDecl>(DC)) 347 return DC->getLexicalParent()->getLexicalParent(); 348 349 return DC->getLexicalParent(); 350} 351 352void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 353 assert(getContainingDC(DC) == CurContext && 354 "The next DeclContext should be lexically contained in the current one."); 355 CurContext = DC; 356 S->setEntity(DC); 357} 358 359void Sema::PopDeclContext() { 360 assert(CurContext && "DeclContext imbalance!"); 361 362 CurContext = getContainingDC(CurContext); 363 assert(CurContext && "Popped translation unit!"); 364} 365 366/// EnterDeclaratorContext - Used when we must lookup names in the context 367/// of a declarator's nested name specifier. 368/// 369void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 370 // C++0x [basic.lookup.unqual]p13: 371 // A name used in the definition of a static data member of class 372 // X (after the qualified-id of the static member) is looked up as 373 // if the name was used in a member function of X. 374 // C++0x [basic.lookup.unqual]p14: 375 // If a variable member of a namespace is defined outside of the 376 // scope of its namespace then any name used in the definition of 377 // the variable member (after the declarator-id) is looked up as 378 // if the definition of the variable member occurred in its 379 // namespace. 380 // Both of these imply that we should push a scope whose context 381 // is the semantic context of the declaration. We can't use 382 // PushDeclContext here because that context is not necessarily 383 // lexically contained in the current context. Fortunately, 384 // the containing scope should have the appropriate information. 385 386 assert(!S->getEntity() && "scope already has entity"); 387 388#ifndef NDEBUG 389 Scope *Ancestor = S->getParent(); 390 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 391 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 392#endif 393 394 CurContext = DC; 395 S->setEntity(DC); 396} 397 398void Sema::ExitDeclaratorContext(Scope *S) { 399 assert(S->getEntity() == CurContext && "Context imbalance!"); 400 401 // Switch back to the lexical context. The safety of this is 402 // enforced by an assert in EnterDeclaratorContext. 403 Scope *Ancestor = S->getParent(); 404 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 405 CurContext = (DeclContext*) Ancestor->getEntity(); 406 407 // We don't need to do anything with the scope, which is going to 408 // disappear. 409} 410 411/// \brief Determine whether we allow overloading of the function 412/// PrevDecl with another declaration. 413/// 414/// This routine determines whether overloading is possible, not 415/// whether some new function is actually an overload. It will return 416/// true in C++ (where we can always provide overloads) or, as an 417/// extension, in C when the previous function is already an 418/// overloaded function declaration or has the "overloadable" 419/// attribute. 420static bool AllowOverloadingOfFunction(LookupResult &Previous, 421 ASTContext &Context) { 422 if (Context.getLangOptions().CPlusPlus) 423 return true; 424 425 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 426 return true; 427 428 return (Previous.getResultKind() == LookupResult::Found 429 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 430} 431 432/// Add this decl to the scope shadowed decl chains. 433void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 434 // Move up the scope chain until we find the nearest enclosing 435 // non-transparent context. The declaration will be introduced into this 436 // scope. 437 while (S->getEntity() && 438 ((DeclContext *)S->getEntity())->isTransparentContext()) 439 S = S->getParent(); 440 441 // Add scoped declarations into their context, so that they can be 442 // found later. Declarations without a context won't be inserted 443 // into any context. 444 if (AddToContext) 445 CurContext->addDecl(D); 446 447 // Out-of-line definitions shouldn't be pushed into scope in C++. 448 // Out-of-line variable and function definitions shouldn't even in C. 449 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 450 D->isOutOfLine()) 451 return; 452 453 // Template instantiations should also not be pushed into scope. 454 if (isa<FunctionDecl>(D) && 455 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 456 return; 457 458 // If this replaces anything in the current scope, 459 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 460 IEnd = IdResolver.end(); 461 for (; I != IEnd; ++I) { 462 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 463 S->RemoveDecl(*I); 464 IdResolver.RemoveDecl(*I); 465 466 // Should only need to replace one decl. 467 break; 468 } 469 } 470 471 S->AddDecl(D); 472 IdResolver.AddDecl(D); 473} 474 475bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 476 return IdResolver.isDeclInScope(D, Ctx, Context, S); 477} 478 479Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 480 DeclContext *TargetDC = DC->getPrimaryContext(); 481 do { 482 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 483 if (ScopeDC->getPrimaryContext() == TargetDC) 484 return S; 485 } while ((S = S->getParent())); 486 487 return 0; 488} 489 490static bool isOutOfScopePreviousDeclaration(NamedDecl *, 491 DeclContext*, 492 ASTContext&); 493 494/// Filters out lookup results that don't fall within the given scope 495/// as determined by isDeclInScope. 496static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 497 DeclContext *Ctx, Scope *S, 498 bool ConsiderLinkage) { 499 LookupResult::Filter F = R.makeFilter(); 500 while (F.hasNext()) { 501 NamedDecl *D = F.next(); 502 503 if (SemaRef.isDeclInScope(D, Ctx, S)) 504 continue; 505 506 if (ConsiderLinkage && 507 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 508 continue; 509 510 F.erase(); 511 } 512 513 F.done(); 514} 515 516static bool isUsingDecl(NamedDecl *D) { 517 return isa<UsingShadowDecl>(D) || 518 isa<UnresolvedUsingTypenameDecl>(D) || 519 isa<UnresolvedUsingValueDecl>(D); 520} 521 522/// Removes using shadow declarations from the lookup results. 523static void RemoveUsingDecls(LookupResult &R) { 524 LookupResult::Filter F = R.makeFilter(); 525 while (F.hasNext()) 526 if (isUsingDecl(F.next())) 527 F.erase(); 528 529 F.done(); 530} 531 532/// \brief Check for this common pattern: 533/// @code 534/// class S { 535/// S(const S&); // DO NOT IMPLEMENT 536/// void operator=(const S&); // DO NOT IMPLEMENT 537/// }; 538/// @endcode 539static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 540 // FIXME: Should check for private access too but access is set after we get 541 // the decl here. 542 if (D->isThisDeclarationADefinition()) 543 return false; 544 545 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 546 return CD->isCopyConstructor(); 547 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 548 return Method->isCopyAssignmentOperator(); 549 return false; 550} 551 552bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 553 assert(D); 554 555 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 556 return false; 557 558 // Ignore class templates. 559 if (D->getDeclContext()->isDependentContext()) 560 return false; 561 562 // We warn for unused decls internal to the translation unit. 563 if (D->getLinkage() == ExternalLinkage) 564 return false; 565 566 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 567 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 568 return false; 569 570 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 571 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 572 return false; 573 } else { 574 // 'static inline' functions are used in headers; don't warn. 575 if (FD->getStorageClass() == SC_Static && 576 FD->isInlineSpecified()) 577 return false; 578 } 579 580 if (FD->isThisDeclarationADefinition()) 581 return !Context.DeclMustBeEmitted(FD); 582 return true; 583 } 584 585 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 586 if (VD->isStaticDataMember() && 587 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 588 return false; 589 590 if ( VD->isFileVarDecl() && 591 !VD->getType().isConstant(Context)) 592 return !Context.DeclMustBeEmitted(VD); 593 } 594 595 return false; 596 } 597 598 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 599 if (!D) 600 return; 601 602 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 603 const FunctionDecl *First = FD->getFirstDeclaration(); 604 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 605 return; // First should already be in the vector. 606 } 607 608 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 609 const VarDecl *First = VD->getFirstDeclaration(); 610 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 611 return; // First should already be in the vector. 612 } 613 614 if (ShouldWarnIfUnusedFileScopedDecl(D)) 615 UnusedFileScopedDecls.push_back(D); 616 } 617 618static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 619 if (D->isInvalidDecl()) 620 return false; 621 622 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 623 return false; 624 625 // White-list anything that isn't a local variable. 626 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 627 !D->getDeclContext()->isFunctionOrMethod()) 628 return false; 629 630 // Types of valid local variables should be complete, so this should succeed. 631 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 632 633 // White-list anything with an __attribute__((unused)) type. 634 QualType Ty = VD->getType(); 635 636 // Only look at the outermost level of typedef. 637 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 638 if (TT->getDecl()->hasAttr<UnusedAttr>()) 639 return false; 640 } 641 642 // If we failed to complete the type for some reason, or if the type is 643 // dependent, don't diagnose the variable. 644 if (Ty->isIncompleteType() || Ty->isDependentType()) 645 return false; 646 647 if (const TagType *TT = Ty->getAs<TagType>()) { 648 const TagDecl *Tag = TT->getDecl(); 649 if (Tag->hasAttr<UnusedAttr>()) 650 return false; 651 652 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 653 // FIXME: Checking for the presence of a user-declared constructor 654 // isn't completely accurate; we'd prefer to check that the initializer 655 // has no side effects. 656 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 657 return false; 658 } 659 } 660 661 // TODO: __attribute__((unused)) templates? 662 } 663 664 return true; 665} 666 667void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 668 if (!ShouldDiagnoseUnusedDecl(D)) 669 return; 670 671 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 672 Diag(D->getLocation(), diag::warn_unused_exception_param) 673 << D->getDeclName(); 674 else 675 Diag(D->getLocation(), diag::warn_unused_variable) 676 << D->getDeclName(); 677} 678 679void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 680 if (S->decl_empty()) return; 681 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 682 "Scope shouldn't contain decls!"); 683 684 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 685 I != E; ++I) { 686 Decl *TmpD = (*I); 687 assert(TmpD && "This decl didn't get pushed??"); 688 689 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 690 NamedDecl *D = cast<NamedDecl>(TmpD); 691 692 if (!D->getDeclName()) continue; 693 694 // Diagnose unused variables in this scope. 695 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 696 DiagnoseUnusedDecl(D); 697 698 // Remove this name from our lexical scope. 699 IdResolver.RemoveDecl(D); 700 } 701} 702 703/// \brief Look for an Objective-C class in the translation unit. 704/// 705/// \param Id The name of the Objective-C class we're looking for. If 706/// typo-correction fixes this name, the Id will be updated 707/// to the fixed name. 708/// 709/// \param IdLoc The location of the name in the translation unit. 710/// 711/// \param TypoCorrection If true, this routine will attempt typo correction 712/// if there is no class with the given name. 713/// 714/// \returns The declaration of the named Objective-C class, or NULL if the 715/// class could not be found. 716ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 717 SourceLocation IdLoc, 718 bool TypoCorrection) { 719 // The third "scope" argument is 0 since we aren't enabling lazy built-in 720 // creation from this context. 721 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 722 723 if (!IDecl && TypoCorrection) { 724 // Perform typo correction at the given location, but only if we 725 // find an Objective-C class name. 726 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 727 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 728 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 729 Diag(IdLoc, diag::err_undef_interface_suggest) 730 << Id << IDecl->getDeclName() 731 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 732 Diag(IDecl->getLocation(), diag::note_previous_decl) 733 << IDecl->getDeclName(); 734 735 Id = IDecl->getIdentifier(); 736 } 737 } 738 739 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 740} 741 742/// getNonFieldDeclScope - Retrieves the innermost scope, starting 743/// from S, where a non-field would be declared. This routine copes 744/// with the difference between C and C++ scoping rules in structs and 745/// unions. For example, the following code is well-formed in C but 746/// ill-formed in C++: 747/// @code 748/// struct S6 { 749/// enum { BAR } e; 750/// }; 751/// 752/// void test_S6() { 753/// struct S6 a; 754/// a.e = BAR; 755/// } 756/// @endcode 757/// For the declaration of BAR, this routine will return a different 758/// scope. The scope S will be the scope of the unnamed enumeration 759/// within S6. In C++, this routine will return the scope associated 760/// with S6, because the enumeration's scope is a transparent 761/// context but structures can contain non-field names. In C, this 762/// routine will return the translation unit scope, since the 763/// enumeration's scope is a transparent context and structures cannot 764/// contain non-field names. 765Scope *Sema::getNonFieldDeclScope(Scope *S) { 766 while (((S->getFlags() & Scope::DeclScope) == 0) || 767 (S->getEntity() && 768 ((DeclContext *)S->getEntity())->isTransparentContext()) || 769 (S->isClassScope() && !getLangOptions().CPlusPlus)) 770 S = S->getParent(); 771 return S; 772} 773 774void Sema::InitBuiltinVaListType() { 775 if (!Context.getBuiltinVaListType().isNull()) 776 return; 777 778 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 779 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 780 LookupOrdinaryName, ForRedeclaration); 781 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 782 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 783} 784 785/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 786/// file scope. lazily create a decl for it. ForRedeclaration is true 787/// if we're creating this built-in in anticipation of redeclaring the 788/// built-in. 789NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 790 Scope *S, bool ForRedeclaration, 791 SourceLocation Loc) { 792 Builtin::ID BID = (Builtin::ID)bid; 793 794 if (Context.BuiltinInfo.hasVAListUse(BID)) 795 InitBuiltinVaListType(); 796 797 ASTContext::GetBuiltinTypeError Error; 798 QualType R = Context.GetBuiltinType(BID, Error); 799 switch (Error) { 800 case ASTContext::GE_None: 801 // Okay 802 break; 803 804 case ASTContext::GE_Missing_stdio: 805 if (ForRedeclaration) 806 Diag(Loc, diag::err_implicit_decl_requires_stdio) 807 << Context.BuiltinInfo.GetName(BID); 808 return 0; 809 810 case ASTContext::GE_Missing_setjmp: 811 if (ForRedeclaration) 812 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 813 << Context.BuiltinInfo.GetName(BID); 814 return 0; 815 } 816 817 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 818 Diag(Loc, diag::ext_implicit_lib_function_decl) 819 << Context.BuiltinInfo.GetName(BID) 820 << R; 821 if (Context.BuiltinInfo.getHeaderName(BID) && 822 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 823 != Diagnostic::Ignored) 824 Diag(Loc, diag::note_please_include_header) 825 << Context.BuiltinInfo.getHeaderName(BID) 826 << Context.BuiltinInfo.GetName(BID); 827 } 828 829 FunctionDecl *New = FunctionDecl::Create(Context, 830 Context.getTranslationUnitDecl(), 831 Loc, II, R, /*TInfo=*/0, 832 SC_Extern, 833 SC_None, false, 834 /*hasPrototype=*/true); 835 New->setImplicit(); 836 837 // Create Decl objects for each parameter, adding them to the 838 // FunctionDecl. 839 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 840 llvm::SmallVector<ParmVarDecl*, 16> Params; 841 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 842 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 843 FT->getArgType(i), /*TInfo=*/0, 844 SC_None, SC_None, 0)); 845 New->setParams(Params.data(), Params.size()); 846 } 847 848 AddKnownFunctionAttributes(New); 849 850 // TUScope is the translation-unit scope to insert this function into. 851 // FIXME: This is hideous. We need to teach PushOnScopeChains to 852 // relate Scopes to DeclContexts, and probably eliminate CurContext 853 // entirely, but we're not there yet. 854 DeclContext *SavedContext = CurContext; 855 CurContext = Context.getTranslationUnitDecl(); 856 PushOnScopeChains(New, TUScope); 857 CurContext = SavedContext; 858 return New; 859} 860 861/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 862/// same name and scope as a previous declaration 'Old'. Figure out 863/// how to resolve this situation, merging decls or emitting 864/// diagnostics as appropriate. If there was an error, set New to be invalid. 865/// 866void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 867 // If the new decl is known invalid already, don't bother doing any 868 // merging checks. 869 if (New->isInvalidDecl()) return; 870 871 // Allow multiple definitions for ObjC built-in typedefs. 872 // FIXME: Verify the underlying types are equivalent! 873 if (getLangOptions().ObjC1) { 874 const IdentifierInfo *TypeID = New->getIdentifier(); 875 switch (TypeID->getLength()) { 876 default: break; 877 case 2: 878 if (!TypeID->isStr("id")) 879 break; 880 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 881 // Install the built-in type for 'id', ignoring the current definition. 882 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 883 return; 884 case 5: 885 if (!TypeID->isStr("Class")) 886 break; 887 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 888 // Install the built-in type for 'Class', ignoring the current definition. 889 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 890 return; 891 case 3: 892 if (!TypeID->isStr("SEL")) 893 break; 894 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 895 // Install the built-in type for 'SEL', ignoring the current definition. 896 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 897 return; 898 case 8: 899 if (!TypeID->isStr("Protocol")) 900 break; 901 Context.setObjCProtoType(New->getUnderlyingType()); 902 return; 903 } 904 // Fall through - the typedef name was not a builtin type. 905 } 906 907 // Verify the old decl was also a type. 908 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 909 if (!Old) { 910 Diag(New->getLocation(), diag::err_redefinition_different_kind) 911 << New->getDeclName(); 912 913 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 914 if (OldD->getLocation().isValid()) 915 Diag(OldD->getLocation(), diag::note_previous_definition); 916 917 return New->setInvalidDecl(); 918 } 919 920 // If the old declaration is invalid, just give up here. 921 if (Old->isInvalidDecl()) 922 return New->setInvalidDecl(); 923 924 // Determine the "old" type we'll use for checking and diagnostics. 925 QualType OldType; 926 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 927 OldType = OldTypedef->getUnderlyingType(); 928 else 929 OldType = Context.getTypeDeclType(Old); 930 931 // If the typedef types are not identical, reject them in all languages and 932 // with any extensions enabled. 933 934 if (OldType != New->getUnderlyingType() && 935 Context.getCanonicalType(OldType) != 936 Context.getCanonicalType(New->getUnderlyingType())) { 937 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 938 << New->getUnderlyingType() << OldType; 939 if (Old->getLocation().isValid()) 940 Diag(Old->getLocation(), diag::note_previous_definition); 941 return New->setInvalidDecl(); 942 } 943 944 // The types match. Link up the redeclaration chain if the old 945 // declaration was a typedef. 946 // FIXME: this is a potential source of wierdness if the type 947 // spellings don't match exactly. 948 if (isa<TypedefDecl>(Old)) 949 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 950 951 if (getLangOptions().Microsoft) 952 return; 953 954 if (getLangOptions().CPlusPlus) { 955 // C++ [dcl.typedef]p2: 956 // In a given non-class scope, a typedef specifier can be used to 957 // redefine the name of any type declared in that scope to refer 958 // to the type to which it already refers. 959 if (!isa<CXXRecordDecl>(CurContext)) 960 return; 961 962 // C++0x [dcl.typedef]p4: 963 // In a given class scope, a typedef specifier can be used to redefine 964 // any class-name declared in that scope that is not also a typedef-name 965 // to refer to the type to which it already refers. 966 // 967 // This wording came in via DR424, which was a correction to the 968 // wording in DR56, which accidentally banned code like: 969 // 970 // struct S { 971 // typedef struct A { } A; 972 // }; 973 // 974 // in the C++03 standard. We implement the C++0x semantics, which 975 // allow the above but disallow 976 // 977 // struct S { 978 // typedef int I; 979 // typedef int I; 980 // }; 981 // 982 // since that was the intent of DR56. 983 if (!isa<TypedefDecl >(Old)) 984 return; 985 986 Diag(New->getLocation(), diag::err_redefinition) 987 << New->getDeclName(); 988 Diag(Old->getLocation(), diag::note_previous_definition); 989 return New->setInvalidDecl(); 990 } 991 992 // If we have a redefinition of a typedef in C, emit a warning. This warning 993 // is normally mapped to an error, but can be controlled with 994 // -Wtypedef-redefinition. If either the original or the redefinition is 995 // in a system header, don't emit this for compatibility with GCC. 996 if (getDiagnostics().getSuppressSystemWarnings() && 997 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 998 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 999 return; 1000 1001 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1002 << New->getDeclName(); 1003 Diag(Old->getLocation(), diag::note_previous_definition); 1004 return; 1005} 1006 1007/// DeclhasAttr - returns true if decl Declaration already has the target 1008/// attribute. 1009static bool 1010DeclHasAttr(const Decl *D, const Attr *A) { 1011 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1012 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1013 if ((*i)->getKind() == A->getKind()) { 1014 // FIXME: Don't hardcode this check 1015 if (OA && isa<OwnershipAttr>(*i)) 1016 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1017 return true; 1018 } 1019 1020 return false; 1021} 1022 1023/// MergeDeclAttributes - append attributes from the Old decl to the New one. 1024static void MergeDeclAttributes(Decl *New, Decl *Old, ASTContext &C) { 1025 if (!Old->hasAttrs()) 1026 return; 1027 // Ensure that any moving of objects within the allocated map is done before 1028 // we process them. 1029 if (!New->hasAttrs()) 1030 New->setAttrs(AttrVec()); 1031 for (Decl::attr_iterator i = Old->attr_begin(), e = Old->attr_end(); i != e; 1032 ++i) { 1033 // FIXME: Make this more general than just checking for Overloadable. 1034 if (!DeclHasAttr(New, *i) && (*i)->getKind() != attr::Overloadable) { 1035 Attr *NewAttr = (*i)->clone(C); 1036 NewAttr->setInherited(true); 1037 New->addAttr(NewAttr); 1038 } 1039 } 1040} 1041 1042namespace { 1043 1044/// Used in MergeFunctionDecl to keep track of function parameters in 1045/// C. 1046struct GNUCompatibleParamWarning { 1047 ParmVarDecl *OldParm; 1048 ParmVarDecl *NewParm; 1049 QualType PromotedType; 1050}; 1051 1052} 1053 1054/// getSpecialMember - get the special member enum for a method. 1055Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1056 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1057 if (Ctor->isCopyConstructor()) 1058 return Sema::CXXCopyConstructor; 1059 1060 return Sema::CXXConstructor; 1061 } 1062 1063 if (isa<CXXDestructorDecl>(MD)) 1064 return Sema::CXXDestructor; 1065 1066 assert(MD->isCopyAssignmentOperator() && 1067 "Must have copy assignment operator"); 1068 return Sema::CXXCopyAssignment; 1069} 1070 1071/// canRedefineFunction - checks if a function can be redefined. Currently, 1072/// only extern inline functions can be redefined, and even then only in 1073/// GNU89 mode. 1074static bool canRedefineFunction(const FunctionDecl *FD, 1075 const LangOptions& LangOpts) { 1076 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1077 FD->isInlineSpecified() && 1078 FD->getStorageClass() == SC_Extern); 1079} 1080 1081/// MergeFunctionDecl - We just parsed a function 'New' from 1082/// declarator D which has the same name and scope as a previous 1083/// declaration 'Old'. Figure out how to resolve this situation, 1084/// merging decls or emitting diagnostics as appropriate. 1085/// 1086/// In C++, New and Old must be declarations that are not 1087/// overloaded. Use IsOverload to determine whether New and Old are 1088/// overloaded, and to select the Old declaration that New should be 1089/// merged with. 1090/// 1091/// Returns true if there was an error, false otherwise. 1092bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1093 // Verify the old decl was also a function. 1094 FunctionDecl *Old = 0; 1095 if (FunctionTemplateDecl *OldFunctionTemplate 1096 = dyn_cast<FunctionTemplateDecl>(OldD)) 1097 Old = OldFunctionTemplate->getTemplatedDecl(); 1098 else 1099 Old = dyn_cast<FunctionDecl>(OldD); 1100 if (!Old) { 1101 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1102 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1103 Diag(Shadow->getTargetDecl()->getLocation(), 1104 diag::note_using_decl_target); 1105 Diag(Shadow->getUsingDecl()->getLocation(), 1106 diag::note_using_decl) << 0; 1107 return true; 1108 } 1109 1110 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1111 << New->getDeclName(); 1112 Diag(OldD->getLocation(), diag::note_previous_definition); 1113 return true; 1114 } 1115 1116 // Determine whether the previous declaration was a definition, 1117 // implicit declaration, or a declaration. 1118 diag::kind PrevDiag; 1119 if (Old->isThisDeclarationADefinition()) 1120 PrevDiag = diag::note_previous_definition; 1121 else if (Old->isImplicit()) 1122 PrevDiag = diag::note_previous_implicit_declaration; 1123 else 1124 PrevDiag = diag::note_previous_declaration; 1125 1126 QualType OldQType = Context.getCanonicalType(Old->getType()); 1127 QualType NewQType = Context.getCanonicalType(New->getType()); 1128 1129 // Don't complain about this if we're in GNU89 mode and the old function 1130 // is an extern inline function. 1131 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1132 New->getStorageClass() == SC_Static && 1133 Old->getStorageClass() != SC_Static && 1134 !canRedefineFunction(Old, getLangOptions())) { 1135 Diag(New->getLocation(), diag::err_static_non_static) 1136 << New; 1137 Diag(Old->getLocation(), PrevDiag); 1138 return true; 1139 } 1140 1141 // If a function is first declared with a calling convention, but is 1142 // later declared or defined without one, the second decl assumes the 1143 // calling convention of the first. 1144 // 1145 // For the new decl, we have to look at the NON-canonical type to tell the 1146 // difference between a function that really doesn't have a calling 1147 // convention and one that is declared cdecl. That's because in 1148 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1149 // because it is the default calling convention. 1150 // 1151 // Note also that we DO NOT return at this point, because we still have 1152 // other tests to run. 1153 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1154 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1155 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1156 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1157 if (OldTypeInfo.getCC() != CC_Default && 1158 NewTypeInfo.getCC() == CC_Default) { 1159 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1160 New->setType(NewQType); 1161 NewQType = Context.getCanonicalType(NewQType); 1162 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1163 NewTypeInfo.getCC())) { 1164 // Calling conventions really aren't compatible, so complain. 1165 Diag(New->getLocation(), diag::err_cconv_change) 1166 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1167 << (OldTypeInfo.getCC() == CC_Default) 1168 << (OldTypeInfo.getCC() == CC_Default ? "" : 1169 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1170 Diag(Old->getLocation(), diag::note_previous_declaration); 1171 return true; 1172 } 1173 1174 // FIXME: diagnose the other way around? 1175 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1176 NewQType = Context.getNoReturnType(NewQType); 1177 New->setType(NewQType); 1178 assert(NewQType.isCanonical()); 1179 } 1180 1181 // Merge regparm attribute. 1182 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1183 if (NewType->getRegParmType()) { 1184 Diag(New->getLocation(), diag::err_regparm_mismatch) 1185 << NewType->getRegParmType() 1186 << OldType->getRegParmType(); 1187 Diag(Old->getLocation(), diag::note_previous_declaration); 1188 return true; 1189 } 1190 1191 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1192 New->setType(NewQType); 1193 assert(NewQType.isCanonical()); 1194 } 1195 1196 if (getLangOptions().CPlusPlus) { 1197 // (C++98 13.1p2): 1198 // Certain function declarations cannot be overloaded: 1199 // -- Function declarations that differ only in the return type 1200 // cannot be overloaded. 1201 QualType OldReturnType 1202 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1203 QualType NewReturnType 1204 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1205 QualType ResQT; 1206 if (OldReturnType != NewReturnType) { 1207 if (NewReturnType->isObjCObjectPointerType() 1208 && OldReturnType->isObjCObjectPointerType()) 1209 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1210 if (ResQT.isNull()) { 1211 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1212 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1213 return true; 1214 } 1215 else 1216 NewQType = ResQT; 1217 } 1218 1219 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1220 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1221 if (OldMethod && NewMethod) { 1222 // Preserve triviality. 1223 NewMethod->setTrivial(OldMethod->isTrivial()); 1224 1225 bool isFriend = NewMethod->getFriendObjectKind(); 1226 1227 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1228 // -- Member function declarations with the same name and the 1229 // same parameter types cannot be overloaded if any of them 1230 // is a static member function declaration. 1231 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1232 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1233 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1234 return true; 1235 } 1236 1237 // C++ [class.mem]p1: 1238 // [...] A member shall not be declared twice in the 1239 // member-specification, except that a nested class or member 1240 // class template can be declared and then later defined. 