SemaDecl.cpp revision b6bbcc9995186799a60ce17d0c1acff31601653a
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 NamedDecl *New; 2305 2306 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2307 QualType R = TInfo->getType(); 2308 2309 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2310 ForRedeclaration); 2311 2312 // See if this is a redefinition of a variable in the same scope. 2313 if (!D.getCXXScopeSpec().isSet()) { 2314 bool IsLinkageLookup = false; 2315 2316 // If the declaration we're planning to build will be a function 2317 // or object with linkage, then look for another declaration with 2318 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2319 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2320 /* Do nothing*/; 2321 else if (R->isFunctionType()) { 2322 if (CurContext->isFunctionOrMethod() || 2323 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2324 IsLinkageLookup = true; 2325 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2326 IsLinkageLookup = true; 2327 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2328 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2329 IsLinkageLookup = true; 2330 2331 if (IsLinkageLookup) 2332 Previous.clear(LookupRedeclarationWithLinkage); 2333 2334 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2335 } else { // Something like "int foo::x;" 2336 LookupQualifiedName(Previous, DC); 2337 2338 // Don't consider using declarations as previous declarations for 2339 // out-of-line members. 2340 RemoveUsingDecls(Previous); 2341 2342 // C++ 7.3.1.2p2: 2343 // Members (including explicit specializations of templates) of a named 2344 // namespace can also be defined outside that namespace by explicit 2345 // qualification of the name being defined, provided that the entity being 2346 // defined was already declared in the namespace and the definition appears 2347 // after the point of declaration in a namespace that encloses the 2348 // declarations namespace. 2349 // 2350 // Note that we only check the context at this point. We don't yet 2351 // have enough information to make sure that PrevDecl is actually 2352 // the declaration we want to match. For example, given: 2353 // 2354 // class X { 2355 // void f(); 2356 // void f(float); 2357 // }; 2358 // 2359 // void X::f(int) { } // ill-formed 2360 // 2361 // In this case, PrevDecl will point to the overload set 2362 // containing the two f's declared in X, but neither of them 2363 // matches. 2364 2365 // First check whether we named the global scope. 2366 if (isa<TranslationUnitDecl>(DC)) { 2367 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2368 << Name << D.getCXXScopeSpec().getRange(); 2369 } else { 2370 DeclContext *Cur = CurContext; 2371 while (isa<LinkageSpecDecl>(Cur)) 2372 Cur = Cur->getParent(); 2373 if (!Cur->Encloses(DC)) { 2374 // The qualifying scope doesn't enclose the original declaration. 2375 // Emit diagnostic based on current scope. 2376 SourceLocation L = D.getIdentifierLoc(); 2377 SourceRange R = D.getCXXScopeSpec().getRange(); 2378 if (isa<FunctionDecl>(Cur)) 2379 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2380 else 2381 Diag(L, diag::err_invalid_declarator_scope) 2382 << Name << cast<NamedDecl>(DC) << R; 2383 D.setInvalidType(); 2384 } 2385 } 2386 } 2387 2388 if (Previous.isSingleResult() && 2389 Previous.getFoundDecl()->isTemplateParameter()) { 2390 // Maybe we will complain about the shadowed template parameter. 2391 if (!D.isInvalidType()) 2392 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2393 Previous.getFoundDecl())) 2394 D.setInvalidType(); 2395 2396 // Just pretend that we didn't see the previous declaration. 2397 Previous.clear(); 2398 } 2399 2400 // In C++, the previous declaration we find might be a tag type 2401 // (class or enum). In this case, the new declaration will hide the 2402 // tag type. Note that this does does not apply if we're declaring a 2403 // typedef (C++ [dcl.typedef]p4). 2404 if (Previous.isSingleTagDecl() && 2405 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2406 Previous.clear(); 2407 2408 bool Redeclaration = false; 2409 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2410 if (TemplateParamLists.size()) { 2411 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2412 return 0; 2413 } 2414 2415 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2416 } else if (R->isFunctionType()) { 2417 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2418 move(TemplateParamLists), 2419 IsFunctionDefinition, Redeclaration); 2420 } else { 2421 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2422 move(TemplateParamLists), 2423 Redeclaration); 2424 } 2425 2426 if (New == 0) 2427 return 0; 2428 2429 // If this has an identifier and is not an invalid redeclaration or 2430 // function template specialization, add it to the scope stack. 2431 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2432 PushOnScopeChains(New, S); 2433 2434 return New; 2435} 2436 2437/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2438/// types into constant array types in certain situations which would otherwise 2439/// be errors (for GCC compatibility). 2440static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2441 ASTContext &Context, 2442 bool &SizeIsNegative, 2443 llvm::APSInt &Oversized) { 2444 // This method tries to turn a variable array into a constant 2445 // array even when the size isn't an ICE. This is necessary 2446 // for compatibility with code that depends on gcc's buggy 2447 // constant expression folding, like struct {char x[(int)(char*)2];} 2448 SizeIsNegative = false; 2449 Oversized = 0; 2450 2451 if (T->isDependentType()) 2452 return QualType(); 2453 2454 QualifierCollector Qs; 2455 const Type *Ty = Qs.strip(T); 2456 2457 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2458 QualType Pointee = PTy->getPointeeType(); 2459 QualType FixedType = 2460 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2461 Oversized); 2462 if (FixedType.isNull()) return FixedType; 2463 FixedType = Context.getPointerType(FixedType); 2464 return Qs.apply(FixedType); 2465 } 2466 2467 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2468 if (!VLATy) 2469 return QualType(); 2470 // FIXME: We should probably handle this case 2471 if (VLATy->getElementType()->isVariablyModifiedType()) 2472 return QualType(); 2473 2474 Expr::EvalResult EvalResult; 2475 if (!VLATy->getSizeExpr() || 2476 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2477 !EvalResult.Val.isInt()) 2478 return QualType(); 2479 2480 // Check whether the array size is negative. 2481 llvm::APSInt &Res = EvalResult.Val.getInt(); 2482 if (Res.isSigned() && Res.isNegative()) { 2483 SizeIsNegative = true; 2484 return QualType(); 2485 } 2486 2487 // Check whether the array is too large to be addressed. 2488 unsigned ActiveSizeBits 2489 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2490 Res); 2491 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2492 Oversized = Res; 2493 return QualType(); 2494 } 2495 2496 return Context.getConstantArrayType(VLATy->getElementType(), 2497 Res, ArrayType::Normal, 0); 2498} 2499 2500/// \brief Register the given locally-scoped external C declaration so 2501/// that it can be found later for redeclarations 2502void 2503Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2504 const LookupResult &Previous, 2505 Scope *S) { 2506 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2507 "Decl is not a locally-scoped decl!"); 2508 // Note that we have a locally-scoped external with this name. 2509 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2510 2511 if (!Previous.isSingleResult()) 2512 return; 2513 2514 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2515 2516 // If there was a previous declaration of this variable, it may be 2517 // in our identifier chain. Update the identifier chain with the new 2518 // declaration. 2519 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2520 // The previous declaration was found on the identifer resolver 2521 // chain, so remove it from its scope. 2522 while (S && !S->isDeclScope(PrevDecl)) 2523 S = S->getParent(); 2524 2525 if (S) 2526 S->RemoveDecl(PrevDecl); 2527 } 2528} 2529 2530/// \brief Diagnose function specifiers on a declaration of an identifier that 2531/// does not identify a function. 2532void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2533 // FIXME: We should probably indicate the identifier in question to avoid 2534 // confusion for constructs like "inline int a(), b;" 2535 if (D.getDeclSpec().isInlineSpecified()) 2536 Diag(D.getDeclSpec().getInlineSpecLoc(), 2537 diag::err_inline_non_function); 2538 2539 if (D.getDeclSpec().isVirtualSpecified()) 2540 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2541 diag::err_virtual_non_function); 2542 2543 if (D.getDeclSpec().isExplicitSpecified()) 2544 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2545 diag::err_explicit_non_function); 2546} 2547 2548NamedDecl* 2549Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2550 QualType R, TypeSourceInfo *TInfo, 2551 LookupResult &Previous, bool &Redeclaration) { 2552 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2553 if (D.getCXXScopeSpec().isSet()) { 2554 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2555 << D.getCXXScopeSpec().getRange(); 2556 D.setInvalidType(); 2557 // Pretend we didn't see the scope specifier. 2558 DC = CurContext; 2559 Previous.clear(); 2560 } 2561 2562 if (getLangOptions().CPlusPlus) { 2563 // Check that there are no default arguments (C++ only). 2564 CheckExtraCXXDefaultArguments(D); 2565 } 2566 2567 DiagnoseFunctionSpecifiers(D); 2568 2569 if (D.getDeclSpec().isThreadSpecified()) 2570 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2571 2572 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2573 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2574 << D.getName().getSourceRange(); 2575 return 0; 2576 } 2577 2578 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2579 if (!NewTD) return 0; 2580 2581 // Handle attributes prior to checking for duplicates in MergeVarDecl 2582 ProcessDeclAttributes(S, NewTD, D); 2583 2584 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2585 // then it shall have block scope. 2586 // Note that variably modified types must be fixed before merging the decl so 2587 // that redeclarations will match. 2588 QualType T = NewTD->getUnderlyingType(); 2589 if (T->isVariablyModifiedType()) { 2590 getCurFunction()->setHasBranchProtectedScope(); 2591 2592 if (S->getFnParent() == 0) { 2593 bool SizeIsNegative; 2594 llvm::APSInt Oversized; 2595 QualType FixedTy = 2596 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2597 Oversized); 2598 if (!FixedTy.isNull()) { 2599 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2600 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2601 } else { 2602 if (SizeIsNegative) 2603 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2604 else if (T->isVariableArrayType()) 2605 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2606 else if (Oversized.getBoolValue()) 2607 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2608 << Oversized.toString(10); 2609 else 2610 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2611 NewTD->setInvalidDecl(); 2612 } 2613 } 2614 } 2615 2616 // Merge the decl with the existing one if appropriate. If the decl is 2617 // in an outer scope, it isn't the same thing. 2618 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2619 if (!Previous.empty()) { 2620 Redeclaration = true; 2621 MergeTypeDefDecl(NewTD, Previous); 2622 } 2623 2624 // If this is the C FILE type, notify the AST context. 2625 if (IdentifierInfo *II = NewTD->getIdentifier()) 2626 if (!NewTD->isInvalidDecl() && 2627 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2628 if (II->isStr("FILE")) 2629 Context.setFILEDecl(NewTD); 2630 else if (II->isStr("jmp_buf")) 2631 Context.setjmp_bufDecl(NewTD); 2632 else if (II->isStr("sigjmp_buf")) 2633 Context.setsigjmp_bufDecl(NewTD); 2634 else if (II->isStr("__builtin_va_list")) 2635 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2636 } 2637 2638 return NewTD; 2639} 2640 2641/// \brief Determines whether the given declaration is an out-of-scope 2642/// previous declaration. 2643/// 2644/// This routine should be invoked when name lookup has found a 2645/// previous declaration (PrevDecl) that is not in the scope where a 2646/// new declaration by the same name is being introduced. If the new 2647/// declaration occurs in a local scope, previous declarations with 2648/// linkage may still be considered previous declarations (C99 2649/// 6.2.2p4-5, C++ [basic.link]p6). 2650/// 2651/// \param PrevDecl the previous declaration found by name 2652/// lookup 2653/// 2654/// \param DC the context in which the new declaration is being 2655/// declared. 2656/// 2657/// \returns true if PrevDecl is an out-of-scope previous declaration 2658/// for a new delcaration with the same name. 2659static bool 2660isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2661 ASTContext &Context) { 2662 if (!PrevDecl) 2663 return false; 2664 2665 if (!PrevDecl->hasLinkage()) 2666 return false; 2667 2668 if (Context.getLangOptions().CPlusPlus) { 2669 // C++ [basic.link]p6: 2670 // If there is a visible declaration of an entity with linkage 2671 // having the same name and type, ignoring entities declared 2672 // outside the innermost enclosing namespace scope, the block 2673 // scope declaration declares that same entity and receives the 2674 // linkage of the previous declaration. 2675 DeclContext *OuterContext = DC->getRedeclContext(); 2676 if (!OuterContext->isFunctionOrMethod()) 2677 // This rule only applies to block-scope declarations. 2678 return false; 2679 2680 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2681 if (PrevOuterContext->isRecord()) 2682 // We found a member function: ignore it. 2683 return false; 2684 2685 // Find the innermost enclosing namespace for the new and 2686 // previous declarations. 2687 OuterContext = OuterContext->getEnclosingNamespaceContext(); 2688 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 2689 2690 // The previous declaration is in a different namespace, so it 2691 // isn't the same function. 2692 if (!OuterContext->Equals(PrevOuterContext)) 2693 return false; 2694 } 2695 2696 return true; 2697} 2698 2699static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2700 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2701 if (!SS.isSet()) return; 2702 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2703 SS.getRange()); 2704} 2705 2706NamedDecl* 2707Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 2708 QualType R, TypeSourceInfo *TInfo, 2709 LookupResult &Previous, 2710 MultiTemplateParamsArg TemplateParamLists, 2711 bool &Redeclaration) { 2712 DeclarationName Name = GetNameForDeclarator(D).getName(); 2713 2714 // Check that there are no default arguments (C++ only). 2715 if (getLangOptions().CPlusPlus) 2716 CheckExtraCXXDefaultArguments(D); 2717 2718 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2719 assert(SCSpec != DeclSpec::SCS_typedef && 2720 "Parser allowed 'typedef' as storage class VarDecl."); 2721 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2722 if (SCSpec == DeclSpec::SCS_mutable) { 2723 // mutable can only appear on non-static class members, so it's always 2724 // an error here 2725 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2726 D.setInvalidType(); 2727 SC = SC_None; 2728 } 2729 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2730 VarDecl::StorageClass SCAsWritten 2731 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2732 2733 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2734 if (!II) { 2735 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2736 << Name.getAsString(); 2737 return 0; 2738 } 2739 2740 DiagnoseFunctionSpecifiers(D); 2741 2742 if (!DC->isRecord() && S->getFnParent() == 0) { 2743 // C99 6.9p2: The storage-class specifiers auto and register shall not 2744 // appear in the declaration specifiers in an external declaration. 2745 if (SC == SC_Auto || SC == SC_Register) { 2746 2747 // If this is a register variable with an asm label specified, then this 2748 // is a GNU extension. 2749 if (SC == SC_Register && D.getAsmLabel()) 2750 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2751 else 2752 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2753 D.setInvalidType(); 2754 } 2755 } 2756 if (DC->isRecord() && !CurContext->isRecord()) { 2757 // This is an out-of-line definition of a static data member. 2758 if (SC == SC_Static) { 2759 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2760 diag::err_static_out_of_line) 2761 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2762 } else if (SC == SC_None) 2763 SC = SC_Static; 2764 } 2765 if (SC == SC_Static) { 2766 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2767 if (RD->isLocalClass()) 2768 Diag(D.getIdentifierLoc(), 2769 diag::err_static_data_member_not_allowed_in_local_class) 2770 << Name << RD->getDeclName(); 2771 } 2772 } 2773 2774 // Match up the template parameter lists with the scope specifier, then 2775 // determine whether we have a template or a template specialization. 2776 bool isExplicitSpecialization = false; 2777 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2778 bool Invalid = false; 2779 if (TemplateParameterList *TemplateParams 2780 = MatchTemplateParametersToScopeSpecifier( 2781 D.getDeclSpec().getSourceRange().getBegin(), 2782 D.getCXXScopeSpec(), 2783 (TemplateParameterList**)TemplateParamLists.get(), 2784 TemplateParamLists.size(), 2785 /*never a friend*/ false, 2786 isExplicitSpecialization, 2787 Invalid)) { 2788 // All but one template parameter lists have been matching. 2789 --NumMatchedTemplateParamLists; 2790 2791 if (TemplateParams->size() > 0) { 2792 // There is no such thing as a variable template. 2793 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2794 << II 2795 << SourceRange(TemplateParams->getTemplateLoc(), 2796 TemplateParams->getRAngleLoc()); 2797 return 0; 2798 } else { 2799 // There is an extraneous 'template<>' for this variable. Complain 2800 // about it, but allow the declaration of the variable. 2801 Diag(TemplateParams->getTemplateLoc(), 2802 diag::err_template_variable_noparams) 2803 << II 2804 << SourceRange(TemplateParams->getTemplateLoc(), 2805 TemplateParams->getRAngleLoc()); 2806 2807 isExplicitSpecialization = true; 2808 } 2809 } 2810 2811 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2812 II, R, TInfo, SC, SCAsWritten); 2813 2814 if (D.isInvalidType() || Invalid) 2815 NewVD->setInvalidDecl(); 2816 2817 SetNestedNameSpecifier(NewVD, D); 2818 2819 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2820 NewVD->setTemplateParameterListsInfo(Context, 2821 NumMatchedTemplateParamLists, 2822 (TemplateParameterList**)TemplateParamLists.release()); 2823 } 2824 2825 if (D.getDeclSpec().isThreadSpecified()) { 2826 if (NewVD->hasLocalStorage()) 2827 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2828 else if (!Context.Target.isTLSSupported()) 2829 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2830 else 2831 NewVD->setThreadSpecified(true); 2832 } 2833 2834 // Set the lexical context. If the declarator has a C++ scope specifier, the 2835 // lexical context will be different from the semantic context. 2836 NewVD->setLexicalDeclContext(CurContext); 2837 2838 // Handle attributes prior to checking for duplicates in MergeVarDecl 2839 ProcessDeclAttributes(S, NewVD, D); 2840 2841 // Handle GNU asm-label extension (encoded as an attribute). 2842 if (Expr *E = (Expr*)D.getAsmLabel()) { 2843 // The parser guarantees this is a string. 2844 StringLiteral *SE = cast<StringLiteral>(E); 2845 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2846 Context, SE->getString())); 2847 } 2848 2849 // Diagnose shadowed variables before filtering for scope. 2850 if (!D.getCXXScopeSpec().isSet()) 2851 CheckShadow(S, NewVD, Previous); 2852 2853 // Don't consider existing declarations that are in a different 2854 // scope and are out-of-semantic-context declarations (if the new 2855 // declaration has linkage). 2856 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2857 2858 // Merge the decl with the existing one if appropriate. 2859 if (!Previous.empty()) { 2860 if (Previous.isSingleResult() && 2861 isa<FieldDecl>(Previous.getFoundDecl()) && 2862 D.getCXXScopeSpec().isSet()) { 2863 // The user tried to define a non-static data member 2864 // out-of-line (C++ [dcl.meaning]p1). 2865 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2866 << D.getCXXScopeSpec().getRange(); 2867 Previous.clear(); 2868 NewVD->setInvalidDecl(); 2869 } 2870 } else if (D.getCXXScopeSpec().isSet()) { 2871 // No previous declaration in the qualifying scope. 2872 Diag(D.getIdentifierLoc(), diag::err_no_member) 2873 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2874 << D.getCXXScopeSpec().getRange(); 2875 NewVD->setInvalidDecl(); 2876 } 2877 2878 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2879 2880 // This is an explicit specialization of a static data member. Check it. 2881 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2882 CheckMemberSpecialization(NewVD, Previous)) 2883 NewVD->setInvalidDecl(); 2884 2885 // attributes declared post-definition are currently ignored 2886 // FIXME: This should be handled in attribute merging, not 2887 // here. 2888 if (Previous.isSingleResult()) { 2889 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2890 if (Def && (Def = Def->getDefinition()) && 2891 Def != NewVD && D.hasAttributes()) { 2892 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2893 Diag(Def->getLocation(), diag::note_previous_definition); 2894 } 2895 } 2896 2897 // If this is a locally-scoped extern C variable, update the map of 2898 // such variables. 2899 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2900 !NewVD->isInvalidDecl()) 2901 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2902 2903 // If there's a #pragma GCC visibility in scope, and this isn't a class 2904 // member, set the visibility of this variable. 2905 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2906 AddPushedVisibilityAttribute(NewVD); 2907 2908 MarkUnusedFileScopedDecl(NewVD); 2909 2910 return NewVD; 2911} 2912 2913/// \brief Diagnose variable or built-in function shadowing. Implements 2914/// -Wshadow. 2915/// 2916/// This method is called whenever a VarDecl is added to a "useful" 2917/// scope. 2918/// 2919/// \param S the scope in which the shadowing name is being declared 2920/// \param R the lookup of the name 2921/// 2922void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2923 // Return if warning is ignored. 2924 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2925 return; 2926 2927 // Don't diagnose declarations at file scope. The scope might not 2928 // have a DeclContext if (e.g.) we're parsing a function prototype. 2929 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2930 if (NewDC && NewDC->isFileContext()) 2931 return; 2932 2933 // Only diagnose if we're shadowing an unambiguous field or variable. 2934 if (R.getResultKind() != LookupResult::Found) 2935 return; 2936 2937 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2938 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2939 return; 2940 2941 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2942 2943 // Only warn about certain kinds of shadowing for class members. 