SemaDecl.cpp revision 3e9438b5251a547253d64169863c2909b9b2772a
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 Record->setUserDeclaredDestructor(true); 3935 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3936 // user-defined destructor. 3937 Record->setPOD(false); 3938 3939 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3940 // declared destructor. 3941 // FIXME: C++0x: don't do this for "= default" destructors 3942 Record->setHasTrivialDestructor(false); 3943 } else if (CXXConversionDecl *Conversion 3944 = dyn_cast<CXXConversionDecl>(NewFD)) { 3945 ActOnConversionDeclarator(Conversion); 3946 } 3947 3948 // Find any virtual functions that this function overrides. 3949 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3950 if (!Method->isFunctionTemplateSpecialization() && 3951 !Method->getDescribedFunctionTemplate()) 3952 AddOverriddenMethods(Method->getParent(), Method); 3953 } 3954 3955 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3956 if (NewFD->isOverloadedOperator() && 3957 CheckOverloadedOperatorDeclaration(NewFD)) 3958 return NewFD->setInvalidDecl(); 3959 3960 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3961 if (NewFD->getLiteralIdentifier() && 3962 CheckLiteralOperatorDeclaration(NewFD)) 3963 return NewFD->setInvalidDecl(); 3964 3965 // In C++, check default arguments now that we have merged decls. Unless 3966 // the lexical context is the class, because in this case this is done 3967 // during delayed parsing anyway. 3968 if (!CurContext->isRecord()) 3969 CheckCXXDefaultArguments(NewFD); 3970 } 3971} 3972 3973void Sema::CheckMain(FunctionDecl* FD) { 3974 // C++ [basic.start.main]p3: A program that declares main to be inline 3975 // or static is ill-formed. 3976 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3977 // shall not appear in a declaration of main. 3978 // static main is not an error under C99, but we should warn about it. 3979 bool isInline = FD->isInlineSpecified(); 3980 bool isStatic = FD->getStorageClass() == SC_Static; 3981 if (isInline || isStatic) { 3982 unsigned diagID = diag::warn_unusual_main_decl; 3983 if (isInline || getLangOptions().CPlusPlus) 3984 diagID = diag::err_unusual_main_decl; 3985 3986 int which = isStatic + (isInline << 1) - 1; 3987 Diag(FD->getLocation(), diagID) << which; 3988 } 3989 3990 QualType T = FD->getType(); 3991 assert(T->isFunctionType() && "function decl is not of function type"); 3992 const FunctionType* FT = T->getAs<FunctionType>(); 3993 3994 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3995 TypeSourceInfo *TSI = FD->getTypeSourceInfo(); 3996 TypeLoc TL = TSI->getTypeLoc(); 3997 const SemaDiagnosticBuilder& D = Diag(FD->getTypeSpecStartLoc(), 3998 diag::err_main_returns_nonint); 3999 if (FunctionTypeLoc* PTL = dyn_cast<FunctionTypeLoc>(&TL)) { 4000 D << FixItHint::CreateReplacement(PTL->getResultLoc().getSourceRange(), 4001 "int"); 4002 } 4003 FD->setInvalidDecl(true); 4004 } 4005 4006 // Treat protoless main() as nullary. 4007 if (isa<FunctionNoProtoType>(FT)) return; 4008 4009 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4010 unsigned nparams = FTP->getNumArgs(); 4011 assert(FD->getNumParams() == nparams); 4012 4013 bool HasExtraParameters = (nparams > 3); 4014 4015 // Darwin passes an undocumented fourth argument of type char**. If 4016 // other platforms start sprouting these, the logic below will start 4017 // getting shifty. 4018 if (nparams == 4 && 4019 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4020 HasExtraParameters = false; 4021 4022 if (HasExtraParameters) { 4023 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4024 FD->setInvalidDecl(true); 4025 nparams = 3; 4026 } 4027 4028 // FIXME: a lot of the following diagnostics would be improved 4029 // if we had some location information about types. 4030 4031 QualType CharPP = 4032 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4033 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4034 4035 for (unsigned i = 0; i < nparams; ++i) { 4036 QualType AT = FTP->getArgType(i); 4037 4038 bool mismatch = true; 4039 4040 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4041 mismatch = false; 4042 else if (Expected[i] == CharPP) { 4043 // As an extension, the following forms are okay: 4044 // char const ** 4045 // char const * const * 4046 // char * const * 4047 4048 QualifierCollector qs; 4049 const PointerType* PT; 4050 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4051 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4052 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4053 qs.removeConst(); 4054 mismatch = !qs.empty(); 4055 } 4056 } 4057 4058 if (mismatch) { 4059 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4060 // TODO: suggest replacing given type with expected type 4061 FD->setInvalidDecl(true); 4062 } 4063 } 4064 4065 if (nparams == 1 && !FD->isInvalidDecl()) { 4066 Diag(FD->getLocation(), diag::warn_main_one_arg); 4067 } 4068} 4069 4070bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4071 // FIXME: Need strict checking. In C89, we need to check for 4072 // any assignment, increment, decrement, function-calls, or 4073 // commas outside of a sizeof. In C99, it's the same list, 4074 // except that the aforementioned are allowed in unevaluated 4075 // expressions. Everything else falls under the 4076 // "may accept other forms of constant expressions" exception. 4077 // (We never end up here for C++, so the constant expression 4078 // rules there don't matter.) 4079 if (Init->isConstantInitializer(Context, false)) 4080 return false; 4081 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4082 << Init->getSourceRange(); 4083 return true; 4084} 4085 4086void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4087 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4088} 4089 4090/// AddInitializerToDecl - Adds the initializer Init to the 4091/// declaration dcl. If DirectInit is true, this is C++ direct 4092/// initialization rather than copy initialization. 4093void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4094 // If there is no declaration, there was an error parsing it. Just ignore 4095 // the initializer. 4096 if (RealDecl == 0) 4097 return; 4098 4099 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4100 // With declarators parsed the way they are, the parser cannot 4101 // distinguish between a normal initializer and a pure-specifier. 4102 // Thus this grotesque test. 4103 IntegerLiteral *IL; 4104 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4105 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4106 CheckPureMethod(Method, Init->getSourceRange()); 4107 else { 4108 Diag(Method->getLocation(), diag::err_member_function_initialization) 4109 << Method->getDeclName() << Init->getSourceRange(); 4110 Method->setInvalidDecl(); 4111 } 4112 return; 4113 } 4114 4115 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4116 if (!VDecl) { 4117 if (getLangOptions().CPlusPlus && 4118 RealDecl->getLexicalDeclContext()->isRecord() && 4119 isa<NamedDecl>(RealDecl)) 4120 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4121 else 4122 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4123 RealDecl->setInvalidDecl(); 4124 return; 4125 } 4126 4127 4128 4129 // A definition must end up with a complete type, which means it must be 4130 // complete with the restriction that an array type might be completed by the 4131 // initializer; note that later code assumes this restriction. 4132 QualType BaseDeclType = VDecl->getType(); 4133 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4134 BaseDeclType = Array->getElementType(); 4135 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4136 diag::err_typecheck_decl_incomplete_type)) { 4137 RealDecl->setInvalidDecl(); 4138 return; 4139 } 4140 4141 // The variable can not have an abstract class type. 4142 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4143 diag::err_abstract_type_in_decl, 4144 AbstractVariableType)) 4145 VDecl->setInvalidDecl(); 4146 4147 const VarDecl *Def; 4148 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4149 Diag(VDecl->getLocation(), diag::err_redefinition) 4150 << VDecl->getDeclName(); 4151 Diag(Def->getLocation(), diag::note_previous_definition); 4152 VDecl->setInvalidDecl(); 4153 return; 4154 } 4155 4156 // C++ [class.static.data]p4 4157 // If a static data member is of const integral or const 4158 // enumeration type, its declaration in the class definition can 4159 // specify a constant-initializer which shall be an integral 4160 // constant expression (5.19). In that case, the member can appear 4161 // in integral constant expressions. The member shall still be 4162 // defined in a namespace scope if it is used in the program and the 4163 // namespace scope definition shall not contain an initializer. 4164 // 4165 // We already performed a redefinition check above, but for static 4166 // data members we also need to check whether there was an in-class 4167 // declaration with an initializer. 4168 const VarDecl* PrevInit = 0; 4169 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4170 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4171 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4172 return; 4173 } 4174 4175 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4176 getCurFunction()->setHasBranchProtectedScope(); 4177 4178 // Capture the variable that is being initialized and the style of 4179 // initialization. 4180 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4181 4182 // FIXME: Poor source location information. 4183 InitializationKind Kind 4184 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4185 Init->getLocStart(), 4186 Init->getLocEnd()) 4187 : InitializationKind::CreateCopy(VDecl->getLocation(), 4188 Init->getLocStart()); 4189 4190 // Get the decls type and save a reference for later, since 4191 // CheckInitializerTypes may change it. 4192 QualType DclT = VDecl->getType(), SavT = DclT; 4193 if (VDecl->isBlockVarDecl()) { 4194 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4195 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4196 VDecl->setInvalidDecl(); 4197 } else if (!VDecl->isInvalidDecl()) { 4198 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4199 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4200 MultiExprArg(*this, &Init, 1), 4201 &DclT); 4202 if (Result.isInvalid()) { 4203 VDecl->setInvalidDecl(); 4204 return; 4205 } 4206 4207 Init = Result.takeAs<Expr>(); 4208 4209 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4210 // Don't check invalid declarations to avoid emitting useless diagnostics. 4211 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4212 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4213 CheckForConstantInitializer(Init, DclT); 4214 } 4215 } 4216 } else if (VDecl->isStaticDataMember() && 4217 VDecl->getLexicalDeclContext()->isRecord()) { 4218 // This is an in-class initialization for a static data member, e.g., 4219 // 4220 // struct S { 4221 // static const int value = 17; 4222 // }; 4223 4224 // Try to perform the initialization regardless. 4225 if (!VDecl->isInvalidDecl()) { 4226 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4227 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4228 MultiExprArg(*this, &Init, 1), 4229 &DclT); 4230 if (Result.isInvalid()) { 4231 VDecl->setInvalidDecl(); 4232 return; 4233 } 4234 4235 Init = Result.takeAs<Expr>(); 4236 } 4237 4238 // C++ [class.mem]p4: 4239 // A member-declarator can contain a constant-initializer only 4240 // if it declares a static member (9.4) of const integral or 4241 // const enumeration type, see 9.4.2. 4242 QualType T = VDecl->getType(); 4243 4244 // Do nothing on dependent types. 4245 if (T->isDependentType()) { 4246 4247 // Require constness. 4248 } else if (!T.isConstQualified()) { 4249 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4250 << Init->getSourceRange(); 4251 VDecl->setInvalidDecl(); 4252 4253 // We allow integer constant expressions in all cases. 4254 } else if (T->isIntegralOrEnumerationType()) { 4255 if (!Init->isValueDependent()) { 4256 // Check whether the expression is a constant expression. 4257 llvm::APSInt Value; 4258 SourceLocation Loc; 4259 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4260 Diag(Loc, diag::err_in_class_initializer_non_constant) 4261 << Init->getSourceRange(); 4262 VDecl->setInvalidDecl(); 4263 } 4264 } 4265 4266 // We allow floating-point constants as an extension in C++03, and 4267 // C++0x has far more complicated rules that we don't really 4268 // implement fully. 4269 } else { 4270 bool Allowed = false; 4271 if (getLangOptions().CPlusPlus0x) { 4272 Allowed = T->isLiteralType(); 4273 } else if (T->isFloatingType()) { // also permits complex, which is ok 4274 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4275 << T << Init->getSourceRange(); 4276 Allowed = true; 4277 } 4278 4279 if (!Allowed) { 4280 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4281 << T << Init->getSourceRange(); 4282 VDecl->setInvalidDecl(); 4283 4284 // TODO: there are probably expressions that pass here that shouldn't. 4285 } else if (!Init->isValueDependent() && 4286 !Init->isConstantInitializer(Context, false)) { 4287 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4288 << Init->getSourceRange(); 4289 VDecl->setInvalidDecl(); 4290 } 4291 } 4292 } else if (VDecl->isFileVarDecl()) { 4293 if (VDecl->getStorageClass() == SC_Extern && 4294 (!getLangOptions().CPlusPlus || 4295 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4296 Diag(VDecl->getLocation(), diag::warn_extern_init); 4297 if (!VDecl->isInvalidDecl()) { 4298 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4299 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4300 MultiExprArg(*this, &Init, 1), 4301 &DclT); 4302 if (Result.isInvalid()) { 4303 VDecl->setInvalidDecl(); 4304 return; 4305 } 4306 4307 Init = Result.takeAs<Expr>(); 4308 } 4309 4310 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4311 // Don't check invalid declarations to avoid emitting useless diagnostics. 4312 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4313 // C99 6.7.8p4. All file scoped initializers need to be constant. 4314 CheckForConstantInitializer(Init, DclT); 4315 } 4316 } 4317 // If the type changed, it means we had an incomplete type that was 4318 // completed by the initializer. For example: 4319 // int ary[] = { 1, 3, 5 }; 4320 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4321 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4322 VDecl->setType(DclT); 4323 Init->setType(DclT); 4324 } 4325 4326 Init = MaybeCreateCXXExprWithTemporaries(Init); 4327 // Attach the initializer to the decl. 4328 VDecl->setInit(Init); 4329 4330 if (getLangOptions().CPlusPlus) { 4331 if (!VDecl->isInvalidDecl() && 4332 !VDecl->getDeclContext()->isDependentContext() && 4333 VDecl->hasGlobalStorage() && !VDecl->isStaticLocal() && 4334 !Init->isConstantInitializer(Context, 4335 VDecl->getType()->isReferenceType())) 4336 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4337 << Init->getSourceRange(); 4338 4339 // Make sure we mark the destructor as used if necessary. 