1241 unsigned NewDiag; 1242 if (isa<CXXConstructorDecl>(OldMethod)) 1243 NewDiag = diag::err_constructor_redeclared; 1244 else if (isa<CXXDestructorDecl>(NewMethod)) 1245 NewDiag = diag::err_destructor_redeclared; 1246 else if (isa<CXXConversionDecl>(NewMethod)) 1247 NewDiag = diag::err_conv_function_redeclared; 1248 else 1249 NewDiag = diag::err_member_redeclared; 1250 1251 Diag(New->getLocation(), NewDiag); 1252 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1253 1254 // Complain if this is an explicit declaration of a special 1255 // member that was initially declared implicitly. 1256 // 1257 // As an exception, it's okay to befriend such methods in order 1258 // to permit the implicit constructor/destructor/operator calls. 1259 } else if (OldMethod->isImplicit()) { 1260 if (isFriend) { 1261 NewMethod->setImplicit(); 1262 } else { 1263 Diag(NewMethod->getLocation(), 1264 diag::err_definition_of_implicitly_declared_member) 1265 << New << getSpecialMember(OldMethod); 1266 return true; 1267 } 1268 } 1269 } 1270 1271 // (C++98 8.3.5p3): 1272 // All declarations for a function shall agree exactly in both the 1273 // return type and the parameter-type-list. 1274 // attributes should be ignored when comparing. 1275 if (Context.getNoReturnType(OldQType, false) == 1276 Context.getNoReturnType(NewQType, false)) 1277 return MergeCompatibleFunctionDecls(New, Old); 1278 1279 // Fall through for conflicting redeclarations and redefinitions. 1280 } 1281 1282 // C: Function types need to be compatible, not identical. This handles 1283 // duplicate function decls like "void f(int); void f(enum X);" properly. 1284 if (!getLangOptions().CPlusPlus && 1285 Context.typesAreCompatible(OldQType, NewQType)) { 1286 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1287 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1288 const FunctionProtoType *OldProto = 0; 1289 if (isa<FunctionNoProtoType>(NewFuncType) && 1290 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1291 // The old declaration provided a function prototype, but the 1292 // new declaration does not. Merge in the prototype. 1293 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1294 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1295 OldProto->arg_type_end()); 1296 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1297 ParamTypes.data(), ParamTypes.size(), 1298 OldProto->isVariadic(), 1299 OldProto->getTypeQuals(), 1300 false, false, 0, 0, 1301 OldProto->getExtInfo()); 1302 New->setType(NewQType); 1303 New->setHasInheritedPrototype(); 1304 1305 // Synthesize a parameter for each argument type. 1306 llvm::SmallVector<ParmVarDecl*, 16> Params; 1307 for (FunctionProtoType::arg_type_iterator 1308 ParamType = OldProto->arg_type_begin(), 1309 ParamEnd = OldProto->arg_type_end(); 1310 ParamType != ParamEnd; ++ParamType) { 1311 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1312 SourceLocation(), 0, 1313 *ParamType, /*TInfo=*/0, 1314 SC_None, SC_None, 1315 0); 1316 Param->setImplicit(); 1317 Params.push_back(Param); 1318 } 1319 1320 New->setParams(Params.data(), Params.size()); 1321 } 1322 1323 return MergeCompatibleFunctionDecls(New, Old); 1324 } 1325 1326 // GNU C permits a K&R definition to follow a prototype declaration 1327 // if the declared types of the parameters in the K&R definition 1328 // match the types in the prototype declaration, even when the 1329 // promoted types of the parameters from the K&R definition differ 1330 // from the types in the prototype. GCC then keeps the types from 1331 // the prototype. 1332 // 1333 // If a variadic prototype is followed by a non-variadic K&R definition, 1334 // the K&R definition becomes variadic. This is sort of an edge case, but 1335 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1336 // C99 6.9.1p8. 1337 if (!getLangOptions().CPlusPlus && 1338 Old->hasPrototype() && !New->hasPrototype() && 1339 New->getType()->getAs<FunctionProtoType>() && 1340 Old->getNumParams() == New->getNumParams()) { 1341 llvm::SmallVector<QualType, 16> ArgTypes; 1342 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1343 const FunctionProtoType *OldProto 1344 = Old->getType()->getAs<FunctionProtoType>(); 1345 const FunctionProtoType *NewProto 1346 = New->getType()->getAs<FunctionProtoType>(); 1347 1348 // Determine whether this is the GNU C extension. 1349 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1350 NewProto->getResultType()); 1351 bool LooseCompatible = !MergedReturn.isNull(); 1352 for (unsigned Idx = 0, End = Old->getNumParams(); 1353 LooseCompatible && Idx != End; ++Idx) { 1354 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1355 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1356 if (Context.typesAreCompatible(OldParm->getType(), 1357 NewProto->getArgType(Idx))) { 1358 ArgTypes.push_back(NewParm->getType()); 1359 } else if (Context.typesAreCompatible(OldParm->getType(), 1360 NewParm->getType(), 1361 /*CompareUnqualified=*/true)) { 1362 GNUCompatibleParamWarning Warn 1363 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1364 Warnings.push_back(Warn); 1365 ArgTypes.push_back(NewParm->getType()); 1366 } else 1367 LooseCompatible = false; 1368 } 1369 1370 if (LooseCompatible) { 1371 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1372 Diag(Warnings[Warn].NewParm->getLocation(), 1373 diag::ext_param_promoted_not_compatible_with_prototype) 1374 << Warnings[Warn].PromotedType 1375 << Warnings[Warn].OldParm->getType(); 1376 if (Warnings[Warn].OldParm->getLocation().isValid()) 1377 Diag(Warnings[Warn].OldParm->getLocation(), 1378 diag::note_previous_declaration); 1379 } 1380 1381 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1382 ArgTypes.size(), 1383 OldProto->isVariadic(), 0, 1384 false, false, 0, 0, 1385 OldProto->getExtInfo())); 1386 return MergeCompatibleFunctionDecls(New, Old); 1387 } 1388 1389 // Fall through to diagnose conflicting types. 1390 } 1391 1392 // A function that has already been declared has been redeclared or defined 1393 // with a different type- show appropriate diagnostic 1394 if (unsigned BuiltinID = Old->getBuiltinID()) { 1395 // The user has declared a builtin function with an incompatible 1396 // signature. 1397 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1398 // The function the user is redeclaring is a library-defined 1399 // function like 'malloc' or 'printf'. Warn about the 1400 // redeclaration, then pretend that we don't know about this 1401 // library built-in. 1402 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1403 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1404 << Old << Old->getType(); 1405 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1406 Old->setInvalidDecl(); 1407 return false; 1408 } 1409 1410 PrevDiag = diag::note_previous_builtin_declaration; 1411 } 1412 1413 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1414 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1415 return true; 1416} 1417 1418/// \brief Completes the merge of two function declarations that are 1419/// known to be compatible. 1420/// 1421/// This routine handles the merging of attributes and other 1422/// properties of function declarations form the old declaration to 1423/// the new declaration, once we know that New is in fact a 1424/// redeclaration of Old. 1425/// 1426/// \returns false 1427bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1428 // Merge the attributes 1429 MergeDeclAttributes(New, Old, Context); 1430 1431 // Merge the storage class. 1432 if (Old->getStorageClass() != SC_Extern && 1433 Old->getStorageClass() != SC_None) 1434 New->setStorageClass(Old->getStorageClass()); 1435 1436 // Merge "pure" flag. 1437 if (Old->isPure()) 1438 New->setPure(); 1439 1440 // Merge the "deleted" flag. 1441 if (Old->isDeleted()) 1442 New->setDeleted(); 1443 1444 if (getLangOptions().CPlusPlus) 1445 return MergeCXXFunctionDecl(New, Old); 1446 1447 return false; 1448} 1449 1450/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1451/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1452/// situation, merging decls or emitting diagnostics as appropriate. 1453/// 1454/// Tentative definition rules (C99 6.9.2p2) are checked by 1455/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1456/// definitions here, since the initializer hasn't been attached. 1457/// 1458void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1459 // If the new decl is already invalid, don't do any other checking. 1460 if (New->isInvalidDecl()) 1461 return; 1462 1463 // Verify the old decl was also a variable. 1464 VarDecl *Old = 0; 1465 if (!Previous.isSingleResult() || 1466 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1467 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1468 << New->getDeclName(); 1469 Diag(Previous.getRepresentativeDecl()->getLocation(), 1470 diag::note_previous_definition); 1471 return New->setInvalidDecl(); 1472 } 1473 1474 // C++ [class.mem]p1: 1475 // A member shall not be declared twice in the member-specification [...] 1476 // 1477 // Here, we need only consider static data members. 1478 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1479 Diag(New->getLocation(), diag::err_duplicate_member) 1480 << New->getIdentifier(); 1481 Diag(Old->getLocation(), diag::note_previous_declaration); 1482 New->setInvalidDecl(); 1483 } 1484 1485 MergeDeclAttributes(New, Old, Context); 1486 1487 // Merge the types 1488 QualType MergedT; 1489 if (getLangOptions().CPlusPlus) { 1490 if (Context.hasSameType(New->getType(), Old->getType())) 1491 MergedT = New->getType(); 1492 // C++ [basic.link]p10: 1493 // [...] the types specified by all declarations referring to a given 1494 // object or function shall be identical, except that declarations for an 1495 // array object can specify array types that differ by the presence or 1496 // absence of a major array bound (8.3.4). 1497 else if (Old->getType()->isIncompleteArrayType() && 1498 New->getType()->isArrayType()) { 1499 CanQual<ArrayType> OldArray 1500 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1501 CanQual<ArrayType> NewArray 1502 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1503 if (OldArray->getElementType() == NewArray->getElementType()) 1504 MergedT = New->getType(); 1505 } else if (Old->getType()->isArrayType() && 1506 New->getType()->isIncompleteArrayType()) { 1507 CanQual<ArrayType> OldArray 1508 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1509 CanQual<ArrayType> NewArray 1510 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1511 if (OldArray->getElementType() == NewArray->getElementType()) 1512 MergedT = Old->getType(); 1513 } else if (New->getType()->isObjCObjectPointerType() 1514 && Old->getType()->isObjCObjectPointerType()) { 1515 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1516 } 1517 } else { 1518 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1519 } 1520 if (MergedT.isNull()) { 1521 Diag(New->getLocation(), diag::err_redefinition_different_type) 1522 << New->getDeclName(); 1523 Diag(Old->getLocation(), diag::note_previous_definition); 1524 return New->setInvalidDecl(); 1525 } 1526 New->setType(MergedT); 1527 1528 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1529 if (New->getStorageClass() == SC_Static && 1530 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1531 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1532 Diag(Old->getLocation(), diag::note_previous_definition); 1533 return New->setInvalidDecl(); 1534 } 1535 // C99 6.2.2p4: 1536 // For an identifier declared with the storage-class specifier 1537 // extern in a scope in which a prior declaration of that 1538 // identifier is visible,23) if the prior declaration specifies 1539 // internal or external linkage, the linkage of the identifier at 1540 // the later declaration is the same as the linkage specified at 1541 // the prior declaration. If no prior declaration is visible, or 1542 // if the prior declaration specifies no linkage, then the 1543 // identifier has external linkage. 1544 if (New->hasExternalStorage() && Old->hasLinkage()) 1545 /* Okay */; 1546 else if (New->getStorageClass() != SC_Static && 1547 Old->getStorageClass() == SC_Static) { 1548 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1549 Diag(Old->getLocation(), diag::note_previous_definition); 1550 return New->setInvalidDecl(); 1551 } 1552 1553 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1554 1555 // FIXME: The test for external storage here seems wrong? We still 1556 // need to check for mismatches. 1557 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1558 // Don't complain about out-of-line definitions of static members. 1559 !(Old->getLexicalDeclContext()->isRecord() && 1560 !New->getLexicalDeclContext()->isRecord())) { 1561 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1562 Diag(Old->getLocation(), diag::note_previous_definition); 1563 return New->setInvalidDecl(); 1564 } 1565 1566 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1567 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1568 Diag(Old->getLocation(), diag::note_previous_definition); 1569 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1570 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1571 Diag(Old->getLocation(), diag::note_previous_definition); 1572 } 1573 1574 // C++ doesn't have tentative definitions, so go right ahead and check here. 1575 const VarDecl *Def; 1576 if (getLangOptions().CPlusPlus && 1577 New->isThisDeclarationADefinition() == VarDecl::Definition && 1578 (Def = Old->getDefinition())) { 1579 Diag(New->getLocation(), diag::err_redefinition) 1580 << New->getDeclName(); 1581 Diag(Def->getLocation(), diag::note_previous_definition); 1582 New->setInvalidDecl(); 1583 return; 1584 } 1585 // c99 6.2.2 P4. 1586 // For an identifier declared with the storage-class specifier extern in a 1587 // scope in which a prior declaration of that identifier is visible, if 1588 // the prior declaration specifies internal or external linkage, the linkage 1589 // of the identifier at the later declaration is the same as the linkage 1590 // specified at the prior declaration. 1591 // FIXME. revisit this code. 1592 if (New->hasExternalStorage() && 1593 Old->getLinkage() == InternalLinkage && 1594 New->getDeclContext() == Old->getDeclContext()) 1595 New->setStorageClass(Old->getStorageClass()); 1596 1597 // Keep a chain of previous declarations. 1598 New->setPreviousDeclaration(Old); 1599 1600 // Inherit access appropriately. 1601 New->setAccess(Old->getAccess()); 1602} 1603 1604/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1605/// no declarator (e.g. "struct foo;") is parsed. 1606Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1607 DeclSpec &DS) { 1608 // FIXME: Error on auto/register at file scope 1609 // FIXME: Error on inline/virtual/explicit 1610 // FIXME: Warn on useless __thread 1611 // FIXME: Warn on useless const/volatile 1612 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1613 // FIXME: Warn on useless attributes 1614 Decl *TagD = 0; 1615 TagDecl *Tag = 0; 1616 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1617 DS.getTypeSpecType() == DeclSpec::TST_struct || 1618 DS.getTypeSpecType() == DeclSpec::TST_union || 1619 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1620 TagD = DS.getRepAsDecl(); 1621 1622 if (!TagD) // We probably had an error 1623 return 0; 1624 1625 // Note that the above type specs guarantee that the 1626 // type rep is a Decl, whereas in many of the others 1627 // it's a Type. 1628 Tag = dyn_cast<TagDecl>(TagD); 1629 } 1630 1631 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1632 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1633 // or incomplete types shall not be restrict-qualified." 1634 if (TypeQuals & DeclSpec::TQ_restrict) 1635 Diag(DS.getRestrictSpecLoc(), 1636 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1637 << DS.getSourceRange(); 1638 } 1639 1640 if (DS.isFriendSpecified()) { 1641 // If we're dealing with a class template decl, assume that the 1642 // template routines are handling it. 1643 if (TagD && isa<ClassTemplateDecl>(TagD)) 1644 return 0; 1645 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1646 } 1647 1648 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1649 ProcessDeclAttributeList(S, Record, DS.getAttributes()); 1650 1651 if (!Record->getDeclName() && Record->isDefinition() && 1652 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1653 if (getLangOptions().CPlusPlus || 1654 Record->getDeclContext()->isRecord()) 1655 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1656 1657 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1658 << DS.getSourceRange(); 1659 } 1660 1661 // Microsoft allows unnamed struct/union fields. Don't complain 1662 // about them. 1663 // FIXME: Should we support Microsoft's extensions in this area? 1664 if (Record->getDeclName() && getLangOptions().Microsoft) 1665 return Tag; 1666 } 1667 1668 if (getLangOptions().CPlusPlus && 1669 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1670 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1671 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1672 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1673 Diag(Enum->getLocation(), diag::ext_no_declarators) 1674 << DS.getSourceRange(); 1675 1676 if (!DS.isMissingDeclaratorOk() && 1677 DS.getTypeSpecType() != DeclSpec::TST_error) { 1678 // Warn about typedefs of enums without names, since this is an 1679 // extension in both Microsoft and GNU. 1680 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1681 Tag && isa<EnumDecl>(Tag)) { 1682 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1683 << DS.getSourceRange(); 1684 return Tag; 1685 } 1686 1687 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1688 << DS.getSourceRange(); 1689 } 1690 1691 return TagD; 1692} 1693 1694/// We are trying to inject an anonymous member into the given scope; 1695/// check if there's an existing declaration that can't be overloaded. 1696/// 1697/// \return true if this is a forbidden redeclaration 1698static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1699 Scope *S, 1700 DeclContext *Owner, 1701 DeclarationName Name, 1702 SourceLocation NameLoc, 1703 unsigned diagnostic) { 1704 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1705 Sema::ForRedeclaration); 1706 if (!SemaRef.LookupName(R, S)) return false; 1707 1708 if (R.getAsSingle<TagDecl>()) 1709 return false; 1710 1711 // Pick a representative declaration. 1712 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1713 assert(PrevDecl && "Expected a non-null Decl"); 1714 1715 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1716 return false; 1717 1718 SemaRef.Diag(NameLoc, diagnostic) << Name; 1719 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1720 1721 return true; 1722} 1723 1724/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1725/// anonymous struct or union AnonRecord into the owning context Owner 1726/// and scope S. This routine will be invoked just after we realize 1727/// that an unnamed union or struct is actually an anonymous union or 1728/// struct, e.g., 1729/// 1730/// @code 1731/// union { 1732/// int i; 1733/// float f; 1734/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1735/// // f into the surrounding scope.x 1736/// @endcode 1737/// 1738/// This routine is recursive, injecting the names of nested anonymous 1739/// structs/unions into the owning context and scope as well. 1740static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1741 DeclContext *Owner, 1742 RecordDecl *AnonRecord, 1743 AccessSpecifier AS) { 1744 unsigned diagKind 1745 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1746 : diag::err_anonymous_struct_member_redecl; 1747 1748 bool Invalid = false; 1749 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1750 FEnd = AnonRecord->field_end(); 1751 F != FEnd; ++F) { 1752 if ((*F)->getDeclName()) { 1753 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1754 (*F)->getLocation(), diagKind)) { 1755 // C++ [class.union]p2: 1756 // The names of the members of an anonymous union shall be 1757 // distinct from the names of any other entity in the 1758 // scope in which the anonymous union is declared. 1759 Invalid = true; 1760 } else { 1761 // C++ [class.union]p2: 1762 // For the purpose of name lookup, after the anonymous union 1763 // definition, the members of the anonymous union are 1764 // considered to have been defined in the scope in which the 1765 // anonymous union is declared. 1766 Owner->makeDeclVisibleInContext(*F); 1767 S->AddDecl(*F); 1768 SemaRef.IdResolver.AddDecl(*F); 1769 1770 // That includes picking up the appropriate access specifier. 1771 if (AS != AS_none) (*F)->setAccess(AS); 1772 } 1773 } else if (const RecordType *InnerRecordType 1774 = (*F)->getType()->getAs<RecordType>()) { 1775 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1776 if (InnerRecord->isAnonymousStructOrUnion()) 1777 Invalid = Invalid || 1778 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1779 InnerRecord, AS); 1780 } 1781 } 1782 1783 return Invalid; 1784} 1785 1786/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1787/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1788/// illegal input values are mapped to SC_None. 1789static StorageClass 1790StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1791 switch (StorageClassSpec) { 1792 case DeclSpec::SCS_unspecified: return SC_None; 1793 case DeclSpec::SCS_extern: return SC_Extern; 1794 case DeclSpec::SCS_static: return SC_Static; 1795 case DeclSpec::SCS_auto: return SC_Auto; 1796 case DeclSpec::SCS_register: return SC_Register; 1797 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1798 // Illegal SCSs map to None: error reporting is up to the caller. 1799 case DeclSpec::SCS_mutable: // Fall through. 1800 case DeclSpec::SCS_typedef: return SC_None; 1801 } 1802 llvm_unreachable("unknown storage class specifier"); 1803} 1804 1805/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1806/// a StorageClass. Any error reporting is up to the caller: 1807/// illegal input values are mapped to SC_None. 1808static StorageClass 1809StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1810 switch (StorageClassSpec) { 1811 case DeclSpec::SCS_unspecified: return SC_None; 1812 case DeclSpec::SCS_extern: return SC_Extern; 1813 case DeclSpec::SCS_static: return SC_Static; 1814 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1815 // Illegal SCSs map to None: error reporting is up to the caller. 1816 case DeclSpec::SCS_auto: // Fall through. 1817 case DeclSpec::SCS_mutable: // Fall through. 1818 case DeclSpec::SCS_register: // Fall through. 1819 case DeclSpec::SCS_typedef: return SC_None; 1820 } 1821 llvm_unreachable("unknown storage class specifier"); 1822} 1823 1824/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1825/// anonymous structure or union. Anonymous unions are a C++ feature 1826/// (C++ [class.union]) and a GNU C extension; anonymous structures 1827/// are a GNU C and GNU C++ extension. 1828Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1829 AccessSpecifier AS, 1830 RecordDecl *Record) { 1831 DeclContext *Owner = Record->getDeclContext(); 1832 1833 // Diagnose whether this anonymous struct/union is an extension. 1834 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1835 Diag(Record->getLocation(), diag::ext_anonymous_union); 1836 else if (!Record->isUnion()) 1837 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1838 1839 // C and C++ require different kinds of checks for anonymous 1840 // structs/unions. 1841 bool Invalid = false; 1842 if (getLangOptions().CPlusPlus) { 1843 const char* PrevSpec = 0; 1844 unsigned DiagID; 1845 // C++ [class.union]p3: 1846 // Anonymous unions declared in a named namespace or in the 1847 // global namespace shall be declared static. 1848 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1849 (isa<TranslationUnitDecl>(Owner) || 1850 (isa<NamespaceDecl>(Owner) && 1851 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1852 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1853 Invalid = true; 1854 1855 // Recover by adding 'static'. 1856 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1857 PrevSpec, DiagID); 1858 } 1859 // C++ [class.union]p3: 1860 // A storage class is not allowed in a declaration of an 1861 // anonymous union in a class scope. 1862 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1863 isa<RecordDecl>(Owner)) { 1864 Diag(DS.getStorageClassSpecLoc(), 1865 diag::err_anonymous_union_with_storage_spec); 1866 Invalid = true; 1867 1868 // Recover by removing the storage specifier. 1869 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1870 PrevSpec, DiagID); 1871 } 1872 1873 // C++ [class.union]p2: 1874 // The member-specification of an anonymous union shall only 1875 // define non-static data members. [Note: nested types and 1876 // functions cannot be declared within an anonymous union. ] 1877 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1878 MemEnd = Record->decls_end(); 1879 Mem != MemEnd; ++Mem) { 1880 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1881 // C++ [class.union]p3: 1882 // An anonymous union shall not have private or protected 1883 // members (clause 11). 1884 assert(FD->getAccess() != AS_none); 1885 if (FD->getAccess() != AS_public) { 1886 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1887 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1888 Invalid = true; 1889 } 1890 1891 if (CheckNontrivialField(FD)) 1892 Invalid = true; 1893 } else if ((*Mem)->isImplicit()) { 1894 // Any implicit members are fine. 1895 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1896 // This is a type that showed up in an 1897 // elaborated-type-specifier inside the anonymous struct or 1898 // union, but which actually declares a type outside of the 1899 // anonymous struct or union. It's okay. 1900 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1901 if (!MemRecord->isAnonymousStructOrUnion() && 1902 MemRecord->getDeclName()) { 1903 // Visual C++ allows type definition in anonymous struct or union. 1904 if (getLangOptions().Microsoft) 1905 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 1906 << (int)Record->isUnion(); 1907 else { 1908 // This is a nested type declaration. 1909 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1910 << (int)Record->isUnion(); 1911 Invalid = true; 1912 } 1913 } 1914 } else if (isa<AccessSpecDecl>(*Mem)) { 1915 // Any access specifier is fine. 1916 } else { 1917 // We have something that isn't a non-static data 1918 // member. Complain about it. 1919 unsigned DK = diag::err_anonymous_record_bad_member; 1920 if (isa<TypeDecl>(*Mem)) 1921 DK = diag::err_anonymous_record_with_type; 1922 else if (isa<FunctionDecl>(*Mem)) 1923 DK = diag::err_anonymous_record_with_function; 1924 else if (isa<VarDecl>(*Mem)) 1925 DK = diag::err_anonymous_record_with_static; 1926 1927 // Visual C++ allows type definition in anonymous struct or union. 1928 if (getLangOptions().Microsoft && 1929 DK == diag::err_anonymous_record_with_type) 1930 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 1931 << (int)Record->isUnion(); 1932 else { 1933 Diag((*Mem)->getLocation(), DK) 1934 << (int)Record->isUnion(); 1935 Invalid = true; 1936 } 1937 } 1938 } 1939 } 1940 1941 if (!Record->isUnion() && !Owner->isRecord()) { 1942 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1943 << (int)getLangOptions().CPlusPlus; 1944 Invalid = true; 1945 } 1946 1947 // Mock up a declarator. 1948 Declarator Dc(DS, Declarator::TypeNameContext); 1949 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1950 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1951 1952 // Create a declaration for this anonymous struct/union. 1953 NamedDecl *Anon = 0; 1954 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1955 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1956 /*IdentifierInfo=*/0, 1957 Context.getTypeDeclType(Record), 1958 TInfo, 1959 /*BitWidth=*/0, /*Mutable=*/false); 1960 Anon->setAccess(AS); 1961 if (getLangOptions().CPlusPlus) { 1962 FieldCollector->Add(cast<FieldDecl>(Anon)); 1963 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1964 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1965 } 1966 } else { 1967 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1968 assert(SCSpec != DeclSpec::SCS_typedef && 1969 "Parser allowed 'typedef' as storage class VarDecl."); 1970 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1971 if (SCSpec == DeclSpec::SCS_mutable) { 1972 // mutable can only appear on non-static class members, so it's always 1973 // an error here 1974 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1975 Invalid = true; 1976 SC = SC_None; 1977 } 1978 SCSpec = DS.getStorageClassSpecAsWritten(); 1979 VarDecl::StorageClass SCAsWritten 1980 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1981 1982 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1983 /*IdentifierInfo=*/0, 1984 Context.getTypeDeclType(Record), 1985 TInfo, SC, SCAsWritten); 1986 } 1987 Anon->setImplicit(); 1988 1989 // Add the anonymous struct/union object to the current 1990 // context. We'll be referencing this object when we refer to one of 1991 // its members. 1992 Owner->addDecl(Anon); 1993 1994 // Inject the members of the anonymous struct/union into the owning 1995 // context and into the identifier resolver chain for name lookup 1996 // purposes. 1997 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1998 Invalid = true; 1999 2000 // Mark this as an anonymous struct/union type. Note that we do not 2001 // do this until after we have already checked and injected the 2002 // members of this anonymous struct/union type, because otherwise 2003 // the members could be injected twice: once by DeclContext when it 2004 // builds its lookup table, and once by 2005 // InjectAnonymousStructOrUnionMembers. 2006 Record->setAnonymousStructOrUnion(true); 2007 2008 if (Invalid) 2009 Anon->setInvalidDecl(); 2010 2011 return Anon; 2012} 2013 2014 2015/// GetNameForDeclarator - Determine the full declaration name for the 2016/// given Declarator. 2017DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2018 return GetNameFromUnqualifiedId(D.getName()); 2019} 2020 2021/// \brief Retrieves the declaration name from a parsed unqualified-id. 2022DeclarationNameInfo 2023Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2024 DeclarationNameInfo NameInfo; 2025 NameInfo.setLoc(Name.StartLocation); 2026 2027 switch (Name.getKind()) { 2028 2029 case UnqualifiedId::IK_Identifier: 2030 NameInfo.setName(Name.Identifier); 2031 NameInfo.setLoc(Name.StartLocation); 2032 return NameInfo; 2033 2034 case UnqualifiedId::IK_OperatorFunctionId: 2035 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2036 Name.OperatorFunctionId.Operator)); 2037 NameInfo.setLoc(Name.StartLocation); 2038 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2039 = Name.OperatorFunctionId.SymbolLocations[0]; 2040 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2041 = Name.EndLocation.getRawEncoding(); 2042 return NameInfo; 2043 2044 case UnqualifiedId::IK_LiteralOperatorId: 2045 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2046 Name.Identifier)); 2047 NameInfo.setLoc(Name.StartLocation); 2048 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2049 return NameInfo; 2050 2051 case UnqualifiedId::IK_ConversionFunctionId: { 2052 TypeSourceInfo *TInfo; 2053 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2054 if (Ty.isNull()) 2055 return DeclarationNameInfo(); 2056 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2057 Context.getCanonicalType(Ty))); 2058 NameInfo.setLoc(Name.StartLocation); 2059 NameInfo.setNamedTypeInfo(TInfo); 2060 return NameInfo; 2061 } 2062 2063 case UnqualifiedId::IK_ConstructorName: { 2064 TypeSourceInfo *TInfo; 2065 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2066 if (Ty.isNull()) 2067 return DeclarationNameInfo(); 2068 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2069 Context.getCanonicalType(Ty))); 2070 NameInfo.setLoc(Name.StartLocation); 2071 NameInfo.setNamedTypeInfo(TInfo); 2072 return NameInfo; 2073 } 2074 2075 case UnqualifiedId::IK_ConstructorTemplateId: { 2076 // In well-formed code, we can only have a constructor 2077 // template-id that refers to the current context, so go there 2078 // to find the actual type being constructed. 