2944 if (NewDC && NewDC->isRecord()) { 2945 // In particular, don't warn about shadowing non-class members. 2946 if (!OldDC->isRecord()) 2947 return; 2948 2949 // TODO: should we warn about static data members shadowing 2950 // static data members from base classes? 2951 2952 // TODO: don't diagnose for inaccessible shadowed members. 2953 // This is hard to do perfectly because we might friend the 2954 // shadowing context, but that's just a false negative. 2955 } 2956 2957 // Determine what kind of declaration we're shadowing. 2958 unsigned Kind; 2959 if (isa<RecordDecl>(OldDC)) { 2960 if (isa<FieldDecl>(ShadowedDecl)) 2961 Kind = 3; // field 2962 else 2963 Kind = 2; // static data member 2964 } else if (OldDC->isFileContext()) 2965 Kind = 1; // global 2966 else 2967 Kind = 0; // local 2968 2969 DeclarationName Name = R.getLookupName(); 2970 2971 // Emit warning and note. 2972 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2973 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2974} 2975 2976/// \brief Check -Wshadow without the advantage of a previous lookup. 2977void Sema::CheckShadow(Scope *S, VarDecl *D) { 2978 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2979 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2980 LookupName(R, S); 2981 CheckShadow(S, D, R); 2982} 2983 2984/// \brief Perform semantic checking on a newly-created variable 2985/// declaration. 2986/// 2987/// This routine performs all of the type-checking required for a 2988/// variable declaration once it has been built. It is used both to 2989/// check variables after they have been parsed and their declarators 2990/// have been translated into a declaration, and to check variables 2991/// that have been instantiated from a template. 2992/// 2993/// Sets NewVD->isInvalidDecl() if an error was encountered. 2994void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2995 LookupResult &Previous, 2996 bool &Redeclaration) { 2997 // If the decl is already known invalid, don't check it. 2998 if (NewVD->isInvalidDecl()) 2999 return; 3000 3001 QualType T = NewVD->getType(); 3002 3003 if (T->isObjCObjectType()) { 3004 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3005 return NewVD->setInvalidDecl(); 3006 } 3007 3008 // Emit an error if an address space was applied to decl with local storage. 3009 // This includes arrays of objects with address space qualifiers, but not 3010 // automatic variables that point to other address spaces. 3011 // ISO/IEC TR 18037 S5.1.2 3012 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3013 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3014 return NewVD->setInvalidDecl(); 3015 } 3016 3017 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3018 && !NewVD->hasAttr<BlocksAttr>()) 3019 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3020 3021 bool isVM = T->isVariablyModifiedType(); 3022 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3023 NewVD->hasAttr<BlocksAttr>()) 3024 getCurFunction()->setHasBranchProtectedScope(); 3025 3026 if ((isVM && NewVD->hasLinkage()) || 3027 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3028 bool SizeIsNegative; 3029 llvm::APSInt Oversized; 3030 QualType FixedTy = 3031 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3032 Oversized); 3033 3034 if (FixedTy.isNull() && T->isVariableArrayType()) { 3035 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3036 // FIXME: This won't give the correct result for 3037 // int a[10][n]; 3038 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3039 3040 if (NewVD->isFileVarDecl()) 3041 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3042 << SizeRange; 3043 else if (NewVD->getStorageClass() == SC_Static) 3044 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3045 << SizeRange; 3046 else 3047 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3048 << SizeRange; 3049 return NewVD->setInvalidDecl(); 3050 } 3051 3052 if (FixedTy.isNull()) { 3053 if (NewVD->isFileVarDecl()) 3054 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3055 else 3056 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3057 return NewVD->setInvalidDecl(); 3058 } 3059 3060 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3061 NewVD->setType(FixedTy); 3062 } 3063 3064 if (Previous.empty() && NewVD->isExternC()) { 3065 // Since we did not find anything by this name and we're declaring 3066 // an extern "C" variable, look for a non-visible extern "C" 3067 // declaration with the same name. 3068 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3069 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3070 if (Pos != LocallyScopedExternalDecls.end()) 3071 Previous.addDecl(Pos->second); 3072 } 3073 3074 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3075 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3076 << T; 3077 return NewVD->setInvalidDecl(); 3078 } 3079 3080 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3081 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3082 return NewVD->setInvalidDecl(); 3083 } 3084 3085 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3086 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3087 return NewVD->setInvalidDecl(); 3088 } 3089 3090 // Function pointers and references cannot have qualified function type, only 3091 // function pointer-to-members can do that. 3092 QualType Pointee; 3093 unsigned PtrOrRef = 0; 3094 if (const PointerType *Ptr = T->getAs<PointerType>()) 3095 Pointee = Ptr->getPointeeType(); 3096 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3097 Pointee = Ref->getPointeeType(); 3098 PtrOrRef = 1; 3099 } 3100 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3101 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3102 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3103 << PtrOrRef; 3104 return NewVD->setInvalidDecl(); 3105 } 3106 3107 if (!Previous.empty()) { 3108 Redeclaration = true; 3109 MergeVarDecl(NewVD, Previous); 3110 } 3111} 3112 3113/// \brief Data used with FindOverriddenMethod 3114struct FindOverriddenMethodData { 3115 Sema *S; 3116 CXXMethodDecl *Method; 3117}; 3118 3119/// \brief Member lookup function that determines whether a given C++ 3120/// method overrides a method in a base class, to be used with 3121/// CXXRecordDecl::lookupInBases(). 3122static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3123 CXXBasePath &Path, 3124 void *UserData) { 3125 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3126 3127 FindOverriddenMethodData *Data 3128 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3129 3130 DeclarationName Name = Data->Method->getDeclName(); 3131 3132 // FIXME: Do we care about other names here too? 3133 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3134 // We really want to find the base class destructor here. 3135 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3136 CanQualType CT = Data->S->Context.getCanonicalType(T); 3137 3138 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3139 } 3140 3141 for (Path.Decls = BaseRecord->lookup(Name); 3142 Path.Decls.first != Path.Decls.second; 3143 ++Path.Decls.first) { 3144 NamedDecl *D = *Path.Decls.first; 3145 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3146 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3147 return true; 3148 } 3149 } 3150 3151 return false; 3152} 3153 3154/// AddOverriddenMethods - See if a method overrides any in the base classes, 3155/// and if so, check that it's a valid override and remember it. 3156bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3157 // Look for virtual methods in base classes that this method might override. 3158 CXXBasePaths Paths; 3159 FindOverriddenMethodData Data; 3160 Data.Method = MD; 3161 Data.S = this; 3162 bool AddedAny = false; 3163 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3164 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3165 E = Paths.found_decls_end(); I != E; ++I) { 3166 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3167 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3168 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3169 !CheckOverridingFunctionAttributes(MD, OldMD)) { 3170 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3171 AddedAny = true; 3172 } 3173 } 3174 } 3175 } 3176 3177 return AddedAny; 3178} 3179 3180static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3181 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3182 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3183 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3184 assert(!Prev.isAmbiguous() && 3185 "Cannot have an ambiguity in previous-declaration lookup"); 3186 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3187 Func != FuncEnd; ++Func) { 3188 if (isa<FunctionDecl>(*Func) && 3189 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3190 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3191 } 3192} 3193 3194NamedDecl* 3195Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3196 QualType R, TypeSourceInfo *TInfo, 3197 LookupResult &Previous, 3198 MultiTemplateParamsArg TemplateParamLists, 3199 bool IsFunctionDefinition, bool &Redeclaration) { 3200 assert(R.getTypePtr()->isFunctionType()); 3201 3202 // TODO: consider using NameInfo for diagnostic. 3203 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3204 DeclarationName Name = NameInfo.getName(); 3205 FunctionDecl::StorageClass SC = SC_None; 3206 switch (D.getDeclSpec().getStorageClassSpec()) { 3207 default: assert(0 && "Unknown storage class!"); 3208 case DeclSpec::SCS_auto: 3209 case DeclSpec::SCS_register: 3210 case DeclSpec::SCS_mutable: 3211 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3212 diag::err_typecheck_sclass_func); 3213 D.setInvalidType(); 3214 break; 3215 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3216 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3217 case DeclSpec::SCS_static: { 3218 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3219 // C99 6.7.1p5: 3220 // The declaration of an identifier for a function that has 3221 // block scope shall have no explicit storage-class specifier 3222 // other than extern 3223 // See also (C++ [dcl.stc]p4). 3224 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3225 diag::err_static_block_func); 3226 SC = SC_None; 3227 } else 3228 SC = SC_Static; 3229 break; 3230 } 3231 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3232 } 3233 3234 if (D.getDeclSpec().isThreadSpecified()) 3235 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3236 3237 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3238 bool isInline = D.getDeclSpec().isInlineSpecified(); 3239 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3240 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3241 3242 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3243 FunctionDecl::StorageClass SCAsWritten 3244 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3245 3246 // Check that the return type is not an abstract class type. 3247 // For record types, this is done by the AbstractClassUsageDiagnoser once 3248 // the class has been completely parsed. 3249 if (!DC->isRecord() && 3250 RequireNonAbstractType(D.getIdentifierLoc(), 3251 R->getAs<FunctionType>()->getResultType(), 3252 diag::err_abstract_type_in_decl, 3253 AbstractReturnType)) 3254 D.setInvalidType(); 3255 3256 // Do not allow returning a objc interface by-value. 3257 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3258 Diag(D.getIdentifierLoc(), 3259 diag::err_object_cannot_be_passed_returned_by_value) << 0 3260 << R->getAs<FunctionType>()->getResultType(); 3261 D.setInvalidType(); 3262 } 3263 3264 bool isVirtualOkay = false; 3265 FunctionDecl *NewFD; 3266 3267 if (isFriend) { 3268 // C++ [class.friend]p5 3269 // A function can be defined in a friend declaration of a 3270 // class . . . . Such a function is implicitly inline. 3271 isInline |= IsFunctionDefinition; 3272 } 3273 3274 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3275 // This is a C++ constructor declaration. 3276 assert(DC->isRecord() && 3277 "Constructors can only be declared in a member context"); 3278 3279 R = CheckConstructorDeclarator(D, R, SC); 3280 3281 // Create the new declaration 3282 NewFD = CXXConstructorDecl::Create(Context, 3283 cast<CXXRecordDecl>(DC), 3284 NameInfo, R, TInfo, 3285 isExplicit, isInline, 3286 /*isImplicitlyDeclared=*/false); 3287 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3288 // This is a C++ destructor declaration. 3289 if (DC->isRecord()) { 3290 R = CheckDestructorDeclarator(D, R, SC); 3291 3292 NewFD = CXXDestructorDecl::Create(Context, 3293 cast<CXXRecordDecl>(DC), 3294 NameInfo, R, 3295 isInline, 3296 /*isImplicitlyDeclared=*/false); 3297 NewFD->setTypeSourceInfo(TInfo); 3298 3299 isVirtualOkay = true; 3300 } else { 3301 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3302 3303 // Create a FunctionDecl to satisfy the function definition parsing 3304 // code path. 3305 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3306 Name, R, TInfo, SC, SCAsWritten, isInline, 3307 /*hasPrototype=*/true); 3308 D.setInvalidType(); 3309 } 3310 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3311 if (!DC->isRecord()) { 3312 Diag(D.getIdentifierLoc(), 3313 diag::err_conv_function_not_member); 3314 return 0; 3315 } 3316 3317 CheckConversionDeclarator(D, R, SC); 3318 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3319 NameInfo, R, TInfo, 3320 isInline, isExplicit); 3321 3322 isVirtualOkay = true; 3323 } else if (DC->isRecord()) { 3324 // If the of the function is the same as the name of the record, then this 3325 // must be an invalid constructor that has a return type. 3326 // (The parser checks for a return type and makes the declarator a 3327 // constructor if it has no return type). 3328 // must have an invalid constructor that has a return type 3329 if (Name.getAsIdentifierInfo() && 3330 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3331 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3332 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3333 << SourceRange(D.getIdentifierLoc()); 3334 return 0; 3335 } 3336 3337 bool isStatic = SC == SC_Static; 3338 3339 // [class.free]p1: 3340 // Any allocation function for a class T is a static member 3341 // (even if not explicitly declared static). 3342 if (Name.getCXXOverloadedOperator() == OO_New || 3343 Name.getCXXOverloadedOperator() == OO_Array_New) 3344 isStatic = true; 3345 3346 // [class.free]p6 Any deallocation function for a class X is a static member 3347 // (even if not explicitly declared static). 3348 if (Name.getCXXOverloadedOperator() == OO_Delete || 3349 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3350 isStatic = true; 3351 3352 // This is a C++ method declaration. 3353 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3354 NameInfo, R, TInfo, 3355 isStatic, SCAsWritten, isInline); 3356 3357 isVirtualOkay = !isStatic; 3358 } else { 3359 // Determine whether the function was written with a 3360 // prototype. This true when: 3361 // - we're in C++ (where every function has a prototype), 3362 // - there is a prototype in the declarator, or 3363 // - the type R of the function is some kind of typedef or other reference 3364 // to a type name (which eventually refers to a function type). 3365 bool HasPrototype = 3366 getLangOptions().CPlusPlus || 3367 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3368 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3369 3370 NewFD = FunctionDecl::Create(Context, DC, 3371 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3372 HasPrototype); 3373 } 3374 3375 if (D.isInvalidType()) 3376 NewFD->setInvalidDecl(); 3377 3378 SetNestedNameSpecifier(NewFD, D); 3379 3380 // Set the lexical context. If the declarator has a C++ 3381 // scope specifier, or is the object of a friend declaration, the 3382 // lexical context will be different from the semantic context. 3383 NewFD->setLexicalDeclContext(CurContext); 3384 3385 // Match up the template parameter lists with the scope specifier, then 3386 // determine whether we have a template or a template specialization. 3387 FunctionTemplateDecl *FunctionTemplate = 0; 3388 bool isExplicitSpecialization = false; 3389 bool isFunctionTemplateSpecialization = false; 3390 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3391 bool Invalid = false; 3392 if (TemplateParameterList *TemplateParams 3393 = MatchTemplateParametersToScopeSpecifier( 3394 D.getDeclSpec().getSourceRange().getBegin(), 3395 D.getCXXScopeSpec(), 3396 (TemplateParameterList**)TemplateParamLists.get(), 3397 TemplateParamLists.size(), 3398 isFriend, 3399 isExplicitSpecialization, 3400 Invalid)) { 3401 // All but one template parameter lists have been matching. 3402 --NumMatchedTemplateParamLists; 3403 3404 if (TemplateParams->size() > 0) { 3405 // This is a function template 3406 3407 // Check that we can declare a template here. 3408 if (CheckTemplateDeclScope(S, TemplateParams)) 3409 return 0; 3410 3411 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3412 NewFD->getLocation(), 3413 Name, TemplateParams, 3414 NewFD); 3415 FunctionTemplate->setLexicalDeclContext(CurContext); 3416 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3417 } else { 3418 // This is a function template specialization. 3419 isFunctionTemplateSpecialization = true; 3420 3421 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3422 if (isFriend && isFunctionTemplateSpecialization) { 3423 // We want to remove the "template<>", found here. 3424 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3425 3426 // If we remove the template<> and the name is not a 3427 // template-id, we're actually silently creating a problem: 3428 // the friend declaration will refer to an untemplated decl, 3429 // and clearly the user wants a template specialization. So 3430 // we need to insert '<>' after the name. 3431 SourceLocation InsertLoc; 3432 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3433 InsertLoc = D.getName().getSourceRange().getEnd(); 3434 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3435 } 3436 3437 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3438 << Name << RemoveRange 3439 << FixItHint::CreateRemoval(RemoveRange) 3440 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3441 } 3442 } 3443 } 3444 3445 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3446 NewFD->setTemplateParameterListsInfo(Context, 3447 NumMatchedTemplateParamLists, 3448 (TemplateParameterList**)TemplateParamLists.release()); 3449 } 3450 3451 if (Invalid) { 3452 NewFD->setInvalidDecl(); 3453 if (FunctionTemplate) 3454 FunctionTemplate->setInvalidDecl(); 3455 } 3456 3457 // C++ [dcl.fct.spec]p5: 3458 // The virtual specifier shall only be used in declarations of 3459 // nonstatic class member functions that appear within a 3460 // member-specification of a class declaration; see 10.3. 3461 // 3462 if (isVirtual && !NewFD->isInvalidDecl()) { 3463 if (!isVirtualOkay) { 3464 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3465 diag::err_virtual_non_function); 3466 } else if (!CurContext->isRecord()) { 3467 // 'virtual' was specified outside of the class. 3468 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3469 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3470 } else { 3471 // Okay: Add virtual to the method. 3472 NewFD->setVirtualAsWritten(true); 3473 } 3474 } 3475 3476 // C++ [dcl.fct.spec]p3: 3477 // The inline specifier shall not appear on a block scope function declaration. 3478 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3479 if (CurContext->isFunctionOrMethod()) { 3480 // 'inline' is not allowed on block scope function declaration. 3481 Diag(D.getDeclSpec().getInlineSpecLoc(), 3482 diag::err_inline_declaration_block_scope) << Name 3483 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3484 } 3485 } 3486 3487 // C++ [dcl.fct.spec]p6: 3488 // The explicit specifier shall be used only in the declaration of a 3489 // constructor or conversion function within its class definition; see 12.3.1 3490 // and 12.3.2. 3491 if (isExplicit && !NewFD->isInvalidDecl()) { 3492 if (!CurContext->isRecord()) { 3493 // 'explicit' was specified outside of the class. 3494 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3495 diag::err_explicit_out_of_class) 3496 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3497 } else if (!isa<CXXConstructorDecl>(NewFD) && 3498 !isa<CXXConversionDecl>(NewFD)) { 3499 // 'explicit' was specified on a function that wasn't a constructor 3500 // or conversion function. 3501 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3502 diag::err_explicit_non_ctor_or_conv_function) 3503 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3504 } 3505 } 3506 3507 // Filter out previous declarations that don't match the scope. 3508 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3509 3510 if (isFriend) { 3511 // For now, claim that the objects have no previous declaration. 3512 if (FunctionTemplate) { 3513 FunctionTemplate->setObjectOfFriendDecl(false); 3514 FunctionTemplate->setAccess(AS_public); 3515 } 3516 NewFD->setObjectOfFriendDecl(false); 3517 NewFD->setAccess(AS_public); 3518 } 3519 3520 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3521 !CurContext->isRecord()) { 3522 // C++ [class.static]p1: 3523 // A data or function member of a class may be declared static 3524 // in a class definition, in which case it is a static member of 3525 // the class. 3526 3527 // Complain about the 'static' specifier if it's on an out-of-line 3528 // member function definition. 3529 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3530 diag::err_static_out_of_line) 3531 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3532 } 3533 3534 // Handle GNU asm-label extension (encoded as an attribute). 3535 if (Expr *E = (Expr*) D.getAsmLabel()) { 3536 // The parser guarantees this is a string. 3537 StringLiteral *SE = cast<StringLiteral>(E); 3538 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3539 SE->getString())); 3540 } 3541 3542 // Copy the parameter declarations from the declarator D to the function 3543 // declaration NewFD, if they are available. First scavenge them into Params. 3544 llvm::SmallVector<ParmVarDecl*, 16> Params; 3545 if (D.getNumTypeObjects() > 0) { 3546 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3547 3548 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3549 // function that takes no arguments, not a function that takes a 3550 // single void argument. 3551 // We let through "const void" here because Sema::GetTypeForDeclarator 3552 // already checks for that case. 3553 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3554 FTI.ArgInfo[0].Param && 3555 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3556 // Empty arg list, don't push any params. 3557 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3558 3559 // In C++, the empty parameter-type-list must be spelled "void"; a 3560 // typedef of void is not permitted. 3561 if (getLangOptions().CPlusPlus && 3562 Param->getType().getUnqualifiedType() != Context.VoidTy) 3563 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3564 // FIXME: Leaks decl? 3565 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3566 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3567 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3568 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3569 Param->setDeclContext(NewFD); 3570 Params.push_back(Param); 3571 3572 if (Param->isInvalidDecl()) 3573 NewFD->setInvalidDecl(); 3574 } 3575 } 3576 3577 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3578 // When we're declaring a function with a typedef, typeof, etc as in the 3579 // following example, we'll need to synthesize (unnamed) 3580 // parameters for use in the declaration. 