4340 QualType InitType = VDecl->getType(); 4341 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4342 InitType = Context.getBaseElementType(Array); 4343 if (const RecordType *Record = InitType->getAs<RecordType>()) 4344 FinalizeVarWithDestructor(VDecl, Record); 4345 } 4346 4347 return; 4348} 4349 4350/// ActOnInitializerError - Given that there was an error parsing an 4351/// initializer for the given declaration, try to return to some form 4352/// of sanity. 4353void Sema::ActOnInitializerError(Decl *D) { 4354 // Our main concern here is re-establishing invariants like "a 4355 // variable's type is either dependent or complete". 4356 if (!D || D->isInvalidDecl()) return; 4357 4358 VarDecl *VD = dyn_cast<VarDecl>(D); 4359 if (!VD) return; 4360 4361 QualType Ty = VD->getType(); 4362 if (Ty->isDependentType()) return; 4363 4364 // Require a complete type. 4365 if (RequireCompleteType(VD->getLocation(), 4366 Context.getBaseElementType(Ty), 4367 diag::err_typecheck_decl_incomplete_type)) { 4368 VD->setInvalidDecl(); 4369 return; 4370 } 4371 4372 // Require an abstract type. 4373 if (RequireNonAbstractType(VD->getLocation(), Ty, 4374 diag::err_abstract_type_in_decl, 4375 AbstractVariableType)) { 4376 VD->setInvalidDecl(); 4377 return; 4378 } 4379 4380 // Don't bother complaining about constructors or destructors, 4381 // though. 4382} 4383 4384void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4385 bool TypeContainsUndeducedAuto) { 4386 // If there is no declaration, there was an error parsing it. Just ignore it. 4387 if (RealDecl == 0) 4388 return; 4389 4390 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4391 QualType Type = Var->getType(); 4392 4393 // C++0x [dcl.spec.auto]p3 4394 if (TypeContainsUndeducedAuto) { 4395 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4396 << Var->getDeclName() << Type; 4397 Var->setInvalidDecl(); 4398 return; 4399 } 4400 4401 switch (Var->isThisDeclarationADefinition()) { 4402 case VarDecl::Definition: 4403 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4404 break; 4405 4406 // We have an out-of-line definition of a static data member 4407 // that has an in-class initializer, so we type-check this like 4408 // a declaration. 4409 // 4410 // Fall through 4411 4412 case VarDecl::DeclarationOnly: 4413 // It's only a declaration. 4414 4415 // Block scope. C99 6.7p7: If an identifier for an object is 4416 // declared with no linkage (C99 6.2.2p6), the type for the 4417 // object shall be complete. 4418 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4419 !Var->getLinkage() && !Var->isInvalidDecl() && 4420 RequireCompleteType(Var->getLocation(), Type, 4421 diag::err_typecheck_decl_incomplete_type)) 4422 Var->setInvalidDecl(); 4423 4424 // Make sure that the type is not abstract. 4425 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4426 RequireNonAbstractType(Var->getLocation(), Type, 4427 diag::err_abstract_type_in_decl, 4428 AbstractVariableType)) 4429 Var->setInvalidDecl(); 4430 return; 4431 4432 case VarDecl::TentativeDefinition: 4433 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4434 // object that has file scope without an initializer, and without a 4435 // storage-class specifier or with the storage-class specifier "static", 4436 // constitutes a tentative definition. Note: A tentative definition with 4437 // external linkage is valid (C99 6.2.2p5). 4438 if (!Var->isInvalidDecl()) { 4439 if (const IncompleteArrayType *ArrayT 4440 = Context.getAsIncompleteArrayType(Type)) { 4441 if (RequireCompleteType(Var->getLocation(), 4442 ArrayT->getElementType(), 4443 diag::err_illegal_decl_array_incomplete_type)) 4444 Var->setInvalidDecl(); 4445 } else if (Var->getStorageClass() == SC_Static) { 4446 // C99 6.9.2p3: If the declaration of an identifier for an object is 4447 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4448 // declared type shall not be an incomplete type. 4449 // NOTE: code such as the following 4450 // static struct s; 4451 // struct s { int a; }; 4452 // is accepted by gcc. Hence here we issue a warning instead of 4453 // an error and we do not invalidate the static declaration. 4454 // NOTE: to avoid multiple warnings, only check the first declaration. 4455 if (Var->getPreviousDeclaration() == 0) 4456 RequireCompleteType(Var->getLocation(), Type, 4457 diag::ext_typecheck_decl_incomplete_type); 4458 } 4459 } 4460 4461 // Record the tentative definition; we're done. 4462 if (!Var->isInvalidDecl()) 4463 TentativeDefinitions.push_back(Var); 4464 return; 4465 } 4466 4467 // Provide a specific diagnostic for uninitialized variable 4468 // definitions with incomplete array type. 4469 if (Type->isIncompleteArrayType()) { 4470 Diag(Var->getLocation(), 4471 diag::err_typecheck_incomplete_array_needs_initializer); 4472 Var->setInvalidDecl(); 4473 return; 4474 } 4475 4476 // Provide a specific diagnostic for uninitialized variable 4477 // definitions with reference type. 4478 if (Type->isReferenceType()) { 4479 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4480 << Var->getDeclName() 4481 << SourceRange(Var->getLocation(), Var->getLocation()); 4482 Var->setInvalidDecl(); 4483 return; 4484 } 4485 4486 // Do not attempt to type-check the default initializer for a 4487 // variable with dependent type. 4488 if (Type->isDependentType()) 4489 return; 4490 4491 if (Var->isInvalidDecl()) 4492 return; 4493 4494 if (RequireCompleteType(Var->getLocation(), 4495 Context.getBaseElementType(Type), 4496 diag::err_typecheck_decl_incomplete_type)) { 4497 Var->setInvalidDecl(); 4498 return; 4499 } 4500 4501 // The variable can not have an abstract class type. 4502 if (RequireNonAbstractType(Var->getLocation(), Type, 4503 diag::err_abstract_type_in_decl, 4504 AbstractVariableType)) { 4505 Var->setInvalidDecl(); 4506 return; 4507 } 4508 4509 const RecordType *Record 4510 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4511 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4512 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4513 // C++03 [dcl.init]p9: 4514 // If no initializer is specified for an object, and the 4515 // object is of (possibly cv-qualified) non-POD class type (or 4516 // array thereof), the object shall be default-initialized; if 4517 // the object is of const-qualified type, the underlying class 4518 // type shall have a user-declared default 4519 // constructor. Otherwise, if no initializer is specified for 4520 // a non- static object, the object and its subobjects, if 4521 // any, have an indeterminate initial value); if the object 4522 // or any of its subobjects are of const-qualified type, the 4523 // program is ill-formed. 4524 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4525 } else { 4526 // Check for jumps past the implicit initializer. C++0x 4527 // clarifies that this applies to a "variable with automatic 4528 // storage duration", not a "local variable". 4529 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4530 getCurFunction()->setHasBranchProtectedScope(); 4531 4532 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4533 InitializationKind Kind 4534 = InitializationKind::CreateDefault(Var->getLocation()); 4535 4536 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4537 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4538 MultiExprArg(*this, 0, 0)); 4539 if (Init.isInvalid()) 4540 Var->setInvalidDecl(); 4541 else if (Init.get()) { 4542 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4543 4544 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4545 Var->hasGlobalStorage() && !Var->isStaticLocal() && 4546 !Var->getDeclContext()->isDependentContext() && 4547 !Var->getInit()->isConstantInitializer(Context, false)) 4548 Diag(Var->getLocation(), diag::warn_global_constructor); 4549 } 4550 } 4551 4552 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4553 FinalizeVarWithDestructor(Var, Record); 4554 } 4555} 4556 4557Sema::DeclGroupPtrTy 4558Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4559 Decl **Group, unsigned NumDecls) { 4560 llvm::SmallVector<Decl*, 8> Decls; 4561 4562 if (DS.isTypeSpecOwned()) 4563 Decls.push_back(DS.getRepAsDecl()); 4564 4565 for (unsigned i = 0; i != NumDecls; ++i) 4566 if (Decl *D = Group[i]) 4567 Decls.push_back(D); 4568 4569 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4570 Decls.data(), Decls.size())); 4571} 4572 4573 4574/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4575/// to introduce parameters into function prototype scope. 4576Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4577 const DeclSpec &DS = D.getDeclSpec(); 4578 4579 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4580 VarDecl::StorageClass StorageClass = SC_None; 4581 VarDecl::StorageClass StorageClassAsWritten = SC_None; 4582 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4583 StorageClass = SC_Register; 4584 StorageClassAsWritten = SC_Register; 4585 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4586 Diag(DS.getStorageClassSpecLoc(), 4587 diag::err_invalid_storage_class_in_func_decl); 4588 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4589 } 4590 4591 if (D.getDeclSpec().isThreadSpecified()) 4592 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4593 4594 DiagnoseFunctionSpecifiers(D); 4595 4596 // Check that there are no default arguments inside the type of this 4597 // parameter (C++ only). 4598 if (getLangOptions().CPlusPlus) 4599 CheckExtraCXXDefaultArguments(D); 4600 4601 TagDecl *OwnedDecl = 0; 4602 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4603 QualType parmDeclType = TInfo->getType(); 4604 4605 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4606 // C++ [dcl.fct]p6: 4607 // Types shall not be defined in return or parameter types. 4608 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4609 << Context.getTypeDeclType(OwnedDecl); 4610 } 4611 4612 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4613 IdentifierInfo *II = D.getIdentifier(); 4614 if (II) { 4615 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4616 ForRedeclaration); 4617 LookupName(R, S); 4618 if (R.isSingleResult()) { 4619 NamedDecl *PrevDecl = R.getFoundDecl(); 4620 if (PrevDecl->isTemplateParameter()) { 4621 // Maybe we will complain about the shadowed template parameter. 4622 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4623 // Just pretend that we didn't see the previous declaration. 4624 PrevDecl = 0; 4625 } else if (S->isDeclScope(PrevDecl)) { 4626 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4627 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4628 4629 // Recover by removing the name 4630 II = 0; 4631 D.SetIdentifier(0, D.getIdentifierLoc()); 4632 D.setInvalidType(true); 4633 } 4634 } 4635 } 4636 4637 // Temporarily put parameter variables in the translation unit, not 4638 // the enclosing context. This prevents them from accidentally 4639 // looking like class members in C++. 4640 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4641 TInfo, parmDeclType, II, 4642 D.getIdentifierLoc(), 4643 StorageClass, StorageClassAsWritten); 4644 4645 if (D.isInvalidType()) 4646 New->setInvalidDecl(); 4647 4648 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4649 if (D.getCXXScopeSpec().isSet()) { 4650 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4651 << D.getCXXScopeSpec().getRange(); 4652 New->setInvalidDecl(); 4653 } 4654 4655 // Add the parameter declaration into this scope. 4656 S->AddDecl(New); 4657 if (II) 4658 IdResolver.AddDecl(New); 4659 4660 ProcessDeclAttributes(S, New, D); 4661 4662 if (New->hasAttr<BlocksAttr>()) { 4663 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4664 } 4665 return New; 4666} 4667 4668/// \brief Synthesizes a variable for a parameter arising from a 4669/// typedef. 4670ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4671 SourceLocation Loc, 4672 QualType T) { 4673 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4674 T, Context.getTrivialTypeSourceInfo(T, Loc), 4675 SC_None, SC_None, 0); 4676 Param->setImplicit(); 4677 return Param; 4678} 4679 4680void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 4681 ParmVarDecl * const *ParamEnd) { 4682 if (Diags.getDiagnosticLevel(diag::warn_unused_parameter) == 4683 Diagnostic::Ignored) 4684 return; 4685 4686 // Don't diagnose unused-parameter errors in template instantiations; we 4687 // will already have done so in the template itself. 4688 if (!ActiveTemplateInstantiations.empty()) 4689 return; 4690 4691 for (; Param != ParamEnd; ++Param) { 4692 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 4693 !(*Param)->hasAttr<UnusedAttr>()) { 4694 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 4695 << (*Param)->getDeclName(); 4696 } 4697 } 4698} 4699 4700ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4701 TypeSourceInfo *TSInfo, QualType T, 4702 IdentifierInfo *Name, 4703 SourceLocation NameLoc, 4704 VarDecl::StorageClass StorageClass, 4705 VarDecl::StorageClass StorageClassAsWritten) { 4706 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4707 adjustParameterType(T), TSInfo, 4708 StorageClass, StorageClassAsWritten, 4709 0); 4710 4711 // Parameters can not be abstract class types. 4712 // For record types, this is done by the AbstractClassUsageDiagnoser once 4713 // the class has been completely parsed. 4714 if (!CurContext->isRecord() && 4715 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4716 AbstractParamType)) 4717 New->setInvalidDecl(); 4718 4719 // Parameter declarators cannot be interface types. All ObjC objects are 4720 // passed by reference. 4721 if (T->isObjCObjectType()) { 4722 Diag(NameLoc, 4723 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4724 New->setInvalidDecl(); 4725 } 4726 4727 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4728 // duration shall not be qualified by an address-space qualifier." 4729 // Since all parameters have automatic store duration, they can not have 4730 // an address space. 4731 if (T.getAddressSpace() != 0) { 4732 Diag(NameLoc, diag::err_arg_with_address_space); 4733 New->setInvalidDecl(); 4734 } 4735 4736 return New; 4737} 4738 4739void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4740 SourceLocation LocAfterDecls) { 4741 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4742 "Not a function declarator!"); 4743 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4744 4745 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4746 // for a K&R function. 