SemaDecl.cpp revision be04b6df363f083f51636efcf4a8be4c5e8ea038
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} 773 774/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 775/// file scope. lazily create a decl for it. ForRedeclaration is true 776/// if we're creating this built-in in anticipation of redeclaring the 777/// built-in. 778NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 779 Scope *S, bool ForRedeclaration, 780 SourceLocation Loc) { 781 Builtin::ID BID = (Builtin::ID)bid; 782 783 ASTContext::GetBuiltinTypeError Error; 784 QualType R = Context.GetBuiltinType(BID, Error); 785 switch (Error) { 786 case ASTContext::GE_None: 787 // Okay 788 break; 789 790 case ASTContext::GE_Missing_stdio: 791 if (ForRedeclaration) 792 Diag(Loc, diag::err_implicit_decl_requires_stdio) 793 << Context.BuiltinInfo.GetName(BID); 794 return 0; 795 796 case ASTContext::GE_Missing_setjmp: 797 if (ForRedeclaration) 798 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 799 << Context.BuiltinInfo.GetName(BID); 800 return 0; 801 } 802 803 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 804 Diag(Loc, diag::ext_implicit_lib_function_decl) 805 << Context.BuiltinInfo.GetName(BID) 806 << R; 807 if (Context.BuiltinInfo.getHeaderName(BID) && 808 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 809 != Diagnostic::Ignored) 810 Diag(Loc, diag::note_please_include_header) 811 << Context.BuiltinInfo.getHeaderName(BID) 812 << Context.BuiltinInfo.GetName(BID); 813 } 814 815 FunctionDecl *New = FunctionDecl::Create(Context, 816 Context.getTranslationUnitDecl(), 817 Loc, II, R, /*TInfo=*/0, 818 SC_Extern, 819 SC_None, false, 820 /*hasPrototype=*/true); 821 New->setImplicit(); 822 823 // Create Decl objects for each parameter, adding them to the 824 // FunctionDecl. 825 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 826 llvm::SmallVector<ParmVarDecl*, 16> Params; 827 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 828 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 829 FT->getArgType(i), /*TInfo=*/0, 830 SC_None, SC_None, 0)); 831 New->setParams(Params.data(), Params.size()); 832 } 833 834 AddKnownFunctionAttributes(New); 835 836 // TUScope is the translation-unit scope to insert this function into. 837 // FIXME: This is hideous. We need to teach PushOnScopeChains to 838 // relate Scopes to DeclContexts, and probably eliminate CurContext 839 // entirely, but we're not there yet. 840 DeclContext *SavedContext = CurContext; 841 CurContext = Context.getTranslationUnitDecl(); 842 PushOnScopeChains(New, TUScope); 843 CurContext = SavedContext; 844 return New; 845} 846 847/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 848/// same name and scope as a previous declaration 'Old'. Figure out 849/// how to resolve this situation, merging decls or emitting 850/// diagnostics as appropriate. If there was an error, set New to be invalid. 851/// 852void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 853 // If the new decl is known invalid already, don't bother doing any 854 // merging checks. 855 if (New->isInvalidDecl()) return; 856 857 // Allow multiple definitions for ObjC built-in typedefs. 858 // FIXME: Verify the underlying types are equivalent! 859 if (getLangOptions().ObjC1) { 860 const IdentifierInfo *TypeID = New->getIdentifier(); 861 switch (TypeID->getLength()) { 862 default: break; 863 case 2: 864 if (!TypeID->isStr("id")) 865 break; 866 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 867 // Install the built-in type for 'id', ignoring the current definition. 868 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 869 return; 870 case 5: 871 if (!TypeID->isStr("Class")) 872 break; 873 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 874 // Install the built-in type for 'Class', ignoring the current definition. 875 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 876 return; 877 case 3: 878 if (!TypeID->isStr("SEL")) 879 break; 880 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 881 // Install the built-in type for 'SEL', ignoring the current definition. 882 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 883 return; 884 case 8: 885 if (!TypeID->isStr("Protocol")) 886 break; 887 Context.setObjCProtoType(New->getUnderlyingType()); 888 return; 889 } 890 // Fall through - the typedef name was not a builtin type. 891 } 892 893 // Verify the old decl was also a type. 894 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 895 if (!Old) { 896 Diag(New->getLocation(), diag::err_redefinition_different_kind) 897 << New->getDeclName(); 898 899 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 900 if (OldD->getLocation().isValid()) 901 Diag(OldD->getLocation(), diag::note_previous_definition); 902 903 return New->setInvalidDecl(); 904 } 905 906 // If the old declaration is invalid, just give up here. 907 if (Old->isInvalidDecl()) 908 return New->setInvalidDecl(); 909 910 // Determine the "old" type we'll use for checking and diagnostics. 911 QualType OldType; 912 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 913 OldType = OldTypedef->getUnderlyingType(); 914 else 915 OldType = Context.getTypeDeclType(Old); 916 917 // If the typedef types are not identical, reject them in all languages and 918 // with any extensions enabled. 919 920 if (OldType != New->getUnderlyingType() && 921 Context.getCanonicalType(OldType) != 922 Context.getCanonicalType(New->getUnderlyingType())) { 923 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 924 << New->getUnderlyingType() << OldType; 925 if (Old->getLocation().isValid()) 926 Diag(Old->getLocation(), diag::note_previous_definition); 927 return New->setInvalidDecl(); 928 } 929 930 // The types match. Link up the redeclaration chain if the old 931 // declaration was a typedef. 932 // FIXME: this is a potential source of wierdness if the type 933 // spellings don't match exactly. 934 if (isa<TypedefDecl>(Old)) 935 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 936 937 if (getLangOptions().Microsoft) 938 return; 939 940 if (getLangOptions().CPlusPlus) { 941 // C++ [dcl.typedef]p2: 942 // In a given non-class scope, a typedef specifier can be used to 943 // redefine the name of any type declared in that scope to refer 944 // to the type to which it already refers. 945 if (!isa<CXXRecordDecl>(CurContext)) 946 return; 947 948 // C++0x [dcl.typedef]p4: 949 // In a given class scope, a typedef specifier can be used to redefine 950 // any class-name declared in that scope that is not also a typedef-name 951 // to refer to the type to which it already refers. 952 // 953 // This wording came in via DR424, which was a correction to the 954 // wording in DR56, which accidentally banned code like: 955 // 956 // struct S { 957 // typedef struct A { } A; 958 // }; 959 // 960 // in the C++03 standard. We implement the C++0x semantics, which 961 // allow the above but disallow 962 // 963 // struct S { 964 // typedef int I; 965 // typedef int I; 966 // }; 967 // 968 // since that was the intent of DR56. 969 if (!isa<TypedefDecl >(Old)) 970 return; 971 972 Diag(New->getLocation(), diag::err_redefinition) 973 << New->getDeclName(); 974 Diag(Old->getLocation(), diag::note_previous_definition); 975 return New->setInvalidDecl(); 976 } 977 978 // If we have a redefinition of a typedef in C, emit a warning. This warning 979 // is normally mapped to an error, but can be controlled with 980 // -Wtypedef-redefinition. If either the original or the redefinition is 981 // in a system header, don't emit this for compatibility with GCC. 982 if (getDiagnostics().getSuppressSystemWarnings() && 983 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 984 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 985 return; 986 987 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 988 << New->getDeclName(); 989 Diag(Old->getLocation(), diag::note_previous_definition); 990 return; 991} 992 993/// DeclhasAttr - returns true if decl Declaration already has the target 994/// attribute. 995static bool 996DeclHasAttr(const Decl *D, const Attr *A) { 997 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 998 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 999 if ((*i)->getKind() == A->getKind()) { 1000 // FIXME: Don't hardcode this check 1001 if (OA && isa<OwnershipAttr>(*i)) 1002 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1003 return true; 1004 } 1005 1006 return false; 1007} 1008 1009/// MergeDeclAttributes - append attributes from the Old decl to the New one. 1010static void MergeDeclAttributes(Decl *New, Decl *Old, ASTContext &C) { 1011 if (!Old->hasAttrs()) 1012 return; 1013 // Ensure that any moving of objects within the allocated map is done before 1014 // we process them. 1015 if (!New->hasAttrs()) 1016 New->setAttrs(AttrVec()); 1017 for (Decl::attr_iterator i = Old->attr_begin(), e = Old->attr_end(); i != e; 1018 ++i) { 1019 // FIXME: Make this more general than just checking for Overloadable. 1020 if (!DeclHasAttr(New, *i) && (*i)->getKind() != attr::Overloadable) { 1021 Attr *NewAttr = (*i)->clone(C); 1022 NewAttr->setInherited(true); 1023 New->addAttr(NewAttr); 1024 } 1025 } 1026} 1027 1028namespace { 1029 1030/// Used in MergeFunctionDecl to keep track of function parameters in 1031/// C. 1032struct GNUCompatibleParamWarning { 1033 ParmVarDecl *OldParm; 1034 ParmVarDecl *NewParm; 1035 QualType PromotedType; 1036}; 1037 1038} 1039 1040/// getSpecialMember - get the special member enum for a method. 1041Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1042 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1043 if (Ctor->isCopyConstructor()) 1044 return Sema::CXXCopyConstructor; 1045 1046 return Sema::CXXConstructor; 1047 } 1048 1049 if (isa<CXXDestructorDecl>(MD)) 1050 return Sema::CXXDestructor; 1051 1052 assert(MD->isCopyAssignmentOperator() && 1053 "Must have copy assignment operator"); 1054 return Sema::CXXCopyAssignment; 1055} 1056 1057/// canRedefineFunction - checks if a function can be redefined. Currently, 1058/// only extern inline functions can be redefined, and even then only in 1059/// GNU89 mode. 1060static bool canRedefineFunction(const FunctionDecl *FD, 1061 const LangOptions& LangOpts) { 1062 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1063 FD->isInlineSpecified() && 1064 FD->getStorageClass() == SC_Extern); 1065} 1066 1067/// MergeFunctionDecl - We just parsed a function 'New' from 1068/// declarator D which has the same name and scope as a previous 1069/// declaration 'Old'. Figure out how to resolve this situation, 1070/// merging decls or emitting diagnostics as appropriate. 1071/// 1072/// In C++, New and Old must be declarations that are not 1073/// overloaded. Use IsOverload to determine whether New and Old are 1074/// overloaded, and to select the Old declaration that New should be 1075/// merged with. 1076/// 1077/// Returns true if there was an error, false otherwise. 1078bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1079 // Verify the old decl was also a function. 1080 FunctionDecl *Old = 0; 1081 if (FunctionTemplateDecl *OldFunctionTemplate 1082 = dyn_cast<FunctionTemplateDecl>(OldD)) 1083 Old = OldFunctionTemplate->getTemplatedDecl(); 1084 else 1085 Old = dyn_cast<FunctionDecl>(OldD); 1086 if (!Old) { 1087 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1088 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1089 Diag(Shadow->getTargetDecl()->getLocation(), 1090 diag::note_using_decl_target); 1091 Diag(Shadow->getUsingDecl()->getLocation(), 1092 diag::note_using_decl) << 0; 1093 return true; 1094 } 1095 1096 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1097 << New->getDeclName(); 1098 Diag(OldD->getLocation(), diag::note_previous_definition); 1099 return true; 1100 } 1101 1102 // Determine whether the previous declaration was a definition, 1103 // implicit declaration, or a declaration. 1104 diag::kind PrevDiag; 1105 if (Old->isThisDeclarationADefinition()) 1106 PrevDiag = diag::note_previous_definition; 1107 else if (Old->isImplicit()) 1108 PrevDiag = diag::note_previous_implicit_declaration; 1109 else 1110 PrevDiag = diag::note_previous_declaration; 1111 1112 QualType OldQType = Context.getCanonicalType(Old->getType()); 1113 QualType NewQType = Context.getCanonicalType(New->getType()); 1114 1115 // Don't complain about this if we're in GNU89 mode and the old function 1116 // is an extern inline function. 1117 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1118 New->getStorageClass() == SC_Static && 1119 Old->getStorageClass() != SC_Static && 1120 !canRedefineFunction(Old, getLangOptions())) { 1121 Diag(New->getLocation(), diag::err_static_non_static) 1122 << New; 1123 Diag(Old->getLocation(), PrevDiag); 1124 return true; 1125 } 1126 1127 // If a function is first declared with a calling convention, but is 1128 // later declared or defined without one, the second decl assumes the 1129 // calling convention of the first. 1130 // 1131 // For the new decl, we have to look at the NON-canonical type to tell the 1132 // difference between a function that really doesn't have a calling 1133 // convention and one that is declared cdecl. That's because in 1134 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1135 // because it is the default calling convention. 1136 // 1137 // Note also that we DO NOT return at this point, because we still have 1138 // other tests to run. 1139 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1140 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1141 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1142 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1143 if (OldTypeInfo.getCC() != CC_Default && 1144 NewTypeInfo.getCC() == CC_Default) { 1145 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1146 New->setType(NewQType); 1147 NewQType = Context.getCanonicalType(NewQType); 1148 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1149 NewTypeInfo.getCC())) { 1150 // Calling conventions really aren't compatible, so complain. 1151 Diag(New->getLocation(), diag::err_cconv_change) 1152 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1153 << (OldTypeInfo.getCC() == CC_Default) 1154 << (OldTypeInfo.getCC() == CC_Default ? "" : 1155 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1156 Diag(Old->getLocation(), diag::note_previous_declaration); 1157 return true; 1158 } 1159 1160 // FIXME: diagnose the other way around? 1161 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1162 NewQType = Context.getNoReturnType(NewQType); 1163 New->setType(NewQType); 1164 assert(NewQType.isCanonical()); 1165 } 1166 1167 // Merge regparm attribute. 1168 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1169 if (NewType->getRegParmType()) { 1170 Diag(New->getLocation(), diag::err_regparm_mismatch) 1171 << NewType->getRegParmType() 1172 << OldType->getRegParmType(); 1173 Diag(Old->getLocation(), diag::note_previous_declaration); 1174 return true; 1175 } 1176 1177 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1178 New->setType(NewQType); 1179 assert(NewQType.isCanonical()); 1180 } 1181 1182 if (getLangOptions().CPlusPlus) { 1183 // (C++98 13.1p2): 1184 // Certain function declarations cannot be overloaded: 1185 // -- Function declarations that differ only in the return type 1186 // cannot be overloaded. 1187 QualType OldReturnType 1188 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1189 QualType NewReturnType 1190 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1191 QualType ResQT; 1192 if (OldReturnType != NewReturnType) { 1193 if (NewReturnType->isObjCObjectPointerType() 1194 && OldReturnType->isObjCObjectPointerType()) 1195 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1196 if (ResQT.isNull()) { 1197 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1198 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1199 return true; 1200 } 1201 else 1202 NewQType = ResQT; 1203 } 1204 1205 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1206 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1207 if (OldMethod && NewMethod) { 1208 // Preserve triviality. 1209 NewMethod->setTrivial(OldMethod->isTrivial()); 1210 1211 bool isFriend = NewMethod->getFriendObjectKind(); 1212 1213 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1214 // -- Member function declarations with the same name and the 1215 // same parameter types cannot be overloaded if any of them 1216 // is a static member function declaration. 1217 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1218 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1219 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1220 return true; 1221 } 1222 1223 // C++ [class.mem]p1: 1224 // [...] A member shall not be declared twice in the 1225 // member-specification, except that a nested class or member 1226 // class template can be declared and then later defined. 1227 unsigned NewDiag; 1228 if (isa<CXXConstructorDecl>(OldMethod)) 1229 NewDiag = diag::err_constructor_redeclared; 1230 else if (isa<CXXDestructorDecl>(NewMethod)) 1231 NewDiag = diag::err_destructor_redeclared; 1232 else if (isa<CXXConversionDecl>(NewMethod)) 1233 NewDiag = diag::err_conv_function_redeclared; 1234 else 1235 NewDiag = diag::err_member_redeclared; 1236 1237 Diag(New->getLocation(), NewDiag); 1238 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1239 1240 // Complain if this is an explicit declaration of a special 1241 // member that was initially declared implicitly. 1242 // 1243 // As an exception, it's okay to befriend such methods in order 1244 // to permit the implicit constructor/destructor/operator calls. 1245 } else if (OldMethod->isImplicit()) { 1246 if (isFriend) { 1247 NewMethod->setImplicit(); 1248 } else { 1249 Diag(NewMethod->getLocation(), 1250 diag::err_definition_of_implicitly_declared_member) 1251 << New << getSpecialMember(OldMethod); 1252 return true; 1253 } 1254 } 1255 } 1256 1257 // (C++98 8.3.5p3): 1258 // All declarations for a function shall agree exactly in both the 1259 // return type and the parameter-type-list. 1260 // attributes should be ignored when comparing. 1261 if (Context.getNoReturnType(OldQType, false) == 1262 Context.getNoReturnType(NewQType, false)) 1263 return MergeCompatibleFunctionDecls(New, Old); 1264 1265 // Fall through for conflicting redeclarations and redefinitions. 1266 } 1267 1268 // C: Function types need to be compatible, not identical. This handles 1269 // duplicate function decls like "void f(int); void f(enum X);" properly. 1270 if (!getLangOptions().CPlusPlus && 1271 Context.typesAreCompatible(OldQType, NewQType)) { 1272 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1273 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1274 const FunctionProtoType *OldProto = 0; 1275 if (isa<FunctionNoProtoType>(NewFuncType) && 1276 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1277 // The old declaration provided a function prototype, but the 1278 // new declaration does not. Merge in the prototype. 1279 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1280 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1281 OldProto->arg_type_end()); 1282 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1283 ParamTypes.data(), ParamTypes.size(), 1284 OldProto->isVariadic(), 1285 OldProto->getTypeQuals(), 1286 false, false, 0, 0, 1287 OldProto->getExtInfo()); 1288 New->setType(NewQType); 1289 New->setHasInheritedPrototype(); 1290 1291 // Synthesize a parameter for each argument type. 1292 llvm::SmallVector<ParmVarDecl*, 16> Params; 1293 for (FunctionProtoType::arg_type_iterator 1294 ParamType = OldProto->arg_type_begin(), 1295 ParamEnd = OldProto->arg_type_end(); 1296 ParamType != ParamEnd; ++ParamType) { 1297 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1298 SourceLocation(), 0, 1299 *ParamType, /*TInfo=*/0, 1300 SC_None, SC_None, 1301 0); 1302 Param->setImplicit(); 1303 Params.push_back(Param); 1304 } 1305 1306 New->setParams(Params.data(), Params.size()); 1307 } 1308 1309 return MergeCompatibleFunctionDecls(New, Old); 1310 } 1311 1312 // GNU C permits a K&R definition to follow a prototype declaration 1313 // if the declared types of the parameters in the K&R definition 1314 // match the types in the prototype declaration, even when the 1315 // promoted types of the parameters from the K&R definition differ 1316 // from the types in the prototype. GCC then keeps the types from 1317 // the prototype. 1318 // 1319 // If a variadic prototype is followed by a non-variadic K&R definition, 1320 // the K&R definition becomes variadic. This is sort of an edge case, but 1321 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1322 // C99 6.9.1p8. 1323 if (!getLangOptions().CPlusPlus && 1324 Old->hasPrototype() && !New->hasPrototype() && 1325 New->getType()->getAs<FunctionProtoType>() && 1326 Old->getNumParams() == New->getNumParams()) { 1327 llvm::SmallVector<QualType, 16> ArgTypes; 1328 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1329 const FunctionProtoType *OldProto 1330 = Old->getType()->getAs<FunctionProtoType>(); 1331 const FunctionProtoType *NewProto 1332 = New->getType()->getAs<FunctionProtoType>(); 1333 1334 // Determine whether this is the GNU C extension. 1335 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1336 NewProto->getResultType()); 1337 bool LooseCompatible = !MergedReturn.isNull(); 1338 for (unsigned Idx = 0, End = Old->getNumParams(); 1339 LooseCompatible && Idx != End; ++Idx) { 1340 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1341 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1342 if (Context.typesAreCompatible(OldParm->getType(), 1343 NewProto->getArgType(Idx))) { 1344 ArgTypes.push_back(NewParm->getType()); 1345 } else if (Context.typesAreCompatible(OldParm->getType(), 1346 NewParm->getType(), 1347 /*CompareUnqualified=*/true)) { 1348 GNUCompatibleParamWarning Warn 1349 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1350 Warnings.push_back(Warn); 1351 ArgTypes.push_back(NewParm->getType()); 1352 } else 1353 LooseCompatible = false; 1354 } 1355 1356 if (LooseCompatible) { 1357 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1358 Diag(Warnings[Warn].NewParm->getLocation(), 1359 diag::ext_param_promoted_not_compatible_with_prototype) 1360 << Warnings[Warn].PromotedType 1361 << Warnings[Warn].OldParm->getType(); 1362 if (Warnings[Warn].OldParm->getLocation().isValid()) 1363 Diag(Warnings[Warn].OldParm->getLocation(), 1364 diag::note_previous_declaration); 1365 } 1366 1367 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1368 ArgTypes.size(), 1369 OldProto->isVariadic(), 0, 1370 false, false, 0, 0, 1371 OldProto->getExtInfo())); 1372 return MergeCompatibleFunctionDecls(New, Old); 1373 } 1374 1375 // Fall through to diagnose conflicting types. 1376 } 1377 1378 // A function that has already been declared has been redeclared or defined 1379 // with a different type- show appropriate diagnostic 1380 if (unsigned BuiltinID = Old->getBuiltinID()) { 1381 // The user has declared a builtin function with an incompatible 1382 // signature. 1383 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1384 // The function the user is redeclaring is a library-defined 1385 // function like 'malloc' or 'printf'. Warn about the 1386 // redeclaration, then pretend that we don't know about this 1387 // library built-in. 1388 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1389 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1390 << Old << Old->getType(); 1391 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1392 Old->setInvalidDecl(); 1393 return false; 1394 } 1395 1396 PrevDiag = diag::note_previous_builtin_declaration; 1397 } 1398 1399 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1400 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1401 return true; 1402} 1403 1404/// \brief Completes the merge of two function declarations that are 1405/// known to be compatible. 1406/// 1407/// This routine handles the merging of attributes and other 1408/// properties of function declarations form the old declaration to 1409/// the new declaration, once we know that New is in fact a 1410/// redeclaration of Old. 1411/// 1412/// \returns false 1413bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1414 // Merge the attributes 1415 MergeDeclAttributes(New, Old, Context); 1416 1417 // Merge the storage class. 1418 if (Old->getStorageClass() != SC_Extern && 1419 Old->getStorageClass() != SC_None) 1420 New->setStorageClass(Old->getStorageClass()); 1421 1422 // Merge "pure" flag. 1423 if (Old->isPure()) 1424 New->setPure(); 1425 1426 // Merge the "deleted" flag. 1427 if (Old->isDeleted()) 1428 New->setDeleted(); 1429 1430 if (getLangOptions().CPlusPlus) 1431 return MergeCXXFunctionDecl(New, Old); 1432 1433 return false; 1434} 1435 1436/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1437/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1438/// situation, merging decls or emitting diagnostics as appropriate. 1439/// 1440/// Tentative definition rules (C99 6.9.2p2) are checked by 1441/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1442/// definitions here, since the initializer hasn't been attached. 1443/// 1444void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1445 // If the new decl is already invalid, don't do any other checking. 1446 if (New->isInvalidDecl()) 1447 return; 1448 1449 // Verify the old decl was also a variable. 1450 VarDecl *Old = 0; 1451 if (!Previous.isSingleResult() || 1452 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1453 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1454 << New->getDeclName(); 1455 Diag(Previous.getRepresentativeDecl()->getLocation(), 1456 diag::note_previous_definition); 1457 return New->setInvalidDecl(); 1458 } 1459 1460 // C++ [class.mem]p1: 1461 // A member shall not be declared twice in the member-specification [...] 1462 // 1463 // Here, we need only consider static data members. 1464 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1465 Diag(New->getLocation(), diag::err_duplicate_member) 1466 << New->getIdentifier(); 1467 Diag(Old->getLocation(), diag::note_previous_declaration); 1468 New->setInvalidDecl(); 1469 } 1470 1471 MergeDeclAttributes(New, Old, Context); 1472 1473 // Merge the types 1474 QualType MergedT; 1475 if (getLangOptions().CPlusPlus) { 1476 if (Context.hasSameType(New->getType(), Old->getType())) 1477 MergedT = New->getType(); 1478 // C++ [basic.link]p10: 1479 // [...] the types specified by all declarations referring to a given 1480 // object or function shall be identical, except that declarations for an 1481 // array object can specify array types that differ by the presence or 1482 // absence of a major array bound (8.3.4). 1483 else if (Old->getType()->isIncompleteArrayType() && 1484 New->getType()->isArrayType()) { 1485 CanQual<ArrayType> OldArray 1486 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1487 CanQual<ArrayType> NewArray 1488 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1489 if (OldArray->getElementType() == NewArray->getElementType()) 1490 MergedT = New->getType(); 1491 } else if (Old->getType()->isArrayType() && 1492 New->getType()->isIncompleteArrayType()) { 1493 CanQual<ArrayType> OldArray 1494 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1495 CanQual<ArrayType> NewArray 1496 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1497 if (OldArray->getElementType() == NewArray->getElementType()) 1498 MergedT = Old->getType(); 1499 } else if (New->getType()->isObjCObjectPointerType() 1500 && Old->getType()->isObjCObjectPointerType()) { 1501 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1502 } 1503 } else { 1504 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1505 } 1506 if (MergedT.isNull()) { 1507 Diag(New->getLocation(), diag::err_redefinition_different_type) 1508 << New->getDeclName(); 1509 Diag(Old->getLocation(), diag::note_previous_definition); 1510 return New->setInvalidDecl(); 1511 } 1512 New->setType(MergedT); 1513 1514 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1515 if (New->getStorageClass() == SC_Static && 1516 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1517 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1518 Diag(Old->getLocation(), diag::note_previous_definition); 1519 return New->setInvalidDecl(); 1520 } 1521 // C99 6.2.2p4: 1522 // For an identifier declared with the storage-class specifier 1523 // extern in a scope in which a prior declaration of that 1524 // identifier is visible,23) if the prior declaration specifies 1525 // internal or external linkage, the linkage of the identifier at 1526 // the later declaration is the same as the linkage specified at 1527 // the prior declaration. If no prior declaration is visible, or 1528 // if the prior declaration specifies no linkage, then the 1529 // identifier has external linkage. 1530 if (New->hasExternalStorage() && Old->hasLinkage()) 1531 /* Okay */; 1532 else if (New->getStorageClass() != SC_Static && 1533 Old->getStorageClass() == SC_Static) { 1534 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1535 Diag(Old->getLocation(), diag::note_previous_definition); 1536 return New->setInvalidDecl(); 1537 } 1538 1539 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1540 1541 // FIXME: The test for external storage here seems wrong? We still 1542 // need to check for mismatches. 1543 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1544 // Don't complain about out-of-line definitions of static members. 1545 !(Old->getLexicalDeclContext()->isRecord() && 1546 !New->getLexicalDeclContext()->isRecord())) { 1547 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1548 Diag(Old->getLocation(), diag::note_previous_definition); 1549 return New->setInvalidDecl(); 1550 } 1551 1552 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1553 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1554 Diag(Old->getLocation(), diag::note_previous_definition); 1555 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1556 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1557 Diag(Old->getLocation(), diag::note_previous_definition); 1558 } 1559 1560 // C++ doesn't have tentative definitions, so go right ahead and check here. 1561 const VarDecl *Def; 1562 if (getLangOptions().CPlusPlus && 1563 New->isThisDeclarationADefinition() == VarDecl::Definition && 1564 (Def = Old->getDefinition())) { 1565 Diag(New->getLocation(), diag::err_redefinition) 1566 << New->getDeclName(); 1567 Diag(Def->getLocation(), diag::note_previous_definition); 1568 New->setInvalidDecl(); 1569 return; 1570 } 1571 // c99 6.2.2 P4. 1572 // For an identifier declared with the storage-class specifier extern in a 1573 // scope in which a prior declaration of that identifier is visible, if 1574 // the prior declaration specifies internal or external linkage, the linkage 1575 // of the identifier at the later declaration is the same as the linkage 1576 // specified at the prior declaration. 