3581 // 3582 // @code 3583 // typedef void fn(int); 3584 // fn f; 3585 // @endcode 3586 3587 // Synthesize a parameter for each argument type. 3588 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3589 AE = FT->arg_type_end(); AI != AE; ++AI) { 3590 ParmVarDecl *Param = 3591 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3592 Params.push_back(Param); 3593 } 3594 } else { 3595 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3596 "Should not need args for typedef of non-prototype fn"); 3597 } 3598 // Finally, we know we have the right number of parameters, install them. 3599 NewFD->setParams(Params.data(), Params.size()); 3600 3601 // If the declarator is a template-id, translate the parser's template 3602 // argument list into our AST format. 3603 bool HasExplicitTemplateArgs = false; 3604 TemplateArgumentListInfo TemplateArgs; 3605 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3606 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3607 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3608 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3609 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3610 TemplateId->getTemplateArgs(), 3611 TemplateId->NumArgs); 3612 translateTemplateArguments(TemplateArgsPtr, 3613 TemplateArgs); 3614 TemplateArgsPtr.release(); 3615 3616 HasExplicitTemplateArgs = true; 3617 3618 if (FunctionTemplate) { 3619 // FIXME: Diagnose function template with explicit template 3620 // arguments. 3621 HasExplicitTemplateArgs = false; 3622 } else if (!isFunctionTemplateSpecialization && 3623 !D.getDeclSpec().isFriendSpecified()) { 3624 // We have encountered something that the user meant to be a 3625 // specialization (because it has explicitly-specified template 3626 // arguments) but that was not introduced with a "template<>" (or had 3627 // too few of them). 3628 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3629 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3630 << FixItHint::CreateInsertion( 3631 D.getDeclSpec().getSourceRange().getBegin(), 3632 "template<> "); 3633 isFunctionTemplateSpecialization = true; 3634 } else { 3635 // "friend void foo<>(int);" is an implicit specialization decl. 3636 isFunctionTemplateSpecialization = true; 3637 } 3638 } else if (isFriend && isFunctionTemplateSpecialization) { 3639 // This combination is only possible in a recovery case; the user 3640 // wrote something like: 3641 // template <> friend void foo(int); 3642 // which we're recovering from as if the user had written: 3643 // friend void foo<>(int); 3644 // Go ahead and fake up a template id. 3645 HasExplicitTemplateArgs = true; 3646 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3647 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3648 } 3649 3650 // If it's a friend (and only if it's a friend), it's possible 3651 // that either the specialized function type or the specialized 3652 // template is dependent, and therefore matching will fail. In 3653 // this case, don't check the specialization yet. 3654 if (isFunctionTemplateSpecialization && isFriend && 3655 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3656 assert(HasExplicitTemplateArgs && 3657 "friend function specialization without template args"); 3658 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3659 Previous)) 3660 NewFD->setInvalidDecl(); 3661 } else if (isFunctionTemplateSpecialization) { 3662 if (CheckFunctionTemplateSpecialization(NewFD, 3663 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3664 Previous)) 3665 NewFD->setInvalidDecl(); 3666 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3667 if (CheckMemberSpecialization(NewFD, Previous)) 3668 NewFD->setInvalidDecl(); 3669 } 3670 3671 // Perform semantic checking on the function declaration. 3672 bool OverloadableAttrRequired = false; // FIXME: HACK! 3673 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3674 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3675 3676 assert((NewFD->isInvalidDecl() || !Redeclaration || 3677 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3678 "previous declaration set still overloaded"); 3679 3680 NamedDecl *PrincipalDecl = (FunctionTemplate 3681 ? cast<NamedDecl>(FunctionTemplate) 3682 : NewFD); 3683 3684 if (isFriend && Redeclaration) { 3685 AccessSpecifier Access = AS_public; 3686 if (!NewFD->isInvalidDecl()) 3687 Access = NewFD->getPreviousDeclaration()->getAccess(); 3688 3689 NewFD->setAccess(Access); 3690 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3691 3692 PrincipalDecl->setObjectOfFriendDecl(true); 3693 } 3694 3695 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3696 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3697 PrincipalDecl->setNonMemberOperator(); 3698 3699 // If we have a function template, check the template parameter 3700 // list. This will check and merge default template arguments. 3701 if (FunctionTemplate) { 3702 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3703 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3704 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3705 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3706 : TPC_FunctionTemplate); 3707 } 3708 3709 if (NewFD->isInvalidDecl()) { 3710 // Ignore all the rest of this. 3711 } else if (!Redeclaration) { 3712 // Fake up an access specifier if it's supposed to be a class member. 3713 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 3714 NewFD->setAccess(AS_public); 3715 3716 // Qualified decls generally require a previous declaration. 3717 if (D.getCXXScopeSpec().isSet()) { 3718 // ...with the major exception of dependent friend declarations. 3719 // In theory, this condition could be whether the qualifier 3720 // is dependent; in practice, the way we nest template parameters 3721 // prevents this sort of matching from working, so we have to base it 3722 // on the general dependence of the context. 3723 if (isFriend && CurContext->isDependentContext()) { 3724 // ignore these 3725 3726 } else { 3727 // The user tried to provide an out-of-line definition for a 3728 // function that is a member of a class or namespace, but there 3729 // was no such member function declared (C++ [class.mfct]p2, 3730 // C++ [namespace.memdef]p2). For example: 3731 // 3732 // class X { 3733 // void f() const; 3734 // }; 3735 // 3736 // void X::f() { } // ill-formed 3737 // 3738 // Complain about this problem, and attempt to suggest close 3739 // matches (e.g., those that differ only in cv-qualifiers and 3740 // whether the parameter types are references). 3741 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3742 << Name << DC << D.getCXXScopeSpec().getRange(); 3743 NewFD->setInvalidDecl(); 3744 3745 DiagnoseInvalidRedeclaration(*this, NewFD); 3746 } 3747 3748 // Unqualified local friend declarations are required to resolve 3749 // to something. 3750 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 3751 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 3752 NewFD->setInvalidDecl(); 3753 DiagnoseInvalidRedeclaration(*this, NewFD); 3754 } 3755 3756 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 3757 !isFriend && !isFunctionTemplateSpecialization && 3758 !isExplicitSpecialization) { 3759 // An out-of-line member function declaration must also be a 3760 // definition (C++ [dcl.meaning]p1). 3761 // Note that this is not the case for explicit specializations of 3762 // function templates or member functions of class templates, per 3763 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3764 // for compatibility with old SWIG code which likes to generate them. 3765 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3766 << D.getCXXScopeSpec().getRange(); 3767 } 3768 3769 // Handle attributes. We need to have merged decls when handling attributes 3770 // (for example to check for conflicts, etc). 3771 // FIXME: This needs to happen before we merge declarations. Then, 3772 // let attribute merging cope with attribute conflicts. 3773 ProcessDeclAttributes(S, NewFD, D); 3774 3775 // attributes declared post-definition are currently ignored 3776 // FIXME: This should happen during attribute merging 3777 if (Redeclaration && Previous.isSingleResult()) { 3778 const FunctionDecl *Def; 3779 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3780 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3781 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3782 Diag(Def->getLocation(), diag::note_previous_definition); 3783 } 3784 } 3785 3786 AddKnownFunctionAttributes(NewFD); 3787 3788 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3789 // If a function name is overloadable in C, then every function 3790 // with that name must be marked "overloadable". 3791 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3792 << Redeclaration << NewFD; 3793 if (!Previous.empty()) 3794 Diag(Previous.getRepresentativeDecl()->getLocation(), 3795 diag::note_attribute_overloadable_prev_overload); 3796 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3797 } 3798 3799 if (NewFD->hasAttr<OverloadableAttr>() && 3800 !NewFD->getType()->getAs<FunctionProtoType>()) { 3801 Diag(NewFD->getLocation(), 3802 diag::err_attribute_overloadable_no_prototype) 3803 << NewFD; 3804 3805 // Turn this into a variadic function with no parameters. 3806 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3807 QualType R = Context.getFunctionType(FT->getResultType(), 3808 0, 0, true, 0, false, false, 0, 0, 3809 FT->getExtInfo()); 3810 NewFD->setType(R); 3811 } 3812 3813 // If there's a #pragma GCC visibility in scope, and this isn't a class 3814 // member, set the visibility of this function. 3815 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3816 AddPushedVisibilityAttribute(NewFD); 3817 3818 // If this is a locally-scoped extern C function, update the 3819 // map of such names. 3820 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3821 && !NewFD->isInvalidDecl()) 3822 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3823 3824 // Set this FunctionDecl's range up to the right paren. 3825 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3826 3827 if (FunctionTemplate && NewFD->isInvalidDecl()) 3828 FunctionTemplate->setInvalidDecl(); 3829 3830 if (FunctionTemplate) 3831 return FunctionTemplate; 3832 3833 MarkUnusedFileScopedDecl(NewFD); 3834 3835 return NewFD; 3836} 3837 3838/// \brief Perform semantic checking of a new function declaration. 3839/// 3840/// Performs semantic analysis of the new function declaration 3841/// NewFD. This routine performs all semantic checking that does not 3842/// require the actual declarator involved in the declaration, and is 3843/// used both for the declaration of functions as they are parsed 3844/// (called via ActOnDeclarator) and for the declaration of functions 3845/// that have been instantiated via C++ template instantiation (called 3846/// via InstantiateDecl). 3847/// 3848/// \param IsExplicitSpecialiation whether this new function declaration is 3849/// an explicit specialization of the previous declaration. 3850/// 3851/// This sets NewFD->isInvalidDecl() to true if there was an error. 3852void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3853 LookupResult &Previous, 3854 bool IsExplicitSpecialization, 3855 bool &Redeclaration, 3856 bool &OverloadableAttrRequired) { 3857 // If NewFD is already known erroneous, don't do any of this checking. 3858 if (NewFD->isInvalidDecl()) { 3859 // If this is a class member, mark the class invalid immediately. 3860 // This avoids some consistency errors later. 3861 if (isa<CXXMethodDecl>(NewFD)) 3862 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3863 3864 return; 3865 } 3866 3867 if (NewFD->getResultType()->isVariablyModifiedType()) { 3868 // Functions returning a variably modified type violate C99 6.7.5.2p2 3869 // because all functions have linkage. 3870 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3871 return NewFD->setInvalidDecl(); 3872 } 3873 3874 if (NewFD->isMain()) 3875 CheckMain(NewFD); 3876 3877 // Check for a previous declaration of this name. 3878 if (Previous.empty() && NewFD->isExternC()) { 3879 // Since we did not find anything by this name and we're declaring 3880 // an extern "C" function, look for a non-visible extern "C" 3881 // declaration with the same name. 3882 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3883 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3884 if (Pos != LocallyScopedExternalDecls.end()) 3885 Previous.addDecl(Pos->second); 3886 } 3887 3888 // Merge or overload the declaration with an existing declaration of 3889 // the same name, if appropriate. 3890 if (!Previous.empty()) { 3891 // Determine whether NewFD is an overload of PrevDecl or 3892 // a declaration that requires merging. If it's an overload, 3893 // there's no more work to do here; we'll just add the new 3894 // function to the scope. 3895 3896 NamedDecl *OldDecl = 0; 3897 if (!AllowOverloadingOfFunction(Previous, Context)) { 3898 Redeclaration = true; 3899 OldDecl = Previous.getFoundDecl(); 3900 } else { 3901 if (!getLangOptions().CPlusPlus) 3902 OverloadableAttrRequired = true; 3903 3904 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3905 /*NewIsUsingDecl*/ false)) { 3906 case Ovl_Match: 3907 Redeclaration = true; 3908 break; 3909 3910 case Ovl_NonFunction: 3911 Redeclaration = true; 3912 break; 3913 3914 case Ovl_Overload: 3915 Redeclaration = false; 3916 break; 3917 } 3918 } 3919 3920 if (Redeclaration) { 3921 // NewFD and OldDecl represent declarations that need to be 3922 // merged. 3923 if (MergeFunctionDecl(NewFD, OldDecl)) 3924 return NewFD->setInvalidDecl(); 3925 3926 Previous.clear(); 3927 Previous.addDecl(OldDecl); 3928 3929 if (FunctionTemplateDecl *OldTemplateDecl 3930 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3931 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3932 FunctionTemplateDecl *NewTemplateDecl 3933 = NewFD->getDescribedFunctionTemplate(); 3934 assert(NewTemplateDecl && "Template/non-template mismatch"); 3935 if (CXXMethodDecl *Method 3936 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3937 Method->setAccess(OldTemplateDecl->getAccess()); 3938 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3939 } 3940 3941 // If this is an explicit specialization of a member that is a function 3942 // template, mark it as a member specialization. 3943 if (IsExplicitSpecialization && 3944 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3945 NewTemplateDecl->setMemberSpecialization(); 3946 assert(OldTemplateDecl->isMemberSpecialization()); 3947 } 3948 } else { 3949 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3950 NewFD->setAccess(OldDecl->getAccess()); 3951 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3952 } 3953 } 3954 } 3955 3956 // Semantic checking for this function declaration (in isolation). 3957 if (getLangOptions().CPlusPlus) { 3958 // C++-specific checks. 3959 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3960 CheckConstructor(Constructor); 3961 } else if (CXXDestructorDecl *Destructor = 3962 dyn_cast<CXXDestructorDecl>(NewFD)) { 3963 CXXRecordDecl *Record = Destructor->getParent(); 3964 QualType ClassType = Context.getTypeDeclType(Record); 3965 3966 // FIXME: Shouldn't we be able to perform this check even when the class 3967 // type is dependent? Both gcc and edg can handle that. 3968 if (!ClassType->isDependentType()) { 3969 DeclarationName Name 3970 = Context.DeclarationNames.getCXXDestructorName( 3971 Context.getCanonicalType(ClassType)); 3972 if (NewFD->getDeclName() != Name) { 3973 Diag(NewFD->getLocation(), diag::err_destructor_name); 3974 return NewFD->setInvalidDecl(); 3975 } 3976 } 3977 } else if (CXXConversionDecl *Conversion 3978 = dyn_cast<CXXConversionDecl>(NewFD)) { 3979 ActOnConversionDeclarator(Conversion); 3980 } 3981 3982 // Find any virtual functions that this function overrides. 3983 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3984 if (!Method->isFunctionTemplateSpecialization() && 3985 !Method->getDescribedFunctionTemplate()) { 3986 if (AddOverriddenMethods(Method->getParent(), Method)) { 3987 // If the function was marked as "static", we have a problem. 3988 if (NewFD->getStorageClass() == SC_Static) { 3989 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 3990 << NewFD->getDeclName(); 3991 for (CXXMethodDecl::method_iterator 3992 Overridden = Method->begin_overridden_methods(), 3993 OverriddenEnd = Method->end_overridden_methods(); 3994 Overridden != OverriddenEnd; 3995 ++Overridden) { 3996 Diag((*Overridden)->getLocation(), 3997 diag::note_overridden_virtual_function); 3998 } 3999 } 4000 } 4001 } 4002 } 4003 4004 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4005 if (NewFD->isOverloadedOperator() && 4006 CheckOverloadedOperatorDeclaration(NewFD)) 4007 return NewFD->setInvalidDecl(); 4008 4009 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4010 if (NewFD->getLiteralIdentifier() && 4011 CheckLiteralOperatorDeclaration(NewFD)) 4012 return NewFD->setInvalidDecl(); 4013 4014 // In C++, check default arguments now that we have merged decls. Unless 4015 // the lexical context is the class, because in this case this is done 4016 // during delayed parsing anyway. 4017 if (!CurContext->isRecord()) 4018 CheckCXXDefaultArguments(NewFD); 4019 } 4020} 4021 4022void Sema::CheckMain(FunctionDecl* FD) { 4023 // C++ [basic.start.main]p3: A program that declares main to be inline 4024 // or static is ill-formed. 4025 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4026 // shall not appear in a declaration of main. 4027 // static main is not an error under C99, but we should warn about it. 4028 bool isInline = FD->isInlineSpecified(); 4029 bool isStatic = FD->getStorageClass() == SC_Static; 4030 if (isInline || isStatic) { 4031 unsigned diagID = diag::warn_unusual_main_decl; 4032 if (isInline || getLangOptions().CPlusPlus) 4033 diagID = diag::err_unusual_main_decl; 4034 4035 int which = isStatic + (isInline << 1) - 1; 4036 Diag(FD->getLocation(), diagID) << which; 4037 } 4038 4039 QualType T = FD->getType(); 4040 assert(T->isFunctionType() && "function decl is not of function type"); 4041 const FunctionType* FT = T->getAs<FunctionType>(); 4042 4043 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4044 TypeSourceInfo *TSI = FD->getTypeSourceInfo(); 4045 TypeLoc TL = TSI->getTypeLoc(); 4046 const SemaDiagnosticBuilder& D = Diag(FD->getTypeSpecStartLoc(), 4047 diag::err_main_returns_nonint); 4048 if (FunctionTypeLoc* PTL = dyn_cast<FunctionTypeLoc>(&TL)) { 4049 D << FixItHint::CreateReplacement(PTL->getResultLoc().getSourceRange(), 4050 "int"); 4051 } 4052 FD->setInvalidDecl(true); 4053 } 4054 4055 // Treat protoless main() as nullary. 4056 if (isa<FunctionNoProtoType>(FT)) return; 4057 4058 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4059 unsigned nparams = FTP->getNumArgs(); 4060 assert(FD->getNumParams() == nparams); 4061 4062 bool HasExtraParameters = (nparams > 3); 4063 4064 // Darwin passes an undocumented fourth argument of type char**. If 4065 // other platforms start sprouting these, the logic below will start 4066 // getting shifty. 4067 if (nparams == 4 && 4068 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4069 HasExtraParameters = false; 4070 4071 if (HasExtraParameters) { 4072 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4073 FD->setInvalidDecl(true); 4074 nparams = 3; 4075 } 4076 4077 // FIXME: a lot of the following diagnostics would be improved 4078 // if we had some location information about types. 4079 4080 QualType CharPP = 4081 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4082 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4083 4084 for (unsigned i = 0; i < nparams; ++i) { 4085 QualType AT = FTP->getArgType(i); 4086 4087 bool mismatch = true; 4088 4089 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4090 mismatch = false; 4091 else if (Expected[i] == CharPP) { 4092 // As an extension, the following forms are okay: 4093 // char const ** 4094 // char const * const * 4095 // char * const * 4096 4097 QualifierCollector qs; 4098 const PointerType* PT; 4099 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4100 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4101 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4102 qs.removeConst(); 4103 mismatch = !qs.empty(); 4104 } 4105 } 4106 4107 if (mismatch) { 4108 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4109 // TODO: suggest replacing given type with expected type 4110 FD->setInvalidDecl(true); 4111 } 4112 } 4113 4114 if (nparams == 1 && !FD->isInvalidDecl()) { 4115 Diag(FD->getLocation(), diag::warn_main_one_arg); 4116 } 4117} 4118 4119bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4120 // FIXME: Need strict checking. In C89, we need to check for 4121 // any assignment, increment, decrement, function-calls, or 4122 // commas outside of a sizeof. In C99, it's the same list, 4123 // except that the aforementioned are allowed in unevaluated 4124 // expressions. Everything else falls under the 4125 // "may accept other forms of constant expressions" exception. 4126 // (We never end up here for C++, so the constant expression 4127 // rules there don't matter.) 4128 if (Init->isConstantInitializer(Context, false)) 4129 return false; 4130 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4131 << Init->getSourceRange(); 4132 return true; 4133} 4134 4135void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4136 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4137} 4138 4139/// AddInitializerToDecl - Adds the initializer Init to the 4140/// declaration dcl. If DirectInit is true, this is C++ direct 4141/// initialization rather than copy initialization. 4142void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4143 // If there is no declaration, there was an error parsing it. Just ignore 4144 // the initializer. 4145 if (RealDecl == 0) 4146 return; 4147 4148 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4149 // With declarators parsed the way they are, the parser cannot 4150 // distinguish between a normal initializer and a pure-specifier. 4151 // Thus this grotesque test. 4152 IntegerLiteral *IL; 4153 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4154 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4155 CheckPureMethod(Method, Init->getSourceRange()); 4156 else { 4157 Diag(Method->getLocation(), diag::err_member_function_initialization) 4158 << Method->getDeclName() << Init->getSourceRange(); 4159 Method->setInvalidDecl(); 4160 } 4161 return; 4162 } 4163 4164 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4165 if (!VDecl) { 4166 if (getLangOptions().CPlusPlus && 4167 RealDecl->getLexicalDeclContext()->isRecord() && 4168 isa<NamedDecl>(RealDecl)) 4169 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4170 else 4171 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4172 RealDecl->setInvalidDecl(); 4173 return; 4174 } 4175 4176 4177 4178 // A definition must end up with a complete type, which means it must be 4179 // complete with the restriction that an array type might be completed by the 4180 // initializer; note that later code assumes this restriction. 