4747 if (!FTI.hasPrototype) { 4748 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4749 --i; 4750 if (FTI.ArgInfo[i].Param == 0) { 4751 llvm::SmallString<256> Code; 4752 llvm::raw_svector_ostream(Code) << " int " 4753 << FTI.ArgInfo[i].Ident->getName() 4754 << ";\n"; 4755 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4756 << FTI.ArgInfo[i].Ident 4757 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4758 4759 // Implicitly declare the argument as type 'int' for lack of a better 4760 // type. 4761 DeclSpec DS; 4762 const char* PrevSpec; // unused 4763 unsigned DiagID; // unused 4764 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4765 PrevSpec, DiagID); 4766 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4767 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4768 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4769 } 4770 } 4771 } 4772} 4773 4774Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4775 Declarator &D) { 4776 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4777 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4778 "Not a function declarator!"); 4779 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4780 4781 if (FTI.hasPrototype) { 4782 // FIXME: Diagnose arguments without names in C. 4783 } 4784 4785 Scope *ParentScope = FnBodyScope->getParent(); 4786 4787 Decl *DP = HandleDeclarator(ParentScope, D, 4788 MultiTemplateParamsArg(*this), 4789 /*IsFunctionDefinition=*/true); 4790 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4791} 4792 4793static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4794 // Don't warn about invalid declarations. 4795 if (FD->isInvalidDecl()) 4796 return false; 4797 4798 // Or declarations that aren't global. 4799 if (!FD->isGlobal()) 4800 return false; 4801 4802 // Don't warn about C++ member functions. 4803 if (isa<CXXMethodDecl>(FD)) 4804 return false; 4805 4806 // Don't warn about 'main'. 4807 if (FD->isMain()) 4808 return false; 4809 4810 // Don't warn about inline functions. 4811 if (FD->isInlineSpecified()) 4812 return false; 4813 4814 // Don't warn about function templates. 4815 if (FD->getDescribedFunctionTemplate()) 4816 return false; 4817 4818 // Don't warn about function template specializations. 4819 if (FD->isFunctionTemplateSpecialization()) 4820 return false; 4821 4822 bool MissingPrototype = true; 4823 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4824 Prev; Prev = Prev->getPreviousDeclaration()) { 4825 // Ignore any declarations that occur in function or method 4826 // scope, because they aren't visible from the header. 4827 if (Prev->getDeclContext()->isFunctionOrMethod()) 4828 continue; 4829 4830 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4831 break; 4832 } 4833 4834 return MissingPrototype; 4835} 4836 4837Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4838 // Clear the last template instantiation error context. 4839 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4840 4841 if (!D) 4842 return D; 4843 FunctionDecl *FD = 0; 4844 4845 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4846 FD = FunTmpl->getTemplatedDecl(); 4847 else 4848 FD = cast<FunctionDecl>(D); 4849 4850 // Enter a new function scope 4851 PushFunctionScope(); 4852 4853 // See if this is a redefinition. 4854 // But don't complain if we're in GNU89 mode and the previous definition 4855 // was an extern inline function. 4856 const FunctionDecl *Definition; 4857 if (FD->hasBody(Definition) && 4858 !canRedefineFunction(Definition, getLangOptions())) { 4859 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 4860 Definition->getStorageClass() == SC_Extern) 4861 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 4862 << FD->getDeclName() << getLangOptions().CPlusPlus; 4863 else 4864 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4865 Diag(Definition->getLocation(), diag::note_previous_definition); 4866 } 4867 4868 // Builtin functions cannot be defined. 4869 if (unsigned BuiltinID = FD->getBuiltinID()) { 4870 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4871 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4872 FD->setInvalidDecl(); 4873 } 4874 } 4875 4876 // The return type of a function definition must be complete 4877 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4878 QualType ResultType = FD->getResultType(); 4879 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4880 !FD->isInvalidDecl() && 4881 RequireCompleteType(FD->getLocation(), ResultType, 4882 diag::err_func_def_incomplete_result)) 4883 FD->setInvalidDecl(); 4884 4885 // GNU warning -Wmissing-prototypes: 4886 // Warn if a global function is defined without a previous 4887 // prototype declaration. This warning is issued even if the 4888 // definition itself provides a prototype. The aim is to detect 4889 // global functions that fail to be declared in header files. 4890 if (ShouldWarnAboutMissingPrototype(FD)) 4891 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4892 4893 if (FnBodyScope) 4894 PushDeclContext(FnBodyScope, FD); 4895 4896 // Check the validity of our function parameters 4897 CheckParmsForFunctionDef(FD); 4898 4899 bool ShouldCheckShadow = 4900 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4901 4902 // Introduce our parameters into the function scope 4903 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4904 ParmVarDecl *Param = FD->getParamDecl(p); 4905 Param->setOwningFunction(FD); 4906 4907 // If this has an identifier, add it to the scope stack. 4908 if (Param->getIdentifier() && FnBodyScope) { 4909 if (ShouldCheckShadow) 4910 CheckShadow(FnBodyScope, Param); 4911 4912 PushOnScopeChains(Param, FnBodyScope); 4913 } 4914 } 4915 4916 // Checking attributes of current function definition 4917 // dllimport attribute. 4918 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 4919 if (DA && (!FD->getAttr<DLLExportAttr>())) { 4920 // dllimport attribute cannot be directly applied to definition. 4921 if (!DA->isInherited()) { 4922 Diag(FD->getLocation(), 4923 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4924 << "dllimport"; 4925 FD->setInvalidDecl(); 4926 return FD; 4927 } 4928 4929 // Visual C++ appears to not think this is an issue, so only issue 4930 // a warning when Microsoft extensions are disabled. 4931 if (!LangOpts.Microsoft) { 4932 // If a symbol previously declared dllimport is later defined, the 4933 // attribute is ignored in subsequent references, and a warning is 4934 // emitted. 4935 Diag(FD->getLocation(), 4936 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4937 << FD->getName() << "dllimport"; 4938 } 4939 } 4940 return FD; 4941} 4942 4943/// \brief Given the set of return statements within a function body, 4944/// compute the variables that are subject to the named return value 4945/// optimization. 4946/// 4947/// Each of the variables that is subject to the named return value 4948/// optimization will be marked as NRVO variables in the AST, and any 4949/// return statement that has a marked NRVO variable as its NRVO candidate can 4950/// use the named return value optimization. 4951/// 4952/// This function applies a very simplistic algorithm for NRVO: if every return 4953/// statement in the function has the same NRVO candidate, that candidate is 4954/// the NRVO variable. 4955/// 4956/// FIXME: Employ a smarter algorithm that accounts for multiple return 4957/// statements and the lifetimes of the NRVO candidates. We should be able to 4958/// find a maximal set of NRVO variables. 4959static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 4960 ReturnStmt **Returns = Scope->Returns.data(); 4961 4962 const VarDecl *NRVOCandidate = 0; 4963 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 4964 if (!Returns[I]->getNRVOCandidate()) 4965 return; 4966 4967 if (!NRVOCandidate) 4968 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4969 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4970 return; 4971 } 4972 4973 if (NRVOCandidate) 4974 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4975} 4976 4977Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 4978 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4979} 4980 4981Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 4982 bool IsInstantiation) { 4983 FunctionDecl *FD = 0; 4984 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4985 if (FunTmpl) 4986 FD = FunTmpl->getTemplatedDecl(); 4987 else 4988 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4989 4990 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4991 4992 if (FD) { 4993 FD->setBody(Body); 4994 if (FD->isMain()) { 4995 // C and C++ allow for main to automagically return 0. 4996 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4997 FD->setHasImplicitReturnZero(true); 4998 WP.disableCheckFallThrough(); 4999 } 5000 5001 if (!FD->isInvalidDecl()) { 5002 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5003 5004 // If this is a constructor, we need a vtable. 5005 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5006 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5007 5008 ComputeNRVO(Body, getCurFunction()); 5009 } 5010 5011 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5012 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5013 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5014 MD->setBody(Body); 5015 MD->setEndLoc(Body->getLocEnd()); 5016 if (!MD->isInvalidDecl()) 5017 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5018 } else { 5019 return 0; 5020 } 5021 5022 // Verify and clean out per-function state. 5023 5024 // Check goto/label use. 5025 FunctionScopeInfo *CurFn = getCurFunction(); 5026 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 5027 I = CurFn->LabelMap.begin(), E = CurFn->LabelMap.end(); I != E; ++I) { 5028 LabelStmt *L = I->second; 5029 5030 // Verify that we have no forward references left. If so, there was a goto 5031 // or address of a label taken, but no definition of it. Label fwd 5032 // definitions are indicated with a null substmt. 5033 if (L->getSubStmt() != 0) { 5034 if (!L->isUsed()) 5035 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 5036 continue; 5037 } 5038 5039 // Emit error. 5040 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 5041 5042 // At this point, we have gotos that use the bogus label. Stitch it into 5043 // the function body so that they aren't leaked and that the AST is well 5044 // formed. 5045 if (Body == 0) { 5046 // The whole function wasn't parsed correctly. 5047 continue; 5048 } 5049 5050 // Otherwise, the body is valid: we want to stitch the label decl into the 5051 // function somewhere so that it is properly owned and so that the goto 5052 // has a valid target. Do this by creating a new compound stmt with the 5053 // label in it. 5054 5055 // Give the label a sub-statement. 5056 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 5057 5058 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 5059 cast<CXXTryStmt>(Body)->getTryBlock() : 5060 cast<CompoundStmt>(Body); 5061 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 5062 Compound->body_end()); 5063 Elements.push_back(L); 5064 Compound->setStmts(Context, Elements.data(), Elements.size()); 5065 } 5066 5067 if (Body) { 5068 // C++ constructors that have function-try-blocks can't have return 5069 // statements in the handlers of that block. (C++ [except.handle]p14) 5070 // Verify this. 5071 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5072 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5073 5074 // Verify that that gotos and switch cases don't jump into scopes illegally. 5075 // Verify that that gotos and switch cases don't jump into scopes illegally. 5076 if (getCurFunction()->NeedsScopeChecking() && 5077 !dcl->isInvalidDecl() && 5078 !hasAnyErrorsInThisFunction()) 5079 DiagnoseInvalidJumps(Body); 5080 5081 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5082 if (!Destructor->getParent()->isDependentType()) 5083 CheckDestructor(Destructor); 5084 5085 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5086 Destructor->getParent()); 5087 } 5088 5089 // If any errors have occurred, clear out any temporaries that may have 5090 // been leftover. This ensures that these temporaries won't be picked up for 5091 // deletion in some later function. 5092 if (PP.getDiagnostics().hasErrorOccurred()) 5093 ExprTemporaries.clear(); 5094 else if (!isa<FunctionTemplateDecl>(dcl)) { 5095 // Since the body is valid, issue any analysis-based warnings that are 5096 // enabled. 5097 QualType ResultType; 5098 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 5099 AnalysisWarnings.IssueWarnings(WP, FD); 5100 } else { 5101 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 5102 AnalysisWarnings.IssueWarnings(WP, MD); 5103 } 5104 } 5105 5106 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5107 } 5108 5109 if (!IsInstantiation) 5110 PopDeclContext(); 5111 5112 PopFunctionOrBlockScope(); 5113 5114 // If any errors have occurred, clear out any temporaries that may have 5115 // been leftover. This ensures that these temporaries won't be picked up for 5116 // deletion in some later function. 5117 if (getDiagnostics().hasErrorOccurred()) 5118 ExprTemporaries.clear(); 5119 5120 return dcl; 5121} 5122 5123/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5124/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5125NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5126 IdentifierInfo &II, Scope *S) { 5127 // Before we produce a declaration for an implicitly defined 5128 // function, see whether there was a locally-scoped declaration of 5129 // this name as a function or variable. If so, use that 5130 // (non-visible) declaration, and complain about it. 5131 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5132 = LocallyScopedExternalDecls.find(&II); 5133 if (Pos != LocallyScopedExternalDecls.end()) { 5134 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5135 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5136 return Pos->second; 5137 } 5138 5139 // Extension in C99. Legal in C90, but warn about it. 5140 if (II.getName().startswith("__builtin_")) 5141 Diag(Loc, diag::warn_builtin_unknown) << &II; 5142 else if (getLangOptions().C99) 5143 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5144 else 5145 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5146 5147 // Set a Declarator for the implicit definition: int foo(); 5148 const char *Dummy; 5149 DeclSpec DS; 5150 unsigned DiagID; 5151 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5152 Error = Error; // Silence warning. 5153 assert(!Error && "Error setting up implicit decl!"); 5154 Declarator D(DS, Declarator::BlockContext); 5155 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5156 0, 0, false, SourceLocation(), 5157 false, 0,0,0, Loc, Loc, D), 5158 SourceLocation()); 5159 D.SetIdentifier(&II, Loc); 5160 5161 // Insert this function into translation-unit scope. 