2079 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2080 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2081 return DeclarationNameInfo(); 2082 2083 // Determine the type of the class being constructed. 2084 QualType CurClassType = Context.getTypeDeclType(CurClass); 2085 2086 // FIXME: Check two things: that the template-id names the same type as 2087 // CurClassType, and that the template-id does not occur when the name 2088 // was qualified. 2089 2090 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2091 Context.getCanonicalType(CurClassType))); 2092 NameInfo.setLoc(Name.StartLocation); 2093 // FIXME: should we retrieve TypeSourceInfo? 2094 NameInfo.setNamedTypeInfo(0); 2095 return NameInfo; 2096 } 2097 2098 case UnqualifiedId::IK_DestructorName: { 2099 TypeSourceInfo *TInfo; 2100 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2101 if (Ty.isNull()) 2102 return DeclarationNameInfo(); 2103 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2104 Context.getCanonicalType(Ty))); 2105 NameInfo.setLoc(Name.StartLocation); 2106 NameInfo.setNamedTypeInfo(TInfo); 2107 return NameInfo; 2108 } 2109 2110 case UnqualifiedId::IK_TemplateId: { 2111 TemplateName TName = Name.TemplateId->Template.get(); 2112 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2113 return Context.getNameForTemplate(TName, TNameLoc); 2114 } 2115 2116 } // switch (Name.getKind()) 2117 2118 assert(false && "Unknown name kind"); 2119 return DeclarationNameInfo(); 2120} 2121 2122/// isNearlyMatchingFunction - Determine whether the C++ functions 2123/// Declaration and Definition are "nearly" matching. This heuristic 2124/// is used to improve diagnostics in the case where an out-of-line 2125/// function definition doesn't match any declaration within 2126/// the class or namespace. 2127static bool isNearlyMatchingFunction(ASTContext &Context, 2128 FunctionDecl *Declaration, 2129 FunctionDecl *Definition) { 2130 if (Declaration->param_size() != Definition->param_size()) 2131 return false; 2132 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2133 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2134 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2135 2136 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2137 DefParamTy.getNonReferenceType())) 2138 return false; 2139 } 2140 2141 return true; 2142} 2143 2144/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2145/// declarator needs to be rebuilt in the current instantiation. 2146/// Any bits of declarator which appear before the name are valid for 2147/// consideration here. That's specifically the type in the decl spec 2148/// and the base type in any member-pointer chunks. 2149static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2150 DeclarationName Name) { 2151 // The types we specifically need to rebuild are: 2152 // - typenames, typeofs, and decltypes 2153 // - types which will become injected class names 2154 // Of course, we also need to rebuild any type referencing such a 2155 // type. It's safest to just say "dependent", but we call out a 2156 // few cases here. 2157 2158 DeclSpec &DS = D.getMutableDeclSpec(); 2159 switch (DS.getTypeSpecType()) { 2160 case DeclSpec::TST_typename: 2161 case DeclSpec::TST_typeofType: 2162 case DeclSpec::TST_decltype: { 2163 // Grab the type from the parser. 2164 TypeSourceInfo *TSI = 0; 2165 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2166 if (T.isNull() || !T->isDependentType()) break; 2167 2168 // Make sure there's a type source info. This isn't really much 2169 // of a waste; most dependent types should have type source info 2170 // attached already. 2171 if (!TSI) 2172 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2173 2174 // Rebuild the type in the current instantiation. 2175 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2176 if (!TSI) return true; 2177 2178 // Store the new type back in the decl spec. 2179 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2180 DS.UpdateTypeRep(LocType); 2181 break; 2182 } 2183 2184 case DeclSpec::TST_typeofExpr: { 2185 Expr *E = DS.getRepAsExpr(); 2186 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2187 if (Result.isInvalid()) return true; 2188 DS.UpdateExprRep(Result.get()); 2189 break; 2190 } 2191 2192 default: 2193 // Nothing to do for these decl specs. 2194 break; 2195 } 2196 2197 // It doesn't matter what order we do this in. 2198 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2199 DeclaratorChunk &Chunk = D.getTypeObject(I); 2200 2201 // The only type information in the declarator which can come 2202 // before the declaration name is the base type of a member 2203 // pointer. 2204 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2205 continue; 2206 2207 // Rebuild the scope specifier in-place. 2208 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2209 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2210 return true; 2211 } 2212 2213 return false; 2214} 2215 2216Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2217 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2218} 2219 2220Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2221 MultiTemplateParamsArg TemplateParamLists, 2222 bool IsFunctionDefinition) { 2223 // TODO: consider using NameInfo for diagnostic. 2224 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2225 DeclarationName Name = NameInfo.getName(); 2226 2227 // All of these full declarators require an identifier. If it doesn't have 2228 // one, the ParsedFreeStandingDeclSpec action should be used. 2229 if (!Name) { 2230 if (!D.isInvalidType()) // Reject this if we think it is valid. 2231 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2232 diag::err_declarator_need_ident) 2233 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2234 return 0; 2235 } 2236 2237 // The scope passed in may not be a decl scope. Zip up the scope tree until 2238 // we find one that is. 2239 while ((S->getFlags() & Scope::DeclScope) == 0 || 2240 (S->getFlags() & Scope::TemplateParamScope) != 0) 2241 S = S->getParent(); 2242 2243 DeclContext *DC = CurContext; 2244 if (D.getCXXScopeSpec().isInvalid()) 2245 D.setInvalidType(); 2246 else if (D.getCXXScopeSpec().isSet()) { 2247 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2248 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2249 if (!DC) { 2250 // If we could not compute the declaration context, it's because the 2251 // declaration context is dependent but does not refer to a class, 2252 // class template, or class template partial specialization. Complain 2253 // and return early, to avoid the coming semantic disaster. 2254 Diag(D.getIdentifierLoc(), 2255 diag::err_template_qualified_declarator_no_match) 2256 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2257 << D.getCXXScopeSpec().getRange(); 2258 return 0; 2259 } 2260 2261 bool IsDependentContext = DC->isDependentContext(); 2262 2263 if (!IsDependentContext && 2264 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2265 return 0; 2266 2267 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2268 Diag(D.getIdentifierLoc(), 2269 diag::err_member_def_undefined_record) 2270 << Name << DC << D.getCXXScopeSpec().getRange(); 2271 D.setInvalidType(); 2272 } 2273 2274 // Check whether we need to rebuild the type of the given 2275 // declaration in the current instantiation. 2276 if (EnteringContext && IsDependentContext && 2277 TemplateParamLists.size() != 0) { 2278 ContextRAII SavedContext(*this, DC); 2279 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2280 D.setInvalidType(); 2281 } 2282 } 2283 2284 NamedDecl *New; 2285 2286 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2287 QualType R = TInfo->getType(); 2288 2289 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2290 ForRedeclaration); 2291 2292 // See if this is a redefinition of a variable in the same scope. 2293 if (!D.getCXXScopeSpec().isSet()) { 2294 bool IsLinkageLookup = false; 2295 2296 // If the declaration we're planning to build will be a function 2297 // or object with linkage, then look for another declaration with 2298 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2299 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2300 /* Do nothing*/; 2301 else if (R->isFunctionType()) { 2302 if (CurContext->isFunctionOrMethod() || 2303 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2304 IsLinkageLookup = true; 2305 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2306 IsLinkageLookup = true; 2307 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2308 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2309 IsLinkageLookup = true; 2310 2311 if (IsLinkageLookup) 2312 Previous.clear(LookupRedeclarationWithLinkage); 2313 2314 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2315 } else { // Something like "int foo::x;" 2316 LookupQualifiedName(Previous, DC); 2317 2318 // Don't consider using declarations as previous declarations for 2319 // out-of-line members. 2320 RemoveUsingDecls(Previous); 2321 2322 // C++ 7.3.1.2p2: 2323 // Members (including explicit specializations of templates) of a named 2324 // namespace can also be defined outside that namespace by explicit 2325 // qualification of the name being defined, provided that the entity being 2326 // defined was already declared in the namespace and the definition appears 2327 // after the point of declaration in a namespace that encloses the 2328 // declarations namespace. 2329 // 2330 // Note that we only check the context at this point. We don't yet 2331 // have enough information to make sure that PrevDecl is actually 2332 // the declaration we want to match. For example, given: 2333 // 2334 // class X { 2335 // void f(); 2336 // void f(float); 2337 // }; 2338 // 2339 // void X::f(int) { } // ill-formed 2340 // 2341 // In this case, PrevDecl will point to the overload set 2342 // containing the two f's declared in X, but neither of them 2343 // matches. 2344 2345 // First check whether we named the global scope. 2346 if (isa<TranslationUnitDecl>(DC)) { 2347 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2348 << Name << D.getCXXScopeSpec().getRange(); 2349 } else { 2350 DeclContext *Cur = CurContext; 2351 while (isa<LinkageSpecDecl>(Cur)) 2352 Cur = Cur->getParent(); 2353 if (!Cur->Encloses(DC)) { 2354 // The qualifying scope doesn't enclose the original declaration. 2355 // Emit diagnostic based on current scope. 2356 SourceLocation L = D.getIdentifierLoc(); 2357 SourceRange R = D.getCXXScopeSpec().getRange(); 2358 if (isa<FunctionDecl>(Cur)) 2359 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2360 else 2361 Diag(L, diag::err_invalid_declarator_scope) 2362 << Name << cast<NamedDecl>(DC) << R; 2363 D.setInvalidType(); 2364 } 2365 } 2366 } 2367 2368 if (Previous.isSingleResult() && 2369 Previous.getFoundDecl()->isTemplateParameter()) { 2370 // Maybe we will complain about the shadowed template parameter. 2371 if (!D.isInvalidType()) 2372 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2373 Previous.getFoundDecl())) 2374 D.setInvalidType(); 2375 2376 // Just pretend that we didn't see the previous declaration. 2377 Previous.clear(); 2378 } 2379 2380 // In C++, the previous declaration we find might be a tag type 2381 // (class or enum). In this case, the new declaration will hide the 2382 // tag type. Note that this does does not apply if we're declaring a 2383 // typedef (C++ [dcl.typedef]p4). 2384 if (Previous.isSingleTagDecl() && 2385 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2386 Previous.clear(); 2387 2388 bool Redeclaration = false; 2389 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2390 if (TemplateParamLists.size()) { 2391 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2392 return 0; 2393 } 2394 2395 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2396 } else if (R->isFunctionType()) { 2397 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2398 move(TemplateParamLists), 2399 IsFunctionDefinition, Redeclaration); 2400 } else { 2401 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2402 move(TemplateParamLists), 2403 Redeclaration); 2404 } 2405 2406 if (New == 0) 2407 return 0; 2408 2409 // If this has an identifier and is not an invalid redeclaration or 2410 // function template specialization, add it to the scope stack. 2411 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2412 PushOnScopeChains(New, S); 2413 2414 return New; 2415} 2416 2417/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2418/// types into constant array types in certain situations which would otherwise 2419/// be errors (for GCC compatibility). 2420static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2421 ASTContext &Context, 2422 bool &SizeIsNegative, 2423 llvm::APSInt &Oversized) { 2424 // This method tries to turn a variable array into a constant 2425 // array even when the size isn't an ICE. This is necessary 2426 // for compatibility with code that depends on gcc's buggy 2427 // constant expression folding, like struct {char x[(int)(char*)2];} 2428 SizeIsNegative = false; 2429 Oversized = 0; 2430 2431 if (T->isDependentType()) 2432 return QualType(); 2433 2434 QualifierCollector Qs; 2435 const Type *Ty = Qs.strip(T); 2436 2437 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2438 QualType Pointee = PTy->getPointeeType(); 2439 QualType FixedType = 2440 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2441 Oversized); 2442 if (FixedType.isNull()) return FixedType; 2443 FixedType = Context.getPointerType(FixedType); 2444 return Qs.apply(FixedType); 2445 } 2446 2447 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2448 if (!VLATy) 2449 return QualType(); 2450 // FIXME: We should probably handle this case 2451 if (VLATy->getElementType()->isVariablyModifiedType()) 2452 return QualType(); 2453 2454 Expr::EvalResult EvalResult; 2455 if (!VLATy->getSizeExpr() || 2456 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2457 !EvalResult.Val.isInt()) 2458 return QualType(); 2459 2460 // Check whether the array size is negative. 2461 llvm::APSInt &Res = EvalResult.Val.getInt(); 2462 if (Res.isSigned() && Res.isNegative()) { 2463 SizeIsNegative = true; 2464 return QualType(); 2465 } 2466 2467 // Check whether the array is too large to be addressed. 2468 unsigned ActiveSizeBits 2469 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2470 Res); 2471 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2472 Oversized = Res; 2473 return QualType(); 2474 } 2475 2476 return Context.getConstantArrayType(VLATy->getElementType(), 2477 Res, ArrayType::Normal, 0); 2478} 2479 2480/// \brief Register the given locally-scoped external C declaration so 2481/// that it can be found later for redeclarations 2482void 2483Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2484 const LookupResult &Previous, 2485 Scope *S) { 2486 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2487 "Decl is not a locally-scoped decl!"); 2488 // Note that we have a locally-scoped external with this name. 2489 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2490 2491 if (!Previous.isSingleResult()) 2492 return; 2493 2494 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2495 2496 // If there was a previous declaration of this variable, it may be 2497 // in our identifier chain. Update the identifier chain with the new 2498 // declaration. 2499 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2500 // The previous declaration was found on the identifer resolver 2501 // chain, so remove it from its scope. 2502 while (S && !S->isDeclScope(PrevDecl)) 2503 S = S->getParent(); 2504 2505 if (S) 2506 S->RemoveDecl(PrevDecl); 2507 } 2508} 2509 2510/// \brief Diagnose function specifiers on a declaration of an identifier that 2511/// does not identify a function. 2512void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2513 // FIXME: We should probably indicate the identifier in question to avoid 2514 // confusion for constructs like "inline int a(), b;" 2515 if (D.getDeclSpec().isInlineSpecified()) 2516 Diag(D.getDeclSpec().getInlineSpecLoc(), 2517 diag::err_inline_non_function); 2518 2519 if (D.getDeclSpec().isVirtualSpecified()) 2520 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2521 diag::err_virtual_non_function); 2522 2523 if (D.getDeclSpec().isExplicitSpecified()) 2524 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2525 diag::err_explicit_non_function); 2526} 2527 2528NamedDecl* 2529Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2530 QualType R, TypeSourceInfo *TInfo, 2531 LookupResult &Previous, bool &Redeclaration) { 2532 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2533 if (D.getCXXScopeSpec().isSet()) { 2534 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2535 << D.getCXXScopeSpec().getRange(); 2536 D.setInvalidType(); 2537 // Pretend we didn't see the scope specifier. 2538 DC = CurContext; 2539 Previous.clear(); 2540 } 2541 2542 if (getLangOptions().CPlusPlus) { 2543 // Check that there are no default arguments (C++ only). 2544 CheckExtraCXXDefaultArguments(D); 2545 } 2546 2547 DiagnoseFunctionSpecifiers(D); 2548 2549 if (D.getDeclSpec().isThreadSpecified()) 2550 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2551 2552 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2553 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2554 << D.getName().getSourceRange(); 2555 return 0; 2556 } 2557 2558 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2559 if (!NewTD) return 0; 2560 2561 // Handle attributes prior to checking for duplicates in MergeVarDecl 2562 ProcessDeclAttributes(S, NewTD, D); 2563 2564 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2565 // then it shall have block scope. 2566 // Note that variably modified types must be fixed before merging the decl so 2567 // that redeclarations will match. 2568 QualType T = NewTD->getUnderlyingType(); 2569 if (T->isVariablyModifiedType()) { 2570 getCurFunction()->setHasBranchProtectedScope(); 2571 2572 if (S->getFnParent() == 0) { 2573 bool SizeIsNegative; 2574 llvm::APSInt Oversized; 2575 QualType FixedTy = 2576 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2577 Oversized); 2578 if (!FixedTy.isNull()) { 2579 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2580 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2581 } else { 2582 if (SizeIsNegative) 2583 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2584 else if (T->isVariableArrayType()) 2585 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2586 else if (Oversized.getBoolValue()) 2587 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2588 << Oversized.toString(10); 2589 else 2590 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2591 NewTD->setInvalidDecl(); 2592 } 2593 } 2594 } 2595 2596 // Merge the decl with the existing one if appropriate. If the decl is 2597 // in an outer scope, it isn't the same thing. 2598 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2599 if (!Previous.empty()) { 2600 Redeclaration = true; 2601 MergeTypeDefDecl(NewTD, Previous); 2602 } 2603 2604 // If this is the C FILE type, notify the AST context. 2605 if (IdentifierInfo *II = NewTD->getIdentifier()) 2606 if (!NewTD->isInvalidDecl() && 2607 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2608 if (II->isStr("FILE")) 2609 Context.setFILEDecl(NewTD); 2610 else if (II->isStr("jmp_buf")) 2611 Context.setjmp_bufDecl(NewTD); 2612 else if (II->isStr("sigjmp_buf")) 2613 Context.setsigjmp_bufDecl(NewTD); 2614 } 2615 2616 return NewTD; 2617} 2618 2619/// \brief Determines whether the given declaration is an out-of-scope 2620/// previous declaration. 2621/// 2622/// This routine should be invoked when name lookup has found a 2623/// previous declaration (PrevDecl) that is not in the scope where a 2624/// new declaration by the same name is being introduced. If the new 2625/// declaration occurs in a local scope, previous declarations with 2626/// linkage may still be considered previous declarations (C99 2627/// 6.2.2p4-5, C++ [basic.link]p6). 2628/// 2629/// \param PrevDecl the previous declaration found by name 2630/// lookup 2631/// 2632/// \param DC the context in which the new declaration is being 2633/// declared. 2634/// 2635/// \returns true if PrevDecl is an out-of-scope previous declaration 2636/// for a new delcaration with the same name. 2637static bool 2638isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2639 ASTContext &Context) { 2640 if (!PrevDecl) 2641 return false; 2642 2643 if (!PrevDecl->hasLinkage()) 2644 return false; 2645 2646 if (Context.getLangOptions().CPlusPlus) { 2647 // C++ [basic.link]p6: 2648 // If there is a visible declaration of an entity with linkage 2649 // having the same name and type, ignoring entities declared 2650 // outside the innermost enclosing namespace scope, the block 2651 // scope declaration declares that same entity and receives the 2652 // linkage of the previous declaration. 2653 DeclContext *OuterContext = DC->getRedeclContext(); 2654 if (!OuterContext->isFunctionOrMethod()) 2655 // This rule only applies to block-scope declarations. 2656 return false; 2657 2658 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2659 if (PrevOuterContext->isRecord()) 2660 // We found a member function: ignore it. 2661 return false; 2662 2663 // Find the innermost enclosing namespace for the new and 2664 // previous declarations. 2665 OuterContext = OuterContext->getEnclosingNamespaceContext(); 2666 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 2667 2668 // The previous declaration is in a different namespace, so it 2669 // isn't the same function. 2670 if (!OuterContext->Equals(PrevOuterContext)) 2671 return false; 2672 } 2673 2674 return true; 2675} 2676 2677static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2678 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2679 if (!SS.isSet()) return; 2680 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2681 SS.getRange()); 2682} 2683 2684NamedDecl* 2685Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2686 QualType R, TypeSourceInfo *TInfo, 2687 LookupResult &Previous, 2688 MultiTemplateParamsArg TemplateParamLists, 2689 bool &Redeclaration) { 2690 DeclarationName Name = GetNameForDeclarator(D).getName(); 2691 2692 // Check that there are no default arguments (C++ only). 2693 if (getLangOptions().CPlusPlus) 2694 CheckExtraCXXDefaultArguments(D); 2695 2696 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2697 assert(SCSpec != DeclSpec::SCS_typedef && 2698 "Parser allowed 'typedef' as storage class VarDecl."); 2699 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2700 if (SCSpec == DeclSpec::SCS_mutable) { 2701 // mutable can only appear on non-static class members, so it's always 2702 // an error here 2703 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2704 D.setInvalidType(); 2705 SC = SC_None; 2706 } 2707 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2708 VarDecl::StorageClass SCAsWritten 2709 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2710 2711 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2712 if (!II) { 2713 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2714 << Name.getAsString(); 2715 return 0; 2716 } 2717 2718 DiagnoseFunctionSpecifiers(D); 2719 2720 if (!DC->isRecord() && S->getFnParent() == 0) { 2721 // C99 6.9p2: The storage-class specifiers auto and register shall not 2722 // appear in the declaration specifiers in an external declaration. 2723 if (SC == SC_Auto || SC == SC_Register) { 2724 2725 // If this is a register variable with an asm label specified, then this 2726 // is a GNU extension. 2727 if (SC == SC_Register && D.getAsmLabel()) 2728 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2729 else 2730 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2731 D.setInvalidType(); 2732 } 2733 } 2734 if (DC->isRecord() && !CurContext->isRecord()) { 2735 // This is an out-of-line definition of a static data member. 2736 if (SC == SC_Static) { 2737 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2738 diag::err_static_out_of_line) 2739 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2740 } else if (SC == SC_None) 2741 SC = SC_Static; 2742 } 2743 if (SC == SC_Static) { 2744 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2745 if (RD->isLocalClass()) 2746 Diag(D.getIdentifierLoc(), 2747 diag::err_static_data_member_not_allowed_in_local_class) 2748 << Name << RD->getDeclName(); 2749 } 2750 } 2751 2752 // Match up the template parameter lists with the scope specifier, then 2753 // determine whether we have a template or a template specialization. 2754 bool isExplicitSpecialization = false; 2755 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2756 bool Invalid = false; 2757 if (TemplateParameterList *TemplateParams 2758 = MatchTemplateParametersToScopeSpecifier( 2759 D.getDeclSpec().getSourceRange().getBegin(), 2760 D.getCXXScopeSpec(), 2761 (TemplateParameterList**)TemplateParamLists.get(), 2762 TemplateParamLists.size(), 2763 /*never a friend*/ false, 2764 isExplicitSpecialization, 2765 Invalid)) { 2766 // All but one template parameter lists have been matching. 2767 --NumMatchedTemplateParamLists; 2768 2769 if (TemplateParams->size() > 0) { 2770 // There is no such thing as a variable template. 2771 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2772 << II 2773 << SourceRange(TemplateParams->getTemplateLoc(), 2774 TemplateParams->getRAngleLoc()); 2775 return 0; 2776 } else { 2777 // There is an extraneous 'template<>' for this variable. Complain 2778 // about it, but allow the declaration of the variable. 2779 Diag(TemplateParams->getTemplateLoc(), 2780 diag::err_template_variable_noparams) 2781 << II 2782 << SourceRange(TemplateParams->getTemplateLoc(), 2783 TemplateParams->getRAngleLoc()); 2784 2785 isExplicitSpecialization = true; 2786 } 2787 } 2788 2789 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2790 II, R, TInfo, SC, SCAsWritten); 2791 2792 if (D.isInvalidType() || Invalid) 2793 NewVD->setInvalidDecl(); 2794 2795 SetNestedNameSpecifier(NewVD, D); 2796 2797 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2798 NewVD->setTemplateParameterListsInfo(Context, 2799 NumMatchedTemplateParamLists, 2800 (TemplateParameterList**)TemplateParamLists.release()); 2801 } 2802 2803 if (D.getDeclSpec().isThreadSpecified()) { 2804 if (NewVD->hasLocalStorage()) 2805 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2806 else if (!Context.Target.isTLSSupported()) 2807 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2808 else 2809 NewVD->setThreadSpecified(true); 2810 } 2811 2812 // Set the lexical context. If the declarator has a C++ scope specifier, the 2813 // lexical context will be different from the semantic context. 2814 NewVD->setLexicalDeclContext(CurContext); 2815 2816 // Handle attributes prior to checking for duplicates in MergeVarDecl 2817 ProcessDeclAttributes(S, NewVD, D); 2818 2819 // Handle GNU asm-label extension (encoded as an attribute). 2820 if (Expr *E = (Expr*) D.getAsmLabel()) { 2821 // The parser guarantees this is a string. 2822 StringLiteral *SE = cast<StringLiteral>(E); 2823 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2824 Context, SE->getString())); 2825 } 2826 2827 // Diagnose shadowed variables before filtering for scope. 2828 if (!D.getCXXScopeSpec().isSet()) 2829 CheckShadow(S, NewVD, Previous); 2830 2831 // Don't consider existing declarations that are in a different 2832 // scope and are out-of-semantic-context declarations (if the new 2833 // declaration has linkage). 2834 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2835 2836 // Merge the decl with the existing one if appropriate. 2837 if (!Previous.empty()) { 2838 if (Previous.isSingleResult() && 2839 isa<FieldDecl>(Previous.getFoundDecl()) && 2840 D.getCXXScopeSpec().isSet()) { 2841 // The user tried to define a non-static data member 2842 // out-of-line (C++ [dcl.meaning]p1). 2843 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2844 << D.getCXXScopeSpec().getRange(); 2845 Previous.clear(); 2846 NewVD->setInvalidDecl(); 2847 } 2848 } else if (D.getCXXScopeSpec().isSet()) { 2849 // No previous declaration in the qualifying scope. 2850 Diag(D.getIdentifierLoc(), diag::err_no_member) 2851 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2852 << D.getCXXScopeSpec().getRange(); 2853 NewVD->setInvalidDecl(); 2854 } 2855 2856 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2857 2858 // This is an explicit specialization of a static data member. Check it. 2859 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2860 CheckMemberSpecialization(NewVD, Previous)) 2861 NewVD->setInvalidDecl(); 2862 2863 // attributes declared post-definition are currently ignored 2864 // FIXME: This should be handled in attribute merging, not 2865 // here. 2866 if (Previous.isSingleResult()) { 2867 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2868 if (Def && (Def = Def->getDefinition()) && 2869 Def != NewVD && D.hasAttributes()) { 2870 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2871 Diag(Def->getLocation(), diag::note_previous_definition); 2872 } 2873 } 2874 2875 // If this is a locally-scoped extern C variable, update the map of 2876 // such variables. 2877 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2878 !NewVD->isInvalidDecl()) 2879 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2880 2881 // If there's a #pragma GCC visibility in scope, and this isn't a class 2882 // member, set the visibility of this variable. 2883 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2884 AddPushedVisibilityAttribute(NewVD); 2885 2886 MarkUnusedFileScopedDecl(NewVD); 2887 2888 return NewVD; 2889} 2890 2891/// \brief Diagnose variable or built-in function shadowing. Implements 2892/// -Wshadow. 2893/// 2894/// This method is called whenever a VarDecl is added to a "useful" 2895/// scope. 2896/// 2897/// \param S the scope in which the shadowing name is being declared 2898/// \param R the lookup of the name 2899/// 2900void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2901 // Return if warning is ignored. 2902 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2903 return; 2904 2905 // Don't diagnose declarations at file scope. The scope might not 2906 // have a DeclContext if (e.g.) we're parsing a function prototype. 2907 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2908 if (NewDC && NewDC->isFileContext()) 2909 return; 2910 2911 // Only diagnose if we're shadowing an unambiguous field or variable. 2912 if (R.getResultKind() != LookupResult::Found) 2913 return; 2914 2915 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2916 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2917 return; 2918 2919 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2920 2921 // Only warn about certain kinds of shadowing for class members. 