4181 QualType BaseDeclType = VDecl->getType(); 4182 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4183 BaseDeclType = Array->getElementType(); 4184 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4185 diag::err_typecheck_decl_incomplete_type)) { 4186 RealDecl->setInvalidDecl(); 4187 return; 4188 } 4189 4190 // The variable can not have an abstract class type. 4191 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4192 diag::err_abstract_type_in_decl, 4193 AbstractVariableType)) 4194 VDecl->setInvalidDecl(); 4195 4196 const VarDecl *Def; 4197 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4198 Diag(VDecl->getLocation(), diag::err_redefinition) 4199 << VDecl->getDeclName(); 4200 Diag(Def->getLocation(), diag::note_previous_definition); 4201 VDecl->setInvalidDecl(); 4202 return; 4203 } 4204 4205 // C++ [class.static.data]p4 4206 // If a static data member is of const integral or const 4207 // enumeration type, its declaration in the class definition can 4208 // specify a constant-initializer which shall be an integral 4209 // constant expression (5.19). In that case, the member can appear 4210 // in integral constant expressions. The member shall still be 4211 // defined in a namespace scope if it is used in the program and the 4212 // namespace scope definition shall not contain an initializer. 4213 // 4214 // We already performed a redefinition check above, but for static 4215 // data members we also need to check whether there was an in-class 4216 // declaration with an initializer. 4217 const VarDecl* PrevInit = 0; 4218 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4219 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4220 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4221 return; 4222 } 4223 4224 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4225 getCurFunction()->setHasBranchProtectedScope(); 4226 4227 // Capture the variable that is being initialized and the style of 4228 // initialization. 4229 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4230 4231 // FIXME: Poor source location information. 4232 InitializationKind Kind 4233 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4234 Init->getLocStart(), 4235 Init->getLocEnd()) 4236 : InitializationKind::CreateCopy(VDecl->getLocation(), 4237 Init->getLocStart()); 4238 4239 // Get the decls type and save a reference for later, since 4240 // CheckInitializerTypes may change it. 4241 QualType DclT = VDecl->getType(), SavT = DclT; 4242 if (VDecl->isLocalVarDecl()) { 4243 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4244 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4245 VDecl->setInvalidDecl(); 4246 } else if (!VDecl->isInvalidDecl()) { 4247 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4248 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4249 MultiExprArg(*this, &Init, 1), 4250 &DclT); 4251 if (Result.isInvalid()) { 4252 VDecl->setInvalidDecl(); 4253 return; 4254 } 4255 4256 Init = Result.takeAs<Expr>(); 4257 4258 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4259 // Don't check invalid declarations to avoid emitting useless diagnostics. 4260 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4261 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4262 CheckForConstantInitializer(Init, DclT); 4263 } 4264 } 4265 } else if (VDecl->isStaticDataMember() && 4266 VDecl->getLexicalDeclContext()->isRecord()) { 4267 // This is an in-class initialization for a static data member, e.g., 4268 // 4269 // struct S { 4270 // static const int value = 17; 4271 // }; 4272 4273 // Try to perform the initialization regardless. 4274 if (!VDecl->isInvalidDecl()) { 4275 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4276 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4277 MultiExprArg(*this, &Init, 1), 4278 &DclT); 4279 if (Result.isInvalid()) { 4280 VDecl->setInvalidDecl(); 4281 return; 4282 } 4283 4284 Init = Result.takeAs<Expr>(); 4285 } 4286 4287 // C++ [class.mem]p4: 4288 // A member-declarator can contain a constant-initializer only 4289 // if it declares a static member (9.4) of const integral or 4290 // const enumeration type, see 9.4.2. 4291 QualType T = VDecl->getType(); 4292 4293 // Do nothing on dependent types. 4294 if (T->isDependentType()) { 4295 4296 // Require constness. 4297 } else if (!T.isConstQualified()) { 4298 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4299 << Init->getSourceRange(); 4300 VDecl->setInvalidDecl(); 4301 4302 // We allow integer constant expressions in all cases. 4303 } else if (T->isIntegralOrEnumerationType()) { 4304 if (!Init->isValueDependent()) { 4305 // Check whether the expression is a constant expression. 4306 llvm::APSInt Value; 4307 SourceLocation Loc; 4308 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4309 Diag(Loc, diag::err_in_class_initializer_non_constant) 4310 << Init->getSourceRange(); 4311 VDecl->setInvalidDecl(); 4312 } 4313 } 4314 4315 // We allow floating-point constants as an extension in C++03, and 4316 // C++0x has far more complicated rules that we don't really 4317 // implement fully. 4318 } else { 4319 bool Allowed = false; 4320 if (getLangOptions().CPlusPlus0x) { 4321 Allowed = T->isLiteralType(); 4322 } else if (T->isFloatingType()) { // also permits complex, which is ok 4323 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4324 << T << Init->getSourceRange(); 4325 Allowed = true; 4326 } 4327 4328 if (!Allowed) { 4329 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4330 << T << Init->getSourceRange(); 4331 VDecl->setInvalidDecl(); 4332 4333 // TODO: there are probably expressions that pass here that shouldn't. 4334 } else if (!Init->isValueDependent() && 4335 !Init->isConstantInitializer(Context, false)) { 4336 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4337 << Init->getSourceRange(); 4338 VDecl->setInvalidDecl(); 4339 } 4340 } 4341 } else if (VDecl->isFileVarDecl()) { 4342 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4343 (!getLangOptions().CPlusPlus || 4344 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4345 Diag(VDecl->getLocation(), diag::warn_extern_init); 4346 if (!VDecl->isInvalidDecl()) { 4347 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4348 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4349 MultiExprArg(*this, &Init, 1), 4350 &DclT); 4351 if (Result.isInvalid()) { 4352 VDecl->setInvalidDecl(); 4353 return; 4354 } 4355 4356 Init = Result.takeAs<Expr>(); 4357 } 4358 4359 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4360 // Don't check invalid declarations to avoid emitting useless diagnostics. 4361 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4362 // C99 6.7.8p4. All file scoped initializers need to be constant. 4363 CheckForConstantInitializer(Init, DclT); 4364 } 4365 } 4366 // If the type changed, it means we had an incomplete type that was 4367 // completed by the initializer. For example: 4368 // int ary[] = { 1, 3, 5 }; 4369 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4370 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4371 VDecl->setType(DclT); 4372 Init->setType(DclT); 4373 } 4374 4375 4376 // If this variable is a local declaration with record type, make sure it 4377 // doesn't have a flexible member initialization. We only support this as a 4378 // global/static definition. 4379 if (VDecl->hasLocalStorage()) 4380 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4381 if (RT->getDecl()->hasFlexibleArrayMember() && isa<InitListExpr>(Init)) { 4382 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4383 VDecl->setInvalidDecl(); 4384 } 4385 4386 // Check any implicit conversions within the expression. 4387 CheckImplicitConversions(Init, VDecl->getLocation()); 4388 4389 Init = MaybeCreateCXXExprWithTemporaries(Init); 4390 // Attach the initializer to the decl. 4391 VDecl->setInit(Init); 4392 4393 if (getLangOptions().CPlusPlus) { 4394 if (!VDecl->isInvalidDecl() && 4395 !VDecl->getDeclContext()->isDependentContext() && 4396 VDecl->hasGlobalStorage() && !VDecl->isStaticLocal() && 4397 !Init->isConstantInitializer(Context, 4398 VDecl->getType()->isReferenceType())) 4399 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4400 << Init->getSourceRange(); 4401 4402 // Make sure we mark the destructor as used if necessary. 4403 QualType InitType = VDecl->getType(); 4404 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4405 InitType = Context.getBaseElementType(Array); 4406 if (const RecordType *Record = InitType->getAs<RecordType>()) 4407 FinalizeVarWithDestructor(VDecl, Record); 4408 } 4409 4410 return; 4411} 4412 4413/// ActOnInitializerError - Given that there was an error parsing an 4414/// initializer for the given declaration, try to return to some form 4415/// of sanity. 4416void Sema::ActOnInitializerError(Decl *D) { 4417 // Our main concern here is re-establishing invariants like "a 4418 // variable's type is either dependent or complete". 4419 if (!D || D->isInvalidDecl()) return; 4420 4421 VarDecl *VD = dyn_cast<VarDecl>(D); 4422 if (!VD) return; 4423 4424 QualType Ty = VD->getType(); 4425 if (Ty->isDependentType()) return; 4426 4427 // Require a complete type. 4428 if (RequireCompleteType(VD->getLocation(), 4429 Context.getBaseElementType(Ty), 4430 diag::err_typecheck_decl_incomplete_type)) { 4431 VD->setInvalidDecl(); 4432 return; 4433 } 4434 4435 // Require an abstract type. 4436 if (RequireNonAbstractType(VD->getLocation(), Ty, 4437 diag::err_abstract_type_in_decl, 4438 AbstractVariableType)) { 4439 VD->setInvalidDecl(); 4440 return; 4441 } 4442 4443 // Don't bother complaining about constructors or destructors, 4444 // though. 4445} 4446 4447void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4448 bool TypeContainsUndeducedAuto) { 4449 // If there is no declaration, there was an error parsing it. Just ignore it. 4450 if (RealDecl == 0) 4451 return; 4452 4453 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4454 QualType Type = Var->getType(); 4455 4456 // C++0x [dcl.spec.auto]p3 4457 if (TypeContainsUndeducedAuto) { 4458 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4459 << Var->getDeclName() << Type; 4460 Var->setInvalidDecl(); 4461 return; 4462 } 4463 4464 switch (Var->isThisDeclarationADefinition()) { 4465 case VarDecl::Definition: 4466 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4467 break; 4468 4469 // We have an out-of-line definition of a static data member 4470 // that has an in-class initializer, so we type-check this like 4471 // a declaration. 4472 // 4473 // Fall through 4474 4475 case VarDecl::DeclarationOnly: 4476 // It's only a declaration. 4477 4478 // Block scope. C99 6.7p7: If an identifier for an object is 4479 // declared with no linkage (C99 6.2.2p6), the type for the 4480 // object shall be complete. 4481 if (!Type->isDependentType() && Var->isLocalVarDecl() && 4482 !Var->getLinkage() && !Var->isInvalidDecl() && 4483 RequireCompleteType(Var->getLocation(), Type, 4484 diag::err_typecheck_decl_incomplete_type)) 4485 Var->setInvalidDecl(); 4486 4487 // Make sure that the type is not abstract. 4488 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4489 RequireNonAbstractType(Var->getLocation(), Type, 4490 diag::err_abstract_type_in_decl, 4491 AbstractVariableType)) 4492 Var->setInvalidDecl(); 4493 return; 4494 4495 case VarDecl::TentativeDefinition: 4496 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4497 // object that has file scope without an initializer, and without a 4498 // storage-class specifier or with the storage-class specifier "static", 4499 // constitutes a tentative definition. Note: A tentative definition with 4500 // external linkage is valid (C99 6.2.2p5). 4501 if (!Var->isInvalidDecl()) { 4502 if (const IncompleteArrayType *ArrayT 4503 = Context.getAsIncompleteArrayType(Type)) { 4504 if (RequireCompleteType(Var->getLocation(), 4505 ArrayT->getElementType(), 4506 diag::err_illegal_decl_array_incomplete_type)) 4507 Var->setInvalidDecl(); 4508 } else if (Var->getStorageClass() == SC_Static) { 4509 // C99 6.9.2p3: If the declaration of an identifier for an object is 4510 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4511 // declared type shall not be an incomplete type. 4512 // NOTE: code such as the following 4513 // static struct s; 4514 // struct s { int a; }; 4515 // is accepted by gcc. Hence here we issue a warning instead of 4516 // an error and we do not invalidate the static declaration. 4517 // NOTE: to avoid multiple warnings, only check the first declaration. 4518 if (Var->getPreviousDeclaration() == 0) 4519 RequireCompleteType(Var->getLocation(), Type, 4520 diag::ext_typecheck_decl_incomplete_type); 4521 } 4522 } 4523 4524 // Record the tentative definition; we're done. 4525 if (!Var->isInvalidDecl()) 4526 TentativeDefinitions.push_back(Var); 4527 return; 4528 } 4529 4530 // Provide a specific diagnostic for uninitialized variable 4531 // definitions with incomplete array type. 4532 if (Type->isIncompleteArrayType()) { 4533 Diag(Var->getLocation(), 4534 diag::err_typecheck_incomplete_array_needs_initializer); 4535 Var->setInvalidDecl(); 4536 return; 4537 } 4538 4539 // Provide a specific diagnostic for uninitialized variable 4540 // definitions with reference type. 4541 if (Type->isReferenceType()) { 4542 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4543 << Var->getDeclName() 4544 << SourceRange(Var->getLocation(), Var->getLocation()); 4545 Var->setInvalidDecl(); 4546 return; 4547 } 4548 4549 // Do not attempt to type-check the default initializer for a 4550 // variable with dependent type. 4551 if (Type->isDependentType()) 4552 return; 4553 4554 if (Var->isInvalidDecl()) 4555 return; 4556 4557 if (RequireCompleteType(Var->getLocation(), 4558 Context.getBaseElementType(Type), 4559 diag::err_typecheck_decl_incomplete_type)) { 4560 Var->setInvalidDecl(); 4561 return; 4562 } 4563 4564 // The variable can not have an abstract class type. 4565 if (RequireNonAbstractType(Var->getLocation(), Type, 4566 diag::err_abstract_type_in_decl, 4567 AbstractVariableType)) { 4568 Var->setInvalidDecl(); 4569 return; 4570 } 4571 4572 const RecordType *Record 4573 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4574 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4575 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4576 // C++03 [dcl.init]p9: 4577 // If no initializer is specified for an object, and the 4578 // object is of (possibly cv-qualified) non-POD class type (or 4579 // array thereof), the object shall be default-initialized; if 4580 // the object is of const-qualified type, the underlying class 4581 // type shall have a user-declared default 4582 // constructor. Otherwise, if no initializer is specified for 4583 // a non- static object, the object and its subobjects, if 4584 // any, have an indeterminate initial value); if the object 4585 // or any of its subobjects are of const-qualified type, the 4586 // program is ill-formed. 4587 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4588 } else { 4589 // Check for jumps past the implicit initializer. C++0x 4590 // clarifies that this applies to a "variable with automatic 4591 // storage duration", not a "local variable". 4592 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4593 getCurFunction()->setHasBranchProtectedScope(); 4594 4595 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4596 InitializationKind Kind 4597 = InitializationKind::CreateDefault(Var->getLocation()); 4598 4599 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4600 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4601 MultiExprArg(*this, 0, 0)); 4602 if (Init.isInvalid()) 4603 Var->setInvalidDecl(); 4604 else if (Init.get()) { 4605 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4606 4607 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4608 Var->hasGlobalStorage() && !Var->isStaticLocal() && 4609 !Var->getDeclContext()->isDependentContext() && 4610 !Var->getInit()->isConstantInitializer(Context, false)) 4611 Diag(Var->getLocation(), diag::warn_global_constructor); 4612 } 4613 } 4614 4615 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4616 FinalizeVarWithDestructor(Var, Record); 4617 } 4618} 4619 4620Sema::DeclGroupPtrTy 4621Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4622 Decl **Group, unsigned NumDecls) { 4623 llvm::SmallVector<Decl*, 8> Decls; 4624 4625 if (DS.isTypeSpecOwned()) 4626 Decls.push_back(DS.getRepAsDecl()); 4627 4628 for (unsigned i = 0; i != NumDecls; ++i) 4629 if (Decl *D = Group[i]) 4630 Decls.push_back(D); 4631 4632 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4633 Decls.data(), Decls.size())); 4634} 4635 4636 4637/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4638/// to introduce parameters into function prototype scope. 4639Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4640 const DeclSpec &DS = D.getDeclSpec(); 4641 4642 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4643 VarDecl::StorageClass StorageClass = SC_None; 4644 VarDecl::StorageClass StorageClassAsWritten = SC_None; 4645 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4646 StorageClass = SC_Register; 4647 StorageClassAsWritten = SC_Register; 4648 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4649 Diag(DS.getStorageClassSpecLoc(), 4650 diag::err_invalid_storage_class_in_func_decl); 4651 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4652 } 4653 4654 if (D.getDeclSpec().isThreadSpecified()) 4655 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4656 4657 DiagnoseFunctionSpecifiers(D); 4658 4659 // Check that there are no default arguments inside the type of this 4660 // parameter (C++ only). 4661 if (getLangOptions().CPlusPlus) 4662 CheckExtraCXXDefaultArguments(D); 4663 4664 TagDecl *OwnedDecl = 0; 4665 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4666 QualType parmDeclType = TInfo->getType(); 4667 4668 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4669 // C++ [dcl.fct]p6: 4670 // Types shall not be defined in return or parameter types. 4671 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4672 << Context.getTypeDeclType(OwnedDecl); 4673 } 4674 4675 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4676 IdentifierInfo *II = D.getIdentifier(); 4677 if (II) { 4678 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4679 ForRedeclaration); 4680 LookupName(R, S); 4681 if (R.isSingleResult()) { 4682 NamedDecl *PrevDecl = R.getFoundDecl(); 4683 if (PrevDecl->isTemplateParameter()) { 4684 // Maybe we will complain about the shadowed template parameter. 4685 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4686 // Just pretend that we didn't see the previous declaration. 4687 PrevDecl = 0; 4688 } else if (S->isDeclScope(PrevDecl)) { 4689 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4690 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4691 4692 // Recover by removing the name 4693 II = 0; 4694 D.SetIdentifier(0, D.getIdentifierLoc()); 4695 D.setInvalidType(true); 4696 } 4697 } 4698 } 4699 4700 // Temporarily put parameter variables in the translation unit, not 4701 // the enclosing context. This prevents them from accidentally 4702 // looking like class members in C++. 4703 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4704 TInfo, parmDeclType, II, 4705 D.getIdentifierLoc(), 4706 StorageClass, StorageClassAsWritten); 4707 4708 if (D.isInvalidType()) 4709 New->setInvalidDecl(); 4710 4711 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4712 if (D.getCXXScopeSpec().isSet()) { 4713 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4714 << D.getCXXScopeSpec().getRange(); 4715 New->setInvalidDecl(); 4716 } 4717 4718 // Add the parameter declaration into this scope. 4719 S->AddDecl(New); 4720 if (II) 4721 IdResolver.AddDecl(New); 4722 4723 ProcessDeclAttributes(S, New, D); 4724 4725 if (New->hasAttr<BlocksAttr>()) { 4726 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4727 } 4728 return New; 4729} 4730 4731/// \brief Synthesizes a variable for a parameter arising from a 4732/// typedef. 4733ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4734 SourceLocation Loc, 4735 QualType T) { 4736 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4737 T, Context.getTrivialTypeSourceInfo(T, Loc), 4738 SC_None, SC_None, 0); 4739 Param->setImplicit(); 4740 return Param; 4741} 4742 4743void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 4744 ParmVarDecl * const *ParamEnd) { 4745 if (Diags.getDiagnosticLevel(diag::warn_unused_parameter) == 4746 Diagnostic::Ignored) 4747 return; 4748 4749 // Don't diagnose unused-parameter errors in template instantiations; we 4750 // will already have done so in the template itself. 4751 if (!ActiveTemplateInstantiations.empty()) 4752 return; 4753 4754 for (; Param != ParamEnd; ++Param) { 4755 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 4756 !(*Param)->hasAttr<UnusedAttr>()) { 4757 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 4758 << (*Param)->getDeclName(); 4759 } 4760 } 4761} 4762 4763ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4764 TypeSourceInfo *TSInfo, QualType T, 4765 IdentifierInfo *Name, 4766 SourceLocation NameLoc, 4767 VarDecl::StorageClass StorageClass, 4768 VarDecl::StorageClass StorageClassAsWritten) { 4769 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4770 adjustParameterType(T), TSInfo, 4771 StorageClass, StorageClassAsWritten, 4772 0); 4773 4774 // Parameters can not be abstract class types. 4775 // For record types, this is done by the AbstractClassUsageDiagnoser once 4776 // the class has been completely parsed. 4777 if (!CurContext->isRecord() && 4778 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4779 AbstractParamType)) 4780 New->setInvalidDecl(); 4781 4782 // Parameter declarators cannot be interface types. All ObjC objects are 4783 // passed by reference. 4784 if (T->isObjCObjectType()) { 4785 Diag(NameLoc, 4786 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4787 New->setInvalidDecl(); 4788 } 4789 4790 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4791 // duration shall not be qualified by an address-space qualifier." 4792 // Since all parameters have automatic store duration, they can not have 4793 // an address space. 4794 if (T.getAddressSpace() != 0) { 4795 Diag(NameLoc, diag::err_arg_with_address_space); 4796 New->setInvalidDecl(); 4797 } 4798 4799 return New; 4800} 4801 4802void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4803 SourceLocation LocAfterDecls) { 4804 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4805 "Not a function declarator!"); 4806 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4807 4808 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4809 // for a K&R function. 4810 if (!FTI.hasPrototype) { 4811 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4812 --i; 4813 if (FTI.ArgInfo[i].Param == 0) { 4814 llvm::SmallString<256> Code; 4815 llvm::raw_svector_ostream(Code) << " int " 4816 << FTI.ArgInfo[i].Ident->getName() 4817 << ";\n"; 4818 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4819 << FTI.ArgInfo[i].Ident 4820 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4821 4822 // Implicitly declare the argument as type 'int' for lack of a better 4823 // type. 4824 DeclSpec DS; 4825 const char* PrevSpec; // unused 4826 unsigned DiagID; // unused 4827 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4828 PrevSpec, DiagID); 4829 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4830 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4831 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4832 } 4833 } 4834 } 4835} 4836 4837Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4838 Declarator &D) { 4839 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4840 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4841 "Not a function declarator!"); 4842 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4843 4844 if (FTI.hasPrototype) { 4845 // FIXME: Diagnose arguments without names in C. 4846 } 4847 4848 Scope *ParentScope = FnBodyScope->getParent(); 4849 4850 Decl *DP = HandleDeclarator(ParentScope, D, 4851 MultiTemplateParamsArg(*this), 4852 /*IsFunctionDefinition=*/true); 4853 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4854} 4855 4856static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4857 // Don't warn about invalid declarations. 