5162 5163 DeclContext *PrevDC = CurContext; 5164 CurContext = Context.getTranslationUnitDecl(); 5165 5166 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5167 FD->setImplicit(); 5168 5169 CurContext = PrevDC; 5170 5171 AddKnownFunctionAttributes(FD); 5172 5173 return FD; 5174} 5175 5176/// \brief Adds any function attributes that we know a priori based on 5177/// the declaration of this function. 5178/// 5179/// These attributes can apply both to implicitly-declared builtins 5180/// (like __builtin___printf_chk) or to library-declared functions 5181/// like NSLog or printf. 5182void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5183 if (FD->isInvalidDecl()) 5184 return; 5185 5186 // If this is a built-in function, map its builtin attributes to 5187 // actual attributes. 5188 if (unsigned BuiltinID = FD->getBuiltinID()) { 5189 // Handle printf-formatting attributes. 5190 unsigned FormatIdx; 5191 bool HasVAListArg; 5192 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5193 if (!FD->getAttr<FormatAttr>()) 5194 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5195 "printf", FormatIdx+1, 5196 HasVAListArg ? 0 : FormatIdx+2)); 5197 } 5198 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5199 HasVAListArg)) { 5200 if (!FD->getAttr<FormatAttr>()) 5201 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5202 "scanf", FormatIdx+1, 5203 HasVAListArg ? 0 : FormatIdx+2)); 5204 } 5205 5206 // Mark const if we don't care about errno and that is the only 5207 // thing preventing the function from being const. This allows 5208 // IRgen to use LLVM intrinsics for such functions. 5209 if (!getLangOptions().MathErrno && 5210 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5211 if (!FD->getAttr<ConstAttr>()) 5212 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5213 } 5214 5215 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5216 FD->setType(Context.getNoReturnType(FD->getType())); 5217 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5218 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5219 if (Context.BuiltinInfo.isConst(BuiltinID)) 5220 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5221 } 5222 5223 IdentifierInfo *Name = FD->getIdentifier(); 5224 if (!Name) 5225 return; 5226 if ((!getLangOptions().CPlusPlus && 5227 FD->getDeclContext()->isTranslationUnit()) || 5228 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5229 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5230 LinkageSpecDecl::lang_c)) { 5231 // Okay: this could be a libc/libm/Objective-C function we know 5232 // about. 5233 } else 5234 return; 5235 5236 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5237 // FIXME: NSLog and NSLogv should be target specific 5238 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5239 // FIXME: We known better than our headers. 5240 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5241 } else 5242 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5243 "printf", 1, 5244 Name->isStr("NSLogv") ? 0 : 2)); 5245 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5246 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5247 // target-specific builtins, perhaps? 5248 if (!FD->getAttr<FormatAttr>()) 5249 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5250 "printf", 2, 5251 Name->isStr("vasprintf") ? 0 : 3)); 5252 } 5253} 5254 5255TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5256 TypeSourceInfo *TInfo) { 5257 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5258 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5259 5260 if (!TInfo) { 5261 assert(D.isInvalidType() && "no declarator info for valid type"); 5262 TInfo = Context.getTrivialTypeSourceInfo(T); 5263 } 5264 5265 // Scope manipulation handled by caller. 5266 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5267 D.getIdentifierLoc(), 5268 D.getIdentifier(), 5269 TInfo); 5270 5271 if (const TagType *TT = T->getAs<TagType>()) { 5272 TagDecl *TD = TT->getDecl(); 5273 5274 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5275 // keep track of the TypedefDecl. 5276 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5277 TD->setTypedefForAnonDecl(NewTD); 5278 } 5279 5280 if (D.isInvalidType()) 5281 NewTD->setInvalidDecl(); 5282 return NewTD; 5283} 5284 5285 5286/// \brief Determine whether a tag with a given kind is acceptable 5287/// as a redeclaration of the given tag declaration. 5288/// 5289/// \returns true if the new tag kind is acceptable, false otherwise. 5290bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5291 TagTypeKind NewTag, 5292 SourceLocation NewTagLoc, 5293 const IdentifierInfo &Name) { 5294 // C++ [dcl.type.elab]p3: 5295 // The class-key or enum keyword present in the 5296 // elaborated-type-specifier shall agree in kind with the 5297 // declaration to which the name in the elaborated-type-specifier 5298 // refers. This rule also applies to the form of 5299 // elaborated-type-specifier that declares a class-name or 5300 // friend class since it can be construed as referring to the 5301 // definition of the class. Thus, in any 5302 // elaborated-type-specifier, the enum keyword shall be used to 5303 // refer to an enumeration (7.2), the union class-key shall be 5304 // used to refer to a union (clause 9), and either the class or 5305 // struct class-key shall be used to refer to a class (clause 9) 5306 // declared using the class or struct class-key. 5307 TagTypeKind OldTag = Previous->getTagKind(); 5308 if (OldTag == NewTag) 5309 return true; 5310 5311 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5312 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5313 // Warn about the struct/class tag mismatch. 5314 bool isTemplate = false; 5315 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5316 isTemplate = Record->getDescribedClassTemplate(); 5317 5318 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5319 << (NewTag == TTK_Class) 5320 << isTemplate << &Name 5321 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5322 OldTag == TTK_Class? "class" : "struct"); 5323 Diag(Previous->getLocation(), diag::note_previous_use); 5324 return true; 5325 } 5326 return false; 5327} 5328 5329/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5330/// former case, Name will be non-null. In the later case, Name will be null. 5331/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5332/// reference/declaration/definition of a tag. 5333Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5334 SourceLocation KWLoc, CXXScopeSpec &SS, 5335 IdentifierInfo *Name, SourceLocation NameLoc, 5336 AttributeList *Attr, AccessSpecifier AS, 5337 MultiTemplateParamsArg TemplateParameterLists, 5338 bool &OwnedDecl, bool &IsDependent) { 5339 // If this is not a definition, it must have a name. 5340 assert((Name != 0 || TUK == TUK_Definition) && 5341 "Nameless record must be a definition!"); 5342 5343 OwnedDecl = false; 5344 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5345 5346 // FIXME: Check explicit specializations more carefully. 5347 bool isExplicitSpecialization = false; 5348 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5349 bool Invalid = false; 5350 if (TUK != TUK_Reference) { 5351 if (TemplateParameterList *TemplateParams 5352 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5353 (TemplateParameterList**)TemplateParameterLists.get(), 5354 TemplateParameterLists.size(), 5355 TUK == TUK_Friend, 5356 isExplicitSpecialization, 5357 Invalid)) { 5358 // All but one template parameter lists have been matching. 5359 --NumMatchedTemplateParamLists; 5360 5361 if (TemplateParams->size() > 0) { 5362 // This is a declaration or definition of a class template (which may 5363 // be a member of another template). 5364 if (Invalid) 5365 return 0; 5366 5367 OwnedDecl = false; 5368 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5369 SS, Name, NameLoc, Attr, 5370 TemplateParams, 5371 AS); 5372 TemplateParameterLists.release(); 5373 return Result.get(); 5374 } else { 5375 // The "template<>" header is extraneous. 5376 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5377 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5378 isExplicitSpecialization = true; 5379 } 5380 } 5381 } 5382 5383 DeclContext *SearchDC = CurContext; 5384 DeclContext *DC = CurContext; 5385 bool isStdBadAlloc = false; 5386 5387 RedeclarationKind Redecl = ForRedeclaration; 5388 if (TUK == TUK_Friend || TUK == TUK_Reference) 5389 Redecl = NotForRedeclaration; 5390 5391 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5392 5393 if (Name && SS.isNotEmpty()) { 5394 // We have a nested-name tag ('struct foo::bar'). 5395 5396 // Check for invalid 'foo::'. 5397 if (SS.isInvalid()) { 5398 Name = 0; 5399 goto CreateNewDecl; 5400 } 5401 5402 // If this is a friend or a reference to a class in a dependent 5403 // context, don't try to make a decl for it. 5404 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5405 DC = computeDeclContext(SS, false); 5406 if (!DC) { 5407 IsDependent = true; 5408 return 0; 5409 } 5410 } else { 5411 DC = computeDeclContext(SS, true); 5412 if (!DC) { 5413 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5414 << SS.getRange(); 5415 return 0; 5416 } 5417 } 5418 5419 if (RequireCompleteDeclContext(SS, DC)) 5420 return 0; 5421 5422 SearchDC = DC; 5423 // Look-up name inside 'foo::'. 5424 LookupQualifiedName(Previous, DC); 5425 5426 if (Previous.isAmbiguous()) 5427 return 0; 5428 5429 if (Previous.empty()) { 5430 // Name lookup did not find anything. However, if the 5431 // nested-name-specifier refers to the current instantiation, 5432 // and that current instantiation has any dependent base 5433 // classes, we might find something at instantiation time: treat 5434 // this as a dependent elaborated-type-specifier. 5435 if (Previous.wasNotFoundInCurrentInstantiation()) { 5436 IsDependent = true; 5437 return 0; 5438 } 5439 5440 // A tag 'foo::bar' must already exist. 5441 Diag(NameLoc, diag::err_not_tag_in_scope) 5442 << Kind << Name << DC << SS.getRange(); 5443 Name = 0; 5444 Invalid = true; 5445 goto CreateNewDecl; 5446 } 5447 } else if (Name) { 5448 // If this is a named struct, check to see if there was a previous forward 5449 // declaration or definition. 5450 // FIXME: We're looking into outer scopes here, even when we 5451 // shouldn't be. Doing so can result in ambiguities that we 5452 // shouldn't be diagnosing. 5453 LookupName(Previous, S); 5454 5455 // Note: there used to be some attempt at recovery here. 5456 if (Previous.isAmbiguous()) 5457 return 0; 5458 5459 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5460 // FIXME: This makes sure that we ignore the contexts associated 5461 // with C structs, unions, and enums when looking for a matching 5462 // tag declaration or definition. See the similar lookup tweak 5463 // in Sema::LookupName; is there a better way to deal with this? 5464 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5465 SearchDC = SearchDC->getParent(); 5466 } 5467 } else if (S->isFunctionPrototypeScope()) { 5468 // If this is an enum declaration in function prototype scope, set its 5469 // initial context to the translation unit. 5470 SearchDC = Context.getTranslationUnitDecl(); 5471 } 5472 5473 if (Previous.isSingleResult() && 5474 Previous.getFoundDecl()->isTemplateParameter()) { 5475 // Maybe we will complain about the shadowed template parameter. 5476 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5477 // Just pretend that we didn't see the previous declaration. 5478 Previous.clear(); 5479 } 5480 5481 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5482 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5483 // This is a declaration of or a reference to "std::bad_alloc". 5484 isStdBadAlloc = true; 5485 5486 if (Previous.empty() && StdBadAlloc) { 5487 // std::bad_alloc has been implicitly declared (but made invisible to 5488 // name lookup). Fill in this implicit declaration as the previous 5489 // declaration, so that the declarations get chained appropriately. 5490 Previous.addDecl(getStdBadAlloc()); 5491 } 5492 } 5493 5494 // If we didn't find a previous declaration, and this is a reference 5495 // (or friend reference), move to the correct scope. In C++, we 5496 // also need to do a redeclaration lookup there, just in case 5497 // there's a shadow friend decl. 5498 if (Name && Previous.empty() && 5499 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5500 if (Invalid) goto CreateNewDecl; 5501 assert(SS.isEmpty()); 5502 5503 if (TUK == TUK_Reference) { 5504 // C++ [basic.scope.pdecl]p5: 5505 // -- for an elaborated-type-specifier of the form 5506 // 5507 // class-key identifier 5508 // 5509 // if the elaborated-type-specifier is used in the 5510 // decl-specifier-seq or parameter-declaration-clause of a 5511 // function defined in namespace scope, the identifier is 5512 // declared as a class-name in the namespace that contains 5513 // the declaration; otherwise, except as a friend 5514 // declaration, the identifier is declared in the smallest 5515 // non-class, non-function-prototype scope that contains the 5516 // declaration. 5517 // 5518 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5519 // C structs and unions. 5520 // 5521 // It is an error in C++ to declare (rather than define) an enum 5522 // type, including via an elaborated type specifier. We'll 5523 // diagnose that later; for now, declare the enum in the same 5524 // scope as we would have picked for any other tag type. 5525 // 5526 // GNU C also supports this behavior as part of its incomplete 5527 // enum types extension, while GNU C++ does not. 5528 // 5529 // Find the context where we'll be declaring the tag. 5530 // FIXME: We would like to maintain the current DeclContext as the 5531 // lexical context, 5532 while (SearchDC->isRecord()) 5533 SearchDC = SearchDC->getParent(); 5534 5535 // Find the scope where we'll be declaring the tag. 5536 while (S->isClassScope() || 5537 (getLangOptions().CPlusPlus && 5538 S->isFunctionPrototypeScope()) || 5539 ((S->getFlags() & Scope::DeclScope) == 0) || 5540 (S->getEntity() && 5541 ((DeclContext *)S->getEntity())->isTransparentContext())) 5542 S = S->getParent(); 5543 } else { 5544 assert(TUK == TUK_Friend); 5545 // C++ [namespace.memdef]p3: 5546 // If a friend declaration in a non-local class first declares a 5547 // class or function, the friend class or function is a member of 5548 // the innermost enclosing namespace. 5549 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5550 } 5551 5552 // In C++, we need to do a redeclaration lookup to properly 5553 // diagnose some problems. 5554 if (getLangOptions().CPlusPlus) { 5555 Previous.setRedeclarationKind(ForRedeclaration); 5556 LookupQualifiedName(Previous, SearchDC); 5557 } 5558 } 5559 5560 if (!Previous.empty()) { 5561 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5562 5563 // It's okay to have a tag decl in the same scope as a typedef 5564 // which hides a tag decl in the same scope. Finding this 5565 // insanity with a redeclaration lookup can only actually happen 5566 // in C++. 