2922 if (NewDC && NewDC->isRecord()) { 2923 // In particular, don't warn about shadowing non-class members. 2924 if (!OldDC->isRecord()) 2925 return; 2926 2927 // TODO: should we warn about static data members shadowing 2928 // static data members from base classes? 2929 2930 // TODO: don't diagnose for inaccessible shadowed members. 2931 // This is hard to do perfectly because we might friend the 2932 // shadowing context, but that's just a false negative. 2933 } 2934 2935 // Determine what kind of declaration we're shadowing. 2936 unsigned Kind; 2937 if (isa<RecordDecl>(OldDC)) { 2938 if (isa<FieldDecl>(ShadowedDecl)) 2939 Kind = 3; // field 2940 else 2941 Kind = 2; // static data member 2942 } else if (OldDC->isFileContext()) 2943 Kind = 1; // global 2944 else 2945 Kind = 0; // local 2946 2947 DeclarationName Name = R.getLookupName(); 2948 2949 // Emit warning and note. 2950 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2951 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2952} 2953 2954/// \brief Check -Wshadow without the advantage of a previous lookup. 2955void Sema::CheckShadow(Scope *S, VarDecl *D) { 2956 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2957 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2958 LookupName(R, S); 2959 CheckShadow(S, D, R); 2960} 2961 2962/// \brief Perform semantic checking on a newly-created variable 2963/// declaration. 2964/// 2965/// This routine performs all of the type-checking required for a 2966/// variable declaration once it has been built. It is used both to 2967/// check variables after they have been parsed and their declarators 2968/// have been translated into a declaration, and to check variables 2969/// that have been instantiated from a template. 2970/// 2971/// Sets NewVD->isInvalidDecl() if an error was encountered. 2972void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2973 LookupResult &Previous, 2974 bool &Redeclaration) { 2975 // If the decl is already known invalid, don't check it. 2976 if (NewVD->isInvalidDecl()) 2977 return; 2978 2979 QualType T = NewVD->getType(); 2980 2981 if (T->isObjCObjectType()) { 2982 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2983 return NewVD->setInvalidDecl(); 2984 } 2985 2986 // Emit an error if an address space was applied to decl with local storage. 2987 // This includes arrays of objects with address space qualifiers, but not 2988 // automatic variables that point to other address spaces. 2989 // ISO/IEC TR 18037 S5.1.2 2990 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2991 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2992 return NewVD->setInvalidDecl(); 2993 } 2994 2995 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2996 && !NewVD->hasAttr<BlocksAttr>()) 2997 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2998 2999 bool isVM = T->isVariablyModifiedType(); 3000 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3001 NewVD->hasAttr<BlocksAttr>()) 3002 getCurFunction()->setHasBranchProtectedScope(); 3003 3004 if ((isVM && NewVD->hasLinkage()) || 3005 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3006 bool SizeIsNegative; 3007 llvm::APSInt Oversized; 3008 QualType FixedTy = 3009 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3010 Oversized); 3011 3012 if (FixedTy.isNull() && T->isVariableArrayType()) { 3013 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3014 // FIXME: This won't give the correct result for 3015 // int a[10][n]; 3016 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3017 3018 if (NewVD->isFileVarDecl()) 3019 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3020 << SizeRange; 3021 else if (NewVD->getStorageClass() == SC_Static) 3022 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3023 << SizeRange; 3024 else 3025 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3026 << SizeRange; 3027 return NewVD->setInvalidDecl(); 3028 } 3029 3030 if (FixedTy.isNull()) { 3031 if (NewVD->isFileVarDecl()) 3032 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3033 else 3034 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3035 return NewVD->setInvalidDecl(); 3036 } 3037 3038 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3039 NewVD->setType(FixedTy); 3040 } 3041 3042 if (Previous.empty() && NewVD->isExternC()) { 3043 // Since we did not find anything by this name and we're declaring 3044 // an extern "C" variable, look for a non-visible extern "C" 3045 // declaration with the same name. 3046 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3047 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3048 if (Pos != LocallyScopedExternalDecls.end()) 3049 Previous.addDecl(Pos->second); 3050 } 3051 3052 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3053 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3054 << T; 3055 return NewVD->setInvalidDecl(); 3056 } 3057 3058 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3059 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3060 return NewVD->setInvalidDecl(); 3061 } 3062 3063 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3064 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3065 return NewVD->setInvalidDecl(); 3066 } 3067 3068 // Function pointers and references cannot have qualified function type, only 3069 // function pointer-to-members can do that. 3070 QualType Pointee; 3071 unsigned PtrOrRef = 0; 3072 if (const PointerType *Ptr = T->getAs<PointerType>()) 3073 Pointee = Ptr->getPointeeType(); 3074 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3075 Pointee = Ref->getPointeeType(); 3076 PtrOrRef = 1; 3077 } 3078 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3079 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3080 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3081 << PtrOrRef; 3082 return NewVD->setInvalidDecl(); 3083 } 3084 3085 if (!Previous.empty()) { 3086 Redeclaration = true; 3087 MergeVarDecl(NewVD, Previous); 3088 } 3089} 3090 3091/// \brief Data used with FindOverriddenMethod 3092struct FindOverriddenMethodData { 3093 Sema *S; 3094 CXXMethodDecl *Method; 3095}; 3096 3097/// \brief Member lookup function that determines whether a given C++ 3098/// method overrides a method in a base class, to be used with 3099/// CXXRecordDecl::lookupInBases(). 3100static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3101 CXXBasePath &Path, 3102 void *UserData) { 3103 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3104 3105 FindOverriddenMethodData *Data 3106 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3107 3108 DeclarationName Name = Data->Method->getDeclName(); 3109 3110 // FIXME: Do we care about other names here too? 3111 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3112 // We really want to find the base class destructor here. 3113 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3114 CanQualType CT = Data->S->Context.getCanonicalType(T); 3115 3116 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3117 } 3118 3119 for (Path.Decls = BaseRecord->lookup(Name); 3120 Path.Decls.first != Path.Decls.second; 3121 ++Path.Decls.first) { 3122 NamedDecl *D = *Path.Decls.first; 3123 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3124 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3125 return true; 3126 } 3127 } 3128 3129 return false; 3130} 3131 3132/// AddOverriddenMethods - See if a method overrides any in the base classes, 3133/// and if so, check that it's a valid override and remember it. 3134void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3135 // Look for virtual methods in base classes that this method might override. 3136 CXXBasePaths Paths; 3137 FindOverriddenMethodData Data; 3138 Data.Method = MD; 3139 Data.S = this; 3140 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3141 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3142 E = Paths.found_decls_end(); I != E; ++I) { 3143 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3144 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3145 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3146 !CheckOverridingFunctionAttributes(MD, OldMD)) 3147 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3148 } 3149 } 3150 } 3151} 3152 3153NamedDecl* 3154Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3155 QualType R, TypeSourceInfo *TInfo, 3156 LookupResult &Previous, 3157 MultiTemplateParamsArg TemplateParamLists, 3158 bool IsFunctionDefinition, bool &Redeclaration) { 3159 assert(R.getTypePtr()->isFunctionType()); 3160 3161 // TODO: consider using NameInfo for diagnostic. 3162 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3163 DeclarationName Name = NameInfo.getName(); 3164 FunctionDecl::StorageClass SC = SC_None; 3165 switch (D.getDeclSpec().getStorageClassSpec()) { 3166 default: assert(0 && "Unknown storage class!"); 3167 case DeclSpec::SCS_auto: 3168 case DeclSpec::SCS_register: 3169 case DeclSpec::SCS_mutable: 3170 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3171 diag::err_typecheck_sclass_func); 3172 D.setInvalidType(); 3173 break; 3174 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3175 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3176 case DeclSpec::SCS_static: { 3177 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3178 // C99 6.7.1p5: 3179 // The declaration of an identifier for a function that has 3180 // block scope shall have no explicit storage-class specifier 3181 // other than extern 3182 // See also (C++ [dcl.stc]p4). 3183 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3184 diag::err_static_block_func); 3185 SC = SC_None; 3186 } else 3187 SC = SC_Static; 3188 break; 3189 } 3190 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3191 } 3192 3193 if (D.getDeclSpec().isThreadSpecified()) 3194 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3195 3196 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3197 bool isInline = D.getDeclSpec().isInlineSpecified(); 3198 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3199 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3200 3201 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3202 FunctionDecl::StorageClass SCAsWritten 3203 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3204 3205 // Check that the return type is not an abstract class type. 3206 // For record types, this is done by the AbstractClassUsageDiagnoser once 3207 // the class has been completely parsed. 3208 if (!DC->isRecord() && 3209 RequireNonAbstractType(D.getIdentifierLoc(), 3210 R->getAs<FunctionType>()->getResultType(), 3211 diag::err_abstract_type_in_decl, 3212 AbstractReturnType)) 3213 D.setInvalidType(); 3214 3215 // Do not allow returning a objc interface by-value. 3216 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3217 Diag(D.getIdentifierLoc(), 3218 diag::err_object_cannot_be_passed_returned_by_value) << 0 3219 << R->getAs<FunctionType>()->getResultType(); 3220 D.setInvalidType(); 3221 } 3222 3223 bool isVirtualOkay = false; 3224 FunctionDecl *NewFD; 3225 3226 if (isFriend) { 3227 // C++ [class.friend]p5 3228 // A function can be defined in a friend declaration of a 3229 // class . . . . Such a function is implicitly inline. 3230 isInline |= IsFunctionDefinition; 3231 } 3232 3233 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3234 // This is a C++ constructor declaration. 3235 assert(DC->isRecord() && 3236 "Constructors can only be declared in a member context"); 3237 3238 R = CheckConstructorDeclarator(D, R, SC); 3239 3240 // Create the new declaration 3241 NewFD = CXXConstructorDecl::Create(Context, 3242 cast<CXXRecordDecl>(DC), 3243 NameInfo, R, TInfo, 3244 isExplicit, isInline, 3245 /*isImplicitlyDeclared=*/false); 3246 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3247 // This is a C++ destructor declaration. 3248 if (DC->isRecord()) { 3249 R = CheckDestructorDeclarator(D, R, SC); 3250 3251 NewFD = CXXDestructorDecl::Create(Context, 3252 cast<CXXRecordDecl>(DC), 3253 NameInfo, R, 3254 isInline, 3255 /*isImplicitlyDeclared=*/false); 3256 NewFD->setTypeSourceInfo(TInfo); 3257 3258 isVirtualOkay = true; 3259 } else { 3260 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3261 3262 // Create a FunctionDecl to satisfy the function definition parsing 3263 // code path. 3264 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3265 Name, R, TInfo, SC, SCAsWritten, isInline, 3266 /*hasPrototype=*/true); 3267 D.setInvalidType(); 3268 } 3269 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3270 if (!DC->isRecord()) { 3271 Diag(D.getIdentifierLoc(), 3272 diag::err_conv_function_not_member); 3273 return 0; 3274 } 3275 3276 CheckConversionDeclarator(D, R, SC); 3277 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3278 NameInfo, R, TInfo, 3279 isInline, isExplicit); 3280 3281 isVirtualOkay = true; 3282 } else if (DC->isRecord()) { 3283 // If the of the function is the same as the name of the record, then this 3284 // must be an invalid constructor that has a return type. 3285 // (The parser checks for a return type and makes the declarator a 3286 // constructor if it has no return type). 3287 // must have an invalid constructor that has a return type 3288 if (Name.getAsIdentifierInfo() && 3289 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3290 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3291 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3292 << SourceRange(D.getIdentifierLoc()); 3293 return 0; 3294 } 3295 3296 bool isStatic = SC == SC_Static; 3297 3298 // [class.free]p1: 3299 // Any allocation function for a class T is a static member 3300 // (even if not explicitly declared static). 3301 if (Name.getCXXOverloadedOperator() == OO_New || 3302 Name.getCXXOverloadedOperator() == OO_Array_New) 3303 isStatic = true; 3304 3305 // [class.free]p6 Any deallocation function for a class X is a static member 3306 // (even if not explicitly declared static). 3307 if (Name.getCXXOverloadedOperator() == OO_Delete || 3308 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3309 isStatic = true; 3310 3311 // This is a C++ method declaration. 3312 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3313 NameInfo, R, TInfo, 3314 isStatic, SCAsWritten, isInline); 3315 3316 isVirtualOkay = !isStatic; 3317 } else { 3318 // Determine whether the function was written with a 3319 // prototype. This true when: 3320 // - we're in C++ (where every function has a prototype), 3321 // - there is a prototype in the declarator, or 3322 // - the type R of the function is some kind of typedef or other reference 3323 // to a type name (which eventually refers to a function type). 3324 bool HasPrototype = 3325 getLangOptions().CPlusPlus || 3326 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3327 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3328 3329 NewFD = FunctionDecl::Create(Context, DC, 3330 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3331 HasPrototype); 3332 } 3333 3334 if (D.isInvalidType()) 3335 NewFD->setInvalidDecl(); 3336 3337 SetNestedNameSpecifier(NewFD, D); 3338 3339 // Set the lexical context. If the declarator has a C++ 3340 // scope specifier, or is the object of a friend declaration, the 3341 // lexical context will be different from the semantic context. 3342 NewFD->setLexicalDeclContext(CurContext); 3343 3344 // Match up the template parameter lists with the scope specifier, then 3345 // determine whether we have a template or a template specialization. 3346 FunctionTemplateDecl *FunctionTemplate = 0; 3347 bool isExplicitSpecialization = false; 3348 bool isFunctionTemplateSpecialization = false; 3349 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3350 bool Invalid = false; 3351 if (TemplateParameterList *TemplateParams 3352 = MatchTemplateParametersToScopeSpecifier( 3353 D.getDeclSpec().getSourceRange().getBegin(), 3354 D.getCXXScopeSpec(), 3355 (TemplateParameterList**)TemplateParamLists.get(), 3356 TemplateParamLists.size(), 3357 isFriend, 3358 isExplicitSpecialization, 3359 Invalid)) { 3360 // All but one template parameter lists have been matching. 3361 --NumMatchedTemplateParamLists; 3362 3363 if (TemplateParams->size() > 0) { 3364 // This is a function template 3365 3366 // Check that we can declare a template here. 3367 if (CheckTemplateDeclScope(S, TemplateParams)) 3368 return 0; 3369 3370 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3371 NewFD->getLocation(), 3372 Name, TemplateParams, 3373 NewFD); 3374 FunctionTemplate->setLexicalDeclContext(CurContext); 3375 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3376 } else { 3377 // This is a function template specialization. 3378 isFunctionTemplateSpecialization = true; 3379 3380 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3381 if (isFriend && isFunctionTemplateSpecialization) { 3382 // We want to remove the "template<>", found here. 3383 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3384 3385 // If we remove the template<> and the name is not a 3386 // template-id, we're actually silently creating a problem: 3387 // the friend declaration will refer to an untemplated decl, 3388 // and clearly the user wants a template specialization. So 3389 // we need to insert '<>' after the name. 3390 SourceLocation InsertLoc; 3391 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3392 InsertLoc = D.getName().getSourceRange().getEnd(); 3393 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3394 } 3395 3396 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3397 << Name << RemoveRange 3398 << FixItHint::CreateRemoval(RemoveRange) 3399 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3400 } 3401 } 3402 } 3403 3404 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3405 NewFD->setTemplateParameterListsInfo(Context, 3406 NumMatchedTemplateParamLists, 3407 (TemplateParameterList**)TemplateParamLists.release()); 3408 } 3409 3410 if (Invalid) { 3411 NewFD->setInvalidDecl(); 3412 if (FunctionTemplate) 3413 FunctionTemplate->setInvalidDecl(); 3414 } 3415 3416 // C++ [dcl.fct.spec]p5: 3417 // The virtual specifier shall only be used in declarations of 3418 // nonstatic class member functions that appear within a 3419 // member-specification of a class declaration; see 10.3. 3420 // 3421 if (isVirtual && !NewFD->isInvalidDecl()) { 3422 if (!isVirtualOkay) { 3423 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3424 diag::err_virtual_non_function); 3425 } else if (!CurContext->isRecord()) { 3426 // 'virtual' was specified outside of the class. 3427 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3428 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3429 } else { 3430 // Okay: Add virtual to the method. 3431 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3432 CurClass->setMethodAsVirtual(NewFD); 3433 } 3434 } 3435 3436 // C++ [dcl.fct.spec]p3: 3437 // The inline specifier shall not appear on a block scope function declaration. 3438 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3439 if (CurContext->isFunctionOrMethod()) { 3440 // 'inline' is not allowed on block scope function declaration. 3441 Diag(D.getDeclSpec().getInlineSpecLoc(), 3442 diag::err_inline_declaration_block_scope) << Name 3443 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3444 } 3445 } 3446 3447 // C++ [dcl.fct.spec]p6: 3448 // The explicit specifier shall be used only in the declaration of a 3449 // constructor or conversion function within its class definition; see 12.3.1 3450 // and 12.3.2. 3451 if (isExplicit && !NewFD->isInvalidDecl()) { 3452 if (!CurContext->isRecord()) { 3453 // 'explicit' was specified outside of the class. 3454 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3455 diag::err_explicit_out_of_class) 3456 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3457 } else if (!isa<CXXConstructorDecl>(NewFD) && 3458 !isa<CXXConversionDecl>(NewFD)) { 3459 // 'explicit' was specified on a function that wasn't a constructor 3460 // or conversion function. 3461 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3462 diag::err_explicit_non_ctor_or_conv_function) 3463 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3464 } 3465 } 3466 3467 // Filter out previous declarations that don't match the scope. 3468 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3469 3470 if (isFriend) { 3471 // DC is the namespace in which the function is being declared. 3472 assert((DC->isFileContext() || !Previous.empty()) && 3473 "previously-undeclared friend function being created " 3474 "in a non-namespace context"); 3475 3476 // For now, claim that the objects have no previous declaration. 3477 if (FunctionTemplate) { 3478 FunctionTemplate->setObjectOfFriendDecl(false); 3479 FunctionTemplate->setAccess(AS_public); 3480 } 3481 NewFD->setObjectOfFriendDecl(false); 3482 NewFD->setAccess(AS_public); 3483 } 3484 3485 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3486 !CurContext->isRecord()) { 3487 // C++ [class.static]p1: 3488 // A data or function member of a class may be declared static 3489 // in a class definition, in which case it is a static member of 3490 // the class. 3491 3492 // Complain about the 'static' specifier if it's on an out-of-line 3493 // member function definition. 3494 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3495 diag::err_static_out_of_line) 3496 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3497 } 3498 3499 // Handle GNU asm-label extension (encoded as an attribute). 3500 if (Expr *E = (Expr*) D.getAsmLabel()) { 3501 // The parser guarantees this is a string. 3502 StringLiteral *SE = cast<StringLiteral>(E); 3503 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3504 SE->getString())); 3505 } 3506 3507 // Copy the parameter declarations from the declarator D to the function 3508 // declaration NewFD, if they are available. First scavenge them into Params. 3509 llvm::SmallVector<ParmVarDecl*, 16> Params; 3510 if (D.getNumTypeObjects() > 0) { 3511 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3512 3513 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3514 // function that takes no arguments, not a function that takes a 3515 // single void argument. 3516 // We let through "const void" here because Sema::GetTypeForDeclarator 3517 // already checks for that case. 3518 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3519 FTI.ArgInfo[0].Param && 3520 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3521 // Empty arg list, don't push any params. 3522 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3523 3524 // In C++, the empty parameter-type-list must be spelled "void"; a 3525 // typedef of void is not permitted. 3526 if (getLangOptions().CPlusPlus && 3527 Param->getType().getUnqualifiedType() != Context.VoidTy) 3528 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3529 // FIXME: Leaks decl? 3530 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3531 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3532 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3533 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3534 Param->setDeclContext(NewFD); 3535 Params.push_back(Param); 3536 3537 if (Param->isInvalidDecl()) 3538 NewFD->setInvalidDecl(); 3539 } 3540 } 3541 3542 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3543 // When we're declaring a function with a typedef, typeof, etc as in the 3544 // following example, we'll need to synthesize (unnamed) 3545 // parameters for use in the declaration. 3546 // 3547 // @code 3548 // typedef void fn(int); 3549 // fn f; 3550 // @endcode 3551 3552 // Synthesize a parameter for each argument type. 3553 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3554 AE = FT->arg_type_end(); AI != AE; ++AI) { 3555 ParmVarDecl *Param = 3556 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3557 Params.push_back(Param); 3558 } 3559 } else { 3560 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3561 "Should not need args for typedef of non-prototype fn"); 3562 } 3563 // Finally, we know we have the right number of parameters, install them. 3564 NewFD->setParams(Params.data(), Params.size()); 3565 3566 // If the declarator is a template-id, translate the parser's template 3567 // argument list into our AST format. 3568 bool HasExplicitTemplateArgs = false; 3569 TemplateArgumentListInfo TemplateArgs; 3570 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3571 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3572 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3573 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3574 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3575 TemplateId->getTemplateArgs(), 3576 TemplateId->NumArgs); 3577 translateTemplateArguments(TemplateArgsPtr, 3578 TemplateArgs); 3579 TemplateArgsPtr.release(); 3580 3581 HasExplicitTemplateArgs = true; 3582 3583 if (FunctionTemplate) { 3584 // FIXME: Diagnose function template with explicit template 3585 // arguments. 3586 HasExplicitTemplateArgs = false; 3587 } else if (!isFunctionTemplateSpecialization && 3588 !D.getDeclSpec().isFriendSpecified()) { 3589 // We have encountered something that the user meant to be a 3590 // specialization (because it has explicitly-specified template 3591 // arguments) but that was not introduced with a "template<>" (or had 3592 // too few of them). 3593 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3594 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3595 << FixItHint::CreateInsertion( 3596 D.getDeclSpec().getSourceRange().getBegin(), 3597 "template<> "); 3598 isFunctionTemplateSpecialization = true; 3599 } else { 3600 // "friend void foo<>(int);" is an implicit specialization decl. 3601 isFunctionTemplateSpecialization = true; 3602 } 3603 } else if (isFriend && isFunctionTemplateSpecialization) { 3604 // This combination is only possible in a recovery case; the user 3605 // wrote something like: 3606 // template <> friend void foo(int); 3607 // which we're recovering from as if the user had written: 3608 // friend void foo<>(int); 3609 // Go ahead and fake up a template id. 3610 HasExplicitTemplateArgs = true; 3611 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3612 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3613 } 3614 3615 // If it's a friend (and only if it's a friend), it's possible 3616 // that either the specialized function type or the specialized 3617 // template is dependent, and therefore matching will fail. In 3618 // this case, don't check the specialization yet. 3619 if (isFunctionTemplateSpecialization && isFriend && 3620 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3621 assert(HasExplicitTemplateArgs && 3622 "friend function specialization without template args"); 3623 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3624 Previous)) 3625 NewFD->setInvalidDecl(); 3626 } else if (isFunctionTemplateSpecialization) { 3627 if (CheckFunctionTemplateSpecialization(NewFD, 3628 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3629 Previous)) 3630 NewFD->setInvalidDecl(); 3631 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3632 if (CheckMemberSpecialization(NewFD, Previous)) 3633 NewFD->setInvalidDecl(); 3634 } 3635 3636 // Perform semantic checking on the function declaration. 3637 bool OverloadableAttrRequired = false; // FIXME: HACK! 3638 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3639 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3640 3641 assert((NewFD->isInvalidDecl() || !Redeclaration || 3642 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3643 "previous declaration set still overloaded"); 3644 3645 NamedDecl *PrincipalDecl = (FunctionTemplate 3646 ? cast<NamedDecl>(FunctionTemplate) 3647 : NewFD); 3648 3649 if (isFriend && Redeclaration) { 3650 AccessSpecifier Access = AS_public; 3651 if (!NewFD->isInvalidDecl()) 3652 Access = NewFD->getPreviousDeclaration()->getAccess(); 3653 3654 NewFD->setAccess(Access); 3655 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3656 3657 PrincipalDecl->setObjectOfFriendDecl(true); 3658 } 3659 3660 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3661 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3662 PrincipalDecl->setNonMemberOperator(); 3663 3664 // If we have a function template, check the template parameter 3665 // list. This will check and merge default template arguments. 3666 if (FunctionTemplate) { 3667 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3668 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3669 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3670 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3671 : TPC_FunctionTemplate); 3672 } 3673 3674 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3675 // Fake up an access specifier if it's supposed to be a class member. 3676 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3677 NewFD->setAccess(AS_public); 3678 3679 // An out-of-line member function declaration must also be a 3680 // definition (C++ [dcl.meaning]p1). 3681 // Note that this is not the case for explicit specializations of 3682 // function templates or member functions of class templates, per 3683 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3684 // for compatibility with old SWIG code which likes to generate them. 3685 if (!IsFunctionDefinition && !isFriend && 3686 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3687 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3688 << D.getCXXScopeSpec().getRange(); 3689 } 3690 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3691 // The user tried to provide an out-of-line definition for a 3692 // function that is a member of a class or namespace, but there 3693 // was no such member function declared (C++ [class.mfct]p2, 3694 // C++ [namespace.memdef]p2). For example: 3695 // 3696 // class X { 3697 // void f() const; 3698 // }; 3699 // 3700 // void X::f() { } // ill-formed 3701 // 3702 // Complain about this problem, and attempt to suggest close 3703 // matches (e.g., those that differ only in cv-qualifiers and 3704 // whether the parameter types are references). 3705 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3706 << Name << DC << D.getCXXScopeSpec().getRange(); 3707 NewFD->setInvalidDecl(); 3708 3709 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3710 ForRedeclaration); 3711 LookupQualifiedName(Prev, DC); 3712 assert(!Prev.isAmbiguous() && 3713 "Cannot have an ambiguity in previous-declaration lookup"); 3714 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3715 Func != FuncEnd; ++Func) { 3716 if (isa<FunctionDecl>(*Func) && 3717 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3718 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3719 } 3720 } 3721 } 3722 3723 // Handle attributes. We need to have merged decls when handling attributes 3724 // (for example to check for conflicts, etc). 3725 // FIXME: This needs to happen before we merge declarations. Then, 3726 // let attribute merging cope with attribute conflicts. 3727 ProcessDeclAttributes(S, NewFD, D); 3728 3729 // attributes declared post-definition are currently ignored 3730 // FIXME: This should happen during attribute merging 3731 if (Redeclaration && Previous.isSingleResult()) { 3732 const FunctionDecl *Def; 3733 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3734 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3735 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3736 Diag(Def->getLocation(), diag::note_previous_definition); 3737 } 3738 } 3739 3740 AddKnownFunctionAttributes(NewFD); 3741 3742 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3743 // If a function name is overloadable in C, then every function 3744 // with that name must be marked "overloadable". 