1577 // FIXME. revisit this code. 1578 if (New->hasExternalStorage() && 1579 Old->getLinkage() == InternalLinkage && 1580 New->getDeclContext() == Old->getDeclContext()) 1581 New->setStorageClass(Old->getStorageClass()); 1582 1583 // Keep a chain of previous declarations. 1584 New->setPreviousDeclaration(Old); 1585 1586 // Inherit access appropriately. 1587 New->setAccess(Old->getAccess()); 1588} 1589 1590/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1591/// no declarator (e.g. "struct foo;") is parsed. 1592Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1593 DeclSpec &DS) { 1594 // FIXME: Error on inline/virtual/explicit 1595 // FIXME: Warn on useless __thread 1596 // FIXME: Warn on useless const/volatile 1597 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1598 // FIXME: Warn on useless attributes 1599 Decl *TagD = 0; 1600 TagDecl *Tag = 0; 1601 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1602 DS.getTypeSpecType() == DeclSpec::TST_struct || 1603 DS.getTypeSpecType() == DeclSpec::TST_union || 1604 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1605 TagD = DS.getRepAsDecl(); 1606 1607 if (!TagD) // We probably had an error 1608 return 0; 1609 1610 // Note that the above type specs guarantee that the 1611 // type rep is a Decl, whereas in many of the others 1612 // it's a Type. 1613 Tag = dyn_cast<TagDecl>(TagD); 1614 } 1615 1616 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1617 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1618 // or incomplete types shall not be restrict-qualified." 1619 if (TypeQuals & DeclSpec::TQ_restrict) 1620 Diag(DS.getRestrictSpecLoc(), 1621 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1622 << DS.getSourceRange(); 1623 } 1624 1625 if (DS.isFriendSpecified()) { 1626 // If we're dealing with a class template decl, assume that the 1627 // template routines are handling it. 1628 if (TagD && isa<ClassTemplateDecl>(TagD)) 1629 return 0; 1630 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1631 } 1632 1633 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1634 ProcessDeclAttributeList(S, Record, DS.getAttributes()); 1635 1636 if (!Record->getDeclName() && Record->isDefinition() && 1637 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1638 if (getLangOptions().CPlusPlus || 1639 Record->getDeclContext()->isRecord()) 1640 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1641 1642 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1643 << DS.getSourceRange(); 1644 } 1645 1646 // Microsoft allows unnamed struct/union fields. Don't complain 1647 // about them. 1648 // FIXME: Should we support Microsoft's extensions in this area? 1649 if (Record->getDeclName() && getLangOptions().Microsoft) 1650 return Tag; 1651 } 1652 1653 if (getLangOptions().CPlusPlus && 1654 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1655 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1656 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1657 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1658 Diag(Enum->getLocation(), diag::ext_no_declarators) 1659 << DS.getSourceRange(); 1660 1661 if (!DS.isMissingDeclaratorOk() && 1662 DS.getTypeSpecType() != DeclSpec::TST_error) { 1663 // Warn about typedefs of enums without names, since this is an 1664 // extension in both Microsoft and GNU. 1665 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1666 Tag && isa<EnumDecl>(Tag)) { 1667 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1668 << DS.getSourceRange(); 1669 return Tag; 1670 } 1671 1672 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1673 << DS.getSourceRange(); 1674 } 1675 1676 return TagD; 1677} 1678 1679/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1680/// builds a statement for it and returns it so it is evaluated. 1681StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1682 StmtResult R; 1683 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1684 Expr *Exp = DS.getRepAsExpr(); 1685 QualType Ty = Exp->getType(); 1686 if (Ty->isPointerType()) { 1687 do 1688 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1689 while (Ty->isPointerType()); 1690 } 1691 if (Ty->isVariableArrayType()) { 1692 R = ActOnExprStmt(MakeFullExpr(Exp)); 1693 } 1694 } 1695 return R; 1696} 1697 1698/// We are trying to inject an anonymous member into the given scope; 1699/// check if there's an existing declaration that can't be overloaded. 1700/// 1701/// \return true if this is a forbidden redeclaration 1702static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1703 Scope *S, 1704 DeclContext *Owner, 1705 DeclarationName Name, 1706 SourceLocation NameLoc, 1707 unsigned diagnostic) { 1708 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1709 Sema::ForRedeclaration); 1710 if (!SemaRef.LookupName(R, S)) return false; 1711 1712 if (R.getAsSingle<TagDecl>()) 1713 return false; 1714 1715 // Pick a representative declaration. 1716 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1717 assert(PrevDecl && "Expected a non-null Decl"); 1718 1719 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1720 return false; 1721 1722 SemaRef.Diag(NameLoc, diagnostic) << Name; 1723 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1724 1725 return true; 1726} 1727 1728/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1729/// anonymous struct or union AnonRecord into the owning context Owner 1730/// and scope S. This routine will be invoked just after we realize 1731/// that an unnamed union or struct is actually an anonymous union or 1732/// struct, e.g., 1733/// 1734/// @code 1735/// union { 1736/// int i; 1737/// float f; 1738/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1739/// // f into the surrounding scope.x 1740/// @endcode 1741/// 1742/// This routine is recursive, injecting the names of nested anonymous 1743/// structs/unions into the owning context and scope as well. 1744static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1745 DeclContext *Owner, 1746 RecordDecl *AnonRecord, 1747 AccessSpecifier AS) { 1748 unsigned diagKind 1749 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1750 : diag::err_anonymous_struct_member_redecl; 1751 1752 bool Invalid = false; 1753 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1754 FEnd = AnonRecord->field_end(); 1755 F != FEnd; ++F) { 1756 if ((*F)->getDeclName()) { 1757 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1758 (*F)->getLocation(), diagKind)) { 1759 // C++ [class.union]p2: 1760 // The names of the members of an anonymous union shall be 1761 // distinct from the names of any other entity in the 1762 // scope in which the anonymous union is declared. 1763 Invalid = true; 1764 } else { 1765 // C++ [class.union]p2: 1766 // For the purpose of name lookup, after the anonymous union 1767 // definition, the members of the anonymous union are 1768 // considered to have been defined in the scope in which the 1769 // anonymous union is declared. 1770 Owner->makeDeclVisibleInContext(*F); 1771 S->AddDecl(*F); 1772 SemaRef.IdResolver.AddDecl(*F); 1773 1774 // That includes picking up the appropriate access specifier. 1775 if (AS != AS_none) (*F)->setAccess(AS); 1776 } 1777 } else if (const RecordType *InnerRecordType 1778 = (*F)->getType()->getAs<RecordType>()) { 1779 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1780 if (InnerRecord->isAnonymousStructOrUnion()) 1781 Invalid = Invalid || 1782 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1783 InnerRecord, AS); 1784 } 1785 } 1786 1787 return Invalid; 1788} 1789 1790/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1791/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1792/// illegal input values are mapped to SC_None. 1793static StorageClass 1794StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1795 switch (StorageClassSpec) { 1796 case DeclSpec::SCS_unspecified: return SC_None; 1797 case DeclSpec::SCS_extern: return SC_Extern; 1798 case DeclSpec::SCS_static: return SC_Static; 1799 case DeclSpec::SCS_auto: return SC_Auto; 1800 case DeclSpec::SCS_register: return SC_Register; 1801 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1802 // Illegal SCSs map to None: error reporting is up to the caller. 1803 case DeclSpec::SCS_mutable: // Fall through. 1804 case DeclSpec::SCS_typedef: return SC_None; 1805 } 1806 llvm_unreachable("unknown storage class specifier"); 1807} 1808 1809/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1810/// a StorageClass. Any error reporting is up to the caller: 1811/// illegal input values are mapped to SC_None. 1812static StorageClass 1813StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1814 switch (StorageClassSpec) { 1815 case DeclSpec::SCS_unspecified: return SC_None; 1816 case DeclSpec::SCS_extern: return SC_Extern; 1817 case DeclSpec::SCS_static: return SC_Static; 1818 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1819 // Illegal SCSs map to None: error reporting is up to the caller. 1820 case DeclSpec::SCS_auto: // Fall through. 1821 case DeclSpec::SCS_mutable: // Fall through. 1822 case DeclSpec::SCS_register: // Fall through. 1823 case DeclSpec::SCS_typedef: return SC_None; 1824 } 1825 llvm_unreachable("unknown storage class specifier"); 1826} 1827 1828/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1829/// anonymous structure or union. Anonymous unions are a C++ feature 1830/// (C++ [class.union]) and a GNU C extension; anonymous structures 1831/// are a GNU C and GNU C++ extension. 1832Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1833 AccessSpecifier AS, 1834 RecordDecl *Record) { 1835 DeclContext *Owner = Record->getDeclContext(); 1836 1837 // Diagnose whether this anonymous struct/union is an extension. 1838 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1839 Diag(Record->getLocation(), diag::ext_anonymous_union); 1840 else if (!Record->isUnion()) 1841 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1842 1843 // C and C++ require different kinds of checks for anonymous 1844 // structs/unions. 1845 bool Invalid = false; 1846 if (getLangOptions().CPlusPlus) { 1847 const char* PrevSpec = 0; 1848 unsigned DiagID; 1849 // C++ [class.union]p3: 1850 // Anonymous unions declared in a named namespace or in the 1851 // global namespace shall be declared static. 1852 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1853 (isa<TranslationUnitDecl>(Owner) || 1854 (isa<NamespaceDecl>(Owner) && 1855 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1856 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1857 Invalid = true; 1858 1859 // Recover by adding 'static'. 1860 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1861 PrevSpec, DiagID); 1862 } 1863 // C++ [class.union]p3: 1864 // A storage class is not allowed in a declaration of an 1865 // anonymous union in a class scope. 1866 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1867 isa<RecordDecl>(Owner)) { 1868 Diag(DS.getStorageClassSpecLoc(), 1869 diag::err_anonymous_union_with_storage_spec); 1870 Invalid = true; 1871 1872 // Recover by removing the storage specifier. 1873 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1874 PrevSpec, DiagID); 1875 } 1876 1877 // C++ [class.union]p2: 1878 // The member-specification of an anonymous union shall only 1879 // define non-static data members. [Note: nested types and 1880 // functions cannot be declared within an anonymous union. ] 1881 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1882 MemEnd = Record->decls_end(); 1883 Mem != MemEnd; ++Mem) { 1884 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1885 // C++ [class.union]p3: 1886 // An anonymous union shall not have private or protected 1887 // members (clause 11). 1888 assert(FD->getAccess() != AS_none); 1889 if (FD->getAccess() != AS_public) { 1890 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1891 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1892 Invalid = true; 1893 } 1894 1895 if (CheckNontrivialField(FD)) 1896 Invalid = true; 1897 } else if ((*Mem)->isImplicit()) { 1898 // Any implicit members are fine. 1899 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1900 // This is a type that showed up in an 1901 // elaborated-type-specifier inside the anonymous struct or 1902 // union, but which actually declares a type outside of the 1903 // anonymous struct or union. It's okay. 1904 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1905 if (!MemRecord->isAnonymousStructOrUnion() && 1906 MemRecord->getDeclName()) { 1907 // Visual C++ allows type definition in anonymous struct or union. 1908 if (getLangOptions().Microsoft) 1909 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 1910 << (int)Record->isUnion(); 1911 else { 1912 // This is a nested type declaration. 1913 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1914 << (int)Record->isUnion(); 1915 Invalid = true; 1916 } 1917 } 1918 } else if (isa<AccessSpecDecl>(*Mem)) { 1919 // Any access specifier is fine. 1920 } else { 1921 // We have something that isn't a non-static data 1922 // member. Complain about it. 1923 unsigned DK = diag::err_anonymous_record_bad_member; 1924 if (isa<TypeDecl>(*Mem)) 1925 DK = diag::err_anonymous_record_with_type; 1926 else if (isa<FunctionDecl>(*Mem)) 1927 DK = diag::err_anonymous_record_with_function; 1928 else if (isa<VarDecl>(*Mem)) 1929 DK = diag::err_anonymous_record_with_static; 1930 1931 // Visual C++ allows type definition in anonymous struct or union. 1932 if (getLangOptions().Microsoft && 1933 DK == diag::err_anonymous_record_with_type) 1934 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 1935 << (int)Record->isUnion(); 1936 else { 1937 Diag((*Mem)->getLocation(), DK) 1938 << (int)Record->isUnion(); 1939 Invalid = true; 1940 } 1941 } 1942 } 1943 } 1944 1945 if (!Record->isUnion() && !Owner->isRecord()) { 1946 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1947 << (int)getLangOptions().CPlusPlus; 1948 Invalid = true; 1949 } 1950 1951 // Mock up a declarator. 1952 Declarator Dc(DS, Declarator::TypeNameContext); 1953 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1954 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1955 1956 // Create a declaration for this anonymous struct/union. 1957 NamedDecl *Anon = 0; 1958 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1959 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1960 /*IdentifierInfo=*/0, 1961 Context.getTypeDeclType(Record), 1962 TInfo, 1963 /*BitWidth=*/0, /*Mutable=*/false); 1964 Anon->setAccess(AS); 1965 if (getLangOptions().CPlusPlus) 1966 FieldCollector->Add(cast<FieldDecl>(Anon)); 1967 } else { 1968 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1969 assert(SCSpec != DeclSpec::SCS_typedef && 1970 "Parser allowed 'typedef' as storage class VarDecl."); 1971 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1972 if (SCSpec == DeclSpec::SCS_mutable) { 1973 // mutable can only appear on non-static class members, so it's always 1974 // an error here 1975 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1976 Invalid = true; 1977 SC = SC_None; 1978 } 1979 SCSpec = DS.getStorageClassSpecAsWritten(); 1980 VarDecl::StorageClass SCAsWritten 1981 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1982 1983 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1984 /*IdentifierInfo=*/0, 1985 Context.getTypeDeclType(Record), 1986 TInfo, SC, SCAsWritten); 1987 } 1988 Anon->setImplicit(); 1989 1990 // Add the anonymous struct/union object to the current 1991 // context. We'll be referencing this object when we refer to one of 1992 // its members. 1993 Owner->addDecl(Anon); 1994 1995 // Inject the members of the anonymous struct/union into the owning 1996 // context and into the identifier resolver chain for name lookup 1997 // purposes. 1998 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1999 Invalid = true; 2000 2001 // Mark this as an anonymous struct/union type. Note that we do not 2002 // do this until after we have already checked and injected the 2003 // members of this anonymous struct/union type, because otherwise 2004 // the members could be injected twice: once by DeclContext when it 2005 // builds its lookup table, and once by 2006 // InjectAnonymousStructOrUnionMembers. 2007 Record->setAnonymousStructOrUnion(true); 2008 2009 if (Invalid) 2010 Anon->setInvalidDecl(); 2011 2012 return Anon; 2013} 2014 2015 2016/// GetNameForDeclarator - Determine the full declaration name for the 2017/// given Declarator. 2018DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2019 return GetNameFromUnqualifiedId(D.getName()); 2020} 2021 2022/// \brief Retrieves the declaration name from a parsed unqualified-id. 2023DeclarationNameInfo 2024Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2025 DeclarationNameInfo NameInfo; 2026 NameInfo.setLoc(Name.StartLocation); 2027 2028 switch (Name.getKind()) { 2029 2030 case UnqualifiedId::IK_Identifier: 2031 NameInfo.setName(Name.Identifier); 2032 NameInfo.setLoc(Name.StartLocation); 2033 return NameInfo; 2034 2035 case UnqualifiedId::IK_OperatorFunctionId: 2036 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2037 Name.OperatorFunctionId.Operator)); 2038 NameInfo.setLoc(Name.StartLocation); 2039 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2040 = Name.OperatorFunctionId.SymbolLocations[0]; 2041 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2042 = Name.EndLocation.getRawEncoding(); 2043 return NameInfo; 2044 2045 case UnqualifiedId::IK_LiteralOperatorId: 2046 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2047 Name.Identifier)); 2048 NameInfo.setLoc(Name.StartLocation); 2049 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2050 return NameInfo; 2051 2052 case UnqualifiedId::IK_ConversionFunctionId: { 2053 TypeSourceInfo *TInfo; 2054 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2055 if (Ty.isNull()) 2056 return DeclarationNameInfo(); 2057 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2058 Context.getCanonicalType(Ty))); 2059 NameInfo.setLoc(Name.StartLocation); 2060 NameInfo.setNamedTypeInfo(TInfo); 2061 return NameInfo; 2062 } 2063 2064 case UnqualifiedId::IK_ConstructorName: { 2065 TypeSourceInfo *TInfo; 2066 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2067 if (Ty.isNull()) 2068 return DeclarationNameInfo(); 2069 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2070 Context.getCanonicalType(Ty))); 2071 NameInfo.setLoc(Name.StartLocation); 2072 NameInfo.setNamedTypeInfo(TInfo); 2073 return NameInfo; 2074 } 2075 2076 case UnqualifiedId::IK_ConstructorTemplateId: { 2077 // In well-formed code, we can only have a constructor 2078 // template-id that refers to the current context, so go there 2079 // to find the actual type being constructed. 2080 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2081 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2082 return DeclarationNameInfo(); 2083 2084 // Determine the type of the class being constructed. 2085 QualType CurClassType = Context.getTypeDeclType(CurClass); 2086 2087 // FIXME: Check two things: that the template-id names the same type as 2088 // CurClassType, and that the template-id does not occur when the name 2089 // was qualified. 2090 2091 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2092 Context.getCanonicalType(CurClassType))); 2093 NameInfo.setLoc(Name.StartLocation); 2094 // FIXME: should we retrieve TypeSourceInfo? 2095 NameInfo.setNamedTypeInfo(0); 2096 return NameInfo; 2097 } 2098 2099 case UnqualifiedId::IK_DestructorName: { 2100 TypeSourceInfo *TInfo; 2101 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2102 if (Ty.isNull()) 2103 return DeclarationNameInfo(); 2104 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2105 Context.getCanonicalType(Ty))); 2106 NameInfo.setLoc(Name.StartLocation); 2107 NameInfo.setNamedTypeInfo(TInfo); 2108 return NameInfo; 2109 } 2110 2111 case UnqualifiedId::IK_TemplateId: { 2112 TemplateName TName = Name.TemplateId->Template.get(); 2113 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2114 return Context.getNameForTemplate(TName, TNameLoc); 2115 } 2116 2117 } // switch (Name.getKind()) 2118 2119 assert(false && "Unknown name kind"); 2120 return DeclarationNameInfo(); 2121} 2122 2123/// isNearlyMatchingFunction - Determine whether the C++ functions 2124/// Declaration and Definition are "nearly" matching. This heuristic 2125/// is used to improve diagnostics in the case where an out-of-line 2126/// function definition doesn't match any declaration within 2127/// the class or namespace. 2128static bool isNearlyMatchingFunction(ASTContext &Context, 2129 FunctionDecl *Declaration, 2130 FunctionDecl *Definition) { 2131 if (Declaration->param_size() != Definition->param_size()) 2132 return false; 2133 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2134 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2135 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2136 2137 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2138 DefParamTy.getNonReferenceType())) 2139 return false; 2140 } 2141 2142 return true; 2143} 2144 2145/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2146/// declarator needs to be rebuilt in the current instantiation. 2147/// Any bits of declarator which appear before the name are valid for 2148/// consideration here. That's specifically the type in the decl spec 2149/// and the base type in any member-pointer chunks. 2150static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2151 DeclarationName Name) { 2152 // The types we specifically need to rebuild are: 2153 // - typenames, typeofs, and decltypes 2154 // - types which will become injected class names 2155 // Of course, we also need to rebuild any type referencing such a 2156 // type. It's safest to just say "dependent", but we call out a 2157 // few cases here. 2158 2159 DeclSpec &DS = D.getMutableDeclSpec(); 2160 switch (DS.getTypeSpecType()) { 2161 case DeclSpec::TST_typename: 2162 case DeclSpec::TST_typeofType: 2163 case DeclSpec::TST_decltype: { 2164 // Grab the type from the parser. 2165 TypeSourceInfo *TSI = 0; 2166 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2167 if (T.isNull() || !T->isDependentType()) break; 2168 2169 // Make sure there's a type source info. This isn't really much 2170 // of a waste; most dependent types should have type source info 2171 // attached already. 2172 if (!TSI) 2173 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2174 2175 // Rebuild the type in the current instantiation. 2176 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2177 if (!TSI) return true; 2178 2179 // Store the new type back in the decl spec. 2180 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2181 DS.UpdateTypeRep(LocType); 2182 break; 2183 } 2184 2185 case DeclSpec::TST_typeofExpr: { 2186 Expr *E = DS.getRepAsExpr(); 2187 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2188 if (Result.isInvalid()) return true; 2189 DS.UpdateExprRep(Result.get()); 2190 break; 2191 } 2192 2193 default: 2194 // Nothing to do for these decl specs. 2195 break; 2196 } 2197 2198 // It doesn't matter what order we do this in. 2199 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2200 DeclaratorChunk &Chunk = D.getTypeObject(I); 2201 2202 // The only type information in the declarator which can come 2203 // before the declaration name is the base type of a member 2204 // pointer. 2205 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2206 continue; 2207 2208 // Rebuild the scope specifier in-place. 2209 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2210 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2211 return true; 2212 } 2213 2214 return false; 2215} 2216 2217Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2218 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2219} 2220 2221Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2222 MultiTemplateParamsArg TemplateParamLists, 2223 bool IsFunctionDefinition) { 2224 // TODO: consider using NameInfo for diagnostic. 2225 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2226 DeclarationName Name = NameInfo.getName(); 2227 2228 // All of these full declarators require an identifier. If it doesn't have 2229 // one, the ParsedFreeStandingDeclSpec action should be used. 2230 if (!Name) { 2231 if (!D.isInvalidType()) // Reject this if we think it is valid. 2232 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2233 diag::err_declarator_need_ident) 2234 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2235 return 0; 2236 } 2237 2238 // The scope passed in may not be a decl scope. Zip up the scope tree until 2239 // we find one that is. 2240 while ((S->getFlags() & Scope::DeclScope) == 0 || 2241 (S->getFlags() & Scope::TemplateParamScope) != 0) 2242 S = S->getParent(); 2243 2244 DeclContext *DC = CurContext; 2245 if (D.getCXXScopeSpec().isInvalid()) 2246 D.setInvalidType(); 2247 else if (D.getCXXScopeSpec().isSet()) { 2248 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2249 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2250 if (!DC) { 2251 // If we could not compute the declaration context, it's because the 2252 // declaration context is dependent but does not refer to a class, 2253 // class template, or class template partial specialization. Complain 2254 // and return early, to avoid the coming semantic disaster. 2255 Diag(D.getIdentifierLoc(), 2256 diag::err_template_qualified_declarator_no_match) 2257 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2258 << D.getCXXScopeSpec().getRange(); 2259 return 0; 2260 } 2261 2262 bool IsDependentContext = DC->isDependentContext(); 2263 2264 if (!IsDependentContext && 2265 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2266 return 0; 2267 2268 if (isa<CXXRecordDecl>(DC)) { 2269 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2270 Diag(D.getIdentifierLoc(), 2271 diag::err_member_def_undefined_record) 2272 << Name << DC << D.getCXXScopeSpec().getRange(); 2273 D.setInvalidType(); 2274 } else if (isa<CXXRecordDecl>(CurContext) && 2275 !D.getDeclSpec().isFriendSpecified()) { 2276 // The user provided a superfluous scope specifier inside a class 2277 // definition: 2278 // 2279 // class X { 2280 // void X::f(); 2281 // }; 2282 if (CurContext->Equals(DC)) 2283 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2284 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2285 else 2286 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2287 << Name << D.getCXXScopeSpec().getRange(); 2288 2289 // Pretend that this qualifier was not here. 2290 D.getCXXScopeSpec().clear(); 2291 } 2292 } 2293 2294 // Check whether we need to rebuild the type of the given 2295 // declaration in the current instantiation. 2296 if (EnteringContext && IsDependentContext && 2297 TemplateParamLists.size() != 0) { 2298 ContextRAII SavedContext(*this, DC); 2299 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2300 D.setInvalidType(); 2301 } 2302 } 2303 2304 // C++ [class.mem]p13: 2305 // If T is the name of a class, then each of the following shall have a 2306 // name different from T: 2307 // - every static data member of class T; 2308 // - every member function of class T 2309 // - every member of class T that is itself a type; 2310 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2311 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2312 Diag(D.getIdentifierLoc(), diag::err_member_name_of_class) 2313 << Name; 2314 2315 // If this is a typedef, we'll end up spewing multiple diagnostics. 2316 // Just return early; it's safer. 2317 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2318 return 0; 2319 } 2320 2321 NamedDecl *New; 2322 2323 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2324 QualType R = TInfo->getType(); 2325 2326 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2327 ForRedeclaration); 2328 2329 // See if this is a redefinition of a variable in the same scope. 2330 if (!D.getCXXScopeSpec().isSet()) { 2331 bool IsLinkageLookup = false; 2332 2333 // If the declaration we're planning to build will be a function 2334 // or object with linkage, then look for another declaration with 2335 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2336 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2337 /* Do nothing*/; 2338 else if (R->isFunctionType()) { 2339 if (CurContext->isFunctionOrMethod() || 2340 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2341 IsLinkageLookup = true; 2342 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2343 IsLinkageLookup = true; 2344 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2345 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2346 IsLinkageLookup = true; 2347 2348 if (IsLinkageLookup) 2349 Previous.clear(LookupRedeclarationWithLinkage); 2350 2351 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2352 } else { // Something like "int foo::x;" 2353 LookupQualifiedName(Previous, DC); 2354 2355 // Don't consider using declarations as previous declarations for 2356 // out-of-line members. 2357 RemoveUsingDecls(Previous); 2358 2359 // C++ 7.3.1.2p2: 2360 // Members (including explicit specializations of templates) of a named 2361 // namespace can also be defined outside that namespace by explicit 2362 // qualification of the name being defined, provided that the entity being 2363 // defined was already declared in the namespace and the definition appears 2364 // after the point of declaration in a namespace that encloses the 2365 // declarations namespace. 2366 // 2367 // Note that we only check the context at this point. We don't yet 2368 // have enough information to make sure that PrevDecl is actually 2369 // the declaration we want to match. For example, given: 2370 // 2371 // class X { 2372 // void f(); 2373 // void f(float); 2374 // }; 2375 // 2376 // void X::f(int) { } // ill-formed 2377 // 2378 // In this case, PrevDecl will point to the overload set 2379 // containing the two f's declared in X, but neither of them 2380 // matches. 2381 2382 // First check whether we named the global scope. 2383 if (isa<TranslationUnitDecl>(DC)) { 2384 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2385 << Name << D.getCXXScopeSpec().getRange(); 2386 } else { 2387 DeclContext *Cur = CurContext; 2388 while (isa<LinkageSpecDecl>(Cur)) 2389 Cur = Cur->getParent(); 2390 if (!Cur->Encloses(DC)) { 2391 // The qualifying scope doesn't enclose the original declaration. 2392 // Emit diagnostic based on current scope. 2393 SourceLocation L = D.getIdentifierLoc(); 2394 SourceRange R = D.getCXXScopeSpec().getRange(); 2395 if (isa<FunctionDecl>(Cur)) 2396 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2397 else 2398 Diag(L, diag::err_invalid_declarator_scope) 2399 << Name << cast<NamedDecl>(DC) << R; 2400 D.setInvalidType(); 2401 } 2402 } 2403 } 2404 2405 if (Previous.isSingleResult() && 2406 Previous.getFoundDecl()->isTemplateParameter()) { 2407 // Maybe we will complain about the shadowed template parameter. 