5567 // 5568 // This is also okay for elaborated-type-specifiers, which is 5569 // technically forbidden by the current standard but which is 5570 // okay according to the likely resolution of an open issue; 5571 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5572 if (getLangOptions().CPlusPlus) { 5573 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5574 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5575 TagDecl *Tag = TT->getDecl(); 5576 if (Tag->getDeclName() == Name && 5577 Tag->getDeclContext()->getRedeclContext() 5578 ->Equals(TD->getDeclContext()->getRedeclContext())) { 5579 PrevDecl = Tag; 5580 Previous.clear(); 5581 Previous.addDecl(Tag); 5582 Previous.resolveKind(); 5583 } 5584 } 5585 } 5586 } 5587 5588 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5589 // If this is a use of a previous tag, or if the tag is already declared 5590 // in the same scope (so that the definition/declaration completes or 5591 // rementions the tag), reuse the decl. 5592 if (TUK == TUK_Reference || TUK == TUK_Friend || 5593 isDeclInScope(PrevDecl, SearchDC, S)) { 5594 // Make sure that this wasn't declared as an enum and now used as a 5595 // struct or something similar. 5596 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5597 bool SafeToContinue 5598 = (PrevTagDecl->getTagKind() != TTK_Enum && 5599 Kind != TTK_Enum); 5600 if (SafeToContinue) 5601 Diag(KWLoc, diag::err_use_with_wrong_tag) 5602 << Name 5603 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5604 PrevTagDecl->getKindName()); 5605 else 5606 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5607 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5608 5609 if (SafeToContinue) 5610 Kind = PrevTagDecl->getTagKind(); 5611 else { 5612 // Recover by making this an anonymous redefinition. 5613 Name = 0; 5614 Previous.clear(); 5615 Invalid = true; 5616 } 5617 } 5618 5619 if (!Invalid) { 5620 // If this is a use, just return the declaration we found. 5621 5622 // FIXME: In the future, return a variant or some other clue 5623 // for the consumer of this Decl to know it doesn't own it. 5624 // For our current ASTs this shouldn't be a problem, but will 5625 // need to be changed with DeclGroups. 5626 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5627 TUK == TUK_Friend) 5628 return PrevTagDecl; 5629 5630 // Diagnose attempts to redefine a tag. 5631 if (TUK == TUK_Definition) { 5632 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5633 // If we're defining a specialization and the previous definition 5634 // is from an implicit instantiation, don't emit an error 5635 // here; we'll catch this in the general case below. 5636 if (!isExplicitSpecialization || 5637 !isa<CXXRecordDecl>(Def) || 5638 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5639 == TSK_ExplicitSpecialization) { 5640 Diag(NameLoc, diag::err_redefinition) << Name; 5641 Diag(Def->getLocation(), diag::note_previous_definition); 5642 // If this is a redefinition, recover by making this 5643 // struct be anonymous, which will make any later 5644 // references get the previous definition. 5645 Name = 0; 5646 Previous.clear(); 5647 Invalid = true; 5648 } 5649 } else { 5650 // If the type is currently being defined, complain 5651 // about a nested redefinition. 5652 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5653 if (Tag->isBeingDefined()) { 5654 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5655 Diag(PrevTagDecl->getLocation(), 5656 diag::note_previous_definition); 5657 Name = 0; 5658 Previous.clear(); 5659 Invalid = true; 5660 } 5661 } 5662 5663 // Okay, this is definition of a previously declared or referenced 5664 // tag PrevDecl. We're going to create a new Decl for it. 5665 } 5666 } 5667 // If we get here we have (another) forward declaration or we 5668 // have a definition. Just create a new decl. 5669 5670 } else { 5671 // If we get here, this is a definition of a new tag type in a nested 5672 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5673 // new decl/type. We set PrevDecl to NULL so that the entities 5674 // have distinct types. 5675 Previous.clear(); 5676 } 5677 // If we get here, we're going to create a new Decl. If PrevDecl 5678 // is non-NULL, it's a definition of the tag declared by 5679 // PrevDecl. If it's NULL, we have a new definition. 5680 5681 5682 // Otherwise, PrevDecl is not a tag, but was found with tag 5683 // lookup. This is only actually possible in C++, where a few 5684 // things like templates still live in the tag namespace. 5685 } else { 5686 assert(getLangOptions().CPlusPlus); 5687 5688 // Use a better diagnostic if an elaborated-type-specifier 5689 // found the wrong kind of type on the first 5690 // (non-redeclaration) lookup. 5691 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5692 !Previous.isForRedeclaration()) { 5693 unsigned Kind = 0; 5694 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5695 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5696 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5697 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5698 Invalid = true; 5699 5700 // Otherwise, only diagnose if the declaration is in scope. 5701 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5702 // do nothing 5703 5704 // Diagnose implicit declarations introduced by elaborated types. 5705 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5706 unsigned Kind = 0; 5707 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5708 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5709 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5710 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5711 Invalid = true; 5712 5713 // Otherwise it's a declaration. Call out a particularly common 5714 // case here. 5715 } else if (isa<TypedefDecl>(PrevDecl)) { 5716 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5717 << Name 5718 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5719 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5720 Invalid = true; 5721 5722 // Otherwise, diagnose. 5723 } else { 5724 // The tag name clashes with something else in the target scope, 5725 // issue an error and recover by making this tag be anonymous. 5726 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5727 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5728 Name = 0; 5729 Invalid = true; 5730 } 5731 5732 // The existing declaration isn't relevant to us; we're in a 5733 // new scope, so clear out the previous declaration. 5734 Previous.clear(); 5735 } 5736 } 5737 5738CreateNewDecl: 5739 5740 TagDecl *PrevDecl = 0; 5741 if (Previous.isSingleResult()) 5742 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5743 5744 // If there is an identifier, use the location of the identifier as the 5745 // location of the decl, otherwise use the location of the struct/union 5746 // keyword. 5747 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5748 5749 // Otherwise, create a new declaration. If there is a previous 5750 // declaration of the same entity, the two will be linked via 5751 // PrevDecl. 5752 TagDecl *New; 5753 5754 if (Kind == TTK_Enum) { 5755 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5756 // enum X { A, B, C } D; D should chain to X. 5757 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5758 cast_or_null<EnumDecl>(PrevDecl)); 5759 // If this is an undefined enum, warn. 5760 if (TUK != TUK_Definition && !Invalid) { 5761 TagDecl *Def; 5762 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5763 Diag(Loc, diag::ext_forward_ref_enum_def) 5764 << New; 5765 Diag(Def->getLocation(), diag::note_previous_definition); 5766 } else { 5767 unsigned DiagID = diag::ext_forward_ref_enum; 5768 if (getLangOptions().Microsoft) 5769 DiagID = diag::ext_ms_forward_ref_enum; 5770 else if (getLangOptions().CPlusPlus) 5771 DiagID = diag::err_forward_ref_enum; 5772 Diag(Loc, DiagID); 5773 } 5774 } 5775 } else { 5776 // struct/union/class 5777 5778 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5779 // struct X { int A; } D; D should chain to X. 5780 if (getLangOptions().CPlusPlus) { 5781 // FIXME: Look for a way to use RecordDecl for simple structs. 5782 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5783 cast_or_null<CXXRecordDecl>(PrevDecl)); 5784 5785 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5786 StdBadAlloc = cast<CXXRecordDecl>(New); 5787 } else 5788 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5789 cast_or_null<RecordDecl>(PrevDecl)); 5790 } 5791 5792 // Maybe add qualifier info. 5793 if (SS.isNotEmpty()) { 5794 if (SS.isSet()) { 5795 NestedNameSpecifier *NNS 5796 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5797 New->setQualifierInfo(NNS, SS.getRange()); 5798 if (NumMatchedTemplateParamLists > 0) { 5799 New->setTemplateParameterListsInfo(Context, 5800 NumMatchedTemplateParamLists, 5801 (TemplateParameterList**) TemplateParameterLists.release()); 5802 } 5803 } 5804 else 5805 Invalid = true; 5806 } 5807 5808 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5809 // Add alignment attributes if necessary; these attributes are checked when 5810 // the ASTContext lays out the structure. 5811 // 5812 // It is important for implementing the correct semantics that this 5813 // happen here (in act on tag decl). The #pragma pack stack is 5814 // maintained as a result of parser callbacks which can occur at 5815 // many points during the parsing of a struct declaration (because 5816 // the #pragma tokens are effectively skipped over during the 5817 // parsing of the struct). 5818 AddAlignmentAttributesForRecord(RD); 5819 } 5820 5821 // If this is a specialization of a member class (of a class template), 5822 // check the specialization. 5823 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5824 Invalid = true; 5825 5826 if (Invalid) 5827 New->setInvalidDecl(); 5828 5829 if (Attr) 5830 ProcessDeclAttributeList(S, New, Attr); 5831 5832 // If we're declaring or defining a tag in function prototype scope 5833 // in C, note that this type can only be used within the function. 5834 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5835 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5836 5837 // Set the lexical context. If the tag has a C++ scope specifier, the 5838 // lexical context will be different from the semantic context. 5839 New->setLexicalDeclContext(CurContext); 5840 5841 // Mark this as a friend decl if applicable. 5842 if (TUK == TUK_Friend) 5843 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5844 5845 // Set the access specifier. 5846 if (!Invalid && SearchDC->isRecord()) 5847 SetMemberAccessSpecifier(New, PrevDecl, AS); 5848 5849 if (TUK == TUK_Definition) 5850 New->startDefinition(); 5851 5852 // If this has an identifier, add it to the scope stack. 5853 if (TUK == TUK_Friend) { 5854 // We might be replacing an existing declaration in the lookup tables; 5855 // if so, borrow its access specifier. 5856 if (PrevDecl) 5857 New->setAccess(PrevDecl->getAccess()); 5858 5859 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 5860 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5861 if (Name) // can be null along some error paths 5862 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5863 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5864 } else if (Name) { 5865 S = getNonFieldDeclScope(S); 5866 PushOnScopeChains(New, S); 5867 } else { 5868 CurContext->addDecl(New); 5869 } 5870 5871 // If this is the C FILE type, notify the AST context. 5872 if (IdentifierInfo *II = New->getIdentifier()) 5873 if (!New->isInvalidDecl() && 5874 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 5875 II->isStr("FILE")) 5876 Context.setFILEDecl(New); 5877 5878 OwnedDecl = true; 5879 return New; 5880} 5881 5882void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 5883 AdjustDeclIfTemplate(TagD); 5884 TagDecl *Tag = cast<TagDecl>(TagD); 5885 5886 // Enter the tag context. 5887 PushDeclContext(S, Tag); 5888} 5889 5890void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 5891 SourceLocation LBraceLoc) { 5892 AdjustDeclIfTemplate(TagD); 5893 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 5894 5895 FieldCollector->StartClass(); 5896 5897 if (!Record->getIdentifier()) 5898 return; 5899 5900 // C++ [class]p2: 5901 // [...] The class-name is also inserted into the scope of the 5902 // class itself; this is known as the injected-class-name. For 5903 // purposes of access checking, the injected-class-name is treated 5904 // as if it were a public member name. 5905 CXXRecordDecl *InjectedClassName 5906 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5907 CurContext, Record->getLocation(), 5908 Record->getIdentifier(), 5909 Record->getTagKeywordLoc(), 5910 Record); 5911 InjectedClassName->setImplicit(); 5912 InjectedClassName->setAccess(AS_public); 5913 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5914 InjectedClassName->setDescribedClassTemplate(Template); 5915 PushOnScopeChains(InjectedClassName, S); 5916 assert(InjectedClassName->isInjectedClassName() && 5917 "Broken injected-class-name"); 5918} 5919 5920void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 5921 SourceLocation RBraceLoc) { 5922 AdjustDeclIfTemplate(TagD); 5923 TagDecl *Tag = cast<TagDecl>(TagD); 5924 Tag->setRBraceLoc(RBraceLoc); 5925 5926 if (isa<CXXRecordDecl>(Tag)) 5927 FieldCollector->FinishClass(); 5928 5929 // Exit this scope of this tag's definition. 5930 PopDeclContext(); 5931 5932 // Notify the consumer that we've defined a tag. 5933 Consumer.HandleTagDeclDefinition(Tag); 5934} 5935 5936void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 5937 AdjustDeclIfTemplate(TagD); 5938 TagDecl *Tag = cast<TagDecl>(TagD); 5939 Tag->setInvalidDecl(); 5940 5941 // We're undoing ActOnTagStartDefinition here, not 5942 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5943 // the FieldCollector. 5944 5945 PopDeclContext(); 5946} 5947 5948// Note that FieldName may be null for anonymous bitfields. 5949bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5950 QualType FieldTy, const Expr *BitWidth, 5951 bool *ZeroWidth) { 5952 // Default to true; that shouldn't confuse checks for emptiness 5953 if (ZeroWidth) 5954 *ZeroWidth = true; 5955 5956 // C99 6.7.2.1p4 - verify the field type. 5957 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5958 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5959 // Handle incomplete types with specific error. 5960 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5961 return true; 5962 if (FieldName) 5963 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5964 << FieldName << FieldTy << BitWidth->getSourceRange(); 5965 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5966 << FieldTy << BitWidth->getSourceRange(); 5967 } 5968 5969 // If the bit-width is type- or value-dependent, don't try to check 5970 // it now. 5971 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5972 return false; 5973 5974 llvm::APSInt Value; 5975 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5976 return true; 5977 5978 if (Value != 0 && ZeroWidth) 5979 *ZeroWidth = false; 5980 5981 // Zero-width bitfield is ok for anonymous field. 