4858 if (FD->isInvalidDecl()) 4859 return false; 4860 4861 // Or declarations that aren't global. 4862 if (!FD->isGlobal()) 4863 return false; 4864 4865 // Don't warn about C++ member functions. 4866 if (isa<CXXMethodDecl>(FD)) 4867 return false; 4868 4869 // Don't warn about 'main'. 4870 if (FD->isMain()) 4871 return false; 4872 4873 // Don't warn about inline functions. 4874 if (FD->isInlineSpecified()) 4875 return false; 4876 4877 // Don't warn about function templates. 4878 if (FD->getDescribedFunctionTemplate()) 4879 return false; 4880 4881 // Don't warn about function template specializations. 4882 if (FD->isFunctionTemplateSpecialization()) 4883 return false; 4884 4885 bool MissingPrototype = true; 4886 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4887 Prev; Prev = Prev->getPreviousDeclaration()) { 4888 // Ignore any declarations that occur in function or method 4889 // scope, because they aren't visible from the header. 4890 if (Prev->getDeclContext()->isFunctionOrMethod()) 4891 continue; 4892 4893 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4894 break; 4895 } 4896 4897 return MissingPrototype; 4898} 4899 4900Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4901 // Clear the last template instantiation error context. 4902 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4903 4904 if (!D) 4905 return D; 4906 FunctionDecl *FD = 0; 4907 4908 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4909 FD = FunTmpl->getTemplatedDecl(); 4910 else 4911 FD = cast<FunctionDecl>(D); 4912 4913 // Enter a new function scope 4914 PushFunctionScope(); 4915 4916 // See if this is a redefinition. 4917 // But don't complain if we're in GNU89 mode and the previous definition 4918 // was an extern inline function. 4919 const FunctionDecl *Definition; 4920 if (FD->hasBody(Definition) && 4921 !canRedefineFunction(Definition, getLangOptions())) { 4922 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 4923 Definition->getStorageClass() == SC_Extern) 4924 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 4925 << FD->getDeclName() << getLangOptions().CPlusPlus; 4926 else 4927 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4928 Diag(Definition->getLocation(), diag::note_previous_definition); 4929 } 4930 4931 // Builtin functions cannot be defined. 4932 if (unsigned BuiltinID = FD->getBuiltinID()) { 4933 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4934 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4935 FD->setInvalidDecl(); 4936 } 4937 } 4938 4939 // The return type of a function definition must be complete 4940 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4941 QualType ResultType = FD->getResultType(); 4942 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4943 !FD->isInvalidDecl() && 4944 RequireCompleteType(FD->getLocation(), ResultType, 4945 diag::err_func_def_incomplete_result)) 4946 FD->setInvalidDecl(); 4947 4948 // GNU warning -Wmissing-prototypes: 4949 // Warn if a global function is defined without a previous 4950 // prototype declaration. This warning is issued even if the 4951 // definition itself provides a prototype. The aim is to detect 4952 // global functions that fail to be declared in header files. 4953 if (ShouldWarnAboutMissingPrototype(FD)) 4954 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4955 4956 if (FnBodyScope) 4957 PushDeclContext(FnBodyScope, FD); 4958 4959 // Check the validity of our function parameters 4960 CheckParmsForFunctionDef(FD); 4961 4962 bool ShouldCheckShadow = 4963 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4964 4965 // Introduce our parameters into the function scope 4966 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4967 ParmVarDecl *Param = FD->getParamDecl(p); 4968 Param->setOwningFunction(FD); 4969 4970 // If this has an identifier, add it to the scope stack. 4971 if (Param->getIdentifier() && FnBodyScope) { 4972 if (ShouldCheckShadow) 4973 CheckShadow(FnBodyScope, Param); 4974 4975 PushOnScopeChains(Param, FnBodyScope); 4976 } 4977 } 4978 4979 // Checking attributes of current function definition 4980 // dllimport attribute. 4981 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 4982 if (DA && (!FD->getAttr<DLLExportAttr>())) { 4983 // dllimport attribute cannot be directly applied to definition. 4984 if (!DA->isInherited()) { 4985 Diag(FD->getLocation(), 4986 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4987 << "dllimport"; 4988 FD->setInvalidDecl(); 4989 return FD; 4990 } 4991 4992 // Visual C++ appears to not think this is an issue, so only issue 4993 // a warning when Microsoft extensions are disabled. 4994 if (!LangOpts.Microsoft) { 4995 // If a symbol previously declared dllimport is later defined, the 4996 // attribute is ignored in subsequent references, and a warning is 4997 // emitted. 4998 Diag(FD->getLocation(), 4999 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5000 << FD->getName() << "dllimport"; 5001 } 5002 } 5003 return FD; 5004} 5005 5006/// \brief Given the set of return statements within a function body, 5007/// compute the variables that are subject to the named return value 5008/// optimization. 5009/// 5010/// Each of the variables that is subject to the named return value 5011/// optimization will be marked as NRVO variables in the AST, and any 5012/// return statement that has a marked NRVO variable as its NRVO candidate can 5013/// use the named return value optimization. 5014/// 5015/// This function applies a very simplistic algorithm for NRVO: if every return 5016/// statement in the function has the same NRVO candidate, that candidate is 5017/// the NRVO variable. 5018/// 5019/// FIXME: Employ a smarter algorithm that accounts for multiple return 5020/// statements and the lifetimes of the NRVO candidates. We should be able to 5021/// find a maximal set of NRVO variables. 5022static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5023 ReturnStmt **Returns = Scope->Returns.data(); 5024 5025 const VarDecl *NRVOCandidate = 0; 5026 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5027 if (!Returns[I]->getNRVOCandidate()) 5028 return; 5029 5030 if (!NRVOCandidate) 5031 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5032 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5033 return; 5034 } 5035 5036 if (NRVOCandidate) 5037 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5038} 5039 5040Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5041 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5042} 5043 5044Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5045 bool IsInstantiation) { 5046 FunctionDecl *FD = 0; 5047 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5048 if (FunTmpl) 5049 FD = FunTmpl->getTemplatedDecl(); 5050 else 5051 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5052 5053 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5054 5055 if (FD) { 5056 FD->setBody(Body); 5057 if (FD->isMain()) { 5058 // C and C++ allow for main to automagically return 0. 5059 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5060 FD->setHasImplicitReturnZero(true); 5061 WP.disableCheckFallThrough(); 5062 } 5063 5064 if (!FD->isInvalidDecl()) { 5065 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5066 5067 // If this is a constructor, we need a vtable. 5068 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5069 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5070 5071 ComputeNRVO(Body, getCurFunction()); 5072 } 5073 5074 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5075 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5076 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5077 MD->setBody(Body); 5078 MD->setEndLoc(Body->getLocEnd()); 5079 if (!MD->isInvalidDecl()) 5080 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5081 } else { 5082 return 0; 5083 } 5084 5085 // Verify and clean out per-function state. 5086 5087 // Check goto/label use. 5088 FunctionScopeInfo *CurFn = getCurFunction(); 5089 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 5090 I = CurFn->LabelMap.begin(), E = CurFn->LabelMap.end(); I != E; ++I) { 5091 LabelStmt *L = I->second; 5092 5093 // Verify that we have no forward references left. If so, there was a goto 5094 // or address of a label taken, but no definition of it. Label fwd 5095 // definitions are indicated with a null substmt. 5096 if (L->getSubStmt() != 0) { 5097 if (!L->isUsed()) 5098 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 5099 continue; 5100 } 5101 5102 // Emit error. 5103 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 5104 5105 // At this point, we have gotos that use the bogus label. Stitch it into 5106 // the function body so that they aren't leaked and that the AST is well 5107 // formed. 5108 if (Body == 0) { 5109 // The whole function wasn't parsed correctly. 5110 continue; 5111 } 5112 5113 // Otherwise, the body is valid: we want to stitch the label decl into the 5114 // function somewhere so that it is properly owned and so that the goto 5115 // has a valid target. Do this by creating a new compound stmt with the 5116 // label in it. 5117 5118 // Give the label a sub-statement. 5119 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 5120 5121 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 5122 cast<CXXTryStmt>(Body)->getTryBlock() : 5123 cast<CompoundStmt>(Body); 5124 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 5125 Compound->body_end()); 5126 Elements.push_back(L); 5127 Compound->setStmts(Context, Elements.data(), Elements.size()); 5128 } 5129 5130 if (Body) { 5131 // C++ constructors that have function-try-blocks can't have return 5132 // statements in the handlers of that block. (C++ [except.handle]p14) 5133 // Verify this. 5134 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5135 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5136 5137 // Verify that that gotos and switch cases don't jump into scopes illegally. 5138 // Verify that that gotos and switch cases don't jump into scopes illegally. 5139 if (getCurFunction()->NeedsScopeChecking() && 5140 !dcl->isInvalidDecl() && 5141 !hasAnyErrorsInThisFunction()) 5142 DiagnoseInvalidJumps(Body); 5143 5144 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5145 if (!Destructor->getParent()->isDependentType()) 5146 CheckDestructor(Destructor); 5147 5148 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5149 Destructor->getParent()); 5150 } 5151 5152 // If any errors have occurred, clear out any temporaries that may have 5153 // been leftover. This ensures that these temporaries won't be picked up for 5154 // deletion in some later function. 5155 if (PP.getDiagnostics().hasErrorOccurred()) 5156 ExprTemporaries.clear(); 5157 else if (!isa<FunctionTemplateDecl>(dcl)) { 5158 // Since the body is valid, issue any analysis-based warnings that are 5159 // enabled. 5160 QualType ResultType; 5161 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 5162 AnalysisWarnings.IssueWarnings(WP, FD); 5163 } else { 5164 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 5165 AnalysisWarnings.IssueWarnings(WP, MD); 5166 } 5167 } 5168 5169 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5170 } 5171 5172 if (!IsInstantiation) 5173 PopDeclContext(); 5174 5175 PopFunctionOrBlockScope(); 5176 5177 // If any errors have occurred, clear out any temporaries that may have 5178 // been leftover. This ensures that these temporaries won't be picked up for 5179 // deletion in some later function. 5180 if (getDiagnostics().hasErrorOccurred()) 5181 ExprTemporaries.clear(); 5182 5183 return dcl; 5184} 5185 5186/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5187/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5188NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5189 IdentifierInfo &II, Scope *S) { 5190 // Before we produce a declaration for an implicitly defined 5191 // function, see whether there was a locally-scoped declaration of 5192 // this name as a function or variable. If so, use that 5193 // (non-visible) declaration, and complain about it. 5194 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5195 = LocallyScopedExternalDecls.find(&II); 5196 if (Pos != LocallyScopedExternalDecls.end()) { 5197 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5198 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5199 return Pos->second; 5200 } 5201 5202 // Extension in C99. Legal in C90, but warn about it. 5203 if (II.getName().startswith("__builtin_")) 5204 Diag(Loc, diag::warn_builtin_unknown) << &II; 5205 else if (getLangOptions().C99) 5206 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5207 else 5208 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5209 5210 // Set a Declarator for the implicit definition: int foo(); 5211 const char *Dummy; 5212 DeclSpec DS; 5213 unsigned DiagID; 5214 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5215 Error = Error; // Silence warning. 5216 assert(!Error && "Error setting up implicit decl!"); 5217 Declarator D(DS, Declarator::BlockContext); 5218 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5219 0, 0, false, SourceLocation(), 5220 false, 0,0,0, Loc, Loc, D), 5221 SourceLocation()); 5222 D.SetIdentifier(&II, Loc); 5223 5224 // Insert this function into translation-unit scope. 5225 5226 DeclContext *PrevDC = CurContext; 5227 CurContext = Context.getTranslationUnitDecl(); 5228 5229 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5230 FD->setImplicit(); 5231 5232 CurContext = PrevDC; 5233 5234 AddKnownFunctionAttributes(FD); 5235 5236 return FD; 5237} 5238 5239/// \brief Adds any function attributes that we know a priori based on 5240/// the declaration of this function. 5241/// 5242/// These attributes can apply both to implicitly-declared builtins 5243/// (like __builtin___printf_chk) or to library-declared functions 5244/// like NSLog or printf. 5245void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5246 if (FD->isInvalidDecl()) 5247 return; 5248 5249 // If this is a built-in function, map its builtin attributes to 5250 // actual attributes. 5251 if (unsigned BuiltinID = FD->getBuiltinID()) { 5252 // Handle printf-formatting attributes. 5253 unsigned FormatIdx; 5254 bool HasVAListArg; 5255 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5256 if (!FD->getAttr<FormatAttr>()) 5257 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5258 "printf", FormatIdx+1, 5259 HasVAListArg ? 0 : FormatIdx+2)); 5260 } 5261 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5262 HasVAListArg)) { 5263 if (!FD->getAttr<FormatAttr>()) 5264 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5265 "scanf", FormatIdx+1, 5266 HasVAListArg ? 0 : FormatIdx+2)); 5267 } 5268 5269 // Mark const if we don't care about errno and that is the only 5270 // thing preventing the function from being const. This allows 5271 // IRgen to use LLVM intrinsics for such functions. 5272 if (!getLangOptions().MathErrno && 5273 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5274 if (!FD->getAttr<ConstAttr>()) 5275 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5276 } 5277 5278 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5279 FD->setType(Context.getNoReturnType(FD->getType())); 5280 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5281 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5282 if (Context.BuiltinInfo.isConst(BuiltinID)) 5283 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5284 } 5285 5286 IdentifierInfo *Name = FD->getIdentifier(); 5287 if (!Name) 5288 return; 5289 if ((!getLangOptions().CPlusPlus && 5290 FD->getDeclContext()->isTranslationUnit()) || 5291 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5292 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5293 LinkageSpecDecl::lang_c)) { 5294 // Okay: this could be a libc/libm/Objective-C function we know 5295 // about. 5296 } else 5297 return; 5298 5299 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5300 // FIXME: NSLog and NSLogv should be target specific 5301 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5302 // FIXME: We known better than our headers. 5303 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5304 } else 5305 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5306 "printf", 1, 5307 Name->isStr("NSLogv") ? 0 : 2)); 5308 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5309 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5310 // target-specific builtins, perhaps? 5311 if (!FD->getAttr<FormatAttr>()) 5312 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5313 "printf", 2, 5314 Name->isStr("vasprintf") ? 0 : 3)); 5315 } 5316} 5317 5318TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5319 TypeSourceInfo *TInfo) { 5320 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5321 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5322 5323 if (!TInfo) { 5324 assert(D.isInvalidType() && "no declarator info for valid type"); 5325 TInfo = Context.getTrivialTypeSourceInfo(T); 5326 } 5327 5328 // Scope manipulation handled by caller. 5329 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5330 D.getIdentifierLoc(), 5331 D.getIdentifier(), 5332 TInfo); 5333 5334 if (const TagType *TT = T->getAs<TagType>()) { 5335 TagDecl *TD = TT->getDecl(); 5336 5337 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5338 // keep track of the TypedefDecl. 5339 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5340 TD->setTypedefForAnonDecl(NewTD); 5341 } 5342 5343 if (D.isInvalidType()) 5344 NewTD->setInvalidDecl(); 5345 return NewTD; 5346} 5347 5348 5349/// \brief Determine whether a tag with a given kind is acceptable 5350/// as a redeclaration of the given tag declaration. 5351/// 5352/// \returns true if the new tag kind is acceptable, false otherwise. 5353bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5354 TagTypeKind NewTag, 5355 SourceLocation NewTagLoc, 5356 const IdentifierInfo &Name) { 5357 // C++ [dcl.type.elab]p3: 5358 // The class-key or enum keyword present in the 5359 // elaborated-type-specifier shall agree in kind with the 5360 // declaration to which the name in the elaborated-type-specifier 5361 // refers. This rule also applies to the form of 5362 // elaborated-type-specifier that declares a class-name or 5363 // friend class since it can be construed as referring to the 5364 // definition of the class. Thus, in any 5365 // elaborated-type-specifier, the enum keyword shall be used to 5366 // refer to an enumeration (7.2), the union class-key shall be 5367 // used to refer to a union (clause 9), and either the class or 5368 // struct class-key shall be used to refer to a class (clause 9) 5369 // declared using the class or struct class-key. 5370 TagTypeKind OldTag = Previous->getTagKind(); 5371 if (OldTag == NewTag) 5372 return true; 5373 5374 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5375 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5376 // Warn about the struct/class tag mismatch. 5377 bool isTemplate = false; 5378 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5379 isTemplate = Record->getDescribedClassTemplate(); 5380 5381 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5382 << (NewTag == TTK_Class) 5383 << isTemplate << &Name 5384 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5385 OldTag == TTK_Class? "class" : "struct"); 5386 Diag(Previous->getLocation(), diag::note_previous_use); 5387 return true; 5388 } 5389 return false; 5390} 5391 5392/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5393/// former case, Name will be non-null. In the later case, Name will be null. 5394/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5395/// reference/declaration/definition of a tag. 5396Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5397 SourceLocation KWLoc, CXXScopeSpec &SS, 5398 IdentifierInfo *Name, SourceLocation NameLoc, 5399 AttributeList *Attr, AccessSpecifier AS, 5400 MultiTemplateParamsArg TemplateParameterLists, 5401 bool &OwnedDecl, bool &IsDependent, bool ScopedEnum, 5402 TypeResult UnderlyingType) { 5403 // If this is not a definition, it must have a name. 5404 assert((Name != 0 || TUK == TUK_Definition) && 5405 "Nameless record must be a definition!"); 5406 5407 OwnedDecl = false; 5408 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5409 5410 // FIXME: Check explicit specializations more carefully. 5411 bool isExplicitSpecialization = false; 5412 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5413 bool Invalid = false; 5414 if (TUK != TUK_Reference) { 5415 if (TemplateParameterList *TemplateParams 5416 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5417 (TemplateParameterList**)TemplateParameterLists.get(), 5418 TemplateParameterLists.size(), 5419 TUK == TUK_Friend, 5420 isExplicitSpecialization, 5421 Invalid)) { 5422 // All but one template parameter lists have been matching. 5423 --NumMatchedTemplateParamLists; 5424 5425 if (TemplateParams->size() > 0) { 5426 // This is a declaration or definition of a class template (which may 5427 // be a member of another template). 5428 if (Invalid) 5429 return 0; 5430 5431 OwnedDecl = false; 5432 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5433 SS, Name, NameLoc, Attr, 5434 TemplateParams, 5435 AS); 5436 TemplateParameterLists.release(); 5437 return Result.get(); 5438 } else { 5439 // The "template<>" header is extraneous. 5440 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5441 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5442 isExplicitSpecialization = true; 5443 } 5444 } 5445 } 5446 5447 // Figure out the underlying type if this a enum declaration. We need to do 5448 // this early, because it's needed to detect if this is an incompatible 5449 // redeclaration. 5450 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 5451 5452 if (Kind == TTK_Enum) { 5453 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 5454 // No underlying type explicitly specified, or we failed to parse the 5455 // type, default to int. 5456 EnumUnderlying = Context.IntTy.getTypePtr(); 5457 else if (UnderlyingType.get()) { 5458 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 5459 // integral type; any cv-qualification is ignored. 5460 TypeSourceInfo *TI = 0; 5461 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 5462 EnumUnderlying = TI; 5463 5464 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 5465 5466 if (!T->isDependentType() && !T->isIntegralType(Context)) { 5467 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 5468 << T; 5469 // Recover by falling back to int. 5470 EnumUnderlying = Context.IntTy.getTypePtr(); 5471 } 5472 } 5473 } 5474 5475 DeclContext *SearchDC = CurContext; 5476 DeclContext *DC = CurContext; 5477 bool isStdBadAlloc = false; 5478 5479 RedeclarationKind Redecl = ForRedeclaration; 5480 if (TUK == TUK_Friend || TUK == TUK_Reference) 5481 Redecl = NotForRedeclaration; 5482 5483 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5484 5485 if (Name && SS.isNotEmpty()) { 5486 // We have a nested-name tag ('struct foo::bar'). 