3745 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3746 << Redeclaration << NewFD; 3747 if (!Previous.empty()) 3748 Diag(Previous.getRepresentativeDecl()->getLocation(), 3749 diag::note_attribute_overloadable_prev_overload); 3750 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3751 } 3752 3753 if (NewFD->hasAttr<OverloadableAttr>() && 3754 !NewFD->getType()->getAs<FunctionProtoType>()) { 3755 Diag(NewFD->getLocation(), 3756 diag::err_attribute_overloadable_no_prototype) 3757 << NewFD; 3758 3759 // Turn this into a variadic function with no parameters. 3760 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3761 QualType R = Context.getFunctionType(FT->getResultType(), 3762 0, 0, true, 0, false, false, 0, 0, 3763 FT->getExtInfo()); 3764 NewFD->setType(R); 3765 } 3766 3767 // If there's a #pragma GCC visibility in scope, and this isn't a class 3768 // member, set the visibility of this function. 3769 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3770 AddPushedVisibilityAttribute(NewFD); 3771 3772 // If this is a locally-scoped extern C function, update the 3773 // map of such names. 3774 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3775 && !NewFD->isInvalidDecl()) 3776 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3777 3778 // Set this FunctionDecl's range up to the right paren. 3779 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3780 3781 if (FunctionTemplate && NewFD->isInvalidDecl()) 3782 FunctionTemplate->setInvalidDecl(); 3783 3784 if (FunctionTemplate) 3785 return FunctionTemplate; 3786 3787 MarkUnusedFileScopedDecl(NewFD); 3788 3789 return NewFD; 3790} 3791 3792/// \brief Perform semantic checking of a new function declaration. 3793/// 3794/// Performs semantic analysis of the new function declaration 3795/// NewFD. This routine performs all semantic checking that does not 3796/// require the actual declarator involved in the declaration, and is 3797/// used both for the declaration of functions as they are parsed 3798/// (called via ActOnDeclarator) and for the declaration of functions 3799/// that have been instantiated via C++ template instantiation (called 3800/// via InstantiateDecl). 3801/// 3802/// \param IsExplicitSpecialiation whether this new function declaration is 3803/// an explicit specialization of the previous declaration. 3804/// 3805/// This sets NewFD->isInvalidDecl() to true if there was an error. 3806void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3807 LookupResult &Previous, 3808 bool IsExplicitSpecialization, 3809 bool &Redeclaration, 3810 bool &OverloadableAttrRequired) { 3811 // If NewFD is already known erroneous, don't do any of this checking. 3812 if (NewFD->isInvalidDecl()) { 3813 // If this is a class member, mark the class invalid immediately. 3814 // This avoids some consistency errors later. 3815 if (isa<CXXMethodDecl>(NewFD)) 3816 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3817 3818 return; 3819 } 3820 3821 if (NewFD->getResultType()->isVariablyModifiedType()) { 3822 // Functions returning a variably modified type violate C99 6.7.5.2p2 3823 // because all functions have linkage. 3824 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3825 return NewFD->setInvalidDecl(); 3826 } 3827 3828 if (NewFD->isMain()) 3829 CheckMain(NewFD); 3830 3831 // Check for a previous declaration of this name. 3832 if (Previous.empty() && NewFD->isExternC()) { 3833 // Since we did not find anything by this name and we're declaring 3834 // an extern "C" function, look for a non-visible extern "C" 3835 // declaration with the same name. 3836 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3837 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3838 if (Pos != LocallyScopedExternalDecls.end()) 3839 Previous.addDecl(Pos->second); 3840 } 3841 3842 // Merge or overload the declaration with an existing declaration of 3843 // the same name, if appropriate. 3844 if (!Previous.empty()) { 3845 // Determine whether NewFD is an overload of PrevDecl or 3846 // a declaration that requires merging. If it's an overload, 3847 // there's no more work to do here; we'll just add the new 3848 // function to the scope. 3849 3850 NamedDecl *OldDecl = 0; 3851 if (!AllowOverloadingOfFunction(Previous, Context)) { 3852 Redeclaration = true; 3853 OldDecl = Previous.getFoundDecl(); 3854 } else { 3855 if (!getLangOptions().CPlusPlus) 3856 OverloadableAttrRequired = true; 3857 3858 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3859 /*NewIsUsingDecl*/ false)) { 3860 case Ovl_Match: 3861 Redeclaration = true; 3862 break; 3863 3864 case Ovl_NonFunction: 3865 Redeclaration = true; 3866 break; 3867 3868 case Ovl_Overload: 3869 Redeclaration = false; 3870 break; 3871 } 3872 } 3873 3874 if (Redeclaration) { 3875 // NewFD and OldDecl represent declarations that need to be 3876 // merged. 3877 if (MergeFunctionDecl(NewFD, OldDecl)) 3878 return NewFD->setInvalidDecl(); 3879 3880 Previous.clear(); 3881 Previous.addDecl(OldDecl); 3882 3883 if (FunctionTemplateDecl *OldTemplateDecl 3884 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3885 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3886 FunctionTemplateDecl *NewTemplateDecl 3887 = NewFD->getDescribedFunctionTemplate(); 3888 assert(NewTemplateDecl && "Template/non-template mismatch"); 3889 if (CXXMethodDecl *Method 3890 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3891 Method->setAccess(OldTemplateDecl->getAccess()); 3892 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3893 } 3894 3895 // If this is an explicit specialization of a member that is a function 3896 // template, mark it as a member specialization. 3897 if (IsExplicitSpecialization && 3898 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3899 NewTemplateDecl->setMemberSpecialization(); 3900 assert(OldTemplateDecl->isMemberSpecialization()); 3901 } 3902 } else { 3903 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3904 NewFD->setAccess(OldDecl->getAccess()); 3905 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3906 } 3907 } 3908 } 3909 3910 // Semantic checking for this function declaration (in isolation). 3911 if (getLangOptions().CPlusPlus) { 3912 // C++-specific checks. 3913 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3914 CheckConstructor(Constructor); 3915 } else if (CXXDestructorDecl *Destructor = 3916 dyn_cast<CXXDestructorDecl>(NewFD)) { 3917 CXXRecordDecl *Record = Destructor->getParent(); 3918 QualType ClassType = Context.getTypeDeclType(Record); 3919 3920 // FIXME: Shouldn't we be able to perform this check even when the class 3921 // type is dependent? Both gcc and edg can handle that. 3922 if (!ClassType->isDependentType()) { 3923 DeclarationName Name 3924 = Context.DeclarationNames.getCXXDestructorName( 3925 Context.getCanonicalType(ClassType)); 3926// NewFD->getDeclName().dump(); 3927// Name.dump(); 3928 if (NewFD->getDeclName() != Name) { 3929 Diag(NewFD->getLocation(), diag::err_destructor_name); 3930 return NewFD->setInvalidDecl(); 3931 } 3932 } 3933 3934 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3935 // user-defined destructor. 3936 Record->setPOD(false); 3937 3938 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3939 // declared destructor. 3940 // FIXME: C++0x: don't do this for "= default" destructors 3941 Record->setHasTrivialDestructor(false); 3942 } else if (CXXConversionDecl *Conversion 3943 = dyn_cast<CXXConversionDecl>(NewFD)) { 3944 ActOnConversionDeclarator(Conversion); 3945 } 3946 3947 // Find any virtual functions that this function overrides. 3948 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3949 if (!Method->isFunctionTemplateSpecialization() && 3950 !Method->getDescribedFunctionTemplate()) 3951 AddOverriddenMethods(Method->getParent(), Method); 3952 } 3953 3954 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3955 if (NewFD->isOverloadedOperator() && 3956 CheckOverloadedOperatorDeclaration(NewFD)) 3957 return NewFD->setInvalidDecl(); 3958 3959 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3960 if (NewFD->getLiteralIdentifier() && 3961 CheckLiteralOperatorDeclaration(NewFD)) 3962 return NewFD->setInvalidDecl(); 3963 3964 // In C++, check default arguments now that we have merged decls. Unless 3965 // the lexical context is the class, because in this case this is done 3966 // during delayed parsing anyway. 3967 if (!CurContext->isRecord()) 3968 CheckCXXDefaultArguments(NewFD); 3969 } 3970} 3971 3972void Sema::CheckMain(FunctionDecl* FD) { 3973 // C++ [basic.start.main]p3: A program that declares main to be inline 3974 // or static is ill-formed. 3975 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3976 // shall not appear in a declaration of main. 3977 // static main is not an error under C99, but we should warn about it. 3978 bool isInline = FD->isInlineSpecified(); 3979 bool isStatic = FD->getStorageClass() == SC_Static; 3980 if (isInline || isStatic) { 3981 unsigned diagID = diag::warn_unusual_main_decl; 3982 if (isInline || getLangOptions().CPlusPlus) 3983 diagID = diag::err_unusual_main_decl; 3984 3985 int which = isStatic + (isInline << 1) - 1; 3986 Diag(FD->getLocation(), diagID) << which; 3987 } 3988 3989 QualType T = FD->getType(); 3990 assert(T->isFunctionType() && "function decl is not of function type"); 3991 const FunctionType* FT = T->getAs<FunctionType>(); 3992 3993 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3994 TypeSourceInfo *TSI = FD->getTypeSourceInfo(); 3995 TypeLoc TL = TSI->getTypeLoc(); 3996 const SemaDiagnosticBuilder& D = Diag(FD->getTypeSpecStartLoc(), 3997 diag::err_main_returns_nonint); 3998 if (FunctionTypeLoc* PTL = dyn_cast<FunctionTypeLoc>(&TL)) { 3999 D << FixItHint::CreateReplacement(PTL->getResultLoc().getSourceRange(), 4000 "int"); 4001 } 4002 FD->setInvalidDecl(true); 4003 } 4004 4005 // Treat protoless main() as nullary. 4006 if (isa<FunctionNoProtoType>(FT)) return; 4007 4008 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4009 unsigned nparams = FTP->getNumArgs(); 4010 assert(FD->getNumParams() == nparams); 4011 4012 bool HasExtraParameters = (nparams > 3); 4013 4014 // Darwin passes an undocumented fourth argument of type char**. If 4015 // other platforms start sprouting these, the logic below will start 4016 // getting shifty. 4017 if (nparams == 4 && 4018 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4019 HasExtraParameters = false; 4020 4021 if (HasExtraParameters) { 4022 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4023 FD->setInvalidDecl(true); 4024 nparams = 3; 4025 } 4026 4027 // FIXME: a lot of the following diagnostics would be improved 4028 // if we had some location information about types. 4029 4030 QualType CharPP = 4031 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4032 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4033 4034 for (unsigned i = 0; i < nparams; ++i) { 4035 QualType AT = FTP->getArgType(i); 4036 4037 bool mismatch = true; 4038 4039 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4040 mismatch = false; 4041 else if (Expected[i] == CharPP) { 4042 // As an extension, the following forms are okay: 4043 // char const ** 4044 // char const * const * 4045 // char * const * 4046 4047 QualifierCollector qs; 4048 const PointerType* PT; 4049 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4050 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4051 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4052 qs.removeConst(); 4053 mismatch = !qs.empty(); 4054 } 4055 } 4056 4057 if (mismatch) { 4058 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4059 // TODO: suggest replacing given type with expected type 4060 FD->setInvalidDecl(true); 4061 } 4062 } 4063 4064 if (nparams == 1 && !FD->isInvalidDecl()) { 4065 Diag(FD->getLocation(), diag::warn_main_one_arg); 4066 } 4067} 4068 4069bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4070 // FIXME: Need strict checking. In C89, we need to check for 4071 // any assignment, increment, decrement, function-calls, or 4072 // commas outside of a sizeof. In C99, it's the same list, 4073 // except that the aforementioned are allowed in unevaluated 4074 // expressions. Everything else falls under the 4075 // "may accept other forms of constant expressions" exception. 4076 // (We never end up here for C++, so the constant expression 4077 // rules there don't matter.) 4078 if (Init->isConstantInitializer(Context, false)) 4079 return false; 4080 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4081 << Init->getSourceRange(); 4082 return true; 4083} 4084 4085void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4086 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4087} 4088 4089/// AddInitializerToDecl - Adds the initializer Init to the 4090/// declaration dcl. If DirectInit is true, this is C++ direct 4091/// initialization rather than copy initialization. 4092void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4093 // If there is no declaration, there was an error parsing it. Just ignore 4094 // the initializer. 4095 if (RealDecl == 0) 4096 return; 4097 4098 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4099 // With declarators parsed the way they are, the parser cannot 4100 // distinguish between a normal initializer and a pure-specifier. 4101 // Thus this grotesque test. 4102 IntegerLiteral *IL; 4103 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4104 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4105 CheckPureMethod(Method, Init->getSourceRange()); 4106 else { 4107 Diag(Method->getLocation(), diag::err_member_function_initialization) 4108 << Method->getDeclName() << Init->getSourceRange(); 4109 Method->setInvalidDecl(); 4110 } 4111 return; 4112 } 4113 4114 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4115 if (!VDecl) { 4116 if (getLangOptions().CPlusPlus && 4117 RealDecl->getLexicalDeclContext()->isRecord() && 4118 isa<NamedDecl>(RealDecl)) 4119 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4120 else 4121 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4122 RealDecl->setInvalidDecl(); 4123 return; 4124 } 4125 4126 4127 4128 // A definition must end up with a complete type, which means it must be 4129 // complete with the restriction that an array type might be completed by the 4130 // initializer; note that later code assumes this restriction. 4131 QualType BaseDeclType = VDecl->getType(); 4132 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4133 BaseDeclType = Array->getElementType(); 4134 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4135 diag::err_typecheck_decl_incomplete_type)) { 4136 RealDecl->setInvalidDecl(); 4137 return; 4138 } 4139 4140 // The variable can not have an abstract class type. 4141 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4142 diag::err_abstract_type_in_decl, 4143 AbstractVariableType)) 4144 VDecl->setInvalidDecl(); 4145 4146 const VarDecl *Def; 4147 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4148 Diag(VDecl->getLocation(), diag::err_redefinition) 4149 << VDecl->getDeclName(); 4150 Diag(Def->getLocation(), diag::note_previous_definition); 4151 VDecl->setInvalidDecl(); 4152 return; 4153 } 4154 4155 // C++ [class.static.data]p4 4156 // If a static data member is of const integral or const 4157 // enumeration type, its declaration in the class definition can 4158 // specify a constant-initializer which shall be an integral 4159 // constant expression (5.19). In that case, the member can appear 4160 // in integral constant expressions. The member shall still be 4161 // defined in a namespace scope if it is used in the program and the 4162 // namespace scope definition shall not contain an initializer. 4163 // 4164 // We already performed a redefinition check above, but for static 4165 // data members we also need to check whether there was an in-class 4166 // declaration with an initializer. 4167 const VarDecl* PrevInit = 0; 4168 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4169 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4170 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4171 return; 4172 } 4173 4174 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4175 getCurFunction()->setHasBranchProtectedScope(); 4176 4177 // Capture the variable that is being initialized and the style of 4178 // initialization. 4179 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4180 4181 // FIXME: Poor source location information. 4182 InitializationKind Kind 4183 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4184 Init->getLocStart(), 4185 Init->getLocEnd()) 4186 : InitializationKind::CreateCopy(VDecl->getLocation(), 4187 Init->getLocStart()); 4188 4189 // Get the decls type and save a reference for later, since 4190 // CheckInitializerTypes may change it. 4191 QualType DclT = VDecl->getType(), SavT = DclT; 4192 if (VDecl->isBlockVarDecl()) { 4193 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4194 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4195 VDecl->setInvalidDecl(); 4196 } else if (!VDecl->isInvalidDecl()) { 4197 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4198 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4199 MultiExprArg(*this, &Init, 1), 4200 &DclT); 4201 if (Result.isInvalid()) { 4202 VDecl->setInvalidDecl(); 4203 return; 4204 } 4205 4206 Init = Result.takeAs<Expr>(); 4207 4208 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4209 // Don't check invalid declarations to avoid emitting useless diagnostics. 4210 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4211 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4212 CheckForConstantInitializer(Init, DclT); 4213 } 4214 } 4215 } else if (VDecl->isStaticDataMember() && 4216 VDecl->getLexicalDeclContext()->isRecord()) { 4217 // This is an in-class initialization for a static data member, e.g., 4218 // 4219 // struct S { 4220 // static const int value = 17; 4221 // }; 4222 4223 // Try to perform the initialization regardless. 4224 if (!VDecl->isInvalidDecl()) { 4225 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4226 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4227 MultiExprArg(*this, &Init, 1), 4228 &DclT); 4229 if (Result.isInvalid()) { 4230 VDecl->setInvalidDecl(); 4231 return; 4232 } 4233 4234 Init = Result.takeAs<Expr>(); 4235 } 4236 4237 // C++ [class.mem]p4: 4238 // A member-declarator can contain a constant-initializer only 4239 // if it declares a static member (9.4) of const integral or 4240 // const enumeration type, see 9.4.2. 4241 QualType T = VDecl->getType(); 4242 4243 // Do nothing on dependent types. 4244 if (T->isDependentType()) { 4245 4246 // Require constness. 4247 } else if (!T.isConstQualified()) { 4248 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4249 << Init->getSourceRange(); 4250 VDecl->setInvalidDecl(); 4251 4252 // We allow integer constant expressions in all cases. 4253 } else if (T->isIntegralOrEnumerationType()) { 4254 if (!Init->isValueDependent()) { 4255 // Check whether the expression is a constant expression. 4256 llvm::APSInt Value; 4257 SourceLocation Loc; 4258 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4259 Diag(Loc, diag::err_in_class_initializer_non_constant) 4260 << Init->getSourceRange(); 4261 VDecl->setInvalidDecl(); 4262 } 4263 } 4264 4265 // We allow floating-point constants as an extension in C++03, and 4266 // C++0x has far more complicated rules that we don't really 4267 // implement fully. 4268 } else { 4269 bool Allowed = false; 4270 if (getLangOptions().CPlusPlus0x) { 4271 Allowed = T->isLiteralType(); 4272 } else if (T->isFloatingType()) { // also permits complex, which is ok 4273 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4274 << T << Init->getSourceRange(); 4275 Allowed = true; 4276 } 4277 4278 if (!Allowed) { 4279 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4280 << T << Init->getSourceRange(); 4281 VDecl->setInvalidDecl(); 4282 4283 // TODO: there are probably expressions that pass here that shouldn't. 4284 } else if (!Init->isValueDependent() && 4285 !Init->isConstantInitializer(Context, false)) { 4286 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4287 << Init->getSourceRange(); 4288 VDecl->setInvalidDecl(); 4289 } 4290 } 4291 } else if (VDecl->isFileVarDecl()) { 4292 if (VDecl->getStorageClass() == SC_Extern && 4293 (!getLangOptions().CPlusPlus || 4294 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4295 Diag(VDecl->getLocation(), diag::warn_extern_init); 4296 if (!VDecl->isInvalidDecl()) { 4297 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4298 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4299 MultiExprArg(*this, &Init, 1), 4300 &DclT); 4301 if (Result.isInvalid()) { 4302 VDecl->setInvalidDecl(); 4303 return; 4304 } 4305 4306 Init = Result.takeAs<Expr>(); 4307 } 4308 4309 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4310 // Don't check invalid declarations to avoid emitting useless diagnostics. 4311 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4312 // C99 6.7.8p4. All file scoped initializers need to be constant. 4313 CheckForConstantInitializer(Init, DclT); 4314 } 4315 } 4316 // If the type changed, it means we had an incomplete type that was 4317 // completed by the initializer. For example: 4318 // int ary[] = { 1, 3, 5 }; 4319 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4320 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4321 VDecl->setType(DclT); 4322 Init->setType(DclT); 4323 } 4324 4325 Init = MaybeCreateCXXExprWithTemporaries(Init); 4326 // Attach the initializer to the decl. 4327 VDecl->setInit(Init); 4328 4329 if (getLangOptions().CPlusPlus) { 4330 if (!VDecl->isInvalidDecl() && 4331 !VDecl->getDeclContext()->isDependentContext() && 4332 VDecl->hasGlobalStorage() && !VDecl->isStaticLocal() && 4333 !Init->isConstantInitializer(Context, 4334 VDecl->getType()->isReferenceType())) 4335 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4336 << Init->getSourceRange(); 4337 4338 // Make sure we mark the destructor as used if necessary. 4339 QualType InitType = VDecl->getType(); 4340 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4341 InitType = Context.getBaseElementType(Array); 4342 if (const RecordType *Record = InitType->getAs<RecordType>()) 4343 FinalizeVarWithDestructor(VDecl, Record); 4344 } 4345 4346 return; 4347} 4348 4349/// ActOnInitializerError - Given that there was an error parsing an 4350/// initializer for the given declaration, try to return to some form 4351/// of sanity. 4352void Sema::ActOnInitializerError(Decl *D) { 4353 // Our main concern here is re-establishing invariants like "a 4354 // variable's type is either dependent or complete". 4355 if (!D || D->isInvalidDecl()) return; 4356 4357 VarDecl *VD = dyn_cast<VarDecl>(D); 4358 if (!VD) return; 4359 4360 QualType Ty = VD->getType(); 4361 if (Ty->isDependentType()) return; 4362 4363 // Require a complete type. 4364 if (RequireCompleteType(VD->getLocation(), 4365 Context.getBaseElementType(Ty), 4366 diag::err_typecheck_decl_incomplete_type)) { 4367 VD->setInvalidDecl(); 4368 return; 4369 } 4370 4371 // Require an abstract type. 4372 if (RequireNonAbstractType(VD->getLocation(), Ty, 4373 diag::err_abstract_type_in_decl, 4374 AbstractVariableType)) { 4375 VD->setInvalidDecl(); 4376 return; 4377 } 4378 4379 // Don't bother complaining about constructors or destructors, 4380 // though. 4381} 4382 4383void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4384 bool TypeContainsUndeducedAuto) { 4385 // If there is no declaration, there was an error parsing it. Just ignore it. 4386 if (RealDecl == 0) 4387 return; 4388 4389 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4390 QualType Type = Var->getType(); 4391 4392 // C++0x [dcl.spec.auto]p3 4393 if (TypeContainsUndeducedAuto) { 4394 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4395 << Var->getDeclName() << Type; 4396 Var->setInvalidDecl(); 4397 return; 4398 } 4399 4400 switch (Var->isThisDeclarationADefinition()) { 4401 case VarDecl::Definition: 4402 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4403 break; 4404 4405 // We have an out-of-line definition of a static data member 4406 // that has an in-class initializer, so we type-check this like 4407 // a declaration. 4408 // 4409 // Fall through 4410 4411 case VarDecl::DeclarationOnly: 4412 // It's only a declaration. 4413 4414 // Block scope. C99 6.7p7: If an identifier for an object is 4415 // declared with no linkage (C99 6.2.2p6), the type for the 4416 // object shall be complete. 4417 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4418 !Var->getLinkage() && !Var->isInvalidDecl() && 4419 RequireCompleteType(Var->getLocation(), Type, 4420 diag::err_typecheck_decl_incomplete_type)) 4421 Var->setInvalidDecl(); 4422 4423 // Make sure that the type is not abstract. 4424 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4425 RequireNonAbstractType(Var->getLocation(), Type, 4426 diag::err_abstract_type_in_decl, 4427 AbstractVariableType)) 4428 Var->setInvalidDecl(); 4429 return; 4430 4431 case VarDecl::TentativeDefinition: 4432 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4433 // object that has file scope without an initializer, and without a 4434 // storage-class specifier or with the storage-class specifier "static", 4435 // constitutes a tentative definition. Note: A tentative definition with 4436 // external linkage is valid (C99 6.2.2p5). 4437 if (!Var->isInvalidDecl()) { 4438 if (const IncompleteArrayType *ArrayT 4439 = Context.getAsIncompleteArrayType(Type)) { 4440 if (RequireCompleteType(Var->getLocation(), 4441 ArrayT->getElementType(), 4442 diag::err_illegal_decl_array_incomplete_type)) 4443 Var->setInvalidDecl(); 4444 } else if (Var->getStorageClass() == SC_Static) { 4445 // C99 6.9.2p3: If the declaration of an identifier for an object is 4446 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4447 // declared type shall not be an incomplete type. 4448 // NOTE: code such as the following 4449 // static struct s; 4450 // struct s { int a; }; 4451 // is accepted by gcc. Hence here we issue a warning instead of 4452 // an error and we do not invalidate the static declaration. 4453 // NOTE: to avoid multiple warnings, only check the first declaration. 4454 if (Var->getPreviousDeclaration() == 0) 4455 RequireCompleteType(Var->getLocation(), Type, 4456 diag::ext_typecheck_decl_incomplete_type); 4457 } 4458 } 4459 4460 // Record the tentative definition; we're done. 4461 if (!Var->isInvalidDecl()) 4462 TentativeDefinitions.push_back(Var); 4463 return; 4464 } 4465 4466 // Provide a specific diagnostic for uninitialized variable 4467 // definitions with incomplete array type. 4468 if (Type->isIncompleteArrayType()) { 4469 Diag(Var->getLocation(), 4470 diag::err_typecheck_incomplete_array_needs_initializer); 4471 Var->setInvalidDecl(); 4472 return; 4473 } 4474 4475 // Provide a specific diagnostic for uninitialized variable 4476 // definitions with reference type. 4477 if (Type->isReferenceType()) { 4478 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4479 << Var->getDeclName() 4480 << SourceRange(Var->getLocation(), Var->getLocation()); 4481 Var->setInvalidDecl(); 4482 return; 4483 } 4484 4485 // Do not attempt to type-check the default initializer for a 4486 // variable with dependent type. 4487 if (Type->isDependentType()) 4488 return; 4489 4490 if (Var->isInvalidDecl()) 4491 return; 4492 4493 if (RequireCompleteType(Var->getLocation(), 4494 Context.getBaseElementType(Type), 4495 diag::err_typecheck_decl_incomplete_type)) { 4496 Var->setInvalidDecl(); 4497 return; 4498 } 4499 4500 // The variable can not have an abstract class type. 4501 if (RequireNonAbstractType(Var->getLocation(), Type, 4502 diag::err_abstract_type_in_decl, 4503 AbstractVariableType)) { 4504 Var->setInvalidDecl(); 4505 return; 4506 } 4507 4508 const RecordType *Record 4509 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4510 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4511 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4512 // C++03 [dcl.init]p9: 4513 // If no initializer is specified for an object, and the 4514 // object is of (possibly cv-qualified) non-POD class type (or 4515 // array thereof), the object shall be default-initialized; if 4516 // the object is of const-qualified type, the underlying class 4517 // type shall have a user-declared default 4518 // constructor. Otherwise, if no initializer is specified for 4519 // a non- static object, the object and its subobjects, if 4520 // any, have an indeterminate initial value); if the object 4521 // or any of its subobjects are of const-qualified type, the 4522 // program is ill-formed. 4523 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4524 } else { 4525 // Check for jumps past the implicit initializer. C++0x 4526 // clarifies that this applies to a "variable with automatic 4527 // storage duration", not a "local variable". 4528 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4529 getCurFunction()->setHasBranchProtectedScope(); 4530 4531 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4532 InitializationKind Kind 4533 = InitializationKind::CreateDefault(Var->getLocation()); 4534 4535 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4536 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4537 MultiExprArg(*this, 0, 0)); 4538 if (Init.isInvalid()) 4539 Var->setInvalidDecl(); 4540 else if (Init.get()) { 4541 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4542 4543 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4544 Var->hasGlobalStorage() && !Var->isStaticLocal() && 4545 !Var->getDeclContext()->isDependentContext() && 4546 !Var->getInit()->isConstantInitializer(Context, false)) 4547 Diag(Var->getLocation(), diag::warn_global_constructor); 4548 } 4549 } 4550 4551 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4552 FinalizeVarWithDestructor(Var, Record); 4553 } 4554} 4555 4556Sema::DeclGroupPtrTy 4557Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4558 Decl **Group, unsigned NumDecls) { 4559 llvm::SmallVector<Decl*, 8> Decls; 4560 4561 if (DS.isTypeSpecOwned()) 4562 Decls.push_back(DS.getRepAsDecl()); 4563 4564 for (unsigned i = 0; i != NumDecls; ++i) 4565 if (Decl *D = Group[i]) 4566 Decls.push_back(D); 4567 4568 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4569 Decls.data(), Decls.size())); 4570} 4571 4572 4573/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4574/// to introduce parameters into function prototype scope. 4575Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4576 const DeclSpec &DS = D.getDeclSpec(); 4577 4578 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4579 VarDecl::StorageClass StorageClass = SC_None; 4580 VarDecl::StorageClass StorageClassAsWritten = SC_None; 4581 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4582 StorageClass = SC_Register; 4583 StorageClassAsWritten = SC_Register; 4584 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4585 Diag(DS.getStorageClassSpecLoc(), 4586 diag::err_invalid_storage_class_in_func_decl); 4587 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4588 } 4589 4590 if (D.getDeclSpec().isThreadSpecified()) 4591 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4592 4593 DiagnoseFunctionSpecifiers(D); 4594 4595 // Check that there are no default arguments inside the type of this 4596 // parameter (C++ only). 