5982 if (Value == 0 && FieldName) 5983 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5984 5985 if (Value.isSigned() && Value.isNegative()) { 5986 if (FieldName) 5987 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5988 << FieldName << Value.toString(10); 5989 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5990 << Value.toString(10); 5991 } 5992 5993 if (!FieldTy->isDependentType()) { 5994 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5995 if (Value.getZExtValue() > TypeSize) { 5996 if (!getLangOptions().CPlusPlus) { 5997 if (FieldName) 5998 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5999 << FieldName << (unsigned)Value.getZExtValue() 6000 << (unsigned)TypeSize; 6001 6002 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6003 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6004 } 6005 6006 if (FieldName) 6007 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6008 << FieldName << (unsigned)Value.getZExtValue() 6009 << (unsigned)TypeSize; 6010 else 6011 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6012 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6013 } 6014 } 6015 6016 return false; 6017} 6018 6019/// ActOnField - Each field of a struct/union/class is passed into this in order 6020/// to create a FieldDecl object for it. 6021Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6022 SourceLocation DeclStart, 6023 Declarator &D, ExprTy *BitfieldWidth) { 6024 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6025 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6026 AS_public); 6027 return Res; 6028} 6029 6030/// HandleField - Analyze a field of a C struct or a C++ data member. 6031/// 6032FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6033 SourceLocation DeclStart, 6034 Declarator &D, Expr *BitWidth, 6035 AccessSpecifier AS) { 6036 IdentifierInfo *II = D.getIdentifier(); 6037 SourceLocation Loc = DeclStart; 6038 if (II) Loc = D.getIdentifierLoc(); 6039 6040 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6041 QualType T = TInfo->getType(); 6042 if (getLangOptions().CPlusPlus) 6043 CheckExtraCXXDefaultArguments(D); 6044 6045 DiagnoseFunctionSpecifiers(D); 6046 6047 if (D.getDeclSpec().isThreadSpecified()) 6048 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6049 6050 // Check to see if this name was declared as a member previously 6051 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6052 LookupName(Previous, S); 6053 assert((Previous.empty() || Previous.isOverloadedResult() || 6054 Previous.isSingleResult()) 6055 && "Lookup of member name should be either overloaded, single or null"); 6056 6057 // If the name is overloaded then get any declaration else get the single result 6058 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6059 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6060 6061 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6062 // Maybe we will complain about the shadowed template parameter. 6063 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6064 // Just pretend that we didn't see the previous declaration. 6065 PrevDecl = 0; 6066 } 6067 6068 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6069 PrevDecl = 0; 6070 6071 bool Mutable 6072 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6073 SourceLocation TSSL = D.getSourceRange().getBegin(); 6074 FieldDecl *NewFD 6075 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6076 AS, PrevDecl, &D); 6077 6078 if (NewFD->isInvalidDecl()) 6079 Record->setInvalidDecl(); 6080 6081 if (NewFD->isInvalidDecl() && PrevDecl) { 6082 // Don't introduce NewFD into scope; there's already something 6083 // with the same name in the same scope. 6084 } else if (II) { 6085 PushOnScopeChains(NewFD, S); 6086 } else 6087 Record->addDecl(NewFD); 6088 6089 return NewFD; 6090} 6091 6092/// \brief Build a new FieldDecl and check its well-formedness. 6093/// 6094/// This routine builds a new FieldDecl given the fields name, type, 6095/// record, etc. \p PrevDecl should refer to any previous declaration 6096/// with the same name and in the same scope as the field to be 6097/// created. 6098/// 6099/// \returns a new FieldDecl. 6100/// 6101/// \todo The Declarator argument is a hack. It will be removed once 6102FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6103 TypeSourceInfo *TInfo, 6104 RecordDecl *Record, SourceLocation Loc, 6105 bool Mutable, Expr *BitWidth, 6106 SourceLocation TSSL, 6107 AccessSpecifier AS, NamedDecl *PrevDecl, 6108 Declarator *D) { 6109 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6110 bool InvalidDecl = false; 6111 if (D) InvalidDecl = D->isInvalidType(); 6112 6113 // If we receive a broken type, recover by assuming 'int' and 6114 // marking this declaration as invalid. 6115 if (T.isNull()) { 6116 InvalidDecl = true; 6117 T = Context.IntTy; 6118 } 6119 6120 QualType EltTy = Context.getBaseElementType(T); 6121 if (!EltTy->isDependentType() && 6122 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6123 // Fields of incomplete type force their record to be invalid. 6124 Record->setInvalidDecl(); 6125 InvalidDecl = true; 6126 } 6127 6128 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6129 // than a variably modified type. 6130 if (!InvalidDecl && T->isVariablyModifiedType()) { 6131 bool SizeIsNegative; 6132 llvm::APSInt Oversized; 6133 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6134 SizeIsNegative, 6135 Oversized); 6136 if (!FixedTy.isNull()) { 6137 Diag(Loc, diag::warn_illegal_constant_array_size); 6138 T = FixedTy; 6139 } else { 6140 if (SizeIsNegative) 6141 Diag(Loc, diag::err_typecheck_negative_array_size); 6142 else if (Oversized.getBoolValue()) 6143 Diag(Loc, diag::err_array_too_large) 6144 << Oversized.toString(10); 6145 else 6146 Diag(Loc, diag::err_typecheck_field_variable_size); 6147 InvalidDecl = true; 6148 } 6149 } 6150 6151 // Fields can not have abstract class types 6152 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6153 diag::err_abstract_type_in_decl, 6154 AbstractFieldType)) 6155 InvalidDecl = true; 6156 6157 bool ZeroWidth = false; 6158 // If this is declared as a bit-field, check the bit-field. 6159 if (!InvalidDecl && BitWidth && 6160 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6161 InvalidDecl = true; 6162 BitWidth = 0; 6163 ZeroWidth = false; 6164 } 6165 6166 // Check that 'mutable' is consistent with the type of the declaration. 6167 if (!InvalidDecl && Mutable) { 6168 unsigned DiagID = 0; 6169 if (T->isReferenceType()) 6170 DiagID = diag::err_mutable_reference; 6171 else if (T.isConstQualified()) 6172 DiagID = diag::err_mutable_const; 6173 6174 if (DiagID) { 6175 SourceLocation ErrLoc = Loc; 6176 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6177 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6178 Diag(ErrLoc, DiagID); 6179 Mutable = false; 6180 InvalidDecl = true; 6181 } 6182 } 6183 6184 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6185 BitWidth, Mutable); 6186 if (InvalidDecl) 6187 NewFD->setInvalidDecl(); 6188 6189 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6190 Diag(Loc, diag::err_duplicate_member) << II; 6191 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6192 NewFD->setInvalidDecl(); 6193 } 6194 6195 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6196 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 6197 6198 if (!T->isPODType()) 6199 CXXRecord->setPOD(false); 6200 if (!ZeroWidth) 6201 CXXRecord->setEmpty(false); 6202 if (T->isReferenceType()) 6203 CXXRecord->setHasTrivialConstructor(false); 6204 6205 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6206 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6207 if (RDecl->getDefinition()) { 6208 if (!RDecl->hasTrivialConstructor()) 6209 CXXRecord->setHasTrivialConstructor(false); 6210 if (!RDecl->hasTrivialCopyConstructor()) 6211 CXXRecord->setHasTrivialCopyConstructor(false); 6212 if (!RDecl->hasTrivialCopyAssignment()) 6213 CXXRecord->setHasTrivialCopyAssignment(false); 6214 if (!RDecl->hasTrivialDestructor()) 6215 CXXRecord->setHasTrivialDestructor(false); 6216 6217 // C++ 9.5p1: An object of a class with a non-trivial 6218 // constructor, a non-trivial copy constructor, a non-trivial 6219 // destructor, or a non-trivial copy assignment operator 6220 // cannot be a member of a union, nor can an array of such 6221 // objects. 6222 // TODO: C++0x alters this restriction significantly. 6223 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6224 NewFD->setInvalidDecl(); 6225 } 6226 } 6227 } 6228 6229 // FIXME: We need to pass in the attributes given an AST 6230 // representation, not a parser representation. 6231 if (D) 6232 // FIXME: What to pass instead of TUScope? 6233 ProcessDeclAttributes(TUScope, NewFD, *D); 6234 6235 if (T.isObjCGCWeak()) 6236 Diag(Loc, diag::warn_attribute_weak_on_field); 6237 6238 NewFD->setAccess(AS); 6239 6240 // C++ [dcl.init.aggr]p1: 6241 // An aggregate is an array or a class (clause 9) with [...] no 6242 // private or protected non-static data members (clause 11). 6243 // A POD must be an aggregate. 6244 if (getLangOptions().CPlusPlus && 6245 (AS == AS_private || AS == AS_protected)) { 6246 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 6247 CXXRecord->setAggregate(false); 6248 CXXRecord->setPOD(false); 6249 } 6250 6251 return NewFD; 6252} 6253 6254bool Sema::CheckNontrivialField(FieldDecl *FD) { 6255 assert(FD); 6256 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6257 6258 if (FD->isInvalidDecl()) 6259 return true; 6260 6261 QualType EltTy = Context.getBaseElementType(FD->getType()); 6262 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6263 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6264 if (RDecl->getDefinition()) { 6265 // We check for copy constructors before constructors 6266 // because otherwise we'll never get complaints about 6267 // copy constructors. 6268 6269 CXXSpecialMember member = CXXInvalid; 6270 if (!RDecl->hasTrivialCopyConstructor()) 6271 member = CXXCopyConstructor; 6272 else if (!RDecl->hasTrivialConstructor()) 6273 member = CXXConstructor; 6274 else if (!RDecl->hasTrivialCopyAssignment()) 6275 member = CXXCopyAssignment; 6276 else if (!RDecl->hasTrivialDestructor()) 6277 member = CXXDestructor; 6278 6279 if (member != CXXInvalid) { 6280 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6281 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6282 DiagnoseNontrivial(RT, member); 6283 return true; 6284 } 6285 } 6286 } 6287 6288 return false; 6289} 6290 6291/// DiagnoseNontrivial - Given that a class has a non-trivial 6292/// special member, figure out why. 6293void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6294 QualType QT(T, 0U); 6295 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6296 6297 // Check whether the member was user-declared. 6298 switch (member) { 6299 case CXXInvalid: 6300 break; 6301 6302 case CXXConstructor: 6303 if (RD->hasUserDeclaredConstructor()) { 6304 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6305 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6306 const FunctionDecl *body = 0; 6307 ci->hasBody(body); 6308 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6309 SourceLocation CtorLoc = ci->getLocation(); 6310 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6311 return; 6312 } 6313 } 6314 6315 assert(0 && "found no user-declared constructors"); 6316 return; 6317 } 6318 break; 6319 6320 case CXXCopyConstructor: 6321 if (RD->hasUserDeclaredCopyConstructor()) { 6322 SourceLocation CtorLoc = 6323 RD->getCopyConstructor(Context, 0)->getLocation(); 6324 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6325 return; 6326 } 6327 break; 6328 6329 case CXXCopyAssignment: 6330 if (RD->hasUserDeclaredCopyAssignment()) { 6331 // FIXME: this should use the location of the copy 6332 // assignment, not the type. 6333 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6334 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6335 return; 6336 } 6337 break; 6338 6339 case CXXDestructor: 6340 if (RD->hasUserDeclaredDestructor()) { 6341 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6342 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6343 return; 6344 } 6345 break; 6346 } 6347 6348 typedef CXXRecordDecl::base_class_iterator base_iter; 6349 6350 // Virtual bases and members inhibit trivial copying/construction, 6351 // but not trivial destruction. 6352 if (member != CXXDestructor) { 6353 // Check for virtual bases. vbases includes indirect virtual bases, 6354 // so we just iterate through the direct bases. 6355 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6356 if (bi->isVirtual()) { 6357 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6358 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6359 return; 6360 } 6361 6362 // Check for virtual methods. 6363 typedef CXXRecordDecl::method_iterator meth_iter; 6364 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6365 ++mi) { 6366 if (mi->isVirtual()) { 6367 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6368 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6369 return; 6370 } 6371 } 6372 } 6373 6374 bool (CXXRecordDecl::*hasTrivial)() const; 6375 switch (member) { 6376 case CXXConstructor: 6377 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6378 case CXXCopyConstructor: 6379 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6380 case CXXCopyAssignment: 6381 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6382 case CXXDestructor: 6383 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6384 default: 6385 assert(0 && "unexpected special member"); return; 6386 } 6387 6388 // Check for nontrivial bases (and recurse). 6389 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6390 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6391 assert(BaseRT && "Don't know how to handle dependent bases"); 6392 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6393 if (!(BaseRecTy->*hasTrivial)()) { 6394 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6395 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6396 DiagnoseNontrivial(BaseRT, member); 6397 return; 6398 } 6399 } 6400 6401 // Check for nontrivial members (and recurse). 6402 typedef RecordDecl::field_iterator field_iter; 6403 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6404 ++fi) { 6405 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6406 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6407 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6408 6409 if (!