2408 if (!D.isInvalidType()) 2409 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2410 Previous.getFoundDecl())) 2411 D.setInvalidType(); 2412 2413 // Just pretend that we didn't see the previous declaration. 2414 Previous.clear(); 2415 } 2416 2417 // In C++, the previous declaration we find might be a tag type 2418 // (class or enum). In this case, the new declaration will hide the 2419 // tag type. Note that this does does not apply if we're declaring a 2420 // typedef (C++ [dcl.typedef]p4). 2421 if (Previous.isSingleTagDecl() && 2422 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2423 Previous.clear(); 2424 2425 bool Redeclaration = false; 2426 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2427 if (TemplateParamLists.size()) { 2428 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2429 return 0; 2430 } 2431 2432 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2433 } else if (R->isFunctionType()) { 2434 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2435 move(TemplateParamLists), 2436 IsFunctionDefinition, Redeclaration); 2437 } else { 2438 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2439 move(TemplateParamLists), 2440 Redeclaration); 2441 } 2442 2443 if (New == 0) 2444 return 0; 2445 2446 // If this has an identifier and is not an invalid redeclaration or 2447 // function template specialization, add it to the scope stack. 2448 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2449 PushOnScopeChains(New, S); 2450 2451 return New; 2452} 2453 2454/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2455/// types into constant array types in certain situations which would otherwise 2456/// be errors (for GCC compatibility). 2457static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2458 ASTContext &Context, 2459 bool &SizeIsNegative, 2460 llvm::APSInt &Oversized) { 2461 // This method tries to turn a variable array into a constant 2462 // array even when the size isn't an ICE. This is necessary 2463 // for compatibility with code that depends on gcc's buggy 2464 // constant expression folding, like struct {char x[(int)(char*)2];} 2465 SizeIsNegative = false; 2466 Oversized = 0; 2467 2468 if (T->isDependentType()) 2469 return QualType(); 2470 2471 QualifierCollector Qs; 2472 const Type *Ty = Qs.strip(T); 2473 2474 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2475 QualType Pointee = PTy->getPointeeType(); 2476 QualType FixedType = 2477 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2478 Oversized); 2479 if (FixedType.isNull()) return FixedType; 2480 FixedType = Context.getPointerType(FixedType); 2481 return Qs.apply(FixedType); 2482 } 2483 2484 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2485 if (!VLATy) 2486 return QualType(); 2487 // FIXME: We should probably handle this case 2488 if (VLATy->getElementType()->isVariablyModifiedType()) 2489 return QualType(); 2490 2491 Expr::EvalResult EvalResult; 2492 if (!VLATy->getSizeExpr() || 2493 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2494 !EvalResult.Val.isInt()) 2495 return QualType(); 2496 2497 // Check whether the array size is negative. 2498 llvm::APSInt &Res = EvalResult.Val.getInt(); 2499 if (Res.isSigned() && Res.isNegative()) { 2500 SizeIsNegative = true; 2501 return QualType(); 2502 } 2503 2504 // Check whether the array is too large to be addressed. 2505 unsigned ActiveSizeBits 2506 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2507 Res); 2508 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2509 Oversized = Res; 2510 return QualType(); 2511 } 2512 2513 return Context.getConstantArrayType(VLATy->getElementType(), 2514 Res, ArrayType::Normal, 0); 2515} 2516 2517/// \brief Register the given locally-scoped external C declaration so 2518/// that it can be found later for redeclarations 2519void 2520Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2521 const LookupResult &Previous, 2522 Scope *S) { 2523 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2524 "Decl is not a locally-scoped decl!"); 2525 // Note that we have a locally-scoped external with this name. 2526 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2527 2528 if (!Previous.isSingleResult()) 2529 return; 2530 2531 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2532 2533 // If there was a previous declaration of this variable, it may be 2534 // in our identifier chain. Update the identifier chain with the new 2535 // declaration. 2536 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2537 // The previous declaration was found on the identifer resolver 2538 // chain, so remove it from its scope. 2539 while (S && !S->isDeclScope(PrevDecl)) 2540 S = S->getParent(); 2541 2542 if (S) 2543 S->RemoveDecl(PrevDecl); 2544 } 2545} 2546 2547/// \brief Diagnose function specifiers on a declaration of an identifier that 2548/// does not identify a function. 2549void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2550 // FIXME: We should probably indicate the identifier in question to avoid 2551 // confusion for constructs like "inline int a(), b;" 2552 if (D.getDeclSpec().isInlineSpecified()) 2553 Diag(D.getDeclSpec().getInlineSpecLoc(), 2554 diag::err_inline_non_function); 2555 2556 if (D.getDeclSpec().isVirtualSpecified()) 2557 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2558 diag::err_virtual_non_function); 2559 2560 if (D.getDeclSpec().isExplicitSpecified()) 2561 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2562 diag::err_explicit_non_function); 2563} 2564 2565NamedDecl* 2566Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2567 QualType R, TypeSourceInfo *TInfo, 2568 LookupResult &Previous, bool &Redeclaration) { 2569 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2570 if (D.getCXXScopeSpec().isSet()) { 2571 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2572 << D.getCXXScopeSpec().getRange(); 2573 D.setInvalidType(); 2574 // Pretend we didn't see the scope specifier. 2575 DC = CurContext; 2576 Previous.clear(); 2577 } 2578 2579 if (getLangOptions().CPlusPlus) { 2580 // Check that there are no default arguments (C++ only). 2581 CheckExtraCXXDefaultArguments(D); 2582 } 2583 2584 DiagnoseFunctionSpecifiers(D); 2585 2586 if (D.getDeclSpec().isThreadSpecified()) 2587 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2588 2589 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2590 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2591 << D.getName().getSourceRange(); 2592 return 0; 2593 } 2594 2595 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2596 if (!NewTD) return 0; 2597 2598 // Handle attributes prior to checking for duplicates in MergeVarDecl 2599 ProcessDeclAttributes(S, NewTD, D); 2600 2601 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2602 // then it shall have block scope. 2603 // Note that variably modified types must be fixed before merging the decl so 2604 // that redeclarations will match. 2605 QualType T = NewTD->getUnderlyingType(); 2606 if (T->isVariablyModifiedType()) { 2607 getCurFunction()->setHasBranchProtectedScope(); 2608 2609 if (S->getFnParent() == 0) { 2610 bool SizeIsNegative; 2611 llvm::APSInt Oversized; 2612 QualType FixedTy = 2613 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2614 Oversized); 2615 if (!FixedTy.isNull()) { 2616 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2617 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2618 } else { 2619 if (SizeIsNegative) 2620 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2621 else if (T->isVariableArrayType()) 2622 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2623 else if (Oversized.getBoolValue()) 2624 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2625 << Oversized.toString(10); 2626 else 2627 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2628 NewTD->setInvalidDecl(); 2629 } 2630 } 2631 } 2632 2633 // Merge the decl with the existing one if appropriate. If the decl is 2634 // in an outer scope, it isn't the same thing. 2635 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2636 if (!Previous.empty()) { 2637 Redeclaration = true; 2638 MergeTypeDefDecl(NewTD, Previous); 2639 } 2640 2641 // If this is the C FILE type, notify the AST context. 2642 if (IdentifierInfo *II = NewTD->getIdentifier()) 2643 if (!NewTD->isInvalidDecl() && 2644 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2645 if (II->isStr("FILE")) 2646 Context.setFILEDecl(NewTD); 2647 else if (II->isStr("jmp_buf")) 2648 Context.setjmp_bufDecl(NewTD); 2649 else if (II->isStr("sigjmp_buf")) 2650 Context.setsigjmp_bufDecl(NewTD); 2651 else if (II->isStr("__builtin_va_list")) 2652 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2653 } 2654 2655 return NewTD; 2656} 2657 2658/// \brief Determines whether the given declaration is an out-of-scope 2659/// previous declaration. 2660/// 2661/// This routine should be invoked when name lookup has found a 2662/// previous declaration (PrevDecl) that is not in the scope where a 2663/// new declaration by the same name is being introduced. If the new 2664/// declaration occurs in a local scope, previous declarations with 2665/// linkage may still be considered previous declarations (C99 2666/// 6.2.2p4-5, C++ [basic.link]p6). 2667/// 2668/// \param PrevDecl the previous declaration found by name 2669/// lookup 2670/// 2671/// \param DC the context in which the new declaration is being 2672/// declared. 2673/// 2674/// \returns true if PrevDecl is an out-of-scope previous declaration 2675/// for a new delcaration with the same name. 2676static bool 2677isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2678 ASTContext &Context) { 2679 if (!PrevDecl) 2680 return false; 2681 2682 if (!PrevDecl->hasLinkage()) 2683 return false; 2684 2685 if (Context.getLangOptions().CPlusPlus) { 2686 // C++ [basic.link]p6: 2687 // If there is a visible declaration of an entity with linkage 2688 // having the same name and type, ignoring entities declared 2689 // outside the innermost enclosing namespace scope, the block 2690 // scope declaration declares that same entity and receives the 2691 // linkage of the previous declaration. 2692 DeclContext *OuterContext = DC->getRedeclContext(); 2693 if (!OuterContext->isFunctionOrMethod()) 2694 // This rule only applies to block-scope declarations. 2695 return false; 2696 2697 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2698 if (PrevOuterContext->isRecord()) 2699 // We found a member function: ignore it. 2700 return false; 2701 2702 // Find the innermost enclosing namespace for the new and 2703 // previous declarations. 2704 OuterContext = OuterContext->getEnclosingNamespaceContext(); 2705 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 2706 2707 // The previous declaration is in a different namespace, so it 2708 // isn't the same function. 2709 if (!OuterContext->Equals(PrevOuterContext)) 2710 return false; 2711 } 2712 2713 return true; 2714} 2715 2716static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2717 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2718 if (!SS.isSet()) return; 2719 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2720 SS.getRange()); 2721} 2722 2723NamedDecl* 2724Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 2725 QualType R, TypeSourceInfo *TInfo, 2726 LookupResult &Previous, 2727 MultiTemplateParamsArg TemplateParamLists, 2728 bool &Redeclaration) { 2729 DeclarationName Name = GetNameForDeclarator(D).getName(); 2730 2731 // Check that there are no default arguments (C++ only). 2732 if (getLangOptions().CPlusPlus) 2733 CheckExtraCXXDefaultArguments(D); 2734 2735 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2736 assert(SCSpec != DeclSpec::SCS_typedef && 2737 "Parser allowed 'typedef' as storage class VarDecl."); 2738 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2739 if (SCSpec == DeclSpec::SCS_mutable) { 2740 // mutable can only appear on non-static class members, so it's always 2741 // an error here 2742 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2743 D.setInvalidType(); 2744 SC = SC_None; 2745 } 2746 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2747 VarDecl::StorageClass SCAsWritten 2748 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2749 2750 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2751 if (!II) { 2752 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2753 << Name.getAsString(); 2754 return 0; 2755 } 2756 2757 DiagnoseFunctionSpecifiers(D); 2758 2759 if (!DC->isRecord() && S->getFnParent() == 0) { 2760 // C99 6.9p2: The storage-class specifiers auto and register shall not 2761 // appear in the declaration specifiers in an external declaration. 2762 if (SC == SC_Auto || SC == SC_Register) { 2763 2764 // If this is a register variable with an asm label specified, then this 2765 // is a GNU extension. 2766 if (SC == SC_Register && D.getAsmLabel()) 2767 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2768 else 2769 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2770 D.setInvalidType(); 2771 } 2772 } 2773 if (DC->isRecord() && !CurContext->isRecord()) { 2774 // This is an out-of-line definition of a static data member. 2775 if (SC == SC_Static) { 2776 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2777 diag::err_static_out_of_line) 2778 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2779 } else if (SC == SC_None) 2780 SC = SC_Static; 2781 } 2782 if (SC == SC_Static) { 2783 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2784 if (RD->isLocalClass()) 2785 Diag(D.getIdentifierLoc(), 2786 diag::err_static_data_member_not_allowed_in_local_class) 2787 << Name << RD->getDeclName(); 2788 } 2789 } 2790 2791 // Match up the template parameter lists with the scope specifier, then 2792 // determine whether we have a template or a template specialization. 2793 bool isExplicitSpecialization = false; 2794 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2795 bool Invalid = false; 2796 if (TemplateParameterList *TemplateParams 2797 = MatchTemplateParametersToScopeSpecifier( 2798 D.getDeclSpec().getSourceRange().getBegin(), 2799 D.getCXXScopeSpec(), 2800 (TemplateParameterList**)TemplateParamLists.get(), 2801 TemplateParamLists.size(), 2802 /*never a friend*/ false, 2803 isExplicitSpecialization, 2804 Invalid)) { 2805 // All but one template parameter lists have been matching. 2806 --NumMatchedTemplateParamLists; 2807 2808 if (TemplateParams->size() > 0) { 2809 // There is no such thing as a variable template. 2810 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2811 << II 2812 << SourceRange(TemplateParams->getTemplateLoc(), 2813 TemplateParams->getRAngleLoc()); 2814 return 0; 2815 } else { 2816 // There is an extraneous 'template<>' for this variable. Complain 2817 // about it, but allow the declaration of the variable. 2818 Diag(TemplateParams->getTemplateLoc(), 2819 diag::err_template_variable_noparams) 2820 << II 2821 << SourceRange(TemplateParams->getTemplateLoc(), 2822 TemplateParams->getRAngleLoc()); 2823 2824 isExplicitSpecialization = true; 2825 } 2826 } 2827 2828 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2829 II, R, TInfo, SC, SCAsWritten); 2830 2831 if (D.isInvalidType() || Invalid) 2832 NewVD->setInvalidDecl(); 2833 2834 SetNestedNameSpecifier(NewVD, D); 2835 2836 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2837 NewVD->setTemplateParameterListsInfo(Context, 2838 NumMatchedTemplateParamLists, 2839 (TemplateParameterList**)TemplateParamLists.release()); 2840 } 2841 2842 if (D.getDeclSpec().isThreadSpecified()) { 2843 if (NewVD->hasLocalStorage()) 2844 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2845 else if (!Context.Target.isTLSSupported()) 2846 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2847 else 2848 NewVD->setThreadSpecified(true); 2849 } 2850 2851 // Set the lexical context. If the declarator has a C++ scope specifier, the 2852 // lexical context will be different from the semantic context. 2853 NewVD->setLexicalDeclContext(CurContext); 2854 2855 // Handle attributes prior to checking for duplicates in MergeVarDecl 2856 ProcessDeclAttributes(S, NewVD, D); 2857 2858 // Handle GNU asm-label extension (encoded as an attribute). 2859 if (Expr *E = (Expr*)D.getAsmLabel()) { 2860 // The parser guarantees this is a string. 2861 StringLiteral *SE = cast<StringLiteral>(E); 2862 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2863 Context, SE->getString())); 2864 } 2865 2866 // Diagnose shadowed variables before filtering for scope. 2867 if (!D.getCXXScopeSpec().isSet()) 2868 CheckShadow(S, NewVD, Previous); 2869 2870 // Don't consider existing declarations that are in a different 2871 // scope and are out-of-semantic-context declarations (if the new 2872 // declaration has linkage). 2873 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2874 2875 // Merge the decl with the existing one if appropriate. 2876 if (!Previous.empty()) { 2877 if (Previous.isSingleResult() && 2878 isa<FieldDecl>(Previous.getFoundDecl()) && 2879 D.getCXXScopeSpec().isSet()) { 2880 // The user tried to define a non-static data member 2881 // out-of-line (C++ [dcl.meaning]p1). 2882 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2883 << D.getCXXScopeSpec().getRange(); 2884 Previous.clear(); 2885 NewVD->setInvalidDecl(); 2886 } 2887 } else if (D.getCXXScopeSpec().isSet()) { 2888 // No previous declaration in the qualifying scope. 2889 Diag(D.getIdentifierLoc(), diag::err_no_member) 2890 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2891 << D.getCXXScopeSpec().getRange(); 2892 NewVD->setInvalidDecl(); 2893 } 2894 2895 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2896 2897 // This is an explicit specialization of a static data member. Check it. 2898 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2899 CheckMemberSpecialization(NewVD, Previous)) 2900 NewVD->setInvalidDecl(); 2901 2902 // attributes declared post-definition are currently ignored 2903 // FIXME: This should be handled in attribute merging, not 2904 // here. 2905 if (Previous.isSingleResult()) { 2906 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2907 if (Def && (Def = Def->getDefinition()) && 2908 Def != NewVD && D.hasAttributes()) { 2909 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2910 Diag(Def->getLocation(), diag::note_previous_definition); 2911 } 2912 } 2913 2914 // If this is a locally-scoped extern C variable, update the map of 2915 // such variables. 2916 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2917 !NewVD->isInvalidDecl()) 2918 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2919 2920 // If there's a #pragma GCC visibility in scope, and this isn't a class 2921 // member, set the visibility of this variable. 2922 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2923 AddPushedVisibilityAttribute(NewVD); 2924 2925 MarkUnusedFileScopedDecl(NewVD); 2926 2927 return NewVD; 2928} 2929 2930/// \brief Diagnose variable or built-in function shadowing. Implements 2931/// -Wshadow. 2932/// 2933/// This method is called whenever a VarDecl is added to a "useful" 2934/// scope. 2935/// 2936/// \param S the scope in which the shadowing name is being declared 2937/// \param R the lookup of the name 2938/// 2939void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2940 // Return if warning is ignored. 2941 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2942 return; 2943 2944 // Don't diagnose declarations at file scope. The scope might not 2945 // have a DeclContext if (e.g.) we're parsing a function prototype. 2946 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2947 if (NewDC && NewDC->isFileContext()) 2948 return; 2949 2950 // Only diagnose if we're shadowing an unambiguous field or variable. 2951 if (R.getResultKind() != LookupResult::Found) 2952 return; 2953 2954 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2955 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2956 return; 2957 2958 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2959 2960 // Only warn about certain kinds of shadowing for class members. 2961 if (NewDC && NewDC->isRecord()) { 2962 // In particular, don't warn about shadowing non-class members. 2963 if (!OldDC->isRecord()) 2964 return; 2965 2966 // TODO: should we warn about static data members shadowing 2967 // static data members from base classes? 2968 2969 // TODO: don't diagnose for inaccessible shadowed members. 2970 // This is hard to do perfectly because we might friend the 2971 // shadowing context, but that's just a false negative. 2972 } 2973 2974 // Determine what kind of declaration we're shadowing. 2975 unsigned Kind; 2976 if (isa<RecordDecl>(OldDC)) { 2977 if (isa<FieldDecl>(ShadowedDecl)) 2978 Kind = 3; // field 2979 else 2980 Kind = 2; // static data member 2981 } else if (OldDC->isFileContext()) 2982 Kind = 1; // global 2983 else 2984 Kind = 0; // local 2985 2986 DeclarationName Name = R.getLookupName(); 2987 2988 // Emit warning and note. 2989 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2990 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2991} 2992 2993/// \brief Check -Wshadow without the advantage of a previous lookup. 2994void Sema::CheckShadow(Scope *S, VarDecl *D) { 2995 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2996 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2997 LookupName(R, S); 2998 CheckShadow(S, D, R); 2999} 3000 3001/// \brief Perform semantic checking on a newly-created variable 3002/// declaration. 3003/// 3004/// This routine performs all of the type-checking required for a 3005/// variable declaration once it has been built. It is used both to 3006/// check variables after they have been parsed and their declarators 3007/// have been translated into a declaration, and to check variables 3008/// that have been instantiated from a template. 3009/// 3010/// Sets NewVD->isInvalidDecl() if an error was encountered. 3011void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3012 LookupResult &Previous, 3013 bool &Redeclaration) { 3014 // If the decl is already known invalid, don't check it. 3015 if (NewVD->isInvalidDecl()) 3016 return; 3017 3018 QualType T = NewVD->getType(); 3019 3020 if (T->isObjCObjectType()) { 3021 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3022 return NewVD->setInvalidDecl(); 3023 } 3024 3025 // Emit an error if an address space was applied to decl with local storage. 3026 // This includes arrays of objects with address space qualifiers, but not 3027 // automatic variables that point to other address spaces. 3028 // ISO/IEC TR 18037 S5.1.2 3029 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3030 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3031 return NewVD->setInvalidDecl(); 3032 } 3033 3034 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3035 && !NewVD->hasAttr<BlocksAttr>()) 3036 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3037 3038 bool isVM = T->isVariablyModifiedType(); 3039 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3040 NewVD->hasAttr<BlocksAttr>()) 3041 getCurFunction()->setHasBranchProtectedScope(); 3042 3043 if ((isVM && NewVD->hasLinkage()) || 3044 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3045 bool SizeIsNegative; 3046 llvm::APSInt Oversized; 3047 QualType FixedTy = 3048 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3049 Oversized); 3050 3051 if (FixedTy.isNull() && T->isVariableArrayType()) { 3052 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3053 // FIXME: This won't give the correct result for 3054 // int a[10][n]; 3055 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3056 3057 if (NewVD->isFileVarDecl()) 3058 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3059 << SizeRange; 3060 else if (NewVD->getStorageClass() == SC_Static) 3061 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3062 << SizeRange; 3063 else 3064 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3065 << SizeRange; 3066 return NewVD->setInvalidDecl(); 3067 } 3068 3069 if (FixedTy.isNull()) { 3070 if (NewVD->isFileVarDecl()) 3071 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3072 else 3073 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3074 return NewVD->setInvalidDecl(); 3075 } 3076 3077 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3078 NewVD->setType(FixedTy); 3079 } 3080 3081 if (Previous.empty() && NewVD->isExternC()) { 3082 // Since we did not find anything by this name and we're declaring 3083 // an extern "C" variable, look for a non-visible extern "C" 3084 // declaration with the same name. 3085 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3086 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3087 if (Pos != LocallyScopedExternalDecls.end()) 3088 Previous.addDecl(Pos->second); 3089 } 3090 3091 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3092 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3093 << T; 3094 return NewVD->setInvalidDecl(); 3095 } 3096 3097 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3098 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3099 return NewVD->setInvalidDecl(); 3100 } 3101 3102 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3103 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3104 return NewVD->setInvalidDecl(); 3105 } 3106 3107 // Function pointers and references cannot have qualified function type, only 3108 // function pointer-to-members can do that. 3109 QualType Pointee; 3110 unsigned PtrOrRef = 0; 3111 if (const PointerType *Ptr = T->getAs<PointerType>()) 3112 Pointee = Ptr->getPointeeType(); 3113 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3114 Pointee = Ref->getPointeeType(); 3115 PtrOrRef = 1; 3116 } 3117 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3118 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3119 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3120 << PtrOrRef; 3121 return NewVD->setInvalidDecl(); 3122 } 3123 3124 if (!Previous.empty()) { 3125 Redeclaration = true; 3126 MergeVarDecl(NewVD, Previous); 3127 } 3128} 3129 3130/// \brief Data used with FindOverriddenMethod 3131struct FindOverriddenMethodData { 3132 Sema *S; 3133 CXXMethodDecl *Method; 3134}; 3135 3136/// \brief Member lookup function that determines whether a given C++ 3137/// method overrides a method in a base class, to be used with 3138/// CXXRecordDecl::lookupInBases(). 3139static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3140 CXXBasePath &Path, 3141 void *UserData) { 3142 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3143 3144 FindOverriddenMethodData *Data 3145 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3146 3147 DeclarationName Name = Data->Method->getDeclName(); 3148 3149 // FIXME: Do we care about other names here too? 3150 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3151 // We really want to find the base class destructor here. 3152 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3153 CanQualType CT = Data->S->Context.getCanonicalType(T); 3154 3155 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3156 } 3157 3158 for (Path.Decls = BaseRecord->lookup(Name); 3159 Path.Decls.first != Path.Decls.second; 3160 ++Path.Decls.first) { 3161 NamedDecl *D = *Path.Decls.first; 3162 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3163 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3164 return true; 3165 } 3166 } 3167 3168 return false; 3169} 3170 3171/// AddOverriddenMethods - See if a method overrides any in the base classes, 3172/// and if so, check that it's a valid override and remember it. 3173bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3174 // Look for virtual methods in base classes that this method might override. 3175 CXXBasePaths Paths; 3176 FindOverriddenMethodData Data; 3177 Data.Method = MD; 3178 Data.S = this; 3179 bool AddedAny = false; 3180 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3181 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3182 E = Paths.found_decls_end(); I != E; ++I) { 3183 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3184 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3185 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3186 !CheckOverridingFunctionAttributes(MD, OldMD)) { 3187 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3188 AddedAny = true; 3189 } 3190 } 3191 } 3192 } 3193 3194 return AddedAny; 3195} 3196 3197static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3198 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3199 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3200 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3201 assert(!Prev.isAmbiguous() && 3202 "Cannot have an ambiguity in previous-declaration lookup"); 3203 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3204 Func != FuncEnd; ++Func) { 3205 if (isa<FunctionDecl>(*Func) && 3206 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3207 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3208 } 3209} 3210 3211NamedDecl* 3212Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3213 QualType R, TypeSourceInfo *TInfo, 3214 LookupResult &Previous, 3215 MultiTemplateParamsArg TemplateParamLists, 3216 bool IsFunctionDefinition, bool &Redeclaration) { 3217 assert(R.getTypePtr()->isFunctionType()); 3218 3219 // TODO: consider using NameInfo for diagnostic. 3220 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3221 DeclarationName Name = NameInfo.getName(); 3222 FunctionDecl::StorageClass SC = SC_None; 3223 switch (D.getDeclSpec().getStorageClassSpec()) { 3224 default: assert(0 && "Unknown storage class!"); 3225 case DeclSpec::SCS_auto: 3226 case DeclSpec::SCS_register: 3227 case DeclSpec::SCS_mutable: 3228 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3229 diag::err_typecheck_sclass_func); 3230 D.setInvalidType(); 3231 break; 3232 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3233 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3234 case DeclSpec::SCS_static: { 3235 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3236 // C99 6.7.1p5: 3237 // The declaration of an identifier for a function that has 3238 // block scope shall have no explicit storage-class specifier 3239 // other than extern 3240 // See also (C++ [dcl.stc]p4). 3241 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3242 diag::err_static_block_func); 3243 SC = SC_None; 3244 } else 3245 SC = SC_Static; 3246 break; 3247 } 3248 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3249 } 3250 3251 if (D.getDeclSpec().isThreadSpecified()) 3252 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3253 3254 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3255 bool isInline = D.getDeclSpec().isInlineSpecified(); 3256 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3257 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3258 3259 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3260 FunctionDecl::StorageClass SCAsWritten 3261 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3262 3263 // Check that the return type is not an abstract class type. 3264 // For record types, this is done by the AbstractClassUsageDiagnoser once 3265 // the class has been completely parsed. 