5487 5488 // Check for invalid 'foo::'. 5489 if (SS.isInvalid()) { 5490 Name = 0; 5491 goto CreateNewDecl; 5492 } 5493 5494 // If this is a friend or a reference to a class in a dependent 5495 // context, don't try to make a decl for it. 5496 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5497 DC = computeDeclContext(SS, false); 5498 if (!DC) { 5499 IsDependent = true; 5500 return 0; 5501 } 5502 } else { 5503 DC = computeDeclContext(SS, true); 5504 if (!DC) { 5505 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5506 << SS.getRange(); 5507 return 0; 5508 } 5509 } 5510 5511 if (RequireCompleteDeclContext(SS, DC)) 5512 return 0; 5513 5514 SearchDC = DC; 5515 // Look-up name inside 'foo::'. 5516 LookupQualifiedName(Previous, DC); 5517 5518 if (Previous.isAmbiguous()) 5519 return 0; 5520 5521 if (Previous.empty()) { 5522 // Name lookup did not find anything. However, if the 5523 // nested-name-specifier refers to the current instantiation, 5524 // and that current instantiation has any dependent base 5525 // classes, we might find something at instantiation time: treat 5526 // this as a dependent elaborated-type-specifier. 5527 if (Previous.wasNotFoundInCurrentInstantiation()) { 5528 IsDependent = true; 5529 return 0; 5530 } 5531 5532 // A tag 'foo::bar' must already exist. 5533 Diag(NameLoc, diag::err_not_tag_in_scope) 5534 << Kind << Name << DC << SS.getRange(); 5535 Name = 0; 5536 Invalid = true; 5537 goto CreateNewDecl; 5538 } 5539 } else if (Name) { 5540 // If this is a named struct, check to see if there was a previous forward 5541 // declaration or definition. 5542 // FIXME: We're looking into outer scopes here, even when we 5543 // shouldn't be. Doing so can result in ambiguities that we 5544 // shouldn't be diagnosing. 5545 LookupName(Previous, S); 5546 5547 // Note: there used to be some attempt at recovery here. 5548 if (Previous.isAmbiguous()) 5549 return 0; 5550 5551 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5552 // FIXME: This makes sure that we ignore the contexts associated 5553 // with C structs, unions, and enums when looking for a matching 5554 // tag declaration or definition. See the similar lookup tweak 5555 // in Sema::LookupName; is there a better way to deal with this? 5556 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5557 SearchDC = SearchDC->getParent(); 5558 } 5559 } else if (S->isFunctionPrototypeScope()) { 5560 // If this is an enum declaration in function prototype scope, set its 5561 // initial context to the translation unit. 5562 SearchDC = Context.getTranslationUnitDecl(); 5563 } 5564 5565 if (Previous.isSingleResult() && 5566 Previous.getFoundDecl()->isTemplateParameter()) { 5567 // Maybe we will complain about the shadowed template parameter. 5568 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5569 // Just pretend that we didn't see the previous declaration. 5570 Previous.clear(); 5571 } 5572 5573 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5574 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5575 // This is a declaration of or a reference to "std::bad_alloc". 5576 isStdBadAlloc = true; 5577 5578 if (Previous.empty() && StdBadAlloc) { 5579 // std::bad_alloc has been implicitly declared (but made invisible to 5580 // name lookup). Fill in this implicit declaration as the previous 5581 // declaration, so that the declarations get chained appropriately. 5582 Previous.addDecl(getStdBadAlloc()); 5583 } 5584 } 5585 5586 // If we didn't find a previous declaration, and this is a reference 5587 // (or friend reference), move to the correct scope. In C++, we 5588 // also need to do a redeclaration lookup there, just in case 5589 // there's a shadow friend decl. 5590 if (Name && Previous.empty() && 5591 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5592 if (Invalid) goto CreateNewDecl; 5593 assert(SS.isEmpty()); 5594 5595 if (TUK == TUK_Reference) { 5596 // C++ [basic.scope.pdecl]p5: 5597 // -- for an elaborated-type-specifier of the form 5598 // 5599 // class-key identifier 5600 // 5601 // if the elaborated-type-specifier is used in the 5602 // decl-specifier-seq or parameter-declaration-clause of a 5603 // function defined in namespace scope, the identifier is 5604 // declared as a class-name in the namespace that contains 5605 // the declaration; otherwise, except as a friend 5606 // declaration, the identifier is declared in the smallest 5607 // non-class, non-function-prototype scope that contains the 5608 // declaration. 5609 // 5610 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5611 // C structs and unions. 5612 // 5613 // It is an error in C++ to declare (rather than define) an enum 5614 // type, including via an elaborated type specifier. We'll 5615 // diagnose that later; for now, declare the enum in the same 5616 // scope as we would have picked for any other tag type. 5617 // 5618 // GNU C also supports this behavior as part of its incomplete 5619 // enum types extension, while GNU C++ does not. 5620 // 5621 // Find the context where we'll be declaring the tag. 5622 // FIXME: We would like to maintain the current DeclContext as the 5623 // lexical context, 5624 while (SearchDC->isRecord()) 5625 SearchDC = SearchDC->getParent(); 5626 5627 // Find the scope where we'll be declaring the tag. 5628 while (S->isClassScope() || 5629 (getLangOptions().CPlusPlus && 5630 S->isFunctionPrototypeScope()) || 5631 ((S->getFlags() & Scope::DeclScope) == 0) || 5632 (S->getEntity() && 5633 ((DeclContext *)S->getEntity())->isTransparentContext())) 5634 S = S->getParent(); 5635 } else { 5636 assert(TUK == TUK_Friend); 5637 // C++ [namespace.memdef]p3: 5638 // If a friend declaration in a non-local class first declares a 5639 // class or function, the friend class or function is a member of 5640 // the innermost enclosing namespace. 5641 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5642 } 5643 5644 // In C++, we need to do a redeclaration lookup to properly 5645 // diagnose some problems. 5646 if (getLangOptions().CPlusPlus) { 5647 Previous.setRedeclarationKind(ForRedeclaration); 5648 LookupQualifiedName(Previous, SearchDC); 5649 } 5650 } 5651 5652 if (!Previous.empty()) { 5653 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5654 5655 // It's okay to have a tag decl in the same scope as a typedef 5656 // which hides a tag decl in the same scope. Finding this 5657 // insanity with a redeclaration lookup can only actually happen 5658 // in C++. 5659 // 5660 // This is also okay for elaborated-type-specifiers, which is 5661 // technically forbidden by the current standard but which is 5662 // okay according to the likely resolution of an open issue; 5663 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5664 if (getLangOptions().CPlusPlus) { 5665 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5666 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5667 TagDecl *Tag = TT->getDecl(); 5668 if (Tag->getDeclName() == Name && 5669 Tag->getDeclContext()->getRedeclContext() 5670 ->Equals(TD->getDeclContext()->getRedeclContext())) { 5671 PrevDecl = Tag; 5672 Previous.clear(); 5673 Previous.addDecl(Tag); 5674 Previous.resolveKind(); 5675 } 5676 } 5677 } 5678 } 5679 5680 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5681 // If this is a use of a previous tag, or if the tag is already declared 5682 // in the same scope (so that the definition/declaration completes or 5683 // rementions the tag), reuse the decl. 5684 if (TUK == TUK_Reference || TUK == TUK_Friend || 5685 isDeclInScope(PrevDecl, SearchDC, S)) { 5686 // Make sure that this wasn't declared as an enum and now used as a 5687 // struct or something similar. 5688 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5689 bool SafeToContinue 5690 = (PrevTagDecl->getTagKind() != TTK_Enum && 5691 Kind != TTK_Enum); 5692 if (SafeToContinue) 5693 Diag(KWLoc, diag::err_use_with_wrong_tag) 5694 << Name 5695 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5696 PrevTagDecl->getKindName()); 5697 else 5698 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5699 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5700 5701 if (SafeToContinue) 5702 Kind = PrevTagDecl->getTagKind(); 5703 else { 5704 // Recover by making this an anonymous redefinition. 5705 Name = 0; 5706 Previous.clear(); 5707 Invalid = true; 5708 } 5709 } 5710 5711 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 5712 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 5713 5714 // All conflicts with previous declarations are recovered by 5715 // returning the previous declaration. 5716 if (ScopedEnum != PrevEnum->isScoped()) { 5717 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 5718 << PrevEnum->isScoped(); 5719 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5720 return PrevTagDecl; 5721 } 5722 else if (EnumUnderlying && PrevEnum->isFixed()) { 5723 QualType T; 5724 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5725 T = TI->getType(); 5726 else 5727 T = QualType(EnumUnderlying.get<const Type*>(), 0); 5728 5729 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 5730 Diag(KWLoc, diag::err_enum_redeclare_type_mismatch); 5731 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5732 return PrevTagDecl; 5733 } 5734 } 5735 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 5736 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 5737 << PrevEnum->isFixed(); 5738 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5739 return PrevTagDecl; 5740 } 5741 } 5742 5743 if (!Invalid) { 5744 // If this is a use, just return the declaration we found. 5745 5746 // FIXME: In the future, return a variant or some other clue 5747 // for the consumer of this Decl to know it doesn't own it. 5748 // For our current ASTs this shouldn't be a problem, but will 5749 // need to be changed with DeclGroups. 5750 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5751 TUK == TUK_Friend) 5752 return PrevTagDecl; 5753 5754 // Diagnose attempts to redefine a tag. 5755 if (TUK == TUK_Definition) { 5756 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5757 // If we're defining a specialization and the previous definition 5758 // is from an implicit instantiation, don't emit an error 5759 // here; we'll catch this in the general case below. 5760 if (!isExplicitSpecialization || 5761 !isa<CXXRecordDecl>(Def) || 5762 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5763 == TSK_ExplicitSpecialization) { 5764 Diag(NameLoc, diag::err_redefinition) << Name; 5765 Diag(Def->getLocation(), diag::note_previous_definition); 5766 // If this is a redefinition, recover by making this 5767 // struct be anonymous, which will make any later 5768 // references get the previous definition. 5769 Name = 0; 5770 Previous.clear(); 5771 Invalid = true; 5772 } 5773 } else { 5774 // If the type is currently being defined, complain 5775 // about a nested redefinition. 5776 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5777 if (Tag->isBeingDefined()) { 5778 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5779 Diag(PrevTagDecl->getLocation(), 5780 diag::note_previous_definition); 5781 Name = 0; 5782 Previous.clear(); 5783 Invalid = true; 5784 } 5785 } 5786 5787 // Okay, this is definition of a previously declared or referenced 5788 // tag PrevDecl. We're going to create a new Decl for it. 5789 } 5790 } 5791 // If we get here we have (another) forward declaration or we 5792 // have a definition. Just create a new decl. 5793 5794 } else { 5795 // If we get here, this is a definition of a new tag type in a nested 5796 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5797 // new decl/type. We set PrevDecl to NULL so that the entities 5798 // have distinct types. 5799 Previous.clear(); 5800 } 5801 // If we get here, we're going to create a new Decl. If PrevDecl 5802 // is non-NULL, it's a definition of the tag declared by 5803 // PrevDecl. If it's NULL, we have a new definition. 5804 5805 5806 // Otherwise, PrevDecl is not a tag, but was found with tag 5807 // lookup. This is only actually possible in C++, where a few 5808 // things like templates still live in the tag namespace. 5809 } else { 5810 assert(getLangOptions().CPlusPlus); 5811 5812 // Use a better diagnostic if an elaborated-type-specifier 5813 // found the wrong kind of type on the first 5814 // (non-redeclaration) lookup. 5815 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5816 !Previous.isForRedeclaration()) { 5817 unsigned Kind = 0; 5818 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5819 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5820 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5821 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5822 Invalid = true; 5823 5824 // Otherwise, only diagnose if the declaration is in scope. 5825 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5826 // do nothing 5827 5828 // Diagnose implicit declarations introduced by elaborated types. 5829 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5830 unsigned Kind = 0; 5831 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5832 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5833 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5834 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5835 Invalid = true; 5836 5837 // Otherwise it's a declaration. Call out a particularly common 5838 // case here. 5839 } else if (isa<TypedefDecl>(PrevDecl)) { 5840 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5841 << Name 5842 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5843 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5844 Invalid = true; 5845 5846 // Otherwise, diagnose. 5847 } else { 5848 // The tag name clashes with something else in the target scope, 5849 // issue an error and recover by making this tag be anonymous. 5850 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5851 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5852 Name = 0; 5853 Invalid = true; 5854 } 5855 5856 // The existing declaration isn't relevant to us; we're in a 5857 // new scope, so clear out the previous declaration. 5858 Previous.clear(); 5859 } 5860 } 5861 5862CreateNewDecl: 5863 5864 TagDecl *PrevDecl = 0; 5865 if (Previous.isSingleResult()) 5866 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5867 5868 // If there is an identifier, use the location of the identifier as the 5869 // location of the decl, otherwise use the location of the struct/union 5870 // keyword. 5871 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5872 5873 // Otherwise, create a new declaration. If there is a previous 5874 // declaration of the same entity, the two will be linked via 5875 // PrevDecl. 5876 TagDecl *New; 5877 5878 bool IsForwardReference = false; 5879 if (Kind == TTK_Enum) { 5880 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5881 // enum X { A, B, C } D; D should chain to X. 5882 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5883 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 5884 !EnumUnderlying.isNull()); 5885 // If this is an undefined enum, warn. 5886 if (TUK != TUK_Definition && !Invalid) { 5887 TagDecl *Def; 5888 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 5889 // C++0x: 7.2p2: opaque-enum-declaration. 5890 // Conflicts are diagnosed above. Do nothing. 5891 } 5892 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5893 Diag(Loc, diag::ext_forward_ref_enum_def) 5894 << New; 5895 Diag(Def->getLocation(), diag::note_previous_definition); 5896 } else { 5897 unsigned DiagID = diag::ext_forward_ref_enum; 5898 if (getLangOptions().Microsoft) 5899 DiagID = diag::ext_ms_forward_ref_enum; 5900 else if (getLangOptions().CPlusPlus) 5901 DiagID = diag::err_forward_ref_enum; 5902 Diag(Loc, DiagID); 5903 5904 // If this is a forward-declared reference to an enumeration, make a 5905 // note of it; we won't actually be introducing the declaration into 5906 // the declaration context. 5907 if (TUK == TUK_Reference) 5908 IsForwardReference = true; 5909 } 5910 } 5911 5912 if (EnumUnderlying) { 5913 EnumDecl *ED = cast<EnumDecl>(New); 5914 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5915 ED->setIntegerTypeSourceInfo(TI); 5916 else 5917 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 5918 ED->setPromotionType(ED->getIntegerType()); 5919 } 5920 5921 } else { 5922 // struct/union/class 5923 5924 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5925 // struct X { int A; } D; D should chain to X. 5926 if (getLangOptions().CPlusPlus) { 5927 // FIXME: Look for a way to use RecordDecl for simple structs. 5928 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5929 cast_or_null<CXXRecordDecl>(PrevDecl)); 5930 5931 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5932 StdBadAlloc = cast<CXXRecordDecl>(New); 5933 } else 5934 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5935 cast_or_null<RecordDecl>(PrevDecl)); 5936 } 5937 5938 // Maybe add qualifier info. 5939 if (SS.isNotEmpty()) { 5940 if (SS.isSet()) { 5941 NestedNameSpecifier *NNS 5942 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5943 New->setQualifierInfo(NNS, SS.getRange()); 5944 if (NumMatchedTemplateParamLists > 0) { 5945 New->setTemplateParameterListsInfo(Context, 5946 NumMatchedTemplateParamLists, 5947 (TemplateParameterList**) TemplateParameterLists.release()); 5948 } 5949 } 5950 else 5951 Invalid = true; 5952 } 5953 5954 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5955 // Add alignment attributes if necessary; these attributes are checked when 5956 // the ASTContext lays out the structure. 5957 // 5958 // It is important for implementing the correct semantics that this 5959 // happen here (in act on tag decl). The #pragma pack stack is 5960 // maintained as a result of parser callbacks which can occur at 5961 // many points during the parsing of a struct declaration (because 5962 // the #pragma tokens are effectively skipped over during the 5963 // parsing of the struct). 5964 AddAlignmentAttributesForRecord(RD); 5965 } 5966 5967 // If this is a specialization of a member class (of a class template), 5968 // check the specialization. 5969 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5970 Invalid = true; 5971 5972 if (Invalid) 5973 New->setInvalidDecl(); 5974 5975 if (Attr) 5976 ProcessDeclAttributeList(S, New, Attr); 5977 5978 // If we're declaring or defining a tag in function prototype scope 5979 // in C, note that this type can only be used within the function. 5980 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5981 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5982 5983 // Set the lexical context. If the tag has a C++ scope specifier, the 5984 // lexical context will be different from the semantic context. 5985 New->setLexicalDeclContext(CurContext); 5986 5987 // Mark this as a friend decl if applicable. 5988 if (TUK == TUK_Friend) 5989 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5990 5991 // Set the access specifier. 5992 if (!Invalid && SearchDC->isRecord()) 5993 SetMemberAccessSpecifier(New, PrevDecl, AS); 5994 5995 if (TUK == TUK_Definition) 5996 New->startDefinition(); 5997 5998 // If this has an identifier, add it to the scope stack. 5999 if (TUK == TUK_Friend) { 6000 // We might be replacing an existing declaration in the lookup tables; 6001 // if so, borrow its access specifier. 6002 if (PrevDecl) 6003 New->setAccess(PrevDecl->getAccess()); 6004 6005 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6006 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6007 if (Name) // can be null along some error paths 6008 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6009 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6010 } else if (Name) { 6011 S = getNonFieldDeclScope(S); 6012 PushOnScopeChains(New, S, !IsForwardReference); 6013 if (IsForwardReference) 6014 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6015 6016 } else { 6017 CurContext->addDecl(New); 6018 } 6019 6020 // If this is the C FILE type, notify the AST context. 6021 if (IdentifierInfo *II = New->getIdentifier()) 6022 if (!New->isInvalidDecl() && 6023 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6024 II->isStr("FILE")) 6025 Context.setFILEDecl(New); 6026 6027 OwnedDecl = true; 6028 return New; 6029} 6030 6031void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6032 AdjustDeclIfTemplate(TagD); 6033 TagDecl *Tag = cast<TagDecl>(TagD); 6034 6035 // Enter the tag context. 6036 PushDeclContext(S, Tag); 6037} 6038 6039void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6040 SourceLocation LBraceLoc) { 6041 AdjustDeclIfTemplate(TagD); 6042 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6043 6044 FieldCollector->StartClass(); 6045 6046 if (!Record->getIdentifier()) 6047 return; 6048 6049 // C++ [class]p2: 6050 // [...] The class-name is also inserted into the scope of the 6051 // class itself; this is known as the injected-class-name. For 6052 // purposes of access checking, the injected-class-name is treated 6053 // as if it were a public member name. 6054 CXXRecordDecl *InjectedClassName 6055 = CXXRecordDecl::Create(Context, Record->getTagKind(), 6056 CurContext, Record->getLocation(), 6057 Record->getIdentifier(), 6058 Record->getTagKeywordLoc(), 6059 /*PrevDecl=*/0, 6060 /*DelayTypeCreation=*/true); 6061 Context.getTypeDeclType(InjectedClassName, Record); 6062 InjectedClassName->setImplicit(); 6063 InjectedClassName->setAccess(AS_public); 6064 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6065 InjectedClassName->setDescribedClassTemplate(Template); 6066 PushOnScopeChains(InjectedClassName, S); 6067 assert(InjectedClassName->isInjectedClassName() && 6068 "Broken injected-class-name"); 6069} 6070 6071void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6072 SourceLocation RBraceLoc) { 6073 AdjustDeclIfTemplate(TagD); 6074 TagDecl *Tag = cast<TagDecl>(TagD); 6075 Tag->setRBraceLoc(RBraceLoc); 6076 6077 if (isa<CXXRecordDecl>(Tag)) 6078 FieldCollector->FinishClass(); 6079 6080 // Exit this scope of this tag's definition. 6081 PopDeclContext(); 6082 6083 // Notify the consumer that we've defined a tag. 6084 Consumer.HandleTagDeclDefinition(Tag); 6085} 6086 6087void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6088 AdjustDeclIfTemplate(TagD); 6089 TagDecl *Tag = cast<TagDecl>(TagD); 6090 Tag->setInvalidDecl(); 6091 6092 // We're undoing ActOnTagStartDefinition here, not 6093 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6094 // the FieldCollector. 6095 6096 PopDeclContext(); 6097} 6098 6099// Note that FieldName may be null for anonymous bitfields. 6100bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6101 QualType FieldTy, const Expr *BitWidth, 6102 bool *ZeroWidth) { 6103 // Default to true; that shouldn't confuse checks for emptiness 6104 if (ZeroWidth) 6105 *ZeroWidth = true; 6106 6107 // C99 6.7.2.1p4 - verify the field type. 6108 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6109 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6110 // Handle incomplete types with specific error. 