4597 if (getLangOptions().CPlusPlus) 4598 CheckExtraCXXDefaultArguments(D); 4599 4600 TagDecl *OwnedDecl = 0; 4601 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4602 QualType parmDeclType = TInfo->getType(); 4603 4604 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4605 // C++ [dcl.fct]p6: 4606 // Types shall not be defined in return or parameter types. 4607 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4608 << Context.getTypeDeclType(OwnedDecl); 4609 } 4610 4611 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4612 IdentifierInfo *II = D.getIdentifier(); 4613 if (II) { 4614 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4615 ForRedeclaration); 4616 LookupName(R, S); 4617 if (R.isSingleResult()) { 4618 NamedDecl *PrevDecl = R.getFoundDecl(); 4619 if (PrevDecl->isTemplateParameter()) { 4620 // Maybe we will complain about the shadowed template parameter. 4621 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4622 // Just pretend that we didn't see the previous declaration. 4623 PrevDecl = 0; 4624 } else if (S->isDeclScope(PrevDecl)) { 4625 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4626 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4627 4628 // Recover by removing the name 4629 II = 0; 4630 D.SetIdentifier(0, D.getIdentifierLoc()); 4631 D.setInvalidType(true); 4632 } 4633 } 4634 } 4635 4636 // Temporarily put parameter variables in the translation unit, not 4637 // the enclosing context. This prevents them from accidentally 4638 // looking like class members in C++. 4639 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4640 TInfo, parmDeclType, II, 4641 D.getIdentifierLoc(), 4642 StorageClass, StorageClassAsWritten); 4643 4644 if (D.isInvalidType()) 4645 New->setInvalidDecl(); 4646 4647 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4648 if (D.getCXXScopeSpec().isSet()) { 4649 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4650 << D.getCXXScopeSpec().getRange(); 4651 New->setInvalidDecl(); 4652 } 4653 4654 // Add the parameter declaration into this scope. 4655 S->AddDecl(New); 4656 if (II) 4657 IdResolver.AddDecl(New); 4658 4659 ProcessDeclAttributes(S, New, D); 4660 4661 if (New->hasAttr<BlocksAttr>()) { 4662 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4663 } 4664 return New; 4665} 4666 4667/// \brief Synthesizes a variable for a parameter arising from a 4668/// typedef. 4669ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4670 SourceLocation Loc, 4671 QualType T) { 4672 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4673 T, Context.getTrivialTypeSourceInfo(T, Loc), 4674 SC_None, SC_None, 0); 4675 Param->setImplicit(); 4676 return Param; 4677} 4678 4679void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 4680 ParmVarDecl * const *ParamEnd) { 4681 if (Diags.getDiagnosticLevel(diag::warn_unused_parameter) == 4682 Diagnostic::Ignored) 4683 return; 4684 4685 // Don't diagnose unused-parameter errors in template instantiations; we 4686 // will already have done so in the template itself. 4687 if (!ActiveTemplateInstantiations.empty()) 4688 return; 4689 4690 for (; Param != ParamEnd; ++Param) { 4691 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 4692 !(*Param)->hasAttr<UnusedAttr>()) { 4693 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 4694 << (*Param)->getDeclName(); 4695 } 4696 } 4697} 4698 4699ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4700 TypeSourceInfo *TSInfo, QualType T, 4701 IdentifierInfo *Name, 4702 SourceLocation NameLoc, 4703 VarDecl::StorageClass StorageClass, 4704 VarDecl::StorageClass StorageClassAsWritten) { 4705 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4706 adjustParameterType(T), TSInfo, 4707 StorageClass, StorageClassAsWritten, 4708 0); 4709 4710 // Parameters can not be abstract class types. 4711 // For record types, this is done by the AbstractClassUsageDiagnoser once 4712 // the class has been completely parsed. 4713 if (!CurContext->isRecord() && 4714 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4715 AbstractParamType)) 4716 New->setInvalidDecl(); 4717 4718 // Parameter declarators cannot be interface types. All ObjC objects are 4719 // passed by reference. 4720 if (T->isObjCObjectType()) { 4721 Diag(NameLoc, 4722 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4723 New->setInvalidDecl(); 4724 } 4725 4726 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4727 // duration shall not be qualified by an address-space qualifier." 4728 // Since all parameters have automatic store duration, they can not have 4729 // an address space. 4730 if (T.getAddressSpace() != 0) { 4731 Diag(NameLoc, diag::err_arg_with_address_space); 4732 New->setInvalidDecl(); 4733 } 4734 4735 return New; 4736} 4737 4738void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4739 SourceLocation LocAfterDecls) { 4740 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4741 "Not a function declarator!"); 4742 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4743 4744 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4745 // for a K&R function. 4746 if (!FTI.hasPrototype) { 4747 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4748 --i; 4749 if (FTI.ArgInfo[i].Param == 0) { 4750 llvm::SmallString<256> Code; 4751 llvm::raw_svector_ostream(Code) << " int " 4752 << FTI.ArgInfo[i].Ident->getName() 4753 << ";\n"; 4754 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4755 << FTI.ArgInfo[i].Ident 4756 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4757 4758 // Implicitly declare the argument as type 'int' for lack of a better 4759 // type. 4760 DeclSpec DS; 4761 const char* PrevSpec; // unused 4762 unsigned DiagID; // unused 4763 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4764 PrevSpec, DiagID); 4765 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4766 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4767 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4768 } 4769 } 4770 } 4771} 4772 4773Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4774 Declarator &D) { 4775 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4776 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4777 "Not a function declarator!"); 4778 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4779 4780 if (FTI.hasPrototype) { 4781 // FIXME: Diagnose arguments without names in C. 4782 } 4783 4784 Scope *ParentScope = FnBodyScope->getParent(); 4785 4786 Decl *DP = HandleDeclarator(ParentScope, D, 4787 MultiTemplateParamsArg(*this), 4788 /*IsFunctionDefinition=*/true); 4789 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4790} 4791 4792static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4793 // Don't warn about invalid declarations. 4794 if (FD->isInvalidDecl()) 4795 return false; 4796 4797 // Or declarations that aren't global. 4798 if (!FD->isGlobal()) 4799 return false; 4800 4801 // Don't warn about C++ member functions. 4802 if (isa<CXXMethodDecl>(FD)) 4803 return false; 4804 4805 // Don't warn about 'main'. 4806 if (FD->isMain()) 4807 return false; 4808 4809 // Don't warn about inline functions. 4810 if (FD->isInlineSpecified()) 4811 return false; 4812 4813 // Don't warn about function templates. 4814 if (FD->getDescribedFunctionTemplate()) 4815 return false; 4816 4817 // Don't warn about function template specializations. 4818 if (FD->isFunctionTemplateSpecialization()) 4819 return false; 4820 4821 bool MissingPrototype = true; 4822 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4823 Prev; Prev = Prev->getPreviousDeclaration()) { 4824 // Ignore any declarations that occur in function or method 4825 // scope, because they aren't visible from the header. 4826 if (Prev->getDeclContext()->isFunctionOrMethod()) 4827 continue; 4828 4829 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4830 break; 4831 } 4832 4833 return MissingPrototype; 4834} 4835 4836Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4837 // Clear the last template instantiation error context. 4838 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4839 4840 if (!D) 4841 return D; 4842 FunctionDecl *FD = 0; 4843 4844 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4845 FD = FunTmpl->getTemplatedDecl(); 4846 else 4847 FD = cast<FunctionDecl>(D); 4848 4849 // Enter a new function scope 4850 PushFunctionScope(); 4851 4852 // See if this is a redefinition. 4853 // But don't complain if we're in GNU89 mode and the previous definition 4854 // was an extern inline function. 4855 const FunctionDecl *Definition; 4856 if (FD->hasBody(Definition) && 4857 !canRedefineFunction(Definition, getLangOptions())) { 4858 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 4859 Definition->getStorageClass() == SC_Extern) 4860 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 4861 << FD->getDeclName() << getLangOptions().CPlusPlus; 4862 else 4863 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4864 Diag(Definition->getLocation(), diag::note_previous_definition); 4865 } 4866 4867 // Builtin functions cannot be defined. 4868 if (unsigned BuiltinID = FD->getBuiltinID()) { 4869 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4870 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4871 FD->setInvalidDecl(); 4872 } 4873 } 4874 4875 // The return type of a function definition must be complete 4876 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4877 QualType ResultType = FD->getResultType(); 4878 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4879 !FD->isInvalidDecl() && 4880 RequireCompleteType(FD->getLocation(), ResultType, 4881 diag::err_func_def_incomplete_result)) 4882 FD->setInvalidDecl(); 4883 4884 // GNU warning -Wmissing-prototypes: 4885 // Warn if a global function is defined without a previous 4886 // prototype declaration. This warning is issued even if the 4887 // definition itself provides a prototype. The aim is to detect 4888 // global functions that fail to be declared in header files. 4889 if (ShouldWarnAboutMissingPrototype(FD)) 4890 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4891 4892 if (FnBodyScope) 4893 PushDeclContext(FnBodyScope, FD); 4894 4895 // Check the validity of our function parameters 4896 CheckParmsForFunctionDef(FD); 4897 4898 bool ShouldCheckShadow = 4899 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4900 4901 // Introduce our parameters into the function scope 4902 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4903 ParmVarDecl *Param = FD->getParamDecl(p); 4904 Param->setOwningFunction(FD); 4905 4906 // If this has an identifier, add it to the scope stack. 4907 if (Param->getIdentifier() && FnBodyScope) { 4908 if (ShouldCheckShadow) 4909 CheckShadow(FnBodyScope, Param); 4910 4911 PushOnScopeChains(Param, FnBodyScope); 4912 } 4913 } 4914 4915 // Checking attributes of current function definition 4916 // dllimport attribute. 4917 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 4918 if (DA && (!FD->getAttr<DLLExportAttr>())) { 4919 // dllimport attribute cannot be directly applied to definition. 4920 if (!DA->isInherited()) { 4921 Diag(FD->getLocation(), 4922 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4923 << "dllimport"; 4924 FD->setInvalidDecl(); 4925 return FD; 4926 } 4927 4928 // Visual C++ appears to not think this is an issue, so only issue 4929 // a warning when Microsoft extensions are disabled. 4930 if (!LangOpts.Microsoft) { 4931 // If a symbol previously declared dllimport is later defined, the 4932 // attribute is ignored in subsequent references, and a warning is 4933 // emitted. 4934 Diag(FD->getLocation(), 4935 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4936 << FD->getName() << "dllimport"; 4937 } 4938 } 4939 return FD; 4940} 4941 4942/// \brief Given the set of return statements within a function body, 4943/// compute the variables that are subject to the named return value 4944/// optimization. 4945/// 4946/// Each of the variables that is subject to the named return value 4947/// optimization will be marked as NRVO variables in the AST, and any 4948/// return statement that has a marked NRVO variable as its NRVO candidate can 4949/// use the named return value optimization. 4950/// 4951/// This function applies a very simplistic algorithm for NRVO: if every return 4952/// statement in the function has the same NRVO candidate, that candidate is 4953/// the NRVO variable. 4954/// 4955/// FIXME: Employ a smarter algorithm that accounts for multiple return 4956/// statements and the lifetimes of the NRVO candidates. We should be able to 4957/// find a maximal set of NRVO variables. 4958static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 4959 ReturnStmt **Returns = Scope->Returns.data(); 4960 4961 const VarDecl *NRVOCandidate = 0; 4962 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 4963 if (!Returns[I]->getNRVOCandidate()) 4964 return; 4965 4966 if (!NRVOCandidate) 4967 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4968 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4969 return; 4970 } 4971 4972 if (NRVOCandidate) 4973 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4974} 4975 4976Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 4977 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4978} 4979 4980Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 4981 bool IsInstantiation) { 4982 FunctionDecl *FD = 0; 4983 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4984 if (FunTmpl) 4985 FD = FunTmpl->getTemplatedDecl(); 4986 else 4987 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4988 4989 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4990 4991 if (FD) { 4992 FD->setBody(Body); 4993 if (FD->isMain()) { 4994 // C and C++ allow for main to automagically return 0. 4995 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4996 FD->setHasImplicitReturnZero(true); 4997 WP.disableCheckFallThrough(); 4998 } 4999 5000 if (!FD->isInvalidDecl()) { 5001 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5002 5003 // If this is a constructor, we need a vtable. 5004 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5005 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5006 5007 ComputeNRVO(Body, getCurFunction()); 5008 } 5009 5010 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5011 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5012 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5013 MD->setBody(Body); 5014 MD->setEndLoc(Body->getLocEnd()); 5015 if (!MD->isInvalidDecl()) 5016 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5017 } else { 5018 return 0; 5019 } 5020 5021 // Verify and clean out per-function state. 5022 5023 // Check goto/label use. 5024 FunctionScopeInfo *CurFn = getCurFunction(); 5025 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 5026 I = CurFn->LabelMap.begin(), E = CurFn->LabelMap.end(); I != E; ++I) { 5027 LabelStmt *L = I->second; 5028 5029 // Verify that we have no forward references left. If so, there was a goto 5030 // or address of a label taken, but no definition of it. Label fwd 5031 // definitions are indicated with a null substmt. 5032 if (L->getSubStmt() != 0) { 5033 if (!L->isUsed()) 5034 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 5035 continue; 5036 } 5037 5038 // Emit error. 5039 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 5040 5041 // At this point, we have gotos that use the bogus label. Stitch it into 5042 // the function body so that they aren't leaked and that the AST is well 5043 // formed. 5044 if (Body == 0) { 5045 // The whole function wasn't parsed correctly. 5046 continue; 5047 } 5048 5049 // Otherwise, the body is valid: we want to stitch the label decl into the 5050 // function somewhere so that it is properly owned and so that the goto 5051 // has a valid target. Do this by creating a new compound stmt with the 5052 // label in it. 5053 5054 // Give the label a sub-statement. 5055 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 5056 5057 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 5058 cast<CXXTryStmt>(Body)->getTryBlock() : 5059 cast<CompoundStmt>(Body); 5060 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 5061 Compound->body_end()); 5062 Elements.push_back(L); 5063 Compound->setStmts(Context, Elements.data(), Elements.size()); 5064 } 5065 5066 if (Body) { 5067 // C++ constructors that have function-try-blocks can't have return 5068 // statements in the handlers of that block. (C++ [except.handle]p14) 5069 // Verify this. 5070 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5071 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5072 5073 // Verify that that gotos and switch cases don't jump into scopes illegally. 5074 // Verify that that gotos and switch cases don't jump into scopes illegally. 5075 if (getCurFunction()->NeedsScopeChecking() && 5076 !dcl->isInvalidDecl() && 5077 !hasAnyErrorsInThisFunction()) 5078 DiagnoseInvalidJumps(Body); 5079 5080 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5081 if (!Destructor->getParent()->isDependentType()) 5082 CheckDestructor(Destructor); 5083 5084 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5085 Destructor->getParent()); 5086 } 5087 5088 // If any errors have occurred, clear out any temporaries that may have 5089 // been leftover. This ensures that these temporaries won't be picked up for 5090 // deletion in some later function. 5091 if (PP.getDiagnostics().hasErrorOccurred()) 5092 ExprTemporaries.clear(); 5093 else if (!isa<FunctionTemplateDecl>(dcl)) { 5094 // Since the body is valid, issue any analysis-based warnings that are 5095 // enabled. 5096 QualType ResultType; 5097 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 5098 AnalysisWarnings.IssueWarnings(WP, FD); 5099 } else { 5100 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 5101 AnalysisWarnings.IssueWarnings(WP, MD); 5102 } 5103 } 5104 5105 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5106 } 5107 5108 if (!IsInstantiation) 5109 PopDeclContext(); 5110 5111 PopFunctionOrBlockScope(); 5112 5113 // If any errors have occurred, clear out any temporaries that may have 5114 // been leftover. This ensures that these temporaries won't be picked up for 5115 // deletion in some later function. 5116 if (getDiagnostics().hasErrorOccurred()) 5117 ExprTemporaries.clear(); 5118 5119 return dcl; 5120} 5121 5122/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5123/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5124NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5125 IdentifierInfo &II, Scope *S) { 5126 // Before we produce a declaration for an implicitly defined 5127 // function, see whether there was a locally-scoped declaration of 5128 // this name as a function or variable. If so, use that 5129 // (non-visible) declaration, and complain about it. 5130 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5131 = LocallyScopedExternalDecls.find(&II); 5132 if (Pos != LocallyScopedExternalDecls.end()) { 5133 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5134 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5135 return Pos->second; 5136 } 5137 5138 // Extension in C99. Legal in C90, but warn about it. 5139 if (II.getName().startswith("__builtin_")) 5140 Diag(Loc, diag::warn_builtin_unknown) << &II; 5141 else if (getLangOptions().C99) 5142 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5143 else 5144 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5145 5146 // Set a Declarator for the implicit definition: int foo(); 5147 const char *Dummy; 5148 DeclSpec DS; 5149 unsigned DiagID; 5150 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5151 Error = Error; // Silence warning. 5152 assert(!Error && "Error setting up implicit decl!"); 5153 Declarator D(DS, Declarator::BlockContext); 5154 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5155 0, 0, false, SourceLocation(), 5156 false, 0,0,0, Loc, Loc, D), 5157 SourceLocation()); 5158 D.SetIdentifier(&II, Loc); 5159 5160 // Insert this function into translation-unit scope. 5161 5162 DeclContext *PrevDC = CurContext; 5163 CurContext = Context.getTranslationUnitDecl(); 5164 5165 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5166 FD->setImplicit(); 5167 5168 CurContext = PrevDC; 5169 5170 AddKnownFunctionAttributes(FD); 5171 5172 return FD; 5173} 5174 5175/// \brief Adds any function attributes that we know a priori based on 5176/// the declaration of this function. 5177/// 5178/// These attributes can apply both to implicitly-declared builtins 5179/// (like __builtin___printf_chk) or to library-declared functions 5180/// like NSLog or printf. 5181void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5182 if (FD->isInvalidDecl()) 5183 return; 5184 5185 // If this is a built-in function, map its builtin attributes to 5186 // actual attributes. 5187 if (unsigned BuiltinID = FD->getBuiltinID()) { 5188 // Handle printf-formatting attributes. 5189 unsigned FormatIdx; 5190 bool HasVAListArg; 5191 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5192 if (!FD->getAttr<FormatAttr>()) 5193 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5194 "printf", FormatIdx+1, 5195 HasVAListArg ? 0 : FormatIdx+2)); 5196 } 5197 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5198 HasVAListArg)) { 5199 if (!FD->getAttr<FormatAttr>()) 5200 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5201 "scanf", FormatIdx+1, 5202 HasVAListArg ? 0 : FormatIdx+2)); 5203 } 5204 5205 // Mark const if we don't care about errno and that is the only 5206 // thing preventing the function from being const. This allows 5207 // IRgen to use LLVM intrinsics for such functions. 5208 if (!getLangOptions().MathErrno && 5209 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5210 if (!FD->getAttr<ConstAttr>()) 5211 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5212 } 5213 5214 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5215 FD->setType(Context.getNoReturnType(FD->getType())); 5216 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5217 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5218 if (Context.BuiltinInfo.isConst(BuiltinID)) 5219 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5220 } 5221 5222 IdentifierInfo *Name = FD->getIdentifier(); 5223 if (!Name) 5224 return; 5225 if ((!getLangOptions().CPlusPlus && 5226 FD->getDeclContext()->isTranslationUnit()) || 5227 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5228 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5229 LinkageSpecDecl::lang_c)) { 5230 // Okay: this could be a libc/libm/Objective-C function we know 5231 // about. 5232 } else 5233 return; 5234 5235 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5236 // FIXME: NSLog and NSLogv should be target specific 5237 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5238 // FIXME: We known better than our headers. 5239 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5240 } else 5241 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5242 "printf", 1, 5243 Name->isStr("NSLogv") ? 0 : 2)); 5244 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5245 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5246 // target-specific builtins, perhaps? 5247 if (!FD->getAttr<FormatAttr>()) 5248 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5249 "printf", 2, 5250 Name->isStr("vasprintf") ? 0 : 3)); 5251 } 5252} 5253 5254TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5255 TypeSourceInfo *TInfo) { 5256 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5257 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5258 5259 if (!TInfo) { 5260 assert(D.isInvalidType() && "no declarator info for valid type"); 5261 TInfo = Context.getTrivialTypeSourceInfo(T); 5262 } 5263 5264 // Scope manipulation handled by caller. 5265 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5266 D.getIdentifierLoc(), 5267 D.getIdentifier(), 5268 TInfo); 5269 5270 if (const TagType *TT = T->getAs<TagType>()) { 5271 TagDecl *TD = TT->getDecl(); 5272 5273 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5274 // keep track of the TypedefDecl. 5275 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5276 TD->setTypedefForAnonDecl(NewTD); 5277 } 5278 5279 if (D.isInvalidType()) 5280 NewTD->setInvalidDecl(); 5281 return NewTD; 5282} 5283 5284 5285/// \brief Determine whether a tag with a given kind is acceptable 5286/// as a redeclaration of the given tag declaration. 5287/// 5288/// \returns true if the new tag kind is acceptable, false otherwise. 5289bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5290 TagTypeKind NewTag, 5291 SourceLocation NewTagLoc, 5292 const IdentifierInfo &Name) { 5293 // C++ [dcl.type.elab]p3: 5294 // The class-key or enum keyword present in the 5295 // elaborated-type-specifier shall agree in kind with the 5296 // declaration to which the name in the elaborated-type-specifier 5297 // refers. This rule also applies to the form of 5298 // elaborated-type-specifier that declares a class-name or 5299 // friend class since it can be construed as referring to the 5300 // definition of the class. Thus, in any 5301 // elaborated-type-specifier, the enum keyword shall be used to 5302 // refer to an enumeration (7.2), the union class-key shall be 5303 // used to refer to a union (clause 9), and either the class or 5304 // struct class-key shall be used to refer to a class (clause 9) 5305 // declared using the class or struct class-key. 5306 TagTypeKind OldTag = Previous->getTagKind(); 5307 if (OldTag == NewTag) 5308 return true; 5309 5310 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5311 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5312 // Warn about the struct/class tag mismatch. 5313 bool isTemplate = false; 5314 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5315 isTemplate = Record->getDescribedClassTemplate(); 5316 5317 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5318 << (NewTag == TTK_Class) 5319 << isTemplate << &Name 5320 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5321 OldTag == TTK_Class? "class" : "struct"); 5322 Diag(Previous->getLocation(), diag::note_previous_use); 5323 return true; 5324 } 5325 return false; 5326} 5327 5328/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5329/// former case, Name will be non-null. In the later case, Name will be null. 5330/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5331/// reference/declaration/definition of a tag. 5332Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5333 SourceLocation KWLoc, CXXScopeSpec &SS, 5334 IdentifierInfo *Name, SourceLocation NameLoc, 5335 AttributeList *Attr, AccessSpecifier AS, 5336 MultiTemplateParamsArg TemplateParameterLists, 5337 bool &OwnedDecl, bool &IsDependent) { 5338 // If this is not a definition, it must have a name. 5339 assert((Name != 0 || TUK == TUK_Definition) && 5340 "Nameless record must be a definition!"); 5341 5342 OwnedDecl = false; 5343 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5344 5345 // FIXME: Check explicit specializations more carefully. 5346 bool isExplicitSpecialization = false; 5347 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5348 bool Invalid = false; 5349 if (TUK != TUK_Reference) { 5350 if (TemplateParameterList *TemplateParams 5351 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5352 (TemplateParameterList**)TemplateParameterLists.get(), 5353 TemplateParameterLists.size(), 5354 TUK == TUK_Friend, 5355 isExplicitSpecialization, 5356 Invalid)) { 5357 // All but one template parameter lists have been matching. 5358 --NumMatchedTemplateParamLists; 5359 5360 if (TemplateParams->size() > 0) { 5361 // This is a declaration or definition of a class template (which may 5362 // be a member of another template). 5363 if (Invalid) 5364 return 0; 5365 5366 OwnedDecl = false; 5367 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5368 SS, Name, NameLoc, Attr, 5369 TemplateParams, 5370 AS); 5371 TemplateParameterLists.release(); 5372 return Result.get(); 5373 } else { 5374 // The "template<>" header is extraneous. 5375 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5376 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5377 isExplicitSpecialization = true; 5378 } 5379 } 5380 } 5381 5382 DeclContext *SearchDC = CurContext; 5383 DeclContext *DC = CurContext; 5384 bool isStdBadAlloc = false; 5385 5386 RedeclarationKind Redecl = ForRedeclaration; 5387 if (TUK == TUK_Friend || TUK == TUK_Reference) 5388 Redecl = NotForRedeclaration; 5389 5390 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5391 5392 if (Name && SS.isNotEmpty()) { 5393 // We have a nested-name tag ('struct foo::bar'). 5394 5395 // Check for invalid 'foo::'. 5396 if (SS.isInvalid()) { 5397 Name = 0; 5398 goto CreateNewDecl; 5399 } 5400 5401 // If this is a friend or a reference to a class in a dependent 5402 // context, don't try to make a decl for it. 5403 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5404 DC = computeDeclContext(SS, false); 5405 if (!DC) { 5406 IsDependent = true; 5407 return 0; 5408 } 5409 } else { 5410 DC = computeDeclContext(SS, true); 5411 if (!DC) { 5412 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5413 << SS.getRange(); 5414 return 0; 5415 } 5416 } 5417 5418 if (RequireCompleteDeclContext(SS, DC)) 5419 return 0; 5420 5421 SearchDC = DC; 5422 // Look-up name inside 'foo::'. 5423 LookupQualifiedName(Previous, DC); 5424 5425 if (Previous.isAmbiguous()) 5426 return 0; 5427 5428 if (Previous.empty()) { 5429 // Name lookup did not find anything. However, if the 5430 // nested-name-specifier refers to the current instantiation, 5431 // and that current instantiation has any dependent base 5432 // classes, we might find something at instantiation time: treat 5433 // this as a dependent elaborated-type-specifier. 5434 if (Previous.wasNotFoundInCurrentInstantiation()) { 5435 IsDependent = true; 5436 return 0; 5437 } 5438 5439 // A tag 'foo::bar' must already exist. 5440 Diag(NameLoc, diag::err_not_tag_in_scope) 5441 << Kind << Name << DC << SS.getRange(); 5442 Name = 0; 5443 Invalid = true; 5444 goto CreateNewDecl; 5445 } 5446 } else if (Name) { 5447 // If this is a named struct, check to see if there was a previous forward 5448 // declaration or definition. 5449 // FIXME: We're looking into outer scopes here, even when we 5450 // shouldn't be. Doing so can result in ambiguities that we 5451 // shouldn't be diagnosing. 5452 LookupName(Previous, S); 5453 5454 // Note: there used to be some attempt at recovery here. 5455 if (Previous.isAmbiguous()) 5456 return 0; 5457 5458 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5459 // FIXME: This makes sure that we ignore the contexts associated 5460 // with C structs, unions, and enums when looking for a matching 5461 // tag declaration or definition. See the similar lookup tweak 5462 // in Sema::LookupName; is there a better way to deal with this? 5463 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5464 SearchDC = SearchDC->getParent(); 5465 } 5466 } else if (S->isFunctionPrototypeScope()) { 5467 // If this is an enum declaration in function prototype scope, set its 5468 // initial context to the translation unit. 5469 SearchDC = Context.getTranslationUnitDecl(); 5470 } 5471 5472 if (Previous.isSingleResult() && 5473 Previous.getFoundDecl()->isTemplateParameter()) { 5474 // Maybe we will complain about the shadowed template parameter. 5475 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5476 // Just pretend that we didn't see the previous declaration. 