3266 if (!DC->isRecord() && 3267 RequireNonAbstractType(D.getIdentifierLoc(), 3268 R->getAs<FunctionType>()->getResultType(), 3269 diag::err_abstract_type_in_decl, 3270 AbstractReturnType)) 3271 D.setInvalidType(); 3272 3273 // Do not allow returning a objc interface by-value. 3274 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3275 Diag(D.getIdentifierLoc(), 3276 diag::err_object_cannot_be_passed_returned_by_value) << 0 3277 << R->getAs<FunctionType>()->getResultType(); 3278 D.setInvalidType(); 3279 } 3280 3281 bool isVirtualOkay = false; 3282 FunctionDecl *NewFD; 3283 3284 if (isFriend) { 3285 // C++ [class.friend]p5 3286 // A function can be defined in a friend declaration of a 3287 // class . . . . Such a function is implicitly inline. 3288 isInline |= IsFunctionDefinition; 3289 } 3290 3291 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3292 // This is a C++ constructor declaration. 3293 assert(DC->isRecord() && 3294 "Constructors can only be declared in a member context"); 3295 3296 R = CheckConstructorDeclarator(D, R, SC); 3297 3298 // Create the new declaration 3299 NewFD = CXXConstructorDecl::Create(Context, 3300 cast<CXXRecordDecl>(DC), 3301 NameInfo, R, TInfo, 3302 isExplicit, isInline, 3303 /*isImplicitlyDeclared=*/false); 3304 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3305 // This is a C++ destructor declaration. 3306 if (DC->isRecord()) { 3307 R = CheckDestructorDeclarator(D, R, SC); 3308 3309 NewFD = CXXDestructorDecl::Create(Context, 3310 cast<CXXRecordDecl>(DC), 3311 NameInfo, R, 3312 isInline, 3313 /*isImplicitlyDeclared=*/false); 3314 NewFD->setTypeSourceInfo(TInfo); 3315 3316 isVirtualOkay = true; 3317 } else { 3318 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3319 3320 // Create a FunctionDecl to satisfy the function definition parsing 3321 // code path. 3322 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3323 Name, R, TInfo, SC, SCAsWritten, isInline, 3324 /*hasPrototype=*/true); 3325 D.setInvalidType(); 3326 } 3327 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3328 if (!DC->isRecord()) { 3329 Diag(D.getIdentifierLoc(), 3330 diag::err_conv_function_not_member); 3331 return 0; 3332 } 3333 3334 CheckConversionDeclarator(D, R, SC); 3335 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3336 NameInfo, R, TInfo, 3337 isInline, isExplicit); 3338 3339 isVirtualOkay = true; 3340 } else if (DC->isRecord()) { 3341 // If the of the function is the same as the name of the record, then this 3342 // must be an invalid constructor that has a return type. 3343 // (The parser checks for a return type and makes the declarator a 3344 // constructor if it has no return type). 3345 // must have an invalid constructor that has a return type 3346 if (Name.getAsIdentifierInfo() && 3347 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3348 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3349 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3350 << SourceRange(D.getIdentifierLoc()); 3351 return 0; 3352 } 3353 3354 bool isStatic = SC == SC_Static; 3355 3356 // [class.free]p1: 3357 // Any allocation function for a class T is a static member 3358 // (even if not explicitly declared static). 3359 if (Name.getCXXOverloadedOperator() == OO_New || 3360 Name.getCXXOverloadedOperator() == OO_Array_New) 3361 isStatic = true; 3362 3363 // [class.free]p6 Any deallocation function for a class X is a static member 3364 // (even if not explicitly declared static). 3365 if (Name.getCXXOverloadedOperator() == OO_Delete || 3366 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3367 isStatic = true; 3368 3369 // This is a C++ method declaration. 3370 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3371 NameInfo, R, TInfo, 3372 isStatic, SCAsWritten, isInline); 3373 3374 isVirtualOkay = !isStatic; 3375 } else { 3376 // Determine whether the function was written with a 3377 // prototype. This true when: 3378 // - we're in C++ (where every function has a prototype), 3379 // - there is a prototype in the declarator, or 3380 // - the type R of the function is some kind of typedef or other reference 3381 // to a type name (which eventually refers to a function type). 3382 bool HasPrototype = 3383 getLangOptions().CPlusPlus || 3384 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3385 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3386 3387 NewFD = FunctionDecl::Create(Context, DC, 3388 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3389 HasPrototype); 3390 } 3391 3392 if (D.isInvalidType()) 3393 NewFD->setInvalidDecl(); 3394 3395 SetNestedNameSpecifier(NewFD, D); 3396 3397 // Set the lexical context. If the declarator has a C++ 3398 // scope specifier, or is the object of a friend declaration, the 3399 // lexical context will be different from the semantic context. 3400 NewFD->setLexicalDeclContext(CurContext); 3401 3402 // Match up the template parameter lists with the scope specifier, then 3403 // determine whether we have a template or a template specialization. 3404 FunctionTemplateDecl *FunctionTemplate = 0; 3405 bool isExplicitSpecialization = false; 3406 bool isFunctionTemplateSpecialization = false; 3407 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3408 bool Invalid = false; 3409 if (TemplateParameterList *TemplateParams 3410 = MatchTemplateParametersToScopeSpecifier( 3411 D.getDeclSpec().getSourceRange().getBegin(), 3412 D.getCXXScopeSpec(), 3413 TemplateParamLists.get(), 3414 TemplateParamLists.size(), 3415 isFriend, 3416 isExplicitSpecialization, 3417 Invalid)) { 3418 // All but one template parameter lists have been matching. 3419 --NumMatchedTemplateParamLists; 3420 3421 if (TemplateParams->size() > 0) { 3422 // This is a function template 3423 3424 // Check that we can declare a template here. 3425 if (CheckTemplateDeclScope(S, TemplateParams)) 3426 return 0; 3427 3428 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3429 NewFD->getLocation(), 3430 Name, TemplateParams, 3431 NewFD); 3432 FunctionTemplate->setLexicalDeclContext(CurContext); 3433 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3434 } else { 3435 // This is a function template specialization. 3436 isFunctionTemplateSpecialization = true; 3437 3438 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3439 if (isFriend && isFunctionTemplateSpecialization) { 3440 // We want to remove the "template<>", found here. 3441 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3442 3443 // If we remove the template<> and the name is not a 3444 // template-id, we're actually silently creating a problem: 3445 // the friend declaration will refer to an untemplated decl, 3446 // and clearly the user wants a template specialization. So 3447 // we need to insert '<>' after the name. 3448 SourceLocation InsertLoc; 3449 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3450 InsertLoc = D.getName().getSourceRange().getEnd(); 3451 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3452 } 3453 3454 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3455 << Name << RemoveRange 3456 << FixItHint::CreateRemoval(RemoveRange) 3457 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3458 } 3459 } 3460 } 3461 3462 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3463 NewFD->setTemplateParameterListsInfo(Context, 3464 NumMatchedTemplateParamLists, 3465 TemplateParamLists.release()); 3466 } 3467 3468 if (Invalid) { 3469 NewFD->setInvalidDecl(); 3470 if (FunctionTemplate) 3471 FunctionTemplate->setInvalidDecl(); 3472 } 3473 3474 // C++ [dcl.fct.spec]p5: 3475 // The virtual specifier shall only be used in declarations of 3476 // nonstatic class member functions that appear within a 3477 // member-specification of a class declaration; see 10.3. 3478 // 3479 if (isVirtual && !NewFD->isInvalidDecl()) { 3480 if (!isVirtualOkay) { 3481 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3482 diag::err_virtual_non_function); 3483 } else if (!CurContext->isRecord()) { 3484 // 'virtual' was specified outside of the class. 3485 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3486 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3487 } else { 3488 // Okay: Add virtual to the method. 3489 NewFD->setVirtualAsWritten(true); 3490 } 3491 } 3492 3493 // C++ [dcl.fct.spec]p3: 3494 // The inline specifier shall not appear on a block scope function declaration. 3495 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3496 if (CurContext->isFunctionOrMethod()) { 3497 // 'inline' is not allowed on block scope function declaration. 3498 Diag(D.getDeclSpec().getInlineSpecLoc(), 3499 diag::err_inline_declaration_block_scope) << Name 3500 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3501 } 3502 } 3503 3504 // C++ [dcl.fct.spec]p6: 3505 // The explicit specifier shall be used only in the declaration of a 3506 // constructor or conversion function within its class definition; see 12.3.1 3507 // and 12.3.2. 3508 if (isExplicit && !NewFD->isInvalidDecl()) { 3509 if (!CurContext->isRecord()) { 3510 // 'explicit' was specified outside of the class. 3511 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3512 diag::err_explicit_out_of_class) 3513 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3514 } else if (!isa<CXXConstructorDecl>(NewFD) && 3515 !isa<CXXConversionDecl>(NewFD)) { 3516 // 'explicit' was specified on a function that wasn't a constructor 3517 // or conversion function. 3518 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3519 diag::err_explicit_non_ctor_or_conv_function) 3520 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3521 } 3522 } 3523 3524 // Filter out previous declarations that don't match the scope. 3525 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3526 3527 if (isFriend) { 3528 // For now, claim that the objects have no previous declaration. 3529 if (FunctionTemplate) { 3530 FunctionTemplate->setObjectOfFriendDecl(false); 3531 FunctionTemplate->setAccess(AS_public); 3532 } 3533 NewFD->setObjectOfFriendDecl(false); 3534 NewFD->setAccess(AS_public); 3535 } 3536 3537 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3538 !CurContext->isRecord()) { 3539 // C++ [class.static]p1: 3540 // A data or function member of a class may be declared static 3541 // in a class definition, in which case it is a static member of 3542 // the class. 3543 3544 // Complain about the 'static' specifier if it's on an out-of-line 3545 // member function definition. 3546 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3547 diag::err_static_out_of_line) 3548 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3549 } 3550 3551 // Handle GNU asm-label extension (encoded as an attribute). 3552 if (Expr *E = (Expr*) D.getAsmLabel()) { 3553 // The parser guarantees this is a string. 3554 StringLiteral *SE = cast<StringLiteral>(E); 3555 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3556 SE->getString())); 3557 } 3558 3559 // Copy the parameter declarations from the declarator D to the function 3560 // declaration NewFD, if they are available. First scavenge them into Params. 3561 llvm::SmallVector<ParmVarDecl*, 16> Params; 3562 if (D.getNumTypeObjects() > 0) { 3563 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3564 3565 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3566 // function that takes no arguments, not a function that takes a 3567 // single void argument. 3568 // We let through "const void" here because Sema::GetTypeForDeclarator 3569 // already checks for that case. 3570 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3571 FTI.ArgInfo[0].Param && 3572 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3573 // Empty arg list, don't push any params. 3574 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3575 3576 // In C++, the empty parameter-type-list must be spelled "void"; a 3577 // typedef of void is not permitted. 3578 if (getLangOptions().CPlusPlus && 3579 Param->getType().getUnqualifiedType() != Context.VoidTy) 3580 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3581 // FIXME: Leaks decl? 3582 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3583 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3584 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3585 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3586 Param->setDeclContext(NewFD); 3587 Params.push_back(Param); 3588 3589 if (Param->isInvalidDecl()) 3590 NewFD->setInvalidDecl(); 3591 } 3592 } 3593 3594 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3595 // When we're declaring a function with a typedef, typeof, etc as in the 3596 // following example, we'll need to synthesize (unnamed) 3597 // parameters for use in the declaration. 3598 // 3599 // @code 3600 // typedef void fn(int); 3601 // fn f; 3602 // @endcode 3603 3604 // Synthesize a parameter for each argument type. 3605 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3606 AE = FT->arg_type_end(); AI != AE; ++AI) { 3607 ParmVarDecl *Param = 3608 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3609 Params.push_back(Param); 3610 } 3611 } else { 3612 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3613 "Should not need args for typedef of non-prototype fn"); 3614 } 3615 // Finally, we know we have the right number of parameters, install them. 3616 NewFD->setParams(Params.data(), Params.size()); 3617 3618 // If the declarator is a template-id, translate the parser's template 3619 // argument list into our AST format. 3620 bool HasExplicitTemplateArgs = false; 3621 TemplateArgumentListInfo TemplateArgs; 3622 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3623 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3624 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3625 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3626 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3627 TemplateId->getTemplateArgs(), 3628 TemplateId->NumArgs); 3629 translateTemplateArguments(TemplateArgsPtr, 3630 TemplateArgs); 3631 TemplateArgsPtr.release(); 3632 3633 HasExplicitTemplateArgs = true; 3634 3635 if (FunctionTemplate) { 3636 // FIXME: Diagnose function template with explicit template 3637 // arguments. 3638 HasExplicitTemplateArgs = false; 3639 } else if (!isFunctionTemplateSpecialization && 3640 !D.getDeclSpec().isFriendSpecified()) { 3641 // We have encountered something that the user meant to be a 3642 // specialization (because it has explicitly-specified template 3643 // arguments) but that was not introduced with a "template<>" (or had 3644 // too few of them). 3645 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3646 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3647 << FixItHint::CreateInsertion( 3648 D.getDeclSpec().getSourceRange().getBegin(), 3649 "template<> "); 3650 isFunctionTemplateSpecialization = true; 3651 } else { 3652 // "friend void foo<>(int);" is an implicit specialization decl. 3653 isFunctionTemplateSpecialization = true; 3654 } 3655 } else if (isFriend && isFunctionTemplateSpecialization) { 3656 // This combination is only possible in a recovery case; the user 3657 // wrote something like: 3658 // template <> friend void foo(int); 3659 // which we're recovering from as if the user had written: 3660 // friend void foo<>(int); 3661 // Go ahead and fake up a template id. 3662 HasExplicitTemplateArgs = true; 3663 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3664 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3665 } 3666 3667 // If it's a friend (and only if it's a friend), it's possible 3668 // that either the specialized function type or the specialized 3669 // template is dependent, and therefore matching will fail. In 3670 // this case, don't check the specialization yet. 3671 if (isFunctionTemplateSpecialization && isFriend && 3672 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3673 assert(HasExplicitTemplateArgs && 3674 "friend function specialization without template args"); 3675 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3676 Previous)) 3677 NewFD->setInvalidDecl(); 3678 } else if (isFunctionTemplateSpecialization) { 3679 if (CheckFunctionTemplateSpecialization(NewFD, 3680 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3681 Previous)) 3682 NewFD->setInvalidDecl(); 3683 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3684 if (CheckMemberSpecialization(NewFD, Previous)) 3685 NewFD->setInvalidDecl(); 3686 } 3687 3688 // Perform semantic checking on the function declaration. 3689 bool OverloadableAttrRequired = false; // FIXME: HACK! 3690 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3691 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3692 3693 assert((NewFD->isInvalidDecl() || !Redeclaration || 3694 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3695 "previous declaration set still overloaded"); 3696 3697 NamedDecl *PrincipalDecl = (FunctionTemplate 3698 ? cast<NamedDecl>(FunctionTemplate) 3699 : NewFD); 3700 3701 if (isFriend && Redeclaration) { 3702 AccessSpecifier Access = AS_public; 3703 if (!NewFD->isInvalidDecl()) 3704 Access = NewFD->getPreviousDeclaration()->getAccess(); 3705 3706 NewFD->setAccess(Access); 3707 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3708 3709 PrincipalDecl->setObjectOfFriendDecl(true); 3710 } 3711 3712 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3713 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3714 PrincipalDecl->setNonMemberOperator(); 3715 3716 // If we have a function template, check the template parameter 3717 // list. This will check and merge default template arguments. 3718 if (FunctionTemplate) { 3719 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3720 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3721 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3722 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3723 : TPC_FunctionTemplate); 3724 } 3725 3726 if (NewFD->isInvalidDecl()) { 3727 // Ignore all the rest of this. 3728 } else if (!Redeclaration) { 3729 // Fake up an access specifier if it's supposed to be a class member. 3730 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 3731 NewFD->setAccess(AS_public); 3732 3733 // Qualified decls generally require a previous declaration. 3734 if (D.getCXXScopeSpec().isSet()) { 3735 // ...with the major exception of templated-scope or 3736 // dependent-scope friend declarations. 3737 3738 // TODO: we currently also suppress this check in dependent 3739 // contexts because (1) the parameter depth will be off when 3740 // matching friend templates and (2) we might actually be 3741 // selecting a friend based on a dependent factor. But there 3742 // are situations where these conditions don't apply and we 3743 // can actually do this check immediately. 3744 if (isFriend && 3745 (NumMatchedTemplateParamLists || 3746 D.getCXXScopeSpec().getScopeRep()->isDependent() || 3747 CurContext->isDependentContext())) { 3748 // ignore these 3749 } else { 3750 // The user tried to provide an out-of-line definition for a 3751 // function that is a member of a class or namespace, but there 3752 // was no such member function declared (C++ [class.mfct]p2, 3753 // C++ [namespace.memdef]p2). For example: 3754 // 3755 // class X { 3756 // void f() const; 3757 // }; 3758 // 3759 // void X::f() { } // ill-formed 3760 // 3761 // Complain about this problem, and attempt to suggest close 3762 // matches (e.g., those that differ only in cv-qualifiers and 3763 // whether the parameter types are references). 3764 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3765 << Name << DC << D.getCXXScopeSpec().getRange(); 3766 NewFD->setInvalidDecl(); 3767 3768 DiagnoseInvalidRedeclaration(*this, NewFD); 3769 } 3770 3771 // Unqualified local friend declarations are required to resolve 3772 // to something. 3773 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 3774 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 3775 NewFD->setInvalidDecl(); 3776 DiagnoseInvalidRedeclaration(*this, NewFD); 3777 } 3778 3779 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 3780 !isFriend && !isFunctionTemplateSpecialization && 3781 !isExplicitSpecialization) { 3782 // An out-of-line member function declaration must also be a 3783 // definition (C++ [dcl.meaning]p1). 3784 // Note that this is not the case for explicit specializations of 3785 // function templates or member functions of class templates, per 3786 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3787 // for compatibility with old SWIG code which likes to generate them. 3788 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3789 << D.getCXXScopeSpec().getRange(); 3790 } 3791 3792 // Handle attributes. We need to have merged decls when handling attributes 3793 // (for example to check for conflicts, etc). 3794 // FIXME: This needs to happen before we merge declarations. Then, 3795 // let attribute merging cope with attribute conflicts. 3796 ProcessDeclAttributes(S, NewFD, D); 3797 3798 // attributes declared post-definition are currently ignored 3799 // FIXME: This should happen during attribute merging 3800 if (Redeclaration && Previous.isSingleResult()) { 3801 const FunctionDecl *Def; 3802 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3803 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3804 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3805 Diag(Def->getLocation(), diag::note_previous_definition); 3806 } 3807 } 3808 3809 AddKnownFunctionAttributes(NewFD); 3810 3811 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3812 // If a function name is overloadable in C, then every function 3813 // with that name must be marked "overloadable". 3814 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3815 << Redeclaration << NewFD; 3816 if (!Previous.empty()) 3817 Diag(Previous.getRepresentativeDecl()->getLocation(), 3818 diag::note_attribute_overloadable_prev_overload); 3819 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3820 } 3821 3822 if (NewFD->hasAttr<OverloadableAttr>() && 3823 !NewFD->getType()->getAs<FunctionProtoType>()) { 3824 Diag(NewFD->getLocation(), 3825 diag::err_attribute_overloadable_no_prototype) 3826 << NewFD; 3827 3828 // Turn this into a variadic function with no parameters. 3829 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3830 QualType R = Context.getFunctionType(FT->getResultType(), 3831 0, 0, true, 0, false, false, 0, 0, 3832 FT->getExtInfo()); 3833 NewFD->setType(R); 3834 } 3835 3836 // If there's a #pragma GCC visibility in scope, and this isn't a class 3837 // member, set the visibility of this function. 3838 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3839 AddPushedVisibilityAttribute(NewFD); 3840 3841 // If this is a locally-scoped extern C function, update the 3842 // map of such names. 3843 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3844 && !NewFD->isInvalidDecl()) 3845 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3846 3847 // Set this FunctionDecl's range up to the right paren. 3848 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3849 3850 if (FunctionTemplate && NewFD->isInvalidDecl()) 3851 FunctionTemplate->setInvalidDecl(); 3852 3853 if (FunctionTemplate) 3854 return FunctionTemplate; 3855 3856 MarkUnusedFileScopedDecl(NewFD); 3857 3858 return NewFD; 3859} 3860 3861/// \brief Perform semantic checking of a new function declaration. 3862/// 3863/// Performs semantic analysis of the new function declaration 3864/// NewFD. This routine performs all semantic checking that does not 3865/// require the actual declarator involved in the declaration, and is 3866/// used both for the declaration of functions as they are parsed 3867/// (called via ActOnDeclarator) and for the declaration of functions 3868/// that have been instantiated via C++ template instantiation (called 3869/// via InstantiateDecl). 3870/// 3871/// \param IsExplicitSpecialiation whether this new function declaration is 3872/// an explicit specialization of the previous declaration. 3873/// 3874/// This sets NewFD->isInvalidDecl() to true if there was an error. 3875void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3876 LookupResult &Previous, 3877 bool IsExplicitSpecialization, 3878 bool &Redeclaration, 3879 bool &OverloadableAttrRequired) { 3880 // If NewFD is already known erroneous, don't do any of this checking. 3881 if (NewFD->isInvalidDecl()) { 3882 // If this is a class member, mark the class invalid immediately. 3883 // This avoids some consistency errors later. 3884 if (isa<CXXMethodDecl>(NewFD)) 3885 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3886 3887 return; 3888 } 3889 3890 if (NewFD->getResultType()->isVariablyModifiedType()) { 3891 // Functions returning a variably modified type violate C99 6.7.5.2p2 3892 // because all functions have linkage. 3893 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3894 return NewFD->setInvalidDecl(); 3895 } 3896 3897 if (NewFD->isMain()) 3898 CheckMain(NewFD); 3899 3900 // Check for a previous declaration of this name. 3901 if (Previous.empty() && NewFD->isExternC()) { 3902 // Since we did not find anything by this name and we're declaring 3903 // an extern "C" function, look for a non-visible extern "C" 3904 // declaration with the same name. 3905 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3906 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3907 if (Pos != LocallyScopedExternalDecls.end()) 3908 Previous.addDecl(Pos->second); 3909 } 3910 3911 // Merge or overload the declaration with an existing declaration of 3912 // the same name, if appropriate. 3913 if (!Previous.empty()) { 3914 // Determine whether NewFD is an overload of PrevDecl or 3915 // a declaration that requires merging. If it's an overload, 3916 // there's no more work to do here; we'll just add the new 3917 // function to the scope. 3918 3919 NamedDecl *OldDecl = 0; 3920 if (!AllowOverloadingOfFunction(Previous, Context)) { 3921 Redeclaration = true; 3922 OldDecl = Previous.getFoundDecl(); 3923 } else { 3924 if (!getLangOptions().CPlusPlus) 3925 OverloadableAttrRequired = true; 3926 3927 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3928 /*NewIsUsingDecl*/ false)) { 3929 case Ovl_Match: 3930 Redeclaration = true; 3931 break; 3932 3933 case Ovl_NonFunction: 3934 Redeclaration = true; 3935 break; 3936 3937 case Ovl_Overload: 3938 Redeclaration = false; 3939 break; 3940 } 3941 } 3942 3943 if (Redeclaration) { 3944 // NewFD and OldDecl represent declarations that need to be 3945 // merged. 3946 if (MergeFunctionDecl(NewFD, OldDecl)) 3947 return NewFD->setInvalidDecl(); 3948 3949 Previous.clear(); 3950 Previous.addDecl(OldDecl); 3951 3952 if (FunctionTemplateDecl *OldTemplateDecl 3953 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3954 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3955 FunctionTemplateDecl *NewTemplateDecl 3956 = NewFD->getDescribedFunctionTemplate(); 3957 assert(NewTemplateDecl && "Template/non-template mismatch"); 3958 if (CXXMethodDecl *Method 3959 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3960 Method->setAccess(OldTemplateDecl->getAccess()); 3961 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3962 } 3963 3964 // If this is an explicit specialization of a member that is a function 3965 // template, mark it as a member specialization. 3966 if (IsExplicitSpecialization && 3967 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3968 NewTemplateDecl->setMemberSpecialization(); 3969 assert(OldTemplateDecl->isMemberSpecialization()); 3970 } 3971 } else { 3972 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3973 NewFD->setAccess(OldDecl->getAccess()); 3974 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3975 } 3976 } 3977 } 3978 3979 // Semantic checking for this function declaration (in isolation). 3980 if (getLangOptions().CPlusPlus) { 3981 // C++-specific checks. 3982 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3983 CheckConstructor(Constructor); 3984 } else if (CXXDestructorDecl *Destructor = 3985 dyn_cast<CXXDestructorDecl>(NewFD)) { 3986 CXXRecordDecl *Record = Destructor->getParent(); 3987 QualType ClassType = Context.getTypeDeclType(Record); 3988 3989 // FIXME: Shouldn't we be able to perform this check even when the class 3990 // type is dependent? Both gcc and edg can handle that. 3991 if (!ClassType->isDependentType()) { 3992 DeclarationName Name 3993 = Context.DeclarationNames.getCXXDestructorName( 3994 Context.getCanonicalType(ClassType)); 3995 if (NewFD->getDeclName() != Name) { 3996 Diag(NewFD->getLocation(), diag::err_destructor_name); 3997 return NewFD->setInvalidDecl(); 3998 } 3999 } 4000 } else if (CXXConversionDecl *Conversion 4001 = dyn_cast<CXXConversionDecl>(NewFD)) { 4002 ActOnConversionDeclarator(Conversion); 4003 } 4004 4005 // Find any virtual functions that this function overrides. 4006 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4007 if (!Method->isFunctionTemplateSpecialization() && 4008 !Method->getDescribedFunctionTemplate()) { 4009 if (AddOverriddenMethods(Method->getParent(), Method)) { 4010 // If the function was marked as "static", we have a problem. 4011 if (NewFD->getStorageClass() == SC_Static) { 4012 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4013 << NewFD->getDeclName(); 4014 for (CXXMethodDecl::method_iterator 4015 Overridden = Method->begin_overridden_methods(), 4016 OverriddenEnd = Method->end_overridden_methods(); 4017 Overridden != OverriddenEnd; 4018 ++Overridden) { 4019 Diag((*Overridden)->getLocation(), 4020 diag::note_overridden_virtual_function); 4021 } 4022 } 4023 } 4024 } 4025 } 4026 4027 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4028 if (NewFD->isOverloadedOperator() && 4029 CheckOverloadedOperatorDeclaration(NewFD)) 4030 return NewFD->setInvalidDecl(); 4031 4032 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4033 if (NewFD->getLiteralIdentifier() && 4034 CheckLiteralOperatorDeclaration(NewFD)) 4035 return NewFD->setInvalidDecl(); 4036 4037 // In C++, check default arguments now that we have merged decls. Unless 4038 // the lexical context is the class, because in this case this is done 4039 // during delayed parsing anyway. 4040 if (!CurContext->isRecord()) 4041 CheckCXXDefaultArguments(NewFD); 4042 } 4043} 4044 4045void Sema::CheckMain(FunctionDecl* FD) { 4046 // C++ [basic.start.main]p3: A program that declares main to be inline 4047 // or static is ill-formed. 