6111 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6112 return true; 6113 if (FieldName) 6114 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6115 << FieldName << FieldTy << BitWidth->getSourceRange(); 6116 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6117 << FieldTy << BitWidth->getSourceRange(); 6118 } 6119 6120 // If the bit-width is type- or value-dependent, don't try to check 6121 // it now. 6122 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6123 return false; 6124 6125 llvm::APSInt Value; 6126 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6127 return true; 6128 6129 if (Value != 0 && ZeroWidth) 6130 *ZeroWidth = false; 6131 6132 // Zero-width bitfield is ok for anonymous field. 6133 if (Value == 0 && FieldName) 6134 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6135 6136 if (Value.isSigned() && Value.isNegative()) { 6137 if (FieldName) 6138 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6139 << FieldName << Value.toString(10); 6140 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6141 << Value.toString(10); 6142 } 6143 6144 if (!FieldTy->isDependentType()) { 6145 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6146 if (Value.getZExtValue() > TypeSize) { 6147 if (!getLangOptions().CPlusPlus) { 6148 if (FieldName) 6149 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6150 << FieldName << (unsigned)Value.getZExtValue() 6151 << (unsigned)TypeSize; 6152 6153 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6154 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6155 } 6156 6157 if (FieldName) 6158 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6159 << FieldName << (unsigned)Value.getZExtValue() 6160 << (unsigned)TypeSize; 6161 else 6162 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6163 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6164 } 6165 } 6166 6167 return false; 6168} 6169 6170/// ActOnField - Each field of a struct/union/class is passed into this in order 6171/// to create a FieldDecl object for it. 6172Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6173 SourceLocation DeclStart, 6174 Declarator &D, ExprTy *BitfieldWidth) { 6175 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6176 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6177 AS_public); 6178 return Res; 6179} 6180 6181/// HandleField - Analyze a field of a C struct or a C++ data member. 6182/// 6183FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6184 SourceLocation DeclStart, 6185 Declarator &D, Expr *BitWidth, 6186 AccessSpecifier AS) { 6187 IdentifierInfo *II = D.getIdentifier(); 6188 SourceLocation Loc = DeclStart; 6189 if (II) Loc = D.getIdentifierLoc(); 6190 6191 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6192 QualType T = TInfo->getType(); 6193 if (getLangOptions().CPlusPlus) 6194 CheckExtraCXXDefaultArguments(D); 6195 6196 DiagnoseFunctionSpecifiers(D); 6197 6198 if (D.getDeclSpec().isThreadSpecified()) 6199 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6200 6201 // Check to see if this name was declared as a member previously 6202 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6203 LookupName(Previous, S); 6204 assert((Previous.empty() || Previous.isOverloadedResult() || 6205 Previous.isSingleResult()) 6206 && "Lookup of member name should be either overloaded, single or null"); 6207 6208 // If the name is overloaded then get any declaration else get the single result 6209 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6210 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6211 6212 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6213 // Maybe we will complain about the shadowed template parameter. 6214 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6215 // Just pretend that we didn't see the previous declaration. 6216 PrevDecl = 0; 6217 } 6218 6219 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6220 PrevDecl = 0; 6221 6222 bool Mutable 6223 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6224 SourceLocation TSSL = D.getSourceRange().getBegin(); 6225 FieldDecl *NewFD 6226 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6227 AS, PrevDecl, &D); 6228 6229 if (NewFD->isInvalidDecl()) 6230 Record->setInvalidDecl(); 6231 6232 if (NewFD->isInvalidDecl() && PrevDecl) { 6233 // Don't introduce NewFD into scope; there's already something 6234 // with the same name in the same scope. 6235 } else if (II) { 6236 PushOnScopeChains(NewFD, S); 6237 } else 6238 Record->addDecl(NewFD); 6239 6240 return NewFD; 6241} 6242 6243/// \brief Build a new FieldDecl and check its well-formedness. 6244/// 6245/// This routine builds a new FieldDecl given the fields name, type, 6246/// record, etc. \p PrevDecl should refer to any previous declaration 6247/// with the same name and in the same scope as the field to be 6248/// created. 6249/// 6250/// \returns a new FieldDecl. 6251/// 6252/// \todo The Declarator argument is a hack. It will be removed once 6253FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6254 TypeSourceInfo *TInfo, 6255 RecordDecl *Record, SourceLocation Loc, 6256 bool Mutable, Expr *BitWidth, 6257 SourceLocation TSSL, 6258 AccessSpecifier AS, NamedDecl *PrevDecl, 6259 Declarator *D) { 6260 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6261 bool InvalidDecl = false; 6262 if (D) InvalidDecl = D->isInvalidType(); 6263 6264 // If we receive a broken type, recover by assuming 'int' and 6265 // marking this declaration as invalid. 6266 if (T.isNull()) { 6267 InvalidDecl = true; 6268 T = Context.IntTy; 6269 } 6270 6271 QualType EltTy = Context.getBaseElementType(T); 6272 if (!EltTy->isDependentType() && 6273 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6274 // Fields of incomplete type force their record to be invalid. 6275 Record->setInvalidDecl(); 6276 InvalidDecl = true; 6277 } 6278 6279 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6280 // than a variably modified type. 6281 if (!InvalidDecl && T->isVariablyModifiedType()) { 6282 bool SizeIsNegative; 6283 llvm::APSInt Oversized; 6284 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6285 SizeIsNegative, 6286 Oversized); 6287 if (!FixedTy.isNull()) { 6288 Diag(Loc, diag::warn_illegal_constant_array_size); 6289 T = FixedTy; 6290 } else { 6291 if (SizeIsNegative) 6292 Diag(Loc, diag::err_typecheck_negative_array_size); 6293 else if (Oversized.getBoolValue()) 6294 Diag(Loc, diag::err_array_too_large) 6295 << Oversized.toString(10); 6296 else 6297 Diag(Loc, diag::err_typecheck_field_variable_size); 6298 InvalidDecl = true; 6299 } 6300 } 6301 6302 // Fields can not have abstract class types 6303 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6304 diag::err_abstract_type_in_decl, 6305 AbstractFieldType)) 6306 InvalidDecl = true; 6307 6308 bool ZeroWidth = false; 6309 // If this is declared as a bit-field, check the bit-field. 6310 if (!InvalidDecl && BitWidth && 6311 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6312 InvalidDecl = true; 6313 BitWidth = 0; 6314 ZeroWidth = false; 6315 } 6316 6317 // Check that 'mutable' is consistent with the type of the declaration. 6318 if (!InvalidDecl && Mutable) { 6319 unsigned DiagID = 0; 6320 if (T->isReferenceType()) 6321 DiagID = diag::err_mutable_reference; 6322 else if (T.isConstQualified()) 6323 DiagID = diag::err_mutable_const; 6324 6325 if (DiagID) { 6326 SourceLocation ErrLoc = Loc; 6327 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6328 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6329 Diag(ErrLoc, DiagID); 6330 Mutable = false; 6331 InvalidDecl = true; 6332 } 6333 } 6334 6335 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6336 BitWidth, Mutable); 6337 if (InvalidDecl) 6338 NewFD->setInvalidDecl(); 6339 6340 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6341 Diag(Loc, diag::err_duplicate_member) << II; 6342 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6343 NewFD->setInvalidDecl(); 6344 } 6345 6346 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6347 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6348 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6349 if (RDecl->getDefinition()) { 6350 // C++ 9.5p1: An object of a class with a non-trivial 6351 // constructor, a non-trivial copy constructor, a non-trivial 6352 // destructor, or a non-trivial copy assignment operator 6353 // cannot be a member of a union, nor can an array of such 6354 // objects. 6355 // TODO: C++0x alters this restriction significantly. 6356 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6357 NewFD->setInvalidDecl(); 6358 } 6359 } 6360 } 6361 6362 // FIXME: We need to pass in the attributes given an AST 6363 // representation, not a parser representation. 6364 if (D) 6365 // FIXME: What to pass instead of TUScope? 6366 ProcessDeclAttributes(TUScope, NewFD, *D); 6367 6368 if (T.isObjCGCWeak()) 6369 Diag(Loc, diag::warn_attribute_weak_on_field); 6370 6371 NewFD->setAccess(AS); 6372 return NewFD; 6373} 6374 6375bool Sema::CheckNontrivialField(FieldDecl *FD) { 6376 assert(FD); 6377 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6378 6379 if (FD->isInvalidDecl()) 6380 return true; 6381 6382 QualType EltTy = Context.getBaseElementType(FD->getType()); 6383 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6384 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6385 if (RDecl->getDefinition()) { 6386 // We check for copy constructors before constructors 6387 // because otherwise we'll never get complaints about 6388 // copy constructors. 6389 6390 CXXSpecialMember member = CXXInvalid; 6391 if (!RDecl->hasTrivialCopyConstructor()) 6392 member = CXXCopyConstructor; 6393 else if (!RDecl->hasTrivialConstructor()) 6394 member = CXXConstructor; 6395 else if (!RDecl->hasTrivialCopyAssignment()) 6396 member = CXXCopyAssignment; 6397 else if (!RDecl->hasTrivialDestructor()) 6398 member = CXXDestructor; 6399 6400 if (member != CXXInvalid) { 6401 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6402 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6403 DiagnoseNontrivial(RT, member); 6404 return true; 6405 } 6406 } 6407 } 6408 6409 return false; 6410} 6411 6412/// DiagnoseNontrivial - Given that a class has a non-trivial 6413/// special member, figure out why. 6414void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6415 QualType QT(T, 0U); 6416 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6417 6418 // Check whether the member was user-declared. 6419 switch (member) { 6420 case CXXInvalid: 6421 break; 6422 6423 case CXXConstructor: 6424 if (RD->hasUserDeclaredConstructor()) { 6425 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6426 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6427 const FunctionDecl *body = 0; 6428 ci->hasBody(body); 6429 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6430 SourceLocation CtorLoc = ci->getLocation(); 6431 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6432 return; 6433 } 6434 } 6435 6436 assert(0 && "found no user-declared constructors"); 6437 return; 6438 } 6439 break; 6440 6441 case CXXCopyConstructor: 6442 if (RD->hasUserDeclaredCopyConstructor()) { 6443 SourceLocation CtorLoc = 6444 RD->getCopyConstructor(Context, 0)->getLocation(); 6445 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6446 return; 6447 } 6448 break; 6449 6450 case CXXCopyAssignment: 6451 if (RD->hasUserDeclaredCopyAssignment()) { 6452 // FIXME: this should use the location of the copy 6453 // assignment, not the type. 6454 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6455 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6456 return; 6457 } 6458 break; 6459 6460 case CXXDestructor: 6461 if (RD->hasUserDeclaredDestructor()) { 6462 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6463 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6464 return; 6465 } 6466 break; 6467 } 6468 6469 typedef CXXRecordDecl::base_class_iterator base_iter; 6470 6471 // Virtual bases and members inhibit trivial copying/construction, 6472 // but not trivial destruction. 6473 if (member != CXXDestructor) { 6474 // Check for virtual bases. vbases includes indirect virtual bases, 6475 // so we just iterate through the direct bases. 6476 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6477 if (bi->isVirtual()) { 6478 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6479 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6480 return; 6481 } 6482 6483 // Check for virtual methods. 6484 typedef CXXRecordDecl::method_iterator meth_iter; 6485 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6486 ++mi) { 6487 if (mi->isVirtual()) { 6488 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6489 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6490 return; 6491 } 6492 } 6493 } 6494 6495 bool (CXXRecordDecl::*hasTrivial)() const; 6496 switch (member) { 6497 case CXXConstructor: 6498 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6499 case CXXCopyConstructor: 6500 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6501 case CXXCopyAssignment: 6502 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6503 case CXXDestructor: 6504 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6505 default: 6506 assert(0 && "unexpected special member"); return; 6507 } 6508 6509 // Check for nontrivial bases (and recurse). 6510 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6511 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6512 assert(BaseRT && "Don't know how to handle dependent bases"); 6513 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6514 if (!(BaseRecTy->*hasTrivial)()) { 6515 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6516 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6517 DiagnoseNontrivial(BaseRT, member); 6518 return; 6519 } 6520 } 6521 6522 // Check for nontrivial members (and recurse). 6523 typedef RecordDecl::field_iterator field_iter; 6524 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6525 ++fi) { 6526 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6527 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6528 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6529 6530 if (!(EltRD->*hasTrivial)()) { 6531 SourceLocation FLoc = (*fi)->getLocation(); 6532 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6533 DiagnoseNontrivial(EltRT, member); 6534 return; 6535 } 6536 } 6537 } 6538 6539 assert(0 && "found no explanation for non-trivial member"); 6540} 6541 6542/// TranslateIvarVisibility - Translate visibility from a token ID to an 6543/// AST enum value. 6544static ObjCIvarDecl::AccessControl 6545TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6546 switch (ivarVisibility) { 6547 default: assert(0 && "Unknown visitibility kind"); 6548 case tok::objc_private: return ObjCIvarDecl::Private; 6549 case tok::objc_public: return ObjCIvarDecl::Public; 6550 case tok::objc_protected: return ObjCIvarDecl::Protected; 6551 case tok::objc_package: return ObjCIvarDecl::Package; 6552 } 6553} 6554 6555/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6556/// in order to create an IvarDecl object for it. 6557Decl *Sema::ActOnIvar(Scope *S, 6558 SourceLocation DeclStart, 6559 Decl *IntfDecl, 6560 Declarator &D, ExprTy *BitfieldWidth, 6561 tok::ObjCKeywordKind Visibility) { 6562 6563 IdentifierInfo *II = D.getIdentifier(); 6564 Expr *BitWidth = (Expr*)BitfieldWidth; 6565 SourceLocation Loc = DeclStart; 6566 if (II) Loc = D.getIdentifierLoc(); 6567 6568 // FIXME: Unnamed fields can be handled in various different ways, for 6569 // example, unnamed unions inject all members into the struct namespace! 6570 6571 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6572 QualType T = TInfo->getType(); 6573 6574 if (BitWidth) { 6575 // 6.7.2.1p3, 6.7.2.1p4 6576 if (VerifyBitField(Loc, II, T, BitWidth)) { 6577 D.setInvalidType(); 6578 BitWidth = 0; 6579 } 6580 } else { 6581 // Not a bitfield. 6582 6583 // validate II. 6584 6585 } 6586 if (T->isReferenceType()) { 6587 Diag(Loc, diag::err_ivar_reference_type); 6588 D.setInvalidType(); 6589 } 6590 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6591 // than a variably modified type. 6592 else if (T->isVariablyModifiedType()) { 6593 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6594 D.setInvalidType(); 6595 } 6596 6597 // Get the visibility (access control) for this ivar. 6598 ObjCIvarDecl::AccessControl ac = 6599 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6600 : ObjCIvarDecl::None; 6601 // Must set ivar's DeclContext to its enclosing interface. 6602 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6603 ObjCContainerDecl *EnclosingContext; 6604 if (ObjCImplementationDecl *IMPDecl = 6605 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6606 if (!LangOpts.ObjCNonFragileABI2) { 6607 // Case of ivar declared in an implementation. Context is that of its class. 6608 EnclosingContext = IMPDecl->getClassInterface(); 6609 assert(EnclosingContext && "Implementation has no class interface!"); 6610 } 6611 else 6612 EnclosingContext = EnclosingDecl; 6613 } else { 6614 if (ObjCCategoryDecl *CDecl = 6615 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6616 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6617 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6618 return 0; 6619 } 6620 } 6621 EnclosingContext = EnclosingDecl; 6622 } 6623 6624 // Construct the decl. 6625 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6626 EnclosingContext, Loc, II, T, 6627 TInfo, ac, (Expr *)BitfieldWidth); 6628 6629 if (II) { 6630 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6631 ForRedeclaration); 6632 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6633 && !isa<TagDecl>(PrevDecl)) { 6634 Diag(Loc, diag::err_duplicate_member) << II; 6635 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6636 NewID->setInvalidDecl(); 6637 } 6638 } 6639 6640 // Process attributes attached to the ivar. 6641 ProcessDeclAttributes(S, NewID, D); 6642 6643 if (D.isInvalidType()) 6644 NewID->setInvalidDecl(); 6645 6646 if (II) { 6647 // FIXME: When interfaces are DeclContexts, we'll need to add 6648 // these to the interface. 6649 S->AddDecl(NewID); 6650 IdResolver.AddDecl(NewID); 6651 } 6652 6653 return NewID; 6654} 6655 6656/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6657/// class and class extensions. For every class @interface and class 6658/// extension @interface, if the last ivar is a bitfield of any type, 6659/// then add an implicit `char :0` ivar to the end of that interface. 6660void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6661 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6662 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6663 return; 6664 6665 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6666 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6667 6668 if (!Ivar->isBitField()) 6669 return; 6670 uint64_t BitFieldSize = 6671 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6672 if (BitFieldSize == 0) 6673 return; 6674 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6675 if (!ID) { 6676 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6677 if (!CD->IsClassExtension()) 6678 return; 6679 } 6680 // No need to add this to end of @implementation. 6681 else 6682 return; 6683 } 6684 // All conditions are met. Add a new bitfield to the tail end of ivars. 6685 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6686 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 6687 6688 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6689 DeclLoc, 0, 6690 Context.CharTy, 6691 Context.CreateTypeSourceInfo(Context.CharTy), 6692 ObjCIvarDecl::Private, BW, 6693 true); 6694 AllIvarDecls.push_back(Ivar); 6695} 6696 6697void Sema::ActOnFields(Scope* S, 6698 SourceLocation RecLoc, Decl *EnclosingDecl, 6699 Decl **Fields, unsigned NumFields, 6700 SourceLocation LBrac, SourceLocation RBrac, 6701 AttributeList *Attr) { 6702 assert(EnclosingDecl && "missing record or interface decl"); 6703 6704 // If the decl this is being inserted into is invalid, then it may be a 6705 // redeclaration or some other bogus case. Don't try to add fields to it. 6706 if (EnclosingDecl->isInvalidDecl()) { 6707 // FIXME: Deallocate fields? 6708 return; 6709 } 6710 6711 6712 // Verify that all the fields are okay. 6713 unsigned NumNamedMembers = 0; 6714 llvm::SmallVector<FieldDecl*, 32> RecFields; 6715 6716 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6717 for (unsigned i = 0; i != NumFields; ++i) { 6718 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6719 6720 // Get the type for the field. 6721 Type *FDTy = FD->getType().getTypePtr(); 6722 6723 if (!FD->isAnonymousStructOrUnion()) { 6724 // Remember all fields written by the user. 6725 RecFields.push_back(FD); 6726 } 6727 6728 // If the field is already invalid for some reason, don't emit more 6729 // diagnostics about it. 6730 if (FD->isInvalidDecl()) { 6731 EnclosingDecl->setInvalidDecl(); 6732 continue; 6733 } 6734 6735 // C99 6.7.2.1p2: 6736 // A structure or union shall not contain a member with 6737 // incomplete or function type (hence, a structure shall not 6738 // contain an instance of itself, but may contain a pointer to 6739 // an instance of itself), except that the last member of a 6740 // structure with more than one named member may have incomplete 6741 // array type; such a structure (and any union containing, 6742 // possibly recursively, a member that is such a structure) 6743 // shall not be a member of a structure or an element of an 6744 // array. 6745 if (FDTy->isFunctionType()) { 6746 // Field declared as a function. 6747 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6748 << FD->getDeclName(); 6749 FD->setInvalidDecl(); 6750 EnclosingDecl->setInvalidDecl(); 6751 continue; 6752 } else if (FDTy->isIncompleteArrayType() && Record && 6753 ((i == NumFields - 1 && !Record->isUnion()) || 6754 (getLangOptions().Microsoft && 6755 (i == NumFields - 1 || Record->isUnion())))) { 6756 // Flexible array member. 6757 // Microsoft is more permissive regarding flexible array. 6758 // It will accept flexible array in union and also 6759 // as the sole element of a struct/class. 6760 if (getLangOptions().Microsoft) { 6761 if (Record->isUnion()) 6762 Diag(FD->getLocation(), diag::ext_flexible_array_union) 6763 << FD->getDeclName(); 6764 else if (NumFields == 1) 6765 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 6766 << FD->getDeclName() << Record->getTagKind(); 6767 } else if (NumNamedMembers < 1) { 6768 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6769 << FD->getDeclName(); 6770 FD->setInvalidDecl(); 6771 EnclosingDecl->setInvalidDecl(); 6772 continue; 6773 } 6774 if (!FD->getType()->isDependentType() && 6775 !Context.getBaseElementType(FD->getType())->isPODType()) { 6776 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6777 << FD->getDeclName() << FD->getType(); 6778 FD->setInvalidDecl(); 6779 EnclosingDecl->setInvalidDecl(); 6780 continue; 6781 } 6782 // Okay, we have a legal flexible array member at the end of the struct. 6783 if (Record) 6784 Record->setHasFlexibleArrayMember(true); 6785 } else if (!FDTy->isDependentType() && 6786 RequireCompleteType(FD->getLocation(), FD->getType(), 6787 diag::err_field_incomplete)) { 6788 // Incomplete type 6789 FD->setInvalidDecl(); 6790 EnclosingDecl->setInvalidDecl(); 6791 continue; 6792 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6793 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6794 // If this is a member of a union, then entire union becomes "flexible". 6795 if (Record && Record->isUnion()) { 6796 Record->setHasFlexibleArrayMember(true); 6797 } else { 6798 // If this is a struct/class and this is not the last element, reject 6799 // it. Note that GCC supports variable sized arrays in the middle of 6800 // structures. 