5477 Previous.clear(); 5478 } 5479 5480 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5481 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5482 // This is a declaration of or a reference to "std::bad_alloc". 5483 isStdBadAlloc = true; 5484 5485 if (Previous.empty() && StdBadAlloc) { 5486 // std::bad_alloc has been implicitly declared (but made invisible to 5487 // name lookup). Fill in this implicit declaration as the previous 5488 // declaration, so that the declarations get chained appropriately. 5489 Previous.addDecl(getStdBadAlloc()); 5490 } 5491 } 5492 5493 // If we didn't find a previous declaration, and this is a reference 5494 // (or friend reference), move to the correct scope. In C++, we 5495 // also need to do a redeclaration lookup there, just in case 5496 // there's a shadow friend decl. 5497 if (Name && Previous.empty() && 5498 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5499 if (Invalid) goto CreateNewDecl; 5500 assert(SS.isEmpty()); 5501 5502 if (TUK == TUK_Reference) { 5503 // C++ [basic.scope.pdecl]p5: 5504 // -- for an elaborated-type-specifier of the form 5505 // 5506 // class-key identifier 5507 // 5508 // if the elaborated-type-specifier is used in the 5509 // decl-specifier-seq or parameter-declaration-clause of a 5510 // function defined in namespace scope, the identifier is 5511 // declared as a class-name in the namespace that contains 5512 // the declaration; otherwise, except as a friend 5513 // declaration, the identifier is declared in the smallest 5514 // non-class, non-function-prototype scope that contains the 5515 // declaration. 5516 // 5517 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5518 // C structs and unions. 5519 // 5520 // It is an error in C++ to declare (rather than define) an enum 5521 // type, including via an elaborated type specifier. We'll 5522 // diagnose that later; for now, declare the enum in the same 5523 // scope as we would have picked for any other tag type. 5524 // 5525 // GNU C also supports this behavior as part of its incomplete 5526 // enum types extension, while GNU C++ does not. 5527 // 5528 // Find the context where we'll be declaring the tag. 5529 // FIXME: We would like to maintain the current DeclContext as the 5530 // lexical context, 5531 while (SearchDC->isRecord()) 5532 SearchDC = SearchDC->getParent(); 5533 5534 // Find the scope where we'll be declaring the tag. 5535 while (S->isClassScope() || 5536 (getLangOptions().CPlusPlus && 5537 S->isFunctionPrototypeScope()) || 5538 ((S->getFlags() & Scope::DeclScope) == 0) || 5539 (S->getEntity() && 5540 ((DeclContext *)S->getEntity())->isTransparentContext())) 5541 S = S->getParent(); 5542 } else { 5543 assert(TUK == TUK_Friend); 5544 // C++ [namespace.memdef]p3: 5545 // If a friend declaration in a non-local class first declares a 5546 // class or function, the friend class or function is a member of 5547 // the innermost enclosing namespace. 5548 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5549 } 5550 5551 // In C++, we need to do a redeclaration lookup to properly 5552 // diagnose some problems. 5553 if (getLangOptions().CPlusPlus) { 5554 Previous.setRedeclarationKind(ForRedeclaration); 5555 LookupQualifiedName(Previous, SearchDC); 5556 } 5557 } 5558 5559 if (!Previous.empty()) { 5560 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5561 5562 // It's okay to have a tag decl in the same scope as a typedef 5563 // which hides a tag decl in the same scope. Finding this 5564 // insanity with a redeclaration lookup can only actually happen 5565 // in C++. 5566 // 5567 // This is also okay for elaborated-type-specifiers, which is 5568 // technically forbidden by the current standard but which is 5569 // okay according to the likely resolution of an open issue; 5570 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5571 if (getLangOptions().CPlusPlus) { 5572 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5573 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5574 TagDecl *Tag = TT->getDecl(); 5575 if (Tag->getDeclName() == Name && 5576 Tag->getDeclContext()->getRedeclContext() 5577 ->Equals(TD->getDeclContext()->getRedeclContext())) { 5578 PrevDecl = Tag; 5579 Previous.clear(); 5580 Previous.addDecl(Tag); 5581 Previous.resolveKind(); 5582 } 5583 } 5584 } 5585 } 5586 5587 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5588 // If this is a use of a previous tag, or if the tag is already declared 5589 // in the same scope (so that the definition/declaration completes or 5590 // rementions the tag), reuse the decl. 5591 if (TUK == TUK_Reference || TUK == TUK_Friend || 5592 isDeclInScope(PrevDecl, SearchDC, S)) { 5593 // Make sure that this wasn't declared as an enum and now used as a 5594 // struct or something similar. 5595 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5596 bool SafeToContinue 5597 = (PrevTagDecl->getTagKind() != TTK_Enum && 5598 Kind != TTK_Enum); 5599 if (SafeToContinue) 5600 Diag(KWLoc, diag::err_use_with_wrong_tag) 5601 << Name 5602 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5603 PrevTagDecl->getKindName()); 5604 else 5605 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5606 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5607 5608 if (SafeToContinue) 5609 Kind = PrevTagDecl->getTagKind(); 5610 else { 5611 // Recover by making this an anonymous redefinition. 5612 Name = 0; 5613 Previous.clear(); 5614 Invalid = true; 5615 } 5616 } 5617 5618 if (!Invalid) { 5619 // If this is a use, just return the declaration we found. 5620 5621 // FIXME: In the future, return a variant or some other clue 5622 // for the consumer of this Decl to know it doesn't own it. 5623 // For our current ASTs this shouldn't be a problem, but will 5624 // need to be changed with DeclGroups. 5625 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5626 TUK == TUK_Friend) 5627 return PrevTagDecl; 5628 5629 // Diagnose attempts to redefine a tag. 5630 if (TUK == TUK_Definition) { 5631 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5632 // If we're defining a specialization and the previous definition 5633 // is from an implicit instantiation, don't emit an error 5634 // here; we'll catch this in the general case below. 5635 if (!isExplicitSpecialization || 5636 !isa<CXXRecordDecl>(Def) || 5637 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5638 == TSK_ExplicitSpecialization) { 5639 Diag(NameLoc, diag::err_redefinition) << Name; 5640 Diag(Def->getLocation(), diag::note_previous_definition); 5641 // If this is a redefinition, recover by making this 5642 // struct be anonymous, which will make any later 5643 // references get the previous definition. 5644 Name = 0; 5645 Previous.clear(); 5646 Invalid = true; 5647 } 5648 } else { 5649 // If the type is currently being defined, complain 5650 // about a nested redefinition. 5651 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5652 if (Tag->isBeingDefined()) { 5653 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5654 Diag(PrevTagDecl->getLocation(), 5655 diag::note_previous_definition); 5656 Name = 0; 5657 Previous.clear(); 5658 Invalid = true; 5659 } 5660 } 5661 5662 // Okay, this is definition of a previously declared or referenced 5663 // tag PrevDecl. We're going to create a new Decl for it. 5664 } 5665 } 5666 // If we get here we have (another) forward declaration or we 5667 // have a definition. Just create a new decl. 5668 5669 } else { 5670 // If we get here, this is a definition of a new tag type in a nested 5671 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5672 // new decl/type. We set PrevDecl to NULL so that the entities 5673 // have distinct types. 5674 Previous.clear(); 5675 } 5676 // If we get here, we're going to create a new Decl. If PrevDecl 5677 // is non-NULL, it's a definition of the tag declared by 5678 // PrevDecl. If it's NULL, we have a new definition. 5679 5680 5681 // Otherwise, PrevDecl is not a tag, but was found with tag 5682 // lookup. This is only actually possible in C++, where a few 5683 // things like templates still live in the tag namespace. 5684 } else { 5685 assert(getLangOptions().CPlusPlus); 5686 5687 // Use a better diagnostic if an elaborated-type-specifier 5688 // found the wrong kind of type on the first 5689 // (non-redeclaration) lookup. 5690 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5691 !Previous.isForRedeclaration()) { 5692 unsigned Kind = 0; 5693 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5694 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5695 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5696 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5697 Invalid = true; 5698 5699 // Otherwise, only diagnose if the declaration is in scope. 5700 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5701 // do nothing 5702 5703 // Diagnose implicit declarations introduced by elaborated types. 5704 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5705 unsigned Kind = 0; 5706 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5707 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5708 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5709 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5710 Invalid = true; 5711 5712 // Otherwise it's a declaration. Call out a particularly common 5713 // case here. 5714 } else if (isa<TypedefDecl>(PrevDecl)) { 5715 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5716 << Name 5717 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5718 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5719 Invalid = true; 5720 5721 // Otherwise, diagnose. 5722 } else { 5723 // The tag name clashes with something else in the target scope, 5724 // issue an error and recover by making this tag be anonymous. 5725 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5726 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5727 Name = 0; 5728 Invalid = true; 5729 } 5730 5731 // The existing declaration isn't relevant to us; we're in a 5732 // new scope, so clear out the previous declaration. 5733 Previous.clear(); 5734 } 5735 } 5736 5737CreateNewDecl: 5738 5739 TagDecl *PrevDecl = 0; 5740 if (Previous.isSingleResult()) 5741 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5742 5743 // If there is an identifier, use the location of the identifier as the 5744 // location of the decl, otherwise use the location of the struct/union 5745 // keyword. 5746 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5747 5748 // Otherwise, create a new declaration. If there is a previous 5749 // declaration of the same entity, the two will be linked via 5750 // PrevDecl. 5751 TagDecl *New; 5752 5753 if (Kind == TTK_Enum) { 5754 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5755 // enum X { A, B, C } D; D should chain to X. 5756 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5757 cast_or_null<EnumDecl>(PrevDecl)); 5758 // If this is an undefined enum, warn. 5759 if (TUK != TUK_Definition && !Invalid) { 5760 TagDecl *Def; 5761 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5762 Diag(Loc, diag::ext_forward_ref_enum_def) 5763 << New; 5764 Diag(Def->getLocation(), diag::note_previous_definition); 5765 } else { 5766 unsigned DiagID = diag::ext_forward_ref_enum; 5767 if (getLangOptions().Microsoft) 5768 DiagID = diag::ext_ms_forward_ref_enum; 5769 else if (getLangOptions().CPlusPlus) 5770 DiagID = diag::err_forward_ref_enum; 5771 Diag(Loc, DiagID); 5772 } 5773 } 5774 } else { 5775 // struct/union/class 5776 5777 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5778 // struct X { int A; } D; D should chain to X. 5779 if (getLangOptions().CPlusPlus) { 5780 // FIXME: Look for a way to use RecordDecl for simple structs. 5781 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5782 cast_or_null<CXXRecordDecl>(PrevDecl)); 5783 5784 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5785 StdBadAlloc = cast<CXXRecordDecl>(New); 5786 } else 5787 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5788 cast_or_null<RecordDecl>(PrevDecl)); 5789 } 5790 5791 // Maybe add qualifier info. 5792 if (SS.isNotEmpty()) { 5793 if (SS.isSet()) { 5794 NestedNameSpecifier *NNS 5795 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5796 New->setQualifierInfo(NNS, SS.getRange()); 5797 if (NumMatchedTemplateParamLists > 0) { 5798 New->setTemplateParameterListsInfo(Context, 5799 NumMatchedTemplateParamLists, 5800 (TemplateParameterList**) TemplateParameterLists.release()); 5801 } 5802 } 5803 else 5804 Invalid = true; 5805 } 5806 5807 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5808 // Add alignment attributes if necessary; these attributes are checked when 5809 // the ASTContext lays out the structure. 5810 // 5811 // It is important for implementing the correct semantics that this 5812 // happen here (in act on tag decl). The #pragma pack stack is 5813 // maintained as a result of parser callbacks which can occur at 5814 // many points during the parsing of a struct declaration (because 5815 // the #pragma tokens are effectively skipped over during the 5816 // parsing of the struct). 5817 AddAlignmentAttributesForRecord(RD); 5818 } 5819 5820 // If this is a specialization of a member class (of a class template), 5821 // check the specialization. 5822 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5823 Invalid = true; 5824 5825 if (Invalid) 5826 New->setInvalidDecl(); 5827 5828 if (Attr) 5829 ProcessDeclAttributeList(S, New, Attr); 5830 5831 // If we're declaring or defining a tag in function prototype scope 5832 // in C, note that this type can only be used within the function. 5833 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5834 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5835 5836 // Set the lexical context. If the tag has a C++ scope specifier, the 5837 // lexical context will be different from the semantic context. 5838 New->setLexicalDeclContext(CurContext); 5839 5840 // Mark this as a friend decl if applicable. 5841 if (TUK == TUK_Friend) 5842 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5843 5844 // Set the access specifier. 5845 if (!Invalid && SearchDC->isRecord()) 5846 SetMemberAccessSpecifier(New, PrevDecl, AS); 5847 5848 if (TUK == TUK_Definition) 5849 New->startDefinition(); 5850 5851 // If this has an identifier, add it to the scope stack. 5852 if (TUK == TUK_Friend) { 5853 // We might be replacing an existing declaration in the lookup tables; 5854 // if so, borrow its access specifier. 5855 if (PrevDecl) 5856 New->setAccess(PrevDecl->getAccess()); 5857 5858 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 5859 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5860 if (Name) // can be null along some error paths 5861 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5862 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5863 } else if (Name) { 5864 S = getNonFieldDeclScope(S); 5865 PushOnScopeChains(New, S); 5866 } else { 5867 CurContext->addDecl(New); 5868 } 5869 5870 // If this is the C FILE type, notify the AST context. 5871 if (IdentifierInfo *II = New->getIdentifier()) 5872 if (!New->isInvalidDecl() && 5873 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 5874 II->isStr("FILE")) 5875 Context.setFILEDecl(New); 5876 5877 OwnedDecl = true; 5878 return New; 5879} 5880 5881void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 5882 AdjustDeclIfTemplate(TagD); 5883 TagDecl *Tag = cast<TagDecl>(TagD); 5884 5885 // Enter the tag context. 5886 PushDeclContext(S, Tag); 5887} 5888 5889void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 5890 SourceLocation LBraceLoc) { 5891 AdjustDeclIfTemplate(TagD); 5892 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 5893 5894 FieldCollector->StartClass(); 5895 5896 if (!Record->getIdentifier()) 5897 return; 5898 5899 // C++ [class]p2: 5900 // [...] The class-name is also inserted into the scope of the 5901 // class itself; this is known as the injected-class-name. For 5902 // purposes of access checking, the injected-class-name is treated 5903 // as if it were a public member name. 5904 CXXRecordDecl *InjectedClassName 5905 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5906 CurContext, Record->getLocation(), 5907 Record->getIdentifier(), 5908 Record->getTagKeywordLoc(), 5909 Record); 5910 InjectedClassName->setImplicit(); 5911 InjectedClassName->setAccess(AS_public); 5912 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5913 InjectedClassName->setDescribedClassTemplate(Template); 5914 PushOnScopeChains(InjectedClassName, S); 5915 assert(InjectedClassName->isInjectedClassName() && 5916 "Broken injected-class-name"); 5917} 5918 5919void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 5920 SourceLocation RBraceLoc) { 5921 AdjustDeclIfTemplate(TagD); 5922 TagDecl *Tag = cast<TagDecl>(TagD); 5923 Tag->setRBraceLoc(RBraceLoc); 5924 5925 if (isa<CXXRecordDecl>(Tag)) 5926 FieldCollector->FinishClass(); 5927 5928 // Exit this scope of this tag's definition. 5929 PopDeclContext(); 5930 5931 // Notify the consumer that we've defined a tag. 5932 Consumer.HandleTagDeclDefinition(Tag); 5933} 5934 5935void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 5936 AdjustDeclIfTemplate(TagD); 5937 TagDecl *Tag = cast<TagDecl>(TagD); 5938 Tag->setInvalidDecl(); 5939 5940 // We're undoing ActOnTagStartDefinition here, not 5941 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5942 // the FieldCollector. 5943 5944 PopDeclContext(); 5945} 5946 5947// Note that FieldName may be null for anonymous bitfields. 5948bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5949 QualType FieldTy, const Expr *BitWidth, 5950 bool *ZeroWidth) { 5951 // Default to true; that shouldn't confuse checks for emptiness 5952 if (ZeroWidth) 5953 *ZeroWidth = true; 5954 5955 // C99 6.7.2.1p4 - verify the field type. 5956 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5957 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5958 // Handle incomplete types with specific error. 5959 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5960 return true; 5961 if (FieldName) 5962 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5963 << FieldName << FieldTy << BitWidth->getSourceRange(); 5964 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5965 << FieldTy << BitWidth->getSourceRange(); 5966 } 5967 5968 // If the bit-width is type- or value-dependent, don't try to check 5969 // it now. 5970 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5971 return false; 5972 5973 llvm::APSInt Value; 5974 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5975 return true; 5976 5977 if (Value != 0 && ZeroWidth) 5978 *ZeroWidth = false; 5979 5980 // Zero-width bitfield is ok for anonymous field. 5981 if (Value == 0 && FieldName) 5982 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5983 5984 if (Value.isSigned() && Value.isNegative()) { 5985 if (FieldName) 5986 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5987 << FieldName << Value.toString(10); 5988 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5989 << Value.toString(10); 5990 } 5991 5992 if (!FieldTy->isDependentType()) { 5993 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5994 if (Value.getZExtValue() > TypeSize) { 5995 if (!getLangOptions().CPlusPlus) { 5996 if (FieldName) 5997 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5998 << FieldName << (unsigned)Value.getZExtValue() 5999 << (unsigned)TypeSize; 6000 6001 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6002 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6003 } 6004 6005 if (FieldName) 6006 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6007 << FieldName << (unsigned)Value.getZExtValue() 6008 << (unsigned)TypeSize; 6009 else 6010 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6011 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6012 } 6013 } 6014 6015 return false; 6016} 6017 6018/// ActOnField - Each field of a struct/union/class is passed into this in order 6019/// to create a FieldDecl object for it. 6020Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6021 SourceLocation DeclStart, 6022 Declarator &D, ExprTy *BitfieldWidth) { 6023 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6024 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6025 AS_public); 6026 return Res; 6027} 6028 6029/// HandleField - Analyze a field of a C struct or a C++ data member. 6030/// 6031FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6032 SourceLocation DeclStart, 6033 Declarator &D, Expr *BitWidth, 6034 AccessSpecifier AS) { 6035 IdentifierInfo *II = D.getIdentifier(); 6036 SourceLocation Loc = DeclStart; 6037 if (II) Loc = D.getIdentifierLoc(); 6038 6039 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6040 QualType T = TInfo->getType(); 6041 if (getLangOptions().CPlusPlus) 6042 CheckExtraCXXDefaultArguments(D); 6043 6044 DiagnoseFunctionSpecifiers(D); 6045 6046 if (D.getDeclSpec().isThreadSpecified()) 6047 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6048 6049 // Check to see if this name was declared as a member previously 6050 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6051 LookupName(Previous, S); 6052 assert((Previous.empty() || Previous.isOverloadedResult() || 6053 Previous.isSingleResult()) 6054 && "Lookup of member name should be either overloaded, single or null"); 6055 6056 // If the name is overloaded then get any declaration else get the single result 6057 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6058 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6059 6060 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6061 // Maybe we will complain about the shadowed template parameter. 6062 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6063 // Just pretend that we didn't see the previous declaration. 6064 PrevDecl = 0; 6065 } 6066 6067 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6068 PrevDecl = 0; 6069 6070 bool Mutable 6071 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6072 SourceLocation TSSL = D.getSourceRange().getBegin(); 6073 FieldDecl *NewFD 6074 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6075 AS, PrevDecl, &D); 6076 6077 if (NewFD->isInvalidDecl()) 6078 Record->setInvalidDecl(); 6079 6080 if (NewFD->isInvalidDecl() && PrevDecl) { 6081 // Don't introduce NewFD into scope; there's already something 6082 // with the same name in the same scope. 6083 } else if (II) { 6084 PushOnScopeChains(NewFD, S); 6085 } else 6086 Record->addDecl(NewFD); 6087 6088 return NewFD; 6089} 6090 6091/// \brief Build a new FieldDecl and check its well-formedness. 6092/// 6093/// This routine builds a new FieldDecl given the fields name, type, 6094/// record, etc. \p PrevDecl should refer to any previous declaration 6095/// with the same name and in the same scope as the field to be 6096/// created. 6097/// 6098/// \returns a new FieldDecl. 6099/// 6100/// \todo The Declarator argument is a hack. It will be removed once 6101FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6102 TypeSourceInfo *TInfo, 6103 RecordDecl *Record, SourceLocation Loc, 6104 bool Mutable, Expr *BitWidth, 6105 SourceLocation TSSL, 6106 AccessSpecifier AS, NamedDecl *PrevDecl, 6107 Declarator *D) { 6108 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6109 bool InvalidDecl = false; 6110 if (D) InvalidDecl = D->isInvalidType(); 6111 6112 // If we receive a broken type, recover by assuming 'int' and 6113 // marking this declaration as invalid. 6114 if (T.isNull()) { 6115 InvalidDecl = true; 6116 T = Context.IntTy; 6117 } 6118 6119 QualType EltTy = Context.getBaseElementType(T); 6120 if (!EltTy->isDependentType() && 6121 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6122 // Fields of incomplete type force their record to be invalid. 6123 Record->setInvalidDecl(); 6124 InvalidDecl = true; 6125 } 6126 6127 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6128 // than a variably modified type. 6129 if (!InvalidDecl && T->isVariablyModifiedType()) { 6130 bool SizeIsNegative; 6131 llvm::APSInt Oversized; 6132 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6133 SizeIsNegative, 6134 Oversized); 6135 if (!FixedTy.isNull()) { 6136 Diag(Loc, diag::warn_illegal_constant_array_size); 6137 T = FixedTy; 6138 } else { 6139 if (SizeIsNegative) 6140 Diag(Loc, diag::err_typecheck_negative_array_size); 6141 else if (Oversized.getBoolValue()) 6142 Diag(Loc, diag::err_array_too_large) 6143 << Oversized.toString(10); 6144 else 6145 Diag(Loc, diag::err_typecheck_field_variable_size); 6146 InvalidDecl = true; 6147 } 6148 } 6149 6150 // Fields can not have abstract class types 6151 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6152 diag::err_abstract_type_in_decl, 6153 AbstractFieldType)) 6154 InvalidDecl = true; 6155 6156 bool ZeroWidth = false; 6157 // If this is declared as a bit-field, check the bit-field. 6158 if (!InvalidDecl && BitWidth && 6159 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6160 InvalidDecl = true; 6161 BitWidth = 0; 6162 ZeroWidth = false; 6163 } 6164 6165 // Check that 'mutable' is consistent with the type of the declaration. 6166 if (!InvalidDecl && Mutable) { 6167 unsigned DiagID = 0; 6168 if (T->isReferenceType()) 6169 DiagID = diag::err_mutable_reference; 6170 else if (T.isConstQualified()) 6171 DiagID = diag::err_mutable_const; 6172 6173 if (DiagID) { 6174 SourceLocation ErrLoc = Loc; 6175 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6176 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6177 Diag(ErrLoc, DiagID); 6178 Mutable = false; 6179 InvalidDecl = true; 6180 } 6181 } 6182 6183 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6184 BitWidth, Mutable); 6185 if (InvalidDecl) 6186 NewFD->setInvalidDecl(); 6187 6188 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6189 Diag(Loc, diag::err_duplicate_member) << II; 6190 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6191 NewFD->setInvalidDecl(); 6192 } 6193 6194 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6195 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 6196 6197 if (!T->isPODType()) 6198 CXXRecord->setPOD(false); 6199 if (!ZeroWidth) 6200 CXXRecord->setEmpty(false); 6201 if (T->isReferenceType()) 6202 CXXRecord->setHasTrivialConstructor(false); 6203 6204 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6205 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6206 if (RDecl->getDefinition()) { 6207 if (!RDecl->hasTrivialConstructor()) 6208 CXXRecord->setHasTrivialConstructor(false); 6209 if (!RDecl->hasTrivialCopyConstructor()) 6210 CXXRecord->setHasTrivialCopyConstructor(false); 6211 if (!RDecl->hasTrivialCopyAssignment()) 6212 CXXRecord->setHasTrivialCopyAssignment(false); 6213 if (!RDecl->hasTrivialDestructor()) 6214 CXXRecord->setHasTrivialDestructor(false); 6215 6216 // C++ 9.5p1: An object of a class with a non-trivial 6217 // constructor, a non-trivial copy constructor, a non-trivial 6218 // destructor, or a non-trivial copy assignment operator 6219 // cannot be a member of a union, nor can an array of such 6220 // objects. 6221 // TODO: C++0x alters this restriction significantly. 6222 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6223 NewFD->setInvalidDecl(); 6224 } 6225 } 6226 } 6227 6228 // FIXME: We need to pass in the attributes given an AST 6229 // representation, not a parser representation. 6230 if (D) 6231 // FIXME: What to pass instead of TUScope? 6232 ProcessDeclAttributes(TUScope, NewFD, *D); 6233 6234 if (T.isObjCGCWeak()) 6235 Diag(Loc, diag::warn_attribute_weak_on_field); 6236 6237 NewFD->setAccess(AS); 6238 6239 // C++ [dcl.init.aggr]p1: 6240 // An aggregate is an array or a class (clause 9) with [...] no 6241 // private or protected non-static data members (clause 11). 6242 // A POD must be an aggregate. 6243 if (getLangOptions().CPlusPlus && 6244 (AS == AS_private || AS == AS_protected)) { 6245 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 6246 CXXRecord->setAggregate(false); 6247 CXXRecord->setPOD(false); 6248 } 6249 6250 return NewFD; 6251} 6252 6253bool Sema::CheckNontrivialField(FieldDecl *FD) { 6254 assert(FD); 6255 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6256 6257 if (FD->isInvalidDecl()) 6258 return true; 6259 6260 QualType EltTy = Context.getBaseElementType(FD->getType()); 6261 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6262 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6263 if (RDecl->getDefinition()) { 6264 // We check for copy constructors before constructors 6265 // because otherwise we'll never get complaints about 6266 // copy constructors. 6267 6268 CXXSpecialMember member = CXXInvalid; 6269 if (!RDecl->hasTrivialCopyConstructor()) 6270 member = CXXCopyConstructor; 6271 else if (!RDecl->hasTrivialConstructor()) 6272 member = CXXConstructor; 6273 else if (!RDecl->hasTrivialCopyAssignment()) 6274 member = CXXCopyAssignment; 6275 else if (!RDecl->hasTrivialDestructor()) 6276 member = CXXDestructor; 6277 6278 if (member != CXXInvalid) { 6279 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6280 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6281 DiagnoseNontrivial(RT, member); 6282 return true; 6283 } 6284 } 6285 } 6286 6287 return false; 6288} 6289 6290/// DiagnoseNontrivial - Given that a class has a non-trivial 6291/// special member, figure out why. 6292void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6293 QualType QT(T, 0U); 6294 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6295 6296 // Check whether the member was user-declared. 6297 switch (member) { 6298 case CXXInvalid: 6299 break; 6300 6301 case CXXConstructor: 6302 if (RD->hasUserDeclaredConstructor()) { 6303 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6304 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6305 const FunctionDecl *body = 0; 6306 ci->hasBody(body); 6307 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6308 SourceLocation CtorLoc = ci->getLocation(); 6309 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6310 return; 6311 } 6312 } 6313 6314 assert(0 && "found no user-declared constructors"); 6315 return; 6316 } 6317 break; 6318 6319 case CXXCopyConstructor: 6320 if (RD->hasUserDeclaredCopyConstructor()) { 6321 SourceLocation CtorLoc = 6322 RD->getCopyConstructor(Context, 0)->getLocation(); 6323 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6324 return; 6325 } 6326 break; 6327 6328 case CXXCopyAssignment: 6329 if (RD->hasUserDeclaredCopyAssignment()) { 6330 // FIXME: this should use the location of the copy 6331 // assignment, not the type. 6332 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6333 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6334 return; 6335 } 6336 break; 6337 6338 case CXXDestructor: 6339 if (RD->hasUserDeclaredDestructor()) { 6340 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6341 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6342 return; 6343 } 6344 break; 6345 } 6346 6347 typedef CXXRecordDecl::base_class_iterator base_iter; 6348 6349 // Virtual bases and members inhibit trivial copying/construction, 6350 // but not trivial destruction. 6351 if (member != CXXDestructor) { 6352 // Check for virtual bases. vbases includes indirect virtual bases, 6353 // so we just iterate through the direct bases. 6354 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6355 if (bi->isVirtual()) { 6356 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6357 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6358 return; 6359 } 6360 6361 // Check for virtual methods. 