4048 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4049 // shall not appear in a declaration of main. 4050 // static main is not an error under C99, but we should warn about it. 4051 bool isInline = FD->isInlineSpecified(); 4052 bool isStatic = FD->getStorageClass() == SC_Static; 4053 if (isInline || isStatic) { 4054 unsigned diagID = diag::warn_unusual_main_decl; 4055 if (isInline || getLangOptions().CPlusPlus) 4056 diagID = diag::err_unusual_main_decl; 4057 4058 int which = isStatic + (isInline << 1) - 1; 4059 Diag(FD->getLocation(), diagID) << which; 4060 } 4061 4062 QualType T = FD->getType(); 4063 assert(T->isFunctionType() && "function decl is not of function type"); 4064 const FunctionType* FT = T->getAs<FunctionType>(); 4065 4066 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4067 TypeSourceInfo *TSI = FD->getTypeSourceInfo(); 4068 TypeLoc TL = TSI->getTypeLoc(); 4069 const SemaDiagnosticBuilder& D = Diag(FD->getTypeSpecStartLoc(), 4070 diag::err_main_returns_nonint); 4071 if (FunctionTypeLoc* PTL = dyn_cast<FunctionTypeLoc>(&TL)) { 4072 D << FixItHint::CreateReplacement(PTL->getResultLoc().getSourceRange(), 4073 "int"); 4074 } 4075 FD->setInvalidDecl(true); 4076 } 4077 4078 // Treat protoless main() as nullary. 4079 if (isa<FunctionNoProtoType>(FT)) return; 4080 4081 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4082 unsigned nparams = FTP->getNumArgs(); 4083 assert(FD->getNumParams() == nparams); 4084 4085 bool HasExtraParameters = (nparams > 3); 4086 4087 // Darwin passes an undocumented fourth argument of type char**. If 4088 // other platforms start sprouting these, the logic below will start 4089 // getting shifty. 4090 if (nparams == 4 && 4091 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4092 HasExtraParameters = false; 4093 4094 if (HasExtraParameters) { 4095 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4096 FD->setInvalidDecl(true); 4097 nparams = 3; 4098 } 4099 4100 // FIXME: a lot of the following diagnostics would be improved 4101 // if we had some location information about types. 4102 4103 QualType CharPP = 4104 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4105 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4106 4107 for (unsigned i = 0; i < nparams; ++i) { 4108 QualType AT = FTP->getArgType(i); 4109 4110 bool mismatch = true; 4111 4112 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4113 mismatch = false; 4114 else if (Expected[i] == CharPP) { 4115 // As an extension, the following forms are okay: 4116 // char const ** 4117 // char const * const * 4118 // char * const * 4119 4120 QualifierCollector qs; 4121 const PointerType* PT; 4122 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4123 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4124 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4125 qs.removeConst(); 4126 mismatch = !qs.empty(); 4127 } 4128 } 4129 4130 if (mismatch) { 4131 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4132 // TODO: suggest replacing given type with expected type 4133 FD->setInvalidDecl(true); 4134 } 4135 } 4136 4137 if (nparams == 1 && !FD->isInvalidDecl()) { 4138 Diag(FD->getLocation(), diag::warn_main_one_arg); 4139 } 4140} 4141 4142bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4143 // FIXME: Need strict checking. In C89, we need to check for 4144 // any assignment, increment, decrement, function-calls, or 4145 // commas outside of a sizeof. In C99, it's the same list, 4146 // except that the aforementioned are allowed in unevaluated 4147 // expressions. Everything else falls under the 4148 // "may accept other forms of constant expressions" exception. 4149 // (We never end up here for C++, so the constant expression 4150 // rules there don't matter.) 4151 if (Init->isConstantInitializer(Context, false)) 4152 return false; 4153 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4154 << Init->getSourceRange(); 4155 return true; 4156} 4157 4158void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4159 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4160} 4161 4162/// AddInitializerToDecl - Adds the initializer Init to the 4163/// declaration dcl. If DirectInit is true, this is C++ direct 4164/// initialization rather than copy initialization. 4165void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4166 // If there is no declaration, there was an error parsing it. Just ignore 4167 // the initializer. 4168 if (RealDecl == 0) 4169 return; 4170 4171 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4172 // With declarators parsed the way they are, the parser cannot 4173 // distinguish between a normal initializer and a pure-specifier. 4174 // Thus this grotesque test. 4175 IntegerLiteral *IL; 4176 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4177 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4178 CheckPureMethod(Method, Init->getSourceRange()); 4179 else { 4180 Diag(Method->getLocation(), diag::err_member_function_initialization) 4181 << Method->getDeclName() << Init->getSourceRange(); 4182 Method->setInvalidDecl(); 4183 } 4184 return; 4185 } 4186 4187 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4188 if (!VDecl) { 4189 if (getLangOptions().CPlusPlus && 4190 RealDecl->getLexicalDeclContext()->isRecord() && 4191 isa<NamedDecl>(RealDecl)) 4192 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4193 else 4194 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4195 RealDecl->setInvalidDecl(); 4196 return; 4197 } 4198 4199 4200 4201 // A definition must end up with a complete type, which means it must be 4202 // complete with the restriction that an array type might be completed by the 4203 // initializer; note that later code assumes this restriction. 4204 QualType BaseDeclType = VDecl->getType(); 4205 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4206 BaseDeclType = Array->getElementType(); 4207 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4208 diag::err_typecheck_decl_incomplete_type)) { 4209 RealDecl->setInvalidDecl(); 4210 return; 4211 } 4212 4213 // The variable can not have an abstract class type. 4214 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4215 diag::err_abstract_type_in_decl, 4216 AbstractVariableType)) 4217 VDecl->setInvalidDecl(); 4218 4219 const VarDecl *Def; 4220 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4221 Diag(VDecl->getLocation(), diag::err_redefinition) 4222 << VDecl->getDeclName(); 4223 Diag(Def->getLocation(), diag::note_previous_definition); 4224 VDecl->setInvalidDecl(); 4225 return; 4226 } 4227 4228 // C++ [class.static.data]p4 4229 // If a static data member is of const integral or const 4230 // enumeration type, its declaration in the class definition can 4231 // specify a constant-initializer which shall be an integral 4232 // constant expression (5.19). In that case, the member can appear 4233 // in integral constant expressions. The member shall still be 4234 // defined in a namespace scope if it is used in the program and the 4235 // namespace scope definition shall not contain an initializer. 4236 // 4237 // We already performed a redefinition check above, but for static 4238 // data members we also need to check whether there was an in-class 4239 // declaration with an initializer. 4240 const VarDecl* PrevInit = 0; 4241 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4242 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4243 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4244 return; 4245 } 4246 4247 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4248 getCurFunction()->setHasBranchProtectedScope(); 4249 4250 // Capture the variable that is being initialized and the style of 4251 // initialization. 4252 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4253 4254 // FIXME: Poor source location information. 4255 InitializationKind Kind 4256 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4257 Init->getLocStart(), 4258 Init->getLocEnd()) 4259 : InitializationKind::CreateCopy(VDecl->getLocation(), 4260 Init->getLocStart()); 4261 4262 // Get the decls type and save a reference for later, since 4263 // CheckInitializerTypes may change it. 4264 QualType DclT = VDecl->getType(), SavT = DclT; 4265 if (VDecl->isLocalVarDecl()) { 4266 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4267 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4268 VDecl->setInvalidDecl(); 4269 } else if (!VDecl->isInvalidDecl()) { 4270 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4271 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4272 MultiExprArg(*this, &Init, 1), 4273 &DclT); 4274 if (Result.isInvalid()) { 4275 VDecl->setInvalidDecl(); 4276 return; 4277 } 4278 4279 Init = Result.takeAs<Expr>(); 4280 4281 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4282 // Don't check invalid declarations to avoid emitting useless diagnostics. 4283 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4284 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4285 CheckForConstantInitializer(Init, DclT); 4286 } 4287 } 4288 } else if (VDecl->isStaticDataMember() && 4289 VDecl->getLexicalDeclContext()->isRecord()) { 4290 // This is an in-class initialization for a static data member, e.g., 4291 // 4292 // struct S { 4293 // static const int value = 17; 4294 // }; 4295 4296 // Try to perform the initialization regardless. 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++ [class.mem]p4: 4311 // A member-declarator can contain a constant-initializer only 4312 // if it declares a static member (9.4) of const integral or 4313 // const enumeration type, see 9.4.2. 4314 QualType T = VDecl->getType(); 4315 4316 // Do nothing on dependent types. 4317 if (T->isDependentType()) { 4318 4319 // Require constness. 4320 } else if (!T.isConstQualified()) { 4321 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4322 << Init->getSourceRange(); 4323 VDecl->setInvalidDecl(); 4324 4325 // We allow integer constant expressions in all cases. 4326 } else if (T->isIntegralOrEnumerationType()) { 4327 if (!Init->isValueDependent()) { 4328 // Check whether the expression is a constant expression. 4329 llvm::APSInt Value; 4330 SourceLocation Loc; 4331 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4332 Diag(Loc, diag::err_in_class_initializer_non_constant) 4333 << Init->getSourceRange(); 4334 VDecl->setInvalidDecl(); 4335 } 4336 } 4337 4338 // We allow floating-point constants as an extension in C++03, and 4339 // C++0x has far more complicated rules that we don't really 4340 // implement fully. 4341 } else { 4342 bool Allowed = false; 4343 if (getLangOptions().CPlusPlus0x) { 4344 Allowed = T->isLiteralType(); 4345 } else if (T->isFloatingType()) { // also permits complex, which is ok 4346 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4347 << T << Init->getSourceRange(); 4348 Allowed = true; 4349 } 4350 4351 if (!Allowed) { 4352 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4353 << T << Init->getSourceRange(); 4354 VDecl->setInvalidDecl(); 4355 4356 // TODO: there are probably expressions that pass here that shouldn't. 4357 } else if (!Init->isValueDependent() && 4358 !Init->isConstantInitializer(Context, false)) { 4359 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4360 << Init->getSourceRange(); 4361 VDecl->setInvalidDecl(); 4362 } 4363 } 4364 } else if (VDecl->isFileVarDecl()) { 4365 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4366 (!getLangOptions().CPlusPlus || 4367 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4368 Diag(VDecl->getLocation(), diag::warn_extern_init); 4369 if (!VDecl->isInvalidDecl()) { 4370 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4371 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4372 MultiExprArg(*this, &Init, 1), 4373 &DclT); 4374 if (Result.isInvalid()) { 4375 VDecl->setInvalidDecl(); 4376 return; 4377 } 4378 4379 Init = Result.takeAs<Expr>(); 4380 } 4381 4382 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4383 // Don't check invalid declarations to avoid emitting useless diagnostics. 4384 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4385 // C99 6.7.8p4. All file scoped initializers need to be constant. 4386 CheckForConstantInitializer(Init, DclT); 4387 } 4388 } 4389 // If the type changed, it means we had an incomplete type that was 4390 // completed by the initializer. For example: 4391 // int ary[] = { 1, 3, 5 }; 4392 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4393 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4394 VDecl->setType(DclT); 4395 Init->setType(DclT); 4396 } 4397 4398 4399 // If this variable is a local declaration with record type, make sure it 4400 // doesn't have a flexible member initialization. We only support this as a 4401 // global/static definition. 4402 if (VDecl->hasLocalStorage()) 4403 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4404 if (RT->getDecl()->hasFlexibleArrayMember()) { 4405 // Check whether the initializer tries to initialize the flexible 4406 // array member itself to anything other than an empty initializer list. 4407 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 4408 unsigned Index = std::distance(RT->getDecl()->field_begin(), 4409 RT->getDecl()->field_end()) - 1; 4410 if (Index < ILE->getNumInits() && 4411 !(isa<InitListExpr>(ILE->getInit(Index)) && 4412 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 4413 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4414 VDecl->setInvalidDecl(); 4415 } 4416 } 4417 } 4418 4419 // Check any implicit conversions within the expression. 4420 CheckImplicitConversions(Init, VDecl->getLocation()); 4421 4422 Init = MaybeCreateCXXExprWithTemporaries(Init); 4423 // Attach the initializer to the decl. 4424 VDecl->setInit(Init); 4425 4426 if (getLangOptions().CPlusPlus) { 4427 if (!VDecl->isInvalidDecl() && 4428 !VDecl->getDeclContext()->isDependentContext() && 4429 VDecl->hasGlobalStorage() && !VDecl->isStaticLocal() && 4430 !Init->isConstantInitializer(Context, 4431 VDecl->getType()->isReferenceType())) 4432 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4433 << Init->getSourceRange(); 4434 4435 // Make sure we mark the destructor as used if necessary. 4436 QualType InitType = VDecl->getType(); 4437 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4438 InitType = Context.getBaseElementType(Array); 4439 if (const RecordType *Record = InitType->getAs<RecordType>()) 4440 FinalizeVarWithDestructor(VDecl, Record); 4441 } 4442 4443 return; 4444} 4445 4446/// ActOnInitializerError - Given that there was an error parsing an 4447/// initializer for the given declaration, try to return to some form 4448/// of sanity. 4449void Sema::ActOnInitializerError(Decl *D) { 4450 // Our main concern here is re-establishing invariants like "a 4451 // variable's type is either dependent or complete". 4452 if (!D || D->isInvalidDecl()) return; 4453 4454 VarDecl *VD = dyn_cast<VarDecl>(D); 4455 if (!VD) return; 4456 4457 QualType Ty = VD->getType(); 4458 if (Ty->isDependentType()) return; 4459 4460 // Require a complete type. 4461 if (RequireCompleteType(VD->getLocation(), 4462 Context.getBaseElementType(Ty), 4463 diag::err_typecheck_decl_incomplete_type)) { 4464 VD->setInvalidDecl(); 4465 return; 4466 } 4467 4468 // Require an abstract type. 4469 if (RequireNonAbstractType(VD->getLocation(), Ty, 4470 diag::err_abstract_type_in_decl, 4471 AbstractVariableType)) { 4472 VD->setInvalidDecl(); 4473 return; 4474 } 4475 4476 // Don't bother complaining about constructors or destructors, 4477 // though. 4478} 4479 4480void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4481 bool TypeContainsUndeducedAuto) { 4482 // If there is no declaration, there was an error parsing it. Just ignore it. 4483 if (RealDecl == 0) 4484 return; 4485 4486 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4487 QualType Type = Var->getType(); 4488 4489 // C++0x [dcl.spec.auto]p3 4490 if (TypeContainsUndeducedAuto) { 4491 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4492 << Var->getDeclName() << Type; 4493 Var->setInvalidDecl(); 4494 return; 4495 } 4496 4497 switch (Var->isThisDeclarationADefinition()) { 4498 case VarDecl::Definition: 4499 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4500 break; 4501 4502 // We have an out-of-line definition of a static data member 4503 // that has an in-class initializer, so we type-check this like 4504 // a declaration. 4505 // 4506 // Fall through 4507 4508 case VarDecl::DeclarationOnly: 4509 // It's only a declaration. 4510 4511 // Block scope. C99 6.7p7: If an identifier for an object is 4512 // declared with no linkage (C99 6.2.2p6), the type for the 4513 // object shall be complete. 4514 if (!Type->isDependentType() && Var->isLocalVarDecl() && 4515 !Var->getLinkage() && !Var->isInvalidDecl() && 4516 RequireCompleteType(Var->getLocation(), Type, 4517 diag::err_typecheck_decl_incomplete_type)) 4518 Var->setInvalidDecl(); 4519 4520 // Make sure that the type is not abstract. 4521 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4522 RequireNonAbstractType(Var->getLocation(), Type, 4523 diag::err_abstract_type_in_decl, 4524 AbstractVariableType)) 4525 Var->setInvalidDecl(); 4526 return; 4527 4528 case VarDecl::TentativeDefinition: 4529 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4530 // object that has file scope without an initializer, and without a 4531 // storage-class specifier or with the storage-class specifier "static", 4532 // constitutes a tentative definition. Note: A tentative definition with 4533 // external linkage is valid (C99 6.2.2p5). 4534 if (!Var->isInvalidDecl()) { 4535 if (const IncompleteArrayType *ArrayT 4536 = Context.getAsIncompleteArrayType(Type)) { 4537 if (RequireCompleteType(Var->getLocation(), 4538 ArrayT->getElementType(), 4539 diag::err_illegal_decl_array_incomplete_type)) 4540 Var->setInvalidDecl(); 4541 } else if (Var->getStorageClass() == SC_Static) { 4542 // C99 6.9.2p3: If the declaration of an identifier for an object is 4543 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4544 // declared type shall not be an incomplete type. 4545 // NOTE: code such as the following 4546 // static struct s; 4547 // struct s { int a; }; 4548 // is accepted by gcc. Hence here we issue a warning instead of 4549 // an error and we do not invalidate the static declaration. 4550 // NOTE: to avoid multiple warnings, only check the first declaration. 4551 if (Var->getPreviousDeclaration() == 0) 4552 RequireCompleteType(Var->getLocation(), Type, 4553 diag::ext_typecheck_decl_incomplete_type); 4554 } 4555 } 4556 4557 // Record the tentative definition; we're done. 4558 if (!Var->isInvalidDecl()) 4559 TentativeDefinitions.push_back(Var); 4560 return; 4561 } 4562 4563 // Provide a specific diagnostic for uninitialized variable 4564 // definitions with incomplete array type. 4565 if (Type->isIncompleteArrayType()) { 4566 Diag(Var->getLocation(), 4567 diag::err_typecheck_incomplete_array_needs_initializer); 4568 Var->setInvalidDecl(); 4569 return; 4570 } 4571 4572 // Provide a specific diagnostic for uninitialized variable 4573 // definitions with reference type. 4574 if (Type->isReferenceType()) { 4575 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4576 << Var->getDeclName() 4577 << SourceRange(Var->getLocation(), Var->getLocation()); 4578 Var->setInvalidDecl(); 4579 return; 4580 } 4581 4582 // Do not attempt to type-check the default initializer for a 4583 // variable with dependent type. 4584 if (Type->isDependentType()) 4585 return; 4586 4587 if (Var->isInvalidDecl()) 4588 return; 4589 4590 if (RequireCompleteType(Var->getLocation(), 4591 Context.getBaseElementType(Type), 4592 diag::err_typecheck_decl_incomplete_type)) { 4593 Var->setInvalidDecl(); 4594 return; 4595 } 4596 4597 // The variable can not have an abstract class type. 4598 if (RequireNonAbstractType(Var->getLocation(), Type, 4599 diag::err_abstract_type_in_decl, 4600 AbstractVariableType)) { 4601 Var->setInvalidDecl(); 4602 return; 4603 } 4604 4605 const RecordType *Record 4606 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4607 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4608 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4609 // C++03 [dcl.init]p9: 4610 // If no initializer is specified for an object, and the 4611 // object is of (possibly cv-qualified) non-POD class type (or 4612 // array thereof), the object shall be default-initialized; if 4613 // the object is of const-qualified type, the underlying class 4614 // type shall have a user-declared default 4615 // constructor. Otherwise, if no initializer is specified for 4616 // a non- static object, the object and its subobjects, if 4617 // any, have an indeterminate initial value); if the object 4618 // or any of its subobjects are of const-qualified type, the 4619 // program is ill-formed. 4620 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4621 } else { 4622 // Check for jumps past the implicit initializer. C++0x 4623 // clarifies that this applies to a "variable with automatic 4624 // storage duration", not a "local variable". 4625 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4626 getCurFunction()->setHasBranchProtectedScope(); 4627 4628 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4629 InitializationKind Kind 4630 = InitializationKind::CreateDefault(Var->getLocation()); 4631 4632 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4633 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4634 MultiExprArg(*this, 0, 0)); 4635 if (Init.isInvalid()) 4636 Var->setInvalidDecl(); 4637 else if (Init.get()) { 4638 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4639 4640 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4641 Var->hasGlobalStorage() && !Var->isStaticLocal() && 4642 !Var->getDeclContext()->isDependentContext() && 4643 !Var->getInit()->isConstantInitializer(Context, false)) 4644 Diag(Var->getLocation(), diag::warn_global_constructor); 4645 } 4646 } 4647 4648 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4649 FinalizeVarWithDestructor(Var, Record); 4650 } 4651} 4652 4653Sema::DeclGroupPtrTy 4654Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4655 Decl **Group, unsigned NumDecls) { 4656 llvm::SmallVector<Decl*, 8> Decls; 4657 4658 if (DS.isTypeSpecOwned()) 4659 Decls.push_back(DS.getRepAsDecl()); 4660 4661 for (unsigned i = 0; i != NumDecls; ++i) 4662 if (Decl *D = Group[i]) 4663 Decls.push_back(D); 4664 4665 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4666 Decls.data(), Decls.size())); 4667} 4668 4669 4670/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4671/// to introduce parameters into function prototype scope. 4672Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4673 const DeclSpec &DS = D.getDeclSpec(); 4674 4675 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4676 VarDecl::StorageClass StorageClass = SC_None; 4677 VarDecl::StorageClass StorageClassAsWritten = SC_None; 4678 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4679 StorageClass = SC_Register; 4680 StorageClassAsWritten = SC_Register; 4681 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4682 Diag(DS.getStorageClassSpecLoc(), 4683 diag::err_invalid_storage_class_in_func_decl); 4684 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4685 } 4686 4687 if (D.getDeclSpec().isThreadSpecified()) 4688 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4689 4690 DiagnoseFunctionSpecifiers(D); 4691 4692 // Check that there are no default arguments inside the type of this 4693 // parameter (C++ only). 4694 if (getLangOptions().CPlusPlus) 4695 CheckExtraCXXDefaultArguments(D); 4696 4697 TagDecl *OwnedDecl = 0; 4698 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4699 QualType parmDeclType = TInfo->getType(); 4700 4701 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4702 // C++ [dcl.fct]p6: 4703 // Types shall not be defined in return or parameter types. 4704 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4705 << Context.getTypeDeclType(OwnedDecl); 4706 } 4707 4708 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4709 IdentifierInfo *II = D.getIdentifier(); 4710 if (II) { 4711 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4712 ForRedeclaration); 4713 LookupName(R, S); 4714 if (R.isSingleResult()) { 4715 NamedDecl *PrevDecl = R.getFoundDecl(); 4716 if (PrevDecl->isTemplateParameter()) { 4717 // Maybe we will complain about the shadowed template parameter. 4718 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4719 // Just pretend that we didn't see the previous declaration. 4720 PrevDecl = 0; 4721 } else if (S->isDeclScope(PrevDecl)) { 4722 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4723 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4724 4725 // Recover by removing the name 4726 II = 0; 4727 D.SetIdentifier(0, D.getIdentifierLoc()); 4728 D.setInvalidType(true); 4729 } 4730 } 4731 } 4732 4733 // Temporarily put parameter variables in the translation unit, not 4734 // the enclosing context. This prevents them from accidentally 4735 // looking like class members in C++. 4736 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4737 TInfo, parmDeclType, II, 4738 D.getIdentifierLoc(), 4739 StorageClass, StorageClassAsWritten); 4740 4741 if (D.isInvalidType()) 4742 New->setInvalidDecl(); 4743 4744 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4745 if (D.getCXXScopeSpec().isSet()) { 4746 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4747 << D.getCXXScopeSpec().getRange(); 4748 New->setInvalidDecl(); 4749 } 4750 4751 // Add the parameter declaration into this scope. 4752 S->AddDecl(New); 4753 if (II) 4754 IdResolver.AddDecl(New); 4755 4756 ProcessDeclAttributes(S, New, D); 4757 4758 if (New->hasAttr<BlocksAttr>()) { 4759 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4760 } 4761 return New; 4762} 4763 4764/// \brief Synthesizes a variable for a parameter arising from a 4765/// typedef. 4766ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4767 SourceLocation Loc, 4768 QualType T) { 4769 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4770 T, Context.getTrivialTypeSourceInfo(T, Loc), 4771 SC_None, SC_None, 0); 4772 Param->setImplicit(); 4773 return Param; 4774} 4775 4776void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 4777 ParmVarDecl * const *ParamEnd) { 4778 if (Diags.getDiagnosticLevel(diag::warn_unused_parameter) == 4779 Diagnostic::Ignored) 4780 return; 4781 4782 // Don't diagnose unused-parameter errors in template instantiations; we 4783 // will already have done so in the template itself. 4784 if (!ActiveTemplateInstantiations.empty()) 4785 return; 4786 4787 for (; Param != ParamEnd; ++Param) { 4788 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 4789 !(*Param)->hasAttr<UnusedAttr>()) { 4790 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 4791 << (*Param)->getDeclName(); 4792 } 4793 } 4794} 4795 4796ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4797 TypeSourceInfo *TSInfo, QualType T, 4798 IdentifierInfo *Name, 4799 SourceLocation NameLoc, 4800 VarDecl::StorageClass StorageClass, 4801 VarDecl::StorageClass StorageClassAsWritten) { 4802 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4803 adjustParameterType(T), TSInfo, 4804 StorageClass, StorageClassAsWritten, 4805 0); 4806 4807 // Parameters can not be abstract class types. 4808 // For record types, this is done by the AbstractClassUsageDiagnoser once 4809 // the class has been completely parsed. 4810 if (!CurContext->isRecord() && 4811 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4812 AbstractParamType)) 4813 New->setInvalidDecl(); 4814 4815 // Parameter declarators cannot be interface types. All ObjC objects are 4816 // passed by reference. 4817 if (T->isObjCObjectType()) { 4818 Diag(NameLoc, 4819 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4820 New->setInvalidDecl(); 4821 } 4822 4823 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4824 // duration shall not be qualified by an address-space qualifier." 4825 // Since all parameters have automatic store duration, they can not have 4826 // an address space. 4827 if (T.getAddressSpace() != 0) { 4828 Diag(NameLoc, diag::err_arg_with_address_space); 4829 New->setInvalidDecl(); 4830 } 4831 4832 return New; 4833} 4834 4835void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4836 SourceLocation LocAfterDecls) { 4837 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4838 "Not a function declarator!"); 4839 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4840 4841 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4842 // for a K&R function. 4843 if (!FTI.hasPrototype) { 4844 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4845 --i; 4846 if (FTI.ArgInfo[i].Param == 0) { 4847 llvm::SmallString<256> Code; 4848 llvm::raw_svector_ostream(Code) << " int " 4849 << FTI.ArgInfo[i].Ident->getName() 4850 << ";\n"; 4851 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4852 << FTI.ArgInfo[i].Ident 4853 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4854 4855 // Implicitly declare the argument as type 'int' for lack of a better 4856 // type. 4857 DeclSpec DS; 4858 const char* PrevSpec; // unused 4859 unsigned DiagID; // unused 4860 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4861 PrevSpec, DiagID); 4862 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4863 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4864 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4865 } 4866 } 4867 } 4868} 4869 4870Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4871 Declarator &D) { 4872 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4873 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4874 "Not a function declarator!"); 4875 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4876 4877 if (FTI.hasPrototype) { 4878 // FIXME: Diagnose arguments without names in C. 4879 } 4880 4881 Scope *ParentScope = FnBodyScope->getParent(); 4882 4883 Decl *DP = HandleDeclarator(ParentScope, D, 4884 MultiTemplateParamsArg(*this), 4885 /*IsFunctionDefinition=*/true); 4886 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4887} 4888 4889static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4890 // Don't warn about invalid declarations. 4891 if (FD->isInvalidDecl()) 4892 return false; 4893 4894 // Or declarations that aren't global. 4895 if (!FD->isGlobal()) 4896 return false; 4897 4898 // Don't warn about C++ member functions. 4899 if (isa<CXXMethodDecl>(FD)) 4900 return false; 4901 4902 // Don't warn about 'main'. 4903 if (FD->isMain()) 4904 return false; 4905 4906 // Don't warn about inline functions. 4907 if (FD->isInlineSpecified()) 4908 return false; 4909 4910 // Don't warn about function templates. 4911 if (FD->getDescribedFunctionTemplate()) 4912 return false; 4913 4914 // Don't warn about function template specializations. 4915 if (FD->isFunctionTemplateSpecialization()) 4916 return false; 4917 4918 bool MissingPrototype = true; 4919 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4920 Prev; Prev = Prev->getPreviousDeclaration()) { 4921 // Ignore any declarations that occur in function or method 4922 // scope, because they aren't visible from the header. 