(EltRD->*hasTrivial)()) { 6410 SourceLocation FLoc = (*fi)->getLocation(); 6411 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6412 DiagnoseNontrivial(EltRT, member); 6413 return; 6414 } 6415 } 6416 } 6417 6418 assert(0 && "found no explanation for non-trivial member"); 6419} 6420 6421/// TranslateIvarVisibility - Translate visibility from a token ID to an 6422/// AST enum value. 6423static ObjCIvarDecl::AccessControl 6424TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6425 switch (ivarVisibility) { 6426 default: assert(0 && "Unknown visitibility kind"); 6427 case tok::objc_private: return ObjCIvarDecl::Private; 6428 case tok::objc_public: return ObjCIvarDecl::Public; 6429 case tok::objc_protected: return ObjCIvarDecl::Protected; 6430 case tok::objc_package: return ObjCIvarDecl::Package; 6431 } 6432} 6433 6434/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6435/// in order to create an IvarDecl object for it. 6436Decl *Sema::ActOnIvar(Scope *S, 6437 SourceLocation DeclStart, 6438 Decl *IntfDecl, 6439 Declarator &D, ExprTy *BitfieldWidth, 6440 tok::ObjCKeywordKind Visibility) { 6441 6442 IdentifierInfo *II = D.getIdentifier(); 6443 Expr *BitWidth = (Expr*)BitfieldWidth; 6444 SourceLocation Loc = DeclStart; 6445 if (II) Loc = D.getIdentifierLoc(); 6446 6447 // FIXME: Unnamed fields can be handled in various different ways, for 6448 // example, unnamed unions inject all members into the struct namespace! 6449 6450 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6451 QualType T = TInfo->getType(); 6452 6453 if (BitWidth) { 6454 // 6.7.2.1p3, 6.7.2.1p4 6455 if (VerifyBitField(Loc, II, T, BitWidth)) { 6456 D.setInvalidType(); 6457 BitWidth = 0; 6458 } 6459 } else { 6460 // Not a bitfield. 6461 6462 // validate II. 6463 6464 } 6465 if (T->isReferenceType()) { 6466 Diag(Loc, diag::err_ivar_reference_type); 6467 D.setInvalidType(); 6468 } 6469 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6470 // than a variably modified type. 6471 else if (T->isVariablyModifiedType()) { 6472 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6473 D.setInvalidType(); 6474 } 6475 6476 // Get the visibility (access control) for this ivar. 6477 ObjCIvarDecl::AccessControl ac = 6478 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6479 : ObjCIvarDecl::None; 6480 // Must set ivar's DeclContext to its enclosing interface. 6481 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6482 ObjCContainerDecl *EnclosingContext; 6483 if (ObjCImplementationDecl *IMPDecl = 6484 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6485 if (!LangOpts.ObjCNonFragileABI2) { 6486 // Case of ivar declared in an implementation. Context is that of its class. 6487 EnclosingContext = IMPDecl->getClassInterface(); 6488 assert(EnclosingContext && "Implementation has no class interface!"); 6489 } 6490 else 6491 EnclosingContext = EnclosingDecl; 6492 } else { 6493 if (ObjCCategoryDecl *CDecl = 6494 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6495 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6496 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6497 return 0; 6498 } 6499 } 6500 EnclosingContext = EnclosingDecl; 6501 } 6502 6503 // Construct the decl. 6504 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6505 EnclosingContext, Loc, II, T, 6506 TInfo, ac, (Expr *)BitfieldWidth); 6507 6508 if (II) { 6509 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6510 ForRedeclaration); 6511 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6512 && !isa<TagDecl>(PrevDecl)) { 6513 Diag(Loc, diag::err_duplicate_member) << II; 6514 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6515 NewID->setInvalidDecl(); 6516 } 6517 } 6518 6519 // Process attributes attached to the ivar. 6520 ProcessDeclAttributes(S, NewID, D); 6521 6522 if (D.isInvalidType()) 6523 NewID->setInvalidDecl(); 6524 6525 if (II) { 6526 // FIXME: When interfaces are DeclContexts, we'll need to add 6527 // these to the interface. 6528 S->AddDecl(NewID); 6529 IdResolver.AddDecl(NewID); 6530 } 6531 6532 return NewID; 6533} 6534 6535/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6536/// class and class extensions. For every class @interface and class 6537/// extension @interface, if the last ivar is a bitfield of any type, 6538/// then add an implicit `char :0` ivar to the end of that interface. 6539void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6540 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6541 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6542 return; 6543 6544 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6545 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6546 6547 if (!Ivar->isBitField()) 6548 return; 6549 uint64_t BitFieldSize = 6550 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6551 if (BitFieldSize == 0) 6552 return; 6553 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6554 if (!ID) { 6555 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6556 if (!CD->IsClassExtension()) 6557 return; 6558 } 6559 // No need to add this to end of @implementation. 6560 else 6561 return; 6562 } 6563 // All conditions are met. Add a new bitfield to the tail end of ivars. 6564 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6565 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 6566 6567 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6568 DeclLoc, 0, 6569 Context.CharTy, 6570 Context.CreateTypeSourceInfo(Context.CharTy), 6571 ObjCIvarDecl::Private, BW, 6572 true); 6573 AllIvarDecls.push_back(Ivar); 6574} 6575 6576void Sema::ActOnFields(Scope* S, 6577 SourceLocation RecLoc, Decl *EnclosingDecl, 6578 Decl **Fields, unsigned NumFields, 6579 SourceLocation LBrac, SourceLocation RBrac, 6580 AttributeList *Attr) { 6581 assert(EnclosingDecl && "missing record or interface decl"); 6582 6583 // If the decl this is being inserted into is invalid, then it may be a 6584 // redeclaration or some other bogus case. Don't try to add fields to it. 6585 if (EnclosingDecl->isInvalidDecl()) { 6586 // FIXME: Deallocate fields? 6587 return; 6588 } 6589 6590 6591 // Verify that all the fields are okay. 6592 unsigned NumNamedMembers = 0; 6593 llvm::SmallVector<FieldDecl*, 32> RecFields; 6594 6595 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6596 for (unsigned i = 0; i != NumFields; ++i) { 6597 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6598 6599 // Get the type for the field. 6600 Type *FDTy = FD->getType().getTypePtr(); 6601 6602 if (!FD->isAnonymousStructOrUnion()) { 6603 // Remember all fields written by the user. 6604 RecFields.push_back(FD); 6605 } 6606 6607 // If the field is already invalid for some reason, don't emit more 6608 // diagnostics about it. 6609 if (FD->isInvalidDecl()) { 6610 EnclosingDecl->setInvalidDecl(); 6611 continue; 6612 } 6613 6614 // C99 6.7.2.1p2: 6615 // A structure or union shall not contain a member with 6616 // incomplete or function type (hence, a structure shall not 6617 // contain an instance of itself, but may contain a pointer to 6618 // an instance of itself), except that the last member of a 6619 // structure with more than one named member may have incomplete 6620 // array type; such a structure (and any union containing, 6621 // possibly recursively, a member that is such a structure) 6622 // shall not be a member of a structure or an element of an 6623 // array. 6624 if (FDTy->isFunctionType()) { 6625 // Field declared as a function. 6626 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6627 << FD->getDeclName(); 6628 FD->setInvalidDecl(); 6629 EnclosingDecl->setInvalidDecl(); 6630 continue; 6631 } else if (FDTy->isIncompleteArrayType() && Record && 6632 ((i == NumFields - 1 && !Record->isUnion()) || 6633 (getLangOptions().Microsoft && 6634 (i == NumFields - 1 || Record->isUnion())))) { 6635 // Flexible array member. 6636 // Microsoft is more permissive regarding flexible array. 6637 // It will accept flexible array in union and also 6638 // as the sole element of a struct/class. 6639 if (getLangOptions().Microsoft) { 6640 if (Record->isUnion()) 6641 Diag(FD->getLocation(), diag::ext_flexible_array_union) 6642 << FD->getDeclName(); 6643 else if (NumFields == 1) 6644 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 6645 << FD->getDeclName() << Record->getTagKind(); 6646 } else if (NumNamedMembers < 1) { 6647 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6648 << FD->getDeclName(); 6649 FD->setInvalidDecl(); 6650 EnclosingDecl->setInvalidDecl(); 6651 continue; 6652 } 6653 if (!FD->getType()->isDependentType() && 6654 !Context.getBaseElementType(FD->getType())->isPODType()) { 6655 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6656 << FD->getDeclName() << FD->getType(); 6657 FD->setInvalidDecl(); 6658 EnclosingDecl->setInvalidDecl(); 6659 continue; 6660 } 6661 // Okay, we have a legal flexible array member at the end of the struct. 6662 if (Record) 6663 Record->setHasFlexibleArrayMember(true); 6664 } else if (!FDTy->isDependentType() && 6665 RequireCompleteType(FD->getLocation(), FD->getType(), 6666 diag::err_field_incomplete)) { 6667 // Incomplete type 6668 FD->setInvalidDecl(); 6669 EnclosingDecl->setInvalidDecl(); 6670 continue; 6671 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6672 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6673 // If this is a member of a union, then entire union becomes "flexible". 6674 if (Record && Record->isUnion()) { 6675 Record->setHasFlexibleArrayMember(true); 6676 } else { 6677 // If this is a struct/class and this is not the last element, reject 6678 // it. Note that GCC supports variable sized arrays in the middle of 6679 // structures. 6680 if (i != NumFields-1) 6681 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6682 << FD->getDeclName() << FD->getType(); 6683 else { 6684 // We support flexible arrays at the end of structs in 6685 // other structs as an extension. 6686 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6687 << FD->getDeclName(); 6688 if (Record) 6689 Record->setHasFlexibleArrayMember(true); 6690 } 6691 } 6692 } 6693 if (Record && FDTTy->getDecl()->hasObjectMember()) 6694 Record->setHasObjectMember(true); 6695 } else if (FDTy->isObjCObjectType()) { 6696 /// A field cannot be an Objective-c object 6697 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6698 FD->setInvalidDecl(); 6699 EnclosingDecl->setInvalidDecl(); 6700 continue; 6701 } else if (getLangOptions().ObjC1 && 6702 getLangOptions().getGCMode() != LangOptions::NonGC && 6703 Record && 6704 (FD->getType()->isObjCObjectPointerType() || 6705 FD->getType().isObjCGCStrong())) 6706 Record->setHasObjectMember(true); 6707 else if (Context.getAsArrayType(FD->getType())) { 6708 QualType BaseType = Context.getBaseElementType(FD->getType()); 6709 if (Record && BaseType->isRecordType() && 6710 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6711 Record->setHasObjectMember(true); 6712 } 6713 // Keep track of the number of named members. 6714 if (FD->getIdentifier()) 6715 ++NumNamedMembers; 6716 } 6717 6718 // Okay, we successfully defined 'Record'. 6719 if (Record) { 6720 Record->completeDefinition(); 6721 } else { 6722 ObjCIvarDecl **ClsFields = 6723 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6724 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6725 ID->setLocEnd(RBrac); 6726 // Add ivar's to class's DeclContext. 6727 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6728 ClsFields[i]->setLexicalDeclContext(ID); 6729 ID->addDecl(ClsFields[i]); 6730 } 6731 // Must enforce the rule that ivars in the base classes may not be 6732 // duplicates. 6733 if (ID->getSuperClass()) 6734 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6735 } else if (ObjCImplementationDecl *IMPDecl = 6736 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6737 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6738 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6739 // Ivar declared in @implementation never belongs to the implementation. 6740 // Only it is in implementation's lexical context. 6741 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6742 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6743 } else if (ObjCCategoryDecl *CDecl = 6744 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6745 // case of ivars in class extension; all other cases have been 6746 // reported as errors elsewhere. 6747 // FIXME. Class extension does not have a LocEnd field. 6748 // CDecl->setLocEnd(RBrac); 6749 // Add ivar's to class extension's DeclContext. 6750 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6751 ClsFields[i]->setLexicalDeclContext(CDecl); 6752 CDecl->addDecl(ClsFields[i]); 6753 } 6754 } 6755 } 6756 6757 if (Attr) 6758 ProcessDeclAttributeList(S, Record, Attr); 6759 6760 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6761 // set the visibility of this record. 6762 if (Record && !Record->getDeclContext()->isRecord()) 6763 AddPushedVisibilityAttribute(Record); 6764} 6765 6766/// \brief Determine whether the given integral value is representable within 6767/// the given type T. 6768static bool isRepresentableIntegerValue(ASTContext &Context, 6769 llvm::APSInt &Value, 6770 QualType T) { 6771 assert(T->isIntegralType(Context) && "Integral type required!"); 6772 unsigned BitWidth = Context.getIntWidth(T); 6773 6774 if (Value.isUnsigned() || Value.isNonNegative()) 6775 return Value.getActiveBits() < BitWidth; 6776 6777 return Value.getMinSignedBits() <= BitWidth; 6778} 6779 6780// \brief Given an integral type, return the next larger integral type 6781// (or a NULL type of no such type exists). 6782static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6783 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6784 // enum checking below. 6785 assert(T->isIntegralType(Context) && "Integral type required!"); 6786 const unsigned NumTypes = 4; 6787 QualType SignedIntegralTypes[NumTypes] = { 6788 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6789 }; 6790 QualType UnsignedIntegralTypes[NumTypes] = { 6791 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6792 Context.UnsignedLongLongTy 6793 }; 6794 6795 unsigned BitWidth = Context.getTypeSize(T); 6796 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6797 : UnsignedIntegralTypes; 6798 for (unsigned I = 0; I != NumTypes; ++I) 6799 if (Context.getTypeSize(Types[I]) > BitWidth) 6800 return Types[I]; 6801 6802 return QualType(); 6803} 6804 6805EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6806 EnumConstantDecl *LastEnumConst, 6807 SourceLocation IdLoc, 6808 IdentifierInfo *Id, 6809 Expr *Val) { 6810 unsigned IntWidth = Context.Target.getIntWidth(); 6811 llvm::APSInt EnumVal(IntWidth); 6812 QualType EltTy; 6813 if (Val) { 6814 if (Enum->isDependentType() || Val->isTypeDependent()) 6815 EltTy = Context.DependentTy; 6816 else { 6817 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6818 SourceLocation ExpLoc; 6819 if (!Val->isValueDependent() && 6820 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6821 Val = 0; 6822 } else { 6823 if (!getLangOptions().CPlusPlus) { 6824 // C99 6.7.2.2p2: 6825 // The expression that defines the value of an enumeration constant 6826 // shall be an integer constant expression that has a value 6827 // representable as an int. 6828 6829 // Complain if the value is not representable in an int. 6830 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6831 Diag(IdLoc, diag::ext_enum_value_not_int) 6832 << EnumVal.toString(10) << Val->getSourceRange() 6833 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6834 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6835 // Force the type of the expression to 'int'. 