6362 typedef CXXRecordDecl::method_iterator meth_iter; 6363 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6364 ++mi) { 6365 if (mi->isVirtual()) { 6366 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6367 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6368 return; 6369 } 6370 } 6371 } 6372 6373 bool (CXXRecordDecl::*hasTrivial)() const; 6374 switch (member) { 6375 case CXXConstructor: 6376 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6377 case CXXCopyConstructor: 6378 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6379 case CXXCopyAssignment: 6380 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6381 case CXXDestructor: 6382 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6383 default: 6384 assert(0 && "unexpected special member"); return; 6385 } 6386 6387 // Check for nontrivial bases (and recurse). 6388 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6389 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6390 assert(BaseRT && "Don't know how to handle dependent bases"); 6391 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6392 if (!(BaseRecTy->*hasTrivial)()) { 6393 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6394 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6395 DiagnoseNontrivial(BaseRT, member); 6396 return; 6397 } 6398 } 6399 6400 // Check for nontrivial members (and recurse). 6401 typedef RecordDecl::field_iterator field_iter; 6402 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6403 ++fi) { 6404 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6405 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6406 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6407 6408 if (!(EltRD->*hasTrivial)()) { 6409 SourceLocation FLoc = (*fi)->getLocation(); 6410 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6411 DiagnoseNontrivial(EltRT, member); 6412 return; 6413 } 6414 } 6415 } 6416 6417 assert(0 && "found no explanation for non-trivial member"); 6418} 6419 6420/// TranslateIvarVisibility - Translate visibility from a token ID to an 6421/// AST enum value. 6422static ObjCIvarDecl::AccessControl 6423TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6424 switch (ivarVisibility) { 6425 default: assert(0 && "Unknown visitibility kind"); 6426 case tok::objc_private: return ObjCIvarDecl::Private; 6427 case tok::objc_public: return ObjCIvarDecl::Public; 6428 case tok::objc_protected: return ObjCIvarDecl::Protected; 6429 case tok::objc_package: return ObjCIvarDecl::Package; 6430 } 6431} 6432 6433/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6434/// in order to create an IvarDecl object for it. 6435Decl *Sema::ActOnIvar(Scope *S, 6436 SourceLocation DeclStart, 6437 Decl *IntfDecl, 6438 Declarator &D, ExprTy *BitfieldWidth, 6439 tok::ObjCKeywordKind Visibility) { 6440 6441 IdentifierInfo *II = D.getIdentifier(); 6442 Expr *BitWidth = (Expr*)BitfieldWidth; 6443 SourceLocation Loc = DeclStart; 6444 if (II) Loc = D.getIdentifierLoc(); 6445 6446 // FIXME: Unnamed fields can be handled in various different ways, for 6447 // example, unnamed unions inject all members into the struct namespace! 6448 6449 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6450 QualType T = TInfo->getType(); 6451 6452 if (BitWidth) { 6453 // 6.7.2.1p3, 6.7.2.1p4 6454 if (VerifyBitField(Loc, II, T, BitWidth)) { 6455 D.setInvalidType(); 6456 BitWidth = 0; 6457 } 6458 } else { 6459 // Not a bitfield. 6460 6461 // validate II. 6462 6463 } 6464 if (T->isReferenceType()) { 6465 Diag(Loc, diag::err_ivar_reference_type); 6466 D.setInvalidType(); 6467 } 6468 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6469 // than a variably modified type. 6470 else if (T->isVariablyModifiedType()) { 6471 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6472 D.setInvalidType(); 6473 } 6474 6475 // Get the visibility (access control) for this ivar. 6476 ObjCIvarDecl::AccessControl ac = 6477 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6478 : ObjCIvarDecl::None; 6479 // Must set ivar's DeclContext to its enclosing interface. 6480 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6481 ObjCContainerDecl *EnclosingContext; 6482 if (ObjCImplementationDecl *IMPDecl = 6483 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6484 if (!LangOpts.ObjCNonFragileABI2) { 6485 // Case of ivar declared in an implementation. Context is that of its class. 6486 EnclosingContext = IMPDecl->getClassInterface(); 6487 assert(EnclosingContext && "Implementation has no class interface!"); 6488 } 6489 else 6490 EnclosingContext = EnclosingDecl; 6491 } else { 6492 if (ObjCCategoryDecl *CDecl = 6493 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6494 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6495 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6496 return 0; 6497 } 6498 } 6499 EnclosingContext = EnclosingDecl; 6500 } 6501 6502 // Construct the decl. 6503 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6504 EnclosingContext, Loc, II, T, 6505 TInfo, ac, (Expr *)BitfieldWidth); 6506 6507 if (II) { 6508 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6509 ForRedeclaration); 6510 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6511 && !isa<TagDecl>(PrevDecl)) { 6512 Diag(Loc, diag::err_duplicate_member) << II; 6513 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6514 NewID->setInvalidDecl(); 6515 } 6516 } 6517 6518 // Process attributes attached to the ivar. 6519 ProcessDeclAttributes(S, NewID, D); 6520 6521 if (D.isInvalidType()) 6522 NewID->setInvalidDecl(); 6523 6524 if (II) { 6525 // FIXME: When interfaces are DeclContexts, we'll need to add 6526 // these to the interface. 6527 S->AddDecl(NewID); 6528 IdResolver.AddDecl(NewID); 6529 } 6530 6531 return NewID; 6532} 6533 6534/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6535/// class and class extensions. For every class @interface and class 6536/// extension @interface, if the last ivar is a bitfield of any type, 6537/// then add an implicit `char :0` ivar to the end of that interface. 6538void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6539 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6540 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6541 return; 6542 6543 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6544 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6545 6546 if (!Ivar->isBitField()) 6547 return; 6548 uint64_t BitFieldSize = 6549 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6550 if (BitFieldSize == 0) 6551 return; 6552 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6553 if (!ID) { 6554 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6555 if (!CD->IsClassExtension()) 6556 return; 6557 } 6558 // No need to add this to end of @implementation. 6559 else 6560 return; 6561 } 6562 // All conditions are met. Add a new bitfield to the tail end of ivars. 6563 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6564 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 6565 6566 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6567 DeclLoc, 0, 6568 Context.CharTy, 6569 Context.CreateTypeSourceInfo(Context.CharTy), 6570 ObjCIvarDecl::Private, BW, 6571 true); 6572 AllIvarDecls.push_back(Ivar); 6573} 6574 6575void Sema::ActOnFields(Scope* S, 6576 SourceLocation RecLoc, Decl *EnclosingDecl, 6577 Decl **Fields, unsigned NumFields, 6578 SourceLocation LBrac, SourceLocation RBrac, 6579 AttributeList *Attr) { 6580 assert(EnclosingDecl && "missing record or interface decl"); 6581 6582 // If the decl this is being inserted into is invalid, then it may be a 6583 // redeclaration or some other bogus case. Don't try to add fields to it. 6584 if (EnclosingDecl->isInvalidDecl()) { 6585 // FIXME: Deallocate fields? 6586 return; 6587 } 6588 6589 6590 // Verify that all the fields are okay. 6591 unsigned NumNamedMembers = 0; 6592 llvm::SmallVector<FieldDecl*, 32> RecFields; 6593 6594 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6595 for (unsigned i = 0; i != NumFields; ++i) { 6596 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6597 6598 // Get the type for the field. 6599 Type *FDTy = FD->getType().getTypePtr(); 6600 6601 if (!FD->isAnonymousStructOrUnion()) { 6602 // Remember all fields written by the user. 6603 RecFields.push_back(FD); 6604 } 6605 6606 // If the field is already invalid for some reason, don't emit more 6607 // diagnostics about it. 6608 if (FD->isInvalidDecl()) { 6609 EnclosingDecl->setInvalidDecl(); 6610 continue; 6611 } 6612 6613 // C99 6.7.2.1p2: 6614 // A structure or union shall not contain a member with 6615 // incomplete or function type (hence, a structure shall not 6616 // contain an instance of itself, but may contain a pointer to 6617 // an instance of itself), except that the last member of a 6618 // structure with more than one named member may have incomplete 6619 // array type; such a structure (and any union containing, 6620 // possibly recursively, a member that is such a structure) 6621 // shall not be a member of a structure or an element of an 6622 // array. 6623 if (FDTy->isFunctionType()) { 6624 // Field declared as a function. 6625 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6626 << FD->getDeclName(); 6627 FD->setInvalidDecl(); 6628 EnclosingDecl->setInvalidDecl(); 6629 continue; 6630 } else if (FDTy->isIncompleteArrayType() && Record && 6631 ((i == NumFields - 1 && !Record->isUnion()) || 6632 (getLangOptions().Microsoft && 6633 (i == NumFields - 1 || Record->isUnion())))) { 6634 // Flexible array member. 6635 // Microsoft is more permissive regarding flexible array. 6636 // It will accept flexible array in union and also 6637 // as the sole element of a struct/class. 6638 if (getLangOptions().Microsoft) { 6639 if (Record->isUnion()) 6640 Diag(FD->getLocation(), diag::ext_flexible_array_union) 6641 << FD->getDeclName(); 6642 else if (NumFields == 1) 6643 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 6644 << FD->getDeclName() << Record->getTagKind(); 6645 } else if (NumNamedMembers < 1) { 6646 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6647 << FD->getDeclName(); 6648 FD->setInvalidDecl(); 6649 EnclosingDecl->setInvalidDecl(); 6650 continue; 6651 } 6652 if (!FD->getType()->isDependentType() && 6653 !Context.getBaseElementType(FD->getType())->isPODType()) { 6654 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6655 << FD->getDeclName() << FD->getType(); 6656 FD->setInvalidDecl(); 6657 EnclosingDecl->setInvalidDecl(); 6658 continue; 6659 } 6660 // Okay, we have a legal flexible array member at the end of the struct. 6661 if (Record) 6662 Record->setHasFlexibleArrayMember(true); 6663 } else if (!FDTy->isDependentType() && 6664 RequireCompleteType(FD->getLocation(), FD->getType(), 6665 diag::err_field_incomplete)) { 6666 // Incomplete type 6667 FD->setInvalidDecl(); 6668 EnclosingDecl->setInvalidDecl(); 6669 continue; 6670 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6671 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6672 // If this is a member of a union, then entire union becomes "flexible". 6673 if (Record && Record->isUnion()) { 6674 Record->setHasFlexibleArrayMember(true); 6675 } else { 6676 // If this is a struct/class and this is not the last element, reject 6677 // it. Note that GCC supports variable sized arrays in the middle of 6678 // structures. 6679 if (i != NumFields-1) 6680 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6681 << FD->getDeclName() << FD->getType(); 6682 else { 6683 // We support flexible arrays at the end of structs in 6684 // other structs as an extension. 6685 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6686 << FD->getDeclName(); 6687 if (Record) 6688 Record->setHasFlexibleArrayMember(true); 6689 } 6690 } 6691 } 6692 if (Record && FDTTy->getDecl()->hasObjectMember()) 6693 Record->setHasObjectMember(true); 6694 } else if (FDTy->isObjCObjectType()) { 6695 /// A field cannot be an Objective-c object 6696 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6697 FD->setInvalidDecl(); 6698 EnclosingDecl->setInvalidDecl(); 6699 continue; 6700 } else if (getLangOptions().ObjC1 && 6701 getLangOptions().getGCMode() != LangOptions::NonGC && 6702 Record && 6703 (FD->getType()->isObjCObjectPointerType() || 6704 FD->getType().isObjCGCStrong())) 6705 Record->setHasObjectMember(true); 6706 else if (Context.getAsArrayType(FD->getType())) { 6707 QualType BaseType = Context.getBaseElementType(FD->getType()); 6708 if (Record && BaseType->isRecordType() && 6709 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6710 Record->setHasObjectMember(true); 6711 } 6712 // Keep track of the number of named members. 6713 if (FD->getIdentifier()) 6714 ++NumNamedMembers; 6715 } 6716 6717 // Okay, we successfully defined 'Record'. 6718 if (Record) { 6719 Record->completeDefinition(); 6720 } else { 6721 ObjCIvarDecl **ClsFields = 6722 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6723 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6724 ID->setLocEnd(RBrac); 6725 // Add ivar's to class's DeclContext. 6726 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6727 ClsFields[i]->setLexicalDeclContext(ID); 6728 ID->addDecl(ClsFields[i]); 6729 } 6730 // Must enforce the rule that ivars in the base classes may not be 6731 // duplicates. 6732 if (ID->getSuperClass()) 6733 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6734 } else if (ObjCImplementationDecl *IMPDecl = 6735 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6736 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6737 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6738 // Ivar declared in @implementation never belongs to the implementation. 6739 // Only it is in implementation's lexical context. 6740 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6741 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6742 } else if (ObjCCategoryDecl *CDecl = 6743 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6744 // case of ivars in class extension; all other cases have been 6745 // reported as errors elsewhere. 6746 // FIXME. Class extension does not have a LocEnd field. 6747 // CDecl->setLocEnd(RBrac); 6748 // Add ivar's to class extension's DeclContext. 6749 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6750 ClsFields[i]->setLexicalDeclContext(CDecl); 6751 CDecl->addDecl(ClsFields[i]); 6752 } 6753 } 6754 } 6755 6756 if (Attr) 6757 ProcessDeclAttributeList(S, Record, Attr); 6758 6759 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6760 // set the visibility of this record. 6761 if (Record && !Record->getDeclContext()->isRecord()) 6762 AddPushedVisibilityAttribute(Record); 6763} 6764 6765/// \brief Determine whether the given integral value is representable within 6766/// the given type T. 6767static bool isRepresentableIntegerValue(ASTContext &Context, 6768 llvm::APSInt &Value, 6769 QualType T) { 6770 assert(T->isIntegralType(Context) && "Integral type required!"); 6771 unsigned BitWidth = Context.getIntWidth(T); 6772 6773 if (Value.isUnsigned() || Value.isNonNegative()) 6774 return Value.getActiveBits() < BitWidth; 6775 6776 return Value.getMinSignedBits() <= BitWidth; 6777} 6778 6779// \brief Given an integral type, return the next larger integral type 6780// (or a NULL type of no such type exists). 6781static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6782 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6783 // enum checking below. 6784 assert(T->isIntegralType(Context) && "Integral type required!"); 6785 const unsigned NumTypes = 4; 6786 QualType SignedIntegralTypes[NumTypes] = { 6787 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6788 }; 6789 QualType UnsignedIntegralTypes[NumTypes] = { 6790 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6791 Context.UnsignedLongLongTy 6792 }; 6793 6794 unsigned BitWidth = Context.getTypeSize(T); 6795 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6796 : UnsignedIntegralTypes; 6797 for (unsigned I = 0; I != NumTypes; ++I) 6798 if (Context.getTypeSize(Types[I]) > BitWidth) 6799 return Types[I]; 6800 6801 return QualType(); 6802} 6803 6804EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6805 EnumConstantDecl *LastEnumConst, 6806 SourceLocation IdLoc, 6807 IdentifierInfo *Id, 6808 Expr *Val) { 6809 unsigned IntWidth = Context.Target.getIntWidth(); 6810 llvm::APSInt EnumVal(IntWidth); 6811 QualType EltTy; 6812 if (Val) { 6813 if (Enum->isDependentType() || Val->isTypeDependent()) 6814 EltTy = Context.DependentTy; 6815 else { 6816 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6817 SourceLocation ExpLoc; 6818 if (!Val->isValueDependent() && 6819 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6820 Val = 0; 6821 } else { 6822 if (!getLangOptions().CPlusPlus) { 6823 // C99 6.7.2.2p2: 6824 // The expression that defines the value of an enumeration constant 6825 // shall be an integer constant expression that has a value 6826 // representable as an int. 6827 6828 // Complain if the value is not representable in an int. 6829 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6830 Diag(IdLoc, diag::ext_enum_value_not_int) 6831 << EnumVal.toString(10) << Val->getSourceRange() 6832 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6833 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6834 // Force the type of the expression to 'int'. 6835 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 6836 } 6837 } 6838 6839 // C++0x [dcl.enum]p5: 6840 // If the underlying type is not fixed, the type of each enumerator 6841 // is the type of its initializing value: 6842 // - If an initializer is specified for an enumerator, the 6843 // initializing value has the same type as the expression. 6844 EltTy = Val->getType(); 6845 } 6846 } 6847 } 6848 6849 if (!Val) { 6850 if (Enum->isDependentType()) 6851 EltTy = Context.DependentTy; 6852 else if (!LastEnumConst) { 6853 // C++0x [dcl.enum]p5: 6854 // If the underlying type is not fixed, the type of each enumerator 6855 // is the type of its initializing value: 6856 // - If no initializer is specified for the first enumerator, the 6857 // initializing value has an unspecified integral type. 6858 // 6859 // GCC uses 'int' for its unspecified integral type, as does 6860 // C99 6.7.2.2p3. 6861 EltTy = Context.IntTy; 6862 } else { 6863 // Assign the last value + 1. 6864 EnumVal = LastEnumConst->getInitVal(); 6865 ++EnumVal; 6866 EltTy = LastEnumConst->getType(); 6867 6868 // Check for overflow on increment. 6869 if (EnumVal < LastEnumConst->getInitVal()) { 6870 // C++0x [dcl.enum]p5: 6871 // If the underlying type is not fixed, the type of each enumerator 6872 // is the type of its initializing value: 6873 // 6874 // - Otherwise the type of the initializing value is the same as 6875 // the type of the initializing value of the preceding enumerator 6876 // unless the incremented value is not representable in that type, 6877 // in which case the type is an unspecified integral type 6878 // sufficient to contain the incremented value. If no such type 6879 // exists, the program is ill-formed. 6880 QualType T = getNextLargerIntegralType(Context, EltTy); 6881 if (T.isNull()) { 6882 // There is no integral type larger enough to represent this 6883 // value. Complain, then allow the value to wrap around. 6884 EnumVal = LastEnumConst->getInitVal(); 6885 EnumVal.zext(EnumVal.getBitWidth() * 2); 6886 Diag(IdLoc, diag::warn_enumerator_too_large) 6887 << EnumVal.toString(10); 6888 } else { 6889 EltTy = T; 6890 } 6891 6892 // Retrieve the last enumerator's value, extent that type to the 6893 // type that is supposed to be large enough to represent the incremented 6894 // value, then increment. 6895 EnumVal = LastEnumConst->getInitVal(); 6896 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6897 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6898 ++EnumVal; 6899 6900 // If we're not in C++, diagnose the overflow of enumerator values, 6901 // which in C99 means that the enumerator value is not representable in 6902 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6903 // permits enumerator values that are representable in some larger 6904 // integral type. 6905 if (!getLangOptions().CPlusPlus && !T.isNull()) 6906 Diag(IdLoc, diag::warn_enum_value_overflow); 6907 } else if (!getLangOptions().CPlusPlus && 6908 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6909 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6910 Diag(IdLoc, diag::ext_enum_value_not_int) 6911 << EnumVal.toString(10) << 1; 6912 } 6913 } 6914 } 6915 6916 if (!EltTy->isDependentType()) { 6917 // Make the enumerator value match the signedness and size of the 6918 // enumerator's type. 6919 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6920 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6921 } 6922 6923 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6924 Val, EnumVal); 6925} 6926 6927 6928Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 6929 Decl *lastEnumConst, 6930 SourceLocation IdLoc, 6931 IdentifierInfo *Id, 6932 SourceLocation EqualLoc, ExprTy *val) { 6933 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 6934 EnumConstantDecl *LastEnumConst = 6935 cast_or_null<EnumConstantDecl>(lastEnumConst); 6936 Expr *Val = static_cast<Expr*>(val); 6937 6938 // The scope passed in may not be a decl scope. Zip up the scope tree until 6939 // we find one that is. 6940 S = getNonFieldDeclScope(S); 6941 6942 // Verify that there isn't already something declared with this name in this 6943 // scope. 6944 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6945 ForRedeclaration); 6946 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6947 // Maybe we will complain about the shadowed template parameter. 6948 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6949 // Just pretend that we didn't see the previous declaration. 6950 PrevDecl = 0; 6951 } 6952 6953 if (PrevDecl) { 6954 // When in C++, we may get a TagDecl with the same name; in this case the 6955 // enum constant will 'hide' the tag. 6956 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6957 "Received TagDecl when not in C++!"); 6958 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6959 if (isa<EnumConstantDecl>(PrevDecl)) 6960 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6961 else 6962 Diag(IdLoc, diag::err_redefinition) << Id; 6963 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6964 return 0; 6965 } 6966 } 6967 6968 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6969 IdLoc, Id, Val); 6970 6971 // Register this decl in the current scope stack. 6972 if (New) { 6973 New->setAccess(TheEnumDecl->getAccess()); 6974 PushOnScopeChains(New, S); 6975 } 6976 6977 return New; 6978} 6979 6980void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6981 SourceLocation RBraceLoc, Decl *EnumDeclX, 6982 Decl **Elements, unsigned NumElements, 6983 Scope *S, AttributeList *Attr) { 6984 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 6985 QualType EnumType = Context.getTypeDeclType(Enum); 6986 6987 if (Attr) 6988 ProcessDeclAttributeList(S, Enum, Attr); 6989 6990 if (Enum->isDependentType()) { 6991 for (unsigned i = 0; i != NumElements; ++i) { 6992 EnumConstantDecl *ECD = 6993 cast_or_null<EnumConstantDecl>(Elements[i]); 6994 if (!ECD) continue; 6995 6996 ECD->setType(EnumType); 6997 } 6998 6999 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7000 return; 7001 } 7002 7003 // TODO: If the result value doesn't fit in an int, it must be a long or long 7004 // long value. ISO C does not support this, but GCC does as an extension, 7005 // emit a warning. 7006 unsigned IntWidth = Context.Target.getIntWidth(); 7007 unsigned CharWidth = Context.Target.getCharWidth(); 7008 unsigned ShortWidth = Context.Target.getShortWidth(); 7009 7010 // Verify that all the values are okay, compute the size of the values, and 7011 // reverse the list. 7012 unsigned NumNegativeBits = 0; 7013 unsigned NumPositiveBits = 0; 7014 7015 // Keep track of whether all elements have type int. 7016 bool AllElementsInt = true; 7017 7018 for (unsigned i = 0; i != NumElements; ++i) { 7019 EnumConstantDecl *ECD = 7020 cast_or_null<EnumConstantDecl>(Elements[i]); 7021 if (!ECD) continue; // Already issued a diagnostic. 7022 7023 const llvm::APSInt &InitVal = ECD->getInitVal(); 7024 7025 // Keep track of the size of positive and negative values. 7026 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7027 NumPositiveBits = std::max(NumPositiveBits, 7028 (unsigned)InitVal.getActiveBits()); 7029 else 7030 NumNegativeBits = std::max(NumNegativeBits, 7031 (unsigned)InitVal.getMinSignedBits()); 7032 7033 // Keep track of whether every enum element has type int (very commmon). 7034 if (AllElementsInt) 7035 AllElementsInt = ECD->getType() == Context.IntTy; 7036 } 7037 7038 // Figure out the type that should be used for this enum. 7039 // FIXME: Support -fshort-enums. 7040 QualType BestType; 7041 unsigned BestWidth; 7042 7043 // C++0x N3000 [conv.prom]p3: 7044 // An rvalue of an unscoped enumeration type whose underlying 7045 // type is not fixed can be converted to an rvalue of the first 7046 // of the following types that can represent all the values of 7047 // the enumeration: int, unsigned int, long int, unsigned long 7048 // int, long long int, or unsigned long long int. 7049 // C99 6.4.4.3p2: 7050 // An identifier declared as an enumeration constant has type int. 7051 // The C99 rule is modified by a gcc extension 7052 QualType BestPromotionType; 7053 7054 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7055 7056 if (NumNegativeBits) { 7057 // If there is a negative value, figure out the smallest integer type (of 7058 // int/long/longlong) that fits. 7059 // If it's packed, check also if it fits a char or a short. 7060 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7061 BestType = Context.SignedCharTy; 7062 BestWidth = CharWidth; 7063 } else if (Packed && NumNegativeBits <= ShortWidth && 7064 NumPositiveBits < ShortWidth) { 7065 BestType = Context.ShortTy; 7066 BestWidth = ShortWidth; 7067 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7068 BestType = Context.IntTy; 7069 BestWidth = IntWidth; 7070 } else { 7071 BestWidth = Context.Target.getLongWidth(); 7072 7073 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7074 BestType = Context.LongTy; 7075 } else { 7076 BestWidth = Context.Target.getLongLongWidth(); 7077 7078 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7079 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7080 BestType = Context.LongLongTy; 7081 } 7082 } 7083 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7084 } else { 7085 // If there is no negative value, figure out the smallest type that fits 7086 // all of the enumerator values. 7087 // If it's packed, check also if it fits a char or a short. 7088 if (Packed && NumPositiveBits <= CharWidth) { 7089 BestType = Context.UnsignedCharTy; 7090 BestPromotionType = Context.IntTy; 7091 BestWidth = CharWidth; 7092 } else if (Packed && NumPositiveBits <= ShortWidth) { 7093 BestType = Context.UnsignedShortTy; 7094 BestPromotionType = Context.IntTy; 7095 BestWidth = ShortWidth; 7096 } else if (NumPositiveBits <= IntWidth) { 7097 BestType = Context.UnsignedIntTy; 7098 BestWidth = IntWidth; 7099 BestPromotionType 7100 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7101 ? Context.UnsignedIntTy : Context.IntTy; 7102 } else if (NumPositiveBits <= 7103 (BestWidth = Context.Target.getLongWidth())) { 7104 BestType = Context.UnsignedLongTy; 7105 BestPromotionType 7106 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7107 ? Context.UnsignedLongTy : Context.LongTy; 7108 } else { 7109 BestWidth = Context.Target.getLongLongWidth(); 7110 assert(NumPositiveBits <= BestWidth && 7111 "How could an initializer get larger than ULL?"); 7112 BestType = Context.UnsignedLongLongTy; 7113 BestPromotionType 7114 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7115 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7116 } 7117 } 7118 7119 // Loop over all of the enumerator constants, changing their types to match 7120 // the type of the enum if needed. 7121 for (unsigned i = 0; i != NumElements; ++i) { 7122 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7123 if (!ECD) continue; // Already issued a diagnostic. 7124 7125 // Standard C says the enumerators have int type, but we allow, as an 7126 // extension, the enumerators to be larger than int size. If each 7127 // enumerator value fits in an int, type it as an int, otherwise type it the 7128 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7129 // that X has type 'int', not 'unsigned'. 7130 7131 // Determine whether the value fits into an int. 7132 llvm::APSInt InitVal = ECD->getInitVal(); 7133 7134 // If it fits into an integer type, force it. Otherwise force it to match 7135 // the enum decl type. 7136 QualType NewTy; 7137 unsigned NewWidth; 7138 bool NewSign; 7139 if (!getLangOptions().CPlusPlus && 7140 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7141 NewTy = Context.IntTy; 7142 NewWidth = IntWidth; 7143 NewSign = true; 7144 } else if (ECD->getType() == BestType) { 7145 // Already the right type! 7146 if (getLangOptions().CPlusPlus) 7147 // C++ [dcl.enum]p4: Following the closing brace of an 7148 // enum-specifier, each enumerator has the type of its 7149 // enumeration. 7150 ECD->setType(EnumType); 7151 continue; 7152 } else { 7153 NewTy = BestType; 7154 NewWidth = BestWidth; 7155 NewSign = BestType->isSignedIntegerType(); 7156 } 7157 7158 // Adjust the APSInt value. 7159 InitVal.extOrTrunc(NewWidth); 7160 InitVal.setIsSigned(NewSign); 7161 ECD->setInitVal(InitVal); 7162 7163 // Adjust the Expr initializer and type. 7164 if (ECD->getInitExpr()) 7165 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7166 CK_IntegralCast, 7167 ECD->getInitExpr(), 7168 /*base paths*/ 0, 7169 VK_RValue)); 7170 if (getLangOptions().CPlusPlus) 7171 // C++ [dcl.enum]p4: Following the closing brace of an 7172 // enum-specifier, each enumerator has the type of its 7173 // enumeration. 7174 ECD->setType(EnumType); 7175 else 7176 ECD->setType(NewTy); 7177 } 7178 7179 Enum->completeDefinition(BestType, BestPromotionType, 7180 NumPositiveBits, NumNegativeBits); 7181} 7182 7183Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7184 StringLiteral *AsmString = cast<StringLiteral>(expr); 7185 7186 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7187 Loc, AsmString); 7188 CurContext->addDecl(New); 7189 return New; 7190} 7191 7192void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7193 SourceLocation PragmaLoc, 7194 SourceLocation NameLoc) { 7195 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7196 7197 if (PrevDecl) { 7198 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7199 } else { 7200 (void)WeakUndeclaredIdentifiers.insert( 7201 std::pair<IdentifierInfo*,WeakInfo> 7202 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7203 } 7204} 7205 7206void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7207 IdentifierInfo* AliasName, 7208 SourceLocation PragmaLoc, 7209 SourceLocation NameLoc, 7210 SourceLocation AliasNameLoc) { 7211 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7212 LookupOrdinaryName); 7213 WeakInfo W = WeakInfo(Name, NameLoc); 7214 7215 if (PrevDecl) { 7216 if (!PrevDecl->hasAttr<AliasAttr>()) 7217 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7218 DeclApplyPragmaWeak(TUScope, ND, W); 7219 } else { 7220 (void)WeakUndeclaredIdentifiers.insert( 7221 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7222 } 7223} 7224