4923 if (Prev->getDeclContext()->isFunctionOrMethod()) 4924 continue; 4925 4926 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4927 break; 4928 } 4929 4930 return MissingPrototype; 4931} 4932 4933Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4934 // Clear the last template instantiation error context. 4935 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4936 4937 if (!D) 4938 return D; 4939 FunctionDecl *FD = 0; 4940 4941 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4942 FD = FunTmpl->getTemplatedDecl(); 4943 else 4944 FD = cast<FunctionDecl>(D); 4945 4946 // Enter a new function scope 4947 PushFunctionScope(); 4948 4949 // See if this is a redefinition. 4950 // But don't complain if we're in GNU89 mode and the previous definition 4951 // was an extern inline function. 4952 const FunctionDecl *Definition; 4953 if (FD->hasBody(Definition) && 4954 !canRedefineFunction(Definition, getLangOptions())) { 4955 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 4956 Definition->getStorageClass() == SC_Extern) 4957 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 4958 << FD->getDeclName() << getLangOptions().CPlusPlus; 4959 else 4960 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4961 Diag(Definition->getLocation(), diag::note_previous_definition); 4962 } 4963 4964 // Builtin functions cannot be defined. 4965 if (unsigned BuiltinID = FD->getBuiltinID()) { 4966 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4967 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4968 FD->setInvalidDecl(); 4969 } 4970 } 4971 4972 // The return type of a function definition must be complete 4973 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4974 QualType ResultType = FD->getResultType(); 4975 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4976 !FD->isInvalidDecl() && 4977 RequireCompleteType(FD->getLocation(), ResultType, 4978 diag::err_func_def_incomplete_result)) 4979 FD->setInvalidDecl(); 4980 4981 // GNU warning -Wmissing-prototypes: 4982 // Warn if a global function is defined without a previous 4983 // prototype declaration. This warning is issued even if the 4984 // definition itself provides a prototype. The aim is to detect 4985 // global functions that fail to be declared in header files. 4986 if (ShouldWarnAboutMissingPrototype(FD)) 4987 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4988 4989 if (FnBodyScope) 4990 PushDeclContext(FnBodyScope, FD); 4991 4992 // Check the validity of our function parameters 4993 CheckParmsForFunctionDef(FD); 4994 4995 bool ShouldCheckShadow = 4996 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4997 4998 // Introduce our parameters into the function scope 4999 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 5000 ParmVarDecl *Param = FD->getParamDecl(p); 5001 Param->setOwningFunction(FD); 5002 5003 // If this has an identifier, add it to the scope stack. 5004 if (Param->getIdentifier() && FnBodyScope) { 5005 if (ShouldCheckShadow) 5006 CheckShadow(FnBodyScope, Param); 5007 5008 PushOnScopeChains(Param, FnBodyScope); 5009 } 5010 } 5011 5012 // Checking attributes of current function definition 5013 // dllimport attribute. 5014 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 5015 if (DA && (!FD->getAttr<DLLExportAttr>())) { 5016 // dllimport attribute cannot be directly applied to definition. 5017 if (!DA->isInherited()) { 5018 Diag(FD->getLocation(), 5019 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 5020 << "dllimport"; 5021 FD->setInvalidDecl(); 5022 return FD; 5023 } 5024 5025 // Visual C++ appears to not think this is an issue, so only issue 5026 // a warning when Microsoft extensions are disabled. 5027 if (!LangOpts.Microsoft) { 5028 // If a symbol previously declared dllimport is later defined, the 5029 // attribute is ignored in subsequent references, and a warning is 5030 // emitted. 5031 Diag(FD->getLocation(), 5032 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5033 << FD->getName() << "dllimport"; 5034 } 5035 } 5036 return FD; 5037} 5038 5039/// \brief Given the set of return statements within a function body, 5040/// compute the variables that are subject to the named return value 5041/// optimization. 5042/// 5043/// Each of the variables that is subject to the named return value 5044/// optimization will be marked as NRVO variables in the AST, and any 5045/// return statement that has a marked NRVO variable as its NRVO candidate can 5046/// use the named return value optimization. 5047/// 5048/// This function applies a very simplistic algorithm for NRVO: if every return 5049/// statement in the function has the same NRVO candidate, that candidate is 5050/// the NRVO variable. 5051/// 5052/// FIXME: Employ a smarter algorithm that accounts for multiple return 5053/// statements and the lifetimes of the NRVO candidates. We should be able to 5054/// find a maximal set of NRVO variables. 5055static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5056 ReturnStmt **Returns = Scope->Returns.data(); 5057 5058 const VarDecl *NRVOCandidate = 0; 5059 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5060 if (!Returns[I]->getNRVOCandidate()) 5061 return; 5062 5063 if (!NRVOCandidate) 5064 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5065 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5066 return; 5067 } 5068 5069 if (NRVOCandidate) 5070 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5071} 5072 5073Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5074 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5075} 5076 5077Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5078 bool IsInstantiation) { 5079 FunctionDecl *FD = 0; 5080 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5081 if (FunTmpl) 5082 FD = FunTmpl->getTemplatedDecl(); 5083 else 5084 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5085 5086 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5087 5088 if (FD) { 5089 FD->setBody(Body); 5090 if (FD->isMain()) { 5091 // C and C++ allow for main to automagically return 0. 5092 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5093 FD->setHasImplicitReturnZero(true); 5094 WP.disableCheckFallThrough(); 5095 } 5096 5097 if (!FD->isInvalidDecl()) { 5098 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5099 5100 // If this is a constructor, we need a vtable. 5101 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5102 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5103 5104 ComputeNRVO(Body, getCurFunction()); 5105 } 5106 5107 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5108 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5109 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5110 MD->setBody(Body); 5111 MD->setEndLoc(Body->getLocEnd()); 5112 if (!MD->isInvalidDecl()) 5113 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5114 } else { 5115 return 0; 5116 } 5117 5118 // Verify and clean out per-function state. 5119 5120 // Check goto/label use. 5121 FunctionScopeInfo *CurFn = getCurFunction(); 5122 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 5123 I = CurFn->LabelMap.begin(), E = CurFn->LabelMap.end(); I != E; ++I) { 5124 LabelStmt *L = I->second; 5125 5126 // Verify that we have no forward references left. If so, there was a goto 5127 // or address of a label taken, but no definition of it. Label fwd 5128 // definitions are indicated with a null substmt. 5129 if (L->getSubStmt() != 0) { 5130 if (!L->isUsed()) 5131 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 5132 continue; 5133 } 5134 5135 // Emit error. 5136 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 5137 5138 // At this point, we have gotos that use the bogus label. Stitch it into 5139 // the function body so that they aren't leaked and that the AST is well 5140 // formed. 5141 if (Body == 0) { 5142 // The whole function wasn't parsed correctly. 5143 continue; 5144 } 5145 5146 // Otherwise, the body is valid: we want to stitch the label decl into the 5147 // function somewhere so that it is properly owned and so that the goto 5148 // has a valid target. Do this by creating a new compound stmt with the 5149 // label in it. 5150 5151 // Give the label a sub-statement. 5152 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 5153 5154 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 5155 cast<CXXTryStmt>(Body)->getTryBlock() : 5156 cast<CompoundStmt>(Body); 5157 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 5158 Compound->body_end()); 5159 Elements.push_back(L); 5160 Compound->setStmts(Context, Elements.data(), Elements.size()); 5161 } 5162 5163 if (Body) { 5164 // C++ constructors that have function-try-blocks can't have return 5165 // statements in the handlers of that block. (C++ [except.handle]p14) 5166 // Verify this. 5167 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5168 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5169 5170 // Verify that that gotos and switch cases don't jump into scopes illegally. 5171 // Verify that that gotos and switch cases don't jump into scopes illegally. 5172 if (getCurFunction()->NeedsScopeChecking() && 5173 !dcl->isInvalidDecl() && 5174 !hasAnyErrorsInThisFunction()) 5175 DiagnoseInvalidJumps(Body); 5176 5177 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5178 if (!Destructor->getParent()->isDependentType()) 5179 CheckDestructor(Destructor); 5180 5181 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5182 Destructor->getParent()); 5183 } 5184 5185 // If any errors have occurred, clear out any temporaries that may have 5186 // been leftover. This ensures that these temporaries won't be picked up for 5187 // deletion in some later function. 5188 if (PP.getDiagnostics().hasErrorOccurred()) 5189 ExprTemporaries.clear(); 5190 else if (!isa<FunctionTemplateDecl>(dcl)) { 5191 // Since the body is valid, issue any analysis-based warnings that are 5192 // enabled. 5193 QualType ResultType; 5194 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 5195 AnalysisWarnings.IssueWarnings(WP, FD); 5196 } else { 5197 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 5198 AnalysisWarnings.IssueWarnings(WP, MD); 5199 } 5200 } 5201 5202 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5203 } 5204 5205 if (!IsInstantiation) 5206 PopDeclContext(); 5207 5208 PopFunctionOrBlockScope(); 5209 5210 // If any errors have occurred, clear out any temporaries that may have 5211 // been leftover. This ensures that these temporaries won't be picked up for 5212 // deletion in some later function. 5213 if (getDiagnostics().hasErrorOccurred()) 5214 ExprTemporaries.clear(); 5215 5216 return dcl; 5217} 5218 5219/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5220/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5221NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5222 IdentifierInfo &II, Scope *S) { 5223 // Before we produce a declaration for an implicitly defined 5224 // function, see whether there was a locally-scoped declaration of 5225 // this name as a function or variable. If so, use that 5226 // (non-visible) declaration, and complain about it. 5227 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5228 = LocallyScopedExternalDecls.find(&II); 5229 if (Pos != LocallyScopedExternalDecls.end()) { 5230 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5231 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5232 return Pos->second; 5233 } 5234 5235 // Extension in C99. Legal in C90, but warn about it. 5236 if (II.getName().startswith("__builtin_")) 5237 Diag(Loc, diag::warn_builtin_unknown) << &II; 5238 else if (getLangOptions().C99) 5239 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5240 else 5241 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5242 5243 // Set a Declarator for the implicit definition: int foo(); 5244 const char *Dummy; 5245 DeclSpec DS; 5246 unsigned DiagID; 5247 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5248 Error = Error; // Silence warning. 5249 assert(!Error && "Error setting up implicit decl!"); 5250 Declarator D(DS, Declarator::BlockContext); 5251 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5252 0, 0, false, SourceLocation(), 5253 false, 0,0,0, Loc, Loc, D), 5254 SourceLocation()); 5255 D.SetIdentifier(&II, Loc); 5256 5257 // Insert this function into translation-unit scope. 5258 5259 DeclContext *PrevDC = CurContext; 5260 CurContext = Context.getTranslationUnitDecl(); 5261 5262 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5263 FD->setImplicit(); 5264 5265 CurContext = PrevDC; 5266 5267 AddKnownFunctionAttributes(FD); 5268 5269 return FD; 5270} 5271 5272/// \brief Adds any function attributes that we know a priori based on 5273/// the declaration of this function. 5274/// 5275/// These attributes can apply both to implicitly-declared builtins 5276/// (like __builtin___printf_chk) or to library-declared functions 5277/// like NSLog or printf. 5278void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5279 if (FD->isInvalidDecl()) 5280 return; 5281 5282 // If this is a built-in function, map its builtin attributes to 5283 // actual attributes. 5284 if (unsigned BuiltinID = FD->getBuiltinID()) { 5285 // Handle printf-formatting attributes. 5286 unsigned FormatIdx; 5287 bool HasVAListArg; 5288 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5289 if (!FD->getAttr<FormatAttr>()) 5290 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5291 "printf", FormatIdx+1, 5292 HasVAListArg ? 0 : FormatIdx+2)); 5293 } 5294 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5295 HasVAListArg)) { 5296 if (!FD->getAttr<FormatAttr>()) 5297 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5298 "scanf", FormatIdx+1, 5299 HasVAListArg ? 0 : FormatIdx+2)); 5300 } 5301 5302 // Mark const if we don't care about errno and that is the only 5303 // thing preventing the function from being const. This allows 5304 // IRgen to use LLVM intrinsics for such functions. 5305 if (!getLangOptions().MathErrno && 5306 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5307 if (!FD->getAttr<ConstAttr>()) 5308 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5309 } 5310 5311 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5312 FD->setType(Context.getNoReturnType(FD->getType())); 5313 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5314 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5315 if (Context.BuiltinInfo.isConst(BuiltinID)) 5316 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5317 } 5318 5319 IdentifierInfo *Name = FD->getIdentifier(); 5320 if (!Name) 5321 return; 5322 if ((!getLangOptions().CPlusPlus && 5323 FD->getDeclContext()->isTranslationUnit()) || 5324 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5325 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5326 LinkageSpecDecl::lang_c)) { 5327 // Okay: this could be a libc/libm/Objective-C function we know 5328 // about. 5329 } else 5330 return; 5331 5332 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5333 // FIXME: NSLog and NSLogv should be target specific 5334 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5335 // FIXME: We known better than our headers. 5336 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5337 } else 5338 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5339 "printf", 1, 5340 Name->isStr("NSLogv") ? 0 : 2)); 5341 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5342 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5343 // target-specific builtins, perhaps? 5344 if (!FD->getAttr<FormatAttr>()) 5345 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5346 "printf", 2, 5347 Name->isStr("vasprintf") ? 0 : 3)); 5348 } 5349} 5350 5351TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5352 TypeSourceInfo *TInfo) { 5353 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5354 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5355 5356 if (!TInfo) { 5357 assert(D.isInvalidType() && "no declarator info for valid type"); 5358 TInfo = Context.getTrivialTypeSourceInfo(T); 5359 } 5360 5361 // Scope manipulation handled by caller. 5362 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5363 D.getIdentifierLoc(), 5364 D.getIdentifier(), 5365 TInfo); 5366 5367 if (const TagType *TT = T->getAs<TagType>()) { 5368 TagDecl *TD = TT->getDecl(); 5369 5370 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5371 // keep track of the TypedefDecl. 5372 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5373 TD->setTypedefForAnonDecl(NewTD); 5374 } 5375 5376 if (D.isInvalidType()) 5377 NewTD->setInvalidDecl(); 5378 return NewTD; 5379} 5380 5381 5382/// \brief Determine whether a tag with a given kind is acceptable 5383/// as a redeclaration of the given tag declaration. 5384/// 5385/// \returns true if the new tag kind is acceptable, false otherwise. 5386bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5387 TagTypeKind NewTag, 5388 SourceLocation NewTagLoc, 5389 const IdentifierInfo &Name) { 5390 // C++ [dcl.type.elab]p3: 5391 // The class-key or enum keyword present in the 5392 // elaborated-type-specifier shall agree in kind with the 5393 // declaration to which the name in the elaborated-type-specifier 5394 // refers. This rule also applies to the form of 5395 // elaborated-type-specifier that declares a class-name or 5396 // friend class since it can be construed as referring to the 5397 // definition of the class. Thus, in any 5398 // elaborated-type-specifier, the enum keyword shall be used to 5399 // refer to an enumeration (7.2), the union class-key shall be 5400 // used to refer to a union (clause 9), and either the class or 5401 // struct class-key shall be used to refer to a class (clause 9) 5402 // declared using the class or struct class-key. 5403 TagTypeKind OldTag = Previous->getTagKind(); 5404 if (OldTag == NewTag) 5405 return true; 5406 5407 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5408 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5409 // Warn about the struct/class tag mismatch. 5410 bool isTemplate = false; 5411 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5412 isTemplate = Record->getDescribedClassTemplate(); 5413 5414 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5415 << (NewTag == TTK_Class) 5416 << isTemplate << &Name 5417 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5418 OldTag == TTK_Class? "class" : "struct"); 5419 Diag(Previous->getLocation(), diag::note_previous_use); 5420 return true; 5421 } 5422 return false; 5423} 5424 5425/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5426/// former case, Name will be non-null. In the later case, Name will be null. 5427/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5428/// reference/declaration/definition of a tag. 5429Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5430 SourceLocation KWLoc, CXXScopeSpec &SS, 5431 IdentifierInfo *Name, SourceLocation NameLoc, 5432 AttributeList *Attr, AccessSpecifier AS, 5433 MultiTemplateParamsArg TemplateParameterLists, 5434 bool &OwnedDecl, bool &IsDependent, bool ScopedEnum, 5435 TypeResult UnderlyingType) { 5436 // If this is not a definition, it must have a name. 5437 assert((Name != 0 || TUK == TUK_Definition) && 5438 "Nameless record must be a definition!"); 5439 5440 OwnedDecl = false; 5441 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5442 5443 // FIXME: Check explicit specializations more carefully. 5444 bool isExplicitSpecialization = false; 5445 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5446 bool Invalid = false; 5447 if (TUK != TUK_Reference) { 5448 if (TemplateParameterList *TemplateParams 5449 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5450 TemplateParameterLists.get(), 5451 TemplateParameterLists.size(), 5452 TUK == TUK_Friend, 5453 isExplicitSpecialization, 5454 Invalid)) { 5455 // All but one template parameter lists have been matching. 5456 --NumMatchedTemplateParamLists; 5457 5458 if (TemplateParams->size() > 0) { 5459 // This is a declaration or definition of a class template (which may 5460 // be a member of another template). 5461 if (Invalid) 5462 return 0; 5463 5464 OwnedDecl = false; 5465 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5466 SS, Name, NameLoc, Attr, 5467 TemplateParams, 5468 AS); 5469 TemplateParameterLists.release(); 5470 return Result.get(); 5471 } else { 5472 // The "template<>" header is extraneous. 5473 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5474 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5475 isExplicitSpecialization = true; 5476 } 5477 } 5478 } 5479 5480 // Figure out the underlying type if this a enum declaration. We need to do 5481 // this early, because it's needed to detect if this is an incompatible 5482 // redeclaration. 5483 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 5484 5485 if (Kind == TTK_Enum) { 5486 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 5487 // No underlying type explicitly specified, or we failed to parse the 5488 // type, default to int. 5489 EnumUnderlying = Context.IntTy.getTypePtr(); 5490 else if (UnderlyingType.get()) { 5491 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 5492 // integral type; any cv-qualification is ignored. 5493 TypeSourceInfo *TI = 0; 5494 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 5495 EnumUnderlying = TI; 5496 5497 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 5498 5499 if (!T->isDependentType() && !T->isIntegralType(Context)) { 5500 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 5501 << T; 5502 // Recover by falling back to int. 5503 EnumUnderlying = Context.IntTy.getTypePtr(); 5504 } 5505 } 5506 } 5507 5508 DeclContext *SearchDC = CurContext; 5509 DeclContext *DC = CurContext; 5510 bool isStdBadAlloc = false; 5511 5512 RedeclarationKind Redecl = ForRedeclaration; 5513 if (TUK == TUK_Friend || TUK == TUK_Reference) 5514 Redecl = NotForRedeclaration; 5515 5516 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5517 5518 if (Name && SS.isNotEmpty()) { 5519 // We have a nested-name tag ('struct foo::bar'). 5520 5521 // Check for invalid 'foo::'. 5522 if (SS.isInvalid()) { 5523 Name = 0; 5524 goto CreateNewDecl; 5525 } 5526 5527 // If this is a friend or a reference to a class in a dependent 5528 // context, don't try to make a decl for it. 5529 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5530 DC = computeDeclContext(SS, false); 5531 if (!DC) { 5532 IsDependent = true; 5533 return 0; 5534 } 5535 } else { 5536 DC = computeDeclContext(SS, true); 5537 if (!DC) { 5538 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5539 << SS.getRange(); 5540 return 0; 5541 } 5542 } 5543 5544 if (RequireCompleteDeclContext(SS, DC)) 5545 return 0; 5546 5547 SearchDC = DC; 5548 // Look-up name inside 'foo::'. 5549 LookupQualifiedName(Previous, DC); 5550 5551 if (Previous.isAmbiguous()) 5552 return 0; 5553 5554 if (Previous.empty()) { 5555 // Name lookup did not find anything. However, if the 5556 // nested-name-specifier refers to the current instantiation, 5557 // and that current instantiation has any dependent base 5558 // classes, we might find something at instantiation time: treat 5559 // this as a dependent elaborated-type-specifier. 5560 if (Previous.wasNotFoundInCurrentInstantiation()) { 5561 IsDependent = true; 5562 return 0; 5563 } 5564 5565 // A tag 'foo::bar' must already exist. 5566 Diag(NameLoc, diag::err_not_tag_in_scope) 5567 << Kind << Name << DC << SS.getRange(); 5568 Name = 0; 5569 Invalid = true; 5570 goto CreateNewDecl; 5571 } 5572 } else if (Name) { 5573 // If this is a named struct, check to see if there was a previous forward 5574 // declaration or definition. 5575 // FIXME: We're looking into outer scopes here, even when we 5576 // shouldn't be. Doing so can result in ambiguities that we 5577 // shouldn't be diagnosing. 5578 LookupName(Previous, S); 5579 5580 // Note: there used to be some attempt at recovery here. 5581 if (Previous.isAmbiguous()) 5582 return 0; 5583 5584 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5585 // FIXME: This makes sure that we ignore the contexts associated 5586 // with C structs, unions, and enums when looking for a matching 5587 // tag declaration or definition. See the similar lookup tweak 5588 // in Sema::LookupName; is there a better way to deal with this? 5589 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5590 SearchDC = SearchDC->getParent(); 5591 } 5592 } else if (S->isFunctionPrototypeScope()) { 5593 // If this is an enum declaration in function prototype scope, set its 5594 // initial context to the translation unit. 5595 SearchDC = Context.getTranslationUnitDecl(); 5596 } 5597 5598 if (Previous.isSingleResult() && 5599 Previous.getFoundDecl()->isTemplateParameter()) { 5600 // Maybe we will complain about the shadowed template parameter. 5601 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5602 // Just pretend that we didn't see the previous declaration. 5603 Previous.clear(); 5604 } 5605 5606 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5607 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5608 // This is a declaration of or a reference to "std::bad_alloc". 5609 isStdBadAlloc = true; 5610 5611 if (Previous.empty() && StdBadAlloc) { 5612 // std::bad_alloc has been implicitly declared (but made invisible to 5613 // name lookup). Fill in this implicit declaration as the previous 5614 // declaration, so that the declarations get chained appropriately. 5615 Previous.addDecl(getStdBadAlloc()); 5616 } 5617 } 5618 5619 // If we didn't find a previous declaration, and this is a reference 5620 // (or friend reference), move to the correct scope. In C++, we 5621 // also need to do a redeclaration lookup there, just in case 5622 // there's a shadow friend decl. 5623 if (Name && Previous.empty() && 5624 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5625 if (Invalid) goto CreateNewDecl; 5626 assert(SS.isEmpty()); 5627 5628 if (TUK == TUK_Reference) { 5629 // C++ [basic.scope.pdecl]p5: 5630 // -- for an elaborated-type-specifier of the form 5631 // 5632 // class-key identifier 5633 // 5634 // if the elaborated-type-specifier is used in the 5635 // decl-specifier-seq or parameter-declaration-clause of a 5636 // function defined in namespace scope, the identifier is 5637 // declared as a class-name in the namespace that contains 5638 // the declaration; otherwise, except as a friend 5639 // declaration, the identifier is declared in the smallest 5640 // non-class, non-function-prototype scope that contains the 5641 // declaration. 5642 // 5643 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5644 // C structs and unions. 5645 // 5646 // It is an error in C++ to declare (rather than define) an enum 5647 // type, including via an elaborated type specifier. We'll 5648 // diagnose that later; for now, declare the enum in the same 5649 // scope as we would have picked for any other tag type. 5650 // 5651 // GNU C also supports this behavior as part of its incomplete 5652 // enum types extension, while GNU C++ does not. 5653 // 5654 // Find the context where we'll be declaring the tag. 5655 // FIXME: We would like to maintain the current DeclContext as the 5656 // lexical context, 5657 while (SearchDC->isRecord()) 5658 SearchDC = SearchDC->getParent(); 5659 5660 // Find the scope where we'll be declaring the tag. 5661 while (S->isClassScope() || 5662 (getLangOptions().CPlusPlus && 5663 S->isFunctionPrototypeScope()) || 5664 ((S->getFlags() & Scope::DeclScope) == 0) || 5665 (S->getEntity() && 5666 ((DeclContext *)S->getEntity())->isTransparentContext())) 5667 S = S->getParent(); 5668 } else { 5669 assert(TUK == TUK_Friend); 5670 // C++ [namespace.memdef]p3: 5671 // If a friend declaration in a non-local class first declares a 5672 // class or function, the friend class or function is a member of 5673 // the innermost enclosing namespace. 5674 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5675 } 5676 5677 // In C++, we need to do a redeclaration lookup to properly 5678 // diagnose some problems. 5679 if (getLangOptions().CPlusPlus) { 5680 Previous.setRedeclarationKind(ForRedeclaration); 5681 LookupQualifiedName(Previous, SearchDC); 5682 } 5683 } 5684 5685 if (!Previous.empty()) { 5686 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5687 5688 // It's okay to have a tag decl in the same scope as a typedef 5689 // which hides a tag decl in the same scope. Finding this 5690 // insanity with a redeclaration lookup can only actually happen 5691 // in C++. 5692 // 5693 // This is also okay for elaborated-type-specifiers, which is 5694 // technically forbidden by the current standard but which is 5695 // okay according to the likely resolution of an open issue; 5696 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5697 if (getLangOptions().CPlusPlus) { 5698 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5699 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5700 TagDecl *Tag = TT->getDecl(); 5701 if (Tag->getDeclName() == Name && 5702 Tag->getDeclContext()->getRedeclContext() 5703 ->Equals(TD->getDeclContext()->getRedeclContext())) { 5704 PrevDecl = Tag; 5705 Previous.clear(); 5706 Previous.addDecl(Tag); 5707 Previous.resolveKind(); 5708 } 5709 } 5710 } 5711 } 5712 5713 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5714 // If this is a use of a previous tag, or if the tag is already declared 5715 // in the same scope (so that the definition/declaration completes or 5716 // rementions the tag), reuse the decl. 5717 if (TUK == TUK_Reference || TUK == TUK_Friend || 5718 isDeclInScope(PrevDecl, SearchDC, S)) { 5719 // Make sure that this wasn't declared as an enum and now used as a 5720 // struct or something similar. 5721 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5722 bool SafeToContinue 5723 = (PrevTagDecl->getTagKind() != TTK_Enum && 5724 Kind != TTK_Enum); 5725 if (SafeToContinue) 5726 Diag(KWLoc, diag::err_use_with_wrong_tag) 5727 << Name 5728 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5729 PrevTagDecl->getKindName()); 5730 else 5731 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5732 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5733 5734 if (SafeToContinue) 5735 Kind = PrevTagDecl->getTagKind(); 5736 else { 5737 // Recover by making this an anonymous redefinition. 5738 Name = 0; 5739 Previous.clear(); 5740 Invalid = true; 5741 } 5742 } 5743 5744 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 5745 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 5746 5747 // All conflicts with previous declarations are recovered by 5748 // returning the previous declaration. 