6836 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 6837 } 6838 } 6839 6840 // C++0x [dcl.enum]p5: 6841 // If the underlying type is not fixed, the type of each enumerator 6842 // is the type of its initializing value: 6843 // - If an initializer is specified for an enumerator, the 6844 // initializing value has the same type as the expression. 6845 EltTy = Val->getType(); 6846 } 6847 } 6848 } 6849 6850 if (!Val) { 6851 if (Enum->isDependentType()) 6852 EltTy = Context.DependentTy; 6853 else if (!LastEnumConst) { 6854 // C++0x [dcl.enum]p5: 6855 // If the underlying type is not fixed, the type of each enumerator 6856 // is the type of its initializing value: 6857 // - If no initializer is specified for the first enumerator, the 6858 // initializing value has an unspecified integral type. 6859 // 6860 // GCC uses 'int' for its unspecified integral type, as does 6861 // C99 6.7.2.2p3. 6862 EltTy = Context.IntTy; 6863 } else { 6864 // Assign the last value + 1. 6865 EnumVal = LastEnumConst->getInitVal(); 6866 ++EnumVal; 6867 EltTy = LastEnumConst->getType(); 6868 6869 // Check for overflow on increment. 6870 if (EnumVal < LastEnumConst->getInitVal()) { 6871 // C++0x [dcl.enum]p5: 6872 // If the underlying type is not fixed, the type of each enumerator 6873 // is the type of its initializing value: 6874 // 6875 // - Otherwise the type of the initializing value is the same as 6876 // the type of the initializing value of the preceding enumerator 6877 // unless the incremented value is not representable in that type, 6878 // in which case the type is an unspecified integral type 6879 // sufficient to contain the incremented value. If no such type 6880 // exists, the program is ill-formed. 6881 QualType T = getNextLargerIntegralType(Context, EltTy); 6882 if (T.isNull()) { 6883 // There is no integral type larger enough to represent this 6884 // value. Complain, then allow the value to wrap around. 6885 EnumVal = LastEnumConst->getInitVal(); 6886 EnumVal.zext(EnumVal.getBitWidth() * 2); 6887 Diag(IdLoc, diag::warn_enumerator_too_large) 6888 << EnumVal.toString(10); 6889 } else { 6890 EltTy = T; 6891 } 6892 6893 // Retrieve the last enumerator's value, extent that type to the 6894 // type that is supposed to be large enough to represent the incremented 6895 // value, then increment. 6896 EnumVal = LastEnumConst->getInitVal(); 6897 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6898 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6899 ++EnumVal; 6900 6901 // If we're not in C++, diagnose the overflow of enumerator values, 6902 // which in C99 means that the enumerator value is not representable in 6903 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6904 // permits enumerator values that are representable in some larger 6905 // integral type. 6906 if (!getLangOptions().CPlusPlus && !T.isNull()) 6907 Diag(IdLoc, diag::warn_enum_value_overflow); 6908 } else if (!getLangOptions().CPlusPlus && 6909 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6910 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6911 Diag(IdLoc, diag::ext_enum_value_not_int) 6912 << EnumVal.toString(10) << 1; 6913 } 6914 } 6915 } 6916 6917 if (!EltTy->isDependentType()) { 6918 // Make the enumerator value match the signedness and size of the 6919 // enumerator's type. 6920 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6921 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6922 } 6923 6924 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6925 Val, EnumVal); 6926} 6927 6928 6929Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 6930 Decl *lastEnumConst, 6931 SourceLocation IdLoc, 6932 IdentifierInfo *Id, 6933 SourceLocation EqualLoc, ExprTy *val) { 6934 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 6935 EnumConstantDecl *LastEnumConst = 6936 cast_or_null<EnumConstantDecl>(lastEnumConst); 6937 Expr *Val = static_cast<Expr*>(val); 6938 6939 // The scope passed in may not be a decl scope. Zip up the scope tree until 6940 // we find one that is. 6941 S = getNonFieldDeclScope(S); 6942 6943 // Verify that there isn't already something declared with this name in this 6944 // scope. 6945 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6946 ForRedeclaration); 6947 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6948 // Maybe we will complain about the shadowed template parameter. 6949 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6950 // Just pretend that we didn't see the previous declaration. 6951 PrevDecl = 0; 6952 } 6953 6954 if (PrevDecl) { 6955 // When in C++, we may get a TagDecl with the same name; in this case the 6956 // enum constant will 'hide' the tag. 6957 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6958 "Received TagDecl when not in C++!"); 6959 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6960 if (isa<EnumConstantDecl>(PrevDecl)) 6961 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6962 else 6963 Diag(IdLoc, diag::err_redefinition) << Id; 6964 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6965 return 0; 6966 } 6967 } 6968 6969 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6970 IdLoc, Id, Val); 6971 6972 // Register this decl in the current scope stack. 6973 if (New) { 6974 New->setAccess(TheEnumDecl->getAccess()); 6975 PushOnScopeChains(New, S); 6976 } 6977 6978 return New; 6979} 6980 6981void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6982 SourceLocation RBraceLoc, Decl *EnumDeclX, 6983 Decl **Elements, unsigned NumElements, 6984 Scope *S, AttributeList *Attr) { 6985 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 6986 QualType EnumType = Context.getTypeDeclType(Enum); 6987 6988 if (Attr) 6989 ProcessDeclAttributeList(S, Enum, Attr); 6990 6991 if (Enum->isDependentType()) { 6992 for (unsigned i = 0; i != NumElements; ++i) { 6993 EnumConstantDecl *ECD = 6994 cast_or_null<EnumConstantDecl>(Elements[i]); 6995 if (!ECD) continue; 6996 6997 ECD->setType(EnumType); 6998 } 6999 7000 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7001 return; 7002 } 7003 7004 // TODO: If the result value doesn't fit in an int, it must be a long or long 7005 // long value. ISO C does not support this, but GCC does as an extension, 7006 // emit a warning. 7007 unsigned IntWidth = Context.Target.getIntWidth(); 7008 unsigned CharWidth = Context.Target.getCharWidth(); 7009 unsigned ShortWidth = Context.Target.getShortWidth(); 7010 7011 // Verify that all the values are okay, compute the size of the values, and 7012 // reverse the list. 7013 unsigned NumNegativeBits = 0; 7014 unsigned NumPositiveBits = 0; 7015 7016 // Keep track of whether all elements have type int. 7017 bool AllElementsInt = true; 7018 7019 for (unsigned i = 0; i != NumElements; ++i) { 7020 EnumConstantDecl *ECD = 7021 cast_or_null<EnumConstantDecl>(Elements[i]); 7022 if (!ECD) continue; // Already issued a diagnostic. 7023 7024 const llvm::APSInt &InitVal = ECD->getInitVal(); 7025 7026 // Keep track of the size of positive and negative values. 7027 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7028 NumPositiveBits = std::max(NumPositiveBits, 7029 (unsigned)InitVal.getActiveBits()); 7030 else 7031 NumNegativeBits = std::max(NumNegativeBits, 7032 (unsigned)InitVal.getMinSignedBits()); 7033 7034 // Keep track of whether every enum element has type int (very commmon). 7035 if (AllElementsInt) 7036 AllElementsInt = ECD->getType() == Context.IntTy; 7037 } 7038 7039 // Figure out the type that should be used for this enum. 7040 // FIXME: Support -fshort-enums. 7041 QualType BestType; 7042 unsigned BestWidth; 7043 7044 // C++0x N3000 [conv.prom]p3: 7045 // An rvalue of an unscoped enumeration type whose underlying 7046 // type is not fixed can be converted to an rvalue of the first 7047 // of the following types that can represent all the values of 7048 // the enumeration: int, unsigned int, long int, unsigned long 7049 // int, long long int, or unsigned long long int. 7050 // C99 6.4.4.3p2: 7051 // An identifier declared as an enumeration constant has type int. 7052 // The C99 rule is modified by a gcc extension 7053 QualType BestPromotionType; 7054 7055 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7056 7057 if (NumNegativeBits) { 7058 // If there is a negative value, figure out the smallest integer type (of 7059 // int/long/longlong) that fits. 7060 // If it's packed, check also if it fits a char or a short. 7061 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7062 BestType = Context.SignedCharTy; 7063 BestWidth = CharWidth; 7064 } else if (Packed && NumNegativeBits <= ShortWidth && 7065 NumPositiveBits < ShortWidth) { 7066 BestType = Context.ShortTy; 7067 BestWidth = ShortWidth; 7068 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7069 BestType = Context.IntTy; 7070 BestWidth = IntWidth; 7071 } else { 7072 BestWidth = Context.Target.getLongWidth(); 7073 7074 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7075 BestType = Context.LongTy; 7076 } else { 7077 BestWidth = Context.Target.getLongLongWidth(); 7078 7079 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7080 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7081 BestType = Context.LongLongTy; 7082 } 7083 } 7084 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7085 } else { 7086 // If there is no negative value, figure out the smallest type that fits 7087 // all of the enumerator values. 7088 // If it's packed, check also if it fits a char or a short. 7089 if (Packed && NumPositiveBits <= CharWidth) { 7090 BestType = Context.UnsignedCharTy; 7091 BestPromotionType = Context.IntTy; 7092 BestWidth = CharWidth; 7093 } else if (Packed && NumPositiveBits <= ShortWidth) { 7094 BestType = Context.UnsignedShortTy; 7095 BestPromotionType = Context.IntTy; 7096 BestWidth = ShortWidth; 7097 } else if (NumPositiveBits <= IntWidth) { 7098 BestType = Context.UnsignedIntTy; 7099 BestWidth = IntWidth; 7100 BestPromotionType 7101 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7102 ? Context.UnsignedIntTy : Context.IntTy; 7103 } else if (NumPositiveBits <= 7104 (BestWidth = Context.Target.getLongWidth())) { 7105 BestType = Context.UnsignedLongTy; 7106 BestPromotionType 7107 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7108 ? Context.UnsignedLongTy : Context.LongTy; 7109 } else { 7110 BestWidth = Context.Target.getLongLongWidth(); 7111 assert(NumPositiveBits <= BestWidth && 7112 "How could an initializer get larger than ULL?"); 7113 BestType = Context.UnsignedLongLongTy; 7114 BestPromotionType 7115 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7116 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7117 } 7118 } 7119 7120 // Loop over all of the enumerator constants, changing their types to match 7121 // the type of the enum if needed. 7122 for (unsigned i = 0; i != NumElements; ++i) { 7123 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7124 if (!ECD) continue; // Already issued a diagnostic. 7125 7126 // Standard C says the enumerators have int type, but we allow, as an 7127 // extension, the enumerators to be larger than int size. If each 7128 // enumerator value fits in an int, type it as an int, otherwise type it the 7129 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7130 // that X has type 'int', not 'unsigned'. 7131 7132 // Determine whether the value fits into an int. 7133 llvm::APSInt InitVal = ECD->getInitVal(); 7134 7135 // If it fits into an integer type, force it. Otherwise force it to match 7136 // the enum decl type. 7137 QualType NewTy; 7138 unsigned NewWidth; 7139 bool NewSign; 7140 if (!getLangOptions().CPlusPlus && 7141 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7142 NewTy = Context.IntTy; 7143 NewWidth = IntWidth; 7144 NewSign = true; 7145 } else if (ECD->getType() == BestType) { 7146 // Already the right type! 7147 if (getLangOptions().CPlusPlus) 7148 // C++ [dcl.enum]p4: Following the closing brace of an 7149 // enum-specifier, each enumerator has the type of its 7150 // enumeration. 7151 ECD->setType(EnumType); 7152 continue; 7153 } else { 7154 NewTy = BestType; 7155 NewWidth = BestWidth; 7156 NewSign = BestType->isSignedIntegerType(); 7157 } 7158 7159 // Adjust the APSInt value. 7160 InitVal.extOrTrunc(NewWidth); 7161 InitVal.setIsSigned(NewSign); 7162 ECD->setInitVal(InitVal); 7163 7164 // Adjust the Expr initializer and type. 7165 if (ECD->getInitExpr()) 7166 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7167 CK_IntegralCast, 7168 ECD->getInitExpr(), 7169 /*base paths*/ 0, 7170 VK_RValue)); 7171 if (getLangOptions().CPlusPlus) 7172 // C++ [dcl.enum]p4: Following the closing brace of an 7173 // enum-specifier, each enumerator has the type of its 7174 // enumeration. 7175 ECD->setType(EnumType); 7176 else 7177 ECD->setType(NewTy); 7178 } 7179 7180 Enum->completeDefinition(BestType, BestPromotionType, 7181 NumPositiveBits, NumNegativeBits); 7182} 7183 7184Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7185 StringLiteral *AsmString = cast<StringLiteral>(expr); 7186 7187 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7188 Loc, AsmString); 7189 CurContext->addDecl(New); 7190 return New; 7191} 7192 7193void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7194 SourceLocation PragmaLoc, 7195 SourceLocation NameLoc) { 7196 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7197 7198 if (PrevDecl) { 7199 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7200 } else { 7201 (void)WeakUndeclaredIdentifiers.insert( 7202 std::pair<IdentifierInfo*,WeakInfo> 7203 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7204 } 7205} 7206 7207void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7208 IdentifierInfo* AliasName, 7209 SourceLocation PragmaLoc, 7210 SourceLocation NameLoc, 7211 SourceLocation AliasNameLoc) { 7212 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7213 LookupOrdinaryName); 7214 WeakInfo W = WeakInfo(Name, NameLoc); 7215 7216 if (PrevDecl) { 7217 if (!PrevDecl->hasAttr<AliasAttr>()) 7218 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7219 DeclApplyPragmaWeak(TUScope, ND, W); 7220 } else { 7221 (void)WeakUndeclaredIdentifiers.insert( 7222 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7223 } 7224} 7225