6801 if (i != NumFields-1) 6802 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6803 << FD->getDeclName() << FD->getType(); 6804 else { 6805 // We support flexible arrays at the end of structs in 6806 // other structs as an extension. 6807 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6808 << FD->getDeclName(); 6809 if (Record) 6810 Record->setHasFlexibleArrayMember(true); 6811 } 6812 } 6813 } 6814 if (Record && FDTTy->getDecl()->hasObjectMember()) 6815 Record->setHasObjectMember(true); 6816 } else if (FDTy->isObjCObjectType()) { 6817 /// A field cannot be an Objective-c object 6818 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6819 FD->setInvalidDecl(); 6820 EnclosingDecl->setInvalidDecl(); 6821 continue; 6822 } else if (getLangOptions().ObjC1 && 6823 getLangOptions().getGCMode() != LangOptions::NonGC && 6824 Record && 6825 (FD->getType()->isObjCObjectPointerType() || 6826 FD->getType().isObjCGCStrong())) 6827 Record->setHasObjectMember(true); 6828 else if (Context.getAsArrayType(FD->getType())) { 6829 QualType BaseType = Context.getBaseElementType(FD->getType()); 6830 if (Record && BaseType->isRecordType() && 6831 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6832 Record->setHasObjectMember(true); 6833 } 6834 // Keep track of the number of named members. 6835 if (FD->getIdentifier()) 6836 ++NumNamedMembers; 6837 } 6838 6839 // Okay, we successfully defined 'Record'. 6840 if (Record) { 6841 bool Completed = false; 6842 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 6843 if (!CXXRecord->isInvalidDecl()) { 6844 // Set access bits correctly on the directly-declared conversions. 6845 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 6846 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 6847 I != E; ++I) 6848 Convs->setAccess(I, (*I)->getAccess()); 6849 6850 if (!CXXRecord->isDependentType()) { 6851 // Add any implicitly-declared members to this class. 6852 AddImplicitlyDeclaredMembersToClass(CXXRecord); 6853 6854 // If we have virtual base classes, we may end up finding multiple 6855 // final overriders for a given virtual function. Check for this 6856 // problem now. 6857 if (CXXRecord->getNumVBases()) { 6858 CXXFinalOverriderMap FinalOverriders; 6859 CXXRecord->getFinalOverriders(FinalOverriders); 6860 6861 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 6862 MEnd = FinalOverriders.end(); 6863 M != MEnd; ++M) { 6864 for (OverridingMethods::iterator SO = M->second.begin(), 6865 SOEnd = M->second.end(); 6866 SO != SOEnd; ++SO) { 6867 assert(SO->second.size() > 0 && 6868 "Virtual function without overridding functions?"); 6869 if (SO->second.size() == 1) 6870 continue; 6871 6872 // C++ [class.virtual]p2: 6873 // In a derived class, if a virtual member function of a base 6874 // class subobject has more than one final overrider the 6875 // program is ill-formed. 6876 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 6877 << (NamedDecl *)M->first << Record; 6878 Diag(M->first->getLocation(), 6879 diag::note_overridden_virtual_function); 6880 for (OverridingMethods::overriding_iterator 6881 OM = SO->second.begin(), 6882 OMEnd = SO->second.end(); 6883 OM != OMEnd; ++OM) 6884 Diag(OM->Method->getLocation(), diag::note_final_overrider) 6885 << (NamedDecl *)M->first << OM->Method->getParent(); 6886 6887 Record->setInvalidDecl(); 6888 } 6889 } 6890 CXXRecord->completeDefinition(&FinalOverriders); 6891 Completed = true; 6892 } 6893 } 6894 } 6895 } 6896 6897 if (!Completed) 6898 Record->completeDefinition(); 6899 } else { 6900 ObjCIvarDecl **ClsFields = 6901 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6902 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6903 ID->setLocEnd(RBrac); 6904 // Add ivar's to class's DeclContext. 6905 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6906 ClsFields[i]->setLexicalDeclContext(ID); 6907 ID->addDecl(ClsFields[i]); 6908 } 6909 // Must enforce the rule that ivars in the base classes may not be 6910 // duplicates. 6911 if (ID->getSuperClass()) 6912 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6913 } else if (ObjCImplementationDecl *IMPDecl = 6914 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6915 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6916 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6917 // Ivar declared in @implementation never belongs to the implementation. 6918 // Only it is in implementation's lexical context. 6919 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6920 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6921 } else if (ObjCCategoryDecl *CDecl = 6922 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6923 // case of ivars in class extension; all other cases have been 6924 // reported as errors elsewhere. 6925 // FIXME. Class extension does not have a LocEnd field. 6926 // CDecl->setLocEnd(RBrac); 6927 // Add ivar's to class extension's DeclContext. 6928 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6929 ClsFields[i]->setLexicalDeclContext(CDecl); 6930 CDecl->addDecl(ClsFields[i]); 6931 } 6932 } 6933 } 6934 6935 if (Attr) 6936 ProcessDeclAttributeList(S, Record, Attr); 6937 6938 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6939 // set the visibility of this record. 6940 if (Record && !Record->getDeclContext()->isRecord()) 6941 AddPushedVisibilityAttribute(Record); 6942} 6943 6944/// \brief Determine whether the given integral value is representable within 6945/// the given type T. 6946static bool isRepresentableIntegerValue(ASTContext &Context, 6947 llvm::APSInt &Value, 6948 QualType T) { 6949 assert(T->isIntegralType(Context) && "Integral type required!"); 6950 unsigned BitWidth = Context.getIntWidth(T); 6951 6952 if (Value.isUnsigned() || Value.isNonNegative()) { 6953 if (T->isSignedIntegerType()) 6954 --BitWidth; 6955 return Value.getActiveBits() <= BitWidth; 6956 } 6957 return Value.getMinSignedBits() <= BitWidth; 6958} 6959 6960// \brief Given an integral type, return the next larger integral type 6961// (or a NULL type of no such type exists). 6962static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6963 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6964 // enum checking below. 6965 assert(T->isIntegralType(Context) && "Integral type required!"); 6966 const unsigned NumTypes = 4; 6967 QualType SignedIntegralTypes[NumTypes] = { 6968 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6969 }; 6970 QualType UnsignedIntegralTypes[NumTypes] = { 6971 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6972 Context.UnsignedLongLongTy 6973 }; 6974 6975 unsigned BitWidth = Context.getTypeSize(T); 6976 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6977 : UnsignedIntegralTypes; 6978 for (unsigned I = 0; I != NumTypes; ++I) 6979 if (Context.getTypeSize(Types[I]) > BitWidth) 6980 return Types[I]; 6981 6982 return QualType(); 6983} 6984 6985EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6986 EnumConstantDecl *LastEnumConst, 6987 SourceLocation IdLoc, 6988 IdentifierInfo *Id, 6989 Expr *Val) { 6990 unsigned IntWidth = Context.Target.getIntWidth(); 6991 llvm::APSInt EnumVal(IntWidth); 6992 QualType EltTy; 6993 if (Val) { 6994 if (Enum->isDependentType() || Val->isTypeDependent()) 6995 EltTy = Context.DependentTy; 6996 else { 6997 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6998 SourceLocation ExpLoc; 6999 if (!Val->isValueDependent() && 7000 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7001 Val = 0; 7002 } else { 7003 if (!getLangOptions().CPlusPlus) { 7004 // C99 6.7.2.2p2: 7005 // The expression that defines the value of an enumeration constant 7006 // shall be an integer constant expression that has a value 7007 // representable as an int. 7008 7009 // Complain if the value is not representable in an int. 7010 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7011 Diag(IdLoc, diag::ext_enum_value_not_int) 7012 << EnumVal.toString(10) << Val->getSourceRange() 7013 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7014 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7015 // Force the type of the expression to 'int'. 7016 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 7017 } 7018 } 7019 7020 if (Enum->isFixed()) { 7021 EltTy = Enum->getIntegerType(); 7022 7023 // C++0x [dcl.enum]p5: 7024 // ... if the initializing value of an enumerator cannot be 7025 // represented by the underlying type, the program is ill-formed. 7026 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) 7027 Diag(IdLoc, diag::err_enumerator_too_large) 7028 << EltTy; 7029 else 7030 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7031 } 7032 else { 7033 // C++0x [dcl.enum]p5: 7034 // If the underlying type is not fixed, the type of each enumerator 7035 // is the type of its initializing value: 7036 // - If an initializer is specified for an enumerator, the 7037 // initializing value has the same type as the expression. 7038 EltTy = Val->getType(); 7039 } 7040 } 7041 } 7042 } 7043 7044 if (!Val) { 7045 if (Enum->isDependentType()) 7046 EltTy = Context.DependentTy; 7047 else if (!LastEnumConst) { 7048 // C++0x [dcl.enum]p5: 7049 // If the underlying type is not fixed, the type of each enumerator 7050 // is the type of its initializing value: 7051 // - If no initializer is specified for the first enumerator, the 7052 // initializing value has an unspecified integral type. 7053 // 7054 // GCC uses 'int' for its unspecified integral type, as does 7055 // C99 6.7.2.2p3. 7056 if (Enum->isFixed()) { 7057 EltTy = Enum->getIntegerType(); 7058 } 7059 else { 7060 EltTy = Context.IntTy; 7061 } 7062 } else { 7063 // Assign the last value + 1. 7064 EnumVal = LastEnumConst->getInitVal(); 7065 ++EnumVal; 7066 EltTy = LastEnumConst->getType(); 7067 7068 // Check for overflow on increment. 7069 if (EnumVal < LastEnumConst->getInitVal()) { 7070 // C++0x [dcl.enum]p5: 7071 // If the underlying type is not fixed, the type of each enumerator 7072 // is the type of its initializing value: 7073 // 7074 // - Otherwise the type of the initializing value is the same as 7075 // the type of the initializing value of the preceding enumerator 7076 // unless the incremented value is not representable in that type, 7077 // in which case the type is an unspecified integral type 7078 // sufficient to contain the incremented value. If no such type 7079 // exists, the program is ill-formed. 7080 QualType T = getNextLargerIntegralType(Context, EltTy); 7081 if (T.isNull() || Enum->isFixed()) { 7082 // There is no integral type larger enough to represent this 7083 // value. Complain, then allow the value to wrap around. 7084 EnumVal = LastEnumConst->getInitVal(); 7085 EnumVal.zext(EnumVal.getBitWidth() * 2); 7086 ++EnumVal; 7087 if (Enum->isFixed()) 7088 // When the underlying type is fixed, this is ill-formed. 7089 Diag(IdLoc, diag::err_enumerator_wrapped) 7090 << EnumVal.toString(10) 7091 << EltTy; 7092 else 7093 Diag(IdLoc, diag::warn_enumerator_too_large) 7094 << EnumVal.toString(10); 7095 } else { 7096 EltTy = T; 7097 } 7098 7099 // Retrieve the last enumerator's value, extent that type to the 7100 // type that is supposed to be large enough to represent the incremented 7101 // value, then increment. 7102 EnumVal = LastEnumConst->getInitVal(); 7103 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7104 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7105 ++EnumVal; 7106 7107 // If we're not in C++, diagnose the overflow of enumerator values, 7108 // which in C99 means that the enumerator value is not representable in 7109 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7110 // permits enumerator values that are representable in some larger 7111 // integral type. 7112 if (!getLangOptions().CPlusPlus && !T.isNull()) 7113 Diag(IdLoc, diag::warn_enum_value_overflow); 7114 } else if (!getLangOptions().CPlusPlus && 7115 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7116 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7117 Diag(IdLoc, diag::ext_enum_value_not_int) 7118 << EnumVal.toString(10) << 1; 7119 } 7120 } 7121 } 7122 7123 if (!EltTy->isDependentType()) { 7124 // Make the enumerator value match the signedness and size of the 7125 // enumerator's type. 7126 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7127 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7128 } 7129 7130 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7131 Val, EnumVal); 7132} 7133 7134 7135Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 7136 Decl *lastEnumConst, 7137 SourceLocation IdLoc, 7138 IdentifierInfo *Id, 7139 SourceLocation EqualLoc, ExprTy *val) { 7140 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7141 EnumConstantDecl *LastEnumConst = 7142 cast_or_null<EnumConstantDecl>(lastEnumConst); 7143 Expr *Val = static_cast<Expr*>(val); 7144 7145 // The scope passed in may not be a decl scope. Zip up the scope tree until 7146 // we find one that is. 7147 S = getNonFieldDeclScope(S); 7148 7149 // Verify that there isn't already something declared with this name in this 7150 // scope. 7151 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7152 ForRedeclaration); 7153 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7154 // Maybe we will complain about the shadowed template parameter. 7155 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7156 // Just pretend that we didn't see the previous declaration. 7157 PrevDecl = 0; 7158 } 7159 7160 if (PrevDecl) { 7161 // When in C++, we may get a TagDecl with the same name; in this case the 7162 // enum constant will 'hide' the tag. 7163 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7164 "Received TagDecl when not in C++!"); 7165 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7166 if (isa<EnumConstantDecl>(PrevDecl)) 7167 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7168 else 7169 Diag(IdLoc, diag::err_redefinition) << Id; 7170 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7171 return 0; 7172 } 7173 } 7174 7175 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 7176 IdLoc, Id, Val); 7177 7178 // Register this decl in the current scope stack. 7179 if (New) { 7180 New->setAccess(TheEnumDecl->getAccess()); 7181 PushOnScopeChains(New, S); 7182 } 7183 7184 return New; 7185} 7186 7187void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7188 SourceLocation RBraceLoc, Decl *EnumDeclX, 7189 Decl **Elements, unsigned NumElements, 7190 Scope *S, AttributeList *Attr) { 7191 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7192 QualType EnumType = Context.getTypeDeclType(Enum); 7193 7194 if (Attr) 7195 ProcessDeclAttributeList(S, Enum, Attr); 7196 7197 if (Enum->isDependentType()) { 7198 for (unsigned i = 0; i != NumElements; ++i) { 7199 EnumConstantDecl *ECD = 7200 cast_or_null<EnumConstantDecl>(Elements[i]); 7201 if (!ECD) continue; 7202 7203 ECD->setType(EnumType); 7204 } 7205 7206 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7207 return; 7208 } 7209 7210 // TODO: If the result value doesn't fit in an int, it must be a long or long 7211 // long value. ISO C does not support this, but GCC does as an extension, 7212 // emit a warning. 7213 unsigned IntWidth = Context.Target.getIntWidth(); 7214 unsigned CharWidth = Context.Target.getCharWidth(); 7215 unsigned ShortWidth = Context.Target.getShortWidth(); 7216 7217 // Verify that all the values are okay, compute the size of the values, and 7218 // reverse the list. 7219 unsigned NumNegativeBits = 0; 7220 unsigned NumPositiveBits = 0; 7221 7222 // Keep track of whether all elements have type int. 7223 bool AllElementsInt = true; 7224 7225 for (unsigned i = 0; i != NumElements; ++i) { 7226 EnumConstantDecl *ECD = 7227 cast_or_null<EnumConstantDecl>(Elements[i]); 7228 if (!ECD) continue; // Already issued a diagnostic. 7229 7230 const llvm::APSInt &InitVal = ECD->getInitVal(); 7231 7232 // Keep track of the size of positive and negative values. 7233 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7234 NumPositiveBits = std::max(NumPositiveBits, 7235 (unsigned)InitVal.getActiveBits()); 7236 else 7237 NumNegativeBits = std::max(NumNegativeBits, 7238 (unsigned)InitVal.getMinSignedBits()); 7239 7240 // Keep track of whether every enum element has type int (very commmon). 7241 if (AllElementsInt) 7242 AllElementsInt = ECD->getType() == Context.IntTy; 7243 } 7244 7245 // Figure out the type that should be used for this enum. 7246 // FIXME: Support -fshort-enums. 7247 QualType BestType; 7248 unsigned BestWidth; 7249 7250 // C++0x N3000 [conv.prom]p3: 7251 // An rvalue of an unscoped enumeration type whose underlying 7252 // type is not fixed can be converted to an rvalue of the first 7253 // of the following types that can represent all the values of 7254 // the enumeration: int, unsigned int, long int, unsigned long 7255 // int, long long int, or unsigned long long int. 7256 // C99 6.4.4.3p2: 7257 // An identifier declared as an enumeration constant has type int. 7258 // The C99 rule is modified by a gcc extension 7259 QualType BestPromotionType; 7260 7261 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7262 // -fshort-enums is the equivalent to specifying the packed attribute on all 7263 // enum definitions. 7264 if (LangOpts.ShortEnums) 7265 Packed = true; 7266 7267 if (Enum->isFixed()) { 7268 BestType = BestPromotionType = Enum->getIntegerType(); 7269 // We don't need to set BestWidth, because BestType is going to be the type 7270 // of the enumerators, but we do anyway because otherwise some compilers 7271 // warn that it might be used uninitialized. 7272 BestWidth = CharWidth; 7273 } 7274 else if (NumNegativeBits) { 7275 // If there is a negative value, figure out the smallest integer type (of 7276 // int/long/longlong) that fits. 7277 // If it's packed, check also if it fits a char or a short. 7278 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7279 BestType = Context.SignedCharTy; 7280 BestWidth = CharWidth; 7281 } else if (Packed && NumNegativeBits <= ShortWidth && 7282 NumPositiveBits < ShortWidth) { 7283 BestType = Context.ShortTy; 7284 BestWidth = ShortWidth; 7285 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7286 BestType = Context.IntTy; 7287 BestWidth = IntWidth; 7288 } else { 7289 BestWidth = Context.Target.getLongWidth(); 7290 7291 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7292 BestType = Context.LongTy; 7293 } else { 7294 BestWidth = Context.Target.getLongLongWidth(); 7295 7296 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7297 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7298 BestType = Context.LongLongTy; 7299 } 7300 } 7301 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7302 } else { 7303 // If there is no negative value, figure out the smallest type that fits 7304 // all of the enumerator values. 7305 // If it's packed, check also if it fits a char or a short. 7306 if (Packed && NumPositiveBits <= CharWidth) { 7307 BestType = Context.UnsignedCharTy; 7308 BestPromotionType = Context.IntTy; 7309 BestWidth = CharWidth; 7310 } else if (Packed && NumPositiveBits <= ShortWidth) { 7311 BestType = Context.UnsignedShortTy; 7312 BestPromotionType = Context.IntTy; 7313 BestWidth = ShortWidth; 7314 } else if (NumPositiveBits <= IntWidth) { 7315 BestType = Context.UnsignedIntTy; 7316 BestWidth = IntWidth; 7317 BestPromotionType 7318 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7319 ? Context.UnsignedIntTy : Context.IntTy; 7320 } else if (NumPositiveBits <= 7321 (BestWidth = Context.Target.getLongWidth())) { 7322 BestType = Context.UnsignedLongTy; 7323 BestPromotionType 7324 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7325 ? Context.UnsignedLongTy : Context.LongTy; 7326 } else { 7327 BestWidth = Context.Target.getLongLongWidth(); 7328 assert(NumPositiveBits <= BestWidth && 7329 "How could an initializer get larger than ULL?"); 7330 BestType = Context.UnsignedLongLongTy; 7331 BestPromotionType 7332 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7333 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7334 } 7335 } 7336 7337 // Loop over all of the enumerator constants, changing their types to match 7338 // the type of the enum if needed. 7339 for (unsigned i = 0; i != NumElements; ++i) { 7340 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7341 if (!ECD) continue; // Already issued a diagnostic. 7342 7343 // Standard C says the enumerators have int type, but we allow, as an 7344 // extension, the enumerators to be larger than int size. If each 7345 // enumerator value fits in an int, type it as an int, otherwise type it the 7346 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7347 // that X has type 'int', not 'unsigned'. 7348 7349 // Determine whether the value fits into an int. 7350 llvm::APSInt InitVal = ECD->getInitVal(); 7351 7352 // If it fits into an integer type, force it. Otherwise force it to match 7353 // the enum decl type. 7354 QualType NewTy; 7355 unsigned NewWidth; 7356 bool NewSign; 7357 if (!getLangOptions().CPlusPlus && 7358 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7359 NewTy = Context.IntTy; 7360 NewWidth = IntWidth; 7361 NewSign = true; 7362 } else if (ECD->getType() == BestType) { 7363 // Already the right type! 7364 if (getLangOptions().CPlusPlus) 7365 // C++ [dcl.enum]p4: Following the closing brace of an 7366 // enum-specifier, each enumerator has the type of its 7367 // enumeration. 7368 ECD->setType(EnumType); 7369 continue; 7370 } else { 7371 NewTy = BestType; 7372 NewWidth = BestWidth; 7373 NewSign = BestType->isSignedIntegerType(); 7374 } 7375 7376 // Adjust the APSInt value. 7377 InitVal.extOrTrunc(NewWidth); 7378 InitVal.setIsSigned(NewSign); 7379 ECD->setInitVal(InitVal); 7380 7381 // Adjust the Expr initializer and type. 7382 if (ECD->getInitExpr()) 7383 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7384 CK_IntegralCast, 7385 ECD->getInitExpr(), 7386 /*base paths*/ 0, 7387 VK_RValue)); 7388 if (getLangOptions().CPlusPlus) 7389 // C++ [dcl.enum]p4: Following the closing brace of an 7390 // enum-specifier, each enumerator has the type of its 7391 // enumeration. 7392 ECD->setType(EnumType); 7393 else 7394 ECD->setType(NewTy); 7395 } 7396 7397 Enum->completeDefinition(BestType, BestPromotionType, 7398 NumPositiveBits, NumNegativeBits); 7399} 7400 7401Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7402 StringLiteral *AsmString = cast<StringLiteral>(expr); 7403 7404 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7405 Loc, AsmString); 7406 CurContext->addDecl(New); 7407 return New; 7408} 7409 7410void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7411 SourceLocation PragmaLoc, 7412 SourceLocation NameLoc) { 7413 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7414 7415 if (PrevDecl) { 7416 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7417 } else { 7418 (void)WeakUndeclaredIdentifiers.insert( 7419 std::pair<IdentifierInfo*,WeakInfo> 7420 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7421 } 7422} 7423 7424void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7425 IdentifierInfo* AliasName, 7426 SourceLocation PragmaLoc, 7427 SourceLocation NameLoc, 7428 SourceLocation AliasNameLoc) { 7429 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7430 LookupOrdinaryName); 7431 WeakInfo W = WeakInfo(Name, NameLoc); 7432 7433 if (PrevDecl) { 7434 if (!PrevDecl->hasAttr<AliasAttr>()) 7435 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7436 DeclApplyPragmaWeak(TUScope, ND, W); 7437 } else { 7438 (void)WeakUndeclaredIdentifiers.insert( 7439 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7440 } 7441} 7442