5749 if (ScopedEnum != PrevEnum->isScoped()) { 5750 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 5751 << PrevEnum->isScoped(); 5752 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5753 return PrevTagDecl; 5754 } 5755 else if (EnumUnderlying && PrevEnum->isFixed()) { 5756 QualType T; 5757 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5758 T = TI->getType(); 5759 else 5760 T = QualType(EnumUnderlying.get<const Type*>(), 0); 5761 5762 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 5763 Diag(KWLoc, diag::err_enum_redeclare_type_mismatch); 5764 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5765 return PrevTagDecl; 5766 } 5767 } 5768 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 5769 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 5770 << PrevEnum->isFixed(); 5771 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5772 return PrevTagDecl; 5773 } 5774 } 5775 5776 if (!Invalid) { 5777 // If this is a use, just return the declaration we found. 5778 5779 // FIXME: In the future, return a variant or some other clue 5780 // for the consumer of this Decl to know it doesn't own it. 5781 // For our current ASTs this shouldn't be a problem, but will 5782 // need to be changed with DeclGroups. 5783 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5784 TUK == TUK_Friend) 5785 return PrevTagDecl; 5786 5787 // Diagnose attempts to redefine a tag. 5788 if (TUK == TUK_Definition) { 5789 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5790 // If we're defining a specialization and the previous definition 5791 // is from an implicit instantiation, don't emit an error 5792 // here; we'll catch this in the general case below. 5793 if (!isExplicitSpecialization || 5794 !isa<CXXRecordDecl>(Def) || 5795 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5796 == TSK_ExplicitSpecialization) { 5797 Diag(NameLoc, diag::err_redefinition) << Name; 5798 Diag(Def->getLocation(), diag::note_previous_definition); 5799 // If this is a redefinition, recover by making this 5800 // struct be anonymous, which will make any later 5801 // references get the previous definition. 5802 Name = 0; 5803 Previous.clear(); 5804 Invalid = true; 5805 } 5806 } else { 5807 // If the type is currently being defined, complain 5808 // about a nested redefinition. 5809 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5810 if (Tag->isBeingDefined()) { 5811 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5812 Diag(PrevTagDecl->getLocation(), 5813 diag::note_previous_definition); 5814 Name = 0; 5815 Previous.clear(); 5816 Invalid = true; 5817 } 5818 } 5819 5820 // Okay, this is definition of a previously declared or referenced 5821 // tag PrevDecl. We're going to create a new Decl for it. 5822 } 5823 } 5824 // If we get here we have (another) forward declaration or we 5825 // have a definition. Just create a new decl. 5826 5827 } else { 5828 // If we get here, this is a definition of a new tag type in a nested 5829 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5830 // new decl/type. We set PrevDecl to NULL so that the entities 5831 // have distinct types. 5832 Previous.clear(); 5833 } 5834 // If we get here, we're going to create a new Decl. If PrevDecl 5835 // is non-NULL, it's a definition of the tag declared by 5836 // PrevDecl. If it's NULL, we have a new definition. 5837 5838 5839 // Otherwise, PrevDecl is not a tag, but was found with tag 5840 // lookup. This is only actually possible in C++, where a few 5841 // things like templates still live in the tag namespace. 5842 } else { 5843 assert(getLangOptions().CPlusPlus); 5844 5845 // Use a better diagnostic if an elaborated-type-specifier 5846 // found the wrong kind of type on the first 5847 // (non-redeclaration) lookup. 5848 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5849 !Previous.isForRedeclaration()) { 5850 unsigned Kind = 0; 5851 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5852 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5853 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5854 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5855 Invalid = true; 5856 5857 // Otherwise, only diagnose if the declaration is in scope. 5858 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5859 // do nothing 5860 5861 // Diagnose implicit declarations introduced by elaborated types. 5862 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5863 unsigned Kind = 0; 5864 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5865 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5866 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5867 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5868 Invalid = true; 5869 5870 // Otherwise it's a declaration. Call out a particularly common 5871 // case here. 5872 } else if (isa<TypedefDecl>(PrevDecl)) { 5873 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5874 << Name 5875 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5876 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5877 Invalid = true; 5878 5879 // Otherwise, diagnose. 5880 } else { 5881 // The tag name clashes with something else in the target scope, 5882 // issue an error and recover by making this tag be anonymous. 5883 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5884 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5885 Name = 0; 5886 Invalid = true; 5887 } 5888 5889 // The existing declaration isn't relevant to us; we're in a 5890 // new scope, so clear out the previous declaration. 5891 Previous.clear(); 5892 } 5893 } 5894 5895CreateNewDecl: 5896 5897 TagDecl *PrevDecl = 0; 5898 if (Previous.isSingleResult()) 5899 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5900 5901 // If there is an identifier, use the location of the identifier as the 5902 // location of the decl, otherwise use the location of the struct/union 5903 // keyword. 5904 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5905 5906 // Otherwise, create a new declaration. If there is a previous 5907 // declaration of the same entity, the two will be linked via 5908 // PrevDecl. 5909 TagDecl *New; 5910 5911 bool IsForwardReference = false; 5912 if (Kind == TTK_Enum) { 5913 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5914 // enum X { A, B, C } D; D should chain to X. 5915 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5916 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 5917 !EnumUnderlying.isNull()); 5918 // If this is an undefined enum, warn. 5919 if (TUK != TUK_Definition && !Invalid) { 5920 TagDecl *Def; 5921 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 5922 // C++0x: 7.2p2: opaque-enum-declaration. 5923 // Conflicts are diagnosed above. Do nothing. 5924 } 5925 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5926 Diag(Loc, diag::ext_forward_ref_enum_def) 5927 << New; 5928 Diag(Def->getLocation(), diag::note_previous_definition); 5929 } else { 5930 unsigned DiagID = diag::ext_forward_ref_enum; 5931 if (getLangOptions().Microsoft) 5932 DiagID = diag::ext_ms_forward_ref_enum; 5933 else if (getLangOptions().CPlusPlus) 5934 DiagID = diag::err_forward_ref_enum; 5935 Diag(Loc, DiagID); 5936 5937 // If this is a forward-declared reference to an enumeration, make a 5938 // note of it; we won't actually be introducing the declaration into 5939 // the declaration context. 5940 if (TUK == TUK_Reference) 5941 IsForwardReference = true; 5942 } 5943 } 5944 5945 if (EnumUnderlying) { 5946 EnumDecl *ED = cast<EnumDecl>(New); 5947 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5948 ED->setIntegerTypeSourceInfo(TI); 5949 else 5950 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 5951 ED->setPromotionType(ED->getIntegerType()); 5952 } 5953 5954 } else { 5955 // struct/union/class 5956 5957 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5958 // struct X { int A; } D; D should chain to X. 5959 if (getLangOptions().CPlusPlus) { 5960 // FIXME: Look for a way to use RecordDecl for simple structs. 5961 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5962 cast_or_null<CXXRecordDecl>(PrevDecl)); 5963 5964 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5965 StdBadAlloc = cast<CXXRecordDecl>(New); 5966 } else 5967 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5968 cast_or_null<RecordDecl>(PrevDecl)); 5969 } 5970 5971 // Maybe add qualifier info. 5972 if (SS.isNotEmpty()) { 5973 if (SS.isSet()) { 5974 NestedNameSpecifier *NNS 5975 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5976 New->setQualifierInfo(NNS, SS.getRange()); 5977 if (NumMatchedTemplateParamLists > 0) { 5978 New->setTemplateParameterListsInfo(Context, 5979 NumMatchedTemplateParamLists, 5980 (TemplateParameterList**) TemplateParameterLists.release()); 5981 } 5982 } 5983 else 5984 Invalid = true; 5985 } 5986 5987 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5988 // Add alignment attributes if necessary; these attributes are checked when 5989 // the ASTContext lays out the structure. 5990 // 5991 // It is important for implementing the correct semantics that this 5992 // happen here (in act on tag decl). The #pragma pack stack is 5993 // maintained as a result of parser callbacks which can occur at 5994 // many points during the parsing of a struct declaration (because 5995 // the #pragma tokens are effectively skipped over during the 5996 // parsing of the struct). 5997 AddAlignmentAttributesForRecord(RD); 5998 } 5999 6000 // If this is a specialization of a member class (of a class template), 6001 // check the specialization. 6002 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 6003 Invalid = true; 6004 6005 if (Invalid) 6006 New->setInvalidDecl(); 6007 6008 if (Attr) 6009 ProcessDeclAttributeList(S, New, Attr); 6010 6011 // If we're declaring or defining a tag in function prototype scope 6012 // in C, note that this type can only be used within the function. 6013 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 6014 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 6015 6016 // Set the lexical context. If the tag has a C++ scope specifier, the 6017 // lexical context will be different from the semantic context. 6018 New->setLexicalDeclContext(CurContext); 6019 6020 // Mark this as a friend decl if applicable. 6021 if (TUK == TUK_Friend) 6022 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 6023 6024 // Set the access specifier. 6025 if (!Invalid && SearchDC->isRecord()) 6026 SetMemberAccessSpecifier(New, PrevDecl, AS); 6027 6028 if (TUK == TUK_Definition) 6029 New->startDefinition(); 6030 6031 // If this has an identifier, add it to the scope stack. 6032 if (TUK == TUK_Friend) { 6033 // We might be replacing an existing declaration in the lookup tables; 6034 // if so, borrow its access specifier. 6035 if (PrevDecl) 6036 New->setAccess(PrevDecl->getAccess()); 6037 6038 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6039 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6040 if (Name) // can be null along some error paths 6041 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6042 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6043 } else if (Name) { 6044 S = getNonFieldDeclScope(S); 6045 PushOnScopeChains(New, S, !IsForwardReference); 6046 if (IsForwardReference) 6047 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6048 6049 } else { 6050 CurContext->addDecl(New); 6051 } 6052 6053 // If this is the C FILE type, notify the AST context. 6054 if (IdentifierInfo *II = New->getIdentifier()) 6055 if (!New->isInvalidDecl() && 6056 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6057 II->isStr("FILE")) 6058 Context.setFILEDecl(New); 6059 6060 OwnedDecl = true; 6061 return New; 6062} 6063 6064void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6065 AdjustDeclIfTemplate(TagD); 6066 TagDecl *Tag = cast<TagDecl>(TagD); 6067 6068 // Enter the tag context. 6069 PushDeclContext(S, Tag); 6070} 6071 6072void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6073 SourceLocation LBraceLoc) { 6074 AdjustDeclIfTemplate(TagD); 6075 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6076 6077 FieldCollector->StartClass(); 6078 6079 if (!Record->getIdentifier()) 6080 return; 6081 6082 // C++ [class]p2: 6083 // [...] The class-name is also inserted into the scope of the 6084 // class itself; this is known as the injected-class-name. For 6085 // purposes of access checking, the injected-class-name is treated 6086 // as if it were a public member name. 6087 CXXRecordDecl *InjectedClassName 6088 = CXXRecordDecl::Create(Context, Record->getTagKind(), 6089 CurContext, Record->getLocation(), 6090 Record->getIdentifier(), 6091 Record->getTagKeywordLoc(), 6092 /*PrevDecl=*/0, 6093 /*DelayTypeCreation=*/true); 6094 Context.getTypeDeclType(InjectedClassName, Record); 6095 InjectedClassName->setImplicit(); 6096 InjectedClassName->setAccess(AS_public); 6097 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6098 InjectedClassName->setDescribedClassTemplate(Template); 6099 PushOnScopeChains(InjectedClassName, S); 6100 assert(InjectedClassName->isInjectedClassName() && 6101 "Broken injected-class-name"); 6102} 6103 6104void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6105 SourceLocation RBraceLoc) { 6106 AdjustDeclIfTemplate(TagD); 6107 TagDecl *Tag = cast<TagDecl>(TagD); 6108 Tag->setRBraceLoc(RBraceLoc); 6109 6110 if (isa<CXXRecordDecl>(Tag)) 6111 FieldCollector->FinishClass(); 6112 6113 // Exit this scope of this tag's definition. 6114 PopDeclContext(); 6115 6116 // Notify the consumer that we've defined a tag. 6117 Consumer.HandleTagDeclDefinition(Tag); 6118} 6119 6120void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6121 AdjustDeclIfTemplate(TagD); 6122 TagDecl *Tag = cast<TagDecl>(TagD); 6123 Tag->setInvalidDecl(); 6124 6125 // We're undoing ActOnTagStartDefinition here, not 6126 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6127 // the FieldCollector. 6128 6129 PopDeclContext(); 6130} 6131 6132// Note that FieldName may be null for anonymous bitfields. 6133bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6134 QualType FieldTy, const Expr *BitWidth, 6135 bool *ZeroWidth) { 6136 // Default to true; that shouldn't confuse checks for emptiness 6137 if (ZeroWidth) 6138 *ZeroWidth = true; 6139 6140 // C99 6.7.2.1p4 - verify the field type. 6141 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6142 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6143 // Handle incomplete types with specific error. 6144 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6145 return true; 6146 if (FieldName) 6147 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6148 << FieldName << FieldTy << BitWidth->getSourceRange(); 6149 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6150 << FieldTy << BitWidth->getSourceRange(); 6151 } 6152 6153 // If the bit-width is type- or value-dependent, don't try to check 6154 // it now. 6155 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6156 return false; 6157 6158 llvm::APSInt Value; 6159 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6160 return true; 6161 6162 if (Value != 0 && ZeroWidth) 6163 *ZeroWidth = false; 6164 6165 // Zero-width bitfield is ok for anonymous field. 6166 if (Value == 0 && FieldName) 6167 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6168 6169 if (Value.isSigned() && Value.isNegative()) { 6170 if (FieldName) 6171 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6172 << FieldName << Value.toString(10); 6173 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6174 << Value.toString(10); 6175 } 6176 6177 if (!FieldTy->isDependentType()) { 6178 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6179 if (Value.getZExtValue() > TypeSize) { 6180 if (!getLangOptions().CPlusPlus) { 6181 if (FieldName) 6182 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6183 << FieldName << (unsigned)Value.getZExtValue() 6184 << (unsigned)TypeSize; 6185 6186 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6187 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6188 } 6189 6190 if (FieldName) 6191 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6192 << FieldName << (unsigned)Value.getZExtValue() 6193 << (unsigned)TypeSize; 6194 else 6195 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6196 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6197 } 6198 } 6199 6200 return false; 6201} 6202 6203/// ActOnField - Each field of a struct/union/class is passed into this in order 6204/// to create a FieldDecl object for it. 6205Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6206 SourceLocation DeclStart, 6207 Declarator &D, ExprTy *BitfieldWidth) { 6208 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6209 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6210 AS_public); 6211 return Res; 6212} 6213 6214/// HandleField - Analyze a field of a C struct or a C++ data member. 6215/// 6216FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6217 SourceLocation DeclStart, 6218 Declarator &D, Expr *BitWidth, 6219 AccessSpecifier AS) { 6220 IdentifierInfo *II = D.getIdentifier(); 6221 SourceLocation Loc = DeclStart; 6222 if (II) Loc = D.getIdentifierLoc(); 6223 6224 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6225 QualType T = TInfo->getType(); 6226 if (getLangOptions().CPlusPlus) 6227 CheckExtraCXXDefaultArguments(D); 6228 6229 DiagnoseFunctionSpecifiers(D); 6230 6231 if (D.getDeclSpec().isThreadSpecified()) 6232 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6233 6234 // Check to see if this name was declared as a member previously 6235 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6236 LookupName(Previous, S); 6237 assert((Previous.empty() || Previous.isOverloadedResult() || 6238 Previous.isSingleResult()) 6239 && "Lookup of member name should be either overloaded, single or null"); 6240 6241 // If the name is overloaded then get any declaration else get the single result 6242 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6243 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6244 6245 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6246 // Maybe we will complain about the shadowed template parameter. 6247 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6248 // Just pretend that we didn't see the previous declaration. 6249 PrevDecl = 0; 6250 } 6251 6252 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6253 PrevDecl = 0; 6254 6255 bool Mutable 6256 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6257 SourceLocation TSSL = D.getSourceRange().getBegin(); 6258 FieldDecl *NewFD 6259 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6260 AS, PrevDecl, &D); 6261 6262 if (NewFD->isInvalidDecl()) 6263 Record->setInvalidDecl(); 6264 6265 if (NewFD->isInvalidDecl() && PrevDecl) { 6266 // Don't introduce NewFD into scope; there's already something 6267 // with the same name in the same scope. 6268 } else if (II) { 6269 PushOnScopeChains(NewFD, S); 6270 } else 6271 Record->addDecl(NewFD); 6272 6273 return NewFD; 6274} 6275 6276/// \brief Build a new FieldDecl and check its well-formedness. 6277/// 6278/// This routine builds a new FieldDecl given the fields name, type, 6279/// record, etc. \p PrevDecl should refer to any previous declaration 6280/// with the same name and in the same scope as the field to be 6281/// created. 6282/// 6283/// \returns a new FieldDecl. 6284/// 6285/// \todo The Declarator argument is a hack. It will be removed once 6286FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6287 TypeSourceInfo *TInfo, 6288 RecordDecl *Record, SourceLocation Loc, 6289 bool Mutable, Expr *BitWidth, 6290 SourceLocation TSSL, 6291 AccessSpecifier AS, NamedDecl *PrevDecl, 6292 Declarator *D) { 6293 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6294 bool InvalidDecl = false; 6295 if (D) InvalidDecl = D->isInvalidType(); 6296 6297 // If we receive a broken type, recover by assuming 'int' and 6298 // marking this declaration as invalid. 6299 if (T.isNull()) { 6300 InvalidDecl = true; 6301 T = Context.IntTy; 6302 } 6303 6304 QualType EltTy = Context.getBaseElementType(T); 6305 if (!EltTy->isDependentType() && 6306 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6307 // Fields of incomplete type force their record to be invalid. 6308 Record->setInvalidDecl(); 6309 InvalidDecl = true; 6310 } 6311 6312 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6313 // than a variably modified type. 6314 if (!InvalidDecl && T->isVariablyModifiedType()) { 6315 bool SizeIsNegative; 6316 llvm::APSInt Oversized; 6317 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6318 SizeIsNegative, 6319 Oversized); 6320 if (!FixedTy.isNull()) { 6321 Diag(Loc, diag::warn_illegal_constant_array_size); 6322 T = FixedTy; 6323 } else { 6324 if (SizeIsNegative) 6325 Diag(Loc, diag::err_typecheck_negative_array_size); 6326 else if (Oversized.getBoolValue()) 6327 Diag(Loc, diag::err_array_too_large) 6328 << Oversized.toString(10); 6329 else 6330 Diag(Loc, diag::err_typecheck_field_variable_size); 6331 InvalidDecl = true; 6332 } 6333 } 6334 6335 // Fields can not have abstract class types 6336 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6337 diag::err_abstract_type_in_decl, 6338 AbstractFieldType)) 6339 InvalidDecl = true; 6340 6341 bool ZeroWidth = false; 6342 // If this is declared as a bit-field, check the bit-field. 6343 if (!InvalidDecl && BitWidth && 6344 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6345 InvalidDecl = true; 6346 BitWidth = 0; 6347 ZeroWidth = false; 6348 } 6349 6350 // Check that 'mutable' is consistent with the type of the declaration. 6351 if (!InvalidDecl && Mutable) { 6352 unsigned DiagID = 0; 6353 if (T->isReferenceType()) 6354 DiagID = diag::err_mutable_reference; 6355 else if (T.isConstQualified()) 6356 DiagID = diag::err_mutable_const; 6357 6358 if (DiagID) { 6359 SourceLocation ErrLoc = Loc; 6360 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6361 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6362 Diag(ErrLoc, DiagID); 6363 Mutable = false; 6364 InvalidDecl = true; 6365 } 6366 } 6367 6368 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6369 BitWidth, Mutable); 6370 if (InvalidDecl) 6371 NewFD->setInvalidDecl(); 6372 6373 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6374 Diag(Loc, diag::err_duplicate_member) << II; 6375 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6376 NewFD->setInvalidDecl(); 6377 } 6378 6379 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6380 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6381 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6382 if (RDecl->getDefinition()) { 6383 // C++ 9.5p1: An object of a class with a non-trivial 6384 // constructor, a non-trivial copy constructor, a non-trivial 6385 // destructor, or a non-trivial copy assignment operator 6386 // cannot be a member of a union, nor can an array of such 6387 // objects. 6388 // TODO: C++0x alters this restriction significantly. 6389 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6390 NewFD->setInvalidDecl(); 6391 } 6392 } 6393 } 6394 6395 // FIXME: We need to pass in the attributes given an AST 6396 // representation, not a parser representation. 6397 if (D) 6398 // FIXME: What to pass instead of TUScope? 6399 ProcessDeclAttributes(TUScope, NewFD, *D); 6400 6401 if (T.isObjCGCWeak()) 6402 Diag(Loc, diag::warn_attribute_weak_on_field); 6403 6404 NewFD->setAccess(AS); 6405 return NewFD; 6406} 6407 6408bool Sema::CheckNontrivialField(FieldDecl *FD) { 6409 assert(FD); 6410 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6411 6412 if (FD->isInvalidDecl()) 6413 return true; 6414 6415 QualType EltTy = Context.getBaseElementType(FD->getType()); 6416 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6417 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6418 if (RDecl->getDefinition()) { 6419 // We check for copy constructors before constructors 6420 // because otherwise we'll never get complaints about 6421 // copy constructors. 6422 6423 CXXSpecialMember member = CXXInvalid; 6424 if (!RDecl->hasTrivialCopyConstructor()) 6425 member = CXXCopyConstructor; 6426 else if (!RDecl->hasTrivialConstructor()) 6427 member = CXXConstructor; 6428 else if (!RDecl->hasTrivialCopyAssignment()) 6429 member = CXXCopyAssignment; 6430 else if (!RDecl->hasTrivialDestructor()) 6431 member = CXXDestructor; 6432 6433 if (member != CXXInvalid) { 6434 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6435 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6436 DiagnoseNontrivial(RT, member); 6437 return true; 6438 } 6439 } 6440 } 6441 6442 return false; 6443} 6444 6445/// DiagnoseNontrivial - Given that a class has a non-trivial 6446/// special member, figure out why. 6447void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6448 QualType QT(T, 0U); 6449 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6450 6451 // Check whether the member was user-declared. 6452 switch (member) { 6453 case CXXInvalid: 6454 break; 6455 6456 case CXXConstructor: 6457 if (RD->hasUserDeclaredConstructor()) { 6458 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6459 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6460 const FunctionDecl *body = 0; 6461 ci->hasBody(body); 6462 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6463 SourceLocation CtorLoc = ci->getLocation(); 6464 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6465 return; 6466 } 6467 } 6468 6469 assert(0 && "found no user-declared constructors"); 6470 return; 6471 } 6472 break; 6473 6474 case CXXCopyConstructor: 6475 if (RD->hasUserDeclaredCopyConstructor()) { 6476 SourceLocation CtorLoc = 6477 RD->getCopyConstructor(Context, 0)->getLocation(); 6478 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6479 return; 6480 } 6481 break; 6482 6483 case CXXCopyAssignment: 6484 if (RD->hasUserDeclaredCopyAssignment()) { 6485 // FIXME: this should use the location of the copy 6486 // assignment, not the type. 6487 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6488 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6489 return; 6490 } 6491 break; 6492 6493 case CXXDestructor: 6494 if (RD->hasUserDeclaredDestructor()) { 6495 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6496 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6497 return; 6498 } 6499 break; 6500 } 6501 6502 typedef CXXRecordDecl::base_class_iterator base_iter; 6503 6504 // Virtual bases and members inhibit trivial copying/construction, 6505 // but not trivial destruction. 6506 if (member != CXXDestructor) { 6507 // Check for virtual bases. vbases includes indirect virtual bases, 6508 // so we just iterate through the direct bases. 6509 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6510 if (bi->isVirtual()) { 6511 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6512 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6513 return; 6514 } 6515 6516 // Check for virtual methods. 6517 typedef CXXRecordDecl::method_iterator meth_iter; 6518 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6519 ++mi) { 6520 if (mi->isVirtual()) { 6521 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6522 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6523 return; 6524 } 6525 } 6526 } 6527 6528 bool (CXXRecordDecl::*hasTrivial)() const; 6529 switch (member) { 6530 case CXXConstructor: 6531 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6532 case CXXCopyConstructor: 6533 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6534 case CXXCopyAssignment: 6535 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6536 case CXXDestructor: 6537 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6538 default: 6539 assert(0 && "unexpected special member"); return; 6540 } 6541 6542 // Check for nontrivial bases (and recurse). 6543 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6544 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6545 assert(BaseRT && "Don't know how to handle dependent bases"); 6546 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6547 if (!(BaseRecTy->*hasTrivial)()) { 6548 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6549 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6550 DiagnoseNontrivial(BaseRT, member); 6551 return; 6552 } 6553 } 6554 6555 // Check for nontrivial members (and recurse). 6556 typedef RecordDecl::field_iterator field_iter; 6557 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6558 ++fi) { 6559 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6560 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6561 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6562 6563 if (!(EltRD->*hasTrivial)()) { 6564 SourceLocation FLoc = (*fi)->getLocation(); 6565 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6566 DiagnoseNontrivial(EltRT, member); 6567 return; 6568 } 6569 } 6570 } 6571 6572 assert(0 && "found no explanation for non-trivial member"); 6573} 6574 6575/// TranslateIvarVisibility - Translate visibility from a token ID to an 6576/// AST enum value. 6577static ObjCIvarDecl::AccessControl 6578TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6579 switch (ivarVisibility) { 6580 default: assert(0 && "Unknown visitibility kind"); 6581 case tok::objc_private: return ObjCIvarDecl::Private; 6582 case tok::objc_public: return ObjCIvarDecl::Public; 6583 case tok::objc_protected: return ObjCIvarDecl::Protected; 6584 case tok::objc_package: return ObjCIvarDecl::Package; 6585 } 6586} 6587 6588/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6589/// in order to create an IvarDecl object for it. 6590Decl *Sema::ActOnIvar(Scope *S, 6591 SourceLocation DeclStart, 6592 Decl *IntfDecl, 6593 Declarator &D, ExprTy *BitfieldWidth, 6594 tok::ObjCKeywordKind Visibility) { 6595 6596 IdentifierInfo *II = D.getIdentifier(); 6597 Expr *BitWidth = (Expr*)BitfieldWidth; 6598 SourceLocation Loc = DeclStart; 6599 if (II) Loc = D.getIdentifierLoc(); 6600 6601 // FIXME: Unnamed fields can be handled in various different ways, for 6602 // example, unnamed unions inject all members into the struct namespace! 6603 6604 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6605 QualType T = TInfo->getType(); 6606 6607 if (BitWidth) { 6608 // 6.7.2.1p3, 6.7.2.1p4 6609 if (VerifyBitField(Loc, II, T, BitWidth)) { 6610 D.setInvalidType(); 6611 BitWidth = 0; 6612 } 6613 } else { 6614 // Not a bitfield. 6615 6616 // validate II. 6617 6618 } 6619 if (T->isReferenceType()) { 6620 Diag(Loc, diag::err_ivar_reference_type); 6621 D.setInvalidType(); 6622 } 6623 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6624 // than a variably modified type. 6625 else if (T->isVariablyModifiedType()) { 6626 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6627 D.setInvalidType(); 6628 } 6629 6630 // Get the visibility (access control) for this ivar. 6631 ObjCIvarDecl::AccessControl ac = 6632 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6633 : ObjCIvarDecl::None; 6634 // Must set ivar's DeclContext to its enclosing interface. 6635 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6636 ObjCContainerDecl *EnclosingContext; 6637 if (ObjCImplementationDecl *IMPDecl = 6638 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6639 if (!LangOpts.ObjCNonFragileABI2) { 6640 // Case of ivar declared in an implementation. Context is that of its class. 6641 EnclosingContext = IMPDecl->getClassInterface(); 6642 assert(EnclosingContext && "Implementation has no class interface!"); 6643 } 6644 else 6645 EnclosingContext = EnclosingDecl; 6646 } else { 6647 if (ObjCCategoryDecl *CDecl = 6648 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6649 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6650 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6651 return 0; 6652 } 6653 } 6654 EnclosingContext = EnclosingDecl; 6655 } 6656 6657 // Construct the decl. 6658 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6659 EnclosingContext, Loc, II, T, 6660 TInfo, ac, (Expr *)BitfieldWidth); 6661 6662 if (II) { 6663 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6664 ForRedeclaration); 6665 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6666 && !isa<TagDecl>(PrevDecl)) { 6667 Diag(Loc, diag::err_duplicate_member) << II; 6668 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6669 NewID->setInvalidDecl(); 6670 } 6671 } 6672 6673 // Process attributes attached to the ivar. 6674 ProcessDeclAttributes(S, NewID, D); 6675 6676 if (D.isInvalidType()) 6677 NewID->setInvalidDecl(); 6678 6679 if (II) { 6680 // FIXME: When interfaces are DeclContexts, we'll need to add 6681 // these to the interface. 6682 S->AddDecl(NewID); 6683 IdResolver.AddDecl(NewID); 6684 } 6685 6686 return NewID; 6687} 6688 6689/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6690/// class and class extensions. For every class @interface and class 6691/// extension @interface, if the last ivar is a bitfield of any type, 6692/// then add an implicit `char :0` ivar to the end of that interface. 6693void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6694 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6695 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6696 return; 6697 6698 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6699 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6700 6701 if (!Ivar->isBitField()) 6702 return; 6703 uint64_t BitFieldSize = 6704 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6705 if (BitFieldSize == 0) 6706 return; 6707 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6708 if (!ID) { 6709 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6710 if (!CD->IsClassExtension()) 6711 return; 6712 } 6713 // No need to add this to end of @implementation. 6714 else 6715 return; 6716 } 6717 // All conditions are met. Add a new bitfield to the tail end of ivars. 6718 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6719 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 6720 6721 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6722 DeclLoc, 0, 6723 Context.CharTy, 6724 Context.CreateTypeSourceInfo(Context.CharTy), 6725 ObjCIvarDecl::Private, BW, 6726 true); 6727 AllIvarDecls.push_back(Ivar); 6728} 6729 6730void Sema::ActOnFields(Scope* S, 6731 SourceLocation RecLoc, Decl *EnclosingDecl, 6732 Decl **Fields, unsigned NumFields, 6733 SourceLocation LBrac, SourceLocation RBrac, 6734 AttributeList *Attr) { 6735 assert(EnclosingDecl && "missing record or interface decl"); 6736 6737 // If the decl this is being inserted into is invalid, then it may be a 6738 // redeclaration or some other bogus case. Don't try to add fields to it. 6739 if (EnclosingDecl->isInvalidDecl()) { 6740 // FIXME: Deallocate fields? 6741 return; 6742 } 6743 6744 6745 // Verify that all the fields are okay. 6746 unsigned NumNamedMembers = 0; 6747 llvm::SmallVector<FieldDecl*, 32> RecFields; 6748 6749 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6750 for (unsigned i = 0; i != NumFields; ++i) { 6751 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6752 6753 // Get the type for the field. 6754 Type *FDTy = FD->getType().getTypePtr(); 6755 6756 if (!FD->isAnonymousStructOrUnion()) { 6757 // Remember all fields written by the user. 6758 RecFields.push_back(FD); 6759 } 6760 6761 // If the field is already invalid for some reason, don't emit more 6762 // diagnostics about it. 6763 if (FD->isInvalidDecl()) { 6764 EnclosingDecl->setInvalidDecl(); 6765 continue; 6766 } 6767 6768 // C99 6.7.2.1p2: 6769 // A structure or union shall not contain a member with 6770 // incomplete or function type (hence, a structure shall not 6771 // contain an instance of itself, but may contain a pointer to 6772 // an instance of itself), except that the last member of a 6773 // structure with more than one named member may have incomplete 6774 // array type; such a structure (and any union containing, 6775 // possibly recursively, a member that is such a structure) 6776 // shall not be a member of a structure or an element of an 6777 // array. 6778 if (FDTy->isFunctionType()) { 6779 // Field declared as a function. 6780 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6781 << FD->getDeclName(); 6782 FD->setInvalidDecl(); 6783 EnclosingDecl->setInvalidDecl(); 6784 continue; 6785 } else if (FDTy->isIncompleteArrayType() && Record && 6786 ((i == NumFields - 1 && !Record->isUnion()) || 6787 (getLangOptions().Microsoft && 6788 (i == NumFields - 1 || Record->isUnion())))) { 6789 // Flexible array member. 6790 // Microsoft is more permissive regarding flexible array. 6791 // It will accept flexible array in union and also 6792 // as the sole element of a struct/class. 6793 if (getLangOptions().Microsoft) { 6794 if (Record->isUnion()) 6795 Diag(FD->getLocation(), diag::ext_flexible_array_union) 6796 << FD->getDeclName(); 6797 else if (NumFields == 1) 6798 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 6799 << FD->getDeclName() << Record->getTagKind(); 6800 } else if (NumNamedMembers < 1) { 6801 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6802 << FD->getDeclName(); 6803 FD->setInvalidDecl(); 6804 EnclosingDecl->setInvalidDecl(); 6805 continue; 6806 } 6807 if (!FD->getType()->isDependentType() && 6808 !Context.getBaseElementType(FD->getType())->isPODType()) { 6809 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6810 << FD->getDeclName() << FD->getType(); 6811 FD->setInvalidDecl(); 6812 EnclosingDecl->setInvalidDecl(); 6813 continue; 6814 } 6815 // Okay, we have a legal flexible array member at the end of the struct. 6816 if (Record) 6817 Record->setHasFlexibleArrayMember(true); 6818 } else if (!FDTy->isDependentType() && 6819 RequireCompleteType(FD->getLocation(), FD->getType(), 6820 diag::err_field_incomplete)) { 6821 // Incomplete type 6822 FD->setInvalidDecl(); 6823 EnclosingDecl->setInvalidDecl(); 6824 continue; 6825 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6826 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6827 // If this is a member of a union, then entire union becomes "flexible". 6828 if (Record && Record->isUnion()) { 6829 Record->setHasFlexibleArrayMember(true); 6830 } else { 6831 // If this is a struct/class and this is not the last element, reject 6832 // it. Note that GCC supports variable sized arrays in the middle of 6833 // structures. 6834 if (i != NumFields-1) 6835 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6836 << FD->getDeclName() << FD->getType(); 6837 else { 6838 // We support flexible arrays at the end of structs in 6839 // other structs as an extension. 6840 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6841 << FD->getDeclName(); 6842 if (Record) 6843 Record->setHasFlexibleArrayMember(true); 6844 } 6845 } 6846 } 6847 if (Record && FDTTy->getDecl()->hasObjectMember()) 6848 Record->setHasObjectMember(true); 6849 } else if (FDTy->isObjCObjectType()) { 6850 /// A field cannot be an Objective-c object 6851 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6852 FD->setInvalidDecl(); 6853 EnclosingDecl->setInvalidDecl(); 6854 continue; 6855 } else if (getLangOptions().ObjC1 && 6856 getLangOptions().getGCMode() != LangOptions::NonGC && 6857 Record && 6858 (FD->getType()->isObjCObjectPointerType() || 6859 FD->getType().isObjCGCStrong())) 6860 Record->setHasObjectMember(true); 6861 else if (Context.getAsArrayType(FD->getType())) { 6862 QualType BaseType = Context.getBaseElementType(FD->getType()); 6863 if (Record && BaseType->isRecordType() && 6864 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6865 Record->setHasObjectMember(true); 6866 } 6867 // Keep track of the number of named members. 6868 if (FD->getIdentifier()) 6869 ++NumNamedMembers; 6870 } 6871 6872 // Okay, we successfully defined 'Record'. 6873 if (Record) { 6874 bool Completed = false; 6875 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 6876 if (!CXXRecord->isInvalidDecl()) { 6877 // Set access bits correctly on the directly-declared conversions. 6878 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 6879 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 6880 I != E; ++I) 6881 Convs->setAccess(I, (*I)->getAccess()); 6882 6883 if (!CXXRecord->isDependentType()) { 6884 // Add any implicitly-declared members to this class. 6885 AddImplicitlyDeclaredMembersToClass(CXXRecord); 6886 6887 // If we have virtual base classes, we may end up finding multiple 6888 // final overriders for a given virtual function. Check for this 6889 // problem now. 6890 if (CXXRecord->getNumVBases()) { 6891 CXXFinalOverriderMap FinalOverriders; 6892 CXXRecord->getFinalOverriders(FinalOverriders); 6893 6894 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 6895 MEnd = FinalOverriders.end(); 6896 M != MEnd; ++M) { 6897 for (OverridingMethods::iterator SO = M->second.begin(), 6898 SOEnd = M->second.end(); 6899 SO != SOEnd; ++SO) { 6900 assert(SO->second.size() > 0 && 6901 "Virtual function without overridding functions?"); 6902 if (SO->second.size() == 1) 6903 continue; 6904 6905 // C++ [class.virtual]p2: 6906 // In a derived class, if a virtual member function of a base 6907 // class subobject has more than one final overrider the 6908 // program is ill-formed. 6909 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 6910 << (NamedDecl *)M->first << Record; 6911 Diag(M->first->getLocation(), 6912 diag::note_overridden_virtual_function); 6913 for (OverridingMethods::overriding_iterator 6914 OM = SO->second.begin(), 6915 OMEnd = SO->second.end(); 6916 OM != OMEnd; ++OM) 6917 Diag(OM->Method->getLocation(), diag::note_final_overrider) 6918 << (NamedDecl *)M->first << OM->Method->getParent(); 6919 6920 Record->setInvalidDecl(); 6921 } 6922 } 6923 CXXRecord->completeDefinition(&FinalOverriders); 6924 Completed = true; 6925 } 6926 } 6927 } 6928 } 6929 6930 if (!Completed) 6931 Record->completeDefinition(); 6932 } else { 6933 ObjCIvarDecl **ClsFields = 6934 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6935 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6936 ID->setLocEnd(RBrac); 6937 // Add ivar's to class's DeclContext. 6938 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6939 ClsFields[i]->setLexicalDeclContext(ID); 6940 ID->addDecl(ClsFields[i]); 6941 } 6942 // Must enforce the rule that ivars in the base classes may not be 6943 // duplicates. 6944 if (ID->getSuperClass()) 6945 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6946 } else if (ObjCImplementationDecl *IMPDecl = 6947 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6948 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6949 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6950 // Ivar declared in @implementation never belongs to the implementation. 6951 // Only it is in implementation's lexical context. 6952 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6953 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6954 } else if (ObjCCategoryDecl *CDecl = 6955 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6956 // case of ivars in class extension; all other cases have been 6957 // reported as errors elsewhere. 6958 // FIXME. Class extension does not have a LocEnd field. 6959 // CDecl->setLocEnd(RBrac); 6960 // Add ivar's to class extension's DeclContext. 6961 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6962 ClsFields[i]->setLexicalDeclContext(CDecl); 6963 CDecl->addDecl(ClsFields[i]); 6964 } 6965 } 6966 } 6967 6968 if (Attr) 6969 ProcessDeclAttributeList(S, Record, Attr); 6970 6971 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6972 // set the visibility of this record. 6973 if (Record && !Record->getDeclContext()->isRecord()) 6974 AddPushedVisibilityAttribute(Record); 6975} 6976 6977/// \brief Determine whether the given integral value is representable within 6978/// the given type T. 6979static bool isRepresentableIntegerValue(ASTContext &Context, 6980 llvm::APSInt &Value, 6981 QualType T) { 6982 assert(T->isIntegralType(Context) && "Integral type required!"); 6983 unsigned BitWidth = Context.getIntWidth(T); 6984 6985 if (Value.isUnsigned() || Value.isNonNegative()) { 6986 if (T->isSignedIntegerType()) 6987 --BitWidth; 6988 return Value.getActiveBits() <= BitWidth; 6989 } 6990 return Value.getMinSignedBits() <= BitWidth; 6991} 6992 6993// \brief Given an integral type, return the next larger integral type 6994// (or a NULL type of no such type exists). 6995static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6996 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6997 // enum checking below. 6998 assert(T->isIntegralType(Context) && "Integral type required!"); 6999 const unsigned NumTypes = 4; 7000 QualType SignedIntegralTypes[NumTypes] = { 7001 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 7002 }; 7003 QualType UnsignedIntegralTypes[NumTypes] = { 7004 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 7005 Context.UnsignedLongLongTy 7006 }; 7007 7008 unsigned BitWidth = Context.getTypeSize(T); 7009 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 7010 : UnsignedIntegralTypes; 7011 for (unsigned I = 0; I != NumTypes; ++I) 7012 if (Context.getTypeSize(Types[I]) > BitWidth) 7013 return Types[I]; 7014 7015 return QualType(); 7016} 7017 7018EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 7019 EnumConstantDecl *LastEnumConst, 7020 SourceLocation IdLoc, 7021 IdentifierInfo *Id, 7022 Expr *Val) { 7023 unsigned IntWidth = Context.Target.getIntWidth(); 7024 llvm::APSInt EnumVal(IntWidth); 7025 QualType EltTy; 7026 if (Val) { 7027 if (Enum->isDependentType() || Val->isTypeDependent()) 7028 EltTy = Context.DependentTy; 7029 else { 7030 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 7031 SourceLocation ExpLoc; 7032 if (!Val->isValueDependent() && 7033 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7034 Val = 0; 7035 } else { 7036 if (!getLangOptions().CPlusPlus) { 7037 // C99 6.7.2.2p2: 7038 // The expression that defines the value of an enumeration constant 7039 // shall be an integer constant expression that has a value 7040 // representable as an int. 7041 7042 // Complain if the value is not representable in an int. 7043 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7044 Diag(IdLoc, diag::ext_enum_value_not_int) 7045 << EnumVal.toString(10) << Val->getSourceRange() 7046 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7047 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7048 // Force the type of the expression to 'int'. 7049 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 7050 } 7051 } 7052 7053 if (Enum->isFixed()) { 7054 EltTy = Enum->getIntegerType(); 7055 7056 // C++0x [dcl.enum]p5: 7057 // ... if the initializing value of an enumerator cannot be 7058 // represented by the underlying type, the program is ill-formed. 7059 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) 7060 Diag(IdLoc, diag::err_enumerator_too_large) 7061 << EltTy; 7062 else 7063 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7064 } 7065 else { 7066 // C++0x [dcl.enum]p5: 7067 // If the underlying type is not fixed, the type of each enumerator 7068 // is the type of its initializing value: 7069 // - If an initializer is specified for an enumerator, the 7070 // initializing value has the same type as the expression. 7071 EltTy = Val->getType(); 7072 } 7073 } 7074 } 7075 } 7076 7077 if (!Val) { 7078 if (Enum->isDependentType()) 7079 EltTy = Context.DependentTy; 7080 else if (!LastEnumConst) { 7081 // C++0x [dcl.enum]p5: 7082 // If the underlying type is not fixed, the type of each enumerator 7083 // is the type of its initializing value: 7084 // - If no initializer is specified for the first enumerator, the 7085 // initializing value has an unspecified integral type. 7086 // 7087 // GCC uses 'int' for its unspecified integral type, as does 7088 // C99 6.7.2.2p3. 7089 if (Enum->isFixed()) { 7090 EltTy = Enum->getIntegerType(); 7091 } 7092 else { 7093 EltTy = Context.IntTy; 7094 } 7095 } else { 7096 // Assign the last value + 1. 7097 EnumVal = LastEnumConst->getInitVal(); 7098 ++EnumVal; 7099 EltTy = LastEnumConst->getType(); 7100 7101 // Check for overflow on increment. 7102 if (EnumVal < LastEnumConst->getInitVal()) { 7103 // C++0x [dcl.enum]p5: 7104 // If the underlying type is not fixed, the type of each enumerator 7105 // is the type of its initializing value: 7106 // 7107 // - Otherwise the type of the initializing value is the same as 7108 // the type of the initializing value of the preceding enumerator 7109 // unless the incremented value is not representable in that type, 7110 // in which case the type is an unspecified integral type 7111 // sufficient to contain the incremented value. If no such type 7112 // exists, the program is ill-formed. 7113 QualType T = getNextLargerIntegralType(Context, EltTy); 7114 if (T.isNull() || Enum->isFixed()) { 7115 // There is no integral type larger enough to represent this 7116 // value. Complain, then allow the value to wrap around. 7117 EnumVal = LastEnumConst->getInitVal(); 7118 EnumVal.zext(EnumVal.getBitWidth() * 2); 7119 ++EnumVal; 7120 if (Enum->isFixed()) 7121 // When the underlying type is fixed, this is ill-formed. 7122 Diag(IdLoc, diag::err_enumerator_wrapped) 7123 << EnumVal.toString(10) 7124 << EltTy; 7125 else 7126 Diag(IdLoc, diag::warn_enumerator_too_large) 7127 << EnumVal.toString(10); 7128 } else { 7129 EltTy = T; 7130 } 7131 7132 // Retrieve the last enumerator's value, extent that type to the 7133 // type that is supposed to be large enough to represent the incremented 7134 // value, then increment. 7135 EnumVal = LastEnumConst->getInitVal(); 7136 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7137 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7138 ++EnumVal; 7139 7140 // If we're not in C++, diagnose the overflow of enumerator values, 7141 // which in C99 means that the enumerator value is not representable in 7142 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7143 // permits enumerator values that are representable in some larger 7144 // integral type. 7145 if (!getLangOptions().CPlusPlus && !T.isNull()) 7146 Diag(IdLoc, diag::warn_enum_value_overflow); 7147 } else if (!getLangOptions().CPlusPlus && 7148 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7149 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7150 Diag(IdLoc, diag::ext_enum_value_not_int) 7151 << EnumVal.toString(10) << 1; 7152 } 7153 } 7154 } 7155 7156 if (!EltTy->isDependentType()) { 7157 // Make the enumerator value match the signedness and size of the 7158 // enumerator's type. 7159 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7160 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7161 } 7162 7163 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7164 Val, EnumVal); 7165} 7166 7167 7168Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 7169 Decl *lastEnumConst, 7170 SourceLocation IdLoc, 7171 IdentifierInfo *Id, 7172 SourceLocation EqualLoc, ExprTy *val) { 7173 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7174 EnumConstantDecl *LastEnumConst = 7175 cast_or_null<EnumConstantDecl>(lastEnumConst); 7176 Expr *Val = static_cast<Expr*>(val); 7177 7178 // The scope passed in may not be a decl scope. Zip up the scope tree until 7179 // we find one that is. 7180 S = getNonFieldDeclScope(S); 7181 7182 // Verify that there isn't already something declared with this name in this 7183 // scope. 7184 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7185 ForRedeclaration); 7186 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7187 // Maybe we will complain about the shadowed template parameter. 7188 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7189 // Just pretend that we didn't see the previous declaration. 7190 PrevDecl = 0; 7191 } 7192 7193 if (PrevDecl) { 7194 // When in C++, we may get a TagDecl with the same name; in this case the 7195 // enum constant will 'hide' the tag. 7196 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7197 "Received TagDecl when not in C++!"); 7198 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7199 if (isa<EnumConstantDecl>(PrevDecl)) 7200 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7201 else 7202 Diag(IdLoc, diag::err_redefinition) << Id; 7203 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7204 return 0; 7205 } 7206 } 7207 7208 // C++ [class.mem]p13: 7209 // If T is the name of a class, then each of the following shall have a 7210 // name different from T: 7211 // - every enumerator of every member of class T that is an enumerated 7212 // type 7213 if (CXXRecordDecl *Record 7214 = dyn_cast<CXXRecordDecl>( 7215 TheEnumDecl->getDeclContext()->getRedeclContext())) 7216 if (Record->getIdentifier() && Record->getIdentifier() == Id) 7217 Diag(IdLoc, diag::err_member_name_of_class) << Id; 7218 7219 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 7220 IdLoc, Id, Val); 7221 7222 // Register this decl in the current scope stack. 7223 if (New) { 7224 New->setAccess(TheEnumDecl->getAccess()); 7225 PushOnScopeChains(New, S); 7226 } 7227 7228 return New; 7229} 7230 7231void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7232 SourceLocation RBraceLoc, Decl *EnumDeclX, 7233 Decl **Elements, unsigned NumElements, 7234 Scope *S, AttributeList *Attr) { 7235 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7236 QualType EnumType = Context.getTypeDeclType(Enum); 7237 7238 if (Attr) 7239 ProcessDeclAttributeList(S, Enum, Attr); 7240 7241 if (Enum->isDependentType()) { 7242 for (unsigned i = 0; i != NumElements; ++i) { 7243 EnumConstantDecl *ECD = 7244 cast_or_null<EnumConstantDecl>(Elements[i]); 7245 if (!ECD) continue; 7246 7247 ECD->setType(EnumType); 7248 } 7249 7250 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7251 return; 7252 } 7253 7254 // TODO: If the result value doesn't fit in an int, it must be a long or long 7255 // long value. ISO C does not support this, but GCC does as an extension, 7256 // emit a warning. 7257 unsigned IntWidth = Context.Target.getIntWidth(); 7258 unsigned CharWidth = Context.Target.getCharWidth(); 7259 unsigned ShortWidth = Context.Target.getShortWidth(); 7260 7261 // Verify that all the values are okay, compute the size of the values, and 7262 // reverse the list. 7263 unsigned NumNegativeBits = 0; 7264 unsigned NumPositiveBits = 0; 7265 7266 // Keep track of whether all elements have type int. 7267 bool AllElementsInt = true; 7268 7269 for (unsigned i = 0; i != NumElements; ++i) { 7270 EnumConstantDecl *ECD = 7271 cast_or_null<EnumConstantDecl>(Elements[i]); 7272 if (!ECD) continue; // Already issued a diagnostic. 7273 7274 const llvm::APSInt &InitVal = ECD->getInitVal(); 7275 7276 // Keep track of the size of positive and negative values. 7277 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7278 NumPositiveBits = std::max(NumPositiveBits, 7279 (unsigned)InitVal.getActiveBits()); 7280 else 7281 NumNegativeBits = std::max(NumNegativeBits, 7282 (unsigned)InitVal.getMinSignedBits()); 7283 7284 // Keep track of whether every enum element has type int (very commmon). 7285 if (AllElementsInt) 7286 AllElementsInt = ECD->getType() == Context.IntTy; 7287 } 7288 7289 // Figure out the type that should be used for this enum. 7290 // FIXME: Support -fshort-enums. 7291 QualType BestType; 7292 unsigned BestWidth; 7293 7294 // C++0x N3000 [conv.prom]p3: 7295 // An rvalue of an unscoped enumeration type whose underlying 7296 // type is not fixed can be converted to an rvalue of the first 7297 // of the following types that can represent all the values of 7298 // the enumeration: int, unsigned int, long int, unsigned long 7299 // int, long long int, or unsigned long long int. 7300 // C99 6.4.4.3p2: 7301 // An identifier declared as an enumeration constant has type int. 7302 // The C99 rule is modified by a gcc extension 7303 QualType BestPromotionType; 7304 7305 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7306 // -fshort-enums is the equivalent to specifying the packed attribute on all 7307 // enum definitions. 7308 if (LangOpts.ShortEnums) 7309 Packed = true; 7310 7311 if (Enum->isFixed()) { 7312 BestType = BestPromotionType = Enum->getIntegerType(); 7313 // We don't need to set BestWidth, because BestType is going to be the type 7314 // of the enumerators, but we do anyway because otherwise some compilers 7315 // warn that it might be used uninitialized. 7316 BestWidth = CharWidth; 7317 } 7318 else if (NumNegativeBits) { 7319 // If there is a negative value, figure out the smallest integer type (of 7320 // int/long/longlong) that fits. 7321 // If it's packed, check also if it fits a char or a short. 7322 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7323 BestType = Context.SignedCharTy; 7324 BestWidth = CharWidth; 7325 } else if (Packed && NumNegativeBits <= ShortWidth && 7326 NumPositiveBits < ShortWidth) { 7327 BestType = Context.ShortTy; 7328 BestWidth = ShortWidth; 7329 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7330 BestType = Context.IntTy; 7331 BestWidth = IntWidth; 7332 } else { 7333 BestWidth = Context.Target.getLongWidth(); 7334 7335 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7336 BestType = Context.LongTy; 7337 } else { 7338 BestWidth = Context.Target.getLongLongWidth(); 7339 7340 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7341 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7342 BestType = Context.LongLongTy; 7343 } 7344 } 7345 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7346 } else { 7347 // If there is no negative value, figure out the smallest type that fits 7348 // all of the enumerator values. 7349 // If it's packed, check also if it fits a char or a short. 7350 if (Packed && NumPositiveBits <= CharWidth) { 7351 BestType = Context.UnsignedCharTy; 7352 BestPromotionType = Context.IntTy; 7353 BestWidth = CharWidth; 7354 } else if (Packed && NumPositiveBits <= ShortWidth) { 7355 BestType = Context.UnsignedShortTy; 7356 BestPromotionType = Context.IntTy; 7357 BestWidth = ShortWidth; 7358 } else if (NumPositiveBits <= IntWidth) { 7359 BestType = Context.UnsignedIntTy; 7360 BestWidth = IntWidth; 7361 BestPromotionType 7362 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7363 ? Context.UnsignedIntTy : Context.IntTy; 7364 } else if (NumPositiveBits <= 7365 (BestWidth = Context.Target.getLongWidth())) { 7366 BestType = Context.UnsignedLongTy; 7367 BestPromotionType 7368 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7369 ? Context.UnsignedLongTy : Context.LongTy; 7370 } else { 7371 BestWidth = Context.Target.getLongLongWidth(); 7372 assert(NumPositiveBits <= BestWidth && 7373 "How could an initializer get larger than ULL?"); 7374 BestType = Context.UnsignedLongLongTy; 7375 BestPromotionType 7376 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7377 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7378 } 7379 } 7380 7381 // Loop over all of the enumerator constants, changing their types to match 7382 // the type of the enum if needed. 7383 for (unsigned i = 0; i != NumElements; ++i) { 7384 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7385 if (!ECD) continue; // Already issued a diagnostic. 7386 7387 // Standard C says the enumerators have int type, but we allow, as an 7388 // extension, the enumerators to be larger than int size. If each 7389 // enumerator value fits in an int, type it as an int, otherwise type it the 7390 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7391 // that X has type 'int', not 'unsigned'. 7392 7393 // Determine whether the value fits into an int. 7394 llvm::APSInt InitVal = ECD->getInitVal(); 7395 7396 // If it fits into an integer type, force it. Otherwise force it to match 7397 // the enum decl type. 7398 QualType NewTy; 7399 unsigned NewWidth; 7400 bool NewSign; 7401 if (!getLangOptions().CPlusPlus && 7402 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7403 NewTy = Context.IntTy; 7404 NewWidth = IntWidth; 7405 NewSign = true; 7406 } else if (ECD->getType() == BestType) { 7407 // Already the right type! 7408 if (getLangOptions().CPlusPlus) 7409 // C++ [dcl.enum]p4: Following the closing brace of an 7410 // enum-specifier, each enumerator has the type of its 7411 // enumeration. 7412 ECD->setType(EnumType); 7413 continue; 7414 } else { 7415 NewTy = BestType; 7416 NewWidth = BestWidth; 7417 NewSign = BestType->isSignedIntegerType(); 7418 } 7419 7420 // Adjust the APSInt value. 7421 InitVal.extOrTrunc(NewWidth); 7422 InitVal.setIsSigned(NewSign); 7423 ECD->setInitVal(InitVal); 7424 7425 // Adjust the Expr initializer and type. 7426 if (ECD->getInitExpr()) 7427 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7428 CK_IntegralCast, 7429 ECD->getInitExpr(), 7430 /*base paths*/ 0, 7431 VK_RValue)); 7432 if (getLangOptions().CPlusPlus) 7433 // C++ [dcl.enum]p4: Following the closing brace of an 7434 // enum-specifier, each enumerator has the type of its 7435 // enumeration. 7436 ECD->setType(EnumType); 7437 else 7438 ECD->setType(NewTy); 7439 } 7440 7441 Enum->completeDefinition(BestType, BestPromotionType, 7442 NumPositiveBits, NumNegativeBits); 7443} 7444 7445Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7446 StringLiteral *AsmString = cast<StringLiteral>(expr); 7447 7448 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7449 Loc, AsmString); 7450 CurContext->addDecl(New); 7451 return New; 7452} 7453 7454void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7455 SourceLocation PragmaLoc, 7456 SourceLocation NameLoc) { 7457 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7458 7459 if (PrevDecl) { 7460 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7461 } else { 7462 (void)WeakUndeclaredIdentifiers.insert( 7463 std::pair<IdentifierInfo*,WeakInfo> 7464 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7465 } 7466} 7467 7468void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7469 IdentifierInfo* AliasName, 7470 SourceLocation PragmaLoc, 7471 SourceLocation NameLoc, 7472 SourceLocation AliasNameLoc) { 7473 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7474 LookupOrdinaryName); 7475 WeakInfo W = WeakInfo(Name, NameLoc); 7476 7477 if (PrevDecl) { 7478 if (!PrevDecl->hasAttr<AliasAttr>()) 7479 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7480 DeclApplyPragmaWeak(TUScope, ND, W); 7481 } else { 7482 (void)WeakUndeclaredIdentifiers.insert( 7483 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7484 } 7485} 7486